packet-sdp.c

   1 /* packet-sdp.c
   2  * Routines for SDP packet disassembly (RFC 2327)
   3  *
   4  * Jason Lango <jal@netapp.com>
   5  * Liberally copied from packet-http.c, by Guy Harris <guy@alum.mit.edu>
   6  *
   7  * $Id: packet-sdp.c,v 1.39 2003/12/07 03:46:04 guy Exp $
   8  *
   9  * Ethereal - Network traffic analyzer
  10  * By Gerald Combs <gerald@ethereal.com>
  11  * Copyright 1998 Gerald Combs
  12  *
  13  * This program is free software; you can redistribute it and/or
  14  * modify it under the terms of the GNU General Public License
  15  * as published by the Free Software Foundation; either version 2
  16  * of the License, or (at your option) any later version.
  17  *
  18  * This program is distributed in the hope that it will be useful,
  19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  * GNU General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with this program; if not, write to the Free Software
  25  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  26  */
  27
  28 #include "config.h"
  29
  30 #include <string.h>
  31 #include <ctype.h>
  32
  33 #include <sys/types.h>
  34 #ifdef HAVE_SYS_SOCKET_H
  35 #include <sys/socket.h>
  36 #endif
  37 #ifdef HAVE_NETINET_IN_H
  38 # include <netinet/in.h>
  39 #endif
  40 #ifdef HAVE_ARPA_INET_H
  41 #include <arpa/inet.h>
  42 #endif
  43 #ifdef NEED_INET_ATON_H
  44 # include <epan/inet_aton.h>
  45 #endif
  46
  47 #include <glib.h>
  48 #include <epan/packet.h>
  49 #include <epan/conversation.h>
  50 #include <epan/strutil.h>
  51
  52 static dissector_handle_t rtp_handle=NULL;
  53 static dissector_handle_t rtcp_handle=NULL;
  54
  55 static int proto_sdp = -1;
  56
  57 /* Top level fields */
  58 static int hf_protocol_version = -1;
  59 static int hf_owner = -1;
  60 static int hf_session_name = -1;
  61 static int hf_session_info = -1;
  62 static int hf_uri = -1;
  63 static int hf_email = -1;
  64 static int hf_phone = -1;
  65 static int hf_connection_info = -1;
  66 static int hf_bandwidth = -1;
  67 static int hf_timezone = -1;
  68 static int hf_encryption_key = -1;
  69 static int hf_session_attribute = -1;
  70 static int hf_media_attribute = -1;
  71 static int hf_time = -1;
  72 static int hf_repeat_time = -1;
  73 static int hf_media = -1;
  74 static int hf_media_title = -1;
  75 static int hf_unknown = -1;
  76 static int hf_invalid = -1;
  77
  78 /* hf_owner subfields*/
  79 static int hf_owner_username = -1;
  80 static int hf_owner_sessionid = -1;
  81 static int hf_owner_version = -1;
  82 static int hf_owner_network_type = -1;
  83 static int hf_owner_address_type = -1;
  84 static int hf_owner_address = -1;
  85
  86 /* hf_connection_info subfields */
  87 static int hf_connection_info_network_type = -1;
  88 static int hf_connection_info_address_type = -1;
  89 static int hf_connection_info_connection_address = -1;
  90 static int hf_connection_info_ttl = -1;
  91 static int hf_connection_info_num_addr = -1;
  92
  93 /* hf_bandwidth subfields */
  94 static int hf_bandwidth_modifier = -1;
  95 static int hf_bandwidth_value = -1;
  96
  97 /* hf_time subfields */
  98 static int hf_time_start = -1;
  99 static int hf_time_stop = -1;
 100
 101 /* hf_repeat_time subfield */
 102 static int hf_repeat_time_interval = -1;
 103 static int hf_repeat_time_duration = -1;
 104 static int hf_repeat_time_offset = -1;
 105
 106 /* hf_timezone subfields */
 107 static int hf_timezone_time = -1;
 108 static int hf_timezone_offset = -1;
 109
 110 /* hf_encryption_key subfields */
 111 static int hf_encryption_key_type = -1;
 112 static int hf_encryption_key_data = -1;
 113
 114 /* hf_session_attribute subfields */
 115 static int hf_session_attribute_field = -1;
 116 static int hf_session_attribute_value = -1;
 117
 118 /* hf_media subfields */
 119 static int hf_media_media = -1;
 120 static int hf_media_port = -1;
 121 static int hf_media_portcount = -1;
 122 static int hf_media_proto = -1;
 123 static int hf_media_format = -1;
 124
 125 /* hf_session_attribute subfields */
 126 static int hf_media_attribute_field = -1;
 127 static int hf_media_attribute_value = -1;
 128
 129 /* trees */
 130 static int ett_sdp = -1;
 131 static int ett_sdp_owner = -1;
 132 static int ett_sdp_connection_info = -1;
 133 static int ett_sdp_bandwidth = -1;
 134 static int ett_sdp_time = -1;
 135 static int ett_sdp_repeat_time = -1;
 136 static int ett_sdp_timezone = -1;
 137 static int ett_sdp_encryption_key = -1;
 138 static int ett_sdp_session_attribute = -1;
 139 static int ett_sdp_media = -1;
 140 static int ett_sdp_media_attribute = -1;
 141
 142 typedef struct {
 143         char *media_port;
 144         char *media_proto;
 145         char *connection_address;
 146         char *connection_type;
 147 } transport_info_t;
 148
 149 /* static functions */
 150
 151 static void call_sdp_subdissector(tvbuff_t *tvb, int hf, proto_tree* ti,
 152                                   transport_info_t *transport_info);
 153
 154 /* Subdissector functions */
 155 static void dissect_sdp_owner(tvbuff_t *tvb, proto_item* ti);
 156 static void dissect_sdp_connection_info(tvbuff_t *tvb, proto_item* ti,
 157                                         transport_info_t *transport_info);
 158 static void dissect_sdp_bandwidth(tvbuff_t *tvb, proto_item *ti);
 159 static void dissect_sdp_time(tvbuff_t *tvb, proto_item* ti);
 160 static void dissect_sdp_repeat_time(tvbuff_t *tvb, proto_item* ti);
 161 static void dissect_sdp_timezone(tvbuff_t *tvb, proto_item* ti);
 162 static void dissect_sdp_encryption_key(tvbuff_t *tvb, proto_item * ti);
 163 static void dissect_sdp_session_attribute(tvbuff_t *tvb, proto_item *ti);
 164 static void dissect_sdp_media(tvbuff_t *tvb, proto_item *ti,
 165                               transport_info_t *transport_info);
 166 static void dissect_sdp_media_attribute(tvbuff_t *tvb, proto_item *ti);
 167
 168 static void
 169 dissect_sdp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 170 {
 171         proto_tree      *sdp_tree;
 172         proto_item      *ti, *sub_ti;
 173         gint            offset = 0;
 174         gint            next_offset;
 175         int             linelen;
 176         gboolean        in_media_description;
 177         guchar          type;
 178         guchar          delim;
 179         int             datalen;
 180         int             tokenoffset;
 181         int             hf = -1;
