git.sesse.net Git - vlc/blob - src/stream_output/sap.c

   1 /*****************************************************************************
   2  * sap.c : SAP announce handler
   3  *****************************************************************************
   4  * Copyright (C) 2002-2007 the VideoLAN team
   5  * $Id$
   6  *
   7  * Authors: Clément Stenac <zorglub@videolan.org>
   8  *          Rémi Denis-Courmont <rem # videolan.org>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  23  *****************************************************************************/
  24
  25 /*****************************************************************************
  26  * Preamble
  27  *****************************************************************************/
  28
  29 #ifdef HAVE_CONFIG_H
  30 # include "config.h"
  31 #endif
  32
  33 #include <vlc/vlc.h>
  34
  35 #include <stdlib.h>                                                /* free() */
  36 #include <stdio.h>                                              /* sprintf() */
  37 #include <string.h>
  38 #include <ctype.h>                                  /* tolower(), isxdigit() */
  39 #include <assert.h>
  40
  41 #include <vlc_sout.h>
  42 #include <vlc_network.h>
  43 #include <vlc_charset.h>
  44
  45 #include "stream_output.h"
  46
  47 /* SAP is always on that port */
  48 #define SAP_PORT 9875
  49
  50 #define DEFAULT_PORT "1234"
  51
  52 #undef EXTRA_DEBUG
  53
  54 /* SAP Specific structures */
  55
  56 /* 100ms */
  57 #define SAP_IDLE ((mtime_t)(0.100*CLOCK_FREQ))
  58 #define SAP_MAX_BUFFER 65534
  59 #define MIN_INTERVAL 2
  60 #define MAX_INTERVAL 300
  61
  62 /* A SAP announce address. For each of these, we run the
  63  * control flow algorithm */
  64 struct sap_address_t
  65 {
  66     char *psz_address;
  67     struct sockaddr_storage orig;
  68     socklen_t origlen;
  69     int i_rfd; /* Read socket */
  70     int i_wfd; /* Write socket */
  71
  72     /* Used for flow control */
  73     mtime_t t1;
  74     vlc_bool_t b_enabled;
  75     vlc_bool_t b_ready;
  76     int i_interval;
  77     int i_buff;
  78     int i_limit;
  79 };
  80
  81 /* A SAP session descriptor, enqueued in the SAP handler queue */
  82 struct sap_session_t {
  83     uint8_t       *psz_data;
  84     unsigned      i_length;
  85     sap_address_t *p_address;
  86     session_descriptor_t *p_sd;
  87
  88     /* Last and next send */
  89     mtime_t        i_last;
  90     mtime_t        i_next;
  91 };
  92
  93 /*****************************************************************************
  94  * Local prototypes
  95  *****************************************************************************/
  96 static void RunThread( vlc_object_t *p_this);
  97 static int ComputeRate( sap_address_t *p_address );
  98
  99 static int announce_SendSAPAnnounce( sap_handler_t *p_sap,
 100                                      sap_session_t *p_session );
 101
 102
 103 static int announce_SAPAnnounceAdd( sap_handler_t *p_sap,
 104                              session_descriptor_t *p_session );
 105
 106 static int announce_SAPAnnounceDel( sap_handler_t *p_sap,
 107                              session_descriptor_t *p_session );
 108
 109 static void announce_SAPHandlerDestructor( vlc_object_t *p_this );
 110
 111
 112 /**
 113  * Create the SAP handler
 114  *
 115  * \param p_announce the parent announce_handler
 116  * \return the newly created SAP handler or NULL on error
 117  */
 118 sap_handler_t *announce_SAPHandlerCreate( announce_handler_t *p_announce )
