commit 7a032c5e4838651b62b99938d56e94b4a6fc6197
Author: George Kadianakis <desnacked(a)riseup.net>
Date: Tue Jul 23 13:01:12 2019 +0300
Split connection_edge_process_relay_cell() in two functions.
One function does the validation, the other does the handling.
---
src/core/or/relay.c | 225 +++++++++++++++++++++++++++++-----------------------
1 file changed, 124 insertions(+), 101 deletions(-)
diff --git a/src/core/or/relay.c b/src/core/or/relay.c
index 9e691a02b..84fc58787 100644
--- a/src/core/or/relay.c
+++ b/src/core/or/relay.c
@@ -1576,83 +1576,27 @@ process_sendme_cell(const relay_header_t *rh, const cell_t *cell,
return 0;
}
-/** 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>.
- *
- * If <b>layer_hint</b> is defined, then we're the origin of the
- * circuit, and it specifies the hop that packaged <b>cell</b>.
+/** A helper for connection_edge_process_relay_cell(): Actually handles the
+ * cell that we received on the connection.
*
- * Return -reason if you want to warn and tear down the circuit, else 0.
+ * 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
-connection_edge_process_relay_cell(cell_t *cell, circuit_t *circ,
- edge_connection_t *conn,
- crypt_path_t *layer_hint)
+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)
{
- 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. */
-
- tor_assert(cell);
- tor_assert(circ);
-
- relay_header_unpack(&rh, cell->payload);
-// log_fn(LOG_DEBUG,"command %d stream %d", rh.command, rh.stream_id);
- num_seen++;
- log_debug(domain, "Now seen %d relay cells here (command %d, stream %d).",
- num_seen, rh.command, rh.stream_id);
- if (rh.length > RELAY_PAYLOAD_SIZE) {
- log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL,
- "Relay cell length field too long. Closing circuit.");
- return - END_CIRC_REASON_TORPROTOCOL;
- }
-
- if (rh.stream_id == 0) {
- switch (rh.command) {
- case RELAY_COMMAND_BEGIN:
- case RELAY_COMMAND_CONNECTED:
- case RELAY_COMMAND_END:
- case RELAY_COMMAND_RESOLVE:
- case RELAY_COMMAND_RESOLVED:
- case RELAY_COMMAND_BEGIN_DIR:
- log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, "Relay command %d with zero "
- "stream_id. Dropping.", (int)rh.command);
- return 0;
- default:
- ;
- }
- }
-
- /* Tell circpad that we've received a recognized cell */
- circpad_deliver_recognized_relay_cell_events(circ, rh.command, layer_hint);
-
- /* either conn is NULL, in which case we've got a control cell, or else
- * conn points to the recognized stream. */
- if (conn && !connection_state_is_open(TO_CONN(conn))) {
- if (conn->base_.type == CONN_TYPE_EXIT &&
- (conn->base_.state == EXIT_CONN_STATE_CONNECTING ||
- conn->base_.state == EXIT_CONN_STATE_RESOLVING) &&
- rh.command == RELAY_COMMAND_DATA) {
- /* Allow DATA cells to be delivered to an exit node in state
- * EXIT_CONN_STATE_CONNECTING or EXIT_CONN_STATE_RESOLVING.
