/*!\file net/bpf.h
 * Berkeley Packet Filter.
 */
/*
 * Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from the Stanford/CMU enet packet filter,
 * (net/enet.c) distributed as part of 4.3BSD, and code contributed
 * to Berkeley by Steven McCanne and Van Jacobson both of Lawrence
 * Berkeley Laboratory.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *  This product includes software developed by the University of
 *  California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *  @(#)bpf.h   8.1 (Berkeley) 6/10/93
 * @(#) Header: bpf.h,v 1.36 97/06/12 14:29:53 leres Exp  (LBL)
 */

#ifndef __NET_BPF_H
#define __NET_BPF_H

#ifndef __SYS_WTYPES_H
#include <sys/wtypes.h>
#endif

#ifndef __SYS_WTIME_H
#include <sys/wtime.h>
#endif

/* BSD style release date */
#define BPF_RELEASE 199606

typedef long      bpf_int32;
typedef u_int32_t bpf_u_int32;

/*
 * Alignment macros.  BPF_WORDALIGN rounds up to the next
 * even multiple of BPF_ALIGNMENT.
 */
#define BPF_ALIGNMENT    sizeof(long)
#define BPF_WORDALIGN(x) (((x)+(BPF_ALIGNMENT-1)) & ~(BPF_ALIGNMENT-1))

#define BPF_MAXINSNS     512
#define BPF_MAXBUFSIZE   0x8000
#define BPF_MINBUFSIZE   32

/*
 *  Structure for BIOCSETF.
 */
struct bpf_program {
       u_int            bf_len;
       struct bpf_insn *bf_insns;
     };

/*
 * Struct returned by BIOCGSTATS.
 */
struct bpf_stat {
       u_int bs_recv;          /* number of packets received */
       u_int bs_drop;          /* number of packets dropped */
     };

/*
 * Struct return by BIOCVERSION.  This represents the version number of
 * the filter language described by the instruction encodings below.
 * bpf understands a program iff kernel_major == filter_major &&
 * kernel_minor >= filter_minor, that is, if the value returned by the
 * running kernel has the same major number and a minor number equal
 * equal to or less than the filter being downloaded.  Otherwise, the
 * results are undefined, meaning an error may be returned or packets
 * may be accepted haphazardly.
 * It has nothing to do with the source code version.
 */
struct bpf_version {
       u_short bv_major;
       u_short bv_minor;
     };

/* Current version number of filter architecture. */
#define BPF_MAJOR_VERSION 1
#define BPF_MINOR_VERSION 1

/*
 * BPF ioctls
 *
 * The first set is for compatibility with Sun's pcc style
 * header files.  If your using gcc, we assume that you
 * have run fixincludes so the latter set should work.
 */
#if (defined(sun) || defined(ibm032)) && !defined(__GNUC__)
#  define BIOCGBLEN       _IOR(B,102, u_int)
#  define BIOCSBLEN       _IOWR(B,102, u_int)
#  define BIOCSETF        _IOW(B,103, struct bpf_program)
#  define BIOCFLUSH       _IO(B,104)
#  define BIOCPROMISC     _IO(B,105)
#  define BIOCGDLT        _IOR(B,106, u_int)
#  define BIOCGETIF       _IOR(B,107, struct ifreq)
#  define BIOCSETIF       _IOW(B,108, struct ifreq)
#  define BIOCSRTIMEOUT   _IOW(B,109, struct timeval)
#  define BIOCGRTIMEOUT   _IOR(B,110, struct timeval)
#  define BIOCGSTATS      _IOR(B,111, struct bpf_stat)
#  define BIOCIMMEDIATE   _IOW(B,112, u_int)
#  define BIOCVERSION     _IOR(B,113, struct bpf_version)
#  define BIOCSTCPF       _IOW(B,114, struct bpf_program)
#  define BIOCSUDPF       _IOW(B,115, struct bpf_program)
#else
#  define BIOCGBLEN       _IOR('B',102, u_int)
#  define BIOCSBLEN       _IOWR('B',102, u_int)
#  define BIOCSETF        _IOW('B',103, struct bpf_program)
#  define BIOCFLUSH       _IO('B',104)
#  define BIOCPROMISC     _IO('B',105)
#  define BIOCGDLT        _IOR('B',106, u_int)
#  define BIOCGETIF       _IOR('B',107, struct ifreq)
#  define BIOCSETIF       _IOW('B',108, struct ifreq)
#  define BIOCSRTIMEOUT   _IOW('B',109, struct timeval)
#  define BIOCGRTIMEOUT   _IOR('B',110, struct timeval)
#  define BIOCGSTATS      _IOR('B',111, struct bpf_stat)
#  define BIOCIMMEDIATE   _IOW('B',112, u_int)
#  define BIOCVERSION     _IOR('B',113, struct bpf_version)
#  define BIOCSTCPF       _IOW('B',114, struct bpf_program)
#  define BIOCSUDPF       _IOW('B',115, struct bpf_program)
#endif

