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
 124     if( !p_sap )
 125     {
 126         msg_Err( p_announce, "out of memory" );
 127         return NULL;
 128     }
 129
 130     vlc_mutex_init( p_sap, &p_sap->object_lock );
 131
 132     p_sap->pf_add = announce_SAPAnnounceAdd;
 133     p_sap->pf_del = announce_SAPAnnounceDel;
 134
 135     p_sap->i_sessions = 0;
 136     p_sap->i_addresses = 0;
 137     p_sap->i_current_session = 0;
 138
 139     p_sap->b_control = config_GetInt( p_sap, "sap-flow-control");
 140
 141     if( vlc_thread_create( p_sap, "sap handler", RunThread,
 142                        VLC_THREAD_PRIORITY_LOW, VLC_FALSE ) )
 143     {
 144         msg_Dbg( p_announce, "unable to spawn SAP handler thread");
 145         vlc_object_release( p_sap );
 146         return NULL;
 147     }
 148
 149     vlc_object_set_destructor( p_sap, announce_SAPHandlerDestructor );
 150
 151     msg_Dbg( p_announce, "thread created, %i sessions", p_sap->i_sessions);
 152
 153     return p_sap;
 154 }
 155
 156 static void announce_SAPHandlerDestructor( vlc_object_t * p_this )
 157 {
 158     sap_handler_t *p_sap = (sap_handler_t *)p_this;
 159     int i;
 160
 161     /* Free the remaining sessions */
 162     for( i = 0 ; i< p_sap->i_sessions ; i++)
 163     {
 164         sap_session_t *p_session = p_sap->pp_sessions[i];
 165         FREENULL( p_session->psz_data );
 166         REMOVE_ELEM( p_sap->pp_sessions, p_sap->i_sessions , i );
 167         FREENULL( p_session );
 168     }
 169
 170     /* Free the remaining addresses */
 171     for( i = 0 ; i< p_sap->i_addresses ; i++)
 172     {
 173         sap_address_t *p_address = p_sap->pp_addresses[i];
 174         FREENULL( p_address->psz_address );
 175         if( p_address->i_rfd > -1 )
 176         {
 177             net_Close( p_address->i_rfd );
 178         }
 179         if( p_address->i_wfd > -1 && p_sap->b_control )
 180         {
 181             net_Close( p_address->i_wfd );
 182         }
 183         REMOVE_ELEM( p_sap->pp_addresses, p_sap->i_addresses, i );
 184         FREENULL( p_address );
 185     }
 186 }
 187
 188 /**
 189  * main SAP handler thread
 190  * \param p_this the SAP Handler object
 191  * \return nothing
 192  */
 193 static void RunThread( vlc_object_t *p_this)
 194 {
 195     sap_handler_t *p_sap = (sap_handler_t*)p_this;
 196     sap_session_t *p_session;
 197
 198     while( !p_sap->b_die )
 199     {
 200         int i;
 201
 202         /* If needed, get the rate info */
 203         if( p_sap->b_control == VLC_TRUE )
 204         {
 205             for( i = 0 ; i< p_sap->i_addresses ; i++)
 206             {
 207                 if( p_sap->pp_addresses[i]->b_enabled == VLC_TRUE )
 208                 {
 209                     ComputeRate( p_sap->pp_addresses[i] );
 210                 }
 211             }
 212         }
 213
 214         /* Find the session to announce */
 215         vlc_mutex_lock( &p_sap->object_lock );
 216         if( p_sap->i_sessions > p_sap->i_current_session + 1)
 217         {
 218             p_sap->i_current_session++;
 219         }
 220         else if( p_sap->i_sessions > 0)
 221         {
 222             p_sap->i_current_session = 0;
 223         }
 224         else
 225         {
 226             vlc_mutex_unlock( &p_sap->object_lock );
 227             msleep( SAP_IDLE );
 228             continue;
 229         }
 230         p_session = p_sap->pp_sessions[p_sap->i_current_session];
 231         vlc_mutex_unlock( &p_sap->object_lock );
