public void TestIsSafeElementForNeutralElementCofactorOne()
{
var groupAlgebra = new MultiplicativeGroupAlgebra(BigPrime.CreateWithoutChecks(11), BigPrime.CreateWithoutChecks(10), 2);
Assert.That(groupAlgebra.IsPotentialElement(groupAlgebra.NeutralElement));
Assert.That(!groupAlgebra.IsSafeElement(groupAlgebra.NeutralElement));
}
public void TestComputeSecurityLevel()
{
var mod = BigPrime.CreateWithoutChecks(BigInteger.One << 2047);
Assert.AreEqual(115, MultiplicativeGroupAlgebra.ComputeSecurityLevel(mod, mod));
var smallOrder = BigPrime.CreateWithoutChecks(new BigInteger(4));
Assert.AreEqual(2 * NumberLength.GetLength(smallOrder).InBits, MultiplicativeGroupAlgebra.ComputeSecurityLevel(mod, smallOrder));
}
public void TestEqualsFalseForOtherAlgebra()
{
var otherAlgebra = new MultiplicativeGroupAlgebra(
BigPrime.CreateWithoutChecks(2 * 53 + 1),
BigPrime.CreateWithoutChecks(53),
4
);
Assert.IsFalse(groupAlgebra !.Equals(otherAlgebra));
}
public void TestComputePrimeLengthForSecurityLevel()
{
// dominated by NFS
var l = MultiplicativeGroupAlgebra.ComputePrimeLengthForSecurityLevel(100);
var p = BigPrime.CreateWithoutChecks(BigInteger.One << (l.InBits - 1));
var s = MultiplicativeGroupAlgebra.ComputeSecurityLevel(p, p);
Assert.AreEqual(100, s);
// dominated by Pollard Rho
l = MultiplicativeGroupAlgebra.ComputePrimeLengthForSecurityLevel(1);
Assert.AreEqual(2, l.InBits);
}