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Re: [DNSOP] Clarification question: compression pointers always to names earlier in the packet?

Mark Andrews <marka@isc.org> Wed, 24 October 2018 20:10 UTC

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From: Mark Andrews <marka@isc.org>
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Date: Thu, 25 Oct 2018 07:10:14 +1100
Cc: martin@opennetlabs.com, Tony Finch <dot@dotat.at>, dnsop WG <dnsop@ietf.org>
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References: <BC2CDF40-4FF0-4111-88B7-04969491D2E0@dukhovni.org> <alpine.DEB.2.20.1810241135130.24450@grey.csi.cam.ac.uk> <20181024124831.610d7521@glaurung.nlnetlabs.nl> <CAPt1N1=r2fMs8UJh9eM6BZHYXEwJgYzKDVqs5J7MZhS1n5Zx6A@mail.gmail.com>
To: Ted Lemon <mellon@fugue.com>
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Subject: Re: [DNSOP] Clarification question: compression pointers always to names earlier in the packet?
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No.

> On 25 Oct 2018, at 6:52 am, Ted Lemon <mellon@fugue.com> wrote:
> 
> Is there ever a valid reason to have a pointer to a pointer, though?   This is dead easy to detect.
> 
> On Wed, Oct 24, 2018 at 6:48 AM Martin Hoffmann <martin@opennetlabs.com> wrote:
> Tony Finch wrote:
> > 
> > Note that limiting the overall length of the name isn't enough,
> > because a pointer can loop without making the name longer.
> 
> You are, of course, right.
> 
> Kind regards,
> Martin
> 
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Mark Andrews, ISC
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