 182         char            *string;
 183
 184         address         src_addr;
 185         conversation_t  *conv=NULL;
 186
 187         transport_info_t transport_info;
 188         guint32         ipv4_address=0;
 189         guint32         ipv4_port=0;
 190         gboolean        is_rtp=FALSE;
 191         gboolean        is_ipv4_addr=FALSE;
 192         struct in_addr  ipaddr;
 193
 194         transport_info.media_port=NULL;
 195         transport_info.media_proto=NULL;
 196         transport_info.connection_address=NULL;
 197         transport_info.connection_type=NULL;
 198
 199         /*
 200          * As RFC 2327 says, "SDP is purely a format for session
 201          * description - it does not incorporate a transport protocol,
 202          * and is intended to use different transport protocols as
 203          * appropriate including the Session Announcement Protocol,
 204          * Session Initiation Protocol, Real-Time Streaming Protocol,
 205          * electronic mail using the MIME extensions, and the
 206          * Hypertext Transport Protocol."
 207          *
 208          * We therefore don't set the protocol or info columns;
 209          * instead, we append to them, so that we don't erase
 210          * what the protocol inside which the SDP stuff resides
 211          * put there.
 212          */
 213         if (check_col(pinfo->cinfo, COL_PROTOCOL))
 214                 col_append_str(pinfo->cinfo, COL_PROTOCOL, "/SDP");
 215
 216         if (check_col(pinfo->cinfo, COL_INFO)) {
 217                 /* XXX: Needs description. */
 218                 col_append_str(pinfo->cinfo, COL_INFO, ", with session description");
 219         }
 220
 221         ti = proto_tree_add_item(tree, proto_sdp, tvb, offset, -1, FALSE);
 222         sdp_tree = proto_item_add_subtree(ti, ett_sdp);
 223
 224         /*
 225          * Show the SDP message a line at a time.
 226          */
 227         in_media_description = FALSE;
 228         while (tvb_offset_exists(tvb, offset)) {
 229                 /*
 230                  * Find the end of the line.
 231                  */
 232                 linelen = tvb_find_line_end_unquoted(tvb, offset, -1,
 233                     &next_offset);
 234
 235                 /*
 236                  * Line must contain at least e.g. "v=".
 237                  */
 238                 if (linelen < 2)
 239                         break;
 240
 241                 type = tvb_get_guint8(tvb,offset);
 242                 delim = tvb_get_guint8(tvb,offset + 1);
 243                 if (delim != '=') {
 244                         proto_tree_add_item(sdp_tree,hf_invalid,tvb, offset,
 245                                               linelen, FALSE);
 246                         offset = next_offset;
 247                         continue;
 248                 }
 249
 250                 /*
 251                  * Attributes.
 252                  */
 253                 switch (type) {
 254                 case 'v':
 255                         hf = hf_protocol_version;
 256                         break;
 257                 case 'o':
 258                         hf = hf_owner;
 259                         break;
 260                 case 's':
 261                         hf = hf_session_name;
 262                         break;
 263                 case 'i':
 264                         if (in_media_description) {
 265                                 hf = hf_media_title;
 266                         }
 267                         else{
 268                                 hf = hf_session_info;
 269                         }
 270                         break;
 271                 case 'u':
 272                         hf = hf_uri;
 273                         break;
 274                 case 'e':
 275                         hf = hf_email;
 276                         break;
 277                 case 'p':
 278                         hf = hf_phone;
 279                         break;
 280                 case 'c':
 281                         hf = hf_connection_info;
 282                         break;
 283                 case 'b':
 284                         hf = hf_bandwidth;
 285                         break;
 286                 case 't':
 287                         hf = hf_time;
 288                         break;
 289                 case 'r':
 290                         hf = hf_repeat_time;
 291                         break;
 292                 case 'm':
 293                         hf = hf_media;
 294                         in_media_description = TRUE;
 295                         break;
 296                 case 'k':
 297                         hf = hf_encryption_key;
 298                         break;
 299                 case 'a':
 300                         if (in_media_description) {
 301                                 hf = hf_media_attribute;
 302                         }
 303                         else{
 304                                 hf = hf_session_attribute;
 305                         }
 306                         break;
 307                 case 'z':
 308                         hf = hf_timezone;
 309                         break;
 310                 default:
 311                         hf = hf_unknown;
 312                         break;
 313                 }
 314                 tokenoffset = 2;
 315                 if (hf == hf_unknown)
 316                         tokenoffset = 0;
 317                 string = tvb_get_string(tvb, offset + tokenoffset,
 318                     linelen - tokenoffset);
 319                 sub_ti = proto_tree_add_string_format(sdp_tree,hf,tvb, offset,
 320                                                linelen, string,
 321                                                "%s: %s",
 322                                                proto_registrar_get_name(hf),
 323                                                format_text(string,
 324                                                  linelen - tokenoffset));
 325                 g_free(string);
 326                 call_sdp_subdissector(tvb_new_subset(tvb,offset+tokenoffset,
 327                                                      linelen-tokenoffset,-1),
 328                                       hf,sub_ti,&transport_info),
 329                 offset = next_offset;
 330         }
 331
 332
 333         /* Now look, if we have strings collected.
