packet-wtp.c

   1 /* packet-wtp.c
   2  *
   3  * Routines to dissect WTP component of WAP traffic.
   4  *
   5  * $Id: packet-wtp.c,v 1.53 2003/11/05 04:23:59 guy Exp $
   6  *
   7  * Ethereal - Network traffic analyzer
   8  * By Gerald Combs <gerald@ethereal.com>
   9  * Copyright 1998 Gerald Combs
  10  *
  11  * WAP dissector based on original work by Ben Fowler
  12  * Updated by Neil Hunter <neil.hunter@energis-squared.com>
  13  * WTLS support by Alexandre P. Ferreira (Splice IP)
  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 #ifdef HAVE_CONFIG_H
  31 # include "config.h"
  32 #endif
  33
  34 #include <stdio.h>
  35 #include <stdlib.h>
  36
  37 #ifdef NEED_SNPRINTF_H
  38 # include "snprintf.h"
  39 #endif
  40
  41 #include <string.h>
  42 #include <glib.h>
  43 #include <epan/packet.h>
  44 #include "reassemble.h"
  45 #include "packet-wap.h"
  46 #include "packet-wtp.h"
  47 #include "packet-wsp.h"
  48
  49 static const true_false_string continue_truth = {
  50     "TPI Present" ,
  51     "No TPI"
  52 };
  53
  54 static const true_false_string RID_truth = {
  55     "Re-Transmission",
  56     "First transmission"
  57 };
  58
  59 static const true_false_string TIDNew_truth = {
  60     "TID is new" ,
  61     "TID is valid"
  62 };
  63
  64 static const true_false_string tid_response_truth = {
  65     "Response" ,
  66     "Original"
  67 };
  68
  69 static const true_false_string UP_truth = {
  70     "User Acknowledgement required" ,
  71     "User Acknowledgement optional"
  72 };
  73
  74 static const true_false_string TVETOK_truth = {
  75     "True",
  76     "False"
  77 };
  78
  79 static const value_string vals_pdu_type[] = {
  80     { 0, "Not Allowed" },
  81     { 1, "Invoke" },
  82     { 2, "Result" },
  83     { 3, "Ack" },
  84     { 4, "Abort" },
  85     { 5, "Segmented Invoke" },
  86     { 6, "Segmented Result" },
  87     { 7, "Negative Ack" },
  88     { 0, NULL }
  89 };
  90
  91 static const value_string vals_transaction_trailer[] = {
  92     { 0, "Not last packet" },
  93     { 1, "Last packet of message" },
  94     { 2, "Last packet of group" },
  95     { 3, "Re-assembly not supported" },
  96     { 0, NULL }
  97 };
  98
  99 static const value_string vals_version[] = {
 100     { 0, "Current" },
 101     { 1, "Undefined" },
 102     { 2, "Undefined" },
 103     { 3, "Undefined" },
 104     { 0, NULL }
 105 };
 106
 107 static const value_string vals_abort_type[] = {
 108     { 0, "Provider" },
 109     { 1, "User (WSP)" },
 110     { 0, NULL }
 111 };
 112
 113 static const value_string vals_abort_reason_provider[] = {
 114     { 0x00, "Unknown" },
 115     { 0x01, "Protocol Error" },
 116     { 0x02, "Invalid TID" },
 117     { 0x03, "Not Implemented Class 2" },
 118     { 0x04, "Not Implemented SAR" },
 119     { 0x05, "Not Implemented User Acknowledgement" },
 120     { 0x06, "WTP Version Zero" },
 121     { 0x07, "Capacity Temporarily Exceeded" },
 122     { 0x08, "No Response" },
 123     { 0x09, "Message Too Large" },
 124     { 0x00, NULL }
 125 };
 126
 127 static const value_string vals_transaction_classes[] = {
 128     { 0x00, "Unreliable Invoke without Result" },
 129     { 0x01, "Reliable Invoke without Result" },
 130     { 0x02, "Reliable Invoke with Reliable Result" },
 131     { 0x00, NULL }
 132 };
 133
 134 static const value_string vals_tpi_type[] = {
 135     { 0x00, "Error" },
 136     { 0x01, "Info" },
 137     { 0x02, "Option" },
 138     { 0x03, "Packet sequence number" },
 139     { 0x04, "SDU boundary" },
 140     { 0x05, "Frame boundary" },
 141     { 0x00, NULL }
 142 };
 143
 144 static const value_string vals_tpi_opt[] = {
 145     { 0x01, "Maximum receive unit" },
 146     { 0x02, "Total message size" },
 147     { 0x03, "Delay transmission timer" },
 148     { 0x04, "Maximum group" },
 149     { 0x05, "Current TID" },
 150     { 0x06, "No cached TID" },
 151     { 0x00, NULL }
 152 };
 153
 154 /* File scoped variables for the protocol and registered fields */
 155 static int proto_wtp                            = HF_EMPTY;
 156
 157 /* These fields used by fixed part of header */
 158 static int hf_wtp_header_sub_pdu_size           = HF_EMPTY;
 159 static int hf_wtp_header_flag_continue          = HF_EMPTY;
 160 static int hf_wtp_header_pdu_type               = HF_EMPTY;
 161 static int hf_wtp_header_flag_Trailer           = HF_EMPTY;
 162 static int hf_wtp_header_flag_RID               = HF_EMPTY;
 163 static int hf_wtp_header_flag_TID               = HF_EMPTY;
 164 static int hf_wtp_header_flag_TID_response      = HF_EMPTY;
 165
 166 /* These fields used by Invoke packets */
 167 static int hf_wtp_header_Inv_version            = HF_EMPTY;
 168 static int hf_wtp_header_Inv_flag_TIDNew        = HF_EMPTY;
 169 static int hf_wtp_header_Inv_flag_UP            = HF_EMPTY;
 170 static int hf_wtp_header_Inv_Reserved           = HF_EMPTY;
 171 static int hf_wtp_header_Inv_TransactionClass   = HF_EMPTY;
 172
 173
 174 static int hf_wtp_header_variable_part          = HF_EMPTY;
 175 static int hf_wtp_data                          = HF_EMPTY;
 176
 177 static int hf_wtp_tpi_type                      = HF_EMPTY;
 178 static int hf_wtp_tpi_psn                       = HF_EMPTY;
 179 static int hf_wtp_tpi_opt                       = HF_EMPTY;
 180 static int hf_wtp_tpi_optval                    = HF_EMPTY;
