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Encryption Security Science

Do-It-Yourself Electronic Enigma Machine 213

Radio Shack Robot writes "The Enigma-E is a DIY Building Kit that enables you to build your own electronic variant of the famous Enigma coding machine that was used by the German army during WWII. It works just like a real Enigma and is compatible with an M3 and M4 Enigma as well as the standard Service Machines. A message encrypted on, say, a real Enigma M4 can be read on the Enigma-E and vice versa."
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Do-It-Yourself Electronic Enigma Machine

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  • by OverlordQ ( 264228 ) on Sunday February 22, 2004 @04:51AM (#8354654) Journal
    Here's my [] Electronic Enigma Machine.
  • RTFA (Score:5, Informative)

    by Safety Cap ( 253500 ) on Sunday February 22, 2004 @04:54AM (#8354670) Homepage Journal
    We've also got a first in the manual: Frode Weierud and Geoff Sullivan, two well respected Enigma researchers,
    have aquired a large number of original German army messages, which have never been published before. Especially for the Enigma-E, they've released some of these messages, complete with the related Enigma settings and decrypts.
  • by Bobdoer ( 727516 ) on Sunday February 22, 2004 @04:55AM (#8354673) Homepage Journal
    This page [] explains Enigma fairly well.
  • applet (Score:5, Informative)

    by batura ( 651273 ) on Sunday February 22, 2004 @04:55AM (#8354679)
    I thought this was kinda cool, so I looked around for a java applet and found one: Its pretty cool. []
  • by OverlordQ ( 264228 ) on Sunday February 22, 2004 @04:56AM (#8354681) Journal
    The Enigma machine was a simple cipher machine. It had several components: a plug board, a light board, a keyboard, a set of rotors, and a reflector (half rotor). The original machine looked a lot like a typewriter.

    The machine has several variable settings that affect the operation of the machine. The user must select three rotors from a set of rotors to be used in the machine. A rotor contains one-to-one mappings of all the letters. Some Enigma machines had more than 3 rotors which just added to the number of possible encryption combinations. The other variable element in the machine is the plug board. The plug board allowed for pairs of letters to be remapped before the encryption process started and after it ended.

    When a key is pressed, an electrical current is sent through the machine. The current first passes through the plug board, then through the three rotors, through the reflector which reverses the current, back through the three rotors, back through the plug board and then the encrypted letter is lit on the display. After the display is lit up, the rotors rotate. The rotors rotate similar to an odometer where the right most rotor must complete one revolution before the middle rotor rotated one position and so on.

    As the current passes through each component in the Enigma machine, the letter gets remapped to another letter. The plug board performed the first remapping. If there is a connection between two letters, the letters are remapped to each other. For example if there is a connection between "A" and "F", "A" would get remapped to "F" and "F" would get remapped to "A". If this isn't a connection for a particular letter, the letter doesn't get remapped. After the plug board, the letters are remapped through the rotors. Each rotor contains one-to-one mappings of letters but since the rotors rotate on each key press, the mappings of the rotors change on every key press. Once the current passes through the rotors, it goes into the reflector. The reflector is very similar to a rotor except that it doesn't rotate so the one-to-one mappings are always the same. The whole encryption process for a single letter contains a minimum of 7 remappings (the current passes through the rotors twice) and a maximum of 9 remappings (if the letter has a connection in the plug board).

    In order to decrypt a message, the receiver must have the encrypted message, and know which rotors were used, the connections on the plug board and the initial settings of the rotors. To decrypt a message, the receiver would set up the machine identically to the way the sender initially had it and would type in the encrypted message. The output of typing in the encrypted message would be the original message. Without the knowledge of the state of the machine when the original message was typed in, it is extremely difficult to decode a message.
  • by Anonymous Coward on Sunday February 22, 2004 @05:35AM (#8354747)
    There is some sort of description [] written by Turing himself
  • by mlush ( 620447 ) on Sunday February 22, 2004 @06:09AM (#8354796)
    Enigma was an interesting development in cryptography because the rotating wheels caused the crypto output to be evenly distributed accross the alphabet. Therefore, it couldn't be solved by the typical letter replacement cypher techniques of assuming the most used letter in the code stands for "E" until proven otherwise, and working from there.

    One of the interesting weaknesses of the Enigma cypher was no letter could be encoded as itself. One part of the cracking process was to look for messages that had a known content (weather reports were a favorate, the Germans were very keen on standard formats in their reports) This could be used to narrow down the number of possible keys

    Source [] A tired German operator has been told to send out dummy messages and he typed only the last letter of the keyboard : ``L''. The British code breaking expert immediately recognized the missing ``L'' in the enciphered message and they got a very big crib.


