Commit 0e5abcb6 authored by Nick Mathewson's avatar Nick Mathewson 🦞
Browse files

Skip non-running routers for exit node selection 


svn:r842
parent 25ac8857

src/or/onion.c

+23 −5
Original line number Diff line number Diff line
@@ -234,6 +234,7 @@ static routerinfo_t *choose_good_exit_server(directory_t *dir) 
  int best_support_idx = -1;

  int best_maybe_support_idx = -1;

  int n_best_support=0, n_best_maybe_support=0;

  int n_running_routers=0;

  

  get_connection_array(&carray, &n_connections);
@@ -257,8 +258,11 @@ static routerinfo_t *choose_good_exit_server(directory_t *dir) 
  n_maybe_supported = tor_malloc(sizeof(int)*dir->n_routers);

  for (i = 0; i < dir->n_routers; ++i) {   /* iterate over routers */

    n_supported[i] = n_maybe_supported[i] = 0;

    if(!dir->routers[i]->is_running)

    if(!dir->routers[i]->is_running) {

      n_supported[i] = n_maybe_supported[i] = -1;

      continue; /* skip routers which are known to be down */

    }

    ++n_running_routers;

    for (j = 0; j < n_connections; ++j) { /* iterate over connections */

      if (carray[j]->type != CONN_TYPE_AP || 

          carray[j]->state == AP_CONN_STATE_CIRCUIT_WAIT ||
@@ -297,7 +301,7 @@ static routerinfo_t *choose_good_exit_server(directory_t *dir) 
         n_best_maybe_support, best_maybe_support, n_pending_connections);

  /* If any routers definitely support any pending connections, choose one

   * at random. */

  if (best_support) {

  if (best_support > 0) {

    i = crypto_pseudo_rand_int(n_best_support);

    /* Iterate over the routers, until we find the i-th one such that

     * n_supported[j] == best_support
@@ -317,7 +321,7 @@ static routerinfo_t *choose_good_exit_server(directory_t *dir) 
  }

  /* If any routers _maybe_ support pending connections, choose one at

   * random, as above.  */

  if (best_maybe_support) {

  if (best_maybe_support > 0) {

    i = crypto_pseudo_rand_int(n_best_maybe_support);

    for (j = best_maybe_support_idx; j < dir->n_routers; ++j) {

      if (n_maybe_supported[j] == best_maybe_support) {
@@ -334,9 +338,23 @@ static routerinfo_t *choose_good_exit_server(directory_t *dir) 
  }

  /* Either there are no pending connections, or no routers even seem to

   * possibly support any of them.  Choose a router at random. */

  /* XXX should change to not choose non-running routers */

  tor_free(n_supported); tor_free(n_maybe_supported);

  i = crypto_pseudo_rand_int(dir->n_routers);

  if (!n_running_routers) {

    log_fn(LOG_WARN, "No routers seem to be running; can't choose an exit.");

    return NULL;

  }

  i = crypto_pseudo_rand_int(n_running_routers);

  /* Iterate over the routers, till we find the i'th one that has ->is_running

   */

  for (j = 0; j < dir->n_routers; ++j) {

    if (dir->routers[j]->is_running) {

      if (i) {

        --i;

      } else {

        return dir->routers[j];

      }

    }

  }

  log_fn(LOG_DEBUG, "Chose exit server '%s'", dir->routers[i]->nickname);

  return dir->routers[i];

}