| /* A Media Gateway Control Protocol Media Gateway: RFC 3435 */ |
| /* The protocol implementation */ |
| |
| /* |
| * (C) 2009-2010 by Holger Hans Peter Freyther <zecke@selfish.org> |
| * (C) 2009-2010 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 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, write to the Free Software Foundation, Inc., |
| * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| */ |
| |
| #include <ctype.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <time.h> |
| #include <limits.h> |
| #include <unistd.h> |
| |
| #include <openbsc/debug.h> |
| #include <osmocore/msgb.h> |
| #include <osmocore/talloc.h> |
| #include <openbsc/gsm_data.h> |
| #include <osmocore/select.h> |
| #include <openbsc/mgcp.h> |
| #include <openbsc/mgcp_internal.h> |
| |
| /** |
| * Macro for tokenizing MGCP messages and SDP in one go. |
| * |
| */ |
| #define MSG_TOKENIZE_START \ |
| line_start = 0; \ |
| for (i = 0; i < msgb_l3len(msg); ++i) { \ |
| /* we have a line end */ \ |
| if (msg->l3h[i] == '\n') { \ |
| /* skip the first line */ \ |
| if (line_start == 0) { \ |
| line_start = i + 1; \ |
| continue; \ |
| } \ |
| \ |
| /* check if we have a proper param */ \ |
| if (i - line_start == 1 && msg->l3h[line_start] == '\r') { \ |
| } else if (i - line_start > 2 \ |
| && islower(msg->l3h[line_start]) \ |
| && msg->l3h[line_start + 1] == '=') { \ |
| } else if (i - line_start < 3 \ |
| || msg->l3h[line_start + 1] != ':' \ |
| || msg->l3h[line_start + 2] != ' ') \ |
| goto error; \ |
| \ |
| msg->l3h[i] = '\0'; \ |
| if (msg->l3h[i-1] == '\r') \ |
| msg->l3h[i-1] = '\0'; |
| |
| #define MSG_TOKENIZE_END \ |
| line_start = i + 1; \ |
| } \ |
| } |
| |
| static void mgcp_rtp_end_reset(struct mgcp_rtp_end *end); |
| |
| struct mgcp_request { |
| char *name; |
| struct msgb *(*handle_request) (struct mgcp_config *cfg, struct msgb *msg); |
| char *debug_name; |
| }; |
| |
| #define MGCP_REQUEST(NAME, REQ, DEBUG_NAME) \ |
| { .name = NAME, .handle_request = REQ, .debug_name = DEBUG_NAME }, |
| |
| static struct msgb *handle_audit_endpoint(struct mgcp_config *cfg, struct msgb *msg); |
| static struct msgb *handle_create_con(struct mgcp_config *cfg, struct msgb *msg); |
| static struct msgb *handle_delete_con(struct mgcp_config *cfg, struct msgb *msg); |
| static struct msgb *handle_modify_con(struct mgcp_config *cfg, struct msgb *msg); |
| static struct msgb *handle_rsip(struct mgcp_config *cfg, struct msgb *msg); |
| |
| static void create_transcoder(struct mgcp_endpoint *endp); |
| static void delete_transcoder(struct mgcp_endpoint *endp); |
| |
| static uint32_t generate_call_id(struct mgcp_config *cfg) |
| { |
| int i; |
| |
| /* use the call id */ |
| ++cfg->last_call_id; |
| |
| /* handle wrap around */ |
| if (cfg->last_call_id == CI_UNUSED) |
| ++cfg->last_call_id; |
| |
| /* callstack can only be of size number_of_endpoints */ |
| /* verify that the call id is free, e.g. in case of overrun */ |
| for (i = 1; i < cfg->number_endpoints; ++i) |
| if (cfg->endpoints[i].ci == cfg->last_call_id) |
| return generate_call_id(cfg); |
| |
| return cfg->last_call_id; |
| } |
| |
| /* |
| * array of function pointers for handling various |
| * messages. In the future this might be binary sorted |
| * for performance reasons. |
| */ |
| static const struct mgcp_request mgcp_requests [] = { |
| MGCP_REQUEST("AUEP", handle_audit_endpoint, "AuditEndpoint") |
