summaryrefslogtreecommitdiffstats
path: root/epan/dissectors/packet-osi-options.c
blob: c4adc7c6fa4ada38bb0350b0700a46e7470619dd (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
/* packet-osi-options.c
 * Routines for the decode of ISO/OSI option part
 * Covers:
 * ISO  8473 CLNP (ConnectionLess Mode Network Service Protocol)
 * ISO 10589 ISIS (Intradomain Routing Information Exchange Protocol)
 * ISO  9542 ESIS (End System To Intermediate System Routing Exchange Protocol)
 *
 * Ralf Schneider <Ralf.Schneider@t-online.de>
 *
 * Wireshark - Network traffic analyzer
 * By Gerald Combs <gerald@wireshark.org>
 * Copyright 1998 Gerald Combs
 *
 * SPDX-License-Identifier: GPL-2.0-or-later
 */

#include "config.h"

#include <epan/packet.h>
#include <epan/expert.h>
#include "packet-osi.h"
#include "packet-osi-options.h"


/* ATN traffic types (ICAO doc 9705 Edition3 SV5 5.6.2.2.6.7.3) */
#define ATN_TT_ATSC_NO_PREFERENCE       0x01
#define ATN_TT_ATSC_CLASS_A             0x10
#define ATN_TT_ATSC_CLASS_B             0x11
#define ATN_TT_ATSC_CLASS_C             0x12
#define ATN_TT_ATSC_CLASS_D             0x13
#define ATN_TT_ATSC_CLASS_E             0x14
#define ATN_TT_ATSC_CLASS_F             0x15
#define ATN_TT_ATSC_CLASS_G             0x16
#define ATN_TT_ATSC_CLASS_H             0x17
#define ATN_TT_AOC_NO_PREFERENCE        0x21
#define ATN_TT_AOC_G                    0x22
#define ATN_TT_AOC_V                    0x23
#define ATN_TT_AOC_S                    0x24
#define ATN_TT_AOC_H                    0x25
#define ATN_TT_AOC_M                    0x26
#define ATN_TT_AOC_G_V                  0x27
#define ATN_TT_AOC_G_V_S                0x28
#define ATN_TT_AOC_G_V_H_S              0x29
#define ATN_TT_ADM_NO_PREFERENCE        0x30
#define ATN_TT_SYS_MGMT_NO_PREFERENCE   0x60

/* ATN security classification (ICAO doc 9705 Edition3 SV5 5.6.2.2.6.8.3) */
#define ATN_SC_UNCLASSIFIED             0x01
#define ATN_SC_RESTRICTED               0x02
#define ATN_SC_CONFIDENTIAL             0x03
#define ATN_SC_SECRET                   0x04
#define ATN_SC_TOP_SECRET               0x05

/* ATN security label records */
#define OSI_OPT_SECURITY_ATN_SR         0xc0
#define OSI_OPT_SECURITY_ATN_TT         0x0f
#define OSI_OPT_SECURITY_ATN_SC         0x03
#define OSI_OPT_SECURITY_ATN_SR_LEN     6
#define OSI_OPT_SECURITY_ATN_TT_LEN     1
#define OSI_OPT_SECURITY_ATN_SC_LEN     1
#define OSI_OPT_SECURITY_ATN_SI_MAX_LEN 8


#define OSI_OPT_SECURITY                0xc5
#define OSI_OPT_QOS_MAINTANANCE         0xc3
#define OSI_OPT_PRIORITY                0xcd
#define OSI_OPT_ADDRESS_MASK            0xe1
#define OSI_OPT_SNPA_MASK               0xe2
#define OSI_OPT_ES_CONFIG_TIMER         0xc6

#define OSI_OPT_MAX_PRIORITY            0x0e

#define OSI_OPT_PADDING                 0xcc
#define OSI_OPT_SOURCE_ROUTING          0xc8
#define OSI_OPT_RECORD_OF_ROUTE         0xcb
#define OSI_OPT_REASON_OF_DISCARD       0xc1

#define OSI_OPT_SEC_MASK                0xc0
#define OSI_OPT_SEC_RESERVED            0x00
#define OSI_OPT_SEC_SRC_ADR_SPEC        0x01
#define OSI_OPT_SEC_DST_ADR_SPEC        0x02
#define OSI_OPT_SEC_GLOBAL_UNIQUE       0x03

