commit 519c971f6a3b89f1e81cda3c0290d4d943ec0d78 Author: Andrea Shepard <andrea@persephoneslair.org> Date: Thu Aug 23 19:30:49 2012 -0700 Use channel_t in cmd.c --- src/or/command.c | 1046 ++++++------------------------------------------------ src/or/command.h | 8 +- 2 files changed, 107 insertions(+), 947 deletions(-) diff --git a/src/or/command.c b/src/or/command.c index a5ae239..c7a1b1a 100644 --- a/src/or/command.c +++ b/src/or/command.c @@ -12,10 +12,13 @@ /* In-points to command.c: * * - command_process_cell(), called from - * connection_or_process_cells_from_inbuf() in connection_or.c + * incoming cell handlers of channel_t instances; + * callbacks registered in command_setup_channel(), + * called when channels are created in circuitbuild.c */ #include "or.h" +#include "channel.h" #include "circuitbuild.h" #include "circuitlist.h" #include "command.h" @@ -31,8 +34,6 @@ #include "router.h" #include "routerlist.h" -/** How many CELL_PADDING cells have we received, ever? */ -uint64_t stats_n_padding_cells_processed = 0; /** How many CELL_CREATE cells have we received, ever? */ uint64_t stats_n_create_cells_processed = 0; /** How many CELL_CREATED cells have we received, ever? */ @@ -41,38 +42,16 @@ uint64_t stats_n_created_cells_processed = 0; uint64_t stats_n_relay_cells_processed = 0; /** How many CELL_DESTROY cells have we received, ever? */ uint64_t stats_n_destroy_cells_processed = 0; -/** How many CELL_VERSIONS cells have we received, ever? */ -uint64_t stats_n_versions_cells_processed = 0; -/** How many CELL_NETINFO cells have we received, ever? */ -uint64_t stats_n_netinfo_cells_processed = 0; -/** How many CELL_VPADDING cells have we received, ever? */ -uint64_t stats_n_vpadding_cells_processed = 0; -/** How many CELL_CERTS cells have we received, ever? */ -uint64_t stats_n_certs_cells_processed = 0; -/** How many CELL_AUTH_CHALLENGE cells have we received, ever? */ -uint64_t stats_n_auth_challenge_cells_processed = 0; -/** How many CELL_AUTHENTICATE cells have we received, ever? */ -uint64_t stats_n_authenticate_cells_processed = 0; -/** How many CELL_AUTHORIZE cells have we received, ever? */ -uint64_t stats_n_authorize_cells_processed = 0; +/* Handle an incoming channel */ +static void command_handle_incoming_channel(channel_t *listener, + channel_t *chan); /* These are the main functions for processing cells */ -static void command_process_create_cell(cell_t *cell, or_connection_t *conn); -static void command_process_created_cell(cell_t *cell, or_connection_t *conn); -static void command_process_relay_cell(cell_t *cell, or_connection_t *conn); -static void command_process_destroy_cell(cell_t *cell, or_connection_t *conn); -static void command_process_versions_cell(var_cell_t *cell, - or_connection_t *conn); -static void command_process_netinfo_cell(cell_t *cell, or_connection_t *conn); -static void command_process_certs_cell(var_cell_t *cell, - or_connection_t *conn); -static void command_process_auth_challenge_cell(var_cell_t *cell, - or_connection_t *conn); -static void command_process_authenticate_cell(var_cell_t *cell, - or_connection_t *conn); -static int enter_v3_handshake_with_cell(var_cell_t *cell, - or_connection_t *conn); +static void command_process_create_cell(cell_t *cell, channel_t *chan); +static void command_process_created_cell(cell_t *cell, channel_t *chan); +static void command_process_relay_cell(cell_t *cell, channel_t *chan); +static void command_process_destroy_cell(cell_t *cell, channel_t *chan); #ifdef KEEP_TIMING_STATS /** This is a wrapper function around the actual function that processes the @@ -80,15 +59,15 @@ static int enter_v3_handshake_with_cell(var_cell_t *cell, * by the number of microseconds used by the call to <b>*func(cell, conn)</b>. */ static void -command_time_process_cell(cell_t *cell, or_connection_t *conn, int *time, - void (*func)(cell_t *, or_connection_t *)) +command_time_process_cell(cell_t *cell, channel_t *chan, int *time, + void (*func)(cell_t *, channel_t *)) { struct timeval start, end; long time_passed; tor_gettimeofday(&start); - (*func)(cell, conn); + (*func)(cell, chan); tor_gettimeofday(&end); time_passed = tv_udiff(&start, &end) ; @@ -104,15 +83,14 @@ command_time_process_cell(cell_t *cell, or_connection_t *conn, int *time, } #endif -/** Process a <b>cell</b> that was just received on <b>conn</b>. Keep internal +/** Process a <b>cell</b> that was just received on <b>chan</b>. Keep internal * statistics about how many of each cell we've processed so far * this second, and the total number of microseconds it took to * process each type of cell. */ void -command_process_cell(cell_t *cell, or_connection_t *conn) +command_process_cell(channel_t *chan, cell_t *cell) { - int handshaking = (conn->_base.state != OR_CONN_STATE_OPEN); #ifdef KEEP_TIMING_STATS /* how many of each cell have we seen so far this second? needs better * name. */ @@ -152,255 +130,114 @@ command_process_cell(cell_t *cell, or_connection_t *conn) #define PROCESS_CELL(tp, cl, cn) command_process_ ## tp ## _cell(cl, cn) #endif - if (conn->_base.marked_for_close) - return; - - /* Reject all but VERSIONS and NETINFO when handshaking. */ - /* (VERSIONS should actually be impossible; it's variable-length.) */ - if (handshaking && cell->command != CELL_VERSIONS && - cell->command != CELL_NETINFO) { - log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, - "Received unexpected cell command %d in state %s; closing the " - "connection.", - (int)cell->command, - conn_state_to_string(CONN_TYPE_OR,conn->_base.state)); - connection_mark_for_close(TO_CONN(conn)); - return; - } - - if (conn->_base.state == OR_CONN_STATE_OR_HANDSHAKING_V3) - or_handshake_state_record_cell(conn->handshake_state, cell, 1); - switch (cell->command) { - case CELL_PADDING: - ++stats_n_padding_cells_processed; - /* do nothing */ - break; case CELL_CREATE: case CELL_CREATE_FAST: ++stats_n_create_cells_processed; - PROCESS_CELL(create, cell, conn); + PROCESS_CELL(create, cell, chan); break; case CELL_CREATED: case CELL_CREATED_FAST: ++stats_n_created_cells_processed; - PROCESS_CELL(created, cell, conn); + PROCESS_CELL(created, cell, chan); break; case CELL_RELAY: case CELL_RELAY_EARLY: ++stats_n_relay_cells_processed; - PROCESS_CELL(relay, cell, conn); + PROCESS_CELL(relay, cell, chan); break; case CELL_DESTROY: ++stats_n_destroy_cells_processed; - PROCESS_CELL(destroy, cell, conn); - break; - case CELL_VERSIONS: - tor_fragile_assert(); - break; - case CELL_NETINFO: - ++stats_n_netinfo_cells_processed; - PROCESS_CELL(netinfo, cell, conn); + PROCESS_CELL(destroy, cell, chan); break; default: log_fn(LOG_INFO, LD_PROTOCOL, - "Cell of unknown type (%d) received. Dropping.", cell->command); + "Cell of unknown or unexpected type (%d) received. " + "Dropping.", + cell->command); break; } } -/** Return true if <b>command</b> is a cell command that's allowed to start a - * V3 handshake. */ -static int -command_allowed_before_handshake(uint8_t command) -{ - switch (command) { - case CELL_VERSIONS: - case CELL_VPADDING: - case CELL_AUTHORIZE: - return 1; - default: - return 0; - } -} - -/** Process a <b>cell</b> that was just received on <b>conn</b>. Keep internal - * statistics about how many of each cell we've processed so far - * this second, and the total number of microseconds it took to - * process each type of cell. +/** Process an incoming var_cell from a channel; in the current protocol all + * the var_cells are handshake-related and handles below the channel layer, + * so this just logs a warning and drops the cell. */ + void -command_process_var_cell(var_cell_t *cell, or_connection_t *conn) +command_process_var_cell(channel_t *chan, var_cell_t *var_cell) { -#ifdef KEEP_TIMING_STATS - /* how many of each cell have we seen so far this second? needs better - * name. */ - static int num_versions=0, num_certs=0; - - time_t now = time(NULL); - - if (now > current_second) { /* the second has rolled over */ - /* print stats */ - log_info(LD_OR, - "At end of second: %d versions (%d ms), %d certs (%d ms)", - num_versions, versions_time/1000, - num_certs, certs_time/1000); - - num_versions = num_certs = 0; - versions_time = certs_time = 0; + tor_assert(chan); + tor_assert(var_cell); - /* remember which second it is, for next time */ - current_second = now; - } -#endif - - if (conn->_base.marked_for_close) - return; - - switch (conn->_base.state) - { - case OR_CONN_STATE_OR_HANDSHAKING_V2: - if (cell->command != CELL_VERSIONS) { - log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, - "Received a cell with command %d in state %s; " - "closing the connection.", - (int)cell->command, - conn_state_to_string(CONN_TYPE_OR,conn->_base.state)); - connection_mark_for_close(TO_CONN(conn)); - return; - } - break; - case OR_CONN_STATE_TLS_HANDSHAKING: - /* If we're using bufferevents, it's entirely possible for us to - * notice "hey, data arrived!" before we notice "hey, the handshake - * finished!" And we need to be accepting both at once to handle both - * the v2 and v3 handshakes. */ - - /* fall through */ - case OR_CONN_STATE_TLS_SERVER_RENEGOTIATING: - if (! command_allowed_before_handshake(cell->command)) { - log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, - "Received a cell with command %d in state %s; " - "closing the connection.", - (int)cell->command, - conn_state_to_string(CONN_TYPE_OR,conn->_base.state)); - connection_mark_for_close(TO_CONN(conn)); - return; - } else { - if (enter_v3_handshake_with_cell(cell, conn)<0) - return; - } - break; - case OR_CONN_STATE_OR_HANDSHAKING_V3: - if (cell->command != CELL_AUTHENTICATE) - or_handshake_state_record_var_cell(conn->handshake_state, cell, 1); - break; /* Everything is allowed */ - case OR_CONN_STATE_OPEN: - if (conn->link_proto < 3) { - log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, - "Received a variable-length cell with command %d in state %s " - "with link protocol %d; ignoring it.", - (int)cell->command, - conn_state_to_string(CONN_TYPE_OR,conn->_base.state), - (int)conn->link_proto); - return; - } - break; - default: - log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, - "Received var-length cell with command %d in unexpected state " - "%s [%d]; ignoring it.", - (int)cell->command, - conn_state_to_string(CONN_TYPE_OR,conn->_base.state), - (int)conn->_base.state); - return; - } - - switch (cell->command) { - case CELL_VERSIONS: - ++stats_n_versions_cells_processed; - PROCESS_CELL(versions, cell, conn); - break; - case CELL_VPADDING: - ++stats_n_vpadding_cells_processed; - /* Do nothing */ - break; - case CELL_CERTS: - ++stats_n_certs_cells_processed; - PROCESS_CELL(certs, cell, conn); - break; - case CELL_AUTH_CHALLENGE: - ++stats_n_auth_challenge_cells_processed; - PROCESS_CELL(auth_challenge, cell, conn); - break; - case CELL_AUTHENTICATE: - ++stats_n_authenticate_cells_processed; - PROCESS_CELL(authenticate, cell, conn); - break; - case CELL_AUTHORIZE: - ++stats_n_authorize_cells_processed; - /* Ignored so far. */ - break; - default: - log_fn(LOG_INFO, LD_PROTOCOL, - "Variable-length cell of unknown type (%d) received.", - cell->command); - break; - } + log_info(LD_PROTOCOL, + "Received unexpected var_cell above the channel layer of type %d" + "; dropping it.", + var_cell->command); } -/** Process a 'create' <b>cell</b> that just arrived from <b>conn</b>. Make a +/** Process a 'create' <b>cell</b> that just arrived from <b>chan</b>. Make a * new circuit with the p_circ_id specified in cell. Put the circuit in state * onionskin_pending, and pass the onionskin to the cpuworker. Circ will get * picked up again when the cpuworker finishes decrypting it. */ static void -command_process_create_cell(cell_t *cell, or_connection_t *conn) +command_process_create_cell(cell_t *cell, channel_t *chan) { or_circuit_t *circ; const or_options_t *options = get_options(); int id_is_high; + tor_assert(cell); + tor_assert(chan); + tor_assert(!