 232
 233         /* And announce it */
 234         if( p_session->p_address->b_enabled == VLC_TRUE &&
 235             p_session->p_address->b_ready == VLC_TRUE )
 236         {
 237             announce_SendSAPAnnounce( p_sap, p_session );
 238         }
 239
 240         msleep( SAP_IDLE );
 241     }
 242 }
 243
 244 /* Add a SAP announce */
 245 static int announce_SAPAnnounceAdd( sap_handler_t *p_sap,
 246                              session_descriptor_t *p_session )
 247 {
 248     int i;
 249     char psz_addr[NI_MAXNUMERICHOST];
 250     vlc_bool_t b_ipv6 = VLC_FALSE, b_ssm = VLC_FALSE;
 251     sap_session_t *p_sap_session;
 252     mtime_t i_hash;
 253     struct sockaddr_storage addr;
 254     socklen_t addrlen;
 255
 256     vlc_mutex_lock( &p_sap->object_lock );
 257     addrlen = p_session->addrlen;
 258     if ((addrlen == 0) || (addrlen > sizeof (addr)))
 259     {
 260         vlc_mutex_unlock( &p_sap->object_lock );
 261         msg_Err( p_sap, "No/invalid address specified for SAP announce" );
 262         return VLC_EGENERIC;
 263     }
 264
 265     /* Determine SAP multicast address automatically */
 266     memcpy (&addr, &p_session->addr, addrlen);
 267
 268     switch( p_session->addr.ss_family )
 269     {
 270 #if defined (HAVE_INET_PTON) || defined (WIN32)
 271         case AF_INET6:
 272         {
 273             /* See RFC3513 for list of valid IPv6 scopes */
 274             struct in6_addr *a6 = &((struct sockaddr_in6 *)&addr)->sin6_addr;
 275
 276             memcpy( a6->s6_addr + 2, "\x00\x00\x00\x00\x00\x00"
 277                    "\x00\x00\x00\x00\x00\x02\x7f\xfe", 14 );
 278             if( IN6_IS_ADDR_MULTICAST( a6 ) )
 279             {
 280                 /* SSM <=> ff3x::/32 */
 281                 b_ssm = (U32_AT (a6->s6_addr) & 0xfff0ffff) == 0xff300000;
 282
 283                 /* force flags to zero, preserve scope */
 284                 a6->s6_addr[1] &= 0xf;
 285             }
 286             else
 287                 /* Unicast IPv6 - assume global scope */
 288                 memcpy( a6->s6_addr, "\xff\x0e", 2 );
 289
 290             b_ipv6 = VLC_TRUE;
 291             break;
 292         }
 293 #endif
 294
 295         case AF_INET:
 296         {
 297             /* See RFC2365 for IPv4 scopes */
 298             uint32_t ipv4;
 299
 300             ipv4 = ntohl( ((struct sockaddr_in *)&addr)->sin_addr.s_addr );
 301             /* 224.0.0.0/24 => 224.0.0.255 */
 302             if ((ipv4 & 0xffffff00) == 0xe0000000)
 303                 ipv4 =  0xe00000ff;
 304             else
 305             /* 239.255.0.0/16 => 239.255.255.255 */
 306             if ((ipv4 & 0xffff0000) == 0xefff0000)
 307                 ipv4 =  0xefffffff;
 308             else
 309             /* 239.192.0.0/14 => 239.195.255.255 */
 310             if ((ipv4 & 0xfffc0000) == 0xefc00000)
 311                 ipv4 =  0xefc3ffff;
 312             else
 313             if ((ipv4 & 0xff000000) == 0xef000000)
 314                 ipv4 = 0;
 315             else
 316             /* other addresses => 224.2.127.254 */
 317             {
 318                 /* SSM: 232.0.0.0/8 */
 319                 b_ssm = (ipv4 >> 24) == 232;
 320                 ipv4 = 0xe0027ffe;
 321             }
 322
 323             if( ipv4 == 0 )
 324             {
 325                 msg_Err( p_sap, "Out-of-scope multicast address "
 326                          "not supported by SAP" );
 327                 vlc_mutex_unlock( &p_sap->object_lock );
