Re: [DNSOP] If DNSSEC signatures do not validate ...

Shumon Huque <> Tue, 28 April 2020 13:56 UTC

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From: Shumon Huque <>
Date: Tue, 28 Apr 2020 09:56:44 -0400
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To: Davey Song <>
Cc: Paul Wouters <>, dnsop <>
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Subject: Re: [DNSOP] If DNSSEC signatures do not validate ...
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On Tue, Apr 28, 2020 at 9:48 AM Davey Song <> wrote:

> I think you mean if you receive a BOGUS validation result (eg missing
>> RRSIG records, or otherwise are not getting the records needed for proof
>> of non-existance or signatures. In that case, I think the existing
>> DNS protocol already tells you to try other servers?
> According to RFC4035 section 5.5, there is  no retry to other servers.

That language could probably use some clarification. I would interpret
"if .. none of the RRSIGs can be validated" as "if .. none of the RRSIGs
can be validated from _any_ of the authority servers". In practice, every
validating resolver I'm familiar with will retry other servers upon
validation failure. Otherwise, we would have a very fragile system - an
adversary would just have to be able to intercept one path between resolver
and one of the authority servers for a zone to cause resolution failure.