1/* $OpenBSD: bpf.h,v 1.75 2025/11/16 02:20:08 dlg Exp $ */
2/* $NetBSD: bpf.h,v 1.15 1996/12/13 07:57:33 mikel Exp $ */
3
4/*
5 * Copyright (c) 1990, 1991, 1993
6 * The Regents of the University of California. All rights reserved.
7 *
8 * This code is derived from the Stanford/CMU enet packet filter,
9 * (net/enet.c) distributed as part of 4.3BSD, and code contributed
10 * to Berkeley by Steven McCanne and Van Jacobson both of Lawrence
11 * Berkeley Laboratory.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 * 3. Neither the name of the University nor the names of its contributors
22 * may be used to endorse or promote products derived from this software
23 * without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * SUCH DAMAGE.
36 *
37 * @(#)bpf.h 8.1 (Berkeley) 6/10/93
38 */
39
40#ifndef _NET_BPF_H_
41#define _NET_BPF_H_
42
43/* BSD style release date */
44#define BPF_RELEASE 199606
45
46typedef int32_t bpf_int32;
47typedef u_int32_t bpf_u_int32;
48/*
49 * Alignment macros. BPF_WORDALIGN rounds up to the next even multiple of
50 * BPF_ALIGNMENT (which is at least as much as what a timeval needs).
51 */
52#define BPF_ALIGNMENT sizeof(u_int32_t)
53#define BPF_WORDALIGN(x) (((x) + (BPF_ALIGNMENT - 1)) & ~(BPF_ALIGNMENT - 1))
54
55#define BPF_MAXINSNS 512
56#define BPF_MAXBUFSIZE (2 * 1024 * 1024)
57#define BPF_MINBUFSIZE 32
58
59/*
60 * Structure for BIOCSETF.
61 */
62struct bpf_program {
63 u_int bf_len;
64 struct bpf_insn *bf_insns;
65};
66
67/*
68 * Struct returned by BIOCGSTATS.
69 */
70struct bpf_stat {
71 u_int bs_recv; /* number of packets received */
72 u_int bs_drop; /* number of packets dropped */
73};
74
75/*
76 * Struct return by BIOCVERSION. This represents the version number of
77 * the filter language described by the instruction encodings below.
78 * bpf understands a program iff kernel_major == filter_major &&
79 * kernel_minor >= filter_minor, that is, if the value returned by the
80 * running kernel has the same major number and a minor number equal
81 * equal to or less than the filter being downloaded. Otherwise, the
82 * results are undefined, meaning an error may be returned or packets
83 * may be accepted haphazardly.
84 * It has nothing to do with the source code version.
85 */
86struct bpf_version {
87 u_short bv_major;
88 u_short bv_minor;
89};
90/* Current version number of filter architecture. */
91#define BPF_MAJOR_VERSION 1
92#define BPF_MINOR_VERSION 1
93
94/*
95 * BPF ioctls
96 */
97#define BIOCGBLEN _IOR('B',102, u_int)
98#define BIOCSBLEN _IOWR('B',102, u_int)
99#define BIOCSETF _IOW('B',103, struct bpf_program)
100#define BIOCFLUSH _IO('B',104)
101#define BIOCPROMISC _IO('B',105)
102#define BIOCGDLT _IOR('B',106, u_int)
103#define BIOCGETIF _IOR('B',107, struct ifreq)
104#define BIOCSETIF _IOW('B',108, struct ifreq)
105#define BIOCSRTIMEOUT _IOW('B',109, struct timeval)
106#define BIOCGRTIMEOUT _IOR('B',110, struct timeval)
107#define BIOCGSTATS _IOR('B',111, struct bpf_stat)
108#define BIOCIMMEDIATE _IOW('B',112, u_int)
109#define BIOCVERSION _IOR('B',113, struct bpf_version)
110#define BIOCSRSIG _IOW('B',114, u_int)
111#define BIOCGRSIG _IOR('B',115, u_int)
112#define BIOCGHDRCMPLT _IOR('B',116, u_int)
113#define BIOCSHDRCMPLT _IOW('B',117, u_int)
114#define BIOCLOCK _IO('B',118)
115#define BIOCSETWF _IOW('B',119, struct bpf_program)
116#define BIOCGFILDROP _IOR('B',120, u_int)
117#define BIOCSFILDROP _IOW('B',121, u_int)
118#define BIOCSDLT _IOW('B',122, u_int)
119#define BIOCGDLTLIST _IOWR('B',123, struct bpf_dltlist)
120#define BIOCGDIRFILT _IOR('B',124, u_int)
121#define BIOCSDIRFILT _IOW('B',125, u_int)
122#define BIOCSWTIMEOUT _IOW('B',126, struct timeval)
123#define BIOCGWTIMEOUT _IOR('B',126, struct timeval)
124#define BIOCDWTIMEOUT _IO('B',126)
125#define BIOCSETFNR _IOW('B',127, struct bpf_program)
126
127/*
128 * Direction filters for BIOCSDIRFILT/BIOCGDIRFILT
129 */
130#define BPF_DIRECTION_IN (1 << 0)
131#define BPF_DIRECTION_OUT (1 << 1)
132
133/*
134 * Values for BIOCGFILDROP/BIOCSFILDROP
135 */
136#define BPF_FILDROP_PASS 0 /* capture, pass */
137#define BPF_FILDROP_CAPTURE 1 /* capture, drop */
138#define BPF_FILDROP_DROP 2 /* no capture, drop */
139
140struct bpf_timeval {
141 u_int32_t tv_sec;
142 u_int32_t tv_usec;
143};
144
145/*
146 * Structure prepended to each packet.
