OAuth Working Group J. Richer
Internet-Draft The MITRE Corporation
Intended status: Standards Track M. Jones
Expires: November 23, 2014 Microsoft
J. Bradley
Ping Identity
M. Machulak
Newcastle University
P. Hunt
Oracle Corporation
May 22, 2014
OAuth 2.0 Dynamic Client Registration Protocol
draft-ietf-oauth-dyn-reg-17
Abstract
This specification defines mechanisms for dynamically registering
OAuth 2.0 clients with authorization servers. Registration requests
send a set of desired client metadata values to the authorization
server and the resulting registration responses return a client
identifier to use at the authorization server and the client metadata
values registered for the client. The client can then use this
registration information to communicate with the authorization server
using the OAuth 2.0 protocol. This specification also defines a set
of common client metadata fields and values for clients to use during
registration.
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-
Drafts is at http://datatracker.ietf.org/drafts/current/.
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 November 23, 2014.
Copyright Notice
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Copyright (c) 2014 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
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include 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.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.1. Notational Conventions . . . . . . . . . . . . . . . . . . 4
1.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4
1.3. Protocol Flow . . . . . . . . . . . . . . . . . . . . . . 6
2. Client Metadata . . . . . . . . . . . . . . . . . . . . . . . 7
2.1. Relationship between Grant Types and Response Types . . . 11
2.2. Human Readable Client Metadata . . . . . . . . . . . . . . 11
2.3. Software Statement . . . . . . . . . . . . . . . . . . . . 12
3. Client Registration Endpoint . . . . . . . . . . . . . . . . . 13
3.1. Client Registration Request . . . . . . . . . . . . . . . 14
3.2. Client Registration Response . . . . . . . . . . . . . . . 17
4. Responses . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.1. Client Information Response . . . . . . . . . . . . . . . 17
4.2. Client Registration Error Response . . . . . . . . . . . . 18
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 20
5.1. OAuth Dynamic Registration Client Metadata Registry . . . 20
5.1.1. Registration Template . . . . . . . . . . . . . . . . 21
5.1.2. Initial Registry Contents . . . . . . . . . . . . . . 21
5.2. OAuth Token Endpoint Authentication Methods Registry . . . 24
5.2.1. Registration Template . . . . . . . . . . . . . . . . 24
5.2.2. Initial Registry Contents . . . . . . . . . . . . . . 25
6. Security Considerations . . . . . . . . . . . . . . . . . . . 25
7. References . . . . . . . . . . . . . . . . . . . . . . . . . . 28
7.1. Normative References . . . . . . . . . . . . . . . . . . . 28
7.2. Informative References . . . . . . . . . . . . . . . . . . 29
Appendix A. Use Cases . . . . . . . . . . . . . . . . . . . . . . 29
A.1. Open versus Protected Dynamic Client Registration . . . . 29
A.1.1. Open Dynamic Client Registration . . . . . . . . . . . 29
A.1.2. Protected Dynamic Client Registration . . . . . . . . 29
A.2. Registration Without or With Software Statements . . . . . 30
A.2.1. Registration Without a Software Statement . . . . . . 30
A.2.2. Registration With a Software Statement . . . . . . . . 30
A.3. Registration by the Client or Developer . . . . . . . . . 30
A.3.1. Registration by the Client . . . . . . . . . . . . . . 30
A.3.2. Registration by the Developer . . . . . . . . . . . . 30
A.4. Client ID per Client Instance or per Client Software . . . 30
A.4.1. Client ID per Client Software Instance . . . . . . . . 30
A.4.2. Client ID Shared Among All Instances of Client
Software . . . . . . . . . . . . . . . . . . . . . . . 31
A.5. Stateful or Stateless Registration . . . . . . . . . . . . 31
A.5.1. Stateful Client Registration . . . . . . . . . . . . . 31
A.5.2. Stateless Client Registration . . . . . . . . . . . . 31
Appendix B. Acknowledgments . . . . . . . . . . . . . . . . . . . 31
Appendix C. Document History . . . . . . . . . . . . . . . . . . 32
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 37
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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 at that server. This specification describes how an OAuth 2.0
client can be dynamically registered with an authorization server to
obtain this information.
As part of the registration process, this specification also defines
a mechanism for the client to present the authorization server with a
set of metadata, such as a set of valid redirection URIs. This
metadata can either be communicated in a self-asserted fashion or as
a set of metadata called a software statement, which can be digitally
signed or MACed; in the case of a software statement, the issuer is
vouching for the validity of the data about the client.
Traditionally, registration of a client with an authorization server
is performed manually. The mechanisms defined in this specification
can be used either for a client to dynamically register itself with
authorization servers or for a client developer to programmatically
register the client with authorization servers.
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",
"response type", and "token endpoint" defined by OAuth 2.0 [RFC6749]
and uses the term "Claim" defined by JSON Web Token (JWT) [JWT].
This specification defines the following terms:
Client Developer
The person or organization that builds a client software package
and prepares it for distribution.
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Client Instance
A deployed instance of a piece of client software.
Client Software
Software implementing an OAuth 2.0 client.
Client Registration Endpoint
OAuth 2.0 endpoint through which a client can be registered at an
authorization server. The means by which the URL for this
endpoint is obtained are out of scope for this specification.
