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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  27  */
  28
  29 /* Include files */
  30
  31 #ifdef HAVE_CONFIG_H
  32 #include "config.h"
  33 #endif
  34
  35 #include "moduleinfo.h"
  36
  37 #include <glib.h>
  38 #include <epan/packet.h>
  39 #include "crc.h"
  40 #include "wimax_tlv.h"
  41 #include "wimax_mac.h"
  42 #include "wimax_utils.h"
  43
  44 extern gint man_ofdma;
  45 extern  gboolean include_cor2_changes;
  46
  47 /* Forward reference */
  48 static void dissect_dreg_tlv(proto_tree *dreg_tree, gint tlv_type, tvbuff_t *tvb, guint tlv_offset, guint tlv_len);
  49 void dissect_mac_mgmt_msg_dreg_req_decoder(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree);
  50 void dissect_mac_mgmt_msg_dreg_cmd_decoder(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree);
  51
  52 static gint proto_mac_mgmt_msg_dreg_req_decoder = -1;
  53 static gint proto_mac_mgmt_msg_dreg_cmd_decoder = -1;
  54
  55 static gint ett_mac_mgmt_msg_dreg_decoder = -1;
  56
  57 /* Setup protocol subtree array */
  58 static gint *ett[] =
  59 {
  60         &ett_mac_mgmt_msg_dreg_decoder,
  61 };
  62
  63 /* DREG fields */
  64 static gint hf_dreg_cmd_message_type = -1;
  65 static gint hf_dreg_req_message_type = -1;
  66 static gint hf_ack_type_reserved = -1;
  67 static gint hf_dreg_cmd_action = -1;
  68 static gint hf_dreg_cmd_action_cor2 = -1;
  69 static gint hf_dreg_cmd_reserved = -1;
  70 static gint hf_dreg_paging_cycle = -1;
  71 static gint hf_dreg_paging_offset = -1;
  72 static gint hf_dreg_paging_group_id = -1;
  73 static gint hf_dreg_req_duration = -1;
  74 static gint hf_paging_controller_id = -1;
  75 static gint hf_mac_hash_skip_threshold = -1;
  76 static gint hf_dreg_paging_cycle_request = -1;
  77 static gint hf_dreg_retain_ms_service_sbc = -1;
  78 static gint hf_dreg_retain_ms_service_pkm = -1;
  79 static gint hf_dreg_retain_ms_service_reg = -1;
  80 static gint hf_dreg_retain_ms_service_network_address = -1;
  81 static gint hf_dreg_retain_ms_service_tod = -1;
  82 static gint hf_dreg_retain_ms_service_tftp = -1;
  83 static gint hf_dreg_retain_ms_service_full_service = -1;
  84 static gint hf_dreg_consider_paging_pref = -1;
  85 static gint hf_tlv_value = -1;
  86 static gint hf_dreg_req_action = -1;
  87 static gint hf_dreg_req_reserved = -1;
  88 static gint hf_dreg_invalid_tlv = -1;
  89
  90 /* STRING RESOURCES */
  91 static const value_string vals_dreg_req_code[] = {
  92         {0, "SS De-Registration request from BS and network"},
  93         {1, "MS request for De-Registration from serving BS and initiation of Idle Mode"},
  94         {2, "MS response for the Unsolicited De-Registration initiated by BS"},
  95         {3, "Reject for the unsolicited DREG-CMD with action \
  96 code 05 (idle mode request) by the BS.  \
  97 Applicable only when MS has pending UL data to transmit"},
  98         {4, "Reserved"},
  99         {0,                             NULL}
 100 };
 101
 102 static const value_string vals_dreg_cmd_action[] = {
 103         {0, "SS shall immediately terminate service with the BS and \
 104 should attempt network entry at another BS"},
 105         {1, "SS shall listen to the current channel BS but shall not \
 106 transmit until an RES-CMD message or DREG-CMD with \
 107 Action Code 02 or 03 is received"},
 108         {2, "SS shall listen to the BS but only transmit \
 109 on the Basic, and Primary Management Connections"},
 110         {3, "SS shall return to normal operation and may transmit on \
 111 any of its active connections"},
 112         {4, "SS shall terminate current Normal Operations with the BS; \
 113 the BS shall transmit this action code only in response \
 114 to any SS DREG-REQ message"},
 115         {5, "MS shall immediately begin de-registration from serving \
 116 BS and request initiation of MS Idle Mode"},
 117         {6, "The MS may retransmit the DREG-REQ message after the \
 118 time duration (REQ-duration) provided in the message"},
