| /* |
| * Copyright (c) 1998-2007 The TCPDUMP project |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that: (1) source code |
| * distributions retain the above copyright notice and this paragraph |
| * in its entirety, and (2) distributions including binary code include |
| * the above copyright notice and this paragraph in its entirety in |
| * the documentation or other materials provided with the distribution. |
| * THIS SOFTWARE IS PROVIDED ``AS IS'' AND |
| * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT |
| * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS |
| * FOR A PARTICULAR PURPOSE. |
| * |
| * Reference documentation: |
| * https://www.cisco.com/c/en/us/support/docs/lan-switching/vtp/10558-21.html |
| * https://docstore.mik.ua/univercd/cc/td/doc/product/lan/trsrb/frames.htm |
| * |
| * Original code ode by Carles Kishimoto <[email protected]> |
| */ |
| |
| /* \summary: Cisco VLAN Trunking Protocol (VTP) printer */ |
| |
| #ifdef HAVE_CONFIG_H |
| #include <config.h> |
| #endif |
| |
| #include "netdissect-stdinc.h" |
| |
| #define ND_LONGJMP_FROM_TCHECK |
| #include "netdissect.h" |
| #include "addrtoname.h" |
| #include "extract.h" |
| |
| #define VTP_HEADER_LEN 36 |
| #define VTP_DOMAIN_NAME_LEN 32 |
| #define VTP_MD5_DIGEST_LEN 16 |
| #define VTP_UPDATE_TIMESTAMP_LEN 12 |
| #define VTP_VLAN_INFO_FIXED_PART_LEN 12 /* length of VLAN info before VLAN name */ |
| |
| #define VTP_SUMMARY_ADV 0x01 |
| #define VTP_SUBSET_ADV 0x02 |
| #define VTP_ADV_REQUEST 0x03 |
| #define VTP_JOIN_MESSAGE 0x04 |
| |
| struct vtp_vlan_ { |
| nd_uint8_t len; |
| nd_uint8_t status; |
| nd_uint8_t type; |
| nd_uint8_t name_len; |
| nd_uint16_t vlanid; |
| nd_uint16_t mtu; |
| nd_uint32_t index; |
| }; |
| |
| static const struct tok vtp_message_type_values[] = { |
| { VTP_SUMMARY_ADV, "Summary advertisement"}, |
| { VTP_SUBSET_ADV, "Subset advertisement"}, |
| { VTP_ADV_REQUEST, "Advertisement request"}, |
| { VTP_JOIN_MESSAGE, "Join message"}, |
| { 0, NULL } |
| }; |
| |
| static const struct tok vtp_header_values[] = { |
| { 0x01, "Followers"}, /* On Summary advertisement, 3rd byte is Followers */ |
| { 0x02, "Seq number"}, /* On Subset advertisement, 3rd byte is Sequence number */ |
| { 0x03, "Rsvd"}, /* On Adver. requests 3rd byte is Rsvd */ |
| { 0x04, "Rsvd"}, /* On Adver. requests 3rd byte is Rsvd */ |
| { 0, NULL } |
| }; |
| |
| static const struct tok vtp_vlan_type_values[] = { |
| { 0x01, "Ethernet"}, |
| { 0x02, "FDDI"}, |
| { 0x03, "TrCRF"}, |
| { 0x04, "FDDI-net"}, |
| { 0x05, "TrBRF"}, |
| { 0, NULL } |
| }; |
| |
| static const struct tok vtp_vlan_status[] = { |
| { 0x00, "Operational"}, |
| { 0x01, "Suspended"}, |
| { 0, NULL } |
| }; |
| |
| #define VTP_VLAN_SOURCE_ROUTING_RING_NUMBER 0x01 |
| #define VTP_VLAN_SOURCE_ROUTING_BRIDGE_NUMBER 0x02 |
| #define VTP_VLAN_STP_TYPE 0x03 |
| #define VTP_VLAN_PARENT_VLAN 0x04 |
| #define VTP_VLAN_TRANS_BRIDGED_VLAN 0x05 |
| #define VTP_VLAN_PRUNING 0x06 |
| #define VTP_VLAN_BRIDGE_TYPE 0x07 |
| #define VTP_VLAN_ARP_HOP_COUNT 0x08 |
| #define VTP_VLAN_STE_HOP_COUNT 0x09 |
| #define VTP_VLAN_BACKUP_CRF_MODE 0x0A |
| |
| static const struct tok vtp_vlan_tlv_values[] = { |
| { VTP_VLAN_SOURCE_ROUTING_RING_NUMBER, "Source-Routing Ring Number TLV"}, |
| { VTP_VLAN_SOURCE_ROUTING_BRIDGE_NUMBER, "Source-Routing Bridge Number TLV"}, |
| { VTP_VLAN_STP_TYPE, "STP type TLV"}, |
| { VTP_VLAN_PARENT_VLAN, "Parent VLAN TLV"}, |
| { VTP_VLAN_TRANS_BRIDGED_VLAN, "Translationally bridged VLANs TLV"}, |
| { VTP_VLAN_PRUNING, "Pruning TLV"}, |
| { VTP_VLAN_BRIDGE_TYPE, "Bridge Type TLV"}, |
| { VTP_VLAN_ARP_HOP_COUNT, "Max ARP Hop Count TLV"}, |
| { VTP_VLAN_STE_HOP_COUNT, "Max STE Hop Count TLV"}, |
| { VTP_VLAN_BACKUP_CRF_MODE, "Backup CRF Mode TLV"}, |
| { 0, NULL } |