  • Enigma Books (Score:5, Informative)

    by iplead5th ( 703252 ) on Sunday February 22, 2004 @06:09AM (#8354797) Homepage
    I recomend to anyone who would like this Enigma machine thingy--or anyone interested in learning more about cryptography--to go out and get The Code Book by Simon Singh. Amazon [] It explains in a fair amount of detail how cryptography works, but also the history behind it. I remember it having a chapter or two on the Enigma Machine and also how they broke it. It was a very interesting read, but it isn't a techinical book, more for reader enjoyment and probably at the level of anyone who wants to build this kit. There are some puzzles on the back that are pretty hard to solve, although it would be cool to use this enigma machine to solve the enigma code in the back--you would still have to figure out all the settings, so it would be impossible and not help at all, but imagine the cool factor. There are a lot of other great books on cryptography but this is the only one I have read yet so I feel its the only one I'm allowed to recomend to you guys.
  • by urbaneassault ( 233554 ) on Sunday February 22, 2004 @06:11AM (#8354799) Homepage
    if you're going to copy and paste, the least you could do is credit the source: a/how.html []
  • Re:Original Messages (Score:5, Informative)

    by orthogonal ( 588627 ) on Sunday February 22, 2004 @06:35AM (#8354835) Journal
    Yes but where can I get some original Nazi's to send them to?

    Well, the flippant answer is Argentina (Or Brazil).

    On a more serious note, you might try Latvia []; in 1998 about 500 Latvians, former members of the Waffen-SS marched through Riga to celebrate the 55th anniversary of the SS.

    Up until 1996, you could have looked in Indiana in the United States []:

    Kazys Ciurinskas, a former member of the Lithuanian SS division accused of killing Russian and Lithuanian Jews and POWs, lived in Indiana since the end of the war. Ciurinskas collected a $540 monthly pension from the German government since 1960 while living in the US and being a US citizen. In a 1995-97 United States of America v. Kazys Ciurinskas case the US District Court in Indiana stripped Ciurinskas of US citizenship.

    Interestingly, the amount of the pension paid to these former SS by the German government varies based on their final rank in the SS -- higher ranks get a bigger pension. Only recently -- and only after international pressure -- did the German government modify its pension law to strip the pension from war criminals, and even so, there is no requirement that any investigation be made of recipients, nor is there any mechanism to do so, so even known war criminals can continue to collect payments from the German government.

    Ironically, some war criminals even receive, in addition to their normal pensions what are called "victim's" pensions -- including those believed to have massacred American soldiers. The following [] was written in 1997, and thus may be slightly out of date:

    The well-respected German military historian Gerhard Schreiber estimates the number of war criminals receiving these extra payments from the German government at 50,000. Wolfgang Lehnigk-Emden, from Ochtendung near Koblenz, is one of the "victims." According to a German federal court, Lehnigk-Emden killed 15 unarmed women and children in Caiazzo near Naples in Italy in October 1943. Because Lehnigk-Emden was later injured (shot in the leg) while trying to escape from an allied POW camp and suffers a mild handicap, he receives an additional "victim" pension.

    Another current recipient of victim pensions is the former SS Hauptsturm-fuhrer Wilhelm Mohnke. Mohnke, who was a close confidant of Adolf Hitler and commandant of the "Fuhrerbunker" in Berlin during Hitler's last days. According to the US Department of Justice "there is very substantial evidence pointing to Wilhelm Mohnke's personal involvement in the perpetration of Nazi war crimes" -- for his role in the massacre of 72 American POWs in 1944 during the Battle of the Bulge.

    At the same time that Germany provides monthly pension payments to former members of the SS and war criminals, persons forced to be slave laborers for the Nazi regime get far less []:

    [U]nder an agreement... brokered by the U.S. and German governments, however, survivors of slave labor under the Nazis will be awarded only $790 each for back pay and a lump sum of $7,894 each in recognition of the 55-year delay. Those who were exploited as "forced labor," such as Nazi prisoners working in agriculture, will get a mere $5,000 each.

    So, frankly, any Old Folks (Pensioner's) Home in Germany should provide you with plenty of "original Nazis", living comfortably thanks to the largess of the current German government, while their victims -- those who survived at all, those who haven't died while waiting for their reparations -- continue to suffer.

    (Of course, I will now be modded down as an anti-German racist [], becaus

  • Re:Bummer (Score:2, Informative)

    by bearl ( 589272 ) on Sunday February 22, 2004 @08:39AM (#8354999)
    In the first paragraph of the order page:
    "Both addresses below do ship worldwide so ordering one shouldn't be a problem."

    Enigma-E Order Page []
  • Re:Who needs one? (Score:4, Informative)

    by 1u3hr ( 530656 ) on Sunday February 22, 2004 @08:57AM (#8355026)
    I'll drop one off at Bletchley on the way to picking up my Gray's Sports Almanac.

