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1 /*
2 * Copyright (c) 1993, 1994, 1995, 1996, 1997
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that: (1) source code distributions
7 * retain the above copyright notice and this paragraph in its entirety, (2)
8 * distributions including binary code include the above copyright notice and
9 * this paragraph in its entirety in the documentation or other materials
10 * provided with the distribution, and (3) all advertising materials mentioning
11 * features or use of this software display the following acknowledgement:
12 * ``This product includes software developed by the University of California,
13 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
14 * the University nor the names of its contributors may be used to endorse
15 * or promote products derived from this software without specific prior
16 * written permission.
17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
18 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
20 *
21 * pcap-common.c - common code for pcap and pcap-ng files
22 */
23
24 #ifdef HAVE_CONFIG_H
25 #include "config.h"
26 #endif
27
28 #ifdef WIN32
29 #include <pcap-stdinc.h>
30 #else /* WIN32 */
31 #if HAVE_INTTYPES_H
32 #include <inttypes.h>
33 #elif HAVE_STDINT_H
34 #include <stdint.h>
35 #endif
36 #ifdef HAVE_SYS_BITYPES_H
37 #include <sys/bitypes.h>
38 #endif
39 #include <sys/types.h>
40 #endif /* WIN32 */
41
42 #include "pcap-int.h"
43 #include "pcap/usb.h"
44
45 #include "pcap-common.h"
46
47 /*
48 * We don't write DLT_* values to capture files, because they're not the
49 * same on all platforms.
50 *
51 * Unfortunately, the various flavors of BSD have not always used the same
52 * numerical values for the same data types, and various patches to
53 * libpcap for non-BSD OSes have added their own DLT_* codes for link
54 * layer encapsulation types seen on those OSes, and those codes have had,
55 * in some cases, values that were also used, on other platforms, for other
56 * link layer encapsulation types.
57 *
58 * This means that capture files of a type whose numerical DLT_* code
59 * means different things on different BSDs, or with different versions
60 * of libpcap, can't always be read on systems other than those like
61 * the one running on the machine on which the capture was made.
62 *
63 * Instead, we define here a set of LINKTYPE_* codes, and map DLT_* codes
64 * to LINKTYPE_* codes when writing a savefile header, and map LINKTYPE_*
65 * codes to DLT_* codes when reading a savefile header.
66 *
67 * For those DLT_* codes that have, as far as we know, the same values on
68 * all platforms (DLT_NULL through DLT_FDDI), we define LINKTYPE_xxx as
69 * DLT_xxx; that way, captures of those types can still be read by
70 * versions of libpcap that map LINKTYPE_* values to DLT_* values, and
71 * captures of those types written by versions of libpcap that map DLT_
72 * values to LINKTYPE_ values can still be read by older versions
73 * of libpcap.
74 *
75 * The other LINKTYPE_* codes are given values starting at 100, in the
76 * hopes that no DLT_* code will be given one of those values.
77 *
78 * In order to ensure that a given LINKTYPE_* code's value will refer to
79 * the same encapsulation type on all platforms, you should not allocate
80 * a new LINKTYPE_* value without consulting
81 * "tcpdump-workers@lists.tcpdump.org". The tcpdump developers will
82 * allocate a value for you, and will not subsequently allocate it to
83 * anybody else; that value will be added to the "pcap.h" in the
84 * tcpdump.org Git repository, so that a future libpcap release will
85 * include it.
86 *
87 * You should, if possible, also contribute patches to libpcap and tcpdump
88 * to handle the new encapsulation type, so that they can also be checked
89 * into the tcpdump.org Git repository and so that they will appear in
90 * future libpcap and tcpdump releases.
91 *
92 * Do *NOT* assume that any values after the largest value in this file
93 * are available; you might not have the most up-to-date version of this
94 * file, and new values after that one might have been assigned. Also,
95 * do *NOT* use any values below 100 - those might already have been
96 * taken by one (or more!) organizations.
97 *
98 * Any platform that defines additional DLT_* codes should:
99 *
100 * request a LINKTYPE_* code and value from tcpdump.org,
101 * as per the above;
102 *
103 * add, in their version of libpcap, an entry to map
104 * those DLT_* codes to the corresponding LINKTYPE_*
105 * code;
106 *
107 * redefine, in their "net/bpf.h", any DLT_* values
108 * that collide with the values used by their additional
109 * DLT_* codes, to remove those collisions (but without
110 * making them collide with any of the LINKTYPE_*
111 * values equal to 50 or above; they should also avoid
112 * defining DLT_* values that collide with those
113 * LINKTYPE_* values, either).
114 */
115 #define LINKTYPE_NULL DLT_NULL
116 #define LINKTYPE_ETHERNET DLT_EN10MB /* also for 100Mb and up */
117 #define LINKTYPE_EXP_ETHERNET DLT_EN3MB /* 3Mb experimental Ethernet */
118 #define LINKTYPE_AX25 DLT_AX25
119 #define LINKTYPE_PRONET DLT_PRONET
120 #define LINKTYPE_CHAOS DLT_CHAOS
121 #define LINKTYPE_IEEE802_5 DLT_IEEE802 /* DLT_IEEE802 is used for 802.5 Token Ring */
122 #define LINKTYPE_ARCNET_BSD DLT_ARCNET /* BSD-style headers */
123 #define LINKTYPE_SLIP DLT_SLIP
124 #define LINKTYPE_PPP DLT_PPP
125 #define LINKTYPE_FDDI DLT_FDDI
126
127 /*
128 * LINKTYPE_PPP is for use when there might, or might not, be an RFC 1662
129 * PPP in HDLC-like framing header (with 0xff 0x03 before the PPP protocol
130 * field) at the beginning of the packet.
131 *
132 * This is for use when there is always such a header; the address field
133 * might be 0xff, for regular PPP, or it might be an address field for Cisco
134 * point-to-point with HDLC framing as per section 4.3.1 of RFC 1547 ("Cisco
135 * HDLC"). This is, for example, what you get with NetBSD's DLT_PPP_SERIAL.
136 *
137 * We give it the same value as NetBSD's DLT_PPP_SERIAL, in the hopes that
138 * nobody else will choose a DLT_ value of 50, and so that DLT_PPP_SERIAL
139 * captures will be written out with a link type that NetBSD's tcpdump
140 * can read.
