Internet DRAFT - draft-richer-oauth-dyn-reg-management
draft-richer-oauth-dyn-reg-management
OAuth Working Group J. Richer, Ed.
Internet-Draft The MITRE Corporation
Intended status: Standards Track J. Bradley
Expires: February 28, 2014 Ping Identity
M. Jones
Microsoft
M. Machulak
Newcastle University
August 27, 2013
OAuth 2.0 Dynamic Client Registration Management Protocol
draft-richer-oauth-dyn-reg-management-00
Abstract
This specification defines methods for a dynamically registered OAuth
2.0 client to manage its registration through an OAuth 2.0 protected
web API as well as extended client metadata attributes.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
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Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on February 28, 2014.
Copyright Notice
Copyright (c) 2013 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
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include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Notational Conventions . . . . . . . . . . . . . . . . . 3
1.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
1.3. Protocol Flow . . . . . . . . . . . . . . . . . . . . . . 3
1.4. Registration Tokens and Client Credentials . . . . . . . 5
1.4.1. Credential Rotation . . . . . . . . . . . . . . . . . 6
2. Client Metadata . . . . . . . . . . . . . . . . . . . . . . . 7
2.1. Human Readable Client Metadata . . . . . . . . . . . . . 8
3. Client Configuration Endpoint . . . . . . . . . . . . . . . . 10
3.1. Forming the Client Configuration Endpoint URL . . . . . . 10
3.2. Client Read Request . . . . . . . . . . . . . . . . . . . 10
3.3. Client Update Request . . . . . . . . . . . . . . . . . . 11
3.4. Client Delete Request . . . . . . . . . . . . . . . . . . 14
4. Responses . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4.1. Client Information Response . . . . . . . . . . . . . . . 15
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 17
6. Security Considerations . . . . . . . . . . . . . . . . . . . 17
7. Normative References . . . . . . . . . . . . . . . . . . . . 18
Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . 19
Appendix B. Document History . . . . . . . . . . . . . . . . . . 19
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 24
1. Introduction
In some use-case scenarios, it is desirable or necessary to allow
OAuth 2.0 clients to obtain authorization from an OAuth 2.0
authorization server without requiring the two parties to interact
beforehand. Nevertheless, for the authorization server to accurately
and securely represent to end-users which client is seeking
authorization to access the end-user's resources, a method for
automatic and unique registration of clients is needed. The OAuth
2.0 authorization framework does not define how the relationship
between the client and the authorization server is initialized, or
how a given client is assigned a unique client identifier.
Historically, this has happened out-of-band from the OAuth 2.0
protocol.
This specification extends the OAuth 2.0 Core Dynamic Client
Registration [DynReg] specification (which provides a method for
OAuth 2.0 clients to be registered dynamically with an authorization
server) and defines a mechanism for the client to present the
authorization server with a set of extended metadata, such as a
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display name and icon to be presented to the user during the
authorization step. This draft also provides a mechanism for the
client to read and update this information after the initial
registration action. This draft protects these actions through the
use of an OAuth 2.0 bearer access token that is issued to the client
during registration explicitly for this purpose.
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", "Refresh Token",
"Authorization Code", "Authorization Grant", "Authorization Server",
"Authorization Endpoint", "Client", "Client Identifier", "Client
Secret", "Protected Resource", "Resource Owner", "Resource Server",
and "Token Endpoint" defined by OAuth 2.0 [RFC6749].
This specification defines the following additional 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 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 core dynamic registration [DynReg]
specification as follows:
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+--------(A)- Initial Access Token
|
v
+-----------+ +---------------+
| |--(B)- Client Registration Request -->| Client |
| | | Registration |
| |<-(C)- Client Information Response ---| Endpoint |
| | +---------------+
| |
| | +---------------+
| Client or |--(D)- Read or Update Request ------->| |
| Developer | | |
| |<-(E)- Client Information Response ---| Client |
| | | Configuration |
| | | Endpoint |
| | | |
| |--(F)- Delete Request --------------->| |
| | | |
| |<-(G)- Delete Confirmation -----------| |
+-----------+ +---------------+
Figure 1: Abstract Protocol Flow
The abstract OAuth 2.0 Client dynamic registration flow illustrated
in Figure 1 describes the interaction between the client or developer
and the two 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)
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.