| MGCP_REQUEST("CRCX", handle_create_con, "CreateConnection") |
| MGCP_REQUEST("DLCX", handle_delete_con, "DeleteConnection") |
| MGCP_REQUEST("MDCX", handle_modify_con, "ModifiyConnection") |
| |
| /* SPEC extension */ |
| MGCP_REQUEST("RSIP", handle_rsip, "ReSetInProgress") |
| }; |
| |
| static struct msgb *mgcp_msgb_alloc(void) |
| { |
| struct msgb *msg; |
| msg = msgb_alloc_headroom(4096, 128, "MGCP msg"); |
| if (!msg) |
| LOGP(DMGCP, LOGL_ERROR, "Failed to msgb for MGCP data.\n"); |
| |
| return msg; |
| } |
| |
| struct msgb *mgcp_create_response_with_data(int code, const char *msg, const char *trans, |
| const char *data) |
| { |
| int len; |
| struct msgb *res; |
| |
| res = mgcp_msgb_alloc(); |
| if (!res) |
| return NULL; |
| |
| if (data) { |
| len = snprintf((char *) res->data, 2048, "%d %s\n%s", code, trans, data); |
| } else { |
| len = snprintf((char *) res->data, 2048, "%d %s\n", code, trans); |
| } |
| |
| res->l2h = msgb_put(res, len); |
| LOGP(DMGCP, LOGL_DEBUG, "Sending response: code: %d for '%s'\n", code, res->l2h); |
| return res; |
| } |
| |
| static struct msgb *create_response(int code, const char *msg, const char *trans) |
| { |
| return mgcp_create_response_with_data(code, msg, trans, NULL); |
| } |
| |
| static struct msgb *create_response_with_sdp(struct mgcp_endpoint *endp, |
| const char *msg, const char *trans_id) |
| { |
| const char *addr = endp->cfg->local_ip; |
| char sdp_record[4096]; |
| |
| if (!addr) |
| addr = endp->cfg->source_addr; |
| |
| snprintf(sdp_record, sizeof(sdp_record) - 1, |
| "I: %u\n\n" |
| "v=0\r\n" |
| "c=IN IP4 %s\r\n" |
| "m=audio %d RTP/AVP %d\r\n" |
| "a=rtpmap:%d %s\r\n", |
| endp->ci, addr, endp->net_end.local_port, |
| endp->bts_end.payload_type, endp->bts_end.payload_type, |
| endp->cfg->audio_name); |
| return mgcp_create_response_with_data(200, msg, trans_id, sdp_record); |
| } |
| |
| /* |
| * 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) |
| { |
| int code; |
| struct msgb *resp = NULL; |
| |
| if (msgb_l2len(msg) < 4) { |
| LOGP(DMGCP, LOGL_ERROR, "mgs too short: %d\n", msg->len); |
| return NULL; |
| } |
| |
| /* attempt to treat it as a response */ |
| if (sscanf((const char *)&msg->l2h[0], "%3d %*s", &code) == 1) { |
| LOGP(DMGCP, LOGL_DEBUG, "Response: Code: %d\n", code); |
| } else { |
| int i, handled = 0; |
| msg->l3h = &msg->l2h[4]; |
| for (i = 0; i < ARRAY_SIZE(mgcp_requests); ++i) |
| if (strncmp(mgcp_requests[i].name, (const char *) &msg->l2h[0], 4) == 0) { |
| handled = 1; |
| resp = mgcp_requests[i].handle_request(cfg, msg); |
| break; |
| } |
| if (!handled) { |
| LOGP(DMGCP, LOGL_NOTICE, "MSG with type: '%.4s' not handled\n", &msg->l2h[0]); |
| } |
| } |
| |
| return resp; |
| } |
| |
| /* string tokenizer for the poor */ |
| static int find_msg_pointers(struct msgb *msg, struct mgcp_msg_ptr *ptrs, int ptrs_length) |
| { |
| int i, found = 0; |
| |
| int whitespace = 1; |
| for (i = 0; i < msgb_l3len(msg) && ptrs_length > 0; ++i) { |
| /* if we have a space we found an end */ |
| if (msg->l3h[i] == ' ' || msg->l3h[i] == '\r' || msg->l3h[i] == '\n') { |
| if (!whitespace) { |
| ++found; |
| whitespace = 1; |
| ptrs->length = i - ptrs->start - 1; |
| ++ptrs; |
| --ptrs_length; |
| } else { |
| /* skip any number of whitespace */ |
| } |
| |
| /* line end... stop */ |
| if (msg->l3h[i] == '\r' || msg->l3h[i] == '\n') |
| break; |
| } else if (msg->l3h[i] == '\r' || msg->l3h[i] == '\n') { |
