OASIS eXtensible Access Control Markup Language (XACML) TC

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Re: [xacml] [model] Proposal of Post Condition

  • 1.  Re: [xacml] [model] Proposal of Post Condition

    Posted 02-14-2002 21:12
    Hi Kudo-san,
    
    > If <Conditions> element is used, your concern might be considered. But as I
    > wrote in the previous mail, my position is that the semantics of the
    > post-condition depends on each application. If the application uses simple
    > post-condition like "log", the meaning of the assertion with condition
    > differs as you described. But if the post-condition is "delete in 30days",
    > it is meaningless to wait 30days to give the grant decision to the
    > requester and I think that PEP grants the access to the request after it
    > registers the "delete in 30days" post condition to the post-condition
    > management component. In this case, there is no big difference between two
    > cases you pointed out because even if the delete operation fails after 30
    > days, there is no way to cancel the grant decision issued 30 days ago.
    > Anyway the application should deal with this exception independently. I am
    > quite optimistic that application-specific exception handling can solve
    > this kind of problems.
    
    You mean that post-conditions are just informative (as you wrote) and
    they don't affect the validity of the assertion like the example of
    "delete in 30days".
    Then I don't like see them in <Conditions> element.
    
    When we put post-conditions in <Conditions> element, we must extend
    SAML <Condition> element (I noticed it today). Then how about
    extending SAML <AuthorizationDecisionStatement> element? SAML allows
    to extend it.
    It will look like as follows:
    
    <element name="AuthorizationDecisionWithPostConditionStatement"
        type="xacml:AuthorizationDecisionWithPostConditionStatementType"/>
    <complexType name="AuthorizationDecisionWithPostConditionStatementType">
      <complexContent>
        <extension base="saml:AuthorizationDecisionStatementType">
          <sequence>
            <element ref="xacml:PostConditions"/>
          </sequence>
        </extension>
      </complexContent>
    </complexType>
    
    
    Regards,
    Toshi
    ---
    NISHIMURA Toshihiro (FAMILY Given)
    nishimura.toshi@jp.fujitsu.com
    XML Application Technology Dept., PROJECT-A XML, FUJITSU LIMITED