Using Multiple Signing Algorithms with the ARC (Authenticated Received Chain) Protocol
draft-ietf-dmarc-arc-multi-00
The information below is for an old version of the document.
| Document | Type |
This is an older version of an Internet-Draft whose latest revision state is "Expired".
|
|
|---|---|---|---|
| Authors | Kurt Andersen , Seth Blank , John R. Levine | ||
| Last updated | 2018-01-22 | ||
| RFC stream | Internet Engineering Task Force (IETF) | ||
| Formats | |||
| Additional resources | Mailing list discussion | ||
| Stream | WG state | WG Document | |
| Document shepherd | (None) | ||
| IESG | IESG state | I-D Exists | |
| Consensus boilerplate | Unknown | ||
| Telechat date | (None) | ||
| Responsible AD | (None) | ||
| Send notices to | (None) |
draft-ietf-dmarc-arc-multi-00
DMARC Working Group K. Andersen
Internet-Draft LinkedIn
Intended status: Experimental S. Blank, Ed.
Expires: July 26, 2018 ValiMail
J. Levine, Ed.
Taughannock Networks
January 22, 2018
Using Multiple Signing Algorithms with the ARC (Authenticated Received
Chain) Protocol
draft-ietf-dmarc-arc-multi-00
Abstract
The Authenticated Received Chain (ARC) protocol creates a mechanism
whereby a series of handlers of an email message can conduct
authentication of the email message as it passes among them on the
way to its destination.
Initial development of ARC has been done with a single allowed
signing algorithm, but parallel work in the DCRUP working group
(https://datatracker.ietf.org/wg/dcrup/about/) is expanding the
supported algorithms. This specification defines how to extend ARC
for multiple signing algorithms.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on July 26, 2018.
Copyright Notice
Copyright (c) 2018 IETF Trust and the persons identified as the
document authors. All rights reserved.
Andersen, et al. Expires July 26, 2018 [Page 1]
Internet-Draft ARC-Multi January 2018
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Definitions and Terminology . . . . . . . . . . . . . . . . . 3
4. Supporting Alternate Signing Algorithms . . . . . . . . . . . 3
5. General Approach . . . . . . . . . . . . . . . . . . . . . . 3
5.1. Signers . . . . . . . . . . . . . . . . . . . . . . . . . 3
5.2. Validators . . . . . . . . . . . . . . . . . . . . . . . 3
6. Phases of Algorithm Evolution . . . . . . . . . . . . . . . . 3
6.1. Introductory Period . . . . . . . . . . . . . . . . . . . 3
6.2. Co-Existence Period . . . . . . . . . . . . . . . . . . . 4
6.3. Deprecation Period . . . . . . . . . . . . . . . . . . . 4
6.4. Obsolescence Period . . . . . . . . . . . . . . . . . . . 4
7. Privacy Considerations . . . . . . . . . . . . . . . . . . . 4
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 4
9. Security Considerations . . . . . . . . . . . . . . . . . . . 4
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 4
10.1. Normative References . . . . . . . . . . . . . . . . . . 4
10.2. Informative References . . . . . . . . . . . . . . . . . 6
Appendix A. Acknowledgements . . . . . . . . . . . . . . . . . . 7
Appendix B. Comments and Feedback . . . . . . . . . . . . . . . 7
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 7
1. Introduction
The Authenticated Received Chain (ARC) protocol adds a traceable
chain of signatures that cover the handling of an email message
through a chain of intermediary handlers.
Initial development of ARC has been done with a single allowed
signing algorithm, but parallel work in the DCRUP working group
(https://datatracker.ietf.org/wg/dcrup/about/) is expanding the
supported algorithms. This specification defines how to extend ARC
for multiple signing algorithms.
Andersen, et al. Expires July 26, 2018 [Page 2]
Internet-Draft ARC-Multi January 2018
2. Overview
In order to phase in new signing algorithms, this specification
identifies how signers and validators MUST process ARC sets found in
email messages.
3. Definitions and Terminology
This section defines terms used in the rest of the document.
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 [RFC2119].
Because many of the core concepts and definitions are found in
[RFC5598], readers SHOULD to be familiar with the contents of
[RFC5598], and in particular, the potential roles of intermediaries
in the delivery of email.
