draft-ietf-oauth-v2-08.txt   draft-ietf-oauth-v2-09.txt 
Network Working Group E. Hammer-Lahav, Ed. Network Working Group E. Hammer-Lahav, Ed.
Internet-Draft Yahoo! Internet-Draft Yahoo!
Intended status: Standards Track D. Recordon Intended status: Standards Track D. Recordon
Expires: December 17, 2010 Facebook Expires: December 31, 2010 Facebook
D. Hardt D. Hardt
Microsoft Microsoft
June 15, 2010 June 29, 2010
The OAuth 2.0 Protocol The OAuth 2.0 Protocol
draft-ietf-oauth-v2-08 draft-ietf-oauth-v2-09
Abstract Abstract
This specification describes the OAuth 2.0 protocol. This specification describes the OAuth 2.0 protocol.
Status of this Memo Status of this Memo
This Internet-Draft is submitted in full conformance with the This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
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This Internet-Draft will expire on December 17, 2010. This Internet-Draft will expire on December 31, 2010.
Copyright Notice Copyright Notice
Copyright (c) 2010 IETF Trust and the persons identified as the Copyright (c) 2010 IETF Trust and the persons identified as the
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.1. Notational Conventions . . . . . . . . . . . . . . . . . . 3 1.1. Notational Conventions . . . . . . . . . . . . . . . . . . 5
1.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4 1.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 5
1.3. Overview . . . . . . . . . . . . . . . . . . . . . . . . . 5 1.3. Overview . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.4. Client Profiles . . . . . . . . . . . . . . . . . . . . . 8 1.4. Client Profiles . . . . . . . . . . . . . . . . . . . . . 9
1.4.1. Web Server . . . . . . . . . . . . . . . . . . . . . . 8 1.4.1. Web Server . . . . . . . . . . . . . . . . . . . . . . 10
1.4.2. User-Agent . . . . . . . . . . . . . . . . . . . . . . 9 1.4.2. User-Agent . . . . . . . . . . . . . . . . . . . . . . 11
1.4.3. Native Application . . . . . . . . . . . . . . . . . . 11 1.4.3. Native Application . . . . . . . . . . . . . . . . . . 13
1.4.4. Autonomous . . . . . . . . . . . . . . . . . . . . . . 12 1.4.4. Autonomous . . . . . . . . . . . . . . . . . . . . . . 14
2. Client Credentials . . . . . . . . . . . . . . . . . . . . . . 12 2. Client Credentials . . . . . . . . . . . . . . . . . . . . . . 14
2.1. Basic Client Credentials . . . . . . . . . . . . . . . . . 13 2.1. Basic Client Credentials . . . . . . . . . . . . . . . . . 15
3. Obtaining End-User Authorization . . . . . . . . . . . . . . . 14 3. Obtaining End-User Authorization . . . . . . . . . . . . . . . 16
3.1. Authorization Server Response . . . . . . . . . . . . . . 16 3.1. Authorization Response . . . . . . . . . . . . . . . . . . 18
4. Obtaining an Access Token . . . . . . . . . . . . . . . . . . 17 3.2. Error Response . . . . . . . . . . . . . . . . . . . . . . 20
4.1. Access Grant Parameters . . . . . . . . . . . . . . . . . 18 3.2.1. Error Codes . . . . . . . . . . . . . . . . . . . . . 21
4.1.1. Authorization Code . . . . . . . . . . . . . . . . . . 18 4. Obtaining an Access Token . . . . . . . . . . . . . . . . . . 21
4.1.2. Resource Owner Basic Credentials . . . . . . . . . . . 19 4.1. Access Grant Types . . . . . . . . . . . . . . . . . . . . 22
4.1.3. Assertion . . . . . . . . . . . . . . . . . . . . . . 20 4.1.1. Authorization Code . . . . . . . . . . . . . . . . . . 23
4.1.4. Refresh Token . . . . . . . . . . . . . . . . . . . . 20 4.1.2. Resource Owner Basic Credentials . . . . . . . . . . . 23
4.2. Access Token Response . . . . . . . . . . . . . . . . . . 21 4.1.3. Assertion . . . . . . . . . . . . . . . . . . . . . . 24
4.3. Error Response . . . . . . . . . . . . . . . . . . . . . . 22 4.1.4. Refresh Token . . . . . . . . . . . . . . . . . . . . 25
4.3.1. Error Codes . . . . . . . . . . . . . . . . . . . . . 23 4.2. Access Token Response . . . . . . . . . . . . . . . . . . 25
5. Accessing a Protected Resource . . . . . . . . . . . . . . . . 23 4.3. Error Response . . . . . . . . . . . . . . . . . . . . . . 27
5.1. The Authorization Request Header Field . . . . . . . . . . 24 4.3.1. Error Codes . . . . . . . . . . . . . . . . . . . . . 27
5.2. URI Query Parameter . . . . . . . . . . . . . . . . . . . 25 5. Accessing a Protected Resource . . . . . . . . . . . . . . . . 28
5.3. Form-Encoded Body Parameter . . . . . . . . . . . . . . . 25 5.1. Authenticated Requests . . . . . . . . . . . . . . . . . . 29
6. The WWW-Authenticate Response Header Field . . . . . . . . . . 26 5.1.1. The Authorization Request Header Field . . . . . . . . 29
7. Security Considerations . . . . . . . . . . . . . . . . . . . 27 5.1.2. URI Query Parameter . . . . . . . . . . . . . . . . . 29
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 27 5.1.3. Form-Encoded Body Parameter . . . . . . . . . . . . . 30
Appendix A. Examples . . . . . . . . . . . . . . . . . . . . . . 27 5.2. The WWW-Authenticate Response Header Field . . . . . . . . 31
Appendix B. Contributors . . . . . . . . . . . . . . . . . . . . 27 5.2.1. Error Codes . . . . . . . . . . . . . . . . . . . . . 32
Appendix C. Acknowledgements . . . . . . . . . . . . . . . . . . 28 6. Extensibility . . . . . . . . . . . . . . . . . . . . . . . . 33
Appendix D. Document History . . . . . . . . . . . . . . . . . . 28 6.1. Defining New Client Credentials Types . . . . . . . . . . 33
9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 31 6.2. Defining New Endpoint Parameters . . . . . . . . . . . . . 33
9.1. Normative References . . . . . . . . . . . . . . . . . . . 31 6.3. Defining New Header Field Parameters . . . . . . . . . . . 34
9.2. Informative References . . . . . . . . . . . . . . . . . . 32 6.4. Defining New Access Grant Types . . . . . . . . . . . . . 34
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 32 7. Security Considerations . . . . . . . . . . . . . . . . . . . 34
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 34
8.1. The OAuth Parameters Registry . . . . . . . . . . . . . . 34
8.1.1. Registration Template . . . . . . . . . . . . . . . . 35
8.1.2. Example . . . . . . . . . . . . . . . . . . . . . . . 35
Appendix A. Examples . . . . . . . . . . . . . . . . . . . . . . 36
Appendix B. Contributors . . . . . . . . . . . . . . . . . . . . 36
Appendix C. Acknowledgements . . . . . . . . . . . . . . . . . . 36
Appendix D. Document History . . . . . . . . . . . . . . . . . . 36
9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 40
9.1. Normative References . . . . . . . . . . . . . . . . . . . 40
9.2. Informative References . . . . . . . . . . . . . . . . . . 41
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 42
1. Introduction 1. Introduction
With the increasing use of distributed web services and cloud With the increasing use of distributed web services and cloud
computing, third-party applications require access to server-hosted computing, third-party applications require access to server-hosted
resources. These resources are usually protected and require resources. These resources are usually protected and require
authentication using the resource owner's credentials (typically a authentication using the resource owner's credentials (typically a
username and password). In the traditional client-server username and password).
authentication model, a client accessing a protected resource on a
server presents the resource owner's credentials in order to
authenticate and gain access.
OAuth introduces a third role to the traditional client-server In the traditional client-server authentication model, the client
authentication model: the resource owner. In OAuth, the client accesses a protected resource on the server by presenting the
(which is usually not the resource owner, but is acting on its resource owner's credentials in order to authenticate and gain
behalf) requests access to resources controlled by the resource owner access. OAuth introduces a third role to the traditional model: the
and hosted by the resource server. resource owner. In OAuth, the client (which is usually not the
resource owner, but is acting on its behalf) requests access to
resources controlled by the resource owner and hosted by the resource
server.
In addition to removing the need for resource owners to share their In addition to removing the need for resource owners to share their
credentials, resource owners should also have the ability to restrict credentials, resource owners require the ability to restrict access
access to a limited subset of the resources they control, to limit to a limited subset of the resources they control, to limit access
access duration, or to limit access to the methods supported by these duration, or to limit access to the methods supported by these
resources. resources.
Instead of using the resource owner's credentials to access protected Instead of using the resource owner's credentials to access protected
resources, clients obtain an access token (which denotes a specific resources, clients obtain an access token (a string which denotes a
scope, duration, and other attributes). Tokens are issued to third- specific scope, duration, and other attributes). The format and
party client by an authorization server with the approval of the structure of access tokens is beyond the scope of this specification.
resource owner. The client uses the access token to access the
protected resources. Tokens are issued to third-party clients by an authorization server
with the approval of the resource owner. The client uses the access
token to access the protected resources hosted by the resource
server. The interaction between the authorization server and
resource server is beyond the scope of this specification.
For example, a web user (resource owner) can grant a printing service For example, a web user (resource owner) can grant a printing service
(client) access to her protected photos stored at a photo sharing (client) access to her protected photos stored at a photo sharing
service (resource server), without sharing her username and password service (resource server), without sharing her username and password
with the printing service. Instead, she authenticates directly with with the printing service. Instead, she authenticates directly with
the photo sharing service (authorization server) which issues the the photo sharing service (authorization server) which issues the
printing service delegation-specific credentials (token). printing service delegation-specific credentials (token).
This specification defines the use of OAuth over HTTP [RFC2616] (or This specification defines the use of OAuth over HTTP [RFC2616] (or
HTTP over TLS as defined by [RFC2818]). Other specifications may HTTP over TLS as defined by [RFC2818]). Other specifications may
extend it for use with other transport protocols. extend it for use with other transport protocols.