(C)
The authorization server registers the client and returns the
client's registered metadata, a client identifier that is unique
at the server, a set of client credentials such as a client secret
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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.
(D)
The client or developer optionally calls the client configuration
endpoint with a read or update request using the registration
access token issued in (C). An update request contains all of the
client's registered metadata.
(E)
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 (C) for all subsequent
calls to the client configuration endpoint.
(F)
The client or developer optionally calls the client configuration
endpoint with a delete request using the registration access token
issued in (C).
(G)
The authorization server deprovisions the client and responds with
a confirmation that the deletion has taken place.
1.4. 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 between 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 should be
used only at the client registration endpoint.
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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 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 and should not be shared between instances of a client
(otherwise, one instance could change or delete registration
values for all instances of the client). The registration access
token can be rotated through the use of the client read and update
methods on the client configuration endpoint. The registration
access token should 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 and update methods on the
client configuration endpoint. The client credentials can not be
used for authentication at the client registration endpoint or at
the client configuration endpoint.
1.4.1. Credential Rotation
The Authorization Server MAY rotate the client's registration access
token and/or client credentials (such as a "client_secret")
throughout the lifetime of the client. The client can discovery that
these values have changed by reading the client information response
returned from 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 this
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 the new registration access token is returned to the client and
the old registration access token SHOULD be discarded by both
parties. If the registration access token to expire or be rotated
outside of such requests, the client or developer may be locked out
of managing the client's configuration.
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2. Client Metadata
Many OAuth 2.0 clients wish to register different kinds of client
metadata to facilitate authorization and usage of the protected API.
This specification extends the list of client metadata defined in
OAuth 2.0 Core Client Dynamic Registration [DynReg] with the
following fields:
client_name
Human-readable name of the client to be presented to the user. If
omitted, the authorization server MAY display the raw "client_id"
value to the user instead. It is RECOMMENDED that clients always
send this field. The value of this field MAY be internationalized
as described in Human Readable Client Metadata (Section 2.1).
client_uri
URL of the homepage of the client. If present, the server SHOULD
display this URL to the end user in a clickable fashion. It is
RECOMMENDED that clients always send this field. The value of
this field MUST point to a valid web page. The value of this
field MAY be internationalized as described in Human Readable
Client Metadata (Section 2.1).
logo_uri
URL that references a logo for the client. If present, the server
SHOULD display this image to the end user during approval. The
value of this field MUST point to a valid image file. The value
of this field MAY be internationalized as described in Human
Readable Client Metadata (Section 2.1).
scope
Space separated list of scope values (as described in OAuth 2.0
Section 3.3 [RFC6749]) that the client can use when requesting
access tokens. The semantics of values in this list is service
specific. If omitted, an authorization server MAY register a
Client with a default set of scopes.
contacts
Array of email addresses for people responsible for this client.
The authorization server MAY make these addresses available to end
users for support requests for the client. An authorization
server MAY use these email addresses as identifiers for an
administrative page for this client.
tos_uri
URL that points to a human-readable Terms of Service document for
the client. The Authorization Server SHOULD display this URL to
the end-user if it is given. The Terms of Service usually
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describe a contractual relationship between the end-user and the
client that the end-user accepts when authorizing the client. The
value of this field MUST point to a valid web page. The value of
this field MAY be internationalized as described in Human Readable
Client Metadata (Section 2.1).
policy_uri
URL that points to a human-readable Policy document for the
client. The authorization server SHOULD display this URL to the
end-user if it is given. The policy usually describes how an end-
user's data will be used by the client. The value of this field
MUST point to a valid web page. The value of this field MAY be
internationalized as described in Human Readable Client Metadata
(Section 2.1).
jwks_uri
URL for the Client's JSON Web Key Set [JWK] document representing
the client's public keys. The value of this field MUST point to a
valid JWK Set. These keys MAY be used for higher level protocols
that require signing or encryption.
software_id
A identifier for the software that comprises a client. Unlike
"client_id", which is issued by the authorization server and
generally varies between instances, the "software_id" is asserted
by the client software and is intended to be shared between all
copies of the client software. The value for this field MAY be a
UUID [RFC4122]. The identifier SHOULD NOT change when software
version changes or when a new installation instance is detected.
