code.delx.au - pulseaudio/blob - src/modules/rtp/sdp.c

   1 /***
   2   This file is part of PulseAudio.
   3
   4   Copyright 2006 Lennart Poettering
   5
   6   PulseAudio is free software; you can redistribute it and/or modify
   7   it under the terms of the GNU Lesser General Public License as published
   8   by the Free Software Foundation; either version 2 of the License,
   9   or (at your option) any later version.
  10
  11   PulseAudio is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public License
  17   along with PulseAudio; if not, write to the Free Software
  18   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  19   USA.
  20 ***/
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include <config.h>
  24 #endif
  25
  26 #include <time.h>
  27 #include <stdlib.h>
  28 #include <sys/types.h>
  29 #include <sys/socket.h>
  30 #include <netinet/in.h>
  31 #include <arpa/inet.h>
  32 #include <string.h>
  33
  34 #include <pulse/xmalloc.h>
  35 #include <pulse/util.h>
  36
  37 #include <pulsecore/core-util.h>
  38 #include <pulsecore/log.h>
  39 #include <pulsecore/macro.h>
  40
  41 #include "sdp.h"
  42 #include "rtp.h"
  43
  44 char *pa_sdp_build(int af, const void *src, const void *dst, const char *name, uint16_t port, uint8_t payload, const pa_sample_spec *ss) {
  45     uint32_t ntp;
  46     char buf_src[64], buf_dst[64], un[64];
  47     const char *u, *f, *a;
  48
  49     pa_assert(src);
  50     pa_assert(dst);
  51     pa_assert(af == AF_INET || af == AF_INET6);
  52
  53     pa_assert_se(f = pa_rtp_format_to_string(ss->format));
  54
  55     if (!(u = pa_get_user_name(un, sizeof(un))))
  56         u = "-";
  57
  58     ntp = (uint32_t) time(NULL) + 2208988800U;
  59
  60     pa_assert_se(a = inet_ntop(af, src, buf_src, sizeof(buf_src)));
  61     pa_assert_se(a = inet_ntop(af, dst, buf_dst, sizeof(buf_dst)));
  62
  63     return pa_sprintf_malloc(
  64             PA_SDP_HEADER
  65             "o=%s %lu 0 IN %s %s\n"
  66             "s=%s\n"
  67             "c=IN %s %s\n"
  68             "t=%lu 0\n"
  69             "a=recvonly\n"
  70             "m=audio %u RTP/AVP %i\n"
  71             "a=rtpmap:%i %s/%u/%u\n"
  72             "a=type:broadcast\n",
  73             u, (unsigned long) ntp, af == AF_INET ? "IP4" : "IP6", buf_src,
  74             name,
  75             af == AF_INET ? "IP4" : "IP6", buf_dst,
  76             (unsigned long) ntp,
  77             port, payload,
  78             payload, f, ss->rate, ss->channels);
  79 }
  80
  81 static pa_sample_spec *parse_sdp_sample_spec(pa_sample_spec *ss, char *c) {
  82     unsigned rate, channels;
  83     pa_assert(ss);
  84     pa_assert(c);
  85
  86     if (pa_startswith(c, "L16/")) {
  87         ss->format = PA_SAMPLE_S16BE;
  88         c += 4;
  89     } else if (pa_startswith(c, "L8/")) {
  90         ss->format = PA_SAMPLE_U8;
  91         c += 3;
  92     } else if (pa_startswith(c, "PCMA/")) {
  93         ss->format = PA_SAMPLE_ALAW;
  94         c += 5;
  95     } else if (pa_startswith(c, "PCMU/")) {
  96         ss->format = PA_SAMPLE_ULAW;
  97         c += 5;
  98     } else
  99         return NULL;
 100
 101     if (sscanf(c, "%u/%u", &rate, &channels) == 2) {
 102         ss->rate = (uint32_t) rate;
 103         ss->channels = (uint8_t) channels;
 104     } else if (sscanf(c, "%u", &rate) == 2) {
 105         ss->rate = (uint32_t) rate;
 106         ss->channels = 1;
 107     } else
 108         return NULL;
 109
 110     if (!pa_sample_spec_valid(ss))
 111         return NULL;
 112
 113     return ss;
 114 }
 115
 116 pa_sdp_info *pa_sdp_parse(const char *t, pa_sdp_info *i, int is_goodbye) {
 117     uint16_t port = 0;
 118     pa_bool_t ss_valid = FALSE;
 119
 120     pa_assert(t);
 121     pa_assert(i);
 122
 123     i->origin = i->session_name = NULL;
 124     i->salen = 0;
 125     i->payload = 255;
 126
 127     if (!pa_startswith(t, PA_SDP_HEADER)) {
 128         pa_log("Failed to parse SDP data: invalid header.");
 129         goto fail;
 130     }
 131
 132     t += sizeof(PA_SDP_HEADER)-1;
 133
 134     while (*t) {
 135         size_t l;
 136
 137         l = strcspn(t, "\n");
 138
 139         if (l <= 2) {
