Temporarily comment out openssl code
diff --git a/ndn-cpp/key-chain.cpp b/ndn-cpp/key-chain.cpp
index 003a4a8..d195b6f 100644
--- a/ndn-cpp/key-chain.cpp
+++ b/ndn-cpp/key-chain.cpp
@@ -25,6 +25,7 @@
 0x00, 01  
 };
 
+#if 0
 /**
  * Set digest to the sha-256 digest of data
  * @param data Pointer to the input byte array.
@@ -83,6 +84,6 @@
   
   data.getSignature().setSignature(signature, signatureLength);
 }
-
+#endif
 
 }