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, 02 Oct 2013 14:23:03 -0700
From: Seth David Schoen <schoen@eff.org>
To: Adam Langley <agl@google.com>
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Cc: "tls@ietf.org" <tls@ietf.org>
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> Senior Staff Technologist https://www.eff.org/ Electronic Frontier Foundation https://www.eff.org/join 815 Eddy Street, San Francisco, CA 94109 +1 415 436 9333 x107
- [TLS] Downgrade prevention with authenticated lis… Seth David Schoen
- Re: [TLS] Downgrade prevention with authenticated… Adam Langley
- Re: [TLS] Downgrade prevention with authenticated… Seth David Schoen