 140             pa_log("Failed to parse SDP data: line too short: >%s<.", t);
 141             goto fail;
 142         }
 143
 144         if (pa_startswith(t, "o="))
 145             i->origin = pa_xstrndup(t+2, l-2);
 146         else if (pa_startswith(t, "s="))
 147             i->session_name = pa_xstrndup(t+2, l-2);
 148         else if (pa_startswith(t, "c=IN IP4 ")) {
 149             char a[64];
 150             size_t k;
 151
 152             k = l-8 > sizeof(a) ? sizeof(a) : l-8;
 153
 154             pa_strlcpy(a, t+9, k);
 155             a[strcspn(a, "/")] = 0;
 156
 157             if (inet_pton(AF_INET, a, &((struct sockaddr_in*) &i->sa)->sin_addr) <= 0) {
 158                 pa_log("Failed to parse SDP data: bad address: >%s<.", a);
 159                 goto fail;
 160             }
 161
 162             ((struct sockaddr_in*) &i->sa)->sin_family = AF_INET;
 163             ((struct sockaddr_in*) &i->sa)->sin_port = 0;
 164             i->salen = sizeof(struct sockaddr_in);
 165         } else if (pa_startswith(t, "c=IN IP6 ")) {
 166             char a[64];
 167             size_t k;
 168
 169             k = l-8 > sizeof(a) ? sizeof(a) : l-8;
 170
 171             pa_strlcpy(a, t+9, k);
 172             a[strcspn(a, "/")] = 0;
 173
 174             if (inet_pton(AF_INET6, a, &((struct sockaddr_in6*) &i->sa)->sin6_addr) <= 0) {
 175                 pa_log("Failed to parse SDP data: bad address: >%s<.", a);
 176                 goto fail;
 177             }
 178
 179             ((struct sockaddr_in6*) &i->sa)->sin6_family = AF_INET6;
 180             ((struct sockaddr_in6*) &i->sa)->sin6_port = 0;
 181             i->salen = sizeof(struct sockaddr_in6);
 182         } else if (pa_startswith(t, "m=audio ")) {
 183
 184             if (i->payload > 127) {
 185                 int _port, _payload;
 186
 187                 if (sscanf(t+8, "%i RTP/AVP %i", &_port, &_payload) == 2) {
 188
 189                     if (_port <= 0 || _port > 0xFFFF) {
 190                         pa_log("Failed to parse SDP data: invalid port %i.", _port);
 191                         goto fail;
 192                     }
 193
 194                     if (_payload < 0 || _payload > 127) {
 195                         pa_log("Failed to parse SDP data: invalid payload %i.", _payload);
 196                         goto fail;
 197                     }
 198
 199                     port = (uint16_t) _port;
 200                     i->payload = (uint8_t) _payload;
 201
 202                     if (pa_rtp_sample_spec_from_payload(i->payload, &i->sample_spec))
 203                         ss_valid = TRUE;
 204                 }
 205             }
 206         } else if (pa_startswith(t, "a=rtpmap:")) {
 207
 208             if (i->payload <= 127) {
 209                 char c[64];
 210                 int _payload;
 211
 212                 if (sscanf(t+9, "%i %64c", &_payload, c) == 2) {
 213
 214                     if (_payload < 0 || _payload > 127) {
 215                         pa_log("Failed to parse SDP data: invalid payload %i.", _payload);
 216                         goto fail;
 217                     }
 218                     if (_payload == i->payload) {
 219
 220                         c[strcspn(c, "\n")] = 0;
 221
 222                         if (parse_sdp_sample_spec(&i->sample_spec, c))
 223                             ss_valid = TRUE;
 224                     }
 225                 }
 226             }
 227         }
 228
 229         t += l;
 230
 231         if (*t == '\n')
 232             t++;
 233     }
 234
 235     if (!i->origin || (!is_goodbye && (!i->salen || i->payload > 127 || !ss_valid || port == 0))) {
 236         pa_log("Failed to parse SDP data: missing data.");
 237         goto fail;
 238     }
 239
 240     if (((struct sockaddr*) &i->sa)->sa_family == AF_INET)
 241         ((struct sockaddr_in*) &i->sa)->sin_port = htons(port);
 242     else
 243         ((struct sockaddr_in6*) &i->sa)->sin6_port = htons(port);
 244
 245     return i;
 246
 247 fail:
 248     pa_xfree(i->origin);
 249     pa_xfree(i->session_name);
 250
 251     return NULL;
 252 }
 253
 254 void pa_sdp_info_destroy(pa_sdp_info *i) {
 255     pa_assert(i);
 256
 257     pa_xfree(i->origin);
 258     pa_xfree(i->session_name);
 259 }