Changes in version 0.3.5.4-alpha - 2018-11-08 Tor 0.3.5.4-alpha includes numerous bugfixes on earlier versions and improves our continuous integration support. It continues our attempts to stabilize this alpha branch and build it into a foundation for an acceptable long-term-support release. o Major bugfixes (compilation, rust): - Rust tests can now build and run successfully with the --enable-fragile-hardening option enabled. Doing this currently requires the rust beta channel; it will be possible with stable rust once Rust version 1.31 is released. Patch from Alex Crichton. Fixes bugs 27272, 27273, and 27274. Bugfix on 0.3.1.1-alpha. o Major bugfixes (embedding, main loop): - When DisableNetwork becomes set, actually disable periodic events that are already enabled. (Previously, we would refrain from enabling new ones, but we would leave the old ones turned on.) Fixes bug 28348; bugfix on 0.3.4.1-alpha. o Minor features (continuous integration): - Add a Travis CI build for --enable-nss on Linux gcc. Closes ticket 27751. - Add new CI job to Travis configuration to run stem-based integration tests. Closes ticket 27913. o Minor features (Windows, continuous integration): - Build tor on Windows Server 2012 R2 and Windows Server 2016 using Appveyor's CI. Closes ticket 28318. o Minor bugfixes (C correctness, also in 0.3.4.9): - Avoid undefined behavior in an end-of-string check when parsing the BEGIN line in a directory object. Fixes bug 28202; bugfix on 0.2.0.3-alpha. o Minor bugfixes (compilation): - Fix a pair of missing headers on OpenBSD. Fixes bug 28303; bugfix on 0.3.5.1-alpha. Patch from Kris Katterjohn. o Minor bugfixes (compilation, OpenSolaris): - Fix compilation on OpenSolaris and its descendants by adding a missing include to compat_pthreads.c. Fixes bug 27963; bugfix on 0.3.5.1-alpha. o Minor bugfixes (configuration): - Refuse to start with relative file paths and RunAsDaemon set (regression from the fix for bug 22731). Fixes bug 28298; bugfix on 0.3.3.1-alpha. o Minor bugfixes (directory authority, also in 0.3.4.9): - Log additional info when we get a relay that shares an ed25519 ID with a different relay, instead of a BUG() warning with a backtrace. Fixes bug 27800; bugfix on 0.3.2.1-alpha. o Minor bugfixes (onion service v3): - Build the service descriptor's signing key certificate before uploading, so we always have a fresh one: leaving no chances for it to expire service side. Fixes bug 27838; bugfix on 0.3.2.1-alpha. o Minor bugfixes (onion service v3, client authorization): - Fix an assert() when adding a client authorization for the first time and then sending a HUP signal to the service. Before that, Tor would stop abruptly. Fixes bug 27995; bugfix on 0.3.5.1-alpha. o Minor bugfixes (onion services): - Unless we have explicitly set HiddenServiceVersion, detect the onion service version and then look for invalid options. Previously, we did the reverse, but that broke existing configs which were pointed to a v2 service and had options like HiddenServiceAuthorizeClient set. Fixes bug 28127; bugfix on 0.3.5.1-alpha. Patch by Neel Chauhan. o Minor bugfixes (portability): - Make the OPE code (which is used for v3 onion services) run correctly on big-endian platforms. Fixes bug 28115; bugfix on 0.3.5.1-alpha. o Minor bugfixes (protover, rust): - Reject extra commas in version strings. Fixes bug 27197; bugfix on 0.3.3.3-alpha. o Minor bugfixes (relay shutdown, systemd): - Notify systemd of ShutdownWaitLength so it can be set to longer than systemd's TimeoutStopSec. In Tor's systemd service file, set TimeoutSec to 60 seconds to allow Tor some time to shut down. Fixes bug 28113; bugfix on 0.2.6.2-alpha. o Minor bugfixes (rust, also in 0.3.4.9): - Fix a potential null dereference in protover_all_supported(). Add a test for it. Fixes bug 27804; bugfix on 0.3.3.1-alpha. - Return a string that can be safely freed by C code, not one created by the rust allocator, in protover_all_supported(). Fixes bug 27740; bugfix on 0.3.3.1-alpha. o Minor bugfixes (rust, directory authority, also in 0.3.4.9): - Fix an API mismatch in the rust implementation of protover_compute_vote(). This bug could have caused crashes on any directory authorities running Tor with Rust (which we do not yet recommend). Fixes bug 27741; bugfix on 0.3.3.6. o Minor bugfixes (testing): - Avoid hangs and race conditions in test_rebind.py. Fixes bug 27968; bugfix on 0.3.5.1-alpha. o Minor bugfixes (testing, also in 0.3.4.9): - Treat backtrace test failures as expected on BSD-derived systems (NetBSD, OpenBSD, and macOS/Darwin) until we solve bug 17808. (FreeBSD failures have been treated as expected since 18204 in 0.2.8.) Fixes bug 27948; bugfix on 0.2.5.2-alpha. o Documentation (onion service manpage): - Improve HSv3 client authorization by making some options more explicit and detailed. Closes ticket 28026. Patch by Mike Tigas. Changes in version 0.3.4.9 - 2018-11-02 Tor 0.3.4.9 is the second stable release in its series; it backports numerous fixes, including a fix for a bandwidth management bug that was causing memory exhaustion on relays. Anyone running an earlier version of Tor 0.3.4.9 should upgrade. o Major bugfixes (compilation, backport from 0.3.5.3-alpha): - Fix compilation on ARM (and other less-used CPUs) when compiling with OpenSSL before 1.1. Fixes bug 27781; bugfix on 0.3.4.1-alpha. o Major bugfixes (mainloop, bootstrap, backport from 0.3.5.3-alpha): - Make sure Tor bootstraps and works properly if only the ControlPort is set. Prior to this fix, Tor would only bootstrap when a client port was set (Socks, Trans, NATD, DNS or HTTPTunnel port). Fixes bug 27849; bugfix on 0.3.4.1-alpha. o Major bugfixes (relay, backport from 0.3.5.3-alpha): - When our write bandwidth limit is exhausted, stop writing on the connection. Previously, we had a typo in the code that would make us stop reading instead, leading to relay connections being stuck indefinitely and consuming kernel RAM. Fixes bug 28089; bugfix on 0.3.4.1-alpha. o Major bugfixes (restart-in-process, backport from 0.3.5.1-alpha): - Fix a use-after-free error that could be caused by passing Tor an impossible set of options that would fail during options_act(). Fixes bug 27708; bugfix on 0.3.3.1-alpha. o Minor features (continuous integration, backport from 0.3.5.1-alpha): - Don't do a distcheck with --disable-module-dirauth in Travis. Implements ticket 27252. - Only run one online rust build in Travis, to reduce network errors. Skip offline rust builds on Travis for Linux gcc, because they're redundant. Implements ticket 27252. - Skip gcc on OSX in Travis CI, because it's rarely used. Skip a duplicate hardening-off build in Travis on Tor 0.2.9. Skip gcc on Linux with default settings, because all the non-default builds use gcc on Linux. Implements ticket 27252. o Minor features (continuous integration, backport from 0.3.5.3-alpha): - Use the Travis Homebrew addon to install packages on macOS during Travis CI. The package list is the same, but the Homebrew addon does not do a `brew update` by default. Implements ticket 27738. o Minor features (geoip): - Update geoip and geoip6 to the October 9 2018 Maxmind GeoLite2 Country database. Closes ticket 27991. o Minor bugfixes (32-bit OSX and iOS, timing, backport from 0.3.5.2-alpha): - Fix an integer overflow bug in our optimized 32-bit millisecond- difference algorithm for 32-bit Apple platforms. Previously, it would overflow when calculating the difference between two times more than 47 days apart. Fixes part of bug 27139; bugfix on 0.3.4.1-alpha. - Improve the precision of our 32-bit millisecond difference algorithm for 32-bit Apple platforms. Fixes part of bug 27139; bugfix on 0.3.4.1-alpha. - Relax the tolerance on the mainloop/update_time_jumps test when running on 32-bit Apple platforms. Fixes part of bug 27139; bugfix on 0.3.4.1-alpha. o Minor bugfixes (C correctness, to appear in 0.3.5.4-alpha): - Avoid undefined behavior in an end-of-string check when parsing the BEGIN line in a directory object. Fixes bug 28202; bugfix on 0.2.0.3-alpha. o Minor bugfixes (CI, appveyor, to appear in 0.3.5.4-alpha): - Only install the necessary mingw packages during our appveyor builds. This change makes the build a little faster, and prevents a conflict with a preinstalled mingw openssl that appveyor now ships. Fixes bugs 27943 and 27765; bugfix on 0.3.4.2-alpha. o Minor bugfixes (code safety, backport from 0.3.5.3-alpha): - Rewrite our assertion macros so that they no longer suppress the compiler's -Wparentheses warnings. Fixes bug 27709; bugfix o Minor bugfixes (continuous integration, backport from 0.3.5.1-alpha): - Stop reinstalling identical packages in our Windows CI. Fixes bug 27464; bugfix on 0.3.4.1-alpha. o Minor bugfixes (directory authority, to appear in 0.3.5.4-alpha): - Log additional info when we get a relay that shares an ed25519 ID with a different relay, instead making a BUG() warning. Fixes bug 27800; bugfix on 0.3.2.1-alpha. o Minor bugfixes (directory connection shutdown, backport from 0.3.5.1-alpha): - Avoid a double-close when shutting down a stalled directory connection. Fixes bug 26896; bugfix on 0.3.4.1-alpha. o Minor bugfixes (HTTP tunnel, backport from 0.3.5.1-alpha): - Fix a bug warning when closing an HTTP tunnel connection due to an HTTP request we couldn't handle. Fixes bug 26470; bugfix on 0.3.2.1-alpha. o Minor bugfixes (netflow padding, backport from 0.3.5.1-alpha): - Ensure circuitmux queues are empty before scheduling or sending padding. Fixes bug 25505; bugfix on 0.3.1.1-alpha. o Minor bugfixes (onion service v3, backport from 0.3.5.1-alpha): - When the onion service directory can't be created or has the wrong permissions, do not log a stack trace. Fixes bug 27335; bugfix on 0.3.2.1-alpha. o Minor bugfixes (onion service v3, backport from 0.3.5.2-alpha): - Close all SOCKS request (for the same .onion) if the newly fetched descriptor is unusable. Before that, we would close only the first one leaving the other hanging and let to time out by themselves. Fixes bug 27410; bugfix on 0.3.2.1-alpha. o Minor bugfixes (onion service v3, backport from 0.3.5.3-alpha): - When selecting a v3 rendezvous point, don't only look at the protover, but also check whether the curve25519 onion key is present. This way we avoid picking a relay that supports the v3 rendezvous but for which we don't have the microdescriptor. Fixes bug 27797; bugfix on 0.3.2.1-alpha. o Minor bugfixes (protover, backport from 0.3.5.3-alpha): - Reject protocol names containing bytes other than alphanumeric characters and hyphens ([A-Za-z0-9-]). Fixes bug 27316; bugfix on 0.2.9.4-alpha. o Minor bugfixes (rust, backport from 0.3.5.1-alpha): - Compute protover votes correctly in the rust version of the protover code. Previously, the protover rewrite in 24031 allowed repeated votes from the same voter for the same protocol version to be counted multiple times in protover_compute_vote(). Fixes bug 27649; bugfix on 0.3.3.5-rc. - Reject protover names that contain invalid characters. Fixes bug 27687; bugfix on 0.3.3.1-alpha. o Minor bugfixes (rust, backport from 0.3.5.2-alpha): - protover_all_supported() would attempt to allocate up to 16GB on some inputs, leading to a potential memory DoS. Fixes bug 27206; bugfix on 0.3.3.5-rc. o Minor bugfixes (rust, directory authority, to appear in 0.3.5.4-alpha): - Fix an API mismatch in the rust implementation of protover_compute_vote(). This bug could have caused crashes on any directory authorities running Tor with Rust (which we do not yet recommend). Fixes bug 27741; bugfix on 0.3.3.6. o Minor bugfixes (rust, to appear in 0.3.5.4-alpha): - Fix a potential null dereference in protover_all_supported(). Add a test for it. Fixes bug 27804; bugfix on 0.3.3.1-alpha. - Return a string that can be safely freed by C code, not one created by the rust allocator, in protover_all_supported(). Fixes bug 27740; bugfix on 0.3.3.1-alpha. o Minor bugfixes (testing, backport from 0.3.5.1-alpha): - If a unit test running in a subprocess exits abnormally or with a nonzero status code, treat the test as having failed, even if the test reported success. Without this fix, memory leaks don't cause the tests to fail, even with LeakSanitizer. Fixes bug 27658; bugfix on 0.2.2.4-alpha. o Minor bugfixes (testing, backport from 0.3.5.3-alpha): - Make the hs_service tests use the same time source when creating the introduction point and when testing it. Now tests work better on very slow systems like ARM or Travis. Fixes bug 27810; bugfix on 0.3.2.1-alpha. o Minor bugfixes (testing, to appear in 0.3.5.4-alpha): - Treat backtrace test failures as expected on BSD-derived systems (NetBSD, OpenBSD, and macOS/Darwin) until we solve bug 17808. (FreeBSD failures have been treated as expected since 18204 in 0.2.8.) Fixes bug 27948; bugfix on 0.2.5.2-alpha. Changes in version 0.3.5.3-alpha - 2018-10-17 Tor 0.3.5.3-alpha fixes several bugs, mostly from previous 0.3.5.x versions. One important fix for relays addresses a problem with rate- limiting code from back in 0.3.4.x: If the fix works out, we'll be backporting it soon. This release is still an alpha, but we hope it's getting closer and closer to stability. o Major features (onion services): - Version 3 onion services can now use the per-service HiddenServiceExportCircuitID option to differentiate client circuits. It communicates with the service by using the HAProxy protocol to assign virtual IP addresses to inbound client circuits. Closes ticket 4700. Patch by Mahrud Sayrafi. o Major bugfixes (compilation): - Fix compilation on ARM (and other less-used CPUs) when compiling with OpenSSL before 1.1. Fixes bug 27781; bugfix on 0.3.4.1-alpha. o Major bugfixes (initialization, crash): - Fix an assertion crash that would stop Tor from starting up if it tried to activate a periodic event too early. Fixes bug 27861; bugfix on 0.3.5.1-alpha. o Major bugfixes (mainloop, bootstrap): - Make sure Tor bootstraps and works properly if only the ControlPort is set. Prior to this fix, Tor would only bootstrap when a client port was set (Socks, Trans, NATD, DNS or HTTPTunnel port). Fixes bug 27849; bugfix on 0.3.4.1-alpha. o Major bugfixes (relay): - When our write bandwidth limit is exhausted, stop writing on the connection. Previously, we had a typo in the code that would make us stop reading instead, leading to relay connections being stuck indefinitely and consuming kernel RAM. Fixes bug 28089; bugfix on 0.3.4.1-alpha. o Minor features (continuous integration): - Use the Travis Homebrew addon to install packages on macOS during Travis CI. The package list is the same, but the Homebrew addon does not do a `brew update` by default. Implements ticket 27738. - Report what program produced the mysterious core file that we occasionally see on Travis CI during make distcheck. Closes ticket 28024. o Minor features (geoip): - Update geoip and geoip6 to the October 9 2018 Maxmind GeoLite2 Country database. Closes ticket 27991. o Minor bugfixes (code safety): - Rewrite our assertion macros so that they no longer suppress the compiler's -Wparentheses warnings. Fixes bug 27709; bugfix on 0.0.6. o Minor bugfixes (compilation): - Compile the ed25519-donna code with a correct declaration of crypto_strongest_rand(). Previously, we built it with one type, but linked it against another in the unit tests, which caused compilation failures with LTO enabled. This could have caused other undefined behavior in the tests. Fixes bug 27728; bugfix on 0.3.5.1-alpha. o Minor bugfixes (compilation, netbsd): - Add a missing include back into procmon.c. Fixes bug 27990; bugfix on 0.3.5.1-alpha. o Minor bugfixes (continuous integration, appveyor): - Install only the necessary mingw packages during our appveyor builds. This change makes the build a little faster, and prevents a conflict with a preinstalled mingw openssl that appveyor now ships. Fixes bugs 27765 and 27943; bugfix on 0.3.4.2-alpha. o Minor bugfixes (directory permissions): - When a user requests a group-readable DataDirectory, give it to them. Previously, when the DataDirectory and the CacheDirectory were the same, the default setting (0) for CacheDirectoryGroupReadable would override the setting for DataDirectoryGroupReadable. Fixes bug 26913; bugfix on 0.3.3.1-alpha. o Minor bugfixes (memory leaks): - Fix a small memory leak when calling Tor with --dump-config. Fixes bug 27893; bugfix on 0.3.2.1-alpha. o Minor bugfixes (networking): - In retry_listeners_ports(), make sure that we're removing a member of old_conns smartlist at most once. Fixes bug 27808; bugfix on 0.3.5.1-alpha. - Refrain from attempting socket rebinding when old and new listeners are in different address families. Fixes bug 27928; bugfix on 0.3.5.1-alpha. o Minor bugfixes (onion service v3): - Stop dumping a stack trace when trying to connect to an intro point without having a descriptor for it. Fixes bug 27774; bugfix on 0.3.2.1-alpha. - Don't warn so loudly when Tor is unable to decode an onion descriptor. This can now happen as a normal use case if a client gets a descriptor with client authorization but the client is not authorized. Fixes bug 27550; bugfix on 0.3.5.1-alpha. - When selecting a v3 rendezvous point, don't only look at the protover, but also check whether the curve25519 onion key is present. This way we avoid picking a relay that supports the v3 rendezvous but for which we don't have the microdescriptor. Fixes bug 27797; bugfix on 0.3.2.1-alpha. o Minor bugfixes (protover): - Reject protocol names containing bytes other than alphanumeric characters and hyphens ([A-Za-z0-9-]). Fixes bug 27316; bugfix on 0.2.9.4-alpha. o Minor bugfixes (testing): - Make the hs_service tests use the same time source when creating the introduction point and when testing it. Now tests work better on very slow systems like ARM or Travis. Fixes bug 27810; bugfix on 0.3.2.1-alpha. - In test_rebind.py, check if the Python version is in the supported range. Fixes bug 27675; bugfix on 0.3.5.1-alpha. o Code simplification and refactoring: - Divide more large Tor source files -- especially ones that span multiple areas of functionality -- into smaller parts, including onion.c and main.c. Closes ticket 26747. - Divide the "routerparse.c" module into separate modules for each group of parsed objects. Closes ticket 27924. - Move protover_rust.c to the same place protover.c was moved to. Closes ticket 27814. - Split directory.c into separate pieces for client, server, and common functionality. Closes ticket 26744. - Split the non-statistics-related parts from the rephist.c and geoip.c modules. Closes ticket 27892. - Split the router.c file into relay-only and shared components, to help with future modularization. Closes ticket 27864. o Documentation: - In the tor-resolve(1) manpage, fix the reference to socks- extensions.txt by adding a web URL. Resolves ticket 27853. - Mention that we require Python to be 2.7 or newer for some integration tests that we ship with Tor. Resolves ticket 27677. Changes in version 0.3.5.2-alpha - 2018-09-21 Tor 0.3.5.2-alpha fixes several bugs in 0.3.5.1-alpha, including one that made Tor think it had run out of sockets. Anybody running a relay or an onion service on 0.3.5.1-alpha should upgrade. o Major bugfixes (relay bandwidth statistics): - When we close relayed circuits, report the data in the circuit queues as being written in our relay bandwidth stats. This mitigates guard discovery and other attacks that close circuits for the explicit purpose of noticing this discrepancy in statistics. Fixes bug 23512; bugfix on 0.0.8pre3. o Major bugfixes (socket accounting): - In our socket accounting code, count a socket as closed even when it is closed indirectly by the TLS layer. Previously, we would count these sockets as still in use, and incorrectly believe that we had run out of sockets. Fixes bug 27795; bugfix on 0.3.5.1-alpha. o Minor bugfixes (32-bit OSX and iOS, timing): - Fix an integer overflow bug in our optimized 32-bit millisecond- difference algorithm for 32-bit Apple platforms. Previously, it would overflow when calculating the difference between two times more than 47 days apart. Fixes part of bug 27139; bugfix on 0.3.4.1-alpha. - Improve the precision of our 32-bit millisecond difference algorithm for 32-bit Apple platforms. Fixes part of bug 27139; bugfix on 0.3.4.1-alpha. - Relax the tolerance on the mainloop/update_time_jumps test when running on 32-bit Apple platforms. Fixes part of bug 27139; bugfix on 0.3.4.1-alpha. o Minor bugfixes (onion service v3): - Close all SOCKS request (for the same .onion) if the newly fetched descriptor is unusable. Before that, we would close only the first one leaving the other hanging and let to time out by themselves. Fixes bug 27410; bugfix on 0.3.2.1-alpha. o Minor bugfixes (memory leak): - Fix an unlikely memory leak when trying to read a private key from a ridiculously large file. Fixes bug 27764; bugfix on 0.3.5.1-alpha. This is CID 1439488. o Minor bugfixes (NSS): - Correctly detect failure to open a dummy TCP socket when stealing ownership of an fd from the NSS layer. Fixes bug 27782; bugfix on 0.3.5.1-alpha. o Minor bugfixes (rust): - protover_all_supported() would attempt to allocate up to 16GB on some inputs, leading to a potential memory DoS. Fixes bug 27206; bugfix on 0.3.3.5-rc. o Minor bugfixes (testing): - Revise the "conditionvar_timeout" test so that it succeeds even on heavily loaded systems where the test threads are not scheduled within 200 msec. Fixes bug 27073; bugfix on 0.2.6.3-alpha. o Code simplification and refactoring: - Divide the routerlist.c and dirserv.c modules into smaller parts. Closes ticket 27799. Changes in version 0.3.5.1-alpha - 2018-09-18 Tor 0.3.5.1-alpha is the first release of the 0.3.5.x series. It adds client authorization for modern (v3) onion services, improves bootstrap reporting, begins reorganizing Tor's codebase, adds optional support for NSS in place of OpenSSL, and much more. o Major features (onion services, UI change): - For a newly created onion service, the default version is now 3. Tor still supports existing version 2 services, but the operator now needs to set "HiddenServiceVersion 2" in order to create a new version 2 service. For existing services, Tor now learns the version by reading the key file. Closes ticket 27215. o Major features (relay, UI change): - Relays no longer run as exits by default. If the "ExitRelay" option is auto (or unset), and no exit policy is specified with ExitPolicy or ReducedExitPolicy, we now treat ExitRelay as 0. Previously in this case, we allowed exit traffic and logged a warning message. Closes ticket 21530. Patch by Neel Chauhan. - Tor now validates that the ContactInfo config option is valid UTF- 8 when parsing torrc. Closes ticket 27428. o Major features (bootstrap): - Don't report directory progress until after a connection to a relay or bridge has succeeded. Previously, we'd report 80% progress based on cached directory information when we couldn't even connect to the network. Closes ticket 27169. o Major features (new code layout): - Nearly all of Tor's source code has been moved around into more logical places. The "common" directory is now divided into a set of libraries in "lib", and files in the "or" directory have been split into "core" (logic absolutely needed for onion routing), "feature" (independent modules in Tor), and "app" (to configure and invoke the rest of Tor). See doc/HACKING/CodeStructure.md for more information. Closes ticket 26481. This refactoring is not complete: although the libraries have been refactored to be acyclic, the main body of Tor is still too interconnected. We will attempt to improve this in the future. o Major features (onion services v3): - Implement onion service client authorization at the descriptor level: only authorized clients can decrypt a service's descriptor to find out how to contact it. A new torrc option was added to control this client side: ClientOnionAuthDir . On the service side, if the "authorized_clients/" directory exists in the onion service directory path, client configurations are read from the files within. See the manpage for more details. Closes ticket 27547. Patch done by Suphanat Chunhapanya (haxxpop). - Improve revision counter generation in next-gen onion services. Onion services can now scale by hosting multiple instances on different hosts without synchronization between them, which was previously impossible because descriptors would get rejected by HSDirs. Addresses ticket 25552. o Major features (portability, cryptography, experimental, TLS): - Tor now has the option to compile with the NSS library instead of OpenSSL. This feature is experimental, and we expect that bugs may remain. It is mainly intended for environments where Tor's performance is not CPU-bound, and where NSS is already known to be installed. To try it out, configure Tor with the --enable-nss flag. Closes tickets 26631, 26815, and 26816. If you are experimenting with this option and using an old cached consensus, Tor may fail to start. To solve this, delete your "cached-consensus" and "cached-microdesc-consensus" files, (if present), and restart Tor. o Major bugfixes (directory authority): - Actually check that the address we get from DirAuthority configuration line is valid IPv4. Explicitly disallow DirAuthority address to be a DNS hostname. Fixes bug 26488; bugfix on 0.1.2.10-rc. o Major bugfixes (restart-in-process): - Fix a use-after-free error that could be caused by passing Tor an impossible set of options that would fail during options_act(). Fixes bug 27708; bugfix on 0.3.3.1-alpha. o Minor features (admin tools): - Add a new --key-expiration option to print the expiration date of the signing cert in an ed25519_signing_cert file. Resolves issue 19506. o Minor features (build): - If you pass the "--enable-pic" option to configure, Tor will try to tell the compiler to build position-independent code suitable to link into a dynamic library. (The default remains -fPIE, for code suitable for a relocatable executable.) Closes ticket 23846. o Minor features (code correctness, testing): - Tor's build process now includes a "check-includes" make target to verify that no module of Tor relies on any headers from a higher- level module. We hope to use this feature over time to help refactor our codebase. Closes ticket 26447. o Minor features (code layout): - We have a new "lowest-level" error-handling API for use by code invoked from within the logging module. With this interface, the logging code is no longer at risk of calling into itself if a failure occurs while it is trying to log something. Closes ticket 26427. o Minor features (compilation): - Tor's configure script now supports a --with-malloc= option to select your malloc implementation. Supported options are "tcmalloc", "jemalloc", "openbsd" (deprecated), and "system" (the default). Addresses part of ticket 20424. Based on a patch from Alex Xu. o Minor features (config): - The "auto" keyword in torrc is now case-insensitive. Closes ticket 26663. o Minor features (continuous integration): - Don't do a distcheck with --disable-module-dirauth in Travis. Implements ticket 27252. - Install libcap-dev and libseccomp2-dev so these optional dependencies get tested on Travis CI. Closes ticket 26560. - Only run one online rust build in Travis, to reduce network errors. Skip offline rust builds on Travis for Linux gcc, because they're redundant. Implements ticket 27252. - Skip gcc on OSX in Travis CI, because it's rarely used. Skip a duplicate hardening-off build in Travis on Tor 0.2.9. Skip gcc on Linux with default settings, because all the non-default builds use gcc on Linux. Implements ticket 27252. o Minor features (controller): - Emit CIRC_BW events as soon as we detect that we processed an invalid or otherwise dropped cell on a circuit. This allows vanguards and other controllers to react more quickly to dropped cells. Closes ticket 27678. - For purposes of CIRC_BW-based dropped cell detection, track half- closed stream ids, and allow their ENDs, SENDMEs, DATA and path bias check cells to arrive without counting it as dropped until either the END arrives, or the windows are empty. Closes ticket 25573. - Implement a 'GETINFO md/all' controller command to enable getting all known microdescriptors. Closes ticket 8323. - The GETINFO command now support an "uptime" argument, to return Tor's uptime in seconds. Closes ticket 25132. o Minor features (denial-of-service avoidance): - Make our OOM handler aware of the DNS cache so that it doesn't fill up the memory. This check is important for our DoS mitigation subsystem. Closes ticket 18642. Patch by Neel Chauhan. o Minor features (development): - Tor's makefile now supports running the "clippy" Rust style tool on our Rust code. Closes ticket 22156. o Minor features (directory authority): - There is no longer an artificial upper limit on the length of bandwidth lines. Closes ticket 26223. - When a bandwidth file is used to obtain the bandwidth measurements, include this bandwidth file headers in the votes. Closes ticket 3723. - Improved support for networks with only a single authority or a single fallback directory. Patch from Gabriel Somlo. Closes ticket 25928. o Minor features (embedding API): - The Tor controller API now supports a function to launch Tor with a preconstructed owning controller FD, so that embedding applications don't need to manage controller ports and authentication. Closes ticket 24204. - The Tor controller API now has a function that returns the name and version of the backend implementing the API. Closes ticket 26947. o Minor features (geoip): - Update geoip and geoip6 to the September 6 2018 Maxmind GeoLite2 Country database. Closes ticket 27631. o Minor features (memory management): - Get Libevent to use the same memory allocator as Tor, by calling event_set_mem_functions() during initialization. Resolves ticket 8415. o Minor features (memory usage): - When not using them, store legacy TAP public onion keys in DER- encoded format, rather than as expanded public keys. This should save several megabytes on typical clients. Closes ticket 27246. o Minor features (OpenSSL): - When possible, use RFC5869 HKDF implementation from OpenSSL rather than our own. Resolves ticket 19979. o Minor features (Rust, code quality): - Improve rust code quality in the rust protover implementation by making it more idiomatic. Includes changing an internal API to take &str instead of &String. Closes ticket 26492. o Minor features (testing): - Add scripts/test/chutney-git-bisect.sh, for bisecting using chutney. Implements ticket 27211. o Minor features (tor-resolve): - The tor-resolve utility can now be used with IPv6 SOCKS proxies. Side-effect of the refactoring for ticket 26526. o Minor features (UI): - Log each included configuration file or directory as we read it, to provide more visibility about where Tor is reading from. Patch from Unto Sten; closes ticket 27186. - Lower log level of "Scheduler type KIST has been enabled" to INFO. Closes ticket 26703. o Minor bugfixes (bootstrap): - Try harder to get descriptors in non-exit test networks, by using the mid weight for the third hop when there are no exits. Fixes bug 27237; bugfix on 0.2.6.2-alpha. o Minor bugfixes (C correctness): - Avoid casting smartlist index to int implicitly, as it may trigger a warning (-Wshorten-64-to-32). Fixes bug 26282; bugfix on 0.2.3.13-alpha, 0.2.7.1-alpha and 0.2.1.1-alpha. - Use time_t for all values in predicted_ports_prediction_time_remaining(). Rework the code that computes difference between durations/timestamps. Fixes bug 27165; bugfix on 0.3.1.1-alpha. o Minor bugfixes (client, memory usage): - When not running as a directory cache, there is no need to store the text of the current consensus networkstatus in RAM. Previously, however, clients would store it anyway, at a cost of over 5 MB. Now, they do not. Fixes bug 27247; bugfix on 0.3.0.1-alpha. o Minor bugfixes (client, reachableaddresses): - Instead of adding a "reject *:*" line to ReachableAddresses when loading the configuration, add one to the policy after parsing it in parse_reachable_addresses(). This prevents extra "reject *.*" lines from accumulating on reloads. Fixes bug 20874; bugfix on 0.1.1.5-alpha. Patch by Neel Chauhan. o Minor bugfixes (code quality): - Rename sandbox_getaddrinfo() and other functions to no longer misleadingly suggest that they are sandbox-only. Fixes bug 26525; bugfix on 0.2.7.1-alpha. o Minor bugfixes (configuration, Onion Services): - In rend_service_parse_port_config(), disallow any input to remain after address-port pair was parsed. This will catch address and port being whitespace-separated by mistake of the user. Fixes bug 27044; bugfix on 0.2.9.10. o Minor bugfixes (continuous integration): - Stop reinstalling identical packages in our Windows CI. Fixes bug 27464; bugfix on 0.3.4.1-alpha. o Minor bugfixes (controller): - Consider all routerinfo errors other than "not a server" to be transient for the purpose of "GETINFO exit-policy/*" controller request. Print stacktrace in the unlikely case of failing to recompute routerinfo digest. Fixes bug 27034; bugfix on 0.3.4.1-alpha. o Minor bugfixes (directory connection shutdown): - Avoid a double-close when shutting down a stalled directory connection. Fixes bug 26896; bugfix on 0.3.4.1-alpha. o Minor bugfixes (HTTP tunnel): - Fix a bug warning when closing an HTTP tunnel connection due to an HTTP request we couldn't handle. Fixes bug 26470; bugfix on 0.3.2.1-alpha. o Minor bugfixes (ipv6): - In addrs_in_same_network_family(), we choose the subnet size based on the IP version (IPv4 or IPv6). Previously, we chose a fixed subnet size of /16 for both IPv4 and IPv6 addresses. Fixes bug 15518; bugfix on 0.2.3.1-alpha. Patch by Neel Chauhan. o Minor bugfixes (logging): - As a precaution, do an early return from log_addr_has_changed() if Tor is running as client. Also, log a stack trace for debugging as this function should only be called when Tor runs as server. Fixes bug 26892; bugfix on 0.1.1.9-alpha. - Refrain from mentioning bug 21018 in the logs, as it is already fixed. Fixes bug 25477; bugfix on 0.2.9.8. o Minor bugfixes (logging, documentation): - When SafeLogging is enabled, scrub IP address in channel_tls_process_netinfo_cell(). Also, add a note to manpage that scrubbing is not guaranteed on loglevels below Notice. Fixes bug 26882; bugfix on 0.2.4.10-alpha. o Minor bugfixes (netflow padding): - Ensure circuitmux queues are empty before scheduling or sending padding. Fixes bug 25505; bugfix on 0.3.1.1-alpha. o Minor bugfixes (onion service v2): - Log at level "info", not "warning", in the case that we do not have a consensus when a .onion request comes in. This can happen normally while bootstrapping. Fixes bug 27040; bugfix on 0.2.8.2-alpha. o Minor bugfixes (onion service v3): - When the onion service directory can't be created or has the wrong permissions, do not log a stack trace. Fixes bug 27335; bugfix on 0.3.2.1-alpha. o Minor bugfixes (OS compatibility): - Properly handle configuration changes that move a listener to/from wildcard IP address. If the first attempt to bind a socket fails, close the old listener and try binding the socket again. Fixes bug 17873; bugfix on 0.0.8pre-1. o Minor bugfixes (performance):: - Rework node_is_a_configured_bridge() to no longer call node_get_all_orports(), which was performing too many memory allocations. Fixes bug 27224; bugfix on 0.2.3.9. o Minor bugfixes (relay statistics): - Update relay descriptor on bandwidth changes only when the uptime is smaller than 24h, in order to reduce the efficiency of guard discovery attacks. Fixes bug 24104; bugfix on 0.1.1.6-alpha. o Minor bugfixes (relays): - Consider the fact that we'll be making direct connections to our entry and guard nodes when computing the fraction of nodes that have their descriptors. Also, if we are using bridges and there is at least one bridge with a full descriptor, treat the fraction of guards available as 100%. Fixes bug 25886; bugfix on 0.2.4.10-alpha. Patch by Neel Chauhan. - Update the message logged on relays when DirCache is disabled. Since 0.3.3.5-rc, authorities require DirCache (V2Dir) for the Guard flag. Fixes bug 24312; bugfix on 0.3.3.5-rc. o Minor bugfixes (rust, protover): - Compute protover votes correctly in the rust version of the protover code. Previously, the protover rewrite in 24031 allowed repeated votes from the same voter for the same protocol version to be counted multiple times in protover_compute_vote(). Fixes bug 27649; bugfix on 0.3.3.5-rc. - Reject protover names that contain invalid characters. Fixes bug 27687; bugfix on 0.3.3.1-alpha. o Minor bugfixes (testing): - Fix two unit tests to work when HOME environment variable is not set. Fixes bug 27096; bugfix on 0.2.8.1-alpha. - If a unit test running in a subprocess exits abnormally or with a nonzero status code, treat the test as having failed, even if the test reported success. Without this fix, memory leaks don't cause the tests to fail, even with LeakSanitizer. Fixes bug 27658; bugfix on 0.2.2.4-alpha. - When logging a version mismatch in our openssl_version tests, report the actual offending version strings. Fixes bug 26152; bugfix on 0.2.9.1-alpha. - Fix forking tests on Windows when there is a space somewhere in the path. Fixes bug 26437; bugfix on 0.2.2.4-alpha. o Code simplification and refactoring: - 'updateFallbackDirs.py' now ignores the blacklist file, as it's not longer needed. Closes ticket 26502. - Include paths to header files within Tor are now qualified by directory within the top-level src directory. - Many structures have been removed from the centralized "or.h" header, and moved into their own headers. This will allow us to reduce the number of places in the code that rely on each structure's contents and layout. Closes ticket 26383. - Remove ATTR_NONNULL macro from codebase. Resolves ticket 26527. - Remove GetAdaptersAddresses_fn_t. The code that used it was removed as part of the 26481 refactor. Closes ticket 27467. - Rework Tor SOCKS server code to use Trunnel and benefit from autogenerated functions for parsing and generating SOCKS wire format. New implementation is cleaner, more maintainable and should be less prone to heartbleed-style vulnerabilities. Implements a significant fraction of ticket 3569. - Split sampled_guards_update_from_consensus() and select_entry_guard_for_circuit() into subfunctions. In entry_guards_update_primary() unite three smartlist enumerations into one and move smartlist comparison code out of the function. Closes ticket 21349. - Tor now assumes that you have standards-conformant stdint.h and inttypes.h headers when compiling. Closes ticket 26626. - Unify our bloom filter logic. Previously we had two copies of this code: one for routerlist filtering, and one for address set calculations. Closes ticket 26510. - Use the simpler strcmpstart() helper in rend_parse_v2_service_descriptor instead of strncmp(). Closes ticket 27630. - Utility functions that can perform a DNS lookup are now wholly separated from those that can't, in separate headers and C modules. Closes ticket 26526. o Documentation: - Copy paragraph and URL to Tor's code of conduct document from CONTRIBUTING to new CODE_OF_CONDUCT file. Resolves ticket 26638. - Remove old instructions from INSTALL document. Closes ticket 26588. - Warn users that they should not include MyFamily line(s) in their torrc when running Tor bridge. Closes ticket 26908. o Removed features: - Tor no longer supports building with the dmalloc library. For debugging memory issues, we suggest using gperftools or msan instead. Closes ticket 26426. - Tor no longer attempts to run on Windows environments without the GetAdaptersAddresses() function. This function has existed since Windows XP, which is itself already older than we support. - Remove Tor2web functionality for version 2 onion services. The Tor2webMode and Tor2webRendezvousPoints options are now obsolete. (This feature was never shipped in vanilla Tor and it was only possible to use this feature by building the support at compile time. Tor2webMode is not implemented for version 3 onion services.) Closes ticket 26367. Changes in version 0.2.9.17 - 2018-09-10 Tor 0.2.9.17 backports numerous bugfixes from later versions of Tor. o Minor features (compatibility, backport from 0.3.4.8): - Tell OpenSSL to maintain backward compatibility with previous RSA1024/DH1024 users in Tor. With OpenSSL 1.1.1-pre6, these ciphers are disabled by default. Closes ticket 27344. o Minor features (continuous integration, backport from 0.3.4.7-rc): - Enable macOS builds in our Travis CI configuration. Closes ticket 24629. - Install libcap-dev and libseccomp2-dev so these optional dependencies get tested on Travis CI. Closes ticket 26560. - Run asciidoc during Travis CI. Implements ticket 27087. - Use ccache in our Travis CI configuration. Closes ticket 26952. o Minor features (geoip): - Update geoip and geoip6 to the August 7 2018 Maxmind GeoLite2 Country database. Closes ticket 27089. o Minor bugfixes (compilation, backport from 0.3.4.6-rc): - When compiling with --enable-openbsd-malloc or --enable-tcmalloc, tell the compiler not to include the system malloc implementation. Fixes bug 20424; bugfix on 0.2.0.20-rc. o Minor bugfixes (compilation, backport from 0.3.4.7-rc): - Silence a spurious compiler warning on the GetAdaptersAddresses function pointer cast. This issue is already fixed by 26481 in 0.3.5 and later, by removing the lookup and cast. Fixes bug 27465; bugfix on 0.2.3.11-alpha. - Stop calling SetProcessDEPPolicy() on 64-bit Windows. It is not supported, and always fails. Some compilers warn about the function pointer cast on 64-bit Windows. Fixes bug 27461; bugfix on 0.2.2.23-alpha. o Minor bugfixes (compilation, windows, backport from 0.3.4.7-rc): - Don't link or search for pthreads when building for Windows, even if we are using build environment (like mingw) that provides a pthreads library. Fixes bug 27081; bugfix on 0.1.0.1-rc. o Minor bugfixes (continuous integration, backport from 0.3.4.6-rc): - Skip a pair of unreliable key generation tests on Windows, until the underlying issue in bug 26076 is resolved. Fixes bug 26830 and bug 26853; bugfix on 0.2.7.3-rc and 0.3.2.1-alpha respectively. o Minor bugfixes (continuous integration, backport from 0.3.4.7-rc): - Pass the module flags to distcheck configure, and log the flags before running configure. (Backported to 0.2.9 and later as a precaution.) Fixes bug 27088; bugfix on 0.3.4.1-alpha. o Minor bugfixes (continuous integration, backport from 0.3.4.8): - When a Travis build fails, and showing a log fails, keep trying to show the other logs. Fixes bug 27453; bugfix on 0.3.4.7-rc. - When we use echo in Travis, don't pass a --flag as the first argument. Fixes bug 27418; bugfix on 0.3.4.7-rc. o Minor bugfixes (directory authority, backport from 0.3.4.6-rc): - When voting for recommended versions, make sure that all of the versions are well-formed and parsable. Fixes bug 26485; bugfix on 0.1.1.6-alpha. o Minor bugfixes (linux seccomp2 sandbox, backport from 0.3.4.7-rc): - Fix a bug in out sandboxing rules for the openat() syscall. Previously, no openat() call would be permitted, which would break filesystem operations on recent glibc versions. Fixes bug 25440; bugfix on 0.2.9.15. Diagnosis and patch from Daniel Pinto. o Minor bugfixes (onion services, backport from 0.3.4.8): - Silence a spurious compiler warning in rend_client_send_introduction(). Fixes bug 27463; bugfix on 0.1.1.2-alpha. o Minor bugfixes (single onion services, Tor2web, backport from 0.3.4.6-rc): - Log a protocol warning when single onion services or Tor2web clients fail to authenticate direct connections to relays. Fixes bug 26924; bugfix on 0.2.9.1-alpha. o Minor bugfixes (testing, backport from 0.3.4.6-rc): - Disable core dumps in test_bt.sh, to avoid failures in "make distcheck". Fixes bug 26787; bugfix on 0.2.5.2-alpha. o Minor bugfixes (testing, chutney, backport from 0.3.4.8): - Before running make test-network-all, delete old logs and test result files, to avoid spurious failures. Fixes bug 27295; bugfix on 0.2.7.3-rc. o Minor bugfixes (testing, openssl compatibility, backport from 0.3.4.7-rc): - Our "tortls/cert_matches_key" unit test no longer relies on OpenSSL internals. Previously, it relied on unsupported OpenSSL behavior in a way that caused it to crash with OpenSSL 1.0.2p. Fixes bug 27226; bugfix on 0.2.5.1-alpha. o Minor bugfixes (Windows, compilation, backport from 0.3.4.7-rc): - Silence a compilation warning on MSVC 2017 and clang-cl. Fixes bug 27185; bugfix on 0.2.2.2-alpha. Changes in version 0.3.2.12 - 2018-09-10 Tor 0.3.2.12 backport numerous fixes from later versions of Tor. o Minor features (compatibility, backport from 0.3.4.8): - Tell OpenSSL to maintain backward compatibility with previous RSA1024/DH1024 users in Tor. With OpenSSL 1.1.1-pre6, these ciphers are disabled by default. Closes ticket 27344. o Minor features (continuous integration, backport from 0.3.4.7-rc): - Enable macOS builds in our Travis CI configuration. Closes ticket 24629. - Install libcap-dev and libseccomp2-dev so these optional dependencies get tested on Travis CI. Closes ticket 26560. - Run asciidoc during Travis CI. Implements ticket 27087. - Use ccache in our Travis CI configuration. Closes ticket 26952. o Minor features (continuous integration, rust, backport from 0.3.4.7-rc): - Use cargo cache in our Travis CI configuration. Closes ticket 26952. o Minor features (controller, backport from 0.3.4.6-rc): - The control port now exposes the list of HTTPTunnelPorts and ExtOrPorts via GETINFO net/listeners/httptunnel and net/listeners/extor respectively. Closes ticket 26647. o Minor features (directory authorities, backport from 0.3.4.7-rc): - Authorities no longer vote to make the subprotocol version "LinkAuth=1" a requirement: it is unsupportable with NSS, and hasn't been needed since Tor 0.3.0.1-alpha. Closes ticket 27286. o Minor features (geoip): - Update geoip and geoip6 to the August 7 2018 Maxmind GeoLite2 Country database. Closes ticket 27089. o Minor bugfixes (compilation, backport from 0.3.4.6-rc): - When compiling with --enable-openbsd-malloc or --enable-tcmalloc, tell the compiler not to include the system malloc implementation. Fixes bug 20424; bugfix on 0.2.0.20-rc. - Don't try to use a pragma to temporarily disable the -Wunused-const-variable warning if the compiler doesn't support it. Fixes bug 26785; bugfix on 0.3.2.11. o Minor bugfixes (compilation, backport from 0.3.4.7-rc): - Silence a spurious compiler warning on the GetAdaptersAddresses function pointer cast. This issue is already fixed by 26481 in 0.3.5 and later, by removing the lookup and cast. Fixes bug 27465; bugfix on 0.2.3.11-alpha. - Stop calling SetProcessDEPPolicy() on 64-bit Windows. It is not supported, and always fails. Some compilers warn about the function pointer cast on 64-bit Windows. Fixes bug 27461; bugfix on 0.2.2.23-alpha. o Minor bugfixes (compilation, windows, backport from 0.3.4.7-rc): - Don't link or search for pthreads when building for Windows, even if we are using build environment (like mingw) that provides a pthreads library. Fixes bug 27081; bugfix on 0.1.0.1-rc. o Minor bugfixes (continuous integration, backport from 0.3.4.6-rc): - Skip a pair of unreliable key generation tests on Windows, until the underlying issue in bug 26076 is resolved. Fixes bug 26830 and bug 26853; bugfix on 0.2.7.3-rc and 0.3.2.1-alpha respectively. o Minor bugfixes (continuous integration, backport from 0.3.4.7-rc): - Build with zstd on macOS. Fixes bug 27090; bugfix on 0.3.1.5-alpha. - Pass the module flags to distcheck configure, and log the flags before running configure. (Backported to 0.2.9 and later as a precaution.) Fixes bug 27088; bugfix on 0.3.4.1-alpha. o Minor bugfixes (continuous integration, backport from 0.3.4.8): - When a Travis build fails, and showing a log fails, keep trying to show the other logs. Fixes bug 27453; bugfix on 0.3.4.7-rc. - When we use echo in Travis, don't pass a --flag as the first argument. Fixes bug 27418; bugfix on 0.3.4.7-rc. o Minor bugfixes (directory authority, backport from 0.3.4.6-rc): - When voting for recommended versions, make sure that all of the versions are well-formed and parsable. Fixes bug 26485; bugfix on 0.1.1.6-alpha. o Minor bugfixes (linux seccomp2 sandbox, backport from 0.3.4.7-rc): - Fix a bug in out sandboxing rules for the openat() syscall. Previously, no openat() call would be permitted, which would break filesystem operations on recent glibc versions. Fixes bug 25440; bugfix on 0.2.9.15. Diagnosis and patch from Daniel Pinto. o Minor bugfixes (logging, backport from 0.3.4.6-rc): - Improve the log message when connection initiators fail to authenticate direct connections to relays. Fixes bug 26927; bugfix on 0.3.0.1-alpha. o Minor bugfixes (onion services, backport from 0.3.4.7-rc): - Fix bug that causes services to not ever rotate their descriptors if they were getting SIGHUPed often. Fixes bug 26932; bugfix on 0.3.2.1-alpha. o Minor bugfixes (onion services, backport from 0.3.4.8): - Silence a spurious compiler warning in rend_client_send_introduction(). Fixes bug 27463; bugfix on 0.1.1.2-alpha. o Minor bugfixes (rust, backport from 0.3.4.7-rc): - Backport test_rust.sh from master. Fixes bug 26497; bugfix on 0.3.1.5-alpha. - Consistently use ../../.. as a fallback for $abs_top_srcdir in test_rust.sh. Fixes bug 27093; bugfix on 0.3.4.3-alpha. - Stop setting $CARGO_HOME. cargo will use the user's $CARGO_HOME, or $HOME/.cargo by default. Fixes bug 26497; bugfix on 0.3.1.5-alpha. o Minor bugfixes (single onion services, Tor2web, backport from 0.3.4.6-rc): - Log a protocol warning when single onion services or Tor2web clients fail to authenticate direct connections to relays. Fixes bug 26924; bugfix on 0.2.9.1-alpha. o Minor bugfixes (testing, backport from 0.3.4.6-rc): - Disable core dumps in test_bt.sh, to avoid failures in "make distcheck". Fixes bug 26787; bugfix on 0.2.5.2-alpha. o Minor bugfixes (testing, chutney, backport from 0.3.4.8): - When running make test-network-all, use the mixed+hs-v2 network. (A previous fix to chutney removed v3 onion services from the mixed+hs-v23 network, so seeing "mixed+hs-v23" in tests is confusing.) Fixes bug 27345; bugfix on 0.3.2.1-alpha. - Before running make test-network-all, delete old logs and test result files, to avoid spurious failures. Fixes bug 27295; bugfix on 0.2.7.3-rc. o Minor bugfixes (testing, openssl compatibility): - Our "tortls/cert_matches_key" unit test no longer relies on OpenSSL internals. Previously, it relied on unsupported OpenSSL behavior in a way that caused it to crash with OpenSSL 1.0.2p. Fixes bug 27226; bugfix on 0.2.5.1-alpha. o Minor bugfixes (testing, openssl compatibility, backport from 0.3.4.7-rc): - Our "tortls/cert_matches_key" unit test no longer relies on OpenSSL internals. Previously, it relied on unsupported OpenSSL behavior in a way that caused it to crash with OpenSSL 1.0.2p. Fixes bug 27226; bugfix on 0.2.5.1-alpha. o Minor bugfixes (Windows, compilation, backport from 0.3.4.7-rc): - Silence a compilation warning on MSVC 2017 and clang-cl. Fixes bug 27185; bugfix on 0.2.2.2-alpha. Changes in version 0.3.3.10 - 2018-09-10 Tor 0.3.3.10 backports numerous fixes from later versions of Tor. o Minor features (bug workaround, backport from 0.3.4.7-rc): - Compile correctly on systems that provide the C11 stdatomic.h header, but where C11 atomic functions don't actually compile. Closes ticket 26779; workaround for Debian issue 903709. o Minor features (compatibility, backport from 0.3.4.8): - Tell OpenSSL to maintain backward compatibility with previous RSA1024/DH1024 users in Tor. With OpenSSL 1.1.1-pre6, these ciphers are disabled by default. Closes ticket 27344. o Minor features (continuous integration, backport from 0.3.4.7-rc): - Backport Travis rust distcheck to 0.3.3. Closes ticket 24629. - Enable macOS builds in our Travis CI configuration. Closes ticket 24629. - Install libcap-dev and libseccomp2-dev so these optional dependencies get tested on Travis CI. Closes ticket 26560. - Run asciidoc during Travis CI. Implements ticket 27087. - Use ccache in our Travis CI configuration. Closes ticket 26952. o Minor features (continuous integration, rust, backport from 0.3.4.7-rc): - Use cargo cache in our Travis CI configuration. Closes ticket 26952. o Minor features (controller, backport from 0.3.4.6-rc): - The control port now exposes the list of HTTPTunnelPorts and ExtOrPorts via GETINFO net/listeners/httptunnel and net/listeners/extor respectively. Closes ticket 26647. o Minor features (directory authorities, backport from 0.3.4.7-rc): - Authorities no longer vote to make the subprotocol version "LinkAuth=1" a requirement: it is unsupportable with NSS, and hasn't been needed since Tor 0.3.0.1-alpha. Closes ticket 27286. o Minor features (geoip): - Update geoip and geoip6 to the August 7 2018 Maxmind GeoLite2 Country database. Closes ticket 27089. o Minor bugfixes (compilation, backport from 0.3.4.6-rc): - When compiling with --enable-openbsd-malloc or --enable-tcmalloc, tell the compiler not to include the system malloc implementation. Fixes bug 20424; bugfix on 0.2.0.20-rc. - Don't try to use a pragma to temporarily disable the -Wunused-const-variable warning if the compiler doesn't support it. Fixes bug 26785; bugfix on 0.3.2.11. o Minor bugfixes (compilation, backport from 0.3.4.7-rc): - Silence a spurious compiler warning on the GetAdaptersAddresses function pointer cast. This issue is already fixed by 26481 in 0.3.5 and later, by removing the lookup and cast. Fixes bug 27465; bugfix on 0.2.3.11-alpha. - Stop calling SetProcessDEPPolicy() on 64-bit Windows. It is not supported, and always fails. Some compilers warn about the function pointer cast on 64-bit Windows. Fixes bug 27461; bugfix on 0.2.2.23-alpha. o Minor bugfixes (compilation, windows, backport from 0.3.4.7-rc): - Don't link or search for pthreads when building for Windows, even if we are using build environment (like mingw) that provides a pthreads library. Fixes bug 27081; bugfix on 0.1.0.1-rc. o Minor bugfixes (continuous integration, backport from 0.3.4.6-rc): - Skip a pair of unreliable key generation tests on Windows, until the underlying issue in bug 26076 is resolved. Fixes bug 26830 and bug 26853; bugfix on 0.2.7.3-rc and 0.3.2.1-alpha respectively. o Minor bugfixes (continuous integration, backport from 0.3.4.7-rc): - Build with zstd on macOS. Fixes bug 27090; bugfix on 0.3.1.5-alpha. - Pass the module flags to distcheck configure, and log the flags before running configure. (Backported to 0.2.9 and later as a precaution.) Fixes bug 27088; bugfix on 0.3.4.1-alpha. o Minor bugfixes (continuous integration, backport from 0.3.4.8): - When a Travis build fails, and showing a log fails, keep trying to show the other logs. Fixes bug 27453; bugfix on 0.3.4.7-rc. - When we use echo in Travis, don't pass a --flag as the first argument. Fixes bug 27418; bugfix on 0.3.4.7-rc. o Minor bugfixes (directory authority, backport from 0.3.4.6-rc): - When voting for recommended versions, make sure that all of the versions are well-formed and parsable. Fixes bug 26485; bugfix on 0.1.1.6-alpha. o Minor bugfixes (in-process restart, backport from 0.3.4.7-rc): - Always call tor_free_all() when leaving tor_run_main(). When we did not, restarting tor in-process would cause an assertion failure. Fixes bug 26948; bugfix on 0.3.3.1-alpha. o Minor bugfixes (linux seccomp2 sandbox, backport from 0.3.4.7-rc): - Fix a bug in our sandboxing rules for the openat() syscall. Previously, no openat() call would be permitted, which would break filesystem operations on recent glibc versions. Fixes bug 25440; bugfix on 0.2.9.15. Diagnosis and patch from Daniel Pinto. o Minor bugfixes (logging, backport from 0.3.4.6-rc): - Improve the log message when connection initiators fail to authenticate direct connections to relays. Fixes bug 26927; bugfix on 0.3.0.1-alpha. o Minor bugfixes (onion services, backport from 0.3.4.7-rc): - Fix bug that causes services to not ever rotate their descriptors if they were getting SIGHUPed often. Fixes bug 26932; bugfix on 0.3.2.1-alpha. o Minor bugfixes (onion services, backport from 0.3.4.8): - Silence a spurious compiler warning in rend_client_send_introduction(). Fixes bug 27463; bugfix on 0.1.1.2-alpha. o Minor bugfixes (portability, backport from 0.3.4.6-rc): - Work around two different bugs in the OS X 10.10 and later SDKs that would prevent us from successfully targeting earlier versions of OS X. Fixes bug 26876; bugfix on 0.3.3.1-alpha. o Minor bugfixes (portability, backport from 0.3.4.7-rc): - Fix compilation of the unit tests on GNU/Hurd, which does not define PATH_MAX. Fixes bug 26873; bugfix on 0.3.3.1-alpha. Patch from "paulusASol". o Minor bugfixes (rust, backport from 0.3.4.7-rc): - Backport test_rust.sh from master. Fixes bug 26497; bugfix on 0.3.1.5-alpha. - Consistently use ../../.. as a fallback for $abs_top_srcdir in test_rust.sh. Fixes bug 27093; bugfix on 0.3.4.3-alpha. - Protover parsing was accepting the presence of whitespace in version strings, which the C implementation would choke on, e.g. "Desc=1\t,2". Fixes bug 27177; bugfix on 0.3.3.5-rc. - Protover parsing was ignoring a 2nd hyphen and everything after it, accepting entries like "Link=1-5-foo". Fixes bug 27164; bugfix on 0.3.3.1-alpha. - Stop setting $CARGO_HOME. cargo will use the user's $CARGO_HOME, or $HOME/.cargo by default. Fixes bug 26497; bugfix on 0.3.1.5-alpha. - cd to ${abs_top_builddir}/src/rust before running cargo in src/test/test_rust.sh. This makes the working directory consistent between builds and tests. Fixes bug 26497; bugfix on 0.3.3.2-alpha. o Minor bugfixes (single onion services, Tor2web, backport from 0.3.4.6-rc): - Log a protocol warning when single onion services or Tor2web clients fail to authenticate direct connections to relays. Fixes bug 26924; bugfix on 0.2.9.1-alpha. o Minor bugfixes (testing, backport from 0.3.4.6-rc): - Disable core dumps in test_bt.sh, to avoid failures in "make distcheck". Fixes bug 26787; bugfix on 0.2.5.2-alpha. o Minor bugfixes (testing, chutney, backport from 0.3.4.8): - When running make test-network-all, use the mixed+hs-v2 network. (A previous fix to chutney removed v3 onion services from the mixed+hs-v23 network, so seeing "mixed+hs-v23" in tests is confusing.) Fixes bug 27345; bugfix on 0.3.2.1-alpha. - Before running make test-network-all, delete old logs and test result files, to avoid spurious failures. Fixes bug 27295; bugfix on 0.2.7.3-rc. o Minor bugfixes (testing, openssl compatibility, backport from 0.3.4.7-rc): - Our "tortls/cert_matches_key" unit test no longer relies on OpenSSL internals. Previously, it relied on unsupported OpenSSL behavior in a way that caused it to crash with OpenSSL 1.0.2p. Fixes bug 27226; bugfix on 0.2.5.1-alpha. o Minor bugfixes (v3 onion services, backport from 0.3.4.6-rc): - Stop sending ed25519 link specifiers in v3 onion service introduce cells and descriptors, when the rendezvous or introduction point doesn't support ed25519 link authentication. Fixes bug 26627; bugfix on 0.3.2.4-alpha. o Minor bugfixes (Windows, compilation, backport from 0.3.4.7-rc): - Silence a compilation warning on MSVC 2017 and clang-cl. Fixes bug 27185; bugfix on 0.2.2.2-alpha. Changes in version 0.3.4.8 - 2018-09-10 Tor 0.3.4.8 is the first stable release in its series; it includes compilation and portability fixes. The Tor 0.3.4 series includes improvements for running Tor in low-power and embedded environments, which should help performance in general. We've begun work on better modularity, and included preliminary changes on the directory authority side to accommodate a new bandwidth measurement system. We've also integrated more continuous-integration systems into our development process, and made corresponding changes to Tor's testing infrastructure. Finally, we've continued to refine our anti-denial-of-service code. Below are the changes since 0.3.4.7-rc. For a complete list of changes since 0.3.3.9, see the ReleaseNotes file. o Minor features (compatibility): - Tell OpenSSL to maintain backward compatibility with previous RSA1024/DH1024 users in Tor. With OpenSSL 1.1.1-pre6, these ciphers are disabled by default. Closes ticket 27344. o Minor features (continuous integration): - Log the compiler path and version during Appveyor builds. Implements ticket 27449. - Show config.log and test-suite.log after failed Appveyor builds. Also upload the zipped full logs as a build artifact. Implements ticket 27430. o Minor bugfixes (compilation): - Silence a spurious compiler warning on the GetAdaptersAddresses function pointer cast. This issue is already fixed by 26481 in 0.3.5 and later, by removing the lookup and cast. Fixes bug 27465; bugfix on 0.2.3.11-alpha. - Stop calling SetProcessDEPPolicy() on 64-bit Windows. It is not supported, and always fails. Some compilers warn about the function pointer cast on 64-bit Windows. Fixes bug 27461; bugfix on 0.2.2.23-alpha. o Minor bugfixes (continuous integration): - Disable gcc hardening in Appveyor Windows 64-bit builds. As of August 29 2018, Appveyor images come with gcc 8.2.0 by default. Executables compiled for 64-bit Windows with this version of gcc crash when Tor's --enable-gcc-hardening flag is set. Fixes bug 27460; bugfix on 0.3.4.1-alpha. - When a Travis build fails, and showing a log fails, keep trying to show the other logs. Fixes bug 27453; bugfix on 0.3.4.7-rc. - When we use echo in Travis, don't pass a --flag as the first argument. Fixes bug 27418; bugfix on 0.3.4.7-rc. o Minor bugfixes (onion services): - Silence a spurious compiler warning in rend_client_send_introduction(). Fixes bug 27463; bugfix on 0.1.1.2-alpha. o Minor bugfixes (testing, chutney): - When running make test-network-all, use the mixed+hs-v2 network. (A previous fix to chutney removed v3 onion services from the mixed+hs-v23 network, so seeing "mixed+hs-v23" in tests is confusing.) Fixes bug 27345; bugfix on 0.3.2.1-alpha. - Before running make test-network-all, delete old logs and test result files, to avoid spurious failures. Fixes bug 27295; bugfix on 0.2.7.3-rc. Changes in version 0.3.4.7-rc - 2018-08-24 Tor 0.3.4.7-rc fixes several small compilation, portability, and correctness issues in previous versions of Tor. This version is a release candidate: if no serious bugs are found, we expect that the stable 0.3.4 release will be (almost) the same as this release. o Minor features (bug workaround): - Compile correctly on systems that provide the C11 stdatomic.h header, but where C11 atomic functions don't actually compile. Closes ticket 26779; workaround for Debian issue 903709. o Minor features (continuous integration): - Backport Travis rust distcheck to 0.3.3. Closes ticket 24629. - Enable macOS builds in our Travis CI configuration. Closes ticket 24629. - Install libcap-dev and libseccomp2-dev so these optional dependencies get tested on Travis CI. Closes ticket 26560. - Only post Appveyor IRC notifications when the build fails. Implements ticket 27275. - Run asciidoc during Travis CI. Implements ticket 27087. - Use ccache in our Travis CI configuration. Closes ticket 26952. o Minor features (continuous integration, rust): - Use cargo cache in our Travis CI configuration. Closes ticket 26952. o Minor features (directory authorities): - Authorities no longer vote to make the subprotocol version "LinkAuth=1" a requirement: it is unsupportable with NSS, and hasn't been needed since Tor 0.3.0.1-alpha. Closes ticket 27286. o Minor features (geoip): - Update geoip and geoip6 to the August 7 2018 Maxmind GeoLite2 Country database. Closes ticket 27089. o Minor bugfixes (compilation, windows): - Don't link or search for pthreads when building for Windows, even if we are using build environment (like mingw) that provides a pthreads library. Fixes bug 27081; bugfix on 0.1.0.1-rc. o Minor bugfixes (continuous integration): - Improve Appveyor CI IRC logging. Generate correct branches and URLs for pull requests and tags. Use unambiguous short commits. Fixes bug 26979; bugfix on master. - Build with zstd on macOS. Fixes bug 27090; bugfix on 0.3.1.5-alpha. - Pass the module flags to distcheck configure, and log the flags before running configure. (Backported to 0.2.9 and later as a precaution.) Fixes bug 27088; bugfix on 0.3.4.1-alpha. o Minor bugfixes (in-process restart): - Always call tor_free_all() when leaving tor_run_main(). When we did not, restarting tor in-process would cause an assertion failure. Fixes bug 26948; bugfix on 0.3.3.1-alpha. o Minor bugfixes (linux seccomp2 sandbox): - Fix a bug in out sandboxing rules for the openat() syscall. Previously, no openat() call would be permitted, which would break filesystem operations on recent glibc versions. Fixes bug 25440; bugfix on 0.2.9.15. Diagnosis and patch from Daniel Pinto. o Minor bugfixes (onion services): - Fix bug that causes services to not ever rotate their descriptors if they were getting SIGHUPed often. Fixes bug 26932; bugfix on 0.3.2.1-alpha. o Minor bugfixes (portability): - Fix compilation of the unit tests on GNU/Hurd, which does not define PATH_MAX. Fixes bug 26873; bugfix on 0.3.3.1-alpha. Patch from "paulusASol". o Minor bugfixes (rust): - Backport test_rust.sh from master. Fixes bug 26497; bugfix on 0.3.1.5-alpha. - Consistently use ../../.. as a fallback for $abs_top_srcdir in test_rust.sh. Fixes bug 27093; bugfix on 0.3.4.3-alpha. - Protover parsing was accepting the presence of whitespace in version strings, which the C implementation would choke on, e.g. "Desc=1\t,2". Fixes bug 27177; bugfix on 0.3.3.5-rc. - Protover parsing was ignoring a 2nd hyphen and everything after it, accepting entries like "Link=1-5-foo". Fixes bug 27164; bugfix on 0.3.3.1-alpha. - Stop setting $CARGO_HOME. cargo will use the user's $CARGO_HOME, or $HOME/.cargo by default. Fixes bug 26497; bugfix on 0.3.1.5-alpha. - cd to ${abs_top_builddir}/src/rust before running cargo in src/test/test_rust.sh. This makes the working directory consistent between builds and tests. Fixes bug 26497; bugfix on 0.3.3.2-alpha. o Minor bugfixes (testing, bootstrap): - When calculating bootstrap progress, check exit policies and the exit flag. Previously, Tor would only check the exit flag, which caused race conditions in small and fast networks like chutney. Fixes bug 27236; bugfix on 0.2.6.3-alpha. o Minor bugfixes (testing, openssl compatibility): - Our "tortls/cert_matches_key" unit test no longer relies on OpenSSL internals. Previously, it relied on unsupported OpenSSL behavior in a way that caused it to crash with OpenSSL 1.0.2p. Fixes bug 27226; bugfix on 0.2.5.1-alpha. o Minor bugfixes (Windows, compilation): - Silence a compilation warning on MSVC 2017 and clang-cl. Fixes bug 27185; bugfix on 0.2.2.2-alpha. Changes in version 0.3.4.6-rc - 2018-08-06 Tor 0.3.4.6-rc fixes several small compilation, portability, and correctness issues in previous versions of Tor. This version is a release candidate: if no serious bugs are found, we expect that the stable 0.3.4 release will be (almost) the same as this release. o Major bugfixes (event scheduler): - When we enable a periodic event, schedule it in the event loop rather than running it immediately. Previously, we would re-run periodic events immediately in the middle of (for example) changing our options, with unpredictable effects. Fixes bug 27003; bugfix on 0.3.4.1-alpha. o Minor features (compilation): - When building Tor, prefer to use Python 3 over Python 2, and more recent (contemplated) versions over older ones. Closes ticket 26372. - When compiling with --enable-openbsd-malloc or --enable-tcmalloc, tell the compiler not to include the system malloc implementation. Fixes bug 20424; bugfix on 0.2.0.20-rc. - Don't try to use a pragma to temporarily disable the -Wunused-const-variable warning if the compiler doesn't support it. Fixes bug 26785; bugfix on 0.3.2.11. o Minor bugfixes (continuous integration): - Skip a pair of unreliable key generation tests on Windows, until the underlying issue in bug 26076 is resolved. Fixes bug 26830 and bug 26853; bugfix on 0.2.7.3-rc and 0.3.2.1-alpha respectively. o Minor features (controller): - The control port now exposes the list of HTTPTunnelPorts and ExtOrPorts via GETINFO net/listeners/httptunnel and net/listeners/extor respectively. Closes ticket 26647. o Minor bugfixes (directory authority): - When voting for recommended versions, make sure that all of the versions are well-formed and parsable. Fixes bug 26485; bugfix on 0.1.1.6-alpha. o Minor features (geoip): - Update geoip and geoip6 to the July 3 2018 Maxmind GeoLite2 Country database. Closes ticket 26674. o Minor features (Rust, portability): - Rust cross-compilation is now supported. Closes ticket 25895. o Minor bugfixes (compilation): - Update build system so that tor builds again with --disable-unittests after recent refactoring. Fixes bug 26789; bugfix on 0.3.4.3-alpha. - Fix a compilation warning on some versions of GCC when building code that calls routerinfo_get_my_routerinfo() twice, assuming that the second call will succeed if the first one did. Fixes bug 26269; bugfix on 0.2.8.2-alpha. o Minor bugfixes (controller): - Report the port correctly when a port is configured to bind to "auto". Fixes bug 26568; bugfix on 0.3.4.1-alpha. - Parse the "HSADDRESS=" parameter in HSPOST commands properly. Previously, it was misparsed and ignored. Fixes bug 26523; bugfix on 0.3.3.1-alpha. Patch by "akwizgran". o Minor bugfixes (correctness, flow control): - Upon receiving a stream-level SENDME cell, verify that our window has not grown too large. Fixes bug 26214; bugfix on svn r54 (pre-0.0.1). o Minor bugfixes (memory, correctness): - Fix a number of small memory leaks identified by coverity. Fixes bug 26467; bugfix on numerous Tor versions. o Minor bugfixes (logging): - Improve the log message when connection initiators fail to authenticate direct connections to relays. Fixes bug 26927; bugfix on 0.3.0.1-alpha. o Minor bugfixes (portability): - Avoid a compilation error in test_bwmgt.c on Solaris 10. Fixes bug 26994; bugfix on 0.3.4.1-alpha. - Work around two different bugs in the OS X 10.10 and later SDKs that would prevent us from successfully targeting earlier versions of OS X. Fixes bug 26876; bugfix on 0.3.3.1-alpha. o Minor bugfixes (single onion services, Tor2web): - Log a protocol warning when single onion services or Tor2web clients fail to authenticate direct connections to relays. Fixes bug 26924; bugfix on 0.2.9.1-alpha. o Minor bugfixes (testing): - Disable core dumps in test_bt.sh, to avoid failures in "make distcheck". Fixes bug 26787; bugfix on 0.2.5.2-alpha. o Minor bugfixes (testing, compatibility): - When running the ntor_ref.py and hs_ntor_ref.py tests, make sure only to pass strings (rather than "bytes" objects) to the Python subprocess module. Python 3 on Windows seems to require this. Fixes bug 26535; bugfix on 0.2.5.5-alpha (for ntor_ref.py) and 0.3.1.1-alpha (for hs_ntor_ref.py). o Minor bugfixes (v3 onion services): - Stop sending ed25519 link specifiers in v3 onion service introduce cells and descriptors, when the rendezvous or introduction point doesn't support ed25519 link authentication. Fixes bug 26627; bugfix on 0.3.2.4-alpha. Changes in version 0.3.4.5-rc - 2018-07-13 Tor 0.3.4.5-rc moves to a new bridge authority, meaning people running bridge relays should upgrade. o Directory authority changes: - The "Bifroest" bridge authority has been retired; the new bridge authority is "Serge", and it is operated by George from the TorBSD project. Closes ticket 26771. Changes in version 0.3.3.9 - 2018-07-13 Tor 0.3.3.9 moves to a new bridge authority, meaning people running bridge relays should upgrade. o Directory authority changes: - The "Bifroest" bridge authority has been retired; the new bridge authority is "Serge", and it is operated by George from the TorBSD project. Closes ticket 26771. Changes in version 0.3.2.11 - 2018-07-13 Tor 0.3.2.11 moves to a new bridge authority, meaning people running bridge relays should upgrade. We also take this opportunity to backport other minor fixes. o Directory authority changes: - The "Bifroest" bridge authority has been retired; the new bridge authority is "Serge", and it is operated by George from the TorBSD project. Closes ticket 26771. o Directory authority changes (backport from 0.3.3.7): - Add an IPv6 address for the "dannenberg" directory authority. Closes ticket 26343. o Major bugfixes (directory authorities, backport from 0.3.4.1-alpha): - When directory authorities read a zero-byte bandwidth file, they would previously log a warning with the contents of an uninitialised buffer. They now log a warning about the empty file instead. Fixes bug 26007; bugfix on 0.2.2.1-alpha. o Major bugfixes (onion service, backport from 0.3.4.1-alpha): - Correctly detect when onion services get disabled after HUP. Fixes bug 25761; bugfix on 0.3.2.1. o Minor features (sandbox, backport from 0.3.3.4-alpha): - Explicitly permit the poll() system call when the Linux seccomp2-based sandbox is enabled: apparently, some versions of libc use poll() when calling getpwnam(). Closes ticket 25313. o Minor feature (continuous integration, backport from 0.3.3.5-rc): - Update the Travis CI configuration to use the stable Rust channel, now that we have decided to require that. Closes ticket 25714. o Minor features (continuous integration, backport from 0.3.4.1-alpha): - Our .travis.yml configuration now includes support for testing the results of "make distcheck". (It's not uncommon for "make check" to pass but "make distcheck" to fail.) Closes ticket 25814. - Our Travis CI configuration now integrates with the Coveralls coverage analysis tool. Closes ticket 25818. o Minor features (relay, diagnostic, backport from 0.3.4.3-alpha): - Add several checks to detect whether Tor relays are uploading their descriptors without specifying why they regenerated them. Diagnostic for ticket 25686. o Minor features (compilation, backport from 0.3.4.4-rc): - When building Tor, prefer to use Python 3 over Python 2, and more recent (contemplated) versions over older ones. Closes ticket 26372. o Minor features (geoip): - Update geoip and geoip6 to the July 3 2018 Maxmind GeoLite2 Country database. Closes ticket 26674. o Minor bugfixes (correctness, client, backport from 0.3.4.1-alpha): - Upon receiving a malformed connected cell, stop processing the cell immediately. Previously we would mark the connection for close, but continue processing the cell as if the connection were open. Fixes bug 26072; bugfix on 0.2.4.7-alpha. o Minor bugfixes (Linux seccomp2 sandbox, backport from 0.3.4.1-alpha): - Allow the nanosleep() system call, which glibc uses to implement sleep() and usleep(). Fixes bug 24969; bugfix on 0.2.5.1-alpha. o Minor bugfixes (testing, compatibility, backport from 0.3.4.4-rc): - When running the hs_ntor_ref.py test, make sure only to pass strings (rather than "bytes" objects) to the Python subprocess module. Python 3 on Windows seems to require this. Fixes bug 26535; bugfix on 0.3.1.1-alpha. - When running the ntor_ref.py test, make sure only to pass strings (rather than "bytes" objects) to the Python subprocess module. Python 3 on Windows seems to require this. Fixes bug 26535; bugfix on 0.2.5.5-alpha. o Minor bugfixes (compatibility, openssl, backport from 0.3.4.2-alpha): - Work around a change in OpenSSL 1.1.1 where return values that would previously indicate "no password" now indicate an empty password. Without this workaround, Tor instances running with OpenSSL 1.1.1 would accept descriptors that other Tor instances would reject. Fixes bug 26116; bugfix on 0.2.5.16. o Minor bugfixes (documentation, backport from 0.3.3.5-rc): - Document that the PerConnBW{Rate,Burst} options will fall back to their corresponding consensus parameters only if those parameters are set. Previously we had claimed that these values would always be set in the consensus. Fixes bug 25296; bugfix on 0.2.2.7-alpha. o Minor bugfixes (compilation, backport from 0.3.4.4-rc): - Fix a compilation warning on some versions of GCC when building code that calls routerinfo_get_my_routerinfo() twice, assuming that the second call will succeed if the first one did. Fixes bug 26269; bugfix on 0.2.8.2-alpha. o Minor bugfixes (client, backport from 0.3.4.1-alpha): - Don't consider Tor running as a client if the ControlPort is open, but no actual client ports are open. Fixes bug 26062; bugfix on 0.2.9.4-alpha. o Minor bugfixes (hardening, backport from 0.3.4.2-alpha): - Prevent a possible out-of-bounds smartlist read in protover_compute_vote(). Fixes bug 26196; bugfix on 0.2.9.4-alpha. o Minor bugfixes (C correctness, backport from 0.3.3.4-alpha): - Fix a very unlikely (impossible, we believe) null pointer dereference. Fixes bug 25629; bugfix on 0.2.9.15. Found by Coverity; this is CID 1430932. o Minor bugfixes (onion service, backport from 0.3.4.1-alpha): - Fix a memory leak when a v3 onion service is configured and gets a SIGHUP signal. Fixes bug 25901; bugfix on 0.3.2.1-alpha. - When parsing the descriptor signature, look for the token plus an extra white-space at the end. This is more correct but also will allow us to support new fields that might start with "signature". Fixes bug 26069; bugfix on 0.3.0.1-alpha. o Minor bugfixes (relay, backport from 0.3.4.3-alpha): - Relays now correctly block attempts to re-extend to the previous relay by Ed25519 identity. Previously they would warn in this case, but not actually reject the attempt. Fixes bug 26158; bugfix on 0.3.0.1-alpha. o Minor bugfixes (relay, crash, backport from 0.3.4.1-alpha): - Avoid a crash when running with DirPort set but ORPort turned off. Fixes a case of bug 23693; bugfix on 0.3.1.1-alpha. o Minor bugfixes (compilation, backport from 0.3.4.2-alpha): - Silence unused-const-variable warnings in zstd.h with some GCC versions. Fixes bug 26272; bugfix on 0.3.1.1-alpha. o Minor bugfixes (testing, backport from 0.3.3.4-alpha): - Avoid intermittent test failures due to a test that had relied on onion service introduction point creation finishing within 5 seconds of real clock time. Fixes bug 25450; bugfix on 0.3.1.3-alpha. o Minor bugfixes (compilation, backport from 0.3.3.4-alpha): - Fix a C99 compliance issue in our configuration script that caused compilation issues when compiling Tor with certain versions of xtools. Fixes bug 25474; bugfix on 0.3.2.5-alpha. o Minor bugfixes (memory, correctness, backport from 0.3.4.4-rc): - Fix a number of small memory leaks identified by coverity. Fixes bug 26467; bugfix on numerous Tor versions. o Code simplification and refactoring (backport from 0.3.3.5-rc): - Move the list of default directory authorities to its own file. Closes ticket 24854. Patch by "beastr0". Changes in version 0.2.9.16 - 2018-07-13 Tor 0.2.9.16 moves to a new bridge authority, meaning people running bridge relays should upgrade. We also take this opportunity to backport other minor fixes. o Directory authority changes: - The "Bifroest" bridge authority has been retired; the new bridge authority is "Serge", and it is operated by George from the TorBSD project. Closes ticket 26771. o Directory authority changes (backport from 0.3.3.7): - Add an IPv6 address for the "dannenberg" directory authority. Closes ticket 26343. o Major bugfixes (directory authorities, backport from 0.3.4.1-alpha): - When directory authorities read a zero-byte bandwidth file, they would previously log a warning with the contents of an uninitialised buffer. They now log a warning about the empty file instead. Fixes bug 26007; bugfix on 0.2.2.1-alpha. o Minor features (sandbox, backport from 0.3.3.4-alpha): - Explicitly permit the poll() system call when the Linux seccomp2-based sandbox is enabled: apparently, some versions of libc use poll() when calling getpwnam(). Closes ticket 25313. o Minor features (continuous integration, backport from 0.3.4.1-alpha): - Our .travis.yml configuration now includes support for testing the results of "make distcheck". (It's not uncommon for "make check" to pass but "make distcheck" to fail.) Closes ticket 25814. - Our Travis CI configuration now integrates with the Coveralls coverage analysis tool. Closes ticket 25818. o Minor features (compilation, backport from 0.3.4.4-rc): - When building Tor, prefer to use Python 3 over Python 2, and more recent (contemplated) versions over older ones. Closes ticket 26372. o Minor features (geoip): - Update geoip and geoip6 to the July 3 2018 Maxmind GeoLite2 Country database. Closes ticket 26674. o Minor bugfixes (correctness, client, backport from 0.3.4.1-alpha): - Upon receiving a malformed connected cell, stop processing the cell immediately. Previously we would mark the connection for close, but continue processing the cell as if the connection were open. Fixes bug 26072; bugfix on 0.2.4.7-alpha. o Minor bugfixes (Linux seccomp2 sandbox, backport from 0.3.4.1-alpha): - Allow the nanosleep() system call, which glibc uses to implement sleep() and usleep(). Fixes bug 24969; bugfix on 0.2.5.1-alpha. o Minor bugfixes (testing, compatibility, backport from 0.3.4.4-rc): - When running the ntor_ref.py test, make sure only to pass strings (rather than "bytes" objects) to the Python subprocess module. Python 3 on Windows seems to require this. Fixes bug 26535; bugfix on 0.2.5.5-alpha. o Minor bugfixes (compatibility, openssl, backport from 0.3.4.2-alpha): - Work around a change in OpenSSL 1.1.1 where return values that would previously indicate "no password" now indicate an empty password. Without this workaround, Tor instances running with OpenSSL 1.1.1 would accept descriptors that other Tor instances would reject. Fixes bug 26116; bugfix on 0.2.5.16. o Minor bugfixes (compilation, backport from 0.3.4.4-rc): - Fix a compilation warning on some versions of GCC when building code that calls routerinfo_get_my_routerinfo() twice, assuming that the second call will succeed if the first one did. Fixes bug 26269; bugfix on 0.2.8.2-alpha. o Minor bugfixes (client, backport from 0.3.4.1-alpha): - Don't consider Tor running as a client if the ControlPort is open, but no actual client ports are open. Fixes bug 26062; bugfix on 0.2.9.4-alpha. o Minor bugfixes (hardening, backport from 0.3.4.2-alpha): - Prevent a possible out-of-bounds smartlist read in protover_compute_vote(). Fixes bug 26196; bugfix on 0.2.9.4-alpha. o Minor bugfixes (C correctness, backport from 0.3.3.4-alpha): - Fix a very unlikely (impossible, we believe) null pointer dereference. Fixes bug 25629; bugfix on 0.2.9.15. Found by Coverity; this is CID 1430932. o Minor bugfixes (memory, correctness, backport from 0.3.4.4-rc): - Fix a number of small memory leaks identified by coverity. Fixes bug 26467; bugfix on numerous Tor versions. o Code simplification and refactoring (backport from 0.3.3.5-rc): - Move the list of default directory authorities to its own file. Closes ticket 24854. Patch by "beastr0". Changes in version 0.3.4.4-rc - 2018-07-09 Tor 0.3.4.4-rc fixes several small compilation, portability, and correctness issues in previous versions of Tor. This version is a release candidate: if no serious bugs are found, we expect that the stable 0.3.4 release will be (almost) the same as this release. o Minor features (compilation): - When building Tor, prefer to use Python 3 over Python 2, and more recent (contemplated) versions over older ones. Closes ticket 26372. o Minor features (geoip): - Update geoip and geoip6 to the July 3 2018 Maxmind GeoLite2 Country database. Closes ticket 26674. o Minor features (Rust, portability): - Rust cross-compilation is now supported. Closes ticket 25895. o Minor bugfixes (compilation): - Fix a compilation warning on some versions of GCC when building code that calls routerinfo_get_my_routerinfo() twice, assuming that the second call will succeed if the first one did. Fixes bug 26269; bugfix on 0.2.8.2-alpha. o Minor bugfixes (control port): - Report the port correctly when a port is configured to bind to "auto". Fixes bug 26568; bugfix on 0.3.4.1-alpha. - Handle the HSADDRESS= argument to the HSPOST command properly. (Previously, this argument was misparsed and thus ignored.) Fixes bug 26523; bugfix on 0.3.3.1-alpha. Patch by "akwizgran". o Minor bugfixes (correctness, flow control): - Upon receiving a stream-level SENDME cell, verify that our window has not grown too large. Fixes bug 26214; bugfix on svn r54 (pre-0.0.1). o Minor bugfixes (memory, correctness): - Fix a number of small memory leaks identified by coverity. Fixes bug 26467; bugfix on numerous Tor versions. o Minor bugfixes (testing, compatibility): - When running the hs_ntor_ref.py test, make sure only to pass strings (rather than "bytes" objects) to the Python subprocess module. Python 3 on Windows seems to require this. Fixes bug 26535; bugfix on 0.3.1.1-alpha. - When running the ntor_ref.py test, make sure only to pass strings (rather than "bytes" objects) to the Python subprocess module. Python 3 on Windows seems to require this. Fixes bug 26535; bugfix on 0.2.5.5-alpha. Changes in version 0.3.3.8 - 2018-07-09 Tor 0.3.3.8 backports several changes from the 0.3.4.x series, including fixes for a memory leak affecting directory authorities. o Major bugfixes (directory authority, backport from 0.3.4.3-alpha): - Stop leaking memory on directory authorities when planning to vote. This bug was crashing authorities by exhausting their memory. Fixes bug 26435; bugfix on 0.3.3.6. o Major bugfixes (rust, testing, backport from 0.3.4.3-alpha): - Make sure that failing tests in Rust will actually cause the build to fail: previously, they were ignored. Fixes bug 26258; bugfix on 0.3.3.4-alpha. o Minor features (compilation, backport from 0.3.4.4-rc): - When building Tor, prefer to use Python 3 over Python 2, and more recent (contemplated) versions over older ones. Closes ticket 26372. o Minor features (geoip): - Update geoip and geoip6 to the July 3 2018 Maxmind GeoLite2 Country database. Closes ticket 26674. o Minor features (relay, diagnostic, backport from 0.3.4.3-alpha): - Add several checks to detect whether Tor relays are uploading their descriptors without specifying why they regenerated them. Diagnostic for ticket 25686. o Minor bugfixes (circuit path selection, backport from 0.3.4.1-alpha): - Don't count path selection failures as circuit build failures. This change should eliminate cases where Tor blames its guard or the network for situations like insufficient microdescriptors and/or overly restrictive torrc settings. Fixes bug 25705; bugfix on 0.3.3.1-alpha. o Minor bugfixes (compilation, backport from 0.3.4.4-rc): - Fix a compilation warning on some versions of GCC when building code that calls routerinfo_get_my_routerinfo() twice, assuming that the second call will succeed if the first one did. Fixes bug 26269; bugfix on 0.2.8.2-alpha. o Minor bugfixes (control port, backport from 0.3.4.4-rc): - Handle the HSADDRESS= argument to the HSPOST command properly. (Previously, this argument was misparsed and thus ignored.) Fixes bug 26523; bugfix on 0.3.3.1-alpha. Patch by "akwizgran". o Minor bugfixes (memory, correctness, backport from 0.3.4.4-rc): - Fix a number of small memory leaks identified by coverity. Fixes bug 26467; bugfix on numerous Tor versions. o Minor bugfixes (relay, backport from 0.3.4.3-alpha): - Relays now correctly block attempts to re-extend to the previous relay by Ed25519 identity. Previously they would warn in this case, but not actually reject the attempt. Fixes bug 26158; bugfix on 0.3.0.1-alpha. o Minor bugfixes (restart-in-process, backport from 0.3.4.1-alpha): - When shutting down, Tor now clears all the flags in the control.c module. This should prevent a bug where authentication cookies are not generated on restart. Fixes bug 25512; bugfix on 0.3.3.1-alpha. o Minor bugfixes (testing, compatibility, backport from 0.3.4.4-rc): - When running the hs_ntor_ref.py test, make sure only to pass strings (rather than "bytes" objects) to the Python subprocess module. Python 3 on Windows seems to require this. Fixes bug 26535; bugfix on 0.3.1.1-alpha. - When running the ntor_ref.py test, make sure only to pass strings (rather than "bytes" objects) to the Python subprocess module. Python 3 on Windows seems to require this. Fixes bug 26535; bugfix on 0.2.5.5-alpha. Changes in version 0.3.4.3-alpha - 2018-06-26 Tor 0.3.4.3-alpha fixes several bugs in earlier versions, including one that was causing stability issues on directory authorities. o Major bugfixes (directory authority): - Stop leaking memory on directory authorities when planning to vote. This bug was crashing authorities by exhausting their memory. Fixes bug 26435; bugfix on 0.3.3.6. o Major bugfixes (rust, testing): - Make sure that failing tests in Rust will actually cause the build to fail: previously, they were ignored. Fixes bug 26258; bugfix on 0.3.3.4-alpha. o Minor feature (directory authorities): - Stop warning about incomplete bw lines before the first complete bw line has been found, so that additional header lines can be ignored. Fixes bug 25960; bugfix on 0.2.2.1-alpha o Minor features (relay, diagnostic): - Add several checks to detect whether Tor relays are uploading their descriptors without specifying why they regenerated them. Diagnostic for ticket 25686. o Minor features (unit tests): - Test complete bandwidth measurements files, and test that incomplete bandwidth lines only give warnings when the end of the header has not been detected. Fixes bug 25947; bugfix on 0.2.2.1-alpha o Minor bugfixes (compilation): - Refrain from compiling unit testing related object files when --disable-unittests is set to configure script. Fixes bug 24891; bugfix on 0.2.5.1-alpha. - When linking the libtor_testing.a library, only include the dirauth object files once. Previously, they were getting added twice. Fixes bug 26402; bugfix on 0.3.4.1-alpha. - The --enable-fatal-warnings flag now affects Rust code as well. Closes ticket 26245. o Minor bugfixes (onion services): - Recompute some consensus information after detecting a clock jump, or after transitioning from a non-live consensus to a live consensus. We do this to avoid having an outdated state, and miscalculating the index for next-generation onion services. Fixes bug 24977; bugfix on 0.3.2.1-alpha. o Minor bugfixes (relay): - Relays now correctly block attempts to re-extend to the previous relay by Ed25519 identity. Previously they would warn in this case, but not actually reject the attempt. Fixes bug 26158; bugfix on 0.3.0.1-alpha. o Minor bugfixes (testing): - Fix compilation of the doctests in the Rust crypto crate. Fixes bug 26415; bugfix on 0.3.4.1-alpha. - Instead of trying to read the geoip configuration files from within the unit tests, instead create our own ersatz files with just enough geoip data in the format we expect. Trying to read from the source directory created problems on Windows with mingw, where the build system's paths are not the same as the platform's paths. Fixes bug 25787; bugfix on 0.3.4.1-alpha. - Refrain from trying to get an item from an empty smartlist in test_bridges_clear_bridge_list. Set DEBUG_SMARTLIST in unit tests to catch improper smartlist usage. Furthermore, enable DEBUG_SMARTLIST globally when build is configured with fragile hardening. Fixes bug 26196; bugfix on 0.3.4.1-alpha. Changes in version 0.3.3.7 - 2018-06-12 Tor 0.3.3.7 backports several changes from the 0.3.4.x series, including fixes for bugs affecting compatibility and stability. o Directory authority changes: - Add an IPv6 address for the "dannenberg" directory authority. Closes ticket 26343. o Minor features (geoip): - Update geoip and geoip6 to the June 7 2018 Maxmind GeoLite2 Country database. Closes ticket 26351. o Minor bugfixes (compatibility, openssl, backport from 0.3.4.2-alpha): - Work around a change in OpenSSL 1.1.1 where return values that would previously indicate "no password" now indicate an empty password. Without this workaround, Tor instances running with OpenSSL 1.1.1 would accept descriptors that other Tor instances would reject. Fixes bug 26116; bugfix on 0.2.5.16. o Minor bugfixes (compilation, backport from 0.3.4.2-alpha): - Silence unused-const-variable warnings in zstd.h with some GCC versions. Fixes bug 26272; bugfix on 0.3.1.1-alpha. o Minor bugfixes (controller, backport from 0.3.4.2-alpha): - Improve accuracy of the BUILDTIMEOUT_SET control port event's TIMEOUT_RATE and CLOSE_RATE fields. (We were previously miscounting the total number of circuits for these field values.) Fixes bug 26121; bugfix on 0.3.3.1-alpha. o Minor bugfixes (hardening, backport from 0.3.4.2-alpha): - Prevent a possible out-of-bounds smartlist read in protover_compute_vote(). Fixes bug 26196; bugfix on 0.2.9.4-alpha. o Minor bugfixes (path selection, backport from 0.3.4.1-alpha): - Only select relays when they have the descriptors we prefer to use for them. This change fixes a bug where we could select a relay because it had _some_ descriptor, but reject it later with a nonfatal assertion error because it didn't have the exact one we wanted. Fixes bugs 25691 and 25692; bugfix on 0.3.3.4-alpha. Changes in version 0.3.4.2-alpha - 2018-06-12 Tor 0.3.4.2-alpha fixes several minor bugs in the previous alpha release, and forward-ports an authority-only security fix from 0.3.3.6. o Directory authority changes: - Add an IPv6 address for the "dannenberg" directory authority. Closes ticket 26343. o Major bugfixes (security, directory authority, denial-of-service, also in 0.3.3.6): - Fix a bug that could have allowed an attacker to force a directory authority to use up all its RAM by passing it a maliciously crafted protocol versions string. Fixes bug 25517; bugfix on 0.2.9.4-alpha. This issue is also tracked as TROVE-2018-005. o Minor features (continuous integration): - Add the necessary configuration files for continuous integration testing on Windows, via the Appveyor platform. Closes ticket 25549. Patches from Marcin Cieślak and Isis Lovecruft. o Minor features (geoip): - Update geoip and geoip6 to the June 7 2018 Maxmind GeoLite2 Country database. Closes ticket 26351. o Minor bugfixes (compatibility, openssl): - Work around a change in OpenSSL 1.1.1 where return values that would previously indicate "no password" now indicate an empty password. Without this workaround, Tor instances running with OpenSSL 1.1.1 would accept descriptors that other Tor instances would reject. Fixes bug 26116; bugfix on 0.2.5.16. o Minor bugfixes (compilation): - Silence unused-const-variable warnings in zstd.h with some GCC versions. Fixes bug 26272; bugfix on 0.3.1.1-alpha. - Fix compilation when using OpenSSL 1.1.0 with the "no-deprecated" flag enabled. Fixes bug 26156; bugfix on 0.3.4.1-alpha. - Avoid a compiler warning when casting the return value of smartlist_len() to double with DEBUG_SMARTLIST enabled. Fixes bug 26283; bugfix on 0.2.4.10-alpha. o Minor bugfixes (control port): - Do not count 0-length RELAY_COMMAND_DATA cells as valid data in CIRC_BW events. Previously, such cells were counted entirely in the OVERHEAD field. Now they are not. Fixes bug 26259; bugfix on 0.3.4.1-alpha. o Minor bugfixes (controller): - Improve accuracy of the BUILDTIMEOUT_SET control port event's TIMEOUT_RATE and CLOSE_RATE fields. (We were previously miscounting the total number of circuits for these field values.) Fixes bug 26121; bugfix on 0.3.3.1-alpha. o Minor bugfixes (hardening): - Prevent a possible out-of-bounds smartlist read in protover_compute_vote(). Fixes bug 26196; bugfix on 0.2.9.4-alpha. o Minor bugfixes (onion services): - Fix a bug that blocked the creation of ephemeral v3 onion services. Fixes bug 25939; bugfix on 0.3.4.1-alpha. o Minor bugfixes (test coverage tools): - Update our "cov-diff" script to handle output from the latest version of gcov, and to remove extraneous timestamp information from its output. Fixes bugs 26101 and 26102; bugfix on 0.2.5.1-alpha. Changes in version 0.3.3.6 - 2018-05-22 Tor 0.3.3.6 is the first stable release in the 0.3.3 series. It backports several important fixes from the 0.3.4.1-alpha. The Tor 0.3.3 series includes controller support and other improvements for v3 onion services, official support for embedding Tor within other applications, and our first non-trivial module written in the Rust programming language. (Rust is still not enabled by default when building Tor.) And as usual, there are numerous other smaller bugfixes, features, and improvements. Below are the changes since 0.3.3.5-rc. For a list of all changes since 0.3.2.10, see the ReleaseNotes file. o Major bugfixes (directory authorities, security, backport from 0.3.4.1-alpha): - When directory authorities read a zero-byte bandwidth file, they would previously log a warning with the contents of an uninitialised buffer. They now log a warning about the empty file instead. Fixes bug 26007; bugfix on 0.2.2.1-alpha. o Major bugfixes (security, directory authority, denial-of-service): - Fix a bug that could have allowed an attacker to force a directory authority to use up all its RAM by passing it a maliciously crafted protocol versions string. Fixes bug 25517; bugfix on 0.2.9.4-alpha. This issue is also tracked as TROVE-2018-005. o Major bugfixes (crash, backport from 0.3.4.1-alpha): - Avoid a rare assertion failure in the circuit build timeout code if we fail to allow any circuits to actually complete. Fixes bug 25733; bugfix on 0.2.2.2-alpha. o Major bugfixes (directory authorities, backport from 0.3.4.1-alpha): - Avoid a crash when testing router reachability on a router that could have an ed25519 ID, but which does not. Fixes bug 25415; bugfix on 0.3.3.2-alpha. o Major bugfixes (onion service, backport from 0.3.4.1-alpha): - Correctly detect when onion services get disabled after HUP. Fixes bug 25761; bugfix on 0.3.2.1. o Major bugfixes (relay, denial of service, backport from 0.3.4.1-alpha): - Impose a limit on circuit cell queue size. The limit can be controlled by a consensus parameter. Fixes bug 25226; bugfix on 0.2.4.14-alpha. o Minor features (compatibility, backport from 0.3.4.1-alpha): - Avoid some compilation warnings with recent versions of LibreSSL. Closes ticket 26006. o Minor features (continuous integration, backport from 0.3.4.1-alpha): - Our .travis.yml configuration now includes support for testing the results of "make distcheck". (It's not uncommon for "make check" to pass but "make distcheck" to fail.) Closes ticket 25814. - Our Travis CI configuration now integrates with the Coveralls coverage analysis tool. Closes ticket 25818. o Minor features (geoip): - Update geoip and geoip6 to the May 1 2018 Maxmind GeoLite2 Country database. Closes ticket 26104. o Minor bugfixes (client, backport from 0.3.4.1-alpha): - Don't consider Tor running as a client if the ControlPort is open, but no actual client ports are open. Fixes bug 26062; bugfix on 0.2.9.4-alpha. o Minor bugfixes (correctness, client, backport from 0.3.4.1-alpha): - Upon receiving a malformed connected cell, stop processing the cell immediately. Previously we would mark the connection for close, but continue processing the cell as if the connection were open. Fixes bug 26072; bugfix on 0.2.4.7-alpha. o Minor bugfixes (documentation, backport from 0.3.4.1-alpha): - Stop saying in the manual that clients cache ipv4 dns answers from exit relays. We haven't used them since 0.2.6.3-alpha, and in ticket 24050 we stopped even caching them as of 0.3.2.6-alpha, but we forgot to say so in the man page. Fixes bug 26052; bugfix on 0.3.2.6-alpha. o Minor bugfixes (Linux seccomp2 sandbox, backport from 0.3.4.1-alpha): - Allow the nanosleep() system call, which glibc uses to implement sleep() and usleep(). Fixes bug 24969; bugfix on 0.2.5.1-alpha. o Minor bugfixes (onion service, backport from 0.3.4.1-alpha): - Fix a memory leak when a v3 onion service is configured and gets a SIGHUP signal. Fixes bug 25901; bugfix on 0.3.2.1-alpha. - When parsing the descriptor signature, look for the token plus an extra white-space at the end. This is more correct but also will allow us to support new fields that might start with "signature". Fixes bug 26069; bugfix on 0.3.0.1-alpha. o Minor bugfixes (relay, crash, backport from 0.3.4.1-alpha): - Avoid a crash when running with DirPort set but ORPort turned off. Fixes a case of bug 23693; bugfix on 0.3.1.1-alpha. o Documentation (backport from 0.3.4.1-alpha): - Correct an IPv6 error in the documentation for ExitPolicy. Closes ticket 25857. Patch from "CTassisF". Changes in version 0.3.4.1-alpha - 2018-05-17 Tor 0.3.4.1-alpha is the first release in the 0.3.4.x series. It includes refactoring to begin reducing Tor's binary size and idle CPU usage on mobile, along with prep work for new bandwidth scanners, improvements to the experimental "vanguards" feature, and numerous other small features and bugfixes. o New system requirements: - Tor no longer tries to support old operating systems without mmap() or some local equivalent. Apparently, compilation on such systems has been broken for some time, without anybody noticing or complaining. Closes ticket 25398. o Major feature (directory authority, modularization): - The directory authority subsystem has been modularized. The code is now located in src/or/dirauth/, and is compiled in by default. To disable the module, the configure option --disable-module-dirauth has been added. This module may be disabled by default in some future release. Closes ticket 25610. o Major features (main loop, CPU usage): - When Tor is disabled (via DisableNetwork or via hibernation), it no longer needs to run any per-second events. This change should make it easier for mobile applications to disable Tor while the device is sleeping, or Tor is not running. Closes ticket 26063. - Tor no longer enables all of its periodic events by default. Previously, Tor would enable all possible main loop events, regardless of whether it needed them. Furthermore, many of these events are now disabled with Tor is hibernating or DisableNetwork is set. This is a big step towards reducing client CPU usage by reducing the amount of wake-ups the daemon does. Closes ticket 25376 and 25762. - The bandwidth-limitation logic has been refactored so that bandwidth calculations are performed on-demand, rather than every TokenBucketRefillInterval milliseconds. This change should improve the granularity of our bandwidth calculations, and limit the number of times that the Tor process needs to wake up when it is idle. Closes ticket 25373. - Move responsibility for many operations from a once-per-second callback to a callback that is only scheduled as needed. Moving this functionality has allowed us to disable the callback when Tor's network is disabled. Once enough items are removed from our once-per-second callback, we can eliminate it entirely to conserve CPU when idle. The functionality removed includes: closing connections, circuits, and channels (ticket 25932); consensus voting (25937); flushing log callbacks (25951); honoring delayed SIGNEWNYM requests (25949); rescanning the consensus cache (25931); saving the state file to disk (25948); warning relay operators about unreachable ports (25952); and keeping track of Tor's uptime (26009). o Major bugfixes (directory authorities, security): - When directory authorities read a zero-byte bandwidth file, they would previously log a warning with the contents of an uninitialised buffer. They now log a warning about the empty file instead. Fixes bug 26007; bugfix on 0.2.2.1-alpha. o Major bugfixes (crash): - Avoid a rare assertion failure in the circuit build timeout code if we fail to allow any circuits to actually complete. Fixes bug 25733; bugfix on 0.2.2.2-alpha. o Major bugfixes (directory authority): - Avoid a crash when testing router reachability on a router that could have an ed25519 ID, but which does not. Fixes bug 25415; bugfix on 0.3.3.2-alpha. o Major bugfixes (onion service): - Correctly detect when onion services get disabled after HUP. Fixes bug 25761; bugfix on 0.3.2.1. o Major bugfixes (protover, voting): - Revise Rust implementation of protover to use a more memory- efficient voting algorithm and corresponding data structures, thus avoiding a potential (but small impact) DoS attack where specially crafted protocol strings would expand to several potential megabytes in memory. In the process, several portions of code were revised to be methods on new, custom types, rather than functions taking interchangeable types, thus increasing type safety of the module. Custom error types and handling were added as well, in order to facilitate better error dismissal/handling in outside crates and avoid mistakenly passing an internal error string to C over the FFI boundary. Many tests were added, and some previous differences between the C and Rust implementations have been remedied. Fixes bug 24031; bugfix on 0.3.3.1-alpha. o Major bugfixes (relay, denial of service): - Impose a limit on circuit cell queue size. The limit can be controlled by a consensus parameter. Fixes bug 25226; bugfix on 0.2.4.14-alpha. o Minor features (accounting): - When Tor becomes dormant, it now uses a scheduled event to wake up at the right time. Previously, we would use the per-second timer to check whether to wake up, but we no longer have any per-second timers enabled when the network is disabled. Closes ticket 26064. o Minor features (code quality): - Add optional spell-checking for the Tor codebase, using the "misspell" program. To use this feature, run "make check-typos". Closes ticket 25024. o Minor features (compatibility): - Tor now detects versions of OpenSSL 1.1.0 and later compiled with the no-deprecated option, and builds correctly with them. Closes tickets 19429, 19981, and 25353. - Avoid some compilation warnings with recent versions of LibreSSL. Closes ticket 26006. o Minor features (compression, zstd): - When running with zstd, Tor now considers using advanced functions that the zstd maintainers have labeled as potentially unstable. To prevent breakage, Tor will only use this functionality when the runtime version of the zstd library matches the version with which Tor was compiled. Closes ticket 25162. o Minor features (configuration): - The "DownloadSchedule" options have been renamed to end with "DownloadInitialDelay". The old names are still allowed, but will produce a warning. Comma-separated lists are still permitted for these options, but all values after the first are ignored (as they have been since 0.2.9). Closes ticket 23354. o Minor features (continuous integration): - Our .travis.yml configuration now includes support for testing the results of "make distcheck". (It's not uncommon for "make check" to pass but "make distcheck" to fail.) Closes ticket 25814. - Our Travis CI configuration now integrates with the Coveralls coverage analysis tool. Closes ticket 25818. o Minor features (control port): - Introduce GETINFO "current-time/{local,utc}" to return the local and UTC times respectively in ISO format. This helps a controller like Tor Browser detect a time-related error. Closes ticket 25511. Patch by Neel Chauhan. - Introduce new fields to the CIRC_BW event. There are two new fields in each of the read and written directions. The DELIVERED fields report the total valid data on the circuit, as measured by the payload sizes of verified and error-checked relay command cells. The OVERHEAD fields report the total unused bytes in each of these cells. Closes ticket 25903. o Minor features (directory authority): - Directory authorities now open their key-pinning files as O_SYNC, to limit their chances of accidentally writing partial lines. Closes ticket 23909. o Minor features (directory authority, forward compatibility): - Make the lines of the measured bandwidth file able to contain their entries in any order. Previously, the node_id entry needed to come first. Closes ticket 26004. o Minor features (entry guards): - Introduce a new torrc option NumPrimaryGuards for controlling the number of primary guards. Closes ticket 25843. o Minor features (geoip): - Update geoip and geoip6 to the May 1 2018 Maxmind GeoLite2 Country database. Closes ticket 26104. o Minor features (performance): - Avoid a needless call to malloc() when processing an incoming relay cell. Closes ticket 24914. - Make our timing-wheel code run a tiny bit faster on 32-bit platforms, by preferring 32-bit math to 64-bit. Closes ticket 24688. - Avoid a needless malloc()/free() pair every time we handle an ntor handshake. Closes ticket 25150. o Minor features (testing): - Add a unit test for voting_schedule_get_start_of_next_interval(). Closes ticket 26014, and helps make unit test coverage more deterministic. - A new unittests module specifically for testing the functions in the (new-ish) bridges.c module has been created with new unittests, raising the code coverage percentages. Closes 25425. - We now have improved testing for addressmap_get_virtual_address() function. This should improve our test coverage, and make our test coverage more deterministic. Closes ticket 25993. o Minor features (timekeeping, circuit scheduling): - When keeping track of how busy each circuit have been recently on a given connection, use coarse-grained monotonic timers rather than gettimeofday(). This change should marginally increase accuracy and performance. Implements part of ticket 25927. o Minor bugfixes (bandwidth management): - Consider ourselves "low on write bandwidth" if we have exhausted our write bandwidth some time in the last second. This was the documented behavior before, but the actual behavior was to change this value every TokenBucketRefillInterval. Fixes bug 25828; bugfix on 0.2.3.5-alpha. o Minor bugfixes (C correctness): - Add a missing lock acquisition in the shutdown code of the control subsystem. Fixes bug 25675; bugfix on 0.2.7.3-rc. Found by Coverity; this is CID 1433643. o Minor bugfixes (circuit path selection): - Don't count path selection failures as circuit build failures. This change should eliminate cases where Tor blames its guard or the network for situations like insufficient microdescriptors and/or overly restrictive torrc settings. Fixes bug 25705; bugfix on 0.3.3.1-alpha. o Minor bugfixes (client): - Don't consider Tor running as a client if the ControlPort is open, but no actual client ports are open. Fixes bug 26062; bugfix on 0.2.9.4-alpha. o Minor bugfixes (code style): - Fixed multiple includes of transports.h in src/or/connection.c Fixes bug 25261; bugfix on 0.2.5.1-alpha. - Remove the unused variable n_possible from the function channel_get_for_extend(). Fixes bug 25645; bugfix on 0.2.4.4-alpha o Minor bugfixes (control interface): - Respond with more human-readable error messages to GETINFO exit- policy/* requests. Also, let controller know if an error is transient (response code 551) or not (response code 552). Fixes bug 25852; bugfix on 0.2.8.1-alpha. o Minor bugfixes (controller): - Make CIRC_BW event reflect the total of all data sent on a circuit, including padding and dropped cells. Also fix a mis- counting bug when STREAM_BW events were enabled. Fixes bug 25400; bugfix on 0.2.5.2-alpha. o Minor bugfixes (correctness, client): - Upon receiving a malformed connected cell, stop processing the cell immediately. Previously we would mark the connection for close, but continue processing the cell as if the connection were open. Fixes bug 26072; bugfix on 0.2.4.7-alpha. o Minor bugfixes (directory client): - When unverified-consensus is verified, rename it to cached- consenus. Fixes bug 4187; bugfix on 0.2.0.3-alpha. - Fixed launching a certificate fetch always during the scheduled periodic consensus fetch by fetching only in those cases when consensus are waiting for certs. Fixes bug 24740; bugfix on 0.2.9.1-alpha. o Minor bugfixes (documentation): - Stop saying in the manual that clients cache ipv4 dns answers from exit relays. We haven't used them since 0.2.6.3-alpha, and in ticket 24050 we stopped even caching them as of 0.3.2.6-alpha, but we forgot to say so in the man page. Fixes bug 26052; bugfix on 0.3.2.6-alpha. o Minor bugfixes (error reporting): - Improve tolerance for directory authorities with skewed clocks. Previously, an authority with a clock more than 60 seconds ahead could cause a client with a correct clock to warn that the client's clock was behind. Now the clocks of a majority of directory authorities have to be ahead of the client before this warning will occur. Fixes bug 25756; bugfix on 0.2.2.25-alpha. o Minor bugfixes (Linux seccomp2 sandbox): - Allow the nanosleep() system call, which glibc uses to implement sleep() and usleep(). Fixes bug 24969; bugfix on 0.2.5.1-alpha. o Minor bugfixes (onion service): - Fix a memory leak when a v3 onion service is configured and gets a SIGHUP signal. Fixes bug 25901; bugfix on 0.3.2.1-alpha. - When parsing the descriptor signature, look for the token plus an extra white-space at the end. This is more correct but also will allow us to support new fields that might start with "signature". Fixes bug 26069; bugfix on 0.3.0.1-alpha. o Minor bugfixes (path selection): - Only select relays when they have the descriptors we prefer to use for them. This change fixes a bug where we could select a relay because it had _some_ descriptor, but reject it later with a nonfatal assertion error because it didn't have the exact one we wanted. Fixes bugs 25691 and 25692; bugfix on 0.3.3.4-alpha. o Minor bugfixes (portability): - Do not align mmap length, as it is not required by POSIX, and the getpagesize function is deprecated. Fixes bug 25399; bugfix on 0.1.1.23. o Minor bugfixes (portability, FreeBSD): - In have_enough_mem_for_dircache(), the variable DIRCACHE_MIN_MEM_MB does not stringify on FreeBSD, so we switch to tor_asprintf(). Fixes bug 20887; bugfix on 0.2.8.1-alpha. Patch by Neel Chauhan. o Minor bugfixes (relay statistics): - When a relay is collecting internal statistics about how many create cell requests it has seen of each type, accurately count the requests from relays that temporarily fall out of the consensus. (To be extra conservative, we were already ignoring requests from clients in our counts, and we continue ignoring them here.) Fixes bug 24910; bugfix on 0.2.4.17-rc. o Minor bugfixes (relay, crash): - Avoid a crash when running with DirPort set but ORPort turned off. Fixes a case of bug 23693; bugfix on 0.3.1.1-alpha. o Minor bugfixes (restart-in-process): - When shutting down, Tor now clears all the flags in the control.c module. This should prevent a bug where authentication cookies are not generated on restart. Fixes bug 25512; bugfix on 0.3.3.1-alpha. o Minor bugfixes (testing): - When testing workqueue event-cancellation, make sure that we actually cancel an event, and that cancel each event with equal probability. (It was previously possible, though extremely unlikely, for our event-canceling test not to cancel any events.) Fixes bug 26008; bugfix on 0.2.6.3-alpha. - Repeat part of the test in test_client_pick_intro() a number of times, to give it consistent coverage. Fixes bug 25996; bugfix on 0.3.2.1-alpha. - Remove randomness from the hs_common/responsible_hsdirs test, so that it always takes the same path through the function it tests. Fixes bug 25997; bugfix on 0.3.2.1-alpha. - Change the behavior of the "channel/outbound" test so that it never causes a 10-second rollover for the EWMA circuitmux code. Previously, this behavior would happen randomly, and result in fluctuating test coverage. Fixes bug 25994; bugfix on 0.3.3.1-alpha. - Use X509_new() to allocate certificates that will be freed later with X509_free(). Previously, some parts of the unit tests had used tor_malloc_zero(), which is incorrect, and which caused test failures on Windows when they were built with extra hardening. Fixes bugs 25943 and 25944; bugfix on 0.2.8.1-alpha. Patch by Marcin Cieślak. - While running the circuit_timeout test, fix the PRNG to a deterministic AES stream, so that the test coverage from this test will itself be deterministic. Fixes bug 25995; bugfix on 0.2.2.2-alpha. o Minor bugfixes (vanguards): - Allow the last hop in a vanguard circuit to be the same as our first, to prevent the adversary from influencing guard node choice by choice of last hop. Also prevent the creation of A - B - A paths, or A - A paths, which are forbidden by relays. Fixes bug 25870; bugfix on 0.3.3.1-alpha. o Code simplification and refactoring: - Remove duplicate code in parse_{c,s}method_line and bootstrap their functionalities into a single function. Fixes bug 6236; bugfix on 0.2.3.6-alpha. - We remove the PortForwsrding and PortForwardingHelper options, related functions, and the port_forwarding tests. These options were used by the now-deprecated Vidalia to help ordinary users become Tor relays or bridges. Closes ticket 25409. Patch by Neel Chauhan. - In order to make the OR and dir checking function in router.c less confusing we renamed some functions and consider_testing_reachability() has been split into router_should_check_reachability() and router_do_reachability_checks(). Also we improved the documentation in some functions. Closes ticket 18918. - Initial work to isolate Libevent usage to a handful of modules in our codebase, to simplify our call structure, and so that we can more easily change event loops in the future if needed. Closes ticket 23750. - Introduce a function to call getsockname() and return tor_addr_t, to save a little complexity throughout the codebase. Closes ticket 18105. - Make hsdir_index in node_t a hsdir_index_t rather than a pointer as hsdir_index is always present. Also, we move hsdir_index_t into or.h. Closes ticket 23094. Patch by Neel Chauhan. - Merge functions used for describing nodes and suppress the functions that do not allocate memory for the output buffer string. NODE_DESC_BUF_LEN constant and format_node_description() function cannot be used externally from router.c module anymore. Closes ticket 25432. Patch by valentecaio. - Our main loop has been simplified so that all important operations happen inside events. Previously, some operations had to happen outside the event loop, to prevent infinite sequences of event activations. Closes ticket 25374. - Put a SHA1 public key digest in hs_service_intro_point_t, and use it in register_intro_circ() and service_intro_point_new(). This prevents the digest from being re-calculated each time. Closes ticket 23107. Patch by Neel Chauhan. - Refactor token-bucket implementations to use a common backend. Closes ticket 25766. - Remove extern declaration of stats_n_seconds_working variable from main, protecting its accesses with get_uptime() and reset_uptime() functions. Closes ticket 25081, patch by “valentecaio”. - Remove our previous logic for "cached gettimeofday()" -- our coarse monotonic timers are fast enough for this purpose, and far less error-prone. Implements part of ticket 25927. - Remove the return value for fascist_firewall_choose_address_base(), and sister functions such as fascist_firewall_choose_address_node() and fascist_firewall_choose_address_rs(). Also, while we're here, initialize the ap argument as leaving it uninitialized can pose a security hazard. Closes ticket 24734. Patch by Neel Chauhan. - Rename two fields of connection_t struct. timestamp_lastwritten is renamed to timestamp_last_write_allowed and timestamp_lastread is renamed to timestamp_last_read_allowed. Closes ticket 24714, patch by "valentecaio". - Since Tor requires C99, remove our old workaround code for libc implementations where free(NULL) doesn't work. Closes ticket 24484. - Use our standard rate-limiting code to deal with excessive libevent failures, rather than the hand-rolled logic we had before. Closes ticket 26016. - We remove the return value of node_get_prim_orport() and node_get_prim_dirport(), and introduce node_get_prim_orport() in node_ipv6_or_preferred() and node_ipv6_dir_preferred() in order to check for a null address. Closes ticket 23873. Patch by Neel Chauhan. - We switch to should_record_bridge_info() in geoip_note_client_seen() and options_need_geoip_info() instead of accessing the configuration values directly. Fixes bug 25290; bugfix on 0.2.1.6-alpha. Patch by Neel Chauhan. o Deprecated features: - As we are not recommending 0.2.5 anymore, we require relays that once had an ed25519 key associated with their RSA key to always have that key, instead of allowing them to drop back to a version that didn't support ed25519. This means they need to use a new RSA key if they want to downgrade to an older version of tor without ed25519. Closes ticket 20522. o Documentation: - Correct an IPv6 error in the documentation for ExitPolicy. Closes ticket 25857. Patch from "CTassisF". o Removed features: - Directory authorities will no longer support voting according to any consensus method before consensus method 25. This keeps authorities compatible with all authorities running 0.2.9.8 and later, and does not break any clients or relays. Implements ticket 24378 and proposal 290. - The PortForwarding and PortForwardingHelper features have been removed. The reasoning is, given that implementations of NAT traversal protocols within common consumer grade routers are frequently buggy, and that the target audience for a NAT punching feature is a perhaps less-technically-inclined relay operator, when the helper fails to setup traversal the problems are usually deep, ugly, and very router specific, making them horrendously impossible for technical support to reliable assist with, and thus resulting in frustration all around. Unfortunately, relay operators who would like to run relays behind NATs will need to become more familiar with the port forwarding configurations on their local router. Closes 25409. - The TestingEnableTbEmptyEvent option has been removed. It was used in testing simulations to measure how often connection buckets were emptied, in order to improve our scheduling, but it has not been actively used in years. Closes ticket 25760. - The old "round-robin" circuit multiplexer (circuitmux) implementation has been removed, along with a fairly large set of code that existed to support it. It has not been the default circuitmux since we introduced the "EWMA" circuitmux in 0.2.4.x, but it still required an unreasonable amount of memory and CPU. Closes ticket 25268. Changes in version 0.3.3.5-rc - 2018-04-15 Tor 0.3.3.5-rc fixes various bugs in earlier versions of Tor, including some that could affect reliability or correctness. This is the first release candidate in the 0.3.3 series. If we find no new bugs or regression here, then the first stable 0.3.3 release will be nearly identical to this one. o Major bugfixes (security, protover, voting): - Revise Rust implementation of protover to use a more memory- efficient voting algorithm and corresponding data structures, thus avoiding a potential memory-based DoS attack where specially crafted protocol strings would expand to fill available memory. Fixes bug 24031; bugfix on 0.3.3.1-alpha. o Major bugfixes (performance, load balancing): - Directory authorities no longer vote in favor of the Guard flag for relays without directory support. Starting in Tor 0.3.0.1-alpha, clients have been avoiding using such relays in the Guard position, leading to increasingly broken load balancing for the 5%-or-so of Guards that don't advertise directory support. Fixes bug 22310; bugfix on 0.3.0.6. o Minor feature (continuous integration): - Update the Travis CI configuration to use the stable Rust channel, now that we have decided to require that. Closes ticket 25714. o Minor features (config options): - Change the way the default value for MaxMemInQueues is calculated. We now use 40% of the hardware RAM if the system has 8 GB RAM or more. Otherwise we use the former value of 75%. Closes ticket 24782. o Minor features (geoip): - Update geoip and geoip6 to the April 3 2018 Maxmind GeoLite2 Country database. Closes ticket 25718. o Minor bugfixes (client): - When using a listed relay as a bridge, and also using microdescriptors, and considering that relay as a non-bridge in a circuit, treat its microdescriptor as a valid source of information about that relay. This change should prevent a non- fatal assertion error. Fixes bug 25691; bugfix on 0.3.3.4-alpha. o Minor bugfixes (controller): - Restore the correct operation of the RESOLVE command, which had been broken since we added the ability to enable/disable DNS on specific listener ports. Fixes bug 25617; bugfix on 0.2.9.3-alpha. o Minor bugfixes (distribution, compilation, rust): - Build correctly when the rust dependencies submodule is loaded, but the TOR_RUST_DEPENDENCIES environment variable is not set. Fixes bug 25679; bugfix on 0.3.3.1-alpha. - Actually include all of our Rust source in our source distributions. (Previously, a few of the files were accidentally omitted.) Fixes bug 25732; bugfix on 0.3.3.2-alpha. o Minor bugfixes (documentation): - Document that the PerConnBW{Rate,Burst} options will fall back to their corresponding consensus parameters only if those parameters are set. Previously we had claimed that these values would always be set in the consensus. Fixes bug 25296; bugfix on 0.2.2.7-alpha. - Revert a misformatting issue in the ExitPolicy documentation. Fixes bug 25582; bugfix on 0.3.3.1-alpha. o Minor bugfixes (exit relay DNS retries): - Re-attempt timed-out DNS queries 3 times before failure, since our timeout is 5 seconds for them, but clients wait 10-15. Also allow slightly more timeouts per resolver when an exit has multiple resolvers configured. Fixes bug 21394; bugfix on 0.3.1.9. o Minor bugfixes (onion services): - Re-instate counting the client HSDir fetch circuits against the MaxClientCircuitsPending rate limit. Fixes bug 24989; bugfix on 0.3.3.1-alpha. - Remove underscores from the _HSLayer{2,3}Nodes options. This expert-user configuration can now be enabled as HSLayer{2,3}Nodes. Fixes bug 25581; bugfix on 0.3.3.1-alpha o Code simplification and refactoring: - Move the list of default directory authorities to its own file. Closes ticket 24854. Patch by "beastr0". o Documentation (manpage, denial of service): - Provide more detail about the denial-of-service options, by listing each mitigation and explaining how they relate. Closes ticket 25248. Changes in version 0.3.3.4-alpha - 2018-03-29 Tor 0.3.3.4-alpha includes various bugfixes for issues found during the alpha testing of earlier releases in its series. We are approaching a stable 0.3.3.4-alpha release: more testing is welcome! o New system requirements: - When built with Rust, Tor now depends on version 0.2.39 of the libc crate. Closes tickets 25310 and 25664. o Major bugfixes (relay, connection): - If we have failed to connect to a relay and received a connection refused, timeout, or similar error (at the TCP level), do not try that same address/port again for 60 seconds after the failure has occurred. Fixes bug 24767; bugfix on 0.0.6. o Minor features (geoip): - Update geoip and geoip6 to the March 8 2018 Maxmind GeoLite2 Country database. Closes ticket 25469. o Minor features (log messages): - Improve log message in the out-of-memory handler to include information about memory usage from the different compression backends. Closes ticket 25372. o Minor features (sandbox): - Explicitly permit the poll() system call when the Linux seccomp2-based sandbox is enabled: apparently, some versions of libc use poll() when calling getpwnam(). Closes ticket 25313. o Minor bugfixes (C correctness): - Fix a very unlikely (impossible, we believe) null pointer dereference. Fixes bug 25629; bugfix on 0.2.9.15. Found by Coverity; this is CID 1430932. o Minor bugfixes (channel, client): - Better identify client connection when reporting to the geoip client cache. Fixes bug 24904; bugfix on 0.3.1.7. o Minor bugfixes (compilation): - Fix a C99 compliance issue in our configuration script that caused compilation issues when compiling Tor with certain versions of xtools. Fixes bug 25474; bugfix on 0.3.2.5-alpha. o Minor bugfixes (controller, reliability): - Avoid a (nonfatal) assertion failure when extending a one-hop circuit from the controller to become a multihop circuit. Fixes bug 24903; bugfix on 0.2.5.2-alpha. o Major bugfixes (networking): - Tor will no longer reject IPv6 address strings from Tor Browser when they are passed as hostnames in SOCKS5 requests. Fixes bug 25036, bugfix on Tor 0.3.1.2. o Minor bugfixes (networking): - string_is_valid_hostname() will not consider IP strings to be valid hostnames. Fixes bug 25055; bugfix on Tor 0.2.5.5. o Minor bugfixes (onion service v3): - Avoid an assertion failure when the next onion service descriptor rotation type is out of sync with the consensus's valid-after time. Instead, log a warning message with extra information, so we can better hunt down the cause of this assertion. Fixes bug 25306; bugfix on 0.3.2.1-alpha. o Minor bugfixes (testing): - Avoid intermittent test failures due to a test that had relied on onion service introduction point creation finishing within 5 seconds of real clock time. Fixes bug 25450; bugfix on 0.3.1.3-alpha. - Rust crates are now automatically detected and tested. Previously, some crates were not tested by `make test-rust` due to a static string in the `src/test/test_rust.sh` script specifying which crates to test. Fixes bug 25560; bugfix on 0.3.3.3-alpha. o Minor bugfixes (testing, benchmarks): - Fix a crash when running benchmark tests on win32 systems. The crash was due to a mutex that wasn't initialized before logging and options were initialized. Fixes bug 25479; bugfix on 0.3.3.3-alpha. o Minor bugfixes (warnings, ipv6): - Avoid a bug warning that could occur when trying to connect to a relay over IPv6. This warning would occur on a Tor instance that downloads router descriptors, but prefers to use microdescriptors. Fixes bug 25213; bugfix on 0.3.3.1-alpha. o Code simplification and refactoring: - Remove the old (deterministic) directory retry logic entirely: We've used exponential backoff exclusively for some time. Closes ticket 23814. o Documentation: - Improved the documentation of AccountingStart parameter. Closes ticket 23635. - Update the documentation for "Log" to include the current list of logging domains. Closes ticket 25378. Changes in version 0.3.1.10 - 2018-03-03 Tor 0.3.1.10 backports a number of bugfixes, including important fixes for security issues. It includes an important security fix for a remote crash attack against directory authorities, tracked as TROVE-2018-001. This release also backports our new system for improved resistance to denial-of-service attacks against relays. This release also fixes several minor bugs and annoyances from earlier releases. All directory authorities should upgrade to one of the versions released today. Relays running 0.3.1.x may wish to update to one of the versions released today, for the DoS mitigations. Please note: according to our release calendar, Tor 0.3.1 will no longer be supported after 1 July 2018. If you will be running Tor after that date, you should make sure to plan to upgrade to the latest stable version, or downgrade to 0.2.9 (which will receive long-term support). o Major bugfixes (denial-of-service, directory authority, backport from 0.3.3.3-alpha): - Fix a protocol-list handling bug that could be used to remotely crash directory authorities with a null-pointer exception. Fixes bug 25074; bugfix on 0.2.9.4-alpha. Also tracked as TROVE-2018-001 and CVE-2018-0490. o Major features (denial-of-service mitigation, backport from 0.3.3.2-alpha): - Give relays some defenses against the recent network overload. We start with three defenses (default parameters in parentheses). First: if a single client address makes too many concurrent connections (>100), hang up on further connections. Second: if a single client address makes circuits too quickly (more than 3 per second, with an allowed burst of 90) while also having too many connections open (3), refuse new create cells for the next while (1-2 hours). Third: if a client asks to establish a rendezvous point to you directly, ignore the request. These defenses can be manually controlled by new torrc options, but relays will also take guidance from consensus parameters, so there's no need to configure anything manually. Implements ticket 24902. o Minor features (linux seccomp2 sandbox, backport from 0.3.2.5-alpha): - Update the sandbox rules so that they should now work correctly with Glibc 2.26. Closes ticket 24315. o Major bugfixes (onion services, retry behavior, backport from 0.3.3.1-alpha): - Fix an "off by 2" error in counting rendezvous failures on the onion service side. While we thought we would stop the rendezvous attempt after one failed circuit, we were actually making three circuit attempts before giving up. Now switch to a default of 2, and allow the consensus parameter "hs_service_max_rdv_failures" to override. Fixes bug 24895; bugfix on 0.0.6. o Major bugfixes (protocol versions, backport from 0.3.3.2-alpha): - Add Link protocol version 5 to the supported protocols list. Fixes bug 25070; bugfix on 0.3.1.1-alpha. o Major bugfixes (relay, backport from 0.3.3.1-alpha): - Fix a set of false positives where relays would consider connections to other relays as being client-only connections (and thus e.g. deserving different link padding schemes) if those relays fell out of the consensus briefly. Now we look only at the initial handshake and whether the connection authenticated as a relay. Fixes bug 24898; bugfix on 0.3.1.1-alpha. o Minor features (denial-of-service avoidance, backport from 0.3.3.2-alpha): - Make our OOM handler aware of the geoip client history cache so it doesn't fill up the memory. This check is important for IPv6 and our DoS mitigation subsystem. Closes ticket 25122. o Minor feature (relay statistics, backport from 0.3.2.6-alpha): - Change relay bandwidth reporting stats interval from 4 hours to 24 hours in order to reduce the efficiency of guard discovery attacks. Fixes ticket 23856. o Minor features (compatibility, OpenSSL, backport from 0.3.3.3-alpha): - Tor will now support TLS1.3 once OpenSSL 1.1.1 is released. Previous versions of Tor would not have worked with OpenSSL 1.1.1, since they neither disabled TLS 1.3 nor enabled any of the ciphersuites it requires. Now we enable the TLS 1.3 ciphersuites. Closes ticket 24978. o Minor features (fallback directory mirrors, backport from 0.3.2.9): - The fallback directory list has been re-generated based on the current status of the network. Tor uses fallback directories to bootstrap when it doesn't yet have up-to-date directory information. Closes ticket 24801. - Make the default DirAuthorityFallbackRate 0.1, so that clients prefer to bootstrap from fallback directory mirrors. This is a follow-up to 24679, which removed weights from the default fallbacks. Implements ticket 24681. o Minor features (geoip): - Update geoip and geoip6 to the February 7 2018 Maxmind GeoLite2 Country database. o Minor bugfix (channel connection, backport from 0.3.3.2-alpha): - Use the actual observed address of an incoming relay connection, not the canonical address of the relay from its descriptor, when making decisions about how to handle the incoming connection. Fixes bug 24952; bugfix on 0.2.4.11-alpha. Patch by "ffmancera". o Minor bugfix (directory authority, backport from 0.3.3.2-alpha): - Directory authorities, when refusing a descriptor from a rejected relay, now explicitly tell the relay (in its logs) to set a valid ContactInfo address and contact the bad-relays@ mailing list. Fixes bug 25170; bugfix on 0.2.9.1. o Minor bugfixes (address selection, backport from 0.3.2.9): - When the fascist_firewall_choose_address_ functions don't find a reachable address, set the returned address to the null address and port. This is a precautionary measure, because some callers do not check the return value. Fixes bug 24736; bugfix on 0.2.8.2-alpha. o Major bugfixes (bootstrapping, backport from 0.3.2.5-alpha): - Fetch descriptors aggressively whenever we lack enough to build circuits, regardless of how many descriptors we are missing. Previously, we would delay launching the fetch when we had fewer than 15 missing descriptors, even if some of those descriptors were blocking circuits from building. Fixes bug 23985; bugfix on 0.1.1.11-alpha. The effects of this bug became worse in 0.3.0.3-alpha, when we began treating missing descriptors from our primary guards as a reason to delay circuits. - Don't try fetching microdescriptors from relays that have failed to deliver them in the past. Fixes bug 23817; bugfix on 0.3.0.1-alpha. o Minor bugfixes (compilation, backport from 0.3.2.7-rc): - Fix a signed/unsigned comparison warning introduced by our fix to TROVE-2017-009. Fixes bug 24480; bugfix on 0.2.5.16. o Minor bugfixes (control port, linux seccomp2 sandbox, backport from 0.3.2.5-alpha): - Avoid a crash when attempting to use the seccomp2 sandbox together with the OwningControllerProcess feature. Fixes bug 24198; bugfix on 0.2.5.1-alpha. o Minor bugfixes (denial-of-service, backport from 0.3.3.3-alpha): - Fix a possible crash on malformed consensus. If a consensus had contained an unparseable protocol line, it could have made clients and relays crash with a null-pointer exception. To exploit this issue, however, an attacker would need to be able to subvert the directory authority system. Fixes bug 25251; bugfix on 0.2.9.4-alpha. Also tracked as TROVE-2018-004. o Minor bugfixes (directory cache, backport from 0.3.2.5-alpha): - Recover better from empty or corrupt files in the consensus cache directory. Fixes bug 24099; bugfix on 0.3.1.1-alpha. - When a consensus diff calculation is only partially successful, only record the successful parts as having succeeded. Partial success can happen if (for example) one compression method fails but the others succeed. Previously we misrecorded all the calculations as having succeeded, which would later cause a nonfatal assertion failure. Fixes bug 24086; bugfix on 0.3.1.1-alpha. o Minor bugfixes (entry guards, backport from 0.3.2.3-alpha): - Tor now updates its guard state when it reads a consensus regardless of whether it's missing descriptors. That makes tor use its primary guards to fetch descriptors in some edge cases where it would previously have used fallback directories. Fixes bug 23862; bugfix on 0.3.0.1-alpha. o Minor bugfixes (logging, backport from 0.3.3.2-alpha): - Don't treat inability to store a cached consensus object as a bug: it can happen normally when we are out of disk space. Fixes bug 24859; bugfix on 0.3.1.1-alpha. o Minor bugfixes (memory usage, backport from 0.3.2.8-rc): - When queuing DESTROY cells on a channel, only queue the circuit-id and reason fields: not the entire 514-byte cell. This fix should help mitigate any bugs or attacks that fill up these queues, and free more RAM for other uses. Fixes bug 24666; bugfix on 0.2.5.1-alpha. o Minor bugfixes (network layer, backport from 0.3.2.5-alpha): - When closing a connection via close_connection_immediately(), we mark it as "not blocked on bandwidth", to prevent later calls from trying to unblock it, and give it permission to read. This fixes a backtrace warning that can happen on relays under various circumstances. Fixes bug 24167; bugfix on 0.1.0.1-rc. o Minor bugfixes (path selection, backport from 0.3.2.4-alpha): - When selecting relays by bandwidth, avoid a rounding error that could sometimes cause load to be imbalanced incorrectly. Previously, we would always round upwards; now, we round towards the nearest integer. This had the biggest effect when a relay's weight adjustments should have given it weight 0, but it got weight 1 instead. Fixes bug 23318; bugfix on 0.2.4.3-alpha. - When calculating the fraction of nodes that have descriptors, and all nodes in the network have zero bandwidths, count the number of nodes instead. Fixes bug 23318; bugfix on 0.2.4.10-alpha. - Actually log the total bandwidth in compute_weighted_bandwidths(). Fixes bug 24170; bugfix on 0.2.4.3-alpha. o Minor bugfixes (performance, fragile-hardening, backport from 0.3.3.1-alpha): - Improve the performance of our consensus-diff application code when Tor is built with the --enable-fragile-hardening option set. Fixes bug 24826; bugfix on 0.3.1.1-alpha. o Minor bugfixes (OSX, backport from 0.3.3.1-alpha): - Don't exit the Tor process if setrlimit() fails to change the file limit (which can happen sometimes on some versions of OSX). Fixes bug 21074; bugfix on 0.0.9pre5. o Minor bugfixes (portability, msvc, backport from 0.3.2.9): - Fix a bug in the bit-counting parts of our timing-wheel code on MSVC. (Note that MSVC is still not a supported build platform, due to cyptographic timing channel risks.) Fixes bug 24633; bugfix on 0.2.9.1-alpha. o Minor bugfixes (relay, partial backport): - Make the internal channel_is_client() function look at what sort of connection handshake the other side used, rather than whether the other side ever sent a create_fast cell to us. Backports part of the fixes from bugs 22805 and 24898. o Minor bugfixes (spec conformance, backport from 0.3.3.3-alpha): - Forbid "-0" as a protocol version. Fixes part of bug 25249; bugfix on 0.2.9.4-alpha. - Forbid UINT32_MAX as a protocol version. Fixes part of bug 25249; bugfix on 0.2.9.4-alpha. o Code simplification and refactoring (backport from 0.3.3.3-alpha): - Update the "rust dependencies" submodule to be a project-level repository, rather than a user repository. Closes ticket 25323. Changes in version 0.2.9.15 - 2018-03-03 Tor 0.2.9.15 backports important security and stability bugfixes from later Tor releases. It includes an important security fix for a remote crash attack against directory authorities, tracked as TROVE-2018-001. This release also backports our new system for improved resistance to denial-of-service attacks against relays. This release also fixes several minor bugs and annoyances from earlier releases. All directory authorities should upgrade to one of the versions released today. Relays running 0.2.9.x may wish to update to one of the versions released today, for the DoS mitigations. o Major bugfixes (denial-of-service, directory authority, backport from 0.3.3.3-alpha): - Fix a protocol-list handling bug that could be used to remotely crash directory authorities with a null-pointer exception. Fixes bug 25074; bugfix on 0.2.9.4-alpha. Also tracked as TROVE-2018-001 and CVE-2018-0490. o Major features (denial-of-service mitigation): - Give relays some defenses against the recent network overload. We start with three defenses (default parameters in parentheses). First: if a single client address makes too many concurrent connections (>100), hang up on further connections. Second: if a single client address makes circuits too quickly (more than 3 per second, with an allowed burst of 90) while also having too many connections open (3), refuse new create cells for the next while (1-2 hours). Third: if a client asks to establish a rendezvous point to you directly, ignore the request. These defenses can be manually controlled by new torrc options, but relays will also take guidance from consensus parameters, so there's no need to configure anything manually. Implements ticket 24902. o Major bugfixes (bootstrapping): - Fetch descriptors aggressively whenever we lack enough to build circuits, regardless of how many descriptors we are missing. Previously, we would delay launching the fetch when we had fewer than 15 missing descriptors, even if some of those descriptors were blocking circuits from building. Fixes bug 23985; bugfix on 0.1.1.11-alpha. The effects of this bug became worse in 0.3.0.3-alpha, when we began treating missing descriptors from our primary guards as a reason to delay circuits. o Major bugfixes (onion services, retry behavior): - Fix an "off by 2" error in counting rendezvous failures on the onion service side. While we thought we would stop the rendezvous attempt after one failed circuit, we were actually making three circuit attempts before giving up. Now switch to a default of 2, and allow the consensus parameter "hs_service_max_rdv_failures" to override. Fixes bug 24895; bugfix on 0.0.6. o Minor feature (relay statistics): - Change relay bandwidth reporting stats interval from 4 hours to 24 hours in order to reduce the efficiency of guard discovery attacks. Fixes ticket 23856. o Minor features (compatibility, OpenSSL): - Tor will now support TLS1.3 once OpenSSL 1.1.1 is released. Previous versions of Tor would not have worked with OpenSSL 1.1.1, since they neither disabled TLS 1.3 nor enabled any of the ciphersuites it requires. Now we enable the TLS 1.3 ciphersuites. Closes ticket 24978. o Minor features (denial-of-service avoidance): - Make our OOM handler aware of the geoip client history cache so it doesn't fill up the memory. This check is important for IPv6 and our DoS mitigation subsystem. Closes ticket 25122. o Minor features (fallback directory mirrors): - The fallback directory list has been re-generated based on the current status of the network. Tor uses fallback directories to bootstrap when it doesn't yet have up-to-date directory information. Closes ticket 24801. - Make the default DirAuthorityFallbackRate 0.1, so that clients prefer to bootstrap from fallback directory mirrors. This is a follow-up to 24679, which removed weights from the default fallbacks. Implements ticket 24681. o Minor features (geoip): - Update geoip and geoip6 to the February 7 2018 Maxmind GeoLite2 Country database. o Minor features (linux seccomp2 sandbox): - Update the sandbox rules so that they should now work correctly with Glibc 2.26. Closes ticket 24315. o Minor bugfix (channel connection): - Use the actual observed address of an incoming relay connection, not the canonical address of the relay from its descriptor, when making decisions about how to handle the incoming connection. Fixes bug 24952; bugfix on 0.2.4.11-alpha. Patch by "ffmancera". o Minor bugfix (directory authority): - Directory authorities, when refusing a descriptor from a rejected relay, now explicitly tell the relay (in its logs) to set a valid ContactInfo address and contact the bad-relays@ mailing list. Fixes bug 25170; bugfix on 0.2.9.1. o Minor bugfixes (address selection): - When the fascist_firewall_choose_address_ functions don't find a reachable address, set the returned address to the null address and port. This is a precautionary measure, because some callers do not check the return value. Fixes bug 24736; bugfix on 0.2.8.2-alpha. o Minor bugfixes (compilation): - Fix a signed/unsigned comparison warning introduced by our fix to TROVE-2017-009. Fixes bug 24480; bugfix on 0.2.5.16. o Minor bugfixes (control port, linux seccomp2 sandbox): - Avoid a crash when attempting to use the seccomp2 sandbox together with the OwningControllerProcess feature. Fixes bug 24198; bugfix on 0.2.5.1-alpha. o Minor bugfixes (denial-of-service, backport from 0.3.3.3-alpha): - Fix a possible crash on malformed consensus. If a consensus had contained an unparseable protocol line, it could have made clients and relays crash with a null-pointer exception. To exploit this issue, however, an attacker would need to be able to subvert the directory authority system. Fixes bug 25251; bugfix on 0.2.9.4-alpha. Also tracked as TROVE-2018-004. o Minor bugfixes (memory usage): - When queuing DESTROY cells on a channel, only queue the circuit-id and reason fields: not the entire 514-byte cell. This fix should help mitigate any bugs or attacks that fill up these queues, and free more RAM for other uses. Fixes bug 24666; bugfix on 0.2.5.1-alpha. o Minor bugfixes (network layer): - When closing a connection via close_connection_immediately(), we mark it as "not blocked on bandwidth", to prevent later calls from trying to unblock it, and give it permission to read. This fixes a backtrace warning that can happen on relays under various circumstances. Fixes bug 24167; bugfix on 0.1.0.1-rc. o Minor bugfixes (OSX): - Don't exit the Tor process if setrlimit() fails to change the file limit (which can happen sometimes on some versions of OSX). Fixes bug 21074; bugfix on 0.0.9pre5. o Minor bugfixes (path selection): - When selecting relays by bandwidth, avoid a rounding error that could sometimes cause load to be imbalanced incorrectly. Previously, we would always round upwards; now, we round towards the nearest integer. This had the biggest effect when a relay's weight adjustments should have given it weight 0, but it got weight 1 instead. Fixes bug 23318; bugfix on 0.2.4.3-alpha. - When calculating the fraction of nodes that have descriptors, and all nodes in the network have zero bandwidths, count the number of nodes instead. Fixes bug 23318; bugfix on 0.2.4.10-alpha. - Actually log the total bandwidth in compute_weighted_bandwidths(). Fixes bug 24170; bugfix on 0.2.4.3-alpha. o Minor bugfixes (portability, msvc): - Fix a bug in the bit-counting parts of our timing-wheel code on MSVC. (Note that MSVC is still not a supported build platform, due to cryptographic timing channel risks.) Fixes bug 24633; bugfix on 0.2.9.1-alpha. o Minor bugfixes (relay): - Make the internal channel_is_client() function look at what sort of connection handshake the other side used, rather than whether the other side ever sent a create_fast cell to us. Backports part of the fixes from bugs 22805 and 24898. o Minor bugfixes (spec conformance, backport from 0.3.3.3-alpha): - Forbid "-0" as a protocol version. Fixes part of bug 25249; bugfix on 0.2.9.4-alpha. - Forbid UINT32_MAX as a protocol version. Fixes part of bug 25249; bugfix on 0.2.9.4-alpha. Changes in version 0.3.2.10 - 2018-03-03 Tor 0.3.2.10 is the second stable release in the 0.3.2 series. It backports a number of bugfixes, including important fixes for security issues. It includes an important security fix for a remote crash attack against directory authorities, tracked as TROVE-2018-001. Additionally, it backports a fix for a bug whose severity we have upgraded: Bug 24700, which was fixed in 0.3.3.2-alpha, can be remotely triggered in order to crash relays with a use-after-free pattern. As such, we are now tracking that bug as TROVE-2018-002 and CVE-2018-0491, and backporting it to earlier releases. This bug affected versions 0.3.2.1-alpha through 0.3.2.9, as well as version 0.3.3.1-alpha. This release also backports our new system for improved resistance to denial-of-service attacks against relays. This release also fixes several minor bugs and annoyances from earlier releases. Relays running 0.3.2.x SHOULD upgrade to one of the versions released today, for the fix to TROVE-2018-002. Directory authorities should also upgrade. (Relays on earlier versions might want to update too for the DoS mitigations.) o Major bugfixes (denial-of-service, directory authority, backport from 0.3.3.3-alpha): - Fix a protocol-list handling bug that could be used to remotely crash directory authorities with a null-pointer exception. Fixes bug 25074; bugfix on 0.2.9.4-alpha. Also tracked as TROVE-2018-001 and CVE-2018-0490. o Major bugfixes (scheduler, KIST, denial-of-service, backport from 0.3.3.2-alpha): - Avoid adding the same channel twice in the KIST scheduler pending list, which could lead to remote denial-of-service use-after-free attacks against relays. Fixes bug 24700; bugfix on 0.3.2.1-alpha. o Major features (denial-of-service mitigation, backport from 0.3.3.2-alpha): - Give relays some defenses against the recent network overload. We start with three defenses (default parameters in parentheses). First: if a single client address makes too many concurrent connections (>100), hang up on further connections. Second: if a single client address makes circuits too quickly (more than 3 per second, with an allowed burst of 90) while also having too many connections open (3), refuse new create cells for the next while (1-2 hours). Third: if a client asks to establish a rendezvous point to you directly, ignore the request. These defenses can be manually controlled by new torrc options, but relays will also take guidance from consensus parameters, so there's no need to configure anything manually. Implements ticket 24902. o Major bugfixes (onion services, retry behavior, backport from 0.3.3.1-alpha): - Fix an "off by 2" error in counting rendezvous failures on the onion service side. While we thought we would stop the rendezvous attempt after one failed circuit, we were actually making three circuit attempts before giving up. Now switch to a default of 2, and allow the consensus parameter "hs_service_max_rdv_failures" to override. Fixes bug 24895; bugfix on 0.0.6. - New-style (v3) onion services now obey the "max rendezvous circuit attempts" logic. Previously they would make as many rendezvous circuit attempts as they could fit in the MAX_REND_TIMEOUT second window before giving up. Fixes bug 24894; bugfix on 0.3.2.1-alpha. o Major bugfixes (protocol versions, backport from 0.3.3.2-alpha): - Add Link protocol version 5 to the supported protocols list. Fixes bug 25070; bugfix on 0.3.1.1-alpha. o Major bugfixes (relay, backport from 0.3.3.1-alpha): - Fix a set of false positives where relays would consider connections to other relays as being client-only connections (and thus e.g. deserving different link padding schemes) if those relays fell out of the consensus briefly. Now we look only at the initial handshake and whether the connection authenticated as a relay. Fixes bug 24898; bugfix on 0.3.1.1-alpha. o Major bugfixes (scheduler, consensus, backport from 0.3.3.2-alpha): - The scheduler subsystem was failing to promptly notice changes in consensus parameters, making it harder to switch schedulers network-wide. Fixes bug 24975; bugfix on 0.3.2.1-alpha. o Minor features (denial-of-service avoidance, backport from 0.3.3.2-alpha): - Make our OOM handler aware of the geoip client history cache so it doesn't fill up the memory. This check is important for IPv6 and our DoS mitigation subsystem. Closes ticket 25122. o Minor features (compatibility, OpenSSL, backport from 0.3.3.3-alpha): - Tor will now support TLS1.3 once OpenSSL 1.1.1 is released. Previous versions of Tor would not have worked with OpenSSL 1.1.1, since they neither disabled TLS 1.3 nor enabled any of the ciphersuites it requires. Now we enable the TLS 1.3 ciphersuites. Closes ticket 24978. o Minor features (geoip): - Update geoip and geoip6 to the February 7 2018 Maxmind GeoLite2 Country database. o Minor features (logging, diagnostic, backport from 0.3.3.2-alpha): - When logging a failure to create an onion service's descriptor, also log what the problem with the descriptor was. Diagnostic for ticket 24972. o Minor bugfix (channel connection, backport from 0.3.3.2-alpha): - Use the actual observed address of an incoming relay connection, not the canonical address of the relay from its descriptor, when making decisions about how to handle the incoming connection. Fixes bug 24952; bugfix on 0.2.4.11-alpha. Patch by "ffmancera". o Minor bugfixes (denial-of-service, backport from 0.3.3.3-alpha): - Fix a possible crash on malformed consensus. If a consensus had contained an unparseable protocol line, it could have made clients and relays crash with a null-pointer exception. To exploit this issue, however, an attacker would need to be able to subvert the directory authority system. Fixes bug 25251; bugfix on 0.2.9.4-alpha. Also tracked as TROVE-2018-004. o Minor bugfix (directory authority, backport from 0.3.3.2-alpha): - Directory authorities, when refusing a descriptor from a rejected relay, now explicitly tell the relay (in its logs) to set a valid ContactInfo address and contact the bad-relays@ mailing list. Fixes bug 25170; bugfix on 0.2.9.1. o Minor bugfixes (build, rust, backport from 0.3.3.1-alpha): - When building with Rust on OSX, link against libresolv, to work around the issue at https://github.com/rust-lang/rust/issues/46797. Fixes bug 24652; bugfix on 0.3.1.1-alpha. o Minor bugfixes (onion services, backport from 0.3.3.2-alpha): - Remove a BUG() statement when a client fetches an onion descriptor that has a lower revision counter than the one in its cache. This can happen in normal circumstances due to HSDir desync. Fixes bug 24976; bugfix on 0.3.2.1-alpha. o Minor bugfixes (logging, backport from 0.3.3.2-alpha): - Don't treat inability to store a cached consensus object as a bug: it can happen normally when we are out of disk space. Fixes bug 24859; bugfix on 0.3.1.1-alpha. o Minor bugfixes (performance, fragile-hardening, backport from 0.3.3.1-alpha): - Improve the performance of our consensus-diff application code when Tor is built with the --enable-fragile-hardening option set. Fixes bug 24826; bugfix on 0.3.1.1-alpha. o Minor bugfixes (OSX, backport from 0.3.3.1-alpha): - Don't exit the Tor process if setrlimit() fails to change the file limit (which can happen sometimes on some versions of OSX). Fixes bug 21074; bugfix on 0.0.9pre5. o Minor bugfixes (spec conformance, backport from 0.3.3.3-alpha): - Forbid "-0" as a protocol version. Fixes part of bug 25249; bugfix on 0.2.9.4-alpha. - Forbid UINT32_MAX as a protocol version. Fixes part of bug 25249; bugfix on 0.2.9.4-alpha. o Minor bugfixes (testing, backport from 0.3.3.1-alpha): - Fix a memory leak in the scheduler/loop_kist unit test. Fixes bug 25005; bugfix on 0.3.2.7-rc. o Minor bugfixes (v3 onion services, backport from 0.3.3.2-alpha): - Look at the "HSRend" protocol version, not the "HSDir" protocol version, when deciding whether a consensus entry can support the v3 onion service protocol as a rendezvous point. Fixes bug 25105; bugfix on 0.3.2.1-alpha. o Code simplification and refactoring (backport from 0.3.3.3-alpha): - Update the "rust dependencies" submodule to be a project-level repository, rather than a user repository. Closes ticket 25323. o Documentation (backport from 0.3.3.1-alpha) - Document that operators who run more than one relay or bridge are expected to set MyFamily and ContactInfo correctly. Closes ticket 24526. Changes in version 0.3.3.3-alpha - 2018-03-03 Tor 0.3.3.3-alpha is the third alpha release for the 0.3.3.x series. It includes an important security fix for a remote crash attack against directory authorities tracked as TROVE-2018-001. Additionally, with this release, we are upgrading the severity of a bug fixed in 0.3.3.2-alpha. Bug 24700, which was fixed in 0.3.3.2-alpha, can be remotely triggered in order to crash relays with a use-after-free pattern. As such, we are now tracking that bug as TROVE-2018-002 and CVE-2018-0491. This bug affected versions 0.3.2.1-alpha through 0.3.2.9, as well as 0.3.3.1-alpha. This release also fixes several minor bugs and annoyances from earlier releases. Relays running 0.3.2.x should upgrade to one of the versions released today, for the fix to TROVE-2018-002. Directory authorities should also upgrade. (Relays on earlier versions might want to update too for the DoS mitigations.) o Major bugfixes (denial-of-service, directory authority): - Fix a protocol-list handling bug that could be used to remotely crash directory authorities with a null-pointer exception. Fixes bug 25074; bugfix on 0.2.9.4-alpha. Also tracked as TROVE-2018-001 and CVE-2018-0490. o Minor features (compatibility, OpenSSL): - Tor will now support TLS1.3 once OpenSSL 1.1.1 is released. Previous versions of Tor would not have worked with OpenSSL 1.1.1, since they neither disabled TLS 1.3 nor enabled any of the ciphersuites it requires. Now we enable the TLS 1.3 ciphersuites. Closes ticket 24978. o Minor features (logging): - Clarify the log messages produced when getrandom() or a related entropy-generation mechanism gives an error. Closes ticket 25120. o Minor features (testing): - Add a "make test-rust" target to run the rust tests only. Closes ticket 25071. o Minor bugfixes (denial-of-service): - Fix a possible crash on malformed consensus. If a consensus had contained an unparseable protocol line, it could have made clients and relays crash with a null-pointer exception. To exploit this issue, however, an attacker would need to be able to subvert the directory authority system. Fixes bug 25251; bugfix on 0.2.9.4-alpha. Also tracked as TROVE-2018-004. o Minor bugfixes (DoS mitigation): - Add extra safety checks when refilling the circuit creation bucket to ensure we never set a value above the allowed maximum burst. Fixes bug 25202; bugfix on 0.3.3.2-alpha. - When a new consensus arrives, don't update our DoS-mitigation parameters if we aren't a public relay. Fixes bug 25223; bugfix on 0.3.3.2-alpha. o Minor bugfixes (man page, SocksPort): - Remove dead code from the old "SocksSocket" option, and rename SocksSocketsGroupWritable to UnixSocksGroupWritable. The old option still works, but is deprecated. Fixes bug 24343; bugfix on 0.2.6.3. o Minor bugfixes (performance): - Reduce the number of circuits that will be opened at once during the circuit build timeout phase. This is done by increasing the idle timeout to 3 minutes, and lowering the maximum number of concurrent learning circuits to 10. Fixes bug 24769; bugfix on 0.3.1.1-alpha. o Minor bugfixes (spec conformance): - Forbid "-0" as a protocol version. Fixes part of bug 25249; bugfix on 0.2.9.4-alpha. - Forbid UINT32_MAX as a protocol version. Fixes part of bug 25249; bugfix on 0.2.9.4-alpha. o Minor bugfixes (spec conformance, rust): - Resolve a denial-of-service issue caused by an infinite loop in the rust protover code. Fixes bug 25250, bugfix on 0.3.3.1-alpha. Also tracked as TROVE-2018-003. o Code simplification and refactoring: - Update the "rust dependencies" submodule to be a project-level repository, rather than a user repository. Closes ticket 25323. Changes in version 0.3.3.2-alpha - 2018-02-10 Tor 0.3.3.2-alpha is the second alpha in the 0.3.3.x series. It introduces a mechanism to handle the high loads that many relay operators have been reporting recently. It also fixes several bugs in older releases. If this new code proves reliable, we plan to backport it to older supported release series. o Major features (denial-of-service mitigation): - Give relays some defenses against the recent network overload. We start with three defenses (default parameters in parentheses). First: if a single client address makes too many concurrent connections (>100), hang up on further connections. Second: if a single client address makes circuits too quickly (more than 3 per second, with an allowed burst of 90) while also having too many connections open (3), refuse new create cells for the next while (1-2 hours). Third: if a client asks to establish a rendezvous point to you directly, ignore the request. These defenses can be manually controlled by new torrc options, but relays will also take guidance from consensus parameters, so there's no need to configure anything manually. Implements ticket 24902. o Major bugfixes (netflow padding): - Stop adding unneeded channel padding right after we finish flushing to a connection that has been trying to flush for many seconds. Instead, treat all partial or complete flushes as activity on the channel, which will defer the time until we need to add padding. This fix should resolve confusing and scary log messages like "Channel padding timeout scheduled 221453ms in the past." Fixes bug 22212; bugfix on 0.3.1.1-alpha. o Major bugfixes (protocol versions): - Add Link protocol version 5 to the supported protocols list. Fixes bug 25070; bugfix on 0.3.1.1-alpha. o Major bugfixes (scheduler, consensus): - The scheduler subsystem was failing to promptly notice changes in consensus parameters, making it harder to switch schedulers network-wide. Fixes bug 24975; bugfix on 0.3.2.1-alpha. o Minor features (denial-of-service avoidance): - Make our OOM handler aware of the geoip client history cache so it doesn't fill up the memory. This check is important for IPv6 and our DoS mitigation subsystem. Closes ticket 25122. o Minor features (directory authority): - When directory authorities are unable to add signatures to a pending consensus, log the reason why. Closes ticket 24849. o Minor features (geoip): - Update geoip and geoip6 to the February 7 2018 Maxmind GeoLite2 Country database. o Minor features (logging, diagnostic): - When logging a failure to create an onion service's descriptor, also log what the problem with the descriptor was. Diagnostic for ticket 24972. o Minor bugfix (channel connection): - Use the actual observed address of an incoming relay connection, not the canonical address of the relay from its descriptor, when making decisions about how to handle the incoming connection. Fixes bug 24952; bugfix on 0.2.4.11-alpha. Patch by "ffmancera". o Minor bugfix (directory authority): - Directory authorities, when refusing a descriptor from a rejected relay, now explicitly tell the relay (in its logs) to set a valid ContactInfo address and contact the bad-relays@ mailing list. Fixes bug 25170; bugfix on 0.2.9.1. o Minor bugfixes (all versions of Tor): - Use the "misspell" tool to detect and fix typos throughout the source code. Fixes bug 23650; bugfix on various versions of Tor. Patch from Deepesh Pathak. o Minor bugfixes (circuit, cannibalization): - Don't cannibalize preemptively-built circuits if we no longer recognize their first hop. This situation can happen if our Guard relay went off the consensus after the circuit was created. Fixes bug 24469; bugfix on 0.0.6. o Minor bugfixes (correctness): - Remove a nonworking, unnecessary check to see whether a circuit hop's identity digest was set when the circuit failed. Fixes bug 24927; bugfix on 0.2.4.4-alpha. o Minor bugfixes (logging): - Don't treat inability to store a cached consensus object as a bug: it can happen normally when we are out of disk space. Fixes bug 24859; bugfix on 0.3.1.1-alpha. - Fix a (mostly harmless) race condition when invoking LOG_PROTOCOL_WARN message from a subthread while the torrc options are changing. Fixes bug 23954; bugfix on 0.1.1.9-alpha. o Minor bugfixes (onion services): - Remove a BUG() statement when a client fetches an onion descriptor that has a lower revision counter than the one in its cache. This can happen in normal circumstances due to HSDir desync. Fixes bug 24976; bugfix on 0.3.2.1-alpha. - If we are configured to offer a single onion service, don't log long-term established one hop rendezvous points in the heartbeat. Fixes bug 25116; bugfix on 0.2.9.6-rc. o Minor bugfixes (performance): - Avoid calling protocol_list_supports_protocol() from inside tight loops when running with cached routerinfo_t objects. Instead, summarize the relevant protocols as flags in the routerinfo_t, as we do for routerstatus_t objects. This change simplifies our code a little, and saves a large amount of short-term memory allocation operations. Fixes bug 25008; bugfix on 0.2.9.4-alpha. o Minor bugfixes (Rust FFI): - Fix a minor memory leak which would happen whenever the C code would call the Rust implementation of protover_get_supported_protocols(). This was due to the C version returning a static string, whereas the Rust version newly allocated a CString to pass across the FFI boundary. Consequently, the C code was not expecting to need to free() what it was given. Fixes bug 25127; bugfix on 0.3.2.1-alpha. o Minor bugfixes (scheduler, KIST): - Avoid adding the same channel twice in the KIST scheduler pending list, which would waste CPU cycles. Fixes bug 24700; bugfix on 0.3.2.1-alpha. o Minor bugfixes (unit test, monotonic time): - Increase a constant (1msec to 10msec) in the monotonic time test that makes sure the nsec/usec/msec times read are synchronized. This change was needed to accommodate slow systems like armel or when the clock_gettime() is not a VDSO on the running kernel. Fixes bug 25113; bugfix on 0.2.9.1. o Minor bugfixes (v3 onion services): - Look at the "HSRend" protocol version, not the "HSDir" protocol version, when deciding whether a consensus entry can support the v3 onion service protocol as a rendezvous point. Fixes bug 25105; bugfix on 0.3.2.1-alpha. o Code simplification and refactoring: - Remove the unused nodelist_recompute_all_hsdir_indices(). Closes ticket 25108. - Remove a series of counters used to track circuit extend attempts and connection status but that in reality we aren't using for anything other than stats logged by a SIGUSR1 signal. Closes ticket 25163. o Documentation (man page): - The HiddenServiceVersion torrc option accepts only one number: either version 2 or 3. Closes ticket 25026; bugfix on 0.3.2.2-alpha. Changes in version 0.3.3.1-alpha - 2018-01-25 Tor 0.3.3.1-alpha is the first release in the 0.3.3.x series. It adds several new features to Tor, including several improvements to bootstrapping, and support for an experimental "vanguards" feature to resist guard discovery attacks. This series also includes better support for applications that need to embed Tor or manage v3 onion services. o Major features (embedding): - There is now a documented stable API for programs that need to embed Tor. See tor_api.h for full documentation and known bugs. Closes ticket 23684. - Tor now has support for restarting in the same process. Controllers that run Tor using the "tor_api.h" interface can now restart Tor after Tor has exited. This support is incomplete, however: we fixed crash bugs that prevented it from working at all, but many bugs probably remain, including a possibility of security issues. Implements ticket 24581. o Major features (IPv6, directory documents): - Add consensus method 27, which adds IPv6 ORPorts to the microdesc consensus. This information makes it easier for IPv6 clients to bootstrap and choose reachable entry guards. Implements ticket 23826. - Add consensus method 28, which removes IPv6 ORPorts from microdescriptors. Now that the consensus contains IPv6 ORPorts, they are redundant in microdescs. This change will be used by Tor clients on 0.2.8.x and later. (That is to say, with all Tor clients that have IPv6 bootstrap and guard support.) Implements ticket 23828. - Expand the documentation for AuthDirHasIPv6Connectivity when it is set by different numbers of authorities. Fixes 23870 on 0.2.4.1-alpha. o Major features (onion service v3, control port): - The control port now supports commands and events for v3 onion services. It is now possible to create ephemeral v3 services using ADD_ONION. Additionally, several events (HS_DESC, HS_DESC_CONTENT, CIRC and CIRC_MINOR) and commands (GETINFO, HSPOST, ADD_ONION and DEL_ONION) have been extended to support v3 onion services. Closes ticket 20699; implements proposal 284. o Major features (onion services): - Provide torrc options to pin the second and third hops of onion service circuits to a list of nodes. The option HSLayer2Guards pins the second hop, and the option HSLayer3Guards pins the third hop. These options are for use in conjunction with experiments with "vanguards" for preventing guard enumeration attacks. Closes ticket 13837. o Major features (rust, portability, experimental): - Tor now ships with an optional implementation of one of its smaller modules (protover.c) in the Rust programming language. To try it out, install a Rust build environment, and configure Tor with "--enable-rust --enable-cargo-online-mode". This should not cause any user-visible changes, but should help us gain more experience with Rust, and plan future Rust integration work. Implementation by Chelsea Komlo. Closes ticket 22840. o Minor features (storage, configuration): - Users can store cached directory documents somewhere other than the DataDirectory by using the CacheDirectory option. Similarly, the storage location for relay's keys can be overridden with the KeyDirectory option. Closes ticket 22703. o Major features (v3 onion services, ipv6): - When v3 onion service clients send introduce cells, they now include the IPv6 address of the rendezvous point, if it has one. Current v3 onion services running 0.3.2 ignore IPv6 addresses, but in future Tor versions, IPv6-only v3 single onion services will be able to use IPv6 addresses to connect directly to the rendezvous point. Closes ticket 23577. Patch by Neel Chauhan. o Major bugfixes (onion services, retry behavior): - Fix an "off by 2" error in counting rendezvous failures on the onion service side. While we thought we would stop the rendezvous attempt after one failed circuit, we were actually making three circuit attempts before giving up. Now switch to a default of 2, and allow the consensus parameter "hs_service_max_rdv_failures" to override. Fixes bug 24895; bugfix on 0.0.6. - New-style (v3) onion services now obey the "max rendezvous circuit attempts" logic. Previously they would make as many rendezvous circuit attempts as they could fit in the MAX_REND_TIMEOUT second window before giving up. Fixes bug 24894; bugfix on 0.3.2.1-alpha. o Major bugfixes (relays): - Fix a set of false positives where relays would consider connections to other relays as being client-only connections (and thus e.g. deserving different link padding schemes) if those relays fell out of the consensus briefly. Now we look only at the initial handshake and whether the connection authenticated as a relay. Fixes bug 24898; bugfix on 0.3.1.1-alpha. o Minor feature (IPv6): - Make IPv6-only clients wait for microdescs for relays, even if we were previously using descriptors (or were using them as a bridge) and have a cached descriptor for them. Implements ticket 23827. - When a consensus has IPv6 ORPorts, make IPv6-only clients use them, rather than waiting to download microdescriptors. Implements ticket 23827. o Minor features (cleanup): - Tor now deletes the CookieAuthFile and ExtORPortCookieAuthFile when it stops. Closes ticket 23271. o Minor features (defensive programming): - Most of the functions in Tor that free objects have been replaced with macros that free the objects and set the corresponding pointers to NULL. This change should help prevent a large class of dangling pointer bugs. Closes ticket 24337. - Where possible, the tor_free() macro now only evaluates its input once. Part of ticket 24337. - Check that microdesc ed25519 ids are non-zero in node_get_ed25519_id() before returning them. Implements ticket 24001, patch by "aruna1234". o Minor features (embedding): - Tor can now start with a preauthenticated control connection created by the process that launched it. This feature is meant for use by programs that want to launch and manage a Tor process without allowing other programs to manage it as well. For more information, see the __OwningControllerFD option documented in control-spec.txt. Closes ticket 23900. - On most errors that would cause Tor to exit, it now tries to return from the tor_main() function, rather than calling the system exit() function. Most users won't notice a difference here, but it should be significant for programs that run Tor inside a separate thread: they should now be able to survive Tor's exit conditions rather than having Tor shut down the entire process. Closes ticket 23848. - Applications that want to embed Tor can now tell Tor not to register any of its own POSIX signal handlers, using the __DisableSignalHandlers option. Closes ticket 24588. o Minor features (fallback directory list): - Avoid selecting fallbacks that change their IP addresses too often. Select more fallbacks by ignoring the Guard flag, and allowing lower cutoffs for the Running and V2Dir flags. Also allow a lower bandwidth, and a higher number of fallbacks per operator (5% of the list). Implements ticket 24785. - Update the fallback whitelist and blacklist based on opt-ins and relay changes. Closes tickets 22321, 24678, 22527, 24135, and 24695. o Minor features (fallback directory mirror configuration): - Add a nickname to each fallback in a C comment. This makes it easier for operators to find their relays, and allows stem to use nicknames to identify fallbacks. Implements ticket 24600. - Add a type and version header to the fallback directory mirror file. Also add a delimiter to the end of each fallback entry. This helps external parsers like stem and Relay Search. Implements ticket 24725. - Add an extrainfo cache flag for each fallback in a C comment. This allows stem to use fallbacks to fetch extra-info documents, rather than using authorities. Implements ticket 22759. - Add the generateFallbackDirLine.py script for automatically generating fallback directory mirror lines from relay fingerprints. No more typos! Add the lookupFallbackDirContact.py script for automatically looking up operator contact info from relay fingerprints. Implements ticket 24706, patch by teor and atagar. - Reject any fallback directory mirror that serves an expired consensus. Implements ticket 20942, patch by "minik". - Remove commas and equals signs from external string inputs to the fallback list. This avoids format confusion attacks. Implements ticket 24726. - Remove the "weight=10" line from fallback directory mirror entries. Ticket 24681 will maintain the current fallback weights by changing Tor's default fallback weight to 10. Implements ticket 24679. - Stop logging excessive information about fallback netblocks. Implements ticket 24791. o Minor features (forward-compatibility): - If a relay supports some link authentication protocol that we do not recognize, then include that relay's ed25519 key when telling other relays to extend to it. Previously, we treated future versions as if they were too old to support ed25519 link authentication. Closes ticket 20895. o Minor features (heartbeat): - Add onion service information to our heartbeat logs, displaying stats about the activity of configured onion services. Closes ticket 24896. o Minor features (instrumentation, development): - Add the MainloopStats option to allow developers to get instrumentation information from the main event loop via the heartbeat messages. We hope to use this to improve Tor's behavior when it's trying to sleep. Closes ticket 24605. o Minor features (log messages): - Improve a warning message that happens when we fail to re-parse an old router because of an expired certificate. Closes ticket 20020. - Make the log more quantitative when we hit MaxMemInQueues threshold exposing some values. Closes ticket 24501. o Minor features (logging, android): - Added support for the Android logging subsystem. Closes ticket 24362. o Minor features (performance): - Support predictive circuit building for onion service circuits with multiple layers of guards. Closes ticket 23101. - Use stdatomic.h where available, rather than mutexes, to implement atomic_counter_t. Closes ticket 23953. o Minor features (performance, 32-bit): - Improve performance on 32-bit systems by avoiding 64-bit division when calculating the timestamp in milliseconds for channel padding computations. Implements ticket 24613. - Improve performance on 32-bit systems by avoiding 64-bit division when timestamping cells and buffer chunks for OOM calculations. Implements ticket 24374. o Minor features (performance, OSX, iOS): - Use the mach_approximate_time() function (when available) to implement coarse monotonic time. Having a coarse time function should avoid a large number of system calls, and improve performance slightly, especially under load. Closes ticket 24427. o Minor features (performance, windows): - Improve performance on Windows Vista and Windows 7 by adjusting TCP send window size according to the recommendation from SIO_IDEAL_SEND_BACKLOG_QUERY. Closes ticket 22798. Patch from Vort. o Major features (relay): - Implement an option, ReducedExitPolicy, to allow an Tor exit relay operator to use a more reasonable ("reduced") exit policy, rather than the default one. If you want to run an exit node without thinking too hard about which ports to allow, this one is for you. Closes ticket 13605. Patch from Neel Chauhan. o Minor features (testing, debugging, embedding): - For development purposes, Tor now has a mode in which it runs for a few seconds, then stops, and starts again without exiting the process. This mode is meant to help us debug various issues with ticket 23847. To use this feature, compile with --enable-restart-debugging, and set the TOR_DEBUG_RESTART environment variable. This is expected to crash a lot, and is really meant for developers only. It will likely be removed in a future release. Implements ticket 24583. o Minor bugfix (network IPv6 test): - Tor's test scripts now check if "ping -6 ::1" works when the user runs "make test-network-all". Fixes bug 24677; bugfix on 0.2.9.3-alpha. Patch by "ffmancera". o Minor bugfixes (build, rust): - Fix output of autoconf checks to display success messages for Rust dependencies and a suitable rustc compiler version. Fixes bug 24612; bugfix on 0.3.1.3-alpha. - When building with Rust on OSX, link against libresolv, to work around the issue at https://github.com/rust-lang/rust/issues/46797. Fixes bug 24652; bugfix on 0.3.1.1-alpha. - Don't pass the --quiet option to cargo: it seems to suppress some errors, which is not what we want to do when building. Fixes bug 24518; bugfix on 0.3.1.7. - Build correctly when building from outside Tor's source tree with the TOR_RUST_DEPENDENCIES option set. Fixes bug 22768; bugfix on 0.3.1.7. o Minor bugfixes (directory authorities, IPv6): - When creating a routerstatus (vote) from a routerinfo (descriptor), set the IPv6 address to the unspecified IPv6 address, and explicitly initialize the port to zero. Fixes bug 24488; bugfix on 0.2.4.1-alpha. o Minor bugfixes (fallback directory mirrors): - Make updateFallbackDirs.py search harder for python. (Some OSs don't put it in /usr/bin.) Fixes bug 24708; bugfix on 0.2.8.1-alpha. o Minor bugfixes (hibernation, bandwidth accounting, shutdown): - When hibernating, close connections normally and allow them to flush. Fixes bug 23571; bugfix on 0.2.4.7-alpha. Also fixes bug 7267. - Do not attempt to launch self-reachability tests when entering hibernation. Fixes a case of bug 12062; bugfix on 0.0.9pre5. - Resolve several bugs related to descriptor fetching on bridge clients with bandwidth accounting enabled. (This combination is not recommended!) Fixes a case of bug 12062; bugfix on 0.2.0.3-alpha. - When hibernating, do not attempt to launch DNS checks. Fixes a case of bug 12062; bugfix on 0.1.2.2-alpha. - When hibernating, do not try to upload or download descriptors. Fixes a case of bug 12062; bugfix on 0.0.9pre5. o Minor bugfixes (IPv6, bridges): - Tor now always sets IPv6 preferences for bridges. Fixes bug 24573; bugfix on 0.2.8.2-alpha. - Tor now sets IPv6 address in the routerstatus as well as in the router descriptors when updating addresses for a bridge. Closes ticket 24572; bugfix on 0.2.4.5-alpha. Patch by "ffmancera". o Minor bugfixes (linux seccomp2 sandbox): - When running with the sandbox enabled, reload configuration files correctly even when %include was used. Previously we would crash. Fixes bug 22605; bugfix on 0.3.1. Patch from Daniel Pinto. o Minor bugfixes (memory leaks): - Avoid possible at-exit memory leaks related to use of Libevent's event_base_once() function. (This function tends to leak memory if the event_base is closed before the event fires.) Fixes bug 24584; bugfix on 0.2.8.1-alpha. - Fix a harmless memory leak in tor-resolve. Fixes bug 24582; bugfix on 0.2.1.1-alpha. o Minor bugfixes (OSX): - Don't exit the Tor process if setrlimit() fails to change the file limit (which can happen sometimes on some versions of OSX). Fixes bug 21074; bugfix on 0.0.9pre5. o Minor bugfixes (performance, fragile-hardening): - Improve the performance of our consensus-diff application code when Tor is built with the --enable-fragile-hardening option set. Fixes bug 24826; bugfix on 0.3.1.1-alpha. o Minor bugfixes (performance, timeouts): - Consider circuits for timeout as soon as they complete a hop. This is more accurate than applying the timeout in circuit_expire_building() because that function is only called once per second, which is now too slow for typical timeouts on the current network. Fixes bug 23114; bugfix on 0.2.2.2-alpha. - Use onion service circuits (and other circuits longer than 3 hops) to calculate a circuit build timeout. Previously, Tor only calculated its build timeout based on circuits that planned to be exactly 3 hops long. With this change, we include measurements from all circuits at the point where they complete their third hop. Fixes bug 23100; bugfix on 0.2.2.2-alpha. o Minor bugfixes (testing): - Give out Exit flags in bootstrapping networks. Fixes bug 24137; bugfix on 0.2.3.1-alpha. - Fix a memory leak in the scheduler/loop_kist unit test. Fixes bug 25005; bugfix on 0.3.2.7-rc. o Code simplification and refactoring: - Remove /usr/athena from search path in configure.ac. Closes ticket 24363. - Remove duplicate code in node_has_curve25519_onion_key() and node_get_curve25519_onion_key(), and add a check for a zero microdesc curve25519 onion key. Closes ticket 23966, patch by "aruna1234" and teor. - Rewrite channel_rsa_id_group_set_badness to reduce temporary memory allocations with large numbers of OR connections (e.g. relays). Closes ticket 24119. - Separate the function that deletes ephemeral files when Tor stops gracefully. - Small changes to Tor's buf_t API to make it suitable for use as a general-purpose safe string constructor. Closes ticket 22342. - Switch -Wnormalized=id to -Wnormalized=nfkc in configure.ac to avoid source code identifier confusion. Closes ticket 24467. - The tor_git_revision[] constant no longer needs to be redeclared by everything that links against the rest of Tor. Done as part of ticket 23845, to simplify our external API. - We make extend_info_from_node() use node_get_curve25519_onion_key() introduced in ticket 23577 to access the curve25519 public keys rather than accessing it directly. Closes ticket 23760. Patch by Neel Chauhan. - Add a function to log channels' scheduler state changes to aid debugging efforts. Closes ticket 24531. o Documentation: - Add documentation on how to build tor with Rust dependencies without having to be online. Closes ticket 22907; bugfix on 0.3.0.3-alpha. - Clarify the behavior of RelayBandwidth{Rate,Burst} with client traffic. Closes ticket 24318. - Document that OutboundBindAddress doesn't apply to DNS requests. Closes ticket 22145. Patch from Aruna Maurya. - Document that operators who run more than one relay or bridge are expected to set MyFamily and ContactInfo correctly. Closes ticket 24526. o Code simplification and refactoring (channels): - Remove the incoming and outgoing channel queues. These were never used, but still took up a step in our fast path. - The majority of the channel unit tests have been rewritten and the code coverage has now been raised to 83.6% for channel.c. Closes ticket 23709. - Remove other dead code from the channel subsystem: All together, this cleanup has removed more than 1500 lines of code overall and adding very little except for unit test. o Code simplification and refactoring (circuit rendezvous): - Split the client-side rendezvous circuit lookup into two functions: one that returns only established circuits and another that returns all kinds of circuits. Closes ticket 23459. o Code simplification and refactoring (controller): - Make most of the variables in networkstatus_getinfo_by_purpose() const. Implements ticket 24489. Changes in version 0.3.2.9 - 2018-01-09 Tor 0.3.2.9 is the first stable release in the 0.3.2 series. The 0.3.2 series includes our long-anticipated new onion service design, with numerous security features. (For more information, see our blog post at https://blog.torproject.org/fall-harvest.) We also have a new circuit scheduler algorithm for improved performance on relays everywhere (see https://blog.torproject.org/kist-and-tell), along with many smaller features and bugfixes. Per our stable release policy, we plan to support each stable release series for at least the next nine months, or for three months after the first stable release of the next series: whichever is longer. If you need a release with long-term support, we recommend that you stay with the 0.2.9 series. Below is a list of the changes since 0.3.2.8-rc. For a list of all changes since 0.3.1, see the ReleaseNotes file. o Minor features (fallback directory mirrors): - The fallback directory list has been re-generated based on the current status of the network. Tor uses fallback directories to bootstrap when it doesn't yet have up-to-date directory information. Closes ticket 24801. - Make the default DirAuthorityFallbackRate 0.1, so that clients prefer to bootstrap from fallback directory mirrors. This is a follow-up to 24679, which removed weights from the default fallbacks. Implements ticket 24681. o Minor features (geoip): - Update geoip and geoip6 to the January 5 2018 Maxmind GeoLite2 Country database. o Minor bugfixes (address selection): - When the fascist_firewall_choose_address_ functions don't find a reachable address, set the returned address to the null address and port. This is a precautionary measure, because some callers do not check the return value. Fixes bug 24736; bugfix on 0.2.8.2-alpha. o Minor bugfixes (compilation): - Resolve a few shadowed-variable warnings in the onion service code. Fixes bug 24634; bugfix on 0.3.2.1-alpha. o Minor bugfixes (portability, msvc): - Fix a bug in the bit-counting parts of our timing-wheel code on MSVC. (Note that MSVC is still not a supported build platform, due to cryptographic timing channel risks.) Fixes bug 24633; bugfix on 0.2.9.1-alpha. Changes in version 0.3.2.8-rc - 2017-12-21 Tor 0.3.2.8-rc fixes a pair of bugs in the KIST and KISTLite schedulers that had led servers under heavy load to overload their outgoing connections. All relay operators running earlier 0.3.2.x versions should upgrade. This version also includes a mitigation for over-full DESTROY queues leading to out-of-memory conditions: if it works, we will soon backport it to earlier release series. This is the second release candidate in the 0.3.2 series. If we find no new bugs or regression here, then the first stable 0.3.2 release will be nearly identical to this. o Major bugfixes (KIST, scheduler): - The KIST scheduler did not correctly account for data already enqueued in each connection's send socket buffer, particularly in cases when the TCP/IP congestion window was reduced between scheduler calls. This situation lead to excessive per-connection buffering in the kernel, and a potential memory DoS. Fixes bug 24665; bugfix on 0.3.2.1-alpha. o Minor features (geoip): - Update geoip and geoip6 to the December 6 2017 Maxmind GeoLite2 Country database. o Minor bugfixes (hidden service v3): - Bump hsdir_spread_store parameter from 3 to 4 in order to increase the probability of reaching a service for a client missing microdescriptors. Fixes bug 24425; bugfix on 0.3.2.1-alpha. o Minor bugfixes (memory usage): - When queuing DESTROY cells on a channel, only queue the circuit-id and reason fields: not the entire 514-byte cell. This fix should help mitigate any bugs or attacks that fill up these queues, and free more RAM for other uses. Fixes bug 24666; bugfix on 0.2.5.1-alpha. o Minor bugfixes (scheduler, KIST): - Use a sane write limit for KISTLite when writing onto a connection buffer instead of using INT_MAX and shoving as much as it can. Because the OOM handler cleans up circuit queues, we are better off at keeping them in that queue instead of the connection's buffer. Fixes bug 24671; bugfix on 0.3.2.1-alpha. Changes in version 0.3.2.7-rc - 2017-12-14 Tor 0.3.2.7-rc fixes various bugs in earlier versions of Tor, including some that could affect reliability or correctness. This is the first release candidate in the 0.3.2 series. If we find no new bugs or regression here, then the first stable 0.3.2. release will be nearly identical to this. o Major bugfixes (circuit prediction): - Fix circuit prediction logic so that a client doesn't treat a port as being "handled" by a circuit if that circuit already has isolation settings on it. This change should make Tor clients more responsive by improving their chances of having a pre-created circuit ready for use when a request arrives. Fixes bug 18859; bugfix on 0.2.3.3-alpha. o Minor features (logging): - Provide better warnings when the getrandom() syscall fails. Closes ticket 24500. o Minor features (portability): - Tor now compiles correctly on arm64 with libseccomp-dev installed. (It doesn't yet work with the sandbox enabled.) Closes ticket 24424. o Minor bugfixes (bridge clients, bootstrap): - Retry directory downloads when we get our first bridge descriptor during bootstrap or while reconnecting to the network. Keep retrying every time we get a bridge descriptor, until we have a reachable bridge. Fixes part of bug 24367; bugfix on 0.2.0.3-alpha. - Stop delaying bridge descriptor fetches when we have cached bridge descriptors. Instead, only delay bridge descriptor fetches when we have at least one reachable bridge. Fixes part of bug 24367; bugfix on 0.2.0.3-alpha. - Stop delaying directory fetches when we have cached bridge descriptors. Instead, only delay bridge descriptor fetches when all our bridges are definitely unreachable. Fixes part of bug 24367; bugfix on 0.2.0.3-alpha. o Minor bugfixes (compilation): - Fix a signed/unsigned comparison warning introduced by our fix to TROVE-2017-009. Fixes bug 24480; bugfix on 0.2.5.16. o Minor bugfixes (correctness): - Fix several places in our codebase where a C compiler would be likely to eliminate a check, based on assuming that undefined behavior had not happened elsewhere in the code. These cases are usually a sign of redundant checking or dubious arithmetic. Found by Georg Koppen using the "STACK" tool from Wang, Zeldovich, Kaashoek, and Solar-Lezama. Fixes bug 24423; bugfix on various Tor versions. o Minor bugfixes (onion service v3): - Fix a race where an onion service would launch a new intro circuit after closing an old one, but fail to register it before freeing the previously closed circuit. This bug was making the service unable to find the established intro circuit and thus not upload its descriptor, thus making a service unavailable for up to 24 hours. Fixes bug 23603; bugfix on 0.3.2.1-alpha. o Minor bugfixes (scheduler, KIST): - Properly set the scheduler state of an unopened channel in the KIST scheduler main loop. This prevents a harmless but annoying log warning. Fixes bug 24502; bugfix on 0.3.2.4-alpha. - Avoid a possible integer overflow when computing the available space on the TCP buffer of a channel. This had no security implications; but could make KIST allow too many cells on a saturated connection. Fixes bug 24590; bugfix on 0.3.2.1-alpha. - Downgrade to "info" a harmless warning about the monotonic time moving backwards: This can happen on platform not supporting monotonic time. Fixes bug 23696; bugfix on 0.3.2.1-alpha. Changes in version 0.3.2.6-alpha - 2017-12-01 This version of Tor is the latest in the 0.3.2 alpha series. It includes fixes for several important security issues. All Tor users should upgrade to this release, or to one of the other releases coming out today. o Major bugfixes (security): - Fix a denial of service bug where an attacker could use a malformed directory object to cause a Tor instance to pause while OpenSSL would try to read a passphrase from the terminal. (Tor instances run without a terminal, which is the case for most Tor packages, are not impacted.) Fixes bug 24246; bugfix on every version of Tor. Also tracked as TROVE-2017-011 and CVE-2017-8821. Found by OSS-Fuzz as testcase 6360145429790720. - Fix a denial of service issue where an attacker could crash a directory authority using a malformed router descriptor. Fixes bug 24245; bugfix on 0.2.9.4-alpha. Also tracked as TROVE-2017-010 and CVE-2017-8820. - When checking for replays in the INTRODUCE1 cell data for a (legacy) onion service, correctly detect replays in the RSA- encrypted part of the cell. We were previously checking for replays on the entire cell, but those can be circumvented due to the malleability of Tor's legacy hybrid encryption. This fix helps prevent a traffic confirmation attack. Fixes bug 24244; bugfix on 0.2.4.1-alpha. This issue is also tracked as TROVE-2017-009 and CVE-2017-8819. o Major bugfixes (security, onion service v2): - Fix a use-after-free error that could crash v2 Tor onion services when they failed to open circuits while expiring introduction points. Fixes bug 24313; bugfix on 0.2.7.2-alpha. This issue is also tracked as TROVE-2017-013 and CVE-2017-8823. o Major bugfixes (security, relay): - When running as a relay, make sure that we never build a path through ourselves, even in the case where we have somehow lost the version of our descriptor appearing in the consensus. Fixes part of bug 21534; bugfix on 0.2.0.1-alpha. This issue is also tracked as TROVE-2017-012 and CVE-2017-8822. - When running as a relay, make sure that we never choose ourselves as a guard. Fixes part of bug 21534; bugfix on 0.3.0.1-alpha. This issue is also tracked as TROVE-2017-012 and CVE-2017-8822. o Minor feature (relay statistics): - Change relay bandwidth reporting stats interval from 4 hours to 24 hours in order to reduce the efficiency of guard discovery attacks. Fixes ticket 23856. o Minor features (directory authority): - Add an IPv6 address for the "bastet" directory authority. Closes ticket 24394. o Minor bugfixes (client): - By default, do not enable storage of client-side DNS values. These values were unused by default previously, but they should not have been cached at all. Fixes bug 24050; bugfix on 0.2.6.3-alpha. Changes in version 0.3.1.9 - 2017-12-01: Tor 0.3.1.9 backports important security and stability fixes from the 0.3.2 development series. All Tor users should upgrade to this release, or to another of the releases coming out today. o Major bugfixes (security, backport from 0.3.2.6-alpha): - Fix a denial of service bug where an attacker could use a malformed directory object to cause a Tor instance to pause while OpenSSL would try to read a passphrase from the terminal. (Tor instances run without a terminal, which is the case for most Tor packages, are not impacted.) Fixes bug 24246; bugfix on every version of Tor. Also tracked as TROVE-2017-011 and CVE-2017-8821. Found by OSS-Fuzz as testcase 6360145429790720. - Fix a denial of service issue where an attacker could crash a directory authority using a malformed router descriptor. Fixes bug 24245; bugfix on 0.2.9.4-alpha. Also tracked as TROVE-2017-010 and CVE-2017-8820. - When checking for replays in the INTRODUCE1 cell data for a (legacy) onion service, correctly detect replays in the RSA- encrypted part of the cell. We were previously checking for replays on the entire cell, but those can be circumvented due to the malleability of Tor's legacy hybrid encryption. This fix helps prevent a traffic confirmation attack. Fixes bug 24244; bugfix on 0.2.4.1-alpha. This issue is also tracked as TROVE-2017-009 and CVE-2017-8819. o Major bugfixes (security, onion service v2, backport from 0.3.2.6-alpha): - Fix a use-after-free error that could crash v2 Tor onion services when they failed to open circuits while expiring introduction points. Fixes bug 24313; bugfix on 0.2.7.2-alpha. This issue is also tracked as TROVE-2017-013 and CVE-2017-8823. o Major bugfixes (security, relay, backport from 0.3.2.6-alpha): - When running as a relay, make sure that we never build a path through ourselves, even in the case where we have somehow lost the version of our descriptor appearing in the consensus. Fixes part of bug 21534; bugfix on 0.2.0.1-alpha. This issue is also tracked as TROVE-2017-012 and CVE-2017-8822. - When running as a relay, make sure that we never choose ourselves as a guard. Fixes part of bug 21534; bugfix on 0.3.0.1-alpha. This issue is also tracked as TROVE-2017-012 and CVE-2017-8822. o Major bugfixes (exit relays, DNS, backport from 0.3.2.4-alpha): - Fix an issue causing DNS to fail on high-bandwidth exit nodes, making them nearly unusable. Fixes bugs 21394 and 18580; bugfix on 0.1.2.2-alpha, which introduced eventdns. Thanks to Dhalgren for identifying and finding a workaround to this bug and to Moritz, Arthur Edelstein, and Roger for helping to track it down and analyze it. o Minor features (bridge): - Bridges now include notice in their descriptors that they are bridges, and notice of their distribution status, based on their publication settings. Implements ticket 18329. For more fine- grained control of how a bridge is distributed, upgrade to 0.3.2.x or later. o Minor features (directory authority, backport from 0.3.2.6-alpha): - Add an IPv6 address for the "bastet" directory authority. Closes ticket 24394. o Minor features (geoip): - Update geoip and geoip6 to the November 6 2017 Maxmind GeoLite2 Country database. o Minor bugfix (relay address resolution, backport from 0.3.2.1-alpha): - Avoid unnecessary calls to directory_fetches_from_authorities() on relays, to prevent spurious address resolutions and descriptor rebuilds. This is a mitigation for bug 21789. Fixes bug 23470; bugfix on in 0.2.8.1-alpha. o Minor bugfixes (compilation, backport from 0.3.2.1-alpha): - Fix unused variable warnings in donna's Curve25519 SSE2 code. Fixes bug 22895; bugfix on 0.2.7.2-alpha. o Minor bugfixes (logging, relay shutdown, annoyance, backport from 0.3.2.2-alpha): - When a circuit is marked for close, do not attempt to package any cells for channels on that circuit. Previously, we would detect this condition lower in the call stack, when we noticed that the circuit had no attached channel, and log an annoying message. Fixes bug 8185; bugfix on 0.2.5.4-alpha. o Minor bugfixes (onion service, backport from 0.3.2.5-alpha): - Rename the consensus parameter "hsdir-interval" to "hsdir_interval" so it matches dir-spec.txt. Fixes bug 24262; bugfix on 0.3.1.1-alpha. o Minor bugfixes (relay, crash, backport from 0.3.2.4-alpha): - Avoid a crash when transitioning from client mode to bridge mode. Previously, we would launch the worker threads whenever our "public server" mode changed, but not when our "server" mode changed. Fixes bug 23693; bugfix on 0.2.6.3-alpha. Changes in version 0.3.0.13 - 2017-12-01 Tor 0.3.0.13 backports important security and stability bugfixes from later Tor releases. All Tor users should upgrade to this release, or to another of the releases coming out today. Note: the Tor 0.3.0 series will no longer be supported after 26 Jan 2018. If you need a release with long-term support, please stick with the 0.2.9 series. Otherwise, please upgrade to 0.3.1 or later. o Major bugfixes (security, backport from 0.3.2.6-alpha): - Fix a denial of service bug where an attacker could use a malformed directory object to cause a Tor instance to pause while OpenSSL would try to read a passphrase from the terminal. (Tor instances run without a terminal, which is the case for most Tor packages, are not impacted.) Fixes bug 24246; bugfix on every version of Tor. Also tracked as TROVE-2017-011 and CVE-2017-8821. Found by OSS-Fuzz as testcase 6360145429790720. - Fix a denial of service issue where an attacker could crash a directory authority using a malformed router descriptor. Fixes bug 24245; bugfix on 0.2.9.4-alpha. Also tracked as TROVE-2017-010 and CVE-2017-8820. - When checking for replays in the INTRODUCE1 cell data for a (legacy) onion service, correctly detect replays in the RSA- encrypted part of the cell. We were previously checking for replays on the entire cell, but those can be circumvented due to the malleability of Tor's legacy hybrid encryption. This fix helps prevent a traffic confirmation attack. Fixes bug 24244; bugfix on 0.2.4.1-alpha. This issue is also tracked as TROVE-2017-009 and CVE-2017-8819. o Major bugfixes (security, onion service v2, backport from 0.3.2.6-alpha): - Fix a use-after-free error that could crash v2 Tor onion services when they failed to open circuits while expiring introduction points. Fixes bug 24313; bugfix on 0.2.7.2-alpha. This issue is also tracked as TROVE-2017-013 and CVE-2017-8823. o Major bugfixes (security, relay, backport from 0.3.2.6-alpha): - When running as a relay, make sure that we never build a path through ourselves, even in the case where we have somehow lost the version of our descriptor appearing in the consensus. Fixes part of bug 21534; bugfix on 0.2.0.1-alpha. This issue is also tracked as TROVE-2017-012 and CVE-2017-8822. - When running as a relay, make sure that we never choose ourselves as a guard. Fixes part of bug 21534; bugfix on 0.3.0.1-alpha. This issue is also tracked as TROVE-2017-012 and CVE-2017-8822. o Major bugfixes (exit relays, DNS, backport from 0.3.2.4-alpha): - Fix an issue causing DNS to fail on high-bandwidth exit nodes, making them nearly unusable. Fixes bugs 21394 and 18580; bugfix on 0.1.2.2-alpha, which introduced eventdns. Thanks to Dhalgren for identifying and finding a workaround to this bug and to Moritz, Arthur Edelstein, and Roger for helping to track it down and analyze it. o Minor features (security, windows, backport from 0.3.1.1-alpha): - Enable a couple of pieces of Windows hardening: one (HeapEnableTerminationOnCorruption) that has been on-by-default since Windows 8, and unavailable before Windows 7; and one (PROCESS_DEP_DISABLE_ATL_THUNK_EMULATION) which we believe doesn't affect us, but shouldn't do any harm. Closes ticket 21953. o Minor features (bridge, backport from 0.3.1.9): - Bridges now include notice in their descriptors that they are bridges, and notice of their distribution status, based on their publication settings. Implements ticket 18329. For more fine- grained control of how a bridge is distributed, upgrade to 0.3.2.x or later. o Minor features (directory authority, backport from 0.3.2.6-alpha): - Add an IPv6 address for the "bastet" directory authority. Closes ticket 24394. o Minor features (geoip): - Update geoip and geoip6 to the November 6 2017 Maxmind GeoLite2 Country database. o Minor bugfix (relay address resolution, backport from 0.3.2.1-alpha): - Avoid unnecessary calls to directory_fetches_from_authorities() on relays, to prevent spurious address resolutions and descriptor rebuilds. This is a mitigation for bug 21789. Fixes bug 23470; bugfix on in 0.2.8.1-alpha. o Minor bugfixes (compilation, backport from 0.3.2.1-alpha): - Fix unused variable warnings in donna's Curve25519 SSE2 code. Fixes bug 22895; bugfix on 0.2.7.2-alpha. o Minor bugfixes (logging, relay shutdown, annoyance, backport from 0.3.2.2-alpha): - When a circuit is marked for close, do not attempt to package any cells for channels on that circuit. Previously, we would detect this condition lower in the call stack, when we noticed that the circuit had no attached channel, and log an annoying message. Fixes bug 8185; bugfix on 0.2.5.4-alpha. o Minor bugfixes (relay, crash, backport from 0.3.2.4-alpha): - Avoid a crash when transitioning from client mode to bridge mode. Previously, we would launch the worker threads whenever our "public server" mode changed, but not when our "server" mode changed. Fixes bug 23693; bugfix on 0.2.6.3-alpha. o Minor bugfixes (testing, backport from 0.3.1.6-rc): - Fix an undersized buffer in test-memwipe.c. Fixes bug 23291; bugfix on 0.2.7.2-alpha. Found and patched by Ties Stuij. Changes in version 0.2.9.14 - 2017-12-01 Tor 0.3.0.13 backports important security and stability bugfixes from later Tor releases. All Tor users should upgrade to this release, or to another of the releases coming out today. o Major bugfixes (exit relays, DNS, backport from 0.3.2.4-alpha): - Fix an issue causing DNS to fail on high-bandwidth exit nodes, making them nearly unusable. Fixes bugs 21394 and 18580; bugfix on 0.1.2.2-alpha, which introduced eventdns. Thanks to Dhalgren for identifying and finding a workaround to this bug and to Moritz, Arthur Edelstein, and Roger for helping to track it down and analyze it. o Major bugfixes (security, backport from 0.3.2.6-alpha): - Fix a denial of service bug where an attacker could use a malformed directory object to cause a Tor instance to pause while OpenSSL would try to read a passphrase from the terminal. (Tor instances run without a terminal, which is the case for most Tor packages, are not impacted.) Fixes bug 24246; bugfix on every version of Tor. Also tracked as TROVE-2017-011 and CVE-2017-8821. Found by OSS-Fuzz as testcase 6360145429790720. - Fix a denial of service issue where an attacker could crash a directory authority using a malformed router descriptor. Fixes bug 24245; bugfix on 0.2.9.4-alpha. Also tracked as TROVE-2017-010 and CVE-2017-8820. - When checking for replays in the INTRODUCE1 cell data for a (legacy) onion service, correctly detect replays in the RSA- encrypted part of the cell. We were previously checking for replays on the entire cell, but those can be circumvented due to the malleability of Tor's legacy hybrid encryption. This fix helps prevent a traffic confirmation attack. Fixes bug 24244; bugfix on 0.2.4.1-alpha. This issue is also tracked as TROVE-2017-009 and CVE-2017-8819. o Major bugfixes (security, onion service v2, backport from 0.3.2.6-alpha): - Fix a use-after-free error that could crash v2 Tor onion services when they failed to open circuits while expiring introduction points. Fixes bug 24313; bugfix on 0.2.7.2-alpha. This issue is also tracked as TROVE-2017-013 and CVE-2017-8823. o Major bugfixes (security, relay, backport from 0.3.2.6-alpha): - When running as a relay, make sure that we never build a path through ourselves, even in the case where we have somehow lost the version of our descriptor appearing in the consensus. Fixes part of bug 21534; bugfix on 0.2.0.1-alpha. This issue is also tracked as TROVE-2017-012 and CVE-2017-8822. o Minor features (bridge, backport from 0.3.1.9): - Bridges now include notice in their descriptors that they are bridges, and notice of their distribution status, based on their publication settings. Implements ticket 18329. For more fine- grained control of how a bridge is distributed, upgrade to 0.3.2.x or later. o Minor features (directory authority, backport from 0.3.2.6-alpha): - Add an IPv6 address for the "bastet" directory authority. Closes ticket 24394. o Minor features (geoip): - Update geoip and geoip6 to the November 6 2017 Maxmind GeoLite2 Country database. o Minor features (security, windows, backport from 0.3.1.1-alpha): - Enable a couple of pieces of Windows hardening: one (HeapEnableTerminationOnCorruption) that has been on-by-default since Windows 8, and unavailable before Windows 7; and one (PROCESS_DEP_DISABLE_ATL_THUNK_EMULATION) which we believe doesn't affect us, but shouldn't do any harm. Closes ticket 21953. o Minor bugfix (relay address resolution, backport from 0.3.2.1-alpha): - Avoid unnecessary calls to directory_fetches_from_authorities() on relays, to prevent spurious address resolutions and descriptor rebuilds. This is a mitigation for bug 21789. Fixes bug 23470; bugfix on in 0.2.8.1-alpha. o Minor bugfixes (compilation, backport from 0.3.2.1-alpha): - Fix unused variable warnings in donna's Curve25519 SSE2 code. Fixes bug 22895; bugfix on 0.2.7.2-alpha. o Minor bugfixes (logging, relay shutdown, annoyance, backport from 0.3.2.2-alpha): - When a circuit is marked for close, do not attempt to package any cells for channels on that circuit. Previously, we would detect this condition lower in the call stack, when we noticed that the circuit had no attached channel, and log an annoying message. Fixes bug 8185; bugfix on 0.2.5.4-alpha. o Minor bugfixes (relay, crash, backport from 0.3.2.4-alpha): - Avoid a crash when transitioning from client mode to bridge mode. Previously, we would launch the worker threads whenever our "public server" mode changed, but not when our "server" mode changed. Fixes bug 23693; bugfix on 0.2.6.3-alpha. o Minor bugfixes (testing, backport from 0.3.1.6-rc): - Fix an undersized buffer in test-memwipe.c. Fixes bug 23291; bugfix on 0.2.7.2-alpha. Found and patched by Ties Stuij. Changes in version 0.2.8.17 - 2017-12-01 Tor 0.2.8.17 backports important security and stability bugfixes from later Tor releases. All Tor users should upgrade to this release, or to another of the releases coming out today. Note: the Tor 0.2.8 series will no longer be supported after 1 Jan 2018. If you need a release with long-term support, please upgrade with the 0.2.9 series. Otherwise, please upgrade to 0.3.1 or later. o Major bugfixes (security, backport from 0.3.2.6-alpha): - Fix a denial of service bug where an attacker could use a malformed directory object to cause a Tor instance to pause while OpenSSL would try to read a passphrase from the terminal. (Tor instances run without a terminal, which is the case for most Tor packages, are not impacted.) Fixes bug 24246; bugfix on every version of Tor. Also tracked as TROVE-2017-011 and CVE-2017-8821. Found by OSS-Fuzz as testcase 6360145429790720. - When checking for replays in the INTRODUCE1 cell data for a (legacy) onion service, correctly detect replays in the RSA- encrypted part of the cell. We were previously checking for replays on the entire cell, but those can be circumvented due to the malleability of Tor's legacy hybrid encryption. This fix helps prevent a traffic confirmation attack. Fixes bug 24244; bugfix on 0.2.4.1-alpha. This issue is also tracked as TROVE-2017-009 and CVE-2017-8819. o Major bugfixes (security, onion service v2, backport from 0.3.2.6-alpha): - Fix a use-after-free error that could crash v2 Tor onion services when they failed to open circuits while expiring introduction points. Fixes bug 24313; bugfix on 0.2.7.2-alpha. This issue is also tracked as TROVE-2017-013 and CVE-2017-8823. o Major bugfixes (security, relay, backport from 0.3.2.6-alpha): - When running as a relay, make sure that we never build a path through ourselves, even in the case where we have somehow lost the version of our descriptor appearing in the consensus. Fixes part of bug 21534; bugfix on 0.2.0.1-alpha. This issue is also tracked as TROVE-2017-012 and CVE-2017-8822. o Minor features (bridge, backport from 0.3.1.9): - Bridges now include notice in their descriptors that they are bridges, and notice of their distribution status, based on their publication settings. Implements ticket 18329. For more fine- grained control of how a bridge is distributed, upgrade to 0.3.2.x or later. o Minor features (directory authority, backport from 0.3.2.6-alpha): - Add an IPv6 address for the "bastet" directory authority. Closes ticket 24394. o Minor features (geoip): - Update geoip and geoip6 to the November 6 2017 Maxmind GeoLite2 Country database. o Minor bugfixes (testing, backport from 0.3.1.6-rc): - Fix an undersized buffer in test-memwipe.c. Fixes bug 23291; bugfix on 0.2.7.2-alpha. Found and patched by Ties Stuij. Changes in version 0.2.5.16 - 2017-12-01 Tor 0.2.5.13 backports important security and stability bugfixes from later Tor releases. All Tor users should upgrade to this release, or to another of the releases coming out today. Note: the Tor 0.2.5 series will no longer be supported after 1 May 2018. If you need a release with long-term support, please upgrade to the 0.2.9 series. Otherwise, please upgrade to 0.3.1 or later. o Major bugfixes (security, backport from 0.3.2.6-alpha): - Fix a denial of service bug where an attacker could use a malformed directory object to cause a Tor instance to pause while OpenSSL would try to read a passphrase from the terminal. (Tor instances run without a terminal, which is the case for most Tor packages, are not impacted.) Fixes bug 24246; bugfix on every version of Tor. Also tracked as TROVE-2017-011 and CVE-2017-8821. Found by OSS-Fuzz as testcase 6360145429790720. - When checking for replays in the INTRODUCE1 cell data for a (legacy) onion service, correctly detect replays in the RSA- encrypted part of the cell. We were previously checking for replays on the entire cell, but those can be circumvented due to the malleability of Tor's legacy hybrid encryption. This fix helps prevent a traffic confirmation attack. Fixes bug 24244; bugfix on 0.2.4.1-alpha. This issue is also tracked as TROVE-2017-009 and CVE-2017-8819. o Major bugfixes (security, relay, backport from 0.3.2.6-alpha): - When running as a relay, make sure that we never build a path through ourselves, even in the case where we have somehow lost the version of our descriptor appearing in the consensus. Fixes part of bug 21534; bugfix on 0.2.0.1-alpha. This issue is also tracked as TROVE-2017-012 and CVE-2017-8822. o Minor features (bridge, backport from 0.3.1.9): - Bridges now include notice in their descriptors that they are bridges, and notice of their distribution status, based on their publication settings. Implements ticket 18329. For more fine- grained control of how a bridge is distributed, upgrade to 0.3.2.x or later. o Minor features (geoip): - Update geoip and geoip6 to the November 6 2017 Maxmind GeoLite2 Country database. Changes in version 0.3.2.5-alpha - 2017-11-22 Tor 0.3.2.5-alpha is the fifth alpha release in the 0.3.2.x series. It fixes several stability and reliability bugs, including a fix for intermittent bootstrapping failures that some people have been seeing since the 0.3.0.x series. Please test this alpha out -- many of these fixes will soon be backported to stable Tor versions if no additional bugs are found in them. o Major bugfixes (bootstrapping): - Fetch descriptors aggressively whenever we lack enough to build circuits, regardless of how many descriptors we are missing. Previously, we would delay launching the fetch when we had fewer than 15 missing descriptors, even if some of those descriptors were blocking circuits from building. Fixes bug 23985; bugfix on 0.1.1.11-alpha. The effects of this bug became worse in 0.3.0.3-alpha, when we began treating missing descriptors from our primary guards as a reason to delay circuits. - Don't try fetching microdescriptors from relays that have failed to deliver them in the past. Fixes bug 23817; bugfix on 0.3.0.1-alpha. o Minor features (directory authority): - Make the "Exit" flag assignment only depend on whether the exit policy allows connections to ports 80 and 443. Previously relays would get the Exit flag if they allowed connections to one of these ports and also port 6667. Resolves ticket 23637. o Minor features (geoip): - Update geoip and geoip6 to the November 6 2017 Maxmind GeoLite2 Country database. o Minor features (linux seccomp2 sandbox): - Update the sandbox rules so that they should now work correctly with Glibc 2.26. Closes ticket 24315. o Minor features (logging): - Downgrade a pair of log messages that could occur when an exit's resolver gave us an unusual (but not forbidden) response. Closes ticket 24097. - Improve the message we log when re-enabling circuit build timeouts after having received a consensus. Closes ticket 20963. o Minor bugfixes (compilation): - Fix a memory leak warning in one of the libevent-related configuration tests that could occur when manually specifying -fsanitize=address. Fixes bug 24279; bugfix on 0.3.0.2-alpha. Found and patched by Alex Xu. - When detecting OpenSSL on Windows from our configure script, make sure to try linking with the ws2_32 library. Fixes bug 23783; bugfix on 0.3.2.2-alpha. o Minor bugfixes (control port, linux seccomp2 sandbox): - Avoid a crash when attempting to use the seccomp2 sandbox together with the OwningControllerProcess feature. Fixes bug 24198; bugfix on 0.2.5.1-alpha. o Minor bugfixes (control port, onion services): - Report "FAILED" instead of "UPLOAD_FAILED" "FAILED" for the HS_DESC event when a service is not able to upload a descriptor. Fixes bug 24230; bugfix on 0.2.7.1-alpha. o Minor bugfixes (directory cache): - Recover better from empty or corrupt files in the consensus cache directory. Fixes bug 24099; bugfix on 0.3.1.1-alpha. - When a consensus diff calculation is only partially successful, only record the successful parts as having succeeded. Partial success can happen if (for example) one compression method fails but the others succeed. Previously we misrecorded all the calculations as having succeeded, which would later cause a nonfatal assertion failure. Fixes bug 24086; bugfix on 0.3.1.1-alpha. o Minor bugfixes (logging): - Only log once if we notice that KIST support is gone. Fixes bug 24158; bugfix on 0.3.2.1-alpha. - Suppress a log notice when relay descriptors arrive. We already have a bootstrap progress for this so no need to log notice everytime tor receives relay descriptors. Microdescriptors behave the same. Fixes bug 23861; bugfix on 0.2.8.2-alpha. o Minor bugfixes (network layer): - When closing a connection via close_connection_immediately(), we mark it as "not blocked on bandwidth", to prevent later calls from trying to unblock it, and give it permission to read. This fixes a backtrace warning that can happen on relays under various circumstances. Fixes bug 24167; bugfix on 0.1.0.1-rc. o Minor bugfixes (onion services): - The introduction circuit was being timed out too quickly while waiting for the rendezvous circuit to complete. Keep the intro circuit around longer instead of timing out and reopening new ones constantly. Fixes bug 23681; bugfix on 0.2.4.8-alpha. - Rename the consensus parameter "hsdir-interval" to "hsdir_interval" so it matches dir-spec.txt. Fixes bug 24262; bugfix on 0.3.1.1-alpha. - Silence a warning about failed v3 onion descriptor uploads that can happen naturally under certain edge cases. Fixes part of bug 23662; bugfix on 0.3.2.1-alpha. o Minor bugfixes (tests): - Fix a memory leak in one of the bridge-distribution test cases. Fixes bug 24345; bugfix on 0.3.2.3-alpha. - Fix a bug in our fuzzing mock replacement for crypto_pk_checksig(), to correctly handle cases where a caller gives it an RSA key of under 160 bits. (This is not actually a bug in Tor itself, but rather in our fuzzing code.) Fixes bug 24247; bugfix on 0.3.0.3-alpha. Found by OSS-Fuzz as issue 4177. o Documentation: - Add notes in man page regarding OS support for the various scheduler types. Attempt to use less jargon in the scheduler section. Closes ticket 24254. Changes in version 0.3.2.4-alpha - 2017-11-08 Tor 0.3.2.4-alpha is the fourth alpha release in the 0.3.2.x series. It fixes several stability and reliability bugs, especially including a major reliability issue that has been plaguing fast exit relays in recent months. o Major bugfixes (exit relays, DNS): - Fix an issue causing DNS to fail on high-bandwidth exit nodes, making them nearly unusable. Fixes bugs 21394 and 18580; bugfix on 0.1.2.2-alpha, which introduced eventdns. Thanks to Dhalgren for identifying and finding a workaround to this bug and to Moritz, Arthur Edelstein, and Roger for helping to track it down and analyze it. o Major bugfixes (scheduler, channel): - Stop processing scheduled channels if they closed while flushing cells. This can happen if the write on the connection fails leading to the channel being closed while in the scheduler loop. Fixes bug 23751; bugfix on 0.3.2.1-alpha. o Minor features (logging, scheduler): - Introduce a SCHED_BUG() function to log extra information about the scheduler state if we ever catch a bug in the scheduler. Closes ticket 23753. o Minor features (removed deprecations): - The ClientDNSRejectInternalAddresses flag can once again be set in non-testing Tor networks, so long as they do not use the default directory authorities. This change also removes the deprecation of this flag from 0.2.9.2-alpha. Closes ticket 21031. o Minor features (testing): - Our fuzzing tests now test the encrypted portions of v3 onion service descriptors. Implements more of 21509. o Minor bugfixes (directory client): - On failure to download directory information, delay retry attempts by a random amount based on the "decorrelated jitter" algorithm. Our previous delay algorithm tended to produce extra-long delays too easily. Fixes bug 23816; bugfix on 0.2.9.1-alpha. o Minor bugfixes (IPv6, v3 single onion services): - Remove buggy code for IPv6-only v3 single onion services, and reject attempts to configure them. This release supports IPv4, dual-stack, and IPv6-only v3 onion services; and IPv4 and dual- stack v3 single onion services. Fixes bug 23820; bugfix on 0.3.2.1-alpha. o Minor bugfixes (logging, relay): - Give only a protocol warning when the ed25519 key is not consistent between the descriptor and microdescriptor of a relay. This can happen, for instance, if the relay has been flagged NoEdConsensus. Fixes bug 24025; bugfix on 0.3.2.1-alpha. o Minor bugfixes (manpage, onion service): - Document that the HiddenServiceNumIntroductionPoints option is 0-10 for v2 services and 0-20 for v3 services. Fixes bug 24115; bugfix on 0.3.2.1-alpha. o Minor bugfixes (memory leaks): - Fix a minor memory leak at exit in the KIST scheduler. This bug should have no user-visible impact. Fixes bug 23774; bugfix on 0.3.2.1-alpha. - Fix a memory leak when decrypting a badly formatted v3 onion service descriptor. Fixes bug 24150; bugfix on 0.3.2.1-alpha. Found by OSS-Fuzz; this is OSS-Fuzz issue 3994. o Minor bugfixes (onion services): - Cache some needed onion service client information instead of constantly computing it over and over again. Fixes bug 23623; bugfix on 0.3.2.1-alpha. - Properly retry HSv3 descriptor fetches when missing required directory information. Fixes bug 23762; bugfix on 0.3.2.1-alpha. o Minor bugfixes (path selection): - When selecting relays by bandwidth, avoid a rounding error that could sometimes cause load to be imbalanced incorrectly. Previously, we would always round upwards; now, we round towards the nearest integer. This had the biggest effect when a relay's weight adjustments should have given it weight 0, but it got weight 1 instead. Fixes bug 23318; bugfix on 0.2.4.3-alpha. - When calculating the fraction of nodes that have descriptors, and all nodes in the network have zero bandwidths, count the number of nodes instead. Fixes bug 23318; bugfix on 0.2.4.10-alpha. - Actually log the total bandwidth in compute_weighted_bandwidths(). Fixes bug 24170; bugfix on 0.2.4.3-alpha. o Minor bugfixes (relay, crash): - Avoid a crash when transitioning from client mode to bridge mode. Previously, we would launch the worker threads whenever our "public server" mode changed, but not when our "server" mode changed. Fixes bug 23693; bugfix on 0.2.6.3-alpha. o Minor bugfixes (testing): - Fix a spurious fuzzing-only use of an uninitialized value. Found by Brian Carpenter. Fixes bug 24082; bugfix on 0.3.0.3-alpha. - Test that IPv6-only clients can use microdescriptors when running "make test-network-all". Requires chutney master 61c28b9 or later. Closes ticket 24109. Changes in version 0.3.2.3-alpha - 2017-10-27 Tor 0.3.2.3-alpha is the third release in the 0.3.2 series. It fixes numerous small bugs in earlier versions of 0.3.2.x, and adds a new directory authority, Bastet. o Directory authority changes: - Add "Bastet" as a ninth directory authority to the default list. Closes ticket 23910. - The directory authority "Longclaw" has changed its IP address. Closes ticket 23592. o Minor features (bridge): - Bridge relays can now set the BridgeDistribution config option to add a "bridge-distribution-request" line to their bridge descriptor, which tells BridgeDB how they'd like their bridge address to be given out. (Note that as of Oct 2017, BridgeDB does not yet implement this feature.) As a side benefit, this feature provides a way to distinguish bridge descriptors from non-bridge descriptors. Implements tickets 18329. o Minor features (client, entry guards): - Improve log messages when missing descriptors for primary guards. Resolves ticket 23670. o Minor features (geoip): - Update geoip and geoip6 to the October 4 2017 Maxmind GeoLite2 Country database. o Minor bugfixes (bridge): - Overwrite the bridge address earlier in the process of retrieving its descriptor, to make sure we reach it on the configured address. Fixes bug 20532; bugfix on 0.2.0.10-alpha. o Minor bugfixes (documentation): - Document better how to read gcov, and what our gcov postprocessing scripts do. Fixes bug 23739; bugfix on 0.2.9.1-alpha. o Minor bugfixes (entry guards): - Tor now updates its guard state when it reads a consensus regardless of whether it's missing descriptors. That makes tor use its primary guards to fetch descriptors in some edge cases where it would previously have used fallback directories. Fixes bug 23862; bugfix on 0.3.0.1-alpha. o Minor bugfixes (hidden service client): - When handling multiple SOCKS request for the same .onion address, only fetch the service descriptor once. - When a descriptor fetch fails with a non-recoverable error, close all pending SOCKS requests for that .onion. Fixes bug 23653; bugfix on 0.3.2.1-alpha. o Minor bugfixes (hidden service): - Always regenerate missing hidden service public key files. Prior to this, if the public key was deleted from disk, it wouldn't get recreated. Fixes bug 23748; bugfix on 0.3.2.2-alpha. Patch from "cathugger". - Make sure that we have a usable ed25519 key when the intro point relay supports ed25519 link authentication. Fixes bug 24002; bugfix on 0.3.2.1-alpha. o Minor bugfixes (hidden service, v2): - When reloading configured hidden services, copy all information from the old service object. Previously, some data was omitted, causing delays in descriptor upload, and other bugs. Fixes bug 23790; bugfix on 0.2.1.9-alpha. o Minor bugfixes (memory safety, defensive programming): - Clear the target address when node_get_prim_orport() returns early. Fixes bug 23874; bugfix on 0.2.8.2-alpha. o Minor bugfixes (relay): - Avoid a BUG warning when receiving a dubious CREATE cell while an option transition is in progress. Fixes bug 23952; bugfix on 0.3.2.1-alpha. o Minor bugfixes (testing): - Adjust the GitLab CI configuration to more closely match that of Travis CI. Fixes bug 23757; bugfix on 0.3.2.2-alpha. - Prevent scripts/test/coverage from attempting to move gcov output to the root directory. Fixes bug 23741; bugfix on 0.2.5.1-alpha. - When running unit tests as root, skip a test that would fail because it expects a permissions error. This affects some continuous integration setups. Fixes bug 23758; bugfix on 0.3.2.2-alpha. - Stop unconditionally mirroring the tor repository in GitLab CI. This prevented developers from enabling GitLab CI on master. Fixes bug 23755; bugfix on 0.3.2.2-alpha. - Fix the hidden service v3 descriptor decoding fuzzing to use the latest decoding API correctly. Fixes bug 21509; bugfix on 0.3.2.1-alpha. o Minor bugfixes (warnings): - When we get an HTTP request on a SOCKS port, tell the user about the new HTTPTunnelPort option. Previously, we would give a "Tor is not an HTTP Proxy" message, which stopped being true when HTTPTunnelPort was introduced. Fixes bug 23678; bugfix on 0.3.2.1-alpha. Changes in version 0.2.5.15 - 2017-10-25 Tor 0.2.5.15 backports a collection of bugfixes from later Tor release series. It also adds a new directory authority, Bastet. Note: the Tor 0.2.5 series will no longer be supported after 1 May 2018. If you need a release with long-term support, please upgrade to the 0.2.9 series. Otherwise, please upgrade to 0.3.1 or later. o Directory authority changes: - Add "Bastet" as a ninth directory authority to the default list. Closes ticket 23910. - The directory authority "Longclaw" has changed its IP address. Closes ticket 23592. o Major bugfixes (openbsd, denial-of-service, backport from 0.3.1.5-alpha): - Avoid an assertion failure bug affecting our implementation of inet_pton(AF_INET6) on certain OpenBSD systems whose strtol() handling of "0xx" differs from what we had expected. Fixes bug 22789; bugfix on 0.2.3.8-alpha. Also tracked as TROVE-2017-007. o Minor features (geoip): - Update geoip and geoip6 to the October 4 2017 Maxmind GeoLite2 Country database. o Minor bugfixes (defensive programming, undefined behavior, backport from 0.3.1.4-alpha): - Fix a memset() off the end of an array when packing cells. This bug should be harmless in practice, since the corrupted bytes are still in the same structure, and are always padding bytes, ignored, or immediately overwritten, depending on compiler behavior. Nevertheless, because the memset()'s purpose is to make sure that any other cell-handling bugs can't expose bytes to the network, we need to fix it. Fixes bug 22737; bugfix on 0.2.4.11-alpha. Fixes CID 1401591. o Build features (backport from 0.3.1.5-alpha): - Tor's repository now includes a Travis Continuous Integration (CI) configuration file (.travis.yml). This is meant to help new developers and contributors who fork Tor to a Github repository be better able to test their changes, and understand what we expect to pass. To use this new build feature, you must fork Tor to your Github account, then go into the "Integrations" menu in the repository settings for your fork and enable Travis, then push your changes. Closes ticket 22636. Changes in version 0.2.8.16 - 2017-10-25 Tor 0.2.8.16 backports a collection of bugfixes from later Tor release series, including a bugfix for a crash issue that had affected relays under memory pressure. It also adds a new directory authority, Bastet. Note: the Tor 0.2.8 series will no longer be supported after 1 Jan 2018. If you need a release with long-term support, please stick with the 0.2.9 series. Otherwise, please upgrade to 0.3.1 or later. o Directory authority changes: - Add "Bastet" as a ninth directory authority to the default list. Closes ticket 23910. - The directory authority "Longclaw" has changed its IP address. Closes ticket 23592. o Major bugfixes (relay, crash, assertion failure, backport from 0.3.2.2-alpha): - Fix a timing-based assertion failure that could occur when the circuit out-of-memory handler freed a connection's output buffer. Fixes bug 23690; bugfix on 0.2.6.1-alpha. o Minor features (directory authorities, backport from 0.3.2.2-alpha): - Remove longclaw's IPv6 address, as it will soon change. Authority IPv6 addresses were originally added in 0.2.8.1-alpha. This leaves 3/8 directory authorities with IPv6 addresses, but there are also 52 fallback directory mirrors with IPv6 addresses. Resolves 19760. o Minor features (geoip): - Update geoip and geoip6 to the October 4 2017 Maxmind GeoLite2 Country database. Changes in version 0.2.9.13 - 2017-10-25 Tor 0.2.9.13 backports a collection of bugfixes from later Tor release series, including a bugfix for a crash issue that had affected relays under memory pressure. It also adds a new directory authority, Bastet. o Directory authority changes: - Add "Bastet" as a ninth directory authority to the default list. Closes ticket 23910. - The directory authority "Longclaw" has changed its IP address. Closes ticket 23592. o Major bugfixes (relay, crash, assertion failure, backport from 0.3.2.2-alpha): - Fix a timing-based assertion failure that could occur when the circuit out-of-memory handler freed a connection's output buffer. Fixes bug 23690; bugfix on 0.2.6.1-alpha. o Minor features (directory authorities, backport from 0.3.2.2-alpha): - Remove longclaw's IPv6 address, as it will soon change. Authority IPv6 addresses were originally added in 0.2.8.1-alpha. This leaves 3/8 directory authorities with IPv6 addresses, but there are also 52 fallback directory mirrors with IPv6 addresses. Resolves 19760. o Minor features (geoip): - Update geoip and geoip6 to the October 4 2017 Maxmind GeoLite2 Country database. o Minor bugfixes (directory authority, backport from 0.3.1.5-alpha): - When a directory authority rejects a descriptor or extrainfo with a given digest, mark that digest as undownloadable, so that we do not attempt to download it again over and over. We previously tried to avoid downloading such descriptors by other means, but we didn't notice if we accidentally downloaded one anyway. This behavior became problematic in 0.2.7.2-alpha, when authorities began pinning Ed25519 keys. Fixes bug 22349; bugfix on 0.2.1.19-alpha. o Minor bugfixes (memory safety, backport from 0.3.2.3-alpha): - Clear the address when node_get_prim_orport() returns early. Fixes bug 23874; bugfix on 0.2.8.2-alpha. o Minor bugfixes (Windows service, backport from 0.3.1.6-rc): - When running as a Windows service, set the ID of the main thread correctly. Failure to do so made us fail to send log messages to the controller in 0.2.1.16-rc, slowed down controller event delivery in 0.2.7.3-rc and later, and crash with an assertion failure in 0.3.1.1-alpha. Fixes bug 23081; bugfix on 0.2.1.6-alpha. Patch and diagnosis from "Vort". Changes in version 0.3.0.12 - 2017-10-25 Tor 0.3.0.12 backports a collection of bugfixes from later Tor release series, including a bugfix for a crash issue that had affected relays under memory pressure. It also adds a new directory authority, Bastet. Note: the Tor 0.3.0 series will no longer be supported after 26 Jan 2018. If you need a release with long-term support, please stick with the 0.2.9 series. Otherwise, please upgrade to 0.3.1 or later. o Directory authority changes: - Add "Bastet" as a ninth directory authority to the default list. Closes ticket 23910. - The directory authority "Longclaw" has changed its IP address. Closes ticket 23592. o Major bugfixes (relay, crash, assertion failure, backport from 0.3.2.2-alpha): - Fix a timing-based assertion failure that could occur when the circuit out-of-memory handler freed a connection's output buffer. Fixes bug 23690; bugfix on 0.2.6.1-alpha. o Minor features (directory authorities, backport from 0.3.2.2-alpha): - Remove longclaw's IPv6 address, as it will soon change. Authority IPv6 addresses were originally added in 0.2.8.1-alpha. This leaves 3/8 directory authorities with IPv6 addresses, but there are also 52 fallback directory mirrors with IPv6 addresses. Resolves 19760. o Minor features (geoip): - Update geoip and geoip6 to the October 4 2017 Maxmind GeoLite2 Country database. o Minor bugfixes (directory authority, backport from 0.3.1.5-alpha): - When a directory authority rejects a descriptor or extrainfo with a given digest, mark that digest as undownloadable, so that we do not attempt to download it again over and over. We previously tried to avoid downloading such descriptors by other means, but we didn't notice if we accidentally downloaded one anyway. This behavior became problematic in 0.2.7.2-alpha, when authorities began pinning Ed25519 keys. Fixes bug 22349; bugfix on 0.2.1.19-alpha. o Minor bugfixes (hidden service, relay, backport from 0.3.2.2-alpha): - Avoid a possible double close of a circuit by the intro point on error of sending the INTRO_ESTABLISHED cell. Fixes bug 23610; bugfix on 0.3.0.1-alpha. o Minor bugfixes (memory safety, backport from 0.3.2.3-alpha): - Clear the address when node_get_prim_orport() returns early. Fixes bug 23874; bugfix on 0.2.8.2-alpha. o Minor bugfixes (Windows service, backport from 0.3.1.6-rc): - When running as a Windows service, set the ID of the main thread correctly. Failure to do so made us fail to send log messages to the controller in 0.2.1.16-rc, slowed down controller event delivery in 0.2.7.3-rc and later, and crash with an assertion failure in 0.3.1.1-alpha. Fixes bug 23081; bugfix on 0.2.1.6-alpha. Patch and diagnosis from "Vort". Changes in version 0.3.1.8 - 2017-10-25 Tor 0.3.1.8 is the second stable release in the 0.3.1 series. It includes several bugfixes, including a bugfix for a crash issue that had affected relays under memory pressure. It also adds a new directory authority, Bastet. o Directory authority changes: - Add "Bastet" as a ninth directory authority to the default list. Closes ticket 23910. - The directory authority "Longclaw" has changed its IP address. Closes ticket 23592. o Major bugfixes (relay, crash, assertion failure, backport from 0.3.2.2-alpha): - Fix a timing-based assertion failure that could occur when the circuit out-of-memory handler freed a connection's output buffer. Fixes bug 23690; bugfix on 0.2.6.1-alpha. o Minor features (directory authorities, backport from 0.3.2.2-alpha): - Remove longclaw's IPv6 address, as it will soon change. Authority IPv6 addresses were originally added in 0.2.8.1-alpha. This leaves 3/8 directory authorities with IPv6 addresses, but there are also 52 fallback directory mirrors with IPv6 addresses. Resolves 19760. o Minor features (geoip): - Update geoip and geoip6 to the October 4 2017 Maxmind GeoLite2 Country database. o Minor bugfixes (compilation, backport from 0.3.2.2-alpha): - Fix a compilation warning when building with zstd support on 32-bit platforms. Fixes bug 23568; bugfix on 0.3.1.1-alpha. Found and fixed by Andreas Stieger. o Minor bugfixes (compression, backport from 0.3.2.2-alpha): - Handle a pathological case when decompressing Zstandard data when the output buffer size is zero. Fixes bug 23551; bugfix on 0.3.1.1-alpha. o Minor bugfixes (directory authority, backport from 0.3.2.1-alpha): - Remove the length limit on HTTP status lines that authorities can send in their replies. Fixes bug 23499; bugfix on 0.3.1.6-rc. o Minor bugfixes (hidden service, relay, backport from 0.3.2.2-alpha): - Avoid a possible double close of a circuit by the intro point on error of sending the INTRO_ESTABLISHED cell. Fixes bug 23610; bugfix on 0.3.0.1-alpha. o Minor bugfixes (memory safety, backport from 0.3.2.3-alpha): - Clear the address when node_get_prim_orport() returns early. Fixes bug 23874; bugfix on 0.2.8.2-alpha. o Minor bugfixes (unit tests, backport from 0.3.2.2-alpha): - Fix additional channelpadding unit test failures by using mocked time instead of actual time for all tests. Fixes bug 23608; bugfix on 0.3.1.1-alpha. Changes in version 0.3.2.2-alpha - 2017-09-29 Tor 0.3.2.2-alpha is the second release in the 0.3.2 series. This release fixes several minor bugs in the new scheduler and next- generation onion services; both features were newly added in the 0.3.2 series. Other fixes in this alpha include several fixes for non-fatal tracebacks which would appear in logs. With the aim to stabilise the 0.3.2 series by 15 December 2017, this alpha does not contain any substantial new features. Minor features include better testing and logging. The following comprises the complete list of changes included in 0.3.2.2-alpha: o Major bugfixes (relay, crash, assertion failure): - Fix a timing-based assertion failure that could occur when the circuit out-of-memory handler freed a connection's output buffer. Fixes bug 23690; bugfix on 0.2.6.1-alpha. o Major bugfixes (scheduler): - If a channel is put into the scheduler's pending list, then it starts closing, and then if the scheduler runs before it finishes closing, the scheduler will get stuck trying to flush its cells while the lower layers refuse to cooperate. Fix that race condition by giving the scheduler an escape method. Fixes bug 23676; bugfix on 0.3.2.1-alpha. o Minor features (build, compilation): - The "check-changes" feature is now part of the "make check" tests; we'll use it to try to prevent misformed changes files from accumulating. Closes ticket 23564. - Tor builds should now fail if there are any mismatches between the C type representing a configuration variable and the C type the data-driven parser uses to store a value there. Previously, we needed to check these by hand, which sometimes led to mistakes. Closes ticket 23643. o Minor features (directory authorities): - Remove longclaw's IPv6 address, as it will soon change. Authority IPv6 addresses were originally added in 0.2.8.1-alpha. This leaves 3/8 directory authorities with IPv6 addresses, but there are also 52 fallback directory mirrors with IPv6 addresses. Resolves 19760. o Minor features (hidden service, circuit, logging): - Improve logging of many callsite in the circuit subsystem to print the circuit identifier(s). - Log when we cleanup an intro point from a service so we know when and for what reason it happened. Closes ticket 23604. o Minor features (logging): - Log more circuit information whenever we are about to try to package a relay cell on a circuit with a nonexistent n_chan. Attempt to diagnose ticket 8185. - Improve info-level log identification of particular circuits, to help with debugging. Closes ticket 23645. o Minor features (relay): - When choosing which circuits can be expired as unused, consider circuits from clients even if those clients used regular CREATE cells to make them; and do not consider circuits from relays even if they were made with CREATE_FAST. Part of ticket 22805. o Minor features (robustness): - Change several fatal assertions when flushing buffers into non- fatal assertions, to prevent any recurrence of 23690. o Minor features (spec conformance, bridge, diagnostic): - When handling the USERADDR command on an ExtOrPort, warn when the transports provides a USERADDR with no port. In a future version, USERADDR commands of this format may be rejected. Detects problems related to ticket 23080. o Minor features (testing): - Add a unit test to make sure that our own generated platform string will be accepted by directory authorities. Closes ticket 22109. o Minor bugfixes (bootstrapping): - When warning about state file clock skew, report the correct direction for the detected skew. Fixes bug 23606; bugfix on 0.2.8.1-alpha. - Avoid an assertion failure when logging a state file clock skew very early in bootstrapping. Fixes bug 23607; bugfix on 0.3.2.1-alpha. o Minor bugfixes (build, compilation): - Fix a compilation warning when building with zstd support on 32-bit platforms. Fixes bug 23568; bugfix on 0.3.1.1-alpha. Found and fixed by Andreas Stieger. - When searching for OpenSSL, don't accept any OpenSSL library that lacks TLSv1_1_method(): Tor doesn't build with those versions. Additionally, look in /usr/local/opt/openssl, if it's present. These changes together repair the default build on OSX systems with Homebrew installed. Fixes bug 23602; bugfix on 0.2.7.2-alpha. o Minor bugfixes (compression): - Handle a pathological case when decompressing Zstandard data when the output buffer size is zero. Fixes bug 23551; bugfix on 0.3.1.1-alpha. o Minor bugfixes (documentation): - Fix manpage to not refer to the obsolete (and misspelled) UseEntryGuardsAsDirectoryGuards parameter in the description of NumDirectoryGuards. Fixes bug 23611; bugfix on 0.2.4.8-alpha. o Minor bugfixes (hidden service v3): - Don't log an assertion failure when we can't find the right information to extend to an introduction point. In rare cases, this could happen, causing a warning, even though tor would recover gracefully. Fixes bug 23159; bugfix on 0.3.2.1-alpha. - Pad RENDEZVOUS cell up to the size of the legacy cell which is much bigger so the rendezvous point can't distinguish which hidden service protocol is being used. Fixes bug 23420; bugfix on 0.3.2.1-alpha. o Minor bugfixes (hidden service, relay): - Avoid a possible double close of a circuit by the intro point on error of sending the INTRO_ESTABLISHED cell. Fixes bug 23610; bugfix on 0.3.0.1-alpha. o Minor bugfixes (logging, relay shutdown, annoyance): - When a circuit is marked for close, do not attempt to package any cells for channels on that circuit. Previously, we would detect this condition lower in the call stack, when we noticed that the circuit had no attached channel, and log an annoying message. Fixes bug 8185; bugfix on 0.2.5.4-alpha. o Minor bugfixes (scheduler): - When switching schedulers due to a consensus change, we didn't give the new scheduler a chance to react to the consensus. Fix that. Fixes bug 23537; bugfix on 0.3.2.1-alpha. - Make the KISTSchedRunInterval option a non negative value. With this, the way to disable KIST through the consensus is to set it to 0. Fixes bug 23539; bugfix on 0.3.2.1-alpha. - Only notice log the selected scheduler when we switch scheduler types. Fixes bug 23552; bugfix on 0.3.2.1-alpha. - Avoid a compilation warning on macOS in scheduler_ev_add() caused by a different tv_usec data type. Fixes bug 23575; bugfix on 0.3.2.1-alpha. - Make a hard exit if tor is unable to pick a scheduler which can happen if the user specifies a scheduler type that is not supported and not other types in Schedulers. Fixes bug 23581; bugfix on 0.3.2.1-alpha. - Properly initialize the scheduler last run time counter so it is not 0 at the first tick. Fixes bug 23696; bugfix on 0.3.2.1-alpha. o Minor bugfixes (testing): - Capture and detect several "Result does not fit" warnings in unit tests on platforms with 32-bit time_t. Fixes bug 21800; bugfix on 0.2.9.3-alpha. - Fix additional channelpadding unit test failures by using mocked time instead of actual time for all tests. Fixes bug 23608; bugfix on 0.3.1.1-alpha. - The removal of some old scheduler options caused some tests to fail on BSD systems. Assume current behavior is correct and make the tests pass again. Fixes bug 23566; bugfix on 0.3.2.1-alpha. o Code simplification and refactoring: - Remove various ways of testing circuits and connections for "clientness"; instead, favor channel_is_client(). Part of ticket 22805. o Deprecated features: - The ReachableDirAddresses and ClientPreferIPv6DirPort options are now deprecated; they do not apply to relays, and they have had no effect on clients since 0.2.8.x. Closes ticket 19704. o Documentation: - HiddenServiceVersion man page entry wasn't mentioning the now supported version 3. Fixes ticket 23580; bugfix on 0.3.2.1-alpha. - Clarify that the Address option is entirely about setting an advertised IPv4 address. Closes ticket 18891. - Clarify the manpage's use of the term "address" to clarify what kind of address is intended. Closes ticket 21405. - Document that onion service subdomains are allowed, and ignored. Closes ticket 18736. Changes in version 0.3.2.1-alpha - 2017-09-18 Tor 0.3.2.1-alpha is the first release in the 0.3.2.x series. It includes support for our next-generation ("v3") onion service protocol, and adds a new circuit scheduler for more responsive forwarding decisions from relays. There are also numerous other small features and bugfixes here. Below are the changes since Tor 0.3.1.7. o Major feature (scheduler, channel): - Tor now uses new schedulers to decide which circuits should deliver cells first, in order to improve congestion at relays. The first type is called "KIST" ("Kernel Informed Socket Transport"), and is only available on Linux-like systems: it uses feedback from the kernel to prevent the kernel's TCP buffers from growing too full. The second new scheduler type is called "KISTLite": it behaves the same as KIST, but runs on systems without kernel support for inspecting TCP implementation details. The old scheduler is still available, under the name "Vanilla". To change the default scheduler preference order, use the new "Schedulers" option. (The default preference order is "KIST,KISTLite,Vanilla".) Matt Traudt implemented KIST, based on research by Rob Jansen, John Geddes, Christ Wacek, Micah Sherr, and Paul Syverson. For more information, see the design paper at http://www.robgjansen.com/publications/kist-sec2014.pdf and the followup implementation paper at https://arxiv.org/abs/1709.01044. Closes ticket 12541. o Major features (next-generation onion services): - Tor now supports the next-generation onion services protocol for clients and services! As part of this release, the core of proposal 224 has been implemented and is available for experimentation and testing by our users. This newer version of onion services ("v3") features many improvements over the legacy system, including: a) Better crypto (replaced SHA1/DH/RSA1024 with SHA3/ed25519/curve25519) b) Improved directory protocol, leaking much less information to directory servers. c) Improved directory protocol, with smaller surface for targeted attacks. d) Better onion address security against impersonation. e) More extensible introduction/rendezvous protocol. f) A cleaner and more modular codebase. You can identify a next-generation onion address by its length: they are 56 characters long, as in "4acth47i6kxnvkewtm6q7ib2s3ufpo5sqbsnzjpbi7utijcltosqemad.onion". In the future, we will release more options and features for v3 onion services, but we first need a testing period, so that the current codebase matures and becomes more robust. Planned features include: offline keys, advanced client authorization, improved guard algorithms, and statistics. For full details, see proposal 224. Legacy ("v2") onion services will still work for the foreseeable future, and will remain the default until this new codebase gets tested and hardened. Service operators who want to experiment with the new system can use the 'HiddenServiceVersion 3' torrc directive along with the regular onion service configuration options. We will publish a blog post about this new feature soon! Enjoy! o Major bugfixes (usability, control port): - Report trusted clock skew indications as bootstrap errors, so controllers can more easily alert users when their clocks are wrong. Fixes bug 23506; bugfix on 0.1.2.6-alpha. o Minor features (bug detection): - Log a warning message with a stack trace for any attempt to call get_options() during option validation. This pattern has caused subtle bugs in the past. Closes ticket 22281. o Minor features (client): - You can now use Tor as a tunneled HTTP proxy: use the new HTTPTunnelPort option to open a port that accepts HTTP CONNECT requests. Closes ticket 22407. - Add an extra check to make sure that we always use the newer guard selection code for picking our guards. Closes ticket 22779. - When downloading (micro)descriptors, don't split the list into multiple requests unless we want at least 32 descriptors. Previously, we split at 4, not 32, which led to significant overhead in HTTP request size and degradation in compression performance. Closes ticket 23220. o Minor features (command line): - Add a new commandline option, --key-expiration, which prints when the current signing key is going to expire. Implements ticket 17639; patch by Isis Lovecruft. o Minor features (control port): - If an application tries to use the control port as an HTTP proxy, respond with a meaningful "This is the Tor control port" message, and log the event. Closes ticket 1667. Patch from Ravi Chandra Padmala. - Provide better error message for GETINFO desc/(id|name) when not fetching router descriptors. Closes ticket 5847. Patch by Kevin Butler. - Add GETINFO "{desc,md}/download-enabled", to inform the controller whether Tor will try to download router descriptors and microdescriptors respectively. Closes ticket 22684. - Added new GETINFO targets "ip-to-country/{ipv4,ipv6}-available", so controllers can tell whether the geoip databases are loaded. Closes ticket 23237. - Adds a timestamp field to the CIRC_BW and STREAM_BW bandwidth events. Closes ticket 19254. Patch by "DonnchaC". o Minor features (development support): - Developers can now generate a call-graph for Tor using the "calltool" python program, which post-processes object dumps. It should work okay on many Linux and OSX platforms, and might work elsewhere too. To run it, install calltool from https://gitweb.torproject.org/user/nickm/calltool.git and run "make callgraph". Closes ticket 19307. o Minor features (ed25519): - Add validation function to checks for torsion components in ed25519 public keys, used by prop224 client-side code. Closes ticket 22006. Math help by Ian Goldberg. o Minor features (exit relay, DNS): - Improve the clarity and safety of the log message from evdns when receiving an apparently spoofed DNS reply. Closes ticket 3056. o Minor features (integration, hardening): - Add a new NoExec option to prevent Tor from running other programs. When this option is set to 1, Tor will never try to run another program, regardless of the settings of PortForwardingHelper, ClientTransportPlugin, or ServerTransportPlugin. Once NoExec is set, it cannot be disabled without restarting Tor. Closes ticket 22976. o Minor features (logging): - Improve the warning message for specifying a relay by nickname. The previous message implied that nickname registration was still part of the Tor network design, which it isn't. Closes ticket 20488. - If the sandbox filter fails to load, suggest to the user that their kernel might not support seccomp2. Closes ticket 23090. o Minor features (portability): - Check at configure time whether uint8_t is the same type as unsigned char. Lots of existing code already makes this assumption, and there could be strict aliasing issues if the assumption is violated. Closes ticket 22410. o Minor features (relay, configuration): - Reject attempts to use relative file paths when RunAsDaemon is set. Previously, Tor would accept these, but the directory- changing step of RunAsDaemon would give strange and/or confusing results. Closes ticket 22731. o Minor features (startup, safety): - When configured to write a PID file, Tor now exits if it is unable to do so. Previously, it would warn and continue. Closes ticket 20119. o Minor features (static analysis): - The BUG() macro has been changed slightly