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After Weeks of Trying, UK Cryptographers Fail To Crack WWII Code

Posted by timothy on from the reopen-bletchley-park dept.

An anonymous reader writes "A dead pigeon discovered a few weeks ago in a UK chimney may be able to provide new answers to the secrets of World War II. Unfortunately, British cryptographers at the country's Government Communications Headquarters (GCHQ) have been unable to crack the code encrypting a message the bird was tasked with sending and say they are confident it cannot be decoded 'without access to the original cryptographic material.'"

14 of 263 comments (clear)

  1. No surprise there by Anonymous Coward · · Score: 5, Insightful

    Given that the original message looks supiciously like it was encoded with a one time pad, it's really not at all surprising that they can't crack it without the relevant pad. Which was probably destroyed a long time ago.

    1. Re:No surprise there by v1 · · Score: 5, Informative

      One time pads are not impossible to crack, provided you have some clues about detecting a successful decoding.

      [ citation needed ]

      Here, let me help you.

      citation

      In cryptography, the one-time pad (OTP) is a type of encryption which has been proven to be impossible to crack if used correctly. Each bit or character from the plaintext is encrypted by a modular addition with a bit or character from a secret random key (or pad) of the same length as the plaintext, resulting in a ciphertext. If the key is truly random, as large as or greater than the plaintext, never reused in whole or part, and kept secret, the ciphertext will be impossible to decrypt or break without knowing the key.

      So unless you classify the key as a "clue" (rather than a cluebat) you need to rethink that.

      --
      I work for the Department of Redundancy Department.
    2. Re:No surprise there by jspoon · · Score: 5, Funny

      Grandparent is getting OTP mixed up with ROT13. I do that all the time. It cost me my job once.

    3. Re:No surprise there by l0ungeb0y · · Score: 5, Funny

      Messages small enough to be carried by pigeon were most likely necessarily small

      So you're saying that this message was quite literally a "tweet".

    4. Re:No surprise there by mysidia · · Score: 5, Informative

      even two letters right next to each other may not represent the same letter in the original plaintext..

      Any cipher worth its salt will have this characteristic.

      A one time pad is a mixing operation; a combination of random data with the plaintext being protected, using an operation that preserves entropy; which means that none of the randomless from the one time pad bits are lost EVEN though the plain message being encrypted is non-random, the result will have exactly as much randomness as the more random of the two bits being mixed, and therefore it is mathematically impossible to discover the value of a single bit of plaintext, without knowing the corresponding bit of one time pad.

      Nor is it possible to determine the value of any single bit of one time pad, without knowing the corresponding plaintext bit.

      Any attack requires discovering the value of the one time pad through an outside source, or exploiting a weakness in the pad, such as key reuse, OR inadequate random number generator used to produce the pad.

      The only thing you can ascertain about the one time pad by looking at the enciphered message, is its maximum potential length, since you can see the number of symbols that are printed on the card, and that will be a finite number.

    5. Re:No surprise there by OneAhead · · Score: 5, Interesting

      Now you're just making a fool of yourself. People already linked you to a wikipedia page that explains in detail why you're wrong, yet you stubbornly refuse to read it (or perhaps you're too daft to understand what it says?)

      Here's a demonstration. From TFA, the secret message is:
      AOAKN HVPKD FNFJU YIDDC
      RQXSR DJHFP GOVFN MIAPX
      PABUZ WYYNP CMPNW HJRZH .
      NLXKG MEMKK ONOIB AKEEQ
      UAOTA . RBQRH DJOFM TPZEH
      LKXGH RGGHT JRZCQ FNKTQ .
      KLDTS GQIRU AOAKN

      My sources are telling me that "AOAKN" is most likely the identifier of the OTP or code page that was used, so the actual content of the message is
      HVPKD FNFJU YIDDC RQXSR
      DJHFP GOVFN MIAPX PABUZ
      WYYNP CMPNW HJRZH NLXKG
      MEMKK ONOIB AKEEQ UAOTA
      RBQRH DJOFM TPZEH LKXGH
      RGGHT JRZCQ FNKTQ KLDTS
      GQIRU

      Being a 1337 cryptography expert, I determined that the code page in the sender's code book started with:
      SBXDZ CUYSG ECWKO CMRSZ
      JRGOH DIRFA JRWEP LFXRK
      OLULB XHHAW UGKLL NUUKT
      JQPKX LMUGR IGRCC AHKCW
      OKMZZ LQOSK PPGNH YPPVW
      NRVDT RNHYD CNCCY RUVJO
      VCNNA
      Don't believe me? Go to this page, copy-paste the above "actual content" in the field that says "input" and the key in the field that says "key", and click decode.