 119 {
 120     sap_handler_t *p_sap;
 121
 122     p_sap = vlc_object_create( p_announce, sizeof( sap_handler_t ) );
 123     if( !p_sap )
 124     {
 125         msg_Err( p_announce, "out of memory" );
 126         return NULL;
 127     }
 128
 129     p_sap->psz_object_name = "sap announcer";
 130
 131     vlc_mutex_init( p_sap, &p_sap->object_lock );
 132
 133     p_sap->pf_add = announce_SAPAnnounceAdd;
 134     p_sap->pf_del = announce_SAPAnnounceDel;
 135
 136     p_sap->i_sessions = 0;
 137     p_sap->i_addresses = 0;
 138     p_sap->i_current_session = 0;
 139
 140     p_sap->b_control = config_GetInt( p_sap, "sap-flow-control");
 141
 142     if( vlc_thread_create( p_sap, "sap handler", RunThread,
 143                        VLC_THREAD_PRIORITY_LOW, VLC_FALSE ) )
 144     {
 145         msg_Dbg( p_announce, "unable to spawn SAP handler thread");
 146         vlc_object_release( p_sap );
 147         return NULL;
 148     }
 149
 150     vlc_object_set_destructor( p_sap, announce_SAPHandlerDestructor );
 151
 152     msg_Dbg( p_announce, "thread created, %i sessions", p_sap->i_sessions);
 153
 154     return p_sap;
 155 }
 156
 157 static void announce_SAPHandlerDestructor( vlc_object_t * p_this )
 158 {
 159     sap_handler_t *p_sap = (sap_handler_t *)p_this;
 160     int i;
 161
 162     /* Free the remaining sessions */
 163     for( i = 0 ; i< p_sap->i_sessions ; i++)
 164     {
 165         sap_session_t *p_session = p_sap->pp_sessions[i];
 166         FREENULL( p_session->psz_data );
 167         REMOVE_ELEM( p_sap->pp_sessions, p_sap->i_sessions , i );
 168         FREENULL( p_session );
 169     }
 170
 171     /* Free the remaining addresses */
 172     for( i = 0 ; i< p_sap->i_addresses ; i++)
 173     {
 174         sap_address_t *p_address = p_sap->pp_addresses[i];
 175         FREENULL( p_address->psz_address );
 176         if( p_address->i_rfd > -1 )
 177         {
 178             net_Close( p_address->i_rfd );
 179         }
 180         if( p_address->i_wfd > -1 && p_sap->b_control )
 181         {
 182             net_Close( p_address->i_wfd );
 183         }
 184         REMOVE_ELEM( p_sap->pp_addresses, p_sap->i_addresses, i );
 185         FREENULL( p_address );
 186     }
 187 }
 188
 189 /**
 190  * main SAP handler thread
 191  * \param p_this the SAP Handler object
 192  * \return nothing
 193  */
 194 static void RunThread( vlc_object_t *p_this)
 195 {
 196     sap_handler_t *p_sap = (sap_handler_t*)p_this;
 197     sap_session_t *p_session;
 198
 199     while( !p_sap->b_die )
 200     {
 201         int i;
 202
 203         /* If needed, get the rate info */
 204         if( p_sap->b_control == VLC_TRUE )
 205         {
 206             for( i = 0 ; i< p_sap->i_addresses ; i++)
 207             {
 208                 if( p_sap->pp_addresses[i]->b_enabled == VLC_TRUE )
 209                 {
 210                     ComputeRate( p_sap->pp_addresses[i] );
 211                 }
 212             }
 213         }
 214
 215         /* Find the session to announce */
 216         vlc_mutex_lock( &p_sap->object_lock );
 217         if( p_sap->i_sessions > p_sap->i_current_session + 1)
 218         {
 219             p_sap->i_current_session++;
 220         }
 221         else if( p_sap->i_sessions > 0)
 222         {
 223             p_sap->i_current_session = 0;
 224         }
 225         else
 226         {
 227             vlc_mutex_unlock( &p_sap->object_lock );
 228             msleep( SAP_IDLE );
 229             continue;
