November 2017 - tor-commits - lists.torproject.org

[tor/master] Skip dirserver restrictions in small networks.
by nickm＠torproject.org 17 Nov '17

17 Nov '17

commit c400ffc2e88dab54b070a856717fb0ee6fe096cb Author: George Kadianakis <desnacked(a)riseup.net> Date: Mon Nov 13 22:26:22 2017 +0200 Skip dirserver restrictions in small networks. --- src/or/entrynodes.c | 42 ++++++++++++++++++++++++++++++++++-------- 1 file changed, 34 insertions(+), 8 deletions(-) diff --git a/src/or/entrynodes.c b/src/or/entrynodes.c index f2ca7aac2..1cc24d8d6 100644 --- a/src/or/entrynodes.c +++ b/src/or/entrynodes.c @@ -1472,12 +1472,45 @@ guard_create_exit_restriction(const uint8_t *exit_id) return rst; } -/** Allocate and return an outdated md guard restriction. */ +/** If we have less than these many configured bridges, don't set dirserver + * restrictions because we might blacklist all of them. */ +#define TOO_FEW_BRIDGES_FOR_RESTRICTION 10 + +/** Return true if we should set md dirserver restrictions. We might not want + * to set those if our network is too restricted, since we don't want to + * blacklist all our nodes. */ +static int +should_set_md_dirserver_restriction(void) +{ + const guard_selection_t *gs = get_guard_selection_info(); + + /* Don't set a restriction if we are on a restricted guard selection */ + if (gs->type == GS_TYPE_RESTRICTED) { + return 0; + } + + /* Don't set restriction if we are using bridges and have too few of those */ + if (gs->type == GS_TYPE_BRIDGE && gs->sampled_entry_guards) { + int num_sampled_guards = smartlist_len(gs->sampled_entry_guards); + if (num_sampled_guards < TOO_FEW_BRIDGES_FOR_RESTRICTION) { + return 0; + } + } + + return 1; +} + +/** Allocate and return an outdated md guard restriction. Return NULL if no + * such restriction is needed. */ STATIC entry_guard_restriction_t * guard_create_dirserver_md_restriction(void) { entry_guard_restriction_t *rst = NULL; + if (!should_set_md_dirserver_restriction()) { + return NULL; + } + rst = tor_malloc_zero(sizeof(entry_guard_restriction_t)); rst->type = RST_OUTDATED_MD_DIRSERVER; @@ -1504,13 +1537,6 @@ guard_obeys_exit_restriction(const entry_guard_t *guard, static int guard_obeys_md_dirserver_restriction(const entry_guard_t *guard) { - /* Don't enforce dirserver restrictions for bridges since we might not have - * many of those. Be willing to try them over and over again for now. */ - /* XXX: Improvement might be possible here */ - if (guard->bridge_addr) { - return 1; - } - /* If this guard is an outdated dirserver, don't use it. */ if (microdesc_relay_is_outdated_dirserver(guard->identity)) { log_info(LD_GENERAL, "Skipping %s dirserver: outdated",

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[tor/master] Merge branch 'bug23817_031' into maint-0.3.2
by nickm＠torproject.org 17 Nov '17

17 Nov '17

commit 2cee26b16447c143333ffc16502ecc28b48060cd Merge: b98614f1a 96b69942a Author: Nick Mathewson <nickm(a)torproject.org> Date: Fri Nov 17 09:56:53 2017 -0500 Merge branch 'bug23817_031' into maint-0.3.2 changes/bug23817 | 3 ++ src/or/directory.c | 40 ++++++++++------ src/or/directory.h | 2 + src/or/entrynodes.c | 121 ++++++++++++++++++++++++++++++++++++++++++++----- src/or/entrynodes.h | 33 ++++++++++---- src/or/microdesc.c | 101 +++++++++++++++++++++++++++++++++++++++++ src/or/microdesc.h | 4 ++ src/or/networkstatus.c | 3 ++ 8 files changed, 272 insertions(+), 35 deletions(-) diff --cc src/or/directory.h index d26d83537,571c30a0f..b57b7b544 --- a/src/or/directory.h +++ b/src/or/directory.h @@@ -191,8 -166,10 +191,10 @@@ STATIC char *accept_encoding_header(voi STATIC int allowed_anonymous_connection_compression_method(compress_method_t); STATIC void warn_disallowed_anonymous_compression_method(compress_method_t); -struct response_handler_args_t; - +STATIC int handle_response_fetch_hsdesc_v3(dir_connection_t *conn, + const response_handler_args_t *args); + STATIC int handle_response_fetch_microdesc(dir_connection_t *conn, - const struct response_handler_args_t *args); ++ const response_handler_args_t *args); #endif /* defined(DIRECTORY_PRIVATE) */ diff --cc src/or/entrynodes.h index 9e1e72993,29de627de..49bb3e55c --- a/src/or/entrynodes.h +++ b/src/or/entrynodes.h @@@ -550,6 -557,16 +557,14 @@@ STATIC unsigned entry_guards_note_guard unsigned old_state); STATIC int entry_guard_has_higher_priority(entry_guard_t *a, entry_guard_t *b); STATIC char *getinfo_helper_format_single_entry_guard(const entry_guard_t *e); + -STATIC entry_guard_restriction_t * -guard_create_exit_restriction(const uint8_t *exit_id); ++STATIC entry_guard_restriction_t *guard_create_exit_restriction( ++ const uint8_t *exit_id); + -STATIC entry_guard_restriction_t * -guard_create_dirserver_md_restriction(void); ++STATIC entry_guard_restriction_t *guard_create_dirserver_md_restriction(void); + -STATIC void -entry_guard_restriction_free(entry_guard_restriction_t *rst); ++STATIC void entry_guard_restriction_free(entry_guard_restriction_t *rst); + #endif /* defined(ENTRYNODES_PRIVATE) */ void remove_all_entry_guards_for_guard_selection(guard_selection_t *gs); diff --cc src/or/networkstatus.c index 2660e6a32,36e62020e..f31529733 --- a/src/or/networkstatus.c +++ b/src/or/networkstatus.c @@@ -2009,11 -2037,13 +2009,14 @@@ networkstatus_set_current_consensus(con "consensus network status document (%s UTC). Tor needs an " "accurate clock to work correctly. Please check your time and " "date settings!", dbuf, tbuf); - control_event_general_status(LOG_WARN, - "CLOCK_SKEW MIN_SKEW=%ld SOURCE=CONSENSUS", delta); + 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;

