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