Re: [TLS] Downgrade prevention with authenticated list of ciphersuites?

Seth David Schoen <schoen@eff.org> Wed, 02 October 2013 21:23 UTC

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Date: Wed, 2 Oct 2013 14:23:03 -0700
From: Seth David Schoen <schoen@eff.org>
To: Adam Langley <agl@google.com>
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Subject: Re: [TLS] Downgrade prevention with authenticated list of ciphersuites?
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Adam Langley writes:

> TLS already authenticates the ciphersuite lists of both sides in the
> final Finished messages.
> 
> Are you worried about misconfigured servers, or False Start, or
> version fallback causing certain cipher suites to disappear?

Nope, I just got confused about the nature of the version downgrade and
thought there was _also_ an effectively-unauthenticated transmission
of the ciphersuite list.  I agree that the Finished message makes my
suggestion superfluous!

-- 
Seth Schoen  <schoen@eff.org>
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