de.flexiprovider.core.mac
Class CBCMac

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

Direct Known Subclasses:

CBCMac.AES128, CBCMac.AES192, CBCMac.AES256, CBCMac.Camellia, CBCMac.DESede, CBCMac.IDEA, CBCMac.MARS, CBCMac.Misty1, CBCMac.RC2, CBCMac.RC5, CBCMac.RC6, CBCMac.SAFERPlus, CBCMac.SAFERPlusPlus, CBCMac.Serpent, CBCMac.Shacal, CBCMac.Shacal2, CBCMac.Twofish

public abstract class CBCMac

extends Mac

This is an implementation of the CBC MAC (ANSI X9.9) using the "flexicore" jce implementation. Padding is only to put 0x00 until block boundary . We emulate (single) DES by initializing all three parts of the key identically. For reference look at V. Oorschot et. al. Handbook of Applied Cryptography chapter 9.5.1 As here is no support for this algorithm directly it is constructed using the following steps: 1. generating (single)des encryption over cipher1Input value using following algorithm: Cipher.getInstance("DESede/CBC/NoPadding","FlexiCore"); 1. creating an triple-DES key equivalent to DES by choosing keyA=keyB=keyC = key1 2. decrypting result with algorithm Cipher.getInstance("DESede","FlexiCore"); using key keyA=keyB=keyC = key2 3. encrypting result with algorithm Cipher.getInstance("DESede","FlexiCore"); using key keyA=keyB=keyC = key1

Author:

Paul Nguentcheu

Inner Class Summary

static class	CBCMac.AES128 CBC-MAC with AES128 algorithm
static class	CBCMac.AES192 CBC-MAC with AES192 algorithm
static class	CBCMac.AES256 CBC-MAC with AES256 algorithm
static class	CBCMac.Camellia CBC-MAC with Camellia algorithm
static class	CBCMac.DESede CBC-MAC with DESede algorithm
static class	CBCMac.IDEA CBC-MAC with IDEA algorithm
static class	CBCMac.MARS CBC-MAC with MARS algorithm
static class	CBCMac.Misty1 CBC-MAC with Misty1 algorithm
static class	CBCMac.RC2 CBC-MAC with RC2 algorithm
static class	CBCMac.RC5 CBC-MAC with RC5 algorithm
static class	CBCMac.RC6 CBC-MAC with RC6 algorithm
static class	CBCMac.SAFERPlus CBC-MAC with SAFERPlus algorithm
static class	CBCMac.SAFERPlusPlus CBC-MAC with SAFERPlusPlus algorithm
static class	CBCMac.Serpent CBC-MAC with Serpent algorithm
static class	CBCMac.Shacal CBC-MAC with Shacal algorithm
static class	CBCMac.Shacal2 CBC-MAC with Shacal2 algorithm
static class	CBCMac.Twofish CBC-MAC with Twofish algorithm

Constructor Summary

protected

CBCMac(BlockCipher blockCipher) This constructor is called by every subclass for specifying the particular algorithm to be used for CBC-MAC computation.

Method Summary

byte[]	doFinal() Return the computed MAC value.
int	getMacLength() Return the MAC length.
void	init(SecretKey key, AlgorithmParameterSpec params) Initialize this MAC with the given secret key and parameters.
void	reset() Reset this MAC object so that it may be used for further MAC computations.
void	update(byte input) Process the given byte
void	update(byte[] input, int inOff, int inLen) Process 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

CBCMac

protected CBCMac(BlockCipher blockCipher)

This constructor is called by every subclass for specifying the particular algorithm to be used for CBC-MAC computation.

Parameters:

blockCipher - the cipher algorithm to use

Method Detail

getMacLength

public int getMacLength()

Description copied from class: Mac

Return the MAC length. This method is guaranteed to return a sane value only after the MAC has been initialized.

Overrides:

getMacLength in class Mac

Returns:

the length of the MAC value in bytes

init

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

Initialize this MAC with the given secret key and parameters.

Overrides:

init in class Mac

Parameters:

key - the secret key

params - the parameters

Throws:

InvalidKeyException - if the key is invalid.

InvalidAlgorithmParameterException - if the parameters are invalid.

update

public void update(byte input)

Process the given byte

Overrides:

update in class Mac

Parameters:

input - the byte to be processed

update

public void update(byte[] input,
                   int inOff,
                   int inLen)

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

Overrides:

update in class Mac

Parameters:

input - byte array containing the message to be processed

inOff - offset into the array to start from

inLen - number of bytes to be processed

doFinal

public byte[] doFinal()

Return the computed MAC value. After the MAC has been calculated, the MAC object is reset for further computations.

Overrides:

doFinal in class Mac

Returns:

the computed MAC value

reset

public void reset()

Reset this MAC object so that it may be used for further MAC computations.

Overrides:

reset in class Mac