Internet Engineering Task Force (IETF)               T. Lodderstedt, Ed.
Request for Comments: 7009                           Deutsche Telekom AG
Category: Standards Track                                      S. Dronia
ISSN: 2070-1721
                                                            M. Scurtescu
                                                             August 2013

OAuth 2.0 Token Revocation

OAuth 2.0トークンの取り消し



This document proposes an additional endpoint for OAuth authorization servers, which allows clients to notify the authorization server that a previously obtained refresh or access token is no longer needed. This allows the authorization server to clean up security credentials. A revocation request will invalidate the actual token and, if applicable, other tokens based on the same authorization grant.


Status of This Memo


This is an Internet Standards Track document.

これはInternet Standards Trackドキュメントです。

This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 5741.

このドキュメントは、IETF(Internet Engineering Task Force)の製品です。これは、IETFコミュニティのコンセンサスを表しています。公開レビューを受け、インターネットエンジニアリングステアリンググループ(IESG)による公開が承認されました。インターネット標準の詳細については、RFC 5741のセクション2をご覧ください。

Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at


Copyright Notice


Copyright (c) 2013 IETF Trust and the persons identified as the document authors. All rights reserved.

Copyright(c)2013 IETF Trustおよびドキュメントの作成者として識別された人物。全著作権所有。

This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents ( in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License.

この文書は、BCP 78およびこの文書の発行日に有効なIETF文書に関するIETFトラストの法的規定(の対象となります。これらのドキュメントは、このドキュメントに関するあなたの権利と制限を説明しているため、注意深く確認してください。このドキュメントから抽出されたコードコンポーネントには、Trust Legal Provisionsのセクション4.eに記載されているSimplified BSD Licenseのテキストが含まれている必要があり、Simplified BSD Licenseに記載されているように保証なしで提供されます。

Table of Contents


   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
     1.1.  Requirements Language . . . . . . . . . . . . . . . . . .   3
   2.  Token Revocation  . . . . . . . . . . . . . . . . . . . . . .   3
     2.1.  Revocation Request  . . . . . . . . . . . . . . . . . . .   4
     2.2.  Revocation Response . . . . . . . . . . . . . . . . . . .   5
       2.2.1.  Error Response  . . . . . . . . . . . . . . . . . . .   6
     2.3.  Cross-Origin Support  . . . . . . . . . . . . . . . . . .   6
   3.  Implementation Note . . . . . . . . . . . . . . . . . . . . .   7
   4.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   8
     4.1.  OAuth Extensions Error Registration . . . . . . . . . . .   8
       4.1.1.  The "unsupported_token_type" Error Value  . . . . . .   8
       4.1.2.  OAuth Token Type Hints Registry . . . . . . . . . . .   8  Registration Template . . . . . . . . . . . . . .   9  Initial Registry Contents . . . . . . . . . . . .   9
   5.  Security Considerations . . . . . . . . . . . . . . . . . . .   9
   6.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  10
   7.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  10
     7.1.  Normative References  . . . . . . . . . . . . . . . . . .  10
     7.2.  Informative References  . . . . . . . . . . . . . . . . .  11
1. Introduction
1. はじめに

The OAuth 2.0 core specification [RFC6749] defines several ways for a client to obtain refresh and access tokens. This specification supplements the core specification with a mechanism to revoke both types of tokens. A token is a string representing an authorization grant issued by the resource owner to the client. A revocation request will invalidate the actual token and, if applicable, other tokens based on the same authorization grant and the authorization grant itself.

OAuth 2.0コア仕様[RFC6749]は、クライアントがリフレッシュトークンを取得してアクセスするためのいくつかの方法を定義しています。この仕様は、両方のタイプのトークンを取り消すメカニズムでコア仕様を補足します。トークンは、リソース所有者がクライアントに発行する承認付与を表す文字列です。失効リクエストは、実際のトークンと、該当する場合は、同じ許可付与と許可付与自体に基づく他のトークンを無効にします。

From an end-user's perspective, OAuth is often used to log into a certain site or application. This revocation mechanism allows a client to invalidate its tokens if the end-user logs out, changes identity, or uninstalls the respective application. Notifying the authorization server that the token is no longer needed allows the authorization server to clean up data associated with that token (e.g., session data) and the underlying authorization grant. This behavior prevents a situation in which there is still a valid authorization grant for a particular client of which the end-user is not aware. This way, token revocation prevents abuse of abandoned tokens and facilitates a better end-user experience since invalidated authorization grants will no longer turn up in a list of authorization grants the authorization server might present to the end-user.


1.1. Requirements Language
1.1. 要件言語

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119 [RFC2119].