1.1. Notational Conventions 1.1. Notational Conventions
The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL', 'SHALL NOT', The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL', 'SHALL NOT',
'SHOULD', 'SHOULD NOT', 'RECOMMENDED', 'MAY', and 'OPTIONAL' in this 'SHOULD', 'SHOULD NOT', 'RECOMMENDED', 'MAY', and 'OPTIONAL' in this
document are to be interpreted as described in [RFC2119]. document are to be interpreted as described in [RFC2119].
This document uses the Augmented Backus-Naur Form (ABNF) notation of This document uses the Augmented Backus-Naur Form (ABNF) notation of
[I-D.ietf-httpbis-p1-messaging]. Additionally, the following rules
[I-D.ietf-httpbis-p1-messaging]. Additionally, the realm and auth- are included from [RFC2617]: realm, auth-param; from [RFC3986]: URI-
param rules are included from [RFC2617]. Reference; and from [I-D.ietf-httpbis-p1-messaging]: OWS, RWS, and
quoted-string.
Unless otherwise noted, all the protocol parameter names and values Unless otherwise noted, all the protocol parameter names and values
are case sensitive. are case sensitive.
1.2. Terminology 1.2. Terminology
protected resource protected resource
An access-restricted resource which can be obtained using an An access-restricted resource which can be obtained using an
OAuth-authenticated request. OAuth-authenticated request.
skipping to change at page 4, line 47 skipping to change at page 6, line 11
and other authorization attributes granted by the resource and other authorization attributes granted by the resource
owner and enforced by the resource server and authorization owner and enforced by the resource server and authorization
servers. servers.
access token access token
A token used by the client to make authenticated requests A token used by the client to make authenticated requests
on behalf of the resource owner. on behalf of the resource owner.
refresh token refresh token
A token used by the client to obtain a new access token A token used by the client to obtain a new access token
(in addition or as a replacement for an expired access without having to involve the resource owner.
token), without having to involve the resource owner.
authorization code A short-lived token representing the access authorization code A short-lived token representing the access
grant provided by the end-user. The authorization code grant provided by the end-user. The authorization code
is used to obtain an access token and a refresh token. is used to obtain an access token and a refresh token.
authorization server authorization server
A server capable of issuing tokens after successfully A server capable of issuing tokens after successfully
authenticating the resource owner and obtaining authorization. authenticating the resource owner and obtaining authorization.
The authorization server may be the same server as the resource The authorization server may be the same server as the resource
server, or a separate entity. server, or a separate entity.
skipping to change at page 5, line 36 skipping to change at page 6, line 44
An unique identifier issued to the client to identify itself to An unique identifier issued to the client to identify itself to
the authorization server. Client identifiers may have a the authorization server. Client identifiers may have a
matching secret. The client identifier is described in matching secret. The client identifier is described in
Section 2. Section 2.
1.3. Overview 1.3. Overview
OAuth provides a method for clients to access a protected resource on OAuth provides a method for clients to access a protected resource on
behalf of a resource owner. Before a client can access a protected behalf of a resource owner. Before a client can access a protected
resource, it must first obtain authorization from the resource owner, resource, it must first obtain authorization from the resource owner,
then exchange that access grant for an access token (representing the then exchange the access grant for an access token (representing the
grant's scope, duration, and other attributes). The client accesses grant's scope, duration, and other attributes). The client accesses
the protected resource by presenting the access token to the resource the protected resource by presenting the access token to the resource
server. server.
+--------+ +---------------+ +--------+ +---------------+
| |--(A)-- Authorization Request --->| Resource | | |--(A)-- Authorization Request --->| Resource |
| | | Owner | | | | Owner |
| |<-(B)------ Access Grant ---------| | | |<-(B)------ Access Grant ---------| |
| | +---------------+ | | +---------------+
| | | |
skipping to change at page 6, line 30 skipping to change at page 7, line 30
| |<-(F)---- Protected Resource -----| | | |<-(F)---- Protected Resource -----| |
+--------+ +---------------+ +--------+ +---------------+
Figure 1: Abstract Protocol Flow Figure 1: Abstract Protocol Flow
The abstract flow illustrated in Figure 1 includes the following The abstract flow illustrated in Figure 1 includes the following
steps: steps:
(A) The client requests authorization from the resource owner. The (A) The client requests authorization from the resource owner. The
client should not interact directly with the resource owner client should not interact directly with the resource owner
(since that would exposing the resource owner's credentials to (since that would expose the resource owner's credentials to the
the client), but instead requests authorization via an client), but instead request authorization via an authorization
authorization server or other entities. For example, the client server or other entities. For example, the client directs the
directs the resource owner to the authorization server which in resource owner to the authorization server which in turn issues
turn issues it an access grant. When cannot be avoided, the it an access grant. When unavoidable, the client interacts
client interacts directly with the end-user, asking for the end- directly with the end-user, asking for the end-user's username
user's username and password. and password. If the client is acting autonomously, the
authorization request is beyond the scope of this specification.
(B) The client is issued an access grant which represents the (B) The client is issued an access grant which represents the
authorization provided by the resource owner. The access grant authorization provided by the resource owner. The access grant
can be expressed as: can be expressed as:
* Authorization code - an access grant obtained via an * Authorization code - an access grant obtained via an
authorization server. The process used to obtain an authorization server. The process used to obtain an
authorization code is described in Section 3. authorization code utilized the end-user's user-agent and is
described in Section 3.
* Assertion - an access grant obtained from entities using a * Assertion - an access grant obtained using a different trust
different trust framework. Assertions enable the client to framework. Assertions enable the client to utilize existing
utilize existing trust relationships to obtain an access trust relationships to obtain an access token. They provide
token. They provide a bridge between OAuth and other trust a bridge between OAuth and other trust frameworks. The
frameworks. The access grant represented by an assertion access grant represented by an assertion depends on the
depends on the assertion type, its content, and how it was assertion type, its content, and how it was issued, which are
issued, which are beyond the scope of this specification. beyond the scope of this specification.
* Basic end-user credentials - obtained when interacting * Resource owner basic credentials - obtained when interacting
directly with an end-user. Resource owner credentials should directly with a resource-owner. Resource owner basic
only be used when there is a high degree of trust between the credentials (i.e. a username and password) should only be
resource owner the client (e.g. its computer operating system used when there is a high degree of trust between the
or a highly privileged application). However, unlike the resource owner and the client (e.g. its computer operating
HTTP Basic authentication scheme defined in [RFC2617], the system or a highly privileged application). However, unlike
end-user's credentials are used in a single request and are the HTTP Basic authentication scheme defined in [RFC2617],
exchanged for an access token and refresh token which the resource owner's credentials are used for a single
eliminates the client need to store them for future use. request and are exchanged for an access token and refresh
token. This eliminates the need for the client to store the
resource-owner's credentials for future use.
(C) The client requests an access token by authenticating with the (C) The client requests an access token by authenticating with the
authorization server, and presenting the access grant. The authorization server, and presenting the access grant. The
token request is described in Section 4. token request is described in Section 4.
(D) The authorization server validated the client credentials and (D) The authorization server validates the client credentials and
the access grant, and issues an access token with an optional the access grant, and issues an access token with an optional
refresh token. Access token usually have a shorter lifetime refresh token. Access tokens usually have a shorter lifetime
than the access grant. Refresh tokens usually have a lifetime than the access grant. Refresh tokens usually have a lifetime
equal to the duration of the access grant. When an access token equal to the duration of the access grant. When an access token
expires, the refresh token is used to obtain a new access token expires, the refresh token is used to obtain a new access token
without having to request another access grant from the resource without having to request another access grant from the resource
owner (in which case, the refresh token acts as an access owner.
grant).
(E) The client makes a protect resource request to the resource (E) The client makes a protected resource request to the resource
server, and presents the access token in order to gain access. server, and presents the access token in order to gain access.
Accessing a protected resource is described in Section 5. Accessing a protected resource is described in Section 5.
(F) The resource server validates the access token, and if valid, (F) The resource server validates the access token, and if valid,
serves the request. serves the request.
When the client is acting on behalf of itself (the client is also the When the client is acting on its own behalf (the client is also the
resource owner), the client skips steps (A) and (B), and does not resource owner), the client does not obtain an access grant. The
include an access grant in step (C). When the client uses the user- simplified protocol flow is illustrated in Figure 2:
agent profile (described in Section 1.4.2), the authorization request
(A) results in an access token (D), skipping steps (B) and (C).
The sizes of tokens and other values received from the authorization +--------+ +---------------+
server, are left undefined by this specification. Clients should | |--(C)--- Client Credentials ----->| Authorization |
avoid making assumptions about value sizes. Servers should document | | | Server |
the expected size of any value they issue. | |<-(D)------ Access Token ---------| |
| | (w/ Optional Refresh Token) +---------------+
| Client |
| | +---------------+
| |--(E)------ Access Token -------->| Resource |
| | | Server |
| |<-(F)---- Protected Resource -----| |
+--------+ +---------------+
Figure 2: Protocol Flow for Client Acting On Its Own Behalf
When the client uses the user-agent profile (described in
Section 1.4.2), the authorization request results in an access token,
as illustrated in Figure 3:
+--------+ +----------+ +---------------+
| |--(A)-- Authorization --+- -+-->| |
| | Request | Resource | | Authorization |
| | | Owner | | Server |
| |<-(D)-- Access Token ---+- -+---| |
| | +----------+ +---------------+
| Client |
| | +---------------+
| |--(E)-------- Access Token ----------->| Resource |
| | | Server |
| |<-(F)------ Protected Resource --------| |
+--------+ +---------------+
Figure 3: Indirect Access Grant Protocol Flow
1.4. Client Profiles 1.4. Client Profiles
OAuth supports a wide range of client types by providing a rich and OAuth supports a wide range of client types by providing a rich and
extensible framework for establishing authorization and exchaning it extensible framework for establishing authorization and exchanging it
for an access token. The methods detailed in this specification were for an access token. The methods detailed in this specification were
designed to accomodate four client types: web servers, user-agents, designed to accommodate four client types: web servers, user-agents,
native applications, and autonomous clients. Additional native applications, and autonomous clients. Additional
authorization flows and client profiles may be defined by other authorization flows and client profiles may be defined by other
specifications to cover additional scenarios and client types. specifications to cover additional scenarios and client types.
