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 #include <sys/cdefs.h>
23 #ifndef lint
24 __RCSID("$NetBSD: print-ipcomp.c,v 1.4 2014/11/20 03:05:03 christos Exp $");
25 #endif
26
27 #define NETDISSECT_REWORKED
28 #ifdef HAVE_CONFIG_H
29 #include "config.h"
30 #endif
31
32 #include <tcpdump-stdinc.h>
33
34 struct ipcomp {
35 uint8_t comp_nxt; /* Next Header */
36 uint8_t comp_flags; /* Length of data, in 32bit */
37 uint16_t comp_cpi; /* Compression parameter index */
38 };
39
40 #if defined(HAVE_LIBZ) && defined(HAVE_ZLIB_H)
41 #include <zlib.h>
42 #endif
43
44 #include "interface.h"
45 #include "extract.h"
46
47 int
ipcomp_print(netdissect_options * ndo,register const u_char * bp,int * nhdr _U_)48 ipcomp_print(netdissect_options *ndo, register const u_char *bp, int *nhdr _U_)
49 {
50 register const struct ipcomp *ipcomp;
51 register const u_char *ep;
52 uint16_t cpi;
53 #if defined(HAVE_LIBZ) && defined(HAVE_ZLIB_H)
54 int advance;
55 #endif
56
57 ipcomp = (struct ipcomp *)bp;
58 cpi = EXTRACT_16BITS(&ipcomp->comp_cpi);
59
60 /* 'ep' points to the end of available data. */
61 ep = ndo->ndo_snapend;
62
63 if ((u_char *)(ipcomp + 1) >= ep - sizeof(struct ipcomp)) {
64 ND_PRINT((ndo, "[|IPCOMP]"));
65 goto fail;
66 }
67 ND_PRINT((ndo, "IPComp(cpi=0x%04x)", cpi));
68
69 #if defined(HAVE_LIBZ) && defined(HAVE_ZLIB_H)
70 if (1)
71 goto fail;
72
73 /*
74 * We may want to decompress the packet here. Packet buffer
75 * management is a headache (if we decompress, packet will become
76 * larger).
77 */
78 if (nhdr)
79 *nhdr = ipcomp->comp_nxt;
80 advance = sizeof(struct ipcomp);
81
82 ND_PRINT((ndo, ": "));
83 return advance;
84
85 #endif
86 fail:
87 return -1;
88 }
89