Waterfall/BungeeCord-Patches/0047-Provide-an-option-to-disable-entity-metadata-rewriti.patch

From 986cade2e09a89dc837a876a88ffe3656fc54545 Mon Sep 17 00:00:00 2001
From: Shane Freeder <theboyetronic@gmail.com>
Date: Mon, 14 Jan 2019 03:35:21 +0000
Subject: [PATCH] Provide an option to disable entity metadata rewriting

The work here is derived from the research and guidance of
various members of the minecraft community

This patch provides the ability to disable entity remapping,
which creates various incompatability issues with mods, however,
may also create various issues with mods which do not support this,
hence why the configuration option is provided

diff --git a/api/src/main/java/net/md_5/bungee/api/ProxyConfig.java b/api/src/main/java/net/md_5/bungee/api/ProxyConfig.java
index 46adc983..0e69db36 100644
--- a/api/src/main/java/net/md_5/bungee/api/ProxyConfig.java
+++ b/api/src/main/java/net/md_5/bungee/api/ProxyConfig.java
@@ -214,4 +214,9 @@ public interface ProxyConfig
      * @return should we allow empty packets
      */
     boolean isAllowEmptyPackets();
+
+    /**
+     * @return Should we disable entity metadata rewriting?
+     */
+    boolean isDisableEntityMetadataRewrite();
 }
diff --git a/proxy/src/main/java/io/github/waterfallmc/waterfall/conf/WaterfallConfiguration.java b/proxy/src/main/java/io/github/waterfallmc/waterfall/conf/WaterfallConfiguration.java
index f28f0111..41a71f65 100644
--- a/proxy/src/main/java/io/github/waterfallmc/waterfall/conf/WaterfallConfiguration.java
+++ b/proxy/src/main/java/io/github/waterfallmc/waterfall/conf/WaterfallConfiguration.java
@@ -53,6 +53,8 @@ public class WaterfallConfiguration extends Configuration {
      */
     private boolean allowEmptyPackets = false;
 
+    private boolean disableEntityMetadataRewrite = false;
+
     @Override
     public void load() {
         super.load();
@@ -65,6 +67,7 @@ public class WaterfallConfiguration extends Configuration {
         tabThrottle = config.getInt("throttling.tab_complete", tabThrottle);
         disableModernTabLimiter = config.getBoolean("disable_modern_tab_limiter", disableModernTabLimiter);
         allowEmptyPackets = config.getBoolean("allow_empty_packets", allowEmptyPackets);
+        disableEntityMetadataRewrite = config.getBoolean("disable_entity_metadata_rewrite", disableEntityMetadataRewrite);
     }
 
     @Override
@@ -96,4 +99,9 @@ public class WaterfallConfiguration extends Configuration {
     public boolean isAllowEmptyPackets() {
         return allowEmptyPackets;
     }
+
+    @Override
+    public boolean isDisableEntityMetadataRewrite() {
+        return disableEntityMetadataRewrite;
+    }
 }
diff --git a/proxy/src/main/java/net/md_5/bungee/ServerConnector.java b/proxy/src/main/java/net/md_5/bungee/ServerConnector.java
index c2b1de82..1375d1e2 100644
--- a/proxy/src/main/java/net/md_5/bungee/ServerConnector.java
+++ b/proxy/src/main/java/net/md_5/bungee/ServerConnector.java
@@ -226,7 +226,7 @@ public class ServerConnector extends PacketHandler
             ch.write( message );
         }
 
-        if ( user.getSettings() != null )
+        if (!user.isDisableEntityMetadataRewrite() && user.getSettings() != null )
         {
             ch.write( user.getSettings() );
         }
@@ -260,6 +260,7 @@ public class ServerConnector extends PacketHandler
             user.getTabListHandler().onServerChange();
 
