draft-ietf-oauth-v2-00.txt   draft-ietf-oauth-v2-01.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: October 31, 2010 Facebook Expires: October 31, 2010 Facebook
D. Hardt D. Hardt
April 29, 2010 April 29, 2010
The OAuth 2.0 Protocol The OAuth 2.0 Protocol
draft-ietf-oauth-v2-00 draft-ietf-oauth-v2-01
Abstract Abstract
This specification describes the OAuth 2.0 protocol. OAuth provides This specification describes the OAuth 2.0 protocol. OAuth provides
a method for making authenticated HTTP requests using a token - an a method for making authenticated HTTP requests using a token - an
identifier used to denote an access grant with specific scope, identifier used to denote an access grant with specific scope,
duration, and other attributes. Tokens are issued to third-party duration, and other attributes. Tokens are issued to third-party
clients by an authorization server with the approval of the resource clients by an authorization server with the approval of the resource
owner. OAuth defines multiple flows for obtaining a token to support owner. OAuth defines multiple flows for obtaining a token to support
a wide range of client types and user experience. a wide range of client types and user experience.
skipping to change at page 3, line 21 skipping to change at page 3, line 21
2.3. Example . . . . . . . . . . . . . . . . . . . . . . . . . 8 2.3. Example . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.4. Notational Conventions . . . . . . . . . . . . . . . . . . 8 2.4. Notational Conventions . . . . . . . . . . . . . . . . . . 8
2.5. Conformance . . . . . . . . . . . . . . . . . . . . . . . 8 2.5. Conformance . . . . . . . . . . . . . . . . . . . . . . . 8
3. Obtaining an Access Token . . . . . . . . . . . . . . . . . . 8 3. Obtaining an Access Token . . . . . . . . . . . . . . . . . . 8
3.1. Authorization Endpoint . . . . . . . . . . . . . . . . . . 9 3.1. Authorization Endpoint . . . . . . . . . . . . . . . . . . 9
3.2. Token Endpoint . . . . . . . . . . . . . . . . . . . . . . 9 3.2. Token Endpoint . . . . . . . . . . . . . . . . . . . . . . 9
3.3. Flow Parameters . . . . . . . . . . . . . . . . . . . . . 10 3.3. Flow Parameters . . . . . . . . . . . . . . . . . . . . . 10
3.4. Client Credentials . . . . . . . . . . . . . . . . . . . . 10 3.4. Client Credentials . . . . . . . . . . . . . . . . . . . . 10
3.5. User Delegation Flows . . . . . . . . . . . . . . . . . . 11 3.5. User Delegation Flows . . . . . . . . . . . . . . . . . . 11
3.5.1. User-Agent Flow . . . . . . . . . . . . . . . . . . . 11 3.5.1. User-Agent Flow . . . . . . . . . . . . . . . . . . . 11
3.5.2. Web Server Flow . . . . . . . . . . . . . . . . . . . 15 3.5.2. Web Server Flow . . . . . . . . . . . . . . . . . . . 16
3.5.3. Device Flow . . . . . . . . . . . . . . . . . . . . . 21 3.5.3. Device Flow . . . . . . . . . . . . . . . . . . . . . 22
3.6. End User Credentials Flows . . . . . . . . . . . . . . . . 27 3.6. End-user Credentials Flows . . . . . . . . . . . . . . . . 27
3.6.1. Username and Password Flow . . . . . . . . . . . . . . 27 3.6.1. Username and Password Flow . . . . . . . . . . . . . . 27
3.7. Autonomous Client Flows . . . . . . . . . . . . . . . . . 30 3.7. Autonomous Client Flows . . . . . . . . . . . . . . . . . 30
3.7.1. Client Credentials Flow . . . . . . . . . . . . . . . 30 3.7.1. Client Credentials Flow . . . . . . . . . . . . . . . 30
3.7.2. Assertion Flow . . . . . . . . . . . . . . . . . . . . 33 3.7.2. Assertion Flow . . . . . . . . . . . . . . . . . . . . 33
4. Refreshing an Access Token . . . . . . . . . . . . . . . . . . 35 4. Refreshing an Access Token . . . . . . . . . . . . . . . . . . 35
5. Accessing a Protected Resource . . . . . . . . . . . . . . . . 38 5. Accessing a Protected Resource . . . . . . . . . . . . . . . . 38
5.1. The Authorization Request Header . . . . . . . . . . . . . 38 5.1. The Authorization Request Header . . . . . . . . . . . . . 38
5.2. Bearer Token Requests . . . . . . . . . . . . . . . . . . 40 5.2. Bearer Token Requests . . . . . . . . . . . . . . . . . . 40
5.2.1. URI Query Parameter . . . . . . . . . . . . . . . . . 40 5.2.1. URI Query Parameter . . . . . . . . . . . . . . . . . 40
5.2.2. Form-Encoded Body Parameter . . . . . . . . . . . . . 41 5.2.2. Form-Encoded Body Parameter . . . . . . . . . . . . . 41
skipping to change at page 4, line 27 skipping to change at page 4, line 27
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). In the traditional client-server
authentication model, a client accessing a protected resource on a authentication model, a client accessing a protected resource on a
server presents the resource owner's credentials in order to server presents the resource owner's credentials in order to
authenticate and gain access. authenticate and gain access.
Resource owners should not be required to share their credentials Resource owners should not be required to share their credentials
when granting third-party applications access to their protected when granting third-party applications access to their protected
resources. They should also have the ability to restrict access to a resources. They should also have the ability to restrict access to a
limited subset of the resources they control, to limit access limited subset of the resources they control, to limit access
duration, or to limit access to the methods supported by these duration, or to limit access to the HTTP methods supported by these
resources. resources.
OAuth provides a method for making authenticated HTTP requests using OAuth provides a method for making authenticated HTTP requests using
a token - an identifier used to denote an access grant with specific a token - an identifier used to denote an access grant with specific
scope, duration, and other attributes. Tokens are issued to third- scope, duration, and other attributes. Tokens are issued to third-
party clients by an authorization server with the approval of the party clients by an authorization server with the approval of the
resource owner. Instead of sharing their credentials with the resource owner. Instead of sharing their credentials with the
client, resource owners grant access by authenticating directly with client, resource owners grant access by authenticating directly with
the authorization server which in turn issues a token to the client. the authorization server which in turn issues a token to the client.
The client uses the token (and optional secret) to authenticate with The client uses the token (and optional secret) to authenticate with
the resource server and gain access. the resource server and gain access.
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).
The use of OAuth with any other transport protocol than HTTP This specification defines the use of OAuth over HTTP [RFC2616] (or
[RFC2616] (or HTTP over TLS 1.0 as defined by [RFC2818] is undefined. HTTP over TLS 1.0 as defined by [RFC2818]. Other specifications may
extend it for use with other tranport protocols.
2.1. Terminology 2.1. Terminology
resource server resource server
An HTTP [RFC2616] server capable of accepting authenticated An HTTP [RFC2616] server capable of accepting authenticated
resource requests using the OAuth protocol. resource requests using the OAuth protocol.
protected resource protected resource
An access-restricted resource which can be obtained from a An access-restricted resource which can be obtained from a
resource server using an OAuth-authenticated request. resource server using an OAuth-authenticated request.
client client
An HTTP client capable of making authenticated requests for An HTTP client capable of making authenticated requests for
protected resources using the OAuth protocol. protected resources using the OAuth protocol.
resource owner resource owner
An entity capable of granting access to a protected resource. An entity capable of granting access to a protected resource.
end user end-user
A human resource owner. A human resource owner.
access token access token
A unique identifier used by the client to make authenticated A unique identifier used by the client to make authenticated
requests on behalf of the resource owner. Access tokens may requests on behalf of the resource owner. Access tokens may
have a matching secret. have a matching secret.
bearer token An access token without a matching secret, used to
obtain access to a protected resource by simply presenting the
access token as-is to the resource server.
authorization server authorization server
An HTTP server capable of issuing tokens after successfully An HTTP 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.
authorization endpoint authorization endpoint
The authorization server's HTTP endpoint capable of The authorization server's HTTP endpoint capable of
authenticating the resource owner and obtaining authorization. authenticating the resource owner and obtaining authorization.
skipping to change at page 7, line 21 skipping to change at page 7, line 21
| | HTTP Request +---------------+ | | HTTP Request +---------------+
| |--(C)--- with Access Token ------>| Resource | | |--(C)--- with Access Token ------>| Resource |
| | | Server | | | | Server |
| |<-(D)----- HTTP Response ---------| | | |<-(D)----- HTTP Response ---------| |
+--------+ +---------------+ +--------+ +---------------+
Figure 2 Figure 2
This specification defines a number of authorization flows to support This specification defines a number of authorization flows to support
different client types and scenarios. These authorization flows can different client types and scenarios. These authorization flows can
be separated into three groups: user delegation flows where the be separated into three groups: user delegation flows, end-user
client is acting on behalf of an end user, end user credentials flows credentials flows, and autonomous flows.
where the client uses the end user's credentials directly to obtain
authorization, and autonomous flows where the client is acting for
itself (the client is also the resource owner).
Additional authorization flows may be defined by other specifications Additional authorization flows may be defined by other specifications
to cover different scenarios and client types. to cover different scenarios and client types.
