A YANG Data Model for Multicast Source Discovery Protocol (MSDP)
draft-ietf-pim-msdp-yang-09

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 July 24, 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 protocols. 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:
    +--rw msdp!
       +--rw global
       |  +--rw tcp-connection-source?   if:interface-ref 
                {global-tcp-connect-source}?
       |  +--rw default-peer* [peer-addr prefix-policy] 
                {global-default-peer,global-default-peer-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 {global-sa-filter}?
       |  |  +--rw in?    -> /acl:acls/acl/name
       |  |  +--rw out?   -> /acl:acls/acl/name
       |  +--rw sa-limit?                uint32 {global-sa-limit}?
       |  +--rw ttl-threshold?           uint8 {global-ttl-threshold}?
       +--rw peers
       |  +--rw peer* [address]
       |     +--rw address                  inet:ipv4-address
       |     +--rw authentication
       |     |  +--rw (authentication-type)?
       |     |     +--:(key-chain) {peer-key-chain}?
       |     |     |  +--rw key-chain?          key-chain:key-chain-ref
       |     |     +--:(password)
       |     |        +--rw key?                string
       |     |        +--rw crypto-algorithm?   identityref
       |     +--rw enable?                 boolean {peer-admin-enable}?
       |     +--rw tcp-connection-source?  
                   if:interface-ref {peer-tcp-connect-source}?
       |     +--rw description?             string {peer-description}?
       |     +--rw mesh-group?              string
       |     +--rw peer-as?                 inet:as-number {peer-as}?
       |     +--rw sa-filter
       |     |  +--rw in?    -> /acl:acls/acl/name
       |     |  +--rw out?   -> /acl:acls/acl/name
       |     +--rw sa-limit?                uint32 {peer-sa-limit}?
       |     +--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               inet:ipv4-address
             +--ro source-addr         union
             +--ro origin-rp* [rp-address]
             |  +--ro rp-address       inet:ip-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

  rpcs:
    +---x clear-peer
    |  +---w input
    |     +---w peer-address?   inet:ipv4-address
    +---x clear-sa-cache {rpc-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 [RFC6991], [RFC8349], [RFC8343], [RFC8344], [RFC8177], [RFC3618], [RFC8294], [RFC8519].

<CODE BEGINS> file "ietf-msdp@2020-01-21.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 "RFC6991";
     }

     import ietf-inet-types {
       prefix "inet";
       reference "RFC6991";
     }

     import ietf-routing {
       prefix "rt";
       reference "RFC8349";
     }

     import ietf-interfaces {
       prefix "if";
       reference "RFC8343";
     }

     import ietf-ip {
       prefix "ip";
       reference "RFC8344";
     }

     import ietf-key-chain {
       prefix "key-chain";
       reference "RFC8177";
     }

     import ietf-routing-types {
       prefix "rt-types";
       reference "RFC8294";
     }
     
     import ietf-access-control-list {
       prefix acl;
       reference
         "RFC 8519";
     }

     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>";

        description
         "The module defines the YANG model definitions for MSDP 
         [RFC3618].

        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 2020-01-21 {
       description
         "Initial revision.";
       reference
         "RFC XXXX: A YANG Data Model for MSDP.";
     }

     /*
      * Features
      */
     feature global-tcp-connect-source {
       description
         "Support configuration of global tcp connect source.";
     }

     feature global-default-peer {
       description
         "Support configuration of global default peer.";
     }

     feature global-default-peer-policy {
       description
         "Support policy configuration of global default peer.";
     }

     feature global-sa-filter {
       description
         "Support configuration of global SA filter.";
     }

     feature global-sa-limit {
       description
         "Support configuration of global limit on SA entries.";
     }

     feature global-ttl-threshold {
       description
         "Support configuration of global TTL threshold.";
     }

     feature rpc-clear-sa-cache {
       description
         "Support the RPC to clear SA cache.";
     }

     feature peer-admin-enable {
       description
         "Support configuration of peer administrative enabling.";
     }

     feature peer-as {
       description
         "Support configuration of peer AS number.";
     }

     feature peer-tcp-connect-source {
       description
         "Support configuration of peer tcp connect source.";
     }

     feature peer-description {
       description
         "Support configuration of peer description.";
     }

     feature peer-key-chain {
       description
         "Support configuration of peer key-chain.";
     }

     feature peer-password {
       description
         "Support configuration of peer password.";
     }

     feature peer-sa-limit {
       description
         "Support configuration of per peer limit on SA entries.";
     }

