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-rw-r--r--src/libmgcp/mgcp_protocol.c1102
1 files changed, 1102 insertions, 0 deletions
diff --git a/src/libmgcp/mgcp_protocol.c b/src/libmgcp/mgcp_protocol.c
new file mode 100644
index 00000000..ba290dd9
--- /dev/null
+++ b/src/libmgcp/mgcp_protocol.c
@@ -0,0 +1,1102 @@
+/* A Media Gateway Control Protocol Media Gateway: RFC 3435 */
+/* The protocol implementation */
+
+/*
+ * (C) 2009-2011 by Holger Hans Peter Freyther <zecke@selfish.org>
+ * (C) 2009-2011 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 <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#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 struct msgb *handle_noti_req(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->trunk.number_endpoints; ++i)
+ if (cfg->trunk.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")
+ MGCP_REQUEST("RQNT", handle_noti_req, "NotificationRequest")
+
+ /* 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 *txt,
+ 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%s\r\n%s", code, trans, txt, data);
+ } else {
+ len = snprintf((char *) res->data, 2048, "%d %s%s\r\n", code, trans, txt);
+ }
+
+ 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_ok_response(int code, const char *msg, const char *trans)
+{
+ return mgcp_create_response_with_data(code, " OK", msg, trans, NULL);
+}
+
+static struct msgb *create_err_response(int code, const char *msg, const char *trans)
+{
+ return mgcp_create_response_with_data(code, " FAIL", 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->tcfg->audio_name);
+ return mgcp_create_response_with_data(200, " OK", 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;
+}
+
+/**
+ * We have a null terminated string with the endpoint name here. We only
+ * support two kinds. Simple ones as seen on the BSC level and the ones
+ * seen on the trunk side.
+ */
+static struct mgcp_endpoint *find_e1_endpoint(struct mgcp_config *cfg,
+ const char *mgcp)
+{
+ char *rest = NULL;
+ struct mgcp_trunk_config *tcfg;
+ int trunk, endp;
+
+ trunk = strtoul(mgcp + 6, &rest, 10);
+ if (rest == NULL || rest[0] != '/' || trunk < 1) {
+ LOGP(DMGCP, LOGL_ERROR, "Wrong trunk name '%s'\n", mgcp);
+ return NULL;
+ }
+
+ endp = strtoul(rest + 1, &rest, 10);
+ if (rest == NULL || rest[0] != '@') {
+ LOGP(DMGCP, LOGL_ERROR, "Wrong endpoint name '%s'\n", mgcp);
+ return NULL;
+ }
+
+ /* signalling is on timeslot 1 */
+ if (endp == 1)
+ return NULL;
+
+ tcfg = mgcp_trunk_num(cfg, trunk);
+ if (!tcfg) {
+ LOGP(DMGCP, LOGL_ERROR, "The trunk %d is not declared.\n", trunk);
+ return NULL;
+ }
+
+ if (!tcfg->endpoints) {
+ LOGP(DMGCP, LOGL_ERROR, "Endpoints of trunk %d not allocated.\n", trunk);
+ return NULL;
+ }
+
+ if (endp < 1 || endp >= tcfg->number_endpoints) {
+ LOGP(DMGCP, LOGL_ERROR, "Failed to find endpoint '%s'\n", mgcp);
+ return NULL;
+ }
+
+ return &tcfg->endpoints[endp];
+}
+
+static struct mgcp_endpoint *find_endpoint(struct mgcp_config *cfg, const char *mgcp)
+{
+ char *endptr = NULL;
+ unsigned int gw = INT_MAX;
+
+ if (strncmp(mgcp, "ds/e1", 5) == 0) {
+ return find_e1_endpoint(cfg, mgcp);
+ } else {
+ gw = strtoul(mgcp, &endptr, 16);
+ if (gw > 0 && gw < cfg->trunk.number_endpoints && strcmp(endptr, "@mgw") == 0)
+ return &cfg->trunk.endpoints[gw];
+ }
+
+ LOGP(DMGCP, LOGL_ERROR, "Not able to find endpoint: '%s'\n", mgcp);
+ return NULL;
+}
+
+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;
+ 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)
+ return create_err_response(500, "AUEP", trans_id);
+ else
+ return create_ok_response(200, "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 && endp->tcfg->trunk_type == MGCP_TRUNK_VIRTUAL) {
+ 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_trunk_config *tcfg;
+ 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_err_response(510, "CRCX", trans_id);
+
+ tcfg = endp->tcfg;
+
+ if (endp->allocated) {
+ if (tcfg->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(tcfg, ENDPOINT_NUMBER(endp));
+ } else {
+ LOGP(DMGCP, LOGL_ERROR, "Endpoint is already used. 0x%x\n",
+ ENDPOINT_NUMBER(endp));
+ return create_err_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(tcfg->endpoints,
