RADIUS Extensions for DHCP-Configured Services
RFC 9445
| Document | Type |
RFC
- Proposed Standard
(August 2023)
Updates RFC 4014
|
|
|---|---|---|---|
| Authors | Mohamed Boucadair , Tirumaleswar Reddy.K , Alan DeKok | ||
| Last updated | 2023-08-16 | ||
| RFC stream | Internet Engineering Task Force (IETF) | ||
| Formats | |||
| Additional resources | Mailing list discussion | ||
| IESG | Responsible AD | Robert Wilton | |
| Send notices to | (None) |
RFC 9445
Internet Engineering Task Force (IETF) M. Boucadair
Request for Comments: 9445 Orange
Updates: 4014 T. Reddy.K
Category: Standards Track Nokia
ISSN: 2070-1721 A. DeKok
FreeRADIUS
August 2023
RADIUS Extensions for DHCP-Configured Services
Abstract
This document specifies two new Remote Authentication Dial-In User
Service (RADIUS) attributes that carry DHCP options. The
specification is generic and can be applicable to any service that
relies upon DHCP. Both DHCPv4- and DHCPv6-configured services are
covered.
Also, this document updates RFC 4014 by relaxing a constraint on
permitted RADIUS attributes in the RADIUS Attributes DHCP suboption.
Status of This Memo
This is an Internet Standards Track document.
This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 7841.
Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
https://www.rfc-editor.org/info/rfc9445.
Copyright Notice
Copyright (c) 2023 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 Revised BSD License text as described in Section 4.e of the
Trust Legal Provisions and are provided without warranty as described
in the Revised BSD License.
Table of Contents
1. Introduction
2. Terminology
3. RADIUS DHCP Options Attributes
3.1. DHCPv6-Options Attribute
3.2. DHCPv4-Options Attribute
4. Passing RADIUS DHCP Options Attributes by DHCP Relay Agents to
DHCP Servers
4.1. Context
4.2. Updates to RFC 4014
4.2.1. Section 3 of RFC 4014
4.2.2. Section 4 of RFC 4014
5. An Example: Applicability to Encrypted DNS Provisioning
6. Security Considerations
7. Table of Attributes
8. IANA Considerations
8.1. New RADIUS Attributes
8.2. New RADIUS Attribute Permitted in DHCPv6 RADIUS Option
8.3. RADIUS Attributes Permitted in RADIUS Attributes DHCP
Suboption
8.4. DHCP Options Permitted in the RADIUS DHCP*-Options
Attributes
8.4.1. DHCPv6
8.4.2. DHCPv4
8.4.3. Guidelines for the Designated Experts
9. References
9.1. Normative References
9.2. Informative References
Acknowledgements
Authors' Addresses
1. Introduction
In the context of broadband services, Internet Service Providers
(ISPs) usually provide DNS resolvers to their customers. To that
aim, ISPs deploy dedicated mechanisms (e.g., DHCP [RFC2132] [RFC8415]
and IPv6 Router Advertisement [RFC4861]) to advertise a list of DNS
recursive servers to their customers. Typically, the information
used to populate DHCP messages and/or IPv6 Router Advertisements
relies upon specific Remote Authentication Dial-In User Service
(RADIUS) [RFC2865] attributes, such as the DNS-Server-IPv6-Address
Attribute specified in [RFC6911].
With the advent of encrypted DNS (e.g., DNS over HTTPS (DoH)
[RFC8484], DNS over TLS (DoT) [RFC7858], or DNS over QUIC (DoQ)
[RFC9250]), additional means are required to provision hosts with
network-designated encrypted DNS. To fill that void, [DNR] leverages
existing protocols such as DHCP to provide hosts with the required
information to connect to an encrypted DNS resolver. However, there
are no RADIUS attributes that can be used to populate the discovery
messages discussed in [DNR]. The same concern is likely to be
encountered for future services that are configured using DHCP.
This document specifies two new RADIUS attributes: DHCPv6-Options
(Section 3.1) and DHCPv4-Options (Section 3.2). These attributes can
include DHCP options that are listed in the "DHCPv6 Options Permitted
in the RADIUS DHCPv6-Options Attribute" registry (Section 8.4.1) and
the "DHCP Options Permitted in the RADIUS DHCPv4-Options Attribute"
registry (Section 8.4.2). These two attributes are specified in
order to accommodate both IPv4 and IPv6 deployment contexts while
taking into account the constraints in Section 3.4 of [RFC6158].