 230         }
 231         p_session = p_sap->pp_sessions[p_sap->i_current_session];
 232         vlc_mutex_unlock( &p_sap->object_lock );
 233
 234         /* And announce it */
 235         if( p_session->p_address->b_enabled == VLC_TRUE &&
 236             p_session->p_address->b_ready == VLC_TRUE )
 237         {
 238             announce_SendSAPAnnounce( p_sap, p_session );
 239         }
 240
 241         msleep( SAP_IDLE );
 242     }
 243 }
 244
 245 /* Add a SAP announce */
 246 static int announce_SAPAnnounceAdd( sap_handler_t *p_sap,
 247                              session_descriptor_t *p_session )
 248 {
 249     int i;
 250     char psz_addr[NI_MAXNUMERICHOST];
 251     vlc_bool_t b_ipv6 = VLC_FALSE, b_ssm = VLC_FALSE;
 252     sap_session_t *p_sap_session;
 253     mtime_t i_hash;
 254     struct sockaddr_storage addr;
 255     socklen_t addrlen;
 256
 257     vlc_mutex_lock( &p_sap->object_lock );
 258     addrlen = p_session->addrlen;
 259     if ((addrlen == 0) || (addrlen > sizeof (addr)))
 260     {
 261         vlc_mutex_unlock( &p_sap->object_lock );
 262         msg_Err( p_sap, "No/invalid address specified for SAP announce" );
 263         return VLC_EGENERIC;
 264     }
 265
 266     /* Determine SAP multicast address automatically */
 267     memcpy (&addr, &p_session->addr, addrlen);
 268
 269     switch( p_session->addr.ss_family )
 270     {
 271 #if defined (HAVE_INET_PTON) || defined (WIN32)
 272         case AF_INET6:
 273         {
 274             /* See RFC3513 for list of valid IPv6 scopes */
 275             struct in6_addr *a6 = &((struct sockaddr_in6 *)&addr)->sin6_addr;
 276
 277             memcpy( a6->s6_addr + 2, "\x00\x00\x00\x00\x00\x00"
 278                    "\x00\x00\x00\x00\x00\x02\x7f\xfe", 14 );
 279             if( IN6_IS_ADDR_MULTICAST( a6 ) )
 280             {
 281                 /* SSM <=> ff3x::/32 */
 282                 b_ssm = (U32_AT (a6->s6_addr) & 0xfff0ffff) == 0xff300000;
 283
 284                 /* force flags to zero, preserve scope */
 285                 a6->s6_addr[1] &= 0xf;
 286             }
 287             else
 288                 /* Unicast IPv6 - assume global scope */
 289                 memcpy( a6->s6_addr, "\xff\x0e", 2 );
 290
 291             b_ipv6 = VLC_TRUE;
 292             break;
 293         }
 294 #endif
 295
 296         case AF_INET:
 297         {
 298             /* See RFC2365 for IPv4 scopes */
 299             uint32_t ipv4;
 300
 301             ipv4 = ntohl( ((struct sockaddr_in *)&addr)->sin_addr.s_addr );
 302             /* 224.0.0.0/24 => 224.0.0.255 */
 303             if ((ipv4 & 0xffffff00) == 0xe0000000)
 304                 ipv4 =  0xe00000ff;
 305             else
 306             /* 239.255.0.0/16 => 239.255.255.255 */
 307             if ((ipv4 & 0xffff0000) == 0xefff0000)
 308                 ipv4 =  0xefffffff;
 309             else
 310             /* 239.192.0.0/14 => 239.195.255.255 */
 311             if ((ipv4 & 0xfffc0000) == 0xefc00000)
 312                 ipv4 =  0xefc3ffff;
 313             else
 314             if ((ipv4 & 0xff000000) == 0xef000000)
 315                 ipv4 = 0;
 316             else
 317             /* other addresses => 224.2.127.254 */
 318             {
 319                 /* SSM: 232.0.0.0/8 */
 320                 b_ssm = (ipv4 >> 24) == 232;
 321                 ipv4 = 0xe0027ffe;
 322             }
 323
 324             if( ipv4 == 0 )
 325             {
 326                 msg_Err( p_sap, "Out-of-scope multicast address "
