/*

* Copyright (c) 2007 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:    

*

*/

#ifndef C_CSTUNRELAYBINDINGIMPLEMENTATION_H

#define C_CSTUNRELAYBINDINGIMPLEMENTATION_H

// INCLUDES

#include <e32base.h>

#include <es_sock.h>

#include <in_sock.h>

#include "mstuntransactionobserver.h"

#include "cstuntimeruser.h"

#include "natfwbindingimplementationbase.h"

#include "stunturnclientlogs.h"

#include "natfwunsaftcprelaypacket.h"

// FORWARD DECLARATIONS

class MSTUNBindingObserver;

class MNcmConnectionMultiplexer;

// CLASS DECLARATION

/**

* Hides the implementation of STUN binding for the user of STUN client.

* @lib  natfwstunclient.dll

*/

class CSTUNRelayBindingImplementation : public CBindingImplementation

    {

    friend class ut_cstunrelaybindingimplementation;

    public:

    enum TRequestType

        {

        EUnknown                        = 0,

        ESendRequest                    = 1,

        EAllocateRequest                = 2,

        ETCPConnectRequest              = 3,

        ESetActiveDestinationRequest    = 4

        };

    public:  // Constructors and destructor

        /**

         * Creates a new instance of CSTUNRelayBindingImplementation.

         * Associates the local socket with the binding.

         * The public IP address is available when

         * MSTUNClientObserver::STUNBindingEventOccuredL gets called.

         *

         * @since   s60 3.2

         * @pre aClient.IsInitialized()

         * @param aBinding Associated binding interface

         * @param aClient An initialised STUN client

         * @param aSocket An opened socket that has the local port set.

         * @return a new instance, the ownership is transferred.

         */

        static CSTUNRelayBindingImplementation* NewL( CBinding& aBinding,

                                                 MSTUNBindingObserver& aClient,

                                                 RSocket& aSocket );

        static CSTUNRelayBindingImplementation* NewL( CBinding& aBinding,

                                         MSTUNBindingObserver& aClient,

                                         TUint aStreamId,

                                         TUint aConnection,

                                         MNcmConnectionMultiplexer* aMux );

        /**

         * Destructor.

         */

        ~CSTUNRelayBindingImplementation();

    public: // From CSTUNTimerUser

        void TimerExpiredL();

        void LeaveFromTimerExpired( TInt aError );

    public: // From MSTUNTransactionObserver

        void PublicAddressObtainedL( const TInetAddr& aAddress );

        void PublicAddressObtainedL( const TInetAddr& aReflexiveAddr,

                                     const TInetAddr& aRelayAddr );

        void TransactionError( TInt aError,

                               CNATFWUNSAFUnknownAttributesAttribute* aUnknownAttr );

        void TransactionEventOccurredL( TSTUNCallbackInfo::TFunction aEvent );

    public: // New functions

        /**

         * Refreshes the binding causing a new Binding Request to be sent

         * to the STUN relay server. The public IP address is available when 

         * MSTUNClientObserver gets called.

         *

         * @since   s60 3.2

         * @param   aRtoValue Retransmission timeout(=0 if default to be used)

         * @return  void

         */

        void AllocateRequestL( TUint aRtoValue );

        /**

         * Cancels a previously issued call to SendRequestL.

         *

         * @since   s60 3.2

         * @return  void

         */

        void CancelRequest();

        /**

         * Gets the socket used for obtaining the public address.

         *

         * @since    s60 3.2

         * @return socket

         */

        const RSocket& Socket() const;    

        /**

         * Checks whether the public address has a value set

         *

         * @since   s60 3.2

         * @return ETrue if the public address has been obtained, 

         *         otherwise EFalse. 

         */

        TBool AddressResolved() const;    

        /**

         * Gets the public address for this binding as seen in public network.

         *

         * @since   s60 3.2

         * @return public address

         */

        const TInetAddr& PublicAddr() const;

        /**

         * Returns the relayed address allocated for this binding

         * 

         * @since   s60 3.2

         * @return relay address

         */

        const TInetAddr& RelayAddr() const; 

        /**

         * Returns alternate server transport address.

