





Internet Engineering Task Force (IETF)                      M. Bjorklund
Request for Comments: 7277                                Tail-f Systems
Category: Standards Track                                      June 2014
ISSN: 2070-1721


                  A YANG Data Model for IP Management

Abstract

   This document defines a YANG data model for management of IP
   implementations.  The data model includes configuration data and
   state data.

Status of This Memo

   This is an Internet Standards Track document.

   This document is a product of the Internet Engineering Task Force
   (IETF).  It represents the consensus of the IETF community.  It has
   received public review and has been approved for publication by the
   Internet Engineering Steering Group (IESG).  Further information on
   Internet Standards is available in Section 2 of RFC 5741.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   http://www.rfc-editor.org/info/rfc7277.

Copyright Notice

   Copyright (c) 2014 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
   (http://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.









Bjorklund                    Standards Track                    [Page 1]

RFC 7277                   YANG IP Management                  June 2014


Table of Contents

   1. Introduction ....................................................2
      1.1. Terminology ................................................2
      1.2. Tree Diagrams ..............................................3
   2. IP Data Model ...................................................3
   3. Relationship to the IP-MIB ......................................6
   4. IP Management YANG Module .......................................8
   5. IANA Considerations ............................................24
   6. Security Considerations ........................................24
   7. Acknowledgments ................................................25
   8. References .....................................................25
      8.1. Normative References ......................................25
      8.2. Informative References ....................................26
   Appendix A. Example: NETCONF <get> Reply ..........................28

1.  Introduction

   This document defines a YANG [RFC6020] data model for management of
   IP implementations.

   The data model covers configuration of per-interface IPv4 and IPv6
   parameters, and mappings of IP addresses to link-layer addresses.  It
   also provides information about which IP addresses are operationally
   used, and which link-layer mappings exist.  Per-interface parameters
   are added through augmentation of the interface data model defined in
   [RFC7223].

1.1.  Terminology

   The following terms are defined in [RFC6241] and are not redefined
   here:

   o  client

   o  configuration data

   o  server

   o  state data











Bjorklund                    Standards Track                    [Page 2]

RFC 7277                   YANG IP Management                  June 2014


   The following terms are defined in [RFC6020] and are not redefined
   here:

   o  augment

   o  data model

   o  data node

   The terminology for describing YANG data models is found in
   [RFC6020].

1.2.  Tree Diagrams

   A simplified graphical representation of the data model is used in
   this document.  The meaning of the symbols in these diagrams is as
   follows:

   o  Brackets "[" and "]" enclose list keys.

   o  Abbreviations before data node names: "rw" means configuration
      data (read-write), and "ro" means state data (read-only).

   o  Symbols after data node names: "?" means an optional node, "!"
      means a presence container, and "*" denotes a list and leaf-list.

   o  Parentheses enclose choice and case nodes, and case nodes are also
      marked with a colon (":").

   o  Ellipsis ("...") stands for contents of subtrees that are not
      shown.

2.  IP Data Model

   This document defines the YANG module "ietf-ip", which augments the
   "interface" and "interface-state" lists defined in the
   "ietf-interfaces" module [RFC7223] with IP-specific data nodes, and
   also adds IP-specific state data.













Bjorklund                    Standards Track                    [Page 3]

RFC 7277                   YANG IP Management                  June 2014


   The data model has the following structure for IP configuration per
   interface:

     +--rw if:interfaces
        +--rw if:interface* [name]
           ...
           +--rw ipv4!
           |  +--rw enabled?            boolean
           |  +--rw forwarding?         boolean
           |  +--rw mtu?                uint16
           |  +--rw address* [ip]
           |  |  +--rw ip               inet:ipv4-address-no-zone
           |  |  +--rw (subnet)
           |  |     +--:(prefix-length)
           |  |     |  +--rw ip:prefix-length?   uint8
           |  |     +--:(netmask)
           |  |        +--rw ip:netmask?         yang:dotted-quad
           |  +--rw neighbor* [ip]
           |     +--rw ip                    inet:ipv4-address-no-zone
           |     +--rw link-layer-address    yang:phys-address
           +--rw ipv6!
              +--rw enabled?            boolean
              +--rw forwarding?         boolean
              +--rw mtu?                uint32
              +--rw address* [ip]
              |  +--rw ip               inet:ipv6-address-no-zone
              |  +--rw prefix-length    uint8
              +--rw neighbor* [ip]
              |  +--rw ip                    inet:ipv6-address-no-zone
              |  +--rw link-layer-address    yang:phys-address
              +--rw dup-addr-detect-transmits?   uint32
              +--rw autoconf
                 +--rw create-global-addresses?        boolean
                 +--rw create-temporary-addresses?     boolean
                 +--rw temporary-valid-lifetime?       uint32
                 +--rw temporary-preferred-lifetime?   uint32

   The data model defines two configuration containers per interface --
   "ipv4" and "ipv6", representing the IPv4 and IPv6 address families.
   In each container, there is a leaf "enabled" that controls whether or
   not the address family is enabled on that interface, and a leaf
   "forwarding" that controls whether or not IP packet forwarding for
   the address family is enabled on the interface.  In each container,
   there is also a list of configured addresses, and a list of
   configured mappings from IP addresses to link-layer addresses.






