/* * RTP network protocol * Copyright (c) 2002 Fabrice Bellard * * This file is part of FFmpeg. * * FFmpeg 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. * * FFmpeg 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 FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** * @file * RTP protocol */ #include "libavutil/parseutils.h" #include "libavutil/avstring.h" #include "libavutil/opt.h" #include "avformat.h" #include "avio_internal.h" #include "rtp.h" #include "rtpproto.h" #include "url.h" #include <stdarg.h> #include "internal.h" #include "network.h" #include "os_support.h" #include <fcntl.h> #if HAVE_POLL_H #include <sys/poll.h> #endif typedef struct RTPContext { const AVClass *class; URLContext *rtp_hd, *rtcp_hd; int rtp_fd, rtcp_fd, nb_ssm_include_addrs, nb_ssm_exclude_addrs; struct sockaddr_storage **ssm_include_addrs, **ssm_exclude_addrs; int write_to_source; struct sockaddr_storage last_rtp_source, last_rtcp_source; socklen_t last_rtp_source_len, last_rtcp_source_len; int ttl; int buffer_size; int rtcp_port, local_rtpport, local_rtcpport; int connect; int pkt_size; int dscp; char *sources; char *block; } RTPContext; #define OFFSET(x) offsetof(RTPContext, x) #define D AV_OPT_FLAG_DECODING_PARAM #define E AV_OPT_FLAG_ENCODING_PARAM static const AVOption options[] = { { "ttl", "Time to live (in milliseconds, multicast only)", OFFSET(ttl), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, INT_MAX, .flags = D|E }, { "buffer_size", "Send/Receive buffer size (in bytes)", OFFSET(buffer_size), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, INT_MAX, .flags = D|E }, { "rtcp_port", "Custom rtcp port", OFFSET(rtcp_port), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, INT_MAX, .flags = D|E }, { "local_rtpport", "Local rtp port", OFFSET(local_rtpport), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, INT_MAX, .flags = D|E }, { "local_rtcpport", "Local rtcp port", OFFSET(local_rtcpport), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, INT_MAX, .flags = D|E }, { "connect", "Connect socket", OFFSET(connect), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, .flags = D|E }, { "write_to_source", "Send packets to the source address of the latest received packet", OFFSET(write_to_source), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, .flags = D|E }, { "pkt_size", "Maximum packet size", OFFSET(pkt_size), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, INT_MAX, .flags = D|E }, { "dscp", "DSCP class", OFFSET(dscp), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, INT_MAX, .flags = D|E }, { "sources", "Source list", OFFSET(sources), AV_OPT_TYPE_STRING, { .str = NULL }, .flags = D|E }, { "block", "Block list", OFFSET(block), AV_OPT_TYPE_STRING, { .str = NULL }, .flags = D|E }, { NULL } }; static const AVClass rtp_class = { .class_name = "rtp", .item_name = av_default_item_name, .option = options, .version = LIBAVUTIL_VERSION_INT, }; /** * If no filename is given to av_open_input_file because you want to * get the local port first, then you must call this function to set * the remote server address. * * @param h media file context * @param uri of the remote server * @return zero if no error. */ int ff_rtp_set_remote_url(URLContext *h, const char *uri) { RTPContext *s = h->priv_data; char hostname[256]; int