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 #include "libvlc.h"
  47
  48 /* SAP is always on that port */
  49 #define SAP_PORT 9875
  50
  51 #define DEFAULT_PORT "1234"
  52
  53 #undef EXTRA_DEBUG
  54
  55 /* SAP Specific structures */
  56
  57 /* 100ms */
  58 #define SAP_IDLE ((mtime_t)(0.100*CLOCK_FREQ))
  59 #define SAP_MAX_BUFFER 65534
  60 #define MIN_INTERVAL 2
  61 #define MAX_INTERVAL 300
  62
  63 /* A SAP announce address. For each of these, we run the
  64  * control flow algorithm */
  65 struct sap_address_t
  66 {
  67     char *psz_address;
  68     struct sockaddr_storage orig;
  69     socklen_t origlen;
  70     int i_rfd; /* Read socket */
  71     int i_wfd; /* Write socket */
  72
  73     /* Used for flow control */
  74     mtime_t t1;
  75     vlc_bool_t b_enabled;
  76     vlc_bool_t b_ready;
  77     int i_interval;
  78     int i_buff;
  79     int i_limit;
  80 };
  81
  82 /* A SAP session descriptor, enqueued in the SAP handler queue */
  83 struct sap_session_t {
  84     uint8_t       *psz_data;
  85     unsigned      i_length;
  86     sap_address_t *p_address;
  87     session_descriptor_t *p_sd;
  88
  89     /* Last and next send */
  90     mtime_t        i_last;
  91     mtime_t        i_next;
  92 };
  93
  94 /*****************************************************************************
  95  * Local prototypes
  96  *****************************************************************************/
  97 static void RunThread( vlc_object_t *p_this);
  98 static int ComputeRate( sap_address_t *p_address );
  99
 100 static int announce_SendSAPAnnounce( sap_handler_t *p_sap,
 101                                      sap_session_t *p_session );
 102
 103
 104 static int announce_SAPAnnounceAdd( sap_handler_t *p_sap,
 105                              session_descriptor_t *p_session );
 106
 107 static int announce_SAPAnnounceDel( sap_handler_t *p_sap,
 108                              session_descriptor_t *p_session );
 109
 110 static void announce_SAPHandlerDestructor( vlc_object_t *p_this );
 111
 112
 113 /**
 114  * Create the SAP handler
 115  *
 116  * \param p_announce the parent announce_handler
 117  * \return the newly created SAP handler or NULL on error
 118  */
 119 sap_handler_t *announce_SAPHandlerCreate( announce_handler_t *p_announce )
 120 {
 121     sap_handler_t *p_sap;
 122
 123     p_sap = vlc_custom_create( VLC_OBJECT(p_announce), sizeof( sap_handler_t ),
 124                                VLC_OBJECT_ANNOUNCE, "announce" );
 125     if( !p_sap )
 126     {
 127         msg_Err( p_announce, "out of memory" );
 128         return NULL;
 129     }
 130
 131     p_sap->psz_object_name = "sap announcer";
 132
 133     vlc_mutex_init( p_sap, &p_sap->object_lock );
 134
 135     p_sap->pf_add = announce_SAPAnnounceAdd;
 136     p_sap->pf_del = announce_SAPAnnounceDel;
 137
 138     p_sap->i_sessions = 0;
 139     p_sap->i_addresses = 0;
 140     p_sap->i_current_session = 0;
 141
 142     p_sap->b_control = config_GetInt( p_sap, "sap-flow-control");
 143
 144     if( vlc_thread_create( p_sap, "sap handler", RunThread,
 145                        VLC_THREAD_PRIORITY_LOW, VLC_FALSE ) )
 146     {
 147         msg_Dbg( p_announce, "unable to spawn SAP handler thread");
 148         vlc_object_release( p_sap );
 149         return NULL;
 150     }
 151
 152     vlc_object_set_destructor( p_sap, announce_SAPHandlerDestructor );
 153
 154     msg_Dbg( p_announce, "thread created, %i sessions", p_sap->i_sessions);
 155
 156     return p_sap;
 157 }
 158
 159 static void announce_SAPHandlerDestructor( vlc_object_t * p_this )
 160 {
 161     sap_handler_t *p_sap = (sap_handler_t *)p_this;
 162     int i;
 163
 164     /* Free the remaining sessions */
 165     for( i = 0 ; i< p_sap->i_sessions ; i++)
 166     {
 167         sap_session_t *p_session = p_sap->pp_sessions[i];
 168         FREENULL( p_session->psz_data );
 169         REMOVE_ELEM( p_sap->pp_sessions, p_sap->i_sessions , i );
