[mgcp] Prepare to do MGCP over TCP and inside the bsc_msc_ip process
* Separate main process and protocol handling into two parts.
* Change the protocol handling to work with UDP and TCP connection
* This will allow to speak MGCP over TCP between the BSC MUX and
the real BSC.
diff --git a/openbsc/src/mgcp/mgcp_protocol.c b/openbsc/src/mgcp/mgcp_protocol.c
new file mode 100644
index 0000000..fe82fb5
--- /dev/null
+++ b/openbsc/src/mgcp/mgcp_protocol.c
@@ -0,0 +1,1114 @@
+/* A Media Gateway Control Protocol Media Gateway: RFC 3435 */
+/* The protocol implementation */
+
+/*
+ * (C) 2009 by Holger Hans Peter Freyther <zecke@selfish.org>
+ * (C) 2009 by on-waves.com
+ * 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 <sys/socket.h>
+#include <arpa/inet.h>
+
+#include <openbsc/debug.h>
+#include <openbsc/msgb.h>
+#include <openbsc/talloc.h>
+#include <openbsc/gsm_data.h>
+#include <openbsc/select.h>
+#include <openbsc/mgcp.h>
+#include <openbsc/telnet_interface.h>
+
+#include <vty/command.h>
+#include <vty/vty.h>
+
+#warning "Make use of the rtp proxy code"
+
+static int source_port = 2427;
+static const char *local_ip = NULL;
+static const char *source_addr = "0.0.0.0";
+static unsigned int number_endpoints = 0;
+static const char *bts_ip = NULL;
+static struct in_addr bts_in;
+static const char *audio_name = "GSM-EFR/8000";
+static int audio_payload = 97;
+static int audio_loop = 0;
+static int early_bind = 0;
+
+static char *forward_ip = NULL;
+static int forward_port = 0;
+
+enum mgcp_connection_mode {
+ MGCP_CONN_NONE = 0,
+ MGCP_CONN_RECV_ONLY = 1,
+ MGCP_CONN_SEND_ONLY = 2,
+ MGCP_CONN_RECV_SEND = MGCP_CONN_RECV_ONLY | MGCP_CONN_SEND_ONLY,
+};
+
+enum {
+ DEST_NETWORK = 0,
+ DEST_BTS = 1,
+};
+
+enum {
+ PROTO_RTP,
+ PROTO_RTCP,
+};
+
+#define CI_UNUSED 0
+static unsigned int last_call_id = 0;
+
+struct mgcp_endpoint {
+ int ci;
+ char *callid;
+ char *local_options;
+ int conn_mode;
+
+ /* the local rtp port we are binding to */
+ int rtp_port;
+
+ /*
+ * RTP mangling:
+ * - we get RTP and RTCP to us and need to forward to the BTS
+ * - we get RTP and RTCP from the BTS and forward to the network
+ */
+ struct bsc_fd local_rtp;
+ struct bsc_fd local_rtcp;
+
+ struct in_addr remote;
+ struct in_addr bts;
+
+ /* in network byte order */
+ int net_rtp, net_rtcp;
+ int bts_rtp, bts_rtcp;
+};
+
+static struct mgcp_endpoint *endpoints = NULL;
+#define ENDPOINT_NUMBER(endp) abs(endp - endpoints)
+
+/**
+ * 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; \
+ } \
+ }
+
+
+struct mgcp_msg_ptr {
+ unsigned int start;
+ unsigned int length;
+};
+
+struct mgcp_request {
+ char *name;
+ int (*handle_request) (int fd, struct msgb *msg, struct sockaddr_in *source);
+ char *debug_name;
+};
+
+#define MGCP_REQUEST(NAME, REQ, DEBUG_NAME) \
+ { .name = NAME, .handle_request = REQ, .debug_name = DEBUG_NAME },
+
+static int handle_audit_endpoint(int fd, struct msgb *msg, struct sockaddr_in *source);
+static int handle_create_con(int fd, struct msgb *msg, struct sockaddr_in *source);
+static int handle_delete_con(int fd, struct msgb *msg, struct sockaddr_in *source);
+static int handle_modify_con(int fd, struct msgb *msg, struct sockaddr_in *source);
+
+static int generate_call_id()
+{
+ int i;
+
+ /* use the call id */
+ ++last_call_id;
+
+ /* handle wrap around */
+ if (last_call_id == CI_UNUSED)
+ ++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 < number_endpoints; ++i)
+ if (endpoints[i].ci == last_call_id)
+ return generate_call_id();
+
+ return last_call_id;
+}
+
+/* FIXIME/TODO: need to have a list of pending transactions and check that */
+static unsigned int generate_transaction_id()
+{
+ return abs(rand());
+}
+
+static int udp_send(int fd, struct in_addr *addr, int port, char *buf, int len)
+{
+ struct sockaddr_in out;
+ out.sin_family = AF_INET;
+ out.sin_port = port;
+ memcpy(&out.sin_addr, addr, sizeof(*addr));
+
+ return sendto(fd, buf, len, 0, (struct sockaddr *)&out, sizeof(out));
+}
+
+/*
+ * There is data coming. We will have to figure out if it
+ * came from the BTS or the MediaGateway of the MSC. On top
+ * of that we need to figure out if it was RTP or RTCP.