- * This speeds up HTTP, for example. */
- optimistic_data = 1;
- } else if (rh.stream_id == 0 && rh.command == RELAY_COMMAND_DATA) {
- log_warn(LD_BUG, "Somehow I had a connection that matched a "
- "data cell with stream ID 0.");
- } else {
- return connection_edge_process_relay_cell_not_open(
- &rh, cell, circ, conn, layer_hint);
- }
- }
+ tor_assert(rh);
- switch (rh.command) {
+ switch (rh->command) {
case RELAY_COMMAND_DROP:
/* Already examined in circpad_deliver_recognized_relay_cell_events */
return 0;
@@ -1661,7 +1605,7 @@ connection_edge_process_relay_cell(cell_t *cell, circuit_t *circ,
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);
+ circuit_read_valid_data(TO_ORIGIN_CIRCUIT(circ), rh->length);
return 0;
}
@@ -1694,7 +1638,7 @@ connection_edge_process_relay_cell(cell_t *cell, circuit_t *circ,
"Begin cell for known stream. Dropping.");
return 0;
}
- if (rh.command == RELAY_COMMAND_BEGIN_DIR &&
+ 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
@@ -1721,7 +1665,7 @@ connection_edge_process_relay_cell(cell_t *cell, circuit_t *circ,
/* Consider sending a circuit-level SENDME cell. */
sendme_circuit_consider_sending(circ, layer_hint);
- if (rh.stream_id == 0) {
+ if (rh->stream_id == 0) {
log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, "Relay data cell with zero "
"stream_id. Dropping.");
return 0;
@@ -1729,16 +1673,16 @@ connection_edge_process_relay_cell(cell_t *cell, circuit_t *circ,
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);
+ 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);
+ "stream id %d", ocirc->global_identifier, rh->stream_id);
}
}
log_info(domain,"data cell dropped, unknown stream (streamid %d).",
- rh.stream_id);
+ rh->stream_id);
return 0;
}
@@ -1753,13 +1697,13 @@ connection_edge_process_relay_cell(cell_t *cell, circuit_t *circ,
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);
+ 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;
+ stats_n_data_bytes_received += rh->length;
connection_buf_add((char*)(cell->payload + RELAY_HEADER_SIZE),
- rh.length, TO_CONN(conn));
+ rh->length, TO_CONN(conn));
#ifdef MEASUREMENTS_21206
/* Count number of RELAY_DATA cells received on a linked directory
@@ -1780,20 +1724,20 @@ connection_edge_process_relay_cell(cell_t *cell, circuit_t *circ,
return 0;
case RELAY_COMMAND_END:
- reason = rh.length > 0 ?
+ 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)) {
+ rh->stream_id)) {
- circuit_read_valid_data(ocirc, rh.length);
+ 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);
+ ocirc->global_identifier, rh->stream_id);
return 0;
}
}
@@ -1825,7 +1769,7 @@ connection_edge_process_relay_cell(cell_t *cell, circuit_t *circ,
/* Total all valid application bytes delivered */
if (CIRCUIT_IS_ORIGIN(circ)) {
- circuit_read_valid_data(TO_ORIGIN_CIRCUIT(circ), rh.length);
+ circuit_read_valid_data(TO_ORIGIN_CIRCUIT(circ), rh->length);
}
}
return 0;
@@ -1833,7 +1777,7 @@ connection_edge_process_relay_cell(cell_t *cell, circuit_t *circ,
case RELAY_COMMAND_EXTEND2: {
static uint64_t total_n_extend=0, total_nonearly=0;
total_n_extend++;
- if (rh.stream_id) {
+ if (rh->stream_id) {
log_fn(LOG_PROTOCOL_WARN, domain,
"'extend' cell received for non-zero stream. Dropping.");
return 0;
@@ -1874,9 +1818,9 @@ connection_edge_process_relay_cell(cell_t *cell, circuit_t *circ,
log_debug(domain,"Got an extended cell! Yay.");
{
extended_cell_t extended_cell;
- if (extended_cell_parse(&extended_cell, rh.command,
+ if (extended_cell_parse(&extended_cell, rh->command,
(const uint8_t*)cell->payload+RELAY_HEADER_SIZE,
- rh.length)<0) {
+ rh->length)<0) {
log_warn(LD_PROTOCOL,
"Can't parse EXTENDED cell; killing circuit.");
return -END_CIRC_REASON_TORPROTOCOL;
@@ -1894,7 +1838,7 @@ connection_edge_process_relay_cell(cell_t *cell, circuit_t *circ,
}
/* Total all valid bytes delivered. */
if (CIRCUIT_IS_ORIGIN(circ)) {
- circuit_read_valid_data(TO_ORIGIN_CIRCUIT(circ), rh.length);
+ circuit_read_valid_data(TO_ORIGIN_CIRCUIT(circ), rh->length);
}
return 0;
case RELAY_COMMAND_TRUNCATE:
@@ -1938,7 +1882,7 @@ connection_edge_process_relay_cell(cell_t *cell, circuit_t *circ,
* circuit is being torn down anyway, though. */
if (CIRCUIT_IS_ORIGIN(circ)) {
circuit_read_valid_data(TO_ORIGIN_CIRCUIT(circ),
- rh.length);
+ rh->length);
}
circuit_truncated(TO_ORIGIN_CIRCUIT(circ),
get_uint8(cell->payload + RELAY_HEADER_SIZE));
@@ -1953,11 +1897,11 @@ connection_edge_process_relay_cell(cell_t *cell, circuit_t *circ,
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);
+ 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);
+ "stream id %d", ocirc->global_identifier, rh->stream_id);
return 0;
}
}
@@ -1965,10 +1909,10 @@ connection_edge_process_relay_cell(cell_t *cell, circuit_t *circ,
log_info(domain,
"'connected' received on circid %u for streamid %d, "
"no conn attached anymore. Ignoring.",
- (unsigned)circ->n_circ_id, rh.stream_id);
+ (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);
+ 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,
@@ -1996,11 +1940,11 @@ connection_edge_process_relay_cell(cell_t *cell, circuit_t *circ,
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);
+ 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);
+ "stream id %d", ocirc->global_identifier, rh->stream_id);
return 0;
}
}
@@ -2018,17 +1962,96 @@ connection_edge_process_relay_cell(cell_t *cell, circuit_t *circ,
case RELAY_COMMAND_INTRO_ESTABLISHED:
case RELAY_COMMAND_RENDEZVOUS_ESTABLISHED:
rend_process_relay_cell(circ, layer_hint,
- rh.command, rh.length,
+ 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);
+ 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>.
