diff --git a/openbsc/contrib/mgcp_server.py b/openbsc/contrib/mgcp_server.py new file mode 100755 index 000000000..cf3ef3845 --- /dev/null +++ b/openbsc/contrib/mgcp_server.py @@ -0,0 +1,54 @@ +#!/usr/bin/env python +# Simple server for mgcp... send audit, receive response.. + +import socket, time + +MGCP_GATEWAY_PORT = 2427 +MGCP_CALLAGENT_PORT = 2727 + +rsip_resp = """200 321321332\r\n""" +audit_packet = """AUEP %d 13@mgw MGCP 1.0\r\n""" +crcx_packet = """CRCX %d 14@mgw MGCP 1.0\r\nC: 4a84ad5d25f\r\nL: p:20, a:GSM-EFR, nt:IN\r\nM: recvonly\r\n""" +dlcx_packet = """DLCX %d 14@mgw MGCP 1.0\r\nC: 4a84ad5d25f\r\nI: %d\r\n""" +mdcx_packet = """MDCX %d 14@mgw MGCP 1.0\r\nC: 4a84ad5d25f\r\nI: %d\r\nL: p:20, a:GSM-EFR, nt:IN\r\nM: recvonly\r\n\r\nv=0\r\no=- 258696477 0 IN IP4 172.16.1.107\r\ns=-\r\nc=IN IP4 172.16.1.107\r\nt=0 0\r\nm=audio 4400 RTP/AVP 127\r\na=rtpmap:127 GSM-EFR/8000/1\r\na=ptime:20\r\na=recvonly\r\nm=image 4402 udptl t38\r\na=T38FaxVersion:0\r\na=T38MaxBitRate:14400\r\n""" + +def hexdump(src, length=8): + """Recipe is from http://code.activestate.com/recipes/142812/""" + result = [] + digits = 4 if isinstance(src, unicode) else 2 + for i in xrange(0, len(src), length): + s = src[i:i+length] + hexa = b' '.join(["%0*X" % (digits, ord(x)) for x in s]) + text = b''.join([x if 0x20 <= ord(x) < 0x7F else b'.' for x in s]) + result.append( b"%04X %-*s %s" % (i, length*(digits + 1), hexa, text) ) + return b'\n'.join(result) + +server_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM) +server_socket.bind(("127.0.0.1", MGCP_CALLAGENT_PORT)) +server_socket.setblocking(0) + + +def send_receive(packet): + server_socket.sendto(packet, ("127.0.0.1", MGCP_GATEWAY_PORT)) + try: + data, addr = server_socket.recvfrom(4096) + print hexdump(data), addr + except socket.error: + pass + +def generate_tid(): + import random + return random.randint(0, 65123) + + + +i = 1 +while True: + send_receive(rsip_resp) + send_receive(audit_packet) + send_receive(crcx_packet % generate_tid() ) + send_receive(mdcx_packet % (generate_tid(), i)) + send_receive(dlcx_packet % (generate_tid(), i)) + i = i + 1 + + time.sleep(3) diff --git a/openbsc/include/openbsc/mgcp.h b/openbsc/include/openbsc/mgcp.h new file mode 100644 index 000000000..fa6224c12 --- /dev/null +++ b/openbsc/include/openbsc/mgcp.h @@ -0,0 +1,48 @@ +/* A Media Gateway Control Protocol Media Gateway: RFC 3435 */ + +/* + * (C) 2009 by Holger Hans Peter Freyther + * (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. + * + */ + +unsigned int rtp_base_port = 4000; + +/** + * Calculate the RTP audio port for the given multiplex + * and the direction. This allows a semi static endpoint + * to port calculation removing the need for the BSC + * and the MediaGateway to communicate. + * + * Port usage explained: + * base + (multiplex * 2) + 0 == local port to wait for network packets + * base + (multiplex * 2) + 1 == local port for rtcp + * + * The above port will receive packets from the BTS that need + * to be patched and forwarded to the network. + * The above port will receive packets from the network that + * need to be patched and forwarded to the BTS. + * + * We assume to have a static BTS IP address so we can differentiate + * network and BTS. + * + */ +int rtp_calculate_port(int multiplex, int base) +{ + return base + (multiplex * 2); +} diff --git a/openbsc/include/vty/command.h b/openbsc/include/vty/command.h index 9daa2d62d..10a60add5 100644 --- a/openbsc/include/vty/command.h +++ b/openbsc/include/vty/command.h @@ -106,6 +106,7 @@ enum node_type { TRX_NODE, TS_NODE, SUBSCR_NODE, + MGCP_NODE, }; /* Node which has some commands and prompt string and configuration diff --git a/openbsc/src/Makefile.am b/openbsc/src/Makefile.am index 79120081d..7651132b6 100644 --- a/openbsc/src/Makefile.am +++ b/openbsc/src/Makefile.am @@ -1,7 +1,8 @@ INCLUDES = $(all_includes) -I$(top_srcdir)/include AM_CFLAGS=-Wall -sbin_PROGRAMS = bsc_hack bs11_config ipaccess-find ipaccess-config