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 #include <sys/cdefs.h> 28 #ifndef lint 29 #if 0 30 static const char rcsid[] _U_ = 31 "@(#) Header: /tcpdump/master/tcpdump/print-cdp.c,v 1.25 2004-10-07 14:53:11 hannes Exp "; 32 #else 33 __RCSID("$NetBSD: print-cdp.c,v 1.4 2013/12/31 17:33:31 christos Exp $"); 34 #endif 35 #endif 36 37 #ifdef HAVE_CONFIG_H 38 #include "config.h" 39 #endif 40 41 #include <tcpdump-stdinc.h> 42 43 #include <stdio.h> 44 #include <string.h> 45 46 #include "interface.h" 47 #include "addrtoname.h" 48 #include "extract.h" /* must come after interface.h */ 49 #include "nlpid.h" 50 51 #define CDP_HEADER_LEN 4 52 53 static const struct tok cdp_tlv_values[] = { 54 { 0x01, "Device-ID"}, 55 { 0x02, "Address"}, 56 { 0x03, "Port-ID"}, 57 { 0x04, "Capability"}, 58 { 0x05, "Version String"}, 59 { 0x06, "Platform"}, 60 { 0x07, "Prefixes"}, 61 { 0x08, "Protocol-Hello option"}, 62 { 0x09, "VTP Management Domain"}, 63 { 0x0a, "Native VLAN ID"}, 64 { 0x0b, "Duplex"}, 65 { 0x0e, "ATA-186 VoIP VLAN request"}, 66 { 0x0f, "ATA-186 VoIP VLAN assignment"}, 67 { 0x10, "power consumption"}, 68 { 0x11, "MTU"}, 69 { 0x12, "AVVID trust bitmap"}, 70 { 0x13, "AVVID untrusted ports CoS"}, 71 { 0x14, "System Name"}, 72 { 0x15, "System Object ID (not decoded)"}, 73 { 0x16, "Management Addresses"}, 74 { 0x17, "Physical Location"}, 75 { 0, NULL} 76 }; 77 78 static const struct tok cdp_capability_values[] = { 79 { 0x01, "Router" }, 80 { 0x02, "Transparent Bridge" }, 81 { 0x04, "Source Route Bridge" }, 82 { 0x08, "L2 Switch" }, 83 { 0x10, "L3 capable" }, 84 { 0x20, "IGMP snooping" }, 85 { 0x40, "L1 capable" }, 86 { 0, NULL } 87 }; 88 89 static int cdp_print_addr(const u_char *, int); 90 static int cdp_print_prefixes(const u_char *, int); 91 static unsigned long cdp_get_number(const u_char *, int); 92 93 void 94 cdp_print(const u_char *pptr, u_int length, u_int caplen) 95 { 96 int type, len, i, j; 97 const u_char *tptr; 98 99 if (caplen < CDP_HEADER_LEN) { 100 (void)printf("[|cdp]"); 101 return; 102 } 103 104 tptr = pptr; /* temporary pointer */ 105 106 if (!TTEST2(*tptr, CDP_HEADER_LEN)) 107 goto trunc; 108 printf("CDPv%u, ttl: %us", *tptr, *(tptr+1)); 109 if (vflag) 110 printf(", checksum: %u (unverified), length %u", EXTRACT_16BITS(tptr), length); 111 tptr += CDP_HEADER_LEN; 112 113 while (tptr < (pptr+length)) { 114 115 if (!TTEST2(*tptr, 4)) /* read out Type and Length */ 116 goto trunc; 117 type = EXTRACT_16BITS(tptr); 118 len = EXTRACT_16BITS(tptr+2); /* object length includes the 4 bytes header length */ 119 tptr += 4; 120 len -= 4; 121 122 if (!TTEST2(*tptr, len)) 123 goto trunc; 124 125 if (vflag || type == 1) { /* in non-verbose mode just print Device-ID */ 126 127 if (vflag) 128 printf("\n\t%s (0x%02x), length: %u byte%s: ", 129 tok2str(cdp_tlv_values,"unknown field type", type), 130 type, 131 len, 132 PLURAL_SUFFIX(len)); /* plural */ 133 134 switch (type) { 135 136 