1 /* 2 * Copyright (c) 1992, 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 * Code by Gert Doering, SpaceNet GmbH, gert@space.net 22 * 23 * Reference documentation: 24 * http://www.cisco.com/univercd/cc/td/doc/product/lan/trsrb/frames.htm 25 */ 26 27 #ifndef lint 28 static const char rcsid[] _U_ = 29 "@(#) $Header: /tcpdump/master/tcpdump/print-cdp.c,v 1.25 2004/10/07 14:53:11 hannes Exp $"; 30 #endif 31 32 #ifdef HAVE_CONFIG_H 33 #include "config.h" 34 #endif 35 36 #include <tcpdump-stdinc.h> 37 38 #include <stdio.h> 39 #include <string.h> 40 41 #include "interface.h" 42 #include "addrtoname.h" 43 #include "extract.h" /* must come after interface.h */ 44 #include "nlpid.h" 45 46 #define CDP_HEADER_LEN 4 47 48 static struct tok cdp_tlv_values[] = { 49 { 0x01, "Device-ID"}, 50 { 0x02, "Address"}, 51 { 0x03, "Port-ID"}, 52 { 0x04, "Capability"}, 53 { 0x05, "Version String"}, 54 { 0x06, "Platform"}, 55 { 0x07, "Prefixes"}, 56 { 0x08, "Protocol-Hello option"}, 57 { 0x09, "VTP Management Domain"}, 58 { 0x0a, "Native VLAN ID"}, 59 { 0x0b, "Duplex"}, 60 { 0x0e, "ATA-186 VoIP VLAN request"}, 61 { 0x0f, "ATA-186 VoIP VLAN assignment"}, 62 { 0x10, "power consumption"}, 63 { 0x11, "MTU"}, 64 { 0x12, "AVVID trust bitmap"}, 65 { 0x13, "AVVID untrusted ports CoS"}, 66 { 0x14, "System Name"}, 67 { 0x15, "System Object ID (not decoded)"}, 68 { 0x16, "Management Addresses"}, 69 { 0x17, "Physical Location"}, 70 { 0, NULL} 71 }; 72 73 static struct tok cdp_capability_values[] = { 74 { 0x01, "Router" }, 75 { 0x02, "Transparent Bridge" }, 76 { 0x04, "Source Route Bridge" }, 77 { 0x08, "L2 Switch" }, 78 { 0x10, "L3 capable" }, 79 { 0x20, "IGMP snooping" }, 80 { 0x40, "L1 capable" }, 81 { 0, NULL } 82 }; 83 84 static int cdp_print_addr(const u_char *, int); 85 static int cdp_print_prefixes(const u_char *, int); 86 static unsigned long cdp_get_number(const u_char *, int); 87 88 void 89 cdp_print(const u_char *pptr, u_int length, u_int caplen) 90 { 91 int type, len, i, j; 92 const u_char *tptr; 93 94 if (caplen < CDP_HEADER_LEN) { 95 (void)printf("[|cdp]"); 96 return; 97 } 98 99 tptr = pptr; /* temporary pointer */ 100 101 if (!TTEST2(*tptr, CDP_HEADER_LEN)) 102 goto trunc; 103 printf("CDPv%u, ttl: %us", *tptr, *(tptr+1)); 104 if (vflag) 105 printf(", checksum: %u (unverified), length %u", EXTRACT_16BITS(tptr), length); 106 tptr += CDP_HEADER_LEN; 107 108 while (tptr < (pptr+length)) { 109 110 if (!TTEST2(*tptr, 4)) /* read out Type and Length */ 111 goto trunc; 112 type = EXTRACT_16BITS(tptr); 113 len = EXTRACT_16BITS(tptr+2); /* object length includes the 4 bytes header length */ 114 tptr += 4; 115 len -= 4; 116 117 if (!TTEST2(*tptr, len)) 118 goto trunc; 119 120 if (vflag || type == 1) { /* in non-verbose mode just print Device-ID */ 121 122 if (vflag) 123 printf("\n\t%s (0x%02x), length: %u byte%s: ", 124 tok2str(cdp_tlv_values,"unknown field type", type), 125 type, 126 len, 127 len>1 ? "s" : ""); /* plural */ 128 129 switch (type) { 130 131 case 0x01: /* Device-ID */ 132 if (!vflag) 133 printf(", Device-ID '%.