modules/services_discovery/sap.c

   1 /*****************************************************************************
   2  * sap.c :  SAP interface module
   3  *****************************************************************************
   4  * Copyright (C) 2004-2005 the VideoLAN team
   5  * Copyright © 2007 Rémi Denis-Courmont
   6  * $Id$
   7  *
   8  * Authors: Clément Stenac <zorglub@videolan.org>
   9  *          Rémi Denis-Courmont
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; either version 2 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  24  *****************************************************************************/
  25
  26 /*****************************************************************************
  27  * Includes
  28  *****************************************************************************/
  29 #ifdef HAVE_CONFIG_H
  30 # include "config.h"
  31 #endif
  32
  33 #include <vlc_common.h>
  34 #include <vlc_plugin.h>
  35 #include <assert.h>
  36
  37 #include <vlc_demux.h>
  38 #include <vlc_services_discovery.h>
  39
  40 #include <vlc_network.h>
  41 #include <vlc_charset.h>
  42
  43 #include <errno.h>
  44 #include <unistd.h>
  45 #ifdef HAVE_ARPA_INET_H
  46 # include <arpa/inet.h>
  47 #endif
  48 #ifdef HAVE_POLL
  49 # include <poll.h>
  50 #endif
  51
  52 #ifdef HAVE_ZLIB_H
  53 #   include <zlib.h>
  54 #endif
  55
  56 #ifndef _WIN32
  57 #   include <net/if.h>
  58 #endif
  59
  60 /************************************************************************
  61  * Macros and definitions
  62  ************************************************************************/
  63
  64 #define MAX_LINE_LENGTH 256
  65
  66 /* SAP is always on that port */
  67 #define SAP_PORT 9875
  68 /* Global-scope SAP address */
  69 #define SAP_V4_GLOBAL_ADDRESS   "224.2.127.254"
  70 /* Organization-local SAP address */
  71 #define SAP_V4_ORG_ADDRESS      "239.195.255.255"
  72 /* Local (smallest non-link-local scope) SAP address */
  73 #define SAP_V4_LOCAL_ADDRESS    "239.255.255.255"
  74 /* Link-local SAP address */
  75 #define SAP_V4_LINK_ADDRESS     "224.0.0.255"
  76 #define ADD_SESSION 1
  77
  78 /*****************************************************************************
  79  * Module descriptor
  80  *****************************************************************************/
  81 #define SAP_ADDR_TEXT N_( "SAP multicast address" )
  82 #define SAP_ADDR_LONGTEXT N_( "The SAP module normally chooses itself the " \
  83                               "right addresses to listen to. However, you " \
  84                               "can specify a specific address." )
  85 #define SAP_TIMEOUT_TEXT N_( "SAP timeout (seconds)" )
  86 #define SAP_TIMEOUT_LONGTEXT N_( \
  87        "Delay after which SAP items get deleted if no new announcement " \
  88        "is received." )
  89 #define SAP_PARSE_TEXT N_( "Try to parse the announce" )
  90 #define SAP_PARSE_LONGTEXT N_( \
  91        "This enables actual parsing of the announces by the SAP module. " \
  92        "Otherwise, all announcements are parsed by the \"live555\" " \
  93        "(RTP/RTSP) module." )
  94 #define SAP_STRICT_TEXT N_( "SAP Strict mode" )
  95 #define SAP_STRICT_LONGTEXT N_( \
  96        "When this is set, the SAP parser will discard some non-compliant " \
  97        "announcements." )
  98
  99 /* Callbacks */
 100     static int  Open ( vlc_object_t * );
 101     static void Close( vlc_object_t * );
 102     static int  OpenDemux ( vlc_object_t * );
 103     static void CloseDemux ( vlc_object_t * );
 104
 105 VLC_SD_PROBE_HELPER("sap", "Network streams (SAP)", SD_CAT_LAN)
 106
 107 vlc_module_begin ()
 108     set_shortname( N_("SAP"))
 109     set_description( N_("Network streams (SAP)") )
 110     set_category( CAT_PLAYLIST )
 111     set_subcategory( SUBCAT_PLAYLIST_SD )
 112
 113     add_string( "sap-addr", NULL,
 114                 SAP_ADDR_TEXT, SAP_ADDR_LONGTEXT, true )
 115     add_obsolete_bool( "sap-ipv4" ) /* since 2.0.0 */
 116     add_obsolete_bool( "sap-ipv6" ) /* since 2.0.0 */
 117     add_integer( "sap-timeout", 1800,
 118                  SAP_TIMEOUT_TEXT, SAP_TIMEOUT_LONGTEXT, true )
 119     add_bool( "sap-parse", true,
 120                SAP_PARSE_TEXT,SAP_PARSE_LONGTEXT, true )
 121     add_bool( "sap-strict", false,
 122                SAP_STRICT_TEXT,SAP_STRICT_LONGTEXT, true )
 123     add_obsolete_bool( "sap-timeshift" ) /* Redumdant since 1.0.0 */
 124
 125     set_capability( "services_discovery", 0 )
 126     set_callbacks( Open, Close )
 127
 128     VLC_SD_PROBE_SUBMODULE
 129
 130     add_submodule ()
 131         set_description( N_("SDP Descriptions parser") )
 132         add_shortcut( "sdp" )
 133         set_capability( "demux", 51 )
 134         set_callbacks( OpenDemux, CloseDemux )
 135 vlc_module_end ()
 136
 137
 138 /*****************************************************************************
 139  * Local structures
 140  *****************************************************************************/
 141
 142 typedef struct sdp_t sdp_t;
 143 typedef struct attribute_t attribute_t;
 144 typedef struct sap_announce_t sap_announce_t;
 145
 146
 147 struct sdp_media_t
 148 {
 149     struct sdp_t           *parent;
 150     char                   *fmt;
 151     struct sockaddr_storage addr;
 152     socklen_t               addrlen;
 153     unsigned                n_addr;
 154     int           i_attributes;
 155     attribute_t  **pp_attributes;
 156 };
 157
 158
 159 /* The structure that contains sdp information */
 160 struct  sdp_t
 161 {
 162     const char *psz_sdp;
 163
 164     /* o field */
 165     char     username[64];
 166     uint64_t session_id;
 167     uint64_t session_version;
 168     unsigned orig_ip_version;
 169     char     orig_host[1024];
 170
 171     /* s= field */
 172     char *psz_sessionname;
 173
 174     /* i= field */
 175     char *psz_sessioninfo;
 176
 177     /* old cruft */
 178     /* "computed" URI */
 179     char *psz_uri;
 180     int           i_media_type;
 181     unsigned rtcp_port;
 182
 183     /* a= global attributes */
 184     int           i_attributes;
 185     attribute_t  **pp_attributes;
 186
 187     /* medias (well, we only support one atm) */
 188     unsigned            mediac;
 189     struct sdp_media_t *mediav;
 190 };
 191
 192 struct attribute_t
 193 {
 194     const char *value;
 195     char name[];
 196 };
 197
 198 struct sap_announce_t
 199 {
 200     mtime_t i_last;
 201     mtime_t i_period;
 202     uint8_t i_period_trust;
 203
 204     uint16_t    i_hash;
 205     uint32_t    i_source[4];
 206
 207     /* SAP annnounces must only contain one SDP */
 208     sdp_t       *p_sdp;
 209
 210     input_item_t * p_item;
 211 };
 212
 213 struct services_discovery_sys_t
 214 {
 215     vlc_thread_t thread;
 216
 217     /* Socket descriptors */
 218     int i_fd;
 219     int *pi_fd;
 220
 221     /* Table of announces */
 222     int i_announces;
 223     struct sap_announce_t **pp_announces;
 224
 225     /* Modes */
 226     bool  b_strict;
 227     bool  b_parse;
 228
 229     int i_timeout;
 230 };
 231
 232 struct demux_sys_t
 233 {
 234     sdp_t *p_sdp;
 235 };
 236
 237 /*****************************************************************************
 238  * Local prototypes
 239  *****************************************************************************/
 240
 241
 242 /* Main functions */
 243     static int Demux( demux_t *p_demux );
 244     static int Control( demux_t *, int, va_list );
 245     static void *Run  ( void *p_sd );
 246
 247 /* Main parsing functions */
 248     static int ParseConnection( vlc_object_t *p_obj, sdp_t *p_sdp );