 327                          "not supported by SAP" );
 328                 vlc_mutex_unlock( &p_sap->object_lock );
 329                 return VLC_EGENERIC;
 330             }
 331
 332             ((struct sockaddr_in *)&addr)->sin_addr.s_addr = htonl( ipv4 );
 333             break;
 334         }
 335
 336         default:
 337             vlc_mutex_unlock( &p_sap->object_lock );
 338             msg_Err( p_sap, "Address family %d not supported by SAP",
 339                      addr.ss_family );
 340             return VLC_EGENERIC;
 341     }
 342
 343     i = vlc_getnameinfo( (struct sockaddr *)&addr, addrlen,
 344                          psz_addr, sizeof( psz_addr ), NULL, NI_NUMERICHOST );
 345
 346     if( i )
 347     {
 348         vlc_mutex_unlock( &p_sap->object_lock );
 349         msg_Err( p_sap, "%s", vlc_gai_strerror( i ) );
 350         return VLC_EGENERIC;
 351     }
 352
 353     msg_Dbg( p_sap, "using SAP address: %s", psz_addr);
 354
 355     /* XXX: Check for dupes */
 356     p_sap_session = (sap_session_t*)malloc(sizeof(sap_session_t));
 357     p_sap_session->p_sd = p_session;
 358     p_sap_session->p_address = NULL;
 359
 360     /* Add the address to the buffer */
 361     for( i = 0; i < p_sap->i_addresses; i++)
 362     {
 363         if( !strcmp( psz_addr, p_sap->pp_addresses[i]->psz_address ) )
 364         {
 365             p_sap_session->p_address = p_sap->pp_addresses[i];
 366             break;
 367         }
 368     }
 369
 370     if( p_sap_session->p_address == NULL )
 371     {
 372         sap_address_t *p_address = (sap_address_t *)
 373                                     malloc( sizeof(sap_address_t) );
 374         if( !p_address )
 375         {
 376             vlc_mutex_unlock( &p_sap->object_lock );
 377             return VLC_ENOMEM;
 378         }
 379         p_address->psz_address = strdup( psz_addr );
 380         p_address->i_wfd = net_ConnectUDP( VLC_OBJECT(p_sap), psz_addr, SAP_PORT, 255 );
 381         if( p_address->i_wfd != -1 )
 382         {
 383             shutdown( p_address->i_wfd, SHUT_RD );
 384             p_address->origlen = sizeof (p_address->orig);
 385             getsockname (p_address->i_wfd, (struct sockaddr *)&p_address->orig,
 386                          &p_address->origlen);
 387         }
 388
 389         if( p_sap->b_control == VLC_TRUE )
 390         {
 391             p_address->i_rfd = net_ListenUDP1( (vlc_object_t*)p_sap, psz_addr, SAP_PORT );
 392             if( p_address->i_rfd != -1 )
 393                 shutdown( p_address->i_rfd, SHUT_WR );
 394             p_address->i_buff = 0;
 395             p_address->b_enabled = VLC_TRUE;
 396             p_address->b_ready = VLC_FALSE;
 397             p_address->i_limit = 10000; /* 10000 bps */
 398             p_address->t1 = 0;
 399         }
 400         else
 401         {
 402             p_address->b_enabled = VLC_TRUE;
 403             p_address->b_ready = VLC_TRUE;
 404             p_address->i_interval = config_GetInt( p_sap,"sap-interval");
 405             p_address->i_rfd = -1;
 406         }
 407
 408         if( p_address->i_wfd == -1 || (p_address->i_rfd == -1
 409                                         && p_sap->b_control ) )
 410         {
 411             msg_Warn( p_sap, "disabling address" );
 412             p_address->b_enabled = VLC_FALSE;
 413         }
 414
 415         INSERT_ELEM( p_sap->pp_addresses,
 416                      p_sap->i_addresses,
 417                      p_sap->i_addresses,
 418                      p_address );
