modules/access/rtsp/rtsp.c

   1 /*****************************************************************************
   2  * rtsp.c: minimalistic implementation of rtsp protocol.
   3  *         Not RFC 2326 compilant yet and only handle REAL RTSP.
   4  *****************************************************************************
   5  * Copyright (C) 2002-2004 the xine project
   6  * Copyright (C) 2005 VideoLAN
   7  * $Id$
   8  *
   9  * Authors: Gildas Bazin <gbazin@videolan.org>
  10  *          Adapted from xine which itself adapted it from joschkas real tools.
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  25  *****************************************************************************/
  26
  27 #ifdef HAVE_CONFIG_H
  28 # include "config.h"
  29 #endif
  30
  31 #include <vlc_common.h>
  32
  33 #include "rtsp.h"
  34
  35 #define BUF_SIZE 4096
  36 #define HEADER_SIZE 1024
  37 #define MAX_FIELDS 256
  38
  39 struct rtsp_s {
  40
  41   int           s;
  42
  43   char         *host;
  44   int           port;
  45   char         *path;
  46   char         *mrl;
  47   char         *user_agent;
  48
  49   char         *server;
  50   unsigned int  server_state;
  51   uint32_t      server_caps;
  52
  53   unsigned int  cseq;
  54   char         *session;
  55
  56   char        *answers[MAX_FIELDS];   /* data of last message */
  57   char        *scheduled[MAX_FIELDS]; /* will be sent with next message */
  58 };
  59
  60 /*
  61  * constants
  62  */
  63
  64 const char rtsp_protocol_version[]="RTSP/1.0";
  65
  66 /* server states */
  67 #define RTSP_CONNECTED 1
  68 #define RTSP_INIT      2
  69 #define RTSP_READY     4
  70 #define RTSP_PLAYING   8
  71 #define RTSP_RECORDING 16
  72
  73 /* server capabilities */
  74 #define RTSP_OPTIONS       0x001
  75 #define RTSP_DESCRIBE      0x002
  76 #define RTSP_ANNOUNCE      0x004
  77 #define RTSP_SETUP         0x008
  78 #define RTSP_GET_PARAMETER 0x010
  79 #define RTSP_SET_PARAMETER 0x020
  80 #define RTSP_TEARDOWN      0x040
  81 #define RTSP_PLAY          0x080
  82 #define RTSP_RECORD        0x100
  83
  84 /*
  85  * rtsp_get gets a line from stream
  86  * and returns a null terminated string (must be freed).
  87  */
  88
  89 static char *rtsp_get( rtsp_client_t *rtsp )
  90 {
  91   char *psz_buffer = malloc( BUF_SIZE );
  92   char *psz_string = NULL;
  93
  94   if( rtsp->pf_read_line( rtsp->p_userdata, (uint8_t*)psz_buffer, (unsigned int)BUF_SIZE ) >= 0 )
  95   {
  96     //printf( "<< '%s'\n", psz_buffer );
  97       psz_string = strdup( psz_buffer );
  98   }
  99
 100   free( psz_buffer );
 101   return psz_string;
 102 }
 103
 104
 105 /*
 106  * rtsp_put puts a line on stream
 107  */
 108
 109 static int rtsp_put( rtsp_client_t *rtsp, const char *psz_string )
 110 {
 111     unsigned int i_buffer = strlen( psz_string );
 112     char *psz_buffer = malloc( i_buffer + 3 );
 113     int i_ret;
 114
 115     strcpy( psz_buffer, psz_string );
 116     psz_buffer[i_buffer] = '\r'; psz_buffer[i_buffer+1] = '\n';
 117     psz_buffer[i_buffer+2] = 0;
 118
 119     i_ret = rtsp->pf_write( rtsp->p_userdata, (uint8_t*)psz_buffer, i_buffer + 2 );
 120
 121     free( psz_buffer );
 122     return i_ret;
 123 }
 124
 125 /*
 126  * extract server status code
 127  */
 128
 129 static int rtsp_get_status_code( rtsp_client_t *rtsp, const char *psz_string )
 130 {
 131     VLC_UNUSED(rtsp);
