| Internet-Draft | YANG Data Model for OSPF SRv6 | September 2024 |
| Hu, et al. | Expires 6 March 2025 | [Page] |
This document defines a YANG data model that can be used to configure and manage OSPFv3 Segment Routing over the IPv6 Data Plane.¶
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119 [RFC2119].¶
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 6 March 2025.¶
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.¶
YANG [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 a YANG data model that can be used to configure and manage OSPFv3 SRv6 [RFC9513] and it is an augmentation to the OSPF YANG data model [RFC9129] .¶
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 following terms are defined in [RFC8342]:¶
The following terms are defined in [RFC7950]:¶
Tree diagrams used in this document follow the notation defined in [RFC8340].¶
In this document, names of data nodes, actions, and other data model objects are often used without a prefix, as long as it is clear from the context in which YANG module each name is defined. Otherwise, names are prefixed using the standard prefix associated with the corresponding YANG module, as shown in Table 1.¶
+------------+-----------------------------+-----------------------+ | Prefix |YANG Module | Reference | +------------+-----------------------------+-----------------------+ |ospfv3-e-lsa| ietf-ospfv3-extended-lsa | [RFC9587] | | | | | | ospf | ietf-ospf | [RFC9129] | | | | | | srv6 | ietf-srv6-base | I-D.ietf-spring-srv6 | | | | -yang | | | | | | sr | ietf-segment-routing | [RFC9020] | | | | | | rt | ietf-routing | [RFC8349] | | | | | | yang | ietf-yang-types | [RFC6991] | | | | | | inet | ietf-inet-types | [RFC6991] | +------------+-----------------------------+-----------------------+
This document defines a YANG data model for OSPFv3 SRv6 feature. It is an augmentation of the OSPF base model.¶
The OSPFv3 SRv6 YANG module requires support of OSPF base model [RFC9129] which defines basic OSPF configuration and state and support of OSPFv3 Extended LSAs model [RFC9587].¶
Activation of OSPFv3 SRv6 is done by setting the "enable" leaf to true. This triggers advertisement of SRv6 extensions based on the configuration parameters that have been setup using the base SRv6 module [I-D.ietf-spring-srv6-yang].¶
The SRv6 base module [I-D.ietf-spring-srv6-yang] defines locators. When OSPFv6 SRv6 is enabled, the specified locators are used unless it is enabled to use the default locator. The default locator can be set by using two leafs, i.e.,"default-locator" leaf, "locator-name" leaf.¶
The OSPFv3 SRv6 model augments the fast-reroute container in the OSPF base module with a leaf that enables TI-LFA (Topology Independent LFA) [I-D.ietf-rtgwg-segment-routing-ti-lfa].¶
OSPFv3 SRv6 model augments OSPF module with the micro-loop-avoidance container. This container includes the "srv6-enable" leaf, which activates SRv6 for microloop avoidance.¶
The figure below describes the overall structure of the ospfv3-srv6 YANG module:¶
module: ietf-ospfv3-srv6
augment /rt:routing/rt:control-plane-protocols
/rt:control-plane-protocol/ospf:ospf:
+--rw srv6
| +--rw enable? boolean
| +--rw default-locator? boolean
| +--rw locator-name* -> /rt:routing/srv6:srv6
| /srv6:locators/srv6:locator/srv6:name
| +--rw persistent-end-x-sid? boolean
+--rw micro-loop-avoidance
+--rw srv6-enable? boolean
+--rw srv6-rib-update-delay? uint16
augment /rt:routing/rt:control-plane-protocols
/rt:control-plane-protocol/ospf:ospf
/ospf:fast-reroute:
+--rw srv6-ti-lfa {srv6-ti-lfa}?