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[tor/maint-0.3.2] Fix a clang unitialized-var warning
by nickm＠torproject.org 17 Nov '17

17 Nov '17

commit 3a5ca47d8f0b97da80199c7787b81c28c9247bb3 Author: Nick Mathewson <nickm(a)torproject.org> Date: Tue Nov 7 19:40:52 2017 -0500 Fix a clang unitialized-var warning --- src/test/test_entrynodes.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/test/test_entrynodes.c b/src/test/test_entrynodes.c index 2aef5cbbf..43cc39488 100644 --- a/src/test/test_entrynodes.c +++ b/src/test/test_entrynodes.c @@ -1729,6 +1729,7 @@ test_entry_guard_select_for_circuit_no_confirmed(void *arg) /* Simpler cases: no gaurds are confirmed yet. */ (void)arg; guard_selection_t *gs = guard_selection_new("default", GS_TYPE_NORMAL); + entry_guard_restriction_t *rst = NULL; /* simple starting configuration */ entry_guards_update_primary(gs); @@ -1810,7 +1811,6 @@ test_entry_guard_select_for_circuit_no_confirmed(void *arg) tt_ptr_op(g2, OP_EQ, g); /* But if we impose a restriction, we don't get the same guard */ - entry_guard_restriction_t *rst; rst = guard_create_exit_restriction((uint8_t*)g->identity); g2 = select_entry_guard_for_circuit(gs, GUARD_USAGE_TRAFFIC, rst, &state); tt_ptr_op(g2, OP_NE, g);

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[tor/release-0.3.2] Introduce new guard restriction and use it to skip outdated dirs.
by nickm＠torproject.org 17 Nov '17