 132     char psz_buffer[4];
 133     int i_code = 0;
 134
 135     if( !strncmp( psz_string, "RTSP/1.0", sizeof("RTSP/1.0") - 1 ) )
 136     {
 137         memcpy( psz_buffer, psz_string + sizeof("RTSP/1.0"), 3 );
 138         psz_buffer[3] = 0;
 139         i_code = atoi( psz_buffer );
 140     }
 141     else if( !strncmp( psz_string, "SET_PARAMETER", sizeof("SET_PARAMETER") - 1 ) )
 142     {
 143         return RTSP_STATUS_SET_PARAMETER;
 144     }
 145
 146     if( i_code != 200 )
 147     {
 148         //fprintf( stderr, "librtsp: server responds: '%s'\n", psz_string );
 149     }
 150
 151     return i_code;
 152 }
 153
 154 /*
 155  * send a request
 156  */
 157
 158 static int rtsp_send_request( rtsp_client_t *rtsp, const char *psz_type,
 159                               const char *psz_what )
 160 {
 161     char **ppsz_payload = rtsp->p_private->scheduled;
 162     char *psz_buffer;
 163     int i_ret;
 164
 165     psz_buffer = malloc( strlen(psz_type) + strlen(psz_what) +
 166                          sizeof("RTSP/1.0") + 2 );
 167
 168     sprintf( psz_buffer, "%s %s %s", psz_type, psz_what, "RTSP/1.0" );
 169     i_ret = rtsp_put( rtsp, psz_buffer );
 170     free( psz_buffer );
 171
 172     if( ppsz_payload )
 173         while( *ppsz_payload )
 174         {
 175             rtsp_put( rtsp, *ppsz_payload );
 176             ppsz_payload++;
 177         }
 178     rtsp_put( rtsp, "" );
 179     rtsp_unschedule_all( rtsp );
 180
 181     return i_ret;
 182 }
 183
 184 /*
 185  * schedule standard fields
 186  */
 187
 188 static void rtsp_schedule_standard( rtsp_client_t *rtsp )
 189 {
 190     char tmp[17];
 191
 192     sprintf( tmp, "Cseq: %u", rtsp->p_private->cseq);
 193     rtsp_schedule_field( rtsp, tmp );
 194
 195     if( rtsp->p_private->session )
 196     {
 197         char *buf;
 198         buf = malloc( strlen(rtsp->p_private->session) + 15 );
 199         sprintf( buf, "Session: %s", rtsp->p_private->session );
 200         rtsp_schedule_field( rtsp, buf );
 201         free( buf );
 202     }
 203 }
 204
 205 /*
 206  * get the answers, if server responses with something != 200, return NULL
 207  */
 208
 209 static int rtsp_get_answers( rtsp_client_t *rtsp )
 210 {
 211     char *answer = NULL;
 212     unsigned int answer_seq;
 213     char **answer_ptr = rtsp->p_private->answers;
 214     int code;
 215     int ans_count = 0;
 216
 217     answer = rtsp_get( rtsp );
 218     if( !answer ) return 0;
 219     code = rtsp_get_status_code( rtsp, answer );
 220     free( answer );
 221
 222     rtsp_free_answers( rtsp );
 223
 224     do { /* while we get answer lines */
 225
 226       answer = rtsp_get( rtsp );
 227       if( !answer ) return 0;
 228
 229       if( !strncasecmp( answer, "Cseq:", 5 ) )
 230       {
 231           sscanf( answer, "%*s %u", &answer_seq );
 232           if( rtsp->p_private->cseq != answer_seq )
 233           {
 234             //fprintf( stderr, "warning: Cseq mismatch. got %u, assumed %u",
 235             //       answer_seq, rtsp->p_private->cseq );
 236
 237               rtsp->p_private->cseq = answer_seq;
 238           }
 239       }
 240       if( !strncasecmp( answer, "Server:", 7 ) )
 241       {
 242           char *buf = malloc( strlen(answer) );
 243           sscanf( answer, "%*s %s", buf );
 244           free( rtsp->p_private->server );
 245           rtsp->p_private->server = buf;
