xref: /freebsd/sys/net/bpf.h (revision 7bd6fde3)
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  * 4. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  *      @(#)bpf.h	8.1 (Berkeley) 6/10/93
35  *	@(#)bpf.h	1.34 (LBL)     6/16/96
36  *
37  * $FreeBSD$
38  */
39 
40 #ifndef _NET_BPF_H_
41 #define _NET_BPF_H_
42 
43 /* BSD style release date */
44 #define	BPF_RELEASE 199606
45 
46 typedef	int32_t	  bpf_int32;
47 typedef	u_int32_t bpf_u_int32;
48 
49 /*
50  * Alignment macros.  BPF_WORDALIGN rounds up to the next
51  * even multiple of BPF_ALIGNMENT.
52  */
53 #define BPF_ALIGNMENT sizeof(long)
54 #define BPF_WORDALIGN(x) (((x)+(BPF_ALIGNMENT-1))&~(BPF_ALIGNMENT-1))
55 
56 #define BPF_MAXINSNS 512
57 #define BPF_MAXBUFSIZE 0x80000
58 #define BPF_MINBUFSIZE 32
59 
60 /*
61  *  Structure for BIOCSETF.
62  */
63 struct bpf_program {
64 	u_int bf_len;
65 	struct bpf_insn *bf_insns;
66 };
67 
68 /*
69  * Struct returned by BIOCGSTATS.
70  */
71 struct bpf_stat {
72 	u_int bs_recv;		/* number of packets received */
73 	u_int bs_drop;		/* number of packets dropped */
74 };
75 
76 /*
77  * Struct return by BIOCVERSION.  This represents the version number of
78  * the filter language described by the instruction encodings below.
79  * bpf understands a program iff kernel_major == filter_major &&
80  * kernel_minor >= filter_minor, that is, if the value returned by the
81  * running kernel has the same major number and a minor number equal
82  * equal to or less than the filter being downloaded.  Otherwise, the
83  * results are undefined, meaning an error may be returned or packets
84  * may be accepted haphazardly.
85  * It has nothing to do with the source code version.
86  */
87 struct bpf_version {
88 	u_short bv_major;
89 	u_short bv_minor;
90 };
91 /* Current version number of filter architecture. */
92 #define BPF_MAJOR_VERSION 1
93 #define BPF_MINOR_VERSION 1
94 
95 #define	BIOCGBLEN	_IOR('B',102, u_int)
96 #define	BIOCSBLEN	_IOWR('B',102, u_int)
97 #define	BIOCSETF	_IOW('B',103, struct bpf_program)
98 #define	BIOCFLUSH	_IO('B',104)
99 #define BIOCPROMISC	_IO('B',105)
100 #define	BIOCGDLT	_IOR('B',106, u_int)
101 #define BIOCGETIF	_IOR('B',107, struct ifreq)
102 #define BIOCSETIF	_IOW('B',108, struct ifreq)
103 #define BIOCSRTIMEOUT	_IOW('B',109, struct timeval)
104 #define BIOCGRTIMEOUT	_IOR('B',110, struct timeval)
105 #define BIOCGSTATS	_IOR('B',111, struct bpf_stat)
106 #define BIOCIMMEDIATE	_IOW('B',112, u_int)
107 #define BIOCVERSION	_IOR('B',113, struct bpf_version)
108 #define BIOCGRSIG	_IOR('B',114, u_int)
109 #define BIOCSRSIG	_IOW('B',115, u_int)
110 #define BIOCGHDRCMPLT	_IOR('B',116, u_int)
111 #define BIOCSHDRCMPLT	_IOW('B',117, u_int)
112 #define BIOCGDIRECTION	_IOR('B',118, u_int)
113 #define BIOCSDIRECTION	_IOW('B',119, u_int)
114 #define	BIOCSDLT	_IOW('B',120, u_int)
115 #define	BIOCGDLTLIST	_IOWR('B',121, struct bpf_dltlist)
116 #define	BIOCLOCK	_IO('B', 122)
117 #define	BIOCSETWF	_IOW('B',123, struct bpf_program)
118 #define	BIOCFEEDBACK	_IOW('B',124, u_int)
119 
120 /* Obsolete */
121 #define	BIOCGSEESENT	BIOCGDIRECTION
122 #define	BIOCSSEESENT	BIOCSDIRECTION
123 
124 /* Packet directions */
125 enum bpf_direction {
126 	BPF_D_IN,	/* See incoming packets */
127 	BPF_D_INOUT,	/* See incoming and outgoing packets */
128 	BPF_D_OUT	/* See outgoing packets */
129 };
130 
131 /*
132  * Structure prepended to each packet.