Initial Access Token
OAuth 2.0 access token optionally issued by an Authorization
Server and used to authorize calls to the client registration
endpoint. The type and format of this token are likely service-
specific and are out of scope for this specification. The means
by which the authorization server issues this token as well as the
means by which the registration endpoint validates this token are
out of scope for this specification.
Deployment Organization
An administrative security domain under which, a software API is
deployed and protected by an OAuth 2.0 framework. In simple cloud
deployments, the software API publisher and the deployment
organization may be the same. In other scenarios, a software
publisher may be working with many different deployment
organizations.
Software API Deployment
A deployed instance of a software API that is protected by OAuth
2.0 in a particular deployment organization domain. For any
particular software API, there may be one or more deployments. A
software API deployment typically has an associated OAuth 2.0
authorization server as well as a client registration endpoint.
The means by which endpoints are obtained are out of scope for
this specification.
Software API Publisher
The organization that defines a particular web accessible API that
may deployed in one or more deployment environments. A publisher
may be any commercial, public, private, or open source
organization that is responsible for publishing and distributing
software that may be protected via OAuth 2.0. In some cases a
software API publisher and a client developer may be the same
organization.
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Software Statement
A digitally signed or MACed JSON Web Token (JWT) [JWT] that
asserts metadata values about the client software.
1.3. Protocol Flow
+--------(A)- Initial Access Token (OPTIONAL)
|
| +----(B)- Software Statement (OPTIONAL)
| |
v v
+-----------+ +---------------+
| |--(C)- Client Registration Request -->| Client |
| Client or | | Registration |
| Developer |<-(D)- Client Information Response ---| Endpoint |
| | +---------------+
+-----------+
Figure 1: Abstract 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 endpoint defined in this specification. 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 giving access to 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
at the server, a set of client credentials such as a client secret
if applicable for this client, and possibly other values.
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2. Client Metadata
Clients have a set of metadata values associated with their client
identifier at an authorization server, such as the list of valid
redirect URIs or a display name.
The client metadata values are used in two ways:
o as input values to registration requests, and
o as output values in registration responses.
The following client metadata fields are defined by this
specification. All client metadata fields are OPTIONAL.
redirect_uris
Array of redirect URIs for use in redirect-based flows such as the
authorization code and implicit grant types. It is RECOMMENDED
that clients using these flows register this parameter, and an
authorization server SHOULD require registration of valid redirect
URIs for all clients that use these grant types to protect against
token and credential theft attacks.
token_endpoint_auth_method
The requested authentication method for the token endpoint.
Values defined by this specification are:
* "none": The client is a public client as defined in OAuth 2.0
and does not have a client secret.
* "client_secret_post": The client uses the HTTP POST parameters
defined in OAuth 2.0 section 2.3.1.
* "client_secret_basic": the client uses HTTP Basic defined in
OAuth 2.0 section 2.3.1
Additional values can be defined via the IANA OAuth Token Endpoint
Authentication Methods Registry established in Section 5.2.
Absolute URIs can also be used as values for this parameter
without being registered. If unspecified or omitted, the default
is "client_secret_basic", denoting HTTP Basic Authentication
Scheme as specified in Section 2.3.1 of OAuth 2.0.
grant_types
Array of OAuth 2.0 grant types that the client may use. These
grant types are defined as follows:
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* "authorization_code": The Authorization Code Grant described in
OAuth 2.0 Section 4.1
* "implicit": The Implicit Grant described in OAuth 2.0 Section
4.2
* "password": The Resource Owner Password Credentials Grant
described in OAuth 2.0 Section 4.3
* "client_credentials": The Client Credentials Grant described in
OAuth 2.0 Section 4.4
* "refresh_token": The Refresh Token Grant described in OAuth 2.0
Section 6.
* "urn:ietf:params:oauth:grant-type:jwt-bearer": The JWT Bearer
Grant defined in OAuth JWT Bearer Token Profiles [OAuth.JWT].
* "urn:ietf:params:oauth:grant-type:saml2-bearer": The SAML 2
Bearer Grant defined in OAuth SAML 2 Bearer Token Profiles
[OAuth.SAML2].
Authorization Servers MAY allow for other values as defined in
grant type extensions to OAuth 2.0. The extension process is
described in OAuth 2.0 Section 2.5. If the token endpoint is used
in the grant type, the value of this parameter MUST be the same as
the value of the "grant_type" parameter passed to the token
endpoint defined in the extension.
response_types
Array of the OAuth 2.0 response types that the client may use.
These response types are defined as follows:
* "code": The Authorization Code response described in OAuth 2.0
Section 4.1.
* "token": The Implicit response described in OAuth 2.0 Section
4.2.
Authorization servers MAY allow for other values as defined in
response type extensions to OAuth 2.0. The extension process is
described in OAuth 2.0 Section 2.5. If the authorization endpoint
is used by the grant type, the value of this parameter MUST be the
same as the value of the "response_type" parameter passed to the
authorization endpoint defined in the extension.
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client_name
Human-readable name of the client to be presented to the user
during authorization. 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 Section 2.2.
client_uri
URL of a Web page providing information about 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 Section 2.2.
