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Re: [TLS] CCS and key reset and renegotiation

Watson Ladd <watsonbladd@gmail.com> Thu, 05 June 2014 15:27 UTC

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Date: Thu, 5 Jun 2014 08:25:26 -0700
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From: Watson Ladd <watsonbladd@gmail.com>
To: Rich Salz <rsalz@akamai.com>
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Subject: Re: [TLS] CCS and key reset and renegotiation
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On Jun 5, 2014 8:12 AM, "Salz, Rich" <rsalz@akamai.com> wrote:
>
> Have folks seen this yet?
>
>
http://ccsinjection.lepidum.co.jp/blog/2014-06-05/CCS-Injection-en/index.html
>
>
>
> I think it adds weight to my concern about using ChangeCipherSpec to do
key reset.  I still prefer the trade-offs of having a “slow the TLS but
keep the TCP layer open” and starting over.  Much simpler to prove it’s
correct.

What can change when that happens? Furthermore, rekeying is a matter of
getting more PRF output: how does that introduce security concerns.

I don't see why the incompetence of implementors should govern our
decisions. If something cannot be implemented correctly it must be
removed,  but why is rekeying such a thing?
>
>
>
>                 /r$
>
>
>
> --
>
> Principal Security Engineer
>
> Akamai Technologies, Cambridge, MA
>
> IM: rsalz@jabber.me; Twitter: RichSalz
>
>
>
>
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