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Split connection_edge_process_relay_cell() in two functions.

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One function does the validation, the other does the handling.
This commit is contained in:
George Kadianakis 2019-07-23 13:01:12 +03:00
parent 54ad92a240
commit 7a032c5e48
1 changed files with 399 additions and 376 deletions
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775
src/core/or/relay.c
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@ -1576,6 +1576,403 @@ process_sendme_cell(const relay_header_t *rh, const cell_t *cell,
return 0;
}
/** A helper for connection_edge_process_relay_cell(): Actually handles the
* cell that we received on the connection.
*
* The arguments are the same as in the parent function
* connection_edge_process_relay_cell(), plus the relay header <b>rh</b> as
* unpacked by the parent function, and <b>optimistic_data</b> as set by the
* parent function.
*/
static int
handle_relay_command(cell_t *cell, circuit_t *circ,
edge_connection_t *conn,
crypt_path_t *layer_hint,
relay_header_t *rh,
int optimistic_data)
{
unsigned domain = layer_hint?LD_APP:LD_EXIT;
int reason;
tor_assert(rh);
switch (rh->command) {
case RELAY_COMMAND_DROP:
/* Already examined in circpad_deliver_recognized_relay_cell_events */
return 0;
case RELAY_COMMAND_PADDING_NEGOTIATE:
circpad_handle_padding_negotiate(circ, cell);
return 0;
case RELAY_COMMAND_PADDING_NEGOTIATED:
if (circpad_handle_padding_negotiated(circ, cell, layer_hint) == 0)
circuit_read_valid_data(TO_ORIGIN_CIRCUIT(circ), rh->length);
return 0;
}
/* If this is a padding circuit we don't need to parse any other commands
* than the padding ones. Just drop them to the floor. */
if (circ->purpose == CIRCUIT_PURPOSE_C_CIRCUIT_PADDING) {
log_info(domain, "Ignored cell (%d) that arrived in padding circuit.",
rh.command);
return 0;
}
switch (rh.command) {
case RELAY_COMMAND_BEGIN:
case RELAY_COMMAND_BEGIN_DIR:
if (layer_hint &&
circ->purpose != CIRCUIT_PURPOSE_S_REND_JOINED) {
log_fn(LOG_PROTOCOL_WARN, LD_APP,
"Relay begin request unsupported at AP. Dropping.");
return 0;
}
if (circ->purpose == CIRCUIT_PURPOSE_S_REND_JOINED &&
layer_hint != TO_ORIGIN_CIRCUIT(circ)->cpath->prev) {
log_fn(LOG_PROTOCOL_WARN, LD_APP,
"Relay begin request to Hidden Service "
"from intermediary node. Dropping.");
return 0;
}
if (conn) {
log_fn(LOG_PROTOCOL_WARN, domain,
"Begin cell for known stream. Dropping.");
return 0;
}
if (rh->command == RELAY_COMMAND_BEGIN_DIR &&
circ->purpose != CIRCUIT_PURPOSE_S_REND_JOINED) {
/* Assign this circuit and its app-ward OR connection a unique ID,
* so that we can measure download times. The local edge and dir
* connection will be assigned the same ID when they are created
* and linked. */
static uint64_t next_id = 0;
circ->dirreq_id = ++next_id;
TO_OR_CIRCUIT(circ)->p_chan->dirreq_id = circ->dirreq_id;
}
return connection_exit_begin_conn(cell, circ);
case RELAY_COMMAND_DATA:
++stats_n_data_cells_received;
/* Update our circuit-level deliver window that we received a DATA cell.
