/*

* Copyright (c) 2007-2009 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: 

*

*/

/**

 @file

 @internalTechnology

*/

#include "symmetriccipherstepbase.h"

#include <bigint.h>

/**

Common setup of a crypto SPI symmetric cipher.

@param aArc4Check Determines whether the check is run on the cipher type for ARC4 and if it matches, sets up the CCryptoParams accordingly.

@param aRc2Check Determines whether the check is run on the cipher type for RC2 and if it matches, sets up the CCryptoParams accordingly.

@param aOperationMode On return is the operation mode read in from the config file and used in the initial setup of the cipher.

@param aCipher On return the symmetric cipher implementation.

@param aKey On return aCipher's key object.  This is should not be deleted until after aCipher is deleted.

@return The error value from the call to the symmetric cipher creation function.

*/

void CSymmetricCipherStepBase::SetupCipherL(TBool aArc4Check, TBool aRc2Check, TVariantPtrC& aOperationMode, CSymmetricCipher*& aCipher, CKey*& aKey)

	{	

	TPtrC keyPath;

	TVariantPtrC algorithm;

	TVariantPtrC paddingMode;

	if(	!GetStringFromConfig(ConfigSection(),KConfigEncryptKey, keyPath) ||

		!GetStringFromConfig(ConfigSection(),KConfigAlgorithmUid, algorithm) || 

		!GetStringFromConfig(ConfigSection(),KConfigOperationMode, aOperationMode) ||

		!GetStringFromConfig(ConfigSection(),KConfigPaddingMode, paddingMode ))

		{

		User::Leave(KErrNotFound);

		}

	// Create key 

	TKeyProperty keyProperty;

	CCryptoParams* params = CCryptoParams::NewLC(); 

	CFileReader* keyData = CFileReader::NewLC(keyPath);

	params->AddL( *keyData, KSymmetricKeyParameterUid);

	aKey=CKey::NewL(keyProperty, *params);

	CleanupStack::PushL(aKey);

	CCryptoParams* xparams = NULL;	

	if ((aArc4Check) && (TUid(algorithm) == KArc4Uid))

		{

		// Set the RC4 DiscardBytes to 0

		xparams = CCryptoParams::NewLC();

		xparams->AddL(NULL, KARC4DiscardBytes);

		// Create a Symmetric Cipher with the values from the ini file

		CSymmetricCipherFactory::CreateSymmetricCipherL(aCipher, algorithm, *aKey, KCryptoModeEncryptUid, aOperationMode, paddingMode, xparams);

		CleanupStack::PopAndDestroy(xparams);

		CleanupStack::Pop(aKey);

		CleanupStack::PopAndDestroy(2, params);

		}

	else if ((aRc2Check) && (TUid(algorithm) == KRc2Uid))

		{

		TInt keylen = TPtrC8(*keyData).Length() * 8;

		xparams = CCryptoParams::NewLC();

		// Set the RC2 EffectiveKeyLen according to the input key size

		xparams->AddL( keylen, KRC2EffectiveKeyLenBits);

		// Create a Symmetric Cipher with the values from the ini file

		CSymmetricCipherFactory::CreateSymmetricCipherL(aCipher, algorithm, *aKey, KCryptoModeEncryptUid, aOperationMode, paddingMode, xparams);

		CleanupStack::PopAndDestroy(xparams);

		CleanupStack::Pop(aKey);

		CleanupStack::PopAndDestroy(2, params);

		}

	else

		{

		// Create a Symmetric Cipher with the values from the ini file

		CSymmetricCipherFactory::CreateSymmetricCipherL(aCipher, algorithm, *aKey, KCryptoModeEncryptUid, aOperationMode, paddingMode, xparams);

		CleanupStack::Pop(aKey);

		CleanupStack::PopAndDestroy(2, params);

		}

	}

/**

When running in CTR mode call this function to calculate the block size of a cipher.

@param aCipher The cipher whose block size is returned.

@return The block size in bits.

*/	

TInt CSymmetricCipherStepBase::CtrModeCalcBlockSizeL(CSymmetricCipher& aCipher)

	{

  	// aCipher MUST be running in CTR mode

	aCipher.SetOperationModeL(KOperationModeCBCUid);

	TInt blockSize = aCipher.BlockSize();

	aCipher.SetOperationModeL(KOperationModeCTRUid);

	return blockSize;	

	}

/**

Read in the plaintext from the course file listed in the configuration file.

