plugins/wimax/msg_dreg.c

   1 /* msg_dreg.c
   2  * WiMax MAC Management DREG-REQ, DREG-CMD Message decoders
   3  *
   4  * Copyright (c) 2007 by Intel Corporation.
   5  *
   6  * Author: John R. Underwood <junderx@yahoo.com>
   7  *
   8  * $Id$
   9  *
  10  * Wireshark - Network traffic analyzer
  11  * By Gerald Combs <gerald@wireshark.org>
  12  * Copyright 1999 Gerald Combs
  13  *
  14  * This program is free software; you can redistribute it and/or
  15  * modify it under the terms of the GNU General Public License
  16  * as published by the Free Software Foundation; either version 2
  17  * of the License, or (at your option) any later version.
  18  *
  19  * This program is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License
  25  * along with this program; if not, write to the Free Software
  26  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  27  */
  28
  29 /* Include files */
  30
  31 #include "config.h"
  32
  33 #include "moduleinfo.h"
  34
  35 #include <glib.h>
  36 #include <epan/packet.h>
  37 #include "crc.h"
  38 #include "wimax_tlv.h"
  39 #include "wimax_mac.h"
  40 #include "wimax_utils.h"
  41
  42 extern  gboolean include_cor2_changes;
  43
  44 /* Forward reference */
  45 static void dissect_dreg_tlv(proto_tree *dreg_tree, gint tlv_type, tvbuff_t *tvb, guint tlv_offset, guint tlv_len);
  46
  47 static gint proto_mac_mgmt_msg_dreg_req_decoder = -1;
  48 static gint proto_mac_mgmt_msg_dreg_cmd_decoder = -1;
  49
  50 static gint ett_mac_mgmt_msg_dreg_decoder = -1;
  51
  52 /* Setup protocol subtree array */
  53 static gint *ett[] =
  54 {
  55         &ett_mac_mgmt_msg_dreg_decoder,
  56 };
  57
  58 /* DREG fields */
  59 /* static gint hf_ack_type_reserved = -1; */
  60 static gint hf_dreg_cmd_action = -1;
  61 static gint hf_dreg_cmd_action_cor2 = -1;
  62 static gint hf_dreg_cmd_reserved = -1;
  63 static gint hf_dreg_paging_cycle = -1;
  64 static gint hf_dreg_paging_offset = -1;
  65 static gint hf_dreg_paging_group_id = -1;
  66 static gint hf_dreg_req_duration = -1;
  67 static gint hf_paging_controller_id = -1;
  68 static gint hf_mac_hash_skip_threshold = -1;
  69 static gint hf_dreg_paging_cycle_request = -1;
  70 static gint hf_dreg_retain_ms_service_sbc = -1;
  71 static gint hf_dreg_retain_ms_service_pkm = -1;
  72 static gint hf_dreg_retain_ms_service_reg = -1;
  73 static gint hf_dreg_retain_ms_service_network_address = -1;
  74 static gint hf_dreg_retain_ms_service_tod = -1;
  75 static gint hf_dreg_retain_ms_service_tftp = -1;
  76 static gint hf_dreg_retain_ms_service_full_service = -1;
  77 static gint hf_dreg_consider_paging_pref = -1;
  78 static gint hf_tlv_value = -1;
  79 static gint hf_dreg_req_action = -1;
  80 static gint hf_dreg_req_reserved = -1;
  81 static gint hf_dreg_invalid_tlv = -1;
  82
  83 /* STRING RESOURCES */
  84 static const value_string vals_dreg_req_code[] = {
  85         {0, "SS De-Registration request from BS and network"},
  86         {1, "MS request for De-Registration from serving BS and initiation of Idle Mode"},
  87         {2, "MS response for the Unsolicited De-Registration initiated by BS"},
  88         {3, "Reject for the unsolicited DREG-CMD with action \
  89 code 05 (idle mode request) by the BS.  \
  90 Applicable only when MS has pending UL data to transmit"},
  91         {4, "Reserved"},
  92         {0,                             NULL}
  93 };
  94
  95 static const value_string vals_dreg_cmd_action[] = {
  96         {0, "SS shall immediately terminate service with the BS and \
  97 should attempt network entry at another BS"},
  98         {1, "SS shall listen to the current channel BS but shall not \
  99 transmit until an RES-CMD message or DREG-CMD with \
 100 Action Code 02 or 03 is received"},
 101         {2, "SS shall listen to the BS but only transmit \
 102 on the Basic, and Primary Management Connections"},
 103         {3, "SS shall return to normal operation and may transmit on \