so that Coverity no longer complains about dead code if the bug is impossible. Closes ticket 23054. o Minor features (testing): - The default chutney network tests now include tests for the v3 hidden service design. Make sure you have the latest version of chutney if you want to run these. Closes ticket 22437. - Add a unit test to verify that we can parse a hardcoded v2 hidden service descriptor. Closes ticket 15554. o Minor bugfixes (certificate handling): - Fix a time handling bug in Tor certificates set to expire after the year 2106. Fixes bug 23055; bugfix on 0.3.0.1-alpha. Found by Coverity as CID 1415728. o Minor bugfixes (client, usability): - Refrain from needlessly rejecting SOCKS5-with-hostnames and SOCKS4a requests that contain IP address strings, even when SafeSocks in enabled, as this prevents user from connecting to known IP addresses without relying on DNS for resolving. SafeSocks still rejects SOCKS connections that connect to IP addresses when those addresses are _not_ encoded as hostnames. Fixes bug 22461; bugfix on Tor 0.2.6.2-alpha. o Minor bugfixes (code correctness): - Call htons() in extend_cell_format() for encoding a 16-bit value. Previously we used ntohs(), which happens to behave the same on all the platforms we support, but which isn't really correct. Fixes bug 23106; bugfix on 0.2.4.8-alpha. - For defense-in-depth, make the controller's write_escaped_data() function robust to extremely long inputs. Fixes bug 19281; bugfix on 0.1.1.1-alpha. Reported by Guido Vranken. o Minor bugfixes (compilation): - Fix unused-variable warnings in donna's Curve25519 SSE2 code. Fixes bug 22895; bugfix on 0.2.7.2-alpha. o Minor bugfixes (consensus expiry): - Check for adequate directory information correctly. Previously, Tor would reconsider whether it had sufficient directory information every 2 minutes. Fixes bug 23091; bugfix on 0.2.0.19-alpha. o Minor bugfixes (directory protocol): - Directory servers now include a "Date:" http header for response codes other than 200. Clients starting with a skewed clock and a recent consensus were getting "304 Not modified" responses from directory authorities, so without the Date header, the client would never hear about a wrong clock. Fixes bug 23499; bugfix on 0.0.8rc1. - Make clients wait for 6 seconds before trying to download a consensus from an authority. Fixes bug 17750; bugfix on 0.2.8.1-alpha. o Minor bugfixes (DoS-resistance): - If future code asks if there are any running bridges, without checking if bridges are enabled, log a BUG warning rather than crashing. Fixes bug 23524; bugfix on 0.3.0.1-alpha. o Minor bugfixes (format strictness): - Restrict several data formats to decimal. Previously, the BuildTimeHistogram entries in the state file, the "bw=" entries in the bandwidth authority file, and the process IDs passed to the __OwningControllerProcess option could all be specified in hex or octal as well as in decimal. This was not an intentional feature. Fixes bug 22802; bugfixes on 0.2.2.1-alpha, 0.2.2.2-alpha, and 0.2.2.28-beta. o Minor bugfixes (heartbeat): - If we fail to write a heartbeat message, schedule a retry for the minimum heartbeat interval number of seconds in the future. Fixes bug 19476; bugfix on 0.2.3.1-alpha. o Minor bugfixes (linux seccomp2 sandbox, logging): - Fix some messages on unexpected errors from the seccomp2 library. Fixes bug 22750; bugfix on 0.2.5.1-alpha. Patch from "cypherpunks". o Minor bugfixes (logging): - Remove duplicate log messages regarding opening non-local SocksPorts upon parsing config and opening listeners at startup. Fixes bug 4019; bugfix on 0.2.3.3-alpha. - Use a more comprehensible log message when telling the user they've excluded every running exit node. Fixes bug 7890; bugfix on 0.2.2.25-alpha. - When logging the number of descriptors we intend to download per directory request, do not log a number higher than then the number of descriptors we're fetching in total. Fixes bug 19648; bugfix on 0.1.1.8-alpha. - When warning about a directory owned by the wrong user, log the actual name of the user owning the directory. Previously, we'd log the name of the process owner twice. Fixes bug 23487; bugfix on 0.2.9.1-alpha. - The tor specification says hop counts are 1-based, so fix two log messages that mistakenly logged 0-based hop counts. Fixes bug 18982; bugfix on 0.2.6.2-alpha and 0.2.4.5-alpha. Patch by teor. Credit to Xiaofan Li for reporting this issue. o Minor bugfixes (portability): - Stop using the PATH_MAX variable, which is not defined on GNU Hurd. Fixes bug 23098; bugfix on 0.3.1.1-alpha. o Minor bugfixes (relay): - When uploading our descriptor for the first time after startup, report the reason for uploading as "Tor just started" rather than leaving it blank. Fixes bug 22885; bugfix on 0.2.3.4-alpha. - Avoid unnecessary calls to directory_fetches_from_authorities() on relays, to prevent spurious address resolutions and descriptor rebuilds. This is a mitigation for bug 21789. Fixes bug 23470; bugfix on in 0.2.8.1-alpha. o Minor bugfixes (tests): - Fix a broken unit test for the OutboundAddress option: the parsing function was never returning an error on failure. Fixes bug 23366; bugfix on 0.3.0.3-alpha. - Fix a signed-integer overflow in the unit tests for dir/download_status_random_backoff, which was untriggered until we fixed bug 17750. Fixes bug 22924; bugfix on 0.2.9.1-alpha. o Minor bugfixes (usability, control port): - Stop making an unnecessary routerlist check in NETINFO clock skew detection; this was preventing clients from reporting NETINFO clock skew to controllers. Fixes bug 23532; bugfix on 0.2.4.4-alpha. o Code simplification and refactoring: - Extract the code for handling newly-open channels into a separate function from the general code to handle channel state transitions. This change simplifies our callgraph, reducing the size of the largest strongly connected component by roughly a factor of two. Closes ticket 22608. - Remove dead code for largely unused statistics on the number of times we've attempted various public key operations. Fixes bug 19871; bugfix on 0.1.2.4-alpha. Fix by Isis Lovecruft. - Remove several now-obsolete functions for asking about old variants directory authority status. Closes ticket 22311; patch from "huyvq". - Remove some of the code that once supported "Named" and "Unnamed" routers. Authorities no longer vote for these flags. Closes ticket 22215. - Rename the obsolete malleable hybrid_encrypt functions used in TAP and old hidden services, to indicate that they aren't suitable for new protocols or formats. Closes ticket 23026. - Replace our STRUCT_OFFSET() macro with offsetof(). Closes ticket 22521. Patch from Neel Chauhan. - Split the enormous circuit_send_next_onion_skin() function into multiple subfunctions. Closes ticket 22804. - Split the portions of the buffer.c module that handle particular protocols into separate modules. Part of ticket 23149. - Use our test macros more consistently, to produce more useful error messages when our unit tests fail. Add coccinelle patches to allow us to re-check for test macro uses. Closes ticket 22497. o Deprecated features: - Deprecate HTTPProxy/HTTPProxyAuthenticator config options. They only applies to direct unencrypted HTTP connections to your directory server, which your Tor probably isn't using. Closes ticket 20575. o Documentation: - Clarify in the manual that "Sandbox 1" is only supported on Linux kernels. Closes ticket 22677. - Document all values of PublishServerDescriptor in the manpage. Closes ticket 15645. - Improve the documentation for the directory port part of the DirAuthority line. Closes ticket 20152. - Restore documentation for the authorities' "approved-routers" file. Closes ticket 21148. o Removed features: - The AllowDotExit option has been removed as unsafe. It has been deprecated since 0.2.9.2-alpha. Closes ticket 23426. - The ClientDNSRejectInternalAddresses flag can no longer be set on non-testing networks. It has been deprecated since 0.2.9.2-alpha. Closes ticket 21031. - The controller API no longer includes an AUTHDIR_NEWDESCS event: nobody was using it any longer. Closes ticket 22377. Changes in version 0.2.8.15 - 2017-09-18 Tor 0.2.8.15 backports a collection of bugfixes from later Tor series. Most significantly, it includes a fix for TROVE-2017-008, a security bug that affects hidden services running with the SafeLogging option disabled. For more information, see https://trac.torproject.org/projects/tor/ticket/23490 Note that Tor 0.2.8.x will no longer be supported after 1 Jan 2018. We suggest that you upgrade to the latest stable release if possible. If you can't, we recommend that you upgrade at least to 0.2.9, which will be supported until 2020. o Major bugfixes (openbsd, denial-of-service, backport from 0.3.1.5-alpha): - Avoid an assertion failure bug affecting our implementation of inet_pton(AF_INET6) on certain OpenBSD systems whose strtol() handling of "0xx" differs from what we had expected. Fixes bug 22789; bugfix on 0.2.3.8-alpha. Also tracked as TROVE-2017-007. o Minor features: - Update geoip and geoip6 to the September 6 2017 Maxmind GeoLite2 Country database. o Minor bugfixes (compilation, mingw, backport from 0.3.1.1-alpha): - Backport a fix for an "unused variable" warning that appeared in some versions of mingw. Fixes bug 22838; bugfix on 0.2.8.1-alpha. o Minor bugfixes (defensive programming, undefined behavior, backport from 0.3.1.4-alpha): - Fix a memset() off the end of an array when packing cells. This bug should be harmless in practice, since the corrupted bytes are still in the same structure, and are always padding bytes, ignored, or immediately overwritten, depending on compiler behavior. Nevertheless, because the memset()'s purpose is to make sure that any other cell-handling bugs can't expose bytes to the network, we need to fix it. Fixes bug 22737; bugfix on 0.2.4.11-alpha. Fixes CID 1401591. o Build features (backport from 0.3.1.5-alpha): - Tor's repository now includes a Travis Continuous Integration (CI) configuration file (.travis.yml). This is meant to help new developers and contributors who fork Tor to a Github repository be better able to test their changes, and understand what we expect to pass. To use this new build feature, you must fork Tor to your Github account, then go into the "Integrations" menu in the repository settings for your fork and enable Travis, then push your changes. Closes ticket 22636. Changes in version 0.2.9.12 - 2017-09-18 Tor 0.2.9.12 backports a collection of bugfixes from later Tor series. Most significantly, it includes a fix for TROVE-2017-008, a security bug that affects hidden services running with the SafeLogging option disabled. For more information, see https://trac.torproject.org/projects/tor/ticket/23490 o Major features (security, backport from 0.3.0.2-alpha): - Change the algorithm used to decide DNS TTLs on client and server side, to better resist DNS-based correlation attacks like the DefecTor attack of Greschbach, Pulls, Roberts, Winter, and Feamster. Now relays only return one of two possible DNS TTL values, and clients are willing to believe DNS TTL values up to 3 hours long. Closes ticket 19769. o Major bugfixes (crash, directory connections, backport from 0.3.0.5-rc): - Fix a rare crash when sending a begin cell on a circuit whose linked directory connection had already been closed. Fixes bug 21576; bugfix on 0.2.9.3-alpha. Reported by Alec Muffett. o Major bugfixes (DNS, backport from 0.3.0.2-alpha): - Fix a bug that prevented exit nodes from caching DNS records for more than 60 seconds. Fixes bug 19025; bugfix on 0.2.4.7-alpha. o Major bugfixes (linux TPROXY support, backport from 0.3.1.1-alpha): - Fix a typo that had prevented TPROXY-based transparent proxying from working under Linux. Fixes bug 18100; bugfix on 0.2.6.3-alpha. Patch from "d4fq0fQAgoJ". o Major bugfixes (openbsd, denial-of-service, backport from 0.3.1.5-alpha): - Avoid an assertion failure bug affecting our implementation of inet_pton(AF_INET6) on certain OpenBSD systems whose strtol() handling of "0xx" differs from what we had expected. Fixes bug 22789; bugfix on 0.2.3.8-alpha. Also tracked as TROVE-2017-007. o Minor features (code style, backport from 0.3.1.3-alpha): - Add "Falls through" comments to our codebase, in order to silence GCC 7's -Wimplicit-fallthrough warnings. Patch from Andreas Stieger. Closes ticket 22446. o Minor features (geoip): - Update geoip and geoip6 to the September 6 2017 Maxmind GeoLite2 Country database. o Minor bugfixes (bandwidth accounting, backport from 0.3.1.1-alpha): - Roll over monthly accounting at the configured hour and minute, rather than always at 00:00. Fixes bug 22245; bugfix on 0.0.9rc1. Found by Andrey Karpov with PVS-Studio. o Minor bugfixes (compilation, backport from 0.3.1.5-alpha): - Suppress -Wdouble-promotion warnings with clang 4.0. Fixes bug 22915; bugfix on 0.2.8.1-alpha. - Fix warnings when building with libscrypt and openssl scrypt support on Clang. Fixes bug 22916; bugfix on 0.2.7.2-alpha. - When building with certain versions the mingw C header files, avoid float-conversion warnings when calling the C functions isfinite(), isnan(), and signbit(). Fixes bug 22801; bugfix on 0.2.8.1-alpha. o Minor bugfixes (compilation, backport from 0.3.1.7): - Avoid compiler warnings in the unit tests for running tor_sscanf() with wide string outputs. Fixes bug 15582; bugfix on 0.2.6.2-alpha. o Minor bugfixes (compilation, mingw, backport from 0.3.1.1-alpha): - Backport a fix for an "unused variable" warning that appeared in some versions of mingw. Fixes bug 22838; bugfix on 0.2.8.1-alpha. o Minor bugfixes (controller, backport from 0.3.1.7): - Do not crash when receiving a HSPOST command with an empty body. Fixes part of bug 22644; bugfix on 0.2.7.1-alpha. - Do not crash when receiving a POSTDESCRIPTOR command with an empty body. Fixes part of bug 22644; bugfix on 0.2.0.1-alpha. o Minor bugfixes (coverity build support, backport from 0.3.1.5-alpha): - Avoid Coverity build warnings related to our BUG() macro. By default, Coverity treats BUG() as the Linux kernel does: an instant abort(). We need to override that so our BUG() macro doesn't prevent Coverity from analyzing functions that use it. Fixes bug 23030; bugfix on 0.2.9.1-alpha. o Minor bugfixes (defensive programming, undefined behavior, backport from 0.3.1.4-alpha): - Fix a memset() off the end of an array when packing cells. This bug should be harmless in practice, since the corrupted bytes are still in the same structure, and are always padding bytes, ignored, or immediately overwritten, depending on compiler behavior. Nevertheless, because the memset()'s purpose is to make sure that any other cell-handling bugs can't expose bytes to the network, we need to fix it. Fixes bug 22737; bugfix on 0.2.4.11-alpha. Fixes CID 1401591. o Minor bugfixes (file limits, osx, backport from 0.3.1.5-alpha): - When setting the maximum number of connections allowed by the OS, always allow some extra file descriptors for other files. Fixes bug 22797; bugfix on 0.2.0.10-alpha. o Minor bugfixes (linux seccomp2 sandbox, backport from 0.3.1.5-alpha): - Avoid a sandbox failure when trying to re-bind to a socket and mark it as IPv6-only. Fixes bug 20247; bugfix on 0.2.5.1-alpha. o Minor bugfixes (linux seccomp2 sandbox, backport from 0.3.1.4-alpha): - Permit the fchmod system call, to avoid crashing on startup when starting with the seccomp2 sandbox and an unexpected set of permissions on the data directory or its contents. Fixes bug 22516; bugfix on 0.2.5.4-alpha. o Minor bugfixes (relay, backport from 0.3.0.5-rc): - Avoid a double-marked-circuit warning that could happen when we receive DESTROY cells under heavy load. Fixes bug 20059; bugfix on 0.1.0.1-rc. o Minor bugfixes (voting consistency, backport from 0.3.1.1-alpha): - Reject version numbers with non-numeric prefixes (such as +, -, or whitespace). Disallowing whitespace prevents differential version parsing between POSIX-based and Windows platforms. Fixes bug 21507 and part of 21508; bugfix on 0.0.8pre1. o Build features (backport from 0.3.1.5-alpha): - Tor's repository now includes a Travis Continuous Integration (CI) configuration file (.travis.yml). This is meant to help new developers and contributors who fork Tor to a Github repository be better able to test their changes, and understand what we expect to pass. To use this new build feature, you must fork Tor to your Github account, then go into the "Integrations" menu in the repository settings for your fork and enable Travis, then push your changes. Closes ticket 22636. Changes in version 0.3.0.11 - 2017-09-18 Tor 0.3.0.11 backports a collection of bugfixes from Tor the 0.3.1 series. Most significantly, it includes a fix for TROVE-2017-008, a security bug that affects hidden services running with the SafeLogging option disabled. For more information, see https://trac.torproject.org/projects/tor/ticket/23490 o Minor features (code style, backport from 0.3.1.7): - Add "Falls through" comments to our codebase, in order to silence GCC 7's -Wimplicit-fallthrough warnings. Patch from Andreas Stieger. Closes ticket 22446. o Minor features: - Update geoip and geoip6 to the September 6 2017 Maxmind GeoLite2 Country database. o Minor bugfixes (compilation, backport from 0.3.1.7): - Avoid compiler warnings in the unit tests for calling tor_sscanf() with wide string outputs. Fixes bug 15582; bugfix on 0.2.6.2-alpha. o Minor bugfixes (controller, backport from 0.3.1.7): - Do not crash when receiving a HSPOST command with an empty body. Fixes part of bug 22644; bugfix on 0.2.7.1-alpha. - Do not crash when receiving a POSTDESCRIPTOR command with an empty body. Fixes part of bug 22644; bugfix on 0.2.0.1-alpha. o Minor bugfixes (file limits, osx, backport from 0.3.1.5-alpha): - When setting the maximum number of connections allowed by the OS, always allow some extra file descriptors for other files. Fixes bug 22797; bugfix on 0.2.0.10-alpha. o Minor bugfixes (logging, relay, backport from 0.3.1.6-rc): - Remove a forgotten debugging message when an introduction point successfully establishes a hidden service prop224 circuit with a client. - Change three other log_warn() for an introduction point to protocol warnings, because they can be failure from the network and are not relevant to the operator. Fixes bug 23078; bugfix on 0.3.0.1-alpha and 0.3.0.2-alpha. Changes in version 0.3.1.7 - 2017-09-18 Tor 0.3.1.7 is the first stable release in the 0.3.1 series. With the 0.3.1 series, Tor now serves and downloads directory information in more compact formats, to save on bandwidth overhead. It also contains a new padding system to resist netflow-based traffic analysis, and experimental support for building parts of Tor in Rust (though no parts of Tor are in Rust yet). There are also numerous small features, bugfixes on earlier release series, and groundwork for the hidden services revamp of 0.3.2. This release also includes a fix for TROVE-2017-008, a security bug that affects hidden services running with the SafeLogging option disabled. For more information, see https://trac.torproject.org/projects/tor/ticket/23490 Per our stable release policy, we plan to support each stable release series for at least the next nine months, or for three months after the first stable release of the next series: whichever is longer. If you need a release with long-term support, we recommend that you stay with the 0.2.9 series. Below is a list of the changes since 0.3.1.6-rc. For a list of all changes since 0.3.0, see the ReleaseNotes file. o Major bugfixes (security, hidden services, loggging): - Fix a bug where we could log uninitialized stack when a certain hidden service error occurred while SafeLogging was disabled. Fixes bug #23490; bugfix on 0.2.7.2-alpha. This is also tracked as TROVE-2017-008 and CVE-2017-0380. o Minor features (defensive programming): - Create a pair of consensus parameters, nf_pad_tor2web and nf_pad_single_onion, to disable netflow padding in the consensus for non-anonymous connections in case the overhead is high. Closes ticket 17857. o Minor features (diagnostic): - Add a stack trace to the bug warnings that can be logged when trying to send an outgoing relay cell with n_chan == 0. Diagnostic attempt for bug 23105. o Minor features (geoip): - Update geoip and geoip6 to the September 6 2017 Maxmind GeoLite2 Country database. o Minor bugfixes (compilation): - Avoid compiler warnings in the unit tests for calling tor_sscanf() with wide string outputs. Fixes bug 15582; bugfix on 0.2.6.2-alpha. o Minor bugfixes (controller): - Do not crash when receiving a HSPOST command with an empty body. Fixes part of bug 22644; bugfix on 0.2.7.1-alpha. - Do not crash when receiving a POSTDESCRIPTOR command with an empty body. Fixes part of bug 22644; bugfix on 0.2.0.1-alpha. o Minor bugfixes (relay): - Inform the geoip and rephist modules about all requests, even on relays that are only fetching microdescriptors. Fixes a bug related to 21585; bugfix on 0.3.0.1-alpha. o Minor bugfixes (unit tests): - Fix a channelpadding unit test failure on slow systems by using mocked time instead of actual time. Fixes bug 23077; bugfix on 0.3.1.1-alpha. Changes in version 0.3.1.6-rc - 2017-09-05 Tor 0.3.1.6-rc fixes a few small bugs and annoyances in the 0.3.1 release series, including a bug that produced weird behavior on Windows directory caches. This is the first release candidate in the Tor 0.3.1 series. If we find no new bugs or regressions here, the first stable 0.3.1 release will be nearly identical to it. o Major bugfixes (windows, directory cache): - On Windows, do not try to delete cached consensus documents and diffs before they are unmapped from memory--Windows won't allow that. Instead, allow the consensus cache directory to grow larger, to hold files that might need to stay around longer. Fixes bug 22752; bugfix on 0.3.1.1-alpha. o Minor features (directory authority): - Improve the message that authorities report to relays that present RSA/Ed25519 keypairs that conflict with previously pinned keys. Closes ticket 22348. o Minor features (geoip): - Update geoip and geoip6 to the August 3 2017 Maxmind GeoLite2 Country database. o Minor features (testing): - Add more tests for compression backend initialization. Closes ticket 22286. o Minor bugfixes (directory cache): - Fix a memory leak when recovering space in the consensus cache. Fixes bug 23139; bugfix on 0.3.1.1-alpha. o Minor bugfixes (hidden service): - Increase the number of circuits that a service is allowed to open over a specific period of time. The value was lower than it should be (8 vs 12) in the normal case of 3 introduction points. Fixes bug 22159; bugfix on 0.3.0.5-rc. - Fix a BUG warning during HSv3 descriptor decoding that could be cause by a specially crafted descriptor. Fixes bug 23233; bugfix on 0.3.0.1-alpha. Bug found by "haxxpop". - Rate-limit the log messages if we exceed the maximum number of allowed intro circuits. Fixes bug 22159; bugfix on 0.3.1.1-alpha. o Minor bugfixes (logging, relay): - Remove a forgotten debugging message when an introduction point successfully establishes a hidden service prop224 circuit with a client. - Change three other log_warn() for an introduction point to protocol warnings, because they can be failure from the network and are not relevant to the operator. Fixes bug 23078; bugfix on 0.3.0.1-alpha and 0.3.0.2-alpha. o Minor bugfixes (relay): - When a relay is not running as a directory cache, it will no longer generate compressed consensuses and consensus diff information. Previously, this was a waste of disk and CPU. Fixes bug 23275; bugfix on 0.3.1.1-alpha. o Minor bugfixes (robustness, error handling): - Improve our handling of the cases where OpenSSL encounters a memory error while encoding keys and certificates. We haven't observed these errors in the wild, but if they do happen, we now detect and respond better. Fixes bug 19418; bugfix on all versions of Tor. Reported by Guido Vranken. o Minor bugfixes (stability): - Avoid crashing on a double-free when unable to load or process an included file. Fixes bug 23155; bugfix on 0.3.1.1-alpha. Found with the clang static analyzer. o Minor bugfixes (testing): - Fix an undersized buffer in test-memwipe.c. Fixes bug 23291; bugfix on 0.2.7.2-alpha. Found and patched by Ties Stuij. - Port the hs_ntor handshake test to work correctly with recent versions of the pysha3 module. Fixes bug 23071; bugfix on 0.3.1.1-alpha. o Minor bugfixes (Windows service): - When running as a Windows service, set the ID of the main thread correctly. Failure to do so made us fail to send log messages to the controller in 0.2.1.16-rc, slowed down controller event delivery in 0.2.7.3-rc and later, and crash with an assertion failure in 0.3.1.1-alpha. Fixes bug 23081; bugfix on 0.2.1.6-alpha. Patch and diagnosis from "Vort". Changes in version 0.3.0.10 - 2017-08-02 Tor 0.3.0.10 backports a collection of small-to-medium bugfixes from the current Tor alpha series. OpenBSD users and TPROXY users should upgrade; others are probably okay sticking with 0.3.0.9. o Major features (build system, continuous integration, backport from 0.3.1.5-alpha): - Tor's repository now includes a Travis Continuous Integration (CI) configuration file (.travis.yml). This is meant to help new developers and contributors who fork Tor to a Github repository be better able to test their changes, and understand what we expect to pass. To use this new build feature, you must fork Tor to your Github account, then go into the "Integrations" menu in the repository settings for your fork and enable Travis, then push your changes. Closes ticket 22636. o Major bugfixes (linux TPROXY support, backport from 0.3.1.1-alpha): - Fix a typo that had prevented TPROXY-based transparent proxying from working under Linux. Fixes bug 18100; bugfix on 0.2.6.3-alpha. Patch from "d4fq0fQAgoJ". o Major bugfixes (openbsd, denial-of-service, backport from 0.3.1.5-alpha): - Avoid an assertion failure bug affecting our implementation of inet_pton(AF_INET6) on certain OpenBSD systems whose strtol() handling of "0xbar" differs from what we had expected. Fixes bug 22789; bugfix on 0.2.3.8-alpha. Also tracked as TROVE-2017-007. o Minor features (backport from 0.3.1.5-alpha): - Update geoip and geoip6 to the July 4 2017 Maxmind GeoLite2 Country database. o Minor bugfixes (bandwidth accounting, backport from 0.3.1.2-alpha): - Roll over monthly accounting at the configured hour and minute, rather than always at 00:00. Fixes bug 22245; bugfix on 0.0.9rc1. Found by Andrey Karpov with PVS-Studio. o Minor bugfixes (compilation warnings, backport from 0.3.1.5-alpha): - Suppress -Wdouble-promotion warnings with clang 4.0. Fixes bug 22915; bugfix on 0.2.8.1-alpha. - Fix warnings when building with libscrypt and openssl scrypt support on Clang. Fixes bug 22916; bugfix on 0.2.7.2-alpha. - When building with certain versions of the mingw C header files, avoid float-conversion warnings when calling the C functions isfinite(), isnan(), and signbit(). Fixes bug 22801; bugfix on 0.2.8.1-alpha. o Minor bugfixes (compilation, mingw, backport from 0.3.1.1-alpha): - Backport a fix for an "unused variable" warning that appeared in some versions of mingw. Fixes bug 22838; bugfix on 0.2.8.1-alpha. o Minor bugfixes (coverity build support, backport from 0.3.1.5-alpha): - Avoid Coverity build warnings related to our BUG() macro. By default, Coverity treats BUG() as the Linux kernel does: an instant abort(). We need to override that so our BUG() macro doesn't prevent Coverity from analyzing functions that use it. Fixes bug 23030; bugfix on 0.2.9.1-alpha. o Minor bugfixes (directory authority, backport from 0.3.1.1-alpha): - When rejecting a router descriptor for running an obsolete version of Tor without ntor support, warn about the obsolete tor version, not the missing ntor key. Fixes bug 20270; bugfix on 0.2.9.3-alpha. o Minor bugfixes (linux seccomp2 sandbox, backport from 0.3.1.5-alpha): - Avoid a sandbox failure when trying to re-bind to a socket and mark it as IPv6-only. Fixes bug 20247; bugfix on 0.2.5.1-alpha. o Minor bugfixes (unit tests, backport from 0.3.1.5-alpha) - Fix a memory leak in the link-handshake/certs_ok_ed25519 test. Fixes bug 22803; bugfix on 0.3.0.1-alpha. Changes in version 0.3.1.5-alpha - 2017-08-01 Tor 0.3.1.5-alpha improves the performance of consensus diff calculation, fixes a crash bug on older versions of OpenBSD, and fixes several other bugs. If no serious bugs are found in this version, the next version will be a release candidate. This release also marks the end of support for the Tor 0.2.4.x, 0.2.6.x, and 0.2.7.x release series. Those releases will receive no further bug or security fixes. Anyone still running or distributing one of those versions should upgrade. o Major features (build system, continuous integration): - Tor's repository now includes a Travis Continuous Integration (CI) configuration file (.travis.yml). This is meant to help new developers and contributors who fork Tor to a Github repository be better able to test their changes, and understand what we expect to pass. To use this new build feature, you must fork Tor to your Github account, then go into the "Integrations" menu in the repository settings for your fork and enable Travis, then push your changes. Closes ticket 22636. o Major bugfixes (openbsd, denial-of-service): - Avoid an assertion failure bug affecting our implementation of inet_pton(AF_INET6) on certain OpenBSD systems whose strtol() handling of "0xbar" differs from what we had expected. Fixes bug 22789; bugfix on 0.2.3.8-alpha. Also tracked as TROVE-2017-007. o Major bugfixes (relay, performance): - Perform circuit handshake operations at a higher priority than we use for consensus diff creation and compression. This should prevent circuits from starving when a relay or bridge receives a new consensus, especially on lower-powered machines. Fixes bug 22883; bugfix on 0.3.1.1-alpha. o Minor features (bridge authority): - Add "fingerprint" lines to the networkstatus-bridges file produced by bridge authorities. Closes ticket 22207. o Minor features (directory cache, consensus diff): - Add a new MaxConsensusAgeForDiffs option to allow directory cache operators with low-resource environments to adjust the number of consensuses they'll store and generate diffs from. Most cache operators should leave it unchanged. Helps to work around bug 22883. o Minor features (geoip): - Update geoip and geoip6 to the July 4 2017 Maxmind GeoLite2 Country database. o Minor features (relay, performance): - Always start relays with at least two worker threads, to prevent priority inversion on slow tasks. Part of the fix for bug 22883. - Allow background work to be queued with different priorities, so that a big pile of slow low-priority jobs will not starve out higher priority jobs. This lays the groundwork for a fix for bug 22883. o Minor bugfixes (build system, rust): - Fix a problem where Rust toolchains were not being found when building without --enable-cargo-online-mode, due to setting the $HOME environment variable instead of $CARGO_HOME. Fixes bug 22830; bugfix on 0.3.1.1-alpha. Fix by Chelsea Komlo. o Minor bugfixes (compatibility, zstd): - Write zstd epilogues correctly when the epilogue requires reallocation of the output buffer, even with zstd 1.3.0. (Previously, we worked on 1.2.0 and failed with 1.3.0). Fixes bug 22927; bugfix on 0.3.1.1-alpha. o Minor bugfixes (compilation warnings): - Suppress -Wdouble-promotion warnings with clang 4.0. Fixes bug 22915; bugfix on 0.2.8.1-alpha. - Fix warnings when building with libscrypt and openssl scrypt support on Clang. Fixes bug 22916; bugfix on 0.2.7.2-alpha. - Compile correctly when both openssl 1.1.0 and libscrypt are detected. Previously this would cause an error. Fixes bug 22892; bugfix on 0.3.1.1-alpha. - When building with certain versions of the mingw C header files, avoid float-conversion warnings when calling the C functions isfinite(), isnan(), and signbit(). Fixes bug 22801; bugfix on 0.2.8.1-alpha. o Minor bugfixes (coverity build support): - Avoid Coverity build warnings related to our BUG() macro. By default, Coverity treats BUG() as the Linux kernel does: an instant abort(). We need to override that so our BUG() macro doesn't prevent Coverity from analyzing functions that use it. Fixes bug 23030; bugfix on 0.2.9.1-alpha. o Minor bugfixes (directory authority): - When a directory authority rejects a descriptor or extrainfo with a given digest, mark that digest as undownloadable, so that we do not attempt to download it again over and over. We previously tried to avoid downloading such descriptors by other means, but we didn't notice if we accidentally downloaded one anyway. This behavior became problematic in 0.2.7.2-alpha, when authorities began pinning Ed25519 keys. Fixes bug 22349; bugfix on 0.2.1.19-alpha. o Minor bugfixes (error reporting, windows): - When formatting Windows error messages, use the English format to avoid codepage issues. Fixes bug 22520; bugfix on 0.1.2.8-alpha. Patch from "Vort". o Minor bugfixes (file limits, osx): - When setting the maximum number of connections allowed by the OS, always allow some extra file descriptors for other files. Fixes bug 22797; bugfix on 0.2.0.10-alpha. o Minor bugfixes (linux seccomp2 sandbox): - Avoid a sandbox failure when trying to re-bind to a socket and mark it as IPv6-only. Fixes bug 20247; bugfix on 0.2.5.1-alpha. o Minor bugfixes (memory leaks): - Fix a small memory leak when validating a configuration that uses two or more AF_UNIX sockets for the same port type. Fixes bug 23053; bugfix on 0.2.6.3-alpha. This is CID 1415725. o Minor bugfixes (unit tests): - test_consdiff_base64cmp would fail on OS X because while OS X follows the standard of (less than zero/zero/greater than zero), it doesn't follow the convention of (-1/0/+1). Make the test comply with the standard. Fixes bug 22870; bugfix on 0.3.1.1-alpha. - Fix a memory leak in the link-handshake/certs_ok_ed25519 test. Fixes bug 22803; bugfix on 0.3.0.1-alpha. Changes in version 0.3.1.4-alpha - 2017-06-29 Tor 0.3.1.4-alpha fixes a path selection bug that would allow a client to use a guard that was in the same network family as a chosen exit relay. This is a security regression; all clients running earlier versions of 0.3.0.x or 0.3.1.x should upgrade to 0.3.0.9 or 0.3.1.4-alpha. This release also fixes several other bugs introduced in 0.3.0.x and 0.3.1.x, including others that can affect bandwidth usage and correctness. o New dependencies: - To build with zstd and lzma support, Tor now requires the pkg-config tool at build time. (This requirement was new in 0.3.1.1-alpha, but was not noted at the time. Noting it here to close ticket 22623.) o Major bugfixes (path selection, security): - When choosing which guard to use for a circuit, avoid the exit's family along with the exit itself. Previously, the new guard selection logic avoided the exit, but did not consider its family. Fixes bug 22753; bugfix on 0.3.0.1-alpha. Tracked as TROVE-2017- 006 and CVE-2017-0377. o Major bugfixes (compression, zstd): - Correctly detect a full buffer when decompressing a large zstd- compressed input. Previously, we would sometimes treat a full buffer as an error. Fixes bug 22628; bugfix on 0.3.1.1-alpha. o Major bugfixes (directory protocol): - Ensure that we send "304 Not modified" as HTTP status code when a client is attempting to fetch a consensus or consensus diff, and the best one we can send them is one they already have. Fixes bug 22702; bugfix on 0.3.1.1-alpha. o Major bugfixes (entry guards): - When starting with an old consensus, do not add new entry guards unless the consensus is "reasonably live" (under 1 day old). Fixes one root cause of bug 22400; bugfix on 0.3.0.1-alpha. o Minor features (bug mitigation, diagnostics, logging): - Avoid an assertion failure, and log a better error message, when unable to remove a file from the consensus cache on Windows. Attempts to mitigate and diagnose bug 22752. o Minor features (geoip): - Update geoip and geoip6 to the June 8 2017 Maxmind GeoLite2 Country database. o Minor bugfixes (compression): - When compressing or decompressing a buffer, check for a failure to create a compression object. Fixes bug 22626; bugfix on 0.3.1.1-alpha. - When decompressing a buffer, check for extra data after the end of the compressed data. Fixes bug 22629; bugfix on 0.3.1.1-alpha. - When decompressing an object received over an anonymous directory connection, if we have already decompressed it using an acceptable compression method, do not reject it for looking like an unacceptable compression method. Fixes part of bug 22670; bugfix on 0.3.1.1-alpha. - When serving directory votes compressed with zlib, do not claim to have compressed them with zstd. Fixes bug 22669; bugfix on 0.3.1.1-alpha. - When spooling compressed data to an output buffer, don't try to spool more data when there is no more data to spool and we are not trying to flush the input. Previously, we would sometimes launch compression requests with nothing to do, which interferes with our 22672 checks. Fixes bug 22719; bugfix on 0.2.0.16-alpha. o Minor bugfixes (defensive programming): - Detect and break out of infinite loops in our compression code. We don't think that any such loops exist now, but it's best to be safe. Closes ticket 22672. - Fix a memset() off the end of an array when packing cells. This bug should be harmless in practice, since the corrupted bytes are still in the same structure, and are always padding bytes, ignored, or immediately overwritten, depending on compiler behavior. Nevertheless, because the memset()'s purpose is to make sure that any other cell-handling bugs can't expose bytes to the network, we need to fix it. Fixes bug 22737; bugfix on 0.2.4.11-alpha. Fixes CID 1401591. o Minor bugfixes (linux seccomp2 sandbox): - Permit the fchmod system call, to avoid crashing on startup when starting with the seccomp2 sandbox and an unexpected set of permissions on the data directory or its contents. Fixes bug 22516; bugfix on 0.2.5.4-alpha. - Fix a crash in the LZMA module, when the sandbox was enabled, and liblzma would allocate more than 16 MB of memory. We solve this by bumping the mprotect() limit in the sandbox module from 16 MB to 20 MB. Fixes bug 22751; bugfix on 0.3.1.1-alpha. o Minor bugfixes (logging): - When decompressing, do not warn if we fail to decompress using a compression method that we merely guessed. Fixes part of bug 22670; bugfix on 0.1.1.14-alpha. - When decompressing, treat mismatch between content-encoding and actual compression type as a protocol warning. Fixes part of bug 22670; bugfix on 0.1.1.9-alpha. - Downgrade "assigned_to_cpuworker failed" message to info-level severity. In every case that can reach it, either a better warning has already been logged, or no warning is warranted. Fixes bug 22356; bugfix on 0.2.6.3-alpha. - Demote a warn that was caused by libevent delays to info if netflow padding is less than 4.5 seconds late, or to notice if it is more (4.5 seconds is the amount of time that a netflow record might be emitted after, if we chose the maximum timeout). Fixes bug 22212; bugfix on 0.3.1.1-alpha. o Minor bugfixes (process behavior): - When exiting because of an error, always exit with a nonzero exit status. Previously, we would fail to report an error in our exit status in cases related to __OwningControllerProcess failure, lockfile contention, and Ed25519 key initialization. Fixes bug 22720; bugfix on versions 0.2.1.6-alpha, 0.2.2.28-beta, and 0.2.7.2-alpha respectively. Reported by "f55jwk4f"; patch from "huyvq". o Documentation: - Add a manpage description for the key-pinning-journal file. Closes ticket 22347. - Correctly note that bandwidth accounting values are stored in the state file, and the bw_accounting file is now obsolete. Closes ticket 16082. - Document more of the files in the Tor data directory, including cached-extrainfo, secret_onion_key{,_ntor}.old, hidserv-stats, approved-routers, sr-random, and diff-cache. Found while fixing ticket 22347. Changes in version 0.3.0.9 - 2017-06-29 Tor 0.3.0.9 fixes a path selection bug that would allow a client to use a guard that was in the same network family as a chosen exit relay. This is a security regression; all clients running earlier versions of 0.3.0.x or 0.3.1.x should upgrade to 0.3.0.9 or 0.3.1.4-alpha. This release also backports several other bugfixes from the 0.3.1.x series. o Major bugfixes (path selection, security, backport from 0.3.1.4-alpha): - When choosing which guard to use for a circuit, avoid the exit's family along with the exit itself. Previously, the new guard selection logic avoided the exit, but did not consider its family. Fixes bug 22753; bugfix on 0.3.0.1-alpha. Tracked as TROVE-2017- 006 and CVE-2017-0377. o Major bugfixes (entry guards, backport from 0.3.1.1-alpha): - Don't block bootstrapping when a primary bridge is offline and we can't get its descriptor. Fixes bug 22325; fixes one case of bug 21969; bugfix on 0.3.0.3-alpha. o Major bugfixes (entry guards, backport from 0.3.1.4-alpha): - When starting with an old consensus, do not add new entry guards unless the consensus is "reasonably live" (under 1 day old). Fixes one root cause of bug 22400; bugfix on 0.3.0.1-alpha. o Minor features (geoip): - Update geoip and geoip6 to the June 8 2017 Maxmind GeoLite2 Country database. o Minor bugfixes (voting consistency, backport from 0.3.1.1-alpha): - Reject version numbers with non-numeric prefixes (such as +, -, or whitespace). Disallowing whitespace prevents differential version parsing between POSIX-based and Windows platforms. Fixes bug 21507 and part of 21508; bugfix on 0.0.8pre1. o Minor bugfixes (linux seccomp2 sandbox, backport from 0.3.1.4-alpha): - Permit the fchmod system call, to avoid crashing on startup when starting with the seccomp2 sandbox and an unexpected set of permissions on the data directory or its contents. Fixes bug 22516; bugfix on 0.2.5.4-alpha. o Minor bugfixes (defensive programming, backport from 0.3.1.4-alpha): - Fix a memset() off the end of an array when packing cells. This bug should be harmless in practice, since the corrupted bytes are still in the same structure, and are always padding bytes, ignored, or immediately overwritten, depending on compiler behavior. Nevertheless, because the memset()'s purpose is to make sure that any other cell-handling bugs can't expose bytes to the network, we need to fix it. Fixes bug 22737; bugfix on 0.2.4.11-alpha. Fixes CID 1401591. Changes in version 0.3.1.3-alpha - 2017-06-08 Tor 0.3.1.3-alpha fixes a pair of bugs that would allow an attacker to remotely crash a hidden service with an assertion failure. Anyone running a hidden service should upgrade to this version, or to some other version with fixes for TROVE-2017-004 and TROVE-2017-005. Tor 0.3.1.3-alpha also includes fixes for several key management bugs that sometimes made relays unreliable, as well as several other bugfixes described below. o Major bugfixes (hidden service, relay, security): - Fix a remotely triggerable assertion failure when a hidden service handles a malformed BEGIN cell. Fixes bug 22493, tracked as TROVE-2017-004 and as CVE-2017-0375; bugfix on 0.3.0.1-alpha. - Fix a remotely triggerable assertion failure caused by receiving a BEGIN_DIR cell on a hidden service rendezvous circuit. Fixes bug 22494, tracked as TROVE-2017-005 and CVE-2017-0376; bugfix on 0.2.2.1-alpha. o Major bugfixes (relay, link handshake): - When performing the v3 link handshake on a TLS connection, report that we have the x509 certificate that we actually used on that connection, even if we have changed certificates since that connection was first opened. Previously, we would claim to have used our most recent x509 link certificate, which would sometimes make the link handshake fail. Fixes one case of bug 22460; bugfix on 0.2.3.6-alpha. o Major bugfixes (relays, key management): - Regenerate link and authentication certificates whenever the key that signs them changes; also, regenerate link certificates whenever the signed key changes. Previously, these processes were only weakly coupled, and we relays could (for minutes to hours) wind up with an inconsistent set of keys and certificates, which other relays would not accept. Fixes two cases of bug 22460; bugfix on 0.3.0.1-alpha. - When sending an Ed25519 signing->link certificate in a CERTS cell, send the certificate that matches the x509 certificate that we used on the TLS connection. Previously, there was a race condition if the TLS context rotated after we began the TLS handshake but before we sent the CERTS cell. Fixes a case of bug 22460; bugfix on 0.3.0.1-alpha. o Major bugfixes (torrc, crash): - Fix a crash bug when using %include in torrc. Fixes bug 22417; bugfix on 0.3.1.1-alpha. Patch by Daniel Pinto. o Minor features (code style): - Add "Falls through" comments to our codebase, in order to silence GCC 7's -Wimplicit-fallthrough warnings. Patch from Andreas Stieger. Closes ticket 22446. o Minor features (diagnostic): - Add logging messages to try to diagnose a rare bug that seems to generate RSA->Ed25519 cross-certificates dated in the 1970s. We think this is happening because of incorrect system clocks, but we'd like to know for certain. Diagnostic for bug 22466. o Minor bugfixes (correctness): - Avoid undefined behavior when parsing IPv6 entries from the geoip6 file. Fixes bug 22490; bugfix on 0.2.4.6-alpha. o Minor bugfixes (directory protocol): - Check for libzstd >= 1.1, because older versions lack the necessary streaming API. Fixes bug 22413; bugfix on 0.3.1.1-alpha. o Minor bugfixes (link handshake): - Lower the lifetime of the RSA->Ed25519 cross-certificate to six months, and regenerate it when it is within one month of expiring. Previously, we had generated this certificate at startup with a ten-year lifetime, but that could lead to weird behavior when Tor was started with a grossly inaccurate clock. Mitigates bug 22466; mitigation on 0.3.0.1-alpha. o Minor bugfixes (storage directories): - Always check for underflows in the cached storage directory usage. If the usage does underflow, re-calculate it. Also, avoid a separate underflow when the usage is not known. Fixes bug 22424; bugfix on 0.3.1.1-alpha. o Minor bugfixes (unit tests): - The unit tests now pass on systems where localhost is misconfigured to some IPv4 address other than 127.0.0.1. Fixes bug 6298; bugfix on 0.0.9pre2. o Documentation: - Clarify the manpage for the (deprecated) torify script. Closes ticket 6892. Changes in version 0.3.0.8 - 2017-06-08 Tor 0.3.0.8 fixes a pair of bugs that would allow an attacker to remotely crash a hidden service with an assertion failure. Anyone running a hidden service should upgrade to this version, or to some other version with fixes for TROVE-2017-004 and TROVE-2017-005. Tor 0.3.0.8 also includes fixes for several key management bugs that sometimes made relays unreliable, as well as several other bugfixes described below. o Major bugfixes (hidden service, relay, security, backport from 0.3.1.3-alpha): - Fix a remotely triggerable assertion failure when a hidden service handles a malformed BEGIN cell. Fixes bug 22493, tracked as TROVE-2017-004 and as CVE-2017-0375; bugfix on 0.3.0.1-alpha. - Fix a remotely triggerable assertion failure caused by receiving a BEGIN_DIR cell on a hidden service rendezvous circuit. Fixes bug 22494, tracked as TROVE-2017-005 and CVE-2017-0376; bugfix on 0.2.2.1-alpha. o Major bugfixes (relay, link handshake, backport from 0.3.1.3-alpha): - When performing the v3 link handshake on a TLS connection, report that we have the x509 certificate that we actually used on that connection, even if we have changed certificates since that connection was first opened. Previously, we would claim to have used our most recent x509 link certificate, which would sometimes make the link handshake fail. Fixes one case of bug 22460; bugfix on 0.2.3.6-alpha. o Major bugfixes (relays, key management, backport from 0.3.1.3-alpha): - Regenerate link and authentication certificates whenever the key that signs them changes; also, regenerate link certificates whenever the signed key changes. Previously, these processes were only weakly coupled, and we relays could (for minutes to hours) wind up with an inconsistent set of keys and certificates, which other relays would not accept. Fixes two cases of bug 22460; bugfix on 0.3.0.1-alpha. - When sending an Ed25519 signing->link certificate in a CERTS cell, send the certificate that matches the x509 certificate that we used on the TLS connection. Previously, there was a race condition if the TLS context rotated after we began the TLS handshake but before we sent the CERTS cell. Fixes a case of bug 22460; bugfix on 0.3.0.1-alpha. o Major bugfixes (hidden service v3, backport from 0.3.1.1-alpha): - Stop rejecting v3 hidden service descriptors because their size did not match an old padding rule. Fixes bug 22447; bugfix on 0.3.0.1-alpha. o Minor features (fallback directory list, backport from 0.3.1.3-alpha): - Replace the 177 fallbacks originally introduced in Tor 0.2.9.8 in December 2016 (of which ~126 were still functional) with a list of 151 fallbacks (32 new, 119 unchanged, 58 removed) generated in May 2017. Resolves ticket 21564. o Minor bugfixes (configuration, backport from 0.3.1.1-alpha): - Do not crash when starting with LearnCircuitBuildTimeout 0. Fixes bug 22252; bugfix on 0.2.9.3-alpha. o Minor bugfixes (correctness, backport from 0.3.1.3-alpha): - Avoid undefined behavior when parsing IPv6 entries from the geoip6 file. Fixes bug 22490; bugfix on 0.2.4.6-alpha. o Minor bugfixes (link handshake, backport from 0.3.1.3-alpha): - Lower the lifetime of the RSA->Ed25519 cross-certificate to six months, and regenerate it when it is within one month of expiring. Previously, we had generated this certificate at startup with a ten-year lifetime, but that could lead to weird behavior when Tor was started with a grossly inaccurate clock. Mitigates bug 22466; mitigation on 0.3.0.1-alpha. o Minor bugfixes (memory leak, directory authority, backport from 0.3.1.2-alpha): - When directory authorities reject a router descriptor due to keypinning, free the router descriptor rather than leaking the memory. Fixes bug 22370; bugfix on 0.2.7.2-alpha. Changes in version 0.2.9.11 - 2017-06-08 Tor 0.2.9.11 backports a fix for a bug that would allow an attacker to remotely crash a hidden service with an assertion failure. Anyone running a hidden service should upgrade to this version, or to some other version with fixes for TROVE-2017-005. (Versions before 0.3.0 are not affected by TROVE-2017-004.) Tor 0.2.9.11 also backports fixes for several key management bugs that sometimes made relays unreliable, as well as several other bugfixes described below. o Major bugfixes (hidden service, relay, security, backport from 0.3.1.3-alpha): - Fix a remotely triggerable assertion failure caused by receiving a BEGIN_DIR cell on a hidden service rendezvous circuit. Fixes bug 22494, tracked as TROVE-2017-005 and CVE-2017-0376; bugfix on 0.2.2.1-alpha. o Major bugfixes (relay, link handshake, backport from 0.3.1.3-alpha): - When performing the v3 link handshake on a TLS connection, report that we have the x509 certificate that we actually used on that connection, even if we have changed certificates since that connection was first opened. Previously, we would claim to have used our most recent x509 link certificate, which would sometimes make the link handshake fail. Fixes one case of bug 22460; bugfix on 0.2.3.6-alpha. o Minor features (fallback directory list, backport from 0.3.1.3-alpha): - Replace the 177 fallbacks originally introduced in Tor 0.2.9.8 in December 2016 (of which ~126 were still functional) with a list of 151 fallbacks (32 new, 119 unchanged, 58 removed) generated in May 2017. Resolves ticket 21564. o Minor features (future-proofing, backport from 0.3.0.7): - Tor no longer refuses to download microdescriptors or descriptors if they are listed as "published in the future". This change will eventually allow us to stop listing meaningful "published" dates in microdescriptor consensuses, and thereby allow us to reduce the resources required to download consensus diffs by over 50%. Implements part of ticket 21642; implements part of proposal 275. o Minor features (directory authorities, backport from 0.3.0.4-rc) - Directory authorities now reject relays running versions 0.2.9.1-alpha through 0.2.9.4-alpha, because those relays suffer from bug 20499 and don't keep their consensus cache up-to-date. Resolves ticket 20509. o Minor features (geoip): - Update geoip and geoip6 to the May 2 2017 Maxmind GeoLite2 Country database. o Minor bugfixes (control port, backport from 0.3.0.6): - The GETINFO extra-info/digest/ command was broken because of a wrong base16 decode return value check, introduced when refactoring that API. Fixes bug 22034; bugfix on 0.2.9.1-alpha. o Minor bugfixes (correctness, backport from 0.3.1.3-alpha): - Avoid undefined behavior when parsing IPv6 entries from the geoip6 file. Fixes bug 22490; bugfix on 0.2.4.6-alpha. o Minor bugfixes (Linux seccomp2 sandbox, backport from 0.3.0.7): - The getpid() system call is now permitted under the Linux seccomp2 sandbox, to avoid crashing with versions of OpenSSL (and other libraries) that attempt to learn the process's PID by using the syscall rather than the VDSO code. Fixes bug 21943; bugfix on 0.2.5.1-alpha. o Minor bugfixes (memory leak, directory authority, backport from 0.3.1.2-alpha): - When directory authorities reject a router descriptor due to keypinning, free the router descriptor rather than leaking the memory. Fixes bug 22370; bugfix on 0.2.7.2-alpha. Changes in version 0.2.8.14 - 2017-06-08 Tor 0.2.7.8 backports a fix for a bug that would allow an attacker to remotely crash a hidden service with an assertion failure. Anyone running a hidden service should upgrade to this version, or to some other version with fixes for TROVE-2017-005. (Versions before 0.3.0 are not affected by TROVE-2017-004.) o Major bugfixes (hidden service, relay, security): - Fix a remotely triggerable assertion failure caused by receiving a BEGIN_DIR cell on a hidden service rendezvous circuit. Fixes bug 22494, tracked as TROVE-2017-005 and CVE-2017-0376; bugfix on 0.2.2.1-alpha. o Minor features (geoip): - Update geoip and geoip6 to the May 2 2017 Maxmind GeoLite2 Country database. o Minor features (fallback directory list, backport from 0.3.1.3-alpha): - Replace the 177 fallbacks originally introduced in Tor 0.2.9.8 in December 2016 (of which ~126 were still functional) with a list of 151 fallbacks (32 new, 119 unchanged, 58 removed) generated in May 2017. Resolves ticket 21564. o Minor bugfixes (correctness): - Avoid undefined behavior when parsing IPv6 entries from the geoip6 file. Fixes bug 22490; bugfix on 0.2.4.6-alpha. Changes in version 0.2.7.8 - 2017-06-08 Tor 0.2.7.8 backports a fix for a bug that would allow an attacker to remotely crash a hidden service with an assertion failure. Anyone running a hidden service should upgrade to this version, or to some other version with fixes for TROVE-2017-005. (Versions before 0.3.0 are not affected by TROVE-2017-004.) o Major bugfixes (hidden service, relay, security): - Fix a remotely triggerable assertion failure caused by receiving a BEGIN_DIR cell on a hidden service rendezvous circuit. Fixes bug 22494, tracked as TROVE-2017-005 and CVE-2017-0376; bugfix on 0.2.2.1-alpha. o Minor features (geoip): - Update geoip and geoip6 to the May 2 2017 Maxmind GeoLite2 Country database. o Minor bugfixes (correctness): - Avoid undefined behavior when parsing IPv6 entries from the geoip6 file. Fixes bug 22490; bugfix on 0.2.4.6-alpha. Changes in version 0.2.6.12 - 2017-06-08 Tor 0.2.6.12 backports a fix for a bug that would allow an attacker to remotely crash a hidden service with an assertion failure. Anyone running a hidden service should upgrade to this version, or to some other version with fixes for TROVE-2017-005. (Versions before 0.3.0 are not affected by TROVE-2017-004.) o Major bugfixes (hidden service, relay, security): - Fix a remotely triggerable assertion failure caused by receiving a BEGIN_DIR cell on a hidden service rendezvous circuit. Fixes bug 22494, tracked as TROVE-2017-005 and CVE-2017-0376; bugfix on 0.2.2.1-alpha. o Minor features (geoip): - Update geoip and geoip6 to the May 2 2017 Maxmind GeoLite2 Country database. o Minor bugfixes (correctness): - Avoid undefined behavior when parsing IPv6 entries from the geoip6 file. Fixes bug 22490; bugfix on 0.2.4.6-alpha. Changes in version 0.2.5.14 - 2017-06-08 Tor 0.2.5.14 backports a fix for a bug that would allow an attacker to remotely crash a hidden service with an assertion failure. Anyone running a hidden service should upgrade to this version, or to some other version with fixes for TROVE-2017-005. (Versions before 0.3.0 are not affected by TROVE-2017-004.) o Major bugfixes (hidden service, relay, security): - Fix a remotely triggerable assertion failure caused by receiving a BEGIN_DIR cell on a hidden service rendezvous circuit. Fixes bug 22494, tracked as TROVE-2017-005 and CVE-2017-0376; bugfix on 0.2.2.1-alpha. o Minor features (geoip): - Update geoip and geoip6 to the May 2 2017 Maxmind GeoLite2 Country database. o Minor bugfixes (correctness): - Avoid undefined behavior when parsing IPv6 entries from the geoip6 file. Fixes bug 22490; bugfix on 0.2.4.6-alpha. Changes in version 0.2.4.29 - 2017-06-08 Tor 0.2.4.29 backports a fix for a bug that would allow an attacker to remotely crash a hidden service with an assertion failure. Anyone running a hidden service should upgrade to this version, or to some other version with fixes for TROVE-2017-005. (Versions before 0.3.0 are not affected by TROVE-2017-004.) o Major bugfixes (hidden service, relay, security): - Fix a remotely triggerable assertion failure caused by receiving a BEGIN_DIR cell on a hidden service rendezvous circuit. Fixes bug 22494, tracked as TROVE-2017-005 and CVE-2017-0376; bugfix on 0.2.2.1-alpha. o Minor features (geoip): - Update geoip and geoip6 to the May 2 2017 Maxmind GeoLite2 Country database. o Minor bugfixes (correctness): - Avoid undefined behavior when parsing IPv6 entries from the geoip6 file. Fixes bug 22490; bugfix on 0.2.4.6-alpha. Changes in version 0.3.1.2-alpha - 2017-05-26 Tor 0.3.1.2-alpha is the second release in the 0.3.1.x series. It fixes a few bugs found while testing 0.3.1.1-alpha, including a memory corruption bug that affected relay stability. o Major bugfixes (crash, relay): - Fix a memory-corruption bug in relays that set MyFamily. Previously, they would double-free MyFamily elements when making the next descriptor or when changing their configuration. Fixes bug 22368; bugfix on 0.3.1.1-alpha. o Minor bugfixes (logging): - Log a better message when a directory authority replies to an upload with an unexpected status code. Fixes bug 11121; bugfix on 0.1.0.1-rc. o Minor bugfixes (memory leak, directory authority): - When directory authorities reject a router descriptor due to keypinning, free the router descriptor rather than leaking the memory. Fixes bug 22370; bugfix on 0.2.7.2-alpha. Changes in version 0.3.1.1-alpha - 2017-05-22 Tor 0.3.1.1-alpha is the first release in the 0.3.1.x series. It reduces the bandwidth usage for Tor's directory protocol, adds some basic padding to resist netflow-based traffic analysis and to serve as the basis of other padding in the future, and adds rust support to the build system. It also contains numerous other small features and improvements to security, correctness, and performance. Below are the changes since 0.3.0.7. o Major features (directory protocol): - Tor relays and authorities can now serve clients an abbreviated version of the consensus document, containing only the changes since an older consensus document that the client holds. Clients now request these documents when available. When both client and server use this new protocol, they will use far less bandwidth (up to 94% less) to keep the client's consensus up-to-date. Implements proposal 140; closes ticket 13339. Based on work by Daniel Martí. - Tor can now compress directory traffic with lzma or with zstd compression algorithms, which can deliver better bandwidth performance. Because lzma is computationally expensive, it's only used for documents that can be compressed once and served many times. Support for these algorithms requires that tor is built with the libzstd and/or liblzma libraries available. Implements proposal 278; closes ticket 21662. - Relays now perform the more expensive compression operations, and consensus diff generation, in worker threads. This separation avoids delaying the main thread when a new consensus arrives. o Major features (experimental): - Tor can now build modules written in Rust. To turn this on, pass the "--enable-rust" flag to the configure script. It's not time to get excited yet: currently, there is no actual Rust functionality beyond some simple glue code, and a notice at startup to tell you that Rust is running. Still, we hope that programmers and packagers will try building Tor with Rust support, so that we can find issues and solve portability problems. Closes ticket 22106. o Major features (traffic analysis resistance): - Connections between clients and relays now send a padding cell in each direction every 1.5 to 9.5 seconds (tunable via consensus parameters). This padding will not resist specialized eavesdroppers, but it should be enough to make many ISPs' routine network flow logging less useful in traffic analysis against Tor users. Padding is negotiated using Tor's link protocol, so both relays and clients must upgrade for this to take effect. Clients may still send padding despite the relay's version by setting ConnectionPadding 1 in torrc, and may disable padding by setting ConnectionPadding 0 in torrc. Padding may be minimized for mobile users with the torrc option ReducedConnectionPadding. Implements Proposal 251 and Section 2 of Proposal 254; closes ticket 16861. - Relays will publish 24 hour totals of padding and non-padding cell counts to their extra-info descriptors, unless PaddingStatistics 0 is set in torrc. These 24 hour totals are also rounded to multiples of 10000. o Major bugfixes (connection usage): - We use NETINFO cells to try to determine if both relays involved in a connection will agree on the canonical status of that connection. We prefer the connections where this is the case for extend cells, and try to close connections where relays disagree on their canonical status early. Also, we now prefer the oldest valid connection for extend cells. These two changes should reduce the number of long-term connections that are kept open between relays. Fixes bug 17604; bugfix on 0.2.5.5-alpha. - Relays now log hourly statistics (look for "channel_check_for_duplicates" lines) on the total number of connections to other relays. If the number of connections per relay is unexpectedly large, this log message is at notice level. Otherwise it is at info. o Major bugfixes (entry guards): - Don't block bootstrapping when a primary bridge is offline and we can't get its descriptor. Fixes bug 22325; fixes one case of bug 21969; bugfix on 0.3.0.3-alpha. o Major bugfixes (linux TPROXY support): - Fix a typo that had prevented TPROXY-based transparent proxying from working under Linux. Fixes bug 18100; bugfix on 0.2.6.3-alpha. Patch from "d4fq0fQAgoJ". o Minor features (security, windows): - Enable a couple of pieces of Windows hardening: one (HeapEnableTerminationOnCorruption) that has been on-by-default since Windows 8, and unavailable before Windows 7; and one (PROCESS_DEP_DISABLE_ATL_THUNK_EMULATION) which we believe doesn't affect us, but shouldn't do any harm. Closes ticket 21953. o Minor features (config options): - Allow "%include" directives in torrc configuration files. These directives import the settings from other files, or from all the files in a directory. Closes ticket 1922. Code by Daniel Pinto. - Make SAVECONF return an error when overwriting a torrc that has includes. Using SAVECONF with the FORCE option will allow it to overwrite torrc even if includes are used. Related to ticket 1922. - Add "GETINFO config-can-saveconf" to tell controllers if SAVECONF will work without the FORCE option. Related to ticket 1922. o Minor features (controller): - Warn the first time that a controller requests data in the long- deprecated 'GETINFO network-status' format. Closes ticket 21703. o Minor features (defaults): - The default value for UseCreateFast is now 0: clients which haven't yet received a consensus document will now use a proper ntor handshake to talk to their directory servers whenever they can. Closes ticket 21407. - Onion key rotation and expiry intervals are now defined as a network consensus parameter, per proposal 274. The default lifetime of an onion key is increased from 7 to 28 days. Old onion keys will expire after 7 days by default. This change will make consensus diffs much smaller, and save significant bandwidth. Closes ticket 21641. o Minor features (fallback directory list): - Update the fallback directory mirror whitelist and blacklist based on operator emails. Closes task 21121. - Replace the 177 fallbacks originally introduced in Tor 0.2.9.8 in December 2016 (of which ~126 were still functional) with a list of 151 fallbacks (32 new, 119 unchanged, 58 removed) generated in May 2017. Resolves ticket 21564. o Minor features (hidden services, logging): - Log a message when a hidden service descriptor has fewer introduction points than specified in HiddenServiceNumIntroductionPoints. Closes tickets 21598. - Log a message when a hidden service reaches its introduction point circuit limit, and when that limit is reset. Follow up to ticket 21594; closes ticket 21622. - Warn user if multiple entries in EntryNodes and at least one HiddenService are used together. Pinning EntryNodes along with a hidden service can be possibly harmful; for instance see ticket 14917 or 21155. Closes ticket 21155. o Minor features (linux seccomp2 sandbox): - We now have a document storage backend compatible with the Linux seccomp2 sandbox. This backend is used for consensus documents and diffs between them; in the long term, we'd like to use it for unparseable directory material too. Closes ticket 21645 - Increase the maximum allowed size passed to mprotect(PROT_WRITE) from 1MB to 16MB. This was necessary with the glibc allocator in order to allow worker threads to allocate more memory -- which in turn is necessary because of our new use of worker threads for compression. Closes ticket 22096. o Minor features (logging): - Log files are no longer created world-readable by default. (Previously, most distributors would store the logs in a non- world-readable location to prevent inappropriate access. This change is an extra precaution.) Closes ticket 21729; patch from toralf. o Minor features (performance): - Our Keccak (SHA-3) implementation now accesses memory more efficiently, especially on little-endian systems. Closes ticket 21737. - Add an O(1) implementation of channel_find_by_global_id(), to speed some controller functions. o Minor features (relay, configuration): - The MyFamily option may now be repeated as many times as desired, for relays that want to configure large families. Closes ticket 4998; patch by Daniel Pinto. o Minor features (safety): - Add an explicit check to extrainfo_parse_entry_from_string() for NULL inputs. We don't believe this can actually happen, but it may help silence a warning from the Clang analyzer. Closes ticket 21496. o Minor features (testing): - Add a "--disable-memory-sentinels" feature to help with fuzzing. When Tor is compiled with this option, we disable a number of redundant memory-safety failsafes that are intended to stop bugs from becoming security issues. This makes it easier to hunt for bugs that would be security issues without the failsafes turned on. Closes ticket 21439. - Add a general event-tracing instrumentation support to Tor. This subsystem will enable developers and researchers to add fine- grained instrumentation to their Tor instances, for use when examining Tor network performance issues. There are no trace events yet, and event-tracing is off by default unless enabled at compile time. Implements ticket 13802. - Improve our version parsing tests: add tests for typical version components, add tests for invalid versions, including numeric range and non-numeric prefixes. Unit tests 21278, 21450, and 21507. Partially implements 21470. o Minor bugfixes (bandwidth accounting): - Roll over monthly accounting at the configured hour and minute, rather than always at 00:00. Fixes bug 22245; bugfix on 0.0.9rc1. Found by Andrey Karpov with PVS-Studio. o Minor bugfixes (code correctness): - Accurately identify client connections by their lack of peer authentication. This means that we bail out earlier if asked to extend to a client. Follow-up to 21407. Fixes bug 21406; bugfix on 0.2.4.23. o Minor bugfixes (configuration): - Do not crash when starting with LearnCircuitBuildTimeout 0. Fixes bug 22252; bugfix on 0.2.9.3-alpha. o Minor bugfixes (connection lifespan): - Allow more control over how long TLS connections are kept open: unify CircuitIdleTimeout and PredictedPortsRelevanceTime into a single option called CircuitsAvailableTimeout. Also, allow the consensus to control the default values for both this preference and the lifespan of relay-to-relay connections. Fixes bug 17592; bugfix on 0.2.5.5-alpha. - Increase the initial circuit build timeout testing frequency, to help ensure that ReducedConnectionPadding clients finish learning a timeout before their orconn would expire. The initial testing rate was set back in the days of TAP and before the Tor Browser updater, when we had to be much more careful about new clients making lots of circuits. With this change, a circuit build timeout is learned in about 15-20 minutes, instead of 100-120 minutes. o Minor bugfixes (controller): - GETINFO onions/current and onions/detached no longer respond with 551 on empty lists. Fixes bug 21329; bugfix on 0.2.7.1-alpha. - Trigger HS descriptor events on the control port when the client fails to pick a hidden service directory for a hidden service. This can happen if all the hidden service directories are in ExcludeNodes, or they have all been queried within the last 15 minutes. Fixes bug 22042; bugfix on 0.2.5.2-alpha. o Minor bugfixes (directory authority): - When rejecting a router descriptor for running an obsolete version of Tor without ntor support, warn about the obsolete tor version, not the missing ntor key. Fixes bug 20270; bugfix on 0.2.9.3-alpha. - Prevent the shared randomness subsystem from asserting when initialized by a bridge authority with an incomplete configuration file. Fixes bug 21586; bugfix on 0.2.9.8. o Minor bugfixes (exit-side DNS): - Fix an untriggerable assertion that checked the output of a libevent DNS error, so that the assertion actually behaves as expected. Fixes bug 22244; bugfix on 0.2.0.20-rc. Found by Andrey Karpov using PVS-Studio. o Minor bugfixes (fallback directories): - Make the usage example in updateFallbackDirs.py actually work, and explain what it does. Fixes bug 22270; bugfix on 0.3.0.3-alpha. - Decrease the guard flag average required to be a fallback. This allows us to keep relays that have their guard flag removed when they restart. Fixes bug 20913; bugfix on 0.2.8.1-alpha. - Decrease the minimum number of fallbacks to 100. Fixes bug 20913; bugfix on 0.2.8.1-alpha. - Make sure fallback directory mirrors have the same address, port, and relay identity key for at least 30 days before they are selected. Fixes bug 20913; bugfix on 0.2.8.1-alpha. o Minor bugfixes (hidden services): - Stop printing a cryptic warning when a hidden service gets a request to connect to a virtual port that it hasn't configured. Fixes bug 16706; bugfix on 0.2.6.3-alpha. - Simplify hidden service descriptor creation by using an existing flag to check if an introduction point is established. Fixes bug 21599; bugfix on 0.2.7.2-alpha. o Minor bugfixes (memory leak): - Fix a small memory leak at exit from the backtrace handler code. Fixes bug 21788; bugfix on 0.2.5.2-alpha. Patch from Daniel Pinto. o Minor bugfixes (protocol, logging): - Downgrade a log statement about unexpected relay cells from "bug" to "protocol warning", because there is at least one use case where it can be triggered by a buggy tor implementation. Fixes bug 21293; bugfix on 0.1.1.14-alpha. o Minor bugfixes (testing): - Use unbuffered I/O for utility functions around the process_handle_t type. This fixes unit test failures reported on OpenBSD and FreeBSD. Fixes bug 21654; bugfix on 0.2.3.1-alpha. - Make display of captured unit test log messages consistent. Fixes bug 21510; bugfix on 0.2.9.3-alpha. - Make test-network.sh always call chutney's test-network.sh. Previously, this only worked on systems which had bash installed, due to some bash-specific code in the script. Fixes bug 19699; bugfix on 0.3.0.4-rc. Follow-up to ticket 21581. o Minor bugfixes (voting consistency): - Reject version numbers with non-numeric prefixes (such as +, -, or whitespace). Disallowing whitespace prevents differential version parsing between POSIX-based and Windows platforms. Fixes bug 21507 and part of 21508; bugfix on 0.0.8pre1. o Minor bugfixes (windows, relay): - Resolve "Failure from drain_fd: No error" warnings on Windows relays. Fixes bug 21540; bugfix on 0.2.6.3-alpha. o Code simplification and refactoring: - Break up the 630-line function connection_dir_client_reached_eof() into a dozen smaller functions. This change should help maintainability and readability of the client directory code. - Isolate our use of the openssl headers so that they are only included from our crypto wrapper modules, and from tests that examine those modules' internals. Closes ticket 21841. - Simplify our API to launch directory requests, making it more extensible and less error-prone. Now it's easier to add extra headers to directory requests. Closes ticket 21646. - Our base64 decoding functions no longer overestimate the output space that they need when parsing unpadded inputs. Closes ticket 17868. - Remove unused "ROUTER_ADDED_NOTIFY_GENERATOR" internal value. Resolves ticket 22213. - The logic that directory caches use to spool request to clients, serving them one part at a time so as not to allocate too much memory, has been refactored for consistency. Previously there was a separate spooling implementation per type of spoolable data. Now there is one common spooling implementation, with extensible data types. Closes ticket 21651. - Tor's compression module now supports multiple backends. Part of the implementation for proposal 278; closes ticket 21663. o Documentation: - Clarify the behavior of the KeepAliveIsolateSOCKSAuth sub-option. Closes ticket 21873. - Correct documentation about the default DataDirectory value. Closes ticket 21151. - Document the default behavior of NumEntryGuards and NumDirectoryGuards correctly. Fixes bug 21715; bugfix on 0.3.0.1-alpha. - Document key=value pluggable transport arguments for Bridge lines in torrc. Fixes bug 20341; bugfix on 0.2.5.1-alpha. - Note that bandwidth-limiting options don't affect TCP headers or DNS. Closes ticket 17170. o Removed features (configuration options, all in ticket 22060): - These configuration options are now marked Obsolete, and no longer have any effect: AllowInvalidNodes, AllowSingleHopCircuits, AllowSingleHopExits, ExcludeSingleHopRelays, FastFirstHopPK, TLSECGroup, WarnUnsafeSocks. They were first marked as deprecated in 0.2.9.2-alpha and have now been removed. The previous default behavior is now always chosen; the previous (less secure) non- default behavior is now unavailable. - CloseHSClientCircuitsImmediatelyOnTimeout and CloseHSServiceRendCircuitsImmediatelyOnTimeout were deprecated in 0.2.9.2-alpha and now have been removed. HS circuits never close on circuit build timeout; they have a longer timeout period. - {Control,DNS,Dir,Socks,Trans,NATD,OR}ListenAddress were deprecated in 0.2.9.2-alpha and now have been removed. Use the ORPort option (and others) to configure listen-only and advertise-only addresses. o Removed features (tools): - We've removed the tor-checkkey tool from src/tools. Long ago, we used it to help people detect RSA keys that were generated by versions of Debian affected by CVE-2008-0166. But those keys have been out of circulation for ages, and this tool is no longer required. Closes ticket 21842. Changes in version 0.3.0.7 - 2017-05-15 Tor 0.3.0.7 fixes a medium-severity security bug in earlier versions of Tor 0.3.0.x, where an attacker could cause a Tor relay process to exit. Relays running earlier versions of Tor 0.3.0.x should upgrade; clients are not affected. o Major bugfixes (hidden service directory, security): - Fix an assertion failure in the hidden service directory code, which could be used by an attacker to remotely cause a Tor relay process to exit. Relays running earlier versions of Tor 0.3.0.x should upgrade. should upgrade. This security issue is tracked as TROVE-2017-002. Fixes bug 22246; bugfix on 0.3.0.1-alpha. o Minor features: - Update geoip and geoip6 to the May 2 2017 Maxmind GeoLite2 Country database. o Minor features (future-proofing): - Tor no longer refuses to download microdescriptors or descriptors if they are listed as "published in the future". This change will eventually allow us to stop listing meaningful "published" dates in microdescriptor consensuses, and thereby allow us to reduce the resources required to download consensus diffs by over 50%. Implements part of ticket 21642; implements part of proposal 275. o Minor bugfixes (Linux seccomp2 sandbox): - The getpid() system call is now permitted under the Linux seccomp2 sandbox, to avoid crashing with versions of OpenSSL (and other libraries) that attempt to learn the process's PID by using the syscall rather than the VDSO code. Fixes bug 21943; bugfix on 0.2.5.1-alpha. Changes in version 0.3.0.6 - 2017-04-26 Tor 0.3.0.6 is the first stable release of the Tor 0.3.0 series. With the 0.3.0 series, clients and relays now use Ed25519 keys to authenticate their link connections to relays, rather than the old RSA1024 keys that they used before. (Circuit crypto has been Curve25519-authenticated since 0.2.4.8-alpha.) We have also replaced the guard selection and replacement algorithm to behave more robustly in the presence of unreliable networks, and to resist guard- capture attacks. This series also includes numerous other small features and bugfixes, along with more groundwork for the upcoming hidden-services revamp. Per our stable release policy, we plan to support the Tor 0.3.0 release series for at least the next nine months, or for three months after the first stable release of the 0.3.1 series: whichever is longer. If you need a release with long-term support, we recommend that you stay with the 0.2.9 series. Below are the changes since 0.3.0.5-rc. For a list of all changes since 0.2.9, see the ReleaseNotes file. o Minor features (geoip): - Update geoip and geoip6 to the April 4 2017 Maxmind GeoLite2 Country database. o Minor bugfixes (control port): - The GETINFO extra-info/digest/ command was broken because of a wrong base16 decode return value check, introduced when refactoring that API. Fixes bug 22034; bugfix on 0.2.9.1-alpha. o Minor bugfixes (crash prevention): - Fix a (currently untriggerable, but potentially dangerous) crash bug when base32-encoding inputs whose sizes are not a multiple of 5. Fixes bug 21894; bugfix on 0.2.9.1-alpha. Changes in version 0.3.0.5-rc - 2017-04-05 Tor 0.3.0.5-rc fixes a few remaining bugs, large and small, in the 0.3.0 release series. This is the second release candidate in the Tor 0.3.0 series, and has much fewer changes than the first. If we find no new bugs or regressions here, the first stable 0.3.0 release will be nearly identical to it. o Major bugfixes (crash, directory connections): - Fix a rare crash when sending a begin cell on a circuit whose linked directory connection had already been closed. Fixes bug 21576; bugfix on 0.2.9.3-alpha. Reported by Alec Muffett. o Major bugfixes (guard selection): - Fix a guard selection bug where Tor would refuse to bootstrap in some cases if the user swapped a bridge for another bridge in their configuration file. Fixes bug 21771; bugfix on 0.3.0.1-alpha. Reported by "torvlnt33r". o Minor features (geoip): - Update geoip and geoip6 to the March 7 2017 Maxmind GeoLite2 Country database. o Minor bugfix (compilation): - Fix a warning when compiling hs_service.c. Previously, it had no exported symbols when compiled for libor.a, resulting in a compilation warning from clang. Fixes bug 21825; bugfix on 0.3.0.1-alpha. o Minor bugfixes (hidden services): - Make hidden services check for failed intro point connections, even when they have exceeded their intro point creation limit. Fixes bug 21596; bugfix on 0.2.7.2-alpha. Reported by Alec Muffett. - Make hidden services with 8 to 10 introduction points check for failed circuits immediately after startup. Previously, they would wait for 5 minutes before performing their first checks. Fixes bug 21594; bugfix on 0.2.3.9-alpha. Reported by Alec Muffett. o Minor bugfixes (memory leaks): - Fix a memory leak when using GETCONF on a port option. Fixes bug 21682; bugfix on 0.3.0.3-alpha. o Minor bugfixes (relay): - Avoid a double-marked-circuit warning that could happen when we receive DESTROY cells under heavy load. Fixes bug 20059; bugfix on 0.1.0.1-rc. o Minor bugfixes (tests): - Run the entry_guard_parse_from_state_full() test with the time set to a specific date. (The guard state that this test was parsing contained guards that had expired since the test was first written.) Fixes bug 21799; bugfix on 0.3.0.1-alpha. o Documentation: - Update the description of the directory server options in the manual page, to clarify that a relay no longer needs to set DirPort in order to be a directory cache. Closes ticket 21720. Changes in version 0.2.8.13 - 2017-03-03 Tor 0.2.8.13 backports a security fix from later Tor releases. Anybody running Tor 0.2.8.12 or earlier should upgrade to this this release, if for some reason they cannot upgrade to a later release series, and if they build Tor with the --enable-expensive-hardening option. Note that support for Tor 0.2.8.x is ending next year: we will not issue any fixes for the Tor 0.2.8.x series after 1 Jan 2018. If you need a Tor release series with longer-term support, we recommend Tor 0.2.9.x. o Major bugfixes (parsing, backported from 0.3.0.4-rc): - Fix an integer underflow bug when comparing malformed Tor versions. This bug could crash Tor when built with --enable-expensive-hardening, or on Tor 0.2.9.1-alpha through Tor 0.2.9.8, which were built with -ftrapv by default. In other cases it was harmless. Part of TROVE-2017-001. Fixes bug 21278; bugfix on 0.0.8pre1. Found by OSS-Fuzz. o Minor features (geoip): - Update geoip and geoip6 to the February 8 2017 Maxmind GeoLite2 Country database. Changes in version 0.2.7.7 - 2017-03-03 Tor 0.2.7.7 backports a number of security fixes from later Tor releases. Anybody running Tor 0.2.7.6 or earlier should upgrade to this release, if for some reason they cannot upgrade to a later release series. Note that support for Tor 0.2.7.x is ending this year: we will not issue any fixes for the Tor 0.2.7.x series after 1 August 2017. If you need a Tor release series with longer-term support, we recommend Tor 0.2.9.x. o Directory authority changes (backport from 0.2.8.5-rc): - Urras is no longer a directory authority. Closes ticket 19271. o Directory authority changes (backport from 0.2.9.2-alpha): - The "Tonga" bridge authority has been retired; the new bridge authority is "Bifroest". Closes tickets 19728 and 19690. o Directory authority key updates (backport from 0.2.8.1-alpha): - Update the V3 identity key for the dannenberg directory authority: it was changed on 18 November 2015. Closes task 17906. Patch by "teor". o Major bugfixes (parsing, security, backport from 0.2.9.8): - Fix a bug in parsing that could cause clients to read a single byte past the end of an allocated region. This bug could be used to cause hardened clients (built with --enable-expensive-hardening) to crash if they tried to visit a hostile hidden service. Non- hardened clients are only affected depending on the details of their platform's memory allocator. Fixes bug 21018; bugfix on 0.2.0.8-alpha. Found by using libFuzzer. Also tracked as TROVE- 2016-12-002 and as CVE-2016-1254. o Major bugfixes (security, client, DNS proxy, backport from 0.2.8.3-alpha): - Stop a crash that could occur when a client running with DNSPort received a query with multiple address types, and the first address type was not supported. Found and fixed by Scott Dial. Fixes bug 18710; bugfix on 0.2.5.4-alpha. - Prevent a class of security bugs caused by treating the contents of a buffer chunk as if they were a NUL-terminated string. At least one such bug seems to be present in all currently used versions of Tor, and would allow an attacker to remotely crash most Tor instances, especially those compiled with extra compiler hardening. With this defense in place, such bugs can't crash Tor, though we should still fix them as they occur. Closes ticket 20384 (TROVE-2016-10-001). o Major bugfixes (security, pointers, backport from 0.2.8.2-alpha): - Avoid a difficult-to-trigger heap corruption attack when extending a smartlist to contain over 16GB of pointers. Fixes bug 18162; bugfix on 0.1.1.11-alpha, which fixed a related bug incompletely. Reported by Guido Vranken. o Major bugfixes (dns proxy mode, crash, backport from 0.2.8.2-alpha): - Avoid crashing when running as a DNS proxy. Fixes bug 16248; bugfix on 0.2.0.1-alpha. Patch from "cypherpunks". o Major bugfixes (key management, backport from 0.2.8.3-alpha): - If OpenSSL fails to generate an RSA key, do not retain a dangling pointer to the previous (uninitialized) key value. The impact here should be limited to a difficult-to-trigger crash, if OpenSSL is running an engine that makes key generation failures possible, or if OpenSSL runs out of memory. Fixes bug 19152; bugfix on 0.2.1.10-alpha. Found by Yuan Jochen Kang, Suman Jana, and Baishakhi Ray. o Major bugfixes (parsing, backported from 0.3.0.4-rc): - Fix an integer underflow bug when comparing malformed Tor versions. This bug could crash Tor when built with --enable-expensive-hardening, or on Tor 0.2.9.1-alpha through Tor 0.2.9.8, which were built with -ftrapv by default. In other cases it was harmless. Part of TROVE-2017-001. Fixes bug 21278; bugfix on 0.0.8pre1. Found by OSS-Fuzz. o Minor features (security, memory erasure, backport from 0.2.8.1-alpha): - Make memwipe() do nothing when passed a NULL pointer or buffer of zero size. Check size argument to memwipe() for underflow. Fixes bug 18089; bugfix on 0.2.3.25 and 0.2.4.6-alpha. Reported by "gk", patch by "teor". o Minor features (bug-resistance, backport from 0.2.8.2-alpha): - Make Tor survive errors involving connections without a corresponding event object. Previously we'd fail with an assertion; now we produce a log message. Related to bug 16248. o Minor features (geoip): - Update geoip and geoip6 to the February 8 2017 Maxmind GeoLite2 Country database. Changes in version 0.2.6.11 - 2017-03-03 Tor 0.2.6.11 backports a number of security fixes from later Tor releases. Anybody running Tor 0.2.6.10 or earlier should upgrade to this release, if for some reason they cannot upgrade to a later release series. Note that support for Tor 0.2.6.x is ending this year: we will not issue any fixes for the Tor 0.2.6.x series after 1 August 2017. If you need a Tor release series with longer-term support, we recommend Tor 0.2.9.x. o Directory authority changes (backport from 0.2.8.5-rc): - Urras is no longer a directory authority. Closes ticket 19271. o Directory authority changes (backport from 0.2.9.2-alpha): - The "Tonga" bridge authority has been retired; the new bridge authority is "Bifroest". Closes tickets 19728 and 19690. o Directory authority key updates (backport from 0.2.8.1-alpha): - Update the V3 identity key for the dannenberg directory authority: it was changed on 18 November 2015. Closes task 17906. Patch by "teor". o Major features (security fixes, backport from 0.2.9.4-alpha): - Prevent a class of security bugs caused by treating the contents of a buffer chunk as if they were a NUL-terminated string. At least one such bug seems to be present in all currently used versions of Tor, and would allow an attacker to remotely crash most Tor instances, especially those compiled with extra compiler hardening. With this defense in place, such bugs can't crash Tor, though we should still fix them as they occur. Closes ticket 20384 (TROVE-2016-10-001). o Major bugfixes (parsing, security, backport from 0.2.9.8): - Fix a bug in parsing that could cause clients to read a single byte past the end of an allocated region. This bug could be used to cause hardened clients (built with --enable-expensive-hardening) to crash if they tried to visit a hostile hidden service. Non- hardened clients are only affected depending on the details of their platform's memory allocator. Fixes bug 21018; bugfix on 0.2.0.8-alpha. Found by using libFuzzer. Also tracked as TROVE- 2016-12-002 and as CVE-2016-1254. o Major bugfixes (security, client, DNS proxy, backport from 0.2.8.3-alpha): - Stop a crash that could occur when a client running with DNSPort received a query with multiple address types, and the first address type was not supported. Found and fixed by Scott Dial. Fixes bug 18710; bugfix on 0.2.5.4-alpha. o Major bugfixes (security, correctness, backport from 0.2.7.4-rc): - Fix an error that could cause us to read 4 bytes before the beginning of an openssl string. This bug could be used to cause Tor to crash on systems with unusual malloc implementations, or systems with unusual hardening installed. Fixes bug 17404; bugfix on 0.2.3.6-alpha. o Major bugfixes (security, pointers, backport from 0.2.8.2-alpha): - Avoid a difficult-to-trigger heap corruption attack when extending a smartlist to contain over 16GB of pointers. Fixes bug 18162; bugfix on 0.1.1.11-alpha, which fixed a related bug incompletely. Reported by Guido Vranken. o Major bugfixes (dns proxy mode, crash, backport from 0.2.8.2-alpha): - Avoid crashing when running as a DNS proxy. Fixes bug 16248; bugfix on 0.2.0.1-alpha. Patch from "cypherpunks". o Major bugfixes (guard selection, backport from 0.2.7.6): - Actually look at the Guard flag when selecting a new directory guard. When we implemented the directory guard design, we accidentally started treating all relays as if they have the Guard flag during guard selection, leading to weaker anonymity and worse performance. Fixes bug 17772; bugfix on 0.2.4.8-alpha. Discovered by Mohsen Imani. o Major bugfixes (key management, backport from 0.2.8.3-alpha): - If OpenSSL fails to generate an RSA key, do not retain a dangling pointer to the previous (uninitialized) key value. The impact here should be limited to a difficult-to-trigger crash, if OpenSSL is running an engine that makes key generation failures possible, or if OpenSSL runs out of memory. Fixes bug 19152; bugfix on 0.2.1.10-alpha. Found by Yuan Jochen Kang, Suman Jana, and Baishakhi Ray. o Major bugfixes (parsing, backported from 0.3.0.4-rc): - Fix an integer underflow bug when comparing malformed Tor versions. This bug could crash Tor when built with --enable-expensive-hardening, or on Tor 0.2.9.1-alpha through Tor 0.2.9.8, which were built with -ftrapv by default. In other cases it was harmless. Part of TROVE-2017-001. Fixes bug 21278; bugfix on 0.0.8pre1. Found by OSS-Fuzz. o Minor features (security, memory erasure, backport from 0.2.8.1-alpha): - Make memwipe() do nothing when passed a NULL pointer or buffer of zero size. Check size argument to memwipe() for underflow. Fixes bug 18089; bugfix on 0.2.3.25 and 0.2.4.6-alpha. Reported by "gk", patch by "teor". o Minor features (bug-resistance, backport from 0.2.8.2-alpha): - Make Tor survive errors involving connections without a corresponding event object. Previously we'd fail with an assertion; now we produce a log message. Related to bug 16248. o Minor features (geoip): - Update geoip and geoip6 to the February 8 2017 Maxmind GeoLite2 Country database. o Minor bugfixes (compilation, backport from 0.2.7.6): - Fix a compilation warning with Clang 3.6: Do not check the presence of an address which can never be NULL. Fixes bug 17781. Changes in version 0.2.5.13 - 2017-03-03 Tor 0.2.5.13 backports a number of security fixes from later Tor releases. Anybody running Tor 0.2.5.13 or earlier should upgrade to this release, if for some reason they cannot upgrade to a later release series. Note that support for Tor 0.2.5.x is ending next year: we will not issue any fixes for the Tor 0.2.5.x series after 1 May 2018. If you need a Tor release series with longer-term support, we recommend Tor 0.2.9.x. o Directory authority changes (backport from 0.2.8.5-rc): - Urras is no longer a directory authority. Closes ticket 19271. o Directory authority changes (backport from 0.2.9.2-alpha): - The "Tonga" bridge authority has been retired; the new bridge authority is "Bifroest". Closes tickets 19728 and 19690. o Directory authority key updates (backport from 0.2.8.1-alpha): - Update the V3 identity key for the dannenberg directory authority: it was changed on 18 November 2015. Closes task 17906. Patch by "teor". o Major features (security fixes, backport from 0.2.9.4-alpha): - Prevent a class of security bugs caused by treating the contents of a buffer chunk as if they were a NUL-terminated string. At least one such bug seems to be present in all currently used versions of Tor, and would allow an attacker to remotely crash most Tor instances, especially those compiled with extra compiler hardening. With this defense in place, such bugs can't crash Tor, though we should still fix them as they occur. Closes ticket 20384 (TROVE-2016-10-001). o Major bugfixes (parsing, security, backport from 0.2.9.8): - Fix a bug in parsing that could cause clients to read a single byte past the end of an allocated region. This bug could be used to cause hardened clients (built with --enable-expensive-hardening) to crash if they tried to visit a hostile hidden service. Non- hardened clients are only affected depending on the details of their platform's memory allocator. Fixes bug 21018; bugfix on 0.2.0.8-alpha. Found by using libFuzzer. Also tracked as TROVE- 2016-12-002 and as CVE-2016-1254. o Major bugfixes (security, client, DNS proxy, backport from 0.2.8.3-alpha): - Stop a crash that could occur when a client running with DNSPort received a query with multiple address types, and the first address type was not supported. Found and fixed by Scott Dial. Fixes bug 18710; bugfix on 0.2.5.4-alpha. o Major bugfixes (security, correctness, backport from 0.2.7.4-rc): - Fix an error that could cause us to read 4 bytes before the beginning of an openssl string. This bug could be used to cause Tor to crash on systems with unusual malloc implementations, or systems with unusual hardening installed. Fixes bug 17404; bugfix on 0.2.3.6-alpha. o Major bugfixes (security, pointers, backport from 0.2.8.2-alpha): - Avoid a difficult-to-trigger heap corruption attack when extending a smartlist to contain over 16GB of pointers. Fixes bug 18162; bugfix on 0.1.1.11-alpha, which fixed a related bug incompletely. Reported by Guido Vranken. o Major bugfixes (dns proxy mode, crash, backport from 0.2.8.2-alpha): - Avoid crashing when running as a DNS proxy. Fixes bug 16248; bugfix on 0.2.0.1-alpha. Patch from "cypherpunks". o Major bugfixes (guard selection, backport from 0.2.7.6): - Actually look at the Guard flag when selecting a new directory guard. When we implemented the directory guard design, we accidentally started treating all relays as if they have the Guard flag during guard selection, leading to weaker anonymity and worse performance. Fixes bug 17772; bugfix on 0.2.4.8-alpha. Discovered by Mohsen Imani. o Major bugfixes (key management, backport from 0.2.8.3-alpha): - If OpenSSL fails to generate an RSA key, do not retain a dangling pointer to the previous (uninitialized) key value. The impact here should be limited to a difficult-to-trigger crash, if OpenSSL is running an engine that makes key generation failures possible, or if OpenSSL runs out of memory. Fixes bug 19152; bugfix on 0.2.1.10-alpha. Found by Yuan Jochen Kang, Suman Jana, and Baishakhi Ray. o Major bugfixes (parsing, backported from 0.3.0.4-rc): - Fix an integer underflow bug when comparing malformed Tor versions. This bug could crash Tor when built with --enable-expensive-hardening, or on Tor 0.2.9.1-alpha through Tor 0.2.9.8, which were built with -ftrapv by default. In other cases it was harmless. Part of TROVE-2017-001. Fixes bug 21278; bugfix on 0.0.8pre1. Found by OSS-Fuzz. o Minor features (security, memory erasure, backport from 0.2.8.1-alpha): - Make memwipe() do nothing when passed a NULL pointer or buffer of zero size. Check size argument to memwipe() for underflow. Fixes bug 18089; bugfix on 0.2.3.25 and 0.2.4.6-alpha. Reported by "gk", patch by "teor". o Minor features (bug-resistance, backport from 0.2.8.2-alpha): - Make Tor survive errors involving connections without a corresponding event object. Previously we'd fail with an assertion; now we produce a log message. Related to bug 16248. o Minor features (geoip): - Update geoip and geoip6 to the February 8 2017 Maxmind GeoLite2 Country database. o Minor bugfixes (compilation, backport from 0.2.7.6): - Fix a compilation warning with Clang 3.6: Do not check the presence of an address which can never be NULL. Fixes bug 17781. o Minor bugfixes (crypto error-handling, backport from 0.2.7.2-alpha): - Check for failures from crypto_early_init, and refuse to continue. A previous typo meant that we could keep going with an uninitialized crypto library, and would have OpenSSL initialize its own PRNG. Fixes bug 16360; bugfix on 0.2.5.2-alpha, introduced when implementing ticket 4900. Patch by "teor". o Minor bugfixes (hidden service, backport from 0.2.7.1-alpha): - Fix an out-of-bounds read when parsing invalid INTRODUCE2 cells on a client authorized hidden service. Fixes bug 15823; bugfix on 0.2.1.6-alpha. Changes in version 0.2.4.28 - 2017-03-03 Tor 0.2.4.28 backports a number of security fixes from later Tor releases. Anybody running Tor 0.2.4.27 or earlier should upgrade to this release, if for some reason they cannot upgrade to a later release series. Note that support for Tor 0.2.4.x is ending soon: we will not issue any fixes for the Tor 0.2.4.x series after 1 August 2017. If you need a Tor release series with long-term support, we recommend Tor 0.2.9.x. o Directory authority changes (backport from 0.2.8.5-rc): - Urras is no longer a directory authority. Closes ticket 19271. o Directory authority changes (backport from 0.2.9.2-alpha): - The "Tonga" bridge authority has been retired; the new bridge authority is "Bifroest". Closes tickets 19728 and 19690. o Directory authority key updates (backport from 0.2.8.1-alpha): - Update the V3 identity key for the dannenberg directory authority: it was changed on 18 November 2015. Closes task 17906. Patch by "teor". o Major features (security fixes, backport from 0.2.9.4-alpha): - Prevent a class of security bugs caused by treating the contents of a buffer chunk as if they were a NUL-terminated string. At least one such bug seems to be present in all currently used versions of Tor, and would allow an attacker to remotely crash most Tor instances, especially those compiled with extra compiler hardening. With this defense in place, such bugs can't crash Tor, though we should still fix them as they occur. Closes ticket 20384 (TROVE-2016-10-001). o Major bugfixes (parsing, security, backport from 0.2.9.8): - Fix a bug in parsing that could cause clients to read a single byte past the end of an allocated region. This bug could be used to cause hardened clients (built with --enable-expensive-hardening) to crash if they tried to visit a hostile hidden service. Non- hardened clients are only affected depending on the details of their platform's memory allocator. Fixes bug 21018; bugfix on 0.2.0.8-alpha. Found by using libFuzzer. Also tracked as TROVE- 2016-12-002 and as CVE-2016-1254. o Major bugfixes (security, correctness, backport from 0.2.7.4-rc): - Fix an error that could cause us to read 4 bytes before the beginning of an openssl string. This bug could be used to cause Tor to crash on systems with unusual malloc implementations, or systems with unusual hardening installed. Fixes bug 17404; bugfix on 0.2.3.6-alpha. o Major bugfixes (security, pointers, backport from 0.2.8.2-alpha): - Avoid a difficult-to-trigger heap corruption attack when extending a smartlist to contain over 16GB of pointers. Fixes bug 18162; bugfix on 0.1.1.11-alpha, which fixed a related bug incompletely. Reported by Guido Vranken. o Major bugfixes (dns proxy mode, crash, backport from 0.2.8.2-alpha): - Avoid crashing when running as a DNS proxy. Fixes bug 16248; bugfix on 0.2.0.1-alpha. Patch from "cypherpunks". o Major bugfixes (guard selection, backport from 0.2.7.6): - Actually look at the Guard flag when selecting a new directory guard. When we implemented the directory guard design, we accidentally started treating all relays as if they have the Guard flag during guard selection, leading to weaker anonymity and worse performance. Fixes bug 17772; bugfix on 0.2.4.8-alpha. Discovered by Mohsen Imani. o Major bugfixes (key management, backport from 0.2.8.3-alpha): - If OpenSSL fails to generate an RSA key, do not retain a dangling pointer to the previous (uninitialized) key value. The impact here should be limited to a difficult-to-trigger crash, if OpenSSL is running an engine that makes key generation failures possible, or if OpenSSL runs out of memory. Fixes bug 19152; bugfix on 0.2.1.10-alpha. Found by Yuan Jochen Kang, Suman Jana, and Baishakhi Ray. o Major bugfixes (parsing, backported from 0.3.0.4-rc): - Fix an integer underflow bug when comparing malformed Tor versions. This bug could crash Tor when built with --enable-expensive-hardening, or on Tor 0.2.9.1-alpha through Tor 0.2.9.8, which were built with -ftrapv by default. In other cases it was harmless. Part of TROVE-2017-001. Fixes bug 21278; bugfix on 0.0.8pre1. Found by OSS-Fuzz. o Minor features (security, memory erasure, backport from 0.2.8.1-alpha): - Make memwipe() do nothing when passed a NULL pointer or buffer of zero size. Check size argument to memwipe() for underflow. Fixes bug 18089; bugfix on 0.2.3.25 and 0.2.4.6-alpha. Reported by "gk", patch by "teor". o Minor features (bug-resistance, backport from 0.2.8.2-alpha): - Make Tor survive errors involving connections without a corresponding event object. Previously we'd fail with an assertion; now we produce a log message. Related to bug 16248. o Minor features (DoS-resistance, backport from 0.2.7.1-alpha): - Make it harder for attackers to overload hidden services with introductions, by blocking multiple introduction requests on the same circuit. Resolves ticket 15515. o Minor features (geoip): - Update geoip and geoip6 to the February 8 2017 Maxmind GeoLite2 Country database. o Minor bugfixes (compilation, backport from 0.2.7.6): - Fix a compilation warning with Clang 3.6: Do not check the presence of an address which can never be NULL. Fixes bug 17781. o Minor bugfixes (hidden service, backport from 0.2.7.1-alpha): - Fix an out-of-bounds read when parsing invalid INTRODUCE2 cells on a client authorized hidden service. Fixes bug 15823; bugfix on 0.2.1.6-alpha. Changes in version 0.3.0.4-rc - 2017-03-01 Tor 0.3.0.4-rc fixes some remaining bugs, large and small, in the 0.3.0 release series, and introduces a few reliability features to keep them from coming back. This is the first release candidate in the Tor 0.3.0 series. If we find no new bugs or regressions here, the first stable 0.3.0 release will be nearly identical to it. o Major bugfixes (bridges): - When the same bridge is configured multiple times with the same identity, but at different address:port combinations, treat those bridge instances as separate guards. This fix restores the ability of clients to configure the same bridge with multiple pluggable transports. Fixes bug 21027; bugfix on 0.3.0.1-alpha. o Major bugfixes (hidden service directory v3): - Stop crashing on a failed v3 hidden service descriptor lookup failure. Fixes bug 21471; bugfixes on 0.3.0.1-alpha. o Major bugfixes (parsing): - When parsing a malformed content-length field from an HTTP message, do not read off the end of the buffer. This bug was a potential remote denial-of-service attack against Tor clients and relays. A workaround was released in October 2016, to prevent this bug from crashing Tor. This is a fix for the underlying issue, which should no longer matter (if you applied the earlier patch). Fixes bug 20894; bugfix on 0.2.0.16-alpha. Bug found by fuzzing using AFL (http://lcamtuf.coredump.cx/afl/). - Fix an integer underflow bug when comparing malformed Tor versions. This bug could crash Tor when built with --enable-expensive-hardening, or on Tor 0.2.9.1-alpha through Tor 0.2.9.8, which were built with -ftrapv by default. In other cases it was harmless. Part of TROVE-2017-001. Fixes bug 21278; bugfix on 0.0.8pre1. Found by OSS-Fuzz. o Minor feature (protocol versioning): - Add new protocol version for proposal 224. HSIntro now advertises version "3-4" and HSDir version "1-2". Fixes ticket 20656. o Minor features (directory authorities): - Directory authorities now reject descriptors that claim to be malformed versions of Tor. Helps prevent exploitation of bug 21278. - Reject version numbers with components that exceed INT32_MAX. Otherwise 32-bit and 64-bit platforms would behave inconsistently. Fixes bug 21450; bugfix on 0.0.8pre1. - Directory authorities now reject relays running versions 0.2.9.1-alpha through 0.2.9.4-alpha, because those relays suffer from bug 20499 and don't keep their consensus cache up-to-date. Resolves ticket 20509. o Minor features (geoip): - Update geoip and geoip6 to the February 8 2017 Maxmind GeoLite2 Country database. o Minor features (reliability, crash): - Try better to detect problems in buffers where they might grow (or think they have grown) over 2 GB in size. Diagnostic for bug 21369. o Minor features (testing): - During 'make test-network-all', if tor logs any warnings, ask chutney to output them. Requires a recent version of chutney with the 21572 patch. Implements 21570. o Minor bugfixes (certificate expiration time): - Avoid using link certificates that don't become valid till some time in the future. Fixes bug 21420; bugfix on 0.2.4.11-alpha o Minor bugfixes (code correctness): - Repair a couple of (unreachable or harmless) cases of the risky comparison-by-subtraction pattern that caused bug 21278. - Remove a redundant check for the UseEntryGuards option from the options_transition_affects_guards() function. Fixes bug 21492; bugfix on 0.3.0.1-alpha. o Minor bugfixes (directory mirrors): - Allow relays to use directory mirrors without a DirPort: these relays need to be contacted over their ORPorts using a begindir connection. Fixes one case of bug 20711; bugfix on 0.2.8.2-alpha. - Clarify the message logged when a remote relay is unexpectedly missing an ORPort or DirPort: users were confusing this with a local port. Fixes another case of bug 20711; bugfix on 0.2.8.2-alpha. o Minor bugfixes (guards): - Don't warn about a missing guard state on timeout-measurement circuits: they aren't supposed to be using guards. Fixes an instance of bug 21007; bugfix on 0.3.0.1-alpha. - Silence a BUG() warning when attempting to use a guard whose descriptor we don't know, and make this scenario less likely to happen. Fixes bug 21415; bugfix on 0.3.0.1-alpha. o Minor bugfixes (hidden service): - Pass correct buffer length when encoding legacy ESTABLISH_INTRO cells. Previously, we were using sizeof() on a pointer, instead of the real destination buffer. Fortunately, that value was only used to double-check that there was enough room--which was already enforced elsewhere. Fixes bug 21553; bugfix on 0.3.0.1-alpha. o Minor bugfixes (testing): - Fix Raspbian build issues related to missing socket errno in test_util.c. Fixes bug 21116; bugfix on 0.2.8.2. Patch by "hein". - Rename "make fuzz" to "make test-fuzz-corpora", since it doesn't actually fuzz anything. Fixes bug 21447; bugfix on 0.3.0.3-alpha. - Use bash in src/test/test-network.sh. This ensures we reliably call chutney's newer tools/test-network.sh when available. Fixes bug 21562; bugfix on 0.2.9.1-alpha. o Documentation: - Small fixes to the fuzzing documentation. Closes ticket 21472. Changes in version 0.2.9.10 - 2017-03-01 Tor 0.2.9.10 backports a security fix from later Tor release. It also includes fixes for some major issues affecting directory authorities, LibreSSL compatibility, and IPv6 correctness. The Tor 0.2.9.x release series is now marked as a long-term-support series. We intend to backport security fixes to 0.2.9.x until at least January of 2020. o Major bugfixes (directory authority, 0.3.0.3-alpha): - During voting, when marking a relay as a probable sybil, do not clear its BadExit flag: sybils can still be bad in other ways too. (We still clear the other flags.) Fixes bug 21108; bugfix on 0.2.0.13-alpha. o Major bugfixes (IPv6 Exits, backport from 0.3.0.3-alpha): - Stop rejecting all IPv6 traffic on Exits whose exit policy rejects any IPv6 addresses. Instead, only reject a port over IPv6 if the exit policy rejects that port on more than an IPv6 /16 of addresses. This bug was made worse by 17027 in 0.2.8.1-alpha, which rejected a relay's own IPv6 address by default. Fixes bug 21357; bugfix on commit 004f3f4e53 in 0.2.4.7-alpha. o Major bugfixes (parsing, also in 0.3.0.4-rc): - Fix an integer underflow bug when comparing malformed Tor versions. This bug could crash Tor when built with --enable-expensive-hardening, or on Tor 0.2.9.1-alpha through Tor 0.2.9.8, which were built with -ftrapv by default. In other cases it was harmless. Part of TROVE-2017-001. Fixes bug 21278; bugfix on 0.0.8pre1. Found by OSS-Fuzz. o Minor features (directory authorities, also in 0.3.0.4-rc): - Directory authorities now reject descriptors that claim to be malformed versions of Tor. Helps prevent exploitation of bug 21278. - Reject version numbers with components that exceed INT32_MAX. Otherwise 32-bit and 64-bit platforms would behave inconsistently. Fixes bug 21450; bugfix on 0.0.8pre1. o Minor features (geoip): - Update geoip and geoip6 to the February 8 2017 Maxmind GeoLite2 Country database. o Minor features (portability, compilation, backport from 0.3.0.3-alpha): - Autoconf now checks to determine if OpenSSL structures are opaque, instead of explicitly checking for OpenSSL version numbers. Part of ticket 21359. - Support building with recent LibreSSL code that uses opaque structures. Closes ticket 21359. o Minor bugfixes (code correctness, also in 0.3.0.4-rc): - Repair a couple of (unreachable or harmless) cases of the risky comparison-by-subtraction pattern that caused bug 21278. o Minor bugfixes (tor-resolve, backport from 0.3.0.3-alpha): - The tor-resolve command line tool now rejects hostnames over 255 characters in length. Previously, it would silently truncate them, which could lead to bugs. Fixes bug 21280; bugfix on 0.0.9pre5. Patch by "junglefowl". Changes in version 0.3.0.3-alpha - 2017-02-03 Tor 0.3.0.3-alpha fixes a few significant bugs introduced over the 0.3.0.x development series, including some that could cause authorities to behave badly. There is also a fix for a longstanding bug that could prevent IPv6 exits from working. Tor 0.3.0.3-alpha also includes some smaller features and bugfixes. The Tor 0.3.0.x release series is now in patch-freeze: no additional features will be considered for inclusion in 0.3.0.x. We suspect that some bugs will probably remain, however, and we encourage people to test this release. o Major bugfixes (directory authority): - During voting, when marking a relay as a probable sybil, do not clear its BadExit flag: sybils can still be bad in other ways too. (We still clear the other flags.) Fixes bug 21108; bugfix on 0.2.0.13-alpha. - When deciding whether we have just found a router to be reachable, do not penalize it for not having performed an Ed25519 link handshake if it does not claim to support an Ed25519 handshake. Previously, we would treat such relays as non-running. Fixes bug 21107; bugfix on 0.3.0.1-alpha. o Major bugfixes (entry guards): - Stop trying to build circuits through entry guards for which we have no descriptor. Also, stop crashing in the case that we *do* accidentally try to build a circuit in such a state. Fixes bug 21242; bugfix on 0.3.0.1-alpha. o Major bugfixes (IPv6 Exits): - Stop rejecting all IPv6 traffic on Exits whose exit policy rejects any IPv6 addresses. Instead, only reject a port over IPv6 if the exit policy rejects that port on more than an IPv6 /16 of addresses. This bug was made worse by 17027 in 0.2.8.1-alpha, which rejected a relay's own IPv6 address by default. Fixes bug 21357; bugfix on commit 004f3f4e53 in 0.2.4.7-alpha. o Minor feature (client): - Enable IPv6 traffic on the SocksPort by default. To disable this, a user will have to specify "NoIPv6Traffic". Closes ticket 21269. o Minor feature (fallback scripts): - Add a check_existing mode to updateFallbackDirs.py, which checks if fallbacks in the hard-coded list are working. Closes ticket 20174. Patch by haxxpop. o Minor features (ciphersuite selection): - Clients now advertise a list of ciphersuites closer to the ones preferred by Firefox. Closes part of ticket 15426. - Allow relays to accept a wider range of ciphersuites, including chacha20-poly1305 and AES-CCM. Closes the other part of 15426. o Minor features (controller, configuration): - Each of the *Port options, such as SocksPort, ORPort, ControlPort, and so on, now comes with a __*Port variant that will not be saved to the torrc file by the controller's SAVECONF command. This change allows TorBrowser to set up a single-use domain socket for each time it launches Tor. Closes ticket 20956. - The GETCONF command can now query options that may only be meaningful in context-sensitive lists. This allows the controller to query the mixed SocksPort/__SocksPort style options introduced in feature 20956. Implements ticket 21300. o Minor features (portability, compilation): - Autoconf now checks to determine if OpenSSL structures are opaque, instead of explicitly checking for OpenSSL version numbers. Part of ticket 21359. - Support building with recent LibreSSL code that uses opaque structures. Closes ticket 21359. o Minor features (relay): - We now allow separation of exit and relay traffic to different source IP addresses, using the OutboundBindAddressExit and OutboundBindAddressOR options respectively. Closes ticket 17975. Written by Michael Sonntag. o Minor bugfix (logging): - Don't recommend the use of Tor2web in non-anonymous mode. Recommending Tor2web is a bad idea because the client loses all anonymity. Tor2web should only be used in specific cases by users who *know* and understand the issues. Fixes bug 21294; bugfix on 0.2.9.3-alpha. o Minor bugfixes (client): - Always recover from failures in extend_info_from_node(), in an attempt to prevent any recurrence of bug 21242. Fixes bug 21372; bugfix on 0.2.3.1-alpha. o Minor bugfixes (client, entry guards): - Fix a bug warning (with backtrace) when we fail a channel that circuits to fallback directories on it. Fixes bug 21128; bugfix on 0.3.0.1-alpha. - Fix a spurious bug warning (with backtrace) when removing an expired entry guard. Fixes bug 21129; bugfix on 0.3.0.1-alpha. - Fix a bug of the new guard algorithm where tor could stall for up to 10 minutes before retrying a guard after a long period of no network. Fixes bug 21052; bugfix on 0.3.0.1-alpha. - Do not try to build circuits until we have descriptors for our primary entry guards. Related to fix for bug 21242. o Minor bugfixes (configure, autoconf): - Rename the configure option --enable-expensive-hardening to --enable-fragile-hardening. Expensive hardening makes the tor daemon abort when some kinds of issues are detected. Thus, it makes tor more at risk of remote crashes but safer against RCE or heartbleed bug category. We now try to explain this issue in a message from the configure script. Fixes bug 21290; bugfix on 0.2.5.4-alpha. o Minor bugfixes (controller): - Restore the (deprecated) DROPGUARDS controller command. Fixes bug 20824; bugfix on 0.3.0.1-alpha. o Minor bugfixes (hidden service): - Clean up the code for expiring intro points with no associated circuits. It was causing, rarely, a service with some expiring introduction points to not open enough additional introduction points. Fixes part of bug 21302; bugfix on 0.2.7.2-alpha. - Stop setting the torrc option HiddenServiceStatistics to "0" just because we're not a bridge or relay. Instead, we preserve whatever value the user set (or didn't set). Fixes bug 21150; bugfix on 0.2.6.2-alpha. - Resolve two possible underflows which could lead to creating and closing a lot of introduction point circuits in a non-stop loop. Fixes bug 21302; bugfix on 0.2.7.2-alpha. o Minor bugfixes (portability): - Use "OpenBSD" compiler macro instead of "OPENBSD" or "__OpenBSD__". It is supported by OpenBSD itself, and also by most OpenBSD variants (such as Bitrig). Fixes bug 20980; bugfix on 0.1.2.1-alpha. - When mapping a file of length greater than SIZE_MAX, do not silently truncate its contents. This issue could occur on 32 bit systems with large file support and files which are larger than 4 GB. Fixes bug 21134; bugfix on 0.3.0.1-alpha. o Minor bugfixes (tor-resolve): - The tor-resolve command line tool now rejects hostnames over 255 characters in length. Previously, it would silently truncate them, which could lead to bugs. Fixes bug 21280; bugfix on 0.0.9pre5. Patch by "junglefowl". o Minor bugfixes (Windows services): - Be sure to initialize the monotonic time subsystem before using it, even when running as an NT service. Fixes bug 21356; bugfix on 0.2.9.1-alpha. Changes in version 0.3.0.2-alpha - 2017-01-23 Tor 0.3.0.2-alpha fixes a denial-of-service bug where an attacker could cause relays and clients to crash, even if they were not built with the --enable-expensive-hardening option. This bug affects all 0.2.9.x versions, and also affects 0.3.0.1-alpha: all relays running an affected version should upgrade. Tor 0.3.0.2-alpha also improves how exit relays and clients handle DNS time-to-live values, makes directory authorities enforce the 1-to-1 mapping of relay RSA identity keys to ED25519 identity keys, fixes a client-side onion service reachability bug, does better at selecting the set of fallback directories, and more. o Major bugfixes (security, also in 0.2.9.9): - Downgrade the "-ftrapv" option from "always on" to "only on when --enable-expensive-hardening is provided." This hardening option, like others, can turn survivable bugs into crashes--and having it on by default made a (relatively harmless) integer overflow bug into a denial-of-service bug. Fixes bug 21278 (TROVE-2017-001); bugfix on 0.2.9.1-alpha. o Major features (security): - Change the algorithm used to decide DNS TTLs on client and server side, to better resist DNS-based correlation attacks like the DefecTor attack of Greschbach, Pulls, Roberts, Winter, and Feamster. Now relays only return one of two possible DNS TTL values, and clients are willing to believe DNS TTL values up to 3 hours long. Closes ticket 19769. o Major features (directory authority, security): - The default for AuthDirPinKeys is now 1: directory authorities will reject relays where the RSA identity key matches a previously seen value, but the Ed25519 key has changed. Closes ticket 18319. o Major bugfixes (client, guard, crash): - In circuit_get_global_origin_list(), return the actual list of origin circuits. The previous version of this code returned the list of all the circuits, and could have caused strange bugs, including possible crashes. Fixes bug 21118; bugfix on 0.3.0.1-alpha. o Major bugfixes (client, onion service, also in 0.2.9.9): - Fix a client-side onion service reachability bug, where multiple socks requests to an onion service (or a single slow request) could cause us to mistakenly mark some of the service's introduction points as failed, and we cache that failure so eventually we run out and can't reach the service. Also resolves a mysterious "Remote server sent bogus reason code 65021" log warning. The bug was introduced in ticket 17218, where we tried to remember the circuit end reason as a uint16_t, which mangled negative values. Partially fixes bug 21056 and fixes bug 20307; bugfix on 0.2.8.1-alpha. o Major bugfixes (DNS): - Fix a bug that prevented exit nodes from caching DNS records for more than 60 seconds. Fixes bug 19025; bugfix on 0.2.4.7-alpha. o Minor features (controller): - Add "GETINFO sr/current" and "GETINFO sr/previous" keys, to expose shared-random values to the controller. Closes ticket 19925. o Minor features (entry guards): - Add UseEntryGuards to TEST_OPTIONS_DEFAULT_VALUES in order to not break regression tests. - Require UseEntryGuards when UseBridges is set, in order to make sure bridges aren't bypassed. Resolves ticket 20502. o Minor features (fallback directories): - Select 200 fallback directories for each release. Closes ticket 20881. - Allow 3 fallback relays per operator, which is safe now that we are choosing 200 fallback relays. Closes ticket 20912. - Exclude relays affected by bug 20499 from the fallback list. Exclude relays from the fallback list if they are running versions known to be affected by bug 20499, or if in our tests they deliver a stale consensus (i.e. one that expired more than 24 hours ago). Closes ticket 20539. - Reduce the minimum fallback bandwidth to 1 MByte/s. Part of ticket 18828. - Require fallback directories to have the same address and port for 7 days (now that we have enough relays with this stability). Relays whose OnionOO stability timer is reset on restart by bug 18050 should upgrade to Tor 0.2.8.7 or later, which has a fix for this issue. Closes ticket 20880; maintains short-term fix in 0.2.8.2-alpha. - Require fallbacks to have flags for 90% of the time (weighted decaying average), rather than 95%. This allows at least 73% of clients to bootstrap in the first 5 seconds without contacting an authority. Part of ticket 18828. - Annotate updateFallbackDirs.py with the bandwidth and consensus weight for each candidate fallback. Closes ticket 20878. - Make it easier to change the output sort order of fallbacks. Closes ticket 20822. - Display the relay fingerprint when downloading consensuses from fallbacks. Closes ticket 20908. o Minor features (geoip, also in 0.2.9.9): - Update geoip and geoip6 to the January 4 2017 Maxmind GeoLite2 Country database. o Minor features (next-gen onion service directories): - Remove the "EnableOnionServicesV3" consensus parameter that we introduced in 0.3.0.1-alpha: relays are now always willing to act as v3 onion service directories. Resolves ticket 19899. o Minor features (linting): - Enhance the changes file linter to warn on Tor versions that are prefixed with "tor-". Closes ticket 21096. o Minor features (logging): - In several places, describe unset ed25519 keys as "", rather than the scary "AAAAAAAA...AAA". Closes ticket 21037. o Minor bugfix (control protocol): - The reply to a "GETINFO config/names" request via the control protocol now spells the type "Dependent" correctly. This is a breaking change in the control protocol. (The field seems to be ignored by the most common known controllers.) Fixes bug 18146; bugfix on 0.1.1.4-alpha. o Minor bugfixes (bug resilience): - Fix an unreachable size_t overflow in base64_decode(). Fixes bug 19222; bugfix on 0.2.0.9-alpha. Found by Guido Vranken; fixed by Hans Jerry Illikainen. o Minor bugfixes (build): - Replace obsolete Autoconf macros with their modern equivalent and prevent similar issues in the future. Fixes bug 20990; bugfix on 0.1.0.1-rc. o Minor bugfixes (client, guards): - Fix bug where Tor would think that there are circuits waiting for better guards even though those circuits have been freed. Fixes bug 21142; bugfix on 0.3.0.1-alpha. o Minor bugfixes (config): - Don't assert on startup when trying to get the options list and LearnCircuitBuildTimeout is set to 0: we are currently parsing the options so of course they aren't ready yet. Fixes bug 21062; bugfix on 0.2.9.3-alpha. o Minor bugfixes (controller): - Make the GETINFO interface for inquiring about entry guards support the new guards backend. Fixes bug 20823; bugfix on 0.3.0.1-alpha. o Minor bugfixes (dead code): - Remove a redundant check for PidFile changes at runtime in options_transition_allowed(): this check is already performed regardless of whether the sandbox is active. Fixes bug 21123; bugfix on 0.2.5.4-alpha. o Minor bugfixes (documentation): - Update the tor manual page to document every option that can not be changed while tor is running. Fixes bug 21122. o Minor bugfixes (fallback directories): - Stop failing when a relay has no uptime data in updateFallbackDirs.py. Fixes bug 20945; bugfix on 0.2.8.1-alpha. - Avoid checking fallback candidates' DirPorts if they are down in OnionOO. When a relay operator has multiple relays, this prioritizes relays that are up over relays that are down. Fixes bug 20926; bugfix on 0.2.8.3-alpha. - Stop failing when OUTPUT_COMMENTS is True in updateFallbackDirs.py. Fixes bug 20877; bugfix on 0.2.8.3-alpha. o Minor bugfixes (guards, bootstrapping): - When connecting to a directory guard during bootstrap, do not mark the guard as successful until we receive a good-looking directory response from it. Fixes bug 20974; bugfix on 0.3.0.1-alpha. o Minor bugfixes (onion services): - Fix the config reload pruning of old vs new services so it actually works when both ephemeral and non-ephemeral services are configured. Fixes bug 21054; bugfix on 0.3.0.1-alpha. - Allow the number of introduction points to be as low as 0, rather than as low as 3. Fixes bug 21033; bugfix on 0.2.7.2-alpha. o Minor bugfixes (IPv6): - Make IPv6-using clients try harder to find an IPv6 directory server. Fixes bug 20999; bugfix on 0.2.8.2-alpha. - When IPv6 addresses have not been downloaded yet (microdesc consensus documents don't list relay IPv6 addresses), use hard- coded addresses for authorities, fallbacks, and configured bridges. Now IPv6-only clients can use microdescriptors. Fixes bug 20996; bugfix on b167e82 from 19608 in 0.2.8.5-alpha. o Minor bugfixes (memory leaks): - Fix a memory leak when configuring hidden services. Fixes bug 20987; bugfix on 0.3.0.1-alpha. o Minor bugfixes (portability, also in 0.2.9.9): - Avoid crashing when Tor is built using headers that contain CLOCK_MONOTONIC_COARSE, but then tries to run on an older kernel without CLOCK_MONOTONIC_COARSE. Fixes bug 21035; bugfix on 0.2.9.1-alpha. - Fix Libevent detection on platforms without Libevent 1 headers installed. Fixes bug 21051; bugfix on 0.2.9.1-alpha. o Minor bugfixes (relay): - Honor DataDirectoryGroupReadable when tor is a relay. Previously, initializing the keys would reset the DataDirectory to 0700 instead of 0750 even if DataDirectoryGroupReadable was set to 1. Fixes bug 19953; bugfix on 0.0.2pre16. Patch by "redfish". o Minor bugfixes (testing): - Remove undefined behavior from the backtrace generator by removing its signal handler. Fixes bug 21026; bugfix on 0.2.5.2-alpha. o Minor bugfixes (unit tests): - Allow the unit tests to pass even when DNS lookups of bogus addresses do not fail as expected. Fixes bug 20862 and 20863; bugfix on unit tests introduced in 0.2.8.1-alpha through 0.2.9.4-alpha. o Code simplification and refactoring: - Refactor code to manipulate global_origin_circuit_list into separate functions. Closes ticket 20921. o Documentation (formatting): - Clean up formatting of tor.1 man page and HTML doc, where 
      blocks were incorrectly appearing. Closes ticket 20885.