 334          * Try to convert ipv4 address and port into binary format,
 335          * so we can use them to detect rtp and rtcp streams.
 336          * Don't forget to free the strings!
 337          */
 338
 339         if(transport_info.media_port!=NULL) {
 340                 ipv4_port = atol(transport_info.media_port);
 341                 g_free(transport_info.media_port);
 342         }
 343         if(transport_info.media_proto!=NULL) {
 344                 /* Check if media protocol is RTP */
 345                 is_rtp = (strcmp(transport_info.media_proto,"RTP/AVP")==0);
 346                 g_free(transport_info.media_proto);
 347         }
 348         if(transport_info.connection_address!=NULL) {
 349                 if(transport_info.connection_type!=NULL &&
 350                     strcmp(transport_info.connection_type,"IP4")==0) {
 351                         if(inet_aton(transport_info.connection_address, &ipaddr)
 352                             !=0 ) {
 353                                 /* connection_address could be converted to a valid ipv4 address*/
 354                                 is_ipv4_addr=TRUE;
 355                                 ipv4_address = ipaddr.s_addr;
 356                         }
 357                 }
 358                 g_free(transport_info.connection_address);
 359         }
 360         if(transport_info.connection_type!=NULL) {
 361                 g_free(transport_info.connection_type);
 362         }
 363
 364         /* Add rtp and rtcp conversation, if available */
 365         if((!pinfo->fd->flags.visited) && ipv4_address!=0 && ipv4_port!=0 && is_rtp && is_ipv4_addr){
 366                 src_addr.type=AT_IPv4;
 367                 src_addr.len=4;
 368                 src_addr.data=(char *)&ipv4_address;
 369
 370                 if(rtp_handle){
 371                         conv=find_conversation(&src_addr, &src_addr, PT_UDP, ipv4_port, ipv4_port, NO_ADDR_B|NO_PORT_B);
 372                         if(!conv){
 373                                 conv=conversation_new(&src_addr, &src_addr, PT_UDP, ipv4_port, ipv4_port, NO_ADDR_B|NO_PORT_B);
 374                                 conversation_set_dissector(conv, rtp_handle);
 375                         }
 376                 }
 377
 378                 if(rtcp_handle){
 379                         ipv4_port++;
 380                         conv=find_conversation(&src_addr, &src_addr, PT_UDP, ipv4_port, ipv4_port, NO_ADDR_B|NO_PORT_B);
 381                         if(!conv){
 382                                 conv=conversation_new(&src_addr, &src_addr, PT_UDP, ipv4_port, ipv4_port, NO_ADDR_B|NO_PORT_B);
 383                                 conversation_set_dissector(conv, rtcp_handle);
 384                         }
 385                 }
 386         }
 387
 388         datalen = tvb_length_remaining(tvb, offset);
 389         if (datalen > 0) {
 390                 proto_tree_add_text(sdp_tree, tvb, offset, datalen,
 391                     "Data (%d bytes)", datalen);
 392         }
 393 }
 394
 395 static void
 396 call_sdp_subdissector(tvbuff_t *tvb, int hf, proto_tree* ti,
 397                       transport_info_t *transport_info){
 398   if(hf == hf_owner){
 399     dissect_sdp_owner(tvb,ti);
 400   } else if ( hf == hf_connection_info) {
 401     dissect_sdp_connection_info(tvb,ti,transport_info);
 402   } else if ( hf == hf_bandwidth) {
 403     dissect_sdp_bandwidth(tvb,ti);
 404   } else if ( hf == hf_time) {
 405     dissect_sdp_time(tvb,ti);
 406   } else if ( hf == hf_repeat_time ){
 407     dissect_sdp_repeat_time(tvb,ti);
 408   } else if ( hf == hf_timezone ) {
 409     dissect_sdp_timezone(tvb,ti);
 410   } else if ( hf == hf_encryption_key ) {
 411     dissect_sdp_encryption_key(tvb,ti);
 412   } else if ( hf == hf_session_attribute ){
 413     dissect_sdp_session_attribute(tvb,ti);
 414   } else if ( hf == hf_media ) {
 415     dissect_sdp_media(tvb,ti,transport_info);
 416   } else if ( hf == hf_media_attribute ){
 417     dissect_sdp_media_attribute(tvb,ti);
 418   }
 419 }
 420
 421 static void
 422 dissect_sdp_owner(tvbuff_t *tvb, proto_item *ti){
 423   proto_tree *sdp_owner_tree;
 424   gint offset,next_offset,tokenlen;
 425
 426   offset = 0;
 427   next_offset = 0;
 428   tokenlen = 0;
 429
 430   sdp_owner_tree = proto_item_add_subtree(ti,ett_sdp_owner);
 431
 432   /* Find the username */
 433   next_offset = tvb_find_guint8(tvb,offset,-1,' ');
 434   if( next_offset == -1 )
 435     return;
 436   tokenlen = next_offset - offset;
 437
 438   proto_tree_add_item(sdp_owner_tree,hf_owner_username,tvb, offset,tokenlen,
 439                       FALSE);
 440   offset = next_offset  + 1;
 441
 442   /* Find the session id */
 443   next_offset = tvb_find_guint8(tvb,offset,-1,' ');
 444   if( next_offset == -1 )
 445     return;
 446   tokenlen = next_offset - offset;