* If the deliver window goes below 0, we end the circuit and stream due
* to a protocol failure. */
if (sendme_circuit_data_received(circ, layer_hint) < 0) {
log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL,
"(relay data) circ deliver_window below 0. Killing.");
connection_edge_end_close(conn, END_STREAM_REASON_TORPROTOCOL);
return -END_CIRC_REASON_TORPROTOCOL;
}
/* Consider sending a circuit-level SENDME cell. */
sendme_circuit_consider_sending(circ, layer_hint);
if (rh->stream_id == 0) {
log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, "Relay data cell with zero "
"stream_id. Dropping.");
return 0;
} else if (!conn) {
if (CIRCUIT_IS_ORIGIN(circ)) {
origin_circuit_t *ocirc = TO_ORIGIN_CIRCUIT(circ);
if (connection_half_edge_is_valid_data(ocirc->half_streams,
rh->stream_id)) {
circuit_read_valid_data(ocirc, rh->length);
log_info(domain,
"data cell on circ %u valid on half-closed "
"stream id %d", ocirc->global_identifier, rh->stream_id);
}
}
log_info(domain,"data cell dropped, unknown stream (streamid %d).",
rh->stream_id);
return 0;
}
/* Update our stream-level deliver window that we just received a DATA
* cell. Going below 0 means we have a protocol level error so the
* stream and circuit are closed. */
if (sendme_stream_data_received(conn) < 0) {
log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL,
"(relay data) conn deliver_window below 0. Killing.");
connection_edge_end_close(conn, END_STREAM_REASON_TORPROTOCOL);
return -END_CIRC_REASON_TORPROTOCOL;
}
/* Total all valid application bytes delivered */
if (CIRCUIT_IS_ORIGIN(circ) && rh->length > 0) {
circuit_read_valid_data(TO_ORIGIN_CIRCUIT(circ), rh->length);
}
stats_n_data_bytes_received += rh->length;
connection_buf_add((char*)(cell->payload + RELAY_HEADER_SIZE),
rh->length, TO_CONN(conn));
#ifdef MEASUREMENTS_21206
/* Count number of RELAY_DATA cells received on a linked directory
* connection. */
connection_t *linked_conn = TO_CONN(conn)->linked_conn;
if (linked_conn && linked_conn->type == CONN_TYPE_DIR) {
++(TO_DIR_CONN(linked_conn)->data_cells_received);
}
#endif /* defined(MEASUREMENTS_21206) */
if (!optimistic_data) {
/* Only send a SENDME if we're not getting optimistic data; otherwise
* a SENDME could arrive before the CONNECTED.
*/
sendme_connection_edge_consider_sending(conn);
}
return 0;
case RELAY_COMMAND_END:
reason = rh->length > 0 ?
get_uint8(cell->payload+RELAY_HEADER_SIZE) : END_STREAM_REASON_MISC;
if (!conn) {
if (CIRCUIT_IS_ORIGIN(circ)) {
origin_circuit_t *ocirc = TO_ORIGIN_CIRCUIT(circ);
if (connection_half_edge_is_valid_end(ocirc->half_streams,
rh->stream_id)) {
circuit_read_valid_data(ocirc, rh->length);
log_info(domain,
"end cell (%s) on circ %u valid on half-closed "
"stream id %d",
stream_end_reason_to_string(reason),
ocirc->global_identifier, rh->stream_id);
return 0;
}
}
log_info(domain,"end cell (%s) dropped, unknown stream.",
stream_end_reason_to_string(reason));
return 0;
}
/* XXX add to this log_fn the exit node's nickname? */
log_info(domain,TOR_SOCKET_T_FORMAT": end cell (%s) for stream %d. "
"Removing stream.",
conn->base_.s,
stream_end_reason_to_string(reason),
conn->stream_id);
if (conn->base_.type == CONN_TYPE_AP) {
entry_connection_t *entry_conn = EDGE_TO_ENTRY_CONN(conn);
if (entry_conn->socks_request &&
!entry_conn->socks_request->has_finished)
log_warn(LD_BUG,
