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 pcapng files
22 */
23
24 #ifdef HAVE_CONFIG_H
25 #include <config.h>
26 #endif
27
28 #include <pcap-types.h>
29
30 #include "pcap-int.h"
31 #include "extract.h"
32 #include "pcap/sll.h"
33 #include "pcap/usb.h"
34 #include "pcap/nflog.h"
35 #include "pcap/can_socketcan.h"
36
37 #include "pcap-common.h"
38
39 /*
40 * We don't write DLT_* values to capture files, because they're not the
41 * same on all platforms.
42 *
43 * Unfortunately, the various flavors of BSD have not always used the same
44 * numerical values for the same data types, and various patches to
45 * libpcap for non-BSD OSes have added their own DLT_* codes for link
46 * layer encapsulation types seen on those OSes, and those codes have had,
47 * in some cases, values that were also used, on other platforms, for other
48 * link layer encapsulation types.
49 *
50 * This means that capture files of a type whose numerical DLT_* code
51 * means different things on different BSDs, or with different versions
52 * of libpcap, can't always be read on systems other than those like
53 * the one running on the machine on which the capture was made.
54 *
55 * Instead, we define here a set of LINKTYPE_* codes, and map DLT_* codes
56 * to LINKTYPE_* codes when writing a savefile header, and map LINKTYPE_*
57 * codes to DLT_* codes when reading a savefile header.
58 *
59 * For those DLT_* codes that have, as far as we know, the same values on
60 * all platforms (DLT_NULL through DLT_FDDI), we define LINKTYPE_xxx as
61 * DLT_xxx; that way, captures of those types can still be read by
62 * versions of libpcap that map LINKTYPE_* values to DLT_* values, and
63 * captures of those types written by versions of libpcap that map DLT_
64 * values to LINKTYPE_ values can still be read by older versions
65 * of libpcap.
66 *
67 * The other LINKTYPE_* codes are given values starting at 100, in the
68 * hopes that no DLT_* code will be given one of those values.
69 *
70 * In order to ensure that a given LINKTYPE_* code's value will refer to
71 * the same encapsulation type on all platforms, you should not allocate
72 * a new LINKTYPE_* value without consulting
73 * "tcpdump-workers@lists.tcpdump.org". The tcpdump developers will
74 * allocate a value for you, and will not subsequently allocate it to
75 * anybody else; that value will be added to the "pcap.h" in the
76 * tcpdump.org Git repository, so that a future libpcap release will
77 * include it.
78 *
79 * You should, if possible, also contribute patches to libpcap and tcpdump
80 * to handle the new encapsulation type, so that they can also be checked
81 * into the tcpdump.org Git repository and so that they will appear in
82 * future libpcap and tcpdump releases.
83 *
84 * Do *NOT* assume that any values after the largest value in this file
85 * are available; you might not have the most up-to-date version of this
86 * file, and new values after that one might have been assigned. Also,
87 * do *NOT* use any values below 100 - those might already have been
88 * taken by one (or more!) organizations.
89 *
90 * Any platform that defines additional DLT_* codes should:
91 *
92 * request a LINKTYPE_* code and value from tcpdump.org,
93 * as per the above;
94 *
95 * add, in their version of libpcap, an entry to map
96 * those DLT_* codes to the corresponding LINKTYPE_*
97 * code;
98 *
99 * redefine, in their "net/bpf.h", any DLT_* values
100 * that collide with the values used by their additional
101 * DLT_* codes, to remove those collisions (but without
102 * making them collide with any of the LINKTYPE_*
103 * values equal to 50 or above; they should also avoid
104 * defining DLT_* values that collide with those
105 * LINKTYPE_* values, either).
106 */
107 #define LINKTYPE_NULL DLT_NULL
108 #define LINKTYPE_ETHERNET DLT_EN10MB /* also for 100Mb and up */
109 #define LINKTYPE_EXP_ETHERNET DLT_EN3MB /* 3Mb experimental Ethernet */
110 #define LINKTYPE_AX25 DLT_AX25
111 #define LINKTYPE_PRONET DLT_PRONET
112 #define LINKTYPE_CHAOS DLT_CHAOS
113 #define LINKTYPE_IEEE802_5 DLT_IEEE802 /* DLT_IEEE802 is used for 802.5 Token Ring */
114 #define LINKTYPE_ARCNET_BSD DLT_ARCNET /* BSD-style headers */
115 #define LINKTYPE_SLIP DLT_SLIP
116 #define LINKTYPE_PPP DLT_PPP
117 #define LINKTYPE_FDDI DLT_FDDI
118
119 /*
120 * LINKTYPE_PPP is for use when there might, or might not, be an RFC 1662
121 * PPP in HDLC-like framing header (with 0xff 0x03 before the PPP protocol
122 * field) at the beginning of the packet.
123 *
124 * This is for use when there is always such a header; the address field
125 * might be 0xff, for regular PPP, or it might be an address field for Cisco
126 * point-to-point with HDLC framing as per section 4.3.1 of RFC 1547 ("Cisco
127 * HDLC"). This is, for example, what you get with NetBSD's DLT_PPP_SERIAL.
128 *
129 * We give it the same value as NetBSD's DLT_PPP_SERIAL, in the hopes that
130 * nobody else will choose a DLT_ value of 50, and so that DLT_PPP_SERIAL
131 * captures will be written out with a link type that NetBSD's tcpdump
132 * can read.
133 */
134 #define LINKTYPE_PPP_HDLC 50 /* PPP in HDLC-like framing */
135
136 #define LINKTYPE_PPP_ETHER 51 /* NetBSD PPP-over-Ethernet */
137
138 #define LINKTYPE_SYMANTEC_FIREWALL 99 /* Symantec Enterprise Firewall */
139
140 /*
141 * These correspond to DLT_s that have different values on different
142 * platforms; we map between these values in capture files and
143 * the DLT_ values as returned by pcap_datalink() and passed to
144 * pcap_open_dead().
145 */
146 #define LINKTYPE_ATM_RFC1483 100 /* LLC/SNAP-encapsulated ATM */
147 #define LINKTYPE_RAW 101 /* raw IP */
148 #define LINKTYPE_SLIP_BSDOS 102 /* BSD/OS SLIP BPF header */
149 #define LINKTYPE_PPP_BSDOS 103 /* BSD/OS PPP BPF header */
150
151 /*
152 * Values starting with 104 are used for newly-assigned link-layer
153 * header type values; for those link-layer header types, the DLT_
154 * value returned by pcap_datalink() and passed to pcap_open_dead(),
155 * and the LINKTYPE_ value that appears in capture files, are the
156 * same.
157 *
158 * LINKTYPE_MATCHING_MIN is the lowest such value; LINKTYPE_MATCHING_MAX
159 * is the highest such value.
160 */
161 #define LINKTYPE_MATCHING_MIN 104 /* lowest value in the "matching" range */
162
163 #define LINKTYPE_C_HDLC 104 /* Cisco HDLC */
164 #define LINKTYPE_IEEE802_11 105 /* IEEE 802.11 (wireless) */
165 #define LINKTYPE_ATM_CLIP 106 /* Linux Classical IP over ATM */
166 #define LINKTYPE_FRELAY 107 /* Frame Relay */
167 #define LINKTYPE_LOOP 108 /* OpenBSD loopback */
168 #define LINKTYPE_ENC 109 /* OpenBSD IPSEC enc */
169
170 /*
171 * These three types are reserved for future use.
172 */
173 #define LINKTYPE_LANE8023 110 /* ATM LANE + 802.3 */
174 #define LINKTYPE_HIPPI 111 /* NetBSD HIPPI */
175 #define LINKTYPE_HDLC 112 /* NetBSD HDLC framing */
176
177 #define LINKTYPE_LINUX_SLL 113 /* Linux cooked socket capture */
178 #define LINKTYPE_LTALK 114 /* Apple LocalTalk hardware */
179 #define LINKTYPE_ECONET 115 /* Acorn Econet */
180
181 /*
182 * Reserved for use with OpenBSD ipfilter.