Bjorklund                    Standards Track                    [Page 4]

RFC 7277                   YANG IP Management                  June 2014


   The data model has the following structure for IP state per
   interface:

     +--ro if:interfaces-state
        +--ro if:interface* [name]
           ...
           +--ro ipv4!
           |  +--ro forwarding?   boolean
           |  +--ro mtu?          uint16
           |  +--ro address* [ip]
           |  |  +--ro ip               inet:ipv4-address-no-zone
           |  |  +--ro (subnet)?
           |  |  |  +--:(prefix-length)
           |  |  |  |  +--ro prefix-length?   uint8
           |  |  |  +--:(netmask)
           |  |  |     +--ro netmask?         yang:dotted-quad
           |  |  +--ro origin?          ip-address-origin
           |  +--ro neighbor* [ip]
           |     +--ro ip                    inet:ipv4-address-no-zone
           |     +--ro link-layer-address?   yang:phys-address
           |     +--ro origin?               neighbor-origin
           +--ro ipv6!
              +--ro forwarding?   boolean
              +--ro mtu?          uint32
              +--ro address* [ip]
              |  +--ro ip               inet:ipv6-address-no-zone
              |  +--ro prefix-length    uint8
              |  +--ro origin?          ip-address-origin
              |  +--ro status?          enumeration
              +--ro neighbor* [ip]
                 +--ro ip                    inet:ipv6-address-no-zone
                 +--ro link-layer-address?   yang:phys-address
                 +--ro origin?               neighbor-origin
                 +--ro is-router?            empty
                 +--ro state?                enumeration

   The data model defines two state containers per interface -- "ipv4"
   and "ipv6", representing the IPv4 and IPv6 address families.  In each
   container, there is a leaf "forwarding" that indicates whether or not
   IP packet forwarding is enabled on that interface.  In each
   container, there is also a list of all addresses in use and a list of
   known mappings from IP addresses to link-layer addresses.









Bjorklund                    Standards Track                    [Page 5]

RFC 7277                   YANG IP Management                  June 2014


3.  Relationship to the IP-MIB

   If the device implements the IP-MIB [RFC4293], each entry in the
   "ipv4/address" and "ipv6/address" lists is mapped to one
   ipAddressEntry, where the ipAddressIfIndex refers to the "address"
   entry's interface.

   The IP-MIB defines objects to control IPv6 Router Advertisement
   messages.  The corresponding YANG data nodes are defined in
   [ROUTING-MGMT].

   The entries in "ipv4/neighbor" and "ipv6/neighbor" are mapped to
   ipNetToPhysicalTable.

   The following tables list the YANG data nodes with corresponding
   objects in the IP-MIB.

   +----------------------------------+--------------------------------+
   | YANG data node in                | IP-MIB object                  |
   | /if:interfaces/if:interface      |                                |
   +----------------------------------+--------------------------------+
   | ipv4/enabled                     | ipv4InterfaceEnableStatus      |
   | ipv4/address                     | ipAddressEntry                 |
   | ipv4/address/ip                  | ipAddressAddrType              |
   |                                  | ipAddressAddr                  |
   | ipv4/neighbor                    | ipNetToPhysicalEntry           |
   | ipv4/neighbor/ip                 | ipNetToPhysicalNetAddressType  |
   |                                  | ipNetToPhysicalNetAddress      |
   | ipv4/neighbor/link-layer-address | ipNetToPhysicalPhysAddress     |
   |                                  |                                |
   | ipv6/enabled                     | ipv6InterfaceEnableStatus      |
   | ipv6/forwarding                  | ipv6InterfaceForwarding        |
   | ipv6/address                     | ipAddressEntry                 |
   | ipv6/address/ip                  | ipAddressAddrType              |
   |                                  | ipAddressAddr                  |
   | ipv6/neighbor                    | ipNetToPhysicalEntry           |
   | ipv6/neighbor/link-layer-address | ipNetToPhysicalPhysAddress     |
   | ipv6/neighbor/origin             | ipNetToPhysicalType            |
   +----------------------------------+--------------------------------+

    YANG Interface Configuration Data Nodes and Related IP-MIB Objects










Bjorklund                    Standards Track                    [Page 6]

