jellyfin/Mono.Nat/NatUtility.cs

//
// Authors:
//   Ben Motmans <ben.motmans@gmail.com>
//   Nicholas Terry <nick.i.terry@gmail.com>
//
// Copyright (C) 2007 Ben Motmans
// Copyright (C) 2014 Nicholas Terry
//
// 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.Net;
using System.Net.Sockets;
using System.Threading;
using System.Linq;
using System.Collections.Generic;
using System.IO;
using System.Net.NetworkInformation;
using MediaBrowser.Controller.Dlna;
using MediaBrowser.Model.Logging;
using Mono.Nat.Pmp.Mappers;
using Mono.Nat.Upnp.Mappers;

namespace Mono.Nat
{
	public static class NatUtility
	{
        private static ManualResetEvent searching;
		public static event EventHandler<DeviceEventArgs> DeviceFound;
		public static event EventHandler<DeviceEventArgs> DeviceLost;
        
        public static event EventHandler<UnhandledExceptionEventArgs> UnhandledException;

		private static List<ISearcher> controllers;
		private static bool verbose;

        public static List<NatProtocol> EnabledProtocols { get; set; }

	    public static ILogger Logger { get; set; }

	    public static bool Verbose
		{
			get { return verbose; }
			set { verbose = value; }
		}
		
        static NatUtility()
        {
            EnabledProtocols = new List<NatProtocol>
            {
                NatProtocol.Upnp,
                NatProtocol.Pmp
            };

            searching = new ManualResetEvent(false);

            controllers = new List<ISearcher>();
            controllers.Add(UpnpSearcher.Instance);
            controllers.Add(PmpSearcher.Instance);

            controllers.ForEach(searcher =>
                {
                    searcher.DeviceFound += (sender, args) =>
                    {
                        if (DeviceFound != null)
                            DeviceFound(sender, args);
                    };
                    searcher.DeviceLost += (sender, args) =>
                    {
                        if (DeviceLost != null)
                            DeviceLost(sender, args);
                    };
                });
            Thread t = new Thread(SearchAndListen);
            t.IsBackground = true;
            t.Start();
        }

		internal static void Log(string format, params object[] args)
		{
			var logger = Logger;
		    if (logger != null)
		        logger.Debug(format, args);
		}

        private static void SearchAndListen()
        {
            while (true)
            {
                searching.WaitOne();

                try
                {
                    var enabledProtocols = EnabledProtocols.ToList();

                    if (enabledProtocols.Contains(UpnpSearcher.Instance.Protocol))
                    {
                        Receive(UpnpSearcher.Instance, UpnpSearcher.sockets);
                    }
                    if (enabledProtocols.Contains(PmpSearcher.Instance.Protocol))
                    {
                        Receive(PmpSearcher.Instance, PmpSearcher.sockets);
                    }

                    foreach (ISearcher s in controllers)
                        if (s.NextSearch < DateTime.Now && enabledProtocols.Contains(s.Protocol))
                        {
                            Log("Searching for: {0}", s.GetType().Name);
							s.Search();
                        }
                }
                catch (Exception e)
                {
                    if (UnhandledException != null)
                        UnhandledException(typeof(NatUtility), new UnhandledExceptionEventArgs(e, false));
                }
				Thread.Sleep(10);
            }
		}

		static void Receive (ISearcher searcher, List<UdpClient> clients)
		{
			IPEndPoint received = new IPEndPoint(IPAddress.Parse("192.168.0.1"), 5351);
			foreach (UdpClient client in clients)
			{
				if (client.Available > 0)
				{
				    IPAddress localAddress = ((IPEndPoint)client.Client.LocalEndPoint).Address;
					byte[] data = client.Receive(ref received);
					searcher.Handle(localAddress, data, received);
				}
            }
        }

        static void Receive(IMapper mapper, List<UdpClient> clients)
        {
            IPEndPoint received = new IPEndPoint(IPAddress.Parse("192.168.0.1"), 5351);
            foreach (UdpClient client in clients)
            {
                if (client.Available > 0)
                {
                    IPAddress localAddress = ((IPEndPoint)client.Client.LocalEndPoint).Address;
                    byte[] data = client.Receive(ref received);
                    mapper.Handle(localAddress, data);
                }
            }
        }
		
		public static void StartDiscovery ()
		{
            searching.Set();
		}

		public static void StopDiscovery ()
		{
            searching.Reset();
		}

        //This is for when you know the Gateway IP and want to skip the costly search...
        public static void DirectMap(IPAddress gatewayAddress, MapperType type)
        {
            IMapper mapper;
            switch (type)
            {
                case MapperType.Pmp:
                    mapper = new PmpMapper();
                    break;
                case MapperType.Upnp:
                    mapper = new UpnpMapper();
                    mapper.DeviceFound += (sender, args) =>
                    {
                        if (DeviceFound != null)
                            DeviceFound(sender, args);
                    };
                    mapper.Map(gatewayAddress);                    
                    break;
                default:
                    throw new InvalidOperationException("Unsuported type given");

            }
            searching.Reset();
            
        }

        //So then why is it here? -Nick
		[Obsolete ("This method serves no purpose and shouldn't be used")]
		public static IPAddress[] GetLocalAddresses (bool includeIPv6)
		{
			List<IPAddress> addresses = new List<IPAddress> ();

			IPHostEntry hostInfo = Dns.GetHostEntry (Dns.GetHostName ());
			foreach (IPAddress address in hostInfo.AddressList) {
				if (address.AddressFamily == AddressFamily.InterNetwork ||
					(includeIPv6 && address.AddressFamily == AddressFamily.InterNetworkV6)) {
					addresses.Add (address);
				}
			}
			
			return addresses.ToArray ();
		}
		
		//checks if an IP address is a private address space as defined by RFC 1918
		public static bool IsPrivateAddressSpace (IPAddress address)
		{
			byte[] ba = address.GetAddressBytes ();

			switch ((int)ba[0]) {
			case 10:
				return true; //10.x.x.x
			case 172:
				return ((int)ba[1] & 16) != 0; //172.16-31.x.x
			case 192:
				return (int)ba[1] == 168; //192.168.x.x
			default:
				return false;
			}
		}

	    public static void Handle(IPAddress localAddress, byte[] response, IPEndPoint endpoint, NatProtocol protocol)
	    {
	        switch (protocol)
	        {
                case NatProtocol.Upnp:
	                UpnpSearcher.Instance.Handle(localAddress, response, endpoint);
	                break;
                case NatProtocol.Pmp:
	                PmpSearcher.Instance.Handle(localAddress, response, endpoint);
	                break;
	            default:
	                throw new ArgumentException("Unexpected protocol: " + protocol);
	        }
        }

        public static void Handle(IPAddress localAddress, UpnpDeviceInfo deviceInfo, IPEndPoint endpoint, NatProtocol protocol)
        {
            switch (protocol)
            {
                case NatProtocol.Upnp:
                    UpnpSearcher.Instance.Handle(localAddress, deviceInfo, endpoint);
                    break;
                default:
                    throw new ArgumentException("Unexpected protocol: " + protocol);
            }
        }
    }
}