From 504d3c0529e2014d5a1c469206db3bfd440829a7 Mon Sep 17 00:00:00 2001
From: md_5 <git@md-5.net>
Date: Sat, 20 Aug 2016 11:43:48 +1000
Subject: [PATCH] #1939: Fix server brand; prevent bungee-bungee connections.

---
 .../main/java/net/md_5/bungee/protocol/DefinedPacket.java | 8 ++++++++
 proxy/src/main/java/net/md_5/bungee/ServerConnector.java  | 2 +-
 .../java/net/md_5/bungee/connection/DownstreamBridge.java | 6 +++++-
 3 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/protocol/src/main/java/net/md_5/bungee/protocol/DefinedPacket.java b/protocol/src/main/java/net/md_5/bungee/protocol/DefinedPacket.java
index 9c086869..10e16d79 100644
--- a/protocol/src/main/java/net/md_5/bungee/protocol/DefinedPacket.java
+++ b/protocol/src/main/java/net/md_5/bungee/protocol/DefinedPacket.java
@@ -48,6 +48,14 @@ public abstract class DefinedPacket
         buf.writeBytes( b );
     }
 
+    public static byte[] toArray(ByteBuf buf)
+    {
+        byte[] ret = new byte[ buf.readableBytes() ];
+        buf.readBytes( ret );
+
+        return ret;
+    }
+
     public static byte[] readArray(ByteBuf buf)
     {
         return readArray( buf, buf.readableBytes() );
diff --git a/proxy/src/main/java/net/md_5/bungee/ServerConnector.java b/proxy/src/main/java/net/md_5/bungee/ServerConnector.java
index 977b3def..976636ac 100644
--- a/proxy/src/main/java/net/md_5/bungee/ServerConnector.java
+++ b/proxy/src/main/java/net/md_5/bungee/ServerConnector.java
@@ -199,7 +199,7 @@ public class ServerConnector extends PacketHandler
 
             ByteBuf brand = ByteBufAllocator.DEFAULT.heapBuffer();
             DefinedPacket.writeString( bungee.getName() + " (" + bungee.getVersion() + ")", brand );
-            user.unsafe().sendPacket( new PluginMessage( "MC|Brand", DefinedPacket.readArray( brand ), handshakeHandler.isServerForge() ) );
+            user.unsafe().sendPacket( new PluginMessage( "MC|Brand", DefinedPacket.toArray( brand ), handshakeHandler.isServerForge() ) );
             brand.release();
         } else
         {
diff --git a/proxy/src/main/java/net/md_5/bungee/connection/DownstreamBridge.java b/proxy/src/main/java/net/md_5/bungee/connection/DownstreamBridge.java
index 3daab361..288d6024 100644
--- a/proxy/src/main/java/net/md_5/bungee/connection/DownstreamBridge.java
+++ b/proxy/src/main/java/net/md_5/bungee/connection/DownstreamBridge.java
@@ -1,6 +1,7 @@
 package net.md_5.bungee.connection;
 
 import com.google.common.base.Objects;
+import com.google.common.base.Preconditions;
 import com.google.common.io.ByteArrayDataOutput;
 import com.google.common.io.ByteStreams;
 import java.io.DataInput;
@@ -233,9 +234,12 @@ public class DownstreamBridge extends PacketHandler
             ByteBuf brand = Unpooled.wrappedBuffer( pluginMessage.getData() );
             String serverBrand = DefinedPacket.readString( brand );
             brand.release();
+
+            Preconditions.checkState( !serverBrand.contains( bungee.getName() ), "Cannot connect proxy to itself!" );
+
             brand = ByteBufAllocator.DEFAULT.heapBuffer();
             DefinedPacket.writeString( bungee.getName() + " (" + bungee.getVersion() + ")" + " <- " + serverBrand, brand );
-            pluginMessage.setData( DefinedPacket.readArray( brand ) );
+            pluginMessage.setData( DefinedPacket.toArray( brand ) );
             brand.release();
             // changes in the packet are ignored so we need to send it manually
             con.unsafe().sendPacket( pluginMessage );