Subject: [dmarc-ietf] New Version of draft-levine-dbound-dns-03 with code

From: "John R Levine" <[email-masked]>
Date: 27 Apr 2019 15:19:57 -0400

You may recall that we've been discussing ways to publish DNS authority 
boundaries, like the Mozilla PSL but in the DNS itself, not a text file.

I've been claiming that with careful use of wildcards one make the number 
of lookups depend on the number of boundaries, not the number of labels 
in the name being checked, so it's reliably reasonably fast.

I figured I should put my bits where my mouth is so I wrote a script to 
translate the Mozilla PSL into DNS rules.  It turned out to be harder than 
I thought because the PSL has wildcard rules with exceptions, e.g.:

*.ck
!www.ck

That turned out to be straightforward to handle with a tweak to the spec I 
just made in the -03 version.

The code to make the DNS records, and another script to take a domain name 
and look it up in those records are here:

https://github.com/jrlevine/bound

I think the lookup code is OK but there may be some glitches in the PSL 
translator for some of the more arcane combination of wildcard and 
non-wildcard boundaries.  Take a look if interested.

Regards,
John Levine, [email-masked], Taughannock Networks, Trumansburg NY
Please consider the environment before reading this e-mail. https://jl.ly

PS to Scott: I think it would be pretty easy to add a tag for PSD TLDs.