2010-02-21 10:11:04 +00:00
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/* A Media Gateway Control Protocol Media Gateway: RFC 3435 */
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/* The protocol implementation */
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/*
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* (C) 2009-2010 by Holger Hans Peter Freyther <zecke@selfish.org>
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* (C) 2009-2010 by On-Waves
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* All Rights Reserved
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License along
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* with this program; if not, write to the Free Software Foundation, Inc.,
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* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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*/
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#include <string.h>
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2010-05-13 18:14:09 +00:00
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#include <stdlib.h>
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2010-02-21 10:11:04 +00:00
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#include <unistd.h>
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2010-02-26 12:42:58 +00:00
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#include <endian.h>
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2010-04-07 10:55:40 +00:00
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#include <errno.h>
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2010-02-21 10:11:04 +00:00
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#include <sys/socket.h>
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#include <arpa/inet.h>
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2010-02-26 19:16:37 +00:00
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#include <osmocore/msgb.h>
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#include <osmocore/select.h>
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2010-02-21 10:11:04 +00:00
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#include <openbsc/debug.h>
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#include <openbsc/mgcp.h>
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#include <openbsc/mgcp_internal.h>
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#warning "Make use of the rtp proxy code"
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2010-02-26 12:42:58 +00:00
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/* according to rtp_proxy.c RFC 3550 */
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struct rtp_hdr {
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#if __BYTE_ORDER == __LITTLE_ENDIAN
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2010-07-23 10:56:26 +00:00
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uint8_t csrc_count:4,
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2010-02-26 12:42:58 +00:00
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extension:1,
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padding:1,
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version:2;
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2010-07-23 10:56:26 +00:00
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uint8_t payload_type:7,
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2010-02-26 12:42:58 +00:00
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marker:1;
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#elif __BYTE_ORDER == __BIG_ENDIAN
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2010-07-23 10:56:26 +00:00
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uint8_t version:2,
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2010-02-26 12:42:58 +00:00
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padding:1,
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extension:1,
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csrc_count:4;
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2010-07-23 10:56:26 +00:00
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uint8_t marker:1,
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2010-02-26 12:42:58 +00:00
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payload_type:7;
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#endif
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2010-07-23 10:56:01 +00:00
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uint16_t sequence;
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2010-07-23 10:55:38 +00:00
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uint32_t timestamp;
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uint32_t ssrc;
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2010-02-26 12:42:58 +00:00
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} __attribute__((packed));
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2010-02-21 10:11:04 +00:00
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enum {
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DEST_NETWORK = 0,
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DEST_BTS = 1,
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};
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enum {
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PROTO_RTP,
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PROTO_RTCP,
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};
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2010-04-21 13:25:13 +00:00
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#define DUMMY_LOAD 0x23
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2010-02-21 10:11:04 +00:00
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static int udp_send(int fd, struct in_addr *addr, int port, char *buf, int len)
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{
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struct sockaddr_in out;
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out.sin_family = AF_INET;
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out.sin_port = port;
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memcpy(&out.sin_addr, addr, sizeof(*addr));
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return sendto(fd, buf, len, 0, (struct sockaddr *)&out, sizeof(out));
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}
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2010-04-21 13:25:13 +00:00
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int mgcp_send_dummy(struct mgcp_endpoint *endp)
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{
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static char buf[] = { DUMMY_LOAD };
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return udp_send(endp->local_rtp.fd, &endp->remote,
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endp->net_rtp, buf, 1);
