diff options
| -rw-r--r-- | changes/bug24977 | 5 | ||||
| -rw-r--r-- | src/or/hs_common.c | 17 | ||||
| -rw-r--r-- | src/or/nodelist.c | 30 | ||||
| -rw-r--r-- | src/or/nodelist.h | 1 | ||||
| -rw-r--r-- | src/or/voting_schedule.c | 26 | ||||
| -rw-r--r-- | src/or/voting_schedule.h | 4 |
6 files changed, 76 insertions, 7 deletions
diff --git a/changes/bug24977 b/changes/bug24977 new file mode 100644 index 0000000000..f8127a2a73 --- /dev/null +++ b/changes/bug24977 @@ -0,0 +1,5 @@ + o Minor bugfixes (onion services): + - Recompute some consensus information after clock skews or when we + transition from a non-live consensus to a live consensus. We do this to + avoid having an outdated state which could impact next-generation onion + services. Fixes bug 24977; bugfix on 0.3.2.1-alpha. diff --git a/src/or/hs_common.c b/src/or/hs_common.c index c63d4330d6..4ee06dd9b6 100644 --- a/src/or/hs_common.c +++ b/src/or/hs_common.c @@ -1338,15 +1338,20 @@ hs_get_responsible_hsdirs(const ed25519_public_key_t *blinded_pk, sorted_nodes = smartlist_new(); + /* Make sure we actually have a live consensus */ + networkstatus_t *c = networkstatus_get_live_consensus(approx_time()); + if (!c || smartlist_len(c->routerstatus_list) == 0) { + log_warn(LD_REND, "No live consensus so we can't get the responsible " + "hidden service directories."); + goto done; + } + + /* Ensure the nodelist is fresh, since it contains the HSDir indices. */ + nodelist_ensure_freshness(c); + /* Add every node_t that support HSDir v3 for which we do have a valid * hsdir_index already computed for them for this consensus. */ { - networkstatus_t *c = networkstatus_get_latest_consensus(); - if (!c || smartlist_len(c->routerstatus_list) == 0) { - log_warn(LD_REND, "No valid consensus so we can't get the responsible " - "hidden service directories."); - goto done; - } SMARTLIST_FOREACH_BEGIN(c->routerstatus_list, const routerstatus_t *, rs) { /* Even though this node_t object won't be modified and should be const, * we can't add const object in a smartlist_t. */ diff --git a/src/or/nodelist.c b/src/or/nodelist.c index 5e575e9a83..060f5d908f 100644 --- a/src/or/nodelist.c +++ b/src/or/nodelist.c @@ -121,6 +121,11 @@ typedef struct nodelist_t { /* Set of addresses that belong to nodes we believe in. */ address_set_t *node_addrs; + + /* The valid-after time of the last live consensus that initialized the + * nodelist. We use this to detect outdated nodelists that need to be + * rebuilt using a newer consensus. */ + time_t live_consensus_valid_after; } nodelist_t; static inline unsigned int @@ -638,6 +643,12 @@ nodelist_set_consensus(networkstatus_t *ns) } } SMARTLIST_FOREACH_END(node); } + + /* If the consensus is live, note down the consensus valid-after that formed + * the nodelist. */ + if (networkstatus_is_live(ns, approx_time())) { + the_nodelist->live_consensus_valid_after = ns->valid_after; + } } /** Return 1 iff <b>node</b> has Exit flag and no BadExit flag. @@ -871,6 +882,25 @@ nodelist_assert_ok(void) digestmap_free(dm, NULL); } +/** Ensure that the nodelist has been created with the most recent consensus. + * If that's not the case, make it so. */ +void +nodelist_ensure_freshness(networkstatus_t *ns) +{ + tor_assert(ns); + + /* We don't even have a nodelist: this is a NOP. */ + if (!the_nodelist) { + return; + } + + if (the_nodelist->live_consensus_valid_after != ns->valid_after) { + log_info(LD_GENERAL, "Nodelist was not fresh: rebuilding. (%d / %d)", + (int) the_nodelist->live_consensus_valid_after, + (int) ns->valid_after); + nodelist_set_consensus(ns); + } +} /** Return a list of a node_t * for every node we know about. The caller * MUST NOT modify the list. (You can set and clear flags in the nodes if * you must, but you must not add or remove nodes.) */ diff --git a/src/or/nodelist.h b/src/or/nodelist.h index fd91a26832..b5614d957f 100644 --- a/src/or/nodelist.h +++ b/src/or/nodelist.h @@ -29,6 +29,7 @@ const node_t *node_get_by_hex_id(const char *identity_digest, node_t *nodelist_set_routerinfo(routerinfo_t *ri, routerinfo_t **ri_old_out); node_t *nodelist_add_microdesc(microdesc_t *md); void nodelist_set_consensus(networkstatus_t *ns); +void nodelist_ensure_freshness(networkstatus_t *ns); int nodelist_probably_contains_address(const tor_addr_t *addr); void nodelist_remove_microdesc(const char *identity_digest, microdesc_t *md); diff --git a/src/or/voting_schedule.c b/src/or/voting_schedule.c index 983cabbbf3..9d2ebd0385 100644 --- a/src/or/voting_schedule.c +++ b/src/or/voting_schedule.c @@ -85,6 +85,10 @@ get_voting_schedule(const or_options_t *options, time_t now, int severity) interval = (int)( consensus->fresh_until - consensus->valid_after ); vote_delay = consensus->vote_seconds; dist_delay = consensus->dist_seconds; + + /* Note down the consensus valid after, so that we detect outdated voting + * schedules in case of skewed clocks etc. */ + new_voting_schedule->live_consensus_valid_after = consensus->valid_after; } else { interval = options->TestingV3AuthInitialVotingInterval; vote_delay = options->TestingV3AuthInitialVoteDelay; @@ -140,14 +144,34 @@ voting_schedule_t voting_schedule; time_t voting_schedule_get_next_valid_after_time(void) { + time_t now = approx_time(); + bool need_to_recalculate_voting_schedule = false; + /* This is a safe guard in order to make sure that the voting schedule * static object is at least initialized. Using this function with a zeroed * voting schedule can lead to bugs. */ if (tor_mem_is_zero((const char *) &voting_schedule, sizeof(voting_schedule))) { - voting_schedule_recalculate_timing(get_options(), time(NULL)); + need_to_recalculate_voting_schedule = true; + goto done; /* no need for next check if we have to recalculate anyway */ + } + + /* Also make sure we are not using an outdated voting schedule. If we have a + * newer consensus, make sure we recalculate the voting schedule. */ + const networkstatus_t *ns = networkstatus_get_live_consensus(now); + if (ns && ns->valid_after != voting_schedule.live_consensus_valid_after) { + log_info(LD_DIR, "Voting schedule is outdated: recalculating (%d/%d)", + (int) ns->valid_after, + (int) voting_schedule.live_consensus_valid_after); + need_to_recalculate_voting_schedule = true; + } + + done: + if (need_to_recalculate_voting_schedule) { + voting_schedule_recalculate_timing(get_options(), now); voting_schedule.created_on_demand = 1; } + return voting_schedule.interval_starts; } diff --git a/src/or/voting_schedule.h b/src/or/voting_schedule.h index 4f9d584031..087701408e 100644 --- a/src/or/voting_schedule.h +++ b/src/or/voting_schedule.h @@ -43,6 +43,10 @@ typedef struct { * timings only for the first vote even though this object was initilized * prior to voting. */ int created_on_demand; + + /** The valid-after time of the last live consensus that filled this voting + * schedule. It's used to detect outdated voting schedules. */ + time_t live_consensus_valid_after; } voting_schedule_t; /* Public API. */ |