Implement convenience class for Ssl heavy lifting

SslHelper does the actual Ssl thing-a-magix involved
in updating the Tcp stream. Eventually, it will provide
at least one more delegate to allow us to change the default
behaviour of the Certificate validation routine

Author: essiene

src/client/api/SslHelper.cs

@@ -0,0 +1,89 @@
+// This source code is dual-licensed under the Apache License, version
+// 2.0, and the Mozilla Public License, version 1.1.
+//
+// The APL v2.0:
+//
+//---------------------------------------------------------------------------
+//   Copyright (C) 2007-2009 LShift Ltd., Cohesive Financial
+//   Technologies LLC., and Rabbit Technologies Ltd.
+//
+//   Licensed under the Apache License, Version 2.0 (the "License");
+//   you may not use this file except in compliance with the License.
+//   You may obtain a copy of the License at
+//
+//       http://www.apache.org/licenses/LICENSE-2.0
+//
+//   Unless required by applicable law or agreed to in writing, software
+//   distributed under the License is distributed on an "AS IS" BASIS,
+//   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+//   See the License for the specific language governing permissions and
+//   limitations under the License.
+//---------------------------------------------------------------------------
+//
+// The MPL v1.1:
+//
+//---------------------------------------------------------------------------
+//   The contents of this file are subject to the Mozilla Public License
+//   Version 1.1 (the "License"); you may not use this file except in
+//   compliance with the License. You may obtain a copy of the License at
+//   http://www.rabbitmq.com/mpl.html
+//
+//   Software distributed under the License is distributed on an "AS IS"
+//   basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the
+//   License for the specific language governing rights and limitations
+//   under the License.
+//
+//   The Original Code is The RabbitMQ .NET Client.
+//
+//   The Initial Developers of the Original Code are LShift Ltd,
+//   Cohesive Financial Technologies LLC, and Rabbit Technologies Ltd.
+//
+//   Portions created before 22-Nov-2008 00:00:00 GMT by LShift Ltd,
+//   Cohesive Financial Technologies LLC, or Rabbit Technologies Ltd
+//   are Copyright (C) 2007-2008 LShift Ltd, Cohesive Financial
+//   Technologies LLC, and Rabbit Technologies Ltd.
+//
+//   Portions created by LShift Ltd are Copyright (C) 2007-2009 LShift
+//   Ltd. Portions created by Cohesive Financial Technologies LLC are
+//   Copyright (C) 2007-2009 Cohesive Financial Technologies
+//   LLC. Portions created by Rabbit Technologies Ltd are Copyright
+//   (C) 2007-2009 Rabbit Technologies Ltd.
+//
+//   All Rights Reserved.
+//
+//   Contributor(s): ______________________________________.
+//
+//---------------------------------------------------------------------------
+using System;
+using System.Collections;
+using System.IO;
+using System.Net.Security;
+using System.Security.Authentication;
+using System.Security.Cryptography.X509Certificates;
+using RabbitMQ.Client.Impl;
+
+namespace RabbitMQ.Client
+{
+
+    ///<summary>Represents an SslHelper which does the actual heavy lifting
+    ///to set up an SSL connection, using the config options in an SslOption
+    ///to make things cleaner</summary>
+    public class SslHelper
+    {
+
+        ///<summary>Upgrade a Tcp stream to an Ssl stream using the SSL options
+        ///provided</summary>
+        public static Stream TcpUpgrade(Stream tcpStream, SslOption sslOption)
+        {
+            SslStream sslStream = new SslStream(tcpStream, false);
+            
+            sslStream.AuthenticateAsClient(sslOption.ServerName,
+                        sslOption.CertCollection,
+                        sslOption.SslVersion,
+                        false);
+
+            return sslStream;
+        }
+
+    }
+}