how to protect dll from replacement.

[AbdulMunaf]

Hi,

I have one executable say program.exe which is linked with first.dll.
first.dll contains TestClass. Now if i replace the first.dll with the
dll of same name and same exported function of class TestClass, but
having different implimentation, then the program.exe is executed with
replaced first.dll.

Is there any way to know that the first.dll is replaced or not.

Regards

 

[titancipher]

You could try hashing the DLL (e.g. sha-1), and compiling the hashes
into program.exe. Your program can then hash the first.dll before
loading it. If the hashes differ, it has been replaced. The issue
with doing it this way is if you change first.dll, you have to re-hash
it, and re-link the program.exe.