bpf.h revision 98540
1/* 2 * Copyright (c) 1990, 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from the Stanford/CMU enet packet filter, 6 * (net/enet.c) distributed as part of 4.3BSD, and code contributed 7 * to Berkeley by Steven McCanne and Van Jacobson both of Lawrence 8 * Berkeley Laboratory. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * @(#)bpf.h 8.1 (Berkeley) 6/10/93 39 * @(#)bpf.h 1.34 (LBL) 6/16/96 40 * 41 * $FreeBSD: head/sys/net/bpf.h 98540 2002-06-21 05:29:40Z fenner $ 42 */ 43 44#ifndef _NET_BPF_H_ 45#define _NET_BPF_H_ 46 47/* BSD style release date */ 48#define BPF_RELEASE 199606 49 50typedef int32_t bpf_int32; 51typedef u_int32_t 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_WORDALIGN(x) (((x)+(BPF_ALIGNMENT-1))&~(BPF_ALIGNMENT-1)) 59 60#define BPF_MAXINSNS 512 61#define BPF_MAXBUFSIZE 0x80000 62#define BPF_MINBUFSIZE 32 63 64/* 65 * Structure for BIOCSETF. 66 */ 67struct bpf_program { 68 u_int bf_len; 69 struct bpf_insn *bf_insns; 70}; 71 72/* 73 * Struct returned by BIOCGSTATS. 74 */ 75struct bpf_stat { 76 u_int bs_recv; /* number of packets received */ 77 u_int bs_drop; /* number of packets dropped */ 78}; 79 80/* 81 * Struct return by BIOCVERSION. This represents the version number of 82 * the filter language described by the instruction encodings below. 83 * bpf understands a program iff kernel_major == filter_major && 84 * kernel_minor >= filter_minor, that is, if the value returned by the 85 * running kernel has the same major number and a minor number equal 86 * equal to or less than the filter being downloaded. Otherwise, the 87 * results are undefined, meaning an error may be returned or packets 88 * may be accepted haphazardly. 89 * It has nothing to do with the source code version. 90 */ 91struct bpf_version { 92 u_short bv_major; 93 u_short bv_minor; 94}; 95/* Current version number of filter architecture. */ 96#define BPF_MAJOR_VERSION 1 97#define BPF_MINOR_VERSION 1 98 99#define BIOCGBLEN _IOR('B',102, u_int) 100#define BIOCSBLEN _IOWR('B',102, u_int) 101#define BIOCSETF _IOW('B',103, struct bpf_program) 102#define BIOCFLUSH _IO('B',104) 103#define BIOCPROMISC _IO('B',105) 104#define BIOCGDLT _IOR('B',106, u_int) 105#define BIOCGETIF _IOR('B',107, struct ifreq) 106#define BIOCSETIF _IOW('B',108, struct ifreq) 107#define BIOCSRTIMEOUT _IOW('B',109, struct timeval) 108#define BIOCGRTIMEOUT _IOR('B',110, struct timeval) 109#define BIOCGSTATS _IOR('B',111, struct bpf_stat) 110#define BIOCIMMEDIATE _IOW('B',112, u_int) 111#define BIOCVERSION _IOR('B',113, struct bpf_version) 112#define BIOCGRSIG _IOR('B',114, u_int) 113#define BIOCSRSIG _IOW('B',115, u_int) 114#define BIOCGHDRCMPLT _IOR('B',116, u_int) 115#define BIOCSHDRCMPLT _IOW('B',117, u_int) 116#define BIOCGSEESENT _IOR('B',118, u_int) 117#define BIOCSSEESENT _IOW('B',119, u_int) 118 119/* 120 * Structure prepended to each packet. 121 */ 122struct bpf_hdr { 123 struct timeval bh_tstamp; /* time stamp */ 124 bpf_u_int32 bh_caplen; /* length of captured portion */ 125 bpf_u_int32 bh_datalen; /* original length of packet */ 126 u_short bh_hdrlen; /* length of bpf header (this struct 127 plus alignment padding) */ 128}; 129/* 130 * Because the structure above is not a multiple of 4 bytes, some compilers 131 * will insist on inserting padding; hence, sizeof(struct bpf_hdr) won't work. 132 * Only the kernel needs to know about it; applications use bh_hdrlen. 