com.mindbright.jce.crypto
Class Cipher

java.lang.Object
  com.mindbright.jce.crypto.Cipher

public class Cipher
extends java.lang.Object

Field Summary

static int	DECRYPT_MODE
static int	ENCRYPT_MODE

Constructor Summary

protected

Cipher(CipherSpi cipherSpi, Provider provider, java.lang.String transformation)

Method Summary

byte[]	doFinal(byte[] input) Encrypt the entire input array.
byte[]	doFinal(byte[] input, int inputOffset, int inputLen) Encrypt part of the input array
int	doFinal(byte[] input, int inputOffset, int inputLen, byte[] output) Encrypt part of the input array and stores the result in the given output array.
int	doFinal(byte[] input, int inputOffset, int inputLen, byte[] output, int outputOffset) Encrypt part of the input array and stores the result in the given output array.
java.lang.String	getAlgorithm() Get the name of the algorithm implemented by this Cipher instance.
int	getBlockSize() Get how big blocks this algorithm works on.
static Cipher	getInstance(java.lang.String transformation) Get a Cipher instance which implements the given algorithm in any of the registered providers.
static Cipher	getInstance(java.lang.String transformation, java.lang.String provider) Get a Cipher instance which implements the given algorithm in the given provider.
byte[]	getIV() Get the IV used by this instance
int	getOutputSize(int inputLen) Calculate how much encryted data an imput of the given length will cause.
Provider	getProvider() Get the provider which implements this algorithm.
void	init(int opmode, Key key) Initialize this Cipher instance.
void	init(int opmode, Key key, AlgorithmParameterSpec params) Initialize this Cipher instance.

Methods inherited from class java.lang.Object

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

Field Detail

DECRYPT_MODE

public static final int DECRYPT_MODE

See Also:

Constant Field Values

ENCRYPT_MODE

public static final int ENCRYPT_MODE

See Also:

Constant Field Values

Constructor Detail

Cipher

protected Cipher(CipherSpi cipherSpi,
                 Provider provider,
                 java.lang.String transformation)

Method Detail

doFinal

public final byte[] doFinal(byte[] input)

Encrypt the entire input array.

Note that the input must be a multiple of the block size bytes long.

Parameters:

input - array of data to encrypt

Returns:

the encrypted data

doFinal

public final byte[] doFinal(byte[] input,
                            int inputOffset,
                            int inputLen)

Encrypt part of the input array

Note that the input must be a multiple of the block size bytes long.

Parameters:

input - array of data to encrypt

inputOffset - start of data to encrypt

inputLen - length of data to encrypt

Returns:

the encrypted data

doFinal

public final int doFinal(byte[] input,
                         int inputOffset,
                         int inputLen,
                         byte[] output)

Encrypt part of the input array and stores the result in the given output array.

Note that the input must be a multiple of the block size bytes long.

Parameters:

input - array of data to encrypt

inputOffset - start of data to encrypt

inputLen - length of data to encrypt

output - array in which output is stored. This array must have room for at least getOutputSize(inputLen) bytes

Returns:

the number of bytes store in the output array

doFinal

public final int doFinal(byte[] input,
                         int inputOffset,
                         int inputLen,
                         byte[] output,
                         int outputOffset)

Encrypt part of the input array and stores the result in the given output array.

Note that the input must be a multiple of the block size bytes long.

Parameters:

input - array of data to encrypt

inputOffset - start of data to encrypt

inputLen - length of data to encrypt

output - array in which output is stored. This array must have room for at least getOutputSize(inputLen) bytes

outputOffset - Start offset in the output array where the output should be stored.

Returns:

the number of bytes store in the output array

getAlgorithm

public final java.lang.String getAlgorithm()

Get the name of the algorithm implemented by this Cipher instance.

Returns:

algorithm name

getBlockSize

public final int getBlockSize()

Get how big blocks this algorithm works on.

Returns:

the block size (in bytes)

getInstance

public static final Cipher getInstance(java.lang.String transformation)
                                throws NoSuchAlgorithmException

Get a Cipher instance which implements the given algorithm in any of the registered providers.

Parameters:

transformation - name of the desired algorithm (like AES/CBC).

Returns:

a Cipher instance implementing the algorithm

Throws:

NoSuchAlgorithmException - if no implementation can be found

getInstance

public static final Cipher getInstance(java.lang.String transformation,
                                       java.lang.String provider)
                                throws NoSuchAlgorithmException,
                                       NoSuchProviderException

Get a Cipher instance which implements the given algorithm in the given provider.

Parameters:

transformation - name of the desired algorithm (like AES/CBC).

Returns:

a Cipher instance implementing the algorithm

Throws:

NoSuchAlgorithmException - if no implementation can be found

NoSuchProviderException

getIV

public final byte[] getIV()

Get the IV used by this instance

getOutputSize

public final int getOutputSize(int inputLen)

Calculate how much encryted data an imput of the given length will cause.

Parameters:

inputLen - length of input data

Returns:

number of bytes output

getProvider

public final Provider getProvider()

Get the provider which implements this algorithm.

init

public final void init(int opmode,
                       Key key)
                throws InvalidKeyException

Initialize this Cipher instance.

Parameters:

opmode - The operating mode. This should be either Cipher.ENCRYPT_MODE or Cipher.DECRYPT_MODE.

key - the encryption or decryption key

Throws:

InvalidKeyException

init

public final void init(int opmode,
                       Key key,
                       AlgorithmParameterSpec params)
                throws InvalidKeyException

Initialize this Cipher instance.

Parameters:

opmode - The operating mode. This should be either Cipher.ENCRYPT_MODE or Cipher.DECRYPT_MODE.

key - the encryption or decryption key

params - Extra algorithm parameters

Throws:

InvalidKeyException