/* Copyright (c) 2001 Matej Pfajfar.
* Copyright (c) 2001-2004, Roger Dingledine.
* Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
* Copyright (c) 2007-2017, The Tor Project, Inc. */
/* See LICENSE for licensing information */
/**
* \file networkstatus.c
* \brief Functions and structures for handling networkstatus documents as a
* client or as a directory cache.
*
* A consensus networkstatus object is created by the directory
* authorities. It authenticates a set of network parameters--most
* importantly, the list of all the relays in the network. This list
* of relays is represented as an array of routerstatus_t objects.
*
* There are currently two flavors of consensus. With the older "NS"
* flavor, each relay is associated with a digest of its router
* descriptor. Tor instances that use this consensus keep the list of
* router descriptors as routerinfo_t objects stored and managed in
* routerlist.c. With the newer "microdesc" flavor, each relay is
* associated with a digest of the microdescriptor that the authorities
* made for it. These are stored and managed in microdesc.c. Information
* about the router is divided between the the networkstatus and the
* microdescriptor according to the general rule that microdescriptors
* should hold information that changes much less frequently than the
* information in the networkstatus.
*
* Modern clients use microdescriptor networkstatuses. Directory caches
* need to keep both kinds of networkstatus document, so they can serve them.
*
* This module manages fetching, holding, storing, updating, and
* validating networkstatus objects. The download-and-validate process
* is slightly complicated by the fact that the keys you need to
* validate a consensus are stored in the authority certificates, which
* you might not have yet when you download the consensus.
*/
#define NETWORKSTATUS_PRIVATE
#include "or.h"
#include "bridges.h"
#include "channel.h"
#include "circuitmux.h"
#include "circuitmux_ewma.h"
#include "circuitstats.h"
#include "config.h"
#include "connection.h"
#include "connection_or.h"
#include "consdiffmgr.h"
#include "control.h"
#include "directory.h"
#include "dirserv.h"
#include "dirvote.h"
#include "dos.h"
#include "entrynodes.h"
#include "hibernate.h"
#include "main.h"
#include "microdesc.h"
#include "networkstatus.h"
#include "nodelist.h"
#include "protover.h"
#include "relay.h"
#include "router.h"
#include "routerlist.h"
#include "routerparse.h"
#include "scheduler.h"
#include "shared_random.h"
#include "transports.h"
#include "torcert.h"
#include "channelpadding.h"
/** Most recently received and validated v3 "ns"-flavored consensus network
* status. */
STATIC networkstatus_t *current_ns_consensus = NULL;
/** Most recently received and validated v3 "microdesc"-flavored consensus
* network status. */
STATIC networkstatus_t *current_md_consensus = NULL;
/** A v3 consensus networkstatus that we've received, but which we don't
* have enough certificates to be happy about. */
typedef struct consensus_waiting_for_certs_t {
/** The consensus itself. */
networkstatus_t *consensus;
/** The encoded version of the consensus, nul-terminated. */
char *body;
/** When did we set the current value of consensus_waiting_for_certs? If
* this is too recent, we shouldn't try to fetch a new consensus for a
* little while, to give ourselves time to get certificates for this one. */
time_t set_at;
/** Set to 1 if we've been holding on to it for so long we should maybe
* treat it as being bad. */
int dl_failed;
} consensus_waiting_for_certs_t;
/** An array, for each flavor of consensus we might want, of consensuses that
* we have downloaded, but which we cannot verify due to having insufficient
* authority certificates. */
static consensus_waiting_for_certs_t
consensus_waiting_for_certs[N_CONSENSUS_FLAVORS];
/** A time before which we shouldn't try to replace the current consensus:
* this will be at some point after the next consensus becomes valid, but
* before the current consensus becomes invalid. */
static time_t time_to_download_next_consensus[N_CONSENSUS_FLAVORS];
/** Download status for the current consensus networkstatus. */
static download_status_t consensus_dl_status[N_CONSENSUS_FLAVORS] =
{
{ 0, 0, 0, DL_SCHED_CONSENSUS, DL_WANT_ANY_DIRSERVER,
DL_SCHED_INCREMENT_FAILURE, DL_SCHED_RANDOM_EXPONENTIAL, 0, 0 },
{ 0, 0, 0, DL_SCHED_CONSENSUS, DL_WANT_ANY_DIRSERVER,
DL_SCHED_INCREMENT_FAILURE, DL_SCHED_RANDOM_EXPONENTIAL, 0, 0 },
};
#define N_CONSENSUS_BOOTSTRAP_SCHEDULES 2
#define CONSENSUS_BOOTSTRAP_SOURCE_AUTHORITY 0
#define CONSENSUS_BOOTSTRAP_SOURCE_ANY_DIRSERVER 1
/* Using DL_SCHED_INCREMENT_ATTEMPT on these schedules means that
* download_status_increment_failure won't increment these entries.
* However, any bootstrap connection failures that occur after we have
* a valid consensus will count against the failure counts on the non-bootstrap
* schedules. There should only be one of these, as all the others will have
* been cancelled. (This doesn't seem to be a significant issue.) */
static download_status_t
consensus_bootstrap_dl_status[N_CONSENSUS_BOOTSTRAP_SCHEDULES] =
{
{ 0, 0, 0, DL_SCHED_CONSENSUS, DL_WANT_AUTHORITY,
DL_SCHED_INCREMENT_ATTEMPT, DL_SCHED_RANDOM_EXPONENTIAL, 0, 0 },
/* During bootstrap, DL_WANT_ANY_DIRSERVER means "use fallbacks". */
{ 0, 0, 0, DL_SCHED_CONSENSUS, DL_WANT_ANY_DIRSERVER,
DL_SCHED_INCREMENT_ATTEMPT, DL_SCHED_RANDOM_EXPONENTIAL, 0, 0 },
};
/** True iff we have logged a warning about this OR's version being older than
* listed by the authorities. */
static int have_warned_about_old_version = 0;
/** True iff we have logged a warning about this OR's version being newer than
* listed by the authorities. */
static int have_warned_about_new_version = 0;
static void update_consensus_bootstrap_multiple_downloads(
time_t now,
const or_options_t *options);
static int networkstatus_check_required_protocols(const networkstatus_t *ns,
int client_mode,
char **warning_out);
/** Forget that we've warned about anything networkstatus-related, so we will
* give fresh warnings if the same behavior happens again. */
void
networkstatus_reset_warnings(void)
{
SMARTLIST_FOREACH(nodelist_get_list(), node_t *, node,
node->name_lookup_warned = 0);
have_warned_about_old_version = 0;
have_warned_about_new_version = 0;
}
/** Reset the descriptor download failure count on all networkstatus docs, so
* that we can retry any long-failed documents immediately.
*/
void
networkstatus_reset_download_failures(void)
{
int i;
log_debug(LD_GENERAL,
"In networkstatus_reset_download_failures()");
for (i=0; i < N_CONSENSUS_FLAVORS; ++i)
download_status_reset(&consensus_dl_status[i]);
for (i=0; i < N_CONSENSUS_BOOTSTRAP_SCHEDULES; ++i)
download_status_reset(&consensus_bootstrap_dl_status[i]);
}
/**
* Read and and return the cached consensus of type flavorname. If
* unverified is false, get the one we haven't verified. Return NULL if
* the file isn't there. */
static char *
networkstatus_read_cached_consensus_impl(int flav,
const char *flavorname,
int unverified_consensus)
{
char buf[128];
const char *prefix;
if (unverified_consensus) {
prefix = "unverified";
} else {
prefix = "cached";
}
if (flav == FLAV_NS) {
tor_snprintf(buf, sizeof(buf), "%s-consensus", prefix);
} else {
tor_snprintf(buf, sizeof(buf), "%s-%s-consensus", prefix, flavorname);
}
char *filename = get_cachedir_fname(buf);
char *result = read_file_to_str(filename, RFTS_IGNORE_MISSING, NULL);
tor_free(filename);
return result;
}
/** Return a new string containing the current cached consensus of flavor
* flavorname. */
char *
networkstatus_read_cached_consensus(const char *flavorname)
{
int flav = networkstatus_parse_flavor_name(flavorname);
if (flav < 0)
return NULL;
return networkstatus_read_cached_consensus_impl(flav, flavorname, 0);
}
/** Read every cached v3 consensus networkstatus from the disk. */
int
router_reload_consensus_networkstatus(void)
{
const unsigned int flags = NSSET_FROM_CACHE | NSSET_DONT_DOWNLOAD_CERTS;
int flav;
/* FFFF Suppress warnings if cached consensus is bad? */
for (flav = 0; flav < N_CONSENSUS_FLAVORS; ++flav) {
const char *flavor = networkstatus_get_flavor_name(flav);
char *s = networkstatus_read_cached_consensus_impl(flav, flavor, 0);
if (s) {
if (networkstatus_set_current_consensus(s, flavor, flags, NULL) < -1) {
log_warn(LD_FS, "Couldn't load consensus %s networkstatus from cache",
flavor);
}
tor_free(s);
}
s = networkstatus_read_cached_consensus_impl(flav, flavor, 1);
if (s) {
if (networkstatus_set_current_consensus(s, flavor,
flags|NSSET_WAS_WAITING_FOR_CERTS,
NULL)) {
log_info(LD_FS, "Couldn't load unverified consensus %s networkstatus "
"from cache", flavor);
}
tor_free(s);
}
}
update_certificate_downloads(time(NULL));
routers_update_all_from_networkstatus(time(NULL), 3);
update_microdescs_from_networkstatus(time(NULL));
return 0;
}
/** Free all storage held by the vote_routerstatus object rs. */
void
vote_routerstatus_free_(vote_routerstatus_t *rs)
{
vote_microdesc_hash_t *h, *next;
if (!rs)
return;
tor_free(rs->version);
tor_free(rs->protocols);
tor_free(rs->status.exitsummary);
for (h = rs->microdesc; h; h = next) {
tor_free(h->microdesc_hash_line);
next = h->next;
tor_free(h);
}
tor_free(rs);
}
/** Free all storage held by the routerstatus object rs. */
void
routerstatus_free_(routerstatus_t *rs)
{
if (!rs)
return;
tor_free(rs->exitsummary);
tor_free(rs);
}
/** Free all storage held in sig */
void
document_signature_free_(document_signature_t *sig)
{
tor_free(sig->signature);
tor_free(sig);
}
/** Return a newly allocated copy of sig */
document_signature_t *
document_signature_dup(const document_signature_t *sig)
{
document_signature_t *r = tor_memdup(sig, sizeof(document_signature_t));
if (r->signature)
r->signature = tor_memdup(sig->signature, sig->signature_len);
return r;
}
/** Free all storage held in ns. */
void
networkstatus_vote_free_(networkstatus_t *ns)
{
if (!ns)
return;
tor_free(ns->client_versions);
tor_free(ns->server_versions);
tor_free(ns->recommended_client_protocols);
tor_free(ns->recommended_relay_protocols);
tor_free(ns->required_client_protocols);