1.4.1. Web Server 1.4.1. Web Server
The web server profile is suitable for clients capable of interacting The web server profile is suitable for clients capable of interacting
with the end-user's user-agent (typically a web browser) and capable with the end-user's user-agent (typically a web browser) and capable
of receiving incoming requests from the authorization server (capable of receiving incoming requests from the authorization server (capable
of acting as an HTTP server). of acting as an HTTP server).
skipping to change at page 8, line 41 skipping to change at page 10, line 31
| | | | | | | |
^ v | | ^ v | |
+---------+ | | +---------+ | |
| |>---(D)-- Client Credentials, --------' | | |>---(D)-- Client Credentials, --------' |
| Web | Authorization Code, | | Web | Authorization Code, |
| Client | & Redirect URI | | Client | & Redirect URI |
| | | | | |
| |<---(E)----- Access Token -------------------' | |<---(E)----- Access Token -------------------'
+---------+ (w/ Optional Refresh Token) +---------+ (w/ Optional Refresh Token)
Figure 2: Web Server Flow Figure 4: Web Server Flow
The web server flow illustrated in Figure 2 includes the following The web server flow illustrated in Figure 4 includes the following
steps: steps:
(A) The web client initiates the flow by redirecting the end-user's (A) The web client initiates the flow by redirecting the end-user's
user-agent to the end-user authorization endpoint as described user-agent to the end-user authorization endpoint as described
in Section 3 using client type "web_server". The client in Section 3 The client includes its client identifier,
includes its client identifier, requested scope, local state, requested scope, local state, and a redirect URI to which the
and a redirect URI to which the authorization server will send authorization server will send the end-user back once access is
the end-user back once access is granted (or denied). granted (or denied).
(B) The authorization server authenticates the end-user (via the (B) The authorization server authenticates the end-user (via the
user-agent) and establishes whether the end-user grants or user-agent) and establishes whether the end-user grants or
denies the client's access request. denies the client's access request.
(C) Assuming the end-user granted access, the authorization server (C) Assuming the end-user granted access, the authorization server
redirects the user-agent back to the client to the redirection redirects the user-agent back to the client to the redirection
URI provided earlier. The authorization includes an URI provided earlier. The authorization includes an
authorization code for the client to use to obtain an access authorization code for the client to use to obtain an access
token. token.
skipping to change at page 10, line 12 skipping to change at page 12, line 12
to the end-user and other applications residing on the computer or to the end-user and other applications residing on the computer or
device. device.
+----------+ Client Identifier +----------------+ +----------+ Client Identifier +----------------+
| |>---(A)-- & Redirection URI --->| | | |>---(A)-- & Redirection URI --->| |
| | | | | | | |
End <--+ - - - +----(B)-- User authenticates -->| Authorization | End <--+ - - - +----(B)-- User authenticates -->| Authorization |
User | | | Server | User | | | Server |
| |<---(C)--- Redirect URI -------<| | | |<---(C)--- Redirect URI -------<| |
| Client | with Access Token | | | Client | with Access Token | |
| in | (w/ Optional Authorization +----------------+ | in | in Fragment +----------------+
| Browser | Code) in Fragment | Browser |
| | +----------------+ | | +----------------+
| |>---(D)--- Redirect URI ------->| | | |>---(D)--- Redirect URI ------->| |
| | without Fragment | Web Server | | | without Fragment | Web Server |
| | | with Client | | | | with Client |
| (F) |<---(E)--- Web Page with ------<| Resource | | (F) |<---(E)--- Web Page with ------<| Resource |
| Access | Script | | | Access | Script | |
| Token | +----------------+ | Token | +----------------+
+----------+ +----------+
Figure 3: User-Agent Flow Figure 5: User-Agent Flow
The user-agent flow illustrated in Figure 3 includes the following The user-agent flow illustrated in Figure 5 includes the following
steps: steps:
(A) The client sends the user-agent to the end-user authorization (A) The client sends the user-agent to the end-user authorization
endpoint as described in Section 3 using client type endpoint as described in Section 3. The client includes its
"user-agent". The client includes its client identifier, client identifier, requested scope, local state, and a redirect
requested scope, local state, and a redirect URI to which the URI to which the authorization server will send the end-user
authorization server will send the end-user back once back once authorization is granted (or denied).
authorization is granted (or denied).
(B) The authorization server authenticates the end-user (via the (B) The authorization server authenticates the end-user (via the
user-agent) and establishes whether the end-user grants or user-agent) and establishes whether the end-user grants or
denies the client's access request. denies the client's access request.
(C) If the end-user granted access, the authorization server (C) If the end-user granted access, the authorization server
redirects the user-agent to the redirection URI provided redirects the user-agent to the redirection URI provided
earlier. The redirection URI includes the access token (and an earlier. The redirection URI includes the access token in the
optional authorization code) in the URI fragment. URI fragment.
(D) The user-agent follows the redirection instructions by making a (D) The user-agent follows the redirection instructions by making a
request to the web server which does not include the fragment. request to the web server which does not include the fragment.
The user-agent retains the fragment information locally. The user-agent retains the fragment information locally.
(E) The web server returns a web page (typically an HTML page with (E) The web server returns a web page (typically an HTML page with
an embedded script) capable of accessing the full redirection an embedded script) capable of accessing the full redirection
URI including the fragment retained by the user-agent, and URI including the fragment retained by the user-agent, and
extracting the access token (and other parameters) contained in extracting the access token (and other parameters) contained in
the fragment. the fragment.
(F) The user-agent executes the script provided by the web server (F) The user-agent executes the script provided by the web server
which extracts the access token and passes it to the client. If locally, which extracts the access token and passes it to the
an authorization code was issued, the client can pass it to a client.
web server component to obtain another access token for
additional server-based protected resources interaction.
1.4.3. Native Application 1.4.3. Native Application
Native application are clients running as native code on the end- Native application are clients running as native code on the end-
user's computer or device (i.e. executing outside a user-agent or as user's computer or device (i.e. executing outside a user-agent or as
a desktop program). These clients are often capable of interacting a desktop program). These clients are often capable of interacting
with (or embedding) the end-user's user-agent but are incapable of with (or embedding) the end-user's user-agent but are limited in how
receiving callback requests from the server (incapable of acting as such interaction affects their end-user experience. In many cases,
an HTTP server). native applications are incapable of receiving direct callback
requests from the server (e.g. firewall, operating system
restrictions).
Native application clients can be implemented in different ways based Native application clients can be implemented in different ways based
on their requirements and desired end-user experience. Native on their requirements and desired end-user experience. Native
application clients can: application clients can:
o Utilize the end-user authorization endpoint as described in o Utilize the end-user authorization endpoint as described in
Section 3 by launching an external user-agent. The client can Section 3 by launching an external user-agent. The client can
capture the response by providing a redirection URI with a custom capture the response by providing a redirection URI with a custom
URI scheme (registered with the operating system to invoke the URI scheme (registered with the operating system to invoke the
client application), or by providing a redirection URI pointing to client application), or by providing a redirection URI pointing to
a server-hosted resource under the client's control which puts the a server-hosted resource under the client's control which makes
response in the user-agent window title (from which the client can the response available to the client (e.g. using the window title
obtain the response by polling the user-agnet window, looking for or other locations accessible from outside the user-agent).
a window title change).
o Utilize the end-user authorization endpoint as described in o Utilize the end-user authorization endpoint as described in
Section 3 by using an embedded user-agent. The client obtains the Section 3 by using an embedded user-agent. The client obtains the
response by directly communicating with the embedded user-agent. response by directly communicating with the embedded user-agent.
o Prompt end-users for their basic credentials (username and o Prompt end-users for their basic credentials (username and
password) and use them directly to obtain an access token. This password) and use them directly to obtain an access token. This
is generally discouraged as it hands the end-user's password is generally discouraged as it hands the end-user's password
directly to the 3rd party and is limited to basic credentials. directly to the 3rd party and is limited to basic credentials.
When choosing between launching an external browser and an embedded When choosing between launching an external browser and an embedded
user-agent, developers should consider the following: user-agent, developers should consider the following:
o External user-agents may improve completion rate as the end-user o External user-agents may improve completion rate as the end-user
may already be logged-in and not have to re-authenticate. may already be logged-in and not have to re-authenticate.
o Embedded user-agents often offer a better end-user flow, as they o Embedded user-agents often offer a better end-user flow, as they
remove the need to switch context and open new windows. remove the need to switch context and open new windows.
o Embedded user-agents are less secure because users are o Embedded user-agents pose a security challenge because users are
authenticating in unidentified window without access to the authenticating in an unidentified window without access to the
protections offered by many user-agents. visual protections offered by many user-agents.
1.4.4. Autonomous 1.4.4. Autonomous
Autonomous clients act on their own behalf (the client is also the Autonomous clients utilize an existing trust relationship or
resource owner), or utilize existing trust relationship or framework framework to establish authorization. Autonomous clients can be
to establish authorization without directly involving the resource implemented in different ways based on their requirements and the
owner. existing trust framework they rely upon. Autonomous clients can:
Autonomous clients can be implemented in different ways based on
their requirements and the existing trust framework they rely upon.
Autonomous clients can:
o Obtain an access token by authenticating with the authorization o Obtain an access token by authenticating with the authorization
server using their client credentials. The scope of the access server using their client credentials. The scope of the access
token is limited to the protected resources under the control of token is limited to the protected resources under the control of
the client. the client, or that of another resource owner previously arranged
with the authorization server.
o Use an existing access grant expressed as an assertion using an o Use an existing access grant expressed as an assertion using an
assertion format supported by the authorization server. Using assertion format supported by the authorization server. Using
assertions requires the client to obtain a assertion (such as a assertions requires the client to obtain a assertion (such as a
SAML [OASIS.saml-core-2.0-os] assertion) from an assertion issuer SAML [OASIS.saml-core-2.0-os] assertion) from an assertion issuer
or to self-issue an assertion. The assertion format, the process or to self-issue an assertion. The assertion format, the process
by which the assertion is obtained, and the method of validating by which the assertion is obtained, and the method of validating
the assertion are defined by the assertion issuer and the the assertion are defined by the assertion issuer and the
authorization server, and are beyond the scope of this authorization server, and are beyond the scope of this
specification. specification.
skipping to change at page 13, line 5 skipping to change at page 14, line 47
the scope of this specification, but usually involve registration the scope of this specification, but usually involve registration
with the authorization server. [[ OAuth Discovery provides one way of with the authorization server. [[ OAuth Discovery provides one way of
obtaining basic client credentials ]] obtaining basic client credentials ]]
Due to the nature of some clients, authorization servers SHOULD NOT Due to the nature of some clients, authorization servers SHOULD NOT
make assumptions about the confidentiality of client credentials make assumptions about the confidentiality of client credentials
without establishing trust with the client operator. Authorization without establishing trust with the client operator. Authorization
servers SHOULD NOT issue client secrets to clients incapable of servers SHOULD NOT issue client secrets to clients incapable of
keeping their secrets confidential. keeping their secrets confidential.
