diff --git a/common/rfb/CSecurityStack.cxx b/common/rfb/CSecurityStack.cxx
new file mode 100644
index 0000000..cfc60fd
--- /dev/null
+++ b/common/rfb/CSecurityStack.cxx
@@ -0,0 +1,65 @@
+/* Copyright (C) 2005 Martin Koegler
+ * Copyright (C) 2010 TigerVNC Team
+ * 
+ * This is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ * 
+ * This software is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this software; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,
+ * USA.
+ */
+
+#include <rfb/CSecurityStack.h>
+
+using namespace rfb;
+
+CSecurityStack::CSecurityStack(int Type, const char*Name, CSecurity* s0,
+			       CSecurity* s1)
+  :name(Name),type(Type)
+{
+  state = 0;
+  state0 = s0;
+  state1 = s1;
+}
+
+CSecurityStack::~CSecurityStack()
+{
+  if (state0)
+    delete state0;
+  if (state1)
+    delete state1;
+}
+
+bool CSecurityStack::processMsg(CConnection* cc)
+{
+  bool res=true;
+  if (state == 0) {
+    if (state0)
+      res = state0->processMsg(cc);
+
+    if (!res)
+      return res;
+
+    state++;
+  }
+
+  if (state == 1) {
+    if(state1)
+      res = state1->processMsg(cc);
+
+    if(!res)
+      return res;
+
+    state++;
+  }
+
+  return res;
+}