Update README.md

Refactoring AmbassadorConfig

README.md

@@ -3,7 +3,8 @@
 This is a Velocity plugin that makes it possible to host a modern Forge server behind a Velocity proxy!
 
 Unlike other solutions, this plugin does not require any special modifications to the backend server nor the client. (The player doesn't need to do anything)
-
+## Only for 1.13-1.20.1
+Velocity has now added built-in support for newer mc versions and therefore don't need Ambassador. You might still need PCF mod on the server-side, for more info please visit: https://github.com/adde0109/Proxy-Compatible-Forge
 ## How to get started:
 1. Download and install this plugin to your proxy.
 2. After starting the server, configure the plugin it to your liking using the config file found in the folder "Ambassador".
@@ -13,12 +14,13 @@ Unlike other solutions, this plugin does not require any special modifications t
 - https://github.com/caunt/BungeeForge (Legacy forwarding)
 
 ## Features
-* Server switching using kick to reset the client with configureble message and switch timeout.
-* ServerRedirect support for auto-reconnecting during switch.
-* Server switching using client mod for instant server switching: 
-https://github.com/Just-Chaldea/Forge-Client-Reset-Packet 
-1.18.2 and 1.19 fork:
-https://github.com/adde0109/Forge-Client-Reset-Packet
+* Server switching without any client side mod when the servers are similar. (Mods must match)
+* ServerRedirect support for server switching.
+* Server switching using Client Reset Packet Mod for instant server switching:
+  
+1.16.5: https://github.com/Just-Chaldea/Forge-Client-Reset-Packet
+
+1.18.2+: https://www.curseforge.com/minecraft/mc-mods/forge-client-reset-packet-forward
 
 ## Stuck on "Negotiating":
 This is an issue with Client Reset Packet Mod being partly incompatible with certain mods on the client. Please remove incompatible mods on the client if you have this issue. (Yes, this also includes client-side only mods.)

Velocity

@@ -1 +1 @@
-Subproject commit eb594fc799281ff418dc2c161c2d8a8eb0c89a19
+Subproject commit c3583e182ca6585e40d1eef0da8c18547c0b1bc1

build.gradle.kts

@@ -5,7 +5,7 @@ plugins {
 }
 
 group = "org.adde0109"
-version = "1.4.3-beta"
+version = "1.5.3-beta"
 
 repositories {
     mavenCentral()

src/main/java/org/adde0109/ambassador/Ambassador.java

@@ -19,14 +19,18 @@ import java.util.Map;
 import com.velocitypowered.api.proxy.server.RegisteredServer;
 import com.velocitypowered.proxy.VelocityServer;
 import com.velocitypowered.proxy.connection.MinecraftConnection;
+import com.velocitypowered.proxy.connection.client.ConnectedPlayer;
 import com.velocitypowered.proxy.network.ConnectionManager;
 import com.velocitypowered.proxy.protocol.StateRegistry;
+import com.velocitypowered.proxy.protocol.packet.DisconnectPacket;
 import com.velocitypowered.proxy.protocol.packet.brigadier.ArgumentIdentifier;
 import com.velocitypowered.proxy.protocol.packet.brigadier.ArgumentPropertyRegistry;
 import com.velocitypowered.proxy.protocol.packet.brigadier.ArgumentPropertySerializer;
 import io.netty.buffer.ByteBuf;
 import io.netty.channel.Channel;
 import io.netty.channel.ChannelInitializer;
+import net.kyori.adventure.text.Component;
+import net.kyori.adventure.text.minimessage.MiniMessage;
 import org.adde0109.ambassador.velocity.VelocityBackendChannelInitializer;
 import org.adde0109.ambassador.velocity.VelocityServerChannelInitializer;
 import org.adde0109.ambassador.velocity.VelocityEventHandler;
@@ -42,11 +46,11 @@ import java.util.concurrent.TimeUnit;
 import static com.velocitypowered.api.network.ProtocolVersion.MINECRAFT_1_19;
 import static com.velocitypowered.proxy.protocol.packet.brigadier.ArgumentIdentifier.mapSet;
 
-@Plugin(id = "ambassador", name = "Ambassador", version = "1.4.3-beta", authors = {"adde0109"})
+@Plugin(id = "ambassador", name = "Ambassador", version = "1.5.3-beta", authors = {"adde0109"})
 public class Ambassador {
 
   //Don't forget to update checkCompatibleVersion() when changing this value
-  private static final String minVelocityVersion = "velocity-3.2.0-SNAPSHOT-266";
+  private static final String minVelocityVersion = "velocity-3.3.0-SNAPSHOT-330";
 
   public ProxyServer server;
   public final Logger logger;
@@ -75,9 +79,9 @@ public class Ambassador {
   boolean checkCompatibleVersion() {
     //Update this when changing minVelocityVersion
     try {
-      MinecraftConnection.class.getDeclaredMethod("setActiveSessionHandler", StateRegistry.class);
-    } catch (NoSuchMethodException e) {
-      return false;
+      Class.forName("com.velocitypowered.proxy.protocol.packet.DisconnectPacket");
+    } catch (ClassNotFoundException e) {
+        throw new RuntimeException(e);
     }
       return true;
   }
@@ -96,7 +100,6 @@ public class Ambassador {
 
       Path configPath = dataDirectory.resolve("Ambassador.toml");
       config = AmbassadorConfig.read(configPath);
-      config.validate();
 
       inject();
 
@@ -111,7 +114,6 @@ public class Ambassador {
     try {
       Path configPath = dataDirectory.resolve("Ambassador.toml");
       final AmbassadorConfig newconfig = AmbassadorConfig.read(configPath);
-      newconfig.validate();
 
       config = newconfig;
     } catch (Exception e) {
@@ -154,6 +156,16 @@ public class Ambassador {
     return TEMPORARY_FORCED;
   }
 
+  public void reconnectSwitchPlayer(ConnectedPlayer player) {
+    TEMPORARY_FORCED.put(player.getUsername(), player.getConnectionInFlight().getServer(),
+            config.getServerSwitchCancellationTime(), TimeUnit.SECONDS);
+
+    MiniMessage mm = MiniMessage.miniMessage();
+    Component parsed = mm.deserialize(config.getKickReconnectMessageString());
+
+    player.disconnect(parsed);
+  }
+
   private void initMetrics() {
     Metrics metrics = metricsFactory.make(this, 15655);
   }

src/main/java/org/adde0109/ambassador/AmbassadorConfig.java

@@ -7,36 +7,43 @@ import net.kyori.adventure.text.serializer.gson.GsonComponentSerializer;
 import net.kyori.adventure.text.serializer.legacy.LegacyComponentSerializer;
 import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
 
+import java.io.IOException;
 import java.net.URL;
+import java.nio.file.Files;
 import java.nio.file.Path;
 
 public class AmbassadorConfig {
 
-
     @Expose
-  private String disconnectResetMessage = "Please reconnect";
-
-  @Expose
-  private int serverSwitchCancellationTime = 120;
+    private int serverSwitchCancellationTime = 30;
 
     @Expose
     private boolean silenceWarnings = false;
+    @Expose
+    private boolean bypassRegistryCheck = false;
+    @Expose
+    private boolean bypassModCheck = false;
 
-  private net.kyori.adventure.text.@MonotonicNonNull Component messageAsAsComponent;
+    @Expose
+    private boolean debugMode = false;
 
-  private AmbassadorConfig(String kickResetMessage, int serverSwitchCancellationTime, boolean silenceWarnings) {
-    this.disconnectResetMessage = kickResetMessage;
-    this.serverSwitchCancellationTime = serverSwitchCancellationTime;
+    @Expose
+    private boolean enableKickReset = false;
+
+    @Expose
+    private String kickReconnectMessageString = "<red>Please reconnect.</red>";
+
+    private AmbassadorConfig(boolean silenceWarnings, boolean bypassRegistryCheck, boolean bypassModCheck,
+                             boolean debugMode, boolean enableKickReset, String kickReconnectMessageString) {
         this.silenceWarnings = silenceWarnings;
-  };
-
-  public void validate() {
-    if (serverSwitchCancellationTime <= 0) {
-      throw new InvalidValueException("'server-switch-cancellation-time' can't be less than nor equal to zero: server-switch-cancellation-time=" + serverSwitchCancellationTime);
-    }
+        this.bypassRegistryCheck = bypassRegistryCheck;
+        this.bypassModCheck = bypassModCheck;
+        this.debugMode = debugMode;
+        this.enableKickReset = enableKickReset;
+        this.kickReconnectMessageString = kickReconnectMessageString;
     }
 
-  public static AmbassadorConfig read(Path path) {
+    public static AmbassadorConfig read(Path path) throws IOException {
         URL defaultConfigLocation = AmbassadorConfig.class.getClassLoader()
                 .getResource("default-ambassador.toml");
         if (defaultConfigLocation == null) {
@@ -58,28 +65,41 @@ public class AmbassadorConfig {
             configVersion = 1.0;
         }
 
-    if (configVersion < 1.1) {
-      config.set("silence-warnings", false);
-      config.set("config-version", "1.2");
-    }
-
-    String kickResetMessage = config.getOrElse("disconnect-reset-message", "Please reconnect");
-    int serverSwitchCancellationTime = config.getIntOrElse("server-switch-cancellation-time", 120);
-
         boolean silenceWarnings = config.getOrElse("silence-warnings", false);
 
-    return new AmbassadorConfig(kickResetMessage, serverSwitchCancellationTime, silenceWarnings);
+        int serverSwitchCancellationTime = config.getOrElse("serverRedirectTimeout", 30);
+
+        boolean bypassRegistryCheck = config.getOrElse("bypass-registry-checks", false);
+
+        boolean bypassModCheck = config.getOrElse("bypass-mod-checks", false);
+
+        boolean debugMode = config.getOrElse("debug-mode", false);
+
+        String kickReconnectMessageString = config.getOrElse("disconnect-reset-message",
+                config.getOrElse("reconnect-message", "<red>Please reconnect.</red>"));
+
+        //Upgrade config
+        if (configVersion <= 2.0) {
+            Files.delete(path);
+            config = CommentedFileConfig.builder(path)
+                    .defaultData(defaultConfigLocation)
+                    .autosave()
+                    .preserveInsertionOrder()
+                    .sync()
+                    .build();
+            config.load();
+            config.set("silence-warnings", silenceWarnings);
+            config.set("serverRedirectTimeout", serverSwitchCancellationTime);
+            config.set("bypass-registry-checks", bypassRegistryCheck);
+            config.set("bypass-mod-checks", bypassModCheck);
+            config.set("debug-mode", debugMode);
+            config.set("reconnect-message", kickReconnectMessageString);
         }
 
