<PackageReference Include="BouncyCastle.Cryptography" Version="2.6.2" />

SecT239K1Curve

using Org.BouncyCastle.Math.EC.Multiplier; using Org.BouncyCastle.Math.Raw; using Org.BouncyCastle.Utilities.Encoders; namespace Org.BouncyCastle.Math.EC.Custom.Sec { internal class SecT239K1Curve : AbstractF2mCurve { private class SecT239K1LookupTable : AbstractECLookupTable { private readonly SecT239K1Curve m_outer; private readonly ulong[] m_table; private readonly int m_size; public override int Size => m_size; internal SecT239K1LookupTable(SecT239K1Curve outer, ulong[] table, int size) { m_outer = outer; m_table = table; m_size = size; } public override ECPoint Lookup(int index) { ulong[] array = Nat256.Create64(); ulong[] array2 = Nat256.Create64(); int num = 0; for (int i = 0; i < m_size; i++) { ulong num2 = (ulong)((i ^ index) - 1 >> 31); for (int j = 0; j < 4; j++) { array[j] ^= (m_table[num + j] & num2); array2[j] ^= (m_table[num + 4 + j] & num2); } num += 8; } return CreatePoint(array, array2); } public override ECPoint LookupVar(int index) { ulong[] array = Nat256.Create64(); ulong[] array2 = Nat256.Create64(); int num = index * 4 * 2; for (int i = 0; i < 4; i++) { array[i] = m_table[num + i]; array2[i] = m_table[num + 4 + i]; } return CreatePoint(array, array2); } private ECPoint CreatePoint(ulong[] x, ulong[] y) { return m_outer.CreateRawPoint(new SecT239FieldElement(x), new SecT239FieldElement(y), SECT239K1_AFFINE_ZS); } } private const int SECT239K1_DEFAULT_COORDS = 6; private const int SECT239K1_FE_LONGS = 4; private static readonly ECFieldElement[] SECT239K1_AFFINE_ZS = new ECFieldElement[1] { new SecT239FieldElement(BigInteger.One) }; protected readonly SecT239K1Point m_infinity; public override ECPoint Infinity => m_infinity; public override int FieldSize => 239; public override bool IsKoblitz => true; public virtual int M => 239; public virtual bool IsTrinomial => true; public virtual int K1 => 158; public virtual int K2 => 0; public virtual int K3 => 0; public SecT239K1Curve() : base(239, 158, 0, 0) { m_infinity = new SecT239K1Point(this, null, null); m_a = FromBigInteger(BigInteger.Zero); m_b = FromBigInteger(BigInteger.One); m_order = new BigInteger(1, Hex.DecodeStrict("2000000000000000000000000000005A79FEC67CB6E91F1C1DA800E478A5")); m_cofactor = BigInteger.ValueOf(4); m_coord = 6; } protected override ECCurve CloneCurve() { return new SecT239K1Curve(); } public override bool SupportsCoordinateSystem(int coord) { if (coord == 6) return true; return false; } protected override ECMultiplier CreateDefaultMultiplier() { return new WTauNafMultiplier(); } public override ECFieldElement FromBigInteger(BigInteger x) { return new SecT239FieldElement(x); } protected internal override ECPoint CreateRawPoint(ECFieldElement x, ECFieldElement y) { return new SecT239K1Point(this, x, y); } protected internal override ECPoint CreateRawPoint(ECFieldElement x, ECFieldElement y, ECFieldElement[] zs) { return new SecT239K1Point(this, x, y, zs); } public override ECLookupTable CreateCacheSafeLookupTable(ECPoint[] points, int off, int len) { ulong[] array = new ulong[len * 4 * 2]; int num = 0; for (int i = 0; i < len; i++) { ECPoint obj = points[off + i]; Nat256.Copy64(((SecT239FieldElement)obj.RawXCoord).x, 0, array, num); num += 4; Nat256.Copy64(((SecT239FieldElement)obj.RawYCoord).x, 0, array, num); num += 4; } return new SecT239K1LookupTable(this, array, len); } } }