epan/dissectors/packet-pptp.c

   1 /* packet-pptp.c
   2  * Routines for the Point-to-Point Tunnelling Protocol (PPTP) (RFC 2637)
   3  * Brad Robel-Forrest <brad.robel-forrest@watchguard.com>
   4  *
   5  * 10/2010 - Rework PPTP Dissector
   6  * Alexis La Goutte <alexis.lagoutte at gmail dot com>
   7  *
   8  * $Id$
   9  *
  10  * Wireshark - Network traffic analyzer
  11  * By Gerald Combs <gerald@wireshark.org>
  12  * Copyright 1998 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 "config.h"
  30
  31 #include <glib.h>
  32 #include <epan/packet.h>
  33 #include <epan/expert.h>
  34
  35 static int proto_pptp = -1;
  36 static int hf_pptp_length = -1;
  37 static int hf_pptp_message_type = -1;
  38 static int hf_pptp_magic_cookie = -1;
  39 static int hf_pptp_control_message_type = -1;
  40 static int hf_pptp_reserved = -1;
  41 static int hf_pptp_protocol_version = -1;
  42 static int hf_pptp_framing_capabilities = -1;
  43 static int hf_pptp_bearer_capabilities = -1;
  44 static int hf_pptp_maximum_channels = -1;
  45 static int hf_pptp_firmware_revision = -1;
  46 static int hf_pptp_host_name = -1;
  47 static int hf_pptp_vendor_name = -1;
  48 static int hf_pptp_control_result = -1;
  49 static int hf_pptp_error = -1;
  50 static int hf_pptp_reason = -1;
  51 static int hf_pptp_stop_result = -1;
  52 static int hf_pptp_identifier = -1;
  53 static int hf_pptp_echo_result = -1;
  54 static int hf_pptp_call_id = -1;
  55 static int hf_pptp_call_serial_number = -1;
  56 static int hf_pptp_minimum_bps = -1;
  57 static int hf_pptp_maximum_bps = -1;
  58 static int hf_pptp_bearer_type = -1;
  59 static int hf_pptp_framing_type = -1;
  60 static int hf_pptp_packet_receive_window_size = -1;
  61 static int hf_pptp_packet_processing_delay = -1;
  62 static int hf_pptp_phone_number_length = -1;
  63 static int hf_pptp_phone_number = -1;
  64 static int hf_pptp_subaddress = -1;
  65 static int hf_pptp_peer_call_id = -1;
  66 static int hf_pptp_out_result = -1;
  67 static int hf_pptp_cause = -1;
  68 static int hf_pptp_connect_speed = -1;
  69 static int hf_pptp_physical_channel_id = -1;
  70 static int hf_pptp_dialed_number_length = -1;
  71 static int hf_pptp_dialed_number = -1;
  72 static int hf_pptp_dialing_number_length = -1;
  73 static int hf_pptp_dialing_number = -1;
  74 static int hf_pptp_in_result = -1;
  75 static int hf_pptp_disc_result = -1;
  76 static int hf_pptp_call_statistics = -1;
  77 static int hf_pptp_crc_errors = -1;
  78 static int hf_pptp_framing_errors = -1;
  79 static int hf_pptp_hardware_overruns = -1;
  80 static int hf_pptp_buffer_overruns = -1;
  81 static int hf_pptp_timeout_errors = -1;
  82 static int hf_pptp_alignment_errors = -1;
  83 static int hf_pptp_send_accm = -1;
  84 static int hf_pptp_receive_accm = -1;
  85
  86 static gint ett_pptp = -1;
  87
  88 static expert_field ei_pptp_incorrect_magic_cookie = EI_INIT;
  89
  90 static dissector_handle_t data_handle;
  91
  92 #define TCP_PORT_PPTP           1723
  93
  94 #define MAGIC_COOKIE            0x1A2B3C4D
  95
  96 #define CNTRL_REQ       0x01
  97 #define CNTRL_REPLY     0x02
  98 #define STOP_REQ        0x03
  99 #define STOP_REPLY      0x04
 100 #define ECHO_REQ        0x05
 101 #define ECHO_REPLY      0x06
 102 #define OUT_REQ         0x07
 103 #define OUT_REPLY       0x08
 104 #define IN_REQ          0x09
 105 #define IN_REPLY        0x0A
 106 #define IN_CONNECTED    0x0B
 107 #define CLEAR_REQ       0x0C
 108 #define DISC_NOTIFY     0x0D
 109 #define ERROR_NOTIFY    0x0E
 110 #define SET_LINK        0x0F
 111
 112 static const value_string control_message_type_vals[] = {
 113   { CNTRL_REQ,    "Start-Control-Connection-Request" },
 114   { CNTRL_REPLY,  "Start-Control-Connection-Reply" },
 115   { STOP_REQ,     "Stop-Control-Connection-Request" },
 116   { STOP_REPLY,   "Stop-Control-Connection-Reply" },
 117   { ECHO_REQ,     "Echo-Request" },
 118   { ECHO_REPLY,   "Echo-Reply" },
 119   { OUT_REQ,      "Outgoing-Call-Request" },
 120   { OUT_REPLY,    "Outgoing-Call-Reply" },
 121   { IN_REQ,       "Incoming-Call-Request" },
 122   { IN_REPLY,     "Incoming-Call-Reply" },
 123   { IN_CONNECTED, "Incoming-Call-Connected" },
 124   { CLEAR_REQ,    "Call-Clear-Request" },
 125   { DISC_NOTIFY,  "Call-Disconnect-Notify" },
 126   { ERROR_NOTIFY, "WAN-Error-Notify" },
 127   { SET_LINK,     "Set-Link-Info" },
 128   { 0,  NULL },
 129 };
 130 static const value_string msgtype_vals[] = {
 131   { 1, "Control Message" },
 132   { 2, "Management Message" },
 133   { 0, NULL }
 134 };
 135
