A YANG Data Model for Multicast Source Discovery Protocol (MSDP)
draft-ietf-pim-msdp-yang-13

Abstract

This document defines a YANG data model for the configuration and management of Multicast Source Discovery Protocol (MSDP) Protocol.

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 August 8, 2020.

Copyright Notice

Copyright (c) 2020 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 the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License.

Table of Contents

• 1. Introduction
• 1.1. Terminology
• 1.2. Conventions Used in This Document
• 1.3. Tree Diagrams
• 1.4. Prefixes in Data Node Names
• 2. Design of the Data Model
• 2.1. Scope of Model
• 2.2. Specification
• 3. Module Structure
• 3.1. MSDP Configuration
• 3.2. MSDP State
• 3.3. MSDP RPC
• 4. MSDP YANG Model
• 5. Security Considerations
• 6. IANA Considerations
• 7. Contributors
• 8. Acknowledgement
• 9. References
• 9.1. Normative References
• 9.2. Informative References
• Authors' Addresses

1. Introduction

[RFC3618] introduces the protocol definition of MSDP. This document defines a YANG data model that can be used to configure and manage the MSDP protocol. The operational state data and statistics can also be retrieved by this model.

This model is designed to be used along with other multicast YANG models such as PIM [I-D.ietf-pim-yang], which are not covered in this document.

1.1. Terminology

The terminology for describing YANG data models is found in [RFC6020] and [RFC7950], including:

• augment
• data model
• data node
• identity
• module

The following abbreviations are used in this document and the defined model:

MSDP: Multicast Source Discovery Protocol [RFC3618].

SA: Source-Active [RFC3618].

1.2. Conventions Used in This Document

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.

1.3. Tree Diagrams

Tree diagrams used in this document follow the notation defined in [RFC8340].

1.4. Prefixes in Data Node Names

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.

2. Design of the Data Model

2.1. Scope of Model

The model covers MSDP [RFC3618].

This model can be used to configure and manage MSDP protocol. The operational state data and statistics can be retrieved by this model. Even though no protocol-specific notifications are defined in this model, the subscription and push mechanism defined in [RFC8639] and [RFC8641] can be implemented by the user to subscribe to notifications on the data nodes in this model.

The model contains all the basic configuration parameters to operate the protocol. Depending on the implementation choices, some systems may not allow some of the advanced parameters to be configurable. The occasionally implemented parameters are modeled as optional features in this model. This model can be extended, and it has been structured in a way that such extensions can be conveniently made.

2.2. Specification

The configuration data nodes cover global configuration attributes and per peer configuration attributes. The state data nodes include global, per peer, and source-active information. The container "msdp" is the top level container in this data model. The presence of this container is expected to enable MSDP protocol functionality. No notification is defined in this model.

3. Module Structure

This model imports and augments the ietf-routing YANG model defined in [RFC8349]. Both configuration data nodes and state data nodes of [RFC8349] are augmented.

The YANG data model defined in this document conforms to the Network Management Datastore Architecture (NMDA) [RFC8342]. The operational state data is combined with the associated configuration data in the same hierarchy [RFC8407].

