downloadbrowseoldsoft's Oldsofts R0lling Key Challenge

Download r0lling-challenge.zip, 2 kb (password: crackmes.de)
Browse contents of r0lling-challenge.zip

Ok, this is my first Java keyfileme challenge.

It uses so-called rolling key techinque, that next key byte is dependant of previous.

Your job: Make a keyfile generator that makes a valid key. And as a extra task: Analyze how algorithm works.

Difficulty: 3 - Getting harder
Platform: Multiplatform
Language: Java

Published: 29. Aug, 2006
Downloads: 460

Rating

Votes: 4
Crackme is quite nice.

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Solutions

Solution by crp-, published 17. sep, 2006; download (553 kb), password: crackmes.de or browse.

crp- has rated this crackme as awesome.

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Discussion and comments

crp-
12. Sep 2006
homegrown obfuscator?
oldsoft
Author
16. Sep 2006
yes, correct.. It uses homegrown one.
badmojo
16. Sep 2006
Welcome to OldSofts R0lling Key Challenge!
You must make a valid keyfile, to success!
Checking key...
Good Job! You made it!



Nice challenge, thanks! Will write solution if I have time. This one is interesting.
crp-
16. Sep 2006
i suggest anyone who's bored of x86 asm taking a look at this one (without looking at a solution). quite fun :)

ps: i fear i accidently gave this crackme a bad rating. if a moderator could fix this?
oldsoft
Author
16. Sep 2006
I am glad that you like it :)
oldsoft
Author
17. Sep 2006
Nice solution, crp-
Well done :)
elfz
19. Sep 2006
crp-'s rating pushed up.
warsaw
02. Aug 2012
Are you sure this is a homebrewed obfuscator? The structure of the string decryption function is very similar to one in the Burp software suite.
tamaroth
Moderator
05. Aug 2012
Note that at that time (2006) it might have been home-brewed but have since turned into a full grown product. Who knows, maybe oldsoft even made it.
warsaw
30. Oct 2012
According to this, http://www.the-playground.dk/index.php?page=zelix-klassmaster-string-encryption, the string encryption is the exact same as that used by Zelix Klassmaster, a commercial product, (Which dates to before 2006). Is there anyway to report crackmes?
draww
31. Oct 2012
@warsaw: you can contact one of the moderators and explain the situation.

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