bpf.h revision 1.18 1 /* $NetBSD: bpf.h,v 1.18 1997/10/10 14:15:32 christos Exp $ */
2
3 /*
4 * Copyright (c) 1990, 1991, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * This code is derived from the Stanford/CMU enet packet filter,
8 * (net/enet.c) distributed as part of 4.3BSD, and code contributed
9 * to Berkeley by Steven McCanne and Van Jacobson both of Lawrence
10 * Berkeley Laboratory.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. All advertising materials mentioning features or use of this software
21 * must display the following acknowledgement:
22 * This product includes software developed by the University of
23 * California, Berkeley and its contributors.
24 * 4. Neither the name of the University nor the names of its contributors
25 * may be used to endorse or promote products derived from this software
26 * without specific prior written permission.
27 *
28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38 * SUCH DAMAGE.
39 *
40 * @(#)bpf.h 8.1 (Berkeley) 6/10/93
41 * @(#) Header: bpf.h,v 1.36 97/06/12 14:29:53 leres Exp (LBL)
42 */
43
44 #ifndef _NET_BPF_H_
45 #define _NET_BPF_H_
46
47 /* BSD style release date */
48 #define BPF_RELEASE 199606
49
50 typedef int bpf_int32;
51 typedef u_int bpf_u_int32;
52
53 /*
54 * Alignment macros. BPF_WORDALIGN rounds up to the next
55 * even multiple of BPF_ALIGNMENT.
56 */
57 #define BPF_ALIGNMENT sizeof(long)
58 #define BPF_WORDALIGN(x) (((x)+(BPF_ALIGNMENT-1))&~(BPF_ALIGNMENT-1))
59
60 #define BPF_MAXINSNS 512
61 #define BPF_MAXBUFSIZE 0x8000
62 #define BPF_MINBUFSIZE 32
63
64 /*
65 * Structure for BIOCSETF.
66 */
67 struct bpf_program {
68 u_int bf_len;
69 struct bpf_insn *bf_insns;
70 };
71
72 /*
73 * Struct returned by BIOCGSTATS.
74 */
75 struct bpf_stat {
76 u_int bs_recv; /* number of packets received */
77 u_int bs_drop; /* number of packets dropped */
78 };
79
80 /*
81 * Struct return by BIOCVERSION. This represents the version number of
82 * the filter language described by the instruction encodings below.
83 * bpf understands a program iff kernel_major == filter_major &&
84 * kernel_minor >= filter_minor, that is, if the value returned by the
85 * running kernel has the same major number and a minor number equal
86 * equal to or less than the filter being downloaded. Otherwise, the
87 * results are undefined, meaning an error may be returned or packets
88 * may be accepted haphazardly.
89 * It has nothing to do with the source code version.
90 */
91 struct bpf_version {
92 u_short bv_major;
93 u_short bv_minor;
94 };
95 /* Current version number of filter architecture. */
96 #define BPF_MAJOR_VERSION 1
97 #define BPF_MINOR_VERSION 1
98
99 /*
100 * BPF ioctls
101 *
102 * The first set is for compatibility with Sun's pcc style
103 * header files. If your using gcc, we assume that you
104 * have run fixincludes so the latter set should work.
105 */
106 #if (defined(sun) || defined(ibm032)) && !defined(__GNUC__)
107 #define BIOCGBLEN _IOR(B,102, u_int)
108 #define BIOCSBLEN _IOWR(B,102, u_int)
109 #define BIOCSETF _IOW(B,103, struct bpf_program)
110 #define BIOCFLUSH _IO(B,104)
111 #define BIOCPROMISC _IO(B,105)
112 #define BIOCGDLT _IOR(B,106, u_int)
113 #define BIOCGETIF _IOR(B,107, struct ifreq)
114 #define BIOCSETIF _IOW(B,108, struct ifreq)
115 #define BIOCSRTIMEOUT _IOW(B,109, struct timeval)
116 #define BIOCGRTIMEOUT _IOR(B,110, struct timeval)
117 #define BIOCGSTATS _IOR(B,111, struct bpf_stat)
118 #define BIOCIMMEDIATE _IOW(B,112, u_int)
119 #define BIOCVERSION _IOR(B,113, struct bpf_version)
120 #define BIOCSTCPF _IOW(B,114, struct bpf_program)
121 #define BIOCSUDPF _IOW(B,115, struct bpf_program)
122 #else
123 #define BIOCGBLEN _IOR('B',102, u_int)
124 #define BIOCSBLEN _IOWR('B',102, u_int)
125 #define BIOCSETF _IOW('B',103, struct bpf_program)
126 #define BIOCFLUSH _IO('B',104)
127 #define BIOCPROMISC _IO('B',105)
128 #define BIOCGDLT _IOR('B',106, u_int)
129 #define BIOCGETIF _IOR('B',107, struct ifreq)
130 #define BIOCSETIF _IOW('B',108, struct ifreq)
131 #define BIOCSRTIMEOUT _IOW('B',109, struct timeval)
132 #define BIOCGRTIMEOUT _IOR('B',110, struct timeval)
133 #define BIOCGSTATS _IOR('B',111, struct bpf_stat)
134 #define BIOCIMMEDIATE _IOW('B',112, u_int)
135 #define BIOCVERSION _IOR('B',113, struct bpf_version)
136 #define BIOCSTCPF _IOW('B',114, struct bpf_program)
137 #define BIOCSUDPF _IOW('B',115, struct bpf_program)
138 #endif
139
140 /*
141 * Structure prepended to each packet.
