FreeBSD/Linux Kernel Cross Reference
sys/device/bpf.h
1 /*
2 * Mach Operating System
3 * Copyright (c) 1993 Carnegie Mellon University
4 * All Rights Reserved.
5 *
6 * Permission to use, copy, modify and distribute this software and its
7 * documentation is hereby granted, provided that both the copyright
8 * notice and this permission notice appear in all copies of the
9 * software, derivative works or modified versions, and any portions
10 * thereof, and that both notices appear in supporting documentation.
11 *
12 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
13 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
14 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
15 *
16 * Carnegie Mellon requests users of this software to return to
17 *
18 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
19 * School of Computer Science
20 * Carnegie Mellon University
21 * Pittsburgh PA 15213-3890
22 *
23 * any improvements or extensions that they make and grant Carnegie Mellon
24 * the rights to redistribute these changes.
25 */
26 /*
27 * HISTORY
28 * $Log: bpf.h,v $
29 * Revision 2.3 93/11/17 16:27:38 dbg
30 * Changed 'long' to 'int' for 64-bit cleanup.
31 * (perhaps we should use int32?)
32 * [93/10/26 dbg]
33 *
34 * Revision 2.2 93/08/10 15:11:16 mrt
35 * 93/02/08 11:28 Masanobu Yuhara at Fujitsu Labs.
36 * Added BPF support. Derived from tcpdump-2.2.1/bpf/net/bpf.h.
37 * Add: New BPF instructions and macros:
38 * BPF_MATCH_IMM, BPF_CKMATCH_IMM, BPF_MATCH_DATA, BPF_REG_DATA,
39 * BPF_POSTPONE, NETF_BPF, BPF_BEGIN, BPF_INSN_STMT, BPF_INSN_JUMP.
40 * Add: BPF_DLBASE for accessing a data link level header.
41 * Changed: BPF_RVAL mask value (0x18 -> 0x38)
42 * [93/02/08 11:28:23 yuhara]
43 *
44 */
45
46 /*
47 * Berkeley Packet Filter Definitions from Berkeley
48 */
49
50 /*-
51 * Copyright (c) 1990-1991 The Regents of the University of California.
52 * All rights reserved.
53 *
54 * This code is derived from the Stanford/CMU enet packet filter,
55 * (net/enet.c) distributed as part of 4.3BSD, and code contributed
56 * to Berkeley by Steven McCanne and Van Jacobson both of Lawrence
57 * Berkeley Laboratory.
58 *
59 * Redistribution and use in source and binary forms, with or without
60 * modification, are permitted provided that the following conditions
61 * are met:
62 * 1. Redistributions of source code must retain the above copyright
63 * notice, this list of conditions and the following disclaimer.
64 * 2. Redistributions in binary form must reproduce the above copyright
65 * notice, this list of conditions and the following disclaimer in the
66 * documentation and/or other materials provided with the distribution.
67 * 3. All advertising materials mentioning features or use of this software
68 * must display the following acknowledgement:
69 * This product includes software developed by the University of
70 * California, Berkeley and its contributors.
71 * 4. Neither the name of the University nor the names of its contributors
72 * may be used to endorse or promote products derived from this software
73 * without specific prior written permission.
74 *
75 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
76 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
77 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
78 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
79 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
80 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
81 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
82 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
83 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
84 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
85 * SUCH DAMAGE.
86 *
87 * @(#)bpf.h 7.1 (Berkeley) 5/7/91
88 *
89 * @(#) $Header: bpf.h,v 2.3 93/11/17 16:27:38 dbg Exp $ (LBL)
90 */
91
92 #ifndef _DEVICE_BPF_H_
93 #define _DEVICE_BPF_H_
94
95 #if 0 /* not used in MK now */
96 /*
97 * Alignment macros. BPF_WORDALIGN rounds up to the next
98 * even multiple of BPF_ALIGNMENT.
99 */
100 #define BPF_ALIGNMENT sizeof(int)
101 #define BPF_WORDALIGN(x) (((x)+(BPF_ALIGNMENT-1))&~(BPF_ALIGNMENT-1))
102
103 /*
104 * Struct return by BIOCVERSION. This represents the version number of
105 * the filter language described by the instruction encodings below.
106 * bpf understands a program iff kernel_major == filter_major &&
107 * kernel_minor >= filter_minor, that is, if the value returned by the
108 * running kernel has the same major number and a minor number equal
109 * equal to or less than the filter being downloaded. Otherwise, the
110 * results are undefined, meaning an error may be returned or packets
111 * may be accepted haphazardly.
112 * It has nothing to do with the source code version.
113 */
114 struct bpf_version {
115 u_short bv_major;
116 u_short bv_minor;
117 };
118 /* Current version number. */
119 #define BPF_MAJOR_VERSION 1
120 #define BPF_MINOR_VERSION 1
121
122 /*
123 * Data-link level type codes.
124 * Currently, only DLT_EN10MB and DLT_SLIP are supported.