 328                 return VLC_EGENERIC;
 329             }
 330
 331             ((struct sockaddr_in *)&addr)->sin_addr.s_addr = htonl( ipv4 );
 332             break;
 333         }
 334
 335         default:
 336             vlc_mutex_unlock( &p_sap->object_lock );
 337             msg_Err( p_sap, "Address family %d not supported by SAP",
 338                      addr.ss_family );
 339             return VLC_EGENERIC;
 340     }
 341
 342     i = vlc_getnameinfo( (struct sockaddr *)&addr, addrlen,
 343                          psz_addr, sizeof( psz_addr ), NULL, NI_NUMERICHOST );
 344
 345     if( i )
 346     {
 347         vlc_mutex_unlock( &p_sap->object_lock );
 348         msg_Err( p_sap, "%s", vlc_gai_strerror( i ) );
 349         return VLC_EGENERIC;
 350     }
 351
 352     msg_Dbg( p_sap, "using SAP address: %s", psz_addr);
 353
 354     /* XXX: Check for dupes */
 355     p_sap_session = (sap_session_t*)malloc(sizeof(sap_session_t));
 356     p_sap_session->p_sd = p_session;
 357     p_sap_session->p_address = NULL;
 358
 359     /* Add the address to the buffer */
 360     for( i = 0; i < p_sap->i_addresses; i++)
 361     {
 362         if( !strcmp( psz_addr, p_sap->pp_addresses[i]->psz_address ) )
 363         {
 364             p_sap_session->p_address = p_sap->pp_addresses[i];
 365             break;
 366         }
 367     }
 368
 369     if( p_sap_session->p_address == NULL )
 370     {
 371         sap_address_t *p_address = (sap_address_t *)
 372                                     malloc( sizeof(sap_address_t) );
 373         if( !p_address )
 374         {
 375             vlc_mutex_unlock( &p_sap->object_lock );
 376             return VLC_ENOMEM;
 377         }
 378         p_address->psz_address = strdup( psz_addr );
 379         p_address->i_wfd = net_ConnectUDP( VLC_OBJECT(p_sap), psz_addr, SAP_PORT, 255 );
 380         if( p_address->i_wfd != -1 )
 381         {
 382             shutdown( p_address->i_wfd, SHUT_RD );
 383             p_address->origlen = sizeof (p_address->orig);
 384             getsockname (p_address->i_wfd, (struct sockaddr *)&p_address->orig,
 385                          &p_address->origlen);
 386         }
 387
 388         if( p_sap->b_control == VLC_TRUE )
 389         {
 390             p_address->i_rfd = net_ListenUDP1( (vlc_object_t*)p_sap, psz_addr, SAP_PORT );
 391             if( p_address->i_rfd != -1 )
 392                 shutdown( p_address->i_rfd, SHUT_WR );
 393             p_address->i_buff = 0;
 394             p_address->b_enabled = VLC_TRUE;
 395             p_address->b_ready = VLC_FALSE;
 396             p_address->i_limit = 10000; /* 10000 bps */
 397             p_address->t1 = 0;
 398         }
 399         else
 400         {
 401             p_address->b_enabled = VLC_TRUE;
 402             p_address->b_ready = VLC_TRUE;
 403             p_address->i_interval = config_GetInt( p_sap,"sap-interval");
 404             p_address->i_rfd = -1;
 405         }
 406
 407         if( p_address->i_wfd == -1 || (p_address->i_rfd == -1
 408                                         && p_sap->b_control ) )
 409         {
 410             msg_Warn( p_sap, "disabling address" );
 411             p_address->b_enabled = VLC_FALSE;
 412         }
 413
 414         INSERT_ELEM( p_sap->pp_addresses,
 415                      p_sap->i_addresses,
 416                      p_sap->i_addresses,
 417                      p_address );
 418         p_sap_session->p_address = p_address;
 419     }
