stream/librtsp/rtsp_rtp.c

   1 /*
   2  *  Copyright (C) 2006 Benjamin Zores
   3  *   based on the Freebox patch for xine by Vincent Mussard
   4  *   but with many enhancements for better RTSP RFC compliance.
   5  *
   6  *   This program is free software; you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation; either version 2 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *   This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *   You should have received a copy of the GNU General Public License
  17  *  along with this program; if not, write to the Free Software Foundation,
  18  *  Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  19  */
  20
  21 #include <unistd.h>
  22 #include <stdio.h>
  23 #include <string.h>
  24 #include <errno.h>
  25 #include <stdlib.h>
  26 #include <sys/types.h>
  27 #include <inttypes.h>
  28
  29 #include "config.h"
  30
  31 #if !HAVE_WINSOCK2_H
  32 #include <netdb.h>
  33 #include <netinet/in.h>
  34 #include <sys/socket.h>
  35 #include <arpa/inet.h>
  36 #else
  37 #include <winsock2.h>
  38 #include <ws2tcpip.h>
  39 #endif
  40
  41 #include "mp_msg.h"
  42 #include "rtsp.h"
  43 #include "rtsp_rtp.h"
  44 #include "rtsp_session.h"
  45 #include "stream/network.h"
  46 #include "stream/freesdp/common.h"
  47 #include "stream/freesdp/parser.h"
  48 #include "libavutil/avstring.h"
  49
  50 #define RTSP_DEFAULT_PORT 31336
  51 #define MAX_LENGTH 256
  52
  53 #define RTSP_ACCEPT_SDP "Accept: application/sdp"
  54 #define RTSP_CONTENT_LENGTH "Content-length"
  55 #define RTSP_CONTENT_TYPE "Content-Type"
  56 #define RTSP_APPLICATION_SDP "application/sdp"
  57 #define RTSP_RANGE "Range: "
  58 #define RTSP_NPT_NOW "npt=now-"
  59 #define RTSP_MEDIA_CONTAINER_MPEG_TS "33"
  60 #define RTSP_TRANSPORT_REQUEST "Transport: RTP/AVP;%s;%s%i-%i;mode=\"PLAY\""
  61
  62 #define RTSP_TRANSPORT_MULTICAST "multicast"
  63 #define RTSP_TRANSPORT_UNICAST "unicast"
  64
  65 #define RTSP_MULTICAST_PORT "port="
  66 #define RTSP_UNICAST_CLIENT_PORT "client_port="
  67 #define RTSP_UNICAST_SERVER_PORT "server_port="
  68 #define RTSP_SETUP_DESTINATION "destination="
  69
  70 #define RTSP_SESSION "Session"
  71 #define RTSP_TRANSPORT "Transport"
  72
  73 /* hardcoded RTCP RR - this is _NOT_ RFC compliant */
  74 #define RTCP_RR_SIZE 32
  75 #define RTCP_RR "\201\311\0\7(.JD\31+\306\343\0\0\0\0\0\0/E\0\0\2&\0\0\0\0\0\0\0\0\201"
  76 #define RTCP_SEND_FREQUENCY 1024
  77
  78 int rtsp_port = 0;
  79 char *rtsp_destination = NULL;
  80
  81 void
  82 rtcp_send_rr (rtsp_t *s, struct rtp_rtsp_session_t *st)
  83 {
  84   if (st->rtcp_socket == -1)
  85     return;
  86
  87   /* send RTCP RR every RTCP_SEND_FREQUENCY packets
  88    * FIXME : NOT CORRECT, HARDCODED, BUT MAKES SOME SERVERS HAPPY
  89    * not rfc compliant
  90    * http://www.faqs.org/rfcs/rfc1889.html chapter 6 for RTCP
  91    */
  92
  93   if (st->count == RTCP_SEND_FREQUENCY)
  94   {
  95     char rtcp_content[RTCP_RR_SIZE];
  96     strcpy (rtcp_content, RTCP_RR);
  97     send (st->rtcp_socket, rtcp_content, RTCP_RR_SIZE, DEFAULT_SEND_FLAGS);
  98
  99     /* ping RTSP server to keep connection alive.
