1 /* $NetBSD: bpf.h,v 1.67 2015/09/05 20:01:21 dholland Exp $ */ 2 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 8.2 (Berkeley) 1/9/95 37 * @(#) Header: bpf.h,v 1.36 97/06/12 14:29:53 leres Exp (LBL) 38 */ 39 40 #ifndef _NET_BPF_H_ 41 #define _NET_BPF_H_ 42 43 #include <sys/ioccom.h> 44 #include <sys/time.h> 45 46 /* BSD style release date */ 47 #define BPF_RELEASE 199606 48 49 /* Date when COP instructions and external memory have been released. */ 50 #define BPF_COP_EXTMEM_RELEASE 20140624 51 52 __BEGIN_DECLS 53 54 typedef int bpf_int32; 55 typedef u_int bpf_u_int32; 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_ALIGNMENT32 sizeof(int) 63 64 #define BPF_WORDALIGN(x) (((x)+(BPF_ALIGNMENT-1))&~(BPF_ALIGNMENT-1)) 65 #define BPF_WORDALIGN32(x) (((x)+(BPF_ALIGNMENT32-1))&~(BPF_ALIGNMENT32-1)) 66 67 #define BPF_MAXINSNS 512 68 #define BPF_DFLTBUFSIZE (1024*1024) /* default static upper limit */ 69 #define BPF_MAXBUFSIZE (1024*1024*16) /* hard limit on sysctl'able value */ 70 #define BPF_MINBUFSIZE 32 71 72 /* 73 * Structure for BIOCSETF. 74 */ 75 struct bpf_program { 76 u_int bf_len; 77 struct bpf_insn *bf_insns; 78 }; 79 80 /* 81 * Struct returned by BIOCGSTATS and net.bpf.stats sysctl. 82 */ 83 struct bpf_stat { 84 uint64_t bs_recv; /* number of packets received */ 85 uint64_t bs_drop; /* number of packets dropped */ 86 uint64_t bs_capt; /* number of packets captured */ 87 uint64_t bs_padding[13]; 88 }; 89 90 /* 91 * Struct returned by BIOCGSTATSOLD. 92 */ 93 struct bpf_stat_old { 94 u_int bs_recv; /* number of packets received */ 95 u_int bs_drop; /* number of packets dropped */ 96 }; 97 98 /* 99 * Struct return by BIOCVERSION. This represents the version number of 100 * the filter language described by the instruction encodings below. 101 * bpf understands a program iff kernel_major == filter_major && 102 * kernel_minor >= filter_minor, that is, if the value returned by the 103 * running kernel has the same major number and a minor number equal 104 * equal to or less than the filter being downloaded. Otherwise, the 105 * results are undefined, meaning an error may be returned or packets 106 * may be accepted haphazardly. 107 * It has nothing to do with the source code version. 108 */ 109 struct bpf_version { 110 u_short bv_major; 111 u_short bv_minor; 112 }; 113 /* Current version number of filter architecture. */ 114 #define BPF_MAJOR_VERSION 1 115 #define BPF_MINOR_VERSION 1 116 117 /* 118 * BPF ioctls 119 * 120 * The first set is for compatibility with Sun's pcc style 121 * header files. If your using gcc, we assume that you 122 * have run fixincludes so the latter set should work. 