[dmarc-ietf] Tree Walk + CNAME
"Brotman, Alex" <Alex_Brotman@comcast.com> Wed, 30 March 2022 12:49 UTC
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From: "Brotman, Alex" <Alex_Brotman@comcast.com>
To: "dmarc@ietf.org" <dmarc@ietf.org>
Thread-Topic: Tree Walk + CNAME
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Date: Wed, 30 Mar 2022 12:49:18 +0000
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Archived-At: <https://mailarchive.ietf.org/arch/msg/dmarc/g99KQ7Q8zltDEg0KiGBIdzgQRXs>
Subject: [dmarc-ietf] Tree Walk + CNAME
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>From section 4.6: To illustrate, for a message with the arbitrary RFC5322.From domain of "a.b.c.d.e.mail.example.com", a full DNS Tree Walk would require the following five queries, in order to locate the policy or Organizational Domain: * _dmarc.a.b.c.d.e.mail.example.com * _dmarc.e.mail.example.com * _dmarc.mail.example.com * _dmarc.example.com * _dmarc.com What should the evaluator do if one of these results in a CNAME that either: a) points outside of the tree b) results in a loop pointing at a previously evaluated record -- Alex Brotman Sr. Engineer, Anti-Abuse & Messaging Policy Comcast
- [dmarc-ietf] Tree Walk + CNAME Brotman, Alex
- Re: [dmarc-ietf] Tree Walk + CNAME Tim Wicinski
- Re: [dmarc-ietf] Tree Walk + CNAME John Levine
- Re: [dmarc-ietf] Tree Walk + CNAME Scott Kitterman