17 Nov '17

commit f61e3090fb2975ad8c2a5e138b87c62428c5f46b Author: George Kadianakis <desnacked(a)riseup.net> Date: Mon Nov 6 19:38:47 2017 +0200 Introduce new guard restriction and use it to skip outdated dirs. --- changes/bug23817 | 3 ++ src/or/directory.c | 4 +-- src/or/entrynodes.c | 95 ++++++++++++++++++++++++++++++++++++++++++++++------- src/or/entrynodes.h | 37 +++++++++++++++------ 4 files changed, 116 insertions(+), 23 deletions(-) diff --git a/changes/bug23817 b/changes/bug23817 new file mode 100644 index 000000000..474094279 --- /dev/null +++ b/changes/bug23817 @@ -0,0 +1,3 @@ + o Minor bugfixes (descriptors): + - Don't try fetching microdescriptors from relays that have failed to + deliver them in the past. Fixes bug 23817; bugfix on 0.3.0.1-alpha. diff --git a/src/or/directory.c b/src/or/directory.c index 129309ae4..aec8ef5bf 100644 --- a/src/or/directory.c +++ b/src/or/directory.c @@ -464,7 +464,7 @@ directory_pick_generic_dirserver(dirinfo_type_t type, int pds_flags, log_warn(LD_BUG, "Called when we have UseBridges set."); if (should_use_directory_guards(options)) { - const node_t *node = guards_choose_dirguard(guard_state_out); + const node_t *node = guards_choose_dirguard(dir_purpose, guard_state_out); if (node) rs = node->rs; } else { @@ -598,7 +598,7 @@ directory_get_from_dirserver,( * sort of dir fetch we'll be doing, so it won't return a bridge * that can't answer our question. */ - const node_t *node = guards_choose_dirguard(&guard_state); + const node_t *node = guards_choose_dirguard(dir_purpose, &guard_state); if (node && node->ri) { /* every bridge has a routerinfo. */ routerinfo_t *ri = node->ri; diff --git a/src/or/entrynodes.c b/src/or/entrynodes.c index 26f53cbfe..f2ca7aac2 100644 --- a/src/or/entrynodes.c +++ b/src/or/entrynodes.c @@ -1460,6 +1460,70 @@ guard_in_node_family(const entry_guard_t *guard, const node_t *node) } } +/* Allocate and return a new exit guard restriction (where exit_id is of + * size DIGEST_LEN) */ +STATIC entry_guard_restriction_t * +guard_create_exit_restriction(const uint8_t *exit_id) +{ + entry_guard_restriction_t *rst = NULL; + rst = tor_malloc_zero(sizeof(entry_guard_restriction_t)); + rst->type = RST_EXIT_NODE; + memcpy(rst->exclude_id, exit_id, DIGEST_LEN); + return rst; +} + +/** Allocate and return an outdated md guard restriction. */ +STATIC entry_guard_restriction_t * +guard_create_dirserver_md_restriction(void) +{ + entry_guard_restriction_t *rst = NULL; + + rst = tor_malloc_zero(sizeof(entry_guard_restriction_t)); + rst->type = RST_OUTDATED_MD_DIRSERVER; + + return rst; +} + +/* Return True if guard obeys the exit restriction rst. */ +static int +guard_obeys_exit_restriction(const entry_guard_t *guard, + const entry_guard_restriction_t *rst) +{ + tor_assert(rst->type == RST_EXIT_NODE); + + // Exclude the exit ID and all of its family. + const node_t *node = node_get_by_id((const char*)rst->exclude_id); + if (node && guard_in_node_family(guard, node)) + return 0; + + return tor_memneq(guard->identity, rst->exclude_id, DIGEST_LEN); +} + +/** Return True if guard should be used as a dirserver for fetching + * microdescriptors. */ +static int +guard_obeys_md_dirserver_restriction(const entry_guard_t *guard) +{ + /* Don't enforce dirserver restrictions for bridges since we might not have + * many of those. Be willing to try them over and over again for now. */ + /* XXX: Improvement might be possible here */ + if (guard->bridge_addr) { + return 1; + } + + /* If this guard is an outdated dirserver, don't use it. */ + if (microdesc_relay_is_outdated_dirserver(guard->identity)) { + log_info(LD_GENERAL, "Skipping %s dirserver: outdated", + hex_str(guard->identity, DIGEST_LEN)); + return 0; + } + + log_debug(LD_GENERAL, "%s dirserver obeys md restrictions", + hex_str(guard->identity, DIGEST_LEN)); + + return 1; +} + /** * Return true iff guard obeys the restrictions defined in rst. * (If rst is NULL, there are no restrictions.) @@ -1472,13 +1536,14 @@ entry_guard_obeys_restriction(const entry_guard_t *guard, if (! rst) return 1; // No restriction? No problem. - // Only one kind of restriction exists right now: excluding an exit - // ID and all of its family. - const node_t *node = node_get_by_id((const char*)rst->exclude_id); - if (node && guard_in_node_family(guard, node)) - return 0; + if (rst->type == RST_EXIT_NODE) { + return guard_obeys_exit_restriction(guard, rst); + } else if (rst->type == RST_OUTDATED_MD_DIRSERVER) { + return guard_obeys_md_dirserver_restriction(guard); + } - return tor_memneq(guard->identity, rst->exclude_id, DIGEST_LEN); + tor_assert_nonfatal_unreached(); + return 0; } /** @@ -2105,7 +2170,7 @@ entry_guard_has_higher_priority(entry_guard_t *a, entry_guard_t *b) } /** Release all storage held in restriction */ -static void +STATIC void entry_guard_restriction_free(entry_guard_restriction_t *rst) { tor_free(rst); @@ -3358,8 +3423,8 @@ guards_choose_guard(cpath_build_state_t *state, /* We're building to a targeted exit node, so that node can't be * chosen as our guard for this circuit. Remember that fact in a * restriction. */ - rst = tor_malloc_zero(sizeof(entry_guard_restriction_t)); - memcpy(rst->exclude_id, exit_id, DIGEST_LEN); + rst = guard_create_exit_restriction(exit_id); + tor_assert(rst); } if (entry_guard_pick_for_circuit(get_guard_selection_info(), GUARD_USAGE_TRAFFIC, @@ -3411,12 +3476,20 @@ remove_all_entry_guards(void) /** Helper: pick a directory guard, with whatever algorithm is used. */ const node_t * -guards_choose_dirguard(circuit_guard_state_t **guard_state_out) +guards_choose_dirguard(uint8_t dir_purpose, + circuit_guard_state_t **guard_state_out) { const node_t *r = NULL; + entry_guard_restriction_t *rst = NULL; + + /* If we are fetching microdescs, don't query outdated dirservers. */ + if (dir_purpose == DIR_PURPOSE_FETCH_MICRODESC) { + rst = guard_create_dirserver_md_restriction(); + } + if (entry_guard_pick_for_circuit(get_guard_selection_info(), GUARD_USAGE_DIRGUARD, - NULL, + rst, &r, guard_state_out) < 0) { tor_assert(r == NULL); diff --git a/src/or/entrynodes.h b/src/or/entrynodes.h index 735c7738b..29de627de 100644 --- a/src/or/entrynodes.h +++ b/src/or/entrynodes.h @@ -272,22 +272,28 @@ struct guard_selection_s { struct entry_guard_handle_t; +/** Types of restrictions we impose when picking guard nodes */ +typedef enum guard_restriction_type_t { + /* Don't pick the same guard node as our exit node (or its family) */ + RST_EXIT_NODE = 0, + /* Don't pick dirguards that have previously shown to be outdated */ + RST_OUTDATED_MD_DIRSERVER = 1 +} guard_restriction_type_t; + /** * A restriction to remember which entry guards are off-limits for a given * circuit. * - * Right now, we only use restrictions to block a single guard and its family - * from being selected; this mechanism is designed to be more extensible in - * the future, however. - * * Note: This mechanism is NOT for recording which guards are never to be * used: only which guards cannot be used on one particular circuit. */ struct entry_guard_restriction_t { - /** - * The guard's RSA identity digest must not equal this; and it must not - * be in the same family as any node with this digest. - */ + /* What type of restriction are we imposing? */ + guard_restriction_type_t type; + + /* In case of restriction type RST_EXIT_NODE, the guard's RSA identity + * digest must not equal this; and it must not be in the same family as any + * node with this digest. */ uint8_t exclude_id[DIGEST_LEN]; }; @@ -316,7 +322,8 @@ struct circuit_guard_state_t { int guards_update_all(void); const node_t *guards_choose_guard(cpath_build_state_t *state, circuit_guard_state_t **guard_state_out); -const node_t *guards_choose_dirguard(circuit_guard_state_t **guard_state_out); +const node_t *guards_choose_dirguard(uint8_t dir_purpose, + circuit_guard_state_t **guard_state_out); #if 1 /* XXXX NM I would prefer that all of this stuff be private to @@ -550,7 +557,17 @@ STATIC unsigned entry_guards_note_guard_success(guard_selection_t *gs, unsigned old_state); STATIC int entry_guard_has_higher_priority(entry_guard_t *a, entry_guard_t *b); STATIC char *getinfo_helper_format_single_entry_guard(const entry_guard_t *e); -#endif + +STATIC entry_guard_restriction_t * +guard_create_exit_restriction(const uint8_t *exit_id); + +STATIC entry_guard_restriction_t * +guard_create_dirserver_md_restriction(void); + +STATIC void +entry_guard_restriction_free(entry_guard_restriction_t *rst); + +#endif /* defined(ENTRYNODES_PRIVATE) */ void remove_all_entry_guards_for_guard_selection(guard_selection_t *gs); void remove_all_entry_guards(void);

