| OAuth Working Group | M. Jones |
| Internet-Draft | A. Nadalin |
| Intended status: Standards Track | Microsoft |
| Expires: June 16, 2016 | B. Campbell |
| J. Bradley | |
| Ping Identity | |
| C. Mortimore | |
| Salesforce | |
| December 14, 2015 |
OAuth 2.0 Token Exchange: An STS for the REST of Us
draft-ietf-oauth-token-exchange-03
This specification defines a protocol for a lightweight HTTP- and JSON- based Security Token Service (STS) by defining how to request and obtain security tokens from OAuth 2.0 authorization servers, including security tokens employing impersonation and delegation.
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A security token is a set of information that facilitates the sharing of identity and security information in heterogeneous environments or across security domains. Examples of security tokens include JSON Web Tokens (JWTs) [JWT] and SAML Assertions [OASIS.saml-core-2.0-os]. Security tokens are typically signed to achieve integrity and sometimes also encrypted to achieve confidentiality. Security tokens are also sometimes described as Assertions, such as in [RFC7521].
A Security Token Service (STS) is a service capable of validating and issuing security tokens, which enables clients to obtain appropriate access credentials for resources in heterogeneous environments or across security domains. Web Service clients have used WS-Trust [WS-Trust] as the protocol to interact with an STS for token exchange, however WS-Trust is a fairly heavyweight protocol, which uses XML, SOAP, etc. Whereas, the trend in modern Web development has been towards lightweight services utilizing RESTful patterns and JSON. The OAuth 2.0 Authorization Framework [RFC6749] and OAuth 2.0 Bearer Tokens [RFC6750] have emerged as popular standards for authorizing and securing access to HTTP and RESTful resources but do not provide everything necessary to facilitate token exchange interactions.
This specification defines a lightweight protocol extending OAuth 2.0 that enables clients to request and obtain security tokens from authorization servers acting in the role of an STS. Similar to OAuth 2.0, this specification focuses on client developer simplicity and requires only an HTTP client and JSON parser, which are nearly universally available in modern development environments. The STS protocol defined in this specification is not itself RESTful (an STS doesn't lend itself particularly well to a REST approach) but does utilize communication patterns and data formats that should be familiar to developers accustomed to working with RESTful systems.
A new grant type for a token exchange request and the associated specific parameters for such a request to the token endpoint are defined by this specification. A token exchange response is a normal OAuth 2.0 response from the token endpoint with a few additional parameters defined herein to provide information to the client.
The entity that makes the request to exchange tokens is considered the client in the context of the token exchange interaction. However, that does not restrict usage of this profile to traditional OAuth clients. An OAuth resource server, for example, might assume the role of the client during token exchange in order to trade an access token, which it received in a protected resource request, for a new token that is appropriate to include in a call to a backend service. The new token might be an access token that is more narrowly scoped for the downstream service or it could be an entirely different kind of token.
The scope of this specification is limited to the definition of a basic request and response protocol for an STS-style token exchange utilizing OAuth 2.0. Although a few new JWT claims are defined that enable delegation semantics to be expressed, the specific syntax, semantics and security characteristics of the tokens themselves (both those presented to the AS and those obtained by the client) are explicitly out of scope and no requirements are placed on the trust model in which an implementation might be deployed. Additional profiles may provide more detailed requirements around the specific nature of the parties and trust involved, such as whether signing and/or encryption of tokens is required; however, such details will often be policy decisions made with respect to the specific needs of individual deployments and will be configured or implemented accordingly.
The security tokens obtained could be used in a number of contexts, the specifics of which are also beyond the scope of this specification.
When principal A impersonates principal B, A is given all the rights that B has within some defined rights context and is indistinguishable from B in that context. Thus, when principal A impersonates principal B, then in so far as any entity receiving such a token is concerned, they are actually dealing with B. It is true that some members of the identity system might have awareness that impersonation is going on, but it is not a requirement. For all intents and purposes, when A is impersonating B, A is B.
