/* mgcp_utils - common functions to setup an MGCP connection */ /* (C) 2016 by sysmocom s.f.m.c. GmbH * All Rights Reserved * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 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 General Public License for more details. * * You should have received a copy of the GNU 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 #ifndef OSMUX_CID_MAX #define OSMUX_CID_MAX 255 /* FIXME: use OSMUX_CID_MAX from libosmo-netif? */ #endif #define LOGPMGW(mgcp, level, fmt, args...) \ LOGP(DLMGCP, level, "MGW(%s) " fmt, mgcp_client_name(mgcp), ## args) /* Codec descripton for dynamic payload types (SDP) */ const struct value_string osmo_mgcpc_codec_names[] = { { CODEC_PCMU_8000_1, "PCMU/8000/1" }, { CODEC_GSM_8000_1, "GSM/8000/1" }, { CODEC_PCMA_8000_1, "PCMA/8000/1" }, { CODEC_G729_8000_1, "G729/8000/1" }, { CODEC_GSMEFR_8000_1, "GSM-EFR/8000/1" }, { CODEC_GSMHR_8000_1, "GSM-HR-08/8000/1" }, { CODEC_AMR_8000_1, "AMR/8000/1" }, { CODEC_AMRWB_16000_1, "AMR-WB/16000/1" }, { CODEC_IUFP, "VND.3GPP.IUFP/16000" }, { CODEC_CLEARMODE, "CLEARMODE/8000" }, { CODEC_COMPR_CSD, "VND.THEMWI.CCSD/8000" }, { 0, NULL }, }; /* Get encoding name from a full codec string e,g. * ("CODEC/8000/2" => returns "CODEC") */ static char *extract_codec_name(const char *str) { static char buf[64]; char *pos; if (!str) return NULL; osmo_strlcpy(buf, str, sizeof(buf)); pos = strchr(buf, '/'); if (pos) *pos = '\0'; return buf; } /*! Map a string to a codec. * \ptmap[in] str input string (e.g "GSM/8000/1", "GSM/8000" or "GSM") * \returns codec that corresponds to the given string representation. */ enum mgcp_codecs map_str_to_codec(const char *str) { unsigned int i; char *codec_name; char str_buf[64]; osmo_strlcpy(str_buf, extract_codec_name(str), sizeof(str_buf)); for (i = 0; i < ARRAY_SIZE(osmo_mgcpc_codec_names); i++) { codec_name = extract_codec_name(osmo_mgcpc_codec_names[i].str); if (!codec_name) continue; if (strcmp(codec_name, str_buf) == 0) return osmo_mgcpc_codec_names[i].value; } return -1; } /* Check the ptmap for illegal mappings */ static int check_ptmap(const struct ptmap *ptmap) { /* Check if there are mappings that leave the IANA assigned dynamic * payload type range. Under normal conditions such mappings should * not occur */ /* Its ok to have a 1:1 mapping in the statically defined * range, this won't hurt */ if (ptmap->codec == ptmap->pt) return 0; if (ptmap->codec < 96 || ptmap->codec > 127) goto error; if (ptmap->pt < 96 || ptmap->pt > 127) goto error; return 0; error: LOGP(DLMGCP, LOGL_ERROR, "ptmap contains illegal mapping: codec=%u maps to pt=%u\n", ptmap->codec, ptmap->pt); return -1; } /*! Map a codec to a payload type. * \ptmap[in] payload pointer to payload type map with specified payload types. * \ptmap[in] ptmap_len length of the payload type map. * \ptmap[in] codec the codec for which the payload type should be looked up. * \returns assigned payload type */ unsigned int map_codec_to_pt(const struct ptmap *ptmap, unsigned int ptmap_len, enum mgcp_codecs codec) { unsigned int i; /*! Note: If the payload type map is empty or the codec is not found * in the map, then a 1:1 mapping is performed. If the codec falls * into the statically defined range or if the mapping table isself * tries to map to the statically defined range, then the mapping * is also ignored and a 1:1 mapping is performed instead. */ /* we may return the codec directly since enum mgcp_codecs directly * corresponds to the statically assigned payload types */ if (codec < 96 || codec > 127) return codec; for (i = 0; i < ptmap_len; i++) { /* Skip illegal map entries */ if (check_ptmap(ptmap) == 0 && ptmap->codec == codec) return ptmap->pt; ptmap++; } /* If nothing is found, do not perform any mapping */ return codec; } /*! Map a payload type to a codec. * \ptmap[in] payload pointer to payload type map with specified payload types. * \ptmap[in] ptmap_len length of the payload type map. * \ptmap[in] payload type for which the codec should be looked up. * \returns codec that corresponds to the specified payload type */ enum mgcp_codecs map_pt_to_codec(struct ptmap *ptmap, unsigned int ptmap_len, unsigned int pt) { unsigned int i; /*! Note: If the payload type map is empty or the payload type is not * found in the map, then a 1:1 mapping is performed. If the payload * type falls into the statically defined range or if the mapping * table isself tries to map to the statically defined range, then * the mapping is also ignored and a 1:1 mapping is performed * instead. */ /* See also note in map_codec_to_pt() */ if (pt < 96 || pt > 127) return pt; for (i = 0; i < ptmap_len; i++) { if (check_ptmap(ptmap) == 0 && ptmap->pt == pt) return ptmap->codec; ptmap++; } /* If nothing is found, do not perform any mapping */ return pt; } static void _mgcp_client_conf_init(struct mgcp_client_conf *conf) { /* NULL and -1 default to MGCP_CLIENT_*_DEFAULT values */ *conf = (struct mgcp_client_conf){ .local_addr = NULL, .local_port = -1, .remote_addr = NULL, .remote_port = -1, .keepalive = { .timeout_sec = 0, /* disabled */ .req_interval_sec = 0, /* disabled */ .req_endpoint_name = MGCP_CLIENT_KEEPALIVE_DEFAULT_ENDP, }, }; INIT_LLIST_HEAD(&conf->reset_epnames); } /*! Allocate and initialize MGCP client configuration struct with default values. * \param[in] ctx talloc context to use as a parent during allocation. * * The returned struct can be freed using talloc_free(). */ struct mgcp_client_conf *mgcp_client_conf_alloc(void *ctx) { struct mgcp_client_conf *conf = talloc(ctx, struct mgcp_client_conf); _mgcp_client_conf_init(conf); return conf; } /*! Initialize MGCP client configuration struct with default values. * \param[out] conf Client configuration. * * This function is deprecated and should not be used, as it may break if size * of struct mgcp_client_conf changes in the future! */ void mgcp_client_conf_init(struct mgcp_client_conf *conf) { _mgcp_client_conf_init(conf); } static void