/* A Media Gateway Control Protocol Media Gateway: RFC 3435 */ /* The protocol implementation */ /* * (C) 2009-2012 by Holger Hans Peter Freyther * (C) 2009-2012 by On-Waves * All Rights Reserved * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU Affero General Public License as published by * the Free Software Foundation; either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Affero General Public License for more details. * * You should have received a copy of the GNU Affero General Public License * along with this program. If not, see . * */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* Contains the last successfully resolved endpoint name. This variable is used * for the unit-tests to verify that the endpoint was correctly resolved. */ static char debug_last_endpoint_name[MGCP_ENDPOINT_MAXLEN]; /* Called from unit-tests only */ char *mgcp_debug_get_last_endpoint_name(void) { return debug_last_endpoint_name; } /* A combination of LOGPENDP and LOGPTRUNK that automatically falls back to * LOGPTRUNK when the endp parameter is NULL */ #define LOGPEPTR(endp, trunk, cat, level, fmt, args...) \ do { \ if (endp) \ LOGPENDP(endp, cat, level, fmt, ## args); \ else \ LOGPTRUNK(trunk, cat, level, fmt, ## args); \ } while (0) /* Request data passed to the request handler */ struct mgcp_request_data { /* request name (e.g. "MDCX") */ char name[4+1]; /* parsing results from the MGCP header (trans id, endpoint name ...) */ struct mgcp_parse_data *pdata; /* pointer to endpoint resource (may be NULL for wildcarded requests) */ struct mgcp_endpoint *endp; /* pointer to trunk resource */ struct mgcp_trunk *trunk; /* set to true when the request has been classified as wildcarded */ bool wildcarded; /* Set to true when the request is targeted at the "null" endpoint */ bool null_endp; /* contains cause code in case of problems during endp/trunk resolution */ int mgcp_cause; }; /* Request handler specification, here we specify an array with function * pointers to the various MGCP requests implemented below */ struct mgcp_request { /* request name (e.g. "MDCX") */ char *name; /* function pointer to the request handler */ struct msgb *(*handle_request)(struct mgcp_request_data *data); /* a human readable name that describes the request */ char *debug_name; }; static struct msgb *handle_audit_endpoint(struct mgcp_request_data *data); static struct msgb *handle_create_con(struct mgcp_request_data *data); static struct msgb *handle_delete_con(struct mgcp_request_data *data); static struct msgb *handle_modify_con(struct mgcp_request_data *data); static struct msgb *handle_rsip(struct mgcp_request_data *data); static struct msgb *handle_noti_req(struct mgcp_request_data *data); static const struct mgcp_request mgcp_requests[] = { { .name = "AUEP", .handle_request = handle_audit_endpoint, .debug_name = "AuditEndpoint" }, { .name = "CRCX", .handle_request = handle_create_con, .debug_name = "CreateConnection", }, { .name = "DLCX", .handle_request = handle_delete_con, .debug_name = "DeleteConnection", }, { .name = "MDCX", .handle_request = handle_modify_con, .debug_name = "ModifiyConnection", }, { .name = "RQNT", .handle_request = handle_noti_req, .debug_name = "NotificationRequest", }, /* SPEC extension */ { .name = "RSIP", .handle_request = handle_rsip, .debug_name = "ReSetInProgress", }, }; /* Initalize transcoder */ static int setup_rtp_processing(struct mgcp_endpoint *endp, struct mgcp_conn_rtp *conn) { struct mgcp_config *cfg = endp->trunk->cfg; struct mgcp_conn_rtp *conn_src = NULL; struct mgcp_conn_rtp *conn_dst = conn; struct mgcp_conn *_conn; switch (conn->type) { case MGCP_RTP_DEFAULT: case MGCP_RTP_OSMUX: case MGCP_RTP_IUUP: break; default: LOGPENDP(endp, DLMGCP, LOGL_NOTICE, "RTP-setup: Endpoint is not configured as RTP default, stopping here!\n"); return 0; } if (conn->conn->mode == MGCP_CONN_LOOPBACK) { LOGPENDP(endp, DLMGCP, LOGL_NOTICE, "RTP-setup: Endpoint is in loopback mode, stopping here!\n"); return 0; } /* Find the "sister" connection */ llist_for_each_entry(_conn, &endp->conns, entry) { if (_conn->id != conn->conn->id) { conn_src = &_conn->u.rtp; break; } } return cfg->setup_rtp_processing_cb(endp, conn_dst, conn_src); } /* Helper function to allocate some memory for responses and retransmissions */ static struct msgb *mgcp_msgb_alloc(void *ctx) { struct msgb *msg; msg = msgb_alloc_headroom_c(ctx, 4096, 128, "MGCP msg"); if (!msg) { LOGP(DLMGCP, LOGL_ERROR, "Failed to msgb for MGCP data.\n"); return NULL; } return msg; } /* Helper function for do_retransmission() and create_resp() */ static struct msgb *create_retransmission_response(const struct mgcp_endpoint *endp) { struct msgb *msg = mgcp_msgb_alloc(endp->trunk); if (!msg) return NULL; msg->l2h = msgb_put(msg, strlen(endp->last_response)); memcpy(msg->l2h, endp->last_response, msgb_l2len(msg)); mgcp_disp_msg(msg->l2h, msgb_l2len(msg), "Retransmitted response"); return msg; } static struct msgb *create_resp(void *msgctx, struct mgcp_endpoint *endp, int code, const char *txt, const char *msg, const char *trans, const char *param, const char *sdp) { int len; struct msgb *res; OSMO_ASSERT(msgctx != 0); res = mgcp_msgb_alloc(msgctx); if (!res) return NULL; len = snprintf((char *)res->data, 2048, "%d %s%s%s\r\n%s", code, trans, txt, param ? param : "", sdp ? sdp : ""); if (len < 0) { LOGPENDP(endp, DLMGCP, LOGL_ERROR, "Failed to sprintf MGCP response.\n"); msgb_free(res); return NULL; } res->l2h = msgb_put(res, len); LOGPENDP(endp, DLMGCP, LOGL_DEBUG, "Generated response: code=%d\n", code); mgcp_disp_msg(res->l2h, msgb_l2len(res), "Generated response"); /* * Remember the last transmission per endpoint. */ if (endp) { struct mgcp_trunk *trunk = endp->trunk; talloc_free(endp->last_response); talloc_free(endp->last_trans); endp->last_trans = talloc_strdup(trunk->endpoints, trans); endp->last_response = talloc_strndup(trunk->endpoints, (const char *)res->l2h, msgb_l2len(res)); } return res; } static struct msgb *create_ok_resp_with_param(void *msgctx, struct mgcp_endpoint *endp, int code, const char *msg, const char *trans, const char *param) { return create_resp(msgctx, endp, code, " OK", msg, trans, param, NULL); } static struct msgb *create_ok_response(void *msgctx, struct mgcp_endpoint *endp, int code, const char *msg, const char *trans) { return create_ok_resp_with_param(msgctx, endp, code, msg, trans, NULL); } static struct msgb *create_err_response(void *msgctx, struct mgcp_endpoint *endp, int code, const char *msg, const char *trans) { return create_resp(msgctx, endp, code, " FAIL", msg, trans, NULL, NULL); } /* Format MGCP response string (with SDP attached) */ static struct