Purpur/patches/server/0018-Player-invulnerabilities.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: William Blake Galbreath <Blake.Galbreath@GMail.com>
Date: Sat, 2 May 2020 20:55:44 -0500
Subject: [PATCH] Player invulnerabilities


diff --git a/src/main/java/net/minecraft/server/level/ServerPlayer.java b/src/main/java/net/minecraft/server/level/ServerPlayer.java
index 9ab314490b975417e28f129c72077a7198cf4cc7..4dc545c478e24863c8e9c68060af072f748b735e 100644
--- a/src/main/java/net/minecraft/server/level/ServerPlayer.java
+++ b/src/main/java/net/minecraft/server/level/ServerPlayer.java
@@ -271,6 +271,7 @@ public class ServerPlayer extends Player {
     public PlayerNaturallySpawnCreaturesEvent playerNaturallySpawnedEvent; // Paper
     public org.bukkit.event.player.PlayerQuitEvent.QuitReason quitReason = null; // Paper - there are a lot of changes to do if we change all methods leading to the event
     public boolean purpurClient = false; // Purpur
+    public boolean acceptingResourcePack = false; // Purpur
 
     public ServerPlayer(MinecraftServer server, ServerLevel world, GameProfile profile) {
         super(world, world.getSharedSpawnPos(), world.getSharedSpawnAngle(), profile);
@@ -370,6 +371,7 @@ public class ServerPlayer extends Player {
         this.bukkitPickUpLoot = true;
         this.maxHealthCache = this.getMaxHealth();
         this.cachedSingleMobDistanceMap = new com.destroystokyo.paper.util.PooledHashSets.PooledObjectLinkedOpenHashSet<>(this); // Paper
+        this.spawnInvulnerableTime = world.purpurConfig.playerSpawnInvulnerableTicks; // Purpur
     }
 
     // Yes, this doesn't match Vanilla, but it's the best we can do for now.
@@ -1051,6 +1053,12 @@ public class ServerPlayer extends Player {
 
     }
 
+    // Purpur start
+    public boolean isSpawnInvulnerable() {
+        return spawnInvulnerableTime > 0 || frozen;
+    }
+    // Purpur end
+
     @Override
     public boolean hurt(DamageSource source, float amount) {
         if (this.isInvulnerableTo(source)) {
@@ -1058,7 +1066,7 @@ public class ServerPlayer extends Player {
         } else {
             boolean flag = this.server.isDedicatedServer() && this.isPvpAllowed() && "fall".equals(source.msgId);
 
-            if (!flag && this.spawnInvulnerableTime > 0 && source != DamageSource.OUT_OF_WORLD) {
+            if (!flag && isSpawnInvulnerable() && source != DamageSource.OUT_OF_WORLD) { // Purpur
                 return false;
             } else {
                 if (source instanceof EntityDamageSource) {
@@ -1232,6 +1240,7 @@ public class ServerPlayer extends Player {
             }
             // Paper end
 
+            this.spawnInvulnerableTime = worldserver.purpurConfig.playerSpawnInvulnerableTicks; // Purpur
             return this;
         }
     }
@@ -2039,6 +2048,7 @@ public class ServerPlayer extends Player {
     }
 
     public void sendTexturePack(String url, String hash, boolean required, @Nullable Component resourcePackPrompt) {
+        this.acceptingResourcePack = true; // Purpur
         this.connection.send(new ClientboundResourcePackPacket(url, hash, required, resourcePackPrompt));
     }
 
@@ -2585,9 +2595,17 @@ public class ServerPlayer extends Player {
 
     @Override
     public boolean isImmobile() {
-        return super.isImmobile() || (this.connection != null && this.connection.isDisconnected()); // Paper
+        return super.isImmobile() || frozen || (this.connection != null && this.connection.isDisconnected()); // Paper // Purpur
     }
 