| /* line end, be done */ |
| break; |
| } else if (whitespace) { |
| whitespace = 0; |
| ptrs->start = i; |
| } |
| } |
| |
| if (ptrs_length == 0) |
| return -1; |
| return found; |
| } |
| |
| static struct mgcp_endpoint *find_endpoint(struct mgcp_config *cfg, const char *mgcp) |
| { |
| char *endptr = NULL; |
| unsigned int gw = INT_MAX; |
| |
| gw = strtoul(mgcp, &endptr, 16); |
| if (gw == 0 || gw >= cfg->number_endpoints || strcmp(endptr, "@mgw") != 0) { |
| LOGP(DMGCP, LOGL_ERROR, "Not able to find endpoint: '%s'\n", mgcp); |
| return NULL; |
| } |
| |
| return &cfg->endpoints[gw]; |
| } |
| |
| int mgcp_analyze_header(struct mgcp_config *cfg, struct msgb *msg, |
| struct mgcp_msg_ptr *ptr, int size, |
| const char **transaction_id, struct mgcp_endpoint **endp) |
| { |
| int found; |
| |
| *transaction_id = "000000"; |
| |
| if (size < 3) { |
| LOGP(DMGCP, LOGL_ERROR, "Not enough space in ptr\n"); |
| return -1; |
| } |
| |
| found = find_msg_pointers(msg, ptr, size); |
| |
| if (found <= 3) { |
| LOGP(DMGCP, LOGL_ERROR, "Gateway: Not enough params. Found: %d\n", found); |
| return -1; |
| } |
| |
| /* |
| * replace the space with \0. the main method gurantess that |
| * we still have + 1 for null termination |
| */ |
| msg->l3h[ptr[3].start + ptr[3].length + 1] = '\0'; |
| msg->l3h[ptr[2].start + ptr[2].length + 1] = '\0'; |
| msg->l3h[ptr[1].start + ptr[1].length + 1] = '\0'; |
| msg->l3h[ptr[0].start + ptr[0].length + 1] = '\0'; |
| |
| if (strncmp("1.0", (const char *)&msg->l3h[ptr[3].start], 3) != 0 |
| || strncmp("MGCP", (const char *)&msg->l3h[ptr[2].start], 4) != 0) { |
| LOGP(DMGCP, LOGL_ERROR, "Wrong MGCP version. Not handling: '%s' '%s'\n", |
| (const char *)&msg->l3h[ptr[3].start], |
| (const char *)&msg->l3h[ptr[2].start]); |
| return -1; |
| } |
| |
| *transaction_id = (const char *)&msg->l3h[ptr[0].start]; |
| if (endp) { |
| *endp = find_endpoint(cfg, (const char *)&msg->l3h[ptr[1].start]); |
| return *endp == NULL; |
| } |
| return 0; |
| } |
| |
| static int verify_call_id(const struct mgcp_endpoint *endp, |
| const char *callid) |
| { |
| if (strcmp(endp->callid, callid) != 0) { |
| LOGP(DMGCP, LOGL_ERROR, "CallIDs does not match on 0x%x. '%s' != '%s'\n", |
| ENDPOINT_NUMBER(endp), endp->callid, callid); |
| return -1; |
| } |
| |
| return 0; |
| } |
| |
| static int verify_ci(const struct mgcp_endpoint *endp, |
| const char *_ci) |
| { |
| uint32_t ci = strtoul(_ci, NULL, 10); |
| |
| if (ci != endp->ci) { |
| LOGP(DMGCP, LOGL_ERROR, "ConnectionIdentifiers do not match on 0x%x. %u != %s\n", |
| ENDPOINT_NUMBER(endp), endp->ci, _ci); |
| return -1; |
| } |
| |
| return 0; |
| } |
| |
| static struct msgb *handle_audit_endpoint(struct mgcp_config *cfg, struct msgb *msg) |
| { |
| struct mgcp_msg_ptr data_ptrs[6]; |
| int found, response; |
| const char *trans_id; |
| struct mgcp_endpoint *endp; |
| |
| found = mgcp_analyze_header(cfg, msg, data_ptrs, ARRAY_SIZE(data_ptrs), &trans_id, &endp); |
| if (found != 0) |
| response = 500; |
| else |
| response = 200; |
| |
| return create_response(response, "AUEP", trans_id); |
| } |
| |
| static int parse_conn_mode(const char *msg, int *conn_mode) |
| { |
| int ret = 0; |
| if (strcmp(msg, "recvonly") == 0) |
| *conn_mode = MGCP_CONN_RECV_ONLY; |
| else if (strcmp(msg, "sendrecv") == 0) |
| *conn_mode = MGCP_CONN_RECV_SEND; |
| else if (strcmp(msg, "sendonly") == 0) |
