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      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 
     30 #define VQP_VERSION            		1
     31 #define VQP_EXTRACT_VERSION(x) ((x)&0xFF)
     32 
     33 /*
     34  * VQP common header
     35  *
     36  *  0                   1                   2                   3
     37  *  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
     38  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     39  * |   Constant    | Packet type   |  Error Code   |    nitems     |
     40  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     41  * |                Packet Sequence Number (4 bytes)               |
     42  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     43  */
     44 
     45 struct vqp_common_header_t {
     46     uint8_t version;
     47     uint8_t msg_type;
     48     uint8_t error_code;
     49     uint8_t nitems;
     50     uint8_t sequence[4];
     51 };
     52 
     53 struct vqp_obj_tlv_t {
     54     uint8_t obj_type[4];
     55     uint8_t obj_length[2];
     56 };
     57 
     58 #define VQP_OBJ_REQ_JOIN_PORT  0x01
     59 #define VQP_OBJ_RESP_VLAN      0x02
     60 #define VQP_OBJ_REQ_RECONFIRM  0x03
     61 #define VQP_OBJ_RESP_RECONFIRM 0x04
     62 
     63 static const struct tok vqp_msg_type_values[] = {
     64     { VQP_OBJ_REQ_JOIN_PORT, "Request, Join Port"},
     65     { VQP_OBJ_RESP_VLAN, "Response, VLAN"},
     66     { VQP_OBJ_REQ_RECONFIRM, "Request, Reconfirm"},
     67     { VQP_OBJ_RESP_RECONFIRM, "Response, Reconfirm"},
     68     { 0, NULL}
     69 };
     70 
     71 static const struct tok vqp_error_code_values[] = {
     72     { 0x00, "No error"},
     73     { 0x03, "Access denied"},
     74     { 0x04, "Shutdown port"},
     75     { 0x05, "Wrong VTP domain"},
     76     { 0, NULL}
     77 };
     78 
     79 /* FIXME the heading 0x0c looks ugly - those must be flags etc. */
     80 #define VQP_OBJ_IP_ADDRESS    0x0c01
     81 #define VQP_OBJ_PORT_NAME     0x0c02
     82 #define VQP_OBJ_VLAN_NAME     0x0c03
     83 #define VQP_OBJ_VTP_DOMAIN    0x0c04
     84 #define VQP_OBJ_ETHERNET_PKT  0x0c05
     85 #define VQP_OBJ_MAC_NULL      0x0c06
     86 #define VQP_OBJ_MAC_ADDRESS   0x0c08
     87 
     88 static const struct tok vqp_obj_values[] = {
     89     { VQP_OBJ_IP_ADDRESS, "Client IP Address" },
     90     { VQP_OBJ_PORT_NAME, "Port Name" },
     91     { VQP_OBJ_VLAN_NAME, "VLAN Name" },
     92     { VQP_OBJ_VTP_DOMAIN, "VTP Domain" },
     93     { VQP_OBJ_ETHERNET_PKT, "Ethernet Packet" },
     94     { VQP_OBJ_MAC_NULL, "MAC Null" },
     95     { VQP_OBJ_MAC_ADDRESS, "MAC Address" },
     96     { 0, NULL}
     97 };
     98 
     99 void
    100 vqp_print(netdissect_options *ndo, register const u_char *pptr, register u_int len)
    101 {
    102     const struct vqp_common_header_t *vqp_common_header;
    103     const struct vqp_obj_tlv_t *vqp_obj_tlv;
    104 
    105     const u_char *tptr;
    106     uint16_t vqp_obj_len;
    107     uint32_t vqp_obj_type;
    108     int tlen;
    109     uint8_t nitems;
    110 
    111     tptr=pptr;
    112     tlen = len;
    113     vqp_common_header = (const struct vqp_common_header_t *)pptr;
    114     ND_TCHECK(*vqp_common_header);
    115 
    116     /*
    117      * Sanity checking of the header.