+ *
+ * Currently we do not communicate with the BSC so we have
+ * no idea where the BTS is listening for RTP and need to
+ * do the classic routing trick. Wait for the first packet
+ * from the BTS and then go ahead.
+ */
+static int rtp_data_cb(struct bsc_fd *fd, unsigned int what)
+{
+ char buf[4096];
+ struct sockaddr_in addr;
+ socklen_t slen = sizeof(addr);
+ struct mgcp_endpoint *endp;
+ int rc, dest, proto;
+
+ endp = (struct mgcp_endpoint *) fd->data;
+
+ rc = recvfrom(fd->fd, &buf, sizeof(buf), 0,
+ (struct sockaddr *) &addr, &slen);
+ if (rc < 0) {
+ DEBUGP(DMGCP, "Failed to receive message on: 0x%x\n",
+ ENDPOINT_NUMBER(endp));
+ return -1;
+ }
+
+ /* do not forward aynthing... maybe there is a packet from the bts */
+ if (endp->ci == CI_UNUSED) {
+ DEBUGP(DMGCP, "Unknown message on endpoint: 0x%x\n", ENDPOINT_NUMBER(endp));
+ return -1;
+ }
+
+ /*
+ * Figure out where to forward it to. This code assumes that we
+ * have received the Connection Modify and know who is a legitimate
+ * partner. According to the spec we could attempt to forward even
+ * after the Create Connection but we will not as we are not really
+ * able to tell if this is legitimate.
+ */
+ #warning "Slight spec violation. With connection mode recvonly we should attempt to forward."
+ dest = memcmp(&addr.sin_addr, &endp->remote, sizeof(addr.sin_addr)) == 0 &&
+ (endp->net_rtp == addr.sin_port || endp->net_rtcp == addr.sin_port)
+ ? DEST_BTS : DEST_NETWORK;
+ proto = fd == &endp->local_rtp ? PROTO_RTP : PROTO_RTCP;
+
+ /* We have no idea who called us, maybe it is the BTS. */
+ if (dest == DEST_NETWORK && (endp->bts_rtp == 0 || forward_ip)) {
+ /* it was the BTS... */
+ if (!bts_ip || memcmp(&addr.sin_addr, &bts_in, sizeof(bts_in)) == 0) {
+ if (fd == &endp->local_rtp) {
+ endp->bts_rtp = addr.sin_port;
+ } else {
+ endp->bts_rtcp = addr.sin_port;
+ }
+
+ endp->bts = addr.sin_addr;
+ DEBUGP(DMGCP, "Found BTS for endpoint: 0x%x on port: %d/%d\n",
+ ENDPOINT_NUMBER(endp), ntohs(endp->bts_rtp), ntohs(endp->bts_rtcp));
+ }
+ }
+
+ /* dispatch */
+ if (audio_loop)
+ dest = !dest;
+
+ if (dest == DEST_NETWORK) {
+ return udp_send(fd->fd, &endp->remote,
+ proto == PROTO_RTP ? endp->net_rtp : endp->net_rtcp,
+ buf, rc);
+ } else {
+ return udp_send(fd->fd, &endp->bts,
+ proto == PROTO_RTP ? endp->bts_rtp : endp->bts_rtcp,
+ buf, rc);
+ }
+}
+
+static int create_bind(struct bsc_fd *fd, int port)
+{
+ struct sockaddr_in addr;
+ int on = 1;
+
+ fd->fd = socket(AF_INET, SOCK_DGRAM, 0);
+ if (fd->fd < 0)
+ return -1;
+
+ setsockopt(fd->fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
+ memset(&addr, 0, sizeof(addr));
+ addr.sin_family = AF_INET;
+ addr.sin_port = htons(port);
+ inet_aton(source_addr, &addr.sin_addr);
+
+ if (bind(fd->fd, (struct sockaddr *) &addr, sizeof(addr)) < 0)
+ return -1;
+
+ return 0;
+}
+
+static int bind_rtp(struct mgcp_endpoint *endp)
+{
+ if (create_bind(&endp->local_rtp, endp->rtp_port) != 0) {
+ DEBUGP(DMGCP, "Failed to create RTP port: %d on 0x%x\n",