+--rw enable? boolean
augment /rt:routing/rt:control-plane-protocols
/rt:control-plane-protocol/ospf:ospf
/ospf:database/ospf:as-scope-lsa-type
/ospf:as-scope-lsas/ospf:as-scope-lsa
/ospf:version/ospf:ospfv3
/ospf:ospfv3/ospf:body:
+--ro srv6-locator
+--ro srv6-locactor-tlv
+--ro route-type? identityref
+--ro algorithm? uint8
+--ro locator-length? uint8
+--ro flags* identityref
+--ro metric? uint32
+--ro locator* inet:ipv6-address-no-zone
+--ro srv6-end-sid
+--ro flags* identityref
+--ro endpoint-func
| +--ro flags* identityref
| +--ro endpoint-func? identityref
| +--ro undefined-endpoint-func? uint16
+--ro sid? srv6-sid-value
+--ro srv6-sid-structure
+--ro lb-length? uint8
+--ro ln-length? uint8
+--ro fun-length? uint8
+--ro arg-length? uint8
augment /rt:routing
/rt:control-plane-protocols/rt:control-plane-protocol
/ospf:ospf/ospf:database
/ospf:as-scope-lsa-type/ospf:as-scope-lsas
/ospf:as-scope-lsa/ospf:version/ospf:ospfv3
/ospf:ospfv3/ospf:body/ospf:router-information:
+--ro srv6-capability
| +--ro flags* identityref
+--ro msd
+--ro max-sl? uint8
+--ro max-end-pop? uint8
+--ro max-h_encap? uint8
+--ro max-end_d? uint8
augment /rt:routing/rt:control-plane-protocols
/rt:control-plane-protocol/ospf:ospf/ospf:areas/ospf:area
/ospf:database/ospf:area-scope-lsa-type/ospf:area-scope-lsas
/ospf:area-scope-lsa/ospf:version/ospf:ospfv3
/ospf:ospfv3/ospf:body/ospfv3-e-lsa:e-router
/ospfv3-e-lsa:e-router-tlvs
/ospfv3-e-lsa:link-tlv:
+--ro srv6-endx-sid
+--ro endpoint-func
| +--ro flags? identityref
| +--ro endpoint-func? identityref
| +--ro undefined-endpoint-func? uint16
+--ro flags? identityref
+--ro algorithm? uint8
+--ro weight? uint8
+--ro sid* srv6-sid-value
+--ro neighbor-router-id? yang:dotted-quad
+--ro srv6-sid-structure
+--ro lb-length? uint8
+--ro ln-length? uint8
+--ro fun-length? uint8
+--ro arg-length? uint8
¶
<CODE BEGINS> file "[email protected]" module ietf-ospfv3-srv6 { yang-version 1.1; namespace "urn:ietf:params:xml:ns:" + "yang:ietf-ospfv3-srv6"; prefix ospfv3-srv6; import ietf-yang-types { prefix yang; reference "RFC 6991: Common YANG Data Types"; } import ietf-routing { prefix rt; reference "RFC 8349: A YANG Data Model for Routing Management (NMDA Version)"; } import ietf-ospfv3-extended-lsa { prefix ospfv3-e-lsa; reference "RFC 9587: YANG Data Model for OSPFv3 Extended Link State Advertisements (LSAs)"; } import ietf-ospf { prefix ospf; reference "RFC 9129: YANG Data Model for the OSPF Protocol"; } import ietf-srv6-base { prefix srv6; } import ietf-inet-types { prefix inet; reference "RFC 6991: Common YANG Data Types"; } import ietf-segment-routing { prefix sr; reference "RFC 9020: YANG Data Model for Segment Routing"; } organization "IETF LSR Working Group"; contact "WG Web: <https://datatracker.ietf.org/group/lsr/> WG List: <mailto:[email protected]> Author: Zhibo Hu <mailto:[email protected]> Author: Xuesong Geng <mailto:[email protected]> Author: Kamran Raza <mailto:[email protected]> Author: Yingzhen Qu <mailto:[email protected]> Author: Acee Lindem <mailto:[email protected]> "; description "The YANG module defines the configuration and operational state for OSPFv3 extensions to support Segment Routing over IPv6 data plane. This YANG model conforms to the Network Management Datastore Architecture (NDMA) as described in RFC 8342. 