-  public net.kyori.adventure.text.Component getDisconnectResetMessage() {
-    if (messageAsAsComponent == null) {
-      if (disconnectResetMessage.startsWith("{")) {
-        messageAsAsComponent = GsonComponentSerializer.gson().deserialize(disconnectResetMessage);
-      } else {
-        messageAsAsComponent = LegacyComponentSerializer.legacyAmpersand().deserialize(disconnectResetMessage);
-      }
-    }
-    return messageAsAsComponent;
+        boolean enableKickReset = config.getOrElse("enable-kick-reset", false);
+
+        return new AmbassadorConfig(silenceWarnings, bypassRegistryCheck, bypassModCheck,
+                debugMode, enableKickReset, kickReconnectMessageString);
     }
 
     public int getServerSwitchCancellationTime() {
@@ -89,4 +109,24 @@ public class AmbassadorConfig {
     public boolean isSilenceWarnings() {
         return silenceWarnings;
     }
+
+    public boolean isBypassRegistryCheck() {
+        return bypassRegistryCheck;
+    }
+
+    public boolean isBypassModCheck() {
+        return bypassModCheck;
+    }
+
+    public boolean isDebugMode() {
+        return debugMode;
+    }
+
+    public boolean isEnableKickReset() {
+        return enableKickReset;
+    }
+
+    public String getKickReconnectMessageString() {
+        return kickReconnectMessageString;
+    }
 }

src/main/java/org/adde0109/ambassador/forge/ForgeHandshake.java

@@ -0,0 +1,42 @@
+package org.adde0109.ambassador.forge;
+
+import org.adde0109.ambassador.forge.packet.Context;
+import org.adde0109.ambassador.forge.packet.GenericForgeLoginWrapperPacket;
+import org.adde0109.ambassador.forge.packet.ModListReplyPacket;
+import org.adde0109.ambassador.forge.packet.RegistryPacket;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.zip.Adler32;
+import java.util.zip.Checksum;
+
+public class ForgeHandshake {
+    private ModListReplyPacket modListReplyPacket;
+    private final Map<String, Long> registries = new HashMap<>();
+    public GenericForgeLoginWrapperPacket<Context.ClientContext> zetaFlagsPacket;
+
+    public ForgeHandshake() {
+    }
+
+    public ModListReplyPacket getModListReplyPacket() {
+        return modListReplyPacket;
+    }
+
+    public void setModListReplyPacket(ModListReplyPacket modListReplyPacket) {
+        this.modListReplyPacket = modListReplyPacket;
+    }
+
+    public void addRegistry(RegistryPacket packet) {
+        Checksum registryChecksum = new Adler32();
+        registryChecksum.update(packet.getSnapshot());
+        registries.put(packet.getRegistryName(), registryChecksum.getValue());
+    }
+
+    public Map<String, Long> getRegistries() {
+        return registries;
+    }
+
+    public boolean isCompatible(ForgeHandshake handshake) {
+        return this.registries.equals(handshake.registries);
+    }
+}

src/main/java/org/adde0109/ambassador/forge/ForgeHandshakeUtils.java

@@ -3,6 +3,12 @@ package org.adde0109.ambassador.forge;
 import com.google.common.io.ByteArrayDataInput;
 import com.google.common.io.ByteArrayDataOutput;
 import com.google.common.io.ByteStreams;
+import com.velocitypowered.proxy.protocol.ProtocolUtils;
+import io.netty.buffer.ByteBuf;
+import io.netty.buffer.Unpooled;
+import org.adde0109.ambassador.forge.packet.Context;
+import org.adde0109.ambassador.forge.packet.GenericForgeLoginWrapperPacket;
+import org.adde0109.ambassador.forge.packet.IForgeLoginWrapperPacket;
 
 import java.nio.charset.StandardCharsets;
 
@@ -110,4 +116,61 @@ public class ForgeHandshakeUtils {
     stream.write(dataAndPacketId);
     return stream.toByteArray();
   }
+
+  public static class ThirdPartyRegistryUtils {
+
+    static enum ThirdPartyChannel {
+      SILENTGEAR_NETWORK {
+        @Override
+        public IForgeLoginWrapperPacket<Context.ClientContext> generateResponsePacket(Context.ClientContext context, ForgeHandshake completed) {
+          return new ACKPacket(context, 3);
+        }
+      },
+      ZETA_MAIN {
+        @Override
+        public IForgeLoginWrapperPacket<Context.ClientContext> generateResponsePacket(Context.ClientContext context, ForgeHandshake completed) {
+          return new GenericForgeLoginWrapperPacket<Context.ClientContext>(completed.zetaFlagsPacket.getContent(), context);
+        }
+      };
+      abstract public IForgeLoginWrapperPacket<Context.ClientContext> generateResponsePacket(Context.ClientContext context, ForgeHandshake completed);
+    }
+
+    static boolean isThirdPartyPacket(GenericForgeLoginWrapperPacket<Context> packet) {
+      try {
+        Enum.valueOf(ThirdPartyChannel.class,
+                packet.getContext().getChannelName().replace(':', '_').toUpperCase());
+        return true;
+      } catch (IllegalArgumentException e) {
+        return false;
+      }
+    }
+
+    static ThirdPartyChannel getThirdPartyChannel(GenericForgeLoginWrapperPacket<Context> packet) {
+      return Enum.valueOf(ThirdPartyChannel.class,
+              packet.getContext().getChannelName().replace(':', '_').toUpperCase());
+    }
+
+    static class ACKPacket implements IForgeLoginWrapperPacket<Context.ClientContext> {
+
+      private final Context.ClientContext context;
+      private final int packetID;
+      ACKPacket(Context.ClientContext context, int packetID) {
+        this.context = context;
+        this.packetID = packetID;
+      }
+
+      public ByteBuf encode() {
+        ByteBuf buf = Unpooled.buffer();
+
+        ProtocolUtils.writeVarInt(buf, packetID);
+
+        return buf;
+      }
+
+      @Override
+      public Context.ClientContext getContext() {
+        return context;
+      }
+    }
+  }
 }

src/main/java/org/adde0109/ambassador/forge/ShadowHandshakeReceiver.java

@@ -0,0 +1,70 @@
+package org.adde0109.ambassador.forge;
+
+import com.velocitypowered.proxy.connection.client.ConnectedPlayer;
+import org.adde0109.ambassador.forge.packet.*;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.zip.Adler32;
+import java.util.zip.Checksum;
+
+public class ShadowHandshakeReceiver {
+
+  private final ConnectedPlayer player;
+  private final ModListReplyPacket modListReplyPacket;
+  private final Map<String, Long> registries;
+
+  private ShadowHandshakeReceiver(ConnectedPlayer player, ModListReplyPacket modListReplyPacket,
+                                 Map<String, Long> registries) {
+    this.player = player;
+    this.modListReplyPacket = modListReplyPacket;
+    this.registries = registries;
+  }
+
+  void handle(IForgeLoginWrapperPacket packet) throws IncompatibleHandshake {
+
+  }
+
+  void handle(ModListPacket packet) throws IncompatibleHandshake {
+
+    //player.getConnection().write();
+  }
+
+  void handle(RegistryPacket packet) throws IncompatibleHandshake {
+
+    player.getConnection().write(new ACKPacket(Context.fromContext(packet.getContext(), true)));
+  }
+  void handle(ConfigDataPacket packet) throws IncompatibleHandshake {
+
+    player.getConnection().write(new ACKPacket(Context.fromContext(packet.getContext(), true)));
+  }
+
+  static class Builder {
+
+    ConnectedPlayer player;
+    ModListReplyPacket modListReplyPacket;
+    Map<String, Long> registries = new HashMap<>();
+
+    void addModListPacket(ModListPacket packet) {
+
+    }
+    void setModListReplyPacket(ModListReplyPacket packet) {
+      this.modListReplyPacket = packet;
+    }
+
+    void addRegistryPacket(RegistryPacket packet) {
+      Checksum registryChecksum = new Adler32();
+      registryChecksum.update(packet.getSnapshot());
+      registries.put(packet.getRegistryName(), registryChecksum.getValue());
+    }
+
+    ShadowHandshakeReceiver build() {
+      return new ShadowHandshakeReceiver(player, modListReplyPacket, registries);
+    }
+  }
+
+
+  class IncompatibleHandshake extends Throwable {
+
+  }
+}

src/main/java/org/adde0109/ambassador/forge/VelocityForgeBackendConnectionPhase.java

@@ -6,19 +6,21 @@ import com.velocitypowered.proxy.connection.backend.VelocityServerConnection;
 import com.velocitypowered.proxy.connection.client.ConnectedPlayer;
 import com.velocitypowered.proxy.network.Connections;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
-import com.velocitypowered.proxy.protocol.StateRegistry;
-import com.velocitypowered.proxy.protocol.packet.AvailableCommands;
-import com.velocitypowered.proxy.protocol.packet.LoginPluginMessage;
-import com.velocitypowered.proxy.protocol.packet.PluginMessage;
-import io.netty.buffer.ByteBuf;
+import com.velocitypowered.proxy.protocol.packet.AvailableCommandsPacket;
+import com.velocitypowered.proxy.protocol.packet.PluginMessagePacket;
+import net.kyori.adventure.text.Component;
+import org.adde0109.ambassador.Ambassador;
+import org.adde0109.ambassador.forge.packet.*;
 import org.adde0109.ambassador.forge.pipeline.CommandDecoderErrorCatcher;
-import org.adde0109.ambassador.forge.pipeline.ForgeLoginWrapperDecoder;
+
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.CountDownLatch;
 
 public enum VelocityForgeBackendConnectionPhase implements BackendConnectionPhase {
-  NOT_STARTED() {
+  NOT_STARTED {
     @Override
     VelocityForgeBackendConnectionPhase nextPhase() {
-      return WAITING_FOR_ACK;
+      return IN_PROGRESS;
     }
 
     @Override
@@ -27,7 +29,7 @@ public enum VelocityForgeBackendConnectionPhase implements BackendConnectionPhas
       return true;
     }
   },
-  WAITING_FOR_ACK() {
+  IN_PROGRESS {
     @Override
     public void onLoginSuccess(VelocityServerConnection serverCon, ConnectedPlayer player) {
       serverCon.setConnectionPhase(VelocityForgeBackendConnectionPhase.COMPLETE);
@@ -47,43 +49,119 @@ public enum VelocityForgeBackendConnectionPhase implements BackendConnectionPhas
     }
   },
 
-  COMPLETE() {
+  COMPLETE {
     @Override
     public boolean consideredComplete() {
       return true;
     }
   };
 
-
+  public ForgeHandshake handshake = new ForgeHandshake();
+  CountDownLatch remainingRegistries;
 
   VelocityForgeBackendConnectionPhase() {
   }
 
-  public void handle(VelocityServerConnection server, ConnectedPlayer player, LoginPluginMessage message) {
-
+  public void handle(VelocityServerConnection server, ConnectedPlayer player, IForgeLoginWrapperPacket<Context> message) {
     VelocityForgeBackendConnectionPhase newPhase = getNewPhase(server,message);
 
     server.setConnectionPhase(newPhase);
 