 246       }
 247       if( !strncasecmp( answer, "Session:", 8 ) )
 248       {
 249           char *buf = malloc( strlen(answer) );
 250           sscanf( answer, "%*s %s", buf );
 251           if( rtsp->p_private->session )
 252           {
 253               if( strcmp( buf, rtsp->p_private->session ) )
 254               {
 255                   //fprintf( stderr,
 256                   //         "rtsp: warning: setting NEW session: %s\n", buf );
 257                   free( rtsp->p_private->session );
 258                   rtsp->p_private->session = strdup( buf );
 259               }
 260           }
 261           else
 262           {
 263               //fprintf( stderr, "setting session id to: %s\n", buf );
 264               rtsp->p_private->session = strdup( buf );
 265           }
 266           free( buf );
 267       }
 268
 269       *answer_ptr = answer;
 270       answer_ptr++;
 271     } while( (strlen(answer) != 0) && (++ans_count < MAX_FIELDS) );
 272
 273     rtsp->p_private->cseq++;
 274
 275     *answer_ptr = NULL;
 276     rtsp_schedule_standard( rtsp );
 277
 278     return code;
 279 }
 280
 281 /*
 282  * send an ok message
 283  */
 284
 285 int rtsp_send_ok( rtsp_client_t *rtsp )
 286 {
 287     char cseq[16];
 288
 289     rtsp_put( rtsp, "RTSP/1.0 200 OK" );
 290     sprintf( cseq, "CSeq: %u", rtsp->p_private->cseq );
 291     rtsp_put( rtsp, cseq );
 292     rtsp_put( rtsp, "" );
 293     return 0;
 294 }
 295
 296 /*
 297  * implementation of must-have rtsp requests; functions return
 298  * server status code.
 299  */
 300
 301 int rtsp_request_options( rtsp_client_t *rtsp, const char *what )
 302 {
 303     char *buf;
 304
 305     if( what ) buf = strdup(what);
 306     else
 307     {
 308         buf = malloc( strlen(rtsp->p_private->host) + 16 );
 309         sprintf( buf, "rtsp://%s:%i", rtsp->p_private->host,
 310                  rtsp->p_private->port );
 311     }
 312     rtsp_send_request( rtsp, "OPTIONS", buf );
 313     free( buf );
 314
 315     return rtsp_get_answers( rtsp );
 316 }
 317
 318 int rtsp_request_describe( rtsp_client_t *rtsp, const char *what )
 319 {
 320     char *buf;
 321
 322     if( what )
 323     {
 324         buf = strdup(what);
 325     }
 326     else
 327     {
 328         buf = malloc( strlen(rtsp->p_private->host) +
 329                       strlen(rtsp->p_private->path) + 16 );
 330         sprintf( buf, "rtsp://%s:%i/%s", rtsp->p_private->host,
 331                  rtsp->p_private->port, rtsp->p_private->path );
 332     }
 333     rtsp_send_request( rtsp, "DESCRIBE", buf );
 334     free( buf );
 335
 336     return rtsp_get_answers( rtsp );
 337 }
 338
 339 int rtsp_request_setup( rtsp_client_t *rtsp, const char *what )
 340 {
 341     rtsp_send_request( rtsp, "SETUP", what );
 342     return rtsp_get_answers( rtsp );
 343 }
 344
 345 int rtsp_request_setparameter( rtsp_client_t *rtsp, const char *what )
 346 {
 347     char *buf;
 348
 349     if( what )
 350     {
 351         buf = strdup(what);
 352     }
 353     else
 354     {
 355         buf = malloc( strlen(rtsp->p_private->host) +
 356                       strlen(rtsp->p_private->path) + 16 );
 357         sprintf( buf, "rtsp://%s:%i/%s", rtsp->p_private->host,
 358                  rtsp->p_private->port, rtsp->p_private->path );
 359     }
 360
 361     rtsp_send_request( rtsp, "SET_PARAMETER", buf );
 362     free( buf );