183 */
184 #define LINKTYPE_IPFILTER 116
185
186 #define LINKTYPE_PFLOG 117 /* OpenBSD DLT_PFLOG */
187 #define LINKTYPE_CISCO_IOS 118 /* For Cisco-internal use */
188 #define LINKTYPE_IEEE802_11_PRISM 119 /* 802.11 plus Prism II monitor mode radio metadata header */
189 #define LINKTYPE_IEEE802_11_AIRONET 120 /* 802.11 plus FreeBSD Aironet driver radio metadata header */
190
191 /*
192 * Reserved for Siemens HiPath HDLC.
193 */
194 #define LINKTYPE_HHDLC 121
195
196 #define LINKTYPE_IP_OVER_FC 122 /* RFC 2625 IP-over-Fibre Channel */
197 #define LINKTYPE_SUNATM 123 /* Solaris+SunATM */
198
199 /*
200 * Reserved as per request from Kent Dahlgren <kent@praesum.com>
201 * for private use.
202 */
203 #define LINKTYPE_RIO 124 /* RapidIO */
204 #define LINKTYPE_PCI_EXP 125 /* PCI Express */
205 #define LINKTYPE_AURORA 126 /* Xilinx Aurora link layer */
206
207 #define LINKTYPE_IEEE802_11_RADIOTAP 127 /* 802.11 plus radiotap radio metadata header */
208
209 /*
210 * Reserved for the TZSP encapsulation, as per request from
211 * Chris Waters <chris.waters@networkchemistry.com>
212 * TZSP is a generic encapsulation for any other link type,
213 * which includes a means to include meta-information
214 * with the packet, e.g. signal strength and channel
215 * for 802.11 packets.
216 */
217 #define LINKTYPE_TZSP 128 /* Tazmen Sniffer Protocol */
218
219 #define LINKTYPE_ARCNET_LINUX 129 /* Linux-style headers */
220
221 /*
222 * Juniper-private data link types, as per request from
223 * Hannes Gredler <hannes@juniper.net>. The corresponding
224 * DLT_s are used for passing on chassis-internal
225 * metainformation such as QOS profiles, etc..
226 */
227 #define LINKTYPE_JUNIPER_MLPPP 130
228 #define LINKTYPE_JUNIPER_MLFR 131
229 #define LINKTYPE_JUNIPER_ES 132
230 #define LINKTYPE_JUNIPER_GGSN 133
231 #define LINKTYPE_JUNIPER_MFR 134
232 #define LINKTYPE_JUNIPER_ATM2 135
233 #define LINKTYPE_JUNIPER_SERVICES 136
234 #define LINKTYPE_JUNIPER_ATM1 137
235
236 #define LINKTYPE_APPLE_IP_OVER_IEEE1394 138 /* Apple IP-over-IEEE 1394 cooked header */
237
238 #define LINKTYPE_MTP2_WITH_PHDR 139
239 #define LINKTYPE_MTP2 140
240 #define LINKTYPE_MTP3 141
241 #define LINKTYPE_SCCP 142
242
243 #define LINKTYPE_DOCSIS 143 /* DOCSIS MAC frames */
244
245 #define LINKTYPE_LINUX_IRDA 144 /* Linux-IrDA */
246
247 /*
248 * Reserved for IBM SP switch and IBM Next Federation switch.
249 */
250 #define LINKTYPE_IBM_SP 145
251 #define LINKTYPE_IBM_SN 146
252
253 /*
254 * Reserved for private use. If you have some link-layer header type
255 * that you want to use within your organization, with the capture files
256 * using that link-layer header type not ever be sent outside your
257 * organization, you can use these values.
258 *
259 * No libpcap release will use these for any purpose, nor will any
260 * tcpdump release use them, either.
261 *
262 * Do *NOT* use these in capture files that you expect anybody not using
263 * your private versions of capture-file-reading tools to read; in
264 * particular, do *NOT* use them in products, otherwise you may find that
265 * people won't be able to use tcpdump, or snort, or Ethereal, or... to
266 * read capture files from your firewall/intrusion detection/traffic
267 * monitoring/etc. appliance, or whatever product uses that LINKTYPE_ value,
268 * and you may also find that the developers of those applications will
269 * not accept patches to let them read those files.
270 *
271 * Also, do not use them if somebody might send you a capture using them
272 * for *their* private type and tools using them for *your* private type
273 * would have to read them.
274 *
275 * Instead, in those cases, ask "tcpdump-workers@lists.tcpdump.org" for a
276 * new DLT_ and LINKTYPE_ value, as per the comment in pcap/bpf.h, and use
277 * the type you're given.
278 */
279 #define LINKTYPE_USER0 147
280 #define LINKTYPE_USER1 148
281 #define LINKTYPE_USER2 149
282 #define LINKTYPE_USER3 150
283 #define LINKTYPE_USER4 151
284 #define LINKTYPE_USER5 152
285 #define LINKTYPE_USER6 153
286 #define LINKTYPE_USER7 154
287 #define LINKTYPE_USER8 155
288 #define LINKTYPE_USER9 156
289 #define LINKTYPE_USER10 157
290 #define LINKTYPE_USER11 158
291 #define LINKTYPE_USER12 159
292 #define LINKTYPE_USER13 160
293 #define LINKTYPE_USER14 161
294 #define LINKTYPE_USER15 162
295
296 /*
297 * For future use with 802.11 captures - defined by AbsoluteValue
298 * Systems to store a number of bits of link-layer information
299 * including radio information:
300 *
301 * http://www.shaftnet.org/~pizza/software/capturefrm.txt
302 */
303 #define LINKTYPE_IEEE802_11_AVS 163 /* 802.11 plus AVS radio metadata header */
304
305 /*
306 * Juniper-private data link type, as per request from
307 * Hannes Gredler <hannes@juniper.net>. The corresponding
308 * DLT_s are used for passing on chassis-internal
309 * metainformation such as QOS profiles, etc..
310 */
311 #define LINKTYPE_JUNIPER_MONITOR 164
312
313 /*
314 * BACnet MS/TP frames.
315 */
316 #define LINKTYPE_BACNET_MS_TP 165
317
318 /*
319 * Another PPP variant as per request from Karsten Keil <kkeil@suse.de>.
320 *
321 * This is used in some OSes to allow a kernel socket filter to distinguish
322 * between incoming and outgoing packets, on a socket intended to
323 * supply pppd with outgoing packets so it can do dial-on-demand and
324 * hangup-on-lack-of-demand; incoming packets are filtered out so they
325 * don't cause pppd to hold the connection up (you don't want random
326 * input packets such as port scans, packets from old lost connections,
327 * etc. to force the connection to stay up).
328 *
329 * The first byte of the PPP header (0xff03) is modified to accomodate
330 * the direction - 0x00 = IN, 0x01 = OUT.
331 */
332 #define LINKTYPE_PPP_PPPD 166
333
334 /*
335 * Juniper-private data link type, as per request from
336 * Hannes Gredler <hannes@juniper.net>. The DLT_s are used
337 * for passing on chassis-internal metainformation such as
338 * QOS profiles, cookies, etc..
339 */
340 #define LINKTYPE_JUNIPER_PPPOE 167
341 #define LINKTYPE_JUNIPER_PPPOE_ATM 168
342
343 #define LINKTYPE_GPRS_LLC 169 /* GPRS LLC */
344 #define LINKTYPE_GPF_T 170 /* GPF-T (ITU-T G.7041/Y.1303) */
345 #define LINKTYPE_GPF_F 171 /* GPF-F (ITU-T G.7041/Y.1303) */
346
347 /*
348 * Requested by Oolan Zimmer <oz@gcom.com> for use in Gcom's T1/E1 line
349 * monitoring equipment.