    118      */
    119     if (VQP_EXTRACT_VERSION(vqp_common_header->version) != VQP_VERSION) {
    120 	ND_PRINT((ndo, "VQP version %u packet not supported",
    121                VQP_EXTRACT_VERSION(vqp_common_header->version)));
    122 	return;
    123     }
    124 
    125     /* in non-verbose mode just lets print the basic Message Type */
    126     if (ndo->ndo_vflag < 1) {
    127         ND_PRINT((ndo, "VQPv%u %s Message, error-code %s (%u), length %u",
    128                VQP_EXTRACT_VERSION(vqp_common_header->version),
    129                tok2str(vqp_msg_type_values, "unknown (%u)",vqp_common_header->msg_type),
    130                tok2str(vqp_error_code_values, "unknown (%u)",vqp_common_header->error_code),
    131 	       vqp_common_header->error_code,
    132                len));
    133         return;
    134     }
    135 
    136     /* ok they seem to want to know everything - lets fully decode it */
    137     nitems = vqp_common_header->nitems;
    138     ND_PRINT((ndo, "\n\tVQPv%u, %s Message, error-code %s (%u), seq 0x%08x, items %u, length %u",
    139            VQP_EXTRACT_VERSION(vqp_common_header->version),
    140 	   tok2str(vqp_msg_type_values, "unknown (%u)",vqp_common_header->msg_type),
    141 	   tok2str(vqp_error_code_values, "unknown (%u)",vqp_common_header->error_code),
    142 	   vqp_common_header->error_code,
    143            EXTRACT_32BITS(&vqp_common_header->sequence),
    144            nitems,
    145            len));
    146 
    147     /* skip VQP Common header */
    148     tptr+=sizeof(const struct vqp_common_header_t);
    149     tlen-=sizeof(const struct vqp_common_header_t);
    150 
    151     while (nitems > 0 && tlen > 0) {
    152 
    153         vqp_obj_tlv = (const struct vqp_obj_tlv_t *)tptr;
    154         vqp_obj_type = EXTRACT_32BITS(vqp_obj_tlv->obj_type);
    155         vqp_obj_len = EXTRACT_16BITS(vqp_obj_tlv->obj_length);
    156         tptr+=sizeof(struct vqp_obj_tlv_t);
    157         tlen-=sizeof(struct vqp_obj_tlv_t);
    158 
    159         ND_PRINT((ndo, "\n\t  %s Object (0x%08x), length %u, value: ",
    160                tok2str(vqp_obj_values, "Unknown", vqp_obj_type),
    161                vqp_obj_type, vqp_obj_len));
    162 
    163         /* basic sanity check */
    164         if (vqp_obj_type == 0 || vqp_obj_len ==0) {
    165             return;
    166         }
    167 
    168         /* did we capture enough for fully decoding the object ? */
    169         ND_TCHECK2(*tptr, vqp_obj_len);
    170 
    171         switch(vqp_obj_type) {
    172 	case VQP_OBJ_IP_ADDRESS:
    173             ND_PRINT((ndo, "%s (0x%08x)", ipaddr_string(ndo, tptr), EXTRACT_32BITS(tptr)));
    174             break;
    175             /* those objects have similar semantics - fall through */
    176         case VQP_OBJ_PORT_NAME:
    177 	case VQP_OBJ_VLAN_NAME:
    178 	case VQP_OBJ_VTP_DOMAIN:
    179 	case VQP_OBJ_ETHERNET_PKT:
    180             safeputs(ndo, tptr, vqp_obj_len);
    181             break;
    182             /* those objects have similar semantics - fall through */
    183 	case VQP_OBJ_MAC_ADDRESS:
    184 	case VQP_OBJ_MAC_NULL:
    185 	      ND_PRINT((ndo, "%s", etheraddr_string(ndo, tptr)));
    186               break;
    187         default:
    188             if (ndo->ndo_vflag <= 1)
    189                 print_unknown_data(ndo,tptr, "\n\t    ", vqp_obj_len);
    190             break;
    191         }
    192 	tptr += vqp_obj_len;
    193 	tlen -= vqp_obj_len;
    194 	nitems--;
    195     }
    196     return;
    197 trunc:
    198     ND_PRINT((ndo, "\n\t[|VQP]"));
    199 }
    200