SHOW Signed

net.rim.device.api.crypto
Class CAST128DecryptorEngine

java.lang.Object
  |
  +--net.rim.device.api.crypto.CAST128DecryptorEngine

All Implemented Interfaces:

BlockDecryptorEngine, SymmetricKeyDecryptorEngine

public final class CAST128DecryptorEngine

extends Object

implements SymmetricKeyDecryptorEngine

The CAST128DecryptorEngine implements the decryption functionality of the CAST128 block cipher. CAST128 is defined in RFC 2144.

CAST128 operates on 64 bit blocks and has an effective key length of 128 bits. The algorithm is uses the basic principles of data confusion and diffusion.

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.

Field Summary

static int

BLOCK_LENGTH Represents the block length of the cipher in bytes, namely 8 bytes.

Constructor Summary

CAST128DecryptorEngine(CAST128Key key) Creates a CAST128DecryptorEngine object based on a given CAST128 key.

Method Summary

	void	decrypt(byte[] ciphertext, int ciphertextOffset, byte[] plaintext, int plaintextOffset) Decodes a block of the given ciphertext into a block of plaintext.
	String	getAlgorithm() Returns the name of the algorithm used, ie "CAST128".
	int	getBlockLength() Returns the block length of the block cipher in bytes.

Methods inherited from class java.lang.Object

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

Field Detail

BLOCK_LENGTH

public static final int BLOCK_LENGTH

Represents the block length of the cipher in bytes, namely 8 bytes.

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.

Constructor Detail

CAST128DecryptorEngine

public CAST128DecryptorEngine(CAST128Key key)
                       throws CryptoTokenException,
                              CryptoUnsupportedOperationException

Creates a CAST128DecryptorEngine object based on a given CAST128 key.

Parameters:

key - A CAST128 key containing the key material that will be used for decryption.

Throws:

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

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

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, ie "CAST128".

This method will always return the string "CAST128".

Specified by:

getAlgorithm in interface BlockDecryptorEngine

Returns:

A string representing the name of the algorithm.

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: BlockDecryptorEngine

Returns the block length of the block cipher in bytes.

Specified by:

getBlockLength in interface BlockDecryptorEngine

Following copied from interface: net.rim.device.api.crypto.BlockDecryptorEngine

Returns:

An integer that specifies the length of a block of data.

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.

decrypt

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

Description copied from interface: BlockDecryptorEngine

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

Specified by:

decrypt in interface BlockDecryptorEngine

Since:

JDE 3.6

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.