This specification provides one mean of authenticating the client This specification provides one mechanism for authenticating the
using a set of basic client credentials. The authorization server client using a set of basic client credentials. The authorization
MAY authenticate the client using any desired authentication scheme. server MAY authenticate the client using any desired authentication
scheme.
The client MUST NOT include more than one set of client credentials
with each request, and MUST NOT utilize more than one mechanism to
authenticate each request (regardless whether the credentials are
identical).
2.1. Basic Client Credentials 2.1. Basic Client Credentials
The basic client credentials include a client identifier and an The basic client credentials include a client identifier and an
OPTIONAL matching shared symmetric secret. The client identifier and OPTIONAL matching shared symmetric secret. The client identifier and
secret are included in the request using the HTTP Basic secret are included in the request using the HTTP Basic
authentication scheme as defined in [RFC2617] by including the client authentication scheme as defined in [RFC2617] by including the client
identifier as the username and secret as the password. identifier as the username and secret as the password.
For example (line breaks are for display purposes only): For example (line breaks are for display purposes only):
POST /token HTTP/1.1 POST /token HTTP/1.1
Host: server.example.com Host: server.example.com
Authorization: Basic czZCaGRSa3F0MzpnWDFmQmF0M2JW Authorization: Basic czZCaGRSa3F0MzpnWDFmQmF0M2JW
Content-Type: application/x-www-form-urlencoded Content-Type: application/x-www-form-urlencoded
type=web_server&code=i1WsRn1uB1& type=web-server&code=i1WsRn1uB1&
redirect_uri=https%3A%2F%2Fclient%2Eexample%2Ecom%2Fcb redirect_uri=https%3A%2F%2Fclient%2Eexample%2Ecom%2Fcb
Alternatively, the client MAY include the credentials using the Alternatively, the client MAY include the credentials using the
following request parameters: following request parameters:
client_id client_id
REQUIRED. The client identifier. REQUIRED. The client identifier.
client_secret REQUIRED if the client identifier has a matching client_secret REQUIRED if the client identifier has a matching
secret. secret.
For example (line breaks are for display purposes only): For example (line breaks are for display purposes only):
POST /token HTTP/1.1 POST /token HTTP/1.1
Host: server.example.com Host: server.example.com
Content-Type: application/x-www-form-urlencoded Content-Type: application/x-www-form-urlencoded
type=web_server&client_id=s6BhdRkqt3& type=web-server&client_id=s6BhdRkqt3&
client_secret=gX1fBat3bV&code=i1WsRn1uB1& client_secret=gX1fBat3bV&code=i1WsRn1uB1&
redirect_uri=https%3A%2F%2Fclient%2Eexample%2Ecom%2Fcb redirect_uri=https%3A%2F%2Fclient%2Eexample%2Ecom%2Fcb
The client MAY include the client credentials using other HTTP
authentication schemes which support authenticating using a username
and password. The client MUST NOT include the client credentials
using more than one mechanism. If more than one mechanism is used,
regardless whether the credentials are identical or valid, the server
MUST reply with an HTTP 400 status code (Bad Request) and include the
"multiple_credentials" error code.
The authorization server MUST accept the client credentials using The authorization server MUST accept the client credentials using
both the request parameters, and the HTTP Basic authentication both the request parameters, and the HTTP Basic authentication
scheme. The authorization server MAY support additional scheme. The authorization server MAY support additional
authentication schemes. authentication schemes suitable for the transmission of a username
and password.
3. Obtaining End-User Authorization 3. Obtaining End-User Authorization
When the client interacts with an end-user, the end-user MUST first When the client interacts with an end-user, the end-user MUST first
grant the client authorization to access its protected resources. grant the client authorization to access its protected resources.
Once obtained, the end-user access grant is expressed as an Once obtained, the end-user access grant is expressed as an
authorization code which the client uses to obtain an access token. authorization code which the client uses to obtain an access token.
To obtain an end-user authorization, the client sends the end-user to To obtain an end-user authorization, the client sends the end-user to
the end-user authorization endpoint. the end-user authorization endpoint.
skipping to change at page 14, line 41 skipping to change at page 16, line 35
The location of the end-user authorization endpoint can be found in The location of the end-user authorization endpoint can be found in
the service documentation, or can be obtained by using [[ OAuth the service documentation, or can be obtained by using [[ OAuth
Discovery ]]. The end-user authorization endpoint URI MAY include a Discovery ]]. The end-user authorization endpoint URI MAY include a
query component as defined by [RFC3986] section 3, which must be query component as defined by [RFC3986] section 3, which must be
retained when adding additional query parameters. retained when adding additional query parameters.
Since requests to the end-user authorization endpoint result in user Since requests to the end-user authorization endpoint result in user
authentication and the transmission of sensitive information, the authentication and the transmission of sensitive information, the
authorization server SHOULD require the use of a transport-layer authorization server SHOULD require the use of a transport-layer
mechanism such as TLS when sending requests to the end-user security mechanism such as TLS when sending requests to the end-user
authorization endpoint. authorization endpoint.
In order to direct the end-user's user-agent to the authorization In order to direct the end-user's user-agent to the authorization
server, the client constructs the request URI by adding the following server, the client constructs the request URI by adding the following
parameters to the end-user authorization endpoint URI query component parameters to the end-user authorization endpoint URI query component
using the "application/x-www-form-urlencoded" format as defined by using the "application/x-www-form-urlencoded" format as defined by
[W3C.REC-html401-19991224]: [W3C.REC-html401-19991224]:
type response_type
REQUIRED. The client type (user-agent or web server). REQUIRED. The requested response: an access token, an
Determines how the authorization server delivers the authorization code, or both. The parameter value MUST be set
authorization response back to the client. The parameter value to "token" for requesting an access token, "code" for
MUST be set to "web_server" or "user_agent". requesting an authorization code, or "code-and-token" to
request both. The authorization server MAY decline to provide
one or more of these response types. [[ The 'code-and-token'
type is pending use cases and may be removed for the
specification ]]
client_id client_id
REQUIRED. The client identifier as described in Section 2. REQUIRED. The client identifier as described in Section 2.
redirect_uri redirect_uri
REQUIRED, unless a redirection URI has been established between REQUIRED, unless a redirection URI has been established between
the client and authorization server via other means. An the client and authorization server via other means. An
absolute URI to which the authorization server will redirect absolute URI to which the authorization server will redirect
the user-agent to when the end-user authorization step is the user-agent to when the end-user authorization step is
completed. The authorization server SHOULD require the client completed. The authorization server SHOULD require the client
to pre-register their redirection URI. Authorization servers to pre-register their redirection URI.
MAY restrict the redirection URI to not include a query
component as defined by [RFC3986] section 3.
state
OPTIONAL. An opaque value used by the client to maintain state
between the request and callback. The authorization server
includes this value when redirecting the user-agent back to the
client.
scope scope
OPTIONAL. The scope of the access request expressed as a list OPTIONAL. The scope of the access request expressed as a list
of space-delimited strings. The value of the "scope" parameter of space-delimited strings. The value of the "scope" parameter
is defined by the authorization server. If the value contains is defined by the authorization server. If the value contains
multiple space-delimited strings, their order does not matter, multiple space-delimited strings, their order does not matter,
and each string adds an additional access range to the and each string adds an additional access range to the
requested scope. requested scope.
state
OPTIONAL. An opaque value used by the client to maintain state
between the request and callback. The authorization server
includes this value when redirecting the user-agent back to the
client.
The client directs the end-user to the constructed URI using an HTTP The client directs the end-user to the constructed URI using an HTTP
redirection response, or by other means available to it via the end- redirection response, or by other means available to it via the end-
user's user-agent. The request MUST use the HTTP "GET" method. user's user-agent. The request MUST use the HTTP "GET" method.
For example, the client directs the end-user's user-agent to make the For example, the client directs the end-user's user-agent to make the
following HTTPS request (line breaks are for display purposes only): following HTTP request using transport-layer security (line breaks
are for display purposes only):
GET /authorize?type=web_server&client_id=s6BhdRkqt3&redirect_uri= GET /authorize?response_type=code&client_id=s6BhdRkqt3&
https%3A%2F%2Fclient%2Eexample%2Ecom%2Fcb HTTP/1.1 redirect_uri=https%3A%2F%2Fclient%2Eexample%2Ecom%2Fcb HTTP/1.1
Host: server.example.com Host: server.example.com
If the client has previously registered a redirection URI with the If the client has previously registered a redirection URI with the
authorization server, the authorization server MUST verify that the authorization server, the authorization server MUST verify that the
redirection URI received matches the registered URI associated with redirection URI received matches the registered URI associated with
the client identifier. [[ provide guidance on how to perform matching the client identifier. [[ provide guidance on how to perform matching
]] ]]
Parameters sent without a value MUST be treated as if they were
omitted from the request.
The authorization server validates the request to ensure all required
parameters are present and valid. If the request is invalid, the
authorization server immediately redirects the user-agent back to the
client using the redirection URI provided with the appropriate error
code as described in Section 3.2.
The authorization server authenticates the end-user and obtains an The authorization server authenticates the end-user and obtains an
authorization decision (by asking the end-user or by establishing authorization decision (by asking the end-user or by establishing
approval via other means). When a decision has been established, the approval via other means). When a decision has been established, the
authorization server directs the end-user's user-agent to the authorization server directs the end-user's user-agent to the
provided client redirection URI using an HTTP redirection response, provided client redirection URI using an HTTP redirection response,
or by other means available to it via the end-user's user-agent. or by other means available to it via the end-user's user-agent.