-    //Reset client if not ready to receive new handshake
+    //Forge -> Forge
+
     VelocityForgeClientConnectionPhase clientPhase = (VelocityForgeClientConnectionPhase) player.getPhase();
-    if (clientPhase != VelocityForgeClientConnectionPhase.NOT_STARTED) {
-      clientPhase.resetConnectionPhase(player);
-      if (clientPhase == VelocityForgeClientConnectionPhase.COMPLETE)
-      {
-        //Do not continue if the client can't reset.
+
+
+    if (!player.isActive()) {
       return;
     }
+
+    if (!clientPhase.consideredComplete()) {
+      //Initial Forge
+      if (message instanceof ModListPacket modListPacket) {
+        clientPhase.forgeHandshake = new ForgeHandshake();
+      }
+      if (message instanceof RegistryPacket registryPacket) {
+        clientPhase.forgeHandshake.addRegistry(registryPacket);
       }
-    message.retain();
       player.getConnection().write(message);
+    } else {
+      //Reset client if not ready to receive new handshake
+      if (clientPhase.getResetType() == VelocityForgeClientConnectionPhase.ClientResetType.CRP ||
+              clientPhase.getResetType() == VelocityForgeClientConnectionPhase.ClientResetType.SR) {
+        clientPhase.resetConnectionPhase(player);
+        player.getConnection().write(message);
+        return;
+      }
+
+      if (clientPhase.forgeHandshake.getModListReplyPacket() == null) {
+        //We have nothing to respond with during this handshake. Unable to proceed.
+        if (Ambassador.getInstance().config.isEnableKickReset()) {
+          //Kick-reset
+          Ambassador.getInstance().reconnectSwitchPlayer(player);
+        } else {
+          Ambassador.getInstance().logger.error("Unable for {} to switch servers. Vanilla({}) -> Forge({}) switch " +
+                          "without client side mod or kick-reset enabled is not yet supported!",
+                  player.getGameProfile().getName(), player.getConnectedServer().getServerInfo().getName(),
+                  server.getServerInfo().getName());
+          server.disconnect();
+        }
+        return;
+      }
+
+      if (message instanceof ModListPacket modListPacket) {
+        remainingRegistries = new CountDownLatch(modListPacket.getRegistries().size());
+
+        if (Ambassador.getInstance().config.isDebugMode())
+          player.sendMessage(Component.text("Expecting " + modListPacket.getRegistries().size() +
+                  " packets from server " + server.getServer().getServerInfo().getName()));
+
+        long time = System.currentTimeMillis();
+        CompletableFuture.runAsync(() -> {
+          try {
+            remainingRegistries.await();
+          } catch (InterruptedException e) {
+            throw new RuntimeException(e);
+          }
+        }).thenAcceptAsync((v) -> {
+
+          if(Ambassador.getInstance().config.isDebugMode()) {
+            player.sendMessage(Component.text("Handshake took: " + (System.currentTimeMillis()-time) + " ms"));
+            player.sendMessage(Component.text("Avg packet time" +
+                    (System.currentTimeMillis()-time)/modListPacket.getRegistries().size() + " ms"));
+          }
+
+          if (Ambassador.getInstance().config.isBypassRegistryCheck() ||
+                  clientPhase.forgeHandshake.isCompatible(handshake)) {
+            server.ensureConnected().write(clientPhase.forgeHandshake.getModListReplyPacket());
+          } else if (Ambassador.getInstance().config.isEnableKickReset()) {
+            //Kick-reset
+            Ambassador.getInstance().reconnectSwitchPlayer(player);
+          } else {
+            Ambassador.getInstance().logger.error("Unable to switch due to the registries of " +
+                    server.getServer().getServerInfo().getName() + " being different from the registries of " +
+                    player.getConnectedServer().getServer().getServerInfo().getName());
+            server.disconnect();
+          }
+        }, server.ensureConnected().eventLoop());
+      } else if (message instanceof RegistryPacket registryPacket) {
+        server.getConnection().write(new ACKPacket(Context.fromContext(message.getContext(), true)));
+        handshake.addRegistry(registryPacket);
+        remainingRegistries.countDown();
+      } else if (message instanceof ConfigDataPacket) {
+        server.getConnection().write(new ACKPacket(Context.fromContext(message.getContext(), true)));
+      } else if (message instanceof GenericForgeLoginWrapperPacket<Context> packet
+              && ForgeHandshakeUtils.ThirdPartyRegistryUtils.isThirdPartyPacket(packet)) {
+          server.getConnection().write(
+                  ForgeHandshakeUtils.ThirdPartyRegistryUtils.getThirdPartyChannel(packet).
+                          generateResponsePacket(
+                                  Context.ClientContext.fromContext(packet.getContext(), true),
+                                  clientPhase.forgeHandshake));
+      }
+    }
     //Forge server
     //To avoid unnecessary resets, we wait until we get the handshake even if we know that we should
     //reset because that the previous server was Forge.
-
-    ForgeLoginWrapperDecoder decoder = (ForgeLoginWrapperDecoder) player.getConnection()
-            .getChannel().pipeline().get(ForgeConstants.FORGE_HANDSHAKE_DECODER);
-    decoder.registerLoginWrapperID(message.getId());
   }
 
   public void onLoginSuccess(VelocityServerConnection serverCon, ConnectedPlayer player) {
@@ -97,7 +175,7 @@ public enum VelocityForgeBackendConnectionPhase implements BackendConnectionPhas
   }
 
   private VelocityForgeBackendConnectionPhase getNewPhase(VelocityServerConnection serverConnection,
-                                                       LoginPluginMessage packet) {
+                                                       IForgeLoginWrapperPacket<Context> packet) {
     VelocityForgeBackendConnectionPhase phaseToTransitionTo = nextPhase();
     if (phaseToTransitionTo != this) {
       phaseToTransitionTo.onTransitionToNewPhase(serverConnection);
@@ -106,9 +184,9 @@ public enum VelocityForgeBackendConnectionPhase implements BackendConnectionPhas
   }
 
   @Override
-  public boolean handle(VelocityServerConnection server, ConnectedPlayer player, PluginMessage message) {
+  public boolean handle(VelocityServerConnection server, ConnectedPlayer player, PluginMessagePacket message) {
     if (message.getChannel().equals("ambassador:commands")) {
-      AvailableCommands packet = new AvailableCommands();
+      AvailableCommandsPacket packet = new AvailableCommandsPacket();
       packet.decode(message.content(), ProtocolUtils.Direction.CLIENTBOUND,server.getConnection().getProtocolVersion());
       server.getConnection().getActiveSessionHandler().handle(packet);
       return true;

src/main/java/org/adde0109/ambassador/forge/VelocityForgeClientConnectionPhase.java

@@ -10,15 +10,16 @@ import com.velocitypowered.proxy.connection.client.ConnectedPlayer;
 import com.velocitypowered.proxy.network.Connections;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
 import com.velocitypowered.proxy.protocol.StateRegistry;
-import com.velocitypowered.proxy.protocol.packet.LoginPluginMessage;
-import com.velocitypowered.proxy.protocol.packet.PluginMessage;
+import com.velocitypowered.proxy.protocol.packet.LoginPluginMessagePacket;
+import com.velocitypowered.proxy.protocol.packet.PluginMessagePacket;
 import io.netty.buffer.ByteBuf;
 import io.netty.buffer.Unpooled;
 import net.kyori.adventure.text.Component;
 import org.adde0109.ambassador.Ambassador;
+import org.adde0109.ambassador.forge.packet.Context;
+import org.adde0109.ambassador.forge.packet.GenericForgeLoginWrapperPacket;
 import org.adde0109.ambassador.forge.packet.IForgeLoginWrapperPacket;
 import org.adde0109.ambassador.forge.packet.ModListReplyPacket;
-import org.adde0109.ambassador.forge.pipeline.ForgeLoginWrapperDecoder;
 import org.adde0109.ambassador.velocity.client.FML2CRPMResetCompleteDecoder;
 import org.adde0109.ambassador.velocity.client.OutboundSuccessHolder;
 import org.adde0109.ambassador.velocity.client.ClientPacketQueue;
@@ -35,54 +36,15 @@ public enum VelocityForgeClientConnectionPhase implements ClientConnectionPhase
     }
 
     @Override
-    public void resetConnectionPhase(ConnectedPlayer player) {
-      RESETTABLE.resetConnectionPhase(player);
+    public void complete(ConnectedPlayer player) {
+      //When no handshake has taken place.
+      //Test if the client supports CRP.
+      ClientResetType.CRP.doReset(player);
     }
     },
   IN_PROGRESS {
   },
-  RESETTABLE {
-    @Override
-    void onTransitionToNewPhase(ConnectedPlayer player) {
-      //Plugins may now send packets to client
-      player.getConnection().getChannel().pipeline().remove(ForgeConstants.PLUGIN_PACKET_QUEUE);
-      ((VelocityServer) Ambassador.getInstance().server).registerConnection(player);
-    }
-
-    @Override
-    public void resetConnectionPhase(ConnectedPlayer player) {
-      MinecraftConnection connection = player.getConnection();
-
-      //There is no going back even if the handshake fails. No reason to still be connected.
-      if (player.getConnectedServer() != null) {
-        player.getConnectedServer().disconnect();
-        player.setConnectedServer(null);
-      }
-      //Don't handle anything from the server until the reset has completed.
-      //player.getConnectionInFlight().getConnection().getChannel().config().setAutoRead(false);
-
-      if (connection.getState() == StateRegistry.PLAY || connection.getState() == StateRegistry.CONFIG) {
-        connection.write(new PluginMessage("fml:handshake", Unpooled.wrappedBuffer(ForgeHandshakeUtils.generatePluginResetPacket())));
-        connection.setState(StateRegistry.LOGIN);
-      } else {
-        connection.write(new LoginPluginMessage(98,"fml:loginwrapper", Unpooled.wrappedBuffer(ForgeHandshakeUtils.generateResetPacket())));
-      }
-
-      //Prepare to receive reset ACK
-      connection.getChannel().pipeline().addBefore(Connections.MINECRAFT_DECODER,
-              ForgeConstants.RESET_LISTENER, new FML2CRPMResetCompleteDecoder());
-
-      //Transition
-      player.setPhase(WAITING_RESET);
-      WAITING_RESET.onTransitionToNewPhase(player);
-    }
-
-    @Override
-    public boolean consideredComplete() {
-      return true;
-    }
-  },
-  WAITING_RESET {
+  WAITING_RESET() {
     @Override
     void onTransitionToNewPhase(ConnectedPlayer player) {
       //We unregister so no plugin sees this client while the client is being reset.
@@ -96,7 +58,8 @@ public enum VelocityForgeClientConnectionPhase implements ClientConnectionPhase
 
     @Override
     public boolean handle(ConnectedPlayer player, IForgeLoginWrapperPacket msg, VelocityServerConnection server) {
-      if (msg.getId() == 98) {
+      if (msg.getContext().getResponseID() == 98) {
+        //Reset complete
         player.getConnection().getChannel().pipeline().remove(ForgeConstants.RESET_LISTENER);
         player.setPhase(NOT_STARTED);
 
@@ -104,7 +67,10 @@ public enum VelocityForgeClientConnectionPhase implements ClientConnectionPhase
 
         if (!(server.getConnection().getType() instanceof ForgeFMLConnectionType)) {
           // -> vanilla
-          complete(player, msg.getSuccess());
+          complete(player, ((Context.ClientContext) msg.getContext()).success() ? ClientResetType.CRP : null);
+        }
+
+        if (player.getConnectionInFlight() != null) {
           player.getConnectionInFlight().getConnection().getChannel().config().setAutoRead(true);
         }
 
@@ -115,8 +81,15 @@ public enum VelocityForgeClientConnectionPhase implements ClientConnectionPhase
     }
   },
   COMPLETE {
+
+    private ClientResetType resetType = ClientResetType.UNKNOWN;
     @Override
     void onTransitionToNewPhase(ConnectedPlayer player) {
+      //Send Login Success to client
+      MinecraftConnection connection = player.getConnection();
+      ((OutboundSuccessHolder) connection.getChannel().pipeline().get(ForgeConstants.SERVER_SUCCESS_LISTENER))
+              .sendPacket();
+      connection.setState(StateRegistry.PLAY);
       //Plugins may now send packets to client
       player.getConnection().getChannel().pipeline().remove(ForgeConstants.PLUGIN_PACKET_QUEUE);
       ((VelocityServer) Ambassador.getInstance().server).registerConnection(player);
@@ -124,39 +97,49 @@ public enum VelocityForgeClientConnectionPhase implements ClientConnectionPhase
 
