1 /*

     2 * Copyright (c) 2003-2009 Nokia Corporation and/or its subsidiary(-ies).

     3 * All rights reserved.

     4 * This component and the accompanying materials are made available

     5 * under the terms of the License "Eclipse Public License v1.0"

     6 * which accompanies this distribution, and is available

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

     8 *

     9 * Initial Contributors:

    10 * Nokia Corporation - initial contribution.

    11 *

    12 * Contributors:

    13 *

    14 * Description: 

    15 * CMontgomeryStructure class implementation

    16 *

    17 */

    18 

    19 

    20 /**

    21  @file 

    22  @internalComponent

    23 */

    24  

    25 #ifndef __MONT_H__

    26 #define __MONT_H__

    27 

    28 class TInteger;

    29 class RInteger;

    30 

    31 /** A special representation of integers allowing efficient multiplication

    32  * and exponentiation under special conditions.

    33  * @internalComponent

    34  */

    35 class CMontgomeryStructure : public CBase

    36 	{

    37 public:

    38 	static CMontgomeryStructure* NewL(const TInteger& aModulus);

    39 	IMPORT_C static CMontgomeryStructure* NewLC(const TInteger& aModulus);

    40 	~CMontgomeryStructure();

    41 	const TInteger& ReduceL(const TInteger& aInteger) const;

    42 	const TInteger& MultiplyL(const TInteger& aA, const TInteger& aB) const;

    43 	IMPORT_C const TInteger& ExponentiateL(const TInteger& aBase, const TInteger& aExponent) const;

    44 	const TInteger& SquareL(const TInteger& aA) const;

    45 protected:

    46 	void DoMultiplyL(TInteger& aResult, const TInteger& aA, const TInteger& aB) const;

    47 	void DoSquareL(TInteger& aResult, const TInteger& aA) const;

    48 	TInteger& ConvertIn(TInteger& aInteger) const;

    49 	TInteger& ConvertOutL(TInteger& aInteger) const;

    50 	CMontgomeryStructure();

    51 private:

    52 	void ConstructL(const TInteger& aModulus);

    53 	RInteger iModulus;

    54 	RInteger iModulusInv;

    55 	RInteger iWorkspace;

    56 	mutable RInteger iResult;

    57 	};

    58 

    59 #endif // __MONT_H__