Coding contests >> Human breakable encryption
Posted by eosp on 10:16:00 09-30-2003
You can never beat my encryption. 3 encoding methods in one, and it still can be en/decrypted w/o a PC.

Winner gets bragging rights.

2fnegc/J/ensq is the encoded form of "Hello."

3ohd/K/opr is too.

Write a piece of C code that can translate any scanf'ed message to and from my code, in both two and three form.

Good luck. [addsig]
Posted by cowsarenotevil on 10:33:00 09-30-2003
If you ever plan on using this comercially, it'd be a good idea to make it not take up more space than the original

EDIT: Also, it's impossible to write a program that decrypts it, there are hundreds of possibilities. It'd be a guessing game.

[ This Message was edited by: cowsarenotevil on 2003-09-30 10:34 ]
Posted by Neu[Mann] on 11:48:00 09-30-2003
If you want me to break you encryption, I'll need more samples. I could make up a way to obtain Hello from your strings that could be horribly wrong unless I verify with another string.
Posted by dxprog on 00:01:00 10-01-2003
Yes, please. GIve another string. I'm so close to cracking this thing that it's driving me nuts!! Also, are the quotes and period in "Hello." included in the encrypted string? Thanks. [addsig]
Posted by eosp on 10:02:00 10-01-2003
I'm nice, so here you go. These two mean "OSDEV ROCKS".

2UFEXGMTHGGUP/Q/MFGXDQQM

3vfcuhrv/r/lgycrn

By the way its longer because of the slashes marking the middle and because of the fake letters.

Hints:
The encoding methods are rearranging the letters, changing the letters, and adding fake letters. [addsig]
Posted by eosp on 10:04:00 10-01-2003
DXPROG - the quotes and period are not in the code, and it isn't case sensitive. [addsig]
Posted by dxprog on 10:21:00 10-01-2003
Quote:
On 2003-10-01 10:02, eosp wrote:
Hints:
The encoding methods are rearranging the letters, changing the letters, and adding fake letters.



I'd already figured that out [addsig]
Posted by eosp on 10:34:00 10-01-2003
If you can solve this without a computer, it is easily solved with one.

By the way - even I don't have a code yet. I just have the code to work it with.

Crack the code first. Then code it. [addsig]
Posted by dxprog on 22:55:00 10-01-2003
I've figured out how to decrypt 'em without a computer, and I have some VB code to do the job. I'll port the code over to C today BTW, are the extra letters random? If so I guess I 3l/Z/nq

_________________
May the Force (of programming) be with you.

[ This Message was edited by: dxprog on 2003-10-01 23:00 ]
Posted by eosp on 09:54:00 10-02-2003
2dzhqfrbfougktchwccaimqh/E/ypmtevfnkvkpdzetbi, and yes the letters are random.

Numbers are spelled out and spaces are taken out. This is one code where 0 is actually coded. [addsig]
Posted by dxprog on 10:25:00 10-02-2003
I have to admit, I haven't figured out all the secrets to the 2 version of encrypting. The way I did it dxprog came out xdrpog, so I still have some work ahead of me 3mlailvvqgo\M\ibqm`lebpq
[addsig]
Posted by eosp on 10:43:00 10-02-2003
Punctuation is eliminated too. By the way, the fake is every 3hwi/R/kpu letter with 2 code, and the letters are shifted like 3, but only two instead of 3.

That didn't code right either. [addsig]
Posted by dxprog on 12:27:00 10-02-2003
Okay, then I was right. I figured that the 3uen/x/qlph determined the 3wvki/r/jih of the fake (which proved true in my programming examples. So, you could actually do beyond 3 if you wanted BTW, I'll be submitting my code in C#.NET. I'm having trouble with string functions (see my post in the C\C++ forum)

_________________
May the Force (of programming) be with you.

[ This Message was edited by: dxprog on 2003-10-02 12:31 ]
Posted by eosp on 10:15:00 10-03-2003
I can kinda read vb, so its ok.

Also, your code is decoding bad for sum reason. Can you send me how you are encoding?
_________________
C is the best programming language. Semicolon.

[ This Message was edited by: eosp on 2003-10-03 10:18 ]
Posted by dxprog on 10:38:00 10-03-2003
I'll e-mail you (don't want to let everyone else know how to decode it ) [addsig]
Posted by welshbard482 on 22:00:00 10-03-2003
You guys are like bletchley park... I have a few codes up my sleeve too; I may post a few once I've really got'em down
Posted by eosp on 12:47:00 10-05-2003
Who gives up? [addsig]