"open stream hasn't sent socks answer yet? Closing.");
}
/* We just *got* an end; no reason to send one. */
conn->edge_has_sent_end = 1;
if (!conn->end_reason)
conn->end_reason = reason | END_STREAM_REASON_FLAG_REMOTE;
if (!conn->base_.marked_for_close) {
/* only mark it if not already marked. it's possible to
* get the 'end' right around when the client hangs up on us. */
connection_mark_and_flush(TO_CONN(conn));
/* Total all valid application bytes delivered */
if (CIRCUIT_IS_ORIGIN(circ)) {
circuit_read_valid_data(TO_ORIGIN_CIRCUIT(circ), rh->length);
}
}
return 0;
case RELAY_COMMAND_EXTEND:
case RELAY_COMMAND_EXTEND2: {
static uint64_t total_n_extend=0, total_nonearly=0;
total_n_extend++;
if (rh->stream_id) {
log_fn(LOG_PROTOCOL_WARN, domain,
"'extend' cell received for non-zero stream. Dropping.");
return 0;
}
if (cell->command != CELL_RELAY_EARLY &&
!networkstatus_get_param(NULL,"AllowNonearlyExtend",0,0,1)) {
#define EARLY_WARNING_INTERVAL 3600
static ratelim_t early_warning_limit =
RATELIM_INIT(EARLY_WARNING_INTERVAL);
char *m;
if (cell->command == CELL_RELAY) {
++total_nonearly;
if ((m = rate_limit_log(&early_warning_limit, approx_time()))) {
double percentage = ((double)total_nonearly)/total_n_extend;
percentage *= 100;
log_fn(LOG_PROTOCOL_WARN, domain, "EXTEND cell received, "
"but not via RELAY_EARLY. Dropping.%s", m);
log_fn(LOG_PROTOCOL_WARN, domain, " (We have dropped %.02f%% of "
"all EXTEND cells for this reason)", percentage);
tor_free(m);
}
} else {
log_fn(LOG_WARN, domain,
"EXTEND cell received, in a cell with type %d! Dropping.",
cell->command);
}
return 0;
}
return circuit_extend(cell, circ);
}
case RELAY_COMMAND_EXTENDED:
case RELAY_COMMAND_EXTENDED2:
if (!layer_hint) {
log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL,
"'extended' unsupported at non-origin. Dropping.");
return 0;
}
log_debug(domain,"Got an extended cell! Yay.");
{
extended_cell_t extended_cell;
if (extended_cell_parse(&extended_cell, rh->command,
(const uint8_t*)cell->payload+RELAY_HEADER_SIZE,
rh->length)<0) {
log_warn(LD_PROTOCOL,
"Can't parse EXTENDED cell; killing circuit.");
return -END_CIRC_REASON_TORPROTOCOL;
}
if ((reason = circuit_finish_handshake(TO_ORIGIN_CIRCUIT(circ),
&extended_cell.created_cell)) < 0) {
circuit_mark_for_close(circ, -reason);
return 0; /* We don't want to cause a warning, so we mark the circuit
* here. */
}
}
if ((reason=circuit_send_next_onion_skin(TO_ORIGIN_CIRCUIT(circ)))<0) {
log_info(domain,"circuit_send_next_onion_skin() failed.");
return reason;
}
/* Total all valid bytes delivered. */
if (CIRCUIT_IS_ORIGIN(circ)) {
circuit_read_valid_data(TO_ORIGIN_CIRCUIT(circ), rh->length);
}
return 0;
case RELAY_COMMAND_TRUNCATE:
if (layer_hint) {
log_fn(LOG_PROTOCOL_WARN, LD_APP,
"'truncate' unsupported at origin. Dropping.");
return 0;
}
if (circ->n_hop) {
if (circ->n_chan)
log_warn(LD_BUG, "n_chan and n_hop set on the same circuit!");
extend_info_free(circ->n_hop);
circ->n_hop = NULL;
tor_free(circ->n_chan_create_cell);
circuit_set_state(circ, CIRCUIT_STATE_OPEN);
}
if (circ->n_chan) {
uint8_t trunc_reason = get_uint8(cell->payload + RELAY_HEADER_SIZE);
circuit_synchronize_written_or_bandwidth(circ, CIRCUIT_N_CHAN);
circuit_clear_cell_queue(circ, circ->n_chan);
channel_send_destroy(circ->n_circ_id, circ->n_chan,
trunc_reason);
circuit_set_n_circid_chan(circ, 0, NULL);
}
log_debug(LD_EXIT, "Processed 'truncate', replying.");