    The construction of the Enigma wasn't really the problem. The Enigma had been in use since the early 30s and the Poles knew exactly how they worked, and later shared that with the Allies as war grew closer and Poland was invaded. Decoding a message required knowing the settings used. At Bletchley Park they built "bombes" (originally following a Polish design) that could run decodes automatically hundreds of times faster than a real Enigma to try out the huge number of possible initial settings.

    Actually a great deal of their success in decoding was due to sloppy methods used by the Germans. Having messages begin in a predictable way was a "crib" that enabled good guesses to be made of the settings. And even more directly, capturing code books with schedules of code settings, as was done several times, (but not by the Americans as was depicted in U571). If the Germans had used the Enigmas with due care they never would have been cracked.

    However, it's rarely noted that the Germans were almost as good at decoding Allied signals. There's very little written about that, but I have seen notes that they could read just about any Royal Navy code, for instance.

  • Re:What's the point? (Score:1, Informative)

    by treat ( 84622 ) on Sunday February 22, 2004 @09:13AM (#8355062)
    I recall reading that the original Unix crypt(3) algorithm was based on the Enigma machine.

    Your wrongness is astounding. The fact that you were moderated up to 4 is proof that the moderation system has finally failed. I'll never read the comments on slashdot again. But I will fix this final error.

    crypt(1), the file 'encryption' utility is based on a simplified Enigma. crypt(3), the password hash with an 8 character limit that can be run 100,000 times a second on a modern machine, always used DES. Modern Unixes use an md5 or blowfish based hash that doesn't have an arbitrary length limit and is designed to be much slower. (and has variable round count and a larger salt space).

  • by Richard_L_James ( 714854 ) on Sunday February 22, 2004 @09:25AM (#8355095)
    maybe now you can emulate a replica of the Colossus, the computer used to decipher the Enigma, and have a mini-WW2 cryptography battle on your computer!

    Tony Sale [] the expert who rebuilt Colossus has also created a Virtual Bletchley Park [] part of his website which includes a Virtual Colossus [] that you can run via the web. However it is recommended to read the instructions (PDF) first! [].
  • by Anonymous Coward on Sunday February 22, 2004 @10:38AM (#8355288)
    True. One must remember that Enigma cracks were based on the predictability of the keys.

    Captured codebooks and poorly chosen keys (like the modern-day "password") really led to the compromise of the system as-implemented, not a compromise of the machine itself.
  • Re:What's the point? (Score:3, Informative)

    by Anonymous Coward on Sunday February 22, 2004 @10:40AM (#8355289)
    Your wrongness is astounding.

    Actually, his wrongness was very subtle. First of all, he may very well have read somewhere that crypt(3) was based on enigma. That is all he claimed, isn't it? (I guess careful reading of posts isn't required on SlashDot either, not even by people who are anal about accuracy.)

    Still, he did manage to pick out something called "crypt" as having been based on Enigma. My guess is that he uses Linux. His Linux distro probably no longer comes with a crypt utility (I ran into a problem with this recently and had to use this [] instead). Having no crypt utility, and thus no man page for a crypt utility, it's hard to remember that the crypt utility used to be crypt(1). Perhaps he just assumed that some code which was once a separate program called crypt has since been library-ized, keeping the same man page location?
  • by Ragica ( 552891 ) on Sunday February 22, 2004 @11:28AM (#8355493) Homepage
    Python [], infinitely useful "out of the box", has come bundled with a module called "rotor []" which is basically an enigma-like scrambler. You can add as many rotors as you like to your digital enigma-like machine.

    Sadly this module has been marked for deprecation in python 2.3, though it is still there. I found the module very useful for some things --- a simple, light weight encryption can be a handy thing. Everyone knows that it is weak encryption these days though... but still useful, in my opinion.

  • I donno.. (Score:4, Informative)

    by nurb432 ( 527695 ) on Sunday February 22, 2004 @11:31AM (#8355511) Homepage Journal
    I wouldnt put Steve on the same level as Woz.

    Steve is smart, dont get me wrong, and did a lot of cool things ( yes i remember back then too, or even earlier with Popular Electronics.... ) but Steve had much more modern chips to work with, and used databooks for 'ideas' far too often..

    Woz had to come up with the stuff from scratch...
  • by FeriteCore ( 25122 ) on Sunday February 22, 2004 @11:53AM (#8355616)
    It is a much more astounding wrongness to wrongly accuse another of astounding wrongness.

    UNIX, and by implecation the encryption of passwords in /etc/passwd predates the publication of DES by a number of years. It would have been impossible for the password hash to have always used DES.