| }; |
| |
| static const struct tok vtp_stp_type_values[] = { |
| { 1, "SRT"}, |
| { 2, "SRB"}, |
| { 3, "Auto"}, |
| { 0, NULL } |
| }; |
| |
| void |
| vtp_print(netdissect_options *ndo, |
| const u_char *pptr, const u_int length) |
| { |
| u_int type, len, name_len, tlv_len, tlv_value, mgmtd_len; |
| const u_char *tptr; |
| const struct vtp_vlan_ *vtp_vlan; |
| |
| ndo->ndo_protocol = "vtp"; |
| if (length < VTP_HEADER_LEN) |
| goto invalid; |
| |
| tptr = pptr; |
| |
| ND_TCHECK_LEN(tptr, VTP_HEADER_LEN); |
| |
| type = GET_U_1(tptr + 1); |
| ND_PRINT("VTPv%u, Message %s (0x%02x), length %u", |
| GET_U_1(tptr), |
| tok2str(vtp_message_type_values,"Unknown message type", type), |
| type, |
| length); |
| |
| /* In non-verbose mode, just print version and message type */ |
| if (ndo->ndo_vflag < 1) { |
| goto tcheck_full_packet; |
| } |
| |
| /* verbose mode print all fields */ |
| ND_PRINT("\n\tDomain name: "); |
| mgmtd_len = GET_U_1(tptr + 3); |
| if (mgmtd_len < 1 || mgmtd_len > VTP_DOMAIN_NAME_LEN) { |
| ND_PRINT(" [invalid MgmtD Len %u]", mgmtd_len); |
| goto invalid; |
| } |
| nd_printjnp(ndo, tptr + 4, mgmtd_len); |
| ND_PRINT(", %s: %u", |
| tok2str(vtp_header_values, "Unknown", type), |
| GET_U_1(tptr + 2)); |
| |
| tptr += VTP_HEADER_LEN; |
| |
| switch (type) { |
| |
| case VTP_SUMMARY_ADV: |
| |
| /* |
| * SUMMARY ADVERTISEMENT |
| * |
| * 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 |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | Version | Code | Followers | MgmtD Len | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | Management Domain Name (zero-padded to 32 bytes) | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | Configuration revision number | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | Updater Identity IP address | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | Update Timestamp (12 bytes) | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | MD5 digest (16 bytes) | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * |
| */ |
| |
| ND_PRINT("\n\t Config Rev %x, Updater %s", |
| GET_BE_U_4(tptr), |
| GET_IPADDR_STRING(tptr+4)); |
| tptr += 8; |
| ND_PRINT(", Timestamp 0x%08x 0x%08x 0x%08x", |
| GET_BE_U_4(tptr), |
| GET_BE_U_4(tptr + 4), |
| GET_BE_U_4(tptr + 8)); |
| tptr += VTP_UPDATE_TIMESTAMP_LEN; |
| ND_PRINT(", MD5 digest: %08x%08x%08x%08x", |
| GET_BE_U_4(tptr), |
| GET_BE_U_4(tptr + 4), |
| GET_BE_U_4(tptr + 8), |
| GET_BE_U_4(tptr + 12)); |
| tptr += VTP_MD5_DIGEST_LEN; |
| break; |
| |
| case VTP_SUBSET_ADV: |
| |
| /* |
| * SUBSET ADVERTISEMENT |
| * |
| * 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 |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | Version | Code | Seq number | MgmtD Len | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | Management Domain Name (zero-padded to 32 bytes) | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | Configuration revision number | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | VLAN info field 1 | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | ................ | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | VLAN info field N | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * |
| */ |
| |
| ND_PRINT(", Config Rev %x", GET_BE_U_4(tptr)); |
| |
| /* |
| * VLAN INFORMATION |
| * 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 |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | V info len | Status | VLAN type | VLAN name len | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | ISL vlan id | MTU size | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | 802.10 index (SAID) | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | VLAN name | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * |
| */ |
| |
| tptr += 4; |
| while ((unsigned)(tptr - pptr) < length) { |
