sl@0: /*
sl@0: * Copyright (c) 2007-2010 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 "dhkeypairshim.h"
sl@0: #include <bigint.h>
sl@0: #include <cryptospi/cryptokeypairgeneratorapi.h>
sl@0: #include <cryptospi/keypair.h>
sl@0: #include <cryptospi/cryptoparams.h>
sl@0: #include <cryptospi/cryptospidef.h>
sl@0: 
sl@0: 
sl@0: using namespace CryptoSpi;
sl@0: 
sl@0: 
sl@0: /* CDHKeyPair */
sl@0: CDHKeyPairShim* CDHKeyPairShim::NewLC(RInteger& aN, RInteger& aG)
sl@0: 	{
sl@0: 	CDHKeyPairShim* self = new(ELeave) CDHKeyPairShim();
sl@0: 	CleanupStack::PushL(self);
sl@0: 	self->ConstructL(aN, aG);
sl@0: 	return self;
sl@0: 	}
sl@0: 
sl@0: CDHKeyPairShim* CDHKeyPairShim::NewLC(RInteger& aN, RInteger& aG, RInteger& ax)
sl@0: 	{
sl@0: 	CDHKeyPairShim* self = new(ELeave) CDHKeyPairShim();
sl@0: 	CleanupStack::PushL(self);
sl@0: 	self->ConstructL(aN, aG, ax);
sl@0: 	return self;
sl@0: 	}
sl@0: 
sl@0: CDHKeyPairShim::~CDHKeyPairShim(void)
sl@0: 	{
sl@0: 	}
sl@0: 
sl@0: CDHKeyPairShim::CDHKeyPairShim(void)
sl@0: 	{
sl@0: 	}	
sl@0: 
sl@0: void CDHKeyPairShim::ConstructL(RInteger& aN, RInteger& aG)
sl@0: 	{
sl@0: 	RInteger x = RInteger::NewL();
sl@0: 	CleanupClosePushL(x);
sl@0: 	KeyConstructorL(aN, aG, x, EFalse);
sl@0: 	CleanupStack::PopAndDestroy(1, &x);
sl@0: 	}
sl@0: 
sl@0: void CDHKeyPairShim::ConstructL(RInteger& aN, RInteger& aG, RInteger& ax)
sl@0: 	{
sl@0: 	KeyConstructorL(aN, aG, ax, ETrue);
sl@0: 	}
sl@0: 
sl@0: void CDHKeyPairShim::KeyConstructorL(RInteger& aN, RInteger& aG, RInteger& ax, TBool xIncluded)
sl@0: 	{
sl@0: 	RInteger& nminus2 = aN;
sl@0: 	
sl@0: 	/*
sl@0: 	 * do some sanity checks
sl@0: 	 */
sl@0: 	--nminus2;
sl@0: 	--nminus2;
sl@0: 	if( aG < TInteger::Two() || aG > nminus2 )
sl@0: 		{
sl@0: 		User::Leave(KErrArgument);
sl@0: 		}
sl@0: 
sl@0: 	if (xIncluded)
sl@0: 		{
sl@0: 		if( ax < TInteger::One() || ax > nminus2 )
sl@0: 			{
sl@0: 			User::Leave(KErrArgument);
sl@0: 			}
sl@0: 		}
sl@0: 
sl@0: 	/*
sl@0: 	 *find out how big the key should be - the key must be in the range x | 1 <= x <= n-2
sl@0: 	 * nminus2 is the largest the key can be so get the number of bits required to represent that number
sl@0: 	 */
sl@0: 	const TInt keySize = nminus2.BitCount();
sl@0: 
sl@0: 	// increment aN back to its original value
sl@0: 	++nminus2;
sl@0: 	++nminus2;
sl@0: 
sl@0: 	// obtain an RSA key pair generator interface
sl@0: 	
sl@0: 	CKeyPairGenerator* keyPairGeneratorImpl=NULL;
sl@0: 	CKeyPairGeneratorFactory::CreateKeyPairGeneratorL(
sl@0: 											keyPairGeneratorImpl,
sl@0: 											KDHKeyPairGeneratorUid,
sl@0: 											NULL);
sl@0: 	CleanupStack::PushL(keyPairGeneratorImpl);
sl@0: 	
sl@0: 	/* 
sl@0: 	 * put the DH parameters into an array
sl@0: 	 */
sl@0: 	CCryptoParams* keyParameters = CCryptoParams::NewLC();
sl@0: 	keyParameters->AddL(aN, KDhKeyParameterNUid);
sl@0: 	keyParameters->AddL(aG, KDhKeyParameterGUid);
sl@0: 	if (xIncluded)
sl@0: 		{
sl@0: 		// the private key x has been supplied so add it to the params array so the key generator algo can use it
sl@0: 		keyParameters->AddL(ax, KDhKeyParameterxUid);
sl@0: 		ax.Close();
sl@0: 		}
sl@0: 
sl@0: 	/* 
sl@0: 	 * call the api to create a DH key pair
sl@0: 	 */
sl@0: 	CKeyPair* keyPair = 0;
sl@0: 	keyPairGeneratorImpl->GenerateKeyPairL(keySize, *keyParameters, keyPair);
sl@0: 	CleanupStack::PushL(keyPair);
sl@0: 
sl@0: 	/* 
sl@0: 	 * for compatibility convert the CKeyPair to CDHPrivateKey and CDHPublicKey
sl@0: 	 */
sl@0: 
sl@0: 	// create new RInteger copies of aN, aG and x so the private key can own them
sl@0: 	RInteger NCopy = RInteger::NewL(aN);
sl@0: 	CleanupClosePushL(NCopy);
sl@0: 	RInteger GCopy = RInteger::NewL(aG);
sl@0: 	CleanupClosePushL(GCopy);
sl@0: 	RInteger x = RInteger::NewL(keyPair->PrivateKey().GetBigIntL(KDhKeyParameterxUid));
sl@0: 	CleanupClosePushL(x);
sl@0: 	iPrivate = CDHPrivateKey::NewL(NCopy, GCopy, x);
sl@0: 	CleanupStack::Pop(3, &NCopy);
sl@0: 	
sl@0: 	// the public key becomes the owner of aN, aG and X
sl@0: 	RInteger X = RInteger::NewL(keyPair->PublicKey().GetBigIntL(KDhKeyParameterXUid));
sl@0: 	CleanupClosePushL(X);
sl@0: 	iPublic = CDHPublicKey::NewL(aN, aG, X);
sl@0: 	CleanupStack::Pop(&X);	
sl@0: 
sl@0: 	/* 
sl@0: 	 * cleanup stack - it should contain keyPairGeneratorImpl, keyParameters, keyPair, X, NCopy, GCopy and x
sl@0: 	 */	
sl@0: 	CleanupStack::PopAndDestroy(3, keyPairGeneratorImpl);
sl@0: 	}