tor_free(ns->required_relay_protocols);
if (ns->known_flags) {
SMARTLIST_FOREACH(ns->known_flags, char *, c, tor_free(c));
smartlist_free(ns->known_flags);
}
if (ns->weight_params) {
SMARTLIST_FOREACH(ns->weight_params, char *, c, tor_free(c));
smartlist_free(ns->weight_params);
}
if (ns->net_params) {
SMARTLIST_FOREACH(ns->net_params, char *, c, tor_free(c));
smartlist_free(ns->net_params);
}
if (ns->supported_methods) {
SMARTLIST_FOREACH(ns->supported_methods, char *, c, tor_free(c));
smartlist_free(ns->supported_methods);
}
if (ns->package_lines) {
SMARTLIST_FOREACH(ns->package_lines, char *, c, tor_free(c));
smartlist_free(ns->package_lines);
}
if (ns->voters) {
SMARTLIST_FOREACH_BEGIN(ns->voters, networkstatus_voter_info_t *, voter) {
tor_free(voter->nickname);
tor_free(voter->address);
tor_free(voter->contact);
if (voter->sigs) {
SMARTLIST_FOREACH(voter->sigs, document_signature_t *, sig,
document_signature_free(sig));
smartlist_free(voter->sigs);
}
tor_free(voter);
} SMARTLIST_FOREACH_END(voter);
smartlist_free(ns->voters);
}
authority_cert_free(ns->cert);
if (ns->routerstatus_list) {
if (ns->type == NS_TYPE_VOTE || ns->type == NS_TYPE_OPINION) {
SMARTLIST_FOREACH(ns->routerstatus_list, vote_routerstatus_t *, rs,
vote_routerstatus_free(rs));
} else {
SMARTLIST_FOREACH(ns->routerstatus_list, routerstatus_t *, rs,
routerstatus_free(rs));
}
smartlist_free(ns->routerstatus_list);
}
digestmap_free(ns->desc_digest_map, NULL);
if (ns->sr_info.commits) {
SMARTLIST_FOREACH(ns->sr_info.commits, sr_commit_t *, c,
sr_commit_free(c));
smartlist_free(ns->sr_info.commits);
}
tor_free(ns->sr_info.previous_srv);
tor_free(ns->sr_info.current_srv);
memwipe(ns, 11, sizeof(*ns));
tor_free(ns);
}
/** Return the voter info from vote for the voter whose identity digest
* is identity, or NULL if no such voter is associated with
* vote. */
networkstatus_voter_info_t *
networkstatus_get_voter_by_id(networkstatus_t *vote,
const char *identity)
{
if (!vote || !vote->voters)
return NULL;
SMARTLIST_FOREACH(vote->voters, networkstatus_voter_info_t *, voter,
if (fast_memeq(voter->identity_digest, identity, DIGEST_LEN))
return voter);
return NULL;
}
/** Check whether the signature sig is correctly signed with the
* signing key in cert. Return -1 if cert doesn't match the
* signing key; otherwise set the good_signature or bad_signature flag on
* voter, and return 0. */
int
networkstatus_check_document_signature(const networkstatus_t *consensus,
document_signature_t *sig,
const authority_cert_t *cert)
{
char key_digest[DIGEST_LEN];
const int dlen = sig->alg == DIGEST_SHA1 ? DIGEST_LEN : DIGEST256_LEN;
char *signed_digest;
size_t signed_digest_len;
if (crypto_pk_get_digest(cert->signing_key, key_digest)<0)
return -1;
if (tor_memneq(sig->signing_key_digest, key_digest, DIGEST_LEN) ||
tor_memneq(sig->identity_digest, cert->cache_info.identity_digest,
DIGEST_LEN))
return -1;
if (authority_cert_is_blacklisted(cert)) {
/* We implement blacklisting for authority signing keys by treating
* all their signatures as always bad. That way we don't get into
* crazy loops of dropping and re-fetching signatures. */
log_warn(LD_DIR, "Ignoring a consensus signature made with deprecated"
" signing key %s",
hex_str(cert->signing_key_digest, DIGEST_LEN));
sig->bad_signature = 1;
return 0;
}
signed_digest_len = crypto_pk_keysize(cert->signing_key);
signed_digest = tor_malloc(signed_digest_len);
if (crypto_pk_public_checksig(cert->signing_key,
signed_digest,
signed_digest_len,
sig->signature,
sig->signature_len) < dlen ||
tor_memneq(signed_digest, consensus->digests.d[sig->alg], dlen)) {
log_warn(LD_DIR, "Got a bad signature on a networkstatus vote");
sig->bad_signature = 1;
} else {
sig->good_signature = 1;
}
tor_free(signed_digest);
return 0;
}
/** Given a v3 networkstatus consensus in consensus, check every
* as-yet-unchecked signature on consensus. Return 1 if there is a
* signature from every recognized authority on it, 0 if there are
* enough good signatures from recognized authorities on it, -1 if we might
* get enough good signatures by fetching missing certificates, and -2
* otherwise. Log messages at INFO or WARN: if warn is over 1, warn
* about every problem; if warn is at least 1, warn only if we can't get
* enough signatures; if warn is negative, log nothing at all. */
int
networkstatus_check_consensus_signature(networkstatus_t *consensus,
int warn)
{
int n_good = 0;
int n_missing_key = 0, n_dl_failed_key = 0;
int n_bad = 0;
int n_unknown = 0;
int n_no_signature = 0;
int n_v3_authorities = get_n_authorities(V3_DIRINFO);
int n_required = n_v3_authorities/2 + 1;
smartlist_t *list_good = smartlist_new();
smartlist_t *list_no_signature = smartlist_new();
smartlist_t *need_certs_from = smartlist_new();
smartlist_t *unrecognized = smartlist_new();
smartlist_t *missing_authorities = smartlist_new();
int severity;
time_t now = time(NULL);
tor_assert(consensus->type == NS_TYPE_CONSENSUS);
SMARTLIST_FOREACH_BEGIN(consensus->voters, networkstatus_voter_info_t *,
voter) {
int good_here = 0;
int bad_here = 0;
int unknown_here = 0;
int missing_key_here = 0, dl_failed_key_here = 0;
SMARTLIST_FOREACH_BEGIN(voter->sigs, document_signature_t *, sig) {
if (!sig->good_signature && !sig->bad_signature &&
sig->signature) {
/* we can try to check the signature. */
int is_v3_auth = trusteddirserver_get_by_v3_auth_digest(
sig->identity_digest) != NULL;
authority_cert_t *cert =
authority_cert_get_by_digests(sig->identity_digest,
sig->signing_key_digest);
tor_assert(tor_memeq(sig->identity_digest, voter->identity_digest,
DIGEST_LEN));
if (!is_v3_auth) {
smartlist_add(unrecognized, voter);
++unknown_here;
continue;
} else if (!cert || cert->expires < now) {
smartlist_add(need_certs_from, voter);
++missing_key_here;
if (authority_cert_dl_looks_uncertain(sig->identity_digest))
++dl_failed_key_here;
continue;
}
if (networkstatus_check_document_signature(consensus, sig, cert) < 0) {
smartlist_add(need_certs_from, voter);
++missing_key_here;
if (authority_cert_dl_looks_uncertain(sig->identity_digest))
++dl_failed_key_here;
continue;
}
}
if (sig->good_signature)
++good_here;
else if (sig->bad_signature)
++bad_here;
} SMARTLIST_FOREACH_END(sig);
if (good_here) {
++n_good;
smartlist_add(list_good, voter->nickname);
} else if (bad_here) {
++n_bad;
} else if (missing_key_here) {
++n_missing_key;
if (dl_failed_key_here)
++n_dl_failed_key;
} else if (unknown_here) {
++n_unknown;
} else {
++n_no_signature;
smartlist_add(list_no_signature, voter->nickname);
}
} SMARTLIST_FOREACH_END(voter);
/* Now see whether we're missing any voters entirely. */
SMARTLIST_FOREACH(router_get_trusted_dir_servers(),
dir_server_t *, ds,
{
if ((ds->type & V3_DIRINFO) &&
!networkstatus_get_voter_by_id(consensus, ds->v3_identity_digest))
smartlist_add(missing_authorities, ds);
});
if (warn > 1 || (warn >= 0 &&
(n_good + n_missing_key - n_dl_failed_key < n_required))) {
severity = LOG_WARN;
} else {
severity = LOG_INFO;
}
if (warn >= 0) {
SMARTLIST_FOREACH(unrecognized, networkstatus_voter_info_t *, voter,
{
tor_log(severity, LD_DIR, "Consensus includes unrecognized authority "
"'%s' at %s:%d (contact %s; identity %s)",
voter->nickname, voter->address, (int)voter->dir_port,
voter->contact?voter->contact:"n/a",
hex_str(voter->identity_digest, DIGEST_LEN));
});
SMARTLIST_FOREACH(need_certs_from, networkstatus_voter_info_t *, voter,
{
tor_log(severity, LD_DIR, "Looks like we need to download a new "
"certificate from authority '%s' at %s:%d (contact %s; "
"identity %s)",
voter->nickname, voter->address, (int)voter->dir_port,
voter->contact?voter->contact:"n/a",
hex_str(voter->identity_digest, DIGEST_LEN));
});
SMARTLIST_FOREACH(missing_authorities, dir_server_t *, ds,
{
tor_log(severity, LD_DIR, "Consensus does not include configured "
"authority '%s' at %s:%d (identity %s)",
ds->nickname, ds->address, (int)ds->dir_port,
hex_str(ds->v3_identity_digest, DIGEST_LEN));
});
{
char *joined;
smartlist_t *sl = smartlist_new();
char *tmp = smartlist_join_strings(list_good, " ", 0, NULL);
smartlist_add_asprintf(sl,
"A consensus needs %d good signatures from recognized "
"authorities for us to accept it. This one has %d (%s).",
n_required, n_good, tmp);
tor_free(tmp);
if (n_no_signature) {
tmp = smartlist_join_strings(list_no_signature, " ", 0, NULL);
smartlist_add_asprintf(sl,
"%d (%s) of the authorities we know didn't sign it.",
n_no_signature, tmp);
tor_free(tmp);
}
if (n_unknown) {
smartlist_add_asprintf(sl,
"It has %d signatures from authorities we don't "
"recognize.", n_unknown);
}
if (n_bad) {
smartlist_add_asprintf(sl, "%d of the signatures on it didn't verify "
"correctly.", n_bad);
}
if (n_missing_key) {
smartlist_add_asprintf(sl,
"We were unable to check %d of the signatures, "
"because we were missing the keys.", n_missing_key);
}
joined = smartlist_join_strings(sl, " ", 0, NULL);
tor_log(severity, LD_DIR, "%s", joined);
tor_free(joined);
SMARTLIST_FOREACH(sl, char *, c, tor_free(c));
smartlist_free(sl);
}
}
smartlist_free(list_good);
smartlist_free(list_no_signature);
smartlist_free(unrecognized);
smartlist_free(need_certs_from);
smartlist_free(missing_authorities);
if (n_good == n_v3_authorities)
return 1;
else if (n_good >= n_required)
return 0;
else if (n_good + n_missing_key >= n_required)
return -1;
else
return -2;
}
/** How far in the future do we allow a network-status to get before removing
* it? (seconds) */
#define NETWORKSTATUS_ALLOW_SKEW (24*60*60)
/** Helper for bsearching a list of routerstatus_t pointers: compare a
* digest in the key to the identity digest of a routerstatus_t. */
int
compare_digest_to_routerstatus_entry(const void *_key, const void **_member)
{
const char *key = _key;
const routerstatus_t *rs = *_member;
return tor_memcmp(key, rs->identity_digest, DIGEST_LEN);
}
/** Helper for bsearching a list of routerstatus_t pointers: compare a
* digest in the key to the identity digest of a routerstatus_t. */
int
compare_digest_to_vote_routerstatus_entry(const void *_key,
const void **_member)
{
const char *key = _key;
const vote_routerstatus_t *vrs = *_member;
