Re: [TLS] I-D Action: draft-ietf-tls-grease-02.txt

[Martin Thomson <[e-mail]>]

On Fri, Jan 18, 2019, at 07:23, David Benjamin wrote:
> > while record_size_limit extension sends just one value, it does
> > specifically
> > allow the client to advertise higher values than the protocol versions or
> > extensions would indicate
> >
> > I wonder if sending such values shouldn't be part of GREASE behaviour,
> > even if
> > it wouldn't use GREASE values...
> >
> 
> I think that should be sorted out in a separate document. This one's been
> sitting around for a while as it is, and record_size_limit doesn't have an
> RFC to cite yet. :-)

I'm in two minds about this.  On the one hand, we don't need any actual machinery here, so why do anything?  On the other hand, it's just a note that this is possible, and adding that sort of note is easy.

> The record_size_limit extension {{!RFC8449}} includes a value that can be greased by endpoints that don't place constraints on their record size.  Advertising values larger than the protocol supports is permitted and has no effect on the behavior of a compliant peer.