Re: [DNSOP] Whiskey Tango Foxtrot on key lengths...

Tony Finch <dot@dotat.at> Fri, 28 March 2014 13:01 UTC

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Date: Fri, 28 Mar 2014 13:01:15 +0000
From: Tony Finch <dot@dotat.at>
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To: Paul Wouters <paul@nohats.ca>
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Cc: dnsop WG <dnsop@ietf.org>, Nicholas Weaver <nweaver@icsi.berkeley.edu>
Subject: Re: [DNSOP] Whiskey Tango Foxtrot on key lengths...
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Paul Wouters <paul@nohats.ca> wrote:

> On Thu, 27 Mar 2014, Nicholas Weaver wrote:
>
> > For an attacker, the root ZSK is not 1 month validity, since an attacker
> > who's in a position to take advantage of such a ZSK compromise is going to
> > be faking all of DNS for the target, and can therefore just as easily also
> > fake NTP, ensuring that the attacker's key is still valid for most victims.
>
> Than you have lost forever because we have used a 1024 key in the past.
> You can always NTP attack them to today's 1024 key, and no increase in
> key size in the future will help you.

I have a rough plan for how to avoid the insecure time replay vulnerability:
http://www.ietf.org/mail-archive/web/dnsop/current/msg11245.html

Tony.
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