xref: /freebsd/contrib/tcpdump/print-ah.c (revision cddbc3b40812213ff00041f79174cac0be360a2a)
1 /*	$NetBSD: print-ah.c,v 1.4 1996/05/20 00:41:16 fvdl Exp $	*/
2 
3 /*
4  * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that: (1) source code distributions
9  * retain the above copyright notice and this paragraph in its entirety, (2)
10  * distributions including binary code include the above copyright notice and
11  * this paragraph in its entirety in the documentation or other materials
12  * provided with the distribution, and (3) all advertising materials mentioning
13  * features or use of this software display the following acknowledgement:
14  * ``This product includes software developed by the University of California,
15  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
16  * the University nor the names of its contributors may be used to endorse
17  * or promote products derived from this software without specific prior
18  * written permission.
19  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
20  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
21  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
22  */
23 
24 /* \summary: IPSEC Authentication Header printer */
25 
26 #ifdef HAVE_CONFIG_H
27 #include "config.h"
28 #endif
29 
30 #include <netdissect-stdinc.h>
31 
32 #include "ah.h"
33 
34 #include "netdissect.h"
35 #include "extract.h"
36 
37 int
38 ah_print(netdissect_options *ndo, register const u_char *bp)
39 {
40 	register const struct ah *ah;
41 	int sumlen;
42 
43 	ah = (const struct ah *)bp;
44 
45 	ND_TCHECK(*ah);
46 
47 	sumlen = ah->ah_len << 2;
48 
49 	ND_PRINT((ndo, "AH(spi=0x%08x", EXTRACT_32BITS(&ah->ah_spi)));
50 	if (ndo->ndo_vflag)
51 		ND_PRINT((ndo, ",sumlen=%d", sumlen));
52 	ND_TCHECK_32BITS(ah + 1);
53 	ND_PRINT((ndo, ",seq=0x%x", EXTRACT_32BITS(ah + 1)));
54 	if (!ND_TTEST2(*bp, sizeof(struct ah) + sumlen)) {
55 		ND_PRINT((ndo, "[truncated]):"));
56 		return -1;
57 	}
58 	ND_PRINT((ndo, "): "));
59 
60 	return sizeof(struct ah) + sumlen;
61  trunc:
62 	ND_PRINT((ndo, "[|AH]"));
63 	return -1;
64 }
65