Basic command-line tools to export KEK and KDKs

Change-Id: I0975871b6639653e60a2f7ccefaf435147828f33
diff --git a/tools/ndn-nac/main.cpp b/tools/ndn-nac/main.cpp
new file mode 100644
index 0000000..0ebe9ed
--- /dev/null
+++ b/tools/ndn-nac/main.cpp
@@ -0,0 +1,76 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2014-2018, Regents of the University of California
+ *
+ * NAC 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.
+ *
+ * NAC 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 NAC library authors and contributors.
+ */
+
+#include "ndn-nac.hpp"
+#include "version.hpp"
+
+#include <boost/exception/get_error_info.hpp>
+#include <ndn-cxx/util/logger.hpp>
+
+NDN_LOG_INIT(nac.Cmd);
+
+std::string nac_helper = R"STR(
+  help         Show all commands
+  version      Show version and exit
+  dump-kek     Dump KEK
+  add-member   Create KDK for the member
+)STR";
+
+int
+main(int argc, char** argv)
+{
+  if (argc < 2) {
+    std::cerr << nac_helper << std::endl;
+    return 1;
+  }
+
+  using namespace ndn::nac;
+
+  std::string command(argv[1]);
+  try {
+    if (command == "help")              { std::cout << nac_helper << std::endl; }
+    else if (command == "version")      { std::cout << NDN_NAC_VERSION_BUILD_STRING << std::endl; }
+    else if (command == "dump-kek")     { return nac_dump_kek(argc - 1, argv + 1); }
+    else if (command == "add-member")   { return nac_add_member(argc - 1, argv + 1); }
+    else {
+      std::cerr << nac_helper << std::endl;
+      return 1;
+    }
+  }
+  catch (const std::exception& e) {
+
+    std::cerr << "ERROR: " << e.what();
+
+    std::ostringstream extendedError;
+    const char* const* file = boost::get_error_info<boost::throw_file>(e);
+    const int* line = boost::get_error_info<boost::throw_line>(e);
+    const char* const* func = boost::get_error_info<boost::throw_function>(e);
+    if (file && line) {
+      extendedError << " [from " << *file << ":" << *line;
+      if (func) {
+        extendedError << " in " << *func;
+      }
+      extendedError << "]";
+    }
+    NDN_LOG_ERROR(e.what() << extendedError.str());
+    return 1;
+  }
+
+  return 0;
+}