xref: /netbsd-src/external/bsd/libpcap/dist/pcap-common.c (revision 8bda04910f1f2c366c51d4cbd40df19f5b57f1dd)
1 /*	$NetBSD: pcap-common.c,v 1.9 2024/09/02 15:33:37 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1993, 1994, 1995, 1996, 1997
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that: (1) source code distributions
9  * retain the above copyright notice and this paragraph in its entirety, (2)
10  * distributions including binary code include the above copyright notice and
11  * this paragraph in its entirety in the documentation or other materials
12  * provided with the distribution, and (3) all advertising materials mentioning
13  * features or use of this software display the following acknowledgement:
14  * ``This product includes software developed by the University of California,
15  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
16  * the University nor the names of its contributors may be used to endorse
17  * or promote products derived from this software without specific prior
18  * written permission.
19  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
20  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
21  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
22  *
23  * pcap-common.c - common code for pcap and pcapng files
24  */
25 
26 #include <sys/cdefs.h>
27 __RCSID("$NetBSD: pcap-common.c,v 1.9 2024/09/02 15:33:37 christos Exp $");
28 
29 #include <config.h>
30 
31 #include <pcap-types.h>
32 
33 #include "pcap-int.h"
34 
35 #include "pcap-common.h"
36 
37 /*
38  * We don't write DLT_* values to capture files, because they're not the
39  * same on all platforms.
40  *
41  * Unfortunately, the various flavors of BSD have not always used the same
42  * numerical values for the same data types, and various patches to
43  * libpcap for non-BSD OSes have added their own DLT_* codes for link
44  * layer encapsulation types seen on those OSes, and those codes have had,
45  * in some cases, values that were also used, on other platforms, for other
46  * link layer encapsulation types.
47  *
48  * This means that capture files of a type whose numerical DLT_* code
49  * means different things on different BSDs, or with different versions
50  * of libpcap, can't always be read on systems other than those like
51  * the one running on the machine on which the capture was made.
52  *
53  * Instead, we define here a set of LINKTYPE_* codes, and map DLT_* codes
54  * to LINKTYPE_* codes when writing a savefile header, and map LINKTYPE_*
55  * codes to DLT_* codes when reading a savefile header.
56  *
57  * For those DLT_* codes that have, as far as we know, the same values on
58  * all platforms (DLT_NULL through DLT_FDDI), we define LINKTYPE_xxx as
59  * DLT_xxx; that way, captures of those types can still be read by
60  * versions of libpcap that map LINKTYPE_* values to DLT_* values, and
61  * captures of those types written by versions of libpcap that map DLT_
62  * values to LINKTYPE_ values can still be read by older versions
63  * of libpcap.
64  *
65  * The other LINKTYPE_* codes are given values starting at 100, in the
66  * hopes that no DLT_* code will be given one of those values.
67  *
68  * In order to ensure that a given LINKTYPE_* code's value will refer to
69  * the same encapsulation type on all platforms, you should not allocate
70  * a new LINKTYPE_* value without consulting
71  * "tcpdump-workers@lists.tcpdump.org".  The tcpdump developers will
72  * allocate a value for you, and will not subsequently allocate it to
73  * anybody else; that value will be added to the "pcap.h" in the
74  * tcpdump.org Git repository, so that a future libpcap release will
75  * include it.
76  *
77  * You should, if possible, also contribute patches to libpcap and tcpdump
78  * to handle the new encapsulation type, so that they can also be checked
79  * into the tcpdump.org Git repository and so that they will appear in
80  * future libpcap and tcpdump releases.
81  *
82  * Do *NOT* assume that any values after the largest value in this file
83  * are available; you might not have the most up-to-date version of this
84  * file, and new values after that one might have been assigned.  Also,
85  * do *NOT* use any values below 100 - those might already have been
86  * taken by one (or more!) organizations.
87  *
88  * Any platform that defines additional DLT_* codes should:
89  *
90  *	request a LINKTYPE_* code and value from tcpdump.org,
91  *	as per the above;
92  *
93  *	add, in their version of libpcap, an entry to map
94  *	those DLT_* codes to the corresponding LINKTYPE_*
95  *	code;
96  *
97  *	redefine, in their "net/bpf.h", any DLT_* values
98  *	that collide with the values used by their additional
99  *	DLT_* codes, to remove those collisions (but without
100  *	making them collide with any of the LINKTYPE_*
101  *	values equal to 50 or above; they should also avoid
102  *	defining DLT_* values that collide with those
103  *	LINKTYPE_* values, either).
104  */
105 
106 /*
107  * These values the DLT_ values for which are the same on all platforms,
108  * and that have been defined by <net/bpf.h> for ages.
109  *
110  * For those, the LINKTYPE_ values are equal to the DLT_ values.
111  *
112  * LINKTYPE_LOW_MATCHING_MIN is the lowest such value;
113  * LINKTYPE_LOW_MATCHING_MAX is the highest such value.
114  */
115 #define LINKTYPE_LOW_MATCHING_MIN	0		/* lowest value in this "matching" range */
116 #define LINKTYPE_NULL		DLT_NULL
117 #define LINKTYPE_ETHERNET	DLT_EN10MB	/* also for 100Mb and up */
118 #define LINKTYPE_EXP_ETHERNET	DLT_EN3MB	/* 3Mb experimental Ethernet */
119 #define LINKTYPE_AX25		DLT_AX25
120 #define LINKTYPE_PRONET		DLT_PRONET
121 #define LINKTYPE_CHAOS		DLT_CHAOS
122 #define LINKTYPE_IEEE802_5	DLT_IEEE802	/* DLT_IEEE802 is used for 802.5 Token Ring */
123 #define LINKTYPE_ARCNET_BSD	DLT_ARCNET	/* BSD-style headers */
124 #define LINKTYPE_SLIP		DLT_SLIP
125 #define LINKTYPE_PPP		DLT_PPP
126 #define LINKTYPE_FDDI		DLT_FDDI
127 
128 #define LINKTYPE_LOW_MATCHING_MAX	LINKTYPE_FDDI	/* highest value in this "matching" range */
129 
130 /*
131  * LINKTYPE_PPP is for use when there might, or might not, be an RFC 1662
132  * PPP in HDLC-like framing header (with 0xff 0x03 before the PPP protocol
133  * field) at the beginning of the packet.
134  *
135  * This is for use when there is always such a header; the address field
136  * might be 0xff, for regular PPP, or it might be an address field for Cisco
137  * point-to-point with HDLC framing as per section 4.3.1 of RFC 1547 ("Cisco
138  * HDLC").  This is, for example, what you get with NetBSD's DLT_PPP_SERIAL.
139  *
140  * We give it the same value as NetBSD's DLT_PPP_SERIAL, in the hopes that
141  * nobody else will choose a DLT_ value of 50, and so that DLT_PPP_SERIAL
142  * captures will be written out with a link type that NetBSD's tcpdump
143  * can read.
144  */
145 #define LINKTYPE_PPP_HDLC	50		/* PPP in HDLC-like framing */
146 
147 #define LINKTYPE_PPP_ETHER	51		/* NetBSD PPP-over-Ethernet */
148 
149 #define LINKTYPE_SYMANTEC_FIREWALL 99		/* Symantec Enterprise Firewall */
150 
151 /*
152  * These correspond to DLT_s that have different values on different
153  * platforms; we map between these values in capture files and
154  * the DLT_ values as returned by pcap_datalink() and passed to
155  * pcap_open_dead().
156  */
157 #define LINKTYPE_ATM_RFC1483	100		/* LLC/SNAP-encapsulated ATM */
158 #define LINKTYPE_RAW		101		/* raw IP */
159 #define LINKTYPE_SLIP_BSDOS	102		/* BSD/OS SLIP BPF header */
160 #define LINKTYPE_PPP_BSDOS	103		/* BSD/OS PPP BPF header */
161 
162 /*
163  * Values starting with 104 are used for newly-assigned link-layer
164  * header type values; for those link-layer header types, the DLT_
165  * value returned by pcap_datalink() and passed to pcap_open_dead(),
166  * and the LINKTYPE_ value that appears in capture files, are the
167  * same.
168  *
169  * LINKTYPE_HIGH_MATCHING_MIN is the lowest such value;
170  * LINKTYPE_HIGH_MATCHING_MAX is the highest such value.
171  */
172 #define LINKTYPE_HIGH_MATCHING_MIN	104		/* lowest value in the "matching" range */
173 
174 #define LINKTYPE_C_HDLC		104		/* Cisco HDLC */
175 #define LINKTYPE_IEEE802_11	105		/* IEEE 802.11 (wireless) */
176 #define LINKTYPE_ATM_CLIP	106		/* Linux Classical IP over ATM */
177 #define LINKTYPE_FRELAY		107		/* Frame Relay */
178 #define LINKTYPE_LOOP		108		/* OpenBSD loopback */
179 #define LINKTYPE_ENC		109		/* OpenBSD IPSEC enc */
180 
181 /*
182  * These two types are reserved for future use.
