libavformat/udp.c

   1 /*
   2  * UDP prototype streaming system
   3  * Copyright (c) 2000, 2001, 2002 Fabrice Bellard
   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 /**
  23  * @file libavformat/udp.c
  24  * UDP protocol
  25  */
  26
  27 #define _BSD_SOURCE     /* Needed for using struct ip_mreq with recent glibc */
  28 #include "avformat.h"
  29 #include <unistd.h>
  30 #include "network.h"
  31 #include "os_support.h"
  32 #if HAVE_SYS_SELECT_H
  33 #include <sys/select.h>
  34 #endif
  35 #include <sys/time.h>
  36
  37 #ifndef IPV6_ADD_MEMBERSHIP
  38 #define IPV6_ADD_MEMBERSHIP IPV6_JOIN_GROUP
  39 #define IPV6_DROP_MEMBERSHIP IPV6_LEAVE_GROUP
  40 #endif
  41 #ifndef IN_MULTICAST
  42 #define IN_MULTICAST(a) ((((uint32_t)(a)) & 0xf0000000) == 0xe0000000)
  43 #endif
  44 #ifndef IN6_IS_ADDR_MULTICAST
  45 #define IN6_IS_ADDR_MULTICAST(a) (((uint8_t *) (a))[0] == 0xff)
  46 #endif
  47
  48 typedef struct {
  49     int udp_fd;
  50     int ttl;
  51     int buffer_size;
  52     int is_multicast;
  53     int local_port;
  54     int reuse_socket;
  55 #if !CONFIG_IPV6
  56     struct sockaddr_in dest_addr;
  57 #else
  58     struct sockaddr_storage dest_addr;
  59 #endif
  60     int dest_addr_len;
  61 } UDPContext;
  62
  63 #define UDP_TX_BUF_SIZE 32768
  64 #define UDP_MAX_PKT_SIZE 65536
  65
  66 static int udp_set_multicast_ttl(int sockfd, int mcastTTL, struct sockaddr *addr) {
  67 #ifdef IP_MULTICAST_TTL
  68     if (addr->sa_family == AF_INET) {
  69         if (setsockopt(sockfd, IPPROTO_IP, IP_MULTICAST_TTL, &mcastTTL, sizeof(mcastTTL)) < 0) {
  70             av_log(NULL, AV_LOG_ERROR, "setsockopt(IP_MULTICAST_TTL): %s\n", strerror(errno));
  71             return -1;
  72         }
  73     }
  74 #endif
  75 #if CONFIG_IPV6
  76     if (addr->sa_family == AF_INET6) {
  77         if (setsockopt(sockfd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &mcastTTL, sizeof(mcastTTL)) < 0) {
  78             av_log(NULL, AV_LOG_ERROR, "setsockopt(IPV6_MULTICAST_HOPS): %s\n", strerror(errno));
  79             return -1;
  80         }
  81     }
  82 #endif
  83     return 0;
  84 }
  85
  86 static int udp_join_multicast_group(int sockfd, struct sockaddr *addr) {
  87 #ifdef IP_ADD_MEMBERSHIP
  88     if (addr->sa_family == AF_INET) {
  89         struct ip_mreq mreq;
  90
  91         mreq.imr_multiaddr.s_addr = ((struct sockaddr_in *)addr)->sin_addr.s_addr;
  92         mreq.imr_interface.s_addr= INADDR_ANY;
  93         if (setsockopt(sockfd, IPPROTO_IP, IP_ADD_MEMBERSHIP, (const void *)&mreq, sizeof(mreq)) < 0) {
  94             av_log(NULL, AV_LOG_ERROR, "setsockopt(IP_ADD_MEMBERSHIP): %s\n", strerror(errno));
  95             return -1;
  96         }
  97     }
  98 #endif
  99 #if CONFIG_IPV6
 100     if (addr->sa_family == AF_INET6) {
 101         struct ipv6_mreq mreq6;
 102
 103         memcpy(&mreq6.ipv6mr_multiaddr, &(((struct sockaddr_in6 *)addr)->sin6_addr), sizeof(struct in6_addr));
 104         mreq6.ipv6mr_interface= 0;
 105         if (setsockopt(sockfd, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, &mreq6, sizeof(mreq6)) < 0) {
 106             av_log(NULL, AV_LOG_ERROR, "setsockopt(IPV6_ADD_MEMBERSHIP): %s\n", strerror(errno));
 107             return -1;
 108         }
 109     }
 110 #endif
 111     return 0;
 112 }
 113
 114 static int udp_leave_multicast_group(int sockfd, struct sockaddr *addr) {
 115 #ifdef IP_DROP_MEMBERSHIP