141 */
142 #define LINKTYPE_PPP_HDLC 50 /* PPP in HDLC-like framing */
143
144 #define LINKTYPE_PPP_ETHER 51 /* NetBSD PPP-over-Ethernet */
145
146 #define LINKTYPE_SYMANTEC_FIREWALL 99 /* Symantec Enterprise Firewall */
147
148 /*
149 * These correspond to DLT_s that have different values on different
150 * platforms; we map between these values in capture files and
151 * the DLT_ values as returned by pcap_datalink() and passed to
152 * pcap_open_dead().
153 */
154 #define LINKTYPE_ATM_RFC1483 100 /* LLC/SNAP-encapsulated ATM */
155 #define LINKTYPE_RAW 101 /* raw IP */
156 #define LINKTYPE_SLIP_BSDOS 102 /* BSD/OS SLIP BPF header */
157 #define LINKTYPE_PPP_BSDOS 103 /* BSD/OS PPP BPF header */
158
159 /*
160 * Values starting with 104 are used for newly-assigned link-layer
161 * header type values; for those link-layer header types, the DLT_
162 * value returned by pcap_datalink() and passed to pcap_open_dead(),
163 * and the LINKTYPE_ value that appears in capture files, are the
164 * same.
165 *
166 * LINKTYPE_MATCHING_MIN is the lowest such value; LINKTYPE_MATCHING_MAX
167 * is the highest such value.
168 */
169 #define LINKTYPE_MATCHING_MIN 104 /* lowest value in the "matching" range */
170
171 #define LINKTYPE_C_HDLC 104 /* Cisco HDLC */
172 #define LINKTYPE_IEEE802_11 105 /* IEEE 802.11 (wireless) */
173 #define LINKTYPE_ATM_CLIP 106 /* Linux Classical IP over ATM */
174 #define LINKTYPE_FRELAY 107 /* Frame Relay */
175 #define LINKTYPE_LOOP 108 /* OpenBSD loopback */
176 #define LINKTYPE_ENC 109 /* OpenBSD IPSEC enc */
177
178 /*
179 * These three types are reserved for future use.
180 */
181 #define LINKTYPE_LANE8023 110 /* ATM LANE + 802.3 */
182 #define LINKTYPE_HIPPI 111 /* NetBSD HIPPI */
183 #define LINKTYPE_HDLC 112 /* NetBSD HDLC framing */
184
185 #define LINKTYPE_LINUX_SLL 113 /* Linux cooked socket capture */
186 #define LINKTYPE_LTALK 114 /* Apple LocalTalk hardware */
187 #define LINKTYPE_ECONET 115 /* Acorn Econet */
188
189 /*
190 * Reserved for use with OpenBSD ipfilter.
191 */
192 #define LINKTYPE_IPFILTER 116
193
194 #define LINKTYPE_PFLOG 117 /* OpenBSD DLT_PFLOG */
195 #define LINKTYPE_CISCO_IOS 118 /* For Cisco-internal use */
196 #define LINKTYPE_IEEE802_11_PRISM 119 /* 802.11 plus Prism II monitor mode radio metadata header */
197 #define LINKTYPE_IEEE802_11_AIRONET 120 /* 802.11 plus FreeBSD Aironet driver radio metadata header */
198
199 /*
200 * Reserved for Siemens HiPath HDLC.
201 */
202 #define LINKTYPE_HHDLC 121
203
204 #define LINKTYPE_IP_OVER_FC 122 /* RFC 2625 IP-over-Fibre Channel */
205 #define LINKTYPE_SUNATM 123 /* Solaris+SunATM */
206
207 /*
208 * Reserved as per request from Kent Dahlgren <kent@praesum.com>
209 * for private use.
210 */
211 #define LINKTYPE_RIO 124 /* RapidIO */
212 #define LINKTYPE_PCI_EXP 125 /* PCI Express */
213 #define LINKTYPE_AURORA 126 /* Xilinx Aurora link layer */
214
215 #define LINKTYPE_IEEE802_11_RADIOTAP 127 /* 802.11 plus radiotap radio metadata header */
216
217 /*
218 * Reserved for the TZSP encapsulation, as per request from
219 * Chris Waters <chris.waters@networkchemistry.com>
220 * TZSP is a generic encapsulation for any other link type,
221 * which includes a means to include meta-information
222 * with the packet, e.g. signal strength and channel
223 * for 802.11 packets.
224 */
225 #define LINKTYPE_TZSP 128 /* Tazmen Sniffer Protocol */
226
227 #define LINKTYPE_ARCNET_LINUX 129 /* Linux-style headers */
228
229 /*
230 * Juniper-private data link types, as per request from
231 * Hannes Gredler <hannes@juniper.net>. The corresponding
232 * DLT_s are used for passing on chassis-internal
233 * metainformation such as QOS profiles, etc..
234 */
235 #define LINKTYPE_JUNIPER_MLPPP 130
236 #define LINKTYPE_JUNIPER_MLFR 131
237 #define LINKTYPE_JUNIPER_ES 132
238 #define LINKTYPE_JUNIPER_GGSN 133
239 #define LINKTYPE_JUNIPER_MFR 134
240 #define LINKTYPE_JUNIPER_ATM2 135
241 #define LINKTYPE_JUNIPER_SERVICES 136
242 #define LINKTYPE_JUNIPER_ATM1 137
243
244 #define LINKTYPE_APPLE_IP_OVER_IEEE1394 138 /* Apple IP-over-IEEE 1394 cooked header */
245
246 #define LINKTYPE_MTP2_WITH_PHDR 139
247 #define LINKTYPE_MTP2 140
248 #define LINKTYPE_MTP3 141
249 #define LINKTYPE_SCCP 142
250
251 #define LINKTYPE_DOCSIS 143 /* DOCSIS MAC frames */
252
253 #define LINKTYPE_LINUX_IRDA 144 /* Linux-IrDA */
254
255 /*
256 * Reserved for IBM SP switch and IBM Next Federation switch.
257 */
258 #define LINKTYPE_IBM_SP 145
259 #define LINKTYPE_IBM_SN 146
260
261 /*
262 * Reserved for private use. If you have some link-layer header type
263 * that you want to use within your organization, with the capture files
264 * using that link-layer header type not ever be sent outside your
265 * organization, you can use these values.
