diff --git a/crypto/src/math/ec/custom/djb/Curve25519.cs b/crypto/src/math/ec/custom/djb/Curve25519.cs
index 3dbdac051..712b68f29 100644
--- a/crypto/src/math/ec/custom/djb/Curve25519.cs
+++ b/crypto/src/math/ec/custom/djb/Curve25519.cs
@@ -1,13 +1,12 @@
using System;
using Org.BouncyCastle.Math.EC.Custom.Sec;
-using Org.BouncyCastle.Math.Field;
using Org.BouncyCastle.Utilities.Encoders;
namespace Org.BouncyCastle.Math.EC.Custom.Djb
{
internal class Curve25519
- : ECCurve
+ : AbstractFpCurve
{
public static readonly BigInteger q = Nat256.ToBigInteger(Curve25519Field.P);
@@ -16,7 +15,7 @@ namespace Org.BouncyCastle.Math.EC.Custom.Djb
protected readonly Curve25519Point m_infinity;
public Curve25519()
- : base(FiniteFields.GetPrimeField(q))
+ : base(q)
{
this.m_infinity = new Curve25519Point(this, null, null);
@@ -74,27 +73,5 @@ namespace Org.BouncyCastle.Math.EC.Custom.Djb
{
return new Curve25519Point(this, x, y, zs, withCompression);
}
-
- protected override ECPoint DecompressPoint(int yTilde, BigInteger X1)
- {
- ECFieldElement x = FromBigInteger(X1);
- ECFieldElement alpha = x.Square().Add(A).Multiply(x).Add(B);
- ECFieldElement beta = alpha.Sqrt();
-
- //
- // if we can't find a sqrt we haven't got a point on the
- // curve - run!
- //
- if (beta == null)
- throw new ArithmeticException("Invalid point compression");
-
- if (beta.TestBitZero() != (yTilde == 1))
- {
- // Use the other root
- beta = beta.Negate();
- }
-
- return new Curve25519Point(this, x, beta, true);
- }
}
}
diff --git a/crypto/src/math/ec/custom/djb/Curve25519Point.cs b/crypto/src/math/ec/custom/djb/Curve25519Point.cs
index f3da59d16..bfec1d11d 100644
--- a/crypto/src/math/ec/custom/djb/Curve25519Point.cs
+++ b/crypto/src/math/ec/custom/djb/Curve25519Point.cs
@@ -5,7 +5,7 @@ using Org.BouncyCastle.Math.EC.Custom.Sec;
namespace Org.BouncyCastle.Math.EC.Custom.Djb
{
internal class Curve25519Point
- : ECPointBase
+ : AbstractFpPoint
{
/**
* Create a point which encodes with point compression.
@@ -48,11 +48,6 @@ namespace Org.BouncyCastle.Math.EC.Custom.Djb
return new Curve25519Point(null, AffineXCoord, AffineYCoord);
}
- protected internal override bool CompressionYTilde
- {
- get { return this.AffineYCoord.TestBitZero(); }
- }
-
public override ECFieldElement GetZCoord(int index)
{
if (index == 1)
@@ -224,14 +219,6 @@ namespace Org.BouncyCastle.Math.EC.Custom.Djb
return TwiceJacobianModified(false).Add(this);
}
- public override ECPoint Subtract(ECPoint b)
- {
- if (b.IsInfinity)
- return this;
-
- return Add(b.Negate());
- }
-
public override ECPoint Negate()
{
if (IsInfinity)
|
