diff options
Diffstat (limited to 'src/or')
| -rw-r--r-- | src/or/routerlist.c | 29 |
1 files changed, 27 insertions, 2 deletions
diff --git a/src/or/routerlist.c b/src/or/routerlist.c index 0b271f1aa3..43be8346cc 100644 --- a/src/or/routerlist.c +++ b/src/or/routerlist.c @@ -1579,6 +1579,29 @@ router_get_advertised_bandwidth_capped(routerinfo_t *router) return result; } +/** When weighting bridges, enforce these values as lower and upper + * bound for believable bandwidth, because there is no way for us + * to verify a bridge's bandwidth currently. */ +#define BRIDGE_MIN_BELIEVABLE_BANDWIDTH 20000 /* 20 kB/sec */ +#define BRIDGE_MAX_BELIEVABLE_BANDWIDTH 100000 /* 100 kB/sec */ + +/** Return the smaller of the router's configured BandwidthRate + * and its advertised capacity, making sure to stay within the + * interval between bridge-min-believe-bw and + * bridge-max-believe-bw. */ +static uint32_t +bridge_get_advertised_bandwidth_bounded(routerinfo_t *router) +{ + uint32_t result = router->bandwidthcapacity; + if (result > router->bandwidthrate) + result = router->bandwidthrate; + if (result > BRIDGE_MAX_BELIEVABLE_BANDWIDTH) + result = BRIDGE_MAX_BELIEVABLE_BANDWIDTH; + else if (result < BRIDGE_MIN_BELIEVABLE_BANDWIDTH) + result = BRIDGE_MIN_BELIEVABLE_BANDWIDTH; + return result; +} + /** Return bw*1000, unless bw*1000 would overflow, in which case return * INT32_MAX. */ static INLINE int32_t @@ -1733,7 +1756,7 @@ smartlist_choose_by_bandwidth_weights(smartlist_t *sl, if (rs && rs->has_bandwidth) { this_bw = kb_to_bytes(rs->bandwidth); } else { /* bridge or other descriptor not in our consensus */ - this_bw = router_get_advertised_bandwidth_capped(router); + this_bw = bridge_get_advertised_bandwidth_bounded(router); have_unknown = 1; } if (router_digest_is_me(router->cache_info.identity_digest)) @@ -1904,7 +1927,7 @@ smartlist_choose_by_bandwidth(smartlist_t *sl, bandwidth_weight_rule_t rule, flags |= is_exit ? 2 : 0; flags |= is_guard ? 4 : 0; } else /* bridge or other descriptor not in our consensus */ - this_bw = router_get_advertised_bandwidth_capped(router); + this_bw = bridge_get_advertised_bandwidth_bounded(router); } if (is_exit) bitarray_set(exit_bits, i); @@ -1912,6 +1935,8 @@ smartlist_choose_by_bandwidth(smartlist_t *sl, bandwidth_weight_rule_t rule, bitarray_set(guard_bits, i); if (is_known) { bandwidths[i] = (int32_t) this_bw; // safe since MAX_BELIEVABLE<INT32_MAX + // XXX this is no longer true! We don't always cap the bw anymore. Can + // a consensus make us overflow?-sh tor_assert(bandwidths[i] >= 0); if (is_guard) total_guard_bw += this_bw; |