wdiff rfc8749.alt-original rfc8749.txt

DNS Operations

Internet Engineering Task Force (IETF) W. Mekking
Internet-Draft
Request for Comments: 8749 D. Mahoney
Updates: 6698, 6840 (if approved) ISC
Intended status:
Category: Standards Track October 31, 2019
Expires: May 3, March 2020
ISSN: 2070-1721

Moving DNSSEC Lookaside Validation (DLV) to Historic Status
draft-ietf-dnsop-obsolete-dlv-02

Abstract

This document obsoletes retires DNSSEC lookaside validation Lookaside Validation (DLV) and
reclassifies RFCs 4431 and 5074 as Historic. Furthermore, this
document updates RFC 6698 by excluding the DLV resource record from
certificates,
certificates and updates RFC 6840 by excluding the DLV registries
from the trust anchor selection.

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 an Internet Standards Track document.

This document is a product of the Internet Engineering Task Force
(IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list It represents the consensus of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.

Internet-Drafts are draft documents valid the IETF community. It has
received public review and has been approved for a maximum 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 six months this document, any errata,
and how to provide feedback on it may be updated, replaced, or obsoleted by other documents obtained 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 May 3, 2020.
https://www.rfc-editor.org/info/rfc8749.

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. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 2 Requirements Language
3. Discussion . . . . . . . . . . . . . . . . . . . . . . . . . 2
4. Moving DLV to Historic Status . . . . . . . . . . . . . . . . 3
4.1. Documents that reference That Reference the DLV RFCs . . . . . . . . . . 3
4.1.1. Documents that reference That Reference RFC 4431 . . . . . . . . . . 3
4.1.2. Documents that reference That Reference RFC 5074 . . . . . . . . . . 4
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 4
6. Security considerations . . . . . . . . . . . . . . . . . . . 4 Considerations
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 5
8. Normative References . . . . . . . . . . . . . . . . . . . . 5
Acknowledgements
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 6

1. Introduction

DNSSEC Lookaside Validation (DLV) was introduced to assist with the
adoption of DNSSEC [RFC4033] [RFC4034] [RFC4035] in a time where when the
root zone and many top level top-level domains (TLDs) were unsigned, to help unsigned. DLV
allowed entities with signed zones under an unsigned parent zone, zone or that
have
entities with registrars that don't did not accept DS records. records to publish
trust anchors outside of the normal DNS delegation chain. The root
zone is was signed since in July 2010 2010, and as of May 2019, 1389 out of 1531
TLDs have a secure delegation from the root; thus thus, DLV has served its
purpose and can now retire.

2. Terminology Requirements Language

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in
BCP 14 [RFC2119] [RFC8174] when, and [RFC8174]. only when, they appear in all
capitals, as shown here.

3. Discussion

One could argue that DLV is still useful because there are still some
unsigned TLDs and entities under those zones that will not benefit
from signing their zone. However, keeping the DLV mechanism also has
disadvantages:

* It reduces the pressure to get the parent zone signed.

* It reduces the pressure on registrars to accept DS records.

* It complicates validation code.

In addition, not every validator actually implemented DLV (only BIND
9 and Unbound) Unbound), so even if an entity can use DLV to set up an
alternate path to its trust anchor, its effect is limited.
Furthermore, there was one well-known DLV registry (dlv.isc.org) and
that has been (dlv.isc.org),
which was deprecated (replaced with a signed empty zone) on September
30, 2017. With the absence of a well-known DLV registry
service service, it
is unlikely that there is a real benefit for the protocol on the
Internet nowadays.

One other possible reason to keep DLV is to distribute trust anchors
for private enterprises. There are no known uses of DLV for this.

All things considered considered, it is probably not worth the effort of
maintaining the DLV mechanism.

4. Moving DLV to Historic Status

There are two RFCs that specify DLV:

1. RFC 4431 [RFC4431] specifies the DLV resource record.

2. RFC 5074 [RFC5074] specifies the DLV mechanism for publishing
trust anchors outside the DNS delegation chain and how validators
can use them to validate DNSSEC-signed data.

This document moves both RFC 4431 [RFC4431] and RFC 5074 [RFC5074] to
Historic status. This is a clear signal to implementers that the DLV
resource record and the DLV mechanism SHOULD NOT be implemented or
deployed.

4.1. Documents that reference That Reference the DLV RFCs

The RFCs that are being moved to Historic status are referenced by a couple of
other documents. RFCs. The sections below describe what the changes
when to those
documents due to the DLV RFCs have been being reclassified as Historic.

4.1.1. Documents that reference That Reference RFC 4431

One RFC makes reference to RFC 4431 [RFC4431].

