1/* $NetBSD: bpf.h,v 1.11 2023/08/17 15:18:13 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. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)bpf.h 7.1 (Berkeley) 5/7/91 37 */ 38#error "This is not used in NetBSD, we use <net/bpf.h>" 39/* 40 * This is libpcap's cut-down version of bpf.h; it includes only 41 * the stuff needed for the code generator and the userland BPF 42 * interpreter, and the libpcap APIs for setting filters, etc.. 43 * 44 * "pcap-bpf.c" will include the native OS version, as it deals with 45 * the OS's BPF implementation. 46 * 47 * At least two programs found by Google Code Search explicitly includes 48 * <pcap/bpf.h> (even though <pcap.h>/<pcap/pcap.h> includes it for you), 49 * so moving that stuff to <pcap/pcap.h> would break the build for some 50 * programs. 51 */ 52 53/* 54 * If we've already included <net/bpf.h>, don't re-define this stuff. 55 * We assume BSD-style multiple-include protection in <net/bpf.h>, 56 * which is true of all but the oldest versions of FreeBSD and NetBSD, 57 * or Tru64 UNIX-style multiple-include protection (or, at least, 58 * Tru64 UNIX 5.x-style; I don't have earlier versions available to check), 59 * or AIX-style multiple-include protection (or, at least, AIX 5.x-style; 60 * I don't have earlier versions available to check), or QNX-style 61 * multiple-include protection (as per GitHub pull request #394). 62 * 63 * We trust that they will define structures and macros and types in 64 * a fashion that's source-compatible and binary-compatible with our 65 * definitions. 66 * 67 * We do not check for BPF_MAJOR_VERSION, as that's defined by 68 * <linux/filter.h>, which is directly or indirectly included in some 69 * programs that also include pcap.h, and <linux/filter.h> doesn't 70 * define stuff we need. We *do* protect against <linux/filter.h> 71 * defining various macros for BPF code itself; <linux/filter.h> says 72 * 73 * Try and keep these values and structures similar to BSD, especially 74 * the BPF code definitions which need to match so you can share filters 75 * 76 * so we trust that it will define them in a fashion that's source-compatible 77 * and binary-compatible with our definitions. 78 * 79 * This also provides our own multiple-include protection. 80 */ 81#if !defined(_NET_BPF_H_) && !defined(_NET_BPF_H_INCLUDED) && !defined(_BPF_H_) && !defined(_H_BPF) && !defined(lib_pcap_bpf_h) 82#define lib_pcap_bpf_h 83 84#include <pcap/funcattrs.h> 85#include <pcap/dlt.h> 86 87#ifdef __cplusplus 88extern "C" { 89#endif 90 91/* BSD style release date */ 92#define BPF_RELEASE 199606 93 94#ifdef MSDOS /* must be 32-bit */ 95typedef long bpf_int32; 96typedef unsigned long bpf_u_int32; 97#else 98typedef int bpf_int32; 99typedef u_int bpf_u_int32; 100#endif 101 102/* 103 * Alignment macros. BPF_WORDALIGN rounds up to the next 104 * even multiple of BPF_ALIGNMENT. 105 * 106 * Tcpdump's print-pflog.c uses this, so we define it here. 107 */ 108#ifndef __NetBSD__ 109#define BPF_ALIGNMENT sizeof(bpf_int32) 110#else 111#define BPF_ALIGNMENT sizeof(long) 112#endif 113#define BPF_WORDALIGN(x) (((x)+(BPF_ALIGNMENT-1))&~(BPF_ALIGNMENT-1)) 114 115/* 116 * Structure for "pcap_compile()", "pcap_setfilter()", etc.. 117 */ 118struct bpf_program { 119 u_int bf_len; 120 struct bpf_insn *bf_insns; 121}; 122 123/* 124 * The instruction encodings. 125 * 126 * Please inform tcpdump-workers@lists.tcpdump.org if you use any 127 * of the reserved values, so that we can note that they're used 128 * (and perhaps implement it in the reference BPF implementation 129 * and encourage its implementation elsewhere). 130 */ 131 132/* 133 * The upper 8 bits of the opcode aren't used. BSD/OS used 0x8000. 