Delegation semantics are different than impersonation semantics, though the two are closely related. With delegation semantics, principal A still has its own identity separate from B and it is explicitly understood that while B may have delegated some of its rights to A, any actions taken are being taken by A representing B. In a sense, A is an agent for B.
Delegation and impersonation are not inclusive of all situations. When a principal is acting directly on its own behalf, for example, neither delegation nor impersonation are in play. They are, however, the more common semantics operating for token exchange and, as such, are given more direct treatment in this specification.
Delegation semantics are typically expressed in a token by including information about both the primary subject of the token as well as the actor to whom that subject has delegated some of its rights. Such a token is sometimes referred to as a composite token because it is composed of information about multiple subjects. A client can indicate the desire for a composite token by including a want_composite parameter in the request with the value true. Typically, in the request, the subject_token represents the identity of the party on behalf of whom the token is being requested while the actor_token represents the identity of the party to whom the access rights of the issued token are being delegated. A composite token issued by the authorization server will contain information about both parties.
The specifics of representing a composite token and even whether or not such a token will be issued depend on the details of the implementation and the kind of token. The representations of composite tokens that are not JWTs are beyond the scope of this specification. The Section 4.1 request parameter, however, does provide a means for providing information about the desired actor though the representation of a chain of delegation using the JWT act claim.
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119 [RFC2119].
This specification uses the terms "access token type", "authorization server", "client", "client identifier", "resource server", "token endpoint", "token request", and "token response" defined by OAuth 2.0 [RFC6749], and the terms "Claim" and "JWT Claims Set" defined by JSON Web Token (JWT) [JWT].
A client requests a security token by making a token request to the authorization server's token endpoint using the extension grant type mechanism defined in Section 4.5 of OAuth 2.0 [RFC6749].
Client authentication to the authorization server is done using the normal mechanisms provided by OAuth 2.0. Section 2.3.1 of The OAuth 2.0 Authorization Framework [RFC6749] defines password-based authentication of the client, however, client authentication is extensible and other mechanisms are possible. For example, [RFC7523] defines client authentication using JSON Web Tokens (JWTs) [JWT]. The supported methods of client authentication and whether or not to allow unauthenticated or unidentified clients are deployment decisions that are at the discretion of the authorization server.
The client makes a token exchange request to the token endpoint with an extension grant type by including the following parameters using the application/x-www-form-urlencoded format with a character encoding of UTF-8 in the HTTP request entity-body:
The authorization server responds to a token exchange request with a normal OAuth 2.0 response from the token endpoint, as specified in Section 5 of [RFC6749]. Additional details and explanation are provided in the following subsections.
If the request is valid and meets all policy and other criteria of the authorization server, a successful token response is constructed by adding the following parameters to the entity-body of the HTTP response using the "application/json" media type, as specified by [RFC7159], and an HTTP 200 status code. The parameters are serialized into a JavaScript Object Notation (JSON) structure by adding each parameter at the top level. Parameter names and string values are included as JSON strings. Numerical values are included as JSON numbers. The order of parameters does not matter and can vary.
If either the subject_token or actor_token are invalid for any reason, or are unacceptable based on policy, the authorization server MUST construct an error response, as specified in Section 5.2 of [RFC6749]. The value of the error parameter MUST be the invalid_request error code. The authorization server MAY include additional information regarding the reasons for the error using the error_description and/or error_uri parameters. Other error codes may also be used, as appropriate.
The following example demonstrates a hypothetical token exchange in which an OAuth resource server assumes the role of the client during token exchange in order to trade an access token that it received in a request for a token that it will use to call to a backend service (extra line breaks and indentation in the examples are for display purposes only).
The resource server receives the following request containing an OAuth access token in the Authorization request header, as specified in Section 2.1 of [RFC6750].
