- From: Asir Vedamuthu <asirveda@microsoft.com>
- Date: Fri, 11 Aug 2006 16:54:41 -0700
- To: "Yalcinalp, Umit" <umit.yalcinalp@sap.com>, <public-ws-policy@w3.org>
> We could also add a note in the framework/primer when it is not > desirable to use xml:id but rely on wsu:id Good point. The xml:id Version 1.0 specification says, 'The Canonical XML Version 1.0 specification describes a process whereby attributes in the xml: namespace are inherited in a canonicalized document. While this produces a reasonable result with xml:lang or xml:space attributes, processing xml:id attributes in this way is likely to produce documents that contain xml:id errors, specifically xml:id attribute values that are not unique.'[1] An illustrative description of the above technical issue can be found in [2]. The XML Core Working Group is chartered [3] to produce a new version of Canonical XML to address this inconsistency. 'XML Signature Syntax and Processing' requires implementations to support C14N 1.0 [4]. C14N 1.0 is widely supported [5] and used. In many cases, users only have access to C14N 1.0 support. If the WG wants to adopt the xml:id attribute in addition to the wsu:Id attribute, we suggest amending the proposal to include the following note of caution to Section 4.2: "The use of xml:id attribute in conjunction with Canonical XML 1.0 is inappropriate as described in Appendix C of xml:id Version 1.0 [XMLID] and thus this combination must be avoided (see [C14NNOTE]). For example, a policy expression identified using xml:id attribute should not be signed using XML Digital Signature when Canonical XML 1.0 is being used as the canonicalization method." Where, C14NNOTE is a non-normative reference to [2]. [1] http://www.w3.org/TR/2005/REC-xml-id-20050909/#impact [2] http://www.w3.org/2006/04/c14n-note/c14n-note.html#S3 [3] http://www.w3.org/2005/02/xml-core-wg-charter.html#deliverables [4] http://www.w3.org/TR/2002/REC-xmldsig-core-20020212/#sec-c14nAlg [5] http://www.w3.org/Signature/2001/04/05-xmldsig-interop.html http://www.w3.org/Signature/2000/10/10-c14n-interop.html Regards, Asir S Vedamuthu Microsoft Corporation ________________________________________ From: public-ws-policy-request@w3.org [mailto:public-ws-policy-request@w3.org] On Behalf Of Yalcinalp, Umit Sent: Tuesday, July 25, 2006 1:54 PM To: public-ws-policy@w3.org Subject: NEW ISSUE: The framework specification should enable usage of xml:id Title: The framework specification should also enable the usage of xml:id Description: The WS-Policy Framework specification uses wsu:id element to designate identification for elements[WS-Policy]. W3C also published xml:id document that allows the same use [XMLID] that is a recommendation. Currently, the WS-Policy specification does not use the xml:id mechanism for uniquely identifying XML elements and relies on the WSS definition of id mechanism. Justification: The purpose of the xml:id specification is to have unique element identifiers to be recognized by all conformant XML processors. Currently, WS-Policy relies on WS-Security specification for generating URI references instead and requires the framework providers to recognize this alternate mechanism for processing references. As xml:id will be adopted, the support of xml:id in all XML processors may require WS-Policy to also allow utilization of xml:id. Further, the specification does not clarify whether the xml:id is permissable as an identification mechanism for a WS-Policy expression. Target: Section 4.2 of the WS-Policy, Appendix A. Proposal: Allow xml:id as a permissible mechanism for identifying policy expressions in addition to wsu:Id 1. Replace {/wsp:Policy/@wsu:Id The identity of the policy expression as an ID within the enclosing XML document. If omitted, there is no implied value. To refer to this policy expression, a URI-reference MAY be formed using this value per Section 4.2 of WS-Security [WS-Security 2004].} With /wsp:Policy/{@wsu:Id | @xml:id} The identity of the policy expression as an ID within the enclosing XML document. If omitted, there is no implied value. To refer to this policy expression, a URI-reference MAY be formed using this value per Section 4.2 of WS-Security [WS-Security 2004] when @wsu:Id is used. 2. Repeat last example in Section 4.2 using xml:id in addition to wsu:id (last paragraph of Section 4.2) to illustrate the form. This is purely editorial. 3. Add normative reference to xml:id [XMLID] in A.1. Personal Note: I have chosen to retain the reference on wsu:Id given the expected schedule of the publication rather than removing it due to existing support on this attribute in the existing implementations. We could also add a note in the framework/primer when it is not desirable to use xml:id but rely on wsu:id if the wg feels that is necessary. --umit [XMLID] http://www.w3.org/TR/xml-id/ [WS-Policy] http://dev.w3.org/cvsweb/~checkout~/2006/ws/policy/ws-policy-framework.html?content-type=text/html;%20charset=utf-8 ---------------------- Dr. Umit Yalcinalp Architect NetWeaver Industry Standards SAP Labs, LLC Email: umit.yalcinalp@sap.com Tel: (650) 320-3095 SDN: https://www.sdn.sap.com/irj/sdn/weblogs?blog=/pub/u/36238
Received on Friday, 11 August 2006 23:54:55 UTC