Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!iuvax!cica!tut.cis.ohio-state.edu!pt.cs.cmu.edu!b.gp.cs.cmu.edu!ralf
From: ralf@b.gp.cs.cmu.edu (Ralf Brown)
Newsgroups: comp.sys.ibm.pc
Subject: Re: UNIX-like crypt function
Keywords: crypt unix ibm-pc
Message-ID: <5927@pt.cs.cmu.edu>
Date: 22 Aug 89 00:14:09 GMT
References: <855@eutrc3.urc.tue.nl> <2152@netcom.UUCP> <17369@ut-emx.UUCP> <310@cs.columbia.edu>
Organization: Carnegie-Mellon University, CS/RI
Lines: 30

In article <310@cs.columbia.edu> amb@cs.columbia.edu (Andrew Boardman) writes:
}In article <17369@ut-emx.UUCP> nghiem@walt.cc.utexas.edu (Alex Nghiem) writes:
}>Didn't I read somewhere that Unix encryption was restricted to
}>U.S.A. and not for export? What happens if the function gets
}>in the "wrong" hands through the network?
}
}Not a lot.  Picture this: person who is in another country with his
}machine on the Internet ftp's the appropriate crypt binary (or source
}if he has it) via one of his accounts in the US.  It's quite probably
}happened quite a few times; it's not a high-security item.  It's just
}Officially Frowned Upon for some terribly good reason which escapes me
}at the moment.  (This last bit was explained to me by an ex-NSA friend
}who's now at DEC of all places.)

Besides, the DES algorithm has been written up any number of times in 
easy-to-get publications....  I read such a write-up a couple of years ago,
and the only really subtle part is the exact values to use in the substitution
tables.  In a nutshell, it splits, substitutes, transposes, and recombines
64 bits, combining them with the key along the way, then repeats that same
process another fifteen times.

Seems kind of silly to prohibit the export of an implementation of an 
algorithm that is sufficiently well-known outside the US for a non-US 
implementation to be shipped back *into* the US....  (check comp.sources.unix
a coupla volumes back for "des-no-usa")
-- 
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