summaryrefslogtreecommitdiffstats
path: root/freebsd/contrib/tcpdump/print-llc.c
blob: f8801d3927906839c98e0b8f0a73baee96546880 (plain) (blame)
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
#include <machine/rtems-bsd-user-space.h>

/*
 * Copyright (c) 1992, 1993, 1994, 1995, 1996, 1997
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that: (1) source code distributions
 * retain the above copyright notice and this paragraph in its entirety, (2)
 * distributions including binary code include the above copyright notice and
 * this paragraph in its entirety in the documentation or other materials
 * provided with the distribution, and (3) all advertising materials mentioning
 * features or use of this software display the following acknowledgement:
 * ``This product includes software developed by the University of California,
 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
 * the University nor the names of its contributors may be used to endorse
 * or promote products derived from this software without specific prior
 * written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 *
 * Code by Matt Thomas, Digital Equipment Corporation
 *	with an awful lot of hacking by Jeffrey Mogul, DECWRL
 *
 * $FreeBSD$
 */

#ifndef lint
static const char rcsid[] _U_ =
    "@(#) $Header: /tcpdump/master/tcpdump/print-llc.c,v 1.75 2007-04-13 09:43:11 hannes Exp $";
#endif

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

#include <tcpdump-stdinc.h>

#include <stdio.h>
#include <string.h>

#include "interface.h"
#include "addrtoname.h"
#include "extract.h"			/* must come after interface.h */

#include "llc.h"
#include "ethertype.h"
#include "oui.h"

static struct tok llc_values[] = {
        { LLCSAP_NULL,     "Null" },
        { LLCSAP_GLOBAL,   "Global" },
        { LLCSAP_8021B_I,  "802.1B I" },
        { LLCSAP_8021B_G,  "802.1B G" },
        { LLCSAP_IP,       "IP" },
        { LLCSAP_SNA,      "SNA" },
        { LLCSAP_PROWAYNM, "ProWay NM" },
        { LLCSAP_8021D,    "STP" },
        { LLCSAP_RS511,    "RS511" },
        { LLCSAP_ISO8208,  "ISO8208" },
        { LLCSAP_PROWAY,   "ProWay" },
        { LLCSAP_SNAP,     "SNAP" },
        { LLCSAP_IPX,      "IPX" },
        { LLCSAP_NETBEUI,  "NetBeui" },
        { LLCSAP_ISONS,    "OSI" },
        { 0,               NULL },
};

static struct tok llc_cmd_values[] = {
	{ LLC_UI,	"ui" },
	{ LLC_TEST,	"test" },
	{ LLC_XID,	"xid" },
	{ LLC_UA,	"ua" },
	{ LLC_DISC,	"disc" },
	{ LLC_DM,	"dm" },
	{ LLC_SABME,	"sabme" },
	{ LLC_FRMR,	"frmr" },
	{ 0,		NULL }
};

static const struct tok llc_flag_values[] = { 
        { 0, "Command" },
        { LLC_GSAP, "Response" },
        { LLC_U_POLL, "Poll" },
        { LLC_GSAP|LLC_U_POLL, "Final" },
        { LLC_IS_POLL, "Poll" },
        { LLC_GSAP|LLC_IS_POLL, "Final" },
	{ 0, NULL }
};


static const struct tok llc_ig_flag_values[] = { 
        { 0, "Individual" },
        { LLC_IG, "Group" },
	{ 0, NULL }
};


static const struct tok llc_supervisory_values[] = { 
        { 0, "Receiver Ready" },
        { 1, "Receiver not Ready" },
        { 2, "Reject" },
	{ 0,             NULL }
};


static const struct tok cisco_values[] = { 
	{ PID_CISCO_CDP, "CDP" },
	{ PID_CISCO_VTP, "VTP" },
	{ PID_CISCO_DTP, "DTP" },
	{ PID_CISCO_UDLD, "UDLD" },
	{ PID_CISCO_PVST, "PVST" },
	{ 0,             NULL }
};

