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