add policy checker

Change-Id: I90c50d15b1d9d97832c66ce90e39524729f12a0f
diff --git a/core/policy-checker.hpp b/core/policy-checker.hpp
new file mode 100644
index 0000000..8eea548
--- /dev/null
+++ b/core/policy-checker.hpp
@@ -0,0 +1,76 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2014,  Regents of the University of California
+ *
+ * This file is part of NSL (NDN Signature Logger).
+ * See AUTHORS.md for complete list of NSL authors and contributors.
+ *
+ * NSL 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 3 of the License, or (at your option) any later version.
+ *
+ * NSL 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
+ * NSL, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * See AUTHORS.md for complete list of nsl authors and contributors.
+ */
+
+#ifndef NSL_CORE_POLICY_CHECKER_HPP
+#define NSL_CORE_POLICY_CHECKER_HPP
+
+#include "common.hpp"
+#include "db.hpp"
+#include "util/non-negative-integer.hpp"
+#include "conf/config.hpp"
+#include "conf/rule.hpp"
+#include <ndn-cxx/security/identity-certificate.hpp>
+
+
+namespace nsl {
+
+class PolicyChecker
+{
+public:
+  class Error : public std::runtime_error
+  {
+  public:
+    explicit
+    Error(const std::string& what)
+      : std::runtime_error(what)
+    {
+    }
+  };
+
+public:
+  PolicyChecker();
+
+  void
+  reset();
+
+  void
+  loadPolicy(const conf::ConfigSection& policy);
+
+  bool
+  check(const Timestamp& dataTimestamp, const Data& data,
+        const Timestamp& keyTimestamp, const ndn::IdentityCertificate& cert);
+private:
+
+  void
+  onConfigRule(const conf::ConfigSection& section);
+
+  bool
+  checkRule(const Data& data);
+
+private:
+  typedef std::vector<shared_ptr<conf::Rule>> DataRuleList;
+
+  DataRuleList m_dataRules;
+};
+
+} // namespace nsl
+
+#endif // NSL_CORE_POLICY_CHECKER_HPP