4. Supporting Alternate Signing Algorithms
During a period where multiple algorithms are allowed, all of the
statements in the ARC spec which refer to "exactly one set of ARC
headers per instance" need to be understood as "at least one set per
instance and no more than one set per instance per algorithm".
5. General Approach
5.1. Signers
Signers MUST initiate ARC signing of messages with all supported
algorithms that they are capable of using.
Signers MUST continue ARC chains with all supported algorithms that
they are capable of using.
5.2. Validators
Validators MUST use the longest ARC chain on the message for which
they can interpret the signing algorithm.
6. Phases of Algorithm Evolution
6.1. Introductory Period
Intermediaries MUST be able to validate ARC chains built with either
algorithm but MAY create ARC sets with either (or both) algorithm.
Andersen, et al. Expires July 26, 2018 [Page 3]
Internet-Draft ARC-Multi January 2018
The introductory period should be at least six (6) months.
6.2. Co-Existence Period
Intermediaries MUST be able to validate ARC chains build with either
algorithm and MUST create ARC sets with both algorithms. Chains
ending with either algorithm may be used for the result.
6.3. Deprecation Period
ARC sets built with algorithms that are being deprecated MAY be
considered valid within an ARC chain, however, intermediaries MUST
NOT create additional sets with the deprecated algorithm.
The deprecation period should be at least two (2) years.
6.4. Obsolescence Period
ARC sets built with algorithms that are obsolete MUST NOT be
considered valid within an ARC chain. Intermediaries MUST NOT create
any sets with any obsoleted algorithm.
7. Privacy Considerations
No unique privacy considerations are introduced by this specification
beyond those of the base [ARC-DRAFT-11] protocol.
8. IANA Considerations
No new IANA considerations are introduced by this specification.
9. Security Considerations
No new security considerations are introduced by this specification
beyond those of the base [ARC-DRAFT-11] protocol.
10. References
10.1. Normative References
[RFC1345] Simonsen, K., "Character Mnemonics and Character Sets",
RFC 1345, DOI 10.17487/RFC1345, June 1992,
<https://www.rfc-editor.org/info/rfc1345>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
Andersen, et al. Expires July 26, 2018 [Page 4]
Internet-Draft ARC-Multi January 2018
[RFC2142] Crocker, D., "Mailbox Names for Common Services, Roles and
Functions", RFC 2142, DOI 10.17487/RFC2142, May 1997,
<https://www.rfc-editor.org/info/rfc2142>.
[RFC2606] Eastlake 3rd, D. and A. Panitz, "Reserved Top Level DNS
Names", BCP 32, RFC 2606, DOI 10.17487/RFC2606, June 1999,
<https://www.rfc-editor.org/info/rfc2606>.
[RFC3463] Vaudreuil, G., "Enhanced Mail System Status Codes",
RFC 3463, DOI 10.17487/RFC3463, January 2003,
<https://www.rfc-editor.org/info/rfc3463>.
[RFC4686] Fenton, J., "Analysis of Threats Motivating DomainKeys
Identified Mail (DKIM)", RFC 4686, DOI 10.17487/RFC4686,
September 2006, <https://www.rfc-editor.org/info/rfc4686>.
[RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an
IANA Considerations Section in RFCs", RFC 5226,
DOI 10.17487/RFC5226, May 2008,
<https://www.rfc-editor.org/info/rfc5226>.
[RFC5234] Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax
Specifications: ABNF", STD 68, RFC 5234,
DOI 10.17487/RFC5234, January 2008,
<https://www.rfc-editor.org/info/rfc5234>.
[RFC5321] Klensin, J., "Simple Mail Transfer Protocol", RFC 5321,
DOI 10.17487/RFC5321, October 2008,
<https://www.rfc-editor.org/info/rfc5321>.
[RFC5322] Resnick, P., Ed., "Internet Message Format", RFC 5322,
DOI 10.17487/RFC5322, October 2008,
<https://www.rfc-editor.org/info/rfc5322>.
[RFC5585] Hansen, T., Crocker, D., and P. Hallam-Baker, "DomainKeys
Identified Mail (DKIM) Service Overview", RFC 5585,
DOI 10.17487/RFC5585, July 2009,
<https://www.rfc-editor.org/info/rfc5585>.
[RFC5598] Crocker, D., "Internet Mail Architecture", RFC 5598,
DOI 10.17487/RFC5598, July 2009,
<https://www.rfc-editor.org/info/rfc5598>.