133  */
134 struct bpf_hdr {
135 	struct timeval	bh_tstamp;	/* time stamp */
136 	bpf_u_int32	bh_caplen;	/* length of captured portion */
137 	bpf_u_int32	bh_datalen;	/* original length of packet */
138 	u_short		bh_hdrlen;	/* length of bpf header (this struct
139 					   plus alignment padding) */
140 };
141 /*
142  * Because the structure above is not a multiple of 4 bytes, some compilers
143  * will insist on inserting padding; hence, sizeof(struct bpf_hdr) won't work.
144  * Only the kernel needs to know about it; applications use bh_hdrlen.
145  */
146 #ifdef _KERNEL
147 #define	SIZEOF_BPF_HDR	(sizeof(struct bpf_hdr) <= 20 ? 18 : \
148     sizeof(struct bpf_hdr))
149 #endif
150 
151 /*
152  * Data-link level type codes.
153  */
154 #define DLT_NULL	0	/* BSD loopback encapsulation */
155 #define DLT_EN10MB	1	/* Ethernet (10Mb) */
156 #define DLT_EN3MB	2	/* Experimental Ethernet (3Mb) */
157 #define DLT_AX25	3	/* Amateur Radio AX.25 */
158 #define DLT_PRONET	4	/* Proteon ProNET Token Ring */
159 #define DLT_CHAOS	5	/* Chaos */
160 #define DLT_IEEE802	6	/* IEEE 802 Networks */
161 #define DLT_ARCNET	7	/* ARCNET */
162 #define DLT_SLIP	8	/* Serial Line IP */
163 #define DLT_PPP		9	/* Point-to-point Protocol */
164 #define DLT_FDDI	10	/* FDDI */
165 #define DLT_ATM_RFC1483	11	/* LLC/SNAP encapsulated atm */
166 #define DLT_RAW		12	/* raw IP */
167 
168 /*
169  * These are values from BSD/OS's "bpf.h".
170  * These are not the same as the values from the traditional libpcap
171  * "bpf.h"; however, these values shouldn't be generated by any
172  * OS other than BSD/OS, so the correct values to use here are the
173  * BSD/OS values.
174  *
175  * Platforms that have already assigned these values to other
176  * DLT_ codes, however, should give these codes the values
177  * from that platform, so that programs that use these codes will
178  * continue to compile - even though they won't correctly read
179  * files of these types.
180  */
181 #define DLT_SLIP_BSDOS	15	/* BSD/OS Serial Line IP */
182 #define DLT_PPP_BSDOS	16	/* BSD/OS Point-to-point Protocol */
183 
184 #define DLT_ATM_CLIP	19	/* Linux Classical-IP over ATM */
185 
186 /*
187  * These values are defined by NetBSD; other platforms should refrain from
188  * using them for other purposes, so that NetBSD savefiles with link
189  * types of 50 or 51 can be read as this type on all platforms.
190  */
191 #define DLT_PPP_SERIAL	50	/* PPP over serial with HDLC encapsulation */
192 #define DLT_PPP_ETHER	51	/* PPP over Ethernet */
193 
194 /*
195  * Reserved for the Symantec Enterprise Firewall.
