Paper/patches/server/0516-Limit-recipe-packets.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Shane Freeder <theboyetronic@gmail.com>
Date: Sat, 12 Dec 2020 23:45:28 +0000
Subject: [PATCH] Limit recipe packets


diff --git a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
index 4e9ae442a838e685e96d436e0f14ff2d1f5e81f4..ba07a2c243f833aa4e0370993cac25bdd13d53d4 100644
--- a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
+++ b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
@@ -262,6 +262,7 @@ public class ServerGamePacketListenerImpl implements ServerPlayerConnection, Tic
     // CraftBukkit start - multithreaded fields
     private final AtomicInteger chatSpamTickCount = new AtomicInteger();
     private final java.util.concurrent.atomic.AtomicInteger tabSpamLimiter = new java.util.concurrent.atomic.AtomicInteger(); // Paper - configurable tab spam limits
+    private final java.util.concurrent.atomic.AtomicInteger recipeSpamPackets =  new java.util.concurrent.atomic.AtomicInteger(); // Paper - auto recipe limit
     // CraftBukkit end
     private int dropSpamTickCount;
     private double firstGoodX;
@@ -414,6 +415,7 @@ public class ServerGamePacketListenerImpl implements ServerPlayerConnection, Tic
         // CraftBukkit start
         for (int spam; (spam = this.chatSpamTickCount.get()) > 0 && !this.chatSpamTickCount.compareAndSet(spam, spam - 1); ) ;
         if (tabSpamLimiter.get() > 0) tabSpamLimiter.getAndDecrement(); // Paper - split to seperate variable
+        if (recipeSpamPackets.get() > 0) recipeSpamPackets.getAndDecrement(); // Paper
         /* Use thread-safe field access instead
         if (this.chatSpamTickCount > 0) {
             --this.chatSpamTickCount;
@@ -3111,6 +3113,14 @@ public class ServerGamePacketListenerImpl implements ServerPlayerConnection, Tic
 
     @Override
     public void handlePlaceRecipe(ServerboundPlaceRecipePacket packet) {
+        // Paper start
+        if (!org.bukkit.Bukkit.isPrimaryThread()) {
+            if (recipeSpamPackets.addAndGet(io.papermc.paper.configuration.GlobalConfiguration.get().spamLimiter.recipeSpamIncrement) > io.papermc.paper.configuration.GlobalConfiguration.get().spamLimiter.recipeSpamLimit) {
+                server.scheduleOnMain(() -> this.disconnect(net.minecraft.network.chat.Component.translatable("disconnect.spam", new Object[0]))); // Paper
+                return;
+            }
+        }
+        // Paper end
         PacketUtils.ensureRunningOnSameThread(packet, this, this.player.getLevel());
         this.player.resetLastActionTime();
         if (!this.player.isSpectator() && this.player.containerMenu.containerId == packet.getContainerId() && this.player.containerMenu instanceof RecipeBookMenu) {