| |
| len = GET_U_1(tptr); |
| if (len == 0) |
| break; |
| |
| ND_TCHECK_LEN(tptr, len); |
| |
| vtp_vlan = (const struct vtp_vlan_*)tptr; |
| if (len < VTP_VLAN_INFO_FIXED_PART_LEN) |
| goto invalid; |
| ND_PRINT("\n\tVLAN info status %s, type %s, VLAN-id %u, MTU %u, SAID 0x%08x, Name ", |
| tok2str(vtp_vlan_status,"Unknown",GET_U_1(vtp_vlan->status)), |
| tok2str(vtp_vlan_type_values,"Unknown",GET_U_1(vtp_vlan->type)), |
| GET_BE_U_2(vtp_vlan->vlanid), |
| GET_BE_U_2(vtp_vlan->mtu), |
| GET_BE_U_4(vtp_vlan->index)); |
| len -= VTP_VLAN_INFO_FIXED_PART_LEN; |
| tptr += VTP_VLAN_INFO_FIXED_PART_LEN; |
| name_len = GET_U_1(vtp_vlan->name_len); |
| if (len < 4*((name_len + 3)/4)) |
| goto invalid; |
| nd_printjnp(ndo, tptr, name_len); |
| |
| /* |
| * Vlan names are aligned to 32-bit boundaries. |
| */ |
| len -= 4*((name_len + 3)/4); |
| tptr += 4*((name_len + 3)/4); |
| |
| /* TLV information follows */ |
| |
| while (len > 0) { |
| |
| /* |
| * Cisco specs say 2 bytes for type + 2 bytes for length; |
| * see https://docstore.mik.ua/univercd/cc/td/doc/product/lan/trsrb/frames.htm |
| * However, actual packets on the wire appear to use 1 |
| * byte for the type and 1 byte for the length, so that's |
| * what we do. |
| */ |
| if (len < 2) |
| goto invalid; |
| type = GET_U_1(tptr); |
| tlv_len = GET_U_1(tptr + 1); |
| |
| ND_PRINT("\n\t\t%s (0x%04x) TLV", |
| tok2str(vtp_vlan_tlv_values, "Unknown", type), |
| type); |
| |
| if (len < tlv_len * 2 + 2) { |
| ND_PRINT(" (TLV goes past the end of the packet)"); |
| goto invalid; |
| } |
| ND_TCHECK_LEN(tptr, tlv_len * 2 + 2); |
| |
| /* |
| * We assume the value is a 2-byte integer; the length is |
| * in units of 16-bit words. |
| */ |
| if (tlv_len != 1) { |
| ND_PRINT(" (invalid TLV length %u != 1)", tlv_len); |
| goto invalid; |
| } else { |
| tlv_value = GET_BE_U_2(tptr + 2); |
| |
| switch (type) { |
| case VTP_VLAN_STE_HOP_COUNT: |
| ND_PRINT(", %u", tlv_value); |
| break; |
| |
| case VTP_VLAN_PRUNING: |
| ND_PRINT(", %s (%u)", |
| tlv_value == 1 ? "Enabled" : "Disabled", |
| tlv_value); |
| break; |
| |
| case VTP_VLAN_STP_TYPE: |
| ND_PRINT(", %s (%u)", |
| tok2str(vtp_stp_type_values, "Unknown", tlv_value), |
| tlv_value); |
| break; |
| |
| case VTP_VLAN_BRIDGE_TYPE: |
| ND_PRINT(", %s (%u)", |
| tlv_value == 1 ? "SRB" : "SRT", |
| tlv_value); |
| break; |
| |
| case VTP_VLAN_BACKUP_CRF_MODE: |
| ND_PRINT(", %s (%u)", |
| tlv_value == 1 ? "Backup" : "Not backup", |
| tlv_value); |
| break; |
| |
| /* |
| * FIXME those are the defined TLVs that lack a decoder |
| * you are welcome to contribute code ;-) |
| */ |
| |
| case VTP_VLAN_SOURCE_ROUTING_RING_NUMBER: |
| case VTP_VLAN_SOURCE_ROUTING_BRIDGE_NUMBER: |
| case VTP_VLAN_PARENT_VLAN: |
| case VTP_VLAN_TRANS_BRIDGED_VLAN: |
| case VTP_VLAN_ARP_HOP_COUNT: |
| default: |
| print_unknown_data(ndo, tptr, "\n\t\t ", 2 + tlv_len*2); |
| break; |
| } |
| } |
| len -= 2 + tlv_len*2; |
| tptr += 2 + tlv_len*2; |
| } |
| } |
| break; |
| |
| case VTP_ADV_REQUEST: |
| |
| /* |
| * ADVERTISEMENT REQUEST |
| * |
| * 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 |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | Version | Code | Reserved | MgmtD Len | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | Management Domain Name (zero-padded to 32 bytes) | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | Start value | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * |
| */ |
| |
| ND_PRINT("\n\tStart value: %u", GET_BE_U_4(tptr)); |
| break; |
| |
| case VTP_JOIN_MESSAGE: |
| |
| /* FIXME - Could not find message format */ |
| break; |
| |
| default: |
| break; |
| } |
| |
| return; |
| |
| invalid: |
| nd_print_invalid(ndo); |
| tcheck_full_packet: |
| ND_TCHECK_LEN(pptr, length); |
| } |
