1 /* 2 * Copyright (c) 1998-2006 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 * Original code by Carles Kishimoto <Carles.Kishimoto@bsc.es> 16 */ 17 18 /* \summary: Cisco VLAN Query Protocol (VQP) printer */ 19 20 #include <config.h> 21 22 #include "netdissect-stdinc.h" 23 24 #define ND_LONGJMP_FROM_TCHECK 25 #include "netdissect.h" 26 #include "extract.h" 27 #include "addrtoname.h" 28 29 #define VQP_VERSION 1 30 31 /* 32 * VQP common header 33 * 34 * 0 1 2 3 35 * 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 36 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 37 * | Constant | Packet type | Error Code | nitems | 38 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 39 * | Packet Sequence Number (4 bytes) | 40 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 41 */ 42 43 struct vqp_common_header_t { 44 nd_uint8_t version; 45 nd_uint8_t msg_type; 46 nd_uint8_t error_code; 47 nd_uint8_t nitems; 48 nd_uint32_t sequence; 49 }; 50 51 struct vqp_obj_tlv_t { 52 nd_uint32_t obj_type; 53 nd_uint16_t obj_length; 54 }; 55 56 #define VQP_OBJ_REQ_JOIN_PORT 0x01 57 #define VQP_OBJ_RESP_VLAN 0x02 58 #define VQP_OBJ_REQ_RECONFIRM 0x03 59 #define VQP_OBJ_RESP_RECONFIRM 0x04 60 61 static const struct tok vqp_msg_type_values[] = { 62 { VQP_OBJ_REQ_JOIN_PORT, "Request, Join Port"}, 63 { VQP_OBJ_RESP_VLAN, "Response, VLAN"}, 64 { VQP_OBJ_REQ_RECONFIRM, "Request, Reconfirm"}, 65 { VQP_OBJ_RESP_RECONFIRM, "Response, Reconfirm"}, 66 { 0, NULL} 67 }; 68 69 static const struct tok vqp_error_code_values[] = { 70 { 0x00, "No error"}, 71 { 0x03, "Access denied"}, 72 { 0x04, "Shutdown port"}, 73 { 0x05, "Wrong VTP domain"}, 74 { 0, NULL} 75 }; 76 77 /* FIXME the heading 0x0c looks ugly - those must be flags etc. */ 78 #define VQP_OBJ_IP_ADDRESS 0x0c01 79 #define VQP_OBJ_PORT_NAME 0x0c02 80 #define VQP_OBJ_VLAN_NAME 0x0c03 81 #define VQP_OBJ_VTP_DOMAIN 0x0c04 82 #define VQP_OBJ_ETHERNET_PKT 0x0c05 83 #define VQP_OBJ_MAC_NULL 0x0c06 84 #define VQP_OBJ_MAC_ADDRESS 0x0c08 85 86 static const struct tok vqp_obj_values[] = { 87 { VQP_OBJ_IP_ADDRESS, "Client IP Address" }, 88 { VQP_OBJ_PORT_NAME, "Port Name" }, 89 { VQP_OBJ_VLAN_NAME, "VLAN Name" }, 90 { VQP_OBJ_VTP_DOMAIN, "VTP Domain" }, 91 { VQP_OBJ_ETHERNET_PKT, "Ethernet Packet" }, 92 { VQP_OBJ_MAC_NULL, "MAC Null" }, 93 { VQP_OBJ_MAC_ADDRESS, "MAC Address" }, 94 { 0, NULL} 95 }; 96 97 void 98 vqp_print(netdissect_options *ndo, const u_char *pptr, u_int len) 99 { 100 const struct vqp_common_header_t *vqp_common_header; 101 const struct vqp_obj_tlv_t *vqp_obj_tlv; 102 103 const u_char *tptr; 104 uint8_t version; 105 uint16_t vqp_obj_len; 106 uint32_t vqp_obj_type; 107 u_int tlen; 108 uint8_t nitems; 109 110 ndo->ndo_protocol = "vqp"; 111 tptr=pptr; 112 tlen = len; 113 vqp_common_header = (const struct vqp_common_header_t *)pptr; 114 ND_TCHECK_SIZE(vqp_common_header); 115 if (sizeof(struct vqp_common_header_t) > tlen) 116 goto invalid; 117 version = GET_U_1(vqp_common_header->version); 118 119 /* 120 * Sanity checking of the header. 