         *

         * @since   s60 3.2

         * @return alternate server address

         */

        const TInetAddr& AlternateServerAddr() const;

        /**

         * Returns realm value from error response.

         *

         * @since   s60 3.2

         * @return realm from error response         

         */

        const HBufC8* RealmFromResponse() const;         

        /**

         * The client should call this function when it has received data

         * from the socket shared with this binding and 

         * the client cannot itself handle the data.

         *  

         * @since   s60 3.2

         * @param   aData data received

         * @param   aConsumed on return ETrue if the data was accepted,

         *          otherwise EFalse.

         * @param   aRemoteAddr remote address from remote address attribute

         * @return  Decoded data if not consumed and is not unsaf message,

         *          otherwise NULL.

         */

        HBufC8* HandleDataL( 

            const TDesC8& aData, TBool& aConsumed, TInetAddr& aRemoteAddr );

        /**

         * Returns the associated CSTUNClient instance.

         *

         * @since   s60 3.2

         * @return CSTUNClient, or NULL if the CSTUNClient has been deleted        

         */

        const CSTUNClient* STUNClient() const;

        /**

         * Get a STUN server address from STUN client

         *

         * @since   s60 3.2

         * @return  void

         */

        void GetServerAddressL();

        /**

         * Get a fresh a shared secret.

         *

         * @since   s60 3.2

         * @return  void     

         */

        void GetSharedSecretL();

        /**

         * Clears the pointer to CSTUNClient.

         *

         * @since   s60 3.2

         * @return  void

         * @post iClient == NULL        

         */

        void DetachClient();

        /**

         * Store the obtained public address and inform application.

         * Shouldn't be called in relay implementation.

         *

         * @since   s60 3.2

         * @param aPublicAddress Public address

         * @return  void

         */        

        void StoreAddressL( const TInetAddr& aPublicAddress );

        /**

         * Store the obtained addresses and inform application.

         *

         * @since   s60 3.2

         * @param   aReflexiveAddr  public IP address (server reflexive)

         * @param   aRelayAddr      public relay IP address

         * return   void

         */

        virtual void StoreAddressL( const TInetAddr& aReflexiveAddr,

                                    const TInetAddr& aRelayAddr );

        /**

         * Change the object's state.

         *

         * @since   s60 3.2

         * @param aNewState State to enter.

         * @return  void

         */

        void ChangeState( CSTUNBindingState& aNewState );

        /**

         * Binding encountered an error and enters terminated state. The function

         * MSTUNClientObserver::BindingErrorL is used to inform application.

         *

         * @since   s60 3.2

         * @pre aError != KErrNone

         * @param aError Error code

         * @return  void

         */

        void Terminate( TInt aError );        

        /**

         * Checks if this binding is waiting for shared secret.

         *

         * @since   s60 3.2

         * @return ETrue BInding is waiting shared secret, EFalse otherwise

         */

        TBool IsWaitingSharedSecret() const;

        /**

         * STUN client uses this function to give the username and password, that

         * the binding requested earlier with function

         * MSTUNBindingObserver::ObtainSharedSecretL.

         *

         * @since   s60 3.2

         * @pre aUsername and aPassword must either both have a descriptor that

         *      is not empty, or then both must have an empty descritor.

         * @param aUsername Username or an empty descriptor if the shared secret

         *                    is not used.

         * @param aPassword Password or an empty descriptor if the shared secret

         *                    is not used.

         * @return  void

         */

        void SharedSecretObtainedL( const TDesC8& aUsername,

                                    const TDesC8& aPassword );

        /**

         * Creates or updates a Binding Request message, using the given username

         * and password.

         *

         * @since   s60 3.2

         * @param aUsername Username

         * @param aPassword Password

         * @return  void

         */

        void CreateBindingRequestL( const TDesC8& aUsername,

                                    const TDesC8& aPassword );

        /**

         * Creates a transaction for sending Binding Request message

         *

         * @since   s60 3.2

         * @pre iRequest != NULL

         * @return  void     

         */                          

        void SendBindingRequestL();

        /**

         * Take actions based on the reason why transaction failed. For certain

         * errors, it is possible to send the Binding Request again.