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}
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2010-08-04 13:51:31 +00:00
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static void patch_and_count(struct mgcp_rtp_state *state, int endp_no, int conn_mode,
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2010-08-04 13:45:39 +00:00
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struct sockaddr_in *addr, int payload, char *data, int len)
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2010-02-26 12:42:58 +00:00
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{
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2010-07-28 18:38:39 +00:00
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uint16_t seq;
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2010-08-03 14:35:50 +00:00
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uint32_t timestamp;
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2010-02-26 12:42:58 +00:00
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struct rtp_hdr *rtp_hdr;
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if (len < sizeof(*rtp_hdr))
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return;
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2010-07-28 18:38:39 +00:00
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rtp_hdr = (struct rtp_hdr *) data;
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seq = ntohs(rtp_hdr->sequence);
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2010-08-03 14:35:50 +00:00
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timestamp = ntohl(rtp_hdr->timestamp);
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2010-07-28 18:38:39 +00:00
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2010-08-03 11:59:04 +00:00
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if (!state->initialized) {
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2010-08-03 14:35:50 +00:00
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state->seq_no = seq - 1;
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state->ssrc = state->orig_ssrc = rtp_hdr->ssrc;
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2010-08-03 11:59:04 +00:00
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state->initialized = 1;
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2010-08-03 14:35:50 +00:00
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state->last_timestamp = timestamp;
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} else if (state->ssrc != rtp_hdr->ssrc) {
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state->ssrc = rtp_hdr->ssrc;
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state->seq_offset = (state->seq_no + 1) - seq;
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state->timestamp_offset = state->last_timestamp - timestamp;
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2010-08-04 13:49:19 +00:00
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//state->patch = 1;
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2010-08-04 13:45:39 +00:00
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LOGP(DMGCP, LOGL_NOTICE,
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2010-08-04 13:51:31 +00:00
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"The SSRC changed on %d SSRC: %u offset: %d from %s:%d in %d\n",
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2010-08-04 13:45:39 +00:00
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endp_no, state->ssrc, state->seq_offset,
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2010-08-04 13:51:31 +00:00
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inet_ntoa(addr->sin_addr), ntohs(addr->sin_port), conn_mode);
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2010-08-03 14:35:50 +00:00
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}
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/* apply the offset and store it back to the packet */
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2010-08-03 15:36:57 +00:00
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if (state->patch) {
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seq += state->seq_offset;
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rtp_hdr->sequence = htons(seq);
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rtp_hdr->ssrc = state->orig_ssrc;
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2010-08-03 14:35:50 +00:00
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2010-08-03 15:36:57 +00:00
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timestamp += state->timestamp_offset;
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rtp_hdr->timestamp = htonl(timestamp);
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}
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2010-08-03 14:35:50 +00:00
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/* seq changed, now compare if we have lost something */
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if (state->seq_no + 1u != seq)
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2010-08-03 11:59:04 +00:00
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state->lost_no = abs(seq - (state->seq_no + 1));
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state->seq_no = seq;
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2010-07-28 18:38:39 +00:00
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2010-08-03 14:35:50 +00:00
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state->last_timestamp = timestamp;
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2010-04-06 09:15:50 +00:00
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if (payload < 0)
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return;
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2010-02-26 12:42:58 +00:00
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rtp_hdr->payload_type = payload;
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}
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2010-02-21 10:11:04 +00:00
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/*
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* There is data coming. We will have to figure out if it
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* came from the BTS or the MediaGateway of the MSC. On top
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* of that we need to figure out if it was RTP or RTCP.
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*
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* Currently we do not communicate with the BSC so we have
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* no idea where the BTS is listening for RTP and need to
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* do the classic routing trick. Wait for the first packet
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* from the BTS and then go ahead.