196  */
197 #define DLT_SYMANTEC_FIREWALL	99
198 
199 
200 /*
201  * This value was defined by libpcap 0.5; platforms that have defined
202  * it with a different value should define it here with that value -
203  * a link type of 104 in a save file will be mapped to DLT_C_HDLC,
204  * whatever value that happens to be, so programs will correctly
205  * handle files with that link type regardless of the value of
206  * DLT_C_HDLC.
207  *
208  * The name DLT_C_HDLC was used by BSD/OS; we use that name for source
209  * compatibility with programs written for BSD/OS.
210  *
211  * libpcap 0.5 defined it as DLT_CHDLC; we define DLT_CHDLC as well,
212  * for source compatibility with programs written for libpcap 0.5.
213  */
214 #define DLT_C_HDLC	104	/* Cisco HDLC */
215 #define DLT_CHDLC	DLT_C_HDLC
216 
217 #define DLT_IEEE802_11	105	/* IEEE 802.11 wireless */
218 
219 /*
220  * Values between 106 and 107 are used in capture file headers as
221  * link-layer types corresponding to DLT_ types that might differ
222  * between platforms; don't use those values for new DLT_ new types.
223  */
224 
225 /*
226  * Frame Relay; BSD/OS has a DLT_FR with a value of 11, but that collides
227  * with other values.
228  * DLT_FR and DLT_FRELAY packets start with the Q.922 Frame Relay header
229  * (DLCI, etc.).
230  */
231 #define DLT_FRELAY	107
232 
233 /*
234  * OpenBSD DLT_LOOP, for loopback devices; it's like DLT_NULL, except
235  * that the AF_ type in the link-layer header is in network byte order.
236  *
237  * OpenBSD defines it as 12, but that collides with DLT_RAW, so we
238  * define it as 108 here.  If OpenBSD picks up this file, it should
239  * define DLT_LOOP as 12 in its version, as per the comment above -
240  * and should not use 108 as a DLT_ value.
241  */
242 #define DLT_LOOP	108
243 
244 /*
245  * Values between 109 and 112 are used in capture file headers as
246  * link-layer types corresponding to DLT_ types that might differ
247  * between platforms; don't use those values for new DLT_ new types.
248  */
249 
250 /*
251  * Encapsulated packets for IPsec; DLT_ENC is 13 in OpenBSD, but that's
252  * DLT_SLIP_BSDOS in NetBSD, so we don't use 13 for it in OSes other
253  * than OpenBSD.
254  */
255 #define DLT_ENC	109
256 
257 /*
258  * This is for Linux cooked sockets.
259  */
260 #define DLT_LINUX_SLL	113
261 
262 /*
263  * Apple LocalTalk hardware.
264  */
265 #define DLT_LTALK	114
266 
267 /*
268  * Acorn Econet.
269  */
270 #define DLT_ECONET	115
271 
272 /*
273  * Reserved for use with OpenBSD ipfilter.
274  */
275 #define DLT_IPFILTER	116
276 
277 /*
278  * Reserved for use in capture-file headers as a link-layer type
279  * corresponding to OpenBSD DLT_PFLOG; DLT_PFLOG is 17 in OpenBSD,
280  * but that's DLT_LANE8023 in SuSE 6.3, so we can't use 17 for it
281  * in capture-file headers.
282  */
283 #define DLT_PFLOG	117
284 
285 /*
286  * Registered for Cisco-internal use.
287  */
288 #define DLT_CISCO_IOS	118
289 
290 /*
291  * Reserved for 802.11 cards using the Prism II chips, with a link-layer
292  * header including Prism monitor mode information plus an 802.11
293  * header.
294  */
295 #define DLT_PRISM_HEADER	119
296 
297 /*
298  * Reserved for Aironet 802.11 cards, with an Aironet link-layer header
299  * (see Doug Ambrisko's FreeBSD patches).