Authorization servers MUST treat this field as self-asserted by
the client and MUST NOT make any trusted decisions on the value of
this field alone.
software_version
A version identifier for the software that comprises a client.
The value of this field is a string that is intended to be
compared using string equality matching. The value of the
"software_version" SHOULD change on any update to the client
software. Authorization servers MUST treat this field as self-
asserted by the client and MUST NOT make any trusted decisions on
the value of this field alone.
2.1. Human Readable Client Metadata
Human-readable client metadata values and client metadata values that
reference human-readable values MAY be represented in multiple
languages and scripts. For example, the values of fields such as
"client_name", "tos_uri", "policy_uri", "logo_uri", and "client_uri"
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might have multiple locale-specific values in some client
registrations.
To specify the languages and scripts, BCP47 [RFC5646] language tags
are added to client metadata member names, delimited by a #
character. Since JSON member names are case sensitive, it is
RECOMMENDED that language tag values used in Claim Names be spelled
using the character case with which they are registered in the IANA
Language Subtag Registry [IANA.Language]. In particular, normally
language names are spelled with lowercase characters, region names
are spelled with uppercase characters, and languages are spelled with
mixed case characters. However, since BCP47 language tag values are
case insensitive, implementations SHOULD interpret the language tag
values supplied in a case insensitive manner. Per the
recommendations in BCP47, language tag values used in metadata member
names should only be as specific as necessary. For instance, using
"fr" might be sufficient in many contexts, rather than "fr-CA" or
"fr-FR".
For example, a client could represent its name in English as
""client_name#en": "My Client"" and its name in Japanese as
""client_name#ja-Jpan-JP":
"\u30AF\u30E9\u30A4\u30A2\u30F3\u30C8\u540D"" within the same
registration request. The authorization server MAY display any or
all of these names to the resource owner during the authorization
step, choosing which name to display based on system configuration,
user preferences or other factors.
If any human-readable field is sent without a language tag, parties
using it MUST NOT make any assumptions about the language, character
set, or script of the string value, and the string value MUST be used
as-is wherever it is presented in a user interface. To facilitate
interoperability, it is RECOMMENDED that clients and servers use a
human-readable field without any language tags in addition to any
language-specific fields, and it is RECOMMENDED that any human-
readable fields sent without language tags contain values suitable
for display on a wide variety of systems.
Implementer's Note: Many JSON libraries make it possible to reference
members of a JSON object as members of an object construct in the
native programming environment of the library. However, while the
"#" character is a valid character inside of a JSON object's member
names, it is not a valid character for use in an object member name
in many programming environments. Therefore, implementations will
need to use alternative access forms for these claims. For instance,
in JavaScript, if one parses the JSON as follows, "var j =
JSON.parse(json);", then the member "client_name#en-us" can be
accessed using the JavaScript syntax "j["client_name#en-us"]".
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3. 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
(Section 4.1). The client MUST use its registration access token in
all calls to this endpoint as an OAuth 2.0 Bearer Token [RFC6750].
Operations on this endpoint are switched through the use of different
HTTP methods [RFC2616]. If an authorization server does not support
a particular method on the client configuration endpoint, it MUST
respond with the appropriate error code.
3.1. 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 (Section 4.1). 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 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.
3.2. Client Read Request
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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 is a non-normative example request (with line wraps for
display purposes only):
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 as described in
Client Information Response (Section 4.1). 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 OAuth
Bearer Token Usage [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.
3.3. Client Update Request
This operation updates a previously-registered client with new
metadata at the authorization server. This request is authenticated
by the registration access token issued to the client.
The client sends an HTTP PUT to the client configuration endpoint
with a content type of "application/json". The HTTP entity payload
is a JSON [RFC4627] document consisting of a JSON object and all
parameters as top- level members of that JSON object.
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This request MUST include all fields described in Client Metadata
(Section 2) as returned to the client from a previous register, read,
or update operation. The client MUST NOT include the
"registration_access_token", "registration_client_uri",
"client_secret_expires_at", or "client_id_issued_at" fields described
in Client Information Response (Section 4.1).
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.