このドキュメントのキーワード「MUST」、「MUST NOT」、「REQUIRED」、「SHALL」、「SHALL NOT」、「SHOULD」、「SHOULD NOT」、「RECOMMENDED」、「MAY」、および「OPTIONAL」は、 RFC 2119 [RFC2119]で説明されているように解釈されます。

2. Token Revocation
2. トークンの取り消し

Implementations MUST support the revocation of refresh tokens and SHOULD support the revocation of access tokens (see Implementation Note).


The client requests the revocation of a particular token by making an HTTP POST request to the token revocation endpoint URL. This URL MUST conform to the rules given in [RFC6749], Section 3.1. Clients MUST verify that the URL is an HTTPS URL.

クライアントは、トークン失効エンドポイントURLにHTTP POST要求を行うことにより、特定のトークンの失効を要求します。このURLは、[RFC6749]のセクション3.1に記載されているルールに準拠している必要があります。クライアントは、URLがHTTPS URLであることを確認する必要があります。

The means to obtain the location of the revocation endpoint is out of the scope of this specification. For example, the client developer may consult the server's documentation or automatic discovery may be used. As this endpoint is handling security credentials, the endpoint location needs to be obtained from a trustworthy source.


Since requests to the token revocation endpoint result in the transmission of plaintext credentials in the HTTP request, URLs for token revocation endpoints MUST be HTTPS URLs. The authorization server MUST use Transport Layer Security (TLS) [RFC5246] in a version compliant with [RFC6749], Section 1.6. Implementations MAY also support additional transport-layer security mechanisms that meet their security requirements.

トークン失効エンドポイントへのリクエストはHTTPリクエストでプレーンテキスト認証情報を送信するため、トークン失効エンドポイントのURLはHTTPS URLでなければなりません。認可サーバーは、[RFC6749]、セクション1.6に準拠したバージョンでトランスポート層セキュリティ(TLS)[RFC5246]を使用する必要があります。実装は、セキュリティ要件を満たす追加のトランスポート層セキュリティメカニズムもサポートする場合があります。

If the host of the token revocation endpoint can also be reached over HTTP, then the server SHOULD also offer a revocation service at the corresponding HTTP URI, but it MUST NOT publish this URI as a token revocation endpoint. This ensures that tokens accidentally sent over HTTP will be revoked.

トークン失効エンドポイントのホストにもHTTP経由で到達できる場合、サーバーは対応するHTTP URIで失効サービスも提供する必要があります(SHOULD)が、このURIをトークン失効エンドポイントとして公開してはなりません(MUST NOT)。これにより、誤ってHTTP経由で送信されたトークンが確実に取り消されます。

2.1. Revocation Request
2.1. 失効リクエスト

The client constructs the request by including the following parameters using the "application/x-www-form-urlencoded" format in the HTTP request entity-body:

クライアントは、HTTPリクエストのエンティティ本体に「application / x-www-form-urlencoded」形式を使用して次のパラメータを含めることにより、リクエストを作成します。

token REQUIRED. The token that the client wants to get revoked.


token_type_hint OPTIONAL. A hint about the type of the token submitted for revocation. Clients MAY pass this parameter in order to help the authorization server to optimize the token lookup. If the server is unable to locate the token using the given hint, it MUST extend its search across all of its supported token types. An authorization server MAY ignore this parameter, particularly if it is able to detect the token type automatically. This specification defines two such values:


* access_token: An access token as defined in [RFC6749], Section 1.4

* access_token:[RFC6749]、セクション1.4で定義されているアクセストークン

* refresh_token: A refresh token as defined in [RFC6749], Section 1.5

* refresh_token:[RFC6749]のセクション1.5で定義されている更新トークン

Specific implementations, profiles, and extensions of this specification MAY define other values for this parameter using the registry defined in Section 4.1.2.


The client also includes its authentication credentials as described in Section 2.3. of [RFC6749].

セクション2.3で説明されているように、クライアントには認証資格情報も含まれています。 [RFC6749]の。

For example, a client may request the revocation of a refresh token with the following request:


     POST /revoke HTTP/1.1
     Content-Type: application/x-www-form-urlencoded
     Authorization: Basic czZCaGRSa3F0MzpnWDFmQmF0M2JW


token = 45ghiukldjahdnhzdauz&token_type_hint = refresh_token

The authorization server first validates the client credentials (in case of a confidential client) and then verifies whether the token was issued to the client making the revocation request. If this validation fails, the request is refused and the client is informed of the error by the authorization server as described below.