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 #ifdef COMPAT_50 133 #include <compat/sys/time.h> 134 #define BIOCSORTIMEOUT _IOW('B',109, struct timeval50) 135 #define BIOCGORTIMEOUT _IOR('B',110, struct timeval50) 136 #endif 137 #define BIOCGSTATS _IOR('B',111, struct bpf_stat) 138 #define BIOCGSTATSOLD _IOR('B',111, struct bpf_stat_old) 139 #define BIOCIMMEDIATE _IOW('B',112, u_int) 140 #define BIOCVERSION _IOR('B',113, struct bpf_version) 141 #define BIOCSTCPF _IOW('B',114, struct bpf_program) 142 #define BIOCSUDPF _IOW('B',115, struct bpf_program) 143 #define BIOCGHDRCMPLT _IOR('B',116, u_int) 144 #define BIOCSHDRCMPLT _IOW('B',117, u_int) 145 #define BIOCSDLT _IOW('B',118, u_int) 146 #define BIOCGDLTLIST _IOWR('B',119, struct bpf_dltlist) 147 #define BIOCGSEESENT _IOR('B',120, u_int) 148 #define BIOCSSEESENT _IOW('B',121, u_int) 149 #define BIOCSRTIMEOUT _IOW('B',122, struct timeval) 150 #define BIOCGRTIMEOUT _IOR('B',123, struct timeval) 151 #define BIOCGFEEDBACK _IOR('B',124, u_int) 152 #define BIOCSFEEDBACK _IOW('B',125, u_int) 153 #define BIOCFEEDBACK BIOCSFEEDBACK /* FreeBSD name */ 154 155 /* 156 * Structure prepended to each packet. This is "wire" format, so we 157 * cannot change it unfortunately to 64 bit times on 32 bit systems [yet]. 158 */ 159 struct bpf_timeval { 160 long tv_sec; 161 long tv_usec; 162 }; 163 164 struct bpf_timeval32 { 165 int32_t tv_sec; 166 int32_t tv_usec; 167 }; 168 169 struct bpf_hdr { 170 struct bpf_timeval bh_tstamp; /* time stamp */ 171 uint32_t bh_caplen; /* length of captured portion */ 172 uint32_t bh_datalen; /* original length of packet */ 173 uint16_t bh_hdrlen; /* length of bpf header (this struct 174 plus alignment padding) */ 175 }; 176 177 struct bpf_hdr32 { 178 struct bpf_timeval32 bh_tstamp; /* time stamp */ 179 uint32_t bh_caplen; /* length of captured portion */ 180 uint32_t bh_datalen; /* original length of packet */ 181 uint16_t bh_hdrlen; /* length of bpf header (this struct 182 plus alignment padding) */ 183 }; 184 /* 185 * Because the structure above is not a multiple of 4 bytes, some compilers 186 * will insist on inserting padding; hence, sizeof(struct bpf_hdr) won't work. 187 * Only the kernel needs to know about it; applications use bh_hdrlen. 188 * XXX To save a few bytes on 32-bit machines, we avoid end-of-struct 189 * XXX padding by using the size of the header data elements. This is 190 * XXX fail-safe: on new machines, we just use the 'safe' sizeof. 191 */ 192 #ifdef _KERNEL 193 #if defined(__arm32__) || defined(__i386__) || defined(__m68k__) || \ 194 defined(__mips__) || defined(__ns32k__) || defined(__vax__) || \ 195 defined(__sh__) || (defined(__sparc__) && !defined(__sparc64__)) 196 #define SIZEOF_BPF_HDR 18 197 #define SIZEOF_BPF_HDR32 18 198 #else 199 #define SIZEOF_BPF_HDR sizeof(struct bpf_hdr) 200 #define SIZEOF_BPF_HDR32 sizeof(struct bpf_hdr32) 201 #endif 202 #endif 203 204 /* Pull in data-link level type codes. */ 205 #include <net/dlt.h> 206 207 /* 208 * The instruction encodings. 