diff options
Diffstat (limited to 'src/or/microdesc.c')
| -rw-r--r-- | src/or/microdesc.c | 134 |
1 files changed, 106 insertions, 28 deletions
diff --git a/src/or/microdesc.c b/src/or/microdesc.c index a81dc54628..fe327c6c82 100644 --- a/src/or/microdesc.c +++ b/src/or/microdesc.c @@ -1,4 +1,4 @@ -/* Copyright (c) 2009-2016, The Tor Project, Inc. */ +/* Copyright (c) 2009-2017, The Tor Project, Inc. */ /* See LICENSE for licensing information */ /** @@ -74,6 +74,102 @@ HT_GENERATE2(microdesc_map, microdesc_t, node, microdesc_hash_, microdesc_eq_, 0.6, tor_reallocarray_, tor_free_) +/************************* md fetch fail cache *****************************/ + +/* If we end up with too many outdated dirservers, something probably went + * wrong so clean up the list. */ +#define TOO_MANY_OUTDATED_DIRSERVERS 30 + +/** List of dirservers with outdated microdesc information. The smartlist is + * filled with the hex digests of outdated dirservers. */ +static smartlist_t *outdated_dirserver_list = NULL; + +/** Note that we failed to fetch a microdescriptor from the relay with + * <b>relay_digest</b> (of size DIGEST_LEN). */ +void +microdesc_note_outdated_dirserver(const char *relay_digest) +{ + char relay_hexdigest[HEX_DIGEST_LEN+1]; + + /* Don't register outdated dirservers if we don't have a live consensus, + * since we might be trying to fetch microdescriptors that are not even + * currently active. */ + if (!networkstatus_get_live_consensus(approx_time())) { + return; + } + + if (!outdated_dirserver_list) { + outdated_dirserver_list = smartlist_new(); + } + + tor_assert(outdated_dirserver_list); + + /* If the list grows too big, clean it up */ + if (BUG(smartlist_len(outdated_dirserver_list) > + TOO_MANY_OUTDATED_DIRSERVERS)) { + microdesc_reset_outdated_dirservers_list(); + } + + /* Turn the binary relay digest to a hex since smartlists have better support + * for strings than digests. */ + base16_encode(relay_hexdigest,sizeof(relay_hexdigest), + relay_digest, DIGEST_LEN); + + /* Make sure we don't add a dirauth as an outdated dirserver */ + if (router_get_trusteddirserver_by_digest(relay_digest)) { + log_info(LD_GENERAL, "Auth %s gave us outdated dirinfo.", relay_hexdigest); + return; + } + + /* Don't double-add outdated dirservers */ + if (smartlist_contains_string(outdated_dirserver_list, relay_hexdigest)) { + return; + } + + /* Add it to the list of outdated dirservers */ + smartlist_add_strdup(outdated_dirserver_list, relay_hexdigest); + + log_info(LD_GENERAL, "Noted %s as outdated md dirserver", relay_hexdigest); +} + +/** Return True if the relay with <b>relay_digest</b> (size DIGEST_LEN) is an + * outdated dirserver */ +int +microdesc_relay_is_outdated_dirserver(const char *relay_digest) +{ + char relay_hexdigest[HEX_DIGEST_LEN+1]; + + if (!outdated_dirserver_list) { + return 0; + } + + /* Convert identity digest to hex digest */ + base16_encode(relay_hexdigest, sizeof(relay_hexdigest), + relay_digest, DIGEST_LEN); + + /* Last time we tried to fetch microdescs, was this directory mirror missing + * any mds we asked for? */ + if (smartlist_contains_string(outdated_dirserver_list, relay_hexdigest)) { + return 1; + } + + return 0; +} + +/** Reset the list of outdated dirservers. */ +void +microdesc_reset_outdated_dirservers_list(void) +{ + if (!outdated_dirserver_list) { + return; + } + + SMARTLIST_FOREACH(outdated_dirserver_list, char *, cp, tor_free(cp)); + smartlist_clear(outdated_dirserver_list); +} + +/****************************************************************************/ + /** Write the body of <b>md</b> into <b>f</b>, with appropriate annotations. * On success, return the total number of bytes written, and set * *<b>annotation_len_out</b> to the number of bytes written as @@ -789,6 +885,11 @@ microdesc_free_all(void) tor_free(the_microdesc_cache->journal_fname); tor_free(the_microdesc_cache); } + + if (outdated_dirserver_list) { + SMARTLIST_FOREACH(outdated_dirserver_list, char *, cp, tor_free(cp)); + smartlist_free(outdated_dirserver_list); + } } /** If there is a microdescriptor in <b>cache</b> whose sha256 digest is @@ -804,18 +905,6 @@ microdesc_cache_lookup_by_digest256(microdesc_cache_t *cache, const char *d) return md; } -/** Return the mean size of decriptors added to <b>cache</b> since it was last - * cleared. Used to estimate the size of large downloads. */ -size_t -microdesc_average_size(microdesc_cache_t *cache) -{ - if (!cache) - cache = get_microdesc_cache(); - if (!cache->n_seen) - return 512; - return (size_t)(cache->total_len_seen / cache->n_seen); -} - /** Return a smartlist of all the sha256 digest of the microdescriptors that * are listed in <b>ns</b> but not present in <b>cache</b>. Returns pointers * to internals of <b>ns</b>; you should not free the members of the resulting @@ -888,7 +977,7 @@ update_microdesc_downloads(time_t now) smartlist_free(missing); } -/** For every microdescriptor listed in the current microdecriptor consensus, +/** For every microdescriptor listed in the current microdescriptor consensus, * update its last_listed field to be at least as recent as the publication * time of the current microdescriptor consensus. */ @@ -917,20 +1006,9 @@ update_microdescs_from_networkstatus(time_t now) int we_use_microdescriptors_for_circuits(const or_options_t *options) { - int ret = options->UseMicrodescriptors; - if (ret == -1) { - /* UseMicrodescriptors is "auto"; we need to decide: */ - /* If we are configured to use bridges and none of our bridges - * know what a microdescriptor is, the answer is no. */ - if (options->UseBridges && !any_bridge_supports_microdescriptors()) - return 0; - /* Otherwise, we decide that we'll use microdescriptors iff we are - * not a server, and we're not autofetching everything. */ - /* XXXX++ what does not being a server have to do with it? also there's - * a partitioning issue here where bridges differ from clients. */ - ret = !server_mode(options) && !options->FetchUselessDescriptors; - } - return ret; + if (options->UseMicrodescriptors == 0) + return 0; /* the user explicitly picked no */ + return 1; /* yes and auto both mean yes */ } /** Return true iff we should try to download microdescriptors at all. */ |