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[tor/release-0.3.2] Introduce cache for outdated microdesc dirservers.
by nickm＠torproject.org 17 Nov '17

17 Nov '17

commit 7fc64f02a3057405f9e75d70848afd2e9b95da05 Author: George Kadianakis <desnacked(a)riseup.net> Date: Mon Nov 6 14:48:22 2017 +0200 Introduce cache for outdated microdesc dirservers. We gonna use this cache to avoid dirservers without outdated md info. --- src/or/directory.c | 36 +++++++++++------- src/or/directory.h | 7 +++- src/or/microdesc.c | 101 +++++++++++++++++++++++++++++++++++++++++++++++++ src/or/microdesc.h | 6 ++- src/or/networkstatus.c | 3 ++ 5 files changed, 138 insertions(+), 15 deletions(-) diff --git a/src/or/directory.c b/src/or/directory.c index 9494cf02b..129309ae4 100644 --- a/src/or/directory.c +++ b/src/or/directory.c @@ -117,7 +117,8 @@ static void dir_routerdesc_download_failed(smartlist_t *failed, int was_extrainfo, int was_descriptor_digests); static void dir_microdesc_download_failed(smartlist_t *failed, - int status_code); + int status_code, + const char *dir_id); static int client_likes_consensus(const struct consensus_cache_entry_t *ent, const char *want_url); @@ -2178,8 +2179,6 @@ static int handle_response_fetch_detached_signatures(dir_connection_t *, const response_handler_args_t *); static int handle_response_fetch_desc(dir_connection_t *, const response_handler_args_t *); -static int handle_response_fetch_microdesc(dir_connection_t *, - const response_handler_args_t *); static int handle_response_upload_dir(dir_connection_t *, const response_handler_args_t *); static int handle_response_upload_vote(dir_connection_t *, @@ -2839,7 +2838,7 @@ handle_response_fetch_desc(dir_connection_t *conn, * Handler function: processes a response to a request for a group of * microdescriptors **/ -static int +STATIC int handle_response_fetch_microdesc(dir_connection_t *conn, const response_handler_args_t *args) { @@ -2856,6 +2855,7 @@ handle_response_fetch_microdesc(dir_connection_t *conn, conn->base_.port); tor_assert(conn->requested_resource && !strcmpstart(conn->requested_resource, "d/")); + tor_assert_nonfatal(!tor_mem_is_zero(conn->identity_digest, DIGEST_LEN)); which = smartlist_new(); dir_split_resource_into_fingerprints(conn->requested_resource+2, which, NULL, @@ -2866,7 +2866,7 @@ handle_response_fetch_microdesc(dir_connection_t *conn, "soon.", status_code, escaped(reason), conn->base_.address, (int)conn->base_.port, conn->requested_resource); - dir_microdesc_download_failed(which, status_code); + dir_microdesc_download_failed(which, status_code, conn->identity_digest); SMARTLIST_FOREACH(which, char *, cp, tor_free(cp)); smartlist_free(which); return 0; @@ -2878,7 +2878,7 @@ handle_response_fetch_microdesc(dir_connection_t *conn, now, which); if (smartlist_len(which)) { /* Mark remaining ones as failed. */ - dir_microdesc_download_failed(which, status_code); + dir_microdesc_download_failed(which, status_code, conn->identity_digest); } if (mds && smartlist_len(mds)) { control_event_bootstrap(BOOTSTRAP_STATUS_LOADING_DESCRIPTORS, @@ -5546,13 +5546,14 @@ dir_routerdesc_download_failed(smartlist_t *failed, int status_code, * every 10 or 60 seconds (FOO_DESCRIPTOR_RETRY_INTERVAL) in main.c. */ } -/** Called when a connection to download microdescriptors has failed in whole - * or in part. failed is a list of every microdesc digest we didn't - * get. status_code is the http status code we received. Reschedule the - * microdesc downloads as appropriate. */ +/** Called when a connection to download microdescriptors from relay with + * dir_id has failed in whole or in part. failed is a list + * of every microdesc digest we didn't get. status_code is the http + * status code we received. Reschedule the microdesc downloads as + * appropriate. */ static void dir_microdesc_download_failed(smartlist_t *failed, - int status_code) + int status_code, const char *dir_id) { networkstatus_t *consensus = networkstatus_get_latest_consensus_by_flavor(FLAV_MICRODESC); @@ -5563,17 +5564,26 @@ dir_microdesc_download_failed(smartlist_t *failed, if (! consensus) return; + + /* We failed to fetch a microdescriptor from 'dir_id', note it down + * so that we don't try the same relay next time... */ + microdesc_note_outdated_dirserver(dir_id); + SMARTLIST_FOREACH_BEGIN(failed, const char *, d) { rs = router_get_mutable_consensus_status_by_descriptor_digest(consensus,d); if (!rs) continue; dls = &rs->dl_status; if (dls->n_download_failures >= - get_options()->TestingMicrodescMaxDownloadTries) + get_options()->TestingMicrodescMaxDownloadTries) { continue; - { + } + + { /* Increment the failure count for this md fetch */ char buf[BASE64_DIGEST256_LEN+1]; digest256_to_base64(buf, d); + log_info(LD_DIR, "Failed to download md %s from %s", + buf, hex_str(dir_id, DIGEST_LEN)); download_status_increment_failure(dls, status_code, buf, server, now); } diff --git a/src/or/directory.h b/src/or/directory.h index 14d5ae9ef..571c30a0f 100644 --- a/src/or/directory.h +++ b/src/or/directory.h @@ -166,7 +166,12 @@ STATIC char *accept_encoding_header(void); STATIC int allowed_anonymous_connection_compression_method(compress_method_t); STATIC void warn_disallowed_anonymous_compression_method(compress_method_t); -#endif +struct response_handler_args_t; + +STATIC int handle_response_fetch_microdesc(dir_connection_t *conn, + const struct response_handler_args_t *args); + +#endif /* defined(DIRECTORY_PRIVATE) */ #ifdef TOR_UNIT_TESTS /* Used only by test_dir.c */ diff --git a/src/or/microdesc.c b/src/or/microdesc.c index a4e6b409c..32242d005 100644 --- a/src/or/microdesc.c +++ b/src/or/microdesc.c @@ -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 + * relay_digest (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 relay_digest (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 md into f, with appropriate annotations. * On success, return the total number of bytes written, and set * *annotation_len_out 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 cache whose sha256 digest is diff --git a/src/or/microdesc.h b/src/or/microdesc.h index 943873066..1be12156a 100644 --- a/src/or/microdesc.h +++ b/src/or/microdesc.h @@ -50,5 +50,9 @@ int we_fetch_microdescriptors(const or_options_t *options); int we_fetch_router_descriptors(const or_options_t *options); int we_use_microdescriptors_for_circuits(const or_options_t *options); -#endif +void microdesc_note_outdated_dirserver(const char *relay_digest); +int microdesc_relay_is_outdated_dirserver(const char *relay_digest); +void microdesc_reset_outdated_dirservers_list(void); + +#endif /* !defined(TOR_MICRODESC_H) */ diff --git a/src/or/networkstatus.c b/src/or/networkstatus.c index 997280de5..36e62020e 100644 --- a/src/or/networkstatus.c +++ b/src/or/networkstatus.c @@ -2041,6 +2041,9 @@ networkstatus_set_current_consensus(const char *consensus, "CLOCK_SKEW MIN_SKEW=%ld SOURCE=CONSENSUS", delta); } + /* We got a new consesus. Reset our md fetch fail cache */ + microdesc_reset_outdated_dirservers_list(); + router_dir_info_changed(); result = 0;

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[tor/release-0.3.2] Skip dirserver restrictions in small networks.
by nickm＠torproject.org 17 Nov '17