The client MUST include its "client_id" field in the request, and it
MUST be the same as its 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 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:
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Following is a non-normative example request (with line wraps for
display purposes only):
PUT /register/s6BhdRkqt3 HTTP/1.1
Accept: application/json
Host: server.example.com
Authorization: Bearer reg-23410913-abewfq.123483
{
"client_id":"s6BhdRkqt3",
"client_secret": "cf136dc3c1fc93f31185e5885805d",
"redirect_uris":["https://client.example.org/callback",
"https://client.example.org/alt"],
"scope": "read write dolphin",
"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 New Example",
"client_name#fr":"Mon Nouvel Exemple",
"logo_uri":"https://client.example.org/newlogo.png"
"logo_uri#fr":"https://client.example.org/fr/newlogo.png"
}
Upon successful update, the authorization server responds with an
HTTP 200 OK Message with content type "application/json" and a
payload as described in Client Information Response (Section 4.1).
Some values in the response, including the "client_secret" and
r"egistration_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 OAuth
Bearer Token Usage [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
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server responds with an error as described in Client Registration
Error Response [DynReg].
3.4. 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.
Following is a non-normative example request (with line wraps for
display purposes only):
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.
The authorization server SHOULD immediately invalidate all existing
authorization grants and currently-active tokens associated with this
client.
If a client has been successfully deprovisioned, the authorization
server responds 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 OAuth
Bearer Token Usage [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 delete itself, the server MUST
respond with HTTP 403 Forbidden.
Following is a non-normative example response:
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HTTP/1.1 204 No Content
Cache-Control: no-store
Pragma: no-cache
4. Responses
In response to certain requests from the client to either the client
registration endpoint or the client configuration endpoint as
described in this specification, the authorization server sends the
following response bodies.
4.1. Client Information Response
This specification extends the client information response defined in
OAuth 2.0 Core Client Dynamic Registration. The response contains
the client identifier as well as the client secret, if the client is
a confidential client. The response also contains the fully
qualified URL of the client configuration endpoint for this specific
client that the client may use to obtain and update information about
itself. The response also contains a registration access token that
is to be used by the client to perform subsequent operations at the
client configuration endpoint.
client_id
REQUIRED. The unique client identifier, MUST NOT be currently
valid for any other registered client.
client_secret
OPTIONAL. The client secret. If issued, this MUST be unique for
each "client_id". This value is used by confidential clients to
authenticate to the token endpoint as described in OAuth 2.0
[RFC6749] Section 2.3.1.
client_id_issued_at
OPTIONAL. Time at which the Client Identifier was issued. The
time is represented as the number of seconds from
1970-01-01T0:0:0Z as measured in UTC until the date/time.
client_secret_expires_at
REQUIRED if "client_secret" is issued. Time at which the
"client_secret" will expire or 0 if it will not expire. The time
is represented as the number of seconds from 1970-01-01T0:0:0Z as
measured in UTC until the date/time.
registration_access_token
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REQUIRED. Access token that is used at the client configuration
endpoint to perform subsequent operations upon the client
registration.
registration_client_uri
REQUIRED. The fully qualified URL of the client configuration
endpoint for this client. The client MUST use this URL as given
when communicating with the client configuration endpoint.
Additionally, the Authorization Server MUST return all registered
metadata (Section 2) 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 [RFC4627].
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_secret": "cf136dc3c1fc93f31185e5885805d",
"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":["https://client.example.org/callback",
"https://client.example.org/callback2"]
"scope": "read write dolphin",
"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"
}
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5. IANA Considerations
This specification makes no requests of IANA.
6. Security Considerations
Since the client configuration endpoint is an OAuth 2.0 protected
resource, it SHOULD have some rate limiting on failures to prevent
the registration access token from being disclosed though repeated
access attempts.
The authorization server MUST treat all client metadata as self-
asserted. For instance, a rogue client might use the name and logo
for the legitimate client which it is trying to impersonate.
