1 /*

     2 * Copyright (c) 2002-2009 Nokia Corporation and/or its subsidiary(-ies).

     3 * All rights reserved.

     4 * This component and the accompanying materials are made available

     5 * under the terms of the License "Eclipse Public License v1.0"

     6 * which accompanies this distribution, and is available

     7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     8 *

     9 * Initial Contributors:

    10 * Nokia Corporation - initial contribution.

    11 *

    12 * Contributors:

    13 *

    14 * Description: 

    15 * ** IMPORTANT ** PublishedPartner API's in this file are published to 3rd party developers via the 

    16 * Symbian website. Changes to these API's should be treated as PublishedAll API changes and the Security TA should be consulted.

    17 * 3DES implementation

    18 *

    19 */

    20 

    21 

    22 /**

    23  @file 

    24  @publishedPartner

    25  @released 

    26 */

    27  

    28 #ifndef __3DES_H__

    29 #define __3DES_H__

    30 

    31 #include <des.h>

    32 

    33 /**

    34 * Abstract base class for triple-DES.

    35 *

    36 * Implements features common to triple-DES encryption and decryption.

    37 *

    38 */

    39 class C3DES : public CDES

    40 {

    41 public:

    42 	virtual void Transform(TDes8& aBlock);

    43 	virtual void Reset();

    44 	virtual TInt BlockSize() const;

    45 	virtual TInt KeySize() const;

    46 protected:

    47 	/** @internalAll */

    48 	C3DES();

    49 	virtual void ConstructL(const TDesC8& aKey);

    50 	/**

    51 	 * Initialises the three key schedule arrays from the specified key.

    52 	 * 

    53 	 * @param aKey	The key to be used for encryption. The key length

    54 	 *				must be K3DESKeySize = 24 bytes.

    55 	 */

    56 	virtual void DoSetKey(const TDesC8& aKey) = 0;

    57 	

    58 protected:

    59 	/** The second key schedule array */

    60 	TUint32 iK2[KDESScheduleSizeInWords];	//	= 32

    61 	/** The third key schedule array */

    62 	TUint32 iK3[KDESScheduleSizeInWords];

    63 };

    64 

    65 /**

    66 * Concrete class for triple-DES encryption.

    67 *

    68 */

    69 class C3DESEncryptor : public C3DES

    70 {

    71 public:

    72 	/**

    73 	* Creates an instance of this class.

    74 	*

    75 	* @param aKey	The key to be used for encryption. The key length

    76 	*				must be K3DESKeySize = 24 bytes.

    77 	* @return		A pointer to the new C3DESEncryptor object.

    78 	*

    79 	* @leave KErrKeyNotWeakEnough	If the key size is larger than that allowed by the

    80 	*								cipher strength restrictions of the crypto library.

    81 	*								See TCrypto::IsSymmetricWeakEnoughL()

    82 	*/

    83 	IMPORT_C static C3DESEncryptor* NewL(const TDesC8& aKey);

    84 

    85 	/**

    86 	* Creates an instance of this class and leaves it on the cleanup stack.

    87 	*

    88 	* @param aKey	The key to be used for encryption. The key length

    89 	*				must be K3DESKeySize = 24 bytes.

    90 	* @return		A pointer to the new C3DESEncryptor object.

    91 	*

    92 	* @leave KErrKeyNotWeakEnough 	If the key size is larger than that allowed by the

    93 	* 								cipher strength restrictions of the crypto library.

    94 	* 								See TCrypto::IsSymmetricWeakEnoughL()

    95 	*/

    96 	IMPORT_C static C3DESEncryptor* NewLC(const TDesC8& aKey);

    97 protected:

    98 	virtual void DoSetKey(const TDesC8& aKey);

    99 };

   100 

   101 /**

   102 * Concrete class for triple-DES decryption.

   103 *

   104 */

   105 class C3DESDecryptor : public C3DES

   106 {

   107 public:

   108 	/**

   109 	* Creates an instance of this class.

   110 	*

   111 	* @param aKey	The key to be used for decryption. The key length

   112 	*				must be K3DESKeySize = 24 bytes.

   113 	* @return		A pointer to the new C3DESDecryptor object.

   114 	*

   115 	* @leave KErrKeyNotWeakEnough	If the key size is larger than that allowed by the

   116 	*								cipher strength restrictions of the crypto library.

   117 	*								See TCrypto::IsSymmetricWeakEnoughL()

   118 	*/

   119 	IMPORT_C static C3DESDecryptor* NewL(const TDesC8& aKey);

   120 

   121 	/**

   122 	* Creates an instance of this class and leaves it on the cleanup stack.

   123 	*

   124 	* @param aKey	The key to be used for decryption. The key length

   125 	*				must be K3DESKeySize = 24 bytes.

   126 	* @return		A pointer to the new C3DESDecryptor object.

   127 	*

   128 	* @leave KErrKeyNotWeakEnough	If the key size is larger than that allowed by the

   129 	*								cipher strength restrictions of the crypto library.  

   130 	*								See TCrypto::IsSymmetricWeakEnoughL()

   131 	*/

   132 	IMPORT_C static C3DESDecryptor* NewLC(const TDesC8& aKey);

   133 protected:

   134 	virtual void DoSetKey(const TDesC8& aKey);

   135 };

   136 

   137 #endif	//	__3DES_H__