3.1. Authorization Server Response 3.1. Authorization Response
If the end-user grants the access request, the authorization server If the end-user grants the access request, the authorization server
issues an access token, an authorization code, or both, and delivers issues an access token, an authorization code, or both, and delivers
them to the client by adding the following parameters to the them to the client by adding the following parameters to the
redirection URI: redirection URI (as described below):
code code
REQUIRED if the client type is "web_server", otherwise REQUIRED if the response type is "token" or "code-and-token",
OPTIONAL. The authorization code generated by the otherwise MUST NOT be included. The authorization code
authorization server. The authorization code SHOULD expire generated by the authorization server. The authorization code
shortly after it is issued and allowed for a single use. The SHOULD expire shortly after it is issued. The authorization
authorization code is bound to the client identifier and server MUST invalidate the authorization code after a single
redirection URI. usage. The authorization code is bound to the client
identifier and redirection URI.
access_token access_token
REQUIRED if the client type is "user_agent", otherwise MUST NOT REQUIRED if the response type is "token" or "code-and-token",
be included. The access token. otherwise MUST NOT be included. The access token.
expires_in expires_in
OPTIONAL. The duration in seconds of the access token lifetime OPTIONAL. The duration in seconds of the access token lifetime
if an access token is included. if an access token is included. For example, the value "3600"
denotes that the access token will expire in one hour from the
state time the response was generated by the authorization server.
REQUIRED if the "state" parameter was present in the client
authorization request. Set to the exact value received from
the client.
If the end-user denies the access request, the authorization server
informs the client by adding the following parameters to the
redirection URI:
error scope
REQUIRED. The parameter value MUST be set to "user_denied". OPTIONAL. The scope of the access token as a list of space-
delimited strings if an access token is included. The value of
the "scope" parameter is defined by the authorization server.
If the value contains multiple space-delimited strings, their
order does not matter, and each string adds an additional
access range to the requested scope.
state state
REQUIRED if the "state" parameter was present in the client REQUIRED if the "state" parameter was present in the client
authorization request. Set to the exact value received from authorization request. Set to the exact value received from
the client. the client.
The method in which the authorization server adds the parameter to The method in which the authorization server adds the parameter to
the redirection URI is determined by the client type provided by the the redirection URI is determined by the response type requested by
client in the authorization request using the "type" parameter. the client in the authorization request using the "response_type"
parameter.
If the client type is "web_server", the authorization server adds the If the response type is "code", the authorization server adds the
parameters to the redirection URI query component using the parameters to the redirection URI query component using the
"application/x-www-form-urlencoded" format as defined by "application/x-www-form-urlencoded" format as defined by
[W3C.REC-html401-19991224]. [W3C.REC-html401-19991224].
For example, the authorization server redirects the end-user's user- For example, the authorization server redirects the end-user's user-
agent by sending the following HTTP response: agent by sending the following HTTP response:
HTTP/1.1 302 Found HTTP/1.1 302 Found
Location: https://client.example.com/cb?code=i1WsRn1uB1 Location: https://client.example.com/cb?code=i1WsRn1uB1
If the client type is "user_agent", the authorization server adds the If the response type is "token", the authorization server adds the
parameters to the redirection URI fragment component using the parameters to the redirection URI fragment component using the
"application/x-www-form-urlencoded" format as defined by "application/x-www-form-urlencoded" format as defined by
[W3C.REC-html401-19991224]. [[ replace form-encoded with JSON? ]] [W3C.REC-html401-19991224].
For example, the authorization server redirects the end-user's user- For example, the authorization server redirects the end-user's user-
agent by sending the following HTTP response: agent by sending the following HTTP response:
HTTP/1.1 302 Found HTTP/1.1 302 Found
Location: http://example.com/rd#access_token=FJQbwq9&expires_in=3600 Location: http://example.com/rd#access_token=FJQbwq9&expires_in=3600
If the response type is "code-and-token", the authorization server
adds the "code" and "state" parameters to the redirection URI query
component and the "access_token", "scope", and "expires_in" to the
redirection URI fragment using the
"application/x-www-form-urlencoded" format as defined by
[W3C.REC-html401-19991224].
For example, the authorization server redirects the end-user's user-
agent by sending the following HTTP response (line breaks are for
display purposes only):
HTTP/1.1 302 Found
Location: http://example.com/rd?code=i1WsRn1uB1
#access_token=FJQbwq9&expires_in=3600
The sizes of tokens and other values received from the authorization
server, are left undefined by this specification. Clients should
avoid making assumptions about value sizes. Servers should document
the expected size of any value they issue.
3.2. Error Response
If the end-user denies the access request or if the request is
invalid, the authorization server informs the client by adding the
following parameters to the redirection URI query component using the
"application/x-www-form-urlencoded" format as defined by
[W3C.REC-html401-19991224]:
error
REQUIRED. A single error code as described in Section 3.2.1.
error_description OPTIONAL. A human-readable text providing
additional information, used to assist in the understanding and
resolution of the error occurred.
error_uri OPTIONAL. A URI identifying a human-readable web page
with information about the error, used to provide the end-user
with additional information about the error.
state
REQUIRED if the "state" parameter was present in the client
authorization request. Set to the exact value received from
the client.
For example, the authorization server redirects the end-user's user-
agent by sending the following HTTP response:
HTTP/1.1 302 Found
Location: https://client.example.com/cb?error=access-denied
3.2.1. Error Codes
The authorization server includes one of the following error codes
with the error response:
invalid-request
The request is missing a required parameter, includes an
unknown parameter or parameter value, or is otherwise
malformed.
invalid-client-id
The client identifier provided is invalid.
unauthorized-client
The client is not authorized to use the requested response
type.
redirect-uri-mismatch
The redirection URI provided does not match a pre-registered
value.
access-denied
The end-user or authorization server denied the request.
unsupported-response-type
The requested response type is not supported by the
authorization server.
invalid_scope
The requested scope is invalid, unknown, or malformed.
[[ Add mechanism for extending error codes ]]
4. Obtaining an Access Token 4. Obtaining an Access Token
The client obtains an access token by authenticating with the The client obtains an access token by authenticating with the
authorization server and presenting its access grant. authorization server and presenting its access grant.
After obtaining authorization from the resource owner, clients After establishing resource owner authorization, clients request an
request an access token from the authorization server's token access token from the authorization server's token endpoint. When
endpoint. When requesting an access token, the client authenticates requesting an access token, the client authenticates with the
with the authorization server and includes the access grant (in the authorization server and includes the access grant (in the form of an
form of an authorization code, resource owner credentials, an authorization code, resource owner credentials, an assertion, or a
assertion, or a refresh token). refresh token).
The location of the token endpoint can be found in the service The location of the token endpoint can be found in the service
documentation, or can be obtained by using [[ OAuth Discovery ]]. documentation, or can be obtained by using [[ OAuth Discovery ]].
The token endpoint URI MAY include a query component, which must be
retained when adding additional query parameters. The token endpoint URI MAY include a query component.
Since requests to the token endpoint result in the transmission of Since requests to the token endpoint result in the transmission of
plain text credentials in the HTTP request and response, the plain text credentials in the HTTP request and response, the
authorization server MUST require the use of a transport-layer authorization server MUST require the use of a transport-layer
mechanism when sending requests to the token endpoints. Servers MUST security mechanism when sending requests to the token endpoints.
support TLS 1.2 as defined in [RFC5246] and MAY support addition Servers MUST support TLS 1.2 as defined in [RFC5246], and MAY support
mechanisms with equivalent protections. additional transport-layer security mechanisms.
The client requests an access token by constructing a token request The client requests an access token by constructing a token request
and making an HTTP "POST" request. The client constructs the request and making an HTTP "POST" request. The client constructs the request
URI by adding its client credentials to the request as described in URI by adding its client credentials to the request as described in
Section 2, and includes the following parameters using the Section 2, and includes the following parameters using the
"application/x-www-form-urlencoded" format in the HTTP request "application/x-www-form-urlencoded" format in the HTTP request
entity-body: entity-body:
grant_type grant_type
REQUIRED. The access grand type included in the request. REQUIRED. The access grant type included in the request.
Value MUST be one of "authorization_code", Value MUST be one of "authorization-code", "basic-credentials",
"user_basic_credentials", "assertion", "refresh_token", or "assertion", "refresh-token", or "none".
"none" (which indicates the client is acting on behalf of
itself).
scope scope
OPTIONAL. The scope of the access request expressed as a list OPTIONAL. The scope of the access request expressed as a list
of space-delimited strings. The value of the "scope" parameter of space-delimited strings. The value of the "scope" parameter
is defined by the authorization server. If the value contains is defined by the authorization server. If the value contains
multiple space-delimited strings, their order does not matter, multiple space-delimited strings, their order does not matter,
and each string adds an additional access range to the and each string adds an additional access range to the
requested scope. If the access grant being used already requested scope. If the access grant being used already
represents an approved scope (e.g. authorization code, represents an approved scope (e.g. authorization code,
assertion), the requested scope MUST be equal or lesser than assertion), the requested scope MUST be equal or lesser than
the scope previously granted. the scope previously granted.
In addition, the client MUST include the appropriate parameters In addition, the client MUST include the appropriate parameters
listed for the selected access grant type as described in listed for the selected access grant type as described in
Section 4.1. Section 4.1.
4.1. Access Grant Parameters Parameters sent without a value MUST be treated as if they were
omitted from the request.
4.1. Access Grant Types
The client requests an access token using one of the four types of
access grants: authorization code, basic credentials, assertion, or
refresh token.
When requesting an access token using the "none" access grant type
(no access grant is included), the client is requesting access to the
protected resources under its control, or those of another resource
owner which has been previously arranged with the authorization
server (the method of which is beyond the scope of this
specification).
4.1.1. Authorization Code 4.1.1. Authorization Code
The client includes the authorization code using the The client includes the authorization code using the
"authorization_code" access grant type and the following parameters: "authorization-code" access grant type and the following parameters:
code code
REQUIRED. The authorization code received from the REQUIRED. The authorization code received from the
authorization server. authorization server.
redirect_uri redirect_uri
REQUIRED. The redirection URI used in the initial request. REQUIRED. The redirection URI used in the initial request.
