/*

* Copyright (c) 2005 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:    implementation

*

*/

#include "tsrtpstreaminstatenormal.h"

#include "msrtpstreamincontext.h"

#include "msrtpcryptohandlercontext.h"

#include "msrtpcryptohandlercontextrtp.h"

#include "msrtpcryptohandlercontextrtcp.h"

#include "srtputils.h"

// ----------------------------------------------------------------------------

// TSRTPStreamInStateNormal::TSRTPStreamInStateNormal

// ----------------------------------------------------------------------------

//

TSRTPStreamInStateNormal::TSRTPStreamInStateNormal(

    MSRTPStreamInContext& aStreamContext,

    MSRTPCryptoHandlerContextRTP& aCryptoHandlerRTPContext,

    MSRTPCryptoHandlerContextRTCP& aCryptoHandlerRTCPContext)

    : TSRTPStreamInStateBase(aStreamContext,

                            aCryptoHandlerRTPContext, 

                            aCryptoHandlerRTCPContext)

    {

    }

// ----------------------------------------------------------------------------

// TSRTPStreamInStateNormal::DoUnprotectSrtpL

// ----------------------------------------------------------------------------

//		

HBufC8* TSRTPStreamInStateNormal::DoUnprotectSrtpL(const TDesC8& aPacket)

    {

	SRTP_DEBUG_DETAIL( "TSRTPStreamInStateNormal::DoUnprotectSrtpL ENTRY" );

   	SRTP_DEBUG_TINT_VALUE( "Encrypted PacketLength is", aPacket.Length() );            

    // first initialize current encrypted RTP packet..

    iCryptoHandlerRTPContext.InitializeEncryptedPacketL(aPacket);    

    // Step 2 (in RFC 3711, section 3.3):

    // count the packet index i

    iCryptoHandlerRTPContext.CountReceiverPacketIndexL();

    // check MKI if it is used

    iCryptoHandlerRTPContext.CheckMasterKeyIdentifierL();

    // derive session keys..

    if (iCryptoHandlerRTPContext.MasterKeysUpdated())

        {

        iCryptoHandlerRTPContext.DeriveSessionKeysL();        

        }

    // do the replay protection 

    iCryptoHandlerRTPContext.ReplayProtectionL();

    // do the authentication (integrity check)

    iCryptoHandlerRTPContext.AuthenticateL();

     // decrypt..

    HBufC8* decryptedPacket = iCryptoHandlerRTPContext.DecryptL();

    // Step 7, conditional update s_l and ROC values..

    // (in RFC 3711, section 3.3):         

    iCryptoHandlerRTPContext.Update_s_l_and_RocL();

    iCryptoHandlerRTPContext.AddReplayIndex();

    ///Should check the next Packet Index and decide if need to be re-key

    SRTP_DEBUG_TINT_VALUE( "the decrypted packet Length is", decryptedPacket->Length());

    SRTP_DEBUG_DETAIL( "TSRTPStreamInStateNormal::DoUnprotectSrtpL EXIT" );

    return decryptedPacket;    

    }

// ----------------------------------------------------------------------------

// TSRTPStreamInStateNormal::DoUnprotectSrtcpL

// ----------------------------------------------------------------------------

//		

HBufC8* TSRTPStreamInStateNormal::DoUnprotectSrtcpL(const TDesC8& aPacket)

    {

    // first initialize current encrypted RTP packet..

    iCryptoHandlerRTCPContext.InitializeEncryptedPacketL(aPacket);    

  //(in RFC 3711, section 3.4):

    // count the packet index i

    iCryptoHandlerRTCPContext.ReceiverPacketIndexL();

    // check MKI if it is used

    iCryptoHandlerRTCPContext.CheckMasterKeyIdentifierL();

    // derive session keys..

    if (iCryptoHandlerRTCPContext.MasterKeysUpdated())

        {

        iCryptoHandlerRTCPContext.DeriveSessionKeysL();        

        }

    // do the replay protection 

    iCryptoHandlerRTCPContext.ReplayProtectionL();

    // do the authentication (integrity check)

    iCryptoHandlerRTCPContext.AuthenticateL();

     // decrypt..

    HBufC8* decryptedPacket = iCryptoHandlerRTCPContext.DecryptL();

    iCryptoHandlerRTCPContext.AddReplayIndex();  

    ///Should check the next Packet Index and decide if need to be re-key

    //Set updateKey needed and then lateron compared the key if the key is the same then ignore packet

    //implemented later

    // return decrypted RTCP packet

    return decryptedPacket;    

    }