/*

* Copyright (c) 2002-2009 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: 

* ** IMPORTANT ** PublishedPartner API's in this file are published to 3rd party developers via the 

* Symbian website. Changes to these API's should be treated as PublishedAll API changes and the Security TA should be consulted.

* RC2 implementation

*

*/

/**

 @file 

 @publishedPartner

 @released 

*/

#ifndef __RC2_H__

#define __RC2_H__

#include <blocktransformation.h>

#ifndef SYMBIAN_ENABLE_SPLIT_HEADERS

/** OpenSSL PKCS8 Effective Key Length Compatibility.*/

const TUint KPkcs8CompatibilityBits = 128;

/** PKCS12 PBE Effective Key Length Compatibility.*/

const TUint KPkcs12CompatibilityBits = 40;

#endif

/** The expanded key length of an RC2 key.*/

const TUint KRC2ExpandedKeyLen = 64;

/** SSL Effective Key Length Compatibility.*/

const TUint KSSLCompatibilityBits = 1024;

/** The maximum size in bytes for a RC2 key.*/

const TUint KRC2MaxKeySizeBytes = 128;	//	Max key size in this implementation = 128 bytes

/**

* Abstract base class for RC2 encipherment.

*

*/

class CRC2 : public CBlockTransformation

{

public:	

	virtual void Reset();

	virtual TInt BlockSize() const;

	virtual TInt KeySize() const;

protected:

	/** @internalAll */

	CRC2(void);

	virtual void SetKey(const TDesC8& aKey, TInt aEffectiveKeyLenBits);

protected:

	/**

	 * The expanded key buffer.

	 *

	 * Each iK[i] is a 16-bit word.

	 */

	TUint16 iK[KRC2ExpandedKeyLen];	//	128 bytes

	/** 

	 * The input key

	 * 

	 * The key length must fall between 1 and KRC2MaxKeySizeBytes (=128) bytes inclusive.

	 */

	TBuf8<KRC2MaxKeySizeBytes> iKey;

	/** The effective key length in bits */

	TInt iEffectiveKeyLenBits;

};

/**

* Concrete class for RC2 encryption.

*

*/

class CRC2Encryptor : public CRC2

{

public:

	/**

	* Creates an instance of this class.

	*

	* @param aKey					The key to be used for encryption. The key length must fall between 

	*								1 and KRC2MaxKeySizeBytes (=128) bytes inclusive.

	* @param aEffectiveKeyLenBits	Effective key length bits

	*								(defaults KSSLCompatibilityBits = 1024).

	*

	* @leave KErrKeyNotWeakEnough	If the key size is larger than that allowed by the

	*								cipher strength restrictions of the crypto library.

	*								See TCrypto::IsSymmetricWeakEnoughL()

	*/

	IMPORT_C static CRC2Encryptor* NewL(const TDesC8& aKey, 

		TInt aEffectiveKeyLenBits = KSSLCompatibilityBits);

	/**

	* Creates an instance of this class and leaves it on the cleanup stack.

	*

	* @param aKey					The key to be used for encryption. The key length must fall between 

	*								1 and KRC2MaxKeySizeBytes (=128) bytes inclusive.

	* @param aEffectiveKeyLenBits	Effective key length bits 

	*								(defaults KSSLCompatibilityBits = 1024).

	*

	* @leave KErrKeyNotWeakEnough	If the key size is larger than that allowed by the

	*								cipher strength restrictions of the crypto library.

	*								See TCrypto::IsSymmetricWeakEnoughL()

	*/

	IMPORT_C static CRC2Encryptor* NewLC(const TDesC8& aKey, 

		TInt aEffectiveKeyLenBits = KSSLCompatibilityBits);

	virtual void Transform(TDes8& aBlock);

protected:

	/** @internalAll */

	CRC2Encryptor(void);

};

/**

* Concrete class for RC2 decryption.

*

*/

class CRC2Decryptor : public CRC2

{

public:

	/**

	* Creates an instance of this class.

	*

	* @param aKey					The key to be used for decryption. The key length must fall between 

	*								1 and KRC2MaxKeySizeBytes (=128) bytes inclusive.

	* @param aEffectiveKeyLenBits	Effective key length bits 

	*								(defaults KSSLCompatibilityBits = 1024).

	*

	* @leave KErrKeyNotWeakEnough	If the key size is larger than that allowed by the

	*								cipher strength restrictions of the crypto library.

	*								See TCrypto::IsSymmetricWeakEnoughL()

	*/

	IMPORT_C static CRC2Decryptor* NewL(const TDesC8& aKey, 

		TInt aEffectiveKeyLenBits = KSSLCompatibilityBits);

	/**

	* Creates an instance of this class and leaves it on the cleanup stack.

	*

	* @param aKey					The key to be used for decryption. The key length must fall between 

	*								1 and KRC2MaxKeySizeBytes (=128) bytes inclusive.

	* @param aEffectiveKeyLenBits	Effective key length bits 

	*								(defaults KSSLCompatibilityBits = 1024).

	*

	* @leave KErrKeyNotWeakEnough	If the key size is larger than that allowed by the

	*								cipher strength restrictions of the crypto library.

	*								See TCrypto::IsSymmetricWeakEnoughL()

	*/

	IMPORT_C static CRC2Decryptor* NewLC(const TDesC8& aKey, 

		TInt aEffectiveKeyLenBits = KSSLCompatibilityBits);

	virtual void Transform(TDes8& aBlock);

protected:

	/** @internalAll */

	CRC2Decryptor(void);

};

#endif	//	__RC2_H__