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   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         register const u_char *ep;
  42         int sumlen;
  43         uint32_t spi;
  44
  45         ah = (const struct ah *)bp;
  46         ep = ndo->ndo_snapend;          /* 'ep' points to the end of available data. */
  47
  48         ND_TCHECK(*ah);
  49
  50         sumlen = ah->ah_len << 2;
  51         spi = EXTRACT_32BITS(&ah->ah_spi);
  52
  53         ND_PRINT((ndo, "AH(spi=0x%08x", spi));
  54         if (ndo->ndo_vflag)
  55                 ND_PRINT((ndo, ",sumlen=%d", sumlen));
  56         ND_PRINT((ndo, ",seq=0x%x", EXTRACT_32BITS(ah + 1)));
  57         if (bp + sizeof(struct ah) + sumlen > ep)
  58                 ND_PRINT((ndo, "[truncated]"));
  59         ND_PRINT((ndo, "): "));
  60
  61         return sizeof(struct ah) + sumlen;
  62  trunc:
  63         ND_PRINT((ndo, "[|AH]"));
  64         return -1;
  65 }