1 /* 2 * Copyright (c) 1998-2007 The TCPDUMP project 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that: (1) source code 6 * distributions retain the above copyright notice and this paragraph 7 * in its entirety, and (2) distributions including binary code include 8 * the above copyright notice and this paragraph in its entirety in 9 * the documentation or other materials provided with the distribution. 10 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND 11 * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT 12 * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 13 * FOR A PARTICULAR PURPOSE. 14 * 15 * Reference documentation: 16 * http://www.cisco.com/en/US/tech/tk389/tk689/technologies_tech_note09186a0080094c52.shtml 17 * http://www.cisco.com/warp/public/473/21.html 18 * http://www.cisco.com/univercd/cc/td/doc/product/lan/trsrb/frames.htm 19 * 20 * Original code ode by Carles Kishimoto <carles.kishimoto@gmail.com> 21 */ 22 23 /* \summary: Cisco VLAN Trunking Protocol (VTP) printer */ 24 25 #ifdef HAVE_CONFIG_H 26 #include "config.h" 27 #endif 28 29 #include <netdissect-stdinc.h> 30 31 #include "netdissect.h" 32 #include "addrtoname.h" 33 #include "extract.h" 34 35 #define VTP_HEADER_LEN 36 36 #define VTP_DOMAIN_NAME_LEN 32 37 #define VTP_MD5_DIGEST_LEN 16 38 #define VTP_UPDATE_TIMESTAMP_LEN 12 39 #define VTP_VLAN_INFO_OFFSET 12 40 41 #define VTP_SUMMARY_ADV 0x01 42 #define VTP_SUBSET_ADV 0x02 43 #define VTP_ADV_REQUEST 0x03 44 #define VTP_JOIN_MESSAGE 0x04 45 46 struct vtp_vlan_ { 47 uint8_t len; 48 uint8_t status; 49 uint8_t type; 50 uint8_t name_len; 51 uint16_t vlanid; 52 uint16_t mtu; 53 uint32_t index; 54 }; 55 56 static const struct tok vtp_message_type_values[] = { 57 { VTP_SUMMARY_ADV, "Summary advertisement"}, 58 { VTP_SUBSET_ADV, "Subset advertisement"}, 59 { VTP_ADV_REQUEST, "Advertisement request"}, 60 { VTP_JOIN_MESSAGE, "Join message"}, 61 { 0, NULL } 62 }; 63 64 static const struct tok vtp_header_values[] = { 65 { 0x01, "Followers"}, /* On Summary advertisement, 3rd byte is Followers */ 66 { 0x02, "Seq number"}, /* On Subset advertisement, 3rd byte is Sequence number */ 67 { 0x03, "Rsvd"}, /* On Adver. requests 3rd byte is Rsvd */ 68 { 0x04, "Rsvd"}, /* On Adver. requests 3rd byte is Rsvd */ 69 { 0, NULL } 70 }; 71 72 static const struct tok vtp_vlan_type_values[] = { 73 { 0x01, "Ethernet"}, 74 { 0x02, "FDDI"}, 75 { 0x03, "TrCRF"}, 76 { 0x04, "FDDI-net"}, 77 { 0x05, "TrBRF"}, 78 { 0, NULL } 79 }; 80 81 static const struct tok vtp_vlan_status[] = { 82 { 0x00, "Operational"}, 83 { 0x01, "Suspended"}, 84 { 0, NULL } 85 }; 86 87 #define VTP_VLAN_SOURCE_ROUTING_RING_NUMBER 0x01 88 #define VTP_VLAN_SOURCE_ROUTING_BRIDGE_NUMBER 0x02 89 #define VTP_VLAN_STP_TYPE 0x03 90 #define VTP_VLAN_PARENT_VLAN 0x04 91 #define VTP_VLAN_TRANS_BRIDGED_VLAN 0x05 92 #define VTP_VLAN_PRUNING 0x06 93 #define VTP_VLAN_BRIDGE_TYPE 0x07 94 #define VTP_VLAN_ARP_HOP_COUNT 0x08 95 #define VTP_VLAN_STE_HOP_COUNT 0x09 96 #define VTP_VLAN_BACKUP_CRF_MODE 0x0A 97 98 static const struct tok vtp_vlan_tlv_values[] = { 99 { VTP_VLAN_SOURCE_ROUTING_RING_NUMBER, "Source-Routing Ring Number TLV"}, 100 { VTP_VLAN_SOURCE_ROUTING_BRIDGE_NUMBER, "Source-Routing Bridge Number TLV"}, 101 { VTP_VLAN_STP_TYPE, "STP type TLV"}, 102 { VTP_VLAN_PARENT_VLAN, "Parent VLAN TLV"}, 103 { VTP_VLAN_TRANS_BRIDGED_VLAN, "Translationally bridged VLANs TLV"}, 104 { VTP_VLAN_PRUNING, "Pruning TLV"}, 105 { VTP_VLAN_BRIDGE_TYPE, "Bridge Type TLV"}, 106 { VTP_VLAN_ARP_HOP_COUNT, "Max ARP Hop Count TLV"}, 107 { VTP_VLAN_STE_HOP_COUNT, "Max STE Hop Count TLV"}, 108 { VTP_VLAN_BACKUP_CRF_MODE, "Backup CRF Mode TLV"}, 109 { 0, NULL } 110 }; 111 112 static const struct tok vtp_stp_type_values[] = { 