133 */ 134#ifdef _KERNEL 135#define SIZEOF_BPF_HDR (sizeof(struct bpf_hdr) <= 20 ? 18 : \ 136 sizeof(struct bpf_hdr)) 137#endif 138 139/* 140 * Data-link level type codes. 141 */ 142#define DLT_NULL 0 /* no link-layer encapsulation */ 143#define DLT_EN10MB 1 /* Ethernet (10Mb) */ 144#define DLT_EN3MB 2 /* Experimental Ethernet (3Mb) */ 145#define DLT_AX25 3 /* Amateur Radio AX.25 */ 146#define DLT_PRONET 4 /* Proteon ProNET Token Ring */ 147#define DLT_CHAOS 5 /* Chaos */ 148#define DLT_IEEE802 6 /* IEEE 802 Networks */ 149#define DLT_ARCNET 7 /* ARCNET */ 150#define DLT_SLIP 8 /* Serial Line IP */ 151#define DLT_PPP 9 /* Point-to-point Protocol */ 152#define DLT_FDDI 10 /* FDDI */ 153#define DLT_ATM_RFC1483 11 /* LLC/SNAP encapsulated atm */ 154#define DLT_RAW 12 /* raw IP */ 155 156/* 157 * These are values from BSD/OS's "bpf.h". 158 * These are not the same as the values from the traditional libpcap 159 * "bpf.h"; however, these values shouldn't be generated by any 160 * OS other than BSD/OS, so the correct values to use here are the 161 * BSD/OS values. 162 * 163 * Platforms that have already assigned these values to other 164 * DLT_ codes, however, should give these codes the values 165 * from that platform, so that programs that use these codes will 166 * continue to compile - even though they won't correctly read 167 * files of these types. 168 */ 169#define DLT_SLIP_BSDOS 15 /* BSD/OS Serial Line IP */ 170#define DLT_PPP_BSDOS 16 /* BSD/OS Point-to-point Protocol */ 171 172#define DLT_ATM_CLIP 19 /* Linux Classical-IP over ATM */ 173 174/* 175 * These values are defined by NetBSD; other platforms should refrain from 176 * using them for other purposes, so that NetBSD savefiles with link 177 * types of 50 or 51 can be read as this type on all platforms. 178 */ 179#define DLT_PPP_SERIAL 50 /* PPP over serial with HDLC encapsulation */ 180#define DLT_PPP_ETHER 51 /* PPP over Ethernet */ 181 182/* 183 * This value was defined by libpcap 0.5; platforms that have defined 184 * it with a different value should define it here with that value - 185 * a link type of 104 in a save file will be mapped to DLT_C_HDLC, 186 * whatever value that happens to be, so programs will correctly 187 * handle files with that link type regardless of the value of 188 * DLT_C_HDLC. 189 * 190 * The name DLT_C_HDLC was used by BSD/OS; we use that name for source 191 * compatibility with programs written for BSD/OS. 192 * 193 * libpcap 0.5 defined it as DLT_CHDLC; we define DLT_CHDLC as well, 194 * for source compatibility with programs written for libpcap 0.5. 195 */ 196#define DLT_C_HDLC 104 /* Cisco HDLC */ 197#define DLT_CHDLC DLT_C_HDLC 198 199#define DLT_IEEE802_11 105 /* IEEE 802.11 wireless */ 200 201/* 202 * Values between 106 and 107 are used in capture file headers as 203 * link-layer types corresponding to DLT_ types that might differ 204 * between platforms; don't use those values for new DLT_ new types. 205 */ 206 207/* 208 * OpenBSD DLT_LOOP, for loopback devices; it's like DLT_NULL, except 209 * that the AF_ type in the link-layer header is in network byte order. 210 * 211 * OpenBSD defines it as 12, but that collides with DLT_RAW, so we 212 * define it as 108 here. If OpenBSD picks up this file, it should 213 * define DLT_LOOP as 12 in its version, as per the comment above - 214 * and should not use 108 as a DLT_ value. 