 100        we use OPTIONS instead of PING as not all servers support it */
 101     rtsp_request_options (s, "*");
 102     st->count = 0;
 103   }
 104   else
 105     st->count++;
 106 }
 107
 108 static struct rtp_rtsp_session_t *
 109 rtp_session_new (void)
 110 {
 111   struct rtp_rtsp_session_t *st = NULL;
 112
 113   st = malloc (sizeof (struct rtp_rtsp_session_t));
 114
 115   st->rtp_socket = -1;
 116   st->rtcp_socket = -1;
 117   st->control_url = NULL;
 118   st->count = 0;
 119
 120   return st;
 121 }
 122
 123 void
 124 rtp_session_free (struct rtp_rtsp_session_t *st)
 125 {
 126   if (!st)
 127     return;
 128
 129   if (st->rtp_socket != -1)
 130     close (st->rtp_socket);
 131   if (st->rtcp_socket != -1)
 132     close (st->rtcp_socket);
 133
 134   free (st->control_url);
 135   free (st);
 136 }
 137
 138 static void
 139 rtp_session_set_fd (struct rtp_rtsp_session_t *st,
 140                     int rtp_sock, int rtcp_sock)
 141 {
 142   if (!st)
 143     return;
 144
 145   st->rtp_socket = rtp_sock;
 146   st->rtcp_socket = rtcp_sock;
 147 }
 148
 149 static int
 150 parse_port (const char *line, const char *param,
 151             int *rtp_port, int *rtcp_port)
 152 {
 153   char *parse1;
 154   char *parse2;
 155   char *parse3;
 156
 157   char *line_copy = strdup (line);
 158
 159   parse1 = strstr (line_copy, param);
 160
 161   if (parse1)
 162   {
 163     parse2 = strstr (parse1, "-");
 164
 165     if (parse2)
 166     {
 167       parse3 = strstr (parse2, ";");
 168
 169       if (parse3)
 170         parse3[0] = 0;
 171
 172       parse2[0] = 0;
 173     }
 174     else
 175     {
 176       free (line_copy);
 177       return 0;
 178     }
 179   }
 180   else
 181   {
 182     free (line_copy);
 183     return 0;
 184   }
 185
 186   *rtp_port = atoi (parse1 + strlen (param));
 187   *rtcp_port = atoi (parse2 + 1);
 188
 189   free (line_copy);
 190
 191   return 1;
 192 }
 193
 194 static char *
 195 parse_destination (const char *line)
 196 {
 197   char *parse1;
 198   char *parse2;
 199
 200   char *dest = NULL;
 201   char *line_copy = strdup (line);
 202   int len;
 203
 204   parse1 = strstr (line_copy, RTSP_SETUP_DESTINATION);
 205   if (!parse1)
 206   {
 207     free (line_copy);
 208     return NULL;
 209   }
 210
 211   parse2 = strstr (parse1, ";");
 212   if (!parse2)
 213   {
 214     free (line_copy);
 215     return NULL;
 216   }
 217
 218   len = strlen (parse1) - strlen (parse2)
 219     - strlen (RTSP_SETUP_DESTINATION) + 1;
 220   dest = (char *) malloc (len + 1);
 221   av_strlcpy (dest, parse1 + strlen (RTSP_SETUP_DESTINATION), len);
 222   free (line_copy);
 223
 224   return dest;
 225 }
 226
 227 static int
 228 rtcp_connect (int client_port, int server_port, const char* server_hostname)
 229 {
 230   struct sockaddr_in sin;
 231   struct hostent *hp;
 232   int s;
 233
 234   if (client_port <= 1023)
 235     return -1;
 236
 237   s = socket (PF_INET, SOCK_DGRAM, IPPROTO_UDP);
 238   if (s == -1)
 239     return -1;
 240
 241   hp = gethostbyname (server_hostname);
 242   if (!hp)
 243   {
 244     close (s);
 245     return -1;
 246   }
 247
 248   memset(&sin, 0, sizeof(sin));
 249   sin.sin_family = AF_INET;
 250   sin.sin_addr.s_addr = INADDR_ANY;
 251   sin.sin_port = htons (client_port);
 252
 253   if (bind (s, (struct sockaddr *) &sin, sizeof (sin)))
 254   {
 255 #if !HAVE_WINSOCK2_H
 256     if (errno != EINPROGRESS)
 257 #else