 419         p_sap_session->p_address = p_address;
 420     }
 421
 422     memcpy (&p_session->orig, &p_sap_session->p_address->orig,
 423              p_session->origlen = p_sap_session->p_address->origlen);
 424
 425     size_t headsize = 20;
 426     switch (p_session->orig.ss_family)
 427     {
 428 #ifdef AF_INET6
 429         case AF_INET6:
 430             headsize += 16;
 431             break;
 432 #endif
 433         case AF_INET:
 434             headsize += 4;
 435             break;
 436         default:
 437             msg_Err( p_sap, "Address family %d not supported by SAP",
 438                      addr.ss_family );
 439             vlc_mutex_unlock( &p_sap->object_lock );
 440             return VLC_EGENERIC;
 441     }
 442
 443     /* If needed, build the SDP */
 444     assert( p_session->psz_sdp != NULL );
 445
 446     p_sap_session->i_last = 0;
 447     p_sap_session->i_length = headsize + strlen (p_session->psz_sdp);
 448     p_sap_session->psz_data = malloc (p_sap_session->i_length + 1);
 449     if (p_sap_session->psz_data == NULL)
 450     {
 451         free (p_session->psz_sdp);
 452         vlc_mutex_unlock( &p_sap->object_lock );
 453         return VLC_ENOMEM;
 454     }
 455
 456     /* Build the SAP Headers */
 457     uint8_t *psz_head = p_sap_session->psz_data;
 458
 459     /* SAPv1, not encrypted, not compressed */
 460     psz_head[0] = 0x20;
 461     psz_head[1] = 0x00; /* No authentification length */
 462
 463     i_hash = mdate();
 464     psz_head[2] = i_hash >> 8; /* Msg id hash */
 465     psz_head[3] = i_hash;      /* Msg id hash 2 */
 466
 467     headsize = 4;
 468     switch (p_session->orig.ss_family)
 469     {
 470 #ifdef AF_INET6
 471         case AF_INET6:
 472         {
 473             struct in6_addr *a6 =
 474                 &((struct sockaddr_in6 *)&p_session->orig)->sin6_addr;
 475             memcpy (psz_head + headsize, a6, 16);
 476             psz_head[0] |= 0x10; /* IPv6 flag */
 477             headsize += 16;
 478             break;
 479         }
 480 #endif
 481         case AF_INET:
 482         {
 483             uint32_t ipv4 =
 484                 (((struct sockaddr_in *)&p_session->orig)->sin_addr.s_addr);
 485             memcpy (psz_head + headsize, &ipv4, 4);
 486             headsize += 4;
 487             break;
 488         }
 489
 490     }
 491
 492     memcpy (psz_head + headsize, "application/sdp", 16);
 493     headsize += 16;
 494
 495     /* Build the final message */
 496     strcpy( (char *)psz_head + headsize, p_session->psz_sdp);
 497
 498     /* Enqueue the announce */
 499     INSERT_ELEM( p_sap->pp_sessions,
 500                  p_sap->i_sessions,
 501                  p_sap->i_sessions,
 502                  p_sap_session );
 503     msg_Dbg( p_sap,"%i addresses, %i sessions",
 504                    p_sap->i_addresses,p_sap->i_sessions);
 505
 506     vlc_mutex_unlock( &p_sap->object_lock );
 507
 508     return VLC_SUCCESS;
 509 }
 510
 511 /* Remove a SAP Announce */
 512 static int announce_SAPAnnounceDel( sap_handler_t *p_sap,
 513                              session_descriptor_t *p_session )
 514 {
 515     int i;
 516     vlc_mutex_lock( &p_sap->object_lock );
 517
 518     msg_Dbg( p_sap, "removing session %p from SAP", p_session);
 519
 520     /* Dequeue the announce */
 521     for( i = 0; i< p_sap->i_sessions; i++)
 522     {
 523         if( p_session == p_sap->pp_sessions[i]->p_sd )
 524         {
 525             sap_session_t *p_mysession = p_sap->pp_sessions[i];