183  */
184 #define LINKTYPE_LANE8023	110		/* ATM LANE + 802.3 */
185 #define LINKTYPE_HIPPI		111		/* NetBSD HIPPI */
186 
187 /*
188  * Used for NetBSD DLT_HDLC; from looking at the one driver in NetBSD
189  * that uses it, it's Cisco HDLC, so it's the same as DLT_C_HDLC/
190  * LINKTYPE_C_HDLC, but we define a separate value to avoid some
191  * compatibility issues with programs on NetBSD.
192  *
193  * All code should treat LINKTYPE_NETBSD_HDLC and LINKTYPE_C_HDLC the same.
194  */
195 #define LINKTYPE_NETBSD_HDLC	112		/* NetBSD HDLC framing */
196 
197 #define LINKTYPE_LINUX_SLL	113		/* Linux cooked socket capture */
198 #define LINKTYPE_LTALK		114		/* Apple LocalTalk hardware */
199 #define LINKTYPE_ECONET		115		/* Acorn Econet */
200 
201 /*
202  * Reserved for use with OpenBSD ipfilter.
203  */
204 #define LINKTYPE_IPFILTER	116
205 
206 #define LINKTYPE_PFLOG		117		/* OpenBSD DLT_PFLOG */
207 #define LINKTYPE_CISCO_IOS	118		/* For Cisco-internal use */
208 #define LINKTYPE_IEEE802_11_PRISM 119		/* 802.11 plus Prism II monitor mode radio metadata header */
209 #define LINKTYPE_IEEE802_11_AIRONET 120		/* 802.11 plus FreeBSD Aironet driver radio metadata header */
210 
211 /*
212  * Reserved for Siemens HiPath HDLC.
213  */
214 #define LINKTYPE_HHDLC		121
215 
216 #define LINKTYPE_IP_OVER_FC	122		/* RFC 2625 IP-over-Fibre Channel */
217 #define LINKTYPE_SUNATM		123		/* Solaris+SunATM */
218 
219 /*
220  * Reserved as per request from Kent Dahlgren <kent@praesum.com>
221  * for private use.
222  */
223 #define LINKTYPE_RIO		124		/* RapidIO */
224 #define LINKTYPE_PCI_EXP	125		/* PCI Express */
225 #define LINKTYPE_AURORA		126		/* Xilinx Aurora link layer */
226 
227 #define LINKTYPE_IEEE802_11_RADIOTAP 127	/* 802.11 plus radiotap radio metadata header */
228 
229 /*
230  * Reserved for the TZSP encapsulation, as per request from
231  * Chris Waters <chris.waters@networkchemistry.com>
232  * TZSP is a generic encapsulation for any other link type,
233  * which includes a means to include meta-information
234  * with the packet, e.g. signal strength and channel
235  * for 802.11 packets.
236  */
237 #define LINKTYPE_TZSP		128		/* Tazmen Sniffer Protocol */
238 
239 #define LINKTYPE_ARCNET_LINUX	129		/* Linux-style headers */
240 
241 /*
242  * Juniper-private data link types, as per request from
243  * Hannes Gredler <hannes@juniper.net>.  The corresponding
244  * DLT_s are used for passing on chassis-internal
245  * metainformation such as QOS profiles, etc..
246  */
247 #define LINKTYPE_JUNIPER_MLPPP  130
248 #define LINKTYPE_JUNIPER_MLFR   131
249 #define LINKTYPE_JUNIPER_ES     132
250 #define LINKTYPE_JUNIPER_GGSN   133
251 #define LINKTYPE_JUNIPER_MFR    134
252 #define LINKTYPE_JUNIPER_ATM2   135
253 #define LINKTYPE_JUNIPER_SERVICES 136
254 #define LINKTYPE_JUNIPER_ATM1   137
255 
256 #define LINKTYPE_APPLE_IP_OVER_IEEE1394 138	/* Apple IP-over-IEEE 1394 cooked header */
257 
258 #define LINKTYPE_MTP2_WITH_PHDR	139
259 #define LINKTYPE_MTP2		140
260 #define LINKTYPE_MTP3		141
261 #define LINKTYPE_SCCP		142
262 
263 #define LINKTYPE_DOCSIS		143		/* DOCSIS MAC frames */
264 
265 #define LINKTYPE_LINUX_IRDA	144		/* Linux-IrDA */
266 
267 /*
268  * Reserved for IBM SP switch and IBM Next Federation switch.
269  */
270 #define LINKTYPE_IBM_SP		145
271 #define LINKTYPE_IBM_SN		146
272 
273 /*
274  * Reserved for private use.  If you have some link-layer header type
275  * that you want to use within your organization, with the capture files
276  * using that link-layer header type not ever be sent outside your
277  * organization, you can use these values.
278  *
279  * No libpcap release will use these for any purpose, nor will any
280  * tcpdump release use them, either.
281  *
282  * Do *NOT* use these in capture files that you expect anybody not using
283  * your private versions of capture-file-reading tools to read; in
284  * particular, do *NOT* use them in products, otherwise you may find that
285  * people won't be able to use tcpdump, or snort, or Ethereal, or... to
286  * read capture files from your firewall/intrusion detection/traffic
287  * monitoring/etc. appliance, or whatever product uses that LINKTYPE_ value,
288  * and you may also find that the developers of those applications will
289  * not accept patches to let them read those files.
290  *
291  * Also, do not use them if somebody might send you a capture using them
292  * for *their* private type and tools using them for *your* private type
293  * would have to read them.
294  *
295  * Instead, in those cases, ask "tcpdump-workers@lists.tcpdump.org" for a
296  * new DLT_ and LINKTYPE_ value, as per the comment in pcap/bpf.h, and use
297  * the type you're given.
298  */
299 #define LINKTYPE_USER0		147
300 #define LINKTYPE_USER1		148
301 #define LINKTYPE_USER2		149
302 #define LINKTYPE_USER3		150
303 #define LINKTYPE_USER4		151
304 #define LINKTYPE_USER5		152
305 #define LINKTYPE_USER6		153
306 #define LINKTYPE_USER7		154
307 #define LINKTYPE_USER8		155
308 #define LINKTYPE_USER9		156
309 #define LINKTYPE_USER10		157
310 #define LINKTYPE_USER11		158
311 #define LINKTYPE_USER12		159
312 #define LINKTYPE_USER13		160
313 #define LINKTYPE_USER14		161
314 #define LINKTYPE_USER15		162
315 
316 /*
317  * For future use with 802.11 captures - defined by AbsoluteValue
318  * Systems to store a number of bits of link-layer information
319  * including radio information:
320  *
321  *	http://www.shaftnet.org/~pizza/software/capturefrm.txt
322  */
323 #define LINKTYPE_IEEE802_11_AVS	163	/* 802.11 plus AVS radio metadata header */
324 
325 /*
326  * Juniper-private data link type, as per request from
327  * Hannes Gredler <hannes@juniper.net>.  The corresponding
328  * DLT_s are used for passing on chassis-internal
329  * metainformation such as QOS profiles, etc..
330  */
331 #define LINKTYPE_JUNIPER_MONITOR 164
332 
333 /*
334  * BACnet MS/TP frames.
335  */
336 #define LINKTYPE_BACNET_MS_TP	165
337 
338 /*
339  * Another PPP variant as per request from Karsten Keil <kkeil@suse.de>.
340  *
341  * This is used in some OSes to allow a kernel socket filter to distinguish
342  * between incoming and outgoing packets, on a socket intended to
343  * supply pppd with outgoing packets so it can do dial-on-demand and
344  * hangup-on-lack-of-demand; incoming packets are filtered out so they
345  * don't cause pppd to hold the connection up (you don't want random
346  * input packets such as port scans, packets from old lost connections,
347  * etc. to force the connection to stay up).
348  *
349  * The first byte of the PPP header (0xff03) is modified to accommodate
350  * the direction - 0x00 = IN, 0x01 = OUT.
351  */
352 #define LINKTYPE_PPP_PPPD	166
353 
354 /*
355  * Juniper-private data link type, as per request from
356  * Hannes Gredler <hannes@juniper.net>.  The DLT_s are used
357  * for passing on chassis-internal metainformation such as
358  * QOS profiles, cookies, etc..
