Added key-chain.cpp
diff --git a/ndn-cpp/key-chain.hpp b/ndn-cpp/key-chain.hpp
new file mode 100644
index 0000000..cef43e1
--- /dev/null
+++ b/ndn-cpp/key-chain.hpp
@@ -0,0 +1,25 @@
+/**
+ * @author: Jeff Thompson
+ * See COPYING for copyright and distribution information.
+ */
+
+#ifndef NDN_KEY_CHAIN_HPP
+#define	NDN_KEY_CHAIN_HPP
+
+#include "data.hpp";
+
+namespace ndn {
+
+class KeyChain {
+public:
+  /**
+   * In data, set the signed info key to the default public key and set the signature using the default private key.
+   * @param data The Data object to sign and set the signature.
+   */
+  static void defaultSign(Data &data);
+
+};
+
+}
+
+#endif