xref: /netbsd-src/sys/net/bpf.h (revision 7f21db1c0118155e0dd40b75182e30c589d9f63e)
1 /*	$NetBSD: bpf.h,v 1.53 2010/01/25 22:18:17 pooka 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. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  *	@(#)bpf.h	8.2 (Berkeley) 1/9/95
37  * @(#) Header: bpf.h,v 1.36 97/06/12 14:29:53 leres Exp  (LBL)
38  */
39 
40 #ifndef _NET_BPF_H_
41 #define _NET_BPF_H_
42 
43 #include <sys/time.h>
44 
45 /* BSD style release date */
46 #define BPF_RELEASE 199606
47 
48 typedef	int bpf_int32;
49 typedef	u_int bpf_u_int32;
50 
51 /*
52  * Alignment macros.  BPF_WORDALIGN rounds up to the next
53  * even multiple of BPF_ALIGNMENT.
54  */
55 #define BPF_ALIGNMENT sizeof(long)
56 #define BPF_WORDALIGN(x) (((x)+(BPF_ALIGNMENT-1))&~(BPF_ALIGNMENT-1))
57 
58 #define BPF_MAXINSNS 512
59 #define BPF_DFLTBUFSIZE (1024*1024)	/* default static upper limit */
60 #define BPF_MAXBUFSIZE (1024*1024*16)	/* hard limit on sysctl'able value */
61 #define BPF_MINBUFSIZE 32
62 
63 /*
64  *  Structure for BIOCSETF.
65  */
66 struct bpf_program {
67 	u_int bf_len;
68 	struct bpf_insn *bf_insns;
69 };
70 
71 /*
72  * Struct returned by BIOCGSTATS and net.bpf.stats sysctl.
73  */
74 struct bpf_stat {
75 	uint64_t bs_recv;	/* number of packets received */
76 	uint64_t bs_drop;	/* number of packets dropped */
77 	uint64_t bs_capt;	/* number of packets captured */
78 	uint64_t bs_padding[13];
79 };
80 
81 /*
82  * Struct returned by BIOCGSTATSOLD.
83  */
84 struct bpf_stat_old {
85 	u_int bs_recv;		/* number of packets received */
86 	u_int bs_drop;		/* number of packets dropped */
87 };
88 
89 /*
90  * Struct return by BIOCVERSION.  This represents the version number of
91  * the filter language described by the instruction encodings below.
92  * bpf understands a program iff kernel_major == filter_major &&
93  * kernel_minor >= filter_minor, that is, if the value returned by the
94  * running kernel has the same major number and a minor number equal
95  * equal to or less than the filter being downloaded.  Otherwise, the
96  * results are undefined, meaning an error may be returned or packets
97  * may be accepted haphazardly.
98  * It has nothing to do with the source code version.
99  */
100 struct bpf_version {
101 	u_short bv_major;
102 	u_short bv_minor;
103 };
104 /* Current version number of filter architecture. */
105 #define BPF_MAJOR_VERSION 1
106 #define BPF_MINOR_VERSION 1
107 
108 /*
109  * BPF ioctls
110  *
111  * The first set is for compatibility with Sun's pcc style
112  * header files.  If your using gcc, we assume that you
113  * have run fixincludes so the latter set should work.