266 *
267 * No libpcap release will use these for any purpose, nor will any
268 * tcpdump release use them, either.
269 *
270 * Do *NOT* use these in capture files that you expect anybody not using
271 * your private versions of capture-file-reading tools to read; in
272 * particular, do *NOT* use them in products, otherwise you may find that
273 * people won't be able to use tcpdump, or snort, or Ethereal, or... to
274 * read capture files from your firewall/intrusion detection/traffic
275 * monitoring/etc. appliance, or whatever product uses that LINKTYPE_ value,
276 * and you may also find that the developers of those applications will
277 * not accept patches to let them read those files.
278 *
279 * Also, do not use them if somebody might send you a capture using them
280 * for *their* private type and tools using them for *your* private type
281 * would have to read them.
282 *
283 * Instead, in those cases, ask "tcpdump-workers@lists.tcpdump.org" for a
284 * new DLT_ and LINKTYPE_ value, as per the comment in pcap/bpf.h, and use
285 * the type you're given.
286 */
287 #define LINKTYPE_USER0 147
288 #define LINKTYPE_USER1 148
289 #define LINKTYPE_USER2 149
290 #define LINKTYPE_USER3 150
291 #define LINKTYPE_USER4 151
292 #define LINKTYPE_USER5 152
293 #define LINKTYPE_USER6 153
294 #define LINKTYPE_USER7 154
295 #define LINKTYPE_USER8 155
296 #define LINKTYPE_USER9 156
297 #define LINKTYPE_USER10 157
298 #define LINKTYPE_USER11 158
299 #define LINKTYPE_USER12 159
300 #define LINKTYPE_USER13 160
301 #define LINKTYPE_USER14 161
302 #define LINKTYPE_USER15 162
303
304 /*
305 * For future use with 802.11 captures - defined by AbsoluteValue
306 * Systems to store a number of bits of link-layer information
307 * including radio information:
308 *
309 * http://www.shaftnet.org/~pizza/software/capturefrm.txt
310 */
311 #define LINKTYPE_IEEE802_11_AVS 163 /* 802.11 plus AVS radio metadata header */
312
313 /*
314 * Juniper-private data link type, as per request from
315 * Hannes Gredler <hannes@juniper.net>. The corresponding
316 * DLT_s are used for passing on chassis-internal
317 * metainformation such as QOS profiles, etc..
318 */
319 #define LINKTYPE_JUNIPER_MONITOR 164
320
321 /*
322 * BACnet MS/TP frames.
323 */
324 #define LINKTYPE_BACNET_MS_TP 165
325
326 /*
327 * Another PPP variant as per request from Karsten Keil <kkeil@suse.de>.
328 *
329 * This is used in some OSes to allow a kernel socket filter to distinguish
330 * between incoming and outgoing packets, on a socket intended to
331 * supply pppd with outgoing packets so it can do dial-on-demand and
332 * hangup-on-lack-of-demand; incoming packets are filtered out so they
333 * don't cause pppd to hold the connection up (you don't want random
334 * input packets such as port scans, packets from old lost connections,
335 * etc. to force the connection to stay up).
336 *
337 * The first byte of the PPP header (0xff03) is modified to accomodate
338 * the direction - 0x00 = IN, 0x01 = OUT.
339 */
340 #define LINKTYPE_PPP_PPPD 166
341
342 /*
343 * Juniper-private data link type, as per request from
344 * Hannes Gredler <hannes@juniper.net>. The DLT_s are used
345 * for passing on chassis-internal metainformation such as
346 * QOS profiles, cookies, etc..
347 */
348 #define LINKTYPE_JUNIPER_PPPOE 167
349 #define LINKTYPE_JUNIPER_PPPOE_ATM 168
350
351 #define LINKTYPE_GPRS_LLC 169 /* GPRS LLC */
352 #define LINKTYPE_GPF_T 170 /* GPF-T (ITU-T G.7041/Y.1303) */
353 #define LINKTYPE_GPF_F 171 /* GPF-T (ITU-T G.7041/Y.1303) */
354
355 /*
356 * Requested by Oolan Zimmer <oz@gcom.com> for use in Gcom's T1/E1 line
357 * monitoring equipment.
358 */
359 #define LINKTYPE_GCOM_T1E1 172
360 #define LINKTYPE_GCOM_SERIAL 173
361
362 /*
363 * Juniper-private data link type, as per request from
364 * Hannes Gredler <hannes@juniper.net>. The DLT_ is used
365 * for internal communication to Physical Interface Cards (PIC)
366 */
367 #define LINKTYPE_JUNIPER_PIC_PEER 174
368
369 /*
370 * Link types requested by Gregor Maier <gregor@endace.com> of Endace
371 * Measurement Systems. They add an ERF header (see
372 * http://www.endace.com/support/EndaceRecordFormat.pdf) in front of
373 * the link-layer header.
374 */
375 #define LINKTYPE_ERF_ETH 175 /* Ethernet */
376 #define LINKTYPE_ERF_POS 176 /* Packet-over-SONET */
377
378 /*
379 * Requested by Daniele Orlandi <daniele@orlandi.com> for raw LAPD
380 * for vISDN (http://www.orlandi.com/visdn/). Its link-layer header
381 * includes additional information before the LAPD header, so it's
382 * not necessarily a generic LAPD header.
383 */
384 #define LINKTYPE_LINUX_LAPD 177
385
386 /*
387 * Juniper-private data link type, as per request from
388 * Hannes Gredler <hannes@juniper.net>.
389 * The Link Types are used for prepending meta-information
390 * like interface index, interface name
391 * before standard Ethernet, PPP, Frelay & C-HDLC Frames
392 */
393 #define LINKTYPE_JUNIPER_ETHER 178
394 #define LINKTYPE_JUNIPER_PPP 179
395 #define LINKTYPE_JUNIPER_FRELAY 180
396 #define LINKTYPE_JUNIPER_CHDLC 181
397
398 /*
399 * Multi Link Frame Relay (FRF.16)
400 */
401 #define LINKTYPE_MFR 182
402
403 /*
404 * Juniper-private data link type, as per request from
405 * Hannes Gredler <hannes@juniper.net>.