17 Nov '17

commit c400ffc2e88dab54b070a856717fb0ee6fe096cb Author: George Kadianakis <desnacked(a)riseup.net> Date: Mon Nov 13 22:26:22 2017 +0200 Skip dirserver restrictions in small networks. --- src/or/entrynodes.c | 42 ++++++++++++++++++++++++++++++++++-------- 1 file changed, 34 insertions(+), 8 deletions(-) diff --git a/src/or/entrynodes.c b/src/or/entrynodes.c index f2ca7aac2..1cc24d8d6 100644 --- a/src/or/entrynodes.c +++ b/src/or/entrynodes.c @@ -1472,12 +1472,45 @@ guard_create_exit_restriction(const uint8_t *exit_id) return rst; } -/** Allocate and return an outdated md guard restriction. */ +/** If we have less than these many configured bridges, don't set dirserver + * restrictions because we might blacklist all of them. */ +#define TOO_FEW_BRIDGES_FOR_RESTRICTION 10 + +/** Return true if we should set md dirserver restrictions. We might not want + * to set those if our network is too restricted, since we don't want to + * blacklist all our nodes. */ +static int +should_set_md_dirserver_restriction(void) +{ + const guard_selection_t *gs = get_guard_selection_info(); + + /* Don't set a restriction if we are on a restricted guard selection */ + if (gs->type == GS_TYPE_RESTRICTED) { + return 0; + } + + /* Don't set restriction if we are using bridges and have too few of those */ + if (gs->type == GS_TYPE_BRIDGE && gs->sampled_entry_guards) { + int num_sampled_guards = smartlist_len(gs->sampled_entry_guards); + if (num_sampled_guards < TOO_FEW_BRIDGES_FOR_RESTRICTION) { + return 0; + } + } + + return 1; +} + +/** Allocate and return an outdated md guard restriction. Return NULL if no + * such restriction is needed. */ STATIC entry_guard_restriction_t * guard_create_dirserver_md_restriction(void) { entry_guard_restriction_t *rst = NULL; + if (!should_set_md_dirserver_restriction()) { + return NULL; + } + rst = tor_malloc_zero(sizeof(entry_guard_restriction_t)); rst->type = RST_OUTDATED_MD_DIRSERVER; @@ -1504,13 +1537,6 @@ guard_obeys_exit_restriction(const entry_guard_t *guard, static int guard_obeys_md_dirserver_restriction(const entry_guard_t *guard) { - /* Don't enforce dirserver restrictions for bridges since we might not have - * many of those. Be willing to try them over and over again for now. */ - /* XXX: Improvement might be possible here */ - if (guard->bridge_addr) { - return 1; - } - /* If this guard is an outdated dirserver, don't use it. */ if (microdesc_relay_is_outdated_dirserver(guard->identity)) { log_info(LD_GENERAL, "Skipping %s dirserver: outdated",

1 0

[tor/maint-0.3.2] Merge branch 'bug23817_tests_032' into maint-0.3.2
by nickm＠torproject.org 17 Nov '17

17 Nov '17

commit 9c17a6d28b4acf044f408a0c7211e051e238c797 Merge: 9fbc835f1 3a5ca47d8 Author: Nick Mathewson <nickm(a)torproject.org> Date: Fri Nov 17 09:58:12 2017 -0500 Merge branch 'bug23817_tests_032' into maint-0.3.2 src/or/directory.c | 42 ------------- src/or/directory.h | 42 +++++++++++++ src/test/test_entrynodes.c | 146 +++++++++++++++++++++++++++++++++++++++------ 3 files changed, 171 insertions(+), 59 deletions(-)

1 0

[tor/master] Introduce new guard restriction and use it to skip outdated dirs.
by nickm＠torproject.org 17 Nov '17