RFC 7277                   YANG IP Management                  June 2014


   +-----------------------------------+-------------------------------+
   | YANG data node in                 | IP-MIB object                 |
   | /if:interfaces-state/if:interface |                               |
   +-----------------------------------+-------------------------------+
   | ipv4                              | ipv4InterfaceEnableStatus     |
   | ipv4/address                      | ipAddressEntry                |
   | ipv4/address/ip                   | ipAddressAddrType             |
   |                                   | ipAddressAddr                 |
   | ipv4/address/origin               | ipAddressOrigin               |
   | ipv4/neighbor                     | ipNetToPhysicalEntry          |
   | ipv4/neighbor/ip                  | ipNetToPhysicalNetAddressType |
   |                                   | ipNetToPhysicalNetAddress     |
   | ipv4/neighbor/link-layer-address  | ipNetToPhysicalPhysAddress    |
   | ipv4/neighbor/origin              | ipNetToPhysicalType           |
   |                                   |                               |
   | ipv6                              | ipv6InterfaceEnableStatus     |
   | ipv6/forwarding                   | ipv6InterfaceForwarding       |
   | ipv6/address                      | ipAddressEntry                |
   | ipv6/address/ip                   | ipAddressAddrType             |
   |                                   | ipAddressAddr                 |
   | ipv6/address/origin               | ipAddressOrigin               |
   | ipv6/address/status               | ipAddressStatus               |
   | ipv6/neighbor                     | ipNetToPhysicalEntry          |
   | ipv6/neighbor/ip                  | ipNetToPhysicalNetAddressType |
   |                                   | ipNetToPhysicalNetAddress     |
   | ipv6/neighbor/link-layer-address  | ipNetToPhysicalPhysAddress    |
   | ipv6/neighbor/origin              | ipNetToPhysicalType           |
   | ipv6/neighbor/state               | ipNetToPhysicalState          |
   +-----------------------------------+-------------------------------+

        YANG Interface State Data Nodes and Related IP-MIB Objects




















Bjorklund                    Standards Track                    [Page 7]

RFC 7277                   YANG IP Management                  June 2014


4.  IP Management YANG Module

   This module imports typedefs from [RFC6991] and [RFC7223], and it
   references [RFC0791], [RFC0826], [RFC2460], [RFC4861], [RFC4862],
   [RFC4941], and [RFC7217].

   <CODE BEGINS> file "ietf-ip@2014-06-16.yang"

   module ietf-ip {

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

    import ietf-interfaces {
      prefix if;
    }
    import ietf-inet-types {
      prefix inet;
    }
    import ietf-yang-types {
      prefix yang;
    }

    organization
      "IETF NETMOD (NETCONF Data Modeling Language) Working Group";

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

       WG Chair: Thomas Nadeau
                 <mailto:tnadeau@lucidvision.com>

       WG Chair: Juergen Schoenwaelder
                 <mailto:j.schoenwaelder@jacobs-university.de>

       Editor:   Martin Bjorklund
                 <mailto:mbj@tail-f.com>";













Bjorklund                    Standards Track                    [Page 8]

RFC 7277                   YANG IP Management                  June 2014


    description
      "This module contains a collection of YANG definitions for
       configuring IP implementations.

       Copyright (c) 2014 IETF Trust and the persons identified as
       authors of the code.  All rights reserved.

       Redistribution and use in source and binary forms, with or
       without modification, is permitted pursuant to, and subject
       to the license terms contained in, the Simplified BSD License
       set forth in Section 4.c of the IETF Trust's Legal Provisions
       Relating to IETF Documents
       (http://trustee.ietf.org/license-info).

       This version of this YANG module is part of RFC 7277; see
       the RFC itself for full legal notices.";

    revision 2014-06-16 {
      description
        "Initial revision.";
      reference
        "RFC 7277: A YANG Data Model for IP Management";
    }

    /*

     * Features
     */

    feature ipv4-non-contiguous-netmasks {
      description
        "Indicates support for configuring non-contiguous
         subnet masks.";
    }

    feature ipv6-privacy-autoconf {
      description
        "Indicates support for Privacy Extensions for Stateless Address
         Autoconfiguration in IPv6.";
      reference
        "RFC 4941: Privacy Extensions for Stateless Address
                   Autoconfiguration in IPv6";
    }








Bjorklund                    Standards Track                    [Page 9]

RFC 7277                   YANG IP Management                  June 2014


    /*
     * Typedefs
     */

    typedef ip-address-origin {
      type enumeration {
        enum other {
          description
            "None of the following.";
        }
        enum static {
          description
            "Indicates that the address has been statically
             configured - for example, using NETCONF or a Command Line
             Interface.";
        }
        enum dhcp {
          description
            "Indicates an address that has been assigned to this
             system by a DHCP server.";
        }
        enum link-layer {
          description
            "Indicates an address created by IPv6 stateless
             autoconfiguration that embeds a link-layer address in its
             interface identifier.";
        }
        enum random {
          description
            "Indicates an address chosen by the system at

             random, e.g., an IPv4 address within 169.254/16, an
             RFC 4941 temporary address, or an RFC 7217 semantically
             opaque address.";
          reference
            "RFC 4941: Privacy Extensions for Stateless Address
                       Autoconfiguration in IPv6
             RFC 7217: A Method for Generating Semantically Opaque
                       Interface Identifiers with IPv6 Stateless
                       Address Autoconfiguration (SLAAC)";
        }
      }
      description
        "The origin of an address.";
    }






Bjorklund                    Standards Track                   [Page 10]

RFC 7277                   YANG IP Management                  June 2014


    typedef neighbor-origin {
      type enumeration {
        enum other {
          description
            "None of the following.";
        }
        enum static {
          description
            "Indicates that the mapping has been statically
             configured - for example, using NETCONF or a Command Line
             Interface.";
        }
        enum dynamic {
          description
            "Indicates that the mapping has been dynamically resolved
             using, e.g., IPv4 ARP or the IPv6 Neighbor Discovery
             protocol.";
        }
      }
      description
        "The origin of a neighbor entry.";
    }

    /*
     * Configuration data nodes
     */

    augment "/if:interfaces/if:interface" {
      description
        "Parameters for configuring IP on interfaces.

