tor/doc/TODO

$Id$
Legend:
SPEC!!  - Not specified
SPEC    - Spec not finalized
N       - nick claims
R       - arma claims
P       - phobos claims
S       - Steven claims
M       - Matt/Mike claims
J       - Jeff claims
I       - ioerror claims
W       - weasel claims
        - Not done
        * Top priority
        . Partially done
        o Done
        d Deferrable
        D Deferred
        X Abandoned

=======================================================================

External constraints:

  - Mid Apr
    - More Torbrowser work:
      o Get polipo into it
I     - Figure out who at Mozilla can give us permission to keep the
        name Firefox on our Tor Browser Bundle. Get said permission.
      o Make Torbrowser website
      o Get it integrated into the Tor download pages
S   - Finish first cut at integrating upnp lib into Vidalia
R   - get the geoip files onto some bridge relays, and gather stats

  - End of April
S   - Zip-splitting:
      - Document the use of 7-zip to combine fractional files and
        reconstruct them after download.  Host such files.
      - If it's faster to research a self-extracting splitter
        and use it, with simpler documentation, that's obviously fine.
N   - Investigate and start resolving (or declare unresolvable) the ram
      issue for relays. Investigate and document all of, and do at
      least two of:
      o better buffer approaches in Tor
      - better buffer approaches in openssl
      o shipping Tor with its own integrated allocator.
N   - Write a draft research proposal for how to safely collect and
      aggregate some GeoIP data from non-bridge entry nodes, or conclude
      that we don't know how to do it safely while still being useful
      and explain why.
I   - Translation portal
      - Vidalia translations (via launchpad?)
      - Vidalia installer translations
      - Torbutton translations (via babelzilla?)
        o Torbutton is registered with launchpad and babelzilla
        o https://launchpad.net/torbutton
        - An old babelzilla version of Torbutton requires an update
      - Centralized instructions for how to help translate
      - Continue managing the tor-translations team to keep the Tor
        website translated

  - End of May
S   - More TorBrowser work
      - Integrate pidgin and OTR
      - move portablefirefox nsi goo into vidalia as appropriate
      - Figure out (or give up on) how to run Tor Browser and ordinary
        Firefox side-by-side.

  - mid June
R   - SRI stuff

  - mid June
    - More TorBrowser work
S     - Firefox extension framework for Torbrowser build-time
S     - Progress bar during startup, including some "timeout" events to
        indicate when Tor's unlikely to succeed at startup.
R       - Make Tor put out appropriate events
M       - Let Vidalia notice them and change its appearance
S     - Enumerate and analyze traces left when running from USB
R   - Finish tor-doc-bridge.wml
    - More bridgedb work:
R     - Get the dkimproxy patch in
?     - Brainstorm about safe but effective ways for vidalia to
        auto-update its user's bridges via Tor in the background.
NR    - Include "stable" bridge and "port 443" bridge and "adequately
        new version" bridge free in every specially marked
        box!^W^W^Woutput batch.
N     - Detect proxies and treat them as the same address
    - More back-end work:
N     - If we decided above that we know how to collect geoip data for
        non bridge relays, deploy that plan.
N     - Additional TLS-camouflage work (spoofing FF cipher suite, etc.)
        - spoof the cipher suites
        - spoof the extensions list
        - red-team testing (a.k.a, look at a packet dump and compare),
        - investigate the feasibility of handing connections off to a
          local apache if they don't look like Tor or if they don't
          portknock or whatever.
W     - Get closer to downloading far fewer descriptors
        - Instrument the code to track how many descriptors we download vs how
          many times we extend a circuit.
        - Write a proposal for how to fetch far fewer descriptors; assess
          anonymity attacks, like from looking at the size of the
          descriptor you fetch.
I     - Translation portal
        - Torbutton webpage
        o Torbrowser webpage
        - Tor website
        - check.torproject.org
        - should we i18nize polipo's error messages too?

  - August
I   - Auto update
      o Vidalia learns when Tor thinks it should be updated
R     - Tor status events should suggest a new version to switch to
I     - Figure out a good PKI, document the design, assess security issues:
        "write a proposal"
      - Vidalia fetches the new one via Tor when possible, but fetches
        it without Tor "when necessary", whatever that means.
        - Give an interface for notifying the user, and letting her
          decide to fetch and decide to swap out the old Tor for the new.
      - Do the same for Polipo
      - and for Vidalia itself

=======================================================================

Things Roger would be excited to see:

Nick
  - Finish buffer stuff in libevent; start using it in Tor.
  - Tors start believing the contents of NETINFO cells.
  - Get a "use less buffer ram" patch into openssl.