 258     if (WSAGetLastError() != WSAEINPROGRESS)
 259 #endif
 260     {
 261       close (s);
 262       return -1;
 263     }
 264   }
 265
 266   sin.sin_family = AF_INET;
 267   memcpy (&(sin.sin_addr.s_addr), hp->h_addr, sizeof (hp->h_addr));
 268   sin.sin_port = htons (server_port);
 269
 270   /* datagram socket */
 271   if (connect (s, (struct sockaddr *) &sin, sizeof (sin)) < 0)
 272   {
 273     close (s);
 274     return -1;
 275   }
 276
 277   return s;
 278 }
 279
 280 static int
 281 rtp_connect (char *hostname, int port)
 282 {
 283   struct sockaddr_in sin;
 284   struct timeval tv;
 285   int err, err_len;
 286   int rxsockbufsz;
 287   int s;
 288   fd_set set;
 289
 290   if (port <= 1023)
 291     return -1;
 292
 293   s = socket (PF_INET, SOCK_DGRAM, 0);
 294   if (s == -1)
 295     return -1;
 296
 297   memset(&sin, 0, sizeof(sin));
 298   sin.sin_family = AF_INET;
 299   if (!hostname || !strcmp (hostname, "0.0.0.0"))
 300     sin.sin_addr.s_addr = htonl (INADDR_ANY);
 301   else
 302 #if HAVE_INET_PTON
 303     inet_pton (AF_INET, hostname, &sin.sin_addr);
 304 #elif HAVE_INET_ATON
 305     inet_aton (hostname, &sin.sin_addr);
 306 #elif HAVE_WINSOCK2_H
 307     sin.sin_addr.s_addr = htonl (INADDR_ANY);
 308 #endif
 309   sin.sin_port = htons (port);
 310
 311   /* Increase the socket rx buffer size to maximum -- this is UDP */
 312   rxsockbufsz = 240 * 1024;
 313   if (setsockopt (s, SOL_SOCKET, SO_RCVBUF,
 314                   &rxsockbufsz, sizeof (rxsockbufsz)))
 315     mp_msg (MSGT_OPEN, MSGL_ERR, "Couldn't set receive socket buffer size\n");
 316
 317   /* if multicast address, add membership */
 318   if ((ntohl (sin.sin_addr.s_addr) >> 28) == 0xe)
 319   {
 320     struct ip_mreq mcast;
 321     mcast.imr_multiaddr.s_addr = sin.sin_addr.s_addr;
 322     mcast.imr_interface.s_addr = 0;
 323
 324     if (setsockopt (s, IPPROTO_IP, IP_ADD_MEMBERSHIP, &mcast, sizeof (mcast)))
 325     {
 326       mp_msg (MSGT_OPEN, MSGL_ERR, "IP_ADD_MEMBERSHIP failed\n");
 327       close (s);
 328       return -1;
 329     }
 330   }
 331
 332   /* datagram socket */
 333   if (bind (s, (struct sockaddr *) &sin, sizeof (sin)))
 334   {
 335 #if !HAVE_WINSOCK2_H
 336     if (errno != EINPROGRESS)
 337 #else
 338     if (WSAGetLastError() != WSAEINPROGRESS)
 339 #endif
 340     {
 341       mp_msg (MSGT_OPEN, MSGL_ERR, "bind: %s\n", strerror (errno));
 342       close (s);
 343       return -1;
 344     }
 345   }
 346
 347   tv.tv_sec = 1; /* 1 second timeout */
 348   tv.tv_usec = 0;
 349
 350   FD_ZERO (&set);
 351   FD_SET (s, &set);
 352
 353   err = select (s + 1, &set, NULL, NULL, &tv);
 354   if (err < 0)
 355   {
 356     mp_msg (MSGT_OPEN, MSGL_ERR, "Select failed: %s\n", strerror (errno));
 357     close (s);
 358     return -1;
 359   }
 360   else if (err == 0)
 361   {
 362     mp_msg (MSGT_OPEN, MSGL_ERR, "Timeout! No data from host %s\n", hostname);
 363     close (s);
 364     return -1;
 365   }
 366
 367   err_len = sizeof (err);
 368   getsockopt (s, SOL_SOCKET, SO_ERROR, &err, (socklen_t *) &err_len);
 369   if (err)
 370   {
 371     mp_msg (MSGT_OPEN, MSGL_ERR, "Socket error: %d\n", err);
 372     close (s);
 373     return -1;
 374   }
 375
 376   return s;
 377 }
 378
 379 static int
 380 is_multicast_address (char *addr)
 381 {
 382   struct sockaddr_in sin;
 383
 384   if (!addr)
 385     return -1;
 386
 387   sin.sin_family = AF_INET;
 388
 389 #if HAVE_INET_PTON
