OASIS eXtensible Access Control Markup Language (XACML) TC

 View Only

Re: [xacml] Minutes for XACML TC Focus Group 19 June 2003

  • 1.  Re: [xacml] Minutes for XACML TC Focus Group 19 June 2003

    Posted 06-23-2003 04:14
    
    
    
    
    
    Questions:
    
    >> - errata 3.6:
    >>
    >> string-equality or uri equality for the subject category
    >> Proposal: not an errata, leave as is:
    >> string-equality. URI-equality implies URL-equality and this could
    >> get very complicated because URL can be url-encoded. Besides,
    >> this does not cover URN what subject attribute really is.
    
    It seems to me that
    SUN's implementation uses URI-equality
    rather than string-equality for subject-category comparison:
    
    http://sunxacml.sourceforge.net/javadoc/com/sun/xacml/EvaluationCtx.html
    http://sunxacml.sourceforge.net/javadoc/com/sun/xacml/EvaluationCtx.html#getSubjectAttribute(java.net.URI,%20java.net.URI,%20java.net.URI,%20java.net.URI)
    
    Does this comform to the specification?
    
    Maybe, the specification document should define the precise meaning of
    "string-equality".
    
    >> RECOMMENDATION: accept proposal; continue to use string-equality.
    >> The type of the XML SubjectCategory attribute is "xs:string".
    
    Does this mean the XACML schema will be changed so that
    the type of the "SubjectCategory" attribute is xs:string (not xs:anyURI) ?
    
    Satoshi Hada
    IBM Tokyo Research Laboratory
    mailto:satoshih@jp.ibm.com
    
    
    |---------+---------------------------->
    |         |           Anne Anderson    |
    |         |           <Anne.Anderson@Su|
    |         |           n.com>           |
    |         |                            |
    |         |           2003/06/20 00:09 |
    |         |           Please respond to|
    |         |           Anne.Anderson    |
    |---------+---------------------------->
      >--------------------------------------------------------------------------------------------------------------------------|
      |                                                                                                                          |
      |       To:       XACML TC <xacml@lists.oasis-open.org>                                                                    |
      |       cc:                                                                                                                |
      |       Subject:  [xacml] Minutes for XACML TC Focus Group 19 June 2003                                                    |
      |                                                                                                                          |
      |                                                                                                                          |
      >--------------------------------------------------------------------------------------------------------------------------|
    
    
    
    XACML TC Focus Group 19 June 2003 10am EDT
    Topic: Errata against XACML 1.0
    
    Present: Anne Anderson (scribe), Michiharu Kudo, Simon Godik, Hal
    Lockhart, Polar Humenn, Tim Moses
    
    Agenda: http://lists.oasis-open.org/archives/xacml/200306/msg00058.html
    
    - KAVI e-mail search engine errors
    
    Simon is getting errors when he tries to use the "search" box to
    find e-mails related to a particular topic.  Anne has had the
    same problem.  Anne just submitted an error report (since she can
    find no record of having submitted this previously; maybe that is
    why she had not heard back from the OASIS webmaster :-).
    
    - errata 3.6:
    
    string-equality or uri equality for the subject category
    
    Proposal: not an errata, leave as is:
    string-equality. URI-equality implies URL-equality and this could
    get very complicated because URL can be url-encoded. Besides,
    this does not cover URN what subject attribute really is.
    
    RECOMMENDATION: accept proposal; continue to use string-equality.
    The type of the XML SubjectCategory attribute is "xs:string".
    
    - errata 3.9:
    
    <XPathVersion> element and XPath-based functions
    
    proposal: <XPathVersion> element is REQUIRED if the XACML
    enclosing policy set or policy contains <AttributeSelector>
    elements or XPath-based functions.
    
    RECOMMENDATION: accept proposal.
    
    - errata 3.10:
    
    context node for xpath expressions
    
    proposal: <xacml-context:Request> element is a context node for
    every xpath expression.
    