 447
 448   proto_tree_add_item(sdp_owner_tree,hf_owner_sessionid, tvb,
 449                       offset,tokenlen,FALSE);
 450   offset = next_offset + 1;
 451
 452   /* Find the version */
 453   next_offset = tvb_find_guint8(tvb,offset,-1,' ');
 454   if( next_offset == -1 )
 455     return;
 456   tokenlen = next_offset - offset;
 457
 458   proto_tree_add_item(sdp_owner_tree,hf_owner_version, tvb,
 459                       offset,tokenlen,FALSE);
 460   offset = next_offset + 1;
 461
 462   /* Find the network type */
 463   next_offset = tvb_find_guint8(tvb,offset,-1,' ');
 464   if( next_offset == -1 )
 465     return;
 466   tokenlen = next_offset - offset;
 467
 468   proto_tree_add_item(sdp_owner_tree,hf_owner_network_type, tvb,
 469                       offset,tokenlen,FALSE);
 470   offset = next_offset + 1;
 471
 472   /* Find the address type */
 473   next_offset = tvb_find_guint8(tvb,offset,-1,' ');
 474   if( next_offset == -1 )
 475     return;
 476   tokenlen = next_offset - offset;
 477
 478   proto_tree_add_item(sdp_owner_tree,hf_owner_address_type, tvb,
 479                       offset,tokenlen,FALSE);
 480   offset = next_offset + 1;
 481
 482   /* Find the address */
 483   proto_tree_add_item(sdp_owner_tree,hf_owner_address, tvb, offset, -1, FALSE);
 484 }
 485
 486 static void
 487 dissect_sdp_connection_info(tvbuff_t *tvb, proto_item* ti,
 488                             transport_info_t *transport_info){
 489   proto_tree *sdp_connection_info_tree;
 490   gint offset,next_offset,tokenlen;
 491
 492   offset = 0;
 493   next_offset = 0;
 494   tokenlen = 0;
 495
 496   sdp_connection_info_tree = proto_item_add_subtree(ti,
 497                                                     ett_sdp_connection_info);
 498
 499   /* Find the network type */
 500   next_offset = tvb_find_guint8(tvb,offset,-1,' ');
 501   if( next_offset == -1 )
 502     return;
 503   tokenlen = next_offset - offset;
 504
 505   proto_tree_add_item(sdp_connection_info_tree,
 506                       hf_connection_info_network_type,tvb,
 507                       offset,tokenlen,FALSE);
 508   offset = next_offset + 1;
 509
 510   /* Find the address type */
 511   next_offset = tvb_find_guint8(tvb,offset,-1,' ');
 512   if( next_offset == -1 )
 513     return;
 514   tokenlen = next_offset - offset;
 515   /* Save connection address type */
 516   transport_info->connection_type = tvb_get_string(tvb, offset, tokenlen);
 517
 518   proto_tree_add_item(sdp_connection_info_tree,
 519                       hf_connection_info_address_type,tvb,
 520                       offset,tokenlen,FALSE);
 521   offset = next_offset + 1;
 522
 523   /* Find the connection address */
 524   /* XXX - what if there's a <number of addresses> value? */
 525   next_offset = tvb_find_guint8(tvb,offset,-1,'/');
 526   if( next_offset == -1){
 527     tokenlen = -1;      /* end of tvbuff */
 528     /* Save connection address */
 529     transport_info->connection_address =
 530         tvb_get_string(tvb, offset, tvb_length_remaining(tvb, offset));
 531   } else {
 532     tokenlen = next_offset - offset;
 533     /* Save connection address */
 534     transport_info->connection_address = tvb_get_string(tvb, offset, tokenlen);
 535   }
 536
 537   proto_tree_add_item(sdp_connection_info_tree,
 538                       hf_connection_info_connection_address, tvb,
 539                       offset,tokenlen,FALSE);
 540   if(next_offset != -1){
 541     offset = next_offset + 1;
 542     next_offset = tvb_find_guint8(tvb,offset,-1,'/');
 543     if( next_offset == -1){
 544       tokenlen = -1;    /* end of tvbuff */
 545     } else {
 546       tokenlen = next_offset - offset;
 547     }
 548     proto_tree_add_item(sdp_connection_info_tree,
 549                         hf_connection_info_ttl,tvb,offset,tokenlen,FALSE);
 550     if(next_offset != -1){
 551       offset = next_offset + 1;
 552       proto_tree_add_item(sdp_connection_info_tree,
 553                           hf_connection_info_num_addr, tvb,
 554                           offset, -1, FALSE);
 555     }
 556   }
 557 }
 558
 559 static void
 560 dissect_sdp_bandwidth(tvbuff_t *tvb, proto_item *ti){
 561   proto_tree * sdp_bandwidth_tree;
 562   gint offset, next_offset, tokenlen;
 563
 564   offset = 0;
 565   next_offset = 0;
 566   tokenlen = 0;
 567
 568   sdp_bandwidth_tree = proto_item_add_subtree(ti,ett_sdp_bandwidth);
 569
 570   /* find the modifier */
 571   next_offset = tvb_find_guint8(tvb,offset,-1,':');
 572
 573   if( next_offset == -1)
 574     return;
 575
 576   tokenlen = next_offset - offset;
 577
 578   proto_tree_add_item(sdp_bandwidth_tree, hf_bandwidth_modifier,
 579                       tvb, offset, tokenlen, FALSE);
 580
 581   offset = next_offset + 1;
 582
 583   proto_tree_add_item(sdp_bandwidth_tree, hf_bandwidth_value,