In the next step, the authorization server invalidates the token. The invalidation takes place immediately, and the token cannot be used again after the revocation. In practice, there could be a propagation delay, for example, in which some servers know about the invalidation while others do not. Implementations should minimize that window, and clients must not try to use the token after receipt of an HTTP 200 response from the server.

次のステップでは、許可サーバーがトークンを無効にします。無効化はすぐに行われ、失効後にトークンを再び使用することはできません。実際には、伝播遅延が発生する可能性があります。たとえば、一部のサーバーは無効化を認識しているが、他のサーバーは認識していない場合があります。実装はそのウィンドウを最小化する必要があり、クライアントはサーバーからのHTTP 200応答の受信後にトークンを使用してはなりません。

Depending on the authorization server's revocation policy, the revocation of a particular token may cause the revocation of related tokens and the underlying authorization grant. If the particular token is a refresh token and the authorization server supports the revocation of access tokens, then the authorization server SHOULD also invalidate all access tokens based on the same authorization grant (see Implementation Note). If the token passed to the request is an access token, the server MAY revoke the respective refresh token as well.


Note: A client compliant with [RFC6749] must be prepared to handle unexpected token invalidation at any time. Independent of the revocation mechanism specified in this document, resource owners may revoke authorization grants, or the authorization server may invalidate tokens in order to mitigate security threats. Thus, having different server policies with respect to cascading the revocation of tokens should not pose interoperability problems.


2.2. Revocation Response
2.2. 失効応答

The authorization server responds with HTTP status code 200 if the token has been revoked successfully or if the client submitted an invalid token.


Note: invalid tokens do not cause an error response since the client cannot handle such an error in a reasonable way. Moreover, the purpose of the revocation request, invalidating the particular token, is already achieved.


The content of the response body is ignored by the client as all necessary information is conveyed in the response code.


An invalid token type hint value is ignored by the authorization server and does not influence the revocation response.


2.2.1. Error Response
2.2.1. エラー応答

The error presentation conforms to the definition in Section 5.2 of [RFC6749]. The following additional error code is defined for the token revocation endpoint:


unsupported_token_type: The authorization server does not support the revocation of the presented token type. That is, the client tried to revoke an access token on a server not supporting this feature.


If the server responds with HTTP status code 503, the client must assume the token still exists and may retry after a reasonable delay. The server may include a "Retry-After" header in the response to indicate how long the service is expected to be unavailable to the requesting client.

サーバーがHTTPステータスコード503で応答する場合、クライアントはトークンがまだ存在していると想定する必要があり、妥当な遅延の後に再試行する可能性があります。サーバーは、応答に "Retry-After"ヘッダーを含めて、要求しているクライアントがサービスを利用できないと予想される期間を示すことができます。

2.3. Cross-Origin Support
2.3. クロスオリジンサポート

The revocation endpoint MAY support Cross-Origin Resource Sharing (CORS) [W3C.WD-cors-20120403] if it is aimed at use in combination with user-agent-based applications.


In addition, for interoperability with legacy user-agents, it MAY also offer JSONP (Remote JSON - JSONP) [jsonp] by allowing GET requests with an additional parameter:


callback OPTIONAL. The qualified name of a JavaScript function.

コールバックオプション。 JavaScript関数の修飾名。

For example, a client may request the revocation of an access token with the following request (line breaks are for display purposes only):


Successful response:




Error response:



Clients should be aware that when relying on JSONP, a malicious revocation endpoint may attempt to inject malicious code into the client.


3. Implementation Note
3. 実装ノート

OAuth 2.0 allows deployment flexibility with respect to the style of access tokens. The access tokens may be self-contained so that a resource server needs no further interaction with an authorization server issuing these tokens to perform an authorization decision of the client requesting access to a protected resource. A system design may, however, instead use access tokens that are handles referring to authorization data stored at the authorization server. This consequently requires a resource server to issue a request to the respective authorization server to retrieve the content of the access token every time a client presents an access token.

OAuth 2.0では、アクセストークンのスタイルに関して柔軟な導入が可能です。アクセストークンは自己完結型であるため、リソースサーバーは、保護されたリソースへのアクセスを要求するクライアントの承認決定を実行するために、これらのトークンを発行する承認サーバーとのさらなる対話を必要としません。ただし、システム設計では、認証サーバーに格納されている認証データを参照するハンドルであるアクセストークンを代わりに使用できます。このため、クライアントがアクセストークンを提示するたびに、リソースサーバーがそれぞれの承認サーバーにリクエストを発行して、アクセストークンのコンテンツを取得する必要があります。

While these are not the only options, they illustrate the implications for revocation. In the latter case, the authorization server is able to revoke an access token previously issued to a client when the resource server relays a received access token. In the former case, some (currently non-standardized) backend interaction between the authorization server and the resource server may be used when immediate access token revocation is desired. Another design alternative is to issue short-lived access tokens, which can be refreshed at any time using the corresponding refresh tokens. This allows the authorization server to impose a limit on the time revoked when access tokens are in use.