mgcp_client_handle_response(struct mgcp_client *mgcp, struct mgcp_response_pending *pending, struct mgcp_response *response) { if (!pending) { LOGPMGW(mgcp, LOGL_ERROR, "Cannot handle NULL response\n"); return; } if (pending->response_cb) pending->response_cb(response, pending->priv); else LOGPMGW(mgcp, LOGL_DEBUG, "MGCP response ignored (NULL cb)\n"); talloc_free(pending); } static int mgcp_response_parse_head(struct mgcp_response *r, struct msgb *msg) { int comment_pos; char *end; if (mgcp_msg_terminate_nul(msg)) goto response_parse_failure; r->body = (char *)msg->data; if (sscanf(r->body, "%3d %u %n", &r->head.response_code, &r->head.trans_id, &comment_pos) != 2) goto response_parse_failure; osmo_strlcpy(r->head.comment, r->body + comment_pos, sizeof(r->head.comment)); end = strchr(r->head.comment, '\r'); if (!end) goto response_parse_failure; /* Mark the end of the comment */ *end = '\0'; return 0; response_parse_failure: LOGP(DLMGCP, LOGL_ERROR, "Failed to parse MGCP response header\n"); return -EINVAL; } /* TODO undup against mgcp_protocol.c:mgcp_check_param() */ static bool mgcp_line_is_valid(const char *line) { const size_t line_len = strlen(line); if (line[0] == '\0') return true; if (line_len < 2 || line[1] != '=') { LOGP(DLMGCP, LOGL_ERROR, "Wrong MGCP option format: '%s'\n", line); return false; } return true; } /* Parse a line like "m=audio 16002 RTP/AVP 98", extract port and payload types */ static int mgcp_parse_audio_port_pt(struct mgcp_response *r, char *line) { char *pt_str; char *pt_end; unsigned long int pt; unsigned int ptmap_len; unsigned int i; /* Extract port information */ if (sscanf(line, "m=audio %hu", &r->audio_port) != 1) goto response_parse_failure_port; if (r->audio_port == 0) goto response_parse_failure_port; /* Extract payload types */ line = strstr(line, "RTP/AVP "); if (!line) goto exit; /* Clear any previous entries before writing over r->ptmap */ r->ptmap_len = 0; /* Keep a local ptmap_len to show only the full list after parsing succeeded in whole. */ ptmap_len = 0; pt_str = strtok(line, " "); while (1) { pt_str = strtok(NULL, " "); if (!pt_str) break; errno = 0; pt = strtoul(pt_str, &pt_end, 0); if ((errno == ERANGE && pt == ULONG_MAX) || (errno && !pt) || pt_str == pt_end) { LOGP(DLMGCP, LOGL_ERROR, "SDP: cannot parse payload type number from '%s'\n", pt_str); goto response_parse_failure_pt; } /* PT is 7 bit field, higher values not allowed */ if (pt >> 7) { LOGP(DLMGCP, LOGL_ERROR, "SDP: payload type number out of range: %lu > 127\n", pt); goto response_parse_failure_pt; } /* Do not allow duplicate payload types */ for (i = 0; i < ptmap_len; i++) { if (r->ptmap[i].pt == pt) { LOGP(DLMGCP, LOGL_ERROR, "SDP: payload type number %lu listed twice\n", pt); goto response_parse_failure_pt; } } /* Do not allow excessive payload types */ if (ptmap_len >= ARRAY_SIZE(r->ptmap)) { LOGP(DLMGCP, LOGL_ERROR, "SDP: can parse only up to %zu payload type numbers\n", ARRAY_SIZE(r->ptmap)); goto response_parse_failure_pt; } /* Some payload type numbers imply a specific codec. For those, using the PT number as enum mgcp_codecs * yields the correct result. If no more specific information on the codec follows in "a=rtpmap:N" * lines, then this default number takes over. This only applies for PT below the dynamic range (<96). */ if (pt < 96) r->ptmap[ptmap_len].codec = pt; else r->ptmap[ptmap_len].codec = -1; r->ptmap[ptmap_len].pt = pt; ptmap_len++; } /* Parsing succeeded, publish all entries. */ r->ptmap_len = ptmap_len; exit: return 0; response_parse_failure_port: LOGP(DLMGCP, LOGL_ERROR, "Failed to parse SDP parameter port (%s)\n", line); return -EINVAL; response_parse_failure_pt: LOGP(DLMGCP, LOGL_ERROR, "Failed to parse SDP parameter payload types (%s)\n", line); return -EINVAL; } /* Parse an 'a=...' parameter */ static int mgcp_parse_audio_ptime_rtpmap(struct mgcp_response *r, const char *line) { unsigned int pt; unsigned int i; char codec_resp[64]; int rc; #define A_PTIME "a=ptime:" #define A_RTPMAP "a=rtpmap:" if (osmo_str_startswith(line, A_PTIME)) { if (sscanf(line, A_PTIME "%u", &r->ptime) != 1) { LOGP(DLMGCP, LOGL_ERROR, "Failed to parse SDP parameter, invalid ptime (%s)\n", line); return -EINVAL; } } else if (osmo_str_startswith(line, A_RTPMAP)) { if (sscanf(line, A_RTPMAP "%d %63s", &pt, codec_resp) != 2) { LOGP(DLMGCP, LOGL_ERROR, "Failed to parse SDP parameter, invalid rtpmap: %s\n", osmo_quote_str(line, -1)); return -EINVAL; } rc = map_str_to_codec(codec_resp); if (rc < 0) { LOGP(DLMGCP, LOGL_ERROR, "Failed to parse SDP parameter, can't parse codec in rtpmap: %s\n", osmo_quote_str(line, -1)); return -EINVAL; } /* Earlier, a line like "m=audio 16002 RTP/AVP 98 112 3" established the desired order of payloads, now * enrich it with actual codec information provided by "a=rtpmap:..." entries. * For each, find the entry with the right pt number and add the info there. */ for (i = 0; i < r->ptmap_len; i++) { if (r->ptmap[i].pt != pt) continue; r->ptmap[i].codec = rc; return 0; } /* No entry was found. This is an error in the MGCP protocol, but let's just add another entry * anyway, to not make it look like it was never there. */ LOGP(DLMGCP, LOGL_ERROR, "error in MGCP message: 'a=rtpmap:%u' has no matching entry in 'm=audio ... %u'\n", pt, pt); if (r->ptmap_len >= ARRAY_SIZE(r->ptmap)) { LOGP(DLMGCP, LOGL_ERROR, "cannot parse all codecs: can only store up to %zu rtpmap entries.