209 */ 210 /* instruction classes */ 211 #define BPF_CLASS(code) ((code) & 0x07) 212 #define BPF_LD 0x00 213 #define BPF_LDX 0x01 214 #define BPF_ST 0x02 215 #define BPF_STX 0x03 216 #define BPF_ALU 0x04 217 #define BPF_JMP 0x05 218 #define BPF_RET 0x06 219 #define BPF_MISC 0x07 220 221 /* ld/ldx fields */ 222 #define BPF_SIZE(code) ((code) & 0x18) 223 #define BPF_W 0x00 224 #define BPF_H 0x08 225 #define BPF_B 0x10 226 /* 0x18 reserved; used by BSD/OS */ 227 #define BPF_MODE(code) ((code) & 0xe0) 228 #define BPF_IMM 0x00 229 #define BPF_ABS 0x20 230 #define BPF_IND 0x40 231 #define BPF_MEM 0x60 232 #define BPF_LEN 0x80 233 #define BPF_MSH 0xa0 234 /* 0xc0 reserved; used by BSD/OS */ 235 /* 0xe0 reserved; used by BSD/OS */ 236 237 /* alu/jmp fields */ 238 #define BPF_OP(code) ((code) & 0xf0) 239 #define BPF_ADD 0x00 240 #define BPF_SUB 0x10 241 #define BPF_MUL 0x20 242 #define BPF_DIV 0x30 243 #define BPF_OR 0x40 244 #define BPF_AND 0x50 245 #define BPF_LSH 0x60 246 #define BPF_RSH 0x70 247 #define BPF_NEG 0x80 248 #define BPF_MOD 0x90 249 #define BPF_XOR 0xa0 250 /* 0xb0 reserved */ 251 /* 0xc0 reserved */ 252 /* 0xd0 reserved */ 253 /* 0xe0 reserved */ 254 /* 0xf0 reserved */ 255 #define BPF_JA 0x00 256 #define BPF_JEQ 0x10 257 #define BPF_JGT 0x20 258 #define BPF_JGE 0x30 259 #define BPF_JSET 0x40 260 /* 0x50 reserved; used by BSD/OS */ 261 /* 0x60 reserved */ 262 /* 0x70 reserved */ 263 /* 0x80 reserved */ 264 /* 0x90 reserved */ 265 /* 0xa0 reserved */ 266 /* 0xb0 reserved */ 267 /* 0xc0 reserved */ 268 /* 0xd0 reserved */ 269 /* 0xe0 reserved */ 270 /* 0xf0 reserved */ 271 #define BPF_SRC(code) ((code) & 0x08) 272 #define BPF_K 0x00 273 #define BPF_X 0x08 274 275 /* ret - BPF_K and BPF_X also apply */ 276 #define BPF_RVAL(code) ((code) & 0x18) 277 #define BPF_A 0x10 278 /* 0x18 reserved */ 279 280 /* misc */ 281 #define BPF_MISCOP(code) ((code) & 0xf8) 282 #define BPF_TAX 0x00 283 /* 0x10 reserved */ 284 /* 0x18 reserved */ 285 #define BPF_COP 0x20 286 /* 0x28 reserved */ 287 /* 0x30 reserved */ 288 /* 0x38 reserved */ 289 #define BPF_COPX 0x40 /* XXX: also used by BSD/OS */ 290 /* 0x48 reserved */ 291 /* 0x50 reserved */ 292 /* 0x58 reserved */ 293 /* 0x60 reserved */ 294 /* 0x68 reserved */ 295 /* 0x70 reserved */ 296 /* 0x78 reserved */ 297 #define BPF_TXA 0x80 298 /* 0x88 reserved */ 299 /* 0x90 reserved */ 300 /* 0x98 reserved */ 301 /* 0xa0 reserved */ 302 /* 0xa8 reserved */ 303 /* 0xb0 reserved */ 304 /* 0xb8 reserved */ 305 /* 0xc0 reserved; used by BSD/OS */ 306 /* 0xc8 reserved */ 307 /* 0xd0 reserved */ 308 /* 0xd8 reserved */ 309 /* 0xe0 reserved */ 310 /* 0xe8 reserved */ 311 /* 0xf0 reserved */ 312 /* 0xf8 reserved */ 313 314 /* 315 * The instruction data structure. 316 */ 317 struct bpf_insn { 318 uint16_t code; 319 u_char jt; 320 u_char jf; 321 uint32_t k; 322 }; 323 324 /* 325 * Macros for insn array initializers. 