Internet A. Lindem Internet-Draft S. Litkowski Intended status: Standards Track Cisco Systems Expires: July 9, 2021 Y. Qu Futurewei January 5, 2021 IS-IS YANG Model Augmentations for Additional Features - Version 1 draft-acee-lsr-isis-yang-augmentation-v1-04 Abstract This document defines YANG data modules augmenting the IETF IS-IS YANG model to provide support for IS-IS Minimum Remaining Lifetime as defined in RFC 7987, and IS-IS Application-Specific Link Attributes as defined in RFC 8919. 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 July 9, 2021. Copyright Notice Copyright (c) 2021 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 Simplified BSD License text as described in Section 4.e of Lindem, et al. Expires July 9, 2021 [Page 1] Internet-Draft ISIS YANG Augments V1 January 2021 the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1.1. Requirements Language . . . . . . . . . . . . . . . . . . 2 1.2. Tree diagram . . . . . . . . . . . . . . . . . . . . . . 3 2. YANG Module for IS-IS Minimum Remaining Lifetime . . . . . . 3 3. YANG Module for IS-IS Application-Specific Link Attributes . 4 4. Security Considerations . . . . . . . . . . . . . . . . . . . 14 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15 6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 15 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 15 7.1. Normative References . . . . . . . . . . . . . . . . . . 15 7.2. Informative References . . . . . . . . . . . . . . . . . 17 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 17 1. Overview YANG [RFC6020] [RFC7950] is a data definition language used to define the contents of a conceptual data store that allows networked devices to be managed using NETCONF [RFC6241]. YANG is proving relevant beyond its initial confines, as bindings to other interfaces (e.g., ReST) and encodings other than XML (e.g., JSON) are being defined. Furthermore, YANG data models can be used as the basis for implementation of other interfaces, such as CLI and programmatic APIs. This document defines YANG data modules augmenting the IETF IS-IS YANG model [I-D.ietf-isis-yang-isis-cfg], which itself augments [RFC8349], to provide support for configuration and operational state for the following IS-IS features: RFC7987: IS-IS Minimum Remaining Lifetime[RFC7987]. RFC8919: IS-IS Application-Specific Link Attributes[RFC8919]. The augmentations defined in this document requires support for the IS-IS base model[I-D.ietf-isis-yang-isis-cfg] which defines basic IS- IS configuration and state. The IS-IS YANG model augments the ietf- routing YANG model defined in [RFC8349]. 1.1. 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 Lindem, et al. Expires July 9, 2021 [Page 2] Internet-Draft ISIS YANG Augments V1 January 2021 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here. 1.2. Tree diagram Tree diagrams used in this document follow the notation defined in [RFC8340]. 2. YANG Module for IS-IS Minimum Remaining Lifetime This document defines a YANG module for IS-IS Minimum Remaining Lifetime as defined in [RFC7987]. It is an augmentation of the IS-IS base model. module: ietf-isis-remaining-lifetime notifications: +---n corrupt-remaining-lifetime +--ro routing-protocol-name? -> /rt:routing /control-plane-protocols /control-plane-protocol/name +--ro isis-level? level +--ro lsp-id? isis:lsp-id file "ietf-isis-remaining-lifetime@2021-01-05.yang" module ietf-isis-remaining-lifetime { yang-version 1.1; namespace "urn:ietf:params:xml:ns:yang:ietf-isis-remaining-lifetime"; prefix isis-remaining-lifetime; import ietf-isis { prefix "isis"; } organization "IETF LSR - Link State Routing Working Group"; contact "WG Web: WG List: Author: Yingzhen Qu Author: Acee Lindem Author: Stephane Litkowski Lindem, et al. Expires July 9, 2021 [Page 3] Internet-Draft ISIS YANG Augments V1 January 2021 "; description "This YANG module defines the configuration and operational state for IS-IS Minimum Remaining Lifetime feature as defined in RFC 7987. Copyright (c) 2021 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 (http://trustee.ietf.org/license-info). This version