The mechanism specified in this document is a generic mechanism and
might be employed in network scenarios where the DHCP server and the
RADIUS client are located in the same device. The new attributes can
also be used in deployments that rely upon the mechanisms defined in
[RFC4014] or [RFC7037], which allow a DHCP relay agent that is
collocated with a RADIUS client to pass attributes obtained from a
RADIUS server to a DHCP server. However, an update to [RFC4014] is
required so that a DHCP relay agent can pass the DHCPv4-Options
Attribute obtained from a RADIUS server to a DHCP server (Section 4).
DHCP options that are included in the new RADIUS attributes can be
controlled by a deployment-specific policy. Discussing such a policy
is out of scope.
This document adheres to [RFC8044] for defining the new attributes.
A sample deployment usage of the RADIUS DHCPv6-Options and
DHCPv4-Options Attributes is described in Section 5.
2. Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in
BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
This document makes use of the terms defined in [RFC2865], [RFC8415],
and [RFC8499]. The following additional terms are used:
DHCP: refers to both DHCPv4 [RFC2132] and DHCPv6 [RFC8415].
Encrypted DNS: refers to a scheme where DNS exchanges are
transported over an encrypted channel. Examples of encrypted DNS
are DoT, DoH, and DoQ.
Encrypted DNS resolver: refers to a resolver (Section 6 of
[RFC8499]) that supports encrypted DNS.
DHCP*-Options: refers to the DHCPv4-Options and DHCPv6-Options
Attributes (Section 3).
3. RADIUS DHCP Options Attributes
This section specifies two new RADIUS attributes for RADIUS clients
and servers to exchange DHCP-encoded data. This data is then used to
feed the DHCP procedure between a DHCP client and a DHCP server.
Both the DHCPv4-Options and DHCPv6-Options Attributes use the "Long
Extended Type" format (Section 2.2 of [RFC6929]). The description of
the fields is provided in Sections 3.1 and 3.2.
These attributes use the "Long Extended Type" format in order to
permit the transport of attributes encapsulating more than 253 octets
of data. DHCP options that can be included in the RADIUS DHCP*-
Options Attributes are limited by the maximum packet size of 4096
bytes (Section 3 of [RFC2865]). In order to accommodate deployments
with large DHCP options, RADIUS implementations are RECOMMENDED to
support a packet size up to 65535 bytes. Such a recommendation can
be met if RADIUS implementations support a mechanism that relaxes the
limit of 4096 bytes (e.g., the mechanisms described in [RFC7499] or
[RFC7930]).
The Value fields of the DHCP*-Options Attributes are encoded in the
clear and not encrypted like, for example, the Tunnel-Password
Attribute [RFC2868].
RADIUS implementations may support a configuration parameter to
control the DHCP options that can be included in a RADIUS DHCP*-
Options Attribute. Likewise, DHCP server implementations may support
a configuration parameter to control the permitted DHCP options in a
RADIUS DHCP*-Options Attribute. Absent explicit configuration,
RADIUS implementations and DHCP server implementations SHOULD ignore
non-permitted DHCP options received in a RADIUS DHCP*-Options
Attribute.
RADIUS-supplied data is specific configuration data that is returned
as a function of authentication and authorization checks. As such,
absent any explicit configuration on the DHCP server, RADIUS-supplied
data by means of the DHCP*-Options Attributes take precedence over
any local configuration.
These attributes are defined with globally unique names. The naming
of the attributes follows the guidelines in Section 2.7.1 of
[RFC6929]. Invalid attributes are handled as per Section 2.8 of
[RFC6929].
3.1. DHCPv6-Options Attribute
This attribute is of type "string" as defined in Section 3.5 of
[RFC8044].
The DHCPv6-Options Attribute MAY appear in a RADIUS Access-Accept
packet. It MAY also appear in a RADIUS Access-Request packet as a
hint to the RADIUS server to indicate a preference. However, the
server is not required to honor such a preference.
The DHCPv6-Options Attribute MAY appear in a RADIUS CoA-Request
packet.
The DHCPv6-Options Attribute MAY appear in a RADIUS Accounting-
Request packet.
