aboutsummaryrefslogtreecommitdiffstats
path: root/packet-llc.c
blob: 3bd505e93d2e5d27e2cf7a4f430e347f08859c5c (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
658
659
660
661
662
663
/* packet-llc.c
 * Routines for IEEE 802.2 LLC layer
 * Gilbert Ramirez <gram@alumni.rice.edu>
 *
 * $Id: packet-llc.c,v 1.116 2003/10/01 07:11:44 guy Exp $
 *
 * Ethereal - Network traffic analyzer
 * By Gerald Combs <gerald@ethereal.com>
 * Copyright 1998 Gerald Combs
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */

#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

#include <glib.h>
#include <epan/packet.h>
#include "oui.h"
#include "xdlc.h"
#include "etypes.h"
#include "llcsaps.h"
#include "bridged_pids.h"
#include "ppptypes.h"
#include "arcnet_pids.h"
#include "packet-fc.h"
#include "packet-ip.h"
#include "packet-ipx.h"
#include "packet-netbios.h"
#include "packet-vines.h"
#include <epan/sna-utils.h>

#include "packet-llc.h"

#define UDP_PORT_LLC1   12000
#define UDP_PORT_LLC2   12001
#define UDP_PORT_LLC3   12002
#define UDP_PORT_LLC4   12003
#define UDP_PORT_LLC5   12004

static int proto_llc = -1;
static int hf_llc_dsap = -1;
static int hf_llc_ssap = -1;
static int hf_llc_dsap_ig = -1;
static int hf_llc_ssap_cr = -1;
static int hf_llc_ctrl = -1;
static int hf_llc_type = -1;
static int hf_llc_oui = -1;
static int hf_llc_pid = -1;

static gint ett_llc = -1;
static gint ett_llc_ctrl = -1;

static dissector_table_t subdissector_table;
static dissector_table_t xid_subdissector_table;

static dissector_handle_t bpdu_handle;
static dissector_handle_t eth_handle;
static dissector_handle_t fddi_handle;
static dissector_handle_t tr_handle;
static dissector_handle_t data_handle;

/*
 * Group/Individual bit, in the DSAP.
 */
#define	DSAP_GI_BIT	0x01

/*
 * Command/Response bit, in the SSAP.
 *
 * The low-order bit of the SSAP apparently determines whether this
 * is a request or a response.  (RFC 1390, "Transmission of IP and
 * ARP over FDDI Networks", says
 *
 *	Command frames are identified by having the low order
 *	bit of the SSAP address reset to zero.  Response frames
 *	have the low order bit of the SSAP address set to one.
 *
 * and a page I've seen seems to imply that's part of 802.2.)
 */
#define	SSAP_CR_BIT	0x01

/*
 * Mask to extrace the SAP number from the DSAP or the SSAP.
 */
#define	SAP_MASK	0xFE

