tcpdump/print-ah.c
guy fcc82f451d The "__attribute__((packed))" tag on structures causes some files not to
compile with Sun C, as "interface.h" isn't being included before the
structures are being declared.

Furthermore, in the files that Sun C *can* compile, it doesn't cause Sun
C to generate code that's safe with unaligned accesses, as
"__attribute__" is defined as a do-nothing macro with compilers that
don't support it.

Therefore, we get rid of that tag on the structures to which it was
added, and instead use "EXTRACT_16BIT()" and "EXTRACT_32BIT()" to fetch
16-bit and 32-bit big-endian quantities from packets.  We also fix some
other references to multi-byte quantities to get rid of code that tries
to do unaligned loads on platforms that don't support them.

We also throw in a hack that makes those macros use
"__attribute__((packed))" on structures containing only one 16-bit or
32-bit integer to get the compiler to generate unaligned-safe code
rather than doing it by hand.  (GCC on SPARC produces the same code that
doing it by hand does; I don't know if GCC on any other big-endian
strict-alignment processor generates better code for that case.  On
little-endian processors, as "ntohs()" and "ntohl()" might be functions,
that might actually produce worse code.)

Fix some places to use "%u" rather than "%d" to print unsigned
quantities.
2002-12-11 07:13:49 +00:00

72 lines
2.2 KiB
C

/* $NetBSD: print-ah.c,v 1.4 1996/05/20 00:41:16 fvdl Exp $ */
/*
* Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994
* 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.
*/
#ifndef lint
static const char rcsid[] =
"@(#) $Header: /tcpdump/master/tcpdump/print-ah.c,v 1.19 2002-12-11 07:13:57 guy Exp $ (LBL)";
#endif
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <tcpdump-stdinc.h>
#include <stdio.h>
#include "ah.h"
#include "interface.h"
#include "addrtoname.h"
#include "extract.h"
int
ah_print(register const u_char *bp)
{
register const struct ah *ah;
register const u_char *ep;
int sumlen;
u_int32_t spi;
ah = (const struct ah *)bp;
ep = snapend; /* 'ep' points to the end of available data. */
TCHECK(*ah);
sumlen = ah->ah_len << 2;
spi = EXTRACT_32BITS(&ah->ah_spi);
printf("AH(spi=0x%08x", spi);
if (vflag)
printf(",sumlen=%d", sumlen);
printf(",seq=0x%x", EXTRACT_32BITS(ah + 1));
if (bp + sizeof(struct ah) + sumlen > ep)
fputs("[truncated]", stdout);
fputs("): ", stdout);
return sizeof(struct ah) + sumlen;
trunc:
fputs("[|AH]", stdout);
return 65535;
}