350 */
351 #define LINKTYPE_GCOM_T1E1 172
352 #define LINKTYPE_GCOM_SERIAL 173
353
354 /*
355 * Juniper-private data link type, as per request from
356 * Hannes Gredler <hannes@juniper.net>. The DLT_ is used
357 * for internal communication to Physical Interface Cards (PIC)
358 */
359 #define LINKTYPE_JUNIPER_PIC_PEER 174
360
361 /*
362 * Link types requested by Gregor Maier <gregor@endace.com> of Endace
363 * Measurement Systems. They add an ERF header (see
364 * http://www.endace.com/support/EndaceRecordFormat.pdf) in front of
365 * the link-layer header.
366 */
367 #define LINKTYPE_ERF_ETH 175 /* Ethernet */
368 #define LINKTYPE_ERF_POS 176 /* Packet-over-SONET */
369
370 /*
371 * Requested by Daniele Orlandi <daniele@orlandi.com> for raw LAPD
372 * for vISDN (http://www.orlandi.com/visdn/). Its link-layer header
373 * includes additional information before the LAPD header, so it's
374 * not necessarily a generic LAPD header.
375 */
376 #define LINKTYPE_LINUX_LAPD 177
377
378 /*
379 * Juniper-private data link type, as per request from
380 * Hannes Gredler <hannes@juniper.net>.
381 * The Link Types are used for prepending meta-information
382 * like interface index, interface name
383 * before standard Ethernet, PPP, Frelay & C-HDLC Frames
384 */
385 #define LINKTYPE_JUNIPER_ETHER 178
386 #define LINKTYPE_JUNIPER_PPP 179
387 #define LINKTYPE_JUNIPER_FRELAY 180
388 #define LINKTYPE_JUNIPER_CHDLC 181
389
390 /*
391 * Multi Link Frame Relay (FRF.16)
392 */
393 #define LINKTYPE_MFR 182
394
395 /*
396 * Juniper-private data link type, as per request from
397 * Hannes Gredler <hannes@juniper.net>.
398 * The DLT_ is used for internal communication with a
399 * voice Adapter Card (PIC)
400 */
401 #define LINKTYPE_JUNIPER_VP 183
402
403 /*
404 * Arinc 429 frames.
405 * DLT_ requested by Gianluca Varenni <gianluca.varenni@cacetech.com>.
406 * Every frame contains a 32bit A429 label.
407 * More documentation on Arinc 429 can be found at
408 * http://www.condoreng.com/support/downloads/tutorials/ARINCTutorial.pdf
409 */
410 #define LINKTYPE_A429 184
411
412 /*
413 * Arinc 653 Interpartition Communication messages.
414 * DLT_ requested by Gianluca Varenni <gianluca.varenni@cacetech.com>.
415 * Please refer to the A653-1 standard for more information.
416 */
417 #define LINKTYPE_A653_ICM 185
418
419 /*
420 * This used to be "USB packets, beginning with a USB setup header;
421 * requested by Paolo Abeni <paolo.abeni@email.it>."
422 *
423 * However, that header didn't work all that well - it left out some
424 * useful information - and was abandoned in favor of the DLT_USB_LINUX
425 * header.
426 *
427 * This is now used by FreeBSD for its BPF taps for USB; that has its
428 * own headers. So it is written, so it is done.
429 */
430 #define LINKTYPE_USB_FREEBSD 186
431
432 /*
433 * Bluetooth HCI UART transport layer (part H:4); requested by
434 * Paolo Abeni.
435 */
436 #define LINKTYPE_BLUETOOTH_HCI_H4 187
437
438 /*
439 * IEEE 802.16 MAC Common Part Sublayer; requested by Maria Cruz
440 * <cruz_petagay@bah.com>.
441 */
442 #define LINKTYPE_IEEE802_16_MAC_CPS 188
443
444 /*
445 * USB packets, beginning with a Linux USB header; requested by
446 * Paolo Abeni <paolo.abeni@email.it>.
447 */
448 #define LINKTYPE_USB_LINUX 189
449
450 /*
451 * Controller Area Network (CAN) v. 2.0B packets.
452 * DLT_ requested by Gianluca Varenni <gianluca.varenni@cacetech.com>.
453 * Used to dump CAN packets coming from a CAN Vector board.
454 * More documentation on the CAN v2.0B frames can be found at
455 * http://www.can-cia.org/downloads/?269
456 */
457 #define LINKTYPE_CAN20B 190
458
459 /*
460 * IEEE 802.15.4, with address fields padded, as is done by Linux
461 * drivers; requested by Juergen Schimmer.
462 */
463 #define LINKTYPE_IEEE802_15_4_LINUX 191
464
465 /*
466 * Per Packet Information encapsulated packets.
467 * LINKTYPE_ requested by Gianluca Varenni <gianluca.varenni@cacetech.com>.
468 */
469 #define LINKTYPE_PPI 192
470
471 /*
472 * Header for 802.16 MAC Common Part Sublayer plus a radiotap radio header;
473 * requested by Charles Clancy.
474 */
475 #define LINKTYPE_IEEE802_16_MAC_CPS_RADIO 193
476
477 /*
478 * Juniper-private data link type, as per request from
479 * Hannes Gredler <hannes@juniper.net>.
480 * The DLT_ is used for internal communication with a
481 * integrated service module (ISM).
482 */
483 #define LINKTYPE_JUNIPER_ISM 194
484
485 /*
486 * IEEE 802.15.4, exactly as it appears in the spec (no padding, no
487 * nothing), and with the FCS at the end of the frame; requested by
488 * Mikko Saarnivala <mikko.saarnivala@sensinode.com>.
489 *
490 * This should only be used if the FCS is present at the end of the
491 * frame; if the frame has no FCS, DLT_IEEE802_15_4_NOFCS should be
492 * used.
493 */
494 #define LINKTYPE_IEEE802_15_4_WITHFCS 195
495
496 /*
497 * Various link-layer types, with a pseudo-header, for SITA
498 * (http://www.sita.aero/); requested by Fulko Hew (fulko.hew@gmail.com).
499 */
500 #define LINKTYPE_SITA 196
501
502 /*
503 * Various link-layer types, with a pseudo-header, for Endace DAG cards;
504 * encapsulates Endace ERF records. Requested by Stephen Donnelly
505 * <stephen@endace.com>.
506 */
507 #define LINKTYPE_ERF 197
508
509 /*
510 * Special header prepended to Ethernet packets when capturing from a
511 * u10 Networks board. Requested by Phil Mulholland
512 * <phil@u10networks.com>.
513 */
514 #define LINKTYPE_RAIF1 198
515
516 /*
517 * IPMB packet for IPMI, beginning with the I2C slave address, followed
518 * by the netFn and LUN, etc.. Requested by Chanthy Toeung
519 * <chanthy.toeung@ca.kontron.com>.
520 */
521 #define LINKTYPE_IPMB 199
522
523 /*
524 * Juniper-private data link type, as per request from
525 * Hannes Gredler <hannes@juniper.net>.
526 * The DLT_ is used for capturing data on a secure tunnel interface.
527 */
528 #define LINKTYPE_JUNIPER_ST 200
529
530 /*
531 * Bluetooth HCI UART transport layer (part H:4), with pseudo-header
532 * that includes direction information; requested by Paolo Abeni.
533 */
534 #define LINKTYPE_BLUETOOTH_HCI_H4_WITH_PHDR 201
535
536 /*
537 * AX.25 packet with a 1-byte KISS header; see
538 *
539 * http://www.ax25.net/kiss.htm
540 *
541 * as per Richard Stearn <richard@rns-stearn.demon.co.uk>.
542 */
543 #define LINKTYPE_AX25_KISS 202
544
545 /*
546 * LAPD packets from an ISDN channel, starting with the address field,
547 * with no pseudo-header.
