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