packet-gsm_sms_ud.c

   1 /* packet-gsm_sms_ud.c
   2  * Routines for GSM SMS TP-UD (GSM 03.40) dissection
   3  *
   4  * $Id: packet-gsm_sms_ud.c,v 1.5 2004/01/29 21:19:10 obiot Exp $
   5  *
   6  * Refer to the AUTHORS file or the AUTHORS section in the man page
   7  * for contacting the author(s) of this file.
   8  *
   9  * Separated from the SMPP dissector by Chris Wilson.
  10  *
  11  * UDH and WSP dissection of SMS message, Short Message reassembly,
  12  * "Decode Short Message with Port Number UDH as CL-WSP" preference,
  13  * "Always try subdissection of 1st fragment" preference,
  14  * provided by Olivier Biot.
  15  *
  16  * Note on SMS Message reassembly
  17  * ------------------------------
  18  *   The current Short Message reassembly is possible thanks to the
  19  *   message identifier (8 or 16 bit identifier). It is able to reassemble
  20  *   short messages that are sent over either the same SMPP connection or
  21  *   distinct SMPP connections. Normally the reassembly code is able to deal
  22  *   with duplicate message identifiers since the fragment_add_seq_check()
  23  *   call is used.
  24  *
  25  *   The SMS TP-UD preference "always try subdissection of 1st fragment" allows
  26  *   a subdissector to be called for the first Short Message fragment,
  27  *   even if reassembly is not possible. This way partial dissection
  28  *   is still possible. This preference is switched off by default.
  29  *
  30  * Note on Short Message decoding as CL-WSP
  31  * ----------------------------------------
  32  *    The SMS TP-UD preference "port_number_udh_means_wsp" is switched off
  33  *    by default. If it is enabled, then any Short Message with a Port Number
  34  *    UDH will be decoded as CL-WSP if:
  35  *    -  The Short Message is not segmented
  36  *    -  The entire segmented Short Message is reassembled
  37  *    -  It is the 1st segment of an unreassembled Short Message (if the
  38  *       "always try subdissection of 1st fragment" preference is enabled)
  39  *
  40  * Ethereal - Network traffic analyzer
  41  * By Gerald Combs <gerald@ethereal.com>
  42  * Copyright 1998 Gerald Combs
  43  *
  44  * This program is free software; you can redistribute it and/or
  45  * modify it under the terms of the GNU General Public License
  46  * as published by the Free Software Foundation; either version 2
  47  * of the License, or (at your option) any later version.
  48  *
  49  * This program is distributed in the hope that it will be useful,
  50  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  51  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  52  * GNU General Public License for more details.
  53  *
  54  * You should have received a copy of the GNU General Public License
  55  * along with this program; if not, write to the Free Software
  56  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  57  */
  58
  59 #ifdef HAVE_CONFIG_H
  60 # include "config.h"
  61 #endif
  62
  63 #include <stdio.h>
  64 #include <stdlib.h>
  65 #include <string.h>
  66 #include <time.h>
  67
  68 #include <glib.h>
  69
  70 #include <epan/packet.h>
  71
  72 #include "prefs.h"
  73 #include "reassemble.h"
  74
  75 static void dissect_gsm_sms_ud(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree);
  76
  77 static int proto_gsm_sms_ud = -1;
  78
  79 /*
  80  * Short Message fragment handling
  81  */
  82 static int hf_gsm_sms_ud_fragments = -1;
  83 static int hf_gsm_sms_ud_fragment = -1;
  84 static int hf_gsm_sms_ud_fragment_overlap = -1;
  85 static int hf_gsm_sms_ud_fragment_overlap_conflicts = -1;
  86 static int hf_gsm_sms_ud_fragment_multiple_tails = -1;
  87 static int hf_gsm_sms_ud_fragment_too_long_fragment = -1;
  88 static int hf_gsm_sms_ud_fragment_error = -1;
  89 static int hf_gsm_sms_ud_reassembled_in = -1;
  90 /*
  91  * User Data Header section
  92  */
  93 static int hf_gsm_sms_udh_length = -1;
  94 static int hf_gsm_sms_udh_iei = -1;
  95 static int hf_gsm_sms_udh_multiple_messages = -1;
  96 static int hf_gsm_sms_udh_multiple_messages_msg_id = -1;
  97 static int hf_gsm_sms_udh_multiple_messages_msg_parts = -1;
  98 static int hf_gsm_sms_udh_multiple_messages_msg_part = -1;