 136 static const value_string frametype_vals[] = {
 137   { 1, "Asynchronous Framing supported" },
 138   { 2, "Synchronous Framing supported"},
 139   { 3, "Either Framing supported" },
 140   { 0, NULL }
 141 };
 142
 143 static const value_string bearertype_vals[] = {
 144   { 1, "Analog access supported" },
 145   { 2, "Digital access supported" },
 146   { 3, "Either access supported" },
 147   { 0, NULL }
 148 };
 149
 150 static const value_string control_resulttype_vals[] = {
 151   { 1, "Successful channel establishment" },
 152   { 2, "General error" },
 153   { 3, "Command channel already exists" },
 154   { 4, "Requester not authorized" },
 155   { 5, "Protocol version not supported" },
 156   { 0, NULL }
 157 };
 158
 159 static const value_string errortype_vals[] = {
 160   { 0, "None" },
 161   { 1, "Not-Connected" },
 162   { 2, "Bad-Format" },
 163   { 3, "Bad-Value" },
 164   { 4, "No-Resource" },
 165   { 5, "Bad-Call ID" },
 166   { 6, "PAC-Error" },
 167   { 0, NULL }
 168 };
 169
 170 static const value_string reasontype_vals[] = {
 171   { 1, "None" },
 172   { 2, "Stop-Protocol" },
 173   { 3, "Stop-Local-Shutdown" },
 174   { 0, NULL }
 175 };
 176
 177 static const value_string stop_resulttype_vals[] = {
 178   { 1, "OK" },
 179   { 2, "General error" },
 180   { 0, NULL }
 181 };
 182
 183 static const value_string echo_resulttype_vals[] = {
 184   { 1, "OK" },
 185   { 2, "General error" },
 186   { 0, NULL }
 187 };
 188
 189 static const value_string out_resulttype_vals[] = {
 190   { 1, "Connected" },
 191   { 2, "General Error" },
 192   { 3, "No Carrier" },
 193   { 4, "Busy" },
 194   { 5, "No Dial Tone" },
 195   { 6, "Time-out" },
 196   { 7, "Do Not Accept" },
 197   { 0, NULL }
 198 };
 199
 200 static const value_string in_resulttype_vals[] = {
 201   { 1, "Connect" },
 202   { 2, "General error" },
 203   { 3, "Do Not Accept" },
 204   { 0, NULL }
 205 };
 206
 207 static const value_string disc_resulttype_vals[] = {
 208   { 1, "Lost Carrier" },
 209   { 2, "General Error" },
 210   { 3, "Admin Shutdown" },
 211   { 4, "Request" },
 212   { 0, NULL }
 213 };
 214
 215 static void
 216 dissect_unknown(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree)
 217 {
 218   call_dissector(data_handle,tvb_new_subset_remaining(tvb, offset), pinfo, tree);
 219 }
 220
 221 static void
 222 dissect_cntrl_req(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree)
 223 {
 224   if (!tree)
 225     return;
 226
 227   proto_tree_add_uint_format_value(tree, hf_pptp_protocol_version, tvb, offset,
 228                                2, tvb_get_ntohs(tvb, offset), "%u.%u",
 229                                tvb_get_guint8(tvb, offset), tvb_get_guint8(tvb, offset + 1));
 230   offset += 2;
 231
 232   proto_tree_add_item(tree, hf_pptp_reserved,             tvb, offset, 2, ENC_NA);
 233   offset += 2;
 234
 235   proto_tree_add_item(tree, hf_pptp_framing_capabilities, tvb, offset, 4, ENC_BIG_ENDIAN);
 236   offset += 4;
 237
 238   proto_tree_add_item(tree, hf_pptp_bearer_capabilities,  tvb, offset, 4, ENC_BIG_ENDIAN);
 239   offset += 4;
 240
 241   proto_tree_add_item(tree, hf_pptp_maximum_channels,     tvb, offset, 2, ENC_BIG_ENDIAN);
 242   offset += 2;
 243
 244   proto_tree_add_item(tree, hf_pptp_firmware_revision,    tvb, offset, 2, ENC_BIG_ENDIAN);
 245   offset += 2;
 246
 247   proto_tree_add_item(tree, hf_pptp_host_name,            tvb, offset, 64, ENC_ASCII|ENC_NA);
 248   offset += 64;
 249
 250   proto_tree_add_item(tree, hf_pptp_vendor_name,          tvb, offset, 64, ENC_ASCII|ENC_NA);
 251 }
 252
 253 static void
 254 dissect_cntrl_reply(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree)
 255 {
 256   if (!tree)
 257     return;
 258
 259   proto_tree_add_uint_format_value(tree, hf_pptp_protocol_version, tvb, offset,
 260                                2, tvb_get_ntohs(tvb, offset), "%u.%u",
 261                                tvb_get_guint8(tvb, offset), tvb_get_guint8(tvb, offset + 1));
 262   offset += 2;
 263
 264   proto_tree_add_item(tree, hf_pptp_control_result,       tvb, offset, 1, ENC_BIG_ENDIAN);
 265   offset += 1;
 266
 267   proto_tree_add_item(tree, hf_pptp_error,                tvb, offset, 1, ENC_BIG_ENDIAN);
 268   offset += 1;
 269
 270   proto_tree_add_item(tree, hf_pptp_framing_capabilities, tvb, offset, 4, ENC_BIG_ENDIAN);
 271   offset += 4;
 272
 273   proto_tree_add_item(tree, hf_pptp_bearer_capabilities,  tvb, offset, 4, ENC_BIG_ENDIAN);
 274   offset += 4;
 275
 276   proto_tree_add_item(tree, hf_pptp_maximum_channels,     tvb, offset, 2, ENC_BIG_ENDIAN);
