Package org.bouncycastle.pqc.math.linearalgebra

Class GF2nONBField

  • public class GF2nONBField
extends GF2nField
    This class implements the abstract class GF2nField for ONB representation. It computes the fieldpolynomial, multiplication matrix and one of its roots mONBRoot, (see for example Certicoms Whitepapers). GF2nField is used by GF2nONBElement which implements the elements of this field.
    See Also:
    GF2nField, GF2nONBElement

    • Constructor Detail

      • GF2nONBField

        public GF2nONBField​(int deg,
                    java.security.SecureRandom random)
             throws java.lang.RuntimeException
        constructs an instance of the finite field with 2deg elements and characteristic 2.
        Parameters:
        deg - -the extention degree of this field
        random - - a source of randomness for generating polynomials on the field.
        Throws:
        java.lang.RuntimeException

    • Method Detail

      • getRandomRoot

        protected GF2nElement getRandomRoot​(GF2Polynomial polynomial)
        Computes a random root of the given polynomial.
        Specified by:
        getRandomRoot in class GF2nField
        Parameters:
        polynomial - a polynomial
        Returns:
        a random root of the polynomial
        See Also:
        "P1363 A.5.6, p103f"

      • computeCOBMatrix

        protected void computeCOBMatrix​(GF2nField B1)
        Computes the change-of-basis matrix for basis conversion according to 1363. The result is stored in the lists fields and matrices.
        Specified by:
        computeCOBMatrix in class GF2nField
        Parameters:
        B1 - the GF2nField to convert to
        See Also:
        "P1363 A.7.3, p111ff"

      • computeFieldPolynomial

        protected void computeFieldPolynomial()
        Computes the field polynomial for a ONB according to IEEE 1363 A.7.2 (p110f).
        Specified by:
        computeFieldPolynomial in class GF2nField
        See Also:
        "P1363 A.7.2, p110f"