Matt
  - Fit Vidalia in 640x480 again.
  - When user changes the language in Vidalia, have it change right then.
  - Vidalia should display/edit PlaintextPorts events/config.
  . Vidalia's GUI should let you specify an http proxy that it launches
    for you. Maybe in the general config window next to which Tor it
    launches for you.
  - Vidalia should avoid stomping on your custom exit policy lines
    just because you click on 'save' for a totally different config thing.

ioerror
  - gmail auto responder so you send us an email and we send you a Tor
    binary. Probably needs a proposal first.
  - weather.torproject.org should go live.
  - Learn from Steven how to build/maintain the Tor Browser Bundle.
  - Learn from Mike how to run SoaT, and try to make that an automated
    service somewhere.
  - Keep advocating new Tor servers and working with orgs like Mozilla
    to let them like Tor.
  - Start converting critical wiki pages into real Tor wml pages. E.g.,
    https://wiki.torproject.org/noreply/TheOnionRouter/VerifyingSignatures
  - Find out what happened to the buildbot and get it back up:
    http://tor-buildbot.freehaven.net:8010/

Steven
  - Write a list of research items Tor would like to see done, for the
    volunteer page. Pick a few you'd like to work on yourself.
  - Move proposal 131 or equivalent forward.
  - Keep bugging us about exploits on the .exit notation.
  - If relays have 100KB/s but set relaybandwidthrate to 10KB/s, do your
    interference attacks still work?

Andrew
  - Which bundles include Torbutton? Change the docs/tor-doc-foo pages
    so they admit that Torbutton is in them too. Change the download
    page too.
  - The OS X bundle screenshots are from forever ago -- they don't
    include Torbutton, they still say it's tor.eff.org, etc.
  - Should we still be telling you how to use Safari on OS X for Tor,
    given all the holes that Torbutton-dev solves on Firefox?

Karsten
  . Make a hidden services explanation page with the hidden service
    diagrams. See img/THS-[1-6].png. These need some text to go along
    with them though, so people can follow what's going on.
    - Roger should review these
  - We should consider a single config option TorPrivateNetwork that
    turns on all the config options for running a private test tor
    network. having to keep updating all the tools, and the docs,
    just isn't working.

Weasel
  - Figure out how to make Vidalia and Tor play nicely on Debian, make
    the necessary modifications, and make some Vidalia debs that pass
    muster.
  - Fix bug 393.
  - Get oftc to switch to the Tor dns exitlist. Or tell us why it's
    not suitable yet.
  - Take non-Running entries out of the networkstatus consensus.
  - Move proposal 134 forward.

=======================================================================

For Tor 0.2.0.x-rc:
R - Figure out the autoconf problem with adding a fallback consensus.
R - add a geoip file
W   - figure out license
R - let bridges set relaybandwidthrate as low as 5kb
R - bug: if we launch using bridges, and then stop using bridges, we
    still have our bridges in our entryguards section, and may use them.
  . make it easier to set up a private tor network on your own computer
    is very hard.
R   . FAQ entry which is wrong

N . geoip caching and publishing for bridges
    d Track consecutive time up, not time since last-forgotten IP.
    - Mention in dir-spec.txt
    - Mention in control-spec.txt
    D have normal relays report geoip stats too.
    D different thresholds for bridges than for normal relays.
    o bridge relays round geoip stats *up*, not down.
R - bridge communities
    . spec
    . deploy
      - man page entries for Alternate*Authority config options

Things we'd like to do in 0.2.0.x:
N - document the "3/4 and 7/8" business in the clients fetching consensus
    documents timeline.
R   - then document the bridge user download timeline.

N - Before the feature freeze:
    - 105+TLS, if possible.
      . TLS backend work
        . Enable.
      - Test
        o Verify version negotiation on client
        o Verify version negotiation on server
        o Verify that client->server connection becomes open
        - Verify that server->server connection becomes open and
          authenticated.
        - Verify that initiator sends no cert in first stage of TLS
          handshake.
      - NETINFO fallout
        - Don't extend a circuit over a noncanonical connection with
          mismatched address.
        - Learn our outgoing IP address from netinfo cells?

  - Proposals:
    . 111: Prioritize local traffic over relayed.
R     - Merge into tor-spec.txt.
    - 113: close.