 249     static int ParseSAP( services_discovery_t *p_sd, const uint8_t *p_buffer, size_t i_read );
 250     static sdp_t *ParseSDP (vlc_object_t *p_sd, const char *psz_sdp);
 251     static sap_announce_t *CreateAnnounce( services_discovery_t *, uint32_t *, uint16_t, sdp_t * );
 252     static int RemoveAnnounce( services_discovery_t *p_sd, sap_announce_t *p_announce );
 253
 254 /* Helper functions */
 255     static inline attribute_t *MakeAttribute (const char *str);
 256     static const char *GetAttribute (attribute_t **tab, unsigned n, const char *name);
 257     static inline void FreeAttribute (attribute_t *a);
 258     static const char *FindAttribute (const sdp_t *sdp, unsigned media,
 259                                       const char *name);
 260
 261     static bool IsSameSession( sdp_t *p_sdp1, sdp_t *p_sdp2 );
 262     static int InitSocket( services_discovery_t *p_sd, const char *psz_address, int i_port );
 263     static int Decompress( const unsigned char *psz_src, unsigned char **_dst, int i_len );
 264     static void FreeSDP( sdp_t *p_sdp );
 265
 266 static inline int min_int( int a, int b )
 267 {
 268     return a > b ? b : a;
 269 }
 270
 271 static bool IsWellKnownPayload (int type)
 272 {
 273     switch (type)
 274     {   /* Should be in sync with modules/demux/rtp.c */
 275         case  0: /* PCMU/8000 */
 276         case  3:
 277         case  8: /* PCMA/8000 */
 278         case 10: /* L16/44100/2 */
 279         case 11: /* L16/44100 */
 280         case 12:
 281         case 14: /* MPA/90000 */
 282         case 32: /* MPV/90000 */
 283         case 33: /* MP2/90000 */
 284             return true;
 285    }
 286    return false;
 287 }
 288
 289 /*****************************************************************************
 290  * Open: initialize and create stuff
 291  *****************************************************************************/
 292 static int Open( vlc_object_t *p_this )
 293 {
 294     services_discovery_t *p_sd = ( services_discovery_t* )p_this;
 295     services_discovery_sys_t *p_sys  = (services_discovery_sys_t *)
 296                                 malloc( sizeof( services_discovery_sys_t ) );
 297     if( !p_sys )
 298         return VLC_ENOMEM;
 299
 300     p_sys->i_timeout = var_CreateGetInteger( p_sd, "sap-timeout" );
 301
 302     p_sd->p_sys  = p_sys;
 303
 304     p_sys->pi_fd = NULL;
 305     p_sys->i_fd = 0;
 306
 307     p_sys->b_strict = var_CreateGetBool( p_sd, "sap-strict");
 308     p_sys->b_parse = var_CreateGetBool( p_sd, "sap-parse" );
 309
 310     p_sys->i_announces = 0;
 311     p_sys->pp_announces = NULL;
 312     /* TODO: create sockets here, and fix racy sockets table */
 313     if (vlc_clone (&p_sys->thread, Run, p_sd, VLC_THREAD_PRIORITY_LOW))
 314     {
 315         free (p_sys);
 316         return VLC_EGENERIC;
 317     }
 318
 319     return VLC_SUCCESS;
 320 }
 321
 322 /*****************************************************************************
 323  * OpenDemux: initialize and create stuff
 324  *****************************************************************************/
 325 static int OpenDemux( vlc_object_t *p_this )
 326 {
 327     demux_t *p_demux = (demux_t *)p_this;
 328     const uint8_t *p_peek;
 329     char *psz_sdp = NULL;
 330     sdp_t *p_sdp = NULL;
 331     int errval = VLC_EGENERIC;
 332     size_t i_len;
 333
 334     if( !var_CreateGetBool( p_demux, "sap-parse" ) )
 335     {
 336         /* We want livedotcom module to parse this SDP file */
 337         return VLC_EGENERIC;
 338     }
 339
 340     assert( p_demux->s ); /* this is NOT an access_demux */
 341
 342     /* Probe for SDP */
 343     if( stream_Peek( p_demux->s, &p_peek, 7 ) < 7 )
 344         return VLC_EGENERIC;
 345
 346     if( memcmp( p_peek, "v=0\r\no=", 7 ) && memcmp( p_peek, "v=0\no=", 6 ) )
 347         return VLC_EGENERIC;
 348
 349     /* Gather the complete sdp file */
 350     for( i_len = 0, psz_sdp = NULL; i_len < 65536; )
 351     {
 352         const int i_read_max = 1024;
 353         char *psz_sdp_new = realloc( psz_sdp, i_len + i_read_max + 1 );
 354         size_t i_read;
 355         if( psz_sdp_new == NULL )
 356         {
 357             errval = VLC_ENOMEM;
 358             goto error;
 359         }
 360         psz_sdp = psz_sdp_new;
 361
 362         i_read = stream_Read( p_demux->s, &psz_sdp[i_len], i_read_max );
 363         if( (int)i_read < 0 )
 364         {
 365             msg_Err( p_demux, "cannot read SDP" );
 366             goto error;
 367         }
 368         i_len += i_read;
 369
 370         psz_sdp[i_len] = '\0';
 371
 372         if( (int)i_read < i_read_max )
 373             break; // EOF
 374     }
 375
 376     p_sdp = ParseSDP( VLC_OBJECT(p_demux), psz_sdp );
 377
 378     if( !p_sdp )
 379     {
 380         msg_Warn( p_demux, "invalid SDP");
 381         goto error;
 382     }
 383
 384     if( ParseConnection( VLC_OBJECT( p_demux ), p_sdp ) )
 385     {
 386         p_sdp->psz_uri = NULL;
 387     }
 388     if (!IsWellKnownPayload (p_sdp->i_media_type))
 389         goto error;
 390     if( p_sdp->psz_uri == NULL ) goto error;
 391
 392     p_demux->p_sys = (demux_sys_t *)malloc( sizeof(demux_sys_t) );
 393     if( unlikely( !p_demux->p_sys ) )
 394         goto error;
 395     p_demux->p_sys->p_sdp = p_sdp;
 396     p_demux->pf_control = Control;
 397     p_demux->pf_demux = Demux;
 398
 399     FREENULL( psz_sdp );
 400     return VLC_SUCCESS;
 401
 402 error:
 403     FREENULL( psz_sdp );
 404     if( p_sdp ) FreeSDP( p_sdp ); p_sdp = NULL;
 405     stream_Seek( p_demux->s, 0 );
 406     return errval;
 407 }
 408
 409 /*****************************************************************************
 410  * Close:
 411  *****************************************************************************/
 412 static void Close( vlc_object_t *p_this )
 413 {
 414     services_discovery_t *p_sd = ( services_discovery_t* )p_this;
 415     services_discovery_sys_t    *p_sys  = p_sd->p_sys;
 416     int i;
 417
 418     vlc_cancel (p_sys->thread);
 419     vlc_join (p_sys->thread, NULL);
 420
 421     for( i = p_sys->i_fd-1 ; i >= 0 ; i-- )
 422     {
 423         net_Close( p_sys->pi_fd[i] );
 424     }
 425     FREENULL( p_sys->pi_fd );
 426
 427     for( i = p_sys->i_announces  - 1;  i>= 0; i-- )
 428     {
 429         RemoveAnnounce( p_sd, p_sys->pp_announces[i] );
 430     }
 431     FREENULL( p_sys->pp_announces );
 432
 433     free( p_sys );
 434 }
 435
 436 /*****************************************************************************
 437  * CloseDemux: Close the demuxer
 438  *****************************************************************************/
 439 static void CloseDemux( vlc_object_t *p_this )
 440 {
 441     demux_t *p_demux = (demux_t *)p_this;
 442
 443     if( p_demux->p_sys->p_sdp )
 444         FreeSDP( p_demux->p_sys->p_sdp );
 445     free( p_demux->p_sys );
 446 }
 447
 448 /*****************************************************************************
 449  * Run: main SAP thread
 450  *****************************************************************************
 451  * Listens to SAP packets, and sends them to packet_handle
 452  *****************************************************************************/
 453 #define MAX_SAP_BUFFER 5000
 454
 455 static void *Run( void *data )
 456 {
 457     services_discovery_t *p_sd = data;
 458     char *psz_addr;
 459     int i;
 460     int timeout = -1;
 461     int canc = vlc_savecancel ();
 462
 463     /* Braindead Winsock DNS resolver will get stuck over 2 seconds per failed
 464      * DNS queries, even if the DNS server returns an error with milliseconds.