case 0x01: /* Device-ID */ 137 if (!vflag) 138 printf(", Device-ID "); 139 printf("'"); 140 fn_printn(tptr, len, NULL); 141 printf("'"); 142 break; 143 case 0x02: /* Address */ 144 if (cdp_print_addr(tptr, len) < 0) 145 goto trunc; 146 break; 147 case 0x03: /* Port-ID */ 148 printf("'"); 149 fn_printn(tptr, len, NULL); 150 printf("'"); 151 break; 152 case 0x04: /* Capabilities */ 153 printf("(0x%08x): %s", 154 EXTRACT_32BITS(tptr), 155 bittok2str(cdp_capability_values, "none",EXTRACT_32BITS(tptr))); 156 break; 157 case 0x05: /* Version */ 158 printf("\n\t "); 159 for (i=0;i<len;i++) { 160 j = *(tptr+i); 161 putchar(j); 162 if (j == 0x0a) /* lets rework the version string to get a nice identation */ 163 printf("\t "); 164 } 165 break; 166 case 0x06: /* Platform */ 167 printf("'"); 168 fn_printn(tptr, len, NULL); 169 printf("'"); 170 break; 171 case 0x07: /* Prefixes */ 172 if (cdp_print_prefixes(tptr, len) < 0) 173 goto trunc; 174 break; 175 case 0x08: /* Protocol Hello Option - not documented */ 176 break; 177 case 0x09: /* VTP Mgmt Domain - not documented */ 178 printf("'"); 179 fn_printn(tptr, len, NULL); 180 printf("'"); 181 break; 182 case 0x0a: /* Native VLAN ID - not documented */ 183 printf("%d",EXTRACT_16BITS(tptr)); 184 break; 185 case 0x0b: /* Duplex - not documented */ 186 printf("%s", *(tptr) ? "full": "half"); 187 break; 188 189 /* http://www.cisco.com/univercd/cc/td/doc/product/voice/ata/atarn/186rn21m.htm 190 * plus more details from other sources 191 */ 192 case 0x0e: /* ATA-186 VoIP VLAN request - incomplete doc. */ 193 printf("app %d, vlan %d", 194 *(tptr), EXTRACT_16BITS(tptr+1)); 195 break; 196 case 0x10: /* ATA-186 VoIP VLAN assignment - incomplete doc. */ 197 printf("%1.2fW", 198 cdp_get_number(tptr, len)/1000.0 ); 199 break; 200 case 0x11: /* MTU - not documented */ 201 printf("%u bytes", EXTRACT_32BITS(tptr)); 202 break; 203 case 0x12: /* AVVID trust bitmap - not documented */ 204 printf("0x%02x", *(tptr) ); 205 break; 206 case 0x13: /* AVVID untrusted port CoS - not documented */ 207 printf("0x%02x", *(tptr)); 208 break; 209 case 0x14: /* System Name - not documented */ 210 printf("'"); 211 fn_printn(tptr, len, NULL); 212 printf("'"); 213 break; 214 case 0x16: /* System Object ID - not documented */ 215 if (cdp_print_addr(tptr, len) < 0) 216 goto trunc; 217 break; 218 case 0x17: /* Physical Location - not documented */ 219 printf("0x%02x", *(tptr)); 220 if (len > 1) { 221 printf("/"); 222 fn_printn(tptr + 1, len - 1, NULL); 223 } 224 break; 225 default: 226 print_unknown_data(tptr,"\n\t ",len); 227 break; 228 } 229 } 230 /* avoid infinite loop */ 231 if (len == 0) 232 break; 233 tptr = tptr+len; 234 } 235 if (vflag < 1) 236 printf(", length %u",caplen); 237 238 return; 239 trunc: 240 printf("[|cdp]"); 241 } 242 243 /* 244 * Protocol type values. 245 * 246 * PT_NLPID means that the protocol type field contains an OSI NLPID. 