         If an interface is not capable of running IP, the server
         must not allow the client to configure these parameters.";

      container ipv4 {
        presence
          "Enables IPv4 unless the 'enabled' leaf
           (which defaults to 'true') is set to 'false'";
        description
          "Parameters for the IPv4 address family.";











Bjorklund                    Standards Track                   [Page 11]

RFC 7277                   YANG IP Management                  June 2014


        leaf enabled {
          type boolean;
          default true;
          description
            "Controls whether IPv4 is enabled or disabled on this
             interface.  When IPv4 is enabled, this interface is
             connected to an IPv4 stack, and the interface can send
             and receive IPv4 packets.";
        }
        leaf forwarding {
          type boolean;
          default false;
          description
            "Controls IPv4 packet forwarding of datagrams received by,
             but not addressed to, this interface.  IPv4 routers
             forward datagrams.  IPv4 hosts do not (except those
             source-routed via the host).";
        }
        leaf mtu {
          type uint16 {
            range "68..max";
          }
          units octets;
          description
            "The size, in octets, of the largest IPv4 packet that the
             interface will send and receive.

             The server may restrict the allowed values for this leaf,
             depending on the interface's type.

             If this leaf is not configured, the operationally used MTU
             depends on the interface's type.";
          reference
            "RFC 791: Internet Protocol";
        }
        list address {
          key "ip";
          description
            "The list of configured IPv4 addresses on the interface.";

          leaf ip {
            type inet:ipv4-address-no-zone;
            description
              "The IPv4 address on the interface.";
          }






Bjorklund                    Standards Track                   [Page 12]

RFC 7277                   YANG IP Management                  June 2014


          choice subnet {
            mandatory true;
            description
              "The subnet can be specified as a prefix-length, or,
               if the server supports non-contiguous netmasks, as
               a netmask.";
            leaf prefix-length {
              type uint8 {
                range "0..32";
              }
              description
                "The length of the subnet prefix.";
            }
            leaf netmask {
              if-feature ipv4-non-contiguous-netmasks;
              type yang:dotted-quad;
              description
                "The subnet specified as a netmask.";
            }
          }
        }
        list neighbor {
          key "ip";
          description
            "A list of mappings from IPv4 addresses to
             link-layer addresses.

             Entries in this list are used as static entries in the
             ARP Cache.";
          reference
            "RFC 826: An Ethernet Address Resolution Protocol";

          leaf ip {
            type inet:ipv4-address-no-zone;
            description
              "The IPv4 address of the neighbor node.";
          }
          leaf link-layer-address {
            type yang:phys-address;
            mandatory true;
            description
              "The link-layer address of the neighbor node.";
          }
        }

      }





Bjorklund                    Standards Track                   [Page 13]

RFC 7277                   YANG IP Management                  June 2014


      container ipv6 {
        presence
          "Enables IPv6 unless the 'enabled' leaf
           (which defaults to 'true') is set to 'false'";
        description
          "Parameters for the IPv6 address family.";

        leaf enabled {
          type boolean;
          default true;
          description
            "Controls whether IPv6 is enabled or disabled on this
             interface.  When IPv6 is enabled, this interface is
             connected to an IPv6 stack, and the interface can send
             and receive IPv6 packets.";
        }
        leaf forwarding {
          type boolean;
          default false;
          description
            "Controls IPv6 packet forwarding of datagrams received by,
             but not addressed to, this interface.  IPv6 routers
             forward datagrams.  IPv6 hosts do not (except those
             source-routed via the host).";
          reference
            "RFC 4861: Neighbor Discovery for IP version 6 (IPv6)
                       Section 6.2.1, IsRouter";
        }
        leaf mtu {
          type uint32 {
            range "1280..max";
          }
          units octets;
          description
            "The size, in octets, of the largest IPv6 packet that the
             interface will send and receive.

             The server may restrict the allowed values for this leaf,
             depending on the interface's type.

             If this leaf is not configured, the operationally used MTU
             depends on the interface's type.";
          reference
            "RFC 2460: Internet Protocol, Version 6 (IPv6) Specification
                       Section 5";
        }





Bjorklund                    Standards Track                   [Page 14]

RFC 7277                   YANG IP Management                  June 2014


        list address {
          key "ip";
          description
            "The list of configured IPv6 addresses on the interface.";

          leaf ip {
            type inet:ipv6-address-no-zone;
            description
              "The IPv6 address on the interface.";
          }
          leaf prefix-length {
            type uint8 {
              range "0..128";
            }
            mandatory true;
            description
              "The length of the subnet prefix.";
          }
        }
        list neighbor {
          key "ip";
          description
            "A list of mappings from IPv6 addresses to
             link-layer addresses.