 116     if (addr->sa_family == AF_INET) {
 117         struct ip_mreq mreq;
 118
 119         mreq.imr_multiaddr.s_addr = ((struct sockaddr_in *)addr)->sin_addr.s_addr;
 120         mreq.imr_interface.s_addr= INADDR_ANY;
 121         if (setsockopt(sockfd, IPPROTO_IP, IP_DROP_MEMBERSHIP, (const void *)&mreq, sizeof(mreq)) < 0) {
 122             av_log(NULL, AV_LOG_ERROR, "setsockopt(IP_DROP_MEMBERSHIP): %s\n", strerror(errno));
 123             return -1;
 124         }
 125     }
 126 #endif
 127 #if CONFIG_IPV6
 128     if (addr->sa_family == AF_INET6) {
 129         struct ipv6_mreq mreq6;
 130
 131         memcpy(&mreq6.ipv6mr_multiaddr, &(((struct sockaddr_in6 *)addr)->sin6_addr), sizeof(struct in6_addr));
 132         mreq6.ipv6mr_interface= 0;
 133         if (setsockopt(sockfd, IPPROTO_IPV6, IPV6_DROP_MEMBERSHIP, &mreq6, sizeof(mreq6)) < 0) {
 134             av_log(NULL, AV_LOG_ERROR, "setsockopt(IPV6_DROP_MEMBERSHIP): %s\n", strerror(errno));
 135             return -1;
 136         }
 137     }
 138 #endif
 139     return 0;
 140 }
 141
 142 #if CONFIG_IPV6
 143 static struct addrinfo* udp_ipv6_resolve_host(const char *hostname, int port, int type, int family, int flags) {
 144     struct addrinfo hints, *res = 0;
 145     int error;
 146     char sport[16];
 147     const char *node = 0, *service = "0";
 148
 149     if (port > 0) {
 150         snprintf(sport, sizeof(sport), "%d", port);
 151         service = sport;
 152     }
 153     if ((hostname) && (hostname[0] != '\0') && (hostname[0] != '?')) {
 154         node = hostname;
 155     }
 156     memset(&hints, 0, sizeof(hints));
 157     hints.ai_socktype = type;
 158     hints.ai_family   = family;
 159     hints.ai_flags = flags;
 160     if ((error = getaddrinfo(node, service, &hints, &res))) {
 161         av_log(NULL, AV_LOG_ERROR, "udp_ipv6_resolve_host: %s\n", gai_strerror(error));
 162     }
 163
 164     return res;
 165 }
 166
 167 static int udp_set_url(struct sockaddr_storage *addr, const char *hostname, int port) {
 168     struct addrinfo *res0;
 169     int addr_len;
 170
 171     res0 = udp_ipv6_resolve_host(hostname, port, SOCK_DGRAM, AF_UNSPEC, 0);
 172     if (res0 == 0) return AVERROR(EIO);
 173     memcpy(addr, res0->ai_addr, res0->ai_addrlen);
 174     addr_len = res0->ai_addrlen;
 175     freeaddrinfo(res0);
 176
 177     return addr_len;
 178 }
 179
 180 static int is_multicast_address(struct sockaddr_storage *addr)
 181 {
 182     if (addr->ss_family == AF_INET) {
 183         return IN_MULTICAST(ntohl(((struct sockaddr_in *)addr)->sin_addr.s_addr));
 184     }
 185     if (addr->ss_family == AF_INET6) {
 186         return IN6_IS_ADDR_MULTICAST(&((struct sockaddr_in6 *)addr)->sin6_addr);
 187     }
 188
 189     return 0;
 190 }
 191
 192 static int udp_socket_create(UDPContext *s, struct sockaddr_storage *addr, int *addr_len)
 193 {
 194     int udp_fd = -1;
 195     struct addrinfo *res0 = NULL, *res = NULL;
 196     int family = AF_UNSPEC;
 197
 198     if (((struct sockaddr *) &s->dest_addr)->sa_family)
 199         family = ((struct sockaddr *) &s->dest_addr)->sa_family;
 200     res0 = udp_ipv6_resolve_host(0, s->local_port, SOCK_DGRAM, family, AI_PASSIVE);
 201     if (res0 == 0)
 202         goto fail;
 203     for (res = res0; res; res=res->ai_next) {
 204         udp_fd = socket(res->ai_family, SOCK_DGRAM, 0);
 205         if (udp_fd > 0) break;
 206         av_log(NULL, AV_LOG_ERROR, "socket: %s\n", strerror(errno));
