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 classicstun_handle;
 138 static dissector_handle_t classicstun_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_CLASSICSTUN    1
 208 #define RTP0_T38     2
 209
 210 static enum_val_t rtp_version0_types[] = {
 211         { "invalid", "Invalid or ZRTP packets", RTP0_INVALID },
 212         { "classicstun", "CLASSIC-STUN packets", RTP0_CLASSICSTUN },
 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
 308         /* Alex Lindberg - Added to support addtional RTP payload types
 309         See epan/rtp_pt.h */
 310         { PT_UNDF_96,   "DynamicRTP-Type-96" },
 311         { PT_UNDF_97,   "DynamicRTP-Type-97" },
 312         { PT_UNDF_98,   "DynamicRTP-Type-98" },
 313         { PT_UNDF_99,   "DynamicRTP-Type-99" },
 314         { PT_UNDF_100,  "DynamicRTP-Type-100" },
 315         { PT_UNDF_101,  "DynamicRTP-Type-101" },
 316         { PT_UNDF_102,  "DynamicRTP-Type-102" },
 317         { PT_UNDF_103,  "DynamicRTP-Type-103" },
 318         { PT_UNDF_104,  "DynamicRTP-Type-104" },
 319         { PT_UNDF_105,  "DynamicRTP-Type-105" },
 320         { PT_UNDF_106,  "DynamicRTP-Type-106" },
 321         { PT_UNDF_107,  "DynamicRTP-Type-107" },
 322         { PT_UNDF_108,  "DynamicRTP-Type-108" },
 323         { PT_UNDF_109,  "DynamicRTP-Type-109" },
 324         { PT_UNDF_110,  "DynamicRTP-Type-110" },
 325         { PT_UNDF_111,  "DynamicRTP-Type-111" },
 326         { PT_UNDF_112,  "DynamicRTP-Type-112" },
 327         { PT_UNDF_113,  "DynamicRTP-Type-113" },
 328         { PT_UNDF_114,  "DynamicRTP-Type-114" },
 329         { PT_UNDF_115,  "DynamicRTP-Type-115" },
 330         { PT_UNDF_116,  "DynamicRTP-Type-116" },
 331         { PT_UNDF_117,  "DynamicRTP-Type-117" },
 332         { PT_UNDF_118,  "DynamicRTP-Type-118" },
 333         { PT_UNDF_119,  "DynamicRTP-Type-119" },
 334         { PT_UNDF_120,  "DynamicRTP-Type-120" },
 335         { PT_UNDF_121,  "DynamicRTP-Type-121" },
 336         { PT_UNDF_122,  "DynamicRTP-Type-122" },
 337         { PT_UNDF_123,  "DynamicRTP-Type-123" },
 338         { PT_UNDF_124,  "DynamicRTP-Type-124" },
 339         { PT_UNDF_125,  "DynamicRTP-Type-125" },
 340         { PT_UNDF_126,  "DynamicRTP-Type-126" },
 341         { PT_UNDF_127,  "DynamicRTP-Type-127" },
 342
 343         { 0,            NULL },
 344 };
 345
 346 const value_string rtp_payload_type_short_vals[] =
 347 {
 348         { PT_PCMU,      "g711U" },
 349         { PT_1016,      "fs-1016" },
 350         { PT_G721,      "g721" },
 351         { PT_GSM,       "GSM" },
 352         { PT_G723,      "g723" },
 353         { PT_DVI4_8000, "DVI4 8k" },
 354         { PT_DVI4_16000, "DVI4 16k" },
 355         { PT_LPC,       "Exp. from Xerox PARC" },
 356         { PT_PCMA,      "g711A" },
 357         { PT_G722,      "g722" },
 358         { PT_L16_STEREO, "16-bit audio, stereo" },
 359         { PT_L16_MONO,  "16-bit audio, monaural" },
 360         { PT_QCELP,     "Qualcomm" },
 361         { PT_CN,        "CN" },
 362         { PT_MPA,       "MPEG-I/II Audio"},
 363         { PT_G728,      "g728" },
 364         { PT_DVI4_11025, "DVI4 11k" },
 365         { PT_DVI4_22050, "DVI4 22k" },
 366         { PT_G729,      "g729" },
 367         { PT_CN_OLD,    "CN(old)" },
 368         { PT_CELB,      "CellB" },
 369         { PT_JPEG,      "JPEG" },
 370         { PT_NV,        "NV" },
 371         { PT_H261,      "h261" },
 372         { PT_MPV,       "MPEG-I/II Video"},
 373         { PT_MP2T,      "MPEG-II streams"},
 374         { PT_H263,      "h263" },
 375
 376         /* Alex Lindberg - Short RTP types */
 377         { PT_UNDF_96,   "RTPType-96" },
 378         { PT_UNDF_97,   "RTPType-97" },
 379         { PT_UNDF_98,   "RTPType-98" },
 380         { PT_UNDF_99,   "RTPType-99" },
 381         { PT_UNDF_100,  "RTPType-100" },
 382         { PT_UNDF_101,  "RTPType-101" },
 383         { PT_UNDF_102,  "RTPType-102" },
 384         { PT_UNDF_103,  "RTPType-103" },
 385         { PT_UNDF_104,  "RTPType-104" },
 386         { PT_UNDF_105,  "RTPType-105" },
 387         { PT_UNDF_106,  "RTPType-106" },
 388         { PT_UNDF_107,  "RTPType-107" },
 389         { PT_UNDF_108,  "RTPType-108" },
 390         { PT_UNDF_109,  "RTPType-109" },
 391         { PT_UNDF_110,  "RTPType-110" },
 392         { PT_UNDF_111,  "RTPType-111" },
 393         { PT_UNDF_112,  "RTPType-112" },
 394         { PT_UNDF_113,  "RTPType-113" },
 395         { PT_UNDF_114,  "RTPType-114" },
 396         { PT_UNDF_115,  "RTPType-115" },
 397         { PT_UNDF_116,  "RTPType-116" },
 398         { PT_UNDF_117,  "RTPType-117" },
 399         { PT_UNDF_118,  "RTPType-118" },
 400         { PT_UNDF_119,  "RTPType-119" },
 401         { PT_UNDF_120,  "RTPType-120" },
 402         { PT_UNDF_121,  "RTPType-121" },
 403         { PT_UNDF_122,  "RTPType-122" },
 404         { PT_UNDF_123,  "RTPType-123" },
 405         { PT_UNDF_124,  "RTPType-124" },
 406         { PT_UNDF_125,  "RTPType-125" },
 407         { PT_UNDF_126,  "RTPType-126" },
 408         { PT_UNDF_127,  "RTPType-127" },
 409
 410         { 0,            NULL },
 411 };
 412 #if 0
 413 static const value_string srtp_encryption_alg_vals[] =
 414 {
 415         { SRTP_ENC_ALG_NULL,    "Null Encryption" },
 416         { SRTP_ENC_ALG_AES_CM, "AES-128 Counter Mode" },
 417         { SRTP_ENC_ALG_AES_F8,  "AES-128 F8 Mode" },
 418         { 0, NULL },
 419 };
 420
 421 static const value_string srtp_auth_alg_vals[] =
 422 {
 423         { SRTP_AUTH_ALG_NONE,           "No Authentication" },
 424         { SRTP_AUTH_ALG_HMAC_SHA1,      "HMAC-SHA1" },
 425         { 0, NULL },
 426 };
 427 #endif
 428
 429 /* initialisation routine */
 430 static void rtp_fragment_init(void)
 431 {
 432         fragment_table_init(&fragment_table);
 433         fid_table = g_hash_table_new(g_direct_hash, g_direct_equal);
 434 }
 435
 436 void
 437 rtp_free_hash_dyn_payload(GHashTable *rtp_dyn_payload)
 438 {
 439         if (rtp_dyn_payload == NULL) return;
 440         g_hash_table_destroy(rtp_dyn_payload);
 441         rtp_dyn_payload = NULL;
 442 }
 443
 444 /* Set up an SRTP conversation */
 445 void srtp_add_address(packet_info *pinfo,
 446                      address *addr, int port,
 447                      int other_port,
 448                      const gchar *setup_method, guint32 setup_frame_number, gboolean is_video _U_, GHashTable *rtp_dyn_payload,
 449                      struct srtp_info *srtp_info)
 450 {
 451         address null_addr;
 452         conversation_t* p_conv;
 453         struct _rtp_conversation_info *p_conv_data = NULL;
 454
 455         /*
 456          * If this isn't the first time this packet has been processed,
 457          * we've already done this work, so we don't need to do it
 458          * again.
 459          */
 460         if (pinfo->fd->flags.visited)
 461         {
 462                 return;
 463         }
 464
 465 #ifdef DEBUG
 466         printf("#%u: %srtp_add_address(%s, %u, %u, %s, %u\n", pinfo->fd->num, (srtp_info)?"s":"", ep_address_to_str(addr), port, other_port, setup_method, setup_frame_number);
 467 #endif
 468
 469         SET_ADDRESS(&null_addr, AT_NONE, 0, NULL);
 470
 471         /*
 472          * Check if the ip address and port combination is not
 473          * already registered as a conversation.
 474          */
 475         p_conv = find_conversation( setup_frame_number, addr, &null_addr, PT_UDP, port, other_port,
 476                                 NO_ADDR_B | (!other_port ? NO_PORT_B : 0));
 477
 478         /*
 479          * If not, create a new conversation.
