module ietf-segment-routing-mpls {

    yang-version 1.1;

    namespace
      "urn:ietf:params:xml:ns:yang:ietf-segment-routing-mpls";

    prefix sr-mpls;

    import ietf-inet-types {
      prefix inet;
      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-routing-types {
      prefix rt-types;
      reference
        "RFC 8294: Common YANG Data Types for the
        	  Routing Area";


    }
    import ietf-segment-routing {
      prefix sr;
      reference
        "RFC 9020: YANG Data Model for Segment Routing";


    }
    import ietf-segment-routing-common {
      prefix sr-cmn;
      reference
        "RFC 9020: YANG Data Model for Segment Routing";


    }

    organization
      "IETF SPRING - SPRING Working Group";

    contact
      "WG Web:   <https://datatracker.ietf.org/wg/spring/>
     WG List:  <mailto:spring@ietf.org>

     Author:    Stephane Litkowski
               <mailto:slitkows.ietf@gmail.com>
     Author:    Yingzhen Qu
               <mailto:yingzhen.qu@futurewei.com>
     Author:    Acee Lindem
               <mailto:acee@cisco.com>
     Author:    Pushpasis Sarkar
               <mailto:pushpasis.ietf@gmail.com>
     Author:    Jeff Tantsura
               <jefftant.ietf@gmail.com>

    ";

    description
      "This YANG module defines a generic configuration model for
     the Segment Routing MPLS data plane.

     This YANG module conforms to the Network Management
     Datastore Architecture (NMDA), as described in RFC 8242.

     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.

     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
     (https://trustee.ietf.org/license-info).

     This version of this YANG module is part of RFC 9020;
     see the RFC itself for full legal notices.";

    reference
      "RFC 9020: YANG Data Model for Segment Routing";


    revision "2021-05-26" {
      description "Initial version";
      reference
        "RFC 9020: YANG Data Model for Segment Routing";

    }


    feature mapping-server {
      description
        "Support for Segment Routing Mapping Server (SRMS).";
      reference
        "RFC 8661: Segment Routing MPLS Interworking
        	  with LDP";

    }

    feature protocol-srgb {
      description
        "Support for per-protocol Segment Routing Global Block
       (SRGB) configuration.";
      reference
        "RFC 8660: Segment Routing with the MPLS
        	  Data Plane";

    }

    typedef system-id {
      type string {
        pattern
          '[0-9A-Fa-f]{4}\.[0-9A-Fa-f]{4}\.[0-9A-Fa-f]{4}';
      }
      description
        "This type defines an IS-IS system-id using a pattern.
       An example system-id is 0143.0438.AEF0.";
    }

    typedef router-or-system-id {
      type union {
        type rt-types:router-id;
        type system-id;
      }
      description
        "OSPF/BGP router-id or IS-IS system ID.";
    }

    grouping sr-control-plane {
      description
        "Defines protocol configuration.";
      container segment-routing {
        description
          "Segment Routing global configuration.";
        leaf enabled {
          type boolean;
          default "false";
          description
            "Enables Segment Routing control-plane protocol
           extensions.";
        }

        container bindings {
          if-feature mapping-server;
          description
            "Control of binding advertisement and reception.";
          container advertise {
            description
              "Control advertisement of local mappings
             in binding TLVs.";
            leaf-list policies {
              type leafref {
                path
                  "/rt:routing/sr:segment-routing/sr-mpls:sr-mpls"
                    + "/sr-mpls:bindings/sr-mpls:mapping-server"
                    + "/sr-mpls:policy/sr-mpls:name";
              }
              description
                "List of binding advertisement policies.";
            }
          }  // container advertise

          leaf receive {
            type boolean;
            default "true";
            description
              "Allow the reception and usage of binding TLVs.";
          }
        }  // container bindings
      }  // container segment-routing
    }  // grouping sr-control-plane

    grouping igp-interface {
      description
        "Grouping for IGP interface configuration.";
      container segment-routing {
        description
          "Container for SR interface configuration.";
        container adjacency-sid {
          description
            "Adjacency SID (Adj-SID) configuration.";
          reference
            "RFC 8660: Segment Routing with the MPLS
            	  Data Plane";

          list adj-sids {
            key "value";
            description
              "List of Adj-SIDs and their configuration.";
            uses sr-cmn:sid-value-type;

            leaf value {
              type uint32;
              description
                "Value of the Adj-SID.";
            }

            leaf protected {
              type boolean;
              default "false";
              description
                "It is used to protect the Adj-SID, e.g., using
               IP Fast Reroute (IPFRR) or MPLS-FRR.";
            }

            leaf weight {
              type uint8;
              description
                "The load-balancing factor over parallel adjacencies.";
              reference
                "RFC 8402: Segment Routing Architecture
                 RFC 8665: OSPF Extensions for Segment Routing
                 RFC 8667: IS-IS Extensions for Segment
                	  Routing";