GET /resource HTTP/1.1 Host: frontend.example.com Authorization: Bearer accVkjcJyb4BWCxGsndESCJQbdFMogUC5PbRDqceLTC
Figure 1: Protected Resource Request
The resource server assumes the role of the client for the token exchange and the access token from the request above is sent to the authorization server using a request as specified in Section 2.1. The value of the subject_token parameter carries the access token and the value of the subject_token_type parameter indicates that it is an OAuth 2.0 access token. The resource server, acting as the client, uses its identifier and secret to authenticate to the authorization server using the HTTP Basic authentication scheme. The resource parameter indicates the location of the backend service, https://backend.example.com/api, where the issued token will be used.
POST /as/token.oauth2 HTTP/1.1 Host: as.example.com Authorization: Basic cnMwODpsb25nLXNlY3VyZS1yYW5kb20tc2VjcmV0 Content-Type: application/x-www-form-urlencoded grant_type=urn%3Aietf%3Aparams%3Aoauth%3Agrant-type%3Atoken-exchange &resource=https%3A%2F%2Fbackend.example.com%2Fapi%20 &subject_token=accVkjcJyb4BWCxGsndESCJQbdFMogUC5PbRDqceLTC &subject_token_type= urn%3Aietf%3Aparams%3Aoauth%3Atoken-type%3Aaccess_token
Figure 2: Token Exchange Request
The authorization server validates the client credentials and the subject_token presented in the token exchange request. From the resource parameter, the authorization server is able to determine the appropriate policy to apply to the request and issues a token suitable for use at https://backend.example.com. The access_token parameter of the response contains the new token, which is itself a bearer OAuth access token that is valid for one minute. The token happens to be a JWT; however, its structure and format are opaque to the client so the issued_token_type indicates only that it is an access token.
HTTP/1.1 200 OK
Content-Type: application/json
Cache-Control: no-cache, no-store
{
"access_token":"eyJhbGciOiJFUzI1NiIsImtpZCI6IjllciJ9.eyJhdWQiOiJo
dHRwczovL2JhY2tlbmQuZXhhbXBsZS5jb20iLCJpc3MiOiJodHRwczovL2FzLmV
4YW1wbGUuY29tIiwiZXhwIjoxNDQxOTE3NTkzLCJpYXQiOjE0NDE5MTc1MzMsIm
F6cCI6InJzMDgiLCJzdWIiOiJiY0BleGFtcGxlLmNvbSIsInNjcCI6WyJhcGkiX
X0.vHJKtJ-zFIN75Tk7qGlmQsWPlvnChb2uSaGwPLvlWl64ts7-vvfwYDaVoXIQ
e_HkTVdljIzavVlPT60_b_9pDQ",
"issued_token_type":
"urn:ietf:params:oauth:token-type:access_token",
"token_type":"Bearer",
"expires_in":60
}
Figure 3: Token Exchange Response
The resource server can then use the newly acquired access token in making a request to the backend server.
GET /api HTTP/1.1
Host: backend.example.com
Authorization: Bearer eyJhbGciOiJFUzI1NiIsImtpZCI6IjllciJ9.eyJhdWQ
iOiJodHRwczovL2JhY2tlbmQuZXhhbXBsZS5jb20iLCJpc3MiOiJodHRwczovL2
FzLmV4YW1wbGUuY29tIiwiZXhwIjoxNDQxOTE3NTkzLCJpYXQiOjE0NDE5MTc1M
zMsImF6cCI6InJzMDgiLCJzdWIiOiJiY0BleGFtcGxlLmNvbSIsInNjcCI6WyJh
cGkiXX0.vHJKtJ-zFIN75Tk7qGlmQsWPlvnChb2uSaGwPLvlWl64ts7-vvfwYDa
VoXIQe_HkTVdljIzavVlPT60_b_9pDQ
Figure 4: Backend Protected Resource Request
Additional examples can be found in Appendix A.
Several parameters in this specification utilize an identifier as the value to describe the type of token in question. Specifically, they are the requested_token_type, subject_token_type, actor_token_type parameters of the request and the issued_token_type member of the response. Token type identifiers are URIs.