module: ietf-msdp
  augment /rt:routing/rt:control-plane-protocols
            /rt:control-plane-protocol:
    +--rw msdp
       +--rw global
       |  +--rw tcp-connection-source?   if:interface-ref
       |  +--rw default-peer* [peer-addr prefix-policy]
                              {filter-policy}?
       |  |  +--rw peer-addr        -> ../../../peers/peer/address
       |  |  +--rw prefix-policy    -> /acl:acls/acl/name
       |  +--rw originating-rp
       |  |  +--rw interface?   if:interface-ref
       |  +--rw sa-filter
       |  |  +--rw in?    -> /acl:acls/acl/name
       |  |  +--rw out?   -> /acl:acls/acl/name
       |  +--rw sa-limit?                uint32
       |  +--rw ttl-threshold?           uint8
       +--rw peers
       |  +--rw peer* [address]
       |     +--rw address                  inet:ipv4-address
       |     +--rw authentication {peer-authentication}?
       |     |  +--rw (authentication-type)?
       |     |     +--:(key-chain)
       |     |     |  +--rw key-chain?          key-chain:key-chain-ref
       |     |     +--:(password)
       |     |        +--rw key?                string
       |     |        +--rw crypto-algorithm?   identityref
       |     +--rw enabled?                 boolean
       |     +--rw tcp-connection-source?   if:interface-ref
       |     +--rw description?             string
       |     +--rw mesh-group?              string
       |     +--rw peer-as?                 inet:as-number 
                                            {peer-as-verification}?
       |     +--rw sa-filter
       |     |  +--rw in?    -> /acl:acls/acl/name
       |     |  +--rw out?   -> /acl:acls/acl/name
       |     +--rw sa-limit?                uint32
       |     +--rw timer
       |     |  +--rw connect-retry-interval?   uint16
       |     |  +--rw holdtime-interval?        uint16
       |     |  +--rw keepalive-interval?       uint16
       |     +--rw ttl-threshold?           uint8
       |     +--ro session-state?           enumeration
       |     +--ro elapsed-time?            uint32
       |     +--ro connect-retry-expire?    uint32
       |     +--ro hold-expire?             uint16
       |     +--ro is-default-peer?         boolean
       |     +--ro keepalive-expire?        uint16
       |     +--ro reset-count?             uint32
       |     +--ro statistics
       |        +--ro discontinuity-time?   yang:date-and-time
       |        +--ro error
       |        |  +--ro rpf-failure?   uint32
       |        +--ro queue
       |        |  +--ro size-in?    uint32
       |        |  +--ro size-out?   uint32
       |        +--ro received
       |        |  +--ro keepalive?      yang:counter64
       |        |  +--ro notification?   yang:counter64
       |        |  +--ro sa-message?     yang:counter64
       |        |  +--ro sa-response?    yang:counter64
       |        |  +--ro sa-request?     yang:counter64
       |        |  +--ro total?          yang:counter64
       |        +--ro sent
       |           +--ro keepalive?      yang:counter64
       |           +--ro notification?   yang:counter64
       |           +--ro sa-message?     yang:counter64
       |           +--ro sa-response?    yang:counter64
       |           +--ro sa-request?     yang:counter64
       |           +--ro total?          yang:counter64
       +--ro sa-cache
       |  +--ro entry* [group source-addr]
       |     +--ro group               
                     rt-types:ipv4-multicast-group-address
       |     +--ro source-addr         
                     rt-types:ipv4-multicast-source-address
       |     +--ro origin-rp* [rp-address]
       |     |  +--ro rp-address       inet:ipv4-address
       |     |  +--ro is-local-rp?     boolean
       |     |  +--ro sa-adv-expire?   uint32
       |     +--ro state-attributes
       |        +--ro up-time?             uint32
       |        +--ro expire?              uint32
       |        +--ro holddown-interval?   uint32
       |        +--ro peer-learned-from?   inet:ipv4-address
       |        +--ro rpf-peer?            inet:ipv4-address
       +---x clear-peer
       |  +---w input
       |     +---w (peer)
       |        +--:(peer-address)
       |        |  +---w peer-address?   inet:ipv4-address
       |        +--:(all)
       |           +---w all-peers?      empty
       +---x clear-sa-cache
          +---w input
             +---w entry!
             |  +---w group          
                        rt-types:ipv4-multicast-group-address
             |  +---w source-addr?   
                        rt-types:ipv4-multicast-source-address
             +---w peer-address?   inet:ipv4-address
             +---w peer-as?        inet:as-number
            

3.1. MSDP Configuration

MSDP configurations require peer configurations. Several peers may be configured in a mesh-group. The Source-Active information may be filtered by peers.

The configuration modeling branch is composed of MSDP global and peer configurations. The two parts are the most important parts of MSDP.

Besides the fundamental features of MSDP protocol, several optional features are included in the model. These features help the control of MSDP protocol. The peer features and SA features make the deployment and control easier. The connection parameters can be used to control the TCP connection because MSDP protocol is based on TCP. The authentication features make the protocol more secure. The filter features selectively allow operators to prevent SA information from being forwarded to peers.

