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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 (at) 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 }
    104