epan/dissectors/packet-rtp.c

   1 /* packet-rtp.c
   2  *
   3  * Routines for RTP dissection
   4  * RTP = Real time Transport Protocol
   5  *
   6  * Copyright 2000, Philips Electronics N.V.
   7  * Written by Andreas Sikkema <h323@ramdyne.nl>
   8  *
   9  * $Id$
  10  *
  11  * Wireshark - Network traffic analyzer
  12  * By Gerald Combs <gerald@wireshark.org>
  13  * Copyright 1998 Gerald Combs
  14  *
  15  * This program is free software; you can redistribute it and/or
  16  * modify it under the terms of the GNU General Public License
  17  * as published by the Free Software Foundation; either version 2
  18  * of the License, or (at your option) any later version.
  19  *
  20  * This program is distributed in the hope that it will be useful,
  21  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  22  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  23  * GNU General Public License for more details.
  24  *
  25  * You should have received a copy of the GNU General Public License
  26  * along with this program; if not, write to the Free Software
  27  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  28  */
  29
  30 /*
  31  * This dissector tries to dissect the RTP protocol according to Annex A
  32  * of ITU-T Recommendation H.225.0 (02/98) or RFC 1889
  33  *
  34  * RTP traffic is handled by an even UDP portnumber. This can be any
  35  * port number, but there is a registered port available, port 5004
  36  * See Annex B of ITU-T Recommendation H.225.0, section B.7
  37  *
  38  * This doesn't dissect older versions of RTP, such as:
  39  *
  40  *    the vat protocol ("version 0") - see
  41  *
  42  *      ftp://ftp.ee.lbl.gov/conferencing/vat/alpha-test/vatsrc-4.0b2.tar.gz
  43  *
  44  *    and look in "session-vat.cc" if you want to write a dissector
  45  *    (have fun - there aren't any nice header files showing the packet
  46  *    format);
  47  *
  48  *    version 1, as documented in
  49  *
  50  *      ftp://gaia.cs.umass.edu/pub/hgschulz/rtp/draft-ietf-avt-rtp-04.txt
  51  *
  52  * It also dissects PacketCable CCC-encapsulated RTP data, as described in
  53  * chapter 5 of the PacketCable Electronic Surveillance Specification:
  54  *
  55  *   http://www.packetcable.com/downloads/specs/PKT-SP-ESP1.5-I01-050128.pdf
  56  */
  57
  58
  59 #ifdef HAVE_CONFIG_H
  60 # include "config.h"
  61 #endif
  62
  63 #include <glib.h>
  64 #include <epan/packet.h>
  65
  66 #include <stdio.h>
  67 #include <string.h>
  68
  69 #include "packet-rtp.h"
  70 #include <epan/rtp_pt.h>
  71 #include "packet-ntp.h"
  72 #include <epan/conversation.h>
  73 #include <epan/reassemble.h>
  74 #include <epan/tap.h>
  75
  76 #include <epan/prefs.h>
  77 #include <epan/emem.h>
  78 #include <epan/strutil.h>
  79
  80 /* uncomment this to enable debugging of fragment reassembly */
  81 /* #define DEBUG_FRAGMENTS   1 */
  82
  83 typedef struct _rfc2198_hdr {
  84   unsigned int pt;
  85   int offset;
  86   int len;
  87   struct _rfc2198_hdr *next;
  88 } rfc2198_hdr;
  89
  90 /* we have one of these for each pdu which spans more than one segment
  91  */
  92 typedef struct _rtp_multisegment_pdu {
  93         /* the seqno of the segment where the pdu starts */
  94         guint32 startseq;
  95
  96         /* the seqno of the segment where the pdu ends */
  97         guint32 endseq;
  98 } rtp_multisegment_pdu;
  99
 100 typedef struct  _rtp_private_conv_info {
 101         /* This tree is indexed by sequence number and keeps track of all
 102          * all pdus spanning multiple segments for this flow.
 103          */
 104         emem_tree_t *multisegment_pdus;
 105 } rtp_private_conv_info;
 106
 107 static GHashTable *fragment_table = NULL;
 108 static GHashTable * fid_table = NULL;
 109
 110 static int hf_rtp_fragments = -1;
 111 static int hf_rtp_fragment = -1;
 112 static int hf_rtp_fragment_overlap = -1;
 113 static int hf_rtp_fragment_overlap_conflict = -1;
 114 static int hf_rtp_fragment_multiple_tails = -1;
 115 static int hf_rtp_fragment_too_long_fragment = -1;
 116 static int hf_rtp_fragment_error = -1;
 117 static int hf_rtp_reassembled_in = -1;
 118
 119 static gint ett_rtp_fragment = -1;
 120 static gint ett_rtp_fragments = -1;
 121
 122 static const fragment_items rtp_fragment_items = {
 123   &ett_rtp_fragment,
 124   &ett_rtp_fragments,
 125   &hf_rtp_fragments,
 126   &hf_rtp_fragment,
 127   &hf_rtp_fragment_overlap,
 128   &hf_rtp_fragment_overlap_conflict,
 129   &hf_rtp_fragment_multiple_tails,
 130   &hf_rtp_fragment_too_long_fragment,
 131   &hf_rtp_fragment_error,
 132   &hf_rtp_reassembled_in,
 133   "RTP fragments"
 134 };
 135
 136 static dissector_handle_t rtp_handle;
 137 static dissector_handle_t stun_handle;
 138 static dissector_handle_t stun_heur_handle;
 139 static dissector_handle_t t38_handle;
 140 static dissector_handle_t zrtp_handle;
 141
 142 static int rtp_tap = -1;
 143
 144 static dissector_table_t rtp_pt_dissector_table;
 145 static dissector_table_t rtp_dyn_pt_dissector_table;
 146
 147 static dissector_table_t rtp_hdr_ext_dissector_table;
 148
 149 /* RTP header fields             */
 150 static int proto_rtp           = -1;
 151 static int hf_rtp_version      = -1;
 152 static int hf_rtp_padding      = -1;
 153 static int hf_rtp_extension    = -1;
 154 static int hf_rtp_csrc_count   = -1;
 155 static int hf_rtp_marker       = -1;
 156 static int hf_rtp_payload_type = -1;
 157 static int hf_rtp_seq_nr       = -1;
 158 static int hf_rtp_ext_seq_nr   = -1;
 159 static int hf_rtp_timestamp    = -1;
 160 static int hf_rtp_ssrc         = -1;
 161 static int hf_rtp_csrc_items   = -1;
 162 static int hf_rtp_csrc_item    = -1;
 163 static int hf_rtp_data         = -1;
 164 static int hf_rtp_padding_data = -1;
 165 static int hf_rtp_padding_count= -1;
 166 static int hf_rtp_rfc2198_follow= -1;
 167 static int hf_rtp_rfc2198_tm_off= -1;
 168 static int hf_rtp_rfc2198_bl_len= -1;
 169
 170 /* RTP header extension fields   */
 171 static int hf_rtp_prof_define  = -1;
 172 static int hf_rtp_length       = -1;
 173 static int hf_rtp_hdr_exts     = -1;
 174 static int hf_rtp_hdr_ext      = -1;
 175
 176 /* RTP setup fields */
 177 static int hf_rtp_setup        = -1;
 178 static int hf_rtp_setup_frame  = -1;
 179 static int hf_rtp_setup_method = -1;
 180
 181 /* RTP fields defining a sub tree */
 182 static gint ett_rtp       = -1;
 183 static gint ett_csrc_list = -1;
 184 static gint ett_hdr_ext   = -1;
 185 static gint ett_rtp_setup = -1;
 186 static gint ett_rtp_rfc2198 = -1;
 187 static gint ett_rtp_rfc2198_hdr = -1;
 188
 189 /* SRTP fields */
 190 static int hf_srtp_encrypted_payload = -1;
 191 static int hf_srtp_mki = -1;
 192 static int hf_srtp_auth_tag = -1;
 193
 194 /* PacketCable CCC header fields */
 195 static int proto_pkt_ccc       = -1;
 196 static int hf_pkt_ccc_id       = -1;
 197 static int hf_pkt_ccc_ts       = -1;
 198
 199 /* PacketCable CCC field defining a sub tree */
 200 static gint ett_pkt_ccc = -1;
 201
 202 /* PacketCable CCC port preference */
 203 static guint global_pkt_ccc_udp_port = 0;
 204
 205
 206 #define RTP0_INVALID 0
 207 #define RTP0_STUN    1
 208 #define RTP0_T38     2
 209
 210 static enum_val_t rtp_version0_types[] = {
 211         { "invalid", "Invalid or ZRTP packets", RTP0_INVALID },
 212         { "stun", "STUN packets", RTP0_STUN },
 213         { "t38", "T.38 packets", RTP0_T38 },
 214         { NULL, NULL, 0 }
 215 };
 216 static gint global_rtp_version0_type = 0;
 217
 218 static dissector_handle_t data_handle;
 219
 220 /* Forward declaration we need below */
 221 void proto_reg_handoff_rtp(void);
 222 void proto_reg_handoff_pkt_ccc(void);
 223
 224 static gboolean dissect_rtp_heur( tvbuff_t *tvb, packet_info *pinfo,
 225     proto_tree *tree );
 226 static void dissect_rtp( tvbuff_t *tvb, packet_info *pinfo,
 227     proto_tree *tree );
 228 static void show_setup_info(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree);
 229 static void get_conv_info(packet_info *pinfo, struct _rtp_info *rtp_info);
 230
 231 /* Preferences bool to control whether or not setup info should be shown */
 232 static gboolean global_rtp_show_setup_info = TRUE;
 233
 234 /* Try heuristic RTP decode */
 235 static gboolean global_rtp_heur = FALSE;
 236
 237 /* desegment RTP streams */
 238 static gboolean desegment_rtp = TRUE;
 239
 240 /* RFC2198 Redundant Audio Data */
 241 static guint rtp_rfc2198_pt = 99;
 242
 243 /*
 244  * Fields in the first octet of the RTP header.
