YANG Types for DNS Classes and Resource Record Types
draft-ietf-dnsop-iana-class-type-yang-03
The information below is for an old version of the document.
| Document | Type |
This is an older version of an Internet-Draft that was ultimately published as RFC 9108.
|
|
|---|---|---|---|
| Authors | Ladislav Lhotka , Petr Špaček | ||
| Last updated | 2021-06-03 (Latest revision 2021-05-24) | ||
| Replaces | draft-lhotka-dnsop-iana-class-type-yang | ||
| RFC stream | Internet Engineering Task Force (IETF) | ||
| Formats | |||
| Reviews |
GENART Last Call review
(of
-02)
by Joel Halpern
Ready w/issues
|
||
| Additional resources | Mailing list discussion | ||
| Stream | WG state | Submitted to IESG for Publication | |
| Document shepherd | Benno Overeinder | ||
| Shepherd write-up | Show Last changed 2021-05-07 | ||
| IESG | IESG state | Became RFC 9108 (Proposed Standard) | |
| Consensus boilerplate | Yes | ||
| Telechat date |
(None)
Needs 2 more YES or NO OBJECTION positions to pass. |
||
| Responsible AD | Warren "Ace" Kumari | ||
| Send notices to | benno@NLnetLabs.nl | ||
| IANA | IANA review state | IANA OK - Actions Needed | |
| IANA expert review state | Expert Reviews OK |
draft-ietf-dnsop-iana-class-type-yang-03
Lhotka & Spacek Expires 25 November 2021 [Page 2] Internet-Draft iana-dns-class-rr-type-yang May 2021 translated into corresponding YANG types or other structures. Such translations should be straightforward and relatively uncontroversial. This document provides a translation of two fundamental DNS-related IANA registries to YANG. It contains the initial revision of the YANG module "iana-dns-class-rr-type" that defines derived types for the common parameters of DNS resource records (RR): class and type. These YANG types, "dns-class" and "rr-type", reflect the IANA registries "DNS CLASSes" and "Resource Record (RR) TYPEs" [IANA-DNS-PARAMETERS]. Appendix A contains an XSLT 1.0 stylesheet that is intended to be used by IANA for generating the initial revision of the "iana-dns- class-rr-type" YANG module. Subsequently, whenever a new class or RR type is added to the above registries, IANA will also update the "iana-dns-class-rr-type" YANG module, following the instructions in Section 4 below. 2. Terminology 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 only when, they appear in all capitals, as shown here. The terminology for describing YANG data models is found in [RFC7950]. 3. YANG Design Considerations The IANA document "Domain Name System (DNS) Parameters" [IANA-DNS-PARAMETERS] contains altogether thirteen registries. The YANG module "iana-dns-class-rr-type" defines derived types corresponding to only two of the registries that are essential for data models involving zone data, namely "DNS CLASSes" and "Resource Record (RR) TYPEs". It is expected that the remaining registries in [IANA-DNS-PARAMETERS], as well as other DNS-related IANA registries, will be analogically reflected in future YANG modules as necessary. This way, an appropriate combination of YANG modules can be chosen depending on which YANG types are needed for a given data modeling purpose. The registries "DNS CLASSes" and "Resource Record (RR) TYPEs" are transformed into YANG enumeration types "dns-class-name" and "rr- type-name", respectively. This is the initial fragment of the former: Lhotka & Spacek Expires 25 November 2021 [Page 3] Internet-Draft iana-dns-class-rr-type-yang May 2021 typedef dns-class-name { type enumeration { enum IN { value 1; description "Internet (IN)"; reference "RFC 1035"; } ... } ... } The other derived type, "rr-type-name", is defined analogically. [RFC3597] introduced the option of specifying a class or RR type via its assigned decimal number, as an alternative to the mnemonic name. For example, the "IN" class can be equivalently written as "CLASS1", and "AAAA" type can be written as "TYPE28". Accordingly, the derived types "dns-class" and "rr-type" are defined in the YANG module as a union of two member types: * 16-bit decimal integer ("uint16") * mnemonic name belonging to the enumerations "dns-class-name" and "rr-type-name", respectively. For