359  */
360 #define LINKTYPE_JUNIPER_PPPOE     167
361 #define LINKTYPE_JUNIPER_PPPOE_ATM 168
362 
363 #define LINKTYPE_GPRS_LLC	169		/* GPRS LLC */
364 #define LINKTYPE_GPF_T		170		/* GPF-T (ITU-T G.7041/Y.1303) */
365 #define LINKTYPE_GPF_F		171		/* GPF-F (ITU-T G.7041/Y.1303) */
366 
367 /*
368  * Requested by Oolan Zimmer <oz@gcom.com> for use in Gcom's T1/E1 line
369  * monitoring equipment.
370  */
371 #define LINKTYPE_GCOM_T1E1	172
372 #define LINKTYPE_GCOM_SERIAL	173
373 
374 /*
375  * Juniper-private data link type, as per request from
376  * Hannes Gredler <hannes@juniper.net>.  The DLT_ is used
377  * for internal communication to Physical Interface Cards (PIC)
378  */
379 #define LINKTYPE_JUNIPER_PIC_PEER    174
380 
381 /*
382  * Link types requested by Gregor Maier <gregor@endace.com> of Endace
383  * Measurement Systems.  They add an ERF header (see
384  * https://www.endace.com/support/EndaceRecordFormat.pdf) in front of
385  * the link-layer header.
386  */
387 #define LINKTYPE_ERF_ETH	175	/* Ethernet */
388 #define LINKTYPE_ERF_POS	176	/* Packet-over-SONET */
389 
390 /*
391  * Requested by Daniele Orlandi <daniele@orlandi.com> for raw LAPD
392  * for vISDN (http://www.orlandi.com/visdn/).  Its link-layer header
393  * includes additional information before the LAPD header, so it's
394  * not necessarily a generic LAPD header.
395  */
396 #define LINKTYPE_LINUX_LAPD	177
397 
398 /*
399  * Juniper-private data link type, as per request from
400  * Hannes Gredler <hannes@juniper.net>.
401  * The Link Types are used for prepending meta-information
402  * like interface index, interface name
403  * before standard Ethernet, PPP, Frelay & C-HDLC Frames
404  */
405 #define LINKTYPE_JUNIPER_ETHER  178
406 #define LINKTYPE_JUNIPER_PPP    179
407 #define LINKTYPE_JUNIPER_FRELAY 180
408 #define LINKTYPE_JUNIPER_CHDLC  181
409 
410 /*
411  * Multi Link Frame Relay (FRF.16)
412  */
413 #define LINKTYPE_MFR            182
414 
415 /*
416  * Juniper-private data link type, as per request from
417  * Hannes Gredler <hannes@juniper.net>.
418  * The DLT_ is used for internal communication with a
419  * voice Adapter Card (PIC)
420  */
421 #define LINKTYPE_JUNIPER_VP     183
422 
423 /*
424  * Arinc 429 frames.
425  * DLT_ requested by Gianluca Varenni <gianluca.varenni@cacetech.com>.
426  * Every frame contains a 32bit A429 label.
427  * More documentation on Arinc 429 can be found at
428  * https://web.archive.org/web/20040616233302/https://www.condoreng.com/support/downloads/tutorials/ARINCTutorial.pdf
429  */
430 #define LINKTYPE_A429           184
431 
432 /*
433  * Arinc 653 Interpartition Communication messages.
434  * DLT_ requested by Gianluca Varenni <gianluca.varenni@cacetech.com>.
435  * Please refer to the A653-1 standard for more information.
436  */
437 #define LINKTYPE_A653_ICM       185
438 
439 /*
440  * This used to be "USB packets, beginning with a USB setup header;
441  * requested by Paolo Abeni <paolo.abeni@email.it>."
442  *
443  * However, that header didn't work all that well - it left out some
444  * useful information - and was abandoned in favor of the DLT_USB_LINUX
445  * header.
446  *
447  * This is now used by FreeBSD for its BPF taps for USB; that has its
448  * own headers.  So it is written, so it is done.
449  */
450 #define LINKTYPE_USB_FREEBSD	186
451 
452 /*
453  * Bluetooth HCI UART transport layer (part H:4); requested by
454  * Paolo Abeni.
455  */
456 #define LINKTYPE_BLUETOOTH_HCI_H4	187
457 
458 /*
459  * IEEE 802.16 MAC Common Part Sublayer; requested by Maria Cruz
460  * <cruz_petagay@bah.com>.
461  */
462 #define LINKTYPE_IEEE802_16_MAC_CPS	188
463 
464 /*
465  * USB packets, beginning with a Linux USB header; requested by
466  * Paolo Abeni <paolo.abeni@email.it>.
467  */
468 #define LINKTYPE_USB_LINUX		189
469 
470 /*
471  * Controller Area Network (CAN) v. 2.0B packets.
472  * DLT_ requested by Gianluca Varenni <gianluca.varenni@cacetech.com>.
473  * Used to dump CAN packets coming from a CAN Vector board.
474  * More documentation on the CAN v2.0B frames can be found at
475  * http://www.can-cia.org/downloads/?269
476  */
477 #define LINKTYPE_CAN20B         190
478 
479 /*
480  * IEEE 802.15.4, with address fields padded, as is done by Linux
481  * drivers; requested by Juergen Schimmer.
482  */
483 #define LINKTYPE_IEEE802_15_4_LINUX	191
484 
485 /*
486  * Per Packet Information encapsulated packets.
487  * LINKTYPE_ requested by Gianluca Varenni <gianluca.varenni@cacetech.com>.
488  */
489 #define LINKTYPE_PPI			192
490 
491 /*
492  * Header for 802.16 MAC Common Part Sublayer plus a radiotap radio header;
493  * requested by Charles Clancy.
494  */
495 #define LINKTYPE_IEEE802_16_MAC_CPS_RADIO	193
496 
497 /*
498  * Juniper-private data link type, as per request from
499  * Hannes Gredler <hannes@juniper.net>.
500  * The DLT_ is used for internal communication with a
501  * integrated service module (ISM).
502  */
503 #define LINKTYPE_JUNIPER_ISM    194
504 
505 /*
506  * IEEE 802.15.4, exactly as it appears in the spec (no padding, no
507  * nothing), and with the FCS at the end of the frame; requested by
508  * Mikko Saarnivala <mikko.saarnivala@sensinode.com>.
509  *
510  * This should only be used if the FCS is present at the end of the
511  * frame; if the frame has no FCS, DLT_IEEE802_15_4_NOFCS should be
512  * used.
513  */
514 #define LINKTYPE_IEEE802_15_4_WITHFCS	195
515 
516 /*
517  * Various link-layer types, with a pseudo-header, for SITA
518  * (https://www.sita.aero/); requested by Fulko Hew (fulko.hew@gmail.com).
519  */
520 #define LINKTYPE_SITA		196
521 
522 /*
523  * Various link-layer types, with a pseudo-header, for Endace DAG cards;
524  * encapsulates Endace ERF records.  Requested by Stephen Donnelly
525  * <stephen@endace.com>.
526  */
527 #define LINKTYPE_ERF		197
528 
529 /*
530  * Special header prepended to Ethernet packets when capturing from a
531  * u10 Networks board.  Requested by Phil Mulholland
532  * <phil@u10networks.com>.
533  */
534 #define LINKTYPE_RAIF1		198
535 
536 /*
537  * IPMB packet for IPMI, beginning with a 2-byte header, followed by
538  * the I2C slave address, followed by the netFn and LUN, etc..
539  * Requested by Chanthy Toeung <chanthy.toeung@ca.kontron.com>.
540  *
541  * XXX - its DLT_ value used to be called DLT_IPMB, back when we got the
542  * impression from the email thread requesting it that the packet
543  * had no extra 2-byte header.  We've renamed it; if anybody used
544  * DLT_IPMB and assumed no 2-byte header, this will cause the compile
545  * to fail, at which point we'll have to figure out what to do about
546  * the two header types using the same DLT_/LINKTYPE_ value.  If that
547  * doesn't happen, we'll assume nobody used it and that the redefinition
548  * is safe.
549  */
550 #define LINKTYPE_IPMB_KONTRON	199
551 
552 /*
553  * Juniper-private data link type, as per request from
554  * Hannes Gredler <hannes@juniper.net>.
555  * The DLT_ is used for capturing data on a secure tunnel interface.
556  */
557 #define LINKTYPE_JUNIPER_ST     200
558 
559 /*
560  * Bluetooth HCI UART transport layer (part H:4), with pseudo-header
561  * that includes direction information; requested by Paolo Abeni.
562  */
563 #define LINKTYPE_BLUETOOTH_HCI_H4_WITH_PHDR	201
564 
565 /*
566  * AX.25 packet with a 1-byte KISS header; see
567  *
568  *	http://www.ax25.net/kiss.htm
569  *
570  * as per Richard Stearn <richard@rns-stearn.demon.co.uk>.
