/* * Session Announcement Protocol (RFC 2974) muxer * Copyright (c) 2010 Martin Storsjo * * This file is part of Libav. * * Libav is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * Libav 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 * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include "avformat.h" #include "libavutil/parseutils.h" #include "libavutil/random_seed.h" #include "libavutil/avstring.h" #include "libavutil/intreadwrite.h" #include "internal.h" #include "network.h" #include "os_support.h" #include "rtpenc_chain.h" #include "url.h" struct SAPState { uint8_t *ann; int ann_size; URLContext *ann_fd; int64_t last_time; }; static int sap_write_close(AVFormatContext *s) { struct SAPState *sap = s->priv_data; int i; for (i = 0; i < s->nb_streams; i++) { AVFormatContext *rtpctx = s->streams[i]->priv_data; if (!rtpctx) continue; av_write_trailer(rtpctx); avio_close(rtpctx->pb); avformat_free_context(rtpctx); s->streams[i]->priv_data = NULL; } if (sap->last_time && sap->ann && sap->ann_fd) { sap->ann[0] |= 4; /* Session deletion*/ ffurl_write(sap->ann_fd, sap->ann, sap->ann_size); } av_freep(&sap->ann); if (sap->ann_fd) ffurl_close(sap->ann_fd); ff_network_close(); return 0; } static int sap_write_header(AVFormatContext *s) { struct SAPState *sap = s->priv_data; char host[1024], path[1024], url[1024], announce_addr[50] = ""; char *option_list; int port = 9875, base_port = 5004, i, pos = 0, same_port = 0, ttl = 255; AVFormatContext **contexts = NULL; int ret = 0; struct sockaddr_storage localaddr; socklen_t addrlen = sizeof(localaddr); int udp_fd; if (!ff_network_init()) return AVERROR(EIO); /* extract hostname and port */ av_url_split(NULL, 0, NULL, 0, host, sizeof(host), &base_port, path, sizeof(path), s->filename); if (base_port < 0) base_port = 5004; /* search for options */ option_list = strrchr(path, '?'); if (option_list) { char buf[50]; if (av_find_info_tag(buf, sizeof(buf), "announce_port", option_list)) { port = strtol(buf, NULL, 10); } if (av_find_info_tag(buf, sizeof(buf), "same_port", option_list)) { same_port = strtol(buf, NULL, 10); } if (av_find_info_tag(buf, sizeof(buf), "ttl", option_list)) { ttl = strtol(buf, NULL, 10); } if (av_find_info_tag(buf, sizeof(buf), "announce_addr", option_list)) { av_strlcpy(announce_addr, buf, sizeof(announce_addr)); } } if (!announce_addr[0]) { struct addrinfo hints, *ai = NULL; memset(&hints, 0, sizeof(hints)); hints.ai_family = AF_UNSPEC; if (getaddrinfo(host, NULL, &hints, &ai)) { av_log(s, AV_LOG_ERROR, "Unable to resolve %s\n", host); ret = AVERROR(EIO); goto fail; } if (ai->ai_family == AF_INET) { /* Also known as sap.mcast.net */ av_strlcpy(announce_addr, "224.2.127.254", sizeof(announce_addr)); #if HAVE_STRUCT_SOCKADDR_IN6 } else if (ai->ai_family == AF_INET6) { /* With IPv6, you can use the same destination in many different * multicast subnets, to choose how far you want it routed. * This one is intended to be routed globally. */ av_strlcpy(announce_addr, "ff0e::2:7ffe", sizeof(announce_addr)); #endif } else { freeaddrinfo(ai); av_log(s, AV_LOG_ERROR, "Host %s resolved to unsupported " "address family\n", host); ret = AVERROR(EIO); goto fail; } freeaddrinfo(ai); } contexts = av_mallocz(sizeof(AVFormatContext*) * s->nb_streams); if (!contexts) { ret = AVERROR(ENOMEM); goto fail; } s->start_time_realtime = av_gettime(); for (i = 0; i < s->nb_streams; i++) { URLContext *fd; ff_url_join(url, sizeof(url), "rtp", NULL, host, base_port, "?ttl=%d", ttl); if (!same_port) base_port += 2; ret = ffurl_open(&fd, url, AVIO_FLAG_WRITE); if (ret) { ret = AVERROR(EIO); goto fail; } s->streams[i]->priv_data = contexts[i] = ff_rtp_chain_mux_open(s, s->streams[i], fd, 0); av_strlcpy(contexts[i]->filename, url, sizeof(contexts[i]->filename)); } ff_url_join(url, sizeof(url), "udp", NULL, announce_addr, port, "?ttl=%d&connect=1", ttl); ret = ffurl_open(&sap->ann_fd, url, AVIO_FLAG_WRITE); if (ret) { ret = AVERROR(EIO); goto fail; } udp_fd = ffurl_get_file_handle(sap->ann_fd); if (getsockname(udp_fd, (struct sockaddr*) &localaddr, &addrlen)) { ret = AVERROR(EIO); goto fail; } if (localaddr.ss_family != AF_INET #if HAVE_STRUCT_SOCKADDR_IN6 && localaddr.ss_family != AF_INET6 #endif ) { av_log(s, AV_LOG_ERROR, "Unsupported protocol family\n"); ret = AVERROR(EIO); goto fail; } sap->ann_size = 8192; sap->ann = av_mallocz(sap->ann_size); if (!sap->ann) { ret = AVERROR(EIO); goto fail; } sap->ann[pos] = (1 << 5); #if HAVE_STRUCT_SOCKADDR_IN6 if (localaddr.ss_family == AF_INET6) sap->ann[pos] |= 0x10; #endif pos++; sap->ann[pos++] = 0; /* Authentication length */ AV_WB16(&sap->ann[pos], av_get_random_seed()); pos += 2; if (localaddr.ss_family == AF_INET) { memcpy(&sap->ann[pos], &((struct sockaddr_in*)&localaddr)->sin_addr, sizeof(struct in_addr)); pos += sizeof(struct in_addr); #if HAVE_STRUCT_SOCKADDR_IN6 } else { memcpy(&sap->ann[pos], &((struct sockaddr_in6*)&localaddr)->sin6_addr, sizeof(struct in6_addr)); pos += sizeof(struct in6_addr); #endif } av_strlcpy(&sap->ann[pos], "application/sdp", sap->ann_size - pos); pos += strlen(&sap->ann[pos]) + 1; if (av_sdp_create(contexts, s->nb_streams, &sap->ann[pos], sap->ann_size - pos)) { ret = AVERROR_INVALIDDATA; goto fail; } av_freep(&contexts); av_log(s, AV_LOG_VERBOSE, "SDP:\n%s\n", &sap->ann[pos]); pos += strlen(&sap->ann[pos]); sap->ann_size = pos; if (sap->ann_size > sap->ann_fd->max_packet_size) { av_log(s, AV_LOG_ERROR, "Announcement too large to send in one " "packet\n"); goto fail; } return 0; fail: av_free(contexts); sap_write_close(s); return ret; } static int sap_write_packet(AVFormatContext *s, AVPacket *pkt) { AVFormatContext *rtpctx; struct SAPState *sap = s->priv_data; int64_t now = av_gettime(); if (!sap->last_time || now - sap->last_time > 5000000) { int ret = ffurl_write(sap->ann_fd, sap->ann, sap->ann_size); /* Don't abort even if we get "Destination unreachable" */ if (ret < 0 && ret != AVERROR(ECONNREFUSED)) return ret; sap->last_time = now; } rtpctx = s->streams[pkt->stream_index]->priv_data; return ff_write_chained(rtpctx, 0, pkt, s); } AVOutputFormat ff_sap_muxer = { .name = "sap", .long_name = NULL_IF_CONFIG_SMALL("SAP output format"), .priv_data_size = sizeof(struct SAPState), .audio_codec = CODEC_ID_AAC, .video_codec = CODEC_ID_MPEG4, .write_header = sap_write_header, .write_packet = sap_write_packet, .write_trailer = sap_write_close, .flags = AVFMT_NOFILE | AVFMT_GLOBALHEADER, };