msgb *create_response_with_sdp(struct mgcp_endpoint *endp, struct mgcp_conn_rtp *conn, const char *msg, const char *trans_id, bool add_epname, bool add_conn_id) { /* cfg->local_ip allows overwritting the announced IP address with * regards to the one we actually bind to. Useful in behind-NAT * scenarios. * TODO: we may want to define another local_ip_osmux var to * us for OSMUX connections. Perhaps adding a new internal API to get it * based on conn type. */ const char *addr = strlen(endp->trunk->cfg->local_ip) ? endp->trunk->cfg->local_ip : conn->end.local_addr; struct msgb *sdp; int rc; struct msgb *result; sdp = msgb_alloc_headroom_c(endp->trunk, 4096, 128, "sdp record"); if (!sdp) return NULL; /* Attach optional endpoint name */ if (add_epname) { rc = msgb_printf(sdp, "Z: %s\r\n", endp->name); if (rc < 0) goto error; } /* Attach optional connection id */ if (add_conn_id) { rc = msgb_printf(sdp, "I: %s\r\n", conn->conn->id); if (rc < 0) goto error; } /* Attach optional OSMUX parameters */ if (mgcp_conn_rtp_is_osmux(conn)) { rc = msgb_printf(sdp, MGCP_X_OSMO_OSMUX_HEADER " %u\r\n", conn->osmux.local_cid); if (rc < 0) goto error; } /* Attach line break to separate the parameters from the SDP block */ rc = msgb_printf(sdp, "\r\n"); rc = mgcp_write_response_sdp(endp, conn, sdp, addr); if (rc < 0) goto error; result = create_resp(endp->trunk, endp, 200, " OK", msg, trans_id, NULL, (char *)sdp->data); msgb_free(sdp); return result; error: msgb_free(sdp); return NULL; } /* Send out dummy packet to keep the connection open, if the connection is an * osmux connection, send the dummy packet via OSMUX */ static void send_dummy(struct mgcp_endpoint *endp, struct mgcp_conn_rtp *conn) { /* Avoid sending dummy packet if the remote address was not yet * configured through CRCX/MDCX: */ if (!mgcp_rtp_end_remote_addr_available(&conn->end)) return; if (mgcp_conn_rtp_is_osmux(conn)) osmux_send_dummy(conn); else mgcp_send_dummy(endp, conn); } /* handle incoming messages: * - this can be a command (four letters, space, transaction id) * - or a response (three numbers, space, transaction id) */ struct msgb *mgcp_handle_message(struct mgcp_config *cfg, struct msgb *msg) { struct rate_ctr_group *rate_ctrs = cfg->ratectr.mgcp_general_ctr_group; struct mgcp_parse_data pdata; struct mgcp_request_data rq; int rc, i, code, handled = 0; struct msgb *resp = NULL; char *data; debug_last_endpoint_name[0] = '\0'; /* Count all messages, even incorect ones */ rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_GENERAL_RX_MSGS_TOTAL)); if (msgb_l2len(msg) < 4) { LOGP(DLMGCP, LOGL_ERROR, "msg too short: %d\n", msg->len); rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_GENERAL_RX_FAIL_MSG_PARSE)); return NULL; } if (mgcp_msg_terminate_nul(msg)) { rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_GENERAL_RX_FAIL_MSG_PARSE)); return NULL; } mgcp_disp_msg(msg->l2h, msgb_l2len(msg), "Received message"); /* attempt to treat it as a response */ if (sscanf((const char *)&msg->l2h[0], "%3d %*s", &code) == 1) { LOGP(DLMGCP, LOGL_DEBUG, "Response: Code: %d\n", code); rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_GENERAL_RX_FAIL_MSG_PARSE)); return NULL; } /* Parse message, extract endpoint name and transaction identifier and request name etc. */ memset(&pdata, 0, sizeof(pdata)); memset(&rq, 0, sizeof(rq)); pdata.cfg = cfg; memcpy(rq.name, (const char *)&msg->l2h[0], sizeof(rq.name)-1); msg->l3h = &msg->l2h[4]; data = mgcp_strline((char *)msg->l3h, &pdata.save); rc = mgcp_parse_header(&pdata, data); if (rc < 0) { LOGP(DLMGCP, LOGL_ERROR, "%s: failed to parse MCGP message\n", rq.name); rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_GENERAL_RX_FAIL_MSG_PARSE)); return create_err_response(cfg, NULL, -rc, rq.name, "000000"); } /* Locate endpoint and trunk, if no endpoint can be located try at least to identify the trunk. */ rq.pdata = &pdata; rq.wildcarded = mgcp_endp_is_wildcarded(pdata.epname); if (!rq.wildcarded) rq.null_endp = mgcp_endp_is_null(pdata.epname); if (!rq.null_endp) rq.endp = mgcp_endp_by_name(&rc, pdata.epname, pdata.cfg); rq.mgcp_cause = rc; if (!rq.endp) { rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_GENERAL_RX_FAIL_NO_ENDPOINT)); if (rq.wildcarded) { /* If we are unable to find the endpoint we still may be able to identify the trunk. Some * request handlers will still be able to perform a useful action if the request refers to * the whole trunk (wildcarded request). */ LOGP(DLMGCP, LOGL_NOTICE, "%s: cannot find endpoint \"%s\", cause=%d -- trying to identify trunk...\n", rq.name, pdata.epname, -rq.mgcp_cause); rq.trunk = mgcp_trunk_by_name(pdata.cfg, pdata.epname); if (!rq.trunk) { LOGP(DLMGCP, LOGL_ERROR, "%s: failed to identify trunk for endpoint \"%s\" -- abort\n", rq.name, pdata.epname); return create_err_response(cfg, NULL, -rq.mgcp_cause, rq.name, pdata.trans); } } else if (!rq.null_endp) { /* If the endpoint name suggests that the request refers to a specific endpoint, then the * request cannot be handled and we must stop early. */ LOGP(DLMGCP, LOGL_NOTICE, "%s: cannot find endpoint \"%s\", cause=%d -- abort\n", rq.name, pdata.epname, -rq.mgcp_cause); return create_err_response(cfg, NULL, -rq.mgcp_cause, rq.name, pdata.trans); } /* else: Handle special "null" endpoint below (with rq.endp=NULL, rq.trunk=NULL) */ } else { osmo_strlcpy(debug_last_endpoint_name, rq.endp->name, sizeof(debug_last_endpoint_name)); rq.trunk = rq.endp->trunk; rq.mgcp_cause = 0; /* Check if we have to retransmit a response from a previous transaction */ if (pdata.trans && rq.endp->last_trans && strcmp(rq.endp->last_trans, pdata.trans) == 0) { rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_GENERAL_RX_MSGS_RETRANSMITTED)); return create_retransmission_response(rq.endp); } } /* Find an appropriate handler for the current request and execute it */ for (i = 0; i < ARRAY_SIZE(mgcp_requests); i++) { if (strcmp(mgcp_requests[i].name, rq.name) == 0) { /* Execute request handler */ if (rq.endp) LOGP(DLMGCP, LOGL_INFO, "%s: executing request handler \"%s\" for endpoint resource \"%s\"\n", rq.name, mgcp_requests[i].debug_name, rq.endp->name); else LOGP(DLMGCP, LOGL_INFO, "%s: executing request handler \"%s\" for trunk resource of endpoint \"%s\"\n", rq.name, mgcp_requests[i].debug_name, pdata.epname); resp = mgcp_requests[i].handle_request(&rq); handled = 1; break; } } /* Check if the MGCP request was handled and increment rate counters accordingly. */ if (handled) { rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_GENERAL_RX_MSGS_HANDLED)); } else { rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_GENERAL_RX_MSGS_UNHANDLED)); LOGP(DLMGCP, LOGL_ERROR, "MSG with type: '%.4s' not handled\n", &msg->l2h[0]); } return resp; } /* AUEP command handler, processes the received command */ static struct msgb *handle_audit_endpoint(struct mgcp_request_data *rq) { LOGPENDP(rq->endp, DLMGCP, LOGL_NOTICE, "AUEP: auditing endpoint ...