/* * UDP prototype streaming system * Copyright (c) 2000, 2001, 2002 Fabrice Bellard * * 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 */ /** * @file * UDP protocol */ #define _BSD_SOURCE /* Needed for using struct ip_mreq with recent glibc */ #include "avformat.h" #include "avio_internal.h" #include "libavutil/parseutils.h" #include "libavutil/avstring.h" #include <unistd.h> #include "internal.h" #include "network.h" #include "os_support.h" #include "url.h" #include <sys/time.h> #ifndef IPV6_ADD_MEMBERSHIP #define IPV6_ADD_MEMBERSHIP IPV6_JOIN_GROUP #define IPV6_DROP_MEMBERSHIP IPV6_LEAVE_GROUP #endif typedef struct { int udp_fd; int ttl; int buffer_size; int is_multicast; int local_port; int reuse_socket; struct sockaddr_storage dest_addr; int dest_addr_len; int is_connected; } UDPContext; #define UDP_TX_BUF_SIZE 32768 #define UDP_MAX_PKT_SIZE 65536 static int udp_set_multicast_ttl(int sockfd, int mcastTTL, struct sockaddr *addr) { #ifdef IP_MULTICAST_TTL if (addr->sa_family == AF_INET) { if (setsockopt(sockfd, IPPROTO_IP, IP_MULTICAST_TTL, &mcastTTL, sizeof(mcastTTL)) < 0) { av_log(NULL, AV_LOG_ERROR, "setsockopt(IP_MULTICAST_TTL): %s\n", strerror(errno)); return -1; } } #endif #if defined(IPPROTO_IPV6) && defined(IPV6_MULTICAST_HOPS) if (addr->sa_family == AF_INET6) { if (setsockopt(sockfd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &mcastTTL, sizeof(mcastTTL)) < 0) { av_log(NULL, AV_LOG_ERROR, "setsockopt(IPV6_MULTICAST_HOPS): %s\n", strerror(errno)); return -1; } } #endif return 0; } static int udp_join_multicast_group(int sockfd, struct sockaddr *addr) { #ifdef IP_ADD_MEMBERSHIP if (addr->sa_family == AF_INET) { struct ip_mreq mreq; mreq.imr_multiaddr.s_addr = ((struct sockaddr_in *)addr)->sin_addr.s_addr; mreq.imr_interface.s_addr= INADDR_ANY; if (setsockopt(sockfd, IPPROTO_IP, IP_ADD_MEMBERSHIP, (const void *)&mreq, sizeof(mreq)) < 0) { av_log(NULL, AV_LOG_ERROR, "setsockopt(IP_ADD_MEMBERSHIP): %s\n", strerror(errno)); return -1; } } #endif #if HAVE_STRUCT_IPV6_MREQ && defined(IPPROTO_IPV6) if (addr->sa_family == AF_INET6) { struct ipv6_mreq mreq6; memcpy(&mreq6.ipv6mr_multiaddr, &(((struct sockaddr_in6 *)addr)->sin6_addr), sizeof(struct in6_addr)); mreq6.ipv6mr_interface= 0; if (setsockopt(sockfd, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, &mreq6, sizeof(mreq6)) < 0) { av_log(NULL, AV_LOG_ERROR, "setsockopt(IPV6_ADD_MEMBERSHIP): %s\n", strerror(errno)); return -1; } } #endif return 0; } static int udp_leave_multicast_group(int sockfd, struct sockaddr *addr) { #ifdef IP_DROP_MEMBERSHIP if (addr->sa_family == AF_INET) { struct ip_mreq mreq; mreq.imr_multiaddr.s_addr = ((struct sockaddr_in *)addr)->sin_addr.s_addr; mreq.imr_interface.s_addr= INADDR_ANY; if (setsockopt(sockfd, IPPROTO_IP, IP_DROP_MEMBERSHIP, (const void *)&mreq, sizeof(mreq)) < 0) { av_log(NULL, AV_LOG_ERROR, "setsockopt(IP_DROP_MEMBERSHIP): %s\n", strerror(errno)); return -1; } } #endif #if HAVE_STRUCT_IPV6_MREQ && defined(IPPROTO_IPV6) if (addr->sa_family == AF_INET6) { struct ipv6_mreq mreq6; memcpy(&mreq6.ipv6mr_multiaddr, &(((struct sockaddr_in6 *)addr)->sin6_addr), sizeof(struct