  99 static int hf_gsm_sms_udh_ports = -1;
 100 static int hf_gsm_sms_udh_ports_src = -1;
 101 static int hf_gsm_sms_udh_ports_dst = -1;
 102
 103 static gint ett_gsm_sms = -1;
 104 static gint ett_udh = -1;
 105 static gint ett_udh_ie = -1;
 106 static gint ett_gsm_sms_ud_fragment = -1;
 107 static gint ett_gsm_sms_ud_fragments = -1;
 108
 109 /* Subdissector declarations */
 110 static dissector_table_t gsm_sms_dissector_table;
 111
 112 /* Short Message reassembly */
 113 static GHashTable *sm_fragment_table = NULL;
 114 static GHashTable *sm_reassembled_table = NULL;
 115
 116 static const fragment_items sm_frag_items = {
 117         /* Fragment subtrees */
 118         &ett_gsm_sms_ud_fragment,
 119         &ett_gsm_sms_ud_fragments,
 120         /* Fragment fields */
 121         &hf_gsm_sms_ud_fragments,
 122         &hf_gsm_sms_ud_fragment,
 123         &hf_gsm_sms_ud_fragment_overlap,
 124         &hf_gsm_sms_ud_fragment_overlap_conflicts,
 125         &hf_gsm_sms_ud_fragment_multiple_tails,
 126         &hf_gsm_sms_ud_fragment_too_long_fragment,
 127         &hf_gsm_sms_ud_fragment_error,
 128         /* Reassembled in field */
 129         &hf_gsm_sms_ud_reassembled_in,
 130         /* Tag */
 131         "Short Message fragments"
 132 };
 133
 134 /* Dissect all SM data as WSP if the UDH contains a Port Number IE */
 135 static gboolean port_number_udh_means_wsp = FALSE;
 136 /* Always try dissecting the 1st fragment of a SM,
 137  * even if it is not reassembled */
 138 static gboolean try_dissect_1st_frag = FALSE;
 139 /* Prevent subdissectors changing column data */
 140 static gboolean prevent_subdissectors_changing_columns = FALSE;
 141
 142 static dissector_handle_t wsp_handle;
 143
 144 static void
 145 gsm_sms_ud_defragment_init (void)
 146 {
 147         fragment_table_init (&sm_fragment_table);
 148         reassembled_table_init(&sm_reassembled_table);
 149 }
 150
 151 /*
 152  * Value-arrays for field-contents
 153  */
 154 /* 3GPP TS 23.040 V6.1.0 (2003-06) */
 155 static const value_string vals_udh_iei[] = {
 156         { 0x00, "SMS - Concatenated short messages, 8-bit reference number" },
 157         { 0x01, "SMS - Special SMS Message Indication" },
 158         { 0x02, "Reserved" },
 159         { 0x03, "Value not used to avoid misinterpretation as <LF> character" },
 160         { 0x04, "SMS - Application port addressing scheme, 8 bit address" },
 161         { 0x05, "SMS - Application port addressing scheme, 16 bit address" },
 162         { 0x06, "SMS - SMSC Control Parameters" },
 163         { 0x07, "SMS - UDH Source Indicator" },
 164         { 0x08, "SMS - Concatenated short message, 16-bit reference number" },
 165         { 0x09, "SMS - Wireless Control Message Protocol" },
 166         { 0x0A, "EMS - Text Formatting" },
 167         { 0x0B, "EMS - Predefined Sound" },
 168         { 0x0C, "EMS - User Defined Sound (iMelody max 128 bytes)" },
 169         { 0x0D, "EMS - Predefined Animation" },
 170         { 0x0E, "EMS - Large Animation (16*16 times 4 = 32*4 =128 bytes)" },
 171         { 0x0F, "EMS - Small Animation (8*8 times 4 = 8*4 =32 bytes)" },
 172         { 0x10, "EMS - Large Picture (32*32 = 128 bytes)" },
 173         { 0x11, "EMS - Small Picture (16*16 = 32 bytes)" },
 174         { 0x12, "EMS - Variable Picture" },
 175         { 0x13, "EMS - User prompt indicator" },
 176         { 0x14, "EMS - Extended Object" },
 177         { 0x15, "EMS - Reused Extended Object" },
 178         { 0x16, "EMS - Compression Control" },
 179         { 0x17, "EMS - Object Distribution Indicator" },
 180         { 0x18, "EMS - Standard WVG object" },
 181         { 0x19, "EMS - Character Size WVG object" },
 182         { 0x1A, "EMS - Extended Object Data Request Command" },
 183         { 0x20, "SMS - RFC 822 E-Mail Header" },
 184         { 0x21, "SMS - Hyperlink format element" },
 185         { 0x22, "SMS - Reply Address Element" },
 186         { 0x00, NULL }
 187 };
 188
 189
 190 /* Parse Short Message, only if UDH present
 191  * (otherwise this function is not called).
 192  * Call WSP dissector if port matches WSP traffic.
 193  */
 194 static void
 195 parse_gsm_sms_ud_message(proto_tree *sm_tree, tvbuff_t *tvb, packet_info *pinfo,