406 * The DLT_ is used for internal communication with a
407 * voice Adapter Card (PIC)
408 */
409 #define LINKTYPE_JUNIPER_VP 183
410
411 /*
412 * Arinc 429 frames.
413 * DLT_ requested by Gianluca Varenni <gianluca.varenni@cacetech.com>.
414 * Every frame contains a 32bit A429 label.
415 * More documentation on Arinc 429 can be found at
416 * http://www.condoreng.com/support/downloads/tutorials/ARINCTutorial.pdf
417 */
418 #define LINKTYPE_A429 184
419
420 /*
421 * Arinc 653 Interpartition Communication messages.
422 * DLT_ requested by Gianluca Varenni <gianluca.varenni@cacetech.com>.
423 * Please refer to the A653-1 standard for more information.
424 */
425 #define LINKTYPE_A653_ICM 185
426
427 /*
428 * USB packets, beginning with a USB setup header; requested by
429 * Paolo Abeni <paolo.abeni@email.it>.
430 */
431 #define LINKTYPE_USB 186
432
433 /*
434 * Bluetooth HCI UART transport layer (part H:4); requested by
435 * Paolo Abeni.
436 */
437 #define LINKTYPE_BLUETOOTH_HCI_H4 187
438
439 /*
440 * IEEE 802.16 MAC Common Part Sublayer; requested by Maria Cruz
441 * <cruz_petagay@bah.com>.
442 */
443 #define LINKTYPE_IEEE802_16_MAC_CPS 188
444
445 /*
446 * USB packets, beginning with a Linux USB header; requested by
447 * Paolo Abeni <paolo.abeni@email.it>.
448 */
449 #define LINKTYPE_USB_LINUX 189
450
451 /*
452 * Controller Area Network (CAN) v. 2.0B packets.
453 * DLT_ requested by Gianluca Varenni <gianluca.varenni@cacetech.com>.
454 * Used to dump CAN packets coming from a CAN Vector board.
455 * More documentation on the CAN v2.0B frames can be found at
456 * http://www.can-cia.org/downloads/?269
457 */
458 #define LINKTYPE_CAN20B 190
459
460 /*
461 * IEEE 802.15.4, with address fields padded, as is done by Linux
462 * drivers; requested by Juergen Schimmer.
463 */
464 #define LINKTYPE_IEEE802_15_4_LINUX 191
465
466 /*
467 * Per Packet Information encapsulated packets.
468 * LINKTYPE_ requested by Gianluca Varenni <gianluca.varenni@cacetech.com>.
469 */
470 #define LINKTYPE_PPI 192
471
472 /*
473 * Header for 802.16 MAC Common Part Sublayer plus a radiotap radio header;
474 * requested by Charles Clancy.
475 */
476 #define LINKTYPE_IEEE802_16_MAC_CPS_RADIO 193
477
478 /*
479 * Juniper-private data link type, as per request from
480 * Hannes Gredler <hannes@juniper.net>.
481 * The DLT_ is used for internal communication with a
482 * integrated service module (ISM).
483 */
484 #define LINKTYPE_JUNIPER_ISM 194
485
486 /*
487 * IEEE 802.15.4, exactly as it appears in the spec (no padding, no
488 * nothing); requested by Mikko Saarnivala <mikko.saarnivala@sensinode.com>.
489 */
490 #define LINKTYPE_IEEE802_15_4 195
491
492 /*
493 * Various link-layer types, with a pseudo-header, for SITA
494 * (http://www.sita.aero/); requested by Fulko Hew (fulko.hew@gmail.com).
495 */
496 #define LINKTYPE_SITA 196
497
498 /*
499 * Various link-layer types, with a pseudo-header, for Endace DAG cards;
500 * encapsulates Endace ERF records. Requested by Stephen Donnelly
501 * <stephen@endace.com>.
502 */
503 #define LINKTYPE_ERF 197
504
505 /*
506 * Special header prepended to Ethernet packets when capturing from a
507 * u10 Networks board. Requested by Phil Mulholland
508 * <phil@u10networks.com>.
509 */
510 #define LINKTYPE_RAIF1 198
511
512 /*
513 * IPMB packet for IPMI, beginning with the I2C slave address, followed
514 * by the netFn and LUN, etc.. Requested by Chanthy Toeung
515 * <chanthy.toeung@ca.kontron.com>.
516 */
517 #define LINKTYPE_IPMB 199
518
519 /*
520 * Juniper-private data link type, as per request from
521 * Hannes Gredler <hannes@juniper.net>.
522 * The DLT_ is used for capturing data on a secure tunnel interface.
523 */
524 #define LINKTYPE_JUNIPER_ST 200
525
526 /*
527 * Bluetooth HCI UART transport layer (part H:4), with pseudo-header
528 * that includes direction information; requested by Paolo Abeni.
529 */
530 #define LINKTYPE_BLUETOOTH_HCI_H4_WITH_PHDR 201
531
532 /*
533 * AX.25 packet with a 1-byte KISS header; see
534 *
535 * http://www.ax25.net/kiss.htm
536 *
537 * as per Richard Stearn <richard@rns-stearn.demon.co.uk>.
538 */
539 #define LINKTYPE_AX25_KISS 202
540
541 /*
542 * LAPD packets from an ISDN channel, starting with the address field,
543 * with no pseudo-header.
544 * Requested by Varuna De Silva <varunax@gmail.com>.
545 */
546 #define LINKTYPE_LAPD 203
547
548 /*
549 * Variants of various link-layer headers, with a one-byte direction
550 * pseudo-header prepended - zero means "received by this host",
551 * non-zero (any non-zero value) means "sent by this host" - as per
552 * Will Barker <w.barker@zen.co.uk>.
553 */
554 #define LINKTYPE_PPP_WITH_DIR 204 /* PPP */
555 #define LINKTYPE_C_HDLC_WITH_DIR 205 /* Cisco HDLC */
556 #define LINKTYPE_FRELAY_WITH_DIR 206 /* Frame Relay */
557 #define LINKTYPE_LAPB_WITH_DIR 207 /* LAPB */
558
559 /*
560 * 208 is reserved for an as-yet-unspecified proprietary link-layer
561 * type, as requested by Will Barker.
562 */
563
564 /*
565 * IPMB with a Linux-specific pseudo-header; as requested by Alexey Neyman
566 * <avn@pigeonpoint.com>.
