1/* $NetBSD: bpf.h,v 1.74 2019/02/26 10:30:28 msaitoh 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/ioccom.h>
44#include <sys/time.h>
45
46/* BSD style release date */
47#define BPF_RELEASE 199606
48
49/* Date when COP instructions and external memory have been released. */
50#define BPF_COP_EXTMEM_RELEASE 20140624
51
52__BEGIN_DECLS
53
54typedef int bpf_int32;
55typedef u_int bpf_u_int32;
56
57/*
58 * Alignment macros. BPF_WORDALIGN rounds up to the next
59 * even multiple of BPF_ALIGNMENT.
60 */
61#define BPF_ALIGNMENT sizeof(long)
62#define BPF_ALIGNMENT32 sizeof(int)
63
64#define BPF_WORDALIGN(x) (((x)+(BPF_ALIGNMENT-1))&~(BPF_ALIGNMENT-1))
65#define BPF_WORDALIGN32(x) (((x)+(BPF_ALIGNMENT32-1))&~(BPF_ALIGNMENT32-1))
66
67#define BPF_MAXINSNS 512
68#define BPF_DFLTBUFSIZE (1024*1024) /* default static upper limit */
69#define BPF_MAXBUFSIZE (1024*1024*16) /* hard limit on sysctl'able value */
70#define BPF_MINBUFSIZE 32
71
72/*
73 * Structure for BIOCSETF.
74 */
75struct bpf_program {
76 u_int bf_len;
77 struct bpf_insn *bf_insns;
78};
79
80/*
81 * Struct returned by BIOCGSTATS and net.bpf.stats sysctl.
82 */
83struct bpf_stat {
84 uint64_t bs_recv; /* number of packets received */
85 uint64_t bs_drop; /* number of packets dropped */
86 uint64_t bs_capt; /* number of packets captured */
87 uint64_t bs_padding[13];
88};
89
90/*
91 * Struct returned by BIOCGSTATSOLD.
92 */
93struct bpf_stat_old {
94 u_int bs_recv; /* number of packets received */
95 u_int bs_drop; /* number of packets dropped */
96};
97
98/*
99 * Struct return by BIOCVERSION. This represents the version number of
100 * the filter language described by the instruction encodings below.
101 * bpf understands a program iff kernel_major == filter_major &&
102 * kernel_minor >= filter_minor, that is, if the value returned by the
103 * running kernel has the same major number and a minor number equal
104 * equal to or less than the filter being downloaded. Otherwise, the
105 * results are undefined, meaning an error may be returned or packets
106 * may be accepted haphazardly.
107 * It has nothing to do with the source code version.
108 */
109struct bpf_version {
110 u_short bv_major;
111 u_short bv_minor;
112};
113/* Current version number of filter architecture. */
114#define BPF_MAJOR_VERSION 1
115#define BPF_MINOR_VERSION 1
116
117/*
118 * BPF ioctls
119 *
120 * The first set is for compatibility with Sun's pcc style
121 * header files. If your using gcc, we assume that you
122 * have run fixincludes so the latter set should work.