571  */
572 #define LINKTYPE_AX25_KISS	202
573 
574 /*
575  * LAPD packets from an ISDN channel, starting with the address field,
576  * with no pseudo-header.
577  * Requested by Varuna De Silva <varunax@gmail.com>.
578  */
579 #define LINKTYPE_LAPD		203
580 
581 /*
582  * PPP, with a one-byte direction pseudo-header prepended - zero means
583  * "received by this host", non-zero (any non-zero value) means "sent by
584  * this host" - as per Will Barker <w.barker@zen.co.uk>.
585  */
586 #define LINKTYPE_PPP_WITH_DIR	204	/* Don't confuse with LINKTYPE_PPP_PPPD */
587 
588 /*
589  * Cisco HDLC, with a one-byte direction pseudo-header prepended - zero
590  * means "received by this host", non-zero (any non-zero value) means
591  * "sent by this host" - as per Will Barker <w.barker@zen.co.uk>.
592  */
593 #define LINKTYPE_C_HDLC_WITH_DIR 205	/* Cisco HDLC */
594 
595 /*
596  * Frame Relay, with a one-byte direction pseudo-header prepended - zero
597  * means "received by this host" (DCE -> DTE), non-zero (any non-zero
598  * value) means "sent by this host" (DTE -> DCE) - as per Will Barker
599  * <w.barker@zen.co.uk>.
600  */
601 #define LINKTYPE_FRELAY_WITH_DIR 206	/* Frame Relay */
602 
603 /*
604  * LAPB, with a one-byte direction pseudo-header prepended - zero means
605  * "received by this host" (DCE -> DTE), non-zero (any non-zero value)
606  * means "sent by this host" (DTE -> DCE)- as per Will Barker
607  * <w.barker@zen.co.uk>.
608  */
609 #define LINKTYPE_LAPB_WITH_DIR	207	/* LAPB */
610 
611 /*
612  * 208 is reserved for an as-yet-unspecified proprietary link-layer
613  * type, as requested by Will Barker.
614  */
615 
616 /*
617  * IPMB with a Linux-specific pseudo-header; as requested by Alexey Neyman
618  * <avn@pigeonpoint.com>.
619  */
620 #define LINKTYPE_IPMB_LINUX	209
621 
622 /*
623  * FlexRay automotive bus - http://www.flexray.com/ - as requested
624  * by Hannes Kaelber <hannes.kaelber@x2e.de>.
625  */
626 #define LINKTYPE_FLEXRAY	210
627 
628 /*
629  * Media Oriented Systems Transport (MOST) bus for multimedia
630  * transport - https://www.mostcooperation.com/ - as requested
631  * by Hannes Kaelber <hannes.kaelber@x2e.de>.
632  */
633 #define LINKTYPE_MOST		211
634 
635 /*
636  * Local Interconnect Network (LIN) bus for vehicle networks -
637  * http://www.lin-subbus.org/ - as requested by Hannes Kaelber
638  * <hannes.kaelber@x2e.de>.
639  */
640 #define LINKTYPE_LIN		212
641 
642 /*
643  * X2E-private data link type used for serial line capture,
644  * as requested by Hannes Kaelber <hannes.kaelber@x2e.de>.
645  */
646 #define LINKTYPE_X2E_SERIAL	213
647 
648 /*
649  * X2E-private data link type used for the Xoraya data logger
650  * family, as requested by Hannes Kaelber <hannes.kaelber@x2e.de>.
651  */
652 #define LINKTYPE_X2E_XORAYA	214
653 
654 /*
655  * IEEE 802.15.4, exactly as it appears in the spec (no padding, no
656  * nothing), but with the PHY-level data for non-ASK PHYs (4 octets
657  * of 0 as preamble, one octet of SFD, one octet of frame length+
658  * reserved bit, and then the MAC-layer data, starting with the
659  * frame control field).
660  *
661  * Requested by Max Filippov <jcmvbkbc@gmail.com>.
662  */
663 #define LINKTYPE_IEEE802_15_4_NONASK_PHY	215
664 
665 /*
666  * David Gibson <david@gibson.dropbear.id.au> requested this for
667  * captures from the Linux kernel /dev/input/eventN devices. This
668  * is used to communicate keystrokes and mouse movements from the
669  * Linux kernel to display systems, such as Xorg.
670  */
671 #define LINKTYPE_LINUX_EVDEV	216
672 
673 /*
674  * GSM Um and Abis interfaces, preceded by a "gsmtap" header.
675  *
676  * Requested by Harald Welte <laforge@gnumonks.org>.
677  */
678 #define LINKTYPE_GSMTAP_UM	217
679 #define LINKTYPE_GSMTAP_ABIS	218
680 
681 /*
682  * MPLS, with an MPLS label as the link-layer header.
683  * Requested by Michele Marchetto <michele@openbsd.org> on behalf
684  * of OpenBSD.
685  */
686 #define LINKTYPE_MPLS		219
687 
688 /*
689  * USB packets, beginning with a Linux USB header, with the USB header
690  * padded to 64 bytes; required for memory-mapped access.
691  */
692 #define LINKTYPE_USB_LINUX_MMAPPED		220
693 
694 /*
695  * DECT packets, with a pseudo-header; requested by
696  * Matthias Wenzel <tcpdump@mazzoo.de>.
697  */
698 #define LINKTYPE_DECT		221
699 
700 /*
701  * From: "Lidwa, Eric (GSFC-582.0)[SGT INC]" <eric.lidwa-1@nasa.gov>
702  * Date: Mon, 11 May 2009 11:18:30 -0500
703  *
704  * DLT_AOS. We need it for AOS Space Data Link Protocol.
705  *   I have already written dissectors for but need an OK from
706  *   legal before I can submit a patch.
707  *
708  */
709 #define LINKTYPE_AOS		222
710 
711 /*
712  * WirelessHART (Highway Addressable Remote Transducer)
713  * From the HART Communication Foundation
714  * IEC/PAS 62591
715  *
716  * Requested by Sam Roberts <vieuxtech@gmail.com>.
717  */
718 #define LINKTYPE_WIHART		223
719 
720 /*
721  * Fibre Channel FC-2 frames, beginning with a Frame_Header.
722  * Requested by Kahou Lei <kahou82@gmail.com>.
723  */
724 #define LINKTYPE_FC_2		224
725 
726 /*
727  * Fibre Channel FC-2 frames, beginning with an encoding of the
728  * SOF, and ending with an encoding of the EOF.
729  *
730  * The encodings represent the frame delimiters as 4-byte sequences
731  * representing the corresponding ordered sets, with K28.5
732  * represented as 0xBC, and the D symbols as the corresponding
733  * byte values; for example, SOFi2, which is K28.5 - D21.5 - D1.2 - D21.2,
734  * is represented as 0xBC 0xB5 0x55 0x55.
735  *
736  * Requested by Kahou Lei <kahou82@gmail.com>.
737  */
738 #define LINKTYPE_FC_2_WITH_FRAME_DELIMS		225
739 
740 /*
741  * Solaris ipnet pseudo-header; requested by Darren Reed <Darren.Reed@Sun.COM>.
742  *
743  * The pseudo-header starts with a one-byte version number; for version 2,
744  * the pseudo-header is:
745  *
746  * struct dl_ipnetinfo {
747  *     uint8_t   dli_version;
748  *     uint8_t   dli_family;
749  *     uint16_t  dli_htype;
750  *     uint32_t  dli_pktlen;
751  *     uint32_t  dli_ifindex;
752  *     uint32_t  dli_grifindex;
753  *     uint32_t  dli_zsrc;
754  *     uint32_t  dli_zdst;
755  * };
756  *
757  * dli_version is 2 for the current version of the pseudo-header.
758  *
759  * dli_family is a Solaris address family value, so it's 2 for IPv4
760  * and 26 for IPv6.
761  *
762  * dli_htype is a "hook type" - 0 for incoming packets, 1 for outgoing
763  * packets, and 2 for packets arriving from another zone on the same
764  * machine.
765  *
766  * dli_pktlen is the length of the packet data following the pseudo-header
767  * (so the captured length minus dli_pktlen is the length of the
768  * pseudo-header, assuming the entire pseudo-header was captured).
769  *
770  * dli_ifindex is the interface index of the interface on which the
771  * packet arrived.
772  *
773  * dli_grifindex is the group interface index number (for IPMP interfaces).
774  *
775  * dli_zsrc is the zone identifier for the source of the packet.
776  *
777  * dli_zdst is the zone identifier for the destination of the packet.
