omadrm/drmengine/agentv2/inc/DcfCache.h
changeset 0 95b198f216e5
child 12 8a03a285ab14
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/omadrm/drmengine/agentv2/inc/DcfCache.h	Thu Dec 17 08:52:27 2009 +0200
@@ -0,0 +1,266 @@
+/*
+* Copyright (c) 2002-2009 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:  Declaration of the DCF cache class
+*
+*/
+
+
+
+#ifndef DCFCACHE_H
+#define DCFCACHE_H
+
+//  INCLUDES
+#include <dcfcommon.h>
+#include <mode.h>
+#include <symmetric.h>
+#include <rijndael.h>
+
+// enables async reading
+#define ASYNC_READ
+
+// FORWARD DECLARATIONS
+
+class RFile;
+class RDRMRightsClient;
+class CDcfCommon;
+
+// CLASS DECLARATION
+
+/**
+ *  Cache for reading decrypted or plain data from a DCF file
+ *
+ *  @lib OmaDrmAgent.dll
+ *  @since Series 60 3.0
+ */
+
+class CDcfCache : public
+#ifdef ASYNC_READ
+    CActive
+#else
+    CBase
+#endif
+    {
+
+public:
+    // Constructors and destructor
+
+    /**
+     * Two-phased constructor.
+     */
+    static CDcfCache* NewL(
+        RDRMRightsClient& aRightsClient,
+        RFile& aFile,
+        CDcfCommon& aDcf,
+        TInt aPageSize = 2048,
+        TInt aPageCount = 32 );
+
+    /**
+     * Destructor.
+     */
+    virtual ~CDcfCache();
+
+public:
+    // New functions
+
+    /**
+     * Read data from the file via the cache. Depending on the decryption
+     * mode, the data is decrypted in the RightsServer or in the cache
+     * @since Series 60 3.0
+     * @param aPos Position from the start of the file where to read from
+     * @param aDes Descriptor holding the read data
+     * @param aLength Amount of data to read
+     * @return KErrNone if the data is read successfully
+     */
+    TInt Read(
+        TInt& aPos,
+        TDes8& aDes,
+        TInt aLength );
+
+    /**
+     * Set the decryption key to be used if decryption shall happen in the
+     * cache itself.
+     * @since Series 60 3.0
+     * @param aKey AES128 decryption key
+     * @return ?description
+     */
+    void SetKey(
+        const TDesC8& aKey );
+
+#ifdef ASYNC_READ
+
+    TInt Read(
+        TInt aPos,
+        TDes8& aDes,
+        TInt aLength,
+        TRequestStatus& aStatus );
+
+    void ReadCancel( TRequestStatus& aStatus );
+#endif
+
+protected:
+    // New functions
+
+    void CachedReadL(
+        TInt& aPos,
+        TDes8& aDes,
+        TInt aLength );
+
+    void UncachedReadL(
+        TInt& aPos,
+        TDes8& aDes,
+        TInt aLength );
+
+    /**
+     * Check if a file position is in the give cache page
+     * @since Series 60 3.0
+     * @param aPage Page to check
+     * @param aPosition Position to check
+     * @return ETrue if the position is in the cache page
+     */
+    TBool InPage( TInt aPage, TInt aPosition );
+
+    /**
+     * Return the index of a free cache page
+     * @since Series 60 3.0
+     * @return Index of a free cache page
+     */
+    TInt GetFreePage();
+
+    /**
+     * Read a page of plain data for a given file position into the cache
+     * @since Series 60 3.0
+     * @param aPage Page to read
+     * @param aPosition Position to read
+     */
+    void ReadPageL( TInt aPage, TInt aPosition );
+
+    /**
+     * Read a page of data for a given file position into the cache and
+     * decrypt it
+     * @since Series 60 3.0
+     * @param aPage Page to read
+     * @param aPosition Position to read
+     */
+    void ReadAndDecryptPageL( TInt aPage, TInt aPosition );
+
+    /**
+     * Copy data from a cache page into a descriptor
+     * @since Series 60 3.0
+     * @param aPage Page from which to read
+     * @param aDes Decscriptor where the data is stored
+     * @param aPosition Position in the file, updated with the new
+     *                  position after the data has been read
+     * @param aLength Amount of data to be read, updated with the actual
+     *                amount that was read
+     */
+    void CopyOut( TInt aPage, TDes8& aDes, TInt& aPosition, TInt& aLength );
+
+    /**
+     * Decrypt a memory buffer using either the stored key or the
+     * RightsServer.
+     * @since Series 60 3.0
+     * @param aIv AES CBC initialization vector
+     * @param aPtr Data to be decrypted
+     */
+    void DecryptL( const TDesC8& aIv, TPtr8& aPtr );
+
+#ifdef ASYNC_READ
+    void ReadAsyncL();
+#endif
+
+protected:
+    // Functions from base classes
+
+#ifdef ASYNC_READ
+
+    /**
+     * From CActive
+     * @since Series60 3.0
+     */
+    void RunL();
+
+    /**
+     * From CActive
+     * @since Series60 3.0
+     */
+    void DoCancel();
+
+    /**
+     * From CActive
+     */
+    TInt RunError( TInt aError );
+#endif
+
+private:
+
+    /**
+     * C++ default constructor.
+     */
+    CDcfCache(
+        RDRMRightsClient& aRightsClient,
+        RFile& aFile,
+        CDcfCommon& aDcf,
+        TInt aPageSize,
+        TInt aPageCount );
+
+    /**
+     * By default Symbian 2nd phase constructor is private.
+     */
+    void ConstructL();
+
+protected:
+    // Types and enumerations
+
+    enum TDecryptionMode
+        {
+        EServerSide,
+        EClientSide,
+        };
+
+#ifdef ASYNC_READ
+
+    enum TReadMode
+        {
+        ENonPosRead,
+        EPosRead,
+        };
+
+#endif
+protected:
+    // Data
+    RFile& iFile;
+    RDRMRightsClient& iRightsClient;
+    CDcfCommon& iDcf;
+    TInt iPageSize;
+    TInt iPageCount;
+    RPointerArray<TUint8> iPage;
+    RArray<TInt> iPageUsageCount;
+    RArray<TInt> iPagePosition;
+    TEncryptionMethod iEncryptionMethod;
+    TBuf8<KDCFKeySize> iKey;
+    TDecryptionMode iDecryptionMode;
+
+#ifdef ASYNC_READ
+    TRequestStatus* iAsyncStatus;
+    TInt iPos;
+    TDes8* iDes;
+    TInt iLength;
+    TReadMode iOperation;
+    TBool iAsyncReadingOngoing;
+    TInt iError;
+#endif
+    };
+
+#endif      // DCFCACHE_H
+// End of File