/*
* Copyright (c) 1998-2006 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.
*
* Original code by Carles Kishimoto <[email protected]>
*/

/* \summary: Cisco VLAN Query Protocol (VQP) printer */

#include <sys/cdefs.h>
#ifndef lint
__RCSID("$NetBSD: print-vqp.c,v 1.9 2024/09/02 16:15:33 christos Exp $");
#endif

#include <config.h>

#include "netdissect-stdinc.h"

#define ND_LONGJMP_FROM_TCHECK
#include "netdissect.h"
#include "extract.h"
#include "addrtoname.h"

#define VQP_VERSION 1

/*
* VQP common header
*
*  0                   1                   2                   3
*  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
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* |   Constant    | Packet type   |  Error Code   |    nitems     |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* |                Packet Sequence Number (4 bytes)               |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/

struct vqp_common_header_t {
   nd_uint8_t  version;
   nd_uint8_t  msg_type;
   nd_uint8_t  error_code;
   nd_uint8_t  nitems;
   nd_uint32_t sequence;
};

struct vqp_obj_tlv_t {
   nd_uint32_t obj_type;
   nd_uint16_t obj_length;
};

#define VQP_OBJ_REQ_JOIN_PORT  0x01
#define VQP_OBJ_RESP_VLAN      0x02
#define VQP_OBJ_REQ_RECONFIRM  0x03
#define VQP_OBJ_RESP_RECONFIRM 0x04

static const struct tok vqp_msg_type_values[] = {
   { VQP_OBJ_REQ_JOIN_PORT, "Request, Join Port"},
   { VQP_OBJ_RESP_VLAN, "Response, VLAN"},
   { VQP_OBJ_REQ_RECONFIRM, "Request, Reconfirm"},
   { VQP_OBJ_RESP_RECONFIRM, "Response, Reconfirm"},
   { 0, NULL}
};

static const struct tok vqp_error_code_values[] = {
   { 0x00, "No error"},
   { 0x03, "Access denied"},
   { 0x04, "Shutdown port"},
   { 0x05, "Wrong VTP domain"},
   { 0, NULL}
};

/* FIXME the heading 0x0c looks ugly - those must be flags etc. */
#define VQP_OBJ_IP_ADDRESS    0x0c01
#define VQP_OBJ_PORT_NAME     0x0c02
#define VQP_OBJ_VLAN_NAME     0x0c03
#define VQP_OBJ_VTP_DOMAIN    0x0c04
#define VQP_OBJ_ETHERNET_PKT  0x0c05
#define VQP_OBJ_MAC_NULL      0x0c06
#define VQP_OBJ_MAC_ADDRESS   0x0c08

static const struct tok vqp_obj_values[] = {
   { VQP_OBJ_IP_ADDRESS, "Client IP Address" },
   { VQP_OBJ_PORT_NAME, "Port Name" },
   { VQP_OBJ_VLAN_NAME, "VLAN Name" },
   { VQP_OBJ_VTP_DOMAIN, "VTP Domain" },
   { VQP_OBJ_ETHERNET_PKT, "Ethernet Packet" },
   { VQP_OBJ_MAC_NULL, "MAC Null" },
   { VQP_OBJ_MAC_ADDRESS, "MAC Address" },
   { 0, NULL}
};

void
vqp_print(netdissect_options *ndo, const u_char *pptr, u_int len)
{
   const struct vqp_common_header_t *vqp_common_header;
   const struct vqp_obj_tlv_t *vqp_obj_tlv;

   const u_char *tptr;
   uint8_t version;
   uint16_t vqp_obj_len;
   uint32_t vqp_obj_type;
   u_int tlen;
   uint8_t nitems;

   ndo->ndo_protocol = "vqp";
   tptr=pptr;
   tlen = len;
   vqp_common_header = (const struct vqp_common_header_t *)pptr;
   ND_TCHECK_SIZE(vqp_common_header);
   if (sizeof(struct vqp_common_header_t) > tlen)
       goto invalid;
   version = GET_U_1(vqp_common_header->version);