 465      * You don't want to know why the bug (as of XP SP2) wasn't fixed since
 466      * Winsock 1.1 from Windows 95, if not Windows 3.1.
 467      * Anyway, to avoid a 30 seconds delay for failed IPv6 socket creation,
 468      * we have to open sockets in Run() rather than Open(). */
 469     InitSocket( p_sd, SAP_V4_GLOBAL_ADDRESS, SAP_PORT );
 470     InitSocket( p_sd, SAP_V4_ORG_ADDRESS, SAP_PORT );
 471     InitSocket( p_sd, SAP_V4_LOCAL_ADDRESS, SAP_PORT );
 472     InitSocket( p_sd, SAP_V4_LINK_ADDRESS, SAP_PORT );
 473
 474     char psz_address[NI_MAXNUMERICHOST] = "ff02::2:7ffe%";
 475 #ifndef _WIN32
 476     struct if_nameindex *l = if_nameindex ();
 477     if (l != NULL)
 478     {
 479         char *ptr = strchr (psz_address, '%') + 1;
 480         for (unsigned i = 0; l[i].if_index; i++)
 481         {
 482             strcpy (ptr, l[i].if_name);
 483             InitSocket (p_sd, psz_address, SAP_PORT);
 484         }
 485         if_freenameindex (l);
 486     }
 487 #else
 488         /* this is the Winsock2 equivalant of SIOCGIFCONF on BSD stacks,
 489            which if_nameindex uses internally anyway */
 490
 491         // first create a dummy socket to pin down the protocol family
 492         SOCKET s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_UDP);
 493         if( s != INVALID_SOCKET )
 494         {
 495             INTERFACE_INFO ifaces[10]; // Assume there will be no more than 10 IP interfaces
 496             DWORD len = sizeof(ifaces);
 497
 498             if( SOCKET_ERROR != WSAIoctl(s, SIO_GET_INTERFACE_LIST, NULL, 0, &ifaces, len, &len, NULL, NULL) )
 499             {
 500                 unsigned ifcount = len/sizeof(INTERFACE_INFO);
 501                 char *ptr = strchr (psz_address, '%') + 1;
 502                 for(unsigned i = 1; i<=ifcount; ++i )
 503                 {
 504                     // append link-local zone identifier
 505                     sprintf(ptr, "%d", i);
 506                 }
 507             }
 508             closesocket(s);
 509         }
 510 #endif
 511     *strchr (psz_address, '%') = '\0';
 512
 513     static const char ipv6_scopes[] = "1456789ABCDE";
 514     for (const char *c_scope = ipv6_scopes; *c_scope; c_scope++)
 515     {
 516         psz_address[3] = *c_scope;
 517         InitSocket( p_sd, psz_address, SAP_PORT );
 518     }
 519
 520     psz_addr = var_CreateGetString( p_sd, "sap-addr" );
 521     if( psz_addr && *psz_addr )
 522         InitSocket( p_sd, psz_addr, SAP_PORT );
 523     free( psz_addr );
 524
 525     if( p_sd->p_sys->i_fd == 0 )
 526     {
 527         msg_Err( p_sd, "unable to listen on any address" );
 528         return NULL;
 529     }
 530
 531     /* read SAP packets */
 532     for (;;)
 533     {
 534         vlc_restorecancel (canc);
 535         unsigned n = p_sd->p_sys->i_fd;
 536         struct pollfd ufd[n];
 537
 538         for (unsigned i = 0; i < n; i++)
 539         {
 540             ufd[i].fd = p_sd->p_sys->pi_fd[i];
 541             ufd[i].events = POLLIN;
 542             ufd[i].revents = 0;
 543         }
 544
 545         int val = poll (ufd, n, timeout);
 546         canc = vlc_savecancel ();
 547         if (val > 0)
 548         {
 549             for (unsigned i = 0; i < n; i++)
 550             {
 551                 if (ufd[i].revents)
 552                 {
 553                     uint8_t p_buffer[MAX_SAP_BUFFER+1];
 554                     ssize_t i_read;
 555
 556                     i_read = net_Read (p_sd, ufd[i].fd, NULL, p_buffer,
 557                                        MAX_SAP_BUFFER, false);
 558                     if (i_read < 0)
 559                         msg_Warn (p_sd, "receive error: %s",
 560                                   vlc_strerror_c(errno));
 561                     if (i_read > 6)
 562                     {
 563                         /* Parse the packet */
 564                         p_buffer[i_read] = '\0';
 565                         ParseSAP (p_sd, p_buffer, i_read);
 566                     }
 567                 }
 568             }
 569         }
 570
 571         mtime_t now = mdate();
 572
 573         /* A 1 hour timeout correspond to the RFC Implicit timeout.