 480          */
 481         if ( !p_conv || p_conv->setup_frame != setup_frame_number) {
 482                 p_conv = conversation_new( setup_frame_number, addr, &null_addr, PT_UDP,
 483                                            (guint32)port, (guint32)other_port,
 484                                                                    NO_ADDR2 | (!other_port ? NO_PORT2 : 0));
 485         }
 486
 487         /* Set dissector */
 488         conversation_set_dissector(p_conv, rtp_handle);
 489
 490         /*
 491          * Check if the conversation has data associated with it.
 492          */
 493         p_conv_data = conversation_get_proto_data(p_conv, proto_rtp);
 494
 495         /*
 496          * If not, add a new data item.
 497          */
 498         if ( ! p_conv_data ) {
 499                 /* Create conversation data */
 500                 p_conv_data = se_alloc(sizeof(struct _rtp_conversation_info));
 501                 p_conv_data->rtp_dyn_payload = NULL;
 502
 503                 /* start this at 0x10000 so that we cope gracefully with the
 504                  * first few packets being out of order (hence 0,65535,1,2,...)
 505                  */
 506                 p_conv_data->extended_seqno = 0x10000;
 507                 p_conv_data->rtp_conv_info = se_alloc(sizeof(rtp_private_conv_info));
 508                 p_conv_data->rtp_conv_info->multisegment_pdus = se_tree_create(EMEM_TREE_TYPE_RED_BLACK,"rtp_ms_pdus");
 509                 conversation_add_proto_data(p_conv, proto_rtp, p_conv_data);
 510         }
 511
 512         /*
 513          * Update the conversation data.
 514          */
 515         /* Free the hash if already exists */
 516         rtp_free_hash_dyn_payload(p_conv_data->rtp_dyn_payload);
 517
 518         g_strlcpy(p_conv_data->method, setup_method, MAX_RTP_SETUP_METHOD_SIZE+1);
 519         p_conv_data->frame_number = setup_frame_number;
 520         p_conv_data->is_video = is_video;
 521         p_conv_data->rtp_dyn_payload = rtp_dyn_payload;
 522         p_conv_data->srtp_info = srtp_info;
 523 }
 524
 525 /* Set up an RTP conversation */
 526 void rtp_add_address(packet_info *pinfo,
 527                      address *addr, int port,
 528                      int other_port,
 529                      const gchar *setup_method, guint32 setup_frame_number, gboolean is_video , GHashTable *rtp_dyn_payload)
 530 {
 531         srtp_add_address(pinfo, addr, port, other_port, setup_method, setup_frame_number, is_video, rtp_dyn_payload, NULL);
 532 }
 533
 534 static gboolean
 535 dissect_rtp_heur( tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree )
 536 {
 537         guint8      octet1, octet2;
 538         unsigned int version;
 539         unsigned int payload_type;
 540         unsigned int offset = 0;
 541
 542         /* This is a heuristic dissector, which means we get all the UDP
 543          * traffic not sent to a known dissector and not claimed by
 544          * a heuristic dissector called before us!
 545          */
 546
 547         if (! global_rtp_heur)
 548                 return FALSE;
 549
 550         /* Get the fields in the first octet */
 551         octet1 = tvb_get_guint8( tvb, offset );
 552         version = RTP_VERSION( octet1 );
 553
 554         if (version == 0) {
 555                 if (!(tvb_memeql(tvb, 4, "ZRTP", 4)))
 556                 {
 557                         call_dissector_only(zrtp_handle, tvb, pinfo, tree);
 558                         return TRUE;
 559                 } else {
 560                         switch (global_rtp_version0_type) {
 561                         case RTP0_CLASSICSTUN:
 562                                 return call_dissector_only(classicstun_heur_handle, tvb, pinfo, tree);
 563
 564                         case RTP0_T38:
 565                                 /* XXX: Should really be calling a heuristic dissector for T38 ??? */
 566                                 call_dissector_only(t38_handle, tvb, pinfo, tree);
 567                                 return TRUE;
 568
 569                         case RTP0_INVALID:
 570
 571                         default:
 572                                 return FALSE; /* Unknown or unsupported version */
 573                         }
 574                 }
 575         } else if (version != 2) {
 576                 /* Unknown or unsupported version */
 577                 return FALSE;
 578         }
 579
 580         /* Was it sent to an even-numbered port? */
 581         if ((pinfo->destport % 2) != 0) {
 582                 return FALSE;
 583         }
 584
 585         /* Get the fields in the second octet */
 586         octet2 = tvb_get_guint8( tvb, offset + 1 );
 587         payload_type = RTP_PAYLOAD_TYPE( octet2 );
 588
 589         /* Check for a sensible payload type
 590            (recognised static and preferred dynamic ranges) */
 591         if ((payload_type <= PT_H263) ||
 592                 /* Alex Lindberg - Modified range to use RTP Type Names */
 593             (payload_type >= PT_UNDF_96 && payload_type <= PT_UNDF_127)) {
 594                 dissect_rtp( tvb, pinfo, tree );
 595                 return TRUE;
 596         }
 597         else {
 598                 return FALSE;
 599         }
 600 }
 601
 602 /*
 603  * Process the payload of the RTP packet, hand it to the subdissector
 604  */
 605 static void
 606 process_rtp_payload(tvbuff_t *newtvb, packet_info *pinfo, proto_tree *tree,
 607                     proto_tree *rtp_tree,
 608                     unsigned int payload_type)
 609 {
 610         struct _rtp_conversation_info *p_conv_data = NULL;
 611         gboolean found_match = FALSE;
 612         int payload_len;
 613         struct srtp_info *srtp_info;
 614         int offset=0;
 615
 616         payload_len = tvb_length_remaining(newtvb, offset);
 617
 618         /* first check if this is added as an SRTP stream - if so, don't try to dissector the payload data for now */
 619         p_conv_data = p_get_proto_data(pinfo->fd, proto_rtp);
 620         if (p_conv_data && p_conv_data->srtp_info) {
 621                 srtp_info = p_conv_data->srtp_info;
 622                 payload_len -= srtp_info->mki_len + srtp_info->auth_tag_len;
 623 #if 0
 624 #error Currently the srtp_info structure contains no cypher data, see packet-sdp.c adding dummy_srtp_info structure
 625                 if (p_conv_data->srtp_info->encryption_algorithm==SRTP_ENC_ALG_NULL) {
 626                         if (rtp_tree)
 627                                 proto_tree_add_text(rtp_tree, newtvb, offset, payload_len, "SRTP Payload with NULL encryption");
 628                 }
 629                 else
 630 #endif
 631                 {
 632                         if (rtp_tree)
 633                                 proto_tree_add_item(rtp_tree, hf_srtp_encrypted_payload, newtvb, offset, payload_len, FALSE);
 634                         found_match = TRUE;     /* use this flag to prevent dissection below */
 635                 }
 636                 offset += payload_len;
 637
 638                 if (srtp_info->mki_len) {
 639                         proto_tree_add_item(rtp_tree, hf_srtp_mki, newtvb, offset, srtp_info->mki_len, FALSE);
 640                         offset += srtp_info->mki_len;
 641                 }
 642
 643                 if (srtp_info->auth_tag_len) {
 644                         proto_tree_add_item(rtp_tree, hf_srtp_auth_tag, newtvb, offset, srtp_info->auth_tag_len, FALSE);
 645                         offset += srtp_info->auth_tag_len;
 646                 }
 647         }
 648
 649         /* if the payload type is dynamic, we check if the conv is set and we look for the pt definition */
 650         else if ( (payload_type >= PT_UNDF_96 && payload_type <= PT_UNDF_127) ) {
 651                 if (p_conv_data && p_conv_data->rtp_dyn_payload) {
 652                         gchar *payload_type_str = NULL;
 653                         payload_type_str = g_hash_table_lookup(p_conv_data->rtp_dyn_payload, &payload_type);
 654                         if (payload_type_str){
 655                                 found_match = dissector_try_string(rtp_dyn_pt_dissector_table,
 656                                                                    payload_type_str, newtvb, pinfo, tree);
 657                                 /* If payload type string set from conversation and
 658                                  * no matching dissector found it's probably because no subdissector
 659                                  * exists. Don't call the dissectors based on payload number
 660                                  * as that'd probably be the wrong dissector in this case.
 661                                  * Just add it as data.
 662                                  */
 663                                 if(found_match==FALSE)
 664                                         proto_tree_add_item( rtp_tree, hf_rtp_data, newtvb, 0, -1, FALSE );
 665                                 return;
 666                         }
 667
 668                 }
 669         }
 670
 671         /* if we don't found, it is static OR could be set static from the preferences */
 672         if (!found_match && !dissector_try_port(rtp_pt_dissector_table, payload_type, newtvb, pinfo, tree))
 673                 proto_tree_add_item( rtp_tree, hf_rtp_data, newtvb, 0, -1, FALSE );
 674
 675 }
 676
 677 /* Rtp payload reassembly
 678  *
 679  * This handles the reassembly of PDUs for higher-level protocols.
 680  *
 681  * We're a bit limited on how we can cope with out-of-order packets, because
 682  * we don't have any idea of where the datagram boundaries are. So if we see
 683  * packets A, C, B (all of which comprise a single datagram), we cannot know
 684  * that C should be added to the same datagram as A, until we come to B (which
 685  * may or may not actually be present...).