134 */ 135 136/* instruction classes */ 137#define BPF_CLASS(code) ((code) & 0x07) 138#define BPF_LD 0x00 139#define BPF_LDX 0x01 140#define BPF_ST 0x02 141#define BPF_STX 0x03 142#define BPF_ALU 0x04 143#define BPF_JMP 0x05 144#define BPF_RET 0x06 145#define BPF_MISC 0x07 146 147/* ld/ldx fields */ 148#define BPF_SIZE(code) ((code) & 0x18) 149#define BPF_W 0x00 150#define BPF_H 0x08 151#define BPF_B 0x10 152/* 0x18 reserved; used by BSD/OS */ 153#define BPF_MODE(code) ((code) & 0xe0) 154#define BPF_IMM 0x00 155#define BPF_ABS 0x20 156#define BPF_IND 0x40 157#define BPF_MEM 0x60 158#define BPF_LEN 0x80 159#define BPF_MSH 0xa0 160/* 0xc0 reserved; used by BSD/OS */ 161/* 0xe0 reserved; used by BSD/OS */ 162 163/* alu/jmp fields */ 164#define BPF_OP(code) ((code) & 0xf0) 165#define BPF_ADD 0x00 166#define BPF_SUB 0x10 167#define BPF_MUL 0x20 168#define BPF_DIV 0x30 169#define BPF_OR 0x40 170#define BPF_AND 0x50 171#define BPF_LSH 0x60 172#define BPF_RSH 0x70 173#define BPF_NEG 0x80 174#define BPF_MOD 0x90 175#define BPF_XOR 0xa0 176/* 0xb0 reserved */ 177/* 0xc0 reserved */ 178/* 0xd0 reserved */ 179/* 0xe0 reserved */ 180/* 0xf0 reserved */ 181 182#define BPF_JA 0x00 183#define BPF_JEQ 0x10 184#define BPF_JGT 0x20 185#define BPF_JGE 0x30 186#define BPF_JSET 0x40 187/* 0x50 reserved; used on BSD/OS */ 188/* 0x60 reserved */ 189/* 0x70 reserved */ 190/* 0x80 reserved */ 191/* 0x90 reserved */ 192/* 0xa0 reserved */ 193/* 0xb0 reserved */ 194/* 0xc0 reserved */ 195/* 0xd0 reserved */ 196/* 0xe0 reserved */ 197/* 0xf0 reserved */ 198#define BPF_SRC(code) ((code) & 0x08) 199#define BPF_K 0x00 200#define BPF_X 0x08 201 202/* ret - BPF_K and BPF_X also apply */ 203#define BPF_RVAL(code) ((code) & 0x18) 204#define BPF_A 0x10 205/* 0x18 reserved */ 206 207/* misc */ 208#define BPF_MISCOP(code) ((code) & 0xf8) 209#define BPF_TAX 0x00 210/* 0x08 reserved */ 211/* 0x10 reserved */ 212/* 0x18 reserved */ 213/* #define BPF_COP 0x20 NetBSD "coprocessor" extensions */ 214/* 0x28 reserved */ 215/* 0x30 reserved */ 216/* 0x38 reserved */ 217/* #define BPF_COPX 0x40 NetBSD "coprocessor" extensions */ 218/* also used on BSD/OS */ 219/* 0x48 reserved */ 220/* 0x50 reserved */ 221/* 0x58 reserved */ 222/* 0x60 reserved */ 223/* 0x68 reserved */ 224/* 0x70 reserved */ 225/* 0x78 reserved */ 226#define BPF_TXA 0x80 227/* 0x88 reserved */ 228/* 0x90 reserved */ 229/* 0x98 reserved */ 230/* 0xa0 reserved */ 231/* 0xa8 reserved */ 232/* 0xb0 reserved */ 233/* 0xb8 reserved */ 234/* 0xc0 reserved; used on BSD/OS */ 235/* 0xc8 reserved */ 236/* 0xd0 reserved */ 237/* 0xd8 reserved */ 238/* 0xe0 reserved */ 239/* 0xe8 reserved */ 240/* 0xf0 reserved */ 241/* 0xf8 reserved */ 242 243/* 244 * The instruction data structure. 245 */ 246struct bpf_insn { 247 u_short code; 248 u_char jt; 249 u_char jf; 250 bpf_u_int32 k; 251}; 252 253/* 254 * Macros for insn array initializers. 255 * 256 * In case somebody's included <linux/filter.h>, or something else that 257 * gives the kernel's definitions of BPF statements, get rid of its 258 * definitions, so we can supply ours instead. If some kernel's 259 * definitions aren't *binary-compatible* with what BPF has had 260 * since it first sprung from the brows of Van Jacobson and Steve 261 * McCanne, that kernel should be fixed. 262 */ 263#ifdef BPF_STMT 264#undef BPF_STMT 265#endif 266#define BPF_STMT(code, k) { (u_short)(code), 0, 0, k } 267#ifdef BPF_JUMP 268#undef BPF_JUMP 269#endif 270#define BPF_JUMP(code, k, jt, jf) { (u_short)(code), jt, jf, k } 271 272PCAP_AVAILABLE_0_4 273PCAP_API u_int bpf_filter(const struct bpf_insn *, const u_char *, u_int, u_int); 274 275PCAP_AVAILABLE_0_6 276PCAP_API int bpf_validate(const struct bpf_insn *f, int len); 277 278PCAP_AVAILABLE_0_4 279PCAP_API char *bpf_image(const struct bpf_insn *, int); 280 281PCAP_AVAILABLE_0_6 282PCAP_API void bpf_dump(const struct bpf_program *, int); 283 284/* 285 * Number of scratch memory words (for BPF_LD|BPF_MEM and BPF_ST). 286 */ 287#define BPF_MEMWORDS 16 288 289#ifdef __cplusplus 290} 291#endif 292 293#endif /* !defined(_NET_BPF_H_) && !defined(_BPF_H_) && !defined(_H_BPF) && !defined(lib_pcap_bpf_h) */ 294