/* * FreeSWITCH Modular Media Switching Software Library / Soft-Switch Application * Copyright (C) 2005/2006, Anthony Minessale II * * Version: MPL 1.1 * * The contents of this file are subject to the Mozilla Public License Version * 1.1 (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * http://www.mozilla.org/MPL/ * * Software distributed under the License is distributed on an "AS IS" basis, * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License * for the specific language governing rights and limitations under the * License. * * The Original Code is FreeSWITCH Modular Media Switching Software Library / Soft-Switch Application * * The Initial Developer of the Original Code is * Anthony Minessale II * Portions created by the Initial Developer are Copyright (C) * the Initial Developer. All Rights Reserved. * * Contributor(s): * * Anthony Minessale II * * * switch_rtp.c -- RTP * */ #include #undef PACKAGE_NAME #undef PACKAGE_STRING #undef PACKAGE_TARNAME #undef PACKAGE_VERSION #undef PACKAGE_BUGREPORT #include #include #define MAX_KEY_LEN 64 #define rtp_header_len 12 #define RTP_START_PORT 16384 #define RTP_END_PORT 32768 #define SWITCH_RTP_CNG_PAYLOAD 13 #define MAX_KEY_LEN 64 #define MASTER_KEY_LEN 30 static switch_port_t NEXT_PORT = RTP_START_PORT; static switch_mutex_t *port_lock = NULL; typedef srtp_hdr_t rtp_hdr_t; typedef struct { srtp_hdr_t header; char body[SWITCH_RTP_MAX_BUF_LEN]; } rtp_msg_t; struct switch_rtp { switch_socket_t *sock; switch_sockaddr_t *local_addr; rtp_msg_t send_msg; srtp_ctx_t *send_ctx; switch_sockaddr_t *remote_addr; rtp_msg_t recv_msg; srtp_ctx_t *recv_ctx; uint16_t seq; uint8_t payload; switch_rtp_invalid_handler invalid_handler; void *private_data; uint32_t ts; uint32_t flags; switch_memory_pool *pool; switch_sockaddr_t *from_addr; char *ice_user; char *user_ice; switch_time_t last_stun; uint32_t packet_size; switch_time_t last_read; switch_time_t next_read; uint32_t ms_per_packet; uint8_t stuncount; switch_buffer *packet_buffer; }; static int global_init = 0; static switch_status ice_out(switch_rtp *rtp_session) { assert(rtp_session != NULL); assert(rtp_session->ice_user != NULL); if (rtp_session->stuncount == 0) { uint8_t buf[256] = {0}; switch_stun_packet_t *packet; unsigned int elapsed; switch_size_t bytes; if (rtp_session->last_stun) { elapsed = (unsigned int)((switch_time_now() - rtp_session->last_stun) / 1000); if (elapsed > 10000) { switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "No stun for a long time (PUNT!)\n"); return SWITCH_STATUS_FALSE; } } packet = switch_stun_packet_build_header(SWITCH_STUN_BINDING_REQUEST, NULL, buf); switch_stun_packet_attribute_add_username(packet, rtp_session->ice_user, 32); bytes = switch_stun_packet_length(packet); switch_socket_sendto(rtp_session->sock, rtp_session->remote_addr, 0, (void *)packet, &bytes); rtp_session->stuncount = 25; } else { rtp_session->stuncount--; } return SWITCH_STATUS_SUCCESS; } static void handle_ice(switch_rtp *rtp_session, void *data, switch_size_t len) { switch_stun_packet_t *packet; switch_stun_packet_attribute_t *attr; char username[33] = {0}; unsigned char buf[512] = {0}; memcpy(buf, data, len); packet = switch_stun_packet_parse(buf, sizeof(buf)); rtp_session->last_stun = switch_time_now(); switch_stun_packet_first_attribute(packet, attr); do { switch(attr->type) { case SWITCH_STUN_ATTR_MAPPED_ADDRESS: if (attr->type) { char ip[16]; uint16_t port; switch_stun_packet_attribute_get_mapped_address(attr, ip, &port); } break; case SWITCH_STUN_ATTR_USERNAME: if(attr->type) { switch_stun_packet_attribute_get_username(attr, username, 32); } break; } } while (switch_stun_packet_next_attribute(attr)); if (packet->header.type == SWITCH_STUN_BINDING_REQUEST && !strcmp(rtp_session->user_ice, username)) { uint8_t buf[512]; switch_stun_packet_t *rpacket; char *remote_ip; switch_size_t bytes; memset(buf, 0, sizeof(buf)); rpacket = switch_stun_packet_build_header(SWITCH_STUN_BINDING_RESPONSE, packet->header.id, buf); switch_stun_packet_attribute_add_username(rpacket, username, 32); switch_sockaddr_ip_get(&remote_ip, rtp_session->from_addr); switch_stun_packet_attribute_add_binded_address(rpacket, remote_ip, rtp_session->from_addr->port); bytes = switch_stun_packet_length(rpacket); switch_socket_sendto(rtp_session->sock, rtp_session->from_addr, 0, (void*)rpacket, &bytes); } } SWITCH_DECLARE(void) switch_rtp_init(switch_memory_pool *pool) { if (global_init) { return; } srtp_init(); switch_mutex_init(&port_lock, SWITCH_MUTEX_NESTED, pool); global_init = 1; } SWITCH_DECLARE(switch_port_t) switch_rtp_request_port(void) { switch_port_t port; switch_mutex_lock(port_lock); port = NEXT_PORT; NEXT_PORT += 2; if (port > RTP_END_PORT) { port = RTP_START_PORT; } switch_mutex_unlock(port_lock); return port; } SWITCH_DECLARE(switch_status) switch_rtp_set_local_address(switch_rtp *rtp_session, char *host, switch_port_t port, const char **err) { *err = "Success"; if (switch_sockaddr_info_get(&rtp_session->local_addr, host, SWITCH_UNSPEC, port, 0, rtp_session->pool) != SWITCH_STATUS_SUCCESS) { *err = "Local Address Error!"; return SWITCH_STATUS_FALSE; } if (rtp_session->sock) { switch_socket_close(rtp_session->sock); rtp_session->sock = NULL; } if (switch_socket_create(&rtp_session->sock, AF_INET, SOCK_DGRAM, 0, rtp_session->pool) != SWITCH_STATUS_SUCCESS) { *err = "Socket Error!"; return SWITCH_STATUS_SOCKERR; } if (switch_socket_bind(rtp_session->sock, rtp_session->local_addr) != SWITCH_STATUS_SUCCESS) { *err = "Bind Error!"; return SWITCH_STATUS_FALSE; } if (switch_test_flag(rtp_session, SWITCH_RTP_FLAG_USE_TIMER) || switch_test_flag(rtp_session, SWITCH_RTP_FLAG_NOBLOCK)) { switch_socket_opt_set(rtp_session->sock, APR_SO_NONBLOCK, TRUE); } switch_set_flag(rtp_session, SWITCH_RTP_FLAG_IO); return SWITCH_STATUS_SUCCESS; } SWITCH_DECLARE(switch_status) switch_rtp_set_remote_address(switch_rtp *rtp_session, char *host, switch_port_t port, const char **err) { *err = "Success"; if (switch_sockaddr_info_get(&rtp_session->remote_addr, host, SWITCH_UNSPEC, port, 0, rtp_session->pool) != SWITCH_STATUS_SUCCESS) { *err = "Remote Address Error!"; return SWITCH_STATUS_FALSE; } return SWITCH_STATUS_SUCCESS; } SWITCH_DECLARE(switch_status) switch_rtp_create(switch_rtp **new_rtp_session, uint8_t payload, uint32_t packet_size, uint32_t ms_per_packet, switch_rtp_flag_t flags, char *crypto_key, const char **err, switch_memory_pool *pool) { switch_rtp *rtp_session = NULL; srtp_policy_t policy; char key[MAX_KEY_LEN]; uint32_t ssrc = rand() & 0xffff; *new_rtp_session = NULL; if (packet_size > SWITCH_RTP_MAX_BUF_LEN) { *err = "Packet Size Too Large!"; return SWITCH_STATUS_FALSE; } if (!(rtp_session = switch_core_alloc(pool, sizeof(*rtp_session)))) { *err = "Memory Error!"; return SWITCH_STATUS_MEMERR; } rtp_session->pool = pool; rtp_session->flags = flags; /* for from address on recvfrom calls */ switch_sockaddr_info_get(&rtp_session->from_addr, NULL, SWITCH_UNSPEC, 0, 0, rtp_session->pool); memset(&policy, 0, sizeof(policy)); if (crypto_key) { int len; switch_set_flag(rtp_session, SWITCH_RTP_FLAG_SECURE); crypto_policy_set_rtp_default(&policy.rtp); crypto_policy_set_rtcp_default(&policy.rtcp); policy.ssrc.type = ssrc_any_inbound; policy.ssrc.value = ssrc; policy.key = (uint8_t *) key; policy.next = NULL; policy.rtp.sec_serv = sec_serv_conf_and_auth; policy.rtcp.sec_serv = sec_serv_none; /* * read key from hexadecimal on command line into an octet string */ len = hex_string_to_octet_string(key, crypto_key, MASTER_KEY_LEN*2); /* check that hex string is the right length */ if (len < MASTER_KEY_LEN*2) { switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "error: too few digits in key/salt " "(should be %d hexadecimal digits, found %d)\n", MASTER_KEY_LEN*2, len); *err = "Crypt Error"; return SWITCH_STATUS_FALSE; } if (strlen(crypto_key) > MASTER_KEY_LEN*2) { switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "error: too many digits in key/salt " "(should be %d hexadecimal digits, found %u)\n", MASTER_KEY_LEN*2, (unsigned)strlen(crypto_key)); *err = "Crypt Error"; return SWITCH_STATUS_FALSE; } //switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "set master key/salt to %s/", octet_string_hex_string(key, 16)); //switch_log_printf(SWITCH_CHANNEL_LOG_CLEAN, SWITCH_LOG_DEBUG, "%s\n", octet_string_hex_string(key+16, 14)); switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "Activating Secure RTP!\n"); } rtp_session->send_msg.header.ssrc = htonl(ssrc); rtp_session->send_msg.header.ts = 0; rtp_session->send_msg.header.seq = (uint16_t) rand(); rtp_session->send_msg.header.m = 0; rtp_session->send_msg.header.pt = (uint8_t)htonl(payload); rtp_session->send_msg.header.version = 2; rtp_session->send_msg.header.p = 0; rtp_session->send_msg.header.x = 0; rtp_session->send_msg.header.cc = 0; rtp_session->recv_msg.header.ssrc = htonl(ssrc); rtp_session->recv_msg.header.ts = 0; rtp_session->recv_msg.header.seq = 0; rtp_session->recv_msg.header.m = 0; rtp_session->recv_msg.header.pt = (uint8_t)htonl(payload); rtp_session->recv_msg.header.version = 2; rtp_session->recv_msg.header.p = 0; rtp_session->recv_msg.header.x = 0; rtp_session->recv_msg.header.cc = 0; rtp_session->seq = rtp_session->send_msg.header.seq; rtp_session->payload = payload; rtp_session->ms_per_packet = ms_per_packet; rtp_session->packet_size = packet_size; rtp_session->next_read = switch_time_now() + rtp_session->ms_per_packet; if (switch_test_flag(rtp_session, SWITCH_RTP_FLAG_SECURE)) { err_status_t stat; if ((stat = srtp_create(&rtp_session->recv_ctx, &policy))) { switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "Error allocating srtp [%d]\n", stat); *err = "Crypt Error"; return SWITCH_STATUS_FALSE; } if ((stat = srtp_create(&rtp_session->send_ctx, &policy))) { switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "Error allocating srtp [%d]\n", stat); *err = "Crypt Error"; return SWITCH_STATUS_FALSE; } } *new_rtp_session = rtp_session; return SWITCH_STATUS_SUCCESS; } SWITCH_DECLARE(switch_rtp *)switch_rtp_new(char *rx_host, switch_port_t rx_port, char *tx_host, switch_port_t tx_port, uint8_t payload, uint32_t packet_size, uint32_t ms_per_packet, switch_rtp_flag_t flags, char *crypto_key, const char **err, switch_memory_pool *pool) { switch_rtp *rtp_session; if (switch_rtp_create(&rtp_session, payload, packet_size, ms_per_packet, flags, crypto_key, err, pool) != SWITCH_STATUS_SUCCESS) { return NULL; } if (switch_rtp_set_remote_address(rtp_session, tx_host, tx_port, err) != SWITCH_STATUS_SUCCESS) { return NULL; } if (switch_rtp_set_local_address(rtp_session, rx_host, rx_port, err) != SWITCH_STATUS_SUCCESS) { return NULL; } return rtp_session; } SWITCH_DECLARE(switch_status) switch_rtp_activate_ice(switch_rtp *rtp_session, char *login, char *rlogin) { char ice_user[80]; char user_ice[80]; snprintf(ice_user, sizeof(ice_user), "%s%s", login, rlogin); snprintf(user_ice, sizeof(user_ice), "%s%s", rlogin, login); rtp_session->ice_user = switch_core_strdup(rtp_session->pool, ice_user); rtp_session->user_ice = switch_core_strdup(rtp_session->pool, user_ice); if (rtp_session->ice_user) { if (ice_out(rtp_session) != SWITCH_STATUS_SUCCESS) { return -1; } } return SWITCH_STATUS_SUCCESS; } SWITCH_DECLARE(void) switch_rtp_kill_socket(switch_rtp *rtp_session) { apr_socket_shutdown(rtp_session->sock, APR_SHUTDOWN_READWRITE); switch_clear_flag(rtp_session, SWITCH_RTP_FLAG_IO); } SWITCH_DECLARE(void) switch_rtp_destroy(switch_rtp **rtp_session) { switch_rtp_kill_socket(*rtp_session); switch_socket_close((*rtp_session)->sock); if (switch_test_flag((*rtp_session), SWITCH_RTP_FLAG_SECURE)) { srtp_dealloc((*rtp_session)->recv_ctx); srtp_dealloc((*rtp_session)->send_ctx); } *rtp_session = NULL; return; } SWITCH_DECLARE(switch_socket_t *)switch_rtp_get_rtp_socket(switch_rtp *rtp_session) { return rtp_session->sock; } SWITCH_DECLARE(void) switch_rtp_set_default_packet_size(switch_rtp *rtp_session, uint16_t packet_size) { rtp_session->packet_size = packet_size; } SWITCH_DECLARE(uint32_t) switch_rtp_get_default_packet_size(switch_rtp *rtp_session) { return rtp_session->packet_size; } SWITCH_DECLARE(void) switch_rtp_set_default_payload(switch_rtp *rtp_session, uint8_t payload) { rtp_session->payload = payload; } SWITCH_DECLARE(uint32_t) switch_rtp_get_default_payload(switch_rtp *rtp_session) { return rtp_session->payload; } SWITCH_DECLARE(void) switch_rtp_set_invald_handler(switch_rtp *rtp_session, switch_rtp_invalid_handler on_invalid) { rtp_session->invalid_handler = on_invalid; } static int rtp_common_read(switch_rtp *rtp_session, void *data, int *payload_type, switch_frame_flag *flags) { switch_size_t bytes; switch_status status; for(;;) { bytes = sizeof(rtp_msg_t); status = switch_socket_recvfrom(rtp_session->from_addr, rtp_session->sock, 0, (void *)&rtp_session->recv_msg, &bytes); if (!switch_test_flag(rtp_session, SWITCH_RTP_FLAG_IO)) { return -1; } if (bytes < 0) { return (int)bytes; } else if (bytes > 0 && switch_test_flag(rtp_session, SWITCH_RTP_FLAG_SECURE)) { int sbytes = (int)bytes; err_status_t stat; stat = srtp_unprotect(rtp_session->recv_ctx, &rtp_session->recv_msg.header, &sbytes); if (stat) { switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "error: srtp unprotection failed with code %d%s\n", stat, stat == err_status_replay_fail ? " (replay check failed)" : stat == err_status_auth_fail ? " (auth check failed)" : ""); return -1; } bytes = sbytes; } if (switch_test_flag(rtp_session, SWITCH_RTP_FLAG_USE_TIMER)) { if ((switch_time_now() - rtp_session->next_read) > 1000) { /* We're late! We're Late!*/ memset(&rtp_session->recv_msg, 0, SWITCH_RTP_CNG_PAYLOAD); rtp_session->recv_msg.header.pt = SWITCH_RTP_CNG_PAYLOAD; *flags |= SFF_CNG; /* Set the next waypoint and return a CNG frame */ rtp_session->next_read += rtp_session->ms_per_packet; *payload_type = SWITCH_RTP_CNG_PAYLOAD; return SWITCH_RTP_CNG_PAYLOAD; } if (!switch_test_flag(rtp_session, SWITCH_RTP_FLAG_NOBLOCK) && status == SWITCH_STATUS_BREAK) { switch_yield(1000); continue; } } if (status == SWITCH_STATUS_BREAK || bytes == 0) { return 0; } if (rtp_session->recv_msg.header.version != 2) { if (rtp_session->recv_msg.header.version == 0 && rtp_session->ice_user) { handle_ice(rtp_session, (void *) &rtp_session->recv_msg, bytes); } if (rtp_session->invalid_handler) { rtp_session->invalid_handler(rtp_session, rtp_session->sock, (void *) &rtp_session->recv_msg, bytes, rtp_session->from_addr); } return 0; } break; } rtp_session->last_read = switch_time_now(); rtp_session->next_read += rtp_session->ms_per_packet; *payload_type = rtp_session->recv_msg.header.pt; if (*payload_type == SWITCH_RTP_CNG_PAYLOAD) { *flags |= SFF_CNG; } return (int)(bytes - rtp_header_len); } SWITCH_DECLARE(switch_status) switch_rtp_read(switch_rtp *rtp_session, void *data, uint32_t *datalen, int *payload_type, switch_frame_flag *flags) { int bytes = rtp_common_read(rtp_session, data, payload_type, flags); if (bytes < 0) { *datalen = 0; return SWITCH_STATUS_GENERR; } *datalen = bytes; memcpy(data, rtp_session->recv_msg.body, bytes); return SWITCH_STATUS_SUCCESS; } SWITCH_DECLARE(switch_status) switch_rtp_zerocopy_read(switch_rtp *rtp_session, void **data, uint32_t *datalen, int *payload_type, switch_frame_flag *flags) { int bytes = rtp_common_read(rtp_session, data, payload_type, flags); *data = rtp_session->recv_msg.body; if (bytes < 0) { *datalen = 0; return SWITCH_STATUS_GENERR; } *datalen = bytes; return SWITCH_STATUS_SUCCESS; } static int rtp_common_write(switch_rtp *rtp_session, void *data, uint32_t datalen, uint8_t payload) { switch_size_t bytes; if (rtp_session->packet_size > datalen && (payload == rtp_session->payload)) { if (!rtp_session->packet_buffer) { if (switch_buffer_create(rtp_session->pool, &rtp_session->packet_buffer, rtp_session->packet_size * 2) != SWITCH_STATUS_SUCCESS) { switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "Buffer memory error\n"); return -1; } } switch_buffer_write(rtp_session->packet_buffer, data, datalen); if (switch_buffer_inuse(rtp_session->packet_buffer) >= rtp_session->packet_size) { switch_buffer_read(rtp_session->packet_buffer, rtp_session->send_msg.body, rtp_session->packet_size); datalen = rtp_session->packet_size; } else { return datalen; } } else { memcpy(rtp_session->send_msg.body, data, datalen); } bytes = datalen + rtp_header_len; if (switch_test_flag(rtp_session, SWITCH_RTP_FLAG_SECURE)) { int sbytes = (int)bytes; err_status_t stat; stat = srtp_protect(rtp_session->send_ctx, &rtp_session->send_msg.header, &sbytes); if (stat) { switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "error: srtp unprotection failed with code %d\n", stat); } bytes = sbytes; } switch_socket_sendto(rtp_session->sock, rtp_session->remote_addr, 0, (void*)&rtp_session->send_msg, &bytes); if (rtp_session->ice_user) { if (ice_out(rtp_session) != SWITCH_STATUS_SUCCESS) { return -1; } } return (int)bytes; } SWITCH_DECLARE(int) switch_rtp_write(switch_rtp *rtp_session, void *data, uint32_t datalen, uint32_t ts) { if (!switch_test_flag(rtp_session, SWITCH_RTP_FLAG_IO) || !rtp_session->remote_addr) { return -1; } rtp_session->ts += ts; rtp_session->seq = ntohs(rtp_session->seq) + 1; rtp_session->seq = htons(rtp_session->seq); rtp_session->send_msg.header.seq = rtp_session->seq; rtp_session->send_msg.header.ts = htonl(rtp_session->ts); rtp_session->payload = (uint8_t)htonl(rtp_session->payload); return rtp_common_write(rtp_session, data, datalen, rtp_session->payload); } SWITCH_DECLARE(int) switch_rtp_write_payload(switch_rtp *rtp_session, void *data, uint16_t datalen, uint8_t payload, uint32_t ts, uint16_t mseq) { if (!switch_test_flag(rtp_session, SWITCH_RTP_FLAG_IO) || !rtp_session->remote_addr) { return -1; } rtp_session->ts += ts; rtp_session->send_msg.header.seq = htons(mseq); rtp_session->send_msg.header.ts = htonl(rtp_session->ts); rtp_session->send_msg.header.pt = (uint8_t)htonl(payload); return rtp_common_write(rtp_session, data, datalen, payload); } SWITCH_DECLARE(uint32_t) switch_rtp_get_ssrc(switch_rtp *rtp_session) { return rtp_session->send_msg.header.ssrc; } SWITCH_DECLARE(void) switch_rtp_set_private(switch_rtp *rtp_session, void *private_data) { rtp_session->private_data = private_data; } SWITCH_DECLARE(void *)switch_rtp_get_private(switch_rtp *rtp_session) { return rtp_session->private_data; }