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
Section 2.2.
scope
Space separated list of scope values (as described in Section 3.3
of OAuth 2.0 [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 strings representing ways to contact people responsible
for this client, typically email addresses. The authorization
server MAY make these addresses available to end users for support
requests for the 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
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 Section 2.2.
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-
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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 Section 2.2.
jwks_uri
URL of the client's JSON Web Key Set [JWK] document containing the
client's public keys. The value of this field MUST point to a
valid JWK Set document. These keys can be used by higher level
protocols that use signing or encryption.
jwks
JSON Web Key Set [JWK] value containing the client's public keys.
The value of this field MUST be a JSON object containing a valid
JWK Set. These keys can be used by higher level protocols that use
signing or encryption. This parameter is intended to be used by
clients that cannot use the "jwks_uri" parameter. For instance, a
native application might not have a location to host the contents
of the JWK Set that would be reachable by the authorization
server. The "jwks_uri" and "jwks" parameters MUST NOT be used
together.
software_id
Identifier for the software that comprises a client. Unlike
"client_id", which is issued by the authorization server and may
vary between instances, the "software_id" is asserted by the
client software and is intended to be shared among all instances
of the client software. The identifier SHOULD NOT change when
software version changes or when a new installation occurs.
software_version
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.
Extensions and profiles of this specification MAY expand this list.
The authorization server MUST ignore any client metadata values sent
by the client that it does not understand.
Client metadata values can either be communicated directly in the
body of a registration request, as described in Section 3.1, or
included as claims in a software statement, as described in
Section 2.3, or a mixture of both. If the same client metadata name
is present in both locations and the software statement is trusted by
the authorization server, the value of a claim in the software
statement MUST take precedence.
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2.1. Relationship between Grant Types and Response Types
The "grant_types" and "response_types" values described above are
partially orthogonal, as they refer to arguments passed to different
endpoints in the OAuth protocol. However, they are related in that
the "grant_types" available to a client influence the
"response_types" that the client is allowed to use, and vice versa.
For instance, a "grant_types" value that includes
"authorization_code" implies a "response_types" value that includes
"code", as both values are defined as part of the OAuth 2.0
authorization code grant. As such, a server supporting these fields
SHOULD take steps to ensure that a client cannot register itself into
an inconsistent state, for example by returning an
"invalid_client_metadata" error response to an inconsistent
registration request.
The correlation between the two fields is listed in the table below.
+-----------------------------------------------+-------------------+
| grant_types value includes: | response_types |
| | value includes: |
+-----------------------------------------------+-------------------+
| authorization_code | code |
| implicit | token |
| password | (none) |
| client_credentials | (none) |
| refresh_token | (none) |
| urn:ietf:params:oauth:grant-type:jwt-bearer | (none) |
| urn:ietf:params:oauth:grant-type:saml2-bearer | (none) |
+-----------------------------------------------+-------------------+
Extensions and profiles of this document that introduce new values to
either the "grant_types" or "response_types" parameter MUST document
all correspondences between these two parameter types.
2.2. 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"
might have multiple locale-specific values in some client
registrations to facilitate use in different locations.
To specify the languages and scripts, BCP47 [RFC5646] language tags
are added to client metadata member names, delimited by a #
character. Since JSON [RFC7159] member names are case sensitive, it
is RECOMMENDED that language tag values used in Claim Names be
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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"]".
2.3. Software Statement
A software statement is a JSON Web Token (JWT) [JWT] that asserts
metadata values about the client software as a bundle. A set of
claims that can be used in a software statement are defined
Section 2. When presented to the authorization server as part of a
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client registration request, the software statement MUST be digitally
signed or MACed using JWS [JWS] and MUST contain an "iss" (issuer)
claim denoting the party attesting to the claims in the software
statement. It is RECOMMENDED that software statements be digitally
signed using the "RS256" signature algorithm, although particular
applications MAY specify the use of different algorithms.
The means by which a client or developer obtains a software statement
are outside the scope of this specification. Some common methods
could include a client developer generating a client-specific JWT
registering with a software API publisher to obtain a software
statement for a class of clients. The software statement is
typically distributed with all instances of a client application.
The criteria by which authorization servers determine whether to
trust and utilize the information in a software statement are beyond
the scope of this specification.
In some cases, authorization servers MAY choose to accept a software
statement value directly as a client identifier in an authorization
request, without a prior dynamic client registration having been
performed. The circumstances under which an authorization server
would do so, and the specific software statement characteristics
required in this case, are beyond the scope of this specification.
3. Client Registration Endpoint
The client registration endpoint is an OAuth 2.0 endpoint defined in
this document that is designed to allow a client to be registered
with the authorization server. The client registration endpoint MUST
accept HTTP POST messages with request parameters encoded in the
entity body using the "application/json" format. The client
registration endpoint MUST be protected by a transport-layer security
mechanism, and the server MUST support TLS 1.2 RFC 5246 [RFC5246]
and/or TLS 1.0 [RFC2246] and MAY support additional transport-layer
mechanisms meeting its security requirements. When using TLS, the
client MUST perform a TLS/SSL server certificate check, per RFC 6125
[RFC6125].