The DHCPv6-Options Attribute MUST NOT appear in any other RADIUS
packet.
The DHCPv6-Options Attribute is structured as follows:
Type
245
Length
This field indicates the total length, in octets, of all fields of
this attribute, including the Type, Length, Extended-Type, and
Value fields.
Extended-Type
3 (see Section 8.1)
Value
This field contains a list of DHCPv6 options (Section 21 of
[RFC8415]). Multiple instances of the same DHCPv6 option MAY be
included. If an option appears multiple times, each instance is
considered separate, and the data areas of the options MUST NOT be
concatenated or otherwise combined. Consistent with Section 17 of
[RFC7227], this document does not impose any option order when
multiple options are present.
The permitted DHCPv6 options are listed in the "DHCPv6 Options
Permitted in the RADIUS DHCPv6-Options Attribute" registry
(Section 8.4.1).
The DHCPv6-Options Attribute is associated with the following
identifier: 245.3.
3.2. DHCPv4-Options Attribute
This attribute is of type "string" as defined in Section 3.5 of
[RFC8044].
The DHCPv4-Options Attribute MAY appear in a RADIUS Access-Accept
packet. It MAY also appear in a RADIUS Access-Request packet as a
hint to the RADIUS server to indicate a preference. However, the
server is not required to honor such a preference.
The DHCPv4-Options Attribute MAY appear in a RADIUS CoA-Request
packet.
The DHCPv4-Options Attribute MAY appear in a RADIUS Accounting-
Request packet.
The DHCPv4-Options Attribute MUST NOT appear in any other RADIUS
packet.
The DHCPv4-Options Attribute is structured as follows:
Type
245
Length
This field indicates the total length, in octets, of all fields of
this attribute, including the Type, Length, Extended-Type, and
Value fields.
Extended-Type
4 (see Section 8.1)
Value
This field contains a list of DHCPv4 options. Multiple instances
of the same DHCPv4 option MAY be included, especially for
concatenation-requiring options that exceed the maximum DHCPv4
option size of 255 octets. The mechanism specified in [RFC3396]
MUST be used for splitting and concatenating the instances of a
concatenation-requiring option.
The permitted DHCPv4 options are listed in the "DHCP Options
Permitted in the RADIUS DHCPv4-Options Attribute" registry
(Section 8.4.2).
The DHCPv4-Options Attribute is associated with the following
identifier: 245.4.
4. Passing RADIUS DHCP Options Attributes by DHCP Relay Agents to DHCP
Servers
4.1. Context
The RADIUS Attributes DHCP suboption [RFC4014] enables a DHCPv4 relay
agent to pass identification and authorization attributes received
during RADIUS authentication to a DHCPv4 server. However, [RFC4014]
defines a frozen set of RADIUS attributes that can be included in
such a suboption. This limitation is suboptimal in contexts where
new services are deployed (e.g., support of encrypted DNS [DNR]).
Section 4.2 updates [RFC4014] by relaxing that constraint and
allowing additional RADIUS attributes to be tagged as permitted in
the RADIUS Attributes DHCP suboption. The permitted attributes are
registered in the new "RADIUS Attributes Permitted in RADIUS
Attributes DHCP Suboption" registry (Section 8.3).
4.2. Updates to RFC 4014
4.2.1. Section 3 of RFC 4014
This document updates Section 3 of [RFC4014] as follows:
OLD:
| To avoid dependencies between the address allocation and other
| state information between the RADIUS server and the DHCP server,
| the DHCP relay agent SHOULD include only the attributes in the
| table below in an instance of the RADIUS Attributes suboption.
| The table, based on the analysis in RFC 3580 [8], lists attributes
| that MAY be included:
|
| # Attribute
| --- ---------
| 1 User-Name (RFC 2865 [3])
| 6 Service-Type (RFC 2865)
| 26 Vendor-Specific (RFC 2865)
| 27 Session-Timeout (RFC 2865)
| 88 Framed-Pool (RFC 2869)
| 100 Framed-IPv6-Pool (RFC 3162 [7])
NEW:
| To avoid dependencies between the address allocation and other
| state information between the RADIUS server and the DHCP server,
| the DHCP relay agent SHOULD only include the attributes in the
| "RADIUS Attributes Permitted in RADIUS Attributes DHCP Suboption"
| registry (Section 8.3 of [RFC9445]) in an instance of the RADIUS
| Attributes DHCP suboption. The DHCP relay agent may support a
| configuration parameter to control the attributes in a RADIUS
| Attributes DHCP suboption.