+    // Purpur start
+    private boolean frozen = false;
+
+    public void setFrozen(boolean frozen) {
+        this.frozen = frozen;
+    }
+    // Purpur end
+
     @Override
     public Scoreboard getScoreboard() {
         return this.getBukkitEntity().getScoreboard().getHandle();
diff --git a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
index 1c527309483db75d0bade9662280601078895306..0bb020fb67f546ca18f4a6ca08876f30f62c6de9 100644
--- a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
+++ b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
@@ -2095,12 +2095,21 @@ public class ServerGamePacketListenerImpl implements ServerPlayerConnection, Tic
     @Override
     public void handleResourcePackResponse(ServerboundResourcePackPacket packet) {
         PacketUtils.ensureRunningOnSameThread(packet, this, this.player.getLevel());
+        // Purpur start
+        if (player.level.purpurConfig.playerInvulnerableWhileAcceptingResourcePack && !this.player.acceptingResourcePack) {
+            ServerGamePacketListenerImpl.LOGGER.info("Disconnecting {} due to resource pack packet exploitation attempt", this.player.getName());
+            this.disconnect(Component.translatable("multiplayer.texturePrompt.failure.line1"), org.bukkit.event.player.PlayerKickEvent.Cause.RESOURCE_PACK_REJECTION); // "Server resource pack couldn't be applied"
+            return;
+        }
+        // Purpur end
         if (packet.getAction() == ServerboundResourcePackPacket.Action.DECLINED && this.server.isResourcePackRequired()) {
             ServerGamePacketListenerImpl.LOGGER.info("Disconnecting {} due to resource pack rejection", this.player.getGameProfile().getName()); // Paper - Don't print component in resource pack rejection message
             this.disconnect(Component.translatable("multiplayer.requiredTexturePrompt.disconnect"), org.bukkit.event.player.PlayerKickEvent.Cause.RESOURCE_PACK_REJECTION); // Paper - add cause
         }
         // Paper start
         PlayerResourcePackStatusEvent.Status packStatus = PlayerResourcePackStatusEvent.Status.values()[packet.action.ordinal()];
+        if (player.level.purpurConfig.playerInvulnerableWhileAcceptingResourcePack) player.setFrozen(packStatus == PlayerResourcePackStatusEvent.Status.ACCEPTED); // Purpur
+        this.player.acceptingResourcePack = packStatus == PlayerResourcePackStatusEvent.Status.ACCEPTED; // Purpur
         player.getBukkitEntity().setResourcePackStatus(packStatus);
         this.cserver.getPluginManager().callEvent(new PlayerResourcePackStatusEvent(this.getCraftPlayer(), packStatus)); // CraftBukkit
         // Paper end
diff --git a/src/main/java/net/minecraft/server/players/PlayerList.java b/src/main/java/net/minecraft/server/players/PlayerList.java
index e35e1bf28463d1f21f3610a31316e825c737b260..5efee586de46ba9d22cab6cbc1ec5912332c4d2a 100644
--- a/src/main/java/net/minecraft/server/players/PlayerList.java
+++ b/src/main/java/net/minecraft/server/players/PlayerList.java
@@ -1024,6 +1024,8 @@ public abstract class PlayerList {
         }
         // Paper end
 
+        entityplayer1.spawnInvulnerableTime = entityplayer1.level.purpurConfig.playerSpawnInvulnerableTicks; // Purpur
+
         // CraftBukkit end
         return entityplayer1;
     }
diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java
index 09c88f1bb2d8c629350cb21b3801767295396ea0..f61a1326fa943b606de8f75a6b7f95b9e220047a 100644
--- a/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java
+++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java
@@ -3029,5 +3029,20 @@ public class CraftPlayer extends CraftHumanEntity implements Player {
     public void resetIdleTimer() {
         getHandle().resetLastActionTime();
     }
+
+    @Override
+    public boolean isSpawnInvulnerable() {
+        return getHandle().isSpawnInvulnerable();
+    }
+
+    @Override
+    public int getSpawnInvulnerableTicks() {
+        return getHandle().spawnInvulnerableTime;
+    }
+
+    @Override
+    public void setSpawnInvulnerableTicks(int spawnInvulnerableTime) {
+        getHandle().spawnInvulnerableTime = spawnInvulnerableTime;
+    }
     // Purpur end
 }
diff --git a/src/main/java/org/purpurmc/purpur/PurpurWorldConfig.java b/src/main/java/org/purpurmc/purpur/PurpurWorldConfig.java
index 765523911e448bd7f73e3f6cb8d0e78ddecb9f66..fcf58a69e8f3d0e3aa2566ddcdf05554aec979de 100644
--- a/src/main/java/org/purpurmc/purpur/PurpurWorldConfig.java
+++ b/src/main/java/org/purpurmc/purpur/PurpurWorldConfig.java
@@ -98,6 +98,8 @@ public class PurpurWorldConfig {
     public boolean idleTimeoutCountAsSleeping = false;
     public boolean idleTimeoutUpdateTabList = false;
     public boolean idleTimeoutTargetPlayer = true;
+    public int playerSpawnInvulnerableTicks = 60;
+    public boolean playerInvulnerableWhileAcceptingResourcePack = false;
     private void playerSettings() {
         if (PurpurConfig.version < 19) {
             boolean oldVal = getBoolean("gameplay-mechanics.player.idle-timeout.mods-target", idleTimeoutTargetPlayer);
@@ -109,6 +111,8 @@ public class PurpurWorldConfig {
         idleTimeoutCountAsSleeping = getBoolean("gameplay-mechanics.player.idle-timeout.count-as-sleeping", idleTimeoutCountAsSleeping);
         idleTimeoutUpdateTabList = getBoolean("gameplay-mechanics.player.idle-timeout.update-tab-list", idleTimeoutUpdateTabList);
         idleTimeoutTargetPlayer = getBoolean("gameplay-mechanics.player.idle-timeout.mobs-target", idleTimeoutTargetPlayer);
+        playerSpawnInvulnerableTicks = getInt("gameplay-mechanics.player.spawn-invulnerable-ticks", playerSpawnInvulnerableTicks);
+        playerInvulnerableWhileAcceptingResourcePack = getBoolean("gameplay-mechanics.player.invulnerable-while-accepting-resource-pack", playerInvulnerableWhileAcceptingResourcePack);
     }
 
     public boolean babiesAreRidable = true;