#ifndef __CRYPTO_SHACOMMON_H_

#define __CRYPTO_SHACOMMON_H_

#include <e32base.h>/*

* Copyright (c) 2007-2009 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: 

* Same as used in SHA1

* SHA_CH		> CSHA1_F

* SHA_Maj		> CSHA1_H

* SHA_Parity	> CSHA1_G

* The following definitions are equivalent and potentially faster.

* #define SHA_Ch(x, y, z)      (((x) & ((y) ^ (z))) ^ (z))

* #define SHA_Maj(x, y, z)     (((x) & ((y) | (z))) | ((y) & (z)))

* These functions are defined in FIPS 180-2 Section 4.1

* Equation 4.1, 4.2, 4.3, 4.8, 4.9

*

*/

/**

 @file

 @internalComponent

 @released

*/

template<typename T>

inline T SHA_Ch(T aX, T aY, T aZ)

	{

	return ((aX & aY) ^ ((~aX) & aZ));

	}

template<typename T>

inline T SHA_Maj(T aX, T aY, T aZ)

	{

	return ((aX & aY) ^ (aX & aZ) ^ (aY & aZ));

	}

template<typename T>

inline T SHA_Parity(T aX, T aY, T aZ)

	{

	return (aX ^ aY ^ aZ);

	}

/**

 * Define the SHA shift, and rotate right macro 

 * Defined in FIPS 180-2 Section 3.2

 */

/** 

 * SHA Right Shift operation: The right shift operation SHR^n(x), 

 * where x is a w-bit word and n is an integer with 0 <= n < w, 

 * is defined by  SHR^n(x) = x >> n.

 */

template<typename T>

inline T SHA_SHR(T aBits, T aWord)

	{

	return (aWord >> aBits);

	}

/**

 * SHA Rotate Right Operation: The rotate right (circular right shift) operation

 * ROTR^n(x), where x is a w-bit word and n is an integer with 0 <= n < w, 

 * is defined by ROTR n(x)=(x >> n) || (x << w - n).

 */

template<typename T>

inline T SHA_ROTR(T aBits, T aWord)

	{

	TInt totalBits = sizeof(T) << 3;

	return ((aWord >> aBits) | (aWord << (totalBits-aBits)));

	}

NONSHARABLE_CLASS(MSHA2Impl)

	{

public:

	/**

	 * This function will reset the state of hash.

	 */

	virtual void Reset(const TAny*) = 0;

	/**

	 * This function will finalize the hash and return

	 * the calculated hash.

	 * @return Final hash

	 */ 

	virtual const TDesC8& Final() = 0;

	/**

	 * This function will add the message to the internal

	 * buffer and if the block size is reached then calcualte

	 * the hash till that point.

	 * @param aMessage Message to be updated.

	 * @param aLength Length of the message to be updated.

	 */ 

	virtual void Update(const TUint8* aMessage, TUint aLength) = 0;

	/**

	 * This function will save the internal state of the hash.

	 */ 

	virtual void StoreState() = 0;

	/**

	 * This function will retrieve the saved the internal state 

	 * of the hash.

	 */ 

	virtual void RestoreState() = 0;

	/**

	 * virtual distructor.

	 */

	virtual ~MSHA2Impl(){}

	};

#endif //__CRYPTO_SHACOMMON_H_