1 files changed, 117 insertions, 0 deletions
diff --git a/crypto/src/asn1/DerInteger.cs b/crypto/src/asn1/DerInteger.cs
new file mode 100644
index 000000000..eb0614515
--- /dev/null
+++ b/crypto/src/asn1/DerInteger.cs
@@ -0,0 +1,117 @@
+using System;
+
+using Org.BouncyCastle.Math;
+using Org.BouncyCastle.Utilities;
+
+namespace Org.BouncyCastle.Asn1
+{
+    public class DerInteger
+        : Asn1Object
+    {
+        private readonly byte[] bytes;
+
+        /**
+         * return an integer from the passed in object
+         *
+         * @exception ArgumentException if the object cannot be converted.
+         */
+        public static DerInteger GetInstance(
+            object obj)
+        {
+            if (obj == null || obj is DerInteger)
+            {
+                return (DerInteger)obj;
+            }
+
+			throw new ArgumentException("illegal object in GetInstance: " + obj.GetType().Name);
+        }
+
+        /**
+         * return an Integer from a tagged object.
+         *
+         * @param obj the tagged object holding the object we want
+         * @param isExplicit true if the object is meant to be explicitly
+         *              tagged false otherwise.
+         * @exception ArgumentException if the tagged object cannot
+         *               be converted.
+         */
+        public static DerInteger GetInstance(
+            Asn1TaggedObject	obj,
+            bool				isExplicit)
+        {
+            if (obj == null)
+                throw new ArgumentNullException("obj");
+
+			Asn1Object o = obj.GetObject();
+
+			if (isExplicit || o is DerInteger)
+			{
+				return GetInstance(o);
+			}
+
+			return new DerInteger(Asn1OctetString.GetInstance(o).GetOctets());
+        }
+
+		public DerInteger(
+            int value)
+        {
+            bytes = BigInteger.ValueOf(value).ToByteArray();
+        }
+
+		public DerInteger(
+            BigInteger value)
+        {
+            if (value == null)
+                throw new ArgumentNullException("value");
+
+			bytes = value.ToByteArray();
+        }
+
+		public DerInteger(
+            byte[] bytes)
+        {
+            this.bytes = bytes;
+        }
+
+		public BigInteger Value
+        {
+            get { return new BigInteger(bytes); }
+        }
+
+		/**
+         * in some cases positive values Get crammed into a space,
+         * that's not quite big enough...
+         */
+        public BigInteger PositiveValue
+        {
+            get { return new BigInteger(1, bytes); }
+        }
+
+        internal override void Encode(
+            DerOutputStream derOut)
+        {
+            derOut.WriteEncoded(Asn1Tags.Integer, bytes);
+        }
+
+		protected override int Asn1GetHashCode()
+		{
+			return Arrays.GetHashCode(bytes);
+        }
+
+		protected override bool Asn1Equals(
+			Asn1Object asn1Object)
+		{
+			DerInteger other = asn1Object as DerInteger;
+
+			if (other == null)
+				return false;
+
+			return Arrays.AreEqual(this.bytes, other.bytes);
+        }
+
+		public override string ToString()
+		{
+			return Value.ToString();
+		}
+	}
+}