change to packet events

bungeeguard-spigot/pom.xml

@@ -38,9 +38,9 @@
             <scope>provided</scope>
         </dependency>
         <dependency>
-            <groupId>com.comphenix.protocol</groupId>
-            <artifactId>ProtocolLib</artifactId>
-            <version>5.0.0-SNAPSHOT</version>
+            <groupId>com.github.retrooper</groupId>
+            <artifactId>packetevents-spigot</artifactId>
+            <version>2.7.0</version>
             <scope>provided</scope>
         </dependency>
         <dependency>

bungeeguard-spigot/src/main/java/me/lucko/bungeeguard/spigot/BungeeGuardBackendPlugin.java

@@ -25,10 +25,11 @@
 
 package me.lucko.bungeeguard.spigot;
 
+import com.github.retrooper.packetevents.PacketEvents;
 import me.lucko.bungeeguard.backend.BungeeGuardBackend;
 import me.lucko.bungeeguard.backend.TokenStore;
+import me.lucko.bungeeguard.spigot.listener.PacketEventsHandshakeListener;
 import me.lucko.bungeeguard.spigot.listener.PaperHandshakeListener;
-import me.lucko.bungeeguard.spigot.listener.ProtocolHandshakeListener;
 
 import org.bukkit.ChatColor;
 import org.bukkit.command.Command;
@@ -46,10 +47,19 @@
  */
 public class BungeeGuardBackendPlugin extends JavaPlugin implements BungeeGuardBackend {
 
+    private static BungeeGuardBackendPlugin instance;
+
     private TokenStore tokenStore;
 
+    @Override
+    public void onLoad() {
+        PacketEvents.getAPI().load();
+    }
+
     @Override
     public void onEnable() {
+        instance = this;
+
         saveDefaultConfig();
         this.tokenStore = new TokenStore(this);
         this.tokenStore.load();
@@ -71,11 +81,13 @@ public void onEnable() {
             PaperHandshakeListener listener = new PaperHandshakeListener(this, this.tokenStore);
             getServer().getPluginManager().registerEvents(listener, this);
 
-        } else if (hasProtocolLib()) {
-            getLogger().info("Using ProtocolLib to listen for connections.");
+        } else if (hasPacketEvents()) {
+            getLogger().info("Using PacketEvents to listen for connections.");
+
+            PacketEvents.getAPI().init();
 
-            ProtocolHandshakeListener listener = new ProtocolHandshakeListener(this, this.tokenStore);
-            listener.registerAdapter(this);
+            PacketEventsHandshakeListener listener = new PacketEventsHandshakeListener(this, this.tokenStore);
+            listener.registerListener();
 
         } else {
             getLogger().severe("------------------------------------------------------------");
@@ -92,6 +104,10 @@ public void onEnable() {
         }
     }
 
+    public static BungeeGuardBackendPlugin getInstance() {
+        return instance;
+    }
+
     @Override
     public boolean onCommand(CommandSender sender, Command command, String label, String[] args) {
         if (!(sender instanceof ConsoleCommandSender)) {
@@ -110,6 +126,11 @@ public boolean onCommand(CommandSender sender, Command command, String label, St
         return true;
     }
 
+    @Override
+    public void onDisable() {
+        PacketEvents.getAPI().terminate();
+    }
+
     @Override
     public String getMessage(String key) {
         return ChatColor.translateAlternateColorCodes('&', getConfig().getString(key));
@@ -128,8 +149,8 @@ private static boolean isPaperServer() {
         return classExists("com.destroystokyo.paper.PaperConfig");
     }
 
-    private boolean hasProtocolLib() {
-        return getServer().getPluginManager().getPlugin("ProtocolLib") != null;
+    private boolean hasPacketEvents() {
+        return getServer().getPluginManager().getPlugin("packetevents") != null;
     }
 
     private static boolean classExists(String className) {

bungeeguard-spigot/src/main/java/me/lucko/bungeeguard/spigot/listener/PacketEventsHandshakeListener.java