     @Override
     public void resetConnectionPhase(ConnectedPlayer player) {
-      Ambassador.getTemporaryForced().put(player.getUsername(), player.getConnectionInFlight().getServer(),
-              Ambassador.getInstance().config.getServerSwitchCancellationTime(), TimeUnit.SECONDS);
-      //Disconnect - Reset
-      if(player.getModInfo().isPresent()
-              && player.getModInfo().get().getMods().stream().anyMatch((mod -> mod.getId().equals("serverredirect")
-              || mod.getId().equals("srvredirect:red")))
-              && player.getVirtualHost().isPresent()) {
-        ByteBuf buf = Unpooled.buffer();
-        ProtocolUtils.writeVarInt(buf, 0);
-        buf.writeBytes((player.getVirtualHost().get().getHostName() + ":"
-                + player.getVirtualHost().get().getPort()).getBytes(StandardCharsets.UTF_8));
-        player.getConnection().write(new PluginMessage("srvredirect:red", buf));
-      } else {
-        player.disconnect(Ambassador.getInstance().config.getDisconnectResetMessage());
-      }
+      getResetType().doReset(player);
     }
 
     @Override
     public boolean consideredComplete() {
       return true;
     }
+
+    @Override
+    public void complete(ConnectedPlayer player) {
+      if (Ambassador.getInstance().config.isDebugMode()) {
+        player.sendMessage(Component.text("Not resetting"));
+      }
+    }
+
+    @Override
+    void setResetType(ConnectedPlayer player, ClientResetType resetType) {
+      this.resetType = resetType;
+      if (Ambassador.getInstance().config.isDebugMode()) {
+        player.sendMessage(Component.text("Reset type: " + this.resetType.toString()));
+      }
+    }
+
+    @Override
+    public ClientResetType getResetType() {
+      return resetType;
+    }
   };
 
-  public ModListReplyPacket clientModList;
+  //TODO: Make a new class that's linked to each player with these fields instead of having them in this phase class
+  public ForgeHandshake forgeHandshake = new ForgeHandshake();
 
-  public boolean handle(ConnectedPlayer player, IForgeLoginWrapperPacket msg, VelocityServerConnection server) {
-    player.setPhase(nextPhase());
+  public boolean handle(ConnectedPlayer player, IForgeLoginWrapperPacket<Context.ClientContext> msg, VelocityServerConnection server) {
+
+    if (msg.getContext().getChannelName().equals("zeta:main")) {
+      forgeHandshake.zetaFlagsPacket = (GenericForgeLoginWrapperPacket<Context.ClientContext>) msg;
+    }
 
     if (msg instanceof ModListReplyPacket replyPacket) {
       ModInfo modInfo = new ModInfo("FML2", replyPacket.getMods().stream().map(
               (v) -> new ModInfo.Mod(v,"1")).toList());
       player.setModInfo(modInfo);
-      this.clientModList = replyPacket;
+      forgeHandshake.setModListReplyPacket(replyPacket);
       if (!(server.getConnection().getType() instanceof ForgeFMLConnectionType)) {
         complete(player);
         player.getConnectionInFlight().getConnection().getChannel().config().setAutoRead(true);
@@ -165,46 +148,29 @@ public enum VelocityForgeClientConnectionPhase implements ClientConnectionPhase
       replyPacket.getChannels().put(MinecraftChannelIdentifier.from("ambassador:commands"),"1");
     }
 
-    player.getConnectionInFlight().getConnection().write(msg.encode());
+    player.getConnectionInFlight().getConnection().write(msg);
+
+    player.setPhase(nextPhase());
+    nextPhase().forgeHandshake = this.forgeHandshake;
+
     return true;
   }
-
-  public void sendVanillaModlist(ConnectedPlayer player) {
-    player.getConnection().write(new LoginPluginMessage(0, "fml:loginwrapper",
-            Unpooled.wrappedBuffer(player.getConnection().getType() == ForgeConstants.ForgeFML3 ?
-                    ForgeHandshakeUtils.emptyModlistFML3 : ForgeHandshakeUtils.emptyModlistFML2)));
-
-    ForgeLoginWrapperDecoder decoder = (ForgeLoginWrapperDecoder) player.getConnection()
-            .getChannel().pipeline().get(ForgeConstants.FORGE_HANDSHAKE_DECODER);
-    decoder.registerLoginWrapperID(0);
-  }
-
   public void complete(ConnectedPlayer player) {
-    complete(player, isResettable(player));
+    complete(player, null);
   }
 
-  public void complete(ConnectedPlayer player, boolean resettable) {
-    MinecraftConnection connection = player.getConnection();
-    ((OutboundSuccessHolder) connection.getChannel().pipeline().get(ForgeConstants.SERVER_SUCCESS_LISTENER))
-            .sendPacket();
-    connection.setState(StateRegistry.PLAY);
-
-    if (resettable) {
-      player.setPhase(RESETTABLE);
-      RESETTABLE.onTransitionToNewPhase(player);
-      RESETTABLE.clientModList = clientModList;
-    } else {
+  public void complete(ConnectedPlayer player, ClientResetType resetType) {
+    //Change phase to COMPLETE
     player.setPhase(COMPLETE);
     COMPLETE.onTransitionToNewPhase(player);
-      COMPLETE.clientModList = clientModList;
-    }
+    COMPLETE.forgeHandshake = forgeHandshake;
+    if (resetType != null) {
+      COMPLETE.setResetType(player, resetType);
     }
 
-  private boolean isResettable(ConnectedPlayer player) {
-    if (player.getModInfo().isPresent()) {
-      return player.getModInfo().get().getMods().stream().anyMatch((mod -> mod.getId().equals("clientresetpacket")));
+    if (Ambassador.getInstance().config.isDebugMode()) {
+      player.sendMessage(Component.text("Forge handshake complete"));
     }
-    return false;
   }
 
   void onTransitionToNewPhase(ConnectedPlayer player) {
@@ -220,5 +186,82 @@ public enum VelocityForgeClientConnectionPhase implements ClientConnectionPhase
     return false;
   }
 
-
+  public ClientResetType getResetType() {
+    return COMPLETE.getResetType();
+  }
+
+  private ClientResetType getResetType(ConnectedPlayer player) {
+    if (Ambassador.getInstance().config.isDebugMode()) {
+      player.sendMessage(Component.text("Scanning modlist for client reset mods"));
+    }
+    if (player.getModInfo().isPresent()) {
+      if (player.getModInfo().get().getMods().stream().anyMatch((mod -> mod.getId().equals("clientresetpacket")))) {
+        return ClientResetType.CRP;
+      } else if (Ambassador.getInstance().config.getServerSwitchCancellationTime() >= 0 &&
+              player.getModInfo().get().getMods().stream().anyMatch((mod -> mod.getId().equals("serverredirect")
+                      || mod.getId().equals("srvredirect:red")))
+              && player.getVirtualHost().isPresent()) {
+        return ClientResetType.SR;
+      }
+    }
+    return ClientResetType.NONE;
+  }
+
+  void setResetType(ConnectedPlayer player, ClientResetType resetType) {
+    COMPLETE.setResetType(player, resetType);
+  }
+  public void updateResetType(ConnectedPlayer player) {
+    COMPLETE.setResetType(player, getResetType(player));
+  }
+
+  public enum ClientResetType {
+    UNKNOWN,
+    NONE,
+    CRP {
+      @Override
+      void doReset(ConnectedPlayer player) {
+        MinecraftConnection connection = player.getConnection();
+
+        //There is no going back even if the handshake fails. No reason to still be connected.
+        if (player.getConnectedServer() != null) {
+          player.getConnectedServer().disconnect();
+          player.setConnectedServer(null);
+        }
+        //Don't handle anything from the server until the reset has completed.
+        if (player.getConnectionInFlight() != null) {
+          player.getConnectionInFlight().getConnection().getChannel().config().setAutoRead(false);
+        }
+
+        if (connection.getState() == StateRegistry.PLAY || connection.getState() == StateRegistry.CONFIG) {
+          connection.write(new PluginMessagePacket("fml:handshake", Unpooled.wrappedBuffer(ForgeHandshakeUtils.generatePluginResetPacket())));
+          connection.setState(StateRegistry.LOGIN);
+        } else {
+          connection.write(new LoginPluginMessagePacket(98,"fml:loginwrapper", Unpooled.wrappedBuffer(ForgeHandshakeUtils.generateResetPacket())));
+        }
+
+        //Prepare to receive reset ACK
+        connection.getChannel().pipeline().addBefore(Connections.MINECRAFT_DECODER,
+                ForgeConstants.RESET_LISTENER, new FML2CRPMResetCompleteDecoder());
+
+        //Transition
+        player.setPhase(WAITING_RESET);
+        WAITING_RESET.onTransitionToNewPhase(player);
+      }
+    },
+    SR {
+      @Override
+      void doReset(ConnectedPlayer player) {
+        ByteBuf buf = Unpooled.buffer();
+        ProtocolUtils.writeVarInt(buf, 0);
+        buf.writeBytes((player.getVirtualHost().get().getHostName() + ":"
+                + player.getVirtualHost().get().getPort()).getBytes(StandardCharsets.UTF_8));
+        player.getConnection().write(new PluginMessagePacket("srvredirect:red", buf));
+
+        Ambassador.getInstance().reconnectSwitchPlayer(player);
+      }
+    };
+
+    void doReset(ConnectedPlayer player) {
+    }
+  }
 }

src/main/java/org/adde0109/ambassador/forge/packet/ACKPacket.java

@@ -0,0 +1,27 @@
+package org.adde0109.ambassador.forge.packet;
+
+import com.velocitypowered.proxy.protocol.ProtocolUtils;
+import io.netty.buffer.ByteBuf;
+import io.netty.buffer.Unpooled;
+
+public class ACKPacket implements IForgeLoginWrapperPacket<Context.ClientContext> {
+
+    private final Context.ClientContext context;
+
+    public ACKPacket(Context.ClientContext context) {
+        this.context = context;
+    }
+    @Override
+    public ByteBuf encode() {
+        ByteBuf buf = Unpooled.buffer();
+
+        ProtocolUtils.writeVarInt(buf, 99);
+
+        return buf;
+    }
+
+    @Override
+    public Context.ClientContext getContext() {
+        return context;
+    }
+}

src/main/java/org/adde0109/ambassador/forge/packet/ConfigDataPacket.java

@@ -0,0 +1,43 @@
+package org.adde0109.ambassador.forge.packet;
+
+import com.velocitypowered.proxy.protocol.ProtocolUtils;
+import io.netty.buffer.ByteBuf;
+import io.netty.buffer.Unpooled;
+
+public class ConfigDataPacket implements IForgeLoginWrapperPacket<Context> {
+
+    private final String fileName;
+    private final byte[] fileData;
+
+    private final Context context;
+
+    public ConfigDataPacket(String fileName, byte[] fileData, Context context) {
+        this.fileName = fileName;
+        this.fileData = fileData;
+        this.context = context;
+    }
+
+    public static ConfigDataPacket read(ByteBuf input, Context context, boolean FML3) {
+        String registryName = ProtocolUtils.readString(input);
+        byte[] snapshot = ProtocolUtils.readByteArray(input);
+
+        return new ConfigDataPacket(registryName, snapshot, context);
+    }
+
+    @Override
+    public ByteBuf encode() {
+        ByteBuf buf = Unpooled.buffer();
+
+        ProtocolUtils.writeVarInt(buf, 4);
+
+        ProtocolUtils.writeString(buf, fileName);
+        ProtocolUtils.writeByteArray(buf, fileData);
+
+        return buf;
+    }
+
+    @Override
+    public Context getContext() {
+        return context;
+    }
+}

