| /* A Media Gateway Control Protocol Media Gateway: RFC 3435 */ |
| |
| /* |
| * (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> |
| |
| /* this is here for the vty... it will never be called */ |
| void subscr_put() { abort(); } |
| |
| #define _GNU_SOURCE |
| #include <getopt.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 struct bsc_fd bfd; |
| static unsigned int number_endpoints = 0; |
| static const char *bts_ip = NULL; |
| static struct in_addr bts_in; |
| static int first_request = 1; |
| 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 *config_file = "mgcp.cfg"; |
| |
| /* used by msgb and mgcp */ |
| void *tall_bsc_ctx = NULL; |
| |
| 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 */ |
| 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; |
| |
| /* in network byte order */ |
| int rtp, 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; |
| void (*handle_request) (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 void handle_audit_endpoint(struct msgb *msg, struct sockaddr_in *source); |
| static void handle_create_con(struct msgb *msg, struct sockaddr_in *source); |
| static void handle_delete_con(struct msgb *msg, struct sockaddr_in *source); |
| static void handle_modify_con(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 _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) |
| 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 |
| ? 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) { |
| /* it was the BTS... */ |
| if (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; |
| } |
| |
| 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 _send(fd->fd, &endp->remote, |
| proto == PROTO_RTP ? endp->rtp : endp->rtcp, |
| buf, rc); |
| } else { |
| return _send(fd->fd, &bts_in, |
| 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) |
| { |
| /* set to zero until we get the info */ |
| memset(&endp->remote, 0, sizeof(endp->remote)); |
| |
| 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 void send_response_with_data(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); |
| |
| sendto(bfd.fd, buf, len, 0, (struct sockaddr *)source, sizeof(*source)); |
| } |
| |
| static void send_response(int code, const char *msg, const char *trans, struct sockaddr_in *source) |
| { |
| send_response_with_data(code, msg, trans, NULL, source); |
| } |
| |
| static void send_with_sdp(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(200, msg, trans_id, sdp_record, source); |
| } |
| |
| /* send a static record */ |
| static void send_rsip(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()); |
| rc = sendto(bfd.fd, reset, len, 0, (struct sockaddr *) source, sizeof(*source)); |
| if (rc < 0) { |
| DEBUGP(DMGCP, "Failed to send RSIP: %d\n", rc); |
| } |
| } |
| |
| /* |
| * handle incoming messages: |
| * - this can be a command (four letters, space, transaction id) |
| * - or a response (three numbers, space, transaction id) |
| */ |
| static void handle_message(struct msgb *msg, struct sockaddr_in *source) |
| { |
| int code; |
| |
| if (msg->len < 4) { |
| DEBUGP(DMGCP, "mgs too short: %d\n", msg->len); |
| return; |
| } |
| |
| /* 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(msg, source); |
| } |
| if (!handled) { |
| DEBUGP(DMGCP, "MSG with type: '%.4s' not handled\n", &msg->data[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 void handle_audit_endpoint(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(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 void handle_create_con(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(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(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->rtp = endp->rtcp = endp->bts_rtp = endp->bts_rtcp = 0; |
| |
| /* 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(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(error_code, "CRCX", trans_id, source); |
| |
| error2: |
| DEBUGP(DMGCP, "Resource error on 0x%x\n", ENDPOINT_NUMBER(endp)); |
| return send_response(error_code, "CRCX", trans_id, source); |
| } |
| |
| static void handle_modify_con(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(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(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->rtp = htons(port); |
| endp->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->rtp); |