| *conn_mode = MGCP_CONN_SEND_ONLY; |
| else if (strcmp(msg, "loopback") == 0) |
| *conn_mode = MGCP_CONN_LOOPBACK; |
| else { |
| LOGP(DMGCP, LOGL_ERROR, "Unknown connection mode: '%s'\n", msg); |
| ret = -1; |
| } |
| |
| return ret; |
| } |
| |
| static int allocate_port(struct mgcp_endpoint *endp, struct mgcp_rtp_end *end, |
| struct mgcp_port_range *range, |
| int (*alloc)(struct mgcp_endpoint *endp, int port)) |
| { |
| int i; |
| |
| if (range->mode == PORT_ALLOC_STATIC) { |
| end->local_alloc = PORT_ALLOC_STATIC; |
| return 0; |
| } |
| |
| /* attempt to find a port */ |
| for (i = 0; i < 200; ++i) { |
| int rc; |
| |
| if (range->last_port >= range->range_end) |
| range->last_port = range->range_start; |
| |
| rc = alloc(endp, range->last_port); |
| |
| range->last_port += 2; |
| if (rc == 0) { |
| end->local_alloc = PORT_ALLOC_DYNAMIC; |
| return 0; |
| } |
| |
| } |
| |
| LOGP(DMGCP, LOGL_ERROR, "Allocating a RTP/RTCP port failed 200 times 0x%x.\n", |
| ENDPOINT_NUMBER(endp)); |
| return -1; |
| } |
| |
| static int allocate_ports(struct mgcp_endpoint *endp) |
| { |
| if (allocate_port(endp, &endp->net_end, &endp->cfg->net_ports, |
| mgcp_bind_net_rtp_port) != 0) |
| return -1; |
| |
| if (allocate_port(endp, &endp->bts_end, &endp->cfg->bts_ports, |
| mgcp_bind_bts_rtp_port) != 0) { |
| mgcp_rtp_end_reset(&endp->net_end); |
| return -1; |
| } |
| |
| if (endp->cfg->transcoder_ip) { |
| if (allocate_port(endp, &endp->trans_net, |
| &endp->cfg->transcoder_ports, |
| mgcp_bind_trans_net_rtp_port) != 0) { |
| mgcp_rtp_end_reset(&endp->net_end); |
| mgcp_rtp_end_reset(&endp->bts_end); |
| return -1; |
| } |
| |
| if (allocate_port(endp, &endp->trans_bts, |
| &endp->cfg->transcoder_ports, |
| mgcp_bind_trans_bts_rtp_port) != 0) { |
| mgcp_rtp_end_reset(&endp->net_end); |
| mgcp_rtp_end_reset(&endp->bts_end); |
| mgcp_rtp_end_reset(&endp->trans_net); |
| return -1; |
| } |
| |
| /* remember that we have set up transcoding */ |
| endp->is_transcoded = 1; |
| } |
| |
| return 0; |
| } |
| |
| static struct msgb *handle_create_con(struct mgcp_config *cfg, struct msgb *msg) |
| { |
| struct mgcp_msg_ptr data_ptrs[6]; |
| int found, i, line_start; |
| const char *trans_id; |
| struct mgcp_endpoint *endp; |
| int error_code = 400; |
| |
| found = mgcp_analyze_header(cfg, msg, data_ptrs, ARRAY_SIZE(data_ptrs), &trans_id, &endp); |
| if (found != 0) |
| return create_response(510, "CRCX", trans_id); |
| |
| if (endp->allocated) { |
| if (cfg->force_realloc) { |
| LOGP(DMGCP, LOGL_NOTICE, "Endpoint 0x%x already allocated. Forcing realloc.\n", |
| ENDPOINT_NUMBER(endp)); |
| mgcp_free_endp(endp); |
| if (cfg->realloc_cb) |
| cfg->realloc_cb(cfg, ENDPOINT_NUMBER(endp)); |
| } else { |
| LOGP(DMGCP, LOGL_ERROR, "Endpoint is already used. 0x%x\n", |
| ENDPOINT_NUMBER(endp)); |
| return create_response(400, "CRCX", trans_id); |
| } |
| } |
| |
| /* parse CallID C: and LocalParameters L: */ |
| MSG_TOKENIZE_START |
| switch (msg->l3h[line_start]) { |
| case 'L': |
| endp->local_options = talloc_strdup(cfg->endpoints, |
| (const char *)&msg->l3h[line_start + 3]); |
| break; |
| case 'C': |
| endp->callid = talloc_strdup(cfg->endpoints, |
| (const char *)&msg->l3h[line_start + 3]); |
| break; |
| case 'M': |
| if (parse_conn_mode((const char *)&msg->l3h[line_start + 3], |
| &endp->conn_mode) != 0) { |
| error_code = 517; |
| goto error2; |
| } |
| |
| endp->orig_mode = endp->conn_mode; |
