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 "3des.h"
sl@0: #include "../common/inlines.h"
sl@0: #include "des.inl"
sl@0: #include <cryptostrength.h>
sl@0: 
sl@0: const TInt K3DESBlockBytes = 8;
sl@0: const TInt K3DESKeyBytes = 24;
sl@0: const TInt KDESKeyBytes = 8;
sl@0: 
sl@0: void C3DES::Transform(TDes8& aBlock)
sl@0: 	{
sl@0: 	assert(aBlock.Size() == K3DESBlockBytes);
sl@0: 		
sl@0: 	TUint32 l, r;
sl@0: //	Split the block into 2 word-sized big endian portions
sl@0: 	GetBlockBigEndian((TUint8*)&aBlock[0], l, r);
sl@0: 
sl@0: 	IPerm(l,r);
sl@0: 
sl@0: 	DoTransform(l, r, iK1);
sl@0: 	DoTransform(r, l, iK2);
sl@0: 	DoTransform(l, r, iK3);
sl@0: 		
sl@0: 	FPerm(l,r);
sl@0: 
sl@0: //	Put the portions back into the block as little endian
sl@0: 	PutBlockBigEndian((TUint8*)&aBlock[0], r, l);
sl@0: 	}
sl@0: 
sl@0: TInt C3DES::BlockSize() const
sl@0: 	{
sl@0: 	return K3DESBlockBytes;
sl@0: 	}
sl@0: 
sl@0: TInt C3DES::KeySize() const
sl@0: 	{
sl@0: 	return K3DESKeyBytes;
sl@0: 	}
sl@0: 
sl@0: C3DES::C3DES()
sl@0: 	{
sl@0: 	}
sl@0: 
sl@0: void C3DES::ConstructL(const TDesC8& aKey)
sl@0: 	{
sl@0: 	assert(aKey.Size() == K3DESKeyBytes);
sl@0: 
sl@0: 	iKey = aKey.AllocL();
sl@0: 	DoSetKey(*iKey);
sl@0: 	}
sl@0: 
sl@0: void C3DES::Reset()
sl@0: 	{
sl@0: 	DoSetKey(*iKey);
sl@0: 	}
sl@0: 
sl@0: /* C3DESEncryptor */
sl@0: 
sl@0: EXPORT_C C3DESEncryptor* C3DESEncryptor::NewL(const TDesC8& aKey)
sl@0: 	{
sl@0: 	C3DESEncryptor* me = C3DESEncryptor::NewLC(aKey);
sl@0: 	CleanupStack::Pop(me);
sl@0: 	return (me);	
sl@0: 	}
sl@0: 
sl@0: EXPORT_C C3DESEncryptor* C3DESEncryptor::NewLC(const TDesC8& aKey)
sl@0: 	{
sl@0: 	C3DESEncryptor* me = new (ELeave) C3DESEncryptor();
sl@0: 	CleanupStack::PushL(me);
sl@0: 	me->ConstructL(aKey);
sl@0: 	// DES only used 7 bits out of every key byte
sl@0: 	TCrypto::IsSymmetricWeakEnoughL(BytesToBits(aKey.Size()) - aKey.Size());
sl@0: 	return (me);	
sl@0: 	}
sl@0: 
sl@0: void C3DESEncryptor::DoSetKey(const TDesC8& aKey)
sl@0: 	{
sl@0: 	// Encryptor key	
sl@0: 	SetKey(aKey.Mid(0, KDESKeyBytes), iK1);
sl@0: 	// Decryptor key
sl@0: 	SetKey(aKey.Mid(KDESKeyBytes, 2*KDESKeyBytes), iK2);
sl@0: 	ReverseKeySchedule(iK2); // Reverse key schedule order
sl@0: 	// Encryptor key
sl@0: 	SetKey(aKey.Mid(2*KDESKeyBytes), iK3);
sl@0: 	}
sl@0:  
sl@0: /* C3DESDecryptor */
sl@0: 
sl@0: EXPORT_C C3DESDecryptor* C3DESDecryptor::NewL(const TDesC8& aKey)
sl@0: 	{
sl@0: 	C3DESDecryptor* me = C3DESDecryptor::NewLC(aKey);
sl@0: 	CleanupStack::Pop(me);
sl@0: 	return (me);
sl@0: 	}
sl@0: 
sl@0: EXPORT_C C3DESDecryptor* C3DESDecryptor::NewLC(const TDesC8& aKey)
sl@0: 	{
sl@0: 	C3DESDecryptor* me = new (ELeave) C3DESDecryptor();
sl@0: 	CleanupStack::PushL(me);
sl@0: 	me->ConstructL(aKey);
sl@0: 	// DES only used 7 bits out of every key byte
sl@0: 	TCrypto::IsSymmetricWeakEnoughL(BytesToBits(aKey.Size()) - aKey.Size());
sl@0: 	return (me);
sl@0: 	}
sl@0: 
sl@0: void C3DESDecryptor::DoSetKey(const TDesC8& aKey)
sl@0: 	{
sl@0: 	// 3DES decryption, reverse through key
sl@0: 	// Decryptor key
sl@0: 	CDES::SetKey(aKey.Mid(2*KDESKeyBytes), iK1);
sl@0: 	ReverseKeySchedule(iK1);	//	Reverse key schedule order	
sl@0: 
sl@0: 	// Encryptor key
sl@0: 	CDES::SetKey(aKey.Mid(KDESKeyBytes, 2*KDESKeyBytes), iK2);
sl@0: 	
sl@0: 	// Decryptor key
sl@0: 	CDES::SetKey(aKey.Mid(0, KDESKeyBytes), iK3);
sl@0: 	ReverseKeySchedule(iK3);	//	Reverse key schedule order
sl@0: 	}
sl@0: