org.bouncycastle.crypto.engines
Class GOST28147Engine

java.lang.Object
  org.bouncycastle.crypto.engines.GOST28147Engine

All Implemented Interfaces:

BlockCipher

public class GOST28147Engine
extends java.lang.Object
implements BlockCipher

implementation of GOST 28147-89

Field Summary

protected static int	BLOCK_SIZE
private static byte[]	DSbox_A
private static byte[]	DSbox_Test
private static byte[]	ESbox_A
private static byte[]	ESbox_B
private static byte[]	ESbox_C
private static byte[]	ESbox_D
private static byte[]	ESbox_Test
private boolean	forEncryption
private byte[]	S
private static java.util.Hashtable	sBoxes
private int[]	workingKey

Constructor Summary

GOST28147Engine()
standard constructor.

Method Summary

private int	bytesToint(byte[] in, int inOff)
private int[]	generateWorkingKey(boolean forEncryption, byte[] userKey)
java.lang.String	getAlgorithmName() Return the name of the algorithm the cipher implements.
int	getBlockSize() Return the block size for this cipher (in bytes).
static byte[]	getSBox(java.lang.String sBoxName) Return the S-Box associated with SBoxName
private int	GOST28147_mainStep(int n1, int key)
private void	GOST28147Func(int[] workingKey, byte[] in, int inOff, byte[] out, int outOff)
void	init(boolean forEncryption, CipherParameters params) initialise an GOST28147 cipher.
private void	intTobytes(int num, byte[] out, int outOff)
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 java.lang.Object

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

Field Detail

BLOCK_SIZE

protected static final int BLOCK_SIZE

See Also:

Constant Field Values

workingKey

private int[] workingKey

forEncryption

private boolean forEncryption

S

private byte[] S

ESbox_Test

private static byte[] ESbox_Test

ESbox_A

private static byte[] ESbox_A

ESbox_B

private static byte[] ESbox_B

ESbox_C

private static byte[] ESbox_C

ESbox_D

private static byte[] ESbox_D

DSbox_Test

private static byte[] DSbox_Test

DSbox_A

private static byte[] DSbox_A

sBoxes

private static java.util.Hashtable sBoxes

Constructor Detail

GOST28147Engine

public GOST28147Engine()

standard constructor.

Method Detail

init

public void init(boolean forEncryption,
                 CipherParameters params)

initialise an GOST28147 cipher.

Specified by:

init in interface BlockCipher

Parameters:

forEncryption - whether or not we are for encryption.

params - the parameters required to set up the cipher.

Throws:

java.lang.IllegalArgumentException - if the params argument is inappropriate.

getAlgorithmName

public java.lang.String getAlgorithmName()

Description copied from interface: BlockCipher

Return the name of the algorithm the cipher implements.

Specified by:

getAlgorithmName in interface BlockCipher

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).

Specified by:

getBlockSize in interface BlockCipher

Returns:

the block size for this cipher in bytes.

processBlock

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

Description copied from interface: BlockCipher

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

Specified by:

processBlock in interface BlockCipher

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.

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).

Specified by:

reset in interface BlockCipher

generateWorkingKey

private int[] generateWorkingKey(boolean forEncryption,
                                 byte[] userKey)

GOST28147_mainStep

private int GOST28147_mainStep(int n1,
                               int key)

GOST28147Func

private void GOST28147Func(int[] workingKey,
                           byte[] in,
                           int inOff,
                           byte[] out,
                           int outOff)

bytesToint

private int bytesToint(byte[] in,
                       int inOff)

intTobytes

private void intTobytes(int num,
                        byte[] out,
                        int outOff)

getSBox

public static byte[] getSBox(java.lang.String sBoxName)

Return the S-Box associated with SBoxName

Parameters:

sBoxName - name of the S-Box

Returns:

byte array representing the S-Box