isdnsync +sbin_PROGRAMS = bsc_hack bs11_config ipaccess-find ipaccess-config isdnsync \ + isdnsync bsc_mgcp noinst_LIBRARIES = libbsc.a libmsc.a libvty.a libsccp.a noinst_HEADERS = vty/cardshell.h @@ -32,3 +33,6 @@ ipaccess_config_SOURCES = ipaccess-config.c ipaccess_config_LDADD = libbsc.a libmsc.a libbsc.a libvty.a -ldl -ldbi $(LIBCRYPT) isdnsync_SOURCES = isdnsync.c + +bsc_mgcp_SOURCES = bsc_mgcp.c msgb.c talloc.c debug.c select.c timer.c +bsc_mgcp_LDADD = libvty.a diff --git a/openbsc/src/bsc_mgcp.c b/openbsc/src/bsc_mgcp.c new file mode 100644 index 000000000..8b59b31cb --- /dev/null +++ b/openbsc/src/bsc_mgcp.c @@ -0,0 +1,1117 @@ +/* A Media Gateway Control Protocol Media Gateway: RFC 3435 */ + +/* + * (C) 2009 by Holger Hans Peter Freyther + * (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 +#include +#include +#include +#include +#include +#include + +#include +#include + +#include +#include +#include +#include +#include +#include + +#include +#include + +/* this is here for the vty... it will never be called */ +void subscr_put() { abort(); } +void vty_event() { } + +#define _GNU_SOURCE +#include + +#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 const unsigned int number_endpoints = 32 + 1; +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 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, +}; + +#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, is_remote; + + 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; + } + + /* + * 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." + is_remote = memcmp(&addr.sin_addr, &endp->remote, sizeof(addr.sin_addr)) == 0; + if (is_remote) { + if (endp->rtp == addr.sin_port) { + return _send(fd->fd, &bts_in, endp->bts_rtp, buf, rc); + } else if (endp->rtcp == addr.sin_port) { + return _send(fd->fd, &bts_in, endp->bts_rtcp, buf, rc); + } else { + DEBUGP(DMGCP, "Unknown remote port. Not able to forward on 0x%x port: %d\n", + ENDPOINT_NUMBER(endp), ntohs(addr.sin_port)); + } + + return -1; + } + + /* We have no idea who called us, maybe it is the BTS. */ + if (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; + endp->bts_rtcp = htons(ntohs(addr.sin_port) + 1); + } else { + endp->bts_rtp = htons(ntohs(addr.sin_port) - 1); + endp->bts_rtcp = addr.sin_port; + } + + DEBUGP(DMGCP, "Found BTS for endpoint: 0x%x on port: %d\n", + ENDPOINT_NUMBER(endp), ntohs(endp->bts_rtp)); + } + } + + if (endp->bts_rtp == 0 || endp->conn_mode == MGCP_CONN_RECV_ONLY) { + DEBUGP(DMGCP, "Not forwarding data from possible BTS conn: %d on 0x%x\n", + endp->conn_mode, ENDPOINT_NUMBER(endp)); + return -1; + } + + if (fd == &endp->local_rtp) { + return _send(fd->fd, &endp->remote, endp->rtp, buf, rc); + } else { + return _send(fd->fd, &endp->remote, endp->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)); + endp->bts_rtp = endp->bts_rtcp = 0; + endp->rtp = endp->rtcp = 0; + + 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 + + + /* 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); + } + + 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, " rtp base %u%s", rtp_base_port, 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; +} + +static void mgcp_vty_init() +{ + cmd_init(1); + vty_init(); + + 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); +} + +int main(int argc, char** argv) +{ + struct sockaddr_in addr; + int on = 1, i, rc; + + tall_bsc_ctx = talloc_named_const(NULL, 1, "mgcp-callagent"); + handle_options(argc, argv); + + mgcp_vty_init(); + 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; +} diff --git a/openbsc/src/mgcp.cfg b/openbsc/src/mgcp.cfg new file mode 100644 index 000000000..c4da05162 --- /dev/null +++ b/openbsc/src/mgcp.cfg @@ -0,0 +1,17 @@ +! +! MGCP configuration hand edited +! ! +password foo +! +line vty + no login +! +mgcp + local ip 172.23.23.23 + bts ip 192.168.100.100 + bind ip 0.0.0.0 + bind port 2427 + bind early 1 + rtp base 4000 + sdp audio payload number 97 + sdp audio payload name GSM-EFR/8000