libavformat/sapenc.c

   1 /*
   2  * Session Announcement Protocol (RFC 2974) muxer
   3  * Copyright (c) 2010 Martin Storsjo
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #include "avformat.h"
  23 #include "libavutil/mem.h"
  24 #include "libavutil/parseutils.h"
  25 #include "libavutil/random_seed.h"
  26 #include "libavutil/avstring.h"
  27 #include "libavutil/dict.h"
  28 #include "libavutil/intreadwrite.h"
  29 #include "libavutil/time.h"
  30 #include "internal.h"
  31 #include "mux.h"
  32 #include "network.h"
  33 #include "os_support.h"
  34 #include "rtpenc_chain.h"
  35 #include "url.h"
  36
  37 struct SAPState {
  38     uint8_t    *ann;
  39     int         ann_size;
  40     URLContext *ann_fd;
  41     int64_t     last_time;
  42 };
  43
  44 static int sap_write_close(AVFormatContext *s)
  45 {
  46     struct SAPState *sap = s->priv_data;
  47     int i;
  48
  49     for (i = 0; i < s->nb_streams; i++) {
  50         AVFormatContext *rtpctx = s->streams[i]->priv_data;
  51         if (!rtpctx)
  52             continue;
  53         av_write_trailer(rtpctx);
  54         avio_closep(&rtpctx->pb);
  55         avformat_free_context(rtpctx);
  56         s->streams[i]->priv_data = NULL;
  57     }
  58
  59     if (sap->last_time && sap->ann && sap->ann_fd) {
  60         sap->ann[0] |= 4; /* Session deletion*/
  61         ffurl_write(sap->ann_fd, sap->ann, sap->ann_size);
  62     }
  63
  64     av_freep(&sap->ann);
  65     ffurl_closep(&sap->ann_fd);
  66     ff_network_close();
  67     return 0;
  68 }
  69
  70 static int sap_write_header(AVFormatContext *s)
  71 {
  72     struct SAPState *sap = s->priv_data;
  73     char host[1024], path[1024], url[1024], announce_addr[50] = "";
  74     char *option_list;
  75     int port = 9875, base_port = 5004, i, pos = 0, same_port = 0, ttl = 255;
  76     AVFormatContext **contexts = NULL;
  77     int ret = 0;
  78     struct sockaddr_storage localaddr;
  79     socklen_t addrlen = sizeof(localaddr);
  80     int udp_fd;
  81     AVDictionaryEntry* title = av_dict_get(s->metadata, "title", NULL, 0);
  82
  83     if (!ff_network_init())
  84         return AVERROR(EIO);
  85
  86     /* extract hostname and port */
  87     av_url_split(NULL, 0, NULL, 0, host, sizeof(host), &base_port,
  88                  path, sizeof(path), s->url);
  89     if (base_port < 0)
  90         base_port = 5004;
  91
  92     /* search for options */
  93     option_list = strrchr(path, '?');
  94     if (option_list) {
  95         char buf[50];
  96         if (av_find_info_tag(buf, sizeof(buf), "announce_port", option_list)) {
  97             port = strtol(buf, NULL, 10);
  98         }
  99         if (av_find_info_tag(buf, sizeof(buf), "same_port", option_list)) {
 100             same_port = strtol(buf, NULL, 10);
 101         }
 102         if (av_find_info_tag(buf, sizeof(buf), "ttl", option_list)) {
 103             ttl = strtol(buf, NULL, 10);
 104         }
 105         if (av_find_info_tag(buf, sizeof(buf), "announce_addr", option_list)) {
 106             av_strlcpy(announce_addr, buf, sizeof(announce_addr));
 107         }
 108     }
 109
 110     if (!announce_addr[0]) {
 111         struct addrinfo hints = { 0 }, *ai = NULL;
 112         hints.ai_family = AF_UNSPEC;
 113         if (getaddrinfo(host, NULL, &hints, &ai)) {
 114             av_log(s, AV_LOG_ERROR, "Unable to resolve %s\n", host);
 115             ret = AVERROR(EIO);
 116             goto fail;
 117         }
 118         if (ai->ai_family == AF_INET) {
 119             /* Also known as sap.mcast.net */
 120             av_strlcpy(announce_addr, "224.2.127.254", sizeof(announce_addr));
 121 #if HAVE_STRUCT_SOCKADDR_IN6
 122         } else if (ai->ai_family == AF_INET6) {
 123             /* With IPv6, you can use the same destination in many different
 124              * multicast subnets, to choose how far you want it routed.