This specification defines the token type identifiers urn:ietf:params:oauth:token-type:access_token and urn:ietf:params:oauth:token-type:refresh_token to indicate that the token is an OAuth 2.0 access token or refresh token, respectively. The value urn:ietf:params:oauth:token-type:jwt defined in Section 9 of [JWT] indicates that the token is a JWT. Other URIs to indicate other token types MAY be used.
It is useful to have defined mechanisms to express delegation within a token as well as to express authorization to delegate or impersonate. Although the token exchange protocol described herein can be used with any type of token, this section defines claims to express such semantics specifically for JWTs. Similar definitions for other types of tokens are possible but beyond the scope of this specification.
The act (actor) claim provides a means within a JWT to express that delegation has occurred and identify the acting party to whom authority has been delegated. The act claim value is a JSON object and members in the JSON object are claims that identify the actor. The claims that make up the act claim identify and possibly provide additional information about the actor. For example, the combination of the two claims iss and sub might be necessary to uniquely identify an actor.
However, claims within the act claim pertain only to the identity of the actor and are not relevant to the validity of the containing JWT in the same manner as the top-level claims. Consequently, claims such as exp, nbf, and aud are not meaningful when used within an act claim, and therefore should not be used.
The following example illustrates the act (actor) claim within a JWT Claims Set. The claims of the token itself are about user@example.com while the act claim indicates that admin@example.com is the current actor.
{
"aud":"https://consumer.example.com",
"iss":"https://issuer.example.com",
"exp":1443904177,
"nbf":1443904077,
"sub":"user@example.com",
"act":
{
"sub":"admin@example.com"
}
}
Figure 5: Actor Claim
A chain of delegation can be expressed by nesting one act claim within another. The outermost act claim represents the current actor while nested act claims represent prior actors. The least recent actor is the most deeply nested.
The following example illustrates nested act (actor) claims within a JWT Claims Set. The claims of the token itself are about user@example.com while the act claim indicates that the system consumer.example.com-web-application is the current actor and admin@example.com was a prior actor. Such a token might come about as the result of the web application receiving a token like the one in the previous example and exchanging it for a new token that lists it as the current actor and that can be used at https://backend.example.com.
{
"aud":"https://backend.example.com",
"iss":"https://issuer.example.com",
"exp":1443904100,
"nbf":1443904000,
"sub":"user@example.com",
"act":
{
"sub":"consumer.example.com-web-application",
"iss":"https://issuer.example.net",
"act":
{
"sub":"admin@example.com"
}
}
}
Figure 6: Nested Actor Claim
The scp claim is an array of strings, each of which represents an OAuth scope granted for the issued security token. Each array entry of the claim value is a scope-token, as defined in Section 3.3 of OAuth 2.0 [RFC6749].
The following example illustrates the scp claim within a JWT Claims Set with four scope-tokens.
{
"aud":"https://consumer.example.com",
"iss":"https://issuer.example.com",
"exp":1443904177,
"nbf":1443904077,
"sub":"dgaf4mvfs75Fci_FL3heQA",
"scp":["email","address","profile","phone"]
}
Figure 7: Scopes Claim
The may_act claim makes a statement that one party is authorized to become the actor and act on behalf of another party. The claim value is a JSON object and members in the JSON object are claims that identify the party that is asserted as being eligible to act for the party identified by the JWT containing the claim. The claims that make up the may_act claim identify and possibly provide additional information about the authorized actor. For example, the combination of the two claims iss and sub are sometimes necessary to uniquely identify an authorized actor, while the email claim might be used to provide additional useful information about that party.
However, claims within the may_act claim pertain only to the identity of that party and are not relevant to the validity of the containing JWT in the same manner as top level claims. Consequently, claims such as exp, nbf, and aud are not meaningful when used within a may_act claim, and therefore should not be used.
The following example illustrates the may_act claim within a JWT Claims Set. The claims of the token itself are about user@example.com while the may_act claim indicates that admin@example.com is authorized to act on behalf of user@example.com.