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*/
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static int rtp_data_cb(struct bsc_fd *fd, unsigned int what)
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{
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char buf[4096];
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struct sockaddr_in addr;
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socklen_t slen = sizeof(addr);
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struct mgcp_endpoint *endp;
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struct mgcp_config *cfg;
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int rc, dest, proto;
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endp = (struct mgcp_endpoint *) fd->data;
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cfg = endp->cfg;
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rc = recvfrom(fd->fd, &buf, sizeof(buf), 0,
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(struct sockaddr *) &addr, &slen);
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if (rc < 0) {
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2010-04-07 10:55:40 +00:00
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LOGP(DMGCP, LOGL_ERROR, "Failed to receive message on: 0x%x errno: %d/%s\n",
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ENDPOINT_NUMBER(endp), errno, strerror(errno));
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2010-02-21 10:11:04 +00:00
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return -1;
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}
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/* do not forward aynthing... maybe there is a packet from the bts */
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2010-03-01 17:53:05 +00:00
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if (endp->ci == CI_UNUSED)
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2010-02-21 10:11:04 +00:00
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return -1;
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/*
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* Figure out where to forward it to. This code assumes that we
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* have received the Connection Modify and know who is a legitimate
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* partner. According to the spec we could attempt to forward even
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* after the Create Connection but we will not as we are not really
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* able to tell if this is legitimate.
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*/
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#warning "Slight spec violation. With connection mode recvonly we should attempt to forward."
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dest = memcmp(&addr.sin_addr, &endp->remote, sizeof(addr.sin_addr)) == 0 &&
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2010-04-30 05:32:05 +00:00
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(endp->net_rtp == addr.sin_port || endp->net_rtcp == addr.sin_port)
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2010-02-21 10:11:04 +00:00
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? DEST_BTS : DEST_NETWORK;
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proto = fd == &endp->local_rtp ? PROTO_RTP : PROTO_RTCP;
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/* We have no idea who called us, maybe it is the BTS. */
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if (dest == DEST_NETWORK && (endp->bts_rtp == 0 || cfg->forward_ip)) {
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/* it was the BTS... */
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2010-04-01 05:56:04 +00:00
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if (!cfg->bts_ip
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|| memcmp(&addr.sin_addr, &cfg->bts_in, sizeof(cfg->bts_in)) == 0
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|| memcmp(&addr.sin_addr, &endp->bts, sizeof(endp->bts)) == 0) {
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2010-02-21 10:11:04 +00:00
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if (fd == &endp->local_rtp) {
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endp->bts_rtp = addr.sin_port;
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} else {
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endp->bts_rtcp = addr.sin_port;
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}
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endp->bts = addr.sin_addr;
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2010-04-09 16:53:01 +00:00
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LOGP(DMGCP, LOGL_NOTICE, "Found BTS for endpoint: 0x%x on port: %d/%d of %s\n",
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ENDPOINT_NUMBER(endp), ntohs(endp->bts_rtp), ntohs(endp->bts_rtcp),
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inet_ntoa(addr.sin_addr));
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2010-04-21 13:25:13 +00:00
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2010-02-21 10:11:04 +00:00
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}
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}
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2010-05-13 18:18:59 +00:00
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/* throw away the dummy message */
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2010-04-22 04:14:51 +00:00
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if (rc == 1 && buf[0] == DUMMY_LOAD) {
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LOGP(DMGCP, LOGL_NOTICE, "Filtered dummy on 0x%x\n",
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ENDPOINT_NUMBER(endp));
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return 0;
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}
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2010-04-07 07:37:17 +00:00
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/* do this before the loop handling */
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if (dest == DEST_NETWORK)
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++endp->in_bts;
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else
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++endp->in_remote;
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2010-05-13 18:18:59 +00:00
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/* For loop toggle the destination and then dispatch. */
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2010-02-21 10:11:04 +00:00
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if (cfg->audio_loop)