 119         {7, "The MS shall not retransmit the DREG-REQ message and shall \
 120 wait for the DREG-CMD message. BS transmittal of a \
 121 subsequent DREG-CMD with Action Code 03 shall cancel \
 122 this restriction"},
 123         {0,                             NULL}
 124 };
 125
 126 static const value_string vals_dreg_cmd_action_cor2[] = {
 127         {0, "SS shall immediately terminate service with the BS and \
 128 should attempt network entry at another BS"},
 129         {1, "SS shall listen to the current channel BS but shall not \
 130 transmit until an RES-CMD message or DREG-CMD with \
 131 Action Code 02 or 03 is received"},
 132         {2, "SS shall listen to the BS but only transmit \
 133 on the Basic, and Primary Management Connections"},
 134         {3, "SS shall return to normal operation and may transmit on \
 135 any of its active connections"},
 136         {4, "Only valid in response to a DREG-REQ message with DREG \
 137 Code = 00.  SS shall terminate current Normal Operations with the BS"},
 138         {5, "MS shall immediately begin de-registration from serving \
 139 BS and request initiation of MS Idle Mode"},
 140         {6, "Only valid in response to a DREG-REQ message with DREG \
 141 Code = 01.  The MS may retransmit the DREG-REQ message after the \
 142 REQ-duration provided in the message; \
 143 BS sending a subsequent DREG-CMD message with \
 144 Action Code 03 cancels this restriction"},
 145         {0,                             NULL}
 146 };
 147
 148 /* Decode sub-TLV's of either DREG-REQ or DREG-CMD. */
 149 static void dissect_dreg_tlv(proto_tree *dreg_tree, gint tlv_type, tvbuff_t *tvb, guint tlv_offset, guint tlv_len)
 150 {
 151         switch (tlv_type) {
 152                 case DREG_PAGING_INFO:
 153                         proto_tree_add_item(dreg_tree, hf_dreg_paging_cycle, tvb, tlv_offset, 2, ENC_BIG_ENDIAN);
 154                         proto_tree_add_item(dreg_tree, hf_dreg_paging_offset, tvb, tlv_offset + 2, 1, ENC_BIG_ENDIAN);
 155                         proto_tree_add_item(dreg_tree, hf_dreg_paging_group_id, tvb, tlv_offset + 3, 2, ENC_BIG_ENDIAN);
 156                         break;
 157                 case DREG_REQ_DURATION:
 158                         proto_tree_add_item(dreg_tree, hf_dreg_req_duration, tvb, tlv_offset, 1, ENC_BIG_ENDIAN);
 159                         break;
 160                 case DREG_PAGING_CONTROLLER_ID:
 161                         proto_tree_add_item(dreg_tree, hf_paging_controller_id, tvb, tlv_offset, 6, FALSE);
 162                         break;
 163                 case DREG_IDLE_MODE_RETAIN_INFO:
 164                         proto_tree_add_item(dreg_tree, hf_dreg_retain_ms_service_sbc, tvb, tlv_offset, 1, ENC_BIG_ENDIAN);
 165                         proto_tree_add_item(dreg_tree, hf_dreg_retain_ms_service_pkm, tvb, tlv_offset, 1, ENC_BIG_ENDIAN);
 166                         proto_tree_add_item(dreg_tree, hf_dreg_retain_ms_service_reg, tvb, tlv_offset, 1, ENC_BIG_ENDIAN);
 167                         proto_tree_add_item(dreg_tree, hf_dreg_retain_ms_service_network_address, tvb, tlv_offset, 1, ENC_BIG_ENDIAN);
 168                         proto_tree_add_item(dreg_tree, hf_dreg_retain_ms_service_tod, tvb, tlv_offset, 1, ENC_BIG_ENDIAN);
 169                         proto_tree_add_item(dreg_tree, hf_dreg_retain_ms_service_tftp, tvb, tlv_offset, 1, ENC_BIG_ENDIAN);
 170                         proto_tree_add_item(dreg_tree, hf_dreg_retain_ms_service_full_service, tvb, tlv_offset, 1, ENC_BIG_ENDIAN);
 171                         proto_tree_add_item(dreg_tree, hf_dreg_consider_paging_pref, tvb, tlv_offset, 1, ENC_BIG_ENDIAN);
 172                         break;
 173                 case DREG_MAC_HASH_SKIP_THRESHOLD:
 174                         proto_tree_add_item(dreg_tree, hf_mac_hash_skip_threshold, tvb, tlv_offset, 2, ENC_BIG_ENDIAN);
 175                         break;
 176                 case DREG_PAGING_CYCLE_REQUEST:
 177                         proto_tree_add_item(dreg_tree, hf_dreg_paging_cycle_request, tvb, tlv_offset, 2, ENC_BIG_ENDIAN);