 196                 proto_tree *top_tree)
 197 {
 198         tvbuff_t *sm_tvb = NULL;
 199         proto_item *subtree, *tree;
 200         guint8 udh_len, udh, len;
 201         guint sm_len = tvb_reported_length (tvb);
 202         guint sm_data_len;
 203         guint32 i = 0;
 204         /* Multiple Messages UDH */
 205         gboolean is_fragmented = FALSE;
 206         fragment_data *fd_sm = NULL;
 207         guint16 sm_id = 0, frags = 0, frag = 0;
 208         gboolean save_fragmented = FALSE, try_gsm_sms_ud_reassemble = FALSE;
 209         /* SMS Message reassembly */
 210         gboolean reassembled = FALSE;
 211         guint32 reassembled_in = 0;
 212         /* Port Number UDH */
 213         guint16 p_src = 0, p_dst = 0;
 214         gboolean ports_available = FALSE;
 215
 216         udh_len = tvb_get_guint8(tvb, i++);
 217         tree = proto_tree_add_uint(sm_tree, hf_gsm_sms_udh_length, tvb, 0, 1, udh_len);
 218         tree = proto_item_add_subtree(tree, ett_udh);
 219         while (i < udh_len) {
 220                 udh = tvb_get_guint8(tvb, i++);
 221                 len = tvb_get_guint8(tvb, i++);
 222                 subtree = proto_tree_add_uint(tree, hf_gsm_sms_udh_iei,
 223                                 tvb, i-2, 2+len, udh);
 224                 switch (udh) {
 225                         case 0x00: /* Multiple messages - 8-bit message ID */
 226                                 if (len == 3) {
 227                                         sm_id = tvb_get_guint8(tvb, i++);
 228                                         frags = tvb_get_guint8(tvb, i++);
 229                                         frag  = tvb_get_guint8(tvb, i++);
 230                                         if (frags > 1)
 231                                                 is_fragmented = TRUE;
 232                                         proto_item_append_text(subtree,
 233                                                         ": message %u, part %u of %u", sm_id, frag, frags);
 234                                         subtree = proto_item_add_subtree(subtree,
 235                                                         ett_udh_ie);
 236                                         proto_tree_add_uint (subtree,
 237                                                         hf_gsm_sms_udh_multiple_messages_msg_id,
 238                                                         tvb, i-3, 1, sm_id);
 239                                         proto_tree_add_uint (subtree,
 240                                                         hf_gsm_sms_udh_multiple_messages_msg_parts,
 241                                                         tvb, i-2, 1, frags);
 242                                         proto_tree_add_uint (subtree,
 243                                                         hf_gsm_sms_udh_multiple_messages_msg_part,
 244                                                         tvb, i-1, 1, frag);
 245                                 } else {
 246                                         proto_item_append_text(subtree, " - Invalid format!");
 247                                         i += len;
 248                                 }
 249                                 break;
 250
 251                         case 0x08: /* Multiple messages - 16-bit message ID */
 252                                 if (len == 4) {
 253                                         sm_id = tvb_get_ntohs(tvb, i); i += 2;
 254                                         frags = tvb_get_guint8(tvb, i++);
 255                                         frag  = tvb_get_guint8(tvb, i++);
 256                                         if (frags > 1)
 257                                                 is_fragmented = TRUE;
 258                                         proto_item_append_text(subtree,
 259                                                         ": message %u, part %u of %u", sm_id, frag, frags);
 260                                         subtree = proto_item_add_subtree(subtree,
 261                                                         ett_udh_ie);
 262                                         proto_tree_add_uint (subtree,