\n"); /* Auditing "null" endpoint is allowed for keepalive purposes. There's no rq->endp nor rq->trunk in this case. */ if (rq->null_endp) return create_ok_response(rq->pdata->cfg, NULL, 200, "AUEP", rq->pdata->trans); if (!rq->endp || !mgcp_endp_avail(rq->endp)) { LOGPENDP(rq->endp, DLMGCP, LOGL_ERROR, "AUEP: selected endpoint not available!\n"); return create_err_response(rq->trunk, NULL, 501, "AUEP", rq->pdata->trans); } return create_ok_response(rq->trunk, rq->endp, 200, "AUEP", rq->pdata->trans); } /* Try to find a free port by attempting to bind on it. Also handle the * counter that points on the next free port. Since we have a pointer * to the next free port, binding should in work on the first attempt in * general. In case of failure the next port is tried until the whole port * range is tried once. */ static int allocate_port(struct mgcp_endpoint *endp, struct mgcp_conn_rtp *conn) { int i; struct mgcp_port_range *range; unsigned int tries; OSMO_ASSERT(conn); range = &endp->trunk->cfg->net_ports; pthread_mutex_lock(&range->lock); /* attempt to find a port */ tries = (range->range_end - range->range_start) / 2; for (i = 0; i < tries; ++i) { int rc; if (range->last_port >= range->range_end) range->last_port = range->range_start; rc = mgcp_bind_net_rtp_port(endp, range->last_port, conn); range->last_port += 2; if (rc == 0) { pthread_mutex_unlock(&range->lock); return 0; } } pthread_mutex_unlock(&range->lock); LOGPENDP(endp, DLMGCP, LOGL_ERROR, "Allocating a RTP/RTCP port failed %u times.\n", tries); return -1; } /*! Helper function for check_local_cx_options() to get a pointer of the next * lco option identifier * \param[in] lco string * \returns pointer to the beginning of the LCO identifier, NULL on failure */ char *get_lco_identifier(const char *options) { char *ptr; unsigned int count = 0; /* Jump to the end of the lco identifier */ ptr = strstr(options, ":"); if (!ptr) return NULL; /* Walk backwards until the pointer points to the beginning of the * lco identifier. We know that we stand at the beginning when we * are either at the beginning of the memory or see a space or * comma. (this is tolerant, it will accept a:10, b:11 as well as * a:10,b:11) */ while (1) { /* Endless loop protection */ if (count > 10000) return NULL; else if (ptr < options || *ptr == ' ' || *ptr == ',') { ptr++; break; } ptr--; count++; } /* Check if we got any result */ if (*ptr == ':') return NULL; return ptr; } /*! Check the LCO option. This function checks for multiple appearence of LCO * options, which is illegal * \param[in] ctx talloc context * \param[in] lco string * \returns 0 on success, -1 on failure */ int check_local_cx_options(void *ctx, const char *options) { int i; char *options_copy; char *lco_identifier; char *lco_identifier_end; char *next_lco_identifier; char **lco_seen; unsigned int lco_seen_n = 0; if (!options) return -1; lco_seen = (char **)talloc_zero_size(ctx, strlen(options) * sizeof(char *)); options_copy = talloc_strdup(ctx, options); lco_identifier = options_copy; do { /* Move the lco_identifier pointer to the beginning of the * current lco option identifier */ lco_identifier = get_lco_identifier(lco_identifier); if (!lco_identifier) goto error; /* Look ahead to the next LCO option early, since we * will parse destructively */ next_lco_identifier = strstr(lco_identifier + 1, ","); /* Pinch off the end of the lco field identifier name * and see if we still got something, also check if * there is some value after the colon. */ lco_identifier_end = strstr(lco_identifier, ":"); if (!lco_identifier_end) goto error; if (*(lco_identifier_end + 1) == ' ' || *(lco_identifier_end + 1) == ',' || *(lco_identifier_end + 1) == '\0') goto error; *lco_identifier_end = '\0'; if (strlen(lco_identifier) == 0) goto error; /* Check if we have already seen the current field identifier * before. If yes, we must bail, an LCO must only appear once * in the LCO string */ for (i = 0; i < lco_seen_n; i++) { if (strcasecmp(lco_seen[i], lco_identifier) == 0) goto error; } lco_seen[lco_seen_n] = lco_identifier; lco_seen_n++; /* The first identifier must always be found at the beginnning * of the LCO string */ if (lco_seen[0] != options_copy) goto error; /* Go to the next lco option */ lco_identifier = next_lco_identifier; } while (lco_identifier); talloc_free(lco_seen); talloc_free(options_copy); return 0; error: talloc_free(lco_seen); talloc_free(options_copy); return -1; } /* Set the LCO from a string (see RFC 3435). * The string is stored in the 'string' field. A NULL string is handled exactly * like an empty string, the 'string' field is never NULL after this function * has been called. */ static int set_local_cx_options(void *ctx, struct mgcp_lco *lco, const char *options) { char *lco_id; char codec[17]; char nt[17]; int len; if (!options) return 0; if (strlen(options) == 0) return 0; /* Make sure the encoding of the LCO is consistant before we proceed */ if (check_local_cx_options(ctx, options) != 0) { LOGP(DLMGCP, LOGL_ERROR, "local CX options: Internal inconsistency in Local Connection Options!\n"); return 524; } talloc_free(lco->string); lco->string = talloc_strdup(ctx, options); lco_id = lco->string; while ((lco_id = get_lco_identifier(lco_id))) { switch (tolower(lco_id[0])) { case 'p': if (sscanf(lco_id + 1, ":%d-%d", &lco->pkt_period_min, &lco->pkt_period_max) == 1) lco->pkt_period_max = lco->pkt_period_min; break; case 'a': /* FIXME: LCO also supports the negotiation of more than one codec. * (e.g. a:PCMU;G726-32) But this implementation only supports a single * codec only. Ignoring all but the first codec. */ if (sscanf(lco_id + 1, ":%16[^,;]", codec) == 1) { talloc_free(lco->codec); /* MGCP header is case insensive, and we'll need codec in uppercase when using it later: */ len = strlen(codec); lco->codec = talloc_size(ctx, len + 1); osmo_str_toupper_buf(lco->codec, len + 1, codec); } break; case 'n': if (lco_id[1] == 't' && sscanf(lco_id + 2, ":%16[^,]", nt) == 1) break; /* else: fall throught to print notice log */ default: LOGP(DLMGCP, LOGL_NOTICE, "LCO: unhandled option: '%c'/%d in \"%s\"\n", *lco_id, *lco_id, lco->string); break; } lco_id = strchr(lco_id, ','); if (!lco_id) break; } LOGP(DLMGCP, LOGL_DEBUG, "local CX options: lco->pkt_period_max: %i, lco->codec: %s\n", lco->pkt_period_max, lco->codec); /* Check if the packetization fits the 20ms raster */ if (lco->pkt_period_min % 20 && lco->pkt_period_max % 20) { LOGP(DLMGCP, LOGL_ERROR, "local CX options: packetization interval is not a multiple of 20ms!