NETCONF Working Group P. Andersson Internet-Draft Cisco Systems Updates: 6243 (if approved) 2 April 2024 Intended status: Standards Track Expires: 4 October 2024 YANG Model for the NETCONF default attribute draft-andersson-netconf-defaults-yang-00 Abstract This document defines a YANG module with the "default" attribute using the namespace and prefix defined in [RFC6243]. This enables usage of the "default" attribute in e.g. YANG JSON encoding. 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 4 October 2024. Copyright Notice Copyright (c) 2024 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. Andersson Expires 4 October 2024 [Page 1] Internet-Draft NETCONF default attribute YANG April 2024 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. The "ietf-defaults" Module . . . . . . . . . . . . . . . . . 2 2.1. YANG Module . . . . . . . . . . . . . . . . . . . . . . . 2 3. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 4 3.1. The "IETF XML" Registry . . . . . . . . . . . . . . . . . 4 3.2. The "YANG Module Names" Registry . . . . . . . . . . . . 4 4. Security Considerations . . . . . . . . . . . . . . . . . . . 4 4.1. Regarding the "ietf-defaults" YANG Module . . . . . . . . 4 5. References . . . . . . . . . . . . . . . . . . . . . . . . . 4 5.1. Normative References . . . . . . . . . . . . . . . . . . 4 5.2. Informative References . . . . . . . . . . . . . . . . . 6 Appendix A. YANG JSON Example . . . . . . . . . . . . . . . . . 6 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 8 1. Introduction YANG metadata [RFC7952] defines that attributes should be namespace- qualified, which for YANG JSON [RFC7951] means module-name:attribute. This becomes a problem since the "default" attribute defined in [RFC6243] doesn't define it in a YANG module, but instead defines the "default" attribute in XML Schema. The result is that it is impossible to emit the "default" attribute using YANG JSON encoding, since there is no corresponding YANG module name to use. For NETCONF this is not a problem since the prefix "wd" is defined with the corresponding namespace "urn:ietf:params:xml:ns:netconf:default:1.0". 2. The "ietf-defaults" Module The "ietf-defaults" module defines the "default" attribute. 2.1. YANG Module This YANG module has normative references to [RFC6243], [RFC7951], and [RFC7952]. file "ietf-defaults@2024-04-03.yang" module ietf-defaults { yang-version 1.1; namespace "urn:ietf:params:xml:ns:netconf:default:1.0"; prefix wd; import ietf-yang-metadata { prefix md; reference Andersson Expires 4 October 2024 [Page 2] Internet-Draft NETCONF default attribute YANG April 2024 "RFC 7952: Defining and Using Metadata with YANG"; } organization "IETF NETCONF (Network Configuration) Working Group"; contact "WG Web: https://datatracker.ietf.org/wg/netconf WG List: NETCONF WG list Authors: Per Andersson "; description "This module defines the 'default' attribute in YANG previously only defined in XML Schema in RFC 6243 Section 6. Copyright (c) 2024 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 Revised 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 version of this YANG module is part of RFC XXXX (https://www.rfc-editor.org/info/rfcXXXX); see the RFC itself for full legal notices. 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 (RFC 2119) (RFC 8174) when, and only when, they appear in all capitals, as shown here."; revision 2024-04-03 { description "Initial revision."; reference "RFC XXXX: YANG Model for the NETCONF default attribute"; } md:annotation default { type boolean; description "This annotation is only relevant if the server supports the Andersson Expires 4 October 2024 [Page 3] Internet-Draft NETCONF default attribute YANG April 2024 'report-all-tagged' defaults retrieval mode. For details see RFC 6243."; reference "RFC 6243: With-defaults Capability for NETCONF"; } } 3. IANA Considerations 3.1. The "IETF XML" Registry This document registers one URI in the "ns" subregistry of the IETF XML Registry [RFC3688] maintained at https://www.iana.org/assignments/xml-registry/xml-registry.xhtml#ns. Following the format in [RFC3688], the following registration is requested: URI: urn:ietf:params:xml:ns:netconf:default:1.0 Registrant Contact: The IESG. XML: N/A, the requested URI is an XML namespace. Reference: RFC 6243, RFC XXXX 3.2. The "YANG Module Names" Registry This document registers one YANG module in the YANG Module Names registry [RFC6020] maintained at https://www.iana.org/assignments/ yang-parameters/yang-parameters.xhtml. Following the format defined in [RFC6020], the below registration is requested: name: ietf-defaults namespace: urn:ietf:params:xml:ns:netconf:default:1.0 prefix: wd Reference: RFC XXXX 4. Security Considerations 4.1. Regarding the "ietf-defaults" YANG Module This document defines an extension to existing NETCONF and RESTCONF protocol operations. It does not introdue any new or increased security risks into the management system. 5. References 5.1. Normative References Andersson Expires 4 October 2024 [Page 4] Internet-Draft NETCONF default attribute YANG April 2024 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, DOI 10.17487/RFC3688, January 2004, . [RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed., and A. Bierman, Ed., "Network Configuration Protocol (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011, . [RFC6242] Wasserman, M., "Using the NETCONF Protocol over Secure Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011, . [RFC6243] Bierman, A. and B. Lengyel, "With-defaults Capability for NETCONF", RFC 6243, DOI 10.17487/RFC6243, June 2011, . [RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language", RFC 7950, DOI 10.17487/RFC7950, August 2016, . [RFC7951] Lhotka, L., "JSON Encoding of Data Modeled with YANG", RFC 7951, DOI 10.17487/RFC7951, August 2016, . [RFC7952] Lhotka, L., "Defining and Using Metadata with YANG", RFC 7952, DOI 10.17487/RFC7952, August 2016, . [RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017, . [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, . [RFC8341] Bierman, A. and M. Bjorklund, "Network Configuration Access Control Model", STD 91, RFC 8341, DOI 10.17487/RFC8341, March 2018, . Andersson Expires 4 October 2024 [Page 5] Internet-Draft NETCONF default attribute YANG April 2024 [RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018, . 5.2. Informative References [RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF)", RFC 6020, DOI 10.17487/RFC6020, October 2010, . Appendix A. YANG JSON Example The following example shows the example from Section A.3.2. = 'report-all-tagged' in [RFC6243] encoded as YANG JSON encoded data. The request is adapted for RESTCONF [RFC8040]. Andersson Expires 4 October 2024 [Page 6] Internet-Draft NETCONF default attribute YANG April 2024 GET /restconf/data/example:interfaces?with-defaults=report-all-tagged Accept: application/yang-data+json HTTP/1.1 200 OK Date: Wed, 03 Apr 2024 01:18:51 GMT Server: example-server Content-Type: application/yang-data+json { "example:interfaces": [ { "name": "eth0", "mtu": 8192, "status": "up", "@status": { "ietf-defaults:default": true" } }, { "name": "eth1", "mtu": 1500, "@mtu": { "ietf-defaults:default": true" } "status": "up", "@status": { "ietf-defaults:default": true" } }, { "name": "eth2", "mtu": 9000, "status": "not feeling so good" }, { "name": "eth3", "mtu": 1500, "@mtu": { "ietf-defaults:default": true" } "status": "waking up" } ] } YANG JSON encoded data with "default" attribute. Andersson Expires 4 October 2024 [Page 7] Internet-Draft NETCONF default attribute YANG April 2024 Author's Address Per Andersson Cisco Systems Email: per.ietf@ionio.se Andersson Expires 4 October 2024 [Page 8]