private FpPoint MakePoint()
{
var rng = new SecureRandom();
var phe = new PheCrypto();
var swu = new Swu(phe.Curve.Q, phe.Curve.B.ToBigInteger());
var random = new byte[Swu.PointHashLen];
rng.NextBytes(random);
var(x, y) = swu.HashToPoint(random);
var xField = phe.Curve.FromBigInteger(x);
var yField = phe.Curve.FromBigInteger(y);
var ecpoint = phe.Curve.CreatePoint(x, y);
return((FpPoint)ecpoint);
}
public void TestPoint_Encoding()
{
var rng = new SecureRandom();
var phe = new PheCrypto();
var swu = new Swu(phe.Curve.Q, phe.Curve.B.ToBigInteger());
var random = new byte[Swu.PointHashLen];
rng.NextBytes(random);
var(x, y) = swu.HashToPoint(random);
var xField = phe.Curve.FromBigInteger(x);
var yField = phe.Curve.FromBigInteger(y);
var ecpoint = phe.Curve.CreatePoint(x, y);
var encoded = ecpoint.GetEncoded();
var decoded = phe.Curve.DecodePoint(encoded);
Assert.Equal(ecpoint, decoded);
}
public void Should_GeneratePointOnCurve_When_RandomHashesArePassed()
{
var curveParams = NistNamedCurves.GetByName("P-256");
var swu = new Swu(((FpCurve)curveParams.Curve).Q, curveParams.Curve.B.ToBigInteger());
var rng = new SecureRandom();
var sha = new Sha512tDigest(256);
var random = new byte[32];
for (int i = 0; i <= 10000; i++)
{
var hash = new byte[32];
rng.NextBytes(random);
sha.BlockUpdate(random, 0, random.Length);
sha.DoFinal(hash, 0);
var(x, y) = swu.HashToPoint(hash);
Assert.True(curveParams.Curve.CreatePoint(x, y).IsValid());
sha.Reset();
}
}