/*

 * Copyright (c) 2002-2009 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 "tmontgomeryfb.h"

 #include "t_input.h"

 #include "t_output.h"

 #include "tutils.h"

 #include <bigint.h>

 #include <random.h>

 #include "../../source/bigint/mont.h"

 CTestAction* CMontgomeryFB::NewL(RFs& aFs, CConsoleBase& aConsole, 

 	Output& aOut, const TTestActionSpec& aTestActionSpec)

 	{

 	CTestAction* self = CMontgomeryFB::NewLC(aFs, aConsole,

 		aOut, aTestActionSpec);

 	CleanupStack::Pop();

 	return self;

 	}

 CTestAction* CMontgomeryFB::NewLC(RFs& aFs, CConsoleBase& aConsole, 

 	Output& aOut, const TTestActionSpec& aTestActionSpec)

 	{

 	CMontgomeryFB* self = new(ELeave) CMontgomeryFB(aFs, aConsole, aOut);

 	CleanupStack::PushL(self);

 	self->ConstructL(aTestActionSpec);

 	return self;

 	}

 CMontgomeryFB::~CMontgomeryFB()

 	{

 	delete iBody;

 	}

 CMontgomeryFB::CMontgomeryFB(RFs& aFs, CConsoleBase& aConsole, Output& aOut)

 	: CTestAction(aConsole, aOut), iFs(aFs)

 	{

 	}

 void CMontgomeryFB::ConstructL(const TTestActionSpec& aTestActionSpec)

 	{

 	CTestAction::ConstructL(aTestActionSpec);

 	iBody = HBufC8::NewL(aTestActionSpec.iActionBody.Length());

 	iBody->Des().Copy(aTestActionSpec.iActionBody);

 	HBufC8* length = Input::ParseElementHexL(*iBody, _L8("<bits>"));

 	CleanupStack::PushL(length);

 	RInteger clength = RInteger::NewL(*length);

 	CleanupStack::PopAndDestroy(length);

 	CleanupStack::PushL(clength);

 	TUint bits = clength.ConvertToLongL();

 	CleanupStack::PopAndDestroy();//clength

 	// the final /7 gives the number of times we have to increment by 7 to get

 	// to that number of bytes and hence bits.

 	iIterations = ((bits+7)/8)/7 + 1;

 	}

 void CMontgomeryFB::DoPerformPrerequisite(TRequestStatus& aStatus)

 	{

 	TRequestStatus* status = &aStatus;

 	User::RequestComplete(status, KErrNone);

 	iActionState = CTestAction::EAction;

 	}

 void CMontgomeryFB::DoPerformPostrequisite(TRequestStatus& aStatus)

 	{

 	TRequestStatus* status = &aStatus;

 	iFinished = ETrue;

 	User::RequestComplete(status, KErrNone);

 	}

 void CMontgomeryFB::DoReportAction(void)

 	{

 	}

 void CMontgomeryFB::DoCheckResult(TInt)

 	{

 	}

 void CMontgomeryFB::PerformAction(TRequestStatus& aStatus)

 	{

 	TRAPD(res, PerformActionL());

 	__ASSERT_ALWAYS(!res, User::Panic(_L("CMontgomeryFB::PerformAction"), res));

 	TRequestStatus* status = &aStatus;

 	User::RequestComplete(status, KErrNone);

 	iActionState = CTestAction::EPostrequisite;

 	}

 void CMontgomeryFB::PerformActionL()

 	{

 	__UHEAP_MARK;

 	iResult = ETrue;

 	//Generate iIterations*7 byte random sequences we are using 7 as it's a

 	//generator mod 8.  Thus we'll cycle through every value (0-7) every 8

 	//iterations.  This gives us a better feeling that certain byte lengths

 	//(and thus bit lengths as the byte is chosen randomly) don't have errors.

 	for(TUint i=1; i<=iIterations; i++)

 		{ 

 		//generate a prime of roughly i*7*8 bits

 		RInteger prime = RInteger::NewPrimeL(i*7*8);

 		CleanupStack::PushL(prime);

 		CMontgomeryStructure* mont = CMontgomeryStructure::NewLC(prime);

 		//generate a random number of x | 2 < x < prime

 		RInteger base = RInteger::NewRandomL(TInteger::Two(), prime);

 		CleanupStack::PushL(base);

 		//This is using Fermat's Little Theorem

 		//  (base ^ prime) % prime == base or

 		//  (base ^ prime-1) % prime == 1

 		const TInteger& y = mont->ExponentiateL(base, prime);

 		if( y != base )

 			{

 			iResult = EFalse;

 			iConsole.Printf(_L("X"));

 			iOut.writeString(_L("Failure exponentiating:"));

 			iOut.writeNewLine();

 			Utils::DumpInteger(iOut, _L("base: "), base);

 			Utils::DumpInteger(iOut, _L("prime: "), prime);

 			Utils::DumpInteger(iOut, _L("output: "), (const RInteger&)y);

 			Utils::DumpInteger(iOut, _L("expected: "), base);

 			}

 		CleanupStack::PopAndDestroy(3, &prime);//base,mont,prime

 		iConsole.Printf(_L("."));

 		}

 	__UHEAP_MARKEND;

 	}