 363
 364     return rtsp_get_answers( rtsp );
 365 }
 366
 367 int rtsp_request_play( rtsp_client_t *rtsp, const char *what )
 368 {
 369     char *buf;
 370
 371     if( what )
 372     {
 373         buf = strdup( what );
 374     }
 375     else
 376     {
 377         buf = malloc( strlen(rtsp->p_private->host) +
 378                       strlen(rtsp->p_private->path) + 16 );
 379         sprintf( buf, "rtsp://%s:%i/%s", rtsp->p_private->host,
 380                  rtsp->p_private->port, rtsp->p_private->path );
 381     }
 382
 383     rtsp_send_request( rtsp, "PLAY", buf );
 384     free( buf );
 385
 386     return rtsp_get_answers( rtsp );
 387 }
 388
 389 int rtsp_request_tearoff( rtsp_client_t *rtsp, const char *what )
 390 {
 391     rtsp_send_request( rtsp, "TEAROFF", what );
 392     return rtsp_get_answers( rtsp );
 393 }
 394
 395 /*
 396  * read opaque data from stream
 397  */
 398
 399 int rtsp_read_data( rtsp_client_t *rtsp, uint8_t *buffer, unsigned int size )
 400 {
 401     int i, seq;
 402
 403     if( size >= 4 )
 404     {
 405         i = rtsp->pf_read( rtsp->p_userdata, (uint8_t*)buffer, (unsigned int) 4 );
 406         if( i < 4 ) return i;
 407
 408         if( buffer[0]=='S' && buffer[1]=='E' && buffer[2]=='T' &&
 409             buffer[3]=='_' )
 410         {
 411             char *rest = rtsp_get( rtsp );
 412             if( !rest ) return -1;
 413
 414             seq = -1;
 415             do
 416             {
 417                 free( rest );
 418                 rest = rtsp_get( rtsp );
 419                 if( !rest ) return -1;
 420
 421                 if( !strncasecmp( rest, "Cseq:", 5 ) )
 422                     sscanf( rest, "%*s %u", &seq );
 423             } while( *rest );
 424             free( rest );
 425
 426             if( seq < 0 )
 427             {
 428                 //fprintf(stderr, "warning: cseq not recognized!\n");
 429                 seq = 1;
 430             }
 431
 432             /* lets make the server happy */
 433             rtsp_put( rtsp, "RTSP/1.0 451 Parameter Not Understood" );
 434             rest = malloc(17);
 435             sprintf( rest,"CSeq: %u", seq );
 436             rtsp_put( rtsp, rest );
 437             rtsp_put( rtsp, "" );
 438             free( rest );
 439             i = rtsp->pf_read( rtsp->p_userdata, (unsigned char*)buffer, size );
 440         }
 441         else
 442         {
 443             i = rtsp->pf_read( rtsp->p_userdata, (unsigned char*)buffer + 4, size - 4 );
 444             i += 4;
 445         }
 446     }
 447     else i = rtsp->pf_read( rtsp->p_userdata, (unsigned char*)buffer, size );
 448
 449     //fprintf( stderr, "<< %d of %d bytes\n", i, size );
 450
 451     return i;
 452 }
 453
 454 /*
 455  * connect to a rtsp server
 456  */
 457
 458 int rtsp_connect( rtsp_client_t *rtsp, const char *psz_mrl,
 459                   const char *psz_user_agent )
 460 {
 461     rtsp_t *s;
 462     char *mrl_ptr;
 463     char *slash, *colon;
 464     unsigned int hostend, pathbegin, i;
 465
 466     if( !psz_mrl ) return -1;
 467     s = malloc( sizeof(rtsp_t) );
 468     rtsp->p_private = s;
 469
 470     if( !strncmp( psz_mrl, "rtsp://", 7 ) ) psz_mrl += 7;
 471     mrl_ptr = strdup( psz_mrl );
 472
 473     for( i=0; i<MAX_FIELDS; i++ )
 474     {
 475         s->answers[i]=NULL;
 476         s->scheduled[i]=NULL;
 477     }
 478