 277   offset += 2;
 278
 279   proto_tree_add_item(tree, hf_pptp_firmware_revision,    tvb, offset, 2, ENC_BIG_ENDIAN);
 280   offset += 2;
 281
 282   proto_tree_add_item(tree, hf_pptp_host_name,            tvb, offset, 64, ENC_ASCII|ENC_NA);
 283   offset += 64;
 284
 285   proto_tree_add_item(tree, hf_pptp_vendor_name,          tvb, offset, 64, ENC_ASCII|ENC_NA);
 286
 287 }
 288
 289 static void
 290 dissect_stop_req(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree)
 291 {
 292   if (!tree)
 293     return;
 294
 295   proto_tree_add_item(tree, hf_pptp_reason,   tvb, offset, 1, ENC_BIG_ENDIAN);
 296   offset += 1;
 297
 298   proto_tree_add_item(tree, hf_pptp_reserved, tvb, offset, 1, ENC_NA);
 299   offset += 1;
 300
 301   proto_tree_add_item(tree, hf_pptp_reserved, tvb, offset, 2, ENC_NA);
 302 }
 303
 304 static void
 305 dissect_stop_reply(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree)
 306 {
 307   if (!tree)
 308     return;
 309
 310   proto_tree_add_item(tree, hf_pptp_stop_result, tvb, offset, 1, ENC_BIG_ENDIAN);
 311   offset += 1;
 312
 313   proto_tree_add_item(tree, hf_pptp_error,       tvb, offset, 1, ENC_BIG_ENDIAN);
 314   offset += 1;
 315
 316   proto_tree_add_item(tree, hf_pptp_reserved,    tvb, offset, 2, ENC_NA);
 317
 318 }
 319
 320 static void
 321 dissect_echo_req(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree)
 322 {
 323   if (!tree)
 324     return;
 325
 326   proto_tree_add_item(tree, hf_pptp_identifier, tvb, offset, 4, ENC_BIG_ENDIAN);
 327 }
 328
 329 static void
 330 dissect_echo_reply(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree)
 331 {
 332   if (!tree)
 333     return;
 334
 335   proto_tree_add_item(tree, hf_pptp_identifier,  tvb, offset, 4, ENC_BIG_ENDIAN);
 336   offset += 4;
 337
 338   proto_tree_add_item(tree, hf_pptp_echo_result, tvb, offset, 1, ENC_BIG_ENDIAN);
 339   offset += 1;
 340
 341   proto_tree_add_item(tree, hf_pptp_error,       tvb, offset, 1, ENC_BIG_ENDIAN);
 342   offset += 1;
 343
 344   proto_tree_add_item(tree, hf_pptp_reserved,    tvb, offset, 2, ENC_NA);
 345 }
 346
 347 static void
 348 dissect_out_req(tvbuff_t *tvb, int offset, packet_info *pinfo _U_,      proto_tree *tree)
 349 {
 350   if (!tree)
 351     return;
 352
 353   proto_tree_add_item(tree, hf_pptp_call_id,                    tvb, offset, 2, ENC_BIG_ENDIAN);
 354   offset += 2;
 355
 356   proto_tree_add_item(tree, hf_pptp_call_serial_number,         tvb, offset, 2, ENC_BIG_ENDIAN);
 357   offset += 2;
 358
 359   proto_tree_add_item(tree, hf_pptp_minimum_bps,                tvb, offset, 4, ENC_BIG_ENDIAN);
 360   offset += 4;
 361
 362   proto_tree_add_item(tree, hf_pptp_maximum_bps,                tvb, offset, 4, ENC_BIG_ENDIAN);
 363   offset += 4;
 364
 365   proto_tree_add_item(tree, hf_pptp_bearer_type,                tvb, offset, 4, ENC_BIG_ENDIAN);
 366   offset += 4;
 367
 368   proto_tree_add_item(tree, hf_pptp_framing_type,               tvb, offset, 4, ENC_BIG_ENDIAN);
 369   offset += 4;
 370
 371   proto_tree_add_item(tree, hf_pptp_packet_receive_window_size, tvb, offset, 2, ENC_BIG_ENDIAN);
 372   offset += 2;
 373
 374   proto_tree_add_item(tree, hf_pptp_packet_processing_delay,    tvb, offset, 2, ENC_BIG_ENDIAN);
 375   offset += 2;
 376
 377   proto_tree_add_item(tree, hf_pptp_phone_number_length,        tvb, offset, 2, ENC_BIG_ENDIAN);
 378   offset += 2;
 379
 380   proto_tree_add_item(tree, hf_pptp_reserved,                   tvb, offset, 2, ENC_NA);
 381   offset += 2;
 382
 383   proto_tree_add_item(tree, hf_pptp_phone_number,               tvb, offset, 64, ENC_ASCII|ENC_NA);
 384   offset += 64;
 385
 386   proto_tree_add_item(tree, hf_pptp_subaddress,                 tvb, offset, 64, ENC_ASCII|ENC_NA);
 387 }
 388
 389 static void
 390 dissect_out_reply(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree)
 391 {
 392   if (!tree)
 393     return;
 394
 395   proto_tree_add_item(tree, hf_pptp_call_id,                    tvb, offset, 2, ENC_BIG_ENDIAN);
 396   offset += 2;
 397
 398   proto_tree_add_item(tree, hf_pptp_peer_call_id,               tvb, offset, 2, ENC_BIG_ENDIAN);
 399   offset += 2;
 400
 401   proto_tree_add_item(tree, hf_pptp_out_result,                 tvb, offset, 1, ENC_BIG_ENDIAN);
 402   offset += 1;
 403
 404   proto_tree_add_item(tree, hf_pptp_error,                      tvb, offset, 1, ENC_BIG_ENDIAN);
 405   offset += 1;
 406
 407   proto_tree_add_item(tree, hf_pptp_cause,                      tvb, offset, 2, ENC_BIG_ENDIAN);
