diff options
Diffstat (limited to 'src/or/dirvote.c')
| -rw-r--r-- | src/or/dirvote.c | 136 |
1 files changed, 119 insertions, 17 deletions
diff --git a/src/or/dirvote.c b/src/or/dirvote.c index 7739c52d15..b54049d5de 100644 --- a/src/or/dirvote.c +++ b/src/or/dirvote.c @@ -16,6 +16,7 @@ #include "router.h" #include "routerlist.h" #include "routerparse.h" +#include "entrynodes.h" /* needed for guardfraction methods */ /** * \file dirvote.c @@ -1023,6 +1024,86 @@ networkstatus_compute_bw_weights_v10(smartlist_t *chunks, int64_t G, return 1; } +/** Update total bandwidth weights (G/M/E/D/T) with the bandwidth of + * the router in <b>rs</b>. */ +static void +update_total_bandwidth_weights(const routerstatus_t *rs, + int is_exit, int is_guard, + int64_t *G, int64_t *M, int64_t *E, int64_t *D, + int64_t *T) +{ + int default_bandwidth = rs->bandwidth_kb; + int guardfraction_bandwidth = 0; + + if (!rs->has_bandwidth) { + log_info(LD_BUG, "Missing consensus bandwidth for router %s", + rs->nickname); + return; + } + + /* If this routerstatus represents a guard that we have + * guardfraction information on, use it to calculate its actual + * bandwidth. From proposal236: + * + * Similarly, when calculating the bandwidth-weights line as in + * section 3.8.3 of dir-spec.txt, directory authorities should treat N + * as if fraction F of its bandwidth has the guard flag and (1-F) does + * not. So when computing the totals G,M,E,D, each relay N with guard + * visibility fraction F and bandwidth B should be added as follows: + * + * G' = G + F*B, if N does not have the exit flag + * M' = M + (1-F)*B, if N does not have the exit flag + * + * or + * + * D' = D + F*B, if N has the exit flag + * E' = E + (1-F)*B, if N has the exit flag + * + * In this block of code, we prepare the bandwidth values by setting + * the default_bandwidth to F*B and guardfraction_bandwidth to (1-F)*B. */ + if (rs->has_guardfraction) { + guardfraction_bandwidth_t guardfraction_bw; + + tor_assert(is_guard); + + guard_get_guardfraction_bandwidth(&guardfraction_bw, + rs->bandwidth_kb, + rs->guardfraction_percentage); + + default_bandwidth = guardfraction_bw.guard_bw; + guardfraction_bandwidth = guardfraction_bw.non_guard_bw; + } + + /* Now calculate the total bandwidth weights with or without + guardfraction. Depending on the flags of the relay, add its + bandwidth to the appropriate weight pool. If it's a guard and + guardfraction is enabled, add its bandwidth to both pools as + indicated by the previous comment. */ + *T += default_bandwidth; + if (is_exit && is_guard) { + + *D += default_bandwidth; + if (rs->has_guardfraction) { + *E += guardfraction_bandwidth; + } + + } else if (is_exit) { + + *E += default_bandwidth; + + } else if (is_guard) { + + *G += default_bandwidth; + if (rs->has_guardfraction) { + *M += guardfraction_bandwidth; + } + + } else { + + *M += default_bandwidth; + } +} + /** Given a list of vote networkstatus_t in <b>votes</b>, our public * authority <b>identity_key</b>, our private authority <b>signing_key</b>, * and the number of <b>total_authorities</b> that we believe exist in our @@ -1291,8 +1372,11 @@ networkstatus_compute_consensus(smartlist_t *votes, sizeof(uint32_t)); uint32_t *measured_bws_kb = tor_calloc(smartlist_len(votes), sizeof(uint32_t)); + uint32_t *measured_guardfraction = tor_calloc(smartlist_len(votes), + sizeof(uint32_t)); int