778  *
779  * A zone number of 0 is the global zone; a zone number of 0xffffffff
780  * means that the packet arrived from another host on the network, not
781  * from another zone on the same machine.
782  *
783  * An IPv4 or IPv6 datagram follows the pseudo-header; dli_family indicates
784  * which of those it is.
785  */
786 #define LINKTYPE_IPNET		226
787 
788 /*
789  * CAN (Controller Area Network) frames, with a pseudo-header as supplied
790  * by Linux SocketCAN, and with multi-byte numerical fields in that header
791  * in big-endian byte order.
792  *
793  * See Documentation/networking/can.txt in the Linux source.
794  *
795  * Requested by Felix Obenhuber <felix@obenhuber.de>.
796  */
797 #define LINKTYPE_CAN_SOCKETCAN	227
798 
799 /*
800  * Raw IPv4/IPv6; different from DLT_RAW in that the DLT_ value specifies
801  * whether it's v4 or v6.  Requested by Darren Reed <Darren.Reed@Sun.COM>.
802  */
803 #define LINKTYPE_IPV4		228
804 #define LINKTYPE_IPV6		229
805 
806 /*
807  * IEEE 802.15.4, exactly as it appears in the spec (no padding, no
808  * nothing), and with no FCS at the end of the frame; requested by
809  * Jon Smirl <jonsmirl@gmail.com>.
810  */
811 #define LINKTYPE_IEEE802_15_4_NOFCS		230
812 
813 /*
814  * Raw D-Bus:
815  *
816  *	https://www.freedesktop.org/wiki/Software/dbus
817  *
818  * messages:
819  *
820  *	https://dbus.freedesktop.org/doc/dbus-specification.html#message-protocol-messages
821  *
822  * starting with the endianness flag, followed by the message type, etc.,
823  * but without the authentication handshake before the message sequence:
824  *
825  *	https://dbus.freedesktop.org/doc/dbus-specification.html#auth-protocol
826  *
827  * Requested by Martin Vidner <martin@vidner.net>.
828  */
829 #define LINKTYPE_DBUS		231
830 
831 /*
832  * Juniper-private data link type, as per request from
833  * Hannes Gredler <hannes@juniper.net>.
834  */
835 #define LINKTYPE_JUNIPER_VS			232
836 #define LINKTYPE_JUNIPER_SRX_E2E		233
837 #define LINKTYPE_JUNIPER_FIBRECHANNEL		234
838 
839 /*
840  * DVB-CI (DVB Common Interface for communication between a PC Card
841  * module and a DVB receiver).  See
842  *
843  *	https://www.kaiser.cx/pcap-dvbci.html
844  *
845  * for the specification.
846  *
847  * Requested by Martin Kaiser <martin@kaiser.cx>.
848  */
849 #define LINKTYPE_DVB_CI		235
850 
851 /*
852  * Variant of 3GPP TS 27.010 multiplexing protocol.  Requested
853  * by Hans-Christoph Schemmel <hans-christoph.schemmel@cinterion.com>.
854  */
855 #define LINKTYPE_MUX27010	236
856 
857 /*
858  * STANAG 5066 D_PDUs.  Requested by M. Baris Demiray
859  * <barisdemiray@gmail.com>.
860  */
861 #define LINKTYPE_STANAG_5066_D_PDU		237
862 
863 /*
864  * Juniper-private data link type, as per request from
865  * Hannes Gredler <hannes@juniper.net>.
866  */
867 #define LINKTYPE_JUNIPER_ATM_CEMIC		238
868 
869 /*
870  * NetFilter LOG messages
871  * (payload of netlink NFNL_SUBSYS_ULOG/NFULNL_MSG_PACKET packets)
872  *
873  * Requested by Jakub Zawadzki <darkjames-ws@darkjames.pl>
874  */
875 #define LINKTYPE_NFLOG		239
876 
877 /*
878  * Hilscher Gesellschaft fuer Systemautomation mbH link-layer type
879  * for Ethernet packets with a 4-byte pseudo-header and always
880  * with the payload including the FCS, as supplied by their
881  * netANALYZER hardware and software.
882  *
883  * Requested by Holger P. Frommer <HPfrommer@hilscher.com>
884  */
885 #define LINKTYPE_NETANALYZER	240
886 
887 /*
888  * Hilscher Gesellschaft fuer Systemautomation mbH link-layer type
889  * for Ethernet packets with a 4-byte pseudo-header and FCS and
890  * 1 byte of SFD, as supplied by their netANALYZER hardware and
891  * software.
892  *
893  * Requested by Holger P. Frommer <HPfrommer@hilscher.com>
894  */
895 #define LINKTYPE_NETANALYZER_TRANSPARENT	241
896 
897 /*
898  * IP-over-InfiniBand, as specified by RFC 4391.
899  *
900  * Requested by Petr Sumbera <petr.sumbera@oracle.com>.
901  */
902 #define LINKTYPE_IPOIB		242
903 
904 /*
905  * MPEG-2 transport stream (ISO 13818-1/ITU-T H.222.0).
906  *
907  * Requested by Guy Martin <gmsoft@tuxicoman.be>.
908  */
909 #define LINKTYPE_MPEG_2_TS	243
910 
911 /*
912  * ng4T GmbH's UMTS Iub/Iur-over-ATM and Iub/Iur-over-IP format as
913  * used by their ng40 protocol tester.
914  *
915  * Requested by Jens Grimmer <jens.grimmer@ng4t.com>.
916  */
917 #define LINKTYPE_NG40		244
918 
919 /*
920  * Pseudo-header giving adapter number and flags, followed by an NFC
921  * (Near-Field Communications) Logical Link Control Protocol (LLCP) PDU,
922  * as specified by NFC Forum Logical Link Control Protocol Technical
923  * Specification LLCP 1.1.
924  *
925  * Requested by Mike Wakerly <mikey@google.com>.
926  */
927 #define LINKTYPE_NFC_LLCP	245
928 
929 /*
930  * pfsync output; DLT_PFSYNC is 18, which collides with DLT_CIP in
931  * SuSE 6.3, on OpenBSD, NetBSD, DragonFly BSD, and macOS, and
932  * is 121, which collides with DLT_HHDLC, in FreeBSD.  We pick a
933  * shiny new link-layer header type value that doesn't collide with
934  * anything, in the hopes that future pfsync savefiles, if any,
935  * won't require special hacks to distinguish from other savefiles.
936  */
937 #define LINKTYPE_PFSYNC		246
938 
939 /*
940  * Raw InfiniBand packets, starting with the Local Routing Header.
941  *
942  * Requested by Oren Kladnitsky <orenk@mellanox.com>.
943  */
944 #define LINKTYPE_INFINIBAND	247
945 
946 /*
947  * SCTP, with no lower-level protocols (i.e., no IPv4 or IPv6).
948  *
949  * Requested by Michael Tuexen <Michael.Tuexen@lurchi.franken.de>.
950  */
951 #define LINKTYPE_SCTP		248
952 
953 /*
954  * USB packets, beginning with a USBPcap header.
955  *
956  * Requested by Tomasz Mon <desowin@gmail.com>
957  */
958 #define LINKTYPE_USBPCAP	249
959 
960 /*
961  * Schweitzer Engineering Laboratories "RTAC" product serial-line
962  * packets.
963  *
964  * Requested by Chris Bontje <chris_bontje@selinc.com>.
965  */
966 #define LINKTYPE_RTAC_SERIAL		250
967 
968 /*
969  * Bluetooth Low Energy air interface link-layer packets.
970  *
971  * Requested by Mike Kershaw <dragorn@kismetwireless.net>.
972  */
973 #define LINKTYPE_BLUETOOTH_LE_LL	251
974 
975 /*
976  * Link-layer header type for upper-protocol layer PDU saves from wireshark.
977  *
978  * the actual contents are determined by two TAGs, one or more of
979  * which is stored with each packet:
980  *
981  *   EXP_PDU_TAG_DISSECTOR_NAME      the name of the Wireshark dissector
982  *				     that can make sense of the data stored.
983  *
984  *   EXP_PDU_TAG_HEUR_DISSECTOR_NAME the name of the Wireshark heuristic
985  *				     dissector that can make sense of the
986  *				     data stored.
987  */
988 #define LINKTYPE_WIRESHARK_UPPER_PDU	252
989 
990 /*
991  * Link-layer header type for the netlink protocol (nlmon devices).
992  */
993 #define LINKTYPE_NETLINK		253
994 
995 /*
996  * Bluetooth Linux Monitor headers for the BlueZ stack.