 390     inet_pton (AF_INET, addr, &sin.sin_addr);
 391 #elif HAVE_INET_ATON
 392     inet_aton (addr, &sin.sin_addr);
 393 #elif HAVE_WINSOCK2_H
 394     sin.sin_addr.s_addr = htonl (INADDR_ANY);
 395 #endif
 396
 397   if ((ntohl (sin.sin_addr.s_addr) >> 28) == 0xe)
 398     return 1;
 399
 400   return 0;
 401 }
 402
 403 struct rtp_rtsp_session_t *
 404 rtp_setup_and_play (rtsp_t *rtsp_session)
 405 {
 406   struct rtp_rtsp_session_t* rtp_session = NULL;
 407   const fsdp_media_description_t *med_dsc = NULL;
 408   char temp_buf[MAX_LENGTH + 1];
 409   char npt[256];
 410
 411   char* answer;
 412   char* sdp;
 413   char *server_addr = NULL;
 414   char *destination = NULL;
 415
 416   int statut;
 417   int content_length = 0;
 418   int is_multicast = 0;
 419
 420   fsdp_description_t *dsc = NULL;
 421   fsdp_error_t result;
 422
 423   int client_rtp_port = -1;
 424   int client_rtcp_port = -1;
 425   int server_rtp_port = -1;
 426   int server_rtcp_port = -1;
 427   int rtp_sock = -1;
 428   int rtcp_sock = -1;
 429
 430   /* 1. send a RTSP DESCRIBE request to server */
 431   rtsp_schedule_field (rtsp_session, RTSP_ACCEPT_SDP);
 432   statut = rtsp_request_describe (rtsp_session, NULL);
 433   if (statut < 200 || statut > 299)
 434     return NULL;
 435
 436   answer = rtsp_search_answers (rtsp_session, RTSP_CONTENT_LENGTH);
 437   if (answer)
 438     content_length = atoi (answer);
 439   else
 440     return NULL;
 441
 442   answer = rtsp_search_answers (rtsp_session, RTSP_CONTENT_TYPE);
 443   if (!answer || !strstr (answer, RTSP_APPLICATION_SDP))
 444     return NULL;
 445
 446   /* 2. read SDP message from server */
 447   sdp = (char *) malloc (content_length + 1);
 448   if (rtsp_read_data (rtsp_session, sdp, content_length) <= 0)
 449   {
 450     free (sdp);
 451     return NULL;
 452   }
 453   sdp[content_length] = 0;
 454
 455   /* 3. parse SDP message */
 456   dsc = fsdp_description_new ();
 457   result = fsdp_parse (sdp, dsc);
 458   if (result != FSDPE_OK)
 459   {
 460     free (sdp);
 461     fsdp_description_delete (dsc);
 462     return NULL;
 463   }
 464   mp_msg (MSGT_OPEN, MSGL_V, "SDP:\n%s\n", sdp);
 465   free (sdp);
 466
 467   /* 4. check for number of media streams: only one is supported */
 468   if (fsdp_get_media_count (dsc) != 1)
 469   {
 470     mp_msg (MSGT_OPEN, MSGL_ERR,
 471             "A single media stream only is supported atm.\n");
 472     fsdp_description_delete (dsc);
 473     return NULL;
 474   }
 475
 476   /* 5. set the Normal Play Time parameter
 477    *    use range provided by server in SDP or start now if empty */
 478   sprintf (npt, RTSP_RANGE);
 479   if (fsdp_get_range (dsc))
 480     strcat (npt, fsdp_get_range (dsc));
 481   else
 482     strcat (npt, RTSP_NPT_NOW);
 483
 484   /* 5. check for a valid media stream */
 485   med_dsc = fsdp_get_media (dsc, 0);
 486   if (!med_dsc)
 487   {
 488     fsdp_description_delete (dsc);
 489     return NULL;
 490   }
 491
 492   /* 6. parse the `m=<media>  <port>  <transport> <fmt list>' line */
 493
 494   /* check for an A/V media */
 495   if (fsdp_get_media_type (med_dsc) != FSDP_MEDIA_VIDEO &&
 496       fsdp_get_media_type (med_dsc) != FSDP_MEDIA_AUDIO)
 497   {
 498     fsdp_description_delete (dsc);
 499     return NULL;
 500   }
 501
 502   /* only RTP/AVP transport method is supported right now */
 503   if (fsdp_get_media_transport_protocol (med_dsc) != FSDP_TP_RTP_AVP)
 504   {
 505     fsdp_description_delete (dsc);