The user delegation authorization flows defined by this User delegation authorization enable clients to act on behalf of an
specifications are: end-user after obtaining authorization from the end-user. The user
delegation flows defined by this specifications are:
o User-Agent Flow - This flow is designed for clients running inside o User-Agent Flow - This flow is designed for clients running inside
a user-agent (typically a web browser), and therefore cannot a user-agent (typically a web browser). This flow is described in
receive incoming requests from the authorization server. This Section 3.5.1.
flow is described in Section 3.5.1.
o Web Server Flow - This flow is optimized for cases where the o Web Server Flow - This flow is optimized for clients that are part
client is capable of receiving incoming HTTP requests (act as an of a web server application, accessible via HTTP requests. This
HTTP server). This flow is described in Section 3.5.2. flow is described in Section 3.5.2.
o Device Flow - This flow suitable for clients executing on limited o Device Flow - This flow is suitable for clients executing on
devices, but where the end user has separate access to a user- limited devices, but where the end-user has separate access to a
agent on another computer or device. This flow is described in user-agent on another computer or device. This flow is described
Section 3.5.3. in Section 3.5.3.
The end user credentials flow defined by this specification is: End-user credentials flow enable clients with direct access to the
end-user's credentials to exchange them for an access token without
seeking additional authorization. These flows are only suitable when
there is a high degree of trust between the end-user and the client.
The end-user credentials flow defined by this specification is:
o Username and Password Flow - This flow is used in cases where the o Username and Password Flow - This flow is used in cases where the
end user trusts the client to handle its credentials but it is end-user trusts the client to handle its credentials but it is
still undesirable for the client to store the end user's username still undesirable for the client to store the end-user's username
and password. This flow is described in Section 3.6.1. and password. This flow is described in Section 3.6.1.
The autonomous authorization flows defined by this specifications Autonomous flows enable clients to act for their own behalf (the
are: client is also the resource owner). The autonomous authorization
flows defined by this specifications are:
o Client Credentials Flow - The client uses its credentials to o Client Credentials Flow - The client uses its credentials to
obtain an access token. This flow is described in Section 3.7.1. obtain an access token. This flow is described in Section 3.7.1.
o Assertion Flow - The client presents an assertion such as a SAML o Assertion Flow - The client presents an assertion such as a SAML
[OASIS.saml-core-2.0-os] assertion to the authorization server in [OASIS.saml-core-2.0-os] assertion to the authorization server in
exchange for an access token. This flow is described in exchange for an access token. This flow is described in
Section 3.7.2. Section 3.7.2.
2.3. Example 2.3. Example
skipping to change at page 8, line 49 skipping to change at page 9, line 5
MUST level requirements but not all the SHOULD level requirements for MUST level requirements but not all the SHOULD level requirements for
its flows is said to be "conditionally compliant." its flows is said to be "conditionally compliant."
3. Obtaining an Access Token 3. Obtaining an Access Token
The client obtains an access token by using one of the authorization The client obtains an access token by using one of the authorization
flows supported by the authorization server. The authorization flows flows supported by the authorization server. The authorization flows
all use the same authorization and token endpoints, each with a all use the same authorization and token endpoints, each with a
different set of request parameters and values. different set of request parameters and values.
When issuing an access token, the scope, duration, and other access Access tokens have a scope, duration, and other access attributes
attributes granted by the resource owner must be retained and granted by the resource owner. These attributes MUST be enforced by
enforced by the resource server when receiving a protected resource the resource server when receiving a protected resource request, and
request and by the authorization server when receiving a token by the authorization server when receiving a token refresh request.
refresh request made with the access token issued.
In many cases it is desirable to issue access tokens with a shorter In many cases it is desirable to issue access tokens with a shorter
lifetime than the duration of the authorization grant. However, it lifetime than the duration of the authorization grant. However, it
may be undesirable to require the resource owner to authorize the may be undesirable to require the resource owner to authorize the
request again. Instead, the authorization server issues a refresh request again. Instead, the authorization server issues a refresh
token in addition to the access token. When the access token token in addition to the access token. When the access token
expires, the client can request a new access token without involving expires, the client can request a new access token without involving
the resource owner as long as the authorization grant is still valid. the resource owner as long as the authorization grant is still valid.
The token refresh method is described in Section 4. The token refresh method is described in Section 4.
3.1. Authorization Endpoint 3.1. Authorization Endpoint
Clients direct the resource owner to the authorization endpoint to Clients direct the resource owner to the authorization endpoint to
approve their access request. Before granting access, the resource approve their access request. Before granting access, the resource
owner first authenticate with the authorization server. The way in owner first authenticates with the authorization server. The way in
which the authorization server authenticates the end user (e.g. which the authorization server authenticates the end-user (e.g.
username and password login, OpenID, session cookies) and in which username and password login, OpenID, session cookies) and in which
the authorization server obtains the end user's authorization, the authorization server obtains the end-user's authorization,
including whether it uses a secure channel such as TLS/SSL, is beyond including whether it uses a secure channel such as TLS/SSL, is beyond
the scope of this specification. However, the authorization server the scope of this specification. However, the authorization server
MUST first verify the identity of the end user. MUST first verify the identity of the end-user.
The URI of the authorization endpoint can be found in the service The URI of the authorization endpoint can be found in the service
documentation, or can be obtained by the client by making an documentation, or can be obtained by the client by making an
unauthorized protected resource request (from the "WWW-Authenticate" unauthorized protected resource request (from the "WWW-Authenticate"
response header auth-uri (Section 6.1.2) attribute). response header auth-uri (Section 6.1.2) attribute).
The authorization endpoint advertised by the resource server MAY The authorization endpoint advertised by the resource server MAY
include a query components as defined by [RFC3986] section 3. include a query component as defined by [RFC3986] section 3.
Since requests to the authorization endpoint result in user Since requests to the authorization endpoint result in user
authentication and the transmission of sensitive values, the authentication and the transmission of sensitive values, 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 or SSL (or a secure channel with equivalent mechanism such as TLS/SSL (or a secure channel with equivalent
protections) when sending requests to the authorization endpoints. protections) when sending requests to the authorization endpoints.
3.2. Token Endpoint 3.2. Token Endpoint
After obtaining authorization from the resource owner, clients After obtaining authorization from the resource owner, clients
request an access token from the authorization server's token request an access token from the authorization server's token
endpoint. endpoint.
The URI of the token endpoint can be found in the service The URI of the token endpoint can be found in the service
documentation, or can be obtained by the client by making an documentation, or can be obtained by the client by making an
unauthorized protected resource request (from the "WWW-Authenticate" unauthorized protected resource request (from the "WWW-Authenticate"
response header token-uri (Section 6.1.2) attribute). response header token-uri (Section 6.1.2) attribute).
The token endpoint advertised by the resource server MAY include a The token endpoint advertised by the resource server MAY include a
query components as defined by [RFC3986] section 3. query component as defined by [RFC3986] section 3.
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 such as TLS or SSL (or a secure channel with equivalent mechanism such as TLS/SSL (or a secure channel with equivalent
protections) when sending requests to the token endpoints. protections) when sending requests to the token endpoints.
The authorization server MUST include the HTTP "Cache-Control" The authorization server MUST include the HTTP "Cache-Control"
response header field with a value of "no-store" in any response response header field with a value of "no-store" in any response
containing tokens, secrets, or other sensitive information. containing tokens, secrets, or other sensitive information.
3.3. Flow Parameters 3.3. Flow Parameters
Clients should avoid making assumptions about the size of tokens and The sizes of tokens and other values received from the authorization
other values received from the authorization server, which are left server, are left undefined by this specification. Clients should
undefined by this specification. Servers should document the avoid making assumptions about value sizes. Servers should document
expected size of any value they issue. the expected size of any value they issue.
Unless otherwise noted, all the protocol parameter names and values
are case sensitive.
3.4. Client Credentials 3.4. Client Credentials
When requesting access from the authorization server, the client When requesting access from the authorization server, the client
identifies itself using its authorization-server-issued client identifies itself using its authorization-server-issued client
credentials. The client credentials include a client identifier and credentials. The client credentials include a client identifier and
an OPTIONAL symmetric shared secret. The means through which the an OPTIONAL symmetric shared secret. The means through which the
client obtains these credentials are beyond the scope of this client obtains these credentials are beyond the scope of this
specification, but usually involve registration with the specification, but usually involve registration with the
authorization server. authorization server.
skipping to change at page 10, line 46 skipping to change at page 10, line 50
The client identifier is used by the authorization server to The client identifier is used by the authorization server to
establish the identity of the client for the purpose of presenting establish the identity of the client for the purpose of presenting
information to the resource owner prior to granting access, as well information to the resource owner prior to granting access, as well
as for providing different service levels to different clients. They as for providing different service levels to different clients. They
can also be used to block unauthorized clients from requesting can also be used to block unauthorized clients from requesting
access. access.
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 the client incapable or servers SHOULD NOT issue client secrets to clients incapable of
keeping their secrets confidential. keeping their secrets confidential.
3.5. User Delegation Flows 3.5. User Delegation Flows
User delegation flows are used to grant client access to protected User delegation flows are used to grant client access to protected
resources by the end user without sharing the end user credentials resources by the end-user without sharing the end-user credentials
(e.g. a username and password) with the client. Instead, the end (e.g. a username and password) with the client. Instead, the end-
user authenticates directly with the authorization server, and grants user authenticates directly with the authorization server, and grants
client access to its protected resources. client access to its protected resources.
3.5.1. User-Agent Flow 3.5.1. User-Agent Flow
The user-agent flow is a user delegation flow suitable for client The user-agent flow is a user delegation flow suitable for client
applications residing in a user-agent, typically implemented in a applications residing in a user-agent, typically implemented in a
browser using a scripting language such as JavaScript. The client is browser using a scripting language such as JavaScript. These clients
capable of interacting with the end user's user-agent but is cannot keep client secrets confidential and the authentication of the
incapable of receiving incoming requests from the authorization client is based on the user-agent's same-origin policy.
server (incapable of acting as an HTTP server).
