Re: [TLS] The TLS_FALLBACK_SCSV time bomb (was: Re: Working Group Last Call for draft-ietf-tls-downgrade-scsv-00)

Bodo Moeller <bmoeller@acm.org> Mon, 20 October 2014 22:51 UTC

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Date: Tue, 21 Oct 2014 00:51:05 +0200
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From: Bodo Moeller <bmoeller@acm.org>
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Subject: Re: [TLS] The TLS_FALLBACK_SCSV time bomb (was: Re: Working Group Last Call for draft-ietf-tls-downgrade-scsv-00)
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Andrei Popov <Andrei.Popov@microsoft.com>:

It would be nice to keep TLS extensions optional; unfortunately, TLS
> extensions mechanism is already used to patch protocol security issues:
> renegotiation info, extended master secret extensions come to mind. I think
> we've crossed this bridge a long time ago.


You should be able to get away without the actual renegotiation_info
extension if you don't support renegotiation.

Bodo