For example, the client makes the following HTTPS request (line For example, the client makes the following HTTP request using
breaks are for display purposes only): transport-layer security (line breaks are for display purposes only):
POST /token HTTP/1.1 POST /token HTTP/1.1
Host: server.example.com Host: server.example.com
Content-Type: application/x-www-form-urlencoded Content-Type: application/x-www-form-urlencoded
grant_type=authorization_code&client_id=s6BhdRkqt3& grant_type=authorization-code&client_id=s6BhdRkqt3&
client_secret=gX1fBat3bV&code=i1WsRn1uB1& client_secret=gX1fBat3bV&code=i1WsRn1uB1&
redirect_uri=https%3A%2F%2Fclient%2Eexample%2Ecom%2Fcb redirect_uri=https%3A%2F%2Fclient%2Eexample%2Ecom%2Fcb
The authorization server MUST verify that the authorization code, The authorization server MUST verify that the authorization code,
client identity, client secret, and redirection URI are all valid and client identity, client secret, and redirection URI are all valid and
match its stored association. If the request is valid, the match its stored association. If the request is valid, the
authorization server issues a successful response as described in authorization server issues a successful response as described in
Section 4.2. Section 4.2.
4.1.2. Resource Owner Basic Credentials 4.1.2. Resource Owner Basic Credentials
The client includes the resource owner credentials using the The client includes the resource owner credentials using the
following parameters: [[ add internationalization consideration for "basic-credentials" access grant type and the following parameters:
username and password ]] [[ add internationalization consideration for username and password
]]
username username
REQUIRED. The end-user's username. REQUIRED. The end-user's username.
password password
REQUIRED. The end-user's password. REQUIRED. The end-user's password.
For example, the client makes the following HTTPS request (line For example, the client makes the following HTTP request using
breaks are for display purposes only): transport-layer security (line breaks are for display purposes only):
POST /token HTTP/1.1 POST /token HTTP/1.1
Host: server.example.com Host: server.example.com
Content-Type: application/x-www-form-urlencoded Content-Type: application/x-www-form-urlencoded
grant_type=user_basic&client_id=s6BhdRkqt3& grant_type=basic-credentials&client_id=s6BhdRkqt3&
client_secret=47HDu8s&username=johndoe&password=A3ddj3w client_secret=47HDu8s&username=johndoe&password=A3ddj3w
The authorization server MUST validate the client credentials and The authorization server MUST validate the client credentials and
end-user credentials and if valid issues an access token response as end-user credentials and if valid issues an access token response as
described in Section 4.2. described in Section 4.2.
4.1.3. Assertion 4.1.3. Assertion
The client includes the assertion using the following parameters: The client includes the assertion using the "assertion" access grant
type and the following parameters:
assertion_type assertion_type
REQUIRED. The format of the assertion as defined by the REQUIRED. The format of the assertion as defined by the
authorization server. The value MUST be an absolute URI. authorization server. The value MUST be an absolute URI.
assertion assertion
REQUIRED. The assertion. REQUIRED. The assertion.
For example, the client makes the following HTTPS request (line For example, the client makes the following HTTP request using
breaks are for display purposes only): transport-layer security (line breaks are for display purposes only):
POST /token HTTP/1.1 POST /token HTTP/1.1
Host: server.example.com Host: server.example.com
Content-Type: application/x-www-form-urlencoded Content-Type: application/x-www-form-urlencoded
grant_type=assertion&client_id=s6BhdRkqt3&client_secret=diejdsks& grant_type=assertion&client_id=s6BhdRkqt3&client_secret=diejdsks&
assertion_type=urn%3Aoasis%3Anames%sAtc%3ASAML%3A2.0%3Aassertion& assertion_type=urn%3Aoasis%3Anames%3Atc%3ASAML%3A2.0%3Aassertion&
assertion=PHNhbWxwOl...[ommited for brevity]...ZT4%3D assertion=PHNhbWxwOl...[omitted for brevity]...ZT4%3D
The authorization server MUST validate the assertion and if valid The authorization server MUST validate the assertion and if valid
issues an access token response as described in Section 4.2. The issues an access token response as described in Section 4.2. The
authorization server SHOULD NOT issue a refresh token. authorization server SHOULD NOT issue a refresh token.
Authorization servers SHOULD issue access tokens with a limited Authorization servers SHOULD issue access tokens with a limited
lifetime and require clients to refresh them by requesting a new lifetime and require clients to refresh them by requesting a new
access token using the same assertion if it is still valid. access token using the same assertion if it is still valid.
Otherwise the client MUST obtain a new valid assertion. Otherwise the client MUST obtain a new valid assertion.
4.1.4. Refresh Token 4.1.4. Refresh Token
The client includes the refresh token using the following parameters: The client includes the refresh token using the "refresh-token"
access grant type and the following parameter:
refresh_token refresh_token
REQUIRED. The refresh token associated with the access token REQUIRED. The refresh token associated with the access token
to be refreshed. to be refreshed.
For example, the client makes the following HTTPS request (line break For example, the client makes the following HTTP request using
are for display purposes only): transport-layer security (line break are for display purposes only):
POST /token HTTP/1.1 POST /token HTTP/1.1
Host: server.example.com Host: server.example.com
Content-Type: application/x-www-form-urlencoded Content-Type: application/x-www-form-urlencoded
grant_type=refresh_token&client_id=s6BhdRkqt3& grant_type=refresh-token&client_id=s6BhdRkqt3&
client_secret=8eSEIpnqmM&refresh_token=n4E9O119d client_secret=8eSEIpnqmM&refresh_token=n4E9O119d
The authorization server MUST verify the client credentials, the The authorization server MUST verify the client credentials, the
validity of the refresh token, and that the resource owner's validity of the refresh token, and that the resource owner's
authorization is still valid. If the request is valid, the authorization is still valid. If the request is valid, the
authorization server issues an access token response as described in authorization server issues an access token response as described in
Section 4.2. The authorization server MAY issue a new refresh token Section 4.2. The authorization server MAY issue a new refresh token.
in which case the client MUST NOT use the previous refresh token and
replace it with the newly issued refresh token.
4.2. Access Token Response 4.2. Access Token Response
After receiving and verifying a valid and authorized access token After receiving and verifying a valid and authorized access token
request from the client, the authorization server issues the access request from the client, the authorization server issues the access
token and optional refresh token, and constructs the response by token and optional refresh token, and constructs the response by
adding the following parameters to the entity body of the HTTP adding the following parameters to the entity body of the HTTP
response with a 200 status code (OK): response with a 200 (OK) status code:
The token response contains the following parameters: The token response contains the following parameters:
access_token access_token
REQUIRED. The access token issued by the authorization server. REQUIRED. The access token issued by the authorization server.
expires_in expires_in
OPTIONAL. The duration in seconds of the access token OPTIONAL. The duration in seconds of the access token
lifetime. lifetime. For example, the value "3600" denotes that the
access token will expire in one hour from the time the response
was generated by the authorization server.
refresh_token refresh_token
OPTIONAL. The refresh token used to obtain new access tokens OPTIONAL. The refresh token used to obtain new access tokens
using the same end-user access grant as described in using the same end-user access grant as described in
Section 4.1.4. Section 4.1.4.
scope scope
OPTIONAL. The scope of the access token as a list of space- OPTIONAL. The scope of the access token as a list of space-
delimited strings. The value of the "scope" parameter is delimited strings. The value of the "scope" parameter is
defined by the authorization server. If the value contains defined by the authorization server. If the value contains
skipping to change at page 22, line 29 skipping to change at page 26, line 47
HTTP/1.1 200 OK HTTP/1.1 200 OK
Content-Type: application/json Content-Type: application/json
Cache-Control: no-store Cache-Control: no-store
{ {
"access_token":"SlAV32hkKG", "access_token":"SlAV32hkKG",
"expires_in":3600, "expires_in":3600,
"refresh_token":"8xLOxBtZp8" "refresh_token":"8xLOxBtZp8"
} }
The sizes of tokens and other values received from the authorization
server, are left undefined by this specification. Clients should
avoid making assumptions about value sizes. Servers should document
the expected size of any value they issue.
4.3. Error Response 4.3. Error Response
If the token request is invalid or unauthorized, the authorization If the token request is invalid or unauthorized, the authorization
server constructs the response by adding the following parameter to server constructs the response by adding the following parameter to
the entity body of the HTTP response with a a 400 status code (Bad the entity body of the HTTP response using the "application/json"
Request) using the "application/json" media type: media type:
error error
REQUIRED. The error code as described in Section 4.3.1. REQUIRED. A single error code as described in Section 4.3.1.
error_description OPTIONAL. A human-readable text providing
additional information, used to assist in the understanding and
resolution of the error occurred.
error_uri OPTIONAL. A URI identifying a human-readable web page
with information about the error, used to provide the end-user
with additional information about the error.
For example: For example:
HTTP/1.1 400 Bad Request HTTP/1.1 400 Bad Request
Content-Type: application/json Content-Type: application/json
Cache-Control: no-store Cache-Control: no-store
{ {
"error":"incorrect_client_credentials" "error":"invalid-request"
} }
4.3.1. Error Codes If the client provided invalid credentials using an HTTP
authentication scheme via the "Authorization" request header field,
[[ expalain each error code: ]] the authorization server MUST respond with the HTTP 401
(Unauthorized) status code. Otherwise, the authorization server
SHALL respond with the HTTP 400 (Bad Request) status code.
o "redirect_uri_mismatch" 4.3.1. Error Codes
o "bad_authorization_code" The authorization server includes one of the following error codes
with the error response:
o "invalid_client_credentials" invalid-request
The request is missing a required parameter, includes an
unknown parameter or parameter value, repeats a parameter,
includes multiple credentials, utilizes more than one mechanism
for authenticating the client, or is otherwise malformed.
o "unauthorized_client'" - The client is not permitted to use this invalid-client-credentials
access grant type. The client identifier provided is invalid, the client failed to
authenticate, or the client provided multiple client
credentials.
o "invalid_assertion" unauthorized-client
The client is not authorized to use the access grant type
provided.
o "unknown_format" invalid-grant
The provided access grant is invalid, expired, or revoked (e.g.
invalid assertion, expired authorization token, bad end-user
basic credentials, or mismatching authorization code and
redirection URI).
o "authorization_expired" unsupported-grant-type
The access grant included - its type or another attribute - is
not supported by the authorization server.
o "multiple_credentials" invalid-scope
The requested scope is invalid, unknown, malformed, or exceeds
the previously granted scope.
o "invalid_user_credentials" [[ Add mechanism for extending error codes ]]
5. Accessing a Protected Resource 5. Accessing a Protected Resource
Clients access protected resources by presenting an access token to Clients access protected resources by presenting an access token to
the resource server. the resource server. Access tokens act as bearer tokens, where the
token string acts as a shared symmetric secret. This requires
For example: treating the access token with the same care as other secrets (e.g.
end-user passwords). Access tokens SHOULD NOT be sent in the clear
GET /resource HTTP/1.1 over an insecure channel.