             Entries in this list are used as static entries in the
             Neighbor Cache.";
          reference
            "RFC 4861: Neighbor Discovery for IP version 6 (IPv6)";

          leaf ip {
            type inet:ipv6-address-no-zone;
            description
              "The IPv6 address of the neighbor node.";
          }
          leaf link-layer-address {
            type yang:phys-address;
            mandatory true;
            description
              "The link-layer address of the neighbor node.";
          }
        }









Bjorklund                    Standards Track                   [Page 15]

RFC 7277                   YANG IP Management                  June 2014


        leaf dup-addr-detect-transmits {
          type uint32;
          default 1;
          description
            "The number of consecutive Neighbor Solicitation messages
             sent while performing Duplicate Address Detection on a
             tentative address.  A value of zero indicates that
             Duplicate Address Detection is not performed on
             tentative addresses.  A value of one indicates a single
             transmission with no follow-up retransmissions.";
          reference
            "RFC 4862: IPv6 Stateless Address Autoconfiguration";
        }
        container autoconf {
          description
            "Parameters to control the autoconfiguration of IPv6
             addresses, as described in RFC 4862.";
          reference
            "RFC 4862: IPv6 Stateless Address Autoconfiguration";

          leaf create-global-addresses {
            type boolean;
            default true;
            description
              "If enabled, the host creates global addresses as
               described in RFC 4862.";
            reference
              "RFC 4862: IPv6 Stateless Address Autoconfiguration
                         Section 5.5";
          }
          leaf create-temporary-addresses {
            if-feature ipv6-privacy-autoconf;
            type boolean;
            default false;
            description
              "If enabled, the host creates temporary addresses as
               described in RFC 4941.";
            reference
              "RFC 4941: Privacy Extensions for Stateless Address
                         Autoconfiguration in IPv6";
          }










Bjorklund                    Standards Track                   [Page 16]

RFC 7277                   YANG IP Management                  June 2014


          leaf temporary-valid-lifetime {
            if-feature ipv6-privacy-autoconf;
            type uint32;
            units "seconds";
            default 604800;
            description
              "The time period during which the temporary address
               is valid.";
            reference
              "RFC 4941: Privacy Extensions for Stateless Address
                         Autoconfiguration in IPv6
                         - TEMP_VALID_LIFETIME";
          }
          leaf temporary-preferred-lifetime {
            if-feature ipv6-privacy-autoconf;
            type uint32;
            units "seconds";
            default 86400;
            description
              "The time period during which the temporary address is
               preferred.";
            reference
              "RFC 4941: Privacy Extensions for Stateless Address
                         Autoconfiguration in IPv6
                         - TEMP_PREFERRED_LIFETIME";
          }
        }
      }
    }

    /*
     * Operational state data nodes
     */

    augment "/if:interfaces-state/if:interface" {
      description
        "Data nodes for the operational state of IP on interfaces.";

      container ipv4 {
        presence "Present if IPv4 is enabled on this interface";
        config false;
        description
          "Interface-specific parameters for the IPv4 address family.";








Bjorklund                    Standards Track                   [Page 17]

RFC 7277                   YANG IP Management                  June 2014


        leaf forwarding {
          type boolean;
          description
            "Indicates whether IPv4 packet forwarding is enabled or
             disabled on this interface.";
        }
        leaf mtu {
          type uint16 {
            range "68..max";
          }
          units octets;
          description
            "The size, in octets, of the largest IPv4 packet that the
             interface will send and receive.";
          reference
            "RFC 791: Internet Protocol";
        }
        list address {
          key "ip";
          description
            "The list of IPv4 addresses on the interface.";

          leaf ip {
            type inet:ipv4-address-no-zone;
            description
              "The IPv4 address on the interface.";
          }
          choice subnet {
            description
              "The subnet can be specified as a prefix-length, or,
               if the server supports non-contiguous netmasks, as
               a netmask.";
            leaf prefix-length {
              type uint8 {
                range "0..32";
              }
              description
                "The length of the subnet prefix.";
            }
            leaf netmask {
              if-feature ipv4-non-contiguous-netmasks;
              type yang:dotted-quad;
              description
                "The subnet specified as a netmask.";
            }
          }





Bjorklund                    Standards Track                   [Page 18]

RFC 7277                   YANG IP Management                  June 2014


          leaf origin {
            type ip-address-origin;
            description
              "The origin of this address.";
          }
        }
        list neighbor {
          key "ip";
          description
            "A list of mappings from IPv4 addresses to
             link-layer addresses.