548 * Requested by Varuna De Silva <varunax@gmail.com>.
549 */
550 #define LINKTYPE_LAPD 203
551
552 /*
553 * Variants of various link-layer headers, with a one-byte direction
554 * pseudo-header prepended - zero means "received by this host",
555 * non-zero (any non-zero value) means "sent by this host" - as per
556 * Will Barker <w.barker@zen.co.uk>.
557 */
558 #define LINKTYPE_PPP_WITH_DIR 204 /* PPP */
559 #define LINKTYPE_C_HDLC_WITH_DIR 205 /* Cisco HDLC */
560 #define LINKTYPE_FRELAY_WITH_DIR 206 /* Frame Relay */
561 #define LINKTYPE_LAPB_WITH_DIR 207 /* LAPB */
562
563 /*
564 * 208 is reserved for an as-yet-unspecified proprietary link-layer
565 * type, as requested by Will Barker.
566 */
567
568 /*
569 * IPMB with a Linux-specific pseudo-header; as requested by Alexey Neyman
570 * <avn@pigeonpoint.com>.
571 */
572 #define LINKTYPE_IPMB_LINUX 209
573
574 /*
575 * FlexRay automotive bus - http://www.flexray.com/ - as requested
576 * by Hannes Kaelber <hannes.kaelber@x2e.de>.
577 */
578 #define LINKTYPE_FLEXRAY 210
579
580 /*
581 * Media Oriented Systems Transport (MOST) bus for multimedia
582 * transport - http://www.mostcooperation.com/ - as requested
583 * by Hannes Kaelber <hannes.kaelber@x2e.de>.
584 */
585 #define LINKTYPE_MOST 211
586
587 /*
588 * Local Interconnect Network (LIN) bus for vehicle networks -
589 * http://www.lin-subbus.org/ - as requested by Hannes Kaelber
590 * <hannes.kaelber@x2e.de>.
591 */
592 #define LINKTYPE_LIN 212
593
594 /*
595 * X2E-private data link type used for serial line capture,
596 * as requested by Hannes Kaelber <hannes.kaelber@x2e.de>.
597 */
598 #define LINKTYPE_X2E_SERIAL 213
599
600 /*
601 * X2E-private data link type used for the Xoraya data logger
602 * family, as requested by Hannes Kaelber <hannes.kaelber@x2e.de>.
603 */
604 #define LINKTYPE_X2E_XORAYA 214
605
606 /*
607 * IEEE 802.15.4, exactly as it appears in the spec (no padding, no
608 * nothing), but with the PHY-level data for non-ASK PHYs (4 octets
609 * of 0 as preamble, one octet of SFD, one octet of frame length+
610 * reserved bit, and then the MAC-layer data, starting with the
611 * frame control field).
612 *
613 * Requested by Max Filippov <jcmvbkbc@gmail.com>.
614 */
615 #define LINKTYPE_IEEE802_15_4_NONASK_PHY 215
616
617 /*
618 * David Gibson <david@gibson.dropbear.id.au> requested this for
619 * captures from the Linux kernel /dev/input/eventN devices. This
620 * is used to communicate keystrokes and mouse movements from the
621 * Linux kernel to display systems, such as Xorg.
622 */
623 #define LINKTYPE_LINUX_EVDEV 216
624
625 /*
626 * GSM Um and Abis interfaces, preceded by a "gsmtap" header.
627 *
628 * Requested by Harald Welte <laforge@gnumonks.org>.
629 */
630 #define LINKTYPE_GSMTAP_UM 217
631 #define LINKTYPE_GSMTAP_ABIS 218
632
633 /*
634 * MPLS, with an MPLS label as the link-layer header.
635 * Requested by Michele Marchetto <michele@openbsd.org> on behalf
636 * of OpenBSD.
637 */
638 #define LINKTYPE_MPLS 219
639
640 /*
641 * USB packets, beginning with a Linux USB header, with the USB header
642 * padded to 64 bytes; required for memory-mapped access.
643 */
644 #define LINKTYPE_USB_LINUX_MMAPPED 220
645
646 /*
647 * DECT packets, with a pseudo-header; requested by
648 * Matthias Wenzel <tcpdump@mazzoo.de>.
649 */
650 #define LINKTYPE_DECT 221
651
652 /*
653 * From: "Lidwa, Eric (GSFC-582.0)[SGT INC]" <eric.lidwa-1@nasa.gov>
654 * Date: Mon, 11 May 2009 11:18:30 -0500
655 *
656 * DLT_AOS. We need it for AOS Space Data Link Protocol.
657 * I have already written dissectors for but need an OK from
658 * legal before I can submit a patch.
659 *
660 */
661 #define LINKTYPE_AOS 222
662
663 /*
664 * Wireless HART (Highway Addressable Remote Transducer)
665 * From the HART Communication Foundation
666 * IES/PAS 62591
667 *
668 * Requested by Sam Roberts <vieuxtech@gmail.com>.
669 */
670 #define LINKTYPE_WIHART 223
671
672 /*
673 * Fibre Channel FC-2 frames, beginning with a Frame_Header.
674 * Requested by Kahou Lei <kahou82@gmail.com>.
675 */
676 #define LINKTYPE_FC_2 224
677
678 /*
679 * Fibre Channel FC-2 frames, beginning with an encoding of the
680 * SOF, and ending with an encoding of the EOF.
681 *
682 * The encodings represent the frame delimiters as 4-byte sequences
683 * representing the corresponding ordered sets, with K28.5
684 * represented as 0xBC, and the D symbols as the corresponding
685 * byte values; for example, SOFi2, which is K28.5 - D21.5 - D1.2 - D21.2,
686 * is represented as 0xBC 0xB5 0x55 0x55.
687 *
688 * Requested by Kahou Lei <kahou82@gmail.com>.
689 */
690 #define LINKTYPE_FC_2_WITH_FRAME_DELIMS 225
691
692 /*
693 * Solaris ipnet pseudo-header; requested by Darren Reed <Darren.Reed@Sun.COM>.
694 *
695 * The pseudo-header starts with a one-byte version number; for version 2,
696 * the pseudo-header is:
697 *
698 * struct dl_ipnetinfo {
699 * uint8_t dli_version;
700 * uint8_t dli_family;
701 * uint16_t dli_htype;
702 * uint32_t dli_pktlen;
703 * uint32_t dli_ifindex;
704 * uint32_t dli_grifindex;
705 * uint32_t dli_zsrc;
706 * uint32_t dli_zdst;
707 * };
708 *
709 * dli_version is 2 for the current version of the pseudo-header.
710 *
711 * dli_family is a Solaris address family value, so it's 2 for IPv4
712 * and 26 for IPv6.
713 *
714 * dli_htype is a "hook type" - 0 for incoming packets, 1 for outgoing
715 * packets, and 2 for packets arriving from another zone on the same
716 * machine.
717 *
718 * dli_pktlen is the length of the packet data following the pseudo-header
719 * (so the captured length minus dli_pktlen is the length of the
720 * pseudo-header, assuming the entire pseudo-header was captured).
721 *
722 * dli_ifindex is the interface index of the interface on which the
723 * packet arrived.
724 *
725 * dli_grifindex is the group interface index number (for IPMP interfaces).
726 *
727 * dli_zsrc is the zone identifier for the source of the packet.
728 *
729 * dli_zdst is the zone identifier for the destination of the packet.
730 *
731 * A zone number of 0 is the global zone; a zone number of 0xffffffff
732 * means that the packet arrived from another host on the network, not
733 * from another zone on the same machine.
734 *
735 * An IPv4 or IPv6 datagram follows the pseudo-header; dli_family indicates
736 * which of those it is.
