1 files changed, 117 insertions, 0 deletions
diff --git a/crypto/src/asn1/BEROctetStringGenerator.cs b/crypto/src/asn1/BEROctetStringGenerator.cs
new file mode 100644
index 000000000..7468a6b0b
--- /dev/null
+++ b/crypto/src/asn1/BEROctetStringGenerator.cs
@@ -0,0 +1,117 @@
+using System;
+using System.IO;
+
+using Org.BouncyCastle.Utilities.IO;
+
+namespace Org.BouncyCastle.Asn1
+{
+	public class BerOctetStringGenerator
+		: BerGenerator
+	{
+		public BerOctetStringGenerator(Stream outStream)
+			: base(outStream)
+		{
+			WriteBerHeader(Asn1Tags.Constructed | Asn1Tags.OctetString);
+		}
+
+		public BerOctetStringGenerator(
+			Stream	outStream,
+			int		tagNo,
+			bool	isExplicit)
+			: base(outStream, tagNo, isExplicit)
+		{
+			WriteBerHeader(Asn1Tags.Constructed | Asn1Tags.OctetString);
+		}
+
+		public Stream GetOctetOutputStream()
+		{
+			return GetOctetOutputStream(new byte[1000]); // limit for CER encoding.
+		}
+
+		public Stream GetOctetOutputStream(
+			int bufSize)
+		{
+			return bufSize < 1
+				?	GetOctetOutputStream()
+				:	GetOctetOutputStream(new byte[bufSize]);
+		}
+
+		public Stream GetOctetOutputStream(
+			byte[] buf)
+		{
+			return new BufferedBerOctetStream(this, buf);
+		}
+
+		private class BufferedBerOctetStream
+			: BaseOutputStream
+		{
+			private byte[] _buf;
+			private int    _off;
+			private readonly BerOctetStringGenerator _gen;
+			private readonly DerOutputStream _derOut;
+
+			internal BufferedBerOctetStream(
+				BerOctetStringGenerator	gen,
+				byte[]					buf)
+			{
+				_gen = gen;
+				_buf = buf;
+				_off = 0;
+				_derOut = new DerOutputStream(_gen.Out);
+			}
+
+			public override void WriteByte(
+				byte b)
+			{
+				_buf[_off++] = b;
+
+				if (_off == _buf.Length)
+				{
+					DerOctetString.Encode(_derOut, _buf, 0, _off);
+					_off = 0;
+				}
+			}
+
+			public override void Write(
+				byte[] buf,
+				int    offset,
+				int    len)
+			{
+				while (len > 0)
+				{
+					int numToCopy = System.Math.Min(len, _buf.Length - _off);
+
+					if (numToCopy == _buf.Length)
+					{
+						DerOctetString.Encode(_derOut, buf, offset, numToCopy);
+					}
+					else
+					{
+						Array.Copy(buf, offset, _buf, _off, numToCopy);
+
+						_off += numToCopy;
+						if (_off < _buf.Length)
+							break;
+
+						DerOctetString.Encode(_derOut, _buf, 0, _off);
+						_off = 0;
+					}
+
+					offset += numToCopy;
+					len -= numToCopy;
+				}
+			}
+
+			public override void Close()
+			{
+				if (_off != 0)
+				{
+					DerOctetString.Encode(_derOut, _buf, 0, _off);
+				}
+
+				_gen.WriteBerEnd();
+				base.Close();
+			}
+		}
+	}
+}