// Copyright (c) 2008-2009 Nokia Corporation and/or its subsidiary(-ies).

// All rights reserved.

// This component and the accompanying materials are made available

// under the terms of "Eclipse Public License v1.0"

// which accompanies this distribution, and is available

// at the URL "http://www.eclipse.org/legal/epl-v10.html".

//

// Initial Contributors:

// Nokia Corporation - initial contribution.

//

// Contributors:

//

// Description:

// This file consists of implementation of DNS Proxy engine. This is the controller

// class which reads configuration from resolver.ini, configures DNS Proxy components

// and starts and stops the listener.

//

/**

 @file

 @internalTechnology

*/

#include <es_sock.h>

#include <cflog.h>

#include "e32debug.h"

#include "dnsproxylistener.h"

#include "dnsproxyengine.h"

#include "dnsproxyservconf.h"

#include "dnsproxylog.h"

#include "inet6log.h"

//intializing the static object

CDnsProxyEngine* CDnsProxyEngine::iDnsProxyEngine = NULL;

CDnsProxyEngine* CDnsProxyEngine::NewL()

/**

 * This is the two phase construction method and is leaving function

 * @param - None

 * @return - None

 *

 * @internalTechnology

 */

	{

	__LOG("\n CDnsProxyEngine::NewL Entry")

	CDnsProxyEngine* pEngine = new(ELeave)CDnsProxyEngine();

	CleanupStack::PushL(pEngine);

	pEngine->ConstructL();

	CleanupStack::Pop();

	__LOG("\n CDnsProxyEngine::NewL Exit")

	return pEngine;

	}

CDnsProxyEngine::CDnsProxyEngine()

/**

 * This is the constructor for this class

 * @param - None

 * @return - None

 *

 * @internalTechnology

 */

	{

	__LOG("\n CDnsProxyEngine::CDnsProxyEngine Entry")

	iConfigData = NULL;

	iConfigDataErr = 0;

	__LOG("\n  CDnsProxyEngine::CDnsProxyEngine Exit")

	}

/* This is the destructor  and deletes all the member variables and thus

 * releases all the memory assosicated with those objects

 */

CDnsProxyEngine::~CDnsProxyEngine()

/**

 * This is the destructor  and deletes all the member variables and thus

 * releases all the memory assosicated with those objects

 * @param - None

 * @return - None

 *

 * @internalTechnology

 **/

	{

	__LOG("\n CDnsProxyEngine::~CDnsProxyEngine Entry")

	delete iConfigData;

	delete iProxyServer;

	delete iListener;

	delete iDnsproxydb;

	iSockServ.Close();

	__LOG("\n CDnsProxyEngine::~CDnsProxyEngine Exit")

	}

/* This is second phase construction where in all objects will be created

 * which potentially may leave due to resource problem

 */

void CDnsProxyEngine::ConstructL()

/**

 * This is the second phase of construction.

 * Create intances of proxy database, config server and listener classes.

 * Reads configuration values from .ini file

 * @param - None

 * @return - None

 *

 * @internalTechnology

 **/

	{

	__LOG("\n CDnsProxyEngine::ConstructL Entry")

	//Reads the configuration from .ini file

	ReadConfiguration();

	User::LeaveIfError(iSockServ.Connect());

	__LOG("After Reading configuration")

	iDnsproxydb = CDnsProxyDb::CreateInstanceL(*this);

	iProxyServer = CDnsServerConfig::NewL(*this);

	iListener    = CDnsProxyListener::NewL(*this);

	__LOG("\n CDnsProxyEngine::ConstructL Exit")

	}

/* This is function reads configuration values from configuration file

 *

 */

void CDnsProxyEngine::ReadConfiguration()

/**

 *

 * This method reads configuration values from .ini file

 * @param - None

 * @return - None

 *

 * @internalTechnology

 **/

	{

	__LOG("\n CDnsProxyEngine::ReadConfiguration Entry")

	iConfigParams.iSessionCount = GetIniValue(DNS_PROXY_INI_SECTION,DNS_PROXY_INI_NUM_SOCK_SESSION,KSessioncount);

	iConfigParams.iRetryCount   = GetIniValue(DNS_PROXY_INI_SECTION,DNS_PROXY_INI_NUM_RETRIES,KRetrycount);

	iConfigParams.iQSize        = GetIniValue(DNS_PROXY_INI_SECTION,DNS_PROXY_INI_QUEUE_SIZE,KQSize);

	iConfigParams.iTTL          = GetIniValue(DNS_PROXY_INI_SECTION,DNS_PROXY_INI_TTL,KTtl);

	iConfigParams.iDbSize       = GetIniValue(DNS_PROXY_INI_SECTION,DNS_PROXY_INI_DB_SIZE,KDbSize);

