DHC Working Group I. Farrer, Ed.
Internet-Draft Deutsche Telekom AG
Intended status: Standards Track 18 November 2021
Expires: 22 May 2022
YANG Data Model for DHCPv6 Configuration
draft-ietf-dhc-dhcpv6-yang-24
Abstract
This document describes YANG data modules for the configuration and
management of DHCPv6 (Dynamic Host Configuration Protocol for IPv6
RFC8415) servers, relays, and clients.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on 22 May 2022.
Copyright Notice
Copyright (c) 2021 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.
Farrer Expires 22 May 2022 [Page 1]
Internet-Draft DHCPv6 YANG Model November 2021
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Scope . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.2. Extensibility of the DHCPv6 Server YANG Module . . . . . 3
1.2.1. DHCPv6 Option Definitions . . . . . . . . . . . . . . 4
1.3. Terminology . . . . . . . . . . . . . . . . . . . . . . . 6
2. Requirements Language . . . . . . . . . . . . . . . . . . . . 6
3. DHCPv6 Tree Diagrams . . . . . . . . . . . . . . . . . . . . 6
3.1. DHCPv6 Server Tree Diagram . . . . . . . . . . . . . . . 6
3.2. DHCPv6 Relay Tree Diagram . . . . . . . . . . . . . . . . 13
3.3. DHCPv6 Client Tree Diagram . . . . . . . . . . . . . . . 15
4. DHCPv6 YANG Modules . . . . . . . . . . . . . . . . . . . . . 20
4.1. DHCPv6 Common YANG Module . . . . . . . . . . . . . . . . 20
4.2. DHCPv6 Server YANG Module . . . . . . . . . . . . . . . . 28
4.3. DHCPv6 Relay YANG Module . . . . . . . . . . . . . . . . 48
4.4. DHCPv6 Client YANG Module . . . . . . . . . . . . . . . . 58
5. Security Considerations . . . . . . . . . . . . . . . . . . . 73
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 74
7. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 75
8. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 75
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 76
9.1. Normative References . . . . . . . . . . . . . . . . . . 76
9.2. Informative References . . . . . . . . . . . . . . . . . 78
Appendix A. Data Tree Examples . . . . . . . . . . . . . . . . . 78
A.1. DHCPv6 Server Configuration Examples . . . . . . . . . . 79
A.2. DHCPv6 Relay Configuration Example . . . . . . . . . . . 83
A.3. DHCPv6 Client Configuration Example . . . . . . . . . . . 84
Appendix B. Example of Augmenting Additional DHCPv6 Option
Definitions . . . . . . . . . . . . . . . . . . . . . . . 87
Appendix C. Example Vendor Specific Server Configuration
Module . . . . . . . . . . . . . . . . . . . . . . . . . 90
Appendix D. Example definition of class-selector
configuration . . . . . . . . . . . . . . . . . . . . . . 97
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 104
1. Introduction
DHCPv6 [RFC8415] is used for supplying configuration and other
relevant parameters to clients in IPv6 networks. This document
defines YANG [RFC7950] modules for the configuration and management
of DHCPv6 'element' (servers, relays, and clients) using the Network
Configuration Protocol (NETCONF [RFC6241]) or RESTCONF [RFC8040]
protocols.
Farrer Expires 22 May 2022 [Page 2]
Internet-Draft DHCPv6 YANG Model November 2021
Separate modules are defined for each element. Additionally, a
'common' module contains typedefs and groupings used by all of the
element modules. Appendix A provides XML examples for each of the
element modules and shows their interaction.
The relay and client modules provide configuration which is
applicable to devices' interfaces. This is done by importing the
ietf-interfaces module [RFC8343] and using interface-refs to the
relevant interface(s).
It is worth noting that as DHCPv6 is itself a client configuration
protocol, it is not the intention of this document to provide a
replacement for the allocation of DHCPv6 assigned addressing and
parameters by using NETCONF/YANG. The DHCPv6 client module is
intended for the configuration and monitoring of the DHCPv6 client
function and does not replace DHCPv6 address and parameter
configuration.
The YANG modules in this document adopt the Network Management
Datastore Architecture (NMDA) [RFC8342].
1.1. Scope
[RFC8415] describes the current version of the DHCPv6 base protocol
specification. A large number of additional specifications have also
been published, extending DHCPv6 element functionality and adding new
options. The YANG modules contained in this document do not attempt
to capture all of these extensions and additions, rather to model the
DHCPv6 functions and options covered in [RFC8415]. A focus has also
been given on the extensibility of the modules so that they are easy
to augment to add additional functionality as required by a
particular implementation or deployment scenario.
1.2. Extensibility of the DHCPv6 Server YANG Module
The modules in this document only attempt to model DHCPv6-specific
behavior and do not cover the configuration and management of
functionality relevant for specific server implementations. The
level of variance between implementations is too great to attempt to
standardize them in a way that is useful without being restrictive.
However, it is recognized that implementation-specific configuration
and management is also an essential part of DHCP deployment and
operations. To resolve this, Appendix C contains an example YANG
module for the configuration of implementation-specific functions,
illustrating how this functionality can be augmented into the main
'ietf-dhcpv6-server.yang' module.
Farrer Expires 22 May 2022 [Page 3]
Internet-Draft DHCPv6 YANG Model November 2021
In DHCPv6, the concept of 'class selection' for messages received by
the server is common. This is the identification and classification
of messages based on a number of parameters so that the correct
provisioning information can be supplied. For example, allocating a
prefix from the correct pool, or supplying a set of options relevant
for a specific vendor's client implementation. During the
development of this document, implementations were researched and the
findings were that while this function is common to all, the method
for configuring and implementing this function differs greatly.
Therefore, configuration of the class selection function has been
omitted from the DHCPv6 server module to allow implementors to define
their own suitable YANG modules. Appendix D provides an example of
this, to demonstrate how this is can be integrated with the main
'ietf-dhcpv6-server.yang' module.
1.2.1. DHCPv6 Option Definitions
A large number of DHCPv6 options have been created in addition to
those defined in [RFC8415]. As implementations differ widely as to
which DHCPv6 options they support, the following approach has been
taken to defining options: Only the DHCPv6 options defined in
[RFC8415] are included in this document.
Of these, only the options that require operator configuration are
modelled. For example, OPTION_IA_NA (3) is created by the DHCP
server when requested by the client. The contents of the fields in
the option are based on a number of input configuration parameters
which the server will apply when it receives the request (e.g., the
T1/T2 timers that are relevant for the pool of addresses). As a
result, there are no fields that are directly configurable for the
option, so it is not modelled.
The following table shows the DHCPv6 options that are modeled, the
element(s) they are sent by, and the relevant YANG module name:
+---------------------+------+-----+------+-------------------------+
| Name |Server|Relay|Client| Module Name |
+=====================+======+=====+======+=========================+
|OPTION_ORO (6) Option| | | X | ietf-dhcpv6-client.yang |
| Request Option | | | | |
+---------------------+------+-----+------+-------------------------+
|OPTION_PREFERENCE (7)| X | | | ietf-dhcpv6-server.yang |
| Preference Option | | | | |
+---------------------+------+-----+------+-------------------------+
| OPTION_AUTH (11) | X | X | | ietf-dhcpv6-common.yang |
|Authentication Option| | | | |
+---------------------+------+-----+------+-------------------------+
| OPTION_UNICAST (12) | X | | | ietf-dhcpv6-server.yang |
Farrer Expires 22 May 2022 [Page 4]
Internet-Draft DHCPv6 YANG Model November 2021
|Server Unicast Option| | | | |
+---------------------+------+-----+------+-------------------------+
| OPTION_RAPID_COMMIT | X | | X | ietf-dhcpv6-common.yang |
| (14) Rapid Commit | | | | |
| Option | | | | |
+---------------------+------+-----+------+-------------------------+
| OPTION_USER_CLASS | | | X | ietf-dhcpv6-client.yang |
| (15) User Class | | | | |
| Option | | | | |
+---------------------+------+-----+------+-------------------------+
| OPTION_VENDOR_CLASS | | | X | ietf-dhcpv6-client.yang |
| (16) Vendor Class | | | | |
| Option | | | | |
+---------------------+------+-----+------+-------------------------+
| OPTION_VENDOR_OPTS | X | | X | ietf-dhcpv6-common.yang |
|(17) Vendor-specific | | | | |
| Information Option | | | | |
+---------------------+------+-----+------+-------------------------+
| OPTION_INTERFACE_ID | | X | | ietf-dhcpv6-relay.yang |
| (18) Interface-Id | | | | |
| Option | | | | |
+---------------------+------+-----+------+-------------------------+
| OPTION_RECONF_MSG | X | | | ietf-dhcpv6-server.yang |
| (19) Reconfigure | | | | |
| Message Option | | | | |
+---------------------+------+-----+------+-------------------------+
|OPTION_RECONF_ACCEPT | X | | X | ietf-dhcpv6-client.yang |
| (20) Reconfigure | | | | |
| Accept Option | | | | |
+---------------------+------+-----+------+-------------------------+
| OPTION_INFORMATION | X | | | ietf-dhcpv6-server.yang |
| _REFRESH_TIME (32) | | | | |
| Information Refresh | | | | |
| Time Option | | | | |
+---------------------+------+-----+------+-------------------------+
| OPTION_SOL_MAX_RT | X | | | ietf-dhcpv6-server.yang |
| (82) sol max rt | | | | |
| Option | | | | |
+---------------------+------+-----+------+-------------------------+
| OPTION_INF_MAX_RT | X | | | ietf-dhcpv6-server.yang |
| (83) inf max rt | | | | |
| Option | | | | |
+---------------------+------+-----+------+-------------------------+
Table 1: Modeled DHCPv6 Options
Farrer Expires 22 May 2022 [Page 5]
Internet-Draft DHCPv6 YANG Model November 2021
Further options definitions can be added using additional YANG
modules via augmentation of the relevant element modules from this
document. Appendix B contains an example module showing how the
DHCPv6 option definitions can be extended in this manner. Some
guidance on how to write YANG modules for additional DHCPv6 options
is also provided.
1.3. Terminology
The reader should be familiar with the YANG data modeling language
defined in [RFC7950].
The YANG modules in this document adopt the Network Management
Datastore Architecture (NMDA) [RFC8342]. The meanings of the symbols
used in tree diagrams are defined in [RFC8340].
The reader should be familiar with DHCPv6 relevant terminology as
defined in [RFC8415] and other relevant documents.
2. Requirements Language
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.
3. DHCPv6 Tree Diagrams
3.1. DHCPv6 Server Tree Diagram
The tree diagram in Figure 1 provides an overview of the DHCPv6
server module. The tree also includes the common functions module
Section 4.1.
module: ietf-dhcpv6-server
+--rw dhcpv6-server
+--rw enabled? boolean
+--rw server-duid? dhc6:duid
+--rw vendor-config
+--rw option-sets
| +--rw option-set* [option-set-id]
| +--rw option-set-id uint32
| +--rw description? string
| +--rw preference-option
| | +--rw pref-value? uint8
| +--rw auth-option
| | +--rw protocol? uint8
Farrer Expires 22 May 2022 [Page 6]
Internet-Draft DHCPv6 YANG Model November 2021
| | +--rw algorithm? uint8
| | +--rw rdm? uint8
| | +--rw replay-detection? uint64
| | +--rw auth-information? string
| +--rw server-unicast-option
| | +--rw server-address? inet:ipv6-address
| +--rw rapid-commit-option!
| +--rw vendor-specific-information-options
| | +--rw vendor-specific-information-option*
| | [enterprise-number]
| | +--rw enterprise-number uint32
| | +--rw vendor-option-data* [sub-option-code]
| | +--rw sub-option-code uint16
| | +--rw sub-option-data? string
| +--rw reconfigure-message-option
| | +--rw msg-type? uint8
| +--rw reconfigure-accept-option!
| +--rw info-refresh-time-option
| | +--rw info-refresh-time? dhc6:timer-seconds32
| +--rw sol-max-rt-option
| | +--rw sol-max-rt-value? dhc6:timer-seconds32
| +--rw inf-max-rt-option
| +--rw inf-max-rt-value? dhc6:timer-seconds32
+--rw class-selector
+--rw allocation-ranges
+--rw option-set-id* leafref
+--rw valid-lifetime? dhc6:timer-seconds32
+--rw renew-time? dhc6:timer-seconds32
+--rw rebind-time? dhc6:timer-seconds32
+--rw preferred-lifetime? dhc6:timer-seconds32
+--rw rapid-commit? boolean
+--rw allocation-range* [id]
| +--rw id uint32
| +--rw description? string
| +--rw network-prefix inet:ipv6-prefix
| +--rw option-set-id* leafref
| +--rw valid-lifetime? dhc6:timer-seconds32
| +--rw renew-time? dhc6:timer-seconds32
| +--rw rebind-time? dhc6:timer-seconds32
| +--rw preferred-lifetime? dhc6:timer-seconds32
| +--rw rapid-commit? boolean
| +--rw address-pools {na-assignment}?
| | +--rw address-pool* [pool-id]
| | +--rw pool-id string
| | +--rw pool-prefix
| | | inet:ipv6-prefix
| | +--rw start-address
| | | inet:ipv6-address-no-zone
Farrer Expires 22 May 2022 [Page 7]
Internet-Draft DHCPv6 YANG Model November 2021
| | +--rw end-address
| | | inet:ipv6-address-no-zone
| | +--rw max-address-utilization? dhc6:threshold
| | +--rw option-set-id* leafref
| | +--rw valid-lifetime?
| | | dhc6:timer-seconds32
| | +--rw renew-time?
| | | dhc6:timer-seconds32
| | +--rw rebind-time?
| | | dhc6:timer-seconds32
| | +--rw preferred-lifetime?
| | | dhc6:timer-seconds32
| | +--rw rapid-commit? boolean
| | +--rw host-reservations
| | | +--rw host-reservation* [reserved-addr]
| | | +--rw client-duid? dhc6:duid
| | | +--rw reserved-addr
| | | | inet:ipv6-address
| | | +--rw option-set-id* leafref
| | | +--rw valid-lifetime?
| | | | dhc6:timer-seconds32
| | | +--rw renew-time?
| | | | dhc6:timer-seconds32
| | | +--rw rebind-time?
| | | | dhc6:timer-seconds32
| | | +--rw preferred-lifetime?
| | | | dhc6:timer-seconds32
| | | +--rw rapid-commit? boolean
| | +--ro active-leases
| | +--ro total-count uint64
| | +--ro allocated-count uint64
| | +--ro active-lease* [leased-address]
| | +--ro leased-address
| | | inet:ipv6-address
| | +--ro client-duid? dhc6:duid
| | +--ro ia-id uint32
| | +--ro allocation-time?
| | | yang:date-and-time
| | +--ro last-renew-rebind?
| | | yang:date-and-time
| | +--ro preferred-lifetime?
| | | dhc6:timer-seconds32
| | +--ro valid-lifetime?
| | | dhc6:timer-seconds32
| | +--ro lease-t1?
| | | dhc6:timer-seconds32
| | +--ro lease-t2?
| | | dhc6:timer-seconds32
Farrer Expires 22 May 2022 [Page 8]
Internet-Draft DHCPv6 YANG Model November 2021
| | +--ro status
| | +--ro code? uint16
| | +--ro message? string
| +--rw prefix-pools {prefix-delegation}?
| +--rw prefix-pool* [pool-id]
| +--rw pool-id string
| +--rw pool-prefix
| | inet:ipv6-prefix
| +--rw client-prefix-length uint8
| +--rw max-pd-space-utilization? dhc6:threshold
| +--rw option-set-id* leafref
| +--rw valid-lifetime?
| | dhc6:timer-seconds32
| +--rw renew-time?
| | dhc6:timer-seconds32
| +--rw rebind-time?
| | dhc6:timer-seconds32
| +--rw preferred-lifetime?
| | dhc6:timer-seconds32
| +--rw rapid-commit? boolean
| +--rw host-reservations
| | +--rw prefix-reservation* [reserved-prefix]
| | | +--rw client-duid? dhc6:duid
| | | +--rw reserved-prefix
| | | | inet:ipv6-prefix
| | | +--rw reserved-prefix-len? uint8
| | +--rw option-set-id* leafref
| | +--rw valid-lifetime?
| | | dhc6:timer-seconds32
| | +--rw renew-time?
| | | dhc6:timer-seconds32
| | +--rw rebind-time?
| | | dhc6:timer-seconds32
| | +--rw preferred-lifetime?
| | | dhc6:timer-seconds32
| | +--rw rapid-commit? boolean
| +--ro active-leases
| +--ro total-count uint64
| +--ro allocated-count uint64
| +--ro active-lease* [leased-prefix]
| +--ro leased-prefix
| | inet:ipv6-prefix
| +--ro client-duid? dhc6:duid
| +--ro ia-id uint32
| +--ro allocation-time?
| | yang:date-and-time
| +--ro last-renew-rebind?
| | yang:date-and-time
Farrer Expires 22 May 2022 [Page 9]
Internet-Draft DHCPv6 YANG Model November 2021
| +--ro preferred-lifetime?
| | dhc6:timer-seconds32
| +--ro valid-lifetime?
| | dhc6:timer-seconds32
| +--ro lease-t1?
| | dhc6:timer-seconds32
| +--ro lease-t2?
| | dhc6:timer-seconds32
| +--ro status
| +--ro code? uint16
| +--ro message? string
+--ro solicit-count? uint32
+--ro advertise-count? uint32
+--ro request-count? uint32
+--ro confirm-count? uint32
+--ro renew-count? uint32
+--ro rebind-count? uint32
+--ro reply-count? uint32
+--ro release-count? uint32
+--ro decline-count? uint32
+--ro reconfigure-count? uint32
+--ro information-request-count? uint32
rpcs:
+---x delete-address-lease {na-assignment}?
| +---w input
| | +---w lease-address-to-delete leafref
| +--ro output
| +--ro return-message? string
+---x delete-prefix-lease {prefix-delegation}?