             This list represents the ARP Cache.";
          reference
            "RFC 826: An Ethernet Address Resolution Protocol";

          leaf ip {
            type inet:ipv4-address-no-zone;
            description
              "The IPv4 address of the neighbor node.";
          }
          leaf link-layer-address {
            type yang:phys-address;
            description
              "The link-layer address of the neighbor node.";
          }
          leaf origin {
            type neighbor-origin;
            description
              "The origin of this neighbor entry.";
          }
        }

      }

      container ipv6 {
        presence "Present if IPv6 is enabled on this interface";
        config false;
        description
          "Parameters for the IPv6 address family.";











Bjorklund                    Standards Track                   [Page 19]

RFC 7277                   YANG IP Management                  June 2014


        leaf forwarding {
          type boolean;
          default false;
          description
            "Indicates whether IPv6 packet forwarding is enabled or
             disabled on this interface.";
          reference
            "RFC 4861: Neighbor Discovery for IP version 6 (IPv6)
                       Section 6.2.1, IsRouter";
        }
        leaf mtu {
          type uint32 {
            range "1280..max";
          }
          units octets;
          description
            "The size, in octets, of the largest IPv6 packet that the
             interface will send and receive.";
          reference
            "RFC 2460: Internet Protocol, Version 6 (IPv6) Specification
                       Section 5";
        }
        list address {
          key "ip";
          description
            "The list of IPv6 addresses on the interface.";

          leaf ip {
            type inet:ipv6-address-no-zone;
            description
              "The IPv6 address on the interface.";
          }
          leaf prefix-length {
            type uint8 {
              range "0..128";
            }
            mandatory true;
            description
              "The length of the subnet prefix.";
          }
          leaf origin {
            type ip-address-origin;
            description
              "The origin of this address.";
          }






Bjorklund                    Standards Track                   [Page 20]

RFC 7277                   YANG IP Management                  June 2014


          leaf status {
            type enumeration {
              enum preferred {
                description
                  "This is a valid address that can appear as the
                   destination or source address of a packet.";
              }
              enum deprecated {
                description
                  "This is a valid but deprecated address that should
                   no longer be used as a source address in new
                   communications, but packets addressed to such an
                   address are processed as expected.";
              }
              enum invalid {
                description
                  "This isn't a valid address, and it shouldn't appear
                   as the destination or source address of a packet.";
              }
              enum inaccessible {
                description
                  "The address is not accessible because the interface
                   to which this address is assigned is not
                   operational.";
              }
              enum unknown {
                description
                  "The status cannot be determined for some reason.";
              }
              enum tentative {
                description
                  "The uniqueness of the address on the link is being
                   verified.  Addresses in this state should not be
                   used for general communication and should only be
                   used to determine the uniqueness of the address.";
              }
              enum duplicate {
                description
                  "The address has been determined to be non-unique on
                   the link and so must not be used.";
              }










Bjorklund                    Standards Track                   [Page 21]

RFC 7277                   YANG IP Management                  June 2014


              enum optimistic {
                description
                  "The address is available for use, subject to
                   restrictions, while its uniqueness on a link is
                   being verified.";
              }
            }
            description
              "The status of an address.  Most of the states correspond
               to states from the IPv6 Stateless Address
               Autoconfiguration protocol.";
            reference
              "RFC 4293: Management Information Base for the
                         Internet Protocol (IP)
                         - IpAddressStatusTC
               RFC 4862: IPv6 Stateless Address Autoconfiguration";
          }
        }
        list neighbor {
          key "ip";
          description
            "A list of mappings from IPv6 addresses to
             link-layer addresses.

             This list represents the Neighbor Cache.";
          reference
            "RFC 4861: Neighbor Discovery for IP version 6 (IPv6)";

          leaf ip {
            type inet:ipv6-address-no-zone;
            description
              "The IPv6 address of the neighbor node.";
          }
          leaf link-layer-address {
            type yang:phys-address;
            description
              "The link-layer address of the neighbor node.";
          }
          leaf origin {
            type neighbor-origin;
            description
              "The origin of this neighbor entry.";
          }
          leaf is-router {
            type empty;
            description
              "Indicates that the neighbor node acts as a router.";
          }



Bjorklund                    Standards Track                   [Page 22]

RFC 7277                   YANG IP Management                  June 2014


          leaf state {
            type enumeration {
              enum incomplete {
                description
                  "Address resolution is in progress, and the link-layer
                   address of the neighbor has not yet been
                   determined.";
              }
              enum reachable {
                description
                  "Roughly speaking, the neighbor is known to have been
                   reachable recently (within tens of seconds ago).";
              }
              enum stale {
                description
                  "The neighbor is no longer known to be reachable, but
                   until traffic is sent to the neighbor no attempt
                   should be made to verify its reachability.";
              }
              enum delay {
                description
                  "The neighbor is no longer known to be reachable, and
                   traffic has recently been sent to the neighbor.
                   Rather than probe the neighbor immediately, however,
                   delay sending probes for a short while in order to
                   give upper-layer protocols a chance to provide
                   reachability confirmation.";
              }
              enum probe {
                description
                  "The neighbor is no longer known to be reachable, and
                   unicast Neighbor Solicitation probes are being sent
                   to verify reachability.";
              }
            }
            description
              "The Neighbor Unreachability Detection state of this
               entry.";
            reference
              "RFC 4861: Neighbor Discovery for IP version 6 (IPv6)
                         Section 7.3.2";
          }
        }
      }
    }
   }

   <CODE ENDS>



Bjorklund                    Standards Track                   [Page 23]

RFC 7277                   YANG IP Management                  June 2014


5.  IANA Considerations

   This document registers a URI in the "IETF XML Registry" [RFC3688].
   Following the format in RFC 3688, the following registration has been
   made.

