commit 7a45bc74a430ff64f0696c77f075f9c830822413 Author: teor <teor@torproject.org> Date: Thu Nov 29 00:46:39 2018 +1000 Dir: when Tor's clock is behind, use a future consensus to bootstrap When Tor's clock is behind the clocks on the authorities, allow Tor to bootstrap successfully. Fixes bug 28591; bugfix on 0.2.0.9-alpha. --- changes/bug28591 | 4 ++++ src/feature/nodelist/microdesc.c | 10 ++++++---- src/feature/nodelist/networkstatus.c | 35 ++++++++++++++++++++++++----------- src/feature/nodelist/networkstatus.h | 2 ++ src/test/test_entrynodes.c | 32 ++++++++++++++++++++++---------- src/test/test_routerlist.c | 1 - 6 files changed, 58 insertions(+), 26 deletions(-) diff --git a/changes/bug28591 b/changes/bug28591 new file mode 100644 index 000000000..3a1c96ac1 --- /dev/null +++ b/changes/bug28591 @@ -0,0 +1,4 @@ + o Minor bugfixes (client, bootstrap): + - When Tor's clock is behind the clocks on the authorities, allow Tor to + bootstrap successfully. Fixes bug 28591; bugfix on 0.2.0.9-alpha. + diff --git a/src/feature/nodelist/microdesc.c b/src/feature/nodelist/microdesc.c index 3f5085412..8c5a9ee61 100644 --- a/src/feature/nodelist/microdesc.c +++ b/src/feature/nodelist/microdesc.c @@ -110,8 +110,9 @@ microdesc_note_outdated_dirserver(const char *relay_digest) /* If we have a reasonably live consensus, then most of our dirservers should * still be caching all the microdescriptors in it. Reasonably live - * consensuses are up to a day old. But microdescriptors expire 7 days after - * the last consensus that referenced them. */ + * consensuses are up to a day old (or a day in the future). But + * microdescriptors expire 7 days after the last consensus that referenced + * them. */ if (!networkstatus_get_reasonably_live_consensus(approx_time(), FLAV_MICRODESC)) { return; @@ -544,8 +545,8 @@ microdesc_cache_clean(microdesc_cache_t *cache, time_t cutoff, int force) size_t bytes_dropped = 0; time_t now = time(NULL); - /* If we don't know a live consensus, don't believe last_listed values: we - * might be starting up after being down for a while. */ + /* If we don't know a reasonably live consensus, don't believe last_listed + * values: we might be starting up after being down for a while. */ if (! force && ! networkstatus_get_reasonably_live_consensus(now, FLAV_MICRODESC)) return; @@ -973,6 +974,7 @@ update_microdesc_downloads(time_t now) if (directory_too_idle_to_fetch_descriptors(options, now)) return; + /* Give up if we don't have a reasonably live consensus. */ consensus = networkstatus_get_reasonably_live_consensus(now, FLAV_MICRODESC); if (!consensus) return; diff --git a/src/feature/nodelist/networkstatus.c b/src/feature/nodelist/networkstatus.c index 51e720a98..a40c3dfb2 100644 --- a/src/feature/nodelist/networkstatus.c +++ b/src/feature/nodelist/networkstatus.c @@ -1377,7 +1377,7 @@ networkstatus_get_dl_status_by_flavor_running,(consensus_flavor_t flavor)) } /** Return the most recent consensus that we have downloaded, or NULL if we - * don't have one. */ + * don't have one. May return future or expired consensuses. */ MOCK_IMPL(networkstatus_t *, networkstatus_get_latest_consensus,(void)) { @@ -1388,7 +1388,7 @@ networkstatus_get_latest_consensus,(void)) } /** Return the latest consensus we have whose flavor matches <b>f</b>, or NULL - * if we don't have one. */ + * if we don't have one. May return future or expired consensuses. */ MOCK_IMPL(networkstatus_t *, networkstatus_get_latest_consensus_by_flavor,(consensus_flavor_t f)) { @@ -1422,10 +1422,11 @@ networkstatus_is_live(const networkstatus_t *ns, time_t now) return (ns->valid_after <= now && now <= ns->valid_until); } -/** Determine if <b>consensus</b> is valid or expired recently enough that - * we can still use it. +/** Determine if <b>consensus</b> is valid, or expired recently enough, or not + * too far in the future, so that we can still use it. * - * Return 1 if the consensus is reasonably live, or 0 if it is too old. + * Return 1 if the consensus is reasonably live, or 0 if it is too old or + * too new. */ int networkstatus_consensus_reasonably_live(const networkstatus_t *consensus, @@ -1434,29 +1435,42 @@ networkstatus_consensus_reasonably_live(const networkstatus_t *consensus, if (BUG(!consensus)) return 0; - return networkstatus_valid_until_is_reasonably_live(consensus->valid_until, + return networkstatus_valid_after_is_reasonably_live(consensus->valid_after, + now) && + networkstatus_valid_until_is_reasonably_live(consensus->valid_until, now); } +#define REASONABLY_LIVE_TIME (24*60*60) + +/** As networkstatus_consensus_reasonably_live, but takes a valid_after + * time, and checks to see if it is in the past, or not too far in the future. + */ +int +networkstatus_valid_after_is_reasonably_live(time_t valid_after, + time_t now) +{ + return (now >= valid_after - REASONABLY_LIVE_TIME); +} + /** As networkstatus_consensus_reasonably_live, but takes a valid_until - * time rather than an entire consensus. */ + * time, and checks to see if it is in the future, or not too far in the past. + */ 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); } /** As networkstatus_get_live_consensus(), but is way more tolerant of expired - * consensuses. */ + * and future consensuses. */ MOCK_IMPL(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 @@ -2082,7 +2096,6 @@ networkstatus_set_current_consensus(const char *consensus, nodelist_set_consensus(c); - /* XXXXNM Microdescs: needs a non-ns variant. ???? NM*/ update_consensus_networkstatus_fetch_time(now); /* Change the cell EWMA settings */ diff --git a/src/feature/nodelist/networkstatus.h b/src/feature/nodelist/networkstatus.h index 7b1a0ff72..6f1d15d53 100644 --- a/src/feature/nodelist/networkstatus.h +++ b/src/feature/nodelist/networkstatus.h @@ -87,6 +87,8 @@ MOCK_DECL(networkstatus_t *, networkstatus_get_live_consensus,(time_t now)); int networkstatus_is_live(const networkstatus_t *ns, time_t now); int networkstatus_consensus_reasonably_live(const networkstatus_t *consensus, time_t now); +int networkstatus_valid_after_is_reasonably_live(time_t valid_after, + time_t now); int networkstatus_valid_until_is_reasonably_live(time_t valid_until, time_t now); MOCK_DECL(networkstatus_t *,networkstatus_get_reasonably_live_consensus, diff --git a/src/test/test_entrynodes.c b/src/test/test_entrynodes.c index 52b87a84a..348c642a2 100644 --- a/src/test/test_entrynodes.c +++ b/src/test/test_entrynodes.c @@ -127,6 +127,9 @@ big_fake_network_cleanup(const struct testcase_t *testcase, void *ptr) return 1; /* NOP */ } +#define REASONABLY_FUTURE " reasonably-future" +#define REASONABLY_PAST " reasonably-past" + /* Unittest setup function: Setup a fake network. */ static void * big_fake_network_setup(const struct testcase_t *testcase) @@ -138,9 +141,10 @@ big_fake_network_setup(const struct testcase_t *testcase) const int N_NODES = 271; const char *argument = testcase->setup_data; - int reasonably_live_consensus = 0; + int reasonably_future_consensus = 0, reasonably_past_consensus = 0; if (argument) { - reasonably_live_consensus = strstr(argument, "reasonably-live") != NULL; + reasonably_future_consensus = strstr(argument, REASONABLY_FUTURE) != NULL; + reasonably_past_consensus = strstr(argument, REASONABLY_PAST) != NULL; } big_fake_net_nodes = smartlist_new(); @@ -198,11 +202,15 @@ big_fake_network_setup(const struct testcase_t *testcase) dummy_state = tor_malloc_zero(sizeof(or_state_t)); dummy_consensus = tor_malloc_zero(sizeof(networkstatus_t)); - if (reasonably_live_consensus) { - /* Make the dummy consensus valid from 4 hours ago, but expired an hour + if (reasonably_future_consensus) { + /* Make the dummy consensus valid in 6 hours, and expiring in 7 hours. */ + dummy_consensus->valid_after = approx_time() + 6*3600; + dummy_consensus->valid_until = approx_time() + 7*3600; + } else if (reasonably_past_consensus) { + /* Make the dummy consensus valid from 16 hours ago, but expired 12 hours * ago. */ - dummy_consensus->valid_after = approx_time() - 4*3600; - dummy_consensus->valid_until = approx_time() - 3600; + dummy_consensus->valid_after = approx_time() - 16*3600; + dummy_consensus->valid_until = approx_time() - 12*3600; } else { /* Make the dummy consensus valid for an hour either side of now. */ dummy_consensus->valid_after = approx_time() - 3600; @@ -3035,13 +3043,17 @@ static const struct testcase_setup_t upgrade_circuits = { #define BFN_TEST(name) \ EN_TEST_BASE(name, TT_FORK, &big_fake_network, NULL), \ - { #name "_reasonably_live", test_entry_guard_ ## name, TT_FORK, \ - &big_fake_network, (void*)("reasonably-live") } + { #name "_reasonably_future", test_entry_guard_ ## name, TT_FORK, \ + &big_fake_network, (void*)(REASONABLY_FUTURE) }, \ + { #name "_reasonably_past", test_entry_guard_ ## name, TT_FORK, \ + &big_fake_network, (void*)(REASONABLY_PAST) } #define UPGRADE_TEST(name, arg) \ EN_TEST_BASE(name, TT_FORK, &upgrade_circuits, arg), \ - { #name "_reasonably_live", test_entry_guard_ ## name, TT_FORK, \ - &upgrade_circuits, (void*)(arg " reasonably-live") } + { #name "_reasonably_future", test_entry_guard_ ## name, TT_FORK, \ + &upgrade_circuits, (void*)(arg REASONABLY_FUTURE) }, \ + { #name "_reasonably_past", test_entry_guard_ ## name, TT_FORK, \ + &upgrade_circuits, (void*)(arg REASONABLY_PAST) } struct testcase_t entrynodes_tests[] = { NO_PREFIX_TEST(node_preferred_orport), diff --git a/src/test/test_routerlist.c b/src/test/test_routerlist.c index 67af2fd48..6ba4877b9 100644 --- a/src/test/test_routerlist.c +++ b/src/test/test_routerlist.c @@ -301,7 +301,6 @@ test_router_pick_directory_server_impl(void *arg) tt_assert(!networkstatus_consensus_is_bootstrapping(con_md->valid_until + 24*60*60)); /* These times are outside the test validity period */ - tt_assert(networkstatus_consensus_is_bootstrapping(now)); tt_assert(networkstatus_consensus_is_bootstrapping(now + 2*24*60*60)); tt_assert(networkstatus_consensus_is_bootstrapping(now - 2*24*60*60));