  o Documentation (man page):
    - Clarify many options in tor.1 and add some min/max values for
      HiddenService options. Closes ticket 21058.


Changes in version 0.2.9.9 - 2017-01-23
  Tor 0.2.9.9 fixes a denial-of-service bug where an attacker could
  cause relays and clients to crash, even if they were not built with
  the --enable-expensive-hardening option. This bug affects all 0.2.9.x
  versions, and also affects 0.3.0.1-alpha: all relays running an affected
  version should upgrade.

  This release also resolves a client-side onion service reachability
  bug, and resolves a pair of small portability issues.

  o Major bugfixes (security):
    - Downgrade the "-ftrapv" option from "always on" to "only on when
      --enable-expensive-hardening is provided." This hardening option,
      like others, can turn survivable bugs into crashes -- and having
      it on by default made a (relatively harmless) integer overflow bug
      into a denial-of-service bug. Fixes bug 21278 (TROVE-2017-001);
      bugfix on 0.2.9.1-alpha.

  o Major bugfixes (client, onion service):
    - Fix a client-side onion service reachability bug, where multiple
      socks requests to an onion service (or a single slow request)
      could cause us to mistakenly mark some of the service's
      introduction points as failed, and we cache that failure so
      eventually we run out and can't reach the service. Also resolves a
      mysterious "Remote server sent bogus reason code 65021" log
      warning. The bug was introduced in ticket 17218, where we tried to
      remember the circuit end reason as a uint16_t, which mangled
      negative values. Partially fixes bug 21056 and fixes bug 20307;
      bugfix on 0.2.8.1-alpha.

  o Minor features (geoip):
    - Update geoip and geoip6 to the January 4 2017 Maxmind GeoLite2
      Country database.

  o Minor bugfixes (portability):
    - Avoid crashing when Tor is built using headers that contain
      CLOCK_MONOTONIC_COARSE, but then tries to run on an older kernel
      without CLOCK_MONOTONIC_COARSE. Fixes bug 21035; bugfix
      on 0.2.9.1-alpha.
    - Fix Libevent detection on platforms without Libevent 1 headers
      installed. Fixes bug 21051; bugfix on 0.2.9.1-alpha.


Changes in version 0.3.0.1-alpha - 2016-12-19
  Tor 0.3.0.1-alpha is the first alpha release in the 0.3.0 development
  series. It strengthens Tor's link and circuit handshakes by
  identifying relays by their Ed25519 keys, improves the algorithm that
  clients use to choose and maintain their list of guards, and includes
  additional backend support for the next-generation hidden service
  design. It also contains numerous other small features and
  improvements to security, correctness, and performance.

  Below are the changes since 0.2.9.8.

  o Major features (guard selection algorithm):
    - Tor's guard selection algorithm has been redesigned from the
      ground up, to better support unreliable networks and restrictive
      sets of entry nodes, and to better resist guard-capture attacks by
      hostile local networks. Implements proposal 271; closes
      ticket 19877.

  o Major features (next-generation hidden services):
    - Relays can now handle v3 ESTABLISH_INTRO cells as specified by
      prop224 aka "Next Generation Hidden Services". Service and clients
      don't use this functionality yet. Closes ticket 19043. Based on
      initial code by Alec Heifetz.
    - Relays now support the HSDir version 3 protocol, so that they can
      can store and serve v3 descriptors. This is part of the next-
      generation onion service work detailed in proposal 224. Closes
      ticket 17238.

  o Major features (protocol, ed25519 identity keys):
    - Relays now use Ed25519 to prove their Ed25519 identities and to
      one another, and to clients. This algorithm is faster and more
      secure than the RSA-based handshake we've been doing until now.
      Implements the second big part of proposal 220; Closes
      ticket 15055.
    - Clients now support including Ed25519 identity keys in the EXTEND2
      cells they generate. By default, this is controlled by a consensus
      parameter, currently disabled. You can turn this feature on for
      testing by setting ExtendByEd25519ID in your configuration. This
      might make your traffic appear different than the traffic
      generated by other users, however. Implements part of ticket
      15056; part of proposal 220.
    - Relays now understand requests to extend to other relays by their
      Ed25519 identity keys. When an Ed25519 identity key is included in
      an EXTEND2 cell, the relay will only extend the circuit if the
      other relay can prove ownership of that identity. Implements part
      of ticket 15056; part of proposal 220.

  o Major bugfixes (scheduler):
    - Actually compare circuit policies in ewma_cmp_cmux(). This bug
      caused the channel scheduler to behave more or less randomly,
      rather than preferring channels with higher-priority circuits.
      Fixes bug 20459; bugfix on 0.2.6.2-alpha.

  o Minor features (controller):
    - When HSFETCH arguments cannot be parsed, say "Invalid argument"
      rather than "unrecognized." Closes ticket 20389; patch from
      Ivan Markin.

  o Minor features (diagnostic, directory client):
    - Warn when we find an unexpected inconsistency in directory
      download status objects. Prevents some negative consequences of
      bug 20593.

  o Minor features (directory authority):
    - Add a new authority-only AuthDirTestEd25519LinkKeys option (on by
      default) to control whether authorities should try to probe relays
      by their Ed25519 link keys. This option will go away in a few
      releases--unless we encounter major trouble in our ed25519 link
      protocol rollout, in which case it will serve as a safety option.

  o Minor features (directory cache):
    - Relays and bridges will now refuse to serve the consensus they
      have if they know it is too old for a client to use. Closes
      ticket 20511.

  o Minor features (ed25519 link handshake):
    - Advertise support for the ed25519 link handshake using the
      subprotocol-versions mechanism, so that clients can tell which
      relays can identity themselves by Ed25519 ID. Closes ticket 20552.

  o Minor features (fingerprinting resistance, authentication):
    - Extend the length of RSA keys used for TLS link authentication to
      2048 bits. (These weren't used for forward secrecy; for forward
      secrecy, we used P256.) Closes ticket 13752.

  o Minor features (infrastructure):
    - Implement smartlist_add_strdup() function. Replaces the use of
      smartlist_add(sl, tor_strdup(str)). Closes ticket 20048.

  o Minor bugfixes (client):
    - When clients that use bridges start up with a cached consensus on
      disk, they were ignoring it and downloading a new one. Now they
      use the cached one. Fixes bug 20269; bugfix on 0.2.3.12-alpha.

  o Minor bugfixes (configuration):
    - Accept non-space whitespace characters after the severity level in
      the `Log` option. Fixes bug 19965; bugfix on 0.2.1.1-alpha.
    - Support "TByte" and "TBytes" units in options given in bytes.
      "TB", "terabyte(s)", "TBit(s)" and "terabit(s)" were already
      supported. Fixes bug 20622; bugfix on 0.2.0.14-alpha.

  o Minor bugfixes (consensus weight):
    - Add new consensus method that initializes bw weights to 1 instead
      of 0. This prevents a zero weight from making it all the way to
      the end (happens in small testing networks) and causing an error.
      Fixes bug 14881; bugfix on 0.2.2.17-alpha.

  o Minor bugfixes (descriptors):
    - Correctly recognise downloaded full descriptors as valid, even
      when using microdescriptors as circuits. This affects clients with
      FetchUselessDescriptors set, and may affect directory authorities.
      Fixes bug 20839; bugfix on 0.2.3.2-alpha.

  o Minor bugfixes (directory system):
    - Download all consensus flavors, descriptors, and authority
      certificates when FetchUselessDescriptors is set, regardless of
      whether tor is a directory cache or not. Fixes bug 20667; bugfix
      on all recent tor versions.
    - Bridges and relays now use microdescriptors (like clients do)
      rather than old-style router descriptors. Now bridges will blend
      in with clients in terms of the circuits they build. Fixes bug
      6769; bugfix on 0.2.3.2-alpha.

  o Minor bugfixes (ed25519 certificates):
    - Correctly interpret ed25519 certificates that would expire some
      time after 19 Jan 2038. Fixes bug 20027; bugfix on 0.2.7.2-alpha.

  o Minor bugfixes (hidden services):
    - Stop ignoring misconfigured hidden services. Instead, refuse to
      start tor until the misconfigurations have been corrected. Fixes
      bug 20559; bugfix on multiple commits in 0.2.7.1-alpha
      and earlier.

  o Minor bugfixes (memory leak at exit):
    - Fix a small harmless memory leak at exit of the previously unused
      RSA->Ed identity cross-certificate. Fixes bug 17779; bugfix
      on 0.2.7.2-alpha.

  o Minor bugfixes (util):
    - When finishing writing a file to disk, if we were about to replace
      the file with the temporary file created before and we fail to
      replace it, remove the temporary file so it doesn't stay on disk.
      Fixes bug 20646; bugfix on 0.2.0.7-alpha. Patch by fk.

  o Minor bugfixes (Windows):
    - Check for getpagesize before using it to mmap files. This fixes
      compilation in some MinGW environments. Fixes bug 20530; bugfix on
      0.1.2.1-alpha. Reported by "ice".

  o Code simplification and refactoring:
    - Abolish all global guard context in entrynodes.c; replace with new
      guard_selection_t structure as preparation for proposal 271.
      Closes ticket 19858.
    - Introduce rend_service_is_ephemeral() that tells if given onion
      service is ephemeral. Replace unclear NULL-checkings for service
      directory with this function. Closes ticket 20526.
    - Extract magic numbers in circuituse.c into defined variables.
    - Refactor circuit_is_available_for_use to remove unnecessary check.
    - Refactor circuit_predict_and_launch_new for readability and
      testability. Closes ticket 18873.
    - Refactor large if statement in purpose_needs_anonymity to use
      switch statement instead. Closes part of ticket 20077.
    - Refactor the hashing API to return negative values for errors, as
      is done as throughout the codebase. Closes ticket 20717.
    - Remove data structures that were used to index or_connection
      objects by their RSA identity digests. These structures are fully
      redundant with the similar structures used in the
      channel abstraction.
    - Remove duplicate code in the channel_write_*cell() functions.
      Closes ticket 13827; patch from Pingl.
    - Remove redundant behavior of is_sensitive_dir_purpose, refactor to
      use only purpose_needs_anonymity. Closes part of ticket 20077.
    - The code to generate and parse EXTEND and EXTEND2 cells has been
      replaced with code automatically generated by the
      "trunnel" utility.

  o Documentation:
    - Include the "TBits" unit in Tor's man page. Fixes part of bug
      20622; bugfix on 0.2.5.1-alpha.
    - Change '1' to 'weight_scale' in consensus bw weights calculation
      comments, as that is reality. Closes ticket 20273. Patch
      from pastly.
    - Correct the value for AuthDirGuardBWGuarantee in the manpage, from
      250 KBytes to 2 MBytes. Fixes bug 20435; bugfix
      on 0.2.5.6-alpha.
    - Stop the man page from incorrectly stating that HiddenServiceDir
      must already exist. Fixes 20486.
    - Clarify that when ClientRejectInternalAddresses is enabled (which
      is the default), multicast DNS hostnames for machines on the local
      network (of the form *.local) are also rejected. Closes
      ticket 17070.

  o Removed features:
    - The AuthDirMaxServersPerAuthAddr option no longer exists: The same
      limit for relays running on a single IP applies to authority IP
      addresses as well as to non-authority IP addresses. Closes
      ticket 20960.
    - The UseDirectoryGuards torrc option no longer exists: all users
      that use entry guards will also use directory guards. Related to
      proposal 271; implements part of ticket 20831.

  o Testing:
    - New unit tests for tor_htonll(). Closes ticket 19563. Patch
      from "overcaffeinated".
    - Perform the coding style checks when running the tests and fail
      when coding style violations are found. Closes ticket 5500.
    - Add tests for networkstatus_compute_bw_weights_v10.
    - Add unit tests circuit_predict_and_launch_new.
    - Extract dummy_origin_circuit_new so it can be used by other
      test functions.


Changes in version 0.2.8.12 - 2016-12-19
  Tor 0.2.8.12 backports a fix for a medium-severity issue (bug 21018
  below) where Tor clients could crash when attempting to visit a
  hostile hidden service. Clients are recommended to upgrade as packages
  become available for their systems.

  It also includes an updated list of fallback directories, backported
  from 0.2.9.

  Now that the Tor 0.2.9 series is stable, only major bugfixes will be
  backported to 0.2.8 in the future.

  o Major bugfixes (parsing, security, backported from 0.2.9.8):
    - Fix a bug in parsing that could cause clients to read a single
      byte past the end of an allocated region. This bug could be used
      to cause hardened clients (built with --enable-expensive-hardening)
      to crash if they tried to visit a hostile hidden service. Non-
      hardened clients are only affected depending on the details of
      their platform's memory allocator. Fixes bug 21018; bugfix on
      0.2.0.8-alpha. Found by using libFuzzer. Also tracked as TROVE-
      2016-12-002 and as CVE-2016-1254.

  o Minor features (fallback directory list, backported from 0.2.9.8):
    - Replace the 81 remaining fallbacks of the 100 originally
      introduced in Tor 0.2.8.3-alpha in March 2016, with a list of 177
      fallbacks (123 new, 54 existing, 27 removed) generated in December
      2016. Resolves ticket 20170.

  o Minor features (geoip, backported from 0.2.9.7-rc):
    - Update geoip and geoip6 to the December 7 2016 Maxmind GeoLite2
      Country database.


Changes in version 0.2.9.8 - 2016-12-19
  Tor 0.2.9.8 is the first stable release of the Tor 0.2.9 series.

  The Tor 0.2.9 series makes mandatory a number of security features
  that were formerly optional. It includes support for a new shared-
  randomness protocol that will form the basis for next generation
  hidden services, includes a single-hop hidden service mode for
  optimizing .onion services that don't actually want to be hidden,
  tries harder not to overload the directory authorities with excessive
  downloads, and supports a better protocol versioning scheme for
  improved compatibility with other implementations of the Tor protocol.

  And of course, there are numerous other bugfixes and improvements.

  This release also includes a fix for a medium-severity issue (bug
  21018 below) where Tor clients could crash when attempting to visit a
  hostile hidden service. Clients are recommended to upgrade as packages
  become available for their systems.

  Below are the changes since 0.2.9.7-rc. For a list of all changes
  since 0.2.8, see the ReleaseNotes file.

  o Major bugfixes (parsing, security):
    - Fix a bug in parsing that could cause clients to read a single
      byte past the end of an allocated region. This bug could be used
      to cause hardened clients (built with --enable-expensive-hardening)
      to crash if they tried to visit a hostile hidden service. Non-
      hardened clients are only affected depending on the details of
      their platform's memory allocator. Fixes bug 21018; bugfix on
      0.2.0.8-alpha. Found by using libFuzzer. Also tracked as TROVE-
      2016-12-002 and as CVE-2016-1254.

  o Minor features (fallback directory list):
    - Replace the 81 remaining fallbacks of the 100 originally
      introduced in Tor 0.2.8.3-alpha in March 2016, with a list of 177
      fallbacks (123 new, 54 existing, 27 removed) generated in December
      2016. Resolves ticket 20170.


Changes in version 0.2.9.7-rc - 2016-12-12
  Tor 0.2.9.7-rc fixes a few small bugs remaining in Tor 0.2.9.6-rc,
  including a few that had prevented tests from passing on
  some platforms.

  o Minor features (geoip):
    - Update geoip and geoip6 to the December 7 2016 Maxmind GeoLite2
      Country database.

  o Minor bugfix (build):
    - The current Git revision when building from a local repository is
      now detected correctly when using git worktrees. Fixes bug 20492;
      bugfix on 0.2.3.9-alpha.

  o Minor bugfixes (directory authority):
    - When computing old Tor protocol line version in protover, we were
      looking at 0.2.7.5 twice instead of a specific case for
      0.2.9.1-alpha. Fixes bug 20810; bugfix on 0.2.9.4-alpha.

  o Minor bugfixes (download scheduling):
    - Resolve a "bug" warning when considering a download schedule whose
      delay had approached INT_MAX. Fixes 20875; bugfix on 0.2.9.5-alpha.

  o Minor bugfixes (logging):
    - Downgrade a harmless log message about the
      pending_entry_connections list from "warn" to "info". Mitigates
      bug 19926.

  o Minor bugfixes (memory leak):
    - Fix a small memory leak when receiving AF_UNIX connections on a
      SocksPort. Fixes bug 20716; bugfix on 0.2.6.3-alpha.
    - When moving a signed descriptor object from a source to an
      existing destination, free the allocated memory inside that
      destination object. Fixes bug 20715; bugfix on 0.2.8.3-alpha.

  o Minor bugfixes (memory leak, use-after-free, linux seccomp2 sandbox):
    - Fix a memory leak and use-after-free error when removing entries
      from the sandbox's getaddrinfo() cache. Fixes bug 20710; bugfix on
      0.2.5.5-alpha. Patch from "cypherpunks".

  o Minor bugfixes (portability):
    - Use the correct spelling of MAC_OS_X_VERSION_10_12 on configure.ac
      Fixes bug 20935; bugfix on 0.2.9.6-rc.

  o Minor bugfixes (unit tests):
    - Stop expecting NetBSD unit tests to report success for ipfw. Part
      of a fix for bug 19960; bugfix on 0.2.9.5-alpha.
    - Fix tolerances in unit tests for monotonic time comparisons
      between nanoseconds and microseconds. Previously, we accepted a 10
      us difference only, which is not realistic on every platform's
      clock_gettime(). Fixes bug 19974; bugfix on 0.2.9.1-alpha.
    - Remove a double-free in the single onion service unit test. Stop
      ignoring a return value. Make future changes less error-prone.
      Fixes bug 20864; bugfix on 0.2.9.6-rc.


Changes in version 0.2.8.11 - 2016-12-08
  Tor 0.2.8.11 backports fixes for additional portability issues that
  could prevent Tor from building correctly on OSX Sierra, or with
  OpenSSL 1.1. Affected users should upgrade; others can safely stay
  with 0.2.8.10.

  o Minor bugfixes (portability):
    - Avoid compilation errors when building on OSX Sierra. Sierra began
      to support the getentropy() and clock_gettime() APIs, but created
      a few problems in doing so. Tor 0.2.9 has a more thorough set of
      workarounds; in 0.2.8, we are just using the /dev/urandom and mach
      monotonic time interfaces. Fixes bug 20865. Bugfix
      on 0.2.8.1-alpha.

  o Minor bugfixes (portability, backport from 0.2.9.5-alpha):
    - Fix compilation with OpenSSL 1.1 and less commonly-used CPU
      architectures. Closes ticket 20588.


Changes in version 0.2.8.10 - 2016-12-02
  Tor 0.2.8.10 backports a fix for a bug that would sometimes make clients
  unusable after they left standby mode. It also backports fixes for
  a few portability issues and a small but problematic memory leak.

  o Major bugfixes (client reliability, backport from 0.2.9.5-alpha):
    - When Tor leaves standby because of a new application request, open
      circuits as needed to serve that request. Previously, we would
      potentially wait a very long time. Fixes part of bug 19969; bugfix
      on 0.2.8.1-alpha.

  o Major bugfixes (client performance, backport from 0.2.9.5-alpha):
    - Clients now respond to new application stream requests immediately
      when they arrive, rather than waiting up to one second before
      starting to handle them. Fixes part of bug 19969; bugfix
      on 0.2.8.1-alpha.

  o Minor bugfixes (portability, backport from 0.2.9.6-rc):
    - Work around a bug in the OSX 10.12 SDK that would prevent us from
      successfully targeting earlier versions of OSX. Resolves
      ticket 20235.

  o Minor bugfixes (portability, backport from 0.2.9.5-alpha):
    - Fix implicit conversion warnings under OpenSSL 1.1. Fixes bug
      20551; bugfix on 0.2.1.1-alpha.

  o Minor bugfixes (relay, backport from 0.2.9.5-alpha):
    - Work around a memory leak in OpenSSL 1.1 when encoding public
      keys. Fixes bug 20553; bugfix on 0.0.2pre8.

  o Minor features (geoip):
    - Update geoip and geoip6 to the November 3 2016 Maxmind GeoLite2
      Country database.

Changes in version 0.2.9.6-rc - 2016-12-02
  Tor 0.2.9.6-rc fixes a few remaining bugs found in the previous alpha
  version. We hope that it will be ready to become stable soon, and we
  encourage everyone to test this release. If no showstopper bugs are
  found here, the next 0.2.9 release will be stable.

  o Major bugfixes (relay, resolver, logging):
    - For relays that don't know their own address, avoid attempting a
      local hostname resolve for each descriptor we download. This
      will cut down on the number of "Success: chose address 'x.x.x.x'"
      log lines, and also avoid confusing clock jumps if the resolver
      is slow. Fixes bugs 20423 and 20610; bugfix on 0.2.8.1-alpha.

  o Minor bugfixes (client, fascistfirewall):
    - Avoid spurious warnings when ReachableAddresses or FascistFirewall
      is set. Fixes bug 20306; bugfix on 0.2.8.2-alpha.

  o Minor bugfixes (hidden services):
    - Stop ignoring the anonymity status of saved keys for hidden
      services and single onion services when first starting tor.
      Instead, refuse to start tor if any hidden service key has been
      used in a different hidden service anonymity mode. Fixes bug
      20638; bugfix on 17178 in 0.2.9.3-alpha; reported by ahf.

  o Minor bugfixes (portability):
    - Work around a bug in the OSX 10.12 SDK that would prevent us from
      successfully targeting earlier versions of OSX. Resolves
      ticket 20235.
    - Run correctly when built on Windows build environments that
      require _vcsprintf(). Fixes bug 20560; bugfix on 0.2.2.11-alpha.

  o Minor bugfixes (single onion services, Tor2web):
    - Stop complaining about long-term one-hop circuits deliberately
      created by single onion services and Tor2web. These log messages
      are intended to diagnose issue 8387, which relates to circuits
      hanging around forever for no reason. Fixes bug 20613; bugfix on
      0.2.9.1-alpha. Reported by "pastly".

  o Minor bugfixes (unit tests):
    - Stop spurious failures in the local interface address discovery
      unit tests. Fixes bug 20634; bugfix on 0.2.8.1-alpha; patch by
      Neel Chauhan.

  o Documentation:
    - Correct the minimum bandwidth value in torrc.sample, and queue a
      corresponding change for torrc.minimal. Closes ticket 20085.


Changes in version 0.2.9.5-alpha - 2016-11-08
  Tor 0.2.9.5-alpha fixes numerous bugs discovered in the previous alpha
  version. We believe one or two probably remain, and we encourage
  everyone to test this release.

  o Major bugfixes (client performance):
    - Clients now respond to new application stream requests immediately
      when they arrive, rather than waiting up to one second before
      starting to handle them. Fixes part of bug 19969; bugfix
      on 0.2.8.1-alpha.

  o Major bugfixes (client reliability):
    - When Tor leaves standby because of a new application request, open
      circuits as needed to serve that request. Previously, we would
      potentially wait a very long time. Fixes part of bug 19969; bugfix
      on 0.2.8.1-alpha.

  o Major bugfixes (download scheduling):
    - When using an exponential backoff schedule, do not give up on
      downloading just because we have failed a bunch of times. Since
      each delay is longer than the last, retrying indefinitely won't
      hurt. Fixes bug 20536; bugfix on 0.2.9.1-alpha.
    - If a consensus expires while we are waiting for certificates to
      download, stop waiting for certificates.
    - If we stop waiting for certificates less than a minute after we
      started downloading them, do not consider the certificate download
      failure a separate failure. Fixes bug 20533; bugfix
      on 0.2.0.9-alpha.
    - Remove the maximum delay on exponential-backoff scheduling. Since
      we now allow an infinite number of failures (see ticket 20536), we
      must now allow the time to grow longer on each failure. Fixes part
      of bug 20534; bugfix on 0.2.9.1-alpha.
    - Make our initial download delays closer to those from 0.2.8. Fixes
      another part of bug 20534; bugfix on 0.2.9.1-alpha.
    - When determining when to download a directory object, handle times
      after 2038 if the operating system supports them. (Someday this
      will be important!) Fixes bug 20587; bugfix on 0.2.8.1-alpha.
    - When using exponential backoff in test networks, use a lower
      exponent, so the delays do not vary as much. This helps test
      networks bootstrap consistently. Fixes bug 20597; bugfix on 20499.

  o Minor features (geoip):
    - Update geoip and geoip6 to the November 3 2016 Maxmind GeoLite2
      Country database.

  o Minor bugfixes (client directory scheduling):
    - Treat "relay too busy to answer request" as a failed request and a
      reason to back off on our retry frequency. This is safe now that
      exponential backoffs retry indefinitely, and avoids a bug where we
      would reset our download schedule erroneously. Fixes bug 20593;
      bugfix on 0.2.9.1-alpha.

  o Minor bugfixes (client, logging):
    - Remove a BUG warning in circuit_pick_extend_handshake(). Instead,
      assume all nodes support EXTEND2. Use ntor whenever a key is
      available. Fixes bug 20472; bugfix on 0.2.9.3-alpha.
    - On DNSPort, stop logging a BUG warning on a failed hostname
      lookup. Fixes bug 19869; bugfix on 0.2.9.1-alpha.

  o Minor bugfixes (hidden services):
    - When configuring hidden services, check every hidden service
      directory's permissions. Previously, we only checked the last
      hidden service. Fixes bug 20529; bugfix the work to fix 13942
      in 0.2.6.2-alpha.

  o Minor bugfixes (portability):
    - Fix compilation with OpenSSL 1.1 and less commonly-used CPU
      architectures. Closes ticket 20588.
    - Use ECDHE ciphers instead of ECDH in tortls tests. LibreSSL has
      removed the ECDH ciphers which caused the tests to fail on
      platforms which use it. Fixes bug 20460; bugfix on 0.2.8.1-alpha.
    - Fix implicit conversion warnings under OpenSSL 1.1. Fixes bug
      20551; bugfix on 0.2.1.1-alpha.

  o Minor bugfixes (relay bootstrap):
    - Ensure relays don't make multiple connections during bootstrap.
      Fixes bug 20591; bugfix on 0.2.8.1-alpha.

  o Minor bugfixes (relay):
    - Work around a memory leak in OpenSSL 1.1 when encoding public
      keys. Fixes bug 20553; bugfix on 0.0.2pre8.
    - Avoid a small memory leak when informing worker threads about
      rotated onion keys. Fixes bug 20401; bugfix on 0.2.6.3-alpha.
    - Do not try to parallelize workers more than 16x without the user
      explicitly configuring us to do so, even if we do detect more than
      16 CPU cores. Fixes bug 19968; bugfix on 0.2.3.1-alpha.

  o Minor bugfixes (single onion services):
    - Start correctly when creating a single onion service in a
      directory that did not previously exist. Fixes bug 20484; bugfix
      on 0.2.9.3-alpha.

  o Minor bugfixes (testing):
    - Avoid a unit test failure on systems with over 16 detectable CPU
      cores. Fixes bug 19968; bugfix on 0.2.3.1-alpha.

  o Documentation:
    - Clarify that setting HiddenServiceNonAnonymousMode requires you to
      also set "SOCKSPort 0". Fixes bug 20487; bugfix on 0.2.9.3-alpha.
    - Module-level documentation for several more modules. Closes
      tickets 19287 and 19290.


Changes in version 0.2.8.9 - 2016-10-17
  Tor 0.2.8.9 backports a fix for a security hole in previous versions
  of Tor that would allow a remote attacker to crash a Tor client,
  hidden service, relay, or authority. All Tor users should upgrade to
  this version, or to 0.2.9.4-alpha. Patches will be released for older
  versions of Tor.

  o Major features (security fixes, also in 0.2.9.4-alpha):
    - Prevent a class of security bugs caused by treating the contents
      of a buffer chunk as if they were a NUL-terminated string. At
      least one such bug seems to be present in all currently used
      versions of Tor, and would allow an attacker to remotely crash
      most Tor instances, especially those compiled with extra compiler
      hardening. With this defense in place, such bugs can't crash Tor,
      though we should still fix them as they occur. Closes ticket
      20384 (TROVE-2016-10-001).

  o Minor features (geoip):
    - Update geoip and geoip6 to the October 4 2016 Maxmind GeoLite2
      Country database.


Changes in version 0.2.9.4-alpha - 2016-10-17
  Tor 0.2.9.4-alpha fixes a security hole in previous versions of Tor
  that would allow a remote attacker to crash a Tor client, hidden
  service, relay, or authority. All Tor users should upgrade to this
  version, or to 0.2.8.9. Patches will be released for older versions
  of Tor.

  Tor 0.2.9.4-alpha also adds numerous small features and fix-ups to
  previous versions of Tor, including the implementation of a feature to
  future- proof the Tor ecosystem against protocol changes, some bug
  fixes necessary for Tor Browser to use unix domain sockets correctly,
  and several portability improvements. We anticipate that this will be
  the last alpha in the Tor 0.2.9 series, and that the next release will
  be a release candidate.

  o Major features (security fixes):
    - Prevent a class of security bugs caused by treating the contents
      of a buffer chunk as if they were a NUL-terminated string. At
      least one such bug seems to be present in all currently used
      versions of Tor, and would allow an attacker to remotely crash
      most Tor instances, especially those compiled with extra compiler
      hardening. With this defense in place, such bugs can't crash Tor,
      though we should still fix them as they occur. Closes ticket
      20384 (TROVE-2016-10-001).

  o Major features (subprotocol versions):
    - Tor directory authorities now vote on a set of recommended
      subprotocol versions, and on a set of required subprotocol
      versions. Clients and relays that lack support for a _required_
      subprotocol version will not start; those that lack support for a
      _recommended_ subprotocol version will warn the user to upgrade.
      Closes ticket 19958; implements part of proposal 264.
    - Tor now uses "subprotocol versions" to indicate compatibility.
      Previously, versions of Tor looked at the declared Tor version of
      a relay to tell whether they could use a given feature. Now, they
      should be able to rely on its declared subprotocol versions. This
      change allows compatible implementations of the Tor protocol(s) to
      exist without pretending to be 100% bug-compatible with particular
      releases of Tor itself. Closes ticket 19958; implements part of
      proposal 264.

  o Minor feature (fallback directories):
    - Remove broken fallbacks from the hard-coded fallback directory
      list. Closes ticket 20190; patch by teor.

  o Minor features (client, directory):
    - Since authorities now omit all routers that lack the Running and
      Valid flags, we assume that any relay listed in the consensus must
      have those flags. Closes ticket 20001; implements part of
      proposal 272.

  o Minor features (compilation, portability):
    - Compile correctly on MacOS 10.12 (aka "Sierra"). Closes
      ticket 20241.

  o Minor features (development tools, etags):
    - Teach the "make tags" Makefile target how to correctly find
      "MOCK_IMPL" function definitions. Patch from nherring; closes
      ticket 16869.

  o Minor features (geoip):
    - Update geoip and geoip6 to the October 4 2016 Maxmind GeoLite2
      Country database.

  o Minor features (unix domain sockets):
    - When configuring a unix domain socket for a SocksPort,
      ControlPort, or Hidden service, you can now wrap the address in
      quotes, using C-style escapes inside the quotes. This allows unix
      domain socket paths to contain spaces.

  o Minor features (virtual addresses):
    - Increase the maximum number of bits for the IPv6 virtual network
      prefix from 16 to 104. In this way, the condition for address
      allocation is less restrictive. Closes ticket 20151; feature
      on 0.2.4.7-alpha.

  o Minor bugfixes (address discovery):
    - Stop reordering IP addresses returned by the OS. This makes it
      more likely that Tor will guess the same relay IP address every
      time. Fixes issue 20163; bugfix on 0.2.7.1-alpha, ticket 17027.
      Reported by René Mayrhofer, patch by "cypherpunks".

  o Minor bugfixes (client, unix domain sockets):
    - Disable IsolateClientAddr when using AF_UNIX backed SocksPorts as
      the client address is meaningless. Fixes bug 20261; bugfix
      on 0.2.6.3-alpha.

  o Minor bugfixes (compilation, OpenBSD):
    - Detect Libevent2 functions correctly on systems that provide
      libevent2, but where libevent1 is linked with -levent. Fixes bug
      19904; bugfix on 0.2.2.24-alpha. Patch from Rubiate.

  o Minor bugfixes (configuration):
    - When parsing quoted configuration values from the torrc file,
      handle windows line endings correctly. Fixes bug 19167; bugfix on
      0.2.0.16-alpha. Patch from "Pingl".

  o Minor bugfixes (getpass):
    - Defensively fix a non-triggerable heap corruption at do_getpass()
      to protect ourselves from mistakes in the future. Fixes bug
      19223; bugfix on 0.2.7.3-rc. Bug found by Guido Vranken, patch
      by nherring.

  o Minor bugfixes (hidden service):
    - Allow hidden services to run on IPv6 addresses even when the
      IPv6Exit option is not set. Fixes bug 18357; bugfix
      on 0.2.4.7-alpha.

  o Documentation:
    - Add module-level internal documentation for 36 C files that
      previously didn't have a high-level overview. Closes ticket #20385.

  o Required libraries:
    - When building with OpenSSL, Tor now requires version 1.0.1 or
      later. OpenSSL 1.0.0 and earlier are no longer supported by the
      OpenSSL team, and should not be used. Closes ticket 20303.


Changes in version 0.2.9.3-alpha - 2016-09-23
  Tor 0.2.9.3-alpha adds improved support for entities that want to make
  high-performance services available through the Tor .onion mechanism
  without themselves receiving anonymity as they host those services. It
  also tries harder to ensure that all steps on a circuit are using the
  strongest crypto possible, strengthens some TLS properties, and
  resolves several bugs -- including a pair of crash bugs from the 0.2.8
  series. Anybody running an earlier version of 0.2.9.x should upgrade.

  o Major bugfixes (crash, also in 0.2.8.8):
    - Fix a complicated crash bug that could affect Tor clients
      configured to use bridges when replacing a networkstatus consensus
      in which one of their bridges was mentioned. OpenBSD users saw
      more crashes here, but all platforms were potentially affected.
      Fixes bug 20103; bugfix on 0.2.8.2-alpha.

  o Major bugfixes (relay, OOM handler, also in 0.2.8.8):
    - Fix a timing-dependent assertion failure that could occur when we
      tried to flush from a circuit after having freed its cells because
      of an out-of-memory condition. Fixes bug 20203; bugfix on
      0.2.8.1-alpha. Thanks to "cypherpunks" for help diagnosing
      this one.

  o Major features (circuit building, security):
    - Authorities, relays and clients now require ntor keys in all
      descriptors, for all hops (except for rare hidden service protocol
      cases), for all circuits, and for all other roles. Part of
      ticket 19163.
    - Tor authorities, relays, and clients only use ntor, except for
      rare cases in the hidden service protocol. Part of ticket 19163.

  o Major features (single-hop "hidden" services):
    - Add experimental HiddenServiceSingleHopMode and
      HiddenServiceNonAnonymousMode options. When both are set to 1,
      every hidden service on a Tor instance becomes a non-anonymous
      Single Onion Service. Single Onions make one-hop (direct)
      connections to their introduction and renzedvous points. One-hop
      circuits make Single Onion servers easily locatable, but clients
      remain location-anonymous. This is compatible with the existing
      hidden service implementation, and works on the current tor
      network without any changes to older relays or clients. Implements
      proposal 260, completes ticket 17178. Patch by teor and asn.

  o Major features (resource management):
    - Tor can now notice it is about to run out of sockets, and
      preemptively close connections of lower priority. (This feature is
      off by default for now, since the current prioritizing method is
      yet not mature enough. You can enable it by setting
      "DisableOOSCheck 0", but watch out: it might close some sockets
      you would rather have it keep.) Closes ticket 18640.

  o Major bugfixes (circuit building):
    - Hidden service client-to-intro-point and service-to-rendezvous-
      point circuits use the TAP key supplied by the protocol, to avoid
      epistemic attacks. Fixes bug 19163; bugfix on 0.2.4.18-rc.

  o Major bugfixes (compilation, OpenBSD):
    - Fix a Libevent-detection bug in our autoconf script that would
      prevent Tor from linking successfully on OpenBSD. Patch from
      rubiate. Fixes bug 19902; bugfix on 0.2.9.1-alpha.

  o Major bugfixes (hidden services):
    - Clients now require hidden services to include the TAP keys for
      their intro points in the hidden service descriptor. This prevents
      an inadvertent upgrade to ntor, which a malicious hidden service
      could use to distinguish clients by consensus version. Fixes bug
      20012; bugfix on 0.2.4.8-alpha. Patch by teor.

  o Minor features (security, TLS):
    - Servers no longer support clients that without AES ciphersuites.
      (3DES is no longer considered an acceptable cipher.) We believe
      that no such Tor clients currently exist, since Tor has required
      OpenSSL 0.9.7 or later since 2009. Closes ticket 19998.

  o Minor feature (fallback directories):
    - Remove 8 fallbacks that are no longer suitable, leaving 81 of the
      100 fallbacks originally introduced in Tor 0.2.8.2-alpha in March
      2016. Closes ticket 20190; patch by teor.

  o Minor features (geoip, also in 0.2.8.8):
    - Update geoip and geoip6 to the September 6 2016 Maxmind GeoLite2
      Country database.

  o Minor feature (port flags):
    - Add new flags to the *Port options to finer control over which
      requests are allowed. The flags are NoDNSRequest, NoOnionTraffic,
      and the synthetic flag OnionTrafficOnly, which is equivalent to
      NoDNSRequest, NoIPv4Traffic, and NoIPv6Traffic. Closes enhancement
      18693; patch by "teor".

  o Minor features (directory authority):
    - After voting, if the authorities decide that a relay is not
      "Valid", they no longer include it in the consensus at all. Closes
      ticket 20002; implements part of proposal 272.

  o Minor features (testing):
    - Disable memory protections on OpenBSD when performing our unit
      tests for memwipe(). The test deliberately invokes undefined
      behavior, and the OpenBSD protections interfere with this. Patch
      from "rubiate". Closes ticket 20066.

  o Minor features (testing, ipv6):
    - Add the single-onion and single-onion-ipv6 chutney targets to
      "make test-network-all". This requires a recent chutney version
      with the single onion network flavours (git c72a652 or later).
      Closes ticket 20072; patch by teor.
    - Add the hs-ipv6 chutney target to make test-network-all's IPv6
      tests. Remove bridges+hs, as it's somewhat redundant. This
      requires a recent chutney version that supports IPv6 clients,
      relays, and authorities. Closes ticket 20069; patch by teor.

  o Minor features (Tor2web):
    - Make Tor2web clients respect ReachableAddresses. This feature was
      inadvertently enabled in 0.2.8.6, then removed by bugfix 19973 on
      0.2.8.7. Implements feature 20034. Patch by teor.

  o Minor features (unit tests):
    - We've done significant work to make the unit tests run faster.
    - Our link-handshake unit tests now check that when invalid
      handshakes fail, they fail with the error messages we expected.
    - Our unit testing code that captures log messages no longer
      prevents them from being written out if the user asked for them
      (by passing --debug or --info or or --notice --warn to the "test"
      binary). This change prevents us from missing unexpected log
      messages simply because we were looking for others. Related to
      ticket 19999.
    - The unit tests now log all warning messages with the "BUG" flag.
      Previously, they only logged errors by default. This change will
      help us make our testing code more correct, and make sure that we
      only hit this code when we mean to. In the meantime, however,
      there will be more warnings in the unit test logs than before.
      This is preparatory work for ticket 19999.
    - The unit tests now treat any failure of a "tor_assert_nonfatal()"
      assertion as a test failure.

  o Minor bug fixes (circuits):
    - Use the CircuitBuildTimeout option whenever
      LearnCircuitBuildTimeout is disabled. Previously, we would respect
      the option when a user disabled it, but not when it was disabled
      because some other option was set. Fixes bug 20073; bugfix on
      0.2.4.12-alpha. Patch by teor.

  o Minor bugfixes (allocation):
    - Change how we allocate memory for large chunks on buffers, to
      avoid a (currently impossible) integer overflow, and to waste less
      space when allocating unusually large chunks. Fixes bug 20081;
      bugfix on 0.2.0.16-alpha. Issue identified by Guido Vranken.
    - Always include orconfig.h before including any other C headers.
      Sometimes, it includes macros that affect the behavior of the
      standard headers. Fixes bug 19767; bugfix on 0.2.9.1-alpha (the
      first version to use AC_USE_SYSTEM_EXTENSIONS).
    - Fix a syntax error in the IF_BUG_ONCE__() macro in non-GCC-
      compatible compilers. Fixes bug 20141; bugfix on 0.2.9.1-alpha.
      Patch from Gisle Vanem.
    - Stop trying to build with Clang 4.0's -Wthread-safety warnings.
      They apparently require a set of annotations that we aren't
      currently using, and they create false positives in our pthreads
      wrappers. Fixes bug 20110; bugfix on 0.2.9.1-alpha.

  o Minor bugfixes (directory authority):
    - Die with a more useful error when the operator forgets to place
      the authority_signing_key file into the keys directory. This
      avoids an uninformative assert & traceback about having an invalid
      key. Fixes bug 20065; bugfix on 0.2.0.1-alpha.
    - When allowing private addresses, mark Exits that only exit to
      private locations as such. Fixes bug 20064; bugfix
      on 0.2.2.9-alpha.

  o Minor bugfixes (documentation):
    - Document the default PathsNeededToBuildCircuits value that's used
      by clients when the directory authorities don't set
      min_paths_for_circs_pct. Fixes bug 20117; bugfix on 02c320916e02
      in 0.2.4.10-alpha. Patch by teor, reported by Jesse V.
    - Fix manual for the User option: it takes a username, not a UID.
      Fixes bug 19122; bugfix on 0.0.2pre16 (the first version to have
      a manpage!).

  o Minor bugfixes (hidden services):
    - Stop logging intro point details to the client log on certain
      error conditions. Fixed as part of bug 20012; bugfix on
      0.2.4.8-alpha. Patch by teor.

  o Minor bugfixes (IPv6, testing):
    - Check for IPv6 correctly on Linux when running test networks.
      Fixes bug 19905; bugfix on 0.2.7.3-rc; patch by teor.

  o Minor bugfixes (Linux seccomp2 sandbox):
    - Add permission to run the sched_yield() and sigaltstack() system
      calls, in order to support versions of Tor compiled with asan or
      ubsan code that use these calls. Now "sandbox 1" and
      "--enable-expensive-hardening" should be compatible on more
      systems. Fixes bug 20063; bugfix on 0.2.5.1-alpha.

  o Minor bugfixes (logging):
    - When logging a message from the BUG() macro, be explicit about
      what we were asserting. Previously we were confusing what we were
      asserting with what the bug was. Fixes bug 20093; bugfix
      on 0.2.9.1-alpha.
    - When we are unable to remove the bw_accounting file, do not warn
      if the reason we couldn't remove it was that it didn't exist.
      Fixes bug 19964; bugfix on 0.2.5.4-alpha. Patch from 'pastly'.

  o Minor bugfixes (option parsing):
    - Count unix sockets when counting client listeners (SOCKS, Trans,
      NATD, and DNS). This has no user-visible behaviour changes: these
      options are set once, and never read. Required for correct
      behaviour in ticket 17178. Fixes bug 19677; bugfix on
      0.2.6.3-alpha. Patch by teor.

  o Minor bugfixes (options):
    - Check the consistency of UseEntryGuards and EntryNodes more
      reliably. Fixes bug 20074; bugfix on 0.2.4.12-alpha. Patch
      by teor.
    - Stop changing the configured value of UseEntryGuards on
      authorities and Tor2web clients. Fixes bug 20074; bugfix on
      commits 51fc6799 in 0.1.1.16-rc and acda1735 in 0.2.4.3-alpha.
      Patch by teor.

  o Minor bugfixes (Tor2web):
    - Prevent Tor2web clients running hidden services, these services
      are not anonymous due to the one-hop client paths. Fixes bug
      19678. Patch by teor.

  o Minor bugfixes (unit tests):
    - Fix a shared-random unit test that was failing on big endian
      architectures due to internal representation of a integer copied
      to a buffer. The test is changed to take a full 32 bytes of data
      and use the output of a python script that make the COMMIT and
      REVEAL calculation according to the spec. Fixes bug 19977; bugfix
      on 0.2.9.1-alpha.
    - The tor_tls_server_info_callback unit test no longer crashes when
      debug-level logging is turned on. Fixes bug 20041; bugfix
      on 0.2.8.1-alpha.


Changes in version 0.2.8.8 - 2016-09-23
  Tor 0.2.8.8 fixes two crash bugs present in previous versions of the
  0.2.8.x series. Relays running 0.2.8.x should upgrade, as should users
  who select public relays as their bridges.

  o Major bugfixes (crash):
    - Fix a complicated crash bug that could affect Tor clients
      configured to use bridges when replacing a networkstatus consensus
      in which one of their bridges was mentioned. OpenBSD users saw
      more crashes here, but all platforms were potentially affected.
      Fixes bug 20103; bugfix on 0.2.8.2-alpha.

  o Major bugfixes (relay, OOM handler):
    - Fix a timing-dependent assertion failure that could occur when we
      tried to flush from a circuit after having freed its cells because
      of an out-of-memory condition. Fixes bug 20203; bugfix on
      0.2.8.1-alpha. Thanks to "cypherpunks" for help diagnosing
      this one.

  o Minor feature (fallback directories):
    - Remove 8 fallbacks that are no longer suitable, leaving 81 of the
      100 fallbacks originally introduced in Tor 0.2.8.2-alpha in March
      2016. Closes ticket 20190; patch by teor.

  o Minor features (geoip):
    - Update geoip and geoip6 to the September 6 2016 Maxmind GeoLite2
      Country database.


Changes in version 0.2.9.2-alpha - 2016-08-24
  Tor 0.2.9.2-alpha continues development of the 0.2.9 series with
  several new features and bugfixes. It also includes an important
  authority update and an important bugfix from 0.2.8.7. Everyone who
  sets the ReachableAddresses option, and all bridges, are strongly
  encouraged to upgrade to 0.2.8.7, or to 0.2.9.2-alpha.

  o Directory authority changes (also in 0.2.8.7):
    - The "Tonga" bridge authority has been retired; the new bridge
      authority is "Bifroest". Closes tickets 19728 and 19690.

  o Major bugfixes (client, security, also in 0.2.8.7):
    - Only use the ReachableAddresses option to restrict the first hop
      in a path. In earlier versions of 0.2.8.x, it would apply to
      every hop in the path, with a possible degradation in anonymity
      for anyone using an uncommon ReachableAddress setting. Fixes bug
      19973; bugfix on 0.2.8.2-alpha.

  o Major features (user interface):
    - Tor now supports the ability to declare options deprecated, so
      that we can recommend that people stop using them. Previously,
      this was done in an ad-hoc way. Closes ticket 19820.

  o Major bugfixes (directory downloads):
    - Avoid resetting download status for consensuses hourly, since we
      already have another, smarter retry mechanism. Fixes bug 8625;
      bugfix on 0.2.0.9-alpha.

  o Minor features (config):
    - Warn users when descriptor and port addresses are inconsistent.
      Mitigates bug 13953; patch by teor.

  o Minor features (geoip):
    - Update geoip and geoip6 to the August 2 2016 Maxmind GeoLite2
      Country database.

  o Minor features (user interface):
    - There is a new --list-deprecated-options command-line option to
      list all of the deprecated options. Implemented as part of
      ticket 19820.

  o Minor bugfixes (code style):
    - Fix an integer signedness conversion issue in the case conversion
      tables. Fixes bug 19168; bugfix on 0.2.1.11-alpha.

  o Minor bugfixes (compilation):
    - Build correctly on versions of libevent2 without support for
      evutil_secure_rng_add_bytes(). Fixes bug 19904; bugfix
      on 0.2.5.4-alpha.
    - Fix a compilation warning on GCC versions before 4.6. Our
      ENABLE_GCC_WARNING macro used the word "warning" as an argument,
      when it is also required as an argument to the compiler pragma.
      Fixes bug 19901; bugfix on 0.2.9.1-alpha.

  o Minor bugfixes (compilation, also in 0.2.8.7):
    - Remove an inappropriate "inline" in tortls.c that was causing
      warnings on older versions of GCC. Fixes bug 19903; bugfix
      on 0.2.8.1-alpha.

  o Minor bugfixes (fallback directories, also in 0.2.8.7):
    - Avoid logging a NULL string pointer when loading fallback
      directory information. Fixes bug 19947; bugfix on 0.2.4.7-alpha
      and 0.2.8.1-alpha. Report and patch by "rubiate".

  o Minor bugfixes (logging):
    - Log a more accurate message when we fail to dump a microdescriptor.
      Fixes bug 17758; bugfix on 0.2.2.8-alpha. Patch from Daniel Pinto.

  o Minor bugfixes (memory leak):
    - Fix a series of slow memory leaks related to parsing torrc files
      and options. Fixes bug 19466; bugfix on 0.2.1.6-alpha.

  o Deprecated features:
    - A number of DNS-cache-related sub-options for client ports are now
      deprecated for security reasons, and may be removed in a future
      version of Tor. (We believe that client-side DNS caching is a bad
      idea for anonymity, and you should not turn it on.) The options
      are: CacheDNS, CacheIPv4DNS, CacheIPv6DNS, UseDNSCache,
      UseIPv4Cache, and UseIPv6Cache.
    - A number of options are deprecated for security reasons, and may
      be removed in a future version of Tor. The options are:
      AllowDotExit, AllowInvalidNodes, AllowSingleHopCircuits,
      AllowSingleHopExits, ClientDNSRejectInternalAddresses,
      CloseHSClientCircuitsImmediatelyOnTimeout,
      CloseHSServiceRendCircuitsImmediatelyOnTimeout,
      ExcludeSingleHopRelays, FastFirstHopPK, TLSECGroup,
      UseNTorHandshake, and WarnUnsafeSocks.
    - The *ListenAddress options are now deprecated as unnecessary: the
      corresponding *Port options should be used instead. These options
      may someday be removed. The affected options are:
      ControlListenAddress, DNSListenAddress, DirListenAddress,
      NATDListenAddress, ORListenAddress, SocksListenAddress,
      and TransListenAddress.

  o Documentation:
    - Correct the IPv6 syntax in our documentation for the
      VirtualAddrNetworkIPv6 torrc option. Closes ticket 19743.

  o Removed code:
    - We no longer include the (dead, deprecated) bufferevent code in
      Tor. Closes ticket 19450. Based on a patch from U+039b.


Changes in version 0.2.8.7 - 2016-08-24
  Tor 0.2.8.7 fixes an important bug related to the ReachableAddresses
  option in 0.2.8.6, and replaces a retiring bridge authority. Everyone
  who sets the ReachableAddresses option, and all bridges, are strongly
  encouraged to upgrade.

  o Directory authority changes:
    - The "Tonga" bridge authority has been retired; the new bridge
      authority is "Bifroest". Closes tickets 19728 and 19690.

  o Major bugfixes (client, security):
    - Only use the ReachableAddresses option to restrict the first hop
      in a path. In earlier versions of 0.2.8.x, it would apply to
      every hop in the path, with a possible degradation in anonymity
      for anyone using an uncommon ReachableAddress setting. Fixes bug
      19973; bugfix on 0.2.8.2-alpha.

  o Minor features (geoip):
    - Update geoip and geoip6 to the August 2 2016 Maxmind GeoLite2
      Country database.

  o Minor bugfixes (compilation):
    - Remove an inappropriate "inline" in tortls.c that was causing
      warnings on older versions of GCC. Fixes bug 19903; bugfix
      on 0.2.8.1-alpha.

  o Minor bugfixes (fallback directories):
    - Avoid logging a NULL string pointer when loading fallback
      directory information. Fixes bug 19947; bugfix on 0.2.4.7-alpha
      and 0.2.8.1-alpha. Report and patch by "rubiate".


Changes in version 0.2.9.1-alpha - 2016-08-08
  Tor 0.2.9.1-alpha is the first alpha release in the 0.2.9 development
  series. It improves our support for hardened builds and compiler
  warnings, deploys some critical infrastructure for improvements to
  hidden services, includes a new timing backend that we hope to use for
  better support for traffic padding, makes it easier for programmers to
  log unexpected events, and contains other small improvements to
  security, correctness, and performance.

  Below are the changes since 0.2.8.6.

  o New system requirements:
    - Tor now requires Libevent version 2.0.10-stable or later. Older
      versions of Libevent have less efficient backends for several
      platforms, and lack the DNS code that we use for our server-side
      DNS support. This implements ticket 19554.
    - Tor now requires zlib version 1.2 or later, for security,
      efficiency, and (eventually) gzip support. (Back when we started,
      zlib 1.1 and zlib 1.0 were still found in the wild. 1.2 was
      released in 2003. We recommend the latest version.)

  o Major features (build, hardening):
    - Tor now builds with -ftrapv by default on compilers that support
      it. This option detects signed integer overflow (which C forbids),
      and turns it into a hard-failure. We do not apply this option to
      code that needs to run in constant time to avoid side-channels;
      instead, we use -fwrapv in that code. Closes ticket 17983.
    - When --enable-expensive-hardening is selected, stop applying the
      clang/gcc sanitizers to code that needs to run in constant time.
      Although we are aware of no introduced side-channels, we are not
      able to prove that there are none. Related to ticket 17983.

  o Major features (compilation):
    - Our big list of extra GCC warnings is now enabled by default when
      building with GCC (or with anything like Clang that claims to be
      GCC-compatible). To make all warnings into fatal compilation
      errors, pass --enable-fatal-warnings to configure. Closes
      ticket 19044.
    - Use the Autoconf macro AC_USE_SYSTEM_EXTENSIONS to automatically
      turn on C and POSIX extensions. (Previously, we attempted to do
      this on an ad hoc basis.) Closes ticket 19139.

  o Major features (directory authorities, hidden services):
    - Directory authorities can now perform the shared randomness
      protocol specified by proposal 250. Using this protocol, directory
      authorities generate a global fresh random value every day. In the
      future, this value will be used by hidden services to select
      HSDirs. This release implements the directory authority feature;
      the hidden service side will be implemented in the future as part
      of proposal 224. Resolves ticket 16943; implements proposal 250.

  o Major features (downloading, random exponential backoff):
    - When we fail to download an object from a directory service, wait
      for an (exponentially increasing) randomized amount of time before
      retrying, rather than a fixed interval as we did before. This
      prevents a group of Tor instances from becoming too synchronized,
      or a single Tor instance from becoming too predictable, in its
      download schedule. Closes ticket 15942.

  o Major bugfixes (exit policies):
    - Avoid disclosing exit outbound bind addresses, configured port
      bind addresses, and local interface addresses in relay descriptors
      by default under ExitPolicyRejectPrivate. Instead, only reject
      these (otherwise unlisted) addresses if
      ExitPolicyRejectLocalInterfaces is set. Fixes bug 18456; bugfix on
      0.2.7.2-alpha. Patch by teor.

  o Major bugfixes (hidden service client):
    - Allow Tor clients with appropriate controllers to work with
      FetchHidServDescriptors set to 0. Previously, this option also
      disabled descriptor cache lookup, thus breaking hidden services
      entirely. Fixes bug 18704; bugfix on 0.2.0.20-rc. Patch by "twim".

  o Minor features (build, hardening):
    - Detect and work around a libclang_rt problem that would prevent
      clang from finding __mulodi4() on some 32-bit platforms, and thus
      keep -ftrapv from linking on those systems. Closes ticket 19079.
    - When building on a system without runtime support for the runtime
      hardening options, try to log a useful warning at configuration
      time, rather than an incomprehensible warning at link time. If
      expensive hardening was requested, this warning becomes an error.
      Closes ticket 18895.

  o Minor features (code safety):
    - In our integer-parsing functions, ensure that maxiumum value we
      give is no smaller than the minimum value. Closes ticket 19063;
      patch from U+039b.

  o Minor features (controller):
    - Implement new GETINFO queries for all downloads that use
      download_status_t to schedule retries. This allows controllers to
      examine the schedule for pending downloads. Closes ticket 19323.
    - Allow controllers to configure basic client authorization on
      hidden services when they create them with the ADD_ONION control
      command. Implements ticket 15588. Patch by "special".
    - Fire a STATUS_SERVER controller event whenever the hibernation
      status changes between "awake"/"soft"/"hard". Closes ticket 18685.

  o Minor features (directory authority):
    - Directory authorities now only give the Guard flag to a relay if
      they are also giving it the Stable flag. This change allows us to
      simplify path selection for clients. It should have minimal effect
      in practice, since >99% of Guards already have the Stable flag.
      Implements ticket 18624.
    - Directory authorities now write their v3-status-votes file out to
      disk earlier in the consensus process, so we have a record of the
      votes even if we abort the consensus process. Resolves
      ticket 19036.

  o Minor features (hidden service):
    - Stop being so strict about the payload length of "rendezvous1"
      cells. We used to be locked in to the "TAP" handshake length, and
      now we can handle better handshakes like "ntor". Resolves
      ticket 18998.

  o Minor features (infrastructure, time):
    - Tor now uses the operating system's monotonic timers (where
      available) for internal fine-grained timing. Previously we would
      look at the system clock, and then attempt to compensate for the
      clock running backwards. Closes ticket 18908.
    - Tor now includes an improved timer backend, so that we can
      efficiently support tens or hundreds of thousands of concurrent
      timers, as will be needed for some of our planned anti-traffic-
      analysis work. This code is based on William Ahern's "timeout.c"
      project, which implements a "tickless hierarchical timing wheel".
      Closes ticket 18365.

  o Minor features (logging):
    - Provide a more useful warning message when configured with an
      invalid Nickname. Closes ticket 18300; patch from "icanhasaccount".
    - When dumping unparseable router descriptors, optionally store them
      in separate files, named by digest, up to a configurable size
      limit. You can change the size limit by setting the
      MaxUnparseableDescSizeToLog option, and disable this feature by
      setting that option to 0. Closes ticket 18322.
    - Add a set of macros to check nonfatal assertions, for internal
      use. Migrating more of our checks to these should help us avoid
      needless crash bugs. Closes ticket 18613.

  o Minor features (performance):
    - Changer the "optimistic data" extension from "off by default" to
      "on by default". The default was ordinarily overridden by a
      consensus option, but when clients were bootstrapping for the
      first time, they would not have a consensus to get the option
      from. Changing this default When fetching a consensus for the
      first time, use optimistic data. This saves a round-trip during
      startup. Closes ticket 18815.

  o Minor features (relay, usability):
    - When the directory authorities refuse a bad relay's descriptor,
      encourage the relay operator to contact us. Many relay operators
      won't notice this line in their logs, but it's a win if even a few
      learn why we don't like what their relay was doing. Resolves
      ticket 18760.

  o Minor features (testing):
    - Let backtrace tests work correctly under AddressSanitizer. Fixes
      part of bug 18934; bugfix on 0.2.5.2-alpha.
    - Move the test-network.sh script to chutney, and modify tor's test-
      network.sh to call the (newer) chutney version when available.
      Resolves ticket 19116. Patch by teor.
    - Use the lcov convention for marking lines as unreachable, so that
      we don't count them when we're generating test coverage data.
      Update our coverage tools to understand this convention. Closes
      ticket 16792.

  o Minor bugfixes (bootstrap):
    - Remember the directory we fetched the consensus or previous
      certificates from, and use it to fetch future authority
      certificates. This change improves bootstrapping performance.
      Fixes bug 18963; bugfix on 0.2.8.1-alpha.

  o Minor bugfixes (build):
    - The test-stem and test-network makefile targets now depend only on
      the tor binary that they are testing. Previously, they depended on
      "make all". Fixes bug 18240; bugfix on 0.2.8.2-alpha. Based on a
      patch from "cypherpunks".

  o Minor bugfixes (circuits):
    - Make sure extend_info_from_router() is only called on servers.
      Fixes bug 19639; bugfix on 0.2.8.1-alpha.

  o Minor bugfixes (compilation):
    - When building with Clang, use a full set of GCC warnings.
      (Previously, we included only a subset, because of the way we
      detected them.) Fixes bug 19216; bugfix on 0.2.0.1-alpha.

  o Minor bugfixes (directory authority):
    - Authorities now sort the "package" lines in their votes, for ease
      of debugging. (They are already sorted in consensus documents.)
      Fixes bug 18840; bugfix on 0.2.6.3-alpha.
    - When parsing a detached signature, make sure we use the length of
      the digest algorithm instead of an hardcoded DIGEST256_LEN in
      order to avoid comparing bytes out-of-bounds with a smaller digest
      length such as SHA1. Fixes bug 19066; bugfix on 0.2.2.6-alpha.

  o Minor bugfixes (documentation):
    - Document the --passphrase-fd option in the tor manpage. Fixes bug
      19504; bugfix on 0.2.7.3-rc.
    - Fix the description of the --passphrase-fd option in the
      tor-gencert manpage. The option is used to pass the number of a
      file descriptor to read the passphrase from, not to read the file
      descriptor from. Fixes bug 19505; bugfix on 0.2.0.20-alpha.

  o Minor bugfixes (ephemeral hidden service):
    - When deleting an ephemeral hidden service, close its intro points
      even if they are not completely open. Fixes bug 18604; bugfix
      on 0.2.7.1-alpha.

  o Minor bugfixes (guard selection):
    - Use a single entry guard even if the NumEntryGuards consensus
      parameter is not provided. Fixes bug 17688; bugfix
      on 0.2.5.6-alpha.
    - Don't mark guards as unreachable if connection_connect() fails.
      That function fails for local reasons, so it shouldn't reveal
      anything about the status of the guard. Fixes bug 14334; bugfix
      on 0.2.3.10-alpha.

  o Minor bugfixes (hidden service client):
    - Increase the minimum number of internal circuits we preemptively
      build from 2 to 3, so a circuit is available when a client
      connects to another onion service. Fixes bug 13239; bugfix
      on 0.1.0.1-rc.

  o Minor bugfixes (logging):
    - When logging a directory ownership mismatch, log the owning
      username correctly. Fixes bug 19578; bugfix on 0.2.2.29-beta.

  o Minor bugfixes (memory leaks):
    - Fix a small, uncommon memory leak that could occur when reading a
      truncated ed25519 key file. Fixes bug 18956; bugfix
      on 0.2.6.1-alpha.

  o Minor bugfixes (testing):
    - Allow clients to retry HSDirs much faster in test networks. Fixes
      bug 19702; bugfix on 0.2.7.1-alpha. Patch by teor.
    - Disable ASAN's detection of segmentation faults while running
      test_bt.sh, so that we can make sure that our own backtrace
      generation code works. Fixes another aspect of bug 18934; bugfix
      on 0.2.5.2-alpha. Patch from "cypherpunks".
    - Fix the test-network-all target on out-of-tree builds by using the
      correct path to the test driver script. Fixes bug 19421; bugfix
      on 0.2.7.3-rc.

  o Minor bugfixes (time):
    - Improve overflow checks in tv_udiff and tv_mdiff. Fixes bug 19483;
      bugfix on all released tor versions.
    - When computing the difference between two times in milliseconds,
      we now round to the nearest millisecond correctly. Previously, we
      could sometimes round in the wrong direction. Fixes bug 19428;
      bugfix on 0.2.2.2-alpha.

  o Minor bugfixes (user interface):
    - Display a more accurate number of suppressed messages in the log
      rate-limiter. Previously, there was a potential integer overflow
      in the counter. Now, if the number of messages hits a maximum, the
      rate-limiter doesn't count any further. Fixes bug 19435; bugfix
      on 0.2.4.11-alpha.
    - Fix a typo in the passphrase prompt for the ed25519 identity key.
      Fixes bug 19503; bugfix on 0.2.7.2-alpha.

  o Code simplification and refactoring:
    - Remove redundant declarations of the MIN macro. Closes
      ticket 18889.
    - Rename tor_dup_addr() to tor_addr_to_str_dup() to avoid confusion.
      Closes ticket 18462; patch from "icanhasaccount".
    - Split the 600-line directory_handle_command_get function into
      separate functions for different URL types. Closes ticket 16698.

  o Documentation:
    - Fix spelling of "--enable-tor2web-mode" in the manpage. Closes
      ticket 19153. Patch from "U+039b".

  o Removed features:
    - Remove support for "GET /tor/bytes.txt" DirPort request, and
      "GETINFO dir-usage" controller request, which were only available
      via a compile-time option in Tor anyway. Feature was added in
      0.2.2.1-alpha. Resolves ticket 19035.
    - There is no longer a compile-time option to disable support for
      TransPort. (If you don't want TransPort; just don't use it.) Patch
      from "U+039b". Closes ticket 19449.

  o Testing:
    - Run more workqueue tests as part of "make check". These had
      previously been implemented, but you needed to know special
      command-line options to enable them.
    - We now have unit tests for our code to reject zlib "compression
      bombs". (Fortunately, the code works fine.)


Changes in version 0.2.8.6 - 2016-08-02

  Tor 0.2.8.6 is the first stable version of the Tor 0.2.8 series.

  The Tor 0.2.8 series improves client bootstrapping performance,
  completes the authority-side implementation of improved identity
  keys for relays, and includes numerous bugfixes and performance
  improvements throughout the program. This release continues to
  improve the coverage of Tor's test suite.  For a full list of
  changes since Tor 0.2.7, see the ReleaseNotes file.

  Changes since 0.2.8.5-rc:

  o Minor features (geoip):
    - Update geoip and geoip6 to the July 6 2016 Maxmind GeoLite2
      Country database.

  o Minor bugfixes (compilation):
    - Fix a compilation warning in the unit tests on systems where char
      is signed. Fixes bug 19682; bugfix on 0.2.8.1-alpha.

  o Minor bugfixes (fallback directories):
    - Remove 1 fallback that was on the hardcoded list, then opted-out,
      leaving 89 of the 100 fallbacks originally introduced in Tor
      0.2.8.2-alpha in March 2016. Closes ticket 19782; patch by teor.

  o Minor bugfixes (Linux seccomp2 sandbox):
    - Allow more syscalls when running with "Sandbox 1" enabled:
      sysinfo, getsockopt(SO_SNDBUF), and setsockopt(SO_SNDBUFFORCE). On
      some systems, these are required for Tor to start. Fixes bug
      18397; bugfix on 0.2.5.1-alpha. Patch from Daniel Pinto.
    - Allow IPPROTO_UDP datagram sockets when running with "Sandbox 1",
      so that get_interface_address6_via_udp_socket_hack() can work.
      Fixes bug 19660; bugfix on 0.2.5.1-alpha.


Changes in version 0.2.8.5-rc - 2016-07-07
  Tor 0.2.8.5-rc is the second release candidate in the Tor 0.2.8
  series. If we find no new bugs or regressions here, the first stable
  0.2.8 release will be identical to it. It has a few small bugfixes
  against previous versions.

  o Directory authority changes:
    - Urras is no longer a directory authority. Closes ticket 19271.

  o Major bugfixes (heartbeat):
    - Fix a regression that would crash Tor when the periodic
      "heartbeat" log messages were disabled. Fixes bug 19454; bugfix on
      0.2.8.1-alpha. Reported by "kubaku".

  o Minor features (build):
    - Tor now again builds with the recent OpenSSL 1.1 development
      branch (tested against 1.1.0-pre6-dev). Closes ticket 19499.
    - When building manual pages, set the timezone to "UTC", so that the
      output is reproducible. Fixes bug 19558; bugfix on 0.2.2.9-alpha.
      Patch from intrigeri.

  o Minor bugfixes (fallback directory selection):
    - Avoid errors during fallback selection if there are no eligible
      fallbacks. Fixes bug 19480; bugfix on 0.2.8.3-alpha. Patch
      by teor.

  o Minor bugfixes (IPv6, microdescriptors):
    - Don't check node addresses when we only have a routerstatus. This
      allows IPv6-only clients to bootstrap by fetching microdescriptors
      from fallback directory mirrors. (The microdescriptor consensus
      has no IPv6 addresses in it.) Fixes bug 19608; bugfix
      on 0.2.8.2-alpha.

  o Minor bugfixes (logging):
    - Reduce pointlessly verbose log messages when directory servers
      can't be found. Fixes bug 18849; bugfix on 0.2.8.3-alpha and
      0.2.8.1-alpha. Patch by teor.
    - When a fallback directory changes its fingerprint from the hard-
      coded fingerprint, log a less severe, more explanatory log
      message. Fixes bug 18812; bugfix on 0.2.8.1-alpha. Patch by teor.

  o Minor bugfixes (Linux seccomp2 sandboxing):
    - Allow statistics to be written to disk when "Sandbox 1" is
      enabled. Fixes bugs 19556 and 19957; bugfix on 0.2.5.1-alpha and
      0.2.6.1-alpha respectively.

  o Minor bugfixes (user interface):
    - Remove a warning message "Service [scrubbed] not found after
      descriptor upload". This message appears when one uses HSPOST
      control command to upload a service descriptor. Since there is
      only a descriptor and no service, showing this message is
      pointless and confusing. Fixes bug 19464; bugfix on 0.2.7.2-alpha.

  o Fallback directory list:
    - Add a comment to the generated fallback directory list that
      explains how to comment out unsuitable fallbacks in a way that's
      compatible with the stem fallback parser.
    - Update fallback whitelist and blacklist based on relay operator
      emails. Blacklist unsuitable (non-working, over-volatile)
      fallbacks. Resolves ticket 19071. Patch by teor.
    - Remove 10 unsuitable fallbacks, leaving 90 of the 100 fallbacks
      originally introduced in Tor 0.2.8.2-alpha in March 2016. Closes
      ticket 19071; patch by teor.


Changes in version 0.2.8.4-rc - 2016-06-15
  Tor 0.2.8.4-rc is the first release candidate in the Tor 0.2.8 series.
  If we find no new bugs or regressions here, the first stable 0.2.8
  release will be identical to it. It has a few small bugfixes against
  previous versions.

  o Major bugfixes (user interface):
    - Correctly give a warning in the cases where a relay is specified
      by nickname, and one such relay is found, but it is not officially
      Named. Fixes bug 19203; bugfix on 0.2.3.1-alpha.

  o Minor features (build):
    - Tor now builds once again with the recent OpenSSL 1.1 development
      branch (tested against 1.1.0-pre5 and 1.1.0-pre6-dev).

  o Minor features (geoip):
    - Update geoip and geoip6 to the June 7 2016 Maxmind GeoLite2
      Country database.

  o Minor bugfixes (compilation):
    - Cause the unit tests to compile correctly on mingw64 versions that
      lack sscanf. Fixes bug 19213; bugfix on 0.2.7.1-alpha.

  o Minor bugfixes (downloading):
    - Predict more correctly whether we'll be downloading over HTTP when
      we determine the maximum length of a URL. This should avoid a
      "BUG" warning about the Squid HTTP proxy and its URL limits. Fixes
      bug 19191.


Changes in version 0.2.8.3-alpha - 2016-05-26
  Tor 0.2.8.3-alpha resolves several bugs, most of them introduced over
  the course of the 0.2.8 development cycle. It improves the behavior of
  directory clients, fixes several crash bugs, fixes a gap in compiler
  hardening, and allows the full integration test suite to run on
  more platforms.

  o Major bugfixes (security, client, DNS proxy):
    - Stop a crash that could occur when a client running with DNSPort
      received a query with multiple address types, and the first
      address type was not supported. Found and fixed by Scott Dial.
      Fixes bug 18710; bugfix on 0.2.5.4-alpha.

  o Major bugfixes (security, compilation):
    - Correctly detect compiler flags on systems where _FORTIFY_SOURCE
      is predefined. Previously, our use of -D_FORTIFY_SOURCE would
      cause a compiler warning, thereby making other checks fail, and
      needlessly disabling compiler-hardening support. Fixes one case of
      bug 18841; bugfix on 0.2.3.17-beta. Patch from "trudokal".

  o Major bugfixes (security, directory authorities):
    - Fix a crash and out-of-bounds write during authority voting, when
      the list of relays includes duplicate ed25519 identity keys. Fixes
      bug 19032; bugfix on 0.2.8.2-alpha.

  o Major bugfixes (client, bootstrapping):
    - Check if bootstrap consensus downloads are still needed when the
      linked connection attaches. This prevents tor making unnecessary
      begindir-style connections, which are the only directory
      connections tor clients make since the fix for 18483 was merged.
    - Fix some edge cases where consensus download connections may not
      have been closed, even though they were not needed. Related to fix
      for 18809.
    - Make relays retry consensus downloads the correct number of times,
      rather than the more aggressive client retry count. Fixes part of
      ticket 18809.
    - Stop downloading consensuses when we have a consensus, even if we
      don't have all the certificates for it yet. Fixes bug 18809;
      bugfix on 0.2.8.1-alpha. Patches by arma and teor.

  o Major bugfixes (directory mirrors):
    - Decide whether to advertise begindir support in the the same way
      we decide whether to advertise our DirPort. Allowing these
      decisions to become out-of-sync led to surprising behavior like
      advertising begindir support when hibernation made us not
      advertise a DirPort. Resolves bug 18616; bugfix on 0.2.8.1-alpha.
      Patch by teor.

  o Major bugfixes (IPv6 bridges, client):
    - Actually use IPv6 addresses when selecting directory addresses for
      IPv6 bridges. Fixes bug 18921; bugfix on 0.2.8.1-alpha. Patch
      by "teor".

  o Major bugfixes (key management):
    - If OpenSSL fails to generate an RSA key, do not retain a dangling
      pointer to the previous (uninitialized) key value. The impact here
      should be limited to a difficult-to-trigger crash, if OpenSSL is
      running an engine that makes key generation failures possible, or
      if OpenSSL runs out of memory. Fixes bug 19152; bugfix on
      0.2.1.10-alpha. Found by Yuan Jochen Kang, Suman Jana, and
      Baishakhi Ray.

  o Major bugfixes (testing):
    - Fix a bug that would block 'make test-network-all' on systems where
      IPv6 packets were lost. Fixes bug 19008; bugfix on 0.2.7.3-rc.
    - Avoid "WSANOTINITIALISED" warnings in the unit tests. Fixes bug 18668;
      bugfix on 0.2.8.1-alpha.

  o Minor features (clients):
    - Make clients, onion services, and bridge relays always use an
      encrypted begindir connection for directory requests. Resolves
      ticket 18483. Patch by "teor".

  o Minor features (fallback directory mirrors):
    - Give each fallback the same weight for client selection; restrict
      fallbacks to one per operator; report fallback directory detail
      changes when rebuilding list; add new fallback directory mirrors
      to the whitelist; and many other minor simplifications and fixes.
      Closes tasks 17905, 18749, bug 18689, and fixes part of bug 18812 on
      0.2.8.1-alpha; patch by "teor".
    - Replace the 21 fallbacks generated in January 2016 and included in
      Tor 0.2.8.1-alpha, with a list of 100 fallbacks generated in March
      2016. Closes task 17158; patch by "teor".

  o Minor features (geoip):
    - Update geoip and geoip6 to the May 4 2016 Maxmind GeoLite2
      Country database.

  o Minor bugfixes (assert, portability):
    - Fix an assertion failure in memarea.c on systems where "long" is
      shorter than the size of a pointer. Fixes bug 18716; bugfix
      on 0.2.1.1-alpha.

  o Minor bugfixes (bootstrap):
    - Consistently use the consensus download schedule for authority
      certificates. Fixes bug 18816; bugfix on 0.2.4.13-alpha.

  o Minor bugfixes (build):
    - Remove a pair of redundant AM_CONDITIONAL declarations from
      configure.ac. Fixes one final case of bug 17744; bugfix
      on 0.2.8.2-alpha.
    - Resolve warnings when building on systems that are concerned with
      signed char. Fixes bug 18728; bugfix on 0.2.7.2-alpha
      and 0.2.6.1-alpha.
    - When libscrypt.h is found, but no libscrypt library can be linked,
      treat libscrypt as absent. Fixes bug 19161; bugfix
      on 0.2.6.1-alpha.

  o Minor bugfixes (client):
    - Turn all TestingClientBootstrap* into non-testing torrc options.
      This changes simply renames them by removing "Testing" in front of
      them and they do not require TestingTorNetwork to be enabled
      anymore. Fixes bug 18481; bugfix on 0.2.8.1-alpha.
    - Make directory node selection more reliable, mainly for IPv6-only
      clients and clients with few reachable addresses. Fixes bug 18929;
      bugfix on 0.2.8.1-alpha. Patch by "teor".

  o Minor bugfixes (controller, microdescriptors):
    - Make GETINFO dir/status-vote/current/consensus conform to the
      control specification by returning "551 Could not open cached
      consensus..." when not caching consensuses. Fixes bug 18920;
      bugfix on 0.2.2.6-alpha.

  o Minor bugfixes (crypto, portability):
    - The SHA3 and SHAKE routines now produce the correct output on Big
      Endian systems. No code calls either algorithm yet, so this is
      primarily a build fix. Fixes bug 18943; bugfix on 0.2.8.1-alpha.
    - Tor now builds again with the recent OpenSSL 1.1 development
      branch (tested against 1.1.0-pre4 and 1.1.0-pre5-dev). Closes
      ticket 18286.

  o Minor bugfixes (directories):
    - When fetching extrainfo documents, compare their SHA256 digests
      and Ed25519 signing key certificates with the routerinfo that led
      us to fetch them, rather than with the most recent routerinfo.
      Otherwise we generate many spurious warnings about mismatches.
      Fixes bug 17150; bugfix on 0.2.7.2-alpha.

  o Minor bugfixes (logging):
    - When we can't generate a signing key because OfflineMasterKey is
      set, do not imply that we should have been able to load it. Fixes
      bug 18133; bugfix on 0.2.7.2-alpha.
    - Stop periodic_event_dispatch() from blasting twelve lines per
      second at loglevel debug. Fixes bug 18729; fix on 0.2.8.1-alpha.
    - When rejecting a misformed INTRODUCE2 cell, only log at
      PROTOCOL_WARN severity. Fixes bug 18761; bugfix on 0.2.8.2-alpha.

  o Minor bugfixes (pluggable transports):
    - Avoid reporting a spurious error when we decide that we don't need
      to terminate a pluggable transport because it has already exited.
      Fixes bug 18686; bugfix on 0.2.5.5-alpha.

  o Minor bugfixes (pointer arithmetic):
    - Fix a bug in memarea_alloc() that could have resulted in remote
      heap write access, if Tor had ever passed an unchecked size to
      memarea_alloc(). Fortunately, all the sizes we pass to
      memarea_alloc() are pre-checked to be less than 128 kilobytes.
      Fixes bug 19150; bugfix on 0.2.1.1-alpha. Bug found by
      Guido Vranken.

  o Minor bugfixes (relays):
    - Consider more config options when relays decide whether to
      regenerate their descriptor. Fixes more of bug 12538; bugfix
      on 0.2.8.1-alpha.
    - Resolve some edge cases where we might launch an ORPort
      reachability check even when DisableNetwork is set. Noticed while
      fixing bug 18616; bugfix on 0.2.3.9-alpha.

  o Minor bugfixes (statistics):
    - We now include consensus downloads via IPv6 in our directory-
      request statistics. Fixes bug 18460; bugfix on 0.2.3.14-alpha.

  o Minor bugfixes (testing):
    - Allow directories in small networks to bootstrap by skipping
      DirPort checks when the consensus has no exits. Fixes bug 19003;
      bugfix on 0.2.8.1-alpha. Patch by teor.
    - Fix a small memory leak that would occur when the
      TestingEnableCellStatsEvent option was turned on. Fixes bug 18673;
      bugfix on 0.2.5.2-alpha.

  o Minor bugfixes (time handling):
    - When correcting a corrupt 'struct tm' value, fill in the tm_wday
      field. Otherwise, our unit tests crash on Windows. Fixes bug
      18977; bugfix on 0.2.2.25-alpha.

  o Documentation:
    - Document the contents of the 'datadir/keys' subdirectory in the
      manual page. Closes ticket 17621.
    - Stop recommending use of nicknames to identify relays in our
      MapAddress documentation. Closes ticket 18312.


Changes in version 0.2.8.2-alpha - 2016-03-28
  Tor 0.2.8.2-alpha is the second alpha in its series. It fixes numerous
  bugs in earlier versions of Tor, including some that prevented
  authorities using Tor 0.2.7.x from running correctly. IPv6 and
  directory support should also be much improved.

  o New system requirements:
    - Tor no longer supports versions of OpenSSL with a broken
      implementation of counter mode. (This bug was present in OpenSSL
      1.0.0, and was fixed in OpenSSL 1.0.0a.) Tor still detects, but no
      longer runs with, these versions.
    - Tor no longer attempts to support platforms where the "time_t"
      type is unsigned. (To the best of our knowledge, only OpenVMS does
      this, and Tor has never actually built on OpenVMS.) Closes
      ticket 18184.
    - Tor now uses Autoconf version 2.63 or later, and Automake 1.11 or
      later (released in 2008 and 2009 respectively). If you are
      building Tor from the git repository instead of from the source
      distribution, and your tools are older than this, you will need to
      upgrade. Closes ticket 17732.

  o Major bugfixes (security, pointers):
    - Avoid a difficult-to-trigger heap corruption attack when extending
      a smartlist to contain over 16GB of pointers. Fixes bug 18162;
      bugfix on 0.1.1.11-alpha, which fixed a related bug incompletely.
      Reported by Guido Vranken.

  o Major bugfixes (bridges, pluggable transports):
    - Modify the check for OR connections to private addresses. Allow
      bridges on private addresses, including pluggable transports that
      ignore the (potentially private) address in the bridge line. Fixes
      bug 18517; bugfix on 0.2.8.1-alpha. Reported by gk, patch by teor.

  o Major bugfixes (compilation):
    - Repair hardened builds under the clang compiler. Previously, our
      use of _FORTIFY_SOURCE would conflict with clang's address
      sanitizer. Fixes bug 14821; bugfix on 0.2.5.4-alpha.

  o Major bugfixes (crash on shutdown):
    - Correctly handle detaching circuits from muxes when shutting down.
      Fixes bug 18116; bugfix on 0.2.8.1-alpha.
    - Fix an assert-on-exit bug related to counting memory usage in
      rephist.c. Fixes bug 18651; bugfix on 0.2.8.1-alpha.

  o Major bugfixes (crash on startup):
    - Fix a segfault during startup: If a Unix domain socket was
      configured as listener (such as a ControlSocket or a SocksPort
      "unix:" socket), and tor was started as root but not configured to
      switch to another user, tor would segfault while trying to string
      compare a NULL value. Fixes bug 18261; bugfix on 0.2.8.1-alpha.
      Patch by weasel.

  o Major bugfixes (dns proxy mode, crash):
    - Avoid crashing when running as a DNS proxy. Fixes bug 16248;
      bugfix on 0.2.0.1-alpha. Patch from "cypherpunks".

  o Major bugfixes (relays, bridge clients):
    - Ensure relays always allow IPv4 OR and Dir connections. Ensure
      bridge clients use the address configured in the bridge line.
      Fixes bug 18348; bugfix on 0.2.8.1-alpha. Reported by sysrqb,
      patch by teor.

  o Major bugfixes (voting):
    - Actually enable support for authorities to match routers by their
      Ed25519 identities. Previously, the code had been written, but
      some debugging code that had accidentally been left in the
      codebase made it stay turned off. Fixes bug 17702; bugfix
      on 0.2.7.2-alpha.
    - When collating votes by Ed25519 identities, authorities now
      include a "NoEdConsensus" flag if the ed25519 value (or lack
      thereof) for a server does not reflect the majority consensus.
      Related to bug 17668; bugfix on 0.2.7.2-alpha.
    - When generating a vote with keypinning disabled, never include two
      entries for the same ed25519 identity. This bug was causing
      authorities to generate votes that they could not parse when a
      router violated key pinning by changing its RSA identity but
      keeping its Ed25519 identity. Fixes bug 17668; fixes part of bug
      18318. Bugfix on 0.2.7.2-alpha.

  o Minor features (security, win32):
    - Set SO_EXCLUSIVEADDRUSE on Win32 to avoid a local port-stealing
      attack. Fixes bug 18123; bugfix on all tor versions. Patch
      by teor.

  o Minor features (bug-resistance):
    - Make Tor survive errors involving connections without a
      corresponding event object. Previously we'd fail with an
      assertion; now we produce a log message. Related to bug 16248.

  o Minor features (build):
    - Detect systems with FreeBSD-derived kernels (such as GNU/kFreeBSD)
      as having possible IPFW support. Closes ticket 18448. Patch from
      Steven Chamberlain.

  o Minor features (code hardening):
    - Use tor_snprintf() and tor_vsnprintf() even in external and low-
      level code, to harden against accidental failures to NUL-
      terminate. Part of ticket 17852. Patch from jsturgix. Found
      with Flawfinder.

  o Minor features (crypto):
    - Validate the hard-coded Diffie-Hellman parameters and ensure that
      p is a safe prime, and g is a suitable generator. Closes
      ticket 18221.

  o Minor features (geoip):
    - Update geoip and geoip6 to the March 3 2016 Maxmind GeoLite2
      Country database.

  o Minor features (hidden service directory):
    - Streamline relay-side hsdir handling: when relays consider whether
      to accept an uploaded hidden service descriptor, they no longer
      check whether they are one of the relays in the network that is
      "supposed" to handle that descriptor. Implements ticket 18332.

  o Minor features (IPv6):
    - Add ClientPreferIPv6DirPort, which is set to 0 by default. If set
      to 1, tor prefers IPv6 directory addresses.
    - Add ClientUseIPv4, which is set to 1 by default. If set to 0, tor
      avoids using IPv4 for client OR and directory connections.
    - Try harder to obey the IP version restrictions "ClientUseIPv4 0",
      "ClientUseIPv6 0", "ClientPreferIPv6ORPort", and
      "ClientPreferIPv6DirPort". Closes ticket 17840; patch by teor.

  o Minor features (linux seccomp2 sandbox):
    - Reject attempts to change our Address with "Sandbox 1" enabled.
      Changing Address with Sandbox turned on would never actually work,
      but previously it would fail in strange and confusing ways. Found
      while fixing 18548.

  o Minor features (robustness):
    - Exit immediately with an error message if the code attempts to use
      Libevent without having initialized it. This should resolve some
      frequently-made mistakes in our unit tests. Closes ticket 18241.

  o Minor features (unix domain sockets):
    - Add a new per-socket option, RelaxDirModeCheck, to allow creating
      Unix domain sockets without checking the permissions on the parent
      directory. (Tor checks permissions by default because some
      operating systems only check permissions on the parent directory.
      However, some operating systems do look at permissions on the
      socket, and tor's default check is unneeded.) Closes ticket 18458.
      Patch by weasel.

  o Minor bugfixes (exit policies, security):
    - Refresh an exit relay's exit policy when interface addresses
      change. Previously, tor only refreshed the exit policy when the
      configured external address changed. Fixes bug 18208; bugfix on
      0.2.7.3-rc. Patch by teor.

  o Minor bugfixes (security, hidden services):
    - Prevent hidden services connecting to client-supplied rendezvous
      addresses that are reserved as internal or multicast. Fixes bug
      8976; bugfix on 0.2.3.21-rc. Patch by dgoulet and teor.

  o Minor bugfixes (build):
    - Do not link the unit tests against both the testing and non-
      testing versions of the static libraries. Fixes bug 18490; bugfix
      on 0.2.7.1-alpha.
    - Avoid spurious failures from configure files related to calling
      exit(0) in TOR_SEARCH_LIBRARY. Fixes bug 18626; bugfix on
      0.2.0.1-alpha. Patch from "cypherpunks".
    - Silence spurious clang-scan warnings in the ed25519_donna code by
      explicitly initializing some objects. Fixes bug 18384; bugfix on
      0.2.7.2-alpha. Patch by teor.

  o Minor bugfixes (client, bootstrap):
    - Count receipt of new microdescriptors as progress towards
      bootstrapping. Previously, with EntryNodes set, Tor might not
      successfully repopulate the guard set on bootstrapping. Fixes bug
      16825; bugfix on 0.2.3.1-alpha.

  o Minor bugfixes (code correctness):
    - Update to the latest version of Trunnel, which tries harder to
      avoid generating code that can invoke memcpy(p,NULL,0). Bug found
      by clang address sanitizer. Fixes bug 18373; bugfix
      on 0.2.7.2-alpha.

  o Minor bugfixes (configuration):
    - Fix a tiny memory leak when parsing a port configuration ending in
      ":auto". Fixes bug 18374; bugfix on 0.2.3.3-alpha.

  o Minor bugfixes (containers):
    - If we somehow attempt to construct a heap with more than
      1073741822 elements, avoid an integer overflow when maintaining
      the heap property. Fixes bug 18296; bugfix on 0.1.2.1-alpha.

  o Minor bugfixes (correctness):
    - Fix a bad memory handling bug that would occur if we had queued a
      cell on a channel's incoming queue. Fortunately, we can't actually
      queue a cell like that as our code is constructed today, but it's
      best to avoid this kind of error, even if there isn't any code
      that triggers it today. Fixes bug 18570; bugfix on 0.2.4.4-alpha.

  o Minor bugfixes (directory):
    - When generating a URL for a directory server on an IPv6 address,
      wrap the IPv6 address in square brackets. Fixes bug 18051; bugfix
      on 0.2.3.9-alpha. Patch from Malek.

  o Minor bugfixes (fallback directory mirrors):
    - When requesting extrainfo descriptors from a trusted directory
      server, check whether it is an authority or a fallback directory
      which supports extrainfo descriptors. Fixes bug 18489; bugfix on
      0.2.4.7-alpha. Reported by atagar, patch by teor.

  o Minor bugfixes (hidden service, client):
    - Handle the case where the user makes several fast consecutive
      requests to the same .onion address. Previously, the first six
      requests would each trigger a descriptor fetch, each picking a
      directory (there are 6 overall) and the seventh one would fail
      because no directories were left, thereby triggering a close on
      all current directory connections asking for the hidden service.
      The solution here is to not close the connections if we have
      pending directory fetches. Fixes bug 15937; bugfix
      on 0.2.7.1-alpha.

  o Minor bugfixes (hidden service, control port):
    - Add the onion address to the HS_DESC event for the UPLOADED action
      both on success or failure. It was previously hardcoded with
      UNKNOWN. Fixes bug 16023; bugfix on 0.2.7.2-alpha.

  o Minor bugfixes (hidden service, directory):
    - Bridges now refuse "rendezvous2" (hidden service descriptor)
      publish attempts. Suggested by ticket 18332.

  o Minor bugfixes (linux seccomp2 sandbox):
    - Allow the setrlimit syscall, and the prlimit and prlimit64
      syscalls, which some libc implementations use under the hood.
      Fixes bug 15221; bugfix on 0.2.5.1-alpha.
    - Avoid a 10-second delay when starting as a client with "Sandbox 1"
      enabled and no DNS resolvers configured. This should help TAILS
      start up faster. Fixes bug 18548; bugfix on 0.2.5.1-alpha.
    - Fix the sandbox's interoperability with unix domain sockets under
      setuid. Fixes bug 18253; bugfix on 0.2.8.1-alpha.

  o Minor bugfixes (logging):
    - When logging information about an unparsable networkstatus vote or
      consensus, do not say "vote" when we mean consensus. Fixes bug
      18368; bugfix on 0.2.0.8-alpha.
    - Scrub service name in "unrecognized service ID" log messages.
      Fixes bug 18600; bugfix on 0.2.4.11-alpha.
    - Downgrade logs and backtraces about IP versions to info-level.
      Only log backtraces once each time tor runs. Assists in diagnosing
      bug 18351; bugfix on 0.2.8.1-alpha. Reported by sysrqb and
      Christian, patch by teor.

  o Minor bugfixes (memory safety):
    - Avoid freeing an uninitialized pointer when opening a socket fails
      in get_interface_addresses_ioctl(). Fixes bug 18454; bugfix on
      0.2.3.11-alpha. Reported by toralf and "cypherpunks", patch
      by teor.
    - Correctly duplicate addresses in get_interface_address6_list().
      Fixes bug 18454; bugfix on 0.2.8.1-alpha. Reported by toralf,
      patch by "cypherpunks".
    - Fix a memory leak in tor-gencert. Fixes part of bug 18672; bugfix
      on 0.2.0.1-alpha.
    - Fix a memory leak in "tor --list-fingerprint". Fixes part of bug
      18672; bugfix on 0.2.5.1-alpha.

  o Minor bugfixes (private directory):
    - Prevent a race condition when creating private directories. Fixes
      part of bug 17852; bugfix on 0.0.2pre13. Part of ticket 17852.
      Patch from jsturgix. Found with Flawfinder.

  o Minor bugfixes (test networks, IPv6):
    - Allow internal IPv6 addresses in descriptors in test networks.
      Fixes bug 17153; bugfix on 0.2.3.16-alpha. Patch by teor, reported
      by karsten.

  o Minor bugfixes (testing):
    - We no longer disable assertions in the unit tests when coverage is
      enabled. Instead, we require you to say --disable-asserts-in-tests
      to the configure script if you need assertions disabled in the
      unit tests (for example, if you want to perform branch coverage).
      Fixes bug 18242; bugfix on 0.2.7.1-alpha.

  o Minor bugfixes (time parsing):
    - Avoid overflow in tor_timegm when parsing dates in and after 2038
      on platforms with 32-bit time_t. Fixes bug 18479; bugfix on
      0.0.2pre14. Patch by teor.

  o Minor bugfixes (tor-gencert):
    - Correctly handle the case where an authority operator enters a
      passphrase but sends an EOF before sending a newline. Fixes bug
      17443; bugfix on 0.2.0.20-rc. Found by junglefowl.

  o Code simplification and refactoring:
    - Quote all the string interpolations in configure.ac -- even those
      which we are pretty sure can't contain spaces. Closes ticket
      17744. Patch from zerosion.
    - Remove specialized code for non-inplace AES_CTR. 99% of our AES is
      inplace, so there's no need to have a separate implementation for
      the non-inplace code. Closes ticket 18258. Patch from Malek.
    - Simplify return types for some crypto functions that can't
      actually fail. Patch from Hassan Alsibyani. Closes ticket 18259.

  o Documentation:
    - Change build messages to refer to "Fedora" instead of "Fedora
      Core", and "dnf" instead of "yum". Closes tickets 18459 and 18426.
      Patches from "icanhasaccount" and "cypherpunks".

  o Removed features:
    - We no longer maintain an internal freelist in memarea.c.
      Allocators should be good enough to make this code unnecessary,
      and it's doubtful that it ever had any performance benefit.

  o Testing:
    - Fix several warnings from clang's address sanitizer produced in
      the unit tests.
    - Treat backtrace test failures as expected on FreeBSD until we
      solve bug 17808. Closes ticket 18204.


Changes in version 0.2.8.1-alpha - 2016-02-04
  Tor 0.2.8.1-alpha is the first alpha release in its series. It
  includes numerous small features and bugfixes against previous Tor
  versions, and numerous small infrastructure improvements. The most
  notable features are a set of improvements to the directory subsystem.

  o Major features (security, Linux):
    - When Tor starts as root on Linux and is told to switch user ID, it
      can now retain the capability to bind to low ports. By default,
      Tor will do this only when it's switching user ID and some low
      ports have been configured. You can change this behavior with the
      new option KeepBindCapabilities. Closes ticket 8195.

  o Major features (directory system):
    - When bootstrapping multiple consensus downloads at a time, use the
      first one that starts downloading, and close the rest. This
      reduces failures when authorities or fallback directories are slow
      or down. Together with the code for feature 15775, this feature
      should reduces failures due to fallback churn. Implements ticket
      4483. Patch by "teor". Implements IPv4 portions of proposal 210 by
      "mikeperry" and "teor".
    - Include a trial list of 21 default fallback directories, generated
      in January 2016, based on an opt-in survey of suitable relays.
      Doing this should make clients bootstrap more quickly and reliably,
      and reduce the load on the directory authorities. Closes ticket
      15775. Patch by "teor".
      Candidates identified using an OnionOO script by "weasel", "teor",
      "gsathya", and "karsten".
    - Previously only relays that explicitly opened a directory port
      (DirPort) accepted directory requests from clients. Now all
      relays, with and without a DirPort, accept and serve tunneled
      directory requests that they receive through their ORPort. You can
      disable this behavior using the new DirCache option. Closes
      ticket 12538.

  o Major key updates:
    - Update the V3 identity key for the dannenberg directory authority:
      it was changed on 18 November 2015. Closes task 17906. Patch
      by "teor".

  o Minor features (security, clock):
    - Warn when the system clock appears to move back in time (when the
      state file was last written in the future). Tor doesn't know that
      consensuses have expired if the clock is in the past. Patch by
      "teor". Implements ticket 17188.

  o Minor features (security, exit policies):
    - ExitPolicyRejectPrivate now rejects more private addresses by
      default. Specifically, it now rejects the relay's outbound bind
      addresses (if configured), and the relay's configured port
      addresses (such as ORPort and DirPort). Fixes bug 17027; bugfix on
      0.2.0.11-alpha. Patch by "teor".

  o Minor features (security, memory erasure):
    - Set the unused entries in a smartlist to NULL. This helped catch
      a (harmless) bug, and shouldn't affect performance too much.
      Implements ticket 17026.
    - Use SecureMemoryWipe() function to securely clean memory on
      Windows. Previously we'd use OpenSSL's OPENSSL_cleanse() function.
      Implements feature 17986.
    - Use explicit_bzero or memset_s when present. Previously, we'd use
      OpenSSL's OPENSSL_cleanse() function. Closes ticket 7419; patches
      from  and .
    - Make memwipe() do nothing when passed a NULL pointer or buffer of
      zero size. Check size argument to memwipe() for underflow. Fixes
      bug 18089; bugfix on 0.2.3.25 and 0.2.4.6-alpha. Reported by "gk",
      patch by "teor".

  o Minor features (security, RNG):
    - Adjust Tor's use of OpenSSL's RNG APIs so that they absolutely,
      positively are not allowed to fail. Previously we depended on
      internal details of OpenSSL's behavior. Closes ticket 17686.
    - Never use the system entropy output directly for anything besides
      seeding the PRNG. When we want to generate important keys, instead
      of using system entropy directly, we now hash it with the PRNG
      stream. This may help resist certain attacks based on broken OS
      entropy implementations. Closes part of ticket 17694.
    - Use modern system calls (like getentropy() or getrandom()) to
      generate strong entropy on platforms that have them. Closes
      ticket 13696.

  o Minor features (accounting):
    - Added two modes to the AccountingRule option: One for limiting
      only the number of bytes sent ("AccountingRule out"), and one for
      limiting only the number of bytes received ("AccountingRule in").
      Closes ticket 15989; patch from "unixninja92".

  o Minor features (build):
    - Since our build process now uses "make distcheck", we no longer
      force "make dist" to depend on "make check". Closes ticket 17893;
      patch from "cypherpunks."
    - Tor now builds successfully with the recent OpenSSL 1.1
      development branch, and with the latest LibreSSL. Closes tickets
      17549, 17921, and 17984.

  o Minor features (controller):
    - Adds the FallbackDir entries to 'GETINFO config/defaults'. Closes
      tickets 16774 and 17817. Patch by George Tankersley.
    - New 'GETINFO hs/service/desc/id/' command to retrieve a hidden
      service descriptor from a service's local hidden service
      descriptor cache. Closes ticket 14846.
    - Add 'GETINFO exit-policy/reject-private/[default,relay]', so
      controllers can examine the the reject rules added by
      ExitPolicyRejectPrivate. This makes it easier for stem to display
      exit policies.

  o Minor features (crypto):
    - Add SHA512 support to crypto.c. Closes ticket 17663; patch from
      George Tankersley.
    - Add SHA3 and SHAKE support to crypto.c. Closes ticket 17783.
    - When allocating a digest state object, allocate no more space than
      we actually need. Previously, we would allocate as much space as
      the state for the largest algorithm would need. This change saves
      up to 672 bytes per circuit. Closes ticket 17796.
    - Improve performance when hashing non-multiple of 8 sized buffers,
      based on Andrew Moon's public domain SipHash-2-4 implementation.
      Fixes bug 17544; bugfix on 0.2.5.3-alpha.

  o Minor features (directory downloads):
    - Wait for busy authorities and fallback directories to become non-
      busy when bootstrapping. (A similar change was made in 6c443e987d
      for directory caches chosen from the consensus.) Closes ticket
      17864; patch by "teor".
    - Add UseDefaultFallbackDirs, which enables any hard-coded fallback
      directory mirrors. The default is 1; set it to 0 to disable
      fallbacks. Implements ticket 17576. Patch by "teor".

  o Minor features (geoip):
    - Update geoip and geoip6 to the January 5 2016 Maxmind GeoLite2
      Country database.

  o Minor features (IPv6):
    - Add an argument 'ipv6=address:orport' to the DirAuthority and
      FallbackDir torrc options, to specify an IPv6 address for an
      authority or fallback directory. Add hard-coded ipv6 addresses for
      directory authorities that have them. Closes ticket 17327; patch
      from Nick Mathewson and "teor".
    - Add address policy assume_action support for IPv6 addresses.
    - Limit IPv6 mask bits to 128.
    - Warn when comparing against an AF_UNSPEC address in a policy, it's
      almost always a bug. Closes ticket 17863; patch by "teor".
    - Allow users to configure directory authorities and fallback
      directory servers with IPv6 addresses and ORPorts. Resolves
      ticket 6027.
    - routerset_parse now accepts IPv6 literal addresses. Fixes bug
      17060; bugfix on 0.2.1.3-alpha. Patch by "teor".
    - Make tor_ersatz_socketpair work on IPv6-only systems. Fixes bug
      17638; bugfix on 0.0.2pre8. Patch by "teor".

  o Minor features (logging):
    - When logging to syslog, allow a tag to be added to the syslog
      identity (the string prepended to every log message). The tag can
      be configured with SyslogIdentityTag and defaults to none. Setting
      it to "foo" will cause logs to be tagged as "Tor-foo". Closes
      ticket 17194.

  o Minor features (portability):
    - Use timingsafe_memcmp() where available. Closes ticket 17944;
      patch from .

  o Minor features (relay, address discovery):
    - Add a family argument to get_interface_addresses_raw() and
      subfunctions to make network interface address interogation more
      efficient. Now Tor can specifically ask for IPv4, IPv6 or both
      types of interfaces from the operating system. Resolves
      ticket 17950.
    - When get_interface_address6_list(.,AF_UNSPEC,.) is called and
      fails to enumerate interface addresses using the platform-specific
      API, have it rely on the UDP socket fallback technique to try and
      find out what IP addresses (both IPv4 and IPv6) our machine has.
      Resolves ticket 17951.

  o Minor features (replay cache):
    - The replay cache now uses SHA256 instead of SHA1. Implements
      feature 8961. Patch by "teor", issue reported by "rransom".

  o Minor features (unix file permissions):
    - Defer creation of Unix sockets until after setuid. This avoids
      needing CAP_CHOWN and CAP_FOWNER when using systemd's
      CapabilityBoundingSet, or chown and fowner when using SELinux.
      Implements part of ticket 17562. Patch from Jamie Nguyen.
    - If any directory created by Tor is marked as group readable, the
      filesystem group is allowed to be either the default GID or the
      root user. Allowing root to read the DataDirectory prevents the
      need for CAP_READ_SEARCH when using systemd's
      CapabilityBoundingSet, or dac_read_search when using SELinux.
      Implements part of ticket 17562. Patch from Jamie Nguyen.
    - Introduce a new DataDirectoryGroupReadable option. If it is set to
      1, the DataDirectory will be made readable by the default GID.
      Implements part of ticket 17562. Patch from Jamie Nguyen.

  o Minor bugfixes (accounting):
    - The max bandwidth when using 'AccountRule sum' is now correctly
      logged. Fixes bug 18024; bugfix on 0.2.6.1-alpha. Patch
      from "unixninja92".

  o Minor bugfixes (code correctness):
    - When closing an entry connection, generate a warning if we should
      have sent an end cell for it but we haven't. Fixes bug 17876;
      bugfix on 0.2.3.2-alpha.
    - Assert that allocated memory held by the reputation code is freed
      according to its internal counters. Fixes bug 17753; bugfix
      on 0.1.1.1-alpha.
    - Assert when the TLS contexts fail to initialize. Fixes bug 17683;
      bugfix on 0.0.6.

  o Minor bugfixes (compilation):
    - Mark all object files that include micro-revision.i as depending
      on it, so as to make parallel builds more reliable. Fixes bug
      17826; bugfix on 0.2.5.1-alpha.
    - Don't try to use the pthread_condattr_setclock() function unless
      it actually exists. Fixes compilation on NetBSD-6.x. Fixes bug
      17819; bugfix on 0.2.6.3-alpha.
    - Fix backtrace compilation on FreeBSD. Fixes bug 17827; bugfix
      on 0.2.5.2-alpha.
    - Fix compilation of sandbox.c with musl-libc. Fixes bug 17347;
      bugfix on 0.2.5.1-alpha. Patch from 'jamestk'.
    - Fix search for libevent libraries on OpenBSD (and other systems
      that install libevent 1 and libevent 2 in parallel). Fixes bug
      16651; bugfix on 0.1.0.7-rc. Patch from "rubiate".
    - Isolate environment variables meant for tests from the rest of the
      build system. Fixes bug 17818; bugfix on 0.2.7.3-rc.
    - Replace usage of 'INLINE' with 'inline'. Fixes bug 17804; bugfix
      on 0.0.2pre8.
    - Remove config.log only from make distclean, not from make clean.
      Fixes bug 17924; bugfix on 0.2.4.1-alpha.

  o Minor bugfixes (crypto):
    - Check the return value of HMAC() and assert on failure. Fixes bug
      17658; bugfix on 0.2.3.6-alpha. Patch by "teor".

  o Minor bugfixes (fallback directories):
    - Mark fallbacks as "too busy" when they return a 503 response,
      rather than just marking authorities. Fixes bug 17572; bugfix on
      0.2.4.7-alpha. Patch by "teor".

  o Minor bugfixes (IPv6):
    - Update the limits in max_dl_per_request for IPv6 address length.
      Fixes bug 17573; bugfix on 0.2.1.5-alpha.

  o Minor bugfixes (linux seccomp2 sandbox):
    - Fix a crash when using offline master ed25519 keys with the Linux
      seccomp2 sandbox enabled. Fixes bug 17675; bugfix on 0.2.7.3-rc.

  o Minor bugfixes (logging):
    - In log messages that include a function name, use __FUNCTION__
      instead of __PRETTY_FUNCTION__. In GCC, these are synonymous, but
      with clang __PRETTY_FUNCTION__ has extra information we don't
      need. Fixes bug 16563; bugfix on 0.0.2pre8. Fix by Tom van
      der Woerdt.
    - Remove needless quotes from a log message about unparseable
      addresses. Fixes bug 17843; bugfix on 0.2.3.3-alpha.

  o Minor bugfixes (portability):
    - Remove an #endif from configure.ac so that we correctly detect the
      presence of in6_addr.s6_addr32. Fixes bug 17923; bugfix
      on 0.2.0.13-alpha.

  o Minor bugfixes (relays):
    - Check that both the ORPort and DirPort (if present) are reachable
      before publishing a relay descriptor. Otherwise, relays publish a
      descriptor with DirPort 0 when the DirPort reachability test takes
      longer than the ORPort reachability test. Fixes bug 18050; bugfix
      on 0.1.0.1-rc. Reported by "starlight", patch by "teor".

  o Minor bugfixes (relays, hidden services):
    - Refuse connection requests to private OR addresses unless
      ExtendAllowPrivateAddresses is set. Previously, tor would connect,
      then refuse to send any cells to a private address. Fixes bugs
      17674 and 8976; bugfix on 0.2.3.21-rc. Patch by "teor".

  o Minor bugfixes (safe logging):
    - When logging a malformed hostname received through socks4, scrub
      it if SafeLogging says we should. Fixes bug 17419; bugfix
      on 0.1.1.16-rc.

  o Minor bugfixes (statistics code):
    - Consistently check for overflow in round_*_to_next_multiple_of
      functions, and add unit tests with additional and maximal values.
      Fixes part of bug 13192; bugfix on 0.2.2.1-alpha.
    - Handle edge cases in the laplace functions: avoid division by
      zero, avoid taking the log of zero, and silence clang type
      conversion warnings using round and trunc. Add unit tests for edge
      cases with maximal values. Fixes part of bug 13192; bugfix
      on 0.2.6.2-alpha.

  o Minor bugfixes (testing):
    - The test for log_heartbeat was incorrectly failing in timezones
      with non-integer offsets. Instead of comparing the end of the time
      string against a constant, compare it to the output of
      format_local_iso_time when given the correct input. Fixes bug
      18039; bugfix on 0.2.5.4-alpha.
    - Make unit tests pass on IPv6-only systems, and systems without
      localhost addresses (like some FreeBSD jails). Fixes bug 17632;
      bugfix on 0.2.7.3-rc. Patch by "teor".
    - Fix a memory leak in the ntor test. Fixes bug 17778; bugfix
      on 0.2.4.8-alpha.
    - Check the full results of SHA256 and SHA512 digests in the unit
      tests. Bugfix on 0.2.2.4-alpha. Patch by "teor".

  o Code simplification and refactoring:
    - Move logging of redundant policy entries in
      policies_parse_exit_policy_internal into its own function. Closes
      ticket 17608; patch from "juce".
    - Extract the more complicated parts of circuit_mark_for_close()
      into a new function that we run periodically before circuits are
      freed. This change removes more than half of the functions
      currently in the "blob". Closes ticket 17218.
    - Clean up a little duplicated code in
      crypto_expand_key_material_TAP(). Closes ticket 17587; patch
      from "pfrankw".
    - Decouple the list of streams waiting to be attached to circuits
      from the overall connection list. This change makes it possible to
      attach streams quickly while simplifying Tor's callgraph and
      avoiding O(N) scans of the entire connection list. Closes
      ticket 17590.
    - When a direct directory request fails immediately on launch,
      instead of relaunching that request from inside the code that
      launches it, instead mark the connection for teardown. This change
      simplifies Tor's callback and prevents the directory-request
      launching code from invoking itself recursively. Closes
      ticket 17589
    - Remove code for configuring OpenSSL dynamic locks; OpenSSL doesn't
      use them. Closes ticket 17926.

  o Documentation:
    - Add a description of the correct use of the '--keygen' command-
      line option. Closes ticket 17583; based on text by 's7r'.
    - Document the minimum HeartbeatPeriod value. Closes ticket 15638.
    - Explain actual minima for BandwidthRate. Closes ticket 16382.
    - Fix a minor formatting typo in the manpage. Closes ticket 17791.
    - Mention torspec URL in the manpage and point the reader to it
      whenever we mention a document that belongs in torspce. Fixes
      issue 17392.

  o Removed features:
    - Remove client-side support for connecting to Tor relays running
      versions of Tor before 0.2.3.6-alpha. These relays didn't support
      the v3 TLS handshake protocol, and are no longer allowed on the
      Tor network. Implements the client side of ticket 11150. Based on
      patches by Tom van der Woerdt.

  o Testing:
    - Add unit tests to check for common RNG failure modes, such as
      returning all zeroes, identical values, or incrementing values
      (OpenSSL's rand_predictable feature). Patch by "teor".
    - Log more information when the backtrace tests fail. Closes ticket
      17892. Patch from "cypherpunks."
    - Always test both ed25519 backends, so that we can be sure that our
      batch-open replacement code works. Part of ticket 16794.
    - Cover dns_resolve_impl() in dns.c with unit tests. Implements a
      portion of ticket 16831.
    - More unit tests for compat_libevent.c, procmon.c, tortls.c,
      util_format.c, directory.c, and options_validate.c. Closes tickets
      17075, 17082, 17084, 17003, and 17076 respectively. Patches from
      Ola Bini.
    - Unit tests for directory_handle_command_get. Closes ticket 17004.
      Patch from Reinaldo de Souza Jr.