3.2. MSDP State

MSDP states are composed of MSDP global state, MSDP peer state, statistics information and SA cache information. The statistics information and SA cache information helps the operator to retrieve the protocol condition.

3.3. MSDP RPC

The RPC part is used to define some useful and ordinary operations of protocol management. Network managers can delete all the information from a given peer by using the clear-peer rpc. And network managers can delete a given SA cache information by clear-sa-cache rpc.

4. MSDP YANG Model

This module references [RFC3618], [RFC4271], [RFC6991], [RFC8177], [RFC8343], [RFC8344], [RFC8349], [RFC8294], [RFC8519].

<CODE BEGINS> file "ietf-msdp@2020-01-29.yang"
module ietf-msdp {

  yang-version 1.1;

  namespace "urn:ietf:params:xml:ns:yang:ietf-msdp";
  prefix msdp;

  import ietf-yang-types {
    prefix "yang";
    reference "RFC 6991: Common YANG Data Types";
  }

  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-interfaces {
    prefix "if";
    reference "RFC 8343: A YANG Data Model for Interface Management";
  }

  import ietf-ip {
    prefix "ip";
    reference "RFC 8344: A YANG Data Model for IP Management";
  }

  import ietf-key-chain {
    prefix "key-chain";
    reference "RFC 8177: YANG Data Model for Key Chains";
  }

  import ietf-routing-types {
    prefix "rt-types";
    reference "RFC 8294: Common YANG Data Types for the Routing 
                         Area";
  }
   
  import ietf-access-control-list {
    prefix acl;
    reference
      "RFC 8519: YANG Data Model for Network Access Control Lists 
                 (ACLs)";
  }

  organization
    "IETF PIM (Protocols for IP Multicast) Working Group";

  contact
    "WG Web:   <http://tools.ietf.org/wg/pim/>
     WG List:  <mailto:pim@ietf.org>

     Editor:   Xufeng Liu
               <mailto:xufeng.liu.ietf@gmail.com>

     Editor:   Zheng Zhang
               <mailto:zzhang_ietf@hotmail.com>

     Editor:   Anish Peter
               <mailto:anish.ietf@gmail.com>

     Editor:   Mahesh Sivakumar
               <mailto:sivakumar.mahesh@gmail.com>

     Editor:   Feng Guo
               <mailto:guofeng@huawei.com>

     Editor:   Pete McAllister
               <mailto:pete.mcallister@metaswitch.com>";

  // RFC Ed.: replace XXXX with actual RFC number and remove
  // this note
               
  description
    "The module defines the YANG model definitions for 
     Multicast Source Discovery Protocol (MSDP).

     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 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 2020-02-05 {
    description
      "Initial revision.";
    reference
      "RFC XXXX: A YANG Data Model for MSDP.";
  }
   
  /*
   * Features
   */
   
  feature filter-policy {
    description
      "Support policy configuration of peer/message filtering.";
    reference
      "RFC 8519: YANG Data Model for Network Access Control 
       Lists (ACLs)";
  }

  feature peer-as-verification {
    description
      "Support configuration of peer AS number.";
    reference
      "RFC 4271: A Border Gateway Protocol 4 (BGP-4)";
  }

  feature peer-authentication {
    description
      "Support configuration of peer authentication.";
    reference
      "RFC 8177: YANG Data Model for Key Chains.";
  }

  /*
   * Identities
   */

  identity msdp {
    base rt:control-plane-protocol;
    description "Identity for the Multicast Source Discovery 
                 Protocol (MSDP).";
    reference
      "RFC 3618: Multicast Source Discovery Protocol (MSDP)";
  }
   
  /*
   * Groupings
   */
  grouping authentication-container {
    description
      "Authentication attributes.";
    container authentication {
      if-feature peer-authentication;
      description
        "A container defining authentication attributes.";
      choice authentication-type {
        case key-chain {
          leaf key-chain {
            type key-chain:key-chain-ref;
            description
              "Reference to a key-chain.";
            reference
              "RFC 8177: YANG Data Model for Key Chains.";
          }
        }
        case password {
          leaf key {
            type string;
            description
              "This leaf describes the authentication key.";
            reference
              "RFC 8177: YANG Data Model for Key Chains.";
          }
          leaf crypto-algorithm {
            type identityref {
              base key-chain:crypto-algorithm;
            }
            description
              "Cryptographic algorithm associated with key.";
            reference
              "RFC 8177: YANG Data Model for Key Chains.";
          }
        }
        description
          "Choice of authentication.";
      }
    }
  } // authentication-container

