Re: [DNSOP] Status of "let localhost be localhost"?

Jacob Hoffman-Andrews <> Wed, 02 August 2017 21:06 UTC

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To: Matthew Pounsett <>
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From: Jacob Hoffman-Andrews <>
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Date: Wed, 2 Aug 2017 14:06:20 -0700
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Subject: Re: [DNSOP] Status of "let localhost be localhost"?
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On 08/02/2017 12:09 PM, Matthew Pounsett wrote:
> In the case where 'localhost' is being passed to DNS resolution
> software, a validating stub (for example inside a web browser)
Ah, this may be where we are finding a disconnect. I believe web
browsers never operate validating stub resolvers, but generally ask the
operating system resolver library. Do you have a counter-example?

I think it's also rare for operating system resolver libraries to
validate DNSSEC (rather than leaving it to an upstream recursive
resolver). However, even if we take it as a given that operating system
stub resolvers should implement DNSSEC validation, they clearly already
treat localhost specially, so there is no reason to believe that they
would start trying to validate it with DNSSEC once this document is