215 */ 216#define DLT_LOOP 108 217 218/* 219 * Values between 109 and 112 are used in capture file headers as 220 * link-layer types corresponding to DLT_ types that might differ 221 * between platforms; don't use those values for new DLT_ new types. 222 */ 223 224/* 225 * This is for Linux cooked sockets. 226 */ 227#define DLT_LINUX_SLL 113 228 229/* 230 * Apple LocalTalk hardware. 231 */ 232#define DLT_LTALK 114 233 234/* 235 * Acorn Econet. 236 */ 237#define DLT_ECONET 115 238 239/* 240 * Reserved for use with OpenBSD ipfilter. 241 */ 242#define DLT_IPFILTER 116 243 244/* 245 * Reserved for use in capture-file headers as a link-layer type 246 * corresponding to OpenBSD DLT_PFLOG; DLT_PFLOG is 17 in OpenBSD, 247 * but that's DLT_LANE8023 in SuSE 6.3, so we can't use 17 for it 248 * in capture-file headers. 249 */ 250#define DLT_PFLOG 117 251 252/* 253 * Registered for Cisco-internal use. 254 */ 255#define DLT_CISCO_IOS 118 256 257/* 258 * Reserved for 802.11 cards using the Prism II chips, with a link-layer 259 * header including Prism monitor mode information plus an 802.11 260 * header. 261 */ 262#define DLT_PRISM_HEADER 119 263 264/* 265 * Reserved for Aironet 802.11 cards, with an Aironet link-layer header 266 * (see Doug Ambrisko's FreeBSD patches). 267 */ 268#define DLT_AIRONET_HEADER 120 269 270/* 271 * The instruction encodings. 272 */ 273/* instruction classes */ 274#define BPF_CLASS(code) ((code) & 0x07) 275#define BPF_LD 0x00 276#define BPF_LDX 0x01 277#define BPF_ST 0x02 278#define BPF_STX 0x03 279#define BPF_ALU 0x04 280#define BPF_JMP 0x05 281#define BPF_RET 0x06 282#define BPF_MISC 0x07 283 284/* ld/ldx fields */ 285#define BPF_SIZE(code) ((code) & 0x18) 286#define BPF_W 0x00 287#define BPF_H 0x08 288#define BPF_B 0x10 289#define BPF_MODE(code) ((code) & 0xe0) 290#define BPF_IMM 0x00 291#define BPF_ABS 0x20 292#define BPF_IND 0x40 293#define BPF_MEM 0x60 294#define BPF_LEN 0x80 295#define BPF_MSH 0xa0 296 297/* alu/jmp fields */ 298#define BPF_OP(code) ((code) & 0xf0) 299#define BPF_ADD 0x00 300#define BPF_SUB 0x10 301#define BPF_MUL 0x20 302#define BPF_DIV 0x30 303#define BPF_OR 0x40 304#define BPF_AND 0x50 305#define BPF_LSH 0x60 306#define BPF_RSH 0x70 307#define BPF_NEG 0x80 308#define BPF_JA 0x00 309#define BPF_JEQ 0x10 310#define BPF_JGT 0x20 311#define BPF_JGE 0x30 312#define BPF_JSET 0x40 313#define BPF_SRC(code) ((code) & 0x08) 314#define BPF_K 0x00 315#define BPF_X 0x08 316 317/* ret - BPF_K and BPF_X also apply */ 318#define BPF_RVAL(code) ((code) & 0x18) 319#define BPF_A 0x10 320 321/* misc */ 322#define BPF_MISCOP(code) ((code) & 0xf8) 323#define BPF_TAX 0x00 324#define BPF_TXA 0x80 325 326/* 327 * The instruction data structure. 328 */ 329struct bpf_insn { 330 u_short code; 331 u_char jt; 332 u_char jf; 333 bpf_u_int32 k; 334}; 335 336/* 337 * Macros for insn array initializers. 338 */ 339#define BPF_STMT(code, k) { (u_short)(code), 0, 0, k } 340#define BPF_JUMP(code, k, jt, jf) { (u_short)(code), jt, jf, k } 341 342#ifdef _KERNEL 343int bpf_validate(const struct bpf_insn *, int); 344void bpf_tap(struct ifnet *, u_char *, u_int); 345void bpf_mtap(struct ifnet *, struct mbuf *); 346void bpfattach(struct ifnet *, u_int, u_int); 347void bpfdetach(struct ifnet *); 348 349void bpfilterattach(int); 350u_int bpf_filter(const struct bpf_insn *, u_char *, u_int, u_int); 351#endif 352 353/* 354 * Number of scratch memory words (for BPF_LD|BPF_MEM and BPF_ST). 355 */ 356#define BPF_MEMWORDS 16 357 358#endif 359