1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
|
/*
* Mach Operating System
* Copyright (c) 1993 Carnegie Mellon University
* All Rights Reserved.
*
* Permission to use, copy, modify and distribute this software and its
* documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie Mellon
* the rights to redistribute these changes.
*/
/*
* Berkeley Packet Filter Definitions from Berkeley
*/
/*-
* Copyright (c) 1990-1991 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from the Stanford/CMU enet packet filter,
* (net/enet.c) distributed as part of 4.3BSD, and code contributed
* to Berkeley by Steven McCanne and Van Jacobson both of Lawrence
* Berkeley Laboratory.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)bpf.h 7.1 (Berkeley) 5/7/91
*
*/
#ifndef _DEVICE_BPF_H_
#define _DEVICE_BPF_H_
#include <sys/types.h> /* u_short */
/*
* Alignment macros. BPF_WORDALIGN rounds up to the next
* even multiple of BPF_ALIGNMENT.
*/
#define BPF_ALIGNMENT sizeof(int)
#define BPF_WORDALIGN(x) (((x)+(BPF_ALIGNMENT-1))&~(BPF_ALIGNMENT-1))
/*
* Struct return by BIOCVERSION. This represents the version number of
* the filter language described by the instruction encodings below.
* bpf understands a program iff kernel_major == filter_major &&
* kernel_minor >= filter_minor, that is, if the value returned by the
* running kernel has the same major number and a minor number equal
* equal to or less than the filter being downloaded. Otherwise, the
* results are undefined, meaning an error may be returned or packets
* may be accepted haphazardly.
* It has nothing to do with the source code version.
*/
struct bpf_version {
u_short bv_major;
u_short bv_minor;
};
/* Current version number. */
#define BPF_MAJOR_VERSION 1
#define BPF_MINOR_VERSION 1
/*
* Data-link level type codes.
* Currently, only DLT_EN10MB and DLT_SLIP are supported.
*/
#define DLT_NULL 0 /* no link-layer encapsulation */
#define DLT_EN10MB 1 /* Ethernet (10Mb) */
#define DLT_EN3MB 2 /* Experimental Ethernet (3Mb) */
#define DLT_AX25 3 /* Amateur Radio AX.25 */
#define DLT_PRONET 4 /* Proteon ProNET Token Ring */
#define DLT_CHAOS 5 /* Chaos */
#define DLT_IEEE802 6 /* IEEE 802 Networks */
#define DLT_ARCNET 7 /* ARCNET */
#define DLT_SLIP 8 /* Serial Line IP */
#define DLT_PPP 9 /* Point-to-point Protocol */
#define DLT_FDDI 10 /* FDDI */
/*
* The instruction encondings.
*/
/* Magic number and flags for the first instruction */
#define BPF_BEGIN NETF_BPF
#define BPF_IN NETF_IN
#define BPF_OUT NETF_OUT
/* instruction classes */
#define BPF_CLASS(code) ((code) & 0x07)
#define BPF_LD 0x00
#define BPF_LDX 0x01
#define BPF_ST 0x02
#define BPF_STX 0x03
#define BPF_ALU 0x04
#define BPF_JMP 0x05
#define BPF_RET 0x06
#define BPF_MISC 0x07
/* ld/ldx fields */
#define BPF_SIZE(code) ((code) & 0x18)
#define BPF_W 0x00
#define BPF_H 0x08
#define BPF_B 0x10
#define BPF_MODE(code) ((code) & 0xe0)
#define BPF_IMM 0x00
#define BPF_ABS 0x20
#define BPF_IND 0x40
#define BPF_MEM 0x60
#define BPF_LEN 0x80
#define BPF_MSH 0xa0
/* alu/jmp fields */
#define BPF_OP(code) ((code) & 0xf0)
#define BPF_ADD 0x00
#define BPF_SUB 0x10
#define BPF_MUL 0x20
#define BPF_DIV 0x30
#define BPF_OR 0x40
#define BPF_AND 0x50
#define BPF_LSH 0x60
#define BPF_RSH 0x70
#define BPF_NEG 0x80
#define BPF_JA 0x00
#define BPF_JEQ 0x10
#define BPF_JGT 0x20
#define BPF_JGE 0x30
#define BPF_JSET 0x40
#define BPF_CKMATCH_IMM 0x50
#define BPF_SRC(code) ((code) & 0x08)
#define BPF_K 0x00
#define BPF_X 0x08
/* ret - BPF_K and BPF_X also apply */
#define BPF_RVAL(code) ((code) & 0x38)
#define BPF_A 0x10
#define BPF_MATCH_IMM 0x18
#define BPF_MATCH_DATA 0x20
/* misc */
#define BPF_MISCOP(code) ((code) & 0xf8)
#define BPF_TAX 0x00
#define BPF_TXA 0x80
#define BPF_KEY 0x10
#define BPF_REG_DATA 0x18
#define BPF_POSTPONE 0x20
/*
* The instruction data structure.
*/
struct bpf_insn {
unsigned short code;
unsigned char jt;
unsigned char jf;
int k;
};
typedef struct bpf_insn *bpf_insn_t;
/*
* largest bpf program size
*/
#define NET_MAX_BPF ((NET_MAX_FILTER*sizeof(filter_t))/sizeof(struct bpf_insn))
/*
* Macros for insn array initializers.
*/
#define BPF_STMT(code, k) { (unsigned short)(code), 0, 0, k }
#define BPF_JUMP(code, k, jt, jf) { (unsigned short)(code), jt, jf, k }
#define BPF_RETMATCH(code, k, nkey) { (unsigned short)(code), nkey, 0, k }
#define BPF_INSN_STMT(pc, c, n) {\
(pc)->code = (c); \
(pc)->jt = (pc)->jf = 0; \
(pc)->k = (n); \
(pc)++; \
}
#define BPF_INSN_JUMP(pc, c, n, jtrue, jfalse) {\
(pc)->code = (c); \
(pc)->jt = (jtrue); \
(pc)->jf = (jfalse); \
(pc)->k = (n); \
(pc)++; \
}
#define BPF_INSN_RETMATCH(pc, c, n, nkey) {\
(pc)->code = (c); \
(pc)->jt = (nkey); \
(pc)->jf = 0; \
(pc)->k = (n); \
(pc)++; \
}
/*
* Number of scratch memory words (for BPF_LD|BPF_MEM and BPF_ST).
*/
#define BPF_MEMWORDS 16
/*
* Link level header can be accessed by adding BPF_DLBASE to an offset.
*/
#define BPF_DLBASE (1<<30)
#define BPF_BYTES(n) ((n) * sizeof (struct bpf_insn))
#define BPF_BYTES2LEN(n) ((n) / sizeof (struct bpf_insn))
#define BPF_INSN_EQ(p,q) ((p)->code == (q)->code && \
(p)->jt == (q)->jt && \
(p)->jf == (q)->jf && \
(p)->k == (q)->k)
#endif /* _DEVICE_BPF_H_ */
|