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