in6_addr)); mreq6.ipv6mr_interface= 0; if (setsockopt(sockfd, IPPROTO_IPV6, IPV6_DROP_MEMBERSHIP, &mreq6, sizeof(mreq6)) < 0) { av_log(NULL, AV_LOG_ERROR, "setsockopt(IPV6_DROP_MEMBERSHIP): %s\n", strerror(errno)); return -1; } } #endif return 0; } static struct addrinfo* udp_resolve_host(const char *hostname, int port, int type, int family, int flags) { struct addrinfo hints = { 0 }, *res = 0; int error; char sport[16]; const char *node = 0, *service = "0"; if (port > 0) { snprintf(sport, sizeof(sport), "%d", port); service = sport; } if ((hostname) && (hostname[0] != '\0') && (hostname[0] != '?')) { node = hostname; } hints.ai_socktype = type; hints.ai_family = family; hints.ai_flags = flags; if ((error = getaddrinfo(node, service, &hints, &res))) { res = NULL; av_log(NULL, AV_LOG_ERROR, "udp_resolve_host: %s\n", gai_strerror(error)); } return res; } static int udp_set_url(struct sockaddr_storage *addr, const char *hostname, int port) { struct addrinfo *res0; int addr_len; res0 = udp_resolve_host(hostname, port, SOCK_DGRAM, AF_UNSPEC, 0); if (res0 == 0) return AVERROR(EIO); memcpy(addr, res0->ai_addr, res0->ai_addrlen); addr_len = res0->ai_addrlen; freeaddrinfo(res0); return addr_len; } static int udp_socket_create(UDPContext *s, struct sockaddr_storage *addr, int *addr_len, const char *localaddr) { int udp_fd = -1; struct addrinfo *res0 = NULL, *res = NULL; int family = AF_UNSPEC; if (((struct sockaddr *) &s->dest_addr)->sa_family) family = ((struct sockaddr *) &s->dest_addr)->sa_family; res0 = udp_resolve_host(localaddr[0] ? localaddr : NULL, s->local_port, SOCK_DGRAM, family, AI_PASSIVE); if (res0 == 0) goto fail; for (res = res0; res; res=res->ai_next) { udp_fd = socket(res->ai_family, SOCK_DGRAM, 0); if (udp_fd > 0) break; av_log(NULL, AV_LOG_ERROR, "socket: %s\n", strerror(errno)); } if (udp_fd < 0) goto fail; memcpy(addr, res->ai_addr, res->ai_addrlen); *addr_len = res->ai_addrlen; freeaddrinfo(res0); return udp_fd; fail: if (udp_fd >= 0) closesocket(udp_fd); if(res0) freeaddrinfo(res0); return -1; } static int udp_port(struct sockaddr_storage *addr, int addr_len) { char sbuf[sizeof(int)*3+1]; if (getnameinfo((struct sockaddr *)addr, addr_len, NULL, 0, sbuf, sizeof(sbuf), NI_NUMERICSERV) != 0) { av_log(NULL, AV_LOG_ERROR, "getnameinfo: %s\n", strerror(errno)); return -1; } return strtol(sbuf, NULL, 10); } /** * 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. * * url syntax: udp://host:port[?option=val...] * option: 'ttl=n' : set the ttl value (for multicast only) * 'localport=n' : set the local port * 'pkt_size=n' : set max packet size * 'reuse=1' : enable reusing the socket * * @param h media file context * @param uri of the remote server * @return zero if no error. */ int ff_udp_set_remote_url(URLContext *h, const char *uri) { UDPContext *s = h->priv_data; char hostname[256], buf[10]; int port; const char *p; av_url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &port, NULL, 0, uri); /* set the destination address */ s->dest_addr_len = udp_set_url(&s->dest_addr, hostname, port); if (s->dest_addr_len < 0) { return AVERROR(EIO); } s->is_multicast = ff_is_multicast_address((struct