RFC 9373 PROPOSED STANDARD DNS · IPSEC · EDDSA
EdDSA for IPSECKEY: EdDSA Value for IPSECKEY
Registers a value so EdDSA public keys can be stored in IPSECKEY DNS records.
RFC EDITOR
Moskowitz, R., Kivinen, T., and M. Richardson, "EdDSA Value for IPSECKEY", RFC 9373, DOI 10.17487/RFC9373, March 2023, <https://www.rfc-editor.org/info/rfc9373>.
BIBTEX
@misc{rfc9373,
series = {Request for Comments},
number = 9373,
howpublished = {RFC 9373},
publisher = {RFC Editor},
doi = {10.17487/RFC9373},
url = {https://www.rfc-editor.org/info/rfc9373},
author = {R. Moskowitz and T. Kivinen and M. Richardson},
title = {{EdDSA Value for IPSECKEY}},
pagetotal = 5,
year = 2023,
month = mar,
} RFC text
Contents
Internet Engineering Task Force (IETF) R. Moskowitz
Request for Comments: 9373 HTT Consulting
Category: Standards Track T. Kivinen
ISSN: 2070-1721
M. Richardson
Sandelman
March 2023
EdDSA Value for IPSECKEY
Abstract
This document assigns a value for Edwards-Curve Digital Signature
Algorithm (EdDSA) Public Keys to the "IPSECKEY Resource Record
Parameters" registry.
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 7841.
Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
https://www.rfc-editor.org/info/rfc9373.
Copyright Notice
Copyright (c) 2023 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
(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 Revised BSD License text as described in Section 4.e of the
Trust Legal Provisions and are provided without warranty as described
in the Revised BSD License.
Table of Contents
1. Introduction
2. IPSECKEY Support for EdDSA
3. IANA Considerations
3.1. Update to the IANA IPSECKEY Registry
3.1.1. Reformat the Algorithm Type Field Registry
3.1.2. Add to the Algorithm Type Field Registry
4. Security Considerations
5. References
5.1. Normative References
5.2. Informative References
Appendix A. IPSECKEY EdDSA Example
Acknowledgments
Authors' Addresses
1. Introduction
IPSECKEY [RFC4025] is a resource record (RR) for the Domain Name
System (DNS) that is used to store public keys for use in IP security
(IPsec) systems. The IPSECKEY RR relies on the IPSECKEY "Algorithm
Type Field" registry [IANA-IPSECKEY] to enumerate the permissible
formats for the public keys.
This document adds support for Edwards-Curve Digital Security
Algorithm (EdDSA) public keys in the format defined in [RFC8080] to
the IPSECKEY RR.
2. IPSECKEY Support for EdDSA
When using the EdDSA public key in the IPSECKEY RR, the value 4 is
used as an algorithm and the public key is formatted as specified in
"Edwards-Curve Digital Security Algorithm (EdDSA) for DNSSEC"
(Section 3 of [RFC8080]).
+=======+=====================+======================+===========+
| Value | Description | Format Description | Reference |
+=======+=====================+======================+===========+
| 4 | An EdDSA Public Key | [RFC8080], Section 3 | This RFC |
+-------+---------------------+----------------------+-----------+
Table 1
3. IANA Considerations
3.1. Update to the IANA IPSECKEY Registry
3.1.1. Reformat the Algorithm Type Field Registry
Per this document, IANA has added the "Format Description" field to
the "Algorithm Type Field" registry of the "IPSECKEY Resource Record
Parameters" [IANA-IPSECKEY]. In addition, IANA has updated the
"Description" field in existing entries of that registry to
explicitly state that they are for "Public" keys:
+=======+==========================+====================+===========+
| Value | Description | Format Description | Reference |
+=======+==========================+====================+===========+
| 0 | No Public key | | [RFC4025] |
| | is present | | |
+-------+--------------------------+--------------------+-----------+
| 1 | A DSA Public | [RFC2536], | [RFC4025] |
| | Key | Section 2 | |
+-------+--------------------------+--------------------+-----------+
| 2 | An RSA Public | [RFC3110], | [RFC4025] |
| | Key | Section 2 | |
+-------+--------------------------+--------------------+-----------+
| 3 | An ECDSA | [RFC6605], | [RFC8005] |
| | Public Key | Section 4 | |
+-------+--------------------------+--------------------+-----------+
Table 2
IANA added a reference to this document to the "Algorithm Type Field"
registry.
3.1.2. Add to the Algorithm Type Field Registry
Further, IANA has made the following addition to the "Algorithm Type
Field" registry within the "IPSECKEY Resource Record Parameters"
[IANA-IPSECKEY]:
+=======+=====================+======================+===========+
| Value | Description | Format Description | Reference |
+=======+=====================+======================+===========+
| 4 | An EdDSA Public Key | [RFC8080], Section 3 | This RFC |
+-------+---------------------+----------------------+-----------+
Table 3
4. Security Considerations
The security considerations discussed in [RFC4025] apply. This
document does not introduce any new security considerations.