+---w input
| +---w lease-prefix-to-delete leafref
+--ro output
+--ro return-message? string
notifications:
+---n address-pool-utilization-threshold-exceeded
| {na-assignment}?
| +--ro pool-id leafref
| +--ro total-pool-addresses uint64
| +--ro max-allocated-addresses uint64
| +--ro allocated-address-count uint64
+---n prefix-pool-utilization-threshold-exceeded
| {prefix-delegation}?
| +--ro pool-id leafref
| +--ro total-pool-prefixes uint64
| +--ro max-allocated-prefixes uint64
| +--ro allocated-prefixes-count uint64
Farrer Expires 22 May 2022 [Page 10]
Internet-Draft DHCPv6 YANG Model November 2021
+---n invalid-client-detected
| +--ro message-type? enumeration
| +--ro duid? dhc6:duid
| +--ro description? string
+---n decline-received {na-assignment}?
| +--ro duid? dhc6:duid
| +--ro declined-resources* []
| +--ro (resource-type)?
| +--:(declined-address)
| | +--ro address? inet:ipv6-address
| +--:(declined-prefix)
| +--ro prefix? inet:ipv6-prefix
+---n non-success-code-sent
+--ro duid? dhc6:duid
+--ro status
+--ro code? uint16
+--ro message? string
Figure 1: DHCPv6 Server Data Module Structure
Descriptions of important nodes:
* enabled: Enables/disables the function of the DHCPv6 server.
* dhcpv6-server: This container holds the server's DHCPv6 specific
configuration.
* server-duid: Each server must have a DUID (DHCP Unique Identifier)
to identify itself to clients. A DUID consists of a two-octet
type field and an arbitrary length (of no more than 128-octets)
content field. Currently there are four defined types of DUIDs in
[RFC8415] and [RFC6355]. The DUID may be configured using the
format for one of these types, or using the 'unstructured' format.
The DUID type definitions are imported from the 'ietf-
dhcpv6-common.yang' module. [IANA-HARDWARE-TYPES] and [IANA-PEN]
are referenced for the relevant DUID types.
* vendor-config: This container is provided as a location for
additional implementation-specific YANG nodes for the
configuration of the device to be augmented. See Appendix C for
an example of such a module.
* option-sets: The server can be configured with multiple option-
sets. These are groups of DHCPv6 options with common parameters
which will be supplied to clients on request. The 'option-set-id'
field is used to reference an option-set elsewhere in the server's
configuration.
Farrer Expires 22 May 2022 [Page 11]
Internet-Draft DHCPv6 YANG Model November 2021
* option-set: Holds configuration parameters for DHCPv6 options.
The initial set of applicable option definitions are defined here
and additional options that are also relevant to the relay and/or
client are imported from the 'ietf-dhcpv6-common' module. Where
needed, other DHCPv6 option modules can be augmented as they are
defined.
* class-selector: This is provided as a location for additional
implementation specific YANG nodes for vendor specific class
selector nodes to be augmented. See Appendix D for an example of
this.
* allocation-ranges: A hierarchical model is used for the allocation
of addresses and prefixes. At the top level 'allocation-ranges'
container holds global configuration parameters. Under this, the
'allocation-range' list is used for specifying IPv6 prefixes and
additional, prefix specific parameters.
* address-pools: Used for IA_NA and IA_TA pool allocations with a
container for defining host reservations. State information about
active leases from the pool is also located here.
* prefix-pools: Defines pools to be used for prefix delegation to
clients. Static host reservations can also be configured. As
prefix delegation is not supported by all DHCPv6 server
implementations, it is enabled by a feature statement.
Information about RPCs
* delete-address-lease: Allows the deletion of a lease for an
individual IPv6 address from the server's lease database.
* delete-prefix-lease: Allows the deletion of a lease for an
individual IPv6 prefix from the server's lease database.
Information about notifications:
* address/prefix-pool-utilization-threshold-exceeded: Raised when
the number of leased addresses or prefixes exceeds the configured
usage threshold.
* invalid-client-detected: Raised when the server detects an invalid
client. A description of the error and message type that has
generated the notification can be included.
* decline-received: Raised when a DHCPv6 Decline message is received
from a client.
Farrer Expires 22 May 2022 [Page 12]
Internet-Draft DHCPv6 YANG Model November 2021
* non-success-code-sent: Raised when there is a status message for
an failure.
3.2. DHCPv6 Relay Tree Diagram
The tree diagram in Figure 2 provides an overview of the DHCPv6 relay
module. The tree also includes the common functions module
Section 4.1.
module: ietf-dhcpv6-relay
+--rw dhcpv6-relay
+--rw enabled? boolean
+--rw relay-if* [if-name]
| +--rw if-name
| | if:interface-ref
| +--rw enabled? boolean
| +--rw destination-address*
| | inet:ipv6-address
| +--rw link-address?
| | inet:ipv6-address
| +--rw relay-options
| | +--rw auth-option
| | | +--rw protocol? uint8
| | | +--rw algorithm? uint8
| | | +--rw rdm? uint8
| | | +--rw replay-detection? uint64
| | | +--rw auth-information? string
| | +--rw interface-id-option
| | +--rw interface-id? string
| +--ro solicit-received-count? uint32
| +--ro advertise-sent-count? uint32
| +--ro request-received-count? uint32
| +--ro confirm-received-count? uint32
| +--ro renew-received-count? uint32
| +--ro rebind-received-count? uint32
| +--ro reply-sent-count? uint32
| +--ro release-received-count? uint32
| +--ro decline-received-count? uint32
| +--ro reconfigure-sent-count? uint32
| +--ro information-request-received-count? uint32
| +--ro unknown-message-received-count? uint32
| +--ro unknown-message-sent-count? uint32
| +--ro discarded-message-count? uint32
| +--rw prefix-delegation! {prefix-delegation}?
| +--ro pd-leases* [ia-pd-prefix]
| +--ro ia-pd-prefix inet:ipv6-prefix
| +--ro last-renew? yang:date-and-time
| +--ro client-peer-address? inet:ipv6-address
Farrer Expires 22 May 2022 [Page 13]
Internet-Draft DHCPv6 YANG Model November 2021
| +--ro client-duid? dhc6:duid
| +--ro server-duid? dhc6:duid
+--ro relay-forward-sent-count? uint32
+--ro relay-forward-received-count? uint32
+--ro relay-reply-received-count? uint32
+--ro relay-forward-unknown-sent-count? uint32
+--ro relay-forward-unknown-received-count? uint32
+--ro discarded-message-count? uint32
rpcs:
+---x clear-prefix-entry {prefix-delegation}?
| +---w input
| | +---w lease-prefix leafref
| +--ro output
| +--ro return-message? string
+---x clear-client-prefixes {prefix-delegation}?
| +---w input
| | +---w client-duid dhc6:duid
| +--ro output
| +--ro return-message? string
+---x clear-interface-prefixes {prefix-delegation}?
+---w input
| +---w interface
| -> ../../dhcpv6-relay/relay-if/if-name
+--ro output
+--ro return-message? string
notifications:
+---n relay-event
+--ro topology-change
+--ro relay-if-name?
| -> ../../../dhcpv6-relay/relay-if/if-name
+--ro last-ipv6-addr? inet:ipv6-address
Figure 2: DHCPv6 Relay Data Module Structure
Descriptions of important nodes:
* enabled: Globally enables/disables all DHCPv6 relay functions.
* dhcpv6-relay: This container holds the relay's DHCPv6-specific
configuration.
* relay-if: As a relay may have multiple client-facing interfaces,
they are configured in a list. The if-name leaf is the key and is
an interface-ref to the applicable interface defined by the 'ietf-
interfaces' YANG module.
Farrer Expires 22 May 2022 [Page 14]
Internet-Draft DHCPv6 YANG Model November 2021
* enabled: Enables/disables all DHCPv6 relay function for the
specific interface.
* destination-addresses: Defines a list of IPv6 addresses that
client messages will be relayed to. May include unicast or
multicast addresses.
* link-address: Configures the value that the relay will put into
the link-address field of Relay-Forward messages.
* prefix-delegation: As prefix delegation is not supported by all
DHCPv6 relay implementations, it is enabled by this feature
statement where required.
* pd-leases: Contains read-only nodes for holding information about
active delegated prefix leases.
* relay-options: Holds configuration parameters for DHCPv6 options
which can be sent by the relay. The initial set of applicable
option definitions are defined here and additional options that
are also relevant to the server and/or client are imported from
the 'ietf-dhcpv6-common' module. Where needed, other DHCPv6
option modules can be augmented as they are defined.
Information about RPCs
* clear-prefix-lease: Allows the removal of a delegated lease entry
from the relay.
* clear-client-prefixes: Allows the removal of all of the delegated
lease entries for a single client (referenced by client DUID) from
the relay.
* clear-interface-prefixes: Allows the removal of all of the
delegated lease entries from an interface on the relay.
Information about notifications:
* topology-changed: Raised when the topology of the relay agent is
changed, e.g., a client facing interface is reconfigured.
3.3. DHCPv6 Client Tree Diagram
The tree diagram in Figure 3 provides an overview of the DHCPv6
client module. The tree also includes the common functions module
defined in Section 4.1.
Farrer Expires 22 May 2022 [Page 15]
Internet-Draft DHCPv6 YANG Model November 2021
module: ietf-dhcpv6-client
+--rw dhcpv6-client
+--rw enabled? boolean
+--rw client-duid? dhc6:duid
| {non-temp-addr or prefix-del or temp-addr
| and not anon-profile}?
+--rw client-if* [if-name]
+--rw if-name if:interface-ref
+--rw enabled? boolean
+--rw interface-duid? dhc6:duid
| {non-temp-addr or prefix-del or temp-addr
| and anon-profile}?
+--rw client-configured-options
| +--rw option-request-option
| | +--rw oro-option* uint16
| +--rw rapid-commit-option!
| +--rw user-class-option!
| | +--rw user-class-data-instance*
| | [user-class-data-id]
| | +--rw user-class-data-id uint8
| | +--rw user-class-data? string
| +--rw vendor-class-option
| | +--rw vendor-class-option-instances*
| | [enterprise-number]
| | +--rw enterprise-number uint32
| | +--rw vendor-class-data-element*
| | [vendor-class-data-id]
| | +--rw vendor-class-data-id uint8
| | +--rw vendor-class-data? string
| +--rw vendor-specific-information-options
| | +--rw vendor-specific-information-option*
| | [enterprise-number]
| | +--rw enterprise-number uint32
| | +--rw vendor-option-data* [sub-option-code]
| | +--rw sub-option-code uint16
| | +--rw sub-option-data? string
| +--rw reconfigure-accept-option!
+--rw ia-na* [ia-id] {non-temp-addr}?
| +--rw ia-id uint32
| +--rw ia-na-options
| +--ro lease-state
| +--ro ia-na-address? inet:ipv6-address
| +--ro lease-t1? dhc6:timer-seconds32
| +--ro lease-t2? dhc6:timer-seconds32
| +--ro preferred-lifetime? dhc6:timer-seconds32
| +--ro valid-lifetime? dhc6:timer-seconds32
| +--ro allocation-time? yang:date-and-time
| +--ro last-renew-rebind? yang:date-and-time
Farrer Expires 22 May 2022 [Page 16]
Internet-Draft DHCPv6 YANG Model November 2021
| +--ro server-duid? dhc6:duid
| +--ro status
| +--ro code? uint16
| +--ro message? string
+--rw ia-ta* [ia-id] {temp-addr}?
| +--rw ia-id uint32
| +--rw ia-ta-options
| +--ro lease-state
| +--ro ia-ta-address? inet:ipv6-address
| +--ro preferred-lifetime? dhc6:timer-seconds32
| +--ro valid-lifetime? dhc6:timer-seconds32
| +--ro allocation-time? yang:date-and-time
| +--ro last-renew-rebind? yang:date-and-time
| +--ro server-duid? dhc6:duid
| +--ro status
| +--ro code? uint16
| +--ro message? string
+--rw ia-pd* [ia-id] {prefix-del}?
| +--rw ia-id uint32
| +--rw prefix-length-hint? uint8
| +--rw ia-pd-options
| +--ro lease-state
| +--ro ia-pd-prefix? inet:ipv6-prefix
| +--ro lease-t1? dhc6:timer-seconds32
| +--ro lease-t2? dhc6:timer-seconds32
| +--ro preferred-lifetime? dhc6:timer-seconds32
| +--ro valid-lifetime? dhc6:timer-seconds32
| +--ro allocation-time? yang:date-and-time
| +--ro last-renew-rebind? yang:date-and-time
| +--ro server-duid? dhc6:duid
| +--ro status
| +--ro code? uint16
| +--ro message? string
+--ro solicit-count? uint32
+--ro advertise-count? uint32
+--ro request-count? uint32
+--ro confirm-count? uint32
+--ro renew-count? uint32
+--ro rebind-count? uint32
+--ro reply-count? uint32
+--ro release-count? uint32
+--ro decline-count? uint32
+--ro reconfigure-count? uint32
+--ro information-request-count? uint32
notifications:
+---n invalid-ia-address-detected
| {non-temp-addr or temp-addr}?
Farrer Expires 22 May 2022 [Page 17]
Internet-Draft DHCPv6 YANG Model November 2021
| +--ro ia-id uint32
| +--ro ia-na-t1-timer? uint32
| +--ro ia-na-t2-timer? uint32
| +--ro invalid-address? inet:ipv6-address
| +--ro preferred-lifetime? uint32
| +--ro valid-lifetime? uint32
| +--ro ia-options? binary
| +--ro description? string
+---n transmission-failed
| +--ro failure-type enumeration
| +--ro description? string
+---n unsuccessful-status-code
| +--ro server-duid dhc6:duid
| +--ro status
| +--ro code? uint16
| +--ro message? string
+---n server-duid-changed
{non-temp-addr or prefix-del or temp-addr}?
+--ro new-server-duid dhc6:duid
+--ro previous-server-duid dhc6:duid
+--ro lease-ia-na?
| -> ../../dhcpv6-client/client-if/ia-na/ia-id
| {non-temp-addr}?
+--ro lease-ia-ta?
| -> ../../dhcpv6-client/client-if/ia-ta/ia-id
| {temp-addr}?
+--ro lease-ia-pd?
-> ../../dhcpv6-client/client-if/ia-pd/ia-id
{prefix-del}?
Figure 3: DHCPv6 Client Data Module Structure
Descriptions of important nodes:
* enabled: Globally enables/disables all DHCPv6 client functions.
* dhcpv6-client: This container holds the client's DHCPv6 specific
configuration.
* client-if: As a client may have multiple interfaces requesting
configuration over DHCP, they are configured in a list. The if-
name leaf is the key and is an interface-ref to the applicable
interface defined by the 'ietf-interfaces' YANG module.
* enabled: Enables/disables all DHCPv6 client function for the
specific interface.
Farrer Expires 22 May 2022 [Page 18]
Internet-Draft DHCPv6 YANG Model November 2021
* client-duid/interface-duid: The DUID (DHCP Unique Identifier) is
used to identify the client to servers and relays. DUID
configuration may conditionally appear in one of two locations in
the client tree, depending on the features that the client
implements. If the client does not support requesting any address
or prefix leasing features, then there is no leaf for a DUID
value. If the client does not implement the 'anon-profile'
feature [RFC7844], then there is a single 'client-duid' leaf that
holds that DUID value which will be used for all DHCPv6 enabled
interfaces. If the 'anon-profile' is enabled, there is an
'interface-duid' leaf for each DHCP enabled interface. A DUID
consists of a two-octet type field and an arbitrary length (1-128
octets) content field. Currently there are four defined types of
DUIDs in [RFC8415] and [RFC6355]. The DUID may be configured
using the format for one of these types, or using the
'unstructured' format. The DUID type definitions are imported
from the 'ietf-dhcpv6-common.yang' module. [IANA-HARDWARE-TYPES]
and [IANA-PEN] are referenced for the relevant DUID types.