 125              * This one is intended to be routed globally. */
 126             av_strlcpy(announce_addr, "ff0e::2:7ffe", sizeof(announce_addr));
 127 #endif
 128         } else {
 129             freeaddrinfo(ai);
 130             av_log(s, AV_LOG_ERROR, "Host %s resolved to unsupported "
 131                                     "address family\n", host);
 132             ret = AVERROR(EIO);
 133             goto fail;
 134         }
 135         freeaddrinfo(ai);
 136     }
 137
 138     contexts = av_calloc(s->nb_streams, sizeof(*contexts));
 139     if (!contexts) {
 140         ret = AVERROR(ENOMEM);
 141         goto fail;
 142     }
 143
 144     if (s->start_time_realtime == 0  ||  s->start_time_realtime == AV_NOPTS_VALUE)
 145         s->start_time_realtime = av_gettime();
 146     for (i = 0; i < s->nb_streams; i++) {
 147         URLContext *fd;
 148         char *new_url;
 149
 150         ff_url_join(url, sizeof(url), "rtp", NULL, host, base_port,
 151                     "?ttl=%d", ttl);
 152         if (!same_port)
 153             base_port += 2;
 154         ret = ffurl_open_whitelist(&fd, url, AVIO_FLAG_WRITE,
 155                                    &s->interrupt_callback, NULL,
 156                                    s->protocol_whitelist, s->protocol_blacklist, NULL);
 157         if (ret) {
 158             ret = AVERROR(EIO);
 159             goto fail;
 160         }
 161         ret = ff_rtp_chain_mux_open(&contexts[i], s, s->streams[i], fd, 0, i);
 162         if (ret < 0)
 163             goto fail;
 164         s->streams[i]->priv_data = contexts[i];
 165         s->streams[i]->time_base = contexts[i]->streams[0]->time_base;
 166         new_url = av_strdup(url);
 167         if (!new_url) {
 168             ret = AVERROR(ENOMEM);
 169             goto fail;
 170         }
 171         ff_format_set_url(contexts[i], new_url);
 172     }
 173
 174     if (s->nb_streams > 0 && title)
 175         av_dict_set(&contexts[0]->metadata, "title", title->value, 0);
 176
 177     ff_url_join(url, sizeof(url), "udp", NULL, announce_addr, port,
 178                 "?ttl=%d&connect=1", ttl);
 179     ret = ffurl_open_whitelist(&sap->ann_fd, url, AVIO_FLAG_WRITE,
 180                                &s->interrupt_callback, NULL,
 181                                s->protocol_whitelist, s->protocol_blacklist, NULL);
 182     if (ret) {
 183         ret = AVERROR(EIO);
 184         goto fail;
 185     }
 186
 187     udp_fd = ffurl_get_file_handle(sap->ann_fd);
 188     if (getsockname(udp_fd, (struct sockaddr*) &localaddr, &addrlen)) {
 189         ret = AVERROR(EIO);
 190         goto fail;
 191     }
 192     if (localaddr.ss_family != AF_INET
 193 #if HAVE_STRUCT_SOCKADDR_IN6
 194         && localaddr.ss_family != AF_INET6
 195 #endif
 196         ) {
 197         av_log(s, AV_LOG_ERROR, "Unsupported protocol family\n");
 198         ret = AVERROR(EIO);
 199         goto fail;
 200     }
 201     sap->ann_size = 8192;
 202     sap->ann = av_mallocz(sap->ann_size);
 203     if (!sap->ann) {
 204         ret = AVERROR(EIO);
 205         goto fail;
 206     }
 207     sap->ann[pos] = (1 << 5);
 208 #if HAVE_STRUCT_SOCKADDR_IN6
 209     if (localaddr.ss_family == AF_INET6)
 210         sap->ann[pos] |= 0x10;
 211 #endif
 212     pos++;
 213     sap->ann[pos++] = 0; /* Authentication length */
 214     AV_WB16(&sap->ann[pos], av_get_random_seed());
 215     pos += 2;
 216     if (localaddr.ss_family == AF_INET) {
 217         memcpy(&sap->ann[pos], &((struct sockaddr_in*)&localaddr)->sin_addr,
 218                sizeof(struct in_addr));
 219         pos += sizeof(struct in_addr);
 220 #if HAVE_STRUCT_SOCKADDR_IN6
 221     } else {
 222         memcpy(&sap->ann[pos], &((struct sockaddr_in6*)&localaddr)->sin6_addr,
 223                sizeof(struct in6_addr));
 224         pos += sizeof(struct in6_addr);
 225 #endif
 226     }
 227
 228     av_strlcpy(&sap->ann[pos], "application/sdp", sap->ann_size - pos);
 229     pos += strlen(&sap->ann[pos]) + 1;
 230
 231     if (av_sdp_create(contexts, s->nb_streams, &sap->ann[pos],
 232                       sap->ann_size - pos)) {
 233         ret = AVERROR_INVALIDDATA;
 234         goto fail;
 235     }
 236     av_freep(&contexts);
 237     av_log(s, AV_LOG_VERBOSE, "SDP:\n%s\n", &sap->ann[pos]);
 238     pos += strlen(&sap->ann[pos]);
 239     sap->ann_size = pos;
 240
 241     if (sap->ann_size > sap->ann_fd->max_packet_size) {
 242         av_log(s, AV_LOG_ERROR, "Announcement too large to send in one "
 243                                 "packet\n");
 244         goto fail;
 245     }
 246
 247     return 0;
 248
 249 fail:
 250     av_free(contexts);
 251     sap_write_close(s);
 252     return ret;
 253 }
 254
 255 static int sap_write_packet(AVFormatContext *s, AVPacket *pkt)
 256 {
 257     AVFormatContext *rtpctx;
 258     struct SAPState *sap = s->priv_data;
 259     int64_t now = av_gettime_relative();
 260
 261     if (!sap->last_time || now - sap->last_time > 5000000) {
 262         int ret = ffurl_write(sap->ann_fd, sap->ann, sap->ann_size);
 263         /* Don't abort even if we get "Destination unreachable" */
 264         if (ret < 0 && ret != AVERROR(ECONNREFUSED))
 265             return ret;
 266         sap->last_time = now;
 267     }
 268     rtpctx = s->streams[pkt->stream_index]->priv_data;
 269     return ff_write_chained(rtpctx, 0, pkt, s, 0);
 270 }
 271
 272 const FFOutputFormat ff_sap_muxer = {
 273     .p.name            = "sap",
 274     .p.long_name       = NULL_IF_CONFIG_SMALL("SAP output"),
 275     .priv_data_size    = sizeof(struct SAPState),
 276     .p.audio_codec     = AV_CODEC_ID_AAC,
 277     .p.video_codec     = AV_CODEC_ID_MPEG4,
 278     .write_header      = sap_write_header,
 279     .write_packet      = sap_write_packet,
 280     .write_trailer     = sap_write_close,
 281     .p.flags           = AVFMT_NOFILE | AVFMT_GLOBALHEADER,
 282 };