contrib/tcpdump/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 /* \summary: IPv4 mobility printer */
  40
  41 #ifdef HAVE_CONFIG_H
  42 #include "config.h"
  43 #endif
  44
  45 #include <netdissect-stdinc.h>
  46
  47 #include "netdissect.h"
  48 #include "addrtoname.h"
  49 #include "extract.h"
  50
  51 #define MOBILE_SIZE (8)
  52
  53 struct mobile_ip {
  54         uint16_t proto;
  55         uint16_t hcheck;
  56         uint32_t odst;
  57         uint32_t osrc;
  58 };
  59
  60 #define OSRC_PRES       0x0080  /* old source is present */
  61
  62 /*
  63  * Deencapsulate and print a mobile-tunneled IP datagram
  64  */
  65 void
  66 mobile_print(netdissect_options *ndo, const u_char *bp, u_int length)
  67 {
  68         const struct mobile_ip *mob;
  69         struct cksum_vec vec[1];
  70         u_short proto,crc;
  71         u_char osp =0;                  /* old source address present */
  72
  73         mob = (const struct mobile_ip *)bp;
  74
  75         if (length < MOBILE_SIZE || !ND_TTEST(*mob)) {
  76                 ND_PRINT((ndo, "[|mobile]"));
  77                 return;
  78         }
  79         ND_PRINT((ndo, "mobile: "));
  80
  81         proto = EXTRACT_16BITS(&mob->proto);
  82         crc =  EXTRACT_16BITS(&mob->hcheck);
  83         if (proto & OSRC_PRES) {
  84                 osp=1;
  85         }
  86
  87         if (osp)  {
  88                 ND_PRINT((ndo, "[S] "));
  89                 if (ndo->ndo_vflag)
  90                         ND_PRINT((ndo, "%s ", ipaddr_string(ndo, &mob->osrc)));
  91         } else {
  92                 ND_PRINT((ndo, "[] "));
  93         }
  94         if (ndo->ndo_vflag) {
  95                 ND_PRINT((ndo, "> %s ", ipaddr_string(ndo, &mob->odst)));
  96                 ND_PRINT((ndo, "(oproto=%d)", proto>>8));
  97         }
  98         vec[0].ptr = (const uint8_t *)(const void *)mob;
  99         vec[0].len = osp ? 12 : 8;
 100         if (in_cksum(vec, 1)!=0) {
 101                 ND_PRINT((ndo, " (bad checksum %d)", crc));
 102         }
 103 }