1 files changed, 108 insertions, 0 deletions
diff --git a/crypto/src/asn1/DerSet.cs b/crypto/src/asn1/DerSet.cs
new file mode 100644
index 000000000..c66dde8c7
--- /dev/null
+++ b/crypto/src/asn1/DerSet.cs
@@ -0,0 +1,108 @@
+using System.IO;
+
+namespace Org.BouncyCastle.Asn1
+{
+	/**
+	 * A Der encoded set object
+	 */
+	public class DerSet
+		: Asn1Set
+	{
+		public static readonly DerSet Empty = new DerSet();
+
+		public static DerSet FromVector(
+			Asn1EncodableVector v)
+		{
+			return v.Count < 1 ? Empty : new DerSet(v);
+		}
+
+		internal static DerSet FromVector(
+			Asn1EncodableVector	v,
+			bool				needsSorting)
+		{
+			return v.Count < 1 ? Empty : new DerSet(v, needsSorting);
+		}
+
+		/**
+		 * create an empty set
+		 */
+		public DerSet()
+			: base(0)
+		{
+		}
+
+		/**
+		 * @param obj - a single object that makes up the set.
+		 */
+		public DerSet(
+			Asn1Encodable obj)
+			: base(1)
+		{
+			AddObject(obj);
+		}
+
+		public DerSet(
+			params Asn1Encodable[] v)
+			: base(v.Length)
+		{
+			foreach (Asn1Encodable o in v)
+			{
+				AddObject(o);
+			}
+
+			Sort();
+		}
+
+		/**
+		 * @param v - a vector of objects making up the set.
+		 */
+		public DerSet(
+			Asn1EncodableVector v)
+			: this(v, true)
+		{
+		}
+
+		internal DerSet(
+			Asn1EncodableVector	v,
+			bool				needsSorting)
+			: base(v.Count)
+		{
+			foreach (Asn1Encodable o in v)
+			{
+				AddObject(o);
+			}
+
+			if (needsSorting)
+			{
+				Sort();
+			}
+		}
+
+		/*
+		 * A note on the implementation:
+		 * <p>
+		 * As Der requires the constructed, definite-length model to
+		 * be used for structured types, this varies slightly from the
+		 * ASN.1 descriptions given. Rather than just outputing Set,
+		 * we also have to specify Constructed, and the objects length.
+		 */
+		internal override void Encode(
+			DerOutputStream derOut)
+		{
+			// TODO Intermediate buffer could be avoided if we could calculate expected length
+			MemoryStream bOut = new MemoryStream();
+			DerOutputStream dOut = new DerOutputStream(bOut);
+
+			foreach (Asn1Encodable obj in this)
+			{
+				dOut.WriteObject(obj);
+			}
+
+			dOut.Close();
+
+			byte[] bytes = bOut.ToArray();
+
+			derOut.WriteEncoded(Asn1Tags.Set | Asn1Tags.Constructed, bytes);
+		}
+	}
+}