Added an option to require linked accounts

common/src/main/java/org/geysermc/floodgate/config/FloodgateConfig.java

@@ -67,6 +67,7 @@ public class FloodgateConfig {
     @Getter
     public static class PlayerLinkConfig {
         private boolean enabled;
+        private boolean requireLink;
         private boolean enableOwnLinking = false;
         private boolean allowed;
         private long linkCodeTimeout;

common/src/main/java/org/geysermc/floodgate/player/FloodgateHandshakeHandler.java

@@ -143,6 +143,11 @@ public final class FloodgateHandshakeHandler {
             HandshakeData handshakeData = new HandshakeDataImpl(
                     channel, true, bedrockData.clone(), configHolder.get(),
                     linkedPlayer != null ? linkedPlayer.clone() : null, hostname);
+
+            if (configHolder.get().getPlayerLink().isRequireLink() && linkedPlayer == null) {
+                handshakeData.setDisconnectReason("floodgate.core.not_linked");
+            }
+
             handshakeHandlers.callHandshakeHandlers(handshakeData);
 
             if (!handshakeData.shouldDisconnect()) {

common/src/main/java/org/geysermc/floodgate/skin/SkinUploadSocket.java

@@ -32,6 +32,7 @@ import com.google.gson.JsonObject;
 import com.google.gson.JsonSyntaxException;
 import java.net.ConnectException;
 import java.net.URI;
+import javax.net.ssl.SSLException;
 import lombok.Getter;
 import org.geysermc.floodgate.api.FloodgateApi;
 import org.geysermc.floodgate.api.logger.FloodgateLogger;
@@ -138,8 +139,13 @@ final class SkinUploadSocket extends WebSocketClient {
 
     @Override
     public void onError(Exception exception) {
-        // skip can't connect exceptions and the syntax error in onClose because of that.
+        // skip can't connect exceptions and the syntax error in onClose that happens because of it.
-        if (exception instanceof ConnectException || exception instanceof JsonSyntaxException) {
+        // they might however help during debugging so we'll log them when debug is enabled
+        if (exception instanceof ConnectException || exception instanceof JsonSyntaxException ||
+                exception instanceof SSLException) {
+            if (logger.isDebug()) {
+                logger.error("[debug] Got an error", exception);
+            }
             return;
         }
         logger.error("Got an error", exception);

common/src/main/resources/config.yml

@@ -28,6 +28,9 @@ player-link:
   # players from using the linking feature even if they are already linked.
   enabled: true
 
+  # Whether to require a linked account in order to be able to join the server.
+  require-link: false
+
   # Uncomment the following line when you want to host your own linking database.
   # -> This can work in addition to global linking.
   # Note that you have to install a linking database implementation before enabling this, because