 686  *
 687  * What we end up doing in this case is passing A+B to the subdissector as one
 688  * datagram, and make out that a new one starts on C.
 689  */
 690 static void
 691 dissect_rtp_data( tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree,
 692                   proto_tree *rtp_tree, int offset, unsigned int data_len,
 693                   unsigned int data_reported_len,
 694                   unsigned int payload_type )
 695 {
 696         tvbuff_t *newtvb;
 697         struct _rtp_conversation_info *p_conv_data= NULL;
 698         gboolean must_desegment = FALSE;
 699         rtp_private_conv_info *finfo = NULL;
 700         rtp_multisegment_pdu *msp = NULL;
 701         guint32 seqno;
 702
 703         /* Retrieve RTPs idea of a converation */
 704         p_conv_data = p_get_proto_data(pinfo->fd, proto_rtp);
 705
 706         if(p_conv_data != NULL)
 707                 finfo = p_conv_data->rtp_conv_info;
 708
 709         if(finfo == NULL || !desegment_rtp) {
 710                 /* Hand the whole lot off to the subdissector */
 711                 newtvb=tvb_new_subset(tvb,offset,data_len,data_reported_len);
 712                 process_rtp_payload(newtvb, pinfo, tree, rtp_tree, payload_type);
 713                 return;
 714         }
 715
 716         seqno = p_conv_data->extended_seqno;
 717
 718         pinfo->can_desegment = 2;
 719         pinfo->desegment_offset = 0;
 720         pinfo->desegment_len = 0;
 721
 722 #ifdef DEBUG_FRAGMENTS
 723         g_debug("%d: RTP Part of convo %d(%p); seqno %d",
 724                 pinfo->fd->num,
 725                 p_conv_data->frame_number, p_conv_data,
 726                 seqno
 727                 );
 728 #endif
 729
 730         /* look for a pdu which we might be extending */
 731         msp = (rtp_multisegment_pdu *)se_tree_lookup32_le(finfo->multisegment_pdus,seqno-1);
 732
 733         if(msp && msp->startseq < seqno && msp->endseq >= seqno) {
 734                 guint32 fid = msp->startseq;
 735                 fragment_data *fd_head;
 736
 737 #ifdef DEBUG_FRAGMENTS
 738                 g_debug("\tContinues fragment %d", fid);
 739 #endif
 740
 741                 /* we always assume the datagram is complete; if this is the
 742                  * first pass, that's our best guess, and if it's not, what we
 743                  * say gets ignored anyway.
 744                  */
 745                 fd_head = fragment_add_seq(tvb, offset, pinfo, fid, fragment_table,
 746                                            seqno-msp->startseq, data_len, FALSE);
 747
 748                 newtvb = process_reassembled_data(tvb,offset, pinfo, "Reassembled RTP", fd_head,
 749                                                   &rtp_fragment_items, NULL, tree);
 750
 751 #ifdef DEBUG_FRAGMENTS
 752                 g_debug("\tFragment Coalesced; fd_head=%p, newtvb=%p (len %d)",fd_head, newtvb,
 753                         newtvb?tvb_reported_length(newtvb):0);
 754 #endif
 755
 756                 if(newtvb != NULL) {
 757                         /* Hand off to the subdissector */
 758                         process_rtp_payload(newtvb, pinfo, tree, rtp_tree, payload_type);
 759
 760                         /*
 761                          * Check to see if there were any complete fragments within the chunk
 762                          */
 763                         if( pinfo->desegment_len && pinfo->desegment_offset == 0 )
 764                         {
 765 #ifdef DEBUG_FRAGMENTS
 766                                 g_debug("\tNo complete pdus in payload" );
 767 #endif
 768                                 /* Mark the fragments and not complete yet */
 769                                 fragment_set_partial_reassembly(pinfo, fid, fragment_table);
 770
 771                                 /* we must need another segment */
 772                                 msp->endseq = MIN(msp->endseq,seqno) + 1;
 773                         }
 774                         else
 775                         {
 776                                 /*
 777                                  * Data was dissected so add the protocol tree to the display
 778                                  */
 779                                 proto_item *rtp_tree_item, *frag_tree_item;
 780                                 /* this nargery is to insert the fragment tree into the main tree
 781                                  * between the RTP protocol entry and the subdissector entry */
 782                                 show_fragment_tree(fd_head, &rtp_fragment_items, tree, pinfo, newtvb, &frag_tree_item);
 783                                 rtp_tree_item = proto_item_get_parent( proto_tree_get_parent( rtp_tree ));
 784                                 if( frag_tree_item && rtp_tree_item )
 785                                         proto_tree_move_item( tree, rtp_tree_item, frag_tree_item );
 786
 787
 788                                 if(pinfo->desegment_len)
 789                                 {
 790                                         /* the higher-level dissector has asked for some more data - ie,
 791                                            the end of this segment does not coincide with the end of a
 792                                            higher-level PDU. */
 793                                         must_desegment = TRUE;
 794                                 }
 795                         }
 796
 797                 }
 798
 799         }
 800         else
 801         {
 802                 /*
 803                  * The segment is not the continuation of a fragmented segment
 804                  * so process it as normal
 805                  */
 806 #ifdef DEBUG_FRAGMENTS
 807                 g_debug("\tRTP non-fragment payload");
 808 #endif
 809                 newtvb = tvb_new_subset( tvb, offset, data_len, data_reported_len );
 810
 811                 /* Hand off to the subdissector */
 812                 process_rtp_payload(newtvb, pinfo, tree, rtp_tree, payload_type);
 813
 814                 if(pinfo->desegment_len) {
 815                         /* the higher-level dissector has asked for some more data - ie,
 816                            the end of this segment does not coincide with the end of a
 817                            higher-level PDU. */
 818                         must_desegment = TRUE;
 819                 }
 820         }
 821
 822         /*
 823          * There were bytes left over that the higher protocol couldn't dissect so save them
 824          */
 825         if(must_desegment)
 826         {
 827                 guint32 deseg_offset = pinfo->desegment_offset;
 828                 guint32 frag_len = tvb_reported_length_remaining(newtvb, deseg_offset);
 829                 fragment_data *fd_head = NULL;
 830
 831 #ifdef DEBUG_FRAGMENTS
 832                 g_debug("\tRTP Must Desegment: tvb_len=%d ds_len=%d %d frag_len=%d ds_off=%d",
 833                         tvb_reported_length(newtvb),
 834                         pinfo->desegment_len,
 835                         pinfo->fd->flags.visited,
 836                         frag_len,
 837                         deseg_offset);
 838 #endif
 839                 /* allocate a new msp for this pdu */
 840                 msp = se_alloc(sizeof(rtp_multisegment_pdu));
 841                 msp->startseq = seqno;
 842                 msp->endseq = seqno+1;
 843                 se_tree_insert32(finfo->multisegment_pdus,seqno,msp);
 844
 845                 /*
 846                  * Add the fragment to the fragment table
 847                  */
 848                 fd_head = fragment_add_seq(newtvb,deseg_offset, pinfo, seqno, fragment_table, 0, frag_len,
 849                                            TRUE );
 850
 851                 if(fd_head != NULL)
 852                 {
 853                         if( fd_head->reassembled_in != 0 && !(fd_head->flags & FD_PARTIAL_REASSEMBLY) )
 854                         {
 855                                 proto_item *rtp_tree_item;
 856                                 rtp_tree_item = proto_tree_add_uint( tree, hf_rtp_reassembled_in,
 857                                                                      newtvb, deseg_offset, tvb_reported_length_remaining(newtvb,deseg_offset),
 858                                                                      fd_head->reassembled_in);
 859                                 PROTO_ITEM_SET_GENERATED(rtp_tree_item);
 860 #ifdef DEBUG_FRAGMENTS
 861                                 g_debug("\tReassembled in %d", fd_head->reassembled_in);
 862 #endif
 863                         }
 864                         else
 865                         {
 866 #ifdef DEBUG_FRAGMENTS
 867                                 g_debug("\tUnfinished fragment");
 868 #endif
 869                                 /* this fragment is never reassembled */
 870                                 proto_tree_add_text( tree, tvb, deseg_offset, -1,"RTP fragment, unfinished");
 871                         }
 872                 }
 873                 else
 874                 {
 875                         /*
 876                          * This fragment was the first fragment in a new entry in the
 877                          * frag_table; we don't yet know where it is reassembled
 878                          */
 879 #ifdef DEBUG_FRAGMENTS
 880                         g_debug("\tnew pdu");
 881 #endif
 882                 }
 883
 884                 if( pinfo->desegment_offset == 0 )
 885                 {
 886                         col_set_str(pinfo->cinfo, COL_PROTOCOL, "RTP");