            }
          }  // list adj-sids

          list advertise-adj-group-sid {
            key "group-id";
            description
              "Control advertisement of S-flag or G-flag.  Enable
             advertisement of a common Adj-SID for parallel
             links.";
            reference
              "RFC 8665: OSPF Extensions for Segment Routing,
              	  Section 6.1
               RFC 8667: IS-IS Extensions for Segment
              	  Routing, Section 2.2.1";

            leaf group-id {
              type uint32;
              description
                "The value is an internal value to identify a
               group-ID. Interfaces with the same group-ID
               will be bundled together.";
            }
          }  // list advertise-adj-group-sid

          leaf advertise-protection {
            type enumeration {
              enum "single" {
                value 0;
                description
                  "A single Adj-SID is associated with the
                 adjacency and reflects the protection
                 configuration.";
              }
              enum "dual" {
                value 1;
                description
                  "Two Adj-SIDs will be associated with the adjacency
                 if the interface is protected.  In this case, one
                 Adj-SID will be advertised with the backup-flag
                 set and the other with the backup-flag clear.  In
                 the case where protection is not configured, a
                 single Adj-SID will be advertised with the
                 backup-flag clear.";
              }
            }
            description
              "If set, the Adj-SID refers to a protected adjacency.";
            reference
              "RFC 8665: OSPF Extensions for Segment Routing,
              	  Section 6.1
               RFC 8667: IS-IS Extensions for Segment
              	  Routing, Section 2.2.1";

          }
        }  // container adjacency-sid
      }  // container segment-routing
    }  // grouping igp-interface

    augment /rt:routing/sr:segment-routing {
      description
        "This augments the routing data model (RFC 8349)
       with Segment Routing (SR) using the MPLS data plane.";
      container sr-mpls {
        description
          "Segment Routing global configuration and
         operational state.";
        container bindings {
          description "List of bindings.";
          container mapping-server {
            if-feature mapping-server;
            description
              "Configuration of mapping-server local entries.";
            list policy {
              key "name";
              description
                "List mapping-server policies.";
              leaf name {
                type string;
                description
                  "Name of the mapping policy.";
              }

              container entries {
                description
                  "IPv4/IPv6 mapping entries.";
                list mapping-entry {
                  key "prefix algorithm";
                  description
                    "Mapping entries.";
                  uses sr-cmn:prefix-sid;
                }  // list mapping-entry
              }  // container entries
            }  // list policy
          }  // container mapping-server

          container connected-prefix-sid-map {
            description
              "Prefix-SID configuration.";
            list connected-prefix-sid {
              key "prefix algorithm";
              description
                "List of mappings of Prefix-SIDs to IPv4/IPv6
               local prefixes.";
              uses sr-cmn:prefix-sid;

              uses sr-cmn:last-hop-behavior;
            }  // list connected-prefix-sid
          }  // container connected-prefix-sid-map

          container local-prefix-sid {
            description
              "Local SID configuration.";
            list local-prefix-sid {
              key "prefix algorithm";
              description
                "List of local IPv4/IPv6 Prefix-SIDs.";
              uses sr-cmn:prefix-sid;
            }  // list local-prefix-sid
          }  // container local-prefix-sid
        }  // container bindings

        container srgb {
          description
            "Global SRGB configuration.";
          uses sr-cmn:srgb;
        }  // container srgb

        container srlb {
          description
            "Segment Routing Local Block (SRLB) configuration.";
          uses sr-cmn:srlb;
        }  // container srlb

        list label-blocks {
          config false;
          description
            "List of label blocks currently in use.";
          leaf lower-bound {
            type uint32;
            description
              "Lower bound of the label block.";
          }

          leaf upper-bound {
            type uint32;
            description
              "Upper bound of the label block.";
          }

          leaf size {
            type uint32;
            description
              "Number of indexes in the block.";
          }

          leaf free {
            type uint32;
            description
              "Number of free indexes in the block.";
          }

          leaf used {
            type uint32;
            description
              "Number of indexes in use in the block.";
          }

          leaf scope {
            type enumeration {
              enum "global" {
                value 0;
                description "Global SID.";
              }
              enum "local" {
                value 1;
                description "Local SID.";
              }
            }
            description
              "Scope of this label block.";
          }
        }  // list label-blocks

