diff --git a/changes/bug22400_01 b/changes/bug22400_01 new file mode 100644 index 000000000..454c5f746 --- /dev/null +++ b/changes/bug22400_01 @@ -0,0 +1,4 @@ + o Major bugfixes (entry guards): + - When starting with an old consensus, do not add new entry guards + unless the consensus is "reasonably live" (under 1 day old). Fixes + one root cause of bug 22400; bugfix on 0.3.0.1-alpha. diff --git a/src/or/entrynodes.c b/src/or/entrynodes.c index 5b5e13bce..aba35e69f 100644 --- a/src/or/entrynodes.c +++ b/src/or/entrynodes.c @@ -1093,6 +1093,18 @@ select_and_add_guard_item_for_sample(guard_selection_t *gs, return added_guard; } +/** Return true iff we need a consensus to maintain our */ +static int +live_consensus_is_missing(const guard_selection_t *gs) +{ + tor_assert(gs); + if (gs->type == GS_TYPE_BRIDGE) { + /* We don't update bridges from the consensus; they aren't there. */ + return 0; + } + return networkstatus_get_live_consensus(approx_time()) == NULL; +} + /** * Add new guards to the sampled guards in gs until there are * enough usable filtered guards, but never grow the sample beyond its @@ -1104,6 +1116,13 @@ entry_guards_expand_sample(guard_selection_t *gs) { tor_assert(gs); const or_options_t *options = get_options(); + + if (live_consensus_is_missing(gs)) { + log_info(LD_GUARD, "Not expanding the sample guard set; we have " + "no live consensus."); + return NULL; + } + int n_sampled = smartlist_len(gs->sampled_entry_guards); entry_guard_t *added_guard = NULL; int n_usable_filtered_guards = num_reachable_filtered_guards(gs, NULL); @@ -1212,18 +1231,13 @@ sampled_guards_update_from_consensus(guard_selection_t *gs) // It's important to use only a live consensus here; we don't want to // make changes based on anything expired or old. - if (gs->type != GS_TYPE_BRIDGE) { - networkstatus_t *ns = networkstatus_get_live_consensus(approx_time()); - - if (! ns) { - log_info(LD_GUARD, "No live consensus; can't update " - "sampled entry guards."); - return; - } else { - log_info(LD_GUARD, "Updating sampled guard status based on received " - "consensus."); - } + if (live_consensus_is_missing(gs)) { + log_info(LD_GUARD, "Not updating the sample guard set; we have " + "no live consensus."); + return; } + log_info(LD_GUARD, "Updating sampled guard status based on received " + "consensus."); int n_changes = 0;