 170         FREENULL( p_session );
 171     }
 172
 173     /* Free the remaining addresses */
 174     for( i = 0 ; i< p_sap->i_addresses ; i++)
 175     {
 176         sap_address_t *p_address = p_sap->pp_addresses[i];
 177         FREENULL( p_address->psz_address );
 178         if( p_address->i_rfd > -1 )
 179         {
 180             net_Close( p_address->i_rfd );
 181         }
 182         if( p_address->i_wfd > -1 && p_sap->b_control )
 183         {
 184             net_Close( p_address->i_wfd );
 185         }
 186         REMOVE_ELEM( p_sap->pp_addresses, p_sap->i_addresses, i );
 187         FREENULL( p_address );
 188     }
 189 }
 190
 191 /**
 192  * main SAP handler thread
 193  * \param p_this the SAP Handler object
 194  * \return nothing
 195  */
 196 static void RunThread( vlc_object_t *p_this)
 197 {
 198     sap_handler_t *p_sap = (sap_handler_t*)p_this;
 199     sap_session_t *p_session;
 200
 201     while( !p_sap->b_die )
 202     {
 203         int i;
 204
 205         /* If needed, get the rate info */
 206         if( p_sap->b_control == VLC_TRUE )
 207         {
 208             for( i = 0 ; i< p_sap->i_addresses ; i++)
 209             {
 210                 if( p_sap->pp_addresses[i]->b_enabled == VLC_TRUE )
 211                 {
 212                     ComputeRate( p_sap->pp_addresses[i] );
 213                 }
 214             }
 215         }
 216
 217         /* Find the session to announce */
 218         vlc_mutex_lock( &p_sap->object_lock );
 219         if( p_sap->i_sessions > p_sap->i_current_session + 1)
 220         {
 221             p_sap->i_current_session++;
 222         }
 223         else if( p_sap->i_sessions > 0)
 224         {
 225             p_sap->i_current_session = 0;
 226         }
 227         else
 228         {
 229             vlc_mutex_unlock( &p_sap->object_lock );
 230             msleep( SAP_IDLE );
 231             continue;
 232         }
 233         p_session = p_sap->pp_sessions[p_sap->i_current_session];
 234         vlc_mutex_unlock( &p_sap->object_lock );
 235
 236         /* And announce it */
 237         if( p_session->p_address->b_enabled == VLC_TRUE &&
 238             p_session->p_address->b_ready == VLC_TRUE )
 239         {
 240             announce_SendSAPAnnounce( p_sap, p_session );
 241         }
 242
 243         msleep( SAP_IDLE );
 244     }
 245 }
 246
 247 /* Add a SAP announce */
 248 static int announce_SAPAnnounceAdd( sap_handler_t *p_sap,
 249                              session_descriptor_t *p_session )
 250 {
 251     int i;
 252     char psz_addr[NI_MAXNUMERICHOST];
 253     vlc_bool_t b_ipv6 = VLC_FALSE, b_ssm = VLC_FALSE;
 254     sap_session_t *p_sap_session;
 255     mtime_t i_hash;
 256     struct sockaddr_storage addr;
 257     socklen_t addrlen;
 258
 259     vlc_mutex_lock( &p_sap->object_lock );
 260     addrlen = p_session->addrlen;
 261     if ((addrlen == 0) || (addrlen > sizeof (addr)))
 262     {
 263         vlc_mutex_unlock( &p_sap->object_lock );
 264         msg_Err( p_sap, "No/invalid address specified for SAP announce" );
 265         return VLC_EGENERIC;
 266     }
 267
 268     /* Determine SAP multicast address automatically */
 269     memcpy (&addr, &p_session->addr, addrlen);
 270
 271     switch( p_session->addr.ss_family )
 272     {
 273 #if defined (HAVE_INET_PTON) || defined (WIN32)
 274         case AF_INET6:
 275         {
 276             /* See RFC3513 for list of valid IPv6 scopes */
 277             struct in6_addr *a6 = &((struct sockaddr_in6 *)&addr)->sin6_addr;
 278
 279             memcpy( a6->s6_addr + 2, "\x00\x00\x00\x00\x00\x00"
 280                    "\x00\x00\x00\x00\x00\x02\x7f\xfe", 14 );
 281             if( IN6_IS_ADDR_MULTICAST( a6 ) )
 282             {
 283                 /* SSM <=> ff3x::/32 */
 284                 b_ssm = (U32_AT (a6->s6_addr) & 0xfff0ffff) == 0xff300000;
 285
 286                 /* force flags to zero, preserve scope */
 287                 a6->s6_addr[1] &= 0xf;
 288             }
