From cdac1cc5aaa97d3bda16c9f2682f74560ab9b244 Mon Sep 17 00:00:00 2001
From: Arndt Brenschede <Arndt.Brenschede@web.de>
Date: Wed, 26 May 2021 08:36:52 +0200
Subject: [PATCH] spam heuristics

---
 .../main/java/btools/server/RouteServer.java  | 20 +++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/brouter-server/src/main/java/btools/server/RouteServer.java b/brouter-server/src/main/java/btools/server/RouteServer.java
index 26ccfd3..7125dc8 100644
--- a/brouter-server/src/main/java/btools/server/RouteServer.java
+++ b/brouter-server/src/main/java/btools/server/RouteServer.java
@@ -87,6 +87,7 @@ public class RouteServer extends Thread implements Comparable<RouteServer>
             String agent = null;
             String encodings = null;
             String xff = null; // X-Forwarded-For
+            String referer = null;
 
             // more headers until first empty line
             for(;;)
@@ -120,6 +121,14 @@ public class RouteServer extends Thread implements Comparable<RouteServer>
               {
                 xff = line.substring( "x-forwarded-for: ".length() );
               }
+              if ( line.startsWith( "Referer: " ) )
+              {
+                referer = line.substring( "Referer: ".length() );
+              }
+              if ( line.startsWith( "Referrer: " ) )
+              {
+                referer = line.substring( "Referrer: ".length() );
+              }
             }
             
             InetAddress ip = clientSocket.getInetAddress();
@@ -149,6 +158,17 @@ public class RouteServer extends Thread implements Comparable<RouteServer>
               }
             }
 
+            if ( referer != null && referer.indexOf( "brouter.de/brouter-web" ) >= 0 )
+            {
+              if ( getline.indexOf( "%7C" ) >= 0 && getline.indexOf( "%2C" ) >= 0 )
+              {
+                writeHttpHeader( bw, HTTP_STATUS_FORBIDDEN );
+                bw.write( "Spam? please stop" );
+                bw.flush();
+                return;
+              }
+            }
+
             if ( getline.startsWith("GET /favicon.ico") )
             {
               writeHttpHeader( bw, HTTP_STATUS_NOT_FOUND );