* client-configured-options: Holds configuration parameters for
DHCPv6 options which can be sent by the client. The initial set
of applicable option definitions are defined here and additional
options that are also relevant to the relay and/or server are
imported from the 'ietf-dhcpv6-common' module. Where needed,
other DHCPv6 option modules can be augmented as they are defined.
* ia-na, ia-ta, ia-pd: Contains configuration nodes relevant for
requesting one or more of each of the lease types. Read-only
nodes related to the active leases for each type are also located
here. As these lease types may not be supported by all DHCPv6
client implementations, they are enabled via individual feature
statements. Stateless DHCP ([RFC8415] Section 6.1) is configured
when all address and prefix features are disabled.
Information about notifications:
* invalid-ia-detected: Raised when the identity association of the
client can be proved to be invalid. Possible conditions include:
duplicated address, illegal address, etc.
* retransmission-failed: Raised when the retransmission mechanism
defined in [RFC8415] has failed.
Farrer Expires 22 May 2022 [Page 19]
Internet-Draft DHCPv6 YANG Model November 2021
4. DHCPv6 YANG Modules
4.1. DHCPv6 Common YANG Module
This module imports typedefs from [RFC6991].
<CODE BEGINS> file "ietf-dhcpv6-common@2021-11-18.yang"
module ietf-dhcpv6-common {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-dhcpv6-common";
prefix "dhc6";
organization
"IETF DHC (Dynamic Host Configuration) Working Group";
contact
"WG Web: <https://datatracker.ietf.org/wg/dhc/>
WG List: <mailto:dhcwg@ietf.org>
Author: Yong Cui <yong@csnet1.cs.tsinghua.edu.cn>
Author: Linhui Sun <lh.sunlinh@gmail.com>
Editor: Ian Farrer <ian.farrer@telekom.de>
Author: Sladjana Zeichlin <sladjana.zechlin@telekom.de>
Author: Zihao He <hezihao9512@gmail.com>
Author: Michal Nowikowski <godfryd@isc.org>";
description
"This YANG module defines common components used for the
configuration and management of DHCPv6.
The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL',
'SHALL NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED',
'NOT RECOMMENDED', 'MAY', and 'OPTIONAL' in this document
are to be interpreted as described in BCP 14 (RFC 2119)
(RFC 8174) when, and only when, they appear in all
capitals, as shown here.
Copyright (c) 2021 IETF Trust and the persons identified as
authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject
to the license terms contained in, the Simplified BSD License
set forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see
Farrer Expires 22 May 2022 [Page 20]
Internet-Draft DHCPv6 YANG Model November 2021
the RFC itself for full legal notices.";
revision 2021-10-25 {
description
"Initial Revision.";
reference
"XXXX: YANG Data Model for DHCPv6 Configuration";
}
typedef threshold {
type uint8 {
range 1..100;
}
description
"Threshold value in percent.";
}
typedef timer-seconds32 {
type uint32;
units "seconds";
description
"Timer value type, in seconds (32-bit range).";
}
typedef duid-base {
type string {
pattern '([0-9a-fA-F]{2}){3,130}';
}
description
"Each DHCP server and client has a DUID (DHCP Unique
Identifier). The DUID consists of a two-octet
type field and an arbitrary length (1-128 octets) content
field. The duid-base type is used by other duid types with
additional pattern constraints.
Currently, there are four defined types of DUIDs
in RFC 8415 and RFC 6355 - DUID-LLT, DUID-EN, DUID-LL
and DUID-UUID. DUID-unstructured represents DUIDs which
do not follow any of the defined formats.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 11
RFC 6355: Definition of the UUID-Based DHCPv6 Unique
Identifier (DUID-UUID), Section 4";
}
typedef duid-llt {
type duid-base {
pattern '0001'
Farrer Expires 22 May 2022 [Page 21]
Internet-Draft DHCPv6 YANG Model November 2021
+ '[0-9a-fA-F]{12,}';
}
description
"DUID type 1, based on Link-Layer Address Plus Time
(DUID-LLT). Constructed with a 2-octet hardware type assigned
by IANA, 4-octet containing the time the DUID is generated
(represented in seconds since midnight (UTC), January 1, 2000,
modulo 2^32), and a link-layer address. The address is encoded
without separator characters. For example:
+------+------+----------+--------------+
| 0001 | 0006 | 28490058 | 00005E005300 |
+------+------+----------+--------------+
This example includes the 2-octet DUID type of 1 (0x01), the
hardware type is 0x06 (IEEE Hardware Types) the creation
time is 0x028490058 (constructed as described above). Finally,
the link-layer address is 0x5E005300 (EUI-48 address
00-00-5E-00-53-00)";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 11.2
IANA 'Hardware Types' registry.
<https://www.iana.org/assignments/arp-parameters>";
}
typedef duid-en {
type duid-base {
pattern '0002'
+ '[0-9a-fA-F]{4,}';
}
description
"DUID type 2, assigned by vendor based on Enterprise
Number (DUID-EN). This DUID consists of the 4-octet vendor's
registered Private Enterprise Number as maintained by IANA
followed by a unique identifier assigned by the vendor. For
example:
+------+----------+------------------+
| 0002 | 00007ED9 | 0CC084D303000912 |
+------+----------+------------------+
This example includes the 2-octet DUID type of 2 (0x02),
4-octets for the Enterprise Number (0x7ED9), followed by
8-octets of identifier data (0x0CC084D303000912).";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 11.3
IANA 'Private Enterprise Numbers' registry.
<https://www.iana.org/assignments/enterprise-numbers>";
Farrer Expires 22 May 2022 [Page 22]
Internet-Draft DHCPv6 YANG Model November 2021
}
typedef duid-ll {
type duid-base {
pattern '0003'
+ '([0-9a-fA-F]){4,}';
}
description
"DUID type 3, based on Link-Layer Address (DUID-LL).
Constructed with a 2-octet hardware type assigned
by IANA, and a link-layer address. The address is encoded
without separator characters. For example:
+------+------+--------------+
| 0003 | 0006 | 00005E005300 |
+------+------+--------------+
This example includes the 2-octet DUID type of 3 (0x03), the
hardware type is 0x06 (IEEE Hardware Types), and the link-layer
address is 0x5E005300 (EUI-48 address 00-00-5E-00-53-00)";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 11.4
IANA 'Hardware Types' registry.
<https://www.iana.org/assignments/arp-parameters>";
}
typedef duid-uuid {
type duid-base {
pattern '0004'
+ '[0-9a-fA-F]{32}';
}
description
"DUID type 4, based on Universally Unique Identifier
(DUID-UUID). This type of DUID consists of 16 octets
containing a 128-bit UUID. For example:
+------+----------------------------------+
| 0004 | 9f03b182705747e38a1e422910078642 |
+------+----------------------------------+
This example includes the 2-octet DUID type of 4 (0x04), and
the UUID 9f03b182-7057-47e3-8a1e-422910078642.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 11.5
RFC 6355: Definition of the UUID-Based DHCPv6 Unique Identifier
(DUID-UUID)";
Farrer Expires 22 May 2022 [Page 23]
Internet-Draft DHCPv6 YANG Model November 2021
}
typedef duid-unstructured {
type duid-base {
pattern '(000[1-4].*|.*[^0-9a-fA-F].*)' {
modifier invert-match;
}
}
description
"Used for DUIDs following any other formats than DUID
types 1-4. For example:
+----------------------------------+
| 7b6a164d325946539dc540fb539bc430 |
+----------------------------------+
Here, an arbitrary 16-octet value is used. The only constraint
placed on this is that the first 2-octects are not 0x01-0x04
to avoid collision with the other defined DUID types
(duid-llt, duid-en, duid-ll, or duid-uuid).";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 11";
}
typedef duid {
type union {
type duid-llt;
type duid-en;
type duid-ll;
type duid-uuid;
type duid-unstructured;
}
description
"Represents the DUID and is neutral to the DUID's construction
format.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 11";
}
/*
* Groupings
*/
grouping status {
description
"Holds information about the most recent status code which
has been sent by the server or received by the client.";
reference "RFC 8415: Dynamic Host Configuration Protocol
Farrer Expires 22 May 2022 [Page 24]
Internet-Draft DHCPv6 YANG Model November 2021
for IPv6 (DHCPv6), Section 7.5.";
container status {
description
"Status code information, relating to the success or failure
of operations requested in messages.";
leaf code {
type uint16;
description
"The numeric code for the status encoded in this option.
See the Status Codes registry at
<https://www.iana.org/assignments/dhcpv6-parameters>
for the current list of status codes.";
}
leaf message {
type string;
description
"A UTF-8 encoded text string suitable for display to an
end user. It MUST NOT be null-terminated.";
}
}
}
grouping auth-option-group {
description
"OPTION_AUTH (11) Authentication Option.";
reference "RFC 8415: Dynamic Host Configuration Protocol
for IPv6 (DHCPv6), Section 21.11
IANA 'Dynamic Host Configuration Protocol (DHCP) Authentication
Option Name Spaces' registry.
<https://www.iana.org/assignments/auth-namespaces>";
container auth-option {
description
"OPTION_AUTH (11) Authentication Option container.";
leaf protocol {
type uint8;
description
"The authentication protocol used by this Authentication
option.";
}
leaf algorithm {
type uint8;
description
"The algorithm used in the authentication protocol.";
}
leaf rdm {
type uint8;
description
Farrer Expires 22 May 2022 [Page 25]
Internet-Draft DHCPv6 YANG Model November 2021
"The Replay Detection Method (RDM) used in this
Authentication option.";
}
leaf replay-detection {
type uint64;
description
"The replay detection information for the RDM.";
}
leaf auth-information {
type string;
description
"The authentication information, as specified by the
protocol and algorithm used in this Authentication
option.";
}
}
}
grouping status-code-option-group {
description
"OPTION_STATUS_CODE (13) Status Code Option.";
reference "RFC 8415: Dynamic Host Configuration Protocol
for IPv6 (DHCPv6), Section 21.13";
container status-code-option {
description
"OPTION_STATUS_CODE (13) Status Code Option container.";
leaf status-code {
type uint16;
description
"The numeric code for the status encoded in this option.
See the Status Codes registry at
<https://www.iana.org/assignments/dhcpv6-parameters>
for the current list of status codes.";
}
leaf status-message {
type string;
description
"A UTF-8 encoded text string suitable for display to an
end user. It MUST NOT be null-terminated.";
}
}
}
grouping rapid-commit-option-group {
description
"OPTION_RAPID_COMMIT (14) Rapid Commit Option.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 21.14";
Farrer Expires 22 May 2022 [Page 26]
Internet-Draft DHCPv6 YANG Model November 2021
container rapid-commit-option {
presence "Enable sending of this option";
description
"OPTION_RAPID_COMMIT (14) Rapid Commit Option container.";
}
}
grouping vendor-specific-information-option-group {
description
"OPTION_VENDOR_OPTS (17) Vendor-specific Information
Option.";
reference "RFC 8415: Dynamic Host Configuration Protocol
for IPv6 (DHCPv6), Section 21.17";
container vendor-specific-information-options {
description
"OPTION_VENDOR_OPTS (17) Vendor-specific Information
Option container.";
list vendor-specific-information-option {
key enterprise-number;
description
"The vendor-specific information option allows for
multiple instances in a single message. Each list entry
defines the contents of an instance of the option.";
leaf enterprise-number {
type uint32;
description
"The vendor's registered Enterprise Number, as
maintained by IANA.";
reference "IANA 'Private Enterprise Numbers' registry.
<https://www.iana.org/assignments/enterprise-numbers>";
}
list vendor-option-data {
key sub-option-code;
description
"Vendor options, interpreted by vendor-specific
client/server functions.";
leaf sub-option-code {
type uint16;
description
"The code for the sub-option.";
}
leaf sub-option-data {
type string {
pattern '([0-9a-fA-F]{2}){0,}';
}
description
"The data area for the sub-option.";
}
Farrer Expires 22 May 2022 [Page 27]
Internet-Draft DHCPv6 YANG Model November 2021
}
}
}
}
grouping reconfigure-accept-option-group {
description
"OPTION_RECONF_ACCEPT (20) Reconfigure Accept Option.
A client uses the Reconfigure Accept option to announce to
the server whether the client is willing to accept Reconfigure
messages, and a server uses this option to tell the client
whether or not to accept Reconfigure messages. In the absence
of this option, the default behavior is that the client is
unwilling to accept Reconfigure messages. The presence node
is used to enable the option.";
reference "RFC 8415: Dynamic Host Configuration Protocol
for IPv6 (DHCPv6), Section 21.20";
container reconfigure-accept-option {
presence "Enable sending of this option";
description
"OPTION_RECONF_ACCEPT (20) Reconfigure Accept Option
container.";
}
}
}
<CODE ENDS>
4.2. DHCPv6 Server YANG Module
This module imports typedefs from [RFC6991], [RFC8343].
<CODE BEGINS> file "ietf-dhcpv6-server@2021-11-18.yang"
module ietf-dhcpv6-server {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-dhcpv6-server";
prefix "dhc6-srv";
import ietf-inet-types {
prefix inet;
reference
"RFC 6991: Common YANG Data Types";
}
import ietf-yang-types {
prefix yang;
reference
"RFC 6991: Common YANG Data Types";
Farrer Expires 22 May 2022 [Page 28]
Internet-Draft DHCPv6 YANG Model November 2021
}
import ietf-dhcpv6-common {
prefix dhc6;
reference
"RFC XXXX: To be updated on publication";
}
import ietf-netconf-acm {
prefix nacm;
reference
"RFC 8341: Network Configuration Access Control Model";
}
organization
"IETF DHC (Dynamic Host Configuration) Working Group";
contact
"WG Web: <https://datatracker.ietf.org/wg/dhc/>
WG List: <mailto:dhcwg@ietf.org>
Author: Yong Cui <yong@csnet1.cs.tsinghua.edu.cn>
Author: Linhui Sun <lh.sunlinh@gmail.com>
Editor: Ian Farrer <ian.farrer@telekom.de>
Author: Sladjana Zeichlin <sladjana.zechlin@telekom.de>
Author: Zihao He <hezihao9512@gmail.com>
Author: Michal Nowikowski <godfryd@isc.org>";
description
"This YANG module defines components for the configuration
and management of DHCPv6 servers.
