RFC7277
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.
Contents
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.
Terminology
The following terms are defined in RFC6241 and are not redefined here:
o client
o configuration data
o server
o state data
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.
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.
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.
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.
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.
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
+-----------------------------------+-------------------------------+ | 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
IP Management YANG Module
This module imports typedefs from RFC6991 and RFC7223, and it references RFC0791, RFC0826, RFC2460, RFC4861, RFC4862, RFC4941, and RFC7217.
file "[email protected]"
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:[email protected]>
WG Chair: Thomas Nadeau
<mailto:[email protected]>
WG Chair: Juergen Schoenwaelder
<mailto:[email protected]>
Editor: Martin Bjorklund
<mailto:[email protected]>";
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";
}
/*
* 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.";
}
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.";
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.";
}
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.";
}
}
}
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";
}
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.";
}
}
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";
}
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.";
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.";
}
}
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.";
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.";
}
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.";
}
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.";
}
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";
}
}
}
}
}
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
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.
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.
Acknowledgments
The author wishes to thank Jeffrey Lange, Ladislav Lhotka, Juergen
Schoenwaelder, and Dave Thaler for their helpful comments.
References
Normative References
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.
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/>.
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.
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.
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">
<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>
<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>
</rpc-reply>
Author's Address
Martin Bjorklund
Tail-f Systems
EMail: [email protected]
