papermc/CraftBukkit-Patches/0034-Prevent-handshake-spam-from-invalid-names.patch

From 81f21d28642e50e9fae1f7feadbb2882e7820f40 Mon Sep 17 00:00:00 2001
From: Benjamin James Harrison-Sims <tehrainbowguy@gmail.com>
Date: Sun, 14 Apr 2013 21:19:57 +0500
Subject: [PATCH] Prevent handshake spam from invalid names.


diff --git a/src/main/java/net/minecraft/server/Packet2Handshake.java b/src/main/java/net/minecraft/server/Packet2Handshake.java
index 343af93..26de0b5 100644
--- a/src/main/java/net/minecraft/server/Packet2Handshake.java
+++ b/src/main/java/net/minecraft/server/Packet2Handshake.java
@@ -14,11 +14,13 @@ public class Packet2Handshake extends Packet {
 
     public Packet2Handshake() {}
 
+    public static final java.util.regex.Pattern validName = java.util.regex.Pattern.compile("^[a-zA-Z0-9_-]{2,16}$");
     public void a(DataInputStream datainputstream) throws IOException { // CraftBukkit - throws IOException
         this.a = datainputstream.readByte();
         this.b = a(datainputstream, 16);
         this.c = a(datainputstream, 255);
         this.d = datainputstream.readInt();
+        if(!validName.matcher(this.b).matches()) throw new IOException("Invalid name!"); // Spigot
     }
 
     public void a(DataOutputStream dataoutputstream) throws IOException { // CraftBukkit - throws IOException
-- 
1.8.1.2