17 Nov '17

commit f61e3090fb2975ad8c2a5e138b87c62428c5f46b Author: George Kadianakis <desnacked(a)riseup.net> Date: Mon Nov 6 19:38:47 2017 +0200 Introduce new guard restriction and use it to skip outdated dirs. --- changes/bug23817 | 3 ++ src/or/directory.c | 4 +-- src/or/entrynodes.c | 95 ++++++++++++++++++++++++++++++++++++++++++++++------- src/or/entrynodes.h | 37 +++++++++++++++------ 4 files changed, 116 insertions(+), 23 deletions(-) diff --git a/changes/bug23817 b/changes/bug23817 new file mode 100644 index 000000000..474094279 --- /dev/null +++ b/changes/bug23817 @@ -0,0 +1,3 @@ + o Minor bugfixes (descriptors): + - Don't try fetching microdescriptors from relays that have failed to + deliver them in the past. Fixes bug 23817; bugfix on 0.3.0.1-alpha. diff --git a/src/or/directory.c b/src/or/directory.c index 129309ae4..aec8ef5bf 100644 --- a/src/or/directory.c +++ b/src/or/directory.c @@ -464,7 +464,7 @@ directory_pick_generic_dirserver(dirinfo_type_t type, int pds_flags, log_warn(LD_BUG, "Called when we have UseBridges set."); if (should_use_directory_guards(options)) { - const node_t *node = guards_choose_dirguard(guard_state_out); + const node_t *node = guards_choose_dirguard(dir_purpose, guard_state_out); if (node) rs = node->rs; } else { @@ -598,7 +598,7 @@ directory_get_from_dirserver,( * sort of dir fetch we'll be doing, so it won't return a bridge * that can't answer our question. */ - const node_t *node = guards_choose_dirguard(&guard_state); + const node_t *node = guards_choose_dirguard(dir_purpose, &guard_state); if (node && node->ri) { /* every bridge has a routerinfo. */ routerinfo_t *ri = node->ri; diff --git a/src/or/entrynodes.c b/src/or/entrynodes.c index 26f53cbfe..f2ca7aac2 100644 --- a/src/or/entrynodes.c +++ b/src/or/entrynodes.c @@ -1460,6 +1460,70 @@ guard_in_node_family(const entry_guard_t *guard, const node_t *node) } } +/* Allocate and return a new exit guard restriction (where exit_id is of + * size DIGEST_LEN) */ +STATIC entry_guard_restriction_t * +guard_create_exit_restriction(const uint8_t *exit_id) +{ + entry_guard_restriction_t *rst = NULL; + rst = tor_malloc_zero(sizeof(entry_guard_restriction_t)); + rst->type = RST_EXIT_NODE; + memcpy(rst->exclude_id, exit_id, DIGEST_LEN); + return rst; +} + +/** Allocate and return an outdated md guard restriction. */ +STATIC entry_guard_restriction_t * +guard_create_dirserver_md_restriction(void) +{ + entry_guard_restriction_t *rst = NULL; + + rst = tor_malloc_zero(sizeof(entry_guard_restriction_t)); + rst->type = RST_OUTDATED_MD_DIRSERVER; + + return rst; +} + +/* Return True if guard obeys the exit restriction rst. */ +static int +guard_obeys_exit_restriction(const entry_guard_t *guard, + const entry_guard_restriction_t *rst) +{ + tor_assert(rst->type == RST_EXIT_NODE); + + // Exclude the exit ID and all of its family. + const node_t *node = node_get_by_id((const char*)rst->exclude_id); + if (node && guard_in_node_family(guard, node)) + return 0; + + return tor_memneq(guard->identity, rst->exclude_id, DIGEST_LEN); +} + +/** Return True if guard should be used as a dirserver for fetching + * microdescriptors. */ +static int +guard_obeys_md_dirserver_restriction(const entry_guard_t *guard) +{ + /* Don't enforce dirserver restrictions for bridges since we might not have + * many of those. Be willing to try them over and over again for now. */ + /* XXX: Improvement might be possible here */ + if (guard->bridge_addr) { + return 1; + } + + /* If this guard is an outdated dirserver, don't use it. */ + if (microdesc_relay_is_outdated_dirserver(guard->identity)) { + log_info(LD_GENERAL, "Skipping %s dirserver: outdated", + hex_str(guard->identity, DIGEST_LEN)); + return 0; + } + + log_debug(LD_GENERAL, "%s dirserver obeys md restrictions", + hex_str(guard->identity, DIGEST_LEN)); + + return 1; +} + /** * Return true iff guard obeys the restrictions defined in rst. * (If rst is NULL, there are no restrictions.) @@ -1472,13 +1536,14 @@ entry_guard_obeys_restriction(const entry_guard_t *guard, if (! rst) return 1; // No restriction? No problem. - // Only one kind of restriction exists right now: excluding an exit - // ID and all of its family. - const node_t *node = node_get_by_id((const char*)rst->exclude_id); - if (node && guard_in_node_family(guard, node)) - return 