         *

         * @since   s60 3.2

         * @pre aError != KErrNone

         * @param aError Error reason

         * @return ETrue Request can be retried

         *          EFalse Binding enters Terminated-state

         */

        TBool HandleTransactionError( TInt aError );

        /**

         * Forward the ICMP error to transaction for processing.

         *

         * @since   s60 3.2

         * @param aAddress Address where the ICMP error occurred

         * @return  void    

         */

        void IcmpError( const TInetAddr& aAddress );

        /**

         * Wait before retring to send a Binding Request

         *

         * @since   s60 3.2

         * @return  void  

         */

        void WaitBeforeRetrying();

        // From CBindingImplementation

        void SetICESpecificAttributes( const TICEAttributes& aAttributes );

        void SetActiveDestinationRequestL( const TInetAddr& aRemoteAddr, 

            TUint32& aTimerValue );

        void SendIndicationL( const TInetAddr& aRemoteAddr, 

            const TDesC8& aData, TBool aAddFingerprint );

        void ConnectRequestL( const TInetAddr& aRemoteAddr );

        TUint StreamId() const;

        TUint ConnectionId() const;

        const CBinding& Binding();

    private: // Constructors, for internal use

        CSTUNRelayBindingImplementation( CBinding& aBinding,        

                                    MSTUNBindingObserver& aClient,

                                    RSocket& aSocket );

        CSTUNRelayBindingImplementation( CBinding& aBinding,

                                    MSTUNBindingObserver& aStunClient, 

                                    TUint aStreamId,

                                    TUint aSubstreamId,

                                    MNcmConnectionMultiplexer* aMux );

        void ConstructL();

        CSTUNRelayBindingImplementation();

    private: // New functions, for internal use

        /**

         * Release the memory of the Binding Request related data. This data is

         * only needed for sending a Binding Request and receiving a response.

         *

         * @since   s60 3.2

         * @return  void

         */

        void FreeRequestData();

        /**

         * Return STUN client handle.

         *

         * @since   s60 3.2

         * @pre iClient != NULL

         * @return STUN client

         * @leave KErrNotFound If the STUN client has been deleted

         */

        MSTUNBindingObserver& ClientL() const;

        /**

         * Return the current username, or an empty descriptor if username

         * does not exist.

         *

         * @since   s60 3.2

         * @return Username

         */

        const TDesC8& Username() const;

        /**

         * Checks if the STUN server has requested client to use a shared secret.

         *

         * @since   s60 3.2

         * @return ETrue if STUN server requires the use of a shared secret

         *          EFalse otherwise

         */

        TBool IsSharedSecretRequired() const;

        /**

         * Decodes a byte stream and return the decoded UNSAF message.

         *

         * @since   s60 3.2

         * @param aData Byte stream to decode

         * @return Decoded message, ownership is transferred.

         *          NULL if the stream didn't contain an UNSAF message.

         */

        CNATFWUNSAFMessage* DecodeMessageL( const TDesC8& aData ) const;

        /**

         * Decodes a byte stream and returns a decoded TCP relay message.

         *

         * @since   s60 3.2

         * @param aData Byte stream to decode

         * @return A new instance of CNATFWUNSAFTcpRelayPacket.

         *         The ownership is transferred

         */

        CNATFWUNSAFTcpRelayPacket* DecodeTcpRelayMessageL( const 

            TDesC8& aData ) const;        

        /**

         * Checks message type.

         *

         * @since   s60 3.2

         * @param   aMsg pointer to message

         * @return  ETrue if message type is valid, else EFalse

         */

        TBool ValidateMsgType( CNATFWUNSAFMessage* aMsg ) const;

    private: // Data

        // Holds copy of remote address for connect request and  for set active

        // destination request

        TInetAddr iRemoteAddr;

        // Type of request

        TInt iRequestType;

        // Pointer to timer value

        TUint32* iTimerValue;

    private: // For testing purposes

#ifdef TEST_EUNIT

        friend class CSTUNClientTest;

        friend class CSTUNClientImplementationTest;

        friend class CSTUNBindingTest;

        friend class CSTUNBindingImplementationTest;

#endif

    };

#endif // CSTUNRELAYBINDINGIMPLEMENTATION_H

// End of File