sys/net/bpf.h

   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. Neither the name of the University nor the names of its contributors
  19  *    may be used to endorse or promote products derived from this software
  20  *    without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  *      @(#)bpf.h       8.1 (Berkeley) 6/10/93
  35  *      @(#)bpf.h       1.34 (LBL)     6/16/96
  36  *
  37  * $FreeBSD: src/sys/net/bpf.h,v 1.21.2.4 2002/07/05 14:40:00 fenner Exp $
  38  */
  39
  40 #ifndef _NET_BPF_H_
  41 #define _NET_BPF_H_
  42
  43 #ifndef _SYS_PARAM_H_
  44 #include <sys/param.h>
  45 #endif
  46 #ifndef _SYS_TIME_H_
  47 #include <sys/time.h>
  48 #endif
  49 #ifndef _SYS_IOCCOM_H_
  50 #include <sys/ioccom.h>
  51 #endif
  52
  53 __BEGIN_DECLS
  54
  55 #define BPF_MAX_CLONES  128
  56
  57 /* BSD style release date */
  58 #define BPF_RELEASE 199606
  59
  60 typedef int32_t   bpf_int32;
  61 typedef u_int32_t bpf_u_int32;
  62
  63 /*
  64  * Alignment macros.  BPF_WORDALIGN rounds up to the next
  65  * even multiple of BPF_ALIGNMENT.
  66  */
  67 #define BPF_ALIGNMENT sizeof(long)
  68 #define BPF_WORDALIGN(x) roundup2(x, BPF_ALIGNMENT)
  69
  70 #define BPF_MAXINSNS 512
  71 #define BPF_MAXBUFSIZE 0x80000
  72 #define BPF_DEFAULTBUFSIZE 4096
  73 #define BPF_MINBUFSIZE 32
  74
  75 /*
  76  *  Structure for BIOCSETF.
  77  */
  78 struct bpf_program {
  79         u_int bf_len;
  80         struct bpf_insn *bf_insns;
  81 };
  82
  83 /*
  84  * Struct returned by BIOCGSTATS.
  85  */
  86 struct bpf_stat {
  87         u_int bs_recv;          /* number of packets received */
  88         u_int bs_drop;          /* number of packets dropped */
  89 };
  90
  91 /*
  92  * Struct return by BIOCVERSION.  This represents the version number of
  93  * the filter language described by the instruction encodings below.
  94  * bpf understands a program iff kernel_major == filter_major &&
  95  * kernel_minor >= filter_minor, that is, if the value returned by the
  96  * running kernel has the same major number and a minor number equal
  97  * equal to or less than the filter being downloaded.  Otherwise, the
  98  * results are undefined, meaning an error may be returned or packets
  99  * may be accepted haphazardly.
 100  * It has nothing to do with the source code version.