| break; |
| default: |
| LOGP(DMGCP, LOGL_NOTICE, "Unhandled option: '%c'/%d on 0x%x\n", |
| msg->l3h[line_start], msg->l3h[line_start], |
| ENDPOINT_NUMBER(endp)); |
| break; |
| } |
| MSG_TOKENIZE_END |
| |
| /* initialize */ |
| endp->net_end.rtp_port = endp->net_end.rtcp_port = endp->bts_end.rtp_port = endp->bts_end.rtcp_port = 0; |
| |
| /* set to zero until we get the info */ |
| memset(&endp->net_end.addr, 0, sizeof(endp->net_end.addr)); |
| |
| /* bind to the port now */ |
| if (allocate_ports(endp) != 0) |
| goto error2; |
| |
| /* assign a local call identifier or fail */ |
| endp->ci = generate_call_id(cfg); |
| if (endp->ci == CI_UNUSED) |
| goto error2; |
| |
| endp->allocated = 1; |
| endp->bts_end.payload_type = cfg->audio_payload; |
| |
| /* policy CB */ |
| if (cfg->policy_cb) { |
| switch (cfg->policy_cb(cfg, ENDPOINT_NUMBER(endp), MGCP_ENDP_CRCX, trans_id)) { |
| case MGCP_POLICY_REJECT: |
| LOGP(DMGCP, LOGL_NOTICE, "CRCX rejected by policy on 0x%x\n", |
| ENDPOINT_NUMBER(endp)); |
| mgcp_free_endp(endp); |
| return create_response(400, "CRCX", trans_id); |
| break; |
| case MGCP_POLICY_DEFER: |
| /* stop processing */ |
| create_transcoder(endp); |
| return NULL; |
| break; |
| case MGCP_POLICY_CONT: |
| /* just continue */ |
| break; |
| } |
| } |
| |
| LOGP(DMGCP, LOGL_DEBUG, "Creating endpoint on: 0x%x CI: %u port: %u/%u\n", |
| ENDPOINT_NUMBER(endp), endp->ci, |
| endp->net_end.local_port, endp->bts_end.local_port); |
| if (cfg->change_cb) |
| cfg->change_cb(cfg, ENDPOINT_NUMBER(endp), MGCP_ENDP_CRCX); |
| |
| create_transcoder(endp); |
| return create_response_with_sdp(endp, "CRCX", trans_id); |
| error: |
| LOGP(DMGCP, LOGL_ERROR, "Malformed line: %s on 0x%x with: line_start: %d %d\n", |
| hexdump(msg->l3h, msgb_l3len(msg)), |
| ENDPOINT_NUMBER(endp), line_start, i); |
| return create_response(error_code, "CRCX", trans_id); |
| |
| error2: |
| mgcp_free_endp(endp); |
| LOGP(DMGCP, LOGL_NOTICE, "Resource error on 0x%x\n", ENDPOINT_NUMBER(endp)); |
| return create_response(error_code, "CRCX", trans_id); |
| } |
| |
| static struct msgb *handle_modify_con(struct mgcp_config *cfg, struct msgb *msg) |
| { |
| struct mgcp_msg_ptr data_ptrs[6]; |
| int found, i, line_start; |
| const char *trans_id; |
| struct mgcp_endpoint *endp; |
| int error_code = 500; |
| int silent = 0; |
| |
| found = mgcp_analyze_header(cfg, msg, data_ptrs, ARRAY_SIZE(data_ptrs), &trans_id, &endp); |
| if (found != 0) |
| return create_response(510, "MDCX", trans_id); |
| |
| if (endp->ci == CI_UNUSED) { |
| LOGP(DMGCP, LOGL_ERROR, "Endpoint is not holding a connection. 0x%x\n", ENDPOINT_NUMBER(endp)); |
| return create_response(400, "MDCX", trans_id); |
| } |
| |
| MSG_TOKENIZE_START |
| switch (msg->l3h[line_start]) { |
| case 'C': { |
| if (verify_call_id(endp, (const char *)&msg->l3h[line_start + 3]) != 0) |
| goto error3; |
| break; |
| } |
| case 'I': { |
| if (verify_ci(endp, (const char *)&msg->l3h[line_start + 3]) != 0) |
| goto error3; |
| break; |
| } |
| case 'L': |
| /* skip */ |
| break; |
| case 'M': |
| if (parse_conn_mode((const char *)&msg->l3h[line_start + 3], |
| &endp->conn_mode) != 0) { |
| error_code = 517; |
| goto error3; |
| } |
| endp->orig_mode = endp->conn_mode; |
| break; |
| case 'Z': |
| silent = strcmp("noanswer", (const char *)&msg->l3h[line_start + 3]) == 0; |
| break; |
| case '\0': |
| /* SDP file begins */ |
| break; |