/*
 * These are for SSAP and DSAP, wth last bit always zero.
 * XXX - some DSAPs come in separate "individual" and "group" versions,
 * with the last bit 0 and 1, respectively (e.g., LLC Sub-layer Management,
 * IBM SNA Path Control, IBM Net Management), but, whilst 0xFE is
 * the ISO Network Layer Protocol, 0xFF is the Global LSAP.
 */
const value_string sap_vals[] = {
	{ SAP_NULL,           "NULL LSAP" },
	{ SAP_LLC_SLMGMT,     "LLC Sub-Layer Management" },
	{ SAP_SNA_PATHCTRL,   "SNA Path Control" },
	{ SAP_IP,             "TCP/IP" },
	{ SAP_SNA1,           "SNA" },
	{ SAP_SNA2,           "SNA" },
	{ SAP_PROWAY_NM_INIT, "PROWAY (IEC955) Network Management and Initialization" },
	{ SAP_NETWARE1,       "NetWare (unofficial?)" },
	{ SAP_OSINL1,         "ISO Network Layer (OSLAN 1)" },
	{ SAP_TI,             "Texas Instruments" },
	{ SAP_OSINL2,         "ISO Network Layer (unofficial?)" },
	{ SAP_OSINL3,         "ISO Network Layer (unofficial?)" },
	{ SAP_BPDU,           "Spanning Tree BPDU" },
	{ SAP_RS511,          "EIA RS-511 Manufacturing Message Service" },
	{ SAP_OSINL4,         "ISO Network Layer (OSLAN 2)" },
	{ SAP_X25,            "ISO 8208 (X.25 over 802.2)" },
	/*
	 * XXX - setting the group bit of SAP_X25 make 0x7F; is this just
	 * a group version of that?
	 */
	{ 0x7F,               "ISO 802.2" },
	{ SAP_XNS,            "XNS" },
	{ SAP_BACNET,         "BACnet" },
	{ SAP_NESTAR,         "Nestar" },
	{ SAP_PROWAY_ASLM,    "PROWAY (IEC955) Active Station List Maintenance" },
	{ SAP_ARP,            "ARP" },	/* XXX - hand to "dissect_arp()"? */
	{ SAP_SNAP,           "SNAP" },
	{ SAP_VINES1,         "Banyan Vines" },
	{ SAP_VINES2,         "Banyan Vines" },
	{ SAP_NETWARE2,       "NetWare" },
	{ SAP_NETBIOS,        "NetBIOS" },
	{ SAP_IBMNM,          "IBM Net Management" },
	{ SAP_HPEXT,          "HP Extended LLC" },
	{ SAP_UB,             "Ungermann-Bass" },
	{ SAP_RPL,            "Remote Program Load" },
	{ SAP_OSINL5,         "ISO Network Layer" },
	{ SAP_GLOBAL,         "Global LSAP" },
	{ 0x00,               NULL }
};

/*
 * See
 *
 * http://www.cisco.com/univercd/cc/td/doc/product/lan/trsrb/vlan.htm
 *
 * for the PIDs for VTP and DRiP that go with an OUI of OUI_CISCO.
 */
const value_string oui_vals[] = {
	{ OUI_ENCAP_ETHER, "Encapsulated Ethernet" },
/*
http://www.cisco.com/univercd/cc/td/doc/product/software/ios113ed/113ed_cr/ibm_r/brprt1/brsrb.htm
*/
	{ OUI_CISCO,       "Cisco" },
	{ OUI_CISCO_90,    "Cisco IOS 9.0 Compatible" },
	{ OUI_BRIDGED,     "Frame Relay or ATM bridged frames" },
				/* RFC 2427, RFC 2684 */
	{ OUI_ATM_FORUM,   "ATM Forum" },
	{ OUI_CABLE_BPDU,  "DOCSIS Spanning Tree" }, /* DOCSIS spanning tree BPDU */
	{ OUI_APPLE_ATALK, "Apple (AppleTalk)" },
	{ OUI_NORTEL,      "Nortel Networks SONMP" },
	{ 0,               NULL }
};

/*
 * Hash table for translating OUIs to a dissector table/field info pair;
 * the dissector table maps PID values to dissectors, and the field
 * corresponds to the PID for that OUI.
 */
typedef struct {
	dissector_table_t table;
	hf_register_info *field_info;
} oui_info_t;

static GHashTable *oui_info_table = NULL;

/*
 * Add an entry for a new OUI.
 */
void
llc_add_oui(guint32 oui, const char *table_name, char *table_ui_name,
    hf_register_info *hf_item)
{
	oui_info_t *new_info;

	new_info = g_malloc(sizeof (oui_info_t));
	new_info->table = register_dissector_table(table_name,
	    table_ui_name, FT_UINT16, BASE_HEX);
	new_info->field_info = hf_item;

	/*
	 * Create the hash table for OUI information, if it doesn't
	 * already exist.
	 */
	if (oui_info_table == NULL) {
		oui_info_table = g_hash_table_new(g_direct_hash,
		    g_direct_equal);
	}
	g_hash_table_insert(oui_info_table, (gpointer)oui, new_info);
}

void
capture_llc(const guchar *pd, int offset, int len, packet_counts *ld) {

	int		is_snap;
	guint16		control;
	int		llc_header_len;
	guint32		oui;
	guint16		etype;

	if (!BYTES_ARE_IN_FRAME(offset, len, 2)) {
		ld->other++;
		return;
	}
	is_snap = (pd[offset] == SAP_SNAP) && (pd[offset+1] == SAP_SNAP);
	llc_header_len = 2;	/* DSAP + SSAP */