+ endp->rtp_port, ENDPOINT_NUMBER(endp));
+ goto cleanup0;
+ }
+
+ if (create_bind(&endp->local_rtcp, endp->rtp_port + 1) != 0) {
+ DEBUGP(DMGCP, "Failed to create RTCP port: %d on 0x%x\n",
+ endp->rtp_port + 1, ENDPOINT_NUMBER(endp));
+ goto cleanup1;
+ }
+
+ endp->local_rtp.cb = rtp_data_cb;
+ endp->local_rtp.data = endp;
+ endp->local_rtp.when = BSC_FD_READ;
+ if (bsc_register_fd(&endp->local_rtp) != 0) {
+ DEBUGP(DMGCP, "Failed to register RTP port %d on 0x%x\n",
+ endp->rtp_port, ENDPOINT_NUMBER(endp));
+ goto cleanup2;
+ }
+
+ endp->local_rtcp.cb = rtp_data_cb;
+ endp->local_rtcp.data = endp;
+ endp->local_rtcp.when = BSC_FD_READ;
+ if (bsc_register_fd(&endp->local_rtcp) != 0) {
+ DEBUGP(DMGCP, "Failed to register RTCP port %d on 0x%x\n",
+ endp->rtp_port + 1, ENDPOINT_NUMBER(endp));
+ goto cleanup3;
+ }
+
+ return 0;
+
+cleanup3:
+ bsc_unregister_fd(&endp->local_rtp);
+cleanup2:
+ close(endp->local_rtcp.fd);
+ endp->local_rtcp.fd = -1;
+cleanup1:
+ close(endp->local_rtp.fd);
+ endp->local_rtp.fd = -1;
+cleanup0:
+ return -1;
+}
+
+/*
+ * 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")
+};
+
+static int send_response_with_data(int fd, int code, const char *msg, const char *trans,
+ const char *data, struct sockaddr_in *source)
+{
+ char buf[4096];
+ int len;
+
+ if (data) {
+ len = snprintf(buf, sizeof(buf), "%d %s\n%s", code, trans, data);
+ } else {
+ len = snprintf(buf, sizeof(buf), "%d %s\n", code, trans);
+ }
+ DEBUGP(DMGCP, "Sending response: code: %d for '%s'\n", code, msg);
+
+ if (source)
+ return sendto(fd, buf, len, 0, (struct sockaddr *)source, sizeof(*source));
+ else
+ return write(fd, buf, len);
+}
+
+static int send_response(int fd, int code, const char *msg,
+ const char *trans, struct sockaddr_in *source)
+{
+ return send_response_with_data(fd, code, msg, trans, NULL, source);
+}
+
+static int send_with_sdp(int fd, struct mgcp_endpoint *endp, const char *msg, const char *trans_id, struct sockaddr_in *source)
+{
+ const char *addr = local_ip;
+ char sdp_record[4096];
+
+ if (!addr)
+ addr = source_addr;
+
+ snprintf(sdp_record, sizeof(sdp_record) - 1,
+ "I: %d\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->rtp_port,
+ audio_payload, audio_payload, audio_name);
+ return send_response_with_data(fd, 200, msg, trans_id, sdp_record, source);
+}
+
+/* send a static record */
+int mgcp_send_rsip(int fd, struct sockaddr_in *source)
+{
+ char reset[4096];
+ int len, rc;
+
+ len = snprintf(reset, sizeof(reset) - 1,
+ "RSIP %u *@mgw MGCP 1.0\n"
+ "RM: restart\n", generate_transaction_id());
+ if (source)
+ rc = sendto(fd, reset, len, 0, (struct sockaddr *) source, sizeof(*source));
+ else
+ rc = write(fd, reset, len);
+
+ if (rc < 0) {
+ DEBUGP(DMGCP, "Failed to send RSIP: %d\n", rc);
+ }
+
+ return rc;
+}
+
+/*
+ * handle incoming messages:
+ * - this can be a command (four letters, space, transaction id)
+ * - or a response (three numbers, space, transaction id)
+ */
+int mgcp_handle_message(int fd, struct msgb *msg, struct sockaddr_in *source)
