Internet Engineering Task Force (IETF) D. Crocker, Ed.
Request for Comments: 6376 Brandenburg InternetWorking
Obsoletes: 4871, 5672 T. Hansen, Ed.
Category: Standards Track AT&T Laboratories
ISSN: 2070-1721 M. Kucherawy, Ed.
Cloudmark
September 2011
DomainKeys Identified Mail (DKIM) Signatures
Abstract
DomainKeys Identified Mail (DKIM) permits a person, role, or
organization that owns the signing domain to claim some
responsibility for a message by associating the domain with the
message. This can be an author's organization, an operational relay,
or one of their agents. DKIM separates the question of the identity
of the Signer of the message from the purported author of the
message. Assertion of responsibility is validated through a
cryptographic signature and by querying the Signer's domain directly
to retrieve the appropriate public key. Message transit from author
to recipient is through relays that typically make no substantive
change to the message content and thus preserve the DKIM signature.
This memo obsoletes RFC 4871 and RFC 5672.
Status of This Memo
This is an Internet Standards Track document.
This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 5741.
Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
http://www.rfc-editor.org/info/rfc6376.
Copyright Notice
Copyright (c) 2011 IETF Trust and the persons identified as the
document authors. All rights reserved.
Crocker, et al. Standards Track [Page 1]
RFC 6376 DKIM Signatures September 2011
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.1. DKIM Architecture Documents . . . . . . . . . . . . . . . 5
1.2. Signing Identity . . . . . . . . . . . . . . . . . . . . . 5
1.3. Scalability . . . . . . . . . . . . . . . . . . . . . . . 5
1.4. Simple Key Management . . . . . . . . . . . . . . . . . . 6
1.5. Data Integrity . . . . . . . . . . . . . . . . . . . . . . 6
2. Terminology and Definitions . . . . . . . . . . . . . . . . . 6
2.1. Signers . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.2. Verifiers . . . . . . . . . . . . . . . . . . . . . . . . 7
2.3. Identity . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.4. Identifier . . . . . . . . . . . . . . . . . . . . . . . . 7
2.5. Signing Domain Identifier (SDID) . . . . . . . . . . . . . 7
2.6. Agent or User Identifier (AUID) . . . . . . . . . . . . . 7
2.7. Identity Assessor . . . . . . . . . . . . . . . . . . . . 7
2.8. Whitespace . . . . . . . . . . . . . . . . . . . . . . . . 8
2.9. Imported ABNF Tokens . . . . . . . . . . . . . . . . . . . 8
2.10. Common ABNF Tokens . . . . . . . . . . . . . . . . . . . . 9
2.11. DKIM-Quoted-Printable . . . . . . . . . . . . . . . . . . 9
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