567 */
568 #define LINKTYPE_IPMB_LINUX 209
569
570 /*
571 * FlexRay automotive bus - http://www.flexray.com/ - as requested
572 * by Hannes Kaelber <hannes.kaelber@x2e.de>.
573 */
574 #define LINKTYPE_FLEXRAY 210
575
576 /*
577 * Media Oriented Systems Transport (MOST) bus for multimedia
578 * transport - http://www.mostcooperation.com/ - as requested
579 * by Hannes Kaelber <hannes.kaelber@x2e.de>.
580 */
581 #define LINKTYPE_MOST 211
582
583 /*
584 * Local Interconnect Network (LIN) bus for vehicle networks -
585 * http://www.lin-subbus.org/ - as requested by Hannes Kaelber
586 * <hannes.kaelber@x2e.de>.
587 */
588 #define LINKTYPE_LIN 212
589
590 /*
591 * X2E-private data link type used for serial line capture,
592 * as requested by Hannes Kaelber <hannes.kaelber@x2e.de>.
593 */
594 #define LINKTYPE_X2E_SERIAL 213
595
596 /*
597 * X2E-private data link type used for the Xoraya data logger
598 * family, as requested by Hannes Kaelber <hannes.kaelber@x2e.de>.
599 */
600 #define LINKTYPE_X2E_XORAYA 214
601
602 /*
603 * IEEE 802.15.4, exactly as it appears in the spec (no padding, no
604 * nothing), but with the PHY-level data for non-ASK PHYs (4 octets
605 * of 0 as preamble, one octet of SFD, one octet of frame length+
606 * reserved bit, and then the MAC-layer data, starting with the
607 * frame control field).
608 *
609 * Requested by Max Filippov <jcmvbkbc@gmail.com>.
610 */
611 #define LINKTYPE_IEEE802_15_4_NONASK_PHY 215
612
613 /*
614 * David Gibson <david@gibson.dropbear.id.au> requested this for
615 * captures from the Linux kernel /dev/input/eventN devices. This
616 * is used to communicate keystrokes and mouse movements from the
617 * Linux kernel to display systems, such as Xorg.
618 */
619 #define LINKTYPE_LINUX_EVDEV 216
620
621 /*
622 * GSM Um and Abis interfaces, preceded by a "gsmtap" header.
623 *
624 * Requested by Harald Welte <laforge@gnumonks.org>.
625 */
626 #define LINKTYPE_GSMTAP_UM 217
627 #define LINKTYPE_GSMTAP_ABIS 218
628
629 /*
630 * MPLS, with an MPLS label as the link-layer header.
631 * Requested by Michele Marchetto <michele@openbsd.org> on behalf
632 * of OpenBSD.
633 */
634 #define LINKTYPE_MPLS 219
635
636 /*
637 * USB packets, beginning with a Linux USB header, with the USB header
638 * padded to 64 bytes; required for memory-mapped access.
639 */
640 #define LINKTYPE_USB_LINUX_MMAPPED 220
641
642 /*
643 * DECT packets, with a pseudo-header; requested by
644 * Matthias Wenzel <tcpdump@mazzoo.de>.
645 */
646 #define LINKTYPE_DECT 221
647
648 /*
649 * From: "Lidwa, Eric (GSFC-582.0)[SGT INC]" <eric.lidwa-1@nasa.gov>
650 * Date: Mon, 11 May 2009 11:18:30 -0500
651 *
652 * DLT_AOS. We need it for AOS Space Data Link Protocol.
653 * I have already written dissectors for but need an OK from
654 * legal before I can submit a patch.
655 *
656 */
657 #define LINKTYPE_AOS 222
658
659 /*
660 * Wireless HART (Highway Addressable Remote Transducer)
661 * From the HART Communication Foundation
662 * IES/PAS 62591
663 *
664 * Requested by Sam Roberts <vieuxtech@gmail.com>.
665 */
666 #define LINKTYPE_WIHART 223
667
668 /*
669 * Fibre Channel FC-2 frames, beginning with a Frame_Header.
670 * Requested by Kahou Lei <kahou82@gmail.com>.
671 */
672 #define LINKTYPE_FC_2 224
673
674 /*
675 * Fibre Channel FC-2 frames, beginning with an encoding of the
676 * SOF, and ending with an encoding of the EOF.
677 *
678 * The encodings represent the frame delimiters as 4-byte sequences
679 * representing the corresponding ordered sets, with K28.5
680 * represented as 0xBC, and the D symbols as the corresponding
681 * byte values; for example, SOFi2, which is K28.5 - D21.5 - D1.2 - D21.2,
682 * is represented as 0xBC 0xB5 0x55 0x55.
683 *
684 * Requested by Kahou Lei <kahou82@gmail.com>.
685 */
686 #define LINKTYPE_FC_2_WITH_FRAME_DELIMS 225
687
688 /*
689 * Solaris ipnet pseudo-header; requested by Darren Reed <Darren.Reed@Sun.COM>.
690 *
691 * The pseudo-header starts with a one-byte version number; for version 2,
692 * the pseudo-header is:
693 *
694 * struct dl_ipnetinfo {
695 * u_int8_t dli_version;
696 * u_int8_t dli_family;
697 * u_int16_t dli_htype;
698 * u_int32_t dli_pktlen;
699 * u_int32_t dli_ifindex;
700 * u_int32_t dli_grifindex;
701 * u_int32_t dli_zsrc;
702 * u_int32_t dli_zdst;
703 * };
704 *
705 * dli_version is 2 for the current version of the pseudo-header.
706 *
707 * dli_family is a Solaris address family value, so it's 2 for IPv4
708 * and 26 for IPv6.
709 *
710 * dli_htype is a "hook type" - 0 for incoming packets, 1 for outgoing
711 * packets, and 2 for packets arriving from another zone on the same
712 * machine.
713 *
714 * dli_pktlen is the length of the packet data following the pseudo-header
715 * (so the captured length minus dli_pktlen is the length of the
716 * pseudo-header, assuming the entire pseudo-header was captured).
717 *
718 * dli_ifindex is the interface index of the interface on which the
719 * packet arrived.
720 *
721 * dli_grifindex is the group interface index number (for IPMP interfaces).
722 *
723 * dli_zsrc is the zone identifier for the source of the packet.
