<?xml version="1.0" encoding="utf-8"?>
<!-- Schema for XML Signatures
    http://www.w3.org/2000/09/xmldsig#

    Copyright 2001 The Internet Society and W3C (Massachusetts Institute
    of Technology, Institut National de Recherche en Informatique et en
    Automatique, Keio University). All Rights Reserved.
    http://www.w3.org/Consortium/Legal/

    This document is governed by the W3C Software License [1] as described
    in the FAQ [2].

    [1] http://www.w3.org/Consortium/Legal/copyright-software-19980720
    [2] http://www.w3.org/Consortium/Legal/IPR-FAQ-20000620.html#DTD
-->
<schema xmlns="http://www.w3.org/2001/XMLSchema"
        xmlns:ds="http://www.w3.org/2000/09/xmldsig#"
        targetNamespace="http://www.w3.org/2000/09/xmldsig#"
        version="0.1" elementFormDefault="qualified">

    <!-- Basic Types Defined for Signatures -->

    <simpleType name="CryptoBinary">
        <restriction base="base64Binary">
        </restriction>
    </simpleType>

    <!-- Start Signature -->

    <element name="Signature" type="ds:SignatureType"/>
    <complexType name="SignatureType">
        <sequence>
            <element ref="ds:SignedInfo"/>
            <element ref="ds:SignatureValue"/>
            <element ref="ds:KeyInfo" minOccurs="0"/>
            <element ref="ds:Object" minOccurs="0" maxOccurs="unbounded"/>
        </sequence>
        <attribute name="Id" type="ID" use="optional"/>
    </complexType>

    <element name="SignatureValue" type="ds:SignatureValueType"/>
    <complexType name="SignatureValueType">
        <simpleContent>
            <extension base="base64Binary">
                <attribute name="Id" type="ID" use="optional"/>
            </extension>
        </simpleContent>
    </complexType>

    <!-- Start SignedInfo -->

    <element name="SignedInfo" type="ds:SignedInfoType"/>
    <complexType name="SignedInfoType">
        <sequence>
            <element ref="ds:CanonicalizationMethod"/>
            <element ref="ds:SignatureMethod"/>
            <element ref="ds:Reference" maxOccurs="unbounded"/>
        </sequence>
        <attribute name="Id" type="ID" use="optional"/>
    </complexType>

    <element name="CanonicalizationMethod" type="ds:CanonicalizationMethodType"/>
    <complexType name="CanonicalizationMethodType" mixed="true">
        <sequence>
            <any namespace="##any" minOccurs="0" maxOccurs="unbounded"/>
            <!-- (0,unbounded) elements from (1,1) namespace -->
        </sequence>
        <attribute name="Algorithm" type="anyURI" use="required"/>
    </complexType>

    <element name="SignatureMethod" type="ds:SignatureMethodType"/>
    <complexType name="SignatureMethodType" mixed="true">
        <sequence>
            <element name="HMACOutputLength" minOccurs="0" type="ds:HMACOutputLengthType"/>
            <any namespace="##other" minOccurs="0" maxOccurs="unbounded"/>
            <!-- (0,unbounded) elements from (1,1) external namespace -->
        </sequence>
        <attribute name="Algorithm" type="anyURI" use="required"/>
    </complexType>

    <!-- Start Reference -->

    <element name="Reference" type="ds:ReferenceType"/>
    <complexType name="ReferenceType">
        <sequence>
            <element ref="ds:Transforms" minOccurs="0"/>
            <element ref="ds:DigestMethod"/>
            <element ref="ds:DigestValue"/>
        </sequence>
        <attribute name="Id" type="ID" use="optional"/>
        <attribute name="URI" type="anyURI" use="optional"/>
        <attribute name="Type" type="anyURI" use="optional"/>
    </complexType>

    <element name="Transforms" type="ds:TransformsType"/>
    <complexType name="TransformsType">
        <sequence>
            <element ref="ds:Transform" maxOccurs="unbounded"/>
        </sequence>
    </complexType>

    <element name="Transform" type="ds:TransformType"/>
    <complexType name="TransformType" mixed="true">
        <choice minOccurs="0" maxOccurs="unbounded">
            <any namespace="##other" processContents="lax"/>
            <!-- (1,1) elements from (0,unbounded) namespaces -->
            <element name="XPath" type="string"/>
        </choice>
        <attribute name="Algorithm" type="anyURI" use="required"/>
    </complexType>

    <!-- End Reference -->

    <element name="DigestMethod" type="ds:DigestMethodType"/>
    <complexType name="DigestMethodType" mixed="true">
        <sequence>
            <any namespace="##other" processContents="lax" minOccurs="0" maxOccurs="unbounded"/>
        </sequence>
        <attribute name="Algorithm" type="anyURI" use="required"/>
    </complexType>

    <element name="DigestValue" type="ds:DigestValueType"/>
    <simpleType name="DigestValueType">
        <restriction base="base64Binary"/>
    </simpleType>

    <!-- End SignedInfo -->

    <!-- Start KeyInfo -->

    <element name="KeyInfo" type="ds:KeyInfoType"/>
    <complexType name="KeyInfoType" mixed="true">
        <choice maxOccurs="unbounded">
            <element ref="ds:KeyName"/>
            <element ref="ds:KeyValue"/>
            <element ref="ds:RetrievalMethod"/>
            <element ref="ds:X509Data"/>
            <element ref="ds:PGPData"/>
            <element ref="ds:SPKIData"/>
            <element ref="ds:MgmtData"/>
            <any processContents="lax" namespace="##other"/>
            <!-- (1,1) elements from (0,unbounded) namespaces -->
        </choice>
        <attribute name="Id" type="ID" use="optional"/>
    </complexType>