\n"); return 535; } return 0; } void mgcp_rtp_end_config(struct mgcp_endpoint *endp, int expect_ssrc_change, struct mgcp_rtp_end *rtp) { struct mgcp_trunk *trunk = endp->trunk; int patch_ssrc = expect_ssrc_change && trunk->force_constant_ssrc; rtp->force_aligned_timing = trunk->force_aligned_timing; rtp->force_constant_ssrc = patch_ssrc ? 1 : 0; rtp->rfc5993_hr_convert = trunk->rfc5993_hr_convert; LOGPENDP(endp, DLMGCP, LOGL_DEBUG, "Configuring RTP endpoint: local port %d%s%s\n", osmo_sockaddr_port(&rtp->addr.u.sa), rtp->force_aligned_timing ? ", force constant timing" : "", rtp->force_constant_ssrc ? ", force constant ssrc" : ""); } uint32_t mgcp_rtp_packet_duration(const struct mgcp_endpoint *endp, const struct mgcp_rtp_end *rtp) { int f = 0; /* Get the number of frames per channel and packet */ if (rtp->frames_per_packet) f = rtp->frames_per_packet; else if (rtp->packet_duration_ms && rtp->codec->frame_duration_num) { int den = 1000 * rtp->codec->frame_duration_num; f = (rtp->packet_duration_ms * rtp->codec->frame_duration_den + den / 2) / den; } return rtp->codec->rate * f * rtp->codec->frame_duration_num / rtp->codec->frame_duration_den; } /*! Initializes osmux socket if not yet initialized. Parses Osmux CID from MGCP line. * \param[in] endp Endpoint willing to initialize osmux * \param[in] line Line X-Osmux from MGCP header msg to parse * \returns OSMUX CID, -1 for wildcard, -2 on parse error, -3 on osmux initalize error */ static int mgcp_osmux_setup(struct mgcp_endpoint *endp, const char *line) { if (!endp->trunk->cfg->osmux.initialized) { if (osmux_init(endp->trunk) < 0) { LOGPENDP(endp, DOSMUX, LOGL_ERROR, "Cannot init OSMUX\n"); return -3; } LOGPENDP(endp, DOSMUX, LOGL_NOTICE, "OSMUX socket has been set up\n"); } return mgcp_parse_osmux_cid(line); } /* Process codec information contained in CRCX/MDCX */ static int handle_codec_info(struct mgcp_conn_rtp *conn, struct mgcp_request_data *rq, int have_sdp, bool crcx) { struct mgcp_endpoint *endp = rq->endp; struct mgcp_conn *conn_dst; struct mgcp_conn_rtp *conn_dst_rtp; int rc; char *cmd; if (crcx) cmd = "CRCX"; else cmd = "MDCX"; /* Collect codec information */ if (have_sdp) { /* If we have SDP, we ignore the local connection options and * use only the SDP information. */ mgcp_codec_reset_all(conn); rc = mgcp_parse_sdp_data(endp, conn, rq->pdata); if (rc != 0) { LOGPCONN(conn->conn, DLMGCP, LOGL_ERROR, "%s: sdp not parseable\n", cmd); /* See also RFC 3661: Protocol error */ return 510; } } else if (endp->local_options.codec) { /* When no SDP is available, we use the codec information from * the local connection options (if present) */ mgcp_codec_reset_all(conn); rc = mgcp_codec_add(conn, PTYPE_UNDEFINED, endp->local_options.codec, NULL); if (rc != 0) goto error; } /* Make sure we always set a sane default codec */ if (conn->end.codecs_assigned == 0) { /* When SDP and/or LCO did not supply any codec information, * than it makes sense to pick a sane default: (payload-type 0, * PCMU), see also: OS#2658 */ mgcp_codec_reset_all(conn); rc = mgcp_codec_add(conn, 0, NULL, NULL); if (rc != 0) goto error; } /* Try to find an destination RTP connection that we can include in the codec decision. */ conn_dst = mgcp_find_dst_conn(conn->conn); if (conn_dst && conn_dst->type == MGCP_CONN_TYPE_RTP) conn_dst_rtp = &conn_dst->u.rtp; else conn_dst_rtp = NULL; /* Make codec decision */ if (mgcp_codec_decide(conn, conn_dst_rtp) != 0) goto error; return 0; error: LOGPCONN(conn->conn, DLMGCP, LOGL_ERROR, "%s: codec negotiation failure\n", cmd); /* See also RFC 3661: Codec negotiation failure */ return 534; } static bool parse_x_osmo_ign(struct mgcp_endpoint *endp, char *line) { char *saveptr = NULL; if (strncasecmp(line, MGCP_X_OSMO_IGN_HEADER, strlen(MGCP_X_OSMO_IGN_HEADER))) return false; line += strlen(MGCP_X_OSMO_IGN_HEADER); while (1) { char *token = strtok_r(line, " ", &saveptr); line = NULL; if (!token) break; if (!strcasecmp(token, "C")) endp->x_osmo_ign |= MGCP_X_OSMO_IGN_CALLID; else LOGPENDP(endp, DLMGCP, LOGL_ERROR, "received unknown X-Osmo-IGN item '%s'\n", token); } return true; } /* CRCX command handler, processes the received command */ static struct msgb *handle_create_con(struct mgcp_request_data *rq) { struct mgcp_parse_data *pdata = rq->pdata; struct mgcp_trunk *trunk = rq->trunk; struct mgcp_endpoint *endp = rq->endp; struct rate_ctr_group *rate_ctrs; int error_code = 400; const char *local_options = NULL; const char *callid = NULL; const char *mode = NULL; char *line; int have_sdp = 0, remote_osmux_cid = -2; struct mgcp_conn_rtp *conn = NULL; struct mgcp_conn *_conn = NULL; char conn_name[512]; int rc; LOGPENDP(endp, DLMGCP, LOGL_NOTICE, "CRCX: creating new connection ...\n"); if (rq->null_endp) { /* trunk not available so rate_ctr aren't available either. */ LOGP(DLMGCP, LOGL_ERROR, "CRCX: Not allowed in 'null' endpoint!\n"); return create_err_response(pdata->cfg, NULL, 502, "CRCX", pdata->trans); } rate_ctrs = trunk->ratectr.mgcp_crcx_ctr_group; /* we must have a free ep */ if (!endp) { rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_CRCX_FAIL_AVAIL)); LOGPENDP(endp, DLMGCP, LOGL_ERROR, "CRCX: no free endpoints available!\n"); return create_err_response(rq->trunk, NULL, 403, "CRCX", pdata->trans); } if (!mgcp_endp_avail(endp)) { rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_CRCX_FAIL_AVAIL)); LOGPENDP(endp, DLMGCP, LOGL_ERROR, "CRCX: selected endpoint not available!\n"); return create_err_response(rq->trunk, NULL, 501, "CRCX", pdata->trans); } /* parse CallID C: and LocalParameters L: */ for_each_line(line, pdata->save) { if (!mgcp_check_param(endp, trunk, line)) continue; switch (toupper(line[0])) { case 'L': local_options = (const char *)line + 3; break; case 'C': callid = (const char *)line + 3; break; case 'I': /* It is illegal to send a connection identifier * together with a CRCX, the MGW will assign the * connection identifier by itself on CRCX */ rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_CRCX_FAIL_BAD_ACTION)); return create_err_response(rq->trunk, NULL, 523, "CRCX", pdata->trans); break; case 'M': mode = (const char *)line + 3; break; case 'X': if (strncasecmp("Osmux: ", line + 2, strlen("Osmux: ")) == 0) { /* If osmux is disabled, just skip setting it up */ if (rq->endp->trunk->cfg->osmux.usage == OSMUX_USAGE_OFF) break; remote_osmux_cid = mgcp_osmux_setup(endp, line); break; } if (parse_x_osmo_ign(endp, line)) break; /* Ignore unknown X-headers */ break; case '\0': have_sdp = 