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 2024-09-02 { description "Initial revision."; reference "RFC XXXX: YANG Data Model for OSPF SRv6"; } /* Identities */ identity SRV6_END_FUNC_TYPE { description "Base identity type for srv6 endpoint function code points."; } identity SRV6_END_FUNC_NO_PSP_USP { base SRV6_END_FUNC_TYPE; description "End (no PSP, no USP)."; } identity SRV6_END_FUNC_PSP { base SRV6_END_FUNC_TYPE; description "End with PSP."; } identity SRV6_END_FUNC_USP { base SRV6_END_FUNC_TYPE; description "END with USP."; } identity SRV6_END_FUNC_PSP_USP { base SRV6_END_FUNC_TYPE; description "END with PSP & USP."; } identity SRV6_END_T_FUNC_NO_PSP_USP { base SRV6_END_FUNC_TYPE; description "End.T (no PSP, no USP)."; } identity SRV6_END_T_FUNC_PSP { base SRV6_END_FUNC_TYPE; description "End.T with PSP."; } identity SRV6_END_T_FUNC_USP { base SRV6_END_FUNC_TYPE; description "End.T with USP."; } identity SRV6_END_T_FUNC_PSP_USP { base SRV6_END_FUNC_TYPE; description "End.T with PSP & USP."; } identity SRV6_END_X_FUNC_NO_PSP_USP { base SRV6_END_FUNC_TYPE; description "End.x (no PSP, no USP)."; } identity SRV6_END_X_FUNC_PSP { base SRV6_END_FUNC_TYPE; description "End.x with PSP."; } identity SRV6_END_X_FUNC_USP { base SRV6_END_FUNC_TYPE; description "End.x with USP."; } identity SRV6_END_X_FUNC_PSP_USP { base SRV6_END_FUNC_TYPE; description "End.x with PSP & USP."; } identity SRV6_END_FUNC_DX6 { base SRV6_END_FUNC_TYPE; description "End.DX6 function."; } identity SRV6_END_FUNC_DT6 { base SRV6_END_FUNC_TYPE; description "End.DT6 function."; } identity SRV6_END_FUNC_OTP { base SRV6_END_FUNC_TYPE; description "END.OTP."; } identity s1-bit { base ospf:ospfv3-lsa-option; description "The S1/S2 bits are dependent on the desired flooding scope for the LSA."; } identity s2-bit { base ospf:ospfv3-lsa-option; description "The S1/S2 bits are dependent on the desired flooding scope for the LSA."; } identity srv6-locator-lsa { base ospf:ospfv3-lsa-type; description "SRv6 Locator LSA - Type TBD"; } identity LOCATOR-ROUTE-TYPE { description "The type of the locator route."; } identity INTRA-AREA-LOCATOR { base LOCATOR-ROUTE-TYPE; description "Intra-Area"; } identity INTER-AREA-LOCATOR { base LOCATOR-ROUTE-TYPE; description "Inter-Area"; } identity AS-EXTERNAL-LOCATOR { base LOCATOR-ROUTE-TYPE; description "AS External"; } identity NSSA-EXTERNAL-LOCATOR { base LOCATOR-ROUTE-TYPE; description "NSSA External"; } identity srv6-capability-bit { description "Base identity for SRv6 capability TLV bits."; } identity o-bit { base srv6-capability-bit; description "O-flag."; reference "RFC 9259: Operations, Administration, and Maintenance (OAM) in Segment Routing over IPv6 (SRv6)"; } identity srv6-end-sid-bit { description "Base identity for SRv6 End SID sub-TLV bits."; } identity srv6-endx-sid-bit { description "Base identity for SRv6 End.X SID sub-TLV bits."; } identity b-bit { base srv6-endx-sid-bit; description "B-flag. Backup flag. If set, the End.X sid is eligible for protection."; } identity s-bit { base srv6-endx-sid-bit; description "S-flag. Set flag. When set, the End.X sid refers to a set of adjacencies (and therefore May be assigned to other adjacencies as well."; } identity p-bit { base srv6-endx-sid-bit; description "P-flag. Persistent flag. When set, the End.X sid is persistently allocated, i.e., the End.x sid value remains consistent across router restart and/or interface flap."; } identity ac-bit { base ospfv3-e-lsa:ospfv3-e-prefix-option; description "When the prefix/SRv6 Locator is configured as anycast, the AC-bit MUST be set. Otherwise, this flag MUST be clear."; reference "draft-ietf-lsr-ospfv3-srv6-extensions"; } /* typedef */ typedef srv6-sid-value { type inet:ipv6-address-no-zone; description "16 Octets encoded sid value."; } /* Features */ feature srv6-ti-lfa { description "Enhance SRv6 FRR with ti-lfa support"; } /* Groupings */ grouping srv6-capabilities { description "SRV6 capability grouping."; container srv6-capability { description "SRv6 capability."; leaf-list flags { type identityref { base srv6-capability-bit; } description "SRv6 Capability TLV flag bits list."; } } } grouping srv6-endpoint-func { description "This group