/*

* Copyright (c) 2006-2009 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:  DRM Utility

*

*/

// INCLUDE FILES

#include <Oma2Dcf.h>

#include <drmagents.h>

#include <drmutility.h>

#include <centralrepository.h>

#include <UTF.h>

#include "Oma1Dcf.h"

#include "DrmUtilityInternalcrkeys.h"      // Cenrep extension for OmaBased

// CONSTANTS

_LIT8( KASFHeaderObject, "75B22630668E11CFA6D900AA0062CE6C" );

_LIT8( KWrmHeader, "W\0R\0M\0H\0E\0A\0D\0E\0R\0" );

const TInt KMinContentLength( 16 );

const TInt KOma2EncryptionFieldOffset( 8 );

const TInt KOmaHeaderLength( 512 );

// This constant is for OMA1 case in which a buffer of 35-40

// bytes is needed to recognize the mime type.

const TInt KMinContentLengthOma1Based( 40 );

const TInt KWMHeaderObjectLength( 8 );

const TInt KWMTopLevelHeaderObjectLength( 30 );

const TInt KMaxWMHeaderLength( ( KMaxTInt32 / 2 ) - 1 );

const TInt KCenRepDataLength( 50 );

// ============================ LOCAL FUNCTIONS ================================

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

// FormatGUID

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

//

LOCAL_C void FormatGUID( TDes8 &aGUID )

    {

    TBuf8<16> copyGUID( aGUID );

    TInt i( 0 );

    for ( i = 0; i < 4; i++ )

        {

        copyGUID[i] = aGUID[3-i];

        }

    for ( i = 4; i < 6; i++ )

        {

        copyGUID[i] = aGUID[9 - i];

        }

    for ( i = 6; i < 8; i++ )

        {

        copyGUID[i] = aGUID[13 - i];

        }

    for ( i = 8; i < 16 ; i++) 

        {

        copyGUID[i] = aGUID[i];

        }

    aGUID.Delete( 0, 32 );

    for ( i = 0; i < 16; i++ )

        {

        aGUID.AppendNumFixedWidthUC( copyGUID[i], EHex, 2 );

        }

    }

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

// ConvertToInt64

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

//

LOCAL_C TInt64 ConvertToInt64( TDesC8& aDes )

    {

    TInt64 num( 0 );

    TInt i( 0 );

    for ( i = 7 ; i >= 0; i-- )

        {

        num <<= 8;

        num |= aDes[i];

        }

    return num;

    }

// ============================ MEMBER FUNCTIONS ===============================

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

// Default constructor

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

//  

DRM::CDrmUtility::CDrmUtility()

    {

    }

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

// Destructor

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

//  

DRM::CDrmUtility::~CDrmUtility()

    {

    delete iOmaBasedAgentName;

    delete iOmaBasedMimeType;

    }

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

// CDrmUtility::NewLC

// First phase constructor

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

//  

EXPORT_C DRM::CDrmUtility* DRM::CDrmUtility::NewLC()

    {

    DRM::CDrmUtility* self( new( ELeave ) CDrmUtility );

    CleanupStack::PushL( self );

    self->ConstructL();

    return self;

    }

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

// CDrmUtility::NewL

// First phase constructor

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

//  

EXPORT_C DRM::CDrmUtility* DRM::CDrmUtility::NewL()

    {

    DRM::CDrmUtility* self( NewLC() );

    CleanupStack::Pop();

    return self;

    }

void DRM::CDrmUtility::ConstructL()

    {

    TInt err( KErrNone );

     TRAP(err, FetchOmaBasedInfoL() );

     if( err)

         {

         if( iOmaBasedAgentName )

             {

             delete iOmaBasedAgentName;

             }

         iOmaBasedAgentName = NULL;

         if( iOmaBasedMimeType )

             {

             delete iOmaBasedMimeType;

             }

         iOmaBasedMimeType = NULL;

         }   

    }

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

// CDrmUtility::FetchOmaBasedInfoL

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

//

void DRM::CDrmUtility::FetchOmaBasedInfoL()

    {

    TInt err = KErrNone;

    CRepository* repository( NULL );

    RBuf bOmaBasedAgentName;

    RBuf bOmaBasedMimeType;

    CleanupClosePushL(bOmaBasedAgentName);

    CleanupClosePushL(bOmaBasedMimeType);

    bOmaBasedAgentName.CreateL( KCenRepDataLength );

    bOmaBasedMimeType.CreateL( KCenRepDataLength );

    TRAP( err, repository = CRepository::NewL( KCRUidOmaBased ) );

    if ( !err )

        {

        CleanupStack::PushL( repository );

        err = repository->Get( KDrmOmaBasedName, bOmaBasedAgentName );

        if( !err )

            {

            iOmaBasedAgentName = bOmaBasedAgentName.AllocL(); 

            }

        err = repository->Get( KOmaBasedMimeType, bOmaBasedMimeType );

        if( !err )

            {

            iOmaBasedMimeType = CnvUtfConverter::ConvertFromUnicodeToUtf8L( bOmaBasedMimeType );

