xref: /dragonfly/sys/net/bpf.h (revision 49781055)
1 /*
2  * Copyright (c) 1990, 1991, 1993
3  *	The Regents of the University of California.  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	8.1 (Berkeley) 6/10/93
39  *	@(#)bpf.h	1.34 (LBL)     6/16/96
40  *
41  * $FreeBSD: src/sys/net/bpf.h,v 1.21.2.4 2002/07/05 14:40:00 fenner Exp $
42  * $DragonFly: src/sys/net/bpf.h,v 1.9 2005/04/20 10:22:44 hmp Exp $
43  */
44 
45 #ifndef _NET_BPF_H_
46 #define _NET_BPF_H_
47 
48 /* BSD style release date */
49 #define	BPF_RELEASE 199606
50 
51 typedef	int32_t	  bpf_int32;
52 typedef	u_int32_t bpf_u_int32;
53 
54 /*
55  * Alignment macros.  BPF_WORDALIGN rounds up to the next
56  * even multiple of BPF_ALIGNMENT.
57  */
58 #define BPF_ALIGNMENT sizeof(long)
59 #define BPF_WORDALIGN(x) (((x)+(BPF_ALIGNMENT-1))&~(BPF_ALIGNMENT-1))
60 
61 #define BPF_MAXINSNS 512
62 #define BPF_MAXBUFSIZE 0x80000
63 #define BPF_DEFAULTBUFSIZE 4096
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 #define	BIOCGBLEN	_IOR('B',102, u_int)
102 #define	BIOCSBLEN	_IOWR('B',102, u_int)
103 #define	BIOCSETF	_IOW('B',103, struct bpf_program)
104 #define	BIOCFLUSH	_IO('B',104)
105 #define BIOCPROMISC	_IO('B',105)
106 #define	BIOCGDLT	_IOR('B',106, u_int)
107 #define BIOCGETIF	_IOR('B',107, struct ifreq)
108 #define BIOCSETIF	_IOW('B',108, struct ifreq)
109 #define BIOCSRTIMEOUT	_IOW('B',109, struct timeval)
110 #define BIOCGRTIMEOUT	_IOR('B',110, struct timeval)
111 #define BIOCGSTATS	_IOR('B',111, struct bpf_stat)
112 #define BIOCIMMEDIATE	_IOW('B',112, u_int)
113 #define BIOCVERSION	_IOR('B',113, struct bpf_version)
114 #define BIOCGRSIG	_IOR('B',114, u_int)
115 #define BIOCSRSIG	_IOW('B',115, u_int)
116 #define BIOCGHDRCMPLT	_IOR('B',116, u_int)
117 #define BIOCSHDRCMPLT	_IOW('B',117, u_int)
118 #define BIOCGSEESENT	_IOR('B',118, u_int)
119 #define BIOCSSEESENT	_IOW('B',119, u_int)
120 #define	BIOCSDLT	_IOW('B',120, u_int)
121 #define	BIOCGDLTLIST	_IOWR('B',121, struct bpf_dltlist)
122 
123 /*
124  * Structure prepended to each packet.
125  */
126 struct bpf_hdr {
127 	struct timeval	bh_tstamp;	/* time stamp */
128 	bpf_u_int32	bh_caplen;	/* length of captured portion */
129 	bpf_u_int32	bh_datalen;	/* original length of packet */
130 	u_short		bh_hdrlen;	/* length of bpf header (this struct
131 					   plus alignment padding) */
132 };
133 /*
134  * Because the structure above is not a multiple of 4 bytes, some compilers
135  * will insist on inserting padding; hence, sizeof(struct bpf_hdr) won't work.
136  * Only the kernel needs to know about it; applications use bh_hdrlen.
137  */
138 #ifdef _KERNEL
139 #define	SIZEOF_BPF_HDR	(sizeof(struct bpf_hdr) <= 20 ? 18 : \
140     sizeof(struct bpf_hdr))
141 #endif
142 
143 /*
144  * Data-link level type codes.
145  */
146 #define DLT_NULL	0	/* no link-layer encapsulation */
147 #define DLT_EN10MB	1	/* Ethernet (10Mb) */
148 #define DLT_EN3MB	2	/* Experimental Ethernet (3Mb) */
149 #define DLT_AX25	3	/* Amateur Radio AX.25 */
150 #define DLT_PRONET	4	/* Proteon ProNET Token Ring */
151 #define DLT_CHAOS	5	/* Chaos */
152 #define DLT_IEEE802	6	/* IEEE 802 Networks */
153 #define DLT_ARCNET	7	/* ARCNET */
154 #define DLT_SLIP	8	/* Serial Line IP */
155 #define DLT_PPP		9	/* Point-to-point Protocol */
156 #define DLT_FDDI	10	/* FDDI */
157 #define DLT_ATM_RFC1483	11	/* LLC/SNAP encapsulated atm */
158 #define DLT_RAW		12	/* raw IP */
159 
160 /*
161  * These are values from BSD/OS's "bpf.h".