125 */
126 #define DLT_NULL 0 /* no link-layer encapsulation */
127 #define DLT_EN10MB 1 /* Ethernet (10Mb) */
128 #define DLT_EN3MB 2 /* Experimental Ethernet (3Mb) */
129 #define DLT_AX25 3 /* Amateur Radio AX.25 */
130 #define DLT_PRONET 4 /* Proteon ProNET Token Ring */
131 #define DLT_CHAOS 5 /* Chaos */
132 #define DLT_IEEE802 6 /* IEEE 802 Networks */
133 #define DLT_ARCNET 7 /* ARCNET */
134 #define DLT_SLIP 8 /* Serial Line IP */
135 #define DLT_PPP 9 /* Point-to-point Protocol */
136 #define DLT_FDDI 10 /* FDDI */
137
138 #endif /* 0 */
139
140 /*
141 * The instruction encondings.
142 */
143
144 /* Magic number for the first instruction */
145 #define BPF_BEGIN NETF_BPF
146
147 /* instruction classes */
148 #define BPF_CLASS(code) ((code) & 0x07)
149 #define BPF_LD 0x00
150 #define BPF_LDX 0x01
151 #define BPF_ST 0x02
152 #define BPF_STX 0x03
153 #define BPF_ALU 0x04
154 #define BPF_JMP 0x05
155 #define BPF_RET 0x06
156 #define BPF_MISC 0x07
157
158 /* ld/ldx fields */
159 #define BPF_SIZE(code) ((code) & 0x18)
160 #define BPF_W 0x00
161 #define BPF_H 0x08
162 #define BPF_B 0x10
163 #define BPF_MODE(code) ((code) & 0xe0)
164 #define BPF_IMM 0x00
165 #define BPF_ABS 0x20
166 #define BPF_IND 0x40
167 #define BPF_MEM 0x60
168 #define BPF_LEN 0x80
169 #define BPF_MSH 0xa0
170
171 /* alu/jmp fields */
172 #define BPF_OP(code) ((code) & 0xf0)
173 #define BPF_ADD 0x00
174 #define BPF_SUB 0x10
175 #define BPF_MUL 0x20
176 #define BPF_DIV 0x30
177 #define BPF_OR 0x40
178 #define BPF_AND 0x50
179 #define BPF_LSH 0x60
180 #define BPF_RSH 0x70
181 #define BPF_NEG 0x80
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 #define BPF_CKMATCH_IMM 0x50
188 #define BPF_SRC(code) ((code) & 0x08)
189 #define BPF_K 0x00
190 #define BPF_X 0x08
191
192 /* ret - BPF_K and BPF_X also apply */
193 #define BPF_RVAL(code) ((code) & 0x38)
194 #define BPF_A 0x10
195 #define BPF_MATCH_IMM 0x18
196 #define BPF_MATCH_DATA 0x20
197
198 /* misc */
199 #define BPF_MISCOP(code) ((code) & 0xf8)
200 #define BPF_TAX 0x00
201 #define BPF_TXA 0x80
202 #define BPF_KEY 0x10
203 #define BPF_REG_DATA 0x18
204 #define BPF_POSTPONE 0x20
205
206 /*
207 * The instruction data structure.
208 */
209 struct bpf_insn {
210 unsigned short code;
211 unsigned char jt;
212 unsigned char jf;
213 int k;
214 };
215 typedef struct bpf_insn *bpf_insn_t;
216
217 /*
218 * largest bpf program size
219 */
220 #define NET_MAX_BPF ((NET_MAX_FILTER*sizeof(filter_t))/sizeof(struct bpf_insn))
221
222 /*
223 * Macros for insn array initializers.
224 */
225 #define BPF_STMT(code, k) { (unsigned short)(code), 0, 0, k }
226 #define BPF_JUMP(code, k, jt, jf) { (unsigned short)(code), jt, jf, k }
227 #define BPF_RETMATCH(code, k, nkey) { (unsigned short)(code), nkey, 0, k }
228
229 #define BPF_INSN_STMT(pc, c, n) {\
230 (pc)->code = (c); \
231 (pc)->jt = (pc)->jf = 0; \
232 (pc)->k = (n); \
233 (pc)++; \
234 }
235
236 #define BPF_INSN_JUMP(pc, c, n, jtrue, jfalse) {\
237 (pc)->code = (c); \
238 (pc)->jt = (jtrue); \
239 (pc)->jf = (jfalse); \
240 (pc)->k = (n); \
241 (pc)++; \
242 }
243
244 #define BPF_INSN_RETMATCH(pc, c, n, nkey) {\
245 (pc)->code = (c); \
246 (pc)->jt = (nkey); \
247 (pc)->jf = 0; \
248 (pc)->k = (n); \
249 (pc)++; \
250 }
251
252 /*
253 * Number of scratch memory words (for BPF_LD|BPF_MEM and BPF_ST).
254 */
255 #define BPF_MEMWORDS 16
256
257 /*
258 * Link level header can be accessed by adding BPF_DLBASE to an offset.
259 */
260 #define BPF_DLBASE (1<<30)
261
262 #define BPF_BYTES(n) ((n) * sizeof (struct bpf_insn))
263 #define BPF_BYTES2LEN(n) ((n) / sizeof (struct bpf_insn))
264 #define BPF_INSN_EQ(p,q) ((p)->code == (q)->code && \
265 (p)->jt == (q)->jt && \
266 (p)->jf == (q)->jf && \
267 (p)->k == (q)->k)
268
269 #endif /* _DEVICE_BPF_H_ */
Cache object: 9a57bd8ecec46834af67d18aea078c47
|