security: Add new TPM framework

The TPM framework is separated into two parts:
1) The front end class Tpm provides the interface to KeyChain. The public
   interface of Tpm is read-only.
2) The back end classes represent concrete implementations, such as
   tpm::BackEndFile and tpm::BackEndOsx which may also provide
   implementation-specific management interfaces.

New TPM supports different key id type when generating new key.  The
default type is changed to 64-bit random number.

Change-Id: I41154c2ded4b65fb0bef2f4a0d2c5b77843be05d
Refs: #2948
diff --git a/src/security/tpm/key-handle-mem.hpp b/src/security/tpm/key-handle-mem.hpp
new file mode 100644
index 0000000..006c4ec
--- /dev/null
+++ b/src/security/tpm/key-handle-mem.hpp
@@ -0,0 +1,63 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2013-2016 Regents of the University of California.
+ *
+ * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
+ *
+ * ndn-cxx library is free software: you can redistribute it and/or modify it under the
+ * terms of the GNU Lesser General Public License as published by the Free Software
+ * Foundation, either version 3 of the License, or (at your option) any later version.
+ *
+ * ndn-cxx library 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 Lesser General Public License for more details.
+ *
+ * You should have received copies of the GNU General Public License and GNU Lesser
+ * General Public License along with ndn-cxx, e.g., in COPYING.md file.  If not, see
+ * <http://www.gnu.org/licenses/>.
+ *
+ * See AUTHORS.md for complete list of ndn-cxx authors and contributors.
+ */
+
+#ifndef NDN_SECURITY_TPM_KEY_HANDLE_MEM_HPP
+#define NDN_SECURITY_TPM_KEY_HANDLE_MEM_HPP
+
+#include "key-handle.hpp"
+
+namespace ndn {
+namespace security {
+
+namespace transform {
+class PrivateKey;
+} // namespace transform
+
+namespace tpm {
+
+/**
+ * @brief A TPM key handle that keeps the private key in memory
+ */
+class KeyHandleMem : public KeyHandle
+{
+public:
+  explicit
+  KeyHandleMem(shared_ptr<transform::PrivateKey> key);
+
+private:
+  ConstBufferPtr
+  doSign(DigestAlgorithm digestAlgorithm, const uint8_t* buf, size_t size) const final;
+
+  ConstBufferPtr
+  doDecrypt(const uint8_t* cipherText, size_t cipherTextLen) const final;
+
+  ConstBufferPtr
+  doDerivePublicKey() const final;
+
+private:
+  shared_ptr<transform::PrivateKey> m_key;
+};
+
+} // namespace tpm
+} // namespace security
+} // namespace ndn
+
+#endif // NDN_SECURITY_TPM_KEY_HANDLE_MEM_HPP