 574          * This timeout is tuned in the following loop. */
 575         timeout = 1000 * 60 * 60;
 576
 577         /* Check for items that need deletion */
 578         for( i = 0; i < p_sd->p_sys->i_announces; i++ )
 579         {
 580             mtime_t i_timeout = ( mtime_t ) 1000000 * p_sd->p_sys->i_timeout;
 581             sap_announce_t * p_announce = p_sd->p_sys->pp_announces[i];
 582             mtime_t i_last_period = now - p_announce->i_last;
 583
 584             /* Remove the announcement, if the last announcement was 1 hour ago
 585              * or if the last packet emitted was 3 times the average time
 586              * between two packets */
 587             if( ( p_announce->i_period_trust > 5 && i_last_period > 3 * p_announce->i_period ) ||
 588                 i_last_period > i_timeout )
 589             {
 590                 RemoveAnnounce( p_sd, p_announce );
 591             }
 592             else
 593             {
 594                 /* Compute next timeout */
 595                 if( p_announce->i_period_trust > 5 )
 596                     timeout = min_int((3 * p_announce->i_period - i_last_period) / 1000, timeout);
 597                 timeout = min_int((i_timeout - i_last_period)/1000, timeout);
 598             }
 599         }
 600
 601         if( !p_sd->p_sys->i_announces )
 602             timeout = -1; /* We can safely poll indefinitely. */
 603         else if( timeout < 200 )
 604             timeout = 200; /* Don't wakeup too fast. */
 605     }
 606     assert (0);
 607 }
 608
 609 /**********************************************************************
 610  * Demux: reads and demuxes data packets
 611  * Return -1 if error, 0 if EOF, 1 else
 612  **********************************************************************/
 613 static int Demux( demux_t *p_demux )
 614 {
 615     sdp_t *p_sdp = p_demux->p_sys->p_sdp;
 616     input_thread_t *p_input;
 617     input_item_t *p_parent_input;
 618
 619     p_input = demux_GetParentInput( p_demux );
 620     assert( p_input );
 621     if( !p_input )
 622     {
 623         msg_Err( p_demux, "parent input could not be found" );
 624         return VLC_EGENERIC;
 625     }
 626
 627     /* This item hasn't been held by input_GetItem
 628      * don't release it */
 629     p_parent_input = input_GetItem( p_input );
 630
 631     input_item_SetURI( p_parent_input, p_sdp->psz_uri );
 632     input_item_SetName( p_parent_input, p_sdp->psz_sessionname );
 633     if( p_sdp->rtcp_port )
 634     {
 635         char *rtcp;
 636         if( asprintf( &rtcp, ":rtcp-port=%u", p_sdp->rtcp_port ) != -1 )
 637         {
 638             input_item_AddOption( p_parent_input, rtcp, VLC_INPUT_OPTION_TRUSTED );
 639             free( rtcp );
 640         }
 641     }
 642
 643     vlc_mutex_lock( &p_parent_input->lock );
 644
 645     p_parent_input->i_type = ITEM_TYPE_NET;
 646
 647     vlc_mutex_unlock( &p_parent_input->lock );
 648     vlc_object_release( p_input );
 649     return VLC_SUCCESS;
 650 }
 651
 652 static int Control( demux_t *p_demux, int i_query, va_list args )
 653 {
 654     VLC_UNUSED(p_demux); VLC_UNUSED(i_query); VLC_UNUSED(args);
 655     return VLC_EGENERIC;
 656 }
 657
 658 /**************************************************************
 659  * Local functions
 660  **************************************************************/
 661
 662 /* i_read is at least > 6 */
 663 static int ParseSAP( services_discovery_t *p_sd, const uint8_t *buf,
 664                      size_t len )
 665 {
 666     int i;
 667     const char          *psz_sdp;
 668     const uint8_t *end = buf + len;
 669     sdp_t               *p_sdp;
 670     uint32_t            i_source[4];
 671
 672     assert (buf[len] == '\0');
 673
 674     if (len < 4)
 675         return VLC_EGENERIC;
 676
 677     uint8_t flags = buf[0];
 678     uint8_t auth_len = buf[1];
 679
 680     /* First, check the sap announce is correct */
 681     if ((flags >> 5) != 1)
 682         return VLC_EGENERIC;
 683
 684     bool b_ipv6 = (flags & 0x10) != 0;
 685     bool b_need_delete = (flags & 0x04) != 0;
 686
 687     if (flags & 0x02)
 688     {
 689         msg_Dbg( p_sd, "encrypted packet, unsupported" );
 690         return VLC_EGENERIC;
 691     }
 692
 693     bool b_compressed = (flags & 0x01) != 0;
 694
 695     uint16_t i_hash = U16_AT (buf + 2);
 696
 697     if( p_sd->p_sys->b_strict && i_hash == 0 )
 698     {
 699         msg_Dbg( p_sd, "strict mode, discarding announce with null id hash");
 700         return VLC_EGENERIC;
 701     }
 702
 703     buf += 4;
 704     if( b_ipv6 )
 705     {
 706         for( int i = 0; i < 4; i++,buf+=4)
 707             i_source[i] = U32_AT(buf);
 708     }
 709     else
 710     {
 711         memset(i_source, 0, sizeof(i_source));
 712         i_source[3] = U32_AT(buf);
 713         buf+=4;
 714     }
 715     // Skips auth data
 716     buf += auth_len;
 717     if (buf > end)
 718         return VLC_EGENERIC;
 719
 720     uint8_t *decomp = NULL;
 721     if( b_compressed )
 722     {
 723         int newsize = Decompress (buf, &decomp, end - buf);
 724         if (newsize < 0)
 725         {
 726             msg_Dbg( p_sd, "decompression of SAP packet failed" );
 727             return VLC_EGENERIC;
 728         }
 729
 730         decomp = realloc (decomp, newsize + 1);
 731         decomp[newsize] = '\0';
 732         psz_sdp = (const char *)decomp;
 733         len = newsize;
 734     }
 735     else
 736     {
 737         psz_sdp = (const char *)buf;
 738         len = end - buf;
 739     }
 740
 741     /* len is a strlen here here. both buf and decomp are len+1 where the 1 should be a \0 */
 742     assert( psz_sdp[len] == '\0');
 743
 744     /* Skip payload type */
 745     /* SAPv1 has implicit "application/sdp" payload type: first line is v=0 */
 746     if (strncmp (psz_sdp, "v=0", 3))
 747     {
 748         size_t clen = strlen (psz_sdp) + 1;
 749
 750         if (strcmp (psz_sdp, "application/sdp"))
 751         {
 752             msg_Dbg (p_sd, "unsupported content type: %s", psz_sdp);
 753             goto error;
 754         }
 755
 756         // skips content type
 757         if (len <= clen)
 758             goto error;
 759
 760         len -= clen;
 761         psz_sdp += clen;
 762     }
 763
 764     /* Parse SDP info */
 765     p_sdp = ParseSDP( VLC_OBJECT(p_sd), psz_sdp );
 766
 767     if( p_sdp == NULL )
 768         goto error;
 769
 770     p_sdp->psz_sdp = psz_sdp;
 771
 772     /* Decide whether we should add a playlist item for this SDP */
 773     /* Parse connection information (c= & m= ) */
 774     if( ParseConnection( VLC_OBJECT(p_sd), p_sdp ) )
 775         p_sdp->psz_uri = NULL;
 776
 777     /* Multi-media or no-parse -> pass to LIVE.COM */
 778     if( !IsWellKnownPayload( p_sdp->i_media_type ) || !p_sd->p_sys->b_parse )
 779     {
 780         free( p_sdp->psz_uri );
 781         if (asprintf( &p_sdp->psz_uri, "sdp://%s", p_sdp->psz_sdp ) == -1)
 782             p_sdp->psz_uri = NULL;
 783     }
 784
 785     if( p_sdp->psz_uri == NULL )
 786     {
 787         FreeSDP( p_sdp );
 788         goto error;
 789     }
 790
 791     for( i = 0 ; i< p_sd->p_sys->i_announces ; i++ )
 792     {
 793         sap_announce_t * p_announce = p_sd->p_sys->pp_announces[i];
 794         /* FIXME: slow */
 795         if( ( !i_hash && IsSameSession( p_announce->p_sdp, p_sdp ) )
 796             || ( i_hash && p_announce->i_hash == i_hash
 797                  && !memcmp(p_announce->i_source, i_source, sizeof(i_source)) ) )
 798         {
 799             /* We don't support delete announcement as they can easily
 800              * Be used to highjack an announcement by a third party.
