xref: /csrg-svn/sys/net/bpf.h (revision 51427)
1 /*-
2  * Copyright (c) 1990-1991 The Regents of the University of California.
3  * 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  * @(#) $Header: bpf.h,v 1.24 91/10/27 21:22:32 mccanne Exp $ (LBL)
41  */
42 
43 /*
44  * Alignment macros.  BPF_WORDALIGN rounds up to the next
45  * even multiple of BPF_ALIGNMENT.
46  */
47 #define BPF_ALIGNMENT sizeof(long)
48 #define BPF_WORDALIGN(x) (((x)+(BPF_ALIGNMENT-1))&~(BPF_ALIGNMENT-1))
49 
50 #define BPF_MAXINSNS 512
51 #define BPF_MAXBUFSIZE 0x8000
52 
53 /*
54  *  Structure for BIOCSETF.
55  */
56 struct bpf_program {
57 	u_int bf_len;
58 	struct bpf_insn *bf_insns;
59 };
60 
61 /*
62  * Struct returned by BIOCGSTATS.
63  */
64 struct bpf_stat {
65 	u_int bs_recv;		/* number of packets received */
66 	u_int bs_drop;		/* number of packets dropped */
67 };
68 
69 /*
70  * BPF ioctls
71  *
72  * The first set is for compatibility with Sun's pcc style
73  * header files.  If your using gcc, we assume that you
74  * have run fixincludes so the latter set should work.
75  */
76 #if (defined(sun) || defined(ibm032)) && !defined(__GNUC__)
77 #define	BIOCGBLEN	_IOR(B,102, u_int)
78 #define	BIOCSBLEN	_IOWR(B,102, u_int)
79 #define	BIOCSETF	_IOW(B,103, struct bpf_program)
80 #define	BIOCFLUSH	_IO(B,104)
81 #define BIOCPROMISC	_IO(B,105)
82 #define	BIOCGDLT	_IOR(B,106, u_int)
83 #define BIOCGETIF	_IOR(B,107, struct ifreq)
84 #define BIOCSETIF	_IOW(B,108, struct ifreq)
85 #define BIOCSRTIMEOUT	_IOW(B,109, struct timeval)
86 #define BIOCGRTIMEOUT	_IOR(B,110, struct timeval)
87 #define BIOCGSTATS	_IOR(B,111, struct bpf_stat)
88 #define BIOCIMMEDIATE	_IOW(B,112, u_int)
89 #else
90 #define	BIOCGBLEN	_IOR('B',102, u_int)
91 #define	BIOCSBLEN	_IOWR('B',102, u_int)
92 #define	BIOCSETF	_IOW('B',103, struct bpf_program)
93 #define	BIOCFLUSH	_IO('B',104)
94 #define BIOCPROMISC	_IO('B',105)
95 #define	BIOCGDLT	_IOR('B',106, u_int)
96 #define BIOCGETIF	_IOR('B',107, struct ifreq)
97 #define BIOCSETIF	_IOW('B',108, struct ifreq)
98 #define BIOCSRTIMEOUT	_IOW('B',109, struct timeval)
99 #define BIOCGRTIMEOUT	_IOR('B',110, struct timeval)
100 #define BIOCGSTATS	_IOR('B',111, struct bpf_stat)
101 #define BIOCIMMEDIATE	_IOW('B',112, u_int)
102 #endif
103 
104 /*
105  * Structure prepended to each packet.
106  */
107 struct bpf_hdr {
108 	struct timeval	bh_tstamp;	/* time stamp */
109 	u_long		bh_caplen;	/* length of captured portion */
110 	u_long		bh_datalen;	/* original length of packet */
111 	u_short		bh_hdrlen;	/* length of bpf header (this struct
112 					   plus alignment padding) */
113 };
114 /*
115  * Because the structure above is not a multiple of 4 bytes, some compilers
116  * will insist on inserting padding; hence, sizeof(struct bpf_hdr) won't work.
117  * Only the kernel needs to know about it; applications use bh_hdrlen.