4.2.2. Section 4 of RFC 4014
This document updates Section 4 of [RFC4014] as follows:
OLD:
| If the relay agent relays RADIUS attributes not included in the
| table in Section 4, the DHCP server SHOULD ignore them.
NEW:
| If the relay agent relays RADIUS attributes not included in the
| "RADIUS Attributes Permitted in RADIUS Attributes DHCP Suboption"
| registry (Section 8.3 of [RFC9445]) and explicit configuration is
| absent, the DHCP server SHOULD ignore them.
5. An Example: Applicability to Encrypted DNS Provisioning
Typical deployment scenarios are similar to those described, for
instance, in Section 2 of [RFC6911]. For illustration purposes,
Figure 1 shows an example where a Customer Premises Equipment (CPE)
is provided with an encrypted DNS resolver. This example assumes
that the Network Access Server (NAS) embeds both RADIUS client and
DHCPv6 server capabilities.
+-------------+ +-------------+ +-------+
| CPE | | NAS | | AAA |
|DHCPv6 Client| |DHCPv6 Server| |Server |
| | |RADIUS Client| | |
+------+------+ +------+------+ +---+---+
| | |
o-----DHCPv6 Solicit----->| |
| o----Access-Request ---->|
| | |
| |<----Access-Accept------o
| | DHCPv6-Options |
|<----DHCPv6 Advertise----o (OPTION_V6_DNR) |
| (OPTION_V6_DNR) | |
| | |
o-----DHCPv6 Request----->| |
| | |
|<------DHCPv6 Reply------o |
| (OPTION_V6_DNR) | |
| | |
DHCPv6 RADIUS
Figure 1: An Example of RADIUS IPv6 Encrypted DNS Exchange
Upon receipt of the DHCPv6 Solicit message from a CPE, the NAS sends
a RADIUS Access-Request message to the Authentication, Authorization,
and Accounting (AAA) server. Once the AAA server receives the
request, it replies with an Access-Accept message (possibly after
having sent a RADIUS Access-Challenge message and assuming the CPE is
entitled to connect to the network) that carries a list of parameters
to be used for this session, which includes the encrypted DNS
information. Such information is encoded as OPTION_V6_DNR (144)
instances [DNR] in the RADIUS DHCPv6-Options Attribute. These
instances are then used by the NAS to complete the DHCPv6 procedure
that the CPE initiated to retrieve information about the encrypted
DNS service to use. The Discovery of Network-designated Resolvers
(DNR) procedure defined in [DNR] is then followed between the DHCPv6
client and the DHCPv6 server.
Should any encrypted DNS-related information (e.g., Authentication
Domain Name (ADN) and IPv6 address) change, the RADIUS server sends a
RADIUS Change-of-Authorization (CoA) message [RFC5176] that carries
the DHCPv6-Options Attribute with the updated OPTION_V6_DNR
information to the NAS. Once that message is received and validated
by the NAS, it replies with a RADIUS CoA ACK message. The NAS
replaces the old encrypted DNS resolver information with the new one
and sends a DHCPv6 Reconfigure message, which leads the DHCPv6 client
to initiate a Renew/Reply message exchange with the DHCPv6 server.
In deployments where the NAS behaves as a DHCPv6 relay agent, the
procedure discussed in Section 3 of [RFC7037] can be followed. To
that aim, the "RADIUS Attributes Permitted in DHCPv6 RADIUS Option"
registry has been updated (Section 8.2). CoA-Requests can be used
following the procedure specified in [RFC6977].
Figure 2 shows another example where a CPE is provided with an
encrypted DNS resolver, but the CPE uses DHCPv4 to retrieve its
encrypted DNS resolver.
