Internet Engineering Task Force (IETF) M. Bjorklund

Internet Engineering Task Force (IETF) M. Bjorklund
Request for Comments: 8344 Tail-f Systems
Obsoletes: 7277 March 2018
Category: Standards Track
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 and system
state.

The YANG data model in this document conforms to the Network
Management Datastore Architecture defined in RFC 8342.

This document obsoletes RFC 7277.

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 7841.

Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
https://www.rfc-editor.org/info/rfc8344.

Copyright Notice

Copyright (c) 2018 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.

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Table of Contents

1. Introduction ....................................................2
1.1. Summary of Changes from RFC 7277 ...........................2
1.2. Terminology ................................................3
1.3. Tree Diagrams ..............................................3
2. IP Data Model ...................................................4
3. Relationship to the IP-MIB ......................................5
4. IP Management YANG Module .......................................7
5. IANA Considerations ............................................27
6. Security Considerations ........................................27
7. References .....................................................29
7.1. Normative References ......................................29
7.2. Informative References ....................................31
Appendix A. Example: NETCONF <get-config> Reply ...................32
Appendix B. Example: NETCONF <get-data> Reply .....................33
Acknowledgments ...................................................34
Author's Address ..................................................34

1. Introduction

This document defines a YANG data model [RFC7950] for management of
IP implementations.

The data model covers configuration of per-interface IPv4 and IPv6
parameters as well as 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 [RFC8343].

This version of the IP data model supports the Network Management
Datastore Architecture (NMDA) [RFC8342].

1.1. Summary of Changes from RFC 7277

The "ipv4" and "ipv6" subtrees with "config false" data nodes in the
"/interfaces-state/interface" subtree are deprecated. All
"config false" data nodes are now present in the "ipv4" and "ipv6"
subtrees in the "/interfaces/interface" subtree.

Servers that do not implement NMDA or that wish to support clients
that do not implement NMDA MAY implement the deprecated "ipv4" and
"ipv6" subtrees in the "/interfaces-state/interface" subtree.

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1.2. Terminology

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in
BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.

The following terms are defined in [RFC8342] and are not redefined
here:

o client

o server

o configuration

o system state

o intended configuration

o running configuration datastore

o operational state

o operational state datastore

The following terms are defined in [RFC7950] and are not redefined
here:

o augment

o data model

o data node

The terminology for describing YANG data models is found in
[RFC7950].

1.3. Tree Diagrams

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

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2. IP Data Model

This document defines the YANG module "ietf-ip", which augments the
"interface" lists defined in the "ietf-interfaces" module [RFC8343]
with IP-specific data nodes.

The data model has the following structure for IP data nodes per
interface, excluding the deprecated data nodes:

module: ietf-ip
augment /if:interfaces/if:interface:
+--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 prefix-length? uint8
| | | +--:(netmask)
| | | +--rw netmask? yang:dotted-quad
| | | {ipv4-non-contiguous-netmasks}?
| | +--ro origin? ip-address-origin
| +--rw neighbor* [ip]
| +--rw ip inet:ipv4-address-no-zone
| +--rw link-layer-address yang:phys-address
| +--ro origin? neighbor-origin
+--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
| +--ro origin? ip-address-origin
| +--ro status? enumeration
+--rw neighbor* [ip]
| +--rw ip inet:ipv6-address-no-zone
| +--rw link-layer-address yang:phys-address
| +--ro origin? neighbor-origin
| +--ro is-router? empty
| +--ro state? enumeration
+--rw dup-addr-detect-transmits? uint32

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+--rw autoconf
+--rw create-global-addresses? boolean
+--rw create-temporary-addresses? boolean
| {ipv6-privacy-autoconf}?
+--rw temporary-valid-lifetime? uint32
| {ipv6-privacy-autoconf}?
+--rw temporary-preferred-lifetime? uint32
{ipv6-privacy-autoconf}?

The data model defines two 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 addresses and a list of mappings from IP addresses to
link-layer addresses.

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
[RFC8022].

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

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The following table lists the YANG data nodes with corresponding
objects in the IP-MIB.

+----------------------------------+--------------------------------+
| YANG data node in | IP-MIB object |
| /if:interfaces/if:interface | |
+----------------------------------+--------------------------------+
| ipv4 | ipv4InterfaceEnableStatus |
| 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 |
| ipv4/neighbor/origin | ipNetToPhysicalType |
| ipv6 | ipv6InterfaceEnableStatus |
| ipv6/enabled | ipv6InterfaceEnableStatus |
| ipv6/forwarding | ipv6InterfaceForwarding |
| ipv6/address | ipAddressEntry |
| ipv6/address/ip | ipAddressAddrType |
| | ipAddressAddr |
| ipv4/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 Data Nodes and Related IP-MIB Objects

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4. IP Management YANG Module

This module imports typedefs from [RFC6991] and [RFC8343], and it
references [RFC791], [RFC826], [RFC4861], [RFC4862], [RFC4941],
[RFC7217], and [RFC8200].