162  * These are not the same as the values from the traditional libpcap
163  * "bpf.h"; however, these values shouldn't be generated by any
164  * OS other than BSD/OS, so the correct values to use here are the
165  * BSD/OS values.
166  *
167  * Platforms that have already assigned these values to other
168  * DLT_ codes, however, should give these codes the values
169  * from that platform, so that programs that use these codes will
170  * continue to compile - even though they won't correctly read
171  * files of these types.
172  */
173 #define DLT_SLIP_BSDOS	15	/* BSD/OS Serial Line IP */
174 #define DLT_PPP_BSDOS	16	/* BSD/OS Point-to-point Protocol */
175 
176 #define DLT_ATM_CLIP	19	/* Linux Classical-IP over ATM */
177 
178 /*
179  * These values are defined by NetBSD; other platforms should refrain from
180  * using them for other purposes, so that NetBSD savefiles with link
181  * types of 50 or 51 can be read as this type on all platforms.
182  */
183 #define DLT_PPP_SERIAL	50	/* PPP over serial with HDLC encapsulation */
184 #define DLT_PPP_ETHER	51	/* PPP over Ethernet */
185 
186 /*
187  * This value was defined by libpcap 0.5; platforms that have defined
188  * it with a different value should define it here with that value -
189  * a link type of 104 in a save file will be mapped to DLT_C_HDLC,
190  * whatever value that happens to be, so programs will correctly
191  * handle files with that link type regardless of the value of
192  * DLT_C_HDLC.
193  *
194  * The name DLT_C_HDLC was used by BSD/OS; we use that name for source
195  * compatibility with programs written for BSD/OS.
196  *
197  * libpcap 0.5 defined it as DLT_CHDLC; we define DLT_CHDLC as well,
198  * for source compatibility with programs written for libpcap 0.5.
199  */
200 #define DLT_C_HDLC	104	/* Cisco HDLC */
201 #define DLT_CHDLC	DLT_C_HDLC
202 
203 #define DLT_IEEE802_11	105	/* IEEE 802.11 wireless */
204 
205 /*
206  * Values between 106 and 107 are used in capture file headers as
207  * link-layer types corresponding to DLT_ types that might differ
208  * between platforms; don't use those values for new DLT_ new types.
209  */
210 
211 /*
212  * OpenBSD DLT_LOOP, for loopback devices; it's like DLT_NULL, except
213  * that the AF_ type in the link-layer header is in network byte order.
214  *
215  * OpenBSD defines it as 12, but that collides with DLT_RAW, so we
216  * define it as 108 here.  If OpenBSD picks up this file, it should
217  * define DLT_LOOP as 12 in its version, as per the comment above -
218  * and should not use 108 as a DLT_ value.
219  */
220 #define DLT_LOOP	108
221 
222 /*
223  * Values between 109 and 112 are used in capture file headers as
224  * link-layer types corresponding to DLT_ types that might differ
225  * between platforms; don't use those values for new DLT_ new types.
226  */
227 
228 /*
229  * This is for Linux cooked sockets.
230  */
231 #define DLT_LINUX_SLL	113
232 
233 /*
234  * Apple LocalTalk hardware.
235  */
236 #define DLT_LTALK	114
237 
238 /*
239  * Acorn Econet.
240  */
241 #define DLT_ECONET	115
242 
243 /*
244  * Reserved for use with OpenBSD ipfilter.
245  */
246 #define DLT_IPFILTER	116
247 
248 /*
249  * Reserved for use in capture-file headers as a link-layer type
250  * corresponding to OpenBSD DLT_PFLOG; DLT_PFLOG is 17 in OpenBSD,
251  * but that's DLT_LANE8023 in SuSE 6.3, so we can't use 17 for it
252  * in capture-file headers.
253  */
254 #define DLT_PFLOG	117
255 
256 /*
257  * Registered for Cisco-internal use.
258  */
259 #define DLT_CISCO_IOS	118
260 
261 /*
262  * Reserved for 802.11 cards using the Prism II chips, with a link-layer
263  * header including Prism monitor mode information plus an 802.11
264  * header.
265  */
266 #define DLT_PRISM_HEADER	119
267 
268 /*
269  * Reserved for Aironet 802.11 cards, with an Aironet link-layer header
270  * (see Doug Ambrisko's FreeBSD patches).