 178                         break;
 179                 default:
 180                         proto_tree_add_item(dreg_tree, hf_tlv_value, tvb, tlv_offset, tlv_len, ENC_NA);
 181                         break;
 182         }
 183 }
 184
 185 /* Register Wimax Mac Payload Protocol and Dissector */
 186 void proto_register_mac_mgmt_msg_dreg_req(void)
 187 {
 188         /* DREG fields display */
 189         static hf_register_info hf[] =
 190         {
 191                 {
 192                         &hf_dreg_consider_paging_pref,
 193                         {
 194                                 "Consider Paging Preference of each Service Flow in resource retention", "wmx.dreg.consider_paging_preference",
 195                                 FT_UINT8, BASE_DEC, NULL, 0x80, NULL, HFILL
 196                         }
 197                 },
 198                 {
 199                         &hf_dreg_invalid_tlv,
 200                         {
 201                                 "Invalid TLV", "wmx.dreg.invalid_tlv",
 202                                 FT_BYTES, BASE_NONE, NULL, 0, NULL, HFILL
 203                         }
 204                 },
 205                 {
 206                         &hf_mac_hash_skip_threshold,
 207                         {
 208                                 "MAC Hash Skip Threshold", "wmx.dreg.mac_hash_skip_threshold",
 209                                 FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL
 210                         }
 211                 },
 212                 {
 213                         &hf_paging_controller_id,
 214                         {
 215                                 "Paging Controller ID", "wmx.dreg.paging_controller_id",
 216                                 FT_ETHER, BASE_NONE, NULL, 0x0, NULL, HFILL
 217                         }
 218                 },
 219                 {
 220                         &hf_dreg_paging_cycle,
 221                         {
 222                                 "PAGING CYCLE", "wmx.dreg.paging_cycle",
 223                                 FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL
 224                         }
 225                 },
 226                 {
 227                         &hf_dreg_paging_cycle_request,
 228                         {
 229                                 "Paging Cycle Request", "wmx.dreg.paging_cycle_request",
 230                                 FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL
 231                         }
 232                 },
 233                 {
 234                         &hf_dreg_paging_group_id,
 235                         {
 236                                 "Paging-group-ID", "wmx.dreg.paging_group_id",
 237                                 FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL
 238                         }
 239                 },
 240                 {
 241                         &hf_dreg_paging_offset,
 242                         {
 243                                 "PAGING OFFSET", "wmx.dreg.paging_offset",
 244                                 FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL
 245                         }
 246                 },
 247                 {
 248                         &hf_dreg_req_duration,
 249                         {
 250                                 "REQ-duration (Waiting value for the DREG-REQ message re-transmission in frames)", "wmx.dreg.req_duration",
 251                                 FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL
 252                         }
 253                 },
 254                 {
 255                         &hf_dreg_retain_ms_service_full_service,
 256                         {
 257                                 "Retain MS service and operation information associated with Full service", "wmx.dreg.retain_ms_full_service",
 258                                 FT_UINT8, BASE_DEC, NULL, 0x40, NULL, HFILL
 259                         }
 260                 },
 261                 {