 104 any of its active connections"},
 105         {4, "SS shall terminate current Normal Operations with the BS; \
 106 the BS shall transmit this action code only in response \
 107 to any SS DREG-REQ message"},
 108         {5, "MS shall immediately begin de-registration from serving \
 109 BS and request initiation of MS Idle Mode"},
 110         {6, "The MS may retransmit the DREG-REQ message after the \
 111 time duration (REQ-duration) provided in the message"},
 112         {7, "The MS shall not retransmit the DREG-REQ message and shall \
 113 wait for the DREG-CMD message. BS transmittal of a \
 114 subsequent DREG-CMD with Action Code 03 shall cancel \
 115 this restriction"},
 116         {0,                             NULL}
 117 };
 118
 119 static const value_string vals_dreg_cmd_action_cor2[] = {
 120         {0, "SS shall immediately terminate service with the BS and \
 121 should attempt network entry at another BS"},
 122         {1, "SS shall listen to the current channel BS but shall not \
 123 transmit until an RES-CMD message or DREG-CMD with \
 124 Action Code 02 or 03 is received"},
 125         {2, "SS shall listen to the BS but only transmit \
 126 on the Basic, and Primary Management Connections"},
 127         {3, "SS shall return to normal operation and may transmit on \
 128 any of its active connections"},
 129         {4, "Only valid in response to a DREG-REQ message with DREG \
 130 Code = 00.  SS shall terminate current Normal Operations with the BS"},
 131         {5, "MS shall immediately begin de-registration from serving \
 132 BS and request initiation of MS Idle Mode"},
 133         {6, "Only valid in response to a DREG-REQ message with DREG \
 134 Code = 01.  The MS may retransmit the DREG-REQ message after the \
 135 REQ-duration provided in the message; \
 136 BS sending a subsequent DREG-CMD message with \
 137 Action Code 03 cancels this restriction"},
 138         {0,                             NULL}
 139 };
 140
 141 /* Decode sub-TLV's of either DREG-REQ or DREG-CMD. */
 142 static void dissect_dreg_tlv(proto_tree *dreg_tree, gint tlv_type, tvbuff_t *tvb, guint tlv_offset, guint tlv_len)
 143 {
 144         switch (tlv_type) {
 145                 case DREG_PAGING_INFO:
 146                         proto_tree_add_item(dreg_tree, hf_dreg_paging_cycle, tvb, tlv_offset, 2, ENC_BIG_ENDIAN);
 147                         proto_tree_add_item(dreg_tree, hf_dreg_paging_offset, tvb, tlv_offset + 2, 1, ENC_BIG_ENDIAN);
 148                         proto_tree_add_item(dreg_tree, hf_dreg_paging_group_id, tvb, tlv_offset + 3, 2, ENC_BIG_ENDIAN);
 149                         break;
 150                 case DREG_REQ_DURATION:
 151                         proto_tree_add_item(dreg_tree, hf_dreg_req_duration, tvb, tlv_offset, 1, ENC_BIG_ENDIAN);
 152                         break;
 153                 case DREG_PAGING_CONTROLLER_ID:
 154                         proto_tree_add_item(dreg_tree, hf_paging_controller_id, tvb, tlv_offset, 6, ENC_NA);
 155                         break;
 156                 case DREG_IDLE_MODE_RETAIN_INFO:
 157                         proto_tree_add_item(dreg_tree, hf_dreg_retain_ms_service_sbc, tvb, tlv_offset, 1, ENC_BIG_ENDIAN);
 158                         proto_tree_add_item(dreg_tree, hf_dreg_retain_ms_service_pkm, tvb, tlv_offset, 1, ENC_BIG_ENDIAN);
 159                         proto_tree_add_item(dreg_tree, hf_dreg_retain_ms_service_reg, tvb, tlv_offset, 1, ENC_BIG_ENDIAN);
 160                         proto_tree_add_item(dreg_tree, hf_dreg_retain_ms_service_network_address, tvb, tlv_offset, 1, ENC_BIG_ENDIAN);
 161                         proto_tree_add_item(dreg_tree, hf_dreg_retain_ms_service_tod, tvb, tlv_offset, 1, ENC_BIG_ENDIAN);
 162                         proto_tree_add_item(dreg_tree, hf_dreg_retain_ms_service_tftp, tvb, tlv_offset, 1, ENC_BIG_ENDIAN);
 163                         proto_tree_add_item(dreg_tree, hf_dreg_retain_ms_service_full_service, tvb, tlv_offset, 1, ENC_BIG_ENDIAN);
