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