Change authentication

src/main/java/fi/flexplex/connect/FlexConnect.java

@@ -3,7 +3,9 @@ package fi.flexplex.connect;
 import java.io.FileInputStream;
 import java.io.FileOutputStream;
 import java.io.IOException;
+import java.util.HashSet;
 import java.util.Properties;
+import java.util.Set;
 
 import org.bukkit.configuration.file.YamlConfiguration;
 import org.bukkit.plugin.java.JavaPlugin;
@@ -12,6 +14,8 @@ import fi.flexplex.connect.util.FileChangeListener;
 
 public final class FlexConnect extends JavaPlugin {
 
+    private final Set<String> proxyAddresses = new HashSet<>();
+
     private String token = "";
     private FlexPlexGraphQLApi flexPlexGraphQLApi;
 
@@ -23,6 +27,10 @@ public final class FlexConnect extends JavaPlugin {
         return this.flexPlexGraphQLApi;
     }
 
+    public Set<String> getProxyAddresses() {
+        return this.proxyAddresses;
+    }
+
     @Override
     public void onEnable() {
 
@@ -86,6 +94,13 @@ public final class FlexConnect extends JavaPlugin {
 
         // Update whitelists for flexplex api
         this.flexPlexGraphQLApi.updateWhitelist();
+
+        // Load real FlexPlex proxy addresses from FlexPlex API
+        this.proxyAddresses.addAll(this.flexPlexGraphQLApi.getProxyAddresses());
+
+        // Load allowed proxy addresses from config
+        this.proxyAddresses.addAll(this.getConfig().getStringList("allowedProxies"));
+
     }
 
 }

src/main/java/fi/flexplex/connect/FlexConnectListener.java

@@ -1,13 +1,12 @@
 package fi.flexplex.connect;
 
 import com.destroystokyo.paper.event.server.WhitelistToggleEvent;
-import com.destroystokyo.paper.profile.ProfileProperty;
 
 import org.bukkit.Bukkit;
 import org.bukkit.event.EventHandler;
 import org.bukkit.event.EventPriority;
 import org.bukkit.event.Listener;
-import org.bukkit.event.player.AsyncPlayerPreLoginEvent;
+import org.bukkit.event.player.PlayerLoginEvent;
 
 import fi.flexplex.connect.event.AsyncWhitelistChangedEvent;
 
@@ -20,16 +19,14 @@ public final class FlexConnectListener implements Listener {
     }
 
     @EventHandler
-    public void onAsyncPlayerPreLogin(final AsyncPlayerPreLoginEvent event) {
-        // Authenticate players
-        for (final ProfileProperty property : event.getPlayerProfile().getProperties()) {
-            if (property.getName().equals("flexplex-token") && property.getValue().equals(flexConnect.getToken())) {
-                // Authentication success
-                return;
-            }
+    public void onPlayerLogin(final PlayerLoginEvent event) {
+        if (flexConnect.getProxyAddresses().contains(event.getRealAddress().getHostAddress())) {
+            // Connection is coming from allowed proxy
+            return;
         }
-        // Authentication failed
-        event.disallow(AsyncPlayerPreLoginEvent.Result.KICK_OTHER, "Access denied");
+
+        // Do not allow connections from other proxies
+        event.disallow(PlayerLoginEvent.Result.KICK_OTHER, "Access denied");
     }
 
     @EventHandler(ignoreCancelled = true, priority = EventPriority.MONITOR)

src/main/java/fi/flexplex/connect/FlexPlexGraphQLApi.java

@@ -10,6 +10,7 @@ import java.util.HashSet;
 import java.util.Set;
 import java.util.UUID;
 
+import com.google.gson.JsonArray;
 import com.google.gson.JsonObject;
 import com.google.gson.JsonParser;
 
@@ -25,6 +26,40 @@ public final class FlexPlexGraphQLApi {
         this.graphqlEndpoint = graphQLEndpoint;
     }
 
+    public Set<String> getProxyAddresses() {
+        final Set<String> output = new HashSet<>();
+        try {
+            final URL url = new URL(graphqlEndpoint);
+            final HttpURLConnection conn = (HttpURLConnection) url.openConnection();
+            conn.setDoOutput(true);
+            conn.setDoInput(true);
+            conn.setConnectTimeout(10000);
+            conn.setReadTimeout(10000);
+            conn.setRequestMethod("POST");
+            conn.setRequestProperty("Content-Type", "application/json");
+
+            final DataOutputStream wr = new DataOutputStream(conn.getOutputStream());
+            
+            wr.writeBytes("{\"query\":\"query { proxyAddresses }\"}");
+            wr.flush();
+            wr.close();
+
+            final JsonObject response = (JsonObject) new JsonParser().parse(new InputStreamReader(conn.getInputStream(), StandardCharsets.UTF_8));
+
+            if (response.get("data").getAsJsonObject().has("proxyAddresses")) {
+                final JsonArray array = response.get("data").getAsJsonObject().get("proxyAddresses").getAsJsonArray();
+                for (int i = 0; i < array.size(); i++) {
+                    output.add(array.get(i).getAsString());
+                }
+            }
+
+            conn.disconnect();
+        } catch (final IOException e) {
+            this.flexConnect.getLogger().warning("Updating whitelist data failed, propably connection to FlexPlex API server is down.");
+        }
+        return output;
+    }
+
     public void updateWhitelist() {
         this.updateWhitelist(this.flexConnect.getServer().hasWhitelist());
     }

src/main/resources/config.yml

@@ -1 +1,3 @@
 token: "default"
+
+allowedProxies: []