0; + if (rst->type == RST_EXIT_NODE) { + return guard_obeys_exit_restriction(guard, rst); + } else if (rst->type == RST_OUTDATED_MD_DIRSERVER) { + return guard_obeys_md_dirserver_restriction(guard); + } - return tor_memneq(guard->identity, rst->exclude_id, DIGEST_LEN); + tor_assert_nonfatal_unreached(); + return 0; } /** @@ -2105,7 +2170,7 @@ entry_guard_has_higher_priority(entry_guard_t *a, entry_guard_t *b) } /** Release all storage held in restriction */ -static void +STATIC void entry_guard_restriction_free(entry_guard_restriction_t *rst) { tor_free(rst); @@ -3358,8 +3423,8 @@ guards_choose_guard(cpath_build_state_t *state, /* We're building to a targeted exit node, so that node can't be * chosen as our guard for this circuit. Remember that fact in a * restriction. */ - rst = tor_malloc_zero(sizeof(entry_guard_restriction_t)); - memcpy(rst->exclude_id, exit_id, DIGEST_LEN); + rst = guard_create_exit_restriction(exit_id); + tor_assert(rst); } if (entry_guard_pick_for_circuit(get_guard_selection_info(), GUARD_USAGE_TRAFFIC, @@ -3411,12 +3476,20 @@ remove_all_entry_guards(void) /** Helper: pick a directory guard, with whatever algorithm is used. */ const node_t * -guards_choose_dirguard(circuit_guard_state_t **guard_state_out) +guards_choose_dirguard(uint8_t dir_purpose, + circuit_guard_state_t **guard_state_out) { const node_t *r = NULL; + entry_guard_restriction_t *rst = NULL; + + /* If we are fetching microdescs, don't query outdated dirservers. */ + if (dir_purpose == DIR_PURPOSE_FETCH_MICRODESC) { + rst = guard_create_dirserver_md_restriction(); + } + if (entry_guard_pick_for_circuit(get_guard_selection_info(), GUARD_USAGE_DIRGUARD, - NULL, + rst, &r, guard_state_out) < 0) { tor_assert(r == NULL); diff --git a/src/or/entrynodes.h b/src/or/entrynodes.h index 735c7738b..29de627de 100644 --- a/src/or/entrynodes.h +++ b/src/or/entrynodes.h @@ -272,22 +272,28 @@ struct guard_selection_s { struct entry_guard_handle_t; +/** Types of restrictions we impose when picking guard nodes */ +typedef enum guard_restriction_type_t { + /* Don't pick the same guard node as our exit node (or its family) */ + RST_EXIT_NODE = 0, + /* Don't pick dirguards that have previously shown to be outdated */ + RST_OUTDATED_MD_DIRSERVER = 1 +} guard_restriction_type_t; + /** * A restriction to remember which entry guards are off-limits for a given * circuit. * - * Right now, we only use restrictions to block a single guard and its family - * from being selected; this mechanism is designed to be more extensible in - * the future, however. - * * Note: This mechanism is NOT for recording which guards are never to be * used: only which guards cannot be used on one particular circuit. */ struct entry_guard_restriction_t { - /** - * The guard's RSA identity digest must not equal this; and it must not - * be in the same family as any node with this digest. - */ + /* What type of restriction are we imposing? */ + guard_restriction_type_t type; + + /* In case of restriction type RST_EXIT_NODE, the guard's RSA identity + * digest must not equal this; and it must not be in the same family as any + * node with this digest. */ uint8_t exclude_id[DIGEST_LEN]; }; @@ -316,7 +322,8 @@ struct circuit_guard_state_t { int guards_update_all(void); const node_t *guards_choose_guard(cpath_build_state_t *state, circuit_guard_state_t **guard_state_out); -const node_t *guards_choose_dirguard(circuit_guard_state_t **guard_state_out); +const node_t *guards_choose_dirguard(uint8_t dir_purpose, + circuit_guard_state_t **guard_state_out); #if 1 /* XXXX NM I would prefer that all of this stuff be private to @@ -550,7 +557,17 @@ STATIC unsigned entry_guards_note_guard_success(guard_selection_t *gs, unsigned old_state); STATIC int entry_guard_has_higher_priority(entry_guard_t *a, entry_guard_t *b); STATIC char *getinfo_helper_format_single_entry_guard(const entry_guard_t *e); -#endif + +STATIC entry_guard_restriction_t * +guard_create_exit_restriction(const uint8_t *exit_id); + +STATIC entry_guard_restriction_t * +guard_create_dirserver_md_restriction(void); + +STATIC void +entry_guard_restriction_free(entry_guard_restriction_t *rst); + +#endif /* defined(ENTRYNODES_PRIVATE) */ void remove_all_entry_guards_for_guard_selection(guard_selection_t *gs); void remove_all_entry_guards(void);

