wdiff draft-ietf-regext-rdap-openid-09.txt draft-ietf-regext-rdap-openid-10.txt

REGEXT Working Group S. Hollenbeck
Internet-Draft Verisign Labs
Intended status: Standards Track 18 January 8 February 2022
Expires: 22 July 12 August 2022

Federated Authentication for the Registration Data Access Protocol
(RDAP) using OpenID Connect
draft-ietf-regext-rdap-openid-09
draft-ietf-regext-rdap-openid-10

Abstract

The Registration Data Access Protocol (RDAP) provides "RESTful" web
services to retrieve registration metadata from domain name and
regional internet registries. RDAP allows a server to make access
control decisions based on client identity, and as such it includes
support for client identification features provided by the Hypertext
Transfer Protocol (HTTP). Identification methods that require
clients to obtain and manage credentials from every RDAP server
operator present management challenges for both clients and servers,
whereas a federated authentication system would make it easier to
operate and use RDAP without the need to maintain server-specific
client credentials. This document describes a federated
authentication system for RDAP based on OpenID Connect.

Status of This Memo

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This Internet-Draft will expire on 22 July 12 August 2022.

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Table of Contents

1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Problem Statement . . . . . . . . . . . . . . . . . . . . 3
1.2. Proposal . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions Used in This Document . . . . . . . . . . . . . . 4
3. Federated Authentication for RDAP . . . . . . . . . . . . . . 4
3.1. RDAP and OpenID Connect . . . . . . . . . . . . . . . . . 4 5
3.1.1. Terminology . . . . . . . . . . . . . . . . . . . . . 5
3.1.2. Overview . . . . . . . . . . . . . . . . . . . . . . 5
3.1.3. RDAP Authentication and Authorization Steps . . . . . 6
3.1.3.1. Provider Discovery . . . . . . . . . . . . . . . 6
3.1.3.2. Authentication Request . . . . . . . . . . . . . 6 7
3.1.3.3. End-User Authorization . . . . . . . . . . . . . 7
3.1.3.4. Authorization Response and Validation . . . . . . 7 8
3.1.3.5. Token Processing . . . . . . . . . . . . . . . . 7 8
3.1.3.6. Delivery of User Information . . . . . . . . . . 8
3.1.4. Specialized Claims for RDAP . . . . . . . . . . . . . 8
3.1.4.1. Stated Purpose . . . . . . . . . . . . . . . . . 8
3.1.4.2. Do Not Track . . . . . . . . . . . . . . . . . . 9
4. Protocol Parameters . . . . . . . . . . . . . . . . . . . . . 10
4.1. Client Authentication Request and Response Login . . . . . . . 10
4.2. Token Request and Response . . . . . . . . . . . . . . . 11
4.3. Token Refresh and Revocation 10
4.1.1. Clients with Limited User Interfaces . . . . . . . . 13
4.1.1.1. OAuth 2.0 Device Authorization Grant . . . . . . 13
4.4. Token Exchange
4.1.1.2. UI-limited Client Login . . . . . . . . . . . . . 13
4.1.1.3. UI-limited Client Login Polling . . . . . . . . . 15
4.5. Parameter Processing
4.2. Session Status . . . . . . . . . . . . . . . . . . . . . 15
4.6. RDAP Conformance
4.3. Client Logout . . . . . . . . . . . . . . . . . . . . 16
5. Clients with Limited User Interfaces . . 18
4.4. Token Exchange . . . . . . . . . . 16
5.1. OAuth 2.0 Device Authorization Grant . . . . . . . . . . 16
5.2. Manual Token Management . 18
4.5. Parameter Processing . . . . . . . . . . . . . . . . . . 19
5. RDAP Query Processing . . . . . . . . . . . . . . 17 . . . . . . 19
6. RDAP Conformance . . . . . . . . . . . . . . . . . . . . . . 19
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 17
6.1. 20
7.1. RDAP Extensions Registry . . . . . . . . . . . . . . . . 17
6.2. 20
7.2. JSON Web Token Claims Registry . . . . . . . . . . . . . 18
6.3. 20
7.3. RDAP Query Purpose Registry . . . . . . . . . . . . . . . 18
7. 21
8. Implementation Status . . . . . . . . . . . . . . . . . . . . 21
8. 23
9. Security Considerations . . . . . . . . . . . . . . . . . . . 21
8.1. 24
9.1. Authentication and Access Control . . . . . . . . . . . . 22
9. Acknowledgements 24

10. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . 22
10. . 24
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 22
10.1. 24
11.1. Normative References . . . . . . . . . . . . . . . . . . 22
10.2. 24
11.2. Informative References . . . . . . . . . . . . . . . . . 24 26
Appendix A. Change Log . . . . . . . . . . . . . . . . . . . . . 25 27
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 25 27

1. Introduction

RDAP is specified in multiple documents, including "HTTP Usage in the
Registration Data Access Protocol (RDAP)" [RFC7480], "Security
Services for the Registration Data Access Protocol (RDAP)" [RFC7481],
"Registration Data Access Protocol Query Format" [RFC9082], and "JSON
Responses for the Registration Data Access Protocol (RDAP)"
[RFC9083]. RFC 7481 describes client identification and
authentication services that can be used with RDAP, but it does not
specify how any of these services can (or should) be used with RDAP.

1.1. Problem Statement

The traditional "user name and password" authentication method does
not scale well in the RDAP ecosystem. Assuming that all domain name
and address registries will eventually provide RDAP service, it is
impractical and inefficient for users to secure login credentials
from the hundreds of different server operators. Authentication
methods based on user names and passwords do not provide information
that describes the user in sufficient detail (while protecting the
personal privacy of the user) for server operators to make fine-
grained access control decisions based on the user's identity. The
authentication system used for RDAP needs to address all of these
needs.

1.2. Proposal

A basic level of RDAP service can be provided to users who possess an
identifier issued by a recognized provider who is able to
authenticate and validate the user. The identifiers issued by social
media services, for example, can be used. Users who require higher
levels of service (and who are willing to share more information
about them self to gain access to that service) can secure
identifiers from specialized providers who are or will be able to
provide more detailed information about the user. Server operators
can then make access control decisions based on the identification
information provided by the user.

A federated authentication system would make it easier to operate and
use RDAP by re-using existing identifiers to provide a basic level of
access. It can also provide the ability to collect additional user
identification information, and that information can be shared with
the consent of the user. This document describes a federated
authentication system for RDAP based on OpenID Connect [OIDC] that
meets all of these needs.

2. Conventions Used in This Document

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. Federated Authentication for RDAP

RDAP itself does not include native security services. Instead, RDAP
relies on features that are available in other protocol layers to
provide needed security services including access control,
authentication, authorization, availability, data confidentiality,
data integrity, and identification. A description of each of these
security services can be found in "Internet Security Glossary,
Version 2" [RFC4949]. This document focuses on a federated
authentication system for RDAP that provides services for
authentication, authorization, and identification, allowing a server
operator to make access control decisions. Section 3 of RFC 7481
[RFC7481] describes general considerations for RDAP access control,
authentication, and authorization.