static const struct tok bridged_values[] = { 
	{ PID_RFC2684_ETH_FCS,     "Ethernet + FCS" },
	{ PID_RFC2684_ETH_NOFCS,   "Ethernet w/o FCS" },
	{ PID_RFC2684_802_4_FCS,   "802.4 + FCS" },
	{ PID_RFC2684_802_4_NOFCS, "802.4 w/o FCS" },
	{ PID_RFC2684_802_5_FCS,   "Token Ring + FCS" },
	{ PID_RFC2684_802_5_NOFCS, "Token Ring w/o FCS" },
	{ PID_RFC2684_FDDI_FCS,    "FDDI + FCS" },
	{ PID_RFC2684_FDDI_NOFCS,  "FDDI w/o FCS" },
	{ PID_RFC2684_802_6_FCS,   "802.6 + FCS" },
	{ PID_RFC2684_802_6_NOFCS, "802.6 w/o FCS" },
	{ PID_RFC2684_BPDU,        "BPDU" },
	{ 0,                       NULL },
};

static const struct tok null_values[] = { 
	{ 0,             NULL }
};

struct oui_tok {
	u_int32_t	oui;
	const struct tok *tok;
};

static const struct oui_tok oui_to_tok[] = {
	{ OUI_ENCAP_ETHER, ethertype_values },
	{ OUI_CISCO_90, ethertype_values },	/* uses some Ethertype values */
	{ OUI_APPLETALK, ethertype_values },	/* uses some Ethertype values */
	{ OUI_CISCO, cisco_values },
	{ OUI_RFC2684, bridged_values },	/* bridged, RFC 2427 FR or RFC 2864 ATM */
	{ 0, NULL }
};

/*
 * Returns non-zero IFF it succeeds in printing the header
 */
int
llc_print(const u_char *p, u_int length, u_int caplen,
	  const u_char *esrc, const u_char *edst, u_short *extracted_ethertype)
{
	u_int8_t dsap_field, dsap, ssap_field, ssap;
	u_int16_t control;
	int is_u;
	register int ret;

	*extracted_ethertype = 0;

	if (caplen < 3) {
		(void)printf("[|llc]");
		default_print((u_char *)p, caplen);
		return(0);
	}

	dsap_field = *p;
	ssap_field = *(p + 1);

	/*
	 * OK, what type of LLC frame is this?  The length
	 * of the control field depends on that - I frames
	 * have a two-byte control field, and U frames have
	 * a one-byte control field.
	 */
	control = *(p + 2);
	if ((control & LLC_U_FMT) == LLC_U_FMT) {
		/*
		 * U frame.
		 */
		is_u = 1;
	} else {
		/*
		 * The control field in I and S frames is
		 * 2 bytes...
		 */
		if (caplen < 4) {
			(void)printf("[|llc]");
			default_print((u_char *)p, caplen);
			return(0);
		}

		/*
		 * ...and is little-endian.
		 */
		control = EXTRACT_LE_16BITS(p + 2);
		is_u = 0;
	}

	if (ssap_field == LLCSAP_GLOBAL && dsap_field == LLCSAP_GLOBAL) {
		/*
		 * This is an Ethernet_802.3 IPX frame; it has an
		 * 802.3 header (i.e., an Ethernet header where the
		 * type/length field is <= ETHERMTU, i.e. it's a length
		 * field, not a type field), but has no 802.2 header -
		 * the IPX packet starts right after the Ethernet header,
		 * with a signature of two bytes of 0xFF (which is
		 * LLCSAP_GLOBAL).
		 *
		 * (It might also have been an Ethernet_802.3 IPX at
		 * one time, but got bridged onto another network,
		 * such as an 802.11 network; this has appeared in at
		 * least one capture file.)
		 */

            if (eflag)
		printf("IPX 802.3: ");

            ipx_print(p, length);
            return (1);
	}

	dsap = dsap_field & ~LLC_IG;
	ssap = ssap_field & ~LLC_GSAP;

	if (eflag) {
                printf("LLC, dsap %s (0x%02x) %s, ssap %s (0x%02x) %s",
                       tok2str(llc_values, "Unknown", dsap),
                       dsap,
                       tok2str(llc_ig_flag_values, "Unknown", dsap_field & LLC_IG),
                       tok2str(llc_values, "Unknown", ssap),
                       ssap,
                       tok2str(llc_flag_values, "Unknown", ssap_field & LLC_GSAP));

		if (is_u) {
			printf(", ctrl 0x%02x: ", control);
		} else {
			printf(", ctrl 0x%04x: ", control);
		}
	}

	if (ssap == LLCSAP_8021D && dsap == LLCSAP_8021D &&
	    control == LLC_UI) {
		stp_print(p+3, length-3);
		return (1);
	}

	if (ssap == LLCSAP_IP && dsap == LLCSAP_IP &&
	    control == LLC_UI) {
		ip_print(gndo, p+4, length-4);
		return (1);
	}