 263                                                         hf_gsm_sms_udh_multiple_messages_msg_id,
 264                                                         tvb, i-4, 2, sm_id);
 265                                         proto_tree_add_uint (subtree,
 266                                                         hf_gsm_sms_udh_multiple_messages_msg_parts,
 267                                                         tvb, i-2, 1, frags);
 268                                         proto_tree_add_uint (subtree,
 269                                                         hf_gsm_sms_udh_multiple_messages_msg_part,
 270                                                         tvb, i-1, 1, frag);
 271                                 } else {
 272                                         proto_item_append_text(subtree, " - Invalid format!");
 273                                         i += len;
 274                                 }
 275                                 break;
 276
 277                         case 0x04: /* Port Number UDH - 8-bit address */
 278                                 if (len == 2) { /* Port fields */
 279                                         p_dst = tvb_get_guint8(tvb, i++);
 280                                         p_src = tvb_get_guint8(tvb, i++);
 281                                         proto_item_append_text(subtree,
 282                                                         ": source port %u, destination port %u",
 283                                                         p_src, p_dst);
 284                                         subtree = proto_item_add_subtree(subtree, ett_udh_ie);
 285                                         proto_tree_add_uint (subtree, hf_gsm_sms_udh_ports_dst,
 286                                                         tvb, i-2, 1, p_dst);
 287                                         proto_tree_add_uint (subtree, hf_gsm_sms_udh_ports_src,
 288                                                         tvb, i-1, 1, p_src);
 289                                         ports_available = TRUE;
 290                                 } else {
 291                                         proto_item_append_text(subtree, " - Invalid format!");
 292                                         i += len;
 293                                 }
 294                                 break;
 295
 296                         case 0x05: /* Port Number UDH - 16-bit address */
 297                                 if (len == 4) { /* Port fields */
 298                                         p_dst = tvb_get_ntohs(tvb, i); i += 2;
 299                                         p_src = tvb_get_ntohs(tvb, i); i += 2;
 300                                         proto_item_append_text(subtree,
 301                                                         ": source port %u, destination port %u",
 302                                                         p_src, p_dst);
 303                                         subtree = proto_item_add_subtree(subtree, ett_udh_ie);
 304                                         proto_tree_add_uint (subtree, hf_gsm_sms_udh_ports_dst,
 305                                                         tvb, i-4, 2, p_dst);
 306                                         proto_tree_add_uint (subtree, hf_gsm_sms_udh_ports_src,
 307                                                         tvb, i-2, 2, p_src);
 308                                         ports_available = TRUE;
 309                                 } else {
 310                                         proto_item_append_text(subtree, " - Invalid format!");
 311                                         i += len;
 312                                 }
 313                                 break;
 314
 315                         default:
 316                                 i += len;
 317                                 break;
 318                 }
 319         }
 320         if (tvb_reported_length_remaining(tvb, i) <= 0)
 321                 return; /* No more data */
 322
 323         /*
 324          * XXX - where does the "1" come from?  If it weren't there,
 325          * "sm_data_len" would, I think, be the same as
 326          * "tvb_reported_length_remaining(tvb, i)".
