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Article #2Prime generation, a possible weakness in PGP?
From: Ari Huttunen
Date: Sun, 27 Sep 1992 15:45
Date: Sun, 27 Sep 1992 15:45
18 lines
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1257 bytes
I am concerned about the primeness of the prime numbers that PGP generates. This is how they are done: - first throw away numbers that are divisible by small primes - then use Fermat's theorem 4 times (Fermat's theorem: if b**(n-1) != 1 (mod n), then 'n' cannot be a prime. This requires that 'b' and 'n' are relatively prime.) My concern is the number of rounds of the Fermat test. It's only 4. I would not trust this level of primeness. Also, the resulting number might be a Carmichael number. (So it would pass any number of such tests.) -- ............................................................................... Ari Huttunen Any similarity to other alien life forms is purely coincidental. <Alien 3 misquote>
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Newsgroups: alt.security.pgp,sci.crypt Path: arc1-ca.pugleaf.net!sparky!uunet!mcsun!news.funet.fi!ajk.tele.fi!funic!news.cs.hut.fi!cs.hut.fi!Ari.Huttunen From: Ari.Huttunen@hut.fi (Ari Huttunen) Subject: Prime generation, a possible weakness in PGP? Message-ID: <ARI.HUTTUNEN.92Sep27174550@laphroaig.cs.hut.fi> Lines: 18 Sender: usenet@cs.hut.fi (Uutis Ankka) Organization: Helsinki University of Technology, Finland Distribution: alt Date: Sun, 27 Sep 1992 15:45:52 GMT