<CODE BEGINS> file "[email protected]"
module ietf-ip {
yang-version 1.1;
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 (Network Modeling) Working Group";

contact
"WG Web: <https://datatracker.ietf.org/wg/netmod/>
WG List: <mailto:[email protected]>

Editor: Martin Bjorklund
<mailto:[email protected]>";
description
"This module contains a collection of YANG definitions for
managing IP implementations.

Copyright (c) 2018 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 8344; see
the RFC itself for full legal notices.";

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revision 2018-02-22 {
description
"Updated to support NMDA.";
reference
"RFC 8344: A YANG Data Model for IP Management";
}

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";
}

/*
* Typedefs
*/

typedef ip-address-origin {
type enumeration {
enum other {
description
"None of the following.";
}

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enum static {
description
"Indicates that the address has been statically
configured -- for example, using the Network Configuration
Protocol (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, a
temporary address as described in RFC 4941, or a
semantically opaque address as described in RFC 7217.";
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.";
}

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.";
}

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enum dynamic {
description
"Indicates that the mapping has been dynamically resolved
using, for example, IPv4 ARP or the IPv6 Neighbor
Discovery protocol.";
}
}
description
"The origin of a neighbor entry.";
}

/*
* Data nodes
*/

augment "/if:interfaces/if:interface" {
description
"IP parameters 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.";

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).";
}

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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 IPv4 addresses on the interface.";

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

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

Entries in this list in the intended configuration are
used as static entries in the ARP Cache.

In the operational state, 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;
mandatory true;
description
"The link-layer address of the neighbor node.";
}
leaf origin {
type neighbor-origin;
config false;
description
"The origin of this neighbor entry.";
}
}
}

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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 8200: Internet Protocol, Version 6 (IPv6)
Specification
Section 5";
}

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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;
config false;
description
"The origin of this address.";
}
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.";
}

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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.";
}
enum optimistic {
description
"The address is available for use, subject to
restrictions, while its uniqueness on a link is
being verified.";
}
}
config false;
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";
}
}

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list neighbor {
key "ip";
description
"A list of mappings from IPv6 addresses to
link-layer addresses.

Entries in this list in the intended configuration are
used as static entries in the Neighbor Cache.

In the operational state, 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;
mandatory true;
description
"The link-layer address of the neighbor node.

In the operational state, if the neighbor's 'state' leaf
is 'incomplete', this leaf is not instantiated.";
}
leaf origin {
type neighbor-origin;
config false;
description
"The origin of this neighbor entry.";
}
leaf is-router {
type empty;
config false;
description
"Indicates that the neighbor node acts as a router.";
}

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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.";
}
}
config false;
description
"The Neighbor Unreachability Detection state of this
entry.";
reference
"RFC 4861: Neighbor Discovery for IP version 6 (IPv6)
Section 7.3.2";
}
}

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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";
}

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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";
}
}
}
}

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/*
* Legacy operational state data nodes
*/

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

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

leaf forwarding {
type boolean;
status deprecated;
description
"Indicates whether IPv4 packet forwarding is enabled or
disabled on this interface.";
}
leaf mtu {
type uint16 {
range "68..max";
}
units "octets";
status deprecated;
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";
status deprecated;
description
"The list of IPv4 addresses on the interface.";

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

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choice subnet {
status deprecated;
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";
}
status deprecated;
description
"The length of the subnet prefix.";
}
leaf netmask {
if-feature ipv4-non-contiguous-netmasks;
type yang:dotted-quad;
status deprecated;
description
"The subnet specified as a netmask.";
}
}
leaf origin {
type ip-address-origin;
status deprecated;
description
"The origin of this address.";
}
}
list neighbor {
key "ip";
status deprecated;
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;
status deprecated;
description
"The IPv4 address of the neighbor node.";
}

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leaf link-layer-address {
type yang:phys-address;
status deprecated;
description
"The link-layer address of the neighbor node.";
}
leaf origin {
type neighbor-origin;
status deprecated;
description
"The origin of this neighbor entry.";
}
}
}

