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. 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: src/sys/net/bpf.h,v 1.21.2.4 2002/07/05 14:40:00 fenner Exp $
  42  * $DragonFly: src/sys/net/bpf.h,v 1.12 2008/03/14 09:52:10 matthias Exp $
  43  */
  44
  45 #ifndef _NET_BPF_H_
  46 #define _NET_BPF_H_
  47
  48 #ifndef _SYS_TYPES_H_
  49 #include <sys/types.h>
  50 #endif
  51 #ifndef _SYS_TIME_H_
  52 #include <sys/time.h>
  53 #endif
  54 #ifndef _SYS_IOCCOM_H_
  55 #include <sys/ioccom.h>
  56 #endif
  57
  58 __BEGIN_DECLS
  59
  60 /* BSD style release date */
  61 #define BPF_RELEASE 199606
  62
  63 typedef int32_t   bpf_int32;
  64 typedef u_int32_t bpf_u_int32;
  65
  66 /*
  67  * Alignment macros.  BPF_WORDALIGN rounds up to the next
  68  * even multiple of BPF_ALIGNMENT.
  69  */
  70 #define BPF_ALIGNMENT sizeof(long)
  71 #define BPF_WORDALIGN(x) (((x)+(BPF_ALIGNMENT-1))&~(BPF_ALIGNMENT-1))
  72
  73 #define BPF_MAXINSNS 512
  74 #define BPF_MAXBUFSIZE 0x80000
  75 #define BPF_DEFAULTBUFSIZE 4096
  76 #define BPF_MINBUFSIZE 32
  77
  78 /*
  79  *  Structure for BIOCSETF.
  80  */
  81 struct bpf_program {
  82         u_int bf_len;
  83         struct bpf_insn *bf_insns;
  84 };
  85
  86 /*
  87  * Struct returned by BIOCGSTATS.
  88  */
  89 struct bpf_stat {
  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 #define BIOCGBLEN       _IOR('B',102, u_int)
 114 #define BIOCSBLEN       _IOWR('B',102, u_int)
 115 #define BIOCSETF        _IOW('B',103, struct bpf_program)
 116 #define BIOCFLUSH       _IO('B',104)
 117 #define BIOCPROMISC     _IO('B',105)
 118 #define BIOCGDLT        _IOR('B',106, u_int)
 119 #define BIOCGETIF       _IOR('B',107, struct ifreq)
 120 #define BIOCSETIF       _IOW('B',108, struct ifreq)
 121 #define BIOCSRTIMEOUT   _IOW('B',109, struct timeval)
 122 #define BIOCGRTIMEOUT   _IOR('B',110, struct timeval)
 123 #define BIOCGSTATS      _IOR('B',111, struct bpf_stat)
 124 #define BIOCIMMEDIATE   _IOW('B',112, u_int)
 125 #define BIOCVERSION     _IOR('B',113, struct bpf_version)
 126 #define BIOCGRSIG       _IOR('B',114, u_int)
 127 #define BIOCSRSIG       _IOW('B',115, u_int)
 128 #define BIOCGHDRCMPLT   _IOR('B',116, u_int)
 129 #define BIOCSHDRCMPLT   _IOW('B',117, u_int)
 130 #define BIOCGSEESENT    _IOR('B',118, u_int)
 131 #define BIOCSSEESENT    _IOW('B',119, u_int)
 132 #define BIOCSDLT        _IOW('B',120, u_int)
 133 #define BIOCGDLTLIST    _IOWR('B',121, struct bpf_dltlist)
 134 #define BIOCLOCK        _IO('B', 122)
 135 #define BIOCSETWF       _IOW('B',123, struct bpf_program)
 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_JA          0x00
 200 #define         BPF_JEQ         0x10
 201 #define         BPF_JGT         0x20
 202 #define         BPF_JGE         0x30
 203 #define         BPF_JSET        0x40
 204 #define BPF_SRC(code)   ((code) & 0x08)
 205 #define         BPF_K           0x00
 206 #define         BPF_X           0x08
 207
 208 /* ret - BPF_K and BPF_X also apply */
 209 #define BPF_RVAL(code)  ((code) & 0x18)
 210 #define         BPF_A           0x10
 211
 212 /* misc */
 213 #define BPF_MISCOP(code) ((code) & 0xf8)
 214 #define         BPF_TAX         0x00
 215 #define         BPF_TXA         0x80
 216
 217 /*
 218  * The instruction data structure.
 219  */
 220 struct bpf_insn {
 221         u_short         code;
 222         u_char          jt;
 223         u_char          jf;
 224         bpf_u_int32     k;
 225 };
 226
 227 /*
 228  * Macros for insn array initializers.
 229  */
 230 #define BPF_STMT(code, k) { (u_short)(code), 0, 0, k }
 231 #define BPF_JUMP(code, k, jt, jf) { (u_short)(code), jt, jf, k }
 232
 233 /*
 234  * Structure to retrieve available DLTs for the interface.
 235  */
 236 struct bpf_dltlist {
 237         u_int   bfl_len;        /* number of bfd_list array */
 238         u_int   *bfl_list;      /* array of DLTs */
 239 };
 240
 241 #ifdef _KERNEL
 242 struct bpf_if;
 243 struct ifnet;
 244 struct mbuf;
 245
 246 int      bpf_validate(const struct bpf_insn *, int);
 247 void     bpf_tap(struct bpf_if *, u_char *, u_int);
 248 void     bpf_mtap(struct bpf_if *, struct mbuf *);
 249 void     bpf_mtap_family(struct bpf_if *, struct mbuf *m, __uint8_t family);
 250 void     bpf_ptap(struct bpf_if *, struct mbuf *, const void *, u_int);
 251 void     bpfattach(struct ifnet *, u_int, u_int);
 252 void     bpfattach_dlt(struct ifnet *, u_int, u_int, struct bpf_if **);
 253 void     bpfdetach(struct ifnet *);
 254
 255 void     bpfilterattach(int);
 256 u_int    bpf_filter(const struct bpf_insn *, u_char *, u_int, u_int);
 257
 258 #define BPF_TAP(_ifp,_pkt,_pktlen) do {                         \
 259         if ((_ifp)->if_bpf)                                     \
 260                 bpf_tap((_ifp)->if_bpf, (_pkt), (_pktlen));     \
 261 } while (0)
 262 #define BPF_MTAP(_ifp,_m) do {                                  \
 263         if ((_ifp)->if_bpf)                                     \
 264                 bpf_mtap((_ifp)->if_bpf, (_m));                 \
 265 } while (0)
 266 #endif
 267
 268 /*
 269  * Number of scratch memory words (for BPF_LD|BPF_MEM and BPF_ST).
 270  */
 271 #define BPF_MEMWORDS 16
 272
 273 __END_DECLS
 274
 275 #endif  /* !_NET_BPF_H_ */