Additionally, a rogue client might try to use the software identifier
or software version of a legitimate client to attempt to associate
itself on the authorization server instances of the legitimate
client. To counteract this, an authorization server needs to take
steps to mitigate this phishing risk by looking at the entire
registration request and client configuration. For instance, an
authorization server could warn if the domain/site of the logo
doesn't match the domain/site of redirect URIs. An authorization
server could also refuse registration from a known software
identifier that is requesting different redirect URIs or a different
client homepage uri. An authorization server can also present
warning messages to end users about dynamically registered clients in
all cases, especially if such clients have been recently registered
or have not been trusted by any users at the authorization server
before.
In a situation where the authorization server is supporting open
client registration, it must be extremely careful with any URL
provided by the client that will be displayed to the user (e.g.
"logo_uri", "tos_uri", "client_uri", and "policy_uri"). For
instance, a rogue client could specify a registration request with a
reference to a drive-by download in the "policy_uri". The
authorization server SHOULD check to see if the "logo_uri",
"tos_uri", "client_uri", and "policy_uri" have the same host and
scheme as the those defined in the array of "redirect_uris" and that
all of these resolve to valid web pages.
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 or updating 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
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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 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 OAuth 2.0
Bearer Token Usage [RFC6750].
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. To prevent accidental
disclosure from such an erroneous situation, 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).
7. Normative References
[DynReg] Richer, J., "OAuth 2.0 Core Dynamic Client Registration",
draft-richer-oauth-dyn-reg-core (work in progress), August
2013.
[IANA.Language]
Internet Assigned Numbers Authority (IANA), "Language
Subtag Registry", 2005.
[JWK] Jones, M., "JSON Web Key (JWK)", draft-ietf-jose-json-web-
key (work in progress), May 2013.
[OAuth.JWT]
Jones, M., Campbell, B., and C. Mortimore, "JSON Web Token
(JWT) Bearer Token Profiles for OAuth 2.0", draft-ietf-
oauth-jwt-bearer (work in progress), March 2013.
[OAuth.SAML2]
Campbell, B., Mortimore, C., and M. Jones, "SAML 2.0
Bearer Assertion Profiles for OAuth 2.0", draft-ietf-
oauth-saml2-bearer (work in progress), March 2013.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2246] Dierks, T. and C. Allen, "The TLS Protocol Version 1.0",
RFC 2246, January 1999.
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[RFC2616] Fielding, R., Gettys, J., Mogul, J., Frystyk, H.,
Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext
Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999.
[RFC4122] Leach, P., Mealling, M., and R. Salz, "A Universally
Unique IDentifier (UUID) URN Namespace", RFC 4122, July
2005.
[RFC4627] Crockford, D., "The application/json Media Type for
JavaScript Object Notation (JSON)", RFC 4627, July 2006.
[RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an
IANA Considerations Section in RFCs", BCP 26, RFC 5226,
May 2008.
[RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security
(TLS) Protocol Version 1.2", RFC 5246, August 2008.
[RFC5646] Phillips, A. and M. Davis, "Tags for Identifying
Languages", BCP 47, RFC 5646, September 2009.
[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, March 2011.
[RFC6749] Hardt, D., "The OAuth 2.0 Authorization Framework", RFC
6749, October 2012.
[RFC6750] Jones, M. and D. Hardt, "The OAuth 2.0 Authorization
Framework: Bearer Token Usage", RFC 6750, October 2012.
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, Nat Sakimura,
Christian Scholz, and Hannes Tschofenig.
Appendix B. Document History
[[ to be removed by the RFC editor before publication as an RFC ]]
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- 00
o Partitioned dyn-reg specification into core and management specs
-14
o Added software_id and software_version metadata fields
o Added direct references to RFC6750 errors in read/update/delete
methods
-13
o Fixed broken example text in registration request and in delete
request
o Added security discussion of separating clients of different grant
types
o Fixed error reference to point to RFC6750 instead of RFC6749
o Clarified that servers must respond to all requests to
configuration endpoint, even if it's just an error code
o Lowercased all Terms to conform to style used in RFC6750
-12
o Improved definition of Initial Access Token
o Changed developer registration scenario to have the Initial Access
Token gotten through a normal OAuth 2.0 flow
o Moved non-normative client lifecycle examples to appendix
o Marked differentiating between auth servers as out of scope
o Added protocol flow diagram
o Added credential rotation discussion
o Called out Client Registration Endpoint as an OAuth 2.0 Protected
Resource
o Cleaned up several pieces of text
-11
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o Added localized text to registration request and response
examples.
