1 /* 2 * Copyright (c) 1990, 1991, 1993, 1994, 1995, 1996, 1997 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that: (1) source code distributions 7 * retain the above copyright notice and this paragraph in its entirety, (2) 8 * distributions including binary code include the above copyright notice and 9 * this paragraph in its entirety in the documentation or other materials 10 * provided with the distribution, and (3) all advertising materials mentioning 11 * features or use of this software display the following acknowledgement: 12 * ``This product includes software developed by the University of California, 13 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of 14 * the University nor the names of its contributors may be used to endorse 15 * or promote products derived from this software without specific prior 16 * written permission. 17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED 18 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF 19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. 20 */ 21 22 #ifndef lint 23 static const char rcsid[] _U_ = 24 "@(#) $Header: /tcpdump/master/tcpdump/print-chdlc.c,v 1.32.2.7 2005/04/27 14:35:56 hannes Exp $ (LBL)"; 25 #endif 26 27 #ifdef HAVE_CONFIG_H 28 #include "config.h" 29 #endif 30 31 #include <tcpdump-stdinc.h> 32 33 #include <pcap.h> 34 #include <stdio.h> 35 36 #include "interface.h" 37 #include "addrtoname.h" 38 #include "ethertype.h" 39 #include "extract.h" 40 #include "ppp.h" 41 #include "chdlc.h" 42 43 static void chdlc_slarp_print(const u_char *, u_int); 44 45 /* Standard CHDLC printer */ 46 u_int 47 chdlc_if_print(const struct pcap_pkthdr *h, register const u_char *p) 48 { 49 register u_int length = h->len; 50 register u_int caplen = h->caplen; 51 const struct ip *ip; 52 u_int proto; 53 54 if (caplen < CHDLC_HDRLEN) { 55 printf("[|chdlc]"); 56 return (caplen); 57 } 58 59 proto = EXTRACT_16BITS(&p[2]); 60 if (eflag) { 61 switch (p[0]) { 62 case CHDLC_UNICAST: 63 printf("unicast "); 64 break; 65 case CHDLC_BCAST: 66 printf("bcast "); 67 break; 68 default: 69 printf("0x%02x ", p[0]); 70 break; 71 } 72 printf("%d %04x: ", length, proto); 73 } 74 75 length -= CHDLC_HDRLEN; 76 ip = (const struct ip *)(p + CHDLC_HDRLEN); 77 switch (proto) { 78 case ETHERTYPE_IP: 79 ip_print(gndo, (const u_char *)ip, length); 80 break; 81 #ifdef INET6 82 case ETHERTYPE_IPV6: 83 ip6_print((const u_char *)ip, length); 84 break; 85 #endif 86 case CHDLC_TYPE_SLARP: 87 chdlc_slarp_print((const u_char *)ip, length); 88 break; 89 #if 0 90 case CHDLC_TYPE_CDP: 91 chdlc_cdp_print((const u_char *)ip, length); 92 break; 93 #endif 94 case ETHERTYPE_MPLS: 95 case ETHERTYPE_MPLS_MULTI: 96 mpls_print((const u_char *)(ip), length); 97 break; 98 case ETHERTYPE_ISO: 99 /* is the fudge byte set ? lets verify by spotting ISO headers */ 100 if (*(p+CHDLC_HDRLEN+1) == 0x81 || 101 *(p+CHDLC_HDRLEN+1) == 0x82 || 102 *(p+CHDLC_HDRLEN+1) == 0x83) 103 isoclns_print(p+CHDLC_HDRLEN+1, length-1, length-1); 104 else 105 isoclns_print(p+CHDLC_HDRLEN, length, length); 106 break; 107 default: 108 printf("unknown CHDLC protocol (0x%04x)", proto); 109 break; 110 } 111 112 return (CHDLC_HDRLEN); 113 } 114 115 /* 116 * The fixed-length portion of a SLARP packet. 117 */ 118 struct cisco_slarp { 119 u_int8_t code[4]; 120 #define SLARP_REQUEST 0 121 #define SLARP_REPLY 1 122 #define SLARP_KEEPALIVE 2 123 union { 124 struct { 125 u_int8_t addr[4]; 126 u_int8_t mask[4]; 127 } addr; 128 struct { 129 u_int8_t myseq[4]; 130 u_int8_t yourseq[4]; 131 u_int8_t rel[2]; 132 } keep; 133 } un; 134 }; 135 136 #define SLARP_MIN_LEN 14 137 #define SLARP_MAX_LEN 18 138 139 static void 140 chdlc_slarp_print(const u_char *cp, u_int length) 141 { 142 const struct cisco_slarp *slarp; 143 u_int sec,min,hrs,days; 144 145 printf("SLARP (length: %u), ",length); 146 if (length < SLARP_MIN_LEN) 147 goto trunc; 148 149 slarp = (const struct cisco_slarp *)cp; 150 TCHECK2(*slarp, SLARP_MIN_LEN); 151 switch (EXTRACT_32BITS(&slarp->code)) { 152 case SLARP_REQUEST: 153 printf("request"); 154 /* 155 * At least according to William "Chops" Westfield's 156 * message in 157 * 158 * http://www.nethelp.no/net/cisco-hdlc.txt 159 * 160 * the address and mask aren't used in requests - 161 * they're just zero. 162 */ 163 break; 164 case SLARP_REPLY: 165 printf("reply %s/%s", 166 ipaddr_string(&slarp->un.addr.addr), 167 ipaddr_string(&slarp->un.addr.mask)); 168 break; 169 case SLARP_KEEPALIVE: 170 printf("keepalive: mineseen=0x%08x, yourseen=0x%08x, reliability=0x%04x", 171 EXTRACT_32BITS(&slarp->un.keep.myseq), 172 EXTRACT_32BITS(&slarp->un.keep.yourseq), 173 EXTRACT_16BITS(&slarp->un.keep.rel)); 174 175 if (length >= SLARP_MAX_LEN) { /* uptime-stamp is optional */ 176 cp += SLARP_MIN_LEN; 177 if (!TTEST2(*cp, 4)) 178 goto trunc; 179 sec = EXTRACT_32BITS(cp) / 1000; 180 min = sec / 60; sec -= min * 60; 181 hrs = min / 60; min -= hrs * 60; 182 days = hrs / 24; hrs -= days * 24; 183 printf(", link uptime=%ud%uh%um%us",days,hrs,min,sec); 184 } 185 break; 186 default: 187 printf("0x%02x unknown", EXTRACT_32BITS(&slarp->code)); 188 if (vflag <= 1) 189 print_unknown_data(cp+4,"\n\t",length-4); 190 break; 191 } 192 193 if (SLARP_MAX_LEN < length && vflag) 194 printf(", (trailing junk: %d bytes)", length - SLARP_MAX_LEN); 195 if (vflag > 1) 196 print_unknown_data(cp+4,"\n\t",length-4); 197 return; 198 199 trunc: 200 printf("[|slarp]"); 201 } 202 203 204 /* 205 * Local Variables: 206 * c-style: whitesmith 207 * c-basic-offset: 8 208 * End: 209 */ 210