fix memory leak in ccnx-tunnel
diff --git a/src/ccnx-closure.cpp b/src/ccnx-closure.cpp
index a4c378c..528c721 100644
--- a/src/ccnx-closure.cpp
+++ b/src/ccnx-closure.cpp
@@ -44,4 +44,11 @@
   }
 }
 
+Closure *
+Closure::dup() const
+{
+  Closure *closure = new Closure(*this);
+  return closure;
+}
+
 } // Ccnx