 245  */
 246
 247 /* Version is the first 2 bits of the first octet*/
 248 #define RTP_VERSION(octet)      ((octet) >> 6)
 249
 250 /* Padding is the third bit; No need to shift, because true is any value
 251    other than 0! */
 252 #define RTP_PADDING(octet)      ((octet) & 0x20)
 253
 254 /* Extension bit is the fourth bit */
 255 #define RTP_EXTENSION(octet)    ((octet) & 0x10)
 256
 257 /* CSRC count is the last four bits */
 258 #define RTP_CSRC_COUNT(octet)   ((octet) & 0xF)
 259
 260 static const value_string rtp_version_vals[] =
 261 {
 262         { 0, "Old VAT Version" },
 263         { 1, "First Draft Version" },
 264         { 2, "RFC 1889 Version" },
 265         { 0, NULL },
 266 };
 267
 268 /*
 269  * Fields in the second octet of the RTP header.
 270  */
 271
 272 /* Marker is the first bit of the second octet */
 273 #define RTP_MARKER(octet)       ((octet) & 0x80)
 274
 275 /* Payload type is the last 7 bits */
 276 #define RTP_PAYLOAD_TYPE(octet) ((octet) & 0x7F)
 277
 278 const value_string rtp_payload_type_vals[] =
 279 {
 280         { PT_PCMU,      "ITU-T G.711 PCMU" },
 281         { PT_1016,      "USA Federal Standard FS-1016" },
 282         { PT_G721,      "ITU-T G.721" },
 283         { PT_GSM,       "GSM 06.10" },
 284         { PT_G723,      "ITU-T G.723" },
 285         { PT_DVI4_8000, "DVI4 8000 samples/s" },
 286         { PT_DVI4_16000, "DVI4 16000 samples/s" },
 287         { PT_LPC,       "Experimental linear predictive encoding from Xerox PARC" },
 288         { PT_PCMA,      "ITU-T G.711 PCMA" },
 289         { PT_G722,      "ITU-T G.722" },
 290         { PT_L16_STEREO, "16-bit uncompressed audio, stereo" },
 291         { PT_L16_MONO,  "16-bit uncompressed audio, monaural" },
 292         { PT_QCELP,     "Qualcomm Code Excited Linear Predictive coding" },
 293         { PT_CN,        "Comfort noise" },
 294         { PT_MPA,       "MPEG-I/II Audio"},
 295         { PT_G728,      "ITU-T G.728" },
 296         { PT_DVI4_11025, "DVI4 11025 samples/s" },
 297         { PT_DVI4_22050, "DVI4 22050 samples/s" },
 298         { PT_G729,      "ITU-T G.729" },
 299         { PT_CN_OLD,    "Comfort noise (old)" },
 300         { PT_CELB,      "Sun CellB video encoding" },
 301         { PT_JPEG,      "JPEG-compressed video" },
 302         { PT_NV,        "'nv' program" },
 303         { PT_H261,      "ITU-T H.261" },
 304         { PT_MPV,       "MPEG-I/II Video"},
 305         { PT_MP2T,      "MPEG-II transport streams"},
 306         { PT_H263,      "ITU-T H.263" },
 307         { 0,            NULL },
 308 };
 309
 310 const value_string rtp_payload_type_short_vals[] =
 311 {
 312        { PT_PCMU,      "g711U" },
 313        { PT_1016,      "fs-1016" },
 314        { PT_G721,      "g721" },
 315        { PT_GSM,       "GSM" },
 316        { PT_G723,      "g723" },
 317        { PT_DVI4_8000, "DVI4 8k" },
 318        { PT_DVI4_16000, "DVI4 16k" },
 319        { PT_LPC,       "Exp. from Xerox PARC" },
 320        { PT_PCMA,      "g711A" },
 321        { PT_G722,      "g722" },
 322        { PT_L16_STEREO, "16-bit audio, stereo" },
 323        { PT_L16_MONO,  "16-bit audio, monaural" },
 324        { PT_QCELP,     "Qualcomm" },
 325        { PT_CN,        "CN" },
 326        { PT_MPA,       "MPEG-I/II Audio"},
 327        { PT_G728,      "g728" },
 328        { PT_DVI4_11025, "DVI4 11k" },
 329        { PT_DVI4_22050, "DVI4 22k" },
 330        { PT_G729,      "g729" },
 331        { PT_CN_OLD,    "CN(old)" },
 332        { PT_CELB,      "CellB" },
 333        { PT_JPEG,      "JPEG" },
 334        { PT_NV,        "NV" },
 335        { PT_H261,      "h261" },
 336        { PT_MPV,       "MPEG-I/II Video"},
 337        { PT_MP2T,      "MPEG-II streams"},
 338        { PT_H263,      "h263" },
 339        { 0,            NULL },
 340 };
 341 #if 0
 342 static const value_string srtp_encryption_alg_vals[] =
 343 {
 344         { SRTP_ENC_ALG_NULL,    "Null Encryption" },
 345         { SRTP_ENC_ALG_AES_CM, "AES-128 Counter Mode" },
 346         { SRTP_ENC_ALG_AES_F8,  "AES-128 F8 Mode" },
 347         { 0, NULL },
 348 };
 349
 350 static const value_string srtp_auth_alg_vals[] =
 351 {
 352         { SRTP_AUTH_ALG_NONE,           "No Authentication" },
 353         { SRTP_AUTH_ALG_HMAC_SHA1,      "HMAC-SHA1" },
 354         { 0, NULL },
 355 };
 356 #endif
 357
 358 /* initialisation routine */
 359 static void rtp_fragment_init(void)
 360 {
 361         fragment_table_init(&fragment_table);
 362         fid_table = g_hash_table_new(g_direct_hash, g_direct_equal);
 363 }
 364
 365 void
 366 rtp_free_hash_dyn_payload(GHashTable *rtp_dyn_payload)
 367 {
 368         if (rtp_dyn_payload == NULL) return;
 369         g_hash_table_destroy(rtp_dyn_payload);
 370         rtp_dyn_payload = NULL;
 371 }
 372
 373 /* Set up an SRTP conversation */
 374 void srtp_add_address(packet_info *pinfo,
 375                      address *addr, int port,
 376                      int other_port,
 377                      const gchar *setup_method, guint32 setup_frame_number, GHashTable *rtp_dyn_payload,
 378                      struct srtp_info *srtp_info)
 379 {
 380         address null_addr;
 381         conversation_t* p_conv;
 382         struct _rtp_conversation_info *p_conv_data = NULL;
 383
 384         /*
 385          * If this isn't the first time this packet has been processed,
 386          * we've already done this work, so we don't need to do it
 387          * again.
 388          */
 389         if (pinfo->fd->flags.visited)
 390         {
 391                 return;
 392         }
 393
 394 #ifdef DEBUG
 395         printf("#%u: %srtp_add_address(%s, %u, %u, %s, %u\n", pinfo->fd->num, (srtp_info)?"s":"", address_to_str(addr), port, other_port, setup_method, setup_frame_number);
 396 #endif
 397
 398         SET_ADDRESS(&null_addr, AT_NONE, 0, NULL);
 399
 400         /*
 401          * Check if the ip address and port combination is not
 402          * already registered as a conversation.
 403          */
 404         p_conv = find_conversation( setup_frame_number, addr, &null_addr, PT_UDP, port, other_port,
 405                                 NO_ADDR_B | (!other_port ? NO_PORT_B : 0));
 406
 407         /*
 408          * If not, create a new conversation.
 409          */
 410         if ( !p_conv || p_conv->setup_frame != setup_frame_number) {
 411                 p_conv = conversation_new( setup_frame_number, addr, &null_addr, PT_UDP,
 412                                            (guint32)port, (guint32)other_port,
 413                                                                    NO_ADDR2 | (!other_port ? NO_PORT2 : 0));
 414         }
 415
 416         /* Set dissector */
 417         conversation_set_dissector(p_conv, rtp_handle);
 418
 419         /*
 420          * Check if the conversation has data associated with it.
 421          */
 422         p_conv_data = conversation_get_proto_data(p_conv, proto_rtp);
 423
 424         /*
 425          * If not, add a new data item.
 426          */
 427         if ( ! p_conv_data ) {
 428                 /* Create conversation data */
 429                 p_conv_data = se_alloc(sizeof(struct _rtp_conversation_info));
 430                 p_conv_data->rtp_dyn_payload = NULL;
 431
 432                 /* start this at 0x10000 so that we cope gracefully with the
 433                  * first few packets being out of order (hence 0,65535,1,2,...)
 434                  */
 435                 p_conv_data->extended_seqno = 0x10000;
 436                 p_conv_data->rtp_conv_info = se_alloc(sizeof(rtp_private_conv_info));
 437                 p_conv_data->rtp_conv_info->multisegment_pdus = se_tree_create(EMEM_TREE_TYPE_RED_BLACK,"rtp_ms_pdus");
 438                 conversation_add_proto_data(p_conv, proto_rtp, p_conv_data);
 439         }
 440
 441         /*
 442          * Update the conversation data.
 443          */
 444         /* Free the hash if already exists */
 445         rtp_free_hash_dyn_payload(p_conv_data->rtp_dyn_payload);
 446
 447         g_strlcpy(p_conv_data->method, setup_method, MAX_RTP_SETUP_METHOD_SIZE);
 448         p_conv_data->frame_number = setup_frame_number;
 449         p_conv_data->rtp_dyn_payload = rtp_dyn_payload;
 450         p_conv_data->srtp_info = srtp_info;
 451 }
 452
 453 /* Set up an RTP conversation */
 454 void rtp_add_address(packet_info *pinfo,
 455                      address *addr, int port,
 456                      int other_port,
 457                      const gchar *setup_method, guint32 setup_frame_number, GHashTable *rtp_dyn_payload)
 458 {
 459         srtp_add_address(pinfo, addr, port, other_port, setup_method, setup_frame_number, rtp_dyn_payload, NULL);
 460 }
 461
 462 static gboolean
 463 dissect_rtp_heur( tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree )
 464 {
 465         guint8      octet1, octet2;
 466         unsigned int version;
 467         unsigned int payload_type;
 468         unsigned int offset = 0;
 469
 470         /* This is a heuristic dissector, which means we get all the UDP
 471          * traffic not sent to a known dissector and not claimed by
 472          * a heuristic dissector called before us!
