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Help Break Original Enigma Messages

Posted by ryuzaki0 on from the whirr-click dept.

Stereo writes "The Enigma Machine was cracked in Poland in 1932, but three messages remain unbroken, despite having been intercepted in the North Atlantic in 1942. The M4 Project, named after the four rotor Enigma M4 used for encryption, is a distributed computing effort to break them. One message has already been deciphered successfully!"

17 of 272 comments (clear)

  1. Error by c0dedude · · Score: 3, Interesting

    Are they sure they're not just bad data? Wouldn't it be a good idea to send crap through the lines every so often to throw people off the trail?

    --
    Since when has this country used intellectual elite as a pejorative term?
    1. Re:Error by Anonymous Coward · · Score: 5, Interesting
      One of the main reasons the Enigma crypts were breakable with 1940's technology is that the Germans did _not_ do useful things like that. They re-used keys, left cribs in the messages, etc.

      Basically, they put too much faith in the encryption technology, and didn't put enough effort into securing the rest of the process. It's not unusual, many of today's systems have similar issues.

      The comments in Bruce Schneier's blog list some more things that went wrong in the Enigma process.

    2. Re:Error by massivefoot · · Score: 2, Interesting

      The Germans were over-confident to the point of incompetence with their encryption. The British certainly didn't attempt to change this, and ULTRA was only declassified in 1974, and it's likely as not that the Germans still thought their ciphers invincible at the end of the war.

    3. Re:Error by swillden · · Score: 4, Interesting

      Since the crib relied on the Enigma's inability to encode a letter to itself, the received message must have consisted entirely of the letter L.

      To be precise, the message was slightly more likely to have consisted entirely of the letter L. There's no mathematical guarantee that it would contain all Ls, but a sufficiently long ciphertext message with no Ls in the output would've indicated that, with high probability, there were an unusually large number of Ls in the input. Without knowing the actual story, I'd guess that the message probably wasn't all that long, and the math would probably predict only a few more Ls than normal... but that was enough of a hint that when combined with a knowledge of human behavior gave the cryptanalysts reason to assume it was all Ls and see if they could find key settings that would produce the ciphertext from that input.

      Even at the height of Bletchley Park's codebreaking efficiency, nearly every day's break came down to some clever guess of that sort... "What if we tried this?". I imagine the "all Ls" scenario was one of the easier guesses. In order to make it more certain, the codebreakers even asked the front-line forces to do apparently bizarre things, just so they'd have a keyword they could look for in the subsequent reports.

      Amazing stuff...

      --
      Note to ACs: I usually delete AC replies without reading them. If you want to talk to me, log in.
  2. Build your own Enigma Machine by Derling+Whirvish · · Score: 4, Interesting

    Here's a site where you can order a parts kit to build you own Enigma Machine.

  3. Java Enigma Simulator by Derling+Whirvish · · Score: 4, Interesting

    Here's a Java Enigma Simulator.

  4. Wasn't the enigma cracked? by chanrobi · · Score: 2, Interesting

    Why are there still these 3 messages that are unbroken? None of TFA seems to talk about this. Even though it is interesting to note that it's estimated to take 1-10 days of 100 celerons 24/7 to crack a ciphertext of 180 letters long. And that's with computers that are 60 years ahead of the technology that the enigma was made from.

    1. Re:Wasn't the enigma cracked? by ZigiSamblak · · Score: 3, Interesting

      If it wasn't for the Enigma machine it is unlikely computers would be as advanced as they are today since cracking the enigma code was THE reason computer development really got started with the Mark I in WWII.

    2. Re:Wasn't the enigma cracked? by RedWizzard · · Score: 2, Interesting
      If it wasn't for the Enigma machine it is unlikely computers would be as advanced as they are today since cracking the enigma code was THE reason computer development really got started with the Mark I in WWII.
      This is just not true. Enigma was broken using "bombes" which were not computers by any reasonable definition of the term. A bombe was simply an electromechanical device that tested each possible rotor setting. Colossus, OTOH, considered by some to be the first programmable digital computer, was developed at Bletchley to break the Lorenz ciphers. So if you want to credit Nazi ciphers with advancing the state of computing, that's the one to choose. However Colossus was destroyed at the end of the war and no information about it was made public until the late 1970's. So it's hard to claim it had much impact on the development of the computer (this is why ENIAC was considered to be the first computer for so long).

      The fact is that the ground work for the modern digital computer was laid before the war by Turing and others. The work that was done at places like Bletchey during WWII was essentially lost due to the secrecy surrounding such places (which extended decades after the war ended). That work was recreated independently in any case.

  5. OUTGOING by Anonymous Coward · · Score: 0, Interesting

    HELLO WORLD
    42555 42555
    HELLO WORLD
    09214 09214 37240 37240 79854 79854 16149 16149 57728 57728
    91668 91668 06160 06160 54078 54078 86936 86936 45482 45482
    94556 94556 56024 56024 45578 45578 70434 70434 73211 73211
    15708 15708 47553 47553 54103 54103 57436 57436 62440 62440
    09824 09824 27002 27002 95378 95378 91983 91983 39808 39808
    86851 86851 13314 13314 38277 38277 19941 19941 53182 53182
    83117 83117 69904 69904 19904 19904 74653 74653 31668 31668
    72572 72572 75690 75690 85767 85767 12327 12327 05104 05104
    67592 67592 39784 39784 66557 66557 71706 71706 22765 22765
    60094 60094 55947 55947 28823 28823 00718 00718 10778 10778
    K-BYE

  6. Enigma is fairly close to a OTP by jd · · Score: 4, Interesting
    The Enigma code was broken only in the trivial sense that it was possible to brute-force decrypt the messages, once the algorithm, prng and seed value were known. It was not "broken" in the purist sense of the term, in that there is no shorter method of cracking the messages other than by brute-force.