Changes in version 0.2.7.6 - 2015-12-10
  Tor version 0.2.7.6 fixes a major bug in entry guard selection, as
  well as a minor bug in hidden service reliability.

  o Major bugfixes (guard selection):
    - Actually look at the Guard flag when selecting a new directory
      guard. When we implemented the directory guard design, we
      accidentally started treating all relays as if they have the Guard
      flag during guard selection, leading to weaker anonymity and worse
      performance. Fixes bug 17772; bugfix on 0.2.4.8-alpha. Discovered
      by Mohsen Imani.

  o Minor features (geoip):
    - Update geoip and geoip6 to the December 1 2015 Maxmind GeoLite2
      Country database.

  o Minor bugfixes (compilation):
    - When checking for net/pfvar.h, include netinet/in.h if possible.
      This fixes transparent proxy detection on OpenBSD. Fixes bug
      17551; bugfix on 0.1.2.1-alpha. Patch from "rubiate".
    - Fix a compilation warning with Clang 3.6: Do not check the
      presence of an address which can never be NULL. Fixes bug 17781.

  o Minor bugfixes (correctness):
    - When displaying an IPv6 exit policy, include the mask bits
      correctly even when the number is greater than 31. Fixes bug
      16056; bugfix on 0.2.4.7-alpha. Patch from "gturner".
    - The wrong list was used when looking up expired intro points in a
      rend service object, causing what we think could be reachability
      issues for hidden services, and triggering a BUG log. Fixes bug
      16702; bugfix on 0.2.7.2-alpha.
    - Fix undefined behavior in the tor_cert_checksig function. Fixes
      bug 17722; bugfix on 0.2.7.2-alpha.


Changes in version 0.2.7.5 - 2015-11-20
  The Tor 0.2.7 release series is dedicated to the memory of Tor user
  and privacy advocate Caspar Bowden (1961-2015). Caspar worked
  tirelessly to advocate human rights regardless of national borders,
  and oppose the encroachments of mass surveillance. He opposed national
  exceptionalism, he brought clarity to legal and policy debates, he
  understood and predicted the impact of mass surveillance on the world,
  and he laid the groundwork for resisting it. While serving on the Tor
  Project's board of directors, he brought us his uncompromising focus
  on technical excellence in the service of humankind. Caspar was an
  inimitable force for good and a wonderful friend. He was kind,
  humorous, generous, gallant, and believed we should protect one
  another without exception. We honor him here for his ideals, his
  efforts, and his accomplishments. Please honor his memory with works
  that would make him proud.

  Tor 0.2.7.5 is the first stable release in the Tor 0.2.7 series.

  The 0.2.7 series adds a more secure identity key type for relays,
  improves cryptography performance, resolves several longstanding
  hidden-service performance issues, improves controller support for
  hidden services, and includes small bugfixes and performance
  improvements throughout the program. This release series also includes
  more tests than before, and significant simplifications to which parts
  of Tor invoke which others.

  (This release contains no code changes since 0.2.7.4-rc.)


Changes in version 0.2.7.4-rc - 2015-10-21
  Tor 0.2.7.4-rc is the second release candidate in the 0.2.7 series. It
  fixes some important memory leaks, and a scary-looking (but mostly
  harmless in practice) invalid-read bug. It also has a few small
  bugfixes, notably fixes for compilation and portability on different
  platforms. If no further significant bounds are found, the next
  release will the the official stable release.

  o Major bugfixes (security, correctness):
    - Fix an error that could cause us to read 4 bytes before the
      beginning of an openssl string. This bug could be used to cause
      Tor to crash on systems with unusual malloc implementations, or
      systems with unusual hardening installed. Fixes bug 17404; bugfix
      on 0.2.3.6-alpha.

  o Major bugfixes (correctness):
    - Fix a use-after-free bug in validate_intro_point_failure(). Fixes
      bug 17401; bugfix on 0.2.7.3-rc.

  o Major bugfixes (memory leaks):
    - Fix a memory leak in ed25519 batch signature checking. Fixes bug
      17398; bugfix on 0.2.6.1-alpha.
    - Fix a memory leak in rend_cache_failure_entry_free(). Fixes bug
      17402; bugfix on 0.2.7.3-rc.
    - Fix a memory leak when reading an expired signing key from disk.
      Fixes bug 17403; bugfix on 0.2.7.2-rc.

  o Minor features (geoIP):
    - Update geoip and geoip6 to the October 9 2015 Maxmind GeoLite2
      Country database.

  o Minor bugfixes (compilation):
    - Repair compilation with the most recent (unreleased, alpha)
      vesions of OpenSSL 1.1. Fixes part of ticket 17237.
    - Fix an integer overflow warning in test_crypto_slow.c. Fixes bug
      17251; bugfix on 0.2.7.2-alpha.
    - Fix compilation of sandbox.c with musl-libc. Fixes bug 17347;
      bugfix on 0.2.5.1-alpha. Patch from 'jamestk'.

  o Minor bugfixes (portability):
    - Use libexecinfo on FreeBSD to enable backtrace support. Fixes
      part of bug 17151; bugfix on 0.2.5.2-alpha. Patch from
      Marcin Cieślak.

  o Minor bugfixes (sandbox):
    - Add the "hidserv-stats" filename to our sandbox filter for the
      HiddenServiceStatistics option to work properly. Fixes bug 17354;
      bugfix on 0.2.6.2-alpha. Patch from David Goulet.

  o Minor bugfixes (testing):
    - Add unit tests for get_interface_address* failure cases. Fixes bug
      17173; bugfix on 0.2.7.3-rc. Patch by fk/teor.
    - Fix breakage when running 'make check' with BSD make. Fixes bug
      17154; bugfix on 0.2.7.3-rc. Patch by Marcin Cieślak.
    - Make the get_ifaddrs_* unit tests more tolerant of different
      network configurations. (Don't assume every test box has an IPv4
      address, and don't assume every test box has a non-localhost
      address.) Fixes bug 17255; bugfix on 0.2.7.3-rc. Patch by "teor".
    - Skip backtrace tests when backtrace support is not compiled in.
      Fixes part of bug 17151; bugfix on 0.2.7.1-alpha. Patch from
      Marcin Cieślak.

  o Documentation:
    - Fix capitalization of SOCKS in sample torrc. Closes ticket 15609.
    - Note that HiddenServicePorts can take a unix domain socket. Closes
      ticket 17364.


Changes in version 0.2.7.3-rc - 2015-09-25
  Tor 0.2.7.3-rc is the first release candidate in the 0.2.7 series. It
  contains numerous usability fixes for Ed25519 keys, safeguards against
  several misconfiguration problems, significant simplifications to
  Tor's callgraph, and numerous bugfixes and small features.

  This is the most tested release of Tor to date. The unit tests cover
  39.40% of the code, and the integration tests (accessible with "make
  test-full-online", requiring stem and chutney and a network
  connection) raise the coverage to 64.49%.

  o Major features (security, hidden services):
    - Hidden services, if using the EntryNodes option, are required to
      use more than one EntryNode, in order to avoid a guard discovery
      attack. (This would only affect people who had configured hidden
      services and manually specified the EntryNodes option with a
      single entry-node. The impact was that it would be easy to
      remotely identify the guard node used by such a hidden service.
      See ticket for more information.) Fixes ticket 14917.

  o Major features (Ed25519 keys, keypinning):
    - The key-pinning option on directory authorities is now advisory-
      only by default. In a future version, or when the AuthDirPinKeys
      option is set, pins are enforced again. Disabling key-pinning
      seemed like a good idea so that we can survive the fallout of any
      usability problems associated with Ed25519 keys. Closes
      ticket 17135.

  o Major features (Ed25519 performance):
    - Improve the speed of Ed25519 operations and Curve25519 keypair
      generation when built targeting 32 bit x86 platforms with SSE2
      available. Implements ticket 16535.
    - Improve the runtime speed of Ed25519 signature verification by
      using Ed25519-donna's batch verification support. Implements
      ticket 16533.

  o Major features (performance testing):
    - The test-network.sh script now supports performance testing.
      Requires corresponding chutney performance testing changes. Patch
      by "teor". Closes ticket 14175.

  o Major features (relay, Ed25519):
    - Significant usability improvements for Ed25519 key management. Log
      messages are better, and the code can recover from far more
      failure conditions. Thanks to "s7r" for reporting and diagnosing
      so many of these!
    - Add a new OfflineMasterKey option to tell Tor never to try loading
      or generating a secret Ed25519 identity key. You can use this in
      combination with tor --keygen to manage offline and/or encrypted
      Ed25519 keys. Implements ticket 16944.
    - Add a --newpass option to allow changing or removing the
      passphrase of an encrypted key with tor --keygen. Implements part
      of ticket 16769.
    - On receiving a HUP signal, check to see whether the Ed25519
      signing key has changed, and reload it if so. Closes ticket 16790.

  o Major bugfixes (relay, Ed25519):
    - Avoid crashing on 'tor --keygen'. Fixes bug 16679; bugfix on
      0.2.7.2-alpha. Reported by "s7r".
    - Improve handling of expired signing keys with offline master keys.
      Fixes bug 16685; bugfix on 0.2.7.2-alpha. Reported by "s7r".

  o Minor features (client-side privacy):
    - New KeepAliveIsolateSOCKSAuth option to indefinitely extend circuit
      lifespan when IsolateSOCKSAuth and streams with SOCKS
      authentication are attached to the circuit. This allows
      applications like TorBrowser to manage circuit lifetime on their
      own. Implements feature 15482.
    - When logging malformed hostnames from SOCKS5 requests, respect
      SafeLogging configuration. Fixes bug 16891; bugfix on 0.1.1.16-rc.

  o Minor features (compilation):
    - Give a warning as early as possible when trying to build with an
      unsupported OpenSSL version. Closes ticket 16901.
    - Fail during configure if we're trying to build against an OpenSSL
      built without ECC support. Fixes bug 17109, bugfix on 0.2.7.1-alpha
      which started requiring ECC.

  o Minor features (geoip):
    - Update geoip and geoip6 to the September 3 2015 Maxmind GeoLite2
      Country database.

  o Minor features (hidden services):
    - Relays need to have the Fast flag to get the HSDir flag. As this
      is being written, we'll go from 2745 HSDirs down to 2342, a ~14%
      drop. This change should make some attacks against the hidden
      service directory system harder. Fixes ticket 15963.
    - Turn on hidden service statistics collection by setting the torrc
      option HiddenServiceStatistics to "1" by default. (This keeps
      track only of the fraction of traffic used by hidden services, and
      the total number of hidden services in existence.) Closes
      ticket 15254.
    - Client now uses an introduction point failure cache to know when
      to fetch or keep a descriptor in their cache. Previously, failures
      were recorded implicitly, but not explicitly remembered. Closes
      ticket 16389.

  o Minor features (testing, authorities, documentation):
    - New TestingDirAuthVote{Exit,Guard,HSDir}IsStrict flags to
      explicitly manage consensus flags in testing networks. Patch by
      "robgjansen", modified by "teor". Implements part of ticket 14882.

  o Minor bugfixes (security, exit policies):
    - ExitPolicyRejectPrivate now also rejects the relay's published
      IPv6 address (if any), and any publicly routable IPv4 or IPv6
      addresses on any local interfaces. ticket 17027. Patch by "teor".
      Fixes bug 17027; bugfix on 0.2.0.11-alpha.

  o Minor bug fixes (torrc exit policies):
    - In torrc, "accept6 *" and "reject6 *" ExitPolicy lines now only
      produce IPv6 wildcard addresses. Previously they would produce
      both IPv4 and IPv6 wildcard addresses. Patch by "teor". Fixes part
      of bug 16069; bugfix on 0.2.4.7-alpha.
    - When parsing torrc ExitPolicies, we now warn for a number of cases
      where the user's intent is likely to differ from Tor's actual
      behavior. These include: using an IPv4 address with an accept6 or
      reject6 line; using "private" on an accept6 or reject6 line; and
      including any ExitPolicy lines after accept *:* or reject *:*.
      Related to ticket 16069.
    - When parsing torrc ExitPolicies, we now issue an info-level
      message when expanding an "accept/reject *" line to include both
      IPv4 and IPv6 wildcard addresses. Related to ticket 16069.
    - In each instance above, usage advice is provided to avoid the
      message. Resolves ticket 16069. Patch by "teor". Fixes part of bug
      16069; bugfix on 0.2.4.7-alpha.

  o Minor bugfixes (authority):
    - Don't assign "HSDir" to a router if it isn't Valid and Running.
      Fixes bug 16524; bugfix on 0.2.7.2-alpha.
    - Downgrade log messages about Ed25519 key issues if they are in old
      cached router descriptors. Fixes part of bug 16286; bugfix
      on 0.2.7.2-alpha.
    - When we find an Ed25519 key issue in a cached descriptor, stop
      saying the descriptor was just "uploaded". Fixes another part of
      bug 16286; bugfix on 0.2.7.2-alpha.

  o Minor bugfixes (control port):
    - Repair a warning and a spurious result when getting the maximum
      number of file descriptors from the controller. Fixes bug 16697;
      bugfix on 0.2.7.2-alpha.

  o Minor bugfixes (correctness):
    - When calling channel_free_list(), avoid calling smartlist_remove()
      while inside a FOREACH loop. This partially reverts commit
      17356fe7fd96af where the correct SMARTLIST_DEL_CURRENT was
      incorrectly removed. Fixes bug 16924; bugfix on 0.2.4.4-alpha.

  o Minor bugfixes (documentation):
    - Advise users on how to configure separate IPv4 and IPv6 exit
      policies in the manpage and sample torrcs. Related to ticket 16069.
    - Fix the usage message of tor-resolve(1) so that it no longer lists
      the removed -F option. Fixes bug 16913; bugfix on 0.2.2.28-beta.
    - Fix an error in the manual page and comments for
      TestingDirAuthVoteHSDir[IsStrict], which suggested that a HSDir
      required "ORPort connectivity". While this is true, it is in no
      way unique to the HSDir flag. Of all the flags, only HSDirs need a
      DirPort configured in order for the authorities to assign that
      particular flag. Patch by "teor". Fixed as part of 14882; bugfix
      on 0.2.6.3-alpha.

  o Minor bugfixes (Ed25519):
    - Fix a memory leak when reading router descriptors with expired
      Ed25519 certificates. Fixes bug 16539; bugfix on 0.2.7.2-alpha.

  o Minor bugfixes (linux seccomp2 sandbox):
    - Allow bridge authorities to run correctly under the seccomp2
      sandbox. Fixes bug 16964; bugfix on 0.2.5.1-alpha.
    - Allow routers with ed25519 keys to run correctly under the
      seccomp2 sandbox. Fixes bug 16965; bugfix on 0.2.7.2-alpha.

  o Minor bugfixes (open file limit):
    - Fix set_max_file_descriptors() to set by default the max open file
      limit to the current limit when setrlimit() fails. Fixes bug
      16274; bugfix on 0.2.0.10-alpha. Patch by dgoulet.

  o Minor bugfixes (portability):
    - Try harder to normalize the exit status of the Tor process to the
      standard-provided range. Fixes bug 16975; bugfix on every version
      of Tor ever.
    - Check correctly for Windows socket errors in the workqueue
      backend. Fixes bug 16741; bugfix on 0.2.6.3-alpha.
    - Fix the behavior of crypto_rand_time_range() when told to consider
      times before 1970. (These times were possible when running in a
      simulated network environment where time()'s output starts at
      zero.) Fixes bug 16980; bugfix on 0.2.7.1-alpha.
    - Restore correct operation of TLS client-cipher detection on
      OpenSSL 1.1. Fixes bug 14047; bugfix on 0.2.7.2-alpha.

  o Minor bugfixes (relay):
    - Ensure that worker threads actually exit when a fatal error or
      shutdown is indicated. This fix doesn't currently affect the
      behavior of Tor, because Tor workers never indicates fatal error
      or shutdown except in the unit tests. Fixes bug 16868; bugfix
      on 0.2.6.3-alpha.
    - Unblock threads before releasing the work queue mutex to ensure
      predictable scheduling behavior. Fixes bug 16644; bugfix
      on 0.2.6.3-alpha.

  o Code simplification and refactoring:
    - Change the function that's called when we need to retry all
      downloads so that it only reschedules the downloads to happen
      immediately, rather than launching them all at once itself. This
      further simplifies Tor's callgraph.
    - Move some format-parsing functions out of crypto.c and
      crypto_curve25519.c into crypto_format.c and/or util_format.c.
    - Move the client-only parts of init_keys() into a separate
      function. Closes ticket 16763.
    - Simplify the microdesc_free() implementation so that it no longer
      appears (to code analysis tools) to potentially invoke a huge
      suite of other microdesc functions.
    - Simply the control graph further by deferring the inner body of
      directory_all_unreachable() into a callback. Closes ticket 16762.
    - Treat the loss of an owning controller as equivalent to a SIGTERM
      signal. This removes a tiny amount of duplicated code, and
      simplifies our callgraph. Closes ticket 16788.
    - When generating an event to send to the controller, we no longer
      put the event over the network immediately. Instead, we queue
      these events, and use a Libevent callback to deliver them. This
      change simplifies Tor's callgraph by reducing the number of
      functions from which all other Tor functions are reachable. Closes
      ticket 16695.
    - Wrap Windows-only C files inside '#ifdef _WIN32' so that tools
      that try to scan or compile every file on Unix won't decide that
      they are broken.
    - Remove the unused "nulterminate" argument from buf_pullup().

  o Documentation:
    - Recommend a 40 GB example AccountingMax in torrc.sample rather
      than a 4 GB max. Closes ticket 16742.
    - Include the TUNING document in our source tarball. It is referred
      to in the ChangeLog and an error message. Fixes bug 16929; bugfix
      on 0.2.6.1-alpha.

  o Removed code:
    - The internal pure-C tor-fw-helper tool is now removed from the Tor
      distribution, in favor of the pure-Go clone available from
      https://gitweb.torproject.org/tor-fw-helper.git/ . The libraries
      used by the C tor-fw-helper are not, in our opinion, very
      confidence- inspiring in their secure-programming techniques.
      Closes ticket 13338.
    - Remove the code that would try to aggressively flush controller
      connections while writing to them. This code was introduced in
      0.1.2.7-alpha, in order to keep output buffers from exceeding
      their limits. But there is no longer a maximum output buffer size,
      and flushing data in this way caused some undesirable recursions
      in our call graph. Closes ticket 16480.

  o Testing:
    - Make "bridges+hs" the default test network. This tests almost all
      tor functionality during make test-network, while allowing tests
      to succeed on non-IPv6 systems. Requires chutney commit 396da92 in
      test-network-bridges-hs. Closes tickets 16945 (tor) and 16946
      (chutney). Patches by "teor".
    - Autodetect CHUTNEY_PATH if the chutney and Tor sources are side-
      by-side in the same parent directory. Closes ticket 16903. Patch
      by "teor".
    - Use environment variables rather than autoconf substitutions to
      send variables from the build system to the test scripts. This
      change should be easier to maintain, and cause 'make distcheck' to
      work better than before. Fixes bug 17148.
    - Add a new set of callgraph analysis scripts that use clang to
      produce a list of which Tor functions are reachable from which
      other Tor functions. We're planning to use these to help simplify
      our code structure by identifying illogical dependencies.
    - Add new 'test-full' and 'test-full-online' targets to run all
      tests, including integration tests with stem and chutney.
    - Make the test-workqueue test work on Windows by initializing the
      network before we begin.
    - New make target (make test-network-all) to run multiple applicable
      chutney test cases. Patch from Teor; closes 16953.
    - Unit test dns_resolve(), dns_clip_ttl() and dns_get_expiry_ttl()
      functions in dns.c. Implements a portion of ticket 16831.
    - When building Tor with testing coverage enabled, run Chutney tests
      (if any) using the 'tor-cov' coverage binary.
    - When running test-network or test-stem, check for the absence of
      stem/chutney before doing any build operations.


Changes in version 0.2.7.2-alpha - 2015-07-27
  This, the second alpha in the Tor 0.2.7 series, has a number of new
  features, including a way to manually pick the number of introduction
  points for hidden services, and the much stronger Ed25519 signing key
  algorithm for regular Tor relays (including support for encrypted
  offline identity keys in the new algorithm).

  Support for Ed25519 on relays is currently limited to signing router
  descriptors; later alphas in this series will extend Ed25519 key
  support to more parts of the Tor protocol.

  o Major features (Ed25519 identity keys, Proposal 220):
    - All relays now maintain a stronger identity key, using the Ed25519
      elliptic curve signature format. This master key is designed so
      that it can be kept offline. Relays also generate an online
      signing key, and a set of other Ed25519 keys and certificates.
      These are all automatically regenerated and rotated as needed.
      Implements part of ticket 12498.
    - Directory authorities now vote on Ed25519 identity keys along with
      RSA1024 keys. Implements part of ticket 12498.
    - Directory authorities track which Ed25519 identity keys have been
      used with which RSA1024 identity keys, and do not allow them to
      vary freely. Implements part of ticket 12498.
    - Microdescriptors now include Ed25519 identity keys. Implements
      part of ticket 12498.
    - Add support for offline encrypted Ed25519 master keys. To use this
      feature on your tor relay, run "tor --keygen" to make a new master
      key (or to make a new signing key if you already have a master
      key). Closes ticket 13642.

  o Major features (Hidden services):
    - Add the torrc option HiddenServiceNumIntroductionPoints, to
      specify a fixed number of introduction points. Its maximum value
      is 10 and default is 3. Using this option can increase a hidden
      service's reliability under load, at the cost of making it more
      visible that the hidden service is facing extra load. Closes
      ticket 4862.
    - Remove the adaptive algorithm for choosing the number of
      introduction points, which used to change the number of
      introduction points (poorly) depending on the number of
      connections the HS sees. Closes ticket 4862.

  o Major features (onion key cross-certification):
    - Relay descriptors now include signatures of their own identity
      keys, made using the TAP and ntor onion keys. These signatures
      allow relays to prove ownership of their own onion keys. Because
      of this change, microdescriptors will no longer need to include
      RSA identity keys. Implements proposal 228; closes ticket 12499.

  o Major features (performance):
    - Improve the runtime speed of Ed25519 operations by using the
      public-domain Ed25519-donna by Andrew M. ("floodyberry").
      Implements ticket 16467.
    - Improve the runtime speed of the ntor handshake by using an
      optimized curve25519 basepoint scalarmult implementation from the
      public-domain Ed25519-donna by Andrew M. ("floodyberry"), based on
      ideas by Adam Langley. Implements ticket 9663.

  o Major bugfixes (client-side privacy, also in 0.2.6.9):
    - Properly separate out each SOCKSPort when applying stream
      isolation. The error occurred because each port's session group
      was being overwritten by a default value when the listener
      connection was initialized. Fixes bug 16247; bugfix on
      0.2.6.3-alpha. Patch by "jojelino".

  o Major bugfixes (hidden service clients, stability, also in 0.2.6.10):
    - Stop refusing to store updated hidden service descriptors on a
      client. This reverts commit 9407040c59218 (which indeed fixed bug
      14219, but introduced a major hidden service reachability
      regression detailed in bug 16381). This is a temporary fix since
      we can live with the minor issue in bug 14219 (it just results in
      some load on the network) but the regression of 16381 is too much
      of a setback. First-round fix for bug 16381; bugfix
      on 0.2.6.3-alpha.

  o Major bugfixes (hidden services):
    - When cannibalizing a circuit for an introduction point, always
      extend to the chosen exit node (creating a 4 hop circuit).
      Previously Tor would use the current circuit exit node, which
      changed the original choice of introduction point, and could cause
      the hidden service to skip excluded introduction points or
      reconnect to a skipped introduction point. Fixes bug 16260; bugfix
      on 0.1.0.1-rc.

  o Major bugfixes (open file limit):
    - The open file limit wasn't checked before calling
      tor_accept_socket_nonblocking(), which would make Tor exceed the
      limit. Now, before opening a new socket, Tor validates the open
      file limit just before, and if the max has been reached, return an
      error. Fixes bug 16288; bugfix on 0.1.1.1-alpha.

  o Major bugfixes (stability, also in 0.2.6.10):
    - Stop crashing with an assertion failure when parsing certain kinds
      of malformed or truncated microdescriptors. Fixes bug 16400;
      bugfix on 0.2.6.1-alpha. Found by "torkeln"; fix based on a patch
      by "cypherpunks_backup".
    - Stop random client-side assertion failures that could occur when
      connecting to a busy hidden service, or connecting to a hidden
      service while a NEWNYM is in progress. Fixes bug 16013; bugfix
      on 0.1.0.1-rc.

  o Minor features (directory authorities, security, also in 0.2.6.9):
    - The HSDir flag given by authorities now requires the Stable flag.
      For the current network, this results in going from 2887 to 2806
      HSDirs. Also, it makes it harder for an attacker to launch a sybil
      attack by raising the effort for a relay to become Stable to
      require at the very least 7 days, while maintaining the 96 hours
      uptime requirement for HSDir. Implements ticket 8243.

  o Minor features (client):
    - Relax the validation of hostnames in SOCKS5 requests, allowing the
      character '_' to appear, in order to cope with domains observed in
      the wild that are serving non-RFC compliant records. Resolves
      ticket 16430.
    - Relax the validation done to hostnames in SOCKS5 requests, and
      allow a single trailing '.' to cope with clients that pass FQDNs
      using that syntax to explicitly indicate that the domain name is
      fully-qualified. Fixes bug 16674; bugfix on 0.2.6.2-alpha.
    - Add GroupWritable and WorldWritable options to unix-socket based
      SocksPort and ControlPort options. These options apply to a single
      socket, and override {Control,Socks}SocketsGroupWritable. Closes
      ticket 15220.

  o Minor features (control protocol):
    - Support network-liveness GETINFO key and NETWORK_LIVENESS event in
      the control protocol. Resolves ticket 15358.

  o Minor features (directory authorities):
    - Directory authorities no longer vote against the "Fast", "Stable",
      and "HSDir" flags just because they were going to vote against
      "Running": if the consensus turns out to be that the router was
      running, then the authority's vote should count. Patch from Peter
      Retzlaff; closes issue 8712.

  o Minor features (geoip, also in 0.2.6.10):
    - Update geoip to the June 3 2015 Maxmind GeoLite2 Country database.
    - Update geoip6 to the June 3 2015 Maxmind GeoLite2 Country database.

  o Minor features (hidden services):
    - Add the new options "HiddenServiceMaxStreams" and
      "HiddenServiceMaxStreamsCloseCircuit" to allow hidden services to
      limit the maximum number of simultaneous streams per circuit, and
      optionally tear down the circuit when the limit is exceeded. Part
      of ticket 16052.

  o Minor features (portability):
    - Use C99 variadic macros when the compiler is not GCC. This avoids
      failing compilations on MSVC, and fixes a log-file-based race
      condition in our old workarounds. Original patch from Gisle Vanem.

  o Minor bugfixes (compilation, also in 0.2.6.9):
    - Build with --enable-systemd correctly when libsystemd is
      installed, but systemd is not. Fixes bug 16164; bugfix on
      0.2.6.3-alpha. Patch from Peter Palfrader.

  o Minor bugfixes (controller):
    - Add the descriptor ID in each HS_DESC control event. It was
      missing, but specified in control-spec.txt. Fixes bug 15881;
      bugfix on 0.2.5.2-alpha.

  o Minor bugfixes (crypto error-handling, also in 0.2.6.10):
    - Check for failures from crypto_early_init, and refuse to continue.
      A previous typo meant that we could keep going with an
      uninitialized crypto library, and would have OpenSSL initialize
      its own PRNG. Fixes bug 16360; bugfix on 0.2.5.2-alpha, introduced
      when implementing ticket 4900. Patch by "teor".

  o Minor bugfixes (hidden services):
    - Fix a crash when reloading configuration while at least one
      configured and one ephemeral hidden service exists. Fixes bug
      16060; bugfix on 0.2.7.1-alpha.
    - Avoid crashing with a double-free bug when we create an ephemeral
      hidden service but adding it fails for some reason. Fixes bug
      16228; bugfix on 0.2.7.1-alpha.

  o Minor bugfixes (Linux seccomp2 sandbox):
    - Use the sandbox in tor_open_cloexec whether or not O_CLOEXEC is
      defined. Patch by "teor". Fixes bug 16515; bugfix on 0.2.3.1-alpha.

  o Minor bugfixes (Linux seccomp2 sandbox, also in 0.2.6.10):
    - Allow pipe() and pipe2() syscalls in the seccomp2 sandbox: we need
      these when eventfd2() support is missing. Fixes bug 16363; bugfix
      on 0.2.6.3-alpha. Patch from "teor".

  o Minor bugfixes (Linux seccomp2 sandbox, also in 0.2.6.9):
    - Fix sandboxing to work when running as a relay, by allowing the
      renaming of secret_id_key, and allowing the eventfd2 and futex
      syscalls. Fixes bug 16244; bugfix on 0.2.6.1-alpha. Patch by
      Peter Palfrader.
    - Allow systemd connections to work with the Linux seccomp2 sandbox
      code. Fixes bug 16212; bugfix on 0.2.6.2-alpha. Patch by
      Peter Palfrader.

  o Minor bugfixes (relay):
    - Fix a rarely-encountered memory leak when failing to initialize
      the thread pool. Fixes bug 16631; bugfix on 0.2.6.3-alpha. Patch
      from "cypherpunks".

  o Minor bugfixes (systemd):
    - Fix an accidental formatting error that broke the systemd
      configuration file. Fixes bug 16152; bugfix on 0.2.7.1-alpha.
    - Tor's systemd unit file no longer contains extraneous spaces.
      These spaces would sometimes confuse tools like deb-systemd-
      helper. Fixes bug 16162; bugfix on 0.2.5.5-alpha.

  o Minor bugfixes (tests):
    - Use the configured Python executable when running test-stem-full.
      Fixes bug 16470; bugfix on 0.2.7.1-alpha.

  o Minor bugfixes (tests, also in 0.2.6.9):
    - Fix a crash in the unit tests when built with MSVC2013. Fixes bug
      16030; bugfix on 0.2.6.2-alpha. Patch from "NewEraCracker".

  o Minor bugfixes (threads, comments):
    - Always initialize return value in compute_desc_id in rendcommon.c
      Patch by "teor". Fixes part of bug 16115; bugfix on 0.2.7.1-alpha.
    - Check for NULL values in getinfo_helper_onions(). Patch by "teor".
      Fixes part of bug 16115; bugfix on 0.2.7.1-alpha.
    - Remove undefined directive-in-macro in test_util_writepid clang
      3.7 complains that using a preprocessor directive inside a macro
      invocation in test_util_writepid in test_util.c is undefined.
      Patch by "teor". Fixes part of bug 16115; bugfix on 0.2.7.1-alpha.

  o Code simplification and refactoring:
    - Define WINVER and _WIN32_WINNT centrally, in orconfig.h, in order
      to ensure they remain consistent and visible everywhere.
    - Remove some vestigial workarounds for the MSVC6 compiler. We
      haven't supported that in ages.
    - The link authentication code has been refactored for better
      testability and reliability. It now uses code generated with the
      "trunnel" binary encoding generator, to reduce the risk of bugs
      due to programmer error. Done as part of ticket 12498.

  o Documentation:
    - Include a specific and (hopefully) accurate documentation of the
      torrc file's meta-format in doc/torrc_format.txt. This is mainly
      of interest to people writing programs to parse or generate torrc
      files. This document is not a commitment to long-term
      compatibility; some aspects of the current format are a bit
      ridiculous. Closes ticket 2325.

  o Removed features:
    - Tor no longer supports copies of OpenSSL that are missing support
      for Elliptic Curve Cryptography. (We began using ECC when
      available in 0.2.4.8-alpha, for more safe and efficient key
      negotiation.) In particular, support for at least one of P256 or
      P224 is now required, with manual configuration needed if only
      P224 is available. Resolves ticket 16140.
    - Tor no longer supports versions of OpenSSL before 1.0. (If you are
      on an operating system that has not upgraded to OpenSSL 1.0 or
      later, and you compile Tor from source, you will need to install a
      more recent OpenSSL to link Tor against.) These versions of
      OpenSSL are still supported by the OpenSSL, but the numerous
      cryptographic improvements in later OpenSSL releases makes them a
      clear choice. Resolves ticket 16034.
    - Remove the HidServDirectoryV2 option. Now all relays offer to
      store hidden service descriptors. Related to 16543.
    - Remove the VoteOnHidServDirectoriesV2 option, since all
      authorities have long set it to 1. Closes ticket 16543.

  o Testing:
    - Document use of coverity, clang static analyzer, and clang dynamic
      undefined behavior and address sanitizers in doc/HACKING. Include
      detailed usage instructions in the blacklist. Patch by "teor".
      Closes ticket 15817.
    - The link authentication protocol code now has extensive tests.
    - The relay descriptor signature testing code now has
      extensive tests.
    - The test_workqueue program now runs faster, and is enabled by
      default as a part of "make check".
    - Now that OpenSSL has its own scrypt implementation, add an unit
      test that checks for interoperability between libscrypt_scrypt()
      and OpenSSL's EVP_PBE_scrypt() so that we could not use libscrypt
      and rely on EVP_PBE_scrypt() whenever possible. Resolves
      ticket 16189.


Changes in version 0.2.6.10 - 2015-07-12
  Tor version 0.2.6.10 fixes some significant stability and hidden
  service client bugs, bulletproofs the cryptography init process, and
  fixes a bug when using the sandbox code with some older versions of
  Linux. Everyone running an older version, especially an older version
  of 0.2.6, should upgrade.

  o Major bugfixes (hidden service clients, stability):
    - Stop refusing to store updated hidden service descriptors on a
      client. This reverts commit 9407040c59218 (which indeed fixed bug
      14219, but introduced a major hidden service reachability
      regression detailed in bug 16381). This is a temporary fix since
      we can live with the minor issue in bug 14219 (it just results in
      some load on the network) but the regression of 16381 is too much
      of a setback. First-round fix for bug 16381; bugfix
      on 0.2.6.3-alpha.

  o Major bugfixes (stability):
    - Stop crashing with an assertion failure when parsing certain kinds
      of malformed or truncated microdescriptors. Fixes bug 16400;
      bugfix on 0.2.6.1-alpha. Found by "torkeln"; fix based on a patch
      by "cypherpunks_backup".
    - Stop random client-side assertion failures that could occur when
      connecting to a busy hidden service, or connecting to a hidden
      service while a NEWNYM is in progress. Fixes bug 16013; bugfix
      on 0.1.0.1-rc.

  o Minor features (geoip):
    - Update geoip to the June 3 2015 Maxmind GeoLite2 Country database.
    - Update geoip6 to the June 3 2015 Maxmind GeoLite2 Country database.

  o Minor bugfixes (crypto error-handling):
    - Check for failures from crypto_early_init, and refuse to continue.
      A previous typo meant that we could keep going with an
      uninitialized crypto library, and would have OpenSSL initialize
      its own PRNG. Fixes bug 16360; bugfix on 0.2.5.2-alpha, introduced
      when implementing ticket 4900. Patch by "teor".

  o Minor bugfixes (Linux seccomp2 sandbox):
    - Allow pipe() and pipe2() syscalls in the seccomp2 sandbox: we need
      these when eventfd2() support is missing. Fixes bug 16363; bugfix
      on 0.2.6.3-alpha. Patch from "teor".


Changes in version 0.2.6.9 - 2015-06-11
  Tor 0.2.6.9 fixes a regression in the circuit isolation code, increases the
  requirements for receiving an HSDir flag, and addresses some other small
  bugs in the systemd and sandbox code. Clients using circuit isolation
  should upgrade; all directory authorities should upgrade.

  o Major bugfixes (client-side privacy):
    - Properly separate out each SOCKSPort when applying stream
      isolation. The error occurred because each port's session group was
      being overwritten by a default value when the listener connection
      was initialized. Fixes bug 16247; bugfix on 0.2.6.3-alpha. Patch
      by "jojelino".

  o Minor feature (directory authorities, security):
    - The HSDir flag given by authorities now requires the Stable flag.
      For the current network, this results in going from 2887 to 2806
      HSDirs. Also, it makes it harder for an attacker to launch a sybil
      attack by raising the effort for a relay to become Stable which
      takes at the very least 7 days to do so and by keeping the 96
      hours uptime requirement for HSDir. Implements ticket 8243.

  o Minor bugfixes (compilation):
    - Build with --enable-systemd correctly when libsystemd is
      installed, but systemd is not. Fixes bug 16164; bugfix on
      0.2.6.3-alpha. Patch from Peter Palfrader.

  o Minor bugfixes (Linux seccomp2 sandbox):
    - Fix sandboxing to work when running as a relaymby renaming of
      secret_id_key, and allowing the eventfd2 and futex syscalls. Fixes
      bug 16244; bugfix on 0.2.6.1-alpha. Patch by Peter Palfrader.
    - Allow systemd connections to work with the Linux seccomp2 sandbox
      code. Fixes bug 16212; bugfix on 0.2.6.2-alpha. Patch by
      Peter Palfrader.

  o Minor bugfixes (tests):
    - Fix a crash in the unit tests when built with MSVC2013. Fixes bug
      16030; bugfix on 0.2.6.2-alpha. Patch from "NewEraCracker".


Changes in version 0.2.6.8 - 2015-05-21
  Tor 0.2.6.8 fixes a bit of dodgy code in parsing INTRODUCE2 cells, and
  fixes an authority-side bug in assigning the HSDir flag. All directory
  authorities should upgrade.

  o Major bugfixes (hidden services, backport from 0.2.7.1-alpha):
    - Revert commit that made directory authorities assign the HSDir
      flag to relays without a DirPort; this was bad because such relays
      can't handle BEGIN_DIR cells. Fixes bug 15850; bugfix
      on 0.2.6.3-alpha.

  o Minor bugfixes (hidden service, backport from 0.2.7.1-alpha):
    - Fix an out-of-bounds read when parsing invalid INTRODUCE2 cells on
      a client authorized hidden service. Fixes bug 15823; bugfix
      on 0.2.1.6-alpha.

  o Minor features (geoip):
    - Update geoip to the April 8 2015 Maxmind GeoLite2 Country database.
    - Update geoip6 to the April 8 2015 Maxmind GeoLite2
      Country database.


Changes in version 0.2.7.1-alpha - 2015-05-12
  Tor 0.2.7.1-alpha is the first alpha release in its series. It
  includes numerous small features and bugfixes against previous Tor
  versions, and numerous small infrastructure improvements. The most
  notable features are several new ways for controllers to interact with
  the hidden services subsystem.

  o New system requirements:
    - Tor no longer includes workarounds to support Libevent versions
      before 1.3e. Libevent 2.0 or later is recommended. Closes
      ticket 15248.

  o Major features (controller):
    - Add the ADD_ONION and DEL_ONION commands that allow the creation
      and management of hidden services via the controller. Closes
      ticket 6411.
    - New "GETINFO onions/current" and "GETINFO onions/detached"
      commands to get information about hidden services created via the
      controller. Part of ticket 6411.
    - New HSFETCH command to launch a request for a hidden service
      descriptor. Closes ticket 14847.
    - New HSPOST command to upload a hidden service descriptor. Closes
      ticket 3523. Patch by "DonnchaC".

  o Major bugfixes (hidden services):
    - Revert commit that made directory authorities assign the HSDir
      flag to relays without a DirPort; this was bad because such relays
      can't handle BEGIN_DIR cells. Fixes bug 15850; bugfix
      on 0.2.6.3-alpha.

  o Minor features (clock-jump tolerance):
    - Recover better when our clock jumps back many hours, like might
      happen for Tails or Whonix users who start with a very wrong
      hardware clock, use Tor to discover a more accurate time, and then
      fix their clock. Resolves part of ticket 8766.

  o Minor features (command-line interface):
    - Make --hash-password imply --hush to prevent unnecessary noise.
      Closes ticket 15542. Patch from "cypherpunks".
    - Print a warning whenever we find a relative file path being used
      as torrc option. Resolves issue 14018.

  o Minor features (controller):
    - Add DirAuthority lines for default directory authorities to the
      output of the "GETINFO config/defaults" command if not already
      present. Implements ticket 14840.
    - Controllers can now use "GETINFO hs/client/desc/id/..." to
      retrieve items from the client's hidden service descriptor cache.
      Closes ticket 14845.
    - Implement a new controller command "GETINFO status/fresh-relay-
      descs" to fetch a descriptor/extrainfo pair that was generated on
      demand just for the controller's use. Implements ticket 14784.

  o Minor features (DoS-resistance):
    - Make it harder for attackers to overload hidden services with
      introductions, by blocking multiple introduction requests on the
      same circuit. Resolves ticket 15515.

  o Minor features (geoip):
    - Update geoip to the April 8 2015 Maxmind GeoLite2 Country database.
    - Update geoip6 to the April 8 2015 Maxmind GeoLite2
      Country database.

  o Minor features (HS popularity countermeasure):
    - To avoid leaking HS popularity, don't cycle the introduction point
      when we've handled a fixed number of INTRODUCE2 cells but instead
      cycle it when a random number of introductions is reached, thus
      making it more difficult for an attacker to find out the amount of
      clients that have used the introduction point for a specific HS.
      Closes ticket 15745.

  o Minor features (logging):
    - Include the Tor version in all LD_BUG log messages, since people
      tend to cut and paste those into the bugtracker. Implements
      ticket 15026.

  o Minor features (pluggable transports):
    - When launching managed pluggable transports on Linux systems,
      attempt to have the kernel deliver a SIGTERM on tor exit if the
      pluggable transport process is still running. Resolves
      ticket 15471.
    - When launching managed pluggable transports, setup a valid open
      stdin in the child process that can be used to detect if tor has
      terminated. The "TOR_PT_EXIT_ON_STDIN_CLOSE" environment variable
      can be used by implementations to detect this new behavior.
      Resolves ticket 15435.

  o Minor features (testing):
    - Add a test to verify that the compiler does not eliminate our
      memwipe() implementation. Closes ticket 15377.
    - Add make rule `check-changes` to verify the format of changes
      files. Closes ticket 15180.
    - Add unit tests for control_event_is_interesting(). Add a compile-
      time check that the number of events doesn't exceed the capacity
      of control_event_t.event_mask. Closes ticket 15431, checks for
      bugs similar to 13085. Patch by "teor".
    - Command-line argument tests moved to Stem. Resolves ticket 14806.
    - Integrate the ntor, backtrace, and zero-length keys tests into the
      automake test suite. Closes ticket 15344.
    - Remove assertions during builds to determine Tor's test coverage.
      We don't want to trigger these even in assertions, so including
      them artificially makes our branch coverage look worse than it is.
      This patch provides the new test-stem-full and coverage-html-full
      configure options. Implements ticket 15400.

  o Minor bugfixes (build):
    - Improve out-of-tree builds by making non-standard rules work and
      clean up additional files and directories. Fixes bug 15053; bugfix
      on 0.2.7.0-alpha.

  o Minor bugfixes (command-line interface):
    - When "--quiet" is provided along with "--validate-config", do not
      write anything to stdout on success. Fixes bug 14994; bugfix
      on 0.2.3.3-alpha.
    - When complaining about bad arguments to "--dump-config", use
      stderr, not stdout.

  o Minor bugfixes (configuration, unit tests):
    - Only add the default fallback directories when the DirAuthorities,
      AlternateDirAuthority, and FallbackDir directory config options
      are set to their defaults. The default fallback directory list is
      currently empty, this fix will only change tor's behavior when it
      has default fallback directories. Includes unit tests for
      consider_adding_dir_servers(). Fixes bug 15642; bugfix on
      90f6071d8dc0 in 0.2.4.7-alpha. Patch by "teor".

  o Minor bugfixes (correctness):
    - For correctness, avoid modifying a constant string in
      handle_control_postdescriptor. Fixes bug 15546; bugfix
      on 0.1.1.16-rc.
    - Remove side-effects from tor_assert() calls. This was harmless,
      because we never disable assertions, but it is bad style and
      unnecessary. Fixes bug 15211; bugfix on 0.2.5.5, 0.2.2.36,
      and 0.2.0.10.

  o Minor bugfixes (hidden service):
    - Fix an out-of-bounds read when parsing invalid INTRODUCE2 cells on
      a client authorized hidden service. Fixes bug 15823; bugfix
      on 0.2.1.6-alpha.
    - Remove an extraneous newline character from the end of hidden
      service descriptors. Fixes bug 15296; bugfix on 0.2.0.10-alpha.

  o Minor bugfixes (interface):
    - Print usage information for --dump-config when it is used without
      an argument. Also, fix the error message to use different wording
      and add newline at the end. Fixes bug 15541; bugfix
      on 0.2.5.1-alpha.

  o Minor bugfixes (logs):
    - When building Tor under Clang, do not include an extra set of
      parentheses in log messages that include function names. Fixes bug
      15269; bugfix on every released version of Tor when compiled with
      recent enough Clang.

  o Minor bugfixes (network):
    - When attempting to use fallback technique for network interface
      lookup, disregard loopback and multicast addresses since they are
      unsuitable for public communications.

  o Minor bugfixes (statistics):
    - Disregard the ConnDirectionStatistics torrc options when Tor is
      not a relay since in that mode of operation no sensible data is
      being collected and because Tor might run into measurement hiccups
      when running as a client for some time, then becoming a relay.
      Fixes bug 15604; bugfix on 0.2.2.35.

  o Minor bugfixes (test networks):
    - When self-testing reachability, use ExtendAllowPrivateAddresses to
      determine if local/private addresses imply reachability. The
      previous fix used TestingTorNetwork, which implies
      ExtendAllowPrivateAddresses, but this excluded rare configurations
      where ExtendAllowPrivateAddresses is set but TestingTorNetwork is
      not. Fixes bug 15771; bugfix on 0.2.6.1-alpha. Patch by "teor",
      issue discovered by CJ Ess.

  o Minor bugfixes (testing):
    - Check for matching value in server response in ntor_ref.py. Fixes
      bug 15591; bugfix on 0.2.4.8-alpha. Reported and fixed
      by "joelanders".
    - Set the severity correctly when testing
      get_interface_addresses_ifaddrs() and
      get_interface_addresses_win32(), so that the tests fail gracefully
      instead of triggering an assertion. Fixes bug 15759; bugfix on
      0.2.6.3-alpha. Reported by Nicolas Derive.

  o Code simplification and refactoring:
    - Move the hacky fallback code out of get_interface_address6() into
      separate function and get it covered with unit-tests. Resolves
      ticket 14710.
    - Refactor hidden service client-side cache lookup to intelligently
      report its various failure cases, and disentangle failure cases
      involving a lack of introduction points. Closes ticket 14391.
    - Use our own Base64 encoder instead of OpenSSL's, to allow more
      control over the output. Part of ticket 15652.

  o Documentation:
    - Improve the descriptions of statistics-related torrc options in
      the manpage to describe rationale and possible uses cases. Fixes
      issue 15550.
    - Improve the layout and formatting of ./configure --help messages.
      Closes ticket 15024. Patch from "cypherpunks".
    - Standardize on the term "server descriptor" in the manual page.
      Previously, we had used "router descriptor", "server descriptor",
      and "relay descriptor" interchangeably. Part of ticket 14987.

  o Removed code:
    - Remove `USE_OPENSSL_BASE64` and the corresponding fallback code
      and always use the internal Base64 decoder. The internal decoder
      has been part of tor since 0.2.0.10-alpha, and no one should
      be using the OpenSSL one. Part of ticket 15652.
    - Remove the 'tor_strclear()' function; use memwipe() instead.
      Closes ticket 14922.

  o Removed features:
    - Remove the (seldom-used) DynamicDHGroups feature. For anti-
      fingerprinting we now recommend pluggable transports; for forward-
      secrecy in TLS, we now use the P-256 group. Closes ticket 13736.
    - Remove the undocumented "--digests" command-line option. It
      complicated our build process, caused subtle build issues on
      multiple platforms, and is now redundant since we started
      including git version identifiers. Closes ticket 14742.
    - Tor no longer contains checks for ancient directory cache versions
      that didn't know about microdescriptors.
    - Tor no longer contains workarounds for stat files generated by
      super-old versions of Tor that didn't choose guards sensibly.


Changes in version 0.2.4.27 - 2015-04-06
  Tor 0.2.4.27 backports two fixes from 0.2.6.7 for security issues that
  could be used by an attacker to crash hidden services, or crash clients
  visiting hidden services. Hidden services should upgrade as soon as
  possible; clients should upgrade whenever packages become available.

  This release also backports a simple improvement to make hidden
  services a bit less vulnerable to denial-of-service attacks.

  o Major bugfixes (security, hidden service):
    - Fix an issue that would allow a malicious client to trigger an
      assertion failure and halt a hidden service. Fixes bug 15600;
      bugfix on 0.2.1.6-alpha. Reported by "disgleirio".
    - Fix a bug that could cause a client to crash with an assertion
      failure when parsing a malformed hidden service descriptor. Fixes
      bug 15601; bugfix on 0.2.1.5-alpha. Found by "DonnchaC".

  o Minor features (DoS-resistance, hidden service):
    - Introduction points no longer allow multiple INTRODUCE1 cells to
      arrive on the same circuit. This should make it more expensive for
      attackers to overwhelm hidden services with introductions.
      Resolves ticket 15515.


Changes in version 0.2.5.12 - 2015-04-06
  Tor 0.2.5.12 backports two fixes from 0.2.6.7 for security issues that
  could be used by an attacker to crash hidden services, or crash clients
  visiting hidden services. Hidden services should upgrade as soon as
  possible; clients should upgrade whenever packages become available.

  This release also backports a simple improvement to make hidden
  services a bit less vulnerable to denial-of-service attacks.

  o Major bugfixes (security, hidden service):
    - Fix an issue that would allow a malicious client to trigger an
      assertion failure and halt a hidden service. Fixes bug 15600;
      bugfix on 0.2.1.6-alpha. Reported by "disgleirio".
    - Fix a bug that could cause a client to crash with an assertion
      failure when parsing a malformed hidden service descriptor. Fixes
      bug 15601; bugfix on 0.2.1.5-alpha. Found by "DonnchaC".

  o Minor features (DoS-resistance, hidden service):
    - Introduction points no longer allow multiple INTRODUCE1 cells to
      arrive on the same circuit. This should make it more expensive for
      attackers to overwhelm hidden services with introductions.
      Resolves ticket 15515.


Changes in version 0.2.6.7 - 2015-04-06
  Tor 0.2.6.7 fixes two security issues that could be used by an
  attacker to crash hidden services, or crash clients visiting hidden
  services. Hidden services should upgrade as soon as possible; clients
  should upgrade whenever packages become available.

  This release also contains two simple improvements to make hidden
  services a bit less vulnerable to denial-of-service attacks.

  o Major bugfixes (security, hidden service):
    - Fix an issue that would allow a malicious client to trigger an
      assertion failure and halt a hidden service. Fixes bug 15600;
      bugfix on 0.2.1.6-alpha. Reported by "disgleirio".
    - Fix a bug that could cause a client to crash with an assertion
      failure when parsing a malformed hidden service descriptor. Fixes
      bug 15601; bugfix on 0.2.1.5-alpha. Found by "DonnchaC".

  o Minor features (DoS-resistance, hidden service):
    - Introduction points no longer allow multiple INTRODUCE1 cells to
      arrive on the same circuit. This should make it more expensive for
      attackers to overwhelm hidden services with introductions.
      Resolves ticket 15515.
    - Decrease the amount of reattempts that a hidden service performs
      when its rendezvous circuits fail. This reduces the computational
      cost for running a hidden service under heavy load. Resolves
      ticket 11447.


Changes in version 0.2.6.6 - 2015-03-24
  Tor 0.2.6.6 is the first stable release in the 0.2.6 series.

  It adds numerous safety, security, correctness, and performance
  improvements. Client programs can be configured to use more kinds of
  sockets, AutomapHosts works better, the multithreading backend is
  improved, cell transmission is refactored, test coverage is much
  higher, more denial-of-service attacks are handled, guard selection is
  improved to handle long-term guards better, pluggable transports
  should work a bit better, and some annoying hidden service performance
  bugs should be addressed.

  o Minor bugfixes (portability):
    - Use the correct datatype in the SipHash-2-4 function to prevent
      compilers from assuming any sort of alignment. Fixes bug 15436;
      bugfix on 0.2.5.3-alpha.

Changes in version 0.2.6.5-rc - 2015-03-18
  Tor 0.2.6.5-rc is the second and (hopefully) last release candidate in
  the 0.2.6. It fixes a small number of bugs found in 0.2.6.4-rc.

  o Major bugfixes (client):
    - Avoid crashing when making certain configuration option changes on
      clients. Fixes bug 15245; bugfix on 0.2.6.3-alpha. Reported
      by "anonym".

  o Major bugfixes (pluggable transports):
    - Initialize the extended OR Port authentication cookie before
      launching pluggable transports. This prevents a race condition
      that occurred when server-side pluggable transports would cache the
      authentication cookie before it has been (re)generated. Fixes bug
      15240; bugfix on 0.2.5.1-alpha.

  o Major bugfixes (portability):
    - Do not crash on startup when running on Solaris. Fixes a bug
      related to our fix for 9495; bugfix on 0.2.6.1-alpha. Reported
      by "ruebezahl".

  o Minor features (heartbeat):
    - On relays, report how many connections we negotiated using each
      version of the Tor link protocols. This information will let us
      know if removing support for very old versions of the Tor
      protocols is harming the network. Closes ticket 15212.

  o Code simplification and refactoring:
    - Refactor main loop to extract the 'loop' part. This makes it
      easier to run Tor under Shadow. Closes ticket 15176.


Changes in version 0.2.5.11 - 2015-03-17
  Tor 0.2.5.11 is the second stable release in the 0.2.5 series.

  It backports several bugfixes from the 0.2.6 branch, including a
  couple of medium-level security fixes for relays and exit nodes.
  It also updates the list of directory authorities.

  o Directory authority changes:
    - Remove turtles as a directory authority.
    - Add longclaw as a new (v3) directory authority. This implements
      ticket 13296. This keeps the directory authority count at 9.
    - The directory authority Faravahar has a new IP address. This
      closes ticket 14487.

  o Major bugfixes (crash, OSX, security):
    - Fix a remote denial-of-service opportunity caused by a bug in
      OSX's _strlcat_chk() function. Fixes bug 15205; bug first appeared
      in OSX 10.9.

  o Major bugfixes (relay, stability, possible security):
    - Fix a bug that could lead to a relay crashing with an assertion
      failure if a buffer of exactly the wrong layout was passed to
      buf_pullup() at exactly the wrong time. Fixes bug 15083; bugfix on
      0.2.0.10-alpha. Patch from 'cypherpunks'.
    - Do not assert if the 'data' pointer on a buffer is advanced to the
      very end of the buffer; log a BUG message instead. Only assert if
      it is past that point. Fixes bug 15083; bugfix on 0.2.0.10-alpha.

  o Major bugfixes (exit node stability):
    - Fix an assertion failure that could occur under high DNS load.
      Fixes bug 14129; bugfix on Tor 0.0.7rc1. Found by "jowr";
      diagnosed and fixed by "cypherpunks".

  o Major bugfixes (Linux seccomp2 sandbox):
    - Upon receiving sighup with the seccomp2 sandbox enabled, do not
      crash during attempts to call wait4. Fixes bug 15088; bugfix on
      0.2.5.1-alpha. Patch from "sanic".

  o Minor features (controller):
    - New "GETINFO bw-event-cache" to get information about recent
      bandwidth events. Closes ticket 14128. Useful for controllers to
      get recent bandwidth history after the fix for ticket 13988.

  o Minor features (geoip):
    - Update geoip to the March 3 2015 Maxmind GeoLite2 Country database.
    - Update geoip6 to the March 3 2015 Maxmind GeoLite2
      Country database.

  o Minor bugfixes (client, automapping):
    - Avoid crashing on torrc lines for VirtualAddrNetworkIPv[4|6] when
      no value follows the option. Fixes bug 14142; bugfix on
      0.2.4.7-alpha. Patch by "teor".
    - Fix a memory leak when using AutomapHostsOnResolve. Fixes bug
      14195; bugfix on 0.1.0.1-rc.

  o Minor bugfixes (compilation):
    - Build without warnings with the stock OpenSSL srtp.h header, which
      has a duplicate declaration of SSL_get_selected_srtp_profile().
      Fixes bug 14220; this is OpenSSL's bug, not ours.

  o Minor bugfixes (directory authority):
    - Allow directory authorities to fetch more data from one another if
      they find themselves missing lots of votes. Previously, they had
      been bumping against the 10 MB queued data limit. Fixes bug 14261;
      bugfix on 0.1.2.5-alpha.
    - Enlarge the buffer to read bwauth generated files to avoid an
      issue when parsing the file in dirserv_read_measured_bandwidths().
      Fixes bug 14125; bugfix on 0.2.2.1-alpha.

  o Minor bugfixes (statistics):
    - Increase period over which bandwidth observations are aggregated
      from 15 minutes to 4 hours. Fixes bug 13988; bugfix on 0.0.8pre1.

  o Minor bugfixes (preventative security, C safety):
    - When reading a hexadecimal, base-32, or base-64 encoded value from
      a string, always overwrite the whole output buffer. This prevents
      some bugs where we would look at (but fortunately, not reveal)
      uninitialized memory on the stack. Fixes bug 14013; bugfix on all
      versions of Tor.


Changes in version 0.2.4.26 - 2015-03-17
  Tor 0.2.4.26 includes an updated list of directory authorities.  It
  also backports a couple of stability and security bugfixes from 0.2.5
  and beyond.

  o Directory authority changes:
    - Remove turtles as a directory authority.
    - Add longclaw as a new (v3) directory authority. This implements
      ticket 13296. This keeps the directory authority count at 9.
    - The directory authority Faravahar has a new IP address. This
      closes ticket 14487.

  o Major bugfixes (exit node stability, also in 0.2.6.3-alpha):
    - Fix an assertion failure that could occur under high DNS load.
      Fixes bug 14129; bugfix on Tor 0.0.7rc1. Found by "jowr";
      diagnosed and fixed by "cypherpunks".

  o Major bugfixes (relay, stability, possible security, also in 0.2.6.4-rc):
    - Fix a bug that could lead to a relay crashing with an assertion
      failure if a buffer of exactly the wrong layout was passed to
      buf_pullup() at exactly the wrong time. Fixes bug 15083; bugfix on
      0.2.0.10-alpha. Patch from 'cypherpunks'.
    - Do not assert if the 'data' pointer on a buffer is advanced to the
      very end of the buffer; log a BUG message instead. Only assert if
      it is past that point. Fixes bug 15083; bugfix on 0.2.0.10-alpha.

  o Minor features (geoip):
    - Update geoip to the March 3 2015 Maxmind GeoLite2 Country database.
    - Update geoip6 to the March 3 2015 Maxmind GeoLite2
      Country database.

Changes in version 0.2.6.4-rc - 2015-03-09
  Tor 0.2.6.4-alpha fixes an issue in the directory code that an
  attacker might be able to use in order to crash certain Tor
  directories. It also resolves some minor issues left over from, or
  introduced in, Tor 0.2.6.3-alpha or earlier.

  o Major bugfixes (crash, OSX, security):
    - Fix a remote denial-of-service opportunity caused by a bug in
      OSX's _strlcat_chk() function. Fixes bug 15205; bug first appeared
      in OSX 10.9.

  o Major bugfixes (relay, stability, possible security):
    - Fix a bug that could lead to a relay crashing with an assertion
      failure if a buffer of exactly the wrong layout is passed to
      buf_pullup() at exactly the wrong time. Fixes bug 15083; bugfix on
      0.2.0.10-alpha. Patch from "cypherpunks".
    - Do not assert if the 'data' pointer on a buffer is advanced to the
      very end of the buffer; log a BUG message instead. Only assert if
      it is past that point. Fixes bug 15083; bugfix on 0.2.0.10-alpha.

  o Major bugfixes (FreeBSD IPFW transparent proxy):
    - Fix address detection with FreeBSD transparent proxies, when
      "TransProxyType ipfw" is in use. Fixes bug 15064; bugfix
      on 0.2.5.4-alpha.

  o Major bugfixes (Linux seccomp2 sandbox):
    - Pass IPPROTO_TCP rather than 0 to socket(), so that the Linux
      seccomp2 sandbox doesn't fail. Fixes bug 14989; bugfix
      on 0.2.6.3-alpha.
    - Allow AF_UNIX hidden services to be used with the seccomp2
      sandbox. Fixes bug 15003; bugfix on 0.2.6.3-alpha.
    - Upon receiving sighup with the seccomp2 sandbox enabled, do not
      crash during attempts to call wait4. Fixes bug 15088; bugfix on
      0.2.5.1-alpha. Patch from "sanic".

  o Minor features (controller):
    - Messages about problems in the bootstrap process now include
      information about the server we were trying to connect to when we
      noticed the problem. Closes ticket 15006.

  o Minor features (geoip):
    - Update geoip to the March 3 2015 Maxmind GeoLite2 Country database.
    - Update geoip6 to the March 3 2015 Maxmind GeoLite2
      Country database.

  o Minor features (logs):
    - Quiet some log messages in the heartbeat and at startup. Closes
      ticket 14950.

  o Minor bugfixes (certificate handling):
    - If an authority operator accidentally makes a signing certificate
      with a future publication time, do not discard its real signing
      certificates. Fixes bug 11457; bugfix on 0.2.0.3-alpha.
    - Remove any old authority certificates that have been superseded
      for at least two days. Previously, we would keep superseded
      certificates until they expired, if they were published close in
      time to the certificate that superseded them. Fixes bug 11454;
      bugfix on 0.2.1.8-alpha.

  o Minor bugfixes (compilation):
    - Fix a compilation warning on s390. Fixes bug 14988; bugfix
      on 0.2.5.2-alpha.
    - Fix a compilation warning on FreeBSD. Fixes bug 15151; bugfix
      on 0.2.6.2-alpha.

  o Minor bugfixes (testing):
    - Fix endianness issues in unit test for resolve_my_address() to
      have it pass on big endian systems. Fixes bug 14980; bugfix on
      Tor 0.2.6.3-alpha.
    - Avoid a side-effect in a tor_assert() in the unit tests. Fixes bug
      15188; bugfix on 0.1.2.3-alpha. Patch from Tom van der Woerdt.
    - When running the new 'make test-stem' target, use the configured
      python binary. Fixes bug 15037; bugfix on 0.2.6.3-alpha. Patch
      from "cypherpunks".
    - When running the zero-length-keys tests, do not use the default
      torrc file. Fixes bug 15033; bugfix on 0.2.6.3-alpha. Reported
      by "reezer".

  o Directory authority IP change:
    - The directory authority Faravahar has a new IP address. This
      closes ticket 14487.

  o Removed code:
    - Remove some lingering dead code that once supported mempools.
      Mempools were disabled by default in 0.2.5, and removed entirely
      in 0.2.6.3-alpha. Closes more of ticket 14848; patch
      by "cypherpunks".


Changes in version 0.2.6.3-alpha - 2015-02-19
  Tor 0.2.6.3-alpha is the third (and hopefully final) alpha release in
  the 0.2.6.x series. It introduces support for more kinds of sockets,
  makes it harder to accidentally run an exit, improves our
  multithreading backend, incorporates several fixes for the
  AutomapHostsOnResolve option, and fixes numerous other bugs besides.

  If no major regressions or security holes are found in this version,
  the next version will be a release candidate.

  o Deprecated versions:
    - Tor relays older than 0.2.4.18-rc are no longer allowed to
      advertise themselves on the network. Closes ticket 13555.

  o Major features (security, unix domain sockets):
    - Allow SocksPort to be an AF_UNIX Unix Domain Socket. Now high risk
      applications can reach Tor without having to create AF_INET or
      AF_INET6 sockets, meaning they can completely disable their
      ability to make non-Tor network connections. To create a socket of
      this type, use "SocksPort unix:/path/to/socket". Implements
      ticket 12585.
    - Support mapping hidden service virtual ports to AF_UNIX sockets.
      The syntax is "HiddenServicePort 80 unix:/path/to/socket".
      Implements ticket 11485.

  o Major features (changed defaults):
    - Prevent relay operators from unintentionally running exits: When a
      relay is configured as an exit node, we now warn the user unless
      the "ExitRelay" option is set to 1. We warn even more loudly if
      the relay is configured with the default exit policy, since this
      can indicate accidental misconfiguration. Setting "ExitRelay 0"
      stops Tor from running as an exit relay. Closes ticket 10067.

  o Major features (directory system):
    - When downloading server- or microdescriptors from a directory
      server, we no longer launch multiple simultaneous requests to the
      same server. This reduces load on the directory servers,
      especially when directory guards are in use. Closes ticket 9969.
    - When downloading server- or microdescriptors over a tunneled
      connection, do not limit the length of our requests to what the
      Squid proxy is willing to handle. Part of ticket 9969.
    - Authorities can now vote on the correct digests and latest
      versions for different software packages. This allows packages
      that include Tor to use the Tor authority system as a way to get
      notified of updates and their correct digests. Implements proposal
      227. Closes ticket 10395.

  o Major features (guards):
    - Introduce the Guardfraction feature to improves load balancing on
      guard nodes. Specifically, it aims to reduce the traffic gap that
      guard nodes experience when they first get the Guard flag. This is
      a required step if we want to increase the guard lifetime to 9
      months or greater.  Closes ticket 9321.

  o Major features (performance):
    - Make the CPU worker implementation more efficient by avoiding the
      kernel and lengthening pipelines. The original implementation used
      sockets to transfer data from the main thread to the workers, and
      didn't allow any thread to be assigned more than a single piece of
      work at once. The new implementation avoids communications
      overhead by making requests in shared memory, avoiding kernel IO
      where possible, and keeping more requests in flight at once.
      Implements ticket 9682.

  o Major features (relay):
    - Raise the minimum acceptable configured bandwidth rate for bridges
      to 50 KiB/sec and for relays to 75 KiB/sec. (The old values were
      20 KiB/sec.) Closes ticket 13822.

  o Major bugfixes (exit node stability):
    - Fix an assertion failure that could occur under high DNS load.
      Fixes bug 14129; bugfix on Tor 0.0.7rc1. Found by "jowr";
      diagnosed and fixed by "cypherpunks".

  o Major bugfixes (mixed relay-client operation):
    - When running as a relay and client at the same time (not
      recommended), if we decide not to use a new guard because we want
      to retry older guards, only close the locally-originating circuits
      passing through that guard. Previously we would close all the
      circuits through that guard. Fixes bug 9819; bugfix on
      0.2.1.1-alpha. Reported by "skruffy".

  o Minor features (build):
    - New --disable-system-torrc compile-time option to prevent Tor from
      looking for the system-wide torrc or torrc-defaults files.
      Resolves ticket 13037.

  o Minor features (controller):
    - Include SOCKS_USERNAME and SOCKS_PASSWORD values in controller
      events so controllers can observe circuit isolation inputs. Closes
      ticket 8405.
    - ControlPort now supports the unix:/path/to/socket syntax as an
      alternative to the ControlSocket option, for consistency with
      SocksPort and HiddenServicePort. Closes ticket 14451.
    - New "GETINFO bw-event-cache" to get information about recent
      bandwidth events. Closes ticket 14128. Useful for controllers to
      get recent bandwidth history after the fix for ticket 13988.

  o Minor features (Denial of service resistance):
    - Count the total number of bytes used storing hidden service
      descriptors against the value of MaxMemInQueues. If we're low on
      memory, and more than 20% of our memory is used holding hidden
      service descriptors, free them until no more than 10% of our
      memory holds hidden service descriptors. Free the least recently
      fetched descriptors first. Resolves ticket 13806.
    - When we have recently been under memory pressure (over 3/4 of
      MaxMemInQueues is allocated), then allocate smaller zlib objects
      for small requests. Closes ticket 11791.

  o Minor features (geoip):
    - Update geoip and geoip6 files to the January 7 2015 Maxmind
      GeoLite2 Country database.

  o Minor features (guard nodes):
    - Reduce the time delay before saving guard status to disk from 10
      minutes to 30 seconds (or from one hour to 10 minutes if
      AvoidDiskWrites is set). Closes ticket 12485.

  o Minor features (hidden service):
    - Make Sybil attacks against hidden services harder by changing the
      minimum time required to get the HSDir flag from 25 hours up to 96
      hours. Addresses ticket 14149.
    - New option "HiddenServiceAllowUnknownPorts" to allow hidden
      services to disable the anti-scanning feature introduced in
      0.2.6.2-alpha. With this option not set, a connection to an
      unlisted port closes the circuit. With this option set, only a
      RELAY_DONE cell is sent. Closes ticket 14084.

  o Minor features (interface):
    - Implement "-f -" command-line option to read torrc configuration
      from standard input, if you don't want to store the torrc file in
      the file system. Implements feature 13865.

  o Minor features (logging):
    - Add a count of unique clients to the bridge heartbeat message.
      Resolves ticket 6852.
    - Suppress "router info incompatible with extra info" message when
      reading extrainfo documents from cache. (This message got loud
      around when we closed bug 9812 in 0.2.6.2-alpha.) Closes
      ticket 13762.
    - Elevate hidden service authorized-client message from DEBUG to
      INFO. Closes ticket 14015.

  o Minor features (stability):
    - Add assertions in our hash-table iteration code to check for
      corrupted values that could cause infinite loops. Closes
      ticket 11737.

  o Minor features (systemd):
    - Various improvements and modernizations in systemd hardening
      support. Closes ticket 13805. Patch from Craig Andrews.

  o Minor features (testing networks):
    - Drop the minimum RendPostPeriod on a testing network to 5 seconds,
      and the default on a testing network to 2 minutes. Drop the
      MIN_REND_INITIAL_POST_DELAY on a testing network to 5 seconds, but
      keep the default on a testing network at 30 seconds. This reduces
      HS bootstrap time to around 25 seconds. Also, change the default
      time in test-network.sh to match. Closes ticket 13401. Patch
      by "teor".
    - Create TestingDirAuthVoteHSDir to correspond to
      TestingDirAuthVoteExit/Guard. Ensures that authorities vote the
      HSDir flag for the listed relays regardless of uptime or ORPort
      connectivity. Respects the value of VoteOnHidServDirectoriesV2.
      Partial implementation for ticket 14067. Patch by "teor".

  o Minor features (tor2web mode):
    - Introduce the config option Tor2webRendezvousPoints, which allows
      clients in Tor2webMode to select a specific Rendezvous Point to be
      used in HS circuits. This might allow better performance for
      Tor2Web nodes. Implements ticket 12844.

  o Minor bugfixes (client DNS):
    - Report the correct cached DNS expiration times on SOCKS port or in
      DNS replies. Previously, we would report everything as "never
      expires." Fixes bug 14193; bugfix on 0.2.3.17-beta.
    - Avoid a small memory leak when we find a cached answer for a
      reverse DNS lookup in a client-side DNS cache. (Remember, client-
      side DNS caching is off by default, and is not recommended.) Fixes
      bug 14259; bugfix on 0.2.0.1-alpha.

  o Minor bugfixes (client, automapping):
    - Avoid crashing on torrc lines for VirtualAddrNetworkIPv[4|6] when
      no value follows the option. Fixes bug 14142; bugfix on
      0.2.4.7-alpha. Patch by "teor".
    - Fix a memory leak when using AutomapHostsOnResolve. Fixes bug
      14195; bugfix on 0.1.0.1-rc.
    - Prevent changes to other options from removing the wildcard value
      "." from "AutomapHostsSuffixes". Fixes bug 12509; bugfix
      on 0.2.0.1-alpha.
    - Allow MapAddress and AutomapHostsOnResolve to work together when
      an address is mapped into another address type (like .onion) that
      must be automapped at resolve time. Fixes bug 7555; bugfix
      on 0.2.0.1-alpha.

  o Minor bugfixes (client, bridges):
    - When we are using bridges and we had a network connectivity
      problem, only retry connecting to our currently configured
      bridges, not all bridges we know about and remember using. Fixes
      bug 14216; bugfix on 0.2.2.17-alpha.

  o Minor bugfixes (client, IPv6):
    - Reject socks requests to literal IPv6 addresses when IPv6Traffic
      flag is not set; and not because the NoIPv4Traffic flag was set.
      Previously we'd looked at the NoIPv4Traffic flag for both types of
      literal addresses. Fixes bug 14280; bugfix on 0.2.4.7-alpha.

  o Minor bugfixes (compilation):
    - The address of an array in the middle of a structure will always
      be non-NULL. clang recognises this and complains. Disable the
      tautologous and redundant check to silence this warning. Fixes bug
      14001; bugfix on 0.2.1.2-alpha.
    - Avoid warnings when building with systemd 209 or later. Fixes bug
      14072; bugfix on 0.2.6.2-alpha. Patch from "h.venev".
    - Compile correctly with (unreleased) OpenSSL 1.1.0 headers.
      Addresses ticket 14188.
    - Build without warnings with the stock OpenSSL srtp.h header, which
      has a duplicate declaration of SSL_get_selected_srtp_profile().
      Fixes bug 14220; this is OpenSSL's bug, not ours.
    - Do not compile any code related to Tor2Web mode when Tor2Web mode
      is not enabled at compile time. Previously, this code was included
      in a disabled state. See discussion on ticket 12844.
    - Remove the --disable-threads configure option again. It was
      accidentally partially reintroduced in 29ac883606d6d. Fixes bug
      14819; bugfix on 0.2.6.2-alpha.

  o Minor bugfixes (controller):
    - Report "down" in response to the "GETINFO entry-guards" command
      when relays are down with an unreachable_since value. Previously,
      we would report "up". Fixes bug 14184; bugfix on 0.1.2.2-alpha.
    - Avoid crashing on a malformed EXTENDCIRCUIT command. Fixes bug
      14116; bugfix on 0.2.2.9-alpha.
    - Add a code for the END_CIRC_REASON_IP_NOW_REDUNDANT circuit close
      reason. Fixes bug 14207; bugfix on 0.2.6.2-alpha.

  o Minor bugfixes (directory authority):
    - Allow directory authorities to fetch more data from one another if
      they find themselves missing lots of votes. Previously, they had
      been bumping against the 10 MB queued data limit. Fixes bug 14261;
      bugfix on 0.1.2.5-alpha.
    - Do not attempt to download extrainfo documents which we will be
      unable to validate with a matching server descriptor. Fixes bug
      13762; bugfix on 0.2.0.1-alpha.
    - Fix a bug that was truncating AUTHDIR_NEWDESC events sent to the
      control port. Fixes bug 14953; bugfix on 0.2.0.1-alpha.
    - Enlarge the buffer to read bwauth generated files to avoid an
      issue when parsing the file in dirserv_read_measured_bandwidths().
      Fixes bug 14125; bugfix on 0.2.2.1-alpha.

  o Minor bugfixes (file handling):
    - Stop failing when key files are zero-length. Instead, generate new
      keys, and overwrite the empty key files. Fixes bug 13111; bugfix
      on all versions of Tor. Patch by "teor".
    - Stop generating a fresh .old RSA onion key file when the .old file
      is missing. Fixes part of 13111; bugfix on 0.0.6rc1.
    - Avoid overwriting .old key files with empty key files.
    - Skip loading zero-length extrainfo store, router store, stats,
      state, and key files.
    - Avoid crashing when trying to reload a torrc specified as a
      relative path with RunAsDaemon turned on. Fixes bug 13397; bugfix
      on 0.2.3.11-alpha.

  o Minor bugfixes (hidden services):
    - Close the introduction circuit when we have no more usable intro
      points, instead of waiting for it to time out. This also ensures
      that no follow-up HS descriptor fetch is triggered when the
      circuit eventually times out. Fixes bug 14224; bugfix on 0.0.6.
    - When fetching a hidden service descriptor for a down service that
      was recently up, do not keep refetching until we try the same
      replica twice in a row. Fixes bug 14219; bugfix on 0.2.0.10-alpha.
    - Successfully launch Tor with a nonexistent hidden service
      directory. Our fix for bug 13942 didn't catch this case. Fixes bug
      14106; bugfix on 0.2.6.2-alpha.

  o Minor bugfixes (logging):
    - Avoid crashing when there are more log domains than entries in
      domain_list. Bugfix on 0.2.3.1-alpha.
    - Add a string representation for LD_SCHED. Fixes bug 14740; bugfix
      on 0.2.6.1-alpha.
    - Don't log messages to stdout twice when starting up. Fixes bug
      13993; bugfix on 0.2.6.1-alpha.

  o Minor bugfixes (parsing):
    - Stop accepting milliseconds (or other junk) at the end of
      descriptor publication times. Fixes bug 9286; bugfix on 0.0.2pre25.
    - Support two-number and three-number version numbers correctly, in
      case we change the Tor versioning system in the future. Fixes bug
      13661; bugfix on 0.0.8pre1.

  o Minor bugfixes (path counting):
    - When deciding whether the consensus lists any exit nodes, count
      the number listed in the consensus, not the number we have
      descriptors for. Fixes part of bug 14918; bugfix on 0.2.6.2-alpha.
    - When deciding whether we have any exit nodes, only examine
      ExitNodes when the ExitNodes option is actually set. Fixes part of
      bug 14918; bugfix on 0.2.6.2-alpha.
    - Get rid of redundant and possibly scary warnings that we are
      missing directory information while we bootstrap. Fixes part of
      bug 14918; bugfix on 0.2.6.2-alpha.

  o Minor bugfixes (portability):
    - Fix the ioctl()-based network interface lookup code so that it
      will work on systems that have variable-length struct ifreq, for
      example Mac OS X.
    - Fix scheduler compilation on targets where char is unsigned. Fixes
      bug 14764; bugfix on 0.2.6.2-alpha. Reported by Christian Kujau.

  o Minor bugfixes (sandbox):
    - Allow glibc fatal errors to be sent to stderr before Tor exits.
      Previously, glibc would try to write them to /dev/tty, and the
      sandbox would trap the call and make Tor exit prematurely. Fixes
      bug 14759; bugfix on 0.2.5.1-alpha.

  o Minor bugfixes (shutdown):
    - When shutting down, always call event_del() on lingering read or
      write events before freeing them. Otherwise, we risk double-frees
      or read-after-frees in event_base_free(). Fixes bug 12985; bugfix
      on 0.1.0.2-rc.

  o Minor bugfixes (small memory leaks):
    - Avoid leaking memory when using IPv6 virtual address mappings.
      Fixes bug 14123; bugfix on 0.2.4.7-alpha. Patch by Tom van
      der Woerdt.

  o Minor bugfixes (statistics):
    - Increase period over which bandwidth observations are aggregated
      from 15 minutes to 4 hours. Fixes bug 13988; bugfix on 0.0.8pre1.

  o Minor bugfixes (systemd support):
    - Fix detection and operation of systemd watchdog. Fixes part of bug
      14141; bugfix on 0.2.6.2-alpha. Patch from Tomasz Torcz.
    - Run correctly under systemd with the RunAsDaemon option set. Fixes
      part of bug 14141; bugfix on 0.2.5.7-rc. Patch from Tomasz Torcz.
    - Inform the systemd supervisor about more changes in the Tor
      process status. Implements part of ticket 14141. Patch from
      Tomasz Torcz.
    - Cause the "--disable-systemd" option to actually disable systemd
      support. Fixes bug 14350; bugfix on 0.2.6.2-alpha. Patch
      from "blueness".

  o Minor bugfixes (TLS):
    - Check more thoroughly throughout the TLS code for possible
      unlogged TLS errors. Possible diagnostic or fix for bug 13319.

  o Minor bugfixes (transparent proxy):
    - Use getsockname, not getsockopt, to retrieve the address for a
      TPROXY-redirected connection. Fixes bug 13796; bugfix
      on 0.2.5.2-alpha.

  o Code simplification and refactoring:
    - Move fields related to isolating and configuring client ports into
      a shared structure. Previously, they were duplicated across
      port_cfg_t, listener_connection_t, and edge_connection_t. Failure
      to copy them correctly had been the cause of at least one bug in
      the past. Closes ticket 8546.
    - Refactor the get_interface_addresses_raw() doom-function into
      multiple smaller and simpler subfunctions. Cover the resulting
      subfunctions with unit-tests. Fixes a significant portion of
      issue 12376.
    - Remove workaround in dirserv_thinks_router_is_hs_dir() that was
      only for version <= 0.2.2.24 which is now deprecated. Closes
      ticket 14202.
    - Remove a test for a long-defunct broken version-one
      directory server.

  o Documentation:
    - Adding section on OpenBSD to our TUNING document. Thanks to mmcc
      for writing the OpenBSD-specific tips. Resolves ticket 13702.
    - Make the tor-resolve documentation match its help string and its
      options. Resolves part of ticket 14325.
    - Log a more useful error message from tor-resolve when failing to
      look up a hidden service address. Resolves part of ticket 14325.

  o Downgraded warnings:
    - Don't warn when we've attempted to contact a relay using the wrong
      ntor onion key. Closes ticket 9635.

  o Removed features:
    - To avoid confusion with the "ExitRelay" option, "ExitNode" is no
      longer silently accepted as an alias for "ExitNodes".
    - The --enable-mempool and --enable-buf-freelists options, which
      were originally created to work around bad malloc implementations,
      no longer exist. They were off-by-default in 0.2.5. Closes
      ticket 14848.

  o Testing:
    - Make the checkdir/perms test complete successfully even if the
      global umask is not 022. Fixes bug 14215; bugfix on 0.2.6.2-alpha.
    - Test that tor does not fail when key files are zero-length. Check
      that tor generates new keys, and overwrites the empty key files.
    - Test that tor generates new keys when keys are missing
      (existing behavior).
    - Test that tor does not overwrite key files that already contain
      data (existing behavior). Tests bug 13111. Patch by "teor".
    - New "make test-stem" target to run stem integration tests.
      Requires that the "STEM_SOURCE_DIR" environment variable be set.
      Closes ticket 14107.
    - Make the test_cmdline_args.py script work correctly on Windows.
      Patch from Gisle Vanem.
    - Move the slower unit tests into a new "./src/test/test-slow"
      binary that can be run independently of the other tests. Closes
      ticket 13243.
    - Avoid undefined behavior when sampling huge values from the
      Laplace distribution. This made unittests fail on Raspberry Pi.
      Bug found by Device. Fixes bug 14090; bugfix on 0.2.6.2-alpha.


Changes in version 0.2.6.2-alpha - 2014-12-31
  Tor 0.2.6.2-alpha is the second alpha release in the 0.2.6.x series.
  It introduces a major new backend for deciding when to send cells on
  channels, which should lead down the road to big performance
  increases. It contains security and statistics features for better
  work on hidden services, and numerous bugfixes.

  This release contains many new unit tests, along with major
  performance improvements for running testing networks using Chutney.
  Thanks to a series of patches contributed by "teor", testing networks
  should now bootstrap in seconds, rather than minutes.

  o Major features (relay, infrastructure):
    - Complete revision of the code that relays use to decide which cell
      to send next. Formerly, we selected the best circuit to write on
      each channel, but we didn't select among channels in any
      sophisticated way. Now, we choose the best circuits globally from
      among those whose channels are ready to deliver traffic.

      This patch implements a new inter-cmux comparison API, a global
      high/low watermark mechanism and a global scheduler loop for
      transmission prioritization across all channels as well as among
      circuits on one channel. This schedule is currently tuned to
      (tolerantly) avoid making changes in network performance, but it
      should form the basis for major circuit performance increases in
      the future. Code by Andrea; tuning by Rob Jansen; implements
      ticket 9262.

  o Major features (hidden services):
    - Make HS port scanning more difficult by immediately closing the
      circuit when a user attempts to connect to a nonexistent port.
      Closes ticket 13667.
    - Add a HiddenServiceStatistics option that allows Tor relays to
      gather and publish statistics about the overall size and volume of
      hidden service usage. Specifically, when this option is turned on,
      an HSDir will publish an approximate number of hidden services
      that have published descriptors to it the past 24 hours. Also, if
      a relay has acted as a hidden service rendezvous point, it will
      publish the approximate amount of rendezvous cells it has relayed
      the past 24 hours. The statistics themselves are obfuscated so
      that the exact values cannot be derived. For more details see
      proposal 238, "Better hidden service stats from Tor relays". This
      feature is currently disabled by default. Implements feature 13192.

  o Major bugfixes (client, automap):
    - Repair automapping with IPv6 addresses. This automapping should
      have worked previously, but one piece of debugging code that we
      inserted to detect a regression actually caused the regression to
      manifest itself again. Fixes bug 13811 and bug 12831; bugfix on
      0.2.4.7-alpha. Diagnosed and fixed by Francisco Blas
      Izquierdo Riera.

  o Major bugfixes (hidden services):
    - When closing an introduction circuit that was opened in parallel
      with others, don't mark the introduction point as unreachable.
      Previously, the first successful connection to an introduction
      point would make the other introduction points get marked as
      having timed out. Fixes bug 13698; bugfix on 0.0.6rc2.

  o Directory authority changes:
    - Remove turtles as a directory authority.
    - Add longclaw as a new (v3) directory authority. This implements
      ticket 13296. This keeps the directory authority count at 9.

  o Major removed features:
    - Tor clients no longer support connecting to hidden services
      running on Tor 0.2.2.x and earlier; the Support022HiddenServices
      option has been removed. (There shouldn't be any hidden services
      running these versions on the network.) Closes ticket 7803.

  o Minor features (client):
    - Validate hostnames in SOCKS5 requests more strictly. If SafeSocks
      is enabled, reject requests with IP addresses as hostnames.
      Resolves ticket 13315.

  o Minor features (controller):
    - Add a "SIGNAL HEARTBEAT" controller command that tells Tor to
      write an unscheduled heartbeat message to the log. Implements
      feature 9503.

  o Minor features (geoip):
    - Update geoip and geoip6 to the November 15 2014 Maxmind GeoLite2
      Country database.

  o Minor features (hidden services):
    - When re-enabling the network, don't try to build introduction
      circuits until we have successfully built a circuit. This makes
      hidden services come up faster when the network is re-enabled.
      Patch from "akwizgran". Closes ticket 13447.
    - When we fail to retrieve a hidden service descriptor, send the
      controller an "HS_DESC FAILED" controller event. Implements
      feature 13212.
    - New HiddenServiceDirGroupReadable option to cause hidden service
      directories and hostname files to be created group-readable. Patch
      from "anon", David Stainton, and "meejah". Closes ticket 11291.

  o Minor features (systemd):
    - Where supported, when running with systemd, report successful
      startup to systemd. Part of ticket 11016. Patch by Michael Scherer.
    - When running with systemd, support systemd watchdog messages. Part
      of ticket 11016. Patch by Michael Scherer.

  o Minor features (transparent proxy):
    - Update the transparent proxy option checks to allow for both ipfw
      and pf on OS X. Closes ticket 14002.
    - Use the correct option when using IPv6 with transparent proxy
      support on Linux. Resolves 13808. Patch by Francisco Blas
      Izquierdo Riera.

  o Minor bugfixes (preventative security, C safety):
    - When reading a hexadecimal, base-32, or base-64 encoded value from
      a string, always overwrite the whole output buffer. This prevents
      some bugs where we would look at (but fortunately, not reveal)
      uninitialized memory on the stack. Fixes bug 14013; bugfix on all
      versions of Tor.
    - Clear all memory targeted by tor_addr_{to,from}_sockaddr(), not
      just the part that's used. This makes it harder for data leak bugs
      to occur in the event of other programming failures. Resolves
      ticket 14041.

  o Minor bugfixes (client, microdescriptors):
    - Use a full 256 bits of the SHA256 digest of a microdescriptor when
      computing which microdescriptors to download. This keeps us from
      erroneous download behavior if two microdescriptor digests ever
      have the same first 160 bits. Fixes part of bug 13399; bugfix
      on 0.2.3.1-alpha.
    - Reset a router's status if its microdescriptor digest changes,
      even if the first 160 bits remain the same. Fixes part of bug
      13399; bugfix on 0.2.3.1-alpha.

  o Minor bugfixes (compilation):
    - Silence clang warnings under --enable-expensive-hardening,
      including implicit truncation of 64 bit values to 32 bit, const
      char assignment to self, tautological compare, and additional
      parentheses around equality tests. Fixes bug 13577; bugfix
      on 0.2.5.4-alpha.
    - Fix a clang warning about checking whether an address in the
      middle of a structure is NULL. Fixes bug 14001; bugfix
      on 0.2.1.2-alpha.

  o Minor bugfixes (hidden services):
    - Correctly send a controller event when we find that a rendezvous
      circuit has finished. Fixes bug 13936; bugfix on 0.1.1.5-alpha.
    - Pre-check directory permissions for new hidden-services to avoid
      at least one case of "Bug: Acting on config options left us in a
      broken state. Dying." Fixes bug 13942; bugfix on 0.0.6pre1.
    - When adding a new hidden service (for example, via SETCONF), Tor
      no longer congratulates the user for running a relay. Fixes bug
      13941; bugfix on 0.2.6.1-alpha.
    - When fetching hidden service descriptors, we now check not only
      for whether we got the hidden service we had in mind, but also
      whether we got the particular descriptors we wanted. This prevents
      a class of inefficient but annoying DoS attacks by hidden service
      directories. Fixes bug 13214; bugfix on 0.2.1.6-alpha. Reported
      by "special".

  o Minor bugfixes (Linux seccomp2 sandbox):
    - Make transparent proxy support work along with the seccomp2
      sandbox. Fixes part of bug 13808; bugfix on 0.2.5.1-alpha. Patch
      by Francisco Blas Izquierdo Riera.
    - Fix a memory leak in tor-resolve when running with the sandbox
      enabled. Fixes bug 14050; bugfix on 0.2.5.9-rc.

  o Minor bugfixes (logging):
    - Downgrade warnings about RSA signature failures to info log level.
      Emit a warning when an extra info document is found incompatible
      with a corresponding router descriptor. Fixes bug 9812; bugfix
      on 0.0.6rc3.
    - Make connection_ap_handshake_attach_circuit() log the circuit ID
      correctly. Fixes bug 13701; bugfix on 0.0.6.

  o Minor bugfixes (misc):
    - Stop allowing invalid address patterns like "*/24" that contain
      both a wildcard address and a bit prefix length. This affects all
      our address-range parsing code. Fixes bug 7484; bugfix
      on 0.0.2pre14.

  o Minor bugfixes (testing networks, fast startup):
    - Allow Tor to build circuits using a consensus with no exits. If
      the consensus has no exits (typical of a bootstrapping test
      network), allow Tor to build circuits once enough descriptors have
      been downloaded. This assists in bootstrapping a testing Tor
      network. Fixes bug 13718; bugfix on 0.2.4.10-alpha. Patch
      by "teor".
    - When V3AuthVotingInterval is low, give a lower If-Modified-Since
      header to directory servers. This allows us to obtain consensuses
      promptly when the consensus interval is very short. This assists
      in bootstrapping a testing Tor network. Fixes parts of bugs 13718
      and 13963; bugfix on 0.2.0.3-alpha. Patch by "teor".
    - Stop assuming that private addresses are local when checking
      reachability in a TestingTorNetwork. Instead, when testing, assume
      all OR connections are remote. (This is necessary due to many test
      scenarios running all relays on localhost.) This assists in
      bootstrapping a testing Tor network. Fixes bug 13924; bugfix on
      0.1.0.1-rc. Patch by "teor".
    - Avoid building exit circuits from a consensus with no exits. Now
      thanks to our fix for 13718, we accept a no-exit network as not
      wholly lost, but we need to remember not to try to build exit
      circuits on it. Closes ticket 13814; patch by "teor".
    - Stop requiring exits to have non-zero bandwithcapacity in a
      TestingTorNetwork. Instead, when TestingMinExitFlagThreshold is 0,
      ignore exit bandwidthcapacity. This assists in bootstrapping a
      testing Tor network. Fixes parts of bugs 13718 and 13839; bugfix
      on 0.2.0.3-alpha. Patch by "teor".
    - Add "internal" to some bootstrap statuses when no exits are
      available. If the consensus does not contain Exits, Tor will only
      build internal circuits. In this case, relevant statuses will
      contain the word "internal" as indicated in the Tor control-
       spec.txt. When bootstrap completes, Tor will be ready to build
      internal circuits. If a future consensus contains Exits, exit
      circuits may become available. Fixes part of bug 13718; bugfix on
      0.2.4.10-alpha. Patch by "teor".
    - Decrease minimum consensus interval to 10 seconds when
      TestingTorNetwork is set, or 5 seconds for the first consensus.
      Fix assumptions throughout the code that assume larger intervals.
      Fixes bugs 13718 and 13823; bugfix on 0.2.0.3-alpha. Patch
      by "teor".
    - Avoid excluding guards from path building in minimal test
      networks, when we're in a test network and excluding guards would
      exclude all relays. This typically occurs in incredibly small tor
      networks, and those using "TestingAuthVoteGuard *". Fixes part of
      bug 13718; bugfix on 0.1.1.11-alpha. Patch by "teor".

  o Code simplification and refactoring:
    - Stop using can_complete_circuits as a global variable; access it
      with a function instead.
    - Avoid using operators directly as macro arguments: this lets us
      apply coccinelle transformations to our codebase more directly.
      Closes ticket 13172.
    - Combine the functions used to parse ClientTransportPlugin and
      ServerTransportPlugin into a single function. Closes ticket 6456.
    - Add inline functions and convenience macros for inspecting channel
      state. Refactor the code to use convenience macros instead of
      checking channel state directly. Fixes issue 7356.
    - Document all members of was_router_added_t and rename
      ROUTER_WAS_NOT_NEW to ROUTER_IS_ALREADY_KNOWN to make it less
      confusable with ROUTER_WAS_TOO_OLD. Fixes issue 13644.
    - In connection_exit_begin_conn(), use END_CIRC_REASON_TORPROTOCOL
      constant instead of hardcoded value. Fixes issue 13840.
    - Refactor our generic strmap and digestmap types into a single
      implementation, so that we can add a new digest256map
      type trivially.

  o Documentation:
    - Document the bridge-authority-only 'networkstatus-bridges' file.
      Closes ticket 13713; patch from "tom".
    - Fix typo in PredictedPortsRelevanceTime option description in
      manpage. Resolves issue 13707.
    - Stop suggesting that users specify relays by nickname: it isn't a
      good idea. Also, properly cross-reference how to specify relays in
      all parts of manual documenting options that take a list of
      relays. Closes ticket 13381.
    - Clarify the HiddenServiceDir option description in manpage to make
      it clear that relative paths are taken with respect to the current
      working directory. Also clarify that this behavior is not
      guaranteed to remain indefinitely. Fixes issue 13913.

  o Testing:
    - New tests for many parts of channel, relay, and circuitmux
      functionality. Code by Andrea; part of 9262.
    - New tests for parse_transport_line(). Part of ticket 6456.
    - In the unit tests, use chgrp() to change the group of the unit
      test temporary directory to the current user, so that the sticky
      bit doesn't interfere with tests that check directory groups.
      Closes 13678.
    - Add unit tests for resolve_my_addr(). Part of ticket 12376; patch
      by 'rl1987'.


Changes in version 0.2.6.1-alpha - 2014-10-30
  Tor 0.2.6.1-alpha is the first release in the Tor 0.2.6.x series. It
  includes numerous code cleanups and new tests, and fixes a large
  number of annoying bugs. Out-of-memory conditions are handled better
  than in 0.2.5, pluggable transports have improved proxy support, and
  clients now use optimistic data for contacting hidden services. Also,
  we are now more robust to changes in what we consider a parseable
  directory object, so that tightening restrictions does not have a risk
  of introducing infinite download loops.

  This is the first alpha release in a new series, so expect there to be
  bugs. Users who would rather test out a more stable branch should stay
  with 0.2.5.x for now.

  o New compiler and system requirements:
    - Tor 0.2.6.x requires that your compiler support more of the C99
      language standard than before. The 'configure' script now detects
      whether your compiler supports C99 mid-block declarations and
      designated initializers. If it does not, Tor will not compile.

      We may revisit this requirement if it turns out that a significant
      number of people need to build Tor with compilers that don't
      bother implementing a 15-year-old standard. Closes ticket 13233.
    - Tor no longer supports systems without threading support. When we
      began working on Tor, there were several systems that didn't have
      threads, or where the thread support wasn't able to run the
      threads of a single process on multiple CPUs. That no longer
      holds: every system where Tor needs to run well now has threading
      support. Resolves ticket 12439.

  o Removed platform support:
    - We no longer include special code to build on Windows CE; as far
      as we know, nobody has used Tor on Windows CE in a very long time.
      Closes ticket 11446.

  o Major features (bridges):
    - Expose the outgoing upstream HTTP/SOCKS proxy to pluggable
      transports if they are configured via the "TOR_PT_PROXY"
      environment variable. Implements proposal 232. Resolves
      ticket 8402.

  o Major features (client performance, hidden services):
    - Allow clients to use optimistic data when connecting to a hidden
      service, which should remove a round-trip from hidden service
      initialization. See proposal 181 for details. Implements
      ticket 13211.

  o Major features (directory system):
    - Upon receiving an unparseable directory object, if its digest
      matches what we expected, then don't try to download it again.
      Previously, when we got a descriptor we didn't like, we would keep
      trying to download it over and over. Closes ticket 11243.

  o Major features (sample torrc):
    - Add a new, infrequently-changed "torrc.minimal". This file is
      similar to torrc.sample, but it will change as infrequently as
      possible, for the benefit of users whose systems prompt them for
      intervention whenever a default configuration file is changed.
      Making this change allows us to update torrc.sample to be a more
      generally useful "sample torrc".

  o Major bugfixes (directory authorities):
    - Do not assign the HSDir flag to relays if they are not Valid, or
      currently hibernating. Fixes 12573; bugfix on 0.2.0.10-alpha.

  o Major bugfixes (directory bandwidth performance):
    - Don't flush the zlib buffer aggressively when compressing
      directory information for clients. This should save about 7% of
      the bandwidth currently used for compressed descriptors and
      microdescriptors. Fixes bug 11787; bugfix on 0.1.1.23.

  o Minor features (security, memory wiping):
    - Ensure we securely wipe keys from memory after
      crypto_digest_get_digest and init_curve25519_keypair_from_file
      have finished using them. Resolves ticket 13477.

  o Minor features (security, out-of-memory handling):
    - When handling an out-of-memory condition, allocate less memory for
      temporary data structures. Fixes issue 10115.
    - When handling an out-of-memory condition, consider more types of
      buffers, including those on directory connections, and zlib
      buffers. Resolves ticket 11792.

  o Minor features:
    - When identity keypair is generated for first time, log a
      congratulatory message that links to the new relay lifecycle
      document. Implements feature 10427.

  o Minor features (client):
    - Clients are now willing to send optimistic data (before they
      receive a 'connected' cell) to relays of any version. (Relays
      without support for optimistic data are no longer supported on the
      Tor network.) Resolves ticket 13153.

  o Minor features (directory authorities):
    - Don't list relays with a bandwidth estimate of 0 in the consensus.
      Implements a feature proposed during discussion of bug 13000.
    - In tor-gencert, report an error if the user provides the same
      argument more than once.
    - If a directory authority can't find a best consensus method in the
      votes that it holds, it now falls back to its favorite consensus
      method. Previously, it fell back to method 1. Neither of these is
      likely to get enough signatures, but "fall back to favorite"
      doesn't require us to maintain support an obsolete consensus
      method. Implements part of proposal 215.

  o Minor features (logging):
    - On Unix-like systems, you can now use named pipes as the target of
      the Log option, and other options that try to append to files.
      Closes ticket 12061. Patch from "carlo von lynX".
    - When opening a log file at startup, send it every log message that
      we generated between startup and opening it. Previously, log
      messages that were generated before opening the log file were only
      logged to stdout. Closes ticket 6938.
    - Add a TruncateLogFile option to overwrite logs instead of
      appending to them. Closes ticket 5583.

  o Minor features (portability, Solaris):
    - Threads are no longer disabled by default on Solaris; we believe
      that the versions of Solaris with broken threading support are all
      obsolete by now. Resolves ticket 9495.

  o Minor features (relay):
    - Re-check our address after we detect a changed IP address from
      getsockname(). This ensures that the controller command "GETINFO
      address" will report the correct value. Resolves ticket 11582.
      Patch from "ra".
    - A new AccountingRule option lets Relays set whether they'd like
      AccountingMax to be applied separately to inbound and outbound
      traffic, or applied to the sum of inbound and outbound traffic.
      Resolves ticket 961. Patch by "chobe".

  o Minor features (testing networks):
    - Add the TestingDirAuthVoteExit option, which lists nodes to assign
      the "Exit" flag regardless of their uptime, bandwidth, or exit
      policy. TestingTorNetwork must be set for this option to have any
      effect. Previously, authorities would take up to 35 minutes to
      give nodes the Exit flag in a test network. Partially implements
      ticket 13161.

  o Minor features (validation):
    - Check all date/time values passed to tor_timegm and
      parse_rfc1123_time for validity, taking leap years into account.
      Improves HTTP header validation. Implemented with bug 13476.
    - In correct_tm(), limit the range of values returned by system
      localtime(_r) and gmtime(_r) to be between the years 1 and 8099.
      This means we don't have to deal with negative or too large dates,
      even if a clock is wrong. Otherwise we might fail to read a file
      written by us which includes such a date. Fixes bug 13476.

  o Minor bugfixes (bridge clients):
    - When configured to use a bridge without an identity digest (not
      recommended), avoid launching an extra channel to it when
      bootstrapping. Fixes bug 7733; bugfix on 0.2.4.4-alpha.

  o Minor bugfixes (bridges):
    - When DisableNetwork is set, do not launch pluggable transport
      plugins, and if any are running, terminate them. Fixes bug 13213;
      bugfix on 0.2.3.6-alpha.

  o Minor bugfixes (C correctness):
    - Fix several instances of possible integer overflow/underflow/NaN.
      Fixes bug 13104; bugfix on 0.2.3.1-alpha and later. Patches
      from "teor".
    - In circuit_build_times_calculate_timeout() in circuitstats.c,
      avoid dividing by zero in the pareto calculations. This traps
      under clang's "undefined-trap" sanitizer. Fixes bug 13290; bugfix
      on 0.2.2.2-alpha.
    - Fix an integer overflow in format_time_interval(). Fixes bug
      13393; bugfix on 0.2.0.10-alpha.
    - Set the correct day of year value when the system's localtime(_r)
      or gmtime(_r) functions fail to set struct tm. Not externally
      visible. Fixes bug 13476; bugfix on 0.0.2pre14.
    - Avoid unlikely signed integer overflow in tor_timegm on systems
      with 32-bit time_t. Fixes bug 13476; bugfix on 0.0.2pre14.

  o Minor bugfixes (client):
    - Fix smartlist_choose_node_by_bandwidth() so that relays with the
      BadExit flag are not considered worthy candidates. Fixes bug
      13066; bugfix on 0.1.2.3-alpha.
    - Use the consensus schedule for downloading consensuses, and not
      the generic schedule. Fixes bug 11679; bugfix on 0.2.2.6-alpha.
    - Handle unsupported or malformed SOCKS5 requests properly by
      responding with the appropriate error message before closing the
      connection. Fixes bugs 12971 and 13314; bugfix on 0.0.2pre13.

  o Minor bugfixes (client, torrc):
    - Stop modifying the value of our DirReqStatistics torrc option just
      because we're not a bridge or relay. This bug was causing Tor
      Browser users to write "DirReqStatistics 0" in their torrc files
      as if they had chosen to change the config. Fixes bug 4244; bugfix
      on 0.2.3.1-alpha.
    - When GeoIPExcludeUnknown is enabled, do not incorrectly decide
      that our options have changed every time we SIGHUP. Fixes bug
      9801; bugfix on 0.2.4.10-alpha. Patch from "qwerty1".

  o Minor bugfixes (controller):
    - Return an error when the second or later arguments of the
      "setevents" controller command are invalid events. Previously we
      would return success while silently skipping invalid events. Fixes
      bug 13205; bugfix on 0.2.3.2-alpha. Reported by "fpxnns".

  o Minor bugfixes (directory system):
    - Always believe that v3 directory authorities serve extra-info
      documents, whether they advertise "caches-extra-info" or not.
      Fixes part of bug 11683; bugfix on 0.2.0.1-alpha.
    - When running as a v3 directory authority, advertise that you serve
      extra-info documents so that clients who want them can find them
      from you too. Fixes part of bug 11683; bugfix on 0.2.0.1-alpha.
    - Check the BRIDGE_DIRINFO flag bitwise rather than using equality.
      Previously, directories offering BRIDGE_DIRINFO and some other
      flag (i.e. microdescriptors or extrainfo) would be ignored when
      looking for bridges. Partially fixes bug 13163; bugfix
      on 0.2.0.7-alpha.

  o Minor bugfixes (networking):
    - Check for orconns and use connection_or_close_for_error() rather
      than connection_mark_for_close() directly in the getsockopt()
      failure case of connection_handle_write_impl(). Fixes bug 11302;
      bugfix on 0.2.4.4-alpha.

  o Minor bugfixes (relay):
    - When generating our family list, remove spaces from around the
      entries. Fixes bug 12728; bugfix on 0.2.1.7-alpha.
    - If our previous bandwidth estimate was 0 bytes, allow publishing a
      new relay descriptor immediately. Fixes bug 13000; bugfix
      on 0.1.1.6-alpha.

  o Minor bugfixes (testing networks):
    - Fix TestingDirAuthVoteGuard to properly give out Guard flags in a
      testing network. Fixes bug 13064; bugfix on 0.2.5.2-alpha.
    - Stop using the default authorities in networks which provide both
      AlternateDirAuthority and AlternateBridgeAuthority. Partially
      fixes bug 13163; bugfix on 0.2.0.13-alpha.

  o Minor bugfixes (testing):
    - Stop spawn test failures due to a race condition between the
      SIGCHLD handler updating the process status, and the test reading
      it. Fixes bug 13291; bugfix on 0.2.3.3-alpha.

  o Minor bugfixes (testing, Windows):
    - Avoid passing an extra backslash when creating a temporary
      directory for running the unit tests on Windows. Fixes bug 12392;
      bugfix on 0.2.2.25-alpha. Patch from Gisle Vanem.

  o Minor bugfixes (windows):
    - Remove code to special-case handling of NTE_BAD_KEYSET when
      acquiring windows CryptoAPI context. This error can't actually
      occur for the parameters we're providing. Fixes bug 10816; bugfix
      on 0.0.2pre26.

  o Minor bugfixes (zlib):
    - Avoid truncating a zlib stream when trying to finalize it with an
      empty output buffer. Fixes bug 11824; bugfix on 0.1.1.23.

  o Build fixes:
    - Allow our configure script to build correctly with autoconf 2.62
      again. Fixes bug 12693; bugfix on 0.2.5.2-alpha.
    - Improve the error message from ./configure to make it clear that
      when asciidoc has not been found, the user will have to either add
      --disable-asciidoc argument or install asciidoc. Resolves
      ticket 13228.

  o Code simplification and refactoring:
    - Change the entry_is_live() function to take named bitfield
      elements instead of an unnamed list of booleans. Closes
      ticket 12202.
    - Refactor and unit-test entry_is_time_to_retry() in entrynodes.c.
      Resolves ticket 12205.
    - Use calloc and reallocarray functions instead of multiply-
      then-malloc. This makes it less likely for us to fall victim to an
      integer overflow attack when allocating. Resolves ticket 12855.
    - Use the standard macro name SIZE_MAX, instead of our
      own SIZE_T_MAX.
    - Document usage of the NO_DIRINFO and ALL_DIRINFO flags clearly in
      functions which take them as arguments. Replace 0 with NO_DIRINFO
      in a function call for clarity. Seeks to prevent future issues
      like 13163.
    - Avoid 4 null pointer errors under clang static analysis by using
      tor_assert() to prove that the pointers aren't null. Fixes
      bug 13284.
    - Rework the API of policies_parse_exit_policy() to use a bitmask to
      represent parsing options, instead of a confusing mess of
      booleans. Resolves ticket 8197.
    - Introduce a helper function to parse ExitPolicy in
      or_options_t structure.

  o Documentation:
    - Add a doc/TUNING document with tips for handling large numbers of
      TCP connections when running busy Tor relay. Update the warning
      message to point to this file when running out of sockets
      operating system is allowing to use simultaneously. Resolves
      ticket 9708.

  o Removed features:
    - We no longer remind the user about configuration options that have
      been obsolete since 0.2.3.x or earlier. Patch by Adrien Bak.
    - Remove our old, non-weighted bandwidth-based node selection code.
      Previously, we used it as a fallback when we couldn't perform
      weighted bandwidth-based node selection. But that would only
      happen in the cases where we had no consensus, or when we had a
      consensus generated by buggy or ancient directory authorities. In
      either case, it's better to use the more modern, better maintained
      algorithm, with reasonable defaults for the weights. Closes
      ticket 13126.
    - Remove the --disable-curve25519 configure option. Relays and
      clients now are required to support curve25519 and the
      ntor handshake.
    - The old "StrictEntryNodes" and "StrictExitNodes" options, which
      used to be deprecated synonyms for "StrictNodes", are now marked
      obsolete. Resolves ticket 12226.
    - Clients don't understand the BadDirectory flag in the consensus
      anymore, and ignore it.

  o Testing:
    - Refactor the function that chooses guard nodes so that it can more
      easily be tested; write some tests for it.
    - Fix and re-enable the fgets_eagain unit test. Fixes bug 12503;
      bugfix on 0.2.3.1-alpha. Patch from "cypherpunks."
    - Create unit tests for format_time_interval(). With bug 13393.
    - Add unit tests for tor_timegm signed overflow, tor_timegm and
      parse_rfc1123_time validity checks, correct_tm year clamping. Unit
      tests (visible) fixes in bug 13476.
    - Add a "coverage-html" make target to generate HTML-visualized
      coverage results when building with --enable-coverage. (Requires
      lcov.) Patch from Kevin Murray.
    - Enable the backtrace handler (where supported) when running the
      unit tests.
    - Revise all unit tests that used the legacy test_* macros to
      instead use the recommended tt_* macros. This patch was generated
      with coccinelle, to avoid manual errors. Closes ticket 13119.

  o Distribution (systemd):
    - systemd unit file: only allow tor to write to /var/lib/tor and
      /var/log/tor. The rest of the filesystem is accessible for reading
      only. Patch by intrigeri; resolves ticket 12751.
    - systemd unit file: ensure that the process and all its children
      can never gain new privileges. Patch by intrigeri; resolves
      ticket 12939.
    - systemd unit file: set up /var/run/tor as writable for the Tor
      service. Patch by intrigeri; resolves ticket 13196.

  o Removed features (directory authorities):
    - Remove code that prevented authorities from listing Tor relays
      affected by CVE-2011-2769 as guards. These relays are already
      rejected altogether due to the minimum version requirement of
      0.2.3.16-alpha. Closes ticket 13152.
    - The "AuthDirRejectUnlisted" option no longer has any effect, as
      the fingerprints file (approved-routers) has been deprecated.
    - Directory authorities do not support being Naming dirauths anymore.
      The "NamingAuthoritativeDir" config option is now obsolete.
    - Directory authorities do not support giving out the BadDirectory
      flag anymore.
    - Directory authorities no longer advertise or support consensus
      methods 1 through 12 inclusive. These consensus methods were
      obsolete and/or insecure: maintaining the ability to support them
      served no good purpose. Implements part of proposal 215; closes
      ticket 10163.

  o Testing (test-network.sh):
    - Stop using "echo -n", as some shells' built-in echo doesn't
      support "-n". Instead, use "/bin/echo -n". Partially fixes
      bug 13161.
    - Stop an apparent test-network hang when used with make -j2. Fixes
      bug 13331.
    - Add a --delay option to test-network.sh, which configures the
      delay before the chutney network tests for data transmission.
      Partially implements ticket 13161.


Changes in version 0.2.5.10 - 2014-10-24
  Tor 0.2.5.10 is the first stable release in the 0.2.5 series.

  It adds several new security features, including improved
  denial-of-service resistance for relays, new compiler hardening
  options, and a system-call sandbox for hardened installations on Linux
  (requires seccomp2). The controller protocol has several new features,
  resolving IPv6 addresses should work better than before, and relays
  should be a little more CPU-efficient. We've added support for more
  OpenBSD and FreeBSD transparent proxy types. We've improved the build
  system and testing infrastructure to allow unit testing of more parts
  of the Tor codebase. Finally, we've addressed several nagging pluggable
  transport usability issues, and included numerous other small bugfixes
  and features mentioned below.

  This release marks end-of-life for Tor 0.2.3.x; those Tor versions
  have accumulated many known flaws; everyone should upgrade.

  o Deprecated versions:
    - Tor 0.2.3.x has reached end-of-life; it has received no patches or
      attention for some while.