+{
+ int code;
+
+ if (msg->len < 4) {
+ DEBUGP(DMGCP, "mgs too short: %d\n", msg->len);
+ return -1;
+ }
+
+ /* attempt to treat it as a response */
+ if (sscanf((const char *)&msg->data[0], "%3d %*s", &code) == 1) {
+ DEBUGP(DMGCP, "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->data[0], 4) == 0) {
+ handled = 1;
+ mgcp_requests[i].handle_request(fd, msg, source);
+ }
+ if (!handled) {
+ DEBUGP(DMGCP, "MSG with type: '%.4s' not handled\n", &msg->data[0]);
+ }
+ }
+
+ return 0;
+}
+
+/* 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(const char *mgcp)
+{
+ char *endptr = NULL;
+ unsigned int gw = INT_MAX;
+
+ gw = strtoul(mgcp, &endptr, 16);
+ if (gw == 0 || gw >= number_endpoints || strcmp(endptr, "@mgw") != 0) {
+ DEBUGP(DMGCP, "Not able to find endpoint: '%s'\n", mgcp);
+ return NULL;
+ }
+
+ return &endpoints[gw];
+}
+
+static int analyze_header(struct msgb *msg, struct mgcp_msg_ptr *ptr, int size,
+ const char **transaction_id, struct mgcp_endpoint **endp)
+{
+ int found;
+
+ if (size < 3) {
+ DEBUGP(DMGCP, "Not enough space in ptr\n");
+ return -1;
+ }
+
+ found = find_msg_pointers(msg, ptr, size);
+
+ if (found < 3) {
+ DEBUGP(DMGCP, "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) {
+ DEBUGP(DMGCP, "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];
+ *endp = find_endpoint((const char *)&msg->l3h[ptr[1].start]);
+ return *endp == NULL;
+}
+
+static int verify_call_id(const struct mgcp_endpoint *endp,
+ const char *callid)
+{
+ if (strcmp(endp->callid, callid) != 0) {
+ DEBUGP(DMGCP, "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)
+{
+ if (atoi(ci) != endp->ci) {
+ DEBUGP(DMGCP, "ConnectionIdentifiers do not match on 0x%x. %d != %s\n",
+ ENDPOINT_NUMBER(endp), endp->ci, ci);
+ return -1;
+ }
+
+ return 0;
+}
+
+static int handle_audit_endpoint(int fd, struct msgb *msg, struct sockaddr_in *source)
+{
+ struct mgcp_msg_ptr data_ptrs[6];
+ int found, response;
+ const char *trans_id;
+ struct mgcp_endpoint *endp;
+
+ found = analyze_header(msg, data_ptrs, ARRAY_SIZE(data_ptrs), &trans_id, &endp);
+ if (found != 0)
+ response = 500;
+ else
+ response = 200;
+
+ return send_response(fd, response, "AUEP", trans_id, source);
+}
+
+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 {
+ DEBUGP(DMGCP, "Unknown connection mode: '%s'\n", msg);
+ ret = -1;
+ }
+
+ return ret;
+}
+
+static int handle_create_con(int fd, struct msgb *msg, struct sockaddr_in *source)
+{
+ struct mgcp_msg_ptr data_ptrs[6];
+ int found, i, line_start;
+ const char *trans_id;
+ struct mgcp_endpoint *endp;
+ int error_code = 500;
+
+ found = analyze_header(msg, data_ptrs, ARRAY_SIZE(data_ptrs), &trans_id, &endp);
+ if (found != 0)
+ return send_response(fd, 500, "CRCX", trans_id, source);
+
+ if (endp->ci != CI_UNUSED) {
+ DEBUGP(DMGCP, "Endpoint is already used. 0x%x\n", ENDPOINT_NUMBER(endp));
+ return send_response(fd, 500, "CRCX", trans_id, source);
+ }
+
+ /* parse CallID C: and LocalParameters L: */