118  */
119 #ifdef KERNEL
120 #define SIZEOF_BPF_HDR 18
121 #endif
122 
123 /*
124  * Data-link level type codes.
125  * Currently, only DLT_EN10MB and DLT_SLIP are supported.
126  */
127 #define DLT_NULL	0	/* no link-layer encapsulation */
128 #define DLT_EN10MB	1	/* Ethernet (10Mb) */
129 #define DLT_EN3MB	2	/* Experimental Ethernet (3Mb) */
130 #define DLT_AX25	3	/* Amateur Radio AX.25 */
131 #define DLT_PRONET	4	/* Proteon ProNET Token Ring */
132 #define DLT_CHAOS	5	/* Chaos */
133 #define DLT_IEEE802	6	/* IEEE 802 Networks */
134 #define DLT_ARCNET	7	/* ARCNET */
135 #define DLT_SLIP	8	/* Serial Line IP */
136 #define DLT_PPP		9	/* Point-to-point Protocol */
137 #define DLT_FDDI	10	/* FDDI */
138 
139 /*
140  * The instruction encondings.
141  */
142 /* classes <2:0> */
143 #define BPF_CLASS(code) ((code) & 0x07)
144 #define		BPF_LD		0x00
145 #define		BPF_LDX		0x01
146 #define		BPF_ST		0x02
147 #define		BPF_STX		0x03
148 #define		BPF_ALU		0x04
149 #define		BPF_JMP		0x05
150 #define		BPF_RET		0x06
151 #define		BPF_MISC	0x07
152 
153 /* ld/ldx fields */
154 #define BPF_SIZE(code)	((code) & 0x18)
155 #define		BPF_W		0x00
156 #define		BPF_H		0x08
157 #define		BPF_B		0x10
158 #define BPF_MODE(code)	((code) & 0xe0)
159 #define		BPF_IMM 	0x00
160 #define		BPF_ABS		0x20
161 #define		BPF_IND		0x40
162 #define		BPF_MEM		0x60
163 #define		BPF_LEN		0x80
164 #define		BPF_MSH		0xa0
165 
166 /* alu/jmp fields */
167 #define BPF_OP(code)	((code) & 0xf0)
168 #define		BPF_ADD		0x00
169 #define		BPF_SUB		0x10
170 #define		BPF_MUL		0x20
171 #define		BPF_DIV		0x30
172 #define		BPF_OR		0x40
173 #define		BPF_AND		0x50
174 #define		BPF_LSH		0x60
175 #define		BPF_RSH		0x70
176 #define		BPF_NEG		0x80
177 #define		BPF_JA		0x00
178 #define		BPF_JEQ		0x10
179 #define		BPF_JGT		0x20
180 #define		BPF_JGE		0x30
181 #define		BPF_JSET	0x40
182 #define BPF_SRC(code)	((code) & 0x08)
183 #define		BPF_K		0x00
184 #define		BPF_X		0x08
185 
186 /* ret - BPF_K and BPF_X also apply */
187 #define BPF_RVAL(code)	((code) & 0x18)
188 #define		BPF_A		0x10
189 
190 /* misc */
191 #define BPF_MISCOP(code) ((code) & 0xf8)
192 #define		BPF_TAX		0x00
193 #define		BPF_TXA		0x80
194 
195 /*
196  * The instruction data structure.
197  */
198 struct bpf_insn {
199 	u_short	code;
200 	u_char 	jt;
201 	u_char 	jf;
202 	long	k;
203 };
204 
205 /*
206  * Macros for insn array initializers.
207  */
208 #define BPF_STMT(code, k) { (u_short)(code), 0, 0, k }
209 #define BPF_JUMP(code, k, jt, jf) { (u_short)(code), jt, jf, k }
210 
211 #ifdef KERNEL
212 extern u_int bpf_filter();
213 extern void bpfattach();
214 extern void bpf_tap();
215 extern void bpf_mtap();
216 #endif
217 
218 /*
219  * Number of scratch memory words (for BPF_LD|BPF_MEM and BPF_ST).
220  */
221 #define BPF_MEMWORDS 16
222 
223