#define OSI_OPT_QOS_MASK                0xc0
#define OSI_OPT_QOS_RESERVED            0x00
#define OSI_OPT_QOS_SRC_ADR_SPEC        0x01
#define OSI_OPT_QOS_DST_ADR_SPEC        0x02
#define OSI_OPT_QOS_GLOBAL_UNIQUE       0x03

#define OSI_OPT_QOS_SUB_MASK            0x3f
#define OSI_OPT_QOS_SUB_RSVD            0x20
#define OSI_OPT_QOS_SUB_SEQ_VS_TRS      0x10
#define OSI_OPT_QOS_SUB_CONG_EXPED      0x08
#define OSI_OPT_QOS_SUB_TSD_VS_COST     0x04
#define OSI_OPT_QOS_SUB_RESERR_TRS      0x02
#define OSI_OPT_QOS_SUB_RESERR_COST     0x01

#define OSI_OPT_RFD_GENERAL             0x00
#define OSI_OPT_RFD_ADDRESS             0x08
#define OSI_OPT_RFD_SOURCE_ROUTING      0x09
#define OSI_OPT_RFD_LIFETIME            0x0a
#define OSI_OPT_RFD_PDU_DISCARDED       0x0b
#define OSI_OPT_RFD_REASSEMBLY          0x0c

#define OSI_OPT_RFD_MASK                0xf0
#define OSI_OPT_RFD_SUB_MASK            0x0f

extern gboolean clnp_decode_atn_options; /* as defined in packet-clnp.c */
extern int hf_clnp_atntt; /* as defined in packet-clnp.c */
extern int hf_clnp_atnsc; /* as defined in packet-clnp.c */

/* Generated from convert_proto_tree_add_text.pl */
static int hf_osi_options_address_mask = -1;
static int hf_osi_options_transit_delay_vs_cost = -1;
static int hf_osi_options_rtd_general = -1;
static int hf_osi_options_residual_error_prob_vs_transit_delay = -1;
static int hf_osi_options_qos_sequencing_vs_transit_delay = -1;
static int hf_osi_options_rtd_address = -1;
static int hf_osi_options_congestion_experienced = -1;
static int hf_osi_options_esct = -1;
static int hf_osi_options_rtd_reassembly = -1;
static int hf_osi_options_qos_maintenance = -1;
static int hf_osi_options_security_type = -1;
static int hf_osi_options_route_recording = -1;
static int hf_osi_options_last_hop = -1;
static int hf_osi_options_route = -1;
static int hf_osi_options_rtd_lifetime = -1;
static int hf_osi_options_rtd_source_routing = -1;
static int hf_osi_options_padding = -1;
static int hf_osi_options_rfd_error_class = -1;
static int hf_osi_options_snpa_mask = -1;
static int hf_osi_options_source_routing = -1;
static int hf_osi_options_priority = -1;
static int hf_osi_options_qos_reserved = -1;
static int hf_osi_options_residual_error_prob_vs_cost = -1;
static int hf_osi_options_rtd_pdu_discarded = -1;
static int hf_osi_options_rfd_field = -1;

static gint ett_osi_options       = -1;
static gint ett_osi_qos           = -1;
static gint ett_osi_route         = -1;
static gint ett_osi_redirect      = -1;

static expert_field ei_osi_options_none = EI_INIT;
static expert_field ei_osi_options_rfd_error_class = EI_INIT;

static const guchar atn_security_registration_val[] = {
  0x06, 0x04, 0x2b, 0x1b, 0x00, 0x00
}; /* =iso(1).org(3).ICAO(27).ATN(0).TrafficType(0)*/

static const value_string osi_opt_sec_atn_sr_vals[] = {
  {OSI_OPT_SECURITY_ATN_SR, "ATN Security Label"},
  {0,                       NULL}
};

static const value_string osi_opt_sec_atn_si_vals[] = {
  {OSI_OPT_SECURITY_ATN_TT, "Traffic Type and Routing"},
  {OSI_OPT_SECURITY_ATN_SC, "Security classification"},
  {0,                       NULL}
};

