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