 289             else
 290                 /* Unicast IPv6 - assume global scope */
 291                 memcpy( a6->s6_addr, "\xff\x0e", 2 );
 292
 293             b_ipv6 = VLC_TRUE;
 294             break;
 295         }
 296 #endif
 297
 298         case AF_INET:
 299         {
 300             /* See RFC2365 for IPv4 scopes */
 301             uint32_t ipv4;
 302
 303             ipv4 = ntohl( ((struct sockaddr_in *)&addr)->sin_addr.s_addr );
 304             /* 224.0.0.0/24 => 224.0.0.255 */
 305             if ((ipv4 & 0xffffff00) == 0xe0000000)
 306                 ipv4 =  0xe00000ff;
 307             else
 308             /* 239.255.0.0/16 => 239.255.255.255 */
 309             if ((ipv4 & 0xffff0000) == 0xefff0000)
 310                 ipv4 =  0xefffffff;
 311             else
 312             /* 239.192.0.0/14 => 239.195.255.255 */
 313             if ((ipv4 & 0xfffc0000) == 0xefc00000)
 314                 ipv4 =  0xefc3ffff;
 315             else
 316             if ((ipv4 & 0xff000000) == 0xef000000)
 317                 ipv4 = 0;
 318             else
 319             /* other addresses => 224.2.127.254 */
 320             {
 321                 /* SSM: 232.0.0.0/8 */
 322                 b_ssm = (ipv4 >> 24) == 232;
 323                 ipv4 = 0xe0027ffe;
 324             }
 325
 326             if( ipv4 == 0 )
 327             {
 328                 msg_Err( p_sap, "Out-of-scope multicast address "
 329                          "not supported by SAP" );
 330                 vlc_mutex_unlock( &p_sap->object_lock );
 331                 return VLC_EGENERIC;
 332             }
 333
 334             ((struct sockaddr_in *)&addr)->sin_addr.s_addr = htonl( ipv4 );
 335             break;
 336         }
 337
 338         default:
 339             vlc_mutex_unlock( &p_sap->object_lock );
 340             msg_Err( p_sap, "Address family %d not supported by SAP",
 341                      addr.ss_family );
 342             return VLC_EGENERIC;
 343     }
 344
 345     i = vlc_getnameinfo( (struct sockaddr *)&addr, addrlen,
 346                          psz_addr, sizeof( psz_addr ), NULL, NI_NUMERICHOST );
 347
 348     if( i )
 349     {
 350         vlc_mutex_unlock( &p_sap->object_lock );
 351         msg_Err( p_sap, "%s", vlc_gai_strerror( i ) );
 352         return VLC_EGENERIC;
 353     }
 354
 355     msg_Dbg( p_sap, "using SAP address: %s", psz_addr);
 356
 357     /* XXX: Check for dupes */
 358     p_sap_session = (sap_session_t*)malloc(sizeof(sap_session_t));
 359     p_sap_session->p_sd = p_session;
 360     p_sap_session->p_address = NULL;
 361
 362     /* Add the address to the buffer */
 363     for( i = 0; i < p_sap->i_addresses; i++)
 364     {
 365         if( !strcmp( psz_addr, p_sap->pp_addresses[i]->psz_address ) )
 366         {
 367             p_sap_session->p_address = p_sap->pp_addresses[i];
 368             break;
 369         }
 370     }
 371
 372     if( p_sap_session->p_address == NULL )
 373     {
 374         sap_address_t *p_address = (sap_address_t *)
 375                                     malloc( sizeof(sap_address_t) );
 376         if( !p_address )
 377         {
 378             vlc_mutex_unlock( &p_sap->object_lock );
 379             return VLC_ENOMEM;
 380         }
 381         p_address->psz_address = strdup( psz_addr );
 382         p_address->i_wfd = net_ConnectUDP( VLC_OBJECT(p_sap), psz_addr, SAP_PORT, 255 );
 383         if( p_address->i_wfd != -1 )
 384         {
 385             shutdown( p_address->i_wfd, SHUT_RD );
 386             p_address->origlen = sizeof (p_address->orig);
 387             getsockname (p_address->i_wfd, (struct sockaddr *)&p_address->orig,
 388                          &p_address->origlen);
 389         }
 390
 391         if( p_sap->b_control == VLC_TRUE )
 392         {
 393             p_address->i_rfd = net_ListenUDP1( (vlc_object_t*)p_sap, psz_addr, SAP_PORT );
 394             if( p_address->i_rfd != -1 )
 395                 shutdown( p_address->i_rfd, SHUT_WR );
