de.flexiprovider.core.mersa
Class MeRSA

java.lang.Object
  |
  +--javax.crypto.CipherSpi
        |
        +--de.flexiprovider.api.Cipher
              |
              +--de.flexiprovider.api.AsymmetricBlockCipher
                    |
                    +--de.flexiprovider.core.mersa.MeRSA

public class MeRSA

extends AsymmetricBlockCipher

This class implements the Multi-Exponent RSA algorithm in the OAEP (Optimal Asymmetric Encryption Padding) mode. The OAEP mode is recommended for new applications.

Author:

Erik Dahmen, Paul Nguentcheu

Fields inherited from class de.flexiprovider.api.AsymmetricBlockCipher

buf, cipherTextSize, maxPlainTextSize, paramSpec

Fields inherited from class de.flexiprovider.api.Cipher

DECRYPT_MODE, ENCRYPT_MODE, opMode

Constructor Summary

MeRSA()

Method Summary

int	getKeySize(Key key) Returns the key size of the given key object.
java.lang.String	getName()
protected void	initCipherDecrypt(Key key, AlgorithmParameterSpec params) This method initializes the block cipher with a certain key and parameters for data encryption.
protected void	initCipherEncrypt(Key key, AlgorithmParameterSpec params, SecureRandom secureRandom) This method initializes the block cipher with a certain key and parameters for data encryption.
protected byte[]	messageDecrypt(byte[] input) Decrypt a ciphertext.
protected byte[]	messageEncrypt(byte[] input) Encrypt a message.

Methods inherited from class de.flexiprovider.api.AsymmetricBlockCipher

checkLength, doFinal, doFinal, getBlockSize, getIV, getOutputSize, getParameters, initDecrypt, initDecrypt, initEncrypt, initEncrypt, initEncrypt, initEncrypt, setMode, setPadding, update, update

Methods inherited from class de.flexiprovider.api.Cipher

doFinal, doFinal, engineDoFinal, engineDoFinal, engineGetBlockSize, engineGetIV, engineGetKeySize, engineGetOutputSize, engineGetParameters, engineInit, engineInit, engineInit, engineSetMode, engineSetPadding, engineUpdate, engineUpdate, update

Methods inherited from class java.lang.Object

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

Constructor Detail

MeRSA

public MeRSA()

Method Detail

getName

public final java.lang.String getName()

Overrides:

getName in class Cipher

Returns:

the name of this cipher

getKeySize

public int getKeySize(Key key)
               throws InvalidKeyException

Returns the key size of the given key object. Checks whether the key object is an instance of RSAPublicKey or MeRSAPrivateKey. Would be simpler to just check for RSAKey but this breaks build with Java 1.2.

Overrides:

getKeySize in class Cipher

Parameters:

key - the key object

Returns:

the key size of the given key object.

Throws:

InvalidKeyException - if key is invalid.

initCipherEncrypt

protected void initCipherEncrypt(Key key,
                                 AlgorithmParameterSpec params,
                                 SecureRandom secureRandom)
                          throws InvalidKeyException

This method initializes the block cipher with a certain key and parameters for data encryption.

Overrides:

initCipherEncrypt in class AsymmetricBlockCipher

Parameters:

key - - the key which has to be used to encrypt data

params - - the algorithm parameters

secureRandom - - the source of randomness

Throws:

InvalidKeyException - if the given key is inappropriate for initializing this cipher.

initCipherDecrypt

protected void initCipherDecrypt(Key key,
                                 AlgorithmParameterSpec params)
                          throws InvalidKeyException

This method initializes the block cipher with a certain key and parameters for data encryption.

Overrides:

initCipherDecrypt in class AsymmetricBlockCipher

Parameters:

key - - the key which has to be used to decrypt data

params - - the algorithm parameters

Throws:

InvalidKeyException - if the given key is inappropriate for initializing this cipher.

messageEncrypt

protected byte[] messageEncrypt(byte[] input)

Encrypt a message.

Overrides:

messageEncrypt in class AsymmetricBlockCipher

Parameters:

input - - the plaintext

Returns:

the encrypted plaintext

messageDecrypt

protected byte[] messageDecrypt(byte[] input)

Decrypt a ciphertext.

Overrides:

messageDecrypt in class AsymmetricBlockCipher

Parameters:

input - - the ciphertext

Returns:

the decrypted ciphertext