 101  */
 102 struct bpf_version {
 103         u_short bv_major;
 104         u_short bv_minor;
 105 };
 106 /* Current version number of filter architecture. */
 107 #define BPF_MAJOR_VERSION 1
 108 #define BPF_MINOR_VERSION 1
 109
 110 #define BIOCGBLEN       _IOR('B',102, u_int)
 111 #define BIOCSBLEN       _IOWR('B',102, u_int)
 112 #define BIOCSETF        _IOW('B',103, struct bpf_program)
 113 #define BIOCFLUSH       _IO('B',104)
 114 #define BIOCPROMISC     _IO('B',105)
 115 #define BIOCGDLT        _IOR('B',106, u_int)
 116 #define BIOCGETIF       _IOR('B',107, struct ifreq)
 117 #define BIOCSETIF       _IOW('B',108, struct ifreq)
 118 #define BIOCSRTIMEOUT   _IOW('B',109, struct timeval)
 119 #define BIOCGRTIMEOUT   _IOR('B',110, struct timeval)
 120 #define BIOCGSTATS      _IOR('B',111, struct bpf_stat)
 121 #define BIOCIMMEDIATE   _IOW('B',112, u_int)
 122 #define BIOCVERSION     _IOR('B',113, struct bpf_version)
 123 #define BIOCGRSIG       _IOR('B',114, u_int)
 124 #define BIOCSRSIG       _IOW('B',115, u_int)
 125 #define BIOCGHDRCMPLT   _IOR('B',116, u_int)
 126 #define BIOCSHDRCMPLT   _IOW('B',117, u_int)
 127 #define BIOCGSEESENT    _IOR('B',118, u_int)
 128 #define BIOCSSEESENT    _IOW('B',119, u_int)
 129 #define BIOCSDLT        _IOW('B',120, u_int)
 130 #define BIOCGDLTLIST    _IOWR('B',121, struct bpf_dltlist)
 131 #define BIOCLOCK        _IO('B', 122)
 132 #define BIOCSETWF       _IOW('B',123, struct bpf_program)
 133 #define BIOCGFEEDBACK    _IOR('B',124, u_int)
 134 #define BIOCSFEEDBACK    _IOW('B',125, u_int)
 135 #define BIOCFEEDBACK     BIOCSFEEDBACK          /* FreeBSD name */
 136
 137 /*
 138  * Structure prepended to each packet.
 139  */
 140 struct bpf_hdr {
 141         struct timeval  bh_tstamp;      /* time stamp */
 142         bpf_u_int32     bh_caplen;      /* length of captured portion */
 143         bpf_u_int32     bh_datalen;     /* original length of packet */
 144         u_short         bh_hdrlen;      /* length of bpf header (this struct
 145                                            plus alignment padding) */
 146 };
 147 /*
 148  * Because the structure above is not a multiple of 4 bytes, some compilers
 149  * will insist on inserting padding; hence, sizeof(struct bpf_hdr) won't work.
 150  * Only the kernel needs to know about it; applications use bh_hdrlen.
 151  */
 152 #ifdef _KERNEL
 153 #define SIZEOF_BPF_HDR  (sizeof(struct bpf_hdr) <= 20 ? 18 : \
 154     sizeof(struct bpf_hdr))
 155 #endif
 156
 157 #ifndef _NET_DLT_H
 158 #include <net/dlt.h>
 159 #endif
 160
 161 /*
 162  * The instruction encodings.
 163  */
 164 /* instruction classes */
 165 #define BPF_CLASS(code) ((code) & 0x07)
 166 #define         BPF_LD          0x00
 167 #define         BPF_LDX         0x01
 168 #define         BPF_ST          0x02
 169 #define         BPF_STX         0x03
 170 #define         BPF_ALU         0x04
 171 #define         BPF_JMP         0x05
 172 #define         BPF_RET         0x06
 173 #define         BPF_MISC        0x07
 174
 175 /* ld/ldx fields */
 176 #define BPF_SIZE(code)  ((code) & 0x18)
 177 #define         BPF_W           0x00
 178 #define         BPF_H           0x08
 179 #define         BPF_B           0x10
 180 #define BPF_MODE(code)  ((code) & 0xe0)
 181 #define         BPF_IMM         0x00
 182 #define         BPF_ABS         0x20
 183 #define         BPF_IND         0x40
 184 #define         BPF_MEM         0x60
 185 #define         BPF_LEN         0x80
 186 #define         BPF_MSH         0xa0
 187
 188 /* alu/jmp fields */
 189 #define BPF_OP(code)    ((code) & 0xf0)
 190 #define         BPF_ADD         0x00
 191 #define         BPF_SUB         0x10
 192 #define         BPF_MUL         0x20
 193 #define         BPF_DIV         0x30
 194 #define         BPF_OR          0x40
 195 #define         BPF_AND         0x50
 196 #define         BPF_LSH         0x60
 197 #define         BPF_RSH         0x70
 198 #define         BPF_NEG         0x80
 199 #define         BPF_MOD         0x90
 200 #define         BPF_XOR         0xa0
 201 #define         BPF_JA          0x00
 202 #define         BPF_JEQ         0x10
 203 #define         BPF_JGT         0x20
 204 #define         BPF_JGE         0x30
 205 #define         BPF_JSET        0x40
 206 #define BPF_SRC(code)   ((code) & 0x08)
 207 #define         BPF_K           0x00
 208 #define         BPF_X           0x08
 209
 210 /* ret - BPF_K and BPF_X also apply */
 211 #define BPF_RVAL(code)  ((code) & 0x18)
 212 #define         BPF_A           0x10
 213
 214 /* misc */
 215 #define BPF_MISCOP(code) ((code) & 0xf8)
 216 #define         BPF_TAX         0x00
 217 #define         BPF_TXA         0x80
 218
 219 /*
 220  * The instruction data structure.