 181 static int hf_wtp_tpi_info                      = HF_EMPTY;
 182
 183 static int hf_wtp_header_Ack_flag_TVETOK        = HF_EMPTY;
 184 static int hf_wtp_header_Abort_type             = HF_EMPTY;
 185 static int hf_wtp_header_Abort_reason_provider  = HF_EMPTY;
 186 static int hf_wtp_header_Abort_reason_user      = HF_EMPTY;
 187 static int hf_wtp_header_sequence_number        = HF_EMPTY;
 188 static int hf_wtp_header_missing_packets        = HF_EMPTY;
 189
 190 /* These fields used when reassembling WTP fragments */
 191 static int hf_wtp_fragments                     = HF_EMPTY;
 192 static int hf_wtp_fragment                      = HF_EMPTY;
 193 static int hf_wtp_fragment_overlap              = HF_EMPTY;
 194 static int hf_wtp_fragment_overlap_conflict     = HF_EMPTY;
 195 static int hf_wtp_fragment_multiple_tails       = HF_EMPTY;
 196 static int hf_wtp_fragment_too_long_fragment    = HF_EMPTY;
 197 static int hf_wtp_fragment_error                = HF_EMPTY;
 198
 199 /* Initialize the subtree pointers */
 200 static gint ett_wtp                             = ETT_EMPTY;
 201 static gint ett_wtp_sub_pdu_tree        = ETT_EMPTY;
 202 static gint ett_header                          = ETT_EMPTY;
 203 static gint ett_tpilist                         = ETT_EMPTY;
 204 static gint ett_wsp_fragments                   = ETT_EMPTY;
 205 static gint ett_wtp_fragment                    = ETT_EMPTY;
 206
 207 static const fragment_items wtp_frag_items = {
 208     &ett_wtp_fragment,
 209     &ett_wsp_fragments,
 210     &hf_wtp_fragments,
 211     &hf_wtp_fragment,
 212     &hf_wtp_fragment_overlap,
 213     &hf_wtp_fragment_overlap_conflict,
 214     &hf_wtp_fragment_multiple_tails,
 215     &hf_wtp_fragment_too_long_fragment,
 216     &hf_wtp_fragment_error,
 217     NULL,
 218     "fragments"
 219 };
 220
 221 /* Handle for WSP dissector */
 222 static dissector_handle_t wsp_handle;
 223
 224 /*
 225  * reassembly of WSP
 226  */
 227 static GHashTable       *wtp_fragment_table = NULL;
 228
 229 static void
 230 wtp_defragment_init(void)
 231 {
 232     fragment_table_init(&wtp_fragment_table);
 233 }
 234
 235 /*
 236  * Extract some bitfields
 237  */
 238 #define pdu_type(octet)                 (((octet) >> 3) & 0x0F) /* Note pdu type must not be 0x00 */
 239 #define transaction_class(octet)        ((octet) & 0x03)        /* ......XX */
 240 #define transmission_trailer(octet)     (((octet) >> 1) & 0x01) /* ......X. */
 241
 242 static char retransmission_indicator(unsigned char octet)
 243 {
 244     switch (pdu_type(octet)) {
 245         case INVOKE:
 246         case RESULT:
 247         case ACK:
 248         case SEGMENTED_INVOKE:
 249         case SEGMENTED_RESULT:
 250         case NEGATIVE_ACK:
 251             return octet & 0x01;        /* .......X */
 252         default:
 253             return 0;
 254     }
 255 }
 256
 257 /*
 258  * dissect a TPI
 259  */
 260 static void
 261 wtp_handle_tpi(proto_tree *tree, tvbuff_t *tvb)
 262 {
 263     int                  offset = 0;
 264     unsigned char        tByte;
 265     unsigned char        tType;
 266     unsigned char        tLen;
 267     proto_item          *subTree = NULL;
 268
 269     tByte = tvb_get_guint8(tvb, offset++);
 270     tType = (tByte & 0x78) >> 3;
 271     if (tByte & 0x04)                           /* Long TPI     */
 272         tLen = tvb_get_guint8(tvb, offset++);
 273     else
 274         tLen = tByte & 0x03;
 275     subTree = proto_tree_add_uint(tree, hf_wtp_tpi_type,
 276                                   tvb, 0, tvb_length(tvb), tType);
 277     proto_item_add_subtree(subTree, ett_tpilist);
 278     switch (tType) {
 279         case 0x00:                      /* Error*/
 280             /* \todo    */
 281             break;
 282         case 0x01:                      /* Info */
 283             /* Beware, untested case here       */
 284             proto_tree_add_item(subTree, hf_wtp_tpi_info,
 285                                 tvb, offset, tLen, bo_little_endian);
 286             break;
 287         case 0x02:                      /* Option       */
 288             proto_tree_add_item(subTree, hf_wtp_tpi_opt,
 289                                 tvb, offset++, 1, bo_little_endian);
 290             proto_tree_add_item(subTree, hf_wtp_tpi_optval,
 291                                 tvb, offset, tLen - 1, bo_little_endian);
 292             break;
 293         case 0x03:                      /* PSN  */
 294             proto_tree_add_item(subTree, hf_wtp_tpi_psn,
 295                                 tvb, offset, 1, bo_little_endian);
 296             break;
 297         case 0x04:                      /* SDU boundary */
 298             /* \todo    */
 299             break;
 300         case 0x05:                      /* Frame boundary       */
 301             /* \todo    */
 302             break;
 303         default:
 304             break;
 305     }
 306 }
 307
 308 /* Code to actually dissect the packets */
 309 static void
 310 dissect_wtp_common(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 311 {
 312     static GString *szInfo = NULL;
 313     int         offCur          = 0; /* current offset from start of WTP data */
 314
 315     unsigned char  b0;
 316
 317     /* continuation flag */
 318     unsigned char       fCon;                   /* Continue flag        */