            }

        CleanupStack::PopAndDestroy( repository );

        }

    CleanupStack::PopAndDestroy(2);

    User::LeaveIfError( err );

    }

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

// CDrmUtility::GetDrmInfoL

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

//  

EXPORT_C TBool DRM::CDrmUtility::GetDrmInfoL( 

    RFile& aFileHandle,

    TPtrC& aAgent,

    DRM::TDrmProtectionStatus& aProtected ) const

    {

    TInt r( KErrNone );

    HBufC8* buffer( NULL );

    TInt pos( 0 );

    RFile file;

    TBuf8< 32 > header;

    TInt64 headerSize( 0 );

    TBool isDrmFile( EFalse );

    TPtr8 headerPtr( NULL, 0 );

    aProtected = DRM::EUUnprotected;

    aAgent.Set( KNullDesC );

    CheckFileHandleL( aFileHandle );

    User::LeaveIfError( file.Duplicate( aFileHandle ) );

    CleanupClosePushL( file );

    User::LeaveIfError( file.Seek( ESeekStart, pos ) );

    // Check if the file is an ASF file

    // To be Checked on runtime wether WM DRM is supporeted or not

    User::LeaveIfError( file.Read( 0, header, KMinContentLength ) );

    if ( header.Length() < KMinContentLength )

        {

        User::Leave( KErrArgument ); 

        }    

    FormatGUID( header );

    if ( header == KASFHeaderObject )

        {

        // It's ASF, check still whether it's WM DRM protected or not

        file.Read( header, KWMHeaderObjectLength );

        headerSize = ConvertToInt64( header );

        if( headerSize <= KWMTopLevelHeaderObjectLength || 

            headerSize > KMaxWMHeaderLength )

            {

            User::Leave( KErrArgument );

            }

        buffer = HBufC8::NewLC( headerSize );

        headerPtr.Set( buffer->Des() ); 

        User::LeaveIfError( file.Read( headerPtr, 

                headerSize - ( KMinContentLength + KWMHeaderObjectLength ) ) );

        r = headerPtr.Find( KWrmHeader );

        if ( r == KErrNotFound ) 

            {

            aProtected = DRM::EUUnprotected;

            }

        else

            {

            isDrmFile = ETrue;

            aProtected = DRM::EUProtected;

            aAgent.Set( DRM::KDrmWMAgentName );                            

            }

        CleanupStack::PopAndDestroy( buffer ); // buffer    

        }

    else

        {

        // Check whether it's OMA DRM protected or not

        buffer = HBufC8::NewLC( KOmaHeaderLength );

        headerPtr.Set( buffer->Des() );

        User::LeaveIfError( file.Read( 0, headerPtr ));

        if ( COma1Dcf::IsValidDcf( headerPtr ) )

            {

            isDrmFile = ETrue;

            aProtected = DRM::EUProtected;                             

            aAgent.Set( DRM::KDrmOmaAgentName );                

            }

        else if ( COma2Dcf::IsValidDcf( headerPtr ) )

            {

            isDrmFile = ETrue;

            _LIT8( KCommonHeadersBox, "ohdr" );

            pos = headerPtr.Find( KCommonHeadersBox );

            // If no box can be found or if there isn't enough data

            // set protection as unknown

            if( pos == KErrNotFound || 

                headerPtr.Length() < pos + KOma2EncryptionFieldOffset )

                {

                aProtected = DRM::EUUnknown;

                }

            // If encryption field is 0, then content isn't protected

            else if ( !headerPtr[pos + KOma2EncryptionFieldOffset] )

                {

                aProtected = DRM::EUUnprotected;

                }

            else

                {

                aProtected = DRM::EUProtected;

                }                  

            aAgent.Set( DRM::KDrmOmaAgentName );                

            }   

        else if ( (buffer->Des())[0] == 1)

            {

            // set the mimetype from the buffer which is in the beginning

            // starting from byte 3 with the length specified at position 2		

            TPtrC8 mimeType( buffer->Des().Mid(3, (buffer->Des())[1]) );

            if( !mimeType.CompareF( *iOmaBasedMimeType ) ) 

                {	

                aAgent.Set( *DRM::CDrmUtility::iOmaBasedAgentName );

                isDrmFile = ETrue;

                }

            }

        CleanupStack::PopAndDestroy( buffer );

        }  

    CleanupStack::PopAndDestroy( &file ); // file

    return isDrmFile;

    }  

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

// CDrmUtility::GetDrmInfoL

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

//  

EXPORT_C TBool DRM::CDrmUtility::GetDrmInfoL( 

    const TDesC8& aContent,

    TPtrC& aAgent,

    DRM::TDrmProtectionStatus& aProtected ) const

    {

    TInt r( KErrNone );

    RFile file;

    TPtr8 asfPtr( NULL, 0 );

    TBuf8< 32 > asfGuidHex;

    TBool isDrmFile( EFalse );

    aProtected = DRM::EUUnprotected;

    aAgent.Set( KNullDesC );

    if ( aContent.Length() < KMinContentLength )

