The Tcpdump Group git mirrors - tcpdump/blob - 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[] =
  24     "@(#) $Header: /tcpdump/master/tcpdump/print-ipcomp.c,v 1.14 2002-08-01 08:53:11 risso 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
  49 int
  50 ipcomp_print(register const u_char *bp, register const u_char *bp2, int *nhdr)
  51 {
  52         register const struct ipcomp *ipcomp;
  53         register const u_char *ep;
  54         u_int16_t cpi;
  55 #if defined(HAVE_LIBZ) && defined(HAVE_ZLIB_H)
  56         int advance;
  57 #endif
  58
  59         ipcomp = (struct ipcomp *)bp;
  60         cpi = (u_int16_t)ntohs(ipcomp->comp_cpi);
  61
  62         /* 'ep' points to the end of available data. */
  63         ep = snapend;
  64
  65         if ((u_char *)(ipcomp + 1) >= ep - sizeof(struct ipcomp)) {
  66                 fputs("[|IPCOMP]", stdout);
  67                 goto fail;
  68         }
  69         printf("IPComp(cpi=0x%04x)", cpi);
  70
  71 #if defined(HAVE_LIBZ) && defined(HAVE_ZLIB_H)
  72         if (1)
  73                 goto fail;
  74
  75         /*
  76          * We may want to decompress the packet here.  Packet buffer
  77          * management is a headache (if we decompress, packet will become
  78          * larger).
  79          */
  80         if (nhdr)
  81                 *nhdr = ipcomp->comp_nxt;
  82         advance = sizeof(struct ipcomp);
  83
  84         printf(": ");
  85         return advance;
  86
  87 #endif
  88 fail:
  89         if (nhdr)
  90                 *nhdr = -1;
  91         return 65536;
  92 }