+ MSG_TOKENIZE_START
+ switch (msg->l3h[line_start]) {
+ case 'L':
+ endp->local_options = talloc_strdup(endpoints,
+ (const char *)&msg->l3h[line_start + 3]);
+ break;
+ case 'C':
+ endp->callid = talloc_strdup(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;
+ }
+ break;
+ default:
+ DEBUGP(DMGCP, "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_rtp = endp->net_rtcp = endp->bts_rtp = endp->bts_rtcp = 0;
+
+ /* set to zero until we get the info */
+ memset(&endp->remote, 0, sizeof(endp->remote));
+
+ /* bind to the port now */
+ endp->rtp_port = rtp_calculate_port(ENDPOINT_NUMBER(endp), rtp_base_port);
+ if (!early_bind && bind_rtp(endp) != 0)
+ goto error2;
+
+ /* assign a local call identifier or fail */
+ endp->ci = generate_call_id();
+ if (endp->ci == CI_UNUSED)
+ goto error2;
+
+ DEBUGP(DMGCP, "Creating endpoint on: 0x%x CI: %u port: %u\n",
+ ENDPOINT_NUMBER(endp), endp->ci, endp->rtp_port);
+ return send_with_sdp(fd, endp, "CRCX", trans_id, source);
+error:
+ DEBUGP(DMGCP, "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 send_response(fd, error_code, "CRCX", trans_id, source);
+
+error2:
+ DEBUGP(DMGCP, "Resource error on 0x%x\n", ENDPOINT_NUMBER(endp));
+ return send_response(fd, error_code, "CRCX", trans_id, source);
+}
+
+static int handle_modify_con(int fd, struct msgb *msg, struct sockaddr_in *source)
+{
+ struct mgcp_msg_ptr data_ptrs[6];
+ int found, i, line_start;
+ const char *trans_id;
+ struct mgcp_endpoint *endp;
+ int error_code = 500;
+
+ found = analyze_header(msg, data_ptrs, ARRAY_SIZE(data_ptrs), &trans_id, &endp);
+ if (found != 0)
+ return send_response(fd, error_code, "MDCX", trans_id, source);
+
+ if (endp->ci == CI_UNUSED) {
+ DEBUGP(DMGCP, "Endpoint is not holding a connection. 0x%x\n", ENDPOINT_NUMBER(endp));
+ return send_response(fd, error_code, "MDCX", trans_id, source);
+ }
+
+ 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;
+ }
+ 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;
+ const char *param = (const char *)&msg->l3h[line_start];
+
+ if (sscanf(param, "m=audio %d RTP/AVP %*d", &port) == 1) {
+ endp->net_rtp = htons(port);
+ endp->net_rtcp = htons(port + 1);
+ }
+ 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->remote);
+ }
+ break;
+ }
+ default:
+ DEBUGP(DMGCP, "Unhandled option: '%c'/%d on 0x%x\n",
+ msg->l3h[line_start], msg->l3h[line_start],
+ ENDPOINT_NUMBER(endp));
+ break;
+ }
+ MSG_TOKENIZE_END
+
+ /* modify */
+ DEBUGP(DMGCP, "Modified endpoint on: 0x%x Server: %s:%u\n",
+ ENDPOINT_NUMBER(endp), inet_ntoa(endp->remote), endp->net_rtp);
+ return send_with_sdp(fd, endp, "MDCX", trans_id, source);
+
+error:
+ DEBUGP(DMGCP, "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 send_response(fd, error_code, "MDCX", trans_id, source);
+
+error3:
+ return send_response(fd, error_code, "MDCX", trans_id, source);
+}
+
+static int handle_delete_con(int fd, struct msgb *msg, struct sockaddr_in *source)
+{
+ struct mgcp_msg_ptr data_ptrs[6];
+ int found, i, line_start;