{
char payload[1];
payload[0] = (char)END_CIRC_REASON_REQUESTED;
relay_send_command_from_edge(0, circ, RELAY_COMMAND_TRUNCATED,
payload, sizeof(payload), NULL);
}
return 0;
case RELAY_COMMAND_TRUNCATED:
if (!layer_hint) {
log_fn(LOG_PROTOCOL_WARN, LD_EXIT,
"'truncated' unsupported at non-origin. Dropping.");
return 0;
}
/* Count the truncated as valid, for completeness. The
* circuit is being torn down anyway, though. */
if (CIRCUIT_IS_ORIGIN(circ)) {
circuit_read_valid_data(TO_ORIGIN_CIRCUIT(circ),
rh->length);
}
circuit_truncated(TO_ORIGIN_CIRCUIT(circ),
get_uint8(cell->payload + RELAY_HEADER_SIZE));
return 0;
case RELAY_COMMAND_CONNECTED:
if (conn) {
log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL,
"'connected' unsupported while open. Closing circ.");
return -END_CIRC_REASON_TORPROTOCOL;
}
if (CIRCUIT_IS_ORIGIN(circ)) {
origin_circuit_t *ocirc = TO_ORIGIN_CIRCUIT(circ);
if (connection_half_edge_is_valid_connected(ocirc->half_streams,
rh->stream_id)) {
circuit_read_valid_data(ocirc, rh->length);
log_info(domain,
"connected cell on circ %u valid on half-closed "
"stream id %d", ocirc->global_identifier, rh->stream_id);
return 0;
}
}
log_info(domain,
"'connected' received on circid %u for streamid %d, "
"no conn attached anymore. Ignoring.",
(unsigned)circ->n_circ_id, rh->stream_id);
return 0;
case RELAY_COMMAND_SENDME:
return process_sendme_cell(rh, cell, circ, conn, layer_hint, domain);
case RELAY_COMMAND_RESOLVE:
if (layer_hint) {
log_fn(LOG_PROTOCOL_WARN, LD_APP,
"resolve request unsupported at AP; dropping.");
return 0;
} else if (conn) {
log_fn(LOG_PROTOCOL_WARN, domain,
"resolve request for known stream; dropping.");
return 0;
} else if (circ->purpose != CIRCUIT_PURPOSE_OR) {
log_fn(LOG_PROTOCOL_WARN, domain,
"resolve request on circ with purpose %d; dropping",
circ->purpose);
return 0;
}
connection_exit_begin_resolve(cell, TO_OR_CIRCUIT(circ));
return 0;
case RELAY_COMMAND_RESOLVED:
if (conn) {
log_fn(LOG_PROTOCOL_WARN, domain,
"'resolved' unsupported while open. Closing circ.");
return -END_CIRC_REASON_TORPROTOCOL;
}
if (CIRCUIT_IS_ORIGIN(circ)) {
origin_circuit_t *ocirc = TO_ORIGIN_CIRCUIT(circ);
if (connection_half_edge_is_valid_resolved(ocirc->half_streams,
rh->stream_id)) {
circuit_read_valid_data(ocirc, rh->length);
log_info(domain,
"resolved cell on circ %u valid on half-closed "
"stream id %d", ocirc->global_identifier, rh->stream_id);
return 0;
}
}
log_info(domain,
"'resolved' received, no conn attached anymore. Ignoring.");
return 0;
case RELAY_COMMAND_ESTABLISH_INTRO:
case RELAY_COMMAND_ESTABLISH_RENDEZVOUS:
case RELAY_COMMAND_INTRODUCE1:
case RELAY_COMMAND_INTRODUCE2:
case RELAY_COMMAND_INTRODUCE_ACK:
case RELAY_COMMAND_RENDEZVOUS1:
case RELAY_COMMAND_RENDEZVOUS2:
case RELAY_COMMAND_INTRO_ESTABLISHED:
case RELAY_COMMAND_RENDEZVOUS_ESTABLISHED:
rend_process_relay_cell(circ, layer_hint,
rh->command, rh->length,
cell->payload+RELAY_HEADER_SIZE);
return 0;
}
log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL,
"Received unknown relay command %d. Perhaps the other side is using "
"a newer version of Tor? Dropping.",
rh->command);
return 0; /* for forward compatibility, don't kill the circuit */
}
/** An incoming relay cell has arrived on circuit <b>circ</b>. If
* <b>conn</b> is NULL this is a control cell, else <b>cell</b> is
* destined for <b>conn</b>.
