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
50 typedef int32_t bpf_int32;
51 typedef u_int32_t bpf_u_int32;
52 typedef int64_t bpf_int64;
53 typedef u_int64_t bpf_u_int64;
54 struct 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 */
70 struct bpf_program {
71 u_int bf_len;
72 struct bpf_insn *bf_insns;
73 };
74
75 /*
76 * Struct returned by BIOCGSTATS.
77 */
78 struct 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 */
94 struct 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 */
117 struct 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 */
162 enum 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 */
198 struct bpf_ts {
199 bpf_int64 bt_sec; /* seconds */
200 bpf_u_int64 bt_frac; /* fraction */
201 };
202 struct 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 */
210 struct 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 */
233 struct 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 [email protected] 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 */
363 struct 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 */
379 struct 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
386 MALLOC_DECLARE(M_BPF);
387 #endif
388 #ifdef SYSCTL_DECL
389 SYSCTL_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 */
412 struct bpf_if;
413 CK_LIST_HEAD(bpfd_list, bpf_d);
414
415 struct 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
420 void bpf_bufheld(struct bpf_d *d);
421 int bpf_validate(const struct bpf_insn *, int);
422 void bpf_tap(struct bpf_if *, u_char *, u_int);
423 void bpf_tap_if(struct ifnet *, u_char *, u_int);
424 void bpf_mtap(struct bpf_if *, struct mbuf *);
425 void bpf_mtap_if(struct ifnet *, struct mbuf *);
426 void bpf_mtap2(struct bpf_if *, void *, u_int, struct mbuf *);
427 void bpf_mtap2_if(struct ifnet *, void *, u_int, struct mbuf *);
428 void bpfattach(struct ifnet *, u_int, u_int);
429 void bpfattach2(struct ifnet *, u_int, u_int, struct bpf_if **);
430 void bpfdetach(struct ifnet *);
431 bool bpf_peers_present_if(struct ifnet *);
432 #ifdef VIMAGE
433 int bpf_get_bp_params(struct bpf_if *, u_int *, u_int *);
434 #endif
435
436 void bpfilterattach(int);
437 u_int bpf_filter(const struct bpf_insn *, u_char *, u_int, u_int);
438
439 static __inline bool
bpf_peers_present(struct bpf_if * bpf)440 bpf_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 */
462 typedef void (*bpf_track_fn)(void *, struct ifnet *, int /* dlt */,
463 int /* 1 =>'s attach */);
464 EVENTHANDLER_DECLARE(bpf_track, bpf_track_fn);
465
466 #endif /* _NET_BPF_H_ */
467