bpf.h revision 13937
11541Srgrimes/* 21541Srgrimes * Copyright (c) 1990, 1991, 1993 31541Srgrimes * The Regents of the University of California. All rights reserved. 41541Srgrimes * 51541Srgrimes * This code is derived from the Stanford/CMU enet packet filter, 61541Srgrimes * (net/enet.c) distributed as part of 4.3BSD, and code contributed 71541Srgrimes * to Berkeley by Steven McCanne and Van Jacobson both of Lawrence 81541Srgrimes * Berkeley Laboratory. 91541Srgrimes * 101541Srgrimes * Redistribution and use in source and binary forms, with or without 111541Srgrimes * modification, are permitted provided that the following conditions 121541Srgrimes * are met: 131541Srgrimes * 1. Redistributions of source code must retain the above copyright 141541Srgrimes * notice, this list of conditions and the following disclaimer. 151541Srgrimes * 2. Redistributions in binary form must reproduce the above copyright 161541Srgrimes * notice, this list of conditions and the following disclaimer in the 171541Srgrimes * documentation and/or other materials provided with the distribution. 181541Srgrimes * 3. All advertising materials mentioning features or use of this software 191541Srgrimes * must display the following acknowledgement: 201541Srgrimes * This product includes software developed by the University of 211541Srgrimes * California, Berkeley and its contributors. 221541Srgrimes * 4. Neither the name of the University nor the names of its contributors 231541Srgrimes * may be used to endorse or promote products derived from this software 241541Srgrimes * without specific prior written permission. 251541Srgrimes * 261541Srgrimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 271541Srgrimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 281541Srgrimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 291541Srgrimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 301541Srgrimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 311541Srgrimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 321541Srgrimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 331541Srgrimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 341541Srgrimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 351541Srgrimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 361541Srgrimes * SUCH DAMAGE. 371541Srgrimes * 381541Srgrimes * @(#)bpf.h 8.1 (Berkeley) 6/10/93 391541Srgrimes * 4013937Swollman * $Id: bpf.h,v 1.8 1996/01/30 22:57:38 mpp Exp $ 411541Srgrimes */ 421541Srgrimes 432168Spaul#ifndef _NET_BPF_H_ 442168Spaul#define _NET_BPF_H_ 452168Spaul 461541Srgrimes/* 478876Srgrimes * Alignment macros. BPF_WORDALIGN rounds up to the next 488876Srgrimes * even multiple of BPF_ALIGNMENT. 491541Srgrimes */ 501541Srgrimes#define BPF_ALIGNMENT sizeof(long) 511541Srgrimes#define BPF_WORDALIGN(x) (((x)+(BPF_ALIGNMENT-1))&~(BPF_ALIGNMENT-1)) 521541Srgrimes 531541Srgrimes#define BPF_MAXINSNS 512 541541Srgrimes#define BPF_MAXBUFSIZE 0x8000 551541Srgrimes#define BPF_MINBUFSIZE 32 561541Srgrimes 571541Srgrimes/* 581541Srgrimes * Structure for BIOCSETF. 591541Srgrimes */ 601541Srgrimesstruct bpf_program { 611541Srgrimes u_int bf_len; 621541Srgrimes struct bpf_insn *bf_insns; 631541Srgrimes}; 648876Srgrimes 651541Srgrimes/* 661541Srgrimes * Struct returned by BIOCGSTATS. 