 327          *
 328          * I think that the above check ensures that "sm_len" won't
 329          * be less than or equal to "udh_len", so it ensures that
 330          * "sm_len" won't be less than "1 + udh_len", so we don't
 331          * have to worry about "sm_data_len" being negative.
 332          */
 333         sm_data_len = sm_len - (1 + udh_len);
 334         if (sm_data_len == 0)
 335                 return; /* no more data */
 336
 337         /*
 338          * Try reassembling the packets.
 339          * XXX - fragment numbers are 1-origin, but the fragment number
 340          * field could be 0.
 341          * Should we flag a fragmented message with a fragment number field
 342          * of 0?
 343          * What if the fragment count is 0?  Should we flag that as well?
 344          */
 345         if ( is_fragmented && frag != 0 && frags != 0 &&
 346             tvb_bytes_exist (tvb, i, sm_data_len) ) {
 347                 try_gsm_sms_ud_reassemble = TRUE;
 348                 save_fragmented = pinfo->fragmented;
 349                 pinfo->fragmented = TRUE;
 350                 fd_sm = fragment_add_seq_check (tvb, i, pinfo,
 351                                 sm_id, /* guint32 ID for fragments belonging together */
 352                                 sm_fragment_table, /* list of message fragments */
 353                                 sm_reassembled_table, /* list of reassembled messages */
 354                                 frag-1, /* guint32 fragment sequence number */
 355                                 sm_data_len, /* guint32 fragment length */
 356                                 (frag != frags)); /* More fragments? */
 357                 if (fd_sm) {
 358                         reassembled = TRUE;
 359                         reassembled_in = fd_sm->reassembled_in;
 360                 }
 361                 sm_tvb = process_reassembled_data(tvb, i, pinfo,
 362                     "Reassembled Short Message", fd_sm, &sm_frag_items,
 363                     NULL, sm_tree);
 364                 if (reassembled) { /* Reassembled */
 365                         if (check_col (pinfo->cinfo, COL_INFO))
 366                                 col_append_str (pinfo->cinfo, COL_INFO,
 367                                                 " (Short Message Reassembled)");
 368                 } else {
 369                         /* Not last packet of reassembled Short Message */
 370                         if (check_col (pinfo->cinfo, COL_INFO))
 371                                 col_append_fstr (pinfo->cinfo, COL_INFO,
 372                                                 " (Short Message fragment %u of %u)", frag, frags);
 373                 }
 374         } /* Else: not fragmented */
 375
 376         if (! sm_tvb) /* One single Short Message, or not reassembled */
 377                 sm_tvb = tvb_new_subset (tvb, i, -1, -1);
 378         /* Try calling a subdissector */
 379         if (sm_tvb) {
 380                 if ((reassembled && pinfo->fd->num == reassembled_in)
 381                         || frag==0 || (frag==1 && try_dissect_1st_frag)) {
 382                         /* Try calling a subdissector only if:
 383                          *  - the Short Message is reassembled in this very packet,
 384                          *  - the Short Message consists of only one "fragment",
 385                          *  - the preference "Always Try Dissection for 1st SM fragment"
 386                          *    is switched on, and this is the SM's 1st fragment. */
 387                         if ( ports_available ) {
 388                                 gboolean disallow_write = FALSE; /* TRUE if we changed writability
 389                                                                     of the columns of the summary */
 390                                 if ( prevent_subdissectors_changing_columns && col_get_writable(pinfo->cinfo) ) {