 319     unsigned char       fRID;                   /* Re-transmission indicator*/
 320     unsigned char       fTTR = '\0';            /* Transmission trailer */
 321     guint               cbHeader        = 0;    /* Fixed header length  */
 322     guint               vHeader         = 0;    /* Variable header length*/
 323     int                 abortType       = 0;
 324
 325     /* Set up structures we'll need to add the protocol subtree and manage it */
 326     proto_item          *ti;
 327     proto_tree          *wtp_tree = NULL;
 328
 329     char                pdut;
 330     char                clsTransaction  = ' ';
 331     int                 numMissing = 0;         /* Number of missing packets in a negative ack */
 332     int                 i;
 333     tvbuff_t            *wsp_tvb = NULL;
 334     fragment_data       *fd_head = NULL;
 335     guint8              psn = 0;                /* Packet sequence number*/
 336     guint16             TID = 0;                /* Transaction-Id       */
 337
 338     if (szInfo == NULL)
 339         szInfo = g_string_sized_new(32);
 340
 341     b0 = tvb_get_guint8 (tvb, offCur + 0);
 342     /* Discover Concatenated PDUs */
 343     if (b0 == 0) {
 344         guint   c_fieldlen = 0;         /* Length of length-field       */
 345         guint   c_pdulen = 0;           /* Length of conc. PDU  */
 346
 347         if (tree) {
 348             ti = proto_tree_add_item(tree, proto_wtp,
 349                                     tvb, offCur, 1, bo_little_endian);
 350             wtp_tree = proto_item_add_subtree(ti, ett_wtp_sub_pdu_tree);
 351         }
 352         offCur = 1;
 353         i = 1;
 354         while (offCur < (int) tvb_reported_length(tvb)) {
 355             b0 = tvb_get_guint8(tvb, offCur + 0);
 356             if (b0 & 0x80) {
 357                 c_fieldlen = 2;
 358                 c_pdulen = ((b0 & 0x7f) << 8) | tvb_get_guint8(tvb, offCur + 1);
 359             } else {
 360                 c_fieldlen = 1;
 361                 c_pdulen = b0;
 362             }
 363             if (tree) {
 364                 proto_tree_add_uint(wtp_tree, hf_wtp_header_sub_pdu_size,
 365                                     tvb, offCur, c_fieldlen, c_pdulen);
 366             }
 367             if (i > 1 && check_col(pinfo->cinfo, COL_INFO)) {
 368                 col_append_str(pinfo->cinfo, COL_INFO, ", ");
 369             }
 370             wsp_tvb = tvb_new_subset(tvb, offCur + c_fieldlen, c_pdulen, c_pdulen);
 371             dissect_wtp_common(wsp_tvb, pinfo, wtp_tree);
 372             offCur += c_fieldlen + c_pdulen;
 373             i++;
 374         }
 375         return;
 376     }
 377     fCon = b0 & 0x80;
 378     fRID = retransmission_indicator(b0);
 379     pdut = pdu_type(b0);
 380
 381     /* Develop the string to put in the Info column */
 382     g_string_sprintf(szInfo, "WTP %s",
 383                     val_to_str(pdut, vals_pdu_type, "Unknown PDU type 0x%x"));
 384
 385     switch (pdut) {
 386         case INVOKE:
 387             fTTR = transmission_trailer(b0);
 388             TID = tvb_get_ntohs(tvb, offCur + 1);
 389             psn = 0;
 390             clsTransaction = transaction_class(tvb_get_guint8(tvb, offCur + 3));
 391             g_string_sprintfa(szInfo, " Class %d", clsTransaction);
 392             cbHeader = 4;
 393             break;
 394
 395         case SEGMENTED_INVOKE:
 396         case SEGMENTED_RESULT:
 397             fTTR = transmission_trailer(b0);
 398             TID = tvb_get_ntohs(tvb, offCur + 1);
 399             psn = tvb_get_guint8(tvb, offCur + 3);
 400             cbHeader = 4;
 401             break;
 402
 403         case ABORT:
 404             cbHeader = 4;
 405             break;
 406
 407         case RESULT:
 408             fTTR = transmission_trailer(b0);
 409             TID = tvb_get_ntohs(tvb, offCur + 1);
 410             psn = 0;
 411             cbHeader = 3;
 412             break;
 413
 414         case ACK:
 415             cbHeader = 3;
 416             break;
 417
 418         case NEGATIVE_ACK:
 419             /* Variable number of missing packets */
 420             numMissing = tvb_get_guint8(tvb, offCur + 3);
 421             cbHeader = numMissing + 4;
 422             break;
 423
 424         default:
 425             break;
 426     };
 427     if (fRID) {
 428         g_string_append( szInfo, " R" );
 429     };
 430     if (fCon) {                         /* Scan variable part (TPI's),  */
 431                                         /* determine length of it       */
 432         unsigned char   tCon;
 433         unsigned char   tByte;
 434
 435         do {
 436             tByte = tvb_get_guint8(tvb, offCur + cbHeader + vHeader);
 437             tCon = tByte & 0x80;
 438             if (tByte & 0x04)   /* Long format  */
 439                 vHeader = vHeader + tvb_get_guint8(tvb,
 440                                         offCur + cbHeader + vHeader + 1) + 2;
 441             else
 442                 vHeader = vHeader + (tByte & 0x03) + 1;
 443         } while (tCon);
 444     }
 445
 446 #ifdef DEBUG
 447     fprintf( stderr, "dissect_wtp: cbHeader = %d\n", cbHeader );
 448 #endif
 449
 450     /* Only update "Info" column when no data in this PDU will
 451      * be handed off to a subsequent dissector.
