Saturday, September 08 2007 @ 09:48 AM CEST Contributed by: ColdT Views: 5573
This essay consists of a CRC tutorial and a way of how to reverse it. Many
Coders/Reversers don't know exactly how CRC works and almost no one knows how to
reverse it, while this knowledge could be very usefull.
First the tutorial will
learn you how to calculate CRC in general, you can use it as data/code
protection. Second, the reverse part will learn you (mainly) how to reverse
CRC-32, you can use this to break certain CRC protections in programs or over
programs (like anti-virus).
There seem to be utilities who can 'correct' CRCs
for you, but I doubt they also explain what they're doing.
I'd like to warn you, since there is quite some math used in this essay. This
wont harm anyone, and will be well understood by the avarage Reverser or Coder.
Why? Well. If you dont know why math is used in CRC, I suggest that you click
that button with a X at the top-right of this screen. So I assume the reader has knowledge of binair arithmetic.
Saturday, September 08 2007 @ 09:06 AM CEST Contributed by: viruset56 Views: 1654
Level : 1/10 OS : windows Language : C
- Add 2 new sub menu-items under the menu-item 'File'.
- Call one of them 'Info'.
- The other one 'hide'.
- Add a seperator between 'hide' and 'exit'.
- Make the 'Info' button display an alert(OK button) with the text "Net Force Reverse Engineering Challenge".
- Disable the 'hide' button so you can't click it anymore and it's gray.
- Change the text "Hello World!" into "Reverse Engineering is cool!".
- Write a full tutorial on how you did it.
- Patch hello.exe and make everything work.