737 */
738 #define LINKTYPE_IPNET 226
739
740 /*
741 * CAN (Controller Area Network) frames, with a pseudo-header as supplied
742 * by Linux SocketCAN, and with multi-byte numerical fields in that header
743 * in big-endian byte order.
744 *
745 * See Documentation/networking/can.txt in the Linux source.
746 *
747 * Requested by Felix Obenhuber <felix@obenhuber.de>.
748 */
749 #define LINKTYPE_CAN_SOCKETCAN 227
750
751 /*
752 * Raw IPv4/IPv6; different from DLT_RAW in that the DLT_ value specifies
753 * whether it's v4 or v6. Requested by Darren Reed <Darren.Reed@Sun.COM>.
754 */
755 #define LINKTYPE_IPV4 228
756 #define LINKTYPE_IPV6 229
757
758 /*
759 * IEEE 802.15.4, exactly as it appears in the spec (no padding, no
760 * nothing), and with no FCS at the end of the frame; requested by
761 * Jon Smirl <jonsmirl@gmail.com>.
762 */
763 #define LINKTYPE_IEEE802_15_4_NOFCS 230
764
765 /*
766 * Raw D-Bus:
767 *
768 * http://www.freedesktop.org/wiki/Software/dbus
769 *
770 * messages:
771 *
772 * http://dbus.freedesktop.org/doc/dbus-specification.html#message-protocol-messages
773 *
774 * starting with the endianness flag, followed by the message type, etc.,
775 * but without the authentication handshake before the message sequence:
776 *
777 * http://dbus.freedesktop.org/doc/dbus-specification.html#auth-protocol
778 *
779 * Requested by Martin Vidner <martin@vidner.net>.
780 */
781 #define LINKTYPE_DBUS 231
782
783 /*
784 * Juniper-private data link type, as per request from
785 * Hannes Gredler <hannes@juniper.net>.
786 */
787 #define LINKTYPE_JUNIPER_VS 232
788 #define LINKTYPE_JUNIPER_SRX_E2E 233
789 #define LINKTYPE_JUNIPER_FIBRECHANNEL 234
790
791 /*
792 * DVB-CI (DVB Common Interface for communication between a PC Card
793 * module and a DVB receiver). See
794 *
795 * http://www.kaiser.cx/pcap-dvbci.html
796 *
797 * for the specification.
798 *
799 * Requested by Martin Kaiser <martin@kaiser.cx>.
800 */
801 #define LINKTYPE_DVB_CI 235
802
803 /*
804 * Variant of 3GPP TS 27.010 multiplexing protocol. Requested
805 * by Hans-Christoph Schemmel <hans-christoph.schemmel@cinterion.com>.
806 */
807 #define LINKTYPE_MUX27010 236
808
809 /*
810 * STANAG 5066 D_PDUs. Requested by M. Baris Demiray
811 * <barisdemiray@gmail.com>.
812 */
813 #define LINKTYPE_STANAG_5066_D_PDU 237
814
815 /*
816 * Juniper-private data link type, as per request from
817 * Hannes Gredler <hannes@juniper.net>.
818 */
819 #define LINKTYPE_JUNIPER_ATM_CEMIC 238
820
821 /*
822 * NetFilter LOG messages
823 * (payload of netlink NFNL_SUBSYS_ULOG/NFULNL_MSG_PACKET packets)
824 *
825 * Requested by Jakub Zawadzki <darkjames-ws@darkjames.pl>
826 */
827 #define LINKTYPE_NFLOG 239
828
829 /*
830 * Hilscher Gesellschaft fuer Systemautomation mbH link-layer type
831 * for Ethernet packets with a 4-byte pseudo-header and always
832 * with the payload including the FCS, as supplied by their
833 * netANALYZER hardware and software.
834 *
835 * Requested by Holger P. Frommer <HPfrommer@hilscher.com>
836 */
837 #define LINKTYPE_NETANALYZER 240
838
839 /*
840 * Hilscher Gesellschaft fuer Systemautomation mbH link-layer type
841 * for Ethernet packets with a 4-byte pseudo-header and FCS and
842 * 1 byte of SFD, as supplied by their netANALYZER hardware and
843 * software.
844 *
845 * Requested by Holger P. Frommer <HPfrommer@hilscher.com>
846 */
847 #define LINKTYPE_NETANALYZER_TRANSPARENT 241
848
849 /*
850 * IP-over-InfiniBand, as specified by RFC 4391.
851 *
852 * Requested by Petr Sumbera <petr.sumbera@oracle.com>.
853 */
854 #define LINKTYPE_IPOIB 242
855
856 /*
857 * MPEG-2 transport stream (ISO 13818-1/ITU-T H.222.0).
858 *
859 * Requested by Guy Martin <gmsoft@tuxicoman.be>.
860 */
861 #define LINKTYPE_MPEG_2_TS 243
862
863 /*
864 * ng4T GmbH's UMTS Iub/Iur-over-ATM and Iub/Iur-over-IP format as
865 * used by their ng40 protocol tester.
866 *
867 * Requested by Jens Grimmer <jens.grimmer@ng4t.com>.
868 */
869 #define LINKTYPE_NG40 244
870
871 /*
872 * Pseudo-header giving adapter number and flags, followed by an NFC
873 * (Near-Field Communications) Logical Link Control Protocol (LLCP) PDU,
874 * as specified by NFC Forum Logical Link Control Protocol Technical
875 * Specification LLCP 1.1.
876 *
877 * Requested by Mike Wakerly <mikey@google.com>.
878 */
879 #define LINKTYPE_NFC_LLCP 245
880
881 /*
882 * pfsync output; DLT_PFSYNC is 18, which collides with DLT_CIP in
883 * SuSE 6.3, on OpenBSD, NetBSD, DragonFly BSD, and macOS, and
884 * is 121, which collides with DLT_HHDLC, in FreeBSD. We pick a
885 * shiny new link-layer header type value that doesn't collide with
886 * anything, in the hopes that future pfsync savefiles, if any,
887 * won't require special hacks to distinguish from other savefiles.
888 *
889 */
890 #define LINKTYPE_PFSYNC 246
891
892 /*
893 * Raw InfiniBand packets, starting with the Local Routing Header.
894 *
895 * Requested by Oren Kladnitsky <orenk@mellanox.com>.
896 */
897 #define LINKTYPE_INFINIBAND 247
898
899 /*
900 * SCTP, with no lower-level protocols (i.e., no IPv4 or IPv6).
901 *
902 * Requested by Michael Tuexen <Michael.Tuexen@lurchi.franken.de>.
903 */
904 #define LINKTYPE_SCTP 248
905
906 /*
907 * USB packets, beginning with a USBPcap header.
908 *
909 * Requested by Tomasz Mon <desowin@gmail.com>
910 */
911 #define LINKTYPE_USBPCAP 249
912
913 /*
914 * Schweitzer Engineering Laboratories "RTAC" product serial-line
915 * packets.
916 *
917 * Requested by Chris Bontje <chris_bontje@selinc.com>.
918 */
919 #define DLT_RTAC_SERIAL 250
920
921 /*
922 * Bluetooth Low Energy air interface link-layer packets.
923 *
924 * Requested by Mike Kershaw <dragorn@kismetwireless.net>.
925 */
926 #define LINKTYPE_BLUETOOTH_LE_LL 251
927
928 /*
929 * Link-layer header type for upper-protocol layer PDU saves from wireshark.
930 *
931 * the actual contents are determined by two TAGs stored with each
932 * packet:
933 * EXP_PDU_TAG_LINKTYPE the link type (LINKTYPE_ value) of the
934 * original packet.
935 *
936 * EXP_PDU_TAG_PROTO_NAME the name of the wireshark dissector
937 * that can make sense of the data stored.
938 */
939 #define LINKTYPE_WIRESHARK_UPPER_PDU 252
940
941 /*
942 * Link-layer header type for the netlink protocol (nlmon devices).