        {

        User::Leave( KErrArgument );   

        }

    // Check if the file is an ASF file

    asfPtr.Set( 

        const_cast<TUint8*>( asfGuidHex.Ptr() ), 0, KMinContentLength * 2 );

    asfPtr.Copy( aContent.Left( KMinContentLength ) );    

    FormatGUID( asfPtr );

    if ( asfPtr == KASFHeaderObject )

        {

        // It's ASF, check still whether it's WM DRM protected or not

        r = aContent.Find( KWrmHeader );

        if ( r == KErrNotFound ) 

            {

            aProtected = DRM::EUUnprotected;   

            }

        else

            {

            isDrmFile = ETrue;

            aProtected = DRM::EUProtected;                               

            aAgent.Set( DRM::KDrmWMAgentName ); 

            }   

        }

    else

        {

        // Check whether it's OMA DRM protected or not.

        if ( ( aContent.Length() >= KMinContentLengthOma1Based ) && 

            ( COma1Dcf::IsValidDcf( aContent ) ) )

            {

            isDrmFile = ETrue;

            aProtected = DRM::EUProtected;                          

            aAgent.Set( DRM::KDrmOmaAgentName );

            }

        else if ( COma2Dcf::IsValidDcf( aContent ) )

            {

            isDrmFile = ETrue;

            _LIT8( KCommonHeadersBox, "ohdr" );

            TInt pos( aContent.Find( KCommonHeadersBox ) );

            // If no box can be found or if there isn't enough data

            // set protection as unknown

            if ( pos == KErrNotFound || 

                 aContent.Length() < pos + KOma2EncryptionFieldOffset )

                {

                aProtected = DRM::EUUnknown;

                }

            // If encryption field is 0, then content isn't protected    

            else if ( !aContent[pos + KOma2EncryptionFieldOffset] )

                {

                aProtected = DRM::EUUnprotected;    

                }

            else

                {

                aProtected = DRM::EUProtected;    

                }                               

            aAgent.Set( DRM::KDrmOmaAgentName );            

            }

        else if ( (aContent)[0] == 1)

            {

            // set the mimetype from the buffer which is in the beginning

            // starting from byte 3 with the length specified at position 2     

            TPtrC8 mimeType( aContent.Mid(3, (aContent)[1]) );

            if( !mimeType.CompareF( *iOmaBasedMimeType ) )

                {   

                aAgent.Set( *DRM::CDrmUtility::iOmaBasedAgentName );

                isDrmFile = ETrue;

                aProtected = DRM::EUProtected;

                }

            }

        }

    return isDrmFile;

    }      

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

// CDrmUtility::IsProtectedL

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

//  

EXPORT_C TBool DRM::CDrmUtility::IsProtectedL( RFile& aFileHandle ) const

    {

    DRM::TDrmProtectionStatus protection( DRM::EUUnknown );

    TPtrC agent( KNullDesC );

    TBool isDrmFile( EFalse );

    TBool isProtected( EFalse );

    isDrmFile = GetDrmInfoL( aFileHandle, agent, protection );

    if ( isDrmFile && protection == DRM::EUProtected )

        {

        isProtected = ETrue;

        }

    return isProtected;

    }

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

// CDrmUtility::IsProtectedL

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

//  

EXPORT_C TBool DRM::CDrmUtility::IsProtectedL( const TDesC8& aContent ) const

    {

    DRM::TDrmProtectionStatus protection( DRM::EUUnknown );

    TPtrC agent( KNullDesC );

    TBool isDrmFile( EFalse );

    TBool isProtected( EFalse );

    isDrmFile = GetDrmInfoL( aContent, agent, protection );

    if( isDrmFile && protection == DRM::EUProtected )

        {

        isProtected = ETrue;

        }

    return isProtected;

    }

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

// CDrmUtility::GetAgentL

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

//  

EXPORT_C TBool DRM::CDrmUtility::GetAgentL( 

    RFile& aFileHandle,

    TPtrC& aAgent ) const

    {

    DRM::TDrmProtectionStatus protection( DRM::EUUnknown );

    TBool isDrmFile( EFalse );

    isDrmFile = GetDrmInfoL( aFileHandle, aAgent, protection );

    return isDrmFile;

    }

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

// CDrmUtility::GetAgentL

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

//  

EXPORT_C TBool DRM::CDrmUtility::GetAgentL( 

    const TDesC8& aContent,

    TPtrC& aAgent ) const

    {

    DRM::TDrmProtectionStatus protection( DRM::EUUnknown );

    TBool isDrmFile( EFalse );

    isDrmFile = GetDrmInfoL( aContent, aAgent, protection );

    return isDrmFile;

    }

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

// CDrmUtility::CheckFileHandlerL

// Checks whether given filehandle is valid if not leaves with KErrArgument

// (other items were commented in a header).

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

// 

EXPORT_C void DRM::CDrmUtility::CheckFileHandleL( RFile& aFileHandle ) const

    {

    if ( !aFileHandle.SubSessionHandle() )

        {

        User::Leave( KErrBadHandle );

        }

    }

//  End of File