@@ -0,0 +1,91 @@
+package me.lucko.bungeeguard.spigot.listener;
+
+import com.github.retrooper.packetevents.PacketEvents;
+import com.github.retrooper.packetevents.event.PacketListener;
+import com.github.retrooper.packetevents.event.PacketListenerPriority;
+import com.github.retrooper.packetevents.event.PacketReceiveEvent;
+import com.github.retrooper.packetevents.wrapper.handshaking.client.WrapperHandshakingClientHandshake;
+import me.lucko.bungeeguard.backend.BungeeGuardBackend;
+import me.lucko.bungeeguard.backend.TokenStore;
+import me.lucko.bungeeguard.backend.listener.AbstractHandshakeListener;
+import me.lucko.bungeeguard.spigot.BungeeCordHandshake;
+import me.lucko.bungeeguard.spigot.BungeeGuardBackendPlugin;
+import org.bukkit.entity.Player;
+import org.bukkit.plugin.Plugin;
+
+import java.net.InetSocketAddress;
+import java.util.logging.Level;
+
+/**
+ * A handshake listener using PacketEvents.
+ */
+public class PacketEventsHandshakeListener extends AbstractHandshakeListener {
+
+    private static final int HANDSHAKE_PACKET_ID = 0x00; // ID for Handshake packets
+
+    public PacketEventsHandshakeListener(BungeeGuardBackend plugin, TokenStore tokenStore) {
+        super(plugin, tokenStore);
+    }
+
+    public void registerListener() {
+        PacketEvents.getAPI().getEventManager().registerListener(new HandshakeListener(), PacketListenerPriority.HIGHEST);
+    }
+
+    private final class HandshakeListener implements PacketListener {
+
+        @Override
+        public void onPacketReceive(PacketReceiveEvent event) {
+            if (event.getPacketId() != HANDSHAKE_PACKET_ID) {
+                return;
+            }
+
+            Player player = event.getPlayer();
+
+            WrapperHandshakingClientHandshake wrapperHandshakingClientHandshake = new WrapperHandshakingClientHandshake(event);
+            if (!wrapperHandshakingClientHandshake.getIntention().equals(WrapperHandshakingClientHandshake.ConnectionIntention.LOGIN)) {
+                return;
+            }
+
+            String handshake = wrapperHandshakingClientHandshake.readString(0);
+            BungeeCordHandshake decoded = BungeeCordHandshake.decodeAndVerify(handshake, PacketEventsHandshakeListener.this.tokenStore);
+
+            if (decoded instanceof BungeeCordHandshake.Fail) {
+                String ip = "null";
+                InetSocketAddress address = player.getAddress();
+                if (address != null) {
+                    ip = address.getHostString();
+                    if (ip.length() > 15) {
+                        ip = BungeeCordHandshake.encodeBase64(ip);
+                    }
+                }
+                BungeeCordHandshake.Fail fail = (BungeeCordHandshake.Fail) decoded;
+                BungeeGuardBackendPlugin.getInstance().getLogger().warning("Denying connection from " + ip + " - " + fail.describeConnection() + " - reason: " + fail.reason().name());
+
+                String kickMessage;
+                if (fail.reason() == BungeeCordHandshake.Fail.Reason.INVALID_HANDSHAKE) {
+                    kickMessage = PacketEventsHandshakeListener.this.noDataKickMessage;
+                } else {
+                    kickMessage = PacketEventsHandshakeListener.this.invalidTokenKickMessage;
+                }
+
+                try {
+                    closeConnection(player, kickMessage);
+                } catch (Exception e) {
+                    BungeeGuardBackendPlugin.getInstance().getLogger().log(Level.SEVERE, "An error occurred while closing connection for " + player, e);
+                }
+
+                // Prevent further processing by modifying the packet
+                wrapperHandshakingClientHandshake.writeString("null");
+                return;
+            }
+
+            // Successfully decoded and verified the handshake
+            BungeeCordHandshake.Success data = (BungeeCordHandshake.Success) decoded;
+            wrapperHandshakingClientHandshake.writeString(data.encode());
+        }
+    }
+
+    private static void closeConnection(Player player, String kickMessage) {
+        player.kickPlayer(kickMessage);
+    }
+}

bungeeguard-spigot/src/main/resources/plugin.yml

@@ -5,7 +5,7 @@ author: Luck
 load: STARTUP
 
 main: me.lucko.bungeeguard.spigot.BungeeGuardBackendPlugin
-softdepend: [ProtocolLib]
+softdepend: [packetevents]
 api-version: 1.13
 folia-supported: true
 

pom.xml

@@ -44,8 +44,12 @@
             <url>https://repo.papermc.io/repository/maven-public/</url>
         </repository>
         <repository>
-            <id>luck-repo</id>
-            <url>https://repo.lucko.me/</url>
+            <id>codemc-releases</id>
+            <url>https://repo.codemc.io/repository/maven-releases/</url>
+        </repository>
+        <repository>
+            <id>codemc-snapshots</id>
+            <url>https://repo.codemc.io/repository/maven-snapshots/</url>
         </repository>
     </repositories>