943 */
944 #define LINKTYPE_NETLINK 253
945
946 /*
947 * Bluetooth Linux Monitor headers for the BlueZ stack.
948 */
949 #define LINKTYPE_BLUETOOTH_LINUX_MONITOR 254
950
951 /*
952 * Bluetooth Basic Rate/Enhanced Data Rate baseband packets, as
953 * captured by Ubertooth.
954 */
955 #define LINKTYPE_BLUETOOTH_BREDR_BB 255
956
957 /*
958 * Bluetooth Low Energy link layer packets, as captured by Ubertooth.
959 */
960 #define LINKTYPE_BLUETOOTH_LE_LL_WITH_PHDR 256
961
962 /*
963 * PROFIBUS data link layer.
964 */
965 #define LINKTYPE_PROFIBUS_DL 257
966
967 /*
968 * Apple's DLT_PKTAP headers.
969 *
970 * Sadly, the folks at Apple either had no clue that the DLT_USERn values
971 * are for internal use within an organization and partners only, and
972 * didn't know that the right way to get a link-layer header type is to
973 * ask tcpdump.org for one, or knew and didn't care, so they just
974 * used DLT_USER2, which causes problems for everything except for
975 * their version of tcpdump.
976 *
977 * So I'll just give them one; hopefully this will show up in a
978 * libpcap release in time for them to get this into 10.10 Big Sur
979 * or whatever Mavericks' successor is called. LINKTYPE_PKTAP
980 * will be 258 *even on macOS*; that is *intentional*, so that
981 * PKTAP files look the same on *all* OSes (different OSes can have
982 * different numerical values for a given DLT_, but *MUST NOT* have
983 * different values for what goes in a file, as files can be moved
984 * between OSes!).
985 */
986 #define LINKTYPE_PKTAP 258
987
988 /*
989 * Ethernet packets preceded by a header giving the last 6 octets
990 * of the preamble specified by 802.3-2012 Clause 65, section
991 * 65.1.3.2 "Transmit".
992 */
993 #define LINKTYPE_EPON 259
994
995 /*
996 * IPMI trace packets, as specified by Table 3-20 "Trace Data Block Format"
997 * in the PICMG HPM.2 specification.
998 */
999 #define LINKTYPE_IPMI_HPM_2 260
1000
1001 /*
1002 * per Joshua Wright <jwright@hasborg.com>, formats for Zwave captures.
1003 */
1004 #define LINKTYPE_ZWAVE_R1_R2 261
1005 #define LINKTYPE_ZWAVE_R3 262
1006
1007 /*
1008 * per Steve Karg <skarg@users.sourceforge.net>, formats for Wattstopper
1009 * Digital Lighting Management room bus serial protocol captures.
1010 */
1011 #define LINKTYPE_WATTSTOPPER_DLM 263
1012
1013 /*
1014 * ISO 14443 contactless smart card messages.
1015 */
1016 #define LINKTYPE_ISO_14443 264
1017
1018 /*
1019 * Radio data system (RDS) groups. IEC 62106.
1020 * Per Jonathan Brucker <jonathan.brucke@gmail.com>.
1021 */
1022 #define LINKTYPE_RDS 265
1023
1024 /*
1025 * USB packets, beginning with a Darwin (macOS, etc.) header.
1026 */
1027 #define LINKTYPE_USB_DARWIN 266
1028
1029 /*
1030 * OpenBSD DLT_OPENFLOW.
1031 */
1032 #define LINKTYPE_OPENFLOW 267
1033
1034 /*
1035 * SDLC frames containing SNA PDUs.
1036 */
1037 #define LINKTYPE_SDLC 268
1038
1039 /*
1040 * per "Selvig, Bjorn" <b.selvig@ti.com> used for
1041 * TI protocol sniffer.
1042 */
1043 #define LINKTYPE_TI_LLN_SNIFFER 269
1044
1045 /*
1046 * per: Erik de Jong <erikdejong at gmail.com> for
1047 * https://github.com/eriknl/LoRaTap/releases/tag/v0.1
1048 */
1049 #define LINKTYPE_LORATAP 270
1050
1051 /*
1052 * per: Stefanha at gmail.com for
1053 * http://lists.sandelman.ca/pipermail/tcpdump-workers/2017-May/000772.html
1054 * and: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/include/uapi/linux/vsockmon.h
1055 * for: http://qemu-project.org/Features/VirtioVsock
1056 */
1057 #define LINKTYPE_VSOCK 271
1058
1059 /*
1060 * Nordic Semiconductor Bluetooth LE sniffer.
1061 */
1062 #define LINKTYPE_NORDIC_BLE 272
1063
1064 /*
1065 * Excentis DOCSIS 3.1 RF sniffer (XRA-31)
1066 * per: bruno.verstuyft at excentis.com
1067 * http://www.xra31.com/xra-header
1068 */
1069 #define LINKTYPE_DOCSIS31_XRA31 273
1070
1071 /*
1072 * mPackets, as specified by IEEE 802.3br Figure 99-4, starting
1073 * with the preamble and always ending with a CRC field.
1074 */
1075 #define LINKTYPE_ETHERNET_MPACKET 274
1076
1077 /*
1078 * DisplayPort AUX channel monitoring data as specified by VESA
1079 * DisplayPort(DP) Standard preceeded by a pseudo-header.
1080 * per dirk.eibach at gdsys.cc
1081 */
1082 #define LINKTYPE_DISPLAYPORT_AUX 275
1083
1084 #define LINKTYPE_MATCHING_MAX 275 /* highest value in the "matching" range */
1085
1086 /*
1087 * The DLT_ and LINKTYPE_ values in the "matching" range should be the
1088 * same, so DLT_MATCHING_MAX and LINKTYPE_MATCHING_MAX should be the
1089 * same.
1090 */
1091 #if LINKTYPE_MATCHING_MAX != DLT_MATCHING_MAX
1092 #error The LINKTYPE_ matching range does not match the DLT_ matching range
1093 #endif
1094
1095 static struct linktype_map {
1096 int dlt;
1097 int linktype;
1098 } map[] = {
1099 /*
1100 * These DLT_* codes have LINKTYPE_* codes with values identical
1101 * to the values of the corresponding DLT_* code.
1102 */
1103 { DLT_NULL, LINKTYPE_NULL },
1104 { DLT_EN10MB, LINKTYPE_ETHERNET },
1105 { DLT_EN3MB, LINKTYPE_EXP_ETHERNET },
1106 { DLT_AX25, LINKTYPE_AX25 },
1107 { DLT_PRONET, LINKTYPE_PRONET },
1108 { DLT_CHAOS, LINKTYPE_CHAOS },
1109 { DLT_IEEE802, LINKTYPE_IEEE802_5 },
1110 { DLT_ARCNET, LINKTYPE_ARCNET_BSD },
1111 { DLT_SLIP, LINKTYPE_SLIP },
1112 { DLT_PPP, LINKTYPE_PPP },
1113 { DLT_FDDI, LINKTYPE_FDDI },
1114 { DLT_SYMANTEC_FIREWALL, LINKTYPE_SYMANTEC_FIREWALL },
1115
1116 /*
1117 * These DLT_* codes have different values on different
1118 * platforms; we map them to LINKTYPE_* codes that
1119 * have values that should never be equal to any DLT_*
1120 * code.
1121 */
1122 #ifdef DLT_FR
1123 /* BSD/OS Frame Relay */
1124 { DLT_FR, LINKTYPE_FRELAY },
1125 #endif
1126
1127 { DLT_ATM_RFC1483, LINKTYPE_ATM_RFC1483 },
1128 { DLT_RAW, LINKTYPE_RAW },
1129 { DLT_SLIP_BSDOS, LINKTYPE_SLIP_BSDOS },
1130 { DLT_PPP_BSDOS, LINKTYPE_PPP_BSDOS },
1131
1132 /* BSD/OS Cisco HDLC */
1133 { DLT_C_HDLC, LINKTYPE_C_HDLC },
1134
1135 /*
1136 * These DLT_* codes are not on all platforms, but, so far,
1137 * there don't appear to be any platforms that define
1138 * other codes with those values; we map them to
1139 * different LINKTYPE_* values anyway, just in case.
