Re: [DNSOP] Should root-servers.net be signed

"George Barwood" <george.barwood@blueyonder.co.uk> Fri, 19 March 2010 16:10 UTC

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From: George Barwood <george.barwood@blueyonder.co.uk>
To: Nicholas Weaver <nweaver@ICSI.Berkeley.EDU>
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Date: Fri, 19 Mar 2010 16:10:01 -0000
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Cc: dnsop@ietf.org, Nicholas Weaver <nweaver@ICSI.Berkeley.EDU>
Subject: Re: [DNSOP] Should root-servers.net be signed
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>> It cuts the response from 4K to 1.5K, and I think fragmentation that contributes
>> to these attacks being damaging.

> All I need to do is find a set of open resolvers which don't have such limits to do juuust fine.  

Eventually the open resolvers will get updated, and thus these attacks will be effectively limited.
I don't think anyone has conclusively proved they are not a risk.

> Actually, this doesn't apply, since the reason why ns.se is 2700B is all the RRSIGs in the additional section, which are after the A and AAAA records.  So spoofing this part of the datagrams is pointless anyway, since that only has meaning if DNSSEC validation IS performed.

Hold on - can't the spoofer can put whatever he likes in the fragment!? He is not limited to RRSIGs.

George