init commit

output/Libraries/BouncyCastle.Crypto/Org/BouncyCastle/Math/EC/F2mCurve.cs

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+using System;
+using Org.BouncyCastle.Math.EC.Multiplier;
+
+namespace Org.BouncyCastle.Math.EC;
+
+public class F2mCurve : AbstractF2mCurve
+{
+	private class DefaultF2mLookupTable : ECLookupTable
+	{
+		private readonly F2mCurve m_outer;
+
+		private readonly long[] m_table;
+
+		private readonly int m_size;
+
+		public virtual int Size => m_size;
+
+		internal DefaultF2mLookupTable(F2mCurve outer, long[] table, int size)
+		{
+			m_outer = outer;
+			m_table = table;
+			m_size = size;
+		}
+
+		public virtual ECPoint Lookup(int index)
+		{
+			int m = m_outer.m;
+			int[] ks = (m_outer.IsTrinomial() ? new int[1] { m_outer.k1 } : new int[3] { m_outer.k1, m_outer.k2, m_outer.k3 });
+			int num = (m_outer.m + 63) / 64;
+			long[] array = new long[num];
+			long[] array2 = new long[num];
+			int num2 = 0;
+			for (int i = 0; i < m_size; i++)
+			{
+				long num3 = (i ^ index) - 1 >> 31;
+				for (int j = 0; j < num; j++)
+				{
+					long[] array4;
+					long[] array3 = (array4 = array);
+					int num4 = j;
+					nint num5 = num4;
+					array3[num4] = array4[num5] ^ (m_table[num2 + j] & num3);
+					long[] array5 = (array4 = array2);
+					int num6 = j;
+					num5 = num6;
+					array5[num6] = array4[num5] ^ (m_table[num2 + num + j] & num3);
+				}
+				num2 += num * 2;
+			}
+			ECFieldElement x = new F2mFieldElement(m, ks, new LongArray(array));
+			ECFieldElement y = new F2mFieldElement(m, ks, new LongArray(array2));
+			return m_outer.CreateRawPoint(x, y, withCompression: false);
+		}
+	}
+
+	private const int F2M_DEFAULT_COORDS = 6;
+
+	private readonly int m;
+
+	private readonly int k1;
+
+	private readonly int k2;
+
+	private readonly int k3;
+
+	protected readonly F2mPoint m_infinity;
+
+	public override int FieldSize => m;
+
+	public override ECPoint Infinity => m_infinity;
+
+	public int M => m;
+
+	public int K1 => k1;
+
+	public int K2 => k2;
+
+	public int K3 => k3;
+
+	[Obsolete("Use constructor taking order/cofactor")]
+	public F2mCurve(int m, int k, BigInteger a, BigInteger b)
+		: this(m, k, 0, 0, a, b, null, null)
+	{
+	}
+
+	public F2mCurve(int m, int k, BigInteger a, BigInteger b, BigInteger order, BigInteger cofactor)
+		: this(m, k, 0, 0, a, b, order, cofactor)
+	{
+	}
+
+	[Obsolete("Use constructor taking order/cofactor")]
+	public F2mCurve(int m, int k1, int k2, int k3, BigInteger a, BigInteger b)
+		: this(m, k1, k2, k3, a, b, null, null)
+	{
+	}
+
+	public F2mCurve(int m, int k1, int k2, int k3, BigInteger a, BigInteger b, BigInteger order, BigInteger cofactor)
+		: base(m, k1, k2, k3)
+	{
+		this.m = m;
+		this.k1 = k1;
+		this.k2 = k2;
+		this.k3 = k3;
+		m_order = order;
+		m_cofactor = cofactor;
+		m_infinity = new F2mPoint(this, null, null, withCompression: false);
+		if (k1 == 0)
+		{
+			throw new ArgumentException("k1 must be > 0");
+		}
+		if (k2 == 0)
+		{
+			if (k3 != 0)
+			{
+				throw new ArgumentException("k3 must be 0 if k2 == 0");
+			}
+		}
+		else
+		{
+			if (k2 <= k1)
+			{
+				throw new ArgumentException("k2 must be > k1");
+			}
+			if (k3 <= k2)
+			{
+				throw new ArgumentException("k3 must be > k2");
+			}
+		}
+		m_a = FromBigInteger(a);
+		m_b = FromBigInteger(b);
+		m_coord = 6;
+	}
+
+	protected F2mCurve(int m, int k1, int k2, int k3, ECFieldElement a, ECFieldElement b, BigInteger order, BigInteger cofactor)
+		: base(m, k1, k2, k3)
+	{
+		this.m = m;
+		this.k1 = k1;
+		this.k2 = k2;
+		this.k3 = k3;
+		m_order = order;
+		m_cofactor = cofactor;
+		m_infinity = new F2mPoint(this, null, null, withCompression: false);
+		m_a = a;
+		m_b = b;
+		m_coord = 6;
+	}
+
+	protected override ECCurve CloneCurve()
+	{
+		return new F2mCurve(m, k1, k2, k3, m_a, m_b, m_order, m_cofactor);
+	}
+
+	public override bool SupportsCoordinateSystem(int coord)
+	{
+		switch (coord)
+		{
+		case 0:
+		case 1:
+		case 6:
+			return true;
+		default:
+			return false;
+		}
+	}
+
+	protected override ECMultiplier CreateDefaultMultiplier()
+	{
+		if (IsKoblitz)
+		{
+			return new WTauNafMultiplier();
+		}
+		return base.CreateDefaultMultiplier();
+	}
+
+	public override ECFieldElement FromBigInteger(BigInteger x)
+	{
+		return new F2mFieldElement(m, k1, k2, k3, x);
+	}
+
+	protected internal override ECPoint CreateRawPoint(ECFieldElement x, ECFieldElement y, bool withCompression)
+	{
+		return new F2mPoint(this, x, y, withCompression);
+	}
+
+	protected internal override ECPoint CreateRawPoint(ECFieldElement x, ECFieldElement y, ECFieldElement[] zs, bool withCompression)
+	{
+		return new F2mPoint(this, x, y, zs, withCompression);
+	}
+
+	public bool IsTrinomial()
+	{
+		if (k2 == 0)
+		{
+			return k3 == 0;
+		}
+		return false;
+	}
+
+	public override ECLookupTable CreateCacheSafeLookupTable(ECPoint[] points, int off, int len)
+	{
+		int num = (m + 63) / 64;
+		long[] array = new long[len * num * 2];
+		int num2 = 0;
+		for (int i = 0; i < len; i++)
+		{
+			ECPoint eCPoint = points[off + i];
+			((F2mFieldElement)eCPoint.RawXCoord).x.CopyTo(array, num2);
+			num2 += num;
+			((F2mFieldElement)eCPoint.RawYCoord).x.CopyTo(array, num2);
+			num2 += num;
+		}
+		return new DefaultF2mLookupTable(this, array, len);
+	}
+}