--- 1/draft-ietf-oauth-saml2-bearer-14.txt 2012-11-07 16:14:49.877427988 +0100 +++ 2/draft-ietf-oauth-saml2-bearer-15.txt 2012-11-07 16:14:49.905456328 +0100 @@ -1,19 +1,19 @@ OAuth Working Group B. Campbell Internet-Draft Ping Identity Intended status: Standards Track C. Mortimore -Expires: March 18, 2013 Salesforce - September 14, 2012 +Expires: May 11, 2013 Salesforce + November 7, 2012 SAML 2.0 Bearer Assertion Profiles for OAuth 2.0 - draft-ietf-oauth-saml2-bearer-14 + draft-ietf-oauth-saml2-bearer-15 Abstract This specification defines the use of a SAML 2.0 Bearer Assertion as a means for requesting an OAuth 2.0 access token as well as for use as a means of client authentication. Status of this Memo This Internet-Draft is submitted in full conformance with the @@ -22,21 +22,21 @@ Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." - This Internet-Draft will expire on March 18, 2013. + This Internet-Draft will expire on May 11, 2013. Copyright Notice Copyright (c) 2012 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents @@ -56,46 +56,46 @@ 2.2. Using SAML Assertions for Client Authentication . . . . . 5 3. Assertion Format and Processing Requirements . . . . . . . . . 6 3.1. Authorization Grant Processing . . . . . . . . . . . . . . 8 3.2. Client Authentication Processing . . . . . . . . . . . . . 8 4. Authorization Grant Example . . . . . . . . . . . . . . . . . 9 5. Security Considerations . . . . . . . . . . . . . . . . . . . 10 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10 6.1. Sub-Namespace Registration of urn:ietf:params:oauth:grant-type:saml2-bearer . . . . . . 10 6.2. Sub-Namespace Registration of - urn:ietf:params:oauth:client-assertion-type:saml2-bearer . 11 + urn:ietf:params:oauth:client-assertion-type:saml2-bearer . 10 7. References . . . . . . . . . . . . . . . . . . . . . . . . . . 11 7.1. Normative References . . . . . . . . . . . . . . . . . . . 11 - 7.2. Informative References . . . . . . . . . . . . . . . . . . 12 + 7.2. Informative References . . . . . . . . . . . . . . . . . . 11 Appendix A. Acknowledgements . . . . . . . . . . . . . . . . . . 12 Appendix B. Document History . . . . . . . . . . . . . . . . . . 12 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 17 1. Introduction The Security Assertion Markup Language (SAML) 2.0 [OASIS.saml-core-2.0-os] is an XML-based framework that allows identity and security information to be shared across security domains. The SAML specification, while primarily targeted at providing cross domain Web browser single sign-on, was also designed to be modular and extensible to facilitate use in other contexts. The Assertion, an XML security token, is a fundamental construct of SAML that is often adopted for use in other protocols and specifications. An Assertion is generally issued by an identity provider and consumed by a service provider who relies on its content to identify the Assertion's subject for security related purposes. - The OAuth 2.0 Authorization Protocol [I-D.ietf-oauth-v2] provides a - method for making authenticated HTTP requests to a resource using an - access token. Access tokens are issued to third-party clients by an + The OAuth 2.0 Authorization Protocol [RFC6749] provides a method for + making authenticated HTTP requests to a resource using an access + token. Access tokens are issued to third-party clients by an authorization server (AS) with the (sometimes implicit) approval of the resource owner. In OAuth, an authorization grant is an abstract term used to describe intermediate credentials that represent the resource owner authorization. An authorization grant is used by the client to obtain an access token. Several authorization grant types are defined to support a wide range of client types and user experiences. OAuth also allows for the definition of new extension grant types to support additional clients or to provide a bridge between OAuth and other trust frameworks. Finally, OAuth allows the definition of additional authentication mechanisms to be used by @@ -143,23 +143,23 @@ 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]. Unless otherwise noted, all the protocol parameter names and values are case sensitive. 1.2. Terminology All terms are as defined in The OAuth 2.0 Authorization Protocol - [I-D.ietf-oauth-v2], OAuth 2.0 Assertion Profile - [I-D.ietf-oauth-assertions], and Security Assertion Markup Language - (SAML) 2.0 [OASIS.saml-core-2.0-os]. + [RFC6749], OAuth 2.0 Assertion Profile [I-D.ietf-oauth-assertions], + and Security Assertion Markup Language (SAML) 2.0 + [OASIS.saml-core-2.0-os]. 