114  */
115 #define BIOCGBLEN	 _IOR('B',102, u_int)
116 #define BIOCSBLEN	_IOWR('B',102, u_int)
117 #define BIOCSETF	 _IOW('B',103, struct bpf_program)
118 #define BIOCFLUSH	  _IO('B',104)
119 #define BIOCPROMISC	  _IO('B',105)
120 #define BIOCGDLT	 _IOR('B',106, u_int)
121 #define BIOCGETIF	 _IOR('B',107, struct ifreq)
122 #define BIOCSETIF	 _IOW('B',108, struct ifreq)
123 #ifdef COMPAT_50
124 #include <compat/sys/time.h>
125 #define BIOCSORTIMEOUT	 _IOW('B',109, struct timeval50)
126 #define BIOCGORTIMEOUT	 _IOR('B',110, struct timeval50)
127 #endif
128 #define BIOCGSTATS	 _IOR('B',111, struct bpf_stat)
129 #define BIOCGSTATSOLD	 _IOR('B',111, struct bpf_stat_old)
130 #define BIOCIMMEDIATE	 _IOW('B',112, u_int)
131 #define BIOCVERSION	 _IOR('B',113, struct bpf_version)
132 #define BIOCSTCPF	 _IOW('B',114, struct bpf_program)
133 #define BIOCSUDPF	 _IOW('B',115, struct bpf_program)
134 #define BIOCGHDRCMPLT	 _IOR('B',116, u_int)
135 #define BIOCSHDRCMPLT	 _IOW('B',117, u_int)
136 #define BIOCSDLT	 _IOW('B',118, u_int)
137 #define BIOCGDLTLIST	_IOWR('B',119, struct bpf_dltlist)
138 #define BIOCGSEESENT	 _IOR('B',120, u_int)
139 #define BIOCSSEESENT	 _IOW('B',121, u_int)
140 #define BIOCSRTIMEOUT	 _IOW('B',122, struct timeval)
141 #define BIOCGRTIMEOUT	 _IOR('B',123, struct timeval)
142 
143 /*
144  * Structure prepended to each packet. This is "wire" format, so we
145  * cannot change it unfortunately to 64 bit times on 32 bit systems [yet].
146  */
147 struct bpf_timeval {
148 	long tv_sec;
149 	long tv_usec;
150 };
151 
152 struct bpf_hdr {
153 	struct bpf_timeval bh_tstamp;	/* time stamp */
154 	uint32_t	bh_caplen;	/* length of captured portion */
155 	uint32_t	bh_datalen;	/* original length of packet */
156 	uint16_t	bh_hdrlen;	/* length of bpf header (this struct
157 					   plus alignment padding) */
158 };
159 /*
160  * Because the structure above is not a multiple of 4 bytes, some compilers
161  * will insist on inserting padding; hence, sizeof(struct bpf_hdr) won't work.
162  * Only the kernel needs to know about it; applications use bh_hdrlen.
163  * XXX To save a few bytes on 32-bit machines, we avoid end-of-struct
164  * XXX padding by using the size of the header data elements.  This is
165  * XXX fail-safe: on new machines, we just use the 'safe' sizeof.
166  */
167 #ifdef _KERNEL
168 #if defined(__arm32__) || defined(__i386__) || defined(__m68k__) || \
169     defined(__mips__) || defined(__ns32k__) || defined(__vax__) || \
170     defined(__sh__) || (defined(__sparc__) && !defined(__sparc64__))
171 #define SIZEOF_BPF_HDR 18
172 #else
173 #define SIZEOF_BPF_HDR sizeof(struct bpf_hdr)
174 #endif
175 #endif
176 
177 /* Pull in data-link level type codes. */
178 #include <net/dlt.h>
179 
180 /*
181  * The instruction encodings.
