using System; namespace Renci.SshNet.Security.Org.BouncyCastle.Math.EC { internal abstract class AbstractFpPoint : ECPointBase { protected internal override bool CompressionYTilde => AffineYCoord.TestBitZero(); protected AbstractFpPoint(ECCurve curve, ECFieldElement x, ECFieldElement y, bool withCompression) : base(curve, x, y, withCompression) { } protected AbstractFpPoint(ECCurve curve, ECFieldElement x, ECFieldElement y, ECFieldElement[] zs, bool withCompression) : base(curve, x, y, zs, withCompression) { } protected override bool SatisfiesCurveEquation() { ECFieldElement rawXCoord = base.RawXCoord; ECFieldElement rawYCoord = base.RawYCoord; ECFieldElement eCFieldElement = Curve.A; ECFieldElement eCFieldElement2 = Curve.B; ECFieldElement eCFieldElement3 = rawYCoord.Square(); switch (CurveCoordinateSystem) { case 1: { ECFieldElement eCFieldElement6 = base.RawZCoords[0]; if (!eCFieldElement6.IsOne) { ECFieldElement b3 = eCFieldElement6.Square(); ECFieldElement b4 = eCFieldElement6.Multiply(b3); eCFieldElement3 = eCFieldElement3.Multiply(eCFieldElement6); eCFieldElement = eCFieldElement.Multiply(b3); eCFieldElement2 = eCFieldElement2.Multiply(b4); } break; } case 2: case 3: case 4: { ECFieldElement eCFieldElement4 = base.RawZCoords[0]; if (!eCFieldElement4.IsOne) { ECFieldElement eCFieldElement5 = eCFieldElement4.Square(); ECFieldElement b = eCFieldElement5.Square(); ECFieldElement b2 = eCFieldElement5.Multiply(b); eCFieldElement = eCFieldElement.Multiply(b); eCFieldElement2 = eCFieldElement2.Multiply(b2); } break; } default: throw new InvalidOperationException("unsupported coordinate system"); case 0: break; } ECFieldElement other = rawXCoord.Square().Add(eCFieldElement).Multiply(rawXCoord) .Add(eCFieldElement2); return eCFieldElement3.Equals(other); } public override ECPoint Subtract(ECPoint b) { if (b.IsInfinity) return this; return Add(b.Negate()); } } }