113 { 1, "SRT"}, 114 { 2, "SRB"}, 115 { 3, "Auto"}, 116 { 0, NULL } 117 }; 118 119 void 120 vtp_print (netdissect_options *ndo, 121 const u_char *pptr, u_int length) 122 { 123 int type, len, tlv_len, tlv_value, mgmtd_len; 124 const u_char *tptr; 125 const struct vtp_vlan_ *vtp_vlan; 126 127 if (length < VTP_HEADER_LEN) 128 goto trunc; 129 130 tptr = pptr; 131 132 ND_TCHECK2(*tptr, VTP_HEADER_LEN); 133 134 type = *(tptr+1); 135 ND_PRINT((ndo, "VTPv%u, Message %s (0x%02x), length %u", 136 *tptr, 137 tok2str(vtp_message_type_values,"Unknown message type", type), 138 type, 139 length)); 140 141 /* In non-verbose mode, just print version and message type */ 142 if (ndo->ndo_vflag < 1) { 143 return; 144 } 145 146 /* verbose mode print all fields */ 147 ND_PRINT((ndo, "\n\tDomain name: ")); 148 mgmtd_len = *(tptr + 3); 149 if (mgmtd_len < 1 || mgmtd_len > 32) { 150 ND_PRINT((ndo, " [invalid MgmtD Len %d]", mgmtd_len)); 151 return; 152 } 153 fn_printzp(ndo, tptr + 4, mgmtd_len, NULL); 154 ND_PRINT((ndo, ", %s: %u", 155 tok2str(vtp_header_values, "Unknown", type), 156 *(tptr+2))); 157 158 tptr += VTP_HEADER_LEN; 159 160 switch (type) { 161 162 case VTP_SUMMARY_ADV: 163 164 /* 165 * SUMMARY ADVERTISEMENT 166 * 167 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 168 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 169 * | Version | Code | Followers | MgmtD Len | 170 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 171 * | Management Domain Name (zero-padded to 32 bytes) | 172 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 173 * | Configuration revision number | 174 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 175 * | Updater Identity IP address | 176 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 177 * | Update Timestamp (12 bytes) | 178 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 179 * | MD5 digest (16 bytes) | 180 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 181 * 182 */ 183 184 ND_TCHECK2(*tptr, 8); 185 ND_PRINT((ndo, "\n\t Config Rev %x, Updater %s", 186 EXTRACT_32BITS(tptr), 187 ipaddr_string(ndo, tptr+4))); 188 tptr += 8; 189 ND_TCHECK2(*tptr, VTP_UPDATE_TIMESTAMP_LEN); 190 ND_PRINT((ndo, ", Timestamp 0x%08x 0x%08x 0x%08x", 191 EXTRACT_32BITS(tptr), 192 EXTRACT_32BITS(tptr + 4), 193 EXTRACT_32BITS(tptr + 8))); 194 tptr += VTP_UPDATE_TIMESTAMP_LEN; 195 ND_TCHECK2(*tptr, VTP_MD5_DIGEST_LEN); 196 ND_PRINT((ndo, ", MD5 digest: %08x%08x%08x%08x", 197 EXTRACT_32BITS(tptr), 198 EXTRACT_32BITS(tptr + 4), 199 EXTRACT_32BITS(tptr + 8), 200 EXTRACT_32BITS(tptr + 12))); 201 tptr += VTP_MD5_DIGEST_LEN; 202 break; 203 204 case VTP_SUBSET_ADV: 205 206 /* 207 * SUBSET ADVERTISEMENT 208 * 209 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 210 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 211 * | Version | Code | Seq number | MgmtD Len | 212 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 213 * | Management Domain Name (zero-padded to 32 bytes) | 214 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 215 * | Configuration revision number | 216 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 217 * | VLAN info field 1 | 218 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 219 * | ................ | 220 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 221 * | VLAN info field N | 222 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 223 * 224 */ 225 226 ND_PRINT((ndo, ", Config Rev %x", EXTRACT_32BITS(tptr))); 227 228 /* 229 * VLAN INFORMATION 230 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 231 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 232 * | V info len | Status | VLAN type | VLAN name len | 233 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 234 * | ISL vlan id | MTU size | 235 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 236 * | 802.10 index (SAID) | 237 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 238 * | VLAN name | 239 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 240 * 241 */ 242 243 tptr += 4; 244 while (tptr < (pptr+length)) { 245 246 len = *tptr; 247 if (len == 0) 248 break; 249 250 ND_TCHECK2(*tptr, len); 251 252 vtp_vlan = (const struct vtp_vlan_*)tptr; 253 ND_TCHECK(*vtp_vlan); 254 ND_PRINT((ndo, "\n\tVLAN info status %s, type %s, VLAN-id %u, MTU %u, SAID 0x%08x, Name ", 255 tok2str(vtp_vlan_status,"Unknown",vtp_vlan->status), 256 tok2str(vtp_vlan_type_values,"Unknown",vtp_vlan->type), 257 EXTRACT_16BITS(&vtp_vlan->vlanid), 258 EXTRACT_16BITS(&vtp_vlan->mtu), 259 EXTRACT_32BITS(&vtp_vlan->index))); 260 fn_printzp(ndo, tptr + VTP_VLAN_INFO_OFFSET, vtp_vlan->name_len, NULL); 261 262 /* 263 * Vlan names are aligned to 32-bit boundaries. 264 */ 265 len -= VTP_VLAN_INFO_OFFSET + 4*((vtp_vlan->name_len + 3)/4); 266 tptr += VTP_VLAN_INFO_OFFSET + 4*((vtp_vlan->name_len + 3)/4); 267 268 /* TLV information follows */ 269 270 while (len > 0) { 271 272 /* 273 * Cisco specs says 2 bytes for type + 2 bytes for length, take only 1 274 * See: http://www.cisco.com/univercd/cc/td/doc/product/lan/trsrb/frames.htm 275 */ 276 type = *tptr; 277 tlv_len = *(tptr+1); 278 279 ND_PRINT((ndo, "\n\t\t%s (0x%04x) TLV", 280 tok2str(vtp_vlan_tlv_values, "Unknown", type), 281 type)); 282 283 /* 284 * infinite loop check 285 */ 286 if (type == 0 || tlv_len == 0) { 287 return; 288 } 289 290 ND_TCHECK2(*tptr, tlv_len * 2 +2); 291 292 tlv_value = EXTRACT_16BITS(tptr+2); 293 294 switch (type) { 295 case VTP_VLAN_STE_HOP_COUNT: 296 ND_PRINT((ndo, ", %u", tlv_value)); 297 break; 298 299 case VTP_VLAN_PRUNING: 300 ND_PRINT((ndo, ", %s (%u)", 301 tlv_value == 1 ? "Enabled" : "Disabled", 302 tlv_value)); 303 break; 304 305 case VTP_VLAN_STP_TYPE: 306 ND_PRINT((ndo, ", %s (%u)", 307 tok2str(vtp_stp_type_values, "Unknown", tlv_value), 308 tlv_value)); 309 break; 310 311 case VTP_VLAN_BRIDGE_TYPE: 312 ND_PRINT((ndo, ", %s (%u)", 313 tlv_value == 1 ? "SRB" : "SRT", 314 tlv_value)); 315 break; 316 317 case VTP_VLAN_BACKUP_CRF_MODE: 318 ND_PRINT((ndo, ", %s (%u)", 319 tlv_value == 1 ? "Backup" : "Not backup", 320 tlv_value)); 321 break; 322 323 /* 324 * FIXME those are the defined TLVs that lack a decoder 325 * you are welcome to contribute code ;-) 326 */ 327 328 case VTP_VLAN_SOURCE_ROUTING_RING_NUMBER: 329 case VTP_VLAN_SOURCE_ROUTING_BRIDGE_NUMBER: 330 case VTP_VLAN_PARENT_VLAN: 331 case VTP_VLAN_TRANS_BRIDGED_VLAN: 332 case VTP_VLAN_ARP_HOP_COUNT: 333 default: 334 print_unknown_data(ndo, tptr, "\n\t\t ", 2 + tlv_len*2); 335 break; 336 } 337 len -= 2 + tlv_len*2; 338 tptr += 2 + tlv_len*2; 339 } 340 } 341 break; 342 343 case VTP_ADV_REQUEST: 344 345 /* 346 * ADVERTISEMENT REQUEST 347 * 348 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 349 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 350 * | Version | Code | Reserved | MgmtD Len | 351 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 352 * | Management Domain Name (zero-padded to 32 bytes) | 353 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 354 * | Start value | 355 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 356 * 357 */ 358 359 ND_TCHECK2(*tptr, 4); 360 ND_PRINT((ndo, "\n\tStart value: %u", EXTRACT_32BITS(tptr))); 361 break; 362 363 case VTP_JOIN_MESSAGE: 364 365 /* FIXME - Could not find message format */ 366 break; 367 368 default: 369 break; 370 } 371 372 return; 373 374 trunc: 375 ND_PRINT((ndo, "[|vtp]")); 376 } 377 378 /* 379 * Local Variables: 380 * c-style: whitesmith 381 * c-basic-offset: 4 382 * End: 383 */ 384