997  */
998 #define LINKTYPE_BLUETOOTH_LINUX_MONITOR	254
999 
1000 /*
1001  * Bluetooth Basic Rate/Enhanced Data Rate baseband packets, as
1002  * captured by Ubertooth.
1003  */
1004 #define LINKTYPE_BLUETOOTH_BREDR_BB	255
1005 
1006 /*
1007  * Bluetooth Low Energy link layer packets, as captured by Ubertooth.
1008  */
1009 #define LINKTYPE_BLUETOOTH_LE_LL_WITH_PHDR	256
1010 
1011 /*
1012  * PROFIBUS data link layer.
1013  */
1014 #define LINKTYPE_PROFIBUS_DL		257
1015 
1016 /*
1017  * Apple's DLT_PKTAP headers.
1018  *
1019  * Sadly, the folks at Apple either had no clue that the DLT_USERn values
1020  * are for internal use within an organization and partners only, and
1021  * didn't know that the right way to get a link-layer header type is to
1022  * ask tcpdump.org for one, or knew and didn't care, so they just
1023  * used DLT_USER2, which causes problems for everything except for
1024  * their version of tcpdump.
1025  *
1026  * So I'll just give them one; hopefully this will show up in a
1027  * libpcap release in time for them to get this into 10.10 Big Sur
1028  * or whatever Mavericks' successor is called.  LINKTYPE_PKTAP
1029  * will be 258 *even on macOS*; that is *intentional*, so that
1030  * PKTAP files look the same on *all* OSes (different OSes can have
1031  * different numerical values for a given DLT_, but *MUST NOT* have
1032  * different values for what goes in a file, as files can be moved
1033  * between OSes!).
1034  */
1035 #define LINKTYPE_PKTAP		258
1036 
1037 /*
1038  * Ethernet packets preceded by a header giving the last 6 octets
1039  * of the preamble specified by 802.3-2012 Clause 65, section
1040  * 65.1.3.2 "Transmit".
1041  */
1042 #define LINKTYPE_EPON		259
1043 
1044 /*
1045  * IPMI trace packets, as specified by Table 3-20 "Trace Data Block Format"
1046  * in the PICMG HPM.2 specification.
1047  */
1048 #define LINKTYPE_IPMI_HPM_2	260
1049 
1050 /*
1051  * per  Joshua Wright <jwright@hasborg.com>, formats for Zwave captures.
1052  */
1053 #define LINKTYPE_ZWAVE_R1_R2	261
1054 #define LINKTYPE_ZWAVE_R3	262
1055 
1056 /*
1057  * per Steve Karg <skarg@users.sourceforge.net>, formats for Wattstopper
1058  * Digital Lighting Management room bus serial protocol captures.
1059  */
1060 #define LINKTYPE_WATTSTOPPER_DLM 263
1061 
1062 /*
1063  * ISO 14443 contactless smart card messages.
1064  */
1065 #define LINKTYPE_ISO_14443      264
1066 
1067 /*
1068  * Radio data system (RDS) groups.  IEC 62106.
1069  * Per Jonathan Brucker <jonathan.brucke@gmail.com>.
1070  */
1071 #define LINKTYPE_RDS		265
1072 
1073 /*
1074  * USB packets, beginning with a Darwin (macOS, etc.) header.
1075  */
1076 #define LINKTYPE_USB_DARWIN	266
1077 
1078 /*
1079  * OpenBSD DLT_OPENFLOW.
1080  */
1081 #define LINKTYPE_OPENFLOW	267
1082 
1083 /*
1084  * SDLC frames containing SNA PDUs.
1085  */
1086 #define LINKTYPE_SDLC		268
1087 
1088 /*
1089  * per "Selvig, Bjorn" <b.selvig@ti.com> used for
1090  * TI protocol sniffer.
1091  */
1092 #define LINKTYPE_TI_LLN_SNIFFER	269
1093 
1094 /*
1095  * per: Erik de Jong <erikdejong at gmail.com> for
1096  *   https://github.com/eriknl/LoRaTap/releases/tag/v0.1
1097  */
1098 #define LINKTYPE_LORATAP        270
1099 
1100 /*
1101  * per: Stefanha at gmail.com for
1102  *   https://lists.sandelman.ca/pipermail/tcpdump-workers/2017-May/000772.html
1103  * and: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/include/uapi/linux/vsockmon.h
1104  * for: https://qemu-project.org/Features/VirtioVsock
1105  */
1106 #define LINKTYPE_VSOCK          271
1107 
1108 /*
1109  * Nordic Semiconductor Bluetooth LE sniffer.
1110  */
1111 #define LINKTYPE_NORDIC_BLE	272
1112 
1113 /*
1114  * Excentis DOCSIS 3.1 RF sniffer (XRA-31)
1115  *   per: bruno.verstuyft at excentis.com
1116  *        https://www.xra31.com/xra-header
1117  */
1118 #define LINKTYPE_DOCSIS31_XRA31	273
1119 
1120 /*
1121  * mPackets, as specified by IEEE 802.3br Figure 99-4, starting
1122  * with the preamble and always ending with a CRC field.
1123  */
1124 #define LINKTYPE_ETHERNET_MPACKET	274
1125 
1126 /*
1127  * DisplayPort AUX channel monitoring data as specified by VESA
1128  * DisplayPort(DP) Standard preceded by a pseudo-header.
1129  *    per dirk.eibach at gdsys.cc
1130  */
1131 #define LINKTYPE_DISPLAYPORT_AUX	275
1132 
1133 /*
1134  * Linux cooked sockets v2.
1135  */
1136 #define LINKTYPE_LINUX_SLL2	276
1137 
1138 /*
1139  * Sercos Monitor, per Manuel Jacob <manuel.jacob at steinbeis-stg.de>
1140  */
1141 #define LINKTYPE_SERCOS_MONITOR 277
1142 
1143 /*
1144  * OpenVizsla http://openvizsla.org is open source USB analyzer hardware.
1145  * It consists of FPGA with attached USB phy and FTDI chip for streaming
1146  * the data to the host PC.
1147  *
1148  * Current OpenVizsla data encapsulation format is described here:
1149  * https://github.com/matwey/libopenvizsla/wiki/OpenVizsla-protocol-description
1150  *
1151  */
1152 #define LINKTYPE_OPENVIZSLA     278
1153 
1154 /*
1155  * The Elektrobit High Speed Capture and Replay (EBHSCR) protocol is produced
1156  * by a PCIe Card for interfacing high speed automotive interfaces.
1157  *
1158  * The specification for this frame format can be found at:
1159  *   https://www.elektrobit.com/ebhscr
1160  *
1161  * for Guenter.Ebermann at elektrobit.com
1162  *
1163  */
1164 #define LINKTYPE_EBHSCR	        279
1165 
1166 /*
1167  * The https://fd.io vpp graph dispatch tracer produces pcap trace files
1168  * in the format documented here:
1169  * https://fdio-vpp.readthedocs.io/en/latest/gettingstarted/developers/vnet.html#graph-dispatcher-pcap-tracing
1170  */
1171 #define LINKTYPE_VPP_DISPATCH	280
1172 
1173 /*
1174  * Broadcom Ethernet switches (ROBO switch) 4 bytes proprietary tagging format.
1175  */
1176 #define LINKTYPE_DSA_TAG_BRCM	281
1177 #define LINKTYPE_DSA_TAG_BRCM_PREPEND	282
1178 
1179 /*
1180  * IEEE 802.15.4 with pseudo-header and optional meta-data TLVs, PHY payload
1181  * exactly as it appears in the spec (no padding, no nothing), and FCS if
1182  * specified by FCS Type TLV;  requested by James Ko <jck@exegin.com>.
1183  * Specification at https://github.com/jkcko/ieee802.15.4-tap
1184  */
1185 #define LINKTYPE_IEEE802_15_4_TAP       283
1186 
1187 /*
1188  * Marvell (Ethertype) Distributed Switch Architecture proprietary tagging format.
1189  */
1190 #define LINKTYPE_DSA_TAG_DSA	284
1191 #define LINKTYPE_DSA_TAG_EDSA	285
1192 
1193 /*
1194  * Payload of lawful intercept packets using the ELEE protocol;
1195  * https://socket.hr/draft-dfranusic-opsawg-elee-00.xml
1196  * https://xml2rfc.tools.ietf.org/cgi-bin/xml2rfc.cgi?url=https://socket.hr/draft-dfranusic-opsawg-elee-00.xml&modeAsFormat=html/ascii
1197  */
1198 #define LINKTYPE_ELEE		286
1199 
1200 /*
1201  * Serial frames transmitted between a host and a Z-Wave chip.
1202  */
1203 #define LINKTYPE_Z_WAVE_SERIAL	287
1204 
1205 /*
1206  * USB 2.0, 1.1, and 1.0 packets as transmitted over the cable.
