source: rtems-libbsd/freebsd/contrib/tcpdump/print-null.c @ 084d4db

#include <machine/rtems-bsd-user-space.h>

/*
 * Copyright (c) 1991, 1993, 1994, 1995, 1996, 1997
 *      The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that: (1) source code distributions
 * retain the above copyright notice and this paragraph in its entirety, (2)
 * distributions including binary code include the above copyright notice and
 * this paragraph in its entirety in the documentation or other materials
 * provided with the distribution, and (3) all advertising materials mentioning
 * features or use of this software display the following acknowledgement:
 * ``This product includes software developed by the University of California,
 * Lawrence Berkeley Laboratory and its contributors.'' 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 ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 *
 * $FreeBSD$
 */

#ifndef lint
static const char rcsid[] _U_ =
    "@(#) $Header: /tcpdump/master/tcpdump/print-null.c,v 1.57 2006-03-23 14:58:44 hannes Exp $ (LBL)";
#endif

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <tcpdump-stdinc.h>

#include <pcap.h>
#include <stdio.h>
#include <string.h>

#include "interface.h"
#include "addrtoname.h"

#include "ip.h"
#ifdef INET6
#include "ip6.h"
#endif
#include "af.h"

/*
 * The DLT_NULL packet header is 4 bytes long. It contains a host-byte-order
 * 32-bit integer that specifies the family, e.g. AF_INET.
 *
 * Note here that "host" refers to the host on which the packets were
 * captured; that isn't necessarily *this* host.
 *
 * The OpenBSD DLT_LOOP packet header is the same, except that the integer
 * is in network byte order.
 */
#define NULL_HDRLEN 4

/*
 * Byte-swap a 32-bit number.
 * ("htonl()" or "ntohl()" won't work - we want to byte-swap even on
 * big-endian platforms.)
 */
#define SWAPLONG(y) \
((((y)&0xff)<<24) | (((y)&0xff00)<<8) | (((y)&0xff0000)>>8) | (((y)>>24)&0xff))

static inline void
null_hdr_print(u_int family, u_int length)
{
        if (!qflag) {
                (void)printf("AF %s (%u)",
                        tok2str(bsd_af_values,"Unknown",family),family);
        } else {
                (void)printf("%s",
                        tok2str(bsd_af_values,"Unknown AF %u",family));
        }

        (void)printf(", length %u: ", length);
}

/*
 * This is the top level routine of the printer.  'p' points
 * to the ether header of the packet, 'h->ts' is the timestamp,
 * 'h->len' is the length of the packet off the wire, and 'h->caplen'
 * is the number of bytes actually captured.
 */
u_int
null_if_print(const struct pcap_pkthdr *h, const u_char *p)
{
        u_int length = h->len;
        u_int caplen = h->caplen;
        u_int family;

        if (caplen < NULL_HDRLEN) {
                printf("[|null]");
                return (NULL_HDRLEN);
        }

        memcpy((char *)&family, (char *)p, sizeof(family));

        /*
         * This isn't necessarily in our host byte order; if this is
         * a DLT_LOOP capture, it's in network byte order, and if
         * this is a DLT_NULL capture from a machine with the opposite
         * byte-order, it's in the opposite byte order from ours.
         *
         * If the upper 16 bits aren't all zero, assume it's byte-swapped.
         */
        if ((family & 0xFFFF0000) != 0)
                family = SWAPLONG(family);

        if (eflag)
                null_hdr_print(family, length);

        length -= NULL_HDRLEN;
        caplen -= NULL_HDRLEN;
        p += NULL_HDRLEN;

        switch (family) {

        case BSD_AFNUM_INET:
                ip_print(gndo, p, length);
                break;

#ifdef INET6
        case BSD_AFNUM_INET6_BSD:
        case BSD_AFNUM_INET6_FREEBSD:
        case BSD_AFNUM_INET6_DARWIN:
                ip6_print(gndo, p, length);
                break;
#endif

        case BSD_AFNUM_ISO:
                isoclns_print(p, length, caplen);
                break;

        case BSD_AFNUM_APPLETALK:
                atalk_print(p, length);
                break;

        case BSD_AFNUM_IPX:
                ipx_print(p, length);
                break;

        default:
                /* unknown AF_ value */
                if (!eflag)
                        null_hdr_print(family, length + NULL_HDRLEN);
                if (!suppress_default_print)
                        default_print(p, caplen);
        }

        return (NULL_HDRLEN);
}

/*
 * Local Variables:
 * c-style: whitesmith
 * c-basic-offset: 8
 * End:
 */