	/*
	 * XXX - the page referred to in the comment above about the
	 * Command/Response bit also implies that LLC Type 2 always
	 * uses extended operation, so we don't need to determine
	 * whether it's basic or extended operation; is that the case?
	 */
	control = get_xdlc_control(pd, offset+2, pd[offset+1] & SSAP_CR_BIT);
	llc_header_len += XDLC_CONTROL_LEN(control, TRUE);
	if (is_snap)
		llc_header_len += 5;	/* 3 bytes of OUI, 2 bytes of protocol ID */
	if (!BYTES_ARE_IN_FRAME(offset, len, llc_header_len)) {
		ld->other++;
		return;
	}

	if (is_snap) {
		oui = pd[offset+3] << 16 | pd[offset+4] << 8 | pd[offset+5];
		if (XDLC_IS_INFORMATION(control)) {
			etype = pntohs(&pd[offset+6]);
			switch (oui) {

			case OUI_ENCAP_ETHER:
			case OUI_CISCO_90:
			case OUI_APPLE_ATALK:
				/* No, I have no idea why Apple used
				   one of their own OUIs, rather than
				   OUI_ENCAP_ETHER, and an Ethernet
				   packet type as protocol ID, for
				   AppleTalk data packets - but used
				   OUI_ENCAP_ETHER and an Ethernet
				   packet type for AARP packets. */
				capture_ethertype(etype, pd, offset+8, len,
				    ld);
				break;
			case OUI_CISCO:
				capture_ethertype(etype, pd, offset + 8, len,
				    ld);
				break;
			default:
				ld->other++;
				break;
			}
		}
	}
	else {
		/* non-SNAP */
		if (XDLC_IS_INFORMATION(control)) {
			switch (pd[offset]) {

			case SAP_IP:
				capture_ip(pd, offset + llc_header_len, len,
				    ld);
				break;

			case SAP_NETWARE1:
			case SAP_NETWARE2:
				capture_ipx(ld);
				break;

			case SAP_NETBIOS:
				capture_netbios(ld);
				break;

			case SAP_VINES1:
			case SAP_VINES2:
				capture_vines(ld);
				break;

			default:
				ld->other++;
				break;
			}
		}
	}
}

static void
dissect_llc(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
	proto_tree	*llc_tree = NULL;
	proto_item	*ti = NULL;
	int		is_snap;
	guint16		control;
	int		llc_header_len;
	guint8		dsap, ssap;
	tvbuff_t	*next_tvb;

	if (check_col(pinfo->cinfo, COL_PROTOCOL)) {
		col_set_str(pinfo->cinfo, COL_PROTOCOL, "LLC");
	}
	if (check_col(pinfo->cinfo, COL_INFO)) {
		col_clear(pinfo->cinfo, COL_INFO);
	}

	dsap = tvb_get_guint8(tvb, 0);
	if (tree) {
		ti = proto_tree_add_item(tree, proto_llc, tvb, 0, -1, FALSE);
		llc_tree = proto_item_add_subtree(ti, ett_llc);
		proto_tree_add_uint(llc_tree, hf_llc_dsap, tvb, 0,
			1, dsap & SAP_MASK);
		proto_tree_add_boolean(llc_tree, hf_llc_dsap_ig, tvb, 0,
			1, dsap & DSAP_GI_BIT);
	} else
		llc_tree = NULL;

	ssap = tvb_get_guint8(tvb, 1);
	if (tree) {
		proto_tree_add_uint(llc_tree, hf_llc_ssap, tvb, 1,
			1, ssap & SAP_MASK);
		proto_tree_add_boolean(llc_tree, hf_llc_ssap_cr, tvb, 1,
			1, ssap & SSAP_CR_BIT);
	} else
		llc_tree = NULL;

	is_snap = (dsap == SAP_SNAP) && (ssap == SAP_SNAP);
	llc_header_len = 2;	/* DSAP + SSAP */

