The uuid mapping database

README.md

@@ -9,11 +9,18 @@ A list of small tweaks I made:
 - Implement player UUID rewrite, like what bungeecord does. 
   Make setup with online velocity + offline Minecraft server work correctly
   (`online-mode=true` on velocity + `online-mode=false` on backend mc servers + `player-info-forwarding-mode=none`)
-  - TabList packets rewrite
-    - Affects `LegacyPlayerListItemPacket`, `UpsertPlayerInfoPacket`, `RemovePlayerInfoPacket` packets
-    - Rewrites player UUIDs inside those packets to their UUIDs in the velocity server
-  - Entity packets rewrite
-    - Rewrites player UUIDs inside player creation packets and spectator teleport packets, to their UUIDs in the velocity server
+  - Packets to rewrite:
+    - TabList packets
+      - Affects `LegacyPlayerListItemPacket`, `UpsertPlayerInfoPacket`, `RemovePlayerInfoPacket` packets
+      - Rewrites player UUIDs inside those packets to their UUIDs in the velocity server
+    - Entity packets
+      - Rewrites player UUIDs inside player creation packets and spectator teleport packets, to their UUIDs in the velocity server
+  - All related configs are under section `uuid-rewrite` in `velocity.toml`
+  - Optional external uuid mapping sqlite database support
+    - Enabled with `databaseEnabled = true`, database path configurable with `databasePath`
+    - Mapping between online / offline uuid will be updated on player connected
+    - The sqlite database file can be shared between multiple velocity instances
+  - UUID rewrite can be disabled by setting `enabled = false`
 
 # Velocity
 

gradle/libs.versions.toml

@@ -57,6 +57,7 @@ nightconfig = "com.electronwill.night-config:toml:3.6.7"
 slf4j = "org.slf4j:slf4j-api:2.0.12"
 snakeyaml = "org.yaml:snakeyaml:1.33"
 spotbugs-annotations = "com.github.spotbugs:spotbugs-annotations:4.7.3"
+sqlite-jdbc = "org.xerial:sqlite-jdbc:3.46.0.1"  # [fallen's fork] player uuid rewrite - uuid database
 terminalconsoleappender = "net.minecrell:terminalconsoleappender:1.3.0"
 
 [bundles]

proxy/build.gradle.kts

@@ -126,6 +126,7 @@ dependencies {
     implementation(libs.lmbda)
     implementation(libs.asm)
     implementation(libs.bundles.flare)
+    implementation(libs.sqlite.jdbc)  // [fallen's fork] player uuid rewrite - uuid database
     compileOnly(libs.spotbugs.annotations)
     compileOnly(libs.auto.service.annotations)
     testImplementation(libs.mockito)

proxy/src/main/java/com/velocitypowered/proxy/VelocityServer.java

@@ -53,7 +53,6 @@
 import com.velocitypowered.proxy.network.ConnectionManager;
 import com.velocitypowered.proxy.plugin.VelocityPluginManager;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
-import com.velocitypowered.proxy.protocol.packet.uuidrewrite.TabListUuidRewriter;
 import com.velocitypowered.proxy.protocol.util.FaviconSerializer;
 import com.velocitypowered.proxy.protocol.util.GameProfileSerializer;
 import com.velocitypowered.proxy.scheduler.VelocityScheduler;
@@ -64,6 +63,7 @@
 import com.velocitypowered.proxy.util.VelocityChannelRegistrar;
 import com.velocitypowered.proxy.util.ratelimit.Ratelimiter;
 import com.velocitypowered.proxy.util.ratelimit.Ratelimiters;
+import com.velocitypowered.proxy.uuidrewrite.UuidRewriteHooks;
 import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
 import io.netty.bootstrap.Bootstrap;
 import io.netty.channel.Channel;
@@ -264,6 +264,9 @@ void start() {
       this.cm.queryBind(configuration.getBind().getHostString(), configuration.getQueryPort());
     }
 
+    // [fallen's fork] player uuid rewrite - lifecycle hook
+    UuidRewriteHooks.onServerStart(this);
+
     Metrics.VelocityMetrics.startMetrics(this, configuration.getMetrics());
   }
 
@@ -513,6 +516,9 @@ public void shutdown(boolean explicitExit, Component reason) {
         player.disconnect(reason);
       }
 
+      // [fallen's fork] player uuid rewrite - lifecycle hook
+      UuidRewriteHooks.onServerStop(this);
+
       try {
         boolean timedOut = false;
 