1; goto mgcp_header_done; default: LOGPENDP(endp, DLMGCP, LOGL_NOTICE, "CRCX: unhandled option: '%c'/%d\n", *line, *line); rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_CRCX_FAIL_UNHANDLED_PARAM)); return create_err_response(rq->trunk, NULL, 539, "CRCX", pdata->trans); break; } } mgcp_header_done: /* Check parameters */ if (!callid) { LOGPENDP(endp, DLMGCP, LOGL_ERROR, "CRCX: insufficient parameters, missing callid\n"); rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_CRCX_FAIL_MISSING_CALLID)); return create_err_response(endp, endp, 516, "CRCX", pdata->trans); } if (!mode) { LOGPENDP(endp, DLMGCP, LOGL_ERROR, "CRCX: insufficient parameters, missing mode\n"); rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_CRCX_FAIL_INVALID_MODE)); return create_err_response(endp, endp, 517, "CRCX", pdata->trans); } /* Check if we are able to accept the creation of another connection */ if (endp->type->max_conns > 0 && llist_count(&endp->conns) >= endp->type->max_conns) { LOGPENDP(endp, DLMGCP, LOGL_ERROR, "CRCX: endpoint full, max. %i connections allowed!\n", endp->type->max_conns); if (trunk->force_realloc) { /* There is no more room for a connection, make some * room by blindly tossing the oldest of the two two * connections */ mgcp_conn_free_oldest(endp); } else { /* There is no more room for a connection, leave * everything as it is and return with an error */ rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_CRCX_FAIL_LIMIT_EXCEEDED)); return create_err_response(endp, endp, 540, "CRCX", pdata->trans); } } /* Check if this endpoint already serves a call, if so, check if the * callids match up so that we are sure that this is our call */ if (endp->callid && mgcp_verify_call_id(endp, callid)) { LOGPENDP(endp, DLMGCP, LOGL_ERROR, "CRCX: already seized by other call (%s)\n", endp->callid); if (trunk->force_realloc) /* This is not our call, toss everything by releasing * the entire endpoint. (rude!) */ mgcp_endp_release(endp); else { /* This is not our call, leave everything as it is and * return with an error. */ rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_CRCX_FAIL_UNKNOWN_CALLID)); return create_err_response(endp, endp, 400, "CRCX", pdata->trans); } } if (!endp->callid) { /* Claim endpoint resources. This will also set the callid, * creating additional connections will only be possible if * the callid matches up (see above). */ rc = mgcp_endp_claim(endp, callid); if (rc != 0) { rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_CRCX_FAIL_CLAIM)); return create_err_response(endp, endp, 502, "CRCX", pdata->trans); } } snprintf(conn_name, sizeof(conn_name), "%s", callid); _conn = mgcp_conn_alloc(trunk->endpoints, endp, MGCP_CONN_TYPE_RTP, conn_name); if (!_conn) { LOGPENDP(endp, DLMGCP, LOGL_ERROR, "CRCX: unable to allocate RTP connection\n"); rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_CRCX_FAIL_ALLOC_CONN)); goto error2; } conn = mgcp_conn_get_rtp(endp, _conn->id); OSMO_ASSERT(conn); if (mgcp_parse_conn_mode(mode, endp, conn->conn) != 0) { error_code = 517; rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_CRCX_FAIL_INVALID_MODE)); goto error2; } /* If X-Osmux (remote CID) was received (-1 is wilcard), alloc next avail CID as local CID */ if (remote_osmux_cid >= -1) { if (osmux_init_conn(conn) < 0) { rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_CRCX_FAIL_NO_OSMUX)); goto error2; } if (remote_osmux_cid >= 0) { conn->osmux.remote_cid_present = true; conn->osmux.remote_cid = remote_osmux_cid; } } else if (endp->trunk->cfg->osmux.usage == OSMUX_USAGE_ONLY) { LOGPCONN(_conn, DLMGCP, LOGL_ERROR, "CRCX: osmux only and no osmux offered\n"); rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_CRCX_FAIL_NO_OSMUX)); goto error2; } /* Set local connection options, if present */ if (local_options) { rc = set_local_cx_options(trunk->endpoints, &endp->local_options, local_options); if (rc != 0) { LOGPCONN(_conn, DLMGCP, LOGL_ERROR, "CRCX: invalid local connection options!\n"); error_code = rc; rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_CRCX_FAIL_INVALID_CONN_OPTIONS)); goto error2; } } /* Handle codec information and decide for a suitable codec */ rc = handle_codec_info(conn, rq, have_sdp, true); mgcp_codec_summary(conn); if (rc) { error_code = rc; rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_CRCX_FAIL_CODEC_NEGOTIATION)); goto error2; } /* Upgrade the conn type RTP_DEFAULT->RTP_IUUP if needed based on requested codec: */ /* TODO: "codec" probably needs to be moved from endp to conn */ if (conn->type == MGCP_RTP_DEFAULT && strcmp(conn->end.codec->subtype_name, "VND.3GPP.IUFP") == 0) { rc = mgcp_conn_iuup_init(conn); } if (pdata->cfg->force_ptime) { conn->end.packet_duration_ms = pdata->cfg->force_ptime; conn->end.force_output_ptime = 1; } mgcp_rtp_end_config(endp, 0, &conn->end); /* check connection mode setting */ if (conn->conn->mode != MGCP_CONN_LOOPBACK && conn->conn->mode != MGCP_CONN_RECV_ONLY && osmo_sockaddr_port(&conn->end.addr.u.sa) == 0) { LOGPCONN(_conn, DLMGCP, LOGL_ERROR, "CRCX: selected connection mode type requires an opposite end!\n"); error_code = 527; rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_CRCX_FAIL_NO_REMOTE_CONN_DESC)); goto error2; } /* Find a local address for conn based on policy and initial SDP remote information, then find a free port for it */ if (mgcp_get_local_addr(conn->end.local_addr, conn) < 0) { rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_CRCX_FAIL_BIND_PORT)); goto error2; } if (allocate_port(endp, conn) != 0) { rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_CRCX_FAIL_BIND_PORT)); goto error2; } if (setup_rtp_processing(endp, conn) != 0) { LOGPCONN(_conn, DLMGCP, LOGL_ERROR, "CRCX: could not start RTP processing!\n"); rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_CRCX_FAIL_START_RTP)); goto error2; } /* Notify Osmux conn that CRCX was received */ if (mgcp_conn_rtp_is_osmux(conn)) { if (conn_osmux_event_rx_crcx_mdcx(conn) < 0) { LOGPCONN(conn->conn, DLMGCP, LOGL_ERROR, "CRCX: Osmux handling failed!