return tor_memcmp(key, vrs->status.identity_digest, DIGEST_LEN);
}
/** As networkstatus_find_entry, but do not return a const pointer */
routerstatus_t *
networkstatus_vote_find_mutable_entry(networkstatus_t *ns, const char *digest)
{
return smartlist_bsearch(ns->routerstatus_list, digest,
compare_digest_to_routerstatus_entry);
}
/** Return the entry in ns for the identity digest digest, or
* NULL if none was found. */
const routerstatus_t *
networkstatus_vote_find_entry(networkstatus_t *ns, const char *digest)
{
return networkstatus_vote_find_mutable_entry(ns, digest);
}
/*XXXX MOVE make this static once functions are moved into this file. */
/** Search the routerstatuses in ns for one whose identity digest is
* digest. Return value and set *found_out as for
* smartlist_bsearch_idx(). */
int
networkstatus_vote_find_entry_idx(networkstatus_t *ns,
const char *digest, int *found_out)
{
return smartlist_bsearch_idx(ns->routerstatus_list, digest,
compare_digest_to_routerstatus_entry,
found_out);
}
/** As router_get_consensus_status_by_descriptor_digest, but does not return
* a const pointer. */
MOCK_IMPL(routerstatus_t *,
router_get_mutable_consensus_status_by_descriptor_digest,(
networkstatus_t *consensus,
const char *digest))
{
if (!consensus)
consensus = networkstatus_get_latest_consensus();
if (!consensus)
return NULL;
if (!consensus->desc_digest_map) {
digestmap_t *m = consensus->desc_digest_map = digestmap_new();
SMARTLIST_FOREACH(consensus->routerstatus_list,
routerstatus_t *, rs,
{
digestmap_set(m, rs->descriptor_digest, rs);
});
}
return digestmap_get(consensus->desc_digest_map, digest);
}
/** Return the consensus view of the status of the router whose current
* descriptor digest in consensus is digest, or NULL if
* no such router is known. */
const routerstatus_t *
router_get_consensus_status_by_descriptor_digest(networkstatus_t *consensus,
const char *digest)
{
return router_get_mutable_consensus_status_by_descriptor_digest(
consensus, digest);
}
/** Return a smartlist of all router descriptor digests in a consensus */
static smartlist_t *
router_get_descriptor_digests_in_consensus(networkstatus_t *consensus)
{
smartlist_t *result = smartlist_new();
digestmap_iter_t *i;
const char *digest;
void *rs;
char *digest_tmp;
for (i = digestmap_iter_init(consensus->desc_digest_map);
!(digestmap_iter_done(i));
i = digestmap_iter_next(consensus->desc_digest_map, i)) {
digestmap_iter_get(i, &digest, &rs);
digest_tmp = tor_malloc(DIGEST_LEN);
memcpy(digest_tmp, digest, DIGEST_LEN);
smartlist_add(result, digest_tmp);
}
return result;
}
/** Return a smartlist of all router descriptor digests in the current
* consensus */
MOCK_IMPL(smartlist_t *,
router_get_descriptor_digests,(void))
{
smartlist_t *result = NULL;
if (current_ns_consensus) {
result =
router_get_descriptor_digests_in_consensus(current_ns_consensus);
}
return result;
}
/** Given the digest of a router descriptor, return its current download
* status, or NULL if the digest is unrecognized. */
MOCK_IMPL(download_status_t *,
router_get_dl_status_by_descriptor_digest,(const char *d))
{
routerstatus_t *rs;
if (!current_ns_consensus)
return NULL;
if ((rs = router_get_mutable_consensus_status_by_descriptor_digest(
current_ns_consensus, d)))
return &rs->dl_status;
return NULL;
}
/** As router_get_consensus_status_by_id, but do not return a const pointer */
routerstatus_t *
router_get_mutable_consensus_status_by_id(const char *digest)
{
const networkstatus_t *ns = networkstatus_get_latest_consensus();
if (!ns)
return NULL;
smartlist_t *rslist = ns->routerstatus_list;
return smartlist_bsearch(rslist, digest,
compare_digest_to_routerstatus_entry);
}
/** Return the consensus view of the status of the router whose identity
* digest is digest, or NULL if we don't know about any such router. */
const routerstatus_t *
router_get_consensus_status_by_id(const char *digest)
{
return router_get_mutable_consensus_status_by_id(digest);
}
/** How frequently do directory authorities re-download fresh networkstatus
* documents? */
#define AUTHORITY_NS_CACHE_INTERVAL (10*60)
/** How frequently do non-authority directory caches re-download fresh
* networkstatus documents? */
#define NONAUTHORITY_NS_CACHE_INTERVAL (60*60)
/** Return true iff, given the options listed in options, flavor
* is the flavor of a consensus networkstatus that we would like to fetch.
*
* For certificate fetches, use we_want_to_fetch_unknown_auth_certs, and
* for serving fetched documents, use directory_caches_dir_info. */
int
we_want_to_fetch_flavor(const or_options_t *options, int flavor)
{
if (flavor < 0 || flavor > N_CONSENSUS_FLAVORS) {
/* This flavor is crazy; we don't want it */
/*XXXX handle unrecognized flavors later */
return 0;
}
if (authdir_mode_v3(options) || directory_caches_dir_info(options)) {
/* We want to serve all flavors to others, regardless if we would use
* it ourselves. */
return 1;
}
if (options->FetchUselessDescriptors) {
/* In order to get all descriptors, we need to fetch all consensuses. */
return 1;
}
/* Otherwise, we want the flavor only if we want to use it to build
* circuits. */
return flavor == usable_consensus_flavor();
}
/** Return true iff, given the options listed in options, we would like
* to fetch and store unknown authority certificates.
*
* For consensus and descriptor fetches, use we_want_to_fetch_flavor, and
* for serving fetched certificates, use directory_caches_unknown_auth_certs.
*/
int
we_want_to_fetch_unknown_auth_certs(const or_options_t *options)
{
if (authdir_mode_v3(options) ||
directory_caches_unknown_auth_certs((options))) {
/* We want to serve all certs to others, regardless if we would use
* them ourselves. */
return 1;
}
if (options->FetchUselessDescriptors) {
/* Unknown certificates are definitely useless. */
return 1;
}
/* Otherwise, don't fetch unknown certificates. */
return 0;
}
/** How long will we hang onto a possibly live consensus for which we're
* fetching certs before we check whether there is a better one? */
#define DELAY_WHILE_FETCHING_CERTS (20*60)
/** What is the minimum time we need to have waited fetching certs, before we
* increment the consensus download schedule on failure? */
#define MIN_DELAY_FOR_FETCH_CERT_STATUS_FAILURE (1*60)
/* Check if a downloaded consensus flavor should still wait for certificates
* to download now. If we decide not to wait, check if enough time has passed
* to consider the certificate download failure a separate failure. If so,
* fail dls.
* If waiting for certificates to download, return 1. If not, return 0. */
static int
check_consensus_waiting_for_certs(int flavor, time_t now,
download_status_t *dls)
{
consensus_waiting_for_certs_t *waiting;
/* We should always have a known flavor, because we_want_to_fetch_flavor()
* filters out unknown flavors. */
tor_assert(flavor >= 0 && flavor < N_CONSENSUS_FLAVORS);
waiting = &consensus_waiting_for_certs[flavor];
if (waiting->consensus) {
/* XXXX make sure this doesn't delay sane downloads. */
if (waiting->set_at + DELAY_WHILE_FETCHING_CERTS > now &&
waiting->consensus->valid_until > now) {
return 1;
} else {
if (!waiting->dl_failed) {
if (waiting->set_at + MIN_DELAY_FOR_FETCH_CERT_STATUS_FAILURE > now) {
download_status_failed(dls, 0);
}
waiting->dl_failed=1;
}
}
}
return 0;
}
/** If we want to download a fresh consensus, launch a new download as
* appropriate. */
static void
update_consensus_networkstatus_downloads(time_t now)
{
int i;
const or_options_t *options = get_options();
const int we_are_bootstrapping = networkstatus_consensus_is_bootstrapping(
now);
const int use_multi_conn =
networkstatus_consensus_can_use_multiple_directories(options);
if (should_delay_dir_fetches(options, NULL))
return;
for (i=0; i < N_CONSENSUS_FLAVORS; ++i) {
/* XXXX need some way to download unknown flavors if we are caching. */
const char *resource;
networkstatus_t *c;
int max_in_progress_conns = 1;
if (! we_want_to_fetch_flavor(options, i))
continue;
c = networkstatus_get_latest_consensus_by_flavor(i);
if (! (c && c->valid_after <= now && now <= c->valid_until)) {
/* No live consensus? Get one now!*/
time_to_download_next_consensus[i] = now;
}
if (time_to_download_next_consensus[i] > now)
continue; /* Wait until the current consensus is older. */
resource = networkstatus_get_flavor_name(i);
/* Check if we already have enough connections in progress */
if (we_are_bootstrapping && use_multi_conn) {
max_in_progress_conns =
options->ClientBootstrapConsensusMaxInProgressTries;
}
if (connection_dir_count_by_purpose_and_resource(
DIR_PURPOSE_FETCH_CONSENSUS,
resource)
>= max_in_progress_conns) {
continue;
}
/* Check if we want to launch another download for a usable consensus.
* Only used during bootstrap. */
if (we_are_bootstrapping && use_multi_conn
&& i == usable_consensus_flavor()) {
/* Check if we're already downloading a usable consensus */
if (networkstatus_consensus_is_already_downloading(resource))
continue;
/* Make multiple connections for a bootstrap consensus download. */
update_consensus_bootstrap_multiple_downloads(now, options);
} else {
/* Check if we failed downloading a consensus too recently */
int max_dl_tries = options->TestingConsensusMaxDownloadTries;
/* Let's make sure we remembered to update consensus_dl_status */
tor_assert(consensus_dl_status[i].schedule == DL_SCHED_CONSENSUS);
if (!download_status_is_ready(&consensus_dl_status[i],
now,
max_dl_tries)) {
continue;
}
/* Check if we're waiting for certificates to download */
if (check_consensus_waiting_for_certs(i, now, &consensus_dl_status[i]))
continue;
/* Try the requested attempt */
log_info(LD_DIR, "Launching %s standard networkstatus consensus "
"download.", networkstatus_get_flavor_name(i));
directory_get_from_dirserver(DIR_PURPOSE_FETCH_CONSENSUS,
ROUTER_PURPOSE_GENERAL, resource,
PDS_RETRY_IF_NO_SERVERS,
consensus_dl_status[i].want_authority);
}
}
}
/** When we're bootstrapping, launch one or more consensus download
* connections, if schedule indicates connection(s) should be made after now.
* If is_authority, connect to an authority, otherwise, use a fallback
* directory mirror.