=======================================================================

For 0.2.1.x:
  - Proposals to do:
    - 110: avoid infinite-length circuits
    - 128: families of private bridges
    - 134: handle authority fragmentation.

  - Proposals to write:
    - Multilayered guards to keep bridges hidden.
    - Proposal to supersede 117 by adding IPv6 support for exits and entries.
    - Fix voting to handle bug 608 case when multiple servers get
      Named.
    - Possibly: revise link protocol to allow big circuit IDs,
      variable-length cells, proposal-110 stuff, and versioned CREATES?
    - Eliminate use of v2 networkstatus documents in v3 authority
      decision-making.
    - Draft proposal for GeoIP aggregation (see external constraints *)

  - Use less RAM *
  - Handle multi-core cpus better
  - Use information from NETINFO cells
  - Better test coverage
  - Use more mid-level and high-level libevent APIs
  - Emulate NSS better:
    - Normalized cipher lists *
    - Normalized lists of extensions *



Planned for 0.2.1.x:
  - Refactoring:
    . Make cells get buffered on circuit, not on the or_conn.
      . Switch to pool-allocation for cells?
N       - Benchmark pool-allocation vs straightforward malloc.
N       - Adjust memory allocation logic in pools to favor a little less
          slack memory.
    . Remove socketpair-based bridges conns, and the word "bridge".  (Use
      shared (or connected) buffers for communication, rather than sockets.)
      . Implement
N       - Handle rate-limiting on directory writes to linked directory
          connections in a more sensible manner.
          Nick thinks he did this already?
N       - Find more ways to test this.
          (moria doesn't rate limit, so testing on moria not so good.)

  - Documentation
    - HOWTO for DNSPort. See tup's wiki page.
    . Document transport and natdport in a good HOWTO.
N   - Quietly document NT Service options: revise (or create) FAQ entry

P - Make documentation realize that location of system configuration file
    will depend on location of system defaults, and isn't always /etc/torrc.
P - Figure out why dll's compiled in mingw don't work right in WinXP.
P - create a "make win32-bundle" for vidalia-privoxy-tor-torbutton bundle

  - Things that have been bugging Nick
    - Make better use of multi-core machines: Do AES crypto and
      compression in worker threads
    - Maybe use jemalloc from freebsd via firefox 3, once its windows
      and osx ports are more mature.
    - MMap the cached-descriptors.new file as well as the regular ones
    - Actually use SSL_shutdown to close our TLS connections.
    - Refactor the HTTP logic so the functions aren't so large.
    - Get a "use less buffer ram" patch into openssl.
    - Get IOCP patch into libevent
    - Use libevent's evdns code where applicable.
    - Refactor buf_read and buf_write to have sensible ways to return
      error codes after partial writes
    - Improve unit test coverage
    - Logging domains.

  - get rid of the v1 directory stuff (making, serving, and caching).
    - perhaps replace it with a "this is a tor server" stock webpage.
  - the v2dir flag isn't used for anything anymore. right?
  - even clients run rep_hist_load_mtbf_data(). this wastes memory.
  - steven's plan for replacing check.torproject.org with a built-in
    answer by tor itself.
  - a status event for when tor decides to stop fetching directory info
    if the client hasn't clicked recently: then make the onion change too.