 887                         col_set_str(pinfo->cinfo, COL_INFO, "[RTP segment of a reassembled PDU]");
 888                 }
 889         }
 890
 891
 892
 893         pinfo->can_desegment = 0;
 894         pinfo->desegment_offset = 0;
 895         pinfo->desegment_len = 0;
 896 }
 897
 898
 899
 900 static void
 901 dissect_rtp_rfc2198(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree )
 902 {
 903         int offset = 0;
 904         guint8 octet1;
 905         int cnt;
 906         gboolean hdr_follow = TRUE;
 907         proto_item *ti = NULL;
 908         proto_tree *rfc2198_tree = NULL;
 909         proto_tree *rfc2198_hdr_tree = NULL;
 910         rfc2198_hdr *hdr_last, *hdr_new;
 911         rfc2198_hdr *hdr_chain = NULL;
 912         struct _rtp_conversation_info *p_conv_data= NULL;
 913         gchar *payload_type_str;
 914
 915         /* Retrieve RTPs idea of a converation */
 916         p_conv_data = p_get_proto_data(pinfo->fd, proto_rtp);
 917
 918         /* Add try to RFC 2198 data */
 919         ti = proto_tree_add_text(tree, tvb, offset, -1, "RFC 2198: Redundant Audio Data");
 920         rfc2198_tree = proto_item_add_subtree(ti, ett_rtp_rfc2198);
 921
 922         hdr_last = NULL;
 923         cnt = 0;
 924         while (hdr_follow) {
 925                 cnt++;
 926                 payload_type_str = NULL;
 927
 928                 /* Allocate and fill in header */
 929                 hdr_new = ep_alloc(sizeof(rfc2198_hdr));
 930                 hdr_new->next = NULL;
 931                 octet1 = tvb_get_guint8(tvb, offset);
 932                 hdr_new->pt = RTP_PAYLOAD_TYPE(octet1);
 933                 hdr_follow = (octet1 & 0x80);
 934
 935                 /* if it is dynamic payload, let use the conv data to see if it is defined */
 936                 if ((hdr_new->pt > 95) && (hdr_new->pt < 128)) {
 937                         if (p_conv_data && p_conv_data->rtp_dyn_payload){
 938                                 payload_type_str = g_hash_table_lookup(p_conv_data->rtp_dyn_payload, &hdr_new->pt);
 939                         }
 940                 }
 941                 /* Add a subtree for this header and add items */
 942                 ti = proto_tree_add_text(rfc2198_tree, tvb, offset, (hdr_follow)?4:1, "Header %u", cnt);
 943                 rfc2198_hdr_tree = proto_item_add_subtree(ti, ett_rtp_rfc2198_hdr);
 944                 proto_tree_add_item(rfc2198_hdr_tree, hf_rtp_rfc2198_follow, tvb, offset, 1, FALSE );
 945                 proto_tree_add_uint_format(rfc2198_hdr_tree, hf_rtp_payload_type, tvb,
 946                     offset, 1, octet1, "Payload type: %s (%u)",
 947                         payload_type_str ? payload_type_str : val_to_str(hdr_new->pt, rtp_payload_type_vals, "Unknown"),
 948                         hdr_new->pt);
 949                 proto_item_append_text(ti, ": PT=%s",
 950                                        payload_type_str ? payload_type_str :
 951                                                           val_to_str(hdr_new->pt, rtp_payload_type_vals, "Unknown (%u)"));
 952                 offset += 1;
 953
 954                 /* Timestamp offset and block length don't apply to last header */
 955                 if (hdr_follow) {
 956                         proto_tree_add_item(rfc2198_hdr_tree, hf_rtp_rfc2198_tm_off, tvb, offset, 2, FALSE );
 957                         proto_tree_add_item(rfc2198_hdr_tree, hf_rtp_rfc2198_bl_len, tvb, offset + 1, 2, FALSE );
 958                         hdr_new->len = tvb_get_ntohs(tvb, offset + 1) & 0x03FF;
 959                         proto_item_append_text(ti, ", len=%u", hdr_new->len);
 960                         offset += 3;
 961                 } else {
 962                         hdr_new->len = -1;
 963                         hdr_follow = FALSE;
 964                 }
 965
 966                 if (hdr_last) {
 967                         hdr_last->next = hdr_new;
 968                 } else {
 969                         hdr_chain = hdr_new;
 970                 }
 971                 hdr_last = hdr_new;
 972         }
 973
 974         /* Dissect each data block according to the header info */
 975         hdr_last = hdr_chain;
 976         while (hdr_last) {
 977                 hdr_last->offset = offset;
 978                 if (!hdr_last->next) {
 979                         hdr_last->len = tvb_reported_length_remaining(tvb, offset);
 980                 }
 981                 dissect_rtp_data(tvb, pinfo, tree, rfc2198_tree, hdr_last->offset, hdr_last->len, hdr_last->len, hdr_last->pt);
 982                 offset += hdr_last->len;
 983                 hdr_last = hdr_last->next;
 984         }
 985 }
 986
 987 static void
 988 dissect_rtp( tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree )
 989 {
 990         proto_item *ti            = NULL;
 991         proto_tree *rtp_tree      = NULL;
 992         proto_tree *rtp_csrc_tree = NULL;
 993         proto_tree *rtp_hext_tree = NULL;
 994         guint8      octet1, octet2;
 995         unsigned int version;
 996         gboolean    padding_set;
 997         gboolean    extension_set;
 998         unsigned int csrc_count;
 999         gboolean    marker_set;
1000         unsigned int payload_type;
1001         gchar *payload_type_str = NULL;
1002         gboolean    is_srtp = FALSE;
1003         unsigned int i            = 0;
1004         unsigned int hdr_extension= 0;
1005         unsigned int padding_count;
1006         gint        length, reported_length;
1007         int         data_len;
1008         unsigned int offset = 0;
1009         guint16     seq_num;
1010         guint32     timestamp;
1011         guint32     sync_src;
1012         guint32     csrc_item;
1013         struct _rtp_conversation_info *p_conv_data = NULL;
1014         struct srtp_info *srtp_info = NULL;
1015         unsigned int srtp_offset;
1016         unsigned int hdrext_offset = 0;
1017         tvbuff_t *newtvb = NULL;
1018
1019         /* Can tap up to 4 RTP packets within same packet */
1020         static struct _rtp_info rtp_info_arr[4];
1021         static int rtp_info_current=0;
1022         struct _rtp_info *rtp_info;
1023
1024         rtp_info_current++;
1025         if (rtp_info_current==4) {
1026                 rtp_info_current=0;
1027         }
1028         rtp_info = &rtp_info_arr[rtp_info_current];
1029
1030         /* Get the fields in the first octet */
1031         octet1 = tvb_get_guint8( tvb, offset );
1032         version = RTP_VERSION( octet1 );
1033
1034         if (version == 0) {
1035                 switch (global_rtp_version0_type) {
1036                 case RTP0_CLASSICSTUN:
1037                         call_dissector(classicstun_handle, tvb, pinfo, tree);
1038                         return;
1039
1040                 case RTP0_T38:
1041                         call_dissector(t38_handle, tvb, pinfo, tree);
1042                         return;
1043
1044                 case RTP0_INVALID:
1045                         if (!(tvb_memeql(tvb, 4, "ZRTP", 4)))
1046                         {
1047                                 call_dissector(zrtp_handle,tvb,pinfo,tree);
1048                                 return;
1049                         }
1050                 default:
1051                         ; /* Unknown or unsupported version (let it fall through) */
1052                 }
1053         }
1054
1055         /* fill in the rtp_info structure */
1056         rtp_info->info_version = version;
1057         if (version != 2) {
1058                 /*
1059                  * Unknown or unsupported version.
1060                  */
1061                 col_set_str(pinfo->cinfo, COL_PROTOCOL, "RTP");
1062
1063                 if ( check_col( pinfo->cinfo, COL_INFO) ) {
1064                         col_add_fstr( pinfo->cinfo, COL_INFO,
1065                             "Unknown RTP version %u", version);
1066                 }
1067
1068                 if ( tree ) {
1069                         ti = proto_tree_add_item( tree, proto_rtp, tvb, offset, -1, FALSE );
1070                         rtp_tree = proto_item_add_subtree( ti, ett_rtp );
1071
1072                         proto_tree_add_uint( rtp_tree, hf_rtp_version, tvb,
1073                             offset, 1, octet1);
1074                 }
1075                 return;
1076         }
1077
1078         padding_set = RTP_PADDING( octet1 );
1079         extension_set = RTP_EXTENSION( octet1 );
1080         csrc_count = RTP_CSRC_COUNT( octet1 );
1081
1082         /* Get the fields in the second octet */
1083         octet2 = tvb_get_guint8( tvb, offset + 1 );
1084         marker_set = RTP_MARKER( octet2 );
1085         payload_type = RTP_PAYLOAD_TYPE( octet2 );
1086
1087         /* Get the subsequent fields */
1088         seq_num = tvb_get_ntohs( tvb, offset + 2 );
1089         timestamp = tvb_get_ntohl( tvb, offset + 4 );
1090         sync_src = tvb_get_ntohl( tvb, offset + 8 );
1091
1092         /* fill in the rtp_info structure */
1093         rtp_info->info_padding_set = padding_set;
1094         rtp_info->info_padding_count = 0;
1095         rtp_info->info_marker_set = marker_set;
1096         rtp_info->info_is_video = FALSE;
1097         rtp_info->info_payload_type = payload_type;
1098         rtp_info->info_seq_num = seq_num;
1099         rtp_info->info_timestamp = timestamp;
1100         rtp_info->info_sync_src = sync_src;
1101         rtp_info->info_is_srtp = FALSE;
1102         rtp_info->info_setup_frame_num = 0;
1103         rtp_info->info_payload_type_str = NULL;
1104
1105         /*
1106          * Do we have all the data?
