Re: [TLS] WGLC for draft-ietf-tls-exported-authenticator

Roelof duToit <r@nerd.ninja> Wed, 09 May 2018 01:25 UTC

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From: Roelof duToit <r@nerd.ninja>
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Date: Tue, 8 May 2018 21:24:53 -0400
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To: Martin Thomson <martin.thomson@gmail.com>, "<tls@ietf.org>" <tls@ietf.org>
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Subject: Re: [TLS] WGLC for draft-ietf-tls-exported-authenticator
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If the use of the mechanism is not negotiated on the TLS level then I would appreciate it if the “Security Considerations” section of the draft could be amended to include a paragraph that warns potential implementors that protocol-agnostic middleboxes will break the mechanism without any clear failure indicators.

> On May 8, 2018, at 8:13 PM, Martin Thomson <martin.thomson@gmail.com> wrote:
> 
> On Wed, May 9, 2018 at 2:20 AM Roelof duToit <r@nerd.ninja> wrote:
> 
>> I understand that there is not really anything to negotiate per se, but
> would it not be prudent to add a TLS extension to negotiate support for
> exported-authenticator in the TLS layer prior to using it in the
> application layer?
> 
> We don't signal the potential need for exporters.  I see no reason to
> signal this either.  Any signaling necessary really belongs at the higher
> layer.