Copyright (c) 2021 IETF Trust and the persons identified as
authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject
to the license terms contained in, the Simplified BSD License
set forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see
the RFC itself for full legal notices.";
revision 2021-10-25 {
description
"Initial Revision.";
reference
Farrer Expires 22 May 2022 [Page 29]
Internet-Draft DHCPv6 YANG Model November 2021
"XXXX: YANG Data Model for DHCPv6 Configuration";
}
/*
* Features
*/
feature na-assignment {
description
"Denotes that the server implements DHCPv6 non-temporary
address assignment.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 6.2";
}
feature prefix-delegation {
description
"Denotes that the server implements DHCPv6 prefix
delegation.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 6.3";
}
/*
* Groupings
*/
grouping resource-config {
description
"Nodes that are reused at multiple levels in the DHCPv6
server's addressing hierarchy.";
leaf-list option-set-id {
type leafref {
path "/dhcpv6-server/option-sets/option-set/option-set-id";
}
description
"The ID field of relevant set of DHCPv6 options (option-set)
to be provisioned to clients using the allocation-range.";
}
leaf valid-lifetime {
type dhc6:timer-seconds32;
description
"Valid lifetime for the Identity Association (IA).";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 6";
}
leaf renew-time {
type dhc6:timer-seconds32;
Farrer Expires 22 May 2022 [Page 30]
Internet-Draft DHCPv6 YANG Model November 2021
description
"Renew (T1) time.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 4.2";
}
leaf rebind-time {
type dhc6:timer-seconds32;
description
"Rebind (T2) time.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 4.2";
}
leaf preferred-lifetime {
type dhc6:timer-seconds32;
description
"Preferred lifetime for the Identity Association (IA).";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 6";
}
leaf rapid-commit {
type boolean;
description
"When set to 'true', Specifies that the pool supports
client-server exchanges involving two messages.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 5.1";
}
}
grouping lease-information {
description
"Binding information for each client that has been allocated
an IPv6 address or prefix.";
leaf client-duid {
type dhc6:duid;
description
"Client DUID.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 11";
}
leaf ia-id {
type uint32;
mandatory true;
description
"Client's IAID";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 12";
}
Farrer Expires 22 May 2022 [Page 31]
Internet-Draft DHCPv6 YANG Model November 2021
leaf allocation-time {
type yang:date-and-time;
description
"Time and date that the lease was made.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 18";
}
leaf last-renew-rebind {
type yang:date-and-time;
description
"Time of the last successful renew or rebind.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 18";
}
leaf preferred-lifetime {
type dhc6:timer-seconds32;
description
"The preferred lifetime expressed in seconds.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 6";
}
leaf valid-lifetime {
type dhc6:timer-seconds32;
description
"The valid lifetime for the lease expressed in seconds.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 6";
}
leaf lease-t1 {
type dhc6:timer-seconds32;
description
"The time interval after which the client should contact
the server from which the addresses in the IA_NA were
obtained to extend the lifetimes of the addresses assigned
to the IA_PD.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 4.2";
}
leaf lease-t2 {
type dhc6:timer-seconds32;
description
"The time interval after which the client should contact
any available server to extend the lifetimes of the
addresses assigned to the IA_PD.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 4.2";
}
uses dhc6:status;
Farrer Expires 22 May 2022 [Page 32]
Internet-Draft DHCPv6 YANG Model November 2021
}
grouping message-stats {
description
"Counters for DHCPv6 messages.";
leaf solicit-count {
type uint32;
config "false";
description
"Number of Solicit (1) messages received.";
}
leaf advertise-count {
type uint32;
config "false";
description
"Number of Advertise (2) messages sent.";
}
leaf request-count {
type uint32;
config "false";
description
"Number of Request (3) messages received.";
}
leaf confirm-count {
type uint32;
config "false";
description
"Number of Confirm (4) messages received.";
}
leaf renew-count {
type uint32;
config "false";
description
"Number of Renew (5) messages received.";
}
leaf rebind-count {
type uint32;
config "false";
description
"Number of Rebind (6) messages received.";
}
leaf reply-count {
type uint32;
config "false";
description
"Number of Reply (7) messages sent.";
}
leaf release-count {
Farrer Expires 22 May 2022 [Page 33]
Internet-Draft DHCPv6 YANG Model November 2021
type uint32;
config "false";
description
"Number of Release (8) messages received.";
}
leaf decline-count {
type uint32;
config "false";
description
"Number of Decline (9) messages received.";
}
leaf reconfigure-count {
type uint32;
config "false";
description
"Number of Reconfigure (10) messages sent.";
}
leaf information-request-count {
type uint32;
config "false";
description
"Number of Information-request (11) messages
received.";
}
}
grouping preference-option-group {
description
"OPTION_PREFERENCE (7) Preference Option.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 21.8";
container preference-option {
description
"OPTION_PREFERENCE (7) Preference Option
container.";
leaf pref-value {
type uint8;
description
"The preference value for the server in this
message. A 1-octet unsigned integer.";
}
}
}
grouping server-unicast-option-group {
description
"OPTION_UNICAST (12) Server Unicast Option.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
Farrer Expires 22 May 2022 [Page 34]
Internet-Draft DHCPv6 YANG Model November 2021
IPv6 (DHCPv6), Section 21.12";
container server-unicast-option {
description
"OPTION_UNICAST (12) Server Unicast Option container.";
leaf server-address {
type inet:ipv6-address;
description
"The 128-bit address to which the client should send
messages delivered using unicast.";
}
}
}
grouping reconfigure-message-option-group {
description
"OPTION_RECONF_MSG (19) Reconfigure Message Option.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 21.19";
container reconfigure-message-option {
description
"OPTION_RECONF_MSG (19) Reconfigure Message Option.";
leaf msg-type {
type uint8;
description
"5 for Renew message, 6 for Rebind message, 11 for
Information-request message.";
}
}
}
grouping info-refresh-time-option-group {
description
"OPTION_INFORMATION_REFRESH_TIME (32) Information Refresh
Time Option.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 21.23";
container info-refresh-time-option {
description
"OPTION_INFORMATION_REFRESH_TIME (32)
Information Refresh Time option container.";
leaf info-refresh-time {
type dhc6:timer-seconds32;
description
"Time duration relative to the current time, expressed
in units of seconds.";
}
}
}
Farrer Expires 22 May 2022 [Page 35]
Internet-Draft DHCPv6 YANG Model November 2021
grouping sol-max-rt-option-group {
description
"OPTION_SOL_MAX_RT (82) SOL_MAX_RT Option (Max Solicit timeout
value).";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 21.24";
container sol-max-rt-option {
description
"OPTION_SOL_MAX_RT (82) SOL_MAX_RT option container.";
leaf sol-max-rt-value {
type dhc6:timer-seconds32;
description
"sol max rt value";
}
}
}
grouping inf-max-rt-option-group {
description
"OPTION_INF_MAX_RT (83) INF_MAX_RT Option (Max
Information-request timeout value).";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 21.25";
container inf-max-rt-option {
description
"OPTION_INF_MAX_RT (83) inf max rt option
container.";
leaf inf-max-rt-value {
type dhc6:timer-seconds32;
description
"inf max rt value";
}
}
}
/*
* Data Nodes
*/
container dhcpv6-server {
description
"Configuration nodes for the DHCPv6 server.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 18.3";
leaf enabled {
type boolean;
description
"Enables the DHCP server function.";
Farrer Expires 22 May 2022 [Page 36]
Internet-Draft DHCPv6 YANG Model November 2021
}
leaf server-duid {
type dhc6:duid;
description
"DUID of the server.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 11";
}
container vendor-config {
description
"This container provides a location for
augmenting vendor or implementation specific
configuration nodes.";
}
container option-sets {
description
"A server may allow different option sets
to be configured for clients matching specific parameters
such as topological location or client type. The
'option-set' list is a set of options and their
contents that will be returned to clients.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 21";
list option-set {
key option-set-id;
description
"YANG definitions for DHCPv6 options are
contained in separate YANG modules and augmented to this
container as required.";
leaf option-set-id {
type uint32;
description
"Option set identifier.";
}
leaf description {
type string;
description
"An optional field for storing additional information
relevant to the option set.";
}
uses preference-option-group;
uses dhc6:auth-option-group;
uses server-unicast-option-group;
uses dhc6:rapid-commit-option-group;
uses dhc6:vendor-specific-information-option-group;
uses reconfigure-message-option-group;
uses dhc6:reconfigure-accept-option-group;
uses info-refresh-time-option-group;
Farrer Expires 22 May 2022 [Page 37]
Internet-Draft DHCPv6 YANG Model November 2021
uses sol-max-rt-option-group;
uses inf-max-rt-option-group;
}
}
container class-selector {
description
"DHCPv6 servers use a 'class-selector' function in order
to identify and classify incoming client messages
so that they can be given the correct configuration.
The mechanisms used for implementing this function vary
greatly between different implementations such it is not
possible to include in this module. This container provides
a location for server implementors to augment their own
class-selector YANG.";
}
container allocation-ranges {
description
"This model is based on an address and parameter
allocation hierarchy. The top level is 'global' - which
is defined as the container for all allocation-ranges. Under
this are the individual allocation-ranges.";
uses resource-config;
list allocation-range {
key id;
description
"Network-ranges are identified by the 'id' key.";
leaf id {
type uint32;
mandatory true;
description
"Unique identifier for the allocation range.";
}
leaf description {
type string;
description
"Description for the allocation range.";
}
leaf network-prefix {
type inet:ipv6-prefix;
mandatory true;
description
"Network prefix.";
}
uses resource-config;
container address-pools {
if-feature na-assignment;
Farrer Expires 22 May 2022 [Page 38]
Internet-Draft DHCPv6 YANG Model November 2021
description
"Configuration for the DHCPv6 server's
address pools.";
list address-pool {
key pool-id;
description
"List of address pools for allocation to clients,
distinguished by 'pool-id'.";
leaf pool-id {
type string;
mandatory true;
description
"Unique identifier for the pool.";
}
leaf pool-prefix {
type inet:ipv6-prefix;
mandatory true;
description
"IPv6 prefix for the pool.";
}
leaf start-address {
type inet:ipv6-address-no-zone;
mandatory true;
description
"Starting IPv6 address for the pool.";
}
leaf end-address {
type inet:ipv6-address-no-zone;
mandatory true;
description
"Ending IPv6 address for the pool.";
}
leaf max-address-utilization {
type dhc6:threshold;
description
"Maximum amount of the addresses in the
pool which can be simultaneously allocated,
calculated as a percentage of the available
addresses (end-address minus start-address plus
one).";
}
uses resource-config;
container host-reservations {
description
"Configuration for host reservations from the
address pool.";
list host-reservation {
key reserved-addr;
Farrer Expires 22 May 2022 [Page 39]
Internet-Draft DHCPv6 YANG Model November 2021
description
"List of host reservations.";
leaf client-duid {
type dhc6:duid;
description
"Client DUID for the reservation.";
}
leaf reserved-addr {
type inet:ipv6-address;
description
"Reserved IPv6 address.";
}
uses resource-config;
}
}
container active-leases {
config false;
description
"Holds state related to active client
leases.";
leaf total-count {
type uint64;
mandatory true;
description
"The total number of addresses in the
pool.";
}
leaf allocated-count {
type uint64;
mandatory true;
description
"The number of addresses or prefixes
in the pool that are currently allocated.";
}
list active-lease {
key leased-address;
description
"List of active address leases.";
leaf leased-address {
type inet:ipv6-address;
description
"Active address lease entry.";
}
uses lease-information;
}
}
}
}
Farrer Expires 22 May 2022 [Page 40]
Internet-Draft DHCPv6 YANG Model November 2021
container prefix-pools {
if-feature prefix-delegation;
description
"Configuration for the DHCPv6 server's prefix pools.";
list prefix-pool {
key pool-id;
description
"List of prefix pools for allocation to
clients, distinguished by 'pool-id'.";
leaf pool-id {
type string;
mandatory true;
description
"Unique identifier for the pool.";
}
leaf pool-prefix {
type inet:ipv6-prefix;
mandatory true;
description
"IPv6 prefix for the pool.";
}
leaf client-prefix-length {
type uint8 {
range "1 .. 128";
}
mandatory true;
description
"Length of the prefixes that will be delegated
to clients.";
}
leaf max-pd-space-utilization {
type dhc6:threshold;
description
"Maximum amount of the prefixes in the
pool which can be simultaneously allocated,
calculated as a percentage of the available
prefixes, rounded up.";
}
uses resource-config;
container host-reservations {
description
"Configuration for host reservations from the
prefix pool.";
list prefix-reservation {
key reserved-prefix;
description
"Reserved prefix reservation.";
leaf client-duid {
Farrer Expires 22 May 2022 [Page 41]
Internet-Draft DHCPv6 YANG Model November 2021
type dhc6:duid;
description
"Client DUID for the reservation.";
}
leaf reserved-prefix {
type inet:ipv6-prefix;
description
"Reserved IPv6 prefix";
}
leaf reserved-prefix-len {
type uint8;
description
"Reserved IPv6 prefix length.";
}
}
uses resource-config;
}
container active-leases {
config false;
description
"Holds state related to active client prefix
leases.";
leaf total-count {
type uint64;
mandatory true;
description
"The total number of prefixes in the pool.";
}
leaf allocated-count {
type uint64;
mandatory true;
description
"The number of prefixes in the pool that are
currently allocated.";
}
list active-lease {
key leased-prefix;
description
"List of active prefix leases.";
leaf leased-prefix {
type inet:ipv6-prefix;
description
"Active leased prefix entry.";
}
uses lease-information;
}
}
}
Farrer Expires 22 May 2022 [Page 42]
Internet-Draft DHCPv6 YANG Model November 2021
}
}
uses message-stats;
}
}
/*
* RPCs
*/
rpc delete-address-lease {
nacm:default-deny-all;
if-feature na-assignment;
description
"Deletes a client's active address lease from the
server's lease database. Note this will not cause the address
to be revoked from the client, and the lease may be refreshed
or renewed by the client.";
input {
leaf lease-address-to-delete {
type leafref {
path "../../dhcpv6-server/allocation-ranges/" +
"allocation-range/address-pools/address-pool" +
"/active-leases/active-lease/leased-address";
}
mandatory true;
description
"IPv6 address of an active lease that will be
deleted from the server.";
}
}
output {
leaf return-message {
type string;
description
"Response message from the server.";
}
}
}
rpc delete-prefix-lease {
nacm:default-deny-all;
if-feature prefix-delegation;
description
"Deletes a client's active prefix lease from the
server's lease database. Note, this will not cause the prefix
to be revoked from the client, and the lease may be refreshed
or renewed by the client.";
Farrer Expires 22 May 2022 [Page 43]
Internet-Draft DHCPv6 YANG Model November 2021
input {
leaf lease-prefix-to-delete {
type leafref {
path "../../dhcpv6-server/allocation-ranges/" +
"allocation-range/prefix-pools/prefix-pool" +
"/active-leases/active-lease/leased-prefix";
}
mandatory true;
description
"IPv6 prefix of an active lease that will be deleted
from the server.";
}
}
output {
leaf return-message {
type string;
description
"Response message from the server.";
}
}
}
/*
* Notifications
*/
notification address-pool-utilization-threshold-exceeded {
if-feature na-assignment;
description
"Notification sent when the address pool
utilization exceeds the threshold configured in
max-address-utilization.";
leaf pool-id {
type leafref {
path "../../dhcpv6-server/allocation-ranges/" +
"allocation-range/address-pools/address-pool" +
"/pool-id";
}
mandatory true;
description
"Leafref to the address pool that the notification
is being generated for.";
}
leaf total-pool-addresses {
type uint64;
mandatory true;
description
"Total number of addresses in the pool
Farrer Expires 22 May 2022 [Page 44]
Internet-Draft DHCPv6 YANG Model November 2021
(end-address minus start-address plus one).";
}
leaf max-allocated-addresses {
type uint64;
mandatory true;
description
"Maximum number of addresses that can be simultaneously
allocated from the pool. This value may be less than
count of total addresses. Calculated as the
max-address-utilization (percentage) of the
total-pool-addresses, rounded up.";
}
leaf allocated-address-count {
type uint64;
mandatory true;
description
"Number of addresses allocated from the pool.";
}
}
notification prefix-pool-utilization-threshold-exceeded {
if-feature prefix-delegation;
description
"Notification sent when the prefix pool utilization
exceeds the threshold configured in
max-pd-space-utilization.";
leaf pool-id {
type leafref {
path "../../dhcpv6-server/allocation-ranges" +
"/allocation-range/prefix-pools/prefix-pool/pool-id";
}
mandatory true;
description
"Unique identifier for the pool.";
}
leaf total-pool-prefixes {
type uint64;
mandatory true;
description
"Total number of prefixes in the pool.";
}
leaf max-allocated-prefixes {
type uint64;
mandatory true;
description
"Maximum number of prefixes that can be simultaneously
allocated from the pool. This value may be less than
count of total prefixes. Calculated as the
Farrer Expires 22 May 2022 [Page 45]
Internet-Draft DHCPv6 YANG Model November 2021
max-prefix-utilization (percentage) of the
total-pool-prefixes, rounded up.";
}
leaf allocated-prefixes-count {
type uint64;
mandatory true;
description
"Number of prefixes allocated from the pool.";
}
}
notification invalid-client-detected {
description
"Notification sent when the server detects an
invalid client.";
leaf message-type {
type enumeration {
enum solicit {
description
"Solicit (1) message.";
}
enum request {
description
"Request (3) message.";
}
enum confirm {
description
"Confirm (4) message.";
}
enum renew {
description
"Renew (5) message.";
}
enum rebind {
description
"Rebind (6) message.";
}
enum release {
description
"Release (8) message.";
}
enum decline {
description
"Decline (9) message.";
}
enum info-request {
description
"Information request (11) message.";
Farrer Expires 22 May 2022 [Page 46]
Internet-Draft DHCPv6 YANG Model November 2021
}
}
description
"The message type received by the server that has caused
the error.";
}
leaf duid {
type dhc6:duid;
description
"Client DUID.";
}
leaf description {
type string;
description
"Description of the event (e.g., and error code or log
message).";
}
}
notification decline-received {
if-feature na-assignment;
description
"Notification sent when the server has received a
Decline (9) message from a client.";
leaf duid {
type dhc6:duid;
description
"Client DUID.";
}
list declined-resources {
description
"List of declined addresses and/or prefixes.";
choice resource-type {
description
"Type of resource that has been declined.";
case declined-address {
leaf address {
type inet:ipv6-address;
description
"Address that has been declined.";
}
}
case declined-prefix {
leaf prefix {
type inet:ipv6-prefix;
description
"Prefix that has been declined.";
}
Farrer Expires 22 May 2022 [Page 47]
Internet-Draft DHCPv6 YANG Model November 2021
}
}
}
}
notification non-success-code-sent {
description
"Notification sent when the server responded
to a client with non-success status code.";
leaf duid {
type dhc6:duid;
description
"Client DUID.";
}
uses dhc6:status;
}
}
<CODE ENDS>
4.3. DHCPv6 Relay YANG Module
This module imports typedefs from [RFC6991], [RFC8343].