    I was actualy USING Unix version 7 when the adoption of DES as a standard was being debated. My Version 7 UNIX manuals (all two volumes) are boxed away somewhere. I recall a warning in the manual about the enigma based crypt having known weakness. My understanding was that this same algorithm was used for the /etc/passwd hash, but I cannot state that with certainty at this late date. What is certain is that it wasn't DES.
  • by Handpaper ( 566373 ) on Sunday February 22, 2004 @01:27PM (#8356111)
    Keep in mind that 256,000 bytes is only 250 MB, without compression I can fit 3 of those on a CD
    Er.. 256,000 bytes is less than 256Kb - you can fit almost 3000 of them on a CD. Keys are supposed to be as random as possible - if it compresses significantly its not random (listen (cat to /dev/dsp) to a compressed and uncompressed file and you'll hear whet I mean)

  • Enigma decrypt (Score:5, Informative)

    by earthforce_1 ( 454968 ) <<moc.oohay> <ta> <1_ecrofhtrae>> on Sunday February 22, 2004 @01:37PM (#8356162) Journal
    Decrypting Enigma messages were made much easier, because of human weaknesses. The operator would first send a 3 letter position for the plugboard in plaintext, and the operator would chose the remaining 3 for the rotor. The Bletchley park decoders could easily guess that if BER was sent, they guy on the other end would set his rotors to LIN. LON would be followed by -DON. HIT by -LER. Another Enigma operator would always use the initials of his French girlfriend!

    Decoding was also made easier by knowing part of the content of the message. Loyal Nazis were always fond of closing their encrypted messages with a hearty "Heil Hitler" which of course aided the British immensely.
  • And the real irony (Score:2, Informative)

    by pjt33 ( 739471 ) on Sunday February 22, 2004 @01:40PM (#8356177)
    The real irony is that during the Cold War, the USSR actually used an uncrackable cipher - the one-time pad. Unfortunately, due to problems producing and distributing key material, they ended up being two-time pads, and project VENONA managed to exploit that.
  • by calidoscope ( 312571 ) on Sunday February 22, 2004 @04:57PM (#8357182)
    US had nothing to do with it.

    Not quite true - the US did supply a good number of the Bombes used for determing the steckers and wheel settings.

    What made the Enigma easy to crack was that the signals through the rotors were reflected - which greatly limited the encoding space.

    What the Poles did in cracking the Enigma was nothing compared to what Friedman did in cracking Japan's "Purple Code". The Poles knew how the Enigma was built, Friedman had to deduce how the "Purple" box worked.

  • by PeterCook ( 673216 ) <peter@cook.temple@edu> on Monday February 23, 2004 @12:02AM (#8359618) Homepage
    Yeah - yeah - all jokes aside this is a WWII geek machine - it was easy to assemble and works great. I give the creators of this credit for the hard work they put in - they even delivered a completed one to the Bletchley Trust Director for display. On the side I have been a consultant to Bletchley Park - supporter and a personal friend of a woman who worked in the registration room at Bletchley during the war. She shared many of her photos, artifacts and stories about what it was like to work somewhere and then never being able to tell anyone what you did there until 35 years later (Secrets Act). Her parents died not knowing what she did for her country. If you haven't been there - take the train to Bletchley (from Euston station in London north about an hour & a half) next time you in the UK - 200 yards away from the station is the main gate of the complex - you will be blown away by what's there. One of the problems with the comments I have seen here is that most of the knowledge about BP from folks on this side of the Atlantic is either incomplete or misinformed. At BP they had 12 Colossus computers working by the end of the war. A replica was rebuilt in 1996 from scratch and is still working - including the unique paper tape/proximity fuse system used to enter information - read all of Tony Sale's site to understand it. At the end of the war all but one of the Colossus computers were destroyed under the British War Secrets act and the building housing them was demolished in the 1960's - all that's left is the granite front step. All blueprints and all photos but about 3 were destroyed. The last Colossus was sent to the British version of the NSA - GCHQ in Cheltenham. It was reported it was also destroyed after a few years. Americans know very little about BP or Colossus. One of the reasons why various codes were cracked was that some the Germans became lazy and started beginning the codes with familiar words, phrases, and even girlfriend's names - like putting a personal stamp on the message. Bletchley Park is in the process of creating and preserving the unique information technology history that took place there. They are a very unique treasure - you won't find them mentioned in UK travel books but I am going to change that. Hooray for the Enigma-E! - personally I was amused that this fully working encryption device (BTW not all German codes were deciphered) was sent to me and passed through US Customs with the label "Electronic Toy" on it. This device is still a useful machine and definitely not a toy.

Adding manpower to a late software project makes it later. -- F. Brooks, "The Mythical Man-Month"