Instead of receiving incoming requests, the client requests the Unlike other flows in which the client makes separate authorization
authorization server to redirect the user-agent to another web server and access token requests, the client received the access token as a
or local resource accessible to the browser which is capable of result of the authorization request in the form of an HTTP
extracting the access token from the response and passing it to the redirection. The client requests the authorization server to
client. redirect the user-agent to another web server or local resource
accessible to the browser which is capable of extracting the access
token from the response and passing it to the client.
This user-agent flow does not utilize the client secret since the This user-agent flow does not utilize the client secret since the
client executables reside on the end user's computer or device which client executables reside on the end-user's computer or device which
makes the client secret accessible and exploitable. Because the makes the client secret accessible and exploitable. Because the
client is incapable of receiving incoming requests, the access token access token is encoded into the redirection URI, it may be exposed
is encoded into the redirection URI which exposes it to the end user to the end-user and other applications residing on the computer or
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 Refresh Token) +----------------+ | in | (w/ Optional Refresh Token) +----------------+
| Browser | in Fragment | Browser | in Fragment
skipping to change at page 12, line 4 skipping to change at page 12, line 22
| in | (w/ Optional Refresh Token) +----------------+ | in | (w/ Optional Refresh Token) +----------------+
| Browser | in Fragment | Browser | in Fragment
| | +----------------+ | | +----------------+
| |>---(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 Figure 3
The user-agent flow illustrated in Figure 3 includes the following The user-agent flow illustrated in Figure 3 includes the following
steps: steps:
(A) The client sends the user-agent to the authorization server and (A) The client sends the user-agent to the authorization server and
includes its client identifier and redirection URI in the includes its client identifier and redirection URI in the
request. request.
(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 to the redirection URI provided redirects the user-agent to the redirection URI provided
earlier. The redirection URI includes the access token in the earlier. The redirection URI includes the access token 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 containing a script capable of (E) The web server returns a web page containing a script capable of
extracting the access token from the URI fragment retained by extracting the access token from the URI fragment retained by
the user-agent. the user-agent.
(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. which extracts the access token and passes it to the client.
3.5.1.1. Client Requests Authorization 3.5.1.1. Client Requests Authorization
In order for the end user to grant the client access, the client In order for the end-user to grant the client access, the client
sends the end user to the authorization server. The client sends the end-user to the authorization server. The client
constructs the request URI by adding the following URI query constructs the request URI by adding the following URI query
parameters to the user authorization endpoint URI: parameters to the user authorization endpoint URI:
type type
REQUIRED. The parameter value MUST be set to "user_agent" REQUIRED. The parameter value MUST be set to "user_agent".
(case sensitive).
client_id client_id
REQUIRED. The client identifier as described in Section 3.4. REQUIRED. The client identifier as described in Section 3.4.
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 SOULD require the client completed. The authorization server SHOULD require the client
to pre-register their redirection URI. The redirection URI to pre-register their redirection URI. The redirection URI
MUST NOT includes a query component as defined by [RFC3986] MUST NOT include a query component as defined by [RFC3986]
section 3 if the "state" parameter is present. section 3 if the "state" parameter is present.
state state
OPTIONAL. An opaque value used by the client to maintain state OPTIONAL. An opaque value used by the client to maintain state
between the request and callback. The authorization server between the request and callback. The authorization server
includes this value when redirecting the user-agent back to the includes this value when redirecting the user-agent back to the
client. client.
immediate immediate
OPTIONAL. The parameter value must be set to "true" or "false" OPTIONAL. The parameter value must be set to "true" or
(case sensitive). If set to "true", the authorization server "false". If set to "true", the authorization server MUST NOT
MUST NOT prompt the end user to authenticate or approve access. prompt the end-user to authenticate or approve access.
Instead, the authorization server attempts to establish the end Instead, the authorization server attempts to establish the
user's identity via other means (e.g. browser cookies) and end-user's identity via other means (e.g. browser cookies) and
checks if the end user has previously approved an identical checks if the end-user has previously approved an identical
access request by the same client and if that access grant is access request by the same client and if that access grant is
still active. If the authorization server does not support an still active. If the authorization server does not support an
immediate check or if it is unable to establish the end user's immediate check or if it is unable to establish the end-user's
identity or approval status, it MUST deny the request without identity or approval status, it MUST deny the request without
prompting the end user. Defaults to "false" if omitted. prompting the end-user. Defaults to "false" if omitted.
secret_type secret_type
OPTIONAL. The access token secret type as described by OPTIONAL. The access token secret type as described by
Section 5.3. If omitted, the authorization server will issue a Section 5.3. If omitted, the authorization server will issue a
bearer token (an access token without a matching secret) as bearer token (an access token without a matching secret) as
described by Section 5.2. described by Section 5.2.
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 HTTPS request (line breaks are for display purposes only):
GET /authorize?type=user_agent&client_id=s6BhdRkqt3& GET /authorize?type=user_agent&client_id=s6BhdRkqt3&
redirect_uri=https%3A%2F%2FEexample%2Ecom%2Frd HTTP/1.1 redirect_uri=https%3A%2F%2FEexample%2Ecom%2Frd 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. the client identifier.
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 establishing authorization decision (by asking the end-user or establishing
approval via other means). The authorization server sends the end approval via other means). The authorization server sends the end-
user's user-agent to the provided client redirection URI using an user's user-agent to the provided client redirection URI using an
HTTP redirection response. HTTP redirection response.
3.5.1.1.1. End User Grants Authorization 3.5.1.1.1. End-user Grants Authorization
If the end user authorizes the access request, the authorization If the end-user authorizes the access request, the authorization
server issues an access token and delivers it to the client by adding server issues an access token and delivers it to the client by adding
the following parameters, using the the following parameters, using the
"application/x-www-form-urlencoded" format as defined by "application/x-www-form-urlencoded" format as defined by
[W3C.REC-html40-19980424], to the redirection URI fragment: [W3C.REC-html40-19980424], to the redirection URI fragment:
access_token access_token
REQUIRED. The access token. REQUIRED. The access token.
expires_in expires_in
OPTIONAL. The duration in seconds of the access token OPTIONAL. The duration in seconds of the access token
skipping to change at page 14, line 36 skipping to change at page 15, line 14
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.
access_token_secret access_token_secret
REQUIRED if requested by the client. The corresponding access REQUIRED if requested by the client. The corresponding access
token secret as requested by the client. token secret as requested by the client.
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
3.5.1.1.2. End User Denies Authorization 3.5.1.1.2. End-user Denies Authorization
If the end user denied the access request, the authorization server If the end-user denied the access request, the authorization server
responds to the client by adding the following parameters, using the responds to the client by adding the following parameters, using the
"application/x-www-form-urlencoded" format as defined by "application/x-www-form-urlencoded" format as defined by
[W3C.REC-html40-19980424], to the redirection URI fragment: [W3C.REC-html40-19980424], to the redirection URI fragment:
error error
REQUIRED. The parameter value MUST be set to "user_denied" REQUIRED. The parameter value MUST be set to "user_denied".
(case sensitive).
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.
For example, the authorization server responds with the following: For example, the authorization server responds with the following:
HTTP/1.1 302 Found HTTP/1.1 302 Found
Location: http://example.com/rd#error=user_denied Location: http://example.com/rd#error=user_denied
skipping to change at page 15, line 46 skipping to change at page 16, line 21
The HTTP response to the redirection request returns a web page The HTTP response to the redirection request returns a web page
(typically an HTML page with an embedded script) capable of accessing (typically an HTML page with an embedded script) capable of accessing
the full redirection URI including the fragment retained by the user- the full redirection URI including the fragment retained by the user-
agent, and extracting the access token (and other parameters) agent, and extracting the access token (and other parameters)
contained in the fragment. contained in the fragment.
3.5.2. Web Server Flow 3.5.2. Web Server Flow
The web server flow is a user delegation flow suitable for clients The web server flow is a user delegation flow suitable for clients
capable of interacting with the end user's user-agent (typically a capable of interacting with the end-user's user-agent (typically a
web browser) and capable of receiving incoming requests from the web browser) and capable of receiving incoming requests from the
authorization server (capable of acting as an HTTP server). authorization server (capable of acting as an HTTP server).
+----------+ Client Identifier +---------------+ +----------+ Client Identifier +---------------+
| -+----(A)-- & Redirect URI ------->| | | -+----(A)-- & Redirect URI ------->| |
| End User | | Authorization | | End-user | | Authorization |
| at |<---(B)-- User authenticates --->| Server | | at |<---(B)-- User authenticates --->| Server |
| Browser | | | | Browser | | |
| -+----(C)-- Verification Code ----<| | | -+----(C)-- Verification Code ----<| |
+-|----|---+ +---------------+ +-|----|---+ +---------------+
| | ^ v | | ^ v
(A) (C) | | (A) (C) | |
| | | | | | | |
^ v | | ^ v | |
+---------+ | | +---------+ | |
| |>---(D)-- Client Credentials, --------' | | |>---(D)-- Client Credentials, --------' |
skipping to change at page 16, line 29 skipping to change at page 17, line 5
| Client | & Redirect URI | | Client | & Redirect URI |
| | | | | |
| |<---(E)------- Access Token -----------------' | |<---(E)------- Access Token -----------------'
+---------+ (w/ Optional Refresh Token) +---------+ (w/ Optional Refresh Token)
Figure 4 Figure 4
The web server flow illustrated in Figure 4 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 authorization endpoint with its client user-agent to the authorization endpoint with its client
identifier and a redirect URI to which the authorization server identifier and a redirect URI to which the authorization server
will send the end user back once authorization is received (or will send the end-user back once authorization is received (or
denied). 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 a verification URI provided earlier. The authorization includes a verification
code for the client to use to obtain an access token. code for the client to use to obtain an access token.