 262                         &hf_dreg_retain_ms_service_network_address,
 263                         {
 264                                 "Retain MS service and operational information associated with Network Address", "wmx.dreg.retain_ms_service_network_address",
 265                                 FT_UINT8, BASE_DEC, NULL, 0x08, NULL, HFILL
 266                         }
 267                 },
 268                 {
 269                         &hf_dreg_retain_ms_service_pkm,
 270                         {
 271                                 "Retain MS service and operational information associated with PKM-REQ/RSP", "wmx.dreg.retain_ms_service_pkm",
 272                                 FT_UINT8, BASE_DEC, NULL, 0x02, NULL, HFILL
 273                         }
 274                 },
 275                 {
 276                         &hf_dreg_retain_ms_service_reg,
 277                         {
 278                                 "Retain MS service and operational information associated with REG-REQ/RSP", "wmx.dreg.retain_ms_service_reg",
 279                                 FT_UINT8, BASE_DEC, NULL, 0x04, NULL, HFILL
 280                         }
 281                 },
 282                 {
 283                         &hf_dreg_retain_ms_service_sbc,
 284                         {
 285                                 "Retain MS service and operational information associated with SBC-REQ/RSP", "wmx.dreg.retain_ms_service_sbc",
 286                                 FT_UINT8, BASE_DEC, NULL, 0x01, NULL, HFILL
 287                         }
 288                 },
 289                 {
 290                         &hf_dreg_retain_ms_service_tftp,
 291                         {
 292                                 "Retain MS service and operational information associated with TFTP messages", "wmx.dreg.retain_ms_service_tftp",
 293                                 FT_UINT8, BASE_DEC, NULL, 0x20, NULL, HFILL
 294                         }
 295                 },
 296                 {
 297                         &hf_dreg_retain_ms_service_tod,
 298                         {
 299                                 "Retain MS service and operational information associated with Time of Day", "wmx.dreg.retain_ms_service_tod",
 300                                 FT_UINT8, BASE_DEC, NULL, 0x10, NULL, HFILL
 301                         }
 302                 },
 303                 {
 304                         &hf_dreg_cmd_message_type,
 305                         {
 306                                 "MAC Management Message Type", "wmx.macmgtmsgtype.dreg_cmd",
 307                                 FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL
 308                         }
 309                 },
 310                 {
 311                         &hf_dreg_cmd_action,
 312                         {
 313                                 "DREG-CMD Action code", "wmx.dreg_cmd.action",
 314                                 FT_UINT8, BASE_DEC, VALS(vals_dreg_cmd_action), 0x07, NULL, HFILL
 315                         }
 316                 },
 317                 {
 318                         &hf_dreg_cmd_action_cor2,
 319                         {
 320                                 "DREG-CMD Action code", "wmx.dreg_cmd.action",
 321                                 FT_UINT8, BASE_DEC, VALS(vals_dreg_cmd_action_cor2), 0x07, NULL, HFILL
 322                         }
 323                 },
 324                 {
 325                         &hf_dreg_cmd_reserved,
 326                         {
 327                                 "Reserved", "wmx.dreg_cmd.action_reserved",
 328                                 FT_UINT8, BASE_DEC, NULL, 0xF8, NULL, HFILL
 329                         }
 330                 },
 331                 {
 332                         &hf_dreg_req_message_type,
 333                         {
 334                                 "MAC Management Message Type", "wmx.macmgtmsgtype.dreg_req",
 335                                 FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL
 336                         }