	/*
	 * XXX - the page referred to in the comment above about the
	 * Command/Response bit also implies that LLC Type 2 always
	 * uses extended operation, so we don't need to determine
	 * whether it's basic or extended operation; is that the case?
	 */
	control = dissect_xdlc_control(tvb, 2, pinfo, llc_tree,
				hf_llc_ctrl, ett_llc_ctrl,
				ssap & SSAP_CR_BIT, TRUE, FALSE);
	llc_header_len += XDLC_CONTROL_LEN(control, TRUE);
	if (is_snap)
		llc_header_len += 5;	/* 3 bytes of OUI, 2 bytes of protocol ID */

	if (tree)
		proto_item_set_len(ti, llc_header_len);

	if (is_snap) {
		dissect_snap(tvb, 3, pinfo, tree, llc_tree, control,
		    hf_llc_oui, hf_llc_type, hf_llc_pid, 2);
	}
	else {
		if (check_col(pinfo->cinfo, COL_INFO)) {
			col_append_fstr(pinfo->cinfo, COL_INFO,
			    "; DSAP %s %s, SSAP %s %s",
			    val_to_str(dsap & SAP_MASK, sap_vals, "%02x"),
			    dsap & DSAP_GI_BIT ?
			      "Group" : "Individual",
			    val_to_str(ssap & SAP_MASK, sap_vals, "%02x"),
			    ssap & SSAP_CR_BIT ?
			      "Response" : "Command"
			);
		}

		if (tvb_length_remaining(tvb, llc_header_len) > 0) {
			next_tvb = tvb_new_subset(tvb, llc_header_len, -1, -1);
			if (XDLC_IS_INFORMATION(control)) {
				/*
				 * Non-SNAP I or UI frame.
				 * Try the regular LLC subdissector table
				 * with the DSAP.
				 */
				if (!dissector_try_port(subdissector_table,
				    dsap, next_tvb, pinfo, tree)) {
					call_dissector(data_handle, next_tvb,
					    pinfo, tree);
				}
			} else if ((control & (XDLC_U_MODIFIER_MASK|XDLC_U))
			    == (XDLC_XID|XDLC_U)) {
				/*
				 * Non-SNAP XID frame.
				 * Try the XID LLC subdissector table
				 * with the DSAP.
				 */
				if (!dissector_try_port(xid_subdissector_table,
				    dsap, next_tvb, pinfo, tree)) {
					call_dissector(data_handle, next_tvb,
					    pinfo, tree);
				}
			} else {
				call_dissector(data_handle, next_tvb, pinfo,
				    tree);
			}
		}
	}
}

/*
 * Dissect SNAP header; used elsewhere, e.g. in the Frame Relay dissector.
 */
void
dissect_snap(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree,
    proto_tree *snap_tree, int control, int hf_oui, int hf_type, int hf_pid,
    int bridge_pad)
{
	guint32		oui;
	guint16		etype;
	tvbuff_t	*next_tvb;
	oui_info_t	*oui_info;
	dissector_table_t subdissector_table;
	int		hf;

	oui =	tvb_get_ntoh24(tvb, offset);
	etype = tvb_get_ntohs(tvb, offset+3);

	if (check_col(pinfo->cinfo, COL_INFO)) {
		col_append_fstr(pinfo->cinfo, COL_INFO,
		    "; SNAP, OUI 0x%06X (%s), PID 0x%04X",
		    oui, val_to_str(oui, oui_vals, "Unknown"), etype);
	}
	if (tree) {
		proto_tree_add_uint(snap_tree, hf_oui, tvb, offset, 3, oui);
	}