1107          */
1108         length = tvb_length_remaining(tvb, offset);
1109         reported_length = tvb_reported_length_remaining(tvb, offset);
1110         if (reported_length >= 0 && length >= reported_length) {
1111                 /*
1112                  * Yes.
1113                  */
1114                 rtp_info->info_all_data_present = TRUE;
1115                 rtp_info->info_data_len = reported_length;
1116
1117                 /*
1118                  * Save the pointer to raw rtp data (header + payload incl.
1119                  * padding).
1120                  * That should be safe because the "epan_dissect_t"
1121                  * constructed for the packet has not yet been freed when
1122                  * the taps are called.
1123                  * (Destroying the "epan_dissect_t" will end up freeing
1124                  * all the tvbuffs and hence invalidating pointers to
1125                  * their data.)
1126                  * See "add_packet_to_packet_list()" for details.
1127                  */
1128                 rtp_info->info_data = tvb_get_ptr(tvb, 0, -1);
1129         } else {
1130                 /*
1131                  * No - packet was cut short at capture time.
1132                  */
1133                 rtp_info->info_all_data_present = FALSE;
1134                 rtp_info->info_data_len = 0;
1135                 rtp_info->info_data = NULL;
1136         }
1137
1138         /* Look for conv and add to the frame if found */
1139         get_conv_info(pinfo, rtp_info);
1140         p_conv_data = p_get_proto_data(pinfo->fd, proto_rtp);
1141
1142         if (p_conv_data)
1143                 rtp_info->info_is_video = p_conv_data->is_video;
1144
1145         if (p_conv_data && p_conv_data->srtp_info) is_srtp = TRUE;
1146         rtp_info->info_is_srtp = is_srtp;
1147
1148         if ( check_col( pinfo->cinfo, COL_PROTOCOL ) )   {
1149                 col_set_str( pinfo->cinfo, COL_PROTOCOL, (is_srtp) ? "SRTP" : "RTP" );
1150         }
1151
1152         /* check if this is added as an SRTP stream - if so, don't try to dissector the payload data for now */
1153         p_conv_data = p_get_proto_data(pinfo->fd, proto_rtp);
1154
1155
1156         if (p_conv_data && p_conv_data->srtp_info) {
1157                 srtp_info = p_conv_data->srtp_info;
1158                 if (rtp_info->info_all_data_present) {
1159                         srtp_offset = rtp_info->info_data_len - srtp_info->mki_len - srtp_info->auth_tag_len;
1160                 }
1161         }
1162
1163         /* if it is dynamic payload, let use the conv data to see if it is defined */
1164         if ( (payload_type>95) && (payload_type<128) ) {
1165                 if (p_conv_data && p_conv_data->rtp_dyn_payload){
1166                         payload_type_str = g_hash_table_lookup(p_conv_data->rtp_dyn_payload, &payload_type);
1167                         rtp_info->info_payload_type_str = payload_type_str;
1168                 }
1169         }
1170
1171         if ( check_col( pinfo->cinfo, COL_INFO) ) {
1172                 col_add_fstr( pinfo->cinfo, COL_INFO,
1173                     "PT=%s, SSRC=0x%X, Seq=%u, Time=%u%s",
1174                         payload_type_str ? payload_type_str : val_to_str( payload_type, rtp_payload_type_vals,"Unknown (%u)" ),
1175                     sync_src,
1176                     seq_num,
1177                     timestamp,
1178                     marker_set ? ", Mark " : " ");
1179         }
1180
1181
1182         if ( tree ) {
1183                 proto_tree *item;
1184                 /* Create RTP protocol tree */
1185                 ti = proto_tree_add_item(tree, proto_rtp, tvb, offset, -1, FALSE );
1186                 rtp_tree = proto_item_add_subtree(ti, ett_rtp );
1187
1188                 /* Conversation setup info */
1189                 if (global_rtp_show_setup_info)
1190                 {
1191                         show_setup_info(tvb, pinfo, rtp_tree);
1192                 }
1193
1194                 proto_tree_add_uint( rtp_tree, hf_rtp_version, tvb,
1195                     offset, 1, octet1 );
1196                 proto_tree_add_boolean( rtp_tree, hf_rtp_padding, tvb,
1197                     offset, 1, octet1 );
1198                 proto_tree_add_boolean( rtp_tree, hf_rtp_extension, tvb,
1199                     offset, 1, octet1 );
1200                 proto_tree_add_uint( rtp_tree, hf_rtp_csrc_count, tvb,
1201                     offset, 1, octet1 );
1202                 offset++;
1203
1204                 proto_tree_add_boolean( rtp_tree, hf_rtp_marker, tvb, offset,
1205                     1, octet2 );
1206
1207                 item = proto_tree_add_uint_format( rtp_tree, hf_rtp_payload_type, tvb,
1208                     offset, 1, octet2, "Payload type: %s (%u)",
1209                         payload_type_str ? payload_type_str : val_to_str( payload_type, rtp_payload_type_vals,"Unknown"),
1210                         payload_type);
1211
1212                 offset++;
1213
1214                 /* Sequence number 16 bits (2 octets) */
1215                 proto_tree_add_uint( rtp_tree, hf_rtp_seq_nr, tvb, offset, 2, seq_num );
1216                 if(p_conv_data != NULL) {
1217                         item = proto_tree_add_uint( rtp_tree, hf_rtp_ext_seq_nr, tvb, offset, 2, p_conv_data->extended_seqno );
1218                         PROTO_ITEM_SET_GENERATED(item);
1219                 }
1220                 offset += 2;
1221
1222                 /* Timestamp 32 bits (4 octets) */
1223                 proto_tree_add_uint( rtp_tree, hf_rtp_timestamp, tvb, offset, 4, timestamp );
1224                 offset += 4;
1225
1226                 /* Synchronization source identifier 32 bits (4 octets) */
1227                 proto_tree_add_uint( rtp_tree, hf_rtp_ssrc, tvb, offset, 4, sync_src );
1228                 offset += 4;
1229         } else {
1230                 offset += 12;
1231         }
1232         /* CSRC list*/
1233         if ( csrc_count > 0 ) {
1234                 if ( tree ) {
1235                         ti = proto_tree_add_item(rtp_tree, hf_rtp_csrc_items, tvb, offset,
1236                                                  csrc_count * 4, FALSE);
1237                         proto_item_append_text(ti, " (%u items)", csrc_count);
1238                         rtp_csrc_tree = proto_item_add_subtree( ti, ett_csrc_list );
1239                 }
1240                 for (i = 0; i < csrc_count; i++ ) {
1241                         csrc_item = tvb_get_ntohl( tvb, offset );
1242                         if ( tree ) proto_tree_add_uint_format( rtp_csrc_tree,
1243                             hf_rtp_csrc_item, tvb, offset, 4,
1244                             csrc_item,
1245                             "CSRC item %d: 0x%X",
1246                             i, csrc_item );
1247                         offset += 4;
1248                 }
1249         }
1250
1251         /* Optional RTP header extension */
1252         if ( extension_set ) {
1253                 /* Defined by profile field is 16 bits (2 octets) */
1254                 if ( tree ) proto_tree_add_uint( rtp_tree, hf_rtp_prof_define, tvb, offset, 2, tvb_get_ntohs( tvb, offset ) );
1255                 offset += 2;
1256
1257                 hdr_extension = tvb_get_ntohs( tvb, offset );
1258                 if ( tree ) proto_tree_add_uint( rtp_tree, hf_rtp_length, tvb, offset, 2, hdr_extension);
1259                 offset += 2;
1260                 if ( hdr_extension > 0 ) {
1261                         if ( tree ) {
1262                                 ti = proto_tree_add_item(rtp_tree, hf_rtp_hdr_exts, tvb, offset, hdr_extension * 4, FALSE);
1263                                 rtp_hext_tree = proto_item_add_subtree( ti, ett_hdr_ext );
1264                         }
1265
1266                         /* pass interpretation of header extension to a registered subdissector */
1267                         newtvb = tvb_new_subset(tvb, offset, hdr_extension * 4, hdr_extension * 4);
1268                         if ( !(rtp_info->info_payload_type_str && dissector_try_string(rtp_hdr_ext_dissector_table,
1269                                 rtp_info->info_payload_type_str, newtvb, pinfo, rtp_hext_tree)) ) {
1270                                 hdrext_offset = offset;
1271                                 for ( i = 0; i < hdr_extension; i++ ) {
1272                                         if ( tree ) proto_tree_add_uint( rtp_hext_tree, hf_rtp_hdr_ext, tvb, hdrext_offset, 4, tvb_get_ntohl( tvb, hdrext_offset ) );
1273                                         hdrext_offset += 4;
1274                                 }
1275                         }
1276                         offset += hdr_extension * 4;
1277                 }
1278         }
1279
1280         if ( padding_set ) {
1281                 /*
1282                  * This RTP frame has padding - find it.
1283                  *
1284                  * The padding count is found in the LAST octet of
1285                  * the packet; it contains the number of octets
1286                  * that can be ignored at the end of the packet.
1287                  */
1288                 if (tvb_length(tvb) < tvb_reported_length(tvb)) {
1289                         /*
1290                          * We don't *have* the last octet of the
1291                          * packet, so we can't get the padding
1292                          * count.
1293                          *
1294                          * Put an indication of that into the
1295                          * tree, and just put in a raw data
1296                          * item.
