commit c400ffc2e88dab54b070a856717fb0ee6fe096cb Author: George Kadianakis <desnacked@riseup.net> Date: Mon Nov 13 22:26:22 2017 +0200 Skip dirserver restrictions in small networks. --- src/or/entrynodes.c | 42 ++++++++++++++++++++++++++++++++++-------- 1 file changed, 34 insertions(+), 8 deletions(-) diff --git a/src/or/entrynodes.c b/src/or/entrynodes.c index f2ca7aac2..1cc24d8d6 100644 --- a/src/or/entrynodes.c +++ b/src/or/entrynodes.c @@ -1472,12 +1472,45 @@ guard_create_exit_restriction(const uint8_t *exit_id) return rst; } -/** Allocate and return an outdated md guard restriction. */ +/** If we have less than these many configured bridges, don't set dirserver + * restrictions because we might blacklist all of them. */ +#define TOO_FEW_BRIDGES_FOR_RESTRICTION 10 + +/** Return true if we should set md dirserver restrictions. We might not want + * to set those if our network is too restricted, since we don't want to + * blacklist all our nodes. */ +static int +should_set_md_dirserver_restriction(void) +{ + const guard_selection_t *gs = get_guard_selection_info(); + + /* Don't set a restriction if we are on a restricted guard selection */ + if (gs->type == GS_TYPE_RESTRICTED) { + return 0; + } + + /* Don't set restriction if we are using bridges and have too few of those */ + if (gs->type == GS_TYPE_BRIDGE && gs->sampled_entry_guards) { + int num_sampled_guards = smartlist_len(gs->sampled_entry_guards); + if (num_sampled_guards < TOO_FEW_BRIDGES_FOR_RESTRICTION) { + return 0; + } + } + + return 1; +} + +/** Allocate and return an outdated md guard restriction. Return NULL if no + * such restriction is needed. */ STATIC entry_guard_restriction_t * guard_create_dirserver_md_restriction(void) { entry_guard_restriction_t *rst = NULL; + if (!should_set_md_dirserver_restriction()) { + return NULL; + } + rst = tor_malloc_zero(sizeof(entry_guard_restriction_t)); rst->type = RST_OUTDATED_MD_DIRSERVER; @@ -1504,13 +1537,6 @@ guard_obeys_exit_restriction(const entry_guard_t *guard, static int guard_obeys_md_dirserver_restriction(const entry_guard_t *guard) { - /* Don't enforce dirserver restrictions for bridges since we might not have - * many of those. Be willing to try them over and over again for now. */ - /* XXX: Improvement might be possible here */ - if (guard->bridge_addr) { - return 1; - } - /* If this guard is an outdated dirserver, don't use it. */ if (microdesc_relay_is_outdated_dirserver(guard->identity)) { log_info(LD_GENERAL, "Skipping %s dirserver: outdated",