+ (const char *)&msg->l3h[line_start + 3]);
+ break;
+ case 'C':
+ endp->callid = talloc_strdup(tcfg->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 = tcfg->audio_payload;
+
+ /* policy CB */
+ if (cfg->policy_cb) {
+ switch (cfg->policy_cb(tcfg, 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_err_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(tcfg, 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_err_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_err_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_err_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_err_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(endp->tcfg, 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_err_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(endp->tcfg, 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_err_response(error_code, "MDCX", trans_id);
+
+error3:
+ return create_err_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_err_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_err_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(endp->tcfg, 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_err_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(endp->tcfg, ENDPOINT_NUMBER(endp), MGCP_ENDP_DLCX);
+
+ if (silent)
+ goto out_silent;
+ return create_ok_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_err_response(error_code, "DLCX", trans_id);
+
+error3:
+ return create_err_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;
+}
+
+/*
+ * 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_config *cfg, struct msgb *msg)
+{
+ struct mgcp_msg_ptr data_ptrs[6];
+ const char *trans_id;
+ struct mgcp_endpoint *endp;
+ int found;
+
+ found = mgcp_analyze_header(cfg, msg, data_ptrs, ARRAY_SIZE(data_ptrs), &trans_id, &endp);
+ if (found != 0)
+ return create_err_response(400, "RQNT", trans_id);
+
+ if (!endp->allocated) {
+ LOGP(DMGCP, LOGL_ERROR, "Endpoint is not used. 0x%x\n", ENDPOINT_NUMBER(endp));
+ return create_err_response(400, "RQNT", trans_id);
+ }
+ return create_ok_response(200, "RQNT", trans_id);
+}
+
+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->transcoder_remote_base = 4000;
+
+ cfg->bts_ports.base_port = RTP_PORT_DEFAULT;
+ cfg->net_ports.base_port = RTP_PORT_NET_DEFAULT;
+
+ /* default trunk handling */
+ cfg->trunk.cfg = cfg;
+ cfg->trunk.trunk_nr = 0;
+ cfg->trunk.trunk_type = MGCP_TRUNK_VIRTUAL;
+ cfg->trunk.audio_name = talloc_strdup(cfg, "AMR/8000");
+ cfg->trunk.audio_payload = 126;
+
+ INIT_LLIST_HEAD(&cfg->trunks);
+
+ return cfg;
+}
+
+struct mgcp_trunk_config *mgcp_trunk_alloc(struct mgcp_config *cfg, int nr)
+{
+ struct mgcp_trunk_config *trunk;
+
+ trunk = talloc_zero(cfg, struct mgcp_trunk_config);
+ if (!trunk) {
+ LOGP(DMGCP, LOGL_ERROR, "Failed to allocate.\n");
+ return NULL;
+ }
+
+ trunk->cfg = cfg;
+ trunk->trunk_type = MGCP_TRUNK_E1;
+ trunk->trunk_nr = nr;
+ trunk->audio_name = talloc_strdup(cfg, "AMR/8000");
+ trunk->audio_payload = 126;
+ trunk->number_endpoints = 33;
+ llist_add_tail(&trunk->entry, &cfg->trunks);
+ return trunk;
+}
+
+struct mgcp_trunk_config *mgcp_trunk_num(struct mgcp_config *cfg, int index)
+{
+ struct mgcp_trunk_config *trunk;
+
+ llist_for_each_entry(trunk, &cfg->trunks, entry)
+ if (trunk->trunk_nr == index)
+ return trunk;
+
+ return NULL;
+}
+
+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_trunk_config *tcfg)
+{
+ int i;
+
+ /* Initialize all endpoints */
+ tcfg->endpoints = _talloc_zero_array(tcfg->cfg,
+ sizeof(struct mgcp_endpoint),
+ tcfg->number_endpoints, "endpoints");
+ if (!tcfg->endpoints)
+ return -1;
+
+ for (i = 0; i < tcfg->number_endpoints; ++i) {
+ tcfg->endpoints[i].ci = CI_UNUSED;
+ tcfg->endpoints[i].cfg = tcfg->cfg;
+ tcfg->endpoints[i].tcfg = tcfg;
+ mgcp_rtp_end_init(&tcfg->endpoints[i].net_end);
+ mgcp_rtp_end_init(&tcfg->endpoints[i].bts_end);
+ mgcp_rtp_end_init(&tcfg->endpoints[i].trans_net);
+ mgcp_rtp_end_init(&tcfg->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->tcfg->audio_payload,
+ endp->tcfg->audio_payload, endp->tcfg->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);
+}