 801              * Instead we cleverly implement Implicit Announcement removal.
 802              *
 803              * if( b_need_delete )
 804              *    RemoveAnnounce( p_sd, p_sd->p_sys->pp_announces[i]);
 805              * else
 806              */
 807
 808             if( !b_need_delete )
 809             {
 810                 /* No need to go after six, as we start to trust the
 811                  * average period at six */
 812                 if( p_announce->i_period_trust <= 5 )
 813                     p_announce->i_period_trust++;
 814
 815                 /* Compute the average period */
 816                 mtime_t now = mdate();
 817                 p_announce->i_period = ( p_announce->i_period * (p_announce->i_period_trust-1) + (now - p_announce->i_last) ) / p_announce->i_period_trust;
 818                 p_announce->i_last = now;
 819             }
 820             FreeSDP( p_sdp );
 821             free (decomp);
 822             return VLC_SUCCESS;
 823         }
 824     }
 825
 826     CreateAnnounce( p_sd, i_source, i_hash, p_sdp );
 827
 828     free (decomp);
 829     return VLC_SUCCESS;
 830 error:
 831     free (decomp);
 832     return VLC_EGENERIC;
 833 }
 834
 835 sap_announce_t *CreateAnnounce( services_discovery_t *p_sd, uint32_t *i_source, uint16_t i_hash,
 836                                 sdp_t *p_sdp )
 837 {
 838     input_item_t *p_input;
 839     const char *psz_value;
 840     sap_announce_t *p_sap = (sap_announce_t *)malloc(
 841                                         sizeof(sap_announce_t ) );
 842     services_discovery_sys_t *p_sys;
 843     if( p_sap == NULL )
 844         return NULL;
 845
 846     p_sys = p_sd->p_sys;
 847
 848     p_sap->i_last = mdate();
 849     p_sap->i_period = 0;
 850     p_sap->i_period_trust = 0;
 851     p_sap->i_hash = i_hash;
 852     memcpy (p_sap->i_source, i_source, sizeof(p_sap->i_source));
 853     p_sap->p_sdp = p_sdp;
 854
 855     /* Released in RemoveAnnounce */
 856     p_input = input_item_NewWithType( p_sap->p_sdp->psz_uri,
 857                                       p_sdp->psz_sessionname,
 858                                       0, NULL, 0, -1, ITEM_TYPE_NET );
 859     if( unlikely(p_input == NULL) )
 860     {
 861         free( p_sap );
 862         return NULL;
 863     }
 864     p_sap->p_item = p_input;
 865
 866     vlc_meta_t *p_meta = vlc_meta_New();
 867     if( likely(p_meta != NULL) )
 868     {
 869         vlc_meta_Set( p_meta, vlc_meta_Description, p_sdp->psz_sessioninfo );
 870         p_input->p_meta = p_meta;
 871     }
 872
 873     if( p_sdp->rtcp_port )
 874     {
 875         char *rtcp;
 876         if( asprintf( &rtcp, ":rtcp-port=%u", p_sdp->rtcp_port ) != -1 )
 877         {
 878             input_item_AddOption( p_input, rtcp, VLC_INPUT_OPTION_TRUSTED );
 879             free( rtcp );
 880         }
 881     }
 882
 883     psz_value = GetAttribute( p_sap->p_sdp->pp_attributes, p_sap->p_sdp->i_attributes, "tool" );
 884     if( psz_value != NULL )
 885     {
 886         input_item_AddInfo( p_input, _("Session"), _("Tool"), "%s", psz_value );
 887     }
 888     if( strcmp( p_sdp->username, "-" ) )
 889     {
 890         input_item_AddInfo( p_input, _("Session"), _("User"), "%s",
 891                            p_sdp->username );
 892     }
 893
 894     /* Handle category */
 895     psz_value = GetAttribute(p_sap->p_sdp->pp_attributes,
 896                              p_sap->p_sdp->i_attributes, "cat");
 897     if (psz_value != NULL)
 898     {
 899         /* a=cat provides a dot-separated hierarchy.
 900          * For the time being only replace dots with pipe. TODO: FIXME */
 901         char *str = strdup(psz_value);
 902         if (likely(str != NULL))
 903             for (char *p = strchr(str, '.'); p != NULL; p = strchr(p, '.'))
 904                 *(p++) = '|';
 905         services_discovery_AddItem(p_sd, p_input, str ? str : psz_value);
 906         free(str);
 907     }
 908     else
 909     {
 910         /* backward compatibility with VLC 0.7.3-2.0.0 senders */
 911         psz_value = GetAttribute(p_sap->p_sdp->pp_attributes,
 912                                  p_sap->p_sdp->i_attributes, "x-plgroup");
 913         services_discovery_AddItem(p_sd, p_input, psz_value);
 914     }
 915
 916     TAB_APPEND( p_sys->i_announces, p_sys->pp_announces, p_sap );
 917
 918     return p_sap;
 919 }
 920
 921
 922 static const char *FindAttribute (const sdp_t *sdp, unsigned media,
 923                                   const char *name)
 924 {
 925     /* Look for media attribute, and fallback to session */
 926     const char *attr = GetAttribute (sdp->mediav[media].pp_attributes,
 927                                      sdp->mediav[media].i_attributes, name);
 928     if (attr == NULL)
 929         attr = GetAttribute (sdp->pp_attributes, sdp->i_attributes, name);
 930     return attr;
 931 }
 932
 933
 934 /* Fill p_sdp->psz_uri */
 935 static int ParseConnection( vlc_object_t *p_obj, sdp_t *p_sdp )
 936 {
 937     if (p_sdp->mediac == 0)
 938     {
 939         msg_Dbg (p_obj, "Ignoring SDP with no media");
 940         return VLC_EGENERIC;
 941     }
 942
 943     for (unsigned i = 1; i < p_sdp->mediac; i++)
 944     {
 945         if ((p_sdp->mediav[i].n_addr != p_sdp->mediav->n_addr)
 946          || (p_sdp->mediav[i].addrlen != p_sdp->mediav->addrlen)
 947          || memcmp (&p_sdp->mediav[i].addr, &p_sdp->mediav->addr,
 948                     p_sdp->mediav->addrlen))
 949         {
 950             msg_Dbg (p_obj, "Multiple media ports not supported -> live555");
 951             return VLC_EGENERIC;
 952         }
 953     }
 954
 955     if (p_sdp->mediav->n_addr != 1)
 956     {
 957         msg_Dbg (p_obj, "Layered encoding not supported -> live555");
 958         return VLC_EGENERIC;
 959     }
 960
 961     char psz_uri[1026];
 962     const char *host;
 963     int port;
 964
 965     psz_uri[0] = '[';
 966     if (vlc_getnameinfo ((struct sockaddr *)&(p_sdp->mediav->addr),
 967                          p_sdp->mediav->addrlen, psz_uri + 1,
 968                          sizeof (psz_uri) - 2, &port, NI_NUMERICHOST))
 969         return VLC_EGENERIC;
 970
 971     if (strchr (psz_uri + 1, ':'))
 972     {
 973         host = psz_uri;
 974         strcat (psz_uri, "]");
 975     }
 976     else
 977         host = psz_uri + 1;
 978
 979     /* Parse m= field */
 980     char *sdp_proto = strdup (p_sdp->mediav[0].fmt);
 981     if (sdp_proto == NULL)
 982         return VLC_ENOMEM;
 983
 984     char *subtype = strchr (sdp_proto, ' ');
 985     if (subtype == NULL)
 986     {
 987         msg_Dbg (p_obj, "missing SDP media subtype: %s", sdp_proto);
 988         free (sdp_proto);
 989         return VLC_EGENERIC;
 990     }
 991     else
 992     {
 993         *subtype++ = '\0';
 994         /* FIXME: check for multiple payload types in RTP/AVP case.