 164                         proto_tree_add_item(dreg_tree, hf_dreg_consider_paging_pref, tvb, tlv_offset, 1, ENC_BIG_ENDIAN);
 165                         break;
 166                 case DREG_MAC_HASH_SKIP_THRESHOLD:
 167                         proto_tree_add_item(dreg_tree, hf_mac_hash_skip_threshold, tvb, tlv_offset, 2, ENC_BIG_ENDIAN);
 168                         break;
 169                 case DREG_PAGING_CYCLE_REQUEST:
 170                         proto_tree_add_item(dreg_tree, hf_dreg_paging_cycle_request, tvb, tlv_offset, 2, ENC_BIG_ENDIAN);
 171                         break;
 172                 default:
 173                         proto_tree_add_item(dreg_tree, hf_tlv_value, tvb, tlv_offset, tlv_len, ENC_NA);
 174                         break;
 175         }
 176 }
 177
 178 /* Register Wimax Mac Payload Protocol and Dissector */
 179 void proto_register_mac_mgmt_msg_dreg_req(void)
 180 {
 181         /* DREG fields display */
 182         static hf_register_info hf[] =
 183         {
 184                 {
 185                         &hf_dreg_consider_paging_pref,
 186                         {
 187                                 "Consider Paging Preference of each Service Flow in resource retention", "wmx.dreg.consider_paging_preference",
 188                                 FT_UINT8, BASE_DEC, NULL, 0x80, NULL, HFILL
 189                         }
 190                 },
 191                 {
 192                         &hf_dreg_invalid_tlv,
 193                         {
 194                                 "Invalid TLV", "wmx.dreg.invalid_tlv",
 195                                 FT_BYTES, BASE_NONE, NULL, 0, NULL, HFILL
 196                         }
 197                 },
 198                 {
 199                         &hf_mac_hash_skip_threshold,
 200                         {
 201                                 "MAC Hash Skip Threshold", "wmx.dreg.mac_hash_skip_threshold",
 202                                 FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL
 203                         }
 204                 },
 205                 {
 206                         &hf_paging_controller_id,
 207                         {
 208                                 "Paging Controller ID", "wmx.dreg.paging_controller_id",
 209                                 FT_ETHER, BASE_NONE, NULL, 0x0, NULL, HFILL
 210                         }
 211                 },
 212                 {
 213                         &hf_dreg_paging_cycle,
 214                         {
 215                                 "PAGING CYCLE", "wmx.dreg.paging_cycle",
 216                                 FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL
 217                         }
 218                 },
 219                 {
 220                         &hf_dreg_paging_cycle_request,
 221                         {
 222                                 "Paging Cycle Request", "wmx.dreg.paging_cycle_request",
 223                                 FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL
 224                         }
 225                 },
 226                 {
 227                         &hf_dreg_paging_group_id,
 228                         {
 229                                 "Paging-group-ID", "wmx.dreg.paging_group_id",
 230                                 FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL
 231                         }
 232                 },
 233                 {
 234                         &hf_dreg_paging_offset,
 235                         {
 236                                 "PAGING OFFSET", "wmx.dreg.paging_offset",
 237                                 FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL
 238                         }
 239                 },
 240                 {
 241                         &hf_dreg_req_duration,
 242                         {
