MR.HAANDI's Intersection #1
| Download Inversection_#1.zip, 138 kb (password: crackmes.de) Browse contents of Inversection_#1.zip Your task today is: Find out what the hell is going on!
Difficulty: 8 - *VERY VERY* hard | RatingWaiting for at least 3 votes View profile of MR.HAANDI » |
Solutions
Solution by andrewl.us, published 17. mar, 2010; download (478 kb), password: crackmes.de or browse.
andrewl.us has not rated this crackme yet.
Discussion and comments
| HMX0101 28. Sep 2007 | lol, text in serial box are a valid serial =) that's a help? :) |
|---|---|
| IMPosTOR 28. Sep 2007 | algorithm detective md5 sha-1 rijndael :-? |
| MR.HAANDI Author 28. Sep 2007 | "text in serial box are a valid serial =)" yes, that is one of some points I built in as help. *Still the serial is also there to confuse ;)* "algorithm detective" md5,sha-1,rijndael what "algorithm detective" do you use? PEiD only shows MD5, which is correct. btw, partially this crackme is based on that: http://uncyclopedia.org/wiki/MD5 |
| human_thought 30. Sep 2007 | i hate to say that but you can't really expect someone to really get a grip on your crackme with such long validation routine,unless you're a very well-known scene reverser :p And if you have used a proven math algo that simply cannot be reversed,what's the point in analysing this one? |
| lilcw 30. Sep 2007 | md5 can be reversed but for sure you wont get valid text |
| MR.HAANDI Author 30. Sep 2007 | @human_thought: well, firstly, the validation routine is long, but you soon will notice recurrent structures and label them appropriately. secondly, it is based on a math problem, that if you create a valid solver can be solved in less than 20 seconds. thirdly, it is level 8 - nobody should expect a piece of cake, but if you knew the real checking equation you would laugh ;) |
| sd333221 30. Sep 2007 | Wow, the algo is so huge! Mr.Haandi you got the longest d... :-) |
| MR.HAANDI Author 01. Oct 2007 | @sd333221: I do not exactly know what you intention is by asserting this, but I shall take this as a compliment for my coding effort. |
| Shism 02. Oct 2007 | hes just making fun of you... |
| human_thought 03. Oct 2007 | btw a real difficult crackme's validation routine is pretty small most times :p |
| Shism 04. Oct 2007 | Mr.Haandi is very knowledgeable and I respect his work. A small or long routine this is a hard one... |
| sd333221 06. Oct 2007 | "hes just making fun of you..." No that is not right. It's just that it is nearly impossible to gen this, if you have a real life, because it is very obfuscated, and it takes ages to deobfuscate that algorithm. In "real life" i would patch this, because it would fasten up the registration process |
| sd333221 06. Oct 2007 | Furthermore the arithmetics Library you used makes it very hard to understand it, since you don't know what the calls do... You have to take a deep deep look if you want to solve it. |
| MR.HAANDI Author 07. Oct 2007 | Well, the algorithm itself is not obfuscated and if you'd take a look at the sources - they are pure C++ and very clean. The only thing is: I use expressions like A=(B+C)*(D+E) with overloaded operators, that's why the necessary temporary values are created and copied automatically by the compiler. Additionaly, I've just built in some inline expansion structures, that's why the result appears longer than it is - you have to identify recurrent structures yourself (howev, if this one won't be solved for a longer time, I will remove the inline expansion thing). "Furthermore[,] the arithmetics Library" I use is a open source one, and if you know which compiler I use (it is obvious) you can generate files which identify all the instructions and label them for you; the rest is some math and I think one should have seen elliptic curve crypto in action in order to understand what is going on ;) |
| KoЯn Rulz 18. Dec 2007 | i can patch it and make it self generate but i have not been able to find a valid code |
| Shism 19. Dec 2007 | Where's jb, when you need him to solve something !? |
| divinomas 15. May 2008 | "Intersection" ,as a wired name for a crackme,contains the solution for itself.I think it would be easier to figure out the weakness after knowing which coordinate system for elliptic curve used in this crackme.If I had time I would write a keygen and tutorial,but I think the title itself is sufficient for some smart guys to make it yourself. |
| alex_ls 18. Mar 2010 | It's a very impressive work, andrewl.us. Don't even imagine how you could do this! It's time to learn mathematics :) |
| andrewl.us Moderator 18. Mar 2010 | thanks, but anyone can do it just start at http://www.certicom.com/index.php/ecc-tutorial probably best entry ECC crackme is happytown#26 it's so easy to feel hopeless with all the info out there, but you need an understanding of only a tiny fraction of it (mainly the group behavior) to own up some crackmes |
You may leave your comment, thoughts and discuss this crackme with other reversers here.
Acting childish will not be tolerated.
HTML and such will be left as-is, so don't try.