The client registration endpoint MAY be an OAuth 2.0 protected
resource and accept an initial access token in the form of an OAuth
2.0 [RFC6749] access token to limit registration to only previously
authorized parties. The method by which the initial access token is
obtained by the client or developer is generally out-of-band and is
out of scope for this specification. The method by which the initial
access token is verified and validated by the client registration
endpoint is out of scope for this specification.
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To support open registration and facilitate wider interoperability,
the client registration endpoint SHOULD allow registration requests
with no authorization (which is to say, with no initial access token
in the request). These requests MAY be rate-limited or otherwise
limited to prevent a denial-of-service attack on the client
registration endpoint.
The client registration endpoint MUST ignore all parameters it does
not understand.
3.1. Client Registration Request
This operation registers a client with the authorization server. The
authorization server assigns this client a unique client identifier,
optionally assigns a client secret, and associates the metadata given
in the request with the issued client identifier. The request
includes any client metadata parameters being specified for the
client during the registration. The authorization server MAY
provision default values for any items omitted in the client
metadata.
To register, the client or developer sends an HTTP POST to the client
registration endpoint with a content type of "application/json". The
HTTP Entity Payload is a JSON [RFC7159] document consisting of a JSON
object and all requested client metadata values as top-level members
of that JSON object.
Client metadata values may also be provided in a software statement,
as described in Section 2.3. Software statements are included in the
requesting JSON object using this member:
software_statement
A software statement containing client metadata values about the
client software as claims.
For example, if the server supports open registration (with no
initial access token), the client could send the following
registration request to the client registration endpoint:
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The following is a non-normative example request not using an initial
access token (with line wraps within values for display purposes
only):
POST /register HTTP/1.1
Content-Type: application/json
Accept: application/json
Host: server.example.com
{
"redirect_uris":[
"https://client.example.org/callback",
"https://client.example.org/callback2"],
"client_name":"My Example Client",
"client_name#ja-Jpan-JP":
"\u30AF\u30E9\u30A4\u30A2\u30F3\u30C8\u540D",
"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",
"example_extension_parameter": "example_value"
}
Alternatively, if the server supports authorized registration, the
developer or the client will be provisioned with an initial access
token. (The method by which the initial access token is obtained is
out of scope for this specification.) The developer or client sends
the following authorized registration request to the client
registration endpoint. Note that the initial access token sent in
this example as an OAuth 2.0 Bearer Token [RFC6750], but any OAuth
2.0 token type could be used by an authorization server.
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The following is a non-normative example request using an initial
access token (with line wraps within values for display purposes
only):
POST /register HTTP/1.1
Content-Type: application/json
Accept: application/json
Authorization: Bearer ey23f2.adfj230.af32-developer321
Host: server.example.com
{
"redirect_uris":["https://client.example.org/callback",
"https://client.example.org/callback2"],
"client_name":"My Example Client",
"client_name#ja-Jpan-JP":
"\u30AF\u30E9\u30A4\u30A2\u30F3\u30C8\u540D",
"token_endpoint_auth_method":"client_secret_basic",
"policy_uri":"https://client.example.org/policy.html",
"jwks":{"keys":[{...omitted for brevity...}]},
"example_extension_parameter": "example_value"
}
In the following example, some registration parameters are conveyed
as claims in a software statement, while some values specific to the
client instance are conveyed as regular parameters (with line wraps
within values for display purposes only):
POST /register HTTP/1.1
Content-Type: application/json
Accept: application/json
Host: server.example.com
{
"redirect_uris":[
"https://client.example.org/callback",
"https://client.example.org/callback2"
],
"software_statement":"eyJhbGciOiJFUzI1NiJ9.
eyJpc3Mi[...omitted for brevity...].
J9l-ZhwP[...omitted for brevity...]",
"scope":"read write",
"example_extension_parameter":"example_value"
}
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3.2. Client Registration Response
Upon successful registration, the authorization server returns a
client identifier for the client. The server responds with an HTTP
201 Created code and a body of type "application/json" with content
as described in Section 4.1.
Upon an unsuccessful registration, the authorization server responds
with an error, as described in Section 4.2.
4. Responses
The following responses are sent in response to registration
requests.
4.1. Client Information Response
The response contains the client identifier as well as the client
secret, if the client is a confidential client. The response MAY
contain additional fields as specified by extensions to this
specification.
client_id
REQUIRED. OAuth 2.0 client identifier. It SHOULD NOT be
currently valid for any other registered client, though an
Authorization Server MAY issue the same client identifier to
multiple instances of a registered client, at its discretion.
client_secret
OPTIONAL. OAuth 2.0 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.
Additionally, the Authorization Server MUST return all registered
metadata about this client, including any fields provisioned by the
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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].
If a software statement was used as part of the registration, its
value MUST be returned in the response along with other metadata.
Client metadata elements used from the software statement MUST also
be returned directly as top-level client metadata values in the
registration response (possibly with different values, since the
values requested and the values used may differ).
