master
1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
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 8.1 (Berkeley) 6/10/93
37 * @(#)bpf.h 1.34 (LBL) 6/16/96
38 */
39
40#ifndef _NET_BPF_H_
41#define _NET_BPF_H_
42
43#include <sys/_eventhandler.h>
44#include <sys/ck.h>
45#include <net/dlt.h>
46
47/* BSD style release date */
48#define BPF_RELEASE 199606
49
50typedef int32_t bpf_int32;
51typedef u_int32_t bpf_u_int32;
52typedef int64_t bpf_int64;
53typedef u_int64_t bpf_u_int64;
54struct ifnet;
55
56/*
57 * Alignment macros. BPF_WORDALIGN rounds up to the next multiple of
58 * BPF_ALIGNMENT.
59 */
60#define BPF_ALIGNMENT sizeof(long)
61#define BPF_WORDALIGN(x) (((x) + (BPF_ALIGNMENT - 1)) & ~(BPF_ALIGNMENT - 1))
62
63#define BPF_MAXINSNS 512
64#define BPF_MAXBUFSIZE 0x80000
65#define BPF_MINBUFSIZE 32
66
67/*
68 * Structure for BIOCSETF.
69 */
70struct bpf_program {
71 u_int bf_len;
72 struct bpf_insn *bf_insns;
73};
74
75/*
76 * Struct returned by BIOCGSTATS.
77 */
78struct bpf_stat {
79 u_int bs_recv; /* number of packets received */
80 u_int bs_drop; /* number of packets dropped */
81};
82
83/*
84 * Struct return by BIOCVERSION. This represents the version number of
85 * the filter language described by the instruction encodings below.
86 * bpf understands a program iff kernel_major == filter_major &&
87 * kernel_minor >= filter_minor, that is, if the value returned by the
88 * running kernel has the same major number and a minor number equal
89 * equal to or less than the filter being downloaded. Otherwise, the
90 * results are undefined, meaning an error may be returned or packets
91 * may be accepted haphazardly.
92 * It has nothing to do with the source code version.
93 */
94struct bpf_version {
95 u_short bv_major;
96 u_short bv_minor;
97};
98/* Current version number of filter architecture. */
99#define BPF_MAJOR_VERSION 1
100#define BPF_MINOR_VERSION 1
101
102/*
103 * Historically, BPF has supported a single buffering model, first using mbuf
104 * clusters in kernel, and later using malloc(9) buffers in kernel. We now
105 * support multiple buffering modes, which may be queried and set using
106 * BIOCGETBUFMODE and BIOCSETBUFMODE. So as to avoid handling the complexity
107 * of changing modes while sniffing packets, the mode becomes fixed once an
108 * interface has been attached to the BPF descriptor.
109 */
110#define BPF_BUFMODE_BUFFER 1 /* Kernel buffers with read(). */
111#define BPF_BUFMODE_ZBUF 2 /* Zero-copy buffers. */
112
113/*-
114 * Struct used by BIOCSETZBUF, BIOCROTZBUF: describes up to two zero-copy
115 * buffer as used by BPF.
116 */
117struct bpf_zbuf {
118 void *bz_bufa; /* Location of 'a' zero-copy buffer. */
119 void *bz_bufb; /* Location of 'b' zero-copy buffer. */
120 size_t bz_buflen; /* Size of zero-copy buffers. */
121};
122
123#define BIOCGBLEN _IOR('B', 102, u_int)
124#define BIOCSBLEN _IOWR('B', 102, u_int)
125#define BIOCSETF _IOW('B', 103, struct bpf_program)
126#define BIOCFLUSH _IO('B', 104)
127#define BIOCPROMISC _IO('B', 105)
128#define BIOCGDLT _IOR('B', 106, u_int)
129#define BIOCGETIF _IOR('B', 107, struct ifreq)
130#define BIOCSETIF _IOW('B', 108, struct ifreq)
131#define BIOCSRTIMEOUT _IOW('B', 109, struct timeval)
132#define BIOCGRTIMEOUT _IOR('B', 110, struct timeval)
133#define BIOCGSTATS _IOR('B', 111, struct bpf_stat)
134#define BIOCIMMEDIATE _IOW('B', 112, u_int)
135#define BIOCVERSION _IOR('B', 113, struct bpf_version)
136#define BIOCGRSIG _IOR('B', 114, u_int)
137#define BIOCSRSIG _IOW('B', 115, u_int)
138#define BIOCGHDRCMPLT _IOR('B', 116, u_int)
139#define BIOCSHDRCMPLT _IOW('B', 117, u_int)