static const value_string osi_opt_sec_atn_tt_vals[] = {
  {ATN_TT_ATSC_NO_PREFERENCE,     "ATSC No preference"},
  {ATN_TT_ATSC_CLASS_A,           "ATSC Class A"},
  {ATN_TT_ATSC_CLASS_B,           "ATSC Class B"},
  {ATN_TT_ATSC_CLASS_C,           "ATSC Class C"},
  {ATN_TT_ATSC_CLASS_D,           "ATSC Class D"},
  {ATN_TT_ATSC_CLASS_E,           "ATSC Class E"},
  {ATN_TT_ATSC_CLASS_F,           "ATSC Class F"},
  {ATN_TT_ATSC_CLASS_G,           "ATSC Class G"},
  {ATN_TT_ATSC_CLASS_H,           "ATSC Class H"},
  {ATN_TT_AOC_NO_PREFERENCE,      "AOC No preference"},
  {ATN_TT_AOC_G,                  "AOC Gatelink only"},
  {ATN_TT_AOC_V,                  "AOC VHF only"},
  {ATN_TT_AOC_S,                  "AOC Satellite only"},
  {ATN_TT_AOC_H,                  "AOC HF only"},
  {ATN_TT_AOC_M,                  "AOC Mode S only"},
  {ATN_TT_AOC_G_V,                "AOC Gatelink first, then VHF"},
  {ATN_TT_AOC_G_V_S,              "AOC Gatelink first, then VHF, then Satellite"},
  {ATN_TT_AOC_G_V_H_S,            "AOC Gatelink first, then VHF, then HF, then Satellite"},
  {ATN_TT_ADM_NO_PREFERENCE,      "ATN Administrative No preference"},
  {ATN_TT_SYS_MGMT_NO_PREFERENCE, "ATN Systems Management No preference"},
  {0,                             NULL}
};

static const value_string osi_opt_sec_atn_sc_vals[] = {
  {ATN_SC_UNCLASSIFIED, "unclassified"},
  {ATN_SC_RESTRICTED,   "restricted"},
  {ATN_SC_CONFIDENTIAL, "confidential"},
  {ATN_SC_SECRET,       "secret"},
  {ATN_SC_TOP_SECRET,   "top secret"},
  {0,                   NULL}
};

static const value_string osi_opt_sec_vals[] = {
  {OSI_OPT_SEC_RESERVED,      "Reserved"},
  {OSI_OPT_SEC_SRC_ADR_SPEC,  "Source Address Specific"},
  {OSI_OPT_SEC_DST_ADR_SPEC,  "Destination Address Specific"},
  {OSI_OPT_SEC_GLOBAL_UNIQUE, "Globally Unique"},
  {0,                         NULL}
};

static const value_string osi_opt_qos_vals[] = {
  {OSI_OPT_QOS_RESERVED,      "Reserved"},
  {OSI_OPT_QOS_SRC_ADR_SPEC,  "Source Address Specific"},
  {OSI_OPT_QOS_DST_ADR_SPEC,  "Destination Address Specific"},
  {OSI_OPT_QOS_GLOBAL_UNIQUE, "Globally Unique"},
  {0,                         NULL}
};

static const value_string osi_opt_rfd_error_class[] = {
  {OSI_OPT_RFD_GENERAL, "General"},
  {OSI_OPT_RFD_ADDRESS, "Address"},
  {OSI_OPT_RFD_SOURCE_ROUTING, "Source Routing"},
  {OSI_OPT_RFD_LIFETIME, "Lifetime"},
  {OSI_OPT_RFD_PDU_DISCARDED, "PDU discarded"},
  {OSI_OPT_RFD_REASSEMBLY, "Reassembly"},
  {0,    NULL}
};

static const value_string osi_opt_rfd_general[] = {
  {0x00, "Reason not specified"},
  {0x01, "Protocol procedure error"},
  {0x02, "Incorrect checksum"},
  {0x03, "PDU discarded due to congestion"},
  {0x04, "Header syntax error ( cannot be parsed )"},
  {0x05, "Segmentation needed but not permitted"},
  {0x06, "Incomplete PDU received"},
  {0x07, "Duplicate option"},
  {0,    NULL}
};

static const value_string osi_opt_rfd_address[] = {
  {0x00, "Destination Address unreachable"},
  {0x01, "Destination Address unknown"},
  {0,    NULL}
};

static const value_string osi_opt_rfd_src_route[] = {
  {0x00, "Unspecified source routing error"},
  {0x01, "Syntax error in source routing field"},
  {0x02, "Unknown address in source routing field"},
  {0x03, "Path not acceptable"},
  {0,    NULL}
};

