replace L2 vanguards that aren't Fast or Stable

Rotate to a new L2 vanguard whenever an existing one loses the
Stable or Fast flag. Previously, we would leave these relays in the
L2 vanguard list but never use them, and if all of our vanguards
end up like this we wouldn't have any middle nodes left to choose
from so we would fail to make onion-related circuits.

Fixes bug 40805; bugfix on 0.4.7.1-alpha.
This commit is contained in:
Roger Dingledine 2023-07-05 18:39:57 -04:00
parent d60fab8c9e
commit 3335829347
2 changed files with 12 additions and 2 deletions

7
changes/bug40805 Normal file
View File

@ -0,0 +1,7 @@
o Major bugfixes (vanguards):
- Rotate to a new L2 vanguard whenever an existing one loses the
Stable or Fast flag. Previously, we would leave these relays in the
L2 vanguard list but never use them, and if all of our vanguards
end up like this we wouldn't have any middle nodes left to choose
from so we would fail to make onion-related circuits. Fixes bug
40805; bugfix on 0.4.7.1-alpha.

View File

@ -150,6 +150,7 @@
#include "feature/nodelist/node_st.h"
#include "core/or/origin_circuit_st.h"
#include "app/config/or_state_st.h"
#include "src/feature/nodelist/routerstatus_st.h"
/** A list of existing guard selection contexts. */
static smartlist_t *guard_contexts = NULL;
@ -4115,8 +4116,10 @@ maintain_layer2_guards(void)
}
/* Expire if relay has left consensus */
if (router_get_consensus_status_by_id(g->identity) == NULL) {
log_info(LD_GENERAL, "Removing missing Layer2 guard %s",
const routerstatus_t *rs = router_get_consensus_status_by_id(g->identity);
if (rs == NULL || !rs->is_stable || !rs->is_fast) {
log_info(LD_GENERAL, "Removing %s Layer2 guard %s",
rs ? "unsuitable" : "missing",
safe_str_client(hex_str(g->identity, DIGEST_LEN)));
// Nickname may be gone from consensus and doesn't matter anyway
control_event_guard("None", g->identity, "BAD_L2");