port, rtcp_port; const char *p; char buf[1024]; char path[1024]; av_url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &port, path, sizeof(path), uri); rtcp_port = port + 1; p = strchr(uri, '?'); if (p) { if (av_find_info_tag(buf, sizeof(buf), "rtcpport", p)) { rtcp_port = strtol(buf, NULL, 10); } } ff_url_join(buf, sizeof(buf), "udp", NULL, hostname, port, "%s", path); ff_udp_set_remote_url(s->rtp_hd, buf); ff_url_join(buf, sizeof(buf), "udp", NULL, hostname, rtcp_port, "%s", path); ff_udp_set_remote_url(s->rtcp_hd, buf); return 0; } static struct addrinfo* rtp_resolve_host(const char *hostname, int port, int type, int family, int flags) { struct addrinfo hints = { 0 }, *res = 0; int error; char service[16]; snprintf(service, sizeof(service), "%d", port); hints.ai_socktype = type; hints.ai_family = family; hints.ai_flags = flags; if ((error = getaddrinfo(hostname, service, &hints, &res))) { res = NULL; av_log(NULL, AV_LOG_ERROR, "rtp_resolve_host: %s\n", gai_strerror(error)); } return res; } static int compare_addr(const struct sockaddr_storage *a, const struct sockaddr_storage *b) { if (a->ss_family != b->ss_family) return 1; if (a->ss_family == AF_INET) { return (((const struct sockaddr_in *)a)->sin_addr.s_addr != ((const struct sockaddr_in *)b)->sin_addr.s_addr); } #if HAVE_STRUCT_SOCKADDR_IN6 if (a->ss_family == AF_INET6) { const uint8_t *s6_addr_a = ((const struct sockaddr_in6 *)a)->sin6_addr.s6_addr; const uint8_t *s6_addr_b = ((const struct sockaddr_in6 *)b)->sin6_addr.s6_addr; return memcmp(s6_addr_a, s6_addr_b, 16); } #endif return 1; } static int get_port(const struct sockaddr_storage *ss) { if (ss->ss_family == AF_INET) return ntohs(((const struct sockaddr_in *)ss)->sin_port); #if HAVE_STRUCT_SOCKADDR_IN6 if (ss->ss_family == AF_INET6) return ntohs(((const struct sockaddr_in6 *)ss)->sin6_port); #endif return 0; } static void set_port(struct sockaddr_storage *ss, int port) { if (ss->ss_family == AF_INET) ((struct sockaddr_in *)ss)->sin_port = htons(port); #if HAVE_STRUCT_SOCKADDR_IN6 else if (ss->ss_family == AF_INET6) ((struct sockaddr_in6 *)ss)->sin6_port = htons(port); #endif } static int rtp_check_source_lists(RTPContext *s, struct sockaddr_storage *source_addr_ptr) { int i; if (s->nb_ssm_exclude_addrs) { for (i = 0; i < s->nb_ssm_exclude_addrs; i++) { if (!compare_addr(source_addr_ptr, s->ssm_exclude_addrs[i])) return 1; } } if (s->nb_ssm_include_addrs) { for (i = 0; i < s->nb_ssm_include_addrs; i++) { if (!compare_addr(source_addr_ptr, s->ssm_include_addrs[i])) return 0; } return 1; } return 0; } /** * add option to url of the form: * "http://host:port/path?option1=val1&option2=val2... */ static av_printf_format(3, 4) void url_add_option(char *buf, int buf_size, const char *fmt, ...) { char buf1[1024]; va_list ap; va_start(ap, fmt); if (strchr(buf, '?')) av_strlcat(buf, "&", buf_size); else av_strlcat(buf, "?", buf_size); vsnprintf(buf1, sizeof(buf1), fmt, ap); av_strlcat(buf, buf1, buf_size); va_end(ap); } static void build_udp_url(RTPContext *s, char *buf, int buf_size, const char *hostname, int port, int local_port, const char *include_sources, const char *exclude_sources) { ff_url_join(buf, buf_size, "udp", NULL, hostname, port, NULL); if (local_port >= 0) url_add_option(buf, buf_size, "localport=%d", local_port); if (s->ttl >= 0) url_add_option(buf, buf_size, "ttl=%d", s->ttl); if (s->buffer_size >= 0) url_add_option(buf, buf_size, "buffer_size=%d", s->buffer_size); if (s->pkt_size >= 0) url_add_option(buf, buf_size, "pkt_size=%d", s->pkt_size); if (s->connect) url_add_option(buf, buf_size, "connect=1"); if (s->dscp >= 0) url_add_option(buf, buf_size, "dscp=%d", s->dscp); url_add_option(buf, buf_size, "fifo_size=0"); if (include_sources && include_sources[0]) url_add_option(buf, buf_size, "sources=%s", include_sources); if (exclude_sources && exclude_sources[0]) url_add_option(buf, buf_size, "block=%s", exclude_sources); } static void rtp_parse_addr_list(URLContext *h, char *buf, struct sockaddr_storage ***address_list_ptr, int *address_list_size_ptr) { struct addrinfo *ai = NULL; struct sockaddr_storage *source_addr; char tmp = '\0', *p = buf, *next; /* Resolve all of the IPs */ while (p && p[0]) { next = strchr(p, ','); if (next) { tmp = *next; *next = '\0'; } ai = rtp_resolve_host(p, 0, SOCK_DGRAM, AF_UNSPEC, 0); if (ai) { source_addr = av_mallocz(sizeof(struct sockaddr_storage)); if (!source_addr) { freeaddrinfo(ai); break; } memcpy(source_addr, ai->ai_addr, ai->ai_addrlen); freeaddrinfo(ai); dynarray_add(address_list_ptr, address_list_size_ptr, source_addr); } else { av_log(h, AV_LOG_WARNING, "Unable to resolve %s\n", p); } if (next) { *next = tmp; p = next + 1; } else { p = NULL; } } } /** * url syntax: rtp://host:port[?option=val...] * option: 'ttl=n' : set the ttl value (for multicast only) * 'rtcpport=n' : set the remote rtcp port to n * 'localrtpport=n' : set the local rtp port to n * 'localrtcpport=n' : set the local rtcp port to n * 'pkt_size=n' : set max packet size * 'connect=0/1' : do a connect() on the UDP socket * 'sources=ip[,ip]' : list allowed source IP addresses * 'block=ip[,ip]' : list disallowed source IP addresses * 'write_to_source=0/1' : send packets to the source address of the latest received packet * 'dscp=n' : set DSCP value to n (QoS) * deprecated option: * 'localport=n' : set the local port to n * * if rtcpport isn't set the rtcp port will be the rtp port + 1 * if local rtp port isn't set any available port will be used for the local * rtp and rtcp ports * if the local rtcp port is not set it will be the local rtp port + 1 */ static int rtp_open(URLContext *h, const char *uri, int flags) { RTPContext *s = h->priv_data; int rtp_port; char hostname[256], include_sources[1024] = "", exclude_sources[1024] = ""; char *sources = include_sources, *block = exclude_sources; char buf[1024]; char path[1024]; const char *p; int i, max_retry_count = 3; av_url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &rtp_port, path, sizeof(path), uri); /* extract parameters */ if (s->rtcp_port < 0) s->rtcp_port = rtp_port + 1; p = strchr(uri, '?'); if (p) { if (av_find_info_tag(buf, sizeof(buf), "ttl", p)) { s->ttl = strtol(buf, NULL, 10); } if (av_find_info_tag(buf, sizeof(buf), "rtcpport", p)) { s->rtcp_port = strtol(buf, NULL, 10); } if (av_find_info_tag(buf, sizeof(buf), "localport", p)) { s->local_rtpport = strtol(buf, NULL, 10); } if (av_find_info_tag(buf, sizeof(buf), "localrtpport", p)) { s->local_rtpport = strtol(buf, NULL, 10); } if (av_find_info_tag(buf, sizeof(buf), "localrtcpport", p)) { s->local_rtcpport = strtol(buf, NULL, 10); } if (av_find_info_tag(buf, sizeof(buf), "pkt_size", p)) { s->pkt_size = strtol(buf, NULL, 10); } if (av_find_info_tag(buf, sizeof(buf), "connect", p)) { s->connect = strtol(buf, NULL, 10); } if (av_find_info_tag(buf, sizeof(buf), "write_to_source", p)) { s->write_to_source = strtol(buf, NULL, 10); } if (av_find_info_tag(buf, sizeof(buf), "dscp", p)) { s->dscp = strtol(buf, NULL, 10); } if (av_find_info_tag(buf, sizeof(buf), "sources", p)) { av_strlcpy(include_sources, buf, sizeof(include_sources)); rtp_parse_addr_list(h, buf, &s->ssm_include_addrs, &s->nb_ssm_include_addrs); } else { rtp_parse_addr_list(h, s->sources, &s->ssm_include_addrs, &s->nb_ssm_include_addrs); sources = s->sources; } if (av_find_info_tag(buf, sizeof(buf), "block", p)) { av_strlcpy(exclude_sources, buf, sizeof(exclude_sources)); rtp_parse_addr_list(h, buf, &s->ssm_exclude_addrs, &s->nb_ssm_exclude_addrs); } else { rtp_parse_addr_list(h, s->block, &s->ssm_exclude_addrs, &s->nb_ssm_exclude_addrs); block = s->block; } } for (i = 0; i < max_retry_count; i++) { build_udp_url(s, buf, sizeof(buf), hostname, rtp_port, s->local_rtpport, sources, block); if (ffurl_open(&s->rtp_hd, buf, flags, &h->interrupt_callback, NULL) < 0) goto fail; s->local_rtpport = ff_udp_get_local_port(s->rtp_hd); if(s->local_rtpport == 65535) { s->local_rtpport = -1; continue; } if (s->local_rtcpport < 0) { s->local_rtcpport = s->local_rtpport + 1; build_udp_url(s, buf, sizeof(buf), hostname, s->rtcp_port, s->local_rtcpport, sources, block); if (ffurl_open(&s->rtcp_hd, buf, flags, &h->interrupt_callback, NULL) < 0) { s->local_rtpport = s->local_rtcpport = -1; continue; } break; } build_udp_url(s, buf, sizeof(buf), hostname, s->rtcp_port, s->local_rtcpport, sources, block); if (ffurl_open(&s->rtcp_hd, buf, flags, &h->interrupt_callback, NULL) < 0) goto fail; break; } /* just to ease handle access. XXX: need to suppress direct handle access */ s->rtp_fd = ffurl_get_file_handle(s->rtp_hd); s->rtcp_fd = ffurl_get_file_handle(s->rtcp_hd); h->max_packet_size = s->rtp_hd->max_packet_size; h->is_streamed = 1; return 0; fail: if (s->rtp_hd) ffurl_close(s->rtp_hd); if (s->rtcp_hd) ffurl_close(s->rtcp_hd); return AVERROR(EIO); } static int rtp_read(URLContext *h, uint8_t *buf, int size) { RTPContext *s = h->priv_data; int len, n, i; struct pollfd p[2] = {{s->rtp_fd, POLLIN, 0}, {s->rtcp_fd, POLLIN, 0}}; int poll_delay = h->flags & AVIO_FLAG_NONBLOCK ? 0 : 100; struct sockaddr_storage *addrs[2] = { &s->last_rtp_source, &s->last_rtcp_source }; socklen_t *addr_lens[2] = { &s->last_rtp_source_len, &s->last_rtcp_source_len }; for(;;) { if (ff_check_interrupt(&h->interrupt_callback)) return AVERROR_EXIT; n = poll(p, 2, poll_delay); if (n > 0) { /* first try RTCP, then RTP */ for (i = 1; i >= 0; i--) { if (!(p[i].revents & POLLIN)) continue; *addr_lens[i] = sizeof(*addrs[i]); len = recvfrom(p[i].fd, buf, size, 0, (struct sockaddr *)addrs[i], addr_lens[i]); if (len < 0) { if (ff_neterrno() == AVERROR(EAGAIN) || ff_neterrno() == AVERROR(EINTR)) continue; return AVERROR(EIO); } if (rtp_check_source_lists(s, addrs[i])) continue; return len; } } else if (n < 0) { if (ff_neterrno() == AVERROR(EINTR)) continue; return AVERROR(EIO); } if (h->flags & AVIO_FLAG_NONBLOCK) return AVERROR(EAGAIN); } return len; } static int rtp_write(URLContext *h, const