instance, the "rr-type" type is defined as follows: typedef rr-type { type union { type uint16; type rr-type-name; } description "This type allows for referring to a DNS resource record type using either the assigned mnemonic name or numeric value."; } As unassigned and reserved class and RR type values are not included in the mnemonic name enumerations, they can only be specified using their decimal values. Lhotka & Spacek Expires 25 November 2021 [Page 4] Internet-Draft iana-dns-class-rr-type-yang May 2021 4. IANA Considerations RFC Editor: In this section, replace all occurrences of "XXXX" with the actual RFC number (and remove this note). This section deals with actions and processes necessary for IANA to undertake to maintain the "iana-dns-class-rr-type" YANG module. This YANG module is intended to reflect the "DNS CLASSes" and "Resource Record (RR) TYPEs" registries in [IANA-DNS-PARAMETERS]. The most recent revision of the YANG module is available from the "YANG Parameters" registry [IANA-YANG-PARAMETERS]. Upon publication of this document, the initial revision of the "iana- dns-class-rr-type" YANG module SHALL be created by applying the XSLT stylesheet from Appendix A to the XML version of [IANA-DNS-PARAMETERS]. IANA SHALL add this note to the "iana-dns-class-rr-type" item of the "YANG Module Names" registry [IANA-YANG-PARAMETERS]: | Classes and types of DNS resource records must not be directly | added to the "iana-dns-class-rr-type" YANG module. They must | instead be added to the "DNS CLASSes" and "Resource Record (RR) | TYPEs" registries, respectively. When a new DNS class or RR type is added to the "DNS CLASSes" or "Resource Record (RR) TYPEs" registry, a new "enum" statement SHALL be added to the "dns-class-name" or "rr-type-name" type, respectively. The assigned name defined by the "enum" statement SHALL be the same as the mnemonic name of the new class or type. The following substatements to the "enum" statement SHALL be defined: "value": Use the decimal value from the registry. "status": Include only if a class or type registration has been deprecated or obsoleted. In both cases, use the value "obsolete" as the argument of the "status" statement. "description": Replicate the corresponding information from the registry, namely the full name of the new DNS class, or the meaning of the new RR type, if any. "reference": Replicate the reference(s) from the registry. Unassigned or reserved values SHALL NOT be included in the "dns- class-name" and "rr-type-name" enumeration types. Lhotka & Spacek Expires 25 November 2021 [Page 5] Internet-Draft iana-dns-class-rr-type-yang May 2021 Each time the "iana-dns-class-rr-type" YANG module is updated, a new "revision" statement SHALL be added before the existing "revision" statements. IANA SHALL add this new note to the "DNS CLASSes" and "Resource Record (RR) TYPEs" registries: | When this registry is modified, the YANG module "iana-dns-class- | rr-type" must be updated as defined in RFC XXXX. The "Reference" text in the "DNS CLASSes" registry SHALL be updated as follows: | OLD: | [RFC6895] | | NEW: | [RFC6895][RFCXXXX] The "Reference" text in the "Resource Record (RR) TYPEs" registry SHALL be updated as follows: | OLD: | [RFC6895][RFC1035] | | NEW: | [RFC6895][RFC1035][RFCXXXX] 4.1. URI Registrations This document registers a URI in the "IETF XML Registry" [RFC3688]. The following registration has been made: | URI: urn:ietf:params:xml:ns:yang:iana-dns-class-rr-type | Registrant Contact: The IESG. | XML: N/A, the requested URI is an XML namespace. 4.2. YANG Module Registrations This document registers a YANG module in the "YANG Module Names" registry [RFC6020]. The following registration has been made: | name: iana-dns-class-rr-type | namespace: urn:ietf:params:xml:ns:yang:iana-dns-class-rr-type | prefix: dnsct | reference: RFC XXXX Lhotka & Spacek Expires 25 November 2021 [Page 6] Internet-Draft iana-dns-class-rr-type-yang May 2021 5. Security Considerations This documents translates two IANA registries into YANG data types and otherwise introduces no technology or protocol. Consequently, there are no security issues to be considered for this document. 