security: Adding CertificateCache and CertificateCacheTtl

Change-Id: I473290af29ab590e2539c1873d23f25190f116fb
diff --git a/src/security/certificate-cache.hpp b/src/security/certificate-cache.hpp
new file mode 100644
index 0000000..14c42d1
--- /dev/null
+++ b/src/security/certificate-cache.hpp
@@ -0,0 +1,32 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil -*- */
+/**
+ * Copyright (C) 2013 Regents of the University of California.
+ * @author: Yingdi Yu <yingdi@cs.ucla.edu>
+ * See COPYING for copyright and distribution information.
+ */
+
+#ifndef NDN_CERTIFICATE_CACHE_HPP
+#define NDN_CERTIFICATE_CACHE_HPP
+
+#include "../name.hpp"
+#include "identity-certificate.hpp"
+
+namespace ndn
+{
+
+class CertificateCache
+{
+public:
+  virtual
+  ~CertificateCache() {}
+    
+  virtual void
+  insertCertificate(ptr_lib::shared_ptr<const IdentityCertificate> certificate) = 0;
+
+  virtual ptr_lib::shared_ptr<const IdentityCertificate> 
+  getCertificate(const Name& certificateNameWithoutVersion) = 0;
+};
+
+}//ndn
+
+#endif