/*

 * Copyright (c) 2003-2009 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: 

 *

 */

 #include <asymmetric.h>

 #include <asymmetrickeys.h>

 #include <bigint.h>

 #include <cryptostrength.h>

 #include <securityerr.h>

 #include <cryptopanic.h>

 #include "rsafunction.h"

 /* CRSAPKCS1v15Decryptor */

 EXPORT_C CRSAPKCS1v15Decryptor* CRSAPKCS1v15Decryptor::NewL(

 	const CRSAPrivateKey& aKey)

 	{

 	CRSAPKCS1v15Decryptor* self = NewLC(aKey);

 	CleanupStack::Pop(self);

 	return self;

 	}

 EXPORT_C CRSAPKCS1v15Decryptor* CRSAPKCS1v15Decryptor::NewLC(

 	const CRSAPrivateKey& aKey)

 	{

 	CRSAPKCS1v15Decryptor* self = new(ELeave) CRSAPKCS1v15Decryptor(aKey);

 	CleanupStack::PushL(self);

 	self->ConstructL();

 	return self;

 	}

 TInt CRSAPKCS1v15Decryptor::MaxInputLength(void) const

 	{

 	return iPrivateKey.N().ByteCount();

 	}

 TInt CRSAPKCS1v15Decryptor::MaxOutputLength(void) const

 	{

 	return MaxInputLength() - iPadding->MinPaddingLength();

 	}

 void CRSAPKCS1v15Decryptor::DecryptL(const TDesC8& aInput, 

 	TDes8& aOutput)const

 	{

 	__ASSERT_DEBUG(aOutput.MaxLength() >= MaxOutputLength(), User::Panic(KCryptoPanic, ECryptoPanicOutputDescriptorOverflow));

 	__ASSERT_DEBUG(aInput.Length() <= MaxInputLength(), User::Panic(KCryptoPanic, ECryptoPanicInputTooLarge));

 	RInteger input = RInteger::NewL(aInput);

 	CleanupStack::PushL(input);

 	RInteger output;

 	RSAFunction::DecryptL(iPrivateKey, input, output);

 	CleanupStack::PushL(output);

     TPtrC8 ptr = *(output.BufferLC());

     iPadding->UnPadL(ptr, aOutput);

     CleanupStack::PopAndDestroy(3, &input); //BufferLC(), output, input

 	}

 CRSAPKCS1v15Decryptor::CRSAPKCS1v15Decryptor(const CRSAPrivateKey& aKey)  

 	: iPrivateKey(aKey)

 	{

 	}

 void CRSAPKCS1v15Decryptor::ConstructL(void)  

 	{

 	iPadding = CPaddingPKCS1Encryption::NewL(MaxInputLength());

 	// Check if MaxInputLength() makes sense, if not the key length must 

 	// be too small

 	if(MaxOutputLength() <= 0)

 		{

 		User::Leave(KErrKeySize);

 		}

 	TCrypto::IsAsymmetricWeakEnoughL(iPrivateKey.N().BitCount());

 	}

 CRSAPKCS1v15Decryptor::~CRSAPKCS1v15Decryptor(void)  

 	{

 	delete iPadding;

 	}