+-------------+ +-------------+ +-------+
| CPE | | NAS | | AAA |
|DHCPv4 Client| |DHCPv4 Server| |Server |
| | |RADIUS Client| | |
+------+------+ +------+------+ +---+---+
| | |
o------DHCPDISCOVER------>| |
| o----Access-Request ---->|
| | |
| |<----Access-Accept------o
| | DHCPv4-Options |
|<-----DHCPOFFER----------o (OPTION_V4_DNR) |
| (OPTION_V4_DNR) | |
| | |
o-----DHCPREQUEST-------->| |
| (OPTION_V4_DNR) | |
| | |
|<-------DHCPACK----------o |
| (OPTION_V4_DNR) | |
| | |
DHCPv4 RADIUS
Figure 2: An Example of RADIUS IPv4 Encrypted DNS Exchange
Other deployment scenarios can be envisaged, such as returning
customized service parameters (e.g., different DoH URI Templates) as
a function of the service, policies, and preferences that are set by
a network administrator. How an administrator indicates its service,
policies, and preferences to a AAA server is out of scope.
6. Security Considerations
RADIUS-related security considerations are discussed in [RFC2865].
DHCPv6-related security issues are discussed in Section 22 of
[RFC8415], while DHCPv4-related security issues are discussed in
Section 7 of [RFC2131]. Security considerations specific to the DHCP
options that are carried in RADIUS are discussed in relevant
documents that specify these options. For example, security
considerations (including traffic theft) are discussed in Section 7
of [DNR].
RADIUS servers have conventionally tolerated the input of arbitrary
data via the "string" data type (Section 3.5 of [RFC8044]). This
practice allows RADIUS servers to support newer standards without
software upgrades, by allowing administrators to manually create
complex attribute content and then pass that content to a RADIUS
server as opaque strings. While this practice is useful, it is
RECOMMENDED that RADIUS servers that implement the present
specification are updated to understand the format and encoding of
DHCP options. Administrators can thus enter the DHCP options as
options instead of manually encoded opaque strings. This
recommendation increases security and interoperability by ensuring
that the options are encoded correctly. It also increases usability
for administrators.
The considerations discussed in Section 7 of [RFC4014] and Section 8
of [RFC7037] should be taken into account in deployments where DHCP
relay agents pass the DHCP*-Options Attributes to DHCP servers.
Additional considerations specific to the use of Reconfigure messages
are discussed in Section 9 of [RFC6977].
7. Table of Attributes
The following table provides a guide as to what type of RADIUS
packets may contain these attributes and in what quantity.
+=============+=======+=========+===========+=====+================+
| Access- |Access-| Access- | Challenge |# | Attribute |
| Request |Accept | Reject | | | |
+=============+=======+=========+===========+=====+================+
| 0+ |0+ | 0 | 0 |245.3| DHCPv6-Options |
+-------------+-------+---------+-----------+-----+----------------+
| 0+ |0+ | 0 | 0 |245.4| DHCPv4-Options |
+=============+=======+=========+===========+=====+================+
| Accounting- |CoA- | CoA-ACK | CoA-NACK |# | Attribute |
| Request |Request| | | | |
+=============+=======+=========+===========+=====+================+
| 0+ |0+ | 0 | 0 |245.3| DHCPv6-Options |
+-------------+-------+---------+-----------+-----+----------------+
| 0+ |0+ | 0 | 0 |245.4| DHCPv4-Options |
+-------------+-------+---------+-----------+-----+----------------+
Table 1: Table of Attributes
Notation for Table 1:
0 This attribute MUST NOT be present in packet.
0+ Zero or more instances of this attribute MAY be present in
packet.
8. IANA Considerations
8.1. New RADIUS Attributes
IANA has assigned two new RADIUS attribute types in the "Radius
Attribute Types" [RADIUS-Types] registry:
+=======+================+===========+===========+
| Value | Description | Data Type | Reference |
+=======+================+===========+===========+
| 245.3 | DHCPv6-Options | string | RFC 9445 |
+-------+----------------+-----------+-----------+
| 245.4 | DHCPv4-Options | string | RFC 9445 |
+-------+----------------+-----------+-----------+
Table 2: New RADIUS Attributes
8.2. New RADIUS Attribute Permitted in DHCPv6 RADIUS Option
IANA has added the following entry to the "RADIUS Attributes
Permitted in DHCPv6 RADIUS Option" subregistry in the "Dynamic Host
Configuration Protocol for IPv6 (DHCPv6)" registry [DHCPv6]:
+===========+================+===========+
| Type Code | Attribute | Reference |
+===========+================+===========+
| 245.3 | DHCPv6-Options | RFC 9445 |
+-----------+----------------+-----------+
Table 3: New RADIUS Attribute
Permitted in DHCPv6 RADIUS Option
8.3. RADIUS Attributes Permitted in RADIUS Attributes DHCP Suboption
IANA has created a new subregistry entitled "RADIUS Attributes
Permitted in RADIUS Attributes DHCP Suboption" in the "Dynamic Host
Configuration Protocol (DHCP) and Bootstrap Protocol (BOOTP)
Parameters" registry [BOOTP].