    <element name="KeyName" type="string"/>
    <element name="MgmtData" type="string"/>

    <element name="KeyValue" type="ds:KeyValueType"/>
    <complexType name="KeyValueType" mixed="true">
        <choice>
            <element ref="ds:DSAKeyValue"/>
            <element ref="ds:RSAKeyValue"/>
            <any namespace="##other" processContents="lax"/>
        </choice>
    </complexType>

    <element name="RetrievalMethod" type="ds:RetrievalMethodType"/>
    <complexType name="RetrievalMethodType">
        <sequence>
            <element ref="ds:Transforms" minOccurs="0"/>
        </sequence>
        <attribute name="URI" type="anyURI"/>
        <attribute name="Type" type="anyURI" use="optional"/>
    </complexType>

    <!-- Start X509Data -->

    <element name="X509Data" type="ds:X509DataType"/>
    <complexType name="X509DataType">
        <sequence maxOccurs="unbounded">
            <choice>
                <element name="X509IssuerSerial" type="ds:X509IssuerSerialType"/>
                <element name="X509SKI" type="base64Binary"/>
                <element name="X509SubjectName" type="string"/>
                <element name="X509Certificate" type="base64Binary"/>
                <element name="X509CRL" type="base64Binary"/>
                <any namespace="##other" processContents="lax"/>
            </choice>
        </sequence>
    </complexType>

    <complexType name="X509IssuerSerialType">
        <sequence>
            <element name="X509IssuerName" type="string"/>
            <element name="X509SerialNumber" type="integer"/>
        </sequence>
    </complexType>

    <!-- End X509Data -->

    <!-- Begin PGPData -->

    <element name="PGPData" type="ds:PGPDataType"/>
    <complexType name="PGPDataType">
        <choice>
            <sequence>
                <element name="PGPKeyID" type="base64Binary"/>
                <element name="PGPKeyPacket" type="base64Binary" minOccurs="0"/>
                <any namespace="##other" processContents="lax" minOccurs="0"
                     maxOccurs="unbounded"/>
            </sequence>
            <sequence>
                <element name="PGPKeyPacket" type="base64Binary"/>
                <any namespace="##other" processContents="lax" minOccurs="0"
                     maxOccurs="unbounded"/>
            </sequence>
        </choice>
    </complexType>

    <!-- End PGPData -->

    <!-- Begin SPKIData -->

    <element name="SPKIData" type="ds:SPKIDataType"/>
    <complexType name="SPKIDataType">
        <sequence maxOccurs="unbounded">
            <element name="SPKISexp" type="base64Binary"/>
            <any namespace="##other" processContents="lax" minOccurs="0"/>
        </sequence>
    </complexType>

    <!-- End SPKIData -->

    <!-- End KeyInfo -->

    <!-- Start Object (Manifest, SignatureProperty) -->

    <element name="Object" type="ds:ObjectType"/>
    <complexType name="ObjectType" mixed="true">
        <sequence minOccurs="0" maxOccurs="unbounded">
            <any namespace="##any" processContents="lax"/>
        </sequence>
        <attribute name="Id" type="ID" use="optional"/>
        <attribute name="MimeType" type="string" use="optional"/> <!-- add a grep facet -->
        <attribute name="Encoding" type="anyURI" use="optional"/>
    </complexType>

    <element name="Manifest" type="ds:ManifestType"/>
    <complexType name="ManifestType">
        <sequence>
            <element ref="ds:Reference" maxOccurs="unbounded"/>
        </sequence>
        <attribute name="Id" type="ID" use="optional"/>
    </complexType>

    <element name="SignatureProperties" type="ds:SignaturePropertiesType"/>
    <complexType name="SignaturePropertiesType">
        <sequence>
            <element ref="ds:SignatureProperty" maxOccurs="unbounded"/>
        </sequence>
        <attribute name="Id" type="ID" use="optional"/>
    </complexType>

    <element name="SignatureProperty" type="ds:SignaturePropertyType"/>
    <complexType name="SignaturePropertyType" mixed="true">
        <choice maxOccurs="unbounded">
            <any namespace="##other" processContents="lax"/>
            <!-- (1,1) elements from (1,unbounded) namespaces -->
        </choice>
        <attribute name="Target" type="anyURI" use="required"/>
        <attribute name="Id" type="ID" use="optional"/>
    </complexType>

    <!-- End Object (Manifest, SignatureProperty) -->

    <!-- Start Algorithm Parameters -->

    <simpleType name="HMACOutputLengthType">
        <restriction base="integer"/>
    </simpleType>

    <!-- Start KeyValue Element-types -->

    <element name="DSAKeyValue" type="ds:DSAKeyValueType"/>
    <complexType name="DSAKeyValueType">
        <sequence>
            <sequence minOccurs="0">
                <element name="P" type="ds:CryptoBinary"/>
                <element name="Q" type="ds:CryptoBinary"/>
            </sequence>
            <element name="G" type="ds:CryptoBinary" minOccurs="0"/>
            <element name="Y" type="ds:CryptoBinary"/>
            <element name="J" type="ds:CryptoBinary" minOccurs="0"/>
            <sequence minOccurs="0">
                <element name="Seed" type="ds:CryptoBinary"/>
                <element name="PgenCounter" type="ds:CryptoBinary"/>
            </sequence>
        </sequence>
    </complexType>

    <element name="RSAKeyValue" type="ds:RSAKeyValueType"/>
    <complexType name="RSAKeyValueType">
        <sequence>
            <element name="Modulus" type="ds:CryptoBinary"/>
            <element name="Exponent" type="ds:CryptoBinary"/>
        </sequence>
    </complexType>

    <!-- End KeyValue Element-types -->

    <!-- End Signature -->

</schema>