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 #define BPF_MAX_CLONES  128
  61
  62 /* BSD style release date */
  63 #define BPF_RELEASE 199606
  64
  65 typedef int32_t   bpf_int32;
  66 typedef u_int32_t bpf_u_int32;
  67
  68 /*
  69  * Alignment macros.  BPF_WORDALIGN rounds up to the next
  70  * even multiple of BPF_ALIGNMENT.
  71  */
  72 #define BPF_ALIGNMENT sizeof(long)
  73 #define BPF_WORDALIGN(x) (((x)+(BPF_ALIGNMENT-1))&~(BPF_ALIGNMENT-1))
  74
  75 #define BPF_MAXINSNS 512
  76 #define BPF_MAXBUFSIZE 0x80000
  77 #define BPF_DEFAULTBUFSIZE 4096
  78 #define BPF_MINBUFSIZE 32
  79
  80 /*
  81  *  Structure for BIOCSETF.
  82  */
  83 struct bpf_program {
  84         u_int bf_len;
  85         struct bpf_insn *bf_insns;
  86 };
  87
  88 /*
  89  * Struct returned by BIOCGSTATS.
  90  */
  91 struct bpf_stat {
  92         u_int bs_recv;          /* number of packets received */
  93         u_int bs_drop;          /* number of packets dropped */
  94 };
  95
  96 /*
  97  * Struct return by BIOCVERSION.  This represents the version number of
  98  * the filter language described by the instruction encodings below.
  99  * bpf understands a program iff kernel_major == filter_major &&
 100  * kernel_minor >= filter_minor, that is, if the value returned by the
 101  * running kernel has the same major number and a minor number equal
 102  * equal to or less than the filter being downloaded.  Otherwise, the
 103  * results are undefined, meaning an error may be returned or packets
 104  * may be accepted haphazardly.
 105  * It has nothing to do with the source code version.
 106  */
 107 struct bpf_version {
 108         u_short bv_major;
 109         u_short bv_minor;
 110 };
 111 /* Current version number of filter architecture. */
 112 #define BPF_MAJOR_VERSION 1
 113 #define BPF_MINOR_VERSION 1
 114
 115 #define BIOCGBLEN       _IOR('B',102, u_int)
 116 #define BIOCSBLEN       _IOWR('B',102, u_int)
 117 #define BIOCSETF        _IOW('B',103, struct bpf_program)
 118 #define BIOCFLUSH       _IO('B',104)
 119 #define BIOCPROMISC     _IO('B',105)
 120 #define BIOCGDLT        _IOR('B',106, u_int)
 121 #define BIOCGETIF       _IOR('B',107, struct ifreq)
 122 #define BIOCSETIF       _IOW('B',108, struct ifreq)
 123 #define BIOCSRTIMEOUT   _IOW('B',109, struct timeval)
 124 #define BIOCGRTIMEOUT   _IOR('B',110, struct timeval)
 125 #define BIOCGSTATS      _IOR('B',111, struct bpf_stat)
 126 #define BIOCIMMEDIATE   _IOW('B',112, u_int)
 127 #define BIOCVERSION     _IOR('B',113, struct bpf_version)
 128 #define BIOCGRSIG       _IOR('B',114, u_int)
 129 #define BIOCSRSIG       _IOW('B',115, u_int)
 130 #define BIOCGHDRCMPLT   _IOR('B',116, u_int)
 131 #define BIOCSHDRCMPLT   _IOW('B',117, u_int)
 132 #define BIOCGSEESENT    _IOR('B',118, u_int)
 133 #define BIOCSSEESENT    _IOW('B',119, u_int)
 134 #define BIOCSDLT        _IOW('B',120, u_int)
 135 #define BIOCGDLTLIST    _IOWR('B',121, struct bpf_dltlist)
 136 #define BIOCLOCK        _IO('B', 122)
 137 #define BIOCSETWF       _IOW('B',123, struct bpf_program)
 138
 139 /*
 140  * Structure prepended to each packet.