The allocation policy of this new subregistry is "Expert Review"
(Section 4.5 of [RFC8126]). Designated experts should carefully
consider the security implications of allowing a relay agent to
include new RADIUS attributes in this subregistry. Additional
considerations are provided in Section 8.4.3.
The initial contents of this subregistry are listed in Table 4. The
Reference field includes the document that registers or specifies the
attribute.
+===========+==================+===========+
| Type Code | Attribute | Reference |
+===========+==================+===========+
| 1 | User-Name | [RFC2865] |
+-----------+------------------+-----------+
| 6 | Service-Type | [RFC2865] |
+-----------+------------------+-----------+
| 26 | Vendor-Specific | [RFC2865] |
+-----------+------------------+-----------+
| 27 | Session-Timeout | [RFC2865] |
+-----------+------------------+-----------+
| 88 | Framed-Pool | [RFC2869] |
+-----------+------------------+-----------+
| 100 | Framed-IPv6-Pool | [RFC3162] |
+-----------+------------------+-----------+
| 245.4 | DHCPv4-Options | RFC 9445 |
+-----------+------------------+-----------+
Table 4: Initial Contents of RADIUS
Attributes Permitted in RADIUS
Attributes DHCP Suboption Registry
8.4. DHCP Options Permitted in the RADIUS DHCP*-Options Attributes
8.4.1. DHCPv6
IANA has created a new subregistry entitled "DHCPv6 Options Permitted
in the RADIUS DHCPv6-Options Attribute" in the "Dynamic Host
Configuration Protocol for IPv6 (DHCPv6)" registry [DHCPv6].
The registration policy for this new subregistry is "Expert Review"
(Section 4.5 of [RFC8126]). See more details in Section 8.4.3.
The initial content of this subregistry is listed in Table 5. The
Value and Description fields echo those in the "Option Codes"
subregistry of [DHCPv6]. The Reference field includes the document
that registers or specifies the option.
+=======+===============+===========+
| Value | Description | Reference |
+=======+===============+===========+
| 144 | OPTION_V6_DNR | RFC 9445 |
+-------+---------------+-----------+
Table 5: Initial Content of
DHCPv6 Options Permitted in the
RADIUS DHCPv6-Options Attribute
Registry
8.4.2. DHCPv4
IANA has created a new subregistry entitled "DHCP Options Permitted
in the RADIUS DHCPv4-Options Attribute" in the "Dynamic Host
Configuration Protocol (DHCP) and Bootstrap Protocol (BOOTP)
Parameters" registry [BOOTP].
The registration policy for this new subregistry is Expert Review
(Section 4.5 of [RFC8126]). See more details in Section 8.4.3.
The initial content of this subregistry is listed in Table 6. The
Tag and Name fields echo those in the "BOOTP Vendor Extensions and
DHCP Options" subregistry of [BOOTP]. The Reference field includes
the document that registers or specifies the option.
+=====+===============+===========+
| Tag | Name | Reference |
+=====+===============+===========+
| 162 | OPTION_V4_DNR | RFC 9445 |
+-----+---------------+-----------+
Table 6: Initial Content of
DHCPv4 Options Permitted in the
RADIUS DHCPv4-Options Attribute
Registry
8.4.3. Guidelines for the Designated Experts
It is suggested that multiple designated experts be appointed for
registry change requests.
Criteria that should be applied by the designated experts include
determining whether the proposed registration duplicates existing
entries and whether the registration description is clear and fits
the purpose of this registry.
Registration requests are to be sent to <radius-dhcp-review@ietf.org>
and are evaluated within a three-week review period on the advice of
one or more designated experts. Within the review period, the
designated experts will either approve or deny the registration
request, communicating this decision to the review list and IANA.