 337                 },
 338                 {
 339                         &hf_dreg_req_action,
 340                         {
 341                                 "DREG-REQ Action code", "wmx.dreg_req.action",
 342                                 FT_UINT8, BASE_DEC, VALS(vals_dreg_req_code), 0x03, NULL, HFILL
 343                         }
 344                 },
 345                 {
 346                         &hf_dreg_req_reserved,
 347                         {
 348                                 "Reserved", "wmx.dreg_req.action_reserved",
 349                                 FT_UINT8, BASE_DEC, NULL, 0xFC, NULL, HFILL
 350                         }
 351                 },
 352                 {
 353                         &hf_tlv_value,
 354                         {
 355                                 "Value", "wmx.dreg.unknown_tlv_value",
 356                                 FT_BYTES, BASE_NONE, NULL, 0x00, NULL, HFILL
 357                         }
 358                 },
 359                 {
 360                         &hf_ack_type_reserved,
 361                         {
 362                                 "Reserved", "wmx.ack_type_reserved",
 363                                 FT_UINT8, BASE_DEC, NULL, 0x03, NULL, HFILL
 364                         }
 365                 }
 366         };
 367
 368         proto_mac_mgmt_msg_dreg_req_decoder = proto_register_protocol (
 369                 "WiMax DREG-REQ/CMD Messages", /* name */
 370                 "WiMax DREG-REQ/CMD (dreg)", /* short name */
 371                 "wmx.dreg" /* abbrev */
 372                 );
 373
 374         proto_register_field_array(proto_mac_mgmt_msg_dreg_req_decoder, hf, array_length(hf));
 375         proto_register_subtree_array(ett, array_length(ett));
 376 }
 377
 378 /* Register Wimax Mac Payload Protocol and Dissector */
 379 void proto_register_mac_mgmt_msg_dreg_cmd(void)
 380 {
 381         proto_mac_mgmt_msg_dreg_cmd_decoder = proto_mac_mgmt_msg_dreg_req_decoder;
 382 }
 383
 384 /* Decode DREG-REQ messages. */
 385 void dissect_mac_mgmt_msg_dreg_req_decoder(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 386 {
 387         guint offset = 0;
 388         guint tlv_offset;
 389         guint tvb_len, payload_type;
 390         proto_item *dreg_req_item = NULL;
 391         proto_tree *dreg_req_tree = NULL;
 392         proto_tree *tlv_tree = NULL;
 393         tlv_info_t tlv_info;
 394         gint tlv_type;
 395         gint tlv_len;
 396         gboolean hmac_found = FALSE;
 397
 398         /* Ensure the right payload type */
 399         payload_type = tvb_get_guint8(tvb, 0);
 400         if(payload_type != MAC_MGMT_MSG_DREG_REQ)
 401         {
 402                 return;
 403         }
 404
 405         if (tree)
 406         {       /* we are being asked for details */
 407
 408                 /* Get the tvb reported length */
 409                 tvb_len =  tvb_reported_length(tvb);
 410                 /* display MAC payload type DREG-REQ */
 411                 dreg_req_item = proto_tree_add_protocol_format(tree, proto_mac_mgmt_msg_dreg_req_decoder, tvb, 0, tvb_len, "MAC Management Message, DREG-REQ (49)");
 412                 /* add MAC DREG REQ subtree */
 413                 dreg_req_tree = proto_item_add_subtree(dreg_req_item, ett_mac_mgmt_msg_dreg_decoder);
 414                 /* display the Message Type */
 415                 proto_tree_add_item(dreg_req_tree, hf_dreg_req_message_type, tvb, offset, 1, ENC_BIG_ENDIAN);
 416                 offset++;
 417                 /* display the Action Code */
 418                 proto_tree_add_item(dreg_req_tree, hf_dreg_req_action, tvb, offset, 1, ENC_BIG_ENDIAN);
 419                 /* show the Reserved bits */
 420                 proto_tree_add_item(dreg_req_tree, hf_dreg_req_reserved, tvb, offset, 1, ENC_BIG_ENDIAN);
 421                 offset++;
 422
 423                 while(offset < tvb_len)
 424                 {
 425                         /* Get the TLV data. */
 426                         init_tlv_info(&tlv_info, tvb, offset);