*/
static void
update_consensus_bootstrap_attempt_downloads(
time_t now,
const or_options_t *options,
download_status_t *dls,
download_want_authority_t want_authority)
{
int use_fallbacks = networkstatus_consensus_can_use_extra_fallbacks(options);
int max_dl_tries = options->ClientBootstrapConsensusMaxDownloadTries;
if (!use_fallbacks) {
max_dl_tries =
options->ClientBootstrapConsensusAuthorityOnlyMaxDownloadTries;
}
const char *resource = networkstatus_get_flavor_name(
usable_consensus_flavor());
/* Let's make sure we remembered to update schedule */
tor_assert(dls->schedule == DL_SCHED_CONSENSUS);
/* Allow for multiple connections in the same second, if the schedule value
* is 0. */
while (download_status_is_ready(dls, now, max_dl_tries)) {
log_info(LD_DIR, "Launching %s bootstrap %s networkstatus consensus "
"download.", resource, (want_authority == DL_WANT_AUTHORITY
? "authority"
: "mirror"));
directory_get_from_dirserver(DIR_PURPOSE_FETCH_CONSENSUS,
ROUTER_PURPOSE_GENERAL, resource,
PDS_RETRY_IF_NO_SERVERS, want_authority);
/* schedule the next attempt */
download_status_increment_attempt(dls, resource, now);
}
}
/** If we're bootstrapping, check the connection schedules and see if we want
* to make additional, potentially concurrent, consensus download
* connections.
* Only call when bootstrapping, and when we want to make additional
* connections. Only nodes that satisfy
* networkstatus_consensus_can_use_multiple_directories make additional
* connections.
*/
static void
update_consensus_bootstrap_multiple_downloads(time_t now,
const or_options_t *options)
{
const int usable_flavor = usable_consensus_flavor();
/* make sure we can use multiple connections */
if (!networkstatus_consensus_can_use_multiple_directories(options)) {
return;
}
/* Launch concurrent consensus download attempt(s) based on the mirror and
* authority schedules. Try the mirror first - this makes it slightly more
* likely that we'll connect to the fallback first, and then end the
* authority connection attempt. */
/* If a consensus download fails because it's waiting for certificates,
* we'll fail both the authority and fallback schedules. This is better than
* failing only one of the schedules, and having the other continue
* unchecked.
*/
/* If we don't have or can't use extra fallbacks, don't try them. */
if (networkstatus_consensus_can_use_extra_fallbacks(options)) {
download_status_t *dls_f =
&consensus_bootstrap_dl_status[CONSENSUS_BOOTSTRAP_SOURCE_ANY_DIRSERVER];
if (!check_consensus_waiting_for_certs(usable_flavor, now, dls_f)) {
/* During bootstrap, DL_WANT_ANY_DIRSERVER means "use fallbacks". */
update_consensus_bootstrap_attempt_downloads(now, options, dls_f,
DL_WANT_ANY_DIRSERVER);
}
}
/* Now try an authority. */
download_status_t *dls_a =
&consensus_bootstrap_dl_status[CONSENSUS_BOOTSTRAP_SOURCE_AUTHORITY];
if (!check_consensus_waiting_for_certs(usable_flavor, now, dls_a)) {
update_consensus_bootstrap_attempt_downloads(now, options, dls_a,
DL_WANT_AUTHORITY);
}
}
/** Called when an attempt to download a consensus fails: note that the
* failure occurred, and possibly retry. */
void
networkstatus_consensus_download_failed(int status_code, const char *flavname)
{
int flav = networkstatus_parse_flavor_name(flavname);
if (flav >= 0) {
tor_assert(flav < N_CONSENSUS_FLAVORS);
/* XXXX handle unrecognized flavors */
download_status_failed(&consensus_dl_status[flav], status_code);
/* Retry immediately, if appropriate. */
update_consensus_networkstatus_downloads(time(NULL));
}
}
/** How long do we (as a cache) wait after a consensus becomes non-fresh
* before trying to fetch another? */
#define CONSENSUS_MIN_SECONDS_BEFORE_CACHING 120
/** Update the time at which we'll consider replacing the current
* consensus of flavor flav */
static void
update_consensus_networkstatus_fetch_time_impl(time_t now, int flav)
{
const or_options_t *options = get_options();
networkstatus_t *c = networkstatus_get_latest_consensus_by_flavor(flav);
const char *flavor = networkstatus_get_flavor_name(flav);
if (! we_want_to_fetch_flavor(get_options(), flav))
return;
if (c && c->valid_after <= now && now <= c->valid_until) {
long dl_interval;
long interval = c->fresh_until - c->valid_after;
long min_sec_before_caching = CONSENSUS_MIN_SECONDS_BEFORE_CACHING;
time_t start;
if (min_sec_before_caching > interval/16) {
/* Usually we allow 2-minutes slop factor in case clocks get
desynchronized a little. If we're on a private network with
a crazy-fast voting interval, though, 2 minutes may be too
much. */
min_sec_before_caching = interval/16;
/* make sure we always delay by at least a second before caching */
if (min_sec_before_caching == 0) {
min_sec_before_caching = 1;
}
}
if (directory_fetches_dir_info_early(options)) {
/* We want to cache the next one at some point after this one
* is no longer fresh... */
start = (time_t)(c->fresh_until + min_sec_before_caching);
/* Some clients may need the consensus sooner than others. */
if (options->FetchDirInfoExtraEarly || authdir_mode_v3(options)) {
dl_interval = 60;
if (min_sec_before_caching + dl_interval > interval)
dl_interval = interval/2;
} else {
/* But only in the first half-interval after that. */
dl_interval = interval/2;
}
} else {
/* We're an ordinary client, a bridge, or a hidden service.
* Give all the caches enough time to download the consensus. */
start = (time_t)(c->fresh_until + (interval*3)/4);
/* But download the next one well before this one is expired. */
dl_interval = ((c->valid_until - start) * 7 )/ 8;
/* If we're a bridge user, make use of the numbers we just computed
* to choose the rest of the interval *after* them. */
if (directory_fetches_dir_info_later(options)) {
/* Give all the *clients* enough time to download the consensus. */
start = (time_t)(start + dl_interval + min_sec_before_caching);
/* But try to get it before ours actually expires. */
dl_interval = (c->valid_until - start) - min_sec_before_caching;
}
}
/* catch low dl_interval in crazy-fast networks */
if (dl_interval < 1)
dl_interval = 1;
/* catch late start in crazy-fast networks */
if (start+dl_interval >= c->valid_until)
start = c->valid_until - dl_interval - 1;
log_debug(LD_DIR,
"fresh_until: %ld start: %ld "
"dl_interval: %ld valid_until: %ld ",
(long)c->fresh_until, (long)start, dl_interval,
(long)c->valid_until);
/* We must not try to replace c while it's still fresh: */
tor_assert(c->fresh_until < start);
/* We must download the next one before c is invalid: */
tor_assert(start+dl_interval < c->valid_until);
time_to_download_next_consensus[flav] =
start + crypto_rand_int((int)dl_interval);
{
char tbuf1[ISO_TIME_LEN+1];
char tbuf2[ISO_TIME_LEN+1];
char tbuf3[ISO_TIME_LEN+1];
format_local_iso_time(tbuf1, c->fresh_until);
format_local_iso_time(tbuf2, c->valid_until);
format_local_iso_time(tbuf3, time_to_download_next_consensus[flav]);
log_info(LD_DIR, "Live %s consensus %s the most recent until %s and "
"will expire at %s; fetching the next one at %s.",
flavor, (c->fresh_until > now) ? "will be" : "was",
tbuf1, tbuf2, tbuf3);
}
} else {
time_to_download_next_consensus[flav] = now;
log_info(LD_DIR, "No live %s consensus; we should fetch one immediately.",
flavor);
}
}
/** Update the time at which we'll consider replacing the current
* consensus of flavor 'flavor' */
void
update_consensus_networkstatus_fetch_time(time_t now)
{
int i;
for (i = 0; i < N_CONSENSUS_FLAVORS; ++i) {
if (we_want_to_fetch_flavor(get_options(), i))
update_consensus_networkstatus_fetch_time_impl(now, i);
}
}
/** Return 1 if there's a reason we shouldn't try any directory
* fetches yet (e.g. we demand bridges and none are yet known).
* Else return 0.
* If we return 1 and msg_out is provided, set msg_out
* to an explanation of why directory fetches are delayed. (If we
* return 0, we set msg_out to NULL.)
*/
int
should_delay_dir_fetches(const or_options_t *options, const char **msg_out)
{
if (msg_out) {
*msg_out = NULL;
}
if (options->DisableNetwork) {
if (msg_out) {
*msg_out = "DisableNetwork is set.";
}
log_info(LD_DIR, "Delaying dir fetches (DisableNetwork is set)");
return 1;
}
if (we_are_hibernating()) {
if (msg_out) {
*msg_out = "We are hibernating or shutting down.";
}
log_info(LD_DIR, "Delaying dir fetches (Hibernating or shutting down)");
return 1;
}
if (options->UseBridges) {
/* If we know that none of our bridges can possibly work, avoid fetching
* directory documents. But if some of them might work, try again. */
if (num_bridges_usable(1) == 0) {
if (msg_out) {
*msg_out = "No running bridges";
}
log_info(LD_DIR, "Delaying dir fetches (no running bridges known)");
return 1;
}
if (pt_proxies_configuration_pending()) {
if (msg_out) {
*msg_out = "Pluggable transport proxies still configuring";
}
log_info(LD_DIR, "Delaying dir fetches (pt proxies still configuring)");
return 1;
}
}
return 0;
}
/** Launch requests for networkstatus documents and authority certificates as
* appropriate. */
void
update_networkstatus_downloads(time_t now)
{
const or_options_t *options = get_options();
if (should_delay_dir_fetches(options, NULL))
return;
update_consensus_networkstatus_downloads(now);
update_certificate_downloads(now);
}
/** Launch requests as appropriate for missing directory authority
* certificates. */
void
update_certificate_downloads(time_t now)
{
int i;
for (i = 0; i < N_CONSENSUS_FLAVORS; ++i) {
if (consensus_waiting_for_certs[i].consensus)
authority_certs_fetch_missing(consensus_waiting_for_certs[i].consensus,
now, NULL);
}
if (current_ns_consensus)
authority_certs_fetch_missing(current_ns_consensus, now, NULL);
if (current_md_consensus)
authority_certs_fetch_missing(current_md_consensus, now, NULL);
}
/** Return 1 if we have a consensus but we don't have enough certificates
* to start using it yet. */
int
consensus_is_waiting_for_certs(void)
{
return consensus_waiting_for_certs[usable_consensus_flavor()].consensus
? 1 : 0;
}
/** Look up the currently active (depending on bootstrap status) download
* status for this consensus flavor and return a pointer to it.