142 */
143 struct bpf_hdr {
144 struct timeval bh_tstamp; /* time stamp */
145 u_int32_t bh_caplen; /* length of captured portion */
146 u_int32_t bh_datalen; /* original length of packet */
147 u_int16_t bh_hdrlen; /* length of bpf header (this struct
148 plus alignment padding) */
149 };
150 /*
151 * Because the structure above is not a multiple of 4 bytes, some compilers
152 * will insist on inserting padding; hence, sizeof(struct bpf_hdr) won't work.
153 * Only the kernel needs to know about it; applications use bh_hdrlen.
154 * XXX To save a few bytes on 32-bit machines, we avoid end-of-struct
155 * XXX padding by using the size of the header data elements. This is
156 * XXX fail-safe: on new machines, we just use the 'safe' sizeof.
157 */
158 #ifdef _KERNEL
159 #if defined(__arm32__) || defined(__i386__) || defined(__m68k__) || \
160 defined(__mips__) || defined(__ns32k__) || defined(__sparc__) || \
161 defined(__vax__)
162 #define SIZEOF_BPF_HDR 18
163 #else
164 #define SIZEOF_BPF_HDR sizeof(struct bpf_hdr)
165 #endif
166 #endif
167
168 /*
169 * Data-link level type codes.
170 */
171 #define DLT_NULL 0 /* no link-layer encapsulation */
172 #define DLT_EN10MB 1 /* Ethernet (10Mb) */
173 #define DLT_EN3MB 2 /* Experimental Ethernet (3Mb) */
174 #define DLT_AX25 3 /* Amateur Radio AX.25 */
175 #define DLT_PRONET 4 /* Proteon ProNET Token Ring */
176 #define DLT_CHAOS 5 /* Chaos */
177 #define DLT_IEEE802 6 /* IEEE 802 Networks */
178 #define DLT_ARCNET 7 /* ARCNET */
179 #define DLT_SLIP 8 /* Serial Line IP */
180 #define DLT_PPP 9 /* Point-to-point Protocol */
181 #define DLT_FDDI 10 /* FDDI */
182 #define DLT_ATM_RFC1483 11 /* LLC/SNAP encapsulated atm */
183 #define DLT_RAW 12 /* raw IP */
184 #define DLT_SLIP_BSDOS 13 /* BSD/OS Serial Line IP */
185 #define DLT_PPP_BSDOS 14 /* BSD/OS Point-to-point Protocol */
186
187 /*
188 * The instruction encondings.
189 */
190 /* instruction classes */
191 #define BPF_CLASS(code) ((code) & 0x07)
192 #define BPF_LD 0x00
193 #define BPF_LDX 0x01
194 #define BPF_ST 0x02
195 #define BPF_STX 0x03
196 #define BPF_ALU 0x04
197 #define BPF_JMP 0x05
198 #define BPF_RET 0x06
199 #define BPF_MISC 0x07
200
201 /* ld/ldx fields */
202 #define BPF_SIZE(code) ((code) & 0x18)
203 #define BPF_W 0x00
204 #define BPF_H 0x08
205 #define BPF_B 0x10
206 #define BPF_MODE(code) ((code) & 0xe0)
207 #define BPF_IMM 0x00
208 #define BPF_ABS 0x20
209 #define BPF_IND 0x40
210 #define BPF_MEM 0x60
211 #define BPF_LEN 0x80
212 #define BPF_MSH 0xa0
213
214 /* alu/jmp fields */
215 #define BPF_OP(code) ((code) & 0xf0)
216 #define BPF_ADD 0x00
217 #define BPF_SUB 0x10
218 #define BPF_MUL 0x20
219 #define BPF_DIV 0x30
220 #define BPF_OR 0x40
221 #define BPF_AND 0x50
222 #define BPF_LSH 0x60
223 #define BPF_RSH 0x70
224 #define BPF_NEG 0x80
225 #define BPF_JA 0x00
226 #define BPF_JEQ 0x10
227 #define BPF_JGT 0x20
228 #define BPF_JGE 0x30
229 #define BPF_JSET 0x40
230 #define BPF_SRC(code) ((code) & 0x08)
231 #define BPF_K 0x00
232 #define BPF_X 0x08
233
234 /* ret - BPF_K and BPF_X also apply */
235 #define BPF_RVAL(code) ((code) & 0x18)
236 #define BPF_A 0x10
237
238 /* misc */
239 #define BPF_MISCOP(code) ((code) & 0xf8)
240 #define BPF_TAX 0x00
241 #define BPF_TXA 0x80
242
243 /*
244 * The instruction data structure.
245 */
246 struct bpf_insn {
247 u_int16_t code;
248 u_char jt;
249 u_char jf;
250 int32_t k;
251 };
252
253 /*
254 * Macros for insn array initializers.
255 */
256 #define BPF_STMT(code, k) { (u_int16_t)(code), 0, 0, k }
257 #define BPF_JUMP(code, k, jt, jf) { (u_int16_t)(code), jt, jf, k }
258
259 #ifdef _KERNEL
260 int bpf_validate __P((struct bpf_insn *, int));
261 void bpf_tap __P((caddr_t, u_char *, u_int));
262 void bpf_mtap __P((caddr_t, struct mbuf *));
263 void bpfattach __P((caddr_t *, struct ifnet *, u_int, u_int));
264 void bpfilterattach __P((int));
265 #endif
266
267 u_int bpf_filter __P((struct bpf_insn *, u_char *, u_int, u_int));
268
269 /*
270 * Number of scratch memory words (for BPF_LD|BPF_MEM and BPF_ST).
271 */
272 #define BPF_MEMWORDS 16
273
274 #endif /* _NET_BPF_H_ */
275