static const value_string osi_opt_rfd_lifetime[] = {
  {0x00, "Lifetime expired while data unit in transit"},
  {0x01, "Lifetime expired during reassembly"},
  {0,    NULL}
};

static const value_string osi_opt_rfd_discarded[] = {
  {0x00, "Unsupported option not specified"},
  {0x01, "Unsupported protocol version"},
  {0x02, "Unsupported security option"},
  {0x03, "Unsupported source routing option"},
  {0x04, "Unsupported recording of route option"},
  {0,    NULL}
};

static const value_string osi_opt_rfd_reassembly[] = {
  {0x00, "Reassembly interference"},
  {0,    NULL} };


static void
dissect_option_qos(const guint8 qos, proto_tree *tree, tvbuff_t *tvb, int offset)
{
  proto_item *ti;
  proto_tree *osi_qos_tree;

  ti = proto_tree_add_item(tree, hf_osi_options_qos_maintenance, tvb, offset, 1, ENC_BIG_ENDIAN);
  osi_qos_tree = proto_item_add_subtree(ti, ett_osi_qos);

  if ( ((qos & OSI_OPT_QOS_MASK) >> 6) == OSI_OPT_QOS_GLOBAL_UNIQUE) { /* Analye BIT field to get all Values */
    proto_tree_add_item(osi_qos_tree, hf_osi_options_qos_reserved, tvb, offset, 1, ENC_NA);
    proto_tree_add_item(osi_qos_tree, hf_osi_options_qos_sequencing_vs_transit_delay, tvb, offset, 1, ENC_NA);
    proto_tree_add_item(osi_qos_tree, hf_osi_options_congestion_experienced, tvb, offset, 1, ENC_NA);
    proto_tree_add_item(osi_qos_tree, hf_osi_options_transit_delay_vs_cost, tvb, offset, 1, ENC_NA);
    proto_tree_add_item(osi_qos_tree, hf_osi_options_residual_error_prob_vs_transit_delay, tvb, offset, 1, ENC_NA);
    proto_tree_add_item(osi_qos_tree, hf_osi_options_residual_error_prob_vs_cost, tvb, offset, 1, ENC_NA);
  }
}

static void
dissect_option_route(guchar parm_type, int offset, guchar parm_len,
                     tvbuff_t *tvb, proto_tree *tree )
{
  guchar      next_hop = 0;
  guint16     this_hop = 0;
  guchar      netl     = 0;
  guchar      last_hop = 0;
  guchar      cnt_hops = 0;
  guchar      crr      = 0;
  gchar*      str;

  proto_tree *osi_route_tree = NULL;

  if ( parm_type == OSI_OPT_SOURCE_ROUTING ) {
    next_hop = tvb_get_guint8(tvb, offset + 1);
    netl     = tvb_get_guint8(tvb, next_hop + 2);
    this_hop = offset + 2;  /* points to first netl */

    proto_tree_add_uint_format_value(tree, hf_osi_options_source_routing, tvb, offset + next_hop, netl,
                        tvb_get_guint8(tvb, offset), "%s   ( Next Hop Highlighted In Data Buffer )",
                        (tvb_get_guint8(tvb, offset) == 0) ? "Partial Source Routing" :
                                                             "Complete Source Routing");
  }
  else if ( parm_type == OSI_OPT_RECORD_OF_ROUTE ) {
    crr = tvb_get_guint8(tvb, offset);
    last_hop = tvb_get_guint8(tvb, offset + 1);
    osi_route_tree = proto_tree_add_subtree(tree, tvb, offset, parm_len, ett_osi_route, NULL,
                             (crr == 0) ? "Partial Route Recording" : "Complete Route Recording");

    /* Complete Route Recording or Partial Route Recording */
    proto_tree_add_uint_format_value(tree, hf_osi_options_route_recording, tvb, offset, 1, crr, "%s ",
                             (crr == 0) ? "Partial Route Recording" :
                                          "Complete Route Recording");