	iConfigParams.iTimerVal     = GetIniValue(DNS_PROXY_INI_SECTION,DNS_PROXY_INI_TIMER_VAL,KTimerVal);

	iConfigParams.iSerialNum    = GetIniValue(DNS_PROXY_INI_SECTION,DNS_PROXY_INI_SERIAL_NUM,KSerialNum);

	iConfigParams.iRefreshTime  = GetIniValue(DNS_PROXY_INI_SECTION,DNS_PROXY_INI_REFRESH_TIME,KRefreshTime);

	iConfigParams.iRetryTime    = GetIniValue(DNS_PROXY_INI_SECTION,DNS_PROXY_INI_RETRY_TIME,KRetryTime);

	iConfigParams.iExpiretime   = GetIniValue(DNS_PROXY_INI_SECTION,DNS_PROXY_INI_EXPIRE_TIME,KExpireTime);	

	__LOG1("\n CDnsProxyEngine::ReadConfiguration iSessionCount (%d)",iConfigParams.iSessionCount)

	__LOG1("\n CDnsProxyEngine::ReadConfiguration iRetryCount (%d)",iConfigParams.iRetryCount)

	__LOG1("\n CDnsProxyEngine::ReadConfiguration iTimerVal (%d)",iConfigParams.iTimerVal)

	UnLoadConfigurationFile();

	}

TInt CDnsProxyEngine::Start(const RMessage2& aMessage)

/**

 * This is entry point of DNS Proxy functionality. The DHCP server session

 * calls this using client API to start dnsproxy.

 * @param aMessage - Message send by the client

 * @return - None

 *

 * @internalTechnology

 **/

	{

    TInt err;

	__LOG("\n CDnsProxyEngine::Start Entry")

	err = SetDlinkConnectionInfo(aMessage);

	if(err!=KErrNone)

		return err;

	err = iListener->Activate();

	__LOG("\n CDnsProxyEngine::ReadConfiguration Exit")

	return err;

	}

void CDnsProxyEngine::Stop()

/**

 * This stops the listener and deletes all the objects.The method is called at the time

 * of shutdown.

 * @param - None

 * @return - None

 *

 * @internalTechnology

 **/

	{

	__LOG("\n CDnsProxyEngine::Stop Entry")

	iListener->StopListener();

	__LOG("\n CDnsProxyEngine::Stop Exit")

	}

TBool CDnsProxyEngine::FindVar(const TDesC &aSection, const TDesC &aVarName, TInt &aResult)

/**

 * This will find specified value for variable in the configuation file

 * @param aSection - represents the section name in configuration file

 * @param aVarName - represents name in the specified section

 * @param aResult - sets the corresponding values for above given varname

 * @return - returns the boolean flag - if name value pair or loading configuration

 * 			- fails then returns false

 * @panic - system wide errors

 *

 * @internalTechnology

 **/

	{

	__LOG("\n DnsProxyEngine::FindVar")

	if(LoadConfigurationFile())

	  {

	   ASSERT(iConfigData);	// <-- lint gag

	   return iConfigData->FindVar(aSection, aVarName, aResult);

	  }

	__LOG("\n DnsProxyEngine::FindVar Exit")

	return EFalse;

	}

TBool CDnsProxyEngine::LoadConfigurationFile()

/**

 * This will load the configuaration file into memory.

 * If it is already loaded then returns true otherwise loads the file

 * @param - None

 * @return boolean - retursn boolean value either true or false

 *

 * @internalTechnology

 **/

	{

	__LOG("\n CDnsProxyEngine::LoadConfigurationFile Entry")

	if (iConfigData)

		return TRUE;	// Already loaded!

	if (iConfigDataErr)

		return FALSE;

	TRAP(iConfigDataErr, iConfigData = CESockIniData::NewL(DNS_PROXY_INI_DATA));

	__LOG("\n CDnsProxyEngine::LoadConfigurationFile Exit")

	return (iConfigData != NULL);

	}

void CDnsProxyEngine::UnLoadConfigurationFile()

/**

 * This will unload the configuaration file from memory.

 * @param - None

 * @return - None

 *

 * @internalTechnology

 **/

	{

	__LOG("\n CDnsProxyEngine::UnloadConfigurationFile Entry")

	delete iConfigData;

	iConfigData = NULL;

	iConfigDataErr = 0;

	__LOG("\n CDnsProxyEngine::UnloadConfigurationFile Exit")

	}

TInt CDnsProxyEngine::GetIniValue(const TDesC &aSection, const TDesC &aName, TInt aValue)

/**

 * This function reads the value for given name in the specified section

 * @param aSection - represents the section name in configuration file

 * @param aName - represents name in specified section

 * @param aValue - represents default value

 * @return boolean - retursn boolean value either true or false

 *

 * @internalTechnology

 **/

	{

	__LOG("\n CDnsProxyEngine::GetIniValue Entry")

	LOG(_LIT(KFormat, "\t[%S] %S = %d"));

	TInt value;

	if (!FindVar(aSection, aName, value))

		value = aValue;

    LOG(Log::Printf(KFormat, &aSection, &aName, value));

    __LOG1("CDnsProxyEngine::GetIniValue %d",value);

	return value;

	}

TInt CDnsProxyEngine::AddDbEntryL(const RMessage2& aMsg)

/**

 * This method updates DB.

