summaryrefslogtreecommitdiff
path: root/sys/net/bpf.h
blob: 1b3427b61d8b6c57646ee57fdad37cd72c34b76b (plain)
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
247
248
249
250
251
252
253
254
/*	$OpenBSD: bpf.h,v 1.2 1996/03/03 21:07:02 niklas Exp $	*/
/*	$NetBSD: bpf.h,v 1.13 1996/02/13 21:59:58 christos Exp $	*/

/*
 * Copyright (c) 1990, 1991, 1993
 *	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.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 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	8.1 (Berkeley) 6/10/93
 */

#ifndef _NET_BPF_H_
#define _NET_BPF_H_

/*
 * Alignment macros.  BPF_WORDALIGN rounds up to the next 
 * even multiple of BPF_ALIGNMENT. 
 */
#define BPF_ALIGNMENT sizeof(long)
#define BPF_WORDALIGN(x) (((x)+(BPF_ALIGNMENT-1))&~(BPF_ALIGNMENT-1))

#define BPF_MAXINSNS 512
#define BPF_MAXBUFSIZE 0x8000
#define BPF_MINBUFSIZE 32

/*
 *  Structure for BIOCSETF.
 */
struct bpf_program {
	u_int bf_len;
	struct bpf_insn *bf_insns;
};
 
/*
 * Struct returned by BIOCGSTATS.
 */
struct bpf_stat {
	u_int bs_recv;		/* number of packets received */
	u_int bs_drop;		/* number of packets dropped */
};

/*
 * 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 of filter architecture. */
#define BPF_MAJOR_VERSION 1
#define BPF_MINOR_VERSION 1

/*
 * BPF ioctls
 *
 * The first set is for compatibility with Sun's pcc style
 * header files.  If your using gcc, we assume that you
 * have run fixincludes so the latter set should work.
 */
#if (defined(sun) || defined(ibm032)) && !defined(__GNUC__)
#define	BIOCGBLEN	_IOR(B,102, u_int)
#define	BIOCSBLEN	_IOWR(B,102, u_int)
#define	BIOCSETF	_IOW(B,103, struct bpf_program)
#define	BIOCFLUSH	_IO(B,104)
#define BIOCPROMISC	_IO(B,105)
#define	BIOCGDLT	_IOR(B,106, u_int)
#define BIOCGETIF	_IOR(B,107, struct ifreq)
#define BIOCSETIF	_IOW(B,108, struct ifreq)
#define BIOCSRTIMEOUT	_IOW(B,109, struct timeval)
#define BIOCGRTIMEOUT	_IOR(B,110, struct timeval)
#define BIOCGSTATS	_IOR(B,111, struct bpf_stat)
#define BIOCIMMEDIATE	_IOW(B,112, u_int)
#define BIOCVERSION	_IOR(B,113, struct bpf_version)
#define BIOCSRSIG	_IOW(B,114, u_int)
#define BIOCGRSIG	_IOR(B,115, u_int)
#else
#define	BIOCGBLEN	_IOR('B',102, u_int)
#define	BIOCSBLEN	_IOWR('B',102, u_int)
#define	BIOCSETF	_IOW('B',103, struct bpf_program)
#define	BIOCFLUSH	_IO('B',104)
#define BIOCPROMISC	_IO('B',105)
#define	BIOCGDLT	_IOR('B',106, u_int)
#define BIOCGETIF	_IOR('B',107, struct ifreq)
#define BIOCSETIF	_IOW('B',108, struct ifreq)
#define BIOCSRTIMEOUT	_IOW('B',109, struct timeval)
#define BIOCGRTIMEOUT	_IOR('B',110, struct timeval)
#define BIOCGSTATS	_IOR('B',111, struct bpf_stat)
#define BIOCIMMEDIATE	_IOW('B',112, u_int)
#define BIOCVERSION	_IOR('B',113, struct bpf_version)
#define BIOCSRSIG	_IOW('B',114, u_int)
#define BIOCGRSIG	_IOR('B',115, u_int)
#endif

/*
 * Structure prepended to each packet.
 */
struct bpf_hdr {
	struct timeval	bh_tstamp;	/* time stamp */
	u_int32_t	bh_caplen;	/* length of captured portion */
	u_int32_t	bh_datalen;	/* original length of packet */
	u_int16_t	bh_hdrlen;	/* length of bpf header (this struct
					   plus alignment padding) */
};
/*
 * Because the structure above is not a multiple of 4 bytes, some compilers
 * will insist on inserting padding; hence, sizeof(struct bpf_hdr) won't work.
 * Only the kernel needs to know about it; applications use bh_hdrlen.
 */
#ifdef _KERNEL
#define SIZEOF_BPF_HDR 18
#endif

/*
 * Data-link level type codes.
 */
#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.
 */
/* 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_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) & 0x18)
#define		BPF_A		0x10

/* misc */
#define BPF_MISCOP(code) ((code) & 0xf8)
#define		BPF_TAX		0x00
#define		BPF_TXA		0x80

/*
 * The instruction data structure.
 */
struct bpf_insn {
	u_int16_t code;
	u_char 	  jt;
	u_char 	  jf;
	int32_t	  k;
};

/*
 * Macros for insn array initializers.
 */
#define BPF_STMT(code, k) { (u_int16_t)(code), 0, 0, k }
#define BPF_JUMP(code, k, jt, jf) { (u_int16_t)(code), jt, jf, k }

#ifdef _KERNEL
int	 bpf_validate __P((struct bpf_insn *, int));
void	 bpf_tap __P((caddr_t, u_char *, u_int));
void	 bpf_mtap __P((caddr_t, struct mbuf *));
void	 bpfattach __P((caddr_t *, struct ifnet *, u_int, u_int));
void	 bpfilterattach __P((int));
u_int	 bpf_filter __P((struct bpf_insn *, u_char *, u_int, u_int));
#endif

/*
 * Number of scratch memory words (for BPF_LD|BPF_MEM and BPF_ST).
 */
#define BPF_MEMWORDS 16

#endif /* _NET_BPF_H_ */