  grouping tcp-connect-source {
    description 
      "Attribute to configure peer TCP connection source.";
    leaf tcp-connection-source {
      type if:interface-ref;
      must "/if:interfaces/if:interface[if:name = current()]/"
        + "ip:ipv4/ip:enabled != 'false'" {
        error-message "The interface must have IPv4 enabled.";
        description
          "The interface must have IPv4 enabled.";
        reference 
          "RFC 8343: A YANG Data Model for Interface Management";
      }
      description
        "The interface is to be the source for the TCP 
         connection. It is a reference to an entry in the global 
         interface list.";
    }
  } // tcp-connect-source

  grouping global-config-attributes {
    description "Global MSDP configuration.";

    uses tcp-connect-source;

    list default-peer {
      if-feature filter-policy;
      key "peer-addr prefix-policy";

      description
        "The default peer accepts all MSDP SA messages.
         A default peer is needed in topologies where MSDP peers 
         do not coexist with BGP peers. The reverse path 
         forwarding (RPF) check on SA messages can fail, and no 
         SA messages are accepted. In these cases, you can configure
         the peer as a default peer and bypass RPF checks.";

      leaf peer-addr {
        type leafref {
          path "../../../peers/peer/address";
        }
        mandatory true;
        description
          "Reference to a peer that is in the peer list.";
      }
      leaf prefix-policy {
        type leafref {
          path "/acl:acls/acl:acl/acl:name";
        }
        description
          "If specified, only those SA entries whose RP is 
           permitted in the prefix list are allowed;
           if not specified, all SA messages from the default 
           peer are accepted.";
        reference
          "RFC 8519: YANG Data Model for Network Access Control 
           Lists (ACLs)";
      }
    } // default-peer

    container originating-rp {
      description
        "The container of Originating RP.";
      leaf interface {
        type if:interface-ref;
        must "/if:interfaces/if:interface[if:name = current()]/"
              + "ip:ipv4/ip:enabled != 'false'" {
          error-message "The interface must have IPv4 enabled.";
          description
            "The interface must have IPv4 enabled.";
          reference 
            "RFC 8343: A YANG Data Model for Interface Management";
        }
        description
          "Reference to an entry in the global interface
           list.
           IP address of the interface used in the RP field of 
           an SA message entry. When Anycast RPs are used, all 
           RPs use the same IP address. This parameter can be 
           used to define a unique IP address for the RP of each 
           MSDP peer.
           By default, the software uses the RP address of the
           local system.";
      }
    } // originating-rp

    uses sa-filter-container;
    
    leaf sa-limit {
      type uint32;
      description
        "A limit on the number of SA entries accepted. 
         By default, there is no limit.";
    }
    uses ttl-threshold;
  } // global-config-attributes

  grouping peer-config-attributes {
    description "Per peer configuration for MSDP.";

    uses authentication-container;
    leaf enabled {
      type boolean;
      description
        "'true' if peer is enabled;
         'false' if peer is disabled.";
    }
    uses tcp-connect-source;
    