326 */ 327 #define BPF_STMT(code, k) { (uint16_t)(code), 0, 0, k } 328 #define BPF_JUMP(code, k, jt, jf) { (uint16_t)(code), jt, jf, k } 329 330 /* 331 * Number of scratch memory words (for BPF_LD|BPF_MEM and BPF_ST). 332 */ 333 #define BPF_MEMWORDS 16 334 335 /* 336 * bpf_memword_init_t: bits indicate which words in the external memory 337 * store will be initialised by the caller before BPF program execution. 338 */ 339 typedef uint32_t bpf_memword_init_t; 340 #define BPF_MEMWORD_INIT(k) (UINT32_C(1) << (k)) 341 342 /* Note: two most significant bits are reserved by bpfjit. */ 343 __CTASSERT(BPF_MEMWORDS + 2 <= sizeof(bpf_memword_init_t) * NBBY); 344 345 #ifdef _KERNEL 346 /* 347 * Max number of external memory words (for BPF_LD|BPF_MEM and BPF_ST). 348 */ 349 #define BPF_MAX_MEMWORDS 30 350 351 __CTASSERT(BPF_MAX_MEMWORDS >= BPF_MEMWORDS); 352 __CTASSERT(BPF_MAX_MEMWORDS + 2 <= sizeof(bpf_memword_init_t) * NBBY); 353 #endif 354 355 /* 356 * Structure to retrieve available DLTs for the interface. 357 */ 358 struct bpf_dltlist { 359 u_int bfl_len; /* number of bfd_list array */ 360 u_int *bfl_list; /* array of DLTs */ 361 }; 362 363 struct bpf_ctx; 364 typedef struct bpf_ctx bpf_ctx_t; 365 366 typedef struct bpf_args { 367 const uint8_t * pkt; 368 size_t wirelen; 369 size_t buflen; 370 /* 371 * The following arguments are used only by some kernel 372 * subsystems. 373 * They aren't required for classical bpf filter programs. 374 * For such programs, bpfjit generated code doesn't read 375 * those arguments at all. Note however that bpf interpreter 376 * always needs a pointer to memstore. 377 */ 378 uint32_t * mem; /* pointer to external memory store */ 379 void * arg; /* auxiliary argument for a copfunc */ 380 } bpf_args_t; 381 382 #if defined(_KERNEL) || defined(__BPF_PRIVATE) 383 384 typedef uint32_t (*bpf_copfunc_t)(const bpf_ctx_t *, bpf_args_t *, uint32_t); 385 386 struct bpf_ctx { 387 /* 388 * BPF coprocessor functions and the number of them. 389 */ 390 const bpf_copfunc_t * copfuncs; 391 size_t nfuncs; 392 393 /* 394 * The number of memory words in the external memory store. 395 * There may be up to BPF_MAX_MEMWORDS words; if zero is set, 396 * then the internal memory store is used which has a fixed 397 * number of words (BPF_MEMWORDS). 398 */ 399 size_t extwords; 400 401 /* 402 * The bitmask indicating which words in the external memstore 403 * will be initialised by the caller. 404 */ 405 bpf_memword_init_t preinited; 406 }; 407 #endif 408 409 #ifdef _KERNEL 410 #include <net/bpfjit.h> 411 #include <net/if.h> 412 413 struct bpf_if; 414 415 struct bpf_ops { 416 void (*bpf_attach)(struct ifnet *, u_int, u_int, struct bpf_if **); 417 void (*bpf_detach)(struct ifnet *); 418 void (*bpf_change_type)(struct ifnet *, u_int, u_int); 419 420 void (*bpf_tap)(struct bpf_if *, u_char *, u_int); 421 void (*bpf_mtap)(struct bpf_if *, struct mbuf *); 422 void (*bpf_mtap2)(struct bpf_if *, void *, u_int, struct mbuf *); 423 void (*bpf_mtap_af)(struct bpf_if *, uint32_t, struct mbuf *); 424 void (*bpf_mtap_sl_in)(struct bpf_if *, u_char *, struct mbuf **); 425 void (*bpf_mtap_sl_out)(struct bpf_if *, u_char *, struct mbuf *); 426 }; 427 428 extern struct bpf_ops *bpf_ops; 429 430 static inline void 431 bpf_attach(struct ifnet *_ifp, u_int _dlt, u_int _hdrlen) 432 { 433 bpf_ops->bpf_attach(_ifp, _dlt, _hdrlen, &_ifp->if_bpf); 434 } 435 436 static inline void 437 bpf_attach2(struct ifnet *_ifp, u_int _dlt, u_int _hdrlen, struct bpf_if **_dp) 438 { 439 bpf_ops->bpf_attach(_ifp, _dlt, _hdrlen, _dp); 440 } 441 442 static inline void 443 bpf_tap(struct ifnet *_ifp, u_char *_pkt, u_int _len) 444 { 445 if (_ifp->if_bpf) 446 bpf_ops->bpf_tap(_ifp->if_bpf, _pkt, _len); 447 } 448 449 static inline void 450 bpf_mtap(struct ifnet *_ifp, struct mbuf *_m) 451 { 452 if (_ifp->if_bpf) 453 bpf_ops->bpf_mtap(_ifp->if_bpf, _m); 454 } 455 456 static inline void 457 bpf_mtap2(struct bpf_if *_bpf, void *_data, u_int _dlen, struct mbuf *_m) 458 { 459 bpf_ops->bpf_mtap2(_bpf, _data, _dlen, _m); 460 } 461 462 static inline void 463 bpf_mtap3(struct bpf_if *_bpf, struct mbuf *_m) 464 { 465 if (_bpf) 466 bpf_ops->bpf_mtap(_bpf, _m); 467 } 468 469 static inline void 470 bpf_mtap_af(struct ifnet *_ifp, uint32_t _af, struct mbuf *_m) 471 { 472 if (_ifp->if_bpf) 473 bpf_ops->bpf_mtap_af(_ifp->if_bpf, _af, _m); 474 } 475 476 static inline void 477 bpf_change_type(struct ifnet *_ifp, u_int _dlt, u_int _hdrlen) 478 { 479 bpf_ops->bpf_change_type(_ifp, _dlt, _hdrlen); 480 } 481 482 static inline void 483 bpf_detach(struct ifnet *_ifp) 484 { 485 bpf_ops->bpf_detach(_ifp); 486 } 487 488 static inline void 489 bpf_mtap_sl_in(struct ifnet *_ifp, u_char *_hdr, struct mbuf **_m) 490 { 491 bpf_ops->bpf_mtap_sl_in(_ifp->if_bpf, _hdr, _m); 492 } 493 494 static inline void 495 bpf_mtap_sl_out(struct ifnet *_ifp, u_char *_hdr, struct mbuf *_m) 496 { 497 if (_ifp->if_bpf) 498 bpf_ops->bpf_mtap_sl_out(_ifp->if_bpf, _hdr, _m); 499 } 500 501 502 void bpf_setops(void); 503 504 void bpf_ops_handover_enter(struct bpf_ops *); 505 void bpf_ops_handover_exit(void); 506 507 void bpfilterattach(int); 508 509 bpf_ctx_t *bpf_create(void); 510 void bpf_destroy(bpf_ctx_t *); 511 512 int bpf_set_cop(bpf_ctx_t *, const bpf_copfunc_t *, size_t); 513 int bpf_set_extmem(bpf_ctx_t *, size_t, bpf_memword_init_t); 514 u_int bpf_filter_ext(const bpf_ctx_t *, const struct bpf_insn *, bpf_args_t *); 515 int bpf_validate_ext(const bpf_ctx_t *, const struct bpf_insn *, int); 516 517 bpfjit_func_t bpf_jit_generate(bpf_ctx_t *, void *, size_t); 518 void bpf_jit_freecode(bpfjit_func_t); 519 520 #endif 521 522 int bpf_validate(const struct bpf_insn *, int); 523 u_int bpf_filter(const struct bpf_insn *, const u_char *, u_int, u_int); 524 525 __END_DECLS 526 527 #endif /* !_NET_BPF_H_ */ 528