Allow enabling sand duping (#10191)

Because this exploit has been widely known for years and has not been fixed by Mojang, we decided that it was worth allowing people to toggle it on/off due to how easy it is to make it configurable.

It should be noted that this decision does not promise all future exploits will be configurable.

patches/server/0005-Paper-config-files.patch

@@ -482,10 +482,10 @@ index 0000000000000000000000000000000000000000..c01b4393439838976965823298f12e47
 +}
 diff --git a/src/main/java/io/papermc/paper/configuration/GlobalConfiguration.java b/src/main/java/io/papermc/paper/configuration/GlobalConfiguration.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..57e6e857c84234bf0c137058ae35e6fb0e9b124f
+index 0000000000000000000000000000000000000000..7a53374319d5495253f277199114eaf43097456d
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/configuration/GlobalConfiguration.java
-@@ -0,0 +1,309 @@
+@@ -0,0 +1,311 @@
 +package io.papermc.paper.configuration;
 +
 +import co.aikar.timings.MinecraftTimings;
@@ -635,6 +635,8 @@ index 0000000000000000000000000000000000000000..57e6e857c84234bf0c137058ae35e6fb
 +    public UnsupportedSettings unsupportedSettings;
 +
 +    public class UnsupportedSettings extends ConfigurationPart {
++        @Comment("This setting allows for exploits related to end portals, for example sand duping")
++        public boolean allowUnsafeEndPortalTeleportation = false;
 +        @Comment("This setting controls if players should be able to break bedrock, end portals and other intended to be permanent blocks.")
 +        public boolean allowPermanentBlockBreakExploits = false;
 +        @Comment("This setting controls if player should be able to use TNT duplication, but this also allows duplicating carpet, rails and potentially other items")

patches/server/0382-Fix-sand-duping.patch

@@ -1,36 +0,0 @@
-From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
-From: Spottedleaf <Spottedleaf@users.noreply.github.com>
-Date: Fri, 12 Jun 2020 13:33:19 -0700
-Subject: [PATCH] Fix sand duping
-
-If the falling block dies during teleportation (entity#move), then we need
-to detect that by placing a check after the move.
-
-diff --git a/src/main/java/net/minecraft/world/entity/item/FallingBlockEntity.java b/src/main/java/net/minecraft/world/entity/item/FallingBlockEntity.java
-index c0477f913867c67809978a4f240303151d81e6ea..33cc2d1a4723ec07c4201eb6e0080d5e0281e1f0 100644
---- a/src/main/java/net/minecraft/world/entity/item/FallingBlockEntity.java
-+++ b/src/main/java/net/minecraft/world/entity/item/FallingBlockEntity.java
-@@ -132,6 +132,11 @@ public class FallingBlockEntity extends Entity {
- 
-     @Override
-     public void tick() {
-+        // Paper start - fix sand duping
-+        if (this.isRemoved()) {
-+            return;
-+        }
-+        // Paper end - fix sand duping
-         if (this.blockState.isAir()) {
-             this.discard(EntityRemoveEvent.Cause.DESPAWN); // CraftBukkit - add Bukkit remove cause
-         } else {
-@@ -143,6 +148,11 @@ public class FallingBlockEntity extends Entity {
-             }
- 
-             this.move(MoverType.SELF, this.getDeltaMovement());
-+            // Paper start - fix sand duping
-+            if (this.isRemoved()) {
-+                return;
-+            }
-+            // Paper end - fix sand duping
-             // Paper start - Configurable falling blocks height nerf
-             if (this.level().paperConfig().fixes.fallingBlockHeightNerf.test(v -> this.getY() > v)) {
-                 if (this.dropItem && this.level().getGameRules().getBoolean(GameRules.RULE_DOENTITYDROPS)) {

patches/server/0383-Prevent-position-desync-causing-tp-exploit.patch

@@ -13,7 +13,7 @@ behaviour, we need to move all of this dangerous logic outside
 of the move call and into an appropriate place in the tick method.
 