300  */
301 #define DLT_AIRONET_HEADER	120
302 
303 /*
304  * Reserved for use by OpenBSD's pfsync device.
305  */
306 #define DLT_PFSYNC	121
307 
308 /*
309  * Reserved for Siemens HiPath HDLC. XXX
310  */
311 #define DLT_HHDLC	121
312 
313 /*
314  * Reserved for RFC 2625 IP-over-Fibre Channel.
315  */
316 #define DLT_IP_OVER_FC	122
317 
318 /*
319  * Reserved for Full Frontal ATM on Solaris.
320  */
321 #define DLT_SUNATM	123
322 
323 /*
324  * Reserved as per request from Kent Dahlgren <kent@praesum.com>
325  * for private use.
326  */
327 #define DLT_RIO		124	/* RapidIO */
328 #define DLT_PCI_EXP	125	/* PCI Express */
329 #define DLT_AURORA	126	/* Xilinx Aurora link layer */
330 
331 /*
332  * BSD header for 802.11 plus a number of bits of link-layer information
333  * including radio information.
334  */
335 #ifndef DLT_IEEE802_11_RADIO
336 #define DLT_IEEE802_11_RADIO	127
337 #endif
338 
339 /*
340  * Reserved for TZSP encapsulation.
341  */
342 #define DLT_TZSP		128	/* Tazmen Sniffer Protocol */
343 
344 /*
345  * Reserved for Linux ARCNET.
346  */
347 #define DLT_ARCNET_LINUX	129
348 
349 /*
350  * Juniper-private data link types.
351  */
352 #define DLT_JUNIPER_MLPPP	130
353 #define DLT_JUNIPER_MLFR	131
354 #define DLT_JUNIPER_ES		132
355 #define DLT_JUNIPER_GGSN	133
356 #define DLT_JUNIPER_MFR		134
357 #define DLT_JUNIPER_ATM2	135
358 #define DLT_JUNIPER_SERVICES	136
359 #define DLT_JUNIPER_ATM1	137
360 
361 /*
362  * Apple IP-over-IEEE 1394, as per a request from Dieter Siegmund
363  * <dieter@apple.com>.  The header that's presented is an Ethernet-like
364  * header:
365  *
366  *	#define FIREWIRE_EUI64_LEN	8
367  *	struct firewire_header {
368  *		u_char  firewire_dhost[FIREWIRE_EUI64_LEN];
369  *		u_char  firewire_shost[FIREWIRE_EUI64_LEN];
370  *		u_short firewire_type;
371  *	};
372  *
373  * with "firewire_type" being an Ethernet type value, rather than,
374  * for example, raw GASP frames being handed up.
375  */
376 #define DLT_APPLE_IP_OVER_IEEE1394	138
377 
378 /*
379  * Various SS7 encapsulations, as per a request from Jeff Morriss
380  * <jeff.morriss[AT]ulticom.com> and subsequent discussions.
381  */
382 #define DLT_MTP2_WITH_PHDR	139	/* pseudo-header with various info, followed by MTP2 */
383 #define DLT_MTP2		140	/* MTP2, without pseudo-header */
384 #define DLT_MTP3		141	/* MTP3, without pseudo-header or MTP2 */
385 #define DLT_SCCP		142	/* SCCP, without pseudo-header or MTP2 or MTP3 */
386 
387 /*
388  * Reserved for DOCSIS.
389  */
390 #define DLT_DOCSIS	143
391 
392 /*
393  * Reserved for Linux IrDA.
394  */
395 #define DLT_LINUX_IRDA	144
396 
397 /*
398  * Reserved for IBM SP switch and IBM Next Federation switch.
399  */
400 #define DLT_IBM_SP	145
401 #define DLT_IBM_SN	146
402 
403 /*
404  * Reserved for private use.  If you have some link-layer header type
405  * that you want to use within your organization, with the capture files
406  * using that link-layer header type not ever be sent outside your
407  * organization, you can use these values.