src/main/java/org/adde0109/ambassador/forge/packet/Context.java

@@ -0,0 +1,46 @@
+package org.adde0109.ambassador.forge.packet;
+
+public class Context {
+
+  private final int responseID;
+
+  private final String channelName;
+
+  private Context(int responseID, String channelName) {
+    this.responseID = responseID;
+      this.channelName = channelName;
+  }
+
+  public static Context createContext(int responseID, String channelName) {
+    return new Context(responseID, channelName);
+  }
+
+  public static ClientContext createClientContext(int responseID, boolean clientSuccess, String channelName) {
+    return new ClientContext(responseID, clientSuccess, channelName);
+  }
+
+  public static ClientContext fromContext(Context context, boolean clientSuccess) {
+    return new ClientContext(context.responseID, clientSuccess, context.channelName);
+  }
+
+  public int getResponseID() {
+    return responseID;
+  }
+
+  public String getChannelName() {
+    return channelName;
+  }
+
+  public static class ClientContext extends Context {
+
+    private final boolean clientSuccess;
+    ClientContext(int responseID, boolean clientSuccess, String channelName) {
+      super(responseID, channelName);
+      this.clientSuccess = clientSuccess;
+    }
+
+    public boolean success() {
+      return clientSuccess;
+    }
+  }
+}

src/main/java/org/adde0109/ambassador/forge/packet/GenericForgeLoginWrapperPacket.java

@@ -1,31 +1,39 @@
 package org.adde0109.ambassador.forge.packet;
 
-import com.velocitypowered.proxy.protocol.packet.LoginPluginResponse;
-import com.velocitypowered.proxy.protocol.util.DeferredByteBufHolder;
 import io.netty.buffer.ByteBuf;
+import io.netty.buffer.Unpooled;
 
-public class GenericForgeLoginWrapperPacket extends DeferredByteBufHolder implements IForgeLoginWrapperPacket {
-  private final int id;
-  private final boolean success;
+public class GenericForgeLoginWrapperPacket<T extends Context> implements IForgeLoginWrapperPacket<T> {
 
-  public GenericForgeLoginWrapperPacket(ByteBuf input, int id, boolean success) {
-    super(input);
-    this.id = id;
-    this.success = success;
+  private final byte[] content;
+  private final T context;
+
+  public GenericForgeLoginWrapperPacket(byte[] content, T context) {
+    this.content = content;
+    this.context = context;
+  }
+
+
+  static public GenericForgeLoginWrapperPacket<?> read(ByteBuf input, Context context) {
+    byte[] content = new byte[input.readableBytes()];
+    input.readBytes(content);
+    return new GenericForgeLoginWrapperPacket<>(content, context);
   }
 
   @Override
-  public LoginPluginResponse encode() {
-    return new LoginPluginResponse(id, true, content());
+  public ByteBuf encode() {
+    ByteBuf buf = Unpooled.buffer();
+    buf.writeBytes(content);
+    return buf;
+  }
+
+  public byte[] getContent() {
+    return content;
   }
 
   @Override
-  public int getId() {
-    return id;
+  public T getContext() {
+    return context;
   }
 
-  @Override
-  public boolean getSuccess() {
-    return success;
-  }
 }

src/main/java/org/adde0109/ambassador/forge/packet/IForgeLoginWrapperPacket.java

@@ -1,10 +1,8 @@
 package org.adde0109.ambassador.forge.packet;
 
-import com.velocitypowered.proxy.protocol.packet.LoginPluginResponse;
+import io.netty.buffer.ByteBuf;
 
-public interface IForgeLoginWrapperPacket {
-  public LoginPluginResponse encode();
-  public int getId();
-
-  public boolean getSuccess();
+public interface IForgeLoginWrapperPacket<T extends Context> {
+  ByteBuf encode();
+  T getContext();
 }

src/main/java/org/adde0109/ambassador/forge/packet/ModDataPacket.java

@@ -0,0 +1,39 @@
+package org.adde0109.ambassador.forge.packet;
+
+import com.velocitypowered.proxy.protocol.ProtocolUtils;
+import io.netty.buffer.ByteBuf;
+import io.netty.buffer.Unpooled;
+
+public class ModDataPacket implements IForgeLoginWrapperPacket<Context> {
+  private final byte[] content;
+  private final Context context;
+
+  ModDataPacket(byte[] content, Context context) {
+    this.content = content;
+    this.context = context;
+  }
+
+
+  static public ModDataPacket read(ByteBuf input, Context context) {
+    byte[] content = new byte[input.readableBytes()];
+    input.readBytes(content);
+    return new ModDataPacket(content, context);
+  }
+
+  @Override
+  public ByteBuf encode() {
+    ByteBuf buf = Unpooled.buffer();
+    ProtocolUtils.writeVarInt(buf, 5); //PacketID
+    buf.writeBytes(content);
+    return buf;
+  }
+
+  public byte[] getContent() {
+    return content;
+  }
+
+  @Override
+  public Context getContext() {
+    return context;
+  }
+}

src/main/java/org/adde0109/ambassador/forge/packet/ModListPacket.java

@@ -0,0 +1,102 @@
+package org.adde0109.ambassador.forge.packet;
+
+import com.velocitypowered.api.proxy.messages.ChannelIdentifier;
+import com.velocitypowered.api.proxy.messages.MinecraftChannelIdentifier;
+import com.velocitypowered.proxy.protocol.ProtocolUtils;
+import io.netty.buffer.ByteBuf;
+import io.netty.buffer.Unpooled;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+public class ModListPacket implements IForgeLoginWrapperPacket<Context> {
+    private List<String> mods;
+    private Map<ChannelIdentifier, String> channels;
+    private List<String> registries;
+    private final List<String> dataPackRegistries;
+
+    private final Context context;
+    private ModListPacket(List<String> mods, Map<ChannelIdentifier,
+            String> channels, List<String> registries, Context context, List<String> dataPackRegistries) {
+        this.mods = mods;
+        this.channels = channels;
+        this.registries = registries;
+        this.context = context;
+        this.dataPackRegistries = dataPackRegistries;
+    }
+
+    public static ModListPacket read(ByteBuf input, Context context, boolean FML3) {
+
+        List<String> mods = new ArrayList<>();
+        int len = ProtocolUtils.readVarInt(input);
+        for (int x = 0; x < len; x++)
+            mods.add(ProtocolUtils.readString(input, 0x100));
+
+        Map<ChannelIdentifier, String> channels = new HashMap<>();
+        len = ProtocolUtils.readVarInt(input);
+        for (int x = 0; x < len; x++)
+            channels.put(MinecraftChannelIdentifier.from(ProtocolUtils.readString(input, 32767)),
+                    ProtocolUtils.readString(input, 0x100));
+
+        List<String> registries = new ArrayList<>();
+        len = ProtocolUtils.readVarInt(input);
+        for (int x = 0; x < len; x++)
+            registries.add(ProtocolUtils.readString(input, 32767));
+
+        List<String> dataPackRegistries = null;
+        if (FML3 && input.isReadable()) {
+            dataPackRegistries = new ArrayList<>();
+            len = ProtocolUtils.readVarInt(input);
+            for (int x = 0; x < len; x++)
+                dataPackRegistries.add(ProtocolUtils.readString(input, 0x100));
+        }
+
+        return new ModListPacket(mods, channels, registries, context, dataPackRegistries);
+    }
+
+    @Override
+    public ByteBuf encode() {
+        ByteBuf buf = Unpooled.buffer();
+
+        ProtocolUtils.writeVarInt(buf, 1);
+
+        ProtocolUtils.writeVarInt(buf, mods.size());
+        mods.forEach(m -> ProtocolUtils.writeString(buf, m));
+
+        ProtocolUtils.writeVarInt(buf, channels.size());
+        channels.forEach((k, v) -> {
+            ProtocolUtils.writeString(buf,k.getId());
+            ProtocolUtils.writeString(buf,v);
+        });
+
+        ProtocolUtils.writeVarInt(buf, registries.size());
+        registries.forEach(k -> ProtocolUtils.writeString(buf, k));
+
+        if (dataPackRegistries != null) {
+            ProtocolUtils.writeVarInt(buf, dataPackRegistries.size());
+            dataPackRegistries.forEach(k -> ProtocolUtils.writeString(buf, k));
+        }
+
+        return buf;
+    }
+
+    @Override
+    public Context getContext() {
+        return context;
+    }
+
+    public List<String> getMods() {
+        return mods;
+    }
+
+    public Map<ChannelIdentifier, String> getChannels() {
+        return channels;
+    }
+
+    public List<String> getRegistries() {
+        return registries;
+    }
+
+}

src/main/java/org/adde0109/ambassador/forge/packet/ModListReplyPacket.java

@@ -3,7 +3,6 @@ package org.adde0109.ambassador.forge.packet;
 import com.velocitypowered.api.proxy.messages.ChannelIdentifier;
 import com.velocitypowered.api.proxy.messages.MinecraftChannelIdentifier;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
-import com.velocitypowered.proxy.protocol.packet.LoginPluginResponse;
 import io.netty.buffer.ByteBuf;
 import io.netty.buffer.Unpooled;
 
@@ -12,27 +11,22 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 
-public class ModListReplyPacket implements IForgeLoginWrapperPacket {
+public class ModListReplyPacket implements IForgeLoginWrapperPacket<Context.ClientContext> {
 
   private List<String> mods;
   private Map<ChannelIdentifier, String> channels;
   private Map<String, String> registries;
 
-  private final int id;
-
-  private final boolean success;
-
+  private final Context.ClientContext context;
   private ModListReplyPacket(List<String> mods, Map<ChannelIdentifier,
-          String> channels, Map<String, String> registries, int id, boolean success) {
+          String> channels, Map<String, String> registries, Context.ClientContext context) {
     this.mods = mods;
     this.channels = channels;
     this.registries = registries;
-    this.id = id;
-    this.success = success;
+    this.context = context;
   }
 
-  public static ModListReplyPacket read(LoginPluginResponse msg) {
-    ByteBuf input = msg.content();
+  public static ModListReplyPacket read(ByteBuf input, Context.ClientContext context) {
 
     List<String> mods = new ArrayList<>();
     int len = ProtocolUtils.readVarInt(input);
@@ -50,11 +44,11 @@ public class ModListReplyPacket implements IForgeLoginWrapperPacket {
     for (int x = 0; x < len; x++)
       registries.put(ProtocolUtils.readString(input, 32767), ProtocolUtils.readString(input, 0x100));
 
-    return new ModListReplyPacket(mods, channels, registries, msg.getId(), true);
+    return new ModListReplyPacket(mods, channels, registries, context);
   }
 
   @Override
-  public LoginPluginResponse encode() {
+  public ByteBuf encode() {
     ByteBuf buf = Unpooled.buffer();
 
     ProtocolUtils.writeVarInt(buf, 2);
@@ -74,22 +68,12 @@ public class ModListReplyPacket implements IForgeLoginWrapperPacket {
       ProtocolUtils.writeString(buf, v);
     });
 
