contrib/tcpdump-3.8.3/print-ipcomp.c

   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
  23 static const char rcsid[] _U_ =
  24     "@(#) $Header: /tcpdump/master/tcpdump/print-ipcomp.c,v 1.17.2.3 2003/11/19 00:35:45 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
  36 struct 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
  50 int
  51 ipcomp_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
  89 fail:
  90         return -1;
  91 }