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Re: [TLS] Verify data in the RI extension?

Stefan Santesson <stefan@aaa-sec.com> Fri, 27 November 2009 15:10 UTC

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Date: Fri, 27 Nov 2009 16:08:54 +0100
From: Stefan Santesson <stefan@aaa-sec.com>
To: Nikos Mavrogiannopoulos <nmav@gnutls.org>
Message-ID: <C735AA16.6BDF%stefan@aaa-sec.com>
Thread-Topic: [TLS] Verify data in the RI extension?
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Subject: Re: [TLS] Verify data in the RI extension?
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No I don't have any scenario (and I said so).

This was part of a principal (theoretical) argument.

/Stefan

On 09-11-27 3:30 PM, "Nikos Mavrogiannopoulos" <nmav@gnutls.org> wrote:

> On Thu, Nov 26, 2009 at 10:28 AM, Stefan Santesson <stefan@aaa-sec.com> wrote:
> 
>> On the contrary, I find it to be good security design not to exchange that
>> value as it:
>> 
>> 1) Reduce information leakage to an attacker
> 
> Hello,
>  How would that be? What scenario do you have in mind? This value has
> already been exchanged in the initial finished message exchange and
> was protected under the same ciphersuite. Why would this exchange be
> less secure? If the attacker can decrypt and see this value, then he
> can also see the initial finished value. No new information is given
> to him.
> 
> 
> regards,
> Nikos

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