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 * @(#)bpf.h 7.1 (Berkeley) 5/7/91 39 */ 40 41 /* 42 * This is libpcap's cut-down version of bpf.h; it includes only 43 * the stuff needed for the code generator and the userland BPF 44 * interpreter, and the libpcap APIs for setting filters, etc.. 45 * 46 * "pcap-bpf.c" will include the native OS version, as it deals with 47 * the OS's BPF implementation. 48 * 49 * At least two programs found by Google Code Search explicitly includes 50 * <pcap/bpf.h> (even though <pcap.h>/<pcap/pcap.h> includes it for you), 51 * so moving that stuff to <pcap/pcap.h> would break the build for some 52 * programs. 53 */ 54 55 /* 56 * If we've already included <net/bpf.h>, don't re-define this stuff. 57 * We assume BSD-style multiple-include protection in <net/bpf.h>, 58 * which is true of all but the oldest versions of FreeBSD and NetBSD, 59 * or Tru64 UNIX-style multiple-include protection (or, at least, 60 * Tru64 UNIX 5.x-style; I don't have earlier versions available to check), 61 * or AIX-style multiple-include protection (or, at least, AIX 5.x-style; 62 * I don't have earlier versions available to check), or QNX-style 63 * multiple-include protection (as per GitHub pull request #394). 64 * 65 * We do not check for BPF_MAJOR_VERSION, as that's defined by 66 * <linux/filter.h>, which is directly or indirectly included in some 67 * programs that also include pcap.h, and <linux/filter.h> doesn't 68 * define stuff we need. 69 * 70 * This also provides our own multiple-include protection. 71 */ 72 #if !defined(_NET_BPF_H_) && !defined(_NET_BPF_H_INCLUDED) && !defined(_BPF_H_) && !defined(_H_BPF) && !defined(lib_pcap_bpf_h) 73 #define lib_pcap_bpf_h 74 75 #include <pcap/export-defs.h> 76 77 #ifdef __cplusplus 78 extern "C" { 79 #endif 80 81 /* BSD style release date */ 82 #define BPF_RELEASE 199606 83 84 #ifdef MSDOS /* must be 32-bit */ 85 typedef long bpf_int32; 86 typedef unsigned long bpf_u_int32; 87 #else 88 typedef int bpf_int32; 89 typedef u_int bpf_u_int32; 90 #endif 91 92 /* 93 * Alignment macros. BPF_WORDALIGN rounds up to the next 94 * even multiple of BPF_ALIGNMENT. 95 * 96 * Tcpdump's print-pflog.c uses this, so we define it here. 97 */ 98 #ifndef __NetBSD__ 99 #define BPF_ALIGNMENT sizeof(bpf_int32) 100 #else 101 #define BPF_ALIGNMENT sizeof(long) 102 #endif 103 #define BPF_WORDALIGN(x) (((x)+(BPF_ALIGNMENT-1))&~(BPF_ALIGNMENT-1)) 104 105 /* 106 * Structure for "pcap_compile()", "pcap_setfilter()", etc.. 107 */ 108 struct bpf_program { 109 u_int bf_len; 110 struct bpf_insn *bf_insns; 111 }; 112 113 #include <pcap/dlt.h> 114 115 /* 116 * The instruction encodings. 117 * 118 * Please inform tcpdump-workers (at) lists.tcpdump.org if you use any 119 * of the reserved values, so that we can note that they're used 120 * (and perhaps implement it in the reference BPF implementation 121 * and encourage its implementation elsewhere). 122 */ 123 124 /* 125 * The upper 8 bits of the opcode aren't used. BSD/OS used 0x8000. 126 */ 127 128 /* instruction classes */ 129 #define BPF_CLASS(code) ((code) & 0x07) 130 #define BPF_LD 0x00 131 #define BPF_LDX 0x01 132 #define BPF_ST 0x02 133 #define BPF_STX 0x03 134 #define BPF_ALU 0x04 135 #define BPF_JMP 0x05 136 #define BPF_RET 0x06 137 #define BPF_MISC 0x07 138 139 /* ld/ldx fields */ 140 #define BPF_SIZE(code) ((code) & 0x18) 141 #define BPF_W 0x00 142 #define BPF_H 0x08 143 #define BPF_B 0x10 144 /* 0x18 reserved; used by BSD/OS */ 145 #define BPF_MODE(code) ((code) & 0xe0) 146 #define BPF_IMM 0x00 147 #define BPF_ABS 0x20 148 #define BPF_IND 