 391                                         disallow_write = TRUE;
 392                                         col_set_writable(pinfo->cinfo, FALSE);
 393                                 }
 394
 395                                 if ( port_number_udh_means_wsp ) {
 396                                         call_dissector (wsp_handle, sm_tvb, pinfo, top_tree);
 397                                 } else {
 398                                         if (! dissector_try_port(gsm_sms_dissector_table, p_src,
 399                                                                 sm_tvb, pinfo, top_tree)) {
 400                                                 if (! dissector_try_port(gsm_sms_dissector_table, p_dst,
 401                                                                         sm_tvb, pinfo, top_tree)) {
 402                                                         if (sm_tree) { /* Only display if needed */
 403                                                                 proto_tree_add_text (sm_tree, sm_tvb, 0, -1,
 404                                                                                 "Short Message body");
 405                                                         }
 406                                                 }
 407                                         }
 408                                 }
 409
 410                                 if ( disallow_write )
 411                                         col_set_writable(pinfo->cinfo, TRUE);
 412                         } else { /* No ports IE */
 413                                 proto_tree_add_text (sm_tree, sm_tvb, 0, -1,
 414                                                 "Short Message body");
 415                         }
 416                 } else {
 417                         /* The packet is not reassembled,
 418                          * or it is reassembled in another packet */
 419                         proto_tree_add_text (sm_tree, sm_tvb, 0, -1,
 420                                         "Unreassembled Short Message fragment %u of %u",
 421                                         frag, frags);
 422                 }
 423         }
 424
 425         if (try_gsm_sms_ud_reassemble) /* Clean up defragmentation */
 426                 pinfo->fragmented = save_fragmented;
 427         return;
 428 }
 429
 430 static void
 431 dissect_gsm_sms_ud(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 432 {
 433         proto_item *ti;
 434         proto_tree *subtree;
 435         ti = proto_tree_add_item(tree, proto_gsm_sms_ud, tvb, 0, -1, TRUE);
 436         subtree = proto_item_add_subtree(ti, ett_gsm_sms);
 437         parse_gsm_sms_ud_message(subtree, tvb, pinfo, tree);
 438 }
 439
 440 /* Register the protocol with Ethereal */
 441 void
 442 proto_register_gsm_sms_ud(void)
 443 {
 444         module_t *gsm_sms_ud_module; /* Preferences for GSM SMS UD */
 445
 446     /* Setup list of header fields      */
 447     static hf_register_info hf[] = {
 448         /*
 449          * User Data Header
 450          */
 451         {   &hf_gsm_sms_udh_iei,
 452                 {       "IE Id", "gsm-sms-ud.udh.iei",
 453                 FT_UINT8, BASE_HEX, VALS(vals_udh_iei), 0x00,
 454                 "Name of the User Data Header Information Element.",
 455                 HFILL
 456                 }
 457         },
 458         {   &hf_gsm_sms_udh_length,
 459             {   "UDH Length", "gsm-sms-ud.udh.len",
 460                 FT_UINT8, BASE_DEC, NULL, 0x00,
 461                 "Length of the User Data Header (bytes)",
 462                 HFILL
 463             }
 464         },
 465         {   &hf_gsm_sms_udh_multiple_messages,
 466             {   "Multiple messages UDH", "gsm-sms-ud.udh.mm",
 467                 FT_NONE, BASE_NONE, NULL, 0x00,
 468                 "Multiple messages User Data Header",
 469                 HFILL
