bpf.h

You can download a packet sniffer which grabs packets from local interface and analyses headers. It

/*-
 * 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       7.1 (Berkeley) 5/7/91
 *
 * @(#) $Header: /usr/cvsroot/wpdpack/Include/NET/bpf.h,v 1.10 2003/04/04 11:15:08 degioanni Exp $ (LBL)
 */

#ifndef BPF_MAJOR_VERSION

#ifdef __cplusplus
extern "C" {
#endif

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

typedef	int bpf_int32;
typedef	u_int bpf_u_int32;

/*
 * Alignment macros.  BPF_WORDALIGN rounds up to the next 
 * even multiple of BPF_ALIGNMENT. 
 */
#ifndef __NetBSD__
#define BPF_ALIGNMENT sizeof(bpf_int32)
#else
#define BPF_ALIGNMENT sizeof(long)
#endif
#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 */
	bpf_u_int32	bh_caplen;	/* length of captured portion */
	bpf_u_int32	bh_datalen;	/* original length of packet */
	u_short		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.
 */
#if defined(KERNEL) || defined(_KERNEL)
#define SIZEOF_BPF_HDR 18
#endif

/*
 * Data-link level type codes.
 */

/*
 * These are the types that are the same on all platforms; on other
 * platforms, a <net/bpf.h> should be supplied that defines the additional
 * DLT_* codes appropriately for that platform (the BSDs, for example,
 * should not just pick up this version of "bpf.h"; they should also define
 * the additional DLT_* codes used by their kernels, as well as the values
 * defined here - and, if the values they use for particular DLT_ types
 * differ from those here, they should use their values, not the ones
 * here).
 */
#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, with BSD-style header */
#define DLT_SLIP	8	/* Serial Line IP */
#define DLT_PPP		9	/* Point-to-point Protocol */
#define DLT_FDDI	10	/* FDDI */

/*
 * These are values from the traditional libpcap "bpf.h".
 * Ports of this to particular platforms should replace these definitions
 * with the ones appropriate to that platform, if the values are
 * different on that platform.
 */
#define DLT_ATM_RFC1483	11	/* LLC/SNAP encapsulated atm */
#define DLT_RAW		12	/* raw IP */

/*
 * These are values from BSD/OS's "bpf.h".
 * These are not the same as the values from the traditional libpcap
 * "bpf.h"; however, these values shouldn't be generated by any
 * OS other than BSD/OS, so the correct values to use here are the
 * BSD/OS values.
 *
 * Platforms that have already assigned these values to other
 * DLT_ codes, however, should give these codes the values
 * from that platform, so that programs that use these codes will
 * continue to compile - even though they won't correctly read
 * files of these types.
 */
#ifdef __NetBSD__
#ifndef DLT_SLIP_BSDOS
#define DLT_SLIP_BSDOS	13	/* BSD/OS Serial Line IP */
#define DLT_PPP_BSDOS	14	/* BSD/OS Point-to-point Protocol */
#endif
#else
#define DLT_SLIP_BSDOS	15	/* BSD/OS Serial Line IP */
#define DLT_PPP_BSDOS	16	/* BSD/OS Point-to-point Protocol */
#endif

#define DLT_ATM_CLIP	19	/* Linux Classical-IP over ATM */

/*
 * These values are defined by NetBSD; other platforms should refrain from
 * using them for other purposes, so that NetBSD savefiles with link
 * types of 50 or 51 can be read as this type on all platforms.
 */
#define DLT_PPP_SERIAL	50	/* PPP over serial with HDLC encapsulation */
#define DLT_PPP_ETHER	51	/* PPP over Ethernet */

/*
 * Values between 100 and 103 are used in capture file headers as
 * link-layer types corresponding to DLT_ types that differ
 * between platforms; don't use those values for new DLT_ new types.
 */

/*
 * This value was defined by libpcap 0.5; platforms that have defined
 * it with a different value should define it here with that value -
 * a link type of 104 in a save file will be mapped to DLT_C_HDLC,
 * whatever value that happens to be, so programs will correctly
 * handle files with that link type regardless of the value of
 * DLT_C_HDLC.
 *
 * The name DLT_C_HDLC was used by BSD/OS; we use that name for source
 * compatibility with programs written for BSD/OS.
 *
 * libpcap 0.5 defined it as DLT_CHDLC; we define DLT_CHDLC as well,
 * for source compatibility with programs written for libpcap 0.5.
 */
#define DLT_C_HDLC	104	/* Cisco HDLC */
#define DLT_CHDLC	DLT_C_HDLC

#define DLT_IEEE802_11	105	/* IEEE 802.11 wireless */

/*
 * 106 is reserved for Linux Classical IP over ATM; it's like DLT_RAW,