408  *
409  * No libpcap release will use these for any purpose, nor will any
410  * tcpdump release use them, either.
411  *
412  * Do *NOT* use these in capture files that you expect anybody not using
413  * your private versions of capture-file-reading tools to read; in
414  * particular, do *NOT* use them in products, otherwise you may find that
415  * people won't be able to use tcpdump, or snort, or Ethereal, or... to
416  * read capture files from your firewall/intrusion detection/traffic
417  * monitoring/etc. appliance, or whatever product uses that DLT_ value,
418  * and you may also find that the developers of those applications will
419  * not accept patches to let them read those files.
420  *
421  * Also, do not use them if somebody might send you a capture using them
422  * for *their* private type and tools using them for *your* private type
423  * would have to read them.
424  *
425  * Instead, ask "tcpdump-workers@tcpdump.org" for a new DLT_ value,
426  * as per the comment above, and use the type you're given.
427  */
428 #define DLT_USER0		147
429 #define DLT_USER1		148
430 #define DLT_USER2		149
431 #define DLT_USER3		150
432 #define DLT_USER4		151
433 #define DLT_USER5		152
434 #define DLT_USER6		153
435 #define DLT_USER7		154
436 #define DLT_USER8		155
437 #define DLT_USER9		156
438 #define DLT_USER10		157
439 #define DLT_USER11		158
440 #define DLT_USER12		159
441 #define DLT_USER13		160
442 #define DLT_USER14		161
443 #define DLT_USER15		162
444 
445 /*
446  * For future use with 802.11 captures - defined by AbsoluteValue
447  * Systems to store a number of bits of link-layer information
448  * including radio information:
449  *
450  *	http://www.shaftnet.org/~pizza/software/capturefrm.txt
451  *
452  * but it might be used by some non-AVS drivers now or in the
453  * future.
454  */
455 #define DLT_IEEE802_11_RADIO_AVS 163	/* 802.11 plus AVS radio header */
456 
457 /*
458  * Juniper-private data link type, as per request from
459  * Hannes Gredler <hannes@juniper.net>.  The DLT_s are used
460  * for passing on chassis-internal metainformation such as
461  * QOS profiles, etc..
462  */
463 #define DLT_JUNIPER_MONITOR     164
464 
465 /*
466  * Reserved for BACnet MS/TP.
467  */
468 #define DLT_BACNET_MS_TP	165
469 
470 /*
471  * Another PPP variant as per request from Karsten Keil <kkeil@suse.de>.
472  *
473  * This is used in some OSes to allow a kernel socket filter to distinguish
474  * between incoming and outgoing packets, on a socket intended to
475  * supply pppd with outgoing packets so it can do dial-on-demand and
476  * hangup-on-lack-of-demand; incoming packets are filtered out so they
477  * don't cause pppd to hold the connection up (you don't want random
478  * input packets such as port scans, packets from old lost connections,
479  * etc. to force the connection to stay up).
480  *
481  * The first byte of the PPP header (0xff03) is modified to accomodate
482  * the direction - 0x00 = IN, 0x01 = OUT.
483  */
484 #define DLT_PPP_PPPD		166
485 
486 /*
487  * Names for backwards compatibility with older versions of some PPP
488  * software; new software should use DLT_PPP_PPPD.
489  */
490 #define DLT_PPP_WITH_DIRECTION	DLT_PPP_PPPD
491 #define DLT_LINUX_PPP_WITHDIRECTION	DLT_PPP_PPPD
492 
493 /*
494  * Juniper-private data link type, as per request from
495  * Hannes Gredler <hannes@juniper.net>.  The DLT_s are used
496  * for passing on chassis-internal metainformation such as
497  * QOS profiles, cookies, etc..
