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