Host: server.example.com
Authorization: Token token="vF9dft4qmT"
Access tokens act as bearer tokens, where the token string acts as a
shared symmetric secret. This requires treating the access token
with the same care as other secrets (e.g. end-user passwords).
Access tokens SHOULD NOT be sent in the clear over an insecure
channel.
However, when it is necessary to transmit bearer tokens in the clear However, when it is necessary to transmit access tokens in the clear
without a secure channel, authorization servers SHOULD issue access without a secure channel, authorization servers SHOULD issue access
tokens with limited scope and lifetime to reduce the potential risk tokens with limited scope and lifetime to reduce the potential risk
from a compromised access token. from a compromised access token.
Clients SHOULD NOT make authenticated requests with an access token Clients MUST NOT make authenticated requests with an access token to
to unfamiliar resource servers, especially when using bearer tokens, unfamiliar resource servers, regardless of the presence of a secure
regardless of the presence of a secure channel. channel.
The methods used by the resource server to validate the access token The resource server MUST validate the access token and ensure it has
are beyond the scope of this specification, but generally involve an not expired and that its scope covers the requested resource. The
methods used by the resource server to validate the access token are
beyond the scope of this specification, but generally involve an
interaction or coordination between the resource server and interaction or coordination between the resource server and
authorization server. authorization server.
The resource server MUST validate the access token and ensure it has 5.1. Authenticated Requests
not expired and that its scope covers the requested resource. If the
token expired or is invalid, the resource server MUST reply with an
HTTP 401 status code (Unauthorized) and include the HTTP
"WWW-Authenticate" response header field as described in Section 6.
For example:
HTTP/1.1 401 Unauthorized
WWW-Authenticate: Token realm='Service', error='token_expired'
Clients make authenticated token requests using the "Authorization" Clients make authenticated token requests using the "Authorization"
request header field as described in Section 5.1. Alternatively, request header field as described in Section 5.1.1. Alternatively,
clients MAY include the access token using the HTTP request URI in clients MAY include the access token using the HTTP request URI in
the query component as described in Section 5.2, or in the HTTP body the query component as described in Section 5.1.2, or in the HTTP
when using the "application/x-www-form-urlencoded" content type as body when using the "application/x-www-form-urlencoded" content type
described in Section 5.3. as described in Section 5.1.3.
Clients SHOULD only use the request URI or body when the Clients SHOULD only use the request URI or body when the
"Authorization" request header field is not available, and MUST NOT "Authorization" request header field is not available, and MUST NOT
use more than one method in each request. [[ specify error ]] use more than one method in each request.
5.1. The Authorization Request Header Field 5.1.1. The Authorization Request Header Field
The "Authorization" request header field is used by clients to make The "Authorization" request header field is used by clients to make
authenticated token requests. The client uses the "token" attribute authenticated token requests. The client uses the "token" attribute
to include the access token in the request. to include the access token in the request.
For example:
GET /resource HTTP/1.1
Host: server.example.com
Authorization: Token token="vF9dft4qmT"
The "Authorization" header field uses the framework defined by The "Authorization" header field uses the framework defined by
[RFC2617] as follows: [RFC2617] as follows:
credentials = "Token" RWS access-token [ CS 1#auth-param ] credentials = "Token" RWS access-token [ CS 1#auth-param ]
access-token = "token" "=" <"> token <"> access-token = "token" "=" <"> token <">
CS = OWS "," OWS CS = OWS "," OWS
5.2. URI Query Parameter 5.1.2. URI Query Parameter
When including the access token in the HTTP request URI, the client When including the access token in the HTTP request URI, the client
adds the access token to the request URI query component as defined adds the access token to the request URI query component as defined
by [RFC3986] using the "oauth_token" parameter. by [RFC3986] using the "oauth_token" parameter.
For example, the client makes the following HTTPS request: For example, the client makes the following HTTP request using
transport-layer security:
GET /resource?oauth_token=vF9dft4qmT HTTP/1.1 GET /resource?oauth_token=vF9dft4qmT HTTP/1.1
Host: server.example.com Host: server.example.com
The HTTP request URI query can include other request-specific The HTTP request URI query can include other request-specific
parameters, in which case, the "oauth_token" parameters SHOULD be parameters, in which case, the "oauth_token" parameters SHOULD be
appended following the request-specific parameters, properly appended following the request-specific parameters, properly
separated by an "&" character (ASCII code 38). separated by an "&" character (ASCII code 38).
The resource server MUST validate the access token and ensure it has For example:
not expired and its scope includes the requested resource. If the
resource expired or is not valid, the resource server MUST reply with
an HTTP 401 status code (Unauthorized) and include the HTTP
"WWW-Authenticate" response header field as described in Section 6.
5.3. Form-Encoded Body Parameter http://example.com/resource?x=y&oauth_token=vF9dft4qmT
5.1.3. Form-Encoded Body Parameter
When including the access token in the HTTP request entity-body, the When including the access token in the HTTP request entity-body, the
client adds the access token to the request body using the client adds the access token to the request body using the
"oauth_token" parameter. The client can use this method only if the "oauth_token" parameter. The client can use this method only if the
following REQUIRED conditions are met: following REQUIRED conditions are met:
o The entity-body is single-part. o The entity-body is single-part.
o The entity-body follows the encoding requirements of the o The entity-body follows the encoding requirements of the
"application/x-www-form-urlencoded" content-type as defined by "application/x-www-form-urlencoded" content-type as defined by
skipping to change at page 26, line 5 skipping to change at page 31, line 5
o The HTTP request entity-header includes the "Content-Type" header o The HTTP request entity-header includes the "Content-Type" header
field set to "application/x-www-form-urlencoded". field set to "application/x-www-form-urlencoded".
o The HTTP request method is "POST", "PUT", or "DELETE". o The HTTP request method is "POST", "PUT", or "DELETE".
The entity-body can include other request-specific parameters, in The entity-body can include other request-specific parameters, in
which case, the "oauth_token" parameters SHOULD be appended following which case, the "oauth_token" parameters SHOULD be appended following
the request-specific parameters, properly separated by an "&" the request-specific parameters, properly separated by an "&"
character (ASCII code 38). character (ASCII code 38).
For example, the client makes the following HTTPS request: For example, the client makes the following HTTP request using
transport-layer security:
POST /resource HTTP/1.1 POST /resource HTTP/1.1
Host: server.example.com Host: server.example.com
Content-Type: application/x-www-form-urlencoded Content-Type: application/x-www-form-urlencoded
oauth_token=vF9dft4qmT oauth_token=vF9dft4qmT
The resource server MUST validate the access token and ensure it has 5.2. The WWW-Authenticate Response Header Field
not expired and its scope includes the requested resource. If the
resource expired or is not valid, the resource server MUST reply with
an HTTP 401 status code (Unauthorized) and include the HTTP
"WWW-Authenticate" response header field as described in Section 6.
6. The WWW-Authenticate Response Header Field
Clients access protected resources after locating the appropriate
end-user authorization endpoint and token endpoint and obtaining an
access token. In many cases, interacting with a protected resource
requires prior knowledge of the protected resource properties and
methods, as well as its authentication requirements (i.e.
establishing client identity, locating the end-user authorization and
token endpoints).
However, there are cases in which clients are unfamiliar with the
protected resource, including whether the resource requires
authentication. When clients attempt to access an unfamiliar
protected resource without an access token, the resource server
denies the request and informs the client of the required credentials
using an HTTP authentication challenge.
In addition, when receiving an invalid authenticated request, the
resource server issues an authentication challenge including the
error type and message.
A resource server receiving a request for a protected resource
without a valid access token MUST respond with a 401 (Unauthorized)
or 403 (Forbidden) HTTP status code, and include at least one "Token"
"WWW-Authenticate" response header field challenge.
The "WWW-Authenticate" header field uses the framework defined by If the protected resource request contains an invalid access token or
[RFC2617] as follows: is malformed, the resource server MUST include the HTTP
"WWW-Authenticate" response header field. The "WWW-Authenticate"
header field uses the framework defined by [RFC2617] as follows:
challenge = "Token" RWS token-challenge challenge = "Token" RWS token-challenge
token-challenge = realm token-challenge = realm
[ CS error ] [ CS error ]
[ CS error-desc ]
[ CS error-uri ]
[ CS scope ]
[ CS 1#auth-param ] [ CS 1#auth-param ]
error = "error" "=" <"> token <"> error = "error" "=" <"> token <">
error-desc = "error-description" "=" quoted-string
error-uri = "error-uri" = <"> URI-Reference <">
scope = ptoken / <"> ptoken *( 1*SP ptoken ) <">
ptoken = 1*ptokenchar
ptokenchar = "!" / "#" / "$" / "%" / "&" / "'" / "("
/ ")" / "*" / "+" / "-" / "." / "/" / DIGIT
/ ":" / "<" / "=" / ">" / "?" / "@" / ALPHA
/ "[" / "]" / "^" / "_" / "`" / "{" / "|"
/ "}" / "~"
For example:
HTTP/1.1 401 Unauthorized
WWW-Authenticate: Token realm='Example Service', error='expired-token'
The "realm" attribute is used to provide the protected resources The "realm" attribute is used to provide the protected resources
partition as defined by [RFC2617]. partition as defined by [RFC2617]. [[ add explanation ]]
The "error" attribute is used to inform the client the reason why an The "error" attribute is used to provide the client with the reason
access request was declined. [[ Add list of error codes ]] why the access request was declined. The parameter values are
described in Section 5.2.1.
The "error-description" attribute provides a human-readable text
containing additional information, used to assist in the
understanding and resolution of the error occurred.
The "error-uri" attribute provides a URI identifying a human-readable
web page with information about the error, used to offer the end-user
with additional information about the error. If the value is not an
absolute URI, it is relative to the URI of the requested protected
resource.
The "scope" attribute is a space-delimited list of scope values
indicating the required scope of the access token for accessing the
requested resource.