of this YANG module is part of RFC XXXX; see the RFC itself for full legal notices."; reference "RFC XXXX"; revision 2021-01-05 { description "Initial version"; reference "RFC XXXX: A YANG Data Model for IS-IS."; } notification corrupt-remaining-lifetime { uses isis:notification-instance-hdr; leaf lsp-id { type isis:lsp-id; description "LSP ID"; } description "This notification is sent when the system detects correpted lifetime of an LSP."; reference "RFC 7987: IS-IS Minimum Remaining Lifetime"; } } 3. YANG Module for IS-IS Application-Specific Link Attributes This document defines a YANG module for IS-IS Application-Specific Link Attributes [RFC8919]. It is an augmentation of the IS-IS base model. Lindem, et al. Expires July 9, 2021 [Page 4] Internet-Draft ISIS YANG Augments V1 January 2021 module: ietf-isis-link-attr augment /rt:routing/rt:control-plane-protocols /rt:control-plane-protocol/isis:isis/isis:interfaces /isis:interface: +--rw isis-link-attr +--rw (link-attr-op-mode) +--:(legacy) | +--rw legacy? empty +--:(transition) | +--rw transition? empty +--:(app-specific) +--rw app-specific? empty augment /rt:routing/rt:control-plane-protocols /rt:control-plane-protocol/isis:isis/isis:database /isis:levels/isis:lsp/isis:extended-is-neighbor /isis:neighbor/isis:instances/isis:instance: +--ro application-specific-link-attributes-sub-tlvs +--ro asla-sub-tlvs* [] +--ro l-flag? boolean +--ro sabm-length? uint8 +--ro r-flag? boolean +--ro udabm-length? uint8 +--ro sabm | +--ro sabm-bits* identityref +--ro udabm +--ro unknown-tlvs +--ro unknown-tlv* [] +--ro type? uint16 +--ro length? uint16 +--ro value? yang:hex-string augment /rt:routing/rt:control-plane-protocols /rt:control-plane-protocol/isis:isis/isis:database /isis:levels/isis:lsp/isis:mt-is-neighbor/isis:neighbor /isis:instances/isis:instance: +--ro application-specific-link-attributes-sub-tlvs +--ro asla-sub-tlvs* [] +--ro l-flag? boolean +--ro sabm-length? uint8 +--ro r-flag? boolean +--ro udabm-length? uint8 +--ro sabm | +--ro sabm-bits* identityref +--ro udabm +--ro unknown-tlvs +--ro unknown-tlv* [] +--ro type? uint16 +--ro length? uint16 +--ro value? yang:hex-string Lindem, et al. Expires July 9, 2021 [Page 5] Internet-Draft ISIS YANG Augments V1 January 2021 augment /rt:routing/rt:control-plane-protocols /rt:control-plane-protocol/isis:isis/isis:database /isis:levels/isis:lsp: +--ro application-specific-srlg-tlv +--ro as-srlg-tlvs* [] +--ro neighbor-system-id? isis:system-id +--ro pseudo-node-id? uint8 +--ro l-flag? boolean +--ro sabm-length? uint8 +--ro r-flag? boolean +--ro udabm-length? uint8 +--ro sabm | +--ro sabm-bits* identityref +--ro udabm +--ro length-of-sub-tlvs? uint8 +--ro link-id-sub-tlvs | +--ro link-local-remote-ids | | +--ro link-local-id? union | | +--ro link-remote-id? union | +--ro ipv4-interface-addr | | +--ro ipv4-int-addr? inet:ipv4-address | +--ro ipv4-neighbor-addr | | +--ro ipv4-neighbor-addr? inet:ipv4-address | +--ro ipv6-interface-addr | | +--ro ipv6-int-addr? inet:ipv6-address | +--ro ipv6-neighbor-addr | +--ro ipv6-neighbor-addr? inet:ipv6-address +--ro srlgs +--ro srlg* uint32 file "ietf-isis-link-attr@2021-01-05.yang" module ietf-isis-link-attr { yang-version 1.1; namespace "urn:ietf:params:xml:ns:yang:ietf-isis-link-attr"; prefix isis-link-attr; import ietf-inet-types { prefix inet; reference "RFC 6991 - Common YANG Data Types"; } import ietf-routing { prefix "rt"; } import ietf-isis { prefix "isis"; Lindem, et al. Expires July 9, 2021 [Page 6] Internet-Draft ISIS YANG Augments V1 January 2021 } organization "IETF LSR - Link State Routing Working Group"; contact "WG Web: WG List: Author: Yingzhen Qu Author: Acee Lindem Author: Stephane Litkowski "; description "This YANG module defines the configuration and operational state for IS-IS application specific link attributes feature as defined in RFC 8919. This YANG model conforms to the Network Management Datastore Architecture (NMDA) as described in RFC 8242. Copyright (c) 2021 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 (http://trustee.ietf.org/license-info). This version of this YANG module is part of