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 * @(#) $Header: /tcpdump/master/tcpdump/sll.h,v 1.7 2002/12/11 07:14:11 guy Exp $ (LBL) 39 */ 40 41 /* 42 * For captures on Linux cooked sockets, we construct a fake header 43 * that includes: 44 * 45 * a 2-byte "packet type" which is one of: 46 * 47 * LINUX_SLL_HOST packet was sent to us 48 * LINUX_SLL_BROADCAST packet was broadcast 49 * LINUX_SLL_MULTICAST packet was multicast 50 * LINUX_SLL_OTHERHOST packet was sent to somebody else 51 * LINUX_SLL_OUTGOING packet was sent *by* us; 52 * 53 * a 2-byte Ethernet protocol field; 54 * 55 * a 2-byte link-layer type; 56 * 57 * a 2-byte link-layer address length; 58 * 59 * an 8-byte source link-layer address, whose actual length is 60 * specified by the previous value. 61 * 62 * All fields except for the link-layer address are in network byte order. 63 * 64 * DO NOT change the layout of this structure, or change any of the 65 * LINUX_SLL_ values below. If you must change the link-layer header 66 * for a "cooked" Linux capture, introduce a new DLT_ type (ask 67 * "tcpdump-workers@tcpdump.org" for one, so that you don't give it a 68 * value that collides with a value already being used), and use the 69 * new header in captures of that type, so that programs that can 70 * handle DLT_LINUX_SLL captures will continue to handle them correctly 71 * without any change, and so that capture files with different headers 72 * can be told apart and programs that read them can dissect the 73 * packets in them. 74 * 75 * This structure, and the #defines below, must be the same in the 76 * libpcap and tcpdump versions of "sll.h". 77 */ 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 85 struct sll_header { 86 u_int16_t sll_pkttype; /* packet type */ 87 u_int16_t sll_hatype; /* link-layer address type */ 88 u_int16_t sll_halen; /* link-layer address length */ 89 u_int8_t sll_addr[SLL_ADDRLEN]; /* link-layer address */ 90 u_int16_t sll_protocol; /* protocol */ 91 }; 92 93 /* 94 * The LINUX_SLL_ values for "sll_pkttype"; these correspond to the 95 * PACKET_ values on Linux, but are defined here so that they're 96 * available even on systems other than Linux, and so that they 97 * don't change even if the PACKET_ values change. 98 */ 99 #define LINUX_SLL_HOST 0 100 #define LINUX_SLL_BROADCAST 1 101 #define LINUX_SLL_MULTICAST 2 102 #define LINUX_SLL_OTHERHOST 3 103 #define LINUX_SLL_OUTGOING 4 104 105 /* 106 * The LINUX_SLL_ values for "sll_protocol"; these correspond to the 107 * ETH_P_ values on Linux, but are defined here so that they're 108 * available even on systems other than Linux. We assume, for now, 109 * that the ETH_P_ values won't change in Linux; if they do, then: 110 * 111 * if we don't translate them in "pcap-linux.c", capture files 112 * won't necessarily be readable if captured on a system that 113 * defines ETH_P_ values that don't match these values; 114 * 115 * if we do translate them in "pcap-linux.c", that makes life 116 * unpleasant for the BPF code generator, as the values you test 117 * for in the kernel aren't the values that you test for when 118 * reading a capture file, so the fixup code run on BPF programs 119 * handed to the kernel ends up having to do more work. 120 * 121 * Add other values here as necessary, for handling packet types that 122 * might show up on non-Ethernet, non-802.x networks. (Not all the ones 123 * in the Linux "if_ether.h" will, I suspect, actually show up in 124 * captures.) 125 */ 126 #define LINUX_SLL_P_802_3 0x0001 /* Novell 802.3 frames without 802.2 LLC header */ 127 #define LINUX_SLL_P_802_2 0x0004 /* 802.2 frames (not D/I/X Ethernet) */ 128