  - bridge communities with local bridge authorities:
    - clients who have a password configured decide to ask their bridge
      authority for a networkstatus
    - be able to have bridges that aren't in your torrc. save them in
      state file, etc.
N - router_choose_random_node() has a big pile of args. make it "flags".
  - Consider if we can solve: the Tor client doesn't know what flags
    its bridge has (since it only gets the descriptor), so it can't
    make decisions based on Fast or Stable.
  - anonymity concern: since our is-consensus-fresh-enough check is
    sloppy so clients will actually work when a consensus wasn't formed,
    does that mean that if users are idle for 5 hours and then click on
    something, we will immediately use the old descriptors we've got,
    while we try fetching the newer descriptors?
    related to bug 401.
  . Finish path-spec.txt
  - More prominently, we should have a recommended apps list.
    - recommend pidgin (gaim is renamed)
    - unrecommend IE because of ftp:// bug.
  - we should add a preamble to tor-design saying it's out of date.
  - Refactor networkstatus generation:
    - Include "v" line in getinfo values.
  - config option __ControllerLimit that hangs up if there are a limit
    of controller connections already.
  - Features (other than bridges):
    - Audit how much RAM we're using for buffers and cell pools; try to
      trim down a lot.
    - Base relative control socket paths on datadir.
    - Make TrackHostExits expire TrackHostExitsExpire seconds after their
       *last* use, not their *first* use.
  - switch out privoxy in the bundles and replace it with polipo.
  - Consider creating special Tor-Polipo-Vidalia test packages,
    requested by Dmitri Vitalev (does torbrowser meet this need?)
  - Create packages for Nokia 800, requested by Chris Soghoian
  - mirror tor downloads on (via) tor dir caches
    . spec
    - deploy
  - interface for letting soat modify flags that authorities assign
    . spec
  - proposal 118 if feasible and obvious
  - Maintain a skew estimate and use ftime consistently.
  - Tor logs the libevent version on startup, for debugging purposes.
    This is great. But it does this before configuring the logs, so
    it only goes to stdout and is then lost.
  - Deprecations:
    - can we deprecate 'getinfo network-status'?
    - can we deprecate the FastFirstHopPK config option?
  - Bridges:
    . Bridges users (rudimentary version)
      . Ask all directory questions to bridge via BEGIN_DIR.
        - use the bridges for dir fetches even when our dirport is open.
      - drop 'authority' queries if they're to our own identity key; accept
        them otherwise.
      - give extend_info_t a router_purpose again
  d Limit to 2 dir, 2 OR, N SOCKS connections per IP.
    - Or maybe close connections from same IP when we get a lot from one.
    - Or maybe block IPs that connect too many times at once.
  - Do TLS connection rotation more often than "once a week" in the
    extra-stable case.
  - Streamline how we pick entry nodes: Make choose_random_entry() have
    less magic and less control logic.
  - when somebody uses the controlport as an http proxy, give them
    a "tor isn't an http proxy" error too like we do for the socks port.
  - we try to build 4 test circuits to break them over different
    servers. but sometimes our entry node is the same for multiple
    test circuits. this defeats the point.
  - enforce a lower limit on MaxCircuitDirtiness and CircuitBuildTimeout.
  - configurable timestamp granularity. defaults to 'seconds'.
  - consider making 'safelogging' extend to info-level logs too.
  - consider whether a single Guard flag lets us distinguish between
    "was good enough to be a guard when we picked it" and "is still
    adequate to be used as a guard even after we've picked it". We should
    write a real proposal for this.
  - make the new tls handshake blocking-resistant.
  o figure out some way to collect feedback about what countries are using
    bridges, in a way that doesn't screw anonymity too much.
  - let tor dir mirrors proxy connections to the tor download site, so
    if you know a bridge you can fetch the tor software.
  - more strategies for distributing bridge addresses in a way that
    doesn't rely on knowing somebody who runs a bridge for you.
  - A way to adjust router status flags from the controller.  (How do we
    prevent the authority from clobbering them soon afterward?)
  - Bridge authorities should do reachability testing but only on the
    purpose==bridge descriptors they have.
  - Clients should estimate their skew as median of skew from servers
    over last N seconds.
  - Start on the WSAENOBUFS solution.
  - Stuff that weasel wants:
    - Make Tor able to chroot itself
      o allow it to load an entire config file from control interface
      - document LOADCONF
      - log rotation (and FD passing) via control interface
      - chroot yourself, including inhibit trying to read config file
        and reopen logs, unless they are under datadir.