 995          * FIXME: check for "mpeg" subtype in raw udp case. */
 996         if (!strcasecmp (sdp_proto, "udp"))
 997             p_sdp->i_media_type = 33;
 998         else
 999             p_sdp->i_media_type = atoi (subtype);
1000     }
1001
1002     /* RTP protocol, nul, VLC shortcut, nul, flags byte as follow:
1003      * 0x1: Connection-Oriented media. */
1004     static const char proto_match[] =
1005         "udp\0"             "udp\0\0"
1006         "RTP/AVP\0"         "rtp\0\0"
1007         "UDPLite/RTP/AVP\0" "udplite\0\0"
1008         "DCCP/RTP/AVP\0"    "dccp\0\1"
1009         "TCP/RTP/AVP\0"     "rtptcp\0\1"
1010         "\0";
1011
1012     const char *vlc_proto = NULL;
1013     uint8_t flags = 0;
1014     for (const char *proto = proto_match; *proto;)
1015     {
1016         if (strcasecmp (proto, sdp_proto) == 0)
1017         {
1018             vlc_proto = proto + strlen (proto) + 1;
1019             flags = vlc_proto[strlen (vlc_proto) + 1];
1020             break;
1021         }
1022         proto += strlen (proto) + 1;
1023         proto += strlen (proto) + 2;
1024     }
1025
1026     free (sdp_proto);
1027     if (vlc_proto == NULL)
1028     {
1029         msg_Dbg (p_obj, "unknown SDP media protocol: %s",
1030                  p_sdp->mediav[0].fmt);
1031         return VLC_EGENERIC;
1032     }
1033
1034     if (!strcmp (vlc_proto, "udp") || FindAttribute (p_sdp, 0, "rtcp-mux"))
1035         p_sdp->rtcp_port = 0;
1036     else
1037     {
1038         const char *rtcp = FindAttribute (p_sdp, 0, "rtcp");
1039         if (rtcp)
1040             p_sdp->rtcp_port = atoi (rtcp);
1041         else
1042         if (port & 1) /* odd port -> RTCP; next even port -> RTP */
1043             p_sdp->rtcp_port = port++;
1044         else /* even port -> RTP; next odd port -> RTCP */
1045             p_sdp->rtcp_port = port + 1;
1046     }
1047
1048     if (flags & 1)
1049     {
1050         /* Connection-oriented media */
1051         const char *setup = FindAttribute (p_sdp, 0, "setup");
1052         if (setup == NULL)
1053             setup = "active"; /* default value */
1054
1055         if (strcmp (setup, "actpass") && strcmp (setup, "passive"))
1056         {
1057             msg_Dbg (p_obj, "unsupported COMEDIA mode: %s", setup);
1058             return VLC_EGENERIC;
1059         }
1060
1061         if (asprintf (&p_sdp->psz_uri, "%s://%s:%d", vlc_proto,
1062                       host, port) == -1)
1063             return VLC_ENOMEM;
1064     }
1065     else
1066     {
1067         /* Non-connected (normally multicast) media */
1068         char psz_source[258] = "";
1069         const char *sfilter = FindAttribute (p_sdp, 0, "source-filter");
1070         if (sfilter != NULL)
1071         {
1072             char psz_source_ip[256];
1073             unsigned ipv;
1074
1075             if (sscanf (sfilter, " incl IN IP%u %*s %255s ", &ipv,
1076                         psz_source_ip) == 2)
1077             {
1078                 /* According to RFC4570, FQDNs can be used for source-filters,
1079                  * but -seriously- this is impractical */
1080                 switch (ipv)
1081                 {
1082 #ifdef AF_INET6
1083                     case 6:
1084                     {
1085                         struct in6_addr addr;
1086                         if ((inet_pton (AF_INET6, psz_source_ip, &addr) > 0)
1087                         && (inet_ntop (AF_INET6, &addr, psz_source + 1,
1088                                         sizeof (psz_source) - 2) != NULL))
1089                         {
1090                             psz_source[0] = '[';
1091                             psz_source[strlen (psz_source)] = ']';
1092                         }
1093                         break;
1094                     }
1095 #endif
1096                     case 4:
1097                     {
1098                         struct in_addr addr;
1099                         if ((inet_pton (AF_INET, psz_source_ip, &addr) > 0)
1100                         && (inet_ntop (AF_INET, &addr, psz_source,
1101                                         sizeof (psz_source)) == NULL))
1102                             *psz_source = '\0';
1103                         break;
1104                     }
1105                 }
1106             }
1107         }
1108
1109         if (asprintf (&p_sdp->psz_uri, "%s://%s@%s:%i", vlc_proto, psz_source,
1110                      host, port) == -1)
1111             return VLC_ENOMEM;
1112     }
1113
1114     return VLC_SUCCESS;
1115 }
1116
1117
1118 static int ParseSDPConnection (const char *str, struct sockaddr_storage *addr,
1119                                socklen_t *addrlen, unsigned *number)
1120 {
1121     char host[60];
1122     unsigned fam, n1, n2;
1123
1124     int res = sscanf (str, "IN IP%u %59[^/]/%u/%u", &fam, host, &n1, &n2);
1125     if (res < 2)
1126         return -1;
1127
1128     switch (fam)
1129     {
1130 #ifdef AF_INET6
1131         case 6:
1132             addr->ss_family = AF_INET6;
1133 # ifdef HAVE_SA_LEN
1134             addr->ss_len =
1135 # endif
1136            *addrlen = sizeof (struct sockaddr_in6);
1137
1138             if (inet_pton (AF_INET6, host,
1139                            &((struct sockaddr_in6 *)addr)->sin6_addr) <= 0)
1140                 return -1;
1141
1142             *number = (res >= 3) ? n1 : 1;
1143             break;
1144 #endif
1145
1146         case 4:
1147             addr->ss_family = AF_INET;
1148 # ifdef HAVE_SA_LEN
1149             addr->ss_len =
1150 # endif
1151            *addrlen = sizeof (struct sockaddr_in);
1152
1153             if (inet_pton (AF_INET, host,
1154                            &((struct sockaddr_in *)addr)->sin_addr) <= 0)
1155                 return -1;
1156
1157             *number = (res >= 4) ? n2 : 1;
1158             break;
1159
1160         default:
1161             return -1;
1162     }
1163     return 0;
1164 }
1165
1166
1167 /***********************************************************************
1168  * ParseSDP : SDP parsing
1169  * *********************************************************************
1170  * Validate SDP and parse all fields
1171  ***********************************************************************/
1172 static sdp_t *ParseSDP (vlc_object_t *p_obj, const char *psz_sdp)
1173 {
1174     if( psz_sdp == NULL )
1175         return NULL;
1176
1177     sdp_t *p_sdp = calloc (1, sizeof (*p_sdp));
1178     if (p_sdp == NULL)
1179         return NULL;
1180
1181     char expect = 'V';
1182     struct sockaddr_storage glob_addr;
1183     memset (&glob_addr, 0, sizeof (glob_addr));
1184     socklen_t glob_len = 0;
1185     unsigned glob_count = 1;
1186     int port = 0;
1187
1188     /* TODO: use iconv and charset attribute instead of EnsureUTF8 */
1189     while (*psz_sdp)
1190     {
1191         /* Extract one line */
1192         char *eol = strchr (psz_sdp, '\n');
1193         size_t linelen = eol ? (size_t)(eol - psz_sdp) : strlen (psz_sdp);
1194         char line[linelen + 1];
1195         memcpy (line, psz_sdp, linelen);
1196         line[linelen] = '\0';
1197
1198         psz_sdp += linelen + 1;
1199
1200         /* Remove carriage return if present */
1201         eol = strchr (line, '\r');
1202         if (eol != NULL)
1203         {
1204             linelen = eol - line;
1205             line[linelen] = '\0';
