/*

 * 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 the License "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: 

 * Cipher MAC plugin implementation

 *

 */

 /**

  @file

  @internalComponent

  @released

 */

 #ifndef __CRYPTOAPI_SOFTWARECIPHERMACIMPL_H__

 #define __CRYPTOAPI_SOFTWARECIPHERMACIMPL_H__

 #include "cryptosymmetriccipherapi.h"

 #include "keys.h"

 namespace SoftwareCrypto

 	{

 	using namespace CryptoSpi;

 	/**

 	 * This is the maximum block size in bytes currently supported by CMAC implementation.

 	 * 

 	 * The cipher based algorithms currently supported are

 	 * AES-XCBC-MAC-96 and AES-XCBC-PRF-128.

 	 */  

 	const TInt KMacBlockSize = 16;		

 	/** 

 	 * The class is created from following substance classes

 	 * 1. MMac

 	 * 2. CSymmetricCipher

 	 * Using the methods of the above classes we will transform/mould the Cipher methods in

 	 * a way as to be inline with the MMac interface methods. The MMac methods will

 	 * serve as the wrapper internal to which Cipher methods will work to provide the MAC value.

 	 * 

 	 * The class was created to provide consistency/similarity HMAC and CMAC works.

 	 * Also for future extensibility of other Cipher algorithms.

 	 */		

 	NONSHARABLE_CLASS(CCMacImpl) : public CBase

 		{		

 	public:

 		/**

 		 * Cipher MAC implementation instance creation methods

 		 *

 		 *The owneship of 'aSymmetricCipher' is imparted to instance of this class.

 		 */

 		static CCMacImpl* NewL(const CKey& aKey,

 			        		   CSymmetricCipher* aSymmetricCipher,	

 				               TInt32 aAlgorithmUid);

 		static CCMacImpl* NewLC(const CKey& aKey, 

 							    CSymmetricCipher* aSymmetricCipher,	

 							    TInt32 aAlgorithmUid);

 		/**

 		 * Simulating Methods from MPlugin

 		 */

 		const CExtendedCharacteristics* GetExtendedCharacteristicsL();

 		// We will call CSymmetricBlockCipherImpl::Reset();

 		void Reset();

 		/**

 		 *  Simulating MAC interfaces (Software based)

 		 */

 	    TPtrC8 MacL(const TDesC8& aMessage);

         void UpdateL(const TDesC8& aMessage);

         TPtrC8 FinalL(const TDesC8& aMessage);

 		void ReInitialiseAndSetKeyL(const CKey& aKey);    

 		void SetKeyL(const CKey& aKey);

 		~CCMacImpl();

 		CCMacImpl* CopyL();

 		CCMacImpl* ReplicateL();

 	private:

 	    /**

 		 * Constructors

 		 */

     	CCMacImpl(CryptoSpi::CSymmetricCipher* aSymmetricCipher);

 		CCMacImpl(const CCMacImpl&);

 		/**

 		 * Initialize the 'iCipherImpl' instances.

 		 */

 		void ConstructL(const CKey& aKey, TInt32 aAlgorithmUid);

 		void DoUpdateL(const TDesC8& aMessage);

 		TPtrC8 DoFinalL();

 		void PadMessage();

 		void ProcessBlockL();

 		void XORKeyWithData(const TDesC8& aKey, TDes8& aOutput);

 		CKey* Create128bitKeyL(const CKey& aKey);		

 	private:			

 		TInt32 iImplementationUid; 

 		CKey* iKey;

 		CryptoSpi::CSymmetricCipher* iCipherImpl;

 		TBuf8<KMacBlockSize> iKey1;

 		TBuf8<KMacBlockSize> iKey2;

 		TBuf8<KMacBlockSize> iKey3;

 		TBuf8<KMacBlockSize> iMacValue;

 		TUint8 iE[KMacBlockSize];

 		TUint8 iData[KMacBlockSize];

 		TInt iCurrentTotalLength;

 		// Resets the cipher with iE(128 zero bits) the next time MacL, 

 		// UpdateL or FinalL are called. This was introduced as we cannot leave from the

 		// non-leaving CCMacImpl::Reset() implementation of the MPlugin::Reset() pure 

 		// virtual. To prevent behavioral break.

 		TInt iDelayedReset;

 		};

 	}

 #endif // __CRYPTOAPI_SOFTWARECIPHERMACIMPL_H__