 473          */
 474
 475         if (! global_rtp_heur)
 476                 return FALSE;
 477
 478         /* Get the fields in the first octet */
 479         octet1 = tvb_get_guint8( tvb, offset );
 480         version = RTP_VERSION( octet1 );
 481
 482         if (version == 0) {
 483                 if (!(tvb_memeql(tvb, 4, "ZRTP", 4)))
 484                 {
 485                         call_dissector_only(zrtp_handle, tvb, pinfo, tree);
 486                         return TRUE;
 487                 } else {
 488                         switch (global_rtp_version0_type) {
 489                         case RTP0_STUN:
 490                                 return call_dissector_only(stun_heur_handle, tvb, pinfo, tree);
 491
 492                         case RTP0_T38:
 493                                 /* XXX: Should really be calling a heuristic dissector for T38 ??? */
 494                                 call_dissector_only(t38_handle, tvb, pinfo, tree);
 495                                 return TRUE;
 496
 497                         case RTP0_INVALID:
 498
 499                         default:
 500                                 return FALSE; /* Unknown or unsupported version */
 501                         }
 502                 }
 503         } else if (version != 2) {
 504                 /* Unknown or unsupported version */
 505                 return FALSE;
 506         }
 507
 508         /* Was it sent between 2 even-numbered ports? */
 509         if ((pinfo->srcport % 2) || (pinfo->destport % 2)) {
 510                 return FALSE;
 511         }
 512
 513         /* Get the fields in the second octet */
 514         octet2 = tvb_get_guint8( tvb, offset + 1 );
 515         payload_type = RTP_PAYLOAD_TYPE( octet2 );
 516
 517         /* Check for a sensible payload type
 518            (recognised static and preferred dynamic ranges) */
 519         if ((payload_type <= PT_H263) ||
 520             (payload_type >= 96 && payload_type <= 127)) {
 521                 dissect_rtp( tvb, pinfo, tree );
 522                 return TRUE;
 523         }
 524         else {
 525                 return FALSE;
 526         }
 527 }
 528
 529 /*
 530  * Process the payload of the RTP packet, hand it to the subdissector
 531  */
 532 static void
 533 process_rtp_payload(tvbuff_t *newtvb, packet_info *pinfo, proto_tree *tree,
 534     proto_tree *rtp_tree,
 535     unsigned int payload_type)
 536 {
 537         struct _rtp_conversation_info *p_conv_data = NULL;
 538         gboolean found_match = FALSE;
 539         int payload_len;
 540         struct srtp_info *srtp_info;
 541         int offset=0;
 542
 543         payload_len = tvb_length_remaining(newtvb, offset);
 544
 545         /* first check if this is added as an SRTP stream - if so, don't try to dissector the payload data for now */
 546         p_conv_data = p_get_proto_data(pinfo->fd, proto_rtp);
 547         if (p_conv_data && p_conv_data->srtp_info) {
 548                 srtp_info = p_conv_data->srtp_info;
 549                 payload_len -= srtp_info->mki_len + srtp_info->auth_tag_len;
 550 #if 0
 551 #error Currently the srtp_info structure contains no cypher data, see packet-sdp.c adding dummy_srtp_info structure
 552                 if (p_conv_data->srtp_info->encryption_algorithm==SRTP_ENC_ALG_NULL) {
 553                         if (rtp_tree)
 554                                 proto_tree_add_text(rtp_tree, newtvb, offset, payload_len, "SRTP Payload with NULL encryption");
 555                 }
 556                 else
 557 #endif
 558                 {
 559                         if (rtp_tree)
 560                                 proto_tree_add_item(rtp_tree, hf_srtp_encrypted_payload, newtvb, offset, payload_len, FALSE);
 561                         found_match = TRUE;     /* use this flag to prevent dissection below */
 562                 }
 563                 offset += payload_len;
 564
 565                 if (srtp_info->mki_len) {
 566                         proto_tree_add_item(rtp_tree, hf_srtp_mki, newtvb, offset, srtp_info->mki_len, FALSE);
 567                         offset += srtp_info->mki_len;
 568                 }
 569
 570                 if (srtp_info->auth_tag_len) {
 571                         proto_tree_add_item(rtp_tree, hf_srtp_auth_tag, newtvb, offset, srtp_info->auth_tag_len, FALSE);
 572                         offset += srtp_info->auth_tag_len;
 573                 }
 574         }
 575
 576         /* if the payload type is dynamic (96 to 127), we check if the conv is set and we look for the pt definition */
 577         else if ( (payload_type >=96) && (payload_type <=127) ) {
 578                 if (p_conv_data && p_conv_data->rtp_dyn_payload) {
 579                         gchar *payload_type_str = NULL;
 580                         payload_type_str = g_hash_table_lookup(p_conv_data->rtp_dyn_payload, &payload_type);
 581                         if (payload_type_str){
 582                                 found_match = dissector_try_string(rtp_dyn_pt_dissector_table,
 583                                                                                                         payload_type_str, newtvb, pinfo, tree);
 584                                 /* If payload type string set from conversation and
 585                                  * no matching dissector found it's probably because no subdissector
 586                                  * exists. Don't call the dissectors based on payload number
 587                                  * as that'd probably be the wrong dissector in this case.
 588                                  * Just add it as data.
 589                                  */
 590                                 if(found_match==FALSE)
 591                                         proto_tree_add_item( rtp_tree, hf_rtp_data, newtvb, 0, -1, FALSE );
 592                                 return;
 593                         }
 594
 595                 }
 596         }
 597
 598         /* if we don't found, it is static OR could be set static from the preferences */
 599         if (!found_match && !dissector_try_port(rtp_pt_dissector_table, payload_type, newtvb, pinfo, tree))
 600                 proto_tree_add_item( rtp_tree, hf_rtp_data, newtvb, 0, -1, FALSE );
 601
 602 }
 603
 604 /* Rtp payload reassembly
 605  *
 606  * This handles the reassembly of PDUs for higher-level protocols.
 607  *
 608  * We're a bit limited on how we can cope with out-of-order packets, because
 609  * we don't have any idea of where the datagram boundaries are. So if we see
 610  * packets A, C, B (all of which comprise a single datagram), we cannot know
 611  * that C should be added to the same datagram as A, until we come to B (which
 612  * may or may not actually be present...).
 613  *
 614  * What we end up doing in this case is passing A+B to the subdissector as one
 615  * datagram, and make out that a new one starts on C.
 616  */
 617 static void
 618 dissect_rtp_data( tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree,
 619     proto_tree *rtp_tree, int offset, unsigned int data_len,
 620     unsigned int data_reported_len,
 621         unsigned int payload_type )
 622 {
 623         tvbuff_t *newtvb;
 624         struct _rtp_conversation_info *p_conv_data= NULL;
 625         gboolean must_desegment = FALSE;
 626         rtp_private_conv_info *finfo = NULL;
 627         rtp_multisegment_pdu *msp = NULL;
 628         guint32 seqno;
 629
 630         /* Retrieve RTPs idea of a converation */
 631         p_conv_data = p_get_proto_data(pinfo->fd, proto_rtp);
 632
 633         if(p_conv_data != NULL)
 634                 finfo = p_conv_data->rtp_conv_info;
 635
 636         if(finfo == NULL || !desegment_rtp) {
 637                 /* Hand the whole lot off to the subdissector */
 638                 newtvb=tvb_new_subset(tvb,offset,data_len,data_reported_len);
 639                 process_rtp_payload(newtvb, pinfo, tree, rtp_tree, payload_type);
 640                 return;
 641         }
 642
 643         seqno = p_conv_data->extended_seqno;
 644
 645         pinfo->can_desegment = 2;
 646         pinfo->desegment_offset = 0;
 647         pinfo->desegment_len = 0;
 648
 649 #ifdef DEBUG_FRAGMENTS
 650         g_debug("%d: RTP Part of convo %d(%p); seqno %d",
 651                 pinfo->fd->num,
 652                 p_conv_data->frame_number, p_conv_data,
 653                 seqno
 654                 );
 655 #endif
 656
 657         /* look for a pdu which we might be extending */
 658         msp = (rtp_multisegment_pdu *)se_tree_lookup32_le(finfo->multisegment_pdus,seqno-1);
 659
 660         if(msp && msp->startseq < seqno && msp->endseq >= seqno) {
 661                 guint32 fid = msp->startseq;
 662                 fragment_data *fd_head;
 663
 664 #ifdef DEBUG_FRAGMENTS
 665                 g_debug("\tContinues fragment %d", fid);
 666 #endif
 667
 668                 /* we always assume the datagram is complete; if this is the
 669                  * first pass, that's our best guess, and if it's not, what we
 670                  * say gets ignored anyway.