@ -1593,7 +1990,6 @@ connection_edge_process_relay_cell(cell_t *cell, circuit_t *circ,
static int num_seen=0;
relay_header_t rh;
unsigned domain = layer_hint?LD_APP:LD_EXIT;
int reason;
int optimistic_data = 0; /* Set to 1 if we receive data on a stream
* that's in the EXIT_CONN_STATE_RESOLVING
* or EXIT_CONN_STATE_CONNECTING states. */
@ -1652,381 +2048,8 @@ connection_edge_process_relay_cell(cell_t *cell, circuit_t *circ,
}
}
switch (rh.command) {
case RELAY_COMMAND_DROP:
/* Already examined in circpad_deliver_recognized_relay_cell_events */
return 0;
case RELAY_COMMAND_PADDING_NEGOTIATE:
circpad_handle_padding_negotiate(circ, cell);
return 0;
case RELAY_COMMAND_PADDING_NEGOTIATED:
if (circpad_handle_padding_negotiated(circ, cell, layer_hint) == 0)
circuit_read_valid_data(TO_ORIGIN_CIRCUIT(circ), rh.length);
return 0;
}
/* If this is a padding circuit we don't need to parse any other commands
* than the padding ones. Just drop them to the floor. */
if (circ->purpose == CIRCUIT_PURPOSE_C_CIRCUIT_PADDING) {
log_info(domain, "Ignored cell (%d) that arrived in padding circuit.",
rh.command);
return 0;
}
switch (rh.command) {
case RELAY_COMMAND_BEGIN:
case RELAY_COMMAND_BEGIN_DIR:
if (layer_hint &&
circ->purpose != CIRCUIT_PURPOSE_S_REND_JOINED) {
log_fn(LOG_PROTOCOL_WARN, LD_APP,
"Relay begin request unsupported at AP. Dropping.");
return 0;
}
if (circ->purpose == CIRCUIT_PURPOSE_S_REND_JOINED &&
layer_hint != TO_ORIGIN_CIRCUIT(circ)->cpath->prev) {
log_fn(LOG_PROTOCOL_WARN, LD_APP,
"Relay begin request to Hidden Service "
"from intermediary node. Dropping.");
return 0;
}
if (conn) {
log_fn(LOG_PROTOCOL_WARN, domain,
"Begin cell for known stream. Dropping.");
return 0;
}
if (rh.command == RELAY_COMMAND_BEGIN_DIR &&
circ->purpose != CIRCUIT_PURPOSE_S_REND_JOINED) {
/* Assign this circuit and its app-ward OR connection a unique ID,
* so that we can measure download times. The local edge and dir
* connection will be assigned the same ID when they are created
* and linked. */
static uint64_t next_id = 0;
circ->dirreq_id = ++next_id;
TO_OR_CIRCUIT(circ)->p_chan->dirreq_id = circ->dirreq_id;
}
return connection_exit_begin_conn(cell, circ);
case RELAY_COMMAND_DATA:
++stats_n_data_cells_received;
/* Update our circuit-level deliver window that we received a DATA cell.
