I'm wondering how to create a Delphi 32bits program (MyApp.exe) to modify an application (App.EXE) for
which I don't have the source code so that this application ask you a password (and a username optionally) before you can launch it.
In order to be more precise, I've already developed such a password function (Mypasswd) which is available in a DLL (MyLib.DLL). How can I modify App.EXE so that it execute the function Mypasswd from MyLib.DLL and then accept to launch only when the result of the call to MyPasswd is true.
I know that modifying another companies executable is illegal... but I know too that's possible and I'm curious
to learn the tip...
Another way to solve my problem could be to write a program that scans for any given executable, and override the start of it, by intercepting the windows messages... If they enter the correct password, you continue to process the file, if they don't, you stop the application
from running.... The problem with this solution, is that this special pgm must always run in background. How to be sure that is the case and that the user cannot stop this pgm...
Any help or information (a source code example) is welcome.
Thanks in advance for your help