 427                         /* get the TLV type */
 428                         tlv_type = get_tlv_type(&tlv_info);
 429                         /* get the TLV length */
 430                         tlv_len = get_tlv_length(&tlv_info);
 431                         if(tlv_type == -1 || tlv_len > MAX_TLV_LEN || tlv_len < 1)
 432                         {       /* invalid tlv info */
 433                                 col_append_sep_str(pinfo->cinfo, COL_INFO, NULL, "DREG-REQ TLV error");
 434                                 proto_tree_add_item(dreg_req_tree, hf_dreg_invalid_tlv, tvb, offset, (tvb_len - offset), ENC_NA);
 435                                 break;
 436                         }
 437                         /* get the offset to the TLV data */
 438                         tlv_offset = offset + get_tlv_value_offset(&tlv_info);
 439
 440                         switch (tlv_type) {
 441                                 case HMAC_TUPLE:        /* Table 348d */
 442                                         /* decode and display the HMAC Tuple */
 443                                         tlv_tree = add_protocol_subtree(&tlv_info, ett_mac_mgmt_msg_dreg_decoder, dreg_req_tree, proto_mac_mgmt_msg_dreg_req_decoder, tvb, tlv_offset, tlv_len, "HMAC Tuple (%u byte(s))", tlv_len);
 444                                         wimax_hmac_tuple_decoder(tlv_tree, tvb, tlv_offset, tlv_len);
 445                                         hmac_found = TRUE;
 446                                         break;
 447                                 case CMAC_TUPLE:        /* Table 348b */
 448                                         /* decode and display the CMAC Tuple */
 449                                         tlv_tree = add_protocol_subtree(&tlv_info, ett_mac_mgmt_msg_dreg_decoder, dreg_req_tree, proto_mac_mgmt_msg_dreg_req_decoder, tvb, tlv_offset, tlv_len, "CMAC Tuple (%u byte(s))", tlv_len);
 450                                         wimax_cmac_tuple_decoder(tlv_tree, tvb, tlv_offset, tlv_len);
 451                                         break;
 452                                 default:
 453                                         /* Decode DREG-REQ sub-TLV's */
 454                                         tlv_tree = add_protocol_subtree(&tlv_info, ett_mac_mgmt_msg_dreg_decoder, dreg_req_tree, proto_mac_mgmt_msg_dreg_req_decoder, tvb, tlv_offset, tlv_len, "DREG-REQ sub-TLV's (%u byte(s))", tlv_len);
 455                                         dissect_dreg_tlv(tlv_tree, tlv_type, tvb, tlv_offset, tlv_len);
 456                                         break;
 457                         }
 458
 459
 460                         offset = tlv_len + tlv_offset;
 461                 }       /* end of TLV process while loop */
 462                 if (!hmac_found)
 463                         proto_item_append_text(dreg_req_tree, " (HMAC Tuple is missing !)");
 464         }
 465 }
 466
 467 /* Decode DREG-CMD messages. */
 468 void dissect_mac_mgmt_msg_dreg_cmd_decoder(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 469 {
 470         guint offset = 0;
 471         guint tlv_offset;
 472         guint tvb_len, payload_type;
 473         proto_item *dreg_cmd_item = NULL;
 474         proto_tree *dreg_cmd_tree = NULL;
 475         proto_tree *tlv_tree = NULL;
 476         tlv_info_t tlv_info;
 477         gint tlv_type;
 478         gint tlv_len;
 479         gboolean hmac_found = FALSE;
 480
 481         /* Ensure the right payload type */
 482         payload_type = tvb_get_guint8(tvb, 0);
 483         if(payload_type != MAC_MGMT_MSG_DREG_CMD)
 484         {
 485                 return;
 486         }
 487
 488         if (tree)
 489         {       /* we are being asked for details */
 490
 491                 /* Get the tvb reported length */
 492                 tvb_len =  tvb_reported_length(tvb);
 493                 /* display MAC payload type DREG-CMD */
 494                 dreg_cmd_item = proto_tree_add_protocol_format(tree, proto_mac_mgmt_msg_dreg_cmd_decoder, tvb, 0, tvb_len, "MAC Management Message, DREG-CMD (29)");