 243                                 "REQ-duration (Waiting value for the DREG-REQ message re-transmission in frames)", "wmx.dreg.req_duration",
 244                                 FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL
 245                         }
 246                 },
 247                 {
 248                         &hf_dreg_retain_ms_service_full_service,
 249                         {
 250                                 "Retain MS service and operation information associated with Full service", "wmx.dreg.retain_ms_full_service",
 251                                 FT_UINT8, BASE_DEC, NULL, 0x40, NULL, HFILL
 252                         }
 253                 },
 254                 {
 255                         &hf_dreg_retain_ms_service_network_address,
 256                         {
 257                                 "Retain MS service and operational information associated with Network Address", "wmx.dreg.retain_ms_service_network_address",
 258                                 FT_UINT8, BASE_DEC, NULL, 0x08, NULL, HFILL
 259                         }
 260                 },
 261                 {
 262                         &hf_dreg_retain_ms_service_pkm,
 263                         {
 264                                 "Retain MS service and operational information associated with PKM-REQ/RSP", "wmx.dreg.retain_ms_service_pkm",
 265                                 FT_UINT8, BASE_DEC, NULL, 0x02, NULL, HFILL
 266                         }
 267                 },
 268                 {
 269                         &hf_dreg_retain_ms_service_reg,
 270                         {
 271                                 "Retain MS service and operational information associated with REG-REQ/RSP", "wmx.dreg.retain_ms_service_reg",
 272                                 FT_UINT8, BASE_DEC, NULL, 0x04, NULL, HFILL
 273                         }
 274                 },
 275                 {
 276                         &hf_dreg_retain_ms_service_sbc,
 277                         {
 278                                 "Retain MS service and operational information associated with SBC-REQ/RSP", "wmx.dreg.retain_ms_service_sbc",
 279                                 FT_UINT8, BASE_DEC, NULL, 0x01, NULL, HFILL
 280                         }
 281                 },
 282                 {
 283                         &hf_dreg_retain_ms_service_tftp,
 284                         {
 285                                 "Retain MS service and operational information associated with TFTP messages", "wmx.dreg.retain_ms_service_tftp",
 286                                 FT_UINT8, BASE_DEC, NULL, 0x20, NULL, HFILL
 287                         }
 288                 },
 289                 {
 290                         &hf_dreg_retain_ms_service_tod,
 291                         {
 292                                 "Retain MS service and operational information associated with Time of Day", "wmx.dreg.retain_ms_service_tod",
 293                                 FT_UINT8, BASE_DEC, NULL, 0x10, NULL, HFILL
 294                         }
 295                 },
 296                 {
 297                         &hf_dreg_cmd_action,
 298                         {
 299                                 "DREG-CMD Action code", "wmx.dreg_cmd.action",
 300                                 FT_UINT8, BASE_DEC, VALS(vals_dreg_cmd_action), 0x07, NULL, HFILL
 301                         }
 302                 },
 303                 {
 304                         &hf_dreg_cmd_action_cor2,
 305                         {
 306                                 "DREG-CMD Action code", "wmx.dreg_cmd.action",
 307                                 FT_UINT8, BASE_DEC, VALS(vals_dreg_cmd_action_cor2), 0x07, NULL, HFILL
 308                         }
 309                 },
 310                 {
 311                         &hf_dreg_cmd_reserved,
 312                         {
 313                                 "Reserved", "wmx.dreg_cmd.action_reserved",
