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diff --git a/Emby.Server.Implementations/Cryptography/ASN1.cs b/Emby.Server.Implementations/Cryptography/ASN1.cs
new file mode 100644
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+++ b/Emby.Server.Implementations/Cryptography/ASN1.cs
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+//
+// ASN1.cs: Abstract Syntax Notation 1 - micro-parser and generator
+//
+// Authors:
+//	Sebastien Pouliot  <sebastien@ximian.com>
+//	Jesper Pedersen  <jep@itplus.dk>
+//
+// (C) 2002, 2003 Motus Technologies Inc. (http://www.motus.com)
+// Copyright (C) 2004 Novell, Inc (http://www.novell.com)
+// (C) 2004 IT+ A/S (http://www.itplus.dk)
+//
+// Permission is hereby granted, free of charge, to any person obtaining
+// a copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to
+// permit persons to whom the Software is furnished to do so, subject to
+// the following conditions:
+// 
+// The above copyright notice and this permission notice shall be
+// included in all copies or substantial portions of the Software.
+// 
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+//
+
+using System;
+using System.Collections;
+using System.IO;
+using System.Text;
+
+namespace Emby.Server.Core.Cryptography
+{
+
+	// References:
+	// a.	ITU ASN.1 standards (free download)
+	//	http://www.itu.int/ITU-T/studygroups/com17/languages/
+
+    public class ASN1 {
+
+		private byte m_nTag;
+		private byte[] m_aValue;
+		private ArrayList elist;
+
+		public ASN1 () : this (0x00, null) {}
+
+		public ASN1 (byte tag) : this (tag, null) {}
+
+		public ASN1 (byte tag, byte[] data) 
+		{
+			m_nTag = tag;
+			m_aValue = data;
+		}
+
+		public ASN1 (byte[] data) 
+		{
+			m_nTag = data [0];
+
+			int nLenLength = 0;
+			int nLength = data [1];
+
+			if (nLength > 0x80) {
+				// composed length
+				nLenLength = nLength - 0x80;
+				nLength = 0;
+				for (int i = 0; i < nLenLength; i++) {
+					nLength *= 256;
+					nLength += data [i + 2];
+				}
+			}
+			else if (nLength == 0x80) {
+				// undefined length encoding
+				throw new NotSupportedException ("Undefined length encoding.");
+			}
+
+			m_aValue = new byte [nLength];
+			Buffer.BlockCopy (data, (2 + nLenLength), m_aValue, 0, nLength);
+
+			if ((m_nTag & 0x20) == 0x20) {
+				int nStart = (2 + nLenLength);
+				Decode (data, ref nStart, data.Length);
+			}
+		}
+
+		public int Count {
+			get { 
+				if (elist == null)
+					return 0;
+				return elist.Count; 
+			}
+		}
+
+		public byte Tag {
+			get { return m_nTag; }
+		}
+
+		public int Length {
+			get { 
+				if (m_aValue != null)
+					return m_aValue.Length; 
+				else
+					return 0;
+			}
+		}
+
+		public byte[] Value {
+			get { 
+				if (m_aValue == null)
+					GetBytes ();
+				return (byte[]) m_aValue.Clone (); 
+			}
+			set { 
+				if (value != null)
+					m_aValue = (byte[]) value.Clone (); 
+			}
+		}
+
+		private bool CompareArray (byte[] array1, byte[] array2)
+		{
+			bool bResult = (array1.Length == array2.Length);
+			if (bResult) {
+				for (int i = 0; i < array1.Length; i++) {
+					if (array1[i] != array2[i])
+						return false;
+				}
+			}
+			return bResult;
+		}
+
+		public bool Equals (byte[] asn1) 
+		{
+			return CompareArray (this.GetBytes (), asn1);
+		}
+
+		public bool CompareValue (byte[] value) 
+		{
+			return CompareArray (m_aValue, value);
+		}
+
+		public ASN1 Add (ASN1 asn1) 
+		{
+			if (asn1 != null) {
+				if (elist == null)
+					elist = new ArrayList ();
+				elist.Add (asn1);
+			}
+			return asn1;
+		}
+
+		public virtual byte[] GetBytes () 
+		{
+			byte[] val = null;
+			
+			if (Count > 0) {
+				int esize = 0;
+				ArrayList al = new ArrayList ();
+				foreach (ASN1 a in elist) {
+					byte[] item = a.GetBytes ();
+					al.Add (item);
+					esize += item.Length;
+				}
+				val = new byte [esize];
+				int pos = 0;
+				for (int i=0; i < elist.Count; i++) {
+					byte[] item = (byte[]) al[i];
+					Buffer.BlockCopy (item, 0, val, pos, item.Length);
+					pos += item.Length;
+				}
+			} else if (m_aValue != null) {
+				val = m_aValue;
+			}
+
+			byte[] der;
+			int nLengthLen = 0;
+