*s'", len, tptr); 134 else 135 printf("'%.*s'", len, tptr); 136 break; 137 case 0x02: /* Address */ 138 if (cdp_print_addr(tptr, len) < 0) 139 goto trunc; 140 break; 141 case 0x03: /* Port-ID */ 142 printf("'%.*s'", len, tptr); 143 break; 144 case 0x04: /* Capabilities */ 145 printf("(0x%08x): %s", 146 EXTRACT_32BITS(tptr), 147 bittok2str(cdp_capability_values, "none",EXTRACT_32BITS(tptr))); 148 break; 149 case 0x05: /* Version */ 150 printf("\n\t "); 151 for (i=0;i<len;i++) { 152 j = *(tptr+i); 153 putchar(j); 154 if (j == 0x0a) /* lets rework the version string to get a nice identation */ 155 printf("\t "); 156 } 157 break; 158 case 0x06: /* Platform */ 159 printf("'%.*s'", len, tptr); 160 break; 161 case 0x07: /* Prefixes */ 162 if (cdp_print_prefixes(tptr, len) < 0) 163 goto trunc; 164 break; 165 case 0x08: /* Protocol Hello Option - not documented */ 166 break; 167 case 0x09: /* VTP Mgmt Domain - not documented */ 168 printf("'%.*s'", len,tptr); 169 break; 170 case 0x0a: /* Native VLAN ID - not documented */ 171 printf("%d",EXTRACT_16BITS(tptr)); 172 break; 173 case 0x0b: /* Duplex - not documented */ 174 printf("%s", *(tptr) ? "full": "half"); 175 break; 176 177 /* http://www.cisco.com/univercd/cc/td/doc/product/voice/ata/atarn/186rn21m.htm 178 * plus more details from other sources 179 */ 180 case 0x0e: /* ATA-186 VoIP VLAN request - incomplete doc. */ 181 printf("app %d, vlan %d", 182 *(tptr), EXTRACT_16BITS(tptr+1)); 183 break; 184 case 0x10: /* ATA-186 VoIP VLAN assignment - incomplete doc. */ 185 printf("%1.2fW", 186 cdp_get_number(tptr, len)/1000.0 ); 187 break; 188 case 0x11: /* MTU - not documented */ 189 printf("%u bytes", EXTRACT_32BITS(tptr)); 190 break; 191 case 0x12: /* AVVID trust bitmap - not documented */ 192 printf("0x%02x", *(tptr) ); 193 break; 194 case 0x13: /* AVVID untrusted port CoS - not documented */ 195 printf("0x%02x", *(tptr)); 196 break; 197 case 0x14: /* System Name - not documented */ 198 printf("'%.*s'", len, tptr); 199 break; 200 case 0x16: /* System Object ID - not documented */ 201 if (cdp_print_addr(tptr, len) < 0) 202 goto trunc; 203 break; 204 case 0x17: /* Physical Location - not documented */ 205 printf("0x%02x/%.*s", *(tptr), len - 1, tptr + 1 ); 206 break; 207 default: 208 print_unknown_data(tptr,"\n\t ",len); 209 break; 210 } 211 } 212 /* avoid infinite loop */ 213 if (len == 0) 214 break; 215 tptr = tptr+len; 216 } 217 if (vflag < 1) 218 printf(", length %u",caplen); 219 220 return; 221 trunc: 222 printf("[|cdp]"); 223 } 224 225 /* 226 * Protocol type values. 227 * 228 * PT_NLPID means that the protocol type field contains an OSI NLPID. 