PaperMC/CraftBukkit-Patches/0009-Proxy-IP-Filter.patch

From 6c8715e0ffd4ce12e51b1505bab0af4908744c2e Mon Sep 17 00:00:00 2001
From: md_5 <md_5@live.com.au>
Date: Tue, 23 Apr 2013 11:22:07 +1000
Subject: [PATCH] Proxy IP Filter


diff --git a/src/main/java/net/minecraft/server/ThreadLoginVerifier.java b/src/main/java/net/minecraft/server/ThreadLoginVerifier.java
index 0686ba0..1254e63 100644
--- a/src/main/java/net/minecraft/server/ThreadLoginVerifier.java
+++ b/src/main/java/net/minecraft/server/ThreadLoginVerifier.java
@@ -28,6 +28,7 @@ class ThreadLoginVerifier extends Thread {
 
     public void run() {
         try {
+            if (org.spigotmc.SpamHaus.filterIp(pendingConnection)) return; // Spigot
             String s = (new BigInteger(MinecraftEncryption.a(PendingConnection.a(this.pendingConnection), PendingConnection.b(this.pendingConnection).F().getPublic(), PendingConnection.c(this.pendingConnection)))).toString(16);
             URL url = new URL("http://session.minecraft.net/game/checkserver.jsp?user=" + URLEncoder.encode(PendingConnection.d(this.pendingConnection), "UTF-8") + "&serverId=" + URLEncoder.encode(s, "UTF-8"));
             BufferedReader bufferedreader = new BufferedReader(new InputStreamReader(url.openStream()));
diff --git a/src/main/java/org/spigotmc/SpamHaus.java b/src/main/java/org/spigotmc/SpamHaus.java
new file mode 100644
index 0000000..55d8d12
--- /dev/null
+++ b/src/main/java/org/spigotmc/SpamHaus.java
@@ -0,0 +1,44 @@
+package org.spigotmc;
+
+import java.net.InetAddress;
+import net.minecraft.server.PendingConnection;
+
+public class SpamHaus
+{
+
+    private SpamHaus()
+    {
+    }
+
+    public static boolean filterIp(PendingConnection con)
+    {
+        if ( SpigotConfig.preventProxies )
+        {
+            try
+            {
+                InetAddress address = con.getSocket().getInetAddress();
+                String ip = address.getHostAddress();
+
+                if ( !address.isLoopbackAddress() )
+                {
+                    String[] split = ip.split( "\\." );
+                    StringBuilder lookup = new StringBuilder();
+                    for ( int i = split.length - 1; i >= 0; i-- )
+                    {
+                        lookup.append( split[i] );
+                        lookup.append( "." );
+                    }
+                    lookup.append( "xbl.spamhaus.org." );
+                    if ( InetAddress.getByName( lookup.toString() ) != null )
+                    {
+                        con.disconnect( "Your IP address (" + ip + ") is flagged as unsafe by spamhaus.org/xbl" );
+                        return true;
+                    }
+                }
+            } catch ( Exception ex )
+            {
+            }
+        }
+        return false;
+    }
+}
diff --git a/src/main/java/org/spigotmc/SpigotConfig.java b/src/main/java/org/spigotmc/SpigotConfig.java
index 1d915fb..56ac067 100644
--- a/src/main/java/org/spigotmc/SpigotConfig.java
+++ b/src/main/java/org/spigotmc/SpigotConfig.java
@@ -111,4 +111,10 @@ public class SpigotConfig
         config.addDefault( path, def );
         return config.getString( path, config.getString( path ) );
     }
+
+    public static boolean preventProxies;
+    private static void preventProxies()
+    {
+        preventProxies = getBoolean( "settings.prevent-proxies", false );
+    }
 }
-- 
1.8.1.2