 452      */
 453     if (check_col(pinfo->cinfo, COL_INFO) &&
 454         ((tvb_length_remaining(tvb, offCur + cbHeader + vHeader) <= 0) ||
 455          (pdut == ACK) || (pdut==NEGATIVE_ACK) || (pdut==ABORT)) ) {
 456 #ifdef DEBUG
 457         fprintf(stderr, "dissect_wtp: (6) About to set info_col header to %s\n", szInfo->str);
 458 #endif
 459         col_append_str(pinfo->cinfo, COL_INFO, szInfo->str);
 460     };
 461     /* In the interest of speed, if "tree" is NULL, don't do any work not
 462        necessary to generate protocol tree items. */
 463     if (tree) {
 464 #ifdef DEBUG
 465         fprintf(stderr, "dissect_wtp: cbHeader = %d\n", cbHeader);
 466 #endif
 467         ti = proto_tree_add_item(tree, proto_wtp, tvb, offCur, cbHeader + vHeader, bo_little_endian);
 468 #ifdef DEBUG
 469         fprintf(stderr, "dissect_wtp: (7) Returned from proto_tree_add_item\n");
 470 #endif
 471         wtp_tree = proto_item_add_subtree(ti, ett_wtp);
 472
 473 /* Code to process the packet goes here */
 474 #ifdef DEBUG
 475         fprintf(stderr, "dissect_wtp: cbHeader = %d\n", cbHeader);
 476         fprintf(stderr, "dissect_wtp: offCur = %d\n", offCur);
 477 #endif
 478         /* Add common items: only CON and PDU Type */
 479         proto_tree_add_item(
 480                         wtp_tree,                       /* tree */
 481                         hf_wtp_header_flag_continue,    /* id */
 482                         tvb,
 483                         offCur,                         /* start of highlight */
 484                         1,                              /* length of highlight*/
 485                         b0                              /* value */
 486              );
 487         proto_tree_add_item(wtp_tree, hf_wtp_header_pdu_type, tvb, offCur, 1, bo_little_endian);
 488
 489         switch(pdut) {
 490             case INVOKE:
 491                 proto_tree_add_item(wtp_tree, hf_wtp_header_flag_Trailer, tvb, offCur, 1, bo_little_endian);
 492                 proto_tree_add_item(wtp_tree, hf_wtp_header_flag_RID, tvb, offCur, 1, bo_little_endian);
 493                 proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID_response, tvb, offCur + 1, 2, bo_big_endian);
 494                 proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID, tvb, offCur + 1, 2, bo_big_endian);
 495
 496                 proto_tree_add_item(wtp_tree, hf_wtp_header_Inv_version , tvb, offCur + 3, 1, bo_little_endian);
 497                 proto_tree_add_item(wtp_tree, hf_wtp_header_Inv_flag_TIDNew, tvb, offCur + 3, 1, bo_little_endian);
 498                 proto_tree_add_item(wtp_tree, hf_wtp_header_Inv_flag_UP, tvb, offCur + 3, 1, bo_little_endian);
 499                 proto_tree_add_item(wtp_tree, hf_wtp_header_Inv_Reserved, tvb, offCur + 3, 1, bo_little_endian);
 500                 proto_tree_add_item(wtp_tree, hf_wtp_header_Inv_TransactionClass, tvb, offCur + 3, 1, bo_little_endian);
 501                 break;
 502
 503             case RESULT:
 504                 proto_tree_add_item(wtp_tree, hf_wtp_header_flag_Trailer, tvb, offCur, 1, bo_little_endian);
 505                 proto_tree_add_item(wtp_tree, hf_wtp_header_flag_RID, tvb, offCur, 1, bo_little_endian);
 506                 proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID_response, tvb, offCur + 1, 2, bo_big_endian);
 507                 proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID, tvb, offCur + 1, 2, bo_big_endian);
 508                 break;
 509
 510             case ACK:
 511                 proto_tree_add_item(wtp_tree, hf_wtp_header_Ack_flag_TVETOK, tvb, offCur, 1, bo_big_endian);
 512
 513                 proto_tree_add_item(wtp_tree, hf_wtp_header_flag_RID, tvb, offCur, 1, bo_little_endian);
 514                 proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID_response, tvb, offCur + 1, 2, bo_big_endian);
 515                 proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID, tvb, offCur + 1, 2, bo_big_endian);
 516                 break;
 517
 518             case ABORT:
 519                 abortType = tvb_get_guint8 (tvb, offCur) & 0x07;
 520                 proto_tree_add_item(wtp_tree, hf_wtp_header_Abort_type , tvb, offCur , 1, bo_little_endian);
 521                 proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID_response, tvb, offCur + 1, 2, bo_big_endian);
 522                 proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID, tvb, offCur + 1, 2, bo_big_endian);