498  */
499 #define DLT_JUNIPER_PPPOE       167
500 #define DLT_JUNIPER_PPPOE_ATM   168
501 
502 #define DLT_GPRS_LLC		169	/* GPRS LLC */
503 #define DLT_GPF_T		170	/* GPF-T (ITU-T G.7041/Y.1303) */
504 #define DLT_GPF_F		171	/* GPF-F (ITU-T G.7041/Y.1303) */
505 
506 /*
507  * Requested by Oolan Zimmer <oz@gcom.com> for use in Gcom's T1/E1 line
508  * monitoring equipment.
509  */
510 #define DLT_GCOM_T1E1		172
511 #define DLT_GCOM_SERIAL		173
512 
513 /*
514  * Juniper-private data link type, as per request from
515  * Hannes Gredler <hannes@juniper.net>.  The DLT_ is used
516  * for internal communication to Physical Interface Cards (PIC)
517  */
518 #define DLT_JUNIPER_PIC_PEER    174
519 
520 /*
521  * Link types requested by Gregor Maier <gregor@endace.com> of Endace
522  * Measurement Systems.  They add an ERF header (see
523  * http://www.endace.com/support/EndaceRecordFormat.pdf) in front of
524  * the link-layer header.
525  */
526 #define DLT_ERF_ETH		175	/* Ethernet */
527 #define DLT_ERF_POS		176	/* Packet-over-SONET */
528 
529 /*
530  * Requested by Daniele Orlandi <daniele@orlandi.com> for raw LAPD
531  * for vISDN (http://www.orlandi.com/visdn/).  Its link-layer header
532  * includes additional information before the LAPD header, so it's
533  * not necessarily a generic LAPD header.
534  */
535 #define DLT_LINUX_LAPD		177
536 
537 /*
538  * Juniper-private data link type, as per request from
539  * Hannes Gredler <hannes@juniper.net>.
540  * The DLT_ are used for prepending meta-information
541  * like interface index, interface name
542  * before standard Ethernet, PPP, Frelay & C-HDLC Frames
543  */
544 #define DLT_JUNIPER_ETHER       178
545 #define DLT_JUNIPER_PPP         179
546 #define DLT_JUNIPER_FRELAY      180
547 #define DLT_JUNIPER_CHDLC       181
548 
549 /*
550  * The instruction encodings.
551  */
552 /* instruction classes */
553 #define BPF_CLASS(code) ((code) & 0x07)
554 #define		BPF_LD		0x00
555 #define		BPF_LDX		0x01
556 #define		BPF_ST		0x02
557 #define		BPF_STX		0x03
558 #define		BPF_ALU		0x04
559 #define		BPF_JMP		0x05
560 #define		BPF_RET		0x06
561 #define		BPF_MISC	0x07
562 
563 /* ld/ldx fields */
564 #define BPF_SIZE(code)	((code) & 0x18)
565 #define		BPF_W		0x00
566 #define		BPF_H		0x08
567 #define		BPF_B		0x10
568 #define BPF_MODE(code)	((code) & 0xe0)
569 #define		BPF_IMM 	0x00
570 #define		BPF_ABS		0x20
571 #define		BPF_IND		0x40
572 #define		BPF_MEM		0x60
573 #define		BPF_LEN		0x80
574 #define		BPF_MSH		0xa0
575 
576 /* alu/jmp fields */
577 #define BPF_OP(code)	((code) & 0xf0)
578 #define		BPF_ADD		0x00
579 #define		BPF_SUB		0x10
580 #define		BPF_MUL		0x20
581 #define		BPF_DIV		0x30
582 #define		BPF_OR		0x40
583 #define		BPF_AND		0x50
584 #define		BPF_LSH		0x60
585 #define		BPF_RSH		0x70
586 #define		BPF_NEG		0x80
587 #define		BPF_JA		0x00
588 #define		BPF_JEQ		0x10
589 #define		BPF_JGT		0x20
590 #define		BPF_JGE		0x30
591 #define		BPF_JSET	0x40
592 #define BPF_SRC(code)	((code) & 0x08)
593 #define		BPF_K		0x00
594 #define		BPF_X		0x08
595 
596 /* ret - BPF_K and BPF_X also apply */
597 #define BPF_RVAL(code)	((code) & 0x18)
598 #define		BPF_A		0x10
599 
600 /* misc */
601 #define BPF_MISCOP(code) ((code) & 0xf8)
602 #define		BPF_TAX		0x00
603 #define		BPF_TXA		0x80
604 
605 /*
606  * The instruction data structure.