             Scoreboard serverScoreboard = user.getServerSentScoreboard();
+            if ( !user.isDisableEntityMetadataRewrite() ) { // Waterfall
             for ( Objective objective : serverScoreboard.getObjectives() )
             {
                 user.unsafe().sendPacket( new ScoreboardObjective( objective.getName(), objective.getValue(), ScoreboardObjective.HealthDisplay.fromString( objective.getType() ), (byte) 1 ) );
@@ -272,6 +273,7 @@ public class ServerConnector extends PacketHandler
             {
                 user.unsafe().sendPacket( new net.md_5.bungee.protocol.packet.Team( team.getName() ) );
             }
+            } // Waterfall
             serverScoreboard.clear();
 
             for ( UUID bossbar : user.getSentBossBars() )
@@ -285,12 +287,27 @@ public class ServerConnector extends PacketHandler
             user.unsafe().sendPacket( new EntityStatus( user.getClientEntityId(), login.isReducedDebugInfo() ? EntityStatus.DEBUG_INFO_REDUCED : EntityStatus.DEBUG_INFO_NORMAL ) );
 
             user.setDimensionChange( true );
-            if ( login.getDimension() == user.getDimension() )
+            if ( !user.isDisableEntityMetadataRewrite() && login.getDimension() == user.getDimension() ) // Waterfall - defer
             {
                 user.unsafe().sendPacket( new Respawn( ( login.getDimension() >= 0 ? -1 : 0 ), login.getDifficulty(), login.getGameMode(), login.getLevelType() ) );
             }
 
             user.setServerEntityId( login.getEntityId() );
+            // Waterfall start
+            if ( user.isDisableEntityMetadataRewrite() ) {
+                // Ensure that we maintain consistency
+                user.setClientEntityId( login.getEntityId() );
+
+                Login modLogin = new Login( login.getEntityId(),login.getGameMode(), login.getDimension(),
+                        login.getDifficulty(), login.getMaxPlayers(), login.getLevelType(), login.getViewDistance(), login.isReducedDebugInfo() );
+                user.unsafe().sendPacket(modLogin);
+
+                // Only send if we're in the same dimension
+                if (user.getDimension() == login.getDimension()) {
+                    user.unsafe().sendPacket( new Respawn(user.getDimension() == 0 ? -1 : 0, login.getDifficulty(), login.getGameMode(), login.getLevelType()));
+                }
+            }
+            // Waterfall end
             user.unsafe().sendPacket( new Respawn( login.getDimension(), login.getDifficulty(), login.getGameMode(), login.getLevelType() ) );
             if ( user.getPendingConnection().getVersion() >= ProtocolConstants.MINECRAFT_1_14 )
             {
diff --git a/proxy/src/main/java/net/md_5/bungee/UserConnection.java b/proxy/src/main/java/net/md_5/bungee/UserConnection.java
index 74aa4f3e..7e9678d9 100644
--- a/proxy/src/main/java/net/md_5/bungee/UserConnection.java
+++ b/proxy/src/main/java/net/md_5/bungee/UserConnection.java
@@ -145,6 +145,7 @@ public final class UserConnection implements ProxiedPlayer
     @Setter
     private ForgeServerHandler forgeServerHandler;
     /*========================================================================*/
+    private boolean disableEntityMetadaRewrite;
     private final Unsafe unsafe = new Unsafe()
     {
         @Override
@@ -156,6 +157,13 @@ public final class UserConnection implements ProxiedPlayer
 
     public void init()
     {
+        // Waterfall start
+        disableEntityMetadaRewrite = bungee.getConfig().isDisableEntityMetadataRewrite();
+        if ( disableEntityMetadaRewrite )
+        {
+            entityRewrite = net.md_5.bungee.entitymap.EntityMap_Dummy.INSTANCE;
+        } else
+        // Waterfall end
         this.entityRewrite = EntityMap.getEntityMap( getPendingConnection().getVersion() );
 