271  */
272 #define DLT_AIRONET_HEADER	120
273 
274 /*
275  * Reserved for use by OpenBSD's pfsync device.
276  */
277 #define	DLT_PFSYNC	121
278 
279 /*
280  * The instruction encodings.
281  */
282 /* instruction classes */
283 #define BPF_CLASS(code) ((code) & 0x07)
284 #define		BPF_LD		0x00
285 #define		BPF_LDX		0x01
286 #define		BPF_ST		0x02
287 #define		BPF_STX		0x03
288 #define		BPF_ALU		0x04
289 #define		BPF_JMP		0x05
290 #define		BPF_RET		0x06
291 #define		BPF_MISC	0x07
292 
293 /* ld/ldx fields */
294 #define BPF_SIZE(code)	((code) & 0x18)
295 #define		BPF_W		0x00
296 #define		BPF_H		0x08
297 #define		BPF_B		0x10
298 #define BPF_MODE(code)	((code) & 0xe0)
299 #define		BPF_IMM		0x00
300 #define		BPF_ABS		0x20
301 #define		BPF_IND		0x40
302 #define		BPF_MEM		0x60
303 #define		BPF_LEN		0x80
304 #define		BPF_MSH		0xa0
305 
306 /* alu/jmp fields */
307 #define BPF_OP(code)	((code) & 0xf0)
308 #define		BPF_ADD		0x00
309 #define		BPF_SUB		0x10
310 #define		BPF_MUL		0x20
311 #define		BPF_DIV		0x30
312 #define		BPF_OR		0x40
313 #define		BPF_AND		0x50
314 #define		BPF_LSH		0x60
315 #define		BPF_RSH		0x70
316 #define		BPF_NEG		0x80
317 #define		BPF_JA		0x00
318 #define		BPF_JEQ		0x10
319 #define		BPF_JGT		0x20
320 #define		BPF_JGE		0x30
321 #define		BPF_JSET	0x40
322 #define BPF_SRC(code)	((code) & 0x08)
323 #define		BPF_K		0x00
324 #define		BPF_X		0x08
325 
326 /* ret - BPF_K and BPF_X also apply */
327 #define BPF_RVAL(code)	((code) & 0x18)
328 #define		BPF_A		0x10
329 
330 /* misc */
331 #define BPF_MISCOP(code) ((code) & 0xf8)
332 #define		BPF_TAX		0x00
333 #define		BPF_TXA		0x80
334 
335 /*
336  * The instruction data structure.
337  */
338 struct bpf_insn {
339 	u_short		code;
340 	u_char		jt;
341 	u_char		jf;
342 	bpf_u_int32	k;
343 };
344 
345 /*
346  * Macros for insn array initializers.
347  */
348 #define BPF_STMT(code, k) { (u_short)(code), 0, 0, k }
349 #define BPF_JUMP(code, k, jt, jf) { (u_short)(code), jt, jf, k }
350 
351 /*
352  * Structure to retrieve available DLTs for the interface.
353  */
354 struct bpf_dltlist {
355 	u_int	bfl_len;	/* number of bfd_list array */
356 	u_int	*bfl_list;	/* array of DLTs */
357 };
358 
359 #ifdef _KERNEL
360 struct bpf_if;
361 
362 int	 bpf_validate(const struct bpf_insn *, int);
363 void	 bpf_tap(struct bpf_if *, u_char *, u_int);
364 void	 bpf_mtap(struct bpf_if *, struct mbuf *);
365 void	 bpf_mtap_family(struct bpf_if *, struct mbuf *m, __uint8_t family);
366 void	 bpf_ptap(struct bpf_if *, struct mbuf *, const void *, u_int);
367 void	 bpfattach(struct ifnet *, u_int, u_int);
368 void	 bpfattach_dlt(struct ifnet *, u_int, u_int, struct bpf_if **);
369 void	 bpfdetach(struct ifnet *);
370 
371 void	 bpfilterattach(int);
372 u_int	 bpf_filter(const struct bpf_insn *, u_char *, u_int, u_int);
373 
374 #define	BPF_TAP(_ifp,_pkt,_pktlen) do {				\
375 	if ((_ifp)->if_bpf)					\
376 		bpf_tap((_ifp)->if_bpf, (_pkt), (_pktlen));	\
377 } while (0)
378 #define	BPF_MTAP(_ifp,_m) do {					\
379 	if ((_ifp)->if_bpf)					\
380 		bpf_mtap((_ifp)->if_bpf, (_m));			\
381 } while (0)
382 #endif
383 
384 /*
385  * Number of scratch memory words (for BPF_LD|BPF_MEM and BPF_ST).
386  */
387 #define BPF_MEMWORDS 16
388 
389 #endif
390