1207  */
1208 #define LINKTYPE_USB_2_0	288
1209 
1210 /*
1211  * ATSC Link-Layer Protocol (A/330) packets.
1212  */
1213 #define LINKTYPE_ATSC_ALP	289
1214 
1215 #define LINKTYPE_HIGH_MATCHING_MAX	289		/* highest value in the "matching" range */
1216 
1217 /*
1218  * The DLT_ and LINKTYPE_ values in the "matching" range should be the
1219  * same, so DLT_HIGH_MATCHING_MAX and LINKTYPE_HIGH_MATCHING_MAX should be the
1220  * same.
1221  */
1222 #if LINKTYPE_HIGH_MATCHING_MAX != DLT_HIGH_MATCHING_MAX
1223 #error The LINKTYPE_ high matching range does not match the DLT_ matching range
1224 #endif
1225 
1226 /*
1227  * Map a DLT_* code to the corresponding LINKTYPE_* code.
1228  * Used to generate link-layer types written to savefiles.
1229  */
1230 int
1231 dlt_to_linktype(int dlt)
1232 {
1233 	/*
1234 	 * All values in the low matching range were handed out before
1235 	 * assigning DLT_* codes became a free-for-all, so they're the
1236 	 * same on all platforms, and thus are given LINKTYPE_* codes
1237 	 * with the same numerical values as the corresponding DLT_*
1238 	 * code.
1239 	 */
1240 	if (dlt >= DLT_LOW_MATCHING_MIN && dlt <= DLT_LOW_MATCHING_MAX)
1241 		return (dlt);
1242 
1243 #if DLT_PFSYNC != LINKTYPE_PFSYNC
1244 	/*
1245 	 * DLT_PFSYNC has a code on several platforms that's in the
1246 	 * non-matching range, a code on FreeBSD that's in the high
1247 	 * matching range and that's *not* equal to LINKTYPE_PFSYNC,
1248 	 * and has a code on the rmaining platforms that's equal
1249 	 * to LINKTYPE_PFSYNC, which is in the high matching range.
1250 	 *
1251 	 * Map it to LINKTYPE_PFSYNC if it's not equal to LINKTYPE_PFSYNC.
1252 	 */
1253 	if (dlt == DLT_PFSYNC)
1254 		return (LINKTYPE_PFSYNC);
1255 #endif
1256 
1257 	/*
1258 	 * DLT_PKTAP is defined as DLT_USER2 - which is in the high
1259 	 * matching range - on Darwin because Apple used DLT_USER2
1260 	 * on systems that users ran, not just as an internal thing.
1261 	 *
1262 	 * We map it to LINKTYPE_PKTAP if it's not equal to LINKTYPE_PKTAP
1263 	 * so that DLT_PKTAP captures from Apple machines can be read by
1264 	 * software that either doesn't handle DLT_USER2 or that handles it
1265 	 * as something other than Apple PKTAP.
1266 	 */
1267 #if DLT_PKTAP != LINKTYPE_PKTAP
1268 	if (dlt == DLT_PKTAP)
1269 		return (LINKTYPE_PKTAP);
1270 #endif
1271 
1272 	/*
1273 	 * For all other DLT_* codes in the high matching range, the DLT
1274 	 * code value is the same as the LINKTYPE_* code value.
1275 	 */
1276 	if (dlt >= DLT_HIGH_MATCHING_MIN && dlt <= DLT_HIGH_MATCHING_MAX)
1277 		return (dlt);
1278 
1279 	/*
1280 	 * These DLT_* codes have different values on different
1281 	 * platforms, so we assigned them LINKTYPE_* codes just
1282 	 * below the lower bound of the high matchig range;
1283 	 * those values should never be equal to any DLT_*
1284 	 * code, so that should avoid collisions.
1285 	 *
1286 	 * That way, for example, "raw IP" packets will have
1287 	 * LINKTYPE_RAW as the code in all savefiles for
1288 	 * which the code that writes them maps to that
1289 	 * value, regardless of the platform on which they
1290 	 * were written, so they should be readable on all
1291 	 * platforms without having to determine on which
1292 	 * platform they were written.
1293 	 *
1294 	 * We map the DLT_* codes on this platform, whatever
1295 	 * it might be, to the corresponding LINKTYPE_* codes.
1296 	 */
1297 	if (dlt == DLT_ATM_RFC1483)
1298 		return (LINKTYPE_ATM_RFC1483);
1299 	if (dlt == DLT_RAW)
1300 		return (LINKTYPE_RAW);
1301 	if (dlt == DLT_SLIP_BSDOS)
1302 		return (LINKTYPE_SLIP_BSDOS);
1303 	if (dlt == DLT_PPP_BSDOS)
1304 		return (LINKTYPE_PPP_BSDOS);
1305 
1306 	/*
1307 	 * These DLT_* codes were originally defined on some platform,
1308 	 * and weren't defined on other platforms.
1309 	 *
1310 	 * At least some of them have values, on at least one platform,
1311 	 * that collide with other DLT_* codes on other platforms, e.g.
1312 	 * DLT_LOOP, so we don't just define them, on all platforms,
1313 	 * as having the same value as on the original platform.
1314 	 *
1315 	 * Therefore, we assigned new LINKTYPE_* codes to them, and,
1316 	 * on the platforms where they weren't originally defined,
1317 	 * define the DLT_* codes to have the same value as the
1318 	 * corresponding LINKTYPE_* codes.
1319 	 *
1320 	 * This means that, for capture files with the original
1321 	 * platform's DLT_* code rather than the LINKTYPE_* code
1322 	 * as a link-layer type, we will recognize those types
1323 	 * on that platform, but not on other platforms.
1324 	 */
1325 #ifdef DLT_FR
1326 	/* BSD/OS Frame Relay */
1327 	if (dlt == DLT_FR)
1328 		return (LINKTYPE_FRELAY);
1329 #endif
1330 #if DLT_HDLC != LINKTYPE_NETBSD_HDLC
1331 	/* NetBSD HDLC */
1332 	if (dlt == DLT_HDLC)
1333 		return (LINKTYPE_NETBSD_HDLC);
1334 #endif
1335 #if DLT_C_HDLC != LINKTYPE_C_HDLC
1336 	/* BSD/OS Cisco HDLC */
1337 	if (dlt == DLT_C_HDLC)
1338 		return (LINKTYPE_C_HDLC);
1339 #endif
1340 #if DLT_LOOP != LINKTYPE_LOOP
1341 	/* OpenBSD DLT_LOOP */
1342 	if (dlt == DLT_LOOP)
1343 		return (LINKTYPE_LOOP);
1344 #endif
1345 #if DLT_ENC != LINKTYPE_ENC
1346 	/* OpenBSD DLT_ENC */
1347 	if (dlt == DLT_ENC)
1348 		return (LINKTYPE_ENC);
1349 #endif
1350 
1351 	/*
1352 	 * These DLT_* codes are not on all platforms, but, so far,
1353 	 * there don't appear to be any platforms that define
1354 	 * other codes with those values; we map them to
1355 	 * different LINKTYPE_* codes anyway, just in case.
1356 	 */
1357 	/* Linux ATM Classical IP */
1358 	if (dlt == DLT_ATM_CLIP)
1359 		return (LINKTYPE_ATM_CLIP);
1360 
1361 	/*
1362 	 * A few other values, defined on some platforms, not in
1363 	 * either matching range, but not colliding with anything
1364 	 * else, so they're given the same LINKTYPE_* code as
1365 	 * their DLT_* code.
1366 	 */
1367 	if (dlt == DLT_REDBACK_SMARTEDGE || dlt == DLT_PPP_SERIAL ||
1368 	    dlt == DLT_PPP_ETHER || dlt == DLT_SYMANTEC_FIREWALL)
1369 		return (dlt);
1370 
1371 	/*
1372 	 * If we don't have a mapping for this DLT_* code, return an
1373 	 * error; that means that this is a DLT_* value with no
1374 	 * corresponding LINKTYPE_ value, and we need to assign one.
1375 	 */
1376 	return (-1);
1377 }
1378 
1379 /*
1380  * Map a LINKTYPE_* code to the corresponding DLT_* code.
1381  * Used to translate link-layer types in savefiles to the
1382  * DLT_* codes to provide to callers of libpcap.
1383  */
1384 int
1385 linktype_to_dlt(int linktype)
1386 {
1387 	/*
1388 	 * All values in the low matching range were handed out before
1389 	 * assigning DLT_* codes became a free-for-all, so they're the
1390 	 * same on all platforms, and are thus used as the LINKTYPE_*
1391 	 * codes in capture files.