Following is a non-normative example response:
HTTP/1.1 200 OK
Content-Type: application/json
Cache-Control: no-store
Pragma: no-cache
{
"client_id":"s6BhdRkqt3",
"client_secret": "cf136dc3c1fc93f31185e5885805d",
"client_id_issued_at":2893256800,
"client_secret_expires_at":2893276800,
"redirect_uris":[
"https://client.example.org/callback",
"https://client.example.org/callback2"],
"grant_types": ["authorization_code", "refresh_token"],
"client_name":"My Example Client",
"client_name#ja-Jpan-JP":
"\u30AF\u30E9\u30A4\u30A2\u30F3\u30C8\u540D",
"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",
"example_extension_parameter": "example_value"
}
4.2. Client Registration Error Response
When an OAuth 2.0 error condition occurs, such as the client
presenting an invalid initial access token, the authorization server
returns an error response appropriate to the OAuth 2.0 token type.
When a registration error condition occurs, the authorization server
returns an HTTP 400 status code (unless otherwise specified) with
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content type "application/json" consisting of a JSON object [RFC7159]
describing the error in the response body.
The JSON object contains two members:
error
Single ASCII error code string.
error_description
Human-readable ASCII text description of the error used for
debugging.
This specification defines the following error codes:
invalid_redirect_uri
The value of one or more redirection URIs is invalid.
invalid_client_metadata
The value of one of the client metadata fields is invalid and the
server has rejected this request. Note that an Authorization
server MAY choose to substitute a valid value for any requested
parameter of a client's metadata.
invalid_software_statement
The software statement presented is invalid.
unapproved_software_statement
The software statement presented is not approved for use by this
authorization server.
Following is a non-normative example of an error response resulting
from a redirect URI that has been blacklisted by the authorization
server (with line wraps within values for display purposes only):
HTTP/1.1 400 Bad Request
Content-Type: application/json
Cache-Control: no-store
Pragma: no-cache
{
"error": "invalid_redirect_uri",
"error_description": "The redirect URI http://sketchy.example.com
is not allowed by this server."
}
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Following is a non-normative example of an error response resulting
from an inconsistent combination of "response_types" and
"grant_types" values (with line wraps within values for display
purposes only):
HTTP/1.1 400 Bad Request
Content-Type: application/json
Cache-Control: no-store
Pragma: no-cache
{
"error": "invalid_client_metadata",
"error_description": "The grant type 'authorization_code' must be
registered along with the response type 'code' but found only
'implicit' instead."
}
5. IANA Considerations
5.1. OAuth Dynamic Registration Client Metadata Registry
This specification establishes the OAuth Dynamic Registration Client
Metadata registry.
OAuth registration client metadata values are registered with a
Specification Required ([RFC5226]) after a two-week review period on
the oauth-ext-review@ietf.org mailing list, on the advice of one or
more Designated Experts. However, to allow for the allocation of
values prior to publication, the Designated Expert(s) may approve
registration once they are satisfied that such a specification will
be published.
Registration requests must be sent to the oauth-ext-review@ietf.org
mailing list for review and comment, with an appropriate subject
(e.g., "Request to register OAuth Dynamic Registration Client
Metadata name: example").
Within the review period, the Designated Expert(s) will either
approve or deny the registration request, communicating this decision
to the review list and IANA. Denials should include an explanation
and, if applicable, suggestions as to how to make the request
successful.
IANA must only accept registry updates from the Designated Expert(s)
and should direct all requests for registration to the review mailing
list.
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5.1.1. Registration Template
Client Metadata Name:
The name requested (e.g., "example"). This name is case
sensitive. Names that match other registered names in a case
insensitive manner SHOULD NOT be accepted.
Client Metadata Description:
Brief description of the metadata value (e.g., "Example
description").
Change controller:
For Standards Track RFCs, state "IETF". For others, give the name
of the responsible party. Other details (e.g., postal address,
email address, home page URI) may also be included.
Specification document(s):
Reference to the document(s) that specify the token endpoint
authorization method, preferably including a URI that can be used
to retrieve a copy of the document(s). An indication of the
relevant sections may also be included but is not required.