 420
 421     memcpy (&p_session->orig, &p_sap_session->p_address->orig,
 422              p_session->origlen = p_sap_session->p_address->origlen);
 423
 424     size_t headsize = 20;
 425     switch (p_session->orig.ss_family)
 426     {
 427 #ifdef AF_INET6
 428         case AF_INET6:
 429             headsize += 16;
 430             break;
 431 #endif
 432         case AF_INET:
 433             headsize += 4;
 434             break;
 435         default:
 436             msg_Err( p_sap, "Address family %d not supported by SAP",
 437                      addr.ss_family );
 438             vlc_mutex_unlock( &p_sap->object_lock );
 439             return VLC_EGENERIC;
 440     }
 441
 442     /* If needed, build the SDP */
 443     assert( p_session->psz_sdp != NULL );
 444
 445     p_sap_session->i_last = 0;
 446     p_sap_session->i_length = headsize + strlen (p_session->psz_sdp);
 447     p_sap_session->psz_data = malloc (p_sap_session->i_length + 1);
 448     if (p_sap_session->psz_data == NULL)
 449     {
 450         free (p_session->psz_sdp);
 451         vlc_mutex_unlock( &p_sap->object_lock );
 452         return VLC_ENOMEM;
 453     }
 454
 455     /* Build the SAP Headers */
 456     uint8_t *psz_head = p_sap_session->psz_data;
 457
 458     /* SAPv1, not encrypted, not compressed */
 459     psz_head[0] = 0x20;
 460     psz_head[1] = 0x00; /* No authentification length */
 461
 462     i_hash = mdate();
 463     psz_head[2] = i_hash >> 8; /* Msg id hash */
 464     psz_head[3] = i_hash;      /* Msg id hash 2 */
 465
 466     headsize = 4;
 467     switch (p_session->orig.ss_family)
 468     {
 469 #ifdef AF_INET6
 470         case AF_INET6:
 471         {
 472             struct in6_addr *a6 =
 473                 &((struct sockaddr_in6 *)&p_session->orig)->sin6_addr;
 474             memcpy (psz_head + headsize, a6, 16);
 475             psz_head[0] |= 0x10; /* IPv6 flag */
 476             headsize += 16;
 477             break;
 478         }
 479 #endif
 480         case AF_INET:
 481         {
 482             uint32_t ipv4 =
 483                 (((struct sockaddr_in *)&p_session->orig)->sin_addr.s_addr);
 484             memcpy (psz_head + headsize, &ipv4, 4);
 485             headsize += 4;
 486             break;
 487         }
 488
 489     }
 490
 491     memcpy (psz_head + headsize, "application/sdp", 16);
 492     headsize += 16;
 493
 494     /* Build the final message */
 495     strcpy( (char *)psz_head + headsize, p_session->psz_sdp);
 496
 497     /* Enqueue the announce */
 498     INSERT_ELEM( p_sap->pp_sessions,
 499                  p_sap->i_sessions,
 500                  p_sap->i_sessions,
 501                  p_sap_session );
 502     msg_Dbg( p_sap,"%i addresses, %i sessions",
 503                    p_sap->i_addresses,p_sap->i_sessions);
 504
 505     vlc_mutex_unlock( &p_sap->object_lock );
 506
 507     return VLC_SUCCESS;
 508 }
 509
 510 /* Remove a SAP Announce */
 511 static int announce_SAPAnnounceDel( sap_handler_t *p_sap,
 512                              session_descriptor_t *p_session )
 513 {
 514     int i;
 515     vlc_mutex_lock( &p_sap->object_lock );
 516
 517     msg_Dbg( p_sap, "removing session %p from SAP", p_session);
 518
 519     /* Dequeue the announce */
 520     for( i = 0; i< p_sap->i_sessions; i++)
 521     {
 522         if( p_session == p_sap->pp_sessions[i]->p_sd )
 523         {
 524             sap_session_t *p_mysession = p_sap->pp_sessions[i];
 525             REMOVE_ELEM( p_sap->pp_sessions,