2. HTTP Parameter Bindings for Transporting Assertions The OAuth 2.0 Assertion Profile [I-D.ietf-oauth-assertions] defines generic HTTP parameters for transporting Assertions during interactions with a token endpoint. This section defines the values of those parameters for use with SAML 2.0 Bearer Assertions. 2.1. Using SAML Assertions as Authorization Grants @@ -184,22 +184,22 @@ POST /token.oauth2 HTTP/1.1 Host: as.example.com Content-Type: application/x-www-form-urlencoded grant_type=urn%3Aietf%3Aparams%3Aoauth%3Agrant-type%3Asaml2-bearer& assertion=PHNhbWxwOl...[omitted for brevity]...ZT4 2.2. Using SAML Assertions for Client Authentication - To use a SAML Bearer Assertion for client authentication grant, use - the following parameter values and encodings. + To use a SAML Bearer Assertion for client authentication, use the + following parameter values and encodings. The value of the "client_assertion_type" parameter MUST be "urn:ietf:params:oauth:client-assertion-type:saml2-bearer". The value of the "client_assertion" parameter MUST contain a single SAML 2.0 Assertion. The SAML Assertion XML data MUST be encoded using base64url, where the encoding adheres to the definition in Section 5 of RFC4648 [RFC4648] and where the padding bits are set to zero. To avoid the need for subsequent encoding steps (by "application/x-www-form-urlencoded" [W3C.REC-html401-19991224], for @@ -217,25 +217,25 @@ grant_type=authorization_code& code=vAZEIHjQTHuGgaSvyW9hO0RpusLzkvTOww3trZBxZpo& client_assertion_type=urn%3Aietf%3Aparams%3Aoauth %3Aclient-assertion-type%3Asaml2-bearer& client_assertion=PHNhbW...[omitted for brevity]...ZT 3. Assertion Format and Processing Requirements In order to issue an access token response as described in The OAuth - 2.0 Authorization Protocol [I-D.ietf-oauth-v2] or to rely on an - Assertion for client authentication, the authorization server MUST - validate the Assertion according to the criteria below. Application - of additional restrictions and policy are at the discretion of the - authorization server. + 2.0 Authorization Protocol [RFC6749] or to rely on an Assertion for + client authentication, the authorization server MUST validate the + Assertion according to the criteria below. Application of additional + restrictions and policy are at the discretion of the authorization + server. o The Assertion's element MUST contain a unique identifier for the entity that issued the Assertion. o The Assertion MUST contain element with an element with an element containing a URI reference that identifies the authorization server, or the service provider SAML entity of its controlling domain, as an intended audience. The token endpoint URL of the authorization server MAY be used as an acceptable value for an @@ -317,45 +317,45 @@ element including the NotOnOrAfter and NotBefore attributes, rejecting unknown condition types, etc. 3.1. Authorization Grant Processing If present, the authorization server MUST also validate the client credentials. If the Assertion is not valid, or its subject confirmation requirements cannot be met, the authorization server MUST construct - an error response as defined in OAuth 2.0 [I-D.ietf-oauth-v2]. The - value of the "error" parameter MUST be the "invalid_grant" error - code. The authorization server MAY include additional information - regarding the reasons the Assertion was considered invalid using the + an error response as defined in OAuth 2.0 [RFC6749]. The value of + the "error" parameter MUST be the "invalid_grant" error code. The + authorization server MAY include additional information regarding the + reasons the Assertion was considered invalid using the "error_description" or "error_uri" parameters. For example: HTTP/1.1 400 Bad Request Content-Type: application/json Cache-Control: no-store { "error":"invalid_grant", "error_description":"Audience validation failed" } 3.2. Client Authentication Processing If the client Assertion is not valid, or its subject confirmation requirements cannot be met, the authorization server MUST construct - an error response as defined in OAuth 2.0 [I-D.ietf-oauth-v2]. The - value of the "error" parameter MUST be the "invalid_client" error - code. The authorization server MAY include additional information - regarding the reasons the Assertion was considered invalid using the + an error response as defined in OAuth 2.0 [RFC6749]. The value of + the "error" parameter MUST be the "invalid_client" error code. The + authorization server MAY include additional information regarding the + reasons the Assertion was considered invalid using the "error_description" or "error_uri" parameters. 