 523
 524                 if (abortType == PROVIDER)
 525                 {
 526                     proto_tree_add_item( wtp_tree, hf_wtp_header_Abort_reason_provider , tvb, offCur + 3 , 1, bo_little_endian);
 527                 }
 528                 else if (abortType == USER)
 529                 {
 530                     proto_tree_add_item(wtp_tree, hf_wtp_header_Abort_reason_user , tvb, offCur + 3 , 1, bo_little_endian);
 531                 }
 532                 break;
 533
 534             case SEGMENTED_INVOKE:
 535                 proto_tree_add_item(wtp_tree, hf_wtp_header_flag_Trailer, tvb, offCur, 1, bo_little_endian);
 536                 proto_tree_add_item(wtp_tree, hf_wtp_header_flag_RID, tvb, offCur, 1, bo_little_endian);
 537                 proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID_response, tvb, offCur + 1, 2, bo_big_endian);
 538                 proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID, tvb, offCur + 1, 2, bo_big_endian);
 539
 540                 proto_tree_add_item(wtp_tree, hf_wtp_header_sequence_number , tvb, offCur + 3, 1, bo_little_endian);
 541                 break;
 542
 543             case SEGMENTED_RESULT:
 544                 proto_tree_add_item(wtp_tree, hf_wtp_header_flag_Trailer, tvb, offCur, 1, bo_little_endian);
 545                 proto_tree_add_item(wtp_tree, hf_wtp_header_flag_RID, tvb, offCur, 1, bo_little_endian);
 546                 proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID_response, tvb, offCur + 1, 2, bo_big_endian);
 547                 proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID, tvb, offCur + 1, 2, bo_big_endian);
 548
 549                 proto_tree_add_item(wtp_tree, hf_wtp_header_sequence_number , tvb, offCur + 3, 1, bo_little_endian);
 550                 break;
 551
 552             case NEGATIVE_ACK:
 553                 proto_tree_add_item(wtp_tree, hf_wtp_header_flag_RID, tvb, offCur, 1, bo_little_endian);
 554                 proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID_response, tvb, offCur + 1, 2, bo_big_endian);
 555                 proto_tree_add_item(wtp_tree, hf_wtp_header_flag_TID, tvb, offCur + 1, 2, bo_big_endian);
 556
 557                 proto_tree_add_item(wtp_tree, hf_wtp_header_missing_packets , tvb, offCur + 3, 1, bo_little_endian);
 558                 /* Iterate through missing packets */
 559                 for (i = 0; i < numMissing; i++)
 560                 {
 561                     proto_tree_add_item(wtp_tree, hf_wtp_header_sequence_number, tvb, offCur + 4 + i, 1, bo_little_endian);
 562                 }
 563                 break;
 564
 565             default:
 566                 break;
 567         };
 568         if (fCon) {                     /* Now, analyze variable part   */
 569             unsigned char        tCon;
 570             unsigned char        tByte;
 571             unsigned char        tpiLen;
 572             tvbuff_t            *tmp_tvb;
 573
 574             vHeader = 0;                /* Start scan all over  */
 575
 576             do {
 577                 tByte = tvb_get_guint8(tvb, offCur + cbHeader + vHeader);
 578                 tCon = tByte & 0x80;
 579                 if (tByte & 0x04)       /* Long TPI     */
 580                     tpiLen = 2 + tvb_get_guint8(tvb,
 581                                             offCur + cbHeader + vHeader + 1);
 582                 else
 583                     tpiLen = 1 + (tByte & 0x03);
 584                 tmp_tvb = tvb_new_subset(tvb, offCur + cbHeader + vHeader,
 585                                         tpiLen, tpiLen);
 586                 wtp_handle_tpi(wtp_tree, tmp_tvb);
 587                 vHeader += tpiLen;
 588             } while (tCon);
 589         } else {
 590                 /* There is no variable part */
 591         }       /* End of variable part of header */
 592     } else {
 593 #ifdef DEBUG
 594         fprintf(stderr, "dissect_wtp: (4) tree was %p\n", tree);
 595 #endif
 596     }
 597     /*
 598      * Any remaining data ought to be WSP data (if not WTP ACK, NACK
 599      * or ABORT pdu), so hand off (defragmented) to the WSP dissector.
 600      * Note that the last packet of a fragmented WTP message needn't
 601      * contain any data, so we allow payloadless packets to be
 602      * reassembled.  (XXX - does the reassembly code handle this
 603      * for packets other than the last packet?)