 479     s->host = NULL;
 480     s->port = 554; /* rtsp standard port */
 481     s->path = NULL;
 482     s->mrl  = strdup(psz_mrl);
 483
 484     s->server = NULL;
 485     s->server_state = 0;
 486     s->server_caps = 0;
 487
 488     s->cseq = 0;
 489     s->session = NULL;
 490
 491     if( psz_user_agent ) s->user_agent = strdup( psz_user_agent );
 492     else s->user_agent = strdup( "User-Agent: RealMedia Player Version "
 493                                  "6.0.9.1235 (linux-2.0-libc6-i386-gcc2.95)" );
 494
 495     slash = strchr( mrl_ptr, '/' );
 496     colon = strchr( mrl_ptr, ':' );
 497
 498     if( !slash ) slash = mrl_ptr + strlen(mrl_ptr) + 1;
 499     if( !colon ) colon = slash;
 500     if( colon > slash ) colon = slash;
 501
 502     pathbegin = slash - mrl_ptr;
 503     hostend = colon - mrl_ptr;
 504
 505     s->host = malloc(hostend+1);
 506     strncpy( s->host, mrl_ptr, hostend );
 507     s->host[hostend] = 0;
 508
 509     if( pathbegin < strlen(mrl_ptr) ) s->path = strdup(mrl_ptr+pathbegin+1);
 510     if( colon != slash )
 511     {
 512         char buffer[pathbegin-hostend];
 513
 514         strncpy( buffer, mrl_ptr+hostend+1, pathbegin-hostend-1 );
 515         buffer[pathbegin-hostend-1] = 0;
 516         s->port = atoi(buffer);
 517         if( s->port < 0 || s->port > 65535 ) s->port = 554;
 518     }
 519
 520     free( mrl_ptr );
 521     //fprintf( stderr, "got mrl: %s %i %s\n", s->host, s->port, s->path );
 522
 523     s->s = rtsp->pf_connect( rtsp->p_userdata, s->host, s->port );
 524
 525     if( s->s < 0 )
 526     {
 527         //fprintf(stderr, "rtsp: failed to connect to '%s'\n", s->host);
 528         rtsp_close( rtsp );
 529         return -1;
 530     }
 531
 532     s->server_state = RTSP_CONNECTED;
 533
 534     /* now lets send an options request. */
 535     rtsp_schedule_field( rtsp, "CSeq: 1");
 536     rtsp_schedule_field( rtsp, s->user_agent);
 537     rtsp_schedule_field( rtsp, "ClientChallenge: "
 538                                "9e26d33f2984236010ef6253fb1887f7");
 539     rtsp_schedule_field( rtsp, "PlayerStarttime: [28/03/2003:22:50:23 00:00]");
 540     rtsp_schedule_field( rtsp, "CompanyID: KnKV4M4I/B2FjJ1TToLycw==" );
 541     rtsp_schedule_field( rtsp, "GUID: 00000000-0000-0000-0000-000000000000" );
 542     rtsp_schedule_field( rtsp, "RegionData: 0" );
 543     rtsp_schedule_field( rtsp, "ClientID: "
 544                                "Linux_2.4_6.0.9.1235_play32_RN01_EN_586" );
 545     /*rtsp_schedule_field( rtsp, "Pragma: initiate-session" );*/
 546     rtsp_request_options( rtsp, NULL );
 547
 548     return 0;
 549 }
 550
 551 /*
 552  * closes an rtsp connection
 553  */
 554
 555 void rtsp_close( rtsp_client_t *rtsp )
 556 {
 557     if( rtsp->p_private->server_state )
 558     {
 559         /* TODO: send a TEAROFF */
 560         rtsp->pf_disconnect( rtsp->p_userdata );
 561     }
 562
 563     free( rtsp->p_private->path );
 564     free( rtsp->p_private->host );
 565     free( rtsp->p_private->mrl );
 566     free( rtsp->p_private->session );
 567     free( rtsp->p_private->user_agent );
 568     free( rtsp->p_private->server );
 569     rtsp_free_answers( rtsp );
 570     rtsp_unschedule_all( rtsp );
 571     free( rtsp->p_private );
 572 }
 573
 574 /*
 575  * search in answers for tags. returns a pointer to the content
 576  * after the first matched tag. returns NULL if no match found.
