bpf.h revision 1.29 1 /* $NetBSD: bpf.h,v 1.29 2001/12/14 23:30:02 thorpej 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 8.2 (Berkeley) 1/9/95
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 #include <sys/time.h>
48
49 /* BSD style release date */
50 #define BPF_RELEASE 199606
51
52 typedef int bpf_int32;
53 typedef u_int bpf_u_int32;
54
55 /*
56 * Alignment macros. BPF_WORDALIGN rounds up to the next
57 * even multiple of BPF_ALIGNMENT.
58 */
59 #define BPF_ALIGNMENT sizeof(long)
60 #define BPF_WORDALIGN(x) (((x)+(BPF_ALIGNMENT-1))&~(BPF_ALIGNMENT-1))
61
62 #define BPF_MAXINSNS 512
63 #define BPF_MAXBUFSIZE 0x8000
64 #define BPF_MINBUFSIZE 32
65
66 /*
67 * Structure for BIOCSETF.
68 */
69 struct bpf_program {
70 u_int bf_len;
71 struct bpf_insn *bf_insns;
72 };
73
74 /*
75 * Struct returned by BIOCGSTATS.
76 */
77 struct bpf_stat {
78 u_int bs_recv; /* number of packets received */
79 u_int bs_drop; /* number of packets dropped */
80 };
81
82 /*
83 * Struct return by BIOCVERSION. This represents the version number of
84 * the filter language described by the instruction encodings below.
85 * bpf understands a program iff kernel_major == filter_major &&
86 * kernel_minor >= filter_minor, that is, if the value returned by the
87 * running kernel has the same major number and a minor number equal
88 * equal to or less than the filter being downloaded. Otherwise, the
89 * results are undefined, meaning an error may be returned or packets
90 * may be accepted haphazardly.
91 * It has nothing to do with the source code version.
92 */
93 struct bpf_version {
94 u_short bv_major;
95 u_short bv_minor;
96 };
97 /* Current version number of filter architecture. */
98 #define BPF_MAJOR_VERSION 1
99 #define BPF_MINOR_VERSION 1
100
101 /*
102 * BPF ioctls
103 *
104 * The first set is for compatibility with Sun's pcc style
105 * header files. If your using gcc, we assume that you
106 * have run fixincludes so the latter set should work.
107 */
108 #if (defined(sun) || defined(ibm032)) && !defined(__GNUC__)
109 #define BIOCGBLEN _IOR(B,102, u_int)
110 #define BIOCSBLEN _IOWR(B,102, u_int)
111 #define BIOCSETF _IOW(B,103, struct bpf_program)
112 #define BIOCFLUSH _IO(B,104)
113 #define BIOCPROMISC _IO(B,105)
114 #define BIOCGDLT _IOR(B,106, u_int)
115 #define BIOCGETIF _IOR(B,107, struct ifreq)
116 #define BIOCSETIF _IOW(B,108, struct ifreq)
117 #define BIOCSRTIMEOUT _IOW(B,109, struct timeval)
118 #define BIOCGRTIMEOUT _IOR(B,110, struct timeval)
119 #define BIOCGSTATS _IOR(B,111, struct bpf_stat)
120 #define BIOCIMMEDIATE _IOW(B,112, u_int)
121 #define BIOCVERSION _IOR(B,113, struct bpf_version)
122 #define BIOCSTCPF _IOW(B,114, struct bpf_program)
123 #define BIOCSUDPF _IOW(B,115, struct bpf_program)
124 #define BIOCGHDRCMPLT _IOR(B,116, u_int)
125 #define BIOCSHDRCMPLT _IOW(B,117, u_int)
126 #else
127 #define BIOCGBLEN _IOR('B',102, u_int)
128 #define BIOCSBLEN _IOWR('B',102, u_int)
129 #define BIOCSETF _IOW('B',103, struct bpf_program)
130 #define BIOCFLUSH _IO('B',104)
131 #define BIOCPROMISC _IO('B',105)
132 #define BIOCGDLT _IOR('B',106, u_int)
133 #define BIOCGETIF _IOR('B',107, struct ifreq)
134 #define BIOCSETIF _IOW('B',108, struct ifreq)
135 #define BIOCSRTIMEOUT _IOW('B',109, struct timeval)
136 #define BIOCGRTIMEOUT _IOR('B',110, struct timeval)
137 #define BIOCGSTATS _IOR('B',111, struct bpf_stat)
138 #define BIOCIMMEDIATE _IOW('B',112, u_int)
139 #define BIOCVERSION _IOR('B',113, struct bpf_version)
140 #define BIOCSTCPF _IOW('B',114, struct bpf_program)
141 #define BIOCSUDPF _IOW('B',115, struct bpf_program)
142 #define BIOCGHDRCMPLT _IOR('B',116, u_int)
143 #define BIOCSHDRCMPLT _IOW('B',117, u_int)
144 #endif
145
146 /*
147 * Structure prepended to each packet.
