RFC 6212

Authentication-Results Registration for Vouch by Reference Results 🎀

Okay bestie, this is RFC 6212 💖 It's an Internet Standards Track document, so it's the real deal. M. Kucherawy wrote it at Cloudmark, Inc. in April 2011, and it came out of the IETF (Internet Engineering Task Force) 🦋 The ISSN is 2070-1721. The header has no Obsoletes or Updates line, but the abstract says it updates the registry of properties in Authentication-Results: message header fields ✨

Abstract

This memo updates the Authentication-Results: message header field's properties registry so you can relay the results of a Vouch By Reference query 💅

Status of This Memo

This is an Internet Standards Track document, so it's official 💅 It's a product of the IETF, and it represents the consensus of the IETF community. It went through public review and got approved for publication by the Internet Engineering Steering Group (IESG) 🫶 If you want more info on Internet Standards, check Section 2 of RFC 5741 📚

For the current status, any errata, and how to give feedback, go to http://www.rfc-editor.org/info/rfc6212 🌸

Copyright Notice

Copyright (c) 2011 IETF Trust and the persons identified as the document authors. All rights reserved 💜

This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) as they were in effect on the date of publication. Please read these carefully, because they describe your rights and restrictions for this document 🙈 Any Code Components pulled out of this document must include Simplified BSD License text, as described in Section 4.e of the Trust Legal Provisions, and they come without warranty, as described in the Simplified BSD License ⭐

Table of Contents 🗂️

1. Introduction ....................................................2
2. Keywords ........................................................2
3. Discussion ......................................................2
4. Definition ......................................................3
5. IANA Considerations .............................................4
6. Security Considerations .........................................5
7. References ......................................................5
   7.1. Normative References .......................................5
   7.2. Informative References .....................................5
Appendix A.  Authentication-Results Examples .......................6
  A.1.  VBR Results ................................................6
Appendix B.  Acknowledgements ......................................7

1. Introduction ✨

Okay so [AUTHRES] created a brand-new header field for email messages that shows the results of a message authentication check in a machine-readable format 🤖 Meanwhile, a proposal for basic domain-level reputation called Vouch By Reference, [VBR], was published, and it's now getting really popular 🔥

So this memo registers one more reporting property. It lets a VBR result get relayed as an annotation in a message header 💖

2. Keywords 🔑

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [KEYWORDS] 📖

3. Discussion 💬

Vouch By Reference [VBR] brought in a mechanism where a message receiver can ask a "vouching" service whether a trusted third party is willing to say that mail from a certain source is legitimate 🦋 When this check happens at an inbound border mail gateway, it's super useful to pass the result along to internal mail entities, like filters or user agents 🎀

What reactions to an Authentication-Results header field that has VBR (or any) results should look like is not specified here. That's entirely a matter of local policy at the receiver, so it's the receiver's call 💅

4. Definition 📝

This memo adds the following to the "Email Authentication Methods" registry, which IANA created when [AUTHRES] was published:

• The method "vbr"; and
• Associated with that method, the properties (reporting items) "header.md" and "header.mv".

If "header.md" is present, its value MUST be the DNS domain name about which a VBR query was made. If "header.mv" is present, its value MUST be the DNS domain name that was queried as the potential voucher for the "header.md" domain 💜

If the VBR query was made based on the content of a "VBR-Info" header field on an incoming message, then "header.md" is typically taken from the "md" tag of that "VBR-Info" header field, and "header.mv" is typically one of the values of the "mv" tag in that same "VBR-Info" header field 🌸 However, [VBR] allows a different mechanism for picking the subject domain and/or the list of vouchers, ignoring any "VBR-Info" header field the message might have included 👑 A server could even run a VBR query when there's no "VBR-Info" field at all, based on locally configured policy options 🧚 Whenever any of these mechanisms is used, the verifying server MAY generate an Authentication-Results field to relay the results of the VBR query ✨

This memo also adds the following result codes and definitions to the "Email Authentication Result Names" registry:

• none: No valid VBR-Info header was found in the message, or a domain name to be queried could not be determined.
• pass: A VBR query was completed, and the vouching service queried gave a positive response. 🫶
• fail: A VBR query was completed, and the vouching service queried did not give a positive response, or the message contained multiple VBR-Info header fields with different "mc" values (see [VBR]). 💀
• temperror: A VBR query was attempted but could not be completed due to some error that is likely transient in nature, such as a temporary DNS error. A later attempt may produce a final result. ⏳
• permerror: A VBR query was attempted but could not be completed due to some error that is likely not transient in nature, such as a permanent DNS error. A later attempt is unlikely to produce a final result. 🥀

Author's Address ✨

okay so this is where we find out who wrote the whole thing 💅 the contact deets are right here, bestie:

Murray S. Kucherawy
Cloudmark, Inc.
128 King St., 2nd Floor
San Francisco, CA  94107
US

Phone: +1 415 946 3800
EMail: msk@cloudmark.com

so that's Murray S. Kucherawy at Cloudmark, Inc. 🦋 if you ever need to reach out about this doc, the phone and email are right there 📞✉️

reminder: this is the last bit of the RFC, so we've officially made it through the whole thing 🎀👑

that's the whole doc, slay 🌈💖