Commit 90e143e6 authored by Nick Mathewson's avatar Nick Mathewson 🦀
Browse files

Remove a possible source of error in circID picking. 


svn:r824
parent e5d6e7db

src/or/circuit.c

+7 −11
Original line number Diff line number Diff line
@@ -7,7 +7,7 @@ 
extern or_options_t options; /* command-line and config-file options */



static void circuit_free_cpath_node(crypt_path_t *victim);

static circ_id_t get_unique_circ_id_by_addr_port(uint32_t addr, uint16_t port, int circ_id_type);  

static circ_id_t get_unique_circ_id_by_conn(connection_t *conn, int circ_id_type);  



unsigned long stats_n_relay_cells_relayed = 0;

unsigned long stats_n_relay_cells_delivered = 0;
@@ -121,17 +121,12 @@ static void circuit_free_cpath_node(crypt_path_t *victim) { 
}



/* return 0 if can't get a unique circ_id. */

static circ_id_t get_unique_circ_id_by_addr_port(uint32_t addr, uint16_t port, int circ_id_type) {

static circ_id_t get_unique_circ_id_by_conn(connection_t *conn, int circ_id_type) {

  circ_id_t test_circ_id;

  connection_t *conn;

  uint16_t high_bit;

  assert(conn && conn->type == CONN_TYPE_OR);



  high_bit = (circ_id_type == CIRC_ID_TYPE_HIGHER) ? 1<<15 : 0;

  conn = connection_exact_get_by_addr_port(addr,port);

  /* XXX race condition: if conn is marked_for_close it won't be noticed */

  if (!conn)

    return (1|high_bit); /* No connection exists; conflict is impossible. */



  do {

    /* Sequentially iterate over test_circ_id=1...1<<15-1 until we find an

     * circID such that (high_bit|test_circ_id) is not already used. */
@@ -771,9 +766,10 @@ int circuit_send_next_onion_skin(circuit_t *circ) { 
  assert(circ && circ->cpath);



  if(circ->cpath->state == CPATH_STATE_CLOSED) {

    assert(circ->n_conn && circ->n_conn->type == CONN_TYPE_OR);

    

    log_fn(LOG_DEBUG,"First skin; sending create cell.");

    circ->n_circ_id = get_unique_circ_id_by_addr_port(circ->n_addr, circ->n_port, CIRC_ID_TYPE_BOTH);

    circ->n_circ_id = get_unique_circ_id_by_conn(circ->n_conn, CIRC_ID_TYPE_BOTH);



    memset(&cell, 0, sizeof(cell_t));

    cell.command = CELL_CREATE;
@@ -875,7 +871,7 @@ int circuit_extend(cell_t *cell, circuit_t *circ) { 
  circ_id_type = decide_circ_id_type(options.Nickname, n_conn->nickname);



  log_fn(LOG_DEBUG,"circ_id_type = %u.",circ_id_type);

  circ->n_circ_id = get_unique_circ_id_by_addr_port(circ->n_addr, circ->n_port, circ_id_type);

  circ->n_circ_id = get_unique_circ_id_by_conn(circ->n_conn, circ_id_type);

  if(!circ->n_circ_id) {

    log_fn(LOG_WARN,"failed to get unique circID.");

    return -1;