(D) The client requests an access token from the authorization (D) The client requests an access token from the authorization
server by including its client credentials (identifier and server by including its client credentials (identifier and
secret), as well as the verification code received in the secret), as well as the verification code received in the
previous step. previous step.
(E) The authorization server validates the client credentials and (E) The authorization server validates the client credentials and
the verification code and responds back with the access token. the verification code and responds back with the access token.
3.5.2.1. Client Requests Authorization 3.5.2.1. Client Requests Authorization
In order for the end user to grant the client access, the client In order for the end-user to grant the client access, the client
sends the end user to the authorization server. The client sends the end-user to the authorization server. The client
constructs the request URI by adding the following URI query constructs the request URI by adding the following URI query
parameters to the user authorization endpoint URI: parameters to the user authorization endpoint URI:
type type
REQUIRED. The parameter value MUST be set to "web_server" REQUIRED. The parameter value MUST be set to "web_server".
(case sensitive).
client_id client_id
REQUIRED. The client identifier as described in Section 3.4. REQUIRED. The client identifier as described in Section 3.4.
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 MAY require the client to completed. The authorization server MAY require the client to
pre-register their redirection URI. The redirection URI MUST pre-register their redirection URI. The redirection URI MUST
NOT includes a query component as defined by [RFC3986] section NOT include a query component as defined by [RFC3986] section 3
3 if the "state" parameter is present. if the "state" parameter is present.
state state
OPTIONAL. An opaque value used by the client to maintain state OPTIONAL. An opaque value used by the client to maintain state
between the request and callback. The authorization server between the request and callback. The authorization server
includes this value when redirecting the user-agent back to the includes this value when redirecting the user-agent back to the
client. client.
immediate immediate
OPTIONAL. The parameter value must be set to "true" or "false" OPTIONAL. The parameter value must be set to "true" or
(case sensitive). If set to "true", the authorization server "false". If set to "true", the authorization server MUST NOT
MUST NOT prompt the end user to authenticate or approve access. prompt the end-user to authenticate or approve access.
Instead, the authorization server attempts to establish the end Instead, the authorization server attempts to establish the
user's identity via other means (e.g. browser cookies) and end-user's identity via other means (e.g. browser cookies) and
checks if the end user has previously approved an identical checks if the end-user has previously approved an identical
access request by the same client and if that access grant is access request by the same client and if that access grant is
still active. If the authorization server does not support an still active. If the authorization server does not support an
immediate check or if it is unable to establish the end user's immediate check or if it is unable to establish the end-user's
identity or approval status, it MUST deny the request without identity or approval status, it MUST deny the request without
prompting the end user. Defaults to "false" if omitted. prompting the end-user. Defaults to "false" if omitted.
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 requests (line breaks are for display purposes only): following HTTPS requests (line breaks are for display purposes only):
GET /authorize?type=web_server&client_id=s6BhdRkqt3&redirect_uri= GET /authorize?type=web_server&client_id=s6BhdRkqt3&redirect_uri=
https%3A%2F%2Fclient%2Eexample%2Ecom%2Fcb HTTP/1.1 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. the client identifier.
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 establishing authorization decision (by asking the end-user or establishing
approval via other means). The authorization server sends the end approval via other means). The authorization server sends the end-
user's user-agent to the provided client redirection URI using an user's user-agent to the provided client redirection URI using an
HTTP redirection response, or by other means available to it via the HTTP redirection response, or by other means available to it via the
end user's user-agent. end-user's user-agent.
3.5.2.1.1. End User Grants Authorization 3.5.2.1.1. End-user Grants Authorization
If the end user authorizes the access request, the authorization If the end-user authorizes the access request, the authorization
server generates a verification code and associates it with the server generates a verification code and associates it with the
client identifier and redirection URI. The authorization server client identifier and redirection URI. The authorization server
constructs the request URI by adding the following parameters to the constructs the request URI by adding the following parameters to the
query component of redirection URI provided by the client: query component of redirection URI provided by the client:
code code
REQUIRED. The verification code generated by the authorization REQUIRED. The verification code generated by the authorization
server. server.
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 verification code SHOULD expire shortly after it is issued and The verification code should expire shortly after it is issued and
allowed for a single use. allowed for a single use.
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
In turn, the end user's user-agent makes the following HTTPS "GET" In turn, the end-user's user-agent makes the following HTTPS "GET"
request: request:
GET /cb?code=i1WsRn1uB1 HTTP/1.1 GET /cb?code=i1WsRn1uB1 HTTP/1.1
Host: client.example.com Host: client.example.com
3.5.2.1.2. End User Denies Authorization 3.5.2.1.2. End-user Denies Authorization
If the end user denied the access request, the authorization server If the end-user denied the access request, the authorization server
constructs the request URI by adding the following parameters to the constructs the request URI by adding the following parameters to the
query component of the redirection URI provided by the client: query component of the redirection URI provided by the client:
error error
REQUIRED. The parameter value MUST be set to "user_denied" REQUIRED. The parameter value MUST be set to "user_denied".
(case sensitive).
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.
For example, the authorization server directs the client to make the For example, the authorization server directs the client to make the
following HTTP request: following HTTP request:
GET /cb?error=user_denied HTTP/1.1 GET /cb?error=user_denied HTTP/1.1
skipping to change at page 19, line 42 skipping to change at page 20, line 15
The authorization flow concludes unsuccessfully. The authorization flow concludes unsuccessfully.
3.5.2.2. Client Requests Access Token 3.5.2.2. Client Requests Access Token
The client obtains an access token from the authorization server by The client obtains an access token from the authorization server by
making an HTTP "POST" request to the token endpoint. The client making an HTTP "POST" request to the token endpoint. The client
constructs a request URI by adding the following parameters to the constructs a request URI by adding the following parameters to the
request: request:
type type
REQUIRED. The parameter value MUST be set to "web_server" REQUIRED. The parameter value MUST be set to "web_server".
(case sensitive).
client_id client_id
REQUIRED. The client identifier as described in Section 3.4. REQUIRED. The client identifier as described in Section 3.4.
client_secret client_secret
REQUIRED if the client identifier has a matching secret. The REQUIRED if the client identifier has a matching secret. The
client secret as described in Section 3.4. client secret as described in Section 3.4.
code code
REQUIRED. The verification code received from the REQUIRED. The verification code received from the
skipping to change at page 21, line 7 skipping to change at page 21, line 19
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.
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 Section 4. using the same end-user access grant as described in Section 4.
access_token_secret access_token_secret
REQUIRED if requested by the client. The corresponding access REQUIRED if requested by the client. The corresponding access
token secret as requested by the client. token secret as requested by the client.
For example: For example:
HTTP/1.1 200 OK HTTP/1.1 200 OK
Content-Type: application/x-www-form-urlencoded Content-Type: application/x-www-form-urlencoded
skipping to change at page 21, line 29 skipping to change at page 21, line 41
If the request is invalid, the authorization server returns an error If the request is invalid, the authorization server returns an error
message in the HTTP response body using the message in the HTTP response body using the
"application/x-www-form-urlencoded" content type as defined by "application/x-www-form-urlencoded" content type as defined by
[W3C.REC-html40-19980424] with a 400 status code (Bad Request). [W3C.REC-html40-19980424] with a 400 status code (Bad Request).
The response contains the following parameter: The response contains the following parameter:
error error
OPTIONAL. The parameter value MUST be set to either OPTIONAL. The parameter value MUST be set to either
"redirect_uri_mismatch" or "expired_verification_code" (case "redirect_uri_mismatch", "bad_verification_code",
sensitive). "incorrect_client_credentials".
For example: For example:
HTTP/1.1 400 Bad Request HTTP/1.1 400 Bad Request
Content-Type: application/x-www-form-urlencoded Content-Type: application/x-www-form-urlencoded
error=expired_verification_code error=bad_verification_code
3.5.3. Device Flow 3.5.3. Device Flow
The device flow is a user delegation flow suitable for clients The device flow is a user delegation flow suitable for clients
executing on devices which do not have an easy data-entry method executing on devices which do not have an easy data-entry method
(e.g. game consoles or media hub), but where the end user has (e.g. game consoles or media hub), but where the end-user has
separate access to a user-agent on another computer or device (e.g. separate access to a user-agent on another computer or device (e.g.
home computer, a laptop, or a smartphone). The client is incapable home computer, a laptop, or a smartphone). The client is incapable
of receiving incoming requests from the authorization server of receiving incoming requests from the authorization server
(incapable of acting as an HTTP server). (incapable of acting as an HTTP server).
Instead of interacting with the end user's user-agent, the client Instead of interacting with the end-user's user-agent, the client
instructs the end user to use another computer or device and connect instructs the end-user to use another computer or device and connect
to the authorization server to approve the access request. Since the to the authorization server to approve the access request. Since the
client cannot receive incoming requests, it polls the authorization client cannot receive incoming requests, it polls the authorization
server repeatedly until the end user completes the approval process. server repeatedly until the end-user completes the approval process.
This device flow does not utilize the client secret since the client This device flow does not utilize the client secret since the client
executables reside on a local device which makes the client secret executables reside on a local device which makes the client secret
accessible and exploitable. accessible and exploitable.
