[TLS] Clarification of valid_time validation checks in tls-subcerts document

Luke Valenta <lvalenta@cloudflare.com> Fri, 02 April 2021 20:59 UTC

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From: Luke Valenta <lvalenta@cloudflare.com>
Date: Fri, 2 Apr 2021 15:59:17 -0500
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Subject: [TLS] Clarification of valid_time validation checks in tls-subcerts document
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Hi folks,

I have a PR at https://github.com/tlswg/tls-subcerts/pull/83 to clarify
some text in the tls-subcert document regarding client-side validation with
respect to valid_time.

Below is a quick summary of the changes:
- Clarify in valid_time definition that validation happens with respect to
the current time (Rich Salz made a similar suggestion at
https://mailarchive.ietf.org/arch/msg/tls/026iVah93ZXZ02pUq3thyjlhnSs/)
- Correct and clarify client-side validation steps described at
https://tools.ietf.org/html/draft-ietf-tls-subcerts-10#section-4.1.3; Step
1 and 3 were previously incorrect or ambiguous, and step 2 has been
clarified.

Please take a look and leave comments if you have any!

-- 
Luke Valenta
Systems Engineer - Research