make L2 vanguards actually independent

We had omitted some checks for whether our vanguards (second layer
guards from proposal 333) overlapped or came from the same family.
Now make sure to pick each of them to be independent.

Fixes bug 40639; bugfix on 0.4.7.1-alpha.
This commit is contained in:
Roger Dingledine 2022-07-07 01:16:53 -04:00
parent b2665ad639
commit 7b1fffe0dd
2 changed files with 14 additions and 1 deletions

5
changes/bug40639 Normal file
View File

@ -0,0 +1,5 @@
o Major bugfixes (vanguards):
- We had omitted some checks for whether our vanguards (second layer
guards from proposal 333) overlapped or came from the same family.
Now make sure to pick each of them to be independent. Fixes bug
40639; bugfix on 0.4.7.1-alpha.

View File

@ -4136,8 +4136,16 @@ maintain_layer2_guards(void)
log_info(LD_GENERAL, "Adding %d guards to Layer2 routerset",
new_guards_needed_n);
/* Add required guards to the list */
/* First gather the exclusions based on our current L2 guards */
smartlist_t *excluded = smartlist_new();
SMARTLIST_FOREACH_BEGIN(layer2_guards, layer2_guard_t *, g) {
/* Exclude existing L2 guard + family so that we don't double-pick. */
const node_t *existing = node_get_by_id(g->identity);
if (existing)
nodelist_add_node_and_family(excluded, existing);
} SMARTLIST_FOREACH_END(g);
/* Add required guards to the list */
for (int i = 0; i < new_guards_needed_n; i++) {
const node_t *choice = NULL;
const or_options_t *options = get_options();