 396             p_address->i_buff = 0;
 397             p_address->b_enabled = VLC_TRUE;
 398             p_address->b_ready = VLC_FALSE;
 399             p_address->i_limit = 10000; /* 10000 bps */
 400             p_address->t1 = 0;
 401         }
 402         else
 403         {
 404             p_address->b_enabled = VLC_TRUE;
 405             p_address->b_ready = VLC_TRUE;
 406             p_address->i_interval = config_GetInt( p_sap,"sap-interval");
 407             p_address->i_rfd = -1;
 408         }
 409
 410         if( p_address->i_wfd == -1 || (p_address->i_rfd == -1
 411                                         && p_sap->b_control ) )
 412         {
 413             msg_Warn( p_sap, "disabling address" );
 414             p_address->b_enabled = VLC_FALSE;
 415         }
 416
 417         INSERT_ELEM( p_sap->pp_addresses,
 418                      p_sap->i_addresses,
 419                      p_sap->i_addresses,
 420                      p_address );
 421         p_sap_session->p_address = p_address;
 422     }
 423
 424     memcpy (&p_session->orig, &p_sap_session->p_address->orig,
 425              p_session->origlen = p_sap_session->p_address->origlen);
 426
 427     size_t headsize = 20;
 428     switch (p_session->orig.ss_family)
 429     {
 430 #ifdef AF_INET6
 431         case AF_INET6:
 432             headsize += 16;
 433             break;
 434 #endif
 435         case AF_INET:
 436             headsize += 4;
 437             break;
 438         default:
 439             msg_Err( p_sap, "Address family %d not supported by SAP",
 440                      addr.ss_family );
 441             vlc_mutex_unlock( &p_sap->object_lock );
 442             return VLC_EGENERIC;
 443     }
 444
 445     /* If needed, build the SDP */
 446     assert( p_session->psz_sdp != NULL );
 447
 448     p_sap_session->i_last = 0;
 449     p_sap_session->i_length = headsize + strlen (p_session->psz_sdp);
 450     p_sap_session->psz_data = malloc (p_sap_session->i_length + 1);
 451     if (p_sap_session->psz_data == NULL)
 452     {
 453         free (p_session->psz_sdp);
 454         vlc_mutex_unlock( &p_sap->object_lock );
 455         return VLC_ENOMEM;
 456     }
 457
 458     /* Build the SAP Headers */
 459     uint8_t *psz_head = p_sap_session->psz_data;
 460
 461     /* SAPv1, not encrypted, not compressed */
 462     psz_head[0] = 0x20;
 463     psz_head[1] = 0x00; /* No authentification length */
 464
 465     i_hash = mdate();
 466     psz_head[2] = i_hash >> 8; /* Msg id hash */
 467     psz_head[3] = i_hash;      /* Msg id hash 2 */
 468
 469     headsize = 4;
 470     switch (p_session->orig.ss_family)
 471     {
 472 #ifdef AF_INET6
 473         case AF_INET6:
 474         {
 475             struct in6_addr *a6 =
 476                 &((struct sockaddr_in6 *)&p_session->orig)->sin6_addr;
 477             memcpy (psz_head + headsize, a6, 16);
 478             psz_head[0] |= 0x10; /* IPv6 flag */
 479             headsize += 16;
 480             break;
 481         }
 482 #endif
 483         case AF_INET:
 484         {
 485             uint32_t ipv4 =
 486                 (((struct sockaddr_in *)&p_session->orig)->sin_addr.s_addr);
 487             memcpy (psz_head + headsize, &ipv4, 4);
 488             headsize += 4;
 489             break;
 490         }
 491
 492     }
 493
 494     memcpy (psz_head + headsize, "application/sdp", 16);
 495     headsize += 16;
 496
 497     /* Build the final message */
 498     strcpy( (char *)psz_head + headsize, p_session->psz_sdp);
 499
 500     /* Enqueue the announce */
 501     INSERT_ELEM( p_sap->pp_sessions,
 502                  p_sap->i_sessions,
 503                  p_sap->i_sessions,
 504                  p_sap_session );
 505     msg_Dbg( p_sap,"%i addresses, %i sessions",
 506                    p_sap->i_addresses,p_sap->i_sessions);
 507
 508     vlc_mutex_unlock( &p_sap->object_lock );
 509
 510     return VLC_SUCCESS;
 511 }
 512
 513 /* Remove a SAP Announce */
 514 static int announce_SAPAnnounceDel( sap_handler_t *p_sap,