123 */
124#define BIOCGBLEN _IOR('B', 102, u_int)
125#define BIOCSBLEN _IOWR('B', 102, u_int)
126#define BIOCSETF _IOW('B', 103, struct bpf_program)
127#define BIOCFLUSH _IO('B', 104)
128#define BIOCPROMISC _IO('B', 105)
129#define BIOCGDLT _IOR('B', 106, u_int)
130#define BIOCGETIF _IOR('B', 107, struct ifreq)
131#define BIOCSETIF _IOW('B', 108, struct ifreq)
132#ifdef COMPAT_50
133#include <compat/sys/time.h>
134#define BIOCSORTIMEOUT _IOW('B', 109, struct timeval50)
135#define BIOCGORTIMEOUT _IOR('B', 110, struct timeval50)
136#endif
137#define BIOCGSTATS _IOR('B', 111, struct bpf_stat)
138#define BIOCGSTATSOLD _IOR('B', 111, struct bpf_stat_old)
139#define BIOCIMMEDIATE _IOW('B', 112, u_int)
140#define BIOCVERSION _IOR('B', 113, struct bpf_version)
141#define BIOCSTCPF _IOW('B', 114, struct bpf_program)
142#define BIOCSUDPF _IOW('B', 115, struct bpf_program)
143#define BIOCGHDRCMPLT _IOR('B', 116, u_int)
144#define BIOCSHDRCMPLT _IOW('B', 117, u_int)
145#define BIOCSDLT _IOW('B', 118, u_int)
146#define BIOCGDLTLIST _IOWR('B', 119, struct bpf_dltlist)
147#define BIOCGDIRECTION _IOR('B', 120, u_int)
148#define BIOCSDIRECTION _IOW('B', 121, u_int)
149#define BIOCSRTIMEOUT _IOW('B', 122, struct timeval)
150#define BIOCGRTIMEOUT _IOR('B', 123, struct timeval)
151#define BIOCGFEEDBACK _IOR('B', 124, u_int)
152#define BIOCSFEEDBACK _IOW('B', 125, u_int)
153#define BIOCFEEDBACK BIOCSFEEDBACK /* FreeBSD name */
154
155/* Obsolete */
156#define BIOCGSEESENT BIOCGDIRECTION
157#define BIOCSSEESENT BIOCSDIRECTION
158
159/*
160 * Packet directions.
161 * BPF_D_IN = 0, BPF_D_INOUT =1 for backward compatibility of BIOC[GS]SEESENT.
162 */
163#define BPF_D_IN 0 /* See incoming packets */
164#define BPF_D_INOUT 1 /* See incoming and outgoing packets */
165#define BPF_D_OUT 2 /* See outgoing packets */
166
167/*
168 * Structure prepended to each packet. This is "wire" format, so we
169 * cannot change it unfortunately to 64 bit times on 32 bit systems [yet].
170 */
171struct bpf_timeval {
172 long tv_sec;
173 long tv_usec;
174};
175
176struct bpf_timeval32 {
177 int32_t tv_sec;
178 int32_t tv_usec;
179};
180
181struct bpf_hdr {
182 struct bpf_timeval bh_tstamp; /* time stamp */
183 uint32_t bh_caplen; /* length of captured portion */
184 uint32_t bh_datalen; /* original length of packet */
185 uint16_t bh_hdrlen; /* length of bpf header (this struct
186 plus alignment padding) */
187};
188
189struct bpf_hdr32 {
190 struct bpf_timeval32 bh_tstamp; /* time stamp */
191 uint32_t bh_caplen; /* length of captured portion */
192 uint32_t bh_datalen; /* original length of packet */
193 uint16_t bh_hdrlen; /* length of bpf header (this struct
194 plus alignment padding) */
195};
196/*
197 * Because the structure above is not a multiple of 4 bytes, some compilers
198 * will insist on inserting padding; hence, sizeof(struct bpf_hdr) won't work.
199 * Only the kernel needs to know about it; applications use bh_hdrlen.
200 * XXX To save a few bytes on 32-bit machines, we avoid end-of-struct
201 * XXX padding by using the size of the header data elements. This is
202 * XXX fail-safe: on new machines, we just use the 'safe' sizeof.
203 */
204#ifdef _KERNEL
205#if defined(__arm32__) || defined(__i386__) || defined(__m68k__) || \
206 defined(__mips__) || defined(__ns32k__) || defined(__vax__) || \
207 defined(__sh__) || (defined(__sparc__) && !defined(__sparc64__))
208#define SIZEOF_BPF_HDR 18
209#define SIZEOF_BPF_HDR32 18
210#else
211#define SIZEOF_BPF_HDR sizeof(struct bpf_hdr)
212#define SIZEOF_BPF_HDR32 sizeof(struct bpf_hdr32)
213#endif
214#endif
215
216/* Pull in data-link level type codes. */
217#include <net/dlt.h>
218
219/*
220 * The instruction encodings.
