security: Add digest calculation support in transformation

Change-Id: I8326c19aff580289b5301687351d81fd74af8a83
Refs: #3009
diff --git a/src/security/security-common.hpp b/src/security/security-common.hpp
index ad3f671..8edb22c 100644
--- a/src/security/security-common.hpp
+++ b/src/security/security-common.hpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /**
- * Copyright (c) 2013-2014 Regents of the University of California.
+ * Copyright (c) 2013-2016 Regents of the University of California.
  *
  * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
  *
@@ -22,40 +22,41 @@
 #ifndef NDN_SECURITY_COMMON_HPP
 #define NDN_SECURITY_COMMON_HPP
 
+#include "../common.hpp"
+
 namespace ndn {
 
-namespace signed_interest{
+namespace signed_interest {
 
-enum {
-  POS_SIG_VALUE = -1,
-  POS_SIG_INFO = -2,
-  POS_RANDOM_VAL = -3,
-  POS_TIMESTAMP = -4,
+const ssize_t POS_SIG_VALUE = -1;
+const ssize_t POS_SIG_INFO = -2;
+const ssize_t POS_RANDOM_VAL = -3;
+const ssize_t POS_TIMESTAMP = -4;
 
-  MIN_LENGTH = 4
-};
+const size_t MIN_LENGTH = 4;
 
 } // namespace signed_interest
 
 enum KeyType {
-  KEY_TYPE_RSA   = 0,
-  KEY_TYPE_ECDSA = 1,
-  // KEY_TYPE_DSA,
-  KEY_TYPE_AES   = 128,
-  // KEY_TYPE_DES,
-  // KEY_TYPE_RC4,
-  // KEY_TYPE_RC2
-  KEY_TYPE_NULL  = 255
+  KEY_TYPE_NONE  = 0,
+  /// @deprecated use KEY_TYPE_NONE
+  KEY_TYPE_NULL = KEY_TYPE_NONE,
+
+  KEY_TYPE_RSA   = 1,
+  KEY_TYPE_ECDSA = 2,
+  KEY_TYPE_AES   = 128
 };
 
 enum KeyClass {
+  KEY_CLASS_NONE,
   KEY_CLASS_PUBLIC,
   KEY_CLASS_PRIVATE,
   KEY_CLASS_SYMMETRIC
 };
 
 enum DigestAlgorithm {
-  DIGEST_ALGORITHM_SHA256
+  DIGEST_ALGORITHM_NONE = 0,
+  DIGEST_ALGORITHM_SHA256 = 1
 };
 
 enum EncryptMode {
@@ -65,10 +66,11 @@
 };
 
 enum AclType {
+  ACL_TYPE_NONE,
   ACL_TYPE_PUBLIC,
   ACL_TYPE_PRIVATE
 };
 
 } // namespace ndn
 
-#endif
+#endif // NDN_SECURITY_COMMON_HPP