+ *
+ * If <b>layer_hint</b> is defined, then we're the origin of the
+ * circuit, and it specifies the hop that packaged <b>cell</b>.
+ *
+ * Return -reason if you want to warn and tear down the circuit, else 0.
+ */
+STATIC int
+connection_edge_process_relay_cell(cell_t *cell, circuit_t *circ,
+ edge_connection_t *conn,
+ crypt_path_t *layer_hint)
+{
+ static int num_seen=0;
+ relay_header_t rh;
+ unsigned domain = layer_hint?LD_APP:LD_EXIT;
+ 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. */
+
+ tor_assert(cell);
+ tor_assert(circ);
+
+ relay_header_unpack(&rh, cell->payload);
+// log_fn(LOG_DEBUG,"command %d stream %d", rh.command, rh.stream_id);
+ num_seen++;
+ log_debug(domain, "Now seen %d relay cells here (command %d, stream %d).",
+ num_seen, rh.command, rh.stream_id);
+
+ if (rh.length > RELAY_PAYLOAD_SIZE) {
+ log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL,
+ "Relay cell length field too long. Closing circuit.");
+ return - END_CIRC_REASON_TORPROTOCOL;
+ }
+
+ if (rh.stream_id == 0) {
+ switch (rh.command) {
+ case RELAY_COMMAND_BEGIN:
+ case RELAY_COMMAND_CONNECTED:
+ case RELAY_COMMAND_END:
+ case RELAY_COMMAND_RESOLVE:
+ case RELAY_COMMAND_RESOLVED:
+ case RELAY_COMMAND_BEGIN_DIR:
+ log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, "Relay command %d with zero "
+ "stream_id. Dropping.", (int)rh.command);
+ return 0;
+ default:
+ ;
+ }
+ }
+
+ /* Tell circpad that we've received a recognized cell */
+ circpad_deliver_recognized_relay_cell_events(circ, rh.command, layer_hint);
+
+ /* either conn is NULL, in which case we've got a control cell, or else
+ * conn points to the recognized stream. */
+ if (conn && !connection_state_is_open(TO_CONN(conn))) {
+ if (conn->base_.type == CONN_TYPE_EXIT &&
+ (conn->base_.state == EXIT_CONN_STATE_CONNECTING ||
+ conn->base_.state == EXIT_CONN_STATE_RESOLVING) &&
+ rh.command == RELAY_COMMAND_DATA) {
+ /* Allow DATA cells to be delivered to an exit node in state
+ * EXIT_CONN_STATE_CONNECTING or EXIT_CONN_STATE_RESOLVING.
+ * This speeds up HTTP, for example. */
+ optimistic_data = 1;
+ } else if (rh.stream_id == 0 && rh.command == RELAY_COMMAND_DATA) {
+ log_warn(LD_BUG, "Somehow I had a connection that matched a "
+ "data cell with stream ID 0.");
+ } else {
+ return connection_edge_process_relay_cell_not_open(
+ &rh, cell, circ, conn, layer_hint);
+ }
+ }
+
+ return handle_relay_command(cell, circ, conn, layer_hint,
+ &rh, optimistic_data);
+}
+
/** How many relay_data cells have we built, ever? */
uint64_t stats_n_data_cells_packaged = 0;
/** How many bytes of data have we put in relay_data cells have we built,