724 *
725 * dli_zdst is the zone identifier for the destination of the packet.
726 *
727 * A zone number of 0 is the global zone; a zone number of 0xffffffff
728 * means that the packet arrived from another host on the network, not
729 * from another zone on the same machine.
730 *
731 * An IPv4 or IPv6 datagram follows the pseudo-header; dli_family indicates
732 * which of those it is.
733 */
734 #define LINKTYPE_IPNET 226
735
736 /*
737 * CAN (Controller Area Network) frames, with a pseudo-header as supplied
738 * by Linux SocketCAN. See Documentation/networking/can.txt in the Linux
739 * source.
740 *
741 * Requested by Felix Obenhuber <felix@obenhuber.de>.
742 */
743 #define LINKTYPE_CAN_SOCKETCAN 227
744
745 /*
746 * Raw IPv4/IPv6; different from DLT_RAW in that the DLT_ value specifies
747 * whether it's v4 or v6. Requested by Darren Reed <Darren.Reed@Sun.COM>.
748 */
749 #define LINKTYPE_IPV4 228
750 #define LINKTYPE_IPV6 229
751
752 /*
753 * IEEE 802.15.4, exactly as it appears in the spec (no padding, no
754 * nothing), and with no FCS at the end of the frame; requested by
755 * Jon Smirl <jonsmirl@gmail.com>.
756 */
757 #define LINKTYPE_IEEE802_15_4_NOFCS 230
758
759 /*
760 * Raw D-Bus:
761 *
762 * http://www.freedesktop.org/wiki/Software/dbus
763 *
764 * messages:
765 *
766 * http://dbus.freedesktop.org/doc/dbus-specification.html#message-protocol-messages
767 *
768 * starting with the endianness flag, followed by the message type, etc.,
769 * but without the authentication handshake before the message sequence:
770 *
771 * http://dbus.freedesktop.org/doc/dbus-specification.html#auth-protocol
772 *
773 * Requested by Martin Vidner <martin@vidner.net>.
774 */
775 #define LINKTYPE_DBUS 231
776
777 /*
778 * Juniper-private data link type, as per request from
779 * Hannes Gredler <hannes@juniper.net>.
780 */
781 #define LINKTYPE_JUNIPER_VS 232
782 #define LINKTYPE_JUNIPER_SRX_E2E 233
783 #define LINKTYPE_JUNIPER_FIBRECHANNEL 234
784
785 /*
786 * DVB-CI (DVB Common Interface for communication between a PC Card
787 * module and a DVB receiver). See
788 *
789 * http://www.kaiser.cx/pcap-dvbci.html
790 *
791 * for the specification.
792 *
793 * Requested by Martin Kaiser <martin@kaiser.cx>.
794 */
795 #define LINKTYPE_DVB_CI 235
796
797 /*
798 * Variant of 3GPP TS 27.010 multiplexing protocol. Requested
799 * by Hans-Christoph Schemmel <hans-christoph.schemmel@cinterion.com>.
800 */
801 #define LINKTYPE_MUX27010 236
802
803 /*
804 * STANAG 5066 D_PDUs. Requested by M. Baris Demiray
805 * <barisdemiray@gmail.com>.
806 */
807 #define LINKTYPE_STANAG_5066_D_PDU 237
808
809 /*
810 * Juniper-private data link type, as per request from
811 * Hannes Gredler <hannes@juniper.net>.
812 */
813 #define LINKTYPE_JUNIPER_ATM_CEMIC 238
814
815 /*
816 * NetFilter LOG messages
817 * (payload of netlink NFNL_SUBSYS_ULOG/NFULNL_MSG_PACKET packets)
818 *
819 * Requested by Jakub Zawadzki <darkjames-ws@darkjames.pl>
820 */
821 #define LINKTYPE_NFLOG 239
822
823 /*
824 * Hilscher Gesellschaft fuer Systemautomation mbH link-layer type
825 * for Ethernet packets with a 4-byte pseudo-header and always
826 * with the payload including the FCS, as supplied by their
827 * netANALYZER hardware and software.
828 *
829 * Requested by Holger P. Frommer <HPfrommer@hilscher.com>
830 */
831 #define LINKTYPE_NETANALYZER 240
832
833 /*
834 * Hilscher Gesellschaft fuer Systemautomation mbH link-layer type
835 * for Ethernet packets with a 4-byte pseudo-header and FCS and
836 * 1 byte of SFD, as supplied by their netANALYZER hardware and
837 * software.
838 *
839 * Requested by Holger P. Frommer <HPfrommer@hilscher.com>
840 */
841 #define LINKTYPE_NETANALYZER_TRANSPARENT 241
842
843 /*
844 * IP-over-InfiniBand, as specified by RFC 4391.
845 *
846 * Requested by Petr Sumbera <petr.sumbera@oracle.com>.
847 */
848 #define LINKTYPE_IPOIB 242
849
850 /*
851 * MPEG-2 transport stream (ISO 13818-1/ITU-T H.222.0).
852 *
853 * Requested by Guy Martin <gmsoft@tuxicoman.be>.
854 */
855 #define LINKTYPE_MPEG_2_TS 243
856
857 /*
858 * ng4T GmbH's UMTS Iub/Iur-over-ATM and Iub/Iur-over-IP format as
859 * used by their ng40 protocol tester.
860 *
861 * Requested by Jens Grimmer <jens.grimmer@ng4t.com>.
862 */
863 #define LINKTYPE_NG40 244
864
865 /*
866 * Pseudo-header giving adapter number and flags, followed by an NFC
867 * (Near-Field Communications) Logical Link Control Protocol (LLCP) PDU,
868 * as specified by NFC Forum Logical Link Control Protocol Technical
869 * Specification LLCP 1.1.
870 *
871 * Requested by Mike Wakerly <mikey@google.com>.
872 */
873 #define LINKTYPE_NFC_LLCP 245
874
875 /*
876 * pfsync output; DLT_PFSYNC is 18, which collides with DLT_CIP in
877 * SuSE 6.3, on OpenBSD, NetBSD, DragonFly BSD, and Mac OS X, and
878 * is 121, which collides with DLT_HHDLC, in FreeBSD. We pick a
879 * shiny new link-layer header type value that doesn't collide with
880 * anything, in the hopes that future pfsync savefiles, if any,
881 * won't require special hacks to distinguish from other savefiles.
