arintel's MineLock I

This is a $300 challenge. Below is brief information. For a full description, please visit http://minelock.blogspot.com

Description:
This is a small Pocket PC program which shows some medusas moving around the screen and eating each other. The original section of code that controls the movement of the medusas has been transformed by MineLock I technique. You will not find plain assembly instructions changing the positions of the medusas. Also, the transformed code will move the medusas correctly only when the Pocket PC is running at its maximum speed or it will freeze the medusas or quit the program otherwise.

Requirements:
The challenge is reconstruct the original code which changes the positions of the medusas and patch the program for it to run correctly with all speeds of the Pocket PC. You must not simply guess and rewrite the code. You must DEDUCE the original code from the executable file. That is, explain clearly how you get the original code by analyzing the executable file only and support your arguments by reference to the assembly code of the program. You can do it in anyway using any tools of your choice.

Usage:
There are an executable file and two license files. For the program to run correctly, rename the corresponding .lic file to MineLock.lic, put it in the root folder, and run the executable file. You can try running the program with a different speed of the Pocket PC or with a wrong license file to see the medusas freezed.

Difficulty: 9 - You can't solve this yourself :)
Platform: Unspecified/other
Language: C/C++

Published: 30. Mar, 2006
Downloads: 675