 604      */
 605     if ((tvb_reported_length_remaining(tvb, offCur + cbHeader + vHeader) >= 0) &&
 606         ! ((pdut==ACK) || (pdut==NEGATIVE_ACK) || (pdut==ABORT)))
 607     {
 608         int     dataOffset = offCur + cbHeader + vHeader;
 609         gint    dataLen = tvb_reported_length_remaining(tvb, dataOffset);
 610         gboolean save_fragmented;
 611
 612         if (((pdut == SEGMENTED_INVOKE) || (pdut == SEGMENTED_RESULT) ||
 613             (((pdut == INVOKE) || (pdut == RESULT)) && (!fTTR))) &&
 614             tvb_bytes_exist(tvb, dataOffset, dataLen))
 615         {                                       /* 1st part of segment  */
 616             save_fragmented = pinfo->fragmented;
 617             pinfo->fragmented = TRUE;
 618             fd_head = fragment_add_seq(tvb, dataOffset, pinfo, TID,
 619                             wtp_fragment_table, psn, dataLen, !fTTR);
 620             if (fd_head != NULL)                /* Reassembled  */
 621             {
 622                 /* Reassembly is complete; show the reassembled PDU */
 623                 wsp_tvb = tvb_new_real_data(fd_head->data,
 624                                             fd_head->len,
 625                                             fd_head->len);
 626                 tvb_set_child_real_data_tvbuff(tvb, wsp_tvb);
 627                 add_new_data_source(pinfo, wsp_tvb,
 628                                         "Reassembled WTP");
 629                 pinfo->fragmented = FALSE;
 630
 631                 /* show all fragments */
 632                 show_fragment_seq_tree(fd_head, &wtp_frag_items,
 633                                         wtp_tree, pinfo, wsp_tvb);
 634
 635                 call_dissector(wsp_handle, wsp_tvb, pinfo, tree);
 636             }
 637             else
 638             {
 639                 /* Reassembly isn't complete; just show the fragment */
 640                 if (check_col(pinfo->cinfo, COL_INFO))          /* Won't call WSP so display */
 641                     col_append_str(pinfo->cinfo, COL_INFO, szInfo->str);
 642                 if (tree != NULL)
 643                     proto_tree_add_text(wtp_tree, tvb, dataOffset, -1, "Payload");
 644             }
 645             pinfo->fragmented = save_fragmented;
 646         }
 647         else
 648         {
 649             /*
 650              * Normal packet, or not all the fragment data is available;
 651              * call next dissector, unless this is a segment of a
 652              * segmented invoke or result and isn't the first segment.
 653              */
 654             if ((pdut == SEGMENTED_INVOKE || pdut == SEGMENTED_RESULT) &&
 655                         psn != 0) {
 656                 /*
 657                  * This is a segmented invoke or result, and not the first
 658                  * segment; just show it as a segmented invoke or result,
 659                  * don't try to dissect its payload.
 660                  */
 661                 if (check_col(pinfo->cinfo, COL_INFO))
 662                     col_add_fstr(pinfo->cinfo, COL_INFO,
 663                                  "WTP %s (%u)",
 664                                  (pdut == SEGMENTED_INVOKE ?
 665                                   "Segmented Invoke" : "Segmented Result"),
 666                                  psn);
 667                 if (tree != NULL)
 668                     proto_tree_add_text(wtp_tree, tvb, dataOffset, -1, "Payload");
 669             } else {
 670                 wsp_tvb = tvb_new_subset(tvb, dataOffset, -1, -1);
 671                 call_dissector(wsp_handle, wsp_tvb, pinfo, tree);
 672             }
 673         }
 674     }
 675 }
 676
 677 /*
 678  * Called directly from UDP.
 679  * Put "WTP+WSP" into the "Protocol" column.
 680  */
 681 static void
 682 dissect_wtp_fromudp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 683 {
 684     if (check_col(pinfo->cinfo, COL_PROTOCOL))
 685         col_set_str(pinfo->cinfo, COL_PROTOCOL, "WTP+WSP" );
 686     if (check_col(pinfo->cinfo, COL_INFO))
 687         col_clear(pinfo->cinfo, COL_INFO);
 688
 689     dissect_wtp_common(tvb, pinfo, tree);
 690 }
 691
 692 /*
 693  * Called from a higher-level WAP dissector, presumably WTLS.
 694  * Put "WTLS+WSP+WTP" to the "Protocol" column.
 695  *
 696  * XXX - is this supposed to be called from WTLS?  If so, we're not
 697  * calling it....
 698  *
 699  * XXX - can this be called from any other dissector?