4.1.1.1. RFC 5074

RFC 5074 [RFC5074], "DNSSEC ("DNSSEC Lookaside Validation (DLV)" (DLV)") [RFC5074] describes
the DLV mechanism itself, and is being moved itself. This document moves RFC 5074 [RFC5074] to
Historic status too. as well.

4.1.2. Documents that reference That Reference RFC 5074

Three RFCs make reference to RFC 5074 [RFC5074].

4.1.2.1. RFC 6698

RFC 6698, "The 6698 ("The DNS-Based Authentication of Named Entities (DANE)
Transport Layer Security (TLS) Protocol: TLSA" TLSA") [RFC6698] specifies:

| DNSSEC forms certificates (the binding of an identity to a key) by
| combining a DNSKEY, DS, or DLV resource record with an associated
| RRSIG record. These records then form a signing chain extending
| from the client's trust anchors to the RR of interest.

This document updates RFC 6698 [RFC6698] to exclude the DLV resource
record from certificates.

4.1.2.2. RFC 6840

RFC 6840, "Clarifications 6840 ("Clarifications and Implementation Notes for DNS Security
(DNSSEC)"
(DNSSEC)") [RFC6840] says states that when trust anchors come from
different sources, a validator may choose between them based on the
perceived reliability of those sources. But in reality reality, this does
not happen in validators (both BIND 9 and Unbound have a an option for
a DLV trust anchor that can be used solely as a fallback).

This document updates RFC 6840 [RFC6840] to exclude the DLV
registries from the trust anchor selection.

4.1.2.3. RFC 8198

RFC 8198, "Aggressive 8198 ("Aggressive Use of DNSSEC-Validated Cache" Cache") [RFC8198] only
references RFC 5074 [RFC5074] because aggressive negative caching was
first proposed there.

5. IANA Considerations

IANA should update has updated the annotation of the DLV RR type (code 32769) to
"Obsolete" in the DNS Parameters "Domain Name System (DNS) Parameters" registry.

6. Security considerations

When Considerations

Once the DLV mechanism goes away, is retired, zones that rely on DLV for their
validation will be treated as insecure. The chance that this
scenario actually occurs is very low, since no well-known DLV
registry exists.

8. Normative References

[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>.

[RFC4033] Arends, R., Austein, R., Larson, M., Massey, D., and S.
Rose, "DNS Security Introduction and Requirements",
RFC 4033, DOI 10.17487/RFC4033, March 2005,
<https://www.rfc-editor.org/info/rfc4033>.

[RFC4034] Arends, R., Austein, R., Larson, M., Massey, D., and S.
Rose, "Resource Records for the DNS Security Extensions",
RFC 4034, DOI 10.17487/RFC4034, March 2005,
<https://www.rfc-editor.org/info/rfc4034>.

[RFC4035] Arends, R., Austein, R., Larson, M., Massey, D., and S.
Rose, "Protocol Modifications for the DNS Security
Extensions", RFC 4035, DOI 10.17487/RFC4035, March 2005,
<https://www.rfc-editor.org/info/rfc4035>.

[RFC4431] Andrews, M. and S. Weiler, "The DNSSEC Lookaside
Validation (DLV) DNS Resource Record", RFC 4431,
DOI 10.17487/RFC4431, February 2006,
<https://www.rfc-editor.org/info/rfc4431>.

[RFC5074] Weiler, S., "DNSSEC Lookaside Validation (DLV)", RFC 5074,
DOI 10.17487/RFC5074, November 2007,
<https://www.rfc-editor.org/info/rfc5074>.

[RFC6698] Hoffman, P. and J. Schlyter, "The DNS-Based Authentication
of Named Entities (DANE) Transport Layer Security (TLS)
Protocol: TLSA", RFC 6698, DOI 10.17487/RFC6698, August
2012, <https://www.rfc-editor.org/info/rfc6698>.

[RFC6840] Weiler, S., Ed. and D. Blacka, Ed., "Clarifications and
Implementation Notes for DNS Security (DNSSEC)", RFC 6840,
DOI 10.17487/RFC6840, February 2013,
<https://www.rfc-editor.org/info/rfc6840>.

[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.

[RFC8198] Fujiwara, K., Kato, A., and W. Kumari, "Aggressive Use of
DNSSEC-Validated Cache", RFC 8198, DOI 10.17487/RFC8198,
July 2017, <https://www.rfc-editor.org/info/rfc8198>.

Acknowledgements

Ondrej Sury

The authors thank Ondřej Surý for the initial review.

Authors' Addresses

Matthijs

W. (Matthijs) Mekking
ISC
Netherlands

Email: matthijs@isc.org

Dan Mahoney
ISC
950 Charter St
Redwood City, CA 94063
USA
United States of America

Email: dmahoney@isc.org