 408   offset += 2;
 409
 410   proto_tree_add_item(tree, hf_pptp_connect_speed,              tvb, offset, 4, ENC_BIG_ENDIAN);
 411   offset += 4;
 412
 413   proto_tree_add_item(tree, hf_pptp_packet_receive_window_size, tvb, offset, 2, ENC_BIG_ENDIAN);
 414   offset += 2;
 415
 416   proto_tree_add_item(tree, hf_pptp_packet_processing_delay,    tvb, offset, 2, ENC_BIG_ENDIAN);
 417   offset += 2;
 418
 419   proto_tree_add_item(tree, hf_pptp_physical_channel_id,        tvb, offset, 4, ENC_BIG_ENDIAN);
 420 }
 421
 422 static void
 423 dissect_in_req(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree)
 424 {
 425   if (!tree)
 426     return;
 427
 428   proto_tree_add_item(tree, hf_pptp_call_id,               tvb, offset, 2, ENC_BIG_ENDIAN);
 429   offset += 2;
 430
 431   proto_tree_add_item(tree, hf_pptp_call_serial_number,    tvb, offset, 2, ENC_BIG_ENDIAN);
 432   offset += 2;
 433
 434   proto_tree_add_item(tree, hf_pptp_bearer_type,           tvb, offset, 4, ENC_BIG_ENDIAN);
 435   offset += 4;
 436
 437   proto_tree_add_item(tree, hf_pptp_physical_channel_id,   tvb, offset, 4, ENC_BIG_ENDIAN);
 438   offset += 4;
 439
 440   proto_tree_add_item(tree, hf_pptp_dialed_number_length,  tvb, offset, 2, ENC_BIG_ENDIAN);
 441   offset += 2;
 442
 443   proto_tree_add_item(tree, hf_pptp_dialing_number_length, tvb, offset, 2, ENC_BIG_ENDIAN);
 444   offset += 2;
 445
 446   proto_tree_add_item(tree, hf_pptp_dialed_number,         tvb, offset, 64, ENC_ASCII|ENC_NA);
 447   offset += 64;
 448
 449   proto_tree_add_item(tree, hf_pptp_dialing_number,        tvb, offset, 64, ENC_ASCII|ENC_NA);
 450   offset += 64;
 451
 452   proto_tree_add_item(tree, hf_pptp_subaddress,            tvb, offset, 64, ENC_ASCII|ENC_NA);
 453 }
 454
 455 static void
 456 dissect_in_reply(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree)
 457 {
 458   if (!tree)
 459     return;
 460
 461   proto_tree_add_item(tree, hf_pptp_call_id,                    tvb, offset, 2, ENC_BIG_ENDIAN);
 462   offset += 2;
 463
 464   proto_tree_add_item(tree, hf_pptp_peer_call_id,               tvb, offset, 2, ENC_BIG_ENDIAN);
 465   offset += 2;
 466
 467   proto_tree_add_item(tree, hf_pptp_in_result,                  tvb, offset, 1, ENC_BIG_ENDIAN);
 468   offset += 1;
 469
 470   proto_tree_add_item(tree, hf_pptp_error,                      tvb, offset, 1, ENC_BIG_ENDIAN);
 471   offset += 1;
 472
 473   proto_tree_add_item(tree, hf_pptp_packet_receive_window_size, tvb, offset, 2, ENC_BIG_ENDIAN);
 474   offset += 2;
 475
 476   proto_tree_add_item(tree, hf_pptp_packet_processing_delay,    tvb, offset, 2, ENC_BIG_ENDIAN);
 477   offset += 2;
 478
 479   proto_tree_add_item(tree, hf_pptp_reserved,                   tvb, offset, 2, ENC_NA);
 480 }
 481
 482 static void
 483 dissect_in_connected(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree)
 484 {
 485   if (!tree)
 486     return;
 487
 488   proto_tree_add_item(tree, hf_pptp_peer_call_id,               tvb, offset, 2, ENC_BIG_ENDIAN);
 489   offset += 2;
 490
 491   proto_tree_add_item(tree, hf_pptp_reserved,                   tvb, offset, 2, ENC_NA);
 492   offset += 2;
 493
 494   proto_tree_add_item(tree, hf_pptp_connect_speed,              tvb, offset, 4, ENC_BIG_ENDIAN);
 495   offset += 4;
 496
 497   proto_tree_add_item(tree, hf_pptp_packet_receive_window_size, tvb, offset, 2, ENC_BIG_ENDIAN);
 498   offset += 2;
 499
 500   proto_tree_add_item(tree, hf_pptp_packet_processing_delay,    tvb, offset, 2, ENC_BIG_ENDIAN);
 501   offset += 2;
 502
 503   proto_tree_add_item(tree, hf_pptp_framing_type,               tvb, offset, 4, ENC_BIG_ENDIAN);
 504 }
 505
 506 static void
 507 dissect_clear_req(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree)
 508 {
 509   if (!tree)
 510     return;
 511
 512   proto_tree_add_item(tree, hf_pptp_call_id,  tvb, offset, 2, ENC_BIG_ENDIAN);
 513   offset += 2;
 514
 515   proto_tree_add_item(tree, hf_pptp_reserved, tvb, offset, 2, ENC_NA);
 516 }
 517
 518 static void
 519 dissect_disc_notify(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree)
 520 {
 521   if (!tree)
 522     return;
 523
 524   proto_tree_add_item(tree, hf_pptp_call_id,         tvb, offset, 2, ENC_BIG_ENDIAN);
 525   offset += 2;
 526
 527   proto_tree_add_item(tree, hf_pptp_disc_result,     tvb, offset, 1, ENC_BIG_ENDIAN);
 528   offset += 1;
 529
 530   proto_tree_add_item(tree, hf_pptp_error,           tvb, offset, 1, ENC_BIG_ENDIAN);
 531   offset += 1;
 532
 533   proto_tree_add_item(tree, hf_pptp_cause,           tvb, offset, 2, ENC_BIG_ENDIAN);