	switch (oui) {

	case OUI_ENCAP_ETHER:
	case OUI_CISCO_90:
	case OUI_APPLE_ATALK:
		/* No, I have no idea why Apple used
		   one of their own OUIs, rather than
		   OUI_ENCAP_ETHER, and an Ethernet
		   packet type as protocol ID, for
		   AppleTalk data packets - but used
		   OUI_ENCAP_ETHER and an Ethernet
		   packet type for AARP packets. */
		if (XDLC_IS_INFORMATION(control)) {
			ethertype(etype, tvb, offset+5,
			    pinfo, tree, snap_tree, hf_type, -1, 0);
		} else {
			next_tvb = tvb_new_subset(tvb, offset+5, -1, -1);
			call_dissector(data_handle,next_tvb, pinfo, tree);
		}
		break;

	case OUI_BRIDGED:
		/*
		 * MAC frames bridged over ATM (RFC 2684) or Frame Relay
		 * (RFC 2427).
		 *
		 * We have to figure out how much padding to put
		 * into the frame.  We were handed a "bridge_pad"
		 * argument which should be 0 for Frame Relay and
		 * 2 for ATM; we add to that the amount of padding
		 * common to both bridging types.
		 */
		if (tree) {
			proto_tree_add_uint(snap_tree, hf_pid, tvb, offset+3, 2,
			    etype);
		}

		switch (etype) {

		case BPID_ETH_WITH_FCS:
		case BPID_ETH_WITHOUT_FCS:
			next_tvb = tvb_new_subset(tvb, offset+5+bridge_pad,
			    -1, -1);
			call_dissector(eth_handle, next_tvb, pinfo, tree);
			break;

		case BPID_802_5_WITH_FCS:
		case BPID_802_5_WITHOUT_FCS:
			/*
			 * We treat the last padding byte as the Access
			 * Control byte, as that's what the Token
			 * Ring dissector expects the first byte to
			 * be.
			 */
			next_tvb = tvb_new_subset(tvb, offset+5+bridge_pad,
			    -1, -1);
			call_dissector(tr_handle, next_tvb, pinfo, tree);
			break;

		case BPID_FDDI_WITH_FCS:
		case BPID_FDDI_WITHOUT_FCS:
			next_tvb = tvb_new_subset(tvb, offset+5+1+bridge_pad,
			    -1, -1);
			call_dissector(fddi_handle, next_tvb, pinfo, tree);
			break;

		case BPID_BPDU:
			next_tvb = tvb_new_subset(tvb, offset+5, -1, -1);
			call_dissector(bpdu_handle, next_tvb, pinfo, tree);
			break;

		default:
			next_tvb = tvb_new_subset(tvb, offset+5, -1, -1);
			call_dissector(data_handle,next_tvb, pinfo, tree);
			break;
		}
		break;

	case OUI_CABLE_BPDU:    /* DOCSIS cable modem spanning tree BPDU */
		if (tree) {
			proto_tree_add_uint(snap_tree, hf_pid, tvb, offset+3, 2,
			    etype);
		}
		next_tvb = tvb_new_subset(tvb, offset+5, -1, -1);
		call_dissector(bpdu_handle, next_tvb, pinfo, tree);
		break;

	default:
		/*
		 * Do we have information for this OUI?
		 */
		oui_info = g_hash_table_lookup(oui_info_table, (gpointer)oui);
		if (oui_info != NULL) {
			/*
			 * Yes - use it.
			 */
			hf = *oui_info->field_info->p_id;
			subdissector_table = oui_info->table;
		} else {
			/*
			 * No, use hf_pid for the PID and just dissect
			 * the payload as data.
			 */
			hf = hf_pid;
			subdissector_table = NULL;
		}
		if (tree) {
			proto_tree_add_uint(snap_tree, hf, tvb, offset+3, 2,
			    etype);
		}
		next_tvb = tvb_new_subset(tvb, offset+5, -1, -1);
		if (XDLC_IS_INFORMATION(control)) {
			if (subdissector_table != NULL) {
				/* do lookup with the subdissector table */
				if (dissector_try_port(subdissector_table,
				    etype, next_tvb, pinfo, tree))
					break;
			}
		}
		call_dissector(data_handle, next_tvb, pinfo, tree);
		break;
	}
}

void
proto_register_llc(void)
{
	static struct true_false_string ig_bit = { "Group", "Individual" };
	static struct true_false_string cr_bit = { "Response", "Command" };

	static hf_register_info hf[] = {
		{ &hf_llc_dsap,
		{ "DSAP",	"llc.dsap", FT_UINT8, BASE_HEX,
			VALS(sap_vals), 0x0, "", HFILL }},