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

       Registrant Contact: The NETMOD WG of the IETF.

       XML: N/A; the requested URI is an XML namespace.

   This document registers a YANG module in the "YANG Module Names"
   registry [RFC6020].

    Name:         ietf-ip
    Namespace:    urn:ietf:params:xml:ns:yang:ietf-ip
    Prefix:       ip
    Reference:    RFC 7277

6.  Security Considerations

   The YANG module defined in this memo is designed to be accessed via
   the NETCONF protocol [RFC6241].  The lowest NETCONF layer is the
   secure transport layer and the mandatory-to-implement secure
   transport is SSH [RFC6242].  The NETCONF access control model
   [RFC6536] provides the means to restrict access for particular
   NETCONF users to a pre-configured subset of all available NETCONF
   protocol operations and content.

   There are a number of data nodes defined in the YANG module which 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:

   ipv4/enabled and ipv6/enabled:  These leafs are used to enable or
      disable IPv4 and IPv6 on a specific interface.  By enabling a
      protocol on an interface, an attacker might be able to create an
      unsecured path into a node (or through it if routing is also
      enabled).  By disabling a protocol on an interface, an attacker
      might be able to force packets to be routed through some other
      interface or deny access to some or all of the network via that
      protocol.





Bjorklund                    Standards Track                   [Page 24]

RFC 7277                   YANG IP Management                  June 2014


   ipv4/address and ipv6/address:  These lists specify the configured IP
      addresses on an interface.  By modifying this information, an
      attacker can cause a node to either ignore messages destined to it
      or accept (at least at the IP layer) messages it would otherwise
      ignore.  The use of filtering or security associations may reduce
      the potential damage in the latter case.

   ipv4/forwarding and ipv6/forwarding:  These leafs allow a client to
      enable or disable the forwarding functions on the entity.  By
      disabling the forwarding functions, an attacker would possibly be
      able to deny service to users.  By enabling the forwarding
      functions, an attacker could open a conduit into an area.  This
      might result in the area providing transit for packets it
      shouldn't, or it might allow the attacker access to the area,
      bypassing security safeguards.

   ipv6/autoconf:  The leafs in this branch control the
      autoconfiguration of IPv6 addresses and, in particular, whether or
      not temporary addresses are used.  By modifying the corresponding
      leafs, an attacker might impact the addresses used by a node and
      thus indirectly the privacy of the users using the node.

   ipv4/mtu and ipv6/mtu:  Setting these leafs to very small values can
      be used to slow down interfaces.

7.  Acknowledgments

   The author wishes to thank Jeffrey Lange, Ladislav Lhotka, Juergen
   Schoenwaelder, and Dave Thaler for their helpful comments.

8.  References

8.1.  Normative References

   [RFC0791]  Postel, J., "Internet Protocol", STD 5, RFC 791,
              September 1981.

   [RFC2460]  Deering, S. and R. Hinden, "Internet Protocol, Version 6
              (IPv6) Specification", RFC 2460, December 1998.

   [RFC3688]  Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
              January 2004.

   [RFC4861]  Narten, T., Nordmark, E., Simpson, W., and H. Soliman,
              "Neighbor Discovery for IP version 6 (IPv6)", RFC 4861,
              September 2007.





Bjorklund                    Standards Track                   [Page 25]

RFC 7277                   YANG IP Management                  June 2014


   [RFC4862]  Thomson, S., Narten, T., and T. Jinmei, "IPv6 Stateless
              Address Autoconfiguration", RFC 4862, September 2007.

   [RFC4941]  Narten, T., Draves, R., and S. Krishnan, "Privacy
              Extensions for Stateless Address Autoconfiguration in
              IPv6", RFC 4941, September 2007.

   [RFC6020]  Bjorklund, M., "YANG - A Data Modeling Language for the
              Network Configuration Protocol (NETCONF)", RFC 6020,
              October 2010.

   [RFC6241]  Enns, R., Bjorklund, M., Schoenwaelder, J., and A.
              Bierman, "Network Configuration Protocol (NETCONF)",
              RFC 6241, June 2011.

   [RFC6991]  Schoenwaelder, J., "Common YANG Data Types", RFC 6991,
              July 2013.

   [RFC7223]  Bjorklund, M., "A YANG Data Model for Interface
              Management", RFC 7223, May 2014.