    /* "last_hop" is either :
     *  0x03 : special value for no NET recorded yet.
     *  0xFF : special value telling there is no more place
               in the Route Recording Allocated Length and
               therefore next NETs won't be recorded.
    *  Other value : Total length of recorded NETs so far.
    */
    if ( last_hop == 0x03 )
      proto_tree_add_uint_format(osi_route_tree, hf_osi_options_last_hop, tvb, offset + 1, 1, last_hop,
                          "No Network Entity Titles Recorded Yet");
    if ( last_hop == 0xFF )
      proto_tree_add_uint_format(osi_route_tree, hf_osi_options_last_hop, tvb, offset + 1, 1, last_hop,
                          "Recording Terminated : No more space !");

    if ( last_hop == 255 || last_hop == 0x03 )
      this_hop = parm_len + 1;   /* recording terminated,
                                  * or not begun, nothing to show */
    else
      this_hop = offset + 2;         /* points to first netl */
  }

  while ( this_hop < offset + last_hop -2 ) { /* -2 for crr and last_hop */
    netl = tvb_get_guint8(tvb, this_hop);
    str = print_nsap_net(wmem_packet_scope(), tvb, this_hop + 1, netl);
    proto_tree_add_string_format(osi_route_tree, hf_osi_options_route, tvb, this_hop, netl + 1, str,
                        "Hop #%3u NETL: %2u, NET: %s", cnt_hops++, netl, str);
    this_hop += 1 + netl;
  }
}


static void
dissect_option_rfd(const guchar error, const guchar field, int offset,
                   guchar len _U_, tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo )
{
  proto_item *ti;

  ti = proto_tree_add_item(tree, hf_osi_options_rfd_error_class, tvb, offset, 1, ENC_BIG_ENDIAN);

  switch ((error & OSI_OPT_RFD_MASK) >> 4)
  {
  case OSI_OPT_RFD_GENERAL:
    proto_tree_add_item(tree, hf_osi_options_rtd_general, tvb, offset, 1, ENC_BIG_ENDIAN);
  break;
  case OSI_OPT_RFD_ADDRESS:
    proto_tree_add_item(tree, hf_osi_options_rtd_address, tvb, offset, 1, ENC_BIG_ENDIAN);
  break;
  case OSI_OPT_RFD_SOURCE_ROUTING:
    proto_tree_add_item(tree, hf_osi_options_rtd_source_routing, tvb, offset, 1, ENC_BIG_ENDIAN);
  break;
  case OSI_OPT_RFD_LIFETIME:
    proto_tree_add_item(tree, hf_osi_options_rtd_lifetime, tvb, offset, 1, ENC_BIG_ENDIAN);
  break;
  case OSI_OPT_RFD_PDU_DISCARDED:
    proto_tree_add_item(tree, hf_osi_options_rtd_pdu_discarded, tvb, offset, 1, ENC_BIG_ENDIAN);
  break;
  case OSI_OPT_RFD_REASSEMBLY:
    proto_tree_add_item(tree, hf_osi_options_rtd_reassembly, tvb, offset, 1, ENC_BIG_ENDIAN);
  break;
  default:
    expert_add_info(pinfo, ti, &ei_osi_options_rfd_error_class);
  }

  proto_tree_add_uint(tree, hf_osi_options_rfd_field, tvb, offset + field, 1, field);
}

/* dissect ATN security label used for policy based interdomain routing.*/
/* For details see ICAO doc 9705 Edition 3 SV5 5.6.2.2.2.2 */
static void
dissect_option_atn_security_label(const guchar sub_type, guchar length,
                                  tvbuff_t *tvb, guint offset,
                                  proto_tree *tree)
{
  proto_tree *atn_sl_tree;
  guchar len = 0;
  guint8 tag_name = 0;
  guint  security_info_end = 0;

  /* check for ATN security label */
  if ( OSI_OPT_SECURITY_ATN_SR != sub_type )
    return;

  /* check Security Registration Length */
  len =  tvb_get_guint8(tvb, ++offset);
  if ( OSI_OPT_SECURITY_ATN_SR_LEN != len )
    return;

  /* check Security Registration ID */
  if ( tvb_memeql(tvb, ++offset , atn_security_registration_val, OSI_OPT_SECURITY_ATN_SR_LEN) )
    return;

  atn_sl_tree = proto_tree_add_subtree(tree, tvb, offset, length, ett_osi_qos, NULL,
                           val_to_str(sub_type, osi_opt_sec_atn_sr_vals, "Unknown (0x%x)"));

  offset += OSI_OPT_SECURITY_ATN_SR_LEN;