 314                                 FT_UINT8, BASE_DEC, NULL, 0xF8, NULL, HFILL
 315                         }
 316                 },
 317                 {
 318                         &hf_dreg_req_action,
 319                         {
 320                                 "DREG-REQ Action code", "wmx.dreg_req.action",
 321                                 FT_UINT8, BASE_DEC, VALS(vals_dreg_req_code), 0x03, NULL, HFILL
 322                         }
 323                 },
 324                 {
 325                         &hf_dreg_req_reserved,
 326                         {
 327                                 "Reserved", "wmx.dreg_req.action_reserved",
 328                                 FT_UINT8, BASE_DEC, NULL, 0xFC, NULL, HFILL
 329                         }
 330                 },
 331                 {
 332                         &hf_tlv_value,
 333                         {
 334                                 "Value", "wmx.dreg.unknown_tlv_value",
 335                                 FT_BYTES, BASE_NONE, NULL, 0x00, NULL, HFILL
 336                         }
 337                 },
 338 #if 0
 339                 {
 340                         &hf_ack_type_reserved,
 341                         {
 342                                 "Reserved", "wmx.ack_type_reserved",
 343                                 FT_UINT8, BASE_DEC, NULL, 0x03, NULL, HFILL
 344                         }
 345                 }
 346 #endif
 347         };
 348
 349         proto_mac_mgmt_msg_dreg_req_decoder = proto_register_protocol (
 350                 "WiMax DREG-REQ Messages", /* name */
 351                 "WiMax DREG-REQ", /* short name */
 352                 "wmx.dreg_req" /* abbrev */
 353                 );
 354
 355         proto_register_field_array(proto_mac_mgmt_msg_dreg_req_decoder, hf, array_length(hf));
 356         proto_register_subtree_array(ett, array_length(ett));
 357 }
 358
 359 /* Register Wimax Mac Payload Protocol and Dissector */
 360 void proto_register_mac_mgmt_msg_dreg_cmd(void)
 361 {
 362         proto_mac_mgmt_msg_dreg_cmd_decoder = proto_register_protocol (
 363                 "WiMax DREG-CMD Messages", /* name */
 364                 "WiMax DREG-CMD", /* short name */
 365                 "wmx.dreg_cmd" /* abbrev */
 366                 );
 367 }
 368
 369 /* Decode DREG-REQ messages. */
 370 static void dissect_mac_mgmt_msg_dreg_req_decoder(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 371 {
 372         guint offset = 0;
 373         guint tlv_offset;
 374         guint tvb_len;
 375         proto_item *dreg_req_item;
 376         proto_tree *dreg_req_tree;
 377         proto_tree *tlv_tree = NULL;
 378         tlv_info_t tlv_info;
 379         gint tlv_type;
 380         gint tlv_len;
 381         gboolean hmac_found = FALSE;
 382
 383         {       /* we are being asked for details */
 384
 385                 /* Get the tvb reported length */
 386                 tvb_len =  tvb_reported_length(tvb);
 387                 /* display MAC payload type DREG-REQ */
 388                 dreg_req_item = proto_tree_add_protocol_format(tree, proto_mac_mgmt_msg_dreg_req_decoder, tvb, 0, -1, "MAC Management Message, DREG-REQ");
 389                 /* add MAC DREG REQ subtree */
 390                 dreg_req_tree = proto_item_add_subtree(dreg_req_item, ett_mac_mgmt_msg_dreg_decoder);
 391                 /* display the Action Code */
 392                 proto_tree_add_item(dreg_req_tree, hf_dreg_req_action, tvb, offset, 1, ENC_BIG_ENDIAN);
 393                 /* show the Reserved bits */
 394                 proto_tree_add_item(dreg_req_tree, hf_dreg_req_reserved, tvb, offset, 1, ENC_BIG_ENDIAN);
 395                 offset++;
 396
 397                 while(offset < tvb_len)
 398                 {
 399                         /* Get the TLV data. */
 400                         init_tlv_info(&tlv_info, tvb, offset);
 401                         /* get the TLV type */
 402                         tlv_type = get_tlv_type(&tlv_info);