 diff --git a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
-index 874a1998b6aaff9f4c7818481298ad51e1adc525..67470ad0c09ae94e5fab775a28cdefdf1241c5fa 100644
+index c0907af0169862702a4f28985d141c0acb506f51..2eeeb1f1b07db439a68d70c55192aa9fb54f620c 100644
 --- a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
 +++ b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
 @@ -1366,6 +1366,11 @@ public class ServerGamePacketListenerImpl extends ServerCommonPacketListenerImpl

patches/server/0388-Add-permission-for-command-blocks.patch

@@ -18,7 +18,7 @@ index e8b12b27e5ec74afb940f575e5ce78e5905d55f4..c3eb4b6372eed0b7eb636f495ce494b6
                  return false;
              } else if (this.player.blockActionRestricted(this.level, pos, this.gameModeForPlayer)) {
 diff --git a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
-index 98826ba4ab062e029359968c221ba320b2d2daeb..e9a3edbb66c79664f35150f052b6ff3534d0904c 100644
+index 80b6871516c45291f63b1ae521dcdf34199fd9b4..d78d411879275f11f395b4f9c94b7aab88342236 100644
 --- a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
 +++ b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
 @@ -778,7 +778,7 @@ public class ServerGamePacketListenerImpl extends ServerCommonPacketListenerImpl

patches/server/0396-Convert-legacy-attributes-in-Item-Meta.patch

@@ -30,7 +30,7 @@ index d4dba8c733c7560e5108b8d239b52e593f8debec..ea48f1119a940056c37d1d203437bfbf
      public CraftAttributeMap(AttributeMap handle) {
          this.handle = handle;
 diff --git a/src/main/java/org/bukkit/craftbukkit/inventory/CraftMetaItem.java b/src/main/java/org/bukkit/craftbukkit/inventory/CraftMetaItem.java
-index 629fa76e6c7c2ede36ab855bb3a7a65dfd601449..a3713c5ab624b8d54ddcd69ae7587346ebbaed69 100644
+index 7cf1153ae532a9d53ee85b05f77ed74b94cf5fbc..27be5da67801be6fd99c91576064e4be0b3f0d6c 100644
 --- a/src/main/java/org/bukkit/craftbukkit/inventory/CraftMetaItem.java
 +++ b/src/main/java/org/bukkit/craftbukkit/inventory/CraftMetaItem.java
 @@ -485,7 +485,7 @@ class CraftMetaItem implements ItemMeta, Damageable, Repairable, BlockDataMeta {

patches/server/0412-Brand-support.patch

@@ -57,7 +57,7 @@ index e69043316372d98b122ed3788fda79cdd36849e8..6597e6e9987ddb5906909c22704fdfb6
              } catch (Exception ex) {
                  ServerGamePacketListenerImpl.LOGGER.error("Couldn\'t dispatch custom payload", ex);
 diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java
-index d6bddec130167af3d72555535045568ee941bb88..6e9fc623f5a56753e2c78c3ff63c6f4de7cbcccb 100644
+index 5ba0fa6fda6d496f7540185e6dc58439cc1e04f1..16d1338df730fd66c079b66117cbef91786f2146 100644
 --- a/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java
 +++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java
 @@ -3056,6 +3056,13 @@ public class CraftPlayer extends CraftHumanEntity implements Player {

patches/server/0413-Add-playPickupItemAnimation-to-LivingEntity.patch

@@ -5,7 +5,7 @@ Subject: [PATCH] Add playPickupItemAnimation to LivingEntity
 
 
 diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftLivingEntity.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftLivingEntity.java
-index 9a9d119e76fca75a9e531f4bbd204ab8eb9a1263..bf581842476b8f554987b452c291a55a1dfc92c5 100644
+index c4db692fb5d952e4d185067388fd46ed0e1f1537..e07553c3ee28a2510c46a8188c8ce507f2567c80 100644
 --- a/src/main/java/org/bukkit/craftbukkit/entity/CraftLivingEntity.java
 +++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftLivingEntity.java
 @@ -949,5 +949,10 @@ public class CraftLivingEntity extends CraftEntity implements LivingEntity {

patches/server/0415-Fix-SpawnChangeEvent-not-firing-for-all-use-cases.patch

@@ -5,7 +5,7 @@ Subject: [PATCH] Fix SpawnChangeEvent not firing for all use-cases
 
