sl@0: /*
sl@0: * Copyright (c) 2002-2009 Nokia Corporation and/or its subsidiary(-ies).
sl@0: * All rights reserved.
sl@0: * This component and the accompanying materials are made available
sl@0: * under the terms of the License "Eclipse Public License v1.0"
sl@0: * which accompanies this distribution, and is available
sl@0: * at the URL "http://www.eclipse.org/legal/epl-v10.html".
sl@0: *
sl@0: * Initial Contributors:
sl@0: * Nokia Corporation - initial contribution.
sl@0: *
sl@0: * Contributors:
sl@0: *
sl@0: * Description: 
sl@0: *
sl@0: */
sl@0: 
sl@0: 
sl@0: #include <cbcmode.h>
sl@0: 
sl@0: #include "cbcmodeshim.h"
sl@0: #include "../common/inlines.h"
sl@0: 
sl@0: void CBlockChainingMode::Reset()
sl@0: 	{
sl@0: 	iRegister.Copy(iIV);
sl@0: 	iBT->Reset();
sl@0: 	}
sl@0: 
sl@0: TInt CBlockChainingMode::BlockSize() const
sl@0: 	{
sl@0: 	return (iBT->BlockSize());
sl@0: 	}
sl@0: 
sl@0: TInt CBlockChainingMode::KeySize() const
sl@0: 	{
sl@0: 	return (iBT->KeySize());
sl@0: 	}
sl@0: 
sl@0: void CBlockChainingMode::SetIV(const TDesC8& aIV)
sl@0: 	{
sl@0: 	//We are making the stipulation that anybody calling SetIV is not setting it
sl@0: 	//to a longer IV than they originally did.  Otherwise SetIV needs to leave.
sl@0: 	assert(aIV.Size() <= iIV.Size());
sl@0: 	iIV.Copy(aIV);
sl@0: 	Reset();
sl@0: 	}
sl@0: 
sl@0: EXPORT_C CBlockChainingMode::CBlockChainingMode() 
sl@0: 	: iBT(NULL), iRegister(0,0,0), iIV(0,0,0)
sl@0: 	{
sl@0: 	}
sl@0: 
sl@0: EXPORT_C CBlockChainingMode::~CBlockChainingMode()
sl@0: 	{
sl@0: 	delete iBT;
sl@0: 	delete iRegisterBuf;
sl@0: 	delete iIVBuf;
sl@0: 	}
sl@0: 
sl@0: EXPORT_C void CBlockChainingMode::ConstructL(CBlockTransformation* aBT, const TDesC8& aIV)
sl@0: 	{
sl@0: 	iRegisterBuf = aIV.AllocL();
sl@0: 	iRegister.Set(iRegisterBuf->Des());
sl@0: 	iIVBuf = aIV.AllocL();
sl@0: 	iIV.Set(iIVBuf->Des());
sl@0: 
sl@0: 	// Take ownership last - doesn't take ownership if we leave
sl@0: 	iBT = aBT;
sl@0: 	}
sl@0: 
sl@0: /* CModeCBCEncryptor */
sl@0: EXPORT_C CModeCBCEncryptor* CModeCBCEncryptor::NewL(CBlockTransformation* aBT, 
sl@0: 	const TDesC8& aIV)
sl@0: 	{	
sl@0: 	CModeCBCEncryptor* self = CModeCBCEncryptorShim::NewL(aBT, aIV);
sl@0: 	if (! self)
sl@0: 		{			
sl@0: 		// not able to use CryptoSpi, possibly due to an exterally 
sl@0: 		// derived legacy class so fallback to old implementation.			