	if (ssap == LLCSAP_IPX && dsap == LLCSAP_IPX &&
	    control == LLC_UI) {
		/*
		 * This is an Ethernet_802.2 IPX frame, with an 802.3
		 * header and an 802.2 LLC header with the source and
		 * destination SAPs being the IPX SAP.
		 *
		 * Skip DSAP, LSAP, and control field.
		 */
                if (eflag)
                        printf("IPX 802.2: ");

		ipx_print(p+3, length-3);
		return (1);
	}

#ifdef TCPDUMP_DO_SMB
	if (ssap == LLCSAP_NETBEUI && dsap == LLCSAP_NETBEUI
	    && (!(control & LLC_S_FMT) || control == LLC_U_FMT)) {
		/*
		 * we don't actually have a full netbeui parser yet, but the
		 * smb parser can handle many smb-in-netbeui packets, which
		 * is very useful, so we call that
		 *
		 * We don't call it for S frames, however, just I frames
		 * (which are frames that don't have the low-order bit,
		 * LLC_S_FMT, set in the first byte of the control field)
		 * and UI frames (whose control field is just 3, LLC_U_FMT).
		 */

		/*
		 * Skip the LLC header.
		 */
		if (is_u) {
			p += 3;
			length -= 3;
			caplen -= 3;
		} else {
			p += 4;
			length -= 4;
			caplen -= 4;
		}
		netbeui_print(control, p, length);
		return (1);
	}
#endif
	if (ssap == LLCSAP_ISONS && dsap == LLCSAP_ISONS
	    && control == LLC_UI) {
		isoclns_print(p + 3, length - 3, caplen - 3);
		return (1);
	}

	if (ssap == LLCSAP_SNAP && dsap == LLCSAP_SNAP
	    && control == LLC_UI) {
		/*
		 * XXX - what *is* the right bridge pad value here?
		 * Does anybody ever bridge one form of LAN traffic
		 * over a networking type that uses 802.2 LLC?
		 */
		ret = snap_print(p+3, length-3, caplen-3, 2);
		if (ret)
			return (ret);
	}

	if (!eflag) {
		if (ssap == dsap) {
			if (esrc == NULL || edst == NULL)
				(void)printf("%s ", tok2str(llc_values, "Unknown DSAP 0x%02x", dsap));
			else
				(void)printf("%s > %s %s ",
						etheraddr_string(esrc),
						etheraddr_string(edst),
						tok2str(llc_values, "Unknown DSAP 0x%02x", dsap));
		} else {
			if (esrc == NULL || edst == NULL)
				(void)printf("%s > %s ",
                                        tok2str(llc_values, "Unknown SSAP 0x%02x", ssap),
					tok2str(llc_values, "Unknown DSAP 0x%02x", dsap));
			else
				(void)printf("%s %s > %s %s ",
					etheraddr_string(esrc),
                                        tok2str(llc_values, "Unknown SSAP 0x%02x", ssap),
					etheraddr_string(edst),
					tok2str(llc_values, "Unknown DSAP 0x%02x", dsap));
		}
	}

	if (is_u) {
		printf("Unnumbered, %s, Flags [%s], length %u",
                       tok2str(llc_cmd_values, "%02x", LLC_U_CMD(control)),
                       tok2str(llc_flag_values,"?",(ssap_field & LLC_GSAP) | (control & LLC_U_POLL)),
                       length);

		p += 3;
		length -= 3;
		caplen -= 3;

		if ((control & ~LLC_U_POLL) == LLC_XID) {
			if (*p == LLC_XID_FI) {
				printf(": %02x %02x", p[1], p[2]);
				p += 3;
				length -= 3;
				caplen -= 3;
			}
		}
	} else {
		if ((control & LLC_S_FMT) == LLC_S_FMT) {
			(void)printf("Supervisory, %s, rcv seq %u, Flags [%s], length %u",
				tok2str(llc_supervisory_values,"?",LLC_S_CMD(control)),
				LLC_IS_NR(control),
				tok2str(llc_flag_values,"?",(ssap_field & LLC_GSAP) | (control & LLC_IS_POLL)),
                                length);
		} else {
			(void)printf("Information, send seq %u, rcv seq %u, Flags [%s], length %u",
				LLC_I_NS(control),
				LLC_IS_NR(control),
				tok2str(llc_flag_values,"?",(ssap_field & LLC_GSAP) | (control & LLC_IS_POLL)),
                                length);
		}
		p += 4;
		length -= 4;
		caplen -= 4;
	}
	return(1);
}

int
snap_print(const u_char *p, u_int length, u_int caplen, u_int bridge_pad)
{
	u_int32_t orgcode;
	register u_short et;
	register int ret;

