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Re: [TLS] Final nail in the coffin for cleartext SNI/ALPN in TLS 1.3

Ralf Skyper Kaiser <skyper@thc.org> Thu, 07 November 2013 19:55 UTC

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Date: Thu, 07 Nov 2013 19:54:57 +0000
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From: Ralf Skyper Kaiser <skyper@thc.org>
To: Yoav Nir <ynir@checkpoint.com>
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Subject: Re: [TLS] Final nail in the coffin for cleartext SNI/ALPN in TLS 1.3
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Hi,


On Thu, Nov 7, 2013 at 7:46 PM, Yoav Nir <ynir@checkpoint.com> wrote:

>  IMO, if both sites are either collocated on the same machine, or hosted
> behind the same SSL accelerator, they already share enough that multi-SAN
> is not a bad thing.
>
>  With SNI is it currently stands, the site you are looking for is sent in
> the clear. If we keep the choose-certificate functionality in 1.3, we still
> leave it exposed in either the SNI or in the certificate that the server
> sends. A generic certificate is the only one that hides what the client is
> browsing.
> TLS mailing list
>

No, SNI can be send encrypted in TLS 1.3 with 'Reduced RT with Privacy' as
presented by Eric yesterday. Key Exchange is done before SNI is send and
auth is done as last. (What's now cleartext would then require
detectable-active attack).

regards,

ralf

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