 534   offset += 2;
 535
 536   proto_tree_add_item(tree, hf_pptp_reserved,        tvb, offset, 2, ENC_NA);
 537   offset += 2;
 538
 539   proto_tree_add_item(tree, hf_pptp_call_statistics, tvb, offset, 64, ENC_ASCII|ENC_NA);
 540 }
 541
 542 static void
 543 dissect_error_notify(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree)
 544 {
 545   if (!tree)
 546     return;
 547
 548   proto_tree_add_item(tree, hf_pptp_peer_call_id,      tvb, offset, 2, ENC_BIG_ENDIAN);
 549   offset += 2;
 550
 551   proto_tree_add_item(tree, hf_pptp_reserved,          tvb, offset, 2, ENC_NA);
 552   offset += 2;
 553
 554   proto_tree_add_item(tree, hf_pptp_crc_errors,        tvb, offset, 4, ENC_BIG_ENDIAN);
 555   offset += 4;
 556
 557   proto_tree_add_item(tree, hf_pptp_framing_errors,    tvb, offset, 4, ENC_BIG_ENDIAN);
 558   offset += 4;
 559
 560   proto_tree_add_item(tree, hf_pptp_hardware_overruns, tvb, offset, 4, ENC_BIG_ENDIAN);
 561   offset += 4;
 562
 563   proto_tree_add_item(tree, hf_pptp_buffer_overruns,   tvb, offset, 4, ENC_BIG_ENDIAN);
 564   offset += 4;
 565
 566   proto_tree_add_item(tree, hf_pptp_timeout_errors,    tvb, offset, 4, ENC_BIG_ENDIAN);
 567   offset += 4;
 568
 569   proto_tree_add_item(tree, hf_pptp_alignment_errors,  tvb, offset, 4, ENC_BIG_ENDIAN);
 570 }
 571
 572 static void
 573 dissect_set_link(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree)
 574 {
 575   if (!tree)
 576       return;
 577
 578   proto_tree_add_item(tree, hf_pptp_peer_call_id, tvb, offset, 2, ENC_BIG_ENDIAN);
 579   offset += 2;
 580
 581   proto_tree_add_item(tree, hf_pptp_reserved,     tvb, offset, 2, ENC_NA);
 582   offset += 2;
 583
 584   proto_tree_add_item(tree, hf_pptp_send_accm,    tvb, offset, 4, ENC_BIG_ENDIAN);
 585   offset += 4;
 586
 587   proto_tree_add_item(tree, hf_pptp_receive_accm, tvb, offset, 4, ENC_BIG_ENDIAN);
 588 }
 589
 590 static void
 591 dissect_pptp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 592 {
 593   proto_tree *pptp_tree = NULL;
 594   proto_item *item      = NULL;
 595   int         offset    = 0;
 596   guint16     len;
 597   guint16     control_message_type;
 598
 599   col_set_str(pinfo->cinfo, COL_PROTOCOL, "PPTP");
 600   col_clear(pinfo->cinfo, COL_INFO);
 601
 602   len        = tvb_get_ntohs(tvb, offset);
 603   control_message_type = tvb_get_ntohs(tvb, offset + 8);
 604
 605   col_add_str(pinfo->cinfo, COL_INFO,
 606               val_to_str(control_message_type, control_message_type_vals,
 607                          "Unknown control type (%d)"));
 608
 609   if (tree) {
 610     proto_item *ti;
 611
 612     ti = proto_tree_add_item(tree, proto_pptp, tvb, offset, len, ENC_NA);
 613     pptp_tree = proto_item_add_subtree(ti, ett_pptp);
 614
 615     proto_tree_add_item(pptp_tree, hf_pptp_length, tvb, offset, 2, ENC_BIG_ENDIAN);
 616
 617     proto_tree_add_item(pptp_tree, hf_pptp_message_type, tvb, offset+2, 2, ENC_BIG_ENDIAN);
 618
 619     item = proto_tree_add_item(pptp_tree, hf_pptp_magic_cookie, tvb, offset+4, 4, ENC_BIG_ENDIAN);
 620   }
 621
 622   if (tvb_get_ntohl(tvb, offset+4) == MAGIC_COOKIE)
 623     proto_item_append_text(item," (correct)");
 624   else {
 625     proto_item_append_text(item," (incorrect)");
 626     expert_add_info(pinfo, item, &ei_pptp_incorrect_magic_cookie);
 627   }
 628
 629   if (tree) {
 630     proto_tree_add_item(pptp_tree, hf_pptp_control_message_type, tvb, offset+8, 2, ENC_BIG_ENDIAN);
 631
 632     proto_tree_add_item(pptp_tree, hf_pptp_reserved, tvb, offset+10, 2, ENC_NA);
 633   }
 634
 635   offset += offset + 12;
 636
 637   switch(control_message_type){
 638     case CNTRL_REQ: /* Start-Control-Connection-Request */
 639       dissect_cntrl_req(tvb, offset, pinfo, pptp_tree);
 640       break;
 641     case CNTRL_REPLY: /* Start-Control-Connection-Reply */
 642       dissect_cntrl_reply(tvb, offset, pinfo, pptp_tree);
 643       break;
 644     case STOP_REQ: /* Stop-Control-Connection-Request */
 645       dissect_stop_req(tvb, offset, pinfo, pptp_tree);
 646       break;
 647     case STOP_REPLY: /* Stop-Control-Connection-Reply */
 648       dissect_stop_reply(tvb, offset, pinfo, pptp_tree);
 649       break;
 650     case ECHO_REQ: /* Echo-Request */
 651       dissect_echo_req(tvb, offset, pinfo, pptp_tree);
 652       break;
 653     case ECHO_REPLY: /* Echo-Reply */
 654       dissect_echo_reply(tvb, offset, pinfo, pptp_tree);
 655       break;
 656     case OUT_REQ: /* Outgoing-Call-Request */
 657       dissect_out_req(tvb, offset, pinfo, pptp_tree);
 658       break;