    leaf description {
      type string;
      description
        "The peer description.";
    }
    leaf mesh-group {
      type string;
      description
        "Configure this peer to be a member of a mesh group";
      reference
        "RFC 3618: Multicast Source Discovery Protocol (MSDP), 
                   section 10.2.";
    }
    leaf peer-as {
      if-feature peer-as-verification;
      type inet:as-number;
      description
        "Peer's autonomous system number (ASN). Using peer-as to 
         do verification can provide more controlled ability.
         If the AS number is the same as the local AS, then the 
         peer is within the same domain; otherwise, this peer is 
         external to the domain. Like the definition and usage 
         in BGP protocol.";
      reference
        "RFC 4271: A Border Gateway Protocol 4 (BGP-4)";
    }
    uses sa-filter-container;
    leaf sa-limit {
      type uint32;
      description
        "A limit on the number of SA entries accepted from this 
         peer. By default, there is no limit.";
    }
    container timer {
      description "Timer attributes.";
      reference
        "RFC 3618: Multicast Source Discovery Protocol (MSDP), 
                   section 5.";
      leaf connect-retry-interval {
        type uint16;
        units seconds;
        default 30;
        description "Peer timer for connect-retry. 
                     By default, MSDP peers wait 30 seconds after
                     session is reset.";
      }
      leaf holdtime-interval {
        type uint16 {
          range "3..65535";
        }
        units seconds;
        must "(../keepalive-interval and . > ../keepalive-interval) " 
          + "or (not(../keepalive-interval) and . > 60)" {
          error-message "The keep alive interval must be "
                        + "smaller than the hold time interval";
        }
        default 75;
        description "The SA hold down period of this MSDP peer.";
      }
      leaf keepalive-interval {
        type uint16 {
            range "1..65535";
        }
        units seconds;
        must "(../holdtime-interval and . < ../holdtime-interval) " 
          + "or (not(../holdtime-interval) and . < 75)" {
          error-message "The keep alive interval must be "
                    + "smaller than the hold time interval";
        }
        default 60;
        description "The keepalive timer of this MSDP peer.";
      }
    } // timer
    uses ttl-threshold;
  } // peer-config-attributes

  grouping peer-state-attributes {
    description "Per peer state attributes for MSDP.";

    leaf session-state {
      type enumeration {
        enum disabled  {
          description "Disabled.";
        }
        enum inactive {
          description "Inactive.";
        }
        enum listen {
          description "Listen.";
        }
        enum connecting {
          description "Connecting.";
        }
        enum established {
          description "Established.";
        }
      }
      config false;
      description
        "Peer session state.";
      reference
        "RFC 3618: Multicast Source Discovery Protocol (MSDP), 
                   section 11.";
    }
    leaf elapsed-time {
      type uint32;
      units seconds;
      config false;
      description "Elapsed time for being in a state.";
    }
    leaf connect-retry-expire {
      type uint32;
      units seconds;
      config false;
      description "Connect retry expire time of peer connection.";
    }
    leaf hold-expire {
      type uint16;
      units seconds;
      config false;
      description "Hold expire time of peer connection.";
    }
    leaf is-default-peer {
      type boolean;
      config false;
      description "'true' if this peer is a default peer.";
    }
    leaf keepalive-expire {
      type uint16;
      units seconds;
      config false;
      description "Keepalive expire time of this peer.";
    }
    leaf reset-count {
      type uint32;
      config false;
      description "The reset count of this peer.";
    }

    container statistics {
      config false;
      description
        "A container defining statistics attributes.";

      leaf discontinuity-time {
        type yang:date-and-time;
        description
          "The time on the most recent occasion at which any one
          or more of the statistic counters suffered a
          discontinuity. If no such discontinuities have occurred
          since the last re-initialization of the local
          management subsystem, then this node contains the time
          the local management subsystem re-initialized itself.";
      }

      container error {
        description
          "A grouping defining error statistics attributes.";
        leaf rpf-failure {
          type uint32;
          description "Number of RPF failures.";
        }
      }

      container queue {
        description
          "A container includes queue statistics attributes.";
        leaf size-in {
          type uint32;
          description
            "The size of the input queue.";
        }
        leaf size-out {
          type uint32;
          description
            "The size of the output queue.";
        }
      }

      container received {
        description "Received message counters.";
        uses statistics-sent-received;
      }
      container sent {
        description "Sent message counters.";
        uses statistics-sent-received;
      }
    } // statistics
  } // peer-state-attributes