\n"); goto error2; } } LOGPCONN(conn->conn, DLMGCP, LOGL_DEBUG, "CRCX: Creating connection: port: %u\n", conn->end.local_port); /* Send dummy packet, see also comments in mgcp_keepalive_timer_cb() */ OSMO_ASSERT(trunk->keepalive_interval >= MGCP_KEEPALIVE_ONCE); if (conn->conn->mode & MGCP_CONN_RECV_ONLY && trunk->keepalive_interval != MGCP_KEEPALIVE_NEVER) send_dummy(endp, conn); LOGPCONN(_conn, DLMGCP, LOGL_NOTICE, "CRCX: connection successfully created\n"); rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_CRCX_SUCCESS)); mgcp_endp_update(endp); /* NOTE: Only in the virtual trunk we allow dynamic endpoint names */ bool add_epname = rq->wildcarded && trunk->trunk_type == MGCP_TRUNK_VIRTUAL; return create_response_with_sdp(endp, conn, "CRCX", pdata->trans, add_epname, true); error2: mgcp_endp_release(endp); LOGPENDP(endp, DLMGCP, LOGL_NOTICE, "CRCX: unable to create connection\n"); return create_err_response(endp, endp, error_code, "CRCX", pdata->trans); } /* MDCX command handler, processes the received command */ static struct msgb *handle_modify_con(struct mgcp_request_data *rq) { struct mgcp_parse_data *pdata = rq->pdata; struct mgcp_trunk *trunk = rq->trunk; struct mgcp_endpoint *endp = rq->endp; struct rate_ctr_group *rate_ctrs; char new_local_addr[INET6_ADDRSTRLEN]; int error_code = 500; int silent = 0; int have_sdp = 0; char *line; const char *local_options = NULL; const char *mode = NULL; struct mgcp_conn_rtp *conn = NULL; const char *conn_id = NULL; int remote_osmux_cid = -2; int rc; LOGPENDP(endp, DLMGCP, LOGL_NOTICE, "MDCX: modifying existing connection ...\n"); if (rq->null_endp) { /* trunk not available so rate_ctr aren't available either. */ LOGP(DLMGCP, LOGL_ERROR, "MDCX: Not allowed in 'null' endpoint!\n"); return create_err_response(pdata->cfg, NULL, 502, "MDCX", pdata->trans); } rate_ctrs = trunk->ratectr.mgcp_mdcx_ctr_group; /* Prohibit wildcarded requests */ if (rq->wildcarded) { LOGPENDP(endp, DLMGCP, LOGL_ERROR, "MDCX: wildcarded endpoint names not supported.\n"); rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_MDCX_FAIL_WILDCARD)); return create_err_response(rq->trunk, endp, 507, "MDCX", pdata->trans); } if (!endp || !mgcp_endp_avail(endp)) { rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_MDCX_FAIL_AVAIL)); LOGPENDP(endp, DLMGCP, LOGL_ERROR, "MDCX: selected endpoint not available!\n"); return create_err_response(rq->trunk, NULL, 501, "MDCX", pdata->trans); } if (llist_count(&endp->conns) <= 0) { LOGPENDP(endp, DLMGCP, LOGL_ERROR, "MDCX: endpoint is not holding a connection.\n"); rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_MDCX_FAIL_NO_CONN)); return create_err_response(endp, endp, 400, "MDCX", pdata->trans); } for_each_line(line, pdata->save) { if (!mgcp_check_param(endp, trunk, line)) continue; switch (toupper(line[0])) { case 'C': if (mgcp_verify_call_id(endp, line + 3) != 0) { rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_MDCX_FAIL_INVALID_CALLID)); error_code = 516; goto error3; } break; case 'I': conn_id = (const char *)line + 3; if ((error_code = mgcp_verify_ci(endp, conn_id))) { rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_MDCX_FAIL_INVALID_CONNID)); goto error3; } break; case 'L': local_options = (const char *)line + 3; break; case 'M': mode = (const char *)line + 3; break; case 'Z': silent = strcasecmp("noanswer", line + 3) == 0; break; case 'X': if (strncasecmp("Osmux: ", line + 2, strlen("Osmux: ")) == 0) { /* If osmux is disabled, just skip setting it up */ if (endp->trunk->cfg->osmux.usage == OSMUX_USAGE_OFF) break; remote_osmux_cid = mgcp_osmux_setup(endp, line); break; } /* Ignore unknown X-headers */ break; case '\0': have_sdp = 1; goto mgcp_header_done; break; default: LOGPENDP(endp, DLMGCP, LOGL_NOTICE, "MDCX: Unhandled MGCP option: '%c'/%d\n", line[0], line[0]); rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_MDCX_FAIL_UNHANDLED_PARAM)); return create_err_response(rq->trunk, NULL, 539, "MDCX", pdata->trans); break; } } mgcp_header_done: if (!conn_id) { LOGPENDP(endp, DLMGCP, LOGL_ERROR, "MDCX: insufficient parameters, missing ci (connectionIdentifier)\n"); rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_MDCX_FAIL_NO_CONNID)); return create_err_response(endp, endp, 515, "MDCX", pdata->trans); } conn = mgcp_conn_get_rtp(endp, conn_id); if (!conn) { rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_MDCX_FAIL_CONN_NOT_FOUND)); return create_err_response(endp, endp, 400, "MDCX", pdata->trans); } mgcp_conn_watchdog_kick(conn->conn); if (mode) { if (mgcp_parse_conn_mode(mode, endp, conn->conn) != 0) { rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_MDCX_FAIL_INVALID_MODE)); error_code = 517; goto error3; } } else conn->conn->mode = conn->conn->mode_orig; /* Set local connection options, if present */ if (local_options) { rc = set_local_cx_options(trunk->endpoints, &endp->local_options, local_options); if (rc != 0) { LOGPCONN(conn->conn, DLMGCP, LOGL_ERROR, "MDCX: invalid local connection options!\n"); error_code = rc; rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_MDCX_FAIL_INVALID_CONN_OPTIONS)); goto error3; } } /* Handle codec information and decide for a suitable codec */ rc = handle_codec_info(conn, rq, have_sdp, false); mgcp_codec_summary(conn); if (rc) { error_code = rc; goto error3; } /* Upgrade the conn type RTP_DEFAULT->RTP_IUUP if needed based on requested codec: */ /* TODO: "codec" probably needs to be moved from endp to conn */ if (conn->type == MGCP_RTP_DEFAULT && strcmp(conn->end.codec->subtype_name, "VND.3GPP.IUFP") == 0) rc = mgcp_conn_iuup_init(conn); /* check connection mode setting */ if (conn->conn->mode != MGCP_CONN_LOOPBACK && conn->conn->mode != MGCP_CONN_RECV_ONLY && !mgcp_rtp_end_remote_addr_available(&conn->end)) { LOGPCONN(conn->conn, DLMGCP, LOGL_ERROR, "MDCX: selected connection mode type requires an opposite end!\n"); error_code = 527; rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_MDCX_FAIL_NO_REMOTE_CONN_DESC)); goto error3; } if (mgcp_conn_rtp_is_osmux(conn)) { OSMO_ASSERT(conn->osmux.local_cid_allocated); if (remote_osmux_cid < -1) { LOGPCONN(conn->conn, DLMGCP, LOGL_ERROR, "MDCX: Failed to parse Osmux CID!\n"); goto error3; } else if (remote_osmux_cid == -1) { LOGPCONN(conn->conn, DLMGCP, LOGL_ERROR, "MDCX: wilcard in MDCX is not supported!\n"); goto error3; } else if (conn->osmux.remote_cid_present && remote_osmux_cid != conn->osmux.remote_cid) { LOGPCONN(conn->conn, DLMGCP, LOGL_ERROR, "MDCX: changing already allocated CID is not supported!\n"); goto error3; } else { conn->osmux.remote_cid_present = true; conn->osmux.remote_cid = remote_osmux_cid; if (conn_osmux_event_rx_crcx_mdcx(conn) < 0) { LOGPCONN(conn->conn, DLMGCP, LOGL_ERROR, "MDCX: Osmux handling failed!