 700  */
 701 static void
 702 dissect_wtp_fromwap(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 703 {
 704     if (check_col(pinfo->cinfo, COL_PROTOCOL))
 705         col_set_str(pinfo->cinfo, COL_PROTOCOL, "WTLS+WTP+WSP" );
 706     if (check_col(pinfo->cinfo, COL_INFO))
 707         col_clear(pinfo->cinfo, COL_INFO);
 708
 709     dissect_wtp_common(tvb, pinfo, tree);
 710 }
 711
 712 /* Register the protocol with Ethereal */
 713 void
 714 proto_register_wtp(void)
 715 {
 716
 717     /* Setup list of header fields */
 718     static hf_register_info hf[] = {
 719         { &hf_wtp_header_sub_pdu_size,
 720             {   "Sub PDU size",
 721                 "wtp.sub_pdu_size",
 722                 FT_UINT16, BASE_DEC, NULL, 0x0,
 723                 "Size of Sub-PDU (bytes)", HFILL
 724             }
 725         },
 726         { &hf_wtp_header_flag_continue,
 727             {   "Continue Flag",
 728                 "wtp.continue_flag",
 729                 FT_BOOLEAN, 8, TFS( &continue_truth ), 0x80,
 730                 "Continue Flag", HFILL
 731             }
 732         },
 733         { &hf_wtp_header_pdu_type,
 734             {   "PDU Type",
 735                 "wtp.pdu_type",
 736                 FT_UINT8, BASE_HEX, VALS( vals_pdu_type ), 0x78,
 737                 "PDU Type", HFILL
 738             }
 739         },
 740         { &hf_wtp_header_flag_Trailer,
 741             {   "Trailer Flags",
 742                 "wtp.trailer_flags",
 743                 FT_UINT8, BASE_HEX, VALS( vals_transaction_trailer ), 0x06,
 744                 "Trailer Flags", HFILL
 745             }
 746         },
 747         { &hf_wtp_header_flag_RID,
 748             {   "Re-transmission Indicator",
 749                 "wtp.RID",
 750                 FT_BOOLEAN, 8, TFS( &RID_truth ), 0x01,
 751                 "Re-transmission Indicator", HFILL
 752             }
 753         },
 754         { &hf_wtp_header_flag_TID_response,
 755             {   "TID Response",
 756                 "wtp.TID.response",
 757                 FT_BOOLEAN, 16, TFS( &tid_response_truth ), 0x8000,
 758                 "TID Response", HFILL
 759             }
 760         },
 761         { &hf_wtp_header_flag_TID,
 762             {   "Transaction ID",
 763                 "wtp.TID",
 764                 FT_UINT16, BASE_HEX, NULL, 0x7FFF,
 765                 "Transaction ID", HFILL
 766             }
 767         },
 768         { &hf_wtp_header_Inv_version,
 769             {   "Version",
 770                 "wtp.header.version",
 771                 FT_UINT8, BASE_HEX, VALS( vals_version ), 0xC0,
 772                 "Version", HFILL
 773             }
 774         },
 775         { &hf_wtp_header_Inv_flag_TIDNew,
 776             {   "TIDNew",
 777                 "wtp.header.TIDNew",
 778                 FT_BOOLEAN, 8, TFS( &TIDNew_truth ), 0x20,
 779                 "TIDNew", HFILL
 780             }
 781         },
 782         { &hf_wtp_header_Inv_flag_UP,
 783             {   "U/P flag",
 784                 "wtp.header.UP",
 785                 FT_BOOLEAN, 8, TFS( &UP_truth ), 0x10,
 786                 "U/P Flag", HFILL
 787             }
 788         },
 789         { &hf_wtp_header_Inv_Reserved,
 790             {   "Reserved",
 791                 "wtp.inv.reserved",
 792                 FT_UINT8, BASE_HEX, NULL, 0x0C,
 793                 "Reserved", HFILL
 794             }
 795         },
 796         { &hf_wtp_header_Inv_TransactionClass,
 797             {   "Transaction Class",
 798                 "wtp.inv.transaction_class",
 799                 FT_UINT8, BASE_HEX, VALS( vals_transaction_classes ), 0x03,
 800                 "Transaction Class", HFILL
 801             }
 802         },
 803         { &hf_wtp_header_Ack_flag_TVETOK,
 804             {   "Tve/Tok flag",
 805                 "wtp.ack.tvetok",
 806                 FT_BOOLEAN, 8, TFS( &TVETOK_truth ), 0x04,
 807                 "Tve/Tok flag", HFILL
 808             }
 809         },
 810         { &hf_wtp_header_Abort_type,
 811             {   "Abort Type",
 812                 "wtp.abort.type",
 813                 FT_UINT8, BASE_HEX, VALS ( vals_abort_type ), 0x07,
 814                 "Abort Type", HFILL
 815             }
 816         },
 817         { &hf_wtp_header_Abort_reason_provider,
 818             {   "Abort Reason",
 819                 "wtp.abort.reason.provider",
 820                 FT_UINT8, BASE_HEX, VALS ( vals_abort_reason_provider ), 0x00,
 821                 "Abort Reason", HFILL
 822             }
 823         },
 824         /* Assume WSP is the user and use its reason codes */
 825         { &hf_wtp_header_Abort_reason_user,
 826             {   "Abort Reason",
 827                 "wtp.abort.reason.user",
 828                 FT_UINT8, BASE_HEX, VALS ( vals_wsp_reason_codes ), 0x00,
 829                 "Abort Reason", HFILL
 830             }
 831         },
 832         { &hf_wtp_header_sequence_number,
 833             {   "Packet Sequence Number",
 834                 "wtp.header.sequence",
 835                 FT_UINT8, BASE_DEC, NULL, 0x00,
 836                 "Packet Sequence Number", HFILL
 837             }
 838         },
 839         { &hf_wtp_header_missing_packets,
 840             {   "Missing Packets",
 841                 "wtp.header.missing_packets",
 842                 FT_UINT8, BASE_DEC, NULL, 0x00,
 843                 "Missing Packets", HFILL
 844             }
 845         },
 846         { &hf_wtp_header_variable_part,
 847             {   "Header: Variable part",
