Package org.bouncycastle.crypto.hash2curve.impl

Class Elligator2MapToCurve

  • All Implemented Interfaces:
    MapToCurve
    public class Elligator2MapToCurve
extends java.lang.Object
implements MapToCurve
    Implements the Elligator 2 Map to curve according to section 6.7.1 of RFC 9380 This is the straight-line implementation optimized for Montgomery curves as defined in section F.3.

    • Constructor Summary

      Constructors 
      Constructor Description
      Elligator2MapToCurve​(ECCurve curve, java.math.BigInteger z, java.math.BigInteger J, java.math.BigInteger K)
      Constructs an Elligator2MapToCurve instance using the provided elliptic curve parameters and constants.

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      ECPoint process​(java.math.BigInteger u)
      Processes the given input value to map it to an elliptic curve point using the Elligator 2 algorithm, optimized for Montgomery curves.

      • Methods inherited from class java.lang.Object

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

    • Constructor Detail

      • Elligator2MapToCurve

        public Elligator2MapToCurve​(ECCurve curve,
                            java.math.BigInteger z,
                            java.math.BigInteger J,
                            java.math.BigInteger K)
        Constructs an Elligator2MapToCurve instance using the provided elliptic curve parameters and constants.
        Parameters:
        curve - the elliptic curve (ECCurve) to which the input values will be mapped
        z - a non-square element of the elliptic curve field
        J - the Montgomery curve equation A value (Named J in RFC 9380)
        K - the Montgomery curve equation B value (Named K in RFC 9380)

    • 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 Elligator 2 algorithm, optimized for Montgomery curves. This implementation adheres to the specifications outlined in RFC 9380, section 6.7.1, and section F.3 for efficient computation.
        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