Merge branch 'maint-0.2.1'

Changes in version 0.2.1.23 - 2010-0?-??

  o Major bugfixes (performance):

    - We were selecting our guards uniformly at random, and then weighting

      which of our guards we'd use uniformly at random. This imbalance

      meant that Tor clients were severely limited on throughput (and

      probably latency too) by the first hop in their circuit. Now we

      select guards weighted by currently advertised bandwidth. We also

      automatically discard guards picked using the old algorithm. Fixes

      bug 1217; bugfix on 0.2.1.3-alpha. Found by Mike Perry.

  o Minor features:

    - Avoid a mad rush at the beginning of each month when each client

      rotates half of its guards. Instead we spread the rotation out

      throughout the month, but we still avoid leaving a precise timestamp

      in the state file about when we first picked the guard. Improves

      over the behavior introduced in 0.1.2.17.

Changes in version 0.2.2.7-alpha - 2010-01-19

  o Major features (performance):

    - When choosing which cells to relay first, relays can now favor

static int onion_append_hop(crypt_path_t **head_ptr, extend_info_t *choice);

static void entry_guards_changed(void);

static time_t start_of_month(time_t when);

/** Make a note that we're running unit tests (rather than running Tor

 * itself), so we avoid clobbering our state file. */

  routerinfo_t *r, *choice;

  smartlist_t *excluded;

  or_options_t *options = get_options();

  router_crn_flags_t flags = 0;

  router_crn_flags_t flags = CRN_NEED_GUARD;

  if (state && options->UseEntryGuards &&

      (purpose != CIRCUIT_PURPOSE_TESTING || options->BridgeRelay)) {

  }

  if (state) {

    flags |= CRN_NEED_GUARD;

    if (state->need_uptime)

      flags |= CRN_NEED_UPTIME;

    if (state->need_capacity)

  log_info(LD_CIRC, "Chose '%s' as new entry guard.", router->nickname);

  strlcpy(entry->nickname, router->nickname, sizeof(entry->nickname));

  memcpy(entry->identity, router->cache_info.identity_digest, DIGEST_LEN);

  entry->chosen_on_date = start_of_month(time(NULL));

  /* Choose expiry time smudged over the past month. The goal here

   * is to a) spread out when Tor clients rotate their guards, so they

   * don't all select them on the same day, and b) avoid leaving a

   * precise timestamp in the state file about when we first picked

   * this guard. For details, see the Jan 2010 or-dev thread. */

  entry->chosen_on_date = time(NULL) - crypto_rand_int(3600*24*30);

  entry->chosen_by_version = tor_strdup(VERSION);

  if (chosen) /* prepend */

    smartlist_insert(entry_guards, 0, entry);

remove_obsolete_entry_guards(void)

{

  int changed = 0, i;

  time_t this_month = start_of_month(time(NULL));

  time_t now = time(NULL);

  for (i = 0; i < smartlist_len(entry_guards); ++i) {

    entry_guard_t *entry = smartlist_get(entry_guards, i);

    } else if (tor_version_parse(ver, &v)) {

      msg = "does not seem to be from any recognized version of Tor";

      version_is_bad = 1;

    } else if ((tor_version_as_new_as(ver, "0.1.0.10-alpha") &&

                !tor_version_as_new_as(ver, "0.1.2.16-dev")) ||

               (tor_version_as_new_as(ver, "0.2.0.0-alpha") &&

                !tor_version_as_new_as(ver, "0.2.0.6-alpha"))) {

    } else {

      size_t len = strlen(ver)+5;

      char *tor_ver = tor_malloc(len);

      tor_snprintf(tor_ver, len, "Tor %s", ver);

      if ((tor_version_as_new_as(tor_ver, "0.1.0.10-alpha") &&

           !tor_version_as_new_as(tor_ver, "0.1.2.16-dev")) ||

          (tor_version_as_new_as(tor_ver, "0.2.0.0-alpha") &&

           !tor_version_as_new_as(tor_ver, "0.2.0.6-alpha")) ||

          /* above are bug 440; below are bug 1217 */

          (tor_version_as_new_as(tor_ver, "0.2.1.3-alpha") &&

           !tor_version_as_new_as(tor_ver, "0.2.1.23")) ||

          (tor_version_as_new_as(tor_ver, "0.2.2.0-alpha") &&

           !tor_version_as_new_as(tor_ver, "0.2.2.7-alpha"))) {

        msg = "was selected without regard for guard bandwidth";

        version_is_bad = 1;

    } else if (entry->chosen_on_date + 3600*24*35 < this_month) {

      /* It's been more than a month, and probably more like two since

       * chosen_on_date is clipped to the beginning of its month. */

      }

      tor_free(tor_ver);

    }

    if (!version_is_bad && entry->chosen_on_date + 3600*24*60 < now) {

      /* It's been 2 months since the date listed in our state file. */

      msg = "was selected several months ago";

      date_is_bad = 1;

    }

  return r;

}

/** Helper: Return the start of the month containing <b>time</b>. */

static time_t

start_of_month(time_t now)

{

  struct tm tm;

  tor_gmtime_r(&now, &tm);

  tm.tm_sec = 0;

  tm.tm_min = 0;

  tm.tm_hour = 0;

  tm.tm_mday = 1;

  return tor_timegm(&tm);

}

/** Parse <b>state</b> and learn about the entry guards it describes.

 * If <b>set</b> is true, and there are no errors, replace the global

 * entry_list with what we find.

     } else {

       if (state_version) {

         e->chosen_by_version = tor_strdup(state_version);

         e->chosen_on_date = start_of_month(time(NULL));

         e->chosen_on_date = time(NULL) - crypto_rand_int(3600*24*30);

       }

     }

   });