*/
MOCK_IMPL(download_status_t *,
networkstatus_get_dl_status_by_flavor,(consensus_flavor_t flavor))
{
download_status_t *dl = NULL;
const int we_are_bootstrapping =
networkstatus_consensus_is_bootstrapping(time(NULL));
if ((int)flavor <= N_CONSENSUS_FLAVORS) {
dl = &((we_are_bootstrapping ?
consensus_bootstrap_dl_status : consensus_dl_status)[flavor]);
}
return dl;
}
/** Look up the bootstrap download status for this consensus flavor
* and return a pointer to it. */
MOCK_IMPL(download_status_t *,
networkstatus_get_dl_status_by_flavor_bootstrap,(consensus_flavor_t flavor))
{
download_status_t *dl = NULL;
if ((int)flavor <= N_CONSENSUS_FLAVORS) {
dl = &(consensus_bootstrap_dl_status[flavor]);
}
return dl;
}
/** Look up the running (non-bootstrap) download status for this consensus
* flavor and return a pointer to it. */
MOCK_IMPL(download_status_t *,
networkstatus_get_dl_status_by_flavor_running,(consensus_flavor_t flavor))
{
download_status_t *dl = NULL;
if ((int)flavor <= N_CONSENSUS_FLAVORS) {
dl = &(consensus_dl_status[flavor]);
}
return dl;
}
/** Return the most recent consensus that we have downloaded, or NULL if we
* don't have one. */
MOCK_IMPL(networkstatus_t *,
networkstatus_get_latest_consensus,(void))
{
if (we_use_microdescriptors_for_circuits(get_options()))
return current_md_consensus;
else
return current_ns_consensus;
}
/** Return the latest consensus we have whose flavor matches f, or NULL
* if we don't have one. */
MOCK_IMPL(networkstatus_t *,
networkstatus_get_latest_consensus_by_flavor,(consensus_flavor_t f))
{
if (f == FLAV_NS)
return current_ns_consensus;
else if (f == FLAV_MICRODESC)
return current_md_consensus;
else {
tor_assert(0);
return NULL;
}
}
/** Return the most recent consensus that we have downloaded, or NULL if it is
* no longer live. */
MOCK_IMPL(networkstatus_t *,
networkstatus_get_live_consensus,(time_t now))
{
networkstatus_t *ns = networkstatus_get_latest_consensus();
if (ns && networkstatus_is_live(ns, now))
return ns;
else
return NULL;
}
/** Given a consensus in ns, return true iff currently live and
* unexpired. */
int
networkstatus_is_live(const networkstatus_t *ns, time_t now)
{
return (ns->valid_after <= now && now <= ns->valid_until);
}
/** Determine if consensus is valid or expired recently enough that
* we can still use it.
*
* Return 1 if the consensus is reasonably live, or 0 if it is too old.
*/
int
networkstatus_consensus_reasonably_live(const networkstatus_t *consensus,
time_t now)
{
if (BUG(!consensus))
return 0;
return networkstatus_valid_until_is_reasonably_live(consensus->valid_until,
now);
}
/** As networkstatus_consensus_reasonably_live, but takes a valid_until
* time rather than an entire consensus. */
int
networkstatus_valid_until_is_reasonably_live(time_t valid_until,
time_t now)
{
#define REASONABLY_LIVE_TIME (24*60*60)
return (now <= valid_until + REASONABLY_LIVE_TIME);
}
/* XXXX remove this in favor of get_live_consensus. But actually,
* leave something like it for bridge users, who need to not totally
* lose if they spend a while fetching a new consensus. */
/** As networkstatus_get_live_consensus(), but is way more tolerant of expired
* consensuses. */
networkstatus_t *
networkstatus_get_reasonably_live_consensus(time_t now, int flavor)
{
networkstatus_t *consensus =
networkstatus_get_latest_consensus_by_flavor(flavor);
if (consensus &&
consensus->valid_after <= now &&
networkstatus_consensus_reasonably_live(consensus, now))
return consensus;
else
return NULL;
}
/** Check if we need to download a consensus during tor's bootstrap phase.
* If we have no consensus, or our consensus is unusably old, return 1.
* As soon as we have received a consensus, return 0, even if we don't have
* enough certificates to validate it.
* If a fallback directory gives us a consensus we can never get certs for,
* check_consensus_waiting_for_certs() will wait 20 minutes before failing
* the cert downloads. After that, a new consensus will be fetched from a
* randomly chosen fallback. */
MOCK_IMPL(int,
networkstatus_consensus_is_bootstrapping,(time_t now))
{
/* If we have a validated, reasonably live consensus, we're not
* bootstrapping a consensus at all. */
if (networkstatus_get_reasonably_live_consensus(
now,
usable_consensus_flavor())) {
return 0;
}
/* If we have a consensus, but we're waiting for certificates,
* we're not waiting for a consensus download while bootstrapping. */
if (consensus_is_waiting_for_certs()) {
return 0;
}
/* If we have no consensus, or our consensus is very old, we are
* bootstrapping, and we need to download a consensus. */
return 1;
}
/** Check if we can use multiple directories for a consensus download.
* Only clients (including bridge relays, which act like clients) benefit
* from multiple simultaneous consensus downloads. */
int
networkstatus_consensus_can_use_multiple_directories(
const or_options_t *options)
{
/* If we are a client, bridge, bridge client, or hidden service */
return !public_server_mode(options);
}
/** Check if we can use fallback directory mirrors for a consensus download.
* If we have fallbacks and don't want to fetch from the authorities,
* we can use them. */
MOCK_IMPL(int,
networkstatus_consensus_can_use_extra_fallbacks,(const or_options_t *options))
{
/* The list length comparisons are a quick way to check if we have any
* non-authority fallback directories. If we ever have any authorities that
* aren't fallback directories, we will need to change this code. */
tor_assert(smartlist_len(router_get_fallback_dir_servers())
>= smartlist_len(router_get_trusted_dir_servers()));
/* If we don't fetch from the authorities, and we have additional mirrors,
* we can use them. */
return (!directory_fetches_from_authorities(options)
&& (smartlist_len(router_get_fallback_dir_servers())
> smartlist_len(router_get_trusted_dir_servers())));
}
/* Is there a consensus fetch for flavor resource that's far
* enough along to be attached to a circuit? */
int
networkstatus_consensus_is_already_downloading(const char *resource)
{
int answer = 0;
/* First, get a list of all the dir conns that are fetching a consensus,
* fetching *this* consensus, and are in state "reading" (meaning they
* have already flushed their request onto the socks connection). */
smartlist_t *fetching_conns =
connection_dir_list_by_purpose_resource_and_state(
DIR_PURPOSE_FETCH_CONSENSUS, resource, DIR_CONN_STATE_CLIENT_READING);
/* Then, walk through each conn, to see if its linked socks connection
* is in an attached state. We have to check this separately, since with
* the optimistic data feature, fetches can send their request to the
* socks connection and go into state 'reading', even before they're
* attached to any circuit. */
SMARTLIST_FOREACH_BEGIN(fetching_conns, dir_connection_t *, dirconn) {
/* Do any of these other dir conns have a linked socks conn that is
* attached to a circuit already? */
connection_t *base = TO_CONN(dirconn);
if (base->linked_conn &&
base->linked_conn->type == CONN_TYPE_AP &&
!AP_CONN_STATE_IS_UNATTACHED(base->linked_conn->state)) {
answer = 1;
break; /* stop looping, because we know the answer will be yes */
}
} SMARTLIST_FOREACH_END(dirconn);
smartlist_free(fetching_conns);
return answer;
}
/* Does the current, reasonably live consensus have IPv6 addresses?
* Returns 1 if there is a reasonably live consensus and its consensus method
* includes IPv6 addresses in the consensus.
* Otherwise, if there is no consensus, or the method does not include IPv6
* addresses, returns 0. */
int
networkstatus_consensus_has_ipv6(const or_options_t* options)
{
const networkstatus_t *cons = networkstatus_get_reasonably_live_consensus(
approx_time(),
usable_consensus_flavor());
/* If we have no consensus, we have no IPv6 in it */
if (!cons) {
return 0;
}
/* Different flavours of consensus gained IPv6 at different times */
if (we_use_microdescriptors_for_circuits(options)) {
return
cons->consensus_method >= MIN_METHOD_FOR_A_LINES_IN_MICRODESC_CONSENSUS;
} else {
return cons->consensus_method >= MIN_METHOD_FOR_A_LINES;
}
}
/** Given two router status entries for the same router identity, return 1 if
* if the contents have changed between them. Otherwise, return 0. */
static int
routerstatus_has_changed(const routerstatus_t *a, const routerstatus_t *b)
{
tor_assert(tor_memeq(a->identity_digest, b->identity_digest, DIGEST_LEN));
return strcmp(a->nickname, b->nickname) ||
fast_memneq(a->descriptor_digest, b->descriptor_digest, DIGEST_LEN) ||
a->addr != b->addr ||
a->or_port != b->or_port ||
a->dir_port != b->dir_port ||
a->is_authority != b->is_authority ||
a->is_exit != b->is_exit ||
a->is_stable != b->is_stable ||
a->is_fast != b->is_fast ||
a->is_flagged_running != b->is_flagged_running ||
a->is_named != b->is_named ||
a->is_unnamed != b->is_unnamed ||
a->is_valid != b->is_valid ||
a->is_possible_guard != b->is_possible_guard ||
a->is_bad_exit != b->is_bad_exit ||
a->is_hs_dir != b->is_hs_dir;
// XXXX this function needs a huge refactoring; it has gotten out
// XXXX of sync with routerstatus_t, and it will do so again.
}
/** Notify controllers of any router status entries that changed between
* old_c and new_c. */
static void
notify_control_networkstatus_changed(const networkstatus_t *old_c,
const networkstatus_t *new_c)
{
smartlist_t *changed;
if (old_c == new_c)
return;
/* tell the controller exactly which relays are still listed, as well
* as what they're listed as */
control_event_newconsensus(new_c);
if (!control_event_is_interesting(EVENT_NS))
return;
if (!old_c) {
control_event_networkstatus_changed(new_c->routerstatus_list);
return;
}
changed = smartlist_new();
SMARTLIST_FOREACH_JOIN(
old_c->routerstatus_list, const routerstatus_t *, rs_old,
new_c->routerstatus_list, const routerstatus_t *, rs_new,
tor_memcmp(rs_old->identity_digest,
rs_new->identity_digest, DIGEST_LEN),
smartlist_add(changed, (void*) rs_new)) {
if (routerstatus_has_changed(rs_old, rs_new))
smartlist_add(changed, (void*)rs_new);
} SMARTLIST_FOREACH_JOIN_END(rs_old, rs_new);
control_event_networkstatus_changed(changed);
smartlist_free(changed);
}
/* Called before the consensus changes from old_c to new_c. */
static void
notify_before_networkstatus_changes(const networkstatus_t *old_c,
const networkstatus_t *new_c)
{
notify_control_networkstatus_changed(old_c, new_c);
dos_consensus_has_changed(new_c);
}
/* Called after a new consensus has been put in the global state. It is safe
* to use the consensus getters in this function. */
static void
notify_after_networkstatus_changes(void)
{
scheduler_notify_networkstatus_changed();
}
/** Copy all the ancillary information (like router download status and so on)
* from old_c to new_c. */
static void
networkstatus_copy_old_consensus_info(networkstatus_t *new_c,
const networkstatus_t *old_c)
{
if (old_c == new_c)
return;
if (!old_c || !smartlist_len(old_c->routerstatus_list))
return;
SMARTLIST_FOREACH_JOIN(old_c->routerstatus_list, routerstatus_t *, rs_old,
new_c->routerstatus_list, routerstatus_t *, rs_new,
tor_memcmp(rs_old->identity_digest,
rs_new->identity_digest, DIGEST_LEN),
STMT_NIL) {
/* Okay, so we're looking at the same identity. */
rs_new->last_dir_503_at = rs_old->last_dir_503_at;
if (tor_memeq(rs_old->descriptor_digest, rs_new->descriptor_digest,
DIGEST256_LEN)) {
/* And the same descriptor too! */
memcpy(&rs_new->dl_status, &rs_old->dl_status,sizeof(download_status_t));
}
} SMARTLIST_FOREACH_JOIN_END(rs_old, rs_new);
}
#ifdef TOR_UNIT_TESTS
/**Accept a flavor consensus c without any additional
* validation. This is exclusively for unit tests.
* We copy any ancillary information from a pre-existing consensus
* and then free the current one and replace it with the newly
* provided instance. Returns -1 on unrecognized flavor, 0 otherwise.