140#define BIOCGDIRECTION _IOR('B', 118, u_int)
141#define BIOCSDIRECTION _IOW('B', 119, u_int)
142#define BIOCSDLT _IOW('B', 120, u_int)
143#define BIOCGDLTLIST _IOWR('B', 121, struct bpf_dltlist)
144#define BIOCLOCK _IO('B', 122)
145#define BIOCSETWF _IOW('B', 123, struct bpf_program)
146#define BIOCFEEDBACK _IOW('B', 124, u_int)
147#define BIOCGETBUFMODE _IOR('B', 125, u_int)
148#define BIOCSETBUFMODE _IOW('B', 126, u_int)
149#define BIOCGETZMAX _IOR('B', 127, size_t)
150#define BIOCROTZBUF _IOR('B', 128, struct bpf_zbuf)
151#define BIOCSETZBUF _IOW('B', 129, struct bpf_zbuf)
152#define BIOCSETFNR _IOW('B', 130, struct bpf_program)
153#define BIOCGTSTAMP _IOR('B', 131, u_int)
154#define BIOCSTSTAMP _IOW('B', 132, u_int)
155#define BIOCSETVLANPCP _IOW('B', 133, u_int)
156
157/* Obsolete */
158#define BIOCGSEESENT BIOCGDIRECTION
159#define BIOCSSEESENT BIOCSDIRECTION
160
161/* Packet directions */
162enum bpf_direction {
163 BPF_D_IN, /* See incoming packets */
164 BPF_D_INOUT, /* See incoming and outgoing packets */
165 BPF_D_OUT /* See outgoing packets */
166};
167
168/* Time stamping functions */
169#define BPF_T_MICROTIME 0x0000
170#define BPF_T_NANOTIME 0x0001
171#define BPF_T_BINTIME 0x0002
172#define BPF_T_NONE 0x0003
173#define BPF_T_FORMAT_MASK 0x0003
174#define BPF_T_NORMAL 0x0000
175#define BPF_T_FAST 0x0100
176#define BPF_T_MONOTONIC 0x0200
177#define BPF_T_MONOTONIC_FAST (BPF_T_FAST | BPF_T_MONOTONIC)
178#define BPF_T_FLAG_MASK 0x0300
179#define BPF_T_FORMAT(t) ((t) & BPF_T_FORMAT_MASK)
180#define BPF_T_FLAG(t) ((t) & BPF_T_FLAG_MASK)
181#define BPF_T_VALID(t) \
182 ((t) == BPF_T_NONE || (BPF_T_FORMAT(t) != BPF_T_NONE && \
183 ((t) & ~(BPF_T_FORMAT_MASK | BPF_T_FLAG_MASK)) == 0))
184
185#define BPF_T_MICROTIME_FAST (BPF_T_MICROTIME | BPF_T_FAST)
186#define BPF_T_NANOTIME_FAST (BPF_T_NANOTIME | BPF_T_FAST)
187#define BPF_T_BINTIME_FAST (BPF_T_BINTIME | BPF_T_FAST)
188#define BPF_T_MICROTIME_MONOTONIC (BPF_T_MICROTIME | BPF_T_MONOTONIC)
189#define BPF_T_NANOTIME_MONOTONIC (BPF_T_NANOTIME | BPF_T_MONOTONIC)
190#define BPF_T_BINTIME_MONOTONIC (BPF_T_BINTIME | BPF_T_MONOTONIC)
191#define BPF_T_MICROTIME_MONOTONIC_FAST (BPF_T_MICROTIME | BPF_T_MONOTONIC_FAST)
192#define BPF_T_NANOTIME_MONOTONIC_FAST (BPF_T_NANOTIME | BPF_T_MONOTONIC_FAST)
193#define BPF_T_BINTIME_MONOTONIC_FAST (BPF_T_BINTIME | BPF_T_MONOTONIC_FAST)
194
195/*
196 * Structure prepended to each packet.
197 */
198struct bpf_ts {
199 bpf_int64 bt_sec; /* seconds */
200 bpf_u_int64 bt_frac; /* fraction */
201};
202struct bpf_xhdr {
203 struct bpf_ts bh_tstamp; /* time stamp */
204 bpf_u_int32 bh_caplen; /* length of captured portion */
205 bpf_u_int32 bh_datalen; /* original length of packet */
206 u_short bh_hdrlen; /* length of bpf header (this struct
207 plus alignment padding) */
208};
209/* Obsolete */
210struct bpf_hdr {
211 struct timeval bh_tstamp; /* time stamp */
212 bpf_u_int32 bh_caplen; /* length of captured portion */
213 bpf_u_int32 bh_datalen; /* original length of packet */
214 u_short bh_hdrlen; /* length of bpf header (this struct
215 plus alignment padding) */
216};
217#ifdef _KERNEL
218#define MTAG_BPF 0x627066
219#define MTAG_BPF_TIMESTAMP 0
220#endif
221
222/*
223 * When using zero-copy BPF buffers, a shared memory header is present
224 * allowing the kernel BPF implementation and user process to synchronize
225 * without using system calls. This structure defines that header. When
226 * accessing these fields, appropriate atomic operation and memory barriers
227 * are required in order not to see stale or out-of-order data; see bpf(4)
228 * for reference code to access these fields from userspace.