 584                       tvb, offset, -1, FALSE);
 585
 586 }
 587
 588 static void dissect_sdp_time(tvbuff_t *tvb, proto_item* ti){
 589   proto_tree *sdp_time_tree;
 590   gint offset,next_offset, tokenlen;
 591
 592   offset = 0;
 593   next_offset = 0;
 594   tokenlen = 0;
 595
 596   sdp_time_tree = proto_item_add_subtree(ti,ett_sdp_time);
 597
 598   /* get start time */
 599   next_offset = tvb_find_guint8(tvb,offset,-1,' ');
 600   if( next_offset == -1 )
 601     return;
 602
 603   tokenlen = next_offset - offset;
 604   proto_tree_add_item(sdp_time_tree, hf_time_start, tvb,
 605                       offset, tokenlen, FALSE);
 606
 607   /* get stop time */
 608   offset = next_offset + 1;
 609   proto_tree_add_item(sdp_time_tree,hf_time_start, tvb,
 610                       offset, -1, FALSE);
 611 }
 612
 613 static void dissect_sdp_repeat_time(tvbuff_t *tvb, proto_item* ti){
 614   proto_tree *sdp_repeat_time_tree;
 615   gint offset,next_offset, tokenlen;
 616
 617   offset = 0;
 618   next_offset = 0;
 619   tokenlen = 0;
 620
 621   sdp_repeat_time_tree = proto_item_add_subtree(ti,ett_sdp_time);
 622
 623   /* get interval */
 624   next_offset = tvb_find_guint8(tvb,offset,-1,' ');
 625   if( next_offset == -1 )
 626     return;
 627
 628   tokenlen = next_offset - offset;
 629   proto_tree_add_item(sdp_repeat_time_tree, hf_repeat_time_interval, tvb,
 630                       offset, tokenlen, FALSE);
 631
 632   /* get duration */
 633   offset = next_offset + 1;
 634   next_offset = tvb_find_guint8(tvb,offset,-1,' ');
 635   if( next_offset == -1 )
 636     return;
 637
 638   tokenlen = next_offset - offset;
 639   proto_tree_add_item(sdp_repeat_time_tree,hf_repeat_time_duration, tvb,
 640                       offset, tokenlen, FALSE);
 641
 642   /* get offsets */
 643   do{
 644     offset = next_offset +1;
 645     next_offset = tvb_find_guint8(tvb,offset,-1,' ');
 646     if(next_offset != -1){
 647       tokenlen = next_offset - offset;
 648     } else {
 649       tokenlen = -1;    /* end of tvbuff */
 650     }
 651     proto_tree_add_item(sdp_repeat_time_tree, hf_repeat_time_offset,
 652                         tvb, offset, tokenlen, FALSE);
 653   } while( next_offset != -1 );
 654
 655 }
 656 static void
 657 dissect_sdp_timezone(tvbuff_t *tvb, proto_item* ti){
 658   proto_tree* sdp_timezone_tree;
 659   gint offset, next_offset, tokenlen;
 660   offset = 0;
 661   next_offset = 0;
 662   tokenlen = 0;
 663
 664   sdp_timezone_tree = proto_item_add_subtree(ti,ett_sdp_timezone);
 665
 666   do{
 667     next_offset = tvb_find_guint8(tvb,offset,-1,' ');
 668     if(next_offset == -1)
 669       break;
 670     tokenlen = next_offset - offset;
 671
 672     proto_tree_add_item(sdp_timezone_tree,hf_timezone_time,tvb,
 673                         offset, tokenlen, FALSE);
 674     offset = next_offset + 1;
 675     next_offset = tvb_find_guint8(tvb,offset,-1,' ');
 676     if(next_offset != -1){
 677       tokenlen = next_offset - offset;
 678     } else {
 679       tokenlen = -1;    /* end of tvbuff */
 680     }
 681     proto_tree_add_item(sdp_timezone_tree,hf_timezone_offset,tvb,
 682                         offset, tokenlen, FALSE);
 683     offset = next_offset + 1;
 684   } while (next_offset != -1);
 685
 686 }
 687
 688
 689 static void dissect_sdp_encryption_key(tvbuff_t *tvb, proto_item * ti){
 690   proto_tree *sdp_encryption_key_tree;
 691   gint offset, next_offset, tokenlen;
 692
 693   offset = 0;
 694   next_offset = 0;
 695   tokenlen = 0;
 696
 697   sdp_encryption_key_tree = proto_item_add_subtree(ti,ett_sdp_encryption_key);
 698
 699   next_offset = tvb_find_guint8(tvb,offset,-1,':');
 700
 701   if(next_offset == -1)
 702     return;
 703
 704   tokenlen = next_offset - offset;
 705
 706   proto_tree_add_item(sdp_encryption_key_tree,hf_encryption_key_type,
 707                       tvb, offset, tokenlen, FALSE);
 708
 709   offset = next_offset + 1;
 710   proto_tree_add_item(sdp_encryption_key_tree,hf_encryption_key_data,
 711                       tvb, offset, -1, FALSE);
 712
 713 }
 714
 715
 716
 717 static void dissect_sdp_session_attribute(tvbuff_t *tvb, proto_item * ti){
 718   proto_tree *sdp_session_attribute_tree;
 719   gint offset, next_offset, tokenlen;
 720
 721   offset = 0;
 722   next_offset = 0;
 723   tokenlen = 0;
 724
 725   sdp_session_attribute_tree = proto_item_add_subtree(ti,
 726                                                       ett_sdp_session_attribute);
 727
 728   next_offset = tvb_find_guint8(tvb,offset,-1,':');
 729
 730   if(next_offset == -1)
 731     return;
 732
 733   tokenlen = next_offset - offset;
 734
 735   proto_tree_add_item(sdp_session_attribute_tree,
 736                       hf_session_attribute_field,
 737                       tvb, offset, tokenlen, FALSE);
 738
 739   offset = next_offset + 1;