RFC XXXX; 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."; reference "RFC XXXX"; revision 2021-01-05 { description "Initial version"; Lindem, et al. Expires July 9, 2021 [Page 7] Internet-Draft ISIS YANG Augments V1 January 2021 reference "RFC XXXX: A YANG Data Model for IS-IS."; } identity sabm-bit { description "Base identity for sabm bits."; reference "RFC 8919: IS-IS Application-Specific Link Attributes"; } identity rsvp-te-bit { base sabm-bit; description "R bit, RSVP-TE."; } identity sr-policy-bit { base sabm-bit; description "S bit, Segment Routing Policy."; } identity lfa-bit { base sabm-bit; description "F bit, Loop Free Alternate (LFA). Includes all LFA types."; } grouping application-identifier-bit-mask { description "Identification of the set of applications associated with link attribute advertisements"; leaf l-flag { type boolean; description "Legacy Flag. When set, all of the applications specified in the bit mask MUST use the legacy advertisements."; } leaf sabm-length { type uint8; description "Standard Application Identifier Bit Mask Length in octets."; } leaf r-flag { type boolean; Lindem, et al. Expires July 9, 2021 [Page 8] Internet-Draft ISIS YANG Augments V1 January 2021 default false; description "Reserved."; } leaf udabm-length { type uint8; description "User Defined Application Identifier Bit Mask Length in octets."; } container sabm { leaf-list sabm-bits { type identityref { base sabm-bit; } description "SABM bits list. This list will contain identities for the bits which are set in the SABA bits."; } description "Standard Application Identifier Bit Mask."; } container udabm { description "User Defined Application Identifier Bit Mask. This container is to be augmented by user defined applications."; } } grouping application-specific-link-attributes-sub-tlv { description "Grouping for specification of the applications and application-specific attribute values."; container application-specific-link-attributes-sub-tlvs { list asla-sub-tlvs { uses application-identifier-bit-mask; uses isis:unknown-tlvs; description "List of application specific link attributes sub-tlvs."; } description "Application specific link attributes sub-tlv."; } } Lindem, et al. Expires July 9, 2021 [Page 9] Internet-Draft ISIS YANG Augments V1 January 2021 grouping application-specific-srlg-tlv { description "Grouping of a TLV to advertise application-specific SRLGs for a given link."; container application-specific-srlg-tlv { list as-srlg-tlvs { leaf neighbor-system-id { type isis:system-id; description "Neighbor System-ID."; } leaf pseudo-node-id { type uint8; description "Pseudo-node ID."; } uses application-identifier-bit-mask; leaf length-of-sub-tlvs { type uint8; description "Length of sub-tlvs."; } container link-id-sub-tlvs { description "Link Identifier sub-TLVs."; container link-local-remote-ids { description "Link local/remote identifier sub-tlv."; leaf link-local-id { type union { type inet:ipv4-address; type uint32; } description "Local identifier of the link. It could be an IPv4 address or a local identifier."; } leaf link-remote-id { type union { type inet:ipv4-address; type uint32; } description "Remote identifier of the link. It could be an IPv4 address or a remotely learned identifier."; } Lindem, et al. Expires July 9, 2021 [Page 10] Internet-Draft ISIS YANG Augments V1 January 2021 } container ipv4-interface-addr { leaf ipv4-int-addr { type inet:ipv4-address; description "IPv4 address for the interface."; } description "IPv4 interface address sub-tlv."; } container ipv4-neighbor-addr { leaf ipv4-neighbor-addr { type inet:ipv4-address; description "IPv4 address for a neighboring router on this link."; } description "IPv4 neighbor address sub-tlv."; } container ipv6-interface-addr { leaf ipv6-int-addr { type inet:ipv6-address; description "IPv6 address for the interface."; } description "IPv6 interface address sub-tlv."; } container ipv6-neighbor-addr { leaf ipv6-neighbor-addr { type inet:ipv6-address; description "IPv6 address for a neighboring router on this link."; } description "IPv6 neighbor address sub-tlv."; } } container srlgs { description "List of SRLGs."; leaf-list srlg { type uint32; description "SRLG value of the link."; } Lindem, et al. Expires July 9, 2021 [Page 11] Internet-Draft ISIS YANG Augments V1 January 2021 } description "List of application specific SRLG tlvs."; } description "Application specific SRLG tlv."; } } augment "/rt:routing/" + "rt:control-plane-protocols/rt:control-plane-protocol"+ "/isis:isis/isis:interfaces/isis:interface" { when "/rt:routing/rt:control-plane-protocols/"+ "rt:control-plane-protocol/rt:type = 'isis:isis'" { description "This augment ISIS routing protocol when used."; } description "This augments ISIS protocol configuration with TE attributes per application."; container isis-link-attr { choice link-attr-op-mode { mandatory "true"; leaf legacy { type empty; description "Only send legacy advertisements."; } leaf transition { type empty; description "Send both application-specific and legacy advertisements."; } leaf app-specific{ type empty; description "Only send application-specific advertisements."; } description "Link attributes mode"; } description "Link attributes operation mode."; } } Lindem, et al. Expires July 9, 2021 [Page 12] Internet-Draft ISIS YANG Augments V1 January 2021 /* TLV 22 */ augment "/rt:routing/" + "rt:control-plane-protocols/rt:control-plane-protocol"+ "/isis:isis/isis:database/isis:levels/isis:lsp"+ "/isis:extended-is-neighbor/isis:neighbor"+ "/isis:instances/isis:instance" { when "/rt:routing/rt:control-plane-protocols/"+ "rt:control-plane-protocol/rt:type = 'isis:isis'" { description "This augment ISIS routing protocol when used"; } description "This augments ISIS protocol LSDB TLV22."; uses application-specific-link-attributes-sub-tlv; } /* TLV 223 */ augment "/rt:routing/" + "rt:control-plane-protocols/rt:control-plane-protocol"+ "/isis:isis/isis:database/isis:levels/isis:lsp"+ "/isis:mt-is-neighbor/isis:neighbor"+ "/isis:instances/isis:instance" { when "/rt:routing/rt:control-plane-protocols/"+ "rt:control-plane-protocol/rt:type = 'isis:isis'" { description "This augment ISIS routing protocol when used"; } description "This augments ISIS protocol LSDB TLV22."; uses application-specific-link-attributes-sub-tlv; } /* application-specific SRLG TLV 238 */ augment "/rt:routing/" + "rt:control-plane-protocols/rt:control-plane-protocol"+ "/isis:isis/isis:database/isis:levels/isis:lsp" { when "/rt:routing/rt:control-plane-protocols/"+ "rt:control-plane-protocol/rt:type = 'isis:isis'" { description "This augment ISIS routing protocol when used"; } description "This augments ISIS protocol LSDB router capability."; uses application-specific-srlg-tlv; } Lindem, et al. Expires July 9, 2021 [Page 13] Internet-Draft ISIS YANG Augments V1 January 2021 } 4. Security Considerations The YANG modules specified in this document define a schema for data that is designed to be accessed via network management protocols such as NETCONF [RFC6241] or RESTCONF [RFC8040]. The lowest NETCONF layer is the secure transport layer, and the mandatory-to-implement secure transport is Secure Shell (SSH) [RFC6242]. The lowest RESTCONF layer is HTTPS, and the mandatory-to-implement secure transport is TLS [RFC5246]. The NETCONF access control model [RFC6536] provides the means to restrict access for particular NETCONF or RESTCONF users to a pre- configured subset of all available NETCONF or RESTCONF protocol operations and content. There are a number of data nodes defined in the modules that are writable/creatable/deletable (i.e., config true, which is the default). These data nodes may be considered sensitive or vulnerable in some network environments. Write operations (e.g., edit-config) to these data nodes without proper protection can have a negative effect on network operations. These correspond to the following schema nodes: /isis:isis/isis:interfaces/isis:interface/isis-link-attr - Modification of link attributes operation mode could result in traffic being redirected or DoS attack. Some of the readable data nodes in the modules may be considered sensitive or vulnerable in some network environments. It is thus important to control read