 506     return NULL;
 507   }
 508
 509   /* only MPEG-TS is supported at the moment */
 510   if (!fsdp_get_media_format (med_dsc, 0) ||
 511       !strstr (fsdp_get_media_format (med_dsc, 0),
 512                RTSP_MEDIA_CONTAINER_MPEG_TS))
 513   {
 514     fsdp_description_delete (dsc);
 515     return NULL;
 516   }
 517
 518   /* get client port (if any) advised by server */
 519   client_rtp_port = fsdp_get_media_port (med_dsc);
 520   if (client_rtp_port == -1)
 521   {
 522     fsdp_description_delete (dsc);
 523     return NULL;
 524   }
 525
 526   /* if client_rtp_port = 0 => let client randomly pick one */
 527   if (client_rtp_port == 0)
 528   {
 529     /* TODO: we should check if the port is in use first */
 530     if (rtsp_port)
 531       client_rtp_port = rtsp_port;
 532     else
 533       client_rtp_port = RTSP_DEFAULT_PORT;
 534   }
 535
 536   /* RTCP port generally is RTP port + 1 */
 537   client_rtcp_port = client_rtp_port + 1;
 538
 539   mp_msg (MSGT_OPEN, MSGL_V,
 540           "RTP Port from SDP appears to be: %d\n", client_rtp_port);
 541   mp_msg (MSGT_OPEN, MSGL_V,
 542           "RTCP Port from SDP appears to be: %d\n", client_rtcp_port);
 543
 544   /* 7. parse the `c=<network type> <addr type> <connection address>' line */
 545
 546   /* check for a valid media network type (inet) */
 547   if (fsdp_get_media_network_type (med_dsc) != FSDP_NETWORK_TYPE_INET)
 548   {
 549     /* no control for media: try global one instead */
 550     if (fsdp_get_global_conn_network_type (dsc) != FSDP_NETWORK_TYPE_INET)
 551     {
 552       fsdp_description_delete (dsc);
 553       return NULL;
 554     }
 555   }
 556
 557   /* only IPv4 is supported atm. */
 558   if (fsdp_get_media_address_type (med_dsc) != FSDP_ADDRESS_TYPE_IPV4)
 559   {
 560     /* no control for media: try global one instead */
 561     if (fsdp_get_global_conn_address_type (dsc) != FSDP_ADDRESS_TYPE_IPV4)
 562     {
 563       fsdp_description_delete (dsc);
 564       return NULL;
 565     }
 566   }
 567
 568   /* get the media server address to connect to */
 569   if (fsdp_get_media_address (med_dsc))
 570     server_addr = strdup (fsdp_get_media_address (med_dsc));
 571   else if (fsdp_get_global_conn_address (dsc))
 572   {
 573     /* no control for media: try global one instead */
 574     server_addr = strdup (fsdp_get_global_conn_address (dsc));
 575   }
 576
 577   if (!server_addr)
 578   {
 579     fsdp_description_delete (dsc);
 580     return NULL;
 581   }
 582
 583   /* check for a UNICAST or MULTICAST address to connect to */
 584   is_multicast = is_multicast_address (server_addr);
 585
 586   /* 8. initiate an RTP session */
 587   rtp_session = rtp_session_new ();
 588   if (!rtp_session)
 589   {
 590     free (server_addr);
 591     fsdp_description_delete (dsc);
 592     return NULL;
 593   }
 594
 595   /* get the media control URL */
 596   if (fsdp_get_media_control (med_dsc, 0))
 597     rtp_session->control_url = strdup (fsdp_get_media_control (med_dsc, 0));
 598   fsdp_description_delete (dsc);
 599   if (!rtp_session->control_url)
 600   {
 601     free (server_addr);
 602     rtp_session_free (rtp_session);
 603     return NULL;
 604   }
 605
 606   /* 9. create the payload for RTSP SETUP request */
 607   memset (temp_buf, '\0', MAX_LENGTH);
 608   snprintf (temp_buf, MAX_LENGTH,
 609             RTSP_TRANSPORT_REQUEST,
 610             is_multicast ? RTSP_TRANSPORT_MULTICAST : RTSP_TRANSPORT_UNICAST,