671541Srgrimes */ 681541Srgrimesstruct bpf_stat { 691541Srgrimes u_int bs_recv; /* number of packets received */ 701541Srgrimes u_int bs_drop; /* number of packets dropped */ 711541Srgrimes}; 721541Srgrimes 731541Srgrimes/* 748876Srgrimes * Struct return by BIOCVERSION. This represents the version number of 751541Srgrimes * the filter language described by the instruction encodings below. 761541Srgrimes * bpf understands a program iff kernel_major == filter_major && 771541Srgrimes * kernel_minor >= filter_minor, that is, if the value returned by the 781541Srgrimes * running kernel has the same major number and a minor number equal 791541Srgrimes * equal to or less than the filter being downloaded. Otherwise, the 801541Srgrimes * results are undefined, meaning an error may be returned or packets 811541Srgrimes * may be accepted haphazardly. 821541Srgrimes * It has nothing to do with the source code version. 831541Srgrimes */ 841541Srgrimesstruct bpf_version { 851541Srgrimes u_short bv_major; 861541Srgrimes u_short bv_minor; 871541Srgrimes}; 881541Srgrimes/* Current version number. */ 891541Srgrimes#define BPF_MAJOR_VERSION 1 901541Srgrimes#define BPF_MINOR_VERSION 1 911541Srgrimes 921541Srgrimes#define BIOCGBLEN _IOR('B',102, u_int) 931541Srgrimes#define BIOCSBLEN _IOWR('B',102, u_int) 941541Srgrimes#define BIOCSETF _IOW('B',103, struct bpf_program) 951541Srgrimes#define BIOCFLUSH _IO('B',104) 961541Srgrimes#define BIOCPROMISC _IO('B',105) 971541Srgrimes#define BIOCGDLT _IOR('B',106, u_int) 981541Srgrimes#define BIOCGETIF _IOR('B',107, struct ifreq) 991541Srgrimes#define BIOCSETIF _IOW('B',108, struct ifreq) 1001541Srgrimes#define BIOCSRTIMEOUT _IOW('B',109, struct timeval) 1011541Srgrimes#define BIOCGRTIMEOUT _IOR('B',110, struct timeval) 1021541Srgrimes#define BIOCGSTATS _IOR('B',111, struct bpf_stat) 1031541Srgrimes#define BIOCIMMEDIATE _IOW('B',112, u_int) 1041541Srgrimes#define BIOCVERSION _IOR('B',113, struct bpf_version) 1059235Spst#define BIOCGRSIG _IOR('B',114, u_int) 1069235Spst#define BIOCSRSIG _IOW('B',115, u_int) 1071541Srgrimes 1081541Srgrimes/* 1091541Srgrimes * Structure prepended to each packet. 1101541Srgrimes */ 1111541Srgrimesstruct bpf_hdr { 1121541Srgrimes struct timeval bh_tstamp; /* time stamp */ 1131541Srgrimes u_long bh_caplen; /* length of captured portion */ 1141541Srgrimes u_long bh_datalen; /* original length of packet */ 1151541Srgrimes u_short bh_hdrlen; /* length of bpf header (this struct 1161541Srgrimes plus alignment padding) */ 1171541Srgrimes}; 1181541Srgrimes/* 1191541Srgrimes * Because the structure above is not a multiple of 4 bytes, some compilers 1201541Srgrimes * will insist on inserting padding; hence, sizeof(struct bpf_hdr) won't work. 1211541Srgrimes * Only the kernel needs to know about it; applications use bh_hdrlen. 1221541Srgrimes */ 1231541Srgrimes#ifdef KERNEL 1241541Srgrimes#define SIZEOF_BPF_HDR 18 1251541Srgrimes#endif 1261541Srgrimes 1271541Srgrimes/* 1281541Srgrimes * Data-link level type codes. 1291541Srgrimes * Currently, only DLT_EN10MB and DLT_SLIP are supported. 1301541Srgrimes */ 1311541Srgrimes#define DLT_NULL 0 /* no link-layer encapsulation */ 1321541Srgrimes#define DLT_EN10MB 1 /* Ethernet (10Mb) */ 1331541Srgrimes#define DLT_EN3MB 2 /* Experimental Ethernet (3Mb) */ 1341541Srgrimes#define DLT_AX25 3 /* Amateur Radio AX.25 */ 1351541Srgrimes#define DLT_PRONET 4 /* Proteon ProNET Token Ring */ 1361541Srgrimes#define DLT_CHAOS 5 /* Chaos */ 1371541Srgrimes#define DLT_IEEE802 6 /* IEEE 802 Networks */ 1381541Srgrimes#define DLT_ARCNET 7 /* ARCNET */ 1391541Srgrimes#define DLT_SLIP 8 /* Serial Line IP */ 1401541Srgrimes#define DLT_PPP 9 /* Point-to-point Protocol */ 1411541Srgrimes#define DLT_FDDI 10 /* FDDI */ 1421541Srgrimes 1431541Srgrimes/* 14413765Smpp * The instruction encodings. 