-    ByteBuf output = Unpooled.buffer();
-    ProtocolUtils.writeString(output, "fml:handshake");
-    ProtocolUtils.writeVarInt(output, buf.readableBytes());
-    output.writeBytes(buf);
-
-    return new LoginPluginResponse(id, true, output);
+    return buf;
   }
 
   @Override
-  public int getId() {
-    return id;
-  }
-
-  @Override
-  public boolean getSuccess() {
-    return success;
+  public Context.ClientContext getContext() {
+    return context;
   }
 
   public List<String> getMods() {

src/main/java/org/adde0109/ambassador/forge/packet/RegistryPacket.java

@@ -0,0 +1,60 @@
+package org.adde0109.ambassador.forge.packet;
+
+import com.velocitypowered.proxy.protocol.ProtocolUtils;
+import io.netty.buffer.ByteBuf;
+import io.netty.buffer.Unpooled;
+
+public class RegistryPacket implements IForgeLoginWrapperPacket<Context> {
+
+  private final String registryName;
+
+  private final byte[] snapshot;
+
+  private final Context context;
+  public RegistryPacket(String registryName, byte[] snapshot, Context context) {
+    this.registryName = registryName;
+    this.snapshot = snapshot;
+    this.context = context;
+  }
+
+  public static RegistryPacket read(ByteBuf input, Context context, boolean FML3) {
+    String registryName = ProtocolUtils.readString(input);
+    byte[] snapshot = null;
+    if (input.readBoolean()) {
+      snapshot = new byte[input.readableBytes()];
+      input.readBytes(snapshot);
+    }
+
+    return new RegistryPacket(registryName, snapshot, context);
+  }
+
+  @Override
+  public ByteBuf encode() {
+    ByteBuf buf = Unpooled.buffer();
+
+    ProtocolUtils.writeVarInt(buf, 3);
+
+    ProtocolUtils.writeString(buf, registryName);
+    if (snapshot != null) {
+      buf.writeBoolean(true);
+      buf.writeBytes(snapshot);
+    } else {
+      buf.writeBoolean(false);
+    }
+
+    return buf;
+  }
+
+  @Override
+  public Context getContext() {
+    return context;
+  }
+
+  public String getRegistryName() {
+    return registryName;
+  }
+
+  public byte[] getSnapshot() {
+    return snapshot;
+  }
+}

src/main/java/org/adde0109/ambassador/forge/pipeline/CommandDecoderErrorCatcher.java

@@ -8,7 +8,7 @@ import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
 import com.velocitypowered.proxy.protocol.StateRegistry;
 import com.velocitypowered.proxy.protocol.netty.MinecraftDecoder;
-import com.velocitypowered.proxy.protocol.packet.AvailableCommands;
+import com.velocitypowered.proxy.protocol.packet.AvailableCommandsPacket;
 import com.velocitypowered.proxy.util.except.QuietRuntimeException;
 import io.netty.buffer.ByteBuf;
 import io.netty.channel.ChannelHandlerContext;
@@ -43,7 +43,7 @@ public class CommandDecoderErrorCatcher extends ChannelInboundHandlerAdapter {
       int packetId = ProtocolUtils.readVarInt(buf);
       MinecraftPacket packet = registry.createPacket(packetId);
       buf.readerIndex(originalReaderIndex);
-      if (packet instanceof AvailableCommands) {
+      if (packet instanceof AvailableCommandsPacket) {
         try {
           ((MinecraftDecoder) ctx.pipeline().get(Connections.MINECRAFT_DECODER)).channelRead(ctx, msg);
         } catch (QuietRuntimeException | CorruptedFrameException e) {

src/main/java/org/adde0109/ambassador/forge/pipeline/ForgeLoginWrapperCodec.java

@@ -0,0 +1,146 @@
+package org.adde0109.ambassador.forge.pipeline;
+
+import com.velocitypowered.proxy.protocol.ProtocolUtils;
+import com.velocitypowered.proxy.protocol.packet.LoginPluginMessagePacket;
+import com.velocitypowered.proxy.protocol.packet.LoginPluginResponsePacket;
+import com.velocitypowered.proxy.protocol.util.DeferredByteBufHolder;
+import io.netty.buffer.ByteBuf;
+import io.netty.buffer.Unpooled;
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.handler.codec.DecoderException;
+import io.netty.handler.codec.MessageToMessageCodec;
+import io.netty.util.ReferenceCountUtil;
+import org.adde0109.ambassador.Ambassador;
+import org.adde0109.ambassador.forge.packet.*;
+
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+public class ForgeLoginWrapperCodec extends MessageToMessageCodec<DeferredByteBufHolder, IForgeLoginWrapperPacket<?>> {
+
+  private final boolean FML3;
+  private final Map<Integer, Context> loginWrapperContexts = new HashMap<>();
+
+  public ForgeLoginWrapperCodec(boolean fml3) {
+    FML3 = fml3;
+  }
+
+  @Override
+  public boolean acceptInboundMessage(Object msg) throws Exception {
+    return (msg instanceof LoginPluginMessagePacket
+            && ((LoginPluginMessagePacket) msg).getChannel().equals("fml:loginwrapper"))
+            || (msg instanceof LoginPluginResponsePacket
+            && loginWrapperContexts.containsKey(((LoginPluginResponsePacket) msg).getId()));
+  }
+
+  @Override
+  protected void decode(ChannelHandlerContext ctx, DeferredByteBufHolder in, List<Object> out) throws Exception {
+
+    ByteBuf buf = in.content();
+
+    Context context;
+    if (in instanceof LoginPluginResponsePacket msg) {
+      //Continue from stored context
+      context = Context.fromContext(
+              loginWrapperContexts.remove(((LoginPluginResponsePacket) msg).getId()), msg.isSuccess());
+      if (!msg.isSuccess()) {
+        //Nothing to read, just create an empty packet.
+        out.add(GenericForgeLoginWrapperPacket.read(buf, context));
+        return;
+      } else {
+        String channel = ProtocolUtils.readString(buf); //Read the channel even though we know the channel by context.
+        Ambassador.getInstance();
+      }
+    } else {
+      //New context.
+      LoginPluginMessagePacket msg = (LoginPluginMessagePacket) in;
+      String channel = ProtocolUtils.readString(buf);
+
+      context = Context.createContext(msg.getId(), channel);
+    }
+
+    //Decoding of data starts here - channel already read
+    int originalReaderIndex = buf.readerIndex();
+
+    if (!context.getChannelName().equals("fml:handshake")) {
+      out.add(GenericForgeLoginWrapperPacket.read(buf, context));
+    } else {
+      int length = ProtocolUtils.readVarInt(buf);
+      int packetID = ProtocolUtils.readVarInt(buf);
+      if (context instanceof Context.ClientContext clientContext) {
+        switch (packetID) {
+          case 2:
+            out.add(ModListReplyPacket.read(buf, clientContext));
+            break;
+          case 99:
+            out.add(new ACKPacket(clientContext));
+            break;
+          default:
+            //Undo decoding
+            buf.readerIndex(originalReaderIndex);
+            out.add(GenericForgeLoginWrapperPacket.read(buf, context));
+            if (Ambassador.getInstance().config.isDebugMode()) {
+              Ambassador.getInstance().logger.warn(
+                      "Unrecognised packet id received from client on fml:handshake: " + packetID);
+            }
+        }
+      } else {
+        switch (packetID) {
+          case 1:
+            out.add(ModListPacket.read(buf, context, FML3));
+            break;
+          case 3:
+            out.add(RegistryPacket.read(buf, context, FML3));
+            break;
+          case 4:
+            out.add(ConfigDataPacket.read(buf, context, FML3));
+            break;
+          case 5:
+            if (FML3) {
+              out.add(ModDataPacket.read(buf, context));
+              break;
+            }
+          default:
+            //Undo decoding
+            buf.readerIndex(originalReaderIndex);
+            out.add(GenericForgeLoginWrapperPacket.read(buf, context));
+            if (Ambassador.getInstance().config.isDebugMode()) {
+              Ambassador.getInstance().logger.warn(
+                      "Unrecognised packet id received from server on fml:handshake: " + packetID);
+            }
+        }
+      }
+    }
+  }
+
+  @Override
+  protected void encode(ChannelHandlerContext ctx, IForgeLoginWrapperPacket<?> msg, List<Object> out) throws Exception {
+    ByteBuf wrapped;
+
+    boolean data = !(msg.getContext() instanceof Context.ClientContext clientContext && !clientContext.success());
+
+    boolean includeLength = !(msg instanceof GenericForgeLoginWrapperPacket);
+
+    String channel = msg.getContext().getChannelName();
+
+    wrapped = Unpooled.buffer();
+
+    if (data) {
+      ByteBuf encoded = msg.encode();
+      ProtocolUtils.writeString(wrapped, channel);
+      if (includeLength)
+        ProtocolUtils.writeVarInt(wrapped, encoded.readableBytes());
+      wrapped.writeBytes(encoded);
+      encoded.release();
+    }
+    if (msg.getContext() instanceof Context.ClientContext clientContext) {
+      out.add(new LoginPluginResponsePacket(clientContext.getResponseID(), clientContext.success(), wrapped));
+    } else {
+      out.add(new LoginPluginMessagePacket(msg.getContext().getResponseID(), "fml:loginwrapper", wrapped));
+      if (!(msg instanceof ModDataPacket)) {  //ModDataPacket doesn't require a response
+        this.loginWrapperContexts.put(msg.getContext().getResponseID(), msg.getContext());
+      }
+    }
+  }
+}

src/main/java/org/adde0109/ambassador/forge/pipeline/ForgeLoginWrapperDecoder.java

@@ -1,45 +0,0 @@
-package org.adde0109.ambassador.forge.pipeline;
-
-import com.velocitypowered.proxy.protocol.ProtocolUtils;
-import com.velocitypowered.proxy.protocol.packet.LoginPluginResponse;
-import io.netty.buffer.ByteBuf;
-import io.netty.channel.ChannelHandlerContext;
-import io.netty.handler.codec.MessageToMessageDecoder;
-import org.adde0109.ambassador.forge.packet.GenericForgeLoginWrapperPacket;
-import org.adde0109.ambassador.forge.packet.ModListReplyPacket;
-
-import java.util.ArrayList;
-import java.util.List;
-
-public class ForgeLoginWrapperDecoder extends MessageToMessageDecoder<LoginPluginResponse> {
-
-  private final List<Integer> loginWrapperIDs = new ArrayList<>();
-
-  @Override
-  protected void decode(ChannelHandlerContext ctx, LoginPluginResponse msg, List<Object> out) throws Exception {
-    ByteBuf buf = msg.content();
-    if (!loginWrapperIDs.remove((Integer) msg.getId())) {
-      out.add(msg.retain());
-      return;
-    }
-    int originalReaderIndex = msg.content().readerIndex();
-    String channel = ProtocolUtils.readString(buf);
-    if (!channel.equals("fml:handshake")) {
-      buf.readerIndex(originalReaderIndex);
-      out.add(new GenericForgeLoginWrapperPacket(buf.retain(), msg.getId(), true));
-      return;
-    }
-    int length = ProtocolUtils.readVarInt(buf);
-    int packetID = ProtocolUtils.readVarInt(buf);
-    if (packetID == 2) {
-      out.add(ModListReplyPacket.read(msg));
-    } else {
-      buf.readerIndex(originalReaderIndex);
-      out.add(new GenericForgeLoginWrapperPacket(buf.retain(), msg.getId(), true));
-    }
-  }
-
-  public void registerLoginWrapperID(int loginWrapperID) {
-    this.loginWrapperIDs.add(loginWrapperID);
-  }
-}

src/main/java/org/adde0109/ambassador/forge/pipeline/ForgeLoginWrapperHandler.java