    The full Enigma code is extremely difficult to break. The machine used by Alan Turing (Colossus) was massively parallel and highly optimized for the task - so much so that it is actually able to compute something like ten times as many keys per second as a modern Pentium 4 using the same algorithm. Not bad, for a machine of that era.


    The Enigma suffered from numerous weaknesses - almost all of them operator error. The encryption mechanism itself was damn good and, if used correctly each time, every time, it would have been horribly difficult for the Bletchley Park team to break.


    The one event that turned Enigma transparent was the re-transmission of a message without the cogs being randomized first. Because a machine had already been recovered, Turing knew what the cogs were, just not where they should be in relation to each other. By having the same message sent twice without change and without a prior reset, it was possible to overlay the two messages and thereby infer virtually everything else.


    This only allows you to crack messages which use the same prng for initialization and identical cogs. Since the cogs were designed to be swappable, non-standard configurations would have been possible. These would not have been crackable - and would likely not be crackable today, if non-standard enough. (The number of arrangements you would need to test increases with the factorial of the number of ways the cogs could be designed, as well as the factorial of the number of ways the cogs could be inserted into the machine.)


    The possibility exists that certain units may have used non-standard Enigma codes, but if that is the case, those codes will NOT be broken by this effort. The groups that spirited high-ranking Germans to South America and other "secure" locations must have had a communication system that the Allies had not yet deciphered, as they must have been able to operate over extremely large distances very quickly, making the use of radio a certainty.


    It is also likely that some units within the German military adopted their own "extra secure" practices when using the Enigma system internally. These may or may not be crackable, depending on how paranoid the commanders were.

    --
    It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
    1. Re:Enigma is fairly close to a OTP by AWeishaupt · · Score: 2, Interesting

      Colossus had nothing to do with cryptanalysis of any Engima variant. The Colossus machines were used to help break the more advanced Baudot code teleprinter systems used for communications between German command posts - particularly the system known to the Allies as 'TUNNY'

  7. Enigma is fundamentally flawed. by Convergence · · Score: 5, Interesting
    Enigma has a fatal flaw: No letter could be encyphered to itself. This is an artifact of the 'reflector disc' at the end this means that a known plaintext, or crib, can be ruled out for a particular offset, if any letter of it matches a letter in the cyphertext. This, combined with message statistics, allows for powerful cryptographic techniques to be used. These techniques were unavailable in WW2, but they exploit fundamental weaknesses in the design.

    Of course, in WW2, it was the misuse of enigma that made it particularily easy to break --- It might only take one weather report to learn the daily subkey. Had Enigma been properly used, it would probably have been nearly unbreakable with WW2 era technology.

    1. Re:Enigma is fundamentally flawed. by mlush · · Score: 3, Interesting
      Of course, in WW2, it was the misuse of enigma that made it particularily easy to break --- It might only take one weather report to learn the daily subkey. Had Enigma been properly used, it would probably have been nearly unbreakable with WW2 era technology.

      One tactic they used was 'Gardening' where they sent out bombers to mine a particular sea area, then sit back and wait for standard message reporting the new minefield

  8. Re:Hey knobjockey by Xilman · · Score: 3, Interesting

    The parent poster is correct: a properly used Enigma machine is effectively unbreakable with the technology of the day and, for that matter, the technology of the next few decades too.

    The majority of the users of the Enigma machine were not using it properly and so left cracks for BP to exploit. All this is well documented by people who do know a great deal about cryptographic systems. Some of them worked for BP and have in-depth first hand knowledge of what they write about.

    Even today's technology, that in the open literature anyway, still has real difficulties breaking Naval Enigma without the weaknesses introduced by the German users of the system. Read the site carefully and you will discover that important amounts of key material are already known, thereby greatly reducing the amount of computation required to find the rest of the key. And even with this assistance, approximately a cpu year is needed to break the encryption.

    All this strongly suggests that Naval Enigma isn't a bad cryptosystem and certainly a good one for the day. There have been many much worse ones fielded in recent years.

    Paul

    --
    Lasciate ogne speranza, voi ch'intrate
  9. Questionable Legality by baudbarf · · Score: 4, Interesting

    Doesn't the DMCA make it illegal to make tools for breaking encryption or even to discuss how encryption may be broken? Aren't those among us who are americans all conspiring to break federal law by attempting or discussing the possibility of attempting to break these enigma messages?

    You're all terrorists. Off to Guantanamo with you.

    --
    You can run but you can't hide, except, apparently, along the Afghan-Pakistani border.
  10. Location of the sub in google maps by armyturtle · · Score: 2, Interesting

    I plotted the approximate location of the german sub at the time they transmitted the message & were following the "enemy." (Based on information from the translated original enigma text.) http://maps.google.com/maps?f=q&hl=en&q=51.33+N,+4 1.35+W&ll=51.289406,-41.308594&spn=52.133005,175.7 8125 Kind of neat to look at.

    --
    Wherever you go, there you are. :D