defines srv6 endpoint function"; container endpoint-func { description "SRv6 Endpoint function Descriptor."; leaf-list flags { type identityref { base srv6-end-sid-bit; } description "SRv6 End SID sub-TLV flag bits list. No flags are currently being defined."; } leaf endpoint-func { type identityref { base SRV6_END_FUNC_TYPE; } description "The endpoint function."; } leaf undefined-endpoint-func { type uint16; description "Unknown endpoint func value."; } } } grouping srv6-end-sids { description "This group defines srv6 end sid"; container srv6-end-sid { description "SRv6 Segment Identifier(SID) with Endpoint functions."; leaf-list flags { type identityref { base srv6-end-sid-bit; } description "SRv6 end sid flags."; } uses srv6-endpoint-func; leaf sid { type srv6-sid-value; description "SRV6 sid value."; } uses srv6-sid-structures; } } grouping srv6-sid-structures { description "This group defines SRv6 SID Structure sub-TLV."; container srv6-sid-structure { description "SRv6 SID Structure sub-TLV is used to advertise the length of each individual part of the SRv6 SID as defined in [I-D.ietf-spring-srv6-network-programming]"; leaf lb-length { type uint8; description "SRv6 SID Locator Block length in bits."; } leaf ln-length { type uint8; description "SRv6 SID Locator Node length in bits."; } leaf fun-length { type uint8; description "SRv6 SID Function length in bits."; } leaf arg-length { type uint8; description "SRv6 SID Argument length in bits."; } } } grouping srv6-endx-sids { description "This group defines SRv6 SIDs Associated with Adjacencies including SRv6 End.X SID Sub-TLV and SRv6 LAN End.X SID Sub-TLV."; container srv6-endx-sid { description "SRv6 sids associated with an adjacency."; uses srv6-endpoint-func; leaf-list func-flags { type identityref { base srv6-endx-sid-bit; } description "Flags for SRv6 end x SID."; } leaf algorithm { type uint8; description "Associated algorithm."; } leaf weight { type uint8; description "8 bit field whose value represents the weight of the End.X SID for the purpose of load balancing"; } leaf-list sid { type srv6-sid-value; description "SRV6 sid value."; } leaf neighbor-router-id { type yang:dotted-quad; description "Neighbor router ID.This is only used on LAN adjacencies."; } uses srv6-sid-structures; } } grouping srv6-locactor-tlvs { description "This group defines srv6 locator tlv."; container srv6-locactor-tlv { description "This contains a SRv6 locator tlv."; leaf route-type { type identityref { base LOCATOR-ROUTE-TYPE; } description "The type of the locator route"; } leaf algorithm { type uint8; description "Associated algorithm."; } leaf locator-length { type uint8; description "Carries the length of the Locator prefix as number of bits (1-128)"; } leaf-list flags { type identityref { base ospfv3-e-lsa:ospfv3-e-prefix-option; } description "Flags for srv6 locator tlv."; } leaf metric { type uint32; description "Metric value."; } leaf-list locator { type inet:ipv6-address-no-zone; description "Advertised SRV6 locator."; } uses srv6-end-sids; } } /* Cfg */ augment "/rt:routing/" + "rt:control-plane-protocols/rt:control-plane-protocol" + "/ospf:ospf" { when "../rt:type = 'ospf:ospfv3'" { description "This augment OSPFv3 routing protocol when used"; } description "This augments OSPFv3 protocol configuration with SRv6."; container srv6 { leaf enable { type boolean; default "false"; description "Enables SRv6 protocol extensions."; } leaf default-locator { type boolean; default "false"; description "Enable OSPFv3 segment-routing IPv6 with default Locator."; } leaf-list locator-name { when "not(../default-locator='true')" { description "Only applies to non default locator."; } type leafref { path "/rt:routing/sr:segment-routing/srv6:srv6" + "/srv6:locators/srv6:locator/srv6:name"; } description "Enable OSPFv3 segment-routing IPv6 with specified locator."; } leaf persistent-end-x-sid { type boolean; default "false"; description "Enable the persistent nature of End.X sid"; } description "Configuration about OSPFv3 segment-routing IPv6."; } container micro-loop-avoidance { leaf srv6-enable { type boolean; default "false"; description "Enable SRv6 avoid-microloop.Depend on SR IPv6 Enable."; } leaf srv6-rib-update-delay { type uint16 { range "1000..10000"; } units "ms"; default "5000"; description "Set the route delivery delay for SRv6 avoid-microloop. Depend on SR IPv6 Enable."; } description "Enable OSPFv3 avoid-microloop."; } } augment "/rt:routing/" + "rt:control-plane-protocols/rt:control-plane-protocol" + "/ospf:ospf/ospf:fast-reroute" { when "../../rt:type = 'ospf:ospfv3'" { description "This augment OSPFv3 routing protocol when used"; } description "This augments OSPFv3 IP FRR with IPV6 TILFA."; container srv6-ti-lfa { if-feature "srv6-ti-lfa"; leaf enable { type boolean; description "Enables SRv6 TI-LFA computation."; } description "SRv6 TILFA configuration."; } } /* Database */ augment "/rt:routing/" + "rt:control-plane-protocols/rt:control-plane-protocol/" + "ospf:ospf/ospf:database/" + "ospf:as-scope-lsa-type/ospf:as-scope-lsas/" + "ospf:as-scope-lsa/ospf:version/ospf:ospfv3/" + "ospf:ospfv3/ospf:body" { when "../../../../../../../rt:type = 'ospf:ospfv3'" { description "This augment OSPFv3 routing protocol when used"; } description "This augments OSPFv3 protocol router capability."; container srv6-locator { description "SRv6 Locator LSA."; uses srv6-locactor-tlvs; } } augment "/rt:routing/" + "rt:control-plane-protocols/rt:control-plane-protocol/" + "ospf:ospf/ospf:database/" + "ospf:as-scope-lsa-type/ospf:as-scope-lsas/" + "ospf:as-scope-lsa/ospf:version/ospf:ospfv3/" + "ospf:ospfv3/ospf:body/ospf:router-information" { when "../../../../../../../../rt:type = 'ospf:ospfv3'" { description "This augment OSPFv3 routing protocol when used"; } description "This augments OSPFv3 protocol router capability."; uses srv6-capabilities; uses srv6:srv6-msd-signaled; } augment "/rt:routing/rt:control-plane-protocols" + "/rt:control-plane-protocol/ospf:ospf/ospf:areas/ospf:area" + "/ospf:database/ospf:area-scope-lsa-type" + "/ospf:area-scope-lsas" + "/ospf:area-scope-lsa/ospf:version/ospf:ospfv3" + "/ospf:ospfv3/ospf:body/ospfv3-e-lsa:e-router/" + "ospfv3-e-lsa:e-router-tlvs/" + "ospfv3-e-lsa:link-tlv" { when "../../../../../../../../../../../../rt:type" + "= 'ospf:ospfv3'" { description "This augment OSPFv3 routing protocol when used"; } description "This augments OSPFv3 protocol neighbor."; uses srv6-endx-sids; } /* Notifications */ } <CODE ENDS>¶
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 [RFC8446].¶
The Network Configuration Access Control Model [RFC8341] provides the means to restrict access for particular NETCONF or RESTCONF users to a preconfigured 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 are the subtrees and data nodes and their sensitivity/vulnerability:¶
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 are the subtrees and data nodes and their sensitivity/vulnerability:¶
Qin Wu Huawei Email: [email protected]¶
TBD.¶
The IANA is requested to assign two new URIs from the IETF XML registry ([RFC3688]). Authors are suggesting the following URI:¶
URI: urn:ietf:params:xml:ns:yang:ietf-ospfv3-srv6
Registrant Contact: The IESG.
XML: N/A, the requested URI is an XML namespace
¶
This document also requests one new YANG module name in the YANG Module Names registry ([RFC6020]) with the following suggestion :¶
name: ietf-ospfv3-srv6
namespace: urn:ietf:params:xml:ns:yang:ietf-ospfv3-srv6
prefix: ospfv3-srv6
reference: RFC XXXX¶