1 /* $OpenBSD: print-mobile.c,v 1.2 2008/06/27 06:03:08 ray Exp $ */ 2 /* $NetBSD: print-mobile.c,v 1.3 1999/07/26 06:11:57 itojun Exp $ */ 3 4 /* 5 * (c) 1998 The NetBSD Foundation, Inc. 6 * All rights reserved. 7 * 8 * This code is derived from software contributed to The NetBSD Foundation 9 * by Heiko W.Rupp <hwr@pilhuhn.de> 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 30 * POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 #if 0 34 #include <sys/cdefs.h> 35 #ifndef lint 36 __RCSID("$NetBSD: print-mobile.c,v 1.3 1999/07/26 06:11:57 itojun Exp $"); 37 #endif 38 #endif 39 40 #include <sys/param.h> 41 #include <sys/time.h> 42 #include <sys/uio.h> 43 #include <sys/socket.h> 44 45 #include <netinet/in.h> 46 #include <netinet/in_systm.h> 47 #include <netinet/ip.h> 48 49 #include <netdb.h> 50 #include <stdio.h> 51 52 #include "interface.h" 53 #include "addrtoname.h" 54 #include "extract.h" /* must come after interface.h */ 55 56 #define MOBILE_SIZE (8) 57 58 struct mobile_ip { 59 u_int16_t proto; 60 u_int16_t hcheck; 61 u_int32_t odst; 62 u_int32_t osrc; 63 }; 64 65 #define OSRC_PRES 0x0080 /* old source is present */ 66 67 static u_int16_t mob_in_cksum(u_short *p, int len); 68 69 /* 70 * Deencapsulate and print a mobile-tunneled IP datagram 71 */ 72 void 73 mobile_print(const u_char *bp, u_int length) 74 { 75 const u_char *cp = bp +8 ; 76 const struct mobile_ip *mob; 77 u_short proto,crc; 78 u_char osp =0; /* old source address present */ 79 80 mob = (const struct mobile_ip *)bp; 81 82 if (length < MOBILE_SIZE) { 83 fputs("[|mobile]", stdout); 84 return; 85 } 86 87 proto = EXTRACT_16BITS(&mob->proto); 88 crc = EXTRACT_16BITS(&mob->hcheck); 89 if (proto & OSRC_PRES) { 90 osp=1; 91 cp +=4 ; 92 } 93 94 if (osp) { 95 fputs("[S] ",stdout); 96 if (vflag) 97 (void)printf("%s ",ipaddr_string(&mob->osrc)); 98 } else { 99 fputs("[] ",stdout); 100 } 101 if (vflag) { 102 (void)printf("> %s ",ipaddr_string(&mob->odst)); 103 (void)printf("(oproto=%d)",proto>>8); 104 } 105 if (mob_in_cksum((u_short *)mob, osp ? 12 : 8)!=0) { 106 (void)printf(" (bad checksum %d)",crc); 107 } 108 109 return; 110 } 111 112 static u_int16_t mob_in_cksum(u_short *p, int len) 113 { 114 u_int32_t sum = 0; 115 int nwords = len >> 1; 116 117 while (nwords-- != 0) 118 sum += *p++; 119 120 if (len & 1) { 121 union { 122 u_int16_t w; 123 u_int32_t c[2]; 124 } u; 125 u.c[0] = *(u_char *)p; 126 u.c[1] = 0; 127 sum += u.w; 128 } 129 130 /* end-around-carry */ 131 sum = (sum >> 16) + (sum & 0xffff); 132 sum += (sum >> 16); 133 return (~sum); 134 } 135 136