1297                          */
1298                         if ( tree ) proto_tree_add_text(rtp_tree, tvb, 0, 0,
1299                             "Frame has padding, but not all the frame data was captured");
1300                         call_dissector(data_handle,
1301                             tvb_new_subset_remaining(tvb, offset),
1302                             pinfo, rtp_tree);
1303                         return;
1304                 }
1305
1306                 padding_count = tvb_get_guint8( tvb,
1307                     tvb_reported_length( tvb ) - 1 );
1308                 data_len =
1309                     tvb_reported_length_remaining( tvb, offset ) - padding_count;
1310
1311                 rtp_info->info_payload_offset = offset;
1312                 rtp_info->info_payload_len = tvb_length_remaining(tvb, offset);
1313                 rtp_info->info_padding_count = padding_count;
1314
1315                 if (data_len > 0) {
1316                         /*
1317                          * There's data left over when you take out
1318                          * the padding; dissect it.
1319                          */
1320                         dissect_rtp_data( tvb, pinfo, tree, rtp_tree,
1321                             offset,
1322                             data_len,
1323                             data_len,
1324                             payload_type );
1325                         offset += data_len;
1326                 } else if (data_len < 0) {
1327                         /*
1328                          * The padding count is bigger than the
1329                          * amount of RTP payload in the packet!
1330                          * Clip the padding count.
1331                          *
1332                          * XXX - put an item in the tree to indicate
1333                          * that the padding count is bogus?
1334                          */
1335                         padding_count =
1336                             tvb_reported_length_remaining(tvb, offset);
1337                 }
1338                 if (padding_count > 1) {
1339                         /*
1340                          * There's more than one byte of padding;
1341                          * show all but the last byte as padding
1342                          * data.
1343                          */
1344                         if ( tree ) proto_tree_add_item( rtp_tree, hf_rtp_padding_data,
1345                             tvb, offset, padding_count - 1, FALSE );
1346                         offset += padding_count - 1;
1347                 }
1348                 /*
1349                  * Show the last byte in the PDU as the padding
1350                  * count.
1351                  */
1352                 if ( tree ) proto_tree_add_item( rtp_tree, hf_rtp_padding_count,
1353                     tvb, offset, 1, FALSE );
1354         }
1355         else {
1356                 /*
1357                  * No padding.
1358                  */
1359                 dissect_rtp_data( tvb, pinfo, tree, rtp_tree, offset,
1360                                   tvb_length_remaining( tvb, offset ),
1361                                   tvb_reported_length_remaining( tvb, offset ),
1362                                   payload_type );
1363                 rtp_info->info_payload_offset = offset;
1364                 rtp_info->info_payload_len = tvb_length_remaining(tvb, offset);
1365         }
1366         if (!pinfo->in_error_pkt)
1367                 tap_queue_packet(rtp_tap, pinfo, rtp_info);
1368 }
1369
1370
1371 /* calculate the extended sequence number - top 16 bits of the previous sequence number,
1372  * plus our own; then correct for wrapping */
1373 static guint32 calculate_extended_seqno(guint32 previous_seqno, guint16 raw_seqno)
1374 {
1375         guint32 seqno = (previous_seqno & 0xffff0000) | raw_seqno;
1376         if(seqno + 0x8000 < previous_seqno) {
1377                 seqno += 0x10000;
1378         } else if(previous_seqno + 0x8000 < seqno) {
1379                 /* we got an out-of-order packet which happened to go backwards over the
1380                  * wrap boundary */
1381                 seqno -= 0x10000;
1382         }
1383         return seqno;
1384 }
1385
1386 /* Look for conversation info */
1387 static void get_conv_info(packet_info *pinfo, struct _rtp_info *rtp_info)
1388 {
1389         /* Conversation and current data */
1390         conversation_t *p_conv = NULL;
1391         struct _rtp_conversation_info *p_conv_data = NULL;
1392
1393         /* Use existing packet info if available */
1394         p_conv_data = p_get_proto_data(pinfo->fd, proto_rtp);
1395
1396         if (!p_conv_data)
1397         {
1398                 /* First time, get info from conversation */
1399                 p_conv = find_conversation(pinfo->fd->num, &pinfo->net_dst, &pinfo->net_src,
1400                                            pinfo->ptype,
1401                                            pinfo->destport, pinfo->srcport, NO_ADDR_B);
1402                 if (p_conv)
1403                 {
1404                         /* Create space for packet info */
1405                         struct _rtp_conversation_info *p_conv_packet_data;
1406                         p_conv_data = conversation_get_proto_data(p_conv, proto_rtp);
1407
1408                         if (p_conv_data) {
1409                                 guint32 seqno;
1410
1411                                 /* Save this conversation info into packet info */
1412                                 p_conv_packet_data = se_alloc(sizeof(struct _rtp_conversation_info));
1413                                 g_strlcpy(p_conv_packet_data->method, p_conv_data->method, MAX_RTP_SETUP_METHOD_SIZE+1);
1414                                 p_conv_packet_data->frame_number = p_conv_data->frame_number;
1415                                 p_conv_packet_data->is_video = p_conv_data->is_video;
1416                                 p_conv_packet_data->rtp_dyn_payload = p_conv_data->rtp_dyn_payload;
1417                                 p_conv_packet_data->rtp_conv_info = p_conv_data->rtp_conv_info;
1418                                 p_conv_packet_data->srtp_info = p_conv_data->srtp_info;
1419                                 p_add_proto_data(pinfo->fd, proto_rtp, p_conv_packet_data);
1420
1421                                 /* calculate extended sequence number */
1422                                 seqno = calculate_extended_seqno(p_conv_data->extended_seqno,
1423                                                                  rtp_info->info_seq_num);
1424
1425                                 p_conv_packet_data->extended_seqno = seqno;
1426                                 p_conv_data->extended_seqno = seqno;
1427                         }
1428                 }
1429         }
1430         if (p_conv_data) rtp_info->info_setup_frame_num = p_conv_data->frame_number;
1431 }
1432
1433
1434 /* Display setup info */
1435 static void show_setup_info(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
1436 {
1437         /* Conversation and current data */
1438         struct _rtp_conversation_info *p_conv_data = NULL;
1439         proto_tree *rtp_setup_tree;
1440         proto_item *ti;
1441
1442         /* Use existing packet info if available */
1443         p_conv_data = p_get_proto_data(pinfo->fd, proto_rtp);
1444
1445         if (!p_conv_data) return;
1446
1447         /* Create setup info subtree with summary info. */
1448         ti =  proto_tree_add_string_format(tree, hf_rtp_setup, tvb, 0, 0,
1449                                                                "",
1450                                                                "Stream setup by %s (frame %u)",
1451                                                                p_conv_data->method,
1452                                                                p_conv_data->frame_number);
1453                 PROTO_ITEM_SET_GENERATED(ti);
1454                 rtp_setup_tree = proto_item_add_subtree(ti, ett_rtp_setup);
1455                 if (rtp_setup_tree)
1456                 {
1457                         /* Add details into subtree */
1458                         proto_item* item = proto_tree_add_uint(rtp_setup_tree, hf_rtp_setup_frame,
1459                                                                tvb, 0, 0, p_conv_data->frame_number);
1460                         PROTO_ITEM_SET_GENERATED(item);
1461                         item = proto_tree_add_string(rtp_setup_tree, hf_rtp_setup_method,
1462                                                      tvb, 0, 0, p_conv_data->method);
1463                         PROTO_ITEM_SET_GENERATED(item);
1464                 }
1465 }
1466
1467 /* Dissect PacketCable CCC header */
1468
1469 static void
1470 dissect_pkt_ccc(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
1471 {
1472         proto_item *ti            = NULL;
1473         proto_tree *pkt_ccc_tree      = NULL;
1474         const guint8 *ptime = tvb_get_ptr(tvb, 4, 8);
1475
1476         if ( tree ) {
1477                 ti = proto_tree_add_item(tree, proto_pkt_ccc, tvb, 0, 12, FALSE);
1478                 pkt_ccc_tree = proto_item_add_subtree(ti, ett_pkt_ccc);
1479
1480                 proto_tree_add_item(pkt_ccc_tree, hf_pkt_ccc_id, tvb, 0, 4, FALSE);
1481                 proto_tree_add_bytes_format(pkt_ccc_tree, hf_pkt_ccc_ts, tvb,
1482                                             4, 8, ptime, "NTP timestamp: %s", ntp_fmt_ts(ptime));
1483         }
1484
1485         dissect_rtp(tvb, pinfo, tree);
1486 }
1487
1488
1489 /* Register PacketCable CCC */
1490
1491 void
1492 proto_register_pkt_ccc(void)
1493 {
1494         static hf_register_info hf[] =
1495         {
1496                 {
1497                         &hf_pkt_ccc_id,
1498                         {
1499                                 "PacketCable CCC Identifier",
1500                                 "pkt_ccc.ccc_id",
1501                                 FT_UINT32,
1502                                 BASE_DEC,
1503                                 NULL,
1504                                 0x0,
1505                                 "CCC_ID", HFILL
1506                         }
1507                 },
1508                 {
1509                         &hf_pkt_ccc_ts,
1510                         {
1511                                 "PacketCable CCC Timestamp",
1512                                 "pkt_ccc.ts",
1513                                 FT_BYTES,
1514                                 BASE_NONE,
1515                                 NULL,
1516                                 0x0,
1517                                 "Timestamp", HFILL
1518                         }
1519                 },
1520
1521         };
1522
1523         static gint *ett[] =
1524         {
1525                 &ett_pkt_ccc,
1526         };
1527
1528         module_t *pkt_ccc_module;
1529
1530         proto_pkt_ccc = proto_register_protocol("PacketCable Call Content Connection",
1531             "PKT CCC", "pkt_ccc");
1532         proto_register_field_array(proto_pkt_ccc, hf, array_length(hf));
1533         proto_register_subtree_array(ett, array_length(ett));
1534
1535         register_dissector("pkt_ccc", dissect_pkt_ccc, proto_pkt_ccc);
1536
1537         pkt_ccc_module = prefs_register_protocol(proto_pkt_ccc, proto_reg_handoff_pkt_ccc);
1538
1539         prefs_register_uint_preference(pkt_ccc_module, "udp_port",
1540                                        "UDP port",
1541                                        "Decode packets on this UDP port as PacketCable CCC",
1542                                        10, &global_pkt_ccc_udp_port);
1543 }
1544
1545 void
1546 proto_reg_handoff_pkt_ccc(void)
1547 {
1548         /*
1549          * Register this dissector as one that can be selected by a
1550          * UDP port number.
