<?xml version="1.0" encoding="UTF-8"?>

<xs:schema targetNamespace="urn:oasis:names:tc:SAML:2.0:ac:classes:TimeSyncToken"
  xmlns:ac="urn:oasis:names:tc:SAML:2.0:ac" 
  xmlns:xs="http://www.w3.org/2001/XMLSchema" 
  xmlns="urn:oasis:names:tc:SAML:2.0:ac:classes:TimeSyncToken"
  finalDefault="extension">

  <xs:import namespace="urn:oasis:names:tc:SAML:2.0:ac" schemaLocation="sstc-saml-schema-authn-context-1.0.xsd"/>

  <xs:annotation>
    <xs:documentation> 
      urn:oasis:names:tc:SAML:2.0:ac:classes:TimeSyncToken
    </xs:documentation>
  </xs:annotation>

  <xs:complexType name="AuthnContextDeclaration">
    <xs:complexContent>
      <xs:restriction base="ac:AuthnContextDeclarationBaseType">
        <xs:sequence>
          <xs:element ref="ac:Identification" minOccurs="0"/>
          <xs:element ref="ac:TechnicalProtection" minOccurs="0"/>
          <xs:element ref="ac:OperationalProtection" minOccurs="0"/>
          <xs:element ref="AuthnMethod"/>
          <xs:element ref="ac:GoverningAgreements" minOccurs="0"/>
          <xs:element ref="ac:AuthenticatingAuthority" minOccurs="0"
            maxOccurs="unbounded"/>
          <xs:element ref="ac:Extension" minOccurs="0"
            maxOccurs="unbounded"/>
        </xs:sequence>
        <xs:attribute name="ID" type="xs:ID"/>
      </xs:restriction>
    </xs:complexContent>
  </xs:complexType>

  <xs:element name="AuthnMethod" type="AuthnMethodType"/>

  <xs:complexType name="AuthnMethodType">
    <xs:complexContent>
      <xs:restriction base="ac:AuthnMethodBaseType">
        <xs:sequence>
          <xs:element ref="PrincipalAuthenticationMechanism" minOccurs="0"/>
          <xs:element ref="ac:Authenticator"/>
          <xs:element ref="ac:AuthenticatorTransportProtocol"
            minOccurs="0"/>
          <xs:element ref="ac:Extension" minOccurs="0"
            maxOccurs="unbounded"/>
        </xs:sequence>
      </xs:restriction>
    </xs:complexContent>
  </xs:complexType>

  <xs:element name="PrincipalAuthenticationMechanism" type="TimeSyncMechType"/>

  <xs:complexType name="TimeSyncMechType">
    <xs:complexContent>
      <xs:restriction base="ac:PrincipalAuthenticationMechanismType">
        <xs:choice>
          <xs:element ref="Token"/>
        </xs:choice>
      </xs:restriction>
    </xs:complexContent>
  </xs:complexType>

  <xs:element name="Token" type="TokenType"/>

  <xs:complexType name="TokenType">
    <xs:complexContent>
      <xs:restriction base="ac:TokenType">
        <xs:sequence>
          <xs:element ref="TimeSyncToken"/>
          <xs:element ref="ac:Extension" minOccurs="0" maxOccurs="unbounded"/>
        </xs:sequence>
      </xs:restriction>
    </xs:complexContent>
  </xs:complexType>

  <xs:element name="TimeSyncToken" type="TimeSyncTokenType"/>

  <xs:complexType name="TimeSyncTokenType">
    <xs:complexContent>
      <xs:restriction base="ac:TimeSyncTokenType">

        <xs:attribute name="DeviceType" use="required">
          <xs:simpleType>
            <xs:restriction base="xs:NMTOKEN">
              <xs:enumeration value="hardware"/>
            </xs:restriction>
          </xs:simpleType>
        </xs:attribute>

        <xs:attribute name="SeedLength" use="required">
          <xs:simpleType>
            <xs:restriction base="xs:integer">
              <xs:minInclusive value="64"/>
            </xs:restriction>
          </xs:simpleType>
        </xs:attribute>

        <xs:attribute name="DeviceInHand" use="required">
          <xs:simpleType>
            <xs:restriction base="xs:NMTOKEN">
              <xs:enumeration value="true"/>
            </xs:restriction>
          </xs:simpleType>
        </xs:attribute>
      </xs:restriction>
    </xs:complexContent>
  </xs:complexType>

</xs:schema>