 659     case OUT_REPLY: /* Outgoing-Call-Reply */
 660       dissect_out_reply(tvb, offset, pinfo, pptp_tree);
 661       break;
 662     case IN_REQ: /* Incoming-Call-Request */
 663       dissect_in_req(tvb, offset, pinfo, pptp_tree);
 664       break;
 665     case IN_REPLY: /* Incoming-Call-Reply */
 666       dissect_in_reply(tvb, offset, pinfo, pptp_tree);
 667       break;
 668     case IN_CONNECTED: /* Incoming-Call-Connected */
 669       dissect_in_connected(tvb, offset, pinfo, pptp_tree);
 670       break;
 671     case CLEAR_REQ: /* Call-Clear-Request */
 672       dissect_clear_req(tvb, offset, pinfo, pptp_tree);
 673       break;
 674     case DISC_NOTIFY: /* Call-Disconnect-Notify */
 675       dissect_disc_notify(tvb, offset, pinfo, pptp_tree);
 676       break;
 677     case ERROR_NOTIFY: /* WAN-Error-Notify */
 678       dissect_error_notify(tvb, offset, pinfo, pptp_tree);
 679       break;
 680     case SET_LINK: /* Set-Link-Info */
 681       dissect_set_link(tvb, offset, pinfo, pptp_tree);
 682       break;
 683     default: /* Unknown Type... */
 684       dissect_unknown(tvb, offset, pinfo, pptp_tree);
 685       break;
 686   }
 687 }
 688
 689 void
 690 proto_register_pptp(void)
 691 {
 692   static gint *ett[] = {
 693     &ett_pptp,
 694   };
 695
 696   static hf_register_info hf[] = {
 697     { &hf_pptp_length,
 698       { "Length", "pptp.length",
 699         FT_UINT16, BASE_DEC, NULL, 0x0,
 700         "Total length in octets of this PPTP message", HFILL }
 701     },
 702     { &hf_pptp_message_type,
 703       { "Message type", "pptp.type",
 704         FT_UINT16, BASE_DEC, VALS(msgtype_vals), 0x0,
 705         "PPTP message type", HFILL }
 706     },
 707     { &hf_pptp_magic_cookie,
 708       { "Magic Cookie", "pptp.magic_cookie",
 709         FT_UINT32, BASE_HEX, NULL, 0x0,
 710         "This constant value is used as a sanity check on received messages", HFILL }
 711     },
 712     { &hf_pptp_control_message_type,
 713       { "Control Message Type", "pptp.control_message_type",
 714         FT_UINT16, BASE_DEC, VALS(control_message_type_vals), 0x0,
 715         NULL, HFILL }
 716     },
 717     { &hf_pptp_reserved,
 718       { "Reserved", "pptp.reserved",
 719         FT_BYTES, BASE_NONE, NULL, 0x0,
 720         "This field MUST be 0", HFILL }
 721     },
 722     { &hf_pptp_protocol_version,
 723       { "Protocol version", "pptp.protocol_version",
 724         FT_UINT16, BASE_DEC, NULL, 0x0,
 725         "The version of the PPTP protocol", HFILL }
 726     },
 727     { &hf_pptp_framing_capabilities,
 728       { "Framing Capabilities", "pptp.framing_capabilities",
 729         FT_UINT32, BASE_DEC, VALS(frametype_vals), 0x0,
 730         "A set of bits indicating the type of framing", HFILL }
 731     },
 732     { &hf_pptp_bearer_capabilities,
 733       { "Bearer Capabilities", "pptp.bearer_capabilities",
 734         FT_UINT32, BASE_DEC, VALS(bearertype_vals), 0x0,
 735         "A set of bits indicating the type of bearer", HFILL }
 736     },
 737     { &hf_pptp_maximum_channels,
 738       { "Maximum Channels", "pptp.maximum_channels",
 739         FT_UINT16, BASE_DEC, NULL, 0x0,
 740         "The total number of individual PPP sessions this PAC can support", HFILL }
 741     },
 742     { &hf_pptp_firmware_revision,
 743       { "Firmware Revision", "pptp.firmware_revision",
 744         FT_UINT16, BASE_DEC, NULL, 0x0,
 745         "This field contains the firmware revision", HFILL }
 746     },
 747     { &hf_pptp_host_name,
 748       { "Host Name", "pptp.host_name",
 749         FT_STRING, BASE_NONE, NULL, 0x0,
 750         "A 64 octet field containing the DNS name", HFILL }
 751     },
 752     { &hf_pptp_vendor_name,
 753       { "Vendor Name", "pptp.vendor_name",
 754         FT_STRING, BASE_NONE, NULL, 0x0,
 755         "A 64 octet field containing a vendor", HFILL }
 756     },
 757     { &hf_pptp_control_result,
 758       { "Result Code", "pptp.control_result",
 759         FT_UINT8, BASE_DEC, VALS(control_resulttype_vals), 0x0,
 760         "Indicates the result of the command channel establishment attempt", HFILL }
 761     },
 762     { &hf_pptp_error,
 763       { "Error Code", "pptp.error",
 764         FT_UINT8, BASE_DEC, VALS(errortype_vals), 0x0,
 765         NULL, HFILL }
 766     },
 767     { &hf_pptp_reason,
 768       { "Reason", "pptp.reason",
 769         FT_UINT8, BASE_DEC, VALS(reasontype_vals), 0x0,
 770         "Indicates the reason for the control connection being close", HFILL }
 771     },
 772     { &hf_pptp_stop_result,