@@ -643,6 +649,10 @@ public boolean registerConnection(ConnectedPlayer connection) {
       connectionsByName.put(lowerName, connection);
       connectionsByUuid.put(connection.getUniqueId(), connection);
     }
+
+    // [fallen's fork] player uuid rewrite - lifecycle hook
+    UuidRewriteHooks.onPlayerConnect(this, connection);
+
     return true;
   }
 
@@ -656,8 +666,8 @@ public void unregisterConnection(ConnectedPlayer connection) {
     connectionsByUuid.remove(connection.getUniqueId(), connection);
     connection.disconnected();
 
-    // [fallen's fork] player uuid rewrite -
-    TabListUuidRewriter.onPlayerDisconnect(this, connection);
+    // [fallen's fork] player uuid rewrite - lifecycle hook
+    UuidRewriteHooks.onPlayerDisconnect(this, connection);
   }
 
   @Override

proxy/src/main/java/com/velocitypowered/proxy/config/VelocityConfiguration.java

@@ -86,6 +86,9 @@ public class VelocityConfiguration implements ProxyConfig {
   // [fallen's fork] mojang auth proxy
   @Expose
   private final AuthProxy authProxy;
+  // [fallen's fork] player uuid rewrite
+  @Expose
+  private final UuidRewrite uuidRewrite;
 
   @Expose
   private final Query query;
@@ -99,11 +102,13 @@ public class VelocityConfiguration implements ProxyConfig {
 
   private VelocityConfiguration(Servers servers, ForcedHosts forcedHosts, Advanced advanced,
       AuthProxy authProxy,  // [fallen's fork] mojang auth proxy
+      UuidRewrite uuidRewrite,  // [fallen's fork] player uuid rewrite
       Query query, Metrics metrics) {
     this.servers = servers;
     this.forcedHosts = forcedHosts;
     this.advanced = advanced;
     this.authProxy = authProxy;  // [fallen's fork] mojang auth proxy
+    this.uuidRewrite = uuidRewrite;  // [fallen's fork] player uuid rewrite
     this.query = query;
     this.metrics = metrics;
   }
@@ -115,6 +120,7 @@ private VelocityConfiguration(String bind, String motd, int showMaxPlayers, bool
       boolean enablePlayerAddressLogging, Servers servers, ForcedHosts forcedHosts,
       Advanced advanced,
       AuthProxy authProxy,  // [fallen's fork] mojang auth proxy
+      UuidRewrite uuidRewrite,  // [fallen's fork] player uuid rewrite
       Query query, Metrics metrics, boolean forceKeyAuthentication) {
     this.bind = bind;
     this.motd = motd;
@@ -131,6 +137,7 @@ private VelocityConfiguration(String bind, String motd, int showMaxPlayers, bool
     this.forcedHosts = forcedHosts;
     this.advanced = advanced;
     this.authProxy = authProxy;  // [fallen's fork] mojang auth proxy
+    this.uuidRewrite = uuidRewrite;  // [fallen's fork] player uuid rewrite
     this.query = query;
     this.metrics = metrics;
     this.forceKeyAuthentication = forceKeyAuthentication;
@@ -431,6 +438,24 @@ public int getAuthProxyPort() {
   }
   // [fallen's fork] mojang auth proxy ends
 