  /* Security Information length */
  len = tvb_get_guint8(tvb, offset);

  if ( OSI_OPT_SECURITY_ATN_SI_MAX_LEN < len )
    return;

  offset++;

  security_info_end = offset + len;
  while ( offset < security_info_end ) {
    /* check tag name length*/
    len = tvb_get_guint8(tvb, offset); /* check tag name length*/
    if ( len != 1 )
      return;

    offset++;

    tag_name = tvb_get_guint8(tvb, offset);
    offset++;

    switch(tag_name) {
      case OSI_OPT_SECURITY_ATN_TT:
        /* check tag set length*/
        len = tvb_get_guint8(tvb, offset);
        if ( len != OSI_OPT_SECURITY_ATN_TT_LEN )
          return;

        offset++;
        proto_tree_add_uint_format(atn_sl_tree, hf_clnp_atntt, tvb, offset, 1,
                                   tvb_get_guint8(tvb, offset), "%s: %s",
                                   val_to_str(OSI_OPT_SECURITY_ATN_TT, osi_opt_sec_atn_si_vals, "Unknown (0x%x)"),
                                   val_to_str(tvb_get_guint8(tvb, offset ), osi_opt_sec_atn_tt_vals, "Unknown (0x%x)"));
        offset += len;
        break;

      case OSI_OPT_SECURITY_ATN_SC:
        /* check tag set length*/
        len = tvb_get_guint8(tvb, offset);
        if ( len != OSI_OPT_SECURITY_ATN_SC_LEN )
          return;

        offset++;
        proto_tree_add_uint_format(atn_sl_tree, hf_clnp_atnsc, tvb, offset, 1,
                                   tvb_get_guint8(tvb, offset), "%s: %s",
                                   val_to_str(OSI_OPT_SECURITY_ATN_SC, osi_opt_sec_atn_si_vals, "Unknown (0x%x)"),
                                   val_to_str(tvb_get_guint8(tvb, offset ), osi_opt_sec_atn_sc_vals, "Unknown (0x%x)"));
        offset += len;
        break;

      default:
        return;
    }
  }
}

/* ############################## Dissection Functions ###################### */

/*
 * Name: dissect_osi_options()
 *
 * Description:
 *   Main entry area for esis de-mangling.  This will build the
 *   main esis tree data and call the sub-protocols as needed.
 *
 * Input:
 *   guchar       : length of option section
 *   tvbuff_t *   : tvbuff containing packet data
 *   int          : offset into packet where we are (packet_data[offset]== start
 *                  of what we care about)
 *   proto_tree * : tree of display data.  May be NULL.
 *
 * Output:
 *   void, but we will add to the proto_tree if it is not NULL.
 */
void
dissect_osi_options(guchar opt_len, tvbuff_t *tvb, int offset, proto_tree *tree, packet_info *pinfo)
{
  proto_item *ti;
  proto_tree *osi_option_tree = NULL;
  guchar      parm_len        = 0;
  guchar      parm_type       = 0;
  guint8      octet;

    osi_option_tree = proto_tree_add_subtree(tree, tvb, offset, opt_len,
                             ett_osi_options, &ti, "### Option Section ###");
    if ( 0 == opt_len ) {
       expert_add_info(pinfo, ti, &ei_osi_options_none);
       return;
    }

    while ( 0 < opt_len ) {
      parm_type = tvb_get_guint8(tvb, offset++);
      parm_len = tvb_get_guint8(tvb, offset++);

      switch ( parm_type ) {
        case OSI_OPT_QOS_MAINTANANCE:
          octet = tvb_get_guint8(tvb, offset);
          dissect_option_qos(octet, osi_option_tree, tvb, offset);
          break;

        case OSI_OPT_SECURITY:
          octet = tvb_get_guint8(tvb, offset);
          if ( clnp_decode_atn_options ) {
            dissect_option_atn_security_label(octet,parm_len,tvb, offset,
                                              osi_option_tree);
          } else {
            ti = proto_tree_add_item(osi_option_tree, hf_osi_options_security_type, tvb, offset, 1, ENC_BIG_ENDIAN);
            proto_item_set_len(ti, parm_len);
          }
          break;

        case OSI_OPT_PRIORITY:
          octet = tvb_get_guint8(tvb, offset);
          if ( OSI_OPT_MAX_PRIORITY >= octet ) {
            ti = proto_tree_add_item(osi_option_tree, hf_osi_options_priority, tvb, offset, 1, ENC_BIG_ENDIAN);
          } else {
            ti = proto_tree_add_uint_format_value(osi_option_tree, hf_osi_options_priority, tvb, offset, 1,
                                octet, "%u ( Invalid )", octet);
          }
          proto_item_set_len(ti, parm_len);
          break;

