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Easy Encryption API cracker (proof of concept)

Started by immibis, 11 March 2013 - 09:57 PM
immibis #1
Posted 11 March 2013 - 10:57 PM
This program attempts to decrypt English text encrypted by Malte's Easy Encryption API without knowing the key, only the key length.

The message must be much larger than the key (at least 20 times, maybe more) and must be English text - this probably won't work on Lua code, unless you change rateText. The running time is approximately O(size of key * size of message).

Download

Screenshots at different key lengths:













(the last ones show why I said the message must be many times the key length)
theoriginalbit #2
Posted 11 March 2013 - 10:59 PM
Haha nice work immibis! :P/>
superaxander #3
Posted 12 March 2013 - 01:18 AM
That looks very funny
immibis #4
Posted 12 March 2013 - 01:42 AM
Can't edit on my phone - but if you're referring to the last screenshots, that's why I said the message length must be many times the key length.
Lyqyd #5
Posted 12 March 2013 - 08:25 AM
This is not malicious. Not because the encryption API it targets isn't in wide use, but because all it attempts to do is decrypt a string of cyphertext. If it had other "features" like rednet sniffing, etc. then the tool would start running afoul of the malicious code rule.
tesla1889 #6
Posted 12 March 2013 - 08:32 AM
could the full CC definition of malicious code be posted somewhere please?
PixelToast #7
Posted 12 March 2013 - 08:41 AM
now break mine!
http://www.computercraft.info/forums2/index.php?/topic/4030-working-password-based-encryption
tesla1889 #8
Posted 12 March 2013 - 08:44 AM
i dont suppose rainbow tables would be much use in CC
bjornir90 #9
Posted 12 March 2013 - 08:48 AM
Looks funny :)/>
Malte #10
Posted 13 March 2013 - 07:41 AM
Wow… Time to make Version 2! :)/>