1140 */
1141
1142 /* Linux ATM Classical IP */
1143 { DLT_ATM_CLIP, LINKTYPE_ATM_CLIP },
1144
1145 /* NetBSD sync/async serial PPP (or Cisco HDLC) */
1146 { DLT_PPP_SERIAL, LINKTYPE_PPP_HDLC },
1147
1148 /* NetBSD PPP over Ethernet */
1149 { DLT_PPP_ETHER, LINKTYPE_PPP_ETHER },
1150
1151 /*
1152 * All LINKTYPE_ values between LINKTYPE_MATCHING_MIN
1153 * and LINKTYPE_MATCHING_MAX are mapped to identical
1154 * DLT_ values.
1155 */
1156
1157 { -1, -1 }
1158 };
1159
1160 int
dlt_to_linktype(int dlt)1161 dlt_to_linktype(int dlt)
1162 {
1163 int i;
1164
1165 /*
1166 * DLTs that, on some platforms, have values in the matching range
1167 * but that *don't* have the same value as the corresponding
1168 * LINKTYPE because, for some reason, not all OSes have the
1169 * same value for that DLT (note that the DLT's value might be
1170 * outside the matching range on some of those OSes).
1171 */
1172 if (dlt == DLT_PFSYNC)
1173 return (LINKTYPE_PFSYNC);
1174 if (dlt == DLT_PKTAP)
1175 return (LINKTYPE_PKTAP);
1176
1177 /*
1178 * For all other values in the matching range, the DLT
1179 * value is the same as the LINKTYPE value.
1180 */
1181 if (dlt >= DLT_MATCHING_MIN && dlt <= DLT_MATCHING_MAX)
1182 return (dlt);
1183
1184 /*
1185 * Map the values outside that range.
1186 */
1187 for (i = 0; map[i].dlt != -1; i++) {
1188 if (map[i].dlt == dlt)
1189 return (map[i].linktype);
1190 }
1191
1192 /*
1193 * If we don't have a mapping for this DLT, return an
1194 * error; that means that this is a value with no corresponding
1195 * LINKTYPE, and we need to assign one.
1196 */
1197 return (-1);
1198 }
1199
1200 int
linktype_to_dlt(int linktype)1201 linktype_to_dlt(int linktype)
1202 {
1203 int i;
1204
1205 /*
1206 * LINKTYPEs in the matching range that *don't*
1207 * have the same value as the corresponding DLTs
1208 * because, for some reason, not all OSes have the
1209 * same value for that DLT.
1210 */
1211 if (linktype == LINKTYPE_PFSYNC)
1212 return (DLT_PFSYNC);
1213 if (linktype == LINKTYPE_PKTAP)
1214 return (DLT_PKTAP);
1215
1216 /*
1217 * For all other values in the matching range, the LINKTYPE
1218 * value is the same as the DLT value.
1219 */
1220 if (linktype >= LINKTYPE_MATCHING_MIN &&
1221 linktype <= LINKTYPE_MATCHING_MAX)
1222 return (linktype);
1223
1224 /*
1225 * Map the values outside that range.
1226 */
1227 for (i = 0; map[i].linktype != -1; i++) {
1228 if (map[i].linktype == linktype)
1229 return (map[i].dlt);
1230 }
1231
1232 /*
1233 * If we don't have an entry for this LINKTYPE, return
1234 * the link type value; it may be a DLT from an older
1235 * version of libpcap.
1236 */
1237 return linktype;
1238 }
1239
1240 /*
1241 * Return the maximum snapshot length for a given DLT_ value.
1242 *
1243 * For most link-layer types, we use MAXIMUM_SNAPLEN, but for DLT_DBUS,
1244 * the maximum is 134217728, as per
1245 *
1246 * https://dbus.freedesktop.org/doc/dbus-specification.html#message-protocol-messages
1247 */
1248 u_int
max_snaplen_for_dlt(int dlt)1249 max_snaplen_for_dlt(int dlt)
1250 {
1251 if (dlt == DLT_DBUS)
1252 return 134217728;
1253 else
1254 return MAXIMUM_SNAPLEN;
1255 }
1256
1257 /*
1258 * DLT_LINUX_SLL packets with a protocol type of LINUX_SLL_P_CAN or
1259 * LINUX_SLL_P_CANFD have SocketCAN headers in front of the payload,
1260 * with the CAN ID being in host byte order.
1261 *
1262 * When reading a DLT_LINUX_SLL capture file, we need to check for those
1263 * packets and convert the CAN ID from the byte order of the host that
1264 * wrote the file to this host's byte order.
1265 */
1266 static void
swap_linux_sll_header(const struct pcap_pkthdr * hdr,u_char * buf)1267 swap_linux_sll_header(const struct pcap_pkthdr *hdr, u_char *buf)
1268 {
1269 u_int caplen = hdr->caplen;
1270 u_int length = hdr->len;
1271 struct sll_header *shdr = (struct sll_header *)buf;
1272 uint16_t protocol;
1273 pcap_can_socketcan_hdr *chdr;
1274
1275 if (caplen < (u_int) sizeof(struct sll_header) ||
1276 length < (u_int) sizeof(struct sll_header)) {
1277 /* Not enough data to have the protocol field */
1278 return;
1279 }
1280
1281 protocol = EXTRACT_16BITS(&shdr->sll_protocol);
1282 if (protocol != LINUX_SLL_P_CAN && protocol != LINUX_SLL_P_CANFD)
1283 return;
1284
1285 /*
1286 * SocketCAN packet; fix up the packet's header.
1287 */
1288 chdr = (pcap_can_socketcan_hdr *)(buf + sizeof(struct sll_header));
1289 if (caplen < (u_int) sizeof(struct sll_header) + sizeof(chdr->can_id) ||
1290 length < (u_int) sizeof(struct sll_header) + sizeof(chdr->can_id)) {
1291 /* Not enough data to have the CAN ID */
1292 return;
1293 }
1294 chdr->can_id = SWAPLONG(chdr->can_id);
1295 }
1296
1297 /*
1298 * The DLT_USB_LINUX and DLT_USB_LINUX_MMAPPED headers are in host
1299 * byte order when capturing (it's supplied directly from a
1300 * memory-mapped buffer shared by the kernel).
1301 *
1302 * When reading a DLT_USB_LINUX or DLT_USB_LINUX_MMAPPED capture file,
1303 * we need to convert it from the byte order of the host that wrote
1304 * the file to this host's byte order.
1305 */
1306 static void
swap_linux_usb_header(const struct pcap_pkthdr * hdr,u_char * buf,int header_len_64_bytes)1307 swap_linux_usb_header(const struct pcap_pkthdr *hdr, u_char *buf,
1308 int header_len_64_bytes)
1309 {
1310 pcap_usb_header_mmapped *uhdr = (pcap_usb_header_mmapped *)buf;
1311 bpf_u_int32 offset = 0;
1312
1313 /*
1314 * "offset" is the offset *past* the field we're swapping;
1315 * we skip the field *before* checking to make sure
1316 * the captured data length includes the entire field.
1317 */
1318
1319 /*
1320 * The URB id is a totally opaque value; do we really need to
1321 * convert it to the reading host's byte order???
