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

Creates a CAST 128 decryption engine. The CAST algorithm was designed by Carlisle Adams and Stafford Tavares. This version of CAST has a 128 bit key and a 64 bit block size.

This cipher is available worldwide on a royalty-free basis for commercial and non-commercial use.

For more information please refer to RFC 2144.

(@link CAST128Key More information on the key used in this engine.)

Category:

Signed: This element is only accessible by signed applications. If you intend to use this element, please visit http://www.blackberry.com/go/codesigning to obtain a set of code signing keys. Code signing is only required for applications running on BlackBerry smartphones; development on BlackBerry Smartphone Simulators can occur without code signing.

Since:

BlackBerry API 3.6.0

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.

See Also:

Constant Field Values

Category:

Signed: This element is only accessible by signed applications. If you intend to use this element, please visit http://www.blackberry.com/go/codesigning to obtain a set of code signing keys. Code signing is only required for applications running on BlackBerry smartphones; development on BlackBerry Smartphone Simulators can occur without code signing.

Since:

BlackBerry API 3.6.0

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 applications. If you intend to use this element, please visit http://www.blackberry.com/go/codesigning to obtain a set of code signing keys. Code signing is only required for applications running on BlackBerry smartphones; development on BlackBerry Smartphone Simulators can occur without code signing.

Since:

BlackBerry API 3.6.0

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 applications. If you intend to use this element, please visit http://www.blackberry.com/go/codesigning to obtain a set of code signing keys. Code signing is only required for applications running on BlackBerry smartphones; development on BlackBerry Smartphone Simulators can occur without code signing.

Since:

BlackBerry API 3.6.0

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

Returns:

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

Category:

Signed: This element is only accessible by signed applications. If you intend to use this element, please visit http://www.blackberry.com/go/codesigning to obtain a set of code signing keys. Code signing is only required for applications running on BlackBerry smartphones; development on BlackBerry Smartphone Simulators can occur without code signing.

Since:

BlackBerry API 3.6.0

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

Parameters:

ciphertext - A byte array containing the input that is to be decrypted.

ciphertextOffset - The starting offset, or initial byte position, of the data within the input array.

plaintext - A byte array containing the output from the method.

plaintextOffset - The starting offset, or initial byte position, of the data within the output array.

Throws:

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

Category:

Signed: This element is only accessible by signed applications. If you intend to use this element, please visit http://www.blackberry.com/go/codesigning to obtain a set of code signing keys. Code signing is only required for applications running on BlackBerry smartphones; development on BlackBerry Smartphone Simulators can occur without code signing.

Since:

BlackBerry API 3.6.0