/** Process a 'destroy' <b>cell</b> that just arrived from
* <b>conn</b>. Find the circ that it refers to (if any).
*
* If the circ is in state
* onionskin_pending, then call onion_pending_remove() to remove it
* from the pending onion list (note that if it's already being
* processed by the cpuworker, it won't be in the list anymore; but
* when the cpuworker returns it, the circuit will be gone, and the
* cpuworker response will be dropped).
*
* Then mark the circuit for close (which marks all edges for close,
* and passes the destroy cell onward if necessary).
*/
static void
command_process_destroy_cell(cell_t *cell, or_connection_t *conn)
{
circuit_t *circ;
int reason;
circ = circuit_get_by_circid_orconn(cell->circ_id, conn);
reason = (uint8_t)cell->payload[0];
if (!circ) {
log_info(LD_OR,"unknown circuit %d on connection from %s:%d. Dropping.",
cell->circ_id, conn->_base.address, conn->_base.port);
return;
}
log_debug(LD_OR,"Received for circID %d.",cell->circ_id);
if (!CIRCUIT_IS_ORIGIN(circ) &&
cell->circ_id == TO_OR_CIRCUIT(circ)->p_circ_id) {
/* the destroy came from behind */
circuit_set_p_circid_orconn(TO_OR_CIRCUIT(circ), 0, NULL);
circuit_mark_for_close(circ, reason|END_CIRC_REASON_FLAG_REMOTE);
} else { /* the destroy came from ahead */
circuit_set_n_circid_orconn(circ, 0, NULL);
if (CIRCUIT_IS_ORIGIN(circ)) {
circuit_mark_for_close(circ, reason|END_CIRC_REASON_FLAG_REMOTE);
} else {
char payload[1];
log_debug(LD_OR, "Delivering 'truncated' back.");
payload[0] = (char)reason;
relay_send_command_from_edge(0, circ, RELAY_COMMAND_TRUNCATED,
payload, sizeof(payload), NULL);
}
}
}
/** Allocate a new or_circuit_t, connected to <b>p_conn</b> as
* <b>p_circ_id</b>. If <b>p_conn</b> is NULL, the circuit is unattached. */
or_circuit_t *
or_circuit_new(circid_t p_circ_id, or_connection_t *p_conn)
{
/* CircIDs */
or_circuit_t *circ;
circ = tor_malloc_zero(sizeof(or_circuit_t));
circ->_base.magic = OR_CIRCUIT_MAGIC;
if (p_conn)
circuit_set_p_circid_orconn(circ, p_circ_id, p_conn);
circ->remaining_relay_early_cells = MAX_RELAY_EARLY_CELLS_PER_CIRCUIT;
init_circuit_base(TO_CIRCUIT(circ));
/* Initialize the cell_ewma_t structure */
/* Initialize the cell counts to 0 */
circ->p_cell_ewma.cell_count = 0.0;
circ->p_cell_ewma.last_adjusted_tick = cell_ewma_get_tick();
circ->p_cell_ewma.is_for_p_conn = 1;
/* It's not in any heap yet. */
circ->p_cell_ewma.heap_index = -1;
return circ;
}
/** Allocate a new or_circuit_t, connected to <b>p_conn</b> as
* <b>p_circ_id</b>. If <b>p_conn</b> is NULL, the circuit is unattached. */
or_circuit_t *
or_circuit_new(circid_t p_circ_id, or_connection_t *p_conn)
{
/* CircIDs */
or_circuit_t *circ;
circ = tor_malloc_zero(sizeof(or_circuit_t));
circ->_base.magic = OR_CIRCUIT_MAGIC;
if (p_conn)
circuit_set_p_circid_orconn(circ, p_circ_id, p_conn);
circ->remaining_relay_early_cells = MAX_RELAY_EARLY_CELLS_PER_CIRCUIT;
init_circuit_base(TO_CIRCUIT(circ));
return circ;
}
/** For each circuit that has <b>conn</b> as n_conn or p_conn, unlink the
* circuit from the orconn,circid map, and mark it for close if it hasn't
* been marked already.
*/
void
circuit_unlink_all_from_or_conn(or_connection_t *conn, int reason)
{
circuit_t *circ;
connection_or_unlink_all_active_circs(conn);
for (circ = global_circuitlist; circ; circ = circ->next) {
int mark = 0;
if (circ->n_conn == conn) {
circuit_set_n_circid_orconn(circ, 0, NULL);
mark = 1;
}
if (! CIRCUIT_IS_ORIGIN(circ)) {
or_circuit_t *or_circ = TO_OR_CIRCUIT(circ);
if (or_circ->p_conn == conn) {
circuit_set_p_circid_orconn(or_circ, 0, NULL);
mark = 1;
}
}
if (mark && !circ->marked_for_close)
circuit_mark_for_close(circ, reason);
}
}
/** Deallocate space associated with circ.
