Article View: sci.crypt
Article #1398Re: PGP weak on long messages (was: Re: pgp2.0 ... key length?)
From: Keith Lewis
Date: Tue, 06 Oct 1992 20:07
Date: Tue, 06 Oct 1992 20:07
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In article <1992Oct04.084900.19815@spillman.uucp>, tye@spillman.uucp (E. Tye McQueen) writes: >lewis@aera8700.mitre.org (Keith Lewis) writes: >)PGP is essentially RSA performed on a bitmask which is used repeatedly on >)a single message. > >Doesn't reusing the (encrypted) bit mask make long messages fairly >easy to crack if you have ideas as to the content of the plain text? >I guess the message would best be several times the length of the >bit mask for this to work. I retracted this statement after being corrected via email. It seems that the scheme is a little more complicated than that. It uses the IDEA cipher and encrypts *that* key using RSA. It might still be weak on very, very long messages, but nowhere near as weak as a simple bitmask. Keith Lewis klewis@mitre.org "Mr. Cheap" I don't dance to music; music dances to me. Email me for my PGP key. The above may not (yet) represent the opinions of my employer.
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From: lewis@aera8700.mitre.org (Keith Lewis)
Subject: Re: PGP weak on long messages (was: Re: pgp2.0 ... key length?)
Message-ID: <1992Oct6.200728.15608@linus.mitre.org>
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Date: Tue, 6 Oct 1992 20:07:28 GMT
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