init commit

output/Libraries/BouncyCastle.Crypto/Org/BouncyCastle/Math/EC/FpCurve.cs

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+using System;
+
+namespace Org.BouncyCastle.Math.EC;
+
+public class FpCurve : AbstractFpCurve
+{
+	private const int FP_DEFAULT_COORDS = 4;
+
+	protected readonly BigInteger m_q;
+
+	protected readonly BigInteger m_r;
+
+	protected readonly FpPoint m_infinity;
+
+	public virtual BigInteger Q => m_q;
+
+	public override ECPoint Infinity => m_infinity;
+
+	public override int FieldSize => m_q.BitLength;
+
+	[Obsolete("Use constructor taking order/cofactor")]
+	public FpCurve(BigInteger q, BigInteger a, BigInteger b)
+		: this(q, a, b, null, null)
+	{
+	}
+
+	public FpCurve(BigInteger q, BigInteger a, BigInteger b, BigInteger order, BigInteger cofactor)
+		: base(q)
+	{
+		m_q = q;
+		m_r = FpFieldElement.CalculateResidue(q);
+		m_infinity = new FpPoint(this, null, null, withCompression: false);
+		m_a = FromBigInteger(a);
+		m_b = FromBigInteger(b);
+		m_order = order;
+		m_cofactor = cofactor;
+		m_coord = 4;
+	}
+
+	[Obsolete("Use constructor taking order/cofactor")]
+	protected FpCurve(BigInteger q, BigInteger r, ECFieldElement a, ECFieldElement b)
+		: this(q, r, a, b, null, null)
+	{
+	}
+
+	protected FpCurve(BigInteger q, BigInteger r, ECFieldElement a, ECFieldElement b, BigInteger order, BigInteger cofactor)
+		: base(q)
+	{
+		m_q = q;
+		m_r = r;
+		m_infinity = new FpPoint(this, null, null, withCompression: false);
+		m_a = a;
+		m_b = b;
+		m_order = order;
+		m_cofactor = cofactor;
+		m_coord = 4;
+	}
+
+	protected override ECCurve CloneCurve()
+	{
+		return new FpCurve(m_q, m_r, m_a, m_b, m_order, m_cofactor);
+	}
+
+	public override bool SupportsCoordinateSystem(int coord)
+	{
+		switch (coord)
+		{
+		case 0:
+		case 1:
+		case 2:
+		case 4:
+			return true;
+		default:
+			return false;
+		}
+	}
+
+	public override ECFieldElement FromBigInteger(BigInteger x)
+	{
+		return new FpFieldElement(m_q, m_r, x);
+	}
+
+	protected internal override ECPoint CreateRawPoint(ECFieldElement x, ECFieldElement y, bool withCompression)
+	{
+		return new FpPoint(this, x, y, withCompression);
+	}
+
+	protected internal override ECPoint CreateRawPoint(ECFieldElement x, ECFieldElement y, ECFieldElement[] zs, bool withCompression)
+	{
+		return new FpPoint(this, x, y, zs, withCompression);
+	}
+
+	public override ECPoint ImportPoint(ECPoint p)
+	{
+		if (this != p.Curve && CoordinateSystem == 2 && !p.IsInfinity)
+		{
+			switch (p.Curve.CoordinateSystem)
+			{
+			case 2:
+			case 3:
+			case 4:
+				return new FpPoint(this, FromBigInteger(p.RawXCoord.ToBigInteger()), FromBigInteger(p.RawYCoord.ToBigInteger()), new ECFieldElement[1] { FromBigInteger(p.GetZCoord(0).ToBigInteger()) }, p.IsCompressed);
+			}
+		}
+		return base.ImportPoint(p);
+	}
+}