121 */ 122 if (version != VQP_VERSION) { 123 ND_PRINT("VQP version %u packet not supported", 124 version); 125 return; 126 } 127 128 /* in non-verbose mode just lets print the basic Message Type */ 129 if (ndo->ndo_vflag < 1) { 130 ND_PRINT("VQPv%u %s Message, error-code %s (%u), length %u", 131 version, 132 tok2str(vqp_msg_type_values, "unknown (%u)",GET_U_1(vqp_common_header->msg_type)), 133 tok2str(vqp_error_code_values, "unknown", GET_U_1(vqp_common_header->error_code)), 134 GET_U_1(vqp_common_header->error_code), 135 len); 136 return; 137 } 138 139 /* ok they seem to want to know everything - lets fully decode it */ 140 nitems = GET_U_1(vqp_common_header->nitems); 141 ND_PRINT("\n\tVQPv%u, %s Message, error-code %s (%u), seq 0x%08x, items %u, length %u", 142 version, 143 tok2str(vqp_msg_type_values, "unknown (%u)",GET_U_1(vqp_common_header->msg_type)), 144 tok2str(vqp_error_code_values, "unknown", GET_U_1(vqp_common_header->error_code)), 145 GET_U_1(vqp_common_header->error_code), 146 GET_BE_U_4(vqp_common_header->sequence), 147 nitems, 148 len); 149 150 /* skip VQP Common header */ 151 tptr+=sizeof(struct vqp_common_header_t); 152 tlen-=sizeof(struct vqp_common_header_t); 153 154 while (nitems != 0 && tlen != 0) { 155 156 vqp_obj_tlv = (const struct vqp_obj_tlv_t *)tptr; 157 ND_TCHECK_SIZE(vqp_obj_tlv); 158 if (sizeof(struct vqp_obj_tlv_t) > tlen) 159 goto invalid; 160 vqp_obj_type = GET_BE_U_4(vqp_obj_tlv->obj_type); 161 vqp_obj_len = GET_BE_U_2(vqp_obj_tlv->obj_length); 162 tptr+=sizeof(struct vqp_obj_tlv_t); 163 tlen-=sizeof(struct vqp_obj_tlv_t); 164 165 ND_PRINT("\n\t %s Object (0x%08x), length %u, value: ", 166 tok2str(vqp_obj_values, "Unknown", vqp_obj_type), 167 vqp_obj_type, vqp_obj_len); 168 169 /* basic sanity check */ 170 if (vqp_obj_type == 0 || vqp_obj_len ==0) { 171 return; 172 } 173 174 /* did we capture enough for fully decoding the object ? */ 175 ND_TCHECK_LEN(tptr, vqp_obj_len); 176 if (vqp_obj_len > tlen) 177 goto invalid; 178 179 switch(vqp_obj_type) { 180 case VQP_OBJ_IP_ADDRESS: 181 if (vqp_obj_len != 4) 182 goto invalid; 183 ND_PRINT("%s (0x%08x)", GET_IPADDR_STRING(tptr), 184 GET_BE_U_4(tptr)); 185 break; 186 /* those objects have similar semantics - fall through */ 187 case VQP_OBJ_PORT_NAME: 188 case VQP_OBJ_VLAN_NAME: 189 case VQP_OBJ_VTP_DOMAIN: 190 case VQP_OBJ_ETHERNET_PKT: 191 nd_printjnp(ndo, tptr, vqp_obj_len); 192 break; 193 /* those objects have similar semantics - fall through */ 194 case VQP_OBJ_MAC_ADDRESS: 195 case VQP_OBJ_MAC_NULL: 196 if (vqp_obj_len != MAC_ADDR_LEN) 197 goto invalid; 198 ND_PRINT("%s", GET_ETHERADDR_STRING(tptr)); 199 break; 200 default: 201 if (ndo->ndo_vflag <= 1) 202 print_unknown_data(ndo,tptr, "\n\t ", vqp_obj_len); 203 break; 204 } 205 tptr += vqp_obj_len; 206 tlen -= vqp_obj_len; 207 nitems--; 208 } 209 return; 210 invalid: 211 nd_print_invalid(ndo); 212 } 213