Prevent handshake spam from invalid names.

CraftBukkit-Patches/0039-Prevent-handshake-spam-from-invalid-names.patch

@@ -0,0 +1,21 @@
+From f22c9b13df956663f41d000bea443a737624b91c Mon Sep 17 00:00:00 2001
+From: Benjamin James Harrison-Sims <tehrainbowguy@gmail.com>
+Date: Sun, 14 Apr 2013 03:08:51 +0100
+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..920e045 100644
+--- a/src/main/java/net/minecraft/server/Packet2Handshake.java
++++ b/src/main/java/net/minecraft/server/Packet2Handshake.java
+@@ -19,6 +19,7 @@ public class Packet2Handshake extends Packet {
+         this.b = a(datainputstream, 16);
+         this.c = a(datainputstream, 255);
+         this.d = datainputstream.readInt();
++        if(!this.b.matches("^[a-zA-Z0-9_]{3,16}$")){throw new IOException("Invalid name!");}// Spigot
+     }
+ 
+     public void a(DataOutputStream dataoutputstream) throws IOException { // CraftBukkit - throws IOException
+-- 
+1.8.2.1
+