de.flexiprovider.core.mac
Class TwoTrackMac

java.lang.Object
  |
  +--javax.crypto.MacSpi
        |
        +--de.flexiprovider.api.Mac
              |
              +--de.flexiprovider.core.mac.TwoTrackMac

Direct Known Subclasses:

TwoTrackMac.TTMac128, TwoTrackMac.TTMac160, TwoTrackMac.TTMac32, TwoTrackMac.TTMac64, TwoTrackMac.TTMac96

public abstract class TwoTrackMac

extends Mac

This class extends the Mac class for providing the functionality of the TTMAC(Two-Track-MAC) algorithm, as specified in the version 2.0 of the NESSIE final reports.

Any application dealing with MAC computation, uses the getInstance method of the MAC class for creating a MAC object.

The FlexiProvider supports TTMAC computation with 32, 64, 96, 128 and 160-bit output.

Author:

Paul Nguentcheu

Inner Class Summary

static class	TwoTrackMac.TTMac128
static class	TwoTrackMac.TTMac160
static class	TwoTrackMac.TTMac32
static class	TwoTrackMac.TTMac64
static class	TwoTrackMac.TTMac96

Constructor Summary

protected

TwoTrackMac(int len) Creates a new TTMac with the specified MAC length.

Method Summary

byte[]	doFinal() Returns the calculated MAC value.
int	getMacLength() Returns the length of the MAC in Bytes.
void	init(SecretKey key, AlgorithmParameterSpec params) Initializes the Object with the given secret key for the following MAC-calculations.
void	reset() Resets the MAC for further use, maintaining the secret key that the MAC was initialized with.
void	update(byte b) Processes the given byte
void	update(byte[] bytes, int offset, int len) Processes the given number of bytes, supplied in a byte array starting at the given position.

Methods inherited from class de.flexiprovider.api.Mac

doFinal, doFinal, engineDoFinal, engineGetMacLength, engineInit, engineReset, engineUpdate, engineUpdate, init, update

Methods inherited from class javax.crypto.MacSpi

clone

Methods inherited from class java.lang.Object

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

Constructor Detail

TwoTrackMac

protected TwoTrackMac(int len)

Creates a new TTMac with the specified MAC length.

Parameters:

len - the bitlength of the MAC. Possible lengths are 32, 64, 96, 128 and 160.

Method Detail

getMacLength

public int getMacLength()

Returns the length of the MAC in Bytes.

Overrides:

getMacLength in class Mac

Returns:

the length of the MAC.

init

public void init(SecretKey key,
                 AlgorithmParameterSpec params)
          throws InvalidKeyException

Initializes the Object with the given secret key for the following MAC-calculations.

Overrides:

init in class Mac

Parameters:

key - the secret key with which this MAC object is initialized..

params - the parameters are not used.

Throws:

InvalidKeyException - if the key size is invalid.

update

public void update(byte b)

Processes the given byte

Overrides:

update in class Mac

Parameters:

b - the byte to be processed.

update

public void update(byte[] bytes,
                   int offset,
                   int len)

Processes the given number of bytes, supplied in a byte array starting at the given position.

Overrides:

update in class Mac

Parameters:

bytes - byte array containing the message to be processed

offset - offset into the array to start from

len - number of bytes to be processed.

doFinal

public byte[] doFinal()

Returns the calculated MAC value. After the MAC finally has been calculated, the MAC object is reset for further MAC computations.

Overrides:

doFinal in class Mac

Returns:

the calculated MAC value.

reset

public void reset()

Resets the MAC for further use, maintaining the secret key that the MAC was initialized with.

Overrides:

reset in class Mac