\n", ARRAY_SIZE(r->ptmap)); return -ENOSPC; } r->ptmap[r->ptmap_len] = (struct ptmap){ .pt = pt, .codec = rc, }; r->ptmap_len++; } return 0; } /* Parse a line like "c=IN IP4 10.11.12.13" */ static int mgcp_parse_audio_ip(struct mgcp_response *r, const char *line) { struct in6_addr ip_test; bool is_ipv6; if (strncmp("c=IN IP", line, 7) != 0) goto response_parse_failure; line += 7; if (*line == '6') is_ipv6 = true; else if (*line == '4') is_ipv6 = false; else goto response_parse_failure; line++; if (*line != ' ') goto response_parse_failure; line++; /* Extract and check IP-Address */ if (is_ipv6) { /* 45 = INET6_ADDRSTRLEN -1 */ if (sscanf(line, "%45s", r->audio_ip) != 1) goto response_parse_failure; if (inet_pton(AF_INET6, r->audio_ip, &ip_test) != 1) goto response_parse_failure; } else { /* 15 = INET_ADDRSTRLEN -1 */ if (sscanf(line, "%15s", r->audio_ip) != 1) goto response_parse_failure; if (inet_pton(AF_INET, r->audio_ip, &ip_test) != 1) goto response_parse_failure; } return 0; response_parse_failure: LOGP(DLMGCP, LOGL_ERROR, "Failed to parse MGCP response header (audio ip)\n"); return -EINVAL; } /*! Extract OSMUX CID from an MGCP parameter line (string). * \param[in] line single parameter line from the MGCP message * \returns OSMUX CID, -1 wildcard, -2 on error * FIXME: This is a copy of function in mgcp_msg.c. Have some common.c file between both libs? */ static int mgcp_parse_osmux_cid(const char *line) { int osmux_cid; if (strcasecmp(line + 2, "Osmux: *") == 0) { LOGP(DLMGCP, LOGL_DEBUG, "Parsed wilcard Osmux CID\n"); return -1; } if (sscanf(line + 2 + 7, "%u", &osmux_cid) != 1) { LOGP(DLMGCP, LOGL_ERROR, "Failed parsing Osmux in MGCP msg line: %s\n", line); return -2; } if (osmux_cid > OSMUX_CID_MAX) { /* OSMUX_CID_MAX from libosmo-netif */ LOGP(DLMGCP, LOGL_ERROR, "Osmux ID too large: %u > %u\n", osmux_cid, OSMUX_CID_MAX); return -2; } LOGP(DLMGCP, LOGL_DEBUG, "MGW offered Osmux CID %u\n", osmux_cid); return osmux_cid; } /* A new section is marked by a double line break, check a few more * patterns as there may be variants */ static char *mgcp_find_section_end(char *string) { char *rc; rc = strstr(string, "\n\n"); if (rc) return rc + 2; rc = strstr(string, "\n\r\n\r"); if (rc) return rc + 4; rc = strstr(string, "\r\n\r\n"); if (rc) return rc + 4; return NULL; } /*! Parse body (SDP) parameters of the MGCP response * \param[in,out] r Response data * \returns 0 on success, -EINVAL on error. */ int mgcp_response_parse_params(struct mgcp_response *r) { char *line; int rc; char *data; char *data_ptr; /* Since this functions performs a destructive parsing, we create a * local copy of the body data */ OSMO_ASSERT(r->body); data = talloc_strdup(r, r->body); OSMO_ASSERT(data); /* Find beginning of the parameter (SDP) section */ data_ptr = mgcp_find_section_end(data); if (!data_ptr) { LOGP(DLMGCP, LOGL_DEBUG, "MGCP response contains no SDP parameters\n"); rc = 0; goto exit; } /* data_ptr now points to the beginning of the section-end-marker; for_each_non_empty_line() * skips any \r and \n characters for free, so we don't need to skip the marker. */ for_each_non_empty_line(line, data_ptr) { if (!mgcp_line_is_valid(line)) return -EINVAL; switch (line[0]) { case 'a': rc = mgcp_parse_audio_ptime_rtpmap(r, line); if (rc) goto exit; break; case 'm': rc = mgcp_parse_audio_port_pt(r, line); if (rc) goto exit; break; case 'c': rc = mgcp_parse_audio_ip(r, line); if (rc) goto exit; break; default: /* skip unhandled parameters */ break; } } rc = 0; exit: talloc_free(data); return rc; } /* Parse a line like "X: something" */ static int mgcp_parse_head_param(char *result, unsigned int result_len, char label, const char *line) { char label_string[4]; size_t rc; /* Detect empty parameters */ if (strlen(line) < 4) goto response_parse_failure; /* Check if the label matches */ snprintf(label_string, sizeof(label_string), "%c: ", label); if (memcmp(label_string, line, 3) != 0) goto response_parse_failure; /* Copy payload part of the string to destinations (the label string * is always 3 chars long) */ rc = osmo_strlcpy(result, line + 3, result_len); if (rc >= result_len) { LOGP(DLMGCP, LOGL_ERROR, "Failed to parse MGCP response (parameter label: %c):" " the received conn ID is too long: %zu, maximum is %u characters\n", label, rc, result_len - 1); return -ENOSPC; } return 0; response_parse_failure: LOGP(DLMGCP, LOGL_ERROR, "Failed to parse MGCP response (parameter label: %c)\n", label); return -EINVAL; } /* Parse MGCP parameters of the response */ static int parse_head_params(struct mgcp_response *r) { char *line; int rc = 0; OSMO_ASSERT(r->body); char *data; char *data_ptr; char *data_end; /* Since this functions performs a destructive parsing, we create a * local copy of the body data */ data = talloc_zero_size(r, strlen(r->body)+1); OSMO_ASSERT(data); data_ptr = data; osmo_strlcpy(data, r->body, strlen(r->body)); /* If there is an SDP body attached, prevent for_each_non_empty_line() * into running in there, we are not yet interested in the parameters * stored there. */ data_end = mgcp_find_section_end(data); if (data_end) *data_end = '\0'; for_each_non_empty_line(line, data_ptr) { switch (toupper(line[0])) { case 'Z': rc = mgcp_parse_head_param(r->head.endpoint, sizeof(r->head.endpoint), 'Z', line); if (rc) goto exit; /* A specific endpoint identifier returned by the MGW * must not contain any wildcard characters */ if (strstr(r->head.endpoint, "*") != NULL) { rc = -EINVAL; goto exit; } /* A specific endpoint identifier returned by the MGW * must contain an @ character */ if (strstr(r->head.endpoint, "@") == NULL) { rc = -EINVAL; goto exit; } break; case 'I': rc = mgcp_parse_head_param(r->head.conn_id, sizeof(r->head.conn_id), 'I', line); if (rc) goto exit; break; case 'X': if (strncasecmp("Osmux: ", line + 2, strlen("Osmux: ")) == 0) { rc = mgcp_parse_osmux_cid(line); if (rc < 0) { /* -1: we don't want wildcards in response. -2: error */ rc = -EINVAL; goto exit; } r->head.x_osmo_osmux_use = true; r->head.x_osmo_osmux_cid = (uint8_t) rc; rc = 0; break; } /* Ignore unknown X-headers */ break; default: /* skip unhandled parameters */ break; } } exit: talloc_free(data); return rc; } static struct mgcp_response_pending *mgcp_client_response_pending_get( struct mgcp_client *mgcp, mgcp_trans_id_t trans_id) { struct mgcp_response_pending *pending; llist_for_each_entry(pending, &mgcp->responses_pending, entry) { if (pending->trans_id == trans_id) { llist_del(&pending->entry); return pending; } } return NULL; } /* Feed an MGCP message into the receive processing. * Parse