1 /* $OpenBSD: print-mobile.c,v 1.1 2000/01/16 11:20:14 jakob 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 * 3. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the NetBSD 22 * Foundation, Inc. and its contributors. 23 * 4. Neither the name of The NetBSD Foundation nor the names of its 24 * contributors may be used to endorse or promote products derived 25 * from this software without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 28 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 29 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 30 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 31 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 32 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 33 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 34 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 35 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 36 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 37 * POSSIBILITY OF SUCH DAMAGE. 38 */ 39 40 #if 0 41 #include <sys/cdefs.h> 42 #ifndef lint 43 __RCSID("$NetBSD: print-mobile.c,v 1.3 1999/07/26 06:11:57 itojun Exp $"); 44 #endif 45 #endif 46 47 #include <sys/param.h> 48 #include <sys/time.h> 49 #include <sys/uio.h> 50 #include <sys/socket.h> 51 52 #include <netinet/in.h> 53 #include <netinet/in_systm.h> 54 #include <netinet/ip.h> 55 56 #include <netdb.h> 57 #include <stdio.h> 58 59 #include "interface.h" 60 #include "addrtoname.h" 61 #include "extract.h" /* must come after interface.h */ 62 63 #define MOBILE_SIZE (8) 64 65 struct mobile_ip { 66 u_int16_t proto; 67 u_int16_t hcheck; 68 u_int32_t odst; 69 u_int32_t osrc; 70 }; 71 72 #define OSRC_PRES 0x0080 /* old source is present */ 73 74 static u_int16_t mob_in_cksum(u_short *p, int len); 75 76 /* 77 * Deencapsulate and print a mobile-tunneled IP datagram 78 */ 79 void 80 mobile_print(const u_char *bp, u_int length) 81 { 82 const u_char *cp = bp +8 ; 83 const struct mobile_ip *mob; 84 u_short proto,crc; 85 u_char osp =0; /* old source address present */ 86 87 mob = (const struct mobile_ip *)bp; 88 89 if (length < MOBILE_SIZE) { 90 fputs("[|mobile]", stdout); 91 return; 92 } 93 94 proto = EXTRACT_16BITS(&mob->proto); 95 crc = EXTRACT_16BITS(&mob->hcheck); 96 if (proto & OSRC_PRES) { 97 osp=1; 98 cp +=4 ; 99 } 100 101 if (osp) { 102 fputs("[S] ",stdout); 103 if (vflag) 104 (void)printf("%s ",ipaddr_string(&mob->osrc)); 105 } else { 106 fputs("[] ",stdout); 107 } 108 if (vflag) { 109 (void)printf("> %s ",ipaddr_string(&mob->odst)); 110 (void)printf("(oproto=%d)",proto>>8); 111 } 112 if (mob_in_cksum((u_short *)mob, osp ? 12 : 8)!=0) { 113 (void)printf(" (bad checksum %d)",crc); 114 } 115 116 return; 117 } 118 119 static u_int16_t mob_in_cksum(u_short *p, int len) 120 { 121 u_int32_t sum = 0; 122 int nwords = len >> 1; 123 124 while (nwords-- != 0) 125 sum += *p++; 126 127 if (len & 1) { 128 union { 129 u_int16_t w; 130 u_int32_t c[2]; 131 } u; 132 u.c[0] = *(u_char *)p; 133 u.c[1] = 0; 134 sum += u.w; 135 } 136 137 /* end-around-carry */ 138 sum = (sum >> 16) + (sum & 0xffff); 139 sum += (sum >> 16); 140 return (~sum); 141 } 142 143