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Re: [TLS] Record header size?

Eric Rescorla <ekr@rtfm.com> Tue, 17 November 2015 20:51 UTC

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From: Eric Rescorla <ekr@rtfm.com>
Date: Tue, 17 Nov 2015 12:50:28 -0800
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To: Daniel Kahn Gillmor <dkg@fifthhorseman.net>
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Subject: Re: [TLS] Record header size?
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Indeed. It doesn't seem useful to carry around two fixed bytes
for alignment reasons

-Ekr


On Tue, Nov 17, 2015 at 12:45 PM, Daniel Kahn Gillmor <dkg@fifthhorseman.net
> wrote:

> On Tue 2015-11-17 12:09:30 -0500, Eric Rescorla wrote:
> > The concern here is backward compatibility with inspection middleboxes
> which
> > expect the length field to be in a particular place. We agreed in
> Seattle to
> > wait for early deployment experience before modifying the header to move
> > the length.
>
> In particular, if we're going to make a change to the TLS record header,
> the change would be to remove the version and the type entirely, leaving
> only two octets of length on each record.  Is a two-octet offset going
> to be problematic?
>
>          --dkg
>

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