(chan->is_listener)); + + log_debug(LD_OR, + "Got a CREATE cell for circ_id %d on channel %lu (%p)", + cell->circ_id, chan->global_identifier, chan); + if (we_are_hibernating()) { log_info(LD_OR, "Received create cell but we're shutting down. Sending back " "destroy."); - connection_or_send_destroy(cell->circ_id, conn, + channel_send_destroy(cell->circ_id, chan, END_CIRC_REASON_HIBERNATING); return; } if (!server_mode(options) || - (!public_server_mode(options) && conn->is_outgoing)) { + (!public_server_mode(options) && channel_is_outgoing(chan))) { log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, - "Received create cell (type %d) from %s:%d, but we're connected " + "Received create cell (type %d) from %s, but we're connected " "to it as a client. " "Sending back a destroy.", - (int)cell->command, conn->_base.address, conn->_base.port); - connection_or_send_destroy(cell->circ_id, conn, - END_CIRC_REASON_TORPROTOCOL); + (int)cell->command, channel_get_canonical_remote_descr(chan)); + channel_send_destroy(cell->circ_id, chan, + END_CIRC_REASON_TORPROTOCOL); return; } /* If the high bit of the circuit ID is not as expected, close the * circ. */ id_is_high = cell->circ_id & (1<<15); - if ((id_is_high && conn->circ_id_type == CIRC_ID_TYPE_HIGHER) || - (!id_is_high && conn->circ_id_type == CIRC_ID_TYPE_LOWER)) { + if ((id_is_high && + chan->u.cell_chan.circ_id_type == CIRC_ID_TYPE_HIGHER) || + (!id_is_high && + chan->u.cell_chan.circ_id_type == CIRC_ID_TYPE_LOWER)) { log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, "Received create cell with unexpected circ_id %d. Closing.", cell->circ_id); - connection_or_send_destroy(cell->circ_id, conn, - END_CIRC_REASON_TORPROTOCOL); + channel_send_destroy(cell->circ_id, chan, + END_CIRC_REASON_TORPROTOCOL); return; } - if (circuit_id_in_use_on_orconn(cell->circ_id, conn)) { - const node_t *node = node_get_by_id(conn->identity_digest); + if (circuit_id_in_use_on_channel(cell->circ_id, chan)) { + const node_t *node = node_get_by_id(chan->u.cell_chan.identity_digest); log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, "Received CREATE cell (circID %d) for known circ. " "Dropping (age %d).", - cell->circ_id, (int)(time(NULL) - conn->_base.timestamp_created)); + cell->circ_id, (int)(time(NULL) - channel_when_created(chan))); if (node) { char *p = esc_for_log(node_get_platform(node)); log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, @@ -411,7 +248,7 @@ command_process_create_cell(cell_t *cell, or_connection_t *conn) return; } - circ = or_circuit_new(cell->circ_id, conn); + circ = or_circuit_new(cell->circ_id, chan); circ->_base.purpose = CIRCUIT_PURPOSE_OR; circuit_set_state(TO_CIRCUIT(circ), CIRCUIT_STATE_ONIONSKIN_PENDING); if (cell->command == CELL_CREATE) { @@ -442,7 +279,7 @@ command_process_create_cell(cell_t *cell, or_connection_t *conn) /* Make sure we never try to use the OR connection on which we * received this cell to satisfy an EXTEND request, */ - conn->is_connection_with_client = 1; + channel_mark_client(chan); if (fast_server_handshake(cell->payload, (uint8_t*)reply, (uint8_t*)keys, sizeof(keys))<0) { @@ -458,7 +295,7 @@ command_process_create_cell(cell_t *cell, or_connection_t *conn) } } -/** Process a 'created' <b>cell</b> that just arrived from <b>conn</b>. +/** Process a 'created' <b>cell</b> that just arrived from <b>chan</b>. * Find the circuit * that it's intended for. If we're not the origin of the circuit, package * the 'created' cell in an 'extended' relay cell and pass it back. If we @@ -467,11 +304,11 @@ command_process_create_cell(cell_t *cell, or_connection_t *conn) * extend to the next hop in the circuit if necessary. */ static void -command_process_created_cell(cell_t *cell, or_connection_t *conn) +command_process_created_cell(cell_t *cell, channel_t *chan) { circuit_t *circ; - circ = circuit_get_by_circid_orconn(cell->circ_id, conn); + circ = circuit_get_by_circid_channel(cell->circ_id, chan); if (!circ) { log_info(LD_OR, @@ -518,17 +355,17 @@ command_process_created_cell(cell_t *cell, or_connection_t *conn) * circuit_receive_relay_cell() for actual processing. */ static void -command_process_relay_cell(cell_t *cell, or_connection_t *conn) +command_process_relay_cell(cell_t *cell, channel_t *chan) { circuit_t *circ; int reason, direction; - circ = circuit_get_by_circid_orconn(cell->circ_id, conn); + circ = circuit_get_by_circid_channel(cell->circ_id, chan); if (!circ) { log_debug(LD_OR, - "unknown circuit %d on connection from %s:%d. Dropping.", - cell->circ_id, conn->_base.address, conn->_base.port); + "unknown circuit %d on connection from %s. Dropping.", + cell->circ_id, channel_get_canonical_remote_descr(chan)); return; } @@ -541,7 +378,7 @@ command_process_relay_cell(cell_t *cell, or_connection_t *conn) if (CIRCUIT_IS_ORIGIN(circ)) { /* if we're a relay and treating connections with recent local * traffic better, then this is one of them. */ - conn->client_used = time(NULL); + channel_timestamp_client(chan); } if (!CIRCUIT_IS_ORIGIN(circ) && @@ -562,10 +399,10 @@ command_process_relay_cell(cell_t *cell, or_connection_t *conn) or_circuit_t *or_circ = TO_OR_CIRCUIT(circ); if (or_circ->remaining_relay_early_cells == 0) { log_fn(LOG_PROTOCOL_WARN, LD_OR, - "Received too many RELAY_EARLY cells on circ %d from %s:%d." + "Received too many RELAY_EARLY cells on circ %d from %s." " Closing circuit.", - cell->circ_id, safe_str(conn->_base.address), - conn->_base.port); + cell->circ_id, + safe_str(channel_get_canonical_remote_descr(chan))); circuit_mark_for_close(circ, END_CIRC_REASON_TORPROTOCOL); return; } @@ -582,7 +419,7 @@ command_process_relay_cell(cell_t *cell, or_connection_t *conn) } /** Process a 'destroy' <b>cell</b> that just arrived from - * <b>conn</b>. Find the circ that it refers to (if any). + * <b>chan</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 @@ -595,15 +432,15 @@ command_process_relay_cell(cell_t *cell, or_connection_t *conn) * and passes the destroy cell onward if necessary). */ static void -command_process_destroy_cell(cell_t *cell, or_connection_t *conn) +command_process_destroy_cell(cell_t *cell, channel_t *chan) { circuit_t *circ; int reason; - circ = circuit_get_by_circid_orconn(cell->circ_id, conn); + circ = circuit_get_by_circid_channel(cell->circ_id, chan); if (!circ) { - log_info(LD_OR,"unknown circuit %d on connection from %s:%d. Dropping.", - cell->circ_id, conn->_base.address, conn->_base.port); + log_info(LD_OR,"unknown circuit %d on connection from %s. Dropping.", + cell->circ_id, channel_get_canonical_remote_descr(chan)); return; } log_debug(LD_OR,"Received for circID %d.",cell->circ_id); @@ -613,10 +450,10 @@ command_process_destroy_cell(cell_t *cell, or_connection_t *conn) 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_set_p_circid_chan(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); + circuit_set_n_circid_chan(circ, 0, NULL); if (CIRCUIT_IS_ORIGIN(circ)) { circuit_mark_for_close(circ, reason|END_CIRC_REASON_FLAG_REMOTE); } else { @@ -629,724 +466,43 @@ command_process_destroy_cell(cell_t *cell, or_connection_t *conn) } } -/** Called when we as a server receive an appropriate cell while waiting - * either for a cell or a TLS handshake. Set the connection's state to - * "handshaking_v3', initializes the or_handshake_state field as needed, - * and add the cell to the hash of incoming cells.) - * - * Return 0 on success; return -1 and mark the connection on failure. +/** Callback to handle a new channel; call command_setup_channel() to give + * it the right cell handlers. */ -static int -enter_v3_handshake_with_cell(var_cell_t *cell, or_connection_t *conn) -{ - const int started_here = connection_or_nonopen_was_started_here(conn); - tor_assert(conn->_base.state == OR_CONN_STATE_TLS_HANDSHAKING || - conn->_base.state == OR_CONN_STATE_TLS_SERVER_RENEGOTIATING); - - if (started_here) { - log_fn(LOG_PROTOCOL_WARN, LD_OR, - "Received a cell while TLS-handshaking, not in " - "OR_HANDSHAKING_V3, on a connection we originated."); - } - conn->_base.state = OR_CONN_STATE_OR_HANDSHAKING_V3; - if (connection_init_or_handshake_state(conn, started_here) < 0) { - connection_mark_for_close(TO_CONN(conn)); - return -1; - } - or_handshake_state_record_var_cell(conn->handshake_state, cell, 1); - return 0; -} - -/** Process a 'versions' cell. The current link protocol version must be 0 - * to indicate that no version has yet been negotiated. We compare the - * versions in the cell to the list of versions we support, pick the - * highest version we have in common, and continue the negotiation from - * there. - */ static void -command_process_versions_cell(var_cell_t *cell, or_connection_t *conn) +command_handle_incoming_channel(channel_t *listener, channel_t *chan) { - int highest_supported_version = 0; - const uint8_t *cp, *end; - const int started_here = connection_or_nonopen_was_started_here(conn); - if (conn->link_proto != 0 || - (conn->handshake_state && conn->handshake_state->received_versions)) { - log_fn(LOG_PROTOCOL_WARN, LD_OR, - "Received a VERSIONS cell on a connection with its version " - "already set to %d; dropping", (int) conn->link_proto); - return; - } - switch (conn->_base.state) - { - case OR_CONN_STATE_OR_HANDSHAKING_V2: - case OR_CONN_STATE_OR_HANDSHAKING_V3: - break; - case OR_CONN_STATE_TLS_HANDSHAKING: - case OR_CONN_STATE_TLS_SERVER_RENEGOTIATING: - default: - log_fn(LOG_PROTOCOL_WARN, LD_OR, - "VERSIONS cell while in unexpected state"); - return; - } - - tor_assert(conn->handshake_state); - end = cell->payload + cell->payload_len; - for (cp = cell->payload; cp+1 < end; ++cp) { - uint16_t v = ntohs(get_uint16(cp)); - if (is_or_protocol_version_known(v) && v > highest_supported_version) - highest_supported_version = v; - } - if (!highest_supported_version) { - log_fn(LOG_PROTOCOL_WARN, LD_OR, - "Couldn't find a version in common between my version list and the " - "list in the VERSIONS cell; closing connection."); - connection_mark_for_close(TO_CONN(conn)); - return; - } else if (highest_supported_version == 1) { - /* Negotiating version 1 makes no sense, since version 1 has no VERSIONS - * cells. */ - log_fn(LOG_PROTOCOL_WARN, LD_OR, - "Used version negotiation protocol to negotiate a v1 connection. " - "That's crazily non-compliant. Closing