 
 diff --git a/src/main/java/net/minecraft/server/level/ServerLevel.java b/src/main/java/net/minecraft/server/level/ServerLevel.java
-index d2da284aa7284c5205e656c48262061980893be6..aa2f23c4f7d25d0f92ff025bb1840aff1b053fa3 100644
+index 9af1877321356348ad96b92ae8c5f4811bef50ac..2e42e09d3fa19e5a16374ee6ac1677dd2b2004f1 100644
 --- a/src/main/java/net/minecraft/server/level/ServerLevel.java
 +++ b/src/main/java/net/minecraft/server/level/ServerLevel.java
 @@ -1726,9 +1726,11 @@ public class ServerLevel extends Level implements WorldGenLevel {

patches/server/0418-Prevent-headless-pistons-from-being-created.patch

@@ -6,7 +6,7 @@ Subject: [PATCH] Prevent headless pistons from being created
 Prevent headless pistons from being created by explosions or tree/mushroom growth.
 
 diff --git a/src/main/java/net/minecraft/world/level/Explosion.java b/src/main/java/net/minecraft/world/level/Explosion.java
-index b03b4d366cae39081a7b70524e8615c986d76362..cd939ab6958e8eb632056d32f68e2fcae7735d64 100644
+index b057a67a416928ae30bd407b3da982b73ae3be03..2d1fe6af7923ad4a0143f2d3fd28abc85e6092c1 100644
 --- a/src/main/java/net/minecraft/world/level/Explosion.java
 +++ b/src/main/java/net/minecraft/world/level/Explosion.java
 @@ -205,6 +205,15 @@ public class Explosion {

patches/server/0428-Fix-Entity-Teleportation-and-cancel-velocity-if-tele.patch

@@ -31,7 +31,7 @@ index 789576f8b7b3001c243972b320b7dffbbf3baa5f..3b73565d295c09a5ab0d610338498f01
      }
  
 diff --git a/src/main/java/net/minecraft/world/entity/Entity.java b/src/main/java/net/minecraft/world/entity/Entity.java
-index dfea1879b8ab8d12bc7530ccf409f4d24978105d..a3d1f7ccac58cfec8f50dbdb3a620daa4894fffb 100644
+index 11a9142962637af5e26939a5eb8f35ba5f205793..f839ab6dea7f1efd59f22bcef91d4e279b1c232a 100644
 --- a/src/main/java/net/minecraft/world/entity/Entity.java
 +++ b/src/main/java/net/minecraft/world/entity/Entity.java
 @@ -162,6 +162,7 @@ public abstract class Entity implements Nameable, EntityAccess, CommandSource, S

patches/server/0431-Extend-block-drop-capture-to-capture-all-items-added.patch

@@ -6,7 +6,7 @@ Subject: [PATCH] Extend block drop capture to capture all items added to the
 
 
 diff --git a/src/main/java/net/minecraft/server/level/ServerLevel.java b/src/main/java/net/minecraft/server/level/ServerLevel.java
-index aa2f23c4f7d25d0f92ff025bb1840aff1b053fa3..a668e204946943bcc963ad41ea3029111267eef9 100644
+index 2e42e09d3fa19e5a16374ee6ac1677dd2b2004f1..283f686364691f54d9e9e925b33238526de74219 100644
 --- a/src/main/java/net/minecraft/server/level/ServerLevel.java
 +++ b/src/main/java/net/minecraft/server/level/ServerLevel.java
 @@ -1224,6 +1224,12 @@ public class ServerLevel extends Level implements WorldGenLevel {

patches/server/0437-Reset-Ender-Crystals-on-Dragon-Spawn.patch

@@ -11,7 +11,7 @@ This ensures the crystals/pillars are in expected state when the dragon spawns.
 See #3522
 
 diff --git a/src/main/java/net/minecraft/world/level/dimension/end/EndDragonFight.java b/src/main/java/net/minecraft/world/level/dimension/end/EndDragonFight.java
-index cad7a1b28c9d7a3e67dbf0865cbf232ebd39a8d9..3953bbfdaf3e93468108d194c215e6242e14f067 100644
+index 1c716cf65d77e54ba8f90c8cf736e20c64f5df2e..f615b7f43f1444cf1e34b92cb0c05242a5dc26fd 100644
 --- a/src/main/java/net/minecraft/world/level/dimension/end/EndDragonFight.java
 +++ b/src/main/java/net/minecraft/world/level/dimension/end/EndDragonFight.java
 @@ -472,6 +472,7 @@ public class EndDragonFight {

patches/server/0438-Fix-for-large-move-vectors-crashing-server.patch

@@ -6,7 +6,7 @@ Subject: [PATCH] Fix for large move vectors crashing server
 Check movement distance also based on current position.
 
 diff --git a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
-index 4e37b9a495babec58f60b59db0e034d5e033b198..5e605b9bdb76ca0c9529e7351432578855cc7fa2 100644
+index 3b73565d295c09a5ab0d610338498f01c7b1520d..e08c3e0d09896da60cbec7923882bc2263de1bae 100644
 --- a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
 +++ b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
 @@ -472,9 +472,9 @@ public class ServerGamePacketListenerImpl extends ServerCommonPacketListenerImpl

patches/server/0441-Retain-block-place-order-when-capturing-blockstates.patch

@@ -10,7 +10,7 @@ In general, look at making this logic more robust (i.e properly handling
 cases where a captured entry is overriden) - but for now this will do.
 
 diff --git a/src/main/java/net/minecraft/world/level/Level.java b/src/main/java/net/minecraft/world/level/Level.java
-index caf2c9799aa5ddbd5caf160e2c8f2e8f0cdaa1f8..9879f9fd804f93faae4419add2c4c64fc6902ba1 100644
+index cb6c6e8c8fe744350a117f38e474ce8f5dd0a43a..1bb7cc9462cab7fbd09b944662711ae5bc5cf950 100644
 --- a/src/main/java/net/minecraft/world/level/Level.java
 +++ b/src/main/java/net/minecraft/world/level/Level.java
 @@ -154,7 +154,7 @@ public abstract class Level implements LevelAccessor, AutoCloseable {

patches/server/0456-Fix-Player-spawnParticle-x-y-z-precision-loss.patch

@@ -5,7 +5,7 @@ Subject: [PATCH] Fix Player spawnParticle x/y/z precision loss
 
 
 diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java
-index 6e9fc623f5a56753e2c78c3ff63c6f4de7cbcccb..ec4ebbdde676806c4b2348408a8004dd66cbc44b 100644
+index 16d1338df730fd66c079b66117cbef91786f2146..f9188664f868c0c55c92c0ec7ca43204d267b91e 100644
 --- a/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java
 +++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java
 @@ -2619,7 +2619,7 @@ public class CraftPlayer extends CraftHumanEntity implements Player {

patches/server/0457-Add-LivingEntity-clearActiveItem.patch

@@ -5,7 +5,7 @@ Subject: [PATCH] Add LivingEntity#clearActiveItem
 
 
 diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftLivingEntity.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftLivingEntity.java
-index bf581842476b8f554987b452c291a55a1dfc92c5..e71f71988790af1a09f65d73dd081490002b821c 100644
+index e07553c3ee28a2510c46a8188c8ce507f2567c80..aac0fb198fb912dc59dc56f449e586839600fa13 100644
 --- a/src/main/java/org/bukkit/craftbukkit/entity/CraftLivingEntity.java
 +++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftLivingEntity.java
 @@ -916,6 +916,13 @@ public class CraftLivingEntity extends CraftEntity implements LivingEntity {

patches/server/0461-Climbing-should-not-bypass-cramming-gamerule.patch

@@ -5,7 +5,7 @@ Subject: [PATCH] Climbing should not bypass cramming gamerule
 
 
 diff --git a/src/main/java/net/minecraft/world/entity/Entity.java b/src/main/java/net/minecraft/world/entity/Entity.java
-index 2b962ef7f167cc3ee17d26b994b6ecc2916f6242..a0c4f6edc87d653bcbe23621bfcf9fbbd20b013d 100644
+index f33067ea049793d898def3c83bff5b36490f8232..3b9c691973f11b7d4db8fb77d2b02aa0d07ed7b5 100644
 --- a/src/main/java/net/minecraft/world/entity/Entity.java
 +++ b/src/main/java/net/minecraft/world/entity/Entity.java
 @@ -1983,6 +1983,12 @@ public abstract class Entity implements Nameable, EntityAccess, CommandSource, S