Re: I-D Action: draft-west-let-localhost-be-localhost-00.txt

"John Levine" <johnl@taugh.com> Tue, 27 September 2016 18:49 UTC

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Date: 27 Sep 2016 18:48:45 -0000
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From: "John Levine" <johnl@taugh.com>
To: ietf@ietf.org
Subject: Re: I-D Action: draft-west-let-localhost-be-localhost-00.txt
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>> As this proposal is in the name of consistency, is there an argument we
>> should be strict and explicitly define *which* loopback address DNS servers
>> must return when queried?
>
>I was intentionally vague on that point, as one of the scenarios raised in
>https://github.com/w3c/webappsec-secure-contexts/issues/43 was a developer
>who was pointing `project1.localhost` to 127.0.0.1, and
>`project2.localhost` to 127.0.0.2 in /etc/hosts (and presumably had a
>server configured accordingly). It seems like that's a reasonable thing to
>support. Any loopback address is fine with me.

I use multiple IPv4 127/8 addresses all the time.  For example, I run
a funky local stunt DNS server on 127.0.1.1 and configure my local DNS
cache to use it for a branch of the name tree.  So yes, any loopback
address will do.  (We can save the question about a link-local IPv6
address on a loopback interface for later.)

R's,
John