samlp:RequestAbstractType - Trying to understand the ExtensionsType

Question

According to SAML 2.0, a RequestAbstractType is defined in the following way:

<complexType name="RequestAbstractType" abstract="true">
    <sequence>
        <element ref="saml:Issuer" minOccurs="0"/>
        <element ref="ds:Signature" minOccurs="0"/>
        <element ref="samlp:Extensions" minOccurs="0"/>
    </sequence>
    <attribute name="ID" type="ID" use="required"/>
    <attribute name="Version" type="string" use="required"/>
    <attribute name="IssueInstant" type="dateTime" use="required"/>
    <attribute name="Destination" type="anyURI" use="optional"/>
    <attribute name="Consent" type="anyURI" use="optional"/>
</complexType>

What I'm interested in is the Extensions element, which is defined as:

<element name="Extensions" type="samlp:ExtensionsType"/>

<complexType name="ExtensionsType">
    <sequence>
        <any namespace="##other" processContents="lax" maxOccurs="unbounded"/>
    </sequence>
</complexType>

How would I add/implement such an extension? I have no clue how to extend the RequestAbstractType.

Answer 1

The element allows you to include anything you want within it. Adding and processing of any data within that element would depend on your SAML product.

To give you an example of how it's used, here's a spec that leveraged it: http://docs.oasis-open.org/security/saml/SpecDrafts-Post2.0/sstc-saml-protocol-ext-rac.pdf