 495                 /* add MAC DREG CMD subtree */
 496                 dreg_cmd_tree = proto_item_add_subtree(dreg_cmd_item, ett_mac_mgmt_msg_dreg_decoder);
 497                 /* display the Message Type */
 498                 proto_tree_add_item(dreg_cmd_tree, hf_dreg_cmd_message_type, tvb, offset, 1, ENC_BIG_ENDIAN);
 499                 offset ++;
 500                 /* display the Action Code */
 501                 if (include_cor2_changes)
 502                         proto_tree_add_item(dreg_cmd_tree, hf_dreg_cmd_action_cor2, tvb, offset, 1, ENC_BIG_ENDIAN);
 503                 else
 504                         proto_tree_add_item(dreg_cmd_tree, hf_dreg_cmd_action, tvb, offset, 1, ENC_BIG_ENDIAN);
 505                 /* show the Reserved bits */
 506                 proto_tree_add_item(dreg_cmd_tree, hf_dreg_cmd_reserved, tvb, offset, 1, ENC_BIG_ENDIAN);
 507                 offset ++;
 508
 509                 while(offset < tvb_len)
 510                 {
 511                         /* Get the TLV data. */
 512                         init_tlv_info(&tlv_info, tvb, offset);
 513                         /* get the TLV type */
 514                         tlv_type = get_tlv_type(&tlv_info);
 515                         /* get the TLV length */
 516                         tlv_len = get_tlv_length(&tlv_info);
 517                         if(tlv_type == -1 || tlv_len > MAX_TLV_LEN || tlv_len < 1)
 518                         {       /* invalid tlv info */
 519                                 col_append_sep_str(pinfo->cinfo, COL_INFO, NULL, "DREG-CMD TLV error");
 520                                 proto_tree_add_item(dreg_cmd_tree, hf_dreg_invalid_tlv, tvb, offset, (tvb_len - offset), ENC_NA);
 521                                 break;
 522                         }
 523                         /* get the offset to the TLV data */
 524                         tlv_offset = offset + get_tlv_value_offset(&tlv_info);
 525
 526                         switch (tlv_type) {
 527                                 case HMAC_TUPLE:        /* Table 348d */
 528                                         /* decode and display the HMAC Tuple */
 529                                         tlv_tree = add_protocol_subtree(&tlv_info, ett_mac_mgmt_msg_dreg_decoder, dreg_cmd_tree, proto_mac_mgmt_msg_dreg_cmd_decoder, tvb, tlv_offset, tlv_len, "HMAC Tuple (%u byte(s))", tlv_len);
 530                                         wimax_hmac_tuple_decoder(tlv_tree, tvb, tlv_offset, tlv_len);
 531                                         hmac_found = TRUE;
 532                                         break;
 533                                 case CMAC_TUPLE:        /* Table 348b */
 534                                         /* decode and display the CMAC Tuple */
 535                                         tlv_tree = add_protocol_subtree(&tlv_info, ett_mac_mgmt_msg_dreg_decoder, dreg_cmd_tree, proto_mac_mgmt_msg_dreg_cmd_decoder, tvb, tlv_offset, tlv_len, "CMAC Tuple (%u byte(s))", tlv_len);
 536                                         wimax_cmac_tuple_decoder(tlv_tree, tvb, tlv_offset, tlv_len);
 537                                         break;
 538                                 default:
 539                                         /* Decode DREG-CMD sub-TLV's */
 540                                         tlv_tree = add_protocol_subtree(&tlv_info, ett_mac_mgmt_msg_dreg_decoder, dreg_cmd_tree, proto_mac_mgmt_msg_dreg_cmd_decoder, tvb, tlv_offset, tlv_len, "DREG-CMD sub-TLV's (%u byte(s))", tlv_len);
 541                                         dissect_dreg_tlv(tlv_tree, tlv_type, tvb, tlv_offset, tlv_len);
 542                                         break;
 543                         }
 544
 545                         offset = tlv_len + tlv_offset;
 546                 }       /* end of TLV process while loop */
 547                 if (!hmac_found)
 548                         proto_item_append_text(dreg_cmd_tree, " (HMAC Tuple is missing !)");
 549         }
 550 }
 551