        case OSI_OPT_ADDRESS_MASK:
          proto_tree_add_bytes_format_value(osi_option_tree, hf_osi_options_address_mask, tvb, offset, parm_len,
                              NULL, "%s",
                              print_area(pinfo->pool, tvb, offset, parm_len));
          break;

        case OSI_OPT_SNPA_MASK:
          proto_tree_add_item(osi_option_tree, hf_osi_options_snpa_mask, tvb, offset, parm_len, ENC_NA);
          break;

        case OSI_OPT_ES_CONFIG_TIMER:
          ti = proto_tree_add_item(osi_option_tree, hf_osi_options_esct, tvb, offset, 2, ENC_BIG_ENDIAN);
          proto_item_set_len(ti, parm_len);          break;

        case OSI_OPT_PADDING:
          proto_tree_add_item(osi_option_tree, hf_osi_options_padding, tvb, offset, parm_len, ENC_NA);
          break;

        case OSI_OPT_SOURCE_ROUTING:
        case OSI_OPT_RECORD_OF_ROUTE:
          dissect_option_route(parm_type, offset, parm_len, tvb,
                               osi_option_tree);
          break;

        case OSI_OPT_REASON_OF_DISCARD:
          dissect_option_rfd(tvb_get_guint8(tvb, offset),
                             tvb_get_guint8(tvb, offset + 1), offset, parm_len,
                             tvb, osi_option_tree, pinfo);
          break;
      }
      opt_len -= parm_len + 2;
      offset  += parm_len;
    }
} /* dissect-osi-options */


/*
 * Name: proto_register_osi_options()
 *
 * Description:
 *      main register for esis protocol set.  We register some display
 *      formats and the protocol module variables.
 *
 *      NOTE: this procedure to autolinked by the makefile process that
 *      builds register.c
 *
 * Input:
 *      void
 *
 * Output:
 *      void
 */

