the saml token profile depends on non-global attributes in keyidentifier/wsse schema does not support keyIdentifier element extensibility

The schema for wsse:KeyIdentifier does not support element extensibility.

The SAML token profile relies on non-global saml attributes (i.e. 
saml:local
and saml:binding) to format keyIdentifier SecurityTokenReferences.

The non-global attributes could be replaced with the global 
saml:AuthorityBinding
element, if the wsse:KeyIdentifier supported element extensibility.

There are 2 paths forward.

. Modify the wsse:schema to allow any element to be included in 
keyIdentifiers

. use Direct References with  an optional contained AuthorityBinding element
  to reference SAML assertions, when the authority and binding must be 
sepcified
  to acquire the assertion.

I am working on modifying the profile to take the latter approach, but would
appreciate feedback from the TC.

Any comments?

Ron

<xsd:complexType name="KeyIdentifierType">
-
    <xsd:annotation>
<xsd:documentation>A security token key identifier</xsd:documentation>
</xsd:annotation>
-
    <xsd:simpleContent>
-
    <xsd:extension base="wsse:EncodedString">
<xsd:attribute name="ValueType" type="xsd:anyURI"/>
</xsd:extension>
</xsd:simpleContent>
</xsd:complexType>

Ron Monzillo wrote:

> BTW, in section 3.3, we need to change the way SAML keyIdentifier 
> references
> are composed, as the Binding and Location attributes are not global. 
> Perhaps we can
> use the SAML AuthorityBinding construct, as apposed to its internal 
> attributes.