[TLS] explicitly specify ClientHello record version

[Dave Garrett <[e-mail]>]

On Tuesday, December 23, 2014 04:51:40 pm Brian Smith wrote:
> I think further changes can be made to tighten up the text regarding
> allowed record versions, but those changes are more open for debate.
> For example, we might say that the ClientHello's record version MUST
> be { 3, 1 } and that the version field in all other records MUST equal
> the negotiated version. But, again, this can be done on top of your
> changes.

Making the revisions for that was straightforward enough. I've also made some 
small editorial changes to the backwards compatibility section to update things 
as well as make it a little easier to follow.

https://github.com/tlswg/tls13-spec/pull/107

That plus the other PR for dealing with SSL should probably be enough to resolve 
issue #54, "Rewrite backward compatibility section to deal with TLS 1.3".

I'm no expert on the implementation details of working with buggy severs, so it 
might be warranted to add more information here.

I know some implementations already specify the ClientHello in this fashion, yet 
I don't know if there's a consensus on this topic. I would expect to wait until 
next year for those who wish to debate this, due to the holiday season.


Dave