void
proto_register_osi_options(void) {

  static hf_register_info hf[] =
  {
      /* Generated from convert_proto_tree_add_text.pl */
      { &hf_osi_options_qos_maintenance, { "Quality of service maintenance", "osi.options.qos.maintenance", FT_UINT8, BASE_DEC, VALS(osi_opt_qos_vals), OSI_OPT_QOS_MASK, NULL, HFILL }},
      { &hf_osi_options_qos_reserved, { "Reserved", "osi.options.qos.reserved", FT_BOOLEAN, 8, NULL, OSI_OPT_QOS_SUB_RSVD, NULL, HFILL }},
      { &hf_osi_options_qos_sequencing_vs_transit_delay, { "Sequencing versus transit delay", "osi.options.qos.seq_vs_trs", FT_BOOLEAN, 8, NULL, OSI_OPT_QOS_SUB_SEQ_VS_TRS, NULL, HFILL }},
      { &hf_osi_options_congestion_experienced, { "Congestion experienced", "osi.options.qos.cong_exped", FT_BOOLEAN, 8, NULL, OSI_OPT_QOS_SUB_CONG_EXPED, NULL, HFILL }},
      { &hf_osi_options_transit_delay_vs_cost, { "Transit delay versus cost", "osi.options.qos.tsd_vs_cost", FT_BOOLEAN, 8, NULL, OSI_OPT_QOS_SUB_TSD_VS_COST, NULL, HFILL }},
      { &hf_osi_options_residual_error_prob_vs_transit_delay, { "Residual error probability versus transit delay", "osi.options.qos.reserror_trs", FT_BOOLEAN, 8, NULL, OSI_OPT_QOS_SUB_RESERR_TRS, NULL, HFILL }},
      { &hf_osi_options_residual_error_prob_vs_cost, { "Residual error probability versus cost", "osi.options.qos.reserror_cost", FT_BOOLEAN, 8, NULL, OSI_OPT_QOS_SUB_RESERR_COST, NULL, HFILL }},
      { &hf_osi_options_source_routing, { "Source Routing", "osi.options.source_routing", FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL }},
      { &hf_osi_options_route_recording, { "Route Recording", "osi.options.route_recording", FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL }},
      { &hf_osi_options_last_hop, { "Last Hop", "osi.options.last_hop", FT_UINT8, BASE_HEX, NULL, 0x0, NULL, HFILL }},
      { &hf_osi_options_route, { "Route", "osi.options.route", FT_STRING, BASE_NONE, NULL, 0x0, NULL, HFILL }},
      { &hf_osi_options_rfd_error_class, { "Error Class", "osi.options.rfd.error_class", FT_UINT8, BASE_DEC, VALS(osi_opt_rfd_error_class), OSI_OPT_RFD_MASK, NULL, HFILL }},
      { &hf_osi_options_rtd_general, { "Reason for discard {General}", "osi.options.rtd_general", FT_UINT8, BASE_DEC, VALS(osi_opt_rfd_general), OSI_OPT_RFD_SUB_MASK, NULL, HFILL }},
      { &hf_osi_options_rtd_address, { "Reason for discard {Address}", "osi.options.rtd_address", FT_UINT8, BASE_DEC, VALS(osi_opt_rfd_address), OSI_OPT_RFD_SUB_MASK, NULL, HFILL }},
      { &hf_osi_options_rtd_source_routing, { "Reason for discard {Source Routing}", "osi.options.rtd_source_routing", FT_UINT8, BASE_DEC, VALS(osi_opt_rfd_src_route), OSI_OPT_RFD_SUB_MASK, NULL, HFILL }},
      { &hf_osi_options_rtd_lifetime, { "Reason for discard {Lifetime}", "osi.options.rtd_lifetime", FT_UINT8, BASE_DEC, VALS(osi_opt_rfd_lifetime), OSI_OPT_RFD_SUB_MASK, NULL, HFILL }},
      { &hf_osi_options_rtd_pdu_discarded, { "Reason for discard {PDU discarded}", "osi.options.rtd_pdu_discarded", FT_UINT8, BASE_DEC, VALS(osi_opt_rfd_discarded), OSI_OPT_RFD_SUB_MASK, NULL, HFILL }},
      { &hf_osi_options_rtd_reassembly, { "Reason for discard {Reassembly}", "osi.options.rtd_reassembly", FT_UINT8, BASE_DEC, VALS(osi_opt_rfd_reassembly), OSI_OPT_RFD_SUB_MASK, NULL, HFILL }},
      { &hf_osi_options_rfd_field, { "Field", "osi.options.rfd.field", FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL }},
      { &hf_osi_options_security_type, { "Security type", "osi.options.security_type", FT_UINT8, BASE_DEC, VALS(osi_opt_sec_vals), OSI_OPT_SEC_MASK, NULL, HFILL }},
      { &hf_osi_options_priority, { "Priority", "osi.options.priority", FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL }},
      { &hf_osi_options_address_mask, { "Address Mask", "osi.options.address_mask", FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL }},
      { &hf_osi_options_snpa_mask, { "SNPA Mask", "osi.options.snpa_mask", FT_SYSTEM_ID, BASE_NONE, NULL, 0x0, NULL, HFILL }},
      { &hf_osi_options_esct, { "ESCT (seconds)", "osi.options.esct", FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL }},
      { &hf_osi_options_padding, { "Padding", "osi.options.padding", FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL }},
  };

  static gint *ett[] = {
    &ett_osi_options,
    &ett_osi_qos,
    &ett_osi_route,
    &ett_osi_redirect
  };

  static ei_register_info ei[] = {
      { &ei_osi_options_none, { "osi.options.none", PI_PROTOCOL, PI_NOTE, "No Options for this PDU", EXPFILL }},
      { &ei_osi_options_rfd_error_class, { "osi.options.rfd.error_class.unknown", PI_PROTOCOL, PI_WARN, "UNKNOWN Error Class", EXPFILL }},
  };

  expert_module_t *expert_osi_options;

  proto_register_field_array(proto_osi, hf, array_length(hf));
  proto_register_subtree_array(ett, array_length(ett));
  expert_osi_options = expert_register_protocol(proto_osi);
  expert_register_field_array(expert_osi_options, ei, array_length(ei));
}

/*
 * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
 *
 * Local variables:
 * c-basic-offset: 2
 * tab-width: 8
 * indent-tabs-mode: nil
 * End:
 *
 * vi: set shiftwidth=2 tabstop=8 expandtab:
 * :indentSize=2:tabSize=8:noTabs=true:
 */