147 */
148struct bpf_hdr {
149 struct bpf_timeval bh_tstamp; /* time stamp */
150 u_int32_t bh_caplen; /* length of captured portion */
151 u_int32_t bh_datalen; /* original length of packet */
152 u_int16_t bh_hdrlen; /* length of bpf header (this struct
153 plus alignment padding) */
154 u_int16_t bh_ifidx; /* receive interface index */
155
156 u_int16_t bh_flowid;
157 u_int8_t bh_flags;
158#define BPF_F_PRI_MASK 0x07
159#define BPF_F_FLOWID 0x08
160#define BPF_F_DIR_SHIFT 4
161#define BPF_F_DIR_MASK (0x3 << BPF_F_DIR_SHIFT)
162#define BPF_F_DIR_IN (BPF_DIRECTION_IN << BPF_F_DIR_SHIFT)
163#define BPF_F_DIR_OUT (BPF_DIRECTION_OUT << BPF_F_DIR_SHIFT)
164 u_int8_t bh_drops;
165 u_int16_t bh_csumflags; /* checksum flags */
166};
167
168#ifdef _KERNEL
169#define SIZEOF_BPF_HDR sizeof(struct bpf_hdr)
170#endif
171
172/*
173 * Data-link level type codes.
174 */
175#define DLT_NULL 0 /* no link-layer encapsulation */
176#define DLT_EN10MB 1 /* Ethernet (10Mb) */
177#define DLT_EN3MB 2 /* Experimental Ethernet (3Mb) */
178#define DLT_AX25 3 /* Amateur Radio AX.25 */
179#define DLT_PRONET 4 /* Proteon ProNET Token Ring */
180#define DLT_CHAOS 5 /* Chaos */
181#define DLT_IEEE802 6 /* IEEE 802 Networks */
182#define DLT_ARCNET 7 /* ARCNET */
183#define DLT_SLIP 8 /* Serial Line IP */
184#define DLT_PPP 9 /* Point-to-point Protocol */
185#define DLT_FDDI 10 /* FDDI */
186#define DLT_ATM_RFC1483 11 /* LLC/SNAP encapsulated atm */
187#define DLT_LOOP 12 /* loopback type (af header) */
188#define DLT_ENC 13 /* IPSEC enc type (af header, spi, flags) */
189#define DLT_RAW 14 /* raw IP */
190#define DLT_SLIP_BSDOS 15 /* BSD/OS Serial Line IP */
191#define DLT_PPP_BSDOS 16 /* BSD/OS Point-to-point Protocol */
192#define DLT_PFSYNC 18 /* Packet filter state syncing */
193#define DLT_PPP_SERIAL 50 /* PPP over Serial with HDLC */
194#define DLT_PPP_ETHER 51 /* PPP over Ethernet; session only w/o ether header */
195#define DLT_C_HDLC 104 /* Cisco HDLC */
196#define DLT_IEEE802_11 105 /* IEEE 802.11 wireless */
197#define DLT_PFLOG 117 /* Packet filter logging, by pcap people */
198#define DLT_IEEE802_11_RADIO 127 /* IEEE 802.11 plus WLAN header */
199#define DLT_USER0 147 /* Reserved for private use */
200#define DLT_USER1 148 /* Reserved for private use */
201#define DLT_USER2 149 /* Reserved for private use */
202#define DLT_USER3 150 /* Reserved for private use */
203#define DLT_USER4 151 /* Reserved for private use */
204#define DLT_USER5 152 /* Reserved for private use */
205#define DLT_USER6 153 /* Reserved for private use */
206#define DLT_USER7 154 /* Reserved for private use */
207#define DLT_USER8 155 /* Reserved for private use */
208#define DLT_USER9 156 /* Reserved for private use */
209#define DLT_USER10 157 /* Reserved for private use */
210#define DLT_USER11 158 /* Reserved for private use */
211#define DLT_USER12 159 /* Reserved for private use */
212#define DLT_USER13 160 /* Reserved for private use */
213#define DLT_USER14 161 /* Reserved for private use */
214#define DLT_USER15 162 /* Reserved for private use */
215#define DLT_USBPCAP 249 /* USBPcap */
216#define DLT_MPLS 219 /* MPLS Provider Edge header */