Changes in version 0.2.5.9-rc - 2014-10-20
  Tor 0.2.5.9-rc is the third release candidate for the Tor 0.2.5.x
  series. It disables SSL3 in response to the recent "POODLE" attack
  (even though POODLE does not affect Tor). It also works around a crash
  bug caused by some operating systems' response to the "POODLE" attack
  (which does affect Tor). It also contains a few miscellaneous fixes.

  o Major security fixes:
    - Disable support for SSLv3. All versions of OpenSSL in use with Tor
      today support TLS 1.0 or later, so we can safely turn off support
      for this old (and insecure) protocol. Fixes bug 13426.

  o Major bugfixes (openssl bug workaround):
    - Avoid crashing when using OpenSSL version 0.9.8zc, 1.0.0o, or
      1.0.1j, built with the 'no-ssl3' configuration option. Fixes bug
      13471. This is a workaround for an OpenSSL bug.

  o Minor bugfixes:
    - Disable the sandbox name resolver cache when running tor-resolve:
      tor-resolve doesn't use the sandbox code, and turning it on was
      breaking attempts to do tor-resolve on a non-default server on
      Linux. Fixes bug 13295; bugfix on 0.2.5.3-alpha.

  o Compilation fixes:
    - Build and run correctly on systems like OpenBSD-current that have
      patched OpenSSL to remove get_cipher_by_char and/or its
      implementations. Fixes issue 13325.

  o Downgraded warnings:
    - Downgrade the severity of the 'unexpected sendme cell from client'
      from 'warn' to 'protocol warning'. Closes ticket 8093.


Changes in version 0.2.4.25 - 2014-10-20
  Tor 0.2.4.25 disables SSL3 in response to the recent "POODLE" attack
  (even though POODLE does not affect Tor). It also works around a crash
  bug caused by some operating systems' response to the "POODLE" attack
  (which does affect Tor).

  o Major security fixes (also in 0.2.5.9-rc):
    - Disable support for SSLv3. All versions of OpenSSL in use with Tor
      today support TLS 1.0 or later, so we can safely turn off support
      for this old (and insecure) protocol. Fixes bug 13426.

  o Major bugfixes (openssl bug workaround, also in 0.2.5.9-rc):
    - Avoid crashing when using OpenSSL version 0.9.8zc, 1.0.0o, or
      1.0.1j, built with the 'no-ssl3' configuration option. Fixes bug
      13471. This is a workaround for an OpenSSL bug.


Changes in version 0.2.5.8-rc - 2014-09-22
  Tor 0.2.5.8-rc is the second release candidate for the Tor 0.2.5.x
  series. It fixes a bug that affects consistency and speed when
  connecting to hidden services, and it updates the location of one of
  the directory authorities.

  o Major bugfixes:
    - Clients now send the correct address for their chosen rendezvous
      point when trying to access a hidden service. They used to send
      the wrong address, which would still work some of the time because
      they also sent the identity digest of the rendezvous point, and if
      the hidden service happened to try connecting to the rendezvous
      point from a relay that already had a connection open to it,
      the relay would reuse that connection. Now connections to hidden
      services should be more robust and faster. Also, this bug meant
      that clients were leaking to the hidden service whether they were
      on a little-endian (common) or big-endian (rare) system, which for
      some users might have reduced their anonymity. Fixes bug 13151;
      bugfix on 0.2.1.5-alpha.

  o Directory authority changes:
    - Change IP address for gabelmoo (v3 directory authority).


Changes in version 0.2.4.24 - 2014-09-22
  Tor 0.2.4.24 fixes a bug that affects consistency and speed when
  connecting to hidden services, and it updates the location of one of
  the directory authorities.

  o Major bugfixes:
    - Clients now send the correct address for their chosen rendezvous
      point when trying to access a hidden service. They used to send
      the wrong address, which would still work some of the time because
      they also sent the identity digest of the rendezvous point, and if
      the hidden service happened to try connecting to the rendezvous
      point from a relay that already had a connection open to it,
      the relay would reuse that connection. Now connections to hidden
      services should be more robust and faster. Also, this bug meant
      that clients were leaking to the hidden service whether they were
      on a little-endian (common) or big-endian (rare) system, which for
      some users might have reduced their anonymity. Fixes bug 13151;
      bugfix on 0.2.1.5-alpha.

  o Directory authority changes:
    - Change IP address for gabelmoo (v3 directory authority).

  o Minor features (geoip):
    - Update geoip and geoip6 to the August 7 2014 Maxmind GeoLite2
      Country database.


Changes in version 0.2.5.7-rc - 2014-09-11
  Tor 0.2.5.7-rc fixes several regressions from earlier in the 0.2.5.x
  release series, and some long-standing bugs related to ORPort reachability
  testing and failure to send CREATE cells. It is the first release
  candidate for the Tor 0.2.5.x series.

  o Major bugfixes (client, startup):
    - Start making circuits as soon as DisabledNetwork is turned off.
      When Tor started with DisabledNetwork set, it would correctly
      conclude that it shouldn't build circuits, but it would mistakenly
      cache this conclusion, and continue believing it even when
      DisableNetwork is set to 0. Fixes the bug introduced by the fix
      for bug 11200; bugfix on 0.2.5.4-alpha.
    - Resume expanding abbreviations for command-line options. The fix
      for bug 4647 accidentally removed our hack from bug 586 that
      rewrote HashedControlPassword to __HashedControlSessionPassword
      when it appears on the commandline (which allowed the user to set
      her own HashedControlPassword in the torrc file while the
      controller generates a fresh session password for each run). Fixes
      bug 12948; bugfix on 0.2.5.1-alpha.
    - Warn about attempts to run hidden services and relays in the same
      process: that's probably not a good idea. Closes ticket 12908.

  o Major bugfixes (relay):
    - Avoid queuing or sending destroy cells for circuit ID zero when we
      fail to send a CREATE cell. Fixes bug 12848; bugfix on 0.0.8pre1.
      Found and fixed by "cypherpunks".
    - Fix ORPort reachability detection on relays running behind a
      proxy, by correctly updating the "local" mark on the controlling
      channel when changing the address of an or_connection_t after the
      handshake. Fixes bug 12160; bugfix on 0.2.4.4-alpha.

  o Minor features (bridge):
    - Add an ExtORPortCookieAuthFileGroupReadable option to make the
      cookie file for the ExtORPort g+r by default.

  o Minor features (geoip):
    - Update geoip and geoip6 to the August 7 2014 Maxmind GeoLite2
      Country database.

  o Minor bugfixes (logging):
    - Reduce the log severity of the "Pluggable transport proxy does not
      provide any needed transports and will not be launched." message,
      since Tor Browser includes several ClientTransportPlugin lines in
      its torrc-defaults file, leading every Tor Browser user who looks
      at her logs to see these notices and wonder if they're dangerous.
      Resolves bug 13124; bugfix on 0.2.5.3-alpha.
    - Downgrade "Unexpected onionskin length after decryption" warning
      to a protocol-warn, since there's nothing relay operators can do
      about a client that sends them a malformed create cell. Resolves
      bug 12996; bugfix on 0.0.6rc1.
    - Log more specific warnings when we get an ESTABLISH_RENDEZVOUS
      cell on a cannibalized or non-OR circuit. Resolves ticket 12997.
    - When logging information about an EXTEND2 or EXTENDED2 cell, log
      their names correctly. Fixes part of bug 12700; bugfix
      on 0.2.4.8-alpha.
    - When logging information about a relay cell whose command we don't
      recognize, log its command as an integer. Fixes part of bug 12700;
      bugfix on 0.2.1.10-alpha.
    - Escape all strings from the directory connection before logging
      them. Fixes bug 13071; bugfix on 0.1.1.15. Patch from "teor".

  o Minor bugfixes (controller):
    - Restore the functionality of CookieAuthFileGroupReadable. Fixes
      bug 12864; bugfix on 0.2.5.1-alpha.
    - Actually send TRANSPORT_LAUNCHED and HS_DESC events to
      controllers. Fixes bug 13085; bugfix on 0.2.5.1-alpha. Patch
      by "teor".

  o Minor bugfixes (compilation):
    - Fix compilation of test.h with MSVC. Patch from Gisle Vanem;
      bugfix on 0.2.5.5-alpha.
    - Make the nmake make files work again. Fixes bug 13081. Bugfix on
      0.2.5.1-alpha. Patch from "NewEraCracker".
    - In routerlist_assert_ok(), don't take the address of a
      routerinfo's cache_info member unless that routerinfo is non-NULL.
      Fixes bug 13096; bugfix on 0.1.1.9-alpha. Patch by "teor".
    - Fix a large number of false positive warnings from the clang
      analyzer static analysis tool. This should make real warnings
      easier for clang analyzer to find. Patch from "teor". Closes
      ticket 13036.

  o Distribution (systemd):
    - Verify configuration file via ExecStartPre in the systemd unit
      file. Patch from intrigeri; resolves ticket 12730.
    - Explicitly disable RunAsDaemon in the systemd unit file. Our
      current systemd unit uses "Type = simple", so systemd does not
      expect tor to fork. If the user has "RunAsDaemon 1" in their
      torrc, then things won't work as expected. This is e.g. the case
      on Debian (and derivatives), since there we pass "--defaults-torrc
      /usr/share/tor/tor-service-defaults-torrc" (that contains
      "RunAsDaemon 1") by default. Patch by intrigeri; resolves
      ticket 12731.

  o Documentation:
    - Adjust the URLs in the README to refer to the new locations of
      several documents on the website. Fixes bug 12830. Patch from
      Matt Pagan.
    - Document 'reject6' and 'accept6' ExitPolicy entries. Resolves
      ticket 12878.


Changes in version 0.2.5.6-alpha - 2014-07-28
  Tor 0.2.5.6-alpha brings us a big step closer to slowing down the
  risk from guard rotation, and fixes a variety of other issues to get
  us closer to a release candidate.

  o Major features (also in 0.2.4.23):
    - Make the number of entry guards configurable via a new
      NumEntryGuards consensus parameter, and the number of directory
      guards configurable via a new NumDirectoryGuards consensus
      parameter. Implements ticket 12688.

  o Major bugfixes (also in 0.2.4.23):
    - Fix a bug in the bounds-checking in the 32-bit curve25519-donna
      implementation that caused incorrect results on 32-bit
      implementations when certain malformed inputs were used along with
      a small class of private ntor keys. This bug does not currently
      appear to allow an attacker to learn private keys or impersonate a
      Tor server, but it could provide a means to distinguish 32-bit Tor
      implementations from 64-bit Tor implementations. Fixes bug 12694;
      bugfix on 0.2.4.8-alpha. Bug found by Robert Ransom; fix from
      Adam Langley.

  o Major bugfixes:
    - Perform circuit cleanup operations even when circuit
      construction operations are disabled (because the network is
      disabled, or because there isn't enough directory information).
      Previously, when we were not building predictive circuits, we
      were not closing expired circuits either. Fixes bug 8387; bugfix on
      0.1.1.11-alpha. This bug became visible in 0.2.4.10-alpha when we
      became more strict about when we have "enough directory information
      to build circuits".

  o Minor features:
    - Authorities now assign the Guard flag to the fastest 25% of the
      network (it used to be the fastest 50%). Also raise the consensus
      weight that guarantees the Guard flag from 250 to 2000. For the
      current network, this results in about 1100 guards, down from 2500.
      This step paves the way for moving the number of entry guards
      down to 1 (proposal 236) while still providing reasonable expected
      performance for most users. Implements ticket 12690.
    - Update geoip and geoip6 to the July 10 2014 Maxmind GeoLite2
      Country database.
    - Slightly enhance the diagnostic message for bug 12184.

  o Minor bugfixes (also in 0.2.4.23):
    - Warn and drop the circuit if we receive an inbound 'relay early'
      cell. Those used to be normal to receive on hidden service circuits
      due to bug 1038, but the buggy Tor versions are long gone from
      the network so we can afford to resume watching for them. Resolves
      the rest of bug 1038; bugfix on 0.2.1.19.
    - Correct a confusing error message when trying to extend a circuit
      via the control protocol but we don't know a descriptor or
      microdescriptor for one of the specified relays. Fixes bug 12718;
      bugfix on 0.2.3.1-alpha.

  o Minor bugfixes:
    - Fix compilation when building with bufferevents enabled. (This
      configuration is still not expected to work, however.)
      Fixes bugs 12438, 12474, 11578; bugfixes on 0.2.5.1-alpha and
      0.2.5.3-alpha. Patches from Anthony G. Basile and Sathyanarayanan
      Gunasekaran.
    - Compile correctly with builds and forks of OpenSSL (such as
      LibreSSL) that disable compression. Fixes bug 12602; bugfix on
      0.2.1.1-alpha. Patch from "dhill".


Changes in version 0.2.4.23 - 2014-07-28
  Tor 0.2.4.23 brings us a big step closer to slowing down the risk from
  guard rotation, and also backports several important fixes from the
  Tor 0.2.5 alpha release series.

  o Major features:
    - Clients now look at the "usecreatefast" consensus parameter to
      decide whether to use CREATE_FAST or CREATE cells for the first hop
      of their circuit. This approach can improve security on connections
      where Tor's circuit handshake is stronger than the available TLS
      connection security levels, but the tradeoff is more computational
      load on guard relays. Implements proposal 221. Resolves ticket 9386.
    - Make the number of entry guards configurable via a new
      NumEntryGuards consensus parameter, and the number of directory
      guards configurable via a new NumDirectoryGuards consensus
      parameter. Implements ticket 12688.

  o Major bugfixes:
    - Fix a bug in the bounds-checking in the 32-bit curve25519-donna
      implementation that caused incorrect results on 32-bit
      implementations when certain malformed inputs were used along with
      a small class of private ntor keys. This bug does not currently
      appear to allow an attacker to learn private keys or impersonate a
      Tor server, but it could provide a means to distinguish 32-bit Tor
      implementations from 64-bit Tor implementations. Fixes bug 12694;
      bugfix on 0.2.4.8-alpha. Bug found by Robert Ransom; fix from
      Adam Langley.

  o Minor bugfixes:
    - Warn and drop the circuit if we receive an inbound 'relay early'
      cell. Those used to be normal to receive on hidden service circuits
      due to bug 1038, but the buggy Tor versions are long gone from
      the network so we can afford to resume watching for them. Resolves
      the rest of bug 1038; bugfix on 0.2.1.19.
    - Correct a confusing error message when trying to extend a circuit
      via the control protocol but we don't know a descriptor or
      microdescriptor for one of the specified relays. Fixes bug 12718;
      bugfix on 0.2.3.1-alpha.
    - Avoid an illegal read from stack when initializing the TLS
      module using a version of OpenSSL without all of the ciphers
      used by the v2 link handshake. Fixes bug 12227; bugfix on
      0.2.4.8-alpha.  Found by "starlight".

  o Minor features:
    - Update geoip and geoip6 to the July 10 2014 Maxmind GeoLite2
      Country database.


Changes in version 0.2.5.5-alpha - 2014-06-18
  Tor 0.2.5.5-alpha fixes a wide variety of remaining issues in the Tor
  0.2.5.x release series, including a couple of DoS issues, some
  performance regressions, a large number of bugs affecting the Linux
  seccomp2 sandbox code, and various other bugfixes. It also adds
  diagnostic bugfixes for a few tricky issues that we're trying to
  track down.

  o Major features (security, traffic analysis resistance):
    - Several major improvements to the algorithm used to decide when to
      close TLS connections. Previous versions of Tor closed connections
      at a fixed interval after the last time a non-padding cell was
      sent over the connection, regardless of the target of the
      connection. Now, we randomize the intervals by adding up to 50% of
      their base value, we measure the length of time since connection
      last had at least one circuit, and we allow connections to known
      ORs to remain open a little longer (15 minutes instead of 3
      minutes minimum). These changes should improve Tor's resistance
      against some kinds of traffic analysis, and lower some overhead
      from needlessly closed connections. Fixes ticket 6799.
      Incidentally fixes ticket 12023; bugfix on 0.2.5.1-alpha.

  o Major bugfixes (security, OOM, new since 0.2.5.4-alpha, also in 0.2.4.22):
    - Fix a memory leak that could occur if a microdescriptor parse
      fails during the tokenizing step. This bug could enable a memory
      exhaustion attack by directory servers. Fixes bug 11649; bugfix
      on 0.2.2.6-alpha.

  o Major bugfixes (security, directory authorities):
    - Directory authorities now include a digest of each relay's
      identity key as a part of its microdescriptor.

      This is a workaround for bug 11743 (reported by "cypherpunks"),
      where Tor clients do not support receiving multiple
      microdescriptors with the same SHA256 digest in the same
      consensus. When clients receive a consensus like this, they only
      use one of the relays. Without this fix, a hostile relay could
      selectively disable some client use of target relays by
      constructing a router descriptor with a different identity and the
      same microdescriptor parameters and getting the authorities to
      list it in a microdescriptor consensus. This fix prevents an
      attacker from causing a microdescriptor collision, because the
      router's identity is not forgeable.

  o Major bugfixes (relay):
    - Use a direct dirport connection when uploading non-anonymous
      descriptors to the directory authorities. Previously, relays would
      incorrectly use tunnel connections under a fairly wide variety of
      circumstances. Fixes bug 11469; bugfix on 0.2.4.3-alpha.
    - When a circuit accidentally has the same circuit ID for its
      forward and reverse direction, correctly detect the direction of
      cells using that circuit. Previously, this bug made roughly one
      circuit in a million non-functional. Fixes bug 12195; this is a
      bugfix on every version of Tor.

  o Major bugfixes (client, pluggable transports):
    - When managing pluggable transports, use OS notification facilities
      to learn if they have crashed, and don't attempt to kill any
      process that has already exited. Fixes bug 8746; bugfix
      on 0.2.3.6-alpha.

  o Minor features (diagnostic):
    - When logging a warning because of bug 7164, additionally check the
      hash table for consistency (as proposed on ticket 11737). This may
      help diagnose bug 7164.
    - When we log a heartbeat, log how many one-hop circuits we have
      that are at least 30 minutes old, and log status information about
      a few of them. This is an attempt to track down bug 8387.
    - When encountering an unexpected CR while writing text to a file on
      Windows, log the name of the file. Should help diagnosing
      bug 11233.
    - Give more specific warnings when a client notices that an onion
      handshake has failed. Fixes ticket 9635.
    - Add significant new logging code to attempt to diagnose bug 12184,
      where relays seem to run out of available circuit IDs.
    - Improve the diagnostic log message for bug 8387 even further to
      try to improve our odds of figuring out why one-hop directory
      circuits sometimes do not get closed.

  o Minor features (security, memory management):
    - Memory allocation tricks (mempools and buffer freelists) are now
      disabled by default. You can turn them back on with
      --enable-mempools and --enable-buf-freelists respectively. We're
      disabling these features because malloc performance is good enough
      on most platforms, and a similar feature in OpenSSL exacerbated
      exploitation of the Heartbleed attack. Resolves ticket 11476.

  o Minor features (security):
    - Apply the secure SipHash-2-4 function to the hash table mapping
      circuit IDs and channels to circuits. We missed this one when we
      were converting all the other hash functions to use SipHash back
      in 0.2.5.3-alpha. Resolves ticket 11750.

  o Minor features (build):
    - The configure script has a --disable-seccomp option to turn off
      support for libseccomp on systems that have it, in case it (or
      Tor's use of it) is broken. Resolves ticket 11628.

  o Minor features (other):
    - Update geoip and geoip6 to the June 4 2014 Maxmind GeoLite2
      Country database.

  o Minor bugfixes (security, new since 0.2.5.4-alpha, also in 0.2.4.22):
    - When running a hidden service, do not allow TunneledDirConns 0;
      this will keep the hidden service from running, and also
      make it publish its descriptors directly over HTTP. Fixes bug 10849;
      bugfix on 0.2.1.1-alpha.

  o Minor bugfixes (performance):
    - Avoid a bug where every successful connection made us recompute
      the flag telling us whether we have sufficient information to
      build circuits. Previously, we would forget our cached value
      whenever we successfully opened a channel (or marked a router as
      running or not running for any other reason), regardless of
      whether we had previously believed the router to be running. This
      forced us to run an expensive update operation far too often.
      Fixes bug 12170; bugfix on 0.1.2.1-alpha.
    - Avoid using tor_memeq() for checking relay cell integrity. This
      removes a possible performance bottleneck. Fixes part of bug
      12169; bugfix on 0.2.1.31.

  o Minor bugfixes (compilation):
    - Fix compilation of test_status.c when building with MVSC. Bugfix
      on 0.2.5.4-alpha. Patch from Gisle Vanem.
    - Resolve GCC complaints on OpenBSD about discarding constness in
      TO_{ORIGIN,OR}_CIRCUIT functions. Fixes part of bug 11633; bugfix
      on 0.1.1.23. Patch from Dana Koch.
    - Resolve clang complaints on OpenBSD with -Wshorten-64-to-32 due to
      treatment of long and time_t as comparable types. Fixes part of
      bug 11633. Patch from Dana Koch.
    - Make Tor compile correctly with --disable-buf-freelists. Fixes bug
      11623; bugfix on 0.2.5.3-alpha.
    - When deciding whether to build the 64-bit curve25519
      implementation, detect platforms where we can compile 128-bit
      arithmetic but cannot link it. Fixes bug 11729; bugfix on
      0.2.4.8-alpha. Patch from "conradev".
    - Fix compilation when DNS_CACHE_DEBUG is enabled. Fixes bug 11761;
      bugfix on 0.2.3.13-alpha. Found by "cypherpunks".
    - Fix compilation with dmalloc. Fixes bug 11605; bugfix
      on 0.2.4.10-alpha.

  o Minor bugfixes (Directory server):
    - When sending a compressed set of descriptors or microdescriptors,
      make sure to finalize the zlib stream. Previously, we would write
      all the compressed data, but if the last descriptor we wanted to
      send was missing or too old, we would not mark the stream as
      finished. This caused problems for decompression tools. Fixes bug
      11648; bugfix on 0.1.1.23.

  o Minor bugfixes (Linux seccomp sandbox):
    - Make the seccomp sandbox code compile under ARM Linux. Fixes bug
      11622; bugfix on 0.2.5.1-alpha.
    - Avoid crashing when re-opening listener ports with the seccomp
      sandbox active. Fixes bug 12115; bugfix on 0.2.5.1-alpha.
    - Avoid crashing with the seccomp sandbox enabled along with
      ConstrainedSockets. Fixes bug 12139; bugfix on 0.2.5.1-alpha.
    - When we receive a SIGHUP with the sandbox enabled, correctly
      support rotating our log files. Fixes bug 12032; bugfix
      on 0.2.5.1-alpha.
    - Avoid crash when running with sandboxing enabled and
      DirReqStatistics not disabled. Fixes bug 12035; bugfix
      on 0.2.5.1-alpha.
    - Fix a "BUG" warning when trying to write bridge-stats files with
      the Linux syscall sandbox filter enabled. Fixes bug 12041; bugfix
      on 0.2.5.1-alpha.
    - Prevent the sandbox from crashing on startup when run with the
      --enable-expensive-hardening configuration option. Fixes bug
      11477; bugfix on 0.2.5.4-alpha.
    - When running with DirPortFrontPage and sandboxing both enabled,
      reload the DirPortFrontPage correctly when restarting. Fixes bug
      12028; bugfix on 0.2.5.1-alpha.
    - Don't try to enable the sandbox when using the Tor binary to check
      its configuration, hash a passphrase, or so on. Doing so was
      crashing on startup for some users. Fixes bug 11609; bugfix
      on 0.2.5.1-alpha.
    - Avoid warnings when running with sandboxing and node statistics
      enabled at the same time. Fixes part of 12064; bugfix on
      0.2.5.1-alpha. Patch from Michael Wolf.
    - Avoid warnings when running with sandboxing enabled at the same
      time as cookie authentication, hidden services, or directory
      authority voting. Fixes part of 12064; bugfix on 0.2.5.1-alpha.
    - Do not allow options that require calls to exec to be enabled
      alongside the seccomp2 sandbox: they will inevitably crash. Fixes
      bug 12043; bugfix on 0.2.5.1-alpha.
    - Handle failures in getpwnam()/getpwuid() when running with the
      User option set and the Linux syscall sandbox enabled. Fixes bug
      11946; bugfix on 0.2.5.1-alpha.
    - Refactor the getaddrinfo workaround that the seccomp sandbox uses
      to avoid calling getaddrinfo() after installing the sandbox
      filters. Previously, it preloaded a cache with the IPv4 address
      for our hostname, and nothing else. Now, it loads the cache with
      every address that it used to initialize the Tor process. Fixes
      bug 11970; bugfix on 0.2.5.1-alpha.

  o Minor bugfixes (pluggable transports):
    - Enable the ExtORPortCookieAuthFile option, to allow changing the
      default location of the authentication token for the extended OR
      Port as used by sever-side pluggable transports. We had
      implemented this option before, but the code to make it settable
      had been omitted. Fixes bug 11635; bugfix on 0.2.5.1-alpha.
    - Avoid another 60-second delay when starting Tor in a pluggable-
      transport-using configuration when we already have cached
      descriptors for our bridges. Fixes bug 11965; bugfix
      on 0.2.3.6-alpha.

  o Minor bugfixes (client):
    - Avoid "Tried to open a socket with DisableNetwork set" warnings
      when starting a client with bridges configured and DisableNetwork
      set. (Tor launcher starts Tor with DisableNetwork set the first
      time it runs.) Fixes bug 10405; bugfix on 0.2.3.9-alpha.

  o Minor bugfixes (testing):
    - The Python parts of the test scripts now work on Python 3 as well
      as Python 2, so systems where '/usr/bin/python' is Python 3 will
      no longer have the tests break. Fixes bug 11608; bugfix
      on 0.2.5.2-alpha.
    - When looking for versions of python that we could run the tests
      with, check for "python2.7" and "python3.3"; previously we were
      only looking for "python", "python2", and "python3". Patch from
      Dana Koch. Fixes bug 11632; bugfix on 0.2.5.2-alpha.
    - Fix all valgrind warnings produced by the unit tests. There were
      over a thousand memory leak warnings previously, mostly produced
      by forgetting to free things in the unit test code. Fixes bug
      11618, bugfixes on many versions of Tor.

  o Minor bugfixes (tor-fw-helper):
    - Give a correct log message when tor-fw-helper fails to launch.
      (Previously, we would say something like "tor-fw-helper sent us a
      string we could not parse".) Fixes bug 9781; bugfix
      on 0.2.4.2-alpha.

  o Minor bugfixes (relay, threading):
    - Check return code on spawn_func() in cpuworker code, so that we
      don't think we've spawned a nonworking cpuworker and write junk to
      it forever. Fix related to bug 4345; bugfix on all released Tor
      versions. Found by "skruffy".
    - Use a pthread_attr to make sure that spawn_func() cannot return an
      error while at the same time launching a thread. Fix related to
      bug 4345; bugfix on all released Tor versions. Reported
      by "cypherpunks".

  o Minor bugfixes (relay, oom prevention):
    - Correctly detect the total available system memory. We tried to do
      this in 0.2.5.4-alpha, but the code was set up to always return an
      error value, even on success. Fixes bug 11805; bugfix
      on 0.2.5.4-alpha.

  o Minor bugfixes (relay, other):
    - We now drop CREATE cells for already-existent circuit IDs and for
      zero-valued circuit IDs, regardless of other factors that might
      otherwise have called for DESTROY cells. Fixes bug 12191; bugfix
      on 0.0.8pre1.
    - Avoid an illegal read from stack when initializing the TLS module
      using a version of OpenSSL without all of the ciphers used by the
      v2 link handshake. Fixes bug 12227; bugfix on 0.2.4.8-alpha. Found
      by "starlight".
    - When rejecting DATA cells for stream_id zero, still count them
      against the circuit's deliver window so that we don't fail to send
      a SENDME. Fixes bug 11246; bugfix on 0.2.4.10-alpha.

  o Minor bugfixes (logging):
    - Fix a misformatted log message about delayed directory fetches.
      Fixes bug 11654; bugfix on 0.2.5.3-alpha.
    - Squelch a spurious LD_BUG message "No origin circuit for
      successful SOCKS stream" in certain hidden service failure cases;
      fixes bug 10616.

  o Distribution:
    - Include a tor.service file in contrib/dist for use with systemd.
      Some distributions will be able to use this file unmodified;
      others will need to tweak it, or write their own. Patch from Jamie
      Nguyen; resolves ticket 8368.

  o Documentation:
    - Clean up several option names in the manpage to match their real
      names, add the missing documentation for a couple of testing and
      directory authority options, remove the documentation for a
      V2-directory fetching option that no longer exists. Resolves
      ticket 11634.
    - Correct the documentation so that it lists the correct directory
      for the stats files. (They are in a subdirectory called "stats",
      not "status".)
    - In the manpage, move more authority-only options into the
      directory authority section so that operators of regular directory
      caches don't get confused.

  o Package cleanup:
    - The contrib directory has been sorted and tidied. Before, it was
      an unsorted dumping ground for useful and not-so-useful things.
      Now, it is divided based on functionality, and the items which
      seemed to be nonfunctional or useless have been removed. Resolves
      ticket 8966; based on patches from "rl1987".

  o Removed code:
    - Remove /tor/dbg-stability.txt URL that was meant to help debug WFU
      and MTBF calculations, but that nobody was using. Fixes ticket 11742.
    - The TunnelDirConns and PreferTunnelledDirConns options no longer
      exist; tunneled directory connections have been available since
      0.1.2.5-alpha, and turning them off is not a good idea. This is a
      brute-force fix for 10849, where "TunnelDirConns 0" would break
      hidden services.


Changes in version 0.2.4.22 - 2014-05-16
  Tor 0.2.4.22 backports numerous high-priority fixes from the Tor 0.2.5
  alpha release series. These include blocking all authority signing
  keys that may have been affected by the OpenSSL "heartbleed" bug,
  choosing a far more secure set of TLS ciphersuites by default, closing
  a couple of memory leaks that could be used to run a target relay out
  of RAM, and several others.

  o Major features (security, backport from 0.2.5.4-alpha):
    - Block authority signing keys that were used on authorities
      vulnerable to the "heartbleed" bug in OpenSSL (CVE-2014-0160). (We
      don't have any evidence that these keys _were_ compromised; we're
      doing this to be prudent.) Resolves ticket 11464.

  o Major bugfixes (security, OOM):
    - Fix a memory leak that could occur if a microdescriptor parse
      fails during the tokenizing step. This bug could enable a memory
      exhaustion attack by directory servers. Fixes bug 11649; bugfix
      on 0.2.2.6-alpha.

  o Major bugfixes (TLS cipher selection, backport from 0.2.5.4-alpha):
    - The relay ciphersuite list is now generated automatically based on
      uniform criteria, and includes all OpenSSL ciphersuites with
      acceptable strength and forward secrecy. Previously, we had left
      some perfectly fine ciphersuites unsupported due to omission or
      typo. Resolves bugs 11513, 11492, 11498, 11499. Bugs reported by
      'cypherpunks'. Bugfix on 0.2.4.8-alpha.
    - Relays now trust themselves to have a better view than clients of
      which TLS ciphersuites are better than others. (Thanks to bug
      11513, the relay list is now well-considered, whereas the client
      list has been chosen mainly for anti-fingerprinting purposes.)
      Relays prefer: AES over 3DES; then ECDHE over DHE; then GCM over
      CBC; then SHA384 over SHA256 over SHA1; and last, AES256 over
      AES128. Resolves ticket 11528.
    - Clients now try to advertise the same list of ciphersuites as
      Firefox 28. This change enables selection of (fast) GCM
      ciphersuites, disables some strange old ciphers, and stops
      advertising the ECDH (not to be confused with ECDHE) ciphersuites.
      Resolves ticket 11438.

  o Minor bugfixes (configuration, security):
    - When running a hidden service, do not allow TunneledDirConns 0:
      trying to set that option together with a hidden service would
      otherwise prevent the hidden service from running, and also make
      it publish its descriptors directly over HTTP. Fixes bug 10849;
      bugfix on 0.2.1.1-alpha.

  o Minor bugfixes (controller, backport from 0.2.5.4-alpha):
    - Avoid sending a garbage value to the controller when a circuit is
      cannibalized. Fixes bug 11519; bugfix on 0.2.3.11-alpha.

  o Minor bugfixes (exit relay, backport from 0.2.5.4-alpha):
    - Stop leaking memory when we successfully resolve a PTR record.
      Fixes bug 11437; bugfix on 0.2.4.7-alpha.

  o Minor bugfixes (bridge client, backport from 0.2.5.4-alpha):
    - Avoid 60-second delays in the bootstrapping process when Tor is
      launching for a second time while using bridges. Fixes bug 9229;
      bugfix on 0.2.0.3-alpha.

  o Minor bugfixes (relays and bridges, backport from 0.2.5.4-alpha):
    - Give the correct URL in the warning message when trying to run a
      relay on an ancient version of Windows. Fixes bug 9393.

  o Minor bugfixes (compilation):
    - Fix a compilation error when compiling with --disable-curve25519.
      Fixes bug 9700; bugfix on 0.2.4.17-rc.

  o Minor bugfixes:
    - Downgrade the warning severity for the the "md was still
      referenced 1 node(s)" warning. Tor 0.2.5.4-alpha has better code
      for trying to diagnose this bug, and the current warning in
      earlier versions of tor achieves nothing useful. Addresses warning
      from bug 7164.

  o Minor features (log verbosity, backport from 0.2.5.4-alpha):
    - When we run out of usable circuit IDs on a channel, log only one
      warning for the whole channel, and describe how many circuits
      there were on the channel. Fixes part of ticket 11553.

  o Minor features (security, backport from 0.2.5.4-alpha):
    - Decrease the lower limit of MaxMemInCellQueues to 256 MBytes (but
      leave the default at 8GBytes), to better support Raspberry Pi
      users. Fixes bug 9686; bugfix on 0.2.4.14-alpha.

  o Documentation (backport from 0.2.5.4-alpha):
    - Correctly document that we search for a system torrc file before
      looking in ~/.torrc. Fixes documentation side of 9213; bugfix on
      0.2.3.18-rc.


Changes in version 0.2.5.4-alpha - 2014-04-25
  Tor 0.2.5.4-alpha includes several security and performance
  improvements for clients and relays, including blacklisting authority
  signing keys that were used while susceptible to the OpenSSL
  "heartbleed" bug, fixing two expensive functions on busy relays,
  improved TLS ciphersuite preference lists, support for run-time
  hardening on compilers that support AddressSanitizer, and more work on
  the Linux sandbox code.

  There are also several usability fixes for clients (especially clients
  that use bridges), two new TransPort protocols supported (one on
  OpenBSD, one on FreeBSD), and various other bugfixes.

  This release marks end-of-life for Tor 0.2.2.x; those Tor versions
  have accumulated many known flaws; everyone should upgrade.

  o Major features (security):
    - If you don't specify MaxMemInQueues yourself, Tor now tries to
      pick a good value based on your total system memory. Previously,
      the default was always 8 GB. You can still override the default by
      setting MaxMemInQueues yourself. Resolves ticket 11396.
    - Block authority signing keys that were used on authorities
      vulnerable to the "heartbleed" bug in OpenSSL (CVE-2014-0160). (We
      don't have any evidence that these keys _were_ compromised; we're
      doing this to be prudent.) Resolves ticket 11464.

  o Major features (relay performance):
    - Speed up server-side lookups of rendezvous and introduction point
      circuits by using hashtables instead of linear searches. These
      functions previously accounted between 3 and 7% of CPU usage on
      some busy relays. Resolves ticket 9841.
    - Avoid wasting CPU when extending a circuit over a channel that is
      nearly out of circuit IDs. Previously, we would do a linear scan
      over possible circuit IDs before finding one or deciding that we
      had exhausted our possibilities. Now, we try at most 64 random
      circuit IDs before deciding that we probably won't succeed. Fixes
      a possible root cause of ticket 11553.

  o Major features (seccomp2 sandbox, Linux only):
    - The seccomp2 sandbox can now run a test network for multiple hours
      without crashing. The sandbox is still experimental, and more bugs
      will probably turn up. To try it, enable "Sandbox 1" on a Linux
      host. Resolves ticket 11351.
    - Strengthen sandbox code: the sandbox can now test the arguments
      for rename(), and blocks _sysctl() entirely. Resolves another part
      of ticket 11351.
    - When the sandbox blocks a system call, it now tries to log a stack
      trace before exiting. Resolves ticket 11465.

  o Major bugfixes (TLS cipher selection):
    - The relay ciphersuite list is now generated automatically based on
      uniform criteria, and includes all OpenSSL ciphersuites with
      acceptable strength and forward secrecy. Previously, we had left
      some perfectly fine ciphersuites unsupported due to omission or
      typo. Resolves bugs 11513, 11492, 11498, 11499. Bugs reported by
      'cypherpunks'. Bugfix on 0.2.4.8-alpha.
    - Relays now trust themselves to have a better view than clients of
      which TLS ciphersuites are better than others. (Thanks to bug
      11513, the relay list is now well-considered, whereas the client
      list has been chosen mainly for anti-fingerprinting purposes.)
      Relays prefer: AES over 3DES; then ECDHE over DHE; then GCM over
      CBC; then SHA384 over SHA256 over SHA1; and last, AES256 over
      AES128. Resolves ticket 11528.
    - Clients now try to advertise the same list of ciphersuites as
      Firefox 28. This change enables selection of (fast) GCM
      ciphersuites, disables some strange old ciphers, and stops
      advertising the ECDH (not to be confused with ECDHE) ciphersuites.
      Resolves ticket 11438.

  o Major bugfixes (bridge client):
    - Avoid 60-second delays in the bootstrapping process when Tor is
      launching for a second time while using bridges. Fixes bug 9229;
      bugfix on 0.2.0.3-alpha.

  o Minor features (transparent proxy, *BSD):
    - Support FreeBSD's ipfw firewall interface for TransPort ports on
      FreeBSD. To enable it, set "TransProxyType ipfw". Resolves ticket
      10267; patch from "yurivict".
    - Support OpenBSD's divert-to rules with the pf firewall for
      transparent proxy ports. To enable it, set "TransProxyType
      pf-divert". This allows Tor to run a TransPort transparent proxy
      port on OpenBSD 4.4 or later without root privileges. See the
      pf.conf(5) manual page for information on configuring pf to use
      divert-to rules. Closes ticket 10896; patch from Dana Koch.

  o Minor features (security):
    - New --enable-expensive-hardening option to enable security
      hardening options that consume nontrivial amounts of CPU and
      memory. Right now, this includes AddressSanitizer and UbSan, which
      are supported in newer versions of GCC and Clang. Closes ticket
      11477.

  o Minor features (log verbosity):
    - Demote the message that we give when a flushing connection times
      out for too long from NOTICE to INFO. It was usually meaningless.
      Resolves ticket 5286.
    - Don't log so many notice-level bootstrapping messages at startup
      about downloading descriptors. Previously, we'd log a notice
      whenever we learned about more routers. Now, we only log a notice
      at every 5% of progress. Fixes bug 9963.
    - Warn less verbosely when receiving a malformed
      ESTABLISH_RENDEZVOUS cell. Fixes ticket 11279.
    - When we run out of usable circuit IDs on a channel, log only one
      warning for the whole channel, and describe how many circuits
      there were on the channel. Fixes part of ticket 11553.

  o Minor features (relay):
    - If a circuit timed out for at least 3 minutes, check if we have a
      new external IP address, and publish a new descriptor with the new
      IP address if it changed. Resolves ticket 2454.

  o Minor features (controller):
    - Make the entire exit policy available from the control port via
      GETINFO exit-policy/*. Implements enhancement 7952. Patch from
      "rl1987".
    - Because of the fix for ticket 11396, the real limit for memory
      usage may no longer match the configured MaxMemInQueues value. The
      real limit is now exposed via GETINFO limits/max-mem-in-queues.

  o Minor features (bridge client):
    - Report a more useful failure message when we can't connect to a
      bridge because we don't have the right pluggable transport
      configured. Resolves ticket 9665. Patch from Fábio J. Bertinatto.

  o Minor features (diagnostic):
    - Add more log messages to diagnose bug 7164, which causes
      intermittent "microdesc_free() called but md was still referenced"
      warnings. We now include more information, to figure out why we
      might be cleaning a microdescriptor for being too old if it's
      still referenced by a live node_t object.

  o Minor bugfixes (client, DNSPort):
    - When using DNSPort, try to respond to AAAA requests with AAAA
      answers. Previously, we hadn't looked at the request type when
      deciding which answer type to prefer. Fixes bug 10468; bugfix on
      0.2.4.7-alpha.
    - When receiving a DNS query for an unsupported record type, reply
      with no answer rather than with a NOTIMPL error. This behavior
      isn't correct either, but it will break fewer client programs, we
      hope. Fixes bug 10268; bugfix on 0.2.0.1-alpha. Original patch
      from "epoch".

  o Minor bugfixes (exit relay):
    - Stop leaking memory when we successfully resolve a PTR record.
      Fixes bug 11437; bugfix on 0.2.4.7-alpha.

  o Minor bugfixes (bridge client):
    - Stop accepting bridge lines containing hostnames. Doing so would
      cause clients to perform DNS requests on the hostnames, which was
      not sensible behavior. Fixes bug 10801; bugfix on 0.2.0.1-alpha.
    - Avoid a 60-second delay in the bootstrapping process when a Tor
      client with pluggable transports re-reads its configuration at
      just the wrong time. Re-fixes bug 11156; bugfix on 0.2.5.3-alpha.

  o Minor bugfixes (client, logging during bootstrap):
    - Warn only once if we start logging in an unsafe way. Previously,
      we complain as many times as we had problems. Fixes bug 9870;
      bugfix on 0.2.5.1-alpha.
    - Only report the first fatal bootstrap error on a given OR
      connection. This stops us from telling the controller bogus error
      messages like "DONE". Fixes bug 10431; bugfix on 0.2.1.1-alpha.
    - Be more helpful when trying to run sandboxed on Linux without
      libseccomp. Instead of saying "Sandbox is not implemented on this
      platform", we now explain that we need to be built with
      libseccomp. Fixes bug 11543; bugfix on 0.2.5.1-alpha.
    - Avoid generating spurious warnings when starting with
      DisableNetwork enabled. Fixes bug 11200 and bug 10405; bugfix on
      0.2.3.9-alpha.

  o Minor bugfixes (closing OR connections):
    - If write_to_buf() in connection_write_to_buf_impl_() ever fails,
      check if it's an or_connection_t and correctly call
      connection_or_close_for_error() rather than
      connection_mark_for_close() directly. Fixes bug 11304; bugfix on
      0.2.4.4-alpha.
    - When closing all connections on setting DisableNetwork to 1, use
      connection_or_close_normally() rather than closing OR connections
      out from under the channel layer. Fixes bug 11306; bugfix on
      0.2.4.4-alpha.

  o Minor bugfixes (controller):
    - Avoid sending a garbage value to the controller when a circuit is
      cannibalized. Fixes bug 11519; bugfix on 0.2.3.11-alpha.

  o Minor bugfixes (tor-fw-helper):
    - Allow tor-fw-helper to build again by adding src/ext to its
      CPPFLAGS. Fixes bug 11296; bugfix on 0.2.5.3-alpha.

  o Minor bugfixes (bridges):
    - Avoid potential crashes or bad behavior when launching a
      server-side managed proxy with ORPort or ExtORPort temporarily
      disabled. Fixes bug 9650; bugfix on 0.2.3.16-alpha.

  o Minor bugfixes (platform-specific):
    - Fix compilation on Solaris, which does not have . Fixes
      bug 11426; bugfix on 0.2.5.3-alpha.
    - When dumping a malformed directory object to disk, save it in
      binary mode on Windows, not text mode. Fixes bug 11342; bugfix on
      0.2.2.1-alpha.
    - Don't report failures from make_socket_reuseable() on incoming
      sockets on OSX: this can happen when incoming connections close
      early. Fixes bug 10081.

  o Minor bugfixes (trivial memory leaks):
    - Fix a small memory leak when signing a directory object. Fixes bug
      11275; bugfix on 0.2.4.13-alpha.
    - Free placeholder entries in our circuit table at exit; fixes a
      harmless memory leak. Fixes bug 11278; bugfix on 0.2.5.1-alpha.
    - Don't re-initialize a second set of OpenSSL mutexes when starting
      up. Previously, we'd make one set of mutexes, and then immediately
      replace them with another. Fixes bug 11726; bugfix on
      0.2.5.3-alpha.
    - Resolve some memory leaks found by coverity in the unit tests, on
      exit in tor-gencert, and on a failure to compute digests for our
      own keys when generating a v3 networkstatus vote. These leaks
      should never have affected anyone in practice.

  o Minor bugfixes (hidden service):
    - Only retry attempts to connect to a chosen rendezvous point 8
      times, not 30. Fixes bug 4241; bugfix on 0.1.0.1-rc.

  o Minor bugfixes (misc code correctness):
    - Fix various instances of undefined behavior in channeltls.c,
      tor_memmem(), and eventdns.c that would cause us to construct
      pointers to memory outside an allocated object. (These invalid
      pointers were not accessed, but C does not even allow them to
      exist.) Fixes bug 10363; bugfixes on 0.1.1.1-alpha, 0.1.2.1-alpha,
      0.2.0.10-alpha, and 0.2.3.6-alpha. Reported by "bobnomnom".
    - Use the AddressSanitizer and Ubsan sanitizers (in clang-3.4) to
      fix some miscellaneous errors in our tests and codebase. Fixes bug
      11232. Bugfixes on versions back as far as 0.2.1.11-alpha.
    - Always check return values for unlink, munmap, UnmapViewOfFile;
      check strftime return values more often. In some cases all we can
      do is report a warning, but this may help prevent deeper bugs from
      going unnoticed. Closes ticket 8787; bugfixes on many, many tor
      versions.
    - Fix numerous warnings from the clang "scan-build" static analyzer.
      Some of these are programming style issues; some of them are false
      positives that indicated awkward code; some are undefined behavior
      cases related to constructing (but not using) invalid pointers;
      some are assumptions about API behavior; some are (harmlessly)
      logging sizeof(ptr) bytes from a token when sizeof(*ptr) would be
      correct; and one or two are genuine bugs that weren't reachable
      from the rest of the program. Fixes bug 8793; bugfixes on many,
      many tor versions.

  o Documentation:
    - Build the torify.1 manpage again. Previously, we were only trying
      to build it when also building tor-fw-helper. That's why we didn't
      notice that we'd broken the ability to build it. Fixes bug 11321;
      bugfix on 0.2.5.1-alpha.
    - Fix the layout of the SOCKSPort flags in the manpage. Fixes bug
      11061; bugfix on 0.2.4.7-alpha.
    - Correctly document that we search for a system torrc file before
      looking in ~/.torrc. Fixes documentation side of 9213; bugfix on
      0.2.3.18-rc.
    - Resolve warnings from Doxygen.

  o Code simplifications and refactoring:
    - Remove is_internal_IP() function. Resolves ticket 4645.
    - Remove unused function circuit_dump_by_chan from circuitlist.c.
      Closes issue 9107; patch from "marek".
    - Change our use of the ENUM_BF macro to avoid declarations that
      confuse Doxygen.

  o Deprecated versions:
    - Tor 0.2.2.x has reached end-of-life; it has received no patches or
      attention for some while. Directory authorities no longer accept
      descriptors from relays running any version of Tor prior to Tor
      0.2.3.16-alpha. Resolves ticket 11149.

  o Testing:
    - New macros in test.h to simplify writing mock-functions for unit
      tests. Part of ticket 11507. Patch from Dana Koch.
    - Complete tests for the status.c module. Resolves ticket 11507.
      Patch from Dana Koch.

  o Removed code:
    - Remove all code for the long unused v1 directory protocol.
      Resolves ticket 11070.


Changes in version 0.2.5.3-alpha - 2014-03-22
  Tor 0.2.5.3-alpha includes all the fixes from 0.2.4.21. It contains
  two new anti-DoS features for Tor relays, resolves a bug that kept
  SOCKS5 support for IPv6 from working, fixes several annoying usability
  issues for bridge users, and removes more old code for unused
  directory formats.

  The Tor 0.2.5.x release series is now in patch-freeze: no feature
  patches not already written will be considered for inclusion in 0.2.5.x.

  o Major features (relay security, DoS-resistance):
    - When deciding whether we have run out of memory and we need to
      close circuits, also consider memory allocated in buffers for
      streams attached to each circuit.

      This change, which extends an anti-DoS feature introduced in
      0.2.4.13-alpha and improved in 0.2.4.14-alpha, lets Tor exit relays
      better resist more memory-based DoS attacks than before. Since the
      MaxMemInCellQueues option now applies to all queues, it is renamed
      to MaxMemInQueues. This feature fixes bug 10169.
    - Avoid hash-flooding denial-of-service attacks by using the secure
      SipHash-2-4 hash function for our hashtables. Without this
      feature, an attacker could degrade performance of a targeted
      client or server by flooding their data structures with a large
      number of entries to be stored at the same hash table position,
      thereby slowing down the Tor instance. With this feature, hash
      table positions are derived from a randomized cryptographic key,
      and an attacker cannot predict which entries will collide. Closes
      ticket 4900.
    - Decrease the lower limit of MaxMemInQueues to 256 MBytes (but leave
      the default at 8GBytes), to better support Raspberry Pi users. Fixes
      bug 9686; bugfix on 0.2.4.14-alpha.

  o Minor features (bridges, pluggable transports):
    - Bridges now write the SHA1 digest of their identity key
      fingerprint (that is, a hash of a hash of their public key) to
      notice-level logs, and to a new hashed-fingerprint file. This
      information will help bridge operators look up their bridge in
      Globe and similar tools. Resolves ticket 10884.
    - Improve the message that Tor displays when running as a bridge
      using pluggable transports without an Extended ORPort listener.
      Also, log the message in the log file too. Resolves ticket 11043.

  o Minor features (other):
    - Add a new option, PredictedPortsRelevanceTime, to control how long
      after having received a request to connect to a given port Tor
      will try to keep circuits ready in anticipation of future requests
      for that port. Patch from "unixninja92"; implements ticket 9176.
    - Generate a warning if any ports are listed in the SocksPolicy,
      DirPolicy, AuthDirReject, AuthDirInvalid, AuthDirBadDir, or
      AuthDirBadExit options. (These options only support address
      ranges.) Fixes part of ticket 11108.
    - Update geoip and geoip6 to the February 7 2014 Maxmind GeoLite2
      Country database.

  o Minor bugfixes (new since 0.2.5.2-alpha, also in 0.2.4.21):
    - Build without warnings under clang 3.4. (We have some macros that
      define static functions only some of which will get used later in
      the module. Starting with clang 3.4, these give a warning unless the
      unused attribute is set on them.) Resolves ticket 10904.
    - Fix build warnings about missing "a2x" comment when building the
      manpages from scratch on OpenBSD; OpenBSD calls it "a2x.py".
      Fixes bug 10929; bugfix on 0.2.2.9-alpha. Patch from Dana Koch.

  o Minor bugfixes (client):
    - Improve the log message when we can't connect to a hidden service
      because all of the hidden service directory nodes hosting its
      descriptor are excluded. Improves on our fix for bug 10722, which
      was a bugfix on 0.2.0.10-alpha.
    - Raise a control port warning when we fail to connect to all of
      our bridges. Previously, we didn't inform the controller, and
      the bootstrap process would stall. Fixes bug 11069; bugfix on
      0.2.1.2-alpha.
    - Exit immediately when a process-owning controller exits.
      Previously, tor relays would wait for a little while after their
      controller exited, as if they had gotten an INT signal -- but this
      was problematic, since there was no feedback for the user. To do a
      clean shutdown, controllers should send an INT signal and give Tor
      a chance to clean up. Fixes bug 10449; bugfix on 0.2.2.28-beta.
    - Stop attempting to connect to bridges before our pluggable
      transports are configured (harmless but resulted in some erroneous
      log messages). Fixes bug 11156; bugfix on 0.2.3.2-alpha.
    - Fix connections to IPv6 addresses over SOCKS5. Previously, we were
      generating incorrect SOCKS5 responses, and confusing client
      applications. Fixes bug 10987; bugfix on 0.2.4.7-alpha.

  o Minor bugfixes (relays and bridges):
    - Avoid crashing on a malformed resolv.conf file when running a
      relay using Libevent 1. Fixes bug 8788; bugfix on 0.1.1.23.
    - Non-exit relays no longer launch mock DNS requests to check for
      DNS hijacking. This has been unnecessary since 0.2.1.7-alpha, when
      non-exit relays stopped servicing DNS requests. Fixes bug 965;
      bugfix on 0.2.1.7-alpha. Patch from Matt Pagan.
    - Bridges now report complete directory request statistics. Related
      to bug 5824; bugfix on 0.2.2.1-alpha.
    - Bridges now never collect statistics that were designed for
      relays. Fixes bug 5824; bugfix on 0.2.3.8-alpha.
    - Stop giving annoying warning messages when we decide not to launch
      a pluggable transport proxy that we don't need (because there are
      no bridges configured to use it). Resolves ticket 5018; bugfix
      on 0.2.5.2-alpha.
    - Give the correct URL in the warning message when trying to run a
      relay on an ancient version of Windows. Fixes bug 9393.

  o Minor bugfixes (backtrace support):
    - Support automatic backtraces on more platforms by using the
      "-fasynchronous-unwind-tables" compiler option. This option is
      needed for platforms like 32-bit Intel where "-fomit-frame-pointer"
      is on by default and table generation is not. This doesn't yet
      add Windows support; only Linux, OSX, and some BSDs are affected.
      Reported by 'cypherpunks'; fixes bug 11047; bugfix on 0.2.5.2-alpha.
    - Avoid strange behavior if two threads hit failed assertions at the
      same time and both try to log backtraces at once. (Previously, if
      this had happened, both threads would have stored their intermediate
      results in the same buffer, and generated junk outputs.) Reported by
      "cypherpunks". Fixes bug 11048; bugfix on 0.2.5.2-alpha.
    - Fix a compiler warning in format_number_sigsafe(). Bugfix on
      0.2.5.2-alpha; patch from Nick Hopper.

  o Minor bugfixes (unit tests):
    - Fix a small bug in the unit tests that might have made the tests
      call 'chmod' with an uninitialized bitmask. Fixes bug 10928;
      bugfix on 0.2.5.1-alpha. Patch from Dana Koch.

  o Removed code:
    - Remove all remaining code related to version-0 hidden service
      descriptors: they have not been in use since 0.2.2.1-alpha. Fixes
      the rest of bug 10841.

  o Documentation:
    - Document in the manpage that "KBytes" may also be written as
      "kilobytes" or "KB", that "Kbits" may also be written as
      "kilobits", and so forth. Closes ticket 9222.
    - Document that the ClientOnly config option overrides ORPort.
      Our old explanation made ClientOnly sound as though it did
      nothing at all. Resolves bug 9059.
    - Explain that SocksPolicy, DirPolicy, and similar options don't
      take port arguments. Fixes the other part of ticket 11108.
    - Fix a comment about the rend_server_descriptor_t.protocols field
      to more accurately describe its range. Also, make that field
      unsigned, to more accurately reflect its usage. Fixes bug 9099;
      bugfix on 0.2.1.5-alpha.
    - Fix the manpage's description of HiddenServiceAuthorizeClient:
      the maximum client name length is 16, not 19. Fixes bug 11118;
      bugfix on 0.2.1.6-alpha.

  o Code simplifications and refactoring:
    - Get rid of router->address, since in all cases it was just the
      string representation of router->addr. Resolves ticket 5528.

  o Test infrastructure:
    - Update to the latest version of tinytest.
    - Improve the tinytest implementation of string operation tests so
      that comparisons with NULL strings no longer crash the tests; they
      now just fail, normally. Fixes bug 9004; bugfix on 0.2.2.4-alpha.


Changes in version 0.2.4.21 - 2014-02-28
  Tor 0.2.4.21 further improves security against potential adversaries who
  find breaking 1024-bit crypto doable, and backports several stability
  and robustness patches from the 0.2.5 branch.

  o Major features (client security):
    - When we choose a path for a 3-hop circuit, make sure it contains
      at least one relay that supports the NTor circuit extension
      handshake. Otherwise, there is a chance that we're building
      a circuit that's worth attacking by an adversary who finds
      breaking 1024-bit crypto doable, and that chance changes the game
      theory. Implements ticket 9777.

  o Major bugfixes:
    - Do not treat streams that fail with reason
      END_STREAM_REASON_INTERNAL as indicating a definite circuit failure,
      since it could also indicate an ENETUNREACH connection error. Fixes
      part of bug 10777; bugfix on 0.2.4.8-alpha.

  o Code simplification and refactoring:
    - Remove data structures which were introduced to implement the
      CellStatistics option: they are now redundant with the new timestamp
      field in the regular packed_cell_t data structure, which we did
      in 0.2.4.18-rc in order to resolve bug 9093. Resolves ticket 10870.

  o Minor features:
    - Always clear OpenSSL bignums before freeing them -- even bignums
      that don't contain secrets. Resolves ticket 10793. Patch by
      Florent Daigniere.
    - Build without warnings under clang 3.4. (We have some macros that
      define static functions only some of which will get used later in
      the module. Starting with clang 3.4, these give a warning unless the
      unused attribute is set on them.) Resolves ticket 10904.
    - Update geoip and geoip6 files to the February 7 2014 Maxmind
      GeoLite2 Country database.

  o Minor bugfixes:
    - Set the listen() backlog limit to the largest actually supported
      on the system, not to the value in a header file. Fixes bug 9716;
      bugfix on every released Tor.
    - Treat ENETUNREACH, EACCES, and EPERM connection failures at an
      exit node as a NOROUTE error, not an INTERNAL error, since they
      can apparently happen when trying to connect to the wrong sort
      of netblocks. Fixes part of bug 10777; bugfix on 0.1.0.1-rc.
    - Fix build warnings about missing "a2x" comment when building the
      manpages from scratch on OpenBSD; OpenBSD calls it "a2x.py".
      Fixes bug 10929; bugfix on 0.2.2.9-alpha. Patch from Dana Koch.
    - Avoid a segfault on SIGUSR1, where we had freed a connection but did
      not entirely remove it from the connection lists. Fixes bug 9602;
      bugfix on 0.2.4.4-alpha.
    - Fix a segmentation fault in our benchmark code when running with
      Fedora's OpenSSL package, or any other OpenSSL that provides
      ECDH but not P224. Fixes bug 10835; bugfix on 0.2.4.8-alpha.
    - Turn "circuit handshake stats since last time" log messages into a
      heartbeat message. Fixes bug 10485; bugfix on 0.2.4.17-rc.

  o Documentation fixes:
    - Document that all but one DirPort entry must have the NoAdvertise
      flag set. Fixes bug 10470; bugfix on 0.2.3.3-alpha / 0.2.3.16-alpha.


Changes in version 0.2.5.2-alpha - 2014-02-13
  Tor 0.2.5.2-alpha includes all the fixes from 0.2.4.18-rc and 0.2.4.20,
  like the "poor random number generation" fix and the "building too many
  circuits" fix. It also further improves security against potential
  adversaries who find breaking 1024-bit crypto doable, and launches
  pluggable transports on demand (which gets us closer to integrating
  pluggable transport support by default -- not to be confused with Tor
  bundles enabling pluggable transports and bridges by default).

  o Major features (client security):
    - When we choose a path for a 3-hop circuit, make sure it contains
      at least one relay that supports the NTor circuit extension
      handshake. Otherwise, there is a chance that we're building
      a circuit that's worth attacking by an adversary who finds
      breaking 1024-bit crypto doable, and that chance changes the game
      theory. Implements ticket 9777.
    - Clients now look at the "usecreatefast" consensus parameter to
      decide whether to use CREATE_FAST or CREATE cells for the first hop
      of their circuit. This approach can improve security on connections
      where Tor's circuit handshake is stronger than the available TLS
      connection security levels, but the tradeoff is more computational
      load on guard relays. Implements proposal 221. Resolves ticket 9386.

  o Major features (bridges):
    - Don't launch pluggable transport proxies if we don't have any
      bridges configured that would use them. Now we can list many
      pluggable transports, and Tor will dynamically start one when it
      hears a bridge address that needs it. Resolves ticket 5018.
    - The bridge directory authority now assigns status flags (Stable,
      Guard, etc) to bridges based on thresholds calculated over all
      Running bridges. Now bridgedb can finally make use of its features
      to e.g. include at least one Stable bridge in its answers. Fixes
      bug 9859.

  o Major features (other):
    - Extend ORCONN controller event to include an "ID" parameter,
      and add four new controller event types CONN_BW, CIRC_BW,
      CELL_STATS, and TB_EMPTY that show connection and circuit usage.
      The new events are emitted in private Tor networks only, with the
      goal of being able to better track performance and load during
      full-network simulations. Implements proposal 218 and ticket 7359.
    - On some platforms (currently: recent OSX versions, glibc-based
      platforms that support the ELF format, and a few other
      Unix-like operating systems), Tor can now dump stack traces
      when a crash occurs or an assertion fails. By default, traces
      are dumped to stderr (if possible) and to any logs that are
      reporting errors. Implements ticket 9299.

  o Major bugfixes:
    - Avoid a segfault on SIGUSR1, where we had freed a connection but did
      not entirely remove it from the connection lists. Fixes bug 9602;
      bugfix on 0.2.4.4-alpha.
    - Do not treat streams that fail with reason
      END_STREAM_REASON_INTERNAL as indicating a definite circuit failure,
      since it could also indicate an ENETUNREACH connection error. Fixes
      part of bug 10777; bugfix on 0.2.4.8-alpha.

  o Major bugfixes (new since 0.2.5.1-alpha, also in 0.2.4.20):
    - Do not allow OpenSSL engines to replace the PRNG, even when
      HardwareAccel is set. The only default builtin PRNG engine uses
      the Intel RDRAND instruction to replace the entire PRNG, and
      ignores all attempts to seed it with more entropy. That's
      cryptographically stupid: the right response to a new alleged
      entropy source is never to discard all previously used entropy
      sources. Fixes bug 10402; works around behavior introduced in
      OpenSSL 1.0.0. Diagnosis and investigation thanks to "coderman"
      and "rl1987".
    - Fix assertion failure when AutomapHostsOnResolve yields an IPv6
      address. Fixes bug 10465; bugfix on 0.2.4.7-alpha.
    - Avoid launching spurious extra circuits when a stream is pending.
      This fixes a bug where any circuit that _wasn't_ unusable for new
      streams would be treated as if it were, causing extra circuits to
      be launched. Fixes bug 10456; bugfix on 0.2.4.12-alpha.

  o Major bugfixes (new since 0.2.5.1-alpha, also in 0.2.4.18-rc):
    - No longer stop reading or writing on cpuworker connections when
      our rate limiting buckets go empty. Now we should handle circuit
      handshake requests more promptly. Resolves bug 9731.
    - Stop trying to bootstrap all our directory information from
      only our first guard. Discovered while fixing bug 9946; bugfix
      on 0.2.4.8-alpha.

  o Minor features (bridges, pluggable transports):
    - Add threshold cutoffs to the networkstatus document created by
      the Bridge Authority. Fixes bug 1117.
    - On Windows, spawn background processes using the CREATE_NO_WINDOW
      flag. Now Tor Browser Bundle 3.5 with pluggable transports enabled
      doesn't pop up a blank console window. (In Tor Browser Bundle 2.x,
      Vidalia set this option for us.) Implements ticket 10297.

  o Minor features (security):
    - Always clear OpenSSL bignums before freeing them -- even bignums
      that don't contain secrets. Resolves ticket 10793. Patch by
      Florent Daignière.

  o Minor features (config options and command line):
    - Add an --allow-missing-torrc commandline option that tells Tor to
      run even if the configuration file specified by -f is not available.
      Implements ticket 10060.
    - Add support for the TPROXY transparent proxying facility on Linux.
      See documentation for the new TransProxyType option for more
      details. Implementation by "thomo". Closes ticket 10582.

  o Minor features (controller):
    - Add a new "HS_DESC" controller event that reports activities
      related to hidden service descriptors. Resolves ticket 8510.
    - New "DROPGUARDS" controller command to forget all current entry
      guards. Not recommended for ordinary use, since replacing guards
      too frequently makes several attacks easier. Resolves ticket 9934;
      patch from "ra".

  o Minor features (build):
    - Assume that a user using ./configure --host wants to cross-compile,
      and give an error if we cannot find a properly named
      tool-chain. Add a --disable-tool-name-check option to proceed
      nevertheless. Addresses ticket 9869. Patch by Benedikt Gollatz.
    - If we run ./configure and the compiler recognizes -fstack-protector
      but the linker rejects it, warn the user about a potentially missing
      libssp package. Addresses ticket 9948. Patch from Benedikt Gollatz.

  o Minor features (testing):
    - If Python is installed, "make check" now runs extra tests beyond
      the unit test scripts.
    - When bootstrapping a test network, sometimes very few relays get
      the Guard flag. Now a new option "TestingDirAuthVoteGuard" can
      specify a set of relays which should be voted Guard regardless of
      their uptime or bandwidth. Addresses ticket 9206.

  o Minor features (log messages):
    - When ServerTransportPlugin is set on a bridge, Tor can write more
      useful statistics about bridge use in its extrainfo descriptors,
      but only if the Extended ORPort ("ExtORPort") is set too. Add a
      log message to inform the user in this case. Resolves ticket 9651.
    - When receiving a new controller connection, log the origin address.
      Resolves ticket 9698; patch from "sigpipe".
    - When logging OpenSSL engine status at startup, log the status of
      more engines. Fixes ticket 10043; patch from Joshua Datko.
    - Turn "circuit handshake stats since last time" log messages into a
      heartbeat message. Fixes bug 10485; bugfix on 0.2.4.17-rc.

  o Minor features (new since 0.2.5.1-alpha, also in 0.2.4.18-rc):
    - Improve the circuit queue out-of-memory handler. Previously, when
      we ran low on memory, we'd close whichever circuits had the most
      queued cells. Now, we close those that have the *oldest* queued
      cells, on the theory that those are most responsible for us
      running low on memory. Based on analysis from a forthcoming paper
      by Jansen, Tschorsch, Johnson, and Scheuermann. Fixes bug 9093.
    - Generate bootstrapping status update events correctly when fetching
      microdescriptors. Fixes bug 9927.
    - Update to the October 2 2013 Maxmind GeoLite Country database.

  o Minor bugfixes (clients):
    - When closing a channel that has already been open, do not close
      pending circuits that were waiting to connect to the same relay.
      Fixes bug 9880; bugfix on 0.2.5.1-alpha. Thanks to skruffy for
      finding this bug.

  o Minor bugfixes (relays):
    - Treat ENETUNREACH, EACCES, and EPERM connection failures at an
      exit node as a NOROUTE error, not an INTERNAL error, since they
      can apparently happen when trying to connect to the wrong sort
      of netblocks. Fixes part of bug 10777; bugfix on 0.1.0.1-rc.

  o Minor bugfixes (bridges):
    - Fix a bug where the first connection works to a bridge that uses a
      pluggable transport with client-side parameters, but we don't send
      the client-side parameters on subsequent connections. (We don't
      use any pluggable transports with client-side parameters yet,
      but ScrambleSuit will soon become the first one.) Fixes bug 9162;
      bugfix on 0.2.0.3-alpha. Based on a patch from "rl1987".

  o Minor bugfixes (node selection):
    - If ExcludeNodes is set, consider non-excluded hidden service
      directory servers before excluded ones. Do not consider excluded
      hidden service directory servers at all if StrictNodes is
      set. (Previously, we would sometimes decide to connect to those
      servers, and then realize before we initiated a connection that
      we had excluded them.) Fixes bug 10722; bugfix on 0.2.0.10-alpha.
      Reported by "mr-4".
    - If we set the ExitNodes option but it doesn't include any nodes
      that have the Exit flag, we would choose not to bootstrap. Now we
      bootstrap so long as ExitNodes includes nodes which can exit to
      some port. Fixes bug 10543; bugfix on 0.2.4.10-alpha.

  o Minor bugfixes (controller and command-line):
    - If changing a config option via "setconf" fails in a recoverable
      way, we used to nonetheless write our new control ports to the
      file described by the "ControlPortWriteToFile" option. Now we only
      write out that file if we successfully switch to the new config
      option. Fixes bug 5605; bugfix on 0.2.2.26-beta. Patch from "Ryman".
    - When a command-line option such as --version or --help that
      ordinarily implies --hush appears on the command line along with
      --quiet, then actually obey --quiet. Previously, we obeyed --quiet
      only if it appeared later on the command line. Fixes bug 9578;
      bugfix on 0.2.5.1-alpha.

  o Minor bugfixes (code correctness):
    - Previously we used two temporary files when writing descriptors to
      disk; now we only use one. Fixes bug 1376.
    - Remove an erroneous (but impossible and thus harmless) pointer
      comparison that would have allowed compilers to skip a bounds
      check in channeltls.c. Fixes bugs 10313 and 9980; bugfix on
      0.2.0.10-alpha. Noticed by Jared L Wong and David Fifield.
    - Fix an always-true assertion in pluggable transports code so it
      actually checks what it was trying to check. Fixes bug 10046;
      bugfix on 0.2.3.9-alpha. Found by "dcb".

  o Minor bugfixes (protocol correctness):
    - When receiving a VERSIONS cell with an odd number of bytes, close
      the connection immediately since the cell is malformed. Fixes bug
      10365; bugfix on 0.2.0.10-alpha. Spotted by "bobnomnom"; fix by
      "rl1987".

  o Minor bugfixes (build):
    - Restore the ability to compile Tor with V2_HANDSHAKE_SERVER
      turned off (that is, without support for v2 link handshakes). Fixes
      bug 4677; bugfix on 0.2.3.2-alpha. Patch from "piet".
    - Fix compilation warnings and startup issues when running with
      "Sandbox 1" and libseccomp-2.1.0. Fixes bug 10563; bugfix on
      0.2.5.1-alpha.
    - Fix compilation on Solaris 9, which didn't like us having an
      identifier named "sun". Fixes bug 10565; bugfix in 0.2.5.1-alpha.

  o Minor bugfixes (testing):
    - Fix a segmentation fault in our benchmark code when running with
      Fedora's OpenSSL package, or any other OpenSSL that provides
      ECDH but not P224. Fixes bug 10835; bugfix on 0.2.4.8-alpha.

  o Minor bugfixes (log messages):
    - Fix a bug where clients using bridges would report themselves
      as 50% bootstrapped even without a live consensus document.
      Fixes bug 9922; bugfix on 0.2.1.1-alpha.
    - Suppress a warning where, if there's only one directory authority
      in the network, we would complain that votes and signatures cannot
      be uploaded to other directory authorities. Fixes bug 10842;
      bugfix on 0.2.2.26-beta.
    - Report bootstrapping progress correctly when we're downloading
      microdescriptors. We had updated our "do we have enough microdescs
      to begin building circuits?" logic most recently in 0.2.4.10-alpha
      (see bug 5956), but we left the bootstrap status event logic at
      "how far through getting 1/4 of them are we?" Fixes bug 9958;
      bugfix on 0.2.2.36, which is where they diverged (see bug 5343).

  o Minor bugfixes (new since 0.2.5.1-alpha, also in 0.2.4.20):
    - Avoid a crash bug when starting with a corrupted microdescriptor
      cache file. Fixes bug 10406; bugfix on 0.2.2.6-alpha.
    - If we fail to dump a previously cached microdescriptor to disk, avoid
      freeing duplicate data later on. Fixes bug 10423; bugfix on
      0.2.4.13-alpha. Spotted by "bobnomnom".

  o Minor bugfixes on 0.2.4.x (new since 0.2.5.1-alpha, also in 0.2.4.18-rc):
    - Correctly log long IPv6 exit policies, instead of truncating them
      or reporting an error. Fixes bug 9596; bugfix on 0.2.4.7-alpha.
    - Our default TLS ecdhe groups were backwards: we meant to be using
      P224 for relays (for performance win) and P256 for bridges (since
      it is more common in the wild). Instead we had it backwards. After
      reconsideration, we decided that the default should be P256 on all
      hosts, since its security is probably better, and since P224 is
      reportedly used quite little in the wild.  Found by "skruffy" on
      IRC. Fix for bug 9780; bugfix on 0.2.4.8-alpha.
    - Free directory authority certificate download statuses on exit
      rather than leaking them. Fixes bug 9644; bugfix on 0.2.4.13-alpha.

  o Minor bugfixes on 0.2.3.x (new since 0.2.5.1-alpha, also in 0.2.4.18-rc):
    - If the guard we choose first doesn't answer, we would try the
      second guard, but once we connected to the second guard we would
      abandon it and retry the first one, slowing down bootstrapping.
      The fix is to treat all our initially chosen guards as acceptable
      to use. Fixes bug 9946; bugfix on 0.1.1.11-alpha.
    - Fix an assertion failure that would occur when disabling the
      ORPort setting on a running Tor process while accounting was
      enabled. Fixes bug 6979; bugfix on 0.2.2.18-alpha.
    - When examining the list of network interfaces to find our address,
      do not consider non-running or disabled network interfaces. Fixes
      bug 9904; bugfix on 0.2.3.11-alpha. Patch from "hantwister".
    - Avoid an off-by-one error when checking buffer boundaries when
      formatting the exit status of a pluggable transport helper.
      This is probably not an exploitable bug, but better safe than
      sorry. Fixes bug 9928; bugfix on 0.2.3.18-rc. Bug found by
      Pedro Ribeiro.

  o Removed code and features:
    - Clients now reject any directory authority certificates lacking
      a dir-key-crosscert element. These have been included since
      0.2.1.9-alpha, so there's no real reason for them to be optional
      any longer. Completes proposal 157. Resolves ticket 10162.
    - Remove all code that existed to support the v2 directory system,
      since there are no longer any v2 directory authorities. Resolves
      ticket 10758.
    - Remove the HSAuthoritativeDir and AlternateHSAuthority torrc
      options, which were used for designating authorities as "Hidden
      service authorities". There has been no use of hidden service
      authorities since 0.2.2.1-alpha, when we stopped uploading or
      downloading v0 hidden service descriptors. Fixes bug 10881; also
      part of a fix for bug 10841.

  o Code simplification and refactoring:
    - Remove some old fallback code designed to keep Tor clients working
      in a network with only two working relays. Elsewhere in the code we
      have long since stopped supporting such networks, so there wasn't
      much point in keeping it around. Addresses ticket 9926.
    - Reject 0-length EXTEND2 cells more explicitly. Fixes bug 10536;
      bugfix on 0.2.4.8-alpha. Reported by "cypherpunks".
    - Remove data structures which were introduced to implement the
      CellStatistics option: they are now redundant with the addition
      of a timestamp to the regular packed_cell_t data structure, which
      we did in 0.2.4.18-rc in order to resolve ticket 9093. Implements
      ticket 10870.

  o Documentation (man page) fixes:
    - Update manpage to describe some of the files you can expect to
      find in Tor's DataDirectory. Addresses ticket 9839.
    - Document that all but one DirPort entry must have the NoAdvertise
      flag set. Fixes bug 10470; bugfix on 0.2.3.3-alpha / 0.2.3.16-alpha.

  o Documentation fixes (new since 0.2.5.1-alpha, also in 0.2.4.18-rc):
    - Clarify the usage and risks of setting the ContactInfo torrc line
      for your relay or bridge. Resolves ticket 9854.
    - Add anchors to the manpage so we can link to the html version of
      the documentation for specific options. Resolves ticket 9866.
    - Replace remaining references to DirServer in man page and
      log entries. Resolves ticket 10124.

  o Tool changes:
    - Make the "tor-gencert" tool used by directory authority operators
      create 2048-bit signing keys by default (rather than 1024-bit, since
      1024-bit is uncomfortably small these days). Addresses ticket 10324.


Changes in version 0.2.4.20 - 2013-12-22
  Tor 0.2.4.20 fixes potentially poor random number generation for users
  who 1) use OpenSSL 1.0.0 or later, 2) set "HardwareAccel 1" in their
  torrc file, 3) have "Sandy Bridge" or "Ivy Bridge" Intel processors,
  and 4) have no state file in their DataDirectory (as would happen on
  first start). Users who generated relay or hidden service identity
  keys in such a situation should discard them and generate new ones.

  This release also fixes a logic error that caused Tor clients to build
  many more preemptive circuits than they actually need.

  o Major bugfixes:
    - Do not allow OpenSSL engines to replace the PRNG, even when
      HardwareAccel is set. The only default builtin PRNG engine uses
      the Intel RDRAND instruction to replace the entire PRNG, and
      ignores all attempts to seed it with more entropy. That's
      cryptographically stupid: the right response to a new alleged
      entropy source is never to discard all previously used entropy
      sources. Fixes bug 10402; works around behavior introduced in
      OpenSSL 1.0.0. Diagnosis and investigation thanks to "coderman"
      and "rl1987".
    - Fix assertion failure when AutomapHostsOnResolve yields an IPv6
      address. Fixes bug 10465; bugfix on 0.2.4.7-alpha.
    - Avoid launching spurious extra circuits when a stream is pending.
      This fixes a bug where any circuit that _wasn't_ unusable for new
      streams would be treated as if it were, causing extra circuits to
      be launched. Fixes bug 10456; bugfix on 0.2.4.12-alpha.

  o Minor bugfixes:
    - Avoid a crash bug when starting with a corrupted microdescriptor
      cache file. Fixes bug 10406; bugfix on 0.2.2.6-alpha.
    - If we fail to dump a previously cached microdescriptor to disk, avoid
      freeing duplicate data later on. Fixes bug 10423; bugfix on
      0.2.4.13-alpha. Spotted by "bobnomnom".


Changes in version 0.2.4.19 - 2013-12-11
  The Tor 0.2.4 release series is dedicated to the memory of Aaron Swartz
  (1986-2013). Aaron worked on diverse projects including helping to guide
  Creative Commons, playing a key role in stopping SOPA/PIPA, bringing
  transparency to the U.S government's PACER documents, and contributing
  design and development for Tor and Tor2Web. Aaron was one of the latest
  martyrs in our collective fight for civil liberties and human rights,
  and his death is all the more painful because he was one of us.

  Tor 0.2.4.19, the first stable release in the 0.2.4 branch, features
  a new circuit handshake and link encryption that use ECC to provide
  better security and efficiency; makes relays better manage circuit
  creation requests; uses "directory guards" to reduce client enumeration
  risks; makes bridges collect and report statistics about the pluggable
  transports they support; cleans up and improves our geoip database;
  gets much closer to IPv6 support for clients, bridges, and relays; makes
  directory authorities use measured bandwidths rather than advertised
  ones when computing flags and thresholds; disables client-side DNS
  caching to reduce tracking risks; and fixes a big bug in bridge
  reachability testing. This release introduces two new design
  abstractions in the code: a new "channel" abstraction between circuits
  and or_connections to allow for implementing alternate relay-to-relay
  transports, and a new "circuitmux" abstraction storing the queue of
  circuits for a channel. The release also includes many stability,
  security, and privacy fixes.


Changes in version 0.2.4.18-rc - 2013-11-16
  Tor 0.2.4.18-rc is the fourth release candidate for the Tor 0.2.4.x
  series. It takes a variety of fixes from the 0.2.5.x branch to improve
  stability, performance, and better handling of edge cases.

  o Major features:
    - Re-enable TLS 1.1 and 1.2 when built with OpenSSL 1.0.1e or later.
      Resolves ticket 6055. (OpenSSL before 1.0.1 didn't have TLS 1.1 or
      1.2, and OpenSSL from 1.0.1 through 1.0.1d had bugs that prevented
      renegotiation from working with TLS 1.1 or 1.2, so we had disabled
      them to solve bug 6033.)

  o Major bugfixes:
    - No longer stop reading or writing on cpuworker connections when
      our rate limiting buckets go empty. Now we should handle circuit
      handshake requests more promptly. Resolves bug 9731.
    - If we are unable to save a microdescriptor to the journal, do not
      drop it from memory and then reattempt downloading it. Fixes bug
      9645; bugfix on 0.2.2.6-alpha.
    - Stop trying to bootstrap all our directory information from
      only our first guard. Discovered while fixing bug 9946; bugfix
      on 0.2.4.8-alpha.
    - The new channel code sometimes lost track of in-progress circuits,
      causing long-running clients to stop building new circuits. The
      fix is to always call circuit_n_chan_done(chan, 0) from
      channel_closed(). Fixes bug 9776; bugfix on 0.2.4.17-rc.

  o Minor bugfixes (on 0.2.4.x):
    - Correctly log long IPv6 exit policies, instead of truncating them
      or reporting an error. Fixes bug 9596; bugfix on 0.2.4.7-alpha.
    - Our default TLS ecdhe groups were backwards: we meant to be using
      P224 for relays (for performance win) and P256 for bridges (since
      it is more common in the wild). Instead we had it backwards. After
      reconsideration, we decided that the default should be P256 on all
      hosts, since its security is probably better, and since P224 is
      reportedly used quite little in the wild.  Found by "skruffy" on
      IRC. Fix for bug 9780; bugfix on 0.2.4.8-alpha.
    - Free directory authority certificate download statuses on exit
      rather than leaking them. Fixes bug 9644; bugfix on 0.2.4.13-alpha.

  o Minor bugfixes (on 0.2.3.x and earlier):
    - If the guard we choose first doesn't answer, we would try the
      second guard, but once we connected to the second guard we would
      abandon it and retry the first one, slowing down bootstrapping.
      The fix is to treat all our initially chosen guards as acceptable
      to use. Fixes bug 9946; bugfix on 0.1.1.11-alpha.
    - Fix an assertion failure that would occur when disabling the
      ORPort setting on a running Tor process while accounting was
      enabled. Fixes bug 6979; bugfix on 0.2.2.18-alpha.
    - When examining the list of network interfaces to find our address,
      do not consider non-running or disabled network interfaces. Fixes
      bug 9904; bugfix on 0.2.3.11-alpha. Patch from "hantwister".
    - Avoid an off-by-one error when checking buffer boundaries when
      formatting the exit status of a pluggable transport helper.
      This is probably not an exploitable bug, but better safe than
      sorry. Fixes bug 9928; bugfix on 0.2.3.18-rc. Bug found by
      Pedro Ribeiro.

  o Minor features (protecting client timestamps):
    - Clients no longer send timestamps in their NETINFO cells. These were
      not used for anything, and they provided one small way for clients
      to be distinguished from each other as they moved from network to
      network or behind NAT. Implements part of proposal 222.
    - Clients now round timestamps in INTRODUCE cells down to the nearest
      10 minutes. If a new Support022HiddenServices option is set to 0, or
      if it's set to "auto" and the feature is disabled in the consensus,
      the timestamp is sent as 0 instead. Implements part of proposal 222.
    - Stop sending timestamps in AUTHENTICATE cells. This is not such
      a big deal from a security point of view, but it achieves no actual
      good purpose, and isn't needed. Implements part of proposal 222.
    - Reduce down accuracy of timestamps in hidden service descriptors.
      Implements part of proposal 222.

  o Minor features (other):
    - Improve the circuit queue out-of-memory handler. Previously, when
      we ran low on memory, we'd close whichever circuits had the most
      queued cells. Now, we close those that have the *oldest* queued
      cells, on the theory that those are most responsible for us
      running low on memory. Based on analysis from a forthcoming paper
      by Jansen, Tschorsch, Johnson, and Scheuermann. Fixes bug 9093.
    - Generate bootstrapping status update events correctly when fetching
      microdescriptors. Fixes bug 9927.
    - Update to the October 2 2013 Maxmind GeoLite Country database.

  o Documentation fixes:
    - Clarify the usage and risks of setting the ContactInfo torrc line
      for your relay or bridge. Resolves ticket 9854.
    - Add anchors to the manpage so we can link to the html version of
      the documentation for specific options. Resolves ticket 9866.
    - Replace remaining references to DirServer in man page and
      log entries. Resolves ticket 10124.


Changes in version 0.2.5.1-alpha - 2013-10-02
  Tor 0.2.5.1-alpha introduces experimental support for syscall sandboxing
  on Linux, allows bridges that offer pluggable transports to report usage
  statistics, fixes many issues to make testing easier, and provides
  a pile of minor features and bugfixes that have been waiting for a
  release of the new branch.

  This is the first alpha release in a new series, so expect there to
  be bugs. Users who would rather test out a more stable branch should
  stay with 0.2.4.x for now.

  o Major features (security):
    - Use the seccomp2 syscall filtering facility on Linux to limit
      which system calls Tor can invoke. This is an experimental,
      Linux-only feature to provide defense-in-depth against unknown
      attacks. To try turning it on, set "Sandbox 1" in your torrc
      file. Please be ready to report bugs. We hope to add support
      for better sandboxing in the future, including more fine-grained
      filters, better division of responsibility, and support for more
      platforms. This work has been done by Cristian-Matei Toader for
      Google Summer of Code.
    - Re-enable TLS 1.1 and 1.2 when built with OpenSSL 1.0.1e or later.
      Resolves ticket 6055. (OpenSSL before 1.0.1 didn't have TLS 1.1 or
      1.2, and OpenSSL from 1.0.1 through 1.0.1d had bugs that prevented
      renegotiation from working with TLS 1.1 or 1.2, so we had disabled
      them to solve bug 6033.)

  o Major features (other):
    - Add support for passing arguments to managed pluggable transport
      proxies. Implements ticket 3594.
    - Bridges now track GeoIP information and the number of their users
      even when pluggable transports are in use, and report usage
      statistics in their extra-info descriptors. Resolves tickets 4773
      and 5040.
    - Make testing Tor networks bootstrap better: lower directory fetch
      retry schedules and maximum interval without directory requests,
      and raise maximum download tries. Implements ticket 6752.
    - Add make target 'test-network' to run tests on a Chutney network.
      Implements ticket 8530.
    - The ntor handshake is now on-by-default, no matter what the
      directory authorities recommend. Implements ticket 8561.

  o Major bugfixes:
    - Instead of writing destroy cells directly to outgoing connection
      buffers, queue them and intersperse them with other outgoing cells.
      This can prevent a set of resource starvation conditions where too
      many pending destroy cells prevent data cells from actually getting
      delivered. Reported by "oftc_must_be_destroyed". Fixes bug 7912;
      bugfix on 0.2.0.1-alpha.
    - If we are unable to save a microdescriptor to the journal, do not
      drop it from memory and then reattempt downloading it. Fixes bug
      9645; bugfix on 0.2.2.6-alpha.
    - The new channel code sometimes lost track of in-progress circuits,
      causing long-running clients to stop building new circuits. The
      fix is to always call circuit_n_chan_done(chan, 0) from
      channel_closed(). Fixes bug 9776; bugfix on 0.2.4.17-rc.

  o Build features:
    - Tor now builds each source file in two modes: a mode that avoids
      exposing identifiers needlessly, and another mode that exposes
      more identifiers for testing. This lets the compiler do better at
      optimizing the production code, while enabling us to take more
      radical measures to let the unit tests test things.
    - The production builds no longer include functions used only in
      the unit tests; all functions exposed from a module only for
      unit-testing are now static in production builds.
    - Add an --enable-coverage configuration option to make the unit
      tests (and a new src/or/tor-cov target) to build with gcov test
      coverage support.

  o Testing:
    - We now have rudimentary function mocking support that our unit
      tests can use to test functions in isolation. Function mocking
      lets the tests temporarily replace a function's dependencies with
      stub functions, so that the tests can check the function without
      invoking the other functions it calls.
    - Add more unit tests for the ->circuit map, and
      the destroy-cell-tracking code to fix bug 7912.
    - Unit tests for failing cases of the TAP onion handshake.
    - More unit tests for address-manipulation functions.

  o Minor features (protecting client timestamps):
    - Clients no longer send timestamps in their NETINFO cells. These were
      not used for anything, and they provided one small way for clients
      to be distinguished from each other as they moved from network to
      network or behind NAT. Implements part of proposal 222.
    - Clients now round timestamps in INTRODUCE cells down to the nearest
      10 minutes. If a new Support022HiddenServices option is set to 0, or
      if it's set to "auto" and the feature is disabled in the consensus,
      the timestamp is sent as 0 instead. Implements part of proposal 222.
    - Stop sending timestamps in AUTHENTICATE cells. This is not such
      a big deal from a security point of view, but it achieves no actual
      good purpose, and isn't needed. Implements part of proposal 222.
    - Reduce down accuracy of timestamps in hidden service descriptors.
      Implements part of proposal 222.

  o Minor features (config options):
    - Config (torrc) lines now handle fingerprints which are missing
      their initial '$'. Resolves ticket 4341; improvement over 0.0.9pre5.
    - Support a --dump-config option to print some or all of the
      configured options. Mainly useful for debugging the command-line
      option parsing code. Helps resolve ticket 4647.
    - Raise awareness of safer logging: notify user of potentially
      unsafe config options, like logging more verbosely than severity
      "notice" or setting SafeLogging to 0. Resolves ticket 5584.
    - Add a new configuration option TestingV3AuthVotingStartOffset
      that bootstraps a network faster by changing the timing for
      consensus votes. Addresses ticket 8532.
    - Add a new torrc option "ServerTransportOptions" that allows
      bridge operators to pass configuration parameters to their
      pluggable transports. Resolves ticket 8929.
    - The config (torrc) file now accepts bandwidth and space limits in
      bits as well as bytes. (Anywhere that you can say "2 Kilobytes",
      you can now say "16 kilobits", and so on.) Resolves ticket 9214.
      Patch by CharlieB.

  o Minor features (build):
    - Add support for `--library-versions` flag. Implements ticket 6384.
    - Return the "unexpected sendme" warnings to a warn severity, but make
      them rate limited, to help diagnose ticket 8093.
    - Detect a missing asciidoc, and warn the user about it, during
      configure rather than at build time. Fixes issue 6506. Patch from
      Arlo Breault.

  o Minor features (other):
    - Use the SOCK_NONBLOCK socket type, if supported, to open nonblocking
      sockets in a single system call. Implements ticket 5129.
    - Log current accounting state (bytes sent and received + remaining
      time for the current accounting period) in the relay's heartbeat
      message. Implements ticket 5526; patch from Peter Retzlaff.
    - Implement the TRANSPORT_LAUNCHED control port event that
      notifies controllers about new launched pluggable
      transports. Resolves ticket 5609.
    - If we're using the pure-C 32-bit curve25519_donna implementation
      of curve25519, build it with the -fomit-frame-pointer option to
      make it go faster on register-starved hosts. This improves our
      handshake performance by about 6% on i386 hosts without nacl.
      Closes ticket 8109.
    - Update to the September 4 2013 Maxmind GeoLite Country database.

  o Minor bugfixes:
    - Set the listen() backlog limit to the largest actually supported
      on the system, not to the value in a header file. Fixes bug 9716;
      bugfix on every released Tor.
    - No longer accept malformed http headers when parsing urls from
      headers. Now we reply with Bad Request ("400"). Fixes bug 2767;
      bugfix on 0.0.6pre1.
    - In munge_extrainfo_into_routerinfo(), check the return value of
      memchr(). This would have been a serious issue if we ever passed
      it a non-extrainfo. Fixes bug 8791; bugfix on 0.2.0.6-alpha. Patch
      from Arlo Breault.
    - On the chance that somebody manages to build Tor on a
      platform where time_t is unsigned, correct the way that
      microdesc_add_to_cache() handles negative time arguments.
      Fixes bug 8042; bugfix on 0.2.3.1-alpha.
    - Reject relative control socket paths and emit a warning. Previously,
      single-component control socket paths would be rejected, but Tor
      would not log why it could not validate the config. Fixes bug 9258;
      bugfix on 0.2.3.16-alpha.

  o Minor bugfixes (command line):
    - Use a single command-line parser for parsing torrc options on the
      command line and for finding special command-line options to avoid
      inconsistent behavior for torrc option arguments that have the same
      names as command-line options. Fixes bugs 4647 and 9578; bugfix on
      0.0.9pre5.
    - No longer allow 'tor --hash-password' with no arguments. Fixes bug
      9573; bugfix on 0.0.9pre5.

  o Minor fixes (build, auxiliary programs):
    - Stop preprocessing the "torify" script with autoconf, since
      it no longer refers to LOCALSTATEDIR. Fixes bug 5505; patch
      from Guilhem.
    - The tor-fw-helper program now follows the standard convention and
      exits with status code "0" on success. Fixes bug 9030; bugfix on
      0.2.3.1-alpha. Patch by Arlo Breault.
    - Corrected ./configure advice for what openssl dev package you should
      install on Debian. Fixes bug 9207; bugfix on 0.2.0.1-alpha.

  o Minor code improvements:
    - Remove constants and tests for PKCS1 padding; it's insecure and
      shouldn't be used for anything new. Fixes bug 8792; patch
      from Arlo Breault.
    - Remove instances of strcpy() from the unit tests. They weren't
      hurting anything, since they were only in the unit tests, but it's
      embarrassing to have strcpy() in the code at all, and some analysis
      tools don't like it. Fixes bug 8790; bugfix on 0.2.3.6-alpha and
      0.2.3.8-alpha. Patch from Arlo Breault.

  o Removed features:
    - Remove migration code from when we renamed the "cached-routers"
      file to "cached-descriptors" back in 0.2.0.8-alpha. This
      incidentally resolves ticket 6502 by cleaning up the related code
      a bit. Patch from Akshay Hebbar.

  o Code simplification and refactoring:
    - Extract the common duplicated code for creating a subdirectory
      of the data directory and writing to a file in it. Fixes ticket
      4282; patch from Peter Retzlaff.
    - Since OpenSSL 0.9.7, the i2d_*() functions support allocating output
      buffer. Avoid calling twice: i2d_RSAPublicKey(), i2d_DHparams(),
      i2d_X509(), and i2d_PublicKey(). Resolves ticket 5170.
    - Add a set of accessor functions for the circuit timeout data
      structure. Fixes ticket 6153; patch from "piet".
    - Clean up exit paths from connection_listener_new(). Closes ticket
      8789. Patch from Arlo Breault.
    - Since we rely on OpenSSL 0.9.8 now, we can use EVP_PKEY_cmp()
      and drop our own custom pkey_eq() implementation. Fixes bug 9043.
    - Use a doubly-linked list to implement the global circuit list.
      Resolves ticket 9108. Patch from Marek Majkowski.
    - Remove contrib/id_to_fp.c since it wasn't used anywhere.


Changes in version 0.2.4.17-rc - 2013-09-05
  Tor 0.2.4.17-rc is the third release candidate for the Tor 0.2.4.x
  series. It adds an emergency step to help us tolerate the massive
  influx of users: 0.2.4 clients using the new (faster and safer) "NTor"
  circuit-level handshakes now effectively jump the queue compared to
  the 0.2.3 clients using "TAP" handshakes. This release also fixes a
  big bug hindering bridge reachability tests.

  o Major features:
    - Relays now process the new "NTor" circuit-level handshake requests
      with higher priority than the old "TAP" circuit-level handshake
      requests. We still process some TAP requests to not totally starve
      0.2.3 clients when NTor becomes popular. A new consensus parameter
      "NumNTorsPerTAP" lets us tune the balance later if we need to.
      Implements ticket 9574.

  o Major bugfixes:
    - If the circuit build timeout logic is disabled (via the consensus,
      or because we are an authority), then don't build testing circuits.
      Fixes bug 9657; bugfix on 0.2.2.14-alpha.
    - Bridges now send AUTH_CHALLENGE cells during their v3 handshakes;
      previously they did not, which prevented them from receiving
      successful connections from relays for self-test or bandwidth
      testing. Also, when a relay is extending a circuit to a bridge,
      it needs to send a NETINFO cell, even when the bridge hasn't sent
      an AUTH_CHALLENGE cell. Fixes bug 9546; bugfix on 0.2.3.6-alpha.
    - If the time to download the next old-style networkstatus is in
      the future, do not decline to consider whether to download the
      next microdescriptor networkstatus. Fixes bug 9564; bugfix on
      0.2.3.14-alpha.

  o Minor bugfixes:
    - Avoid double-closing the listener socket in our socketpair()
      replacement (used on Windows) in the case where the addresses on
      our opened sockets don't match what we expected. Fixes bug 9400;
      bugfix on 0.0.2pre7. Found by Coverity.

  o Minor fixes (config options):
    - Avoid overflows when the user sets MaxCircuitDirtiness to a
      ridiculously high value, by imposing a (ridiculously high) 30-day
      maximum on MaxCircuitDirtiness.
    - Fix the documentation of HeartbeatPeriod to say that the heartbeat
      message is logged at notice, not at info.
    - Warn and fail if a server is configured not to advertise any
      ORPorts at all. (We need *something* to put in our descriptor,
      or we just won't work.)

  o Minor features:
    - Track how many "TAP" and "NTor" circuit handshake requests we get,
      and how many we complete, and log it every hour to help relay
      operators follow trends in network load. Addresses ticket 9658.
    - Update to the August 7 2013 Maxmind GeoLite Country database.


Changes in version 0.2.4.16-rc - 2013-08-10
  Tor 0.2.4.16-rc is the second release candidate for the Tor 0.2.4.x
  series. It fixes several crash bugs in the 0.2.4 branch.

  o Major bugfixes:
    - Fix a bug in the voting algorithm that could yield incorrect results
      when a non-naming authority declared too many flags. Fixes bug 9200;
      bugfix on 0.2.0.3-alpha.
    - Fix an uninitialized read that could in some cases lead to a remote
      crash while parsing INTRODUCE2 cells. Bugfix on 0.2.4.1-alpha.
      Anybody running a hidden service on the experimental 0.2.4.x
      branch should upgrade. (This is, so far as we know, unrelated to
      the recent news.)
    - Avoid an assertion failure when processing DNS replies without the
      answer types we expected. Fixes bug 9337; bugfix on 0.2.4.7-alpha.
    - Avoid a crash when using --hash-password. Fixes bug 9295; bugfix on
      0.2.4.15-rc. Found by stem integration tests.

  o Minor bugfixes:
    - Fix an invalid memory read that occurred when a pluggable
      transport proxy failed its configuration protocol.
      Fixes bug 9288; bugfix on 0.2.4.1-alpha.
    - When evaluating whether to use a connection that we haven't
      decided is canonical using a recent link protocol version,
      decide that it's canonical only if it used address _does_
      match the desired address. Fixes bug 9309; bugfix on
      0.2.4.4-alpha. Reported by skruffy.
    - Make the default behavior of NumDirectoryGuards be to track
      NumEntryGuards. Now a user who changes only NumEntryGuards will get
      the behavior she expects. Fixes bug 9354; bugfix on 0.2.4.8-alpha.
    - Fix a spurious compilation warning with some older versions of
      GCC on FreeBSD. Fixes bug 9254; bugfix on 0.2.4.14-alpha.

  o Minor features:
    - Update to the July 3 2013 Maxmind GeoLite Country database.


Changes in version 0.2.4.15-rc - 2013-07-01
  Tor 0.2.4.15-rc is the first release candidate for the Tor 0.2.4.x
  series. It fixes a few smaller bugs, but generally appears stable.
  Please test it and let us know whether it is!

  o Major bugfixes:
    - When receiving a new configuration file via the control port's
      LOADCONF command, do not treat the defaults file as absent.
      Fixes bug 9122; bugfix on 0.2.3.9-alpha.

  o Minor features:
    - Issue a warning when running with the bufferevents backend enabled.
      It's still not stable, and people should know that they're likely
      to hit unexpected problems. Closes ticket 9147.


Changes in version 0.2.4.14-alpha - 2013-06-18
  Tor 0.2.4.14-alpha fixes a pair of client guard enumeration problems
  present in 0.2.4.13-alpha.

  o Major bugfixes:
    - When we have too much memory queued in circuits (according to a new
      MaxMemInCellQueues option), close the circuits consuming the most
      memory. This prevents us from running out of memory as a relay if
      circuits fill up faster than they can be drained. Fixes bug 9063;
      bugfix on the 54th commit of Tor. This bug is a further fix beyond
      bug 6252, whose fix was merged into 0.2.3.21-rc.

      This change also fixes an earlier approach taken in 0.2.4.13-alpha,
      where we tried to solve this issue simply by imposing an upper limit
      on the number of queued cells for a single circuit. That approach
      proved to be problematic, since there are ways to provoke clients to
      send a number of cells in excess of any such reasonable limit. Fixes
      bug 9072; bugfix on 0.2.4.13-alpha.

    - Limit hidden service descriptors to at most ten introduction
      points, to slow one kind of guard enumeration. Fixes bug 9002;
      bugfix on 0.1.1.11-alpha.


Changes in version 0.2.4.13-alpha - 2013-06-14
  Tor 0.2.4.13-alpha fixes a variety of potential remote crash
  vulnerabilities, makes socks5 username/password circuit isolation
  actually actually work (this time for sure!), and cleans up a bunch
  of other issues in preparation for a release candidate.

  o Major bugfixes (robustness):
    - Close any circuit that has too many cells queued on it. Fixes
      bug 9063; bugfix on the 54th commit of Tor. This bug is a further
      fix beyond bug 6252, whose fix was merged into 0.2.3.21-rc.
    - Prevent the get_freelists() function from running off the end of
      the list of freelists if it somehow gets an unrecognized
      allocation. Fixes bug 8844; bugfix on 0.2.0.16-alpha. Reported by
      eugenis.
    - Avoid an assertion failure on OpenBSD (and perhaps other BSDs)
      when an exit connection with optimistic data succeeds immediately
      rather than returning EINPROGRESS. Fixes bug 9017; bugfix on
      0.2.3.1-alpha.
    - Fix a directory authority crash bug when building a consensus
      using an older consensus as its basis. Fixes bug 8833. Bugfix
      on 0.2.4.12-alpha.

  o Major bugfixes:
    - Avoid a memory leak where we would leak a consensus body when we
      find that a consensus which we couldn't previously verify due to
      missing certificates is now verifiable. Fixes bug 8719; bugfix
      on 0.2.0.10-alpha.
    - We used to always request authority certificates by identity digest,
      meaning we'd get the newest one even when we wanted one with a
      different signing key. Then we would complain about being given
      a certificate we already had, and never get the one we really
      wanted. Now we use the "fp-sk/" resource as well as the "fp/"
      resource to request the one we want. Fixes bug 5595; bugfix on
      0.2.0.8-alpha.
    - Follow the socks5 protocol when offering username/password
      authentication. The fix for bug 8117 exposed this bug, and it
      turns out real-world applications like Pidgin do care. Bugfix on
      0.2.3.2-alpha; fixes bug 8879.
    - Prevent failures on Windows Vista and later when rebuilding the
      microdescriptor cache. Diagnosed by Robert Ransom. Fixes bug 8822;
      bugfix on 0.2.4.12-alpha.

  o Minor bugfixes:
    - Fix an impossible buffer overrun in the AES unit tests. Fixes
      bug 8845; bugfix on 0.2.0.7-alpha. Found by eugenis.
    - If for some reason we fail to write a microdescriptor while
      rebuilding the cache, do not let the annotations from that
      microdescriptor linger in the cache file, and do not let the
      microdescriptor stay recorded as present in its old location.
      Fixes bug 9047; bugfix on 0.2.2.6-alpha.
    - Fix a memory leak that would occur whenever a configuration
      option changed. Fixes bug 8718; bugfix on 0.2.3.3-alpha.
    - Paste the description for PathBias parameters from the man
      page into or.h, so the code documents them too. Fixes bug 7982;
      bugfix on 0.2.3.17-beta and 0.2.4.8-alpha.
    - Relays now treat a changed IPv6 ORPort as sufficient reason to
      publish an updated descriptor. Fixes bug 6026; bugfix on
      0.2.4.1-alpha.
    - When launching a resolve request on behalf of an AF_UNIX control
      socket, omit the address field of the new entry connection, used in
      subsequent controller events, rather than letting tor_dup_addr()
      set it to "". Fixes bug 8639; bugfix on
      0.2.4.12-alpha.

  o Minor bugfixes (log messages):
    - Fix a scaling issue in the path bias accounting code that
      resulted in "Bug:" log messages from either
      pathbias_scale_close_rates() or pathbias_count_build_success().
      This represents a bugfix on a previous bugfix: the original fix
      attempted in 0.2.4.10-alpha was incomplete. Fixes bug 8235; bugfix
      on 0.2.4.1-alpha.
    - Give a less useless error message when the user asks for an IPv4
      address on an IPv6-only port, or vice versa. Fixes bug 8846; bugfix
      on 0.2.4.7-alpha.

  o Minor features:
    - Downgrade "unexpected SENDME" warnings to protocol-warn for 0.2.4.x,
      to tolerate bug 8093 for now.
    - Add an "ignoring-advertised-bws" boolean to the flag-threshold lines
      in directory authority votes to describe whether they have enough
      measured bandwidths to ignore advertised (relay descriptor)
      bandwidth claims. Resolves ticket 8711.
    - Update to the June 5 2013 Maxmind GeoLite Country database.

  o Removed documentation:
    - Remove some of the older contents of doc/ as obsolete; move others
      to torspec.git. Fixes bug 8965.

  o Code simplification and refactoring:
    - Avoid using character buffers when constructing most directory
      objects: this approach was unwieldy and error-prone. Instead,
      build smartlists of strings, and concatenate them when done.


Changes in version 0.2.4.12-alpha - 2013-04-18
  Tor 0.2.4.12-alpha moves Tor forward on several fronts: it starts the
  process for lengthening the guard rotation period, makes directory
  authority opinions in the consensus a bit less gameable, makes socks5
  username/password circuit isolation actually work, and fixes a wide
  variety of other issues.

  o Major features:
    - Raise the default time that a client keeps an entry guard from
      "1-2 months" to "2-3 months", as suggested by Tariq Elahi's WPES
      2012 paper. (We would make it even longer, but we need better client
      load balancing first.) Also, make the guard lifetime controllable
      via a new GuardLifetime torrc option and a GuardLifetime consensus
      parameter. Start of a fix for bug 8240; bugfix on 0.1.1.11-alpha.
    - Directory authorities now prefer using measured bandwidths to
      advertised ones when computing flags and thresholds. Resolves
      ticket 8273.
    - Directory authorities that have more than a threshold number
      of relays with measured bandwidths now treat relays with unmeasured
      bandwidths as having bandwidth 0. Resolves ticket 8435.

  o Major bugfixes (assert / resource use):
    - Avoid a bug where our response to TLS renegotiation under certain
      network conditions could lead to a busy-loop, with 100% CPU
      consumption. Fixes bug 5650; bugfix on 0.2.0.16-alpha.
    - Avoid an assertion when we discover that we'd like to write a cell
      onto a closing connection: just discard the cell. Fixes another
      case of bug 7350; bugfix on 0.2.4.4-alpha.

  o Major bugfixes (client-side privacy):
    - When we mark a circuit as unusable for new circuits, have it
      continue to be unusable for new circuits even if MaxCircuitDirtiness
      is increased too much at the wrong time, or the system clock jumps
      backwards. Fixes bug 6174; bugfix on 0.0.2pre26.
    - If ClientDNSRejectInternalAddresses ("do not believe DNS queries
      which have resolved to internal addresses") is set, apply that
      rule to IPv6 as well. Fixes bug 8475; bugfix on 0.2.0.7-alpha.
    - When an exit relay rejects a stream with reason "exit policy", but
      we only know an exit policy summary (e.g. from the microdesc
      consensus) for it, do not mark the relay as useless for all exiting.
      Instead, mark just the circuit as unsuitable for that particular
      address. Fixes part of bug 7582; bugfix on 0.2.3.2-alpha.
    - Allow applications to get proper stream isolation with
      IsolateSOCKSAuth. Many SOCKS5 clients that want to offer
      username/password authentication also offer "no authentication". Tor
      had previously preferred "no authentication", so the applications
      never actually sent Tor their auth details. Now Tor selects
      username/password authentication if it's offered. You can disable
      this behavior on a per-SOCKSPort basis via PreferSOCKSNoAuth. Fixes
      bug 8117; bugfix on 0.2.3.3-alpha.

  o Major bugfixes (other):
    - When unable to find any working directory nodes to use as a
      directory guard, give up rather than adding the same non-working
      nodes to the directory guard list over and over. Fixes bug 8231;
      bugfix on 0.2.4.8-alpha.

  o Minor features:
    - Reject as invalid most directory objects containing a NUL.
      Belt-and-suspender fix for bug 8037.
    - In our testsuite, create temporary directories with a bit more
      entropy in their name to make name collisions less likely. Fixes
      bug 8638.
    - Add CACHED keyword to ADDRMAP events in the control protocol
      to indicate whether a DNS result will be cached or not. Resolves
      ticket 8596.
    - Update to the April 3 2013 Maxmind GeoLite Country database.

  o Minor features (build):
    - Detect and reject attempts to build Tor with threading support
      when OpenSSL has been compiled without threading support.
      Fixes bug 6673.
    - Clarify that when autoconf is checking for nacl, it is checking
      specifically for nacl with a fast curve25519 implementation.
      Fixes bug 8014.
    - Warn if building on a platform with an unsigned time_t: there
      are too many places where Tor currently assumes that time_t can
      hold negative values. We'd like to fix them all, but probably
      some will remain.

  o Minor bugfixes (build):
    - Fix some bugs in tor-fw-helper-natpmp when trying to build and
      run it on Windows. More bugs likely remain. Patch from Gisle Vanem.
      Fixes bug 7280; bugfix on 0.2.3.1-alpha.
    - Add the old src/or/micro-revision.i filename to CLEANFILES.
      On the off chance that somebody has one, it will go away as soon
      as they run "make clean". Fix for bug 7143; bugfix on 0.2.4.1-alpha.
    - Build Tor correctly on 32-bit platforms where the compiler can build
      but not run code using the "uint128_t" construction. Fixes bug 8587;
      bugfix on 0.2.4.8-alpha.
    - Fix compilation warning with some versions of clang that would
      prefer the -Wswitch-enum compiler flag to warn about switch
      statements with missing enum values, even if those switch
      statements have a "default:" statement. Fixes bug 8598; bugfix
      on 0.2.4.10-alpha.

  o Minor bugfixes (protocol):
    - Fix the handling of a TRUNCATE cell when it arrives while the
      circuit extension is in progress. Fixes bug 7947; bugfix on 0.0.7.1.
    - Fix a misframing issue when reading the version numbers in a
      VERSIONS cell. Previously we would recognize [00 01 00 02] as
      'version 1, version 2, and version 0x100', when it should have
      only included versions 1 and 2. Fixes bug 8059; bugfix on
      0.2.0.10-alpha. Reported pseudonymously.
    - Make the format and order of STREAM events for DNS lookups
      consistent among the various ways to launch DNS lookups. Fixes
      bug 8203; bugfix on 0.2.0.24-rc. Patch by "Desoxy".
    - Correct our check for which versions of Tor support the EXTEND2
      cell. We had been willing to send it to Tor 0.2.4.7-alpha and
      later, when support was really added in version 0.2.4.8-alpha.
      Fixes bug 8464; bugfix on 0.2.4.8-alpha.

  o Minor bugfixes (other):
    - Correctly store microdescriptors and extrainfo descriptors with
      an internal NUL byte. Fixes bug 8037; bugfix on 0.2.0.1-alpha.
      Bug reported by "cypherpunks".
    - Increase the width of the field used to remember a connection's
      link protocol version to two bytes. Harmless for now, since the
      only currently recognized versions are one byte long. Reported
      pseudonymously. Fixes bug 8062; bugfix on 0.2.0.10-alpha.
    - If the state file's path bias counts are invalid (presumably from a
      buggy Tor prior to 0.2.4.10-alpha), make them correct. Also add
      additional checks and log messages to the scaling of Path Bias
      counts, in case there still are remaining issues with scaling.
      Should help resolve bug 8235.
    - Eliminate several instances where we use "Nickname=ID" to refer to
      nodes in logs. Use "Nickname (ID)" instead. (Elsewhere, we still use
      "$ID=Nickname", which is also acceptable.) Fixes bug 7065. Bugfix
      on 0.2.3.21-rc, 0.2.4.5-alpha, 0.2.4.8-alpha, and 0.2.4.10-alpha.

  o Minor bugfixes (syscalls):
    - Always check the return values of functions fcntl() and
      setsockopt(). We don't believe these are ever actually failing in
      practice, but better safe than sorry. Also, checking these return
      values should please analysis tools like Coverity. Patch from
      'flupzor'. Fixes bug 8206; bugfix on all versions of Tor.
    - Use direct writes rather than stdio when building microdescriptor
      caches, in an attempt to mitigate bug 8031, or at least make it
      less common.

  o Minor bugfixes (config):
    - When rejecting a configuration because we were unable to parse a
      quoted string, log an actual error message. Fixes bug 7950; bugfix
      on 0.2.0.16-alpha.
    - Behave correctly when the user disables LearnCircuitBuildTimeout
      but doesn't tell us what they would like the timeout to be. Fixes
      bug 6304; bugfix on 0.2.2.14-alpha.
    - When autodetecting the number of CPUs, use the number of available
      CPUs in preference to the number of configured CPUs. Inform the
      user if this reduces the number of available CPUs. Fixes bug 8002;
      bugfix on 0.2.3.1-alpha.
    - Make it an error when you set EntryNodes but disable UseGuardNodes,
      since it will (surprisingly to some users) ignore EntryNodes. Fixes
      bug 8180; bugfix on 0.2.3.11-alpha.
    - Allow TestingTorNetworks to override the 4096-byte minimum for
      the Fast threshold. Otherwise they can't bootstrap until they've
      observed more traffic. Fixes bug 8508; bugfix on 0.2.4.10-alpha.
    - Fix some logic errors when the user manually overrides the
      PathsNeededToBuildCircuits option in torrc. Fixes bug 8599; bugfix
      on 0.2.4.10-alpha.

  o Minor bugfixes (log messages to help diagnose bugs):
    - If we fail to free a microdescriptor because of bug 7164, log
      the filename and line number from which we tried to free it.
    - Add another diagnostic to the heartbeat message: track and log
      overhead that TLS is adding to the data we write. If this is
      high, we are sending too little data to SSL_write at a time.
      Diagnostic for bug 7707.
    - Add more detail to a log message about relaxed timeouts, to help
      track bug 7799.
    - Warn more aggressively when flushing microdescriptors to a
      microdescriptor cache fails, in an attempt to mitigate bug 8031,
      or at least make it more diagnosable.
    - Improve debugging output to help track down bug 8185 ("Bug:
      outgoing relay cell has n_chan==NULL. Dropping.")
    - Log the purpose of a path-bias testing circuit correctly.
      Improves a log message from bug 8477; bugfix on 0.2.4.8-alpha.

  o Minor bugfixes (0.2.4.x log messages that were too noisy):
    - Don't attempt to relax the timeout of already opened 1-hop circuits.
      They might never timeout. This should eliminate some/all cases of
      the relaxed timeout log message.
    - Use circuit creation time for network liveness evaluation. This
      should eliminate warning log messages about liveness caused
      by changes in timeout evaluation. Fixes bug 6572; bugfix on
      0.2.4.8-alpha.
    - Reduce a path bias length check from notice to info. The message
      is triggered when creating controller circuits. Fixes bug 8196;
      bugfix on 0.2.4.8-alpha.
    - Fix a path state issue that triggered a notice during relay startup.
      Fixes bug 8320; bugfix on 0.2.4.10-alpha.
    - Reduce occurrences of warns about circuit purpose in
      connection_ap_expire_building(). Fixes bug 8477; bugfix on
      0.2.4.11-alpha.

  o Minor bugfixes (pre-0.2.4.x log messages that were too noisy):
    - If we encounter a write failure on a SOCKS connection before we
      finish our SOCKS handshake, don't warn that we closed the
      connection before we could send a SOCKS reply. Fixes bug 8427;
      bugfix on 0.1.0.1-rc.
    - Correctly recognize that [::1] is a loopback address. Fixes
      bug 8377; bugfix on 0.2.1.3-alpha.
    - Fix a directory authority warn caused when we have a large amount
      of badexit bandwidth. Fixes bug 8419; bugfix on 0.2.2.10-alpha.
    - Don't log inappropriate heartbeat messages when hibernating: a
      hibernating node is _expected_ to drop out of the consensus,
      decide it isn't bootstrapped, and so forth. Fixes bug 7302;
      bugfix on 0.2.3.1-alpha.
    - Don't complain about bootstrapping problems while hibernating.
      These complaints reflect a general code problem, but not one
      with any problematic effects (no connections are actually
      opened). Fixes part of bug 7302; bugfix on 0.2.3.2-alpha.

  o Documentation fixes:
    - Update tor-fw-helper.1.txt and tor-fw-helper.c to make option
      names match. Fixes bug 7768.
    - Make the torify manpage no longer refer to tsocks; torify hasn't
      supported tsocks since 0.2.3.14-alpha.
    - Make the tor manpage no longer reference tsocks.
    - Fix the GeoIPExcludeUnknown documentation to refer to
      ExcludeExitNodes rather than the currently nonexistent
      ExcludeEntryNodes. Spotted by "hamahangi" on tor-talk.

  o Removed files:
    - The tor-tsocks.conf is no longer distributed or installed. We
      recommend that tsocks users use torsocks instead. Resolves
      ticket 8290.