Deferred from 0.2.0.x:
  - Proposals
    o 101: Voting on the Tor Directory System (plus 103)
N     - Use if-modified-since on consensus download
      - Controller support
        D GETINFO to get consensus
N       - Event when new consensus arrives
    - 113: Simplifying directory authority administration
    - 110: prevent infinite-length circuits (phase one)
    - 118: Listen on and advertise multiple ports:
      - Tor should be able to have a pool of outgoing IP addresses that it is
        able to rotate through. (maybe.  Possible overlap with proposal 118.)
      - config option to publish what ports you listen on, beyond
        ORPort/DirPort.  It should support ranges and bit prefixes (?) too.
        (This is very similar to proposal 118.)
    - 117: IPv6 Exits
      - Internal code support for ipv6:
        o Clone ipv6 functions (inet_ntop, inet_pton) where they don't exist.
        - Most address variables need to become tor_addr_t
        - Teach resolving code how to handle ipv6.
        - Teach exit policies about ipv6 (consider ipv4/ipv6 interaction!)
  - Features
    - Let controller set router flags for authority to transmit, and for
      client to use.
    - add an 'exit-address' line in the descriptor for servers that exit
      from something that isn't their published address.
    - More work on AvoidDiskWrites?
  - Features
    - Make a TCP DNSPort
  - Protocol work
    - MAYBE kill stalled circuits rather than stalled connections.  This is
      possible thanks to cell queues, but we need to consider the anonymity
      implications.
    - Implement TLS shutdown properly when possible.
  - Bugs
    - If the client's clock is too far in the past, it will drop (or just not
      try to get) descriptors, so it'll never build circuits.
  - Refactoring
    - Make resolves no longer use edge_connection_t unless they are actually
      _on_ a socks connection: have edge_connection_t and (say)
      dns_request_t both extend an edge_stream_t, and have p_streams and
      n_streams both be linked lists of edge_stream_t.
    - Generate torrc.{complete|sample}.in, tor.1.in, the HTML manual, and the
      online config documentation from a single source.
    - Move all status info out of routerinfo into local_routerstatus.  Make
      "who can change what" in local_routerstatus explicit.  Make
      local_routerstatus (or equivalent) subsume all places to go for "what
      router is this?"
  - Blocking/scanning-resistance
    - It would be potentially helpful to respond to https requests on
      the OR port by acting like an HTTPS server.
    - Do we want to maintain our own set of entryguards that we use as
      next hop after the bridge? Open research question; let's say no
      for 0.2.0 unless we learn otherwise.
    - Some mechanism for specifying that we want to stop using a cached
      bridge.
  - Build:
    - Detect correct version of libraries from autoconf script.

=======================================================================

Future versions:
  - deprecate router_digest_is_trusted_dir() in favor of
    router_get_trusteddirserver_by_digest()

  - See also Flyspray tasks.
  - See also all OPEN/ACCEPTED proposals.
  - See also all items marked XXXX and FFFF in the code.

  - Protocol:
    - Our current approach to block attempts to use Tor as a single-hop proxy
      is pretty lame; we should get a better one.
    - Allow small cells and large cells on the same network?
    - Cell buffering and resending. This will allow us to handle broken
      circuits as long as the endpoints don't break, plus will allow
      connection (tls session key) rotation.
    - Implement Morphmix, so we can compare its behavior, complexity,
      etc.  But see paper breaking morphmix.
    - Other transport. HTTP, udp, rdp, airhook, etc. May have to do our own
      link crypto, unless we can bully DTLS into it.
    - Need a relay teardown cell, separate from one-way ends.
      (Pending a user who needs this)
    - Handle half-open connections: right now we don't support all TCP
      streams, at least according to the protocol. But we handle all that
      we've seen in the wild.
      (Pending a user who needs this)

  - Directory system
    - BEGIN_DIR items
      X turn the received socks addr:port into a digest for setting .exit
      - handle connect-dir streams that don't have a chosen_exit_name set.
    - Have a "Faster" status flag that means it. Fast2, Fast4, Fast8?
    - Add an option (related to AvoidDiskWrites) to disable directory
      caching.  (Is this actually a good idea??)
    - Add d64 and fp64 along-side d and fp so people can paste status
      entries into a url. since + is a valid base64 char, only allow one
      at a time. Consider adding to controller as well.
    - Some back-out mechanism for auto-approval on authorities
      - a way of rolling back approvals to before a timestamp
        - Consider minion-like fingerprint file/log combination.
    - Have new people be in limbo and need to demonstrate usefulness
      before we approve them.

  - Hidden services:
    - Standby/hotswap/redundant hidden services.
    . Update the hidden service stuff for the new dir approach.  (Much
      of this will be superseded by 114.)
      - switch to an ascii format, maybe sexpr?
      - authdirservers publish blobs of them.
      - other authdirservers fetch these blobs.
      - hidserv people have the option of not uploading their blobs.
      - you can insert a blob via the controller.
      - and there's some amount of backwards compatibility.
      - teach clients, intro points, and hidservs about auth mechanisms.
      - come up with a few more auth mechanisms.
    - auth mechanisms to let hidden service midpoint and responder filter
      connection requests.
    - Let each hidden service (or other thing) specify its own
      OutboundBindAddress?
    - Hidserv offerers shouldn't need to define a SocksPort

  - Server operation
    X When we notice a 'Rejected: There is already a named server with
      this nickname' message... or maybe instead when we see in the
      networkstatuses that somebody else is Named with the name we
      want: warn the user, send a STATUS_SERVER message, and fall back
      to unnamed.
    - If the server is spewing complaints about raising your ulimit -n,
      we should add a note about this to the server descriptor so other
      people can notice too.
    - When we hit a funny error from a dir request (eg 403 forbidden),
      but tor is working and happy otherwise, and we haven't seen many
      such errors recently, then don't warn about it.