 141  */
 142 struct bpf_hdr {
 143         struct timeval  bh_tstamp;      /* time stamp */
 144         bpf_u_int32     bh_caplen;      /* length of captured portion */
 145         bpf_u_int32     bh_datalen;     /* original length of packet */
 146         u_short         bh_hdrlen;      /* length of bpf header (this struct
 147                                            plus alignment padding) */
 148 };
 149 /*
 150  * Because the structure above is not a multiple of 4 bytes, some compilers
 151  * will insist on inserting padding; hence, sizeof(struct bpf_hdr) won't work.
 152  * Only the kernel needs to know about it; applications use bh_hdrlen.
 153  */
 154 #ifdef _KERNEL
 155 #define SIZEOF_BPF_HDR  (sizeof(struct bpf_hdr) <= 20 ? 18 : \
 156     sizeof(struct bpf_hdr))
 157 #endif
 158
 159 #ifndef _NET_DLT_H
 160 #include <net/dlt.h>
 161 #endif
 162
 163 /*
 164  * The instruction encodings.
 165  */
 166 /* instruction classes */
 167 #define BPF_CLASS(code) ((code) & 0x07)
 168 #define         BPF_LD          0x00
 169 #define         BPF_LDX         0x01
 170 #define         BPF_ST          0x02
 171 #define         BPF_STX         0x03
 172 #define         BPF_ALU         0x04
 173 #define         BPF_JMP         0x05
 174 #define         BPF_RET         0x06
 175 #define         BPF_MISC        0x07
 176
 177 /* ld/ldx fields */
 178 #define BPF_SIZE(code)  ((code) & 0x18)
 179 #define         BPF_W           0x00
 180 #define         BPF_H           0x08
 181 #define         BPF_B           0x10
 182 #define BPF_MODE(code)  ((code) & 0xe0)
 183 #define         BPF_IMM         0x00
 184 #define         BPF_ABS         0x20
 185 #define         BPF_IND         0x40
 186 #define         BPF_MEM         0x60
 187 #define         BPF_LEN         0x80
 188 #define         BPF_MSH         0xa0
 189
 190 /* alu/jmp fields */
 191 #define BPF_OP(code)    ((code) & 0xf0)
 192 #define         BPF_ADD         0x00
 193 #define         BPF_SUB         0x10
 194 #define         BPF_MUL         0x20
 195 #define         BPF_DIV         0x30
 196 #define         BPF_OR          0x40
 197 #define         BPF_AND         0x50
 198 #define         BPF_LSH         0x60
 199 #define         BPF_RSH         0x70
 200 #define         BPF_NEG         0x80
 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 struct bpf_if;
 245 struct ifnet;
 246 struct mbuf;
 247
 248 int      bpf_validate(const struct bpf_insn *, int);
 249 void     bpf_tap(struct bpf_if *, u_char *, u_int);
 250 void     bpf_mtap(struct bpf_if *, struct mbuf *);
 251 void     bpf_mtap_family(struct bpf_if *, struct mbuf *m, __uint8_t family);
 252 void     bpf_ptap(struct bpf_if *, struct mbuf *, const void *, u_int);
 253 void     bpfattach(struct ifnet *, u_int, u_int);
 254 void     bpfattach_dlt(struct ifnet *, u_int, u_int, struct bpf_if **);
 255 void     bpfdetach(struct ifnet *);
 256
 257 void     bpfilterattach(int);
 258 u_int    bpf_filter(const struct bpf_insn *, u_char *, u_int, u_int);
 259
 260 #define BPF_TAP(_ifp,_pkt,_pktlen) do {                         \
 261         if ((_ifp)->if_bpf)                                     \
 262                 bpf_tap((_ifp)->if_bpf, (_pkt), (_pktlen));     \
 263 } while (0)
 264 #define BPF_MTAP(_ifp,_m) do {                                  \
 265         if ((_ifp)->if_bpf)                                     \
 266                 bpf_mtap((_ifp)->if_bpf, (_m));                 \
 267 } while (0)
 268 #endif
 269
 270 /*
 271  * Number of scratch memory words (for BPF_LD|BPF_MEM and BPF_ST).
 272  */
 273 #define BPF_MEMWORDS 16
 274
 275 __END_DECLS
 276
 277 #endif  /* !_NET_BPF_H_ */