Changes in version 0.2.4.11-alpha - 2013-03-11
  Tor 0.2.4.11-alpha makes relay measurement by directory authorities
  more robust, makes hidden service authentication work again, and
  resolves a DPI fingerprint for Tor's SSL transport.

  o Major features (directory authorities):
    - Directory authorities now support a new consensus method (17)
      where they cap the published bandwidth of servers for which
      insufficient bandwidth measurements exist. Fixes part of bug 2286.
    - Directory authorities that set "DisableV2DirectoryInfo_ 1" no longer
      serve any v2 directory information. Now we can test disabling the
      old deprecated v2 directory format, and see whether doing so has
      any effect on network load. Begins to fix bug 6783.
    - Directory authorities now include inside each vote a statement of
      the performance thresholds they used when assigning flags.
      Implements ticket 8151.

  o Major bugfixes (directory authorities):
    - Stop marking every relay as having been down for one hour every
      time we restart a directory authority. These artificial downtimes
      were messing with our Stable and Guard flag calculations. Fixes
      bug 8218 (introduced by the fix for 1035). Bugfix on 0.2.2.23-alpha.

  o Major bugfixes (hidden services):
    - Allow hidden service authentication to succeed again. When we
      refactored the hidden service introduction code back
      in 0.2.4.1-alpha, we didn't update the code that checks
      whether authentication information is present, causing all
      authentication checks to return "false". Fix for bug 8207; bugfix
      on 0.2.4.1-alpha. Found by Coverity; this is CID 718615.

  o Minor features (relays, bridges):
    - Make bridge relays check once a minute for whether their IP
      address has changed, rather than only every 15 minutes. Resolves
      bugs 1913 and 1992.
    - Refactor resolve_my_address() so it returns the method by which we
      decided our public IP address (explicitly configured, resolved from
      explicit hostname, guessed from interfaces, learned by gethostname).
      Now we can provide more helpful log messages when a relay guesses
      its IP address incorrectly (e.g. due to unexpected lines in
      /etc/hosts). Resolves ticket 2267.
    - Teach bridge-using clients to avoid 0.2.2 bridges when making
      microdescriptor-related dir requests, and only fall back to normal
      descriptors if none of their bridges can handle microdescriptors
      (as opposed to the fix in ticket 4013, which caused them to fall
      back to normal descriptors if *any* of their bridges preferred
      them). Resolves ticket 4994.
    - Randomize the lifetime of our SSL link certificate, so censors can't
      use the static value for filtering Tor flows. Resolves ticket 8443;
      related to ticket 4014 which was included in 0.2.2.33.
    - Support a new version of the link protocol that allows 4-byte circuit
      IDs. Previously, circuit IDs were limited to 2 bytes, which presented
      a possible resource exhaustion issue. Closes ticket 7351; implements
      proposal 214.

  o Minor features (portability):
    - Tweak the curve25519-donna*.c implementations to tolerate systems
      that lack stdint.h. Fixes bug 3894; bugfix on 0.2.4.8-alpha.
    - Use Ville Laurikari's implementation of AX_CHECK_SIGN() to determine
      the signs of types during autoconf. This is better than our old
      approach, which didn't work when cross-compiling.
    - Detect the sign of enum values, rather than assuming that MSC is the
      only compiler where enum types are all signed. Fixes bug 7727;
      bugfix on 0.2.4.10-alpha.

  o Minor features (other):
    - Say "KBytes" rather than "KB" in the man page (for various values
      of K), to further reduce confusion about whether Tor counts in
      units of memory or fractions of units of memory. Resolves ticket 7054.
    - Clear the high bit on curve25519 public keys before passing them to
      our backend, in case we ever wind up using a backend that doesn't do
      so itself. If we used such a backend, and *didn't* clear the high bit,
      we could wind up in a situation where users with such backends would
      be distinguishable from users without. Fixes bug 8121; bugfix on
      0.2.4.8-alpha.
    - Update to the March 6 2013 Maxmind GeoLite Country database.

  o Minor bugfixes (clients):
    - When we receive a RELAY_END cell with the reason DONE, or with no
      reason, before receiving a RELAY_CONNECTED cell, report the SOCKS
      status as "connection refused". Previously we reported these cases
      as success but then immediately closed the connection. Fixes bug
      7902; bugfix on 0.1.0.1-rc. Reported by "oftc_must_be_destroyed".
    - Downgrade an assertion in connection_ap_expire_beginning to an
      LD_BUG message. The fix for bug 8024 should prevent this message
      from displaying, but just in case, a warn that we can diagnose
      is better than more assert crashes. Fixes bug 8065; bugfix on
      0.2.4.8-alpha.
    - Lower path use bias thresholds to .80 for notice and .60 for warn.
      Also make the rate limiting flags for the path use bias log messages
      independent from the original path bias flags. Fixes bug 8161;
      bugfix on 0.2.4.10-alpha.

  o Minor bugfixes (relays):
    - Stop trying to resolve our hostname so often (e.g. every time we
      think about doing a directory fetch). Now we reuse the cached
      answer in some cases. Fixes bugs 1992 (bugfix on 0.2.0.20-rc)
      and 2410 (bugfix on 0.1.2.2-alpha).
    - Stop sending a stray "(null)" in some cases for the server status
      "EXTERNAL_ADDRESS" controller event. Resolves bug 8200; bugfix
      on 0.1.2.6-alpha.
    - When choosing which stream on a formerly stalled circuit to wake
      first, make better use of the platform's weak RNG. Previously,
      we had been using the % ("modulo") operator to try to generate a
      1/N chance of picking each stream, but this behaves badly with
      many platforms' choice of weak RNG. Fixes bug 7801; bugfix on
      0.2.2.20-alpha.
    - Use our own weak RNG when we need a weak RNG. Windows's rand() and
      Irix's random() only return 15 bits; Solaris's random() returns more
      bits but its RAND_MAX says it only returns 15, and so on. Motivated
      by the fix for bug 7801; bugfix on 0.2.2.20-alpha.

  o Minor bugfixes (directory authorities):
    - Directory authorities now use less space when formatting identical
      microdescriptor lines in directory votes. Fixes bug 8158; bugfix
      on 0.2.4.1-alpha.

  o Minor bugfixes (memory leaks spotted by Coverity -- bug 7816):
    - Avoid leaking memory if we fail to compute a consensus signature
      or we generate a consensus we can't parse. Bugfix on 0.2.0.5-alpha.
    - Fix a memory leak when receiving headers from an HTTPS proxy. Bugfix
      on 0.2.1.1-alpha.
    - Fix a memory leak during safe-cookie controller authentication.
      Bugfix on 0.2.3.13-alpha.
    - Avoid memory leak of IPv6 policy content if we fail to format it into
      a router descriptor. Bugfix on 0.2.4.7-alpha.

  o Minor bugfixes (other code correctness issues):
    - Avoid a crash if we fail to generate an extrainfo descriptor.
      Fixes bug 8208; bugfix on 0.2.3.16-alpha. Found by Coverity;
      this is CID 718634.
    - When detecting the largest possible file descriptor (in order to
      close all file descriptors when launching a new program), actually
      use _SC_OPEN_MAX. The old code for doing this was very, very broken.
      Fixes bug 8209; bugfix on 0.2.3.1-alpha. Found by Coverity; this
      is CID 743383.
    - Fix a copy-and-paste error when adding a missing A1 to a routerset
      because of GeoIPExcludeUnknown. Fix for Coverity CID 980650.
      Bugfix on 0.2.4.10-alpha.
    - Fix an impossible-to-trigger integer overflow when estimating how
      long our onionskin queue would take. (This overflow would require us
      to accept 4 million onionskins before processing 100 of them.) Fixes
      bug 8210; bugfix on 0.2.4.10-alpha.

  o Code simplification and refactoring:
    - Add a wrapper function for the common "log a message with a
      rate-limit" case.


Changes in version 0.2.4.10-alpha - 2013-02-04
  Tor 0.2.4.10-alpha adds defenses at the directory authority level from
  certain attacks that flood the network with relays; changes the queue
  for circuit create requests from a sized-based limit to a time-based
  limit; resumes building with MSVC on Windows; and fixes a wide variety
  of other issues.

  o Major bugfixes (directory authority):
    - When computing directory thresholds, ignore any rejected-as-sybil
      nodes during the computation so that they can't influence Fast,
      Guard, etc. (We should have done this for proposal 109.) Fixes
      bug 8146.
    - When marking a node as a likely sybil, reset its uptime metrics
      to zero, so that it cannot time towards getting marked as Guard,
      Stable, or HSDir. (We should have done this for proposal 109.) Fixes
      bug 8147.

  o Major bugfixes:
    - When a TLS write is partially successful but incomplete, remember
      that the flushed part has been flushed, and notice that bytes were
      actually written. Reported and fixed pseudonymously. Fixes bug
      7708; bugfix on Tor 0.1.0.5-rc.
    - Reject bogus create and relay cells with 0 circuit ID or 0 stream
      ID: these could be used to create unexpected streams and circuits
      which would count as "present" to some parts of Tor but "absent"
      to others, leading to zombie circuits and streams or to a bandwidth
      denial-of-service. Fixes bug 7889; bugfix on every released version
      of Tor. Reported by "oftc_must_be_destroyed".
    - Rename all macros in our local copy of queue.h to begin with "TOR_".
      This change seems the only good way to permanently prevent conflicts
      with queue.h on various operating systems. Fixes bug 8107; bugfix
      on 0.2.4.6-alpha.

  o Major features (relay):
    - Instead of limiting the number of queued onionskins (aka circuit
      create requests) to a fixed, hard-to-configure number, we limit
      the size of the queue based on how many we expect to be able to
      process in a given amount of time. We estimate the time it will
      take to process an onionskin based on average processing time
      of previous onionskins. Closes ticket 7291. You'll never have to
      configure MaxOnionsPending again.

  o Major features (portability):
    - Resume building correctly with MSVC and Makefile.nmake. This patch
      resolves numerous bugs and fixes reported by ultramage, including
      7305, 7308, 7309, 7310, 7312, 7313, 7315, 7316, and 7669.
    - Make the ntor and curve25519 code build correctly with MSVC.
      Fix on 0.2.4.8-alpha.

  o Minor features:
    - When directory authorities are computing thresholds for flags,
      never let the threshold for the Fast flag fall below 4096
      bytes. Also, do not consider nodes with extremely low bandwidths
      when deciding thresholds for various directory flags. This change
      should raise our threshold for Fast relays, possibly in turn
      improving overall network performance; see ticket 1854. Resolves
      ticket 8145.
    - The Tor client now ignores sub-domain components of a .onion
      address. This change makes HTTP "virtual" hosting
      possible: http://foo.aaaaaaaaaaaaaaaa.onion/ and
      http://bar.aaaaaaaaaaaaaaaa.onion/ can be two different websites
      hosted on the same hidden service. Implements proposal 204.
    - We compute the overhead from passing onionskins back and forth to
      cpuworkers, and report it when dumping statistics in response to
      SIGUSR1. Supports ticket 7291.

  o Minor features (path selection):
    - When deciding whether we have enough descriptors to build circuits,
      instead of looking at raw relay counts, look at which fraction
      of (bandwidth-weighted) paths we're able to build. This approach
      keeps clients from building circuits if their paths are likely to
      stand out statistically. The default fraction of paths needed is
      taken from the consensus directory; you can override it with the
      new PathsNeededToBuildCircuits option. Fixes ticket 5956.
    - When any country code is listed in ExcludeNodes or ExcludeExitNodes,
      and we have GeoIP information, also exclude all nodes with unknown
      countries "??" and "A1". This behavior is controlled by the
      new GeoIPExcludeUnknown option: you can make such nodes always
      excluded with "GeoIPExcludeUnknown 1", and disable the feature
      with "GeoIPExcludeUnknown 0". Setting "GeoIPExcludeUnknown auto"
      gets you the default behavior. Implements feature 7706.
    - Path Use Bias: Perform separate accounting for successful circuit
      use. Keep separate statistics on stream attempt rates versus stream
      success rates for each guard. Provide configurable thresholds to
      determine when to emit log messages or disable use of guards that
      fail too many stream attempts. Resolves ticket 7802.

  o Minor features (log messages):
    - When learning a fingerprint for a bridge, log its corresponding
      transport type. Implements ticket 7896.
    - Improve the log message when "Bug/attack: unexpected sendme cell
      from client" occurs, to help us track bug 8093.

  o Minor bugfixes:
    - Remove a couple of extraneous semicolons that were upsetting the
      cparser library. Patch by Christian Grothoff. Fixes bug 7115;
      bugfix on 0.2.2.1-alpha.
    - Remove a source of rounding error during path bias count scaling;
      don't count cannibalized circuits as used for path bias until we
      actually try to use them; and fix a circuit_package_relay_cell()
      warning message about n_chan==NULL. Fixes bug 7802.
    - Detect nacl when its headers are in a nacl/ subdirectory. Also,
      actually link against nacl when we're configured to use it. Fixes
      bug 7972; bugfix on 0.2.4.8-alpha.
    - Compile correctly with the --disable-curve25519 option. Fixes
      bug 8153; bugfix on 0.2.4.8-alpha.

  o Build improvements:
    - Do not report status verbosely from autogen.sh unless the -v flag
      is specified. Fixes issue 4664. Patch from Onizuka.
    - Replace all calls to snprintf() outside of src/ext with
      tor_snprintf(). Also remove the #define to replace snprintf with
      _snprintf on Windows; they have different semantics, and all of
      our callers should be using tor_snprintf() anyway. Fixes bug 7304.
    - Try to detect if we are ever building on a platform where
      memset(...,0,...) does not set the value of a double to 0.0. Such
      platforms are permitted by the C standard, though in practice
      they're pretty rare (since IEEE 754 is nigh-ubiquitous). We don't
      currently support them, but it's better to detect them and fail
      than to perform erroneously.

  o Removed features:
    - Stop exporting estimates of v2 and v3 directory traffic shares
      in extrainfo documents. They were unneeded and sometimes inaccurate.
      Also stop exporting any v2 directory request statistics. Resolves
      ticket 5823.
    - Drop support for detecting and warning about versions of Libevent
      before 1.3e. Nothing reasonable ships with them any longer;
      warning the user about them shouldn't be needed. Resolves ticket
      6826.

  o Code simplifications and refactoring:
    - Rename "isin" functions to "contains", for grammar. Resolves
      ticket 5285.
    - Rename Tor's logging function log() to tor_log(), to avoid conflicts
      with the natural logarithm function from the system libm. Resolves
      ticket 7599.


Changes in version 0.2.4.9-alpha - 2013-01-15
  Tor 0.2.4.9-alpha provides a quick fix to make the new ntor handshake
  work more robustly.

  o Major bugfixes:
    - Fix backward compatibility logic when receiving an embedded ntor
      handshake tunneled in a CREATE cell. This clears up the "Bug:
      couldn't format CREATED cell" warning. Fixes bug 7959; bugfix
      on 0.2.4.8-alpha.


Changes in version 0.2.4.8-alpha - 2013-01-14
  Tor 0.2.4.8-alpha introduces directory guards to reduce user enumeration
  risks, adds a new stronger and faster circuit handshake, and offers
  stronger and faster link encryption when both sides support it.

  o Major features:
    - Preliminary support for directory guards (proposal 207): when
      possible, clients now use their entry guards for non-anonymous
      directory requests. This can help prevent client enumeration. Note
      that this behavior only works when we have a usable consensus
      directory, and when options about what to download are more or less
      standard. In the future we should re-bootstrap from our guards,
      rather than re-bootstrapping from the preconfigured list of
      directory sources that ships with Tor. Resolves ticket 6526.
    - Tor relays and clients now support a better CREATE/EXTEND cell
      format, allowing the sender to specify multiple address, identity,
      and handshake types. Implements Robert Ransom's proposal 200;
      closes ticket 7199.

  o Major features (new circuit handshake):
    - Tor now supports a new circuit extension handshake designed by Ian
      Goldberg, Douglas Stebila, and Berkant Ustaoglu. Our original
      circuit extension handshake, later called "TAP", was a bit slow
      (especially on the relay side), had a fragile security proof, and
      used weaker keys than we'd now prefer. The new circuit handshake
      uses Dan Bernstein's "curve25519" elliptic-curve Diffie-Hellman
      function, making it significantly more secure than the older
      handshake, and significantly faster. Tor can use one of two built-in
      pure-C curve25519-donna implementations by Adam Langley, or it
      can link against the "nacl" library for a tuned version if present.

      The built-in version is very fast for 64-bit systems when building
      with GCC. The built-in 32-bit version is still faster than the
      old TAP protocol, but using libnacl is better on most such hosts.

      Clients don't currently use this protocol by default, since
      comparatively few clients support it so far. To try it, set
      UseNTorHandshake to 1.

      Implements proposal 216; closes ticket 7202.

  o Major features (better link encryption):
    - Relays can now enable the ECDHE TLS ciphersuites when available
      and appropriate. These ciphersuites let us negotiate forward-secure
      TLS secret keys more safely and more efficiently than with our
      previous use of Diffie-Hellman modulo a 1024-bit prime. By default,
      public relays prefer the (faster) P224 group, and bridges prefer
      the (more common) P256 group; you can override this with the
      TLSECGroup option.

      Enabling these ciphers was a little tricky, since for a long time,
      clients had been claiming to support them without actually doing
      so, in order to foil fingerprinting. But with the client-side
      implementation of proposal 198 in 0.2.3.17-beta, clients can now
      match the ciphers from recent Firefox versions *and* list the
      ciphers they actually mean, so relays can believe such clients
      when they advertise ECDHE support in their TLS ClientHello messages.

      This feature requires clients running 0.2.3.17-beta or later,
      and requires both sides to be running OpenSSL 1.0.0 or later
      with ECC support. OpenSSL 1.0.1, with the compile-time option
      "enable-ec_nistp_64_gcc_128", is highly recommended.

      Implements the relay side of proposal 198; closes ticket 7200.

  o Major bugfixes:
    - Avoid crashing when, as a relay without IPv6-exit support, a
      client insists on getting an IPv6 address or nothing. Fixes bug
      7814; bugfix on 0.2.4.7-alpha.

  o Minor features:
    - Improve circuit build timeout handling for hidden services.
      In particular: adjust build timeouts more accurately depending
      upon the number of hop-RTTs that a particular circuit type
      undergoes. Additionally, launch intro circuits in parallel
      if they timeout, and take the first one to reply as valid.
    - Work correctly on Unix systems where EAGAIN and EWOULDBLOCK are
      separate error codes; or at least, don't break for that reason.
      Fixes bug 7935. Reported by "oftc_must_be_destroyed".
    - Update to the January 2 2013 Maxmind GeoLite Country database.

  o Minor features (testing):
    - Add benchmarks for DH (1024-bit multiplicative group) and ECDH
      (P-256) Diffie-Hellman handshakes to src/or/bench.
    - Add benchmark functions to test onion handshake performance.

  o Minor features (path bias detection):
    - Alter the Path Bias log messages to be more descriptive in terms
      of reporting timeouts and other statistics.
    - Create three levels of Path Bias log messages, as opposed to just
      two. These are configurable via consensus as well as via the torrc
      options PathBiasNoticeRate, PathBiasWarnRate, PathBiasExtremeRate.
      The default values are 0.70, 0.50, and 0.30 respectively.
    - Separate the log message levels from the decision to drop guards,
      which also is available via torrc option PathBiasDropGuards.
      PathBiasDropGuards still defaults to 0 (off).
    - Deprecate PathBiasDisableRate in favor of PathBiasDropGuards
      in combination with PathBiasExtremeRate.
    - Increase the default values for PathBiasScaleThreshold and
      PathBiasCircThreshold from (200, 20) to (300, 150).
    - Add in circuit usage accounting to path bias. If we try to use a
      built circuit but fail for any reason, it counts as path bias.
      Certain classes of circuits where the adversary gets to pick your
      destination node are exempt from this accounting. Usage accounting
      can be specifically disabled via consensus parameter or torrc.
    - Convert all internal path bias state to double-precision floating
      point, to avoid roundoff error and other issues.
    - Only record path bias information for circuits that have completed
      *two* hops. Assuming end-to-end tagging is the attack vector, this
      makes us more resilient to ambient circuit failure without any
      detection capability loss.

  o Minor bugfixes (log messages):
    - Rate-limit the "No circuits are opened. Relaxed timeout for a
      circuit with channel state open..." message to once per hour to
      keep it from filling the notice logs. Mitigates bug 7799 but does
      not fix the underlying cause. Bugfix on 0.2.4.7-alpha.
    - Avoid spurious warnings when configuring multiple client ports of
      which only some are nonlocal. Previously, we had claimed that some
      were nonlocal when in fact they weren't. Fixes bug 7836; bugfix on
      0.2.3.3-alpha.

  o Code simplifications and refactoring:
    - Get rid of a couple of harmless clang warnings, where we compared
      enums to ints. These warnings are newly introduced in clang 3.2.
    - Split the onion.c file into separate modules for the onion queue
      and the different handshakes it supports.
    - Remove the marshalling/unmarshalling code for sending requests to
      cpuworkers over a socket, and instead just send structs. The
      recipient will always be the same Tor binary as the sender, so
      any encoding is overkill.


Changes in version 0.2.4.7-alpha - 2012-12-24
  Tor 0.2.4.7-alpha introduces a new approach to providing fallback
  directory mirrors for more robust bootstrapping; fixes more issues where
  clients with changing network conditions refuse to make any circuits;
  adds initial support for exiting to IPv6 addresses; resumes being able
  to update our GeoIP database, and includes the geoip6 file this time;
  turns off the client-side DNS cache by default due to privacy risks;
  and fixes a variety of other issues.

  o Major features (client resilience):
    - Add a new "FallbackDir" torrc option to use when we can't use
      a directory mirror from the consensus (either because we lack a
      consensus, or because they're all down). Currently, all authorities
      are fallbacks by default, and there are no other default fallbacks,
      but that will change. This option will allow us to give clients a
      longer list of servers to try to get a consensus from when first
      connecting to the Tor network, and thereby reduce load on the
      directory authorities. Implements proposal 206, "Preconfigured
      directory sources for bootstrapping". We also removed the old
      "FallbackNetworkstatus" option, since we never got it working well
      enough to use it. Closes bug 572.
    - If we have no circuits open, use a relaxed timeout (the
      95-percentile cutoff) until a circuit succeeds. This heuristic
      should allow Tor to succeed at building circuits even when the
      network connection drastically changes. Should help with bug 3443.

  o Major features (IPv6):
    - Relays can now exit to IPv6 addresses: make sure that you have IPv6
      connectivity, then set the IPv6Exit flag to 1. Also make sure your
      exit policy reads as you would like: the address * applies to all
      address families, whereas *4 is IPv4 address only, and *6 is IPv6
      addresses only. On the client side, you'll need to wait until the
      authorities have upgraded, wait for enough exits to support IPv6,
      apply the "IPv6Traffic" flag to a SocksPort, and use Socks5. Closes
      ticket 5547, implements proposal 117 as revised in proposal 208.

      We DO NOT recommend that clients with actual anonymity needs start
      using IPv6 over Tor yet, since not enough exits support it yet.

  o Major features (geoip database):
    - Maxmind began labelling Tor relays as being in country "A1",
      which breaks by-country node selection inside Tor. Now we use a
      script to replace "A1" ("Anonymous Proxy") entries in our geoip
      file with real country codes. This script fixes about 90% of "A1"
      entries automatically and uses manual country code assignments to
      fix the remaining 10%. See src/config/README.geoip for details.
      Fixes bug 6266. Also update to the December 5 2012 Maxmind GeoLite
      Country database, as modified above.

  o Major bugfixes (client-side DNS):
    - Turn off the client-side DNS cache by default. Updating and using
      the DNS cache is now configurable on a per-client-port
      level. SOCKSPort, DNSPort, etc lines may now contain
      {No,}Cache{IPv4,IPv6,}DNS lines to indicate that we shouldn't
      cache these types of DNS answers when we receive them from an
      exit node in response to an application request on this port, and
      {No,}UseCached{IPv4,IPv6,DNS} lines to indicate that if we have
      cached DNS answers of these types, we shouldn't use them. It's
      potentially risky to use cached DNS answers at the client, since
      doing so can indicate to one exit what answers we've gotten
      for DNS lookups in the past. With IPv6, this becomes especially
      problematic. Using cached DNS answers for requests on the same
      circuit would present less linkability risk, since all traffic
      on a circuit is already linkable, but it would also provide
      little performance benefit: the exit node caches DNS replies
      too. Implements a simplified version of Proposal 205. Implements
      ticket 7570.

  o Major bugfixes (other):
    - Alter circuit build timeout measurement to start at the point
      where we begin the CREATE/CREATE_FAST step (as opposed to circuit
      initialization). This should make our timeout measurements more
      uniform. Previously, we were sometimes including ORconn setup time
      in our circuit build time measurements. Should resolve bug 3443.
    - Fix an assertion that could trigger in hibernate_go_dormant() when
      closing an or_connection_t: call channel_mark_for_close() rather
      than connection_mark_for_close(). Fixes bug 7267. Bugfix on
      0.2.4.4-alpha.
    - Include the geoip6 IPv6 GeoIP database in the tarball. Fixes bug
      7655; bugfix on 0.2.4.6-alpha.

  o Minor features:
    - Add a new torrc option "ServerTransportListenAddr" to let bridge
      operators select the address where their pluggable transports will
      listen for connections. Resolves ticket 7013.
    - Allow an optional $ before the node identity digest in the
      controller command GETINFO ns/id/, for consistency with
      md/id/ and desc/id/. Resolves ticket 7059.
    - Log packaged cell fullness as part of the heartbeat message.
      Diagnosis to try to determine the extent of bug 7743.

  o Minor features (IPv6):
    - AutomapHostsOnResolve now supports IPv6 addresses. By default, we
      prefer to hand out virtual IPv6 addresses, since there are more of
      them and we can't run out. To override this behavior and make IPv4
      addresses preferred, set NoPreferIPv6Automap on whatever SOCKSPort
      or DNSPort you're using for resolving. Implements ticket 7571.
    - AutomapHostsOnResolve responses are now randomized, to avoid
      annoying situations where Tor is restarted and applications
      connect to the wrong addresses.
    - Never try more than 1000 times to pick a new virtual address when
      AutomapHostsOnResolve is set. That's good enough so long as we
      aren't close to handing out our entire virtual address space;
      if you're getting there, it's best to switch to IPv6 virtual
      addresses anyway.

  o Minor bugfixes:
    - The ADDRMAP command can no longer generate an ill-formed error
      code on a failed MAPADDRESS. It now says "internal" rather than
      an English sentence fragment with spaces in the middle. Bugfix on
      Tor 0.2.0.19-alpha.
    - Fix log messages and comments to avoid saying "GMT" when we mean
      "UTC". Fixes bug 6113.
    - Compile on win64 using mingw64. Fixes bug 7260; patches from
      "yayooo".
    - Fix a crash when debugging unit tests on Windows: deallocate a
      shared library with FreeLibrary, not CloseHandle. Fixes bug 7306;
      bugfix on 0.2.2.17-alpha. Reported by "ultramage".

  o Renamed options:
    - The DirServer option is now DirAuthority, for consistency with
      current naming patterns. You can still use the old DirServer form.

  o Code simplification and refactoring:
    - Move the client-side address-map/virtual-address/DNS-cache code
      out of connection_edge.c into a new addressmap.c module.
    - Remove unused code for parsing v1 directories and "running routers"
      documents. Fixes bug 6887.


Changes in version 0.2.3.25 - 2012-11-19
  The Tor 0.2.3 release series is dedicated to the memory of Len "rabbi"
  Sassaman (1980-2011), a long-time cypherpunk, anonymity researcher,
  Mixmaster maintainer, Pynchon Gate co-designer, CodeCon organizer,
  programmer, and friend. Unstinting in his dedication to the cause of
  freedom, he inspired and helped many of us as we began our work on
  anonymity, and inspires us still. Please honor his memory by writing
  software to protect people's freedoms, and by helping others to do so.

  Tor 0.2.3.25, the first stable release in the 0.2.3 branch, features
  significantly reduced directory overhead (via microdescriptors),
  enormous crypto performance improvements for fast relays on new
  enough hardware, a new v3 TLS handshake protocol that can better
  resist fingerprinting, support for protocol obfuscation plugins (aka
  pluggable transports), better scalability for hidden services, IPv6
  support for bridges, performance improvements like allowing clients
  to skip the first round-trip on the circuit ("optimistic data") and
  refilling token buckets more often, a new "stream isolation" design
  to isolate different applications on different circuits, and many
  stability, security, and privacy fixes.

  o Major bugfixes:
    - Tor tries to wipe potentially sensitive data after using it, so
      that if some subsequent security failure exposes Tor's memory,
      the damage will be limited. But we had a bug where the compiler
      was eliminating these wipe operations when it decided that the
      memory was no longer visible to a (correctly running) program,
      hence defeating our attempt at defense in depth. We fix that
      by using OpenSSL's OPENSSL_cleanse() operation, which a compiler
      is unlikely to optimize away. Future versions of Tor may use
      a less ridiculously heavy approach for this. Fixes bug 7352.
      Reported in an article by Andrey Karpov.

  o Minor bugfixes:
    - Fix a harmless bug when opting against publishing a relay descriptor
      because DisableNetwork is set. Fixes bug 7464; bugfix on
      0.2.3.9-alpha.


Changes in version 0.2.4.6-alpha - 2012-11-13
  Tor 0.2.4.6-alpha fixes an assert bug that has been plaguing relays,
  makes our defense-in-depth memory wiping more reliable, and begins to
  count IPv6 addresses in bridge statistics,

  o Major bugfixes:
    - Fix an assertion failure that could occur when closing a connection
      with a spliced rendezvous circuit. Fix for bug 7212; bugfix on
      Tor 0.2.4.4-alpha.
    - Tor tries to wipe potentially sensitive data after using it, so
      that if some subsequent security failure exposes Tor's memory,
      the damage will be limited. But we had a bug where the compiler
      was eliminating these wipe operations when it decided that the
      memory was no longer visible to a (correctly running) program,
      hence defeating our attempt at defense in depth. We fix that
      by using OpenSSL's OPENSSL_cleanse() operation, which a compiler
      is unlikely to optimize away. Future versions of Tor may use
      a less ridiculously heavy approach for this. Fixes bug 7352.
      Reported in an article by Andrey Karpov.

  o Minor features:
    - Add GeoIP database for IPv6 addresses. The new config option
      is GeoIPv6File.
    - Bridge statistics now count bridge clients connecting over IPv6:
      bridge statistics files now list "bridge-ip-versions" and
      extra-info documents list "geoip6-db-digest". The control protocol
      "CLIENTS_SEEN" and "ip-to-country" queries now support IPv6. Initial
      implementation by "shkoo", addressing ticket 5055.

  o Minor bugfixes:
    - Warn when we are binding low ports when hibernation is enabled;
      previously we had warned when we were _advertising_ low ports with
      hibernation enabled. Fixes bug 7285; bugfix on 0.2.3.9-alpha.
    - Fix a harmless bug when opting against publishing a relay descriptor
      because DisableNetwork is set. Fixes bug 7464; bugfix on
      0.2.3.9-alpha.
    - Add warning message when a managed proxy dies during configuration.
      Fixes bug 7195; bugfix on 0.2.4.2-alpha.
    - Fix a linking error when building tor-fw-helper without miniupnp.
      Fixes bug 7235; bugfix on 0.2.4.2-alpha. Fix by Anthony G. Basile.
    - Check for closing an or_connection_t without going through correct
      channel functions; emit a warning and then call
      connection_or_close_for_error() so we don't assert as in bugs 7212
      and 7267.
    - Compile correctly on compilers without C99 designated initializer
      support. Fixes bug 7286; bugfix on 0.2.4.4-alpha.
    - Avoid a possible assert that can occur when channel_send_destroy() is
      called on a channel in CHANNEL_STATE_CLOSING, CHANNEL_STATE_CLOSED,
      or CHANNEL_STATE_ERROR when the Tor process is resumed after being
      blocked for a long interval. Fixes bug 7350; bugfix on 0.2.4.4-alpha.
    - Fix a memory leak on failing cases of channel_tls_process_certs_cell.
      Fixes bug 7422; bugfix on 0.2.4.4-alpha.

  o Code simplification and refactoring:
    - Start using OpenBSD's implementation of queue.h, so that we don't
      need to hand-roll our own pointer and list structures whenever we
      need them. (We can't rely on a sys/queue.h, since some operating
      systems don't have them, and the ones that do have them don't all
      present the same extensions.)


Changes in version 0.2.4.5-alpha - 2012-10-25
  Tor 0.2.4.5-alpha comes hard at the heels of 0.2.4.4-alpha, to fix
  two important security vulnerabilities that could lead to remotely
  triggerable relay crashes, fix a major bug that was preventing clients
  from choosing suitable exit nodes, and refactor some of our code.

  o Major bugfixes (security, also in 0.2.3.24-rc):
    - Fix a group of remotely triggerable assertion failures related to
      incorrect link protocol negotiation. Found, diagnosed, and fixed
      by "some guy from France". Fix for CVE-2012-2250; bugfix on
      0.2.3.6-alpha.
    - Fix a denial of service attack by which any directory authority
      could crash all the others, or by which a single v2 directory
      authority could crash everybody downloading v2 directory
      information. Fixes bug 7191; bugfix on 0.2.0.10-alpha.

  o Major bugfixes (also in 0.2.3.24-rc):
    - When parsing exit policy summaries from microdescriptors, we had
      previously been ignoring the last character in each one, so that
      "accept 80,443,8080" would be treated by clients as indicating
      a node that allows access to ports 80, 443, and 808. That would
      lead to clients attempting connections that could never work,
      and ignoring exit nodes that would support their connections. Now
      clients parse these exit policy summaries correctly. Fixes bug 7192;
      bugfix on 0.2.3.1-alpha.

  o Minor bugfixes (also in 0.2.3.24-rc):
    - Clients now consider the ClientRejectInternalAddresses config option
      when using a microdescriptor consensus stanza to decide whether
      an exit relay would allow exiting to an internal address. Fixes
      bug 7190; bugfix on 0.2.3.1-alpha.

  o Minor bugfixes:
    - Only disable TLS session ticket support when running as a TLS
      server. Now clients will blend better with regular Firefox
      connections. Fixes bug 7189; bugfix on Tor 0.2.3.23-rc.

  o Code simplification and refactoring:
    - Start using OpenBSD's implementation of queue.h (originally by
      Niels Provos).
    - Move the entry node code from circuitbuild.c to its own file.
    - Move the circuit build timeout tracking code from circuitbuild.c
      to its own file.


Changes in version 0.2.3.24-rc - 2012-10-25
  Tor 0.2.3.24-rc fixes two important security vulnerabilities that
  could lead to remotely triggerable relay crashes, and fixes
  a major bug that was preventing clients from choosing suitable exit
  nodes.

  o Major bugfixes (security):
    - Fix a group of remotely triggerable assertion failures related to
      incorrect link protocol negotiation. Found, diagnosed, and fixed
      by "some guy from France". Fix for CVE-2012-2250; bugfix on
      0.2.3.6-alpha.
    - Fix a denial of service attack by which any directory authority
      could crash all the others, or by which a single v2 directory
      authority could crash everybody downloading v2 directory
      information. Fixes bug 7191; bugfix on 0.2.0.10-alpha.

  o Major bugfixes:
    - When parsing exit policy summaries from microdescriptors, we had
      previously been ignoring the last character in each one, so that
      "accept 80,443,8080" would be treated by clients as indicating
      a node that allows access to ports 80, 443, and 808. That would
      lead to clients attempting connections that could never work,
      and ignoring exit nodes that would support their connections. Now
      clients parse these exit policy summaries correctly. Fixes bug 7192;
      bugfix on 0.2.3.1-alpha.

  o Minor bugfixes:
    - Clients now consider the ClientRejectInternalAddresses config option
      when using a microdescriptor consensus stanza to decide whether
      an exit relay would allow exiting to an internal address. Fixes
      bug 7190; bugfix on 0.2.3.1-alpha.


Changes in version 0.2.4.4-alpha - 2012-10-20
  Tor 0.2.4.4-alpha adds a new v3 directory authority, fixes a privacy
  vulnerability introduced by a change in OpenSSL, fixes a remotely
  triggerable assert, and adds new channel_t and circuitmux_t abstractions
  that will make it easier to test new connection transport and cell
  scheduling algorithms.

  o New directory authorities (also in 0.2.3.23-rc):
    - Add Faravahar (run by Sina Rabbani) as the ninth v3 directory
      authority. Closes ticket 5749.

  o Major bugfixes (security/privacy, also in 0.2.3.23-rc):
    - Disable TLS session tickets. OpenSSL's implementation was giving
      our TLS session keys the lifetime of our TLS context objects, when
      perfect forward secrecy would want us to discard anything that
      could decrypt a link connection as soon as the link connection
      was closed. Fixes bug 7139; bugfix on all versions of Tor linked
      against OpenSSL 1.0.0 or later. Found by Florent Daignière.
    - Discard extraneous renegotiation attempts once the V3 link
      protocol has been initiated. Failure to do so left us open to
      a remotely triggerable assertion failure. Fixes CVE-2012-2249;
      bugfix on 0.2.3.6-alpha. Reported by "some guy from France".

  o Internal abstraction features:
    - Introduce new channel_t abstraction between circuits and
      or_connection_t to allow for implementing alternate OR-to-OR
      transports. A channel_t is an abstract object which can either be a
      cell-bearing channel, which is responsible for authenticating and
      handshaking with the remote OR and transmitting cells to and from
      it, or a listening channel, which spawns new cell-bearing channels
      at the request of remote ORs. Implements part of ticket 6465.
    - Also new is the channel_tls_t subclass of channel_t, adapting it
      to the existing or_connection_t code. The V2/V3 protocol handshaking
      code which formerly resided in command.c has been moved below the
      channel_t abstraction layer and may be found in channeltls.c now.
      Implements the rest of ticket 6465.
    - Introduce new circuitmux_t storing the queue of circuits for
      a channel; this encapsulates and abstracts the queue logic and
      circuit selection policy, and allows the latter to be overridden
      easily by switching out a policy object. The existing EWMA behavior
      is now implemented as a circuitmux_policy_t. Resolves ticket 6816.

  o Required libraries:
    - Tor now requires OpenSSL 0.9.8 or later. OpenSSL 1.0.0 or later is
      strongly recommended.

  o Minor features:
    - Warn users who run hidden services on a Tor client with
      UseEntryGuards disabled that their hidden services will be
      vulnerable to http://freehaven.net/anonbib/#hs-attack06 (the
      attack which motivated Tor to support entry guards in the first
      place). Resolves ticket 6889.
    - Tor now builds correctly on Bitrig, an OpenBSD fork. Patch from
      dhill. Resolves ticket 6982.
    - Option OutboundBindAddress can be specified multiple times and
      accepts IPv6 addresses. Resolves ticket 6876.

  o Minor bugfixes (also in 0.2.3.23-rc):
    - Don't serve or accept v2 hidden service descriptors over a
      relay's DirPort. It's never correct to do so, and disabling it
      might make it more annoying to exploit any bugs that turn up in the
      descriptor-parsing code. Fixes bug 7149.
    - Fix two cases in src/or/transports.c where we were calling
      fmt_addr() twice in a parameter list. Bug found by David
      Fifield. Fixes bug 7014; bugfix on 0.2.3.9-alpha.
    - Fix memory leaks whenever we logged any message about the "path
      bias" detection. Fixes bug 7022; bugfix on 0.2.3.21-rc.
    - When relays refuse a "create" cell because their queue of pending
      create cells is too big (typically because their cpu can't keep up
      with the arrival rate), send back reason "resource limit" rather
      than reason "internal", so network measurement scripts can get a
      more accurate picture. Fixes bug 7037; bugfix on 0.1.1.11-alpha.

  o Minor bugfixes:
    - Command-line option "--version" implies "--quiet". Fixes bug 6997.
    - Free some more still-in-use memory at exit, to make hunting for
      memory leaks easier. Resolves bug 7029.
    - When a Tor client gets a "truncated" relay cell, the first byte of
      its payload specifies why the circuit was truncated. We were
      ignoring this 'reason' byte when tearing down the circuit, resulting
      in the controller not being told why the circuit closed. Now we
      pass the reason from the truncated cell to the controller. Bugfix
      on 0.1.2.3-alpha; fixes bug 7039.
    - Downgrade "Failed to hand off onionskin" messages to "debug"
      severity, since they're typically redundant with the "Your computer
      is too slow" messages. Fixes bug 7038; bugfix on 0.2.2.16-alpha.
    - Make clients running with IPv6 bridges connect over IPv6 again,
      even without setting new config options ClientUseIPv6 and
      ClientPreferIPv6ORPort. Fixes bug 6757; bugfix on 0.2.4.1-alpha.
    - Use square brackets around IPv6 addresses in numerous places
      that needed them, including log messages, HTTPS CONNECT proxy
      requests, TransportProxy statefile entries, and pluggable transport
      extra-info lines. Fixes bug 7011; patch by David Fifield.

  o Code refactoring and cleanup:
    - Source files taken from other packages now reside in src/ext;
      previously they were scattered around the rest of Tor.
    - Avoid use of reserved identifiers in our C code. The C standard
      doesn't like us declaring anything that starts with an
      underscore, so let's knock it off before we get in trouble. Fix
      for bug 1031; bugfix on the first Tor commit.


Changes in version 0.2.3.23-rc - 2012-10-20
  Tor 0.2.3.23-rc adds a new v3 directory authority, fixes a privacy
  vulnerability introduced by a change in OpenSSL, and fixes a variety
  of smaller bugs in preparation for the release.

  o New directory authorities:
    - Add Faravahar (run by Sina Rabbani) as the ninth v3 directory
      authority. Closes ticket 5749.

  o Major bugfixes (security/privacy):
    - Disable TLS session tickets. OpenSSL's implementation was giving
      our TLS session keys the lifetime of our TLS context objects, when
      perfect forward secrecy would want us to discard anything that
      could decrypt a link connection as soon as the link connection
      was closed. Fixes bug 7139; bugfix on all versions of Tor linked
      against OpenSSL 1.0.0 or later. Found by Florent Daignière.
    - Discard extraneous renegotiation attempts once the V3 link
      protocol has been initiated. Failure to do so left us open to
      a remotely triggerable assertion failure. Fixes CVE-2012-2249;
      bugfix on 0.2.3.6-alpha. Reported by "some guy from France".

  o Major bugfixes:
    - Fix a possible crash bug when checking for deactivated circuits
      in connection_or_flush_from_first_active_circuit(). Fixes bug 6341;
      bugfix on 0.2.2.7-alpha. Bug report and fix received pseudonymously.

  o Minor bugfixes (on 0.2.3.x):
    - Fix two cases in src/or/transports.c where we were calling
      fmt_addr() twice in a parameter list. Bug found by David
      Fifield. Fixes bug 7014; bugfix on 0.2.3.9-alpha.
    - Convert an assert in the pathbias code to a log message. The assert
      appears to only be triggerable by Tor2Web mode. Fixes bug 6866;
      bugfix on 0.2.3.17-beta.
    - Fix memory leaks whenever we logged any message about the "path
      bias" detection. Fixes bug 7022; bugfix on 0.2.3.21-rc.

  o Minor bugfixes (on 0.2.2.x and earlier):
    - Don't serve or accept v2 hidden service descriptors over a relay's
      DirPort. It's never correct to do so, and disabling it might
      make it more annoying to exploit any bugs that turn up in the
      descriptor-parsing code. Fixes bug 7149.
    - When relays refuse a "create" cell because their queue of pending
      create cells is too big (typically because their cpu can't keep up
      with the arrival rate), send back reason "resource limit" rather
      than reason "internal", so network measurement scripts can get a
      more accurate picture. Bugfix on 0.1.1.11-alpha; fixes bug 7037.
    - Correct file sizes when reading binary files on Cygwin, to avoid
      a bug where Tor would fail to read its state file. Fixes bug 6844;
      bugfix on 0.1.2.7-alpha.
    - Avoid undefined behavior when parsing the list of supported
      rendezvous/introduction protocols in a hidden service descriptor.
      Previously, Tor would have confused (as-yet-unused) protocol version
      numbers greater than 32 with lower ones on many platforms. Fixes
      bug 6827; bugfix on 0.2.0.10-alpha. Found by George Kadianakis.

  o Documentation fixes:
    - Clarify that hidden services are TCP only. Fixes bug 6024.


Changes in version 0.2.4.3-alpha - 2012-09-22
  Tor 0.2.4.3-alpha fixes another opportunity for a remotely triggerable
  assertion, resumes letting relays test reachability of their DirPort,
  and cleans up a bunch of smaller bugs.

  o Security fixes:
    - Fix an assertion failure in tor_timegm() that could be triggered
      by a badly formatted directory object. Bug found by fuzzing with
      Radamsa. Fixes bug 6811; bugfix on 0.2.0.20-rc.

  o Major bugfixes:
    - Fix a possible crash bug when checking for deactivated circuits
      in connection_or_flush_from_first_active_circuit(). Fixes bug 6341;
      bugfix on 0.2.2.7-alpha. Bug report and fix received pseudonymously.
    - Allow routers to detect that their own DirPorts are running. When
      we removed support for versions_supports_begindir, we also
      accidentally removed the mechanism we used to self-test our
      DirPort. Diagnosed with help from kargig. Fixes bugs 6814 and 6815;
      bugfix on 0.2.4.2-alpha.

  o Security features:
    - Switch to a completely time-invariant approach for picking nodes
      weighted by bandwidth. Our old approach would run through the
      part of the loop after it had made its choice slightly slower
      than it ran through the part of the loop before it had made its
      choice. Addresses ticket 6538.
    - Disable the use of Guard nodes when in Tor2WebMode. Guard usage
      by tor2web clients allows hidden services to identify tor2web
      clients through their repeated selection of the same rendezvous
      and introduction point circuit endpoints (their guards). Resolves
      ticket 6888.

  o Minor features:
    - Enable Tor to read configuration, state, and key information from
      a FIFO. Previously Tor would only read from files with a positive
      stat.st_size. Code from meejah; fixes bug 6044.

  o Minor bugfixes:
    - Correct file sizes when reading binary files on Cygwin, to avoid
      a bug where Tor would fail to read its state file. Fixes bug 6844;
      bugfix on 0.1.2.7-alpha.
    - Correctly handle votes with more than 31 flags. Fixes bug 6853;
      bugfix on 0.2.0.3-alpha.
    - When complaining about a client port on a public address, log
      which address we're complaining about. Fixes bug 4020; bugfix on
      0.2.3.3-alpha. Patch by Tom Fitzhenry.
    - Convert an assert in the pathbias code to a log message. The assert
      appears to only be triggerable by Tor2Web mode. Fixes bug 6866;
      bugfix on 0.2.3.17-beta.
    - Our new buildsystem was overzealous about rebuilding manpages: it
      would rebuild them all whenever any one of them changed. Now our
      dependency checking should be correct. Fixes bug 6843; bugfix on
      0.2.4.1-alpha.
    - Don't do reachability testing over IPv6 unless AuthDirPublishIPv6
      is set. Fixes bug 6880. Bugfix on 0.2.4.1-alpha.
    - Correct log printout about which address family is preferred
      when connecting to a bridge with both an IPv4 and IPv6 OR port.
      Fixes bug 6884; bugfix on 0.2.4.1-alpha.

  o Minor bugfixes (code cleanliness):
    - Fix round_to_power_of_2() so it doesn't invoke undefined behavior
      with large values. This situation was untriggered, but nevertheless
      incorrect. Fixes bug 6831; bugfix on 0.2.0.1-alpha.
    - Reject consensus votes with more than 64 known-flags. We aren't even
      close to that limit yet, and our code doesn't handle it correctly.
      Fixes bug 6833; bugfix on 0.2.0.1-alpha.
    - Avoid undefined behavior when parsing the list of supported
      rendezvous/introduction protocols in a hidden service descriptor.
      Previously, Tor would have confused (as-yet-unused) protocol version
      numbers greater than 32 with lower ones on many platforms. Fixes
      bug 6827; bugfix on 0.2.0.10-alpha. Found by George Kadianakis.
    - Fix handling of rendezvous client authorization types over 8.
      Fixes bug 6861; bugfix on 0.2.1.5-alpha.
    - Fix building with older versions of GCC (2.95, for one) that don't
      like preprocessor directives inside macro arguments. Found by
      grarpamp. Fixes bug 6842; bugfix on 0.2.4.2-alpha.
    - Switch weighted node selection rule from using a list of doubles
      to using a list of int64_t. This change should make the process
      slightly easier to debug and maintain. Needed to finish ticket 6538.

  o Code simplification and refactoring:
    - Move the generic "config" code into a new file, and have "config.c"
      hold only torrc- and state-related code. Resolves ticket 6823.
    - Move the core of our "choose a weighted element at random" logic
      into its own function, and give it unit tests. Now the logic is
      testable, and a little less fragile too.
    - Removed the testing_since field of node_t, which hasn't been used
      for anything since 0.2.0.9-alpha.

  o Documentation fixes:
    - Clarify that hidden services are TCP only. Fixes bug 6024.
    - Resolve a typo in torrc.sample.in. Fixes bug 6819; bugfix on
      0.2.3.14-alpha.


Changes in version 0.2.3.22-rc - 2012-09-11
  Tor 0.2.3.22-rc fixes another opportunity for a remotely triggerable
  assertion.

  o Security fixes:
    - Fix an assertion failure in tor_timegm() that could be triggered
      by a badly formatted directory object. Bug found by fuzzing with
      Radamsa. Fixes bug 6811; bugfix on 0.2.0.20-rc.

  o Minor bugfixes:
    - Avoid segfault when starting up having run with an extremely old
      version of Tor and parsing its state file. Fixes bug 6801; bugfix
      on 0.2.2.23-alpha.


Changes in version 0.2.2.39 - 2012-09-11
  Tor 0.2.2.39 fixes two more opportunities for remotely triggerable
  assertions.

  o Security fixes:
    - Fix an assertion failure in tor_timegm() that could be triggered
      by a badly formatted directory object. Bug found by fuzzing with
      Radamsa. Fixes bug 6811; bugfix on 0.2.0.20-rc.
    - Do not crash when comparing an address with port value 0 to an
      address policy. This bug could have been used to cause a remote
      assertion failure by or against directory authorities, or to
      allow some applications to crash clients. Fixes bug 6690; bugfix
      on 0.2.1.10-alpha.


Changes in version 0.2.4.2-alpha - 2012-09-10
  Tor 0.2.4.2-alpha enables port forwarding for pluggable transports,
  raises the default rate limiting even more, and makes the bootstrapping
  log messages less noisy.

  o Major features:
    - Automatically forward the TCP ports of pluggable transport
      proxies using tor-fw-helper if PortForwarding is enabled. Implements
      ticket 4567.

  o Major bugfixes:
    - Raise the default BandwidthRate/BandwidthBurst values from 5MB/10MB
      to 1GB/1GB. The previous defaults were intended to be "basically
      infinite", but it turns out they're now limiting our 100mbit+
      relays and bridges. Fixes bug 6605; bugfix on 0.2.0.10-alpha (the
      last time we raised it).

  o Minor features:
    - Detect when we're running with a version of OpenSSL other than the
      one we compiled with. This has occasionally given people hard-to-
      track-down errors.
    - Log fewer lines at level "notice" about our OpenSSL and Libevent
      versions and capabilities when everything is going right. Resolves
      part of ticket 6736.
    - Directory authorities no long accept descriptors for any version of
      Tor before 0.2.2.35, or for any 0.2.3 release before 0.2.3.10-alpha.
      These versions are insecure, unsupported, or both. Implements
      ticket 6789.

  o Minor bugfixes:
    - Rename the (internal-use-only) UsingTestingNetworkDefaults option
      to start with a triple-underscore so the controller won't touch it.
      Patch by Meejah. Fixes bug 3155. Bugfix on 0.2.2.23-alpha.
    - Avoid segfault when starting up having run with an extremely old
      version of Tor and parsing its state file. Fixes bug 6801; bugfix
      on 0.2.2.23-alpha.
    - Rename the (testing-use-only) _UseFilteringSSLBufferevents option
      so it doesn't start with _. Fixes bug 3155. Bugfix on 0.2.3.1-alpha.
    - Don't follow the NULL pointer if microdescriptor generation fails.
      (This does not appear to be triggerable, but it's best to be safe.)
      Found by "f. tp.". Fixes bug 6797; bugfix on 0.2.4.1-alpha.
    - Fix mis-declared dependencies on src/common/crypto.c and
      src/or/tor_main.c that could break out-of-tree builds under some
      circumstances. Fixes bug 6778; bugfix on 0.2.4.1-alpha.
    - Avoid a warning when building common_sha1.i out of tree. Fixes bug
      6778; bugfix on 0.2.4.1-alpha.
    - Fix a harmless (in this case) build warning for implicitly
      converting a strlen() to an int. Bugfix on 0.2.4.1-alpha.

  o Removed features:
    - Now that all versions before 0.2.2.x are disallowed, we no longer
      need to work around their missing features. Thus we can remove a
      bunch of compatibility code.

  o Code refactoring:
    - Tweak tor-fw-helper to accept an arbitrary amount of arbitrary
      TCP ports to forward. In the past it only accepted two ports:
      the ORPort and the DirPort.


Changes in version 0.2.4.1-alpha - 2012-09-05
  Tor 0.2.4.1-alpha lets bridges publish their pluggable transports to
  bridgedb; lets relays use IPv6 addresses and directory authorities
  advertise them; and switches to a cleaner build interface.

  This is the first alpha release in a new series, so expect there to
  be bugs. Users who would rather test out a more stable branch should
  stay with 0.2.3.x for now.

  o Major features (bridges):
    - Bridges now report the pluggable transports they support to the
      bridge authority, so it can pass the supported transports on to
      bridgedb and/or eventually do reachability testing. Implements
      ticket 3589.

  o Major features (IPv6):
    - Bridge authorities now accept IPv6 bridge addresses and include
      them in network status documents. Implements ticket 5534.
    - Clients who set "ClientUseIPv6 1" may connect to entry nodes over
      IPv6. Set "ClientPreferIPv6ORPort 1" to make this even more likely
      to happen. Implements ticket 5535.
    - All kind of relays, not just bridges, can now advertise an IPv6
      OR port. Implements ticket 6362.
    - Directory authorities vote on IPv6 OR ports using the new consensus
      method 14. Implements ticket 6363.

  o Major features (build):
    - Switch to a nonrecursive Makefile structure. Now instead of each
      Makefile.am invoking other Makefile.am's, there is a master
      Makefile.am that includes the others. This change makes our build
      process slightly more maintainable, and improves parallelism for
      building with make -j. Original patch by Stewart Smith; various
      fixes by Jim Meyering.
    - Where available, we now use automake's "silent" make rules by
      default, so that warnings are easier to spot. You can get the old
      behavior with "make V=1". Patch by Stewart Smith for ticket 6522.

  o Minor features (code security and spec conformance):
    - Clear keys and key-derived material left on the stack in
      rendservice.c and rendclient.c. Check return value of
      crypto_pk_write_private_key_to_string() in rend_service_load_keys().
      These fixes should make us more forward-secure against cold-boot
      attacks and the like. Fixes bug 2385.
    - Reject EXTEND cells sent to nonexistent streams. According to the
      spec, an EXTEND cell sent to _any_ nonzero stream ID is invalid, but
      we were only checking for stream IDs that were currently in use.
      Found while hunting for more instances of bug 6271. Bugfix on
      0.0.2pre8, which introduced incremental circuit construction.

  o Minor features (streamlining);
    - No longer include the "opt" prefix when generating routerinfos
      or v2 directories: it has been needless since Tor 0.1.2. Closes
      ticket 5124.
    - Remove some now-needless code that tried to aggressively flush
      OR connections as data was added to them. Since 0.2.0.1-alpha, our
      cell queue logic has saved us from the failure mode that this code
      was supposed to prevent. Removing this code will limit the number
      of baroque control flow paths through Tor's network logic. Reported
      pseudonymously on IRC. Fixes bug 6468; bugfix on 0.2.0.1-alpha.

  o Minor features (controller):
    - Add a "GETINFO signal/names" control port command. Implements
      ticket 3842.
    - Provide default values for all options via "GETINFO config/defaults".
      Implements ticket 4971.

  o Minor features (IPv6):
    - New config option "AuthDirHasIPv6Connectivity 1" that directory
      authorities should set if they have IPv6 connectivity and want to
      do reachability tests for IPv6 relays. Implements feature 5974.
    - A relay with an IPv6 OR port now sends that address in NETINFO
      cells (in addition to its other address). Implements ticket 6364.

  o Minor features (log messages):
    - Omit the first heartbeat log message, because it never has anything
      useful to say, and it clutters up the bootstrapping messages.
      Resolves ticket 6758.
    - Don't log about reloading the microdescriptor cache at startup. Our
      bootstrap warnings are supposed to tell the user when there's a
      problem, and our bootstrap notices say when there isn't. Resolves
      ticket 6759; bugfix on 0.2.2.6-alpha.
    - Don't log "I learned some more directory information" when we're
      reading cached directory information. Reserve it for when new
      directory information arrives in response to a fetch. Resolves
      ticket 6760.
    - Prevent rounding error in path bias counts when scaling
      them down, and use the correct scale factor default. Also demote
      some path bias related log messages down a level and make others
      less scary sounding. Fixes bug 6647. Bugfix against 0.2.3.17-beta.
    - We no longer warn so much when generating manpages from their
      asciidoc source.

  o Code simplifications and refactoring:
    - Enhance our internal sscanf replacement so that we can eliminate
      the last remaining uses of the system sscanf. (Though those uses
      of sscanf were safe, sscanf itself is generally error prone, so
      we want to eliminate when we can.) Fixes ticket 4195 and Coverity
      CID 448.
    - Move ipv6_preferred from routerinfo_t to node_t. Addresses bug 4620.
    - Move last_reachable and testing_since from routerinfo_t to node_t.
      Implements ticket 5529.
    - Add replaycache_t structure, functions and unit tests, then refactor
      rend_service_introduce() to be more clear to read, improve, debug,
      and test. Resolves bug 6177.
    - Finally remove support for malloc_good_size and malloc_usable_size.
      We had hoped that these functions would let us eke a little more
      memory out of our malloc implementation. Unfortunately, the only
      implementations that provided these functions are also ones that
      are already efficient about not overallocation: they never got us
      more than 7 or so bytes per allocation. Removing them saves us a
      little code complexity and a nontrivial amount of build complexity.

  o New requirements:
    - Tor maintainers now require Automake version 1.9 or later to build
      Tor from the Git repository. (Automake is not required when building
      from a source distribution.)


Changes in version 0.2.3.21-rc - 2012-09-05
  Tor 0.2.3.21-rc is the fourth release candidate for the Tor 0.2.3.x
  series. It fixes a trio of potential security bugs, fixes a bug where
  we were leaving some of the fast relays out of the microdescriptor
  consensus, resumes interpreting "ORPort 0" and "DirPort 0" correctly,
  and cleans up other smaller issues.

  o Major bugfixes (security):
    - Tear down the circuit if we get an unexpected SENDME cell. Clients
      could use this trick to make their circuits receive cells faster
      than our flow control would have allowed, or to gum up the network,
      or possibly to do targeted memory denial-of-service attacks on
      entry nodes. Fixes bug 6252. Bugfix on the 54th commit on Tor --
      from July 2002, before the release of Tor 0.0.0. We had committed
      this patch previously, but we had to revert it because of bug 6271.
      Now that 6271 is fixed, this patch appears to work.
    - Reject any attempt to extend to an internal address. Without
      this fix, a router could be used to probe addresses on an internal
      network to see whether they were accepting connections. Fixes bug
      6710; bugfix on 0.0.8pre1.
    - Do not crash when comparing an address with port value 0 to an
      address policy. This bug could have been used to cause a remote
      assertion failure by or against directory authorities, or to
      allow some applications to crash clients. Fixes bug 6690; bugfix
      on 0.2.1.10-alpha.

  o Major bugfixes:
    - Remove the upper bound on microdescriptor length. We were hitting
      the limit for routers with complex exit policies or family
      declarations, causing clients to not use them. Fixes the first
      piece of bug 6404; fix on 0.2.2.6-alpha.
    - Detect "ORPort 0" as meaning, uniformly, that we're not running
      as a relay. Previously, some of our code would treat the presence
      of any ORPort line as meaning that we should act like a relay,
      even though our new listener code would correctly not open any
      ORPorts for ORPort 0. Similar bugs in other Port options are also
      fixed. Fixes the first half of bug 6507; bugfix on 0.2.3.3-alpha.

  o Minor bugfixes:
    - Avoid a pair of double-free and use-after-mark bugs that can
      occur with certain timings in canceled and re-received DNS
      requests. Fixes bug 6472; bugfix on 0.0.7rc1.
    - Fix build and 64-bit compile warnings from --enable-openbsd-malloc.
      Fixes bug 6379. Bugfix on 0.2.0.20-rc.
    - Allow one-hop directory fetching circuits the full "circuit build
      timeout" period, rather than just half of it, before failing them
      and marking the relay down. This fix should help reduce cases where
      clients declare relays (or worse, bridges) unreachable because
      the TLS handshake takes a few seconds to complete. Fixes bug 6743;
      bugfix on 0.2.2.2-alpha, where we changed the timeout from a static
      30 seconds.
    - Authorities no longer include any router in their microdescriptor
      consensuses for which they couldn't generate or agree on a
      microdescriptor. Fixes the second piece of bug 6404; fix on
      0.2.2.6-alpha.
    - Detect and reject attempts to specify both "FooPort" and
      "FooPort 0" in the same configuration domain. (It's still okay
      to have a FooPort in your configuration file, and use "FooPort 0"
      on the command line to disable it.) Fixes the second half of bug
      6507; bugfix on 0.2.3.3-alpha.
    - Make wildcarded addresses (that is, ones beginning with "*.") work
      when provided via the controller's MapAddress command. Previously,
      they were accepted, but we never actually noticed that they were
      wildcards. Fixes bug 6244; bugfix on 0.2.3.9-alpha.
    - Avoid crashing on a malformed state file where EntryGuardPathBias
      precedes EntryGuard. Fix for bug 6774; bugfix on 0.2.3.17-beta.
    - Add a (probably redundant) memory clear between iterations of
      the router status voting loop, to prevent future coding errors
      where data might leak between iterations of the loop. Resolves
      ticket 6514.

  o Minor bugfixes (log messages):
    - Downgrade "set buildtimeout to low value" messages to "info"
      severity; they were never an actual problem, there was never
      anything reasonable to do about them, and they tended to spam logs
      from time to time. Fixes bug 6251; bugfix on 0.2.2.2-alpha.
    - Downgrade path-bias warning messages to "info". We'll try to get
      them working better in 0.2.4. Add internal circuit construction
      state to protect against the noisy warn message "Unexpectedly high
      circuit_successes". Also add some additional rate-limited notice
      messages to help determine the root cause of the warn. Fixes bug
      6475. Bugfix against 0.2.3.17-beta.
    - Move log message when unable to find a microdesc in a routerstatus
      entry to parse time. Previously we'd spam this warning every time
      we tried to figure out which microdescriptors to download. Fixes
      the third piece of bug 6404; fix on 0.2.3.18-rc.

  o Minor features:
    - Consider new, removed or changed IPv6 OR ports a non-cosmetic
      change when the authority is deciding whether to accept a newly
      uploaded descriptor. Implements ticket 6423.
    - Add missing documentation for consensus and microdesc files.
      Resolves ticket 6732.


Changes in version 0.2.2.38 - 2012-08-12
  Tor 0.2.2.38 fixes a remotely triggerable crash bug, and fixes a timing
  attack that could in theory leak path information.

  o Security fixes:
    - Avoid an uninitialized memory read when reading a vote or consensus
      document that has an unrecognized flavor name. This read could
      lead to a remote crash bug. Fixes bug 6530; bugfix on 0.2.2.6-alpha.
    - Try to leak less information about what relays a client is
      choosing to a side-channel attacker. Previously, a Tor client would
      stop iterating through the list of available relays as soon as it
      had chosen one, thus finishing a little earlier when it picked
      a router earlier in the list. If an attacker can recover this
      timing information (nontrivial but not proven to be impossible),
      they could learn some coarse-grained information about which relays
      a client was picking (middle nodes in particular are likelier to
      be affected than exits). The timing attack might be mitigated by
      other factors (see bug 6537 for some discussion), but it's best
      not to take chances. Fixes bug 6537; bugfix on 0.0.8rc1.


Changes in version 0.2.3.20-rc - 2012-08-05
  Tor 0.2.3.20-rc is the third release candidate for the Tor 0.2.3.x
  series. It fixes a pair of code security bugs and a potential anonymity
  issue, updates our RPM spec files, and cleans up other smaller issues.

  o Security fixes:
    - Avoid read-from-freed-memory and double-free bugs that could occur
      when a DNS request fails while launching it. Fixes bug 6480;
      bugfix on 0.2.0.1-alpha.
    - Avoid an uninitialized memory read when reading a vote or consensus
      document that has an unrecognized flavor name. This read could
      lead to a remote crash bug. Fixes bug 6530; bugfix on 0.2.2.6-alpha.
    - Try to leak less information about what relays a client is
      choosing to a side-channel attacker. Previously, a Tor client would
      stop iterating through the list of available relays as soon as it
      had chosen one, thus finishing a little earlier when it picked
      a router earlier in the list. If an attacker can recover this
      timing information (nontrivial but not proven to be impossible),
      they could learn some coarse-grained information about which relays
      a client was picking (middle nodes in particular are likelier to
      be affected than exits). The timing attack might be mitigated by
      other factors (see bug 6537 for some discussion), but it's best
      not to take chances. Fixes bug 6537; bugfix on 0.0.8rc1.

  o Minor features:
    - Try to make the warning when giving an obsolete SOCKSListenAddress
      a little more useful.
    - Terminate active server managed proxies if Tor stops being a
      relay. Addresses parts of bug 6274; bugfix on 0.2.3.6-alpha.
    - Provide a better error message about possible OSX Asciidoc failure
      reasons. Fixes bug 6436.
    - Warn when Tor is configured to use accounting in a way that can
      link a hidden service to some other hidden service or public
      address. Resolves ticket 6490.

  o Minor bugfixes:
    - Check return value of fputs() when writing authority certificate
      file. Fixes Coverity issue 709056; bugfix on 0.2.0.1-alpha.
    - Ignore ServerTransportPlugin lines when Tor is not configured as
      a relay. Fixes bug 6274; bugfix on 0.2.3.6-alpha.
    - When disabling guards for having too high a proportion of failed
      circuits, make sure to look at each guard. Fixes bug 6397; bugfix
      on 0.2.3.17-beta.

  o Packaging (RPM):
    - Update our default RPM spec files to work with mock and rpmbuild
      on RHEL/Fedora. They have an updated set of dependencies and
      conflicts, a fix for an ancient typo when creating the "_tor"
      user, and better instructions. Thanks to Ondrej Mikle for the
      patch series. Fixes bug 6043.

  o Testing:
    - Make it possible to set the TestingTorNetwork configuration
      option using AlternateDirAuthority and AlternateBridgeAuthority
      as an alternative to setting DirServer. Addresses ticket 6377.

  o Documentation:
    - Clarify the documentation for the Alternate*Authority options.
      Fixes bug 6387.
    - Fix some typos in the manpages. Patch from A. Costa. Fixes bug 6500.

  o Code simplification and refactoring:
    - Do not use SMARTLIST_FOREACH for any loop whose body exceeds
      10 lines. Also, don't nest them. Doing so in the past has
      led to hard-to-debug code. The new style is to use the
      SMARTLIST_FOREACH_{BEGIN,END} pair. Addresses issue 6400.


Changes in version 0.2.3.19-rc - 2012-07-06
  Tor 0.2.3.19-rc is the second release candidate for the Tor 0.2.3.x
  series. It fixes the compile on Windows, reverts to a GeoIP database
  that isn't as broken, and fixes a flow control bug that has been around
  since the beginning of Tor.

  o Major bugfixes:
    - Fix a bug handling SENDME cells on nonexistent streams that could
      result in bizarre window values. Report and patch contributed
      pseudonymously. Fixes part of bug 6271. This bug was introduced
      before the first Tor release, in svn commit r152.
    - Revert to the May 1 2012 Maxmind GeoLite Country database. In the
      June 2012 database, Maxmind marked many Tor relays as country "A1",
      which will cause risky behavior for clients that set EntryNodes
      or ExitNodes. Addresses bug 6334; bugfix on 0.2.3.17-beta.
    - Instead of ENOBUFS on Windows, say WSAENOBUFS. Fixes compilation
      on Windows. Fixes bug 6296; bugfix on 0.2.3.18-rc.

  o Minor bugfixes:
    - Fix wrong TCP port range in parse_port_range(). Fixes bug 6218;
      bugfix on 0.2.1.10-alpha.


Changes in version 0.2.3.18-rc - 2012-06-28
  Tor 0.2.3.18-rc is the first release candidate for the Tor 0.2.3.x
  series. It fixes a few smaller bugs, but generally appears stable.
  Please test it and let us know whether it is!

  o Major bugfixes:
    - Allow wildcarded mapaddress targets to be specified on the
      controlport. Partially fixes bug 6244; bugfix on 0.2.3.9-alpha.
    - Make our linker option detection code more robust against linkers
      such as on FreeBSD 8, where a bad combination of options completes
      successfully but makes an unrunnable binary. Fixes bug 6173;
      bugfix on 0.2.3.17-beta.

  o Minor bugfixes (on 0.2.2.x and earlier):
    - Avoid a false positive in the util/threads unit test by increasing
      the maximum timeout time. Fixes bug 6227; bugfix on 0.2.0.4-alpha.
    - Replace "Sending publish request" log messages with "Launching
      upload", so that they no longer confusingly imply that we're
      sending something to a directory we might not even be connected
      to yet. Fixes bug 3311; bugfix on 0.2.0.10-alpha.
    - Make sure to set *socket_error in all error cases in
      connection_connect(), so it can't produce a warning about
      errno being zero from errno_to_orconn_end_reason(). Bugfix on
      0.2.1.1-alpha; resolves ticket 6028.
    - Downgrade "Got a certificate, but we already have it" log messages
      from warning to info, except when we're a dirauth. Fixes bug 5238;
      bugfix on 0.2.1.7-alpha.
    - When checking for requested signatures on the latest consensus
      before serving it to a client, make sure to check the right
      consensus flavor. Bugfix on 0.2.2.6-alpha.
    - Downgrade "eventdns rejected address" message to LOG_PROTOCOL_WARN.
      Fixes bug 5932; bugfix on 0.2.2.7-alpha.

  o Minor bugfixes (on 0.2.3.x):
    - Make format_helper_exit_status() avoid unnecessary space padding
      and stop confusing log_from_pipe(). Fixes ticket 5557; bugfix
      on 0.2.3.1-alpha.
    - Downgrade a message about cleaning the microdescriptor cache to
      "info" from "notice". Fixes bug 6238; bugfix on 0.2.3.1-alpha.
    - Log a BUG message at severity INFO if we have a networkstatus with
      a missing entry for some microdescriptor. Continues on a patch
      to 0.2.3.2-alpha.
    - Improve the log message when a managed proxy fails to launch. Fixes
      bug 5099; bugfix on 0.2.3.6-alpha.
    - Don't do DNS lookups when parsing corrupted managed proxy protocol
      messages. Fixes bug 6226; bugfix on 0.2.3.6-alpha.
    - When formatting wildcarded address mappings for the controller,
      be sure to include "*." as appropriate. Partially fixes bug 6244;
      bugfix on 0.2.3.9-alpha.
    - Avoid a warning caused by using strcspn() from glibc with clang 3.0.
      Bugfix on 0.2.3.13-alpha.
    - Stop logging messages about running with circuit timeout learning
      enabled at severity LD_BUG. Fixes bug 6169; bugfix on 0.2.3.17-beta.
    - Disable a spurious warning about reading on a marked and flushing
      connection. We shouldn't be doing that, but apparently we
      sometimes do. Fixes bug 6203; bugfix on 0.2.3.17-beta.
    - Fix a bug that stopped AllowDotExit from working on addresses
      that had an entry in the DNS cache. Fixes bug 6211; bugfix on
      0.2.3.17-beta.

  o Code simplification, refactoring, unit tests:
    - Move tor_gettimeofday_cached() into compat_libevent.c, and use
      Libevent's notion of cached time when possible.
    - Remove duplicate code for invoking getrlimit() from control.c.
    - Add a unit test for the environment_variable_names_equal function.

  o Documentation:
    - Document the --defaults-torrc option, and the new (in 0.2.3)
      semantics for overriding, extending, and clearing lists of
      options. Closes bug 4748.


Changes in version 0.2.3.17-beta - 2012-06-15
  Tor 0.2.3.17-beta enables compiler and linker hardening by default,
  gets our TLS handshake back on track for being able to blend in with
  Firefox, fixes a big bug in 0.2.3.16-alpha that broke Tor's interaction
  with Vidalia, and otherwise continues to get us closer to a release
  candidate.

  o Major features:
    - Enable gcc and ld hardening by default. Resolves ticket 5210.
    - Update TLS cipher list to match Firefox 8 and later. Resolves
      ticket 4744.
    - Implement the client side of proposal 198: remove support for
      clients falsely claiming to support standard ciphersuites that
      they can actually provide. As of modern OpenSSL versions, it's not
      necessary to fake any standard ciphersuite, and doing so prevents
      us from using better ciphersuites in the future, since servers
      can't know whether an advertised ciphersuite is really supported or
      not. Some hosts -- notably, ones with very old versions of OpenSSL
      or where OpenSSL has been built with ECC disabled -- will stand
      out because of this change; TBB users should not be affected.

  o Major bugfixes:
    - Change the default value for DynamicDHGroups (introduced in
      0.2.3.9-alpha) to 0. This feature can make Tor relays less
      identifiable by their use of the mod_ssl DH group, but at
      the cost of some usability (#4721) and bridge tracing (#6087)
      regressions. Resolves ticket 5598.
    - Send a CRLF at the end of each STATUS_* control protocol event. This
      bug tickled a bug in Vidalia which would make it freeze. Fixes
      bug 6094; bugfix on 0.2.3.16-alpha.

  o Minor bugfixes:
    - Disable writing on marked-for-close connections when they are
      blocked on bandwidth, to prevent busy-looping in Libevent. Fixes
      bug 5263; bugfix on 0.0.2pre13, where we first added a special
      case for flushing marked connections.
    - Detect SSL handshake even when the initial attempt to write the
      server hello fails. Fixes bug 4592; bugfix on 0.2.0.13-alpha.
    - Change the AllowDotExit rules so they should actually work.
      We now enforce AllowDotExit only immediately after receiving an
      address via SOCKS or DNSPort: other sources are free to provide
      .exit addresses after the resolution occurs. Fixes bug 3940;
      bugfix on 0.2.2.1-alpha.
    - Fix a (harmless) integer overflow in cell statistics reported by
      some fast relays. Fixes bug 5849; bugfix on 0.2.2.1-alpha.
    - Make sure circuitbuild.c checks LearnCircuitBuildTimeout in all the
      right places and never depends on the consensus parameters or
      computes adaptive timeouts when it is disabled. Fixes bug 5049;
      bugfix on 0.2.2.14-alpha.
    - When building Tor on Windows with -DUNICODE (not default), ensure
      that error messages, filenames, and DNS server names are always
      NUL-terminated when we convert them to a single-byte encoding.
      Fixes bug 5909; bugfix on 0.2.2.16-alpha.
    - Make Tor build correctly again with -DUNICODE -D_UNICODE defined.
      Fixes bug 6097; bugfix on 0.2.2.16-alpha.
    - Fix an edge case where TestingTorNetwork is set but the authorities
      and relays all have an uptime of zero, where the private Tor network
      could briefly lack support for hidden services. Fixes bug 3886;
      bugfix on 0.2.2.18-alpha.
    - Correct the manpage's descriptions for the default values of
      DirReqStatistics and ExtraInfoStatistics. Fixes bug 2865; bugfix
      on 0.2.3.1-alpha.
    - Fix the documentation for the --hush and --quiet command line
      options, which changed their behavior back in 0.2.3.3-alpha.
    - Fix compilation warning with clang 3.1. Fixes bug 6141; bugfix on
      0.2.3.11-alpha.

  o Minor features:
    - Rate-limit the "Weighted bandwidth is 0.000000" message, and add
      more information to it, so that we can track it down in case it
      returns again. Mitigates bug 5235.
    - Check CircuitBuildTimeout and LearnCircuitBuildTimeout in
      options_validate(); warn if LearnCircuitBuildTimeout is disabled and
      CircuitBuildTimeout is set unreasonably low. Resolves ticket 5452.
    - Warn the user when HTTPProxy, but no other proxy type, is
      configured. This can cause surprising behavior: it doesn't send
      all of Tor's traffic over the HTTPProxy -- it sends unencrypted
      directory traffic only. Resolves ticket 4663.
    - Issue a notice if a guard completes less than 40% of your circuits.
      Threshold is configurable by torrc option PathBiasNoticeRate and
      consensus parameter pb_noticepct. There is additional, off-by-
      default code to disable guards which fail too many circuits.
      Addresses ticket 5458.
    - Update to the June 6 2012 Maxmind GeoLite Country database.

  o Code simplifications and refactoring:
    - Remove validate_pluggable_transports_config(): its warning
      message is now handled by connection_or_connect().


Changes in version 0.2.2.37 - 2012-06-06
  Tor 0.2.2.37 introduces a workaround for a critical renegotiation
  bug in OpenSSL 1.0.1 (where 20% of the Tor network can't talk to itself
  currently).

  o Major bugfixes:
    - Work around a bug in OpenSSL that broke renegotiation with TLS
      1.1 and TLS 1.2. Without this workaround, all attempts to speak
      the v2 Tor connection protocol when both sides were using OpenSSL
      1.0.1 would fail. Resolves ticket 6033.
    - When waiting for a client to renegotiate, don't allow it to add
      any bytes to the input buffer. This fixes a potential DoS issue.
      Fixes bugs 5934 and 6007; bugfix on 0.2.0.20-rc.
    - Fix an edge case where if we fetch or publish a hidden service
      descriptor, we might build a 4-hop circuit and then use that circuit
      for exiting afterwards -- even if the new last hop doesn't obey our
      ExitNodes config option. Fixes bug 5283; bugfix on 0.2.0.10-alpha.

  o Minor bugfixes:
    - Fix a build warning with Clang 3.1 related to our use of vasprintf.
      Fixes bug 5969. Bugfix on 0.2.2.11-alpha.

  o Minor features:
    - Tell GCC and Clang to check for any errors in format strings passed
      to the tor_v*(print|scan)f functions.


Changes in version 0.2.3.16-alpha - 2012-06-05
  Tor 0.2.3.16-alpha introduces a workaround for a critical renegotiation
  bug in OpenSSL 1.0.1 (where 20% of the Tor network can't talk to itself
  currently). It also fixes a variety of smaller bugs and other cleanups
  that get us closer to a release candidate.

  o Major bugfixes (general):
    - Work around a bug in OpenSSL that broke renegotiation with TLS
      1.1 and TLS 1.2. Without this workaround, all attempts to speak
      the v2 Tor connection protocol when both sides were using OpenSSL
      1.0.1 would fail. Resolves ticket 6033.
    - When waiting for a client to renegotiate, don't allow it to add
      any bytes to the input buffer. This fixes a potential DoS issue.
      Fixes bugs 5934 and 6007; bugfix on 0.2.0.20-rc.
    - Pass correct OR address to managed proxies (like obfsproxy),
      even when ORListenAddress is used. Fixes bug 4865; bugfix on
      0.2.3.9-alpha.
    - The advertised platform of a router now includes only its operating
      system's name (e.g., "Linux", "Darwin", "Windows 7"), and not its
      service pack level (for Windows) or its CPU architecture (for Unix).
      We also no longer include the "git-XYZ" tag in the version. Resolves
      part of bug 2988.

  o Major bugfixes (clients):
    - If we are unable to find any exit that supports our predicted ports,
      stop calling them predicted, so that we don't loop and build
      hopeless circuits indefinitely. Fixes bug 3296; bugfix on 0.0.9pre6,
      which introduced predicted ports.
    - Fix an edge case where if we fetch or publish a hidden service
      descriptor, we might build a 4-hop circuit and then use that circuit
      for exiting afterwards -- even if the new last hop doesn't obey our
      ExitNodes config option. Fixes bug 5283; bugfix on 0.2.0.10-alpha.
    - Check at each new consensus whether our entry guards were picked
      long enough ago that we should rotate them. Previously, we only
      did this check at startup, which could lead to us holding a guard
      indefinitely. Fixes bug 5380; bugfix on 0.2.1.14-rc.
    - When fetching a bridge descriptor from a bridge authority,
      always do so anonymously, whether we have been able to open
      circuits or not. Partial fix for bug 1938; bugfix on 0.2.0.7-alpha.
      This behavior makes it *safer* to use UpdateBridgesFromAuthority,
      but we'll need to wait for bug 6010 before it's actually usable.

  o Major bugfixes (directory authorities):
    - When computing weight parameters, behave more robustly in the
      presence of a bad bwweightscale value. Previously, the authorities
      would crash if they agreed on a sufficiently broken weight_scale
      value: now, they use a reasonable default and carry on. Partial
      fix for 5786; bugfix on 0.2.2.17-alpha.
    - Check more thoroughly to prevent a rogue authority from
      double-voting on any consensus directory parameter. Previously,
      authorities would crash in this case if the total number of
      votes for any parameter exceeded the number of active voters,
      but would let it pass otherwise. Partial fix for bug 5786; bugfix
      on 0.2.2.2-alpha.

  o Minor features:
    - Rate-limit log messages when asked to connect anonymously to
      a private address. When these hit, they tended to hit fast and
      often. Also, don't bother trying to connect to addresses that we
      are sure will resolve to 127.0.0.1: getting 127.0.0.1 in a directory
      reply makes us think we have been lied to, even when the address the
      client tried to connect to was "localhost." Resolves ticket 2822.
    - Allow packagers to insert an extra string in server descriptor
      platform lines by setting the preprocessor variable TOR_BUILD_TAG.
      Resolves the rest of ticket 2988.
    - Raise the threshold of server descriptors needed (75%) and exit
      server descriptors needed (50%) before we will declare ourselves
      bootstrapped. This will make clients start building circuits a
      little later, but makes the initially constructed circuits less
      skewed and less in conflict with further directory fetches. Fixes
      ticket 3196.
    - Close any connection that sends unrecognized junk before the
      handshake. Solves an issue noted in bug 4369.
    - Improve log messages about managed transports. Resolves ticket 5070.
    - Tag a bridge's descriptor as "never to be sent unencrypted".
      This shouldn't matter, since bridges don't open non-anonymous
      connections to the bridge authority and don't allow unencrypted
      directory connections from clients, but we might as well make
      sure. Closes bug 5139.
    - Expose our view of whether we have gone dormant to the controller,
      via a new "GETINFO dormant" value. Torbutton and other controllers
      can use this to avoid doing periodic requests through Tor while
      it's dormant (bug 4718). Fixes bug 5954.
    - Tell GCC and Clang to check for any errors in format strings passed
      to the tor_v*(print|scan)f functions.
    - Update to the May 1 2012 Maxmind GeoLite Country database.

  o Minor bugfixes (already included in 0.2.2.36):
    - Reject out-of-range times like 23:59:61 in parse_rfc1123_time().
      Fixes bug 5346; bugfix on 0.0.8pre3.
    - Correct parsing of certain date types in parse_http_time().
      Without this patch, If-Modified-Since would behave
      incorrectly. Fixes bug 5346; bugfix on 0.2.0.2-alpha. Patch from
      Esteban Manchado Velázques.
    - Make our number-parsing functions always treat too-large values
      as an error, even when those values exceed the width of the
      underlying type. Previously, if the caller provided these
      functions with minima or maxima set to the extreme values of the
      underlying integer type, these functions would return those
      values on overflow rather than treating overflow as an error.
      Fixes part of bug 5786; bugfix on 0.0.9.
    - If we hit the error case where routerlist_insert() replaces an
      existing (old) server descriptor, make sure to remove that
      server descriptor from the old_routers list. Fix related to bug
      1776. Bugfix on 0.2.2.18-alpha.
    - Clarify the behavior of MaxCircuitDirtiness with hidden service
      circuits. Fixes issue 5259.

  o Minor bugfixes (coding cleanup, on 0.2.2.x and earlier):
    - Prevent a null-pointer dereference when receiving a data cell
      for a nonexistent stream when the circuit in question has an
      empty deliver window. We don't believe this is triggerable,
      since we don't currently allow deliver windows to become empty,
      but the logic is tricky enough that it's better to make the code
      robust. Fixes bug 5541; bugfix on 0.0.2pre14.
    - Fix a memory leak when trying to launch a DNS request when the
      network is disabled or the nameservers are unconfigurable. Fixes
      bug 5916; bugfix on Tor 0.1.2.1-alpha (for the unconfigurable
      nameserver case) and on 0.2.3.9-alpha (for the DisableNetwork case).
    - Don't hold a Windows file handle open for every file mapping;
      the file mapping handle is sufficient. Fixes bug 5951; bugfix on
      0.1.2.1-alpha.
    - Avoid O(n^2) performance characteristics when parsing a large
      extrainfo cache. Fixes bug 5828; bugfix on 0.2.0.1-alpha.
    - Format more doubles with %f, not %lf. Patch from grarpamp to make
      Tor build correctly on older BSDs again. Fixes bug 3894; bugfix on
      Tor 0.2.0.8-alpha.
    - Make our replacement implementation of strtok_r() compatible with
      the standard behavior of strtok_r(). Patch by nils. Fixes bug 5091;
      bugfix on 0.2.2.1-alpha.
    - Fix a NULL-pointer dereference on a badly formed
      SETCIRCUITPURPOSE command. Found by mikeyc. Fixes bug 5796;
      bugfix on 0.2.2.9-alpha.
    - Fix a build warning with Clang 3.1 related to our use of vasprintf.
      Fixes bug 5969. Bugfix on 0.2.2.11-alpha.
    - Defensively refactor rend_mid_rendezvous() so that protocol
      violations and length checks happen in the beginning. Fixes
      bug 5645.
    - Set _WIN32_WINNT to 0x0501 consistently throughout the code, so
      that IPv6 stuff will compile on MSVC, and compilation issues
      will be easier to track down. Fixes bug 5861.

  o Minor bugfixes (correctness, on 0.2.2.x and earlier):
    - Exit nodes now correctly report EADDRINUSE and EADDRNOTAVAIL as
      resource exhaustion, so that clients can adjust their load to
      try other exits. Fixes bug 4710; bugfix on 0.1.0.1-rc, which
      started using END_STREAM_REASON_RESOURCELIMIT.
    - Don't check for whether the address we're using for outbound
      connections has changed until after the outbound connection has
      completed. On Windows, getsockname() doesn't succeed until the
      connection is finished. Fixes bug 5374; bugfix on 0.1.1.14-alpha.
    - If the configuration tries to set MyFamily on a bridge, refuse to
      do so, and warn about the security implications. Fixes bug 4657;
      bugfix on 0.2.0.3-alpha.
    - If the client fails to set a reasonable set of ciphersuites
      during its v2 handshake renegotiation, allow the renegotiation to
      continue nevertheless (i.e. send all the required certificates).
      Fixes bug 4591; bugfix on 0.2.0.20-rc.
    - When we receive a SIGHUP and the controller __ReloadTorrcOnSIGHUP
      option is set to 0 (which Vidalia version 0.2.16 now does when
      a SAVECONF attempt fails), perform other actions that SIGHUP
      usually causes (like reopening the logs). Fixes bug 5095; bugfix
      on 0.2.1.9-alpha.
    - If we fail to write a microdescriptor to the disk cache, do not
      continue replacing the old microdescriptor file. Fixes bug 2954;
      bugfix on 0.2.2.6-alpha.
    - Exit nodes don't need to fetch certificates for authorities that
      they don't recognize; only directory authorities, bridges,
      and caches need to do that. Fixes part of bug 2297; bugfix on
      0.2.2.11-alpha.
    - Correctly handle checking the permissions on the parent
      directory of a control socket in the root directory. Bug found
      by Esteban Manchado Velázquez. Fixes bug 5089; bugfix on Tor
      0.2.2.26-beta.
    - When told to add a bridge with the same digest as a preexisting
      bridge but a different addr:port, change the addr:port as
      requested. Previously we would not notice the change. Fixes half
      of bug 5603; fix on 0.2.2.26-beta.
    - End AUTHCHALLENGE error messages (in the control protocol) with
      a CRLF. Fixes bug 5760; bugfix on 0.2.2.36 and 0.2.3.13-alpha.

  o Minor bugfixes (on 0.2.3.x):
    - Turn an assertion (that the number of handshakes received as a
      server is not < 1) into a warning. Fixes bug 4873; bugfix on
      0.2.3.1-alpha.
    - Format IPv4 addresses correctly in ADDRMAP events. (Previously,
      we had reversed them when the answer was cached.) Fixes bug
      5723; bugfix on 0.2.3.1-alpha.
    - Work correctly on Linux systems with accept4 support advertised in
      their headers, but without accept4 support in the kernel. Fix
      by murb. Fixes bug 5762; bugfix on 0.2.3.1-alpha.
    - When told to add a bridge with the same addr:port as a preexisting
      bridge but a different transport, change the transport as
      requested. Previously we would not notice the change. Fixes half
      of bug 5603; fix on 0.2.3.2-alpha.
    - Avoid a "double-reply" warning when replying to a SOCKS request
      with a parse error. Patch from Fabian Keil. Fixes bug 4108;
      bugfix on 0.2.3.4-alpha.
    - Fix a bug where a bridge authority crashes if it has seen no
      directory requests when it's time to write statistics to disk.
      Fixes bug 5891; bugfix on 0.2.3.6-alpha. Also fixes bug 5508 in
      a better way.
    - Don't try to open non-control listeners when DisableNetwork is set.
      Previously, we'd open all listeners, then immediately close them.
      Fixes bug 5604; bugfix on 0.2.3.9-alpha.
    - Don't abort the managed proxy protocol if the managed proxy
      sends us an unrecognized line; ignore it instead. Fixes bug
      5910; bugfix on 0.2.3.9-alpha.
    - Fix a compile warning in crypto.c when compiling with clang 3.1.
      Fixes bug 5969, bugfix on 0.2.3.9-alpha.
    - Fix a compilation issue on GNU Hurd, which doesn't have PATH_MAX.
      Fixes bug 5355; bugfix on 0.2.3.11-alpha.
    - Remove bogus definition of "_WIN32" from src/win32/orconfig.h, to
      unbreak the MSVC build. Fixes bug 5858; bugfix on 0.2.3.12-alpha.
    - Resolve numerous small warnings and build issues with MSVC. Resolves
      bug 5859.

  o Documentation fixes:
    - Improve the manual's documentation for the NT Service command-line
      options. Addresses ticket 3964.
    - Clarify SessionGroup documentation slightly; resolves ticket 5437.
    - Document the changes to the ORPort and DirPort options, and the
      fact that {OR/Dir}ListenAddress is now unnecessary (and
      therefore deprecated). Resolves ticket 5597.

  o Removed files:
    - Remove the torrc.bridge file: we don't use it for anything, and
      it had become badly desynchronized from torrc.sample. Resolves
      bug 5622.


Changes in version 0.2.2.36 - 2012-05-24
  Tor 0.2.2.36 updates the addresses for two of the eight directory
  authorities, fixes some potential anonymity and security issues,
  and fixes several crash bugs.

  Tor 0.2.1.x has reached its end-of-life. Those Tor versions have many
  known flaws, and nobody should be using them. You should upgrade. If
  you're using a Linux or BSD and its packages are obsolete, stop using
  those packages and upgrade anyway.

  o Directory authority changes:
    - Change IP address for maatuska (v3 directory authority).
    - Change IP address for ides (v3 directory authority), and rename
      it to turtles.

  o Security fixes:
    - When building or running with any version of OpenSSL earlier
      than 0.9.8s or 1.0.0f, disable SSLv3 support. These OpenSSL
      versions have a bug (CVE-2011-4576) in which their block cipher
      padding includes uninitialized data, potentially leaking sensitive
      information to any peer with whom they make a SSLv3 connection. Tor
      does not use SSL v3 by default, but a hostile client or server
      could force an SSLv3 connection in order to gain information that
      they shouldn't have been able to get. The best solution here is to
      upgrade to OpenSSL 0.9.8s or 1.0.0f (or later). But when building
      or running with a non-upgraded OpenSSL, we disable SSLv3 entirely
      to make sure that the bug can't happen.
    - Never use a bridge or a controller-supplied node as an exit, even
      if its exit policy allows it. Found by wanoskarnet. Fixes bug
      5342. Bugfix on 0.1.1.15-rc (for controller-purpose descriptors)
      and 0.2.0.3-alpha (for bridge-purpose descriptors).
    - Only build circuits if we have a sufficient threshold of the total
      descriptors that are marked in the consensus with the "Exit"
      flag. This mitigates an attack proposed by wanoskarnet, in which
      all of a client's bridges collude to restrict the exit nodes that
      the client knows about. Fixes bug 5343.
    - Provide controllers with a safer way to implement the cookie
      authentication mechanism. With the old method, if another locally
      running program could convince a controller that it was the Tor
      process, then that program could trick the controller into telling
      it the contents of an arbitrary 32-byte file. The new "SAFECOOKIE"
      authentication method uses a challenge-response approach to prevent
      this attack. Fixes bug 5185; implements proposal 193.

  o Major bugfixes:
    - Avoid logging uninitialized data when unable to decode a hidden
      service descriptor cookie. Fixes bug 5647; bugfix on 0.2.1.5-alpha.
    - Avoid a client-side assertion failure when receiving an INTRODUCE2
      cell on a general purpose circuit. Fixes bug 5644; bugfix on
      0.2.1.6-alpha.
    - Fix builds when the path to sed, openssl, or sha1sum contains
      spaces, which is pretty common on Windows. Fixes bug 5065; bugfix
      on 0.2.2.1-alpha.
    - Correct our replacements for the timeradd() and timersub() functions
      on platforms that lack them (for example, Windows). The timersub()
      function is used when expiring circuits, while timeradd() is
      currently unused. Bug report and patch by Vektor. Fixes bug 4778;
      bugfix on 0.2.2.24-alpha.
    - Fix the SOCKET_OK test that we use to tell when socket
      creation fails so that it works on Win64. Fixes part of bug 4533;
      bugfix on 0.2.2.29-beta. Bug found by wanoskarnet.

  o Minor bugfixes:
    - Reject out-of-range times like 23:59:61 in parse_rfc1123_time().
      Fixes bug 5346; bugfix on 0.0.8pre3.
    - Make our number-parsing functions always treat too-large values
      as an error, even when those values exceed the width of the
      underlying type. Previously, if the caller provided these
      functions with minima or maxima set to the extreme values of the
      underlying integer type, these functions would return those
      values on overflow rather than treating overflow as an error.
      Fixes part of bug 5786; bugfix on 0.0.9.
    - Older Linux kernels erroneously respond to strange nmap behavior
      by having accept() return successfully with a zero-length
      socket. When this happens, just close the connection. Previously,
      we would try harder to learn the remote address: but there was
      no such remote address to learn, and our method for trying to
      learn it was incorrect. Fixes bugs 1240, 4745, and 4747. Bugfix
      on 0.1.0.3-rc. Reported and diagnosed by "r1eo".
    - Correct parsing of certain date types in parse_http_time().
      Without this patch, If-Modified-Since would behave
      incorrectly. Fixes bug 5346; bugfix on 0.2.0.2-alpha. Patch from
      Esteban Manchado Velázques.
    - Change the BridgePassword feature (part of the "bridge community"
      design, which is not yet implemented) to use a time-independent
      comparison. The old behavior might have allowed an adversary
      to use timing to guess the BridgePassword value. Fixes bug 5543;
      bugfix on 0.2.0.14-alpha.
    - Detect and reject certain misformed escape sequences in
      configuration values. Previously, these values would cause us
      to crash if received in a torrc file or over an authenticated
      control port. Bug found by Esteban Manchado Velázquez, and
      independently by Robert Connolly from Matta Consulting who further
      noted that it allows a post-authentication heap overflow. Patch
      by Alexander Schrijver. Fixes bugs 5090 and 5402 (CVE 2012-1668);
      bugfix on 0.2.0.16-alpha.
    - Fix a compile warning when using the --enable-openbsd-malloc
      configure option. Fixes bug 5340; bugfix on 0.2.0.20-rc.
    - During configure, detect when we're building with clang version
      3.0 or lower and disable the -Wnormalized=id and -Woverride-init
      CFLAGS. clang doesn't support them yet.
    - When sending an HTTP/1.1 proxy request, include a Host header.
      Fixes bug 5593; bugfix on 0.2.2.1-alpha.
    - Fix a NULL-pointer dereference on a badly formed SETCIRCUITPURPOSE
      command. Found by mikeyc. Fixes bug 5796; bugfix on 0.2.2.9-alpha.
    - If we hit the error case where routerlist_insert() replaces an
      existing (old) server descriptor, make sure to remove that
      server descriptor from the old_routers list. Fix related to bug
      1776. Bugfix on 0.2.2.18-alpha.

  o Minor bugfixes (documentation and log messages):
    - Fix a typo in a log message in rend_service_rendezvous_has_opened().
      Fixes bug 4856; bugfix on Tor 0.0.6.
    - Update "ClientOnly" man page entry to explain that there isn't
      really any point to messing with it. Resolves ticket 5005.
    - Document the GiveGuardFlagTo_CVE_2011_2768_VulnerableRelays
      directory authority option (introduced in Tor 0.2.2.34).
    - Downgrade the "We're missing a certificate" message from notice
      to info: people kept mistaking it for a real problem, whereas it
      is seldom the problem even when we are failing to bootstrap. Fixes
      bug 5067; bugfix on 0.2.0.10-alpha.
    - Correctly spell "connect" in a log message on failure to create a
      controlsocket. Fixes bug 4803; bugfix on 0.2.2.26-beta.
    - Clarify the behavior of MaxCircuitDirtiness with hidden service
      circuits. Fixes issue 5259.

  o Minor features:
    - Directory authorities now reject versions of Tor older than
      0.2.1.30, and Tor versions between 0.2.2.1-alpha and 0.2.2.20-alpha
      inclusive. These versions accounted for only a small fraction of
      the Tor network, and have numerous known security issues. Resolves
      issue 4788.
    - Update to the May 1 2012 Maxmind GeoLite Country database.

  o Feature removal:
    - When sending or relaying a RELAY_EARLY cell, we used to convert
      it to a RELAY cell if the connection was using the v1 link
      protocol. This was a workaround for older versions of Tor, which
      didn't handle RELAY_EARLY cells properly. Now that all supported
      versions can handle RELAY_EARLY cells, and now that we're enforcing
      the "no RELAY_EXTEND commands except in RELAY_EARLY cells" rule,
      remove this workaround. Addresses bug 4786.


Changes in version 0.2.3.15-alpha - 2012-04-30
  Tor 0.2.3.15-alpha fixes a variety of smaller bugs, including making
  the development branch build on Windows again.

  o Minor bugfixes (on 0.2.2.x and earlier):
    - Make sure that there are no unhandled pending TLS errors before
      reading from a TLS stream. We had checks in 0.1.0.3-rc, but
      lost them in 0.1.0.5-rc when we refactored read_to_buf_tls().
      Bugfix on 0.1.0.5-rc; fixes bug 4528.
    - Fix an assert that directory authorities could trigger on sighup
      during some configuration state transitions. We now don't treat
      it as a fatal error when the new descriptor we just generated in
      init_keys() isn't accepted. Fixes bug 4438; bugfix on 0.2.1.9-alpha.
    - After we pick a directory mirror, we would refuse to use it if
      it's in our ExcludeExitNodes list, resulting in mysterious failures
      to bootstrap for people who just wanted to avoid exiting from
      certain locations. Fixes bug 5623; bugfix on 0.2.2.25-alpha.
    - When building with --enable-static-tor on OpenBSD, do not
      erroneously attempt to link -lrt. Fixes bug 5103.

  o Minor bugfixes (on 0.2.3.x):
    - When Tor is built with kernel headers from a recent (last few
      years) Linux kernel, do not fail to run on older (pre-2.6.28
      Linux kernels). Fixes bug 5112; bugfix on 0.2.3.1-alpha.
    - Fix cross-compilation issues with mingw. Bugfixes on 0.2.3.6-alpha
      and 0.2.3.12-alpha.
    - Fix compilation with miniupnpc version 1.6; patch from
      Anthony G. Basile. Fixes bug 5434; bugfix on 0.2.3.12-alpha.
    - Fix compilation with MSVC, which had defined MS_WINDOWS. Bugfix
      on 0.2.3.13-alpha; found and fixed by Gisle Vanem.
    - Fix compilation on platforms without unistd.h, or where environ
      is defined in stdlib.h. Fixes bug 5704; bugfix on 0.2.3.13-alpha.

  o Minor features:
    - Directory authorities are now a little more lenient at accepting
      older router descriptors, or newer router descriptors that don't
      make big changes. This should help ameliorate past and future
      issues where routers think they have uploaded valid descriptors,
      but the authorities don't think so. Fix for ticket 2479.
    - Make the code that clients use to detect an address change be
      IPv6-aware, so that it won't fill clients' logs with error
      messages when trying to get the IPv4 address of an IPv6
      connection. Implements ticket 5537.

  o Removed features:
    - Remove the GiveGuardFlagTo_CVE_2011_2768_VulnerableRelays option;
      authorities needed to use it for a while to keep the network working
      as people upgraded to 0.2.1.31, 0.2.2.34, or 0.2.3.6-alpha, but
      that was six months ago. As of now, it should no longer be needed
      or used.


Changes in version 0.2.3.14-alpha - 2012-04-23
  Tor 0.2.3.14-alpha fixes yet more bugs to get us closer to a release
  candidate. It also dramatically speeds up AES: fast relays should
  consider switching to the newer OpenSSL library.

  o Directory authority changes:
    - Change IP address for ides (v3 directory authority), and rename
      it to turtles.

  o Major bugfixes:
    - Avoid logging uninitialized data when unable to decode a hidden
      service descriptor cookie. Fixes bug 5647; bugfix on 0.2.1.5-alpha.
    - Avoid a client-side assertion failure when receiving an INTRODUCE2
      cell on a general purpose circuit. Fixes bug 5644; bugfix on
      0.2.1.6-alpha.
    - If authorities are unable to get a v2 consensus document from other
      directory authorities, they no longer fall back to fetching
      them from regular directory caches. Fixes bug 5635; bugfix on
      0.2.2.26-beta, where routers stopped downloading v2 consensus
      documents entirely.
    - When we start a Tor client with a normal consensus already cached,
      be willing to download a microdescriptor consensus. Fixes bug 4011;
      fix on 0.2.3.1-alpha.

  o Major features (performance):
    - When built to use OpenSSL 1.0.1, and built for an x86 or x86_64
      instruction set, take advantage of OpenSSL's AESNI, bitsliced, or
      vectorized AES implementations as appropriate. These can be much,
      much faster than other AES implementations.

  o Minor bugfixes (0.2.2.x and earlier):
    - Don't launch more than 10 service-side introduction-point circuits
      for a hidden service in five minutes. Previously, we would consider
      launching more introduction-point circuits if at least one second
      had passed without any introduction-point circuits failing. Fixes
      bug 4607; bugfix on 0.0.7pre1.
    - Change the BridgePassword feature (part of the "bridge community"
      design, which is not yet implemented) to use a time-independent
      comparison. The old behavior might have allowed an adversary
      to use timing to guess the BridgePassword value. Fixes bug 5543;
      bugfix on 0.2.0.14-alpha.
    - Enforce correct return behavior of tor_vsscanf() when the '%%'
      pattern is used. Fixes bug 5558. Bugfix on 0.2.1.13.
    - When sending an HTTP/1.1 proxy request, include a Host header.
      Fixes bug 5593; bugfix on 0.2.2.1-alpha.
    - Don't log that we have "decided to publish new relay descriptor"
      unless we are actually publishing a descriptor. Fixes bug 3942;
      bugfix on 0.2.2.28-beta.

  o Minor bugfixes (0.2.3.x):
    - Fix a bug where a bridge authority crashes (on a failed assert)
      if it has seen no directory requests when it's time to write
      statistics to disk. Fixes bug 5508. Bugfix on 0.2.3.6-alpha.
    - Fix bug stomping on ORPort option NoListen and ignoring option
      NoAdvertise. Fixes bug 5151; bugfix on 0.2.3.9-alpha.
    - In the testsuite, provide a large enough buffer in the tor_sscanf
      unit test. Otherwise we'd overrun that buffer and crash during
      the unit tests. Found by weasel. Fixes bug 5449; bugfix on
      0.2.3.12-alpha.
    - Make sure we create the keys directory if it doesn't exist and we're
      about to store the dynamic Diffie-Hellman parameters. Fixes bug
      5572; bugfix on 0.2.3.13-alpha.
    - Fix a small memory leak when trying to decode incorrect base16
      authenticator during SAFECOOKIE authentication. Found by
      Coverity Scan. Fixes CID 507. Bugfix on 0.2.3.13-alpha.

  o Minor features:
    - Add more information to a log statement that might help track down
      bug 4091. If you're seeing "Bug: tor_addr_is_internal() called with a
      non-IP address" messages (or any Bug messages, for that matter!),
      please let us know about it.
    - Relays now understand an IPv6 address when they get one from a
      directory server. Resolves ticket 4875.
    - Resolve IPv6 addresses in bridge and entry statistics to country
      code "??" which means we at least count them. Resolves ticket 5053;
      improves on 0.2.3.9-alpha.
    - Update to the April 3 2012 Maxmind GeoLite Country database.
    - Begin a doc/state-contents.txt file to explain the contents of
      the Tor state file. Fixes bug 2987.

  o Default torrc changes:
    - Stop listing "socksport 9050" in torrc.sample. We open a socks
      port on 9050 by default anyway, so this should not change anything
      in practice.
    - Stop mentioning the deprecated *ListenAddress options in
      torrc.sample. Fixes bug 5438.
    - Document unit of bandwidth related options in sample torrc.
      Fixes bug 5621.

  o Removed features:
    - The "torify" script no longer supports the "tsocks" socksifier
      tool, since tsocks doesn't support DNS and UDP right for Tor.
      Everyone should be using torsocks instead. Fixes bugs 3530 and
      5180. Based on a patch by "ugh".

  o Code refactoring:
    - Change the symmetric cipher interface so that creating and
      initializing a stream cipher are no longer separate functions.
    - Remove all internal support for unpadded RSA. We never used it, and
      it would be a bad idea to start.


Changes in version 0.2.3.13-alpha - 2012-03-26
  Tor 0.2.3.13-alpha fixes a variety of stability and correctness bugs
  in managed pluggable transports, as well as providing other cleanups
  that get us closer to a release candidate.

  o Directory authority changes:
    - Change IP address for maatuska (v3 directory authority).

  o Security fixes:
    - Provide controllers with a safer way to implement the cookie
      authentication mechanism. With the old method, if another locally
      running program could convince a controller that it was the Tor
      process, then that program could trick the controller into telling
      it the contents of an arbitrary 32-byte file. The new "SAFECOOKIE"
      authentication method uses a challenge-response approach to prevent
      this attack. Fixes bug 5185, implements proposal 193.
    - Never use a bridge or a controller-supplied node as an exit, even
      if its exit policy allows it. Found by wanoskarnet. Fixes bug
      5342. Bugfix on 0.1.1.15-rc (for controller-purpose descriptors)
      and 0.2.0.3-alpha (for bridge-purpose descriptors).
    - Only build circuits if we have a sufficient threshold of the total
      descriptors that are marked in the consensus with the "Exit"
      flag. This mitigates an attack proposed by wanoskarnet, in which
      all of a client's bridges collude to restrict the exit nodes that
      the client knows about. Fixes bug 5343.

  o Major bugfixes (on Tor 0.2.3.x):
    - Avoid an assert when managed proxies like obfsproxy are configured,
      and we receive HUP signals or setconf attempts too rapidly. This
      situation happens most commonly when Vidalia tries to attach to
      Tor or tries to configure the Tor it's attached to. Fixes bug 5084;
      bugfix on 0.2.3.6-alpha.
    - Fix a relay-side pluggable transports bug where managed proxies were
      unreachable from the Internet, because Tor asked them to bind on
      localhost. Fixes bug 4725; bugfix on 0.2.3.9-alpha.
    - Stop discarding command-line arguments when TestingTorNetwork
      is set. Discovered by Kevin Bauer. Fixes bug 5373; bugfix on
      0.2.3.9-alpha, where task 4552 added support for two layers of
      torrc files.
    - Resume allowing the unit tests to run in gdb. This was accidentally
      made impossible when the DisableDebuggerAttachment option was
      introduced. Fixes bug 5448; bugfix on 0.2.3.9-alpha.
    - Resume building with nat-pmp support. Fixes bug 4955; bugfix on
      0.2.3.11-alpha. Reported by Anthony G. Basile.

  o Minor bugfixes (on 0.2.2.x and earlier):
    - Ensure we don't cannibalize circuits that are longer than three hops
      already, so we don't end up making circuits with 5 or more
      hops. Patch contributed by wanoskarnet. Fixes bug 5231; bugfix on
      0.1.0.1-rc which introduced cannibalization.
    - Detect and reject certain misformed escape sequences in
      configuration values. Previously, these values would cause us
      to crash if received in a torrc file or over an authenticated
      control port. Bug found by Esteban Manchado Velázquez, and
      independently by Robert Connolly from Matta Consulting who further
      noted that it allows a post-authentication heap overflow. Patch
      by Alexander Schrijver. Fixes bugs 5090 and 5402 (CVE 2012-1668);
      bugfix on 0.2.0.16-alpha.
    - Fix a compile warning when using the --enable-openbsd-malloc
      configure option. Fixes bug 5340; bugfix on 0.2.0.20-rc.
    - Directory caches no longer refuse to clean out descriptors because
      of missing v2 networkstatus documents, unless they're configured
      to retrieve v2 networkstatus documents. Fixes bug 4838; bugfix on
      0.2.2.26-beta. Patch by Daniel Bryg.
    - Update to the latest version of the tinytest unit testing framework.
      This includes a couple of bugfixes that can be relevant for
      running forked unit tests on Windows, and removes all reserved
      identifiers.

  o Minor bugfixes (on 0.2.3.x):
    - On a failed pipe() call, don't leak file descriptors. Fixes bug
      4296; bugfix on 0.2.3.1-alpha.
    - Spec conformance: on a v3 handshake, do not send a NETINFO cell
      until after we have received a CERTS cell. Fixes bug 4361; bugfix
      on 0.2.3.6-alpha. Patch by "frosty".
    - When binding to an IPv6 address, set the IPV6_V6ONLY socket
      option, so that the IP stack doesn't decide to use it for IPv4
      too. Fixes bug 4760; bugfix on 0.2.3.9-alpha.
    - Ensure that variables set in Tor's environment cannot override
      environment variables that Tor passes to a managed
      pluggable-transport proxy. Previously, Tor would pass every
      variable in its environment to managed proxies along with the new
      ones, in such a way that on many operating systems, the inherited
      environment variables would override those which Tor tried to
      explicitly set. Bugfix on 0.2.3.12-alpha for most Unixoid systems;
      bugfix on 0.2.3.9-alpha for Windows.

  o Minor features:
    - A wide variety of new unit tests by Esteban Manchado Velázquez.
    - Shorten links in the tor-exit-notice file. Patch by Christian Kujau.
    - Update to the March 6 2012 Maxmind GeoLite Country database.


Changes in version 0.2.3.12-alpha - 2012-02-13
  Tor 0.2.3.12-alpha lets fast exit relays scale better, allows clients
  to use bridges that run Tor 0.2.2.x, and resolves several big bugs
  when Tor is configured to use a pluggable transport like obfsproxy.

  o Major bugfixes:
    - Fix builds when the path to sed, openssl, or sha1sum contains
      spaces, which is pretty common on Windows. Fixes bug 5065; bugfix
      on 0.2.2.1-alpha.
    - Set the SO_REUSEADDR socket option before we call bind() on outgoing
      connections. This change should allow busy exit relays to stop
      running out of available sockets as quickly. Fixes bug 4950;
      bugfix on 0.2.2.26-beta.
    - Allow 0.2.3.x clients to use 0.2.2.x bridges. Previously the client
      would ask the bridge for microdescriptors, which are only supported
      in 0.2.3.x, and then fail to bootstrap when it didn't get the
      answers it wanted. Fixes bug 4013; bugfix on 0.2.3.2-alpha.
    - Properly set up obfsproxy's environment when in managed mode. The
      Tor Browser Bundle needs LD_LIBRARY_PATH to be passed to obfsproxy,
      and when you run your Tor as a daemon, there's no HOME. Fixes bugs
      5076 and 5082; bugfix on 0.2.3.6-alpha.

  o Minor features:
    - Use the dead_strip option when building Tor on OS X. This reduces
      binary size by almost 19% when linking openssl and libevent
      statically, which we do for Tor Browser Bundle.
    - Fix broken URLs in the sample torrc file, and tell readers about
      the OutboundBindAddress, ExitPolicyRejectPrivate, and
      PublishServerDescriptor options. Addresses bug 4652.
    - Update to the February 7 2012 Maxmind GeoLite Country database.

  o Minor bugfixes:
    - Downgrade the "We're missing a certificate" message from notice
      to info: people kept mistaking it for a real problem, whereas it
      is seldom the problem even when we are failing to bootstrap. Fixes
      bug 5067; bugfix on 0.2.0.10-alpha.
    - Don't put "TOR_PT_EXTENDED_SERVER_PORT=127.0.0.1:4200" in a
      managed pluggable transport server proxy's environment.
      Previously, we would put it there, even though Tor doesn't
      implement an 'extended server port' yet, and even though Tor
      almost certainly isn't listening at that address. For now, we set
      it to an empty string to avoid crashing older obfsproxies. Bugfix
      on 0.2.3.6-alpha.
    - Log the heartbeat message every HeartbeatPeriod seconds, not every
      HeartbeatPeriod + 1 seconds. Fixes bug 4942; bugfix on
      0.2.3.1-alpha. Bug reported by Scott Bennett.
    - Calculate absolute paths correctly on Windows. Fixes bug 4973;
      bugfix on 0.2.3.11-alpha.
    - Update "ClientOnly" man page entry to explain that there isn't
      really any point to messing with it. Resolves ticket 5005.
    - Use the correct CVE number for CVE-2011-4576 in our comments and
      log messages. Found by "fermenthor". Resolves bug 5066; bugfix on
      0.2.3.11-alpha.

  o Code simplifications and refactoring:
    - Use the _WIN32 macro throughout our code to detect Windows.
      (Previously we had used the obsolete 'WIN32' and the idiosyncratic
      'MS_WINDOWS'.)


