papermc/Spigot-Server-Patches/0326-Limit-Client-Sign-length-more.patch
Shane Freeder 7ef05fbd8a Do not perform neighbour updates when using debug stick (Fixes #2134)
CB blindly drops any update flags when recording block modifications,
this causes the debug stick to blindly update neighbouring blocks on usage
in order to control this, we will special case this item, however, this
ideally should be fixed by recording the actual update flags used,
but will induce ABI breaks...

This patch also maintains the behavior of the BlockPlaceEvent, this
behavior will NOT be guaranteed in the future, however.
2020-12-22 22:45:10 +00:00

54 lines
3.2 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Wed, 27 Feb 2019 22:18:40 -0500
Subject: [PATCH] Limit Client Sign length more
modified clients can send more data from the client
to the server and it would get stored on the sign as sent.
Mojang has a limit of 384 which is much higher than reasonable.
the client can barely render around 16 characters as-is, but formatting
codes can get it to be more than 16 actual length.
Set a limit of 80 which should give an average of 16 characters 2
sets of legacy formatting codes which should be plenty for all uses.
This does not strip any existing data from the NBT as plugins
may use this for storing data out of the rendered area.
it only impacts data sent from the client.
Set -DPaper.maxSignLength=XX to change limit or -1 to disable
diff --git a/src/main/java/net/minecraft/server/PlayerConnection.java b/src/main/java/net/minecraft/server/PlayerConnection.java
index d5397f670f3908a39b2a398ab59f7743c48bef47..af80dcddc4f65acc916b5b12bb7f9fb2effd3b90 100644
--- a/src/main/java/net/minecraft/server/PlayerConnection.java
+++ b/src/main/java/net/minecraft/server/PlayerConnection.java
@@ -108,6 +108,7 @@ public class PlayerConnection implements PacketListenerPlayIn {
private int E;
private int receivedMovePackets;
private int processedMovePackets;
+ private static final int MAX_SIGN_LINE_LENGTH = Integer.getInteger("Paper.maxSignLength", 80);
private static final long KEEPALIVE_LIMIT = Long.getLong("paper.playerconnection.keepalive", 30) * 1000; // Paper - provide property to set keepalive limit
public PlayerConnection(MinecraftServer minecraftserver, NetworkManager networkmanager, EntityPlayer entityplayer) {
@@ -2706,7 +2707,17 @@ public class PlayerConnection implements PacketListenerPlayIn {
String[] lines = new String[4];
for (int i = 0; i < list.size(); ++i) {
- lines[i] = SharedConstants.filterAllowedChatCharacters(list.get(i)); // Paper - Replaced with anvil color stripping method to stop exploits that allow colored signs to be created.
+ // Paper start - cap line length - modified clients can send longer data than normal
+ String currentLine = list.get(i);
+ if (MAX_SIGN_LINE_LENGTH > 0 && currentLine.length() > MAX_SIGN_LINE_LENGTH) {
+ // This handles multibyte characters as 1
+ int offset = currentLine.codePoints().limit(MAX_SIGN_LINE_LENGTH).map(Character::charCount).sum();
+ if (offset < currentLine.length()) {
+ list.set(i, currentLine = currentLine.substring(0, offset));
+ }
+ }
+ // Paper end
+ lines[i] = SharedConstants.filterAllowedChatCharacters(currentLine); // Paper - Replaced with anvil color stripping method to stop exploits that allow colored signs to be created.
}
SignChangeEvent event = new SignChangeEvent((org.bukkit.craftbukkit.block.CraftBlock) player.getWorld().getBlockAt(x, y, z), this.server.getPlayer(this.player), lines);
this.server.getPluginManager().callEvent(event);