5. References
5.1. Normative References
[IANA-IPSECKEY]
IANA, "IPSECKEY Resource Record Parameters",
<https://www.iana.org/assignments/ipseckey-rr-parameters>.
[RFC8080] Sury, O. and R. Edmonds, "Edwards-Curve Digital Security
Algorithm (EdDSA) for DNSSEC", RFC 8080,
DOI 10.17487/RFC8080, February 2017,
<https://www.rfc-editor.org/info/rfc8080>.
5.2. Informative References
[RFC2536] Eastlake 3rd, D., "DSA KEYs and SIGs in the Domain Name
System (DNS)", RFC 2536, DOI 10.17487/RFC2536, March 1999,
<https://www.rfc-editor.org/info/rfc2536>.
[RFC3110] Eastlake 3rd, D., "RSA/SHA-1 SIGs and RSA KEYs in the
Domain Name System (DNS)", RFC 3110, DOI 10.17487/RFC3110,
May 2001, <https://www.rfc-editor.org/info/rfc3110>.
[RFC4025] Richardson, M., "A Method for Storing IPsec Keying
Material in DNS", RFC 4025, DOI 10.17487/RFC4025, March
2005, <https://www.rfc-editor.org/info/rfc4025>.
[RFC6605] Hoffman, P. and W.C.A. Wijngaards, "Elliptic Curve Digital
Signature Algorithm (DSA) for DNSSEC", RFC 6605,
DOI 10.17487/RFC6605, April 2012,
<https://www.rfc-editor.org/info/rfc6605>.
[RFC8005] Laganier, J., "Host Identity Protocol (HIP) Domain Name
System (DNS) Extension", RFC 8005, DOI 10.17487/RFC8005,
October 2016, <https://www.rfc-editor.org/info/rfc8005>.
Appendix A. IPSECKEY EdDSA Example
The following is an example of an IPSECKEY RR with no gateway, and an
EdDSA public key. It uses the IPSECKEY presentation format which is
base64.
foo.example.com. IN IPSECKEY (
10 0 4 . 3WTXgUvpn1RlCXnm80gGY2LZ/ErUUEZtZ33IDi8yfhM= )
The associated EdDSA private key (in hex) is as follows:
c7be71a45cbf87785f639dc4fd1c82637c21b5e02488939976ece32b9268d0b7
Acknowledgments
Thanks to the Security Area Director, Paul Wouters, for his initial
review. Also, thanks to Security Area Director, Roman Danyliw, for
his final reviews and document shepherding.
Authors' Addresses
Robert Moskowitz
HTT Consulting
Oak Park, MI 48237
United States of America
Email: rgm@labs.htt-consult.com
Tero Kivinen
Email: kivinen@iki.fi
Michael C. Richardson
Sandelman Software Works
Email: mcr+ietf@sandelman.ca
URI: https://www.sandelman.ca/
AI ELI5
On this page
PROBLEMThe IPSECKEY DNS record stores public keys for IPsec, but its Algorithm Type registry had no entry for EdDSA keys.
MECHANISMThe document assigns algorithm value 4 to an EdDSA public key, formatted as in Section 3 of RFC 8080, and reformats the registry to add a Format Description column.
WHY IT MATTERSEdDSA public keys can be published in IPSECKEY records. The document adds no new security considerations.
§1IPSECKEY and EdDSA
The IPSECKEY resource record (RFC 4025) stores public keys for IPsec systems in the DNS. It relies on the IANA "Algorithm Type Field" registry to list the permitted key formats.
This document adds EdDSA public keys, in the format defined in RFC 8080, to that list.
A DNS record can hold a key for secure connections. This says the new kind of key is allowed in it.
§2Algorithm Value 4
When an EdDSA public key is put in an IPSECKEY record, the algorithm value 4 is used and the key is formatted as in Section 3 of RFC 8080. The registry entry reads "An EdDSA Public Key".
IANA also added a Format Description field to the registry and updated existing descriptions to say they are for "Public" keys. Existing values are 0 (no public key present), 1 (DSA), 2 (RSA) and 3 (ECDSA).
The list of key types now has a number 4 for the new kind, and a new column saying where its format is described.
- 0No public key — No public key is present.
- 1DSA — A DSA public key.
- 2RSA — An RSA public key.
- 3ECDSA — An ECDSA public key.
- 4EdDSA — An EdDSA public key, formatted as in RFC 8080, Section 3.
§3Example and Security
An appendix shows an IPSECKEY record with no gateway and an EdDSA public key in base64 presentation format, plus the matching private key in hex.
The security considerations of RFC 4025 apply, and the document introduces no new ones.
The document shows a sample entry, and says this change makes nothing less safe.