* If the deliver window goes below 0, we end the circuit and stream due
* to a protocol failure. */
if (sendme_circuit_data_received(circ, layer_hint) < 0) {
log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL,
"(relay data) circ deliver_window below 0. Killing.");
connection_edge_end_close(conn, END_STREAM_REASON_TORPROTOCOL);
return -END_CIRC_REASON_TORPROTOCOL;
}
/* Consider sending a circuit-level SENDME cell. */
sendme_circuit_consider_sending(circ, layer_hint);
if (rh.stream_id == 0) {
log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, "Relay data cell with zero "
"stream_id. Dropping.");
return 0;
} else if (!conn) {
if (CIRCUIT_IS_ORIGIN(circ)) {
origin_circuit_t *ocirc = TO_ORIGIN_CIRCUIT(circ);
if (connection_half_edge_is_valid_data(ocirc->half_streams,
rh.stream_id)) {
circuit_read_valid_data(ocirc, rh.length);
log_info(domain,
"data cell on circ %u valid on half-closed "
"stream id %d", ocirc->global_identifier, rh.stream_id);
}
}
log_info(domain,"data cell dropped, unknown stream (streamid %d).",
rh.stream_id);
return 0;
}
/* Update our stream-level deliver window that we just received a DATA
* cell. Going below 0 means we have a protocol level error so the
* stream and circuit are closed. */
if (sendme_stream_data_received(conn) < 0) {
log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL,
"(relay data) conn deliver_window below 0. Killing.");
connection_edge_end_close(conn, END_STREAM_REASON_TORPROTOCOL);
return -END_CIRC_REASON_TORPROTOCOL;
}
/* Total all valid application bytes delivered */
if (CIRCUIT_IS_ORIGIN(circ) && rh.length > 0) {
circuit_read_valid_data(TO_ORIGIN_CIRCUIT(circ), rh.length);
}
stats_n_data_bytes_received += rh.length;
connection_buf_add((char*)(cell->payload + RELAY_HEADER_SIZE),
rh.length, TO_CONN(conn));
#ifdef MEASUREMENTS_21206
/* Count number of RELAY_DATA cells received on a linked directory
* connection. */
connection_t *linked_conn = TO_CONN(conn)->linked_conn;
if (linked_conn && linked_conn->type == CONN_TYPE_DIR) {
++(TO_DIR_CONN(linked_conn)->data_cells_received);
}
#endif /* defined(MEASUREMENTS_21206) */
if (!optimistic_data) {
/* Only send a SENDME if we're not getting optimistic data; otherwise
* a SENDME could arrive before the CONNECTED.
*/
sendme_connection_edge_consider_sending(conn);
}
return 0;
case RELAY_COMMAND_END:
reason = rh.length > 0 ?
get_uint8(cell->payload+RELAY_HEADER_SIZE) : END_STREAM_REASON_MISC;
if (!conn) {
if (CIRCUIT_IS_ORIGIN(circ)) {
origin_circuit_t *ocirc = TO_ORIGIN_CIRCUIT(circ);
if (connection_half_edge_is_valid_end(ocirc->half_streams,
rh.stream_id)) {
circuit_read_valid_data(ocirc, rh.length);
log_info(domain,
"end cell (%s) on circ %u valid on half-closed "
"stream id %d",
stream_end_reason_to_string(reason),
ocirc->global_identifier, rh.stream_id);
return 0;
}
}
log_info(domain,"end cell (%s) dropped, unknown stream.",
stream_end_reason_to_string(reason));
return 0;
}
/* XXX add to this log_fn the exit node's nickname? */
log_info(domain,TOR_SOCKET_T_FORMAT": end cell (%s) for stream %d. "
"Removing stream.",
conn->base_.s,
stream_end_reason_to_string(reason),
conn->stream_id);
if (conn->base_.type == CONN_TYPE_AP) {
entry_connection_t *entry_conn = EDGE_TO_ENTRY_CONN(conn);
if (entry_conn->socks_request &&
!entry_conn->socks_request->has_finished)
log_warn(LD_BUG,