Changes in version 0.2.3.11-alpha - 2012-01-22
  Tor 0.2.3.11-alpha marks feature-freeze for the 0.2.3 tree. It deploys
  the last step of the plan to limit maximum circuit length, includes
  a wide variety of hidden service performance and correctness fixes,
  works around an OpenSSL security flaw if your distro is too stubborn
  to upgrade, and fixes a bunch of smaller issues.

  o Major features:
    - Now that Tor 0.2.0.x is completely deprecated, enable the final
      part of "Proposal 110: Avoiding infinite length circuits" by
      refusing all circuit-extend requests that do not use a relay_early
      cell. This change helps Tor resist a class of denial-of-service
      attacks by limiting the maximum circuit length.
    - Adjust the number of introduction points that a hidden service
      will try to maintain based on how long its introduction points
      remain in use and how many introductions they handle. Fixes
      part of bug 3825.
    - Try to use system facilities for enumerating local interface
      addresses, before falling back to our old approach (which was
      binding a UDP socket, and calling getsockname() on it). That
      approach was scaring OS X users whose draconian firewall
      software warned about binding to UDP sockets, regardless of
      whether packets were sent. Now we try to use getifaddrs(),
      SIOCGIFCONF, or GetAdaptersAddresses(), depending on what the
      system supports. Resolves ticket 1827.

  o Major security workaround:
    - When building or running with any version of OpenSSL earlier
      than 0.9.8s or 1.0.0f, disable SSLv3 support. These OpenSSL
      versions have a bug (CVE-2011-4576) in which their block cipher
      padding includes uninitialized data, potentially leaking sensitive
      information to any peer with whom they make a SSLv3 connection. Tor
      does not use SSL v3 by default, but a hostile client or server
      could force an SSLv3 connection in order to gain information that
      they shouldn't have been able to get. The best solution here is to
      upgrade to OpenSSL 0.9.8s or 1.0.0f (or later). But when building
      or running with a non-upgraded OpenSSL, we disable SSLv3 entirely
      to make sure that the bug can't happen.

  o Major bugfixes:
    - Fix the SOCKET_OK test that we use to tell when socket
      creation fails so that it works on Win64. Fixes part of bug 4533;
      bugfix on 0.2.2.29-beta. Bug found by wanoskarnet.
    - Correct our replacements for the timeradd() and timersub() functions
      on platforms that lack them (for example, Windows). The timersub()
      function is used when expiring circuits, while timeradd() is
      currently unused. Bug report and patch by Vektor. Fixes bug 4778;
      bugfix on 0.2.2.24-alpha and 0.2.3.1-alpha.
    - Do not use OpenSSL 1.0.0's counter mode: it has a critical bug
      that was fixed in OpenSSL 1.0.0a. We test for the counter mode
      bug at runtime, not compile time, because some distributions hack
      their OpenSSL to mis-report its version. Fixes bug 4779; bugfix
      on 0.2.3.9-alpha. Found by Pascal.

  o Minor features (controller):
    - Use absolute path names when reporting the torrc filename in the
      control protocol, so a controller can more easily find the torrc
      file. Resolves bug 1101.
    - Extend the control protocol to report flags that control a circuit's
      path selection in CIRC events and in replies to 'GETINFO
      circuit-status'. Implements part of ticket 2411.
    - Extend the control protocol to report the hidden service address
      and current state of a hidden-service-related circuit in CIRC
      events and in replies to 'GETINFO circuit-status'. Implements part
      of ticket 2411.
    - When reporting the path to the cookie file to the controller,
      give an absolute path. Resolves ticket 4881.
    - Allow controllers to request an event notification whenever a
      circuit is cannibalized or its purpose is changed. Implements
      part of ticket 3457.
    - Include the creation time of a circuit in CIRC and CIRC2
      control-port events and the list produced by the 'GETINFO
      circuit-status' control-port command.

  o Minor features (directory authorities):
    - Directory authorities now reject versions of Tor older than
      0.2.1.30, and Tor versions between 0.2.2.1-alpha and 0.2.2.20-alpha
      inclusive. These versions accounted for only a small fraction of
      the Tor network, and have numerous known security issues. Resolves
      issue 4788.
    - Authority operators can now vote for all relays in a given
      set of countries to be BadDir/BadExit/Invalid/Rejected.
    - Provide two consensus parameters (FastFlagMinThreshold and
      FastFlagMaxThreshold) to control the range of allowable bandwidths
      for the Fast directory flag. These allow authorities to run
      experiments on appropriate requirements for being a "Fast" node.
      The AuthDirFastGuarantee config value still applies. Implements
      ticket 3946.
    - Document the GiveGuardFlagTo_CVE_2011_2768_VulnerableRelays
      directory authority option (introduced in Tor 0.2.2.34).

  o Minor features (other):
    - Don't disable the DirPort when we cannot exceed our AccountingMax
      limit during this interval because the effective bandwidthrate is
      low enough. This is useful in a situation where AccountMax is only
      used as an additional safeguard or to provide statistics.
    - Prepend an informative header to generated dynamic_dh_params files.
    - If EntryNodes are given, but UseEntryGuards is set to 0, warn that
      EntryNodes will have no effect. Resolves issue 2571.
    - Log more useful messages when we fail to disable debugger
      attachment.
    - Log which authority we're missing votes from when we go to fetch
      them from the other auths.
    - Log (at debug level) whenever a circuit's purpose is changed.
    - Add missing documentation for the MaxClientCircuitsPending,
      UseMicrodescriptors, UserspaceIOCPBuffers, and
      _UseFilteringSSLBufferevents options, all introduced during
      the 0.2.3.x series.
    - Update to the January 3 2012 Maxmind GeoLite Country database.

  o Minor bugfixes (hidden services):
    - Don't close hidden service client circuits which have almost
      finished connecting to their destination when they reach
      the normal circuit-build timeout. Previously, we would close
      introduction circuits which are waiting for an acknowledgement
      from the introduction point, and rendezvous circuits which have
      been specified in an INTRODUCE1 cell sent to a hidden service,
      after the normal CBT. Now, we mark them as 'timed out', and launch
      another rendezvous attempt in parallel. This behavior change can
      be disabled using the new CloseHSClientCircuitsImmediatelyOnTimeout
      option. Fixes part of bug 1297; bugfix on 0.2.2.2-alpha.
    - Don't close hidden-service-side rendezvous circuits when they
      reach the normal circuit-build timeout. This behavior change can
      be disabled using the new
      CloseHSServiceRendCircuitsImmediatelyOnTimeout option. Fixes the
      remaining part of bug 1297; bugfix on 0.2.2.2-alpha.
    - Make sure we never mark the wrong rendezvous circuit as having
      had its introduction cell acknowledged by the introduction-point
      relay. Previously, when we received an INTRODUCE_ACK cell on a
      client-side hidden-service introduction circuit, we might have
      marked a rendezvous circuit other than the one we specified in
      the INTRODUCE1 cell as INTRO_ACKED, which would have produced
      a warning message and interfered with the hidden service
      connection-establishment process. Fixes bug 4759; bugfix on
      0.2.3.3-alpha, when we added the stream-isolation feature which
      might cause Tor to open multiple rendezvous circuits for the same
      hidden service.
    - Don't trigger an assertion failure when we mark a new client-side
      hidden-service introduction circuit for close during the process
      of creating it. Fixes bug 4796; bugfix on 0.2.3.6-alpha. Reported
      by murb.

  o Minor bugfixes (log messages):
    - Correctly spell "connect" in a log message on failure to create a
      controlsocket. Fixes bug 4803; bugfix on 0.2.2.26-beta and
      0.2.3.2-alpha.
    - Fix a typo in a log message in rend_service_rendezvous_has_opened().
      Fixes bug 4856; bugfix on Tor 0.0.6.
    - Fix the log message describing how we work around discovering
      that our version is the ill-fated OpenSSL 0.9.8l. Fixes bug
      4837; bugfix on 0.2.2.9-alpha.
    - When logging about a disallowed .exit name, do not also call it
      an "invalid onion address". Fixes bug 3325; bugfix on 0.2.2.9-alpha.

  o Minor bugfixes (build fixes):
    - During configure, detect when we're building with clang version
      3.0 or lower and disable the -Wnormalized=id and -Woverride-init
      CFLAGS. clang doesn't support them yet.
    - During configure, search for library containing cos function as
      libm lives in libcore on some platforms (BeOS/Haiku). Linking
      against libm was hard-coded before. Fixes the first part of bug
      4727; bugfix on 0.2.2.2-alpha. Patch and analysis by Martin Hebnes
      Pedersen.
    - Detect attempts to build Tor on (as yet hypothetical) versions
      of Windows where sizeof(intptr_t) != sizeof(SOCKET). Partial
      fix for bug 4533. Bugfix on 0.2.2.28-beta.
    - Preprocessor directives should not be put inside the arguments
      of a macro. This would break compilation with GCC releases prior
      to version 3.3. We would never recommend such an old GCC version,
      but it is apparently required for binary compatibility on some
      platforms (namely, certain builds of Haiku). Fixes the other part
      of bug 4727; bugfix on 0.2.3.3-alpha. Patch and analysis by Martin
      Hebnes Pedersen.

  o Minor bugfixes (other):
    - Older Linux kernels erroneously respond to strange nmap behavior
      by having accept() return successfully with a zero-length
      socket. When this happens, just close the connection. Previously,
      we would try harder to learn the remote address: but there was
      no such remote address to learn, and our method for trying to
      learn it was incorrect. Fixes bugs 1240, 4745, and 4747. Bugfix
      on 0.1.0.3-rc. Reported and diagnosed by "r1eo".
    - Fix null-pointer access that could occur if TLS allocation failed.
      Fixes bug 4531; bugfix on 0.2.0.20-rc. Found by "troll_un". This was
      erroneously listed as fixed in 0.2.3.9-alpha, but the fix had
      accidentally been reverted.
    - Fix our implementation of crypto_random_hostname() so it can't
      overflow on ridiculously large inputs. (No Tor version has ever
      provided this kind of bad inputs, but let's be correct in depth.)
      Fixes bug 4413; bugfix on 0.2.2.9-alpha. Fix by Stephen Palmateer.
    - Find more places in the code that should have been testing for
      invalid sockets using the SOCKET_OK macro. Required for a fix
      for bug 4533. Bugfix on 0.2.2.28-beta.
    - Fix an assertion failure when, while running with bufferevents, a
      connection finishes connecting after it is marked for close, but
      before it is closed. Fixes bug 4697; bugfix on 0.2.3.1-alpha.
    - test_util_spawn_background_ok() hardcoded the expected value
      for ENOENT to 2. This isn't portable as error numbers are
      platform specific, and particularly the hurd has ENOENT at
      0x40000002. Construct expected string at runtime, using the correct
      value for ENOENT. Fixes bug 4733; bugfix on 0.2.3.1-alpha.
    - Reject attempts to disable DisableDebuggerAttachment while Tor is
      running. Fixes bug 4650; bugfix on 0.2.3.9-alpha.
    - Use an appropriate-width type for sockets in tor-fw-helper on
      win64. Fixes bug 1983 at last. Bugfix on 0.2.3.9-alpha.

  o Feature removal:
    - When sending or relaying a RELAY_EARLY cell, we used to convert
      it to a RELAY cell if the connection was using the v1 link
      protocol. This was a workaround for older versions of Tor, which
      didn't handle RELAY_EARLY cells properly. Now that all supported
      versions can handle RELAY_EARLY cells, and now that we're enforcing
      the "no RELAY_EXTEND commands except in RELAY_EARLY cells" rule,
      remove this workaround. Addresses bug 4786.

  o Code simplifications and refactoring:
    - Use OpenSSL's built-in SSL_state_string_long() instead of our
      own homebrewed ssl_state_to_string() replacement. Patch from
      Emile Snyder. Fixes bug 4653.
    - Use macros to indicate OpenSSL versions, so we don't need to worry
      about accidental hexadecimal bit shifts.
    - Remove some workaround code for OpenSSL 0.9.6 (which is no longer
      supported).
    - Convert more instances of tor_snprintf+tor_strdup into tor_asprintf.
    - Use the smartlist_add_asprintf() alias more consistently.
    - Use a TOR_INVALID_SOCKET macro when initializing a socket to an
      invalid value, rather than just -1.
    - Rename a handful of old identifiers, mostly related to crypto
      structures and crypto functions. By convention, our "create an
      object" functions are called "type_new()", our "free an object"
      functions are called "type_free()", and our types indicate that
      they are types only with a final "_t". But a handful of older
      types and functions broke these rules, with function names like
      "type_create" or "subsystem_op_type", or with type names like
      type_env_t.


Changes in version 0.2.3.10-alpha - 2011-12-16
  Tor 0.2.3.10-alpha fixes a critical heap-overflow security issue in
  Tor's buffers code. Absolutely everybody should upgrade.

  The bug relied on an incorrect calculation when making data continuous
  in one of our IO buffers, if the first chunk of the buffer was
  misaligned by just the wrong amount. The miscalculation would allow an
  attacker to overflow a piece of heap-allocated memory. To mount this
  attack, the attacker would need to either open a SOCKS connection to
  Tor's SocksPort (usually restricted to localhost), or target a Tor
  instance configured to make its connections through a SOCKS proxy
  (which Tor does not do by default).

  Good security practice requires that all heap-overflow bugs should be
  presumed to be exploitable until proven otherwise, so we are treating
  this as a potential code execution attack. Please upgrade immediately!
  This bug does not affect bufferevents-based builds of Tor. Special
  thanks to "Vektor" for reporting this issue to us!

  This release also contains a few minor bugfixes for issues discovered
  in 0.2.3.9-alpha.

  o Major bugfixes:
    - Fix a heap overflow bug that could occur when trying to pull
      data into the first chunk of a buffer, when that chunk had
      already had some data drained from it. Fixes CVE-2011-2778;
      bugfix on 0.2.0.16-alpha. Reported by "Vektor".

  o Minor bugfixes:
    - If we can't attach streams to a rendezvous circuit when we
      finish connecting to a hidden service, clear the rendezvous
      circuit's stream-isolation state and try to attach streams
      again. Previously, we cleared rendezvous circuits' isolation
      state either too early (if they were freshly built) or not at all
      (if they had been built earlier and were cannibalized). Bugfix on
      0.2.3.3-alpha; fixes bug 4655.
    - Fix compilation of the libnatpmp helper on non-Windows. Bugfix on
      0.2.3.9-alpha; fixes bug 4691. Reported by Anthony G. Basile.
    - Fix an assertion failure when a relay with accounting enabled
      starts up while dormant. Fixes bug 4702; bugfix on 0.2.3.9-alpha.

  o Minor features:
    - Update to the December 6 2011 Maxmind GeoLite Country database.


Changes in version 0.2.2.35 - 2011-12-16
  Tor 0.2.2.35 fixes a critical heap-overflow security issue in Tor's
  buffers code. Absolutely everybody should upgrade.

  The bug relied on an incorrect calculation when making data continuous
  in one of our IO buffers, if the first chunk of the buffer was
  misaligned by just the wrong amount. The miscalculation would allow an
  attacker to overflow a piece of heap-allocated memory. To mount this
  attack, the attacker would need to either open a SOCKS connection to
  Tor's SocksPort (usually restricted to localhost), or target a Tor
  instance configured to make its connections through a SOCKS proxy
  (which Tor does not do by default).

  Good security practice requires that all heap-overflow bugs should be
  presumed to be exploitable until proven otherwise, so we are treating
  this as a potential code execution attack. Please upgrade immediately!
  This bug does not affect bufferevents-based builds of Tor. Special
  thanks to "Vektor" for reporting this issue to us!

  Tor 0.2.2.35 also fixes several bugs in previous versions, including
  crash bugs for unusual configurations, and a long-term bug that
  would prevent Tor from starting on Windows machines with draconian
  AV software.

  With this release, we remind everyone that 0.2.0.x has reached its
  formal end-of-life. Those Tor versions have many known flaws, and
  nobody should be using them. You should upgrade -- ideally to the
  0.2.2.x series. If you're using a Linux or BSD and its packages are
  obsolete, stop using those packages and upgrade anyway.

  The Tor 0.2.1.x series is also approaching its end-of-life: it will no
  longer receive support after some time in early 2012.

  o Major bugfixes:
    - Fix a heap overflow bug that could occur when trying to pull
      data into the first chunk of a buffer, when that chunk had
      already had some data drained from it. Fixes CVE-2011-2778;
      bugfix on 0.2.0.16-alpha. Reported by "Vektor".
    - Initialize Libevent with the EVENT_BASE_FLAG_NOLOCK flag enabled, so
      that it doesn't attempt to allocate a socketpair. This could cause
      some problems on Windows systems with overzealous firewalls. Fix for
      bug 4457; workaround for Libevent versions 2.0.1-alpha through
      2.0.15-stable.
    - If we mark an OR connection for close based on a cell we process,
      don't process any further cells on it. We already avoid further
      reads on marked-for-close connections, but now we also discard the
      cells we'd already read. Fixes bug 4299; bugfix on 0.2.0.10-alpha,
      which was the first version where we might mark a connection for
      close based on processing a cell on it.
    - Correctly sanity-check that we don't underflow on a memory
      allocation (and then assert) for hidden service introduction
      point decryption. Bug discovered by Dan Rosenberg. Fixes bug 4410;
      bugfix on 0.2.1.5-alpha.
    - Fix a memory leak when we check whether a hidden service
      descriptor has any usable introduction points left. Fixes bug
      4424. Bugfix on 0.2.2.25-alpha.
    - Don't crash when we're running as a relay and don't have a GeoIP
      file. Bugfix on 0.2.2.34; fixes bug 4340. This backports a fix
      we've had in the 0.2.3.x branch already.
    - When running as a client, do not print a misleading (and plain
      wrong) log message that we're collecting "directory request"
      statistics: clients don't collect statistics. Also don't create a
      useless (because empty) stats file in the stats/ directory. Fixes
      bug 4353; bugfix on 0.2.2.34.

  o Minor bugfixes:
    - Detect failure to initialize Libevent. This fix provides better
      detection for future instances of bug 4457.
    - Avoid frequent calls to the fairly expensive cull_wedged_cpuworkers
      function. This was eating up hideously large amounts of time on some
      busy servers. Fixes bug 4518; bugfix on 0.0.9.8.
    - Resolve an integer overflow bug in smartlist_ensure_capacity().
      Fixes bug 4230; bugfix on Tor 0.1.0.1-rc. Based on a patch by
      Mansour Moufid.
    - Don't warn about unused log_mutex in log.c when building with
      --disable-threads using a recent GCC. Fixes bug 4437; bugfix on
      0.1.0.6-rc which introduced --disable-threads.
    - When configuring, starting, or stopping an NT service, stop
      immediately after the service configuration attempt has succeeded
      or failed. Fixes bug 3963; bugfix on 0.2.0.7-alpha.
    - When sending a NETINFO cell, include the original address
      received for the other side, not its canonical address. Found
      by "troll_un"; fixes bug 4349; bugfix on 0.2.0.10-alpha.
    - Fix a typo in a hibernation-related log message. Fixes bug 4331;
      bugfix on 0.2.2.23-alpha; found by "tmpname0901".
    - Fix a memory leak in launch_direct_bridge_descriptor_fetch() that
      occurred when a client tried to fetch a descriptor for a bridge
      in ExcludeNodes. Fixes bug 4383; bugfix on 0.2.2.25-alpha.
    - Backport fixes for a pair of compilation warnings on Windows.
      Fixes bug 4521; bugfix on 0.2.2.28-beta and on 0.2.2.29-beta.
    - If we had ever tried to call tor_addr_to_str on an address of
      unknown type, we would have done a strdup on an uninitialized
      buffer. Now we won't. Fixes bug 4529; bugfix on 0.2.1.3-alpha.
      Reported by "troll_un".
    - Correctly detect and handle transient lookup failures from
      tor_addr_lookup. Fixes bug 4530; bugfix on 0.2.1.5-alpha.
      Reported by "troll_un".
    - Fix null-pointer access that could occur if TLS allocation failed.
      Fixes bug 4531; bugfix on 0.2.0.20-rc. Found by "troll_un".
    - Use tor_socket_t type for listener argument to accept(). Fixes bug
      4535; bugfix on 0.2.2.28-beta. Found by "troll_un".

  o Minor features:
    - Add two new config options for directory authorities:
      AuthDirFastGuarantee sets a bandwidth threshold for guaranteeing the
      Fast flag, and AuthDirGuardBWGuarantee sets a bandwidth threshold
      that is always sufficient to satisfy the bandwidth requirement for
      the Guard flag. Now it will be easier for researchers to simulate
      Tor networks with different values. Resolves ticket 4484.
    - When Tor ignores a hidden service specified in its configuration,
      include the hidden service's directory in the warning message.
      Previously, we would only tell the user that some hidden service
      was ignored. Bugfix on 0.0.6; fixes bug 4426.
    - Update to the December 6 2011 Maxmind GeoLite Country database.

  o Packaging changes:
    - Make it easier to automate expert package builds on Windows,
      by removing an absolute path from makensis.exe command.


Changes in version 0.2.1.32 - 2011-12-16
  Tor 0.2.1.32 backports important security and privacy fixes for
  oldstable. This release is intended only for package maintainers and
  others who cannot use the 0.2.2 stable series. All others should be
  using Tor 0.2.2.x or newer.

  The Tor 0.2.1.x series will reach formal end-of-life some time in
  early 2012; we will stop releasing patches for it then.

  o Major bugfixes (also included in 0.2.2.x):
    - Correctly sanity-check that we don't underflow on a memory
      allocation (and then assert) for hidden service introduction
      point decryption. Bug discovered by Dan Rosenberg. Fixes bug 4410;
      bugfix on 0.2.1.5-alpha.
    - Fix a heap overflow bug that could occur when trying to pull
      data into the first chunk of a buffer, when that chunk had
      already had some data drained from it. Fixes CVE-2011-2778;
      bugfix on 0.2.0.16-alpha. Reported by "Vektor".

  o Minor features:
    - Update to the December 6 2011 Maxmind GeoLite Country database.


Changes in version 0.2.3.9-alpha - 2011-12-08
  Tor 0.2.3.9-alpha introduces initial IPv6 support for bridges, adds
  a "DisableNetwork" security feature that bundles can use to avoid
  touching the network until bridges are configured, moves forward on
  the pluggable transport design, fixes a flaw in the hidden service
  design that unnecessarily prevented clients with wrong clocks from
  reaching hidden services, and fixes a wide variety of other issues.

  o Major features:
    - Clients can now connect to private bridges over IPv6. Bridges
      still need at least one IPv4 address in order to connect to
      other relays. Note that we don't yet handle the case where the
      user has two bridge lines for the same bridge (one IPv4, one
      IPv6). Implements parts of proposal 186.
    - New "DisableNetwork" config option to prevent Tor from launching any
      connections or accepting any connections except on a control port.
      Bundles and controllers can set this option before letting Tor talk
      to the rest of the network, for example to prevent any connections
      to a non-bridge address. Packages like Orbot can also use this
      option to instruct Tor to save power when the network is off.
    - Clients and bridges can now be configured to use a separate
      "transport" proxy. This approach makes the censorship arms race
      easier by allowing bridges to use protocol obfuscation plugins. It
      implements the "managed proxy" part of proposal 180 (ticket 3472).
    - When using OpenSSL 1.0.0 or later, use OpenSSL's counter mode
      implementation. It makes AES_CTR about 7% faster than our old one
      (which was about 10% faster than the one OpenSSL used to provide).
      Resolves ticket 4526.
    - Add a "tor2web mode" for clients that want to connect to hidden
      services non-anonymously (and possibly more quickly). As a safety
      measure to try to keep users from turning this on without knowing
      what they are doing, tor2web mode must be explicitly enabled at
      compile time, and a copy of Tor compiled to run in tor2web mode
      cannot be used as a normal Tor client. Implements feature 2553.
    - Add experimental support for running on Windows with IOCP and no
      kernel-space socket buffers. This feature is controlled by a new
      "UserspaceIOCPBuffers" config option (off by default), which has
      no effect unless Tor has been built with support for bufferevents,
      is running on Windows, and has enabled IOCP. This may, in the long
      run, help solve or mitigate bug 98.
    - Use a more secure consensus parameter voting algorithm. Now at
      least three directory authorities or a majority of them must
      vote on a given parameter before it will be included in the
      consensus. Implements proposal 178.

  o Major bugfixes:
    - Hidden services now ignore the timestamps on INTRODUCE2 cells.
      They used to check that the timestamp was within 30 minutes
      of their system clock, so they could cap the size of their
      replay-detection cache, but that approach unnecessarily refused
      service to clients with wrong clocks. Bugfix on 0.2.1.6-alpha, when
      the v3 intro-point protocol (the first one which sent a timestamp
      field in the INTRODUCE2 cell) was introduced; fixes bug 3460.
    - Only use the EVP interface when AES acceleration is enabled,
      to avoid a 5-7% performance regression. Resolves issue 4525;
      bugfix on 0.2.3.8-alpha.

  o Privacy/anonymity features (bridge detection):
    - Make bridge SSL certificates a bit more stealthy by using random
      serial numbers, in the same fashion as OpenSSL when generating
      self-signed certificates. Implements ticket 4584.
    - Introduce a new config option "DynamicDHGroups", enabled by
      default, which provides each bridge with a unique prime DH modulus
      to be used during SSL handshakes. This option attempts to help
      against censors who might use the Apache DH modulus as a static
      identifier for bridges. Addresses ticket 4548.

  o Minor features (new/different config options):
    - New configuration option "DisableDebuggerAttachment" (on by default)
      to prevent basic debugging attachment attempts by other processes.
      Supports Mac OS X and Gnu/Linux. Resolves ticket 3313.
    - Allow MapAddress directives to specify matches against super-domains,
      as in "MapAddress *.torproject.org *.torproject.org.torserver.exit".
      Implements issue 933.
    - Slightly change behavior of "list" options (that is, config
      options that can appear more than once) when they appear both in
      torrc and on the command line. Previously, the command-line options
      would be appended to the ones from torrc. Now, the command-line
      options override the torrc options entirely. This new behavior
      allows the user to override list options (like exit policies and
      ports to listen on) from the command line, rather than simply
      appending to the list.
    - You can get the old (appending) command-line behavior for "list"
      options by prefixing the option name with a "+".
    - You can remove all the values for a "list" option from the command
      line without adding any new ones by prefixing the option name
      with a "/".
    - Add experimental support for a "defaults" torrc file to be parsed
      before the regular torrc. Torrc options override the defaults file's
      options in the same way that the command line overrides the torrc.
      The SAVECONF controller command saves only those options which
      differ between the current configuration and the defaults file. HUP
      reloads both files. (Note: This is an experimental feature; its
      behavior will probably be refined in future 0.2.3.x-alpha versions
      to better meet packagers' needs.) Implements task 4552.

  o Minor features:
    - Try to make the introductory warning message that Tor prints on
      startup more useful for actually finding help and information.
      Resolves ticket 2474.
    - Running "make version" now displays the version of Tor that
      we're about to build. Idea from katmagic; resolves issue 4400.
    - Expire old or over-used hidden service introduction points.
      Required by fix for bug 3460.
    - Move the replay-detection cache for the RSA-encrypted parts of
      INTRODUCE2 cells to the introduction point data structures.
      Previously, we would use one replay-detection cache per hidden
      service. Required by fix for bug 3460.
    - Reduce the lifetime of elements of hidden services' Diffie-Hellman
      public key replay-detection cache from 60 minutes to 5 minutes. This
      replay-detection cache is now used only to detect multiple
      INTRODUCE2 cells specifying the same rendezvous point, so we can
      avoid launching multiple simultaneous attempts to connect to it.

  o Minor bugfixes (on Tor 0.2.2.x and earlier):
    - Resolve an integer overflow bug in smartlist_ensure_capacity().
      Fixes bug 4230; bugfix on Tor 0.1.0.1-rc. Based on a patch by
      Mansour Moufid.
    - Fix a minor formatting issue in one of tor-gencert's error messages.
      Fixes bug 4574.
    - Prevent a false positive from the check-spaces script, by disabling
      the "whitespace between function name and (" check for functions
      named 'op()'.
    - Fix a log message suggesting that people contact a non-existent
      email address. Fixes bug 3448.
    - Fix null-pointer access that could occur if TLS allocation failed.
      Fixes bug 4531; bugfix on 0.2.0.20-rc. Found by "troll_un".
    - Report a real bootstrap problem to the controller on router
      identity mismatch. Previously we just said "foo", which probably
      made a lot of sense at the time. Fixes bug 4169; bugfix on
      0.2.1.1-alpha.
    - If we had ever tried to call tor_addr_to_str() on an address of
      unknown type, we would have done a strdup() on an uninitialized
      buffer. Now we won't. Fixes bug 4529; bugfix on 0.2.1.3-alpha.
      Reported by "troll_un".
    - Correctly detect and handle transient lookup failures from
      tor_addr_lookup(). Fixes bug 4530; bugfix on 0.2.1.5-alpha.
      Reported by "troll_un".
    - Use tor_socket_t type for listener argument to accept(). Fixes bug
      4535; bugfix on 0.2.2.28-beta. Found by "troll_un".
    - Initialize conn->addr to a valid state in spawn_cpuworker(). Fixes
      bug 4532; found by "troll_un".

  o Minor bugfixes (on Tor 0.2.3.x):
    - Fix a compile warning in tor_inet_pton(). Bugfix on 0.2.3.8-alpha;
      fixes bug 4554.
    - Don't send two ESTABLISH_RENDEZVOUS cells when opening a new
      circuit for use as a hidden service client's rendezvous point.
      Fixes bugs 4641 and 4171; bugfix on 0.2.3.3-alpha. Diagnosed
      with help from wanoskarnet.
    - Restore behavior of overriding SocksPort, ORPort, and similar
      options from the command line. Bugfix on 0.2.3.3-alpha.

  o Build fixes:
    - Properly handle the case where the build-tree is not the same
      as the source tree when generating src/common/common_sha1.i,
      src/or/micro-revision.i, and src/or/or_sha1.i. Fixes bug 3953;
      bugfix on 0.2.0.1-alpha.

  o Code simplifications, cleanups, and refactorings:
    - Remove the pure attribute from all functions that used it
      previously. In many cases we assigned it incorrectly, because the
      functions might assert or call impure functions, and we don't have
      evidence that keeping the pure attribute is worthwhile. Implements
      changes suggested in ticket 4421.
    - Remove some dead code spotted by coverity. Fixes cid 432.
      Bugfix on 0.2.3.1-alpha, closes bug 4637.


Changes in version 0.2.3.8-alpha - 2011-11-22
  Tor 0.2.3.8-alpha fixes some crash and assert bugs, including a
  socketpair-related bug that has been bothering Windows users. It adds
  support to serve microdescriptors to controllers, so Vidalia's network
  map can resume listing relays (once Vidalia implements its side),
  and adds better support for hardware AES acceleration. Finally, it
  starts the process of adjusting the bandwidth cutoff for getting the
  "Fast" flag from 20KB to (currently) 32KB -- preliminary results show
  that tiny relays harm performance more than they help network capacity.

  o Major bugfixes:
    - Initialize Libevent with the EVENT_BASE_FLAG_NOLOCK flag enabled, so
      that it doesn't attempt to allocate a socketpair. This could cause
      some problems on Windows systems with overzealous firewalls. Fix for
      bug 4457; workaround for Libevent versions 2.0.1-alpha through
      2.0.15-stable.
    - Correctly sanity-check that we don't underflow on a memory
      allocation (and then assert) for hidden service introduction
      point decryption. Bug discovered by Dan Rosenberg. Fixes bug 4410;
      bugfix on 0.2.1.5-alpha.
    - Remove the artificially low cutoff of 20KB to guarantee the Fast
      flag. In the past few years the average relay speed has picked
      up, and while the "top 7/8 of the network get the Fast flag" and
      "all relays with 20KB or more of capacity get the Fast flag" rules
      used to have the same result, now the top 7/8 of the network has
      a capacity more like 32KB. Bugfix on 0.2.1.14-rc. Fixes bug 4489.
    - Fix a rare assertion failure when checking whether a v0 hidden
      service descriptor has any usable introduction points left, and
      we don't have enough information to build a circuit to the first
      intro point named in the descriptor. The HS client code in
      0.2.3.x no longer uses v0 HS descriptors, but this assertion can
      trigger on (and crash) v0 HS authorities. Fixes bug 4411.
      Bugfix on 0.2.3.1-alpha; diagnosed by frosty_un.
    - Make bridge authorities not crash when they are asked for their own
      descriptor. Bugfix on 0.2.3.7-alpha, reported by Lucky Green.
    - When running as a client, do not print a misleading (and plain
      wrong) log message that we're collecting "directory request"
      statistics: clients don't collect statistics. Also don't create a
      useless (because empty) stats file in the stats/ directory. Fixes
      bug 4353; bugfix on 0.2.2.34 and 0.2.3.7-alpha.

  o Major features:
    - Allow Tor controllers like Vidalia to obtain the microdescriptor
      for a relay by identity digest or nickname. Previously,
      microdescriptors were only available by their own digests, so a
      controller would have to ask for and parse the whole microdescriptor
      consensus in order to look up a single relay's microdesc. Fixes
      bug 3832; bugfix on 0.2.3.1-alpha.
    - Use OpenSSL's EVP interface for AES encryption, so that all AES
      operations can use hardware acceleration (if present). Resolves
      ticket 4442.

  o Minor bugfixes (on 0.2.2.x and earlier):
    - Detect failure to initialize Libevent. This fix provides better
      detection for future instances of bug 4457.
    - Avoid frequent calls to the fairly expensive cull_wedged_cpuworkers
      function. This was eating up hideously large amounts of time on some
      busy servers. Fixes bug 4518; bugfix on 0.0.9.8.
    - Don't warn about unused log_mutex in log.c when building with
      --disable-threads using a recent GCC. Fixes bug 4437; bugfix on
      0.1.0.6-rc which introduced --disable-threads.
    - Allow manual 'authenticate' commands to the controller interface
      from netcat (nc) as well as telnet. We were rejecting them because
      they didn't come with the expected whitespace at the end of the
      command. Bugfix on 0.1.1.1-alpha; fixes bug 2893.
    - Fix some (not actually triggerable) buffer size checks in usage of
      tor_inet_ntop. Fixes bug 4434; bugfix on Tor 0.2.0.1-alpha. Patch
      by Anders Sundman.
    - Fix parsing of some corner-cases with tor_inet_pton(). Fixes
      bug 4515; bugfix on 0.2.0.1-alpha; fix by Anders Sundman.
    - When configuring, starting, or stopping an NT service, stop
      immediately after the service configuration attempt has succeeded
      or failed. Fixes bug 3963; bugfix on 0.2.0.7-alpha.
    - When sending a NETINFO cell, include the original address
      received for the other side, not its canonical address. Found
      by "troll_un"; fixes bug 4349; bugfix on 0.2.0.10-alpha.
    - Rename the bench_{aes,dmap} functions to test_*, so that tinytest
      can pick them up when the tests aren't disabled. Bugfix on
      0.2.2.4-alpha which introduced tinytest.
    - Fix a memory leak when we check whether a hidden service
      descriptor has any usable introduction points left. Fixes bug
      4424. Bugfix on 0.2.2.25-alpha.
    - Fix a memory leak in launch_direct_bridge_descriptor_fetch() that
      occurred when a client tried to fetch a descriptor for a bridge
      in ExcludeNodes. Fixes bug 4383; bugfix on 0.2.2.25-alpha.

  o Minor bugfixes (on 0.2.3.x):
    - Make util unit tests build correctly with MSVC. Bugfix on
      0.2.3.3-alpha. Patch by Gisle Vanem.
    - Successfully detect AUTH_CHALLENGE cells with no recognized
      authentication type listed. Fixes bug 4367; bugfix on 0.2.3.6-alpha.
      Found by frosty_un.
    - If a relay receives an AUTH_CHALLENGE cell it can't answer,
      it should still send a NETINFO cell to allow the connection to
      become open. Fixes bug 4368; fix on 0.2.3.6-alpha; bug found by
      "frosty".
    - Log less loudly when we get an invalid authentication certificate
      from a source other than a directory authority: it's not unusual
      to see invalid certs because of clock skew. Fixes bug 4370; bugfix
      on 0.2.3.6-alpha.
    - Tolerate servers with more clock skew in their authentication
      certificates than previously. Fixes bug 4371; bugfix on
      0.2.3.6-alpha.
    - Fix a couple of compile warnings on Windows. Fixes bug 4469; bugfix
      on 0.2.3.4-alpha and 0.2.3.6-alpha.

  o Minor features:
    - Add two new config options for directory authorities:
      AuthDirFastGuarantee sets a bandwidth threshold for guaranteeing the
      Fast flag, and AuthDirGuardBWGuarantee sets a bandwidth threshold
      that is always sufficient to satisfy the bandwidth requirement for
      the Guard flag. Now it will be easier for researchers to simulate
      Tor networks with different values. Resolves ticket 4484.
    - When Tor ignores a hidden service specified in its configuration,
      include the hidden service's directory in the warning message.
      Previously, we would only tell the user that some hidden service
      was ignored. Bugfix on 0.0.6; fixes bug 4426.
    - When we fail to initialize Libevent, retry with IOCP disabled so we
      don't need to turn on multi-threading support in Libevent, which in
      turn requires a working socketpair(). This is a workaround for bug
      4457, which affects Libevent versions from 2.0.1-alpha through
      2.0.15-stable.
    - Detect when we try to build on a platform that doesn't define
      AF_UNSPEC to 0. We don't work there, so refuse to compile.
    - Update to the November 1 2011 Maxmind GeoLite Country database.

  o Packaging changes:
    - Make it easier to automate expert package builds on Windows,
      by removing an absolute path from makensis.exe command.

  o Code simplifications and refactoring:
    - Remove some redundant #include directives throughout the code.
      Patch from Andrea Gelmini.
    - Unconditionally use OpenSSL's AES implementation instead of our
      old built-in one. OpenSSL's AES has been better for a while, and
      relatively few servers should still be on any version of OpenSSL
      that doesn't have good optimized assembly AES.
    - Use the name "CERTS" consistently to refer to the new cell type;
      we were calling it CERT in some places and CERTS in others.

  o Testing:
    - Numerous new unit tests for functions in util.c and address.c by
      Anders Sundman.
    - The long-disabled benchmark tests are now split into their own
      ./src/test/bench binary.
    - The benchmark tests can now use more accurate timers than
      gettimeofday() when such timers are available.


Changes in version 0.2.3.7-alpha - 2011-10-30
  Tor 0.2.3.7-alpha fixes a crash bug in 0.2.3.6-alpha introduced by
  the new v3 handshake. It also resolves yet another bridge address
  enumeration issue.

  o Major bugfixes:
    - If we mark an OR connection for close based on a cell we process,
      don't process any further cells on it. We already avoid further
      reads on marked-for-close connections, but now we also discard the
      cells we'd already read. Fixes bug 4299; bugfix on 0.2.0.10-alpha,
      which was the first version where we might mark a connection for
      close based on processing a cell on it.
    - Fix a double-free bug that would occur when we received an invalid
      certificate in a CERT cell in the new v3 handshake. Fixes bug 4343;
      bugfix on 0.2.3.6-alpha.
    - Bridges no longer include their address in NETINFO cells on outgoing
      OR connections, to allow them to blend in better with clients.
      Removes another avenue for enumerating bridges. Reported by
      "troll_un". Fixes bug 4348; bugfix on 0.2.0.10-alpha, when NETINFO
      cells were introduced.

  o Trivial fixes:
    - Fixed a typo in a hibernation-related log message. Fixes bug 4331;
      bugfix on 0.2.2.23-alpha; found by "tmpname0901".


Changes in version 0.2.3.6-alpha - 2011-10-26
  Tor 0.2.3.6-alpha includes the fix from 0.2.2.34 for a critical
  anonymity vulnerability where an attacker can deanonymize Tor
  users. Everybody should upgrade.

  This release also features support for a new v3 connection handshake
  protocol, and fixes to make hidden service connections more robust.

  o Major features:
    - Implement a new handshake protocol (v3) for authenticating Tors to
      each other over TLS. It should be more resistant to fingerprinting
      than previous protocols, and should require less TLS hacking for
      future Tor implementations. Implements proposal 176.
    - Allow variable-length padding cells to disguise the length of
      Tor's TLS records. Implements part of proposal 184.

  o Privacy/anonymity fixes (clients):
    - Clients and bridges no longer send TLS certificate chains on
      outgoing OR connections. Previously, each client or bridge would
      use the same cert chain for all outgoing OR connections until
      its IP address changes, which allowed any relay that the client
      or bridge contacted to determine which entry guards it is using.
      Fixes CVE-2011-2768. Bugfix on 0.0.9pre5; found by "frosty_un".
    - If a relay receives a CREATE_FAST cell on a TLS connection, it
      no longer considers that connection as suitable for satisfying a
      circuit EXTEND request. Now relays can protect clients from the
      CVE-2011-2768 issue even if the clients haven't upgraded yet.
    - Directory authorities no longer assign the Guard flag to relays
      that haven't upgraded to the above "refuse EXTEND requests
      to client connections" fix. Now directory authorities can
      protect clients from the CVE-2011-2768 issue even if neither
      the clients nor the relays have upgraded yet. There's a new
      "GiveGuardFlagTo_CVE_2011_2768_VulnerableRelays" config option
      to let us transition smoothly, else tomorrow there would be no
      guard relays.

  o Major bugfixes (hidden services):
    - Improve hidden service robustness: when an attempt to connect to
      a hidden service ends, be willing to refetch its hidden service
      descriptors from each of the HSDir relays responsible for them
      immediately. Previously, we would not consider refetching the
      service's descriptors from each HSDir for 15 minutes after the last
      fetch, which was inconvenient if the hidden service was not running
      during the first attempt. Bugfix on 0.2.0.18-alpha; fixes bug 3335.
    - When one of a hidden service's introduction points appears to be
      unreachable, stop trying it. Previously, we would keep trying
      to build circuits to the introduction point until we lost the
      descriptor, usually because the user gave up and restarted Tor.
      Partly fixes bug 3825.
    - Don't launch a useless circuit after failing to use one of a
      hidden service's introduction points. Previously, we would
      launch a new introduction circuit, but not set the hidden service
      which that circuit was intended to connect to, so it would never
      actually be used. A different piece of code would then create a
      new introduction circuit correctly. Bug reported by katmagic and
      found by Sebastian Hahn. Bugfix on 0.2.1.13-alpha; fixes bug 4212.

  o Major bugfixes (other):
    - Bridges now refuse CREATE or CREATE_FAST cells on OR connections
      that they initiated. Relays could distinguish incoming bridge
      connections from client connections, creating another avenue for
      enumerating bridges. Fixes CVE-2011-2769. Bugfix on 0.2.0.3-alpha.
      Found by "frosty_un".
    - Don't update the AccountingSoftLimitHitAt state file entry whenever
      tor gets started. This prevents a wrong average bandwidth
      estimate, which would cause relays to always start a new accounting
      interval at the earliest possible moment. Fixes bug 2003; bugfix
      on 0.2.2.7-alpha. Reported by BryonEldridge, who also helped
      immensely in tracking this bug down.
    - Fix a crash bug when changing node restrictions while a DNS lookup
      is in-progress. Fixes bug 4259; bugfix on 0.2.2.25-alpha. Bugfix
      by "Tey'".

  o Minor bugfixes (on 0.2.2.x and earlier):
    - When a hidden service turns an extra service-side introduction
      circuit into a general-purpose circuit, free the rend_data and
      intro_key fields first, so we won't leak memory if the circuit
      is cannibalized for use as another service-side introduction
      circuit. Bugfix on 0.2.1.7-alpha; fixes bug 4251.
    - Rephrase the log message emitted if the TestSocks check is
      successful. Patch from Fabian Keil; fixes bug 4094.
    - Bridges now skip DNS self-tests, to act a little more stealthily.
      Fixes bug 4201; bugfix on 0.2.0.3-alpha, which first introduced
      bridges. Patch by "warms0x".
    - Remove a confusing dollar sign from the example fingerprint in the
      man page, and also make the example fingerprint a valid one. Fixes
      bug 4309; bugfix on 0.2.1.3-alpha.
    - Fix internal bug-checking logic that was supposed to catch
      failures in digest generation so that it will fail more robustly
      if we ask for a nonexistent algorithm. Found by Coverity Scan.
      Bugfix on 0.2.2.1-alpha; fixes Coverity CID 479.
    - Report any failure in init_keys() calls launched because our
      IP address has changed. Spotted by Coverity Scan. Bugfix on
      0.1.1.4-alpha; fixes CID 484.

  o Minor bugfixes (on 0.2.3.x):
    - Fix a bug in configure.in that kept it from building a configure
      script with autoconf versions earlier than 2.61. Fixes bug 2430;
      bugfix on 0.2.3.1-alpha.
    - Don't warn users that they are exposing a client port to the
      Internet if they have specified an RFC1918 address. Previously,
      we would warn if the user had specified any non-loopback
      address. Bugfix on 0.2.3.3-alpha. Fixes bug 4018; reported by Tas.
    - Fix memory leaks in the failing cases of the new SocksPort and
      ControlPort code. Found by Coverity Scan. Bugfix on 0.2.3.3-alpha;
      fixes coverity CIDs 485, 486, and 487.

  o Minor features:
    - When a hidden service's introduction point times out, consider
      trying it again during the next attempt to connect to the
      HS. Previously, we would not try it again unless a newly fetched
      descriptor contained it. Required by fixes for bugs 1297 and 3825.
    - The next version of Windows will be called Windows 8, and it has
      a major version of 6, minor version of 2. Correctly identify that
      version instead of calling it "Very recent version". Resolves
      ticket 4153; reported by funkstar.
    - The Bridge Authority now writes statistics on how many bridge
      descriptors it gave out in total, and how many unique descriptors
      it gave out. It also lists how often the most and least commonly
      fetched descriptors were given out, as well as the median and
      25th/75th percentile. Implements tickets 4200 and 4294.
    - Update to the October 4 2011 Maxmind GeoLite Country database.

  o Code simplifications and refactoring:
    - Remove some old code to remember statistics about which descriptors
      we've served as a directory mirror. The feature wasn't used and
      is outdated now that microdescriptors are around.
    - Rename Tor functions that turn strings into addresses, so that
      "parse" indicates that no hostname resolution occurs, and
      "lookup" indicates that hostname resolution may occur. This
      should help prevent mistakes in the future. Fixes bug 3512.


Changes in version 0.2.2.34 - 2011-10-26
  Tor 0.2.2.34 fixes a critical anonymity vulnerability where an attacker
  can deanonymize Tor users. Everybody should upgrade.

  The attack relies on four components: 1) Clients reuse their TLS cert
  when talking to different relays, so relays can recognize a user by
  the identity key in her cert. 2) An attacker who knows the client's
  identity key can probe each guard relay to see if that identity key
  is connected to that guard relay right now. 3) A variety of active
  attacks in the literature (starting from "Low-Cost Traffic Analysis
  of Tor" by Murdoch and Danezis in 2005) allow a malicious website to
  discover the guard relays that a Tor user visiting the website is using.
  4) Clients typically pick three guards at random, so the set of guards
  for a given user could well be a unique fingerprint for her. This
  release fixes components #1 and #2, which is enough to block the attack;
  the other two remain as open research problems. Special thanks to
  "frosty_un" for reporting the issue to us!

  Clients should upgrade so they are no longer recognizable by the TLS
  certs they present. Relays should upgrade so they no longer allow a
  remote attacker to probe them to test whether unpatched clients are
  currently connected to them.

  This release also fixes several vulnerabilities that allow an attacker
  to enumerate bridge relays. Some bridge enumeration attacks still
  remain; see for example proposal 188.

  o Privacy/anonymity fixes (clients):
    - Clients and bridges no longer send TLS certificate chains on
      outgoing OR connections. Previously, each client or bridge would
      use the same cert chain for all outgoing OR connections until
      its IP address changes, which allowed any relay that the client
      or bridge contacted to determine which entry guards it is using.
      Fixes CVE-2011-2768. Bugfix on 0.0.9pre5; found by "frosty_un".
    - If a relay receives a CREATE_FAST cell on a TLS connection, it
      no longer considers that connection as suitable for satisfying a
      circuit EXTEND request. Now relays can protect clients from the
      CVE-2011-2768 issue even if the clients haven't upgraded yet.
    - Directory authorities no longer assign the Guard flag to relays
      that haven't upgraded to the above "refuse EXTEND requests
      to client connections" fix. Now directory authorities can
      protect clients from the CVE-2011-2768 issue even if neither
      the clients nor the relays have upgraded yet. There's a new
      "GiveGuardFlagTo_CVE_2011_2768_VulnerableRelays" config option
      to let us transition smoothly, else tomorrow there would be no
      guard relays.

  o Privacy/anonymity fixes (bridge enumeration):
    - Bridge relays now do their directory fetches inside Tor TLS
      connections, like all the other clients do, rather than connecting
      directly to the DirPort like public relays do. Removes another
      avenue for enumerating bridges. Fixes bug 4115; bugfix on 0.2.0.35.
    - Bridges relays now build circuits for themselves in a more similar
      way to how clients build them. Removes another avenue for
      enumerating bridges. Fixes bug 4124; bugfix on 0.2.0.3-alpha,
      when bridges were introduced.
    - Bridges now refuse CREATE or CREATE_FAST cells on OR connections
      that they initiated. Relays could distinguish incoming bridge
      connections from client connections, creating another avenue for
      enumerating bridges. Fixes CVE-2011-2769. Bugfix on 0.2.0.3-alpha.
      Found by "frosty_un".

  o Major bugfixes:
    - Fix a crash bug when changing node restrictions while a DNS lookup
      is in-progress. Fixes bug 4259; bugfix on 0.2.2.25-alpha. Bugfix
      by "Tey'".
    - Don't launch a useless circuit after failing to use one of a
      hidden service's introduction points. Previously, we would
      launch a new introduction circuit, but not set the hidden service
      which that circuit was intended to connect to, so it would never
      actually be used. A different piece of code would then create a
      new introduction circuit correctly. Bug reported by katmagic and
      found by Sebastian Hahn. Bugfix on 0.2.1.13-alpha; fixes bug 4212.

  o Minor bugfixes:
    - Change an integer overflow check in the OpenBSD_Malloc code so
      that GCC is less likely to eliminate it as impossible. Patch
      from Mansour Moufid. Fixes bug 4059.
    - When a hidden service turns an extra service-side introduction
      circuit into a general-purpose circuit, free the rend_data and
      intro_key fields first, so we won't leak memory if the circuit
      is cannibalized for use as another service-side introduction
      circuit. Bugfix on 0.2.1.7-alpha; fixes bug 4251.
    - Bridges now skip DNS self-tests, to act a little more stealthily.
      Fixes bug 4201; bugfix on 0.2.0.3-alpha, which first introduced
      bridges. Patch by "warms0x".
    - Fix internal bug-checking logic that was supposed to catch
      failures in digest generation so that it will fail more robustly
      if we ask for a nonexistent algorithm. Found by Coverity Scan.
      Bugfix on 0.2.2.1-alpha; fixes Coverity CID 479.
    - Report any failure in init_keys() calls launched because our
      IP address has changed. Spotted by Coverity Scan. Bugfix on
      0.1.1.4-alpha; fixes CID 484.

  o Minor bugfixes (log messages and documentation):
    - Remove a confusing dollar sign from the example fingerprint in the
      man page, and also make the example fingerprint a valid one. Fixes
      bug 4309; bugfix on 0.2.1.3-alpha.
    - The next version of Windows will be called Windows 8, and it has
      a major version of 6, minor version of 2. Correctly identify that
      version instead of calling it "Very recent version". Resolves
      ticket 4153; reported by funkstar.
    - Downgrade log messages about circuit timeout calibration from
      "notice" to "info": they don't require or suggest any human
      intervention. Patch from Tom Lowenthal. Fixes bug 4063;
      bugfix on 0.2.2.14-alpha.

  o Minor features:
    - Turn on directory request statistics by default and include them in
      extra-info descriptors. Don't break if we have no GeoIP database.
      Backported from 0.2.3.1-alpha; implements ticket 3951.
    - Update to the October 4 2011 Maxmind GeoLite Country database.


Changes in version 0.2.1.31 - 2011-10-26
  Tor 0.2.1.31 backports important security and privacy fixes for
  oldstable. This release is intended only for package maintainers and
  others who cannot use the 0.2.2 stable series. All others should be
  using Tor 0.2.2.x or newer.

  o Security fixes (also included in 0.2.2.x):
    - Replace all potentially sensitive memory comparison operations
      with versions whose runtime does not depend on the data being
      compared. This will help resist a class of attacks where an
      adversary can use variations in timing information to learn
      sensitive data. Fix for one case of bug 3122. (Safe memcmp
      implementation by Robert Ransom based partially on code by DJB.)
    - Fix an assert in parsing router descriptors containing IPv6
      addresses. This one took down the directory authorities when
      somebody tried some experimental code. Bugfix on 0.2.1.3-alpha.

  o Privacy/anonymity fixes (also included in 0.2.2.x):
    - Clients and bridges no longer send TLS certificate chains on
      outgoing OR connections. Previously, each client or bridge would
      use the same cert chain for all outgoing OR connections until
      its IP address changes, which allowed any relay that the client
      or bridge contacted to determine which entry guards it is using.
      Fixes CVE-2011-2768. Bugfix on 0.0.9pre5; found by "frosty_un".
    - If a relay receives a CREATE_FAST cell on a TLS connection, it
      no longer considers that connection as suitable for satisfying a
      circuit EXTEND request. Now relays can protect clients from the
      CVE-2011-2768 issue even if the clients haven't upgraded yet.
    - Bridges now refuse CREATE or CREATE_FAST cells on OR connections
      that they initiated. Relays could distinguish incoming bridge
      connections from client connections, creating another avenue for
      enumerating bridges. Fixes CVE-2011-2769. Bugfix on 0.2.0.3-alpha.
      Found by "frosty_un".
    - When receiving a hidden service descriptor, check that it is for
      the hidden service we wanted. Previously, Tor would store any
      hidden service descriptors that a directory gave it, whether it
      wanted them or not. This wouldn't have let an attacker impersonate
      a hidden service, but it did let directories pre-seed a client
      with descriptors that it didn't want. Bugfix on 0.0.6.
    - Avoid linkability based on cached hidden service descriptors: forget
      all hidden service descriptors cached as a client when processing a
      SIGNAL NEWNYM command. Fixes bug 3000; bugfix on 0.0.6.
    - Make the bridge directory authority refuse to answer directory
      requests for "all" descriptors. It used to include bridge
      descriptors in its answer, which was a major information leak.
      Found by "piebeer". Bugfix on 0.2.0.3-alpha.
    - Don't attach new streams to old rendezvous circuits after SIGNAL
      NEWNYM. Previously, we would keep using an existing rendezvous
      circuit if it remained open (i.e. if it were kept open by a
      long-lived stream, or if a new stream were attached to it before
      Tor could notice that it was old and no longer in use). Bugfix on
      0.1.1.15-rc; fixes bug 3375.

  o Minor bugfixes (also included in 0.2.2.x):
    - When we restart our relay, we might get a successful connection
      from the outside before we've started our reachability tests,
      triggering a warning: "ORPort found reachable, but I have no
      routerinfo yet. Failing to inform controller of success." This
      bug was harmless unless Tor is running under a controller
      like Vidalia, in which case the controller would never get a
      REACHABILITY_SUCCEEDED status event. Bugfix on 0.1.2.6-alpha;
      fixes bug 1172.
    - Build correctly on OSX with zlib 1.2.4 and higher with all warnings
      enabled. Fixes bug 1526.
    - Remove undocumented option "-F" from tor-resolve: it hasn't done
      anything since 0.2.1.16-rc.
    - Avoid signed/unsigned comparisons by making SIZE_T_CEILING unsigned.
      None of the cases where we did this before were wrong, but by making
      this change we avoid warnings. Fixes bug 2475; bugfix on 0.2.1.28.
    - Fix a rare crash bug that could occur when a client was configured
      with a large number of bridges. Fixes bug 2629; bugfix on
      0.2.1.2-alpha. Bugfix by trac user "shitlei".
    - Correct the warning displayed when a rendezvous descriptor exceeds
      the maximum size. Fixes bug 2750; bugfix on 0.2.1.5-alpha. Found by
      John Brooks.
    - Fix an uncommon assertion failure when running with DNSPort under
      heavy load. Fixes bug 2933; bugfix on 0.2.0.1-alpha.
    - When warning about missing zlib development packages during compile,
      give the correct package names. Bugfix on 0.2.0.1-alpha.
    - Require that introduction point keys and onion keys have public
      exponent 65537. Bugfix on 0.2.0.10-alpha.
    - Do not crash when our configuration file becomes unreadable, for
      example due to a permissions change, between when we start up
      and when a controller calls SAVECONF. Fixes bug 3135; bugfix
      on 0.0.9pre6.
    - Fix warnings from GCC 4.6's "-Wunused-but-set-variable" option.
      Fixes bug 3208.
    - Always NUL-terminate the sun_path field of a sockaddr_un before
      passing it to the kernel. (Not a security issue: kernels are
      smart enough to reject bad sockaddr_uns.) Found by Coverity;
      CID #428. Bugfix on Tor 0.2.0.3-alpha.
    - Don't stack-allocate the list of supplementary GIDs when we're
      about to log them. Stack-allocating NGROUPS_MAX gid_t elements
      could take up to 256K, which is way too much stack. Found by
      Coverity; CID #450. Bugfix on 0.2.1.7-alpha.

  o Minor bugfixes (only in 0.2.1.x):
    - Resume using micro-version numbers in 0.2.1.x: our Debian packages
      rely on them. Bugfix on 0.2.1.30.
    - Use git revisions instead of svn revisions when generating our
      micro-version numbers. Bugfix on 0.2.1.15-rc; fixes bug 2402.

  o Minor features (also included in 0.2.2.x):
    - Adjust the expiration time on our SSL session certificates to
      better match SSL certs seen in the wild. Resolves ticket 4014.
    - Allow nameservers with IPv6 address. Resolves bug 2574.
    - Update to the October 4 2011 Maxmind GeoLite Country database.


Changes in version 0.2.3.5-alpha - 2011-09-28
  Tor 0.2.3.5-alpha fixes two bugs that make it possible to enumerate
  bridge relays; fixes an assertion error that many users started hitting
  today; and adds the ability to refill token buckets more often than
  once per second, allowing significant performance improvements.

  o Security fixes:
    - Bridge relays now do their directory fetches inside Tor TLS
      connections, like all the other clients do, rather than connecting
      directly to the DirPort like public relays do. Removes another
      avenue for enumerating bridges. Fixes bug 4115; bugfix on 0.2.0.35.
    - Bridges relays now build circuits for themselves in a more similar
      way to how clients build them. Removes another avenue for
      enumerating bridges. Fixes bug 4124; bugfix on 0.2.0.3-alpha,
      when bridges were introduced.

  o Major bugfixes:
    - Fix an "Assertion md->held_by_node == 1 failed" error that could
      occur when the same microdescriptor was referenced by two node_t
      objects at once. Fix for bug 4118; bugfix on Tor 0.2.3.1-alpha.

  o Major features (networking):
    - Add a new TokenBucketRefillInterval option to refill token buckets
      more frequently than once per second. This should improve network
      performance, alleviate queueing problems, and make traffic less
      bursty. Implements proposal 183; closes ticket 3630. Design by
      Florian Tschorsch and Björn Scheuermann; implementation by
      Florian Tschorsch.

  o Minor bugfixes:
    - Change an integer overflow check in the OpenBSD_Malloc code so
      that GCC is less likely to eliminate it as impossible. Patch
      from Mansour Moufid. Fixes bug 4059.

  o Minor bugfixes (usability):
    - Downgrade log messages about circuit timeout calibration from
      "notice" to "info": they don't require or suggest any human
      intervention. Patch from Tom Lowenthal. Fixes bug 4063;
      bugfix on 0.2.2.14-alpha.

  o Minor features (diagnostics):
    - When the system call to create a listener socket fails, log the
      error message explaining why. This may help diagnose bug 4027.


Changes in version 0.2.3.4-alpha - 2011-09-13
  Tor 0.2.3.4-alpha includes the fixes from 0.2.2.33, including a slight
  tweak to Tor's TLS handshake that makes relays and bridges that run
  this new version reachable from Iran again. It also fixes a few new
  bugs in 0.2.3.x, and teaches relays to recognize when they're not
  listed in the network consensus and republish.

  o Major bugfixes (also part of 0.2.2.33):
    - Avoid an assertion failure when reloading a configuration with
      TrackExitHosts changes. Found and fixed by 'laruldan'. Fixes bug
      3923; bugfix on 0.2.2.25-alpha.

  o Minor features (security, also part of 0.2.2.33):
    - Check for replays of the public-key encrypted portion of an
      INTRODUCE1 cell, in addition to the current check for replays of
      the g^x value. This prevents a possible class of active attacks
      by an attacker who controls both an introduction point and a
      rendezvous point, and who uses the malleability of AES-CTR to
      alter the encrypted g^x portion of the INTRODUCE1 cell. We think
      that these attacks are infeasible (requiring the attacker to send
      on the order of zettabytes of altered cells in a short interval),
      but we'd rather block them off in case there are any classes of
      this attack that we missed. Reported by Willem Pinckaers.

  o Minor features (also part of 0.2.2.33):
    - Adjust the expiration time on our SSL session certificates to
      better match SSL certs seen in the wild. Resolves ticket 4014.
    - Change the default required uptime for a relay to be accepted as
      a HSDir (hidden service directory) from 24 hours to 25 hours.
      Improves on 0.2.0.10-alpha; resolves ticket 2649.
    - Add a VoteOnHidServDirectoriesV2 config option to allow directory
      authorities to abstain from voting on assignment of the HSDir
      consensus flag. Related to bug 2649.
    - Update to the September 6 2011 Maxmind GeoLite Country database.

  o Minor bugfixes (also part of 0.2.2.33):
    - Demote the 'replay detected' log message emitted when a hidden
      service receives the same Diffie-Hellman public key in two different
      INTRODUCE2 cells to info level. A normal Tor client can cause that
      log message during its normal operation. Bugfix on 0.2.1.6-alpha;
      fixes part of bug 2442.
    - Demote the 'INTRODUCE2 cell is too {old,new}' log message to info
      level. There is nothing that a hidden service's operator can do
      to fix its clients' clocks. Bugfix on 0.2.1.6-alpha; fixes part
      of bug 2442.
    - Clarify a log message specifying the characters permitted in
      HiddenServiceAuthorizeClient client names. Previously, the log
      message said that "[A-Za-z0-9+-_]" were permitted; that could have
      given the impression that every ASCII character between "+" and "_"
      was permitted. Now we say "[A-Za-z0-9+_-]". Bugfix on 0.2.1.5-alpha.

  o Build fixes (also part of 0.2.2.33):
    - Clean up some code issues that prevented Tor from building on older
      BSDs. Fixes bug 3894; reported by "grarpamp".
    - Search for a platform-specific version of "ar" when cross-compiling.
      Should fix builds on iOS. Resolves bug 3909, found by Marco Bonetti.

  o Major bugfixes:
    - Fix a bug where the SocksPort option (for example) would get
      ignored and replaced by the default if a SocksListenAddress
      option was set. Bugfix on 0.2.3.3-alpha; fixes bug 3936. Fix by
      Fabian Keil.

  o Major features:
    - Relays now try regenerating and uploading their descriptor more
      frequently if they are not listed in the consensus, or if the
      version of their descriptor listed in the consensus is too
      old. This fix should prevent situations where a server declines
      to re-publish itself because it has done so too recently, even
      though the authorities decided not to list its recent-enough
      descriptor. Fix for bug 3327.

  o Minor features:
    - Relays now include a reason for regenerating their descriptors
      in an HTTP header when uploading to the authorities. This will
      make it easier to debug descriptor-upload issues in the future.
    - When starting as root and then changing our UID via the User
      control option, and we have a ControlSocket configured, make sure
      that the ControlSocket is owned by the same account that Tor will
      run under. Implements ticket 3421; fix by Jérémy Bobbio.

  o Minor bugfixes:
    - Abort if tor_vasprintf fails in connection_printf_to_buf (a
      utility function used in the control-port code). This shouldn't
      ever happen unless Tor is completely out of memory, but if it did
      happen and Tor somehow recovered from it, Tor could have sent a log
      message to a control port in the middle of a reply to a controller
      command. Fixes part of bug 3428; bugfix on 0.1.2.3-alpha.
    - Make 'FetchUselessDescriptors' cause all descriptor types and
      all consensus types (including microdescriptors) to get fetched.
      Fixes bug 3851; bugfix on 0.2.3.1-alpha.

  o Code refactoring:
    - Make a new "entry connection" struct as an internal subtype of "edge
      connection", to simplify the code and make exit connections smaller.


Changes in version 0.2.2.33 - 2011-09-13
  Tor 0.2.2.33 fixes several bugs, and includes a slight tweak to Tor's
  TLS handshake that makes relays and bridges that run this new version
  reachable from Iran again.

  o Major bugfixes:
    - Avoid an assertion failure when reloading a configuration with
      TrackExitHosts changes. Found and fixed by 'laruldan'. Fixes bug
      3923; bugfix on 0.2.2.25-alpha.

  o Minor features (security):
    - Check for replays of the public-key encrypted portion of an
      INTRODUCE1 cell, in addition to the current check for replays of
      the g^x value. This prevents a possible class of active attacks
      by an attacker who controls both an introduction point and a
      rendezvous point, and who uses the malleability of AES-CTR to
      alter the encrypted g^x portion of the INTRODUCE1 cell. We think
      that these attacks are infeasible (requiring the attacker to send
      on the order of zettabytes of altered cells in a short interval),
      but we'd rather block them off in case there are any classes of
      this attack that we missed. Reported by Willem Pinckaers.

  o Minor features:
    - Adjust the expiration time on our SSL session certificates to
      better match SSL certs seen in the wild. Resolves ticket 4014.
    - Change the default required uptime for a relay to be accepted as
      a HSDir (hidden service directory) from 24 hours to 25 hours.
      Improves on 0.2.0.10-alpha; resolves ticket 2649.
    - Add a VoteOnHidServDirectoriesV2 config option to allow directory
      authorities to abstain from voting on assignment of the HSDir
      consensus flag. Related to bug 2649.
    - Update to the September 6 2011 Maxmind GeoLite Country database.

  o Minor bugfixes (documentation and log messages):
    - Correct the man page to explain that HashedControlPassword and
      CookieAuthentication can both be set, in which case either method
      is sufficient to authenticate to Tor. Bugfix on 0.2.0.7-alpha,
      when we decided to allow these config options to both be set. Issue
      raised by bug 3898.
    - Demote the 'replay detected' log message emitted when a hidden
      service receives the same Diffie-Hellman public key in two different
      INTRODUCE2 cells to info level. A normal Tor client can cause that
      log message during its normal operation. Bugfix on 0.2.1.6-alpha;
      fixes part of bug 2442.
    - Demote the 'INTRODUCE2 cell is too {old,new}' log message to info
      level. There is nothing that a hidden service's operator can do
      to fix its clients' clocks. Bugfix on 0.2.1.6-alpha; fixes part
      of bug 2442.
    - Clarify a log message specifying the characters permitted in
      HiddenServiceAuthorizeClient client names. Previously, the log
      message said that "[A-Za-z0-9+-_]" were permitted; that could have
      given the impression that every ASCII character between "+" and "_"
      was permitted. Now we say "[A-Za-z0-9+_-]". Bugfix on 0.2.1.5-alpha.

  o Build fixes:
    - Provide a substitute implementation of lround() for MSVC, which
      apparently lacks it. Patch from Gisle Vanem.
    - Clean up some code issues that prevented Tor from building on older
      BSDs. Fixes bug 3894; reported by "grarpamp".
    - Search for a platform-specific version of "ar" when cross-compiling.
      Should fix builds on iOS. Resolves bug 3909, found by Marco Bonetti.


Changes in version 0.2.3.3-alpha - 2011-09-01
  Tor 0.2.3.3-alpha adds a new "stream isolation" feature to improve Tor's
  security, and provides client-side support for the microdescriptor
  and optimistic data features introduced earlier in the 0.2.3.x
  series. It also includes numerous critical bugfixes in the (optional)
  bufferevent-based networking backend.

  o Major features (stream isolation):
    - You can now configure Tor so that streams from different
      applications are isolated on different circuits, to prevent an
      attacker who sees your streams as they leave an exit node from
      linking your sessions to one another. To do this, choose some way
      to distinguish the applications: have them connect to different
      SocksPorts, or have one of them use SOCKS4 while the other uses
      SOCKS5, or have them pass different authentication strings to the
      SOCKS proxy. Then, use the new SocksPort syntax to configure the
      degree of isolation you need. This implements Proposal 171.
    - There's a new syntax for specifying multiple client ports (such as
      SOCKSPort, TransPort, DNSPort, NATDPort): you can now just declare
      multiple *Port entries with full addr:port syntax on each.
      The old *ListenAddress format is still supported, but you can't
      mix it with the new *Port syntax.

  o Major features (other):
    - Enable microdescriptor fetching by default for clients. This allows
      clients to download a much smaller amount of directory information.
      To disable it (and go back to the old-style consensus and
      descriptors), set "UseMicrodescriptors 0" in your torrc file.
    - Tor's firewall-helper feature, introduced in 0.2.3.1-alpha (see the
      "PortForwarding" config option), now supports Windows.
    - When using an exit relay running 0.2.3.x, clients can now
      "optimistically" send data before the exit relay reports that
      the stream has opened. This saves a round trip when starting
      connections where the client speaks first (such as web browsing).
      This behavior is controlled by a consensus parameter (currently
      disabled). To turn it on or off manually, use the "OptimisticData"
      torrc option. Implements proposal 181; code by Ian Goldberg.

  o Major bugfixes (bufferevents, fixes on 0.2.3.1-alpha):
    - When using IOCP on Windows, we need to enable Libevent windows
      threading support.
    - The IOCP backend now works even when the user has not specified
      the (internal, debugging-only) _UseFilteringSSLBufferevents option.
      Fixes part of bug 3752.
    - Correctly record the bytes we've read and written when using
      bufferevents, so that we can include them in our bandwidth history
      and advertised bandwidth. Fixes bug 3803.
    - Apply rate-limiting only at the bottom of a chain of filtering
      bufferevents. This prevents us from filling up internal read
      buffers and violating rate-limits when filtering bufferevents
      are enabled. Fixes part of bug 3804.
    - Add high-watermarks to the output buffers for filtered
      bufferevents. This prevents us from filling up internal write
      buffers and wasting CPU cycles when filtering bufferevents are
      enabled. Fixes part of bug 3804.
    - Correctly notice when data has been written from a bufferevent
      without flushing it completely. Fixes bug 3805.
    - Fix a bug where server-side tunneled bufferevent-based directory
      streams would get closed prematurely. Fixes bug 3814.
    - Fix a use-after-free error with per-connection rate-limiting
      buckets. Fixes bug 3888.

  o Major bugfixes (also part of 0.2.2.31-rc):
    - If we're configured to write our ControlPorts to disk, only write
      them after switching UID and creating the data directory. This way,
      we don't fail when starting up with a nonexistent DataDirectory
      and a ControlPortWriteToFile setting based on that directory. Fixes
      bug 3747; bugfix on Tor 0.2.2.26-beta.

  o Minor features:
    - Added a new CONF_CHANGED event so that controllers can be notified
      of any configuration changes made by other controllers, or by the
      user. Implements ticket 1692.
    - Use evbuffer_copyout() in inspect_evbuffer(). This fixes a memory
      leak when using bufferevents, and lets Libevent worry about how to
      best copy data out of a buffer.
    - Replace files in stats/ rather than appending to them. Now that we
      include statistics in extra-info descriptors, it makes no sense to
      keep old statistics forever. Implements ticket 2930.

  o Minor features (build compatibility):
    - Limited, experimental support for building with nmake and MSVC.
    - Provide a substitute implementation of lround() for MSVC, which
      apparently lacks it. Patch from Gisle Vanem.

  o Minor features (also part of 0.2.2.31-rc):
    - Update to the August 2 2011 Maxmind GeoLite Country database.

  o Minor bugfixes (on 0.2.3.x-alpha):
    - Fix a spurious warning when parsing SOCKS requests with
      bufferevents enabled. Fixes bug 3615; bugfix on 0.2.3.2-alpha.
    - Get rid of a harmless warning that could happen on relays running
      with bufferevents. The warning was caused by someone doing an http
      request to a relay's orport. Also don't warn for a few related
      non-errors. Fixes bug 3700; bugfix on 0.2.3.1-alpha.

  o Minor bugfixes (on 2.2.x and earlier):
    - Correct the man page to explain that HashedControlPassword and
      CookieAuthentication can both be set, in which case either method
      is sufficient to authenticate to Tor. Bugfix on 0.2.0.7-alpha,
      when we decided to allow these config options to both be set. Issue
      raised by bug 3898.
    - The "--quiet" and "--hush" options now apply not only to Tor's
      behavior before logs are configured, but also to Tor's behavior in
      the absence of configured logs. Fixes bug 3550; bugfix on
      0.2.0.10-alpha.

  o Minor bugfixes (also part of 0.2.2.31-rc):
    - Write several files in text mode, on OSes that distinguish text
      mode from binary mode (namely, Windows). These files are:
      'buffer-stats', 'dirreq-stats', and 'entry-stats' on relays
      that collect those statistics; 'client_keys' and 'hostname' for
      hidden services that use authentication; and (in the tor-gencert
      utility) newly generated identity and signing keys. Previously,
      we wouldn't specify text mode or binary mode, leading to an
      assertion failure. Fixes bug 3607. Bugfix on 0.2.1.1-alpha (when
      the DirRecordUsageByCountry option which would have triggered
      the assertion failure was added), although this assertion failure
      would have occurred in tor-gencert on Windows in 0.2.0.1-alpha.
    - Selectively disable deprecation warnings on OS X because Lion
      started deprecating the shipped copy of openssl. Fixes bug 3643.
    - Remove an extra pair of quotation marks around the error
      message in control-port STATUS_GENERAL BUG events. Bugfix on
      0.1.2.6-alpha; fixes bug 3732.
    - When unable to format an address as a string, report its value
      as "???" rather than reusing the last formatted address. Bugfix
      on 0.2.1.5-alpha.

  o Code simplifications and refactoring:
    - Rewrite the listener-selection logic so that parsing which ports
      we want to listen on is now separate from binding to the ports
      we want.

  o Build changes:
    - Building Tor with bufferevent support now requires Libevent
      2.0.13-stable or later. Previous versions of Libevent had bugs in
      SSL-related bufferevents and related issues that would make Tor
      work badly with bufferevents. Requiring 2.0.13-stable also allows
      Tor with bufferevents to take advantage of Libevent APIs
      introduced after 2.0.8-rc.


Changes in version 0.2.2.32 - 2011-08-27
  The Tor 0.2.2 release series is dedicated to the memory of Andreas
  Pfitzmann (1958-2010), a pioneer in anonymity and privacy research,
  a founder of the PETS community, a leader in our field, a mentor,
  and a friend. He left us with these words: "I had the possibility
  to contribute to this world that is not as it should be. I hope I
  could help in some areas to make the world a better place, and that
  I could also encourage other people to be engaged in improving the
  world. Please, stay engaged. This world needs you, your love, your
  initiative -- now I cannot be part of that anymore."

  Tor 0.2.2.32, the first stable release in the 0.2.2 branch, is finally
  ready. More than two years in the making, this release features improved
  client performance and hidden service reliability, better compatibility
  for Android, correct behavior for bridges that listen on more than
  one address, more extensible and flexible directory object handling,
  better reporting of network statistics, improved code security, and
  many many other features and bugfixes.


Changes in version 0.2.2.31-rc - 2011-08-17
  Tor 0.2.2.31-rc is the second and hopefully final release candidate
  for the Tor 0.2.2.x series.

  o Major bugfixes:
    - Remove an extra pair of quotation marks around the error
      message in control-port STATUS_GENERAL BUG events. Bugfix on
      0.1.2.6-alpha; fixes bug 3732.
    - If we're configured to write our ControlPorts to disk, only write
      them after switching UID and creating the data directory. This way,
      we don't fail when starting up with a nonexistent DataDirectory
      and a ControlPortWriteToFile setting based on that directory. Fixes
      bug 3747; bugfix on Tor 0.2.2.26-beta.

  o Minor features:
    - Update to the August 2 2011 Maxmind GeoLite Country database.

  o Minor bugfixes:
    - Allow GETINFO fingerprint to return a fingerprint even when
      we have not yet built a router descriptor. Fixes bug 3577;
      bugfix on 0.2.0.1-alpha.
    - Write several files in text mode, on OSes that distinguish text
      mode from binary mode (namely, Windows). These files are:
      'buffer-stats', 'dirreq-stats', and 'entry-stats' on relays
      that collect those statistics; 'client_keys' and 'hostname' for
      hidden services that use authentication; and (in the tor-gencert
      utility) newly generated identity and signing keys. Previously,
      we wouldn't specify text mode or binary mode, leading to an
      assertion failure. Fixes bug 3607. Bugfix on 0.2.1.1-alpha (when
      the DirRecordUsageByCountry option which would have triggered
      the assertion failure was added), although this assertion failure
      would have occurred in tor-gencert on Windows in 0.2.0.1-alpha.
    - Selectively disable deprecation warnings on OS X because Lion
      started deprecating the shipped copy of openssl. Fixes bug 3643.
    - When unable to format an address as a string, report its value
      as "???" rather than reusing the last formatted address. Bugfix
      on 0.2.1.5-alpha.


Changes in version 0.2.3.2-alpha - 2011-07-18
  Tor 0.2.3.2-alpha introduces two new experimental features:
  microdescriptors and pluggable transports. It also continues cleaning
  up a variety of recently introduced features.

  o Major features:
    - Clients can now use microdescriptors instead of regular descriptors
      to build circuits. Microdescriptors are authority-generated
      summaries of regular descriptors' contents, designed to change
      very rarely (see proposal 158 for details). This feature is
      designed to save bandwidth, especially for clients on slow internet
      connections. It's off by default for now, since nearly no caches
      support it, but it will be on-by-default for clients in a future
      version. You can use the UseMicrodescriptors option to turn it on.
    - Tor clients using bridges can now be configured to use a separate
      'transport' proxy for each bridge. This approach helps to resist
      censorship by allowing bridges to use protocol obfuscation
      plugins. It implements part of proposal 180. Implements ticket 2841.
    - While we're trying to bootstrap, record how many TLS connections
      fail in each state, and report which states saw the most failures
      in response to any bootstrap failures. This feature may speed up
      diagnosis of censorship events. Implements ticket 3116.

  o Major bugfixes (on 0.2.3.1-alpha):
    - When configuring a large set of nodes in EntryNodes (as with
      'EntryNodes {cc}' or 'EntryNodes 1.1.1.1/16'), choose only a
      random subset to be guards, and choose them in random
      order. Fixes bug 2798.
    - Tor could crash when remembering a consensus in a non-used consensus
      flavor without having a current consensus set. Fixes bug 3361.
    - Comparing an unknown address to a microdescriptor's shortened exit
      policy would always give a "rejected" result. Fixes bug 3599.
    - Using microdescriptors as a client no longer prevents Tor from
      uploading and downloading hidden service descriptors. Fixes
      bug 3601.

  o Minor features:
    - Allow nameservers with IPv6 address. Resolves bug 2574.
    - Accept attempts to include a password authenticator in the
      handshake, as supported by SOCKS5. This handles SOCKS clients that
      don't know how to omit a password when authenticating. Resolves
      bug 1666.
    - When configuring a large set of nodes in EntryNodes, and there are
      enough of them listed as Guard so that we don't need to consider
      the non-guard entries, prefer the ones listed with the Guard flag.
    - Check for and recover from inconsistency in the microdescriptor
      cache. This will make it harder for us to accidentally free a
      microdescriptor without removing it from the appropriate data
      structures. Fixes issue 3135; issue noted by "wanoskarnet".
    - Log SSL state transitions at log level DEBUG, log domain
      HANDSHAKE. This can be useful for debugging censorship events.
      Implements ticket 3264.
    - Add port 6523 (Gobby) to LongLivedPorts. Patch by intrigeri;
      implements ticket 3439.

  o Minor bugfixes (on 0.2.3.1-alpha):
    - Do not free all general-purpose regular descriptors just
      because microdescriptor use is enabled. Fixes bug 3113.
    - Correctly link libevent_openssl when --enable-static-libevent
      is passed to configure. Fixes bug 3118.
    - Bridges should not complain during their heartbeat log messages that
      they are unlisted in the consensus: that's more or less the point
      of being a bridge. Fixes bug 3183.
    - Report a SIGNAL event to controllers when acting on a delayed
      SIGNAL NEWNYM command. Previously, we would report a SIGNAL
      event to the controller if we acted on a SIGNAL NEWNYM command
      immediately, and otherwise not report a SIGNAL event for the
      command at all. Fixes bug 3349.
    - Fix a crash when handling the SIGNAL controller command or
      reporting ERR-level status events with bufferevents enabled. Found
      by Robert Ransom. Fixes bug 3367.
    - Always ship the tor-fw-helper manpage in our release tarballs.
      Fixes bug 3389. Reported by Stephen Walker.
    - Fix a class of double-mark-for-close bugs when bufferevents
      are enabled. Fixes bug 3403.
    - Update tor-fw-helper to support libnatpmp-20110618. Fixes bug 3434.
    - Add SIGNAL to the list returned by the 'GETINFO events/names'
      control-port command. Fixes part of bug 3465.
    - Prevent using negative indices during unit test runs when read_all()
      fails. Spotted by coverity.
    - Fix a rare memory leak when checking the nodelist without it being
      present. Found by coverity.
    - Only try to download a microdescriptor-flavored consensus from
      a directory cache that provides them.

  o Minor bugfixes (on 0.2.2.x and earlier):
    - Assert that hidden-service-related operations are not performed
      using single-hop circuits. Previously, Tor would assert that
      client-side streams are not attached to single-hop circuits,
      but not that other sensitive operations on the client and service
      side are not performed using single-hop circuits. Fixes bug 3332;
      bugfix on 0.0.6.
    - Don't publish a new relay descriptor when we reload our onion key,
      unless the onion key has actually changed. Fixes bug 3263 and
      resolves another cause of bug 1810. Bugfix on 0.1.1.11-alpha.
    - Allow GETINFO fingerprint to return a fingerprint even when
      we have not yet built a router descriptor. Fixes bug 3577;
      bugfix on 0.2.0.1-alpha.
    - Make 'tor --digests' list hashes of all Tor source files. Bugfix
      on 0.2.2.4-alpha; fixes bug 3427.

  o Code simplification and refactoring:
    - Use tor_sscanf() in place of scanf() in more places through the
      code. This makes us a little more locale-independent, and
      should help shut up code-analysis tools that can't tell
      a safe sscanf string from a dangerous one.
    - Use tt_assert(), not tor_assert(), for checking for test failures.
      This makes the unit tests more able to go on in the event that
      one of them fails.
    - Split connection_about_to_close() into separate functions for each
      connection type.

  o Build changes:
    - On Windows, we now define the _WIN32_WINNT macros only if they
      are not already defined. This lets the person building Tor decide,
      if they want, to require a later version of Windows.


Changes in version 0.2.2.30-rc - 2011-07-07
  Tor 0.2.2.30-rc is the first release candidate for the Tor 0.2.2.x
  series. It fixes a few smaller bugs, but generally appears stable.
  Please test it and let us know whether it is!

  o Minor bugfixes:
    - Send a SUCCEEDED stream event to the controller when a reverse
      resolve succeeded. Fixes bug 3536; bugfix on 0.0.8pre1. Issue
      discovered by katmagic.
    - Always NUL-terminate the sun_path field of a sockaddr_un before
      passing it to the kernel. (Not a security issue: kernels are
      smart enough to reject bad sockaddr_uns.) Found by Coverity;
      CID #428. Bugfix on Tor 0.2.0.3-alpha.
    - Don't stack-allocate the list of supplementary GIDs when we're
      about to log them. Stack-allocating NGROUPS_MAX gid_t elements
      could take up to 256K, which is way too much stack. Found by
      Coverity; CID #450. Bugfix on 0.2.1.7-alpha.
    - Add BUILDTIMEOUT_SET to the list returned by the 'GETINFO
      events/names' control-port command. Bugfix on 0.2.2.9-alpha;
      fixes part of bug 3465.
    - Fix a memory leak when receiving a descriptor for a hidden
      service we didn't ask for. Found by Coverity; CID #30. Bugfix
      on 0.2.2.26-beta.

  o Minor features:
    - Update to the July 1 2011 Maxmind GeoLite Country database.


Changes in version 0.2.2.29-beta - 2011-06-20
  Tor 0.2.2.29-beta reverts an accidental behavior change for users who
  have bridge lines in their torrc but don't want to use them; gets
  us closer to having the control socket feature working on Debian;
  and fixes a variety of smaller bugs.

  o Major bugfixes:
    - Revert the UseBridges option to its behavior before 0.2.2.28-beta.
      When we changed the default behavior to "use bridges if any
      are listed in the torrc", we surprised users who had bridges
      in their torrc files but who didn't actually want to use them.
      Partial resolution for bug 3354.

  o Privacy fixes:
    - Don't attach new streams to old rendezvous circuits after SIGNAL
      NEWNYM. Previously, we would keep using an existing rendezvous
      circuit if it remained open (i.e. if it were kept open by a
      long-lived stream, or if a new stream were attached to it before
      Tor could notice that it was old and no longer in use). Bugfix on
      0.1.1.15-rc; fixes bug 3375.

  o Minor bugfixes:
    - Fix a bug when using ControlSocketsGroupWritable with User. The
      directory's group would be checked against the current group, not
      the configured group. Patch by Jérémy Bobbio. Fixes bug 3393;
      bugfix on 0.2.2.26-beta.
    - Make connection_printf_to_buf()'s behavior sane. Its callers
      expect it to emit a CRLF iff the format string ends with CRLF;
      it actually emitted a CRLF iff (a) the format string ended with
      CRLF or (b) the resulting string was over 1023 characters long or
      (c) the format string did not end with CRLF *and* the resulting
      string was 1021 characters long or longer. Bugfix on 0.1.1.9-alpha;
      fixes part of bug 3407.
    - Make send_control_event_impl()'s behavior sane. Its callers
      expect it to always emit a CRLF at the end of the string; it
      might have emitted extra control characters as well. Bugfix on
      0.1.1.9-alpha; fixes another part of bug 3407.
    - Make crypto_rand_int() check the value of its input correctly.
      Previously, it accepted values up to UINT_MAX, but could return a
      negative number if given a value above INT_MAX+1. Found by George
      Kadianakis. Fixes bug 3306; bugfix on 0.2.2pre14.
    - Avoid a segfault when reading a malformed circuit build state
      with more than INT_MAX entries. Found by wanoskarnet. Bugfix on
      0.2.2.4-alpha.
    - When asked about a DNS record type we don't support via a
      client DNSPort, reply with NOTIMPL rather than an empty
      reply. Patch by intrigeri. Fixes bug 3369; bugfix on 2.0.1-alpha.
    - Fix a rare memory leak during stats writing. Found by coverity.

  o Minor features:
    - Update to the June 1 2011 Maxmind GeoLite Country database.

  o Code simplifications and refactoring:
    - Remove some dead code as indicated by coverity.
    - Remove a few dead assignments during router parsing. Found by
      coverity.
    - Add some forgotten return value checks during unit tests. Found
      by coverity.
    - Don't use 1-bit wide signed bit fields. Found by coverity.


Changes in version 0.2.2.28-beta - 2011-06-04
  Tor 0.2.2.28-beta makes great progress towards a new stable release: we
  fixed a big bug in whether relays stay in the consensus consistently,
  we moved closer to handling bridges and hidden services correctly,
  and we started the process of better handling the dreaded "my Vidalia
  died, and now my Tor demands a password when I try to reconnect to it"
  usability issue.

  o Major bugfixes:
    - Don't decide to make a new descriptor when receiving a HUP signal.
      This bug has caused a lot of 0.2.2.x relays to disappear from the
      consensus periodically. Fixes the most common case of triggering
      bug 1810; bugfix on 0.2.2.7-alpha.
    - Actually allow nameservers with IPv6 addresses. Fixes bug 2574.
    - Don't try to build descriptors if "ORPort auto" is set and we
      don't know our actual ORPort yet. Fix for bug 3216; bugfix on
      0.2.2.26-beta.
    - Resolve a crash that occurred when setting BridgeRelay to 1 with
      accounting enabled. Fixes bug 3228; bugfix on 0.2.2.18-alpha.
    - Apply circuit timeouts to opened hidden-service-related circuits
      based on the correct start time. Previously, we would apply the
      circuit build timeout based on time since the circuit's creation;
      it was supposed to be applied based on time since the circuit
      entered its current state. Bugfix on 0.0.6; fixes part of bug 1297.
    - Use the same circuit timeout for client-side introduction
      circuits as for other four-hop circuits, rather than the timeout
      for single-hop directory-fetch circuits; the shorter timeout may
      have been appropriate with the static circuit build timeout in
      0.2.1.x and earlier, but caused many hidden service access attempts
      to fail with the adaptive CBT introduced in 0.2.2.2-alpha. Bugfix
      on 0.2.2.2-alpha; fixes another part of bug 1297.
    - In ticket 2511 we fixed a case where you could use an unconfigured
      bridge if you had configured it as a bridge the last time you ran
      Tor. Now fix another edge case: if you had configured it as a bridge
      but then switched to a different bridge via the controller, you
      would still be willing to use the old one. Bugfix on 0.2.0.1-alpha;
      fixes bug 3321.

  o Major features:
    - Add an __OwningControllerProcess configuration option and a
      TAKEOWNERSHIP control-port command. Now a Tor controller can ensure
      that when it exits, Tor will shut down. Implements feature 3049.
    - If "UseBridges 1" is set and no bridges are configured, Tor will
      now refuse to build any circuits until some bridges are set.
      If "UseBridges auto" is set, Tor will use bridges if they are
      configured and we are not running as a server, but otherwise will
      make circuits as usual. The new default is "auto". Patch by anonym,
      so the Tails LiveCD can stop automatically revealing you as a Tor
      user on startup.

  o Minor bugfixes:
    - Fix warnings from GCC 4.6's "-Wunused-but-set-variable" option.
    - Remove a trailing asterisk from "exit-policy/default" in the
      output of the control port command "GETINFO info/names". Bugfix
      on 0.1.2.5-alpha.
    - Use a wide type to hold sockets when built for 64-bit Windows builds.
      Fixes bug 3270.
    - Warn when the user configures two HiddenServiceDir lines that point
      to the same directory. Bugfix on 0.0.6 (the version introducing
      HiddenServiceDir); fixes bug 3289.
    - Remove dead code from rend_cache_lookup_v2_desc_as_dir. Fixes
      part of bug 2748; bugfix on 0.2.0.10-alpha.
    - Log malformed requests for rendezvous descriptors as protocol
      warnings, not warnings. Also, use a more informative log message
      in case someone sees it at log level warning without prior
      info-level messages. Fixes the other part of bug 2748; bugfix
      on 0.2.0.10-alpha.
    - Clear the table recording the time of the last request for each
      hidden service descriptor from each HS directory on SIGNAL NEWNYM.
      Previously, we would clear our HS descriptor cache on SIGNAL
      NEWNYM, but if we had previously retrieved a descriptor (or tried
      to) from every directory responsible for it, we would refuse to
      fetch it again for up to 15 minutes. Bugfix on 0.2.2.25-alpha;
      fixes bug 3309.
    - Fix a log message that said "bits" while displaying a value in
      bytes. Found by wanoskarnet. Fixes bug 3318; bugfix on
      0.2.0.1-alpha.
    - When checking for 1024-bit keys, check for 1024 bits, not 128
      bytes. This allows Tor to correctly discard keys of length 1017
      through 1023. Bugfix on 0.0.9pre5.

  o Minor features:
    - Relays now log the reason for publishing a new relay descriptor,
      so we have a better chance of hunting down instances of bug 1810.
      Resolves ticket 3252.
    - Revise most log messages that refer to nodes by nickname to
      instead use the "$key=nickname at address" format. This should be
      more useful, especially since nicknames are less and less likely
      to be unique. Resolves ticket 3045.
    - Log (at info level) when purging pieces of hidden-service-client
      state because of SIGNAL NEWNYM.

  o Removed options:
    - Remove undocumented option "-F" from tor-resolve: it hasn't done
      anything since 0.2.1.16-rc.


Changes in version 0.2.2.27-beta - 2011-05-18
  Tor 0.2.2.27-beta fixes a bridge-related stability bug in the previous
  release, and also adds a few more general bugfixes.

  o Major bugfixes:
    - Fix a crash bug when changing bridges in a running Tor process.
      Fixes bug 3213; bugfix on 0.2.2.26-beta.
    - When the controller configures a new bridge, don't wait 10 to 60
      seconds before trying to fetch its descriptor. Bugfix on
      0.2.0.3-alpha; fixes bug 3198 (suggested by 2355).

  o Minor bugfixes:
    - Require that onion keys have exponent 65537 in microdescriptors too.
      Fixes more of bug 3207; bugfix on 0.2.2.26-beta.
    - Tor used to limit HttpProxyAuthenticator values to 48 characters.
      Changed the limit to 512 characters by removing base64 newlines.
      Fixes bug 2752. Fix by Michael Yakubovich.
    - When a client starts or stops using bridges, never use a circuit
      that was built before the configuration change. This behavior could
      put at risk a user who uses bridges to ensure that her traffic
      only goes to the chosen addresses. Bugfix on 0.2.0.3-alpha; fixes
      bug 3200.


Changes in version 0.2.2.26-beta - 2011-05-17
  Tor 0.2.2.26-beta fixes a variety of potential privacy problems. It
  also introduces a new "socksport auto" approach that should make it
  easier to run multiple Tors on the same system, and does a lot of
  cleanup to get us closer to a release candidate.

  o Security/privacy fixes:
    - Replace all potentially sensitive memory comparison operations
      with versions whose runtime does not depend on the data being
      compared. This will help resist a class of attacks where an
      adversary can use variations in timing information to learn
      sensitive data. Fix for one case of bug 3122. (Safe memcmp
      implementation by Robert Ransom based partially on code by DJB.)
    - When receiving a hidden service descriptor, check that it is for
      the hidden service we wanted. Previously, Tor would store any
      hidden service descriptors that a directory gave it, whether it
      wanted them or not. This wouldn't have let an attacker impersonate
      a hidden service, but it did let directories pre-seed a client
      with descriptors that it didn't want. Bugfix on 0.0.6.
    - On SIGHUP, do not clear out all TrackHostExits mappings, client
      DNS cache entries, and virtual address mappings: that's what
      NEWNYM is for. Fixes bug 1345; bugfix on 0.1.0.1-rc.

  o Major features:
    - The options SocksPort, ControlPort, and so on now all accept a
      value "auto" that opens a socket on an OS-selected port. A
      new ControlPortWriteToFile option tells Tor to write its
      actual control port or ports to a chosen file. If the option
      ControlPortFileGroupReadable is set, the file is created as
      group-readable. Now users can run two Tor clients on the same
      system without needing to manually mess with parameters. Resolves
      part of ticket 3076.
    - Set SO_REUSEADDR on all sockets, not just listeners. This should
      help busy exit nodes avoid running out of useable ports just
      because all the ports have been used in the near past. Resolves
      issue 2850.

  o Minor features:
    - New "GETINFO net/listeners/(type)" controller command to return
      a list of addresses and ports that are bound for listeners for a
      given connection type. This is useful when the user has configured
      "SocksPort auto" and the controller needs to know which port got
      chosen. Resolves another part of ticket 3076.
    - Add a new ControlSocketsGroupWritable configuration option: when
      it is turned on, ControlSockets are group-writeable by the default
      group of the current user. Patch by Jérémy Bobbio; implements
      ticket 2972.
    - Tor now refuses to create a ControlSocket in a directory that is
      world-readable (or group-readable if ControlSocketsGroupWritable
      is 0). This is necessary because some operating systems do not
      enforce permissions on an AF_UNIX sockets. Permissions on the
      directory holding the socket, however, seems to work everywhere.
    - Rate-limit a warning about failures to download v2 networkstatus
      documents. Resolves part of bug 1352.
    - Backport code from 0.2.3.x that allows directory authorities to
      clean their microdescriptor caches. Needed to resolve bug 2230.
    - When an HTTPS proxy reports "403 Forbidden", we now explain
      what it means rather than calling it an unexpected status code.
      Closes bug 2503. Patch from Michael Yakubovich.
    - Update to the May 1 2011 Maxmind GeoLite Country database.

  o Minor bugfixes:
    - Authorities now clean their microdesc cache periodically and when
      reading from disk initially, not only when adding new descriptors.
      This prevents a bug where we could lose microdescriptors. Bugfix
      on 0.2.2.6-alpha. Fixes bug 2230.
    - Do not crash when our configuration file becomes unreadable, for
      example due to a permissions change, between when we start up
      and when a controller calls SAVECONF. Fixes bug 3135; bugfix
      on 0.0.9pre6.
    - Avoid a bug that would keep us from replacing a microdescriptor
      cache on Windows. (We would try to replace the file while still
      holding it open. That's fine on Unix, but Windows doesn't let us
      do that.) Bugfix on 0.2.2.6-alpha; bug found by wanoskarnet.
    - Add missing explanations for the authority-related torrc options
      RephistTrackTime, BridgePassword, and V3AuthUseLegacyKey in the
      man page. Resolves issue 2379.
    - As an authority, do not upload our own vote or signature set to
      ourself. It would tell us nothing new, and as of 0.2.2.24-alpha,
      it would get flagged as a duplicate. Resolves bug 3026.
    - Accept hidden service descriptors if we think we might be a hidden
      service directory, regardless of what our consensus says. This
      helps robustness, since clients and hidden services can sometimes
      have a more up-to-date view of the network consensus than we do,
      and if they think that the directory authorities list us a HSDir,
      we might actually be one. Related to bug 2732; bugfix on
      0.2.0.10-alpha.
    - When a controller changes TrackHostExits, remove mappings for
      hosts that should no longer have their exits tracked. Bugfix on
      0.1.0.1-rc.
    - When a controller changes VirtualAddrNetwork, remove any mappings
      for hosts that were automapped to the old network. Bugfix on
      0.1.1.19-rc.
    - When a controller changes one of the AutomapHosts* options, remove
      any mappings for hosts that should no longer be automapped. Bugfix
      on 0.2.0.1-alpha.
    - Do not reset the bridge descriptor download status every time we
      re-parse our configuration or get a configuration change. Fixes
      bug 3019; bugfix on 0.2.0.3-alpha.

  o Minor bugfixes (code cleanup):
    - When loading the microdesc journal, remember its current size.
      In 0.2.2, this helps prevent the microdesc journal from growing
      without limit on authorities (who are the only ones to use it in
      0.2.2). Fixes a part of bug 2230; bugfix on 0.2.2.6-alpha.
      Fix posted by "cypherpunks."
    - The microdesc journal is supposed to get rebuilt only if it is
      at least _half_ the length of the store, not _twice_ the length
      of the store. Bugfix on 0.2.2.6-alpha; fixes part of bug 2230.
    - Fix a potential null-pointer dereference while computing a
      consensus. Bugfix on 0.2.0.3-alpha, found with the help of
      clang's analyzer.
    - Avoid a possible null-pointer dereference when rebuilding the mdesc
      cache without actually having any descriptors to cache. Bugfix on
      0.2.2.6-alpha. Issue discovered using clang's static analyzer.
    - If we fail to compute the identity digest of a v3 legacy keypair,
      warn, and don't use a buffer-full of junk instead. Bugfix on
      0.2.1.1-alpha; fixes bug 3106.
    - Resolve an untriggerable issue in smartlist_string_num_isin(),
      where if the function had ever in the future been used to check
      for the presence of a too-large number, it would have given an
      incorrect result. (Fortunately, we only used it for 16-bit
      values.) Fixes bug 3175; bugfix on 0.1.0.1-rc.
    - Require that introduction point keys and onion handshake keys
      have a public exponent of 65537. Starts to fix bug 3207; bugfix
      on 0.2.0.10-alpha.

  o Removed features:
    - Caches no longer download and serve v2 networkstatus documents
      unless FetchV2Networkstatus flag is set: these documents haven't
      haven't been used by clients or relays since 0.2.0.x. Resolves
      bug 3022.


Changes in version 0.2.3.1-alpha - 2011-05-05
  Tor 0.2.3.1-alpha adds some new experimental features, including support
  for an improved network IO backend, IOCP networking on Windows,
  microdescriptor caching, "fast-start" support for streams, and automatic
  home router configuration. There are also numerous internal improvements
  to try to make the code easier for developers to work with.

  This is the first alpha release in a new series, so expect there to be
  bugs. Users who would rather test out a more stable branch should
  stay with 0.2.2.x for now.

  o Major features:
    - Tor can now optionally build with the "bufferevents" buffered IO
      backend provided by Libevent 2. To use this feature, make sure you
      have the latest possible version of Libevent, and pass the
      --enable-bufferevents flag to configure when building Tor from
      source. This feature will make our networking code more flexible,
      let us stack layers on each other, and let us use more efficient
      zero-copy transports where available.
    - As an experimental feature, Tor can use IOCP for networking on Windows.
      Once this code is tuned and optimized, it promises much better
      performance than the select-based backend we've used in the past. To
      try this feature, you must build Tor with Libevent 2, configure Tor
      with the "bufferevents" buffered IO backend, and add "DisableIOCP 0" to
      your torrc. There are known bugs here: only try this if you can help
      debug it as it breaks.
    - The EntryNodes option can now include country codes like {de} or IP
      addresses or network masks. Previously we had disallowed these options
      because we didn't have an efficient way to keep the list up to
      date. Fixes bug 1982, but see bug 2798 for an unresolved issue here.
    - Exit nodes now accept and queue data on not-yet-connected streams.
      Previously, the client wasn't allowed to send data until the stream was
      connected, which slowed down all connections. This change will enable
      clients to perform a "fast-start" on streams and send data without
      having to wait for a confirmation that the stream has opened. (Patch
      from Ian Goldberg; implements the server side of Proposal 174.)
    - Tor now has initial support for automatic port mapping on the many
      home routers that support NAT-PMP or UPnP. (Not yet supported on
      Windows). To build the support code, you'll need to have libnatpnp
      library and/or the libminiupnpc library, and you'll need to enable the
      feature specifically by passing "--enable-upnp" and/or
      "--enable-natpnp" to configure. To turn it on, use the new
      PortForwarding option.
    - Caches now download, cache, and serve multiple "flavors" of the
      consensus, including a flavor that describes microdescriptors.
    - Caches now download, cache, and serve microdescriptors -- small
      summaries of router descriptors that are authenticated by all of the
      directory authorities. Once enough caches are running this code,
      clients will be able to save significant amounts of directory bandwidth
      by downloading microdescriptors instead of router descriptors.

  o Minor features:
    - Make logging resolution configurable with a new LogTimeGranularity
      option, and change the default from 1 millisecond to 1 second.
      Implements enhancement 1668.
    - We log which torrc file we're using on startup. Implements ticket
      2444.
    - Ordinarily, Tor does not count traffic from private addresses (like
      127.0.0.1 or 10.0.0.1) when calculating rate limits or accounting.
      There is now a new option, CountPrivateBandwidth, to disable this
      behavior. Patch from Daniel Cagara.
    - New --enable-static-tor configure option for building Tor as
      statically as possible. Idea, general hackery and thoughts from
      Alexei Czeskis, John Gilmore, Jacob Appelbaum. Implements ticket
      2702.
    - If you set the NumCPUs option to 0, Tor will now try to detect how
      many CPUs you have. This is the new default behavior.
    - Turn on directory request statistics by default and include them in
      extra-info descriptors. Don't break if we have no GeoIP database.
    - Relays that set "ConnDirectionStatistics 1" write statistics on the
      bidirectional use of connections to disk every 24 hours.
    - Add a GeoIP file digest to the extra-info descriptor. Implements
      enhancement 1883.
    - The NodeFamily option -- which let you declare that you want to
      consider nodes to be part of a family whether they list themselves
      that way or not -- now allows IP address ranges and country codes.
    - Add a new 'Heartbeat' log message type to periodically log a message
      describing Tor's status at level Notice. This feature is meant for
      operators who log at notice, and want to make sure that their Tor
      server is still working. Implementation by George Kadianakis.

  o Minor bugfixes (on 0.2.2.25-alpha):
    - When loading the microdesc journal, remember its current size.
      In 0.2.2, this helps prevent the microdesc journal from growing
      without limit on authorities (who are the only ones to use it in
      0.2.2). Fixes a part of bug 2230; bugfix on 0.2.2.6-alpha.
      Fix posted by "cypherpunks."
    - The microdesc journal is supposed to get rebuilt only if it is
      at least _half_ the length of the store, not _twice_ the length
      of the store. Bugfix on 0.2.2.6-alpha; fixes part of bug 2230.
    - If as an authority we fail to compute the identity digest of a v3
      legacy keypair, warn, and don't use a buffer-full of junk instead.
      Bugfix on 0.2.1.1-alpha; fixes bug 3106.
    - Authorities now clean their microdesc cache periodically and when
      reading from disk initially, not only when adding new descriptors.
      This prevents a bug where we could lose microdescriptors. Bugfix
      on 0.2.2.6-alpha.

  o Minor features (controller):
    - Add a new SIGNAL event to the controller interface so that
      controllers can be notified when Tor handles a signal. Resolves
      issue 1955. Patch by John Brooks.
    - Add a new GETINFO option to get total bytes read and written. Patch
      from pipe, revised by atagar. Resolves ticket 2345.
    - Implement some GETINFO controller fields to provide information about
      the Tor process's pid, euid, username, and resource limits.

  o Build changes:
    - Our build system requires automake 1.6 or later to create the
      Makefile.in files. Previously, you could have used 1.4.
      This only affects developers and people building Tor from git;
      people who build Tor from the source distribution without changing
      the Makefile.am files should be fine.
    - Our autogen.sh script uses autoreconf to launch autoconf, automake, and
      so on. This is more robust against some of the failure modes
      associated with running the autotools pieces on their own.

  o Minor packaging issues:
    - On OpenSUSE, create the /var/run/tor directory on startup if it is not
      already created. Patch from Andreas Stieger. Fixes bug 2573.

  o Code simplifications and refactoring:
    - A major revision to our internal node-selecting and listing logic.
      Tor already had at least two major ways to look at the question of
      "which Tor servers do we know about": a list of router descriptors,
      and a list of entries in the current consensus. With
      microdescriptors, we're adding a third. Having so many systems
      without an abstraction layer over them was hurting the codebase.
      Now, we have a new "node_t" abstraction that presents a consistent
      interface to a client's view of a Tor node, and holds (nearly) all
      of the mutable state formerly in routerinfo_t and routerstatus_t.
    - The helper programs tor-gencert, tor-resolve, and tor-checkkey
      no longer link against Libevent: they never used it, but
      our library structure used to force them to link it.

  o Removed features:
    - Remove some old code to work around even older versions of Tor that
      used forked processes to handle DNS requests. Such versions of Tor
      are no longer in use as servers.

  o Documentation fixes:
    - Correct a broken faq link in the INSTALL file. Fixes bug 2307.
    - Add missing documentation for the authority-related torrc options
      RephistTrackTime, BridgePassword, and V3AuthUseLegacyKey. Resolves
      issue 2379.


Changes in version 0.2.2.25-alpha - 2011-04-29
  Tor 0.2.2.25-alpha fixes many bugs: hidden service clients are more
  robust, routers no longer overreport their bandwidth, Win7 should crash
  a little less, and NEWNYM (as used by Vidalia's "new identity" button)
  now prevents hidden service-related activity from being linkable. It
  provides more information to Vidalia so you can see if your bridge is
  working. Also, 0.2.2.25-alpha revamps the Entry/Exit/ExcludeNodes and
  StrictNodes configuration options to make them more reliable, more
  understandable, and more regularly applied. If you use those options,
  please see the revised documentation for them in the manual page.

  o Major bugfixes:
    - Relays were publishing grossly inflated bandwidth values because
      they were writing their state files wrong--now they write the
      correct value. Also, resume reading bandwidth history from the
      state file correctly. Fixes bug 2704; bugfix on 0.2.2.23-alpha.
    - Improve hidden service robustness: When we find that we have
      extended a hidden service's introduction circuit to a relay not
      listed as an introduction point in the HS descriptor we currently
      have, retry with an introduction point from the current
      descriptor. Previously we would just give up. Fixes bugs 1024 and
      1930; bugfix on 0.2.0.10-alpha.
    - Clients now stop trying to use an exit node associated with a given
      destination by TrackHostExits if they fail to reach that exit node.
      Fixes bug 2999. Bugfix on 0.2.0.20-rc.
    - Fix crash bug on platforms where gmtime and localtime can return
      NULL. Windows 7 users were running into this one. Fixes part of bug
      2077. Bugfix on all versions of Tor. Found by boboper.

  o Security and stability fixes:
    - Don't double-free a parsable, but invalid, microdescriptor, even if
      it is followed in the blob we're parsing by an unparsable
      microdescriptor. Fixes an issue reported in a comment on bug 2954.
      Bugfix on 0.2.2.6-alpha; fix by "cypherpunks".
    - If the Nickname configuration option isn't given, Tor would pick a
      nickname based on the local hostname as the nickname for a relay.
      Because nicknames are not very important in today's Tor and the
      "Unnamed" nickname has been implemented, this is now problematic
      behavior: It leaks information about the hostname without being
      useful at all. Fixes bug 2979; bugfix on 0.1.2.2-alpha, which
      introduced the Unnamed nickname. Reported by tagnaq.
    - Fix an uncommon assertion failure when running with DNSPort under
      heavy load. Fixes bug 2933; bugfix on 0.2.0.1-alpha.
    - Avoid linkability based on cached hidden service descriptors: forget
      all hidden service descriptors cached as a client when processing a
      SIGNAL NEWNYM command. Fixes bug 3000; bugfix on 0.0.6.

  o Major features:
    - Export GeoIP information on bridge usage to controllers even if we
      have not yet been running for 24 hours. Now Vidalia bridge operators
      can get more accurate and immediate feedback about their
      contributions to the network.

  o Major features and bugfixes (node selection):
    - Revise and reconcile the meaning of the ExitNodes, EntryNodes,
      ExcludeEntryNodes, ExcludeExitNodes, ExcludeNodes, and StrictNodes
      options. Previously, we had been ambiguous in describing what
      counted as an "exit" node, and what operations exactly "StrictNodes
      0" would permit. This created confusion when people saw nodes built
      through unexpected circuits, and made it hard to tell real bugs from
      surprises. Now the intended behavior is:
        . "Exit", in the context of ExitNodes and ExcludeExitNodes, means
          a node that delivers user traffic outside the Tor network.
        . "Entry", in the context of EntryNodes, means a node used as the
          first hop of a multihop circuit. It doesn't include direct
          connections to directory servers.
        . "ExcludeNodes" applies to all nodes.
        . "StrictNodes" changes the behavior of ExcludeNodes only. When
          StrictNodes is set, Tor should avoid all nodes listed in
          ExcludeNodes, even when it will make user requests fail. When
          StrictNodes is *not* set, then Tor should follow ExcludeNodes
          whenever it can, except when it must use an excluded node to
          perform self-tests, connect to a hidden service, provide a
          hidden service, fulfill a .exit request, upload directory
          information, or fetch directory information.
      Collectively, the changes to implement the behavior fix bug 1090.
    - ExcludeNodes now takes precedence over EntryNodes and ExitNodes: if
      a node is listed in both, it's treated as excluded.
    - ExcludeNodes now applies to directory nodes -- as a preference if
      StrictNodes is 0, or an absolute requirement if StrictNodes is 1.
      Don't exclude all the directory authorities and set StrictNodes to 1
      unless you really want your Tor to break.
    - ExcludeNodes and ExcludeExitNodes now override exit enclaving.
    - ExcludeExitNodes now overrides .exit requests.
    - We don't use bridges listed in ExcludeNodes.
    - When StrictNodes is 1:
       . We now apply ExcludeNodes to hidden service introduction points
         and to rendezvous points selected by hidden service users. This
         can make your hidden service less reliable: use it with caution!
       . If we have used ExcludeNodes on ourself, do not try relay
         reachability self-tests.
       . If we have excluded all the directory authorities, we will not
         even try to upload our descriptor if we're a relay.
       . Do not honor .exit requests to an excluded node.
    - Remove a misfeature that caused us to ignore the Fast/Stable flags
      when ExitNodes is set. Bugfix on 0.2.2.7-alpha.
    - When the set of permitted nodes changes, we now remove any mappings
      introduced via TrackExitHosts to now-excluded nodes. Bugfix on
      0.1.0.1-rc.
    - We never cannibalize a circuit that had excluded nodes on it, even
      if StrictNodes is 0. Bugfix on 0.1.0.1-rc.
    - Revert a change where we would be laxer about attaching streams to
      circuits than when building the circuits. This was meant to prevent
      a set of bugs where streams were never attachable, but our improved
      code here should make this unnecessary. Bugfix on 0.2.2.7-alpha.
    - Keep track of how many times we launch a new circuit to handle a
      given stream. Too many launches could indicate an inconsistency
      between our "launch a circuit to handle this stream" logic and our
      "attach this stream to one of the available circuits" logic.
    - Improve log messages related to excluded nodes.

  o Minor bugfixes:
    - Fix a spurious warning when moving from a short month to a long
      month on relays with month-based BandwidthAccounting. Bugfix on
      0.2.2.17-alpha; fixes bug 3020.
    - When a client finds that an origin circuit has run out of 16-bit
      stream IDs, we now mark it as unusable for new streams. Previously,
      we would try to close the entire circuit. Bugfix on 0.0.6.
    - Add a forgotten cast that caused a compile warning on OS X 10.6.
      Bugfix on 0.2.2.24-alpha.
    - Be more careful about reporting the correct error from a failed
      connect() system call. Under some circumstances, it was possible to
      look at an incorrect value for errno when sending the end reason.
      Bugfix on 0.1.0.1-rc.
    - Correctly handle an "impossible" overflow cases in connection byte
      counting, where we write or read more than 4GB on an edge connection
      in a single second. Bugfix on 0.1.2.8-beta.
    - Correct the warning displayed when a rendezvous descriptor exceeds
      the maximum size. Fixes bug 2750; bugfix on 0.2.1.5-alpha. Found by
      John Brooks.
    - Clients and hidden services now use HSDir-flagged relays for hidden
      service descriptor downloads and uploads even if the relays have no
      DirPort set and the client has disabled TunnelDirConns. This will
      eventually allow us to give the HSDir flag to relays with no
      DirPort. Fixes bug 2722; bugfix on 0.2.1.6-alpha.
    - Downgrade "no current certificates known for authority" message from
      Notice to Info. Fixes bug 2899; bugfix on 0.2.0.10-alpha.
    - Make the SIGNAL DUMP control-port command work on FreeBSD. Fixes bug
      2917. Bugfix on 0.1.1.1-alpha.
    - Only limit the lengths of single HS descriptors, even when multiple
      HS descriptors are published to an HSDir relay in a single POST
      operation. Fixes bug 2948; bugfix on 0.2.1.5-alpha. Found by hsdir.
    - Write the current time into the LastWritten line in our state file,
      rather than the time from the previous write attempt. Also, stop
      trying to use a time of -1 in our log statements. Fixes bug 3039;
      bugfix on 0.2.2.14-alpha.
    - Be more consistent in our treatment of file system paths. "~" should
      get expanded to the user's home directory in the Log config option.
      Fixes bug 2971; bugfix on 0.2.0.1-alpha, which introduced the
      feature for the -f and --DataDirectory options.

  o Minor features:
    - Make sure every relay writes a state file at least every 12 hours.
      Previously, a relay could go for weeks without writing its state
      file, and on a crash could lose its bandwidth history, capacity
      estimates, client country statistics, and so on. Addresses bug 3012.
    - Send END_STREAM_REASON_NOROUTE in response to EHOSTUNREACH errors.
      Clients before 0.2.1.27 didn't handle NOROUTE correctly, but such
      clients are already deprecated because of security bugs.
    - Don't allow v0 hidden service authorities to act as clients.
      Required by fix for bug 3000.
    - Ignore SIGNAL NEWNYM commands on relay-only Tor instances. Required
      by fix for bug 3000.
    - Ensure that no empty [dirreq-](read|write)-history lines are added
      to an extrainfo document. Implements ticket 2497.

  o Code simplification and refactoring:
    - Remove workaround code to handle directory responses from servers
      that had bug 539 (they would send HTTP status 503 responses _and_
      send a body too). Since only server versions before
      0.2.0.16-alpha/0.1.2.19 were affected, there is no longer reason to
      keep the workaround in place.
    - Remove the old 'fuzzy time' logic. It was supposed to be used for
      handling calculations where we have a known amount of clock skew and
      an allowed amount of unknown skew. But we only used it in three
      places, and we never adjusted the known/unknown skew values. This is
      still something we might want to do someday, but if we do, we'll
      want to do it differently.
    - Avoid signed/unsigned comparisons by making SIZE_T_CEILING unsigned.
      None of the cases where we did this before were wrong, but by making
      this change we avoid warnings. Fixes bug 2475; bugfix on 0.2.1.28.
    - Use GetTempDir to find the proper temporary directory location on
      Windows when generating temporary files for the unit tests. Patch by
      Gisle Vanem.


Changes in version 0.2.2.24-alpha - 2011-04-08
  Tor 0.2.2.24-alpha fixes a variety of bugs, including a big bug that
  prevented Tor clients from effectively using "multihomed" bridges,
  that is, bridges that listen on multiple ports or IP addresses so users
  can continue to use some of their addresses even if others get blocked.

  o Major bugfixes:
    - Fix a bug where bridge users who configure the non-canonical
      address of a bridge automatically switch to its canonical
      address. If a bridge listens at more than one address, it should be
      able to advertise those addresses independently and any non-blocked
      addresses should continue to work. Bugfix on Tor 0.2.0.x. Fixes
      bug 2510.
    - If you configured Tor to use bridge A, and then quit and
      configured Tor to use bridge B instead, it would happily continue
      to use bridge A if it's still reachable. While this behavior is
      a feature if your goal is connectivity, in some scenarios it's a
      dangerous bug. Bugfix on Tor 0.2.0.1-alpha; fixes bug 2511.
    - Directory authorities now use data collected from their own
      uptime observations when choosing whether to assign the HSDir flag
      to relays, instead of trusting the uptime value the relay reports in
      its descriptor. This change helps prevent an attack where a small
      set of nodes with frequently-changing identity keys can blackhole
      a hidden service. (Only authorities need upgrade; others will be
      fine once they do.) Bugfix on 0.2.0.10-alpha; fixes bug 2709.

  o Minor bugfixes:
    - When we restart our relay, we might get a successful connection
      from the outside before we've started our reachability tests,
      triggering a warning: "ORPort found reachable, but I have no
      routerinfo yet. Failing to inform controller of success." This
      bug was harmless unless Tor is running under a controller
      like Vidalia, in which case the controller would never get a
      REACHABILITY_SUCCEEDED status event. Bugfix on 0.1.2.6-alpha;
      fixes bug 1172.
    - Make directory authorities more accurate at recording when
      relays that have failed several reachability tests became
      unreachable, so we can provide more accuracy at assigning Stable,
      Guard, HSDir, etc flags. Bugfix on 0.2.0.6-alpha. Resolves bug 2716.
    - Fix an issue that prevented static linking of libevent on
      some platforms (notably Linux). Fixes bug 2698; bugfix on
      versions 0.2.1.23/0.2.2.8-alpha (the versions introducing
      the --with-static-libevent configure option).
    - We now ask the other side of a stream (the client or the exit)
      for more data on that stream when the amount of queued data on
      that stream dips low enough. Previously, we wouldn't ask the
      other side for more data until either it sent us more data (which
      it wasn't supposed to do if it had exhausted its window!) or we
      had completely flushed all our queued data. This flow control fix
      should improve throughput. Fixes bug 2756; bugfix on the earliest
      released versions of Tor (svn commit r152).
    - Avoid a double-mark-for-free warning when failing to attach a
      transparent proxy connection. (We thought we had fixed this in
      0.2.2.23-alpha, but it turns out our fix was checking the wrong
      connection.) Fixes bug 2757; bugfix on 0.1.2.1-alpha (the original
      bug) and 0.2.2.23-alpha (the incorrect fix).
    - When warning about missing zlib development packages during compile,
      give the correct package names. Bugfix on 0.2.0.1-alpha.

  o Minor features:
    - Directory authorities now log the source of a rejected POSTed v3
      networkstatus vote.
    - Make compilation with clang possible when using
      --enable-gcc-warnings by removing two warning options that clang
      hasn't implemented yet and by fixing a few warnings. Implements
      ticket 2696.
    - When expiring circuits, use microsecond timers rather than
      one-second timers. This can avoid an unpleasant situation where a
      circuit is launched near the end of one second and expired right
      near the beginning of the next, and prevent fluctuations in circuit
      timeout values.
    - Use computed circuit-build timeouts to decide when to launch
      parallel introduction circuits for hidden services. (Previously,
      we would retry after 15 seconds.)
    - Update to the April 1 2011 Maxmind GeoLite Country database.

  o Packaging fixes:
    - Create the /var/run/tor directory on startup on OpenSUSE if it is
      not already created. Patch from Andreas Stieger. Fixes bug 2573.

  o Documentation changes:
    - Modernize the doxygen configuration file slightly. Fixes bug 2707.
    - Resolve all doxygen warnings except those for missing documentation.
      Fixes bug 2705.
    - Add doxygen documentation for more functions, fields, and types.


Changes in version 0.2.2.23-alpha - 2011-03-08
  Tor 0.2.2.23-alpha lets relays record their bandwidth history so when
  they restart they don't lose their bandwidth capacity estimate. This
  release also fixes a diverse set of user-facing bugs, ranging from
  relays overrunning their rate limiting to clients falsely warning about
  clock skew to bridge descriptor leaks by our bridge directory authority.

  o Major bugfixes:
    - Stop sending a CLOCK_SKEW controller status event whenever
      we fetch directory information from a relay that has a wrong clock.
      Instead, only inform the controller when it's a trusted authority
      that claims our clock is wrong. Bugfix on 0.1.2.6-alpha; fixes
      the rest of bug 1074.
    - Fix an assert in parsing router descriptors containing IPv6
      addresses. This one took down the directory authorities when
      somebody tried some experimental code. Bugfix on 0.2.1.3-alpha.
    - Make the bridge directory authority refuse to answer directory
      requests for "all" descriptors. It used to include bridge
      descriptors in its answer, which was a major information leak.
      Found by "piebeer". Bugfix on 0.2.0.3-alpha.
    - If relays set RelayBandwidthBurst but not