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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  * support for the Cisco prop. VQP Protocol
     16  *
     17  * Original code by Carles Kishimoto <Carles.Kishimoto (at) bsc.es>
     18  */
     19 
     20 #define NETDISSECT_REWORKED
     21 #ifdef HAVE_CONFIG_H
     22 #include "config.h"
     23 #endif
     24 
     25 #include <tcpdump-stdinc.h>
     26 
     27 #include "interface.h"
     28 #include "extract.h"
     29 #include "addrtoname.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     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 
    117     /*
    118      * Sanity checking of the header.
    119      */
    120     if (VQP_EXTRACT_VERSION(vqp_common_header->version) != VQP_VERSION) {
    121 	ND_PRINT((ndo, "VQP version %u packet not supported",
    122                VQP_EXTRACT_VERSION(vqp_common_header->version)));
    123 	return;
    124     }
    125 
    126     /* in non-verbose mode just lets print the basic Message Type */
    127     if (ndo->ndo_vflag < 1) {
    128         ND_PRINT((ndo, "VQPv%u %s Message, error-code %s (%u), length %u",
    129                VQP_EXTRACT_VERSION(vqp_common_header->version),
    130                tok2str(vqp_msg_type_values, "unknown (%u)",vqp_common_header->msg_type),
    131                tok2str(vqp_error_code_values, "unknown (%u)",vqp_common_header->error_code),
    132 	       vqp_common_header->error_code,
    133                len));
    134         return;
    135     }
    136 
    137     /* ok they seem to want to know everything - lets fully decode it */
    138     nitems = vqp_common_header->nitems;
    139     ND_PRINT((ndo, "\n\tVQPv%u, %s Message, error-code %s (%u), seq 0x%08x, items %u, length %u",
    140            VQP_EXTRACT_VERSION(vqp_common_header->version),
    141 	   tok2str(vqp_msg_type_values, "unknown (%u)",vqp_common_header->msg_type),
    142 	   tok2str(vqp_error_code_values, "unknown (%u)",vqp_common_header->error_code),
    143 	   vqp_common_header->error_code,
    144            EXTRACT_32BITS(&vqp_common_header->sequence),
    145            nitems,
    146            len));
    147 
    148     /* skip VQP Common header */
    149     tptr+=sizeof(const struct vqp_common_header_t);
    150     tlen-=sizeof(const struct vqp_common_header_t);
    151 
    152     while (nitems > 0 && tlen > 0) {
    153 
    154         vqp_obj_tlv = (const struct vqp_obj_tlv_t *)tptr;
    155         vqp_obj_type = EXTRACT_32BITS(vqp_obj_tlv->obj_type);
    156         vqp_obj_len = EXTRACT_16BITS(vqp_obj_tlv->obj_length);
    157         tptr+=sizeof(struct vqp_obj_tlv_t);
    158         tlen-=sizeof(struct vqp_obj_tlv_t);
    159 
    160         ND_PRINT((ndo, "\n\t  %s Object (0x%08x), length %u, value: ",
    161                tok2str(vqp_obj_values, "Unknown", vqp_obj_type),
    162                vqp_obj_type, vqp_obj_len));
    163 
    164         /* basic sanity check */
    165         if (vqp_obj_type == 0 || vqp_obj_len ==0) {
    166             return;
    167         }
    168 
    169         /* did we capture enough for fully decoding the object ? */
    170         ND_TCHECK2(*tptr, vqp_obj_len);
    171 
    172         switch(vqp_obj_type) {
    173 	case VQP_OBJ_IP_ADDRESS:
    174             ND_PRINT((ndo, "%s (0x%08x)", ipaddr_string(ndo, tptr), EXTRACT_32BITS(tptr)));
    175             break;
    176             /* those objects have similar semantics - fall through */
    177         case VQP_OBJ_PORT_NAME:
    178 	case VQP_OBJ_VLAN_NAME:
    179 	case VQP_OBJ_VTP_DOMAIN:
    180 	case VQP_OBJ_ETHERNET_PKT:
    181             safeputs(ndo, tptr, vqp_obj_len);
    182             break;
    183             /* those objects have similar semantics - fall through */
    184 	case VQP_OBJ_MAC_ADDRESS:
    185 	case VQP_OBJ_MAC_NULL:
    186 	      ND_PRINT((ndo, "%s", etheraddr_string(ndo, tptr)));
    187               break;
    188         default:
    189             if (ndo->ndo_vflag <= 1)
    190                 print_unknown_data(ndo,tptr, "\n\t    ", vqp_obj_len);
    191             break;
    192         }
    193 	tptr += vqp_obj_len;
    194 	tlen -= vqp_obj_len;
    195 	nitems--;
    196     }
    197     return;
    198 trunc:
    199     ND_PRINT((ndo, "\n\t[|VQP]"));
    200 }
    201