  - Controller
    - Implement missing status events and accompanying getinfos
      - DIR_REACHABLE
      - BAD_DIR_RESPONSE (Unexpected directory response; maybe we're behind
        a firewall.)
      - BAD_PROXY (Bad http or https proxy)
      - UNRECOGNIZED_ROUTER (a nickname we asked for is unavailable)
      - Status events related to hibernation
      - something about failing to parse our address?
        from resolve_my_address() in config.c
      - sketchy OS, sketchy threading
      - too many onions queued: threading problems or slow CPU?
    - Implement missing status event fields:
      - TIMEOUT on CHECKING_REACHABILITY
    - GETINFO status/client, status/server, status/general: There should be
      some way to learn which status events are currently "in effect."
      We should specify which these are, what format they appear in, and so
      on.
    - More information in events:
      - Include bandwidth breakdown by conn->type in BW events.
      - Change circuit status events to give more details, like purpose,
        whether they're internal, when they become dirty, when they become
        too dirty for further circuits, etc.
      - Change stream status events analogously.
    - Expose more information via getinfo:
      - import and export rendezvous descriptors
      - Review all static fields for additional candidates
    - Allow EXTENDCIRCUIT to unknown server.
      - We need some way to adjust server status, and to tell tor not to
        download directories/network-status, and a way to force a download.
      - Make everything work with hidden services

  - Performance/resources
    - per-conn write buckets
    - separate config options for read vs write limiting
      (It's hard to support read > write, since we need better
       congestion control to avoid overfull buffers there.  So,
       defer the whole thing.)
    - Look into pulling serverdescs off buffers as they arrive.
    - Rate limit exit connections to a given destination -- this helps
      us play nice with websites when Tor users want to crawl them; it
      also introduces DoS opportunities.
    - Consider truncating rather than destroying failed circuits,
      in order to save the effort of restarting.  There are security
      issues here that need thinking, though.
    - Handle full buffers without totally borking
    - Rate-limit OR and directory connections overall and per-IP and
      maybe per subnet.

  - Misc
    - Hold-open-until-flushed now works by accident; it should work by
      design.
    - Display the reasons in 'destroy' and 'truncated' cells under
      some circumstances?
    - Make router_is_general_exit() a bit smarter once we're sure what
      it's for.
    - Automatically determine what ports are reachable and start using
      those, if circuits aren't working and it's a pattern we
      recognize ("port 443 worked once and port 9001 keeps not
      working").

  - Security
    - some better fix for bug #516?
    - don't do dns hijacking tests if we're reject *:* exit policy?
      (deferred until 0.1.1.x is less common)
    - Directory guards
    - Mini-SoaT:
      - Servers might check certs for known-good ssl websites, and if
        they come back self-signed, declare themselves to be
        non-exits.  Similar to how we test for broken/evil dns now.
      - Authorities should try using exits for http to connect to some
        URLS (specified in a configuration file, so as not to make the
        List Of Things Not To Censor completely obvious) and ask them
        for results.  Exits that don't give good answers should have
        the BadExit flag set.
      - Alternatively, authorities should be able to import opinions
        from Snakes on a Tor.
    - More consistent error checking in router_parse_entry_from_string().
      I can say "banana" as my bandwidthcapacity, and it won't even squeak.
    - Bind to random port when making outgoing connections to Tor servers,
      to reduce remote sniping attacks.
    - Audit everything to make sure rend and intro points are just as
      likely to be us as not.
    - Do something to prevent spurious EXTEND cells from making
      middleman nodes connect all over.  Rate-limit failed
      connections, perhaps?
    - DoS protection: TLS puzzles, public key ops, bandwidth exhaustion.

  - Needs thinking
    - Now that we're avoiding exits when picking non-exit positions,
      we need to consider how to pick nodes for internal circuits. If
      we avoid exits for all positions, we skew the load balancing. If
      we accept exits for all positions, we leak whether it's an
      internal circuit at every step. If we accept exits only at the
      last hop, we reintroduce Lasse's attacks from the Oakland paper.

