add the ability to control udp port from config

common/src/main/java/dev/ryanhcode/sable/SableConfig.java

@@ -17,6 +17,8 @@ public final class SableConfig {
     public static final ModConfigSpec.IntValue SUB_LEVEL_PUNCH_COOLDOWN_TICKS;
     public static final ModConfigSpec.BooleanValue DISABLE_UDP_PIPELINE;
     public static final ModConfigSpec.BooleanValue ATTEMPT_UDP_NETWORKING;
+    public static final ModConfigSpec.IntValue UDP_LISTEN_PORT;
+
 
     static {
         final ModConfigSpec.Builder builder = new ModConfigSpec.Builder();
@@ -56,6 +58,9 @@ public final class SableConfig {
         ATTEMPT_UDP_NETWORKING = builder
                 .comment("If Sable should attempt to authenticate with clients and send them sub-level data over UDP")
                 .define("attempt_udp_networking", true);
+        UDP_LISTEN_PORT = builder
+                .comment("The port Sable will use when sending data over UDP (-1 = The Minecraft Server Instance Port)")
+                .defineInRange("udp_listen_port", -1, -1, 65535);
 
         SPEC = builder.build();
     }

common/src/main/java/dev/ryanhcode/sable/mixin/udp/ConnectionMixin.java

@@ -5,6 +5,7 @@
 import dev.ryanhcode.sable.SableClient;
 import dev.ryanhcode.sable.mixinterface.udp.ConnectionExtension;
 import dev.ryanhcode.sable.network.udp.SableUDPPacket;
+import dev.ryanhcode.sable.network.udp.SableUDPServer;
 import dev.ryanhcode.sable.network.udp.handler.SableUDPChannelHandlerClient;
 import io.netty.bootstrap.Bootstrap;
 import io.netty.channel.*;
@@ -83,7 +84,7 @@ protected void initChannel(final Channel channel) {
                     }
                 })
                 .channel(channelClass)
-                .connect(inetSocketAddress.getAddress(), inetSocketAddress.getPort());
+                .connect(inetSocketAddress.getAddress(), SableUDPServer.getUDPPort(inetSocketAddress.getPort()));
 
         channelFuture.syncUninterruptibly();
     }

common/src/main/java/dev/ryanhcode/sable/mixin/udp/ServerConnectionListenerMixin.java

@@ -9,6 +9,7 @@
 import io.netty.bootstrap.Bootstrap;
 import io.netty.channel.*;
 import io.netty.channel.epoll.Epoll;
+import io.netty.channel.epoll.EpollChannelOption;
 import io.netty.channel.epoll.EpollDatagramChannel;
 import io.netty.channel.local.LocalAddress;
 import io.netty.channel.local.LocalServerChannel;
@@ -75,7 +76,7 @@ protected void initChannel(final Channel channel) {
                         }
                     })
                     .group(eventLoopGroup)
-                    .localAddress(inetAddress, port)
+                    .localAddress(inetAddress, SableUDPServer.getUDPPort(port))
                     .bind()
                     .syncUninterruptibly());
         }

common/src/main/java/dev/ryanhcode/sable/network/packets/tcp/ClientboundSableUDPActivationPacket.java

@@ -5,6 +5,7 @@
 import dev.ryanhcode.sable.network.packets.udp.SableUDPAuthenticationPacket;
 import dev.ryanhcode.sable.network.tcp.SableTCPPacket;
 import dev.ryanhcode.sable.network.udp.AddressedSableUDPPacket;
+import dev.ryanhcode.sable.network.udp.SableUDPServer;
 import foundry.veil.api.network.handler.PacketContext;
 import io.netty.channel.Channel;
 import io.netty.channel.ChannelFuture;
@@ -44,7 +45,10 @@ public void handle(final PacketContext context) {
         final Channel channel = connectionExtension.sable$getUDPChannel();
 
         final InetSocketAddress baseAddress = ((InetSocketAddress) connection.getRemoteAddress());
-        final InetSocketAddress remoteAddress = new InetSocketAddress(baseAddress.getAddress(), baseAddress.getPort());
+        final InetSocketAddress remoteAddress = new InetSocketAddress(
+                baseAddress.getAddress(),
+                SableUDPServer.getUDPPort(baseAddress.getPort())
+        );
 
         Sable.LOGGER.info("Received authentication request, sending response over UDP to {}", remoteAddress);
 

common/src/main/java/dev/ryanhcode/sable/network/packets/udp/SableUDPClientboundKeepAlivePacket.java

@@ -4,6 +4,7 @@
 import dev.ryanhcode.sable.network.udp.AddressedSableUDPPacket;
 import dev.ryanhcode.sable.network.udp.SableUDPPacket;
 import dev.ryanhcode.sable.network.udp.SableUDPPacketType;
+import dev.ryanhcode.sable.network.udp.SableUDPServer;
 import io.netty.channel.Channel;
 import io.netty.channel.ChannelFuture;
 import io.netty.channel.ChannelFutureListener;
@@ -30,7 +31,9 @@ public void handleClient(final Level level) {
         final Channel channel = connectionExtension.sable$getUDPChannel();
 
         final InetSocketAddress baseAddress = ((InetSocketAddress) connection.getRemoteAddress());
-        final InetSocketAddress remoteAddress = new InetSocketAddress(baseAddress.getAddress(), baseAddress.getPort());
+        final InetSocketAddress remoteAddress = new InetSocketAddress(
+                baseAddress.getAddress(),
+                SableUDPServer.getUDPPort(baseAddress.getPort()));
 
         channel.eventLoop().execute(() -> {
             final SableUDPServerboundAlivePacket packet = new SableUDPServerboundAlivePacket();

common/src/main/java/dev/ryanhcode/sable/network/udp/SableUDPServer.java

@@ -17,6 +17,7 @@
 import net.minecraft.network.protocol.common.ClientboundCustomPayloadPacket;
 import net.minecraft.server.MinecraftServer;
 import net.minecraft.server.level.ServerPlayer;
+import net.neoforged.neoforge.common.ModConfigSpec;
 import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.Nullable;
 
@@ -52,6 +53,20 @@ public static SableUDPServer getServer(final MinecraftServer server) {
         return (((ServerConnectionListenerExtension) server.getConnection())).sable$getServer();
     }
 
+    /**
+     * Returns the port that will be used by the UDP server
+     *
+     * @param _default the socket that will be used in the case where the port in config is set to -1
+     * @return the port that will be used by the UDP server
+     */
+    public static Integer getUDPPort(final int _default) {
+        final int fromConfig = SableConfig.UDP_LISTEN_PORT.getAsInt();
+
+        if(fromConfig == -1) return _default;
+
+        return fromConfig;
+    }
+
     /*@Override
     public void flushUDP() {
         if (this.udpChannel.eventLoop().inEventLoop())