 403                         /* get the TLV length */
 404                         tlv_len = get_tlv_length(&tlv_info);
 405                         if(tlv_type == -1 || tlv_len > MAX_TLV_LEN || tlv_len < 1)
 406                         {       /* invalid tlv info */
 407                                 col_append_sep_str(pinfo->cinfo, COL_INFO, NULL, "DREG-REQ TLV error");
 408                                 proto_tree_add_item(dreg_req_tree, hf_dreg_invalid_tlv, tvb, offset, (tvb_len - offset), ENC_NA);
 409                                 break;
 410                         }
 411                         /* get the offset to the TLV data */
 412                         tlv_offset = offset + get_tlv_value_offset(&tlv_info);
 413
 414                         switch (tlv_type) {
 415                                 case HMAC_TUPLE:        /* Table 348d */
 416                                         /* decode and display the HMAC Tuple */
 417                                         tlv_tree = add_protocol_subtree(&tlv_info, ett_mac_mgmt_msg_dreg_decoder, dreg_req_tree, proto_mac_mgmt_msg_dreg_req_decoder, tvb, offset, tlv_len, "HMAC Tuple");
 418                                         wimax_hmac_tuple_decoder(tlv_tree, tvb, tlv_offset, tlv_len);
 419                                         hmac_found = TRUE;
 420                                         break;
 421                                 case CMAC_TUPLE:        /* Table 348b */
 422                                         /* decode and display the CMAC Tuple */
 423                                         tlv_tree = add_protocol_subtree(&tlv_info, ett_mac_mgmt_msg_dreg_decoder, dreg_req_tree, proto_mac_mgmt_msg_dreg_req_decoder, tvb, offset, tlv_len, "CMAC Tuple");
 424                                         wimax_cmac_tuple_decoder(tlv_tree, tvb, tlv_offset, tlv_len);
 425                                         break;
 426                                 default:
 427                                         /* Decode DREG-REQ sub-TLV's */
 428                                         tlv_tree = add_protocol_subtree(&tlv_info, ett_mac_mgmt_msg_dreg_decoder, dreg_req_tree, proto_mac_mgmt_msg_dreg_req_decoder, tvb, offset, tlv_len, "DREG-REQ sub-TLV's");
 429                                         dissect_dreg_tlv(tlv_tree, tlv_type, tvb, tlv_offset, tlv_len);
 430                                         break;
 431                         }
 432
 433
 434                         offset = tlv_len + tlv_offset;
 435                 }       /* end of TLV process while loop */
 436                 if (!hmac_found)
 437                         proto_item_append_text(dreg_req_tree, " (HMAC Tuple is missing !)");
 438         }
 439 }
 440
 441 /* Decode DREG-CMD messages. */
 442 static void dissect_mac_mgmt_msg_dreg_cmd_decoder(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 443 {
 444         guint offset = 0;
 445         guint tlv_offset;
 446         guint tvb_len;
 447         proto_item *dreg_cmd_item;
 448         proto_tree *dreg_cmd_tree;
 449         proto_tree *tlv_tree = NULL;
 450         tlv_info_t tlv_info;
 451         gint tlv_type;
 452         gint tlv_len;
 453         gboolean hmac_found = FALSE;
 454
 455         {       /* we are being asked for details */
 456
 457                 /* Get the tvb reported length */
 458                 tvb_len =  tvb_reported_length(tvb);
 459                 /* display MAC payload type DREG-CMD */
 460                 dreg_cmd_item = proto_tree_add_protocol_format(tree, proto_mac_mgmt_msg_dreg_cmd_decoder, tvb, 0, -1, "MAC Management Message, DREG-CMD");
 461                 /* add MAC DREG CMD subtree */
 462                 dreg_cmd_tree = proto_item_add_subtree(dreg_cmd_item, ett_mac_mgmt_msg_dreg_decoder);
 463                 /* display the Action Code */
 464                 if (include_cor2_changes)
 465                         proto_tree_add_item(dreg_cmd_tree, hf_dreg_cmd_action_cor2, tvb, offset, 1, ENC_BIG_ENDIAN);