		{ &hf_llc_dsap_ig,
		{ "IG Bit",	"llc.dsap.ig", FT_BOOLEAN, BASE_HEX,
			&ig_bit, 0x0, "Individual/Group", HFILL }},

		{ &hf_llc_ssap,
		{ "SSAP", "llc.ssap", FT_UINT8, BASE_HEX,
			VALS(sap_vals), 0x0, "", HFILL }},

		{ &hf_llc_ssap_cr,
		{ "CR Bit", "llc.ssap.cr", FT_BOOLEAN, BASE_HEX,
			&cr_bit, 0x0, "Command/Response", HFILL }},

		{ &hf_llc_ctrl,
		{ "Control", "llc.control", FT_UINT16, BASE_HEX,
			NULL, 0x0, "", HFILL }},

		/* registered here but handled in ethertype.c */
		{ &hf_llc_type,
		{ "Type", "llc.type", FT_UINT16, BASE_HEX,
			VALS(etype_vals), 0x0, "", HFILL }},

		{ &hf_llc_oui,
		{ "Organization Code",	"llc.oui", FT_UINT24, BASE_HEX,
			VALS(oui_vals), 0x0, "", HFILL }},

		{ &hf_llc_pid,
		{ "Protocol ID", "llc.pid", FT_UINT16, BASE_HEX,
			NULL, 0x0, "", HFILL }}
	};
	static gint *ett[] = {
		&ett_llc,
		&ett_llc_ctrl,
	};

	proto_llc = proto_register_protocol("Logical-Link Control", "LLC", "llc");
	proto_register_field_array(proto_llc, hf, array_length(hf));
	proto_register_subtree_array(ett, array_length(ett));

/* subdissector code */
	subdissector_table = register_dissector_table("llc.dsap",
	  "LLC SAP", FT_UINT8, BASE_HEX);
	xid_subdissector_table = register_dissector_table("llc.xid_dsap",
	  "LLC XID SAP", FT_UINT8, BASE_HEX);

	register_dissector("llc", dissect_llc, proto_llc);
}

static void
register_hf(gpointer key _U_, gpointer value, gpointer user_data _U_)
{
	oui_info_t *info = value;

	proto_register_field_array(proto_llc, info->field_info, 1);
}

void
proto_reg_handoff_llc(void)
{
	dissector_handle_t llc_handle;

	/*
	 * Get handles for the BPDU, Ethernet, FDDI, and Token Ring
	 * dissectors.
	 */
	bpdu_handle = find_dissector("bpdu");
	eth_handle = find_dissector("eth");
	fddi_handle = find_dissector("fddi");
	tr_handle = find_dissector("tr");
	data_handle = find_dissector("data");

	llc_handle = find_dissector("llc");
	dissector_add("wtap_encap", WTAP_ENCAP_ATM_RFC1483, llc_handle);
	/* RFC 2043 */
	dissector_add("ppp.protocol", PPP_LLC, llc_handle);
	/* RFC 2353 */
	dissector_add("udp.port", UDP_PORT_LLC1, llc_handle);
	dissector_add("udp.port", UDP_PORT_LLC2, llc_handle);
	dissector_add("udp.port", UDP_PORT_LLC3, llc_handle);
	dissector_add("udp.port", UDP_PORT_LLC4, llc_handle);
	dissector_add("udp.port", UDP_PORT_LLC5, llc_handle);
	/* IP-over-FC when we have the full FC frame */
	dissector_add("fc.ftype", FC_FTYPE_IP, llc_handle);

	/*
	 * BACNET-over-ARCNET is really BACNET-over-802.2 LLC-over-ARCNET,
	 * apparently.
	 */
	dissector_add("arcnet.protocol_id", ARCNET_PROTO_BACNET, llc_handle);

	/*
	 * Register all the fields for PIDs for various OUIs.
	 */
	g_hash_table_foreach(oui_info_table, register_hf, NULL);
}