5.2.1. Error Codes
The authorization server includes one of the following error codes
with the error response:
invalid-request
The request is missing a required parameter, includes an
unknown parameter or parameter value, repeats the same
parameter, uses more than one method for including an access
token, or is otherwise malformed. The resource server MUST
respond with the HTTP 400 (Bad Request) status code.
invalid-token
The access token provided is invalid. Resource servers SHOULD
use this error code when receiving an expired token which
cannot be refreshed to indicate to the client that a new
authorization is necessary. The resource server MUST respond
with the HTTP 401 (Unauthorized) status code.
expired-token
The access token provided has expired. Resource servers SHOULD
only use this error code when the client is expected to be able
to handle the response and request a new access token using the
refresh token issued with the expired access token. The
resource server MUST respond with the HTTP 401 (Unauthorized)
status code.
insufficient-scope
The request requires higher privileges than provided by the
access token. The resource server SHOULD respond with the HTTP
403 (Forbidden) status code and MAY include the "scope"
attribute with the scope necessary to access the protected
resource.
[[ Add mechanism for extending error codes ]]
If the request lacks any authentication information (i.e. the client
was unaware authentication is necessary), the resource server SHOULD
not include an error code or other error information.
For example:
HTTP/1.1 401 Unauthorized
WWW-Authenticate: Token realm='Example Service'
6. Extensibility
6.1. Defining New Client Credentials Types
[[ TBD ]]
6.2. Defining New Endpoint Parameters
Applications that wish to define new request or response parameters
for use with the end-user authorization endpoint or the token
endpoint SHALL do so in one of two ways: register them in the
parameters registry (following the procedures in Section 8.1), or use
the "x_" parameter name prefix.
Parameters utilizing the "x_" parameter name prefix MUST be limited
to vendor-specific extensions that are not commonly applicable, and
are specific to the implementation details of the authorization
server where they are used. All other new parameters MUST be
registered, and MUST NOT use the "x_" parameter name prefix.
Parameter names MUST conform to the param-name ABNF, and parameter
values syntax MUST be well-defined (e.g., using ABNF, or a reference
to the syntax of an existing parameter).
param-name = 1*fchar
fchar = "-" / "." / "_" / DIGIT / ALPHA
6.3. Defining New Header Field Parameters
Applications that wish to define new parameters for use in the OAuth
"Authorization" or "WWW-Authenticate" header fields MUST register
them in the parameters registry, following the procedures in
Section 8.1.
Parameter names MUST conform to the param-name ABNF and MUST NOT
begin with "x_". Parameter values MUST conform to the param-value
ABNF and their syntax MUST be well-defined (e.g., using ABNF, or a
reference to the syntax of an existing parameter).
param-value = ptoken | quoted-string
6.4. Defining New Access Grant Types
The assertion access grant type was designed to allow the
authorization server to accept additional access grants not
specified. Applications that wish to define additional access grant
types can do so by utilizing a new or existing assertion type and
format.
7. Security Considerations 7. Security Considerations
[[ todo ]] [[ TBD ]]
8. IANA Considerations 8. IANA Considerations
[[ Not Yet ]] 8.1. The OAuth Parameters Registry
This document establishes the OAuth parameters registry.
Additional parameters to be use in the end-user authorization
endpoint request, the end-user authorization endpoint response, the
token endpoint request, the token endpoint response, the
"Authorization" header field, or the "WWW-Authenticate" header field,
are registered on the advice of one or more Designated Experts
(appointed by the IESG or their delegate), with a Specification
Required (using terminology from [RFC5226]). 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 should be sent to the [TBD]@ietf.org mailing
list for review and comment, with an appropriate subject (e.g.,
"Request for parameter: example"). [[ Note to RFC-EDITOR: The name of
the mailing list should be determined in consultation with the IESG
and IANA. Suggested name: oauth-ext-review. ]]
Before a period of 14 days has passed, the Designated Expert(s) will
either approve or deny the registration request, communicating this
decision both to the review list and to IANA. Denials should include
an explanation and, if applicable, suggestions as to how to make the
request successful. Registration requests that are undetermined for
a period longer than 21 days can be brought to the IESG's attention
(using the iesg@iesg.org mailing list) for resolution.
8.1.1. Registration Template
Parameter name: The name requested (e.g., "example").
Parameter usage location: The location(s) where parameter can be
used. The possible locations are: the end-user authorization
endpoint request, the end-user authorization endpoint response,
the token endpoint request, the token endpoint response, the
"Authorization" header field, or the "WWW-Authenticate" header
field.
Change controller: For standards-track RFCs, state "IETF". For
others, give the name of the responsible party. Other details
(e.g., postal address, e-mail address, home page URI) may also be
included.
Specification document(s): Reference to document that specifies the
parameter, preferably including a URI that can be used to retrieve
a copy of the document. An indication of the relevant sections
may also be included, but is not required.
Related information: Optionally, citations to additional documents
containing further relevant information.
8.1.2. Example
The following is the parameter registration request for the "scope"
parameter as defined in this specification:
Parameter name: scope
Parameter usage location: The end-user authorization endpoint
request, the end-user authorization endpoint response, the token
endpoint request, the token endpoint response, and the
"WWW-Authenticate" header field.
Change controller: IETF
Specification document(s): [[ this document ]]
Related information: None
Appendix A. Examples Appendix A. Examples
[[ todo ]] [[ TBD ]]
Appendix B. Contributors Appendix B. Contributors
The following people contributed to preliminary versions of this The following people contributed to preliminary versions of this
document: Blaine Cook (BT), Brian Eaton (Google), Yaron Goland document: Blaine Cook (BT), Brian Eaton (Google), Yaron Goland
(Microsoft), Brent Goldman (Facebook), Raffi Krikorian (Twitter), (Microsoft), Brent Goldman (Facebook), Raffi Krikorian (Twitter),
Luke Shepard (Facebook), and Allen Tom (Yahoo!). The content and Luke Shepard (Facebook), and Allen Tom (Yahoo!). The content and
concepts within are a product of the OAuth community, WRAP community, concepts within are a product of the OAuth community, WRAP community,
and the OAuth Working Group. and the OAuth Working Group.
The OAuth Working Group has dozens of very active contributors who The OAuth Working Group has dozens of very active contributors who
proposed ideas and wording for this document, including: [[ If your proposed ideas and wording for this document, including: [[ If your
name is missing or you think someone should be added here, please name is missing or you think someone should be added here, please
send Eran a note - don't be shy ]] send Eran a note - don't be shy ]]
Michael Adams, Andrew Arnott, Dirk Balfanz, Brian Campbell, Leah Michael Adams, Andrew Arnott, Dirk Balfanz, Brian Campbell, Leah
Culver, Igor Faynberg, George Fletcher, Evan Gilbert, Justin Hart, Culver, Brian Ellin, Igor Faynberg, George Fletcher, Evan Gilbert,
John Kemp, Torsten Lodderstedt, Eve Maler, James Manger, Chuck Justin Hart, John Kemp, Chasen Le Hara, Torsten Lodderstedt, Eve
Mortimore, Justin Richer, Peter Saint-Andre, Nat Sakimura, Rob Sayre, Maler, James Manger, Laurence Miao, Chuck Mortimore, Justin Richer,
Marius Scurtescu, Justin Smith, and Franklin Tse. Peter Saint-Andre, Nat Sakimura, Rob Sayre, Marius Scurtescu, Justin
Smith, Jeremy Suriel, and Franklin Tse.
Appendix C. Acknowledgements Appendix C. Acknowledgements
[[ Add OAuth 1.0a authors + WG contributors ]] [[ Add OAuth 1.0a authors + WG contributors ]]
Appendix D. Document History Appendix D. Document History
[[ to be removed by RFC editor before publication as an RFC ]] [[ to be removed by RFC editor before publication as an RFC ]]
-09
o Fixed typos, editorial changes.
o Added token expiration example.
o Added scope parameter to end-user authorization endpoint response.
o Added note about parameters with empty values (same as omitted).
o Changed parameter values to use '-' instead of '_'. Parameter
names still use '_'.
o Changed authorization endpoint client type to response type with
values: code, token, and both.
o Complete cleanup of error codes. Added support for error
description and URI.
o Add initial extensibility support.
-08 -08
o Renamed verification code to authorization code. o Renamed verification code to authorization code.
o Revised terminology, structured section, added new terms. o Revised terminology, structured section, added new terms.
o Changed flows to profiles and moved to introduction. o Changed flows to profiles and moved to introduction.
o Added support for access token rescoping. o Added support for access token rescoping.
skipping to change at page 32, line 15 skipping to change at page 41, line 22
[RFC3629] Yergeau, F., "UTF-8, a transformation format of ISO [RFC3629] Yergeau, F., "UTF-8, a transformation format of ISO
10646", STD 63, RFC 3629, November 2003. 10646", STD 63, RFC 3629, November 2003.
[RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform [RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
Resource Identifier (URI): Generic Syntax", STD 66, Resource Identifier (URI): Generic Syntax", STD 66,
RFC 3986, January 2005. RFC 3986, January 2005.
[RFC4627] Crockford, D., "The application/json Media Type for [RFC4627] Crockford, D., "The application/json Media Type for
JavaScript Object Notation (JSON)", RFC 4627, July 2006. 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 [RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security
(TLS) Protocol Version 1.2", RFC 5246, August 2008. (TLS) Protocol Version 1.2", RFC 5246, August 2008.
[W3C.REC-html401-19991224] [W3C.REC-html401-19991224]
Hors, A., Raggett, D., and I. Jacobs, "HTML 4.01 Hors, A., Jacobs, I., and D. Raggett, "HTML 4.01
Specification", World Wide Web Consortium Specification", World Wide Web Consortium
Recommendation REC-html401-19991224, December 1999, Recommendation REC-html401-19991224, December 1999,
<http://www.w3.org/TR/1999/REC-html401-19991224>. <http://www.w3.org/TR/1999/REC-html401-19991224>.
9.2. Informative References 9.2. Informative References
[I-D.hammer-oauth] [I-D.hammer-oauth]
Hammer-Lahav, E., "The OAuth 1.0 Protocol", Hammer-Lahav, E., "The OAuth 1.0 Protocol",
draft-hammer-oauth-10 (work in progress), February 2010. draft-hammer-oauth-10 (work in progress), February 2010.
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