<CODE BEGINS> file "ietf-dhcpv6-relay@2021-11-18.yang"
module ietf-dhcpv6-relay {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-dhcpv6-relay";
prefix "dhc6-rly";
import ietf-inet-types {
prefix inet;
reference
"RFC 6991: Common YANG Data Types";
}
import ietf-yang-types {
prefix yang;
reference
"RFC 6991: Common YANG Data Types";
}
import ietf-dhcpv6-common {
prefix dhc6;
reference
"RFC XXXX: To be updated on publication";
}
Farrer Expires 22 May 2022 [Page 48]
Internet-Draft DHCPv6 YANG Model November 2021
import ietf-interfaces {
prefix if;
reference
"RFC 8343: A YANG Data Model for Interface Management";
}
import ietf-netconf-acm {
prefix nacm;
reference
"RFC 8341: Network Configuration Access Control Model";
}
organization
"IETF DHC (Dynamic Host Configuration) Working Group";
contact
"WG Web: <https://datatracker.ietf.org/wg/dhc/>
WG List: <mailto:dhcwg@ietf.org>
Author: Yong Cui <yong@csnet1.cs.tsinghua.edu.cn>
Author: Linhui Sun <lh.sunlinh@gmail.com>
Editor: Ian Farrer <ian.farrer@telekom.de>
Author: Sladjana Zeichlin <sladjana.zechlin@telekom.de>
Author: Zihao He <hezihao9512@gmail.com>
Author: Michal Nowikowski <godfryd@isc.org>";
description
"This YANG module defines components necessary for the
configuration and management of DHCPv6 relays.
Copyright (c) 2021 IETF Trust and the persons identified as
authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject
to the license terms contained in, the Simplified BSD License
set forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see
the RFC itself for full legal notices.";
revision 2021-10-25 {
description
"Initial Revision.";
reference
"XXXX: YANG Data Model for DHCPv6 Configuration";
}
Farrer Expires 22 May 2022 [Page 49]
Internet-Draft DHCPv6 YANG Model November 2021
/*
* Features
*/
feature prefix-delegation {
description
"Enable if the relay functions as a delegating router for
DHCPv6 prefix delegation.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 6.3";
}
/*
* Groupings
*/
grouping pd-lease-state {
description
"State data for the relay.";
list pd-leases {
key ia-pd-prefix;
config false;
description
"Information about an active IA_PD prefix
delegation.";
leaf ia-pd-prefix {
type inet:ipv6-prefix;
description
"Prefix that is delegated.";
}
leaf last-renew {
type yang:date-and-time;
description
"Time of the last successful refresh or renew of the
delegated prefix.";
}
leaf client-peer-address {
type inet:ipv6-address;
description
"Peer-address of the leasing client.";
}
leaf client-duid {
type dhc6:duid;
description
"DUID of the leasing client.";
}
leaf server-duid {
type dhc6:duid;
Farrer Expires 22 May 2022 [Page 50]
Internet-Draft DHCPv6 YANG Model November 2021
description
"DUID of the delegating server.";
}
}
}
grouping message-statistics {
description
"Contains counters for the different DHCPv6
message types.";
leaf solicit-received-count {
type uint32;
config "false";
description
"Number of Solicit (1) messages received.";
}
leaf advertise-sent-count {
type uint32;
config "false";
description
"Number of Advertise (2) messages sent.";
}
leaf request-received-count {
type uint32;
config "false";
description
"Number of Request (3) messages received.";
}
leaf confirm-received-count {
type uint32;
config "false";
description
"Number of Confirm (4) messages received.";
}
leaf renew-received-count {
type uint32;
config "false";
description
"Number of Renew (5) messages received.";
}
leaf rebind-received-count {
type uint32;
config "false";
description
"Number of Rebind (6) messages received.";
}
leaf reply-sent-count {
type uint32;
Farrer Expires 22 May 2022 [Page 51]
Internet-Draft DHCPv6 YANG Model November 2021
config "false";
description
"Number of Reply (7) messages received.";
}
leaf release-received-count {
type uint32;
config "false";
description
"Number of Release (8) messages sent.";
}
leaf decline-received-count {
type uint32;
config "false";
description
"Number of Decline (9) messages sent.";
}
leaf reconfigure-sent-count {
type uint32;
config "false";
description
"Number of Reconfigure (10) messages sent.";
}
leaf information-request-received-count {
type uint32;
config "false";
description
"Number of Information-request (11) messages
received.";
}
leaf unknown-message-received-count {
type uint32;
config "false";
description
"Number of messages of unknown type that have
been received.";
}
leaf unknown-message-sent-count {
type uint32;
config "false";
description
"Number of messages of unknown type that have
been sent.";
}
leaf discarded-message-count {
type uint32;
config "false";
description
"Number of messages that have been discarded
Farrer Expires 22 May 2022 [Page 52]
Internet-Draft DHCPv6 YANG Model November 2021
for any reason.";
}
}
grouping global-statistics {
description
"Global statistics for the device.";
leaf relay-forward-sent-count {
type uint32;
config "false";
description
"Number of Relay-forward (12) messages sent.";
}
leaf relay-forward-received-count {
type uint32;
config "false";
description
"Number of Relay-forward (12) messages received.";
}
leaf relay-reply-received-count {
type uint32;
config "false";
description
"Number of Relay-reply (13) messages received.";
}
leaf relay-forward-unknown-sent-count {
type uint32;
config "false";
description
"Number of Relay-forward (12) messages containing
a message of unknown type sent.";
}
leaf relay-forward-unknown-received-count {
type uint32;
config "false";
description
"Number of Relay-forward (12) messages containing
a message of unknown type received.";
}
leaf discarded-message-count {
type uint32;
config "false";
description
"Number of messages that have been discarded
for any reason.";
}
}
Farrer Expires 22 May 2022 [Page 53]
Internet-Draft DHCPv6 YANG Model November 2021
grouping interface-id-option-group {
description
"OPTION_INTERFACE_ID (18) Interface-Id Option.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 21.18";
container interface-id-option {
description
"OPTION_INTERFACE_ID (18) Interface-Id Option
container.";
leaf interface-id {
type string;
description
"An opaque value of arbitrary length generated by the
relay agent to identify one of the relay agent's
interfaces.";
}
}
}
/*
* Data Nodes
*/
container dhcpv6-relay {
description
"This container contains the configuration data nodes
for the relay.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 19";
leaf enabled {
type boolean;
description
"Globally enables the DHCP relay function.";
}
list relay-if {
key if-name;
description
"List of interfaces configured for DHCPv6
relaying.";
leaf if-name {
type if:interface-ref;
description
"interface-ref to the relay interface.";
}
leaf enabled {
type boolean;
description
"Enables the DHCP relay function for this
Farrer Expires 22 May 2022 [Page 54]
Internet-Draft DHCPv6 YANG Model November 2021
interface.";
}
leaf-list destination-address {
type inet:ipv6-address;
description
"Each DHCPv6 relay agent may be configured with a list
of destination addresses for relayed messages.
The list may include unicast addresses, multicast
addresses or other valid addresses.";
}
leaf link-address {
type inet:ipv6-address;
description
"An address that may be used by the server to identify
the link on which the client is located.";
}
container relay-options {
description
"Definitions for DHCPv6 options that can be sent
by the relay are augmented to this location from other
YANG modules as required.";
uses dhc6:auth-option-group;
uses interface-id-option-group;
}
uses message-statistics;
container prefix-delegation {
if-feature prefix-delegation;
presence "Enables prefix delegation for this interface.";
description
"Controls and holds state information for prefix
delegation.";
uses pd-lease-state;
}
}
uses global-statistics;
}
/*
* RPCs
*/
rpc clear-prefix-entry {
nacm:default-deny-all;
if-feature prefix-delegation;
description
"Clears an entry for an active delegated prefix
from the relay.";
reference "RFC8987: DHCPv6 Prefix Delegating Relay Requirements,
Farrer Expires 22 May 2022 [Page 55]
Internet-Draft DHCPv6 YANG Model November 2021
Section 4.4";
input {
leaf lease-prefix {
type leafref {
path "../../dhcpv6-relay/relay-if/prefix-delegation" +
"/pd-leases/ia-pd-prefix";
}
mandatory true;
description
"IPv6 prefix of an active lease entry that will
be deleted from the relay.";
}
}
output {
leaf return-message {
type string;
description
"Response message from the relay.";
}
}
}
rpc clear-client-prefixes {
nacm:default-deny-all;
if-feature prefix-delegation;
description
"Clears all active prefix entries for a single client.";
reference "RFC8987: DHCPv6 Prefix Delegating Relay Requirements,
Section 4.4";
input {
leaf client-duid {
type dhc6:duid;
mandatory true;
description
"DUID of the client.";
}
}
output {
leaf return-message {
type string;
description
"Response message from the relay.";
}
}
}
rpc clear-interface-prefixes {
nacm:default-deny-all;
Farrer Expires 22 May 2022 [Page 56]
Internet-Draft DHCPv6 YANG Model November 2021
if-feature prefix-delegation;
description
"Clears all delegated prefix bindings from an
interface on the relay.";
reference "RFC8987: DHCPv6 Prefix Delegating Relay Requirements,
Section 4.4";
input {
leaf interface {
type leafref {
path "../../dhcpv6-relay/relay-if/if-name";
}
mandatory true;
description
"Reference to the relay interface that will have all
active prefix delegation bindings deleted.";
}
}
output {
leaf return-message {
type string;
description
"Response message from the relay.";
}
}
}
/*
* Notifications
*/
notification relay-event {
description
"DHCPv6 relay event notifications.";
container topology-change {
description
"Raised if the entry for an interface with DHCPv6
related configuration or state is removed from
if:interface-refs.";
leaf relay-if-name {
type leafref {
path "../../../dhcpv6-relay/relay-if/if-name";
}
description
"Name of the interface that has been removed.";
}
leaf last-ipv6-addr {
type inet:ipv6-address;
description
Farrer Expires 22 May 2022 [Page 57]
Internet-Draft DHCPv6 YANG Model November 2021
"Last IPv6 address configured on the interface.";
}
}
}
}
<CODE ENDS>
4.4. DHCPv6 Client YANG Module
This module imports typedefs from [RFC6991], [RFC8343].
<CODE BEGINS> file "ietf-dhcpv6-client@2021-11-18.yang"
module ietf-dhcpv6-client {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-dhcpv6-client";
prefix "dhc6-clnt";
import ietf-inet-types {
prefix inet;
reference
"RFC 6991: Common YANG Data Types";
}
import ietf-yang-types {
prefix yang;
reference
"RFC 6991: Common YANG Data Types";
}
import ietf-dhcpv6-common {
prefix dhc6;
reference
"RFC XXXX: To be updated on publication";
}
import ietf-interfaces {
prefix if;
reference
"RFC 8343: A YANG Data Model for Interface Management";
}
organization
"IETF DHC (Dynamic Host Configuration) Working Group";
contact
"WG Web: <https://datatracker.ietf.org/wg/dhc/>
WG List: <mailto:dhcwg@ietf.org>
Farrer Expires 22 May 2022 [Page 58]
Internet-Draft DHCPv6 YANG Model November 2021
Author: Yong Cui <yong@csnet1.cs.tsinghua.edu.cn>
Author: Linhui Sun <lh.sunlinh@gmail.com>
Editor: Ian Farrer <ian.farrer@telekom.de>
Author: Sladjana Zeichlin <sladjana.zechlin@telekom.de>
Author: Zihao He <hezihao9512@gmail.com>
Author: Michal Nowikowski <godfryd@isc.org>";
description
"This YANG module defines components necessary for the
configuration and management of DHCPv6 clients.
The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL',
'SHALL NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED',
'NOT RECOMMENDED', 'MAY', and 'OPTIONAL' in this document
are to be interpreted as described in BCP 14 (RFC 2119)
(RFC 8174) when, and only when, they appear in all
capitals, as shown here.