 207     }
 208
 209     if (udp_fd < 0)
 210         goto fail;
 211
 212     memcpy(addr, res->ai_addr, res->ai_addrlen);
 213     *addr_len = res->ai_addrlen;
 214
 215     freeaddrinfo(res0);
 216
 217     return udp_fd;
 218
 219  fail:
 220     if (udp_fd >= 0)
 221         closesocket(udp_fd);
 222     if(res0)
 223         freeaddrinfo(res0);
 224     return -1;
 225 }
 226
 227 static int udp_port(struct sockaddr_storage *addr, int addr_len)
 228 {
 229     char sbuf[sizeof(int)*3+1];
 230
 231     if (getnameinfo((struct sockaddr *)addr, addr_len, NULL, 0,  sbuf, sizeof(sbuf), NI_NUMERICSERV) != 0) {
 232         av_log(NULL, AV_LOG_ERROR, "getnameinfo: %s\n", strerror(errno));
 233         return -1;
 234     }
 235
 236     return strtol(sbuf, NULL, 10);
 237 }
 238
 239 #else
 240
 241 static int udp_set_url(struct sockaddr_in *addr, const char *hostname, int port)
 242 {
 243     /* set the destination address */
 244     if (resolve_host(&addr->sin_addr, hostname) < 0)
 245         return AVERROR(EIO);
 246     addr->sin_family = AF_INET;
 247     addr->sin_port = htons(port);
 248
 249     return sizeof(struct sockaddr_in);
 250 }
 251
 252 static int is_multicast_address(struct sockaddr_in *addr)
 253 {
 254     return IN_MULTICAST(ntohl(addr->sin_addr.s_addr));
 255 }
 256
 257 static int udp_socket_create(UDPContext *s, struct sockaddr_in *addr, int *addr_len)
 258 {
 259     int fd;
 260
 261     fd = socket(AF_INET, SOCK_DGRAM, 0);
 262     if (fd < 0)
 263         return -1;
 264
 265     addr->sin_family = AF_INET;
 266     addr->sin_addr.s_addr = htonl (INADDR_ANY);
 267     addr->sin_port = htons(s->local_port);
 268     *addr_len = sizeof(struct sockaddr_in);
 269
 270     return fd;
 271 }
 272
 273 static int udp_port(struct sockaddr_in *addr, int len)
 274 {
 275     return ntohs(addr->sin_port);
 276 }
 277 #endif /* CONFIG_IPV6 */
 278
 279
 280 /**
 281  * If no filename is given to av_open_input_file because you want to
 282  * get the local port first, then you must call this function to set
 283  * the remote server address.
 284  *
 285  * url syntax: udp://host:port[?option=val...]
 286  * option: 'ttl=n'       : set the ttl value (for multicast only)
 287  *         'localport=n' : set the local port
 288  *         'pkt_size=n'  : set max packet size
 289  *         'reuse=1'     : enable reusing the socket
 290  *
 291  * @param s1 media file context
 292  * @param uri of the remote server
 293  * @return zero if no error.
 294  */
 295 int udp_set_remote_url(URLContext *h, const char *uri)
 296 {
 297     UDPContext *s = h->priv_data;
 298     char hostname[256];
 299     int port;
 300
 301     url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &port, NULL, 0, uri);
 302
 303     /* set the destination address */
 304     s->dest_addr_len = udp_set_url(&s->dest_addr, hostname, port);
 305     if (s->dest_addr_len < 0) {
 306         return AVERROR(EIO);
 307     }
 308     s->is_multicast = is_multicast_address(&s->dest_addr);
 309
 310     return 0;
 311 }
 312
 313 /**
 314  * Return the local port used by the UDP connexion
 315  * @param s1 media file context
 316  * @return the local port number
 317  */
 318 int udp_get_local_port(URLContext *h)
 319 {
 320     UDPContext *s = h->priv_data;
 321     return s->local_port;
 322 }
 323
 324 /**
 325  * Return the udp file handle for select() usage to wait for several RTP
 326  * streams at the same time.
