Add initial work on the NetworkPortalBlock

src/main/java/li/cil/oc2/common/Config.java

@@ -45,6 +45,12 @@ public final class Config {
     @Path("admin.virtual_network") public static int ethernetFrameTimeToLive = 12;
     @Path("admin.virtual_network") public static int hubEthernetFramesPerTick = 32;
 
+    @Path("vxlan") public static boolean enable = false;
+    @Path("vxlan") public static String remoteHost = "::1";
+    @Path("vxlan") public static int remotePort = 4789;
+    @Path("vxlan") public static String bindHost = "::1";
+    @Path("vxlan") public static int bindPort = 4789;
+
     public static boolean computersUseEnergy() {
         return computerEnergyPerTick > 0 && computerEnergyStorage > 0;
     }

src/main/java/li/cil/oc2/common/Main.java

@@ -22,7 +22,11 @@ import li.cil.oc2.common.tags.BlockTags;
 import li.cil.oc2.common.tags.ItemTags;
 import li.cil.oc2.common.util.RegistryUtils;
 import li.cil.oc2.common.util.SoundEvents;
+<<<<<<< HEAD
 import li.cil.oc2.common.vm.provider.DeviceTreeProviders;
+=======
+import li.cil.oc2.common.vxlan.TunnelManager;
+>>>>>>> 7a7b14ef (Add initial work on the NetworkPortalBlock)
 import li.cil.sedna.Sedna;
 import net.minecraftforge.api.distmarker.Dist;
 import net.minecraftforge.fml.DistExecutor;
@@ -54,8 +58,10 @@ public final class Main {
 
         ProviderRegistry.initialize();
         DeviceTypes.initialize();
+
         BlockDeviceDataRegistry.initialize();
         FirmwareRegistry.initialize();
+        TunnelManager.initialize();
 
         DistExecutor.unsafeRunWhenOn(Dist.CLIENT, () -> Manuals::initialize);
 

src/main/java/li/cil/oc2/common/block/NetworkPortalBlock.java

@@ -0,0 +1,35 @@
+package li.cil.oc2.common.block;
+
+import li.cil.oc2.common.blockentity.BlockEntities;
+import net.minecraft.core.BlockPos;
+import net.minecraft.core.Direction;
+import net.minecraft.world.item.context.BlockPlaceContext;
+import net.minecraft.world.level.block.EntityBlock;
+import net.minecraft.world.level.block.HorizontalDirectionalBlock;
+import net.minecraft.world.level.block.SoundType;
+import net.minecraft.world.level.block.entity.BlockEntity;
+import net.minecraft.world.level.block.state.BlockState;
+import net.minecraft.world.level.material.Material;
+import org.jetbrains.annotations.Nullable;
+
+public class NetworkPortalBlock extends HorizontalDirectionalBlock implements EntityBlock {
+
+    public NetworkPortalBlock() {
+        super(Properties
+            .of(Material.METAL)
+            .sound(SoundType.METAL)
+            .strength(1.5f, 6.0f));
+        registerDefaultState(getStateDefinition().any().setValue(FACING, Direction.NORTH));
+    }
+
+    @Override
+    public BlockState getStateForPlacement(final BlockPlaceContext context) {
+        return super.defaultBlockState().setValue(FACING, context.getHorizontalDirection().getOpposite());
+    }
+
+    @Nullable
+    @Override
+    public BlockEntity newBlockEntity(final BlockPos pos, final BlockState state) {
+        return BlockEntities.NETWORK_HUB.get().create(pos, state);
+    }
+}

src/main/java/li/cil/oc2/common/vxlan/TunnelManager.java

@@ -0,0 +1,82 @@
+package li.cil.oc2.common.vxlan;
+
+import li.cil.oc2.api.capabilities.NetworkInterface;
+import li.cil.oc2.common.Config;
+
+import java.io.IOException;
+import java.net.*;
+import java.util.HashMap;
+
+public class TunnelManager {
+
+    private final HashMap<Integer, NetworkInterface> tunnels = new HashMap<>();
+    private final DatagramSocket socket;
+    private static TunnelManager INSTANCE;
+
+    public TunnelManager(InetAddress bindHost, short bindPort, InetAddress remoteHost, short remotePort) throws SocketException {
+        socket = new DatagramSocket(bindPort, bindHost);
+        socket.connect(remoteHost, remotePort);
+    }
+
+    public static void initialize() {
+        if (Config.enable) {
+            try {
+                INSTANCE = new TunnelManager(
+                    InetAddress.getByName(Config.bindHost), Config.bindPort,
+                    InetAddress.getByName(Config.remoteHost), Config.remotePort
+                );
+            } catch (SocketException | UnknownHostException e) {
+                e.printStackTrace();
+            }
+
+            new Thread(new Runnable() {
+                @Override
+                public void run() {
+                    INSTANCE.listen();
+                }
+            }).start();
+        }
+    }
+
+    public void listen() {
+        byte[] buffer = new byte[65535];
+        try {
+            while (true) {
+                DatagramPacket packet = new DatagramPacket(buffer, buffer.length);
+                socket.receive(packet);
+
+                if (packet.getData().length < 8) {
+                    continue;
+                }
+
+                byte flags = packet.getData()[0];
+                int vni_1 = packet.getData()[4];
+
+                if ((flags & 0x08) != 0x08) {
+                    continue;
+                }
+
+                NetworkInterface iface = tunnels.get(vni);
+
+                if (iface != null) {
+                    byte[] inner = new byte[packet.getData().length - 8];
+                    copyBytes(packet.getData(), inner, 8, 0, packet.getData().length - 8);
+
+                    iface.writeEthernetFrame(null, inner, 255);
+                }
+            }
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+    }
+
+    public static TunnelManager instance() {
+        return INSTANCE;
+    }
+
+    private void copyBytes(byte[] input, byte[] output, int inputOffset, int outputOffset, int length) {
+        for (int i = 0; i < length; i++) {
+            output[outputOffset + i] = input[inputOffset + i];
+        }
+    }
+}