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 (at) bsc.es> 16 */ 17 18 /* \summary: Cisco VLAN Query Protocol (VQP) printer */ 19 20 #ifdef HAVE_CONFIG_H 21 #include "config.h" 22 #endif 23 24 #include <netdissect-stdinc.h> 25 26 #include "netdissect.h" 27 #include "extract.h" 28 #include "addrtoname.h" 29 #include "ether.h" 30 31 #define VQP_VERSION 1 32 #define VQP_EXTRACT_VERSION(x) ((x)&0xFF) 33 34 /* 35 * VQP common header 36 * 37 * 0 1 2 3 38 * 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 39 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 40 * | Constant | Packet type | Error Code | nitems | 41 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 42 * | Packet Sequence Number (4 bytes) | 43 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 44 */ 45 46 struct vqp_common_header_t { 47 uint8_t version; 48 uint8_t msg_type; 49 uint8_t error_code; 50 uint8_t nitems; 51 uint8_t sequence[4]; 52 }; 53 54 struct vqp_obj_tlv_t { 55 uint8_t obj_type[4]; 56 uint8_t obj_length[2]; 57 }; 58 59 #define VQP_OBJ_REQ_JOIN_PORT 0x01 60 #define VQP_OBJ_RESP_VLAN 0x02 61 #define VQP_OBJ_REQ_RECONFIRM 0x03 62 #define VQP_OBJ_RESP_RECONFIRM 0x04 63 64 static const struct tok vqp_msg_type_values[] = { 65 { VQP_OBJ_REQ_JOIN_PORT, "Request, Join Port"}, 66 { VQP_OBJ_RESP_VLAN, "Response, VLAN"}, 67 { VQP_OBJ_REQ_RECONFIRM, "Request, Reconfirm"}, 68 { VQP_OBJ_RESP_RECONFIRM, "Response, Reconfirm"}, 69 { 0, NULL} 70 }; 71 72 static const struct tok vqp_error_code_values[] = { 73 { 0x00, "No error"}, 74 { 0x03, "Access denied"}, 75 { 0x04, "Shutdown port"}, 76 { 0x05, "Wrong VTP domain"}, 77 { 0, NULL} 78 }; 79 80 /* FIXME the heading 0x0c looks ugly - those must be flags etc. */ 81 #define VQP_OBJ_IP_ADDRESS 0x0c01 82 #define VQP_OBJ_PORT_NAME 0x0c02 83 #define VQP_OBJ_VLAN_NAME 0x0c03 84 #define VQP_OBJ_VTP_DOMAIN 0x0c04 85 #define VQP_OBJ_ETHERNET_PKT 0x0c05 86 #define VQP_OBJ_MAC_NULL 0x0c06 87 #define VQP_OBJ_MAC_ADDRESS 0x0c08 88 89 static const struct tok vqp_obj_values[] = { 90 { VQP_OBJ_IP_ADDRESS, "Client IP Address" }, 91 { VQP_OBJ_PORT_NAME, "Port Name" }, 92 { VQP_OBJ_VLAN_NAME, "VLAN Name" }, 93 { VQP_OBJ_VTP_DOMAIN, "VTP Domain" }, 94 { VQP_OBJ_ETHERNET_PKT, "Ethernet Packet" }, 95 { VQP_OBJ_MAC_NULL, "MAC Null" }, 96 { VQP_OBJ_MAC_ADDRESS, "MAC Address" }, 97 { 0, NULL} 98 }; 99 100 void 101 vqp_print(netdissect_options *ndo, register const u_char *pptr, register u_int len) 102 { 103 const struct vqp_common_header_t *vqp_common_header; 104 const struct vqp_obj_tlv_t *vqp_obj_tlv; 105 106 const u_char *tptr; 107 uint16_t vqp_obj_len; 108 uint32_t vqp_obj_type; 109 u_int tlen; 110 uint8_t nitems; 111 112 tptr=pptr; 113 tlen = len; 114 vqp_common_header = (const struct vqp_common_header_t *)pptr; 115 ND_TCHECK(*vqp_common_header); 116 if (sizeof(struct vqp_common_header_t) > tlen) 117 goto trunc; 118 119 /* 120 * Sanity checking of the header. 121 */ 122 if (VQP_EXTRACT_VERSION(vqp_common_header->version) != VQP_VERSION) { 123 ND_PRINT((ndo, "VQP version %u packet not supported", 124 VQP_EXTRACT_VERSION(vqp_common_header->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((ndo, "VQPv%u %s Message, error-code %s (%u), length %u", 131 VQP_EXTRACT_VERSION(vqp_common_header->version), 132 tok2str(vqp_msg_type_values, "unknown (%u)",vqp_common_header->msg_type), 133 tok2str(vqp_error_code_values, "unknown (%u)",vqp_common_header->error_code), 134 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 = vqp_common_header->nitems; 141 ND_PRINT((ndo, "\n\tVQPv%u, %s Message, error-code %s (%u), seq 0x%08x, items %u, length %u", 142 VQP_EXTRACT_VERSION(vqp_common_header->version), 143 tok2str(vqp_msg_type_values, "unknown (%u)",vqp_common_header->msg_type), 144 tok2str(vqp_error_code_values, "unknown (%u)",vqp_common_header->error_code), 145 vqp_common_header->error_code, 146 EXTRACT_32BITS(&vqp_common_header->sequence), 147 nitems, 148 len)); 149 150 /* skip VQP Common header */ 151 tptr+=sizeof(const struct vqp_common_header_t); 152 tlen-=sizeof(const 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(*vqp_obj_tlv); 158 if (sizeof(struct vqp_obj_tlv_t) > tlen) 159 goto trunc; 160 vqp_obj_type = EXTRACT_32BITS(vqp_obj_tlv->obj_type); 161 vqp_obj_len = EXTRACT_16BITS(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((ndo, "\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_TCHECK2(*tptr, vqp_obj_len); 176 if (vqp_obj_len > tlen) 177 goto trunc; 178 179 switch(vqp_obj_type) { 180 case VQP_OBJ_IP_ADDRESS: 181 if (vqp_obj_len != 4) 182 goto trunc; 183 ND_PRINT((ndo, "%s (0x%08x)", ipaddr_string(ndo, tptr), EXTRACT_32BITS(tptr))); 184 break; 185 /* those objects have similar semantics - fall through */ 186 case VQP_OBJ_PORT_NAME: 187 case VQP_OBJ_VLAN_NAME: 188 case VQP_OBJ_VTP_DOMAIN: 189 case VQP_OBJ_ETHERNET_PKT: 190 safeputs(ndo, tptr, vqp_obj_len); 191 break; 192 /* those objects have similar semantics - fall through */ 193 case VQP_OBJ_MAC_ADDRESS: 194 case VQP_OBJ_MAC_NULL: 195 if (vqp_obj_len != ETHER_ADDR_LEN) 196 goto trunc; 197 ND_PRINT((ndo, "%s", etheraddr_string(ndo, tptr))); 198 break; 199 default: 200 if (ndo->ndo_vflag <= 1) 201 print_unknown_data(ndo,tptr, "\n\t ", vqp_obj_len); 202 break; 203 } 204 tptr += vqp_obj_len; 205 tlen -= vqp_obj_len; 206 nitems--; 207 } 208 return; 209 trunc: 210 ND_PRINT((ndo, "\n\t[|VQP]")); 211 } 212
