org.bouncycastle.crypto.macs
Class GOST28147Mac

java.lang.Object
  org.bouncycastle.crypto.macs.GOST28147Mac

All Implemented Interfaces:

Mac

public class GOST28147Mac
extends java.lang.Object
implements Mac

implementation of GOST 28147-89 MAC

Field Summary

private int	blockSize
private byte[]	buf
private int	bufOff
private boolean	firstStep
private byte[]	mac
private int	macSize
private byte[]	S
private int[]	workingKey

Constructor Summary

GOST28147Mac()

Method Summary

private int	bytesToint(byte[] in, int inOff)
private byte[]	CM5func(byte[] buf, int bufOff, byte[] mac)
int	doFinal(byte[] out, int outOff) Compute the final statge of the MAC writing the output to the out parameter.
private int[]	generateWorkingKey(byte[] userKey)
java.lang.String	getAlgorithmName() Return the name of the algorithm the MAC implements.
int	getMacSize() Return the block size for this MAC (in bytes).
private int	gost28147_mainStep(int n1, int key)
private void	gost28147MacFunc(int[] workingKey, byte[] in, int inOff, byte[] out, int outOff)
void	init(CipherParameters params) Initialise the MAC.
private void	intTobytes(int num, byte[] out, int outOff)
void	reset() Reset the MAC.
void	update(byte in) add a single byte to the mac for processing.
void	update(byte[] in, int inOff, int len)

Methods inherited from class java.lang.Object

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

Field Detail

blockSize

private int blockSize

macSize

private int macSize

bufOff

private int bufOff

buf

private byte[] buf

mac

private byte[] mac

firstStep

private boolean firstStep

workingKey

private int[] workingKey

S

private byte[] S

Constructor Detail

GOST28147Mac

public GOST28147Mac()

Method Detail

generateWorkingKey

private int[] generateWorkingKey(byte[] userKey)

init

public void init(CipherParameters params)
          throws java.lang.IllegalArgumentException

Description copied from interface: Mac

Initialise the MAC.

Specified by:

init in interface Mac

Parameters:

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

Throws:

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

getAlgorithmName

public java.lang.String getAlgorithmName()

Description copied from interface: Mac

Return the name of the algorithm the MAC implements.

Specified by:

getAlgorithmName in interface Mac

Returns:

the name of the algorithm the MAC implements.

getMacSize

public int getMacSize()

Description copied from interface: Mac

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

Specified by:

getMacSize in interface Mac

Returns:

the block size for this MAC in bytes.

gost28147_mainStep

private int gost28147_mainStep(int n1,
                               int key)

gost28147MacFunc

private void gost28147MacFunc(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)

CM5func

private byte[] CM5func(byte[] buf,
                       int bufOff,
                       byte[] mac)

update

public void update(byte in)
            throws java.lang.IllegalStateException

Description copied from interface: Mac

add a single byte to the mac for processing.

Specified by:

update in interface Mac

Parameters:

in - the byte to be processed.

Throws:

java.lang.IllegalStateException - if the MAC is not initialised.

update

public void update(byte[] in,
                   int inOff,
                   int len)
            throws DataLengthException,
                   java.lang.IllegalStateException

Specified by:

update in interface Mac

Parameters:

in - the array containing the input.

inOff - the index in the array the data begins at.

len - the length of the input starting at inOff.

Throws:

DataLengthException - if there isn't enough data in in.

java.lang.IllegalStateException - if the MAC is not initialised.

doFinal

public int doFinal(byte[] out,
                   int outOff)
            throws DataLengthException,
                   java.lang.IllegalStateException

Description copied from interface: Mac

Compute the final statge of the MAC writing the output to the out parameter.

doFinal leaves the MAC in the same state it was after the last init.

Specified by:

doFinal in interface Mac

Parameters:

out - the array the MAC is to be output to.

outOff - the offset into the out buffer the output is to start at.

Throws:

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

java.lang.IllegalStateException - if the MAC is not initialised.

reset

public void reset()

Description copied from interface: Mac

Reset the MAC. At the end of resetting the MAC should be in the in the same state it was after the last init (if there was one).

Specified by:

reset in interface Mac