+----------+ +----------------+ +----------+ +----------------+
| |>---(A)-- Client Identifier --->| | | |>---(A)-- Client Identifier --->| |
| | | | | | | |
| |<---(B)-- Verification Code, --<| | | |<---(B)-- Verification Code, --<| |
| | User Code, | | | | User Code, | |
skipping to change at page 22, line 32 skipping to change at page 22, line 45
| |>---(E)---> | | | |>---(E)---> | |
| | | Authorization | | | | Authorization |
| |<---(F)-- Access Token --------<| Server | | |<---(F)-- Access Token --------<| Server |
+----------+ (w/ Optional Refresh Token) | | +----------+ (w/ Optional Refresh Token) | |
v | | v | |
: | | : | |
(C) User Code & Verification URI | | (C) User Code & Verification URI | |
: | | : | |
v | | v | |
+----------+ | | +----------+ | |
| End User | | | | End-user | | |
| at |<---(D)-- User authenticates -->| | | at |<---(D)-- User authenticates -->| |
| Browser | | | | Browser | | |
+----------+ +----------------+ +----------+ +----------------+
Figure 5 Figure 5
The device flow illustrated in Figure 5 includes the following steps: The device flow illustrated in Figure 5 includes the following steps:
(A) The client requests access from the authorization server and (A) The client requests access from the authorization server and
includes its client identifier in the request. includes its client identifier in the request.
(B) The authorization server issues a verification code, a user (B) The authorization server issues a verification code, a user
code, and provides the end user authorization URI. code, and provides the end-user authorization URI.
(C) The client instructs the end user to use its user-agent (C) The client instructs the end-user to use its user-agent
(elsewhere) and visit the provided authorization URI. The (elsewhere) and visit the provided authorization URI. The
client provides the user with the user code to enter in order to client provides the user with the user code to enter in order to
grant access. grant access.
(D) The authorization server authenticates the end user (via the (D) The authorization server authenticates the end-user (via the
user-agent) and prompts the end user to grant the client's user-agent) and prompts the end-user to grant the client's
access request by entering the user code provided by the client. access request by entering the user code provided by the client.
(E) While the end user authorizes (or denies) the client's request (E) While the end-user authorizes (or denies) the client's request
(D), the client repeatedly polls the authorization server to (D), the client repeatedly polls the authorization server to
find out if the end user completed the user authorization step. find out if the end-user completed the user authorization step.
The client includes the verification code and its client The client includes the verification code and its client
identifier. identifier.
(F) Assuming the end user granted access, the authorization server (F) Assuming the end-user granted access, the authorization server
validates the verification code provided by the client and validates the verification code provided by the client and
responds back with the access token. responds back with the access token.
3.5.3.1. Client Requests Authorization 3.5.3.1. Client Requests Authorization
The client initiates the flow by requesting a set of verification The client initiates the flow by requesting a set of verification
codes from the authorization server by making an HTTP "GET" request codes from the authorization server by making an HTTP "GET" request
to the authorization endpoint. The client constructs a request URI to the token endpoint. The client constructs a request URI by adding
by adding the following parameters to the request: the following parameters to the request:
type type
REQUIRED. The parameter value MUST be set to 'device' (case REQUIRED. The parameter value MUST be set to "device_code".
sensitive).
client_id client_id
REQUIRED. The client identifier as described in Section 3.4. REQUIRED. The client identifier as described in Section 3.4.
For example, the client makes the following HTTPS request (line For example, the client makes the following HTTPS request (line
breaks are for display purposes only): breaks are for display purposes only):
GET /authorize?type=device&client_id=s6BhdRkqt3 GET /token?type=device_code&client_id=s6BhdRkqt3
HTTP/1.1 HTTP/1.1
Host: server.example.com Host: server.example.com
In response, the authorization server generates a verification code In response, the authorization server generates a verification code
and a user code and includes them in the HTTP response body using the and a user code and includes them in the HTTP response body using the
"application/x-www-form-urlencoded" format as defined by "application/x-www-form-urlencoded" format as defined by
[W3C.REC-html40-19980424] with a 200 status code (OK). The response [W3C.REC-html40-19980424] with a 200 status code (OK). The response
contains the following parameters: contains the following parameters:
code code
skipping to change at page 24, line 26 skipping to change at page 24, line 35
interval interval
OPTIONAL. The minimum amount of time in seconds that the OPTIONAL. The minimum amount of time in seconds that the
client SHOULD wait between polling requests to the token client SHOULD wait between polling requests to the token
endpoint. endpoint.
For example (line breaks are for display purposes only): For example (line breaks are for display purposes only):
HTTP/1.1 200 OK HTTP/1.1 200 OK
Content-Type: application/x-www-form-urlencoded Content-Type: application/x-www-form-urlencoded
device_code=74tq5miHKB&user_code=94248&user_uri=http%3A%2F%2 code=74tq5miHKB&user_code=94248&user_uri=http%3A%2F%2
Fwww%2Eexample%2Ecom%2Fdevice&interval=5 Fwww%2Eexample%2Ecom%2Fdevice&interval=5
The client displays the user code and the user authorization URI to The client displays the user code and the user authorization URI to
the end-user, and instructs the end user to visit the URI using a the end-user, and instructs the end-user to visit the URI using a
user-agent and enter the user code. user-agent and enter the user code.
The end user manually types the provided URI and authenticates with The end-user manually types the provided URI and authenticates with
the authorization server. The authorization server prompts the end the authorization server. The authorization server prompts the end-
user to authorize the client's request by entering the user code user to authorize the client's request by entering the user code
provided by the client. Once the end user approves or denies the provided by the client. Once the end-user approves or denies the
request, the authorization server informs the end user to return to request, the authorization server informs the end-user to return to
the device for further instructions. the device for further instructions.
3.5.3.2. Client Requests Access Token 3.5.3.2. Client Requests Access Token
Since the client is unable to receive incoming requests from the Since the client is unable to receive incoming requests from the
authorization server, it polls the authorization server repeatedly authorization server, it polls the authorization server repeatedly
until the end user grants or denies the request, or the verification until the end-user grants or denies the request, or the verification
code expires. code expires.
The client makes the following request at an arbitrary but reasonable The client makes the following request at an arbitrary but reasonable
interval which MUST NOT exceed the minimum interval rate provided by interval which MUST NOT exceed the minimum interval rate provided by
the authorization server (if present via the "interval" parameter). the authorization server (if present via the "interval" parameter).
Alternatively, the client MAY provide a user interface for the end Alternatively, the client MAY provide a user interface for the end-
user to manually inform it when authorization was granted. user to manually inform it when authorization was granted.
The client requests an access token by making an HTTP "GET" request The client requests an access token by making an HTTP "GET" request
to the token endpoint. The client constructs a request URI by adding to the token endpoint. The client constructs a request URI by adding
the following parameters to the request: the following parameters to the request:
type type
REQUIRED. The parameter value MUST be set to 'device' (case REQUIRED. The parameter value MUST be set to "device_token".
sensitive).
client_id client_id
REQUIRED. The client identifier as described in Section 3.4. REQUIRED. The client identifier as described in Section 3.4.
code code
The verification code received from the authorization server. The verification code received from the authorization server.
secret_type secret_type
OPTIONAL. The access token secret type as described by OPTIONAL. The access token secret type as described by
Section 5.3. If omitted, the authorization server will issue a Section 5.3. If omitted, the authorization server will issue a
bearer token (an access token without a matching secret) as bearer token (an access token without a matching secret) as
described by Section 5.2. described by Section 5.2.
For example, the client makes the following HTTPS request (line For example, the client makes the following HTTPS request (line
breaks are for display purposes only): breaks are for display purposes only):
GET /token?type=device&client_id=s6BhdRkqt3 GET /token?type=device_token&client_id=s6BhdRkqt3
&code=J2vC42OifV HTTP/1.1 &code=J2vC42OifV HTTP/1.1
Host: server.example.com Host: server.example.com
3.5.3.2.1. End User Grants Authorization 3.5.3.2.1. End-user Grants Authorization
If the end user authorized the request, the authorization server If the end-user authorized the request, the authorization server
issues an access token and delivers it to the client by including it issues an access token and delivers it to the client by including it
in the HTTP response body using the in the HTTP response body using the
"application/x-www-form-urlencoded" content type as defined by "application/x-www-form-urlencoded" content type as defined by
[W3C.REC-html40-19980424] with a 200 status code (OK). The response [W3C.REC-html40-19980424] with a 200 status code (OK). The response
contains the following parameters: contains the following parameters:
access_token access_token
REQUIRED. The access token. REQUIRED. The access token.
expires_in expires_in
skipping to change at page 26, line 16 skipping to change at page 26, line 26
REQUIRED if requested by the client. The corresponding access REQUIRED if requested by the client. The corresponding access
token secret as requested by the client. token secret as requested by the client.
For example: For example:
HTTP/1.1 200 OK HTTP/1.1 200 OK
Content-Type: application/x-www-form-urlencoded Content-Type: application/x-www-form-urlencoded
access_token=FJQbwq9OD8&expires_in=3600 access_token=FJQbwq9OD8&expires_in=3600
3.5.3.2.2. End User Denies Authorization 3.5.3.2.2. End-user Denies Authorization
If the end user denied the request, the authorization server provides If the end-user denied the request, the authorization server provides
the client with the error message in the HTTP response body using the the client with the error message in the HTTP response body using the
"application/x-www-form-urlencoded" content type as defined by "application/x-www-form-urlencoded" content type as defined by
[W3C.REC-html40-19980424] with a 400 status code (Bad Request). The [W3C.REC-html40-19980424] with a 400 status code (Bad Request). The
response contains the following parameters: response contains the following parameters:
error error
REQUIRED. Value must be set to "authorization_declined". REQUIRED. Value must be set to "authorization_declined".
