/*

* 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;

	}