Re: [Cfrg] Attacker changing tag length in OCB
Peter Gutmann <pgut001@cs.auckland.ac.nz> Fri, 31 May 2013 04:06 UTC
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From: Peter Gutmann <pgut001@cs.auckland.ac.nz>
To: "cfrg@ietf.org" <cfrg@ietf.org>, Rene Struik <rstruik.ext@gmail.com>
Thread-Topic: [Cfrg] Attacker changing tag length in OCB
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Date: Fri, 31 May 2013 04:05:59 +0000
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Subject: Re: [Cfrg] Attacker changing tag length in OCB
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Rene Struik <rstruik.ext@gmail.com> writes: >History suggests that lots of security vulnerabilities arise precisely >because of these poor choices (or lack of knowledge of impact of policy on >security services offered). One could shield against poor choices in various >ways, e.g., by using as key k:=Hash(K, TagLength). +1. It's not a case of "will this be misused?", it's a case of "how long will we have to wait before the first misuse occurs?". Peter.
- Re: [Cfrg] Attacker changing tag length in OCB Peter Gutmann
- Re: [Cfrg] Attacker changing tag length in OCB Dan Brown