   [XML]      Bray, T., Paoli, J., Sperberg-McQueen, C., Maler, E., and
              F. Yergeau, "Extensible Markup Language (XML) 1.0 (Fifth
              Edition)", W3C Recommendation, November 2008,
              <http://www.w3.org/TR/xml/>.

8.2.  Informative References

   [RFC0826]  Plummer, D., "Ethernet Address Resolution Protocol: Or
              converting network protocol addresses to 48.bit Ethernet
              address for transmission on Ethernet hardware", STD 37,
              RFC 826, November 1982.

   [RFC4293]  Routhier, S., "Management Information Base for the
              Internet Protocol (IP)", RFC 4293, April 2006.

   [RFC6242]  Wasserman, M., "Using the NETCONF Protocol over Secure
              Shell (SSH)", RFC 6242, June 2011.

   [RFC6536]  Bierman, A. and M. Bjorklund, "Network Configuration
              Protocol (NETCONF) Access Control Model", RFC 6536,
              March 2012.









Bjorklund                    Standards Track                   [Page 26]

RFC 7277                   YANG IP Management                  June 2014


   [RFC7217]  Gont, F., "A Method for Generating Semantically Opaque
              Interface Identifiers with IPv6 Stateless Address
              Autoconfiguration (SLAAC)", RFC 7217, April 2014.

   [ROUTING-MGMT]
              Lhotka, L., "A YANG Data Model for Routing Management",
              Work in Progress, May 2014.












































Bjorklund                    Standards Track                   [Page 27]

RFC 7277                   YANG IP Management                  June 2014


Appendix A.  Example: NETCONF <get> Reply

   This section gives an example of a reply to the NETCONF <get> request
   for a device that implements the data model defined in this document.
   The example is written in XML [XML].

   <rpc-reply
      xmlns="urn:ietf:params:xml:ns:netconf:base:1.0"
      message-id="101">
    <data>
      <interfaces
          xmlns="urn:ietf:params:xml:ns:yang:ietf-interfaces"
          xmlns:ianaift="urn:ietf:params:xml:ns:yang:iana-if-type">
        <interface>
          <name>eth0</name>
          <type>ianaift:ethernetCsmacd</type>
          <ipv4 xmlns="urn:ietf:params:xml:ns:yang:ietf-ip">
            <address>
              <ip>192.0.2.1</ip>
              <prefix-length>24</prefix-length>
            </address>
          </ipv4>
          <ipv6 xmlns="urn:ietf:params:xml:ns:yang:ietf-ip">
            <mtu>1280</mtu>
            <address>
              <ip>2001:db8::10</ip>
              <prefix-length>32</prefix-length>
            </address>
            <dup-addr-detect-transmits>0</dup-addr-detect-transmits>
          </ipv6>
        </interface>
      </interfaces>

      <interfaces-state
          xmlns="urn:ietf:params:xml:ns:yang:ietf-interfaces"
          xmlns:ianaift="urn:ietf:params:xml:ns:yang:iana-if-type">
        <interface>
          <name>eth0</name>
          <type>ianaift:ethernetCsmacd</type>
          <!-- other parameters from ietf-interfaces omitted -->











Bjorklund                    Standards Track                   [Page 28]

RFC 7277                   YANG IP Management                  June 2014


          <ipv4 xmlns="urn:ietf:params:xml:ns:yang:ietf-ip">
            <forwarding>false</forwarding>
            <mtu>1500</mtu>
            <address>
              <ip>192.0.2.1</ip>
              <prefix-length>24</prefix-length>
              <origin>static</origin>
            </address>
            <neighbor>
              <ip>192.0.2.2</ip>
              <link-layer-address>00:01:02:03:04:05</link-layer-address>
            </neighbor>
          </ipv4>
          <ipv6 xmlns="urn:ietf:params:xml:ns:yang:ietf-ip">
            <forwarding>false</forwarding>
            <mtu>1500</mtu>
            <address>
              <ip>2001:db8::10</ip>
              <prefix-length>32</prefix-length>
              <origin>static</origin>
              <status>preferred</status>
            </address>
            <address>
              <ip>2001:db8::1:100</ip>
              <prefix-length>32</prefix-length>
              <origin>dhcp</origin>
              <status>preferred</status>
            </address>
            <neighbor>
              <ip>2001:db8::1</ip>
              <link-layer-address>00:01:02:03:04:05</link-layer-address>
              <origin>dynamic</origin>
              <is-router/>
              <state>reachable</state>
            </neighbor>
            <neighbor>
              <ip>2001:db8::4</ip>
              <origin>dynamic</origin>
              <state>incomplete</state>
            </neighbor>
          </ipv6>
        </interface>
      </interfaces-state>
    </data>
   </rpc-reply>






Bjorklund                    Standards Track                   [Page 29]

RFC 7277                   YANG IP Management                  June 2014


Author's Address

   Martin Bjorklund
   Tail-f Systems

   EMail: mbj@tail-f.com













































Bjorklund                    Standards Track                   [Page 30]

