1/*
2 * Copyright (c) 1988, 1989, 1990, 1991, 1993, 1994
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that: (1) source code distributions
7 * retain the above copyright notice and this paragraph in its entirety, (2)
8 * distributions including binary code include the above copyright notice and
9 * this paragraph in its entirety in the documentation or other materials
10 * provided with the distribution, and (3) all advertising materials mentioning
11 * features or use of this software display the following acknowledgement:
12 * ``This product includes software developed by the University of California,
13 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
14 * the University nor the names of its contributors may be used to endorse
15 * or promote products derived from this software without specific prior
16 * written permission.
17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
18 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
20 */
21
22#ifndef lint
23static const char rcsid[] _U_ =
24    "@(#) $Header: /tcpdump/master/tcpdump/print-ipcomp.c,v 1.20 2003-11-19 00:36:08 guy Exp $";
25#endif
26
27#ifdef HAVE_CONFIG_H
28#include "config.h"
29#endif
30
31#include <string.h>
32#include <tcpdump-stdinc.h>
33
34#include <stdio.h>
35
36struct ipcomp {
37	u_int8_t comp_nxt;	/* Next Header */
38	u_int8_t comp_flags;	/* Length of data, in 32bit */
39	u_int16_t comp_cpi;	/* Compression parameter index */
40};
41
42#if defined(HAVE_LIBZ) && defined(HAVE_ZLIB_H)
43#include <zlib.h>
44#endif
45
46#include "interface.h"
47#include "addrtoname.h"
48#include "extract.h"
49
50int
51ipcomp_print(register const u_char *bp, int *nhdr _U_)
52{
53	register const struct ipcomp *ipcomp;
54	register const u_char *ep;
55	u_int16_t cpi;
56#if defined(HAVE_LIBZ) && defined(HAVE_ZLIB_H)
57	int advance;
58#endif
59
60	ipcomp = (struct ipcomp *)bp;
61	cpi = EXTRACT_16BITS(&ipcomp->comp_cpi);
62
63	/* 'ep' points to the end of available data. */
64	ep = snapend;
65
66	if ((u_char *)(ipcomp + 1) >= ep - sizeof(struct ipcomp)) {
67		fputs("[|IPCOMP]", stdout);
68		goto fail;
69	}
70	printf("IPComp(cpi=0x%04x)", cpi);
71
72#if defined(HAVE_LIBZ) && defined(HAVE_ZLIB_H)
73	if (1)
74		goto fail;
75
76	/*
77	 * We may want to decompress the packet here.  Packet buffer
78	 * management is a headache (if we decompress, packet will become
79	 * larger).
80	 */
81	if (nhdr)
82		*nhdr = ipcomp->comp_nxt;
83	advance = sizeof(struct ipcomp);
84
85	printf(": ");
86	return advance;
87
88#endif
89fail:
90	return -1;
91}
92