connection."); - connection_mark_for_close(TO_CONN(conn)); - return; - } else if (highest_supported_version < 3 && - conn->_base.state == OR_CONN_STATE_OR_HANDSHAKING_V3) { - log_fn(LOG_PROTOCOL_WARN, LD_OR, - "Negotiated link protocol 2 or lower after doing a v3 TLS " - "handshake. Closing connection."); - connection_mark_for_close(TO_CONN(conn)); - return; - } - - conn->link_proto = highest_supported_version; - conn->handshake_state->received_versions = 1; - - if (conn->link_proto == 2) { - log_info(LD_OR, "Negotiated version %d with %s:%d; sending NETINFO.", - highest_supported_version, - safe_str_client(conn->_base.address), - conn->_base.port); - - if (connection_or_send_netinfo(conn) < 0) { - connection_mark_for_close(TO_CONN(conn)); - return; - } - } else { - const int send_versions = !started_here; - /* If we want to authenticate, send a CERTS cell */ - const int send_certs = !started_here || public_server_mode(get_options()); - /* If we're a relay that got a connection, ask for authentication. */ - const int send_chall = !started_here && public_server_mode(get_options()); - /* If our certs cell will authenticate us, we can send a netinfo cell - * right now. */ - const int send_netinfo = !started_here; - const int send_any = - send_versions || send_certs || send_chall || send_netinfo; - tor_assert(conn->link_proto >= 3); - - log_info(LD_OR, "Negotiated version %d with %s:%d; %s%s%s%s%s", - highest_supported_version, - safe_str_client(conn->_base.address), - conn->_base.port, - send_any ? "Sending cells:" : "Waiting for CERTS cell", - send_versions ? " VERSIONS" : "", - send_certs ? " CERTS" : "", - send_chall ? " AUTH_CHALLENGE" : "", - send_netinfo ? " NETINFO" : ""); - -#ifdef DISABLE_V3_LINKPROTO_SERVERSIDE - if (1) { - connection_mark_for_close(TO_CONN(conn)); - return; - } -#endif - - if (send_versions) { - if (connection_or_send_versions(conn, 1) < 0) { - log_warn(LD_OR, "Couldn't send versions cell"); - connection_mark_for_close(TO_CONN(conn)); - return; - } - } - if (send_certs) { - if (connection_or_send_certs_cell(conn) < 0) { - log_warn(LD_OR, "Couldn't send certs cell"); - connection_mark_for_close(TO_CONN(conn)); - return; - } - } - if (send_chall) { - if (connection_or_send_auth_challenge_cell(conn) < 0) { - log_warn(LD_OR, "Couldn't send auth_challenge cell"); - connection_mark_for_close(TO_CONN(conn)); - return; - } - } - if (send_netinfo) { - if (connection_or_send_netinfo(conn) < 0) { - log_warn(LD_OR, "Couldn't send netinfo cell"); - connection_mark_for_close(TO_CONN(conn)); - return; - } - } - } -} - -/** Process a 'netinfo' cell: read and act on its contents, and set the - * connection state to "open". */ -static void -command_process_netinfo_cell(cell_t *cell, or_connection_t *conn) -{ - time_t timestamp; - uint8_t my_addr_type; - uint8_t my_addr_len; - const uint8_t *my_addr_ptr; - const uint8_t *cp, *end; - uint8_t n_other_addrs; - time_t now = time(NULL); - - long apparent_skew = 0; - tor_addr_t my_apparent_addr = TOR_ADDR_NULL; + tor_assert(listener); + tor_assert(chan); - if (conn->link_proto < 2) { - log_fn(LOG_PROTOCOL_WARN, LD_OR, - "Received a NETINFO cell on %s connection; dropping.", - conn->link_proto == 0 ? "non-versioned" : "a v1"); - return; - } - if (conn->_base.state != OR_CONN_STATE_OR_HANDSHAKING_V2 && - conn->_base.state != OR_CONN_STATE_OR_HANDSHAKING_V3) { - log_fn(LOG_PROTOCOL_WARN, LD_OR, - "Received a NETINFO cell on non-handshaking connection; dropping."); - return; - } - tor_assert(conn->handshake_state && - conn->handshake_state->received_versions); - - if (conn->_base.state == OR_CONN_STATE_OR_HANDSHAKING_V3) { - tor_assert(conn->link_proto >= 3); - if (conn->handshake_state->started_here) { - if (!conn->handshake_state->authenticated) { - log_fn(LOG_PROTOCOL_WARN, LD_OR, "Got a NETINFO cell from server, " - "but no authentication. Closing the connection."); - connection_mark_for_close(TO_CONN(conn)); - return; - } - } else { - /* we're the server. If the client never authenticated, we have - some housekeeping to do.*/ - if (!conn->handshake_state->authenticated) { - tor_assert(tor_digest_is_zero( - (const char*)conn->handshake_state->authenticated_peer_id)); - connection_or_set_circid_type(conn, NULL); - - connection_or_init_conn_from_address(conn, - &conn->_base.addr, - conn->_base.port, - (const char*)conn->handshake_state->authenticated_peer_id, - 0); - } - } - } - - /* Decode the cell. */ - timestamp = ntohl(get_uint32(cell->payload)); - if (labs(now - conn->handshake_state->sent_versions_at) < 180) { - apparent_skew = now - timestamp; - } - - my_addr_type = (uint8_t) cell->payload[4]; - my_addr_len = (uint8_t) cell->payload[5]; - my_addr_ptr = (uint8_t*) cell->payload + 6; - end = cell->payload + CELL_PAYLOAD_SIZE; - cp = cell->payload + 6 + my_addr_len; - if (cp >= end) { - log_fn(LOG_PROTOCOL_WARN, LD_OR, - "Addresses too long in netinfo cell; closing connection."); - connection_mark_for_close(TO_CONN(conn)); - return; - } else if (my_addr_type == RESOLVED_TYPE_IPV4 && my_addr_len == 4) { - tor_addr_from_ipv4n(&my_apparent_addr, get_uint32(my_addr_ptr)); - } else if (my_addr_type == RESOLVED_TYPE_IPV6 && my_addr_len == 16) { - tor_addr_from_ipv6_bytes(&my_apparent_addr, (const char *) my_addr_ptr); - } - - n_other_addrs = (uint8_t) *cp++; - while (n_other_addrs && cp < end-2) { - /* Consider all the other addresses; if any matches, this connection is - * "canonical." */ - tor_addr_t addr; - const uint8_t *next = - decode_address_from_payload(&addr, cp, (int)(end-cp)); - if (next == NULL) { - log_fn(LOG_PROTOCOL_WARN, LD_OR, - "Bad