1 /* $NetBSD: bpf.h,v 1.63 2013/11/15 00:12:44 rmind 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/time.h> 44 45 /* BSD style release date */ 46 #define BPF_RELEASE 199606 47 48 __BEGIN_DECLS 49 50 typedef int bpf_int32; 51 typedef u_int bpf_u_int32; 52 53 /* 54 * Alignment macros. BPF_WORDALIGN rounds up to the next 55 * even multiple of BPF_ALIGNMENT. 56 */ 57 #define BPF_ALIGNMENT sizeof(long) 58 #define BPF_ALIGNMENT32 sizeof(int) 59 60 #define BPF_WORDALIGN(x) (((x)+(BPF_ALIGNMENT-1))&~(BPF_ALIGNMENT-1)) 61 #define BPF_WORDALIGN32(x) (((x)+(BPF_ALIGNMENT32-1))&~(BPF_ALIGNMENT32-1)) 62 63 #define BPF_MAXINSNS 512 64 #define BPF_DFLTBUFSIZE (1024*1024) /* default static upper limit */ 65 #define BPF_MAXBUFSIZE (1024*1024*16) /* hard limit on sysctl'able value */ 66 #define BPF_MINBUFSIZE 32 67 68 /* 69 * Structure for BIOCSETF. 70 */ 71 struct bpf_program { 72 u_int bf_len; 73 struct bpf_insn *bf_insns; 74 }; 75 76 /* 77 * Struct returned by BIOCGSTATS and net.bpf.stats sysctl. 78 */ 79 struct bpf_stat { 80 uint64_t bs_recv; /* number of packets received */ 81 uint64_t bs_drop; /* number of packets dropped */ 82 uint64_t bs_capt; /* number of packets captured */ 83 uint64_t bs_padding[13]; 84 }; 85 86 /* 87 * Struct returned by BIOCGSTATSOLD. 88 */ 89 struct bpf_stat_old { 90 u_int bs_recv; /* number of packets received */ 91 u_int bs_drop; /* number of packets dropped */ 92 }; 93 94 /* 95 * Struct return by BIOCVERSION. This represents the version number of 96 * the filter language described by the instruction encodings below. 97 * bpf understands a program iff kernel_major == filter_major && 98 * kernel_minor >= filter_minor, that is, if the value returned by the 99 * running kernel has the same major number and a minor number equal 100 * equal to or less than the filter being downloaded. Otherwise, the 101 * results are undefined, meaning an error may be returned or packets 102 * may be accepted haphazardly. 103 * It has nothing to do with the source code version. 104 */ 105 struct bpf_version { 106 u_short bv_major; 107 u_short bv_minor; 108 }; 109 /* Current version number of filter architecture. */ 110 #define BPF_MAJOR_VERSION 1 111 #define BPF_MINOR_VERSION 1 112 113 /* 114 * BPF ioctls 115 * 116 * The first set is for compatibility with Sun's pcc style 117 * header files. If your using gcc, we assume that you 118 * have run fixincludes so the latter set should work. 