1206         }
1207
1208         /* Validate line */
1209         char cat = line[0], *data = line + 2;
1210         if (!cat || (strchr ("vosiuepcbtrzkam", cat) == NULL))
1211         {
1212             /* MUST ignore SDP with unknown line type */
1213             msg_Dbg (p_obj, "unknown SDP line type: 0x%02x", (int)cat);
1214             goto error;
1215         }
1216         if (line[1] != '=')
1217         {
1218             msg_Dbg (p_obj, "invalid SDP line: %s", line);
1219             goto error;
1220         }
1221
1222         assert (linelen >= 2);
1223
1224         /* SDP parsing state machine
1225          * We INTERNALLY use uppercase for session, lowercase for media
1226          */
1227         switch (expect)
1228         {
1229             /* Session description */
1230             case 'V':
1231                 expect = 'O';
1232                 if (cat != 'v')
1233                 {
1234                     msg_Dbg (p_obj, "missing SDP version");
1235                     goto error;
1236                 }
1237                 if (strcmp (data, "0"))
1238                 {
1239                     msg_Dbg (p_obj, "unknown SDP version: %s", data);
1240                     goto error;
1241                 }
1242                 break;
1243
1244             case 'O':
1245             {
1246                 expect = 'S';
1247                 if (cat != 'o')
1248                 {
1249                     msg_Dbg (p_obj, "missing SDP originator");
1250                     goto error;
1251                 }
1252
1253                 if ((sscanf (data, "%63s %"SCNu64" %"SCNu64" IN IP%u %1023s",
1254                              p_sdp->username, &p_sdp->session_id,
1255                              &p_sdp->session_version, &p_sdp->orig_ip_version,
1256                              p_sdp->orig_host) != 5)
1257                  || ((p_sdp->orig_ip_version != 4)
1258                   && (p_sdp->orig_ip_version != 6)))
1259                 {
1260                     msg_Dbg (p_obj, "SDP origin not supported: %s", data);
1261                     /* Or maybe out-of-range, but this looks suspicious */
1262                     goto error;
1263                 }
1264                 EnsureUTF8 (p_sdp->orig_host);
1265                 break;
1266             }
1267
1268             case 'S':
1269             {
1270                 expect = 'I';
1271                 if ((cat != 's') || !*data)
1272                 {
1273                     /* MUST be present AND non-empty */
1274                     msg_Dbg (p_obj, "missing SDP session name");
1275                     goto error;
1276                 }
1277                 assert (p_sdp->psz_sessionname == NULL); // no memleak here
1278                 p_sdp->psz_sessionname = strdup (data);
1279                 if (p_sdp->psz_sessionname == NULL)
1280                     goto error;
1281                 EnsureUTF8 (p_sdp->psz_sessionname);
1282                 break;
1283             }
1284
1285             case 'I':
1286             {
1287                 expect = 'U';
1288                 /* optional (and may be empty) */
1289                 if (cat == 'i')
1290                 {
1291                     assert (p_sdp->psz_sessioninfo == NULL);
1292                     p_sdp->psz_sessioninfo = strdup (data);
1293                     if (p_sdp->psz_sessioninfo == NULL)
1294                         goto error;
1295                     EnsureUTF8 (p_sdp->psz_sessioninfo);
1296                     break;
1297                 }
1298             }
1299
1300             case 'U':
1301                 expect = 'E';
1302                 if (cat == 'u')
1303                     break;
1304             case 'E':
1305                 expect = 'E';
1306                 if (cat == 'e')
1307                     break;
1308             case 'P':
1309                 expect = 'P';
1310                 if (cat == 'p')
1311                     break;
1312             case 'C':
1313                 expect = 'B';
1314                 if (cat == 'c')
1315                 {
1316                     if (ParseSDPConnection (data, &glob_addr, &glob_len,
1317                                             &glob_count))
1318                     {
1319                         msg_Dbg (p_obj, "SDP connection infos not supported: "
1320                                  "%s", data);
1321                         goto error;
1322                     }
1323                     break;
1324                 }
1325             case 'B':
1326                 assert (expect == 'B');
1327                 if (cat == 'b')
1328                     break;
1329             case 'T':
1330                 expect = 'R';
1331                 if (cat != 't')
1332                 {
1333                     msg_Dbg (p_obj, "missing SDP time description");
1334                     goto error;
1335                 }
1336                 break;
1337
1338             case 'R':
1339                 if ((cat == 't') || (cat == 'r'))
1340                     break;
1341
1342             case 'Z':
1343                 expect = 'K';
1344                 if (cat == 'z')
1345                     break;
1346             case 'K':
1347                 expect = 'A';
1348                 if (cat == 'k')
1349                     break;
1350             case 'A':
1351                 //expect = 'A';
1352                 if (cat == 'a')
1353                 {
1354                     attribute_t *p_attr = MakeAttribute (data);
1355                     TAB_APPEND( p_sdp->i_attributes, p_sdp->pp_attributes, p_attr );
1356                     break;
1357                 }
1358
1359             /* Media description */
1360             case 'm':
1361             media:
1362             {
1363                 expect = 'i';
1364                 if (cat != 'm')
1365                 {
1366                     msg_Dbg (p_obj, "missing SDP media description");
1367                     goto error;
1368                 }
1369                 struct sdp_media_t *m;
1370                 m = realloc (p_sdp->mediav, (p_sdp->mediac + 1) * sizeof (*m));
1371                 if (m == NULL)
1372                     goto error;
1373
1374                 p_sdp->mediav = m;
1375                 m += p_sdp->mediac;
1376                 p_sdp->mediac++;
1377
1378                 memset (m, 0, sizeof (*m));
1379                 memcpy (&m->addr, &glob_addr, m->addrlen = glob_len);
1380                 m->n_addr = glob_count;
1381
1382                 /* TODO: remember media type (if we need multiple medias) */
1383                 data = strchr (data, ' ');
1384                 if (data == NULL)
1385                 {
1386                     msg_Dbg (p_obj, "missing SDP media port");
1387                     goto error;
1388                 }
1389                 port = atoi (++data);
1390                 if (port <= 0 || port >= 65536)
1391                 {
1392                     msg_Dbg (p_obj, "invalid transport port %d", port);
1393                     goto error;
1394                 }
1395                 net_SetPort ((struct sockaddr *)&m->addr, htons (port));
1396
1397                 data = strchr (data, ' ');
1398                 if (data == NULL)
1399                 {
1400                     msg_Dbg (p_obj, "missing SDP media format");
