Re: [TLS] Finished stuffing/PSK Binders

Ilari Liusvaara <ilariliusvaara@welho.com> Wed, 12 October 2016 15:45 UTC

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Date: Wed, 12 Oct 2016 18:45:23 +0300
From: Ilari Liusvaara <ilariliusvaara@welho.com>
To: Benjamin Kaduk <bkaduk@akamai.com>
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Subject: Re: [TLS] Finished stuffing/PSK Binders
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On Wed, Oct 12, 2016 at 10:13:57AM -0500, Benjamin Kaduk wrote:
> On 10/12/2016 09:27 AM, Ilari Liusvaara wrote:
> > On Wed, Oct 12, 2016 at 09:43:05PM +1100, Martin Thomson wrote:
> 
> > That would waste a bit of space with extensions signaling support
> > for some rewrites if the server doesn't use those but retries the
> > handshake.
> >
> 
> I'm having trouble parsing this.  The idea is that the client would
> waste some space in the new CH because the server doesn't have a way to
> indicate that the client only needs to send a subset of what it sent the
> first time around?

Well, depends on the extension...

Actually, not a major issue, given that there is usually a great amount
of bloat in the second CH (just to make it look like CH, instead of
just transporting what is needed).


-Ilari