For example: For example:
HTTP/1.1 400 Bad Request HTTP/1.1 400 Bad Request
Content-Type: application/x-www-form-urlencoded Content-Type: application/x-www-form-urlencoded
error=authorization_declined error=authorization_declined
3.5.3.2.3. End User Authorization Pending or Expired 3.5.3.2.3. End-user Authorization Pending or Expired
If the end user authorization is pending or expired without receiving If the end-user authorization is pending or expired without receiving
any response from the end user, or the client is exceeding the any response from the end-user, or the client is exceeding the
allowed polling interval, the authorization server provides the allowed polling interval, the authorization server provides the
client with the error message in the HTTP response body using the client with the error message in the HTTP response body using the
"application/x-www-form-urlencoded" content type as defined by "application/x-www-form-urlencoded" content type as defined by
[W3C.REC-html40-19980424] with a 400 status code (Bad Request). The [W3C.REC-html40-19980424] with a 400 status code (Bad Request). The
response contains the following parameters: response contains the following parameters:
error error
REQUIRED. Value MUST be set to "authorization_pending", REQUIRED. Value MUST be set to "authorization_pending",
"slow_down", or "code_expired" (case sensitive). "slow_down", or "code_expired".
For example: For example:
HTTP/1.1 400 Bad Request HTTP/1.1 400 Bad Request
Content-Type: application/x-www-form-urlencoded Content-Type: application/x-www-form-urlencoded
error=authorization_pending error=authorization_pending
3.6. End User Credentials Flows 3.6. End-user Credentials Flows
End user credential flows are used to grant client access to End-user credential flows are used to grant client access to
protected resources by the end user directly sharing the end user protected resources by the end-user directly sharing the end-user's
credentials (typically a username and password) with the client. username and password with the client. Unlike user delegation flows,
Unlike user delegation flows, end user credentials flows require a end-user credentials flows require a much higher degree of trust
much higher degree of trust between the client and end user. between the client and end-user.
These flows are suitable in cases where the end user already has a These flows are suitable in cases where the end-user already has a
trust relationship with the client, such as its computer operating trust relationship with the client, such as its computer operating
system or highly privileged applications. Authorization servers system or highly privileged applications. Authorization servers
SHOULD take special care when enabling user credentials flows, and SHOULD take special care when enabling user credentials flows, and
SHOULD only do so when other delegation flows are not viable. SHOULD only do so when other delegation flows are not viable.
However, unlike the HTTP Basic authentication scheme defined in However, unlike the HTTP Basic authentication scheme defined in
[RFC2617], the end user's credentials are used in a single request [RFC2617], the end-user's credentials are used in a single request
and are exchanged for an access token and refresh token which and are exchanged for an access token and refresh token which
eliminates the client need to store them for future use. eliminates the client need to store them for future use.
3.6.1. Username and Password Flow 3.6.1. Username and Password Flow
The username and password flow is an end user credentials flow The username and password flow is an end-user credentials flow
suitable for clients capable of asking end users for their usernames suitable for clients capable of asking end users for their usernames
and passwords. It is also used to migrate existing clients using and passwords. It is also used to migrate existing clients using
direct authentication schemes such as HTTP Basic or Digest direct authentication schemes such as HTTP Basic or Digest
authentication to OAuth by converting the end user credentials stored authentication to OAuth by converting the end-user credentials stored
with tokens. with tokens.
The methods through which the client prompts end users for their The methods through which the client prompts end users for their
usernames and passwords is beyond the scope of this specification. usernames and passwords is beyond the scope of this specification.
The client MUST discard the usernames and passwords once an access The client MUST discard the usernames and passwords once an access
token has been obtained. token has been obtained.
End User End-user
v v
: :
(A) (A)
: :
v v
+--------+ +---------------+ +--------+ +---------------+
| | Client Credentials | | | | Client Credentials | |
| |>--(B)--- & User Credentials ---->| Authorization | | |>--(B)--- & User Credentials ---->| Authorization |
| Client | | Server | | Client | | Server |
| |<--(C)---- Access Token ---------<| | | |<--(C)---- Access Token ---------<| |
| | (w/ Optional Refresh Token) | | | | (w/ Optional Refresh Token) | |
+--------+ +---------------+ +--------+ +---------------+
Figure 6 Figure 6
The username and password flow illustrated in Figure 6 includes the The username and password flow illustrated in Figure 6 includes the
following steps: following steps:
(A) The end user provides the client with its username and password. (A) The end-user provides the client with its username and password.
(B) The client sends an access token request to the authorization (B) The client sends an access token request to the authorization
server and includes its client identifier and client secret, and server and includes its client identifier and client secret, and
the end user's username and password. the end-user's username and password.
(C) The authorization server validates the end user credentials and (C) The authorization server validates the end-user credentials and
the client credentials and issues an access token. the client credentials and issues an access token.
3.6.1.1. Client Requests Access Token 3.6.1.1. Client Requests Access Token
The client requests an access token by making an HTTP "POST" request The client requests an access token by making an HTTP "POST" request
to the token endpoint. The client constructs a request URI by adding to the token endpoint. The client constructs a request URI by adding
the following parameters to the request: the following parameters to the request:
type type
REQUIRED. The parameter value MUST be set to 'username' (case REQUIRED. The parameter value MUST be set to "username".
sensitive).
client_id client_id
REQUIRED. The client identifier as described in Section 3.4. REQUIRED. The client identifier as described in Section 3.4.
client_secret client_secret
REQUIRED. The client secret as described in Section 3.4. REQUIRED. The client secret as described in Section 3.4.
OPTIONAL if no client secret was issued. OPTIONAL if no client secret was issued.
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.
secret_type secret_type
OPTIONAL. The access token secret type as described by OPTIONAL. The access token secret type as described by
Section 5.3. If omitted, the authorization server will issue a Section 5.3. If omitted, the authorization server will issue a
bearer token (an access token without a matching secret) as bearer token (an access token without a matching secret) as
described by Section 5.2. described by Section 5.2.
For example, the client makes the following HTTPS request (line For example, the client makes the following HTTPS request (line
breaks are for display purposes only): breaks are for display purposes only):
POST /token HTTP/1.1 POST /token HTTP/1.1
Host: server.example.com Host: server.example.com
type=username&client_id=s6BhdRkqt3&client_secret= type=username&client_id=s6BhdRkqt3&client_secret=
47HDu8s&username=johndoe&password=A3ddj3w 47HDu8s&username=johndoe&password=A3ddj3w
The authorization server MUST validate the client credentials and end The authorization server MUST validate the client credentials and
user credentials and if valid issue an access token and deliver to end-user credentials and if valid issue an access token and deliver
the client in the HTTP response body using the to the client in the HTTP response body using the
"application/x-www-form-urlencoded" content type as defined by "application/x-www-form-urlencoded" content type as defined by
[W3C.REC-html40-19980424] with a 200 status code (OK). [W3C.REC-html40-19980424] with a 200 status code (OK).
The response contains the following parameters: The response contains the following parameters:
access_token access_token
REQUIRED. The access token. REQUIRED. The access token.
expires_in expires_in
OPTIONAL. The duration in seconds of the access token OPTIONAL. The duration in seconds of the access token
skipping to change at page 30, line 21 skipping to change at page 30, line 21
If the request is invalid, the authorization server returns an error If the request is invalid, the authorization server returns an error
message in the HTTP response body using the message in the HTTP response body using the
"application/x-www-form-urlencoded" content type as defined by "application/x-www-form-urlencoded" content type as defined by
[W3C.REC-html40-19980424] with a 400 status code (Bad Request). [W3C.REC-html40-19980424] with a 400 status code (Bad Request).
The response contains the following parameter: The response contains the following parameter:
error error
OPTIONAL. The parameter value MUST be set to either OPTIONAL. The parameter value MUST be set to either
"incorrect_credentials" or "unauthorized_client" (case "incorrect_client_credentials" or "unauthorized_client" (the
sensitive). client is not permitted to use this flow).
For example: For example:
HTTP/1.1 400 Bad Request HTTP/1.1 400 Bad Request
Content-Type: application/x-www-form-urlencoded Content-Type: application/x-www-form-urlencoded
error=incorrect_credentials error=incorrect_client_credentials
3.7. Autonomous Client Flows 3.7. Autonomous Client Flows
Autonomous client flows are used to grant client access to protected Autonomous client flows are used to grant client access to protected
resources controlled by the client (i.e. the client is the resource resources controlled by the client (i.e. the client is the resource
owner). For example, these flows are useful when a service provides owner). For example, these flows are useful when a service provides
both client-specific resources in addition to end user resources. both client-specific resources in addition to end-user resources.
3.7.1. Client Credentials Flow 3.7.1. Client Credentials Flow
The client credentials flow is used when the client acts autonomously The client credentials flow is used when the client acts autonomously
without acting on behalf of a separate resource owner. The client without acting on behalf of a separate resource owner. The client
secret is assumed to be high-entropy since it is not designed to be secret is assumed to be high-entropy since it is not designed to be
memorize by an end user. memorized by an end-user.
