org.bouncycastle.crypto.hash2curve.impl

Class SimplifiedShallueVanDeWoestijneMapToCurve

java.lang.Object

org.bouncycastle.crypto.hash2curve.impl.SimplifiedShallueVanDeWoestijneMapToCurve

All Implemented Interfaces:

MapToCurve

public class SimplifiedShallueVanDeWoestijneMapToCurve
extends java.lang.Object
implements MapToCurve

Implements the Simplified Shallue van de Woestijne Map to curve according to section 6.6.2 of RFC 9380 This is the straight-line implementation optimized for Weierstrass curves as defined in section F.2.

Constructor Summary

Constructors

Constructor and Description
SimplifiedShallueVanDeWoestijneMapToCurve(ECCurve curve, java.math.BigInteger z) Constructs an instance of the SimplifiedShallueVanDeWoestijneMapToCurve mapping mechanism for mapping values onto a Weierstrass elliptic curve.

Method Summary

Modifier and Type	Method and Description
ECPoint	process(java.math.BigInteger u) Processes the given input value to map it to an elliptic curve point using the Shallue-van de Woestijne algorithm, optimized for Weierstrass curves.

Methods inherited from class java.lang.Object

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

Constructor Detail

SimplifiedShallueVanDeWoestijneMapToCurve

public SimplifiedShallueVanDeWoestijneMapToCurve(ECCurve curve,
                                                 java.math.BigInteger z)

Constructs an instance of the SimplifiedShallueVanDeWoestijneMapToCurve mapping mechanism for mapping values onto a Weierstrass elliptic curve. This implementation is based on section 6.6.2 of RFC 9380 and optimizations defined in section F.2.

Parameters:

curve - the elliptic curve to which the mapping will be applied; must conform to the Weierstrass form

z - a non-zero constant value used as a parameter in the mapping algorithm

Method Detail

process

public ECPoint process(java.math.BigInteger u)

Processes the given input value to map it to an elliptic curve point using the Shallue-van de Woestijne algorithm, optimized for Weierstrass curves. This implementation adheres to the specifications outlined in RFC 9380, section 6.6.2, and section F.2 for efficient computation.

The method computes the x and y coordinates for the point on the elliptic curve, using modular arithmetic and auxiliary functions for square root computation and conditional assignments.

Specified by:

process in interface MapToCurve

Parameters:

u - the input value to be mapped to a point on the elliptic curve

Returns:

the computed point on the elliptic curve represented as an ECPoint