DLL Security

[kandukondein]

Hello Gurus.
I want to make my DLL Secured. FOr instance i export several functions
FuncA,FunB,FuncC which is called by the installer and then software is installed.

But however any naive user can use depends.exe on my DLL and find out that exported functions. He inturn can write a application and call those functions.I want to avoid that.

Right now i am using a simple and a dull method for that. My Exported functions take in user name and password. these are hardcoded GUIDs in the installer as well as the DLL. as the functions get called with these userid and passwords they are verified and the desired functionality is achieved. Such any other malicious user cannot guess the GUID and call those functions...

Is there any way to avoid this dull trick..Actually i dont want the malicious user to even know the exported functions at all..

Ideas are really appreciated.

Thanks and Regards
Kandukondein

[VladimirF]

.Actually i dont want the malicious user to even know the exported functions at all..

You could export your functions by ordinal, with no names.

[JohnCz]

I do not think that is going to solve a problem. Procedure address can be retrieve using ordinals.

You can use many utilities to dump exported functions from a dll.
But in order to use any exported function one would have to know what a formal parameter list.

Hi kandukondein,
If security is really an issue I would go for COM component with licensing (IClassFactory2).
When dll is loaded and initialized license information (key or machine based) can be retrieved and if not found dll initialization would fail.