sockaddr*) &s->dest_addr); p = strchr(uri, '?'); if (p) { if (av_find_info_tag(buf, sizeof(buf), "connect", p)) { int was_connected = s->is_connected; s->is_connected = strtol(buf, NULL, 10); if (s->is_connected && !was_connected) { if (connect(s->udp_fd, (struct sockaddr *) &s->dest_addr, s->dest_addr_len)) { s->is_connected = 0; av_log(h, AV_LOG_ERROR, "connect: %s\n", strerror(errno)); return AVERROR(EIO); } } } } return 0; } /** * Return the local port used by the UDP connection * @param h media file context * @return the local port number */ int ff_udp_get_local_port(URLContext *h) { UDPContext *s = h->priv_data; return s->local_port; } /** * Return the udp file handle for select() usage to wait for several RTP * streams at the same time. * @param h media file context */ static int udp_get_file_handle(URLContext *h) { UDPContext *s = h->priv_data; return s->udp_fd; } /* put it in UDP context */ /* return non zero if error */ static int udp_open(URLContext *h, const char *uri, int flags) { char hostname[1024], localaddr[1024] = ""; int port, udp_fd = -1, tmp, bind_ret = -1; UDPContext *s = h->priv_data; int is_output; const char *p; char buf[256]; struct sockaddr_storage my_addr; int len; int reuse_specified = 0; h->is_streamed = 1; h->max_packet_size = 1472; is_output = !(flags & AVIO_FLAG_READ); s->ttl = 16; s->buffer_size = is_output ? UDP_TX_BUF_SIZE : UDP_MAX_PKT_SIZE; p = strchr(uri, '?'); if (p) { if (av_find_info_tag(buf, sizeof(buf), "reuse", p)) { char *endptr = NULL; s->reuse_socket = strtol(buf, &endptr, 10); /* assume if no digits were found it is a request to enable it */ if (buf == endptr) s->reuse_socket = 1; reuse_specified = 1; } if (av_find_info_tag(buf, sizeof(buf), "ttl", p)) { s->ttl = strtol(buf, NULL, 10); } if (av_find_info_tag(buf, sizeof(buf), "localport", p)) { s->local_port = strtol(buf, NULL, 10); } if (av_find_info_tag(buf, sizeof(buf), "pkt_size", p)) { h->max_packet_size = strtol(buf, NULL, 10); } if (av_find_info_tag(buf, sizeof(buf), "buffer_size", p)) { s->buffer_size = strtol(buf, NULL, 10); } if (av_find_info_tag(buf, sizeof(buf), "connect", p)) { s->is_connected = strtol(buf, NULL, 10); } if (av_find_info_tag(buf, sizeof(buf), "localaddr", p)) { av_strlcpy(localaddr, buf, sizeof(localaddr)); } } /* fill the dest addr */ av_url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &port, NULL, 0, uri); /* XXX: fix av_url_split */ if (hostname[0] == '\0' || hostname[0] == '?') { /* only accepts null hostname if input */ if (!(flags & AVIO_FLAG_READ)) goto fail; } else { if (ff_udp_set_remote_url(h, uri) < 0) goto fail; } if ((s->is_multicast || !s->local_port) && (h->flags & AVIO_FLAG_READ)) s->local_port = port; udp_fd = udp_socket_create(s, &my_addr, &len, localaddr); if (udp_fd < 0) goto fail; /* Follow the requested reuse option, unless it's multicast in which * case enable reuse unless explicitly disabled. */ if (s->reuse_socket || (s->is_multicast && !reuse_specified)) { s->reuse_socket = 1; if (setsockopt (udp_fd, SOL_SOCKET, SO_REUSEADDR, &(s->reuse_socket), sizeof(s->reuse_socket)) != 0) goto fail; } /* If multicast, try binding the multicast address first, to avoid * receiving UDP packets from other sources aimed at the same UDP * port. This fails on windows. This makes sending to the same address * using sendto() fail, so only do it if we're opened in read-only mode. */ if (s->is_multicast && !