Which approach of token revocation is chosen will depend on the overall system design and on the application service provider's risk analysis. The cost of revocation in terms of required state and communication overhead is ultimately the result of the desired security properties.


4. IANA Considerations
4. IANAに関する考慮事項

This specification registers an error value in the "OAuth Extensions Error Registry" and establishes the "OAuth Token Type Hints" registry.


4.1. OAuth Extensions Error Registration
4.1. OAuth拡張エラー登録

This specification registers the following error value in the "OAuth Extensions Error Registry" defined in [RFC6749].


4.1.1. The "unsupported_token_type" Error Value
4.1.1. 「unsupported_token_type」エラー値

Error name: unsupported_token_type


Error Usage Location: Revocation endpoint error response


Related Protocol Extension: Token Revocation Endpoint


Change controller: IETF


Specification document(s): [RFC7009]


4.1.2. OAuth Token Type Hints Registry
4.1.2. OAuthトークンタイプヒントレジストリ

This specification establishes the "OAuth Token Type Hints" registry. Possible values of the parameter "token_type_hint" (see Section 2.1) are registered with a Specification Required ([RFC5226]) after a two-week review period on the mailing list, on the advice of one or more Designated Experts. However, to allow for the allocation of values prior to publication, the Designated Expert(s) may approve registration once they are satisfied that such a specification will be published. Registration requests must be sent to the mailing list for review and comment, with an appropriate subject (e.g., "Request for parameter: example"). Within the review period, the Designated Expert(s) will either approve or deny the registration request, communicating this decision to the review list and IANA. Denials should include an explanation and, if applicable, suggestions as to how to make the request successful. IANA must only accept registry updates from the Designated Expert(s) and should direct all requests for registration to the review mailing list.

この仕様は、「OAuthトークンタイプヒント」レジストリを確立します。パラメータ「token_type_hint」(セクション2.1を参照)の可能な値は、oauth-ext-review @ ietf.orgメーリングリストの2週間のレビュー期間後に、1つのアドバイスに従って、必要な仕様([RFC5226])に登録されます。以上の指定専門家。ただし、公開前の値の割り当てを可能にするために、指定された専門家は、そのような仕様が公開されることに納得したら、登録を承認することができます。登録リクエストは、適切な件名(例:「パラメーターのリクエスト:例」)とともに、レビューとコメントのためにoauth-ext-review@ietf.orgメーリングリストに送信する必要があります。レビュー期間内に、指定専門家は登録リクエストを承認または拒否し、この決定をレビューリストとIANAに通知します。拒否には、要求を成功させる方法についての説明と、該当する場合は提案を含める必要があります。 IANAは、指定された専門家からのレジストリの更新のみを受け入れ、登録のすべてのリクエストをレビューメーリングリストに転送する必要があります。 Registration Template 登録テンプレート

Hint Value: The additional value, which can be used to indicate a certain token type to the authorization server.


Change controller: For Standards Track RFCs, state "IETF". For others, give the name of the responsible party. Other details (e.g., postal address, email address, and home page URI) may also be included.

コントローラーの変更:Standards Track RFCの場合は、「IETF」と記載します。その他の場合は、責任者の名前を入力してください。その他の詳細(例:住所、電子メールアドレス、ホームページURI)も含まれる場合があります。

Specification document(s): Reference to the document(s) that specifies the type, preferably including a URI that can be used to retrieve a copy of the document(s). An indication of the relevant sections may also be included but is not required.

仕様ドキュメント:タイプを指定するドキュメントへの参照。できればドキュメントのコピーを取得するために使用できるURIを含むことが望ましい。関連セクションの表示も含まれる場合がありますが、必須ではありません。 Initial Registry Contents レジストリの初期内容

The OAuth Token Type Hint registry's initial contents are as follows.


             |   Hint Value  | Change Controller | Reference |
             |  access_token |        IETF       | [RFC7009] |
             | refresh_token |        IETF       | [RFC7009] |

Table 1: OAuth Token Type Hints initial registry contents


5. Security Considerations
5. セキュリティに関する考慮事項

If the authorization server does not support access token revocation, access tokens will not be immediately invalidated when the corresponding refresh token is revoked. Deployments must take this into account when conducting their security risk analysis.