1451541Srgrimes */ 1461541Srgrimes/* instruction classes */ 1471541Srgrimes#define BPF_CLASS(code) ((code) & 0x07) 1481541Srgrimes#define BPF_LD 0x00 1491541Srgrimes#define BPF_LDX 0x01 1501541Srgrimes#define BPF_ST 0x02 1511541Srgrimes#define BPF_STX 0x03 1521541Srgrimes#define BPF_ALU 0x04 1531541Srgrimes#define BPF_JMP 0x05 1541541Srgrimes#define BPF_RET 0x06 1551541Srgrimes#define BPF_MISC 0x07 1561541Srgrimes 1571541Srgrimes/* ld/ldx fields */ 1581541Srgrimes#define BPF_SIZE(code) ((code) & 0x18) 1591541Srgrimes#define BPF_W 0x00 1601541Srgrimes#define BPF_H 0x08 1611541Srgrimes#define BPF_B 0x10 1621541Srgrimes#define BPF_MODE(code) ((code) & 0xe0) 1631541Srgrimes#define BPF_IMM 0x00 1641541Srgrimes#define BPF_ABS 0x20 1651541Srgrimes#define BPF_IND 0x40 1661541Srgrimes#define BPF_MEM 0x60 1671541Srgrimes#define BPF_LEN 0x80 1681541Srgrimes#define BPF_MSH 0xa0 1691541Srgrimes 1701541Srgrimes/* alu/jmp fields */ 1711541Srgrimes#define BPF_OP(code) ((code) & 0xf0) 1721541Srgrimes#define BPF_ADD 0x00 1731541Srgrimes#define BPF_SUB 0x10 1741541Srgrimes#define BPF_MUL 0x20 1751541Srgrimes#define BPF_DIV 0x30 1761541Srgrimes#define BPF_OR 0x40 1771541Srgrimes#define BPF_AND 0x50 1781541Srgrimes#define BPF_LSH 0x60 1791541Srgrimes#define BPF_RSH 0x70 1801541Srgrimes#define BPF_NEG 0x80 1811541Srgrimes#define BPF_JA 0x00 1821541Srgrimes#define BPF_JEQ 0x10 1831541Srgrimes#define BPF_JGT 0x20 1841541Srgrimes#define BPF_JGE 0x30 1851541Srgrimes#define BPF_JSET 0x40 1861541Srgrimes#define BPF_SRC(code) ((code) & 0x08) 1871541Srgrimes#define BPF_K 0x00 1881541Srgrimes#define BPF_X 0x08 1891541Srgrimes 1901541Srgrimes/* ret - BPF_K and BPF_X also apply */ 1911541Srgrimes#define BPF_RVAL(code) ((code) & 0x18) 1921541Srgrimes#define BPF_A 0x10 1931541Srgrimes 1941541Srgrimes/* misc */ 1951541Srgrimes#define BPF_MISCOP(code) ((code) & 0xf8) 1961541Srgrimes#define BPF_TAX 0x00 1971541Srgrimes#define BPF_TXA 0x80 1981541Srgrimes 1991541Srgrimes/* 2001541Srgrimes * The instruction data structure. 2011541Srgrimes */ 2021541Srgrimesstruct bpf_insn { 2031541Srgrimes u_short code; 2041541Srgrimes u_char jt; 2051541Srgrimes u_char jf; 2061541Srgrimes long k; 2071541Srgrimes}; 2081541Srgrimes 2091541Srgrimes/* 2101541Srgrimes * Macros for insn array initializers. 2111541Srgrimes */ 2121541Srgrimes#define BPF_STMT(code, k) { (u_short)(code), 0, 0, k } 2131541Srgrimes#define BPF_JUMP(code, k, jt, jf) { (u_short)(code), jt, jf, k } 2141541Srgrimes 2151541Srgrimes#ifdef KERNEL 2161541Srgrimesint bpf_validate __P((struct bpf_insn *, int)); 21713937Swollmanvoid bpf_tap __P((struct ifnet *, u_char *, u_int)); 21813937Swollmanvoid bpf_mtap __P((struct ifnet *, struct mbuf *)); 21913937Swollmanvoid bpfattach __P((struct ifnet *, u_int, u_int)); 2201541Srgrimesvoid bpfilterattach __P((int)); 2211541Srgrimesu_int bpf_filter __P((struct bpf_insn *, u_char *, u_int, u_int)); 2221541Srgrimes#endif 2231541Srgrimes 2241541Srgrimes/* 2251541Srgrimes * Number of scratch memory words (for BPF_LD|BPF_MEM and BPF_ST). 2261541Srgrimes */ 2271541Srgrimes#define BPF_MEMWORDS 16 2281541Srgrimes 2292168Spaul#endif 230