 773       { "Result Code", "pptp.stop_result",
 774         FT_UINT8, BASE_DEC, VALS(stop_resulttype_vals), 0x0,
 775         "Indicates the result of the attempt to close the control connection", HFILL }
 776     },
 777     { &hf_pptp_identifier,
 778       { "Identifier", "pptp.identifier",
 779         FT_UINT32, BASE_DEC, NULL, 0x0,
 780         NULL, HFILL }
 781     },
 782     { &hf_pptp_echo_result,
 783       { "Result Code", "pptp.echo_result",
 784         FT_UINT8, BASE_DEC, VALS(echo_resulttype_vals), 0x0,
 785         "Indicates the result of the receipt of the Echo-Request", HFILL }
 786     },
 787     { &hf_pptp_call_id,
 788       { "Call ID", "pptp.call_id",
 789         FT_UINT16, BASE_DEC, NULL, 0x0,
 790         "A unique identifier, unique to a particular PAC-PNS pair assigned by the PNS", HFILL }
 791     },
 792     { &hf_pptp_call_serial_number,
 793       { "Call Serial Number", "pptp.call_serial_number",
 794         FT_UINT16, BASE_DEC, NULL, 0x0,
 795         "An identifier assigned by the PNS to this session for the purpose of identifying this particular session in logged session information", HFILL }
 796     },
 797    { &hf_pptp_minimum_bps,
 798      { "Minimum BPS", "pptp.minimum_bps",
 799        FT_UINT32, BASE_DEC, NULL, 0x0,
 800        "The lowest acceptable line speed (in bits/second) for this session", HFILL }
 801    },
 802    { &hf_pptp_maximum_bps,
 803      { "Maximum BPS", "pptp.maximum_bps",
 804        FT_UINT32, BASE_DEC, NULL, 0x0,
 805        "The highest acceptable line speed (in bits/second) for this session", HFILL }
 806    },
 807     { &hf_pptp_framing_type,
 808       { "Framing Type", "pptp.framing_type",
 809         FT_UINT32, BASE_DEC, VALS(frametype_vals), 0x0,
 810         "A value indicating the type of PPP framing to be used for this outgoing call", HFILL }
 811     },
 812     { &hf_pptp_bearer_type,
 813       { "Bearer Type", "pptp.bearer_type",
 814         FT_UINT32, BASE_DEC, VALS(bearertype_vals), 0x0,
 815         "A value indicating the bearer capability required for this outgoing call", HFILL }
 816     },
 817     { &hf_pptp_packet_receive_window_size,
 818       { "Packet Receive Window Size", "pptp.packet_receive_window_size",
 819         FT_UINT16, BASE_DEC, NULL, 0x0,
 820         "A unique identifier, unique to a particular PAC-PNS pair assigned by the PNS", HFILL }
 821     },
 822     { &hf_pptp_packet_processing_delay,
 823       { "Packet Processing Delay", "pptp.packet_processing_delay",
 824         FT_UINT16, BASE_DEC, NULL, 0x0,
 825         "A measure of the packet processing delay that might be imposed on data sent to the PNS from the PAC", HFILL }
 826     },
 827     { &hf_pptp_phone_number_length,
 828       { "Phone Number Length", "pptp.phone_number_length",
 829         FT_UINT16, BASE_DEC, NULL, 0x0,
 830         "The actual number of valid digits in the Phone Number field", HFILL }
 831     },
 832     { &hf_pptp_phone_number,
 833       { "Phone Number", "pptp.phone_number",
 834         FT_STRING, BASE_NONE, NULL, 0x0,
 835         "The number to be dialed to establish the outgoing session", HFILL }
 836     },
 837     { &hf_pptp_subaddress,
 838       { "Subaddress", "pptp.subaddress",
 839         FT_STRING, BASE_NONE, NULL, 0x0,
 840         "A 64 octet field used to specify additional dialing information.", HFILL }
 841     },
 842     { &hf_pptp_peer_call_id,
 843       { "Peer Call ID", "pptp.peer_call_id",
 844         FT_UINT16, BASE_DEC, NULL, 0x0,
 845         "This field is set to the value received in the Call ID field of the corresponding Outgoing-Call-Request message", HFILL }
 846     },
 847     { &hf_pptp_out_result,
 848       { "Result Code", "pptp.out_result",
 849         FT_UINT8, BASE_DEC, VALS(out_resulttype_vals), 0x0,
 850         "Indicates the result of the receipt of the Outgoing-Call-Request attempt", HFILL }
 851     },
 852     { &hf_pptp_cause,
 853       { "Cause Code", "pptp.cause",
 854         FT_UINT16, BASE_DEC, NULL, 0x0,
 855         "This field gives additional information", HFILL }
 856     },
 857     { &hf_pptp_connect_speed,
 858       { "Connect Speed", "pptp.connect_speed",
 859         FT_UINT32, BASE_DEC, NULL, 0x0,
 860         "The actual connection speed used, in bits/second.", HFILL }
 861     },
 862     { &hf_pptp_physical_channel_id,
 863       { "Physical Channel ID", "pptp.physical_channel_id",
 864         FT_UINT32, BASE_DEC, NULL, 0x0,
 865         "This field is set by the PAC in a vendor-specific manner to the physical channel number used to place this call", HFILL }