The traditional client-server authentication model requires clients
to maintain distinct credentials for every RDAP server. This
situation can become unwieldy as the number of RDAP servers
increases. Federated authentication mechanisms allow clients to use
one credential to access multiple RDAP servers and reduce client
credential management complexity.

3.1. RDAP and OpenID Connect

OpenID Connect 1.0 [OIDCC] is a decentralized, single sign-on (SSO)
federated authentication system that allows users to access multiple
web resources with one identifier instead of having to create
multiple server-specific identifiers. Users acquire identifiers from
OpenID Providers, or OPs. Relying Parties, or RPs, are applications
(such as RDAP) that outsource their user authentication function to
an OP. OpenID Connect is built on top of the authorization framework
provided by the OAuth 2.0 [RFC6749] protocol.

The OAuth authorization framework describes a method for users to
access protected web resources without having to hand out their
credentials. Instead, clients are issued Access Tokens by
authorization servers with the permission of the resource owners.
Using OpenID Connect and OAuth, multiple RDAP servers can form a
federation and clients can access any server in the federation by
providing one credential registered with any OP in that federation.
The OAuth authorization framework is designed for use with HTTP and
thus can be used with RDAP.

3.1.1. Terminology

This document uses the terms "client" and "server" defined by RDAP
[RFC7480]. An RDAP client performs the role of an OpenID Connect
Core [OIDCC] Entity or End-User. An RDAP server performs the role of
an OpenID Connect Core Relying Party (RP). Additional terms from
Section 1.2 of the OpenID Connect Core specification are incorporated
by reference.

3.1.2. Overview

At a high level, RDAP authentication of a browser-based browser-like client using
OpenID Connect requires completion of the following steps:

1. An RDAP client sends an RDAP "help" query to an RDAP server to
determine the type of OpenID Authorization Server that's used by
the RDAP server. This information is returned in the
rdapConformance section of the response. A value of
"rdap_openidc_local_level_0" indicates that the server uses a
local Authorization Server. A value of
"rdap_openidc_remote_level_0" indicates that the server uses a
remote Authorization Server.
2. An RDAP client (acting as an OpenID End-User) sends a "tokens" "login"
request (see Section 4.2) 4.1) to an RDAP server. The request MUST
include an "id" query parameter if the server uses only a remote
Authorization Server. The "id" query parameter is OPTIONAL if
the server uses a local Authorization Server.

3. The RDAP server (acting as an OpenID Relying Party (RP))
prepares an Authentication Request containing the desired
request parameters.
4. The RDAP server sends the RDAP client and Authentication Request
to an Authorization Server operated by an OpenID Provider (OP)
using an HTTP redirect.
5. The Authorization Server authenticates the RDAP Client. End-User.
6. The Authorization Server obtains RDAP Client consent/
authorization. End-User consent/authorization.
7. The Authorization Server sends the RDAP Client back to the RDAP
server with an Authorization Code using an HTTP redirect.
8. The RDAP server requests a response using the Authorization Code
at the Token Endpoint.
9. The RDAP server receives a response that contains an ID Token
and Access Token in the response body.
10. The RDAP server validates the ID Token and retrieves the RDAP
client's Subject Identifier. claims
associated with the end-user's identity.

The RDAP server can then make identification, authorization, and
access control decisions based on local policies, the ID Token
received from the OP, end-user identity information and the received Claims.
local policies. Note that OpenID Connect describes different process
flows for other types of clients, such as script-based or command
line clients.

3.1.3. RDAP Authentication and Authorization Steps

End-Users MUST possess an identifier (an OpenID) issued by an OP to
use OpenID Connect with RDAP. An OP SHOULD include support for the
claims described in Section 3.1.4 to provide additional information
needed for RDAP End-User authorization. OpenID Connect requires RPs
to register with OPs to use OpenID Connect services for an End-User.
That process is described by the "OpenID Connect Dynamic Client
Registration" protocol [OIDCR].

3.1.3.1. Provider Discovery

An RDAP server/RP needs to receive be able to map an End-User's identifier from to
an End-User
that OP. This can be used to discover the End-User's OP. That process is
required and is documented in accomplished using the OPTIONAL "OpenID Connect
Discovery" protocol
[OIDCD].

3.1.3.2. Authentication Request

Once the OP [OIDCD], but that protocol is known, not widely
implemented and can be unreliable. Out-of-band methods are also
possible and can be more dependable. For example, an RP MUST form an Authentication Request can support
a limited number of OPs and
send it to the OP as described in Section 3 maintain internal associations of those
identifiers with the OPs that issued them. An RP can also ask an
end-user to identify the OP that issued their identifier as part of
an RDAP query workflow. In this case, the RP will need to maintain
state for the association between the user's identifier and the OP in
order to process later queries that rely on passing the access token
and user identifier as authorization parameters. An RP MAY use any
provider discovery approach that is suitable for its operating
environment.

3.1.3.2. Authentication Request

Once the OP is known, an RP MUST form an Authentication Request and
send it to the OP as described in Section 3 of the OpenID Connect
Core protocol [OIDCC]. The authentication path followed
(authorization, implicit, or hybrid) will depend on the
Authentication Request response_type set by the RP. The remainder of
the processing steps described here assume that the Authorization
Code Flow is being used by setting "response_type=code" in the
Authentication Request.

The benefits of using the Authorization Code Flow for authenticating
a human user are described in Section 3.1 of the OpenID Connect Core
protocol. The Implicit Flow is more commonly used by clients
implemented in a web browser using a scripting language; it is
described in Section 3.2 of the OpenID Connect Core protocol. The
Hybrid Flow (described in Section 3.3 of the OpenID Connect Core
protocol) combines elements of the Authorization and Implicit Flows
by returning some tokens from the Authorization Endpoint and others
from the Token Endpoint.

An Authentication Request can contain several parameters. REQUIRED
parameters are specified in Section 3.1.2.1 of the OpenID Connect
Core protocol [OIDCC]. Apart from these parameters, it is
RECOMMENDED that the RP include the optional "login_hint" parameter
in the request, with the value being that of the "id" from the query
component parameter
of the end user's End-User's RDAP "login" request. Passing the "login_hint"
parameter allows a client to pre-fill login form information, so
logging in can be more convenient for users. Other parameters MAY be
included.

The OP receives the Authentication Request and attempts to validate
it as described in Section 3.1.2.2 of the OpenID Connect Core
protocol [OIDCC]. If the request is valid, the OP attempts to
authenticate the End-User as described in Section 3.1.2.3 of the
OpenID Connect Core protocol [OIDCC]. The OP returns an error
response if the request is not valid or if any error is encountered.