1392 	 */
1393 	if (linktype >= LINKTYPE_LOW_MATCHING_MIN &&
1394 	    linktype <= LINKTYPE_LOW_MATCHING_MAX)
1395 		return (linktype);
1396 
1397 #if LINKTYPE_PFSYNC != DLT_PFSYNC
1398 	/*
1399 	 * DLT_PFSYNC has a code on several platforms that's in the
1400 	 * non-matching range, a code on FreeBSD that's in the high
1401 	 * matching range and that's *not* equal to LINKTYPE_PFSYNC,
1402 	 * and has a code on the rmaining platforms that's equal
1403 	 * to LINKTYPE_PFSYNC, which is in the high matching range.
1404 	 *
1405 	 * Map LINKTYPE_PFSYNC to whatever DLT_PFSYNC is on this
1406 	 * platform, if the two aren't equal.
1407 	 */
1408 	if (linktype == LINKTYPE_PFSYNC)
1409 		return (DLT_PFSYNC);
1410 #endif
1411 
1412 	/*
1413 	 * DLT_PKTAP is defined as DLT_USER2 - which is in the high
1414 	 * matching range - on Darwin because Apple used DLT_USER2
1415 	 * on systems that users ran, not just as an internal thing.
1416 	 *
1417 	 * We map LINKTYPE_PKTAP to the platform's DLT_PKTAP for
1418 	 * the benefit of software that's expecting DLT_PKTAP
1419 	 * (even if that's DLT_USER2) for an Apple PKTAP capture.
1420 	 *
1421 	 * (Yes, this is an annoyance if you want to read a
1422 	 * LINKTYPE_USER2 packet as something other than DLT_PKTAP
1423 	 * on a Darwin-based OS, as, on that OS, DLT_PKTAP and DLT_USER2
1424 	 * are the same.  Feel free to complain to Apple about this.)
1425 	 */
1426 #if LINKTYPE_PKTAP != DLT_PKTAP
1427 	if (linktype == LINKTYPE_PKTAP)
1428 		return (DLT_PKTAP);
1429 #endif
1430 
1431 	/*
1432 	 * These DLT_* codes have different values on different
1433 	 * platforms, so we assigned them LINKTYPE_* codes just
1434 	 * below the lower bound of the high matchig range;
1435 	 * those values should never be equal to any DLT_*
1436 	 * code, so that should avoid collisions.
1437 	 *
1438 	 * That way, for example, "raw IP" packets will have
1439 	 * LINKTYPE_RAW as the code in all savefiles for
1440 	 * which the code that writes them maps to that
1441 	 * value, regardless of the platform on which they
1442 	 * were written, so they should be readable on all
1443 	 * platforms without having to determine on which
1444 	 * platform they were written.
1445 	 *
1446 	 * We map the LINKTYPE_* codes to the corresponding
1447 	 * DLT_* code on this platform.
1448 	 */
1449 	if (linktype == LINKTYPE_ATM_RFC1483)
1450 		return (DLT_ATM_RFC1483);
1451 	if (linktype == LINKTYPE_RAW)
1452 		return (DLT_RAW);
1453 	if (linktype == LINKTYPE_SLIP_BSDOS)
1454 		return (DLT_SLIP_BSDOS);
1455 	if (linktype == LINKTYPE_PPP_BSDOS)
1456 		return (DLT_PPP_BSDOS);
1457 
1458 	/*
1459 	 * These DLT_* codes were originally defined on some platform,
1460 	 * and weren't defined on other platforms.
1461 	 *
1462 	 * At least some of them have values, on at least one platform,
1463 	 * that collide with other DLT_* codes on other platforms, e.g.
1464 	 * DLT_LOOP, so we don't just define them, on all platforms,
1465 	 * as having the same value as on the original platform.
1466 	 *
1467 	 * Therefore, we assigned new LINKTYPE_* codes to them, and,
1468 	 * on the platforms where they weren't originally defined,
1469 	 * define the DLT_* codes to have the same value as the
1470 	 * corresponding LINKTYPE_* codes.
1471 	 *
1472 	 * This means that, for capture files with the original
1473 	 * platform's DLT_* code rather than the LINKTYPE_* code
1474 	 * as a link-layer type, we will recognize those types
1475 	 * on that platform, but not on other platforms.
1476 	 *
1477 	 * We map the LINKTYPE_* codes to the corresponding
1478 	 * DLT_* code on platforms where the two codes differ..
1479 	 */
1480 #ifdef DLT_FR
1481 	/* BSD/OS Frame Relay */
1482 	if (linktype == LINKTYPE_FRELAY)
1483 		return (DLT_FR);
1484 #endif
1485 #if LINKTYPE_NETBSD_HDLC != DLT_HDLC
1486 	/* NetBSD HDLC */
1487 	if (linktype == LINKTYPE_NETBSD_HDLC)
1488 		return (DLT_HDLC);
1489 #endif
1490 #if LINKTYPE_C_HDLC != DLT_C_HDLC
1491 	/* BSD/OS Cisco HDLC */
1492 	if (linktype == LINKTYPE_C_HDLC)
1493 		return (DLT_C_HDLC);
1494 #endif
1495 #if LINKTYPE_LOOP != DLT_LOOP
1496 	/* OpenBSD DLT_LOOP */
1497 	if (linktype == LINKTYPE_LOOP)
1498 		return (DLT_LOOP);
1499 #endif
1500 #if LINKTYPE_ENC != DLT_ENC
1501 	/* OpenBSD DLT_ENC */
1502 	if (linktype == LINKTYPE_ENC)
1503 		return (DLT_ENC);
1504 #endif
1505 
1506 	/*
1507 	 * These DLT_* codes are not on all platforms, but, so far,
1508 	 * there don't appear to be any platforms that define
1509 	 * other codes with those values; we map them to
1510 	 * different LINKTYPE_* values anyway, just in case.
1511 	 *
1512 	 * LINKTYPE_ATM_CLIP is a special case.  DLT_ATM_CLIP is
1513 	 * not on all platforms, but, so far, there don't appear
1514 	 * to be any platforms that define it as anything other
1515 	 * than 19; we define LINKTYPE_ATM_CLIP as something
1516 	 * other than 19, just in case.  That value is in the
1517 	 * high matching range, so we have to check for it.
1518 	 */
1519 	/* Linux ATM Classical IP */
1520 	if (linktype == LINKTYPE_ATM_CLIP)
1521 		return (DLT_ATM_CLIP);
1522 
1523 	/*
1524 	 * For all other values, return the linktype code as the
1525 	 * DLT_* code.
1526 	 *
1527 	 * If the code is in the high matching range, the
1528 	 * DLT_* code is the same as the LINKTYPE_* code.
1529 	 *
1530 	 * If the code is greater than the maximum value in
1531 	 * the high matching range, it may be a value from
1532 	 * a newer version of libpcap; we provide it in case
1533 	 * the program' capable of handling it.
1534 	 *
1535 	 * If the code is less than the minimum value in the
1536 	 * high matching range, it might be from a capture
1537 	 * written by code that doesn't map non-matching range
1538 	 * DLT_* codes to the appropriate LINKTYPE_* code, so
1539 	 * we'll just pass it through, so that *if it was written
1540 	 * on this platform* it will be interpreted correctly.
1541 	 * (We don't know whether it was written on this platform,
1542 	 * but at least this way there's *some* chance that it
1543 	 * can be read.)
1544 	 */
1545 	return linktype;
1546 }
1547 
1548 /*
1549  * Return the maximum snapshot length for a given DLT_ value.
1550  *
1551  * For most link-layer types, we use MAXIMUM_SNAPLEN.
1552  *
1553  * For DLT_DBUS, the maximum is 128MiB, as per
1554  *
1555  *    https://dbus.freedesktop.org/doc/dbus-specification.html#message-protocol-messages
1556  *
1557  * For DLT_EBHSCR, the maximum is 8MiB, as per
1558  *
1559  *    https://www.elektrobit.com/ebhscr
1560  *
1561  * For DLT_USBPCAP, the maximum is 1MiB, as per
1562  *
1563  *    https://bugs.wireshark.org/bugzilla/show_bug.cgi?id=15985
1564  */
1565 u_int
1566 max_snaplen_for_dlt(int dlt)
1567 {
1568 	switch (dlt) {
1569 
1570 	case DLT_DBUS:
1571 		return 128*1024*1024;
1572 
1573 	case DLT_EBHSCR:
1574 		return 8*1024*1024;
1575 
1576 	case DLT_USBPCAP:
1577 		return 1024*1024;
1578 
1579 	default:
1580 		return MAXIMUM_SNAPLEN;
1581 	}
1582 }
1583