merge common implementations and server implementations

Emby.Server.Implementations/IO/SharpCifs/Util/Sharpen/MessageDigest.cs

@@ -0,0 +1,118 @@
+using System;
+using System.IO;
+using System.Reflection;
+using System.Security.Cryptography;
+
+namespace SharpCifs.Util.Sharpen
+{
+    public abstract class MessageDigest
+	{
+	    public void Digest (byte[] buffer, int o, int len)
+		{
+			byte[] d = Digest ();
+			d.CopyTo (buffer, o);
+		}
+
+		public byte[] Digest (byte[] buffer)
+		{
+			Update (buffer);
+			return Digest ();
+		}
+
+		public abstract byte[] Digest ();
+		public abstract int GetDigestLength ();
+		public static MessageDigest GetInstance (string algorithm)
+		{
+			switch (algorithm.ToLower ()) {
+			case "sha-1":
+                //System.Security.CryptographySHA1Managed not found
+                //return new MessageDigest<SHA1Managed> ();
+                return new MessageDigest<System.Security.Cryptography.SHA1>();
+            case "md5":
+                return new MessageDigest<Md5Managed> ();
+            }
+			throw new NotSupportedException (string.Format ("The requested algorithm \"{0}\" is not supported.", algorithm));
+		}
+
+		public abstract void Reset ();
+		public abstract void Update (byte[] b);
+		public abstract void Update (byte b);
+		public abstract void Update (byte[] b, int offset, int len);
+	}
+
+
+	public class MessageDigest<TAlgorithm> : MessageDigest where TAlgorithm : HashAlgorithm //, new() //use static `Create` method
+	{
+		private TAlgorithm _hash;
+        //private CryptoStream _stream; //don't work .NET Core
+        private MemoryStream _stream;
+
+
+        public MessageDigest ()
+		{
+			Init ();
+		}
+
+		public override byte[] Digest ()
+		{
+            //CryptoStream -> MemoryStream, needless method
+            //_stream.FlushFinalBlock ();
+
+            //HashAlgorithm.`Hash` property deleted
+            //byte[] hash = _hash.Hash;
+            byte[] hash = _hash.ComputeHash(_stream.ToArray());
+
+            Reset ();
+			return hash;
+		}
+
+		public void Dispose ()
+		{
+			if (_stream != null) {
+				_stream.Dispose ();
+			}
+			_stream = null;
+        }
+
+        public override int GetDigestLength ()
+		{
+			return (_hash.HashSize / 8);
+		}
+
+		private void Init ()
+		{
+            //use static `Create` method
+            //_hash = Activator.CreateInstance<TAlgorithm> ();
+            var createMethod = typeof(TAlgorithm).GetRuntimeMethod("Create", new Type[0]);
+            _hash = (TAlgorithm)createMethod.Invoke(null, new object[] {});
+
+            //HashAlgorithm cannot cast `ICryptoTransform` on .NET Core, gave up using CryptoStream. 
+            //_stream = new CryptoStream(Stream.Null, _hash, CryptoStreamMode.Write);
+            //_stream = new CryptoStream(_tmpStream, (ICryptoTransform)_hash, CryptoStreamMode.Write);
+            _stream = new MemoryStream();
+        }
+
+        public override void Reset ()
+		{
+			Dispose ();
+			Init ();
+		}
+
+		public override void Update (byte[] input)
+		{
+			_stream.Write (input, 0, input.Length);
+		}
+
+		public override void Update (byte input)
+		{
+			_stream.WriteByte (input);
+		}
+
+		public override void Update (byte[] input, int index, int count)
+		{
+			if (count < 0)
+				Console.WriteLine ("Argh!");
+			_stream.Write (input, index, count);
+		}
+	}
+}