the head and call any callback registered for the transaction id found * in the MGCP message. This is normally called directly from the internal * mgcp_read_cb that reads from the socket connected to the MGCP gateway. This * function is published mainly to be able to feed data from the test suite. */ int mgcp_client_rx(struct mgcp_client *mgcp, struct msgb *msg) { struct mgcp_response *r; struct mgcp_response_pending *pending; int rc; r = talloc_zero(mgcp, struct mgcp_response); OSMO_ASSERT(r); /* Re-arm keepalive timer if enabled */ if (OSMO_UNLIKELY(mgcp->conn_up == false)) { LOGPMGW(mgcp, LOGL_NOTICE, "MGCP link to MGW now considered UP\n"); mgcp->conn_up = true; } if (mgcp->actual.keepalive.timeout_sec > 0) osmo_timer_schedule(&mgcp->keepalive_rx_timer, mgcp->actual.keepalive.timeout_sec, 0); rc = mgcp_response_parse_head(r, msg); if (rc) { LOGPMGW(mgcp, LOGL_ERROR, "Cannot parse MGCP response (head)\n"); rc = 1; goto error; } LOGPMGW(mgcp, LOGL_DEBUG, "MGCP client: Rx %d %u %s\n", r->head.response_code, r->head.trans_id, r->head.comment); rc = parse_head_params(r); if (rc) { LOGPMGW(mgcp, LOGL_ERROR, "Cannot parse MGCP response (head parameters)\n"); rc = 1; goto error; } pending = mgcp_client_response_pending_get(mgcp, r->head.trans_id); if (!pending) { LOGPMGW(mgcp, LOGL_ERROR, "Cannot find matching MGCP transaction for trans_id %d\n", r->head.trans_id); rc = -ENOENT; goto error; } mgcp_client_handle_response(mgcp, pending, r); rc = 0; error: talloc_free(r); return rc; } static void mgcp_read_cb(struct osmo_io_fd *iofd, int res, struct msgb *msg) { struct mgcp_client *mgcp = osmo_iofd_get_data(iofd); if (res <= 0) { char errbuf[128] = ""; strerror_r(-res, errbuf, sizeof(errbuf)); LOGPMGW(mgcp, LOGL_ERROR, "Failed to read: %s: %d='%s'\n", osmo_iofd_get_name(iofd), res, errbuf); msgb_free(msg); return; } msg->l2h = msg->head; mgcp_client_rx(mgcp, msg); talloc_free(msg); } static int mgcp_do_write(struct mgcp_client *mgcp, struct msgb *msg) { int ret; LOGPMGW(mgcp, LOGL_DEBUG, "Tx MGCP: %s: len=%u '%s'...\n", osmo_iofd_get_name(mgcp->iofd), msg->len, osmo_escape_str((const char *)msg->data, OSMO_MIN(42, msg->len))); ret = osmo_iofd_write_msgb(mgcp->iofd, msg); if (ret < 0) msgb_free(msg); /* Re-arm the keepalive Tx timer: */ if (mgcp->actual.keepalive.req_interval_sec > 0) osmo_timer_schedule(&mgcp->keepalive_tx_timer, mgcp->actual.keepalive.req_interval_sec, 0); return ret; } static void mgcp_write_cb(struct osmo_io_fd *iofd, int res, struct msgb *msg) { struct mgcp_client *mgcp = osmo_iofd_get_data(iofd); if (OSMO_UNLIKELY(res != msg->len)) { char errbuf[128] = ""; strerror_r(-res, errbuf, sizeof(errbuf)); LOGPMGW(mgcp, LOGL_ERROR, "Failed to Tx MGCP: %s: %d='%s'; msg: len=%u '%s'...\n", osmo_iofd_get_name(mgcp->iofd), res, errbuf, msg->len, osmo_escape_str((const char *)msg->data, OSMO_MIN(42, msg->len))); } } static const char *_mgcp_client_name_append_domain(const struct mgcp_client *mgcp, const char *name) { static char endpoint[MGCP_ENDPOINT_MAXLEN]; int rc; rc = snprintf(endpoint, sizeof(endpoint), "%s@%s", name, mgcp_client_endpoint_domain(mgcp)); if (rc > sizeof(endpoint) - 1) { LOGPMGW(mgcp, LOGL_ERROR, "MGCP endpoint exceeds maximum length of %zu: '%s@%s'\n", sizeof(endpoint) - 1, name, mgcp_client_endpoint_domain(mgcp)); return NULL; } if (rc < 1) { LOGPMGW(mgcp, LOGL_ERROR, "Cannot compose MGCP endpoint name\n"); return NULL; } return endpoint; } /* Safely ignore the MGCP response to the DLCX sent via _mgcp_client_send_dlcx() */ static void _ignore_mgcp_response(struct mgcp_response *response, void *priv) { } /* Format DLCX message (fire and forget) and send it off to the MGW */ static void _mgcp_client_send_dlcx(struct mgcp_client *mgcp, const char *epname) { struct msgb *msgb_dlcx; struct mgcp_msg mgcp_msg_dlcx = { .verb = MGCP_VERB_DLCX, .presence = MGCP_MSG_PRESENCE_ENDPOINT, }; osmo_strlcpy(mgcp_msg_dlcx.endpoint, epname, sizeof(mgcp_msg_dlcx.endpoint)); msgb_dlcx = mgcp_msg_gen(mgcp, &mgcp_msg_dlcx); if (!msgb_dlcx) { LOGPMGW(mgcp, LOGL_ERROR, "Failed generating MGCP DLCX %s\n", epname); return; } mgcp_client_tx(mgcp, msgb_dlcx, &_ignore_mgcp_response, NULL); } /* Format AuditEndpoint message (fire and forget) and send it off to the MGW */ static void _mgcp_client_send_auep(struct mgcp_client *mgcp, const char *epname) { struct msgb *msgb_auep; struct mgcp_msg mgcp_msg_auep = { .verb = MGCP_VERB_AUEP, .presence = MGCP_MSG_PRESENCE_ENDPOINT, }; OSMO_STRLCPY_ARRAY(mgcp_msg_auep.endpoint, epname); msgb_auep = mgcp_msg_gen(mgcp, &mgcp_msg_auep); if (!msgb_auep) { LOGPMGW(mgcp, LOGL_ERROR, "Failed generating MGCP AUEP %s\n", epname); return; } mgcp_client_tx(mgcp, msgb_auep, &_ignore_mgcp_response, NULL); } static void mgcp_client_keepalive_tx_timer_cb(void *data) { struct mgcp_client *mgcp = (struct mgcp_client *)data; LOGPMGW(mgcp, LOGL_INFO, "Triggering keepalive MGCP request\n"); const char *epname = _mgcp_client_name_append_domain(mgcp, mgcp->actual.keepalive.req_endpoint_name); _mgcp_client_send_auep(mgcp, epname); /* Re-arm the timer: */ osmo_timer_schedule(&mgcp->keepalive_tx_timer, mgcp->actual.keepalive.req_interval_sec, 0); } static void mgcp_client_keepalive_rx_timer_cb(void *data) { struct mgcp_client *mgcp = (struct mgcp_client *)data; LOGPMGW(mgcp, LOGL_ERROR, "MGCP link to MGW now considered DOWN (keepalive timeout, more than %u seconds with no answer from MGW)\n", mgcp->actual.keepalive.timeout_sec); mgcp->conn_up = false; /* TODO: Potentially time out all ongoing transactions for that MGW. Maybe based on VTY cfg? */ } struct mgcp_client *mgcp_client_init(void *ctx, struct mgcp_client_conf *conf) { struct mgcp_client *mgcp; struct reset_ep *reset_ep; struct reset_ep *actual_reset_ep; mgcp = talloc_zero(ctx, struct mgcp_client); if (!mgcp) return NULL; INIT_LLIST_HEAD(&mgcp->responses_pending); mgcp->next_trans_id = 1; mgcp->actual.local_addr = conf->local_addr ? conf->local_addr : MGCP_CLIENT_LOCAL_ADDR_DEFAULT; mgcp->actual.local_port = conf->local_port > 0 ? (uint16_t)conf->local_port : MGCP_CLIENT_LOCAL_PORT_DEFAULT; mgcp->actual.remote_addr = conf->remote_addr ? conf->remote_addr : MGCP_CLIENT_REMOTE_ADDR_DEFAULT; mgcp->actual.remote_port = conf->remote_port >= 0 ? (uint16_t)conf->remote_port : MGCP_CLIENT_REMOTE_PORT_DEFAULT; if (osmo_strlcpy(mgcp->actual.endpoint_domain_name, conf->endpoint_domain_name, sizeof(mgcp->actual.endpoint_domain_name)) >= sizeof(mgcp->actual.endpoint_domain_name)) { LOGPMGW(mgcp, LOGL_ERROR, "MGCP client: endpoint domain name is too long, max length is %zu: '%s'\n", sizeof(mgcp->actual.endpoint_domain_name) - 1, conf->endpoint_domain_name); talloc_free(mgcp); return NULL; } LOGPMGW(mgcp, LOGL_NOTICE, "MGCP client: using endpoint domain '@%s'\n", mgcp_client_endpoint_domain(mgcp)); INIT_LLIST_HEAD(&mgcp->actual.reset_epnames); llist_for_each_entry(reset_ep, &conf->reset_epnames, list) { actual_reset_ep = talloc_memdup(mgcp, reset_ep, sizeof(*reset_ep)); llist_add_tail(&actual_reset_ep->list, &mgcp->actual.reset_epnames); } if (conf->description) mgcp->actual.description = talloc_strdup(mgcp, conf->description); memcpy(&mgcp->actual.keepalive, &conf->keepalive, sizeof(conf->keepalive)); osmo_timer_setup(&mgcp->keepalive_tx_timer, mgcp_client_keepalive_tx_timer_cb, mgcp); osmo_timer_setup(&mgcp->keepalive_rx_timer, mgcp_client_keepalive_rx_timer_cb, mgcp); return mgcp; } static const struct osmo_io_ops mgcp_clnt_ioops = { .read_cb = mgcp_read_cb, .write_cb = mgcp_write_cb, }; /*! Initialize client connection (opens socket) * \param[in,out] mgcp MGCP client descriptor. * \returns 0 on success, -EINVAL on error. */ int mgcp_client_connect(struct mgcp_client *mgcp) { int rc; struct reset_ep *reset_ep; const char *epname; bool some_dlcx_sent = false; if (!mgcp) { LOGPMGW(mgcp, LOGL_FATAL, "Client not initialized properly\n"); return -EINVAL; } rc = osmo_sock_init2(AF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, mgcp->actual.local_addr, mgcp->actual.local_port, mgcp->actual.remote_addr, mgcp->actual.remote_port, OSMO_SOCK_F_BIND | OSMO_SOCK_F_CONNECT); if (rc < 0) { LOGPMGW(mgcp, LOGL_FATAL, "Failed to initialize socket %s:%u -> %s:%u for MGW: %s\n", mgcp->actual.local_addr ? mgcp->actual.local_addr : "(any)", mgcp->actual.local_port, mgcp->actual.remote_addr ? mgcp->actual.local_addr : "(any)", mgcp->actual.remote_port, strerror(errno)); goto error_free; } mgcp->iofd = osmo_iofd_setup(mgcp, rc, osmo_sock_get_name2(rc), OSMO_IO_FD_MODE_READ_WRITE, &mgcp_clnt_ioops, mgcp); if (!mgcp->iofd) goto error_close_fd; LOGPMGW(mgcp, LOGL_INFO, "MGW connection: %s\n", osmo_iofd_get_name(mgcp->iofd)); osmo_iofd_register(mgcp->iofd, -1); osmo_iofd_set_alloc_info(mgcp->iofd, 4096, 128); osmo_iofd_set_txqueue_max_length(mgcp->iofd, 1024); /* If configured, send a DLCX message to the endpoints that are configured to * be reset on startup. Usually this is a wildcarded endpoint. */ llist_for_each_entry(reset_ep, &mgcp->actual.reset_epnames, list) { epname = _mgcp_client_name_append_domain(mgcp, reset_ep->name); LOGPMGW(mgcp, LOGL_INFO, "Sending DLCX to: %s\n", epname); _mgcp_client_send_dlcx(mgcp, epname); some_dlcx_sent = true; } if (mgcp->actual.keepalive.req_interval_sec > 0) { if (!some_dlcx_sent) { /* Attempt an immediate probe to find out if link is UP or DOWN: */ osmo_timer_schedule(&mgcp->keepalive_tx_timer, 0, 0); } /* else: keepalive_tx_timer was already scheduled (if needed) down in the stack during Tx DLCX above */ } else { /* Assume link is UP by default, so that this MGW can be selected: */ mgcp->conn_up = true; } if (mgcp->actual.keepalive.timeout_sec > 0) osmo_timer_schedule(&mgcp->keepalive_rx_timer, mgcp->actual.keepalive.timeout_sec, 0); return 0; error_close_fd: close(rc); error_free: return rc; } /*! DEPRECATED: Initialize client connection (opens socket) * \param[in,out] mgcp MGCP client descriptor. * \returns 0 on success, -EINVAL on error. */ int mgcp_client_connect2(struct mgcp_client *mgcp, unsigned int retry_n_ports) { return mgcp_client_connect(mgcp); } /*! Terminate client connection * \param[in,out] mgcp MGCP client descriptor. * \returns 0 on success, -EINVAL on error. */ void mgcp_client_disconnect(struct mgcp_client *mgcp) { if (!mgcp) { LOGP(DLMGCP, LOGL_FATAL, "MGCP client not initialized properly\n"); return; } /* Disarm keepalive Tx/Rx timer until next connect() */ osmo_timer_del(&mgcp->keepalive_rx_timer); osmo_timer_del(&mgcp->keepalive_tx_timer); mgcp->conn_up = false; osmo_iofd_txqueue_clear(mgcp->iofd); LOGPMGW(mgcp, LOGL_INFO, "MGCP association: %s -- closed!\n", osmo_iofd_get_name(mgcp->iofd)); osmo_iofd_free(mgcp->iofd); mgcp->iofd = NULL; } /*! Get the IP-Aaddress of the associated MGW as string. * \param[in] mgcp MGCP client descriptor. * \returns a pointer to the address string. */ const char *mgcp_client_remote_addr_str(struct mgcp_client *mgcp) { return mgcp->actual.remote_addr; } /*! Get the IP-Port of the associated MGW. * \param[in] mgcp MGCP client descriptor. * \returns port number. */ uint16_t mgcp_client_remote_port(struct mgcp_client *mgcp) { return mgcp->actual.remote_port; } /*! Get the IP-Address of the associated MGW as its numeric representation. * DEPRECATED, DON'T USE. * \param[in] mgcp MGCP client descriptor. * \returns IP-Address as 32 bit integer (network byte order) */ uint32_t mgcp_client_remote_addr_n(struct mgcp_client *mgcp) { return 0; } /* To compose endpoint names, usually for CRCX, use this as domain name. * For example, snprintf("rtpbridge\*@%s", mgcp_client_endpoint_domain(mgcp)). */ const char *mgcp_client_endpoint_domain(const struct mgcp_client *mgcp) { return mgcp->actual.endpoint_domain_name[0] ? mgcp->actual.endpoint_domain_name : "mgw"; } /*! Compose endpoint name for a wildcarded request to the virtual trunk * \param[in] mgcp MGCP client descriptor. * \returns string containing the endpoint name (e.g. rtpbridge\*@mgw) */ const char *mgcp_client_rtpbridge_wildcard(const struct mgcp_client *mgcp) { return _mgcp_client_name_append_domain(mgcp, "rtpbridge/*"); } /*! Compose endpoint name for an E1 endpoint. * \param[in] ctx talloc context. * \param[in] mgcp MGCP client descriptor. * \param[in] trunk_id id number of the E1 trunk (1-64). * \param[in] ts timeslot on the E1 trunk (1-31). * \param[in] rate bitrate used on the E1 trunk (e.g 16 for 16kbit). * \param[in] offset bit offset of the E1 subslot (e.g. 4 for the third 16k subslot). * \returns string containing the endpoint name (e.g. ds/e1-1/s-1/su16-4). */ const char *mgcp_client_e1_epname(void *ctx, const struct mgcp_client *mgcp, uint8_t trunk_id, uint8_t ts, uint8_t rate, uint8_t offset) { /* See also comment in libosmo-mgcp, mgcp_client.c, gen_e1_epname() */ const uint8_t valid_rates[] = { 64, 32, 32, 16, 16, 16, 16, 8, 8, 8, 8, 8, 8, 8, 8 }; const uint8_t valid_offsets[] = { 0, 0, 4, 0, 2, 4, 6, 0, 1, 2, 3, 4, 5, 6, 7 }; uint8_t i; bool rate_offs_valid = false; char *epname; epname = talloc_asprintf(ctx, "ds/e1-%u/s-%u/su%u-%u@%s", trunk_id, ts, rate, offset, mgcp_client_endpoint_domain(mgcp)); if (!epname) { LOGPMGW(mgcp, LOGL_ERROR, "Cannot compose MGCP e1-endpoint name!\n"); return NULL; } /* Check if the supplied rate/offset pair resembles a valid combination */ for (i = 0; i < sizeof(valid_rates); i++) { if (valid_rates[i] == rate && valid_offsets[i] == offset) rate_offs_valid = true; } if (!rate_offs_valid) { LOGPMGW(mgcp, LOGL_ERROR, "Cannot compose MGCP e1-endpoint name (%s), rate(%u)/offset(%u) combination is invalid!\n", epname, rate, offset); talloc_free(epname); return NULL; } /* An E1 line has a maximum of 32 timeslots, while the first (ts=0) is * reserverd for framing and alignment, so we can not use it here. */ if (ts == 0 || ts > NUM_E1_TS-1) { LOGPMGW(mgcp, LOGL_ERROR, "Cannot compose MGCP e1-endpoint name (%s), E1-timeslot number (%u) is invalid!\n", epname, ts); talloc_free(epname); return NULL; } return epname; } struct mgcp_response_pending *mgcp_client_pending_add(struct mgcp_client *mgcp, mgcp_trans_id_t trans_id, mgcp_response_cb_t response_cb, void *priv) { struct mgcp_response_pending *pending; pending = talloc_zero(mgcp, struct mgcp_response_pending); if (!pending) return NULL; pending->trans_id = trans_id; pending->response_cb = response_cb; pending->priv = priv; llist_add_tail(&pending->entry, &mgcp->responses_pending); return pending; } /* Send the MGCP message in msg to the MGW and handle a response with * response_cb. NOTE: the response_cb still needs to call * mgcp_response_parse_params(response) to get the parsed parameters -- to * potentially save some CPU cycles, only the head line has been parsed when * the response_cb is invoked. * Before the priv pointer becomes invalid, e.g. due to transaction timeout, * mgcp_client_cancel() needs to be called for this transaction. */ int mgcp_client_tx(struct mgcp_client *mgcp, struct msgb *msg, mgcp_response_cb_t response_cb, void *priv) { struct mgcp_response_pending *pending = NULL; mgcp_trans_id_t trans_id; int rc; trans_id = msg->cb[MSGB_CB_MGCP_TRANS_ID]; if (!trans_id) { LOGPMGW(mgcp, LOGL_ERROR, "Unset transaction id in mgcp send request\n"); talloc_free(msg); return -EINVAL; } /* Do not allocate a dummy 'mgcp_response_pending' entry */ if (response_cb != NULL) { pending = mgcp_client_pending_add(mgcp, trans_id, response_cb, priv); if (!pending) { talloc_free(msg); return -ENOMEM; } } if (msgb_l2len(msg) > 4096) { LOGPMGW(mgcp, LOGL_ERROR, "Cannot send, MGCP message too large: %u\n", msgb_l2len(msg)); msgb_free(msg); rc = -EINVAL; goto mgcp_tx_error; } rc = mgcp_do_write(mgcp, msg); if (rc) { LOGPMGW(mgcp, LOGL_FATAL, "Could not queue message to MGW\n"); goto mgcp_tx_error; } else LOGPMGW(mgcp, LOGL_DEBUG, "Queued %u bytes for MGW\n", msgb_l2len(msg)); return 0; mgcp_tx_error: if (!pending) return rc; /* Dequeue pending response, it's going to be free()d */ llist_del(&pending->entry); /* Pass NULL to response cb to indicate an error */ mgcp_client_handle_response(mgcp, pending, NULL); return rc; } /*! Cancel a pending transaction. * \param[in] mgcp MGCP client descriptor. * \param[in,out] trans_id Transaction id. * \returns 0 on success, -ENOENT on error. * * Should a priv pointer passed to mgcp_client_tx() become invalid, this function must be called. In * practical terms, if the caller of mgcp_client_tx() wishes to tear down a transaction without having * received a response this function must be called. The trans_id can be obtained by calling * mgcp_msg_trans_id() on the msgb produced by mgcp_msg_gen(). */ int mgcp_client_cancel(struct mgcp_client *mgcp, mgcp_trans_id_t trans_id) { struct mgcp_response_pending *pending = mgcp_client_response_pending_get(mgcp, trans_id); if (!pending) { /*! Note: it is not harmful to cancel a transaction twice. */ LOGPMGW(mgcp, LOGL_ERROR, "Cannot cancel, no such transaction: %u\n", trans_id); return -ENOENT; } LOGPMGW(mgcp, LOGL_DEBUG, "Canceled transaction %u\n", trans_id); talloc_free(pending); return 0; /*! We don't really need to clean up the wqueue: In all sane cases, the msgb has already been sent * out and is no longer in the wqueue. If it still is in the wqueue, then sending MGCP messages * per se is broken and the program should notice so by a full wqueue. Even if this was called * before we had a chance to send out the message and it is still going to be sent, we will just * ignore the reply to it later. Removing a msgb from the wqueue here would just introduce more * bug surface in terms of failing to update wqueue API's counters or some such. */ } static mgcp_trans_id_t mgcp_client_next_trans_id(struct mgcp_client *mgcp) { /* avoid zero trans_id to distinguish from unset trans_id */ if (!mgcp->next_trans_id) mgcp->next_trans_id ++; return mgcp->next_trans_id ++; } #define MGCP_CRCX_MANDATORY (MGCP_MSG_PRESENCE_ENDPOINT | \ MGCP_MSG_PRESENCE_CALL_ID | \ MGCP_MSG_PRESENCE_CONN_MODE) #define MGCP_MDCX_MANDATORY (MGCP_MSG_PRESENCE_ENDPOINT | \ MGCP_MSG_PRESENCE_CALL_ID | \ MGCP_MSG_PRESENCE_CONN_ID) #define MGCP_DLCX_MANDATORY (MGCP_MSG_PRESENCE_ENDPOINT) #define MGCP_AUEP_MANDATORY (MGCP_MSG_PRESENCE_ENDPOINT) #define MGCP_RSIP_MANDATORY 0 /* none */ /* Helper function for mgcp_msg_gen(): Add LCO information to MGCP message */ static int add_lco(struct msgb *msg, struct mgcp_msg *mgcp_msg) { unsigned int i; const char *codec; #define MSGB_PRINTF_OR_RET(FMT, ARGS...) do { \ if (msgb_printf(msg, FMT, ##ARGS) != 0) { \ LOGP(DLMGCP, LOGL_ERROR, "Message buffer too small, can not generate MGCP/SDP message\n"); \ return -ENOBUFS; \ } \ } while (0) MSGB_PRINTF_OR_RET("L:"); if (mgcp_msg->ptime) MSGB_PRINTF_OR_RET(" p:%u,", mgcp_msg->ptime); if (mgcp_msg->ptmap_len) { MSGB_PRINTF_OR_RET(" a:"); for (i = 0; i < mgcp_msg->ptmap_len; i++) { codec = get_value_string_or_null(osmo_mgcpc_codec_names, mgcp_msg->ptmap[i].codec); /* Note: Use codec descriptors from enum mgcp_codecs * in mgcp_client only! */ if (!codec) return -EINVAL; MSGB_PRINTF_OR_RET("%s", extract_codec_name(codec)); if (i < mgcp_msg->ptmap_len - 1) MSGB_PRINTF_OR_RET(";"); } MSGB_PRINTF_OR_RET(","); } MSGB_PRINTF_OR_RET(" nt:IN\r\n"); return 0; #undef MSGB_PRINTF_OR_RET } /* Helper function to obtain local IP address used in MGCP towards MGW, * in string format, to fill the SDP "Origin" ("o=") field. * return 0 on success, negative on error. */ static int get_mgcp_local_addr(const struct mgcp_client *mgcp, char *local_ip, size_t local_ip_len) { int fd; /* Try to get the socket local IP address if available: */ if (mgcp->iofd && ((fd = osmo_iofd_get_fd(mgcp->iofd)) >= 0)) { if (osmo_sock_get_local_ip(fd, local_ip, local_ip_len) == 0) return 0; /* else: continue below */ } /* If MGCP local address was explicitly specified in config, use it: */ if (mgcp->actual.local_addr) { osmo_strlcpy(local_ip, mgcp->actual.local_addr, local_ip_len); return 0; } /* Guess our local address based on system routing towards MGW: */ OSMO_ASSERT(local_ip_len >= INET6_ADDRSTRLEN); if (osmo_sock_local_ip(local_ip, mgcp->actual.remote_addr) == 0) return 0; LOGPMGW(mgcp, LOGL_ERROR, "Could not determine local IP-Address!\n"); return -EINVAL; } /* Helper function for mgcp_msg_gen(): Add SDP information to MGCP message */ static int add_sdp(struct msgb *msg, struct mgcp_msg *mgcp_msg, struct mgcp_client *mgcp) { unsigned int i; char local_ip[INET6_ADDRSTRLEN]; int local_ip_family, audio_ip_family; const char *codec; unsigned int pt; uint16_t audio_port; int rc; #define MSGB_PRINTF_OR_RET(FMT, ARGS...) do { \ if (msgb_printf(msg, FMT, ##ARGS) != 0) { \ LOGPMGW(mgcp, LOGL_ERROR, "Message buffer too small, can not generate MGCP message (SDP)\n"); \ return -ENOBUFS; \ } \ } while (0) /* Add separator to mark the beginning of the SDP block */ MSGB_PRINTF_OR_RET("\r\n"); /* Add SDP protocol version */ MSGB_PRINTF_OR_RET("v=0\r\n"); /* Determine local IP-Address */ rc = get_mgcp_local_addr(mgcp, local_ip, sizeof(local_ip)); if (rc < 0) return rc; local_ip_family = osmo_ip_str_type(local_ip); if (local_ip_family == AF_UNSPEC) return -EINVAL; /* Add owner/creator (SDP) */ MSGB_PRINTF_OR_RET("o=- %x 23 IN IP%c %s\r\n", mgcp_msg->call_id, local_ip_family == AF_INET6 ? '6' : '4', local_ip); /* Add session name (none) */ MSGB_PRINTF_OR_RET("s=-\r\n"); /* Add RTP address */ if (mgcp_msg->presence & MGCP_MSG_PRESENCE_AUDIO_IP) { audio_ip_family = osmo_ip_str_type(mgcp_msg->audio_ip); if (audio_ip_family == AF_UNSPEC) return -EINVAL; if (strlen(mgcp_msg->audio_ip) <= 0) { LOGPMGW(mgcp, LOGL_ERROR, "Empty ip address, can not generate MGCP message\n"); return -EINVAL; } MSGB_PRINTF_OR_RET("c=IN IP%c %s\r\n", audio_ip_family == AF_INET6 ? '6' : '4', mgcp_msg->audio_ip); } /* Add time description, active time (SDP) */ MSGB_PRINTF_OR_RET("t=0 0\r\n"); /* Add RTP address port and codecs */ audio_port = 0; if ((mgcp_msg->presence & MGCP_MSG_PRESENCE_AUDIO_PORT)) { audio_port = mgcp_msg->audio_port; if (!audio_port) { LOGPMGW(mgcp, LOGL_ERROR, "Invalid port number, can not generate MGCP message\n"); return -EINVAL; } } MSGB_PRINTF_OR_RET("m=audio %u RTP/AVP", audio_port); for (i = 0; i < mgcp_msg->ptmap_len; i++) MSGB_PRINTF_OR_RET(" %u", mgcp_msg->ptmap[i].pt); MSGB_PRINTF_OR_RET("\r\n"); /* Add optional codec parameters (fmtp) */ for (i = 0; i < mgcp_msg->ptmap_len; i++) { pt = mgcp_msg->ptmap[i].pt; /* Add fmtp string, if any is set. */ if (mgcp_msg->ptmap[i].fmtp[0]) { MSGB_PRINTF_OR_RET("a=fmtp:%u %s\r\n", pt, mgcp_msg->ptmap[i].fmtp); continue; } /* LEGACY COMPAT. Fill in fmtp with the legacy mgcp_msg->param, * if any, when no individual fmtp is set on the codec. */ if (!mgcp_msg->param_present) continue; switch (mgcp_msg->ptmap[i].codec) { case CODEC_AMR_8000_1: case CODEC_AMRWB_16000_1: if (!mgcp_msg->param.amr_octet_aligned_present) break; MSGB_PRINTF_OR_RET("a=fmtp:%u octet-align=%d\r\n", pt, (int)mgcp_msg->param.amr_octet_aligned); break; case CODEC_GSM_8000_1: case CODEC_GSMEFR_8000_1: if (!mgcp_msg->param.fr_efr_twts001_present) break; MSGB_PRINTF_OR_RET("a=fmtp:%u tw-ts-001=%d\r\n", pt, (int)mgcp_msg->param.fr_efr_twts001); break; case CODEC_GSMHR_8000_1: if (!mgcp_msg->param.hr_twts002_present) break; MSGB_PRINTF_OR_RET("a=fmtp:%u tw-ts-002=%d\r\n", pt, (int)mgcp_msg->param.hr_twts002); break; default: /* no parameters for the remaining codecs */ break; } } for (i = 0; i < mgcp_msg->ptmap_len; i++) { pt = mgcp_msg->ptmap[i].pt; /* Note: Only dynamic payload type from the range 96-127 * require to be explained further via rtpmap. All others * are implcitly definedby the number in m=audio */ if (pt >= 96 && pt <= 127) { codec = get_value_string_or_null(osmo_mgcpc_codec_names, mgcp_msg->ptmap[i].codec); /* Note: Use codec descriptors from enum mgcp_codecs * in mgcp_client only! */ if (!codec) return -EINVAL; MSGB_PRINTF_OR_RET("a=rtpmap:%u %s\r\n", pt, codec); } } if (mgcp_msg->ptime) MSGB_PRINTF_OR_RET("a=ptime:%u\r\n", mgcp_msg->ptime); return 0; #undef MSGB_PRINTF_OR_RET } /*! Generate an MGCP message * \param[in] mgcp MGCP client descriptor. * \param[in] mgcp_msg Message description * \returns message buffer on success, NULL on error. */ struct msgb *mgcp_msg_gen(struct mgcp_client *mgcp, struct mgcp_msg *mgcp_msg) { mgcp_trans_id_t trans_id = mgcp_client_next_trans_id(mgcp); uint32_t mandatory_mask; struct msgb *msg = msgb_alloc_headroom(4096, 128, "MGCP tx"); bool use_sdp = false; char buf[32]; #define MSGB_PRINTF_OR_RET(FMT, ARGS...) do { \ if (msgb_printf(msg, FMT, ##ARGS) != 0) { \ LOGPMGW(mgcp, LOGL_ERROR, "Message buffer too small, can not generate MGCP/SDP message\n"); \ goto exit_error; \ } \ } while (0) msg->l2h = msg->data; msg->cb[MSGB_CB_MGCP_TRANS_ID] = trans_id; /* Add command verb */ switch (mgcp_msg->verb) { case MGCP_VERB_CRCX: mandatory_mask = MGCP_CRCX_MANDATORY; MSGB_PRINTF_OR_RET("CRCX %u", trans_id); break; case MGCP_VERB_MDCX: mandatory_mask = MGCP_MDCX_MANDATORY; MSGB_PRINTF_OR_RET("MDCX %u", trans_id); break; case MGCP_VERB_DLCX: mandatory_mask = MGCP_DLCX_MANDATORY; MSGB_PRINTF_OR_RET("DLCX %u", trans_id); break; case MGCP_VERB_AUEP: mandatory_mask = MGCP_AUEP_MANDATORY; MSGB_PRINTF_OR_RET("AUEP %u", trans_id); break; case MGCP_VERB_RSIP: mandatory_mask = MGCP_RSIP_MANDATORY; MSGB_PRINTF_OR_RET("RSIP %u", trans_id); break; default: LOGPMGW(mgcp, LOGL_ERROR, "Invalid command verb, can not generate MGCP message\n"); goto exit_error; } /* Check if mandatory fields are missing */ if (!((mgcp_msg->presence & mandatory_mask) == mandatory_mask)) { LOGPMGW(mgcp, LOGL_ERROR, "One or more missing mandatory fields, can not generate MGCP message\n"); goto exit_error; } /* Add endpoint name */ if (mgcp_msg->presence & MGCP_MSG_PRESENCE_ENDPOINT) { if (strlen(mgcp_msg->endpoint) <= 0) { LOGPMGW(mgcp, LOGL_ERROR, "Empty endpoint name, can not generate MGCP message\n"); goto exit_error; } if (strstr(mgcp_msg->endpoint, "@") == NULL) { LOGPMGW(mgcp, LOGL_ERROR, "Endpoint name (%s) lacks separator (@), can not generate MGCP message\n", mgcp_msg->endpoint); goto exit_error; } MSGB_PRINTF_OR_RET(" %s", mgcp_msg->endpoint); } /* Add protocol version */ MSGB_PRINTF_OR_RET(" MGCP 1.0\r\n"); /* Add call id */ if (mgcp_msg->presence & MGCP_MSG_PRESENCE_CALL_ID) MSGB_PRINTF_OR_RET("C: %x\r\n", mgcp_msg->call_id); /* Add connection id */ if (mgcp_msg->presence & MGCP_MSG_PRESENCE_CONN_ID) { if (strlen(mgcp_msg->conn_id) <= 0) { LOGPMGW(mgcp, LOGL_ERROR, "Empty connection id, can not generate MGCP message\n"); goto exit_error; } MSGB_PRINTF_OR_RET("I: %s\r\n", mgcp_msg->conn_id); } /* Using SDP makes sense when a valid IP or Port is specified, * if we do not know this information yet, we fall back to LCO */ if (mgcp_msg->presence & MGCP_MSG_PRESENCE_AUDIO_IP || mgcp_msg->presence & MGCP_MSG_PRESENCE_AUDIO_PORT) use_sdp = true; /* Add local connection options (LCO) */ if (!use_sdp && (mgcp_msg->verb == MGCP_VERB_CRCX || mgcp_msg->verb == MGCP_VERB_MDCX)) { if (add_lco(msg, mgcp_msg) < 0) { LOGPMGW(mgcp, LOGL_ERROR, "Failed to add LCO, can not generate MGCP message\n"); goto exit_error; } } /* Add mode */ if (mgcp_msg->presence & MGCP_MSG_PRESENCE_CONN_MODE) MSGB_PRINTF_OR_RET("M: %s\r\n", mgcp_client_cmode_name(mgcp_msg->conn_mode)); /* Add X-Osmo-IGN */ if ((mgcp_msg->presence & MGCP_MSG_PRESENCE_X_OSMO_IGN) && (mgcp_msg->x_osmo_ign != 0)) MSGB_PRINTF_OR_RET(MGCP_X_OSMO_IGN_HEADER "%s\r\n", mgcp_msg->x_osmo_ign & MGCP_X_OSMO_IGN_CALLID ? " C" : ""); /* Add X-Osmo-Osmux */ if ((mgcp_msg->presence & MGCP_MSG_PRESENCE_X_OSMO_OSMUX_CID)) { if (mgcp_msg->x_osmo_osmux_cid < -1 || mgcp_msg->x_osmo_osmux_cid > OSMUX_CID_MAX) { LOGPMGW(mgcp, LOGL_ERROR, "Wrong Osmux CID %d, can not generate MGCP message\n", mgcp_msg->x_osmo_osmux_cid); goto exit_error; } snprintf(buf, sizeof(buf), " %d", mgcp_msg->x_osmo_osmux_cid); MSGB_PRINTF_OR_RET(MGCP_X_OSMO_OSMUX_HEADER "%s\r\n", mgcp_msg->x_osmo_osmux_cid == -1 ? " *" : buf); } /* Add session description protocol (SDP) */ if (use_sdp && (mgcp_msg->verb == MGCP_VERB_CRCX || mgcp_msg->verb == MGCP_VERB_MDCX)) { if (add_sdp(msg, mgcp_msg, mgcp) < 0) { LOGPMGW(mgcp, LOGL_ERROR, "Failed to add SDP, can not generate MGCP message\n"); goto exit_error; } } return msg; exit_error: msgb_free(msg); return NULL; #undef MSGB_PRINTF_OR_RET } /*! Retrieve the MGCP transaction ID from a msgb generated by mgcp_msg_gen() * \param[in] msg message buffer * \returns Transaction id. */ mgcp_trans_id_t mgcp_msg_trans_id(struct msgb *msg) { return (mgcp_trans_id_t)msg->cb[MSGB_CB_MGCP_TRANS_ID]; } /*! Get the configuration parameters for a given MGCP client instance * \param[in] mgcp MGCP client descriptor. * \returns configuration */ struct mgcp_client_conf *mgcp_client_conf_actual(struct mgcp_client *mgcp) { return &mgcp->actual; } const struct value_string mgcp_client_connection_mode_strs[] = { { MGCP_CONN_NONE, "none" }, { MGCP_CONN_RECV_SEND, "sendrecv" }, { MGCP_CONN_SEND_ONLY, "sendonly" }, { MGCP_CONN_RECV_ONLY, "recvonly" }, { MGCP_CONN_CONFECHO, "confecho" }, { MGCP_CONN_LOOPBACK, "loopback" }, { 0, NULL } }; /*! Get MGCP client instance name (VTY). * \param[in] mgcp MGCP client descriptor. * \returns MGCP client name. * * The user can only modify the name of an MGCP client instance when it is * part of a pool. For single MGCP client instances and MGCP client instance * where no description is set via the VTY, the MGW domain name will be used * as name. */ const char *mgcp_client_name(const struct mgcp_client *mgcp) { if (!mgcp) return "(null)"; if (mgcp->actual.description) return mgcp->actual.description; else return mgcp_client_endpoint_domain(mgcp); } /*! Return typical cmp result, comparing a to b. * Return 0 if a == b, -1 if a < b, 1 if a > b; comparing all members of ptmap in turn. */ int ptmap_cmp(const struct ptmap *a, const struct ptmap *b) { int rc; if (a == b) return 0; if (!a) return -1; if (!b) return 1; rc = OSMO_CMP(a->codec, b->codec); if (rc) return rc; rc = OSMO_CMP(a->pt, b->pt); if (rc) return rc; return strcmp(a->fmtp, b->fmtp); }