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

leaf forwarding {
type boolean;
default false;
status deprecated;
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";
status deprecated;
description
"The size, in octets, of the largest IPv6 packet that the
interface will send and receive.";
reference
"RFC 8200: Internet Protocol, Version 6 (IPv6)
Specification
Section 5";
}

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

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

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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.";
}
enum optimistic {
description
"The address is available for use, subject to
restrictions, while its uniqueness on a link is
being verified.";
}
}
status deprecated;
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";
}
}

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list neighbor {
key "ip";
status deprecated;
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;
status deprecated;
description
"The IPv6 address of the neighbor node.";
}
leaf link-layer-address {
type yang:phys-address;
status deprecated;
description
"The link-layer address of the neighbor node.";
}
leaf origin {
type neighbor-origin;
status deprecated;
description
"The origin of this neighbor entry.";
}
leaf is-router {
type empty;
status deprecated;
description
"Indicates that the neighbor node acts as a router.";
}
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).";
}

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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.";
}
}
status deprecated;
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>

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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 8344

6. 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
[RFC5246].

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:

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

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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.

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.

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7. References

7.1. Normative References

[RFC791] Postel, J., "Internet Protocol", STD 5, RFC 791,
DOI 10.17487/RFC0791, September 1981,
<https://www.rfc-editor.org/info/rfc791>.

[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.

[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
DOI 10.17487/RFC3688, January 2004,
<https://www.rfc-editor.org/info/rfc3688>.

[RFC4861] Narten, T., Nordmark, E., Simpson, W., and H. Soliman,
"Neighbor Discovery for IP version 6 (IPv6)", RFC 4861,
DOI 10.17487/RFC4861, September 2007,
<https://www.rfc-editor.org/info/rfc4861>.

[RFC4862] Thomson, S., Narten, T., and T. Jinmei, "IPv6 Stateless
Address Autoconfiguration", RFC 4862,
DOI 10.17487/RFC4862, September 2007,
<https://www.rfc-editor.org/info/rfc4862>.

[RFC4941] Narten, T., Draves, R., and S. Krishnan, "Privacy
Extensions for Stateless Address Autoconfiguration in
IPv6", RFC 4941, DOI 10.17487/RFC4941, September 2007,
<https://www.rfc-editor.org/info/rfc4941>.

[RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security
(TLS) Protocol Version 1.2", RFC 5246,
DOI 10.17487/RFC5246, August 2008,
<https://www.rfc-editor.org/info/rfc5246>.

[RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for
the Network Configuration Protocol (NETCONF)", RFC 6020,
DOI 10.17487/RFC6020, October 2010,
<https://www.rfc-editor.org/info/rfc6020>.

[RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
and A. Bierman, Ed., "Network Configuration Protocol
(NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
<https://www.rfc-editor.org/info/rfc6241>.

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RFC 8344 YANG IP Management March 2018

[RFC6242] Wasserman, M., "Using the NETCONF Protocol over Secure
Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011,
<https://www.rfc-editor.org/info/rfc6242>.

[RFC6991] Schoenwaelder, J., Ed., "Common YANG Data Types",
RFC 6991, DOI 10.17487/RFC6991, July 2013,
<https://www.rfc-editor.org/info/rfc6991>.

[RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
RFC 7950, DOI 10.17487/RFC7950, August 2016,
<https://www.rfc-editor.org/info/rfc7950>.

[RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
<https://www.rfc-editor.org/info/rfc8040>.

[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in
RFC 2119 Key Words", BCP 14, RFC 8174,
DOI 10.17487/RFC8174, May 2017,
<https://www.rfc-editor.org/info/rfc8174>.

[RFC8200] Deering, S. and R. Hinden, "Internet Protocol, Version 6
(IPv6) Specification", STD 86, RFC 8200,
DOI 10.17487/RFC8200, July 2017,
<https://www.rfc-editor.org/info/rfc8200>.

[RFC8341] Bierman, A. and M. Bjorklund, "Network Configuration
Access Control Model", STD 91, RFC 8341,
DOI 10.17487/RFC8341, March 2018,
<https://www.rfc-editor.org/info/rfc8341>.

[RFC8342] Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K.,
and R. Wilton, "Network Management Datastore Architecture
(NMDA)", RFC 8342, DOI 10.17487/RFC8342, March 2018,
<https://www.rfc-editor.org/info/rfc8342>.

[RFC8343] Bjorklund, M., "A YANG Data Model for Interface
Management", RFC 8343, DOI 10.17487/RFC8343, March 2018,
<https://www.rfc-editor.org/info/rfc8343>.