 671                  */
 672                 fd_head = fragment_add_seq(tvb, offset, pinfo, fid, fragment_table,
 673                                            seqno-msp->startseq, data_len, FALSE);
 674
 675                 newtvb = process_reassembled_data(tvb,offset, pinfo, "Reassembled RTP", fd_head,
 676                                                   &rtp_fragment_items, NULL, tree);
 677
 678 #ifdef DEBUG_FRAGMENTS
 679                 g_debug("\tFragment Coalesced; fd_head=%p, newtvb=%p (len %d)",fd_head, newtvb,
 680                         newtvb?tvb_reported_length(newtvb):0);
 681 #endif
 682
 683                 if(newtvb != NULL) {
 684                         /* Hand off to the subdissector */
 685                         process_rtp_payload(newtvb, pinfo, tree, rtp_tree, payload_type);
 686
 687                         /*
 688                          * Check to see if there were any complete fragments within the chunk
 689                          */
 690                         if( pinfo->desegment_len && pinfo->desegment_offset == 0 )
 691                         {
 692 #ifdef DEBUG_FRAGMENTS
 693                                 g_debug("\tNo complete pdus in payload" );
 694 #endif
 695                                 /* Mark the fragments and not complete yet */
 696                                 fragment_set_partial_reassembly(pinfo, fid, fragment_table);
 697
 698                                 /* we must need another segment */
 699                                 msp->endseq = MIN(msp->endseq,seqno) + 1;
 700                         }
 701                         else
 702                         {
 703                                 /*
 704                                  * Data was dissected so add the protocol tree to the display
 705                                  */
 706                                 proto_item *rtp_tree_item, *frag_tree_item;
 707                                 /* this nargery is to insert the fragment tree into the main tree
 708                                  * between the RTP protocol entry and the subdissector entry */
 709                                 show_fragment_tree(fd_head, &rtp_fragment_items, tree, pinfo, newtvb, &frag_tree_item);
 710                                 rtp_tree_item = proto_item_get_parent( proto_tree_get_parent( rtp_tree ));
 711                                 if( frag_tree_item && rtp_tree_item )
 712                                         proto_tree_move_item( tree, rtp_tree_item, frag_tree_item );
 713
 714
 715                                 if(pinfo->desegment_len)
 716                                 {
 717                                         /* the higher-level dissector has asked for some more data - ie,
 718                                            the end of this segment does not coincide with the end of a
 719                                            higher-level PDU. */
 720                                         must_desegment = TRUE;
 721                                 }
 722                         }
 723
 724                 }
 725
 726         }
 727         else
 728         {
 729                 /*
 730                  * The segment is not the continuation of a fragmented segment
 731                  * so process it as normal
 732                  */
 733 #ifdef DEBUG_FRAGMENTS
 734                 g_debug("\tRTP non-fragment payload");
 735 #endif
 736                 newtvb = tvb_new_subset( tvb, offset, data_len, data_reported_len );
 737
 738                 /* Hand off to the subdissector */
 739                 process_rtp_payload(newtvb, pinfo, tree, rtp_tree, payload_type);
 740
 741                 if(pinfo->desegment_len) {
 742                         /* the higher-level dissector has asked for some more data - ie,
 743                            the end of this segment does not coincide with the end of a
 744                            higher-level PDU. */
 745                         must_desegment = TRUE;
 746                 }
 747         }
 748
 749         /*
 750          * There were bytes left over that the higher protocol couldn't dissect so save them
 751          */
 752         if(must_desegment)
 753         {
 754                 guint32 deseg_offset = pinfo->desegment_offset;
 755                 guint32 frag_len = tvb_reported_length_remaining(newtvb, deseg_offset);
 756                 fragment_data *fd_head = NULL;
 757
 758 #ifdef DEBUG_FRAGMENTS
 759                 g_debug("\tRTP Must Desegment: tvb_len=%d ds_len=%d %d frag_len=%d ds_off=%d",
 760                         tvb_reported_length(newtvb),
 761                         pinfo->desegment_len,
 762                         pinfo->fd->flags.visited,
 763                         frag_len,
 764                         deseg_offset);
 765 #endif
 766                 /* allocate a new msp for this pdu */
 767                 msp = se_alloc(sizeof(rtp_multisegment_pdu));
 768                 msp->startseq = seqno;
 769                 msp->endseq = seqno+1;
 770                 se_tree_insert32(finfo->multisegment_pdus,seqno,msp);
 771
 772                 /*
 773                  * Add the fragment to the fragment table
 774                  */
 775                 fd_head = fragment_add_seq(newtvb,deseg_offset, pinfo, seqno, fragment_table, 0, frag_len,
 776                                            TRUE );
 777
 778                 if(fd_head != NULL)
 779                 {
 780                         if( fd_head->reassembled_in != 0 && !(fd_head->flags & FD_PARTIAL_REASSEMBLY) )
 781                         {
 782                                 proto_item *rtp_tree_item;
 783                                 rtp_tree_item = proto_tree_add_uint( tree, hf_rtp_reassembled_in,
 784                                                                      newtvb, deseg_offset, tvb_reported_length_remaining(newtvb,deseg_offset),
 785                                                                      fd_head->reassembled_in);
 786                                 PROTO_ITEM_SET_GENERATED(rtp_tree_item);
 787 #ifdef DEBUG_FRAGMENTS
 788                                 g_debug("\tReassembled in %d", fd_head->reassembled_in);
 789 #endif
 790                         }
 791                         else
 792                         {
 793 #ifdef DEBUG_FRAGMENTS
 794                                 g_debug("\tUnfinished fragment");
 795 #endif
 796                                 /* this fragment is never reassembled */
 797                                 proto_tree_add_text( tree, tvb, deseg_offset, -1,"RTP fragment, unfinished");
 798                         }
 799                 }
 800                 else
 801                 {
 802                         /*
 803                          * This fragment was the first fragment in a new entry in the
 804                          * frag_table; we don't yet know where it is reassembled
 805                          */
 806 #ifdef DEBUG_FRAGMENTS
 807                         g_debug("\tnew pdu");
 808 #endif
 809                 }
 810
 811                 if( pinfo->desegment_offset == 0 )
 812                 {
 813                         if (check_col(pinfo->cinfo, COL_PROTOCOL))
 814                         {
 815                                 col_set_str(pinfo->cinfo, COL_PROTOCOL, "RTP");
 816                         }
 817                         if (check_col(pinfo->cinfo, COL_INFO))
 818                         {
 819                                 col_set_str(pinfo->cinfo, COL_INFO, "[RTP segment of a reassembled PDU]");
 820                         }
 821                 }
 822         }
 823
 824
 825
 826         pinfo->can_desegment = 0;
 827         pinfo->desegment_offset = 0;
 828         pinfo->desegment_len = 0;
 829 }
 830
 831
 832
 833 static void
 834 dissect_rtp_rfc2198(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree )
 835 {
 836         int offset = 0;
 837         guint8 octet1;
 838         int cnt;
 839         gboolean hdr_follow = TRUE;
 840         proto_item *ti = NULL;
 841         proto_tree *rfc2198_tree = NULL;
 842         proto_tree *rfc2198_hdr_tree = NULL;
 843         rfc2198_hdr *hdr_last, *hdr_new;
 844         rfc2198_hdr *hdr_chain = NULL;
 845         struct _rtp_conversation_info *p_conv_data= NULL;
 846         gchar *payload_type_str;
 847
 848         /* Retrieve RTPs idea of a converation */
 849         p_conv_data = p_get_proto_data(pinfo->fd, proto_rtp);
 850
 851         /* Add try to RFC 2198 data */
 852         ti = proto_tree_add_text(tree, tvb, offset, -1, "RFC 2198: Redundant Audio Data");
 853         rfc2198_tree = proto_item_add_subtree(ti, ett_rtp_rfc2198);
 854
 855         hdr_last = NULL;
 856         cnt = 0;
 857         while (hdr_follow) {
 858                 cnt++;
 859                 payload_type_str = NULL;
 860
 861                 /* Allocate and fill in header */
 862                 hdr_new = ep_alloc(sizeof(rfc2198_hdr));
 863                 hdr_new->next = NULL;
 864                 octet1 = tvb_get_guint8(tvb, offset);
 865                 hdr_new->pt = RTP_PAYLOAD_TYPE(octet1);
 866                 hdr_follow = (octet1 & 0x80);
 867
 868                 /* if it is dynamic payload, let use the conv data to see if it is defined */
 869                 if ((hdr_new->pt > 95) && (hdr_new->pt < 128)) {
 870                         if (p_conv_data && p_conv_data->rtp_dyn_payload){
 871                                 payload_type_str = g_hash_table_lookup(p_conv_data->rtp_dyn_payload, &hdr_new->pt);
 872                         }
 873                 }
 874                 /* Add a subtree for this header and add items */
 875                 ti = proto_tree_add_text(rfc2198_tree, tvb, offset, (hdr_follow)?4:1, "Header %u", cnt);
 876                 rfc2198_hdr_tree = proto_item_add_subtree(ti, ett_rtp_rfc2198_hdr);
 877                 proto_tree_add_item(rfc2198_hdr_tree, hf_rtp_rfc2198_follow, tvb, offset, 1, FALSE );
 878                 proto_tree_add_uint_format(rfc2198_hdr_tree, hf_rtp_payload_type, tvb,
 879                     offset, 1, octet1, "Payload type: %s (%u)",
 880                         payload_type_str ? payload_type_str : val_to_str(hdr_new->pt, rtp_payload_type_vals, "Unknown"),
 881                         hdr_new->pt);
 882                 proto_item_append_text(ti, ": PT=%s", payload_type_str ? payload_type_str : val_to_str(hdr_new->pt, rtp_payload_type_vals, "Unknown (%u)"));
 883                 offset += 1;
 884
 885                 /* Timestamp offset and block length don't apply to last header */
 886                 if (hdr_follow) {
 887                         proto_tree_add_item(rfc2198_hdr_tree, hf_rtp_rfc2198_tm_off, tvb, offset, 2, FALSE );
 888                         proto_tree_add_item(rfc2198_hdr_tree, hf_rtp_rfc2198_bl_len, tvb, offset + 1, 2, FALSE );
 889                         hdr_new->len = tvb_get_ntohs(tvb, offset + 1) & 0x03FF;
 890                         proto_item_append_text(ti, ", len=%u", hdr_new->len);
 891                         offset += 3;
 892                 } else {
 893                         hdr_new->len = -1;
 894                         hdr_follow = FALSE;
 895                 }
 896
 897                 if (hdr_last) {
 898                         hdr_last->next = hdr_new;
 899                 } else {
 900                         hdr_chain = hdr_new;
 901                 }
 902                 hdr_last = hdr_new;
 903         }
 904
 905         /* Dissect each data block according to the header info */
 906         hdr_last = hdr_chain;
 907         while (hdr_last) {
 908                 hdr_last->offset = offset;
 909                 if (!hdr_last->next) {
 910                         hdr_last->len = tvb_reported_length_remaining(tvb, offset);
 911                 }
 912                 dissect_rtp_data(tvb, pinfo, tree, rfc2198_tree, hdr_last->offset, hdr_last->len, hdr_last->len, hdr_last->pt);
 913                 offset += hdr_last->len;
 914                 hdr_last = hdr_last->next;
 915         }
 916 }
 917
 918 static void
 919 dissect_rtp( tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree )
 920 {
 921         proto_item *ti            = NULL;
 922         proto_tree *rtp_tree      = NULL;
 923         proto_tree *rtp_csrc_tree = NULL;
 924         proto_tree *rtp_hext_tree = NULL;
 925         guint8      octet1, octet2;
 926         unsigned int version;
 927         gboolean    padding_set;
 928         gboolean    extension_set;
 929         unsigned int csrc_count;
 930         gboolean    marker_set;
 931         unsigned int payload_type;
 932         gchar *payload_type_str = NULL;
 933         gboolean    is_srtp = FALSE;
 934         unsigned int i            = 0;
 935         unsigned int hdr_extension= 0;
 936         unsigned int padding_count;
 937         gint        length, reported_length;
 938         int         data_len;
 939         unsigned int offset = 0;
 940         guint16     seq_num;
 941         guint32     timestamp;
 942         guint32     sync_src;
 943         guint32     csrc_item;
 944         struct _rtp_conversation_info *p_conv_data = NULL;
 945         struct srtp_info *srtp_info = NULL;
 946         unsigned int srtp_offset;
 947         unsigned int hdrext_offset = 0;
 948         tvbuff_t *newtvb = NULL;
 949
 950         /* Can tap up to 4 RTP packets within same packet */
 951         static struct _rtp_info rtp_info_arr[4];
 952         static int rtp_info_current=0;
 953         struct _rtp_info *rtp_info;
 954
 955         rtp_info_current++;
 956         if (rtp_info_current==4) {
 957                 rtp_info_current=0;
 958         }
 959         rtp_info = &rtp_info_arr[rtp_info_current];
 960
 961         /* Get the fields in the first octet */
 962         octet1 = tvb_get_guint8( tvb, offset );
 963         version = RTP_VERSION( octet1 );
 964
 965         if (version == 0) {
 966                 switch (global_rtp_version0_type) {
 967                 case RTP0_STUN:
 968                         call_dissector(stun_handle, tvb, pinfo, tree);
 969                         return;
 970
 971                 case RTP0_T38:
 972                         call_dissector(t38_handle, tvb, pinfo, tree);
 973                         return;
 974
 975                 case RTP0_INVALID:
 976                         if (!(tvb_memeql(tvb, 4, "ZRTP", 4)))
 977                         {
 978                                 call_dissector(zrtp_handle,tvb,pinfo,tree);
 979                                 return;
 980                         }
 981                 default:
 982                         ; /* Unknown or unsupported version (let it fall through) */
 983                 }
 984         }
 985
 986         /* fill in the rtp_info structure */
 987         rtp_info->info_version = version;
 988         if (version != 2) {
 989                 /*
 990                  * Unknown or unsupported version.
