feat: Add extra vHost data in ConnectionHandshakeEvent

api/src/main/java/com/velocitypowered/api/event/connection/ConnectionHandshakeEvent.java

@@ -20,10 +20,19 @@ public final class ConnectionHandshakeEvent {
 
   private final InboundConnection connection;
   private final HandshakeIntent intent;
+  private final String extraDataInHandshake;
 
-  public ConnectionHandshakeEvent(InboundConnection connection, HandshakeIntent intent) {
+  /**
+   * Creates a new event.
+   *
+   * @param connection the inbound connection
+   * @param intent the intent of the handshake
+   * @param extraDataInHandshake the extra data in the handshake
+   */
+  public ConnectionHandshakeEvent(InboundConnection connection, HandshakeIntent intent, String extraDataInHandshake) {
     this.connection = Preconditions.checkNotNull(connection, "connection");
     this.intent = Preconditions.checkNotNull(intent, "intent");
+    this.extraDataInHandshake = Preconditions.checkNotNull(extraDataInHandshake, "extraDataInHandshake");
   }
 
   /**
@@ -31,12 +40,13 @@ public final class ConnectionHandshakeEvent {
    * that have not yet updated their integration tests.
    *
    * @param connection the inbound connection
-   * @deprecated use {@link #ConnectionHandshakeEvent(InboundConnection, HandshakeIntent)}
+   * @deprecated use {@link #ConnectionHandshakeEvent(InboundConnection, HandshakeIntent, String)}
    */
   @Deprecated(forRemoval = true)
   public ConnectionHandshakeEvent(InboundConnection connection) {
     this.connection = Preconditions.checkNotNull(connection, "connection");
     this.intent = HandshakeIntent.LOGIN;
+    this.extraDataInHandshake = "";
   }
 
   public InboundConnection getConnection() {
@@ -47,6 +57,10 @@ public final class ConnectionHandshakeEvent {
     return this.intent;
   }
 
+  public String getExtraDataInHandshake() {
+    return this.extraDataInHandshake;
+  }
+
   @Override
   public String toString() {
     return "ConnectionHandshakeEvent{"

proxy/src/main/java/com/velocitypowered/proxy/connection/client/HandshakeSessionHandler.java

@@ -105,7 +105,7 @@ public class HandshakeSessionHandler implements MinecraftSessionHandler {
       switch (nextState) {
         case STATUS -> connection.setActiveSessionHandler(StateRegistry.STATUS,
                 new StatusSessionHandler(server, ic));
-        case LOGIN -> this.handleLogin(handshake, ic);
+        case LOGIN -> this.handleLogin(handshake, ic, getExtraVhostData(handshake.getServerAddress()));
         default ->
           // If you get this, it's a bug in Velocity.
           throw new AssertionError("getStateForProtocol provided invalid state!");
@@ -123,7 +123,7 @@ public class HandshakeSessionHandler implements MinecraftSessionHandler {
     };
   }
 
-  private void handleLogin(HandshakePacket handshake, InitialInboundConnection ic) {
+  private void handleLogin(HandshakePacket handshake, InitialInboundConnection ic, String extraData) {
     if (!handshake.getProtocolVersion().isSupported()) {
       // Bump connection into correct protocol state so that we can send the disconnect packet.
       connection.setState(StateRegistry.LOGIN);
@@ -157,7 +157,7 @@ public class HandshakeSessionHandler implements MinecraftSessionHandler {
 
     final LoginInboundConnection lic = new LoginInboundConnection(ic);
     server.getEventManager().fireAndForget(
-            new ConnectionHandshakeEvent(lic, handshake.getIntent()));
+            new ConnectionHandshakeEvent(lic, handshake.getIntent(), extraData));
     connection.setActiveSessionHandler(StateRegistry.LOGIN,
             new InitialLoginSessionHandler(server, connection, lic));
   }
@@ -206,6 +206,23 @@ public class HandshakeSessionHandler implements MinecraftSessionHandler {
     return cleaned;
   }
 
+  /**
+   * Extracts the extra data from the specified hostname.
+   *
+   * @param hostname the host name to extract the extra data from
+   * @return the extra data
+   */
+  @VisibleForTesting
+  static String getExtraVhostData(String hostname) {
+    // Add extra data support
+    String data = "";
+    if (hostname.contains("\0")) {
+      String[] split = hostname.split("\0", 2);
+      data = "\0" + split[1];
+    }
+    return data;
+  }
+
   @Override
   public void handleGeneric(MinecraftPacket packet) {
     // Unknown packet received. Better to close the connection.