The Tcpdump Group git mirrors - tcpdump/blob - print-mobile.c

   1 /*      $NetBSD: print-mobile.c,v 1.2 1998/09/30 08:57:01 hwr Exp $ */
   2
   3 /*
   4  * (c) 1998 The NetBSD Foundation, Inc.
   5  * All rights reserved.
   6  *
   7  * This code is derived from software contributed to The NetBSD Foundation
   8  * by Heiko W.Rupp <hwr@pilhuhn.de>
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 3. All advertising materials mentioning features or use of this software
  19  *    must display the following acknowledgement:
  20  *        This product includes software developed by the NetBSD
  21  *        Foundation, Inc. and its contributors.
  22  * 4. Neither the name of The NetBSD Foundation nor the names of its
  23  *    contributors may be used to endorse or promote products derived
  24  *    from this software without specific prior written permission.
  25  *
  26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  36  * POSSIBILITY OF SUCH DAMAGE.
  37  */
  38
  39 #ifdef HAVE_CONFIG_H
  40 #include "config.h"
  41 #endif
  42
  43 #include <tcpdump-stdinc.h>
  44
  45 #include "interface.h"
  46 #include "addrtoname.h"
  47 #include "extract.h"            /* must come after interface.h */
  48
  49 #define MOBILE_SIZE (8)
  50
  51 struct mobile_ip {
  52         uint16_t proto;
  53         uint16_t hcheck;
  54         uint32_t odst;
  55         uint32_t osrc;
  56 };
  57
  58 #define OSRC_PRES       0x0080  /* old source is present */
  59
  60 /*
  61  * Deencapsulate and print a mobile-tunneled IP datagram
  62  */
  63 void
  64 mobile_print(netdissect_options *ndo, const u_char *bp, u_int length)
  65 {
  66         const struct mobile_ip *mob;
  67         struct cksum_vec vec[1];
  68         u_short proto,crc;
  69         u_char osp =0;                  /* old source address present */
  70
  71         mob = (const struct mobile_ip *)bp;
  72
  73         if (length < MOBILE_SIZE || !ND_TTEST(*mob)) {
  74                 ND_PRINT((ndo, "[|mobile]"));
  75                 return;
  76         }
  77         ND_PRINT((ndo, "mobile: "));
  78
  79         proto = EXTRACT_16BITS(&mob->proto);
  80         crc =  EXTRACT_16BITS(&mob->hcheck);
  81         if (proto & OSRC_PRES) {
  82                 osp=1;
  83         }
  84
  85         if (osp)  {
  86                 ND_PRINT((ndo, "[S] "));
  87                 if (ndo->ndo_vflag)
  88                         ND_PRINT((ndo, "%s ", ipaddr_string(ndo, &mob->osrc)));
  89         } else {
  90                 ND_PRINT((ndo, "[] "));
  91         }
  92         if (ndo->ndo_vflag) {
  93                 ND_PRINT((ndo, "> %s ", ipaddr_string(ndo, &mob->odst)));
  94                 ND_PRINT((ndo, "(oproto=%d)", proto>>8));
  95         }
  96         vec[0].ptr = (const uint8_t *)(const void *)mob;
  97         vec[0].len = osp ? 12 : 8;
  98         if (in_cksum(vec, 1)!=0) {
  99                 ND_PRINT((ndo, " (bad checksum %d)", crc));
 100         }
 101 }