 866     },
 867     { &hf_pptp_dialed_number_length,
 868       { "Dialed Number Length", "pptp.dialed_number_length",
 869         FT_UINT16, BASE_DEC, NULL, 0x0,
 870         "The actual number of valid digits in the Dialed Number field", HFILL }
 871     },
 872     { &hf_pptp_dialed_number,
 873       { "Dialed Number", "pptp.dialed_number",
 874         FT_STRING, BASE_NONE, NULL, 0x0,
 875         "The number that was dialed by the caller", HFILL }
 876     },
 877
 878     { &hf_pptp_dialing_number_length,
 879       { "Dialing Number Length", "pptp.dialing_number_length",
 880         FT_UINT16, BASE_DEC, NULL, 0x0,
 881         "The actual number of valid digits in the Dialing Number field", HFILL }
 882     },
 883     { &hf_pptp_dialing_number,
 884       { "Dialing Number", "pptp.dialing_number",
 885         FT_STRING, BASE_NONE, NULL, 0x0,
 886         "The number from which the call was placed", HFILL }
 887     },
 888     { &hf_pptp_in_result,
 889       { "Result Code", "pptp.in_result",
 890         FT_UINT8, BASE_DEC, VALS(in_resulttype_vals), 0x0,
 891         "This value indicates the result of the Incoming-Call-Request attempt", HFILL }
 892     },
 893     { &hf_pptp_disc_result,
 894       { "Result Code", "pptp.disc_result",
 895         FT_UINT8, BASE_DEC, VALS(disc_resulttype_vals), 0x0,
 896         "This value indicates the reason for the disconnect", HFILL }
 897     },
 898     { &hf_pptp_call_statistics,
 899       { "Call Statistics", "pptp.call_Statistics",
 900         FT_STRING, BASE_NONE, NULL, 0x0,
 901         "This field is an ASCII string containing vendor-specific call statistics that can be logged for diagnostic purpose", HFILL }
 902     },
 903     { &hf_pptp_crc_errors,
 904       { "CRC Errors", "pptp.crc_errors",
 905         FT_UINT32, BASE_DEC, NULL, 0x0,
 906         "Number of PPP frames received with CRC errors since session was established", HFILL }
 907     },
 908     { &hf_pptp_framing_errors,
 909       { "Framing Errors", "pptp.framing_errors",
 910         FT_UINT32, BASE_DEC, NULL, 0x0,
 911         "Number of improperly framed PPP packets received", HFILL }
 912     },
 913     { &hf_pptp_hardware_overruns,
 914       { "Hardware overruns", "pptp.hardware_overruns",
 915         FT_UINT32, BASE_DEC, NULL, 0x0,
 916         "Number of receive buffer over-runs since session was established", HFILL }
 917     },
 918     { &hf_pptp_buffer_overruns,
 919       { "Buffer overruns", "pptp.buffer_overruns",
 920         FT_UINT32, BASE_DEC, NULL, 0x0,
 921         "Number of buffer over-runs detected since session was established", HFILL }
 922     },
 923     { &hf_pptp_timeout_errors,
 924       { "Time-out Errors", "pptp.timeout_errors",
 925         FT_UINT32, BASE_DEC, NULL, 0x0,
 926         "Number of time-outs since call was established", HFILL }
 927     },
 928     { &hf_pptp_alignment_errors,
 929       { "Alignment Errors", "pptp.alignment_errors",
 930         FT_UINT32, BASE_DEC, NULL, 0x0,
 931         "Number of Alignment errors since call was established", HFILL }
 932     },
 933     { &hf_pptp_send_accm,
 934       { "Send ACCM", "pptp.send_accm",
 935         FT_UINT32, BASE_HEX, NULL, 0x0,
 936         "The send ACCM value the client should use to process outgoing PPP packets", HFILL }
 937     },
 938     { &hf_pptp_receive_accm,
 939       { "Receive ACCM", "pptp.receive_accm",
 940         FT_UINT32, BASE_HEX, NULL, 0x0,
 941         "The Receive ACCM value the client should use to process incoming PPP packets", HFILL }
 942     },
 943   };
 944
 945   static ei_register_info ei[] = {
 946      { &ei_pptp_incorrect_magic_cookie, { "pptp.magic_cookie.incorrect", PI_PROTOCOL, PI_WARN, "Incorrect Magic Cookie", EXPFILL }},
 947   };
 948
 949   expert_module_t* expert_pptp;
 950
 951   proto_pptp = proto_register_protocol("Point-to-Point Tunnelling Protocol",
 952                                        "PPTP", "pptp");
 953   proto_register_field_array(proto_pptp, hf, array_length(hf));
 954   proto_register_subtree_array(ett, array_length(ett));
 955   expert_pptp = expert_register_protocol(proto_pptp);
 956   expert_register_field_array(expert_pptp, ei, array_length(ei));
 957 }
 958
 959 void
 960 proto_reg_handoff_pptp(void)
 961 {
 962   dissector_handle_t pptp_handle;
 963
 964   pptp_handle = create_dissector_handle(dissect_pptp, proto_pptp);
 965   dissector_add_uint("tcp.port", TCP_PORT_PPTP, pptp_handle);
 966   data_handle = find_dissector("data");
 967 }