OAuth 2.0
Dynamic Client Registration Management ProtocolThe MITRE Corporationjricher@mitre.orgMicrosoftmbj@microsoft.comhttp://self-issued.info/Ping Identityve7jtb@ve7jtb.comNewcastle Universitym.p.machulak@ncl.ac.ukhttp://ncl.ac.uk/
Security
OAuth Working GroupThis specification defines methods for management of dynamic OAuth
2.0 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.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 at that
server. The OAuth 2.0 Dynamic Client
Registration Protocol specification 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.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 .Unless otherwise noted, all the protocol parameter names and values
are case sensitive.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 and the terms
defined by the OAuth 2.0 Client
Dynamic Registration Protocol.This specification defines the following terms: 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. 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.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: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.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.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.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 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.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.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.The client or developer optionally calls the
client configuration endpoint with a delete request using the
registration access token issued in (D).The authorization server deprovisions the client
and responds with a confirmation that the deletion has taken
place.Throughout the course of the dynamic registration protocol, there
are three different classes of credentials in play, each with
different properties and targets.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 should be used only at the client
registration endpoint.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 update method
on the client configuration endpoint. The registration access
token should be used only at the client configuration
endpoint.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 update method on the client
configuration endpoint. The client credentials cannot be used for
authentication at the client registration endpoint or at the
client configuration endpoint.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 discover 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 an 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 were to expire or be
rotated outside of such requests, the client or developer might be
locked out of managing the client's configuration.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 . The client MUST use its registration
access token in all calls to this endpoint as an OAuth 2.0 Bearer Token
.Operations on this endpoint are switched through the use of different
HTTP methods. If an authorization server
does not support a particular method on the client configuration
endpoint, it MUST respond with the appropriate error code.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 . 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.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. This operation SHOULD be idempotent -- not causing
changes to the client configuration.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 . Some
values in the response, including the client_secret
and registration_access_token, MAY be
different from those in the initial registration response. However,
since read operations are intended to be idempotent, the read request
itself SHOULD NOT cause changes to the client's registered metadata
values. 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.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.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
document consisting of a JSON object and all parameters as top- level
members of that JSON object.This request MUST include all client metadata fields as returned to
the client from a previous registration, 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 .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
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:Upon successful update, the authorization server responds with an
HTTP 200 OK Message with content type application/json
and a payload, as described in .
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.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 .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.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 MUST responsd 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.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.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.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. REQUIRED. OAuth 2.0 client
identifier. OPTIONAL. OAuth 2.0 client
secret. OPTIONAL. Time at
which the client identifier was issued, as defined by . REQUIRED if
client_secret is issued. Time at which
the client_secret will expire, as
defined by . REQUIRED. Access
token used at the client configuration endpoint to perform
subsequent operations upon the client registration. REQUIRED. Fully
qualified URL 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.This specification makes no requests of IANA.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 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.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.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).OAuth 2.0 Dynamic
Client Registration ProtocolThe MITRE Corporationjricher@mitre.orgMicrosoftmbj@microsoft.comhttp://self-issued.info/Ping Identityve7jtb@ve7jtb.comNewcastle Universitym.p.machulak@ncl.ac.ukhttp://ncl.ac.uk/Oracle Corporationphil.hunt@yahoo.comThe 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.[[ to be removed by the RFC editor before publication as an RFC
]]-05Removed Phil Hunt from authors list, per request.Applied various minor editorial changes from working group
comments.-04Incorrect XML uploaded for -03-03Changed draft to be Experimental instead of Standards Track.-02 Added more context information to the abstract.-01 Addressed issues that arose from last call comments on
draft-ietf-oauth-dyn-reg and draft-ietf-oauth-dyn-reg-metadata.-00 Created from draft-jones-oauth-dyn-reg-management-00.