init commit

output/Libraries/BouncyCastle.Crypto/Org/BouncyCastle/Crypto/Signers/PlainDsaEncoding.cs

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+using System;
+using Org.BouncyCastle.Math;
+using Org.BouncyCastle.Utilities;
+
+namespace Org.BouncyCastle.Crypto.Signers;
+
+public class PlainDsaEncoding : IDsaEncoding
+{
+	public static readonly PlainDsaEncoding Instance = new PlainDsaEncoding();
+
+	public virtual BigInteger[] Decode(BigInteger n, byte[] encoding)
+	{
+		int unsignedByteLength = BigIntegers.GetUnsignedByteLength(n);
+		if (encoding.Length != unsignedByteLength * 2)
+		{
+			throw new ArgumentException("Encoding has incorrect length", "encoding");
+		}
+		return new BigInteger[2]
+		{
+			DecodeValue(n, encoding, 0, unsignedByteLength),
+			DecodeValue(n, encoding, unsignedByteLength, unsignedByteLength)
+		};
+	}
+
+	public virtual byte[] Encode(BigInteger n, BigInteger r, BigInteger s)
+	{
+		int unsignedByteLength = BigIntegers.GetUnsignedByteLength(n);
+		byte[] array = new byte[unsignedByteLength * 2];
+		EncodeValue(n, r, array, 0, unsignedByteLength);
+		EncodeValue(n, s, array, unsignedByteLength, unsignedByteLength);
+		return array;
+	}
+
+	protected virtual BigInteger CheckValue(BigInteger n, BigInteger x)
+	{
+		if (x.SignValue < 0 || x.CompareTo(n) >= 0)
+		{
+			throw new ArgumentException("Value out of range", "x");
+		}
+		return x;
+	}
+
+	protected virtual BigInteger DecodeValue(BigInteger n, byte[] buf, int off, int len)
+	{
+		return CheckValue(n, new BigInteger(1, buf, off, len));
+	}
+
+	protected virtual void EncodeValue(BigInteger n, BigInteger x, byte[] buf, int off, int len)
+	{
+		byte[] array = CheckValue(n, x).ToByteArrayUnsigned();
+		int num = System.Math.Max(0, array.Length - len);
+		int num2 = array.Length - num;
+		int num3 = len - num2;
+		Arrays.Fill(buf, off, off + num3, 0);
+		Array.Copy(array, num, buf, off + num3, num2);
+	}
+}