 327  * @param h media file context
 328  */
 329 int udp_get_file_handle(URLContext *h)
 330 {
 331     UDPContext *s = h->priv_data;
 332     return s->udp_fd;
 333 }
 334
 335 /* put it in UDP context */
 336 /* return non zero if error */
 337 static int udp_open(URLContext *h, const char *uri, int flags)
 338 {
 339     char hostname[1024];
 340     int port, udp_fd = -1, tmp, bind_ret = -1;
 341     UDPContext *s = NULL;
 342     int is_output;
 343     const char *p;
 344     char buf[256];
 345 #if !CONFIG_IPV6
 346     struct sockaddr_in my_addr;
 347 #else
 348     struct sockaddr_storage my_addr;
 349 #endif
 350     int len;
 351
 352     h->is_streamed = 1;
 353     h->max_packet_size = 1472;
 354
 355     is_output = (flags & URL_WRONLY);
 356
 357     if(!ff_network_init())
 358         return AVERROR(EIO);
 359
 360     s = av_mallocz(sizeof(UDPContext));
 361     if (!s)
 362         return AVERROR(ENOMEM);
 363
 364     h->priv_data = s;
 365     s->ttl = 16;
 366     s->buffer_size = is_output ? UDP_TX_BUF_SIZE : UDP_MAX_PKT_SIZE;
 367
 368     p = strchr(uri, '?');
 369     if (p) {
 370         s->reuse_socket = find_info_tag(buf, sizeof(buf), "reuse", p);
 371         if (find_info_tag(buf, sizeof(buf), "ttl", p)) {
 372             s->ttl = strtol(buf, NULL, 10);
 373         }
 374         if (find_info_tag(buf, sizeof(buf), "localport", p)) {
 375             s->local_port = strtol(buf, NULL, 10);
 376         }
 377         if (find_info_tag(buf, sizeof(buf), "pkt_size", p)) {
 378             h->max_packet_size = strtol(buf, NULL, 10);
 379         }
 380         if (find_info_tag(buf, sizeof(buf), "buffer_size", p)) {
 381             s->buffer_size = strtol(buf, NULL, 10);
 382         }
 383     }
 384
 385     /* fill the dest addr */
 386     url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &port, NULL, 0, uri);
 387
 388     /* XXX: fix url_split */
 389     if (hostname[0] == '\0' || hostname[0] == '?') {
 390         /* only accepts null hostname if input */
 391         if (flags & URL_WRONLY)
 392             goto fail;
 393     } else {
 394         udp_set_remote_url(h, uri);
 395     }
 396
 397     if (s->is_multicast && !(h->flags & URL_WRONLY))
 398         s->local_port = port;
 399     udp_fd = udp_socket_create(s, &my_addr, &len);
 400     if (udp_fd < 0)
 401         goto fail;
 402
 403     if (s->reuse_socket)
 404         if (setsockopt (udp_fd, SOL_SOCKET, SO_REUSEADDR, &(s->reuse_socket), sizeof(s->reuse_socket)) != 0)
 405             goto fail;
 406
 407     /* the bind is needed to give a port to the socket now */
 408     /* if multicast, try the multicast address bind first */
 409     if (s->is_multicast && !(h->flags & URL_WRONLY)) {
 410         bind_ret = bind(udp_fd,(struct sockaddr *)&s->dest_addr, len);
 411     }
 412     /* bind to the local address if not multicast or if the multicast
 413      * bind failed */
 414     if (bind_ret < 0 && bind(udp_fd,(struct sockaddr *)&my_addr, len) < 0)
 415         goto fail;
 416
 417     len = sizeof(my_addr);
 418     getsockname(udp_fd, (struct sockaddr *)&my_addr, &len);
 419     s->local_port = udp_port(&my_addr, len);
 420
 421     if (s->is_multicast) {
 422         if (h->flags & URL_WRONLY) {
 423             /* output */
 424             if (udp_set_multicast_ttl(udp_fd, s->ttl, (struct sockaddr *)&s->dest_addr) < 0)
