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+--- Thread: Let's have an encryption CHALLENGE! (/thread-1160.html)
Let's have an encryption CHALLENGE! - na_th_an - 07-22-2003
Quote:Quote:Why complicate things, you can't break any decryption without the key no matter what. So an XOR cryption will do fine for most things. And it's small too.Incorrect. I broke the first encryption technique using english language letter frequency.
Now break the code for a JPG image or for a MP3 XOR-encoded.
Let's have an encryption CHALLENGE! - Nexinarus - 07-22-2003
The only way to break encryption, by definition, is by obtaining the key or method of encryption. How to "obtain" the key can greatly vary either by brute force, trial and error, or cutting somebody's toes off, I duno.
Im probly incredibly stupidly wrong but what the hey
/rant.
Let's have an encryption CHALLENGE! - Agamemnus - 07-22-2003
come on people, why do I have to repeat myself. Most encryption techniques fail to produce completely random results. The decrypter can take advantage of that.
An XOR encryption? As in, swap every 1 to a 0 or 0 to a 1? ........
Let's have an encryption CHALLENGE! - Mango - 07-22-2003
Quote:come on people, why do I have to repeat myself. Most encryption techniques fail to produce completely random results. The decrypter can take advantage of that.
An XOR encryption? As in, swap every 1 to a 0 or 0 to a 1? ........
agamamnus: you XOR the file against a "random appearing" data-stream...a data-strean that can be reproduced when needed. Then, irregardless of the contents of the source file, the encrypted file will appear random. This is very different from swapping all 10 and 01.
Cheers.
Let's have an encryption CHALLENGE! - Agamemnus - 07-22-2003
If the file you're xoring with is not random, you cannot expect the encrypted file to be random as well. If you can generate it, it isn't random. If it is completely random, you need to keep secret a really large file that is the same size as the file needed to encrypt it, which makes it useless.
Let's have an encryption CHALLENGE! - Mango - 07-22-2003
Quote:If the file you're xoring with is not random, you cannot expect the encrypted file to be random as well. If you can generate it, it isn't random. If it is completely random, you need to keep secret a really large file that is the same size as the file needed to encrypt it, which makes it useless.
Oh...my mistake...encryption doesn't work. Thanks for the scoop. :roll:
Let's have an encryption CHALLENGE! - Agamemnus - 07-22-2003
it does work, but only layered encryption+password is 100% secure, like AES.
Let's have an encryption CHALLENGE! - oracle - 07-23-2003
Someone XOR encrypt a JPEG and send it to aga, and aga can post the picture up here to prove it.
Let's have an encryption CHALLENGE! - Blitz - 07-23-2003
Ok aga, decrypt this and i'll change my mind about you being a stupid kid with a big mouth. It's xor encryption.
"T???^T?E(G?
?^ L? ?? E!E§"
Let's have an encryption CHALLENGE! - Blitz - 07-23-2003
Here you have it in hex, it thought i'd make it a little simpler for you.
61 13 0E 54 08 1F 4C 18 00 03 08 1C 00 45 21 45 15 0B 54 05 03 02 5E 54 41 1E 1D 10 45 28 47 06 0D 0A 11 5E