{
"aud":"https://consumer.example.com",
"iss":"https://issuer.example.com",
"exp":1443904177,
"nbf":1443904077,
"sub":"user@example.com",
"may_act":
{
"sub":"admin@example.com"
}
}
Figure 8: May Act For Claim
This specification registers the following values in the IANA "OAuth URI" registry [IANA.OAuth.Parameters] established by [RFC6755].
This specification registers the following values in the IANA "OAuth Parameters" registry [IANA.OAuth.Parameters] established by [RFC6749].
This specification registers the following access token type in the IANA "OAuth Access Token Types" registry [IANA.OAuth.Parameters] established by [RFC6749].
This specification registers the following Claims in the IANA "JSON Web Token Claims" registry [IANA.JWT.Claims] established by [JWT].
All of the normal security issues that are discussed in [JWT], especially in relationship to comparing URIs and dealing with unrecognized values, also apply here.
In addition, both delegation and impersonation introduce unique security issues. Any time one principal is delegated the rights of another principal, the potential for abuse is a concern. The use of the scp claim is suggested to mitigate potential for such abuse, as it restricts the contexts in which the delegated rights can be exercised.
| [IANA.JWT.Claims] | IANA, "JSON Web Token Claims" |
| [IANA.OAuth.Parameters] | IANA, "OAuth Parameters" |
| [JWT] | Jones, M., Bradley, J. and N. Sakimura, "JSON Web Token (JWT)", RFC 7519, DOI 10.17487/RFC7519, May 2015. |
| [RFC2119] | Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997. |
| [RFC3986] | Berners-Lee, T., Fielding, R. and L. Masinter, "Uniform Resource Identifier (URI): Generic Syntax", STD 66, RFC 3986, DOI 10.17487/RFC3986, January 2005. |
| [RFC6749] | Hardt, D., "The OAuth 2.0 Authorization Framework", RFC 6749, DOI 10.17487/RFC6749, October 2012. |
| [RFC7159] | Bray, T., "The JavaScript Object Notation (JSON) Data Interchange Format", RFC 7159, DOI 10.17487/RFC7159, March 2014. |
Two example token exchanges are provided in the following sections illustrating impersonation and delegation, respectively (with extra line breaks and indentation for display purposes only).
In the following token exchange request, an anonymous client is requesting a token with impersonation semantics. The client tells the authorization server that it needs a token for use at the target service with the logical name urn:example:cooperation-context.
POST /as/token.oauth2 HTTP/1.1 Host: as.example.com Content-Type: application/x-www-form-urlencoded grant_type=urn%3Aietf%3Aparams%3Aoauth%3Agrant-type%3Atoken-exchange &audience=urn%3Aexample%3Acooperation-context &subject_token=eyJhbGciOiJFUzI1NiIsImtpZCI6IjE2In0.eyJhdWQiOiJodHRwc zovL2FzLmV4YW1wbGUuY29tIiwiaXNzIjoiaHR0cHM6Ly9jbGllbnQuZXhhbXBsZS5 uZXQiLCJleHAiOjE0NDE5MTA2MDAsIm5iZiI6MTQ0MTkwOTAwMCwic3ViIjoiYmNAZ XhhbXBsZS5uZXQiLCJzY3AiOlsib3JkZXJzIiwicHJvZmlsZSIsImhpc3RvcnkiXX0 .F1EZzN9j3LwyrLkDD8pjR7fzHqdYl1ly-jEILfmgKY_0hNuT3_fmUChu9oQdBNjHj wu58iLSmagZl-5_9-ilzw &subject_token_type=urn%3Aietf%3Aparams%3Aoauth%3Atoken-type%3Ajwt
Figure 9: Token Exchange Request
The subject_token in the prior request is a JWT and the decoded JWT Claims Set is shown here. The JWT is intended for consumption by the authorization server within a specific time window. The subject of the JWT (bc@example.net) is the party on behalf of whom the new token is being requested.
