5Internet Engineering Task Force (IETF) P. Hoffman
6Request for Comments: 9157 ICANN
7Updates: 5155, 6014, 8624 November 2021
8Category: Standards Track
12 Revised IANA Considerations for DNSSEC
16 This document changes the review requirements needed to get DNSSEC
17 algorithms and resource records added to IANA registries. It updates
18 RFC 6014 to include hash algorithms for Delegation Signer (DS)
19 records and NextSECure version 3 (NSEC3) parameters (for Hashed
20 Authenticated Denial of Existence). It also updates RFCs 5155 and
21 6014, which have requirements for DNSSEC algorithms, and updates RFC
22 8624 to clarify the implementation recommendation related to the
23 algorithms described in RFCs that are not on the standards track.
24 The rationale for these changes is to bring the requirements for DS
25 records and hash algorithms used in NSEC3 in line with the
26 requirements for all other DNSSEC algorithms.
30 This is an Internet Standards Track document.
32 This document is a product of the Internet Engineering Task Force
33 (IETF). It represents the consensus of the IETF community. It has
34 received public review and has been approved for publication by the
35 Internet Engineering Steering Group (IESG). Further information on
36 Internet Standards is available in Section 2 of RFC 7841.
38 Information about the current status of this document, any errata,
39 and how to provide feedback on it may be obtained at
40 https://www.rfc-editor.org/info/rfc9157.
44 Copyright (c) 2021 IETF Trust and the persons identified as the
45 document authors. All rights reserved.
47 This document is subject to BCP 78 and the IETF Trust's Legal
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49 (https://trustee.ietf.org/license-info) in effect on the date of
50 publication of this document. Please review these documents
51 carefully, as they describe your rights and restrictions with respect
52 to this document. Code Components extracted from this document must
53 include Revised BSD License text as described in Section 4.e of the
54 Trust Legal Provisions and are provided without warranty as described
55 in the Revised BSD License.
60 1.1. Requirements Language
63 4. IANA Considerations
64 5. Security Considerations
66 6.1. Normative References
67 6.2. Informative References
73 DNSSEC is primarily described in [RFC4033], [RFC4034], and [RFC4035].
74 DNSSEC commonly uses another resource record beyond those defined in
75 [RFC4034]: NSEC3 [RFC5155]. DS resource records were originally
76 defined in [RFC3658], and that definition was obsoleted by [RFC4034].
78 [RFC6014] updates the requirements for how DNSSEC cryptographic
79 algorithm identifiers in the IANA registries are assigned, reducing
80 the requirements from "Standards Action" to "RFC Required". However,
81 the IANA registry requirements for hash algorithms for DS records
82 [RFC3658] and for the hash algorithms used in NSEC3 records [RFC5155]
83 are still "Standards Action". This document updates those IANA
84 registry requirements. (For a reference on how IANA registries can
85 be updated in general, see [RFC8126].)
871.1. Requirements Language
89 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
90 "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
91 "OPTIONAL" in this document are to be interpreted as described in
92 BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
93 capitals, as shown here.
97 Section 4 updates [RFC6014] to bring the requirements for DS records
98 and NSEC3 hash algorithms in line with the rest of the DNSSEC
99 cryptographic algorithms by allowing any DS hash algorithms, NSEC3
100 hash algorithms, NSEC3 parameters, and NSEC3 flags that are fully
101 described in an RFC to have identifiers assigned in the IANA
102 registries. This is an addition to the IANA considerations in
107 This document updates [RFC8624] for all DNSKEY and DS algorithms that
108 are not on the standards track.
110 The second paragraph of Section 1.2 of [RFC8624] currently says:
112 | This document only provides recommendations with respect to
113 | mandatory-to-implement algorithms or algorithms so weak that they
114 | cannot be recommended. Any algorithm listed in the [DNSKEY-IANA]
115 | and [DS-IANA] registries that are not mentioned in this document
116 | MAY be implemented. For clarification and consistency, an
117 | algorithm will be specified as MAY in this document only when it
118 | has been downgraded from a MUST or a RECOMMENDED to a MAY.
120 That paragraph is now replaced with the following:
122 | This document provides recommendations with respect to mandatory-
123 | to-implement algorithms, algorithms so weak that they cannot be
124 | recommended, and algorithms defined in RFCs that are not on the
125 | standards track. Any algorithm listed in the [DNSKEY-IANA] and
126 | [DS-IANA] registries that are not mentioned in this document MAY
127 | be implemented. For clarification and consistency, an algorithm
128 | will be specified as MAY in this document only when it has been
129 | downgraded from a MUST or a RECOMMENDED to a MAY.