Cleaning up tokens using revocation contributes to overall security and privacy since it reduces the likelihood for abuse of abandoned tokens. This specification in general does not intend to provide countermeasures against token theft and abuse. For a discussion of respective threats and countermeasures, consult the security considerations given in Section 10 of the OAuth core specification [RFC6749] and the OAuth threat model document [RFC6819].


Malicious clients could attempt to use the new endpoint to launch denial-of-service attacks on the authorization server. Appropriate countermeasures, which should be in place for the token endpoint as well, MUST be applied to the revocation endpoint (see [RFC6819], Section Specifically, invalid token type hints may misguide the authorization server and cause additional database lookups. Care MUST be taken to prevent malicious clients from exploiting this feature to launch denial-of-service attacks.


A malicious client may attempt to guess valid tokens on this endpoint by making revocation requests against potential token strings. According to this specification, a client's request must contain a valid client_id, in the case of a public client, or valid client credentials, in the case of a confidential client. The token being revoked must also belong to the requesting client. If an attacker is able to successfully guess a public client's client_id and one of their tokens, or a private client's credentials and one of their tokens, they could do much worse damage by using the token elsewhere than by revoking it. If they chose to revoke the token, the legitimate client will lose its authorization grant and will need to prompt the user again. No further damage is done and the guessed token is now worthless.


Since the revocation endpoint is handling security credentials, clients need to obtain its location from a trustworthy source only. Otherwise, an attacker could capture valid security tokens by utilizing a counterfeit revocation endpoint. Moreover, in order to detect counterfeit revocation endpoints, clients MUST authenticate the revocation endpoint (certificate validation, etc.).


6. Acknowledgements
6. 謝辞

We would like to thank Peter Mauritius, Amanda Anganes, Mark Wubben, Hannes Tschofenig, Michiel de Jong, Doug Foiles, Paul Madsen, George Fletcher, Sebastian Ebling, Christian Stuebner, Brian Campbell, Igor Faynberg, Lukas Rosenstock, and Justin Richer for their valuable feedback.

Peter Mauritius、Amanda Anganes、Mark Wubben、Hannes Tschofenig、Michiel de Jong、Doug Foiles、Paul Madsen、George Fletcher、Sebastian Ebling、Christian Stuebner、Brian Campbell、Igor Faynberg、Lukas Rosenstock、Justin Richerに感謝します。貴重なフィードバック。

7. References
7. 参考文献
7.1. Normative References
7.1. 引用文献

[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997.

[RFC2119] Bradner、S。、「要件レベルを示すためにRFCで使用するキーワード」、BCP 14、RFC 2119、1997年3月。

[RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA Considerations Section in RFCs", BCP 26, RFC 5226, May 2008.

[RFC5226] Narten、T。およびH. Alvestrand、「RFCでIANAの考慮事項セクションを作成するためのガイドライン」、BCP 26、RFC 5226、2008年5月。

[RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security (TLS) Protocol Version 1.2", RFC 5246, August 2008.

[RFC5246] Dierks、T。およびE. Rescorla、「The Transport Layer Security(TLS)Protocol Version 1.2」、RFC 5246、2008年8月。

[RFC6749] Hardt, D., "The OAuth 2.0 Authorization Framework", RFC 6749, October 2012.

[RFC6749] Hardt、D。、「The OAuth 2.0 Authorization Framework」、RFC 6749、2012年10月。

7.2. Informative References
7.2. 参考引用

[RFC6819] Lodderstedt, T., McGloin, M., and P. Hunt, "OAuth 2.0 Threat Model and Security Considerations", RFC 6819, January 2013.

[RFC6819] Lodderstedt、T.、McGloin、M。、およびP. Hunt、「OAuth 2.0脅威モデルとセキュリティの考慮事項」、RFC 6819、2013年1月。

[W3C.WD-cors-20120403] Kesteren, A., "Cross-Origin Resource Sharing", World Wide Web Consortium LastCall WD-cors-20120403, April 2012, <>.

[W3C.WD-cors-20120403] Kesteren、A。、「Cross-Origin Resource Sharing」、World Wide Web Consortium LastCall WD-cors-20120403、2012年4月、< / WD-cors-20120403>。

[jsonp] Ippolito, B., "Remote JSON - JSONP", December 2005, < remote-json-jsonp>.

[jsonp] Ippolito、B。、「Remote JSON-JSONP」、2005年12月、< remote-json-jsonp>。

Authors' Addresses


Torsten Lodderstedt (editor) Deutsche Telekom AG

Torsten Lodderstedt(編集者)Deutsche Telekom AG


Stefanie Dronia



Marius Scurtescu Google