+--------+ +---------------+ +--------+ +---------------+
| | | | | | | |
| |>--(A)--- Client Credentials ---->| Authorization | | |>--(A)--- Client Credentials ---->| Authorization |
| Client | | Server | | Client | | Server |
| |<--(B)---- Access Token ---------<| | | |<--(B)---- Access Token ---------<| |
| | (w/ Optional Refresh Token) | | | | (w/ Optional Refresh Token) | |
+--------+ +---------------+ +--------+ +---------------+
Figure 7 Figure 7
skipping to change at page 31, line 31 skipping to change at page 31, line 31
(B) The authorization server validates the client credentials and (B) The authorization server validates the client credentials and
issues an access token. issues an access token.
3.7.1.1. Client Requests Access Token 3.7.1.1. Client Requests Access Token
The client requests an access token by making an HTTP "POST" request The client requests an access token by making an HTTP "POST" request
to the token endpoint. The client constructs a request URI by adding to the token endpoint. The client constructs a request URI by adding
the following parameters to the request: the following parameters to the request:
type type
REQUIRED. The parameter value MUST be set to 'client_cred' REQUIRED. The parameter value MUST be set to
(case sensitive). "client_credentials".
client_id client_id
REQUIRED. The client identifier as described in Section 3.4. REQUIRED. The client identifier as described in Section 3.4.
client_secret client_secret
REQUIRED. The client secret as described in Section 3.4. REQUIRED. The client secret as described in Section 3.4.
secret_type secret_type
OPTIONAL. The access token secret type as described by OPTIONAL. The access token secret type as described by
Section 5.3. If omitted, the authorization server will issue a Section 5.3. If omitted, the authorization server will issue a
bearer token (an access token without a matching secret) as bearer token (an access token without a matching secret) as
described by Section 5.2. described by Section 5.2.
For example, the client makes the following HTTPS request (line For example, the client makes the following HTTPS request (line
breaks are for display purposes only): breaks are for display purposes only):
POST /token HTTP/1.1 POST /token HTTP/1.1
Host: server.example.com Host: server.example.com
type=client_cred&client_id=s6BhdRkqt3&client_secret=47HDu8s type=client_credentials&client_id=s6BhdRkqt3&client_secret=47HDu8s
The authorization server MUST validate the client credentials and if The authorization server MUST validate the client credentials and if
valid issue an access token and deliver to the client in the HTTP valid issue an access token and deliver to the client in the HTTP
response body using the "application/x-www-form-urlencoded" content response body using the "application/x-www-form-urlencoded" content
type as defined by [W3C.REC-html40-19980424] with a 200 status code type as defined by [W3C.REC-html40-19980424] with a 200 status code
(OK). (OK).
The response contains the following parameters: The response contains the following parameters:
access_token access_token
skipping to change at page 33, line 6 skipping to change at page 33, line 6
access_token=FJQbwq9OD8 access_token=FJQbwq9OD8
If the request is invalid, the authorization server returns an error If the request is invalid, the authorization server returns an error
message in the HTTP response body using the message in the HTTP response body using the
"application/x-www-form-urlencoded" content type as defined by "application/x-www-form-urlencoded" content type as defined by
[W3C.REC-html40-19980424] with a 400 status code (Bad Request). [W3C.REC-html40-19980424] with a 400 status code (Bad Request).
The response contains the following parameter: The response contains the following parameter:
error error
OPTIONAL. The parameter value MUST be set to either OPTIONAL. The parameter value MUST be set to
"incorrect_credentials" or "unauthorized_client" (case "incorrect_client_credentials".
sensitive).
For example: For example:
HTTP/1.1 400 Bad Request HTTP/1.1 400 Bad Request
Content-Type: application/x-www-form-urlencoded Content-Type: application/x-www-form-urlencoded
error=incorrect_credentials error=incorrect_client_credentials
3.7.2. Assertion Flow 3.7.2. Assertion Flow
The assertion flow requires the client to obtain a assertion such as The assertion flow is used when a client wishes to exchange an
a SAML [OASIS.saml-core-2.0-os] assertion from an assertion issuer existing security token or assertion for an access token. This flow
prior to initiating the flow. The process in which the assertion is is suitable when the client is acting autonomously or on behalf of
obtained is defined by the assertion issuer and the authorization the end-user (based on the content of the assertion used).
server, and is beyond the scope of this specification.
The assertion flow requires the client to obtain a assertion (such as
a SAML [OASIS.saml-core-2.0-os] assertion) from an assertion issuer
or to self-issue an assertion prior to initiating the flow. The
assertion format, the process by which the assertion is obtained, and
the method of validating the assertion are defined by the assertion
issuer and the authorization server, and are beyond the scope of this
specification.
The client credentials flow is used when the client acts autonomously The client credentials flow is used when the client acts autonomously
without acting on behalf of a separate resource owner. without acting on behalf of a separate resource owner.
+--------+ +---------------+ +--------+ +---------------+
| | | | | | | |
| |>--(A)------ Assertion ---------->| Authorization | | |>--(A)------ Assertion ---------->| Authorization |
| Client | | Server | | Client | | Server |
| |<--(B)---- Access Token ---------<| | | |<--(B)---- Access Token ---------<| |
| | (w/ Optional Refresh Token) | | | | | |
+--------+ +---------------+ +--------+ +---------------+
Figure 8 Figure 8
The client credential flow illustrated in Figure 8 includes the The client credential flow illustrated in Figure 8 includes the
following steps: following steps:
(A) The client sends an access token request to the authorization (A) The client sends an access token request to the authorization
server and includes an assertion. server and includes an assertion.
(B) The authorization server validates the assertion and issues an (B) The authorization server validates the assertion and issues an
access token. access token.
3.7.2.1. Client Requests Access Token 3.7.2.1. Client Requests Access Token
The client requests an access token by making an HTTP "POST" request The client requests an access token by making an HTTP "POST" request
to the token endpoint. The client constructs a request URI by adding to the token endpoint. The client constructs a request URI by adding
the following parameters to the request: the following parameters to the request:
type type
REQUIRED. The parameter value MUST be set to 'assertion' (case REQUIRED. The parameter value MUST be set to "assertion".
sensitive).
format format
REQUIRED. The format of the assertion as defined by the REQUIRED. The format of the assertion as defined by the
authorization server. authorization server. The value MUST be an absolute URI.
assertion assertion
REQUIRED. The assertion. REQUIRED. The assertion.
secret_type secret_type
OPTIONAL. The access token secret type as described by OPTIONAL. The access token secret type as described by
Section 5.3. If omitted, the authorization server will issue a Section 5.3. If omitted, the authorization server will issue a
bearer token (an access token without a matching secret) as bearer token (an access token without a matching secret) as
described by Section 5.2. described by Section 5.2.
skipping to change at page 35, line 5 skipping to change at page 35, line 9
The response contains the following parameters: The response contains the following parameters:
access_token access_token
REQUIRED. The access token. REQUIRED. The access token.
expires_in expires_in
OPTIONAL. The duration in seconds of the access token OPTIONAL. The duration in seconds of the access token
lifetime. lifetime.
refresh_token
OPTIONAL. The refresh token.
access_token_secret access_token_secret
REQUIRED if requested by the client. The corresponding access REQUIRED if requested by the client. The corresponding access
token secret as requested by the client. token secret as requested by the client.
For example: For example:
HTTP/1.1 200 OK HTTP/1.1 200 OK
Content-Type: application/x-www-form-urlencoded Content-Type: application/x-www-form-urlencoded
access_token=FJQbwq9OD8 access_token=FJQbwq9OD8
If the assertion is invalid, the authorization server returns an If the assertion is invalid, the authorization server returns an
error message in the HTTP response body using the error message in the HTTP response body using the
"application/x-www-form-urlencoded" content type as defined by "application/x-www-form-urlencoded" content type as defined by
[W3C.REC-html40-19980424] with a 400 status code (Bad Request). [W3C.REC-html40-19980424] with a 400 status code (Bad Request).
The response contains the following parameter: The response contains the following parameter:
error error
OPTIONAL. The parameter value MUST be set to either OPTIONAL. The parameter value MUST be set to either
"invalid_assertion" or "unknown_format" (case sensitive). "invalid_assertion" or "unknown_format".
For example: For example:
HTTP/1.1 400 Bad Request HTTP/1.1 400 Bad Request
Content-Type: application/x-www-form-urlencoded Content-Type: application/x-www-form-urlencoded
error=incorrect_credentials error=incorrect_credentials
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
skipping to change at page 36, line 21 skipping to change at page 36, line 23
+--------+ +---------------+ +--------+ +---------------+
Figure 9 Figure 9
To refresh a token, the client constructs an HTTP "POST" request to To refresh a token, the client constructs an HTTP "POST" request to
the token endpoint and includes the following parameters in the HTTP the token endpoint and includes the following parameters in the HTTP
request body using the "application/x-www-form-urlencoded" content request body using the "application/x-www-form-urlencoded" content
type as defined by [W3C.REC-html40-19980424]: type as defined by [W3C.REC-html40-19980424]:
type type
REQUIRED. The parameter value MUST be set to 'refresh' (case REQUIRED. The parameter value MUST be set to "refresh".
sensitive).
client_id client_id
REQUIRED. The client identifier as described in Section 3.4. REQUIRED. The client identifier as described in Section 3.4.
client_secret client_secret
REQUIRED if the client was issued a secret. The client secret. REQUIRED if the client was issued a secret. The client secret.
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.
secret_type secret_type
OPTIONAL. The access token secret type as described by OPTIONAL. The access token secret type as described by
Section 5.3. If omitted, the authorization server will issue a Section 5.3. If omitted, the authorization server will issue a
bearer token (an access token without a matching secret) as bearer token (an access token without a matching secret) as
described by Section 5.2. described by Section 5.2.
