Initial Commit

iTechSharp/srcbc/asn1/DerApplicationSpecific.cs

@@ -0,0 +1,150 @@
+using System;
+using System.IO;
+
+using Org.BouncyCastle.Utilities;
+
+namespace Org.BouncyCastle.Asn1
+{
+    /**
+     * Base class for an application specific object
+     */
+    public class DerApplicationSpecific
+        : Asn1Object
+    {
+		private readonly bool	isConstructed;
+        private readonly int	tag;
+        private readonly byte[]	octets;
+
+		internal DerApplicationSpecific(
+			bool	isConstructed,
+			int		tag,
+			byte[]	octets)
+		{
+			this.isConstructed = isConstructed;
+			this.tag = tag;
+			this.octets = octets;
+		}
+
+		public DerApplicationSpecific(
+            int		tag,
+            byte[]	octets)
+			: this(false, tag, octets)
+        {
+        }
+
+		public DerApplicationSpecific(
+			int				tag, 
+			Asn1Encodable	obj) 
+			: this(true, tag, obj)
+		{
+		}
+
+		public DerApplicationSpecific(
+			bool			isExplicit,
+			int				tag,
+			Asn1Encodable	obj)
+		{
+			if (tag >= 0x1f)
+				throw new IOException("unsupported tag number");
+
+			byte[] data = obj.GetDerEncoded();
+
+			this.isConstructed = isExplicit;
+			this.tag = tag;
+
+			if (isExplicit)
+			{
+				this.octets = data;
+			}
+			else
+			{
+				int lenBytes = GetLengthOfLength(data);
+				byte[] tmp = new byte[data.Length - lenBytes];
+				Array.Copy(data, lenBytes, tmp, 0, tmp.Length);
+				this.octets = tmp;
+			}
+		}
+
+		private int GetLengthOfLength(
+			byte[] data)
+		{
+			int count = 2;	// TODO: assumes only a 1 byte tag number
+
+			while((data[count - 1] & 0x80) != 0)
+			{
+				count++;
+			}
+
+			return count;
+		}
+
+		public bool IsConstructed()
+        {
+			return isConstructed;
+        }
+
+		public byte[] GetContents()
+        {
+            return octets;
+        }
+
+		public int ApplicationTag
+        {
+            get { return tag; }
+        }
+
+		public Asn1Object GetObject()
+        {
+			return FromByteArray(GetContents());
+		}
+
+		/**
+		 * Return the enclosed object assuming implicit tagging.
+		 *
+		 * @param derTagNo the type tag that should be applied to the object's contents.
+		 * @return  the resulting object
+		 * @throws IOException if reconstruction fails.
+		 */
+		public Asn1Object GetObject(
+			int derTagNo)
+		{
+			if (tag >= 0x1f)
+				throw new IOException("unsupported tag number");
+
+			byte[] tmp = this.GetEncoded();
+			tmp[0] = (byte) derTagNo;
+
+			return FromByteArray(tmp);;
+		}
+
+		internal override void Encode(
+			DerOutputStream derOut)
+        {
+			int classBits = Asn1Tags.Application;
+			if (isConstructed)
+			{
+				classBits |= Asn1Tags.Constructed; 
+			}
+
+			derOut.WriteEncoded(classBits, tag, octets);
+		}
+
+		protected override bool Asn1Equals(
+			Asn1Object asn1Object)
+        {
+			DerApplicationSpecific other = asn1Object as DerApplicationSpecific;
+
+			if (other == null)
+				return false;
+
+			return this.isConstructed == other.isConstructed
+				&& this.tag == other.tag
+				&& Arrays.AreEqual(this.octets, other.octets);
+        }
+
+		protected override int Asn1GetHashCode()
+		{
+			return isConstructed.GetHashCode() ^ tag.GetHashCode() ^ Arrays.GetHashCode(octets);
+        }
+    }
+}