131 This update is also reflected in the IANA considerations in
1344. IANA Considerations
136 In the "Domain Name System Security (DNSSEC) NextSECure3 (NSEC3)
137 Parameters" registry, the registration procedure for "DNSSEC NSEC3
138 Flags", "DNSSEC NSEC3 Hash Algorithms", and "DNSSEC NSEC3PARAM Flags"
139 has been changed from "Standards Action" to "RFC Required", and this
140 document has been added as a reference.
142 In the "DNSSEC Delegation Signer (DS) Resource Record (RR) Type
143 Digest Algorithms" registry, the registration procedure for "Digest
144 Algorithms" has been changed from "Standards Action" to "RFC
145 Required", and this document has been added as a reference.
1475. Security Considerations
149 Changing the requirements for adding security algorithms to IANA
150 registries as described in this document will make it easier to add
151 both good and bad algorithms to the registries. It is impossible to
152 weigh the security impact of those two changes.
154 Administrators of DNSSEC-signed zones and validating resolvers may
155 have been making security decisions based on the contents of the IANA
156 registries. This was a bad idea in the past, and now it is an even
157 worse idea because there will be more algorithms in those registries
158 that may not have gone through IETF review. Security decisions about
159 which algorithms are safe and not safe should be made by reading the
160 security literature, not by looking in IANA registries.
1646.1. Normative References
166 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
167 Requirement Levels", BCP 14, RFC 2119,
168 DOI 10.17487/RFC2119, March 1997,
169 <https://www.rfc-editor.org/info/rfc2119>.
171 [RFC4033] Arends, R., Austein, R., Larson, M., Massey, D., and S.
172 Rose, "DNS Security Introduction and Requirements",
173 RFC 4033, DOI 10.17487/RFC4033, March 2005,
174 <https://www.rfc-editor.org/info/rfc4033>.
176 [RFC4034] Arends, R., Austein, R., Larson, M., Massey, D., and S.
177 Rose, "Resource Records for the DNS Security Extensions",
178 RFC 4034, DOI 10.17487/RFC4034, March 2005,
179 <https://www.rfc-editor.org/info/rfc4034>.
181 [RFC4035] Arends, R., Austein, R., Larson, M., Massey, D., and S.
182 Rose, "Protocol Modifications for the DNS Security
183 Extensions", RFC 4035, DOI 10.17487/RFC4035, March 2005,
184 <https://www.rfc-editor.org/info/rfc4035>.
186 [RFC5155] Laurie, B., Sisson, G., Arends, R., and D. Blacka, "DNS
187 Security (DNSSEC) Hashed Authenticated Denial of
188 Existence", RFC 5155, DOI 10.17487/RFC5155, March 2008,
189 <https://www.rfc-editor.org/info/rfc5155>.
191 [RFC6014] Hoffman, P., "Cryptographic Algorithm Identifier
192 Allocation for DNSSEC", RFC 6014, DOI 10.17487/RFC6014,
193 November 2010, <https://www.rfc-editor.org/info/rfc6014>.
195 [RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for
196 Writing an IANA Considerations Section in RFCs", BCP 26,
197 RFC 8126, DOI 10.17487/RFC8126, June 2017,
198 <https://www.rfc-editor.org/info/rfc8126>.
200 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
201 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
202 May 2017, <https://www.rfc-editor.org/info/rfc8174>.
204 [RFC8624] Wouters, P. and O. Sury, "Algorithm Implementation
205 Requirements and Usage Guidance for DNSSEC", RFC 8624,
206 DOI 10.17487/RFC8624, June 2019,
207 <https://www.rfc-editor.org/info/rfc8624>.
2096.2. Informative References
211 [RFC3658] Gudmundsson, O., "Delegation Signer (DS) Resource Record
212 (RR)", RFC 3658, DOI 10.17487/RFC3658, December 2003,
213 <https://www.rfc-editor.org/info/rfc3658>.
217 Donald Eastlake, Murray Kucherawy, Dan Harkins, Martin Duke, and
218 Benjamin Kaduk contributed to this document.
225 Email: paul.hoffman@icann.org