 740   proto_tree_add_item(sdp_session_attribute_tree,
 741                       hf_session_attribute_value,
 742                       tvb, offset, -1, FALSE);
 743
 744 }
 745
 746 static void
 747 dissect_sdp_media(tvbuff_t *tvb, proto_item *ti,
 748                   transport_info_t *transport_info){
 749   proto_tree *sdp_media_tree;
 750   gint offset, next_offset, tokenlen;
 751
 752   offset = 0;
 753   next_offset = 0;
 754   tokenlen = 0;
 755
 756   sdp_media_tree = proto_item_add_subtree(ti,ett_sdp_media);
 757
 758   next_offset = tvb_find_guint8(tvb,offset, -1, ' ');
 759
 760   if(next_offset == -1)
 761     return;
 762
 763   tokenlen = next_offset - offset;
 764
 765   proto_tree_add_item(sdp_media_tree, hf_media_media, tvb,
 766                       offset, tokenlen, FALSE);
 767
 768   offset = next_offset + 1;
 769
 770   next_offset = tvb_find_guint8(tvb,offset, -1, ' ');
 771   if(next_offset == -1)
 772     return;
 773   tokenlen = next_offset - offset;
 774   next_offset = tvb_find_guint8(tvb,offset, tokenlen, '/');
 775
 776   if(next_offset != -1){
 777     tokenlen = next_offset - offset;
 778     /* Save port info */
 779     transport_info->media_port = tvb_get_string(tvb, offset, tokenlen);
 780
 781     proto_tree_add_item(sdp_media_tree, hf_media_port, tvb,
 782                         offset, tokenlen, FALSE);
 783     offset = next_offset + 1;
 784     next_offset = tvb_find_guint8(tvb,offset, -1, ' ');
 785     if(next_offset == -1)
 786       return;
 787     tokenlen = next_offset - offset;
 788     proto_tree_add_item(sdp_media_tree, hf_media_portcount, tvb,
 789                         offset, tokenlen, FALSE);
 790     offset = next_offset + 1;
 791   } else {
 792     next_offset = tvb_find_guint8(tvb,offset, -1, ' ');
 793
 794     if(next_offset == -1)
 795       return;
 796     tokenlen = next_offset - offset;
 797     /* Save port info */
 798     transport_info->media_port = tvb_get_string(tvb, offset, tokenlen);
 799
 800     /* XXX Remember Port */
 801     proto_tree_add_item(sdp_media_tree, hf_media_port, tvb,
 802                         offset, tokenlen, FALSE);
 803     offset = next_offset + 1;
 804   }
 805
 806   next_offset = tvb_find_guint8(tvb,offset,-1,' ');
 807
 808   if( next_offset == -1)
 809     return;
 810
 811   tokenlen = next_offset - offset;
 812   /* Save port protocol */
 813   transport_info->media_proto = tvb_get_string(tvb, offset, tokenlen);
 814
 815   /* XXX Remember Protocol */
 816   proto_tree_add_item(sdp_media_tree, hf_media_proto, tvb,
 817                       offset, tokenlen, FALSE);
 818
 819   do{
 820     offset = next_offset + 1;
 821     next_offset = tvb_find_guint8(tvb,offset,-1,' ');
 822
 823     if(next_offset == -1){
 824       tokenlen = -1;    /* End of tvbuff */
 825     } else {
 826       tokenlen = next_offset - offset;
 827     }
 828
 829     proto_tree_add_item(sdp_media_tree, hf_media_format, tvb,
 830                         offset, tokenlen, FALSE);
 831   } while (next_offset != -1);
 832
 833   /* XXX Dissect traffic to "Port" as "Protocol"
 834    *     Remember this Port/Protocol pair so we can tear it down again later
 835    *     Actually, it's harder than that:
 836    *         We need to find out the address of the other side first and it
 837    *         looks like that info can be found in SIP headers only.
 838    */
 839
 840 }
 841
 842 static void dissect_sdp_media_attribute(tvbuff_t *tvb, proto_item * ti){
 843   proto_tree *sdp_media_attribute_tree;
 844   gint offset, next_offset, tokenlen;
 845
 846   offset = 0;
 847   next_offset = 0;
 848   tokenlen = 0;
 849
 850   sdp_media_attribute_tree = proto_item_add_subtree(ti,
 851                                                       ett_sdp_media_attribute);
 852
 853   next_offset = tvb_find_guint8(tvb,offset,-1,':');
 854
 855   if(next_offset == -1)
 856     return;
 857
 858   tokenlen = next_offset - offset;
 859
 860   proto_tree_add_item(sdp_media_attribute_tree,
 861                       hf_media_attribute_field,
 862                       tvb, offset, tokenlen, FALSE);
 863
 864   offset = next_offset + 1;
 865   proto_tree_add_item(sdp_media_attribute_tree,
 866                       hf_media_attribute_value,
 867                       tvb, offset, -1, FALSE);
 868
 869 }
 870
 871 void
 872 proto_register_sdp(void)
 873 {
 874   static hf_register_info hf[] = {
 875     { &hf_protocol_version,
 876       { "Session Description Protocol Version (v)",
 877         "sdp.version", FT_STRING, BASE_NONE,NULL,0x0,
 878         "Session Description Protocol Version", HFILL }},
 879     { &hf_owner,
 880       { "Owner/Creator, Session Id (o)",
 881         "sdp.owner", FT_STRING, BASE_NONE, NULL, 0x0,
 882         "Owner/Creator, Session Id", HFILL}},
 883     { &hf_session_name,
 884       { "Session Name (s)",