882 *
883 */
884 #define LINKTYPE_PFSYNC 246
885
886 /*
887 * Raw InfiniBand packets, starting with the Local Routing Header.
888 *
889 * Requested by Oren Kladnitsky <orenk@mellanox.com>.
890 */
891 #define LINKTYPE_INFINIBAND 247
892
893 /*
894 * SCTP, with no lower-level protocols (i.e., no IPv4 or IPv6).
895 *
896 * Requested by Michael Tuexen <Michael.Tuexen@lurchi.franken.de>.
897 */
898 #define LINKTYPE_SCTP 248
899
900 /*
901 * USB packets, beginning with a USBPcap header.
902 *
903 * Requested by Tomasz Mon <desowin@gmail.com>
904 */
905 #define LINKTYPE_USBPCAP 249
906
907 /*
908 * Schweitzer Engineering Laboratories "RTAC" product serial-line
909 * packets.
910 *
911 * Requested by Chris Bontje <chris_bontje@selinc.com>.
912 */
913 #define DLT_RTAC_SERIAL 250
914
915 /*
916 * Bluetooth Low Energy air interface link-layer packets.
917 *
918 * Requested by Mike Kershaw <dragorn@kismetwireless.net>.
919 */
920 #define LINKTYPE_BLUETOOTH_LE_LL 251
921
922 /*
923 * Link-layer header type for upper-protocol layer PDU saves from wireshark.
924 *
925 * the actual contents are determined by two TAGs stored with each
926 * packet:
927 * EXP_PDU_TAG_LINKTYPE the link type (LINKTYPE_ value) of the
928 * original packet.
929 *
930 * EXP_PDU_TAG_PROTO_NAME the name of the wireshark dissector
931 * that can make sense of the data stored.
932 */
933 #define LINKTYPE_WIRESHARK_UPPER_PDU 252
934
935 /*
936 * Link-layer header type for the netlink protocol (nlmon devices).
937 */
938 #define LINKTYPE_NETLINK 253
939
940 #define LINKTYPE_MATCHING_MAX 253 /* highest value in the "matching" range */
941
942 static struct linktype_map {
943 int dlt;
944 int linktype;
945 } map[] = {
946 /*
947 * These DLT_* codes have LINKTYPE_* codes with values identical
948 * to the values of the corresponding DLT_* code.
949 */
950 { DLT_NULL, LINKTYPE_NULL },
951 { DLT_EN10MB, LINKTYPE_ETHERNET },
952 { DLT_EN3MB, LINKTYPE_EXP_ETHERNET },
953 { DLT_AX25, LINKTYPE_AX25 },
954 { DLT_PRONET, LINKTYPE_PRONET },
955 { DLT_CHAOS, LINKTYPE_CHAOS },
956 { DLT_IEEE802, LINKTYPE_IEEE802_5 },
957 { DLT_ARCNET, LINKTYPE_ARCNET_BSD },
958 { DLT_SLIP, LINKTYPE_SLIP },
959 { DLT_PPP, LINKTYPE_PPP },
960 { DLT_FDDI, LINKTYPE_FDDI },
961 { DLT_SYMANTEC_FIREWALL, LINKTYPE_SYMANTEC_FIREWALL },
962
963 /*
964 * These DLT_* codes have different values on different
965 * platforms; we map them to LINKTYPE_* codes that
966 * have values that should never be equal to any DLT_*
967 * code.
968 */
969 #ifdef DLT_FR
970 /* BSD/OS Frame Relay */
971 { DLT_FR, LINKTYPE_FRELAY },
972 #endif
973
974 { DLT_ATM_RFC1483, LINKTYPE_ATM_RFC1483 },
975 { DLT_RAW, LINKTYPE_RAW },
976 { DLT_SLIP_BSDOS, LINKTYPE_SLIP_BSDOS },
977 { DLT_PPP_BSDOS, LINKTYPE_PPP_BSDOS },
978
979 /* BSD/OS Cisco HDLC */
980 { DLT_C_HDLC, LINKTYPE_C_HDLC },
981
982 /*
983 * These DLT_* codes are not on all platforms, but, so far,
984 * there don't appear to be any platforms that define
985 * other codes with those values; we map them to
986 * different LINKTYPE_* values anyway, just in case.
987 */
988
989 /* Linux ATM Classical IP */
990 { DLT_ATM_CLIP, LINKTYPE_ATM_CLIP },
991
992 /* NetBSD sync/async serial PPP (or Cisco HDLC) */
993 { DLT_PPP_SERIAL, LINKTYPE_PPP_HDLC },
994
995 /* NetBSD PPP over Ethernet */
996 { DLT_PPP_ETHER, LINKTYPE_PPP_ETHER },
997
998 /*
999 * All LINKTYPE_ values between LINKTYPE_MATCHING_MIN
1000 * and LINKTYPE_MATCHING_MAX are mapped to identical
1001 * DLT_ values.
1002 */
1003
1004 { -1, -1 }
1005 };
1006
1007 int
1008 dlt_to_linktype(int dlt)
1009 {
1010 int i;
1011
1012 /*
1013 * Map DLT_PFSYNC, whatever it might be, to LINKTYPE_PFSYNC.
1014 */
1015 if (dlt == DLT_PFSYNC)
1016 return (LINKTYPE_PFSYNC);
1017
1018 /*
1019 * Map the values in the matching range.
1020 */
1021 if (dlt >= DLT_MATCHING_MIN && dlt <= DLT_MATCHING_MAX)
1022 return (dlt);
1023
1024 /*
1025 * Map the values outside that range.
1026 */
1027 for (i = 0; map[i].dlt != -1; i++) {
1028 if (map[i].dlt == dlt)
1029 return (map[i].linktype);
1030 }
1031
1032 /*
1033 * If we don't have a mapping for this DLT_ code, return an
1034 * error; that means that this is a value with no corresponding
1035 * LINKTYPE_ code, and we need to assign one.
1036 */
1037 return (-1);
1038 }
1039
1040 int
1041 linktype_to_dlt(int linktype)
1042 {
1043 int i;
1044
1045 /*
1046 * Map LINKTYPE_PFSYNC to DLT_PFSYNC, whatever it might be.