1551          */
1552         static gboolean initialized = FALSE;
1553         static dissector_handle_t pkt_ccc_handle;
1554         static guint saved_pkt_ccc_udp_port;
1555
1556         if (!initialized) {
1557                 pkt_ccc_handle = find_dissector("pkt_ccc");
1558                 dissector_add_handle("udp.port", pkt_ccc_handle);  /* for 'decode-as' */
1559                 initialized = TRUE;
1560         } else {
1561                 if (saved_pkt_ccc_udp_port != 0) {
1562                         dissector_delete("udp.port", saved_pkt_ccc_udp_port, pkt_ccc_handle);
1563                 }
1564         }
1565
1566         if (global_pkt_ccc_udp_port != 0) {
1567                 dissector_add("udp.port", global_pkt_ccc_udp_port, pkt_ccc_handle);
1568         }
1569         saved_pkt_ccc_udp_port = global_pkt_ccc_udp_port;
1570 }
1571
1572 /* Register RTP */
1573
1574 void
1575 proto_register_rtp(void)
1576 {
1577         static hf_register_info hf[] =
1578         {
1579                 {
1580                         &hf_rtp_version,
1581                         {
1582                                 "Version",
1583                                 "rtp.version",
1584                                 FT_UINT8,
1585                                 BASE_DEC,
1586                                 VALS(rtp_version_vals),
1587                                 0xC0,
1588                                 NULL, HFILL
1589                         }
1590                 },
1591                 {
1592                         &hf_rtp_padding,
1593                         {
1594                                 "Padding",
1595                                 "rtp.padding",
1596                                 FT_BOOLEAN,
1597                                 8,
1598                                 NULL,
1599                                 0x20,
1600                                 NULL, HFILL
1601                         }
1602                 },
1603                 {
1604                         &hf_rtp_extension,
1605                         {
1606                                 "Extension",
1607                                 "rtp.ext",
1608                                 FT_BOOLEAN,
1609                                 8,
1610                                 NULL,
1611                                 0x10,
1612                                 NULL, HFILL
1613                         }
1614                 },
1615                 {
1616                         &hf_rtp_csrc_count,
1617                         {
1618                                 "Contributing source identifiers count",
1619                                 "rtp.cc",
1620                                 FT_UINT8,
1621                                 BASE_DEC,
1622                                 NULL,
1623                                 0x0F,
1624                                 NULL, HFILL
1625                         }
1626                 },
1627                 {
1628                         &hf_rtp_marker,
1629                         {
1630                                 "Marker",
1631                                 "rtp.marker",
1632                                 FT_BOOLEAN,
1633                                 8,
1634                                 NULL,
1635                                 0x80,
1636                                 NULL, HFILL
1637                         }
1638                 },
1639                 {
1640                         &hf_rtp_payload_type,
1641                         {
1642                                 "Payload type",
1643                                 "rtp.p_type",
1644                                 FT_UINT8,
1645                                 BASE_DEC,
1646                                 NULL,
1647                                 0x7F,
1648                                 NULL, HFILL
1649                         }
1650                 },
1651                 {
1652                         &hf_rtp_seq_nr,
1653                         {
1654                                 "Sequence number",
1655                                 "rtp.seq",
1656                                 FT_UINT16,
1657                                 BASE_DEC,
1658                                 NULL,
1659                                 0x0,
1660                                 NULL, HFILL
1661                         }
1662                 },
1663                 {
1664                         &hf_rtp_ext_seq_nr,
1665                         {
1666                                 "Extended sequence number",
1667                                 "rtp.extseq",
1668                                 FT_UINT32,
1669                                 BASE_DEC,
1670                                 NULL,
1671                                 0x0,
1672                                 NULL, HFILL
1673                         }
1674                 },
1675                 {
1676                         &hf_rtp_timestamp,
1677                         {
1678                                 "Timestamp",
1679                                 "rtp.timestamp",
1680                                 FT_UINT32,
1681                                 BASE_DEC,
1682                                 NULL,
1683                                 0x0,
1684                                 NULL, HFILL
1685                         }
1686                 },
1687                 {
1688                         &hf_rtp_ssrc,
1689                         {
1690                                 "Synchronization Source identifier",
1691                                 "rtp.ssrc",
1692                                 FT_UINT32,
1693                                 BASE_HEX_DEC,
1694                                 NULL,
1695                                 0x0,
1696                                 NULL, HFILL
1697                         }
1698                 },
1699                 {
1700                         &hf_rtp_prof_define,
1701                         {
1702                                 "Defined by profile",
1703                                 "rtp.ext.profile",
1704                                 FT_UINT16,
1705                                 BASE_DEC,
1706                                 NULL,
1707                                 0x0,
1708                                 NULL, HFILL
1709                         }
1710                 },
1711                 {
1712                         &hf_rtp_length,
1713                         {
1714                                 "Extension length",
1715                                 "rtp.ext.len",
1716                                 FT_UINT16,
1717                                 BASE_DEC,
1718                                 NULL,
1719                                 0x0,
1720                                 NULL, HFILL
1721                         }
1722                 },
1723                 {
1724                         &hf_rtp_csrc_items,
1725                         {
1726                                 "Contributing Source identifiers",
1727                                 "rtp.csrc.items",
1728                                 FT_NONE,
1729                                 BASE_NONE,
1730                                 NULL,
1731                                 0x0,
1732                                 NULL, HFILL
1733                         }
1734                 },
1735                 {
1736                         &hf_rtp_csrc_item,
1737                         {
1738                                 "CSRC item",
1739                                 "rtp.csrc.item",
1740                                 FT_UINT32,
1741                                 BASE_HEX_DEC,
1742                                 NULL,
1743                                 0x0,
1744                                 NULL, HFILL
1745                         }
1746                 },
1747                 {
1748                         &hf_rtp_hdr_exts,
1749                         {
1750                                 "Header extensions",
1751                                 "rtp.hdr_exts",
1752                                 FT_NONE,
1753                                 BASE_NONE,
1754                                 NULL,
1755                                 0x0,
1756                                 NULL, HFILL
1757                         }
1758                 },
1759                 {
1760                         &hf_rtp_hdr_ext,
1761                         {
1762                                 "Header extension",
1763                                 "rtp.hdr_ext",
1764                                 FT_UINT32,
1765                                 BASE_DEC,
1766                                 NULL,
1767                                 0x0,
1768                                 NULL, HFILL
1769                         }
1770                 },
1771                 {
1772                         &hf_rtp_data,
1773                         {
1774                                 "Payload",
1775                                 "rtp.payload",
1776                                 FT_BYTES,
1777                                 BASE_NONE,
1778                                 NULL,
1779                                 0x0,
1780                                 NULL, HFILL
1781                         }
1782                 },
1783                 {
1784                         &hf_rtp_padding_data,
1785                         {
1786                                 "Padding data",
1787                                 "rtp.padding.data",
1788                                 FT_BYTES,
1789                                 BASE_NONE,
1790                                 NULL,
1791                                 0x0,
1792                                 NULL, HFILL
1793                         }
1794                 },
1795                 {
1796                         &hf_rtp_padding_count,
1797                         {
1798                                 "Padding count",
1799                                 "rtp.padding.count",
1800                                 FT_UINT8,
1801                                 BASE_DEC,
1802                                 NULL,
1803                                 0x0,
1804                                 NULL, HFILL
1805                         }
1806                 },
1807                 {
1808                         &hf_rtp_setup,
1809                         {
1810                                 "Stream setup",
1811                                 "rtp.setup",
1812                                 FT_STRING,
1813                                 BASE_NONE,
1814                                 NULL,
1815                                 0x0,
1816                                 "Stream setup, method and frame number", HFILL