217#define DLT_OPENFLOW 267 /* in-kernel OpenFlow, by pcap */
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#define BPF_MODE(code) ((code) & 0xe0)
239#define BPF_IMM 0x00
240#define BPF_ABS 0x20
241#define BPF_IND 0x40
242#define BPF_MEM 0x60
243#define BPF_LEN 0x80
244#define BPF_MSH 0xa0
245#define BPF_RND 0xc0
246
247/* alu/jmp fields */
248#define BPF_OP(code) ((code) & 0xf0)
249#define BPF_ADD 0x00
250#define BPF_SUB 0x10
251#define BPF_MUL 0x20
252#define BPF_DIV 0x30
253#define BPF_OR 0x40
254#define BPF_AND 0x50
255#define BPF_LSH 0x60
256#define BPF_RSH 0x70
257#define BPF_NEG 0x80
258#define BPF_MOD 0x90
259#define BPF_XOR 0xa0
260#define BPF_JA 0x00
261#define BPF_JEQ 0x10
262#define BPF_JGT 0x20
263#define BPF_JGE 0x30
264#define BPF_JSET 0x40
265#define BPF_SRC(code) ((code) & 0x08)
266#define BPF_K 0x00
267#define BPF_X 0x08
268
269/* ret - BPF_K and BPF_X also apply */
270#define BPF_RVAL(code) ((code) & 0x18)
271#define BPF_A 0x10
272
273/* misc */
274#define BPF_MISCOP(code) ((code) & 0xf8)
275#define BPF_TAX 0x00
276#define BPF_TXA 0x80
277
278/*
279 * The instruction data structure.
280 */
281struct bpf_insn {
282 u_int16_t code;
283 u_char jt;
284 u_char jf;
285 u_int32_t k;
286};
287
288/*
289 * Structure to retrieve available DLTs for the interface.
290 */
291struct bpf_dltlist {
292 u_int bfl_len; /* number of bfd_list array */
293 u_int *bfl_list; /* array of DLTs */
294};
295
296/*
297 * Load operations for _bpf_filter to use against the packet pointer.
298 */
299struct bpf_ops {
300 u_int32_t (*ldw)(const void *, u_int32_t, int *);
301 u_int32_t (*ldh)(const void *, u_int32_t, int *);
302 u_int32_t (*ldb)(const void *, u_int32_t, int *);
303};
304
305/*
306 * Macros for insn array initializers.
307 */
308#define BPF_STMT(code, k) { (u_int16_t)(code), 0, 0, k }
309#define BPF_JUMP(code, k, jt, jf) { (u_int16_t)(code), jt, jf, k }
310
311__BEGIN_DECLS
312u_int bpf_filter(const struct bpf_insn *, const u_char *, u_int, u_int)
313 __bounded((__buffer__, 2, 4));
314
315u_int _bpf_filter(const struct bpf_insn *, const struct bpf_ops *,
316 const void *, u_int);
317__END_DECLS
318
319#ifdef _KERNEL
320struct ifnet;
321struct mbuf;
322
323int bpf_validate(struct bpf_insn *, int);
324int bpf_mtap(caddr_t, const struct mbuf *, u_int);
325int bpf_mtap_hdr(caddr_t, const void *, u_int, const struct mbuf *, u_int);
326int bpf_mtap_af(caddr_t, u_int32_t, const struct mbuf *, u_int);
327int bpf_mtap_ether(caddr_t, const struct mbuf *, u_int);
328int bpf_tap_hdr(caddr_t, const void *, u_int, const void *, u_int, u_int);
329void bpfattach(caddr_t *, struct ifnet *, u_int, u_int);
330void bpfdetach(struct ifnet *);
331void *bpfsattach(caddr_t *, const char *, u_int, u_int);
332void *bpfxattach(caddr_t *, const char *, struct ifnet *, u_int, u_int);
333void bpfsdetach(void *);
334void bpfilterattach(int);
335
336u_int bpf_mfilter(const struct bpf_insn *, const struct mbuf *, u_int);
337#endif /* _KERNEL */
338
339/*
340 * Number of scratch memory words (for BPF_LD|BPF_MEM and BPF_ST).
341 */
342#define BPF_MEMWORDS 16
343
344#endif /* _NET_BPF_H_ */