1401                     goto error;
1402                 }
1403                 m->fmt = strdup (++data);
1404                 if (m->fmt == NULL)
1405                     goto error;
1406
1407                 break;
1408             }
1409             case 'i':
1410                 expect = 'c';
1411                 if (cat == 'i')
1412                     break;
1413             case 'c':
1414                 expect = 'b';
1415                 if (cat == 'c')
1416                 {
1417                     struct sdp_media_t *m = p_sdp->mediav + p_sdp->mediac - 1;
1418                     if (ParseSDPConnection (data, &m->addr, &m->addrlen,
1419                                             &m->n_addr))
1420                     {
1421                         msg_Dbg (p_obj, "SDP connection infos not supported: "
1422                                  "%s", data);
1423                         goto error;
1424                     }
1425                     net_SetPort ((struct sockaddr *)&m->addr, htons (port));
1426                     break;
1427                 }
1428             case 'b':
1429                 expect = 'b';
1430                 if (cat == 'b')
1431                     break;
1432             case 'k':
1433                 expect = 'a';
1434                 if (cat == 'k')
1435                     break;
1436             case 'a':
1437                 assert (expect == 'a');
1438                 if (cat == 'a')
1439                 {
1440                     attribute_t *p_attr = MakeAttribute (data);
1441                     if (p_attr == NULL)
1442                         goto error;
1443
1444                     TAB_APPEND (p_sdp->mediav[p_sdp->mediac - 1].i_attributes,
1445                                 p_sdp->mediav[p_sdp->mediac - 1].pp_attributes, p_attr);
1446                     break;
1447                 }
1448
1449                 if (cat == 'm')
1450                     goto media;
1451
1452                 msg_Dbg (p_obj, "unexpected SDP line: 0x%02x", (int)cat);
1453                 goto error;
1454
1455             default:
1456                 msg_Err (p_obj, "*** BUG in SDP parser! ***");
1457                 goto error;
1458         }
1459     }
1460
1461     return p_sdp;
1462
1463 error:
1464     FreeSDP (p_sdp);
1465     return NULL;
1466 }
1467
1468 static int InitSocket( services_discovery_t *p_sd, const char *psz_address,
1469                        int i_port )
1470 {
1471     int i_fd = net_ListenUDP1 ((vlc_object_t *)p_sd, psz_address, i_port);
1472     if (i_fd == -1)
1473         return VLC_EGENERIC;
1474
1475     shutdown( i_fd, SHUT_WR );
1476     INSERT_ELEM (p_sd->p_sys->pi_fd, p_sd->p_sys->i_fd,
1477                  p_sd->p_sys->i_fd, i_fd);
1478     return VLC_SUCCESS;
1479 }
1480
1481 static int Decompress( const unsigned char *psz_src, unsigned char **_dst, int i_len )
1482 {
1483 #ifdef HAVE_ZLIB_H
1484     int i_result, i_dstsize, n = 0;
1485     unsigned char *psz_dst = NULL;
1486     z_stream d_stream;
1487
1488     memset (&d_stream, 0, sizeof (d_stream));
1489
1490     i_result = inflateInit(&d_stream);
1491     if( i_result != Z_OK )
1492         return( -1 );
1493
1494     d_stream.next_in = (Bytef *)psz_src;
1495     d_stream.avail_in = i_len;
1496
1497     do
1498     {
1499         n++;
1500         psz_dst = (unsigned char *)realloc( psz_dst, n * 1000 );
1501         d_stream.next_out = (Bytef *)&psz_dst[(n - 1) * 1000];
1502         d_stream.avail_out = 1000;
1503
1504         i_result = inflate(&d_stream, Z_NO_FLUSH);
1505         if( ( i_result != Z_OK ) && ( i_result != Z_STREAM_END ) )
1506         {
1507             inflateEnd( &d_stream );
1508             free( psz_dst );
1509             return( -1 );
1510         }
1511     }
1512     while( ( d_stream.avail_out == 0 ) && ( d_stream.avail_in != 0 ) &&
1513            ( i_result != Z_STREAM_END ) );
1514
1515     i_dstsize = d_stream.total_out;
1516     inflateEnd( &d_stream );
1517
1518     *_dst = (unsigned char *)realloc( psz_dst, i_dstsize );
1519
1520     return i_dstsize;
1521 #else
1522     (void)psz_src;
1523     (void)_dst;
1524     (void)i_len;
1525     return -1;
1526 #endif
1527 }
1528
1529
1530 static void FreeSDP( sdp_t *p_sdp )
1531 {
1532     free( p_sdp->psz_sessionname );
1533     free( p_sdp->psz_sessioninfo );
1534     free( p_sdp->psz_uri );
1535
1536     for (unsigned j = 0; j < p_sdp->mediac; j++)
1537     {
1538         free (p_sdp->mediav[j].fmt);
1539         for (int i = 0; i < p_sdp->mediav[j].i_attributes; i++)
1540             FreeAttribute (p_sdp->mediav[j].pp_attributes[i]);
1541         free (p_sdp->mediav[j].pp_attributes);
1542     }
1543     free (p_sdp->mediav);
1544
1545     for (int i = 0; i < p_sdp->i_attributes; i++)
1546         FreeAttribute (p_sdp->pp_attributes[i]);
1547
1548     free (p_sdp->pp_attributes);
1549     free (p_sdp);
1550 }
1551
1552 static int RemoveAnnounce( services_discovery_t *p_sd,
1553                            sap_announce_t *p_announce )
1554 {
1555     int i;
1556
1557     if( p_announce->p_sdp )
1558     {
1559         FreeSDP( p_announce->p_sdp );
1560         p_announce->p_sdp = NULL;
1561     }
1562
1563     if( p_announce->p_item )
1564     {
1565         services_discovery_RemoveItem( p_sd, p_announce->p_item );
1566         vlc_gc_decref( p_announce->p_item );
1567         p_announce->p_item = NULL;
1568     }
1569
1570     for( i = 0; i< p_sd->p_sys->i_announces; i++)
1571     {
1572         if( p_sd->p_sys->pp_announces[i] == p_announce )
1573         {
1574             REMOVE_ELEM( p_sd->p_sys->pp_announces, p_sd->p_sys->i_announces,
1575                          i);
1576             break;
1577         }
1578     }
1579
1580     free( p_announce );
1581
1582     return VLC_SUCCESS;
1583 }
1584
1585 /*
1586  * Compare two sessions, when hash is not set (SAP v0)
1587  */
1588 static bool IsSameSession( sdp_t *p_sdp1, sdp_t *p_sdp2 )
1589 {
1590     /* A session is identified by
1591      * - username,
1592      * - session_id,
1593      * - network type (which is always IN),
1594      * - address type (currently, this means IP version),
1595      * - and hostname.
1596      */
1597     if (strcmp (p_sdp1->username, p_sdp2->username)
1598      || (p_sdp1->session_id != p_sdp2->session_id)
1599      || (p_sdp1->orig_ip_version != p_sdp2->orig_ip_version)
1600      || strcmp (p_sdp1->orig_host, p_sdp2->orig_host))
1601         return false;
1602
1603     return true;
1604 }
1605
1606 static inline attribute_t *MakeAttribute (const char *str)
1607 {
1608     attribute_t *a = malloc (sizeof (*a) + strlen (str) + 1);
1609     if (a == NULL)
1610         return NULL;
1611
1612     strcpy (a->name, str);
1613     EnsureUTF8 (a->name);
1614     char *value = strchr (a->name, ':');
1615     if (value != NULL)
1616     {
1617         *value++ = '\0';
1618         a->value = value;
1619     }
1620     else
1621         a->value = "";
1622     return a;
1623 }
1624
1625
1626 static const char *GetAttribute (attribute_t **tab, unsigned n,
1627                                  const char *name)
1628 {
1629     for (unsigned i = 0; i < n; i++)
1630         if (strcasecmp (tab[i]->name, name) == 0)
1631             return tab[i]->value;
1632     return NULL;
1633 }
1634
1635
1636 static inline void FreeAttribute (attribute_t *a)
1637 {
1638     free (a);
1639 }