229 *
230 * The layout of this structure is critical, and must not be changed; if must
231 * fit in a single page on all architectures.
232 */
233struct bpf_zbuf_header {
234 volatile u_int bzh_kernel_gen; /* Kernel generation number. */
235 volatile u_int bzh_kernel_len; /* Length of data in the buffer. */
236 volatile u_int bzh_user_gen; /* User generation number. */
237 u_int _bzh_pad[5];
238};
239
240/*
241 * The instruction encodings.
242 *
243 * Please inform tcpdump-workers@lists.tcpdump.org if you use any
244 * of the reserved values, so that we can note that they're used
245 * (and perhaps implement it in the reference BPF implementation
246 * and encourage its implementation elsewhere).
247 */
248
249/*
250 * The upper 8 bits of the opcode aren't used. BSD/OS used 0x8000.
251 */
252
253/* instruction classes */
254#define BPF_CLASS(code) ((code) & 0x07)
255#define BPF_LD 0x00
256#define BPF_LDX 0x01
257#define BPF_ST 0x02
258#define BPF_STX 0x03
259#define BPF_ALU 0x04
260#define BPF_JMP 0x05
261#define BPF_RET 0x06
262#define BPF_MISC 0x07
263
264/* ld/ldx fields */
265#define BPF_SIZE(code) ((code) & 0x18)
266#define BPF_W 0x00
267#define BPF_H 0x08
268#define BPF_B 0x10
269/* 0x18 reserved; used by BSD/OS */
270#define BPF_MODE(code) ((code) & 0xe0)
271#define BPF_IMM 0x00
272#define BPF_ABS 0x20
273#define BPF_IND 0x40
274#define BPF_MEM 0x60
275#define BPF_LEN 0x80
276#define BPF_MSH 0xa0
277/* 0xc0 reserved; used by BSD/OS */
278/* 0xe0 reserved; used by BSD/OS */
279
280/* alu/jmp fields */
281#define BPF_OP(code) ((code) & 0xf0)
282#define BPF_ADD 0x00
283#define BPF_SUB 0x10
284#define BPF_MUL 0x20
285#define BPF_DIV 0x30
286#define BPF_OR 0x40
287#define BPF_AND 0x50
288#define BPF_LSH 0x60
289#define BPF_RSH 0x70
290#define BPF_NEG 0x80
291#define BPF_MOD 0x90
292#define BPF_XOR 0xa0
293/* 0xb0 reserved */
294/* 0xc0 reserved */
295/* 0xd0 reserved */
296/* 0xe0 reserved */
297/* 0xf0 reserved */
298
299#define BPF_JA 0x00
300#define BPF_JEQ 0x10
301#define BPF_JGT 0x20
302#define BPF_JGE 0x30
303#define BPF_JSET 0x40
304/* 0x50 reserved; used on BSD/OS */
305/* 0x60 reserved */
306/* 0x70 reserved */
307/* 0x80 reserved */
308/* 0x90 reserved */
309/* 0xa0 reserved */
310/* 0xb0 reserved */
311/* 0xc0 reserved */
312/* 0xd0 reserved */
313/* 0xe0 reserved */
314/* 0xf0 reserved */
315#define BPF_SRC(code) ((code) & 0x08)
316#define BPF_K 0x00
317#define BPF_X 0x08
318
319/* ret - BPF_K and BPF_X also apply */
320#define BPF_RVAL(code) ((code) & 0x18)
321#define BPF_A 0x10
322/* 0x18 reserved */
323
324/* misc */
325#define BPF_MISCOP(code) ((code) & 0xf8)
326#define BPF_TAX 0x00
327/* 0x08 reserved */
328/* 0x10 reserved */
329/* 0x18 reserved */
330/* #define BPF_COP 0x20 NetBSD "coprocessor" extensions */
331/* 0x28 reserved */
332/* 0x30 reserved */
333/* 0x38 reserved */
334/* #define BPF_COPX 0x40 NetBSD "coprocessor" extensions */
335/* also used on BSD/OS */
336/* 0x48 reserved */
337/* 0x50 reserved */
338/* 0x58 reserved */
339/* 0x60 reserved */
340/* 0x68 reserved */
341/* 0x70 reserved */
342/* 0x78 reserved */
343#define BPF_TXA 0x80
344/* 0x88 reserved */
345/* 0x90 reserved */
346/* 0x98 reserved */
347/* 0xa0 reserved */
348/* 0xa8 reserved */
349/* 0xb0 reserved */
350/* 0xb8 reserved */
351/* 0xc0 reserved; used on BSD/OS */
352/* 0xc8 reserved */
353/* 0xd0 reserved */
354/* 0xd8 reserved */
355/* 0xe0 reserved */
356/* 0xe8 reserved */
357/* 0xf0 reserved */
358/* 0xf8 reserved */
359
360/*
361 * The instruction data structure.