Denials should include an explanation and, if applicable, suggestions
as to how to make the request successful.
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>.
[RFC2865] Rigney, C., Willens, S., Rubens, A., and W. Simpson,
"Remote Authentication Dial In User Service (RADIUS)",
RFC 2865, DOI 10.17487/RFC2865, June 2000,
<https://www.rfc-editor.org/info/rfc2865>.
[RFC3396] Lemon, T. and S. Cheshire, "Encoding Long Options in the
Dynamic Host Configuration Protocol (DHCPv4)", RFC 3396,
DOI 10.17487/RFC3396, November 2002,
<https://www.rfc-editor.org/info/rfc3396>.
[RFC4014] Droms, R. and J. Schnizlein, "Remote Authentication Dial-
In User Service (RADIUS) Attributes Suboption for the
Dynamic Host Configuration Protocol (DHCP) Relay Agent
Information Option", RFC 4014, DOI 10.17487/RFC4014,
February 2005, <https://www.rfc-editor.org/info/rfc4014>.
[RFC6158] DeKok, A., Ed. and G. Weber, "RADIUS Design Guidelines",
BCP 158, RFC 6158, DOI 10.17487/RFC6158, March 2011,
<https://www.rfc-editor.org/info/rfc6158>.
[RFC6929] DeKok, A. and A. Lior, "Remote Authentication Dial In User
Service (RADIUS) Protocol Extensions", RFC 6929,
DOI 10.17487/RFC6929, April 2013,
<https://www.rfc-editor.org/info/rfc6929>.
[RFC8044] DeKok, A., "Data Types in RADIUS", RFC 8044,
DOI 10.17487/RFC8044, January 2017,
<https://www.rfc-editor.org/info/rfc8044>.
[RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for
Writing an IANA Considerations Section in RFCs", BCP 26,
RFC 8126, DOI 10.17487/RFC8126, June 2017,
<https://www.rfc-editor.org/info/rfc8126>.
[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>.
[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>.
9.2. Informative References
[BOOTP] IANA, "Dynamic Host Configuration Protocol (DHCP) and
Bootstrap Protocol (BOOTP) Parameters",
<https://www.iana.org/assignments/bootp-dhcp-parameters>.
[DHCPv6] IANA, "Dynamic Host Configuration Protocol for IPv6
(DHCPv6)",
<https://www.iana.org/assignments/dhcpv6-parameters>.
[DNR] Boucadair, M., Ed., Reddy.K, T., Ed., Wing, D., Cook, N.,
and T. Jensen, "DHCP and Router Advertisement Options for
the Discovery of Network-designated Resolvers (DNR)", Work
in Progress, Internet-Draft, draft-ietf-add-dnr-16, 27
April 2023, <https://datatracker.ietf.org/doc/html/draft-
ietf-add-dnr-16>.
[RADIUS-Types]
IANA, "RADIUS Types",
<http://www.iana.org/assignments/radius-types>.
[RFC2131] Droms, R., "Dynamic Host Configuration Protocol",
RFC 2131, DOI 10.17487/RFC2131, March 1997,
<https://www.rfc-editor.org/info/rfc2131>.
[RFC2132] Alexander, S. and R. Droms, "DHCP Options and BOOTP Vendor
Extensions", RFC 2132, DOI 10.17487/RFC2132, March 1997,
<https://www.rfc-editor.org/info/rfc2132>.
[RFC2868] Zorn, G., Leifer, D., Rubens, A., Shriver, J., Holdrege,
M., and I. Goyret, "RADIUS Attributes for Tunnel Protocol
Support", RFC 2868, DOI 10.17487/RFC2868, June 2000,
<https://www.rfc-editor.org/info/rfc2868>.
[RFC2869] Rigney, C., Willats, W., and P. Calhoun, "RADIUS
Extensions", RFC 2869, DOI 10.17487/RFC2869, June 2000,
<https://www.rfc-editor.org/info/rfc2869>.
[RFC3162] Aboba, B., Zorn, G., and D. Mitton, "RADIUS and IPv6",
RFC 3162, DOI 10.17487/RFC3162, August 2001,
<https://www.rfc-editor.org/info/rfc3162>.
