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Re: [TLS] Interaction between cookies and middlebox compat mode

Matt Caswell <matt@openssl.org> Fri, 29 December 2017 10:54 UTC

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To: Eric Rescorla <ekr@rtfm.com>
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From: Matt Caswell <matt@openssl.org>
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Date: Fri, 29 Dec 2017 10:54:41 +0000
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Subject: Re: [TLS] Interaction between cookies and middlebox compat mode
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On 28/12/17 18:06, Eric Rescorla wrote:
>     I must be missing your point. According to the spec as it stands even
>     with a stateful server I MUST ignore a CCS that comes first. Since this
>     is a stateful server it may end up negotiating TLSv1.2 - which requires
>     us to abort the handshake if the CCS comes first. No sensible
>     implementation will ever send a CCS first in this scenario, so why am I
>     required by the spec to ignore it and implement the extra complexity in
>     TLSv1.2 handling?
> 
>     In reality I wouldn't bother to implement this which would make me
>     technically non-compliant. I would prefer it if the wording were fixed
>     to not require this.
> 
> 
> OK, I understand your point now, I think it's fine to reject this case
> as long as
> you properly handle things in the stateless case. If you want to submit
> a PR,
> I will take a look.

https://github.com/tlswg/tls13-spec/pull/1129

Matt

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