         this.displayName = name;
@@ -730,4 +738,10 @@ public final class UserConnection implements ProxiedPlayer
     {
         return serverSentScoreboard;
     }
+
+    // Waterfall start
+    public boolean isDisableEntityMetadataRewrite() {
+        return disableEntityMetadaRewrite;
+    }
+    // Waterfall end
 }
diff --git a/proxy/src/main/java/net/md_5/bungee/connection/DownstreamBridge.java b/proxy/src/main/java/net/md_5/bungee/connection/DownstreamBridge.java
index fd14f518..fba84905 100644
--- a/proxy/src/main/java/net/md_5/bungee/connection/DownstreamBridge.java
+++ b/proxy/src/main/java/net/md_5/bungee/connection/DownstreamBridge.java
@@ -588,6 +588,7 @@ public class DownstreamBridge extends PacketHandler
     @Override
     public void handle(EntityEffect entityEffect) throws Exception
     {
+        if (con.isDisableEntityMetadataRewrite()) return; // Waterfall
         // Don't send any potions when switching between servers (which involves a handshake), which can trigger a race
         // condition on the client.
         if (this.con.getForgeClientHandler().isForgeUser() && !this.con.getForgeClientHandler().isHandshakeComplete()) {
@@ -599,6 +600,7 @@ public class DownstreamBridge extends PacketHandler
     @Override
     public void handle(EntityRemoveEffect removeEffect) throws Exception
     {
+        if (con.isDisableEntityMetadataRewrite()) return; // Waterfall
         con.getPotions().remove(rewriteEntityId(removeEffect.getEntityId()), removeEffect.getEffectId());
     }
 
diff --git a/proxy/src/main/java/net/md_5/bungee/entitymap/EntityMap.java b/proxy/src/main/java/net/md_5/bungee/entitymap/EntityMap.java
index e67c0034..45a9686a 100644
--- a/proxy/src/main/java/net/md_5/bungee/entitymap/EntityMap.java
+++ b/proxy/src/main/java/net/md_5/bungee/entitymap/EntityMap.java
@@ -273,7 +273,13 @@ public abstract class EntityMap
                     DefinedPacket.readVarInt( packet );
                     break;
                 default:
-                    throw new IllegalArgumentException( "Unknown meta type " + type );
+                    // Waterfall start - Don't lie
+                    if ( protocolVersion >= ProtocolConstants.MINECRAFT_1_13 )
+                    {
+                        type++;
+                    }
+                    throw new IllegalArgumentException( "Unknown meta type " + type  + ": Using mods? refer to disable_entity_metadata_rewrite in waterfall.yml" );
+                    // Waterfall end
             }
         }
 
diff --git a/proxy/src/main/java/net/md_5/bungee/entitymap/EntityMap_Dummy.java b/proxy/src/main/java/net/md_5/bungee/entitymap/EntityMap_Dummy.java
new file mode 100644
index 00000000..cb81d1dd
--- /dev/null
+++ b/proxy/src/main/java/net/md_5/bungee/entitymap/EntityMap_Dummy.java
@@ -0,0 +1,30 @@
+
+package net.md_5.bungee.entitymap;
+
+import io.netty.buffer.ByteBuf;
+// Waterfall start
+
+public class EntityMap_Dummy extends EntityMap {
+
+    public static final EntityMap_Dummy INSTANCE = new EntityMap_Dummy();
+
+    EntityMap_Dummy() {
+    }
+
+    @Override
+    public void rewriteServerbound(ByteBuf packet, int oldId, int newId) {
+    }
+
+    @Override
+    public void rewriteServerbound(ByteBuf packet, int oldId, int newId, int protocolVersion) {
+    }
+
+    @Override
+    public void rewriteClientbound(ByteBuf packet, int oldId, int newId) {
+    }
+
+    @Override
+    public void rewriteClientbound(ByteBuf packet, int oldId, int newId, int protocolVersion) {
+    }
+}
+// Waterfall end
\ No newline at end of file
-- 
2.21.0