5.1.2. Initial Registry Contents
The initial contents of the OAuth Dynamic Registration Client
Metadata registry are:
o Client Metadata Name: "redirect_uris"
o Client Metadata Description: Array of redirect URIs for use in
redirect-based flows
o Change controller: IESG
o Specification document(s): [[ this document ]]
o Client Metadata Name: "token_endpoint_auth_method"
o Client Metadata Description: Requested authentication method for
the token endpoint
o Change controller: IESG
o Specification document(s): [[ this document ]]
o Client Metadata Name: "grant_types"
o Client Metadata Description: Array of OAuth 2.0 grant types that
the client may use
o Change controller: IESG
o Specification document(s): [[ this document ]]
o Client Metadata Name: "response_types"
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o Client Metadata Description: Array of the OAuth 2.0 response types
that the client may use
o Change controller: IESG
o Specification document(s): [[ this document ]]
o Client Metadata Name: "client_name"
o Client Metadata Description: Human-readable name of the client to
be presented to the user
o Change Controller: IESG
o Specification Document(s): [[ this document ]]
o Client Metadata Name: "client_uri"
o Client Metadata Description: URL of a Web page providing
information about the client
o Change Controller: IESG
o Specification Document(s): [[ this document ]]
o Client Metadata Name: "logo_uri"
o Client Metadata Description: URL that references a logo for the
client
o Change Controller: IESG
o Specification Document(s): [[ this document ]]
o Client Metadata Name: "scope"
o Client Metadata Description: Space separated list of scope values
o Change Controller: IESG
o Specification Document(s): [[ this document ]]
o Client Metadata Name: "contacts"
o Client Metadata Description: Array of strings representing ways to
contact people responsible for this client, typically email
addresses
o Change Controller: IESG
o Specification document(s): [[ this document ]]
o Client Metadata Name: "tos_uri"
o Client Metadata Description: URL that points to a human-readable
Terms of Service document for the client
o Change Controller: IESG
o Specification Document(s): [[ this document ]]
o Client Metadata Name: "policy_uri"
o Client Metadata Description: URL that points to a human-readable
Policy document for the client
o Change Controller: IESG
o Specification Document(s): [[ this document ]]
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o Client Metadata Name: "jwks_uri"
o Client Metadata Description: URL for the client's JSON Web Key Set
[JWK] document representing the client's public keys
o Change Controller: IESG
o Specification Document(s): [[ this document ]]
o Client Metadata Name: "jwks"
o Client Metadata Description: The client's JSON Web Key Set [JWK]
document representing the client's public keys
o Change Controller: IESG
o Specification Document(s): [[ this document ]]
o Client Metadata Name: "software_id"
o Client Metadata Description: Identifier for the software that
comprises a client
o Change Controller: IESG
o Specification Document(s): [[ this document ]]
o Client Metadata Name: "software_version"
o Client Metadata Description: Version identifier for the software
that comprises a client
o Change Controller: IESG
o Specification Document(s): [[ this document ]]
o Client Metadata Name: "client_id"
o Client Metadata Description: Client identifier
o Change Controller: IESG
o Specification Document(s): [[ this document ]]
o Client Metadata Name: "client_secret"
o Client Metadata Description: Client secret
o Change Controller: IESG
o Specification Document(s): [[ this document ]]
o Client Metadata Name: "client_id_issued_at"
o Client Metadata Description: Time at which the client identifier
was issued
o Change Controller: IESG
o Specification Document(s): [[ this document ]]
o Client Metadata Name: "client_secret_expires_at"
o Client Metadata Description: Time at which the client secret will
expire
o Change Controller: IESG
o Specification Document(s): [[ this document ]]
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5.2. OAuth Token Endpoint Authentication Methods Registry
This specification establishes the OAuth Token Endpoint
Authentication Methods registry.
Additional values for use as "token_endpoint_auth_method" metadata
values are registered with a Specification Required ([RFC5226]) after
a two-week review period on the oauth-ext-review@ietf.org mailing
list, on the advice of one or more Designated Experts. However, to
allow for the allocation of values prior to publication, the
Designated Expert(s) may approve registration once they are satisfied
that such a specification will be published.
Registration requests must be sent to the oauth-ext-review@ietf.org
mailing list for review and comment, with an appropriate subject
(e.g., "Request to register token_endpoint_auth_method value:
example").
Within the review period, the Designated Expert(s) will either
approve or deny the registration request, communicating this decision
to the review list and IANA. Denials should include an explanation
and, if applicable, suggestions as to how to make the request
successful.
IANA must only accept registry updates from the Designated Expert(s)
and should direct all requests for registration to the review mailing
list.
5.2.1. Registration Template
Token Endpoint Authorization Method Name:
The name requested (e.g., "example"). This name is case
sensitive. Names that match other registered names in a case
insensitive manner SHOULD NOT be accepted.
Change controller:
For Standards Track RFCs, state "IETF". For others, give the name
of the responsible party. Other details (e.g., postal address,
email address, home page URI) may also be included.
Specification document(s):
Reference to the document(s) that specify the token endpoint
authorization method, preferably including a URI that can be used
to retrieve a copy of the document(s). An indication of the
relevant sections may also be included but is not required.
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5.2.2. Initial Registry Contents
The initial contents of the OAuth Token Endpoint Authentication
Methods registry are:
o Token Endpoint Authorization Method Name: "none"
o Change controller: IESG
o Specification document(s): [[ this document ]]
o Token Endpoint Authorization Method Name: "client_secret_post"
o Change controller: IESG
o Specification document(s): [[ this document ]]
o Token Endpoint Authorization Method Name: "client_secret_basic"
o Change controller: IESG
o Specification document(s): [[ this document ]]
6. Security Considerations
Since requests to the client registration 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
registration endpoint. The server MUST support TLS 1.2 RFC 5246
[RFC5246] and/or TLS 1.0 [RFC2246] and MAY support additional
transport-layer mechanisms meeting its security requirements. When
using TLS, the client MUST perform a TLS/SSL server certificate
check, per RFC 6125 [RFC6125].
For clients that use redirect-based grant types such as
"authorization_code" and "implicit", authorization servers SHOULD
require clients to register their "redirect_uris" in full. Requiring
clients to do so can help mitigate attacks where rogue actors inject
and impersonate a validly registered client and intercept its
authorization code or tokens through an invalid redirect URI or open
redirector.
Public clients MAY register with an authorization server using this
protocol, if the authorization server's policy allows them. Public
clients use a "none" value for the "token_endpoint_auth_method"
metadata field and are generally used with the "implicit" grant type.
