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 

    24 /**

    25  @file 

    26  @internalAll

    27 */

    28  

    29 #ifndef __3DES_H__

    30 #define __3DES_H__

    31 

    32 #include "des.h"

    33 

    34 /**

    35 * Abstract base class for triple-DES.

    36 *

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

    38 *

    39 * @publishedPartner

    40 * @released 

    41 */

    42 class C3DES : public CDES

    43 {

    44 public:

    45 	virtual void Transform(TDes8& aBlock);

    46 	virtual void Reset();

    47 	virtual TInt BlockSize() const;

    48 	virtual TInt KeySize() const;

    49 protected:

    50 	/** @internalAll */

    51 	C3DES();

    52 	virtual void ConstructL(const TDesC8& aKey);

    53 	/**

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

    55 	 * 

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

    57 	 *				must be K3DESKeySize = 24 bytes.

    58 	 */

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

    60 	

    61 protected:

    62 	/** The second key schedule array */

    63 	TUint32 iK2[KDESScheduleSizeInWords];	//	= 32

    64 	/** The third key schedule array */

    65 	TUint32 iK3[KDESScheduleSizeInWords];

    66 };

    67 

    68 /**

    69 * Concrete class for triple-DES encryption.

    70 *

    71 * @publishedPartner

    72 * @released 

    73 */

    74 class C3DESEncryptor : public C3DES

    75 {

    76 public:

    77 	/**

    78 	* Creates an instance of this class.

    79 	*

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

    81 	*				must be K3DESKeySize = 24 bytes.

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

    83 	*

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

    85 	*								cipher strength restrictions of the crypto library.

    86 	*								See TCrypto::IsSymmetricWeakEnoughL()

    87 	*/

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

    89 

    90 	/**

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

    92 	*

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

    94 	*				must be K3DESKeySize = 24 bytes.

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

    96 	*

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

    98 	* 								cipher strength restrictions of the crypto library.

    99 	* 								See TCrypto::IsSymmetricWeakEnoughL()

   100 	*/

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

   102 protected:

   103 	virtual void DoSetKey(const TDesC8& aKey);

   104 };

   105 

   106 /**

   107 * Concrete class for triple-DES decryption.

   108 *

   109 * @publishedPartner

   110 * @released 

   111 */

   112 class C3DESDecryptor : public C3DES

   113 {

   114 public:

   115 	/**

   116 	* Creates an instance of this class.

   117 	*

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

   119 	*				must be K3DESKeySize = 24 bytes.

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

   121 	*

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

   123 	*								cipher strength restrictions of the crypto library.

   124 	*								See TCrypto::IsSymmetricWeakEnoughL()

   125 	*/

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

   127 

   128 	/**

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

   130 	*

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

   132 	*				must be K3DESKeySize = 24 bytes.

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

   134 	*

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

   136 	*								cipher strength restrictions of the crypto library.  

   137 	*								See TCrypto::IsSymmetricWeakEnoughL()

   138 	*/

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

   140 protected:

   141 	virtual void DoSetKey(const TDesC8& aKey);

   142 };

   143 

   144 #endif	//	__3DES_H__