security: Add BlockCipher in transformation

Change-Id: I2c09509acd69e7f9270ef8c9b6e5e16ede2a8042
Refs: #3009
diff --git a/src/security/security-common.hpp b/src/security/security-common.hpp
index 15a82bf..8594581 100644
--- a/src/security/security-common.hpp
+++ b/src/security/security-common.hpp
@@ -73,6 +73,14 @@
 std::ostream&
 operator<<(std::ostream& os, BlockCipherAlgorithm algorithm);
 
+enum class CipherOperator {
+  DECRYPT = 0,
+  ENCRYPT = 1
+};
+
+std::ostream&
+operator<<(std::ostream& os, CipherOperator op);
+
 enum class AclType {
   NONE,
   PUBLIC,