 991                  */
 992                 if ( check_col( pinfo->cinfo, COL_PROTOCOL ) )   {
 993                         col_set_str( pinfo->cinfo, COL_PROTOCOL, "RTP" );
 994                 }
 995
 996                 if ( check_col( pinfo->cinfo, COL_INFO) ) {
 997                         col_add_fstr( pinfo->cinfo, COL_INFO,
 998                             "Unknown RTP version %u", version);
 999                 }
1000
1001                 if ( tree ) {
1002                         ti = proto_tree_add_item( tree, proto_rtp, tvb, offset, -1, FALSE );
1003                         rtp_tree = proto_item_add_subtree( ti, ett_rtp );
1004
1005                         proto_tree_add_uint( rtp_tree, hf_rtp_version, tvb,
1006                             offset, 1, octet1);
1007                 }
1008                 return;
1009         }
1010
1011         padding_set = RTP_PADDING( octet1 );
1012         extension_set = RTP_EXTENSION( octet1 );
1013         csrc_count = RTP_CSRC_COUNT( octet1 );
1014
1015         /* Get the fields in the second octet */
1016         octet2 = tvb_get_guint8( tvb, offset + 1 );
1017         marker_set = RTP_MARKER( octet2 );
1018         payload_type = RTP_PAYLOAD_TYPE( octet2 );
1019
1020         /* Get the subsequent fields */
1021         seq_num = tvb_get_ntohs( tvb, offset + 2 );
1022         timestamp = tvb_get_ntohl( tvb, offset + 4 );
1023         sync_src = tvb_get_ntohl( tvb, offset + 8 );
1024
1025         /* fill in the rtp_info structure */
1026         rtp_info->info_padding_set = padding_set;
1027         rtp_info->info_padding_count = 0;
1028         rtp_info->info_marker_set = marker_set;
1029         rtp_info->info_payload_type = payload_type;
1030         rtp_info->info_seq_num = seq_num;
1031         rtp_info->info_timestamp = timestamp;
1032         rtp_info->info_sync_src = sync_src;
1033         rtp_info->info_is_srtp = FALSE;
1034         rtp_info->info_setup_frame_num = 0;
1035         rtp_info->info_payload_type_str = NULL;
1036
1037         /*
1038          * Do we have all the data?
1039          */
1040         length = tvb_length_remaining(tvb, offset);
1041         reported_length = tvb_reported_length_remaining(tvb, offset);
1042         if (reported_length >= 0 && length >= reported_length) {
1043                 /*
1044                  * Yes.
1045                  */
1046                 rtp_info->info_all_data_present = TRUE;
1047                 rtp_info->info_data_len = reported_length;
1048
1049                 /*
1050                  * Save the pointer to raw rtp data (header + payload incl.
1051                  * padding).
1052                  * That should be safe because the "epan_dissect_t"
1053                  * constructed for the packet has not yet been freed when
1054                  * the taps are called.
1055                  * (Destroying the "epan_dissect_t" will end up freeing
1056                  * all the tvbuffs and hence invalidating pointers to
1057                  * their data.)
1058                  * See "add_packet_to_packet_list()" for details.
1059                  */
1060                 rtp_info->info_data = tvb_get_ptr(tvb, 0, -1);
1061         } else {
1062                 /*
1063                  * No - packet was cut short at capture time.
1064                  */
1065                 rtp_info->info_all_data_present = FALSE;
1066                 rtp_info->info_data_len = 0;
1067                 rtp_info->info_data = NULL;
1068         }
1069
1070         /* Look for conv and add to the frame if found */
1071         get_conv_info(pinfo, rtp_info);
1072         p_conv_data = p_get_proto_data(pinfo->fd, proto_rtp);
1073
1074         if (p_conv_data && p_conv_data->srtp_info) is_srtp = TRUE;
1075         rtp_info->info_is_srtp = is_srtp;
1076
1077         if ( check_col( pinfo->cinfo, COL_PROTOCOL ) )   {
1078                 col_set_str( pinfo->cinfo, COL_PROTOCOL, (is_srtp) ? "SRTP" : "RTP" );
1079         }
1080
1081         /* check if this is added as an SRTP stream - if so, don't try to dissector the payload data for now */
1082         p_conv_data = p_get_proto_data(pinfo->fd, proto_rtp);
1083         if (p_conv_data && p_conv_data->srtp_info) {
1084                 srtp_info = p_conv_data->srtp_info;
1085                 if (rtp_info->info_all_data_present) {
1086                         srtp_offset = rtp_info->info_data_len - srtp_info->mki_len - srtp_info->auth_tag_len;
1087                 }
1088         }
1089
1090         /* if it is dynamic payload, let use the conv data to see if it is defined */
1091         if ( (payload_type>95) && (payload_type<128) ) {
1092                 if (p_conv_data && p_conv_data->rtp_dyn_payload){
1093                         payload_type_str = g_hash_table_lookup(p_conv_data->rtp_dyn_payload, &payload_type);
1094                         rtp_info->info_payload_type_str = payload_type_str;
1095                 }
1096         }
1097
1098         if ( check_col( pinfo->cinfo, COL_INFO) ) {
1099                 col_add_fstr( pinfo->cinfo, COL_INFO,
1100                     "PT=%s, SSRC=0x%X, Seq=%u, Time=%u%s",
1101                         payload_type_str ? payload_type_str : val_to_str( payload_type, rtp_payload_type_vals,"Unknown (%u)" ),
1102                     sync_src,
1103                     seq_num,
1104                     timestamp,
1105                     marker_set ? ", Mark " : " ");
1106         }
1107
1108
1109         if ( tree ) {
1110                 proto_tree *item;
1111                 /* Create RTP protocol tree */
1112                 ti = proto_tree_add_item(tree, proto_rtp, tvb, offset, -1, FALSE );
1113                 rtp_tree = proto_item_add_subtree(ti, ett_rtp );
1114
1115                 /* Conversation setup info */
1116                 if (global_rtp_show_setup_info)
1117                 {
1118                         show_setup_info(tvb, pinfo, rtp_tree);
1119                 }
1120
1121                 proto_tree_add_uint( rtp_tree, hf_rtp_version, tvb,
1122                     offset, 1, octet1 );
1123                 proto_tree_add_boolean( rtp_tree, hf_rtp_padding, tvb,
1124                     offset, 1, octet1 );
1125                 proto_tree_add_boolean( rtp_tree, hf_rtp_extension, tvb,
1126                     offset, 1, octet1 );
1127                 proto_tree_add_uint( rtp_tree, hf_rtp_csrc_count, tvb,
1128                     offset, 1, octet1 );
1129                 offset++;
1130
1131                 proto_tree_add_boolean( rtp_tree, hf_rtp_marker, tvb, offset,
1132                     1, octet2 );
1133
1134                 item = proto_tree_add_uint_format( rtp_tree, hf_rtp_payload_type, tvb,
1135                     offset, 1, octet2, "Payload type: %s (%u)",
1136                         payload_type_str ? payload_type_str : val_to_str( payload_type, rtp_payload_type_vals,"Unknown"),
1137                         payload_type);
1138
1139                 offset++;
1140
1141                 /* Sequence number 16 bits (2 octets) */
1142                 proto_tree_add_uint( rtp_tree, hf_rtp_seq_nr, tvb, offset, 2, seq_num );
1143                 if(p_conv_data != NULL) {
1144                         item = proto_tree_add_uint( rtp_tree, hf_rtp_ext_seq_nr, tvb, offset, 2, p_conv_data->extended_seqno );
1145                         PROTO_ITEM_SET_GENERATED(item);
1146                 }
1147                 offset += 2;
1148
1149                 /* Timestamp 32 bits (4 octets) */
1150                 proto_tree_add_uint( rtp_tree, hf_rtp_timestamp, tvb, offset, 4, timestamp );
1151                 offset += 4;
1152
1153                 /* Synchronization source identifier 32 bits (4 octets) */
1154                 proto_tree_add_uint( rtp_tree, hf_rtp_ssrc, tvb, offset, 4, sync_src );
1155                 offset += 4;
1156         } else {
1157                 offset += 12;
1158         }
1159         /* CSRC list*/
1160         if ( csrc_count > 0 ) {
1161                 if ( tree ) {
1162                         ti = proto_tree_add_item(rtp_tree, hf_rtp_csrc_items, tvb, offset,
1163                                                  csrc_count * 4, FALSE);
1164                         proto_item_append_text(ti, " (%u items)", csrc_count);
1165                         rtp_csrc_tree = proto_item_add_subtree( ti, ett_csrc_list );
1166                 }
1167                 for (i = 0; i < csrc_count; i++ ) {
1168                         csrc_item = tvb_get_ntohl( tvb, offset );
1169                         if ( tree ) proto_tree_add_uint_format( rtp_csrc_tree,
1170                             hf_rtp_csrc_item, tvb, offset, 4,
1171                             csrc_item,
1172                             "CSRC item %d: 0x%X",
1173                             i, csrc_item );
1174                         offset += 4;
1175                 }
1176         }
1177
1178         /* Optional RTP header extension */
1179         if ( extension_set ) {
1180                 /* Defined by profile field is 16 bits (2 octets) */
1181                 if ( tree ) proto_tree_add_uint( rtp_tree, hf_rtp_prof_define, tvb, offset, 2, tvb_get_ntohs( tvb, offset ) );
1182                 offset += 2;
1183
1184                 hdr_extension = tvb_get_ntohs( tvb, offset );
1185                 if ( tree ) proto_tree_add_uint( rtp_tree, hf_rtp_length, tvb, offset, 2, hdr_extension);
1186                 offset += 2;
1187                 if ( hdr_extension > 0 ) {
1188                         if ( tree ) {
1189                                 ti = proto_tree_add_item(rtp_tree, hf_rtp_hdr_exts, tvb, offset, hdr_extension * 4, FALSE);
1190                                 rtp_hext_tree = proto_item_add_subtree( ti, ett_hdr_ext );
1191                         }
1192
1193                         /* pass interpretation of header extension to a registered subdissector */
1194                         newtvb = tvb_new_subset(tvb, offset, hdr_extension * 4, hdr_extension * 4);
1195                         if ( !(rtp_info->info_payload_type_str && dissector_try_string(rtp_hdr_ext_dissector_table,
1196                                 rtp_info->info_payload_type_str, newtvb, pinfo, rtp_hext_tree)) ) {
1197                                 hdrext_offset = offset;
1198                                 for ( i = 0; i < hdr_extension; i++ ) {
1199                                         if ( tree ) proto_tree_add_uint( rtp_hext_tree, hf_rtp_hdr_ext, tvb, hdrext_offset, 4, tvb_get_ntohl( tvb, hdrext_offset ) );
1200                                         hdrext_offset += 4;
1201                                 }
1202                         }
1203                         offset += hdr_extension * 4;
1204                 }
1205         }
1206
1207         if ( padding_set ) {
1208                 /*
1209                  * This RTP frame has padding - find it.