 526                          p_sap->i_sessions,
 527                          i );
 528
 529             free( p_mysession->psz_data );
 530             free( p_mysession );
 531             break;
 532         }
 533     }
 534
 535     /* XXX: Dequeue the address too if it is not used anymore
 536      * TODO: - address refcount
 537              - send a SAP deletion packet */
 538
 539     msg_Dbg( p_sap,"%i announcements remaining", p_sap->i_sessions );
 540
 541     vlc_mutex_unlock( &p_sap->object_lock );
 542
 543     return VLC_SUCCESS;
 544 }
 545
 546 static int announce_SendSAPAnnounce( sap_handler_t *p_sap,
 547                                      sap_session_t *p_session )
 548 {
 549     int i_ret;
 550
 551     /* This announce has never been sent yet */
 552     if( p_session->i_last == 0 )
 553     {
 554         p_session->i_next = mdate()+ p_session->p_address->i_interval*1000000;
 555         p_session->i_last = 1;
 556         return VLC_SUCCESS;
 557     }
 558
 559     if( p_session->i_next < mdate() )
 560     {
 561 #ifdef EXTRA_DEBUG
 562         msg_Dbg( p_sap, "sending announce");
 563 #endif
 564         i_ret = net_Write( p_sap, p_session->p_address->i_wfd, NULL,
 565                            p_session->psz_data,
 566                            p_session->i_length );
 567         if( i_ret != (int)p_session->i_length )
 568         {
 569             msg_Warn( p_sap, "SAP send failed on address %s (%i %i)",
 570                       p_session->p_address->psz_address,
 571                       i_ret, p_session->i_length );
 572         }
 573         p_session->i_last = p_session->i_next;
 574         p_session->i_next = p_session->i_last
 575                             + p_session->p_address->i_interval*1000000;
 576     }
 577     return VLC_SUCCESS;
 578 }
 579
 580 static int ComputeRate( sap_address_t *p_address )
 581 {
 582     uint8_t buffer[SAP_MAX_BUFFER];
 583     ssize_t i_tot = 0;
 584     mtime_t i_temp;
 585     int i_rate;
 586
 587     if( p_address->t1 == 0 )
 588     {
 589         p_address->t1 = mdate();
 590         return VLC_SUCCESS;
 591     }
 592     for (;;)
 593     {
 594         /* Might be too slow if we have huge data */
 595         ssize_t i_read = recv( p_address->i_rfd, buffer, SAP_MAX_BUFFER, 0 );
 596         if (i_read == -1)
 597             break;
 598         i_tot += i_read;
 599     }
 600
 601     i_temp = mdate();
 602
 603     /* We calculate the rate every 5 seconds */
 604     if( i_temp - p_address->t1 < 5000000 )
 605     {
 606         p_address->i_buff += i_tot;
 607         return VLC_SUCCESS;
 608     }
 609
 610     /* Bits/second */
 611     i_rate = (int)(8*1000000*((mtime_t)p_address->i_buff + (mtime_t)i_tot ) /
 612                         (i_temp - p_address->t1 ));
 613
 614     p_address->i_limit = 10000;
 615
 616     p_address->i_interval = ((1000*i_rate / p_address->i_limit) *
 617                             (MAX_INTERVAL - MIN_INTERVAL))/1000 + MIN_INTERVAL;
 618
 619     if( p_address->i_interval > MAX_INTERVAL || p_address->i_interval < 0 )
 620     {
 621         p_address->i_interval = MAX_INTERVAL;
 622     }
 623 #ifdef EXTRA_DEBUG
 624     msg_Dbg( p_sap,"%s:%i: rate=%i, interval = %i s",
 625              p_address->psz_address,SAP_PORT, i_rate, p_address->i_interval );
 626 #endif
 627
 628     p_address->b_ready = VLC_TRUE;
 629
 630     p_address->t1 = i_temp;
 631     p_address->i_buff = 0;
 632
 633     return VLC_SUCCESS;
 634 }