\n"); goto error3; } } } /* MDCX may have provided a new remote address, which means we may need to update our announced IP addr and re-bind our local end. This can happen for instance if MGW initially provided an IPv4 during CRCX ACK, and now MDCX tells us the remote has an IPv6 address. */ if (mgcp_get_local_addr(new_local_addr, conn) < 0) { rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_CRCX_FAIL_BIND_PORT)); goto error3; } if (strcmp(new_local_addr, conn->end.local_addr)) { osmo_strlcpy(conn->end.local_addr, new_local_addr, sizeof(conn->end.local_addr)); mgcp_free_rtp_port(&conn->end); if (allocate_port(endp, conn) != 0) { rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_CRCX_FAIL_BIND_PORT)); goto error3; } } if (setup_rtp_processing(endp, conn) != 0) { rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_MDCX_FAIL_START_RTP)); goto error3; } mgcp_rtp_end_config(endp, 1, &conn->end); /* modify */ LOGPCONN(conn->conn, DLMGCP, LOGL_DEBUG, "MDCX: modified conn:%s\n", mgcp_conn_dump(conn->conn)); /* Send dummy packet, see also comments in mgcp_keepalive_timer_cb() */ OSMO_ASSERT(trunk->keepalive_interval >= MGCP_KEEPALIVE_ONCE); if (conn->conn->mode & MGCP_CONN_RECV_ONLY && trunk->keepalive_interval != MGCP_KEEPALIVE_NEVER) send_dummy(endp, conn); rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_MDCX_SUCCESS)); if (silent) goto out_silent; LOGPCONN(conn->conn, DLMGCP, LOGL_NOTICE, "MDCX: connection successfully modified\n"); mgcp_endp_update(endp); return create_response_with_sdp(endp, conn, "MDCX", pdata->trans, false, false); error3: return create_err_response(endp, endp, error_code, "MDCX", pdata->trans); out_silent: LOGPENDP(endp, DLMGCP, LOGL_DEBUG, "MDCX: silent exit\n"); return NULL; } /* DLCX command handler, processes the received command */ static struct msgb *handle_delete_con(struct mgcp_request_data *rq) { struct mgcp_parse_data *pdata = rq->pdata; struct mgcp_trunk *trunk = rq->trunk; struct mgcp_endpoint *endp = rq->endp; struct rate_ctr_group *rate_ctrs; int error_code = 400; int silent = 0; char *line; char stats[1048]; const char *conn_id = NULL; struct mgcp_conn_rtp *conn = NULL; unsigned int i; /* NOTE: In this handler we can not take it for granted that the endp * pointer will be populated, however a trunk is always guaranteed (except for 'null' endp). */ LOGPEPTR(endp, trunk, DLMGCP, LOGL_NOTICE, "DLCX: deleting connection(s) ...\n"); if (rq->null_endp) { /* trunk not available so rate_ctr aren't available either. */ LOGP(DLMGCP, LOGL_ERROR, "DLCX: Not allowed in 'null' endpoint!\n"); return create_err_response(pdata->cfg, NULL, 502, "DLCX", pdata->trans); } rate_ctrs = trunk->ratectr.mgcp_dlcx_ctr_group; if (endp && !mgcp_endp_avail(endp)) { rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_DLCX_FAIL_AVAIL)); LOGPENDP(endp, DLMGCP, LOGL_ERROR, "DLCX: selected endpoint not available!\n"); return create_err_response(rq->trunk, NULL, 501, "DLCX", pdata->trans); } if (endp && !rq->wildcarded && llist_empty(&endp->conns)) { LOGPENDP(endp, DLMGCP, LOGL_ERROR, "DLCX: endpoint is not holding a connection.\n"); rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_DLCX_FAIL_NO_CONN)); return create_err_response(endp, endp, 515, "DLCX", pdata->trans); } /* Handle wildcarded DLCX that refers to the whole trunk. This means * that we walk over all endpoints on the trunk in order to drop all * connections on the trunk. (see also RFC3435 Annex F.7) */ if (rq->wildcarded) { int num_conns = 0; for (i = 0; i < trunk->number_endpoints; i++) { num_conns += llist_count(&trunk->endpoints[i]->conns); mgcp_endp_release(trunk->endpoints[i]); } rate_ctr_add(rate_ctr_group_get_ctr(rate_ctrs, MGCP_DLCX_SUCCESS), num_conns); return create_ok_response(trunk, NULL, 200, "DLCX", pdata->trans); } for_each_line(line, pdata->save) { if (!mgcp_check_param(endp, trunk, line)) continue; switch (toupper(line[0])) { case 'C': /* If we have no endpoint, but a call id in the request, then this request cannot be handled */ if (!endp) { LOGPTRUNK(trunk, DLMGCP, LOGL_NOTICE, "cannot handle requests with call-id (C) without endpoint -- abort!"); rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_DLCX_FAIL_UNHANDLED_PARAM)); return create_err_response(rq->trunk, NULL, 539, "DLCX", pdata->trans); } if (mgcp_verify_call_id(endp, line + 3) != 0) { error_code = 516; rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_DLCX_FAIL_INVALID_CALLID)); goto error3; } break; case 'I': /* If we have no endpoint, but a connection id in the request, then this request cannot be handled */ if (!endp) { LOGPTRUNK(trunk, DLMGCP, LOGL_NOTICE, "cannot handle requests with conn-id (I) without endpoint -- abort!"); rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_DLCX_FAIL_UNHANDLED_PARAM)); return create_err_response(rq->trunk, NULL, 539, "DLCX", pdata->trans); } conn_id = (const char *)line + 3; if ((error_code = mgcp_verify_ci(endp, conn_id))) { rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_DLCX_FAIL_INVALID_CONNID)); goto error3; } break; case 'Z': silent = strcasecmp("noanswer", line + 3) == 0; break; default: LOGPEPTR(endp, trunk, DLMGCP, LOGL_NOTICE, "DLCX: Unhandled MGCP option: '%c'/%d\n", line[0], line[0]); rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_DLCX_FAIL_UNHANDLED_PARAM)); return create_err_response(rq->trunk, NULL, 539, "DLCX", pdata->trans); break; } } /* The logic does not permit to go past this point without having the * the endp pointer populated. */ OSMO_ASSERT(endp); /* When no connection id is supplied, we will interpret this as a * wildcarded DLCX that refers to the selected endpoint. This means * that we drop all connections on that specific endpoint at once. * (See also RFC3435 Section F.7) */ if (!conn_id) { int num_conns = llist_count(&endp->conns); LOGPENDP(endp, DLMGCP, LOGL_NOTICE, "DLCX: missing ci (connectionIdentifier), will remove all connections (%d total) at once\n", num_conns); if (num_conns > 0) rate_ctr_add(rate_ctr_group_get_ctr(rate_ctrs, MGCP_DLCX_SUCCESS), num_conns); mgcp_endp_release(endp); /* Note: In this case we do not return any statistics, * as we assume that the client is not interested in * this case. */ return create_ok_response(endp, endp, 200, "DLCX", pdata->trans); } /* Find the connection */ conn = mgcp_conn_get_rtp(endp, conn_id); if (!conn) { rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_DLCX_FAIL_INVALID_CONNID)); goto error3; } /* save the statistics of the current connection */ mgcp_format_stats(stats, sizeof(stats), conn->conn); /* delete connection */ LOGPCONN(conn->conn, DLMGCP, LOGL_DEBUG, "DLCX: deleting conn:%s\n", mgcp_conn_dump(conn->conn)); mgcp_conn_free(endp, conn_id); LOGPENDP(endp, DLMGCP, LOGL_NOTICE, "DLCX: connection successfully deleted\n"); /* When all connections are closed, the endpoint will be released * in order to be ready to be used by another call. */ if (llist_count(&endp->conns) <= 0) { mgcp_endp_release(endp); LOGPENDP(endp, DLMGCP, LOGL_DEBUG, "DLCX: endpoint released\n"); } rate_ctr_inc(rate_ctr_group_get_ctr(rate_ctrs, MGCP_DLCX_SUCCESS)); if (silent) goto out_silent; return create_ok_resp_with_param(endp, endp, 250, "DLCX", pdata->trans, stats); error3: return create_err_response(endp, endp, error_code, "DLCX", pdata->trans); out_silent: LOGPENDP(endp, DLMGCP, LOGL_DEBUG, "DLCX: silent exit\n"); return NULL; } /* RSIP command handler, processes the received command */ static struct msgb *handle_rsip(struct mgcp_request_data *rq) { /* TODO: Also implement the resetting of a specific endpoint * to make mgcp_send_reset_ep() work. Currently this will call * mgcp_rsip_cb() in mgw_main.c, which sets reset_endpoints=1 * to make read_call_agent() reset all endpoints when called * next time. In order to selectively reset endpoints some * mechanism to distinguish which endpoint shall be resetted * is needed */ LOGP(DLMGCP, LOGL_NOTICE, "RSIP: resetting all endpoints ...