3.1.3.3. End-User Authorization

After the End-User is authenticated, the OP MUST obtain authorization
information from the End-User before releasing information to the
RDAP Server/RP. This process is described in Section 3.1.2.4 of the
OpenID Connect Core protocol [OIDCC].

3.1.3.4. Authorization Response and Validation

After the End-User is authenticated, the OP will send a response to
the RP that describes the result of the authorization process in the
form of an Authorization Grant. The RP MUST validate the response.
This process is described in Sections 3.1.2.5 - 3.1.2.7 of the OpenID
Connect Core protocol [OIDCC].

3.1.3.5. Token Processing

The RP sends a Token Request using the Authorization Grant to a Token
Endpoint to obtain a Token Response containing an Access Token, ID
Token, and an OPTIONAL Refresh Token. The RP MUST validate the Token
Response. This process is described in Section 3.1.3 of the OpenID
Connect Core protocol [OIDCC].

3.1.3.6. Delivery of User Information

The set of Claims can be retrieved by sending a request to a UserInfo
Endpoint using the Access Token. The Claims MAY be returned in the
ID Token. The process of retrieving Claims from a UserInfo Endpoint
is described in Section 5.3 of the OpenID Connect Core protocol
[OIDCC].

OpenID Connect specified a set of standard Claims in Section 5.1.
Additional Claims for RDAP are described in Section 3.1.4.

3.1.4. Specialized Claims for RDAP

OpenID Connect claims are pieces of information used to make
assertions about an entity. Section 5 of the OpenID Connect Core
protocol [OIDCC] describes a set of standard claims that can be used
to identify a person. Section 5.1.2 notes that additional claims MAY
be used, and it describes a method to create them.

3.1.4.1. Stated Purpose

There are communities of RDAP users and operators who wish to make
and validate claims about a user's "need to know" when it comes to
requesting access to a resource. For example, a law enforcement
agent or a trademark attorney may wish to be able to assert that they
have a legal right to access a protected resource, and a server
operator will need to be able to receive and validate that claim.
These needs can be met by defining and using an additional "purpose"
claim.

The "purpose" claim identifies the purpose for which access to a
protected resource is being requested. Use of the "purpose" claim is
OPTIONAL; processing of this claim is subject to server acceptance of
the purpose and successful authentication of the End-User.
Unrecognized purpose values MUST be ignored and the associated query
MUST be processed as if the unrecognized purpose value was not
present at all.

The "purpose" value is a case-sensitive string containing a
StringOrURI value as specified in Section 2 of the JSON Web Token
(JWT) specification ([RFC7519]). An example:

{"purpose" : "domainNameControl"}

Purpose values are themselves registered with IANA. Each entry in
the registry contains the following fields:

Value: the purpose string value being registered. Value strings can
contain upper case characters from "A" to "Z", lower case ASCII
characters from "a" to "z", and the underscore ("_") character.
Value strings contain at least one character and no more than 64
characters.

Description: a one- or two-sentence description of the meaning of the
purpose value, how it might be used, and/or how it should be
interpreted by clients and servers.

This registry is operated under the "Specification Required" policy
defined in RFC 5226 ([RFC5226]). The set of initial values used to
populate the registry as described in Section 6.3 7.3 are taken from the
final report (https://www.icann.org/en/system/files/files/final-
report-06jun14-en.pdf) produced by the Expert Working Group on gTLD
Directory Services chartered by the Internet Corporation for Assigned
Names and Numbers (ICANN).

3.1.4.2. Do Not Track

There are also communities of RDAP users and operators who wish to
make and validate claims about a user's wish to not have their
queries logged, tracked, or recorded. For example, a law enforcement
agent may wish to be able to assert that their queries are part of a
criminal investigation and should not be tracked due to a risk of
query exposure compromising the investigation, and a server operator
will need to be able to receive and validate that claim. These needs
can be met by defining and using an additional "do not track" claim.

The "do not track" ("dnt") claim can be used to identify an End-User
that is authorized to perform queries without the End-User's
association with those queries being logged, tracked, or recorded by
the server. Client use of the "dnt" claim is OPTIONAL. Server
operators MUST NOT log, track, or record any association of the query
and the End-User's identity if the End-User is successfully
identified and authorized, the "dnt" claim is present, the value of
the claim is "true", and accepting the claim complies with local
regulations regarding logging and tracking.

The "dnt" value is represented as a JSON boolean literal. An
example:

{"dnt" : true}

No special query tracking processing is required if this claim is not
present or if the value of the claim is "false". Use of this claim
MUST be limited to End-Users who are granted "do not track"
privileges in accordance with service policies and regulations.
Specification of these policies and regulations is beyond the scope
of this document.

4. Protocol Parameters

This specification adds the following protocol parameters to RDAP:

1. A query parameter to request authentication for a specific end-
user identity.
2. A path segment Path segments to request start, stop, and determine the status of an tokens
authenticated session for a specific end-user identity.
3. A query parameter to deliver an Access Token for use with an RDAP
query.

4.1. Client Authentication Request and Response Login

Client authentication is requested by sending a "login" query to an
RDAP server. If the RDAP server supports only remote Authorization
Servers, the "login" query MUST include an End-User identifier that's
delivered using one of three two methods:

1. by adding a query component to an
RDAP request URI using the syntax described in Section 3.4 of RFC
3986 [RFC3986],
2. or by including an HTTP authorization header for the
Basic authentication scheme as described in RFC 7617 [RFC7617], or
3. by including an HTTP authorization header with [RFC7617]. If
the RDAP server supports a Bearer token as
described in RFC 6750 [RFC6750]. local Authorization Servers, the End-User
identifier MAY be omitted. Clients can use any either of these methods.
Servers MUST support all both methods.

The query used to request client authentication is represented as an
OPTIONAL "key=value" pair using a key value of "id" and a value
component that contains the client identifier issued by an OP. An
example for client identifier "user.idp.example":

https://example.com/rdap/domain/example.com?id=user.idp.example

https://example.com/rdap/login?id=user.idp.example

The authorization header for the Basic authentication scheme contains
a Base64-encoded representation of the client identifier issued by an
OP. No password is provided. An example for client identifier
"user.idp.example":

https://example.com/rdap/domain/example.com

https://example.com/rdap/login

Authorization: Basic dXNlci5pZHAuZXhhbXBsZQ==
The HTTP Bearer authorization header contains a Base64url-encoded
representation of the Access Token issued by an OP.

An example that
has been abbreviated for clarity:

https://example.com/rdap/domain/example.com

Authorization: Bearer eyJ0...NiJ9 use with a local Authorization Server:

https://example.com/rdap/login

The response to an authenticated this query MUST use the response structures specified
in RFC 9083 [RFC9083]. Information that In addition, the
end-user is not authorized to receive response MUST be omitted from the
response.

4.2. Token Request and Response

Clients MAY send a request to include an RDAP server to authenticate an end-
user and return tokens (an ID Token, an Access Token, and a Refresh
Token) from an OP that can be then be passed to the RP/RDAP server to
authenticate and process subsequent queries. An Access Token can be
refreshed as described in Section 12
indication of the OpenID Connect Core
protocol [OIDCC] and Section 6 of RFC 6749 [RFC6749]. Clients can
take advantage of this functionality requested operation's success or failure, and, if it is supported by
successful, the OP and
accepted by client identifier associated with the RDAP server. Identity provider authentication is
requested using a "tokens" path segment request, the
claims received from the Authorization Server, and an OPTIONAL query
parameter (the query parameter isn't needed if the RDAP server is
using a local OP) with a key value duration of "id" and a value component that
contains
the client identifier issued by an OP. authorized session.

An example for use
with of a remote OP:

https://example.com/rdap/tokens?id=user.idp.example successful "login" response:

{
"notices": {
"title": "Login Result",
"description": [
"Login succeeded",
[
"Client ID",
"user.idp.example"
],
[
"Claims",
{
"iss": "https://accounts.someprovider.com",
"azp": "729559086898-onapsvnhf2og.apps.someprovider.com",
"aud": "729559086898-onapsvnhf2og.apps.someprovider.com",
"sub": "103892603076825016132",
"email": "user@someprovider.com",
"email_verified": true,
"at_hash": "es5maY5y9jBAWCBMhLokAQ",
"nonce": "dcb29f97c836726ddc074f76fbc21bfd",
"name": "User Person",
"picture": "https://lh3.someprovider.com/a-/AOh14=s96-c",
"given_name": "User",
"family_name": "Person",
"locale": "en",
"iat": 1644239971,
"exp": 1644243571,
"purpose": "domainNameControl",
"dnt": false
}
],
[
"Expires in (seconds)",
3599
]
]
},
"lang": "en-US"
}

Figure 1

An example for use with of a local OP:

https://example.com/rdap/tokens
In addition to any core RDAP response elements, the response failed "login" response:

{
"notices": {
"title": "Login Result",
"description": [
"Login failed",
[
"Client ID",
"user.idp.example"
]
},
"lang": "en-US"
}

Figure 2

4.1.1. Clients with Limited User Interfaces

The flow described in Section 3.1.3 requires an end-user to this
query MUST contain five name-value pairs, interact
with a server using a user interface that can process HTTP. This
will not work well in any order, representing situations where the returned ID Token, Access Token, and Refresh Token. The ID Token client is automated or an
end-user is represented using a key value of "id_token". The Access Token is
represented command line user interface such as curl
(http://curl.haxx.se/) or wget (https://www.gnu.org/software/wget/).
This limitation can be addressed using a key value of "access_token". The Access Token
type is represented using web browser on a key value of "token_type" and second
device.

4.1.1.1. OAuth 2.0 Device Authorization Grant

The "OAuth 2.0 Device Authorization Grant" [RFC8628] provides an
OPTIONAL method to request user authorization from devices that have
an Internet connection, but lack a value of
"bearer" suitable browser for a more
traditional OAuth flow. This method requires a client to use a
second device (such as described in Sections 4.2.2 and 7.1 of RFC 6749
[RFC6749]. The lifetime a smart telephone) that has access to a web
browser for entry of a code sequence that is presented on the Access Token
constrained device.

4.1.1.2. UI-limited Client Login

Client authentication is represented using requested by sending a
key value "login/device" query
to an RDAP server. If the RDAP server supports only remote
Authorization Servers, the "login/device" query MUST include an End-
User identifier that's delivered using one of "expires_in" and two methods: by adding
a numerical value that describes query component to an RDAP request URI using the
lifetime syntax described
in seconds Section 3.4 of RFC 3986 [RFC3986], or by including an HTTP
authorization header for the Access Token Basic authentication scheme as described
in Section 4.2.2
of RFC 6749 [RFC6749]. 7617 [RFC7617]. If the RDAP server supports a local
Authorization Servers, the End-User identifier MAY be omitted.
Clients can use either of these methods. Servers MUST support both
methods.

The Refresh Token query used to request client authentication is represented as an
OPTIONAL "key=value" pair using a key value of "refresh_token". The token values returned in the RDAP
server response MUST be Base64url-encoded as described in RFCs 7515
[RFC7515] "id" and 7519 [RFC7519].

An example (the encoded tokens have been abbreviated for clarity):

{
"access_token" : "eyJ0...NiJ9",
"id_token" : "eyJ0...EjXk",
"token_type" : "bearer",
"expires_in" : "3600",
"refresh_token" : "eyJ0...c8da"
}

Figure 1

An RDAP server a value
component that processes this type of query MUST determine if contains the client identifier is associated with an OP that is recognized and
supported issued by the server. Servers MUST reject queries that include an
identifier associated with an unsupported OP with an HTTP 501 (Not
Implemented) response. OP. An RDAP server that receives a query
containing an identifier associated with a recognized OP MUST perform
the steps required to authenticate the user with the OP
example using a
browser or browser-like wget for client and return encoded tokens to the
client. Note that tokens are typically valid identifier "user.idp.example":

wget -qO- --keep-session-cookies --save-
cookies\https://example.com/rdap/login/device?id=user.idp.example

The authorization header for the Basic authentication scheme contains
a limited period Base64-encoded representation of
time and new tokens will be required when an existing token's
validity period has expired.

The Access Token can then be passed to the server for use with an
RDAP query client identifier issued by including the encoded token in an HTTP Bearer
authorization header [RFC6750].
OP. No password is provided. An example (the encoded token has
been abbreviated for clarity):

https://example.com/rdap/domain/example.com?id=user.idp.example

Authorization: Bearer eyJ0...NiJ9
The RDAP server can retrieve user information (such as claims
associated with the user) from the OP by querying the UserInfo
endpoint using the given Access Token. The user information can then
be used to determine if the uiser is authorized to receive the
requested information. curl and an
authorization header:

curl -H "Authorization: Bearer dXNlci5pZHAuZXhhbXBsZQ=="\-c
cookies.txt https://example.com/rdap/domain/login/device

The response to an authenticated this query MUST use the response structures specified
in RFC 9083 [RFC9083].
Information that In addition, the end-user is not authorized to receive response MUST be
omitted from include an
indication of the response.

4.3. Token Refresh and Revocation

The refresh token returned in requested operation's success or failure, and, if
successful, the token response can be used to
refresh an Access Token. name-value pairs described in Section 3.2 of RFC 8628
[RFC8628].

An Access Token is refreshed using a
"tokens" path segment and a query parameter. The query parameter
includes example of a key value device "login" response (the device_code has been
abbreviated):

{
"notices": {
"title": "Device Login Result",
"description": [
"Login succeeded",
{
"device_code": "AH-1N...iy7yg",
"user_code": "CVYP-SYRC",
"expires_in": 1800,
"interval": 5,
"verification_url": "https:\/\/www.example.net\/device"
}
]
},
"lang": "en-US"
}

Figure 3

4.1.1.3. UI-limited Client Login Polling

After successful processing of "refresh_token" and a Base64url-encoded value
that represents the refresh token. An example:

https://example.com/rdap/tokens?refresh_token=eyJ0...c8da

In addition "login/device" query, the client
MUST send a "login/devicepoll" query to any core RDAP response elements, the response RDAP server to this continue
the login process. This query MUST contain four name-value pairs, in any order, representing
a returned Refresh Token and Access Token. The Refresh Token is
represented using a key value of "refresh_token". The Access Token
is represented using a key value of "access_token". The Access Token
type is represented using a key value of "token_type" and a value of
"bearer" as performs the polling function
described in Sections 4.2.2 and 7.1 of RFC 6749
[RFC6749]. The lifetime of 8628 [RFC8628], allowing the Access Token is represented RDAP server to wait for
the End-User to enter the information returned from the "login/
device" query using a
key value of "expires_in" and a numerical value the interface on their second device. After the
End-User has completed that describes process, or if the
lifetime in seconds process fails or times
out, the OP will respond to the polling requests with an indication
of success or failure. Both should be noted using the Access Token as response
structures described in Section 4.2.2
of RFC 6749 [RFC6749]. 4.1. An example using wget:

wget -qO- --load-cookies cookies.txt\https://example.com/rdap/login/
devicepoll

An example using curl:

curl -b cookies.txt https://example.com/rdap/domain/login/devicepoll

The token values returned in the RDAP server response to this query MUST be Base64url-encoded as described in RFCs 7515
[RFC7515] and 7519 [RFC7519].

Example Access Token refresh use the response (the encoded tokens have been
abbreviated for clarity):

{
"access_token" : "0dac...13b0",
"refresh_token" : "f735...d30c",
"token_type" : "bearer",
"expires_in" : "3600"
}

Figure 2

Access and refresh tokens can be revoked as structures described
in RFC 7009
[RFC7009] by sending Section 4.1. RDAP query processing can continue normally on the
UI-limited device once the "login" process has been completed.

4.2. Session Status

Clients MAY send a request to an RDAP server that contains a
"tokens/revoke" path segment and a query parameter. The query
parameter includes a key value to determine the status
of "token" and an existing login session using a Base64url-encoded
value that represents "session" path segment. This
request MAY include an OPTIONAL "refresh" path segment to refresh the
access token associated with the current session and to extend the
session for a period of time determined by the OP. As described in
RFC 6749 [RFC6749], support for refresh token. tokens is OPTIONAL. An example:

https://example.com/rdap/tokens/revoke?token=f735...d30c

Note that this command will revoke both access RDAP
server MUST determine if the OP supports token refresh and process
the refresh tokens at request by either requesting refresh of the same time. access token
or by returning a response that indicates that token refresh is not
supported by the OP. An example "session" request:

https://example.com/rdap/session

An example "session" request with token refresh included:

https://example.com/rdap/session/refresh

In addition to any core RDAP response elements, the response to this query MUST contain a description
include an indication of the result of
processing requested operation's success or
failure, and, if successful, the revocation request within client identifier associated with
the RDAP "notices" data
structure.

Example session, the claims received from the Authorization Server, and
the duration of the authorized session.

An example without token revocation success:

"notices" :
[ refresh:

{
"title" : "Token Revocation
"notices": {
"title": "Session Status Result",
"description" :
"description": [
"Session status succeeded",
[
"Client ID",
"user.idp.example"
],
[
"Token revocation succeeded.", Refresh Status",
"Token refresh not requested."
]
[
"Expires in (seconds)",
1873
]
[
"Claims",
{
"iss": "https://accounts.someprovider.com",
"azp": "729559086898-onapsvnhf2og.apps.someprovider.com",
"aud": "729559086898-onapsvnhf2og.apps.someprovider.com",
"sub": "103892603076825016132",
"email": "user@someprovider.com",
"email_verified": true,
"at_hash": "es5maY5y9jBAWCBMhLokAQ",
"nonce": "dcb29f97c836726ddc074f76fbc21bfd",
"name": "User Person",
"picture": "https://lh3.someprovider.com/a-/AOh14=s96-c",
"given_name": "User",
"family_name": "Person",
"locale": "en",
"iat": 1644239971,
"exp": 1644243571,
"purpose": "domainNameControl",
"dnt": false
}
],
"lang" :
]
},
"lang": "en-US"
}

Figure 3

Example 4

An example with token revocation failure:

"notices" :
[ refresh:

{
"title" : "Token Revocation
"notices": {
"title": "Session Status Result",
"description" :
"description": [
"Session status succeeded",
[
"Client ID",
"user.idp.example"
],
[
"Token revocation failed.", Refresh Status",
"Token refresh successful."
]
[
"Expires in (seconds)",
3599
]
[
"Claims",
{
"iss": "https://accounts.someprovider.com",
"azp": "729559086898-onapsvnhf2og.apps.someprovider.com",
"aud": "729559086898-onapsvnhf2og.apps.someprovider.com",
"sub": "103892603076825016132",
"email": "user@someprovider.com",
"email_verified": true,
"at_hash": "es5maY5y9jBAWCBMhLokAQ",
"nonce": "dcb29f97c836726ddc074f76fbc21bfd",
"name": "User Person",
"picture": "https://lh3.someprovider.com/a-/AOh14=s96-c",
"given_name": "User",
"family_name": "Person",
"locale": "en",
"iat": 1644239971,
"exp": 1644243571,
"purpose": "domainNameControl",
"dnt": false
}
],
"errorCode" : 400,
"lang" :
]
},
"lang": "en-US"
}

Figure 4

4.4. Token Exchange

ID tokens include 5

4.3. Client Logout

Clients MAY send a request to an audience parameter that contains the OAuth 2.0
client_id of the RP as RDAP server to terminate an audience value. In some operational
scenarios (such as existing
login session. Termination of a session is requested using a
"logout" path segment. An example:

https://example.com/rdap/logout

In addition to any core RDAP response elements, the response MUST
include an indication of the requested operation's success or
failure, and, if successful, the client identifier associated with
the session.

Example "logout" response:

{
"notices": {
"title": "Logout Result",
"description": [
"Logout succeeded",
[
"Client ID",
"user.idp.example"
],
"Token revocation successful."
]
},
"lang": "en-US"
}

Figure 6

Access and refresh tokens can be revoked during the "logout" process
as described in RFC 7009 [RFC7009] if supported by the OP (token
revocation endpoint support is OPTIONAL per RFC 8414 [RFC8414]). If
supported, this feature SHOULD be used to ensure that the tokens are
not mistakenly associated with a future RDAP session. In the absence
of a "logout" query, an RDAP session MUST be terminated by the RDAP
server after a server-defined period of time.

4.4. Token Exchange

ID tokens include an audience parameter that contains the OAuth 2.0
client_id of the RP as an audience value. In some operational
scenarios (such as a client that is providing a proxy service), an RP
can receive tokens with an audience value that does not include the
RP's client_id. These tokens might not be trusted by the RP, and the
RP might refuse to accept the tokens. This situation can be remedied
by having the RP exchange these tokens with the OP for a set of
trusted tokens that reset the audience parameter. This token
exchange protocol is described in RFC 8693 [RFC8693]. This issue is
not visible to the RDAP client and should be managed by the OpenID
implementation used by the RDAP server.

4.5. Parameter Processing

Unrecognized query parameters MUST be ignored. An RDAP server that
processes an authenticated query MUST determine if the end-user
identification information is associated with an OP that is
recognized and supported by the server. Servers MUST reject queries
that include identification information that is not associated with a
supported OP by returning an HTTP 501 (Not Implemented) response. An
RDAP server that receives a query containing identification
information associated with a recognized OP MUST perform the steps
required to authenticate the user with the OP, process the query, and
return an RDAP response that is appropriate for the end user's End-User's level
of authorization and access.

5. RDAP server that receives a query containing tokens associated
with a recognized OP and authenticated end user MUST process the
query and return Query Processing

Once an RDAP response that "login" session is appropriate for the end
user's level of authorization and access. Errors based on processing
either the ID Token or the Access Token MUST be signaled with active, an
appropriate HTTP status code as described in Section 3.1 of RFC 6750
[RFC6750].

On receiving a query containing tokens, the RDAP server MUST validate determine
if the identity information End-User is authorized to perform any queries that are
received from a UserInfo endpoint. It can
do this independently of during the OP, because duration of the response is a JSON
object that contains all the data necessary for validation. The
Access Token can be validated by sending a request using it to the
UserInfo Endpoint and confirming that a successful response is
received. session. This is different from the OpenID Connect Authorization
Code MAY include
rejecting queries outright, and Implicit flows, where the Access Token can be validated
against the at_hash claim from the ID Token. With a query containing
tokens, the Access Token might not validate against the at_hash claim
because the Access Token may have been refreshed since the ID Token
was issued.

An RDAP server it MAY include omitting or otherwise
redacting information that processes requests without needing the UserInfo
claims does End-User is not need to retrieve the claims merely in order authorized to
validate the Access Token. Similarly, an RDAP server that has cached
the UserInfo claims for an end user, in accordance with receive.
Specific processing requirements are beyond the HTTP
headers scope of a previous UserInfo Endpoint response, does not need to
retrieve those claims again in order to re-validate the Access Token.

4.6. RDAP Conformance

RDAP responses that contain values described in this document MUST
indicate conformance with this specification
document. A client can end a session explicitly by including an
rdapConformance ([RFC9083]) value of "rdap_openidc_remote_level_0" or
"rdap_openidc_local_level_0". Both values MAY be present if sending a server
supports both local and remote OpenID Authorization Servers. The
information needed
"logout" query to register this value in the RDAP Extensions
Registry is described in Section 6.1.

Example rdapConformance structure with extension specified:

"rdapConformance" :
[
"rdap_level_0",
"rdap_openidc_remote_level_0"
]

Figure 5

5. Clients with Limited User Interfaces

The flow described in Section 3.1.3 requires an end-user to interact
with a server using a user interface that server. A session can process HTTP. This
will not work well in situations where also be ended
implicitly by the client is automated or an
end-user is using a command line user interface such as curl
(http://curl.haxx.se/) or wget (https://www.gnu.org/software/wget/).
There are multiple ways to address this limitation using a web
browser on a second device. Two are described here.

5.1. OAuth 2.0 Device Authorization Grant

The "OAuth 2.0 Device Authorization Grant" [RFC8628] provides one
method to request user authorization from devices that have an
Internet connection, but lack a suitable browser for a more
traditional OAuth flow. This method requires a client to use a
second device (such as a smart telephone) that has access to server after a web
browser for entry server-defined period of a code sequence that is presented on the
constrained device.

5.2. Manual Token Management

A second method time. The
status of requesting user authorization from a constrained
device is possible by producing and managing tokens manually as
follows:

1. Authenticate with the OP as described in Section 4.2 using a
browser or browser-like client.
2. Store the returned ID Token, Access Token, and Refresh Token
locally.
3. Send a request to the content provider/RP along with the client
ID and Access Token received from the OP.

The Access Token MUST be passed to the RP in an HTTP "Authorization"
header [RFC7235]. The Access Token MUST session can be specified using the
"Bearer" authentication scheme [RFC6750].

Here are two examples using the curl and wget utilities. Start determined at any time by
authenticating with the OP:

https://example.com/rdap/tokens?id=user.idp.example

Save the token information and pass it sending a
"session" query to the RP along with the URI
representing the RDAP query. Using curl (encoded tokens have been
abbreviated server.

An RDAP server MUST maintain session state information for clarity:

curl -H "Authorization: Bearer eyJ0...NiJ9"\-k
https://example.com/rdap/domain/example.com\?id=user.idp.example

Using wget:

wget --header="Authorization: Bearer
eyJ0...NiJ9"\https://example.com/rdap/domain/
example.com\id=user.idp.example

Refresh tokens can be useful to automated or command line clients who
wish the
duration of an active session. This is commonly done using HTTP
cookies as described in RFC 6265 [RFC6265]>. Doing so allows End-
User to continue a session submit queries without having to explicitly re-authenticating an
end user. See Section 4.3 identify and
authenticate themselves for more information. each and every query.

6. RDAP Conformance

RDAP responses that contain values described in this document MUST
indicate conformance with this specification by including an
rdapConformance ([RFC9083]) value of "rdap_openidc_remote_level_0" or
"rdap_openidc_local_level_0". Both values MAY be present if a server
supports both local and remote OpenID Authorization Servers. The
information needed to register this value in the RDAP Extensions
Registry is described in Section 7.1.

Example rdapConformance structure with extension specified:

"rdapConformance" :
[
"rdap_level_0",
"rdap_openidc_remote_level_0"
]

Figure 7

7. IANA Considerations

6.1.

7.1. RDAP Extensions Registry

IANA is requested to register the following values in the RDAP
Extensions Registry:

* Extension identifier: rdap_openidc_remote_level_0
* Registry operator: Any
* Published specification: This document.
* Contact: IESG <iesg@ietf.org>
* Intended usage: This extension describes a federated
authentication method for RDAP using OAuth 2.0, OpenID Connect,
and a remote Authorization Server.

* Extension identifier: rdap_openidc_local_level_0
* Registry operator: Any
* Published specification: This document.
* Contact: IESG <iesg@ietf.org>
* Intended usage: This extension describes a federated
authentication method for RDAP using OAuth 2.0, OpenID Connect,
and a local Authorization Server.

6.2.

7.2. JSON Web Token Claims Registry

IANA is requested to register the following values in the JSON Web
Token Claims Registry:

* Claim Name: "purpose"
* Claim Description: This claim describes the stated purpose for
submitting a request to access a protected RDAP resource.
* Change Controller: IESG
* Specification Document(s): Section 3.1.4.1 of this document.

* Claim Name: "dnt"
* Claim Description: This claim contains a JSON boolean literal that
describes an End-User's "do not track" preference for identity
tracking, logging, or recording when accessing a protected RDAP
resource.
* Change Controller: IESG
* Specification Document(s): Section 3.1.4.2 of this document.

6.3.

7.3. RDAP Query Purpose Registry

IANA is requested to create a new protocol registry to manage RDAP
query purpose values. This registry should appear under its own
heading on IANA's protocol listings, using the same title as the name
of the registry. The information to be registered and the procedures
to be followed in populating the registry are described in
Section 3.1.4.1.

Name of registry: Registration Data Access Protocol (RDAP) Query
Purpose Values

Section at http://www.iana.org/protocols:

Registry Title: Registration Data Access Protocol (RDAP) Query
Purpose Values

Registry Name: Registration Data Access Protocol (RDAP) Query Purpose
Values

Registration Procedure: Specification Required

Reference: This draft

Required information: See Section 3.1.4.1.

Review process: "Specification Required" as described in RFC 5226
[RFC5226].

Size, format, and syntax of registry entries: See Section 3.1.4.1.

Initial assignments and reservations:

-----BEGIN FORM----- Value: domainNameControl Description: Tasks
within the scope of this purpose include creating and managing and
monitoring a registrant's own domain name, including creating the
domain name, updating information about the domain name, transferring
the domain name, renewing the domain name, deleting the domain name,
maintaining a domain name portfolio, and detecting fraudulent use of
the Registrant's own contact information. -----END FORM-----
-----BEGIN FORM----- Value: personalDataProtection Description: Tasks
within the scope of this purpose include identifying the accredited
privacy/proxy provider associated with a domain name and reporting
abuse, requesting reveal, or otherwise contacting the provider.
-----END FORM-----

-----BEGIN FORM----- Value: technicalIssueResolution Description:
Tasks within the scope of this purpose include (but are not limited
to) working to resolve technical issues, including email delivery
issues, DNS resolution failures, and web site functional issues.
-----END FORM-----

-----BEGIN FORM----- Value: domainNameCertification Description:
Tasks within the scope of this purpose include a Certification
Authority (CA) issuing an X.509 certificate to a subject identified
by a domain name. -----END FORM-----

-----BEGIN FORM----- Value: individualInternetUse Description: Tasks
within the scope of this purpose include identifying the organization
using a domain name to instill consumer trust, or contacting that
organization to raise a customer complaint to them or file a
complaint about them. -----END FORM-----

-----BEGIN FORM----- Value: businessDomainNamePurchaseOrSale
Description: Tasks within the scope of this purpose include making
purchase queries about a domain name, acquiring a domain name from a
registrant, and enabling due diligence research. -----END FORM-----

-----BEGIN FORM----- Value: academicPublicInterestDNSRResearch
Description: Tasks within the scope of this purpose include academic
public interest research studies about domain names published in the
registration data service, including public information about the
registrant and designated contacts, the domain name's history and
status, and domain names registered by a given registrant (reverse
query). -----END FORM-----

-----BEGIN FORM----- Value: legalActions Description: Tasks within
the scope of this purpose include investigating possible fraudulent
use of a registrant's name or address by other domain names,
investigating possible trademark infringement, contacting a
registrant/licensee's legal representative prior to taking legal
action and then taking a legal action if the concern is not
satisfactorily addressed. -----END FORM-----
-----BEGIN FORM----- Value: regulatoryAndContractEnforcement
Description: Tasks within the scope of this purpose include tax
authority investigation of businesses with online presence, Uniform
Dispute Resolution Policy (UDRP) investigation, contractual
compliance investigation, and registration data escrow audits.
-----END FORM-----

-----BEGIN FORM----- Value:
criminalInvestigationAndDNSAbuseMitigation Description: Tasks within
the scope of this purpose include reporting abuse to someone who can
investigate and address that abuse, or contacting entities associated
with a domain name during an offline criminal investigation.
-----END FORM-----

-----BEGIN FORM----- Value: dnsTransparency Description: Tasks within
the scope of this purpose involve querying the registration data made
public by registrants to satisfy a wide variety of use cases around
informing the general public. -----END FORM-----

8. Implementation Status

NOTE: Please remove this section and the reference to RFC 7942 prior
to publication as an RFC.

This section records the status of known implementations of the
protocol defined by this specification at the time of posting of this
Internet-Draft, and is based on a proposal described in RFC 7942
[RFC7942]. The description of implementations in this section is
intended to assist the IETF in its decision processes in progressing
drafts to RFCs. Please note that the listing of any individual
implementation here does not imply endorsement by the IETF.
Furthermore, no effort has been spent to verify the information
presented here that was supplied by IETF contributors. This is not
intended as, and must not be construed to be, a catalog of available
implementations or their features. Readers are advised to note that
other implementations may exist.

According to RFC 7942, "this will allow reviewers and working groups
to assign due consideration to documents that have the benefit of
running code, which may serve as evidence of valuable experimentation
and feedback that have made the implemented protocols more mature.
It is up to the individual working groups to use this information as
they see fit".

Version -09 of this specification introduced changes that are
incompatible with earlier implementations. Implementations that are
consistent with this specification will be added as they are
identified.

9. Security Considerations

Security considerations for RDAP can be found in RFC 7481 [RFC7481].
Security considerations for OpenID Connect Core [OIDCC] and OAuth 2.0
[RFC6749] can be found in their reference specifications. OpenID
Connect defines optional mechanisms for robust signing and encryption
that can be used to provide data integrity and data confidentiality
services as needed. Security services for ID Tokens and Access
Tokens (with references to the JWT specification) are described in
the OpenID Connect Core protocol.

8.1.

9.1. Authentication and Access Control

Having completed the client identification, authorization, and
validation process, an RDAP server can make access control decisions
based on a comparison of client-provided information and local
policy. For example, a client who provides an email address (and
nothing more) might be entitled to receive a subset of the
information that would be available to a client who provides an email
address, a full name, and a stated purpose. Development of these
access control policies is beyond the scope of this document.

9. Acknowledgements

10. Acknowledgments

The author would like to acknowledge the following individuals for
their contributions to the development of this document: Tom
Harrison, Russ Housley, Rhys Smith, Jaromir Talir, and Alessandro
Vesely. In addition, the Verisign Registry Services Lab development
team of Joseph Harvey, Andrew Kaizer, Sai Mogali, Anurag Saxena,
Swapneel Sheth, Nitin Singh, and Zhao Zhao provided critical "proof
of concept" implementation experience that helped demonstrate the
validity of the concepts described in this document.

Mario Loffredo provided significant feedback based on implementation
experience that led to welcome improvements in several sections of
this document. His contributions are greatly appreciated.

10.

11. References

10.1.