        container sid-db {
          config false;
          description
            "List of prefix and SID associations.";
          list sid {
            key "target sid source source-protocol binding-type";
            description "SID binding.";
            leaf target {
              type string;
              description
                "Defines the target of the binding.  It can be a
               prefix or something else.";
            }

            leaf sid {
              type uint32;
              description
                "Index associated with the prefix.";
            }

            leaf algorithm {
              type uint8;
              description
                "Algorithm to be used for the Prefix-SID.";
              reference
                "RFC 8665: OSPF Extensions for Segment Routing
                 RFC 8667: IS-IS Extensions for Segment
                	  Routing
                 RFC 8669: Segment Routing Prefix Segment
                	  Identifier Extensions to BGP";

            }

            leaf source {
              type inet:ip-address;
              description
                "IP address of the router that owns the binding.";
            }

            leaf used {
              type boolean;
              description
                "Indicates if the binding is installed in the
               forwarding plane.";
            }

            leaf source-protocol {
              type leafref {
                path
                  "/rt:routing/rt:control-plane-protocols/"
                    + "rt:control-plane-protocol/rt:name";
              }
              description
                "Routing protocol that owns the binding.";
            }

            leaf binding-type {
              type enumeration {
                enum "prefix-sid" {
                  value 0;
                  description
                    "Binding is learned from a Prefix-SID.";
                }
                enum "binding-tlv" {
                  value 1;
                  description
                    "Binding is learned from a binding TLV.";
                }
              }
              description "Type of binding.";
            }

            leaf scope {
              type enumeration {
                enum "global" {
                  value 0;
                  description "Global SID.";
                }
                enum "local" {
                  value 1;
                  description "Local SID.";
                }
              }
              description "SID scoping.";
            }
          }  // list sid
        }  // container sid-db
      }  // container sr-mpls
    }

    notification segment-routing-srgb-collision {
      description
        "This notification is sent when SRGB blocks received from
       different routers collide.";
      list srgb-collisions {
        description
          "List of SRGB blocks that collide.";
        leaf lower-bound {
          type uint32;
          description
            "Lower value in the block.";
        }

        leaf upper-bound {
          type uint32;
          description
            "Upper value in the block.";
        }

        leaf routing-protocol {
          type leafref {
            path "/rt:routing/rt:control-plane-protocols/rt:control-plane-protocol/rt:name";
          }
          description
            "Routing protocol reference for SRGB collision.";
        }

        leaf originating-rtr-id {
          type router-or-system-id;
          description
            "Originating router ID of this SRGB block.";
        }
      }  // list srgb-collisions
    }  // notification segment-routing-srgb-collision

    notification segment-routing-global-sid-collision {
      description
        "This notification is sent when a new mapping is learned
       containing a mapping where the SID is already used.
       The notification generation must be throttled with at least
       a 5-second gap between notifications.";
      leaf received-target {
        type string;
        description
          "Target received in the router advertisement that caused
         the SID collision.";
      }

      leaf new-sid-rtr-id {
        type router-or-system-id;
        description
          "Router ID that advertised the colliding SID.";
      }

      leaf original-target {
        type string;
        description
          "Target already available in the database with the same SID
         as the received target.";
      }

      leaf original-sid-rtr-id {
        type router-or-system-id;
        description
          "Router ID for the router that originally advertised the
         colliding SID, i.e., the instance in the database.";
      }

      leaf index {
        type uint32;
        description
          "Value of the index used by two different prefixes.";
      }

      leaf routing-protocol {
        type leafref {
          path "/rt:routing/rt:control-plane-protocols/rt:control-plane-protocol/rt:name";
        }
        description
          "Routing protocol reference for colliding SID.";
      }
    }  // notification segment-routing-global-sid-collision

    notification segment-routing-index-out-of-range {
      description
        "This notification is sent when a binding is received
       containing a segment index that is out of the local
       configured ranges.  The notification generation must be
       throttled with at least a 5-second gap between
       notifications.";
      leaf received-target {
        type string;
        description
          "A human-readable string representing the target
         received in the protocol-specific advertisement
         corresponding to the out-of-range index.";
      }

      leaf received-index {
        type uint32;
        description
          "Value of the index received.";
      }

      leaf routing-protocol {
        type leafref {
          path "/rt:routing/rt:control-plane-protocols/rt:control-plane-protocol/rt:name";
        }
        description
          "Routing protocol reference for out-of-range indexed.";
      }
    }  // notification segment-routing-index-out-of-range
  }  // module ietf-segment-routing-mpls