[RFC5863] Hansen, T., Siegel, E., Hallam-Baker, P., and D. Crocker,
"DomainKeys Identified Mail (DKIM) Development,
Deployment, and Operations", RFC 5863,
DOI 10.17487/RFC5863, May 2010,
<https://www.rfc-editor.org/info/rfc5863>.
Andersen, et al. Expires July 26, 2018 [Page 5]
Internet-Draft ARC-Multi January 2018
[RFC6376] Crocker, D., Ed., Hansen, T., Ed., and M. Kucherawy, Ed.,
"DomainKeys Identified Mail (DKIM) Signatures", STD 76,
RFC 6376, DOI 10.17487/RFC6376, September 2011,
<https://www.rfc-editor.org/info/rfc6376>.
[RFC6377] Kucherawy, M., "DomainKeys Identified Mail (DKIM) and
Mailing Lists", BCP 167, RFC 6377, DOI 10.17487/RFC6377,
September 2011, <https://www.rfc-editor.org/info/rfc6377>.
[RFC6651] Kucherawy, M., "Extensions to DomainKeys Identified Mail
(DKIM) for Failure Reporting", RFC 6651,
DOI 10.17487/RFC6651, June 2012,
<https://www.rfc-editor.org/info/rfc6651>.
[RFC7208] Kitterman, S., "Sender Policy Framework (SPF) for
Authorizing Use of Domains in Email, Version 1", RFC 7208,
DOI 10.17487/RFC7208, April 2014,
<https://www.rfc-editor.org/info/rfc7208>.
[RFC7601] Kucherawy, M., "Message Header Field for Indicating
Message Authentication Status", RFC 7601,
DOI 10.17487/RFC7601, August 2015,
<https://www.rfc-editor.org/info/rfc7601>.
10.2. Informative References
[ARC-DRAFT-11]
Andersen, K., Long, B., and S. Jones, "Authenticated
Received Chain (ARC) Protocol (I-D-11)", n.d.,
<https://tools.ietf.org/html/
draft-ietf-dmarc-arc-protocol-11>.
[ENHANCED-STATUS]
"IANA SMTP Enhanced Status Codes", n.d.,
<http://www.iana.org/assignments/smtp-enhanced-status-
codes/smtp-enhanced-status-codes.xhtml>.
[RFC6982] Sheffer, Y. and A. Farrel, "Improving Awareness of Running
Code: The Implementation Status Section", RFC 6982,
DOI 10.17487/RFC6982, July 2013,
<https://www.rfc-editor.org/info/rfc6982>.
[RFC7489] Kucherawy, M., Ed. and E. Zwicky, Ed., "Domain-based
Message Authentication, Reporting, and Conformance
(DMARC)", RFC 7489, DOI 10.17487/RFC7489, March 2015,
<https://www.rfc-editor.org/info/rfc7489>.
Andersen, et al. Expires July 26, 2018 [Page 6]
Internet-Draft ARC-Multi January 2018
[RFC7960] Martin, F., Ed., Lear, E., Ed., Draegen. Ed., T., Zwicky,
E., Ed., and K. Andersen, Ed., "Interoperability Issues
between Domain-based Message Authentication, Reporting,
and Conformance (DMARC) and Indirect Email Flows",
RFC 7960, DOI 10.17487/RFC7960, September 2016,
<https://www.rfc-editor.org/info/rfc7960>.
10.3. URIs
[1] mailto:dmarc@ietf.org
Appendix A. Acknowledgements
This draft is the work of DMARC Working Group.
Grateful appreciation is extended to the people who provided feedback
through the discuss mailing list.
Appendix B. Comments and Feedback
Please address all comments, discussions, and questions to
dmarc@ietf.org [1].
Authors' Addresses
Kurt Andersen
LinkedIn
1000 West Maude Ave
Sunnyvale, California 94085
US
Email: kurta@linkedin.com
Seth Blank (editor)
ValiMail
Montgomery
San Francisco
US
Email: seth@valimail.com
Andersen, et al. Expires July 26, 2018 [Page 7]
Internet-Draft ARC-Multi January 2018
John Levine (editor)
Taughannock Networks
PO Box 727
Trumansburg
US
Email: standards@taugh.com
Andersen, et al. Expires July 26, 2018 [Page 8]