fix broken UDP plugin interface

compujuckel · Dec 20, 2023 · 45b3433 · 45b3433
1 parent 2b74e96
commit 45b3433
Show file tree

Hide file tree

Showing 4 changed files with 34 additions and 12 deletions.
diff --git a/AssettoServer/Network/Udp/ACUdpServer.cs b/AssettoServer/Network/Udp/ACUdpServer.cs
@@ -54,12 +54,7 @@ protected override async Task ExecuteAsync(CancellationToken stoppingToken)
     {
         Log.Information("Starting UDP server on port {Port}", _port);
 
-        // https://stackoverflow.com/questions/5199026/c-sharp-async-udp-listener-socketexception
-        if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
-        {
-            _socket.IOControl(-1744830452 /* SIO_UDP_CONNRESET */, new byte[] { 0, 0, 0, 0 }, null);
-        }
-
+        _socket.DisableUdpIcmpExceptions();       
         _socket.ReceiveTimeout = 1000;
         _socket.Bind(new IPEndPoint(IPAddress.Any, _port));
         await Task.Factory.StartNew(() => ReceiveLoop(stoppingToken), TaskCreationOptions.LongRunning);

diff --git a/AssettoServer/Network/Udp/UdpPluginServer.cs b/AssettoServer/Network/Udp/UdpPluginServer.cs
@@ -14,6 +14,7 @@
 using AssettoServer.Shared.Network.Packets.Shared;
 using AssettoServer.Shared.Network.Packets.UdpPlugin;
 using AssettoServer.Shared.Services;
+using AssettoServer.Utils;
 using Microsoft.Extensions.Hosting;
 using Serilog;
 using ClientEvent = AssettoServer.Shared.Network.Packets.UdpPlugin.ClientEvent;
@@ -63,23 +64,25 @@ public UdpPluginServer(
         {
             throw new ConfigurationException("UDP_PLUGIN_ADDRESS is invalid, needs to be in format 0.0.0.0:10000");
         }
-        var ip = addressSplit[0];
+        var ip = IPAddress.Parse(addressSplit[0]);
 
         if (_configuration.Server.UdpPluginLocalPort == outPort)
         {
             throw new ConfigurationException("UDP_PLUGIN_ADDRESS port needs to be different from UDP_PLUGIN_LOCAL_PORT");
         }
 
-        _outAddress = new IPEndPoint(IPAddress.Parse(ip), outPort).Serialize();
-        _inAddress = new IPEndPoint(IPAddress.Any, _configuration.Server.UdpPluginLocalPort).Serialize();
+        _outAddress = new IPEndPoint(ip, outPort).Serialize();
+        _inAddress = new IPEndPoint(ip, _configuration.Server.UdpPluginLocalPort).Serialize();
 
         _socket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
     }
 
     protected override async Task ExecuteAsync(CancellationToken cancellationToken)
     {
         Log.Information("Starting UDP plugin server on port {Port}", _configuration.Server.UdpPluginLocalPort);
-
+
+        _socket.DisableUdpIcmpExceptions();
+        _socket.ReceiveTimeout = 1000;
         _socket.Bind(new IPEndPoint(IPAddress.Any, _configuration.Server.UdpPluginLocalPort));
 
         Task realtimeTask = Task.Run(async () =>
@@ -140,7 +143,7 @@ private void ReceiveLoop(CancellationToken stoppingToken)
             try
             {
                 var bytesRead = _socket.ReceiveFrom(buffer, SocketFlags.None, address);
-                if (address.Equals(_inAddress))
+                if (address.IpEquals(_inAddress))
                 {
                     OnReceived(buffer, bytesRead);
                 }
@@ -149,6 +152,7 @@ private void ReceiveLoop(CancellationToken stoppingToken)
                     Log.Information("Ignoring UDP Plugin packet from address {Address}", address);
                 }
             }
+            catch (SocketException ex) when (ex.SocketErrorCode == SocketError.TimedOut) { }
             catch (Exception ex)
             {
                 Log.Error(ex, "Error in UDP plugin receive loop");

diff --git a/AssettoServer/Utils/SocketAddressExtensions.cs b/AssettoServer/Utils/SocketAddressExtensions.cs
@@ -1,4 +1,5 @@
-using System.Net;
+using System;
+using System.Net;
 
 namespace AssettoServer.Utils;
 
@@ -10,4 +11,10 @@ public static SocketAddress Clone(this SocketAddress address)
         address.Buffer.CopyTo(clone.Buffer);
         return clone;
     }
+
+    public static bool IpEquals(this SocketAddress address, SocketAddress other)
+    {
+        // This works for IPv4 only. First two bytes = port, next 4 bytes = address
+        return address.Buffer.Span[2..6].SequenceEqual(other.Buffer.Span[2..6]);
+    }
 }
diff --git a/AssettoServer/Utils/SocketExtensions.cs b/AssettoServer/Utils/SocketExtensions.cs
@@ -0,0 +1,16 @@
+using System.Net.Sockets;
+using System.Runtime.InteropServices;
+
+namespace AssettoServer.Utils;
+
+public static class SocketExtensions
+{
+    public static void DisableUdpIcmpExceptions(this Socket socket)
+    {
+        // https://stackoverflow.com/questions/5199026/c-sharp-async-udp-listener-socketexception
+        if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
+        {
+            socket.IOControl(-1744830452 /* SIO_UDP_CONNRESET */, new byte[] { 0, 0, 0, 0 }, null);
+        }
+    }
+}