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 #include <sys/cdefs.h> 23 #ifndef lint 24 __RCSID("$NetBSD: print-chdlc.c,v 1.8 2017/02/05 04:05:05 spz Exp $"); 25 #endif 26 27 /* \summary: Cisco HDLC printer */ 28 29 #ifdef HAVE_CONFIG_H 30 #include "config.h" 31 #endif 32 33 #include <netdissect-stdinc.h> 34 35 #include "netdissect.h" 36 #include "addrtoname.h" 37 #include "ethertype.h" 38 #include "extract.h" 39 #include "chdlc.h" 40 41 static void chdlc_slarp_print(netdissect_options *, const u_char *, u_int); 42 43 static const struct tok chdlc_cast_values[] = { 44 { CHDLC_UNICAST, "unicast" }, 45 { CHDLC_BCAST, "bcast" }, 46 { 0, NULL} 47 }; 48 49 50 /* Standard CHDLC printer */ 51 u_int 52 chdlc_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h, register const u_char *p) 53 { 54 register u_int length = h->len; 55 register u_int caplen = h->caplen; 56 57 if (caplen < CHDLC_HDRLEN) { 58 ND_PRINT((ndo, "[|chdlc]")); 59 return (caplen); 60 } 61 return (chdlc_print(ndo, p,length)); 62 } 63 64 u_int 65 chdlc_print(netdissect_options *ndo, register const u_char *p, u_int length) 66 { 67 u_int proto; 68 69 proto = EXTRACT_16BITS(&p[2]); 70 if (ndo->ndo_eflag) { 71 ND_PRINT((ndo, "%s, ethertype %s (0x%04x), length %u: ", 72 tok2str(chdlc_cast_values, "0x%02x", p[0]), 73 tok2str(ethertype_values, "Unknown", proto), 74 proto, 75 length)); 76 } 77 78 length -= CHDLC_HDRLEN; 79 p += CHDLC_HDRLEN; 80 81 switch (proto) { 82 case ETHERTYPE_IP: 83 ip_print(ndo, p, length); 84 break; 85 case ETHERTYPE_IPV6: 86 ip6_print(ndo, p, length); 87 break; 88 case CHDLC_TYPE_SLARP: 89 chdlc_slarp_print(ndo, p, length); 90 break; 91 #if 0 92 case CHDLC_TYPE_CDP: 93 chdlc_cdp_print(p, length); 94 break; 95 #endif 96 case ETHERTYPE_MPLS: 97 case ETHERTYPE_MPLS_MULTI: 98 mpls_print(ndo, p, length); 99 break; 100 case ETHERTYPE_ISO: 101 /* is the fudge byte set ? lets verify by spotting ISO headers */ 102 if (*(p+1) == 0x81 || 103 *(p+1) == 0x82 || 104 *(p+1) == 0x83) 105 isoclns_print(ndo, p + 1, length - 1, ndo->ndo_snapend - p - 1); 106 else 107 isoclns_print(ndo, p, length, ndo->ndo_snapend - p); 108 break; 109 default: 110 if (!ndo->ndo_eflag) 111 ND_PRINT((ndo, "unknown CHDLC protocol (0x%04x)", proto)); 112 break; 113 } 114 115 return (CHDLC_HDRLEN); 116 } 117 118 /* 119 * The fixed-length portion of a SLARP packet. 120 */ 121 struct cisco_slarp { 122 uint8_t code[4]; 123 #define SLARP_REQUEST 0 124 #define SLARP_REPLY 1 125 #define SLARP_KEEPALIVE 2 126 union { 127 struct { 128 uint8_t addr[4]; 129 uint8_t mask[4]; 130 } addr; 131 struct { 132 uint8_t myseq[4]; 133 uint8_t yourseq[4]; 134 uint8_t rel[2]; 135 } keep; 136 } un; 137 }; 138 139 #define SLARP_MIN_LEN 14 140 #define SLARP_MAX_LEN 18 141 142 static void 143 chdlc_slarp_print(netdissect_options *ndo, const u_char *cp, u_int length) 144 { 145 const struct cisco_slarp *slarp; 146 u_int sec,min,hrs,days; 147 148 ND_PRINT((ndo, "SLARP (length: %u), ",length)); 149 if (length < SLARP_MIN_LEN) 150 goto trunc; 151 152 slarp = (const struct cisco_slarp *)cp; 153 ND_TCHECK2(*slarp, SLARP_MIN_LEN); 154 switch (EXTRACT_32BITS(&slarp->code)) { 155 case SLARP_REQUEST: 156 ND_PRINT((ndo, "request")); 157 /* 158 * At least according to William "Chops" Westfield's 159 * message in 160 * 161 * http://www.nethelp.no/net/cisco-hdlc.txt 162 * 163 * the address and mask aren't used in requests - 164 * they're just zero. 165 */ 166 break; 167 case SLARP_REPLY: 168 ND_PRINT((ndo, "reply %s/%s", 169 ipaddr_string(ndo, &slarp->un.addr.addr), 170 ipaddr_string(ndo, &slarp->un.addr.mask))); 171 break; 172 case SLARP_KEEPALIVE: 173 ND_PRINT((ndo, "keepalive: mineseen=0x%08x, yourseen=0x%08x, reliability=0x%04x", 174 EXTRACT_32BITS(&slarp->un.keep.myseq), 175 EXTRACT_32BITS(&slarp->un.keep.yourseq), 176 EXTRACT_16BITS(&slarp->un.keep.rel))); 177 178 if (length >= SLARP_MAX_LEN) { /* uptime-stamp is optional */ 179 cp += SLARP_MIN_LEN; 180 ND_TCHECK2(*cp, 4); 181 sec = EXTRACT_32BITS(cp) / 1000; 182 min = sec / 60; sec -= min * 60; 183 hrs = min / 60; min -= hrs * 60; 184 days = hrs / 24; hrs -= days * 24; 185 ND_PRINT((ndo, ", link uptime=%ud%uh%um%us",days,hrs,min,sec)); 186 } 187 break; 188 default: 189 ND_PRINT((ndo, "0x%02x unknown", EXTRACT_32BITS(&slarp->code))); 190 if (ndo->ndo_vflag <= 1) 191 print_unknown_data(ndo,cp+4,"\n\t",length-4); 192 break; 193 } 194 195 if (SLARP_MAX_LEN < length && ndo->ndo_vflag) 196 ND_PRINT((ndo, ", (trailing junk: %d bytes)", length - SLARP_MAX_LEN)); 197 if (ndo->ndo_vflag > 1) 198 print_unknown_data(ndo,cp+4,"\n\t",length-4); 199 return; 200 201 trunc: 202 ND_PRINT((ndo, "[|slarp]")); 203 } 204 205 206 /* 207 * Local Variables: 208 * c-style: whitesmith 209 * c-basic-offset: 8 210 * End: 211 */ 212