1 /* $NetBSD: sll.h,v 1.6 2024/09/02 15:33:39 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from the Stanford/CMU enet packet filter, 8 * (net/enet.c) distributed as part of 4.3BSD, and code contributed 9 * to Berkeley by Steven McCanne and Van Jacobson both of Lawrence 10 * Berkeley Laboratory. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. All advertising materials mentioning features or use of this software 21 * must display the following acknowledgement: 22 * This product includes software developed by the University of 23 * California, Berkeley and its contributors. 24 * 4. Neither the name of the University nor the names of its contributors 25 * may be used to endorse or promote products derived from this software 26 * without specific prior written permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 38 * SUCH DAMAGE. 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@lists.tcpdump.org" for one, so that you don't give it 68 * a 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 76 #ifndef lib_pcap_sll_h 77 #define lib_pcap_sll_h 78 79 #include <pcap/pcap-inttypes.h> 80 81 /* 82 * A DLT_LINUX_SLL fake link-layer header. 83 */ 84 #define SLL_HDR_LEN 16 /* total header length */ 85 #define SLL_ADDRLEN 8 /* length of address field */ 86 87 struct sll_header { 88 uint16_t sll_pkttype; /* packet type */ 89 uint16_t sll_hatype; /* link-layer address type */ 90 uint16_t sll_halen; /* link-layer address length */ 91 uint8_t sll_addr[SLL_ADDRLEN]; /* link-layer address */ 92 uint16_t sll_protocol; /* protocol */ 93 }; 94 95 /* 96 * A DLT_LINUX_SLL2 fake link-layer header. 97 */ 98 #define SLL2_HDR_LEN 20 /* total header length */ 99 100 struct sll2_header { 101 uint16_t sll2_protocol; /* protocol */ 102 uint16_t sll2_reserved_mbz; /* reserved - must be zero */ 103 uint32_t sll2_if_index; /* 1-based interface index */ 104 uint16_t sll2_hatype; /* link-layer address type */ 105 uint8_t sll2_pkttype; /* packet type */ 106 uint8_t sll2_halen; /* link-layer address length */ 107 uint8_t sll2_addr[SLL_ADDRLEN]; /* link-layer address */ 108 }; 109 110 /* 111 * The LINUX_SLL_ values for "sll_pkttype" and LINUX_SLL2_ values for 112 * "sll2_pkttype"; these correspond to the PACKET_ values on Linux, 113 * which are defined by a header under include/uapi in the current 114 * kernel source, and are thus not going to change on Linux. We 115 * define them here so that they're available even on systems other 116 * than Linux. 117 */ 118 #define LINUX_SLL_HOST 0 119 #define LINUX_SLL_BROADCAST 1 120 #define LINUX_SLL_MULTICAST 2 121 #define LINUX_SLL_OTHERHOST 3 122 #define LINUX_SLL_OUTGOING 4 123 124 /* 125 * The LINUX_SLL_ values for "sll_protocol" and LINUX_SLL2_ values for 126 * "sll2_protocol"; these correspond to the ETH_P_ values on Linux, but 127 * are defined here so that they're available even on systems other than 128 * Linux. We assume, for now, that the ETH_P_ values won't change in 129 * Linux; if they do, then: 130 * 131 * if we don't translate them in "pcap-linux.c", capture files 132 * won't necessarily be readable if captured on a system that 133 * defines ETH_P_ values that don't match these values; 134 * 135 * if we do translate them in "pcap-linux.c", that makes life 136 * unpleasant for the BPF code generator, as the values you test 137 * for in the kernel aren't the values that you test for when 138 * reading a capture file, so the fixup code run on BPF programs 139 * handed to the kernel ends up having to do more work. 140 * 141 * Add other values here as necessary, for handling packet types that 142 * might show up on non-Ethernet, non-802.x networks. (Not all the ones 143 * in the Linux "if_ether.h" will, I suspect, actually show up in 144 * captures.) 145 */ 146 #define LINUX_SLL_P_802_3 0x0001 /* Novell 802.3 frames without 802.2 LLC header */ 147 #define LINUX_SLL_P_802_2 0x0004 /* 802.2 frames (not D/I/X Ethernet) */ 148 #define LINUX_SLL_P_CAN 0x000C /* CAN frames, with SocketCAN pseudo-headers */ 149 #define LINUX_SLL_P_CANFD 0x000D /* CAN FD frames, with SocketCAN pseudo-headers */ 150 #define LINUX_SLL_P_CANXL 0x000E /* CAN XL frames, with SocketCAN pseudo-headers */ 151 152 #endif 153