4. Authorization Grant Example Though non-normative, the following examples illustrate what a conforming Assertion and access token request would look like. Below is an example SAML 2.0 Assertion (whitespace formatting is for display purposes only): @@ -406,92 +406,88 @@ grant_type=urn%3Aietf%3Aparams%3Aoauth%3Agrant-type%3Asaml2- bearer&assertion=PEFzc2VydGlvbiBJc3N1ZUluc3RhbnQ9IjIwMTEtMDU [...omitted for brevity...]aG5TdGF0ZW1lbnQ-PC9Bc3NlcnRpb24- Figure 2: Example Request 5. Security Considerations No additional security considerations apply beyond those described - within The OAuth 2.0 Authorization Protocol [I-D.ietf-oauth-v2], the - OAuth 2.0 Assertion Profile [I-D.ietf-oauth-assertions], and in the - Security and Privacy Considerations for the OASIS Security Assertion - Markup Language (SAML) V2.0 [OASIS.saml-sec-consider-2.0-os]. + within The OAuth 2.0 Authorization Protocol [RFC6749], the OAuth 2.0 + Assertion Profile [I-D.ietf-oauth-assertions], and in the Security + and Privacy Considerations for the OASIS Security Assertion Markup + Language (SAML) V2.0 [OASIS.saml-sec-consider-2.0-os]. 6. IANA Considerations 6.1. Sub-Namespace Registration of urn:ietf:params:oauth:grant-type:saml2-bearer This is a request to IANA to please register the value "grant-type:saml2-bearer" in the registry urn:ietf:params:oauth - established in An IETF URN Sub-Namespace for OAuth - [I-D.ietf-oauth-urn-sub-ns]. + established in An IETF URN Sub-Namespace for OAuth [RFC6755]. o URN: urn:ietf:params:oauth:grant-type:saml2-bearer o Common Name: SAML 2.0 Bearer Assertion Grant Type Profile for OAuth 2.0 o Change controller: IETF o Specification Document: [[this document]] 6.2. Sub-Namespace Registration of urn:ietf:params:oauth:client-assertion-type:saml2-bearer This is a request to IANA to please register the value "client-assertion-type:saml2-bearer" in the registry urn:ietf:params:oauth established in An IETF URN Sub-Namespace for - OAuth [I-D.ietf-oauth-urn-sub-ns]. + OAuth [RFC6755]. o URN: urn:ietf:params:oauth:client-assertion-type:saml2-bearer o Common Name: SAML 2.0 Bearer Assertion Profile for OAuth 2.0 Client Authentication o Change controller: IETF o Specification Document: [[this document]] 7. References 7.1. Normative References [I-D.ietf-oauth-assertions] Campbell, B., Mortimore, C., Jones, M., and Y. Goland, "Assertion Framework for OAuth 2.0", - draft-ietf-oauth-assertions-05 (work in progress), + draft-ietf-oauth-assertions-06 (work in progress), September 2012. - [I-D.ietf-oauth-urn-sub-ns] - Campbell, B. and H. Tschofenig, "An IETF URN Sub-Namespace - for OAuth", draft-ietf-oauth-urn-sub-ns-06 (work in - progress), July 2012. - - [I-D.ietf-oauth-v2] - Hardt, D., "The OAuth 2.0 Authorization Framework", - draft-ietf-oauth-v2-31 (work in progress), August 2012. - [OASIS.saml-core-2.0-os] Cantor, S., Kemp, J., Philpott, R., and E. Maler, "Assertions and Protocol for the OASIS Security Assertion Markup Language (SAML) V2.0", OASIS Standard saml-core- 2.0-os, March 2005. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC4648] Josefsson, S., "The Base16, Base32, and Base64 Data Encodings", RFC 4648, October 2006. + [RFC6749] Hardt, D., "The OAuth 2.0 Authorization Framework", + RFC 6749, October 2012. + + [RFC6755] Campbell, B. and H. Tschofenig, "An IETF URN Sub-Namespace + for OAuth", RFC 6755, October 2012. + 7.2. Informative References [OASIS.saml-deleg-cs] Cantor, S., Ed., "SAML V2.0 Condition for Delegation Restriction", Nov 2009. [OASIS.saml-profiles-2.0-os] Hughes, J., Cantor, S., Hodges, J., Hirsch, F., Mishra, P., Philpott, R., and E. Maler, "Profiles for the OASIS Security Assertion Markup Language (SAML) V2.0", OASIS @@ -515,28 +511,38 @@ document: Paul Madsen, Patrick Harding, Peter Motykowski, Eran Hammer, Peter Saint-Andre, Ian Barnett, Eric Fazendin, Torsten Lodderstedt, Susan Harper, Scott Tomilson, Scott Cantor, Michael B. Jones, Hannes Tschofenig, David Waite, Phil Hunt, and Mukesh Bhatnagar. Appendix B. Document History [[ to be removed by RFC editor before publication as an RFC ]] + draft-ietf-oauth-saml2-bearer-15 + + o Reference RFC 6749 and RFC 6755. + + o Update draft-ietf-oauth-assertions reference to -06. + + o Remove extraneous word per + http://www.ietf.org/mail-archive/web/oauth/current/msg10055.html + draft-ietf-oauth-saml2-bearer-14 o Add more text to intro explaining that an assertion grant type can be used with or without client authentication/identification and that client assertion authentication is nothing more than an alternative way for a client to authenticate to the token endpoint o Add examples to Sections 2.1 and 2.2 + o Update references draft-ietf-oauth-saml2-bearer-13 o Update references: oauth-assertions-04, oauth-urn-sub-ns-05, oauth -28 o Changed "Description" to "Specification Document" in both registration requests in IANA Considerations per changes to the template in ietf-oauth-urn-sub-ns(-03)