229 * 230 * PT_IEEE_802_2 means that the protocol type field contains an IEEE 802.2 231 * LLC header that specifies that the payload is for that protocol. 232 */ 233 #define PT_NLPID 1 /* OSI NLPID */ 234 #define PT_IEEE_802_2 2 /* IEEE 802.2 LLC header */ 235 236 static int 237 cdp_print_addr(const u_char * p, int l) 238 { 239 int pt, pl, al, num; 240 const u_char *endp = p + l; 241 #ifdef INET6 242 static u_char prot_ipv6[] = { 243 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00, 0x86, 0xdd 244 }; 245 #endif 246 247 TCHECK2(*p, 2); 248 num = EXTRACT_32BITS(p); 249 p += 4; 250 251 while (p < endp && num >= 0) { 252 TCHECK2(*p, 2); 253 if (p + 2 > endp) 254 goto trunc; 255 pt = p[0]; /* type of "protocol" field */ 256 pl = p[1]; /* length of "protocol" field */ 257 p += 2; 258 259 TCHECK2(p[pl], 2); 260 if (p + pl + 2 > endp) 261 goto trunc; 262 al = EXTRACT_16BITS(&p[pl]); /* address length */ 263 264 if (pt == PT_NLPID && pl == 1 && *p == NLPID_IP && al == 4) { 265 /* 266 * IPv4: protocol type = NLPID, protocol length = 1 267 * (1-byte NLPID), protocol = 0xcc (NLPID for IPv4), 268 * address length = 4 269 */ 270 p += 3; 271 272 TCHECK2(*p, 4); 273 if (p + 4 > endp) 274 goto trunc; 275 printf("IPv4 (%u) %s", 276 num, 277 ipaddr_string(p)); 278 p += 4; 279 } 280 #ifdef INET6 281 else if (pt == PT_IEEE_802_2 && pl == 8 && 282 memcmp(p, prot_ipv6, 8) == 0 && al == 16) { 283 /* 284 * IPv6: protocol type = IEEE 802.2 header, 285 * protocol length = 8 (size of LLC+SNAP header), 286 * protocol = LLC+SNAP header with the IPv6 287 * Ethertype, address length = 16 288 */ 289 p += 10; 290 TCHECK2(*p, al); 291 if (p + al > endp) 292 goto trunc; 293 294 printf("IPv6 (%u) %s", 295 num, 296 ip6addr_string(p)); 297 p += al; 298 } 299 #endif 300 else { 301 /* 302 * Generic case: just print raw data 303 */ 304 TCHECK2(*p, pl); 305 if (p + pl > endp) 306 goto trunc; 307 printf("pt=0x%02x, pl=%d, pb=", *(p - 2), pl); 308 while (pl-- > 0) 309 printf(" %02x", *p++); 310 TCHECK2(*p, 2); 311 if (p + 2 > endp) 312 goto trunc; 313 al = (*p << 8) + *(p + 1); 314 printf(", al=%d, a=", al); 315 p += 2; 316 TCHECK2(*p, al); 317 if (p + al > endp) 318 goto trunc; 319 while (al-- > 0) 320 printf(" %02x", *p++); 321 } 322 num--; 323 if (num) 324 printf(" "); 325 } 326 327 return 0; 328 329 trunc: 330 return -1; 331 } 332 333 334 static int 335 cdp_print_prefixes(const u_char * p, int l) 336 { 337 if (l % 5) 338 goto trunc; 339 340 printf(" IPv4 Prefixes (%d):", l / 5); 341 342 while (l > 0) { 343 printf(" %u.%u.%u.%u/%u", p[0], p[1], p[2], p[3], p[4]); 344 l -= 5; 345 p += 5; 346 } 347 348 return 0; 349 350 trunc: 351 return -1; 352 } 353 354 /* read in a <n>-byte number, MSB first 355 * (of course this can handle max sizeof(long)) 356 */ 357 static unsigned long cdp_get_number(const u_char * p, int l) 358 { 359 unsigned long res=0; 360 while( l>0 ) 361 { 362 res = (res<<8) + *p; 363 p++; l--; 364 } 365 return res; 366 } 367