6. Normative References [IANA-DNS-PARAMETERS] Internet Assigned Numbers Authority, "Domain Name System (DNS) Parameters", <https://www.iana.org/assignments/dns-parameters>. [IANA-YANG-PARAMETERS] Internet Assigned Numbers Authority, "YANG Parameters", <https://www.iana.org/assignments/yang-parameters>. [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>. [RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, DOI 10.17487/RFC3688, January 2004, <https://www.rfc-editor.org/info/rfc3688>. [RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF)", RFC 6020, DOI 10.17487/RFC6020, October 2010, <https://www.rfc-editor.org/info/rfc6020>. [RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language", RFC 7950, DOI 10.17487/RFC7950, August 2016, <https://www.rfc-editor.org/info/rfc7950>. [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>. [W3C.REC-xslt-19991116] Clark, J., "XSL Transformations (XSLT) Version 1.0", World Wide Web Consortium Recommendation REC-xslt-19991116, 16 November 1999, <https://www.w3.org/TR/1999/REC-xslt-19991116>. 7. Informative References Lhotka & Spacek Expires 25 November 2021 [Page 7] Internet-Draft iana-dns-class-rr-type-yang May 2021 [RFC3597] Gustafsson, A., "Handling of Unknown DNS Resource Record (RR) Types", RFC 3597, DOI 10.17487/RFC3597, September 2003, <https://www.rfc-editor.org/info/rfc3597>. Appendix A. XSLT Stylesheet RFC Editor: In this section, replace all occurrences of "XXXX" with the actual RFC number (and remove this note). This appendix contains an XSLT 1.0 stylesheet [W3C.REC-xslt-19991116] that is intended to be used for generating the initial revision of the "iana-dns-class-rr-type" YANG module. This is achieved by applying the stylesheet to the XML version of the IANA registry "Domain Name System (DNS) Parameters" [IANA-DNS-PARAMETERS] that was current at the time when this document was published. Using the ubiquitous xsltproc tool, the YANG module text can be generated with this command: $ xsltproc iana-dns-class-rr-type.xsl dns-parameters.xml <CODE BEGINS> file "iana-dns-class-rr-type.xsl" <?xml version="1.0" standalone="yes"?> <stylesheet xmlns="http://www.w3.org/1999/XSL/Transform" xmlns:iana="http://www.iana.org/assignments" version="1.0"> <output method="text"/> <strip-space elements="*"/> <variable name="dq">"</variable> <variable name="sq">'</variable> <variable name="lf">
</variable> <variable name="module-intro"> <text>module iana-dns-class-rr-type { yang-version 1.1; namespace "urn:ietf:params:xml:ns:yang:iana-dns-class-rr-type"; prefix dnsct; organization "Internet Assigned Numbers Authority (IANA)"; contact " Internet Assigned Numbers Authority Postal: ICANN 4676 Admiralty Way, Suite 330 Marina del Rey, CA 90292 Lhotka & Spacek Expires 25 November 2021 [Page 8] Internet-Draft iana-dns-class-rr-type-yang May 2021 Tel: +1 310 823 9358 <mailto:iana@iana.org>"; description "This YANG module translates IANA registries 'DNS CLASSes' and 'Resource Record (RR) TYPEs' to YANG derived types. Copyright (c) 2020 IETF Trust and the persons identified as authors of the code. All rights reserved. Redistribution and use in source and binary forms, with or without modification, is permitted pursuant to, and subject to the license terms contained in, the Simplified BSD License set forth in Section 4.c of the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info). This initial version of this YANG module was generated from the corresponding IANA registries using a XSLT stylesheet from Appendix A of RFC XXXX (https://tools.ietf.org/html/rfcXXXX); see the RFC itself for full legal notices."; reference "IANA 'Domain Name System (DNS) Parameters' registry https://www.iana.org/assignments/dns-parameters";</text> <text>

</text> </variable> <template name="enum"> <param name="id"/> <value-of select="concat(' enum ', $id)"/> <text> {
 value </text> <value-of select="concat(iana:value, ';
')"/> <if test="contains(iana:description, 'OBSOLETE')"> <text> status obsolete;
</text> </if> <apply-templates select="iana:description"/> <variable name="xrefs" select="iana:xref[@type!='note']"/> <if test="$xrefs"> <text> reference