221 */
222/* instruction classes */
223#define BPF_CLASS(code) ((code) & 0x07)
224#define BPF_LD 0x00
225#define BPF_LDX 0x01
226#define BPF_ST 0x02
227#define BPF_STX 0x03
228#define BPF_ALU 0x04
229#define BPF_JMP 0x05
230#define BPF_RET 0x06
231#define BPF_MISC 0x07
232
233/* ld/ldx fields */
234#define BPF_SIZE(code) ((code) & 0x18)
235#define BPF_W 0x00
236#define BPF_H 0x08
237#define BPF_B 0x10
238/* 0x18 reserved; used by BSD/OS */
239#define BPF_MODE(code) ((code) & 0xe0)
240#define BPF_IMM 0x00
241#define BPF_ABS 0x20
242#define BPF_IND 0x40
243#define BPF_MEM 0x60
244#define BPF_LEN 0x80
245#define BPF_MSH 0xa0
246/* 0xc0 reserved; used by BSD/OS */
247/* 0xe0 reserved; used by BSD/OS */
248
249/* alu/jmp fields */
250#define BPF_OP(code) ((code) & 0xf0)
251#define BPF_ADD 0x00
252#define BPF_SUB 0x10
253#define BPF_MUL 0x20
254#define BPF_DIV 0x30
255#define BPF_OR 0x40
256#define BPF_AND 0x50
257#define BPF_LSH 0x60
258#define BPF_RSH 0x70
259#define BPF_NEG 0x80
260#define BPF_MOD 0x90
261#define BPF_XOR 0xa0
262/* 0xb0 reserved */
263/* 0xc0 reserved */
264/* 0xd0 reserved */
265/* 0xe0 reserved */
266/* 0xf0 reserved */
267#define BPF_JA 0x00
268#define BPF_JEQ 0x10
269#define BPF_JGT 0x20
270#define BPF_JGE 0x30
271#define BPF_JSET 0x40
272/* 0x50 reserved; used by BSD/OS */
273/* 0x60 reserved */
274/* 0x70 reserved */
275/* 0x80 reserved */
276/* 0x90 reserved */
277/* 0xa0 reserved */
278/* 0xb0 reserved */
279/* 0xc0 reserved */
280/* 0xd0 reserved */
281/* 0xe0 reserved */
282/* 0xf0 reserved */
283#define BPF_SRC(code) ((code) & 0x08)
284#define BPF_K 0x00
285#define BPF_X 0x08
286
287/* ret - BPF_K and BPF_X also apply */
288#define BPF_RVAL(code) ((code) & 0x18)
289#define BPF_A 0x10
290/* 0x18 reserved */
291
292/* misc */
293#define BPF_MISCOP(code) ((code) & 0xf8)
294#define BPF_TAX 0x00
295/* 0x10 reserved */
296/* 0x18 reserved */
297#define BPF_COP 0x20
298/* 0x28 reserved */
299/* 0x30 reserved */
300/* 0x38 reserved */
301#define BPF_COPX 0x40 /* XXX: also used by BSD/OS */
302/* 0x48 reserved */
303/* 0x50 reserved */
304/* 0x58 reserved */
305/* 0x60 reserved */
306/* 0x68 reserved */
307/* 0x70 reserved */
308/* 0x78 reserved */
309#define BPF_TXA 0x80
310/* 0x88 reserved */
311/* 0x90 reserved */
312/* 0x98 reserved */
313/* 0xa0 reserved */
314/* 0xa8 reserved */
315/* 0xb0 reserved */
316/* 0xb8 reserved */
317/* 0xc0 reserved; used by BSD/OS */
318/* 0xc8 reserved */
319/* 0xd0 reserved */
320/* 0xd8 reserved */
321/* 0xe0 reserved */
322/* 0xe8 reserved */
323/* 0xf0 reserved */
324/* 0xf8 reserved */
325
326/*
327 * The instruction data structure.
328 */
329struct bpf_insn {
330 uint16_t code;
331 u_char jt;
332 u_char jf;
333 uint32_t k;
334};
335
336/*
337 * Auxiliary data, for use when interpreting a filter intended for the
338 * Linux kernel when the kernel rejects the filter (requiring us to
339 * run it in userland). It contains VLAN tag information.
340 */
341struct bpf_aux_data {
342 u_short vlan_tag_present;
343 u_short vlan_tag;
344};
345
346/*
347 * Macros for insn array initializers.