address in netinfo cell; closing connection."); - connection_mark_for_close(TO_CONN(conn)); - return; - } - if (tor_addr_eq(&addr, &conn->real_addr)) { - conn->is_canonical = 1; - break; - } - cp = next; - --n_other_addrs; - } - - /* Act on apparent skew. */ - /** Warn when we get a netinfo skew with at least this value. */ -#define NETINFO_NOTICE_SKEW 3600 - if (labs(apparent_skew) > NETINFO_NOTICE_SKEW && - router_get_by_id_digest(conn->identity_digest)) { - char dbuf[64]; - int severity; - /*XXXX be smarter about when everybody says we are skewed. */ - if (router_digest_is_trusted_dir(conn->identity_digest)) - severity = LOG_WARN; - else - severity = LOG_INFO; - format_time_interval(dbuf, sizeof(dbuf), apparent_skew); - log_fn(severity, LD_GENERAL, "Received NETINFO cell with skewed time from " - "server at %s:%d. It seems that our clock is %s by %s, or " - "that theirs is %s. Tor requires an accurate clock to work: " - "please check your time and date settings.", - conn->_base.address, (int)conn->_base.port, - apparent_skew>0 ? "ahead" : "behind", dbuf, - apparent_skew>0 ? "behind" : "ahead"); - if (severity == LOG_WARN) /* only tell the controller if an authority */ - control_event_general_status(LOG_WARN, - "CLOCK_SKEW SKEW=%ld SOURCE=OR:%s:%d", - apparent_skew, - conn->_base.address, conn->_base.port); - } - - /* XXX maybe act on my_apparent_addr, if the source is sufficiently - * trustworthy. */ - - if (connection_or_set_state_open(conn)<0) { - log_fn(LOG_PROTOCOL_WARN, LD_OR, "Got good NETINFO cell from %s:%d; but " - "was unable to make the OR connection become open.", - safe_str_client(conn->_base.address), - conn->_base.port); - connection_mark_for_close(TO_CONN(conn)); - } else { - log_info(LD_OR, "Got good NETINFO cell from %s:%d; OR connection is now " - "open, using protocol version %d. Its ID digest is %s. " - "Our address is apparently %s.", - safe_str_client(conn->_base.address), - conn->_base.port, (int)conn->link_proto, - hex_str(conn->identity_digest, DIGEST_LEN), - tor_addr_is_null(&my_apparent_addr) ? - "<none>" : fmt_and_decorate_addr(&my_apparent_addr)); - } - assert_connection_ok(TO_CONN(conn),time(NULL)); + command_setup_channel(chan); } -/** Process a CERTS cell from an OR connection. - * - * If the other side should not have sent us a CERTS cell, or the cell is - * malformed, or it is supposed to authenticate the TLS key but it doesn't, - * then mark the connection. - * - * If the cell has a good cert chain and we're doing a v3 handshake, then - * store the certificates in or_handshake_state. If this is the client side - * of the connection, we then authenticate the server or mark the connection. - * If it's the server side, wait for an AUTHENTICATE cell. +/** Given a channel, install the right handlers to process incoming + * cells on it. */ -static void -command_process_certs_cell(var_cell_t *cell, or_connection_t *conn) -{ -#define ERR(s) \ - do { \ - log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, \ - "Received a bad CERTS cell from %s:%d: %s", \ - safe_str(conn->_base.address), conn->_base.port, (s)); \ - connection_mark_for_close(TO_CONN(conn)); \ - goto err; \ - } while (0) - - tor_cert_t *link_cert = NULL; - tor_cert_t *id_cert = NULL; - tor_cert_t *auth_cert = NULL; - - uint8_t *ptr; - int n_certs, i; - int send_netinfo = 0; - - if (conn->_base.state != OR_CONN_STATE_OR_HANDSHAKING_V3) - ERR("We're not doing a v3 handshake!"); - if (conn->link_proto < 3) - ERR("We're not using link protocol >= 3"); - if (conn->handshake_state->received_certs_cell) - ERR("We already got one"); - if (conn->handshake_state->authenticated) { - /* Should be unreachable, but let's make sure. */ - ERR("We're already authenticated!"); - } - if (cell->payload_len < 1) - ERR("It had no body"); - if (cell->circ_id) - ERR("It had a nonzero circuit ID"); - - n_certs = cell->payload[0]; - ptr = cell->payload + 1; - for (i = 0; i < n_certs; ++i) { - uint8_t cert_type; - uint16_t cert_len; - if (ptr + 3 > cell->payload + cell->payload_len) { - goto truncated; - } - cert_type = *ptr; - cert_len = ntohs(get_uint16(ptr+1)); - if (ptr + 3 + cert_len > cell->payload + cell->payload_len) { - goto truncated; - } - if (cert_type == OR_CERT_TYPE_TLS_LINK || - cert_type == OR_CERT_TYPE_ID_1024 || - cert_type == OR_CERT_TYPE_AUTH_1024) { - tor_cert_t *cert = tor_cert_decode(ptr + 3, cert_len); - if (!cert) { - log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, - "Received undecodable certificate in CERTS cell from %s:%d", - safe_str(conn->_base.address), conn->_base.port); - } else { - if (cert_type == OR_CERT_TYPE_TLS_LINK) { - if (link_cert) { - tor_cert_free(cert); - ERR("Too many TLS_LINK certificates"); - } - link_cert = cert; - } else if (cert_type == OR_CERT_TYPE_ID_1024) { - if (id_cert) { - tor_cert_free(cert); - ERR("Too many ID_1024 certificates"); - } - id_cert = cert; - } else if (cert_type == OR_CERT_TYPE_AUTH_1024) { - if (auth_cert) { - tor_cert_free(cert); - ERR("Too many AUTH_1024 certificates"); - } - auth_cert = cert; - } else { - tor_cert_free(cert); - } - } - } - ptr += 3 + cert_len; - continue; - - truncated: - ERR("It ends in the middle of a certificate"); - } - - if (conn->handshake_state->started_here) { - int severity; - if (! (id_cert && link_cert)) - ERR("The certs we wanted were missing"); - /* Okay. We should be able to check the certificates now. */ - if (! tor_tls_cert_matches_key(conn->tls, link_cert)) { - ERR("The link certificate didn't match the TLS public key"); - } - /* Note that this warns