 611             is_multicast ? RTSP_MULTICAST_PORT : RTSP_UNICAST_CLIENT_PORT,
 612             client_rtp_port, client_rtcp_port);
 613   mp_msg (MSGT_OPEN, MSGL_V, "RTSP Transport: %s\n", temp_buf);
 614
 615   rtsp_unschedule_field (rtsp_session, RTSP_SESSION);
 616   rtsp_schedule_field (rtsp_session, temp_buf);
 617
 618   /* 10. check for the media control URL type and initiate RTSP SETUP */
 619   if (!strncmp (rtp_session->control_url, "rtsp://", 7)) /* absolute URL */
 620     statut = rtsp_request_setup (rtsp_session,
 621                                  rtp_session->control_url, NULL);
 622   else /* relative URL */
 623     statut = rtsp_request_setup (rtsp_session,
 624                                  NULL, rtp_session->control_url);
 625
 626   if (statut < 200 || statut > 299)
 627   {
 628     free (server_addr);
 629     rtp_session_free (rtp_session);
 630     return NULL;
 631   }
 632
 633   /* 11. parse RTSP SETUP response: we need it to actually determine
 634    *     the real address and port to connect to */
 635   answer = rtsp_search_answers (rtsp_session, RTSP_TRANSPORT);
 636   if (!answer)
 637   {
 638     free (server_addr);
 639     rtp_session_free (rtp_session);
 640     return NULL;
 641   }
 642
 643   /* check for RTP and RTCP ports to bind according to how request was done */
 644   is_multicast = 0;
 645   if (strstr (answer, RTSP_TRANSPORT_MULTICAST))
 646     is_multicast = 1;
 647
 648   if (is_multicast)
 649     parse_port (answer, RTSP_MULTICAST_PORT,
 650                 &client_rtp_port, &client_rtcp_port);
 651   else
 652   {
 653     parse_port (answer, RTSP_UNICAST_CLIENT_PORT,
 654                 &client_rtp_port, &client_rtcp_port);
 655     parse_port (answer, RTSP_UNICAST_SERVER_PORT,
 656                 &server_rtp_port, &server_rtcp_port);
 657   }
 658
 659   /* now check network settings as determined by server */
 660   if (rtsp_destination)
 661     destination = strdup (rtsp_destination);
 662   else
 663     destination = parse_destination (answer);
 664   if (!destination)
 665     destination = strdup (server_addr);
 666   free (server_addr);
 667
 668   mp_msg (MSGT_OPEN, MSGL_V, "RTSP Destination: %s\n", destination);
 669   mp_msg (MSGT_OPEN, MSGL_V, "Client RTP port : %d\n", client_rtp_port);
 670   mp_msg (MSGT_OPEN, MSGL_V, "Client RTCP port : %d\n", client_rtcp_port);
 671   mp_msg (MSGT_OPEN, MSGL_V, "Server RTP port : %d\n", server_rtp_port);
 672   mp_msg (MSGT_OPEN, MSGL_V, "Server RTCP port : %d\n", server_rtcp_port);
 673
 674   /* 12. performs RTSP PLAY request */
 675   rtsp_schedule_field (rtsp_session, npt);
 676   statut = rtsp_request_play (rtsp_session, NULL);
 677   if (statut < 200 || statut > 299)
 678   {
 679     free (destination);
 680     rtp_session_free (rtp_session);
 681     return NULL;
 682   }
 683
 684   /* 13. create RTP and RTCP connections */
 685   rtp_sock = rtp_connect (destination, client_rtp_port);
 686   rtcp_sock = rtcp_connect (client_rtcp_port, server_rtcp_port, destination);
 687   rtp_session_set_fd (rtp_session, rtp_sock, rtcp_sock);
 688   free (destination);
 689
 690   mp_msg (MSGT_OPEN, MSGL_V, "RTP Sock : %d\nRTCP Sock : %d\n",
 691           rtp_session->rtp_socket, rtp_session->rtcp_socket);
 692
 693   if (rtp_session->rtp_socket == -1)
 694   {
 695     rtp_session_free (rtp_session);
 696     return NULL;
 697   }
 698
 699   return rtp_session;
 700 }