Udp support

neo/Network/P2P/Capabilities/NodeCapability.cs

@@ -39,6 +39,7 @@ public static NodeCapability DeserializeFrom(BinaryReader reader)
             switch (type)
             {
                 case NodeCapabilityType.TcpServer:
+                case NodeCapabilityType.UdpServer:
                 case NodeCapabilityType.WsServer:
                     capability = new ServerCapability(type);
                     break;

neo/Network/P2P/Capabilities/NodeCapabilityType.cs

@@ -5,6 +5,7 @@ public enum NodeCapabilityType : byte
         //Servers
         TcpServer = 0x01,
         WsServer = 0x02,
+        UdpServer = 0x03,
 
         //Others
         FullNode = 0x10

neo/Network/P2P/Capabilities/ServerCapability.cs

@@ -18,7 +18,7 @@ public class ServerCapability : NodeCapability
         /// <param name="port">Port</param>
         public ServerCapability(NodeCapabilityType type, ushort port = 0) : base(type)
         {
-            if (type != NodeCapabilityType.TcpServer && type != NodeCapabilityType.WsServer)
+            if (type != NodeCapabilityType.TcpServer && type != NodeCapabilityType.UdpServer && type != NodeCapabilityType.WsServer)
             {
                 throw new ArgumentException(nameof(type));
             }

neo/Network/P2P/ChannelsConfig.cs

@@ -14,6 +14,11 @@ public class ChannelsConfig
         /// </summary>
         public IPEndPoint WebSocket { get; set; }
 
+        /// <summary>
+        /// Udp configuration
+        /// </summary>
+        public IPEndPoint Udp { get; set; }
+
         /// <summary>
         /// Minimum desired connections
         /// </summary>

neo/Network/P2P/LocalNode.cs

@@ -1,4 +1,5 @@
 using Akka.Actor;
+using Akka.IO;
 using Neo.IO;
 using Neo.Ledger;
 using Neo.Network.P2P.Payloads;
@@ -23,6 +24,7 @@ internal class SendDirectly { public IInventory Inventory; }
 
         private static readonly object lockObj = new object();
         private readonly NeoSystem system;
+        private readonly IActorRef protocol;
         internal readonly ConcurrentDictionary<IActorRef, RemoteNode> RemoteNodes = new ConcurrentDictionary<IActorRef, RemoteNode>();
 
         public int ConnectedCount => RemoteNodes.Count;
@@ -53,7 +55,9 @@ public LocalNode(NeoSystem system)
             {
                 if (singleton != null)
                     throw new InvalidOperationException();
+
                 this.system = system;
+                protocol = Context.ActorOf(ProtocolHandler.Props(system));
                 singleton = this;
             }
         }
@@ -75,7 +79,7 @@ private static IPEndPoint GetIPEndpointFromHostPort(string hostNameOrAddress, in
             IPHostEntry entry;
             try
             {
-                entry = Dns.GetHostEntry(hostNameOrAddress);
+                entry = System.Net.Dns.GetHostEntry(hostNameOrAddress);
             }
             catch (SocketException)
             {
@@ -139,6 +143,12 @@ protected override void OnReceive(object message)
             base.OnReceive(message);
             switch (message)
             {
+                case Udp.Received udp:
+                    {
+                        if (Message.TryDeserialize(udp.Data, out var msg) != udp.Data.Count) return;
+                        protocol.Tell(new UdpRequest((IPEndPoint)udp.Sender, msg));
+                        break;
+                    }
                 case Message msg:
                     BroadcastMessage(msg);
                     break;
@@ -156,6 +166,19 @@ protected override void OnReceive(object message)
             }
         }
 