607  */
608 struct bpf_insn {
609 	u_short		code;
610 	u_char		jt;
611 	u_char		jf;
612 	bpf_u_int32	k;
613 };
614 
615 /*
616  * Macros for insn array initializers.
617  */
618 #define BPF_STMT(code, k) { (u_short)(code), 0, 0, k }
619 #define BPF_JUMP(code, k, jt, jf) { (u_short)(code), jt, jf, k }
620 
621 /*
622  * Structure to retrieve available DLTs for the interface.
623  */
624 struct bpf_dltlist {
625 	u_int	bfl_len;	/* number of bfd_list array */
626 	u_int	*bfl_list;	/* array of DLTs */
627 };
628 
629 #ifdef _KERNEL
630 /*
631  * Descriptor associated with each attached hardware interface.
632  */
633 struct bpf_if {
634 	LIST_ENTRY(bpf_if)	bif_next;	/* list of all interfaces */
635 	LIST_HEAD(, bpf_d)	bif_dlist;	/* descriptor list */
636 	u_int bif_dlt;				/* link layer type */
637 	u_int bif_hdrlen;		/* length of header (with padding) */
638 	struct ifnet *bif_ifp;		/* corresponding interface */
639 	struct mtx	bif_mtx;	/* mutex for interface */
640 };
641 
642 int	 bpf_validate(const struct bpf_insn *, int);
643 void	 bpf_tap(struct bpf_if *, u_char *, u_int);
644 void	 bpf_mtap(struct bpf_if *, struct mbuf *);
645 void	 bpf_mtap2(struct bpf_if *, void *, u_int, struct mbuf *);
646 void	 bpfattach(struct ifnet *, u_int, u_int);
647 void	 bpfattach2(struct ifnet *, u_int, u_int, struct bpf_if **);
648 void	 bpfdetach(struct ifnet *);
649 
650 void	 bpfilterattach(int);
651 u_int	 bpf_filter(const struct bpf_insn *, u_char *, u_int, u_int);
652 
653 static __inline int
654 bpf_peers_present(struct bpf_if *bpf)
655 {
656 
657 	if (!LIST_EMPTY(&bpf->bif_dlist))
658 		return (1);
659 	return (0);
660 }
661 
662 #define	BPF_TAP(_ifp,_pkt,_pktlen) do {				\
663 	if (bpf_peers_present((_ifp)->if_bpf))			\
664 		bpf_tap((_ifp)->if_bpf, (_pkt), (_pktlen));	\
665 } while (0)
666 #define	BPF_MTAP(_ifp,_m) do {					\
667 	if (bpf_peers_present((_ifp)->if_bpf)) {		\
668 		M_ASSERTVALID(_m);				\
669 		bpf_mtap((_ifp)->if_bpf, (_m));			\
670 	}							\
671 } while (0)
672 #define	BPF_MTAP2(_ifp,_data,_dlen,_m) do {			\
673 	if (bpf_peers_present((_ifp)->if_bpf)) {		\
674 		M_ASSERTVALID(_m);				\
675 		bpf_mtap2((_ifp)->if_bpf,(_data),(_dlen),(_m));	\
676 	}							\
677 } while (0)
678 #endif
679 
680 /*
681  * Number of scratch memory words (for BPF_LD|BPF_MEM and BPF_ST).
682  */
683 #define BPF_MEMWORDS 16
684 
685 #endif /* _NET_BPF_H_ */
686