diff --git a/src/security/transform/block-cipher.hpp b/src/security/transform/block-cipher.hpp
index 320e184..ee56682 100644
--- a/src/security/transform/block-cipher.hpp
+++ b/src/security/transform/block-cipher.hpp
@@ -1,5 +1,5 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
-/**
+/*
  * Copyright (c) 2013-2017 Regents of the University of California.
  *
  * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
@@ -52,6 +52,8 @@
               const uint8_t* key, size_t keyLen,
               const uint8_t* iv, size_t ivLen);
 
+  ~BlockCipher();
+
 private:
   /**
    * @brief Read partial transformation result (if exists) from BIO