Paper/patches/server/0291-Don-t-allow-digging-into-unloaded-chunks.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Shane Freeder <theboyetronic@gmail.com>
Date: Sun, 11 Nov 2018 21:01:09 +0000
Subject: [PATCH] Don't allow digging into unloaded chunks


diff --git a/src/main/java/net/minecraft/server/level/ServerPlayerGameMode.java b/src/main/java/net/minecraft/server/level/ServerPlayerGameMode.java
index 1d1f355a49e2324902feee10c1717fd772e359c6..d0b54ebc05cac6535a023709c76efd802f7150f9 100644
--- a/src/main/java/net/minecraft/server/level/ServerPlayerGameMode.java
+++ b/src/main/java/net/minecraft/server/level/ServerPlayerGameMode.java
@@ -118,8 +118,8 @@ public class ServerPlayerGameMode {
         BlockState iblockdata;
 
         if (this.hasDelayedDestroy) {
-            iblockdata = this.level.getBlockState(this.delayedDestroyPos);
-            if (iblockdata.isAir()) {
+            iblockdata = this.level.getBlockStateIfLoaded(this.delayedDestroyPos); // Paper
+            if (iblockdata == null || iblockdata.isAir()) { // Paper
                 this.hasDelayedDestroy = false;
             } else {
                 float f = this.incrementDestroyProgress(iblockdata, this.delayedDestroyPos, this.delayedTickStart);
@@ -130,7 +130,13 @@ public class ServerPlayerGameMode {
                 }
             }
         } else if (this.isDestroyingBlock) {
-            iblockdata = this.level.getBlockState(this.destroyPos);
+            // Paper start - don't want to do same logic as above, return instead
+            iblockdata = this.level.getBlockStateIfLoaded(this.destroyPos);
+            if (iblockdata == null) {
+                this.isDestroyingBlock = false;
+                return;
+            }
+            // Paper end
             if (iblockdata.isAir()) {
                 this.level.destroyBlockProgress(this.player.getId(), this.destroyPos, -1);
                 this.lastSentState = -1;
@@ -162,6 +168,7 @@ public class ServerPlayerGameMode {
         double d3 = d0 * d0 + d1 * d1 + d2 * d2;
 
         if (d3 > 36.0D) {
+            if (true) return; // Paper - Don't notify if unreasonably far away
             this.player.connection.send(new ClientboundBlockBreakAckPacket(pos, this.level.getBlockState(pos), action, false, "too far"));
         } else if (pos.getY() >= worldHeight) {
             this.player.connection.send(new ClientboundBlockBreakAckPacket(pos, this.level.getBlockState(pos), action, false, "too high"));
@@ -294,10 +301,12 @@ public class ServerPlayerGameMode {
                 this.player.connection.send(new ClientboundBlockBreakAckPacket(pos, this.level.getBlockState(pos), action, true, "stopped destroying"));
             } else if (action == ServerboundPlayerActionPacket.Action.ABORT_DESTROY_BLOCK) {
                 this.isDestroyingBlock = false;
-                if (!Objects.equals(this.destroyPos, pos)) {
+                if (!Objects.equals(this.destroyPos, pos) && !BlockPos.ZERO.equals(this.destroyPos)) {
                     ServerPlayerGameMode.LOGGER.debug("Mismatch in destroy block pos: {} {}", this.destroyPos, pos); // CraftBukkit - SPIGOT-5457 sent by client when interact event cancelled
-                    this.level.destroyBlockProgress(this.player.getId(), this.destroyPos, -1);
-                    this.player.connection.send(new ClientboundBlockBreakAckPacket(this.destroyPos, this.level.getBlockState(this.destroyPos), action, true, "aborted mismatched destroying"));
+                    BlockState type = this.level.getBlockStateIfLoaded(this.destroyPos); // Paper - don't load unloaded chunks for stale records here
+                    if (type != null) this.level.destroyBlockProgress(this.player.getId(), this.destroyPos, -1); // Paper
+                    if (type != null) this.player.connection.send(new ClientboundBlockBreakAckPacket(this.destroyPos, type, action, true, "aborted mismatched destroying")); // Paper
+                    this.destroyPos = BlockPos.ZERO; // Paper
                 }
 
                 this.level.destroyBlockProgress(this.player.getId(), pos, -1);
diff --git a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
index ab5a6bba572bc27dbf9473cf7042c4cdef6843dc..7960a57c25dc80c6ca762e65c3ef82065cce2b7a 100644
--- a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
+++ b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
@@ -1550,7 +1550,12 @@ public class ServerGamePacketListenerImpl implements ServerPlayerConnection, Ser
             case START_DESTROY_BLOCK:
             case ABORT_DESTROY_BLOCK:
             case STOP_DESTROY_BLOCK:
+                // Paper start - Don't allow digging in unloaded chunks
+                if (this.player.level.getChunkIfLoadedImmediately(blockposition.getX() >> 4, blockposition.getZ() >> 4) == null) {
+                    return;
+                }
                 this.player.gameMode.handleBlockBreakAction(blockposition, packetplayinblockdig_enumplayerdigtype, packet.getDirection(), this.player.level.getMaxBuildHeight());
+                // Paper end - Don't allow digging in unloaded chunks
                 return;
             default:
                 throw new IllegalArgumentException("Invalid player action");