access (e.g., via get, get-config, or notification) to these data nodes. The exposure of the Link State Database (LSDB) will expose the detailed topology of the network. This may be undesirable since both due to the fact that exposure may facilitate other attacks. Additionally, network operators may consider their topologies to be sensitive confidential data.These correspond to the following schema nodes: /isis:isis/isis:database/isis:levels/isis:lsp/isis:mt-is- neighbor/isis:neighbor/isis:instances/isis:instance/application- specific-link-attributes-sub-tlvs /isis:isis/isis:database/isis:levels/isis:lsp/application- specific-srlg-tlv Lindem, et al. Expires July 9, 2021 [Page 14] Internet-Draft ISIS YANG Augments V1 January 2021 5. IANA Considerations This document registers URIs in the IETF XML registry [RFC3688]. Following the format in [RFC3688], the following registrations is requested to be made: URI: urn:ietf:params:xml:ns:yang:ietf-isis-remaining-lifetime Registrant Contact: The IESG. XML: N/A, the requested URI is an XML namespace. URI: urn:ietf:params:xml:ns:yang:ietf-isis-link-attr Registrant Contact: The IESG. XML: N/A, the requested URI is an XML namespace. This document registers the YANG modules in the YANG Module Names registry [RFC6020]. name: ietf-isis-remaining-lifetime namespace: urn:ietf:params:xml:ns:yang:ietf-isis-remaining-lifetime prefix: isis-remaining-lifetime reference: RFC XXXX name: ietf-isis-link-attr namespace: urn:ietf:params:xml:ns:yang:ietf-isis-link-attr prefix: isis-link-attr reference: RFC XXXX 6. Acknowledgements This document was produced using Marshall Rose's xml2rfc tool. The YANG model was developed using the suite of YANG tools written and maintained by numerous authors. 7. References 7.1. Normative References [I-D.ietf-isis-yang-isis-cfg] Litkowski, S., Yeung, D., Lindem, A., Zhang, Z., and L. Lhotka, "YANG Data Model for IS-IS Protocol", draft-ietf- isis-yang-isis-cfg-42 (work in progress), October 2019. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . Lindem, et al. Expires July 9, 2021 [Page 15] Internet-Draft ISIS YANG Augments V1 January 2021 [RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, DOI 10.17487/RFC3688, January 2004, . [RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security (TLS) Protocol Version 1.2", RFC 5246, DOI 10.17487/RFC5246, August 2008, . [RFC5329] Ishiguro, K., Manral, V., Davey, A., and A. Lindem, Ed., "Traffic Engineering Extensions to OSPF Version 3", RFC 5329, DOI 10.17487/RFC5329, September 2008, . [RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF)", RFC 6020, DOI 10.17487/RFC6020, October 2010, . [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, . [RFC6536] Bierman, A. and M. Bjorklund, "Network Configuration Protocol (NETCONF) Access Control Model", RFC 6536, DOI 10.17487/RFC6536, March 2012, . [RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language", RFC 7950, DOI 10.17487/RFC7950, August 2016, . [RFC7987] Ginsberg, L., Wells, P., Decraene, B., Przygienda, T., and H. Gredler, "IS-IS Minimum Remaining Lifetime", RFC 7987, DOI 10.17487/RFC7987, October 2016, . [RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017, . Lindem, et al. Expires July 9, 2021 [Page 16] Internet-Draft ISIS YANG Augments V1 January 2021 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, . [RFC8349] Lhotka, L., Lindem, A., and Y. Qu, "A YANG Data Model for Routing Management (NMDA Version)", RFC 8349, DOI 10.17487/RFC8349, March 2018, . [RFC8919] Ginsberg, L., Psenak, P., Previdi, S., Henderickx, W., and J. Drake, "IS-IS Application-Specific Link Attributes", RFC 8919, DOI 10.17487/RFC8919, October 2020, . 7.2. Informative References [RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams", BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018, . Authors' Addresses Acee Lindem Cisco Systems 301 Midenhall Way Cary, NC 27513 EMail: acee@cisco.com Stephane Litkowski Cisco Systems EMail: slitkows.ietf@gmail.com Yingzhen Qu Futurewei 2330 Central Expressway Santa Clara, CA 95050 USA EMail: yingzhen.qu@futurewei.com Lindem, et al. Expires July 9, 2021 [Page 17]