 885         "sdp.session_name", FT_STRING, BASE_NONE,NULL, 0x0,
 886         "Session Name", HFILL }},
 887     { &hf_session_info,
 888       { "Session Information (i)",
 889         "sdp.session_info", FT_STRING, BASE_NONE, NULL, 0x0,
 890         "Session Information", HFILL }},
 891     { &hf_uri,
 892       { "URI of Description (u)",
 893         "sdp.uri", FT_STRING, BASE_NONE,NULL, 0x0,
 894         "URI of Description", HFILL }},
 895     { &hf_email,
 896       { "E-mail Address (e)",
 897         "sdp.email", FT_STRING, BASE_NONE, NULL, 0x0,
 898         "E-mail Address", HFILL }},
 899     { &hf_phone,
 900       { "Phone Number (p)",
 901         "sdp.phone", FT_STRING, BASE_NONE, NULL, 0x0,
 902         "Phone Number", HFILL }},
 903     { &hf_connection_info,
 904       { "Connection Information (c)",
 905         "sdp.connection_info", FT_STRING, BASE_NONE, NULL, 0x0,
 906         "Connection Information", HFILL }},
 907     { &hf_bandwidth,
 908       { "Bandwidth Information (b)",
 909         "sdp.bandwidth", FT_STRING, BASE_NONE, NULL, 0x0,
 910         "Bandwidth Information", HFILL }},
 911     { &hf_timezone,
 912       { "Time Zone Adjustments (z)",
 913         "sdp.timezone", FT_STRING, BASE_NONE, NULL, 0x0,
 914         "Time Zone Adjustments", HFILL }},
 915     { &hf_encryption_key,
 916       { "Encryption Key (k)",
 917         "sdp.encryption_key", FT_STRING, BASE_NONE, NULL, 0x0,
 918         "Encryption Key", HFILL }},
 919     { &hf_session_attribute,
 920       { "Session Attribute (a)",
 921         "sdp.session_attr", FT_STRING, BASE_NONE, NULL, 0x0,
 922         "Session Attribute", HFILL }},
 923     { &hf_media_attribute,
 924       { "Media Attribute (a)",
 925         "sdp.media_attr", FT_STRING, BASE_NONE, NULL, 0x0,
 926         "Media Attribute", HFILL }},
 927     { &hf_time,
 928       { "Time Description, active time (t)",
 929         "sdp.time", FT_STRING, BASE_NONE, NULL, 0x0,
 930         "Time Description, active time", HFILL }},
 931     { &hf_repeat_time,
 932       { "Repeat Time (r)",
 933         "sdp.repeat_time", FT_STRING, BASE_NONE, NULL, 0x0,
 934         "Repeat Time", HFILL }},
 935     { &hf_media,
 936       { "Media Description, name and address (m)",
 937         "sdp.media", FT_STRING, BASE_NONE, NULL, 0x0,
 938         "Media Description, name and address", HFILL }},
 939     { &hf_media_title,
 940       { "Media Title (i)",
 941         "sdp.media_title",FT_STRING, BASE_NONE, NULL, 0x0,
 942         "Media Title", HFILL }},
 943     { &hf_unknown,
 944       { "Unknown",
 945         "sdp.unknown",FT_STRING, BASE_NONE, NULL, 0x0,
 946         "Unknown", HFILL }},
 947     { &hf_invalid,
 948       { "Invalid line",
 949         "sdp.invalid",FT_STRING, BASE_NONE, NULL, 0x0,
 950         "Invalid line", HFILL }},
 951     { &hf_owner_username,
 952       { "Owner Username",
 953         "sdp.owner.username",FT_STRING, BASE_NONE, NULL, 0x0,
 954         "Owner Username", HFILL }},
 955     { &hf_owner_sessionid,
 956       { "Session ID",
 957         "sdp.owner.sessionid",FT_STRING, BASE_NONE, NULL, 0x0,
 958         "Session ID", HFILL }},
 959     { &hf_owner_version,
 960       { "Session Version",
 961         "sdp.owner.version",FT_STRING, BASE_NONE, NULL, 0x0,
 962         "Session Version", HFILL }},
 963     { &hf_owner_network_type,
 964       { "Owner Network Type",
 965         "sdp.owner.network_type",FT_STRING, BASE_NONE, NULL, 0x0,
 966         "Owner Network Type", HFILL }},
 967     { &hf_owner_address_type,
 968       { "Owner Address Type",
 969         "sdp.owner.address_type",FT_STRING, BASE_NONE, NULL, 0x0,
 970         "Owner Address Type", HFILL }},
 971     { &hf_owner_address,
 972       { "Owner Address",
 973         "sdp.owner.address",FT_STRING, BASE_NONE, NULL, 0x0,
 974         "Owner Address", HFILL }},
 975     { &hf_connection_info_network_type,
 976       { "Connection Network Type",
 977         "sdp.connection_info.network_type",FT_STRING, BASE_NONE, NULL, 0x0,
 978         "Connection Network Type", HFILL }},
 979     { &hf_connection_info_address_type,
 980       { "Connection Address Type",
 981         "sdp.connection_info.address_type",FT_STRING, BASE_NONE, NULL, 0x0,
 982         "Connection Address Type", HFILL }},
 983     { &hf_connection_info_connection_address,
 984       { "Connection Address",
 985         "sdp.connection_info.address",FT_STRING, BASE_NONE, NULL, 0x0,
 986         "Connection Address", HFILL }},
 987     { &hf_connection_info_ttl,
 988       { "Connection TTL",
 989         "sdp.connection_info.ttl",FT_STRING, BASE_NONE, NULL, 0x0,
 990         "Connection TTL", HFILL }},
 991     { &hf_connection_info_num_addr,
 992       { "Connection Number of Addresses",
 993         "sdp.connection_info.num_addr",FT_STRING, BASE_NONE, NULL, 0x0,