148 */
149 struct bpf_hdr {
150 struct timeval bh_tstamp; /* time stamp */
151 u_int32_t bh_caplen; /* length of captured portion */
152 u_int32_t bh_datalen; /* original length of packet */
153 u_int16_t bh_hdrlen; /* length of bpf header (this struct
154 plus alignment padding) */
155 };
156 /*
157 * Because the structure above is not a multiple of 4 bytes, some compilers
158 * will insist on inserting padding; hence, sizeof(struct bpf_hdr) won't work.
159 * Only the kernel needs to know about it; applications use bh_hdrlen.
160 * XXX To save a few bytes on 32-bit machines, we avoid end-of-struct
161 * XXX padding by using the size of the header data elements. This is
162 * XXX fail-safe: on new machines, we just use the 'safe' sizeof.
163 */
164 #ifdef _KERNEL
165 #if defined(__arm32__) || defined(__i386__) || defined(__m68k__) || \
166 defined(__mips__) || defined(__ns32k__) || defined(__vax__) || \
167 defined(__sh__) || (defined(__sparc__) && !defined(__sparc64__))
168 #define SIZEOF_BPF_HDR 18
169 #else
170 #define SIZEOF_BPF_HDR sizeof(struct bpf_hdr)
171 #endif
172 #endif
173
174 /* Pull in data-link level type codes. */
175 #include <net/dlt.h>
176
177 /*
178 * The instruction encondings.
179 */
180 /* instruction classes */
181 #define BPF_CLASS(code) ((code) & 0x07)
182 #define BPF_LD 0x00
183 #define BPF_LDX 0x01
184 #define BPF_ST 0x02
185 #define BPF_STX 0x03
186 #define BPF_ALU 0x04
187 #define BPF_JMP 0x05
188 #define BPF_RET 0x06
189 #define BPF_MISC 0x07
190
191 /* ld/ldx fields */
192 #define BPF_SIZE(code) ((code) & 0x18)
193 #define BPF_W 0x00
194 #define BPF_H 0x08
195 #define BPF_B 0x10
196 #define BPF_MODE(code) ((code) & 0xe0)
197 #define BPF_IMM 0x00
198 #define BPF_ABS 0x20
199 #define BPF_IND 0x40
200 #define BPF_MEM 0x60
201 #define BPF_LEN 0x80
202 #define BPF_MSH 0xa0
203
204 /* alu/jmp fields */
205 #define BPF_OP(code) ((code) & 0xf0)
206 #define BPF_ADD 0x00
207 #define BPF_SUB 0x10
208 #define BPF_MUL 0x20
209 #define BPF_DIV 0x30
210 #define BPF_OR 0x40
211 #define BPF_AND 0x50
212 #define BPF_LSH 0x60
213 #define BPF_RSH 0x70
214 #define BPF_NEG 0x80
215 #define BPF_JA 0x00
216 #define BPF_JEQ 0x10
217 #define BPF_JGT 0x20
218 #define BPF_JGE 0x30
219 #define BPF_JSET 0x40
220 #define BPF_SRC(code) ((code) & 0x08)
221 #define BPF_K 0x00
222 #define BPF_X 0x08
223
224 /* ret - BPF_K and BPF_X also apply */
225 #define BPF_RVAL(code) ((code) & 0x18)
226 #define BPF_A 0x10
227
228 /* misc */
229 #define BPF_MISCOP(code) ((code) & 0xf8)
230 #define BPF_TAX 0x00
231 #define BPF_TXA 0x80
232
233 /*
234 * The instruction data structure.
235 */
236 struct bpf_insn {
237 u_int16_t code;
238 u_char jt;
239 u_char jf;
240 int32_t k;
241 };
242
243 /*
244 * Macros for insn array initializers.
245 */
246 #define BPF_STMT(code, k) { (u_int16_t)(code), 0, 0, k }
247 #define BPF_JUMP(code, k, jt, jf) { (u_int16_t)(code), jt, jf, k }
248
249 #ifdef _KERNEL
250 int bpf_validate __P((struct bpf_insn *, int));
251 void bpf_tap __P((caddr_t, u_char *, u_int));
252 void bpf_mtap __P((caddr_t, struct mbuf *));
253 void bpfattach __P((struct ifnet *, u_int, u_int));
254 void bpfdetach __P((struct ifnet *));
255 void bpf_change_type __P((struct ifnet *, u_int, u_int));
256 void bpfilterattach __P((int));
257 #endif
258
259 u_int bpf_filter __P((struct bpf_insn *, u_char *, u_int, u_int));
260
261 /*
262 * Number of scratch memory words (for BPF_LD|BPF_MEM and BPF_ST).
263 */
264 #define BPF_MEMWORDS 16
265
266 #endif /* _NET_BPF_H_ */
267