use unique_ptr for ElGamalEncryption

Identity.h

@@ -4,6 +4,7 @@
 #include <inttypes.h>
 #include <string.h>
 #include <string>
+#include <memory>
 #include "base64.h"
 #include "ElGamal.h"
 #include "Signature.h"
@@ -219,23 +220,23 @@ namespace data
 	{
 		public:
 
-			RoutingDestination (): m_ElGamalEncryption (nullptr) {};
-			virtual ~RoutingDestination () { delete m_ElGamalEncryption; };
+			RoutingDestination () {};
+			virtual ~RoutingDestination () {};
 			
 			virtual const IdentHash& GetIdentHash () const = 0;
 			virtual const uint8_t * GetEncryptionPublicKey () const = 0;
 			virtual bool IsDestination () const = 0; // for garlic 
 
-			const i2p::crypto::ElGamalEncryption * GetElGamalEncryption () const
+			std::unique_ptr<const i2p::crypto::ElGamalEncryption>& GetElGamalEncryption () const
 			{
 				if (!m_ElGamalEncryption)
-					m_ElGamalEncryption = new i2p::crypto::ElGamalEncryption (GetEncryptionPublicKey ());
+					m_ElGamalEncryption.reset (new i2p::crypto::ElGamalEncryption (GetEncryptionPublicKey ()));
 				return m_ElGamalEncryption;
 			}
 			
 		private:
 
-			mutable i2p::crypto::ElGamalEncryption * m_ElGamalEncryption; // use lazy initialization
+			mutable std::unique_ptr<const i2p::crypto::ElGamalEncryption> m_ElGamalEncryption; // use lazy initialization
 	};	
 
 	class LocalDestination