Re: [TLS] Proposed change in TLS-Flags

Nick Harper <nharper@google.com> Tue, 30 June 2020 23:45 UTC

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From: Nick Harper <nharper@google.com>
Date: Tue, 30 Jun 2020 16:45:11 -0700
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To: David Schinazi <dschinazi.ietf@gmail.com>
Cc: Yoav Nir <ynir.ietf@gmail.com>, "<tls@ietf.org>" <tls@ietf.org>
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Subject: Re: [TLS] Proposed change in TLS-Flags
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This was discussed in the WGLC thread (
https://mailarchive.ietf.org/arch/browse/tls/?gbt=1&index=973qdoi0PmJbJzNU7Y-eC_a-WaI)WaI).
I haven't seen any proposals of when it would be useful for a server to
send a flag unsolicited.

On Tue, Jun 30, 2020 at 4:31 PM David Schinazi <dschinazi.ietf@gmail.com>
wrote:

> Hi Yoav,
>
> Could you elaborate on the rationale for this change please?
> I was assuming that the ability for servers to send extensions not
> requested by clients was useful.
>
> Thanks,
> David
>
> On Mon, Jun 29, 2020 at 2:34 PM Yoav Nir <ynir.ietf@gmail.com> wrote:
>
>> Hi
>>
>> I’ve just submitted the following PR:
>>
>> https://github.com/tlswg/tls-flags/pull/4
>>
>> Three changes:
>>
>>    - It is no longer allowed to send an empty flags extension.  If you
>>    don’t support any flags, don’t send the extension.
>>    - The server is no longer allowed to respond with flag types that the
>>    client didn’t indicate support for first.
>>    - I’ve split the extension description section into a format section
>>    and a rules section
>>
>>
>> Please comment. Barring any objections, I’ll merge the PR just before the
>> submission deadline.
>>
>> Yoav
>>
>> _______________________________________________
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>>
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