Re: [Dtls-iot] Secure Time (again)

Eric Rescorla <ekr@rtfm.com> Tue, 11 August 2015 13:34 UTC

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From: Eric Rescorla <ekr@rtfm.com>
Date: Tue, 11 Aug 2015 08:33:40 -0500
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To: Hannes Tschofenig <hannes.tschofenig@gmx.net>
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Cc: dtls-iot@ietf.org, Michael StJohns <msj@nthpermutation.com>
Subject: Re: [Dtls-iot] Secure Time (again)
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On Tue, Aug 11, 2015 at 5:34 AM, Hannes Tschofenig <
hannes.tschofenig@gmx.net> wrote:

> Hi Mike,
>
> yes, there have been discussions about removing this server-provided
> time information in TLS 1.3.
>

This is already done.

-Ekr




> Although the current profiles focus on TLS 1.2 this might cause some
> problems in the future.
>
> Ciao
> Hannes
>
>
> On 08/09/2015 08:23 PM, Michael StJohns wrote:
> > On 8/7/2015 11:42 AM, Hannes Tschofenig wrote:
> >> It turns out that TLS has a way to communicate time information from the
> >> server to the client as part of the ServerHello message. Of course, it
> >> is not a good idea to trust every server when they return time
> >> information since this allows an adversary to trick the client into
> >> accepting an expired certificate.
> >
> > I think this has been deprecated and removed for TLS1.3?
> >
> > Mike
> >
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