"open stream hasn't sent socks answer yet? Closing.");
}
/* We just *got* an end; no reason to send one. */
conn->edge_has_sent_end = 1;
if (!conn->end_reason)
conn->end_reason = reason | END_STREAM_REASON_FLAG_REMOTE;
if (!conn->base_.marked_for_close) {
/* only mark it if not already marked. it's possible to
* get the 'end' right around when the client hangs up on us. */
connection_mark_and_flush(TO_CONN(conn));
/* Total all valid application bytes delivered */
if (CIRCUIT_IS_ORIGIN(circ)) {
circuit_read_valid_data(TO_ORIGIN_CIRCUIT(circ), rh.length);
}
}
return 0;
case RELAY_COMMAND_EXTEND:
case RELAY_COMMAND_EXTEND2: {
static uint64_t total_n_extend=0, total_nonearly=0;
total_n_extend++;
if (rh.stream_id) {
log_fn(LOG_PROTOCOL_WARN, domain,
"'extend' cell received for non-zero stream. Dropping.");
return 0;
}
if (cell->command != CELL_RELAY_EARLY &&
!networkstatus_get_param(NULL,"AllowNonearlyExtend",0,0,1)) {
#define EARLY_WARNING_INTERVAL 3600
static ratelim_t early_warning_limit =
RATELIM_INIT(EARLY_WARNING_INTERVAL);
char *m;
if (cell->command == CELL_RELAY) {
++total_nonearly;
if ((m = rate_limit_log(&early_warning_limit, approx_time()))) {
double percentage = ((double)total_nonearly)/total_n_extend;
percentage *= 100;
log_fn(LOG_PROTOCOL_WARN, domain, "EXTEND cell received, "
"but not via RELAY_EARLY. Dropping.%s", m);
log_fn(LOG_PROTOCOL_WARN, domain, " (We have dropped %.02f%% of "
"all EXTEND cells for this reason)", percentage);
tor_free(m);
}
} else {
log_fn(LOG_WARN, domain,
"EXTEND cell received, in a cell with type %d! Dropping.",
cell->command);
}
return 0;
}
return circuit_extend(cell, circ);
}
case RELAY_COMMAND_EXTENDED:
case RELAY_COMMAND_EXTENDED2:
if (!layer_hint) {
log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL,
"'extended' unsupported at non-origin. Dropping.");
return 0;
}
log_debug(domain,"Got an extended cell! Yay.");
{
extended_cell_t extended_cell;
if (extended_cell_parse(&extended_cell, rh.command,
(const uint8_t*)cell->payload+RELAY_HEADER_SIZE,
rh.length)<0) {
log_warn(LD_PROTOCOL,
"Can't parse EXTENDED cell; killing circuit.");
return -END_CIRC_REASON_TORPROTOCOL;
}
if ((reason = circuit_finish_handshake(TO_ORIGIN_CIRCUIT(circ),
&extended_cell.created_cell)) < 0) {
circuit_mark_for_close(circ, -reason);
return 0; /* We don't want to cause a warning, so we mark the circuit
* here. */
}
}
if ((reason=circuit_send_next_onion_skin(TO_ORIGIN_CIRCUIT(circ)))<0) {
log_info(domain,"circuit_send_next_onion_skin() failed.");
return reason;
}
/* Total all valid bytes delivered. */
if (CIRCUIT_IS_ORIGIN(circ)) {
circuit_read_valid_data(TO_ORIGIN_CIRCUIT(circ), rh.length);
}
return 0;
case RELAY_COMMAND_TRUNCATE:
if (layer_hint) {
log_fn(LOG_PROTOCOL_WARN, LD_APP,
"'truncate' unsupported at origin. Dropping.");
return 0;
}
if (circ->n_hop) {
if (circ->n_chan)
log_warn(LD_BUG, "n_chan and n_hop set on the same circuit!");
extend_info_free(circ->n_hop);
circ->n_hop = NULL;
tor_free(circ->n_chan_create_cell);
circuit_set_state(circ, CIRCUIT_STATE_OPEN);
}
if (circ->n_chan) {
uint8_t trunc_reason = get_uint8(cell->payload + RELAY_HEADER_SIZE);
circuit_synchronize_written_or_bandwidth(circ, CIRCUIT_N_CHAN);
circuit_clear_cell_queue(circ, circ->n_chan);
channel_send_destroy(circ->n_circ_id, circ->n_chan,
trunc_reason);
circuit_set_n_circid_chan(circ, 0, NULL);
}
