Re: [TLS] consensus on backwards compatibility changes

Kurt Roeckx <kurt@roeckx.be> Sun, 25 January 2015 20:03 UTC

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Date: Sun, 25 Jan 2015 21:03:27 +0100
From: Kurt Roeckx <kurt@roeckx.be>
To: Dave Garrett <davemgarrett@gmail.com>
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Subject: Re: [TLS] consensus on backwards compatibility changes
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On Tue, Dec 30, 2014 at 05:03:03AM -0500, Dave Garrett wrote:
> PR #105 remove SSL 2 backwards compatibility section & prohibit SSL negotiation
> https://github.com/tlswg/tls13-spec/pull/105

I have a small problem with it.  It says:
| Implementations MUST NOT send an SSL version 2.0 compatible CLIENT-HELLO.
| Implementations MUST NOT negotiate TLS 1.3 or later using an SSL version 2.0 compatible
| CLIENT-HELLO. Implementations MAY accept an SSL version 2.0 compatible CLIENT-HELLO in
| order to negotiate older versions of TLS, however this is not recommended.
| Implementations MUST NOT send or accept any records with a version less than { 3, 0 }.

Doesn't that "or accept" prevent the previous sentence?  And isn't
the rest already covered by the first sentence?


Kurt