EndPointManager.cs

//
// System.Net.EndPointManager
//
// Author:
//	Gonzalo Paniagua Javier (gonzalo@ximian.com)
//
// Copyright (c) 2005 Novell, Inc. (http://www.novell.com)
// Copyright (c) 2018 Nivloc Enterprises Ltd

//
// 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.
//

#if SECURITY_DEP

using System;

#if SSHARP
using System.Linq;
using Crestron.SimplSharp;
#else
#endif

using System.Collections;
using System.Collections.Generic;

#if SSHARP
namespace SSMono.Net
#else
namespace System.Net
#endif
	{
	internal sealed class EndPointManager
		{
		// Dictionary<IPAddress, Dictionary<int, EndPointListener>>
		private static Hashtable ip_to_endpoints = new Hashtable ();

		private EndPointManager ()
			{
			}

		public static void AddListener (HttpListener listener)
			{
			ArrayList added = new ArrayList ();
			try
				{
				lock (ip_to_endpoints)
					{
					foreach (string prefix in listener.Prefixes)
						{
						AddPrefixInternal (prefix, listener);
						added.Add (prefix);
						}
					}
				}
			catch
				{
				foreach (string prefix in added)
					RemovePrefix (prefix, listener);
				throw;
				}
			}

		public static void AddPrefix (string prefix, HttpListener listener)
			{
			lock (ip_to_endpoints)
				{
				AddPrefixInternal (prefix, listener);
				}
			}

		private static void AddPrefixInternal (string p, HttpListener listener)
			{
			ListenerPrefix lp = new ListenerPrefix (p);
			if (lp.Path.IndexOf ('%') != -1)
				throw new HttpListenerException (400, "Invalid path.");

			if (lp.Path.IndexOf ("//", StringComparison.Ordinal) != -1) // TODO: Code?
				throw new HttpListenerException (400, "Invalid path.");

			// listens on all the interfaces if host name cannot be parsed by IPAddress.
			EndPointListener epl = GetEPListener (lp.Host, lp.Port, listener, lp.Secure);
			epl.AddPrefix (lp, listener);
			}

		private static EndPointListener GetEPListener (string host, int port, HttpListener listener, bool secure)
			{
			IPAddress addr;
			if (host == "*")
				addr = IPAddress.Any;
#if SSHARP
			else if (IPAddressTryParser.IPAddressTryParse (host, out addr) == false)
#else
			else if (IPAddress.TryParse (host, out addr) == false)
#endif
				{
				try
					{
#if SSHARP
					IPAddress[] addrs = DnsEx.GetHostAddresses (host);
					if (addrs.Length != 0)
						addr = addrs[0];
#else
					IPHostEntry iphost = Dns.GetHostByName (host);
					if (iphost != null)
						addr = iphost.AddressList[0];
#endif
					else
						addr = IPAddress.Any;
					}
				catch
					{
					addr = IPAddress.Any;
					}
				}
			Hashtable p = null; // Dictionary<int, EndPointListener>
			if (ip_to_endpoints.ContainsKey (addr))
				p = (Hashtable)ip_to_endpoints[addr];
			else
				{
				p = new Hashtable ();
				ip_to_endpoints[addr] = p;
				}

			EndPointListener epl = null;
			if (p.ContainsKey (port))
				epl = (EndPointListener)p[port];
			else
				{
				epl = new EndPointListener (addr, port, secure);
				p[port] = epl;
				}

			return epl;
			}

		public static void RemoveEndPoint (EndPointListener epl, IPEndPoint ep)
			{
			lock (ip_to_endpoints)
				{
				// Dictionary<int, EndPointListener> p
				Hashtable p = null;
				p = (Hashtable)ip_to_endpoints[ep.Address];
				p.Remove (ep.Port);
				if (p.Count == 0)
					ip_to_endpoints.Remove (ep.Address);
				epl.Close ();
				}
			}

		public static void RemoveListener (HttpListener listener)
			{
			lock (ip_to_endpoints)
				{
				foreach (string prefix in listener.Prefixes)
					RemovePrefixInternal (prefix, listener);
				}
			}

		public static void RemovePrefix (string prefix, HttpListener listener)
			{
			lock (ip_to_endpoints)
				{
				RemovePrefixInternal (prefix, listener);
				}
			}

		private static void RemovePrefixInternal (string prefix, HttpListener listener)
			{
			ListenerPrefix lp = new ListenerPrefix (prefix);
			if (lp.Path.IndexOf ('%') != -1)
				return;

			if (lp.Path.IndexOf ("//", StringComparison.Ordinal) != -1)
				return;

			EndPointListener epl = GetEPListener (lp.Host, lp.Port, listener, lp.Secure);
			epl.RemovePrefix (lp, listener);
			}
		}
	}

#endif