1/*-
2 * Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * This code is derived from the Stanford/CMU enet packet filter,
6 * (net/enet.c) distributed as part of 4.3BSD, and code contributed
7 * to Berkeley by Steven McCanne and Van Jacobson both of Lawrence
8 * Berkeley Laboratory.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 *    must display the following acknowledgement:
20 *      This product includes software developed by the University of
21 *      California, Berkeley and its contributors.
22 * 4. Neither the name of the University nor the names of its contributors
23 *    may be used to endorse or promote products derived from this software
24 *    without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * SUCH DAMAGE.
37 */
38
39/*
40 * For captures on Linux cooked sockets, we construct a fake header
41 * that includes:
42 *
43 *	a 2-byte "packet type" which is one of:
44 *
45 *		LINUX_SLL_HOST		packet was sent to us
46 *		LINUX_SLL_BROADCAST	packet was broadcast
47 *		LINUX_SLL_MULTICAST	packet was multicast
48 *		LINUX_SLL_OTHERHOST	packet was sent to somebody else
49 *		LINUX_SLL_OUTGOING	packet was sent *by* us;
50 *
51 *	a 2-byte Ethernet protocol field;
52 *
53 *	a 2-byte link-layer type;
54 *
55 *	a 2-byte link-layer address length;
56 *
57 *	an 8-byte source link-layer address, whose actual length is
58 *	specified by the previous value.
59 *
60 * All fields except for the link-layer address are in network byte order.
61 *
62 * DO NOT change the layout of this structure, or change any of the
63 * LINUX_SLL_ values below.  If you must change the link-layer header
64 * for a "cooked" Linux capture, introduce a new DLT_ type (ask
65 * "tcpdump-workers@lists.tcpdump.org" for one, so that you don't give it
66 * a value that collides with a value already being used), and use the
67 * new header in captures of that type, so that programs that can
68 * handle DLT_LINUX_SLL captures will continue to handle them correctly
69 * without any change, and so that capture files with different headers
70 * can be told apart and programs that read them can dissect the
71 * packets in them.
72 */
73
74#ifndef lib_pcap_sll_h
75#define lib_pcap_sll_h
76
77#include <pcap/pcap-inttypes.h>
78
79/*
80 * A DLT_LINUX_SLL fake link-layer header.
81 */
82#define SLL_HDR_LEN	16		/* total header length */
83#define SLL_ADDRLEN	8		/* length of address field */
84
85struct sll_header {
86	uint16_t sll_pkttype;		/* packet type */
87	uint16_t sll_hatype;		/* link-layer address type */
88	uint16_t sll_halen;		/* link-layer address length */
89	uint8_t  sll_addr[SLL_ADDRLEN];	/* link-layer address */
90	uint16_t sll_protocol;		/* protocol */
91};
92
93/*
94 * A DLT_LINUX_SLL2 fake link-layer header.
95 */
96#define SLL2_HDR_LEN	20		/* total header length */
97
98struct sll2_header {
99	uint16_t sll2_protocol;			/* protocol */
100	uint16_t sll2_reserved_mbz;		/* reserved - must be zero */
101	uint32_t sll2_if_index;			/* 1-based interface index */
102	uint16_t sll2_hatype;			/* link-layer address type */
103	uint8_t  sll2_pkttype;			/* packet type */
104	uint8_t  sll2_halen;			/* link-layer address length */
105	uint8_t  sll2_addr[SLL_ADDRLEN];	/* link-layer address */
106};
107
108/*
109 * The LINUX_SLL_ values for "sll_pkttype" and LINUX_SLL2_ values for
110 * "sll2_pkttype"; these correspond to the PACKET_ values on Linux,
111 * which are defined by a header under include/uapi in the current
112 * kernel source, and are thus not going to change on Linux.  We
113 * define them here so that they're available even on systems other
114 * than Linux.
115 */
116#define LINUX_SLL_HOST		0
117#define LINUX_SLL_BROADCAST	1
118#define LINUX_SLL_MULTICAST	2
119#define LINUX_SLL_OTHERHOST	3
120#define LINUX_SLL_OUTGOING	4
121
122/*
123 * The LINUX_SLL_ values for "sll_protocol" and LINUX_SLL2_ values for
124 * "sll2_protocol"; these correspond to the ETH_P_ values on Linux, but
125 * are defined here so that they're available even on systems other than
126 * Linux.  We assume, for now, that the ETH_P_ values won't change in
127 * Linux; if they do, then:
128 *
129 *	if we don't translate them in "pcap-linux.c", capture files
130 *	won't necessarily be readable if captured on a system that
131 *	defines ETH_P_ values that don't match these values;
132 *
133 *	if we do translate them in "pcap-linux.c", that makes life
134 *	unpleasant for the BPF code generator, as the values you test
135 *	for in the kernel aren't the values that you test for when
136 *	reading a capture file, so the fixup code run on BPF programs
137 *	handed to the kernel ends up having to do more work.
138 *
139 * Add other values here as necessary, for handling packet types that
140 * might show up on non-Ethernet, non-802.x networks.  (Not all the ones
141 * in the Linux "if_ether.h" will, I suspect, actually show up in
142 * captures.)
143 */
144#define LINUX_SLL_P_802_3	0x0001	/* Novell 802.3 frames without 802.2 LLC header */
145#define LINUX_SLL_P_802_2	0x0004	/* 802.2 frames (not D/I/X Ethernet) */
146#define LINUX_SLL_P_CAN		0x000C	/* CAN frames, with SocketCAN pseudo-headers */
147#define LINUX_SLL_P_CANFD	0x000D	/* CAN FD frames, with SocketCAN pseudo-headers */
148
149#endif
150