 466                 else
 467                         proto_tree_add_item(dreg_cmd_tree, hf_dreg_cmd_action, tvb, offset, 1, ENC_BIG_ENDIAN);
 468                 /* show the Reserved bits */
 469                 proto_tree_add_item(dreg_cmd_tree, hf_dreg_cmd_reserved, tvb, offset, 1, ENC_BIG_ENDIAN);
 470                 offset ++;
 471
 472                 while(offset < tvb_len)
 473                 {
 474                         /* Get the TLV data. */
 475                         init_tlv_info(&tlv_info, tvb, offset);
 476                         /* get the TLV type */
 477                         tlv_type = get_tlv_type(&tlv_info);
 478                         /* get the TLV length */
 479                         tlv_len = get_tlv_length(&tlv_info);
 480                         if(tlv_type == -1 || tlv_len > MAX_TLV_LEN || tlv_len < 1)
 481                         {       /* invalid tlv info */
 482                                 col_append_sep_str(pinfo->cinfo, COL_INFO, NULL, "DREG-CMD TLV error");
 483                                 proto_tree_add_item(dreg_cmd_tree, hf_dreg_invalid_tlv, tvb, offset, (tvb_len - offset), ENC_NA);
 484                                 break;
 485                         }
 486                         /* get the offset to the TLV data */
 487                         tlv_offset = offset + get_tlv_value_offset(&tlv_info);
 488
 489                         switch (tlv_type) {
 490                                 case HMAC_TUPLE:        /* Table 348d */
 491                                         /* decode and display the HMAC Tuple */
 492                                         tlv_tree = add_protocol_subtree(&tlv_info, ett_mac_mgmt_msg_dreg_decoder, dreg_cmd_tree, proto_mac_mgmt_msg_dreg_cmd_decoder, tvb, offset, tlv_len, "HMAC Tuple");
 493                                         wimax_hmac_tuple_decoder(tlv_tree, tvb, tlv_offset, tlv_len);
 494                                         hmac_found = TRUE;
 495                                         break;
 496                                 case CMAC_TUPLE:        /* Table 348b */
 497                                         /* decode and display the CMAC Tuple */
 498                                         tlv_tree = add_protocol_subtree(&tlv_info, ett_mac_mgmt_msg_dreg_decoder, dreg_cmd_tree, proto_mac_mgmt_msg_dreg_cmd_decoder, tvb, offset, tlv_len, "CMAC Tuple");
 499                                         wimax_cmac_tuple_decoder(tlv_tree, tvb, tlv_offset, tlv_len);
 500                                         break;
 501                                 default:
 502                                         /* Decode DREG-CMD sub-TLV's */
 503                                         tlv_tree = add_protocol_subtree(&tlv_info, ett_mac_mgmt_msg_dreg_decoder, dreg_cmd_tree, proto_mac_mgmt_msg_dreg_cmd_decoder, tvb, offset, tlv_len, "DREG-CMD sub-TLV's");
 504                                         dissect_dreg_tlv(tlv_tree, tlv_type, tvb, tlv_offset, tlv_len);
 505                                         break;
 506                         }
 507
 508                         offset = tlv_len + tlv_offset;
 509                 }       /* end of TLV process while loop */
 510                 if (!hmac_found)
 511                         proto_item_append_text(dreg_cmd_tree, " (HMAC Tuple is missing !)");
 512         }
 513 }
 514
 515 void
 516 proto_reg_handoff_mac_mgmt_msg_dreg(void)
 517 {
 518         dissector_handle_t dreg_handle;
 519
 520         dreg_handle = create_dissector_handle(dissect_mac_mgmt_msg_dreg_req_decoder, proto_mac_mgmt_msg_dreg_req_decoder);
 521         dissector_add_uint("wmx.mgmtmsg", MAC_MGMT_MSG_DREG_REQ, dreg_handle);
 522
 523         dreg_handle = create_dissector_handle(dissect_mac_mgmt_msg_dreg_cmd_decoder, proto_mac_mgmt_msg_dreg_cmd_decoder);
 524         dissector_add_uint("wmx.mgmtmsg", MAC_MGMT_MSG_DREG_CMD, dreg_handle);
 525 }