Schneier on Security

Clive Robinson • September 8, 2024 11:50 AM

@ ALL, Bruce,

Re : Cracking crypto to get at crypto.

This is related technically to the design of the Boris Hagelin modified “coin counting mechanism” that got used in the M209 “stream cipher”[1], but more modern.

The history of South Africa and the ANC is complex to put it politely, and actually of not much relevance to this Cryptanalysis store.

Except to say that the ANC had long distance communications via networks that they had better than good reason to believe were probably less secure than using radio broadcasts from random locations.

So like the SOE in WWII they ended up using the “One Time Pad”. Or in the case of the ANC a near facsimile of what they assumed was a strong “key stream generator” that produced “electronic pads” that were put on floppy discs and smuggled into SA by various trusted people.

Well as history shows South Africa changed and the ANC became normalised into the political process and nolonger needed to use the Crypto they had developed.

So the man who developed it put it all on floppy disks as a Zip Archive with encryption. And in some respects –the password– forgot about them.

This is the story of cracking the zip files and recovering the crypto programs used thus the algorithm used to generate the key stream used in Pad form,

https://blog.jgc.org/2024/09/cracking-old-zip-file-to-help-open.html

[1] Technically although quite simple the M209 was more secure than the German Enigma when used properly. As I’ve noted before the Hagelin coin counting mechanism had a very large key space, however most of the keys were in fact not very strong at all. Something that the NSA –formed after WWII– took significant advantage of as old Hagelin systems using the “coin counting mechanism” appeared in other countries. As we also now know the man that “expressed regrets” about the Hagelin system being accepted by the US William Friedman, had befriended Boris Hagelin who had set up Crypto AG in Zug Switzerland. Friedman persuaded Boris to deliberately weaken his crypto systems sold to many countries world wide so the NSA knowing the secret could easily read a foreign nations confidential traffic.