+			if (val != null) {
+				int nLength = val.Length;
+				// special for length > 127
+				if (nLength > 127) {
+					if (nLength <= Byte.MaxValue) {
+						der = new byte [3 + nLength];
+						Buffer.BlockCopy (val, 0, der, 3, nLength);
+						nLengthLen = 0x81;
+						der[2] = (byte)(nLength);
+					}
+					else if (nLength <= UInt16.MaxValue) {
+						der = new byte [4 + nLength];
+						Buffer.BlockCopy (val, 0, der, 4, nLength);
+						nLengthLen = 0x82;
+						der[2] = (byte)(nLength >> 8);
+						der[3] = (byte)(nLength);
+					}
+					else if (nLength <= 0xFFFFFF) {
+						// 24 bits
+						der = new byte [5 + nLength];
+						Buffer.BlockCopy (val, 0, der, 5, nLength);
+						nLengthLen = 0x83;
+						der [2] = (byte)(nLength >> 16);
+						der [3] = (byte)(nLength >> 8);
+						der [4] = (byte)(nLength);
+					}
+					else {
+						// max (Length is an integer) 32 bits
+						der = new byte [6 + nLength];
+						Buffer.BlockCopy (val, 0, der, 6, nLength);
+						nLengthLen = 0x84;
+						der [2] = (byte)(nLength >> 24);
+						der [3] = (byte)(nLength >> 16);
+						der [4] = (byte)(nLength >> 8);
+						der [5] = (byte)(nLength);
+					}
+				}
+				else {
+					// basic case (no encoding)
+					der = new byte [2 + nLength];
+					Buffer.BlockCopy (val, 0, der, 2, nLength);
+					nLengthLen = nLength;
+				}
+				if (m_aValue == null)
+					m_aValue = val;
+			}
+			else
+				der = new byte[2];
+
+			der[0] = m_nTag;
+			der[1] = (byte)nLengthLen;
+
+			return der;
+		}
+
+		// Note: Recursive
+		protected void Decode (byte[] asn1, ref int anPos, int anLength) 
+		{
+			byte nTag;
+			int nLength;
+			byte[] aValue;
+
+			// minimum is 2 bytes (tag + length of 0)
+			while (anPos < anLength - 1) {
+				DecodeTLV (asn1, ref anPos, out nTag, out nLength, out aValue);
+				// sometimes we get trailing 0
+				if (nTag == 0)
+					continue;
+
+				ASN1 elm = Add (new ASN1 (nTag, aValue));
+
+				if ((nTag & 0x20) == 0x20) {
+					int nConstructedPos = anPos;
+					elm.Decode (asn1, ref nConstructedPos, nConstructedPos + nLength);
+				}
+				anPos += nLength; // value length
+			}
+		}
+
+		// TLV : Tag - Length - Value
+		protected void DecodeTLV (byte[] asn1, ref int pos, out byte tag, out int length, out byte[] content) 
+		{
+			tag = asn1 [pos++];
+			length = asn1 [pos++];
+
+			// special case where L contains the Length of the Length + 0x80
+			if ((length & 0x80) == 0x80) {
+				int nLengthLen = length & 0x7F;
+				length = 0;
+				for (int i = 0; i < nLengthLen; i++)
+					length = length * 256 + asn1 [pos++];
+			}
+
+			content = new byte [length];
+			Buffer.BlockCopy (asn1, pos, content, 0, length);
+		}
+
+		public ASN1 this [int index] {
+			get { 		
+				try {
+					if ((elist == null) || (index >= elist.Count))
+						return null;
+					return (ASN1) elist [index];
+				}
+				catch (ArgumentOutOfRangeException) {
+					return null;
+				}
+			}
+		}
+
+		public ASN1 Element (int index, byte anTag) 
+		{
+			try {
+				if ((elist == null) || (index >= elist.Count))
+					return null;
+
+				ASN1 elm = (ASN1) elist [index];
+				if (elm.Tag == anTag)
+					return elm;
+				else
+					return null;
+			}
+			catch (ArgumentOutOfRangeException) {
+				return null;
+			}
+		}
+
+		public override string ToString()
+		{
+			StringBuilder hexLine = new StringBuilder ();
+            
+			// Add tag
+			hexLine.AppendFormat ("Tag: {0} {1}", m_nTag.ToString ("X2"), Environment.NewLine);
+
+			// Add length
+			hexLine.AppendFormat ("Length: {0} {1}", Value.Length, Environment.NewLine);
+
+			// Add value
+			hexLine.Append ("Value: ");
+			hexLine.Append (Environment.NewLine);
+			for (int i = 0; i < Value.Length; i++) {
+				hexLine.AppendFormat ("{0} ", Value [i].ToString ("X2"));
+				if ((i+1) % 16 == 0)
+					hexLine.AppendFormat (Environment.NewLine);
+			}
+			return hexLine.ToString ();
+		}
+
+		public void SaveToFile (string filename)
+		{
+			if (filename == null)
+				throw new ArgumentNullException ("filename");
+
+			using (FileStream fs = File.Create (filename)) {
+				byte[] data = GetBytes ();
+				fs.Write (data, 0, data.Length);
+			}
+		}
+	}
+}