247 * 248 * PT_IEEE_802_2 means that the protocol type field contains an IEEE 802.2 249 * LLC header that specifies that the payload is for that protocol. 250 */ 251 #define PT_NLPID 1 /* OSI NLPID */ 252 #define PT_IEEE_802_2 2 /* IEEE 802.2 LLC header */ 253 254 static int 255 cdp_print_addr(const u_char * p, int l) 256 { 257 int pt, pl, al, num; 258 const u_char *endp = p + l; 259 #ifdef INET6 260 static u_char prot_ipv6[] = { 261 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00, 0x86, 0xdd 262 }; 263 #endif 264 265 TCHECK2(*p, 2); 266 num = EXTRACT_32BITS(p); 267 p += 4; 268 269 while (p < endp && num >= 0) { 270 TCHECK2(*p, 2); 271 if (p + 2 > endp) 272 goto trunc; 273 pt = p[0]; /* type of "protocol" field */ 274 pl = p[1]; /* length of "protocol" field */ 275 p += 2; 276 277 TCHECK2(p[pl], 2); 278 if (p + pl + 2 > endp) 279 goto trunc; 280 al = EXTRACT_16BITS(&p[pl]); /* address length */ 281 282 if (pt == PT_NLPID && pl == 1 && *p == NLPID_IP && al == 4) { 283 /* 284 * IPv4: protocol type = NLPID, protocol length = 1 285 * (1-byte NLPID), protocol = 0xcc (NLPID for IPv4), 286 * address length = 4 287 */ 288 p += 3; 289 290 TCHECK2(*p, 4); 291 if (p + 4 > endp) 292 goto trunc; 293 printf("IPv4 (%u) %s", 294 num, 295 ipaddr_string(p)); 296 p += 4; 297 } 298 #ifdef INET6 299 else if (pt == PT_IEEE_802_2 && pl == 8 && 300 memcmp(p, prot_ipv6, 8) == 0 && al == 16) { 301 /* 302 * IPv6: protocol type = IEEE 802.2 header, 303 * protocol length = 8 (size of LLC+SNAP header), 304 * protocol = LLC+SNAP header with the IPv6 305 * Ethertype, address length = 16 306 */ 307 p += 10; 308 TCHECK2(*p, al); 309 if (p + al > endp) 310 goto trunc; 311 312 printf("IPv6 (%u) %s", 313 num, 314 ip6addr_string(p)); 315 p += al; 316 } 317 #endif 318 else { 319 /* 320 * Generic case: just print raw data 321 */ 322 TCHECK2(*p, pl); 323 if (p + pl > endp) 324 goto trunc; 325 printf("pt=0x%02x, pl=%d, pb=", *(p - 2), pl); 326 while (pl-- > 0) 327 printf(" %02x", *p++); 328 TCHECK2(*p, 2); 329 if (p + 2 > endp) 330 goto trunc; 331 al = (*p << 8) + *(p + 1); 332 printf(", al=%d, a=", al); 333 p += 2; 334 TCHECK2(*p, al); 335 if (p + al > endp) 336 goto trunc; 337 while (al-- > 0) 338 printf(" %02x", *p++); 339 } 340 num--; 341 if (num) 342 printf(" "); 343 } 344 345 return 0; 346 347 trunc: 348 return -1; 349 } 350 351 352 static int 353 cdp_print_prefixes(const u_char * p, int l) 354 { 355 if (l % 5) 356 goto trunc; 357 358 printf(" IPv4 Prefixes (%d):", l / 5); 359 360 while (l > 0) { 361 printf(" %u.%u.%u.%u/%u", p[0], p[1], p[2], p[3], p[4]); 362 l -= 5; 363 p += 5; 364 } 365 366 return 0; 367 368 trunc: 369 return -1; 370 } 371 372 /* read in a <n>-byte number, MSB first 373 * (of course this can handle max sizeof(long)) 374 */ 375 static unsigned long cdp_get_number(const u_char * p, int l) 376 { 377 unsigned long res=0; 378 while( l>0 ) 379 { 380 res = (res<<8) + *p; 381 p++; l--; 382 } 383 return res; 384 } 385