/*
 * Structure prepended to each packet.
 */
struct bpf_hdr {
       struct timeval bh_tstamp;      /* time stamp */
       u_int32_t      bh_caplen;      /* length of captured portion */
       u_int32_t      bh_datalen;     /* original length of packet */
       u_int16_t      bh_hdrlen;      /* length of bpf header (this struct */
     };                               /* plus alignment padding) */

/*
 * Because the structure above is not a multiple of 4 bytes, some compilers
 * will insist on inserting padding; hence, sizeof(struct bpf_hdr) won't work.
 * Only the kernel needs to know about it; applications use bh_hdrlen.
 * XXX To save a few bytes on 32-bit machines, we avoid end-of-struct
 * XXX padding by using the size of the header data elements.  This is
 * XXX fail-safe: on new machines, we just use the 'safe' sizeof.
 */
#define SIZEOF_BPF_HDR sizeof(struct bpf_hdr)

/*
 * Data-link level type codes.
 */
#define DLT_NULL        0   /* no link-layer encapsulation */
#define DLT_EN10MB      1   /* Ethernet (10Mb) */
#define DLT_EN3MB       2   /* Experimental Ethernet (3Mb) */
#define DLT_AX25        3   /* Amateur Radio AX.25 */
#define DLT_PRONET      4   /* Proteon ProNET Token Ring */
#define DLT_CHAOS       5   /* Chaos */
#define DLT_IEEE802     6   /* IEEE 802 Networks */
#define DLT_ARCNET      7   /* ARCNET */
#define DLT_SLIP        8   /* Serial Line IP */
#define DLT_PPP         9   /* Point-to-point Protocol */
#define DLT_FDDI        10  /* FDDI */
#define DLT_ATM_RFC1483 11  /* LLC/SNAP encapsulated atm */
#define DLT_RAW         12  /* raw IP */
#define DLT_SLIP_BSDOS  13  /* BSD/OS Serial Line IP */
#define DLT_PPP_BSDOS   14  /* BSD/OS Point-to-point Protocol */
#define DLT_LANE8023    15  /* LANE 802.3(Ethernet) */
#define DLT_CIP         16  /* ATM Classical IP */

/*
 * The instruction encondings.
 */
/* instruction classes */
#define BPF_CLASS(code) ((code) & 0x07)
#define     BPF_LD      0x00
#define     BPF_LDX     0x01
#define     BPF_ST      0x02
#define     BPF_STX     0x03
#define     BPF_ALU     0x04
#define     BPF_JMP     0x05
#define     BPF_RET     0x06
#define     BPF_MISC    0x07

/* ld/ldx fields */
#define BPF_SIZE(code)  ((code) & 0x18)
#define     BPF_W       0x00
#define     BPF_H       0x08
#define     BPF_B       0x10
#define BPF_MODE(code)  ((code) & 0xe0)
#define     BPF_IMM     0x00
#define     BPF_ABS     0x20
#define     BPF_IND     0x40
#define     BPF_MEM     0x60
#define     BPF_LEN     0x80
#define     BPF_MSH     0xa0

/* alu/jmp fields */
#define BPF_OP(code)    ((code) & 0xf0)
#define     BPF_ADD     0x00
#define     BPF_SUB     0x10
#define     BPF_MUL     0x20
#define     BPF_DIV     0x30
#define     BPF_OR      0x40
#define     BPF_AND     0x50
#define     BPF_LSH     0x60
#define     BPF_RSH     0x70
#define     BPF_NEG     0x80
#define     BPF_JA      0x00
#define     BPF_JEQ     0x10
#define     BPF_JGT     0x20
#define     BPF_JGE     0x30
#define     BPF_JSET    0x40
#define BPF_SRC(code)   ((code) & 0x08)
#define     BPF_K       0x00
#define     BPF_X       0x08

/* ret - BPF_K and BPF_X also apply */
#define BPF_RVAL(code)  ((code) & 0x18)
#define     BPF_A       0x10

/* misc */
#define BPF_MISCOP(code) ((code) & 0xf8)
#define     BPF_TAX     0x00
#define     BPF_TXA     0x80

/*
 * The instruction data structure.
 */
struct bpf_insn {
       u_int16_t code;
       u_char    jt;
       u_char    jf;
       int32_t   k;
     };

/*
 * Macros for insn array initializers.
 */
#define BPF_STMT(code, k)          { (u_int16_t)(code), 0, 0, k }
#define BPF_JUMP(code, k, jt, jf)  { (u_int16_t)(code), jt, jf, k }

u_int bpf_filter (struct bpf_insn *, u_char *, u_int, u_int);

/*
 * Number of scratch memory words (for BPF_LD|BPF_MEM and BPF_ST).
 */
#define BPF_MEMWORDS 16

#endif