348 */
349#define BPF_STMT(code, k) { (uint16_t)(code), 0, 0, k }
350#define BPF_JUMP(code, k, jt, jf) { (uint16_t)(code), jt, jf, k }
351
352/*
353 * Number of scratch memory words (for BPF_LD|BPF_MEM and BPF_ST).
354 */
355#define BPF_MEMWORDS 16
356
357/*
358 * bpf_memword_init_t: bits indicate which words in the external memory
359 * store will be initialised by the caller before BPF program execution.
360 */
361typedef uint32_t bpf_memword_init_t;
362#define BPF_MEMWORD_INIT(k) (UINT32_C(1) << (k))
363
364/* Note: two most significant bits are reserved by bpfjit. */
365__CTASSERT(BPF_MEMWORDS + 2 <= sizeof(bpf_memword_init_t) * NBBY);
366
367#ifdef _KERNEL
368/*
369 * Max number of external memory words (for BPF_LD|BPF_MEM and BPF_ST).
370 */
371#define BPF_MAX_MEMWORDS 30
372
373__CTASSERT(BPF_MAX_MEMWORDS >= BPF_MEMWORDS);
374__CTASSERT(BPF_MAX_MEMWORDS + 2 <= sizeof(bpf_memword_init_t) * NBBY);
375#endif
376
377/*
378 * Structure to retrieve available DLTs for the interface.
379 */
380struct bpf_dltlist {
381 u_int bfl_len; /* number of bfd_list array */
382 u_int *bfl_list; /* array of DLTs */
383};
384
385struct bpf_ctx;
386typedef struct bpf_ctx bpf_ctx_t;
387
388typedef struct bpf_args {
389 const uint8_t * pkt;
390 size_t wirelen;
391 size_t buflen;
392 /*
393 * The following arguments are used only by some kernel
394 * subsystems.
395 * They aren't required for classical bpf filter programs.
396 * For such programs, bpfjit generated code doesn't read
397 * those arguments at all. Note however that bpf interpreter
398 * always needs a pointer to memstore.
399 */
400 uint32_t * mem; /* pointer to external memory store */
401 void * arg; /* auxiliary argument for a copfunc */
402} bpf_args_t;
403
404#if defined(_KERNEL) || defined(__BPF_PRIVATE)
405
406typedef uint32_t (*bpf_copfunc_t)(const bpf_ctx_t *, bpf_args_t *, uint32_t);
407
408struct bpf_ctx {
409 /*
410 * BPF coprocessor functions and the number of them.
411 */
412 const bpf_copfunc_t * copfuncs;
413 size_t nfuncs;
414
415 /*
416 * The number of memory words in the external memory store.
417 * There may be up to BPF_MAX_MEMWORDS words; if zero is set,
418 * then the internal memory store is used which has a fixed
419 * number of words (BPF_MEMWORDS).
420 */
421 size_t extwords;
422
423 /*
424 * The bitmask indicating which words in the external memstore
425 * will be initialised by the caller.
426 */
427 bpf_memword_init_t preinited;
428};
429#endif
430
431#ifdef _KERNEL
432#include <net/bpfjit.h>
433#include <net/if.h>
434
435struct bpf_if;
436
437struct bpf_ops {
438 void (*bpf_attach)(struct ifnet *, u_int, u_int, struct bpf_if **);
439 void (*bpf_detach)(struct ifnet *);
440 void (*bpf_change_type)(struct ifnet *, u_int, u_int);
441
442 void (*bpf_mtap)(struct bpf_if *, struct mbuf *, u_int);
443 void (*bpf_mtap2)(struct bpf_if *, void *, u_int, struct mbuf *,
444 u_int);
445 void (*bpf_mtap_af)(struct bpf_if *, uint32_t, struct mbuf *, u_int);
446 void (*bpf_mtap_sl_in)(struct bpf_if *, u_char *, struct mbuf **);
447 void (*bpf_mtap_sl_out)(struct bpf_if *, u_char *, struct mbuf *);
