--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/cryptoplugins/cryptospiplugins/source/softwarecrypto/dhimpl.cpp	Fri Nov 06 13:21:00 2009 +0200
@@ -0,0 +1,105 @@
+/*
+* Copyright (c) 2006-2009 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 "dhimpl.h"
+#include "pluginconfig.h"
+
+using namespace SoftwareCrypto;
+using namespace CryptoSpi;
+
+/* CDHImpl */
+CDHImpl::CDHImpl()
+	{
+	}
+
+CDHImpl::~CDHImpl()
+	{
+	}
+
+CDHImpl* CDHImpl::NewL(const CKey& aPrivateKey, const CCryptoParams* aParams)
+	{
+	CDHImpl* self = CDHImpl::NewLC(aPrivateKey, aParams);
+	CleanupStack::Pop(self);
+	return self;
+	}
+
+CDHImpl* CDHImpl::NewLC(const CKey& aPrivateKey, const CCryptoParams* aParams)
+	{
+	CDHImpl* self = new(ELeave) CDHImpl();
+	CleanupStack::PushL(self);
+	self->ConstructL(aPrivateKey, aParams);
+	return self;
+	}
+
+CKey* CDHImpl::AgreeL(const CKey& aOtherPublicKey, const CCryptoParams* aParams)
+	{
+	/*
+	 * unpack the parameters, we're expecting the N and G parameters
+	 */
+	const TInteger& N = aParams->GetBigIntL(KDhKeyParameterNUid);
+	const TInteger& G = aParams->GetBigIntL(KDhKeyParameterGUid);
+	const TInteger& privateN = iSharedParams->GetBigIntL(KDhKeyParameterNUid);
+	const TInteger& privateG = iSharedParams->GetBigIntL(KDhKeyParameterGUid);
+	const TInteger& X = aOtherPublicKey.GetBigIntL(KDhKeyParameterXUid);
+	const TInteger& x = iPrivateKey->GetBigIntL(KDhKeyParameterxUid);
+
+	/*
+	 * both DH keys (ie our private and their public keys) must use the same N and G parameters
+	 */
+	if ((N != privateN) || (G != privateG))
+		{
+		User::Leave(KErrArgument);
+		}
+
+	/*
+	 * do the key agreement algo X ^ x mod N
+	 */
+	RInteger result = TInteger::ModularExponentiateL(X, x, N);
+	CleanupClosePushL(result);
+
+	/*
+	 * create the agreed key
+	 */
+	CCryptoParams* agreedKeyParameters = CCryptoParams::NewLC();
+	agreedKeyParameters->AddL(result, KSymmetricKeyParameterUid);
+	TKeyProperty agreedKeyProperties = {KDHAgreementUid, KCryptoPluginDhKeyAgreementUid,
+									KDHAgreedKeyUid, KNonEmbeddedKeyUid };
+	CKey* agreedKey = CKey::NewL(agreedKeyProperties, *agreedKeyParameters);
+
+	// cleanup result, agreedKeyParameters
+	CleanupStack::PopAndDestroy(2, &result);
+	return agreedKey;
+	}
+
+TUid CDHImpl::ImplementationUid() const
+	{
+	return KCryptoPluginDhKeyAgreementUid;
+	}
+
+CExtendedCharacteristics* CDHImpl::CreateExtendedCharacteristicsL()
+	{
+	// All Symbian software plug-ins have unlimited concurrency, cannot be
+	// reserved for exclusive use and are not CERTIFIED to be standards compliant.
+	return CExtendedCharacteristics::NewL(KMaxTInt, EFalse);
+	}
+
+const CExtendedCharacteristics* CDHImpl::GetExtendedCharacteristicsL()
+	{
+	return CDHImpl::CreateExtendedCharacteristicsL();
+	}
+