init commit

output/Libraries/BouncyCastle.Crypto/Org/BouncyCastle/Asn1/DefiniteLengthInputStream.cs

@@ -0,0 +1,96 @@
+using System;
+using System.IO;
+using Org.BouncyCastle.Utilities.IO;
+
+namespace Org.BouncyCastle.Asn1;
+
+internal class DefiniteLengthInputStream : LimitedInputStream
+{
+	private static readonly byte[] EmptyBytes = new byte[0];
+
+	private readonly int _originalLength;
+
+	private int _remaining;
+
+	internal int Remaining => _remaining;
+
+	internal DefiniteLengthInputStream(Stream inStream, int length)
+		: base(inStream, length)
+	{
+		if (length < 0)
+		{
+			throw new ArgumentException("negative lengths not allowed", "length");
+		}
+		_originalLength = length;
+		_remaining = length;
+		if (length == 0)
+		{
+			SetParentEofDetect(on: true);
+		}
+	}
+
+	public override int ReadByte()
+	{
+		if (_remaining == 0)
+		{
+			return -1;
+		}
+		int num = _in.ReadByte();
+		if (num < 0)
+		{
+			throw new EndOfStreamException("DEF length " + _originalLength + " object truncated by " + _remaining);
+		}
+		if (--_remaining == 0)
+		{
+			SetParentEofDetect(on: true);
+		}
+		return num;
+	}
+
+	public override int Read(byte[] buf, int off, int len)
+	{
+		if (_remaining == 0)
+		{
+			return 0;
+		}
+		int count = System.Math.Min(len, _remaining);
+		int num = _in.Read(buf, off, count);
+		if (num < 1)
+		{
+			throw new EndOfStreamException("DEF length " + _originalLength + " object truncated by " + _remaining);
+		}
+		if ((_remaining -= num) == 0)
+		{
+			SetParentEofDetect(on: true);
+		}
+		return num;
+	}
+
+	internal void ReadAllIntoByteArray(byte[] buf)
+	{
+		if (_remaining != buf.Length)
+		{
+			throw new ArgumentException("buffer length not right for data");
+		}
+		if ((_remaining -= Streams.ReadFully(_in, buf)) != 0)
+		{
+			throw new EndOfStreamException("DEF length " + _originalLength + " object truncated by " + _remaining);
+		}
+		SetParentEofDetect(on: true);
+	}
+
+	internal byte[] ToArray()
+	{
+		if (_remaining == 0)
+		{
+			return EmptyBytes;
+		}
+		byte[] array = new byte[_remaining];
+		if ((_remaining -= Streams.ReadFully(_in, array)) != 0)
+		{
+			throw new EndOfStreamException("DEF length " + _originalLength + " object truncated by " + _remaining);
+		}
+		SetParentEofDetect(on: true);
+		return array;
+	}
+}