448
449 void (*bpf_mtap_softint_init)(struct ifnet *);
450 void (*bpf_mtap_softint)(struct ifnet *, struct mbuf *);
451};
452
453extern struct bpf_ops *bpf_ops;
454
455static __inline void
456bpf_attach(struct ifnet *_ifp, u_int _dlt, u_int _hdrlen)
457{
458 bpf_ops->bpf_attach(_ifp, _dlt, _hdrlen, &_ifp->if_bpf);
459}
460
461static __inline void
462bpf_attach2(struct ifnet *_ifp, u_int _dlt, u_int _hdrlen, struct bpf_if **_dp)
463{
464 bpf_ops->bpf_attach(_ifp, _dlt, _hdrlen, _dp);
465}
466
467static __inline void
468bpf_mtap(struct ifnet *_ifp, struct mbuf *_m, u_int _direction)
469{
470 if (_ifp->if_bpf)
471 bpf_ops->bpf_mtap(_ifp->if_bpf, _m, _direction);
472}
473
474static __inline void
475bpf_mtap2(struct bpf_if *_bpf, void *_data, u_int _dlen, struct mbuf *_m,
476 u_int _direction)
477{
478 bpf_ops->bpf_mtap2(_bpf, _data, _dlen, _m, _direction);
479}
480
481static __inline void
482bpf_mtap3(struct bpf_if *_bpf, struct mbuf *_m, u_int _direction)
483{
484 if (_bpf)
485 bpf_ops->bpf_mtap(_bpf, _m, _direction);
486}
487
488static __inline void
489bpf_mtap_af(struct ifnet *_ifp, uint32_t _af, struct mbuf *_m,
490 u_int _direction)
491{
492 if (_ifp->if_bpf)
493 bpf_ops->bpf_mtap_af(_ifp->if_bpf, _af, _m, _direction);
494}
495
496static __inline void
497bpf_change_type(struct ifnet *_ifp, u_int _dlt, u_int _hdrlen)
498{
499 bpf_ops->bpf_change_type(_ifp, _dlt, _hdrlen);
500}
501
502static __inline void
503bpf_detach(struct ifnet *_ifp)
504{
505 bpf_ops->bpf_detach(_ifp);
506}
507
508static __inline void
509bpf_mtap_sl_in(struct ifnet *_ifp, u_char *_hdr, struct mbuf **_m)
510{
511 bpf_ops->bpf_mtap_sl_in(_ifp->if_bpf, _hdr, _m);
512}
513
514static __inline void
515bpf_mtap_sl_out(struct ifnet *_ifp, u_char *_hdr, struct mbuf *_m)
516{
517 if (_ifp->if_bpf)
518 bpf_ops->bpf_mtap_sl_out(_ifp->if_bpf, _hdr, _m);
519}
520
521static __inline void
522bpf_mtap_softint_init(struct ifnet *_ifp)
523{
524
525 bpf_ops->bpf_mtap_softint_init(_ifp);
526}
527
528static __inline void
529bpf_mtap_softint(struct ifnet *_ifp, struct mbuf *_m)
530{
531
532 if (_ifp->if_bpf)
533 bpf_ops->bpf_mtap_softint(_ifp, _m);
534}
535
536void bpf_setops(void);
537
538void bpf_ops_handover_enter(struct bpf_ops *);
539void bpf_ops_handover_exit(void);
540
541void bpfilterattach(int);
542
543bpf_ctx_t *bpf_create(void);
544void bpf_destroy(bpf_ctx_t *);
545
546int bpf_set_cop(bpf_ctx_t *, const bpf_copfunc_t *, size_t);
547int bpf_set_extmem(bpf_ctx_t *, size_t, bpf_memword_init_t);
548u_int bpf_filter_ext(const bpf_ctx_t *, const struct bpf_insn *, bpf_args_t *);
549int bpf_validate_ext(const bpf_ctx_t *, const struct bpf_insn *, int);
550
551bpfjit_func_t bpf_jit_generate(bpf_ctx_t *, void *, size_t);
552void bpf_jit_freecode(bpfjit_func_t);
553
554#endif
555
556int bpf_validate(const struct bpf_insn *, int);
557u_int bpf_filter(const struct bpf_insn *, const u_char *, u_int, u_int);
558
559u_int bpf_filter_with_aux_data(const struct bpf_insn *, const u_char *, u_int, u_int, const struct bpf_aux_data *);
560
561
562__END_DECLS
563
564#endif /* !_NET_BPF_H_ */
565