 470             }
 471         },
 472         {   &hf_gsm_sms_udh_multiple_messages_msg_id,
 473             {   "Message identifier", "gsm-sms-ud.udh.mm.msg_id",
 474                 FT_UINT16, BASE_DEC, NULL, 0x00,
 475                 "Identification of the message",
 476                 HFILL
 477             }
 478         },
 479         {   &hf_gsm_sms_udh_multiple_messages_msg_parts,
 480             {   "Message parts", "gsm-sms-ud.udh.mm.msg_parts",
 481                 FT_UINT8, BASE_DEC, NULL, 0x00,
 482                 "Total number of message parts (fragments)",
 483                 HFILL
 484             }
 485         },
 486         {   &hf_gsm_sms_udh_multiple_messages_msg_part,
 487             {   "Message part number", "gsm-sms-ud.udh.mm.msg_part",
 488                 FT_UINT8, BASE_DEC, NULL, 0x00,
 489                 "Message part (fragment) sequence number",
 490                 HFILL
 491             }
 492         },
 493         {   &hf_gsm_sms_udh_ports,
 494             {   "Port number UDH", "gsm-sms-ud.udh.ports",
 495                 FT_NONE, BASE_NONE, NULL, 0x00,
 496                 "Port number User Data Header",
 497                 HFILL
 498             }
 499         },
 500         {   &hf_gsm_sms_udh_ports_src,
 501             {   "Source port", "gsm-sms-ud.udh.ports.src",
 502                 FT_UINT8, BASE_DEC, NULL, 0x00,
 503                 "Source port",
 504                 HFILL
 505             }
 506         },
 507         {   &hf_gsm_sms_udh_ports_dst,
 508             {   "Destination port", "gsm-sms-ud.udh.ports.dst",
 509                 FT_UINT8, BASE_DEC, NULL, 0x00,
 510                 "Destination port",
 511                 HFILL
 512             }
 513         },
 514         /*
 515          * Short Message fragment reassembly
 516          */
 517         {       &hf_gsm_sms_ud_fragments,
 518                 {       "Short Message fragments", "gsm-sms-ud.fragments",
 519                         FT_NONE, BASE_NONE, NULL, 0x00,
 520                         "GSM Short Message fragments",
 521                         HFILL
 522                 }
 523         },
 524         {       &hf_gsm_sms_ud_fragment,
 525                 {       "Short Message fragment", "gsm-sms-ud.fragment",
 526                         FT_FRAMENUM, BASE_NONE, NULL, 0x00,
 527                         "GSM Short Message fragment",
 528                         HFILL
 529                 }
 530         },
 531         {       &hf_gsm_sms_ud_fragment_overlap,
 532                 {       "Short Message fragment overlap", "gsm-sms-ud.fragment.overlap",
 533                         FT_BOOLEAN, BASE_NONE, NULL, 0x00,
 534                         "GSM Short Message fragment overlaps with other fragment(s)",
 535                         HFILL
 536                 }
 537         },
 538         {       &hf_gsm_sms_ud_fragment_overlap_conflicts,
 539                 {       "Short Message fragment overlapping with conflicting data",
 540                         "gsm-sms-ud.fragment.overlap.conflicts",
 541                         FT_BOOLEAN, BASE_NONE, NULL, 0x00,
 542                         "GSM Short Message fragment overlaps with conflicting data",
 543                         HFILL
 544                 }
 545         },
 546         {       &hf_gsm_sms_ud_fragment_multiple_tails,
 547                 {       "Short Message has multiple tail fragments",
 548                         "gsm-sms-ud.fragment.multiple_tails",
 549                         FT_BOOLEAN, BASE_NONE, NULL, 0x00,
 550                         "GSM Short Message fragment has multiple tail fragments",
 551                         HFILL
 552                 }
 553         },
 554         {       &hf_gsm_sms_ud_fragment_too_long_fragment,
 555                 {       "Short Message fragment too long",
 556                         "gsm-sms-ud.fragment.too_long_fragment",
