bsd/net/bpf.h

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /*
  23  * Copyright (c) 1990, 1991, 1993
  24  *      The Regents of the University of California.  All rights reserved.
  25  *
  26  * This code is derived from the Stanford/CMU enet packet filter,
  27  * (net/enet.c) distributed as part of 4.3BSD, and code contributed
  28  * to Berkeley by Steven McCanne and Van Jacobson both of Lawrence
  29  * Berkeley Laboratory.
  30  *
  31  * Redistribution and use in source and binary forms, with or without
  32  * modification, are permitted provided that the following conditions
  33  * are met:
  34  * 1. Redistributions of source code must retain the above copyright
  35  *    notice, this list of conditions and the following disclaimer.
  36  * 2. Redistributions in binary form must reproduce the above copyright
  37  *    notice, this list of conditions and the following disclaimer in the
  38  *    documentation and/or other materials provided with the distribution.
  39  * 3. All advertising materials mentioning features or use of this software
  40  *    must display the following acknowledgement:
  41  *      This product includes software developed by the University of
  42  *      California, Berkeley and its contributors.
  43  * 4. Neither the name of the University nor the names of its contributors
  44  *    may be used to endorse or promote products derived from this software
  45  *    without specific prior written permission.
  46  *
  47  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  48  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  49  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  50  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  51  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  52  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  53  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  54  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  55  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  56  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  57  * SUCH DAMAGE.
  58  *
  59  *      @(#)bpf.h       8.1 (Berkeley) 6/10/93
  60  *      @(#)bpf.h       1.34 (LBL)     6/16/96
  61  *
  62  */
  63
  64 #ifndef _NET_BPF_H_
  65 #define _NET_BPF_H_
  66
  67 /* BSD style release date */
  68 #define BPF_RELEASE 199606
  69
  70 typedef int32_t   bpf_int32;
  71 typedef u_int32_t bpf_u_int32;
  72
  73 /*
  74  * Alignment macros.  BPF_WORDALIGN rounds up to the next
  75  * even multiple of BPF_ALIGNMENT.
  76  */
  77 #define BPF_ALIGNMENT sizeof(long)
  78 #define BPF_WORDALIGN(x) (((x)+(BPF_ALIGNMENT-1))&~(BPF_ALIGNMENT-1))
  79
  80 #define BPF_MAXINSNS 512
  81 #define BPF_MAXBUFSIZE 0x8000
  82 #define BPF_MINBUFSIZE 32
  83
  84
  85 /*
  86  *  Structure for BIOCSETF.
  87  */
  88 struct bpf_program {
  89         u_int bf_len;
  90         struct bpf_insn *bf_insns;
  91 };
  92
  93 /*
  94  * Struct returned by BIOCGSTATS.
  95  */
  96 struct bpf_stat {
  97         u_int bs_recv;          /* number of packets received */
  98         u_int bs_drop;          /* number of packets dropped */
  99 };
 100
 101 /*
 102  * Struct return by BIOCVERSION.  This represents the version number of
 103  * the filter language described by the instruction encodings below.
 104  * bpf understands a program iff kernel_major == filter_major &&
 105  * kernel_minor >= filter_minor, that is, if the value returned by the
 106  * running kernel has the same major number and a minor number equal
 107  * equal to or less than the filter being downloaded.  Otherwise, the
 108  * results are undefined, meaning an error may be returned or packets
 109  * may be accepted haphazardly.
 110  * It has nothing to do with the source code version.
 111  */
 112 struct bpf_version {
 113         u_short bv_major;
 114         u_short bv_minor;
 115 };
 116 /* Current version number of filter architecture. */
 117 #define BPF_MAJOR_VERSION 1
 118 #define BPF_MINOR_VERSION 1
 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 #define BIOCSRTIMEOUT   _IOW('B',109, struct timeval)
 129 #define BIOCGRTIMEOUT   _IOR('B',110, struct timeval)
 130 #define BIOCGSTATS      _IOR('B',111, struct bpf_stat)
 131 #define BIOCIMMEDIATE   _IOW('B',112, u_int)
 132 #define BIOCVERSION     _IOR('B',113, struct bpf_version)
 133 #define BIOCGRSIG       _IOR('B',114, u_int)
 134 #define BIOCSRSIG       _IOW('B',115, u_int)
 135
 136 /*
 137  * Structure prepended to each packet.
 138  */
 139 struct bpf_hdr {
 140         struct timeval  bh_tstamp;      /* time stamp */
 141         bpf_u_int32     bh_caplen;      /* length of captured portion */
 142         bpf_u_int32     bh_datalen;     /* original length of packet */
 143         u_short         bh_hdrlen;      /* length of bpf header (this struct
 144                                            plus alignment padding) */
 145 };
 146 /*
 147  * Because the structure above is not a multiple of 4 bytes, some compilers
 148  * will insist on inserting padding; hence, sizeof(struct bpf_hdr) won't work.
 149  * Only the kernel needs to know about it; applications use bh_hdrlen.