| case 'a': |
| case 'o': |
| case 's': |
| case 't': |
| case 'v': |
| /* skip these SDP attributes */ |
| break; |
| case 'm': { |
| int port; |
| int payload; |
| const char *param = (const char *)&msg->l3h[line_start]; |
| |
| if (sscanf(param, "m=audio %d RTP/AVP %d", &port, &payload) == 2) { |
| endp->net_end.rtp_port = htons(port); |
| endp->net_end.rtcp_port = htons(port + 1); |
| endp->net_end.payload_type = payload; |
| } |
| break; |
| } |
| case 'c': { |
| char ipv4[16]; |
| const char *param = (const char *)&msg->l3h[line_start]; |
| |
| if (sscanf(param, "c=IN IP4 %15s", ipv4) == 1) { |
| inet_aton(ipv4, &endp->net_end.addr); |
| } |
| break; |
| } |
| default: |
| LOGP(DMGCP, LOGL_NOTICE, "Unhandled option: '%c'/%d on 0x%x\n", |
| msg->l3h[line_start], msg->l3h[line_start], |
| ENDPOINT_NUMBER(endp)); |
| break; |
| } |
| MSG_TOKENIZE_END |
| |
| /* policy CB */ |
| if (cfg->policy_cb) { |
| switch (cfg->policy_cb(cfg, ENDPOINT_NUMBER(endp), MGCP_ENDP_MDCX, trans_id)) { |
| case MGCP_POLICY_REJECT: |
| LOGP(DMGCP, LOGL_NOTICE, "MDCX rejected by policy on 0x%x\n", |
| ENDPOINT_NUMBER(endp)); |
| if (silent) |
| goto out_silent; |
| return create_response(400, "MDCX", trans_id); |
| break; |
| case MGCP_POLICY_DEFER: |
| /* stop processing */ |
| return NULL; |
| break; |
| case MGCP_POLICY_CONT: |
| /* just continue */ |
| break; |
| } |
| } |
| |
| /* modify */ |
| LOGP(DMGCP, LOGL_DEBUG, "Modified endpoint on: 0x%x Server: %s:%u\n", |
| ENDPOINT_NUMBER(endp), inet_ntoa(endp->net_end.addr), ntohs(endp->net_end.rtp_port)); |
| if (cfg->change_cb) |
| cfg->change_cb(cfg, ENDPOINT_NUMBER(endp), MGCP_ENDP_MDCX); |
| if (silent) |
| goto out_silent; |
| |
| return create_response_with_sdp(endp, "MDCX", trans_id); |
| |
| error: |
| LOGP(DMGCP, LOGL_ERROR, "Malformed line: %s on 0x%x with: line_start: %d %d %d\n", |
| hexdump(msg->l3h, msgb_l3len(msg)), |
| ENDPOINT_NUMBER(endp), line_start, i, msg->l3h[line_start]); |
| return create_response(error_code, "MDCX", trans_id); |
| |
| error3: |
| return create_response(error_code, "MDCX", trans_id); |
| |
| |
| out_silent: |
| return NULL; |
| } |
| |
| static struct msgb *handle_delete_con(struct mgcp_config *cfg, struct msgb *msg) |
| { |
| struct mgcp_msg_ptr data_ptrs[6]; |
| int found, i, line_start; |
| const char *trans_id; |
| struct mgcp_endpoint *endp; |
| int error_code = 400; |
| int silent = 0; |
| |
| found = mgcp_analyze_header(cfg, msg, data_ptrs, ARRAY_SIZE(data_ptrs), &trans_id, &endp); |
| if (found != 0) |
| return create_response(error_code, "DLCX", trans_id); |
| |
| if (!endp->allocated) { |
| LOGP(DMGCP, LOGL_ERROR, "Endpoint is not used. 0x%x\n", ENDPOINT_NUMBER(endp)); |
| return create_response(400, "DLCX", trans_id); |
| } |
| |
| MSG_TOKENIZE_START |
| switch (msg->l3h[line_start]) { |
| case 'C': { |
| if (verify_call_id(endp, (const char *)&msg->l3h[line_start + 3]) != 0) |
| goto error3; |
| break; |
| } |
| case 'I': { |
| if (verify_ci(endp, (const char *)&msg->l3h[line_start + 3]) != 0) |
| goto error3; |
| break; |
| case 'Z': |
| silent = strcmp("noanswer", (const char *)&msg->l3h[line_start + 3]) == 0; |
| break; |
| } |
| default: |
| LOGP(DMGCP, LOGL_NOTICE, "Unhandled option: '%c'/%d on 0x%x\n", |
| msg->l3h[line_start], msg->l3h[line_start], |
| ENDPOINT_NUMBER(endp)); |
| break; |
| } |
| MSG_TOKENIZE_END |
| |
| /* policy CB */ |
| if (cfg->policy_cb) { |