 557                         FT_BOOLEAN, BASE_NONE, NULL, 0x00,
 558                         "GSM Short Message fragment data goes beyond the packet end",
 559                         HFILL
 560                 }
 561         },
 562         {       &hf_gsm_sms_ud_fragment_error,
 563                 {       "Short Message defragmentation error", "gsm-sms-ud.fragment.error",
 564                         FT_FRAMENUM, BASE_NONE, NULL, 0x00,
 565                         "GSM Short Message defragmentation error due to illegal fragments",
 566                         HFILL
 567                 }
 568         },
 569         {       &hf_gsm_sms_ud_reassembled_in,
 570                 {       "Reassembled in",
 571                         "gsm-sms-ud.reassembled.in",
 572                         FT_FRAMENUM, BASE_NONE, NULL, 0x00,
 573                         "GSM Short Message has been reassembled in this packet.", HFILL
 574                 }
 575         },
 576         };
 577
 578     static gint *ett[] = {
 579         &ett_gsm_sms,
 580         &ett_udh,
 581         &ett_udh_ie,
 582         &ett_gsm_sms_ud_fragment,
 583         &ett_gsm_sms_ud_fragments,
 584     };
 585     /* Register the protocol name and description */
 586     proto_gsm_sms_ud = proto_register_protocol(
 587             "GSM Short Message Service User Data",      /* Name */
 588             "GSM SMS UD",                       /* Short name */
 589             "gsm-sms-ud");                      /* Filter name */
 590
 591     /* Required function calls to register header fields and subtrees used */
 592     proto_register_field_array(proto_gsm_sms_ud, hf, array_length(hf));
 593     proto_register_subtree_array(ett, array_length(ett));
 594
 595     /* Subdissector code */
 596     gsm_sms_dissector_table = register_dissector_table("gsm-sms-ud.udh.port",
 597             "GSM SMS port IE in UDH", FT_UINT16, BASE_DEC);
 598
 599     /* Preferences for GSM SMS UD */
 600     gsm_sms_ud_module = prefs_register_protocol (proto_gsm_sms_ud, NULL);
 601     prefs_register_bool_preference (gsm_sms_ud_module,
 602             "port_number_udh_means_wsp",
 603             "Port Number IE in UDH always triggers CL-WSP dissection",
 604             "Always decode a GSM Short Message as Connectionless WSP "
 605             "if a Port Number Information Element is present "
 606             "in the SMS User Data Header.",
 607             &port_number_udh_means_wsp);
 608     prefs_register_bool_preference (gsm_sms_ud_module, "try_dissect_1st_fragment",
 609             "Always try subdissection of 1st Short Message fragment",
 610             "Always try subdissection of the 1st fragment of a fragmented "
 611             "GSM Short Message. If reassembly is possible, the Short Message "
 612             "may be dissected twice (once as a short frame, once in its "
 613             "entirety).",
 614             &try_dissect_1st_frag);
 615     prefs_register_bool_preference (gsm_sms_ud_module, "prevent_dissectors_chg_cols",
 616             "Prevent sub-dissectors from changing column data",
 617             "Prevent sub-dissectors from replacing column data with their "
 618             "own. Eg. Prevent WSP dissector overwriting SMPP information.",
 619             &prevent_subdissectors_changing_columns);
 620
 621     register_dissector("gsm-sms-ud", dissect_gsm_sms_ud, proto_gsm_sms_ud);
 622
 623     /* GSM SMS UD dissector initialization routines */
 624     register_init_routine (gsm_sms_ud_defragment_init);
 625 }
 626
 627 void
 628 proto_reg_handoff_gsm_sms_ud(void)
 629 {
 630         dissector_handle_t gsm_sms_ud_handle;
 631         gsm_sms_ud_handle = create_dissector_handle(dissect_gsm_sms_ud,
 632                         proto_gsm_sms_ud);
 633
 634         wsp_handle = find_dissector("wsp-cl");
 635         g_assert(wsp_handle);
 636 }
 637
 638
 639