   /*
    * Sanity checking of the header.
    */
   if (version != VQP_VERSION) {
       ND_PRINT("VQP version %u packet not supported",
              version);
       return;
   }

   /* in non-verbose mode just lets print the basic Message Type */
   if (ndo->ndo_vflag < 1) {
       ND_PRINT("VQPv%u %s Message, error-code %s (%u), length %u",
              version,
              tok2str(vqp_msg_type_values, "unknown (%u)",GET_U_1(vqp_common_header->msg_type)),
              tok2str(vqp_error_code_values, "unknown", GET_U_1(vqp_common_header->error_code)),
              GET_U_1(vqp_common_header->error_code),
              len);
       return;
   }

   /* ok they seem to want to know everything - lets fully decode it */
   nitems = GET_U_1(vqp_common_header->nitems);
   ND_PRINT("\n\tVQPv%u, %s Message, error-code %s (%u), seq 0x%08x, items %u, length %u",
          version,
          tok2str(vqp_msg_type_values, "unknown (%u)",GET_U_1(vqp_common_header->msg_type)),
          tok2str(vqp_error_code_values, "unknown", GET_U_1(vqp_common_header->error_code)),
          GET_U_1(vqp_common_header->error_code),
          GET_BE_U_4(vqp_common_header->sequence),
          nitems,
          len);

   /* skip VQP Common header */
   tptr+=sizeof(struct vqp_common_header_t);
   tlen-=sizeof(struct vqp_common_header_t);

   while (nitems != 0 && tlen != 0) {

       vqp_obj_tlv = (const struct vqp_obj_tlv_t *)tptr;
       ND_TCHECK_SIZE(vqp_obj_tlv);
       if (sizeof(struct vqp_obj_tlv_t) > tlen)
           goto invalid;
       vqp_obj_type = GET_BE_U_4(vqp_obj_tlv->obj_type);
       vqp_obj_len = GET_BE_U_2(vqp_obj_tlv->obj_length);
       tptr+=sizeof(struct vqp_obj_tlv_t);
       tlen-=sizeof(struct vqp_obj_tlv_t);

       ND_PRINT("\n\t  %s Object (0x%08x), length %u, value: ",
              tok2str(vqp_obj_values, "Unknown", vqp_obj_type),
              vqp_obj_type, vqp_obj_len);

       /* basic sanity check */
       if (vqp_obj_type == 0 || vqp_obj_len ==0) {
           return;
       }

       /* did we capture enough for fully decoding the object ? */
       ND_TCHECK_LEN(tptr, vqp_obj_len);
       if (vqp_obj_len > tlen)
           goto invalid;

       switch(vqp_obj_type) {
       case VQP_OBJ_IP_ADDRESS:
           if (vqp_obj_len != 4)
               goto invalid;
           ND_PRINT("%s (0x%08x)", GET_IPADDR_STRING(tptr),
                    GET_BE_U_4(tptr));
           break;
           /* those objects have similar semantics - fall through */
       case VQP_OBJ_PORT_NAME:
       case VQP_OBJ_VLAN_NAME:
       case VQP_OBJ_VTP_DOMAIN:
       case VQP_OBJ_ETHERNET_PKT:
           nd_printjnp(ndo, tptr, vqp_obj_len);
           break;
           /* those objects have similar semantics - fall through */
       case VQP_OBJ_MAC_ADDRESS:
       case VQP_OBJ_MAC_NULL:
           if (vqp_obj_len != MAC_ADDR_LEN)
               goto invalid;
             ND_PRINT("%s", GET_ETHERADDR_STRING(tptr));
             break;
       default:
           if (ndo->ndo_vflag <= 1)
               print_unknown_data(ndo,tptr, "\n\t    ", vqp_obj_len);
           break;
       }
       tptr += vqp_obj_len;
       tlen -= vqp_obj_len;
       nitems--;
   }
   return;
invalid:
   nd_print_invalid(ndo);
}

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