Often these clients will be short-lived in-browser applications
requesting access to a user's resources and access is tied to a
user's active session at the authorization server. Since such
clients often do not have long-term storage, it's possible that such
clients would need to re-register every time the browser application
is loaded. Additionally, such clients may not have ample opportunity
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to unregister themselves using the delete action before the browser
closes. To avoid the resulting proliferation of dead client
identifiers, an authorization server MAY decide to expire
registrations for existing clients meeting certain criteria after a
period of time has elapsed.
Since different OAuth 2.0 grant types have different security and
usage parameters, an authorization server MAY require separate
registrations for a piece of software to support multiple grant
types. For instance, an authorization server might require that all
clients using the "authorization_code" grant type make use of a
client secret for the "token_endpoint_auth_method", but any clients
using the "implicit" grant type do not use any authentication at the
token endpoint. In such a situation, a server MAY disallow clients
from registering for both the "authorization_code" and "implicit"
grant types simultaneously. Similarly, the "authorization_code"
grant type is used to represent access on behalf of an end user, but
the "client_credentials" grant type represents access on behalf of
the client itself. For security reasons, an authorization server
could require that different scopes be used for these different use
cases, and as a consequence it MAY disallow these two grant types
from being registered together by the same client. In all of these
cases, the authorization server would respond with an
"invalid_client_metadata" error response.
Unless used as a claim in a software statement, the authorization
server MUST treat all client metadata as self-asserted. For
instance, a rogue client might use the name and logo of a legitimate
client that 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 with instances of the legitimate client. To
counteract this, an authorization server needs to take steps to
mitigate this risk by looking at the entire registration request and
client configuration. For instance, an authorization server could
issue a warning if the domain/site of the logo doesn't match the
domain/site of redirect URIs. An authorization server could also
refuse registration requests 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
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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 URIs resolve to valid web pages.
Clients MAY use both the direct JSON object and the JWT-encoded
software statement to present client metadata to the authorization
server as part of the registration request. A software statement is
cryptographically protected and represents claims made by the issuer
of the statement, while the JSON object represents the self-asserted
claims made by the client or developer directly. If the software
statement is valid and trusted, the values of client metadata within
the software statement MUST take precedence over those metadata
values presented in the plain JSON object, which could have been
modified en route.
The software statement is an item that is self-asserted by the
client, even though its contents have been digitally signed or MACed
by the issuer of the software statement. As such, presentation of
the software statement is not sufficient in most cases to fully
identity a piece of client software. An initial access token, in
contrast, does not necessarily contain information about a particular
piece of client software but instead represents authorization to use
the registration endpoint. An authorization server MUST consider the
full registration request, including the software statement, initial
access token, and JSON client metadata values, when deciding whether
to honor a given registration request.
Since a client identifier is a public value that can be used to
impersonate a client at the authorization endpoint, an authorization
server that decides to issue the same client identifier to multiple
instances of a registered client MUST be very particular about the
circumstances under which this occurs. For instance, the
authorization server can limit a given client identifier to clients
using the same redirect-based flow and the same redirect URIs. An
authorization server SHOULD NOT issue the same client secret to
multiple instances of a registered client, even if they are issued
the same client identifier, or else the client secret could be
leaked, allowing malicious imposters to impersonate a confidential
client.
7. References
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7.1. Normative References
[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),
April 2014.
[JWS] Jones, M., Bradley, J., and N. Sakimura, "JSON Web
Signature (JWS)", draft-ietf-jose-json-web-signature (work
in progress), April 2014.
[JWT] Jones, M., Bradley, J., and N. Sakimura, "JSON Web Token
(JWT)", draft-ietf-oauth-json-web-token (work in
progress), April 2014.
[OAuth.JWT]
Jones, M., Campbell, B., and C. Mortimore, "JSON Web Token
(JWT) Profile for OAuth 2.0 Client Authentication and
Authorization Grants", draft-ietf-oauth-jwt-bearer (work
in progress), April 2014.
[OAuth.SAML2]
Campbell, B., Mortimore, C., and M. Jones, "SAML 2.0
Profile for OAuth 2.0 Client Authentication and
Authorization Grants", draft-ietf-oauth-saml2-bearer (work
in progress), April 2014.
[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.
[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
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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.
[RFC7159] Bray, T., "The JavaScript Object Notation (JSON) Data
Interchange Format", RFC 7159, March 2014.
7.2. Informative References
[OAuth.Registration.Management]
Richer, J., Jones, M., Bradley, J., Machulak, M., and P.
Hunt, "OAuth 2.0 Dynamic Client Registration Management
Protocol", draft-ietf-oauth-dyn-reg-management (work in
progress), May 2014.
Appendix A. Use Cases
This appendix describes different ways that this specification can be
utilized, including describing some of the choices that may need to
be made. Some of the choices are independent and can be used in
combination, whereas some of the choices are interrelated.
A.1. Open versus Protected Dynamic Client Registration
A.1.1. Open Dynamic Client Registration
Authorization servers that support open registration allow
registrations to be made with no initial access token. This allows
all client software to register with the authorization server.