 526             REMOVE_ELEM( p_sap->pp_sessions,
 527                          p_sap->i_sessions,
 528                          i );
 529
 530             free( p_mysession->psz_data );
 531             free( p_mysession );
 532             break;
 533         }
 534     }
 535
 536     /* XXX: Dequeue the address too if it is not used anymore
 537      * TODO: - address refcount
 538              - send a SAP deletion packet */
 539
 540     msg_Dbg( p_sap,"%i announcements remaining", p_sap->i_sessions );
 541
 542     vlc_mutex_unlock( &p_sap->object_lock );
 543
 544     return VLC_SUCCESS;
 545 }
 546
 547 static int announce_SendSAPAnnounce( sap_handler_t *p_sap,
 548                                      sap_session_t *p_session )
 549 {
 550     int i_ret;
 551
 552     /* This announce has never been sent yet */
 553     if( p_session->i_last == 0 )
 554     {
 555         p_session->i_next = mdate()+ p_session->p_address->i_interval*1000000;
 556         p_session->i_last = 1;
 557         return VLC_SUCCESS;
 558     }
 559
 560     if( p_session->i_next < mdate() )
 561     {
 562 #ifdef EXTRA_DEBUG
 563         msg_Dbg( p_sap, "sending announce");
 564 #endif
 565         i_ret = net_Write( p_sap, p_session->p_address->i_wfd, NULL,
 566                            p_session->psz_data,
 567                            p_session->i_length );
 568         if( i_ret != (int)p_session->i_length )
 569         {
 570             msg_Warn( p_sap, "SAP send failed on address %s (%i %i)",
 571                       p_session->p_address->psz_address,
 572                       i_ret, p_session->i_length );
 573         }
 574         p_session->i_last = p_session->i_next;
 575         p_session->i_next = p_session->i_last
 576                             + p_session->p_address->i_interval*1000000;
 577     }
 578     return VLC_SUCCESS;
 579 }
 580
 581 static int ComputeRate( sap_address_t *p_address )
 582 {
 583     uint8_t buffer[SAP_MAX_BUFFER];
 584     ssize_t i_tot = 0;
 585     mtime_t i_temp;
 586     int i_rate;
 587
 588     if( p_address->t1 == 0 )
 589     {
 590         p_address->t1 = mdate();
 591         return VLC_SUCCESS;
 592     }
 593     for (;;)
 594     {
 595         /* Might be too slow if we have huge data */
 596         ssize_t i_read = recv( p_address->i_rfd, buffer, SAP_MAX_BUFFER, 0 );
 597         if (i_read == -1)
 598             break;
 599         i_tot += i_read;
 600     }
 601
 602     i_temp = mdate();
 603
 604     /* We calculate the rate every 5 seconds */
 605     if( i_temp - p_address->t1 < 5000000 )
 606     {
 607         p_address->i_buff += i_tot;
 608         return VLC_SUCCESS;
 609     }
 610
 611     /* Bits/second */
 612     i_rate = (int)(8*1000000*((mtime_t)p_address->i_buff + (mtime_t)i_tot ) /
 613                         (i_temp - p_address->t1 ));
 614
 615     p_address->i_limit = 10000;
 616
 617     p_address->i_interval = ((1000*i_rate / p_address->i_limit) *
 618                             (MAX_INTERVAL - MIN_INTERVAL))/1000 + MIN_INTERVAL;
 619
 620     if( p_address->i_interval > MAX_INTERVAL || p_address->i_interval < 0 )
 621     {
 622         p_address->i_interval = MAX_INTERVAL;
 623     }
 624 #ifdef EXTRA_DEBUG
 625     msg_Dbg( p_sap,"%s:%i: rate=%i, interval = %i s",
 626              p_address->psz_address,SAP_PORT, i_rate, p_address->i_interval );
 627 #endif
 628
 629     p_address->b_ready = VLC_TRUE;
 630
 631     p_address->t1 = i_temp;
 632     p_address->i_buff = 0;
 633
 634     return VLC_SUCCESS;
 635 }