Ask HN: How long would it take to crack the Enigma Code now?

13 points by mangeletti ↗ HN
I wonder about this; how long would it take, without the specific historical knowledge we have about the Enigma Code / Enigma Machines, but with our current computing power / security expert man power / knowledge of encryption and math in general, etc., to crack similarly encrypted messages in the present day.

4 comments

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mangeletti, may I refine your scenario? Chuck Klosterman style + additions.

>>>

Suppose that the Enigma Machine had never happened (but the rest of history somehow came out the same--any innovations that came directly from the Enigma or related work at Bletchley Park, etc, those innovations still happened, so all of our tech and history are the same, sans Enigma machine).

Now suppose that some organization (ISIS? USA? Anonymous? China? The Mafia? Russia? Whatever you like.) suddenly obtains enough Enigma machines (they have wifi now instead of whatever they had before) to carry out all their sensitive communications.

Further suppose that you are a leader of some sort and your organization is in direct conflict with the Enigma-using organization. You can intercept the messages, but as of yet you are unable to read them. You must find a way to read those messages!

What are your first orders?

1. Run entropy measurement. (http://www.fourmilab.ch/random/)

2. If results from #1 are high, prioritize stealing an Enigma.

3. If results from #1 are low, prioritize performing classical crypto work: interactive use of frequency analysis, etc.

It is worth noting that Enigma machine simulators exist.
I suspect it's hard to answer your question meaningfully. How do we ignore what we know about Enigma and still have modern cryptography?

It depends on which Enigma code and how much knowledge you know about the context of the message. Looking around, you can start with https://www.cryptool.org/en/cryptool2 :

> CrypTool 2 provides a variety of cryptanalytical tools to analyze or even break classical and modern ciphers. With the current version you can, for instance, apply a ciphertext-only attack on an Enigma-encrypted ciphertext

https://en.wikipedia.org/wiki/Cryptanalysis_of_the_Enigma#Si... points to http://www.tandf.co.uk/journals/pdf/papers/ucry_06.pdf from 10 years ago, which say that in about 6 weeks, "a total of ten breaks were achieved".

The WP page also refers to https://enigma.hoerenberg.com/index.php?cat=M4%2520Project%2... , which took 10 years to decrypt (calendar time, not CPU time). See https://enigma.hoerenberg.com/cms/download.php?cat=65_M4%20P... for details.