For example, the client makes the following HTTPS request (line break For example, the client makes the following HTTPS request (line break
are for display purposes only): are for display purposes only):
POST /authorize 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=refresh_token&client_id=s6BhdRkqt3&client_secret=8eSEIpnqmM type=refresh_token&client_id=s6BhdRkqt3&client_secret=8eSEIpnqmM
&refresh_token=n4E9O119d&secret_type=hmac-sha256 &refresh_token=n4E9O119d&secret_type=hmac-sha256
The authorization server MUST verify the client credential, the The authorization server MUST verify the client credential, 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 a new access token and includes the authorization server issues a new access token and includes the
skipping to change at page 37, line 41 skipping to change at page 37, line 41
If the request fails verification, the authorization server returns If the request fails verification, the authorization server returns
an error message in the HTTP response body using the an error message in the HTTP response body using the
"application/x-www-form-urlencoded" content type as defined by "application/x-www-form-urlencoded" content type as defined by
[W3C.REC-html40-19980424] with a 400 status code (Bad Request). [W3C.REC-html40-19980424] with a 400 status code (Bad Request).
The response contains the following parameter: The response contains the following parameter:
error error
OPTIONAL. The parameter value MUST be set to either OPTIONAL. The parameter value MUST be set to either
"incorrect_credentials", "authorization_expired", or "incorrect_credentials", "authorization_expired", or
"unsupported_secret_type" (case sensitive). "unsupported_secret_type".
For example: For example:
HTTP/1.1 400 Bad Request HTTP/1.1 400 Bad Request
Content-Type: application/x-www-form-urlencoded Content-Type: application/x-www-form-urlencoded
error=incorrect_credentials error=incorrect_credentials
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 methods used by the resource server to the resource server. The methods used by the resource server to
validate the access token are beyond the scope of this specification, validate the access token are beyond the scope of this specification,
but generally involve an interaction or coordination between the but generally involve an interaction or coordination between the
resource server and authorization server. resource server and authorization server.
The method in which a client uses an access token depends on the The method in which a client uses an access token depends on the
security properties of the access tokens. By default, access tokens security properties of the access tokens. By default, access tokens
are issued without a matching secret. Clients MAY request an access are issued without a matching secret. Clients MAY request an access
token with a matchin secret by specifying the desired secret type token with a matching secret by specifying the desired secret type
using the "secret_type" token request parameter. using the "secret_type" token request parameter.
When an access token does not include a matching secret, the access When an access token does not include a matching secret, the access
token acts as a bearer token, where the token string is a shared token acts as a bearer token, where the token string is a shared
symmetric secret. This requires treating the access token with the symmetric secret. This requires treating the access token with the
same care as other secrets (e.g. user passwords). Access tokens same care as other secrets (e.g. user passwords). Access tokens
SHOULD NOT be sent in the clear over an insecure channel. 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 bearer tokens in the clear
without a secure channel, authorization servers must 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. Clients SHOULD request and utilize from a compromised access token. Clients SHOULD request and utilize
an access token with a matching secret when making protected resource an access token with a matching secret when making protected resource
requests over an insecure channel (e.g. an HTTP request without using requests over an insecure channel (e.g. an HTTP request without using
SSL/TLS). TLS/SSL).
When an access token includes a matching secret, the secret is not When an access token includes a matching secret, the secret is not
included directly in the request but is used instead to generate a included directly in the request but is used instead to generate a
cryptographic signature of the request. The signature can only be cryptographic signature of the request. The signature can only be
generated and verified by entities with access to the secret. generated and verified by entities with access to the secret.
Clients SHOULD NOT make authenticated requests with an access token Clients SHOULD NOT make authenticated requests with an access token
to unfamiliar resource servers, especially when using bearer tokens, to unfamiliar resource servers, especially when using bearer tokens,
regardless of the presence of a secure channel. regardless of the presence of a secure channel.
skipping to change at page 41, line 8 skipping to change at page 41, line 8
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 The resource server MUST validate the access token and ensure it has
not expired and its includes the requested resource. If the resource not expired and its scope includes the requested resource. If the
expired or is not valid, the resource server MUST reply with an HTTP resource expired or is not valid, the resource server MUST reply with
401 status code (Unauthorized) and include the HTTP an HTTP 401 status code (Unauthorized) and include the HTTP
"WWW-Authenticate" response header as described in Section 6.1. "WWW-Authenticate" response header as described in Section 6.1.
5.2.2. Form-Encoded Body Parameter 5.2.2. 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.
skipping to change at page 41, line 45 skipping to change at page 41, line 45
For example, the client makes the following HTTPS request: For example, the client makes the following HTTPS request:
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 The resource server MUST validate the access token and ensure it has
not expired and its includes the requested resource. If the resource not expired and its scope includes the requested resource. If the
expired or is not valid, the resource server MUST reply with an HTTP resource expired or is not valid, the resource server MUST reply with
401 status code (Unauthorized) and include the HTTP an HTTP 401 status code (Unauthorized) and include the HTTP
"WWW-Authenticate" response header as described in Section 6.1. "WWW-Authenticate" response header as described in Section 6.1.
5.3. Cryptographic Tokens Requests 5.3. Cryptographic Tokens Requests
Clients make authenticated protected resource requests using an Clients make authenticated protected resource requests using an
access token with a matching secret by calculating a set of values access token with a matching secret by calculating a set of values
and including them in the request using the "Authorization" header and including them in the request using the "Authorization" header
field. The way clients calculate these values depends on the access field. The way clients calculate these values depends on the access
token secret type as issued by the authorization server. token secret type as issued by the authorization server.
This specification defines the "hmac-sha256" algorithm, and This specification defines the "hmac-sha256" algorithm, and
establishes a registry for providing additional algorithms. Clients establishes a registry for providing additional algorithms. Clients
obtain an access token with a matchin "hmac-sha256" secret by using obtain an access token with a matching "hmac-sha256" secret by using
the "token_type" parameter when requesting an access token. the "token_type" parameter when requesting an access token.
5.3.1. The 'hmac-sha256' Algorithm 5.3.1. The 'hmac-sha256' Algorithm
The "hmac-sha256" algorithm uses the HMAC method as defined in The "hmac-sha256" algorithm uses the HMAC method as defined in
[RFC2104] together with the SHA-256 hash function defined in [NIST [RFC2104] together with the SHA-256 hash function defined in [NIST
FIPS-180-3] to apply the access token secret to the request and FIPS-180-3] to apply the access token secret to the request and
generate a signature value that is included in the request instead of generate a signature value that is included in the request instead of
transmitting the secret in the clear. transmitting the secret in the clear.
skipping to change at page 44, line 9 skipping to change at page 44, line 9
concatenation of several of the HTTP request elements into a single concatenation of several of the HTTP request elements into a single
string. The string is used as an input to the selected cryptographic string. The string is used as an input to the selected cryptographic
method and includes the HTTP request method (e.g. "GET", "POST", method and includes the HTTP request method (e.g. "GET", "POST",
etc.), the authority as declared by the HTTP "Host" request header, etc.), the authority as declared by the HTTP "Host" request header,
and the request resource URI. and the request resource URI.
The normalized request string does not cover the entire HTTP request. The normalized request string does not cover the entire HTTP request.
Most notably, it does not include the entity-body or most HTTP Most notably, it does not include the entity-body or most HTTP
entity-headers. It is important to note that the resource server entity-headers. It is important to note that the resource server
cannot verify the authenticity of the excluded request elements cannot verify the authenticity of the excluded request elements
without using additional protections such as SSL/TLS. without using additional protections such as TLS/SSL.
The normalized request string is constructed by concatenating The normalized request string is constructed by concatenating
together, in order, the following HTTP request elements, separated by together, in order, the following HTTP request elements, separated by
the "," character (ASCII code 44): the "," character (ASCII code 44):
1. The request timestamp as described in Section 5.3.1.1. 1. The request timestamp as described in Section 5.3.1.1.
2. The request nonce as described in Section 5.3.1.1. 2. The request nonce as described in Section 5.3.1.1.
3. The cryptographic algorithm used. 3. The cryptographic algorithm used.
skipping to change at page 47, line 9 skipping to change at page 47, line 9
[[ Add OAuth 1.0a authors + WG contributors ]] [[ Add OAuth 1.0a authors + WG contributors ]]
Appendix A. Differences from OAuth 1.0a Appendix A. Differences from OAuth 1.0a
[[ Todo ]] [[ Todo ]]
Appendix B. Document History Appendix B. Document History
[[ to be removed by RFC editor before publication as an RFC ]] [[ to be removed by RFC editor before publication as an RFC ]]
-01
o Editorial changes based on feedback from Brian Eaton, Bill Keenan,
and Chuck Mortimore.
o Changed devide flow "type" parameter values and switch to use only
the token endpoint.
-00 -00
o Initial draft based on a combination of WRAP and OAuth 1.0a. o Initial draft based on a combination of WRAP and OAuth 1.0a.
10. References 10. References
10.1. Normative References 10.1. Normative References
[I-D.ietf-httpbis-p1-messaging] [I-D.ietf-httpbis-p1-messaging]
Fielding, R., Gettys, J., Mogul, J., Nielsen, H., Fielding, R., Gettys, J., Mogul, J., Nielsen, H.,
 End of changes. 145 change blocks. 
235 lines changed or deleted 248 lines changed or added

This html diff was produced by rfcdiff 1.38. The latest version is available from http://tools.ietf.org/tools/rfcdiff/