cryptix.provider.md

Class HAVAL

java.lang.Object

java.security.MessageDigestSpi

java.security.MessageDigest

cryptix.provider.md.HAVAL

All Implemented Interfaces:

java.lang.Cloneable, Parameterized, VariableLengthDigest

public class HAVAL
extends java.security.MessageDigest
implements Parameterized, VariableLengthDigest, java.lang.Cloneable

A Java class to digest input according to the HAVAL algorithm.

HAVAL is a variable length MD with a variable number of passes. The values for these two parameters are read from the provider '.properties' file. Here is an example of the two property lines that do that:

    Alg.passes.HAVAL = 3
    Alg.bitLength.HAVAL = 256
 

References:

1. Y. Zheng, J. Pieprzyk and J. Seberry, "HAVAL --- a one-way hashing algorithm with variable length of output", Advances in Cryptology --- AUSCRYPT'92, Lecture Notes in Computer Science, Springer-Verlag, 1993.

   Copyright © 1997 Systemics Ltd on behalf of the Cryptix Development Team.
   All rights reserved.

   $Revision: 1.5 $

Since:

Cryptix 2.2.2

Author:

Raif S. Naffah, David Hopwood

Constructor Summary

Constructors

Constructor and Description
HAVAL()

Method Summary

Modifier and Type	Method and Description
java.lang.Object	clone() Returns a copy of this MD object.
protected byte[]	engineDigest() Completes the hash computation by performing final operations such as padding.
protected int	engineGetDigestLength() SPI: Returns the digest length in bytes.
protected java.lang.Object	engineGetParameter(java.lang.String param)
protected void	engineReset() Resets this object disregarding any temporary data present at the time of the invocation of this call.
protected void	engineSetParameter(java.lang.String param, java.lang.Object value)
protected void	engineUpdate(byte input) Continues a HAVAL message digest using the input byte.
protected void	engineUpdate(byte[] input, int offset, int len) Hashes a byte array from a given offset for a specified length.
static LinkStatus	getLinkStatus()
java.lang.Object	getParameter(java.lang.String param) Gets the value of the specified algorithm parameter.
void	setBitLength(int len) Sets the output length of this HAVAL object in bits, resetting all internal variables.
void	setDigestLength(int len) Sets the output length of this HAVAL object in bytes, resetting all internal variables.
void	setParameter(java.lang.String param, java.lang.Object value) Sets the specified algorithm parameter to the specified value.
void	setPasses(int p) Sets the number of passes for this HAVAL object, resetting all internal variables.

Methods inherited from class java.security.MessageDigest

digest, digest, digest, getAlgorithm, getDigestLength, getInstance, getInstance, getInstance, getProvider, isEqual, reset, toString, update, update, update, update

Methods inherited from class java.security.MessageDigestSpi

engineDigest, engineUpdate

Methods inherited from class java.lang.Object

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

Constructor Detail

HAVAL

public HAVAL()

Method Detail

getLinkStatus

public static LinkStatus getLinkStatus()

clone

public java.lang.Object clone()

Returns a copy of this MD object.

Overrides:

clone in class java.security.MessageDigest

engineReset

protected void engineReset()

Resets this object disregarding any temporary data present at the time of the invocation of this call.

Specified by:

engineReset in class java.security.MessageDigestSpi

engineUpdate

protected void engineUpdate(byte input)

Continues a HAVAL message digest using the input byte.

Specified by:

engineUpdate in class java.security.MessageDigestSpi

engineUpdate

protected void engineUpdate(byte[] input,
                            int offset,
                            int len)

Hashes a byte array from a given offset for a specified length. to be used in conjunction with engineReset() and finish().

Specified by:

engineUpdate in class java.security.MessageDigestSpi

Parameters:

input - byte array from which data is to be hashed.

offset - start index of bytes to hash in input.

len - number of bytes to hash.

engineDigest

protected byte[] engineDigest()

Completes the hash computation by performing final operations such as padding. At the return of this engineDigest, the MD engine is reset.

Specified by:

engineDigest in class java.security.MessageDigestSpi

Returns:

the array of bytes for the resulting hash value.

engineGetDigestLength

protected int engineGetDigestLength()

SPI: Returns the digest length in bytes.

Overrides:

engineGetDigestLength in class java.security.MessageDigestSpi

setParameter

public void setParameter(java.lang.String param,
                         java.lang.Object value)
                  throws NoSuchParameterException,
                         java.security.InvalidParameterException,
                         InvalidParameterTypeException

Description copied from interface: Parameterized

Sets the specified algorithm parameter to the specified value.

This method supplies a general-purpose mechanism through which it is possible to set the various parameters of this object. A uniform algorithm-specific naming scheme for each parameter is desirable but left unspecified at this time.

Specified by:

setParameter in interface Parameterized

Parameters:

param - the string identifier of the parameter.

value - the parameter value.

Throws:

NoSuchParameterException - if there is no parameter with name param for this cipher implementation.

java.security.InvalidParameterException - if the parameter exists but cannot be set (for example because the object is in the wrong state).

InvalidParameterTypeException - if value is the wrong type for this parameter.

getParameter

public java.lang.Object getParameter(java.lang.String param)
                              throws NoSuchParameterException,
                                     java.security.InvalidParameterException

Description copied from interface: Parameterized

Gets the value of the specified algorithm parameter.

This method supplies a general-purpose mechanism through which it is possible to get the various parameters of this object. A uniform algorithm-specific naming scheme for each parameter is desirable but left unspecified at this time.

Specified by:

getParameter in interface Parameterized

Parameters:

param - the string name of the parameter.

Returns:

the object that represents the parameter value.

Throws:

NoSuchParameterException - if there is no parameter with name param for this implementation.

java.security.InvalidParameterException - if the parameter exists but cannot be read.

engineSetParameter

protected void engineSetParameter(java.lang.String param,
                                  java.lang.Object value)
                           throws NoSuchParameterException,
                                  java.security.InvalidParameterException,
                                  InvalidParameterTypeException

Throws:

NoSuchParameterException

java.security.InvalidParameterException

InvalidParameterTypeException

engineGetParameter

protected java.lang.Object engineGetParameter(java.lang.String param)
                                       throws NoSuchParameterException,
                                              java.security.InvalidParameterException

Throws:

NoSuchParameterException

java.security.InvalidParameterException

setPasses

public void setPasses(int p)

Sets the number of passes for this HAVAL object, resetting all internal variables.

setBitLength

public void setBitLength(int len)

Sets the output length of this HAVAL object in bits, resetting all internal variables.

setDigestLength

public void setDigestLength(int len)

Sets the output length of this HAVAL object in bytes, resetting all internal variables.

Specified by:

setDigestLength in interface VariableLengthDigest

Parameters:

len - the new length in bytes.