| switch (cfg->policy_cb(cfg, ENDPOINT_NUMBER(endp), MGCP_ENDP_DLCX, trans_id)) { |
| case MGCP_POLICY_REJECT: |
| LOGP(DMGCP, LOGL_NOTICE, "DLCX rejected by policy on 0x%x\n", |
| ENDPOINT_NUMBER(endp)); |
| if (silent) |
| goto out_silent; |
| return create_response(400, "DLCX", trans_id); |
| break; |
| case MGCP_POLICY_DEFER: |
| /* stop processing */ |
| delete_transcoder(endp); |
| return NULL; |
| break; |
| case MGCP_POLICY_CONT: |
| /* just continue */ |
| break; |
| } |
| } |
| |
| /* free the connection */ |
| LOGP(DMGCP, LOGL_DEBUG, "Deleted endpoint on: 0x%x Server: %s:%u\n", |
| ENDPOINT_NUMBER(endp), inet_ntoa(endp->net_end.addr), ntohs(endp->net_end.rtp_port)); |
| |
| delete_transcoder(endp); |
| mgcp_free_endp(endp); |
| if (cfg->change_cb) |
| cfg->change_cb(cfg, ENDPOINT_NUMBER(endp), MGCP_ENDP_DLCX); |
| |
| if (silent) |
| goto out_silent; |
| return create_response(250, "DLCX", trans_id); |
| |
| error: |
| LOGP(DMGCP, LOGL_ERROR, "Malformed line: %s on 0x%x with: line_start: %d %d\n", |
| hexdump(msg->l3h, msgb_l3len(msg)), |
| ENDPOINT_NUMBER(endp), line_start, i); |
| return create_response(error_code, "DLCX", trans_id); |
| |
| error3: |
| return create_response(error_code, "DLCX", trans_id); |
| |
| out_silent: |
| return NULL; |
| } |
| |
| static struct msgb *handle_rsip(struct mgcp_config *cfg, struct msgb *msg) |
| { |
| if (cfg->reset_cb) |
| cfg->reset_cb(cfg); |
| return NULL; |
| } |
| |
| struct mgcp_config *mgcp_config_alloc(void) |
| { |
| struct mgcp_config *cfg; |
| |
| cfg = talloc_zero(NULL, struct mgcp_config); |
| if (!cfg) { |
| LOGP(DMGCP, LOGL_FATAL, "Failed to allocate config.\n"); |
| return NULL; |
| } |
| |
| cfg->source_port = 2427; |
| cfg->source_addr = talloc_strdup(cfg, "0.0.0.0"); |
| cfg->audio_name = talloc_strdup(cfg, "AMR/8000"); |
| cfg->audio_payload = 126; |
| cfg->transcoder_remote_base = 4000; |
| |
| cfg->bts_ports.base_port = RTP_PORT_DEFAULT; |
| cfg->net_ports.base_port = RTP_PORT_NET_DEFAULT; |
| |
| return cfg; |
| } |
| |
| static void mgcp_rtp_end_reset(struct mgcp_rtp_end *end) |
| { |
| if (end->local_alloc == PORT_ALLOC_DYNAMIC) { |
| mgcp_free_rtp_port(end); |
| end->local_port = 0; |
| } |
| |
| end->packets = 0; |
| memset(&end->addr, 0, sizeof(end->addr)); |
| end->rtp_port = end->rtcp_port = 0; |
| end->payload_type = -1; |
| end->local_alloc = -1; |
| } |
| |
| static void mgcp_rtp_end_init(struct mgcp_rtp_end *end) |
| { |
| mgcp_rtp_end_reset(end); |
| end->rtp.fd = -1; |
| end->rtcp.fd = -1; |
| } |
| |
| int mgcp_endpoints_allocate(struct mgcp_config *cfg) |
| { |
| int i; |
| |
| /* Initialize all endpoints */ |
| cfg->endpoints = _talloc_zero_array(cfg, |
| sizeof(struct mgcp_endpoint), |
| cfg->number_endpoints, "endpoints"); |
| if (!cfg->endpoints) |
| return -1; |
| |
| for (i = 0; i < cfg->number_endpoints; ++i) { |
| cfg->endpoints[i].ci = CI_UNUSED; |
| cfg->endpoints[i].cfg = cfg; |
| mgcp_rtp_end_init(&cfg->endpoints[i].net_end); |
| mgcp_rtp_end_init(&cfg->endpoints[i].bts_end); |
| mgcp_rtp_end_init(&cfg->endpoints[i].trans_net); |
| mgcp_rtp_end_init(&cfg->endpoints[i].trans_bts); |
| } |
| |
| return 0; |
| } |
| |
| void mgcp_free_endp(struct mgcp_endpoint *endp) |
| { |
| LOGP(DMGCP, LOGL_DEBUG, "Deleting endpoint on: 0x%x\n", ENDPOINT_NUMBER(endp)); |
| endp->ci = CI_UNUSED; |
| endp->allocated = 0; |
| |
| if (endp->callid) { |
| talloc_free(endp->callid); |