*/
int
networkstatus_set_current_consensus_from_ns(networkstatus_t *c,
const char *flavor)
{
int flav = networkstatus_parse_flavor_name(flavor);
switch (flav) {
case FLAV_NS:
if (current_ns_consensus) {
networkstatus_copy_old_consensus_info(c, current_ns_consensus);
networkstatus_vote_free(current_ns_consensus);
}
current_ns_consensus = c;
break;
case FLAV_MICRODESC:
if (current_md_consensus) {
networkstatus_copy_old_consensus_info(c, current_md_consensus);
networkstatus_vote_free(current_md_consensus);
}
current_md_consensus = c;
break;
}
return current_md_consensus ? 0 : -1;
}
#endif /* defined(TOR_UNIT_TESTS) */
/**
* Return true if any option is set in options to make us behave
* as a client.
*
* XXXX If we need this elsewhere at any point, we should make it nonstatic
* XXXX and move it into another file.
*/
static int
any_client_port_set(const or_options_t *options)
{
return (options->SocksPort_set ||
options->TransPort_set ||
options->NATDPort_set ||
options->ControlPort_set ||
options->DNSPort_set ||
options->HTTPTunnelPort_set);
}
/**
* Helper for handle_missing_protocol_warning: handles either the
* client case (if is_client is set) or the server case otherwise.
*/
static void
handle_missing_protocol_warning_impl(const networkstatus_t *c,
int is_client)
{
char *protocol_warning = NULL;
int should_exit = networkstatus_check_required_protocols(c,
is_client,
&protocol_warning);
if (protocol_warning) {
tor_log(should_exit ? LOG_ERR : LOG_WARN,
LD_GENERAL,
"%s", protocol_warning);
}
if (should_exit) {
tor_assert_nonfatal(protocol_warning);
}
tor_free(protocol_warning);
if (should_exit)
exit(1); // XXXX bad exit: should return from main.
}
/** Called when we have received a networkstatus c. If there are
* any _required_ protocols we are missing, log an error and exit
* immediately. If there are any _recommended_ protocols we are missing,
* warn. */
static void
handle_missing_protocol_warning(const networkstatus_t *c,
const or_options_t *options)
{
const int is_server = server_mode(options);
const int is_client = any_client_port_set(options) || !is_server;
if (is_server)
handle_missing_protocol_warning_impl(c, 0);
if (is_client)
handle_missing_protocol_warning_impl(c, 1);
}
/** Try to replace the current cached v3 networkstatus with the one in
* consensus. If we don't have enough certificates to validate it,
* store it in consensus_waiting_for_certs and launch a certificate fetch.
*
* If flags & NSSET_FROM_CACHE, this networkstatus has come from the disk
* cache. If flags & NSSET_WAS_WAITING_FOR_CERTS, this networkstatus was
* already received, but we were waiting for certificates on it. If flags &
* NSSET_DONT_DOWNLOAD_CERTS, do not launch certificate downloads as needed.
* If flags & NSSET_ACCEPT_OBSOLETE, then we should be willing to take this
* consensus, even if it comes from many days in the past.
*
* If source_dir is non-NULL, it's the identity digest for a directory that
* we've just successfully retrieved a consensus or certificates from, so try
* it first to fetch any missing certificates.
*
* Return 0 on success, <0 on failure. On failure, caller should increment
* the failure count as appropriate.
*
* We return -1 for mild failures that don't need to be reported to the
* user, and -2 for more serious problems.
*/
int
networkstatus_set_current_consensus(const char *consensus,
const char *flavor,
unsigned flags,
const char *source_dir)
{
networkstatus_t *c=NULL;
int r, result = -1;
time_t now = approx_time();
const or_options_t *options = get_options();
char *unverified_fname = NULL, *consensus_fname = NULL;
int flav = networkstatus_parse_flavor_name(flavor);
const unsigned from_cache = flags & NSSET_FROM_CACHE;
const unsigned was_waiting_for_certs = flags & NSSET_WAS_WAITING_FOR_CERTS;
const unsigned dl_certs = !(flags & NSSET_DONT_DOWNLOAD_CERTS);
const unsigned accept_obsolete = flags & NSSET_ACCEPT_OBSOLETE;
const unsigned require_flavor = flags & NSSET_REQUIRE_FLAVOR;
const common_digests_t *current_digests = NULL;
consensus_waiting_for_certs_t *waiting = NULL;
time_t current_valid_after = 0;
int free_consensus = 1; /* Free 'c' at the end of the function */
int old_ewma_enabled;
int checked_protocols_already = 0;
if (flav < 0) {
/* XXXX we don't handle unrecognized flavors yet. */
log_warn(LD_BUG, "Unrecognized consensus flavor %s", flavor);
return -2;
}
/* Make sure it's parseable. */
c = networkstatus_parse_vote_from_string(consensus, NULL, NS_TYPE_CONSENSUS);
if (!c) {
log_warn(LD_DIR, "Unable to parse networkstatus consensus");
result = -2;
goto done;
}
if (from_cache && !was_waiting_for_certs) {
/* We previously stored this; check _now_ to make sure that version-kills
* really work. This happens even before we check signatures: we did so
* before when we stored this to disk. This does mean an attacker who can
* write to the datadir can make us not start: such an attacker could
* already harm us by replacing our guards, which would be worse. */
checked_protocols_already = 1;
handle_missing_protocol_warning(c, options);
}
if ((int)c->flavor != flav) {
/* This wasn't the flavor we thought we were getting. */
if (require_flavor) {
log_warn(LD_DIR, "Got consensus with unexpected flavor %s (wanted %s)",
networkstatus_get_flavor_name(c->flavor), flavor);
goto done;
}
flav = c->flavor;
flavor = networkstatus_get_flavor_name(flav);
}
if (flav != usable_consensus_flavor() &&
!we_want_to_fetch_flavor(options, flav)) {
/* This consensus is totally boring to us: we won't use it, we didn't want
* it, and we won't serve it. Drop it. */
goto done;
}
if (from_cache && !accept_obsolete &&
c->valid_until < now-OLD_ROUTER_DESC_MAX_AGE) {
log_info(LD_DIR, "Loaded an expired consensus. Discarding.");
goto done;
}
if (!strcmp(flavor, "ns")) {
consensus_fname = get_cachedir_fname("cached-consensus");
unverified_fname = get_cachedir_fname("unverified-consensus");
if (current_ns_consensus) {
current_digests = ¤t_ns_consensus->digests;
current_valid_after = current_ns_consensus->valid_after;
}
} else if (!strcmp(flavor, "microdesc")) {
consensus_fname = get_cachedir_fname("cached-microdesc-consensus");
unverified_fname = get_cachedir_fname("unverified-microdesc-consensus");
if (current_md_consensus) {
current_digests = ¤t_md_consensus->digests;
current_valid_after = current_md_consensus->valid_after;
}
} else {
cached_dir_t *cur;
char buf[128];
tor_snprintf(buf, sizeof(buf), "cached-%s-consensus", flavor);
consensus_fname = get_cachedir_fname(buf);
tor_snprintf(buf, sizeof(buf), "unverified-%s-consensus", flavor);
unverified_fname = get_cachedir_fname(buf);
cur = dirserv_get_consensus(flavor);
if (cur) {
current_digests = &cur->digests;
current_valid_after = cur->published;
}
}
if (current_digests &&
tor_memeq(&c->digests, current_digests, sizeof(c->digests))) {
/* We already have this one. That's a failure. */
log_info(LD_DIR, "Got a %s consensus we already have", flavor);
goto done;
}
if (current_valid_after && c->valid_after <= current_valid_after) {
/* We have a newer one. There's no point in accepting this one,
* even if it's great. */
log_info(LD_DIR, "Got a %s consensus at least as old as the one we have",
flavor);
goto done;
}
/* Make sure it's signed enough. */
if ((r=networkstatus_check_consensus_signature(c, 1))<0) {
if (r == -1) {
/* Okay, so it _might_ be signed enough if we get more certificates. */
if (!was_waiting_for_certs) {
log_info(LD_DIR,
"Not enough certificates to check networkstatus consensus");
}
if (!current_valid_after ||
c->valid_after > current_valid_after) {
waiting = &consensus_waiting_for_certs[flav];
networkstatus_vote_free(waiting->consensus);
tor_free(waiting->body);
waiting->consensus = c;
free_consensus = 0;
waiting->body = tor_strdup(consensus);
waiting->set_at = now;
waiting->dl_failed = 0;
if (!from_cache) {
write_str_to_file(unverified_fname, consensus, 0);
}
if (dl_certs)
authority_certs_fetch_missing(c, now, source_dir);
/* This case is not a success or a failure until we get the certs
* or fail to get the certs. */
result = 0;
} else {
/* Even if we had enough signatures, we'd never use this as the
* latest consensus. */
if (was_waiting_for_certs && from_cache)
if (unlink(unverified_fname) != 0) {
log_warn(LD_FS,
"Failed to unlink %s: %s",
unverified_fname, strerror(errno));
}
}
goto done;
} else {
/* This can never be signed enough: Kill it. */
if (!was_waiting_for_certs) {
log_warn(LD_DIR, "Not enough good signatures on networkstatus "
"consensus");
result = -2;
}
if (was_waiting_for_certs && (r < -1) && from_cache) {
if (unlink(unverified_fname) != 0) {
log_warn(LD_FS,
"Failed to unlink %s: %s",
unverified_fname, strerror(errno));
}
}
goto done;
}
}
if (!from_cache && flav == usable_consensus_flavor())
control_event_client_status(LOG_NOTICE, "CONSENSUS_ARRIVED");
if (!checked_protocols_already) {
handle_missing_protocol_warning(c, options);
}
/* Are we missing any certificates at all? */
if (r != 1 && dl_certs)
authority_certs_fetch_missing(c, now, source_dir);
const int is_usable_flavor = flav == usable_consensus_flavor();
/* Before we switch to the new consensus, notify that we are about to change
* it using the old consensus and the new one. */
if (is_usable_flavor) {
notify_before_networkstatus_changes(networkstatus_get_latest_consensus(),
c);
}
if (flav == FLAV_NS) {
if (current_ns_consensus) {
networkstatus_copy_old_consensus_info(c, current_ns_consensus);
networkstatus_vote_free(current_ns_consensus);
/* Defensive programming : we should set current_ns_consensus very soon
* but we're about to call some stuff in the meantime, and leaving this
* dangling pointer around has proven to be trouble. */
current_ns_consensus = NULL;
}
current_ns_consensus = c;
free_consensus = 0; /* avoid free */
} else if (flav == FLAV_MICRODESC) {
if (current_md_consensus) {
networkstatus_copy_old_consensus_info(c, current_md_consensus);
networkstatus_vote_free(current_md_consensus);
/* more defensive programming */
current_md_consensus = NULL;
}
current_md_consensus = c;
free_consensus = 0; /* avoid free */
}
waiting = &consensus_waiting_for_certs[flav];
if (waiting->consensus &&
waiting->consensus->valid_after <= c->valid_after) {
networkstatus_vote_free(waiting->consensus);
waiting->consensus = NULL;
if (consensus != waiting->body)
tor_free(waiting->body);
else
waiting->body = NULL;
waiting->set_at = 0;
waiting->dl_failed = 0;
if (unlink(unverified_fname) != 0) {
log_warn(LD_FS,
"Failed to unlink %s: %s",
unverified_fname, strerror(errno));
}
}
if (is_usable_flavor) {
/* Notify that we just changed the consensus so the current global value
* can be looked at. */
notify_after_networkstatus_changes();
/* The "current" consensus has just been set and it is a usable flavor so
* the first thing we need to do is recalculate the voting schedule static
* object so we can use the timings in there needed by some subsystems
* such as hidden service and shared random. */
dirvote_recalculate_timing(options, now);
nodelist_set_consensus(c);
/* XXXXNM Microdescs: needs a non-ns variant. ???? NM*/
update_consensus_networkstatus_fetch_time(now);
/* Update ewma and adjust policy if needed; first cache the old value */
old_ewma_enabled = cell_ewma_enabled();
/* Change the cell EWMA settings */
cell_ewma_set_scale_factor(options, c);
/* If we just enabled ewma, set the cmux policy on all active channels */
if (cell_ewma_enabled() && !old_ewma_enabled) {
channel_set_cmux_policy_everywhere(&ewma_policy);
} else if (!cell_ewma_enabled() && old_ewma_enabled) {
/* Turn it off everywhere */
channel_set_cmux_policy_everywhere(NULL);
}
/* XXXX this call might be unnecessary here: can changing the
* current consensus really alter our view of any OR's rate limits? */
connection_or_update_token_buckets(get_connection_array(), options);
circuit_build_times_new_consensus_params(
get_circuit_build_times_mutable(), c);
channelpadding_new_consensus_params(c);
}
/* Reset the failure count only if this consensus is actually valid. */
if (c->valid_after <= now && now <= c->valid_until) {
download_status_reset(&consensus_dl_status[flav]);
} else {
if (!from_cache)
download_status_failed(&consensus_dl_status[flav], 0);
}
if (we_want_to_fetch_flavor(options, flav)) {
dirserv_set_cached_consensus_networkstatus(consensus,
flavor,
&c->digests,
c->digest_sha3_as_signed,
c->valid_after);
if (dir_server_mode(get_options())) {
consdiffmgr_add_consensus(consensus, c);
}
}
if (!from_cache) {
write_str_to_file(consensus_fname, consensus, 0);
}
/** If a consensus appears more than this many seconds before its declared
* valid-after time, declare that our clock is skewed. */
#define EARLY_CONSENSUS_NOTICE_SKEW 60
if (now < c->valid_after - EARLY_CONSENSUS_NOTICE_SKEW) {
char tbuf[ISO_TIME_LEN+1];
char dbuf[64];
long delta = now - c->valid_after;
char *flavormsg = NULL;
format_iso_time(tbuf, c->valid_after);
format_time_interval(dbuf, sizeof(dbuf), delta);
log_warn(LD_GENERAL, "Our clock is %s behind the time published in the "
"consensus network status document (%s UTC). Tor needs an "
"accurate clock to work correctly. Please check your time and "
"date settings!", dbuf, tbuf);
tor_asprintf(&flavormsg, "%s flavor consensus", flavor);
clock_skew_warning(NULL, delta, 1, LD_GENERAL, flavormsg, "CONSENSUS");
tor_free(flavormsg);
}
/* We got a new consesus. Reset our md fetch fail cache */
microdesc_reset_outdated_dirservers_list();
router_dir_info_changed();
result = 0;
done:
if (free_consensus)
networkstatus_vote_free(c);
tor_free(consensus_fname);
tor_free(unverified_fname);
return result;
}
/** Called when we have gotten more certificates: see whether we can
* now verify a pending consensus.