 994         "Connection Number of Addresses", HFILL }},
 995     { &hf_bandwidth_modifier,
 996       { "Bandwidth Modifier",
 997         "sdp.bandwidth.modifier",FT_STRING, BASE_NONE, NULL, 0x0,
 998         "Bandwidth Modifier", HFILL }},
 999     { &hf_bandwidth_value,
1000       { "Bandwidth Value",
1001         "sdp.bandwidth.value",FT_STRING, BASE_NONE, NULL, 0x0,
1002         "Bandwidth Value", HFILL }},
1003     { &hf_time_start,
1004       { "Session Start Time",
1005         "sdp.time.start",FT_STRING, BASE_NONE, NULL, 0x0,
1006         "Session Start Time", HFILL }},
1007     { &hf_time_stop,
1008       { "Session Stop Time",
1009         "sdp.time.stop",FT_STRING, BASE_NONE, NULL, 0x0,
1010         "Session Stop Time", HFILL }},
1011     { &hf_repeat_time_interval,
1012       { "Repeat Interval",
1013         "sdp.repeat_time.interval",FT_STRING, BASE_NONE, NULL, 0x0,
1014         "Repeat Interval", HFILL }},
1015     { &hf_repeat_time_duration,
1016       { "Repeat Duration",
1017         "sdp.repeat_time.duration",FT_STRING, BASE_NONE, NULL, 0x0,
1018         "Repeat Duration", HFILL }},
1019     { &hf_repeat_time_offset,
1020       { "Repeat Offset",
1021         "sdp.repeat_time.offset",FT_STRING, BASE_NONE, NULL, 0x0,
1022         "Repeat Offset", HFILL }},
1023     { &hf_timezone_time,
1024       { "Timezone Time",
1025         "sdp.timezone.time",FT_STRING, BASE_NONE, NULL, 0x0,
1026         "Timezone Time", HFILL }},
1027     { &hf_timezone_offset,
1028       { "Timezone Offset",
1029         "sdp.timezone.offset",FT_STRING, BASE_NONE, NULL, 0x0,
1030         "Timezone Offset", HFILL }},
1031     { &hf_encryption_key_type,
1032       { "Key Type",
1033         "sdp.encryption_key.type",FT_STRING, BASE_NONE, NULL, 0x0,
1034         "Type", HFILL }},
1035     { &hf_encryption_key_data,
1036       { "Key Data",
1037         "sdp.encryption_key.data",FT_STRING, BASE_NONE, NULL, 0x0,
1038         "Data", HFILL }},
1039     { &hf_session_attribute_field,
1040       { "Session Attribute Fieldname",
1041         "sdp.session_attr.field",FT_STRING, BASE_NONE, NULL, 0x0,
1042         "Session Attribute Fieldname", HFILL }},
1043     { &hf_session_attribute_value,
1044       { "Session Attribute Value",
1045         "sdp.session_attr.value",FT_STRING, BASE_NONE, NULL, 0x0,
1046         "Session Attribute Value", HFILL }},
1047     { &hf_media_media,
1048       { "Media Type",
1049         "sdp.media.media",FT_STRING, BASE_NONE, NULL, 0x0,
1050         "Media Type", HFILL }},
1051     { &hf_media_port,
1052       { "Media Port",
1053         "sdp.media.port",FT_STRING, BASE_NONE, NULL, 0x0,
1054         "Media Port", HFILL }},
1055     { &hf_media_portcount,
1056       { "Media Port Count",
1057         "sdp.media.portcount",FT_STRING, BASE_NONE, NULL, 0x0,
1058         "Media Port Count", HFILL }},
1059     { &hf_media_proto,
1060       { "Media Proto",
1061         "sdp.media.proto",FT_STRING, BASE_NONE, NULL, 0x0,
1062         "Media Proto", HFILL }},
1063     { &hf_media_format,
1064       { "Media Format",
1065         "sdp.media.format",FT_STRING, BASE_NONE, NULL, 0x0,
1066         "Media Format", HFILL }},
1067     { &hf_media_attribute_field,
1068       { "Media Attribute Fieldname",
1069         "sdp.media_attribute.field",FT_STRING, BASE_NONE, NULL, 0x0,
1070         "Media Attribute Fieldname", HFILL }},
1071     { &hf_media_attribute_value,
1072       { "Media Attribute Value",
1073         "sdp.media_attribute.value",FT_STRING, BASE_NONE, NULL, 0x0,
1074         "Media Attribute Value", HFILL }},
1075
1076   };
1077   static gint *ett[] = {
1078     &ett_sdp,
1079     &ett_sdp_owner,
1080     &ett_sdp_connection_info,
1081     &ett_sdp_bandwidth,
1082     &ett_sdp_time,
1083     &ett_sdp_repeat_time,
1084     &ett_sdp_timezone,
1085     &ett_sdp_encryption_key,
1086     &ett_sdp_session_attribute,
1087     &ett_sdp_media,
1088     &ett_sdp_media_attribute,
1089   };
1090
1091   proto_sdp = proto_register_protocol("Session Description Protocol",
1092                                       "SDP", "sdp");
1093   proto_register_field_array(proto_sdp, hf, array_length(hf));
1094   proto_register_subtree_array(ett, array_length(ett));
1095
1096   /*
1097    * Register the dissector by name, so other dissectors can
1098    * grab it by name rather than just referring to it directly
1099    * (you can't refer to it directly from a plugin dissector
1100    * on Windows without stuffing it into the Big Transfer Vector).
1101    */
1102   register_dissector("sdp", dissect_sdp, proto_sdp);
1103 }
1104
1105 void
1106 proto_reg_handoff_sdp(void)
1107 {
1108   dissector_handle_t sdp_handle;
1109
1110   rtp_handle = find_dissector("rtp");
1111   rtcp_handle = find_dissector("rtcp");
1112
1113   sdp_handle = find_dissector("sdp");
1114   dissector_add_string("media_type", "application/sdp", sdp_handle);
1115 }