| endp->callid = NULL; |
| } |
| |
| if (endp->local_options) { |
| talloc_free(endp->local_options); |
| endp->local_options = NULL; |
| } |
| |
| mgcp_rtp_end_reset(&endp->bts_end); |
| mgcp_rtp_end_reset(&endp->net_end); |
| mgcp_rtp_end_reset(&endp->trans_net); |
| mgcp_rtp_end_reset(&endp->trans_bts); |
| endp->is_transcoded = 0; |
| |
| memset(&endp->net_state, 0, sizeof(endp->net_state)); |
| memset(&endp->bts_state, 0, sizeof(endp->bts_state)); |
| |
| endp->conn_mode = endp->orig_mode = MGCP_CONN_NONE; |
| endp->allow_patch = 0; |
| |
| memset(&endp->taps, 0, sizeof(endp->taps)); |
| } |
| |
| static int send_trans(struct mgcp_config *cfg, const char *buf, int len) |
| { |
| struct sockaddr_in addr; |
| |
| memset(&addr, 0, sizeof(addr)); |
| addr.sin_family = AF_INET; |
| addr.sin_addr = cfg->transcoder_in; |
| addr.sin_port = htons(2427); |
| return sendto(cfg->gw_fd.bfd.fd, buf, len, 0, |
| (struct sockaddr *) &addr, sizeof(addr)); |
| } |
| |
| static void send_msg(struct mgcp_endpoint *endp, int endpoint, int port, |
| const char *msg, const char *mode) |
| { |
| char buf[2096]; |
| int len; |
| |
| /* hardcoded to AMR right now, we do not know the real type at this point */ |
| len = snprintf(buf, sizeof(buf), |
| "%s 42 %x@mgw MGCP 1.0\r\n" |
| "C: 4256\r\n" |
| "M: %s\r\n" |
| "\r\n" |
| "c=IN IP4 %s\r\n" |
| "m=audio %d RTP/AVP %d\r\n" |
| "a=rtpmap:%d %s\r\n", |
| msg, endpoint, mode, endp->cfg->source_addr, |
| port, endp->cfg->audio_payload, |
| endp->cfg->audio_payload, endp->cfg->audio_name); |
| |
| if (len < 0) |
| return; |
| |
| buf[sizeof(buf) - 1] = '\0'; |
| |
| send_trans(endp->cfg, buf, len); |
| } |
| |
| static void send_dlcx(struct mgcp_endpoint *endp, int endpoint) |
| { |
| char buf[2096]; |
| int len; |
| |
| len = snprintf(buf, sizeof(buf), |
| "DLCX 43 %x@mgw MGCP 1.0\r\n" |
| "C: 4256\r\n" |
| , endpoint); |
| |
| if (len < 0) |
| return; |
| |
| buf[sizeof(buf) - 1] = '\0'; |
| |
| send_trans(endp->cfg, buf, len); |
| } |
| |
| static void create_transcoder(struct mgcp_endpoint *endp) |
| { |
| int port; |
| int in_endp = ENDPOINT_NUMBER(endp); |
| int out_endp = endp_back_channel(in_endp); |
| |
| if (!endp->is_transcoded) |
| return; |
| |
| send_msg(endp, in_endp, endp->trans_bts.local_port, "CRCX", "sendrecv"); |
| send_msg(endp, in_endp, endp->trans_bts.local_port, "MDCX", "sendrecv"); |
| send_msg(endp, out_endp, endp->trans_net.local_port, "CRCX", "sendrecv"); |
| send_msg(endp, out_endp, endp->trans_net.local_port, "MDCX", "sendrecv"); |
| |
| port = rtp_calculate_port(in_endp, endp->cfg->transcoder_remote_base); |
| endp->trans_bts.rtp_port = htons(port); |
| endp->trans_bts.rtcp_port = htons(port + 1); |
| |
| port = rtp_calculate_port(out_endp, endp->cfg->transcoder_remote_base); |
| endp->trans_net.rtp_port = htons(port); |
| endp->trans_net.rtcp_port = htons(port + 1); |
| } |
| |
| static void delete_transcoder(struct mgcp_endpoint *endp) |
| { |
| int in_endp = ENDPOINT_NUMBER(endp); |
| int out_endp = endp_back_channel(in_endp); |
| |
| if (!endp->is_transcoded) |
| return; |
| |
| send_dlcx(endp, in_endp); |
| send_dlcx(endp, out_endp); |
| } |
| |
| int mgcp_reset_transcoder(struct mgcp_config *cfg) |
| { |
| if (!cfg->transcoder_ip) |
| return 0; |
| |
| static const char mgcp_reset[] = { |
| "RSIP 1 13@mgw MGCP 1.0\r\n" |
| }; |
| |
| return send_trans(cfg, mgcp_reset, sizeof mgcp_reset -1); |
| } |