Copyright (c) 2021 IETF Trust and the persons identified as
authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject
to the license terms contained in, the Simplified BSD License
set forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see
the RFC itself for full legal notices.";
revision 2021-10-25 {
description
"Initial Revision.";
reference
"XXXX: YANG Data Model for DHCPv6 Configuration";
}
/*
* Features
*/
feature non-temp-addr {
description
"Denotes that the client supports DHCPv6 non-temporary address
allocations.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 6.2";
Farrer Expires 22 May 2022 [Page 59]
Internet-Draft DHCPv6 YANG Model November 2021
}
feature prefix-del {
description
"Denotes that the client implements DHCPv6 prefix
delegation.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 6.3";
}
feature temp-addr {
description
"Denotes that the client supports DHCPv6 temporary address
allocations.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 6.5";
}
feature anon-profile {
description
"Denotes that the client supports DHCP anonymity
profiles.";
reference "RFC 7844: Anonymity Profiles for DHCP Clients";
}
/*
* Groupings
*/
grouping message-statistics {
description
"Counters for DHCPv6 messages.";
leaf solicit-count {
type uint32;
config "false";
description
"Number of Solicit (1) messages sent.";
}
leaf advertise-count {
type uint32;
config "false";
description
"Number of Advertise (2) messages received.";
}
leaf request-count {
type uint32;
config "false";
description
Farrer Expires 22 May 2022 [Page 60]
Internet-Draft DHCPv6 YANG Model November 2021
"Number of Request (3) messages sent.";
}
leaf confirm-count {
type uint32;
config "false";
description
"Number of Confirm (4) messages sent.";
}
leaf renew-count {
type uint32;
config "false";
description
"Number of Renew (5) messages sent.";
}
leaf rebind-count {
type uint32;
config "false";
description
"Number of Rebind (6) messages sent.";
}
leaf reply-count {
type uint32;
config "false";
description
"Number of Reply (7) messages received.";
}
leaf release-count {
type uint32;
config "false";
description
"Number of Release (8) messages sent.";
}
leaf decline-count {
type uint32;
config "false";
description
"Number of Decline (9) messages sent.";
}
leaf reconfigure-count {
type uint32;
config "false";
description
"Number of Reconfigure (10) messages received.";
}
leaf information-request-count {
type uint32;
config "false";
description
Farrer Expires 22 May 2022 [Page 61]
Internet-Draft DHCPv6 YANG Model November 2021
"Number of Information-request (11) messages
sent.";
}
}
grouping lease-state {
description
"Information about the active IA_NA lease.";
leaf preferred-lifetime {
type dhc6:timer-seconds32;
description
"The preferred lifetime for the leased address
expressed in seconds.";
}
leaf valid-lifetime {
type dhc6:timer-seconds32;
description
"The valid lifetime for the leased address expressed
in seconds.";
}
leaf allocation-time {
type yang:date-and-time;
description
"Time and date that the address was first leased.";
}
leaf last-renew-rebind {
type yang:date-and-time;
description
"Time of the last successful renew or rebind of the
leased address.";
}
leaf server-duid {
type dhc6:duid;
description
"DUID of the leasing server.";
}
uses dhc6:status;
}
grouping option-request-option-group {
description
"OPTION_ORO (6) Option Request Option. A client MUST include
an Option Request option in a Solicit, Request, Renew,
Rebind, or Information-request message to inform the server
about options the client wants the server to send to the
client.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 21.7";
Farrer Expires 22 May 2022 [Page 62]
Internet-Draft DHCPv6 YANG Model November 2021
container option-request-option {
description
"OPTION_ORO (6) Option Request Option container.";
leaf-list oro-option {
type uint16;
description
"List of options that the client is requesting,
identified by option code";
}
}
}
grouping user-class-option-group {
description
"OPTION_USER_CLASS (15) User Class Option";
reference "RFC 8415: Dynamic Host Configuration Protocol
for IPv6 (DHCPv6), Section 21.15";
container user-class-option {
presence "Configures the option";
description
"OPTION_USER_CLASS (15) User Class Option
container.";
list user-class-data-instance {
key user-class-data-id;
min-elements 1;
description
"The user classes of which the client
is a member.";
leaf user-class-data-id {
type uint8;
description
"User class data ID";
}
leaf user-class-data {
type string;
description
"Opaque field representing a User Class
of which the client is a member.";
}
}
}
}
grouping vendor-class-option-group {
description
"OPTION_VENDOR_CLASS (16) Vendor Class Option";
reference "RFC 8415: Dynamic Host Configuration Protocol
for IPv6 (DHCPv6), Section 21.16";
Farrer Expires 22 May 2022 [Page 63]
Internet-Draft DHCPv6 YANG Model November 2021
container vendor-class-option {
description
"OPTION_VENDOR_CLASS (16) Vendor Class Option
container.";
list vendor-class-option-instances {
key enterprise-number;
description
"The vendor class option allows for multiple
instances in a single message. Each list entry defines
the contents of an instance of the option.";
leaf enterprise-number {
type uint32;
description
"The vendor's registered Enterprise Number as
maintained by IANA.";
}
list vendor-class-data-element {
key vendor-class-data-id;
description
"The vendor classes of which the client is a member.";
leaf vendor-class-data-id {
type uint8;
description
"Vendor class data ID";
}
leaf vendor-class-data {
type string;
description
"Opaque field representing a vendor class of which
the client is a member.";
}
}
}
}
}
/*
* Data Nodes
*/
container dhcpv6-client {
description
"DHCPv6 client configuration and state.";
leaf enabled {
type boolean;
default true;
description
"Globally enables the DHCP client function.";
Farrer Expires 22 May 2022 [Page 64]
Internet-Draft DHCPv6 YANG Model November 2021
}
leaf client-duid {
if-feature "non-temp-addr or prefix-del " +
"or temp-addr and not anon-profile";
type dhc6:duid;
description
"A single Client DUID that will be used by all of the
client's DHCPv6 enabled interfaces.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 11";
}
list client-if {
key if-name;
description
"The list of interfaces for which the client will
be requesting DHCPv6 configuration.";
leaf if-name {
type if:interface-ref;
mandatory true;
description
"Reference to the interface entry that the requested
configuration is relevant to.";
}
leaf enabled {
type boolean;
default true;
description
"Enables the DHCP client function for this interface.";
}
leaf interface-duid {
if-feature "non-temp-addr or prefix-del " +
"or temp-addr and anon-profile";
type dhc6:duid;
description
"Per-interface Client DUIDs for use with DHCP anonymity
profiles.";
reference "RFC 7844: Anonymity Profiles for DHCP Clients,
Section 3";
}
container client-configured-options {
description
"Definitions for DHCPv6 options that can be be sent by
the client. Additional option definitions can be
augmented to this location from other YANG modules as
required.";
uses option-request-option-group;
uses dhc6:rapid-commit-option-group;
uses user-class-option-group;
Farrer Expires 22 May 2022 [Page 65]
Internet-Draft DHCPv6 YANG Model November 2021
uses vendor-class-option-group;
uses dhc6:vendor-specific-information-option-group;
uses dhc6:reconfigure-accept-option-group;
}
list ia-na {
if-feature non-temp-addr;
key ia-id;
description
"Configuration relevant for an IA_NA (Identity Association
for Non-temporary Addresses).";
reference "RFC 8415: Dynamic Host Configuration Protocol
for IPv6 (DHCPv6), Section 13.1";
leaf ia-id {
type uint32;
description
"A unique identifier for this IA_NA.";
reference "RFC 8415: Dynamic Host Configuration Protocol
for IPv6 (DHCPv6), Section 12";
}
container ia-na-options {
description
"An augmentation point for additional options
that the client may send in the IA_NA-options field
of OPTION_IA_NA.";
}
container lease-state {
config false;
description
"Information about the active IA_NA lease.";
leaf ia-na-address {
type inet:ipv6-address;
description
"Address that is currently leased.";
}
leaf lease-t1 {
type dhc6:timer-seconds32;
description
"The time interval after which the client should
contact the server from which the addresses in the
IA_NA were obtained to extend the lifetimes of the
addresses assigned to the IA_NA.";
}
leaf lease-t2 {
type dhc6:timer-seconds32;
description
"The time interval after which the client should
contact any available server to extend the lifetimes
of the addresses assigned to the IA_NA.";
Farrer Expires 22 May 2022 [Page 66]
Internet-Draft DHCPv6 YANG Model November 2021
}
uses lease-state;
}
}
list ia-ta {
if-feature temp-addr;
key ia-id;
description
"Configuration relevant for an IA_TA (Identity Association
for Temporary Addresses).";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 13.2";
leaf ia-id {
type uint32;
description
"The unique identifier for this IA_TA.";
reference "RFC 8415: Dynamic Host Configuration Protocol
for IPv6 (DHCPv6), Section 12";
}
container ia-ta-options {
description
"An augmentation point for additional options
that the client may send in the IA_TA-options field
of OPTION_IA_TA.";
}
container lease-state {
config "false";
description
"Information about an active IA_TA lease.";
leaf ia-ta-address {
type inet:ipv6-address;
description
"Address that is currently leased.";
}
uses lease-state;
}
}
list ia-pd {
if-feature prefix-del;
key ia-id;
description
"Configuration relevant for an IA_PD (Identity Association
for Prefix Delegation).";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 13.3";
leaf ia-id {
type uint32;
description
Farrer Expires 22 May 2022 [Page 67]
Internet-Draft DHCPv6 YANG Model November 2021
"The unique identifier for this IA_PD.";
reference "RFC 8415: Dynamic Host Configuration Protocol
for IPv6 (DHCPv6), Section 12";
}
leaf prefix-length-hint {
type uint8 {
range "1..128";
}
description "Prefix-length hint value included
in the messages sent to the server to indicate a
preference for the size of the prefix to be delegated.";
reference "RFC 8415: Dynamic Host Configuration Protocol
for IPv6 (DHCPv6), Section 18.2.1";
}
container ia-pd-options {
description
"An augmentation point for additional options that the
client will send in the IA_PD-options field of
OPTION_IA_TA.";
}
container lease-state {
config "false";
description
"Information about an active IA_PD delegated prefix.";
leaf ia-pd-prefix {
type inet:ipv6-prefix;
description
"Delegated prefix that is currently leased.";
}
leaf lease-t1 {
type dhc6:timer-seconds32;
description
"The time interval after which the client should
contact the server from which the addresses in the
IA_NA were obtained to extend the lifetimes of the
addresses assigned to the IA_PD.";
}
leaf lease-t2 {
type dhc6:timer-seconds32;
description
"The time interval after which the client should
contact any available server to extend the lifetimes
of the addresses assigned to the IA_PD.";
}
uses lease-state;
}
}
Farrer Expires 22 May 2022 [Page 68]
Internet-Draft DHCPv6 YANG Model November 2021
uses message-statistics;
}
}
/*
* Notifications
*/
notification invalid-ia-address-detected {
if-feature "non-temp-addr or temp-addr";
description
"Notification sent when an address received
in an identity association option is determined invalid.
Possible conditions include a duplicate or otherwise illegal
address.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 18.2.10.1";
leaf ia-id {
type uint32;
mandatory true;
description
"IA-ID";
}
leaf ia-na-t1-timer {
type uint32;
description
"The value of the T1 time field for non-temporary address
allocations (OPTION_IA_NA).";
}
leaf ia-na-t2-timer {
type uint32;
description
"The value of the preferred-lifetime field for non-temporary
address allocations (OPTION_IA_NA).";
}
leaf invalid-address {
type inet:ipv6-address;
description
"The IP address which has been detected to be invalid.";
}
leaf preferred-lifetime {
type uint32;
description
"The value of the preferred-lifetime field in
OPTION_IAADDR.";
}
leaf valid-lifetime {
type uint32;
Farrer Expires 22 May 2022 [Page 69]
Internet-Draft DHCPv6 YANG Model November 2021
description
"The value of the valid-lifetime field in OPTION_IAADDR.";
}
leaf ia-options {
type binary;
description
"A copy of the contents of the IAaddr-options field.";
}
leaf description {
type string;
description
"Description of the invalid Identity Association (IA)
detection error.";
}
}
notification transmission-failed {
description
"Notification sent when the transmission or retransmission
of a message fails.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 7.6";
leaf failure-type {
type enumeration {
enum "solicit-timeout" {
description
"Max Solicit timeout value (SOL_MAX_RT) exceeded.";
}
enum "request-timeout" {
description
"Max Request timeout value (REQ_MAX_RT) exceeded.";
}
enum "request-retries-exceeded" {
description
"Max Request retry attempts (REC_MAX_RC) exceeded.";
}
enum "confirm-duration-exceeded" {
description
"Max Confirm duration (CNF_MAX_RD) exceeded.";
}
enum "renew-timeout" {
description
"Max Renew timeout value (REN_MAX_RT) exceeded.";
}
enum "rebind-timeout" {
description
"Max Rebind timeout value (REB_MAX_RT)
exceeded.";
Farrer Expires 22 May 2022 [Page 70]
Internet-Draft DHCPv6 YANG Model November 2021
}
enum "info-request-timeout" {
description
"Max Information-request timeout value (INF_MAX_RT)
exceeded.";
}
enum "release-retries-exceeded" {
description
"Max Release retry attempts (REL_MAX_RC) exceeded.";
}
enum "decline-retries-exceeded" {
description
"Max Decline retry attempts (DEC_MAX_RT) exceeded.";
}
}
mandatory true;
description
"Description of the failure.";
}
leaf description {
type string;
description
"Information related to the failure, such as number of
retries and timer values.";
}
}
notification unsuccessful-status-code {
description
"Notification sent when the client receives a message that
includes an unsuccessful Status Code option.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 21.13";
leaf server-duid {
type dhc6:duid;
mandatory true;
description
"DUID of the server sending the unsuccessful
error code.";
}
uses dhc6:status;
}
notification server-duid-changed {
if-feature "non-temp-addr or prefix-del or " +
"temp-addr";
description
"Notification sent when the client receives a lease
Farrer Expires 22 May 2022 [Page 71]
Internet-Draft DHCPv6 YANG Model November 2021
from a server with different DUID to the one currently stored
by the client, e.g., in response to a Rebind message.";
reference "RFC 8415: Dynamic Host Configuration Protocol for
IPv6 (DHCPv6), Section 18.2.5";
leaf new-server-duid {
type dhc6:duid;
mandatory true;
description
"DUID of the new server.";
}
leaf previous-server-duid {
type dhc6:duid;
mandatory true;
description
"DUID of the previous server.";
}
leaf lease-ia-na {
if-feature non-temp-addr;
type leafref {
path "../../dhcpv6-client/client-if/ia-na/ia-id";
}
description
"Reference to the IA_NA lease.";
}
leaf lease-ia-ta {
if-feature temp-addr;
type leafref {
path "../../dhcpv6-client/client-if/ia-ta/ia-id";
}
description
"Reference to the IA_TA lease.";
}
leaf lease-ia-pd {
if-feature prefix-del;
type leafref {
path "../../dhcpv6-client/client-if/ia-pd/ia-id";
}
description
"Reference to the IA_PD lease.";
}
}
}
<CODE ENDS>
Farrer Expires 22 May 2022 [Page 72]
Internet-Draft DHCPv6 YANG Model November 2021
5. Security Considerations
The YANG modules defined in this document are designed to be accessed
via network management protocols such as NETCONF [RFC6241] or
RESTCONF [RFC8040]. The lowest NETCONF layer is the secure transport
layer, and the mandatory-to-implement secure transport is Secure
Shell (SSH) [RFC6242]. The lowest RESTCONF layer is HTTPS, and the
mandatory-to-implement secure transport is TLS [RFC8446].
The Network Configuration Access Control Model (NACM) [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.
All data nodes defined in the YANG modules which can be created,
modified, and deleted (i.e., config true, which is the default) are
considered sensitive. Write operations (e.g., edit-config) to these
data nodes without proper protection can have a negative effect on
network operations.
As the RPCs for deleting/clearing active address and prefix entries
in the server and relay modules are particularly sensitive, these use
'nacm:default-deny-all'.
An attacker with read/write access the DHCPv6 server can undertake
various attacks, such as:
* Denial of service attacks, based on re-configuring messages to a
rogue DHCPv6 server.
* Various attacks based on re-configuring the contents of DHCPv6
options, leading to several types of security or privacy threats.
For example, changing the address of a DNS server supplied in a
DHCP option to point to a rogue server.
An attacker with read/write access the DHCPv6 relay can undertake
various attacks, such as:
* Modifying the relay's "destination-address" to send messages to a
rogue DHCPv6 server.
* Deleting information about a client's delegated prefix, causing a
denial of service attack as traffic will no longer be routed to
the client.
Farrer Expires 22 May 2022 [Page 73]
Internet-Draft DHCPv6 YANG Model November 2021
Some of the readable data nodes in this YANG module may be considered
sensitive or vulnerable in some network environments. Therefore, it
is important to control read access (e.g., only permitting get, get-
config, or notifications) to these data nodes. These subtrees and
data nodes can be misused to track the activity of a host:
* Information the server holds about clients with active leases:
(dhc6-srv/allocation-ranges/allocation-range/address-pools/
address-pool/active-leases)
* Information the relay holds about clients with active leases:
(dhc6-rly/relay-if/prefix-delegation/)
[RFC7824] covers privacy considerations for DHCPv6 and is applicable
here.
Security considerations related to DHCPv6 are discussed in [RFC8415].
Security considerations given in [RFC7950] are also applicable here.
6. IANA Considerations
This document requests IANA to register the following URIs in the
"IETF XML Registry" [RFC3688]:
URI: urn:ietf:params:xml:ns:yang:ietf-dhcpv6-server
Registrant Contact: The IESG.
XML: N/A; the requested URI is an XML namespace.
URI: urn:ietf:params:xml:ns:yang:ietf-dhcpv6-relay
Registrant Contact: The IESG.
XML: N/A; the requested URI is an XML namespace.
URI: urn:ietf:params:xml:ns:yang:ietf-dhcpv6-client
Registrant Contact: The IESG.
XML: N/A; the requested URI is an XML namespace.
URI: urn:ietf:params:xml:ns:yang:ietf-dhcpv6-common
Registrant Contact: The IESG.
XML: N/A; the requested URI is an XML namespace.
This document registers the following YANG modules in the "YANG
Module Names" registry [RFC6020].
name: ietf-dhcpv6-server
namespace: urn:ietf:params:xml:ns:yang:ietf-dhcpv6-server
prefix: dhc6-srv
reference: RFC XXXX YANG Data Model for DHCPv6 Configuration
Farrer Expires 22 May 2022 [Page 74]
Internet-Draft DHCPv6 YANG Model November 2021
name: ietf-dhcpv6-relay
namespace: urn:ietf:params:xml:ns:yang:ietf-dhcpv6-relay
prefix: dhc6-rly
reference: RFC XXXX YANG Data Model for DHCPv6 Configuration
name: ietf-dhcpv6-client
namespace: urn:ietf:params:xml:ns:yang:ietf-dhcpv6-client
prefix: dhc6-clnt
reference: RFC XXXX YANG Data Model for DHCPv6 Configuration
name: ietf-dhcpv6-common
namespace: urn:ietf:params:xml:ns:yang:ietf-dhcpv6-common
prefix: dhc6
reference: RFC XXXX YANG Data Model for DHCPv6 Configuration
7. Acknowledgments
The authors would like to thank Qi Sun, Lishan Li, Hao Wang, Tomek
Mrugalski, Marcin Siodelski, Bernie Volz, Ted Lemon, Bing Liu, Tom
Petch, and Acee Lindem for their valuable comments and contributions
to this work.
8. Contributors
The following individuals are co-authors of this document:
Farrer Expires 22 May 2022 [Page 75]
Internet-Draft DHCPv6 YANG Model November 2021
Yong Cui
Tsinghua University
Beijing, 100084
P.R. China
Email: cuiyong@tsinghua.edu.cn
Linhui Sun
Tsinghua University
Beijing, 100084
P.R. China
Email: lh.sunlinh@gmail.com
Sladjana Zechlin
Deutsche Telekom AG
CTO-IPT, Landgrabenweg 151
53227, Bonn
Germany
Email: sladjana.zechlin@telekom.de
Zihao He
Tsinghua University
Beijing, 100084
P.R. China
Email: hezihao9512@gmail.com
Michal Nowikowski
Internet Systems Consortium
Gdansk
Poland
Email: godfryd@isc.org
9. References
9.1. Normative References
[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>.
Farrer Expires 22 May 2022 [Page 76]
Internet-Draft DHCPv6 YANG Model November 2021
[RFC6355] Narten, T. and J. Johnson, "Definition of the UUID-Based
DHCPv6 Unique Identifier (DUID-UUID)", RFC 6355,
DOI 10.17487/RFC6355, August 2011,
<https://www.rfc-editor.org/info/rfc6355>.
[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>.
[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>.
[RFC7844] Huitema, C., Mrugalski, T., and S. Krishnan, "Anonymity
Profiles for DHCP Clients", RFC 7844,
DOI 10.17487/RFC7844, May 2016,
<https://www.rfc-editor.org/info/rfc7844>.
[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>.
[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>.
[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>.
[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>.
[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>.
Farrer Expires 22 May 2022 [Page 77]
Internet-Draft DHCPv6 YANG Model November 2021
[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>.
[RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol
Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,
<https://www.rfc-editor.org/info/rfc8446>.
[RFC8415] Mrugalski, T., Siodelski, M., Volz, B., Yourtchenko, A.,
Richardson, M., Jiang, S., Lemon, T., and T. Winters,
"Dynamic Host Configuration Protocol for IPv6 (DHCPv6)",
RFC 8415, DOI 10.17487/RFC8415, November 2018,
<https://www.rfc-editor.org/info/rfc8415>.
[IANA-HARDWARE-TYPES]
Internet Assigned Numbers Authority, "Hardware Types",
<https://www.iana.org/assignments/arp-parameters>.
[IANA-PEN] Internet Assigned Numbers Authority, "Private Enterprise
Numbers",
<https://www.iana.org/assignments/enterprise-numbers>.
9.2. Informative References
[RFC3319] Schulzrinne, H. and B. Volz, "Dynamic Host Configuration
Protocol (DHCPv6) Options for Session Initiation Protocol
(SIP) Servers", RFC 3319, DOI 10.17487/RFC3319, July 2003,
<https://www.rfc-editor.org/info/rfc3319>.
[RFC7824] Krishnan, S., Mrugalski, T., and S. Jiang, "Privacy
Considerations for DHCPv6", RFC 7824,
DOI 10.17487/RFC7824, May 2016,
<https://www.rfc-editor.org/info/rfc7824>.
[RFC8987] Farrer, I., Kottapalli, N., Hunek, M., and R. Patterson,
"DHCPv6 Prefix Delegating Relay Requirements", RFC 8987,
DOI 10.17487/RFC8987, February 2021,
<https://www.rfc-editor.org/info/rfc8987>.
Appendix A. Data Tree Examples
This section contains XML examples of data trees for the different
DHCPv6 elements.
Farrer Expires 22 May 2022 [Page 78]
Internet-Draft DHCPv6 YANG Model November 2021
A.1. DHCPv6 Server Configuration Examples
The following example shows a basic configuration for a server. The
configuration defines:
* Enabling the DHCP server function
* The server's DUID
* An option set (id=1) with configuration for the Solicit Max Retry
Timeout (SOL_MAX_RT (82)) option.
* A single network range (2001:db8::/32)
* A single address pool, with start and end addresses, relevant
lease timers and an option-set-id of "1" referencing the option
set configured above.
Farrer Expires 22 May 2022 [Page 79]
Internet-Draft DHCPv6 YANG Model November 2021
<dhcpv6-server
xmlns="urn:ietf:params:xml:ns:yang:ietf-dhcpv6-server">
<enabled>true</enabled>
<server-duid>000200090CC084D303000912</server-duid>
<vendor-config/>
<option-sets>
<option-set>
<option-set-id>1</option-set-id>
<description>Example DHCP option set</description>
<sol-max-rt-option>
<sol-max-rt-value>3600</sol-max-rt-value>
</sol-max-rt-option>
</option-set>
</option-sets>
<class-selector/>
<allocation-ranges>
<valid-lifetime>54000</valid-lifetime>
<renew-time>7200</renew-time>
<rebind-time>32400</rebind-time>
<preferred-lifetime>43200</preferred-lifetime>
<allocation-range>
<id>1</id>
<description>example-allocation-range</description>
<network-prefix>2001:db8::/32</network-prefix>
<option-set-id>1</option-set-id>
<address-pools>
<address-pool>
<pool-id>1</pool-id>
<pool-prefix>2001:db8:1:1::/64</pool-prefix>
<start-address>2001:db8:1:1::1000</start-address>
<end-address>2001:db8:1:1::2000</end-address>
<max-address-utilization>50</max-address-utilization>
<option-set-id>1</option-set-id>
</address-pool>
</address-pools>
</allocation-range>
</allocation-ranges>
</dhcpv6-server>
Figure 4: Basic Server Configuration Example XML
The following example configuration snippet shows a static host
reservation within an address pool. The host's lease timers are
configured to be longer than hosts from the pool with dynamically
assigned addresses.
Farrer Expires 22 May 2022 [Page 80]
Internet-Draft DHCPv6 YANG Model November 2021
<address-pools>
<address-pool>
<pool-id>1</pool-id>
<pool-prefix>2001:db8:1:1::/64</pool-prefix>
<start-address>2001:db8:1:1::1000</start-address>
<end-address>2001:db8:1:1::2000</end-address>
<max-address-utilization>50</max-address-utilization>
<option-set-id>1</option-set-id>
<host-reservations>
<host-reservation>
<reserved-addr>2001:db8:1:1::1001</reserved-addr>
<client-duid>00052001db81</client-duid>
<option-set-id>1</option-set-id>
<valid-lifetime>604800</valid-lifetime>
<renew-time>86400</renew-time>
<rebind-time>172800</rebind-time>
<preferred-lifetime>345600</preferred-lifetime>
</host-reservation>
</host-reservations>
</address-pool>
</address-pools>
Figure 5: Server Host Reservation Configuration Example XML Snippet
The following example configuration snippet shows a network range and
pool to be used for delegating prefixes to clients. In this example,
each client will receive a /56 prefix.
The 'max-pd-space-utilization' is set to 80 so that a 'prefix-pool-
utilization-threshold-exceeded' notification will be raised if the
number of prefix allocations exceeds this.
Farrer Expires 22 May 2022 [Page 81]
Internet-Draft DHCPv6 YANG Model November 2021
<allocation-ranges>
<allocation-range>
<id>1</id>
<description>prefix-pool-example</description>
<network-prefix>2001:db8::/32</network-prefix>
<prefix-pools>
<valid-lifetime>54000</valid-lifetime>
<renew-time>7200</renew-time>
<rebind-time>32400</rebind-time>
<preferred-lifetime>43200</preferred-lifetime>
<prefix-pool>
<pool-id>0</pool-id>
<option-set-id>1</option-set-id>
<pool-prefix>2001:db8:1::/48</pool-prefix>
<client-prefix-length>56</client-prefix-length>
<max-pd-space-utilization>80</max-pd-space-utilization>
</prefix-pool>
</prefix-pools>
</allocation-range>
</allocation-ranges>
Figure 6: Server Prefix Delegation Configuration Example XML Snippet
The next example configuration snippet shows a set of options that
may be returned to clients, depending on the contents of a received
DHCP request message. The option set ID is '1', which will
referenced by other places in the configuration (e.g., address pool
configuration) as the available options for clients that request
them.
The example shows how the option definitions can be extended via
augmentation. In this case, "OPTION_SIP_SERVER_D (21) SIP Servers
Domain-Name List" from the example module in Appendix B has been
augmented to the server's option set.
Farrer Expires 22 May 2022 [Page 82]
Internet-Draft DHCPv6 YANG Model November 2021
<option-sets>
<option-set>
<option-set-id>1</option-set-id>
<description>Example DHCP option set</description>
<vendor-specific-information-options>
<vendor-specific-information-option>
<enterprise-number>32473</enterprise-number>
<vendor-option-data>
<sub-option-code>01</sub-option-code>
<sub-option-data>1234abcd</sub-option-data>
</vendor-option-data>
<vendor-option-data>
<sub-option-code>02</sub-option-code>
<sub-option-data>abcd1234</sub-option-data>
</vendor-option-data>
</vendor-specific-information-option>
</vendor-specific-information-options>
<sol-max-rt-option>
<sol-max-rt-value>3600</sol-max-rt-value>
</sol-max-rt-option>
<sip-server-domain-name-list-option
xmlns="https://example.com/ns/example-dhcpv6-opt-sip-serv">
<sip-server>
<sip-serv-id>0</sip-serv-id>
<sip-serv-domain-name>sip1.example.org</sip-serv-domain-name>
</sip-server>
<sip-server>
<sip-serv-id>1</sip-serv-id>
<sip-serv-domain-name>sip2.example.org</sip-serv-domain-name>
</sip-server>
</sip-server-domain-name-list-option>
</option-set>
</option-sets>
Figure 7: Server Option Set Configuration Example XML Snippet
A.2. DHCPv6 Relay Configuration Example
The following example shows a basic configuration for a single DHCP
relay interface and its interaction with the ietf-interfaces module.
The configuration shows two XML documents, one for ietf-interfaces
and a second for ietf-dhcpv6-relay, defining:
* Configuring an interface using the ietf-interfaces module that the
relay configuration will be applied to.
* Enabling the DHCP relay function globally and for the relevant
interface.
Farrer Expires 22 May 2022 [Page 83]
Internet-Draft DHCPv6 YANG Model November 2021
* Referencing the interface that the relay configuration is relevant
for via an inteface-ref to the ietf-interfaces module.
* Defining two destination addresses that incoming DHCP messages
will be relayed to.
* Configures the link-address value that will be sent in the relay-
forward message.
* Configuring a value for the Interface ID Option
(OPTION_INTERFACE_ID (18)), which will be included in the relay
forward message.
<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>
<description>DHCPv6 Relay Interface</description>
<enabled>true</enabled>
</interface>
</interfaces>
<dhcpv6-relay xmlns="urn:ietf:params:xml:ns:yang:ietf-dhcpv6-relay">
<enabled>true</enabled>
<relay-if>
<if-name>eth0</if-name>
<enabled>true</enabled>
<destination-address>2001:db8:2::1</destination-address>
<destination-address>2001:db8:2::2</destination-address>
<link-address>2001:db8:3::1</link-address>
<relay-options>
<interface-id-option>
<interface-id>EXAMPLE-INTERFACE-ID</interface-id>
</interface-id-option>
</relay-options>
</relay-if>
</dhcpv6-relay>
Figure 8: Basic Relay Configuration Example XML
A.3. DHCPv6 Client Configuration Example
The following example shows a basic configuration for a DHCP client
and its interaction with the ietf-interfaces module. The
configuration shows two XML documents, one for ietf-interfaces and a
second for ietf-dhcpv6-client defining:
Farrer Expires 22 May 2022 [Page 84]
Internet-Draft DHCPv6 YANG Model November 2021
* Configuring an interface using the ietf-interfaces module that the
client configuration will be applied to.
* Enabling the DHCP relay function globally and for the relevant
interface.
* References the interface that the client configuration is relevant
for via an inteface-ref to the ietf-interfaces module.
* Sets the client's DUID.
* Configures a list of option codes that will be requested by the
client in its Option Request Option (OPTION_ORO (5)).
* Configures a single instance of the Vendor-specific Information
Option (OPTION_VENDOR_OPTS (17)) with a single sub-option data
item.
* Requests a non-temporary IPv6 address (IA_NA) with an identity
association interface identifier of 1.
* Requests an IPv6 delegated prefix address (IA_PD) with an identity
association interface identifier of 2.
Farrer Expires 22 May 2022 [Page 85]
Internet-Draft DHCPv6 YANG Model November 2021
<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>
<description>DHCPv6 Relay Interface</description>
<enabled>true</enabled>
</interface>
</interfaces>
<dhcpv6-client
xmlns="urn:ietf:params:xml:ns:yang:ietf-dhcpv6-client">
<enabled>true</enabled>
<client-duid>000200090CC084D303000913</client-duid>
<client-if>
<if-name>eth0</if-name>
<enabled>true</enabled>
<client-configured-options>
<option-request-option>
<oro-option>17</oro-option>
<oro-option>23</oro-option>
<oro-option>24</oro-option>
<oro-option>82</oro-option>
</option-request-option>
<vendor-specific-information-options>
<vendor-specific-information-option>
<enterprise-number>32473</enterprise-number>
<vendor-option-data>
<sub-option-code>1</sub-option-code>
<sub-option-data>abcd1234</sub-option-data>
</vendor-option-data>
</vendor-specific-information-option>
</vendor-specific-information-options>
</client-configured-options>
<ia-na>
<ia-id>1</ia-id>
</ia-na>
<ia-pd>
<ia-id>2</ia-id>
</ia-pd>
</client-if>
</dhcpv6-client>
Figure 9: Basic Client Configuration Example XML
Farrer Expires 22 May 2022 [Page 86]
Internet-Draft DHCPv6 YANG Model November 2021
Appendix B. Example of Augmenting Additional DHCPv6 Option Definitions
The following section provides a example of how the DHCPv6 option
definitions can be extended to include additional options. It is
expected that additional specification documents will be published
for this in the future.
The example defines YANG models for OPTION_SIP_SERVER_D (21) and
OPTION_SIP_SERVER_D (22) defined in [RFC3319]. Example XML
configuration, showing the interworking with other modules is
provided in Figure 7.
The module is constructed as follows:
* The module is named using a meaningful, shortened version of the
document name in which the DHCP option format is specified.
* A separate grouping is used to define each option.
* The name of the option is taken from the registered IANA name for
the option, with an '-option' suffix added.
* The description field is taken from the relevant option code name
and number.
* The reference section is the number and name of the RFC in which
the DHCPv6 option is defined.
* The remaining fields match the fields in the DHCP option. They
are in the same order as defined in the DHCP option. Where-ever
possible, the format that is defined for the DHCP field should be
matched by the relevant YANG type.
* Fields which can have multiple entries or instances are defined
using list or leaf-list nodes.
Below the groupings for option definitions, augment statements are
used to add the option definitions for use in the relevant DHCP
element's module (server, relay and/or client).
module example-dhcpv6-opt-sip-serv {
yang-version 1.1;
namespace "https://example.com/ns/" +
"example-dhcpv6-opt-sip-serv";
prefix "sip-srv";
import ietf-inet-types {
prefix inet;
Farrer Expires 22 May 2022 [Page 87]
Internet-Draft DHCPv6 YANG Model November 2021
}
import ietf-dhcpv6-server {
prefix dhc6-srv;
}
organization
"IETF DHC (Dynamic Host Configuration) Working Group";
contact
"WG Web: <https://datatracker.ietf.org/wg/dhc/>
WG List: <mailto:dhcwg@ietf.org>
Author: Yong Cui <yong@csnet1.cs.tsinghua.edu.cn>
Author: Linhui Sun <lh.sunlinh@gmail.com>
Editor: Ian Farrer <ian.farrer@telekom.de>
Author: Sladjana Zeichlin <sladjana.zechlin@telekom.de>
Author: Zihao He <hezihao9512@gmail.com>
Author: Michal Nowikowski <godfryd@isc.org>";
description
"This YANG module contains DHCPv6 options defined in RFC 8415
that can be used by DHCPv6 servers.
Copyright (c) 2021 IETF Trust and the persons identified as
authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject
to the license terms contained in, the Simplified BSD License
set forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see
the RFC itself for full legal notices.";
revision 2021-10-25 {
description
"Initial Revision.";
reference
"XXXX: YANG Data Model for DHCPv6 Configuration";
}
/*
* Groupings
*/
grouping sip-server-domain-name-list-option-group {
Farrer Expires 22 May 2022 [Page 88]
Internet-Draft DHCPv6 YANG Model November 2021
description
"OPTION_SIP_SERVER_D (21) SIP Servers Domain-Name List";
reference "RFC 3319: Dynamic Host Configuration Protocol
(DHCPv6) Options for Session Initiation Protocol (SIP)
Servers";
container sip-server-domain-name-list-option {
description
"OPTION_SIP_SERVER_D (21) SIP Servers Domain Name List
container.";
list sip-server {
key sip-serv-id;
description
"SIP server information.";
leaf sip-serv-id {
type uint8;
description
"SIP server list identifier identifier.";
}
leaf sip-serv-domain-name {
type inet:domain-name;
description
"SIP server domain name.";
}
}
}
}
grouping sip-server-address-list-option-group {
description
"OPTION_SIP_SERVER_A (22) SIP Servers IPv6 Address List";
reference "RFC 3319: Dynamic Host Configuration Protocol
(DHCPv6) Options for Session Initiation Protocol (SIP)
Servers";
container sip-server-address-list-option {
description
"OPTION_SIP_SERVER_A (22) SIP Servers IPv6 Address List
container.";
list sip-server {
key sip-serv-id;
description
"SIP server information.";
leaf sip-serv-id {
type uint8;
description
"SIP server list entry identifier.";
}
leaf sip-serv-addr {
type inet:ipv6-address;
Farrer Expires 22 May 2022 [Page 89]
Internet-Draft DHCPv6 YANG Model November 2021
description
"SIP server IPv6 address.";
}
}
}
}
/*
* Augmentations
*/
augment "/dhc6-srv:dhcpv6-server/dhc6-srv:option-sets/" +
"dhc6-srv:option-set" {
description
"Augment the option definition groupings to the server
module.";
uses sip-server-domain-name-list-option-group;
uses sip-server-address-list-option-group;
}
}
The correct location to augment the new option definition(s) will
vary according to the specific rules defined for the use of that
specific option. For example, for options which will be augmented
into the ietf-dhcpv6-server module, in many cases, these will be
augmented to:
'/dhc6-srv:dhc6-srv/dhc6-srv:option-sets/dhc6-srv:option-set'
So that they can be defined within option sets. However, there are
some options which are only applicable for specific deployment
scenarios and in these cases it may be more logical to augment the
option group to a location relevant for the option.