A.1.2. Protected Dynamic Client Registration
Authorization servers that support protected registration require
that an initial access token be used when making registration
requests. While the method by which a client or developer receives
this initial access token and the method by which the authorization
server validates this initial access token are out of scope for this
specification, a common approach is for the developer to use a manual
pre-registration portal at the authorization server that issues an
initial access token to the developer.
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A.2. Registration Without or With Software Statements
A.2.1. Registration Without a Software Statement
When a software statement is not used in the registration request,
the authorization server must be willing to use client metadata
values without them being digitally signed or MACed (and thereby
attested to) by any authority. (Note that this choice is independent
of the Open versus Protected choice, and that an initial access token
is another possible form of attestation.)
A.2.2. Registration With a Software Statement
A software statement can be used in a registration request to provide
attestation by an authority for a set of client metadata values.
This can be useful when the authorization server wants to restrict
registration to client software attested to by a set of authorities
or when it wants to know that multiple registration requests refer to
the same piece of client software.
A.3. Registration by the Client or Developer
A.3.1. Registration by the Client
In some use cases, client software will dynamically register itself
with an authorization server to obtain a client identifier and other
information needed to interact with the authorization server. In
this case, no client identifier for the authorization server is
packaged with the client software.
A.3.2. Registration by the Developer
In some cases, the developer (or development software being used by
the developer) will pre-register the client software with the
authorization server or a set of authorization servers. In this
case, the client identifier value(s) for the authorization server(s)
can be packaged with the client software.
A.4. Client ID per Client Instance or per Client Software
A.4.1. Client ID per Client Software Instance
In some cases, each deployed instance of a piece of client software
will dynamically register and obtain distinct client identifier
values. This can be advantageous, for instance, if the code flow is
being used, as it also enables each client instance to have its own
client secret. This can be useful for native clients, which cannot
maintain the secrecy of a client secret value packaged with the
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software, but which may be able to maintain the secrecy of a per-
instance client secret.
A.4.2. Client ID Shared Among All Instances of Client Software
In some cases, each deployed instance of a piece of client software
will share a common client identifier value. For instance, this is
often the case for in-browser clients using the implicit flow, when
no client secret is involved. Particular authorization servers might
choose, for instance, to maintain a mapping between software
statement values and client identifier values, and return the same
client identifier value for all registration requests for a
particular piece of software. The circumstances under which an
authorization server would do so, and the specific software statement
characteristics required in this case, are beyond the scope of this
specification.
A.5. Stateful or Stateless Registration
A.5.1. Stateful Client Registration
In some cases, authorization servers will maintain state about
registered clients, typically indexing this state using the client
identifier value. This state would typically include the client
metadata values associated with the client registration, and possibly
other state specific to the authorization server's implementation.
When stateful registration is used, operations to support retrieving
and/or updating this state may be supported. One possible set of
operations upon stateful registrations is described in the
[OAuth.Registration.Management] specification.
A.5.2. Stateless Client Registration
In some cases, authorization servers will be implemented in a manner
the enables them to not maintain any local state about registered
clients. One means of doing this is to encode all the registration
state in the returned client identifier value, and possibly
encrypting the state to the authorization server to maintain the
confidentiality and integrity of the state.
Appendix B. 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,
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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 C. Document History
[[ to be removed by the RFC editor before publication as an RFC ]]
-17
o Merged draft-ietf-oauth-dyn-reg-metadata back into this document.
o Removed "Core" from the document title.
o Explicitly state that all metadata members are optional.
o Clarified language around software statements for use in
registration context.
o Clarified that software statements need to be digitally signed or
MACed.
o Added a "jwks" metadata parameter to parallel the "jwks_uri"
parameter.
o Removed normative language from terminology.
o Expanded abstract and introduction.
o Addressed review comments from several working group members.
-16
o Replaced references to draft-jones-oauth-dyn-reg-metadata and
draft-jones-oauth-dyn-reg-management with
draft-ietf-oauth-dyn-reg-metadata and
draft-ietf-oauth-dyn-reg-management.
o Addressed review comments by Phil Hunt and Tony Nadalin.
-15
o Partitioned the Dynamic Client Registration specification into
core, metadata, and management specifications. This built on work
first published as draft-richer-oauth-dyn-reg-core-00 and
draft-richer-oauth-dyn-reg-management-00.
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o Added the ability to use Software Statements. This built on work
first published as draft-hunt-oauth-software-statement-00 and
draft-hunt-oauth-client-association-00.
o Created the IANA OAuth Registration Client Metadata registry for
registering Client Metadata values.
o Defined Client Instance term and stated that multiple instances
can use the same client identifier value under certain
circumstances.
o Rewrote the introduction.
o Rewrote the Use Cases appendix.
-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
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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
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
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o Added example for initial registration credential
-09
o Added method of internationalization for Client Metadata values
o Fixed SAML reference
-08
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.
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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.
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
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-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
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-parameter inputs to endpoint
o Removed pull-based registration
-00
o Imported original UMA draft specification
Authors' Addresses
Justin Richer
The MITRE Corporation
Email: jricher@mitre.org
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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: m.p.machulak@ncl.ac.uk
URI: http://ncl.ac.uk/
Phil Hunt
Oracle Corporation
Email: phil.hunt@yahoo.com
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