(h->flags & AVIO_FLAG_WRITE)) { bind_ret = bind(udp_fd,(struct sockaddr *)&s->dest_addr, len); } /* bind to the local address if not multicast or if the multicast * bind failed */ /* the bind is needed to give a port to the socket now */ if (bind_ret < 0 && bind(udp_fd,(struct sockaddr *)&my_addr, len) < 0) { av_log(h, AV_LOG_ERROR, "bind failed: %s\n", strerror(errno)); goto fail; } len = sizeof(my_addr); getsockname(udp_fd, (struct sockaddr *)&my_addr, &len); s->local_port = udp_port(&my_addr, len); if (s->is_multicast) { if (h->flags & AVIO_FLAG_WRITE) { /* output */ if (udp_set_multicast_ttl(udp_fd, s->ttl, (struct sockaddr *)&s->dest_addr) < 0) goto fail; } if (h->flags & AVIO_FLAG_READ) { /* input */ if (udp_join_multicast_group(udp_fd, (struct sockaddr *)&s->dest_addr) < 0) goto fail; } } if (is_output) { /* limit the tx buf size to limit latency */ tmp = s->buffer_size; if (setsockopt(udp_fd, SOL_SOCKET, SO_SNDBUF, &tmp, sizeof(tmp)) < 0) { av_log(h, AV_LOG_ERROR, "setsockopt(SO_SNDBUF): %s\n", strerror(errno)); goto fail; } } else { /* set udp recv buffer size to the largest possible udp packet size to * avoid losing data on OSes that set this too low by default. */ tmp = s->buffer_size; if (setsockopt(udp_fd, SOL_SOCKET, SO_RCVBUF, &tmp, sizeof(tmp)) < 0) { av_log(h, AV_LOG_WARNING, "setsockopt(SO_RECVBUF): %s\n", strerror(errno)); } /* make the socket non-blocking */ ff_socket_nonblock(udp_fd, 1); } if (s->is_connected) { if (connect(udp_fd, (struct sockaddr *) &s->dest_addr, s->dest_addr_len)) { av_log(h, AV_LOG_ERROR, "connect: %s\n", strerror(errno)); goto fail; } } s->udp_fd = udp_fd; return 0; fail: if (udp_fd >= 0) closesocket(udp_fd); return AVERROR(EIO); } static int udp_read(URLContext *h, uint8_t *buf, int size) { UDPContext *s = h->priv_data; int ret; if (!(h->flags & AVIO_FLAG_NONBLOCK)) { ret = ff_network_wait_fd(s->udp_fd, 0); if (ret < 0) return ret; } ret = recv(s->udp_fd, buf, size, 0); return ret < 0 ? ff_neterrno() : ret; } static int udp_write(URLContext *h, const uint8_t *buf, int size) { UDPContext *s = h->priv_data; int ret; if (!(h->flags & AVIO_FLAG_NONBLOCK)) { ret = ff_network_wait_fd(s->udp_fd, 1); if (ret < 0) return ret; } if (!s->is_connected) { ret = sendto (s->udp_fd, buf, size, 0, (struct sockaddr *) &s->dest_addr, s->dest_addr_len); } else ret = send(s->udp_fd, buf, size, 0); return ret < 0 ? ff_neterrno() : ret; } static int udp_close(URLContext *h) { UDPContext *s = h->priv_data; if (s->is_multicast && (h->flags & AVIO_FLAG_READ)) udp_leave_multicast_group(s->udp_fd, (struct sockaddr *)&s->dest_addr); closesocket(s->udp_fd); return 0; } URLProtocol ff_udp_protocol = { .name = "udp", .url_open = udp_open, .url_read = udp_read, .url_write = udp_write, .url_close = udp_close, .url_get_file_handle = udp_get_file_handle, .priv_data_size = sizeof(UDPContext), .flags = URL_PROTOCOL_FLAG_NETWORK, };