@param aPlaintext Descriptor pointing to the plaintext.

@param aReader This CFileReader pointer must be NULL when passed in. It must not be deleted until after the client has finished with the plaintext.

*/	

HBufC8* CSymmetricCipherStepBase::ReadInPlaintextL()

	{

	TPtrC plaintextPath;

	if(!GetStringFromConfig(ConfigSection(),KConfigSourcePath, plaintextPath))

		{

		User::Leave(KErrNotFound);

		}

	return ReadFileL(plaintextPath);

	}

/**

Read in the ciphertext from the course file listed in the configuration file.

@param aCiphertext Descriptor pointing to the ciphertext.

@param aReader This CFileReader pointer must be NULL when passed in. It must not be deleted until after the client has finished with the ciphertext.

*/

HBufC8* CSymmetricCipherStepBase::ReadInCiphertextL()

	{

	TPtrC ciphertextPath;

	if(!GetStringFromConfig(ConfigSection(),KConfigEncryptedPath, ciphertextPath))

		{

		User::Leave(KErrNotFound);

		}

	return ReadFileL(ciphertextPath);

	}

/**

Read in the IV from the course file listed in the configuration file.

@param aIV Descriptor pointing to the IV.

@param aReader This CFileReader pointer must be NULL when passed in. It must not be deleted until after the client has finished with the IV.

*/

HBufC8* CSymmetricCipherStepBase::ReadInIvL()

	{

	TPtrC ivPath;

	if(!GetStringFromConfig(ConfigSection(),KConfigIVPath, ivPath))

		{

		User::Leave(KErrNotFound);

		}

	return ReadFileL(ivPath);

	}

/**

@param aCounter

*/	

HBufC8* CSymmetricCipherStepBase::CtrModeIncrementCounterL(TDesC8& aCounter)

	{

	RInteger bigInt = RInteger::NewL(aCounter);

	CleanupClosePushL(bigInt);

	++bigInt;

	HBufC8* result = bigInt.BufferLC();

	CleanupStack::Pop(result);

	CleanupStack::PopAndDestroy();

	return result;

	}

HBufC8* CSymmetricCipherStepBase::ReadInHexCiphertextL()

	{

	HBufC8* hex = ReadInCiphertextL();

	CleanupStack::PushL(hex);

	HBufC8* result = ConvertFromHexFormatToRawL((*hex));

	CleanupStack::PopAndDestroy(hex);

	return result;

	}

HBufC8* CSymmetricCipherStepBase::ReadInHexPlaintextL()

	{

	HBufC8* hex = ReadInPlaintextL();

	CleanupStack::PushL(hex);

	HBufC8* result = ConvertFromHexFormatToRawL((*hex));

	CleanupStack::PopAndDestroy(hex);

	return result;

	}	

HBufC8* CSymmetricCipherStepBase::ReadInHexPlainTextL(TPtrC aFile)

	{

	HBufC8* data = ReadFileL(aFile);

	CleanupStack::PushL(data);

	HBufC8* result = ConvertFromHexFormatToRawL(*data);

	CleanupStack::PopAndDestroy(data);

	return result;

	}	

HBufC8* CSymmetricCipherStepBase::ReadFileL(TPtrC aFile)

	{

	CFileReader* reader = CFileReader::NewL(aFile);

	CleanupStack::PushL(reader);

	TPtrC8 ptr(*reader);

	HBufC8* fileData = ptr.AllocL();

	CleanupStack::PopAndDestroy(reader);

	return fileData;

	}

HBufC8* CSymmetricCipherStepBase::ReadInHexIvL()

	{

	HBufC8* hex = ReadInIvL();

	CleanupStack::PushL(hex);

	HBufC8* result = ConvertFromHexFormatToRawL((*hex));

	CleanupStack::PopAndDestroy(hex);

	return result;

	}

HBufC8* CSymmetricCipherStepBase::ConvertFromHexFormatToRawL(TDesC8& aInput)

	{

	TBuf8<2> hexPair;

	HBufC8* result = HBufC8::NewLC(aInput.Length()/2);

	TUint8 val;

	for(TInt i = 0 ; i < aInput.Length()-1 ; i+=2)

		{

		hexPair = aInput.Mid(i,2);

		TLex8 lex(hexPair);

		User::LeaveIfError(lex.Val(val, EHex));

		result->Des().Append(val);			

		}

	CleanupStack::Pop(result);

	return result;	

	}