1817                         }
1818                 },
1819                 {
1820                         &hf_rtp_setup_frame,
1821                         {
1822                                 "Setup frame",
1823                                 "rtp.setup-frame",
1824                                 FT_FRAMENUM,
1825                                 BASE_NONE,
1826                                 NULL,
1827                                 0x0,
1828                                 "Frame that set up this stream", HFILL
1829                         }
1830                 },
1831                 {
1832                         &hf_rtp_setup_method,
1833                         {
1834                                 "Setup Method",
1835                                 "rtp.setup-method",
1836                                 FT_STRING,
1837                                 BASE_NONE,
1838                                 NULL,
1839                                 0x0,
1840                                 "Method used to set up this stream", HFILL
1841                         }
1842                 },
1843                 {
1844                         &hf_rtp_rfc2198_follow,
1845                         {
1846                                 "Follow",
1847                                 "rtp.follow",
1848                                 FT_BOOLEAN,
1849                                 8,
1850                                 TFS(&tfs_set_notset),
1851                                 0x80,
1852                                 "Next header follows", HFILL
1853                         }
1854                 },
1855                 {
1856                         &hf_rtp_rfc2198_tm_off,
1857                         {
1858                                 "Timestamp offset",
1859                                 "rtp.timestamp-offset",
1860                                 FT_UINT16,
1861                                 BASE_DEC,
1862                                 NULL,
1863                                 0xFFFC,
1864                                 NULL, HFILL
1865                         }
1866                 },
1867                 {
1868                         &hf_rtp_rfc2198_bl_len,
1869                         {
1870                                 "Block length",
1871                                 "rtp.block-length",
1872                                 FT_UINT16,
1873                                 BASE_DEC,
1874                                 NULL,
1875                                 0x03FF,
1876                                 NULL, HFILL
1877                         }
1878                 },
1879
1880                 /* reassembly stuff */
1881                 {&hf_rtp_fragments,
1882                  {"RTP Fragments", "rtp.fragments", FT_NONE, BASE_NONE, NULL, 0x0,
1883                   NULL, HFILL }
1884                 },
1885
1886                 {&hf_rtp_fragment,
1887                  {"RTP Fragment data", "rtp.fragment", FT_FRAMENUM, BASE_NONE, NULL, 0x0,
1888                   NULL, HFILL }
1889                 },
1890
1891                 {&hf_rtp_fragment_overlap,
1892                  {"Fragment overlap", "rtp.fragment.overlap", FT_BOOLEAN, BASE_NONE,
1893                   NULL, 0x0, "Fragment overlaps with other fragments", HFILL }
1894                 },
1895
1896                 {&hf_rtp_fragment_overlap_conflict,
1897                  {"Conflicting data in fragment overlap", "rtp.fragment.overlap.conflict",
1898                   FT_BOOLEAN, BASE_NONE, NULL, 0x0,
1899                   "Overlapping fragments contained conflicting data", HFILL }
1900                 },
1901
1902                 {&hf_rtp_fragment_multiple_tails,
1903                  {"Multiple tail fragments found", "rtp.fragment.multipletails",
1904                   FT_BOOLEAN, BASE_NONE, NULL, 0x0,
1905                   "Several tails were found when defragmenting the packet", HFILL }
1906                 },
1907
1908                 {&hf_rtp_fragment_too_long_fragment,
1909                  {"Fragment too long", "rtp.fragment.toolongfragment",
1910                   FT_BOOLEAN, BASE_NONE, NULL, 0x0,
1911                   "Fragment contained data past end of packet", HFILL }
1912                 },
1913
1914                 {&hf_rtp_fragment_error,
1915                  {"Defragmentation error", "rtp.fragment.error",
1916                   FT_FRAMENUM, BASE_NONE, NULL, 0x0,
1917                   "Defragmentation error due to illegal fragments", HFILL }
1918                 },
1919
1920                 {&hf_rtp_reassembled_in,
1921                  {"RTP fragment, reassembled in frame", "rtp.reassembled_in",
1922                   FT_FRAMENUM, BASE_NONE, NULL, 0x0,
1923                   "This RTP packet is reassembled in this frame", HFILL }
1924                 },
1925                 {&hf_srtp_encrypted_payload,
1926                  {"SRTP Encrypted Payload", "srtp.enc_payload",
1927                   FT_BYTES, BASE_NONE, NULL, 0x0,
1928                   NULL, HFILL }
1929                 },
1930                 {&hf_srtp_mki,
1931                  {"SRTP MKI", "srtp.mki",
1932                   FT_BYTES, BASE_NONE, NULL, 0x0,
1933                   "SRTP Master Key Index", HFILL }
1934                 },
1935                 {&hf_srtp_auth_tag,
1936                  {"SRTP Auth Tag", "srtp.auth_tag",
1937                   FT_BYTES, BASE_NONE, NULL, 0x0,
1938                   "SRTP Authentication Tag", HFILL }
1939                 }
1940
1941         };
1942
1943         static gint *ett[] =
1944         {
1945                 &ett_rtp,
1946                 &ett_csrc_list,
1947                 &ett_hdr_ext,
1948                 &ett_rtp_setup,
1949                 &ett_rtp_rfc2198,
1950                 &ett_rtp_rfc2198_hdr,
1951                 &ett_rtp_fragment,
1952                 &ett_rtp_fragments
1953         };
1954
1955         module_t *rtp_module;
1956
1957
1958         proto_rtp = proto_register_protocol("Real-Time Transport Protocol",
1959                                             "RTP", "rtp");
1960         proto_register_field_array(proto_rtp, hf, array_length(hf));
1961         proto_register_subtree_array(ett, array_length(ett));
1962
1963         register_dissector("rtp", dissect_rtp, proto_rtp);
1964         register_dissector("rtp.rfc2198", dissect_rtp_rfc2198, proto_rtp);
1965
1966         rtp_tap = register_tap("rtp");
1967
1968         rtp_pt_dissector_table = register_dissector_table("rtp.pt",
1969                                                           "RTP payload type", FT_UINT8, BASE_DEC);
1970         rtp_dyn_pt_dissector_table = register_dissector_table("rtp_dyn_payload_type",
1971                                                               "Dynamic RTP payload type", FT_STRING, BASE_NONE);
1972
1973
1974         rtp_hdr_ext_dissector_table = register_dissector_table("rtp_hdr_ext",
1975                                                                "RTP header extension", FT_STRING, BASE_NONE);
1976
1977         rtp_module = prefs_register_protocol(proto_rtp, proto_reg_handoff_rtp);
1978
1979         prefs_register_bool_preference(rtp_module, "show_setup_info",
1980                                        "Show stream setup information",
1981                                        "Where available, show which protocol and frame caused "
1982                                        "this RTP stream to be created",
1983                                        &global_rtp_show_setup_info);
1984
1985         prefs_register_bool_preference(rtp_module, "heuristic_rtp",
1986                                        "Try to decode RTP outside of conversations",
1987                                        "If call control SIP/H323/RTSP/.. messages are missing in the trace, "
1988                                        "RTP isn't decoded without this",
1989                                        &global_rtp_heur);
1990
1991         prefs_register_bool_preference(rtp_module, "desegment_rtp_streams",
1992                                        "Allow subdissector to reassemble RTP streams",
1993                                        "Whether subdissector can request RTP streams to be reassembled",
1994                                        &desegment_rtp);
1995
1996         prefs_register_enum_preference(rtp_module, "version0_type",
1997                                        "Treat RTP version 0 packets as",
1998                                        "If an RTP version 0 packet is encountered, it can be treated as "
1999                                        "an invalid or ZRTP packet, a CLASSIC-STUN packet, or a T.38 packet",
2000                                        &global_rtp_version0_type,
2001                                        rtp_version0_types, FALSE);
2002         prefs_register_uint_preference(rtp_module,
2003                                        "rfc2198_payload_type", "Payload Type for RFC2198",
2004                                        "Payload Type for RFC2198 Redundant Audio Data",
2005                                        10,
2006                                        &rtp_rfc2198_pt);
2007
2008         register_init_routine(rtp_fragment_init);
2009 }
2010
2011 void
2012 proto_reg_handoff_rtp(void)
2013 {
2014         static gboolean rtp_prefs_initialized = FALSE;
2015         static dissector_handle_t rtp_rfc2198_handle;
2016         static guint rtp_saved_rfc2198_pt;
2017
2018         if (!rtp_prefs_initialized) {
2019                 rtp_handle = find_dissector("rtp");
2020                 rtp_rfc2198_handle = find_dissector("rtp.rfc2198");
2021
2022                 dissector_add_handle("udp.port", rtp_handle);  /* for 'decode-as' */
2023                 dissector_add_string("rtp_dyn_payload_type", "red", rtp_rfc2198_handle);
2024                 heur_dissector_add( "udp", dissect_rtp_heur, proto_rtp);
2025                 heur_dissector_add("stun", dissect_rtp_heur, proto_rtp);
2026
2027                 data_handle = find_dissector("data");
2028                 classicstun_handle = find_dissector("classicstun");
2029                 classicstun_heur_handle = find_dissector("classicstun-heur");
2030                 t38_handle = find_dissector("t38");
2031                 zrtp_handle = find_dissector("zrtp");
2032
2033                 rtp_prefs_initialized = TRUE;
2034         } else {
2035                 dissector_delete("rtp.pt", rtp_saved_rfc2198_pt, rtp_rfc2198_handle);
2036         }
2037         dissector_add("rtp.pt", rtp_rfc2198_pt, rtp_rfc2198_handle);
2038         rtp_saved_rfc2198_pt = rtp_rfc2198_pt;
2039 }
2040
2041 /*
2042  * Local Variables:
2043  * c-basic-offset: 8
2044  * indent-tabs-mode: t
2045  * tab-width: 8
2046  * End:
2047  */