num_bandwidths; int num_mbws; + int num_guardfraction_inputs; int *n_voter_flags; /* n_voter_flags[j] is the number of flags that * votes[j] knows about. */ @@ -1401,7 +1485,7 @@ networkstatus_compute_consensus(smartlist_t *votes, /* We need to know how many votes measure bandwidth. */ n_authorities_measuring_bandwidth = 0; - SMARTLIST_FOREACH(votes, networkstatus_t *, v, + SMARTLIST_FOREACH(votes, const networkstatus_t *, v, if (v->has_measured_bws) { ++n_authorities_measuring_bandwidth; } @@ -1443,6 +1527,7 @@ networkstatus_compute_consensus(smartlist_t *votes, smartlist_clear(versions); num_bandwidths = 0; num_mbws = 0; + num_guardfraction_inputs = 0; /* Okay, go through all the entries for this digest. */ SMARTLIST_FOREACH_BEGIN(votes, networkstatus_t *, v) { @@ -1476,6 +1561,12 @@ networkstatus_compute_consensus(smartlist_t *votes, chosen_name = rs->status.nickname; } + /* Count guardfraction votes and note down the values. */ + if (rs->status.has_guardfraction) { + measured_guardfraction[num_guardfraction_inputs++] = + rs->status.guardfraction_percentage; + } + /* count bandwidths */ if (rs->has_measured_bw) measured_bws_kb[num_mbws++] = rs->measured_bw_kb; @@ -1565,6 +1656,17 @@ networkstatus_compute_consensus(smartlist_t *votes, chosen_version = NULL; } + /* If it's a guard and we have enough guardfraction votes, + calculate its consensus guardfraction value. */ + if (is_guard && num_guardfraction_inputs > 2 && + consensus_method >= MIN_METHOD_FOR_GUARDFRACTION) { + rs_out.has_guardfraction = 1; + rs_out.guardfraction_percentage = median_uint32(measured_guardfraction, + num_guardfraction_inputs); + /* final value should be an integer percentage! */ + tor_assert(rs_out.guardfraction_percentage <= 100); + } + /* Pick a bandwidth */ if (num_mbws > 2) { rs_out.has_bandwidth = 1; @@ -1586,21 +1688,11 @@ networkstatus_compute_consensus(smartlist_t *votes, /* Fix bug 2203: Do not count BadExit nodes as Exits for bw weights */ is_exit = is_exit && !is_bad_exit; + /* Update total bandwidth weights with the bandwidths of this router. */ { - if (rs_out.has_bandwidth) { - T += rs_out.bandwidth_kb; - if (is_exit && is_guard) - D += rs_out.bandwidth_kb; - else if (is_exit) - E += rs_out.bandwidth_kb; - else if (is_guard) - G += rs_out.bandwidth_kb; - else - M += rs_out.bandwidth_kb; - } else { - log_warn(LD_BUG, "Missing consensus bandwidth for router %s", - rs_out.nickname); - } + update_total_bandwidth_weights(&rs_out, + is_exit, is_guard, + &G, &M, &E, &D, &T); } /* Ok, we already picked a descriptor digest we want to list @@ -1719,11 +1811,21 @@ networkstatus_compute_consensus(smartlist_t *votes, smartlist_add(chunks, tor_strdup("\n")); /* Now the weight line. */ if (rs_out.has_bandwidth) { + char *guardfraction_str = NULL; int unmeasured = rs_out.bw_is_unmeasured && consensus_method >= MIN_METHOD_TO_CLIP_UNMEASURED_BW; - smartlist_add_asprintf(chunks, "w Bandwidth=%d%s\n", + + /* If we have guardfraction info, include it in the 'w' line. */ + if (rs_out.has_guardfraction) { + tor_asprintf(&guardfraction_str, + " GuardFraction=%u", rs_out.guardfraction_percentage); + } + smartlist_add_asprintf(chunks, "w Bandwidth=%d%s%s\n", rs_out.bandwidth_kb, - unmeasured?" Unmeasured=1":""); + unmeasured?" Unmeasured=1":"", + guardfraction_str ? guardfraction_str : ""); + + tor_free(guardfraction_str); } /* Now the exitpolicy summary line. */ |