 150  */
 151 #ifdef KERNEL
 152 #define SIZEOF_BPF_HDR  (sizeof(struct bpf_hdr) <= 20 ? 18 : \
 153     sizeof(struct bpf_hdr))
 154 #endif
 155
 156 /*
 157  * Data-link level type codes.
 158  */
 159 #define DLT_NULL        0       /* no link-layer encapsulation */
 160 #define DLT_EN10MB      1       /* Ethernet (10Mb) */
 161 #define DLT_EN3MB       2       /* Experimental Ethernet (3Mb) */
 162 #define DLT_AX25        3       /* Amateur Radio AX.25 */
 163 #define DLT_PRONET      4       /* Proteon ProNET Token Ring */
 164 #define DLT_CHAOS       5       /* Chaos */
 165 #define DLT_IEEE802     6       /* IEEE 802 Networks */
 166 #define DLT_ARCNET      7       /* ARCNET */
 167 #define DLT_SLIP        8       /* Serial Line IP */
 168 #define DLT_PPP         9       /* Point-to-point Protocol */
 169 #define DLT_FDDI        10      /* FDDI */
 170 #define DLT_ATM_RFC1483 11      /* LLC/SNAP encapsulated atm */
 171 #define DLT_RAW         12      /* raw IP */
 172 #define DLT_SLIP_BSDOS  13      /* BSD/OS Serial Line IP */
 173 #define DLT_PPP_BSDOS   14      /* BSD/OS Point-to-point Protocol */
 174
 175 /*
 176  * The instruction encodings.
 177  */
 178 /* instruction classes */
 179 #define BPF_CLASS(code) ((code) & 0x07)
 180 #define         BPF_LD          0x00
 181 #define         BPF_LDX         0x01
 182 #define         BPF_ST          0x02
 183 #define         BPF_STX         0x03
 184 #define         BPF_ALU         0x04
 185 #define         BPF_JMP         0x05
 186 #define         BPF_RET         0x06
 187 #define         BPF_MISC        0x07
 188
 189 /* ld/ldx fields */
 190 #define BPF_SIZE(code)  ((code) & 0x18)
 191 #define         BPF_W           0x00
 192 #define         BPF_H           0x08
 193 #define         BPF_B           0x10
 194 #define BPF_MODE(code)  ((code) & 0xe0)
 195 #define         BPF_IMM         0x00
 196 #define         BPF_ABS         0x20
 197 #define         BPF_IND         0x40
 198 #define         BPF_MEM         0x60
 199 #define         BPF_LEN         0x80
 200 #define         BPF_MSH         0xa0
 201
 202 /* alu/jmp fields */
 203 #define BPF_OP(code)    ((code) & 0xf0)
 204 #define         BPF_ADD         0x00
 205 #define         BPF_SUB         0x10
 206 #define         BPF_MUL         0x20
 207 #define         BPF_DIV         0x30
 208 #define         BPF_OR          0x40
 209 #define         BPF_AND         0x50
 210 #define         BPF_LSH         0x60
 211 #define         BPF_RSH         0x70
 212 #define         BPF_NEG         0x80
 213 #define         BPF_JA          0x00
 214 #define         BPF_JEQ         0x10
 215 #define         BPF_JGT         0x20
 216 #define         BPF_JGE         0x30
 217 #define         BPF_JSET        0x40
 218 #define BPF_SRC(code)   ((code) & 0x08)
 219 #define         BPF_K           0x00
 220 #define         BPF_X           0x08
 221
 222 /* ret - BPF_K and BPF_X also apply */
 223 #define BPF_RVAL(code)  ((code) & 0x18)
 224 #define         BPF_A           0x10
 225
 226 /* misc */
 227 #define BPF_MISCOP(code) ((code) & 0xf8)
 228 #define         BPF_TAX         0x00
 229 #define         BPF_TXA         0x80
 230
 231 /*
 232  * The instruction data structure.
 233  */
 234 struct bpf_insn {
 235         u_short         code;
 236         u_char          jt;
 237         u_char          jf;
 238         bpf_u_int32     k;
 239 };
 240
 241 /*
 242  * Macros for insn array initializers.
 243  */
 244 #define BPF_STMT(code, k) { (u_short)(code), 0, 0, k }
 245 #define BPF_JUMP(code, k, jt, jf) { (u_short)(code), jt, jf, k }
 246
 247 #ifdef KERNEL
 248 int      bpf_validate __P((struct bpf_insn *, int));
 249 void     bpf_tap __P((struct ifnet *, u_char *, u_int));
 250 void     bpf_mtap __P((struct ifnet *, struct mbuf *));
 251 void     bpfattach __P(( struct ifnet *, u_int, u_int));
 252 void     bpfilterattach __P((int));
 253 u_int    bpf_filter __P((struct bpf_insn *, u_char *, u_int, u_int));
 254 #endif
 255
 256 /*
 257  * Number of scratch memory words (for BPF_LD|BPF_MEM and BPF_ST).
 258  */
 259 #define BPF_MEMWORDS 16
 260
 261 #define BPF_TAP(x, y, z) bpf_tap(x,y,z)
 262 #define BPF_MTAP(x, y) bpf_mtap(x, y)
 263 #endif