more loudly about time and validity if we were - * _trying_ to connect to an authority, not necessarily if we _did_ connect - * to one. */ - if (router_digest_is_trusted_dir(conn->identity_digest)) - severity = LOG_WARN; - else - severity = LOG_PROTOCOL_WARN; - - if (! tor_tls_cert_is_valid(severity, link_cert, id_cert, 0)) - ERR("The link certificate was not valid"); - if (! tor_tls_cert_is_valid(severity, id_cert, id_cert, 1)) - ERR("The ID certificate was not valid"); - - conn->handshake_state->authenticated = 1; - { - const digests_t *id_digests = tor_cert_get_id_digests(id_cert); - crypto_pk_t *identity_rcvd; - if (!id_digests) - ERR("Couldn't compute digests for key in ID cert"); - - identity_rcvd = tor_tls_cert_get_key(id_cert); - if (!identity_rcvd) - ERR("Internal error: Couldn't get RSA key from ID cert."); - memcpy(conn->handshake_state->authenticated_peer_id, - id_digests->d[DIGEST_SHA1], DIGEST_LEN); - connection_or_set_circid_type(conn, identity_rcvd); - crypto_pk_free(identity_rcvd); - } - - if (connection_or_client_learned_peer_id(conn, - conn->handshake_state->authenticated_peer_id) < 0) - ERR("Problem setting or checking peer id"); - - log_info(LD_OR, "Got some good certificates from %s:%d: Authenticated it.", - safe_str(conn->_base.address), conn->_base.port); - - conn->handshake_state->id_cert = id_cert; - id_cert = NULL; - - if (!public_server_mode(get_options())) { - /* If we initiated the connection and we are not a public server, we - * aren't planning to authenticate at all. At this point we know who we - * are talking to, so we can just send a netinfo now. */ - send_netinfo = 1; - } - } else { - if (! (id_cert && auth_cert)) - ERR("The certs we wanted were missing"); - - /* Remember these certificates so we can check an AUTHENTICATE cell */ - if (! tor_tls_cert_is_valid(LOG_PROTOCOL_WARN, auth_cert, id_cert, 1)) - ERR("The authentication certificate was not valid"); - if (! tor_tls_cert_is_valid(LOG_PROTOCOL_WARN, id_cert, id_cert, 1)) - ERR("The ID certificate was not valid"); - - log_info(LD_OR, "Got some good certificates from %s:%d: " - "Waiting for AUTHENTICATE.", - safe_str(conn->_base.address), conn->_base.port); - /* XXXX check more stuff? */ - conn->handshake_state->id_cert = id_cert; - conn->handshake_state->auth_cert = auth_cert; - id_cert = auth_cert = NULL; - } - - conn->handshake_state->received_certs_cell = 1; - - if (send_netinfo) { - if (connection_or_send_netinfo(conn) < 0) { - log_warn(LD_OR, "Couldn't send netinfo cell"); - connection_mark_for_close(TO_CONN(conn)); - goto err; - } - } - - err: - tor_cert_free(id_cert); - tor_cert_free(link_cert); - tor_cert_free(auth_cert); -#undef ERR -} - -/** Process an AUTH_CHALLENGE cell from an OR connection. - * - * If we weren't supposed to get one (for example, because we're not the - * originator of the connection), or it's ill-formed, or we aren't doing a v3 - * handshake, mark the connection. If the cell is well-formed but we don't - * want to authenticate, just drop it. If the cell is well-formed *and* we - * want to authenticate, send an AUTHENTICATE cell and then a NETINFO cell. */ -static void -command_process_auth_challenge_cell(var_cell_t *cell, or_connection_t *conn) +void +command_setup_channel(channel_t *chan) { - int n_types, i, use_type = -1; - uint8_t *cp; - -#define ERR(s) \ - do { \ - log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, \ - "Received a bad AUTH_CHALLENGE cell from %s:%d: %s", \ - safe_str(conn->_base.address), conn->_base.port, (s)); \ - connection_mark_for_close(TO_CONN(conn)); \ - return; \ - } while (0) - - if (conn->_base.state != OR_CONN_STATE_OR_HANDSHAKING_V3) - ERR("We're not currently doing a v3 handshake"); - if (conn->link_proto < 3) - ERR("We're not using link protocol >= 3"); - if (! conn->handshake_state->started_here) - ERR("We didn't originate this connection"); - if (conn->handshake_state->received_auth_challenge) - ERR("We already received one"); - if (! conn->handshake_state->received_certs_cell) - ERR("We haven't gotten a CERTS cell yet"); - if (cell->payload_len < OR_AUTH_CHALLENGE_LEN + 2) - ERR("It was too short"); - if (cell->circ_id) - ERR("It had a nonzero circuit ID"); - - n_types = ntohs(get_uint16(cell->payload + OR_AUTH_CHALLENGE_LEN)); - if (cell->payload_len < OR_AUTH_CHALLENGE_LEN + 2 + 2*n_types) - ERR("It looks truncated"); - - /* Now see if there is an authentication type we can use */ - cp=cell->payload+OR_AUTH_CHALLENGE_LEN+2; - for (i=0; i < n_types; ++i, cp += 2) { - uint16_t authtype = ntohs(get_uint16(cp)); - if (authtype == AUTHTYPE_RSA_SHA256_TLSSECRET) - use_type = authtype; - } - - conn->handshake_state->received_auth_challenge = 1; - - if (! public_server_mode(get_options())) { - /* If we're not a public server then we don't want to authenticate on a - connection we originated, and we already sent a NETINFO cell when we - got the CERTS cell. We have nothing more to do. */ - return; - } - - if (use_type >= 0) { - log_info(LD_OR, "Got an AUTH_CHALLENGE cell from %s:%d: Sending " - "authentication", - safe_str(conn->_base.address), conn->_base.port); - - if (connection_or_send_authenticate_cell(conn, use_type) < 0) { - log_warn(LD_OR, "Couldn't send authenticate cell"); - connection_mark_for_close(TO_CONN(conn)); - return; - } - } else { - log_info(LD_OR, "Got an AUTH_CHALLENGE cell from %s:%d, but we don't " - "know any of its authentication types. Not authenticating.", - safe_str(conn->_base.address), conn->_base.port); - } - - if (connection_or_send_netinfo(conn) < 0) { - log_warn(LD_OR, "Couldn't