*
* If source_dir is non-NULL, it's the identity digest for a directory that
* we've just successfully retrieved certificates from, so try it first to
* fetch any missing certificates.
*/
void
networkstatus_note_certs_arrived(const char *source_dir)
{
int i;
for (i=0; iconsensus)
continue;
if (networkstatus_check_consensus_signature(waiting->consensus, 0)>=0) {
char *waiting_body = waiting->body;
if (!networkstatus_set_current_consensus(
waiting_body,
flavor_name,
NSSET_WAS_WAITING_FOR_CERTS,
source_dir)) {
tor_free(waiting_body);
}
}
}
}
/** If the network-status list has changed since the last time we called this
* function, update the status of every routerinfo from the network-status
* list. If dir_version is 2, it's a v2 networkstatus that changed.
* If dir_version is 3, it's a v3 consensus that changed.
*/
void
routers_update_all_from_networkstatus(time_t now, int dir_version)
{
routerlist_t *rl = router_get_routerlist();
networkstatus_t *consensus = networkstatus_get_reasonably_live_consensus(now,
FLAV_NS);
if (!consensus || dir_version < 3) /* nothing more we should do */
return;
/* calls router_dir_info_changed() when it's done -- more routers
* might be up or down now, which might affect whether there's enough
* directory info. */
routers_update_status_from_consensus_networkstatus(rl->routers, 0);
SMARTLIST_FOREACH(rl->routers, routerinfo_t *, ri,
ri->cache_info.routerlist_index = ri_sl_idx);
if (rl->old_routers)
signed_descs_update_status_from_consensus_networkstatus(rl->old_routers);
if (!have_warned_about_old_version) {
int is_server = server_mode(get_options());
version_status_t status;
const char *recommended = is_server ?
consensus->server_versions : consensus->client_versions;
status = tor_version_is_obsolete(VERSION, recommended);
if (status == VS_RECOMMENDED) {
log_info(LD_GENERAL, "The directory authorities say my version is ok.");
} else if (status == VS_EMPTY) {
log_info(LD_GENERAL,
"The directory authorities don't recommend any versions.");
} else if (status == VS_NEW || status == VS_NEW_IN_SERIES) {
if (!have_warned_about_new_version) {
log_notice(LD_GENERAL, "This version of Tor (%s) is newer than any "
"recommended version%s, according to the directory "
"authorities. Recommended versions are: %s",
VERSION,
status == VS_NEW_IN_SERIES ? " in its series" : "",
recommended);
have_warned_about_new_version = 1;
control_event_general_status(LOG_WARN, "DANGEROUS_VERSION "
"CURRENT=%s REASON=%s RECOMMENDED=\"%s\"",
VERSION, "NEW", recommended);
}
} else {
log_warn(LD_GENERAL, "Please upgrade! "
"This version of Tor (%s) is %s, according to the directory "
"authorities. Recommended versions are: %s",
VERSION,
status == VS_OLD ? "obsolete" : "not recommended",
recommended);
have_warned_about_old_version = 1;
control_event_general_status(LOG_WARN, "DANGEROUS_VERSION "
"CURRENT=%s REASON=%s RECOMMENDED=\"%s\"",
VERSION, status == VS_OLD ? "OBSOLETE" : "UNRECOMMENDED",
recommended);
}
}
}
/** Given a list routers of routerinfo_t *, update each status field
* according to our current consensus networkstatus. May re-order
* routers. */
void
routers_update_status_from_consensus_networkstatus(smartlist_t *routers,
int reset_failures)
{
const or_options_t *options = get_options();
int authdir = authdir_mode_v3(options);
networkstatus_t *ns = networkstatus_get_latest_consensus();
if (!ns || !smartlist_len(ns->routerstatus_list))
return;
routers_sort_by_identity(routers);
SMARTLIST_FOREACH_JOIN(ns->routerstatus_list, routerstatus_t *, rs,
routers, routerinfo_t *, router,
tor_memcmp(rs->identity_digest,
router->cache_info.identity_digest, DIGEST_LEN),
{
}) {
/* Is it the same descriptor, or only the same identity? */
if (tor_memeq(router->cache_info.signed_descriptor_digest,
rs->descriptor_digest, DIGEST_LEN)) {
if (ns->valid_until > router->cache_info.last_listed_as_valid_until)
router->cache_info.last_listed_as_valid_until = ns->valid_until;
}
if (authdir) {
/* If we _are_ an authority, we should check whether this router
* is one that will cause us to need a reachability test. */
routerinfo_t *old_router =
router_get_mutable_by_digest(router->cache_info.identity_digest);
if (old_router != router) {
router->needs_retest_if_added =
dirserv_should_launch_reachability_test(router, old_router);
}
}
if (reset_failures) {
download_status_reset(&rs->dl_status);
}
} SMARTLIST_FOREACH_JOIN_END(rs, router);
router_dir_info_changed();
}
/** Given a list of signed_descriptor_t, update their fields (mainly, when
* they were last listed) from the most recent consensus. */
void
signed_descs_update_status_from_consensus_networkstatus(smartlist_t *descs)
{
networkstatus_t *ns = current_ns_consensus;
if (!ns)
return;
if (!ns->desc_digest_map) {
char dummy[DIGEST_LEN];
/* instantiates the digest map. */
memset(dummy, 0, sizeof(dummy));
router_get_consensus_status_by_descriptor_digest(ns, dummy);
}
SMARTLIST_FOREACH(descs, signed_descriptor_t *, d,
{
const routerstatus_t *rs = digestmap_get(ns->desc_digest_map,
d->signed_descriptor_digest);
if (rs) {
if (ns->valid_until > d->last_listed_as_valid_until)
d->last_listed_as_valid_until = ns->valid_until;
}
});
}
/** Generate networkstatus lines for a single routerstatus_t object, and
* return the result in a newly allocated string. Used only by controller
* interface (for now.) */
char *
networkstatus_getinfo_helper_single(const routerstatus_t *rs)
{
return routerstatus_format_entry(rs, NULL, NULL, NS_CONTROL_PORT,
ROUTERSTATUS_FORMAT_NO_CONSENSUS_METHOD,
NULL);
}
/** Alloc and return a string describing routerstatuses for the most
* recent info of each router we know about that is of purpose
* purpose_string. Return NULL if unrecognized purpose.