\n"); if (rq->null_endp) { /* trunk not available so rate_ctr aren't available either. */ LOGP(DLMGCP, LOGL_ERROR, "RSIP: Not allowed in 'null' endpoint!\n"); return create_err_response(rq->pdata->cfg, NULL, 502, "RSIP", rq->pdata->trans); } if (rq->pdata->cfg->reset_cb) rq->pdata->cfg->reset_cb(rq->endp->trunk); return NULL; } static char extract_tone(const char *line) { const char *str = strstr(line, "D/"); if (!str) return CHAR_MAX; return str[2]; } /* This can request like DTMF detection and forward, fax detection... it * can also request when the notification should be send and such. We don't * do this right now. */ static struct msgb *handle_noti_req(struct mgcp_request_data *rq) { int res = 0; char *line; char tone = CHAR_MAX; LOGP(DLMGCP, LOGL_NOTICE, "RQNT: processing request for notification ...\n"); if (rq->null_endp) { /* trunk not available so rate_ctr aren't available either. */ LOGP(DLMGCP, LOGL_ERROR, "RQNT: Not allowed in 'null' endpoint!\n"); return create_err_response(rq->pdata->cfg, NULL, 502, "RQNT", rq->pdata->trans); } for_each_line(line, rq->pdata->save) { switch (toupper(line[0])) { case 'S': tone = extract_tone(line); break; } } /* we didn't see a signal request with a tone */ if (tone == CHAR_MAX) return create_ok_response(rq->endp, rq->endp, 200, "RQNT", rq->pdata->trans); if (rq->pdata->cfg->rqnt_cb) res = rq->pdata->cfg->rqnt_cb(rq->endp, tone); return res == 0 ? create_ok_response(rq->endp, rq->endp, 200, "RQNT", rq->pdata->trans) : create_err_response(rq->endp, rq->endp, res, "RQNT", rq->pdata->trans); } /* Connection keepalive timer, will take care that dummy packets are send * regularly, so that NAT connections stay open */ static void mgcp_keepalive_timer_cb(void *_trunk) { struct mgcp_trunk *trunk = _trunk; struct mgcp_conn *conn; int i; LOGP(DLMGCP, LOGL_DEBUG, "triggered trunk %d keepalive timer\n", trunk->trunk_nr); /* Do not accept invalid configuration values * valid is MGCP_KEEPALIVE_NEVER, MGCP_KEEPALIVE_ONCE and * values greater 0 */ OSMO_ASSERT(trunk->keepalive_interval >= MGCP_KEEPALIVE_ONCE); /* The dummy packet functionality has been disabled, we will exit * immediately, no further timer is scheduled, which means we will no * longer send dummy packets even when we did before */ if (trunk->keepalive_interval == MGCP_KEEPALIVE_NEVER) return; /* In cases where only one dummy packet is sent, we do not need * the timer since the functions that handle the CRCX and MDCX are * triggering the sending of the dummy packet. So we behave like in * the MGCP_KEEPALIVE_NEVER case */ if (trunk->keepalive_interval == MGCP_KEEPALIVE_ONCE) return; /* Send walk over all endpoints and send out dummy packets through * every connection present on each endpoint */ for (i = 0; i < trunk->number_endpoints; ++i) { struct mgcp_endpoint *endp = trunk->endpoints[i]; llist_for_each_entry(conn, &endp->conns, entry) { if (conn->type == MGCP_CONN_TYPE_RTP && conn->mode == MGCP_CONN_RECV_ONLY) send_dummy(endp, &conn->u.rtp); } } /* Schedule the keepalive timer for the next round */ LOGP(DLMGCP, LOGL_DEBUG, "rescheduling trunk %d keepalive timer\n", trunk->trunk_nr); osmo_timer_schedule(&trunk->keepalive_timer, trunk->keepalive_interval, 0); } void mgcp_trunk_set_keepalive(struct mgcp_trunk *trunk, int interval) { trunk->keepalive_interval = interval; osmo_timer_setup(&trunk->keepalive_timer, mgcp_keepalive_timer_cb, trunk); if (interval <= 0) osmo_timer_del(&trunk->keepalive_timer); else osmo_timer_schedule(&trunk->keepalive_timer, trunk->keepalive_interval, 0); } /* Free config, this function is automatically called by talloc_free when the configuration is freed. */ static int config_free_talloc_destructor(struct mgcp_config *cfg) { mgcp_ratectr_global_free(cfg); return 0; } /*! allocate configuration with default values. * (called once at startup by main function) */ struct mgcp_config *mgcp_config_alloc(void) { /* FIXME: This is unrelated to the protocol, put this in some * appropiate place! */ struct mgcp_config *cfg; cfg = talloc_zero(NULL, struct mgcp_config); if (!cfg) { LOGP(DLMGCP, LOGL_FATAL, "Failed to allocate config.\n"); return NULL; } osmo_strlcpy(cfg->domain, "mgw", sizeof(cfg->domain)); cfg->net_ports.lock = (pthread_mutex_t)PTHREAD_MUTEX_INITIALIZER; cfg->net_ports.range_start = RTP_PORT_DEFAULT_RANGE_START; cfg->net_ports.range_end = RTP_PORT_DEFAULT_RANGE_END; cfg->net_ports.last_port = cfg->net_ports.range_start; cfg->source_port = 2427; osmo_strlcpy(cfg->source_addr, "0.0.0.0", sizeof(cfg->source_addr)); cfg->rtp_processing_cb = &mgcp_rtp_processing_default; cfg->setup_rtp_processing_cb = &mgcp_setup_rtp_processing_default; INIT_LLIST_HEAD(&cfg->trunks); /* Allocate virtual trunk */ if (!mgcp_trunk_alloc(cfg, MGCP_TRUNK_VIRTUAL, MGCP_VIRT_TRUNK_ID)) { talloc_free(cfg); return NULL; } mgcp_ratectr_global_alloc(cfg); talloc_set_destructor(cfg, config_free_talloc_destructor); return cfg; } static int send_agent(struct mgcp_config *cfg, const char *buf, int len) { return write(cfg->gw_fd.bfd.fd, buf, len); } /*! Reset all endpoints by sending RSIP message to self. * (called by VTY) * \param[in] endp trunk endpoint * \param[in] endpoint number * \returns 0 on success, -1 on error */ int mgcp_send_reset_all(struct mgcp_config *cfg) { char buf[MGCP_ENDPOINT_MAXLEN + 128]; int len; int rc; len = snprintf(buf, sizeof(buf), "RSIP 1 *@%s MGCP 1.0\r\n", cfg->domain); if (len < 0) return -1; rc = send_agent(cfg, buf, len); if (rc <= 0) return -1; return 0; } /*! Reset a single endpoint by sending RSIP message to self. * (called by VTY) * \param[in] endp to reset * \returns 0 on success, -1 on error */ int mgcp_send_reset_ep(struct mgcp_endpoint *endp) { char buf[MGCP_ENDPOINT_MAXLEN + 128]; int len; int rc; len = snprintf(buf, sizeof(buf), "RSIP 39 %s MGCP 1.0\r\n", endp->name); if (len < 0) return -1; rc = send_agent(endp->trunk->cfg, buf, len); if (rc <= 0) return -1; return 0; }