/*

* 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:    General SRTP packet class (RTP/SRTP/RTCP/SRTCP)

*

*/

#ifndef __SRTP_PACKET_H__

#define __SRTP_PACKET_H__

// INCLUDES

#include <in_sock.h>

// FORWARD DECLARATIONS

class CSRTPCryptoHandler;

/**

* Contains general packet routines

*/

class CSRTPPacket : public CBase

    {

    public:

        /**

        * Get payload entry. Here the "payload" denotes the

        * encrypted portion (incl. RTCP/SRTCP).

        * @return pointer reference to the encrypted portion. 

        */        

        TPtrC8 Payload();    

        /**

        * Get header length.

        * @return length of the header.

        */        

        TUint HeaderLength();

        /**

        * Get payload length (== length of the encrypted portion).

        * @return length of the payload.

        */        

        TUint PayloadLength();

        /**

        * Get header and encrypted portion, excluding possible 

        * MKI and authentication tag.

        * @return header and encrypted portion.

        */                            

        TPtrC8 HeaderAndPayload();      

        /**

        * Get the authentication portion for recv stream data

        * For RTP this gets header and payload as authentication portion

        * For RTCP it gets payload + SRTCP index

        * @param rtcp if it is rtcp packet

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

        * @return payload concatenated with ROC.

        */                            

        HBufC8* Get_Concatenated_MDataL(TBool rtcp); 

        /**

        * Create a new packet by allocating given size

        * and by copying header and given payload.

        * This can be any packet: RTP/SRTP/RTCP/SRTCP

        * @param aPacketSize  new packet size.

        * @param aPayloadPtr   pointer to the payload to be copied.

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

        * @return new packet with header and payload.

        */                            

        HBufC8* CopyHeaderAndPayloadL(TUint aPacketSize,

                                       TUint8* aPayloadPtr);

        ~CSRTPPacket();                

        /**

        * virtual function for creating decrypted packet,

        * implemented in CSRTPPacketSRTP/CSRTPPacketSRTCP,

        */                            

        virtual HBufC8* CreateDecryptedPacketL(TUint8* aDecryptedPayloadPtr);

        /**

        * virtual function for creating encrypted packet,

        * implemented in CSRTPPacketRTP/CSRTPPacketRTCP,

        */                            

        virtual HBufC8* CreateEncryptedPacketL(TUint8* aEncryptedPayloadPtr);        

        /**

        * virtual function for getting the authentication tag,

        * implemented in CSRTPPacketSRTP/CSRTPPacketSRTCP

        */                                    

        virtual TPtrC8 AuthenticationTag();

        /**

        * virtual function for getting the sequence number,

        * implemented in CSRTPPacketRTP

        */                                    

        virtual TUint16 SequenceNumber(); 

        /**

        * virtual function for setting the packet index value,

        * implemented in CSRTPPacketRTP

        */                                    

        virtual void SetPacketIndex(TUint64 aPacketIndex);

        /**

        * virtual function for getting the MKI value,

        * implemented in CSRTPPacketSRTP/CSRTPPacketSRTCP

        */                                            

        virtual TPtrC8 MasterKeyIdentifier();

        /**

        * virtual function for counting the sender-side packet index

        * implemented in CSRTPPacketRTP

        */                                            

        virtual void CountSenderPacketIndex(); 

        /**

        * virtual function for getting the packet index value,

        * implemented in CSRTPPacketRTP

        */                                    

        virtual TUint64 PacketIndex();        

		/**

        * Get Sender Roll-Over Counter from RTP/SRTP packets defined by RCC mode

        * @return 32 bit unsigned integer 

        */                              

        virtual TUint32 GetSenderROC(); 

    protected: //methods

        /*

        * Update header length member

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

        * @return void

        */

        void UpdatePayloadLengthL();

        /*

        * Update payload member in this class

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

        * @return void

        */

        void UpdatePayload();        

        /*

        * Read sequence number. 

        * @return 16 bit sequence number.

        */

        TUint16 GetSequenceNumber();

        void ConstructL();

        CSRTPPacket (const TDesC8& aPacket,

                      CSRTPCryptoHandler& aHandler);

    protected: //data

        TPtrC8                        iPacket;  // packet

    	const TUint8                  *iDataP;  // pointer to packet

        CSRTPCryptoHandler&           iHandler; // crypto handler

        TPtrC8                        iPayload; // payload (encrypted portion)

        TUint                         iHeaderLength; // header length

        TUint                         iPayloadLength; // payload length

	private:

    #ifdef EUNIT_TESTING

        friend class UT_CSRTPCryptoHandlerSRTP;

    #endif 

    };

#endif // __SRTP_PACKET_H__