 848                 "wtp.header_variable_part",
 849                 FT_BYTES, BASE_HEX, NULL, 0x0,
 850                 "Variable part of the header", HFILL
 851             }
 852         },
 853         { &hf_wtp_data,
 854             {   "Data",
 855                 "wtp.header_data",
 856                 FT_BYTES, BASE_HEX, NULL, 0x0,
 857                 "Data", HFILL
 858             }
 859         },
 860         { &hf_wtp_tpi_type,
 861             {   "TPI",
 862                 "wtp.tpi",
 863                 FT_UINT8, BASE_HEX, VALS(vals_tpi_type), 0x00,
 864                 "Identification of the Transport Information Item", HFILL
 865             }
 866         },
 867         { &hf_wtp_tpi_psn,
 868             {   "Packet sequence number",
 869                 "wtp.tpi.psn",
 870                 FT_UINT8, BASE_DEC, NULL, 0x00,
 871                 "Sequence number of this packet", HFILL
 872             }
 873         },
 874         { &hf_wtp_tpi_opt,
 875             {   "Option",
 876                 "wtp.tpi.opt",
 877                 FT_UINT8, BASE_HEX, VALS(vals_tpi_opt), 0x00,
 878                 "The given option for this TPI", HFILL
 879             }
 880         },
 881         { &hf_wtp_tpi_optval,
 882             {   "Option Value",
 883                 "wtp.tpi.opt.val",
 884                 FT_NONE, BASE_NONE, NULL, 0x00,
 885                 "The value that is supplied with this option", HFILL
 886             }
 887         },
 888         { &hf_wtp_tpi_info,
 889             {   "Information",
 890                 "wtp.tpi.info",
 891                 FT_NONE, BASE_NONE, NULL, 0x00,
 892                 "The information being send by this TPI", HFILL
 893             }
 894         },
 895
 896         /* Fragment fields */
 897         { &hf_wtp_fragment_overlap,
 898             {   "Fragment overlap",
 899                 "wtp.fragment.overlap",
 900                 FT_BOOLEAN, BASE_NONE, NULL, 0x0,
 901                 "Fragment overlaps with other fragments", HFILL
 902             }
 903         },
 904         { &hf_wtp_fragment_overlap_conflict,
 905             {   "Conflicting data in fragment overlap",
 906                 "wtp.fragment.overlap.conflict",
 907                 FT_BOOLEAN, BASE_NONE, NULL, 0x0,
 908                 "Overlapping fragments contained conflicting data", HFILL
 909             }
 910         },
 911         { &hf_wtp_fragment_multiple_tails,
 912             {   "Multiple tail fragments found",
 913                 "wtp.fragment.multipletails",
 914                 FT_BOOLEAN, BASE_NONE, NULL, 0x0,
 915                 "Several tails were found when defragmenting the packet", HFILL
 916             }
 917         },
 918         { &hf_wtp_fragment_too_long_fragment,
 919             {   "Fragment too long",
 920                 "wtp.fragment.toolongfragment",
 921                 FT_BOOLEAN, BASE_NONE, NULL, 0x0,
 922                 "Fragment contained data past end of packet", HFILL
 923             }
 924         },
 925         { &hf_wtp_fragment_error,
 926             {   "Defragmentation error",
 927                 "wtp.fragment.error",
 928                 FT_FRAMENUM, BASE_NONE, NULL, 0x0,
 929                 "Defragmentation error due to illegal fragments", HFILL
 930             }
 931         },
 932         { &hf_wtp_fragment,
 933             {   "WTP Fragment",
 934                 "wtp.fragment",
 935                 FT_FRAMENUM, BASE_NONE, NULL, 0x0,
 936                 "WTP Fragment", HFILL
 937             }
 938         },
 939         { &hf_wtp_fragments,
 940             {   "WTP Fragments",
 941                 "wtp.fragments",
 942                 FT_NONE, BASE_NONE, NULL, 0x0,
 943                 "WTP Fragments", HFILL
 944             }
 945         },
 946     };
 947
 948     /* Setup protocol subtree array */
 949     static gint *ett[] = {
 950         &ett_wtp,
 951         &ett_wtp_sub_pdu_tree,
 952         &ett_header,
 953         &ett_tpilist,
 954         &ett_wsp_fragments,
 955         &ett_wtp_fragment,
 956     };
 957
 958     /* Register the protocol name and description */
 959     proto_wtp = proto_register_protocol(
 960         "Wireless Transaction Protocol",   /* protocol name for use by ethereal */
 961         "WTP",                             /* short version of name */
 962         "wap-wsp-wtp"                      /* Abbreviated protocol name, should Match IANA
 963                                             < URL:http://www.isi.edu/in-notes/iana/assignments/port-numbers/ >
 964                                             */
 965     );
 966
 967     /* Required calls to register the header fields and subtrees used */
 968     proto_register_field_array(proto_wtp, hf, array_length(hf));
 969     proto_register_subtree_array(ett, array_length(ett));
 970
 971     register_dissector("wtp", dissect_wtp_fromwap, proto_wtp);
 972     register_dissector("wtp-udp", dissect_wtp_fromudp, proto_wtp);
 973     register_init_routine(wtp_defragment_init);
 974 };
 975
 976 void
 977 proto_reg_handoff_wtp(void)
 978 {
 979     dissector_handle_t wtp_fromudp_handle;
 980
 981     /*
 982      * Get a handle for the connection-oriented WSP dissector - if WTP
 983      * PDUs have data, it is WSP.
 984      */
 985     wsp_handle = find_dissector("wsp-co");
 986
 987     wtp_fromudp_handle = find_dissector("wtp-udp");
 988     dissector_add("udp.port", UDP_PORT_WTP_WSP, wtp_fromudp_handle);
 989     dissector_add("smpp.udh.port", UDP_PORT_WTP_WSP, wtp_fromudp_handle);
 990 }