	TCHECK2(*p, 5);
	orgcode = EXTRACT_24BITS(p);
	et = EXTRACT_16BITS(p + 3);

	if (eflag) {
		const struct tok *tok = null_values;
		const struct oui_tok *otp;

		for (otp = &oui_to_tok[0]; otp->tok != NULL; otp++) {
			if (otp->oui == orgcode) {
				tok = otp->tok;
				break;
			}
		}
		(void)printf("oui %s (0x%06x), %s %s (0x%04x): ",
		     tok2str(oui_values, "Unknown", orgcode),
		     orgcode,
		     (orgcode == 0x000000 ? "ethertype" : "pid"),
		     tok2str(tok, "Unknown", et),
		     et);
	}
	p += 5;
	length -= 5;
	caplen -= 5;

	switch (orgcode) {
	case OUI_ENCAP_ETHER:
	case OUI_CISCO_90:
		/*
		 * This is an encapsulated Ethernet packet,
		 * or a packet bridged by some piece of
		 * Cisco hardware; the protocol ID is
		 * an Ethernet protocol type.
		 */
		ret = ethertype_print(gndo, et, p, length, caplen);
		if (ret)
			return (ret);
		break;

	case OUI_APPLETALK:
		if (et == ETHERTYPE_ATALK) {
			/*
			 * No, I have no idea why Apple used one
			 * of their own OUIs, rather than
			 * 0x000000, and an Ethernet packet
			 * type, for Appletalk data packets,
			 * but used 0x000000 and an Ethernet
			 * packet type for AARP packets.
			 */
			ret = ethertype_print(gndo, et, p, length, caplen);
			if (ret)
				return (ret);
		}
		break;

	case OUI_CISCO:
                switch (et) {
                case PID_CISCO_CDP:
                        cdp_print(p, length, caplen);
                        return (1);
                case PID_CISCO_DTP:
                        dtp_print(p, length); 
                        return (1);
                case PID_CISCO_UDLD:
                        udld_print(p, length);
                        return (1);
                case PID_CISCO_VTP:
                        vtp_print(p, length);
                        return (1);
                case PID_CISCO_PVST:
                        stp_print(p, length);
                        return (1);
                default:
                        break;
                }

	case OUI_RFC2684:
		switch (et) {

		case PID_RFC2684_ETH_FCS:
		case PID_RFC2684_ETH_NOFCS:
			/*
			 * XXX - remove the last two bytes for
			 * PID_RFC2684_ETH_FCS?
			 */
			/*
			 * Skip the padding.
			 */
			TCHECK2(*p, bridge_pad);
			caplen -= bridge_pad;
			length -= bridge_pad;
			p += bridge_pad;

			/*
			 * What remains is an Ethernet packet.
			 */
			ether_print(gndo, p, length, caplen, NULL, NULL);
			return (1);

		case PID_RFC2684_802_5_FCS:
		case PID_RFC2684_802_5_NOFCS:
			/*
			 * XXX - remove the last two bytes for
			 * PID_RFC2684_ETH_FCS?
			 */
			/*
			 * Skip the padding, but not the Access
			 * Control field.
			 */
			TCHECK2(*p, bridge_pad);
			caplen -= bridge_pad;
			length -= bridge_pad;
			p += bridge_pad;

			/*
			 * What remains is an 802.5 Token Ring
			 * packet.
			 */
			token_print(p, length, caplen);
			return (1);

		case PID_RFC2684_FDDI_FCS:
		case PID_RFC2684_FDDI_NOFCS:
			/*
			 * XXX - remove the last two bytes for
			 * PID_RFC2684_ETH_FCS?
			 */
			/*
			 * Skip the padding.
			 */
			TCHECK2(*p, bridge_pad + 1);
			caplen -= bridge_pad + 1;
			length -= bridge_pad + 1;
			p += bridge_pad + 1;

			/*
			 * What remains is an FDDI packet.
			 */
			fddi_print(p, length, caplen);
			return (1);

		case PID_RFC2684_BPDU:
			stp_print(p, length);
			return (1);
		}
	}
	return (0);

trunc:
	(void)printf("[|snap]");
	return (1);
}


/*
 * Local Variables:
 * c-style: whitesmith
 * c-basic-offset: 8
 * End:
 */