1210                  *
1211                  * The padding count is found in the LAST octet of
1212                  * the packet; it contains the number of octets
1213                  * that can be ignored at the end of the packet.
1214                  */
1215                 if (tvb_length(tvb) < tvb_reported_length(tvb)) {
1216                         /*
1217                          * We don't *have* the last octet of the
1218                          * packet, so we can't get the padding
1219                          * count.
1220                          *
1221                          * Put an indication of that into the
1222                          * tree, and just put in a raw data
1223                          * item.
1224                          */
1225                         if ( tree ) proto_tree_add_text(rtp_tree, tvb, 0, 0,
1226                             "Frame has padding, but not all the frame data was captured");
1227                         call_dissector(data_handle,
1228                             tvb_new_subset(tvb, offset, -1, -1),
1229                             pinfo, rtp_tree);
1230                         return;
1231                 }
1232
1233                 padding_count = tvb_get_guint8( tvb,
1234                     tvb_reported_length( tvb ) - 1 );
1235                 data_len =
1236                     tvb_reported_length_remaining( tvb, offset ) - padding_count;
1237
1238                 rtp_info->info_payload_offset = offset;
1239                 rtp_info->info_payload_len = tvb_length_remaining(tvb, offset);
1240                 rtp_info->info_padding_count = padding_count;
1241
1242                 if (data_len > 0) {
1243                         /*
1244                          * There's data left over when you take out
1245                          * the padding; dissect it.
1246                          */
1247                         dissect_rtp_data( tvb, pinfo, tree, rtp_tree,
1248                             offset,
1249                             data_len,
1250                             data_len,
1251                             payload_type );
1252                         offset += data_len;
1253                 } else if (data_len < 0) {
1254                         /*
1255                          * The padding count is bigger than the
1256                          * amount of RTP payload in the packet!
1257                          * Clip the padding count.
1258                          *
1259                          * XXX - put an item in the tree to indicate
1260                          * that the padding count is bogus?
1261                          */
1262                         padding_count =
1263                             tvb_reported_length_remaining(tvb, offset);
1264                 }
1265                 if (padding_count > 1) {
1266                         /*
1267                          * There's more than one byte of padding;
1268                          * show all but the last byte as padding
1269                          * data.
1270                          */
1271                         if ( tree ) proto_tree_add_item( rtp_tree, hf_rtp_padding_data,
1272                             tvb, offset, padding_count - 1, FALSE );
1273                         offset += padding_count - 1;
1274                 }
1275                 /*
1276                  * Show the last byte in the PDU as the padding
1277                  * count.
1278                  */
1279                 if ( tree ) proto_tree_add_item( rtp_tree, hf_rtp_padding_count,
1280                     tvb, offset, 1, FALSE );
1281         }
1282         else {
1283                 /*
1284                  * No padding.
1285                  */
1286                 dissect_rtp_data( tvb, pinfo, tree, rtp_tree, offset,
1287                     tvb_length_remaining( tvb, offset ),
1288                     tvb_reported_length_remaining( tvb, offset ),
1289                     payload_type );
1290                 rtp_info->info_payload_offset = offset;
1291                 rtp_info->info_payload_len = tvb_length_remaining(tvb, offset);
1292         }
1293         if (!pinfo->in_error_pkt)
1294                 tap_queue_packet(rtp_tap, pinfo, rtp_info);
1295 }
1296
1297
1298 /* calculate the extended sequence number - top 16 bits of the previous sequence number,
1299  * plus our own; then correct for wrapping */
1300 static guint32 calculate_extended_seqno(guint32 previous_seqno, guint16 raw_seqno)
1301 {
1302         guint32 seqno = (previous_seqno & 0xffff0000) | raw_seqno;
1303         if(seqno + 0x8000 < previous_seqno) {
1304                 seqno += 0x10000;
1305         } else if(previous_seqno + 0x8000 < seqno) {
1306                 /* we got an out-of-order packet which happened to go backwards over the
1307                  * wrap boundary */
1308                 seqno -= 0x10000;
1309         }
1310         return seqno;
1311 }
1312
1313 /* Look for conversation info */
1314 static void get_conv_info(packet_info *pinfo, struct _rtp_info *rtp_info)
1315 {
1316         /* Conversation and current data */
1317         conversation_t *p_conv = NULL;
1318         struct _rtp_conversation_info *p_conv_data = NULL;
1319
1320         /* Use existing packet info if available */
1321         p_conv_data = p_get_proto_data(pinfo->fd, proto_rtp);
1322
1323         if (!p_conv_data)
1324         {
1325                 /* First time, get info from conversation */
1326                 p_conv = find_conversation(pinfo->fd->num, &pinfo->net_dst, &pinfo->net_src,
1327                                            pinfo->ptype,
1328                                            pinfo->destport, pinfo->srcport, NO_ADDR_B);
1329                 if (p_conv)
1330                 {
1331                         /* Create space for packet info */
1332                         struct _rtp_conversation_info *p_conv_packet_data;
1333                         p_conv_data = conversation_get_proto_data(p_conv, proto_rtp);
1334
1335                         if (p_conv_data) {
1336                                 guint32 seqno;
1337
1338                                 /* Save this conversation info into packet info */
1339                                 p_conv_packet_data = se_alloc(sizeof(struct _rtp_conversation_info));
1340                                 g_snprintf(p_conv_packet_data->method, MAX_RTP_SETUP_METHOD_SIZE+1, "%s", p_conv_data->method);
1341                                 p_conv_packet_data->method[MAX_RTP_SETUP_METHOD_SIZE]='\0';
1342                                 p_conv_packet_data->frame_number = p_conv_data->frame_number;
1343                                 p_conv_packet_data->rtp_dyn_payload = p_conv_data->rtp_dyn_payload;
1344                                 p_conv_packet_data->rtp_conv_info = p_conv_data->rtp_conv_info;
1345                                 p_conv_packet_data->srtp_info = p_conv_data->srtp_info;
1346                                 p_add_proto_data(pinfo->fd, proto_rtp, p_conv_packet_data);
1347
1348                                 /* calculate extended sequence number */
1349                                 seqno = calculate_extended_seqno(p_conv_data->extended_seqno,
1350                                                                  rtp_info->info_seq_num);
1351
1352                                 p_conv_packet_data->extended_seqno = seqno;
1353                                 p_conv_data->extended_seqno = seqno;
1354                         }
1355                 }
1356         }
1357         if (p_conv_data) rtp_info->info_setup_frame_num = p_conv_data->frame_number;
1358 }
1359
1360
1361 /* Display setup info */
1362 static void show_setup_info(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
1363 {
1364         /* Conversation and current data */
1365         struct _rtp_conversation_info *p_conv_data = NULL;
1366         proto_tree *rtp_setup_tree;
1367         proto_item *ti;
1368
1369         /* Use existing packet info if available */
1370         p_conv_data = p_get_proto_data(pinfo->fd, proto_rtp);
1371
1372         if (!p_conv_data) return;
1373
1374         /* Create setup info subtree with summary info. */
1375         ti =  proto_tree_add_string_format(tree, hf_rtp_setup, tvb, 0, 0,
1376                                                                "",
1377                                                                "Stream setup by %s (frame %u)",
1378                                                                p_conv_data->method,
1379                                                                p_conv_data->frame_number);
1380                 PROTO_ITEM_SET_GENERATED(ti);
1381                 rtp_setup_tree = proto_item_add_subtree(ti, ett_rtp_setup);
1382                 if (rtp_setup_tree)
1383                 {
1384                         /* Add details into subtree */
1385                         proto_item* item = proto_tree_add_uint(rtp_setup_tree, hf_rtp_setup_frame,
1386                                                                tvb, 0, 0, p_conv_data->frame_number);
1387                         PROTO_ITEM_SET_GENERATED(item);
1388                         item = proto_tree_add_string(rtp_setup_tree, hf_rtp_setup_method,
1389                                                      tvb, 0, 0, p_conv_data->method);
1390                         PROTO_ITEM_SET_GENERATED(item);
1391                 }
1392 }
1393
1394 /* Dissect PacketCable CCC header */
1395
1396 static void
1397 dissect_pkt_ccc(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
1398 {
1399         proto_item *ti            = NULL;
1400         proto_tree *pkt_ccc_tree      = NULL;
1401         const guint8 *ptime = tvb_get_ptr(tvb, 4, 8);
1402
1403         if ( tree ) {
1404                 ti = proto_tree_add_item(tree, proto_pkt_ccc, tvb, 0, 12, FALSE);
1405                 pkt_ccc_tree = proto_item_add_subtree(ti, ett_pkt_ccc);
1406
1407                 proto_tree_add_item(pkt_ccc_tree, hf_pkt_ccc_id, tvb, 0, 4, FALSE);
1408                 proto_tree_add_bytes_format(pkt_ccc_tree, hf_pkt_ccc_ts, tvb,
1409                     4, 8, ptime, "NTP timestamp: %s", ntp_fmt_ts(ptime));
1410         }
1411
1412         dissect_rtp(tvb, pinfo, tree);
1413 }
1414
1415
1416 /* Register PacketCable CCC */
1417
1418 void
1419 proto_register_pkt_ccc(void)
1420 {
1421         static hf_register_info hf[] =
1422         {
1423                 {
1424                         &hf_pkt_ccc_id,
1425                         {
1426                                 "PacketCable CCC Identifier",
1427                                 "pkt_ccc.ccc_id",
1428                                 FT_UINT32,
1429                                 BASE_DEC,
1430                                 NULL,
1431                                 0x0,
1432                                 "CCC_ID", HFILL
1433                         }
1434                 },
1435                 {
1436                         &hf_pkt_ccc_ts,
1437                         {
1438                                 "PacketCable CCC Timestamp",
1439                                 "pkt_ccc.ts",
1440                                 FT_BYTES,
1441                                 BASE_NONE,
1442                                 NULL,
1443                                 0x0,
1444                                 "Timestamp", HFILL
