1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
|
/*
* Some SDP file parsing...
*
* (C) 2009-2015 by Holger Hans Peter Freyther <zecke@selfish.org>
* (C) 2009-2014 by On-Waves
* All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation; either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
#include <openbsc/mgcp.h>
#include <openbsc/mgcp_internal.h>
#include <errno.h>
int mgcp_set_audio_info(void *ctx, struct mgcp_rtp_codec *codec,
int payload_type, const char *audio_name)
{
int rate = codec->rate;
int channels = codec->channels;
char audio_codec[64];
talloc_free(codec->subtype_name);
codec->subtype_name = NULL;
talloc_free(codec->audio_name);
codec->audio_name = NULL;
if (payload_type != PTYPE_UNDEFINED)
codec->payload_type = payload_type;
if (!audio_name) {
switch (payload_type) {
case 3: audio_name = "GSM/8000/1"; break;
case 8: audio_name = "PCMA/8000/1"; break;
case 18: audio_name = "G729/8000/1"; break;
default:
/* Payload type is unknown, don't change rate and
* channels. */
/* TODO: return value? */
return 0;
}
}
if (sscanf(audio_name, "%63[^/]/%d/%d",
audio_codec, &rate, &channels) < 1)
return -EINVAL;
codec->rate = rate;
codec->channels = channels;
codec->subtype_name = talloc_strdup(ctx, audio_codec);
codec->audio_name = talloc_strdup(ctx, audio_name);
if (!strcmp(audio_codec, "G729")) {
codec->frame_duration_num = 10;
codec->frame_duration_den = 1000;
} else {
codec->frame_duration_num = DEFAULT_RTP_AUDIO_FRAME_DUR_NUM;
codec->frame_duration_den = DEFAULT_RTP_AUDIO_FRAME_DUR_DEN;
}
if (payload_type < 0) {
payload_type = 96;
if (rate == 8000 && channels == 1) {
if (!strcmp(audio_codec, "GSM"))
payload_type = 3;
else if (!strcmp(audio_codec, "PCMA"))
payload_type = 8;
else if (!strcmp(audio_codec, "G729"))
payload_type = 18;
}
codec->payload_type = payload_type;
}
if (channels != 1)
LOGP(DMGCP, LOGL_NOTICE,
"Channels != 1 in SDP: '%s'\n", audio_name);
return 0;
}
int mgcp_parse_sdp_data(struct mgcp_rtp_end *rtp, struct mgcp_parse_data *p)
{
char *line;
int found_media = 0;
/* TODO/XXX make it more generic */
int audio_payload = -1;
int audio_payload_alt = -1;
for_each_line(line, p->save) {
switch (line[0]) {
case 'o':
case 's':
case 't':
case 'v':
/* skip these SDP attributes */
break;
case 'a': {
int payload;
int ptime, ptime2 = 0;
char audio_name[64];
if (audio_payload == -1)
break;
if (sscanf(line, "a=rtpmap:%d %63s",
&payload, audio_name) == 2) {
if (payload == audio_payload)
mgcp_set_audio_info(p->cfg, &rtp->codec,
payload, audio_name);
else if (payload == audio_payload_alt)
mgcp_set_audio_info(p->cfg, &rtp->alt_codec,
payload, audio_name);
} else if (sscanf(line, "a=ptime:%d-%d",
&ptime, &ptime2) >= 1) {
if (ptime2 > 0 && ptime2 != ptime)
rtp->packet_duration_ms = 0;
else
rtp->packet_duration_ms = ptime;
} else if (sscanf(line, "a=maxptime:%d", &ptime2) == 1) {
/* TODO/XXX: Store this per codec and derive it on use */
if (ptime2 * rtp->codec.frame_duration_den >
rtp->codec.frame_duration_num * 1500)
/* more than 1 frame */
rtp->packet_duration_ms = 0;
}
break;
}
case 'm': {
int port, rc;
audio_payload = -1;
audio_payload_alt = -1;
rc = sscanf(line, "m=audio %d RTP/AVP %d %d",
&port, &audio_payload, &audio_payload_alt);
if (rc >= 2) {
rtp->rtp_port = htons(port);
rtp->rtcp_port = htons(port + 1);
found_media = 1;
mgcp_set_audio_info(p->cfg, &rtp->codec, audio_payload, NULL);
if (rc == 3)
mgcp_set_audio_info(p->cfg, &rtp->alt_codec,
audio_payload_alt, NULL);
}
break;
}
case 'c': {
char ipv4[16];
if (sscanf(line, "c=IN IP4 %15s", ipv4) == 1) {
inet_aton(ipv4, &rtp->addr);
}
break;
}
default:
if (p->endp)
LOGP(DMGCP, LOGL_NOTICE,
"Unhandled SDP option: '%c'/%d on 0x%x\n",
line[0], line[0], ENDPOINT_NUMBER(p->endp));
else
LOGP(DMGCP, LOGL_NOTICE,
"Unhandled SDP option: '%c'/%d\n",
line[0], line[0]);
break;
}
}
if (found_media)
LOGP(DMGCP, LOGL_NOTICE,
"Got media info via SDP: port %d, payload %d (%s), "
"duration %d, addr %s\n",
ntohs(rtp->rtp_port), rtp->codec.payload_type,
rtp->codec.subtype_name ? rtp->codec.subtype_name : "unknown",
rtp->packet_duration_ms, inet_ntoa(rtp->addr));
return found_media;
}
|