@@ -1,25 +1,42 @@
 package org.adde0109.ambassador.forge.pipeline;
 
+import com.velocitypowered.proxy.connection.MinecraftConnectionAssociation;
+import com.velocitypowered.proxy.connection.backend.VelocityServerConnection;
 import com.velocitypowered.proxy.connection.client.ConnectedPlayer;
 import io.netty.channel.ChannelHandlerContext;
 import io.netty.channel.SimpleChannelInboundHandler;
 import io.netty.util.ReferenceCountUtil;
+import org.adde0109.ambassador.forge.ForgeConstants;
+import org.adde0109.ambassador.forge.ForgeFMLConnectionType;
+import org.adde0109.ambassador.forge.VelocityForgeBackendConnectionPhase;
+import org.adde0109.ambassador.forge.packet.Context;
 import org.adde0109.ambassador.forge.packet.IForgeLoginWrapperPacket;
 import org.adde0109.ambassador.forge.VelocityForgeClientConnectionPhase;
 
-public class ForgeLoginWrapperHandler extends SimpleChannelInboundHandler<IForgeLoginWrapperPacket> {
+public class ForgeLoginWrapperHandler extends SimpleChannelInboundHandler<IForgeLoginWrapperPacket<?>> {
 
-  private final ConnectedPlayer player;
+  private final MinecraftConnectionAssociation connection;
 
 
-  public ForgeLoginWrapperHandler(ConnectedPlayer player) {
+  public ForgeLoginWrapperHandler(MinecraftConnectionAssociation connection) {
     super(false);
-    this.player = player;
+    this.connection = connection;
   }
 
   @Override
   protected void channelRead0(ChannelHandlerContext ctx, IForgeLoginWrapperPacket msg) throws Exception {
+    if (connection instanceof ConnectedPlayer player) {
       VelocityForgeClientConnectionPhase phase = (VelocityForgeClientConnectionPhase) player.getPhase();
       phase.handle(player,msg,player.getConnectionInFlight());
+    } else if (connection instanceof VelocityServerConnection serverConnection){
+      if (!(serverConnection.getConnection().getType() instanceof ForgeFMLConnectionType)) {
+        serverConnection.getConnection().setType(serverConnection.getPlayer().getConnection().getType());
+        serverConnection.setConnectionPhase(serverConnection.getConnection().getType().getInitialBackendPhase());
+      }
+
+      VelocityForgeBackendConnectionPhase phase =
+              (VelocityForgeBackendConnectionPhase) serverConnection.getPhase();
+      phase.handle(serverConnection, serverConnection.getPlayer(), msg);
+    }
   }
 }

src/main/java/org/adde0109/ambassador/velocity/VelocityEventHandler.java

@@ -3,7 +3,6 @@ package org.adde0109.ambassador.velocity;
 import com.velocitypowered.api.event.Continuation;
 import com.velocitypowered.api.event.PostOrder;
 import com.velocitypowered.api.event.Subscribe;
-import com.velocitypowered.api.event.connection.LoginEvent;
 import com.velocitypowered.api.event.connection.PostLoginEvent;
 import com.velocitypowered.api.event.player.*;
 import com.velocitypowered.api.proxy.server.RegisteredServer;
@@ -12,12 +11,11 @@ import com.velocitypowered.proxy.VelocityServer;
 import com.velocitypowered.proxy.connection.client.ConnectedPlayer;
 import com.velocitypowered.proxy.network.Connections;
 import com.velocitypowered.proxy.protocol.StateRegistry;
-import net.kyori.adventure.text.Component;
 import org.adde0109.ambassador.Ambassador;
 import org.adde0109.ambassador.forge.ForgeConstants;
 import org.adde0109.ambassador.forge.ForgeFMLConnectionType;
 import org.adde0109.ambassador.forge.VelocityForgeClientConnectionPhase;
-import org.adde0109.ambassador.forge.pipeline.ForgeLoginWrapperDecoder;
+import org.adde0109.ambassador.forge.pipeline.ForgeLoginWrapperCodec;
 import org.adde0109.ambassador.forge.pipeline.ForgeLoginWrapperHandler;
 
 public class VelocityEventHandler {
@@ -39,7 +37,8 @@ public class VelocityEventHandler {
 
         player.getConnection().getChannel().pipeline().addBefore(
                 Connections.HANDLER,
-                ForgeConstants.FORGE_HANDSHAKE_DECODER, new ForgeLoginWrapperDecoder());
+                ForgeConstants.FORGE_HANDSHAKE_DECODER, new ForgeLoginWrapperCodec(
+                        player.getConnection().getType() == ForgeConstants.ForgeFML3));
         player.getConnection().getChannel().pipeline().addAfter(
                 ForgeConstants.FORGE_HANDSHAKE_DECODER,
                 ForgeConstants.FORGE_HANDSHAKE_HANDLER, new ForgeLoginWrapperHandler(player));
@@ -72,6 +71,12 @@ public class VelocityEventHandler {
     player.setModInfo(new ModInfo("Channels", event.getChannels().stream().map((id) -> {
       return new ModInfo.Mod(id.getId(), "");
     }).toList()));
+
+    VelocityForgeClientConnectionPhase clientPhase = (VelocityForgeClientConnectionPhase) player.getPhase();
+    //If reset typ is still unknown, set it!
+    if (clientPhase.getResetType() == VelocityForgeClientConnectionPhase.ClientResetType.UNKNOWN) {
+      clientPhase.updateResetType(player);
+    }
   }
 
 }

src/main/java/org/adde0109/ambassador/velocity/backend/FMLMarkerAdder.java

@@ -6,7 +6,7 @@ import com.velocitypowered.proxy.connection.ConnectionTypes;
 import com.velocitypowered.proxy.connection.MinecraftConnection;
 import com.velocitypowered.proxy.connection.backend.VelocityServerConnection;
 import com.velocitypowered.proxy.network.Connections;
-import com.velocitypowered.proxy.protocol.packet.Handshake;
+import com.velocitypowered.proxy.protocol.packet.HandshakePacket;
 import io.netty.channel.*;
 import io.netty.handler.codec.MessageToMessageEncoder;
 import org.adde0109.ambassador.forge.ForgeConstants;
@@ -16,17 +16,17 @@ import java.util.List;
 
 import static com.velocitypowered.proxy.connection.forge.legacy.LegacyForgeConstants.HANDSHAKE_HOSTNAME_TOKEN;
 
-public class FMLMarkerAdder extends MessageToMessageEncoder<Handshake> {
+public class FMLMarkerAdder extends MessageToMessageEncoder<HandshakePacket> {
 
   final VelocityServer server;
 
   public FMLMarkerAdder(VelocityServer server) {
-    super(Handshake.class);
+    super(HandshakePacket.class);
     this.server = server;
   }
 
   @Override
-  protected void encode(ChannelHandlerContext ctx, Handshake msg, List<Object> out) {
+  protected void encode(ChannelHandlerContext ctx, HandshakePacket msg, List<Object> out) {
     MinecraftConnection connection = (MinecraftConnection) ctx.pipeline().get(Connections.HANDLER);
     VelocityServerConnection serverConnection = (VelocityServerConnection) connection.getAssociation();
     PlayerInfoForwarding forwardingMode = server.getConfiguration().getPlayerInfoForwardingMode();

src/main/java/org/adde0109/ambassador/velocity/backend/ForgeLoginSessionHandler.java

@@ -6,9 +6,9 @@ import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.connection.backend.*;
 import com.velocitypowered.proxy.connection.client.ConnectedPlayer;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
-import com.velocitypowered.proxy.protocol.packet.Disconnect;
-import com.velocitypowered.proxy.protocol.packet.LoginPluginMessage;
-import com.velocitypowered.proxy.protocol.packet.ServerLoginSuccess;
+import com.velocitypowered.proxy.protocol.packet.DisconnectPacket;
+import com.velocitypowered.proxy.protocol.packet.LoginPluginMessagePacket;
+import com.velocitypowered.proxy.protocol.packet.ServerLoginSuccessPacket;
 import com.velocitypowered.proxy.util.except.QuietRuntimeException;
 import io.netty.buffer.Unpooled;
 import org.adde0109.ambassador.forge.*;
@@ -26,71 +26,33 @@ public class ForgeLoginSessionHandler implements MinecraftSessionHandler {
   }
 
   @Override
-  public boolean handle(LoginPluginMessage packet) {
-    if (packet.getChannel().equals("fml:loginwrapper")) {
-      if (serverConnection.getPhase() == BackendConnectionPhases.UNKNOWN) {
-        VelocityForgeBackendConnectionPhase.NOT_STARTED.handle(serverConnection,serverConnection.getPlayer(),packet);
-      } else if (serverConnection.getPhase() instanceof VelocityForgeBackendConnectionPhase phase1) {
-        phase1.handle(serverConnection,serverConnection.getPlayer(),packet);
-      }
-      return true;
-    }
-    return original.handle(packet);
-  }
-
-  @Override
-  public boolean handle(ServerLoginSuccess packet) {
+  public boolean handle(ServerLoginSuccessPacket packet) {
     if ((serverConnection.getPhase() instanceof VelocityForgeBackendConnectionPhase phase)) {
       phase.onLoginSuccess(serverConnection,serverConnection.getPlayer());
     }
-    original.handle(packet);
-    if (serverConnection.getConnection() == null) {
-      return true;
-    }
+
+    original.handle(packet);  //Can lead to disconnect.
+
+    //If we are still connected after handling that package.
+    if (serverConnection.getConnection() != null) {
       ConnectedPlayer player = serverConnection.getPlayer();
-    if (!(serverConnection.getConnection().getType() instanceof ForgeFMLConnectionType)) {
-      if (player.getConnectedServer() == null ||
-              player.getConnectedServer().getConnection().getType() instanceof ForgeFMLConnectionType) {
-        //Initial Vanilla
-        //Forge -> vanilla
-        player.getPhase().resetConnectionPhase(player);
-        player.getConnectionInFlight().getConnection().getChannel().config().setAutoRead(false);
-      }
-    } else {
-      ((VelocityForgeClientConnectionPhase) player.getPhase()).complete(player);
+
+      VelocityForgeClientConnectionPhase clientPhase = (VelocityForgeClientConnectionPhase) player.getPhase();
+      clientPhase.complete(player);
     }
+
     return true;
   }
 
 
 
   @Override
-  public boolean handle(Disconnect packet) {
-    if (!serverConnection.getPlayer().getPhase().consideredComplete()) {
-      serverConnection.getPlayer().handleConnectionException(serverConnection.getServer(), packet, false);
-      return true;
-    }
+  public boolean handle(DisconnectPacket packet) {
     return original.handle(packet);
   }
 