1445                         }
1446                 },
1447
1448         };
1449
1450         static gint *ett[] =
1451         {
1452                 &ett_pkt_ccc,
1453         };
1454
1455         module_t *pkt_ccc_module;
1456
1457         proto_pkt_ccc = proto_register_protocol("PacketCable Call Content Connection",
1458             "PKT CCC", "pkt_ccc");
1459         proto_register_field_array(proto_pkt_ccc, hf, array_length(hf));
1460         proto_register_subtree_array(ett, array_length(ett));
1461
1462         register_dissector("pkt_ccc", dissect_pkt_ccc, proto_pkt_ccc);
1463
1464         pkt_ccc_module = prefs_register_protocol(proto_pkt_ccc, proto_reg_handoff_pkt_ccc);
1465
1466         prefs_register_uint_preference(pkt_ccc_module, "udp_port",
1467                                        "UDP port",
1468                                        "Decode packets on this UDP port as PacketCable CCC",
1469                                        10, &global_pkt_ccc_udp_port);
1470 }
1471
1472 void
1473 proto_reg_handoff_pkt_ccc(void)
1474 {
1475         /*
1476          * Register this dissector as one that can be selected by a
1477          * UDP port number.
1478          */
1479         static gboolean initialized = FALSE;
1480         static dissector_handle_t pkt_ccc_handle;
1481         static guint saved_pkt_ccc_udp_port;
1482
1483         if (!initialized) {
1484                 pkt_ccc_handle = find_dissector("pkt_ccc");
1485                 dissector_add_handle("udp.port", pkt_ccc_handle);  /* for 'decode-as' */
1486                 initialized = TRUE;
1487         } else {
1488                 if (saved_pkt_ccc_udp_port != 0) {
1489                         dissector_delete("udp.port", saved_pkt_ccc_udp_port, pkt_ccc_handle);
1490                 }
1491         }
1492
1493         if (global_pkt_ccc_udp_port != 0) {
1494                 dissector_add("udp.port", global_pkt_ccc_udp_port, pkt_ccc_handle);
1495         }
1496         saved_pkt_ccc_udp_port = global_pkt_ccc_udp_port;
1497 }
1498
1499 /* Register RTP */
1500
1501 void
1502 proto_register_rtp(void)
1503 {
1504         static hf_register_info hf[] =
1505         {
1506                 {
1507                         &hf_rtp_version,
1508                         {
1509                                 "Version",
1510                                 "rtp.version",
1511                                 FT_UINT8,
1512                                 BASE_DEC,
1513                                 VALS(rtp_version_vals),
1514                                 0xC0,
1515                                 "", HFILL
1516                         }
1517                 },
1518                 {
1519                         &hf_rtp_padding,
1520                         {
1521                                 "Padding",
1522                                 "rtp.padding",
1523                                 FT_BOOLEAN,
1524                                 8,
1525                                 NULL,
1526                                 0x20,
1527                                 "", HFILL
1528                         }
1529                 },
1530                 {
1531                         &hf_rtp_extension,
1532                         {
1533                                 "Extension",
1534                                 "rtp.ext",
1535                                 FT_BOOLEAN,
1536                                 8,
1537                                 NULL,
1538                                 0x10,
1539                                 "", HFILL
1540                         }
1541                 },
1542                 {
1543                         &hf_rtp_csrc_count,
1544                         {
1545                                 "Contributing source identifiers count",
1546                                 "rtp.cc",
1547                                 FT_UINT8,
1548                                 BASE_DEC,
1549                                 NULL,
1550                                 0x0F,
1551                                 "", HFILL
1552                         }
1553                 },
1554                 {
1555                         &hf_rtp_marker,
1556                         {
1557                                 "Marker",
1558                                 "rtp.marker",
1559                                 FT_BOOLEAN,
1560                                 8,
1561                                 NULL,
1562                                 0x80,
1563                                 "", HFILL
1564                         }
1565                 },
1566                 {
1567                         &hf_rtp_payload_type,
1568                         {
1569                                 "Payload type",
1570                                 "rtp.p_type",
1571                                 FT_UINT8,
1572                                 BASE_DEC,
1573                                 NULL,
1574                                 0x7F,
1575                                 "", HFILL
1576                         }
1577                 },
1578                 {
1579                         &hf_rtp_seq_nr,
1580                         {
1581                                 "Sequence number",
1582                                 "rtp.seq",
1583                                 FT_UINT16,
1584                                 BASE_DEC,
1585                                 NULL,
1586                                 0x0,
1587                                 "", HFILL
1588                         }
1589                 },
1590                 {
1591                         &hf_rtp_ext_seq_nr,
1592                         {
1593                                 "Extended sequence number",
1594                                 "rtp.extseq",
1595                                 FT_UINT32,
1596                                 BASE_DEC,
1597                                 NULL,
1598                                 0x0,
1599                                 "", HFILL
1600                         }
1601                 },
1602                 {
1603                         &hf_rtp_timestamp,
1604                         {
1605                                 "Timestamp",
1606                                 "rtp.timestamp",
1607                                 FT_UINT32,
1608                                 BASE_DEC,
1609                                 NULL,
1610                                 0x0,
1611                                 "", HFILL
1612                         }
1613                 },
1614                 {
1615                         &hf_rtp_ssrc,
1616                         {
1617                                 "Synchronization Source identifier",
1618                                 "rtp.ssrc",
1619                                 FT_UINT32,
1620                                 BASE_HEX_DEC,
1621                                 NULL,
1622                                 0x0,
1623                                 "", HFILL
1624                         }
1625                 },
1626                 {
1627                         &hf_rtp_prof_define,
1628                         {
1629                                 "Defined by profile",
1630                                 "rtp.ext.profile",
1631                                 FT_UINT16,
1632                                 BASE_DEC,
1633                                 NULL,
1634                                 0x0,
1635                                 "", HFILL
1636                         }
1637                 },
1638                 {
1639                         &hf_rtp_length,
1640                         {
1641                                 "Extension length",
1642                                 "rtp.ext.len",
1643                                 FT_UINT16,
1644                                 BASE_DEC,
1645                                 NULL,
1646                                 0x0,
1647                                 "", HFILL
1648                         }
1649                 },
1650                 {
1651                         &hf_rtp_csrc_items,
1652                         {
1653                                 "Contributing Source identifiers",
1654                                 "rtp.csrc.items",
1655                                 FT_NONE,
1656                                 BASE_NONE,
1657                                 NULL,
1658                                 0x0,
1659                                 "", HFILL
1660                         }
1661                 },
1662                 {
1663                         &hf_rtp_csrc_item,
1664                         {
1665                                 "CSRC item",
1666                                 "rtp.csrc.item",
1667                                 FT_UINT32,
1668                                 BASE_HEX_DEC,
1669                                 NULL,
1670                                 0x0,
1671                                 "", HFILL
1672                         }
1673                 },
1674                 {
1675                         &hf_rtp_hdr_exts,
1676                         {
1677                                 "Header extensions",
1678                                 "rtp.hdr_exts",
1679                                 FT_NONE,
1680                                 BASE_NONE,
1681                                 NULL,
1682                                 0x0,
1683                                 "", HFILL
1684                         }
1685                 },
1686                 {
1687                         &hf_rtp_hdr_ext,
1688                         {
1689                                 "Header extension",
1690                                 "rtp.hdr_ext",
1691                                 FT_UINT32,
1692                                 BASE_DEC,
1693                                 NULL,
1694                                 0x0,
1695                                 "", HFILL
1696                         }
1697                 },
1698                 {
1699                         &hf_rtp_data,
1700                         {
1701                                 "Payload",
1702                                 "rtp.payload",
1703                                 FT_BYTES,
1704                                 BASE_HEX,
1705                                 NULL,
1706                                 0x0,
1707                                 "", HFILL
1708                         }
1709                 },
1710                 {
1711                         &hf_rtp_padding_data,
1712                         {
1713                                 "Padding data",
1714                                 "rtp.padding.data",
1715                                 FT_BYTES,
1716                                 BASE_HEX,
1717                                 NULL,
1718                                 0x0,
1719                                 "", HFILL
1720                         }
1721                 },
1722                 {
1723                         &hf_rtp_padding_count,
1724                         {
1725                                 "Padding count",
1726                                 "rtp.padding.count",
1727                                 FT_UINT8,
1728                                 BASE_DEC,
1729                                 NULL,
1730                                 0x0,