     /*
      * Groupings
      */
     grouping authentication-container {
       description
         "Authentication attributes.";
       container authentication {
         description
           "A container defining authentication attributes.";
         choice authentication-type {
           case key-chain {
             if-feature peer-key-chain;
             leaf key-chain {
               type key-chain:key-chain-ref;
               description
                 "Reference to a key-chain. The key-chain model is 
                  defined in RFC8177.";
             }
           }
           case password {
             leaf key {
               type string;
               description
                 "This leaf describes the authentication key.";
             }
             leaf crypto-algorithm {
               type identityref {
                 base key-chain:crypto-algorithm;
               }
               description
                 "Cryptographic algorithm associated with key.";
             }
           }
           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" {
           description
             "The interface must have IPv4 enabled.";
         }
         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-connection-source

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

       uses tcp-connect-source {
         if-feature global-tcp-connect-source;
       }
       list default-peer {
         if-feature global-default-peer;
         if-feature global-default-peer-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" {
             description
               "The interface must have IPv4 enabled.";
           }
           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 {
         if-feature global-sa-filter;
       }
       leaf sa-limit {
         if-feature global-sa-limit;
         type uint32;
         description
           "A limit on the number of SA entries accepted. 
            By default, there is no limit.";
       }
       uses ttl-threshold {
         if-feature global-ttl-threshold;
       }
     } // global-config-attributes

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

       uses authentication-container;
       leaf enable {
         if-feature peer-admin-enable;
         type boolean;
         description
           "'true' if peer is enabled;
            'false' if peer is disabled.";
       }
       uses tcp-connect-source {
         if-feature peer-tcp-connect-source;
       }
       leaf description {
         if-feature peer-description;
         type string;
         description
           "The peer description.";
       }
       leaf mesh-group {
         type string;
         description
           "Configure this peer to be a member of a mesh group";
       }
       leaf peer-as {
         if-feature peer-as;
         type inet:as-number;
         description
           "Peer's autonomous system number (ASN). Using peer-as to 
            do verification can provide more controlled ability.";
       }
       uses sa-filter-container;
       leaf sa-limit {
         if-feature peer-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.";
         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
           "RFC3618: Multicast Source Discovery Protocol (MSDP).";
       }
       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.";
           }
         } // statistics-error

         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.";
           }
         } // statistics-queue

         container received {
           description "Received message counters.";
           uses statistics-sent-received;
         }
         container sent {
           description "Sent message counters.";
           uses statistics-sent-received;
         }
       } // statistics-container
     } // 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" {
       description
         "MSDP augmentation to routing instance. This augmentation 
          is only valid for a routing protocol instance of MSDP.";

       container msdp {
         presence "Container for MSDP protocol.";
         description
           "MSDP configuration 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;
           } // peer
         } // peers

         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 inet:ipv4-address;
               description "The group address of this SA cache.";
             }
             leaf source-addr {
               type union {
                 type enumeration {
                   enum '*' {
                     description "Any source address.";
                   }
                 }
                 type inet:ipv4-address;
               }
               description "Source IPv4 address.";
             }
             list origin-rp {
               key "rp-address";
               description "Origin RP address.";
               leaf rp-address {
                 type inet:ip-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 "The duration time of receiving this 
                              SA cache.";
               }
               leaf expire {
                 type uint32;
                 units seconds;
                 description "The duration time since this SA cache 
                              expires.";
               }
               leaf holddown-interval {
                 type uint32;
                 units seconds;
                 description "Hold-down timer value for SA 
                              forwarding.";
               }
               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.";
               }
             } // sa-cache-state-attributes
           } // entry
         } // sa-cache
       } // msdp
     } // augment

     /*
      * RPCs
      */
     rpc clear-peer {
       description
         "Clears the TCP connection to the peer.";
       input {
         leaf peer-address {
           type inet:ipv4-address;
           description
             "Address of peer to be cleared. If this is not 
              provided then all peers are cleared.";
         }
       }
     }

     rpc clear-sa-cache {
       if-feature rpc-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.";
           }
         } // s-g
         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.";
         }
       }
     }
   }
<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

The IANA is requested to assign one new URIs 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