362 */
363struct bpf_insn {
364 u_short code;
365 u_char jt;
366 u_char jf;
367 bpf_u_int32 k;
368};
369
370/*
371 * Macros for insn array initializers.
372 */
373#define BPF_STMT(code, k) { (u_short)(code), 0, 0, k }
374#define BPF_JUMP(code, k, jt, jf) { (u_short)(code), jt, jf, k }
375
376/*
377 * Structure to retrieve available DLTs for the interface.
378 */
379struct bpf_dltlist {
380 u_int bfl_len; /* number of bfd_list array */
381 u_int *bfl_list; /* array of DLTs */
382};
383
384#ifdef _KERNEL
385#ifdef MALLOC_DECLARE
386MALLOC_DECLARE(M_BPF);
387#endif
388#ifdef SYSCTL_DECL
389SYSCTL_DECL(_net_bpf);
390#endif
391
392/*
393 * Rotate the packet buffers in descriptor d. Move the store buffer into the
394 * hold slot, and the free buffer into the store slot. Zero the length of the
395 * new store buffer. Descriptor lock should be held. One must be careful to
396 * not rotate the buffers twice, i.e. if fbuf != NULL.
397 */
398#define ROTATE_BUFFERS(d) do { \
399 (d)->bd_hbuf = (d)->bd_sbuf; \
400 (d)->bd_hlen = (d)->bd_slen; \
401 (d)->bd_sbuf = (d)->bd_fbuf; \
402 (d)->bd_slen = 0; \
403 (d)->bd_fbuf = NULL; \
404 bpf_bufheld(d); \
405} while (0)
406
407/*
408 * Descriptor associated with each attached hardware interface.
409 * Part of this structure is exposed to external callers to speed up
410 * bpf_peers_present() calls.
411 */
412struct bpf_if;
413CK_LIST_HEAD(bpfd_list, bpf_d);
414
415struct bpf_if_ext {
416 CK_LIST_ENTRY(bpf_if) bif_next; /* list of all interfaces */
417 struct bpfd_list bif_dlist; /* descriptor list */
418};
419
420void bpf_bufheld(struct bpf_d *d);
421int bpf_validate(const struct bpf_insn *, int);
422void bpf_tap(struct bpf_if *, u_char *, u_int);
423void bpf_tap_if(struct ifnet *, u_char *, u_int);
424void bpf_mtap(struct bpf_if *, struct mbuf *);
425void bpf_mtap_if(struct ifnet *, struct mbuf *);
426void bpf_mtap2(struct bpf_if *, void *, u_int, struct mbuf *);
427void bpf_mtap2_if(struct ifnet *, void *, u_int, struct mbuf *);
428void bpfattach(struct ifnet *, u_int, u_int);
429void bpfattach2(struct ifnet *, u_int, u_int, struct bpf_if **);
430void bpfdetach(struct ifnet *);
431bool bpf_peers_present_if(struct ifnet *);
432#ifdef VIMAGE
433int bpf_get_bp_params(struct bpf_if *, u_int *, u_int *);
434#endif
435
436void bpfilterattach(int);
437u_int bpf_filter(const struct bpf_insn *, u_char *, u_int, u_int);
438
439static __inline bool
440bpf_peers_present(struct bpf_if *bpf)
441{
442 struct bpf_if_ext *ext;
443
444 ext = (struct bpf_if_ext *)bpf;
445 return (!CK_LIST_EMPTY(&ext->bif_dlist));
446}
447
448#define BPF_TAP(_ifp, _pkt, _pktlen) \
449 bpf_tap_if((_ifp), (_pkt), (_pktlen))
450#define BPF_MTAP(_ifp, _m) \
451 bpf_mtap_if((_ifp), (_m))
452#define BPF_MTAP2(_ifp, _data, _dlen, _m) \
453 bpf_mtap2_if((_ifp), (_data), (_dlen), (_m))
454#endif /* _KERNEL */
455
456/*
457 * Number of scratch memory words (for BPF_LD|BPF_MEM and BPF_ST).
458 */
459#define BPF_MEMWORDS 16
460
461/* BPF attach/detach events */
462typedef void (*bpf_track_fn)(void *, struct ifnet *, int /* dlt */,
463 int /* 1 =>'s attach */);
464EVENTHANDLER_DECLARE(bpf_track, bpf_track_fn);
465
466#endif /* _NET_BPF_H_ */