--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/crypto/weakcryptospi/source/asymmetric/dh.cpp	Fri Nov 13 10:07:38 2009 +0530
@@ -0,0 +1,107 @@
+/*
+* Copyright (c) 2003-2009 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 <asymmetric.h>
+#include <asymmetrickeys.h>
+#include "keys.h"
+#include "keyconverter.h"
+#include "cryptokeyagreementapi.h"
+#include <cryptospi/cryptospidef.h>
+
+using namespace CryptoSpi;
+
+CKeyAgreement* GetKeyAgreementCryptoInterfaceLC(TUid aKeyAgreementAlgoUid,
+	  CKey& aPrivateKey, CCryptoParams* aParams)
+	{
+	CKeyAgreement* keyAgreementImpl =  0;
+	CKeyAgreementFactory::CreateKeyAgreementL(keyAgreementImpl,
+												aKeyAgreementAlgoUid, aPrivateKey,
+												aParams);
+	CleanupStack::PushL(keyAgreementImpl);
+	return keyAgreementImpl;
+	}
+
+EXPORT_C CDH* CDH::NewL(const CDHPrivateKey& aPrivateKey)
+	{
+	CDH* self = CDH::NewLC(aPrivateKey);
+	CleanupStack::Pop(self);
+	return self;
+	}
+
+EXPORT_C CDH* CDH::NewLC(const CDHPrivateKey& aPrivateKey)
+	{
+	CDH* self = new (ELeave) CDH(aPrivateKey);
+	CleanupStack::PushL(self);
+	return self;
+	}
+
+EXPORT_C HBufC8* CDH::AgreeL(const CDHPublicKey& aPublicKey) const
+	{
+	/*
+	 * both DH keys (ie our private and their public keys) must use the same N and G parameters
+	 */
+	if ((aPublicKey.N() != iPrivateKey.N()) || (aPublicKey.G() != iPrivateKey.G()))
+		{
+		User::Leave(KErrArgument);
+		}
+
+	CKey* privateKey = KeyConverter::CreateKeyL(iPrivateKey);
+	CleanupStack::PushL(privateKey);
+
+	/*
+	 *  package the common parameters N and G into a crypto params array
+	 * we've already checked that both the private and public keys have the 
+	 * same N and G so we only need build this array once for both creating 
+	 * and calling the interface
+	 */
+	CCryptoParams* keyParameters = CCryptoParams::NewLC();
+	keyParameters->AddL(aPublicKey.N(), KDhKeyParameterNUid);
+	keyParameters->AddL(aPublicKey.G(), KDhKeyParameterGUid);
+
+	/* 
+	 * get a DH key agreement interface
+	 */
+	CKeyAgreement* keyAgreementImpl =  GetKeyAgreementCryptoInterfaceLC(KDHAgreementUid, *privateKey, keyParameters);
+
+	/* 
+	 * call the api to get a DH agreed key
+	 */
+	CKey* publicKey = KeyConverter::CreateKeyL(aPublicKey);
+	CleanupStack::PushL(publicKey);
+
+	CKey* agreedKey = keyAgreementImpl->AgreeL(*publicKey, keyParameters);
+	CleanupStack::PushL(agreedKey);
+
+	/*
+	 * extract the agreed key
+	 */
+	const TInteger& agreedKeyData = agreedKey->GetBigIntL(KSymmetricKeyParameterUid);
+	HBufC8 *agreedKeyToReturn = agreedKeyData.BufferLC();
+	CleanupStack::Pop(agreedKeyToReturn);
+
+	/* 
+	 * cleanup stack - it should contain privateKey, keyAgreementImpl, publicKey, keyParameters and agreedKey
+	 */
+	CleanupStack::PopAndDestroy(5, privateKey);
+
+	return agreedKeyToReturn;
+	}
+
+EXPORT_C CDH::CDH(const CDHPrivateKey& aPrivateKey) : iPrivateKey(aPrivateKey)
+	{
+	}