1731                                 "", HFILL
1732                         }
1733                 },
1734                 {
1735                         &hf_rtp_setup,
1736                         {
1737                                 "Stream setup",
1738                                 "rtp.setup",
1739                                 FT_STRING,
1740                                 BASE_NONE,
1741                                 NULL,
1742                                 0x0,
1743                                 "Stream setup, method and frame number", HFILL
1744                         }
1745                 },
1746                 {
1747                         &hf_rtp_setup_frame,
1748                         {
1749                                 "Setup frame",
1750                                 "rtp.setup-frame",
1751                                 FT_FRAMENUM,
1752                                 BASE_NONE,
1753                                 NULL,
1754                                 0x0,
1755                                 "Frame that set up this stream", HFILL
1756                         }
1757                 },
1758                 {
1759                         &hf_rtp_setup_method,
1760                         {
1761                                 "Setup Method",
1762                                 "rtp.setup-method",
1763                                 FT_STRING,
1764                                 BASE_NONE,
1765                                 NULL,
1766                                 0x0,
1767                                 "Method used to set up this stream", HFILL
1768                         }
1769                 },
1770                 {
1771                         &hf_rtp_rfc2198_follow,
1772                         {
1773                                 "Follow",
1774                                 "rtp.follow",
1775                                 FT_BOOLEAN,
1776                                 8,
1777                                 TFS(&flags_set_truth),
1778                                 0x80,
1779                                 "Next header follows", HFILL
1780                         }
1781                 },
1782                 {
1783                         &hf_rtp_rfc2198_tm_off,
1784                         {
1785                                 "Timestamp offset",
1786                                 "rtp.timestamp-offset",
1787                                 FT_UINT16,
1788                                 BASE_DEC,
1789                                 NULL,
1790                                 0xFFFC,
1791                                 "Timestamp Offset", HFILL
1792                         }
1793                 },
1794                 {
1795                         &hf_rtp_rfc2198_bl_len,
1796                         {
1797                                 "Block length",
1798                                 "rtp.block-length",
1799                                 FT_UINT16,
1800                                 BASE_DEC,
1801                                 NULL,
1802                                 0x03FF,
1803                                 "Block Length", HFILL
1804                         }
1805                 },
1806
1807                 /* reassembly stuff */
1808                 {&hf_rtp_fragments,
1809                  {"RTP Fragments", "rtp.fragments", FT_NONE, BASE_NONE, NULL, 0x0,
1810                   "RTP Fragments", HFILL }
1811                 },
1812
1813                 {&hf_rtp_fragment,
1814                  {"RTP Fragment data", "rtp.fragment", FT_FRAMENUM, BASE_NONE, NULL, 0x0,
1815                   "RTP Fragment data", HFILL }
1816                 },
1817
1818                 {&hf_rtp_fragment_overlap,
1819                  {"Fragment overlap", "rtp.fragment.overlap", FT_BOOLEAN, BASE_NONE,
1820                   NULL, 0x0, "Fragment overlaps with other fragments", HFILL }
1821                 },
1822
1823                 {&hf_rtp_fragment_overlap_conflict,
1824                  {"Conflicting data in fragment overlap", "rtp.fragment.overlap.conflict",
1825                   FT_BOOLEAN, BASE_NONE, NULL, 0x0,
1826                   "Overlapping fragments contained conflicting data", HFILL }
1827                 },
1828
1829                 {&hf_rtp_fragment_multiple_tails,
1830                  {"Multiple tail fragments found", "rtp.fragment.multipletails",
1831                   FT_BOOLEAN, BASE_NONE, NULL, 0x0,
1832                   "Several tails were found when defragmenting the packet", HFILL }
1833                 },
1834
1835                 {&hf_rtp_fragment_too_long_fragment,
1836                  {"Fragment too long", "rtp.fragment.toolongfragment",
1837                   FT_BOOLEAN, BASE_NONE, NULL, 0x0,
1838                   "Fragment contained data past end of packet", HFILL }
1839                 },
1840
1841                 {&hf_rtp_fragment_error,
1842                  {"Defragmentation error", "rtp.fragment.error",
1843                   FT_FRAMENUM, BASE_NONE, NULL, 0x0,
1844                   "Defragmentation error due to illegal fragments", HFILL }
1845                 },
1846
1847                 {&hf_rtp_reassembled_in,
1848                  {"RTP fragment, reassembled in frame", "rtp.reassembled_in",
1849                   FT_FRAMENUM, BASE_NONE, NULL, 0x0,
1850                   "This RTP packet is reassembled in this frame", HFILL }
1851                 },
1852                 {&hf_srtp_encrypted_payload,
1853                  {"SRTP Encrypted Payload", "srtp.enc_payload",
1854                   FT_BYTES, BASE_NONE, NULL, 0x0,
1855                   "SRTP Encrypted Payload", HFILL }
1856                 },
1857                 {&hf_srtp_mki,
1858                  {"SRTP MKI", "srtp.mki",
1859                   FT_BYTES, BASE_NONE, NULL, 0x0,
1860                   "SRTP Master Key Index", HFILL }
1861                 },
1862                 {&hf_srtp_auth_tag,
1863                  {"SRTP Auth Tag", "srtp.auth_tag",
1864                   FT_BYTES, BASE_NONE, NULL, 0x0,
1865                   "SRTP Authentication Tag", HFILL }
1866                 }
1867
1868         };
1869
1870         static gint *ett[] =
1871         {
1872                 &ett_rtp,
1873                 &ett_csrc_list,
1874                 &ett_hdr_ext,
1875                 &ett_rtp_setup,
1876                 &ett_rtp_rfc2198,
1877                 &ett_rtp_rfc2198_hdr,
1878                 &ett_rtp_fragment,
1879                 &ett_rtp_fragments
1880         };
1881
1882         module_t *rtp_module;
1883
1884
1885         proto_rtp = proto_register_protocol("Real-Time Transport Protocol",
1886             "RTP", "rtp");
1887         proto_register_field_array(proto_rtp, hf, array_length(hf));
1888         proto_register_subtree_array(ett, array_length(ett));
1889
1890         register_dissector("rtp", dissect_rtp, proto_rtp);
1891         register_dissector("rtp.rfc2198", dissect_rtp_rfc2198, proto_rtp);
1892
1893         rtp_tap = register_tap("rtp");
1894
1895         rtp_pt_dissector_table = register_dissector_table("rtp.pt",
1896                                                           "RTP payload type", FT_UINT8, BASE_DEC);
1897         rtp_dyn_pt_dissector_table = register_dissector_table("rtp_dyn_payload_type",
1898                                                                                                     "Dynamic RTP payload type", FT_STRING, BASE_NONE);
1899
1900
1901         rtp_hdr_ext_dissector_table = register_dissector_table("rtp_hdr_ext",
1902                                                                                                         "RTP header extension", FT_STRING, BASE_NONE);
1903
1904         rtp_module = prefs_register_protocol(proto_rtp, proto_reg_handoff_rtp);
1905
1906         prefs_register_bool_preference(rtp_module, "show_setup_info",
1907                                        "Show stream setup information",
1908                                        "Where available, show which protocol and frame caused "
1909                                        "this RTP stream to be created",
1910                                        &global_rtp_show_setup_info);
1911
1912         prefs_register_bool_preference(rtp_module, "heuristic_rtp",
1913                                        "Try to decode RTP outside of conversations",
1914                                        "If call control SIP/H323/RTSP/.. messages are missing in the trace, "
1915                                        "RTP isn't decoded without this",
1916                                        &global_rtp_heur);
1917
1918         prefs_register_bool_preference(rtp_module, "desegment_rtp_streams",
1919                                        "Allow subdissector to reassemble RTP streams",
1920                                        "Whether subdissector can request RTP streams to be reassembled",
1921                                        &desegment_rtp);
1922
1923         prefs_register_enum_preference(rtp_module, "version0_type",
1924                                        "Treat RTP version 0 packets as",
1925                                        "If an RTP version 0 packet is encountered, it can be treated as an invalid or ZRTP packet, a STUN packet, or a T.38 packet",
1926                                        &global_rtp_version0_type,
1927                                        rtp_version0_types, FALSE);
1928         prefs_register_uint_preference(rtp_module,
1929                                        "rfc2198_payload_type", "Payload Type for RFC2198",
1930                                        "Payload Type for RFC2198 Redundant Audio Data",
1931                                        10,
1932                                        &rtp_rfc2198_pt);
1933
1934         register_init_routine(rtp_fragment_init);
1935 }
1936
1937 void
1938 proto_reg_handoff_rtp(void)
1939 {
1940         static gboolean rtp_prefs_initialized = FALSE;
1941         static dissector_handle_t rtp_rfc2198_handle;
1942         static guint rtp_saved_rfc2198_pt;
1943
1944         if (!rtp_prefs_initialized) {
1945                 rtp_handle = find_dissector("rtp");
1946                 rtp_rfc2198_handle = find_dissector("rtp.rfc2198");
1947
1948                 dissector_add_handle("udp.port", rtp_handle);  /* for 'decode-as' */
1949                 dissector_add_string("rtp_dyn_payload_type", "red", rtp_rfc2198_handle);
1950                 heur_dissector_add( "udp", dissect_rtp_heur, proto_rtp);
1951                 heur_dissector_add("stun2", dissect_rtp_heur, proto_rtp);
1952
1953                 data_handle = find_dissector("data");
1954                 stun_handle = find_dissector("stun");
1955                 stun_heur_handle = find_dissector("stun-heur");
1956                 t38_handle = find_dissector("t38");
1957                 zrtp_handle = find_dissector("zrtp");
1958
1959                 rtp_prefs_initialized = TRUE;
1960         } else {
1961                 dissector_delete("rtp.pt", rtp_saved_rfc2198_pt, rtp_rfc2198_handle);
1962         }
1963         dissector_add("rtp.pt", rtp_rfc2198_pt, rtp_rfc2198_handle);
1964         rtp_saved_rfc2198_pt = rtp_rfc2198_pt;
1965 }
1966
1967 /*
1968  * Local Variables:
1969  * c-basic-offset: 8
1970  * indent-tabs-mode: t
1971  * tab-width: 8
1972  * End:
1973  */