 * @param aMessage - Message send by the client

 * @return - None

 *

 * @internalTechnology

 **/

	{

	if(!iDnsproxydb)

	   return KErrBadHandle;

	TBuf8<KMaxName> dbdata;

	TBuf16<KAddrLength> ipaddress;

	aMsg.Read(0,ipaddress);

	aMsg.Read(1,dbdata);

	TInetAddr address;

    address.Input(ipaddress);

    TInt current_size = iDnsproxydb->GetDbSize();

    if(current_size < iConfigParams.iDbSize)

    	{

  		iDnsproxydb->UpdateDbL(dbdata,address);

    	}

    else

	    {

	    return KErrGeneral;	

	    }	

	__LOG("\n CDnsProxyEngine::AddDbEntryL Exit")

	return KErrNone;

	}

TInt CDnsProxyEngine::RemoveDbEntry(const RMessage2& aMsg)

/**

 * This method updates DB.

 * @param aMessage - Message send by the client

 * @return - None

 *

 * @internalTechnology

 **/

	{

	if(!iDnsproxydb)

		return KErrBadHandle;

	__LOG("\n CDnsProxyEngine::RemoveDbEntry Entry")

	TBuf16<KAddrLength> ipaddress;

	aMsg.Read(0,ipaddress);

	TInetAddr address;

    address.Input(ipaddress);

    iDnsproxydb->DeleteDbEntry(address);

    __LOG("\n CDnsProxyEngine::RemoveDbEntry Exit")

    return KErrNone;

	}

void CDnsProxyEngine::UpdateLocalAddr(TInetAddr& aAddr)

/**

 * This method updates interface address in the engine.

 * @param addr - Listen interface address

 * @return - None

 *

 * @internalTechnology

 **/

	{

	__LOG("\n CDnsProxyEngine::UpdateLocalAddr Entry/Exit")

	iProxyIfAddr = aAddr;

	}

TInt CDnsProxyEngine::UpdateDomainInfo(const RMessage2& aMsg)

/**

 * This method updates DB.

 * @param aMessage - Message send by the client

 * @return - None

 *

 * @internalTechnology

 **/

	{

	TInt err = KErrNone;

	__LOG("\n CDnsProxyEngine::UpdateDomainInfo Entry")

	err = aMsg.Read(0,iSuffixInfo);

	return err;

	}

TInt CDnsProxyEngine::IsSuffixAvailable()

/**

 * This method checks if suffix is available. 

 * @param  None

 * @return Length- Length of suffix data

 *

 * @internalTechnology

 **/

	{

	__LOG("\n CDnsProxyEngine::IsSuffixAvailable Entry/Exit")

	return iSuffixInfo.Length();

	}

CDnsProxyEngine* CDnsProxyEngine::GetInstanceL()

    {

/**

 * This method returns single ton pointer to CDnsProxyEngine 

 * @param  None

 * @return iUplinkConnection

 *

 * @internalTechnology

 **/    

    __LOG("\n CDnsProxyEngine::GetInstanceL Entry")    

    if(!iDnsProxyEngine)

        {

        __LOG("\n first time creation ")            

        iDnsProxyEngine = CDnsProxyEngine::NewL();

        }

    __LOG("\n CDnsProxyEngine::GetInstanceL  Exit")        

    return iDnsProxyEngine;

    }

TInt CDnsProxyEngine::SetUplinkConnectionInfo(const RMessage2 &aMessage)

/**

 * This method reads uplink connection info from the message. 

 * @param aMessage - Message send by the client

 * @return - None

 *

 * @internalTechnology

 **/

	{

	__LOG("\n CDnsProxyEngine::SetUplinkConnectionInfo Entry")

	TInt err = iListener->SetUplinkConnectionInfo(aMessage);

	__LOG("\n CDnsProxyEngine::SetUplinkConnectionInfo Exit")

	return err;

    }

TInt CDnsProxyEngine::SetDlinkConnectionInfo(const RMessage2 &aMessage)

/**

 * This method reads downlink connection info from the message. 

 * @param aMessage - Message send by the client

 * @return - None

 *

 * @internalTechnology

 **/

	{

	__LOG("\n CDnsProxyEngine::SetDlinkConnectionInfo Entry")

	TInt err = iListener->SetDlinkConnectionInfo(aMessage);

	__LOG("\n CDnsProxyEngine::SetDlinkConnectionInfo End")

	return err;

	}