1322 */
1323 offset += 8; /* skip past id */
1324 if (hdr->caplen < offset)
1325 return;
1326 uhdr->id = SWAPLL(uhdr->id);
1327
1328 offset += 4; /* skip past various 1-byte fields */
1329
1330 offset += 2; /* skip past bus_id */
1331 if (hdr->caplen < offset)
1332 return;
1333 uhdr->bus_id = SWAPSHORT(uhdr->bus_id);
1334
1335 offset += 2; /* skip past various 1-byte fields */
1336
1337 offset += 8; /* skip past ts_sec */
1338 if (hdr->caplen < offset)
1339 return;
1340 uhdr->ts_sec = SWAPLL(uhdr->ts_sec);
1341
1342 offset += 4; /* skip past ts_usec */
1343 if (hdr->caplen < offset)
1344 return;
1345 uhdr->ts_usec = SWAPLONG(uhdr->ts_usec);
1346
1347 offset += 4; /* skip past status */
1348 if (hdr->caplen < offset)
1349 return;
1350 uhdr->status = SWAPLONG(uhdr->status);
1351
1352 offset += 4; /* skip past urb_len */
1353 if (hdr->caplen < offset)
1354 return;
1355 uhdr->urb_len = SWAPLONG(uhdr->urb_len);
1356
1357 offset += 4; /* skip past data_len */
1358 if (hdr->caplen < offset)
1359 return;
1360 uhdr->data_len = SWAPLONG(uhdr->data_len);
1361
1362 if (uhdr->transfer_type == URB_ISOCHRONOUS) {
1363 offset += 4; /* skip past s.iso.error_count */
1364 if (hdr->caplen < offset)
1365 return;
1366 uhdr->s.iso.error_count = SWAPLONG(uhdr->s.iso.error_count);
1367
1368 offset += 4; /* skip past s.iso.numdesc */
1369 if (hdr->caplen < offset)
1370 return;
1371 uhdr->s.iso.numdesc = SWAPLONG(uhdr->s.iso.numdesc);
1372 } else
1373 offset += 8; /* skip USB setup header */
1374
1375 /*
1376 * With the old header, there are no isochronous descriptors
1377 * after the header.
1378 *
1379 * With the new header, the actual number of descriptors in
1380 * the header is not s.iso.numdesc, it's ndesc - only the
1381 * first N descriptors, for some value of N, are put into
1382 * the header, and ndesc is set to the actual number copied.
1383 * In addition, if s.iso.numdesc is negative, no descriptors
1384 * are captured, and ndesc is set to 0.
1385 */
1386 if (header_len_64_bytes) {
1387 /*
1388 * This is either the "version 1" header, with
1389 * 16 bytes of additional fields at the end, or
1390 * a "version 0" header from a memory-mapped
1391 * capture, with 16 bytes of zeroed-out padding
1392 * at the end. Byte swap them as if this were
1393 * a "version 1" header.
1394 */
1395 offset += 4; /* skip past interval */
1396 if (hdr->caplen < offset)
1397 return;
1398 uhdr->interval = SWAPLONG(uhdr->interval);
1399
1400 offset += 4; /* skip past start_frame */
1401 if (hdr->caplen < offset)
1402 return;
1403 uhdr->start_frame = SWAPLONG(uhdr->start_frame);
1404
1405 offset += 4; /* skip past xfer_flags */
1406 if (hdr->caplen < offset)
1407 return;
1408 uhdr->xfer_flags = SWAPLONG(uhdr->xfer_flags);
1409
1410 offset += 4; /* skip past ndesc */
1411 if (hdr->caplen < offset)
1412 return;
1413 uhdr->ndesc = SWAPLONG(uhdr->ndesc);
1414
1415 if (uhdr->transfer_type == URB_ISOCHRONOUS) {
1416 /* swap the values in struct linux_usb_isodesc */
1417 usb_isodesc *pisodesc;
1418 uint32_t i;
1419
1420 pisodesc = (usb_isodesc *)(void *)(buf+offset);
1421 for (i = 0; i < uhdr->ndesc; i++) {
1422 offset += 4; /* skip past status */
1423 if (hdr->caplen < offset)
1424 return;
1425 pisodesc->status = SWAPLONG(pisodesc->status);
1426
1427 offset += 4; /* skip past offset */
1428 if (hdr->caplen < offset)
1429 return;
1430 pisodesc->offset = SWAPLONG(pisodesc->offset);
1431
1432 offset += 4; /* skip past len */
1433 if (hdr->caplen < offset)
1434 return;
1435 pisodesc->len = SWAPLONG(pisodesc->len);
1436
1437 offset += 4; /* skip past padding */
1438
1439 pisodesc++;
1440 }
1441 }
1442 }
1443 }
1444
1445 /*
1446 * The DLT_NFLOG "packets" have a mixture of big-endian and host-byte-order
1447 * data. They begin with a fixed-length header with big-endian fields,
1448 * followed by a set of TLVs, where the type and length are in host
1449 * byte order but the values are either big-endian or are a raw byte
1450 * sequence that's the same regardless of the host's byte order.
1451 *
1452 * When reading a DLT_NFLOG capture file, we need to convert the type
1453 * and length values from the byte order of the host that wrote the
1454 * file to the byte order of this host.
1455 */
1456 static void
swap_nflog_header(const struct pcap_pkthdr * hdr,u_char * buf)1457 swap_nflog_header(const struct pcap_pkthdr *hdr, u_char *buf)
1458 {
1459 u_char *p = buf;
1460 nflog_hdr_t *nfhdr = (nflog_hdr_t *)buf;
1461 nflog_tlv_t *tlv;
1462 u_int caplen = hdr->caplen;
1463 u_int length = hdr->len;
1464 uint16_t size;
1465
1466 if (caplen < (u_int) sizeof(nflog_hdr_t) ||
1467 length < (u_int) sizeof(nflog_hdr_t)) {
1468 /* Not enough data to have any TLVs. */
1469 return;
1470 }
1471
1472 if (nfhdr->nflog_version != 0) {
1473 /* Unknown NFLOG version */
1474 return;
1475 }
1476
1477 length -= sizeof(nflog_hdr_t);
1478 caplen -= sizeof(nflog_hdr_t);
1479 p += sizeof(nflog_hdr_t);
1480
1481 while (caplen >= sizeof(nflog_tlv_t)) {
1482 tlv = (nflog_tlv_t *) p;
1483
1484 /* Swap the type and length. */
1485 tlv->tlv_type = SWAPSHORT(tlv->tlv_type);
1486 tlv->tlv_length = SWAPSHORT(tlv->tlv_length);
1487
1488 /* Get the length of the TLV. */
1489 size = tlv->tlv_length;
1490 if (size % 4 != 0)
1491 size += 4 - size % 4;
1492
1493 /* Is the TLV's length less than the minimum? */
1494 if (size < sizeof(nflog_tlv_t)) {
1495 /* Yes. Give up now. */
1496 return;
1497 }
1498
1499 /* Do we have enough data for the full TLV? */
1500 if (caplen < size || length < size) {
1501 /* No. */
1502 return;
1503 }
1504
1505 /* Skip over the TLV. */
1506 length -= size;
1507 caplen -= size;
1508 p += size;
1509 }
1510 }
1511
1512 void
swap_pseudo_headers(int linktype,struct pcap_pkthdr * hdr,u_char * data)1513 swap_pseudo_headers(int linktype, struct pcap_pkthdr *hdr, u_char *data)
1514 {
1515 /*
1516 * Convert pseudo-headers from the byte order of
1517 * the host on which the file was saved to our
1518 * byte order, as necessary.
1519 */
1520 switch (linktype) {
1521
1522 case DLT_LINUX_SLL:
1523 swap_linux_sll_header(hdr, data);
1524 break;
1525
1526 case DLT_USB_LINUX:
1527 swap_linux_usb_header(hdr, data, 0);
1528 break;
1529
1530 case DLT_USB_LINUX_MMAPPED:
1531 swap_linux_usb_header(hdr, data, 1);
1532 break;
1533
1534 case DLT_NFLOG:
1535 swap_nflog_header(hdr, data);
1536 break;
1537 }
1538 }
1539