+ const char *trans_id;
+ struct mgcp_endpoint *endp;
+ int error_code = 500;
+
+ found = analyze_header(msg, data_ptrs, ARRAY_SIZE(data_ptrs), &trans_id, &endp);
+ if (found != 0)
+ return send_response(fd, error_code, "DLCX", trans_id, source);
+
+ if (endp->ci == CI_UNUSED) {
+ DEBUGP(DMGCP, "Endpoint is not used. 0x%x\n", ENDPOINT_NUMBER(endp));
+ return send_response(fd, error_code, "DLCX", trans_id, source);
+ }
+
+ 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;
+ }
+ default:
+ DEBUGP(DMGCP, "Unhandled option: '%c'/%d on 0x%x\n",
+ msg->l3h[line_start], msg->l3h[line_start],
+ ENDPOINT_NUMBER(endp));
+ break;
+ }
+ MSG_TOKENIZE_END
+
+
+ /* free the connection */
+ DEBUGP(DMGCP, "Deleting endpoint on: 0x%x\n", ENDPOINT_NUMBER(endp));
+ endp->ci= CI_UNUSED;
+ talloc_free(endp->callid);
+ talloc_free(endp->local_options);
+
+ if (!early_bind) {
+ bsc_unregister_fd(&endp->local_rtp);
+ bsc_unregister_fd(&endp->local_rtcp);
+ }
+
+ endp->net_rtp = endp->net_rtcp = endp->bts_rtp = endp->bts_rtcp = 0;
+
+ return send_response(fd, 250, "DLCX", trans_id, source);
+
+error:
+ DEBUGP(DMGCP, "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 send_response(fd, error_code, "DLCX", trans_id, source);
+
+error3:
+ return send_response(fd, error_code, "DLCX", trans_id, source);
+}
+
+/*
+ * vty code for mgcp below
+ */
+struct cmd_node mgcp_node = {
+ MGCP_NODE,
+ "%s(mgcp)#",
+ 1,
+};
+
+static int config_write_mgcp(struct vty *vty)
+{
+ vty_out(vty, "mgcp%s", VTY_NEWLINE);
+ if (local_ip)
+ vty_out(vty, " local ip %s%s", local_ip, VTY_NEWLINE);
+ if (bts_ip)
+ vty_out(vty, " bts ip %s%s", bts_ip, VTY_NEWLINE);
+ vty_out(vty, " bind ip %s%s", source_addr, VTY_NEWLINE);
+ vty_out(vty, " bind port %u%s", source_port, VTY_NEWLINE);
+ vty_out(vty, " bind early %u%s", !!early_bind, VTY_NEWLINE);
+ vty_out(vty, " rtp base %u%s", rtp_base_port, VTY_NEWLINE);
+ vty_out(vty, " sdp audio payload number %u%s", audio_payload, VTY_NEWLINE);
+ vty_out(vty, " sdp audio payload name %s%s", audio_name, VTY_NEWLINE);
+ vty_out(vty, " loop %u%s", !!audio_loop, VTY_NEWLINE);
+ vty_out(vty, " endpoints %u%s", number_endpoints, VTY_NEWLINE);
+ if (forward_ip)
+ vty_out(vty, " forward audio ip %s%s", forward_ip, VTY_NEWLINE);
+ if (forward_port != 0)
+ vty_out(vty, " forward audio port %d%s", forward_port, VTY_NEWLINE);
+
+ return CMD_SUCCESS;
+}
+
+DEFUN(show_mcgp, show_mgcp_cmd, "show mgcp",
+ SHOW_STR "Display information about the MGCP Media Gateway")
+{
+ int i;
+
+ vty_out(vty, "MGCP is up and running with %u endpoints:%s", number_endpoints - 1, VTY_NEWLINE);
+ for (i = 1; i < number_endpoints; ++i) {
+ struct mgcp_endpoint *endp = &endpoints[i];
+ vty_out(vty, " Endpoint 0x%.2x: CI: %d net: %u/%u bts: %u/%u%s",
+ i, endp->ci,
+ ntohs(endp->net_rtp), ntohs(endp->net_rtcp),
+ ntohs(endp->bts_rtp), ntohs(endp->bts_rtcp), VTY_NEWLINE);
+ }
+
+ return CMD_SUCCESS;
+}
+
+DEFUN(cfg_mgcp,
+ cfg_mgcp_cmd,
+ "mgcp",
+ "Configure the MGCP")
+{
+ vty->node = MGCP_NODE;
