kz.gamma.hardware.crypto.software.ec
Class WTauNafMultiplier

java.lang.Object
  kz.gamma.hardware.crypto.software.ec.WTauNafMultiplier

All Implemented Interfaces:

ECMultiplier

 class WTauNafMultiplier
extends java.lang.Object
implements ECMultiplier

Class implementing the WTNAF (Window τ-adic Non-Adjacent Form) algorithm.

Constructor Summary

WTauNafMultiplier()

Method Summary

ECPoint	multiply(ECPoint point, java.math.BigInteger k, PreCompInfo preCompInfo) Multiplies a ECPoint.F2m by k using the reduced τ-adic NAF (RTNAF) method.
private static ECPoint.F2m	multiplyFromWTnaf(ECPoint.F2m p, byte[] u, PreCompInfo preCompInfo) Multiplies a ECPoint.F2m by an element λ of Z[τ] using the window τ-adic NAF (TNAF) method, given the WTNAF of λ.
private ECPoint.F2m	multiplyWTnaf(ECPoint.F2m p, ZTauElement lambda, PreCompInfo preCompInfo, byte a, byte mu) Multiplies a ECPoint.F2m by an element λ of Z[τ] using the τ-adic NAF (TNAF) method.

Methods inherited from class java.lang.Object

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

Constructor Detail

WTauNafMultiplier

WTauNafMultiplier()

Method Detail

multiply

public ECPoint multiply(ECPoint point,
                        java.math.BigInteger k,
                        PreCompInfo preCompInfo)

Multiplies a ECPoint.F2m by k using the reduced τ-adic NAF (RTNAF) method.

Specified by:

multiply in interface ECMultiplier

Parameters:

p - The ECPoint.F2m to multiply.

k - The integer by which to multiply k.

Returns:

p multiplied by k.

multiplyWTnaf

private ECPoint.F2m multiplyWTnaf(ECPoint.F2m p,
                                  ZTauElement lambda,
                                  PreCompInfo preCompInfo,
                                  byte a,
                                  byte mu)

Multiplies a ECPoint.F2m by an element λ of Z[τ] using the τ-adic NAF (TNAF) method.

Parameters:

p - The ECPoint.F2m to multiply.

lambda - The element λ of Z[τ] of which to compute the [τ]-adic NAF.

Returns:

p multiplied by λ.

multiplyFromWTnaf

private static ECPoint.F2m multiplyFromWTnaf(ECPoint.F2m p,
                                             byte[] u,
                                             PreCompInfo preCompInfo)

Multiplies a ECPoint.F2m by an element λ of Z[τ] using the window τ-adic NAF (TNAF) method, given the WTNAF of λ.

Parameters:

p - The ECPoint.F2m to multiply.

u - The the WTNAF of λ..

Returns:

λ * p