   @Override
   public void disconnected() {
-    //Same as default just not safe.
-    if (!serverConnection.getPlayer().getPhase().consideredComplete()) {
-      if (server.getConfiguration().getPlayerInfoForwardingMode() == PlayerInfoForwarding.LEGACY) {
-        serverConnection.getPlayer().handleConnectionException(serverConnection.getServer(),
-                new QuietRuntimeException("The connection to the remote server was unexpectedly closed.\n"
-                        + "This is usually because the remote server does not have BungeeCord IP forwarding "
-                        + "correctly enabled.\nSee https://velocitypowered.com/wiki/users/forwarding/ "
-                        + "for instructions on how to configure player info forwarding correctly."),
-        false);
-      } else {
-        serverConnection.getPlayer().handleConnectionException(serverConnection.getServer(),
-                new QuietRuntimeException("The connection to the remote server was unexpectedly closed."),
-        false);
-      }
-      return;
-    }
       original.disconnected();
   }
 

src/main/java/org/adde0109/ambassador/velocity/backend/ForgePlaySessionHandler.java

@@ -1,41 +0,0 @@
-package org.adde0109.ambassador.velocity.backend;
-
-import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
-import com.velocitypowered.proxy.connection.backend.TransitionSessionHandler;
-import com.velocitypowered.proxy.connection.backend.VelocityServerConnection;
-import com.velocitypowered.proxy.protocol.MinecraftPacket;
-import com.velocitypowered.proxy.protocol.packet.JoinGame;
-import org.adde0109.ambassador.forge.VelocityForgeClientConnectionPhase;
-
-public class ForgePlaySessionHandler implements MinecraftSessionHandler {
-
-  private final TransitionSessionHandler original;
-  private final VelocityServerConnection serverConnection;
-
-  public ForgePlaySessionHandler(TransitionSessionHandler original, VelocityServerConnection serverConnection) {
-    this.original = original;
-    this.serverConnection = serverConnection;
-  }
-
-  @Override
-  public boolean handle(JoinGame packet) {
-    if (serverConnection.getPlayer().getPhase() instanceof VelocityForgeClientConnectionPhase clientPhase) {
-      serverConnection.getPlayer().setPhase(VelocityForgeClientConnectionPhase.RESETTABLE);
-    }
-    return MinecraftSessionHandler.super.handle(packet);
-  }
-
-  @Override
-  public void disconnected() {
-    original.disconnected();
-  }
-
-  public void handleGeneric(MinecraftPacket packet) {
-    if (!packet.handle(original))
-      original.handleGeneric(packet);
-  }
-
-  public MinecraftSessionHandler getOriginal() {
-    return this.original;
-  }
-}

src/main/java/org/adde0109/ambassador/velocity/backend/VelocityForgeBackendHandshakeHandler.java

@@ -4,10 +4,14 @@ import com.velocitypowered.proxy.VelocityServer;
 import com.velocitypowered.proxy.connection.MinecraftConnection;
 import com.velocitypowered.proxy.connection.backend.LoginSessionHandler;
 import com.velocitypowered.proxy.connection.backend.VelocityServerConnection;
+import com.velocitypowered.proxy.connection.client.ConnectedPlayer;
 import com.velocitypowered.proxy.network.Connections;
 import com.velocitypowered.proxy.protocol.StateRegistry;
 import io.netty.channel.*;
+import org.adde0109.ambassador.forge.ForgeConstants;
 import org.adde0109.ambassador.forge.ForgeFMLConnectionType;
+import org.adde0109.ambassador.forge.pipeline.ForgeLoginWrapperCodec;
+import org.adde0109.ambassador.forge.pipeline.ForgeLoginWrapperHandler;
 import org.jetbrains.annotations.NotNull;
 
 public class VelocityForgeBackendHandshakeHandler extends ChannelInboundHandlerAdapter {
@@ -25,9 +29,18 @@ public class VelocityForgeBackendHandshakeHandler extends ChannelInboundHandlerA
 
     ctx.pipeline().remove(this);
 
-    if (serverConnection.getPlayer().getConnection().getType() instanceof ForgeFMLConnectionType) {
+    ConnectedPlayer player = serverConnection.getPlayer();
+    if (player.getConnection().getType() instanceof ForgeFMLConnectionType) {
       ForgeLoginSessionHandler forgeLoginSessionHandler = new ForgeLoginSessionHandler((LoginSessionHandler) connection.getActiveSessionHandler(), serverConnection,server);
       connection.setActiveSessionHandler(StateRegistry.LOGIN, forgeLoginSessionHandler);
+
+      serverConnection.getConnection().getChannel().pipeline().addBefore(
+              Connections.HANDLER,
+              ForgeConstants.FORGE_HANDSHAKE_DECODER, new ForgeLoginWrapperCodec(
+                      player.getConnection().getType() == ForgeConstants.ForgeFML3));
+      serverConnection.getConnection().getChannel().pipeline().addAfter(
+              ForgeConstants.FORGE_HANDSHAKE_DECODER,
+              ForgeConstants.FORGE_HANDSHAKE_HANDLER, new ForgeLoginWrapperHandler(serverConnection));
     }
 
     ctx.pipeline().fireChannelActive();

src/main/java/org/adde0109/ambassador/velocity/client/FML2CRPMResetCompleteDecoder.java

@@ -5,6 +5,7 @@ import io.netty.buffer.ByteBuf;
 import io.netty.buffer.Unpooled;
 import io.netty.channel.ChannelHandlerContext;
 import io.netty.channel.ChannelInboundHandlerAdapter;
+import org.adde0109.ambassador.forge.packet.Context;
 import org.adde0109.ambassador.forge.packet.GenericForgeLoginWrapperPacket;
 import org.adde0109.ambassador.forge.packet.IForgeLoginWrapperPacket;
 
@@ -26,8 +27,8 @@ public class FML2CRPMResetCompleteDecoder extends ChannelInboundHandlerAdapter {
           boolean success = buf.readBoolean();
           if (id == 98) {
             try {
-              IForgeLoginWrapperPacket packet = new GenericForgeLoginWrapperPacket(Unpooled.EMPTY_BUFFER, id, success);
-              ctx.fireChannelRead(packet);
+              ctx.fireChannelRead(GenericForgeLoginWrapperPacket.read(
+                      Unpooled.EMPTY_BUFFER, Context.createClientContext(id, success, "fml:handshake")));
             } finally {
               buf.release();
             }

src/main/java/org/adde0109/ambassador/velocity/client/OutboundSuccessHolder.java

@@ -1,13 +1,13 @@
 package org.adde0109.ambassador.velocity.client;
 
-import com.velocitypowered.proxy.protocol.packet.ServerLoginSuccess;
+import com.velocitypowered.proxy.protocol.packet.ServerLoginSuccessPacket;
 import io.netty.channel.ChannelHandlerContext;
 import io.netty.channel.ChannelOutboundHandlerAdapter;
 import io.netty.channel.ChannelPromise;
 
 public class OutboundSuccessHolder extends ChannelOutboundHandlerAdapter {
 
-  private ServerLoginSuccess packet;
+  private ServerLoginSuccessPacket packet;
   private ChannelHandlerContext ctx;
 
   @Override
@@ -17,7 +17,7 @@ public class OutboundSuccessHolder extends ChannelOutboundHandlerAdapter {
 
   @Override
   public void write(ChannelHandlerContext ctx, Object msg, ChannelPromise promise) throws Exception {
-    if ((msg instanceof ServerLoginSuccess packet)) {
+    if ((msg instanceof ServerLoginSuccessPacket packet)) {
       this.packet = packet;
     } else {
       ctx.write(msg, promise);

src/main/java/org/adde0109/ambassador/velocity/client/VelocityHandshakeSessionHandler.java

@@ -7,7 +7,7 @@ import com.velocitypowered.proxy.connection.client.HandshakeSessionHandler;
 import com.velocitypowered.proxy.network.Connections;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.StateRegistry;
-import com.velocitypowered.proxy.protocol.packet.Handshake;
+import com.velocitypowered.proxy.protocol.packet.HandshakePacket;
 import io.netty.buffer.ByteBuf;
 import org.adde0109.ambassador.forge.ForgeConstants;
 
@@ -22,23 +22,21 @@ public class VelocityHandshakeSessionHandler extends HandshakeSessionHandler  {
   }
 
   @Override
-  public boolean handle(Handshake handshake) {
+  public boolean handle(HandshakePacket handshake) {
     handshake.handle(original);
     if (connection.getType() == ConnectionTypes.VANILLA) {
       final String[] markerSplit = handshake.getServerAddress().split("\0");
-      if (connection.getState() == StateRegistry.LOGIN && markerSplit.length > 1) {
+      if (connection.getState() == StateRegistry.LOGIN && markerSplit.length > 1 && markerSplit[1].startsWith("FML")) {
         switch (markerSplit[1]) {
           case "FML2":
             connection.setType(ForgeConstants.ForgeFML2);
-            connection.getChannel().pipeline().addAfter(Connections.MINECRAFT_ENCODER,ForgeConstants.SERVER_SUCCESS_LISTENER, new OutboundSuccessHolder());
-            connection.getChannel().pipeline().addAfter(Connections.MINECRAFT_ENCODER,ForgeConstants.PLUGIN_PACKET_QUEUE, new ClientPacketQueue(StateRegistry.LOGIN));
             break;
           case "FML3":
             connection.setType(ForgeConstants.ForgeFML3);
-            connection.getChannel().pipeline().addAfter(Connections.MINECRAFT_ENCODER,ForgeConstants.SERVER_SUCCESS_LISTENER, new OutboundSuccessHolder());
-            connection.getChannel().pipeline().addAfter(Connections.MINECRAFT_ENCODER,ForgeConstants.PLUGIN_PACKET_QUEUE, new ClientPacketQueue(StateRegistry.LOGIN));
             break;
         }
+        connection.getChannel().pipeline().addAfter(Connections.MINECRAFT_ENCODER,ForgeConstants.SERVER_SUCCESS_LISTENER, new OutboundSuccessHolder());
+        connection.getChannel().pipeline().addAfter(Connections.MINECRAFT_ENCODER,ForgeConstants.PLUGIN_PACKET_QUEUE, new ClientPacketQueue(StateRegistry.LOGIN));
       }
     }
     return true;

src/main/resources/default-ambassador.toml

@@ -1,9 +1,29 @@
 # Do not change this
-config-version = "1.1"
+config-version = "2.1"
 
-# Message displayed to the player when disconnected from proxy during server switch.
-# Legacy color codes and JSON are accepted.
-disconnect-reset-message = "&6Please reconnect"
 # How much time the player has to reconnect before canceling the server switch. (In seconds)
-server-switch-cancellation-time = 120
+# Only for players with ServerRedirect mod installed. Set to -1 to disable ServerRedirect mod support.
+serverRedirectTimeout = 30
+
+# Silence PCF absence warnings.
 silence-warnings = false
+
+# Allow server switches without reset even though the new server's registries don't match the old server’s registry.
+# Large modpacks often needs this set to true. Warning: This is a safety measure and setting this to true
+# can lead to unstable behaviour.
+bypass-registry-checks = false
+
+# Allow player to switch without reset when the server's mods don't match. Even more unstable than bypassRegistryCheck.
+# Warning: This is a safety measure for when bypassRegistryCheck is true. Setting this to also true can cause crashes.
+bypass-mod-checks = false
+
+# Only for debug/troubleshooting
+debug-mode = false
+
+# Make the player reconnect when server switching as a last resort if
+# the player can't reset or switch servers without resetting.
+enable-kick-reset = false
+
+# Message to display when player gets kicked due to server switching according to enable-kick-reset.
+# This input is deserialzied as MiniMessage and support formating according to the MiniMessage format.
+reconnect-message = "<red>Please reconnect.</red>"