log_debug(LD_EXIT, "Processed 'truncate', replying.");
{
char payload[1];
payload[0] = (char)END_CIRC_REASON_REQUESTED;
relay_send_command_from_edge(0, circ, RELAY_COMMAND_TRUNCATED,
payload, sizeof(payload), NULL);
}
return 0;
case RELAY_COMMAND_TRUNCATED:
if (!layer_hint) {
log_fn(LOG_PROTOCOL_WARN, LD_EXIT,
"'truncated' unsupported at non-origin. Dropping.");
return 0;
}
/* Count the truncated as valid, for completeness. The
* circuit is being torn down anyway, though. */
if (CIRCUIT_IS_ORIGIN(circ)) {
circuit_read_valid_data(TO_ORIGIN_CIRCUIT(circ),
rh.length);
}
circuit_truncated(TO_ORIGIN_CIRCUIT(circ),
get_uint8(cell->payload + RELAY_HEADER_SIZE));
return 0;
case RELAY_COMMAND_CONNECTED:
if (conn) {
log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL,
"'connected' unsupported while open. Closing circ.");
return -END_CIRC_REASON_TORPROTOCOL;
}
if (CIRCUIT_IS_ORIGIN(circ)) {
origin_circuit_t *ocirc = TO_ORIGIN_CIRCUIT(circ);
if (connection_half_edge_is_valid_connected(ocirc->half_streams,
rh.stream_id)) {
circuit_read_valid_data(ocirc, rh.length);
log_info(domain,
"connected cell on circ %u valid on half-closed "
"stream id %d", ocirc->global_identifier, rh.stream_id);
return 0;
}
}
log_info(domain,
"'connected' received on circid %u for streamid %d, "
"no conn attached anymore. Ignoring.",
(unsigned)circ->n_circ_id, rh.stream_id);
return 0;
case RELAY_COMMAND_SENDME:
return process_sendme_cell(&rh, cell, circ, conn, layer_hint, domain);
case RELAY_COMMAND_RESOLVE:
if (layer_hint) {
log_fn(LOG_PROTOCOL_WARN, LD_APP,
"resolve request unsupported at AP; dropping.");
return 0;
} else if (conn) {
log_fn(LOG_PROTOCOL_WARN, domain,
"resolve request for known stream; dropping.");
return 0;
} else if (circ->purpose != CIRCUIT_PURPOSE_OR) {
log_fn(LOG_PROTOCOL_WARN, domain,
"resolve request on circ with purpose %d; dropping",
circ->purpose);
return 0;
}
connection_exit_begin_resolve(cell, TO_OR_CIRCUIT(circ));
return 0;
case RELAY_COMMAND_RESOLVED:
if (conn) {
log_fn(LOG_PROTOCOL_WARN, domain,
"'resolved' unsupported while open. Closing circ.");
return -END_CIRC_REASON_TORPROTOCOL;
}
if (CIRCUIT_IS_ORIGIN(circ)) {
origin_circuit_t *ocirc = TO_ORIGIN_CIRCUIT(circ);
if (connection_half_edge_is_valid_resolved(ocirc->half_streams,
rh.stream_id)) {
circuit_read_valid_data(ocirc, rh.length);
log_info(domain,
"resolved cell on circ %u valid on half-closed "
"stream id %d", ocirc->global_identifier, rh.stream_id);
return 0;
}
}
log_info(domain,
"'resolved' received, no conn attached anymore. Ignoring.");
return 0;
case RELAY_COMMAND_ESTABLISH_INTRO:
case RELAY_COMMAND_ESTABLISH_RENDEZVOUS:
case RELAY_COMMAND_INTRODUCE1:
case RELAY_COMMAND_INTRODUCE2:
case RELAY_COMMAND_INTRODUCE_ACK:
case RELAY_COMMAND_RENDEZVOUS1:
case RELAY_COMMAND_RENDEZVOUS2:
case RELAY_COMMAND_INTRO_ESTABLISHED:
case RELAY_COMMAND_RENDEZVOUS_ESTABLISHED:
rend_process_relay_cell(circ, layer_hint,
rh.command, rh.length,
cell->payload+RELAY_HEADER_SIZE);
return 0;
}
log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL,
"Received unknown relay command %d. Perhaps the other side is using "
"a newer version of Tor? Dropping.",
rh.command);
return 0; /* for forward compatibility, don't kill the circuit */
return handle_relay_command(cell, circ, conn, layer_hint,
&rh, optimistic_data);
}
/** How many relay_data cells have we built, ever? */