 515                              session_descriptor_t *p_session )
 516 {
 517     int i;
 518     vlc_mutex_lock( &p_sap->object_lock );
 519
 520     msg_Dbg( p_sap, "removing session %p from SAP", p_session);
 521
 522     /* Dequeue the announce */
 523     for( i = 0; i< p_sap->i_sessions; i++)
 524     {
 525         if( p_session == p_sap->pp_sessions[i]->p_sd )
 526         {
 527             sap_session_t *p_mysession = p_sap->pp_sessions[i];
 528             REMOVE_ELEM( p_sap->pp_sessions,
 529                          p_sap->i_sessions,
 530                          i );
 531
 532             free( p_mysession->psz_data );
 533             free( p_mysession );
 534             break;
 535         }
 536     }
 537
 538     /* XXX: Dequeue the address too if it is not used anymore
 539      * TODO: - address refcount
 540              - send a SAP deletion packet */
 541
 542     msg_Dbg( p_sap,"%i announcements remaining", p_sap->i_sessions );
 543
 544     vlc_mutex_unlock( &p_sap->object_lock );
 545
 546     return VLC_SUCCESS;
 547 }
 548
 549 static int announce_SendSAPAnnounce( sap_handler_t *p_sap,
 550                                      sap_session_t *p_session )
 551 {
 552     int i_ret;
 553
 554     /* This announce has never been sent yet */
 555     if( p_session->i_last == 0 )
 556     {
 557         p_session->i_next = mdate()+ p_session->p_address->i_interval*1000000;
 558         p_session->i_last = 1;
 559         return VLC_SUCCESS;
 560     }
 561
 562     if( p_session->i_next < mdate() )
 563     {
 564 #ifdef EXTRA_DEBUG
 565         msg_Dbg( p_sap, "sending announce");
 566 #endif
 567         i_ret = net_Write( p_sap, p_session->p_address->i_wfd, NULL,
 568                            p_session->psz_data,
 569                            p_session->i_length );
 570         if( i_ret != (int)p_session->i_length )
 571         {
 572             msg_Warn( p_sap, "SAP send failed on address %s (%i %i)",
 573                       p_session->p_address->psz_address,
 574                       i_ret, p_session->i_length );
 575         }
 576         p_session->i_last = p_session->i_next;
 577         p_session->i_next = p_session->i_last
 578                             + p_session->p_address->i_interval*1000000;
 579     }
 580     return VLC_SUCCESS;
 581 }
 582
 583 static int ComputeRate( sap_address_t *p_address )
 584 {
 585     uint8_t buffer[SAP_MAX_BUFFER];
 586     ssize_t i_tot = 0;
 587     mtime_t i_temp;
 588     int i_rate;
 589
 590     if( p_address->t1 == 0 )
 591     {
 592         p_address->t1 = mdate();
 593         return VLC_SUCCESS;
 594     }
 595     for (;;)
 596     {
 597         /* Might be too slow if we have huge data */
 598         ssize_t i_read = recv( p_address->i_rfd, buffer, SAP_MAX_BUFFER, 0 );
 599         if (i_read == -1)
 600             break;
 601         i_tot += i_read;
 602     }
 603
 604     i_temp = mdate();
 605
 606     /* We calculate the rate every 5 seconds */
 607     if( i_temp - p_address->t1 < 5000000 )
 608     {
 609         p_address->i_buff += i_tot;
 610         return VLC_SUCCESS;
 611     }
 612
 613     /* Bits/second */
 614     i_rate = (int)(8*1000000*((mtime_t)p_address->i_buff + (mtime_t)i_tot ) /
 615                         (i_temp - p_address->t1 ));
 616
 617     p_address->i_limit = 10000;
 618
 619     p_address->i_interval = ((1000*i_rate / p_address->i_limit) *
 620                             (MAX_INTERVAL - MIN_INTERVAL))/1000 + MIN_INTERVAL;
 621
 622     if( p_address->i_interval > MAX_INTERVAL || p_address->i_interval < 0 )
 623     {
 624         p_address->i_interval = MAX_INTERVAL;
 625     }
 626 #ifdef EXTRA_DEBUG
 627     msg_Dbg( p_sap,"%s:%i: rate=%i, interval = %i s",
 628              p_address->psz_address,SAP_PORT, i_rate, p_address->i_interval );
 629 #endif
 630
 631     p_address->b_ready = VLC_TRUE;
 632
 633     p_address->t1 = i_temp;
 634     p_address->i_buff = 0;
 635
 636     return VLC_SUCCESS;
 637 }