+  // [fallen's fork] player uuid rewrite starts
+  public boolean isUuidRewriteEnabled() {
+    return uuidRewrite.isEnabled();
+  }
+
+  public boolean isUuidRewriteDatabaseEnabled() {
+    return uuidRewrite.isDatabaseEnabled();
+  }
+
+  public void setUuidRewriteDatabaseEnabled(boolean b) {
+    uuidRewrite.setDatabaseEnabled(b);
+  }
+
+  public String getUuidRewriteDatabasePath() {
+    return uuidRewrite.getDatabasePath();
+  }
+  // [fallen's fork] player uuid rewrite ends
+
   public boolean isForceKeyAuthentication() {
     return forceKeyAuthentication;
   }
@@ -524,7 +549,8 @@ public static VelocityConfiguration read(Path path) throws IOException {
       final CommentedConfig serversConfig = config.get("servers");
       final CommentedConfig forcedHostsConfig = config.get("forced-hosts");
       final CommentedConfig advancedConfig = config.get("advanced");
-      final CommentedConfig autoProxy = config.get("auth-proxy");
+      final CommentedConfig autoProxy = config.get("auth-proxy");  // [fallen's fork] mojang auth proxy
+      final CommentedConfig uuidRewrite = config.get("uuid-rewrite");  // [fallen's fork] player uuid rewrite
       final CommentedConfig queryConfig = config.get("query");
       final CommentedConfig metricsConfig = config.get("metrics");
       final PlayerInfoForwarding forwardingMode = config.getEnumOrElse(
@@ -566,7 +592,8 @@ public static VelocityConfiguration read(Path path) throws IOException {
               new Servers(serversConfig),
               new ForcedHosts(forcedHostsConfig),
               new Advanced(advancedConfig),
-              new AuthProxy(autoProxy),
+              new AuthProxy(autoProxy),  // [fallen's fork] mojang auth proxy
+              new UuidRewrite(uuidRewrite),  // [fallen's fork] player uuid rewrite
               new Query(queryConfig),
               new Metrics(metricsConfig),
               forceKeyAuthentication
@@ -894,6 +921,42 @@ public int getPort() {
     }
   }
 
+  /**
+   * [fallen's fork] player uuid rewrite - config.
+   */
+  private static class UuidRewrite {
+    @Expose
+    private boolean enabled = true;
+    @Expose
+    private boolean databaseEnabled = false;
+    @Expose
+    private String databasePath = "uuid_mapping.db";
+
+    public UuidRewrite(CommentedConfig config) {
+      if (config != null) {
+        this.enabled = config.getOrElse("enabled", true);
+        this.databaseEnabled = config.getOrElse("databaseEnabled", false);
+        this.databasePath = config.getOrElse("databasePath", "uuid_mapping.db");
+      }
+    }
+
+    public boolean isEnabled() {
+      return enabled;
+    }
+
+    public boolean isDatabaseEnabled() {
+      return databaseEnabled;
+    }
+
+    public void setDatabaseEnabled(boolean databaseEnabled) {
+      this.databaseEnabled = databaseEnabled;
+    }
+
+    public String getDatabasePath() {
+      return databasePath;
+    }
+  }
+
   private static class Query {
 
     @Expose

proxy/src/main/java/com/velocitypowered/proxy/connection/backend/BackendPlaySessionHandler.java

@@ -66,11 +66,11 @@
 import com.velocitypowered.proxy.protocol.packet.UpsertPlayerInfoPacket;
 import com.velocitypowered.proxy.protocol.packet.chat.ComponentHolder;
 import com.velocitypowered.proxy.protocol.packet.config.StartUpdatePacket;
-import com.velocitypowered.proxy.protocol.packet.uuidrewrite.EntityPacketUuidRewriter;
-import com.velocitypowered.proxy.protocol.packet.uuidrewrite.TabListUuidRewriter;
 import com.velocitypowered.proxy.protocol.packet.uuidrewrite.UrSpawnEntityS2CPacket;
 import com.velocitypowered.proxy.protocol.packet.uuidrewrite.UrSpawnPlayerS2CPacket;
 import com.velocitypowered.proxy.protocol.util.PluginMessageUtil;
+import com.velocitypowered.proxy.uuidrewrite.EntityPacketUuidRewriter;
+import com.velocitypowered.proxy.uuidrewrite.TabListUuidRewriter;
 import io.netty.buffer.ByteBuf;
 import io.netty.buffer.ByteBufUtil;
 import io.netty.buffer.Unpooled;

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

@@ -72,10 +72,10 @@
 import com.velocitypowered.proxy.protocol.packet.chat.session.SessionPlayerCommandPacket;
 import com.velocitypowered.proxy.protocol.packet.config.FinishedUpdatePacket;
 import com.velocitypowered.proxy.protocol.packet.title.GenericTitlePacket;
-import com.velocitypowered.proxy.protocol.packet.uuidrewrite.EntityPacketUuidRewriter;
 import com.velocitypowered.proxy.protocol.packet.uuidrewrite.UrSpectatorTeleportC2SPacket;
 import com.velocitypowered.proxy.protocol.util.PluginMessageUtil;
 import com.velocitypowered.proxy.util.CharacterUtil;
+import com.velocitypowered.proxy.uuidrewrite.EntityPacketUuidRewriter;
 import io.netty.buffer.ByteBuf;
 import io.netty.buffer.ByteBufUtil;
 import io.netty.buffer.Unpooled;