Package org.bouncycastle.crypto.modes

Class GCFBBlockCipher

java.lang.Object

org.bouncycastle.crypto.StreamBlockCipher

org.bouncycastle.crypto.modes.GCFBBlockCipher

All Implemented Interfaces:

BlockCipher, StreamCipher

public class GCFBBlockCipher
extends StreamBlockCipher

An implementation of the GOST CFB mode with CryptoPro key meshing as described in RFC 4357.

Constructor Summary

Constructors

Constructor	Description
GCFBBlockCipher(BlockCipher engine)

Method Summary

Modifier and Type	Method	Description
protected byte	calculateByte(byte b)
String	getAlgorithmName()	Return the name of the algorithm the cipher implements.
int	getBlockSize()	Return the block size for this cipher (in bytes).
void	init(boolean forEncryption, CipherParameters params)	Initialise the cipher.
int	processBlock(byte[] in, int inOff, byte[] out, int outOff)	Process one block of input from the array in and write it to the out array.
void	reset()	Reset the cipher.

Methods inherited from class org.bouncycastle.crypto.StreamBlockCipher

getUnderlyingCipher, processBytes, returnByte

Methods inherited from class java.lang.Object

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

Constructor Details

GCFBBlockCipher

public GCFBBlockCipher(BlockCipher engine)

Method Details

init

public void init(boolean forEncryption,
 CipherParameters params)
          throws IllegalArgumentException

Description copied from interface: BlockCipher

Initialise the cipher.

Parameters:

forEncryption - if true the cipher is initialised for encryption, if false for decryption.

params - the key and other data required by the cipher.

Throws:

IllegalArgumentException - if the params argument is inappropriate.

getAlgorithmName

public String getAlgorithmName()

Description copied from interface: BlockCipher

Return the name of the algorithm the cipher implements.

Returns:

the name of the algorithm the cipher implements.

getBlockSize

public int getBlockSize()

Description copied from interface: BlockCipher

Return the block size for this cipher (in bytes).

Returns:

the block size for this cipher in bytes.

processBlock

public int processBlock(byte[] in,
 int inOff,
 byte[] out,
 int outOff)
                 throws DataLengthException,
IllegalStateException

Description copied from interface: BlockCipher

Process one block of input from the array in and write it to the out array.

Parameters:

in - the array containing the input data.

inOff - offset into the in array the data starts at.

out - the array the output data will be copied into.

outOff - the offset into the out array the output will start at.

Returns:

the number of bytes processed and produced.

Throws:

DataLengthException - if there isn't enough data in in, or space in out.

IllegalStateException - if the cipher isn't initialised.

calculateByte

protected byte calculateByte(byte b)

Specified by:

calculateByte in class StreamBlockCipher

reset

public void reset()

Description copied from interface: BlockCipher

Reset the cipher. After resetting the cipher is in the same state as it was after the last init (if there was one).