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 #ifdef COMPAT_50 129 #include <compat/sys/time.h> 130 #define BIOCSORTIMEOUT _IOW('B',109, struct timeval50) 131 #define BIOCGORTIMEOUT _IOR('B',110, struct timeval50) 132 #endif 133 #define BIOCGSTATS _IOR('B',111, struct bpf_stat) 134 #define BIOCGSTATSOLD _IOR('B',111, struct bpf_stat_old) 135 #define BIOCIMMEDIATE _IOW('B',112, u_int) 136 #define BIOCVERSION _IOR('B',113, struct bpf_version) 137 #define BIOCSTCPF _IOW('B',114, struct bpf_program) 138 #define BIOCSUDPF _IOW('B',115, struct bpf_program) 139 #define BIOCGHDRCMPLT _IOR('B',116, u_int) 140 #define BIOCSHDRCMPLT _IOW('B',117, u_int) 141 #define BIOCSDLT _IOW('B',118, u_int) 142 #define BIOCGDLTLIST _IOWR('B',119, struct bpf_dltlist) 143 #define BIOCGSEESENT _IOR('B',120, u_int) 144 #define BIOCSSEESENT _IOW('B',121, u_int) 145 #define BIOCSRTIMEOUT _IOW('B',122, struct timeval) 146 #define BIOCGRTIMEOUT _IOR('B',123, struct timeval) 147 #define BIOCGFEEDBACK _IOR('B',124, u_int) 148 #define BIOCSFEEDBACK _IOW('B',125, u_int) 149 #define BIOCFEEDBACK BIOCSFEEDBACK /* FreeBSD name */ 150 151 /* 152 * Structure prepended to each packet. This is "wire" format, so we 153 * cannot change it unfortunately to 64 bit times on 32 bit systems [yet]. 154 */ 155 struct bpf_timeval { 156 long tv_sec; 157 long tv_usec; 158 }; 159 160 struct bpf_timeval32 { 161 int32_t tv_sec; 162 int32_t tv_usec; 163 }; 164 165 struct bpf_hdr { 166 struct bpf_timeval bh_tstamp; /* time stamp */ 167 uint32_t bh_caplen; /* length of captured portion */ 168 uint32_t bh_datalen; /* original length of packet */ 169 uint16_t bh_hdrlen; /* length of bpf header (this struct 170 plus alignment padding) */ 171 }; 172 173 struct bpf_hdr32 { 174 struct bpf_timeval32 bh_tstamp; /* time stamp */ 175 uint32_t bh_caplen; /* length of captured portion */ 176 uint32_t bh_datalen; /* original length of packet */ 177 uint16_t bh_hdrlen; /* length of bpf header (this struct 178 plus alignment padding) */ 179 }; 180 /* 181 * Because the structure above is not a multiple of 4 bytes, some compilers 182 * will insist on inserting padding; hence, sizeof(struct bpf_hdr) won't work. 183 * Only the kernel needs to know about it; applications use bh_hdrlen. 184 * XXX To save a few bytes on 32-bit machines, we avoid end-of-struct 185 * XXX padding by using the size of the header data elements. This is 186 * XXX fail-safe: on new machines, we just use the 'safe' sizeof. 187 */ 188 #ifdef _KERNEL 189 #if defined(__arm32__) || defined(__i386__) || defined(__m68k__) || \ 190 defined(__mips__) || defined(__ns32k__) || defined(__vax__) || \ 191 defined(__sh__) || (defined(__sparc__) && !defined(__sparc64__)) 192 #define SIZEOF_BPF_HDR 18 193 #define SIZEOF_BPF_HDR32 18 194 #else 195 #define SIZEOF_BPF_HDR sizeof(struct bpf_hdr) 196 #define SIZEOF_BPF_HDR32 sizeof(struct bpf_hdr32) 197 #endif 198 #endif 199 200 /* Pull in data-link level type codes. */ 201 #include <net/dlt.h> 202 203 /* 204 * The instruction encodings. 