*
* Right now this function is oriented toward listing bridges (you
* shouldn't use this for general-purpose routers, since those
* should be listed from the consensus, not from the routers list). */
char *
networkstatus_getinfo_by_purpose(const char *purpose_string, time_t now)
{
const time_t cutoff = now - ROUTER_MAX_AGE_TO_PUBLISH;
char *answer;
routerlist_t *rl = router_get_routerlist();
smartlist_t *statuses;
const uint8_t purpose = router_purpose_from_string(purpose_string);
routerstatus_t rs;
const int bridge_auth = authdir_mode_bridge(get_options());
if (purpose == ROUTER_PURPOSE_UNKNOWN) {
log_info(LD_DIR, "Unrecognized purpose '%s' when listing router statuses.",
purpose_string);
return NULL;
}
statuses = smartlist_new();
SMARTLIST_FOREACH_BEGIN(rl->routers, routerinfo_t *, ri) {
node_t *node = node_get_mutable_by_id(ri->cache_info.identity_digest);
if (!node)
continue;
if (ri->cache_info.published_on < cutoff)
continue;
if (ri->purpose != purpose)
continue;
/* TODO: modifying the running flag in a getinfo is a bad idea */
if (bridge_auth && ri->purpose == ROUTER_PURPOSE_BRIDGE)
dirserv_set_router_is_running(ri, now);
/* then generate and write out status lines for each of them */
set_routerstatus_from_routerinfo(&rs, node, ri, now, 0);
smartlist_add(statuses, networkstatus_getinfo_helper_single(&rs));
} SMARTLIST_FOREACH_END(ri);
answer = smartlist_join_strings(statuses, "", 0, NULL);
SMARTLIST_FOREACH(statuses, char *, cp, tor_free(cp));
smartlist_free(statuses);
return answer;
}
/** Write out router status entries for all our bridge descriptors. */
void
networkstatus_dump_bridge_status_to_file(time_t now)
{
char *status = networkstatus_getinfo_by_purpose("bridge", now);
char *fname = NULL;
char *thresholds = NULL;
char *published_thresholds_and_status = NULL;
char published[ISO_TIME_LEN+1];
const routerinfo_t *me = router_get_my_routerinfo();
char fingerprint[FINGERPRINT_LEN+1];
char *fingerprint_line = NULL;
if (me && crypto_pk_get_fingerprint(me->identity_pkey,
fingerprint, 0) >= 0) {
tor_asprintf(&fingerprint_line, "fingerprint %s\n", fingerprint);
} else {
log_warn(LD_BUG, "Error computing fingerprint for bridge status.");
}
format_iso_time(published, now);
dirserv_compute_bridge_flag_thresholds();
thresholds = dirserv_get_flag_thresholds_line();
tor_asprintf(&published_thresholds_and_status,
"published %s\nflag-thresholds %s\n%s%s",
published, thresholds, fingerprint_line ? fingerprint_line : "",
status);
fname = get_datadir_fname("networkstatus-bridges");
write_str_to_file(fname,published_thresholds_and_status,0);
tor_free(thresholds);
tor_free(published_thresholds_and_status);
tor_free(fname);
tor_free(status);
tor_free(fingerprint_line);
}
/* DOCDOC get_net_param_from_list */
static int32_t
get_net_param_from_list(smartlist_t *net_params, const char *param_name,
int32_t default_val, int32_t min_val, int32_t max_val)
{
int32_t res = default_val;
size_t name_len = strlen(param_name);
tor_assert(max_val > min_val);
tor_assert(min_val <= default_val);
tor_assert(max_val >= default_val);
SMARTLIST_FOREACH_BEGIN(net_params, const char *, p) {
if (!strcmpstart(p, param_name) && p[name_len] == '=') {
int ok=0;
long v = tor_parse_long(p+name_len+1, 10, INT32_MIN,
INT32_MAX, &ok, NULL);
if (ok) {
res = (int32_t) v;
break;
}
}
} SMARTLIST_FOREACH_END(p);
if (res < min_val) {
log_warn(LD_DIR, "Consensus parameter %s is too small. Got %d, raising to "
"%d.", param_name, res, min_val);
res = min_val;
} else if (res > max_val) {
log_warn(LD_DIR, "Consensus parameter %s is too large. Got %d, capping to "
"%d.", param_name, res, max_val);
res = max_val;
}
return res;
}
/** Return the value of a integer parameter from the networkstatus ns
* whose name is param_name. If ns is NULL, try loading the
* latest consensus ourselves. Return default_val if no latest
* consensus, or if it has no parameter called param_name.
* Make sure the value parsed from the consensus is at least
* min_val and at most max_val and raise/cap the parsed value
* if necessary. */
MOCK_IMPL(int32_t,
networkstatus_get_param, (const networkstatus_t *ns, const char *param_name,
int32_t default_val, int32_t min_val, int32_t max_val))
{
if (!ns) /* if they pass in null, go find it ourselves */
ns = networkstatus_get_latest_consensus();
if (!ns || !ns->net_params)
return default_val;
return get_net_param_from_list(ns->net_params, param_name,
default_val, min_val, max_val);
}
/**
* As networkstatus_get_param(), but check torrc_value before checking the
* consensus. If torrc_value is in-range, then return it instead of the
* value from the consensus.
*/
int32_t
networkstatus_get_overridable_param(const networkstatus_t *ns,
int32_t torrc_value,
const char *param_name,
int32_t default_val,
int32_t min_val, int32_t max_val)
{
if (torrc_value >= min_val && torrc_value <= max_val)
return torrc_value;
else
return networkstatus_get_param(
ns, param_name, default_val, min_val, max_val);
}
/**
* Retrieve the consensus parameter that governs the
* fixed-point precision of our network balancing 'bandwidth-weights'
* (which are themselves integer consensus values). We divide them
* by this value and ensure they never exceed this value.
*/
int
networkstatus_get_weight_scale_param(networkstatus_t *ns)
{
return networkstatus_get_param(ns, "bwweightscale",
BW_WEIGHT_SCALE,
BW_MIN_WEIGHT_SCALE,
BW_MAX_WEIGHT_SCALE);
}
/** Return the value of a integer bw weight parameter from the networkstatus
* ns whose name is weight_name. If ns is NULL, try
* loading the latest consensus ourselves. Return default_val if no
* latest consensus, or if it has no parameter called weight_name. */
int32_t
networkstatus_get_bw_weight(networkstatus_t *ns, const char *weight_name,
int32_t default_val)
{
int32_t param;
int max;
if (!ns) /* if they pass in null, go find it ourselves */
ns = networkstatus_get_latest_consensus();
if (!ns || !ns->weight_params)
return default_val;
max = networkstatus_get_weight_scale_param(ns);
param = get_net_param_from_list(ns->weight_params, weight_name,
default_val, -1,
BW_MAX_WEIGHT_SCALE);
if (param > max) {
log_warn(LD_DIR, "Value of consensus weight %s was too large, capping "
"to %d", weight_name, max);
param = max;
}
return param;
}
/** Return the name of the consensus flavor flav as used to identify
* the flavor in directory documents. */
const char *
networkstatus_get_flavor_name(consensus_flavor_t flav)
{
switch (flav) {
case FLAV_NS:
return "ns";
case FLAV_MICRODESC:
return "microdesc";
default:
tor_fragile_assert();
return "??";
}
}
/** Return the consensus_flavor_t value for the flavor called flavname,
* or -1 if the flavor is not recognized. */
int
networkstatus_parse_flavor_name(const char *flavname)
{
if (!strcmp(flavname, "ns"))
return FLAV_NS;
else if (!strcmp(flavname, "microdesc"))
return FLAV_MICRODESC;
else
return -1;
}
/** Return 0 if this routerstatus is obsolete, too new, isn't
* running, or otherwise not a descriptor that we would make any
* use of even if we had it. Else return 1. */
int
client_would_use_router(const routerstatus_t *rs, time_t now)
{
if (!rs->is_flagged_running) {
/* If we had this router descriptor, we wouldn't even bother using it.
* (Fetching and storing depends on by we_want_to_fetch_flavor().) */
return 0;
}
if (rs->published_on + OLD_ROUTER_DESC_MAX_AGE < now) {
/* We'd drop it immediately for being too old. */
return 0;
}
if (!routerstatus_version_supports_extend2_cells(rs, 1)) {
/* We'd ignore it because it doesn't support EXTEND2 cells.
* If we don't know the version, download the descriptor so we can
* check if it supports EXTEND2 cells and ntor. */
return 0;
}
return 1;
}
/** If question is a string beginning with "ns/" in a format the
* control interface expects for a GETINFO question, set *answer to a
* newly-allocated string containing networkstatus lines for the appropriate
* ORs. Return 0 on success, -1 on unrecognized question format. */
int
getinfo_helper_networkstatus(control_connection_t *conn,
const char *question, char **answer,
const char **errmsg)
{
const routerstatus_t *status;
(void) conn;
if (!networkstatus_get_latest_consensus()) {
*answer = tor_strdup("");
return 0;
}
if (!strcmp(question, "ns/all")) {
smartlist_t *statuses = smartlist_new();
SMARTLIST_FOREACH(networkstatus_get_latest_consensus()->routerstatus_list,
const routerstatus_t *, rs,
{
smartlist_add(statuses, networkstatus_getinfo_helper_single(rs));
});
*answer = smartlist_join_strings(statuses, "", 0, NULL);
SMARTLIST_FOREACH(statuses, char *, cp, tor_free(cp));
smartlist_free(statuses);
return 0;
} else if (!strcmpstart(question, "ns/id/")) {
char d[DIGEST_LEN];
const char *q = question + 6;
if (*q == '$')
++q;
if (base16_decode(d, DIGEST_LEN, q, strlen(q)) != DIGEST_LEN) {
*errmsg = "Data not decodeable as hex";
return -1;
}
status = router_get_consensus_status_by_id(d);
} else if (!strcmpstart(question, "ns/name/")) {
const node_t *n = node_get_by_nickname(question+8, 0);
status = n ? n->rs : NULL;
} else if (!strcmpstart(question, "ns/purpose/")) {
*answer = networkstatus_getinfo_by_purpose(question+11, time(NULL));
return *answer ? 0 : -1;
} else if (!strcmp(question, "consensus/packages")) {
const networkstatus_t *ns = networkstatus_get_latest_consensus();
if (ns && ns->package_lines)
*answer = smartlist_join_strings(ns->package_lines, "\n", 0, NULL);
else
*errmsg = "No consensus available";
return *answer ? 0 : -1;
} else if (!strcmp(question, "consensus/valid-after") ||
!strcmp(question, "consensus/fresh-until") ||
!strcmp(question, "consensus/valid-until")) {
const networkstatus_t *ns = networkstatus_get_latest_consensus();
if (ns) {
time_t t;
if (!strcmp(question, "consensus/valid-after"))
t = ns->valid_after;
else if (!strcmp(question, "consensus/fresh-until"))
t = ns->fresh_until;
else
t = ns->valid_until;
char tbuf[ISO_TIME_LEN+1];
format_iso_time(tbuf, t);
*answer = tor_strdup(tbuf);
} else {
*errmsg = "No consensus available";
}
return *answer ? 0 : -1;
} else {
return 0;
}
if (status)
*answer = networkstatus_getinfo_helper_single(status);
return 0;
}
/** Check whether the networkstatus ns lists any protocol
* versions as "required" or "recommended" that we do not support. If
* so, set *warning_out to a newly allocated string describing
* the problem.
*
* Return 1 if we should exit, 0 if we should not. */
int
networkstatus_check_required_protocols(const networkstatus_t *ns,
int client_mode,
char **warning_out)
{
const char *func = client_mode ? "client" : "relay";
const char *required, *recommended;
char *missing = NULL;
tor_assert(warning_out);
if (client_mode) {
required = ns->required_client_protocols;
recommended = ns->recommended_client_protocols;
} else {
required = ns->required_relay_protocols;
recommended = ns->recommended_relay_protocols;
}
if (!protover_all_supported(required, &missing)) {
tor_asprintf(warning_out, "At least one protocol listed as required in "
"the consensus is not supported by this version of Tor. "
"You should upgrade. This version of Tor will not work as a "
"%s on the Tor network. The missing protocols are: %s",
func, missing);
tor_free(missing);
return 1;
}
if (! protover_all_supported(recommended, &missing)) {
tor_asprintf(warning_out, "At least one protocol listed as recommended in "
"the consensus is not supported by this version of Tor. "
"You should upgrade. This version of Tor will eventually "
"stop working as a %s on the Tor network. The missing "
"protocols are: %s",
func, missing);
tor_free(missing);
}
tor_assert_nonfatal(missing == NULL);
return 0;
}
/** Free all storage held locally in this module. */
void
networkstatus_free_all(void)
{
int i;
networkstatus_vote_free(current_ns_consensus);
networkstatus_vote_free(current_md_consensus);
current_md_consensus = current_ns_consensus = NULL;
for (i=0; i < N_CONSENSUS_FLAVORS; ++i) {
consensus_waiting_for_certs_t *waiting = &consensus_waiting_for_certs[i];
if (waiting->consensus) {
networkstatus_vote_free(waiting->consensus);
waiting->consensus = NULL;
}
tor_free(waiting->body);
}
}