sl@0: 		self = NewLC(aBT,aIV);
sl@0: 		CleanupStack::Pop(self);
sl@0: 		}	
sl@0: 	return self;	
sl@0: 	}
sl@0: 
sl@0: EXPORT_C CModeCBCEncryptor* CModeCBCEncryptor::NewLC(CBlockTransformation* aBT,
sl@0: 	const TDesC8& aIV)
sl@0: 	{
sl@0: 	CModeCBCEncryptor* self = new (ELeave)CModeCBCEncryptor();	
sl@0: 	CleanupStack::PushL(self);
sl@0: 	self->ConstructL(aBT, aIV);
sl@0: 	return self;
sl@0: 	}
sl@0: 
sl@0: CModeCBCEncryptor::CModeCBCEncryptor()
sl@0: 	{
sl@0: 	}
sl@0: 
sl@0: void CModeCBCEncryptor::Transform(TDes8& aBlock)
sl@0: 	{
sl@0: 	assert(aBlock.Size() == iBT->BlockSize());
sl@0: 	assert(iRegister.Size() == aBlock.Size());
sl@0: 
sl@0: 	XorBuf(const_cast<TUint8*>(iRegister.Ptr()), aBlock.Ptr(), aBlock.Size());
sl@0: 	iBT->Transform(iRegister);
sl@0: 	aBlock.Copy(iRegister);
sl@0: 	}
sl@0: 
sl@0: /* CModeCBCDecryptor */
sl@0: EXPORT_C CModeCBCDecryptor* CModeCBCDecryptor::NewL(CBlockTransformation* aBT, 
sl@0: 	const TDesC8& aIV)
sl@0: 	{
sl@0: 	CModeCBCDecryptor* self = CModeCBCDecryptorShim::NewL(aBT, aIV);
sl@0: 	if (! self)
sl@0: 		{			
sl@0: 		// not able to use CryptoSpi, possibly due to an exterally 
sl@0: 		// derived legacy class so fallback to old implementation.			
sl@0: 		self = NewLC(aBT,aIV);
sl@0: 		CleanupStack::Pop(self);
sl@0: 		}	
sl@0: 	return self;	
sl@0: 	}
sl@0: 
sl@0: EXPORT_C CModeCBCDecryptor* CModeCBCDecryptor::NewLC(CBlockTransformation* aBT, 
sl@0: 	const TDesC8& aIV)
sl@0: 	{
sl@0: 	CModeCBCDecryptor* self = new (ELeave)CModeCBCDecryptor();	
sl@0: 	CleanupStack::PushL(self);
sl@0: 	self->ConstructL(aBT, aIV);
sl@0: 	return self;	
sl@0: 	}
sl@0: 
sl@0: void CModeCBCDecryptor::ConstructL(CBlockTransformation* aBT, const TDesC8& aIV)
sl@0: 	{
sl@0: 	iIVBakBuf = aIV.AllocL();
sl@0: 	iIVBak.Set(iIVBakBuf->Des());
sl@0: 	CBlockChainingMode::ConstructL(aBT, aIV);
sl@0: 	}
sl@0: 
sl@0: CModeCBCDecryptor::~CModeCBCDecryptor(void)
sl@0: 	{
sl@0: 	delete iIVBakBuf;
sl@0: 	}
sl@0: 
sl@0: CModeCBCDecryptor::CModeCBCDecryptor()
sl@0: 	: iIVBak(0,0,0)
sl@0: 	{
sl@0: 	}
sl@0: 
sl@0: void CModeCBCDecryptor::Transform(TDes8& aBlock)
sl@0: 	{
sl@0: 	assert(aBlock.Size() == iBT->BlockSize());
sl@0: 	assert(iRegister.Size() == aBlock.Size());
sl@0: 	assert(iIVBak.Size() == aBlock.Size());
sl@0: 	
sl@0: 	// Take a copy of incoming block
sl@0: 	iIVBak.Copy(aBlock);
sl@0: 
sl@0: 	// transform the block
sl@0: 	iBT->Transform(aBlock);
sl@0: 
sl@0: 	// xor the output with the register
sl@0: 	XorBuf(const_cast<TUint8*>(aBlock.Ptr()), iRegister.Ptr(), 
sl@0: 		aBlock.Size());
sl@0: 
sl@0: 	// Update the register to be the original block
sl@0: 	iRegister.Copy(iIVBak);
sl@0: }
sl@0: