wdiff rfc7592.original rfc7592.txt

OAuth Working Group
Internet Engineering Task Force (IETF) J. Richer, Ed.
Internet-Draft
Intended status:
Request for Comments: 7592
Category: Experimental M. Jones
Expires: November 6, 2015
ISSN: 2070-1721 Microsoft
J. Bradley
Ping Identity
M. Machulak
Newcastle University
May 5,
July 2015

OAuth 2.0 Dynamic Client Registration Management Protocol
draft-ietf-oauth-dyn-reg-management-15

Abstract

This specification defines methods for management of dynamic OAuth 2.0
dynamic client registrations for use cases in which the properties of
a registered client may need to be changed during the lifetime of the
client. Not all authorization servers supporting dynamic client
registration will support these management methods.

Status of This Memo

This Internet-Draft document is submitted in full conformance with the
provisions of BCP 78 not an Internet Standards Track specification; it is
published for examination, experimental implementation, and BCP 79.

Internet-Drafts are working documents
evaluation.

This document defines an Experimental Protocol for the Internet
community. This document is a product of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list It represents the consensus of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.

Internet-Drafts are draft documents valid the IETF
community. It has received public review and has been approved for
publication by the Internet Engineering Steering Group (IESG). Not
all documents approved by the IESG are a maximum candidate for any level of
Internet Standard; see Section 2 of RFC 5741.

Information about the current status of six months this document, any errata,
and how to provide feedback on it may be updated, replaced, or obsoleted by other documents obtained at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."

This Internet-Draft will expire on November 6, 2015.
http://www.rfc-editor.org/info/rfc7592.

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Table of Contents

1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Notational Conventions . . . . . . . . . . . . . . . . . 3
1.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
1.3. Protocol Flow . . . . . . . . . . . . . . . . . . . . . . 3 4
2. Client Configuration Endpoint . . . . . . . . . . . . . . . . 5
2.1. Client Read Request . . . . . . . . . . . . . . . . . . . 6
2.2. Client Update Request . . . . . . . . . . . . . . . . . . 6 7
2.3. Client Delete Request . . . . . . . . . . . . . . . . . . 9
3. Client Information Response . . . . . . . . . . . . . . . . . 10
4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11
5. Security Considerations . . . . . . . . . . . . . . . . . . . 12
6. Privacy Considerations . . . . . . . . . . . . . . . . . . . 13
7. Normative References . . . . . . . . . . . . . . . . . . . . 13
Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . 14
Appendix B. Registration Tokens and Client Credentials . . . . . 14
B.1. 15
A.1. Credential Rotation . . . . . . . . . . . . . . . . . . . 15 16
Appendix C. B. Forming the Client Configuration Endpoint URL . . . 15
Appendix D. Document History 16
Acknowledgments . . . . . . . . . . . . . . . . . . 16 . . . . . . . 17
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 18

1. Introduction

In order for an OAuth 2.0 client to utilize an OAuth 2.0
authorization server, the client needs specific information to
interact with the server, including an OAuth 2.0 client identifier to
use with that server. The OAuth "OAuth 2.0 Dynamic Client Registration
Protocol [OAuth.Registration] specification
Protocol" [RFC7591] describes how an OAuth 2.0 client can be
dynamically registered with an authorization server to obtain this
information and how metadata about the client can be registered with
the server.

This specification extends the core registration specification by
defining a set of methods for management of dynamic OAuth 2.0 client
registrations beyond those defined in the core registration
specification. In some situations, the registered metadata of a
client can change over time, either by modification at the
authorization server or by a change in the client software itself.
This specification provides methods for the current registration
state of a client to be queried at the authorization server, methods
for the registration of a client to be updated at the authorization
server, and methods for the client to be unregistered from the
authorization server.

This experimental draft Experimental RFC is intended to encourage development and
deployment of interoperable solutions with the intent that feedback
from this experience will inform a future standard.

1.1. Notational Conventions

The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL', 'SHALL NOT',
'SHOULD', 'SHOULD NOT', 'RECOMMENDED', 'MAY', and 'OPTIONAL' in this
document are to be interpreted as described in [RFC2119].

Unless otherwise noted, all the protocol parameter names and values
are case sensitive.

1.2. Terminology

This specification uses the terms "access token", "authorization
code", "authorization endpoint", "authorization grant",
"authorization server", "client", "client identifier", "client
secret", "grant type", "protected resource", "redirection URI",
"refresh token", "resource owner", "resource server", "response
type", and "token endpoint" defined by OAuth 2.0 [RFC6749] and the
terms defined by the OAuth "OAuth 2.0 Client Dynamic Registration Protocol
[OAuth.Registration]. Protocol"
[RFC7591].

This specification defines the following terms:

Client Configuration Endpoint
OAuth 2.0 endpoint through which registration information for a
registered client can be managed. This URL for this endpoint is
returned by the authorization server in the client information
response.

Registration Access Token
OAuth 2.0 bearer token Bearer Token issued by the authorization server through
the client registration endpoint that is used to authenticate the
caller when accessing the client's registration information at the
client configuration endpoint. This access token is associated
with a particular registered client.

1.3. Protocol Flow

This extends the flow in the OAuth "OAuth 2.0 Dynamic Client Registration
Protocol [OAuth.Registration] specification
Protocol" [RFC7591] as follows:

+--------(A)- Initial Access Token (OPTIONAL)
|
| +----(B)- Software Statement (OPTIONAL)
| |
v v
+-----------+ +---------------+
| |--(C)- Client Registration Request -->| Client |
| | | Registration |
| |<-(D)- Client Information Response ---| Endpoint |
| | +---------------+
| |
| | +---------------+
| Client or |--(E)- Read or Update Request ------->| |
| Developer | | |
| |<-(F)- Client Information Response ---| Client |
| | | Configuration |
| | | Endpoint |
| | | |
| |--(G)- Delete Request --------------->| |
| | | |
| |<-(H)- Delete Confirmation -----------| |
+-----------+ +---------------+

Figure 1: Abstract Extended Dynamic Client Registration Flow

The abstract OAuth 2.0 client dynamic registration flow illustrated
in Figure 1 describes the interaction between the client or developer
and the endpoints defined in this specification and its parent. This
figure does not demonstrate error conditions. This flow includes the
following steps:

(A) Optionally, the client or developer is issued an initial access
token for use with the client registration endpoint. The
method by which the initial access token is issued to the
client or developer is out of scope for this specification.

(B) Optionally, the client or developer is issued a software
statement for use with the client registration endpoint. The
method by which the software statement is issued to the client
or developer is out of scope for this specification.

(C) The client or developer calls the client registration endpoint
with its desired registration metadata, optionally including
the initial access token from (A) if one is required by the
authorization server.

(D) The authorization server registers the client and returns:

* the client's registered metadata,

* a client identifier that is unique to the server,

* a set of client credentials such as a client secret, if
applicable for this client,

* a URI pointing to the client configuration endpoint, and

* a registration access token to be used when calling the
client configuration endpoint.

(E) The client or developer optionally calls the client
configuration endpoint with a read or update request using the
registration access token issued in (D). An update request
contains all of the client's registered metadata.

(F) The authorization server responds with the client's current
configuration, potentially including a new registration access
token and a new set of client credentials such as a client
secret if applicable for this client. If a new registration
access token is issued, it replaces the token issued in (D) for
all subsequent calls to the client configuration endpoint.

(G) The client or developer optionally calls the client
configuration endpoint with a delete request using the
registration access token issued in (D) or (F).

(H) The authorization server deprovisions the client and responds
with a confirmation that the deletion has taken place.

2. Client Configuration Endpoint

The client configuration endpoint is an OAuth 2.0 protected resource
that is provisioned by the server to facilitate viewing, updating,
and deleting a client's registered information. The location of this
endpoint is communicated to the client through the
"registration_client_uri" member of the client information response,
as specified in Section 3. The client MUST use its registration
access token in all calls to this endpoint as an OAuth 2.0 Bearer
Token [RFC6750].

The client configuration endpoint MUST be protected by a transport-
layer security mechanism, as described in Section 5.

Operations on this endpoint are switched through the use of different
HTTP methods [RFC7231]. If an authorization server does not support
a particular method on the client configuration endpoint, it MUST
respond with the appropriate error code.

2.1. Client Read Request

To read the current configuration of the client on the authorization
server, the client makes an HTTP GET request to the client
configuration endpoint, authenticating with its registration access
token.

Following

The following is a non-normative example request (with line wraps for
display purposes only): request:

GET /register/s6BhdRkqt3 HTTP/1.1
Accept: application/json
Host: server.example.com
Authorization: Bearer reg-23410913-abewfq.123483

Upon successful read of the information for a currently active
client, the authorization server responds with an HTTP 200 OK with
content type of "application/json" and a payload, payload as described in
Section 3. Some values in the response, including the
"client_secret" and "registration_access_token", MAY be different
from those in the initial registration response. If the
authorization server includes a new client secret and/or registration
access token in its response, the client MUST immediately discard its
previous client secret and/or registration access token. The value
of the "client_id" MUST NOT change from the initial registration
response.

If the registration access token used to make this request is not
valid, the server MUST respond with an error as described in the
OAuth Bearer Token Usage specification [RFC6750].

If the client does not exist on this server, the server MUST respond
with HTTP 401 Unauthorized and the registration access token used to
make this request SHOULD be immediately revoked.

If the client does not have permission to read its record, the server
MUST return an HTTP 403 Forbidden.

2.2. Client Update Request

To update previously-registered a previously registered client's registration with an
authorization server, the client makes an HTTP PUT request to the
client configuration endpoint with a content type of "application/
json". The HTTP entity payload is a JSON [RFC7159] document
consisting of a JSON object and all parameters as top-level members
of that JSON object. This request is authenticated by the
registration access token issued to the client.

This request MUST include all client metadata fields as returned to
the client from a previous registration, read, or update operation.
The updated client metadata fields request MUST NOT include the
"registration_access_token", "registration_client_uri",
"client_secret_expires_at", or "client_id_issued_at" fields described
in Section 3.

Valid values of client metadata fields in this request MUST replace,
not augment, the values previously associated with this client.
Omitted fields MUST be treated as null or empty values by the server,
indicating the client's request to delete them from the client's
registration. The authorization server MAY ignore any null or empty
value in the request just as any other value.

The client MUST include its "client_id" field in the request, and it
MUST be the same as its currently-issued currently issued client identifier. If the
client includes the "client_secret" field in the request, the value
of this field MUST match the currently-issued currently issued client secret for that
client. The client MUST NOT be allowed to overwrite its existing
client secret with its own chosen value.

For all metadata fields, the authorization server MAY replace any
invalid values with suitable default values, and it MUST return any
such fields to the client in the response.

For example, a client could send the following request to the client
registration endpoint to update the client registration in the above
example with new information:

Following information.

The following is a non-normative example request (with line wraps for
display purposes only): request:

PUT /register/s6BhdRkqt3 HTTP/1.1
Accept: application/json
Host: server.example.com
Authorization: Bearer reg-23410913-abewfq.123483

{
"client_id":"s6BhdRkqt3",
"client_id": "s6BhdRkqt3",
"client_secret": "cf136dc3c1fc93f31185e5885805d",
"redirect_uris":[
"redirect_uris": [
"https://client.example.org/callback",
"https://client.example.org/alt"],
"grant_types": ["authorization_code", "refresh_token"],
"token_endpoint_auth_method": "client_secret_basic",
"jwks_uri": "https://client.example.org/my_public_keys.jwks",
"client_name":"My
"client_name": "My New Example",
"client_name#fr":"Mon
"client_name#fr": "Mon Nouvel Exemple",
"logo_uri":"https://client.example.org/newlogo.png",
"logo_uri#fr":"https://client.example.org/fr/newlogo.png"
"logo_uri": "https://client.example.org/newlogo.png",
"logo_uri#fr": "https://client.example.org/fr/newlogo.png"
}

This example uses client metadata values defined in
[OAuth.Registration]. [RFC7591].

Upon successful update, the authorization server responds with an
HTTP 200 OK Message message with content type "application/json" and a
payload,
payload as described in Section 3. Some values in the response,
including the "client_secret" and "registration_access_token", MAY be
different from those in the initial registration response. If the
authorization server includes a new client secret and/or registration
access token in its response, the client MUST immediately discard its
previous client secret and/or registration access token. The value
of the "client_id" MUST NOT change from the initial registration
response.

If the registration access token used to make this request is not
valid, the server MUST respond with an error as described in the
OAuth Bearer Token Usage specification [RFC6750].

If the client does not exist on this server, the server MUST respond
with HTTP 401 Unauthorized, and the registration access token used to
make this request SHOULD be immediately revoked.

If the client is not allowed to update its records, the server MUST
respond with HTTP 403 Forbidden.

If the client attempts to set an invalid metadata field and the
authorization server does not set a default value, the authorization
server responds with an error as described in [OAuth.Registration]. [RFC7591].

2.3. Client Delete Request

To deprovision itself on the authorization server, the client makes
an HTTP DELETE request to the client configuration endpoint. This
request is authenticated by the registration access token issued to
the client as described in [RFC6749].

Following client.

The following is a non-normative example request (with line wraps for
display purposes only): request:

DELETE /register/s6BhdRkqt3 HTTP/1.1
Host: server.example.com
Authorization: Bearer reg-23410913-abewfq.123483

A successful delete action will invalidate the "client_id",
"client_secret", and "registration_access_token" for this client,
thereby preventing the "client_id" from being used at either the
authorization endpoint or token endpoint of the authorization server.
If possible, the authorization server SHOULD immediately invalidate
all existing authorization grants and currently-active currently active access tokens,
all refresh tokens, and all other tokens associated with this client.

If a client has been successfully deprovisioned, the authorization
server MUST respond with an HTTP 204 No Content message.

If the server does not support the delete method, the server MUST
respond with an HTTP 405 Not Supported.

If the registration access token used to make this request is not
valid, the server MUST respond with an error as described in the
OAuth Bearer Token Usage specification [RFC6750].

If the client does not exist on this server, the server MUST respond
with HTTP 401 Unauthorized and the registration access token used to
make this request SHOULD be immediately revoked, if possible.

If the client is not allowed to delete itself, the server MUST
respond with HTTP 403 Forbidden.

Following

The following is a non-normative example response:

HTTP/1.1 204 No Content
Cache-Control: no-store
Pragma: no-cache

3. Client Information Response

This specification extends the client information response defined in
OAuth
"OAuth 2.0 Client Dynamic Registration [OAuth.Registration], Registration" [RFC7591], which states that
the response contains the client identifier (as well as the client
secret if the client is a confidential client). When used with this
specification, the client information response also contains the
fully qualified URL of the client configuration endpoint (Section 2)
for this specific client that the client or developer may use to
manage the client's registration configuration, as well as a
registration access token that is to be used by the client or
developer to perform subsequent operations at the client
configuration endpoint.

registration_client_uri
REQUIRED. String containing the fully qualified URL of the client
configuration endpoint for this client.

registration_access_token
REQUIRED. Access String containing the access token string to be used at the
client configuration endpoint to perform subsequent operations
upon the client registration.

registration_client_uri
REQUIRED. Fully qualified URL string of the client configuration
endpoint for this client.

Additionally, the authorization server MUST return all registered
metadata about this client, including any fields provisioned by the
authorization server itself. The authorization server MAY reject or
replace any of the client's requested metadata values submitted
during the registration or update requests and substitute them with
suitable values.

The response is an "application/json" document with all parameters as
top-level members of a JSON object [RFC7159].

Following

The following is a non-normative example response:

HTTP/1.1 200 OK
Content-Type: application/json
Cache-Control: no-store
Pragma: no-cache

{
"registration_access_token": "reg-23410913-abewfq.123483",
"registration_client_uri":
"https://server.example.com/register/s6BhdRkqt3",
"client_id":"s6BhdRkqt3",
"client_id": "s6BhdRkqt3",
"client_secret": "cf136dc3c1fc93f31185e5885805d",
"client_id_issued_at":2893256800,
"client_secret_expires_at":2893276800,
"client_name":"My
"client_id_issued_at": 2893256800,
"client_secret_expires_at": 2893276800,
"client_name": "My Example Client",
"client_name#ja-Jpan-JP":
"\u30AF\u30E9\u30A4\u30A2\u30F3\u30C8\u540D",
"redirect_uris":[
"redirect_uris": [
"https://client.example.org/callback",
"https://client.example.org/callback2"],
"grant_types": ["authorization_code", "refresh_token"],
"token_endpoint_auth_method": "client_secret_basic",
"logo_uri": "https://client.example.org/logo.png",
"jwks_uri": "https://client.example.org/my_public_keys.jwks"
}

4. IANA Considerations

This specification registers the following client metadata names and
descriptions in the OAuth "OAuth Dynamic Client Registration Metadata Metadata"
registry established by [OAuth.Registration]: [RFC7591]:

o Client Metadata Name: "registration_access_token"

o Client Metadata Description: OAuth 2.0 bearer token Bearer Token used to access
the client configuration endpoint

o Change controller: Controller: IESG

o Specification document(s): [[ this document ]] Document(s): RFC 7592

o Client Metadata Name: "registration_client_uri"

o Client Metadata Description: Fully qualified URI of the client
registration endpoint

o Change controller: Controller: IESG
o Specification document(s): [[ this document ]] Document(s): RFC 7592

5. Security Considerations

While the client secret can expire, the registration access token
SHOULD NOT expire while a client is still actively registered. If
this token were to expire, a developer or client could be left in a
situation where they have no means of retrieving, updating, or
deleting the client's registration information. Were that the case,
a new registration would be required, thereby generating a new client
identifier. However, to limit the exposure surface of the
registration access token, the registration access token MAY be
rotated when the developer or client does a read or update operation
on the client's client configuration endpoint. As the registration
access tokens are relatively long-term credentials, and since the
registration access token is a Bearer token Token and acts as the sole
authentication for use at the client configuration endpoint, it MUST
be protected by the developer or client as described in the OAuth 2.0
Bearer Token Usage specification [RFC6750].

Since requests to the client configuration endpoint result in the
transmission of clear-text credentials (in the HTTP request and
response), the authorization server MUST require the use of a
transport-layer security mechanism when sending requests to the
endpoint. The server MUST support TLS 1.2 RFC 5246 [RFC5246] and MAY support
additional transport-layer security mechanisms meeting its security
requirements. When using TLS, the client MUST perform a TLS/SSL
server certificate check, per RFC 6125 [RFC6125]. Implementation
security considerations can be found in Recommendations for Secure
Use of TLS and DTLS [RFC7525]. [BCP195].

Since possession of the registration access token authorizes the
holder to potentially read, modify, or delete a client's registration
(including its credentials such as a client_secret), the registration
access token MUST contain sufficient entropy to prevent a random
guessing attack of this token, such as described in [RFC6750] Section 5.2 of
[RFC6750] and [RFC6819] Section 5.1.4.2.2. 5.1.4.2.2 of [RFC6819].

If a client is deprovisioned from a server, any outstanding
registration access token for that client MUST be invalidated at the
same time. Otherwise, this can lead to an inconsistent state wherein
a client could make requests to the client configuration endpoint
where the authentication would succeed but the action would fail
because the client is no longer valid. The authorization server MUST
treat all such requests as if the registration access token was
invalid by returning an HTTP 401 Unauthorized error, as described.

6. Privacy Considerations

This specification poses no additional privacy considerations beyond
those described in the core OAuth "OAuth 2.0 Dynamic Client Registration
[OAuth.Registration] specification.
Protocol" [RFC7591].

7. Normative References

[OAuth.Registration]
Richer, J., Ed., Jones, M., Bradley, J., Machulak, M.,

[BCP195] Sheffer, Y., Holz, R., and P. Hunt, "OAuth 2.0 Dynamic Client Registration Protocol",
draft-ietf-oauth-dyn-reg (work in progress), Saint-Andre,
"Recommendations for Secure Use of Transport Layer
Security (TLS) and Datagram Transport Layer Security
(DTLS)", BCP 195, RFC 7525, DOI 10.17487/RFC7525, May 2015.
2015, <http://www.rfc-editor.org/info/bcp195>.

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

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

[RFC6125] Saint-Andre, P. and J. Hodges, "Representation and
Verification of Domain-Based Application Service Identity
within Internet Public Key Infrastructure Using X.509
(PKIX) Certificates in the Context of Transport Layer
Security (TLS)", RFC 6125, DOI 10.17487/RFC6125, March 2011.
2011, <http://www.rfc-editor.org/info/rfc6125>.

[RFC6749] Hardt, D., Ed., "The OAuth 2.0 Authorization Framework",
RFC 6749, DOI 10.17487/RFC6749, October 2012. 2012,
<http://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. 2012,
<http://www.rfc-editor.org/info/rfc6750>.

[RFC6819] Lodderstedt, T., Ed., McGloin, M., and P. Hunt, "OAuth 2.0
Threat Model and Security Considerations", RFC 6819,
DOI 10.17487/RFC6819, January 2013. 2013,
<http://www.rfc-editor.org/info/rfc6819>.

[RFC7159] Bray, T., Ed., "The JavaScript Object Notation (JSON) Data
Interchange Format", RFC 7159, DOI 10.17487/RFC7159, March 2014.
2014, <http://www.rfc-editor.org/info/rfc7159>.

[RFC7231] Fielding, R. R., Ed. and J. Reschke, Ed., "Hypertext Transfer
Protocol (HTTP/1.1): Semantics and Content", RFC 7231,
DOI 10.17487/RFC7231, June 2014.

[RFC7525] Sheffer, Y., Holz, R., 2014,
<http://www.rfc-editor.org/info/rfc7231>.

[RFC7591] Richer, J., Ed., Jones, M., Bradley, J., Machulak, M., and
P. Saint-Andre,
"Recommendations for Secure Use of Transport Layer
Security (TLS) and Datagram Transport Layer Security
(DTLS)", BCP 195, Hunt, "OAuth 2.0 Dynamic Client Registration Protocol",
RFC 7525, May 2015. 7591, DOI 10.17487/RFC7591, July 2015,
<http://www.rfc-editor.org/info/rfc7591>.

Appendix A. Acknowledgments

The authors thank the OAuth Working Group, the User-Managed Access
Working Group, and the OpenID Connect Working Group participants for
their input to this document. In particular, the following
individuals have been instrumental in their review and contribution
to various versions of this document: Amanda Anganes, Derek Atkins,
Tim Bray, Domenico Catalano, Donald Coffin, Vladimir Dzhuvinov,
George Fletcher, Thomas Hardjono, Phil Hunt, William Kim, Torsten
Lodderstedt, Eve Maler, Josh Mandel, Nov Matake, Tony Nadalin, Nat
Sakimura, Christian Scholz, and Hannes Tschofenig.

Appendix B. Registration Tokens and Client Credentials

Throughout the course of the dynamic registration protocol, there are
three different classes of credentials in play, each with different
properties and targets.

o The initial access token is optionally used by the client or
developer at the registration endpoint. This is an OAuth 2.0
token that is used to authorize the initial client registration
request. The content, structure, generation, and validation of
this token are out of scope for this specification. The
authorization server can use this token to verify that the
presenter is allowed to dynamically register new clients. This
token may be shared among multiple instances of a client to allow
them to each register separately, thereby letting the
authorization server use this token to tie multiple instances of
registered clients (each with their own distinct client
identifier) back to the party to whom the initial access token was
issued, usually an application developer. This token is usually
intended to be used only at the client registration endpoint.

o The registration access token is used by the client or developer
at the client configuration endpoint and represents the holder's
authorization to manage the registration of a client. This is an
OAuth 2.0 bearer token Bearer Token that is issued from the client registration
endpoint in response to a client registration request and is
returned in a client information response. The registration
access token is uniquely bound to the client identifier and is
required to be presented with all calls to the client
configuration endpoint. The registration access token should be
protected as described in [RFC6750] and should not be shared
between instances of a client. If a registration access token is
shared between client instances, one instance could change or
delete registration values for all other instances of the client.
The registration access token can be rotated through the use of
the client read or update method on the client configuration
endpoint. The registration access token is intended to be used
only at the client configuration endpoint.

o The client credentials (such as "client_secret") are optional
depending on the type of client and are used to retrieve OAuth
tokens. Client credentials are most often bound to particular
instances of a client and should not be shared between instances.
Note that since not all types of clients have client credentials,
they cannot be used to manage client registrations at the client
configuration endpoint. The client credentials can be rotated
through the use of the client read or update method on the client
configuration endpoint. The client credentials are intended to be
used only at the token endpoint.

B.1.

A.1. Credential Rotation

The authorization server may be configured to issue new registration
access tokens and/or client credentials (such as a "client_secret")
throughout the lifetime of the client. This may help minimize the
impact of exposed credentials. The authorization server conveys new
registration access tokens and client credentials (if applicable) to
the client in the client information response of either a read or
update request to the client configuration endpoint. The client's
current registration access token and client credentials (if
applicable) MUST be included in the client information response.

The registration access token SHOULD be rotated only in response to a
read or update request to the client configuration endpoint, at which
point endpoint. At this
point, the new registration access token is returned to the client and client,
the old registration access token MUST be discarded by the client client,
and it SHOULD be discarded by the server, if possible. If instead If, instead,
the registration access token were to expire or be invalidated
outside of such requests, the client or developer might be locked out
of managing the client's configuration.

Note that the authorization server decides the frequency of the
credential rotation and not the client. Methods by which the client
can request credential rotation are outside the scope of this
document.

Appendix C. B. Forming the Client Configuration Endpoint URL

The authorization server MUST provide the client with the fully
qualified URL in the "registration_client_uri" element of the Client
Information Response, as specified in Section 3. The authorization
server MUST NOT expect the client to construct or discover this URL
on its own. The client MUST use the URL as given by the server and
MUST NOT construct this URL from component pieces.

Depending on deployment characteristics, the client configuration
endpoint URL may take any number of forms. It is RECOMMENDED that
this endpoint URL be formed through the use of a server-constructed
URL string which that combines the client registration endpoint's URL and
the issued "client_id" for this client, with the latter as either a
path parameter or a query parameter. For example, a client with the
client identifier "s6BhdRkqt3" could be given a client configuration
endpoint URL of "https://server.example.com/register/s6BhdRkqt3"
(path parameter) or of "https://server.example.com/
register?client_id=s6BhdRkqt3" (query parameter). In both of these
cases, the client simply uses the URL as given by the authorization
server.

These common patterns can help the server to more easily determine
the client to which the request pertains, which MUST be matched
against the client to which the registration access token was issued.
If desired, the server MAY simply return the client registration
endpoint URL as the client configuration endpoint URL and change
behavior based on the authentication context provided by the
registration access token.

Appendix D. Document History

[[ to be removed by

Acknowledgments

The authors thank the RFC editor before publication as an RFC ]]

-15

o Added RFC 7525/BCP 195 reference to replace draft reference.

-14

o Clarified all client metadata as JSON arrays, strings, or numbers.

o Clarified experimental nature of OAuth Working Group, the draft.

-13

o Changed rate-limiting suggestion to a complexity requirement.

-12

o Used consistent registry name.

-11

o Fixed a series of nits from Peter Yee's Gen-ART review.

-10
o Updated author information.

o Updated TLS information, imported from Dynamic Registration core.

o Expanded introduction.

o Reformatted diagram text.

o Added privacy considerations section.

-09

o Updated author information.

-08

o Updated HTTP RFC reference.

-07

o Editorial clarifications due to document shepherd feedback.

-06

o Removed TLS 1.0.

o Moved several explanatory sections User-Managed Access
Working Group, and the OpenID Connect Working Group participants for
their input to this document. In particular, the appendix.

o Clarified read operations.

o Added IANA request.

-05

o Removed Phil Hunt from authors list, per request.

o Applied following
individuals have been instrumental in their review and contribution
to various minor editorial changes from working group
comments.

-04

o Incorrect XML uploaded for -03

-03

o Changed draft to be Experimental instead versions of Standards Track.

-02
o Added more context information to the abstract.

-01

o Addressed issues that arose from last call comments on draft-ietf-
oauth-dyn-reg this document: Amanda Anganes, Derek
Atkins, Tim Bray, Domenico Catalano, Donald Coffin, Vladimir
Dzhuvinov, George Fletcher, Thomas Hardjono, Phil Hunt, William Kim,
Torsten Lodderstedt, Eve Maler, Josh Mandel, Nov Matake, Tony
Nadalin, Nat Sakimura, Christian Scholz, and draft-ietf-oauth-dyn-reg-metadata.

-00

o Created from draft-jones-oauth-dyn-reg-management-00. Hannes Tschofenig.

Authors' Addresses

Justin Richer (editor)

Email: ietf@justin.richer.org

Michael B. Jones
Microsoft

Email: mbj@microsoft.com
URI: http://self-issued.info/

John Bradley
Ping Identity

Email: ve7jtb@ve7jtb.com

Maciej Machulak
Newcastle University

Email: maciej.machulak@gmail.com