One example for this could be OPTION_PD_EXCLUDE (67). This option is
only relevant in combination with a delegated prefix which contains a
specific prefix. In this case, the following location for the
augmentation may be more suitable:
'/dhc6-srv:dhc6-srv/dhc6-srv:allocation-ranges/dhc6-srv:allocation-
range/dhc6-srv:prefix-pools/dhc6-srv:prefix-pool"
Appendix C. Example Vendor Specific Server Configuration Module
This section shows how to extend the server YANG module defined in
this document with vendor specific configuration nodes, e.g.,
configuring access to a lease storage database.
Farrer Expires 22 May 2022 [Page 90]
Internet-Draft DHCPv6 YANG Model November 2021
The example module defines additional server attributes such as name
and description. Storage for leases is configured using a lease-
storage container. It allows storing leases in one of three options:
memory (memfile), MySQL and PosgreSQL. For each case, the necessary
configuration parameters are provided.
At the end there is an augment statement which adds the vendor
specific configuration defined in "dhcpv6-server-config:config" under
the "/dhcpv6-server:config/dhcpv6-server:vendor-config" mount point.
module example-dhcpv6-server-conf {
yang-version 1.1;
namespace "https://example.com/ns/" +
"example-dhcpv6-server-conf";
prefix "dhc6-srv-conf";
import ietf-inet-types {
prefix inet;
}
import ietf-interfaces {
prefix if;
}
import ietf-dhcpv6-server {
prefix dhc6-srv;
}
organization
"IETF DHC (Dynamic Host Configuration) Working Group";
contact
"WG Web: <https://datatracker.ietf.org/wg/dhc/>
WG List: <mailto:dhcwg@ietf.org>
Author: Yong Cui <yong@csnet1.cs.tsinghua.edu.cn>
Author: Linhui Sun <lh.sunlinh@gmail.com>
Editor: Ian Farrer <ian.farrer@telekom.de>
Author: Sladjana Zeichlin <sladjana.zechlin@telekom.de>
Author: Zihao He <hezihao9512@gmail.com>
Author: Michal Nowikowski <godfryd@isc.org>";
description
"This YANG module defines components for the configuration and
management of vendor/implementation specific DHCPv6 server
functionality. As this functionality varies greatly between
different implementations, the module is provided as an example
only.
Farrer Expires 22 May 2022 [Page 91]
Internet-Draft DHCPv6 YANG Model November 2021
Copyright (c) 2021 IETF Trust and the persons identified as
authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject
to the license terms contained in, the Simplified BSD License
set forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see
the RFC itself for full legal notices.";
revision 2021-10-25 {
description
"Initial Revision.";
reference
"XXXX: YANG Data Model for DHCPv6 Configuration";
}
/*
* Groupings
*/
grouping config {
description
"Parameters necessary for the configuration of a DHCPv6
server";
container serv-attributes {
description
"Contains basic attributes necessary for running a DHCPv6
server.";
leaf name {
type string;
description
"Name of the DHCPv6 server.";
}
leaf description {
type string;
description
"Description of the DHCPv6 server.";
}
leaf ipv6-listen-port {
type uint16;
default 547;
description
"UDP port that the server will listen on.";
}
Farrer Expires 22 May 2022 [Page 92]
Internet-Draft DHCPv6 YANG Model November 2021
choice listening-interfaces {
default all-interfaces;
description
"Configures which interface or addresses the server will
listen for incoming messages on.";
case all-interfaces {
container all-interfaces {
presence true;
description
"Configures the server to listen for incoming messages
on all IPv6 addresses (unicast and multicast) on all of
its network interfaces.";
}
}
case interface-list {
leaf-list interfaces {
type if:interface-ref;
description
"List of interfaces on which the server will listen for
incoming messages. Messages addressed to any
valid IPv6 address (unicast and multicast) will be
received.";
}
}
case address-list {
leaf-list address-list {
type inet:ipv6-address;
description
"List of IPv6 address(es) on which the server will
listen for incoming DHCPv6 messages.";
}
}
}
leaf-list interfaces-config {
type if:interface-ref;
default "if:interfaces/if:interface/if:name";
description
"A leaf list of interfaces on which the server should
listen.";
}
container lease-storage {
description
"Configures how the server will stores leases.";
choice storage-type {
description
"The type storage that will be used for lease
information.";
Farrer Expires 22 May 2022 [Page 93]
Internet-Draft DHCPv6 YANG Model November 2021
case memfile {
description
"Configuration for storing leases information in a
Comma-Separated Value (CSV) file.";
leaf memfile-name {
type string;
description
"Specifies the absolute location of the lease file.
The format of the string follow the semantics of
the relevant operating system.";
}
leaf memfile-lfc-interval {
type uint64;
description
"Specifies the interval in seconds, at which the
server will perform a lease file cleanup (LFC).";
}
}
case mysql {
leaf mysql-name {
type string;
description
"Name of the database.";
}
choice mysql-host {
description
"Define host or address for MySQL server.";
case mysql-server-hostname {
leaf mysql-hostname {
type inet:domain-name;
default "localhost";
description
"If the database is located on a different
system to the DHCPv6 server, the domain name can
be specified.";
}
}
case mysql-server-address {
leaf mysql-address {
type inet:ip-address;
default "::";
description
"Configure the location of the database using
an IP (v6 or v6) literal address";
}
}
}
leaf mysql-username {
Farrer Expires 22 May 2022 [Page 94]
Internet-Draft DHCPv6 YANG Model November 2021
type string;
description
"User name of the account under which the server
will access the database.";
}
leaf mysql-password {
type string;
description
"Password of the account under which the server
will access the database.";
}
leaf mysql-port {
type inet:port-number;
default 5432;
description
"If the database is located on a different system,
the port number may be specified.";
}
leaf mysql-lfc-interval {
type uint64;
description
"Specifies the interval in seconds, at which the
server will perform a lease file cleanup (LFC).";
}
leaf mysql-connect-timeout {
type uint64;
description
"Defines the timeout interval for connecting to the
database. A longer interval can be specified if the
database is remote.";
}
}
case postgresql {
choice postgresql-host {
description
"Define host or address for postgresql server.";
case postgresql-server-hostname {
leaf postgresql-hostname {
type inet:domain-name;
default "localhost";
description
"If the database is located on a different system
to the DHCPv6 server, the domain name can be
specified.";
}
}
case postgresql-server-address {
Farrer Expires 22 May 2022 [Page 95]
Internet-Draft DHCPv6 YANG Model November 2021
leaf postgresql-address {
type inet:ip-address;
default "::";
description
"Configure the location of the database using
an IP (v6 or v6) literal address";
}
}
}
leaf postgresql-username {
type string;
description
"User name of the account under which the server
will access the database";
}
leaf postgresql-password {
type string;
description
"Password of the account under which the server
will access the database";
}
leaf postgresql-port {
type inet:port-number;
default 5432;
description
"If the database is located on a different system,
the port number may be specified";
}
leaf postgresql-lfc-interval {
type uint64;
description
"Specifies the interval in seconds, at which the
server will perform a lease file cleanup (LFC)";
}
leaf postgresql-connect-timeout {
type uint64;
description
"Defines the timeout interval for connecting to the
database. A longer interval can be specified if the
database is remote.";
}
}
}
}
}
}
/*
Farrer Expires 22 May 2022 [Page 96]
Internet-Draft DHCPv6 YANG Model November 2021
* Augmentations
*/
augment "/dhc6-srv:dhcpv6-server/dhc6-srv:vendor-config" {
description
"Augment the server specific YANG to the ietf-dhcpv6-server
module.";
uses config;
}
}
Appendix D. Example definition of class-selector configuration
The module "ietf-example-dhcpv6-class-selector" provides an example
of how vendor-specific class selection configuration can be modelled
and integrated with the "ietf-dhcpv6-server" module defined in this
document.
The example module defines "client-class-names" with associated
matching rules. A client can be classified based on "client-id",
"interface-id" (ingress interface of the client's messages), packet's
source or destination address, relay link address, relay link
interface-id and more. Actually, there are endless methods for
classifying clients. So this standard does not try to provide full
specification for class selection, it only shows an example how it
could be defined.
At the end of the example augment statements are used to add the
defined class selector rules into the overall DHCPv6 addressing
hierarchy. This is done in two main parts:
* The augmented class-selector configuration in the main DHCPv6
Server configuration.
* client-class leafrefs augmented to "allocation-range", "address-
pool" and "pd-pool", pointing to the "client-class-name" that is
required.
The mechanism is as follows: class is associated to client based on
rules and then client is allowed to get address(es)/prefix(es) from
given allocation-range/pool if the class name matches.
module example-dhcpv6-class-select {
yang-version 1.1;
namespace "https://example.com/ns/" +
"example-dhcpv6-class-select";
prefix "dhc6-class-sel";
Farrer Expires 22 May 2022 [Page 97]
Internet-Draft DHCPv6 YANG Model November 2021
import ietf-inet-types {
prefix inet;
}
import ietf-interfaces {
prefix if;
}
import ietf-dhcpv6-common {
prefix dhc6;
}
import ietf-dhcpv6-server {
prefix dhc6-srv;
}
organization
"IETF DHC (Dynamic Host Configuration) Working Group";
contact
"WG Web: <https://datatracker.ietf.org/wg/dhc/>
WG List: <mailto:dhcwg@ietf.org>
Author: Yong Cui <yong@csnet1.cs.tsinghua.edu.cn>
Author: Linhui Sun <lh.sunlinh@gmail.com>
Editor: Ian Farrer <ian.farrer@telekom.de>
Author: Sladjana Zeichlin <sladjana.zechlin@telekom.de>
Author: Zihao He <hezihao9512@gmail.com>
Author: Michal Nowikowski <godfryd@isc.org>";
description
"This YANG module defines components for the definition and
configuration of the client class selector function for a
DHCPv6 server. As this functionality varies greatly between
different implementations, the module provided as an example
only.
Copyright (c) 2021 IETF Trust and the persons identified as
authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject
to the license terms contained in, the Simplified BSD License
set forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see
the RFC itself for full legal notices.";
Farrer Expires 22 May 2022 [Page 98]
Internet-Draft DHCPv6 YANG Model November 2021
revision 2021-10-25 {
description
"Initial Revision.";
reference
"XXXX: YANG Data Model for DHCPv6 Configuration";
}
/*
* Groupings
*/
grouping client-class-id {
description
"Definitions of client message classification for
authorization and assignment purposes.";
leaf client-class-name {
type string;
description
"Unique Identifier for client class identification list
entries.";
}
choice id-type {
mandatory true;
description
"Definitions for different client identifier types.";
case client-id-id {
leaf client-id {
type string;
mandatory true;
description
"String literal client identifier.";
}
description
"Client class selection based on a string literal client
identifier.";
}
case received-interface-id {
description
"Client class selection based on the incoming interface
of the DHCPv6 message.";
leaf received-interface {
type if:interface-ref;
description
"Reference to the interface entry for the incoming
DHCPv6 message.";
}
}
case packet-source-address-id {
Farrer Expires 22 May 2022 [Page 99]
Internet-Draft DHCPv6 YANG Model November 2021
description
"Client class selection based on the source address of
the DHCPv6 message.";
leaf packet-source-address {
type inet:ipv6-address;
mandatory true;
description
"Source address of the DHCPv6 message.";
}
}
case packet-destination-address-id {
description
"Client class selection based on the destination address
of the DHCPv6 message.";
leaf packet-destination-address {
type inet:ipv6-address;
mandatory true;
description
"Destination address of the DHCPv6 message.";
}
}
case relay-link-address-id {
description
"Client class selection based on the prefix of the
link-address field in the relay agent message header.";
leaf relay-link-address {
type inet:ipv6-prefix;
mandatory true;
description
"Prefix of the link-address field in the relay agent
message header.";
}
}
case relay-peer-address-id {
description
"Client class selection based on the value of the
peer-address field in the relay agent message header.";
leaf relay-peer-address {
type inet:ipv6-prefix;
mandatory true;
description
"Prefix of the peer-address field in the relay agent
message header.";
}
}
case relay-interface-id {
description
"Client class selection based on the incoming
Farrer Expires 22 May 2022 [Page 100]
Internet-Draft DHCPv6 YANG Model November 2021
interface-id option.";
leaf relay-interface {
type string;
description
"Reference to the interface entry for the incoming
DHCPv6 message.";
}
}
case user-class-option-id {
description
"Client class selection based on the value of the
OPTION_USER_CLASS(15) and its user-class-data field.";
leaf user-class-data {
type string;
mandatory true;
description
"Value of the enterprise-number field.";
}
}
case vendor-class-present-id {
description
"Client class selection based on the presence of
OPTION_VENDOR_CLASS(16) in the received message.";
leaf vendor-class-present {
type boolean;
mandatory true;
description
"Presence of OPTION_VENDOR_CLASS(16) in the received
message.";
}
}
case vendor-class-option-enterprise-number-id {
description
"Client class selection based on the value of the
enterprise-number field in OPTION_VENDOR_CLASS(16).";
leaf vendor-class-option-enterprise-number {
type uint32;
mandatory true;
description
"Value of the enterprise-number field.";
}
}
case vendor-class-option-data-id {
description
"Client class selection based on the value of a data
field within a vendor-class-data entry for a matching
enterprise-number field in OPTION_VENDOR_CLASS(16).";
container vendor-class-option-data {
Farrer Expires 22 May 2022 [Page 101]
Internet-Draft DHCPv6 YANG Model November 2021
description
"Vendor class option data container.";
leaf vendor-class-option-enterprise-number {
type uint32;
mandatory true;
description
"Value of the enterprise-number field for matching
the data contents.";
}
leaf vendor-class-data {
type string;
mandatory true;
description
"Vendor class data to match.";
}
}
}
case remote-id {
description
"Client class selection based on the value of Remote-ID.";
container remote-id {
description
"Remote-id client class selector container.";
leaf vendor-class-option-enterprise-number {
type uint32;
mandatory true;
description
"Value of the enterprise-number field for matching the
data contents.";
}
leaf remote-id {
type string;
mandatory true;
description
"Remote-ID data to match.";
}
}
}
case client-duid-id {
description
"Client class selection based on the value of the
received client DUID.";
leaf duid {
type dhc6:duid;
description
"Client DUID.";
}
}
Farrer Expires 22 May 2022 [Page 102]
Internet-Draft DHCPv6 YANG Model November 2021
}
}
/*
* Augmentations
*/
augment "/dhc6-srv:dhcpv6-server/dhc6-srv:class-selector" {
description
"Augment class selector functions to the DHCPv6 server
module.";
container client-classes {
description
"Client classes to augment.";
list class {
key client-class-name;
description
"List of the client class identifiers applicable to
clients served by this address pool";
uses client-class-id;
}
}
}
augment "/dhc6-srv:dhcpv6-server/" +
"dhc6-srv:allocation-ranges/dhc6-srv:allocation-range" {
description
"Augment class selector functions to the DHCPv6 server
allocation-ranges.";
leaf-list client-class {
type leafref {
path "/dhc6-srv:dhcpv6-server/dhc6-srv:" +
"class-selector/client-classes/class/client-class-name";
}
description
"Leafrefs to client classes.";
}
}
augment "/dhc6-srv:dhcpv6-server/dhc6-srv:" +
"allocation-ranges/dhc6-srv:allocation-range/dhc6-srv:" +
"address-pools/dhc6-srv:address-pool" {
description
"Augment class selector functions to the DHCPv6 server
address-pools.";
leaf-list client-class {
type leafref {
path "/dhc6-srv:dhcpv6-server/dhc6-srv:" +
Farrer Expires 22 May 2022 [Page 103]
Internet-Draft DHCPv6 YANG Model November 2021
"class-selector/client-classes/class/client-class-name";
}
description
"Leafrefs to client classes.";
}
}
augment "/dhc6-srv:dhcpv6-server/dhc6-srv:" +
"allocation-ranges/dhc6-srv:allocation-range/dhc6-srv:" +
"prefix-pools/dhc6-srv:prefix-pool" {
description
"Augment class selector functions to the DHCPv6
server prefix-pools.";
leaf-list client-class {
type leafref {
path "/dhc6-srv:dhcpv6-server/dhc6-srv:" +
"class-selector/client-classes/class/client-class-name";
}
description
"Leafrefs to client classes.";
}
}
}
Author's Address
Ian Farrer (editor)
Deutsche Telekom AG
TAI, Landgrabenweg 151
53227 Bonn
Germany
Email: ian.farrer@telekom.de
Farrer Expires 22 May 2022 [Page 104]