    RECOMMENDATION: doesn't matter except when using relative XPath
    expression.  <xacml-context:Request> element is a context node
    for every xpath expression, under our assumption that this is
    what people have already implemented and as used in conformance
    tests, so we recommend this.
    
    - errata 3.11
    
    semantics of the <attribute-assignment> children elements
    
    proposal: needs text.
    
    RECOMMENDATION: The <AttributeAssignment> element may be used in
    any way consistent with the schema syntax, which is sequence of
    "any".  The value specified SHALL be understood by the PEP, but
    is not further specified by XACML.  See Section 7.11 Obligations
    in the XACML 1.0 Specification.
    
    - errata 3.2
    
    Need definition of type unification.
    
    ACTION ITEM: Polar will draft text and send to the list.
    
    - http://lists.oasis-open.org/archives/xacml-comment/200304/msg00007.html
      how to combine multiple policy sets?
    
    > How does each policy combining algorithm defined in Appendix C
    > combine multiple policy sets
    > (and a mixed sequence of policies and policy sets)?
    >
    > Here are the links to the related discussion.
    > In my understanding, the answer is that a <PolicySet> is
    > treated exactly like a <Policy> in all the policy combining algorithms.
    
    
    RECOMMENDATION: a <PolicySet> is treated exactly like a <Policy>
    in all the policy combining algorithms.  This text should be
    added to XACML 1.1 in some appropriate place associated with the
    combining algorithms.
    
    - http://lists.oasis-open.org/archives/xacml-comment/200305/msg00001.html
      xpath-node-match and IIIG004Policy.xml
    
    I propose the following changes: Basically, I'd like to remove
    the insufficient definition of "the enhanced XPath expression" at
    all.
    
    >>This function SHALL take two "http://www.w3.org/2001/XMLSchema#string"
    >>arguments, which SHALL be interpreted as XPath expressions and SHALL
    >>return an "http://www.w3.org/2001/XMLSchema#boolean".
    
    No change.
    
    RECOMMENDATION: agree.  No change.
    
    >>This function SHALL first extend the first argument to match
    >>an XML document in a hierarchical fashion.
    >>If a is an XPath expression and it is specified as the first argument,
    >>it SHALL be interpreted to mean match the set of nodes specified
    >>by the enhanced XPath expression "a | a//* | a//@*".
    >>In other words, the expression a SHALL match all elements and attributes
    >>below the element specified by a.
    >>This function SHALL evaluate to "True" if any XML node that matches
    >>the enhanced XPath expression is equal according to "op:node-equal"
    >>[XF Section 13.1.6] to any XML node from the node-set matched by
    >>the second argument.
    
    Replace this by the following:
    
    This function SHALL evaluate to "True"
    if either of the following two conditions is satisfied:
    (1) Any XML node from the node-set matched
    by the first argument is equal according to "op:node-equal" [XF Section
    13.1.6] to
    any XML node from the node-set matched by the second argument.
    (2) Any attribute and element node below any XML node from the node-set
    matched
    by the first argument is equal according to "op:node-equal" [XF Section
    13.1.6] to
    any XML node from the node-set matched by the second argument.
    
    NOTE1:
    The first condition is equivalent to "xpath-node-equal", and guarantees
    that "xpath-node-equal" is a special case of "xpath-node-match".
    
    RECOMMENDATION: accept replacement. (editor: make sure the [XF]
    references are to the same dated version that XACML 1.0 uses as
    its standard reference.
    
    The meeting was adjourned at 10:52am EDT.
    
    --
    Anne H. Anderson             Email: Anne.Anderson@Sun.COM
    Sun Microsystems Laboratories
    1 Network Drive,UBUR02-311     Tel: 781/442-0928
    Burlington, MA 01803-0902 USA  Fax: 781/442-1692
    
    
    You may leave a Technical Committee at any time by visiting
    http://www.oasis-open.org/apps/org/workgroup/xacml/members/leave_workgroup.php