+        public NetworkAddressWithTime[] GetPeers()
+        {
+            Random rand = new Random();
+
+            return RemoteNodes.Values
+                .Where(p => p.ListenerTcpPort > 0)
+                .GroupBy(p => p.Remote.Address, (k, g) => g.First())
+                .OrderBy(p => rand.Next())
+                .Take(AddrPayload.MaxCountToSend)
+                .Select(p => NetworkAddressWithTime.Create(p.Listener.Address, p.Version.Timestamp, p.Version.Capabilities))
+                .ToArray();
+        }
+
         private void OnRelay(IInventory inventory)
         {
             if (inventory is Transaction transaction)

neo/Network/P2P/Peer.cs

@@ -28,7 +28,10 @@ private class WsConnected { public WebSocket Socket; public IPEndPoint Remote; p
         public const int DefaultMaxConnections = DefaultMinDesiredConnections * 4;
 
         private static readonly IActorRef tcp_manager = Context.System.Tcp();
+        private static readonly IActorRef udp_manager = Context.System.Udp();
+
         private IActorRef tcp_listener;
+        private IActorRef udp_listener;
         private IWebHost ws_host;
         private ICancelable timer;
         protected ActorSelection Connections => Context.ActorSelection("connection_*");
@@ -41,6 +44,7 @@ private class WsConnected { public WebSocket Socket; public IPEndPoint Remote; p
         protected HashSet<IPAddress> TrustedIpAddresses { get; } = new HashSet<IPAddress>();
 
         public int ListenerTcpPort { get; private set; }
+        public int ListenerUdpPort { get; private set; }
         public int ListenerWsPort { get; private set; }
         public int MaxConnectionsPerAddress { get; private set; } = 3;
         public int MinDesiredConnections { get; private set; } = DefaultMinDesiredConnections;
@@ -123,6 +127,12 @@ protected override void OnReceive(object message)
                 case Tcp.Bound _:
                     tcp_listener = Sender;
                     break;
+                case Udp.Bound _:
+                    udp_listener = Sender;
+                    break;
+                case UdpResponse udp:
+                    udp_listener.Tell(Udp.Send.Create(udp.Data, udp.Sender));
+                    break;
                 case Tcp.CommandFailed commandFailed:
                     OnTcpCommandFailed(commandFailed.Cmd);
                     break;
@@ -136,13 +146,14 @@ private void OnStart(ChannelsConfig config)
         {
             ListenerTcpPort = config.Tcp?.Port ?? 0;
             ListenerWsPort = config.WebSocket?.Port ?? 0;
+            ListenerUdpPort = config.Udp?.Port ?? 0;
 
             MinDesiredConnections = config.MinDesiredConnections;
             MaxConnections = config.MaxConnections;
             MaxConnectionsPerAddress = config.MaxConnectionsPerAddress;
 
             timer = Context.System.Scheduler.ScheduleTellRepeatedlyCancelable(0, 5000, Context.Self, new Timer(), ActorRefs.NoSender);
-            if ((ListenerTcpPort > 0 || ListenerWsPort > 0)
+            if ((ListenerTcpPort > 0 || ListenerWsPort > 0 || ListenerUdpPort > 0)
                 && localAddresses.All(p => !p.IsIPv4MappedToIPv6 || IsIntranetAddress(p))
                 && UPnP.Discover())
             {
@@ -151,6 +162,7 @@ private void OnStart(ChannelsConfig config)
                     localAddresses.Add(UPnP.GetExternalIP());
 
                     if (ListenerTcpPort > 0) UPnP.ForwardPort(ListenerTcpPort, ProtocolType.Tcp, "NEO Tcp");
+                    if (ListenerUdpPort > 0) UPnP.ForwardPort(ListenerUdpPort, ProtocolType.Udp, "NEO Udp");
                     if (ListenerWsPort > 0) UPnP.ForwardPort(ListenerWsPort, ProtocolType.Tcp, "NEO WebSocket");
                 }
                 catch { }
@@ -172,6 +184,10 @@ private void OnStart(ChannelsConfig config)
                 ws_host = new WebHostBuilder().UseKestrel().UseUrls($"http://{host}:{ListenerWsPort}").Configure(app => app.UseWebSockets().Run(ProcessWebSocketAsync)).Build();
                 ws_host.Start();
             }
+            if (ListenerUdpPort > 0)
+            {
+                udp_manager.Tell(new Udp.Bind(Self, config.Udp));
+            }
         }
 
         private void OnTcpConnected(IPEndPoint remote, IPEndPoint local)
@@ -253,6 +269,7 @@ protected override void PostStop()
             timer.CancelIfNotNull();
             ws_host?.Dispose();
             tcp_listener?.Tell(Tcp.Unbind.Instance);
+            udp_listener?.Tell(Udp.Unbind.Instance);
             base.PostStop();
         }