Moving RBeEF to trunk

git-svn-id: https://beef.googlecode.com/svn/trunk@503 b87d56ec-f9c0-11de-8c8a-61c5e9addfc9

lib/patches/webrick/httpservlet/filehandler.rb

@@ -0,0 +1,32 @@
+# The following file contains patches for WEBrick.
+
+module WEBrick
+module HTTPServlet
+
+  class FileHandler
+    
+    # prevent directory traversal attacks
+    def prevent_directory_traversal(req, res)
+      raise WEBrick::HTTPStatus::BadRequest, "null character in path" if has_null?(req.path_info)
+
+      if trailing_pathsep?(req.path_info)
+        expanded = File.expand_path(req.path_info + "x")
+        expanded.chop!  # remove trailing "x"
+      else
+        expanded = File.expand_path(req.path_info)
+      end
+      req.path_info = expanded
+    end
+    
+    # checks if a string contains null characters
+    def has_null? (str)
+      str.split(//).each {|c| 
+        return true if c.eql?("\000")
+      }
+      false
+    end
+    
+  end
+  
+end
+end