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 1.9 2017/09/08 14:01:13 christos 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 return chdlc_print(ndo, p, h->len); 55 } 56 57 u_int 58 chdlc_print(netdissect_options *ndo, register const u_char *p, u_int length) 59 { 60 u_int proto; 61 const u_char *bp = p; 62 63 if (length < CHDLC_HDRLEN) 64 goto trunc; 65 ND_TCHECK2(*p, CHDLC_HDRLEN); 66 proto = EXTRACT_16BITS(&p[2]); 67 if (ndo->ndo_eflag) { 68 ND_PRINT((ndo, "%s, ethertype %s (0x%04x), length %u: ", 69 tok2str(chdlc_cast_values, "0x%02x", p[0]), 70 tok2str(ethertype_values, "Unknown", proto), 71 proto, 72 length)); 73 } 74 75 length -= CHDLC_HDRLEN; 76 p += CHDLC_HDRLEN; 77 78 switch (proto) { 79 case ETHERTYPE_IP: 80 ip_print(ndo, p, length); 81 break; 82 case ETHERTYPE_IPV6: 83 ip6_print(ndo, p, length); 84 break; 85 case CHDLC_TYPE_SLARP: 86 chdlc_slarp_print(ndo, p, length); 87 break; 88 #if 0 89 case CHDLC_TYPE_CDP: 90 chdlc_cdp_print(p, length); 91 break; 92 #endif 93 case ETHERTYPE_MPLS: 94 case ETHERTYPE_MPLS_MULTI: 95 mpls_print(ndo, p, length); 96 break; 97 case ETHERTYPE_ISO: 98 /* is the fudge byte set ? lets verify by spotting ISO headers */ 99 if (length < 2) 100 goto trunc; 101 ND_TCHECK_16BITS(p); 102 if (*(p+1) == 0x81 || 103 *(p+1) == 0x82 || 104 *(p+1) == 0x83) 105 isoclns_print(ndo, p + 1, length - 1); 106 else 107 isoclns_print(ndo, p, length); 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 trunc: 118 ND_PRINT((ndo, "[|chdlc]")); 119 return ndo->ndo_snapend - bp; 120 } 121 122 /* 123 * The fixed-length portion of a SLARP packet. 124 */ 125 struct cisco_slarp { 126 uint8_t code[4]; 127 #define SLARP_REQUEST 0 128 #define SLARP_REPLY 1 129 #define SLARP_KEEPALIVE 2 130 union { 131 struct { 132 uint8_t addr[4]; 133 uint8_t mask[4]; 134 } addr; 135 struct { 136 uint8_t myseq[4]; 137 uint8_t yourseq[4]; 138 uint8_t rel[2]; 139 } keep; 140 } un; 141 }; 142 143 #define SLARP_MIN_LEN 14 144 #define SLARP_MAX_LEN 18 145 146 static void 147 chdlc_slarp_print(netdissect_options *ndo, const u_char *cp, u_int length) 148 { 149 const struct cisco_slarp *slarp; 150 u_int sec,min,hrs,days; 151 152 ND_PRINT((ndo, "SLARP (length: %u), ",length)); 153 if (length < SLARP_MIN_LEN) 154 goto trunc; 155 156 slarp = (const struct cisco_slarp *)cp; 157 ND_TCHECK2(*slarp, SLARP_MIN_LEN); 158 switch (EXTRACT_32BITS(&slarp->code)) { 159 case SLARP_REQUEST: 160 ND_PRINT((ndo, "request")); 161 /* 162 * At least according to William "Chops" Westfield's 163 * message in 164 * 165 * http://www.nethelp.no/net/cisco-hdlc.txt 166 * 167 * the address and mask aren't used in requests - 168 * they're just zero. 169 */ 170 break; 171 case SLARP_REPLY: 172 ND_PRINT((ndo, "reply %s/%s", 173 ipaddr_string(ndo, &slarp->un.addr.addr), 174 ipaddr_string(ndo, &slarp->un.addr.mask))); 175 break; 176 case SLARP_KEEPALIVE: 177 ND_PRINT((ndo, "keepalive: mineseen=0x%08x, yourseen=0x%08x, reliability=0x%04x", 178 EXTRACT_32BITS(&slarp->un.keep.myseq), 179 EXTRACT_32BITS(&slarp->un.keep.yourseq), 180 EXTRACT_16BITS(&slarp->un.keep.rel))); 181 182 if (length >= SLARP_MAX_LEN) { /* uptime-stamp is optional */ 183 cp += SLARP_MIN_LEN; 184 ND_TCHECK2(*cp, 4); 185 sec = EXTRACT_32BITS(cp) / 1000; 186 min = sec / 60; sec -= min * 60; 187 hrs = min / 60; min -= hrs * 60; 188 days = hrs / 24; hrs -= days * 24; 189 ND_PRINT((ndo, ", link uptime=%ud%uh%um%us",days,hrs,min,sec)); 190 } 191 break; 192 default: 193 ND_PRINT((ndo, "0x%02x unknown", EXTRACT_32BITS(&slarp->code))); 194 if (ndo->ndo_vflag <= 1) 195 print_unknown_data(ndo,cp+4,"\n\t",length-4); 196 break; 197 } 198 199 if (SLARP_MAX_LEN < length && ndo->ndo_vflag) 200 ND_PRINT((ndo, ", (trailing junk: %d bytes)", length - SLARP_MAX_LEN)); 201 if (ndo->ndo_vflag > 1) 202 print_unknown_data(ndo,cp+4,"\n\t",length-4); 203 return; 204 205 trunc: 206 ND_PRINT((ndo, "[|slarp]")); 207 } 208 209 210 /* 211 * Local Variables: 212 * c-style: whitesmith 213 * c-basic-offset: 8 214 * End: 215 */ 216