 "</text> <if test="count($xrefs)>1">- </if> <apply-templates select="iana:xref[@type!='note']"/> </if> <text> }
</text> </template> Lhotka & Spacek Expires 25 November 2021 [Page 9] Internet-Draft iana-dns-class-rr-type-yang May 2021 <template match="/"> <value-of select="$module-intro"/> <apply-templates select="iana:registry[@id='dns-parameters']"/> <text>}
</text> </template> <template match="iana:registry[@id='dns-parameters']"> <apply-templates select="iana:updated"/> <apply-templates select="iana:registry[@id='dns-parameters-2']"/> <apply-templates select="iana:registry[@id='dns-parameters-4']"/> </template> <template match="iana:updated"> <value-of select="concat(' revision ', ., ' {')"/> <text> description "Initial revision."; reference "RFC XXXX: YANG Types for DNS Classes and Resource Record Types"; } /* Typedefs */

</text> </template> <template match="iana:registry[@id='dns-parameters-2']"> <text> typedef dns-class-name {
</text> <text> type enumeration {
</text> <apply-templates select="iana:record[not(iana:description='Unassigned' or starts-with(iana:description,'Reserved'))]" mode="class"/> <text> } description "This enumeration type defines mnemonic names and corresponding numeric values of DNS classes."; reference "RFC 6895: Domain Name System (DNS) IANA Considerations"; } typedef dns-class { type union { type uint16; type dns-class-name; } description Lhotka & Spacek Expires 25 November 2021 [Page 10] Internet-Draft iana-dns-class-rr-type-yang May 2021 "This type allows for referring to a DNS class using either the assigned mnemonic name or numeric value."; }

</text> </template> <template match="iana:registry[@id='dns-parameters-4']"> <text> typedef rr-type-name {
</text> <text> type enumeration {
</text> <apply-templates select="iana:record[iana:type!='Unassigned' and iana:type!='Private use' and iana:type!='Reserved']" mode="rr-type"/> <text> } description "This enumeration type defines mnemonic names and corresponding numeric values of DNS resource record types."; reference "- RFC 6895: Domain Name System (DNS) IANA Considerations - RFC 1035: Domain Names - Implementation and Specification"; } typedef rr-type { type union { type uint16; type rr-type-name; } description "This type allows for referring to a DNS resource record type using either the assigned mnemonic name or numeric value."; }
</text> </template> <template match="iana:record" mode="class"> <call-template name="enum"> <with-param name="id"> <choose> <when test="contains(iana:description,'(')"> <value-of select="substring-before(substring-after( iana:description, '('), ')')"/> </when> <otherwise> <value-of select="substring-after(iana:description, ' ')"/> </otherwise> </choose> </with-param> </call-template> Lhotka & Spacek Expires 25 November 2021 [Page 11] Internet-Draft iana-dns-class-rr-type-yang May 2021 </template> <template match="iana:record" mode="rr-type"> <call-template name="enum"> <with-param name="id" select="iana:type"/> </call-template> </template> <template match="iana:description"> <text> description
 </text> <value-of select="concat($dq, ., $dq, ';
')"/> </template> <template match="iana:xref"> <choose> <when test="@type='rfc'"> <value-of select="concat('RFC ', substring-after(@data, 'rfc'))"/> </when> <when test="@type='person'"> <apply-templates select="/iana:registry/iana:people/iana:person[ @id=current()/@data]"/> </when> <when test="@type='text'"> <value-of select="translate(., $dq, $sq)"/> </when> <otherwise> <value-of select="@data"/> </otherwise> </choose> <choose> <when test="position()=last()"> <text>";
</text> </when> <otherwise> <text>
 - </text> </otherwise> </choose> </template> <template match="iana:person"> <value-of select="concat(iana:name, ' <', iana:uri, '>')"/> </template> </stylesheet> <CODE ENDS> Lhotka & Spacek Expires 25 November 2021 [Page 12] Internet-Draft iana-dns-class-rr-type-yang May 2021 Authors' Addresses Ladislav Lhotka CZ.NIC Czech Republic Email: ladislav.lhotka@nic.cz Petr Spacek Internet Systems Consortium Czech Republic Email: pspacek@isc.org Lhotka & Spacek Expires 25 November 2021 [Page 13]