  grouping sa-filter-container {
    description "A container defining SA filters.";
    container sa-filter {
      description
        "Specifies an access control list (ACL) to filter source
         active (SA) messages coming in to or going out of the 
         peer.";
      leaf in {
        type leafref {
          path "/acl:acls/acl:acl/acl:name";
        }
        description
          "Filters incoming SA messages only. 
           The value is the name to uniquely identify a 
           policy that contains one or more rules used to 
           accept or reject MSDP SA messages.
           If the policy is not specified, all MSDP SA messages are 
           accepted.";
        reference
          "RFC 8519: YANG Data Model for Network Access Control 
           Lists (ACLs)";
      }
      leaf out {
        type leafref {
          path "/acl:acls/acl:acl/acl:name";
        }
        description
          "Filters outgoing SA messages only.
           The value is the name to uniquely identify a 
           policy that contains one or more rules used to 
           accept or reject MSDP SA messages.
           If the policy is not specified, all MSDP SA messages are 
           sent.";
        reference
          "RFC 8519: YANG Data Model for Network Access Control 
           Lists (ACLs)";
      }
    } // sa-filter
  } // sa-filter-container

  grouping ttl-threshold {
    description "Attribute to configure TTL threshold.";
    leaf ttl-threshold {
      type uint8 {
        range 1..255;
      }
      description "Maximum number of hops data packets can 
                   traverse before being dropped.";
    }
  } // ttl-threshold

  grouping statistics-sent-received {
    description
      "A grouping defining sent and received statistics attributes.";
    leaf keepalive {
      type yang:counter64;
      description
        "The number of keepalive messages.";
    }
    leaf notification {
      type yang:counter64;
      description
        "The number of notification messages.";
    }
    leaf sa-message {
      type yang:counter64;
      description
        "The number of SA messages.";
    }
    leaf sa-response {
      type yang:counter64;
      description
        "The number of SA response messages.";
    }
    leaf sa-request {
      type yang:counter64;
      description
        "The number of SA request messages.";
    }
    leaf total {
      type yang:counter64;
      description
        "The number of total messages.";
    }
  } // statistics-sent-received

  /*
   * Data nodes
   */
  augment "/rt:routing/rt:control-plane-protocols/"
         + "rt:control-plane-protocol" {
    when "derived-from-or-self(rt:type, 'msdp:msdp')" {
      description
        "This augmentation is only valid for a routing protocol 
         instance of MSDP.";
    }
    description 
      "MSDP augmentation to routing control-plane protocol 
       configuration and state.";
    container msdp {
      description
        "MSDP configuration and operational state data.";

      container global {
        description
          "Global attributes.";
        uses global-config-attributes;
      }

      container peers {
        description
          "Containing a list of peers.";
        list peer {
          key "address";
          description
            "List of MSDP peers.";
          leaf address {
            type inet:ipv4-address;
            description
              "The address of the peer";
          }
          uses peer-config-attributes;
          uses peer-state-attributes;
        }
      }

      container sa-cache {
        config false;
        description
          "The SA cache information.";
        list entry {
          key "group source-addr";
          description "A list of SA cache entries.";
          leaf group {
            type rt-types:ipv4-multicast-group-address;
            description "The group address of this SA cache.";
          }
          leaf source-addr {
            type rt-types:ipv4-multicast-source-address;
            description "Source IPv4 address.";
          }
          list origin-rp {
            key "rp-address";
            description "Origin RP address.";
            leaf rp-address {
              type inet:ipv4-address;
              description "The RP address.";
            }
            leaf is-local-rp {
              type boolean;
              description "The RP is local.";
            }
            leaf sa-adv-expire {
              type uint32;
              units seconds;
              description
                "The remaining time duration before expiration 
                 of the periodic SA advertisement timer on a 
                 local RP.";
            }
          }

          container state-attributes {
            description "SA cache state attributes for MSDP.";

            leaf up-time {
              type uint32;
              units seconds;
              description "Indicates the time when this SA entry is 
                           created in the cache. MSDP is a periodic 
                           protocol, the up-time value can be 
                           used to check the state of SA cache.";
            }
            leaf expire {
              type uint32;
              units seconds;
              description "Indicates the time when this SA entry in 
                           the cache times out. MSDP is a periodic 
                           protocol, the expire value can be 
                           used to check the state of SA cache.";
            }
            leaf holddown-interval {
              type uint32;
              units seconds;
              description "Hold-down timer value for SA 
                           forwarding.";
              reference
                "RFC 3618: Multicast Source Discovery Protocol 
                           (MSDP), section 5.3.";
            }
            leaf peer-learned-from {
              type inet:ipv4-address;
              description
                "The address of the peer that we learned this 
                 SA from.";
            }
            leaf rpf-peer {
              type inet:ipv4-address;
              description 
                "The address is used to find the SA's 
                 originating RP.";
            }
          } // state-attributes
        } // entry
      } // sa-cache