[RFC4861] Narten, T., Nordmark, E., Simpson, W., and H. Soliman,
"Neighbor Discovery for IP version 6 (IPv6)", RFC 4861,
DOI 10.17487/RFC4861, September 2007,
<https://www.rfc-editor.org/info/rfc4861>.
[RFC5176] Chiba, M., Dommety, G., Eklund, M., Mitton, D., and B.
Aboba, "Dynamic Authorization Extensions to Remote
Authentication Dial In User Service (RADIUS)", RFC 5176,
DOI 10.17487/RFC5176, January 2008,
<https://www.rfc-editor.org/info/rfc5176>.
[RFC6911] Dec, W., Ed., Sarikaya, B., Zorn, G., Ed., Miles, D., and
B. Lourdelet, "RADIUS Attributes for IPv6 Access
Networks", RFC 6911, DOI 10.17487/RFC6911, April 2013,
<https://www.rfc-editor.org/info/rfc6911>.
[RFC6977] Boucadair, M. and X. Pougnard, "Triggering DHCPv6
Reconfiguration from Relay Agents", RFC 6977,
DOI 10.17487/RFC6977, July 2013,
<https://www.rfc-editor.org/info/rfc6977>.
[RFC7037] Yeh, L. and M. Boucadair, "RADIUS Option for the DHCPv6
Relay Agent", RFC 7037, DOI 10.17487/RFC7037, October
2013, <https://www.rfc-editor.org/info/rfc7037>.
[RFC7227] Hankins, D., Mrugalski, T., Siodelski, M., Jiang, S., and
S. Krishnan, "Guidelines for Creating New DHCPv6 Options",
BCP 187, RFC 7227, DOI 10.17487/RFC7227, May 2014,
<https://www.rfc-editor.org/info/rfc7227>.
[RFC7499] Perez-Mendez, A., Ed., Marin-Lopez, R., Pereniguez-Garcia,
F., Lopez-Millan, G., Lopez, D., and A. DeKok, "Support of
Fragmentation of RADIUS Packets", RFC 7499,
DOI 10.17487/RFC7499, April 2015,
<https://www.rfc-editor.org/info/rfc7499>.
[RFC7858] Hu, Z., Zhu, L., Heidemann, J., Mankin, A., Wessels, D.,
and P. Hoffman, "Specification for DNS over Transport
Layer Security (TLS)", RFC 7858, DOI 10.17487/RFC7858, May
2016, <https://www.rfc-editor.org/info/rfc7858>.
[RFC7930] Hartman, S., "Larger Packets for RADIUS over TCP",
RFC 7930, DOI 10.17487/RFC7930, August 2016,
<https://www.rfc-editor.org/info/rfc7930>.
[RFC8484] Hoffman, P. and P. McManus, "DNS Queries over HTTPS
(DoH)", RFC 8484, DOI 10.17487/RFC8484, October 2018,
<https://www.rfc-editor.org/info/rfc8484>.
[RFC8499] Hoffman, P., Sullivan, A., and K. Fujiwara, "DNS
Terminology", BCP 219, RFC 8499, DOI 10.17487/RFC8499,
January 2019, <https://www.rfc-editor.org/info/rfc8499>.
[RFC9250] Huitema, C., Dickinson, S., and A. Mankin, "DNS over
Dedicated QUIC Connections", RFC 9250,
DOI 10.17487/RFC9250, May 2022,
<https://www.rfc-editor.org/info/rfc9250>.
Acknowledgements
Thanks to Christian Jacquenet, Neil Cook, Joe Clarke, Qin Wu, Dirk
von-Hugo, Tom Petch, and Chongfeng Xie for the review and
suggestions.
Thanks to Ben Schwartz and Bernie Volz for the comments.
Thanks to Rob Wilton for the careful AD review.
Thanks to Ralf Weber for the dnsdir reviews, Robert Sparks for the
genart review, and Tatuya Jinmei for the intdir review.
Thanks to Éric Vyncke, Paul Wouters, and Warren Kumari for the IESG
review.
Authors' Addresses
Mohamed Boucadair
Orange
35000 Rennes
France
Email: mohamed.boucadair@orange.com
Tirumaleswar Reddy.K
Nokia
India
Email: kondtir@gmail.com
Alan DeKok
FreeRADIUS
Email: aland@freeradius.org