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

Yoav Nir <ynir@checkpoint.com> Mon, 30 November 2009 07:55 UTC

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From: Yoav Nir <ynir@checkpoint.com>
To: Stefan Santesson <stefan@aaa-sec.com>
Date: Mon, 30 Nov 2009 09:55:17 +0200
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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On Nov 30, 2009, at 9:11 AM, Stefan Santesson wrote:

> 
> 
> 
> On 09-11-30 1:14 AM, "Marsh Ray" <marsh@extendedsubset.com> wrote:
> 
>> Stefan Santesson wrote:
>>> 
>>> The real security advantage of implicit is that you know that the opponent
>> 
>> I agree that is possibly an advantage, but a very weak advantage.
>> 
> 
> Well, It's not weak or strong in a cryptographic sense. The weakness is
> totally dependent on whether implementers get this right or not. The problem
> is that you can't tell whether they did since it doesn't show.
> If they get it right, there is no weakness, if some or any get it wrong, it
> may significantly reduce the value of this effort.
> 
> With implicit, implementers can't get it wrong and still produce a valid
> finished message.
> 
> I personally think this is a significant advantage.

+1

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