send netinfo cell"); - connection_mark_for_close(TO_CONN(conn)); - return; - } + tor_assert(chan); -#undef ERR + channel_set_cell_handlers(chan, + command_process_cell, + command_process_var_cell); } -/** Process an AUTHENTICATE cell from an OR connection. - * - * If it's ill-formed or we weren't supposed to get one or we're not doing a - * v3 handshake, then mark the connection. If it does not authenticate the - * other side of the connection successfully (because it isn't signed right, - * we didn't get a CERTS cell, etc) mark the connection. Otherwise, accept - * the identity of the router on the other side of the connection. +/** Given a listener, install the right handler to process incoming + * channels on it. */ -static void -command_process_authenticate_cell(var_cell_t *cell, or_connection_t *conn) -{ - uint8_t expected[V3_AUTH_FIXED_PART_LEN]; - const uint8_t *auth; - int authlen; - -#define ERR(s) \ - do { \ - log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, \ - "Received a bad AUTHENTICATE cell from %s:%d: %s", \ - safe_str(conn->_base.address), conn->_base.port, (s)); \ - connection_mark_for_close(TO_CONN(conn)); \ - return; \ - } while (0) - - if (conn->_base.state != OR_CONN_STATE_OR_HANDSHAKING_V3) - ERR("We're not doing a v3 handshake"); - if (conn->link_proto < 3) - ERR("We're not using link protocol >= 3"); - if (conn->handshake_state->started_here) - ERR("We originated this connection"); - if (conn->handshake_state->received_authenticate) - ERR("We already got one!"); - if (conn->handshake_state->authenticated) { - /* Should be impossible given other checks */ - ERR("The peer is already authenticated"); - } - if (! conn->handshake_state->received_certs_cell) - ERR("We never got a certs cell"); - if (conn->handshake_state->auth_cert == NULL) - ERR("We never got an authentication certificate"); - if (conn->handshake_state->id_cert == NULL) - ERR("We never got an identity certificate"); - if (cell->payload_len < 4) - ERR("Cell was way too short"); - - auth = cell->payload; - { - uint16_t type = ntohs(get_uint16(auth)); - uint16_t len = ntohs(get_uint16(auth+2)); - if (4 + len > cell->payload_len) - ERR("Authenticator was truncated"); - - if (type != AUTHTYPE_RSA_SHA256_TLSSECRET) - ERR("Authenticator type was not recognized"); - - auth += 4; - authlen = len; - } - - if (authlen < V3_AUTH_BODY_LEN + 1) - ERR("Authenticator was too short"); - - if (connection_or_compute_authenticate_cell_body( - conn, expected, sizeof(expected), NULL, 1) < 0) - ERR("Couldn't compute expected AUTHENTICATE cell body"); - - if (tor_memneq(expected, auth, sizeof(expected))) - ERR("Some field in the AUTHENTICATE cell body was not as expected"); - - { - crypto_pk_t *pk = tor_tls_cert_get_key( - conn->handshake_state->auth_cert); - char d[DIGEST256_LEN]; - char *signed_data; - size_t keysize; - int signed_len; - if (!pk) - ERR("Internal error: couldn't get RSA key from AUTH cert."); - crypto_digest256(d, (char*)auth, V3_AUTH_BODY_LEN, DIGEST_SHA256); - - keysize = crypto_pk_keysize(pk); - signed_data = tor_malloc(keysize); - signed_len = crypto_pk_public_checksig(pk, signed_data, keysize, - (char*)auth + V3_AUTH_BODY_LEN, - authlen - V3_AUTH_BODY_LEN); - crypto_pk_free(pk); - if (signed_len < 0) { - tor_free(signed_data); - ERR("Signature wasn't valid"); - } - if (signed_len < DIGEST256_LEN) { - tor_free(signed_data); - ERR("Not enough data was signed"); - } - /* Note that we deliberately allow *more* than DIGEST256_LEN bytes here, - * in case they're later used to hold a SHA3 digest or something. */ - if (tor_memneq(signed_data, d, DIGEST256_LEN)) { - tor_free(signed_data); - ERR("Signature did not match data to be signed."); - } - tor_free(signed_data); - } - - /* Okay, we are authenticated. */ - conn->handshake_state->received_authenticate = 1; - conn->handshake_state->authenticated = 1; - conn->handshake_state->digest_received_data = 0; - { - crypto_pk_t *identity_rcvd = - tor_tls_cert_get_key(conn->handshake_state->id_cert); - const digests_t *id_digests = - tor_cert_get_id_digests(conn->handshake_state->id_cert); - - /* This must exist; we checked key type when reading the cert. */ - tor_assert(id_digests); - - memcpy(conn->handshake_state->authenticated_peer_id, - id_digests->d[DIGEST_SHA1], DIGEST_LEN); - - connection_or_set_circid_type(conn, identity_rcvd); - crypto_pk_free(identity_rcvd); - - connection_or_init_conn_from_address(conn, - &conn->_base.addr, - conn->_base.port, - (const char*)conn->handshake_state->authenticated_peer_id, - 0); - - log_info(LD_OR, "Got an AUTHENTICATE cell from %s:%d: Looks good.", - safe_str(conn->_base.address), conn->_base.port); - } +void +command_setup_listener(channel_t *listener) +{ + tor_assert(listener); + tor_assert(listener->state == CHANNEL_STATE_LISTENING); -#undef ERR + channel_set_listener(listener, command_handle_incoming_channel); } diff --git a/src/or/command.h b/src/or/command.h index 078ccc9..eddce87 100644 --- a/src/or/command.h +++ b/src/or/command.h @@ -12,8 +12,12 @@ #ifndef _TOR_COMMAND_H #define _TOR_COMMAND_H -void command_process_cell(cell_t *cell, or_connection_t *conn); -void command_process_var_cell(var_cell_t *cell, or_connection_t *conn); +#include "channel.h" + +void command_process_cell(channel_t *chan, cell_t *cell); +void command_process_var_cell(channel_t *chan, var_cell_t *cell); +void command_setup_channel(channel_t *chan); +void command_setup_listener(channel_t *chan); extern uint64_t stats_n_padding_cells_processed; extern uint64_t stats_n_create_cells_processed;