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/*
* 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.
*/
/* \summary: BSD loopback device printer */
#include <config.h>
#include "netdissect-stdinc.h"
#define ND_LONGJMP_FROM_TCHECK
#include "netdissect.h"
#include "extract.h"
#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 void
null_hdr_print(netdissect_options *ndo, uint32_t family, u_int length)
{
if (!ndo->ndo_qflag) {
ND_PRINT("AF %s (%u)",
tok2str(bsd_af_values,"Unknown",family),family);
} else {
ND_PRINT("%s",
tok2str(bsd_af_values,"Unknown AF %u",family));
}
ND_PRINT(", 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.
*/
void
null_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h, const u_char *p)
{
u_int length = h->len;
u_int caplen = h->caplen;
uint32_t family;
ndo->ndo_protocol = "null";
ND_TCHECK_LEN(p, NULL_HDRLEN);
ndo->ndo_ll_hdr_len += NULL_HDRLEN;
family = GET_HE_U_4(p);
/*
* 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 (ndo->ndo_eflag)
null_hdr_print(ndo, family, length);
length -= NULL_HDRLEN;
caplen -= NULL_HDRLEN;
p += NULL_HDRLEN;
switch (family) {
case BSD_AFNUM_INET:
ip_print(ndo, p, length);
break;
case BSD_AFNUM_INET6_BSD:
case BSD_AFNUM_INET6_FREEBSD:
case BSD_AFNUM_INET6_DARWIN:
ip6_print(ndo, p, length);
break;
case BSD_AFNUM_ISO:
isoclns_print(ndo, p, length);
break;
case BSD_AFNUM_APPLETALK:
atalk_print(ndo, p, length);
break;
case BSD_AFNUM_IPX:
ipx_print(ndo, p, length);
break;
default:
/* unknown AF_ value */
if (!ndo->ndo_eflag)
null_hdr_print(ndo, family, length + NULL_HDRLEN);
if (!ndo->ndo_suppress_default_print)
ND_DEFAULTPRINT(p, caplen);
}
}
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