1047 * LINKTYPE_PFSYNC is in the matching range, to make sure
1048 * it's as safe from reuse as we can arrange, so we do
1049 * this test first.
1050 */
1051 if (linktype == LINKTYPE_PFSYNC)
1052 return (DLT_PFSYNC);
1053
1054 /*
1055 * Map the values in the matching range.
1056 */
1057 if (linktype >= LINKTYPE_MATCHING_MIN &&
1058 linktype <= LINKTYPE_MATCHING_MAX)
1059 return (linktype);
1060
1061 /*
1062 * Map the values outside that range.
1063 */
1064 for (i = 0; map[i].linktype != -1; i++) {
1065 if (map[i].linktype == linktype)
1066 return (map[i].dlt);
1067 }
1068
1069 /*
1070 * If we don't have an entry for this link type, return
1071 * the link type value; it may be a DLT_ value from an
1072 * older version of libpcap.
1073 */
1074 return linktype;
1075 }
1076
1077 /*
1078 * The DLT_USB_LINUX and DLT_USB_LINUX_MMAPPED headers are in host
1079 * byte order when capturing (it's supplied directly from a
1080 * memory-mapped buffer shared by the kernel).
1081 *
1082 * When reading a DLT_USB_LINUX or DLT_USB_LINUX_MMAPPED capture file,
1083 * we need to convert it from the capturing host's byte order to
1084 * the reading host's byte order.
1085 */
1086 void
1087 swap_linux_usb_header(const struct pcap_pkthdr *hdr, u_char *buf,
1088 int header_len_64_bytes)
1089 {
1090 pcap_usb_header_mmapped *uhdr = (pcap_usb_header_mmapped *)buf;
1091 bpf_u_int32 offset = 0;
1092 usb_isodesc *pisodesc;
1093 int32_t numdesc, i;
1094
1095 /*
1096 * "offset" is the offset *past* the field we're swapping;
1097 * we skip the field *before* checking to make sure
1098 * the captured data length includes the entire field.
1099 */
1100
1101 /*
1102 * The URB id is a totally opaque value; do we really need to
1103 * convert it to the reading host's byte order???
1104 */
1105 offset += 8; /* skip past id */
1106 if (hdr->caplen < offset)
1107 return;
1108 uhdr->id = SWAPLL(uhdr->id);
1109
1110 offset += 4; /* skip past various 1-byte fields */
1111
1112 offset += 2; /* skip past bus_id */
1113 if (hdr->caplen < offset)
1114 return;
1115 uhdr->bus_id = SWAPSHORT(uhdr->bus_id);
1116
1117 offset += 2; /* skip past various 1-byte fields */
1118
1119 offset += 8; /* skip past ts_sec */
1120 if (hdr->caplen < offset)
1121 return;
1122 uhdr->ts_sec = SWAPLL(uhdr->ts_sec);
1123
1124 offset += 4; /* skip past ts_usec */
1125 if (hdr->caplen < offset)
1126 return;
1127 uhdr->ts_usec = SWAPLONG(uhdr->ts_usec);
1128
1129 offset += 4; /* skip past status */
1130 if (hdr->caplen < offset)
1131 return;
1132 uhdr->status = SWAPLONG(uhdr->status);
1133
1134 offset += 4; /* skip past urb_len */
1135 if (hdr->caplen < offset)
1136 return;
1137 uhdr->urb_len = SWAPLONG(uhdr->urb_len);
1138
1139 offset += 4; /* skip past data_len */
1140 if (hdr->caplen < offset)
1141 return;
1142 uhdr->data_len = SWAPLONG(uhdr->data_len);
1143
1144 if (uhdr->transfer_type == URB_ISOCHRONOUS) {
1145 offset += 4; /* skip past s.iso.error_count */
1146 if (hdr->caplen < offset)
1147 return;
1148 uhdr->s.iso.error_count = SWAPLONG(uhdr->s.iso.error_count);
1149
1150 offset += 4; /* skip past s.iso.numdesc */
1151 if (hdr->caplen < offset)
1152 return;
1153 uhdr->s.iso.numdesc = SWAPLONG(uhdr->s.iso.numdesc);
1154 } else
1155 offset += 8; /* skip USB setup header */
1156
1157 if (header_len_64_bytes) {
1158 /*
1159 * This is either the "version 1" header, with
1160 * 16 bytes of additional fields at the end, or
1161 * a "version 0" header from a memory-mapped
1162 * capture, with 16 bytes of zeroed-out padding
1163 * at the end. Byte swap them as if this were
1164 * a "version 1" header.
1165 */
1166 offset += 4; /* skip past interval */
1167 if (hdr->caplen < offset)
1168 return;
1169 uhdr->interval = SWAPLONG(uhdr->interval);
1170
1171 offset += 4; /* skip past start_frame */
1172 if (hdr->caplen < offset)
1173 return;
1174 uhdr->start_frame = SWAPLONG(uhdr->start_frame);
1175
1176 offset += 4; /* skip past xfer_flags */
1177 if (hdr->caplen < offset)
1178 return;
1179 uhdr->xfer_flags = SWAPLONG(uhdr->xfer_flags);
1180
1181 offset += 4; /* skip past ndesc */
1182 if (hdr->caplen < offset)
1183 return;
1184 uhdr->ndesc = SWAPLONG(uhdr->ndesc);
1185 }
1186
1187 if (uhdr->transfer_type == URB_ISOCHRONOUS) {
1188 /* swap the values in struct linux_usb_isodesc */
1189 pisodesc = (usb_isodesc *)(void *)(buf+offset);
1190 numdesc = uhdr->s.iso.numdesc;
1191 for (i = 0; i < numdesc; i++) {
1192 offset += 4; /* skip past status */
1193 if (hdr->caplen < offset)
1194 return;
1195 pisodesc->status = SWAPLONG(pisodesc->status);
1196
1197 offset += 4; /* skip past offset */
1198 if (hdr->caplen < offset)
1199 return;
1200 pisodesc->offset = SWAPLONG(pisodesc->offset);
1201
1202 offset += 4; /* skip past len */
1203 if (hdr->caplen < offset)
1204 return;
1205 pisodesc->len = SWAPLONG(pisodesc->len);
1206
1207 offset += 4; /* skip past padding */
1208
1209 pisodesc++;
1210 }
1211 }
1212 }