+ return CMD_SUCCESS;
+}
+
+DEFUN(cfg_mgcp_local_ip,
+ cfg_mgcp_local_ip_cmd,
+ "local ip IP",
+ "Set the IP to be used in SDP records")
+{
+ local_ip = talloc_strdup(tall_bsc_ctx, argv[0]);
+ return CMD_SUCCESS;
+}
+
+DEFUN(cfg_mgcp_bts_ip,
+ cfg_mgcp_bts_ip_cmd,
+ "bts ip IP",
+ "Set the IP of the BTS for RTP forwarding")
+{
+ bts_ip = talloc_strdup(tall_bsc_ctx, argv[0]);
+ inet_aton(bts_ip, &bts_in);
+ return CMD_SUCCESS;
+}
+
+DEFUN(cfg_mgcp_bind_ip,
+ cfg_mgcp_bind_ip_cmd,
+ "bind ip IP",
+ "Bind the MGCP to this local addr")
+{
+ source_addr = talloc_strdup(tall_bsc_ctx, argv[0]);
+ return CMD_SUCCESS;
+}
+
+DEFUN(cfg_mgcp_bind_port,
+ cfg_mgcp_bind_port_cmd,
+ "bind port <0-65534>",
+ "Bind the MGCP to this port")
+{
+ unsigned int port = atoi(argv[0]);
+ if (port > 65534) {
+ vty_out(vty, "%% wrong bind port '%s'%s", argv[0], VTY_NEWLINE);
+ return CMD_WARNING;
+ }
+
+ source_port = port;
+ return CMD_SUCCESS;
+}
+
+DEFUN(cfg_mgcp_bind_early,
+ cfg_mgcp_bind_early_cmd,
+ "bind early (0|1)",
+ "Bind all RTP ports early")
+{
+ unsigned int bind = atoi(argv[0]);
+ if (bind != 0 && bind != 1) {
+ vty_out(vty, "%% param must be 0 or 1.%s", VTY_NEWLINE);
+ return CMD_WARNING;
+ }
+
+ early_bind = bind == 1;
+ return CMD_SUCCESS;
+}
+
+DEFUN(cfg_mgcp_rtp_base_port,
+ cfg_mgcp_rtp_base_port_cmd,
+ "rtp base <0-65534>",
+ "Base port to use")
+{
+ unsigned int port = atoi(argv[0]);
+ if (port > 65534) {
+ vty_out(vty, "%% wrong base port '%s'%s", argv[0], VTY_NEWLINE);
+ return CMD_WARNING;
+ }
+
+ rtp_base_port = port;
+ return CMD_SUCCESS;
+}
+
+DEFUN(cfg_mgcp_sdp_payload_number,
+ cfg_mgcp_sdp_payload_number_cmd,
+ "sdp audio payload number <1-255>",
+ "Set the audio codec to use")
+{
+ unsigned int payload = atoi(argv[0]);
+ if (payload > 255) {
+ vty_out(vty, "%% wrong payload number '%s'%s", argv[0], VTY_NEWLINE);
+ return CMD_WARNING;
+ }
+
+ audio_payload = payload;
+ return CMD_SUCCESS;
+}
+
+DEFUN(cfg_mgcp_sdp_payload_name,
+ cfg_mgcp_sdp_payload_name_cmd,
+ "sdp audio payload name NAME",
+ "Set the audio name to use")
+{
+ audio_name = talloc_strdup(tall_bsc_ctx, argv[0]);
+ return CMD_SUCCESS;
+}
+
+DEFUN(cfg_mgcp_loop,
+ cfg_mgcp_loop_cmd,
+ "loop (0|1)",
+ "Loop the audio")
+{
+ audio_loop = atoi(argv[0]);
+ return CMD_SUCCESS;
+}
+
+DEFUN(cfg_mgcp_number_endp,
+ cfg_mgcp_number_endp_cmd,
+ "number endpoints <0-65534>",
+ "The number of endpoints to allocate. This is not dynamic.")
+{
+ /* + 1 as we start counting at one */
+ number_endpoints = atoi(argv[0]) + 1;
+ return CMD_SUCCESS;
+}
+
+DEFUN(cfg_mgcp_forward_ip,
+ cfg_mgcp_forward_ip_cmd,
+ "forward audio ip IP",
+ "Forward packets from and to the IP. This disables most of the MGCP feature.")
+{
+ if (forward_ip)
+ talloc_free(forward_ip);
+ forward_ip = talloc_strdup(tall_bsc_ctx, argv[0]);
+ return CMD_SUCCESS;
+}
+
+DEFUN(cfg_mgcp_forward_port,
+ cfg_mgcp_forward_port_cmd,
+ "forward audio port <1-15000>",
+ "Forward packets from and to the port. This disables most of the MGCP feature.")