      Oh wait, I was wrong, the real key is:
      ZTLJV VJXRU VERZP YMUND
      PYLYB WBHJV ZUWCR ESJNL
      FMYUI KMCKU HWYID NIJTM
      ZBITS VNBFI TGIWG MLKQS
      RMQLD PWASI AHNAS LHFBN
      PWYUN XRTPM MVDFU HXKMO
      IUUAK

      Allright, I'm just messing with you, it's
      JHVGR QUHCQ YFZAC EILSG
      YVTCW PABZG QALLG HVBDG
      OLAZV LGLAS QJGWZ WHVRY
      YROWQ XBAPU WTIEY UTOHI
      YXZRU ALALV OPGXD USLCW
      YSBDI GNILZ OWTSM TUMCB
      PZANC

    6. Re:No surprise there by gadzook33 · · Score: 5, Interesting

      Actually I read something interesting about WWII One Time Pads. Apparently the pads were generated by women (typically) drawing ping pong balls out of a hopper and writing down the letters. The problem was if they drew the same letter multiple times in a row, they might put it back thinking that it wasn't "random" enough. Of course, in doing so they changed the distribution of letters to no longer be uniform. My understanding is that this very quickly erodes the cryptographic integrity of the one-time pad to the point where you can start to look for the plaintext based on letter frequency. I'm not saying that's applicable here (and I have to imagine the cryptographers would have looked at this) but interesting nonetheless.

    7. Re:No surprise there by Anonymous Coward · · Score: 5, Funny

      That last batch activated my copy of Windows XP.

  2. Easy! by Anonymous Coward · · Score: 5, Funny

    Wenn ist das Nunstück git und Slotermeyer? Ja! Beiherhund das Oder die Flipperwaldt gersput!

    1. Re:Easy! by Anonymous Coward · · Score: 5, Funny

      Wenn ist das Nunstück git und Slotermeyer? Ja! Beiherhund das Oder die Flipperwaldt gersput!

      HHAHAHAHAHAHAHAHAHAHAHAHA!

      *dies*

  3. Its worse than that. by Anonymous Coward · · Score: 5, Interesting

    My Aunt was a radio communication specialist in the channel islands where they communicated with the underground and later the anti Nazis within the third reich. My Dad was involved in counter espionage within Great Britton. They were both recruited by the Canadian military and then trained by the combined British and Canadian military intelligence division long before the US joined in.

    Not only was key info done with one time cipher it also used specialist language. For instance the word pie after decryption might be construed to be to mean supplies. Only the individuals who were taught the language could decode it and no more than a few individual agents sending info from within Germany or France used the same code specific language.

    If the pigeon corpse was from D Day then it would have been really early in the landing. As the beach head was secured the code receiving specialist people moved in to undisclosed places in Normandy. Are they absolutely certain the pigeon was from D Day? If not it may have been from other sources as my aunt told me there was some underground agents using them before 1944...Some even in the Dieppe region!

  4. Re:lol by Anonymous Coward · · Score: 5, Funny

    Really, Mr. Ballmer, you need to take some anger management classes.

  5. Re:Weeks by Deadstick · · Score: 5, Informative

    You would seem to miss the point. Here's a message encrypted with a one-time pad: WXYZ. Want to brute-force it? OK, try all the permutations of four letters that can exist in the OTP (36^4 of them, if the pad accommodates English letters and digits). Spoiler alert: One of those permutations will yield LOVE. Another will yield HATE. Which one is the correct message?

  6. Re:It's not ROT13 by marcosdumay · · Score: 5, Funny

    What did you run twice? The XOR one time pad or the ROT-13?

    --
    Rethinking email