SHOW Signed

net.rim.device.api.crypto
Class RC5EncryptorEngine

java.lang.Object
  |
  +--net.rim.device.api.crypto.RC5EncryptorEngine

All Implemented Interfaces:

BlockEncryptorEngine, SymmetricKeyEncryptorEngine

public final class RC5EncryptorEngine

extends Object

implements SymmetricKeyEncryptorEngine

The RC5EncryptorEngine class implements the encryption functionality of the RC5 block cipher.

We implemented RC5 as per RFC 2040.

Note: The RIM implementation has some limitations compared to the specified algorithm itself. The RIM implementation only supports a block size of 64. As well, the RIM implementation only allows 16 rounds or less. It does not allow more than 16 rounds. However, the key size is allowed to range from its minimum to maximum (0 to 2040 bits).

Category:

Signed: This element is only accessible by signed clients. If you intend to use this element, please contact RIM to establish the necessary agreements that will allow you to have your COD files signed. Signing is only required for use on the device, development under the JDE can occur without signing the CODs.

Since:

JDE 3.6.0

Constructor Summary

	RC5EncryptorEngine(RC5Key key) Creates an RC5EncryptorEngine object given an RC5 key.
	RC5EncryptorEngine(RC5Key key, int blockLength) Creates an RC5EncryptorEngine object given an RC5 key.
	RC5EncryptorEngine(RC5Key key, int blockLength, int numberOfRounds) Creates a RC5EncryptorEngine object given an RC5 key, the block length, and the number of rounds.

Method Summary

	void	encrypt(byte[] plaintext, int plaintextOffset, byte[] ciphertext, int ciphertextOffset) Encrypts a block of the given plaintext into a block of ciphertext.
	String	getAlgorithm() Returns the name of the algorithm used, eg "RC5_64_64_16" ("RC5_" + keyBitLength + "_" + blockBitLength + "_" + numberOfRounds).
	int	getBlockLength() Returns the block length of the engine in bytes.
	int	getKeyLength() Returns the length of the engine's key in bytes.
	int	getNumberOfRounds() Returns the number of rounds used.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

RC5EncryptorEngine

public RC5EncryptorEngine(RC5Key key)
                   throws CryptoTokenException,
                          CryptoUnsupportedOperationException

Creates an RC5EncryptorEngine object given an RC5 key. Block length is set to 8 bytes, and the cipher is computed for 16 rounds.

Parameters:

key - The RC5 key to use with the engine.

Throws:

CryptoTokenException - Thrown when an error occurs with a crypto token or the crypto token is invalid.

CryptoUnsupportedOperationException - Thrown when a call is made to an unsupported operation.

Since:

JDE 3.6.0

Category:

Signed: This element is only accessible by signed clients. If you intend to use this element, please contact RIM to establish the necessary agreements that will allow you to have your COD files signed. Signing is only required for use on the device, development under the JDE can occur without signing the CODs.

RC5EncryptorEngine

public RC5EncryptorEngine(RC5Key key,
                          int blockLength)
                   throws CryptoTokenException,
                          CryptoUnsupportedOperationException

Creates an RC5EncryptorEngine object given an RC5 key. The cipher is computed for 16 rounds.

Parameters:

key - The RC5 key to use with the engine.

blockLength - The block length of the cipher.

Throws:

CryptoTokenException - Thrown when an error occurs with a crypto token or the crypto token is invalid.

CryptoUnsupportedOperationException - Thrown when a call is made to an unsupported operation.

Since:

JDE 3.6.0

Category:

Signed: This element is only accessible by signed clients. If you intend to use this element, please contact RIM to establish the necessary agreements that will allow you to have your COD files signed. Signing is only required for use on the device, development under the JDE can occur without signing the CODs.

RC5EncryptorEngine

public RC5EncryptorEngine(RC5Key key,
                          int blockLength,
                          int numberOfRounds)
                   throws CryptoTokenException,
                          CryptoUnsupportedOperationException

Creates a RC5EncryptorEngine object given an RC5 key, the block length, and the number of rounds.

Parameters:

key - The RC5 key to use with the engine.

blockLength - The cipher block length in bytes (8 or 16).

numberOfRounds - The number of rounds (0 to 255).

Throws:

CryptoTokenException - Thrown when an error occurs with a crypto token or the crypto token is invalid.

CryptoUnsupportedOperationException - Thrown when a call is made to an unsupported operation.

Since:

JDE 3.6.0

Category:

Signed: This element is only accessible by signed clients. If you intend to use this element, please contact RIM to establish the necessary agreements that will allow you to have your COD files signed. Signing is only required for use on the device, development under the JDE can occur without signing the CODs.

Method Detail

getAlgorithm

public String getAlgorithm()

Returns the name of the algorithm used, eg "RC5_64_64_16" ("RC5_" + keyBitLength + "_" + blockBitLength + "_" + numberOfRounds).

Specified by:

getAlgorithm in interface BlockEncryptorEngine

Returns:

A String that represents the name of the algorithm (including the appended key length and block length).

Since:

JDE 3.6.0

Category:

Signed: This element is only accessible by signed clients. If you intend to use this element, please contact RIM to establish the necessary agreements that will allow you to have your COD files signed. Signing is only required for use on the device, development under the JDE can occur without signing the CODs.

getBlockLength

public int getBlockLength()

Description copied from interface: BlockEncryptorEngine

Returns the block length of the engine in bytes.

Specified by:

getBlockLength in interface BlockEncryptorEngine

Since:

JDE 3.6.0

Category:

Signed: This element is only accessible by signed clients. If you intend to use this element, please contact RIM to establish the necessary agreements that will allow you to have your COD files signed. Signing is only required for use on the device, development under the JDE can occur without signing the CODs.

getKeyLength

public int getKeyLength()

Returns the length of the engine's key in bytes.

Returns:

An integer that represents the length of the key.

Since:

JDE 3.6.0

Category:

Signed: This element is only accessible by signed clients. If you intend to use this element, please contact RIM to establish the necessary agreements that will allow you to have your COD files signed. Signing is only required for use on the device, development under the JDE can occur without signing the CODs.

getNumberOfRounds

public int getNumberOfRounds()

Returns the number of rounds used.

The number of rounds specifies the number of times the plaintext has been "scrambled". In theory, the encryption scheme becomes more secure as the number of rounds is increased.

Returns:

An integer that represents the number of rounds.

Since:

JDE 3.6.0

Category:

Signed: This element is only accessible by signed clients. If you intend to use this element, please contact RIM to establish the necessary agreements that will allow you to have your COD files signed. Signing is only required for use on the device, development under the JDE can occur without signing the CODs.

encrypt

public void encrypt(byte[] plaintext,
                    int plaintextOffset,
                    byte[] ciphertext,
                    int ciphertextOffset)
             throws CryptoTokenException

Description copied from interface: BlockEncryptorEngine

Encrypts a block of the given plaintext into a block of ciphertext.

Specified by:

encrypt in interface BlockEncryptorEngine

Since:

JDE 3.7.0

Category:

Signed: This element is only accessible by signed clients. If you intend to use this element, please contact RIM to establish the necessary agreements that will allow you to have your COD files signed. Signing is only required for use on the device, development under the JDE can occur without signing the CODs.