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 2.1 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 <string.h>
  32
  33 #include <pulse/xmalloc.h>
  34 #include <pulse/util.h>
  35
  36 #include <pulsecore/core-util.h>
  37 #include <pulsecore/log.h>
  38 #include <pulsecore/macro.h>
  39 #include <pulsecore/arpa-inet.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;
  48
  49     pa_assert(src);
  50     pa_assert(dst);
  51
  52 #ifdef HAVE_IPV6
  53     pa_assert(af == AF_INET || af == AF_INET6);
  54 #else
  55     pa_assert(af == AF_INET);
  56 #endif
  57
  58     pa_assert_se(f = pa_rtp_format_to_string(ss->format));
  59
  60     if (!(u = pa_get_user_name(un, sizeof(un))))
  61         u = "-";
  62
  63     ntp = (uint32_t) time(NULL) + 2208988800U;
  64
  65     pa_assert_se(inet_ntop(af, src, buf_src, sizeof(buf_src)));
  66     pa_assert_se(inet_ntop(af, dst, buf_dst, sizeof(buf_dst)));
  67
  68     return pa_sprintf_malloc(
  69             PA_SDP_HEADER
  70             "o=%s %lu 0 IN %s %s\n"
  71             "s=%s\n"
  72             "c=IN %s %s\n"
  73             "t=%lu 0\n"
  74             "a=recvonly\n"
  75             "m=audio %u RTP/AVP %i\n"
  76             "a=rtpmap:%i %s/%u/%u\n"
  77             "a=type:broadcast\n",
  78             u, (unsigned long) ntp, af == AF_INET ? "IP4" : "IP6", buf_src,
  79             name,
  80             af == AF_INET ? "IP4" : "IP6", buf_dst,
  81             (unsigned long) ntp,
  82             port, payload,
  83             payload, f, ss->rate, ss->channels);
  84 }
  85
  86 static pa_sample_spec *parse_sdp_sample_spec(pa_sample_spec *ss, char *c) {
  87     unsigned rate, channels;
  88     pa_assert(ss);
  89     pa_assert(c);
  90
  91     if (pa_startswith(c, "L16/")) {
  92         ss->format = PA_SAMPLE_S16BE;
  93         c += 4;
  94     } else if (pa_startswith(c, "L8/")) {
  95         ss->format = PA_SAMPLE_U8;
  96         c += 3;
  97     } else if (pa_startswith(c, "PCMA/")) {
  98         ss->format = PA_SAMPLE_ALAW;
  99         c += 5;
 100     } else if (pa_startswith(c, "PCMU/")) {
 101         ss->format = PA_SAMPLE_ULAW;
 102         c += 5;
 103     } else
 104         return NULL;
 105
 106     if (sscanf(c, "%u/%u", &rate, &channels) == 2) {
 107         ss->rate = (uint32_t) rate;
 108         ss->channels = (uint8_t) channels;
 109     } else if (sscanf(c, "%u", &rate) == 2) {
 110         ss->rate = (uint32_t) rate;
 111         ss->channels = 1;
 112     } else
 113         return NULL;
 114
 115     if (!pa_sample_spec_valid(ss))
 116         return NULL;
 117
 118     return ss;
 119 }
 120
 121 pa_sdp_info *pa_sdp_parse(const char *t, pa_sdp_info *i, int is_goodbye) {
 122     uint16_t port = 0;
 123     bool ss_valid = false;
 124
 125     pa_assert(t);
 126     pa_assert(i);
 127
 128     i->origin = i->session_name = NULL;
 129     i->salen = 0;
 130     i->payload = 255;
 131
 132     if (!pa_startswith(t, PA_SDP_HEADER)) {
 133         pa_log("Failed to parse SDP data: invalid header.");
 134         goto fail;
 135     }
 136
 137     t += sizeof(PA_SDP_HEADER)-1;
 138
 139     while (*t) {
 140         size_t l;
 141
 142         l = strcspn(t, "\n");
 143
 144         if (l <= 2) {
 145             pa_log("Failed to parse SDP data: line too short: >%s<.", t);
 146             goto fail;
 147         }
 148
 149         if (pa_startswith(t, "o="))
 150             i->origin = pa_xstrndup(t+2, l-2);
 151         else if (pa_startswith(t, "s="))
 152             i->session_name = pa_xstrndup(t+2, l-2);
 153         else if (pa_startswith(t, "c=IN IP4 ")) {
 154             char a[64];
 155             size_t k;
 156
 157             k = l-8 > sizeof(a) ? sizeof(a) : l-8;
 158
 159             pa_strlcpy(a, t+9, k);