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dest = !dest;
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2010-08-02 18:27:21 +00:00
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/* Loop based on the conn_mode, maybe undoing the above */
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if (endp->conn_mode == MGCP_CONN_LOOPBACK)
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dest = !dest;
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2010-02-21 10:11:04 +00:00
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if (dest == DEST_NETWORK) {
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2010-05-22 14:06:13 +00:00
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if (proto == PROTO_RTP)
|
2010-08-03 11:59:04 +00:00
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patch_and_count(&endp->bts_state,
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2010-08-04 13:51:31 +00:00
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endp->net_payload_type, endp->conn_mode,
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2010-08-04 13:45:39 +00:00
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&addr,
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ENDPOINT_NUMBER(endp), buf, rc);
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2010-02-21 10:11:04 +00:00
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return udp_send(fd->fd, &endp->remote,
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proto == PROTO_RTP ? endp->net_rtp : endp->net_rtcp,
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buf, rc);
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} else {
|
2010-05-22 14:06:13 +00:00
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if (proto == PROTO_RTP)
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2010-08-03 11:59:04 +00:00
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patch_and_count(&endp->net_state,
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2010-08-04 13:51:31 +00:00
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endp->bts_payload_type, endp->conn_mode,
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2010-08-04 13:45:39 +00:00
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&addr,
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ENDPOINT_NUMBER(endp), buf, rc);
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2010-02-21 10:11:04 +00:00
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return udp_send(fd->fd, &endp->bts,
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proto == PROTO_RTP ? endp->bts_rtp : endp->bts_rtcp,
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buf, rc);
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}
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}
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static int create_bind(const char *source_addr, struct bsc_fd *fd, int port)
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{
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struct sockaddr_in addr;
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int on = 1;
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fd->fd = socket(AF_INET, SOCK_DGRAM, 0);
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if (fd->fd < 0) {
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LOGP(DMGCP, LOGL_ERROR, "Failed to create UDP port.\n");
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return -1;
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}
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setsockopt(fd->fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
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memset(&addr, 0, sizeof(addr));
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addr.sin_family = AF_INET;
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addr.sin_port = htons(port);
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inet_aton(source_addr, &addr.sin_addr);
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if (bind(fd->fd, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
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return -1;
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}
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return 0;
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}
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|
|
|
2010-05-31 02:22:00 +00:00
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static int set_ip_tos(int fd, int tos)
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{
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int ret;
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ret = setsockopt(fd, IPPROTO_IP, IP_TOS,
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&tos, sizeof(tos));
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return ret != 0;
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}
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|
2010-02-21 10:11:04 +00:00
|
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static int bind_rtp(struct mgcp_endpoint *endp)
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|
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{
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struct mgcp_config *cfg = endp->cfg;
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if (create_bind(cfg->source_addr, &endp->local_rtp, endp->rtp_port) != 0) {
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LOGP(DMGCP, LOGL_ERROR, "Failed to create RTP port: %s:%d on 0x%x\n",
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cfg->source_addr, endp->rtp_port, ENDPOINT_NUMBER(endp));
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|
goto cleanup0;
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}
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if (create_bind(cfg->source_addr, &endp->local_rtcp, endp->rtp_port + 1) != 0) {
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|
|
LOGP(DMGCP, LOGL_ERROR, "Failed to create RTCP port: %s:%d on 0x%x\n",
|
|
|
|
cfg->source_addr, endp->rtp_port + 1, ENDPOINT_NUMBER(endp));
|
|
|
|
goto cleanup1;
|
|
|
|
}
|
|
|
|
|
2010-07-27 12:34:45 +00:00
|
|
|
set_ip_tos(endp->local_rtp.fd, cfg->endp_dscp);
|
|
|
|
set_ip_tos(endp->local_rtcp.fd, cfg->endp_dscp);
|
2010-05-31 02:22:00 +00:00
|
|
|
|
2010-02-21 10:11:04 +00:00
|
|
|
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) {
|
|
|
|
LOGP(DMGCP, LOGL_ERROR, "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) {
|
|
|
|
LOGP(DMGCP, LOGL_ERROR, "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;
|
|
|
|
}
|
|
|
|
|
|
|
|
int mgcp_bind_rtp_port(struct mgcp_endpoint *endp, int rtp_port)
|
|
|
|
{
|
|
|
|
endp->rtp_port = rtp_port;
|
|
|
|
return bind_rtp(endp);
|
|
|
|
}
|