{
"aud":"https://as.example.com",
"iss":"https://client.example.net",
"exp":1441910600,
"nbf":1441909000,
"sub":"bc@example.net",
"scp":["orders","profile","history"]
}
Figure 10: Subject Token Claims
The access_token parameter of the token exchange response shown below contains the new token that the client requested. The other parameters of the response indicate that the token is a JWT that expires in an hour and that the access token type is not applicable since the issued token is not an access token.
HTTP/1.1 200 OK
Content-Type: application/json
Cache-Control: no-cache, no-store
{
"access_token":"eyJhbGciOiJFUzI1NiIsImtpZCI6IjcyIn0.eyJhdWQiOiJ1cm4
6ZXhhbXBsZTpjb29wZXJhdGlvbi1jb250ZXh0IiwiaXNzIjoiaHR0cHM6Ly9hcy5l
eGFtcGxlLmNvbSIsImV4cCI6MTQ0MTkxMzYxMCwic3ViIjoiYmNAZXhhbXBsZS5uZ
XQiLCJzY3AiOlsib3JkZXJzIiwiaGlzdG9yeSIsInByb2ZpbGUiXX0.YQHuLmI1YD
TugbfEvgGY2gaGBmMyj9BepZSECCBE9j9ogqZv2qx6VQQPrbT1k7vBYGLNMOkkpmm
JkxZDS0YV7g",
"issued_token_type":"urn:ietf:params:oauth:token-type:jwt",
"token_type":"N_A",
"expires_in":3600
}
Figure 11: Token Exchange Response
The decoded JWT Claims Set of the issued token is shown below. The new JWT is issued by the authorization server and intended for consumption by a system entity known by the logical name urn:example:cooperation-context any time before its expiration. The subject (sub) of the JWT is the same as the subject the token used to make the request, which effectively enables the client to impersonate that subject at the system entity known by the logical name of urn:example:cooperation-context by using the token.
{
"aud":"urn:example:cooperation-context",
"iss":"https://as.example.com",
"exp":1441913610,
"sub":"bc@example.net",
"scp":["orders","history","profile"]
}
Figure 12: Issued Token Claims
In the following token exchange request, an anonymous client is requesting a token with delegation semantics, which is indicated by the inclusion of the want_composite parameter. The client tells the authorization server that it needs a token for use at the target service with the logical name urn:example:cooperation-context.
POST /as/token.oauth2 HTTP/1.1 Host: as.example.com Content-Type: application/x-www-form-urlencoded grant_type=urn%3Aietf%3Aparams%3Aoauth%3Agrant-type%3Atoken-exchange &audience=urn%3Aexample%3Acooperation-context &want_composite=true &subject_token=eyJhbGciOiJFUzI1NiIsImtpZCI6IjE2In0.eyJhdWQiOiJodHRwc zovL2FzLmV4YW1wbGUuY29tIiwiaXNzIjoiaHR0cHM6Ly9jbGllbnQuZXhhbXBsZS5 uZXQiLCJleHAiOjE0NDE5MTAwNjAsInNjcCI6WyJzdGF0dXMiLCJmZWVkIl0sInN1Y iI6InVzZXJAZXhhbXBsZS5uZXQiLCJtYXlfYWN0Ijp7InN1YiI6ImFkbWluQGV4YW1 wbGUubmV0In19.cklRpQMYzs9AYoJ3DMht1OnMhAF_0YeQgV35rp7J7ErkvnPm1gr_ OeQD1wTbnbburbyC7nwKdK5Jrn31aQPxUg &subject_token_type=urn%3Aietf%3Aparams%3Aoauth%3Atoken-type%3Ajwt &actor_token=eyJhbGciOiJFUzI1NiIsImtpZCI6IjE2In0.eyJhdWQiOiJodHRwczo vL2FzLmV4YW1wbGUuY29tIiwiaXNzIjoiaHR0cHM6Ly9jbGllbnQuZXhhbXBsZS5uZ XQiLCJleHAiOjE0NDE5MTAwNjAsInN1YiI6ImFkbWluQGV4YW1wbGUubmV0In0.X15 8zUsO55Fo0humOUCUCy582BQRAWbMsIKbxT1mJRrQrk2cpU6r6CWeI4ukQoQRe6RTr Esk4wX2lMf8sELxaA &actor_token_type=urn%3Aietf%3Aparams%3Aoauth%3Atoken-type%3Ajwt
Figure 13: Token Exchange Request
The subject_token in the prior request is a JWT and the decoded JWT Claims Set is shown here. The JWT is intended for consumption by the authorization server before a specific expiration time. The subject of the JWT (user@example.net) is the party on behalf of whom the new token is being requested.