[W3C.REC-xml-20081126]
Bray, T., Paoli, J., Sperberg-McQueen, M., Maler, E., and
F. Yergeau, "Extensible Markup Language (XML) 1.0
(Fifth Edition)", World Wide Web Consortium Recommendation
REC-xml-20081126, November 2008,
<https://www.w3.org/TR/2008/REC-xml-20081126>.

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7.2. Informative References

[RFC826] Plummer, D., "An Ethernet Address Resolution Protocol: Or
Converting Network Protocol Addresses to 48.bit Ethernet
Address for Transmission on Ethernet Hardware", STD 37,
RFC 826, DOI 10.17487/RFC0826, November 1982,
<https://www.rfc-editor.org/info/rfc826>.

[RFC4293] Routhier, S., Ed., "Management Information Base for the
Internet Protocol (IP)", RFC 4293, DOI 10.17487/RFC4293,
April 2006, <https://www.rfc-editor.org/info/rfc4293>.

[RFC7217] Gont, F., "A Method for Generating Semantically Opaque
Interface Identifiers with IPv6 Stateless Address
Autoconfiguration (SLAAC)", RFC 7217,
DOI 10.17487/RFC7217, April 2014,
<https://www.rfc-editor.org/info/rfc7217>.

[RFC8022] Lhotka, L. and A. Lindem, "A YANG Data Model for Routing
Management", RFC 8022, DOI 10.17487/RFC8022,
November 2016, <https://www.rfc-editor.org/info/rfc8022>.

[RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams",
BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018,
<https://www.rfc-editor.org/info/rfc8340>.

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Appendix A. Example: NETCONF <get-config> Reply

This section gives an example of a reply to the NETCONF <get-config>
request for the running configuration datastore for a device that
implements the data model defined in this document.

The XML [W3C.REC-xml-20081126] snippets that follow in this section
and in Appendix B are provided as examples only.

<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>
</data>
</rpc-reply>

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Appendix B. Example: NETCONF <get-data> Reply

This section gives an example of a reply to the NETCONF <get-data>
request for the operational state datastore for a device that
implements the data model defined in this document.

This example uses the "origin" annotation, which is defined in the
module "ietf-origin" [RFC8342].

<rpc-reply
xmlns="urn:ietf:params:xml:ns:netconf:base:1.0"
message-id="101">
<data xmlns="urn:ietf:params:xml:ns:yang:ietf-netconf-datastores">
<interfaces
xmlns="urn:ietf:params:xml:ns:yang:ietf-interfaces"
xmlns:ianaift="urn:ietf:params:xml:ns:yang:iana-if-type"
xmlns:or="urn:ietf:params:xml:ns:yang:ietf-origin">

<interface or:origin="or:intended">
<name>eth0</name>
<type>ianaift:ethernetCsmacd</type>


<ipv4 xmlns="urn:ietf:params:xml:ns:yang:ietf-ip">
<enabled or:origin="or:default">true</enabled>
<forwarding or:origin="or:default">false</forwarding>
<mtu or:origin="or:system">1500</mtu>
<address>
<ip>192.0.2.1</ip>
<prefix-length>24</prefix-length>
<origin>static</origin>
</address>
<neighbor or:origin="or:learned">
<ip>192.0.2.2</ip>
<link-layer-address>
00:00:5E:00:53:AB
</link-layer-address>
</neighbor>
</ipv4>
<ipv6 xmlns="urn:ietf:params:xml:ns:yang:ietf-ip">
<enabled or:origin="or:default">true</enabled>
<forwarding or:origin="or:default">false</forwarding>
<mtu>1280</mtu>

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<address>
<ip>2001:db8::10</ip>
<prefix-length>32</prefix-length>
<origin>static</origin>
<status>preferred</status>
</address>
<address or:origin="or:learned">
<ip>2001:db8::1:100</ip>
<prefix-length>32</prefix-length>
<origin>dhcp</origin>
<status>preferred</status>
</address>
<dup-addr-detect-transmits>0</dup-addr-detect-transmits>
<neighbor or:origin="or:learned">
<ip>2001:db8::1</ip>
<link-layer-address>
00:00:5E:00:53:AB
</link-layer-address>
<origin>dynamic</origin>
<is-router/>
<state>reachable</state>
</neighbor>
<neighbor or:origin="or:learned">
<ip>2001:db8::4</ip>
<origin>dynamic</origin>
<state>incomplete</state>
</neighbor>
</ipv6>
</interface>
</interfaces>
</data>
</rpc-reply>

Acknowledgments

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

Author's Address

Martin Bjorklund
Tail-f Systems

Email: [email protected]

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