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Re: [TLS] Working Group Last Call for draft-ietf-tls-downgrade-scsv-00

Manuel Pégourié-Gonnard <mpg@polarssl.org> Mon, 20 October 2014 18:57 UTC

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Date: Mon, 20 Oct 2014 20:56:59 +0200
From: Manuel Pégourié-Gonnard <mpg@polarssl.org>
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To: Brian Smith <brian@briansmith.org>, Bodo Moeller <bmoeller@acm.org>
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Cc: "Joseph Salowey (jsalowey)" <jsalowey@cisco.com>, "<tls@ietf.org>" <tls@ietf.org>
Subject: Re: [TLS] Working Group Last Call for draft-ietf-tls-downgrade-scsv-00
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On 20/10/2014 19:32, Brian Smith wrote:
> For compatibility reasons, clients should put the renegotiation info and
> TLS_FALLBACK_SCSV at the end of the cipher suite list, to avoid this bug
> and similar bugs in other server software. This should be added to the
> draft too.
> 
Currently, PolarSSL puts the renego SCSV at the beginning of the list and we
didn't get any report of interop issues so far. However, if there's consensus
that it's safer to put the SCSV at the end, I'll follow your advice and change that.

(For the fallback scsv, obviously I added it at the end since we want to interop
with the current version of OpenSSL.)

Manuel.

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