+{
+ forward_port = atoi(argv[0]);
+ return CMD_SUCCESS;
+}
+
+int mgcp_vty_init(void)
+{
+ install_element(VIEW_NODE, &show_mgcp_cmd);
+
+ install_element(CONFIG_NODE, &cfg_mgcp_cmd);
+ install_node(&mgcp_node, config_write_mgcp);
+ install_default(MGCP_NODE);
+ install_element(MGCP_NODE, &cfg_mgcp_local_ip_cmd);
+ install_element(MGCP_NODE, &cfg_mgcp_bts_ip_cmd);
+ install_element(MGCP_NODE, &cfg_mgcp_bind_ip_cmd);
+ install_element(MGCP_NODE, &cfg_mgcp_bind_port_cmd);
+ install_element(MGCP_NODE, &cfg_mgcp_bind_early_cmd);
+ install_element(MGCP_NODE, &cfg_mgcp_rtp_base_port_cmd);
+ install_element(MGCP_NODE, &cfg_mgcp_sdp_payload_number_cmd);
+ install_element(MGCP_NODE, &cfg_mgcp_sdp_payload_name_cmd);
+ install_element(MGCP_NODE, &cfg_mgcp_loop_cmd);
+ install_element(MGCP_NODE, &cfg_mgcp_number_endp_cmd);
+ install_element(MGCP_NODE, &cfg_mgcp_forward_ip_cmd);
+ install_element(MGCP_NODE, &cfg_mgcp_forward_port_cmd);
+ return 0;
+}
+
+int mgcp_parse_config(const char *config_file, struct gsm_network *dummy_network)
+{
+ int i, rc;
+
+ rc = vty_read_config_file(config_file);
+ if (rc < 0) {
+ fprintf(stderr, "Failed to parse the config file: '%s'\n", config_file);
+ return rc;
+ }
+
+
+ if (!bts_ip)
+ fprintf(stderr, "No BTS ip address specified. This will allow everyone to connect.\n");
+
+ endpoints = _talloc_zero_array(tall_bsc_ctx,
+ sizeof(struct mgcp_endpoint),
+ number_endpoints, "endpoints");
+ if (!endpoints) {
+ fprintf(stderr, "Failed to allocate endpoints: %d. Quitting.\n", number_endpoints);
+ return -1;
+ }
+
+ /* Initialize all endpoints */
+ for (i = 0; i < number_endpoints; ++i) {
+ endpoints[i].local_rtp.fd = -1;
+ endpoints[i].local_rtcp.fd = -1;
+ endpoints[i].ci = CI_UNUSED;
+ }
+
+ /*
+ * This application supports two modes.
+ * 1.) a true MGCP gateway with support for AUEP, CRCX, MDCX, DLCX
+ * 2.) plain forwarding of RTP packets on the endpoints.
+ * both modes are mutual exclusive
+ */
+ if (forward_ip) {
+ int port = rtp_base_port;
+ if (forward_port != 0)
+ port = forward_port;
+
+ if (!early_bind) {
+ DEBUGP(DMGCP, "Forwarding requires early bind.\n");
+ return -1;
+ }
+
+ /*
+ * Store the forward IP and assign a ci. For early bind
+ * the sockets will be created after this.
+ */
+ for (i = 1; i < number_endpoints; ++i) {
+ struct mgcp_endpoint *endp = &endpoints[i];
+ inet_aton(forward_ip, &endp->remote);
+ endp->ci = CI_UNUSED + 23;
+ endp->net_rtp = htons(rtp_calculate_port(ENDPOINT_NUMBER(endp), port));
+ endp->net_rtcp = htons(rtp_calculate_port(ENDPOINT_NUMBER(endp), port) + 1);
+ }
+
+ DEBUGP(DMGCP, "Configured for Audio Forwarding.\n");
+ }
+
+ /* early bind */
+ if (early_bind) {
+ for (i = 1; i < number_endpoints; ++i) {
+ struct mgcp_endpoint *endp = &endpoints[i];
+ endp->rtp_port = rtp_calculate_port(ENDPOINT_NUMBER(endp), rtp_base_port);
+ if (bind_rtp(endp) != 0)
+ return -1;
+ }
+ }
+
+ return !!forward_ip;
+}