 577  */
 578
 579 char *rtsp_search_answers( rtsp_client_t *rtsp, const char *tag )
 580 {
 581     char **answer;
 582     char *ptr;
 583
 584     if( !rtsp->p_private->answers ) return NULL;
 585     answer = rtsp->p_private->answers;
 586
 587     while(*answer)
 588     {
 589         if( !strncasecmp( *answer, tag, strlen(tag) ) )
 590         {
 591             ptr = strchr(*answer, ':');
 592             ptr++;
 593             while( *ptr == ' ' ) ptr++;
 594             return ptr;
 595         }
 596         answer++;
 597     }
 598
 599     return NULL;
 600 }
 601
 602 /*
 603  * session id management
 604  */
 605
 606 void rtsp_set_session( rtsp_client_t *rtsp, const char *id )
 607 {
 608     free( rtsp->p_private->session );
 609     rtsp->p_private->session = strdup(id);
 610 }
 611
 612 char *rtsp_get_session( rtsp_client_t *rtsp )
 613 {
 614     return rtsp->p_private->session;
 615 }
 616
 617 char *rtsp_get_mrl( rtsp_client_t *rtsp )
 618 {
 619     return rtsp->p_private->mrl;
 620 }
 621
 622 /*
 623  * schedules a field for transmission
 624  */
 625
 626 void rtsp_schedule_field( rtsp_client_t *rtsp, const char *string )
 627 {
 628     int i = 0;
 629
 630     if( !string ) return;
 631
 632     while( rtsp->p_private->scheduled[i] ) i++;
 633
 634     rtsp->p_private->scheduled[i] = strdup(string);
 635 }
 636
 637 /*
 638  * removes the first scheduled field which prefix matches string.
 639  */
 640
 641 void rtsp_unschedule_field( rtsp_client_t *rtsp, const char *string )
 642 {
 643     char **ptr = rtsp->p_private->scheduled;
 644
 645     if( !string ) return;
 646
 647     while( *ptr )
 648     {
 649       if( !strncmp(*ptr, string, strlen(string)) ) break;
 650     }
 651     free( *ptr );
 652     ptr++;
 653     do
 654     {
 655         *(ptr-1) = *ptr;
 656     } while( *ptr );
 657 }
 658
 659 /*
 660  * unschedule all fields
 661  */
 662
 663 void rtsp_unschedule_all( rtsp_client_t *rtsp )
 664 {
 665     char **ptr;
 666
 667     if( !rtsp->p_private->scheduled ) return;
 668     ptr = rtsp->p_private->scheduled;
 669
 670     while( *ptr )
 671     {
 672         free( *ptr );
 673         *ptr = NULL;
 674         ptr++;
 675     }
 676 }
 677 /*
 678  * free answers
 679  */
 680
 681 void rtsp_free_answers( rtsp_client_t *rtsp )
 682 {
 683     char **answer;
 684
 685     if( !rtsp->p_private->answers ) return;
 686     answer = rtsp->p_private->answers;
 687
 688     while( *answer )
 689     {
 690         free( *answer );
 691         *answer = NULL;
 692         answer++;
 693     }
 694 }