205 */ 206 /* instruction classes */ 207 #define BPF_CLASS(code) ((code) & 0x07) 208 #define BPF_LD 0x00 209 #define BPF_LDX 0x01 210 #define BPF_ST 0x02 211 #define BPF_STX 0x03 212 #define BPF_ALU 0x04 213 #define BPF_JMP 0x05 214 #define BPF_RET 0x06 215 #define BPF_MISC 0x07 216 217 /* ld/ldx fields */ 218 #define BPF_SIZE(code) ((code) & 0x18) 219 #define BPF_W 0x00 220 #define BPF_H 0x08 221 #define BPF_B 0x10 222 #define BPF_MODE(code) ((code) & 0xe0) 223 #define BPF_IMM 0x00 224 #define BPF_ABS 0x20 225 #define BPF_IND 0x40 226 #define BPF_MEM 0x60 227 #define BPF_LEN 0x80 228 #define BPF_MSH 0xa0 229 230 /* alu/jmp fields */ 231 #define BPF_OP(code) ((code) & 0xf0) 232 #define BPF_ADD 0x00 233 #define BPF_SUB 0x10 234 #define BPF_MUL 0x20 235 #define BPF_DIV 0x30 236 #define BPF_OR 0x40 237 #define BPF_AND 0x50 238 #define BPF_LSH 0x60 239 #define BPF_RSH 0x70 240 #define BPF_NEG 0x80 241 #define BPF_JA 0x00 242 #define BPF_JEQ 0x10 243 #define BPF_JGT 0x20 244 #define BPF_JGE 0x30 245 #define BPF_JSET 0x40 246 #define BPF_SRC(code) ((code) & 0x08) 247 #define BPF_K 0x00 248 #define BPF_X 0x08 249 250 /* ret - BPF_K and BPF_X also apply */ 251 #define BPF_RVAL(code) ((code) & 0x18) 252 #define BPF_A 0x10 253 254 /* misc */ 255 #define BPF_MISCOP(code) ((code) & 0xf8) 256 #define BPF_TAX 0x00 257 #define BPF_COP 0x20 258 #define BPF_COPX 0x40 259 #define BPF_TXA 0x80 260 261 /* 262 * The instruction data structure. 263 */ 264 struct bpf_insn { 265 uint16_t code; 266 u_char jt; 267 u_char jf; 268 uint32_t k; 269 }; 270 271 /* 272 * Macros for insn array initializers. 273 */ 274 #define BPF_STMT(code, k) { (uint16_t)(code), 0, 0, k } 275 #define BPF_JUMP(code, k, jt, jf) { (uint16_t)(code), jt, jf, k } 276 277 /* 278 * Number of scratch memory words (for BPF_LD|BPF_MEM and BPF_ST). 279 */ 280 #define BPF_MEMWORDS 16 281 282 /* 283 * Structure to retrieve available DLTs for the interface. 284 */ 285 struct bpf_dltlist { 286 u_int bfl_len; /* number of bfd_list array */ 287 u_int *bfl_list; /* array of DLTs */ 288 }; 289 290 struct bpf_ctx; 291 typedef struct bpf_ctx bpf_ctx_t; 292 293 struct bpf_args; 294 typedef struct bpf_args bpf_args_t; 295 296 #if defined(_KERNEL) || defined(__BPF_PRIVATE) 297 typedef uint32_t (*bpf_copfunc_t)(bpf_ctx_t *, bpf_args_t *, uint32_t); 298 299 struct bpf_args { 300 const struct mbuf * pkt; 301 size_t wirelen; 302 size_t buflen; 303 uint32_t mem[BPF_MEMWORDS]; 304 void * arg; 305 }; 306 307 struct bpf_ctx { 308 const bpf_copfunc_t * copfuncs; 309 size_t nfuncs; 310 }; 311 #endif 312 313 #ifdef _KERNEL 314 #include <net/bpfjit.h> 315 #include <net/if.h> 316 317 struct bpf_if; 318 319 struct bpf_ops { 320 void (*bpf_attach)(struct ifnet *, u_int, u_int, struct bpf_if **); 321 void (*bpf_detach)(struct ifnet *); 322 void (*bpf_change_type)(struct ifnet *, u_int, u_int); 323 324 void (*bpf_tap)(struct bpf_if *, u_char *, u_int); 325 void (*bpf_mtap)(struct bpf_if *, struct mbuf *); 326 void (*bpf_mtap2)(struct bpf_if *, void *, u_int, struct mbuf *); 327 void (*bpf_mtap_af)(struct bpf_if *, uint32_t, struct mbuf *); 328 void (*bpf_mtap_sl_in)(struct bpf_if *, u_char *, struct mbuf **); 329 void (*bpf_mtap_sl_out)(struct bpf_if *, u_char *, struct mbuf *); 330 }; 331 332 extern struct bpf_ops *bpf_ops; 333 334 static inline void 335 bpf_attach(struct ifnet *_ifp, u_int _dlt, u_int _hdrlen) 336 { 337 bpf_ops->bpf_attach(_ifp, _dlt, _hdrlen, &_ifp->if_bpf); 338 } 339 340 static inline void 341 bpf_attach2(struct ifnet *_ifp, u_int _dlt, u_int _hdrlen, struct bpf_if **_dp) 342 { 343 bpf_ops->bpf_attach(_ifp, _dlt, _hdrlen, _dp); 344 } 345 346 static inline void 347 bpf_tap(struct ifnet *_ifp, u_char *_pkt, u_int _len) 348 { 349 if (_ifp->if_bpf) 350 bpf_ops->bpf_tap(_ifp->if_bpf, _pkt, _len); 351 } 352 353 static inline void 354 bpf_mtap(struct ifnet *_ifp, struct mbuf *_m) 355 { 356 if (_ifp->if_bpf) 357 bpf_ops->bpf_mtap(_ifp->if_bpf, _m); 358 } 359 360 static inline void 361 bpf_mtap2(struct bpf_if *_bpf, void *_data, u_int _dlen, struct mbuf *_m) 362 { 363 bpf_ops->bpf_mtap2(_bpf, _data, _dlen, _m); 364 } 365 366 static inline void 367 bpf_mtap3(struct bpf_if *_bpf, struct mbuf *_m) 368 { 369 if (_bpf) 370 bpf_ops->bpf_mtap(_bpf, _m); 371 } 372 373 static inline void 374 bpf_mtap_af(struct ifnet *_ifp, uint32_t _af, struct mbuf *_m) 375 { 376 if (_ifp->if_bpf) 377 bpf_ops->bpf_mtap_af(_ifp->if_bpf, _af, _m); 378 } 379 380 static inline void 381 bpf_change_type(struct ifnet *_ifp, u_int _dlt, u_int _hdrlen) 382 { 383 bpf_ops->bpf_change_type(_ifp, _dlt, _hdrlen); 384 } 385 386 static inline void 387 bpf_detach(struct ifnet *_ifp) 388 { 389 bpf_ops->bpf_detach(_ifp); 390 } 391 392 static inline void 393 bpf_mtap_sl_in(struct ifnet *_ifp, u_char *_hdr, struct mbuf **_m) 394 { 395 bpf_ops->bpf_mtap_sl_in(_ifp->if_bpf, _hdr, _m); 396 } 397 398 static inline void 399 bpf_mtap_sl_out(struct ifnet *_ifp, u_char *_hdr, struct mbuf *_m) 400 { 401 if (_ifp->if_bpf) 402 bpf_ops->bpf_mtap_sl_out(_ifp->if_bpf, _hdr, _m); 403 } 404 405 406 void bpf_setops(void); 407 408 void bpf_ops_handover_enter(struct bpf_ops *); 409 void bpf_ops_handover_exit(void); 410 411 void bpfilterattach(int); 412 413 bpf_ctx_t *bpf_create(void); 414 bpf_ctx_t *bpf_default_ctx(void); 415 void bpf_destroy(bpf_ctx_t *); 416 417 int bpf_set_cop(bpf_ctx_t *, const bpf_copfunc_t *, size_t); 418 u_int bpf_filter_ext(bpf_ctx_t *, const struct bpf_insn *, bpf_args_t *); 419 int bpf_validate_ext(bpf_ctx_t *, const struct bpf_insn *, int); 420 421 bpfjit_func_t bpf_jit_generate(bpf_ctx_t *, void *, size_t); 422 void bpf_jit_freecode(bpfjit_func_t); 423 424 #endif 425 426 int bpf_validate(const struct bpf_insn *, int); 427 u_int bpf_filter(const struct bpf_insn *, const u_char *, u_int, u_int); 428 429 __END_DECLS 430 431 #endif /* !_NET_BPF_H_ */ 432