 425                 goto fail;
 426         } else {
 427             /* input */
 428             if (udp_join_multicast_group(udp_fd, (struct sockaddr *)&s->dest_addr) < 0)
 429                 goto fail;
 430         }
 431     }
 432
 433     if (is_output) {
 434         /* limit the tx buf size to limit latency */
 435         tmp = s->buffer_size;
 436         if (setsockopt(udp_fd, SOL_SOCKET, SO_SNDBUF, &tmp, sizeof(tmp)) < 0) {
 437             av_log(NULL, AV_LOG_ERROR, "setsockopt(SO_SNDBUF): %s\n", strerror(errno));
 438             goto fail;
 439         }
 440     } else {
 441         /* set udp recv buffer size to the largest possible udp packet size to
 442          * avoid losing data on OSes that set this too low by default. */
 443         tmp = s->buffer_size;
 444         if (setsockopt(udp_fd, SOL_SOCKET, SO_RCVBUF, &tmp, sizeof(tmp)) < 0) {
 445             av_log(NULL, AV_LOG_WARNING, "setsockopt(SO_RECVBUF): %s\n", strerror(errno));
 446         }
 447         /* make the socket non-blocking */
 448         ff_socket_nonblock(udp_fd, 1);
 449     }
 450
 451     s->udp_fd = udp_fd;
 452     return 0;
 453  fail:
 454     if (udp_fd >= 0)
 455         closesocket(udp_fd);
 456     av_free(s);
 457     return AVERROR(EIO);
 458 }
 459
 460 static int udp_read(URLContext *h, uint8_t *buf, int size)
 461 {
 462     UDPContext *s = h->priv_data;
 463     int len;
 464     fd_set rfds;
 465     int ret;
 466     struct timeval tv;
 467
 468     for(;;) {
 469         if (url_interrupt_cb())
 470             return AVERROR(EINTR);
 471         FD_ZERO(&rfds);
 472         FD_SET(s->udp_fd, &rfds);
 473         tv.tv_sec = 0;
 474         tv.tv_usec = 100 * 1000;
 475         ret = select(s->udp_fd + 1, &rfds, NULL, NULL, &tv);
 476         if (ret < 0)
 477             return AVERROR(EIO);
 478         if (!(ret > 0 && FD_ISSET(s->udp_fd, &rfds)))
 479             continue;
 480         len = recv(s->udp_fd, buf, size, 0);
 481         if (len < 0) {
 482             if (ff_neterrno() != FF_NETERROR(EAGAIN) &&
 483                 ff_neterrno() != FF_NETERROR(EINTR))
 484                 return AVERROR(EIO);
 485         } else {
 486             break;
 487         }
 488     }
 489     return len;
 490 }
 491
 492 static int udp_write(URLContext *h, uint8_t *buf, int size)
 493 {
 494     UDPContext *s = h->priv_data;
 495     int ret;
 496
 497     for(;;) {
 498         ret = sendto (s->udp_fd, buf, size, 0,
 499                       (struct sockaddr *) &s->dest_addr,
 500                       s->dest_addr_len);
 501         if (ret < 0) {
 502             if (ff_neterrno() != FF_NETERROR(EINTR) &&
 503                 ff_neterrno() != FF_NETERROR(EAGAIN))
 504                 return AVERROR(EIO);
 505         } else {
 506             break;
 507         }
 508     }
 509     return size;
 510 }
 511
 512 static int udp_close(URLContext *h)
 513 {
 514     UDPContext *s = h->priv_data;
 515
 516     if (s->is_multicast && !(h->flags & URL_WRONLY))
 517         udp_leave_multicast_group(s->udp_fd, (struct sockaddr *)&s->dest_addr);
 518     closesocket(s->udp_fd);
 519     ff_network_close();
 520     av_free(s);
 521     return 0;
 522 }
 523
 524 URLProtocol udp_protocol = {
 525     "udp",
 526     udp_open,
 527     udp_read,
 528     udp_write,
 529     NULL, /* seek */
 530     udp_close,
 531 };