1 files changed, 41 insertions, 0 deletions
diff --git a/crypto/src/asn1/DerNull.cs b/crypto/src/asn1/DerNull.cs
new file mode 100644
index 000000000..a802f6486
--- /dev/null
+++ b/crypto/src/asn1/DerNull.cs
@@ -0,0 +1,41 @@
+using System;
+
+namespace Org.BouncyCastle.Asn1
+{
+	/**
+	 * A Null object.
+	 */
+	public class DerNull
+		: Asn1Null
+	{
+		public static readonly DerNull Instance = new DerNull(0);
+
+		byte[] zeroBytes = new byte[0];
+
+		[Obsolete("Use static Instance object")]
+		public DerNull()
+		{
+		}
+
+		protected internal DerNull(int dummy)
+		{
+		}
+
+		internal override void Encode(
+			DerOutputStream  derOut)
+		{
+			derOut.WriteEncoded(Asn1Tags.Null, zeroBytes);
+		}
+
+		protected override bool Asn1Equals(
+			Asn1Object asn1Object)
+		{
+			return asn1Object is DerNull;
+		}
+
+		protected override int Asn1GetHashCode()
+		{
+			return -1;
+		}
+	}
+}