cryptix.provider.elgamal

Class BaseElGamalPrivateKey

java.lang.Object

cryptix.provider.elgamal.BaseElGamalPublicKey

cryptix.provider.elgamal.BaseElGamalPrivateKey

All Implemented Interfaces:

java.io.Serializable, java.security.Key, java.security.PrivateKey, java.security.PublicKey, ElGamalKey, ElGamalPrivateKey, ElGamalPublicKey

public class BaseElGamalPrivateKey
extends BaseElGamalPublicKey
implements ElGamalPrivateKey

A class representing an ElGamal private key. This can also act as an ElGamal public key. It is called BaseElGamalPrivateKey to distinguish it from the interface ElGamalPrivateKey, without having to use fully-qualified names.

References:

1. Bruce Schneier, "Section 19.6 ElGamal," Applied Cryptography, 2nd Edition, John Wiley & Sons, 1996.

2. IEEE P1363 draft standard, http://stdsbbs.ieee.org/groups/1363/index.html

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

$Revision: 1.2 $

Since:

Cryptix 2.2.2

Author:

David Hopwood

See Also:

ElGamalKey, java.security.Cipher, Signature, Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected java.math.BigInteger	x

Fields inherited from class cryptix.provider.elgamal.BaseElGamalPublicKey

g, p, y

Fields inherited from interface java.security.PrivateKey

serialVersionUID

Fields inherited from interface java.security.PublicKey

serialVersionUID

Constructor Summary

Constructors

Modifier	Constructor and Description
	BaseElGamalPrivateKey(java.math.BigInteger p, java.math.BigInteger g, java.math.BigInteger x) Constructs a BaseElGamalPrivateKey with the specified prime p, base g, and private value x.
	BaseElGamalPrivateKey(java.math.BigInteger p, java.math.BigInteger g, java.math.BigInteger x, java.math.BigInteger y) Constructs a BaseElGamalPrivateKey with the specified prime p, base g, private value x, and pre-calculated public value y = gx mod p.
protected	BaseElGamalPrivateKey(ElGamalParams params, java.math.BigInteger x) Constructs a BaseElGamalPublicKey with a prime and base taken from an object implementing java.security.interfaces.ElGamalParams, and the specified private value x.

Method Summary

Methods

Modifier and Type	Method and Description
java.math.BigInteger	getX() Returns the value of x (the private key).

Methods inherited from class cryptix.provider.elgamal.BaseElGamalPublicKey

getAlgorithm, getEncoded, getFormat, getG, getP, getY

Methods inherited from class java.lang.Object

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

Methods inherited from interface xjava.security.interfaces.ElGamalKey

getG, getP, getY

Methods inherited from interface java.security.Key

getAlgorithm, getEncoded, getFormat

Field Detail

x

protected java.math.BigInteger x

Constructor Detail

BaseElGamalPrivateKey

public BaseElGamalPrivateKey(java.math.BigInteger p,
                     java.math.BigInteger g,
                     java.math.BigInteger x,
                     java.math.BigInteger y)

Constructs a BaseElGamalPrivateKey with the specified prime p, base g, private value x, and pre-calculated public value y = gx mod p.

Parameters:

p - the prime as a java.math.BigInteger

g - the base as a java.math.BigInteger

x - the value of x as a java.math.BigInteger

y - the value of y as a java.math.BigInteger

Throws:

java.lang.NullPointerException - if p == null || g == null || x == null || y == null

BaseElGamalPrivateKey

public BaseElGamalPrivateKey(java.math.BigInteger p,
                     java.math.BigInteger g,
                     java.math.BigInteger x)

Constructs a BaseElGamalPrivateKey with the specified prime p, base g, and private value x.

The public value y = gx mod p will be calculated.

Parameters:

p - the prime as a java.math.BigInteger

g - the base as a java.math.BigInteger

x - the value of x as a java.math.BigInteger

Throws:

java.lang.NullPointerException - if p == null || g == null || x == null

BaseElGamalPrivateKey

protected BaseElGamalPrivateKey(ElGamalParams params,
                     java.math.BigInteger x)

Constructs a BaseElGamalPublicKey with a prime and base taken from an object implementing java.security.interfaces.ElGamalParams, and the specified private value x.

The public value y = gx mod p will be calculated.

Parameters:

params - the parameters for this key

x - the value of x as a java.math.BigInteger

Throws:

java.lang.NullPointerException - if params == null || x == null

See Also:

ElGamalParams

Method Detail

getX

public java.math.BigInteger getX()

Returns the value of x (the private key).

Specified by:

getX in interface ElGamalPrivateKey

Returns:

x as a java.math.BigInteger