 221  */
 222 struct bpf_insn {
 223         u_short         code;
 224         u_char          jt;
 225         u_char          jf;
 226         bpf_u_int32     k;
 227 };
 228
 229 /*
 230  * Macros for insn array initializers.
 231  */
 232 #define BPF_STMT(code, k) { (u_short)(code), 0, 0, k }
 233 #define BPF_JUMP(code, k, jt, jf) { (u_short)(code), jt, jf, k }
 234
 235 /*
 236  * Structure to retrieve available DLTs for the interface.
 237  */
 238 struct bpf_dltlist {
 239         u_int   bfl_len;        /* number of bfd_list array */
 240         u_int   *bfl_list;      /* array of DLTs */
 241 };
 242
 243 #ifdef _KERNEL
 244
 245 struct bpf_if;
 246 struct ifnet;
 247 struct mbuf;
 248
 249 int      bpf_validate(const struct bpf_insn *, int);
 250 void     bpf_tap(struct bpf_if *, u_char *, u_int);
 251 void     bpf_mtap(struct bpf_if *, struct mbuf *);
 252 void     bpf_mtap_family(struct bpf_if *, struct mbuf *m, __uint8_t family);
 253 void     bpf_mtap_hdr(struct bpf_if *, caddr_t, u_int, struct mbuf *, u_int);
 254 void     bpf_ptap(struct bpf_if *, struct mbuf *, const void *, u_int);
 255 void     bpfattach(struct ifnet *, u_int, u_int);
 256 void     bpfattach_dlt(struct ifnet *, u_int, u_int, struct bpf_if **);
 257 void     bpfdetach(struct ifnet *);
 258 void     bpf_gettoken(void);
 259 void     bpf_reltoken(void);
 260
 261 u_int    bpf_filter(const struct bpf_insn *, u_char *, u_int, u_int);
 262
 263 #define BPF_TAP(_ifp,_pkt,_pktlen) do {                                 \
 264         if ((_ifp)->if_bpf) {                                           \
 265                 bpf_gettoken();                                         \
 266                 if ((_ifp)->if_bpf)                                     \
 267                         bpf_tap((_ifp)->if_bpf, (_pkt), (_pktlen));     \
 268                 bpf_reltoken();                                         \
 269         }                                                               \
 270 } while (0)
 271
 272 #define BPF_MTAP(_ifp,_m) do {                                          \
 273         if ((_ifp)->if_bpf) {                                           \
 274                 bpf_gettoken();                                         \
 275                 if ((_ifp)->if_bpf)                                     \
 276                         bpf_mtap((_ifp)->if_bpf, (_m));                 \
 277                 bpf_reltoken();                                         \
 278         }                                                               \
 279 } while (0)
 280
 281 #endif  /* _KERNEL */
 282
 283 /*
 284  * Number of scratch memory words (for BPF_LD|BPF_MEM and BPF_ST).
 285  */
 286 #define BPF_MEMWORDS 16
 287
 288 __END_DECLS
 289
 290 #endif  /* !_NET_BPF_H_ */