 160             a[strcspn(a, "/")] = 0;
 161
 162             if (inet_pton(AF_INET, a, &((struct sockaddr_in*) &i->sa)->sin_addr) <= 0) {
 163                 pa_log("Failed to parse SDP data: bad address: >%s<.", a);
 164                 goto fail;
 165             }
 166
 167             ((struct sockaddr_in*) &i->sa)->sin_family = AF_INET;
 168             ((struct sockaddr_in*) &i->sa)->sin_port = 0;
 169             i->salen = sizeof(struct sockaddr_in);
 170 #ifdef HAVE_IPV6
 171         } else if (pa_startswith(t, "c=IN IP6 ")) {
 172             char a[64];
 173             size_t k;
 174
 175             k = l-8 > sizeof(a) ? sizeof(a) : l-8;
 176
 177             pa_strlcpy(a, t+9, k);
 178             a[strcspn(a, "/")] = 0;
 179
 180             if (inet_pton(AF_INET6, a, &((struct sockaddr_in6*) &i->sa)->sin6_addr) <= 0) {
 181                 pa_log("Failed to parse SDP data: bad address: >%s<.", a);
 182                 goto fail;
 183             }
 184
 185             ((struct sockaddr_in6*) &i->sa)->sin6_family = AF_INET6;
 186             ((struct sockaddr_in6*) &i->sa)->sin6_port = 0;
 187             i->salen = sizeof(struct sockaddr_in6);
 188 #endif
 189         } else if (pa_startswith(t, "m=audio ")) {
 190
 191             if (i->payload > 127) {
 192                 int _port, _payload;
 193
 194                 if (sscanf(t+8, "%i RTP/AVP %i", &_port, &_payload) == 2) {
 195
 196                     if (_port <= 0 || _port > 0xFFFF) {
 197                         pa_log("Failed to parse SDP data: invalid port %i.", _port);
 198                         goto fail;
 199                     }
 200
 201                     if (_payload < 0 || _payload > 127) {
 202                         pa_log("Failed to parse SDP data: invalid payload %i.", _payload);
 203                         goto fail;
 204                     }
 205
 206                     port = (uint16_t) _port;
 207                     i->payload = (uint8_t) _payload;
 208
 209                     if (pa_rtp_sample_spec_from_payload(i->payload, &i->sample_spec))
 210                         ss_valid = true;
 211                 }
 212             }
 213         } else if (pa_startswith(t, "a=rtpmap:")) {
 214
 215             if (i->payload <= 127) {
 216                 char c[64];
 217                 int _payload;
 218
 219                 if (sscanf(t+9, "%i %64c", &_payload, c) == 2) {
 220
 221                     if (_payload < 0 || _payload > 127) {
 222                         pa_log("Failed to parse SDP data: invalid payload %i.", _payload);
 223                         goto fail;
 224                     }
 225                     if (_payload == i->payload) {
 226
 227                         c[strcspn(c, "\n")] = 0;
 228
 229                         if (parse_sdp_sample_spec(&i->sample_spec, c))
 230                             ss_valid = true;
 231                     }
 232                 }
 233             }
 234         }
 235
 236         t += l;
 237
 238         if (*t == '\n')
 239             t++;
 240     }
 241
 242     if (!i->origin || (!is_goodbye && (!i->salen || i->payload > 127 || !ss_valid || port == 0))) {
 243         pa_log("Failed to parse SDP data: missing data.");
 244         goto fail;
 245     }
 246
 247     if (((struct sockaddr*) &i->sa)->sa_family == AF_INET)
 248         ((struct sockaddr_in*) &i->sa)->sin_port = htons(port);
 249     else
 250         ((struct sockaddr_in6*) &i->sa)->sin6_port = htons(port);
 251
 252     return i;
 253
 254 fail:
 255     pa_xfree(i->origin);
 256     pa_xfree(i->session_name);
 257
 258     return NULL;
 259 }
 260
 261 void pa_sdp_info_destroy(pa_sdp_info *i) {
 262     pa_assert(i);
 263
 264     pa_xfree(i->origin);
 265     pa_xfree(i->session_name);
 266 }