{
"aud":"https://as.example.com",
"iss":"https://client.example.net",
"exp":1441910060,
"scp":["status","feed"],
"sub":"user@example.net",
"may_act":
{
"sub":"admin@example.net"
}
}
Figure 14: Subject Token Claims
The actor_token in the prior request is a JWT and the decoded JWT Claims Set is shown here. This JWT is also intended for consumption by the authorization server before a specific expiration time. The subject of the JWT (admin@example.net) is the actor that will wield the security token being requested.
{
"aud":"https://as.example.com",
"iss":"https://client.example.net",
"exp":1441910060,
"sub":"admin@example.net"
}
Figure 15: Actor Token Claims
The access_token parameter of the token exchange response shown below contains the new token that the client requested. The other parameters of the response indicate that the token is a JWT that expires in an hour and that the access token type is not applicable since the issued token is not an access token.
HTTP/1.1 200 OK
Content-Type: application/json
Cache-Control: no-cache, no-store
{
"access_token":"eyJhbGciOiJFUzI1NiIsImtpZCI6IjcyIn0.eyJhdWQiOiJ1cm4
6ZXhhbXBsZTpjb29wZXJhdGlvbi1jb250ZXh0IiwiaXNzIjoiaHR0cHM6Ly9hcy5l
eGFtcGxlLmNvbSIsImV4cCI6MTQ0MTkxMzYxMCwic2NwIjpbInN0YXR1cyIsImZlZ
WQiXSwic3ViIjoidXNlckBleGFtcGxlLm5ldCIsImFjdCI6eyJzdWIiOiJhZG1pbk
BleGFtcGxlLm5ldCJ9fQ._qjM7Ij_HcrC78omT4jiZTFJOuzsAj1wPo31ymQS-Suq
r64S1jCp6pfQR-in_OOAosAGamEg4jyPsht6kMAiYA",
"issued_token_type":"urn:ietf:params:oauth:token-type:jwt",
"token_type":"N_A",
"expires_in":3600
}
Figure 16: Token Exchange Response
The decoded JWT Claims Set of the issued token is shown below. The new JWT is issued by the authorization server and intended for consumption by a system entity known by the logical name urn:example:cooperation-context any time before its expiration. The subject (sub) of the JWT is the same as the subject of the subject_token used to make the request. The actor (act) of the JWT is the same as the subject of the actor_token used to make the request. This indicates delegation and identifies admin@example.net as the current actor to whom authority has been delegated to act on behalf of user@example.net.
{
"aud":"urn:example:cooperation-context",
"iss":"https://as.example.com",
"exp":1441913610,
"scp":["status","feed"],
"sub":"user@example.net",
"act":
{
"sub":"admin@example.net"
}
}
Figure 17: Issued Token Claims
This specification was developed within the OAuth Working Group, which includes dozens of active and dedicated participants. It was produced under the chairmanship of Hannes Tschofenig and Derek Atkins with Kathleen Moriarty and Stephen Farrell serving as Security Area Directors. The following individuals contributed ideas, feedback, and wording to this specification:
Caleb Baker, William Denniss, Phil Hunt, Jason Keglovitz, Matt Miller, Matthew Perry, Justin Richer, Scott Tomilson, and Hannes Tschofenig.
The following decisions need to be made and updates to this spec performed:
[[ to be removed by the RFC Editor before publication as an RFC ]]
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