| return send_with_sdp(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(error_code, "MDCX", trans_id, source); |
| |
| error3: |
| return send_response(error_code, "MDCX", trans_id, source); |
| } |
| |
| static void handle_delete_con(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(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(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->rtp = endp->rtcp = endp->bts_rtp = endp->bts_rtcp = 0; |
| |
| return send_response(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(error_code, "DLCX", trans_id, source); |
| |
| error3: |
| return send_response(error_code, "DLCX", trans_id, source); |
| } |
| |
| static void print_help() |
| { |
| printf("Some useful help...\n"); |
| printf(" -h --help is printing this text.\n"); |
| printf(" -c --config-file filename The config file to use.\n"); |
| } |
| |
| static void handle_options(int argc, char** argv) |
| { |
| while (1) { |
| int option_index = 0, c; |
| static struct option long_options[] = { |
| {"help", 0, 0, 'h'}, |
| {"config-file", 1, 0, 'c'}, |
| {0, 0, 0, 0}, |
| }; |
| |
| c = getopt_long(argc, argv, "hc:", long_options, &option_index); |
| |
| if (c == -1) |
| break; |
| |
| switch(c) { |
| case 'h': |
| print_help(); |
| exit(0); |
| break; |
| case 'c': |
| config_file = talloc_strdup(tall_bsc_ctx, optarg); |
| break; |
| default: |
| /* ignore */ |
| break; |
| }; |
| } |
| } |
| |
| static int read_call_agent(struct bsc_fd *fd, unsigned int what) |
| { |
| struct sockaddr_in addr; |
| socklen_t slen = sizeof(addr); |
| struct msgb *msg; |
| |
| msg = (struct msgb *) fd->data; |
| |
| /* read one less so we can use it as a \0 */ |
| int rc = recvfrom(bfd.fd, msg->data, msg->data_len - 1, 0, |
| (struct sockaddr *) &addr, &slen); |
| if (rc < 0) { |
| perror("Gateway failed to read"); |
| return -1; |
| } else if (slen > sizeof(addr)) { |
| fprintf(stderr, "Gateway received message from outerspace: %d %d\n", |
| slen, sizeof(addr)); |
| return -1; |
| } |
| |
| if (first_request) { |
| first_request = 0; |
| send_rsip(&addr); |
| return 0; |
| } |
| |
| /* handle message now */ |
| msg->l2h = msgb_put(msg, rc); |
| handle_message(msg, &addr); |
| msgb_reset(msg); |
| return 0; |
| } |
| |
| /* |
| * 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); |
| 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); |
| |
| 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->rtp), ntohs(endp->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; |
| } |
| |
| int bsc_vty_init(struct gsm_network *dummy) |
| { |
| cmd_init(1); |
| vty_init(); |
| |
| 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); |
| return 0; |
| } |
| |
| int main(int argc, char** argv) |
| { |
| struct gsm_network dummy_network; |
| struct sockaddr_in addr; |
| int on = 1, i, rc; |
| struct debug_target *stderr_target; |
| |
| tall_bsc_ctx = talloc_named_const(NULL, 1, "mgcp-callagent"); |
| |
| debug_init(); |
| stderr_target = debug_target_create_stderr(); |
| debug_add_target(stderr_target); |
| debug_set_all_filter(stderr_target, 1); |
| |
| handle_options(argc, argv); |
| |
| telnet_init(&dummy_network, 4243); |
| 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, "Need to specify the BTS ip address for RTP handling.\n"); |
| return -1; |
| } |
| |
| 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; |
| } |
| |
| /* initialize the socket */ |
| bfd.when = BSC_FD_READ; |
| bfd.cb = read_call_agent; |
| bfd.fd = socket(AF_INET, SOCK_DGRAM, 0); |
| if (bfd.fd < 0) { |
| perror("Gateway failed to listen"); |
| return -1; |
| } |
| |
| setsockopt(bfd.fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)); |
| |
| memset(&addr, 0, sizeof(addr)); |
| addr.sin_family = AF_INET; |
| addr.sin_port = htons(source_port); |
| inet_aton(source_addr, &addr.sin_addr); |
| |
| if (bind(bfd.fd, (struct sockaddr *) &addr, sizeof(addr)) < 0) { |
| perror("Gateway failed to bind"); |
| return -1; |
| } |
| |
| bfd.data = msgb_alloc(4096, "mgcp-msg"); |
| if (!bfd.data) { |
| fprintf(stderr, "Gateway memory error.\n"); |
| return -1; |
| } |
| |
| |
| if (bsc_register_fd(&bfd) != 0) { |
| DEBUGP(DMGCP, "Failed to register the fd\n"); |
| return -1; |
| } |
| |
| /* initialisation */ |
| srand(time(NULL)); |
| |
| /* 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; |
| } |
| } |
| |
| /* main loop */ |
| while (1) { |
| bsc_select_main(0); |
| } |
| |
| |
| return 0; |
| } |