*/
static void
circuit_free(circuit_t *circ)
{
void *mem;
size_t memlen;
tor_assert(circ);
if (CIRCUIT_IS_ORIGIN(circ)) {
origin_circuit_t *ocirc = TO_ORIGIN_CIRCUIT(circ);
mem = ocirc;
memlen = sizeof(origin_circuit_t);
tor_assert(circ->magic == ORIGIN_CIRCUIT_MAGIC);
if (ocirc->build_state) {
if (ocirc->build_state->chosen_exit)
extend_info_free(ocirc->build_state->chosen_exit);
if (ocirc->build_state->pending_final_cpath)
circuit_free_cpath_node(ocirc->build_state->pending_final_cpath);
}
tor_free(ocirc->build_state);
circuit_free_cpath(ocirc->cpath);
if (ocirc->intro_key)
crypto_free_pk_env(ocirc->intro_key);
if (ocirc->rend_data)
rend_data_free(ocirc->rend_data);
} else {
or_circuit_t *ocirc = TO_OR_CIRCUIT(circ);
mem = ocirc;
memlen = sizeof(or_circuit_t);
tor_assert(circ->magic == OR_CIRCUIT_MAGIC);
if (ocirc->p_crypto)
crypto_free_cipher_env(ocirc->p_crypto);
if (ocirc->p_digest)
crypto_free_digest_env(ocirc->p_digest);
if (ocirc->n_crypto)
crypto_free_cipher_env(ocirc->n_crypto);
if (ocirc->n_digest)
crypto_free_digest_env(ocirc->n_digest);
if (ocirc->rend_splice) {
or_circuit_t *other = ocirc->rend_splice;
tor_assert(other->_base.magic == OR_CIRCUIT_MAGIC);
other->rend_splice = NULL;
}
/* remove from map. */
circuit_set_p_circid_orconn(ocirc, 0, NULL);
/* Clear cell queue _after_ removing it from the map. Otherwise our
* "active" checks will be violated. */
cell_queue_clear(ô->p_conn_cells);
}
if (circ->n_hop)
extend_info_free(circ->n_hop);
tor_free(circ->n_conn_onionskin);
/* Remove from map. */
circuit_set_n_circid_orconn(circ, 0, NULL);
/* Clear cell queue _after_ removing it from the map. Otherwise our
* "active" checks will be violated. */
cell_queue_clear(&circ->n_conn_cells);
memset(circ, 0xAA, memlen); /* poison memory */
tor_free(mem);
}
/** Deallocate space associated with circ.
*/
static void
circuit_free(circuit_t *circ)
{
void *mem;
size_t memlen;
if (!circ)
return;
if (CIRCUIT_IS_ORIGIN(circ)) {
origin_circuit_t *ocirc = TO_ORIGIN_CIRCUIT(circ);
mem = ocirc;
memlen = sizeof(origin_circuit_t);
tor_assert(circ->magic == ORIGIN_CIRCUIT_MAGIC);
if (ocirc->build_state) {
extend_info_free(ocirc->build_state->chosen_exit);
circuit_free_cpath_node(ocirc->build_state->pending_final_cpath);
cpath_ref_decref(ocirc->build_state->service_pending_final_cpath_ref);
}
tor_free(ocirc->build_state);
circuit_free_cpath(ocirc->cpath);
crypto_pk_free(ocirc->intro_key);
rend_data_free(ocirc->rend_data);
tor_free(ocirc->dest_address);
if (ocirc->socks_username) {
memwipe(ocirc->socks_username, 0x12, ocirc->socks_username_len);
tor_free(ocirc->socks_username);
}
if (ocirc->socks_password) {
memwipe(ocirc->socks_password, 0x06, ocirc->socks_password_len);
tor_free(ocirc->socks_password);
}
} else {
or_circuit_t *ocirc = TO_OR_CIRCUIT(circ);
/* Remember cell statistics for this circuit before deallocating. */
if (get_options()->CellStatistics)
rep_hist_buffer_stats_add_circ(circ, time(NULL));
mem = ocirc;
memlen = sizeof(or_circuit_t);
tor_assert(circ->magic == OR_CIRCUIT_MAGIC);
crypto_cipher_free(ocirc->p_crypto);
crypto_digest_free(ocirc->p_digest);
crypto_cipher_free(ocirc->n_crypto);
crypto_digest_free(ocirc->n_digest);
if (ocirc->rend_splice) {
or_circuit_t *other = ocirc->rend_splice;
tor_assert(other->_base.magic == OR_CIRCUIT_MAGIC);
other->rend_splice = NULL;
}
/* remove from map. */
circuit_set_p_circid_orconn(ocirc, 0, NULL);
/* Clear cell queue _after_ removing it from the map. Otherwise our
* "active" checks will be violated. */
cell_queue_clear(ô->p_conn_cells);
}
extend_info_free(circ->n_hop);
tor_free(circ->n_conn_onionskin);
/* Remove from map. */
circuit_set_n_circid_orconn(circ, 0, NULL);
/* Clear cell queue _after_ removing it from the map. Otherwise our
* "active" checks will be violated. */
cell_queue_clear(&circ->n_conn_cells);
memwipe(mem, 0xAA, memlen); /* poison memory */
tor_free(mem);
}