      /*
       * Actions
       */
      action clear-peer {
        description
          "Clears the TCP connection to the peer.";
        input {
          choice peer {
            mandatory true;
            description
              "Address of peer to be cleared.";
            case peer-address {
              leaf peer-address {
                type inet:ipv4-address;
                description
                  "Address of peer to be cleared.";
              }
            }
            case all {
              leaf all-peers {
                type empty;
                description
                  "All peers' TCP connection are cleared.";
              }
            }
          }
        }
      } // clear-peer

      action clear-sa-cache {
        description
          "Clears MSDP source active (SA) cache entries.";
        input {
          container entry {
            presence "If a particular entry is cleared.";
            description
              "The SA cache (S,G) or (*,G) entry to be cleared. If 
               this is not provided, all entries are cleared.";
            leaf group {
              type rt-types:ipv4-multicast-group-address;
              mandatory true;
              description "The group address";
            }
            leaf source-addr {
              type rt-types:ipv4-multicast-source-address;
              description 
                "Address of multicast source to be cleared. If this 
                 is not provided then all entries related to the 
                 given group are cleared.";
            }
          }
          leaf peer-address {
            type inet:ipv4-address;
            description
              "Peer IP address from which MSDP SA cache entries have 
               been learned. If this is not provided, entries learned 
               from all peers are cleared.";
          }
          leaf peer-as {
            type inet:as-number;
            description
              "ASN from which MSDP SA cache entries have been learned.
               If this is not provided, entries learned from all AS's
               are cleared.";
          }
        }
      } // clear-sa-cache
    } // msdp
  } // augment
}
<CODE ENDS>
            

5. Security Considerations

The YANG module specified in this document defines 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 NETCONF 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 this YANG module 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:

Under /rt:routing/rt:control-plane-protocols/msdp,

msdp:global

• This subtree specifies the configuration for the MSDP attributes at the global level. Modifying the configuration can cause MSDP default peers to be deleted or reconstructed, and the SA's unexpected filtering.

msdp:peers

• This subtree specifies the configuration for the MSDP attributes at the peer level. The modification configuration will allow the unexpected MSDP peer establishment and unexpected SA information learning and advertisement.
• The "key" field is also a sensitive readable configuration, the unauthorized reading function may lead to the password leaking. The modification will allow the unexpected peer reconstruction.

Some of the readable data nodes in this YANG module 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. These are the subtrees and data nodes and their sensitivity/vulnerability:

/rt:routing/rt:control-plane-protocols/msdp,

Unauthorized access to any data node of the above subtree can disclose the operational state information of MSDP on this device.

Some of the RPC operations in this YANG module may be considered sensitive or vulnerable in some network environments. It is thus important to control access to these operations. These are the operations and their sensitivity/vulnerability:

/rt:routing/rt:control-plane-protocols/msdp:clear-peer,

/rt:routing/rt:control-plane-protocols/msdp:clear-sa-cache,

Unauthorized access to any of the above action operations can reconstruct the MSDP peers or delete SA records on this device.

6. IANA Considerations

RFC Ed.: Please replace all occurrences of 'XXXX' with the actual RFC number (and remove this note).

The IANA is requested to assign one new URI from the IETF XML registry [RFC3688]. Authors are suggesting the following URI:

URI: urn:ietf:params:xml:ns:yang:ietf-msdp

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-msdp

namespace: urn:ietf:params:xml:ns:yang:ietf-msdp

prefix: msdp

reference: RFC XXXX

7. Contributors

The authors would like to thank Yisong Liu (liuyisong@huawei.com), Benchong Xu (xu.benchong@zte.com.cn), Tanmoy Kundu (tanmoy.kundu@alcatel-lucent.com) for their valuable contributions.

8. Acknowledgement

The authors would like to thank Stig Venaas, Jake Holland for their valuable comments and suggestions.

9. References

9.1. Normative References

9.2. Informative References

Authors' Addresses