o Removed "client_secret_jwt" and "private_key_jwt".
o Clarified "tos_uri" and "policy_uri" definitions.
o Added the OAuth Token Endpoint Authentication Methods registry for
registering "token_endpoint_auth_method" metadata values.
o Removed uses of non-ASCII characters, per RFC formatting rules.
o Changed "expires_at" to "client_secret_expires_at" and "issued_at"
to "client_id_issued_at" for greater clarity.
o Added explanatory text for different credentials (Initial Access
Token, Registration Access Token, Client Credentials) and what
they're used for.
o Added Client Lifecycle discussion and examples.
o Defined Initial Access Token in Terminology section.
-10
o Added language to point out that scope values are service-specific
o Clarified normative language around client metadata
o Added extensibility to token_endpoint_auth_method using absolute
URIs
o Added security consideration about registering redirect URIs
o Changed erroneous 403 responses to 401's with notes about token
handling
o Added example for initial registration credential
-09
o Added method of internationalization for Client Metadata values
o Fixed SAML reference
-08
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o Collapsed jwk_uri, jwk_encryption_uri, x509_uri, and
x509_encryption_uri into a single jwks_uri parameter
o Renamed grant_type to grant_types since it's a plural value
o Formalized name of "OAuth 2.0" throughout document
o Added JWT Bearer Assertion and SAML 2 Bearer Assertion to example
grant types
o Added response_types parameter and explanatory text on its use
with and relationship to grant_types
-07
o Changed registration_access_url to registration_client_uri
o Fixed missing text in 5.1
o Added Pragma: no-cache to examples
o Changed "no such client" error to 403
o Renamed Client Registration Access Endpoint to Client
Configuration Endpoint
o Changed all the parameter names containing "_url" to instead use
"_uri"
o Updated example text for forming Client Configuration Endpoint URL
-06
o Removed secret_rotation as a client-initiated action, including
removing client secret rotation endpoint and parameters.
o Changed _links structure to single value registration_access_url.
o Collapsed create/update/read responses into client info response.
o Changed return code of create action to 201.
o Added section to describe suggested generation and composition of
Client Registration Access URL.
o Added clarifying text to PUT and POST requests to specify JSON in
the body.
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o Added Editor's Note to DELETE operation about its inclusion.
o Added Editor's Note to registration_access_url about alternate
syntax proposals.
-05
o changed redirect_uri and contact to lists instead of space
delimited strings
o removed operation parameter
o added _links structure
o made client update management more RESTful
o split endpoint into three parts
o changed input to JSON from form-encoded
o added READ and DELETE operations
o removed Requirements section
o changed token_endpoint_auth_type back to
token_endpoint_auth_method to match OIDC who changed to match us
-04
o removed default_acr, too undefined in the general OAuth2 case
o removed default_max_auth_age, since there's no mechanism for
supplying a non-default max_auth_age in OAuth2
o clarified signing and encryption URLs
o changed token_endpoint_auth_method to token_endpoint_auth_type to
match OIDC
-03
o added scope and grant_type claims
o fixed various typos and changed wording for better clarity
o endpoint now returns the full set of client information
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o operations on client_update allow for three actions on metadata:
leave existing value, clear existing value, replace existing value
with new value
-02
o Reorganized contributors and references
o Moved OAuth references to RFC
o Reorganized model/protocol sections for clarity
o Changed terminology to "client register" instead of "client
associate"
o Specified that client_id must match across all subsequent requests
o Fixed RFC2XML formatting, especially on lists
-01
o Merged UMA and OpenID Connect registrations into a single document
o Changed to form-paramter inputs to endpoint
o Removed pull-based registration
-00
o Imported original UMA draft specification
Authors' Addresses
Justin Richer (editor)
The MITRE Corporation
Email: jricher@mitre.org
John Bradley
Ping Identity
Email: ve7jtb@ve7jtb.com
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Michael B. Jones
Microsoft
Email: mbj@microsoft.com
URI: http://self-issued.info/
Maciej Machulak
Newcastle University
Email: m.p.machulak@ncl.ac.uk
URI: http://ncl.ac.uk/
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