0x40 149 #define BPF_MEM 0x60 150 #define BPF_LEN 0x80 151 #define BPF_MSH 0xa0 152 /* 0xc0 reserved; used by BSD/OS */ 153 /* 0xe0 reserved; used by BSD/OS */ 154 155 /* alu/jmp fields */ 156 #define BPF_OP(code) ((code) & 0xf0) 157 #define BPF_ADD 0x00 158 #define BPF_SUB 0x10 159 #define BPF_MUL 0x20 160 #define BPF_DIV 0x30 161 #define BPF_OR 0x40 162 #define BPF_AND 0x50 163 #define BPF_LSH 0x60 164 #define BPF_RSH 0x70 165 #define BPF_NEG 0x80 166 #define BPF_MOD 0x90 167 #define BPF_XOR 0xa0 168 /* 0xb0 reserved */ 169 /* 0xc0 reserved */ 170 /* 0xd0 reserved */ 171 /* 0xe0 reserved */ 172 /* 0xf0 reserved */ 173 174 #define BPF_JA 0x00 175 #define BPF_JEQ 0x10 176 #define BPF_JGT 0x20 177 #define BPF_JGE 0x30 178 #define BPF_JSET 0x40 179 /* 0x50 reserved; used on BSD/OS */ 180 /* 0x60 reserved */ 181 /* 0x70 reserved */ 182 /* 0x80 reserved */ 183 /* 0x90 reserved */ 184 /* 0xa0 reserved */ 185 /* 0xb0 reserved */ 186 /* 0xc0 reserved */ 187 /* 0xd0 reserved */ 188 /* 0xe0 reserved */ 189 /* 0xf0 reserved */ 190 #define BPF_SRC(code) ((code) & 0x08) 191 #define BPF_K 0x00 192 #define BPF_X 0x08 193 194 /* ret - BPF_K and BPF_X also apply */ 195 #define BPF_RVAL(code) ((code) & 0x18) 196 #define BPF_A 0x10 197 /* 0x18 reserved */ 198 199 /* misc */ 200 #define BPF_MISCOP(code) ((code) & 0xf8) 201 #define BPF_TAX 0x00 202 /* 0x08 reserved */ 203 /* 0x10 reserved */ 204 /* 0x18 reserved */ 205 /* #define BPF_COP 0x20 NetBSD "coprocessor" extensions */ 206 /* 0x28 reserved */ 207 /* 0x30 reserved */ 208 /* 0x38 reserved */ 209 /* #define BPF_COPX 0x40 NetBSD "coprocessor" extensions */ 210 /* also used on BSD/OS */ 211 /* 0x48 reserved */ 212 /* 0x50 reserved */ 213 /* 0x58 reserved */ 214 /* 0x60 reserved */ 215 /* 0x68 reserved */ 216 /* 0x70 reserved */ 217 /* 0x78 reserved */ 218 #define BPF_TXA 0x80 219 /* 0x88 reserved */ 220 /* 0x90 reserved */ 221 /* 0x98 reserved */ 222 /* 0xa0 reserved */ 223 /* 0xa8 reserved */ 224 /* 0xb0 reserved */ 225 /* 0xb8 reserved */ 226 /* 0xc0 reserved; used on BSD/OS */ 227 /* 0xc8 reserved */ 228 /* 0xd0 reserved */ 229 /* 0xd8 reserved */ 230 /* 0xe0 reserved */ 231 /* 0xe8 reserved */ 232 /* 0xf0 reserved */ 233 /* 0xf8 reserved */ 234 235 /* 236 * The instruction data structure. 237 */ 238 struct bpf_insn { 239 u_short code; 240 u_char jt; 241 u_char jf; 242 bpf_u_int32 k; 243 }; 244 245 /* 246 * Auxiliary data, for use when interpreting a filter intended for the 247 * Linux kernel when the kernel rejects the filter (requiring us to 248 * run it in userland). It contains VLAN tag information. 249 */ 250 struct bpf_aux_data { 251 u_short vlan_tag_present; 252 u_short vlan_tag; 253 }; 254 255 /* 256 * Macros for insn array initializers. 257 */ 258 #define BPF_STMT(code, k) { (u_short)(code), 0, 0, k } 259 #define BPF_JUMP(code, k, jt, jf) { (u_short)(code), jt, jf, k } 260 261 #if __STDC__ || defined(__cplusplus) 262 PCAP_API int bpf_validate(const struct bpf_insn *, int); 263 PCAP_API u_int bpf_filter(const struct bpf_insn *, const u_char *, u_int, u_int); 264 extern u_int bpf_filter_with_aux_data(const struct bpf_insn *, const u_char *, u_int, u_int, const struct bpf_aux_data *); 265 #else 266 PCAP_API int bpf_validate(); 267 PCAP_API u_int bpf_filter(); 268 extern u_int bpf_filter_with_aux_data(); 269 #endif 270 271 /* 272 * Number of scratch memory words (for BPF_LD|BPF_MEM and BPF_ST). 273 */ 274 #define BPF_MEMWORDS 16 275 276 #ifdef __cplusplus 277 } 278 #endif 279 280 #endif /* !defined(_NET_BPF_H_) && !defined(_BPF_H_) && !defined(_H_BPF) && !defined(lib_pcap_bpf_h) */ 281