182  */
183 /* instruction classes */
184 #define BPF_CLASS(code) ((code) & 0x07)
185 #define		BPF_LD		0x00
186 #define		BPF_LDX		0x01
187 #define		BPF_ST		0x02
188 #define		BPF_STX		0x03
189 #define		BPF_ALU		0x04
190 #define		BPF_JMP		0x05
191 #define		BPF_RET		0x06
192 #define		BPF_MISC	0x07
193 
194 /* ld/ldx fields */
195 #define BPF_SIZE(code)	((code) & 0x18)
196 #define		BPF_W		0x00
197 #define		BPF_H		0x08
198 #define		BPF_B		0x10
199 #define BPF_MODE(code)	((code) & 0xe0)
200 #define		BPF_IMM 	0x00
201 #define		BPF_ABS		0x20
202 #define		BPF_IND		0x40
203 #define		BPF_MEM		0x60
204 #define		BPF_LEN		0x80
205 #define		BPF_MSH		0xa0
206 
207 /* alu/jmp fields */
208 #define BPF_OP(code)	((code) & 0xf0)
209 #define		BPF_ADD		0x00
210 #define		BPF_SUB		0x10
211 #define		BPF_MUL		0x20
212 #define		BPF_DIV		0x30
213 #define		BPF_OR		0x40
214 #define		BPF_AND		0x50
215 #define		BPF_LSH		0x60
216 #define		BPF_RSH		0x70
217 #define		BPF_NEG		0x80
218 #define		BPF_JA		0x00
219 #define		BPF_JEQ		0x10
220 #define		BPF_JGT		0x20
221 #define		BPF_JGE		0x30
222 #define		BPF_JSET	0x40
223 #define BPF_SRC(code)	((code) & 0x08)
224 #define		BPF_K		0x00
225 #define		BPF_X		0x08
226 
227 /* ret - BPF_K and BPF_X also apply */
228 #define BPF_RVAL(code)	((code) & 0x18)
229 #define		BPF_A		0x10
230 
231 /* misc */
232 #define BPF_MISCOP(code) ((code) & 0xf8)
233 #define		BPF_TAX		0x00
234 #define		BPF_TXA		0x80
235 
236 /*
237  * The instruction data structure.
238  */
239 struct bpf_insn {
240 	uint16_t  code;
241 	u_char 	  jt;
242 	u_char 	  jf;
243 	uint32_t  k;
244 };
245 
246 /*
247  * Macros for insn array initializers.
248  */
249 #define BPF_STMT(code, k) { (uint16_t)(code), 0, 0, k }
250 #define BPF_JUMP(code, k, jt, jf) { (uint16_t)(code), jt, jf, k }
251 
252 /*
253  * Structure to retrieve available DLTs for the interface.
254  */
255 struct bpf_dltlist {
256 	u_int	bfl_len;	/* number of bfd_list array */
257 	u_int	*bfl_list;	/* array of DLTs */
258 };
259 
260 #ifdef _KERNEL
261 struct bpf_if;
262 
263 struct bpf_ops {
264 	void (*bpf_attach)(struct ifnet *, u_int, u_int, struct bpf_if **);
265 	void (*bpf_detach)(struct ifnet *);
266 	void (*bpf_change_type)(struct ifnet *, u_int, u_int);
267 
268 	void (*bpf_tap)(struct bpf_if *, u_char *, u_int);
269 	void (*bpf_mtap)(struct bpf_if *, struct mbuf *);
270 	void (*bpf_mtap2)(struct bpf_if *, void *, u_int, struct mbuf *);
271 	void (*bpf_mtap_af)(struct bpf_if *, uint32_t, struct mbuf *);
272 	void (*bpf_mtap_et)(struct bpf_if *, uint16_t, struct mbuf *);
273 	void (*bpf_mtap_sl_in)(struct bpf_if *, u_char *, struct mbuf **);
274 	void (*bpf_mtap_sl_out)(struct bpf_if *, u_char *, struct mbuf *);
275 };
276 extern struct bpf_ops *bpf_ops;
277 void     bpf_setops(void);
278 
279 void     bpf_ops_handover_enter(struct bpf_ops *);
280 void     bpf_ops_handover_exit(void);
281 
282 void	 bpfilterattach(int);
283 
284 int	 bpf_validate(struct bpf_insn *, int);
285 #endif
286 
287 u_int	 bpf_filter(struct bpf_insn *, u_char *, u_int, u_int);
288 
289 /*
290  * Number of scratch memory words (for BPF_LD|BPF_MEM and BPF_ST).
291  */
292 #define BPF_MEMWORDS 16
293 
294 #endif /* !_NET_BPF_H_ */
295