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 * $FreeBSD$ 40 */ 41 42#ifndef _NET_BPF_H_ 43#define _NET_BPF_H_ 44 45#include <sys/_eventhandler.h> 46#include <sys/ck.h> 47#include <net/dlt.h> 48 49/* BSD style release date */ 50#define BPF_RELEASE 199606 51 52typedef int32_t bpf_int32; 53typedef u_int32_t bpf_u_int32; 54typedef int64_t bpf_int64; 55typedef u_int64_t bpf_u_int64; 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_WORDALIGN(x) (((x)+(BPF_ALIGNMENT-1))&~(BPF_ALIGNMENT-1)) 63 64#define BPF_MAXINSNS 512 65#define BPF_MAXBUFSIZE 0x80000 66#define BPF_MINBUFSIZE 32 67 68/* 69 * Structure for BIOCSETF. 70 */ 71struct bpf_program { 72 u_int bf_len; 73 struct bpf_insn *bf_insns; 74}; 75 76/* 77 * Struct returned by BIOCGSTATS. 78 */ 79struct bpf_stat { 80 u_int bs_recv; /* number of packets received */ 81 u_int bs_drop; /* number of packets dropped */ 82}; 83 84/* 85 * Struct return by BIOCVERSION. This represents the version number of 86 * the filter language described by the instruction encodings below. 87 * bpf understands a program iff kernel_major == filter_major && 88 * kernel_minor >= filter_minor, that is, if the value returned by the 89 * running kernel has the same major number and a minor number equal 90 * equal to or less than the filter being downloaded. Otherwise, the 91 * results are undefined, meaning an error may be returned or packets 92 * may be accepted haphazardly. 93 * It has nothing to do with the source code version. 94 */ 95struct bpf_version { 96 u_short bv_major; 97 u_short bv_minor; 98}; 99/* Current version number of filter architecture. */ 100#define BPF_MAJOR_VERSION 1 101#define BPF_MINOR_VERSION 1 102 103/* 104 * Historically, BPF has supported a single buffering model, first using mbuf 105 * clusters in kernel, and later using malloc(9) buffers in kernel. We now 106 * support multiple buffering modes, which may be queried and set using 107 * BIOCGETBUFMODE and BIOCSETBUFMODE. So as to avoid handling the complexity 108 * of changing modes while sniffing packets, the mode becomes fixed once an 109 * interface has been attached to the BPF descriptor. 110 */ 111#define BPF_BUFMODE_BUFFER 1 /* Kernel buffers with read(). */ 112#define BPF_BUFMODE_ZBUF 2 /* Zero-copy buffers. */ 113 114/*- 115 * Struct used by BIOCSETZBUF, BIOCROTZBUF: describes up to two zero-copy 116 * buffer as used by BPF. 117 */ 118struct bpf_zbuf { 119 void *bz_bufa; /* Location of 'a' zero-copy buffer. */ 120 void *bz_bufb; /* Location of 'b' zero-copy buffer. */ 121 size_t bz_buflen; /* Size of zero-copy buffers. */ 122}; 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#define BIOCSRTIMEOUT _IOW('B', 109, struct timeval) 133#define BIOCGRTIMEOUT _IOR('B', 110, struct timeval) 134#define BIOCGSTATS _IOR('B', 111, struct bpf_stat) 135#define BIOCIMMEDIATE _IOW('B', 112, u_int) 136#define BIOCVERSION _IOR('B', 113, struct bpf_version) 137#define BIOCGRSIG _IOR('B', 114, u_int) 138#define BIOCSRSIG _IOW('B', 115, u_int) 139#define BIOCGHDRCMPLT _IOR('B', 116, u_int) 140#define BIOCSHDRCMPLT _IOW('B', 117, u_int) 141#define BIOCGDIRECTION _IOR('B', 118, u_int) 142#define BIOCSDIRECTION _IOW('B', 119, u_int) 143#define BIOCSDLT _IOW('B', 120, u_int) 144#define BIOCGDLTLIST _IOWR('B', 121, struct bpf_dltlist) 145#define BIOCLOCK _IO('B', 122) 146#define BIOCSETWF _IOW('B', 123, struct bpf_program) 147#define BIOCFEEDBACK _IOW('B', 124, u_int) 148#define BIOCGETBUFMODE _IOR('B', 125, u_int) 149#define BIOCSETBUFMODE _IOW('B', 126, u_int) 150#define BIOCGETZMAX _IOR('B', 127, size_t) 151#define BIOCROTZBUF _IOR('B', 128, struct bpf_zbuf) 152#define BIOCSETZBUF _IOW('B', 129, struct bpf_zbuf) 153#define BIOCSETFNR _IOW('B', 130, struct bpf_program) 154#define BIOCGTSTAMP _IOR('B', 131, u_int) 155#define BIOCSTSTAMP _IOW('B', 132, 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_mtap(struct bpf_if *, struct mbuf *); 424void bpf_mtap2(struct bpf_if *, 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 *); 428#ifdef VIMAGE 429int bpf_get_bp_params(struct bpf_if *, u_int *, u_int *); 430#endif 431 432void bpfilterattach(int); 433u_int bpf_filter(const struct bpf_insn *, u_char *, u_int, u_int); 434 435static __inline int 436bpf_peers_present(struct bpf_if *bpf) 437{ 438 struct bpf_if_ext *ext; 439 440 ext = (struct bpf_if_ext *)bpf; 441 if (!CK_LIST_EMPTY(&ext->bif_dlist)) 442 return (1); 443 return (0); 444} 445 446#define BPF_TAP(_ifp,_pkt,_pktlen) do { \ 447 if (bpf_peers_present((_ifp)->if_bpf)) \ 448 bpf_tap((_ifp)->if_bpf, (_pkt), (_pktlen)); \ 449} while (0) 450#define BPF_MTAP(_ifp,_m) do { \ 451 if (bpf_peers_present((_ifp)->if_bpf)) { \ 452 M_ASSERTVALID(_m); \ 453 bpf_mtap((_ifp)->if_bpf, (_m)); \ 454 } \ 455} while (0) 456#define BPF_MTAP2(_ifp,_data,_dlen,_m) do { \ 457 if (bpf_peers_present((_ifp)->if_bpf)) { \ 458 M_ASSERTVALID(_m); \ 459 bpf_mtap2((_ifp)->if_bpf,(_data),(_dlen),(_m)); \ 460 } \ 461} while (0) 462#endif 463 464/* 465 * Number of scratch memory words (for BPF_LD|BPF_MEM and BPF_ST). 466 */ 467#define BPF_MEMWORDS 16 468 469/* BPF attach/detach events */ 470struct ifnet; 471typedef void (*bpf_track_fn)(void *, struct ifnet *, int /* dlt */, 472 int /* 1 =>'s attach */); 473EVENTHANDLER_DECLARE(bpf_track, bpf_track_fn); 474 475#endif /* _NET_BPF_H_ */ 476