Top Description Fields Constructors Methods
org.bouncycastle.crypto.ec

public Class ECFixedTransform

extends Object
implements ECPairFactorTransform
Class Inheritance
All Implemented Interfaces
org.bouncycastle.crypto.ec.ECPairFactorTransform, org.bouncycastle.crypto.ec.ECPairTransform
Imports
java.math.BigInteger, org.bouncycastle.crypto.CipherParameters, org.bouncycastle.crypto.params.ECDomainParameters, .ECPublicKeyParameters, org.bouncycastle.math.ec.ECAlgorithms, .ECMultiplier, .ECPoint, .FixedPointCombMultiplier
this transforms the original randomness used for an ElGamal encryption by a fixed value.

Field Summary

Modifier and TypeField and Description
private BigInteger
k

private ECPublicKeyParameters
key

Constructor Summary

AccessConstructor and Description
public
ECFixedTransform(BigInteger k)

Method Summary

Modifier and TypeMethod and Description
protected ECMultiplier
createBasePointMultiplier()

public BigInteger

Returns:

a BigInteger representing k value.
getTransformValue()

Implements org.bouncycastle.crypto.ec.ECPairFactorTransform.getTransformValue.

Return the last transform value used by the transform

public void
init(CipherParameters
the necessary EC key parameters.
param)

Implements org.bouncycastle.crypto.ec.ECPairTransform.init.

initialise the underlying EC ElGamal engine.

public ECPair

Returns:

returns a new ECPair representing the result of the process.
transform(ECPair
the EC point to process.
cipherText)

Implements org.bouncycastle.crypto.ec.ECPairTransform.transform.

Transform an existing cipher text pair using the ElGamal algorithm.

Inherited from java.lang.Object:
cloneequalsfinalizegetClasshashCodenotifynotifyAlltoStringwaitwaitwait

Field Detail

kback to summary
private BigInteger k
keyback to summary
private ECPublicKeyParameters key

Constructor Detail

ECFixedTransformback to summary
public ECFixedTransform(BigInteger k)

Method Detail

createBasePointMultiplierback to summary
protected ECMultiplier createBasePointMultiplier()
getTransformValueback to summary
public BigInteger getTransformValue()

Implements org.bouncycastle.crypto.ec.ECPairFactorTransform.getTransformValue.

Return the last transform value used by the transform

Returns:BigInteger

a BigInteger representing k value.

initback to summary
public void init(CipherParameters param)

Implements org.bouncycastle.crypto.ec.ECPairTransform.init.

initialise the underlying EC ElGamal engine.

Parameters
param:CipherParameters

the necessary EC key parameters.

transformback to summary
public ECPair transform(ECPair cipherText)

Implements org.bouncycastle.crypto.ec.ECPairTransform.transform.

Transform an existing cipher text pair using the ElGamal algorithm.

Note

it is assumed this transform has been initialised with the same public key that was used to create the original cipher text.

Parameters
cipherText:ECPair

the EC point to process.

Returns:ECPair

returns a new ECPair representing the result of the process.