/*

* Copyright (c) 2004 Nokia Corporation and/or its subsidiary(-ies).

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of "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:    Contains SRTP master salt class.

*

*/

#ifndef __SRTP_MASTER_SALT_H__

#define __SRTP_MASTER_SALT_H__

// INCLUDES

#include <e32def.h>

#include <e32des8.h>

#include "srtpdef.h"

/**

* Contains a salt used in encryption and decryption.

*/

class CSRTPMasterSalt : public CBase

    {

    public: // constructor

        /**

        * Two-phased constructor.

        * CSRTPCryptoContext takes the ownership of MasterKey and MasterSalt 

        * @param aKey  The master salt value.

        * @param aN_S  The length of the session salt

        * @leave KErrNone if success, system-wide error code otherwise

        */

        IMPORT_C static CSRTPMasterSalt* NewL( const TDesC8& aKey, 

                        TUint aN_S = KSRTPDefSessionSaltingKeyLength );

        /**

        * Two-phased constructor.

        * CSRTPCryptoContext takes the ownership of MasterKey and MasterSalt 

        * @param aKey  The master salt value.

        * @param aN_S  The length of the session salt

        * @leave KErrNone if success, system-wide error code otherwise

        */

        IMPORT_C static CSRTPMasterSalt* NewLC( const TDesC8& aKey, 

                        TUint aN_S = KSRTPDefSessionSaltingKeyLength );

        /**

        * Destructor

        */

        ~CSRTPMasterSalt();                

        /*

		* Gets master salt

        * @return master salt

        */                                

        IMPORT_C  const TDesC8& MasterSalt() const;

        /*

		* Gets length of the session salt

        * @return length of the session salt

        */                                

        IMPORT_C  TUint SaltLength() const;

        /*

		* Check the validity of the whole CSRTPMasterSalt

        * @return validity of this CSRTPMasterSalt

        */

        IMPORT_C  TBool Valid() const;                 

    private: // methods

        CSRTPMasterSalt( TUint aN_S );

        void ConstructL( const TDesC8& aKey );

        /* assignment operator */

         const CSRTPMasterSalt& operator=(const CSRTPMasterSalt& aSalt);  

    private: // data

        /**

        * The master salt value.

        * The length of the salt is determined by the Size() function.

        */

        HBufC8 *iKey;

        /**

        * The length of the session salt

        */

        const TUint iN_S;

    friend class CSRTPCryptoContext;

	#ifdef EUNIT_TESTING

        friend class UT_CSRTPMasterSalt;

    #endif         

    };

#endif // __SRTP_MASTER_SALT_H__