  - Windows server usability
    - Solve the ENOBUFS problem.
      - make tor's use of openssl operate on buffers rather than sockets,
        so we can make use of libevent's buffer paradigm once it has one.
      - make tor's use of libevent tolerate either the socket or the
        buffer paradigm; includes unifying the functions in connect.c.
    - We need a getrlimit equivalent on Windows so we can reserve some
      file descriptors for saving files, etc. Otherwise we'll trigger
      asserts when we're out of file descriptors and crash.
    - Merge code from Urz into libevent
    - Make Tor use evbuffers.

  - Documentation
    - a way to generate the website diagrams from source, so we can
      translate them as utf-8 text rather than with gimp. (svg? or
      imagemagick?)
    . Flesh out options_description array in src/or/config.c
    . multiple sample torrc files
    . figure out how to make nt service stuff work?
      . Document it.
    - Refactor tor man page to divide generally useful options from
      less useful ones?
    - Add a doxygen style checker to make check-spaces so nick doesn't drift
       too far from arma's undocumented styleguide.  Also, document that
       styleguide in HACKING.  (See r9634 for example.)
       - exactly one space at beginning and at end of comments, except i
         guess when there's line-length pressure.
       - if we refer to a function name, put a () after it.
       - only write <b>foo</b> when foo is an argument to this function.
       - doxygen comments must always end in some form of punctuation.
       - capitalize the first sentence in the doxygen comment, except
         when you shouldn't.
       - avoid spelling errors and incorrect comments. ;)

  - Packaging
    - The Debian package now uses --verify-config when (re)starting,
      to distinguish configuration errors from other errors. Perhaps
      the RPM and other startup scripts should too?
    - add a "default.action" file to the tor/vidalia bundle so we can
      fix the https thing in the default configuration:
      http://wiki.noreply.org/noreply/TheOnionRouter/TorFAQ#PrivoxyWeirdSSLPort

  - Related tools
    X Patch privoxy and socks protocol to pass strings to the browser.

=======================================================================

Documentation, non-version-specific.
  - Specs
    - Mark up spec; note unclear points about servers
NR  - write a spec appendix for 'being nice with tor'
    - Specify the keys and key rotation schedules and stuff
  - Mention controller libs someplace.
  - Remove need for HACKING file.
  - document http://wiki.noreply.org/noreply/TheOnionRouter/TransparentProxy on freebsd and osx
P - figure out why x86_64 won't build rpms from tor.spec
P - figure out rpm spec files for bundles of vidalia-tor-polipo
P - figure out polipo install scripts for bundles of vidalia-tor-polipo on osx, win32
  - figure out selinux policy for tor
P - change packaging system to more automated and specific for each
     platform, suggested by Paul Wouter
P - Setup repos for redhat and suse rpms & start signing the rpms the
    way package management apps prefer

Website:
J . tor-in-the-media page
P  - Figure out licenses for website material.
    (Phobos reccomends the Open Publication License with Option A at
    http://opencontent.org/openpub/)
P  - put the logo on the website, in source form, so people can put it on
    stickers directly, etc.
P  - put the source image for the stickers on the website, so people can
    print their own
P - figure out a license for the logos and docs we publish (trademark
figures into this)
    (Phobos reccomends the Open Publication License with Option A at
    http://opencontent.org/openpub/)
P  - ask Jan/Jens to be the translation coordinator? add to volunteer page.
I - add a page for localizing all tor's components.
  - It would be neat if we had a single place that described _all_ the
    tor-related tools you can use, and what they give you, and how well they
    work.  Right now, we don't give a lot of guidance wrt
    torbutton/foxproxy/privoxy/polipo in any consistent place.
P - create a 'blog badge' for tor fans to link to and feature on their
    blogs. A sample can be found at http://interloper.org/tmp/tor/tor-button.png

  - Tor mirrors
    - make a mailing list with the mirror operators
    - make an automated tool to check /project/trace/ at mirrors to
      learn which ones are lagging behind.
    - auto (or manually) cull the mirrors that are broken; and
      contact their operator?
    - a set of instructions for mirror operators to make their apaches
      serve our charsets correctly, and bonus points for language
      negotiation.
    - figure out how to load-balance the downloads across mirrors?
    - ponder how to get users to learn that they should google for
      "tor mirrors" if the main site is blocked.
    - find a mirror volunteer to coordinate all of this