11.1. Normative References

[OIDC] OpenID Foundation, "OpenID Connect",
<http://openid.net/connect/>.

[OIDCC] OpenID Foundation, "OpenID Connect Core incorporating
errata set 1", November 2014,
<http://openid.net/specs/openid-connect-core-1_0.html>.

[OIDCD] OpenID Foundation, "OpenID Connect Discovery 1.0
incorporating errata set 1", November 2014,
<http://openid.net/specs/openid-connect-discovery-
1_0.html>.

[OIDCR] OpenID Foundation, "OpenID Connect Dynamic Client
Registration 1.0 incorporating errata set 1", November
2014, <http://openid.net/specs/openid-connect-
registration-1_0.html>.

[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>.

[RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
Resource Identifier (URI): Generic Syntax", STD 66,
RFC 3986, DOI 10.17487/RFC3986, January 2005,
<https://www.rfc-editor.org/info/rfc3986>.

[RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an
IANA Considerations Section in RFCs", RFC 5226,
DOI 10.17487/RFC5226, May 2008,
<https://www.rfc-editor.org/info/rfc5226>.

[RFC6265] Barth, A., "HTTP State Management Mechanism", RFC 6265,
DOI 10.17487/RFC6265, April 2011,
<https://www.rfc-editor.org/info/rfc6265>.

[RFC6749] Hardt, D., Ed., "The OAuth 2.0 Authorization Framework",
RFC 6749, DOI 10.17487/RFC6749, October 2012,
<https://www.rfc-editor.org/info/rfc6749>.

[RFC6750] Jones, M. and D. Hardt, "The OAuth 2.0 Authorization
Framework: Bearer Token Usage", RFC 6750,
DOI 10.17487/RFC6750, October 2012,
<https://www.rfc-editor.org/info/rfc6750>.

[RFC7009] Lodderstedt, T., Ed., Dronia, S., and M. Scurtescu, "OAuth
2.0 Token Revocation", RFC 7009, DOI 10.17487/RFC7009,
August 2013, <https://www.rfc-editor.org/info/rfc7009>.

[RFC7230] Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
Protocol (HTTP/1.1): Message Syntax and Routing",
RFC 7230, DOI 10.17487/RFC7230, June 2014,
<https://www.rfc-editor.org/info/rfc7230>.

[RFC7235] Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
Protocol (HTTP/1.1): Authentication", RFC 7235,
DOI 10.17487/RFC7235, June 2014,
<https://www.rfc-editor.org/info/rfc7235>.

[RFC7480] Newton, A., Ellacott, B., and N. Kong, "HTTP Usage in the
Registration Data Access Protocol (RDAP)", STD 95,
RFC 7480, DOI 10.17487/RFC7480, March 2015,
<https://www.rfc-editor.org/info/rfc7480>.

[RFC7481] Hollenbeck, S. and N. Kong, "Security Services for the
Registration Data Access Protocol (RDAP)", STD 95,
RFC 7481, DOI 10.17487/RFC7481, March 2015,
<https://www.rfc-editor.org/info/rfc7481>.

[RFC7515] Jones, M., Bradley, J., and N. Sakimura, "JSON Web
Signature (JWS)", RFC 7515, DOI 10.17487/RFC7515, May
2015, <https://www.rfc-editor.org/info/rfc7515>.

[RFC7519] Jones, M., Bradley, J., and N. Sakimura, "JSON Web Token
(JWT)", RFC 7519, DOI 10.17487/RFC7519, May 2015,
<https://www.rfc-editor.org/info/rfc7519>.

[RFC7617] Reschke, J., "The 'Basic' HTTP Authentication Scheme",
RFC 7617, DOI 10.17487/RFC7617, September 2015,
<https://www.rfc-editor.org/info/rfc7617>.

[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>.

[RFC8628] Denniss, W., Bradley, J., Jones, M., and H. Tschofenig,
"OAuth 2.0 Device Authorization Grant", RFC 8628,
DOI 10.17487/RFC8628, August 2019,
<https://www.rfc-editor.org/info/rfc8628>.

[RFC8693] Jones, M., Nadalin, A., Campbell, B., Ed., Bradley, J.,
and C. Mortimore, "OAuth 2.0 Token Exchange", RFC 8693,
DOI 10.17487/RFC8693, January 2020,
<https://www.rfc-editor.org/info/rfc8693>.

[RFC9082] Hollenbeck, S. and A. Newton, "Registration Data Access
Protocol (RDAP) Query Format", STD 95, RFC 9082,
DOI 10.17487/RFC9082, June 2021,
<https://www.rfc-editor.org/info/rfc9082>.

[RFC9083] Hollenbeck, S. and A. Newton, "JSON Responses for the
Registration Data Access Protocol (RDAP)", STD 95,
RFC 9083, DOI 10.17487/RFC9083, June 2021,
<https://www.rfc-editor.org/info/rfc9083>.

10.2.

11.2. Informative References

[RFC4949] Shirey, R., "Internet Security Glossary, Version 2",
FYI 36, RFC 4949, DOI 10.17487/RFC4949, August 2007,
<https://www.rfc-editor.org/info/rfc4949>.

[RFC7942] Sheffer, Y. and A. Farrel, "Improving Awareness of Running
Code: The Implementation Status Section", BCP 205,
RFC 7942, DOI 10.17487/RFC7942, July 2016,
<https://www.rfc-editor.org/info/rfc7942>.

[RFC8414] Jones, M., Sakimura, N., and J. Bradley, "OAuth 2.0
Authorization Server Metadata", RFC 8414,
DOI 10.17487/RFC8414, June 2018,
<https://www.rfc-editor.org/info/rfc8414>.

Appendix A. Change Log

00: Initial working group version ported from draft-hollenbeck-
regext-rdap-openid-10.
01: Modified ID Token delivery approach to note proper use of an
HTTP bearer authorization header.
02: Modified token delivery approach (Access Token is the bearer
token) to note proper use of an HTTP bearer authorization header,
fixing the change made in -01.
03: Updated OAuth 2.0 Device Authorization Grant description and
reference due to publication of RFC 8628.
04: Updated OAuth 2.0 token exchange description and reference due
to publication of RFC 8693. Corrected the RDAP conformance
identifier to be registered with IANA.
05: Keepalive refresh.
06: Keepalive refresh.
07: Added "login_hint" description to Section 3.1.3.2. Added some
text to Section 3.1.4.2 to note that "do not track" requires
compliance with local regulations.
08: Rework of token management processing in Sections 4 and 5.
09: Updated RDAP specification references. Added text to describe
both local and remote Authorization Server processing. Removed
text that described passing of ID Tokens as query parameters.
10: Updated Section 3.1.3.1. Replaced token processing queries with
"login", "session", and "logout" queries.

Author's Address

Scott Hollenbeck
Verisign Labs
12061 Bluemont Way
Reston, VA 20190
United States of America

Email: shollenbeck@verisign.com
URI: http://www.verisignlabs.com/