uint8_t *buf, int size) { RTPContext *s = h->priv_data; int ret; URLContext *hd; if (size < 2) return AVERROR(EINVAL); if ((buf[0] & 0xc0) != (RTP_VERSION << 6)) av_log(h, AV_LOG_WARNING, "Data doesn't look like RTP packets, " "make sure the RTP muxer is used\n"); if (s->write_to_source) { int fd; struct sockaddr_storage *source, temp_source; socklen_t *source_len, temp_len; if (!s->last_rtp_source.ss_family && !s->last_rtcp_source.ss_family) { av_log(h, AV_LOG_ERROR, "Unable to send packet to source, no packets received yet\n"); // Intentionally not returning an error here return size; } if (RTP_PT_IS_RTCP(buf[1])) { fd = s->rtcp_fd; source = &s->last_rtcp_source; source_len = &s->last_rtcp_source_len; } else { fd = s->rtp_fd; source = &s->last_rtp_source; source_len = &s->last_rtp_source_len; } if (!source->ss_family) { source = &temp_source; source_len = &temp_len; if (RTP_PT_IS_RTCP(buf[1])) { temp_source = s->last_rtp_source; temp_len = s->last_rtp_source_len; set_port(source, get_port(source) + 1); av_log(h, AV_LOG_INFO, "Not received any RTCP packets yet, inferring peer port " "from the RTP port\n"); } else { temp_source = s->last_rtcp_source; temp_len = s->last_rtcp_source_len; set_port(source, get_port(source) - 1); av_log(h, AV_LOG_INFO, "Not received any RTP packets yet, inferring peer port " "from the RTCP port\n"); } } if (!(h->flags & AVIO_FLAG_NONBLOCK)) { ret = ff_network_wait_fd(fd, 1); if (ret < 0) return ret; } ret = sendto(fd, buf, size, 0, (struct sockaddr *) source, *source_len); return ret < 0 ? ff_neterrno() : ret; } if (RTP_PT_IS_RTCP(buf[1])) { /* RTCP payload type */ hd = s->rtcp_hd; } else { /* RTP payload type */ hd = s->rtp_hd; } ret = ffurl_write(hd, buf, size); return ret; } static int rtp_close(URLContext *h) { RTPContext *s = h->priv_data; int i; for (i = 0; i < s->nb_ssm_include_addrs; i++) av_freep(&s->ssm_include_addrs[i]); av_freep(&s->ssm_include_addrs); for (i = 0; i < s->nb_ssm_exclude_addrs; i++) av_freep(&s->ssm_exclude_addrs[i]); av_freep(&s->ssm_exclude_addrs); ffurl_close(s->rtp_hd); ffurl_close(s->rtcp_hd); return 0; } /** * Return the local rtp port used by the RTP connection * @param h media file context * @return the local port number */ int ff_rtp_get_local_rtp_port(URLContext *h) { RTPContext *s = h->priv_data; return ff_udp_get_local_port(s->rtp_hd); } /** * Return the local rtcp port used by the RTP connection * @param h media file context * @return the local port number */ int ff_rtp_get_local_rtcp_port(URLContext *h) { RTPContext *s = h->priv_data; return ff_udp_get_local_port(s->rtcp_hd); } static int rtp_get_file_handle(URLContext *h) { RTPContext *s = h->priv_data; return s->rtp_fd; } static int rtp_get_multi_file_handle(URLContext *h, int **handles, int *numhandles) { RTPContext *s = h->priv_data; int *hs = *handles = av_malloc(sizeof(**handles) * 2); if (!hs) return AVERROR(ENOMEM); hs[0] = s->rtp_fd; hs[1] = s->rtcp_fd; *numhandles = 2; return 0; } URLProtocol ff_rtp_protocol = { .name = "rtp", .url_open = rtp_open, .url_read = rtp_read, .url_write = rtp_write, .url_close = rtp_close, .url_get_file_handle = rtp_get_file_handle, .url_get_multi_file_handle = rtp_get_multi_file_handle, .priv_data_size = sizeof(RTPContext), .flags = URL_PROTOCOL_FLAG_NETWORK, .priv_data_class = &rtp_class, };