net.rim.device.api.crypto
Class RSADecryptorEngine

java.lang.Object
  net.rim.device.api.crypto.RSADecryptorEngine

All Implemented Interfaces:

BlockDecryptorEngine, PrivateKeyDecryptorEngine

public final class RSADecryptorEngine
extends Object
implements PrivateKeyDecryptorEngine

Provides the RSA decryption functionality on a block by block basis. The block length is the size of the modulus, which must be a multiple of 8.

A description of the RSA algorithm can be found in PKCS #1 version 2.1. We support this definition of RSA.

For a code sample using the RSA decryptor engine, click here.

See Also:

RSAEncryptorEngine, RSAKeyPair

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 Summary
	RSADecryptorEngine(RSAPrivateKey key) Creates an RSADecryptorEngine object given a private key that will be used for decrypting the ciphertext.

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 "RSA".
	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

Constructor Detail

RSADecryptorEngine

public RSADecryptorEngine(RSAPrivateKey key)
                   throws CryptoTokenException,
                          CryptoUnsupportedOperationException

Creates an RSADecryptorEngine object given a private key that will be used for decrypting the ciphertext. The modulus must be a multiple of 8.

Parameters:

key - The private key that will be used to decrypt the data. The private key is associated with the public key that was used to encrypt the data.

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.

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 "RSA".

This method will always return the String "RSA".

Specified by:

getAlgorithm in interface BlockDecryptorEngine

Returns:

A String that represents 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