Commit 862a9974 authored by Roger Dingledine's avatar Roger Dingledine
Browse files

when we were cannibalizing a circuit with a particular exit 

node in mind, we weren't checking to see if that exit node
was already present earlier in the circuit. oops.


svn:r5357
parent 4d1c6bbf

src/or/circuitlist.c

+20 −5
Original line number Diff line number Diff line
@@ -99,7 +99,7 @@ circuit_set_circid_orconn(circuit_t *circ, uint16_t id, 
    _last_circid_orconn_ent = NULL;

  }



  if (old_conn) {

  if (old_conn) { /* we may need to remove it from the conn-circid map */

    search.circ_id = old_id;

    search.or_conn = old_conn;

    found = RB_FIND(orconn_circid_tree, &orconn_circid_circuit_map, &search);
@@ -112,6 +112,7 @@ circuit_set_circid_orconn(circuit_t *circ, uint16_t id, 
  if (conn == NULL)

    return;



  /* now add the new one to the conn-circid map */

  search.circ_id = id;

  search.or_conn = conn;

  found = RB_FIND(orconn_circid_tree, &orconn_circid_circuit_map, &search);
@@ -549,15 +550,18 @@ circuit_get_rendezvous(const char *cookie) 
}



/** Return a circuit that is open, has specified <b>purpose</b>,

 * has a timestamp_dirty value of 0, and is uptime/capacity/internal

 * if required; or NULL if no circuit fits this description.

 * has a timestamp_dirty value of 0, is uptime/capacity/internal

 * if required, and if info is defined, does not already use info

 * as any of its hops; or NULL if no circuit fits this description.

 *

 * Avoid returning need_uptime circuits if not necessary.

 *

 * FFFF As a more important goal, not yet implemented, avoid returning

 * internal circuits if not necessary.

 */

circuit_t *

circuit_get_clean_open(uint8_t purpose, int need_uptime,

circuit_find_to_cannibalize(uint8_t purpose, extend_info_t *info,

                            int need_uptime,

                            int need_capacity, int internal)

{

  circuit_t *circ;
@@ -574,8 +578,19 @@ circuit_get_clean_open(uint8_t purpose, int need_uptime, 
        (!need_uptime || circ->build_state->need_uptime) &&

        (!need_capacity || circ->build_state->need_capacity) &&

        (!internal || circ->build_state->is_internal)) {

      if (info) {

        /* need to make sure we don't duplicate hops */

        crypt_path_t *hop = circ->cpath;

        do {

          if (!memcmp(hop->extend_info->identity_digest,

                      info->identity_digest, DIGEST_LEN))

            goto next;

          hop=hop->next;

        } while (hop!=circ->cpath);

      }

      if (!best || (best->build_state->need_uptime && !need_uptime))

        best = circ;

      next:

    }

  }

  return best;

src/or/circuituse.c

+4 −3
Original line number Diff line number Diff line
@@ -756,8 +756,9 @@ circuit_launch_by_extend_info(uint8_t purpose, extend_info_t *info, 
  if ((info || purpose != CIRCUIT_PURPOSE_C_GENERAL) &&

      purpose != CIRCUIT_PURPOSE_TESTING) {

    /* see if there are appropriate circs available to cannibalize. */

    if ((circ = circuit_get_clean_open(CIRCUIT_PURPOSE_C_GENERAL, need_uptime,

                                       need_capacity, internal))) {

    circ = circuit_find_to_cannibalize(CIRCUIT_PURPOSE_C_GENERAL, info,

                                       need_uptime, need_capacity, internal);

    if (circ) {

      info(LD_CIRC,"Cannibalizing circ '%s' for purpose %d",

             build_state_get_exit_nickname(circ->build_state), purpose);

      circ->purpose = purpose;
@@ -779,7 +780,7 @@ circuit_launch_by_extend_info(uint8_t purpose, extend_info_t *info, 
            return NULL;

          break;

        default:

          warn(LD_BUG, "Bug: unexpected purpose %d when cannibalizing a general circ.", purpose);

          warn(LD_BUG, "Bug: unexpected purpose %d when cannibalizing a circ.", purpose);

          tor_fragile_assert();

          return NULL;

      }

src/or/or.h

+3 −2
Original line number Diff line number Diff line
@@ -1443,7 +1443,8 @@ circuit_t *circuit_get_by_rend_query_and_purpose(const char *rend_query, uint8_t 
circuit_t *circuit_get_next_by_pk_and_purpose(circuit_t *start,

                                         const char *digest, uint8_t purpose);

circuit_t *circuit_get_rendezvous(const char *cookie);

circuit_t *circuit_get_clean_open(uint8_t purpose, int need_uptime,

circuit_t *circuit_find_to_cannibalize(uint8_t purpose, extend_info_t *info,

                                       int need_uptime,

                                       int need_capacity, int internal);

void circuit_mark_all_unused_circs(void);

void circuit_expire_all_dirty_circs(void);