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   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         nd_uint16_t proto;
  55         nd_uint16_t hcheck;
  56         nd_uint32_t odst;
  57         nd_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         ndo->ndo_protocol = "mobile";
  74         mob = (const struct mobile_ip *)bp;
  75
  76         if (length < MOBILE_SIZE || !ND_TTEST_SIZE(mob)) {
  77                 nd_print_trunc(ndo);
  78                 return;
  79         }
  80         ND_PRINT("mobile: ");
  81
  82         proto = GET_BE_U_2(mob->proto);
  83         crc =  GET_BE_U_2(mob->hcheck);
  84         if (proto & OSRC_PRES) {
  85                 osp=1;
  86         }
  87
  88         if (osp)  {
  89                 ND_PRINT("[S] ");
  90                 if (ndo->ndo_vflag)
  91                         ND_PRINT("%s ", GET_IPADDR_STRING(mob->osrc));
  92         } else {
  93                 ND_PRINT("[] ");
  94         }
  95         if (ndo->ndo_vflag) {
  96                 ND_PRINT("> %s ", GET_IPADDR_STRING(mob->odst));
  97                 ND_PRINT("(oproto=%u)", proto>>8);
  98         }
  99         vec[0].ptr = (const uint8_t *)(const void *)mob;
 100         vec[0].len = osp ? 12 : 8;
 101         if (in_cksum(vec, 1)!=0) {
 102                 ND_PRINT(" (bad checksum %u)", crc);
 103         }
 104 }