1 0

[tor/master] Fix a wide comment
by nickm＠torproject.org 17 Nov '17

17 Nov '17

commit 9fbc835f10e9fba6a9b0c6643a41aee9c8aa05c2 Author: Nick Mathewson <nickm(a)torproject.org> Date: Fri Nov 17 09:57:15 2017 -0500 Fix a wide comment --- src/or/scheduler.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/src/or/scheduler.c b/src/or/scheduler.c index dabac386d..cbf51447b 100644 --- a/src/or/scheduler.c +++ b/src/or/scheduler.c @@ -258,9 +258,10 @@ select_scheduler(void) /* We should only log this once in most cases. If it was the kernel * losing support for kist that caused scheduler_can_use_kist() to * return false, then this flag makes sure we only log this message - * once. If it was the consensus that switched from "yes use kist" to - * "no don't use kist", then we still set the flag so we log once, but - * we unset the flag elsewhere if we ever can_use_kist() again. + * once. If it was the consensus that switched from "yes use kist" + * to "no don't use kist", then we still set the flag so we log + * once, but we unset the flag elsewhere if we ever can_use_kist() + * again. */ have_logged_kist_suddenly_disabled = 1; log_notice(LD_SCHED, "Scheduler type KIST has been disabled by "

1 0

[tor/master] Fix a clang unitialized-var warning
by nickm＠torproject.org 17 Nov '17

17 Nov '17

commit 3a5ca47d8f0b97da80199c7787b81c28c9247bb3 Author: Nick Mathewson <nickm(a)torproject.org> Date: Tue Nov 7 19:40:52 2017 -0500 Fix a clang unitialized-var warning --- src/test/test_entrynodes.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/test/test_entrynodes.c b/src/test/test_entrynodes.c index 2aef5cbbf..43cc39488 100644 --- a/src/test/test_entrynodes.c +++ b/src/test/test_entrynodes.c @@ -1729,6 +1729,7 @@ test_entry_guard_select_for_circuit_no_confirmed(void *arg) /* Simpler cases: no gaurds are confirmed yet. */ (void)arg; guard_selection_t *gs = guard_selection_new("default", GS_TYPE_NORMAL); + entry_guard_restriction_t *rst = NULL; /* simple starting configuration */ entry_guards_update_primary(gs); @@ -1810,7 +1811,6 @@ test_entry_guard_select_for_circuit_no_confirmed(void *arg) tt_ptr_op(g2, OP_EQ, g); /* But if we impose a restriction, we don't get the same guard */ - entry_guard_restriction_t *rst; rst = guard_create_exit_restriction((uint8_t*)g->identity); g2 = select_entry_guard_for_circuit(gs, GUARD_USAGE_TRAFFIC, rst, &state); tt_ptr_op(g2, OP_NE, g);

1 0