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. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#) Header: /tcpdump/master/tcpdump/sll.h,v 1.8 2008-05-30 01:37:41 guy Exp (LBL) 35 */ 36 37/* 38 * For captures on Linux cooked sockets, we construct a fake header 39 * that includes: 40 * 41 * a 2-byte "packet type" which is one of: 42 * 43 * LINUX_SLL_HOST packet was sent to us 44 * LINUX_SLL_BROADCAST packet was broadcast 45 * LINUX_SLL_MULTICAST packet was multicast 46 * LINUX_SLL_OTHERHOST packet was sent to somebody else 47 * LINUX_SLL_OUTGOING packet was sent *by* us; 48 * 49 * a 2-byte Ethernet protocol field; 50 * 51 * a 2-byte link-layer type; 52 * 53 * a 2-byte link-layer address length; 54 * 55 * an 8-byte source link-layer address, whose actual length is 56 * specified by the previous value. 57 * 58 * All fields except for the link-layer address are in network byte order. 59 * 60 * DO NOT change the layout of this structure, or change any of the 61 * LINUX_SLL_ values below. If you must change the link-layer header 62 * for a "cooked" Linux capture, introduce a new DLT_ type (ask 63 * "tcpdump-workers@lists.tcpdump.org" for one, so that you don't give it 64 * a value that collides with a value already being used), and use the 65 * new header in captures of that type, so that programs that can 66 * handle DLT_LINUX_SLL captures will continue to handle them correctly 67 * without any change, and so that capture files with different headers 68 * can be told apart and programs that read them can dissect the 69 * packets in them. 70 * 71 * This structure, and the #defines below, must be the same in the 72 * libpcap and tcpdump versions of "sll.h". 73 */ 74 75/* 76 * A DLT_LINUX_SLL fake link-layer header. 77 */ 78#define SLL_HDR_LEN 16 /* total header length */ 79#define SLL_ADDRLEN 8 /* length of address field */ 80 81struct sll_header { 82 u_int16_t sll_pkttype; /* packet type */ 83 u_int16_t sll_hatype; /* link-layer address type */ 84 u_int16_t sll_halen; /* link-layer address length */ 85 u_int8_t sll_addr[SLL_ADDRLEN]; /* link-layer address */ 86 u_int16_t sll_protocol; /* protocol */ 87}; 88 89/* 90 * The LINUX_SLL_ values for "sll_pkttype"; these correspond to the 91 * PACKET_ values on Linux, but are defined here so that they're 92 * available even on systems other than Linux, and so that they 93 * don't change even if the PACKET_ values change. 94 */ 95#define LINUX_SLL_HOST 0 96#define LINUX_SLL_BROADCAST 1 97#define LINUX_SLL_MULTICAST 2 98#define LINUX_SLL_OTHERHOST 3 99#define LINUX_SLL_OUTGOING 4 100 101/* 102 * The LINUX_SLL_ values for "sll_protocol"; these correspond to the 103 * ETH_P_ values on Linux, but are defined here so that they're 104 * available even on systems other than Linux. We assume, for now, 105 * that the ETH_P_ values won't change in Linux; if they do, then: 106 * 107 * if we don't translate them in "pcap-linux.c", capture files 108 * won't necessarily be readable if captured on a system that 109 * defines ETH_P_ values that don't match these values; 110 * 111 * if we do translate them in "pcap-linux.c", that makes life 112 * unpleasant for the BPF code generator, as the values you test 113 * for in the kernel aren't the values that you test for when 114 * reading a capture file, so the fixup code run on BPF programs 115 * handed to the kernel ends up having to do more work. 116 * 117 * Add other values here as necessary, for handling packet types that 118 * might show up on non-Ethernet, non-802.x networks. (Not all the ones 119 * in the Linux "if_ether.h" will, I suspect, actually show up in 120 * captures.) 121 */ 122#define LINUX_SLL_P_802_3 0x0001 /* Novell 802.3 frames without 802.2 LLC header */ 123#define LINUX_SLL_P_802_2 0x0004 /* 802.2 frames (not D/I/X Ethernet) */ 124