Don't expand guard sample set unless consensus is "reasonably live"

Fixes what I think is the main root cause of 22400. Bugfix on
0.3.0.1-alpha.
This commit is contained in:
Nick Mathewson 2017-06-19 15:48:47 -04:00
parent 71c701927a
commit 32e486de97
2 changed files with 19 additions and 0 deletions

4
changes/bug22400_01 Normal file
View File

@ -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.

View File

@ -1104,6 +1104,21 @@ entry_guards_expand_sample(guard_selection_t *gs)
{
tor_assert(gs);
const or_options_t *options = get_options();
if (gs->type != GS_TYPE_BRIDGE) {
networkstatus_t *consensus = networkstatus_get_latest_consensus();
time_t now = approx_time();
if (consensus == NULL) {
log_info(LD_GUARD, "Not expanding the sample guard set; we have "
"no consensus.");
return NULL;
} else if (!networkstatus_consensus_reasonably_live(consensus, now)) {
log_info(LD_GUARD, "Not expanding the sample guard set; we have "
"a consensus, but it is far too old.");
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);