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Code Book Cipher Cracked
AssFace writes: "The Code Book challenge -- I believe 10,000 pounds was the reward for it, and it consisted of 10 stages of increasing difficulty that mimicked the evolution of cryptography throughout history -- was cracked and there is a fantasitc description all at http://www.simonsingh.com/. Goodbye Simon Singh." It's a cool read, too -- both Singh's own writeup, and that of the Swedes who broke the cipher. Congratulations to the winners.
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Does anyone actually have a Java program designed to control air traffic, or for the operation of a nuclear facility?
...anyone here knows what's the status on the Merlin Challenge book? Has it been solved yet?
Tongue-tied and twisted, just an earth-bound misfit, I
Learning to fly, Pink Floyd.
PERIOD. Things such as this just promote the interest in cryptography and interest and knowledge in cryptography is feared and hated by governments and content industries such as those that make up the MPAA. Folks, you're not allowed to experiment with cryptography because it may give you the knowledge to crack technological protection measures which is prohibited under the Digital Millenium Copyright Act. Face it, cryptographic knowledge is a forbidden fruit. Unless you are a government employee working on a government project or a major (large corporation) copyright holder trying to protect it's assets and to assert control over it's content then you have no business to have any knowledge whatsoever about cryptography. Only criminals need to crack copyrighted material and only criminals need to hide what they say from the government. The government has our best interests at heart... AT ALL TIMES.
I guess because you cant arrest the person who broke it from the Ukraine without a lot of trouble. Bah, if only we could get The Man out of the computer world, then it would be a true match between encryptors and decryptors. Would be amusing to make the Internet a scary place again.
It's there. They used the Fermat Text in latin and did a letter count (as opposed to the word count in Beale Ciphers.) - Read the PDF on Simon's site. RB
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ah honey, we're all resplendent - Bill Mallonee
stage 10 required the factorisation of a 512-bit number. Singh says the authors had access only to 'ordinary' computers but I'd think 99% of people don't have access to a computer with 4Gb of RAM like the winners did. congratulations to them on cracking stage 5 - now that was obscure!
Get the PDF - Stage 5 is in there in detail. It was a bitch indeed...
"Depression is merely anger without enthusiasm." - Anonymous
Perhaps it was, "Hello Slashdot Effect, goodbye Simon Singh"?
The son of a bitch about stage 5 was that technically, it was a cipher of numbers built off of a key text - you use the first letter of each numbered word (for example, 1 2 3 4 5 in this comment would equal Tsoab - To make it worse, sounds like he just used a short text and numbered the letters instead. And it was a LATIN version of the text. (Lots of those were in foreign languages. Ouch)
So it wasn't so much decrypting as finding a key text that fit the numbers. It's modeled off the Beale cyphers, which are three lists of numbers that supposedly point to gold. The second one used the Declaration of Independance as a code text. No one can find the first or third, as I recall.
It's virtually a one time pad if you wrote the key text yourself, and in all other respects, is more a matter of luck in finding the text then skills/techniques used in any of the other ciphers (frequency analysis, familiarity with the cipher) and so forth) - Most groups didn't get this one till much later. Most skipped it for quite a while.
I was looking for some text that might be based in Oxford myself, like a text of Newton's or something. Suck.
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ah honey, we're all resplendent - Bill Mallonee
For those of you who haven't read this book but are interested in cryptography, I can't urge you enough to read it. The challenge at the back is especially enticing. I'm not sure if it will lose its appeal now that the answers are published and known, but for me there was something absolutely special about breaking the codes and knowing that I was one of the few people in the world to have done it.
I solved stages 1 - 6 and 9 (I was on the 2nd team to brute force the Stage 9 DES cipher). Stage 7 was the ADFGVX cipher used in WWI and Stage 8 was the infamouse Enigma cipher used in WWII. For those who haven't had a crack at this, it's certainly worth it. IMO there is nothing quite like revealing a code piece by piece. I was privelaged or lucky enough to decipher some of the hints on the eGroups message board and be one of the first few to solve Stage 5, and the elation from seeing--for the first time--what only a few people have ever seen is nearly indescribable.
In summary, this was a wonderful book and an excellent adventure. Best wishes to the Swedish smarties who actually cracked Stage 10 (they had to pick between brute forcing triple DES or 512-bit RSA) and to everyone else who contributed along the way. It has certainly been an excellent experience!
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Have fun: Join D.N.A. (National Dyslexics Association)
The explanation does not really skip stage 5. The report was written in TeX and converted to dvi, PostScript, PDF and HTML. Some of these conversion come out better than the others. The conversion to HTML is somehow buggy so it missed the fifth stage. I do promise you that we did solve stage 5 even if it almost made us give up. I mean we searched for that keytext for more than six months and tried almost anything else we could possibly think of. /Fredrik Almgren
This is the first time "normal" computer hardware has been used to break a 512-bit RSA key.
The first public break of an RSA key of this size was performed using 224 CPU hours on a Cray C916 whilst the team that cracked the codebook puzzles took just 13 days on a quad-Alpha Compaq beast.
Don't forget, before the export rules were changed around 90%+ of all "secure" SSL transactions on the internet were using 512-bit keys. Scary, huh?
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"Mary had a crypto key, she kept it in escrow, and everything that Mary said, the Feds were sure to know."
What's interesting about this is that they used the cryptography from the book as a form of authentication! Sort of like a digital signature in reverse. If he was the real Simon Singh, he would have already known the plaintext to #10, and could use that to identify himself. And if he weren't, then he would presumably be from a team that had already solved it, so why bother calling them? (Yeah, I know, they might have solved every one but #5, but the same challenge/response works for all the problems, and strengthens the authentication.)
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"Open source is good." - Steve Jobs
"Open source is evil." - Microsoft
If you go to egroups.com, there is a mailing list called "cipherchallange" that was devoted to this book. in the files section they have electronic versions of all the cipher texts as well as a ton of other data in there.- --------
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There are some odd things afoot now, in the Villa Straylight.