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PureBasic

XML Signature Multiple External References

See more XML Digital Signatures Examples

Demonstrates how to add multiple external references to an XML digital signature.

Chilkat PureBasic Downloads

PureBasic
IncludeFile "CkBinData.pb"
IncludeFile "CkHttp.pb"
IncludeFile "CkXmlDSigGen.pb"
IncludeFile "CkXmlDSig.pb"
IncludeFile "CkXml.pb"
IncludeFile "CkCert.pb"
IncludeFile "CkStringBuilder.pb"

Procedure ChilkatExample()

    success.i = 0

    ; This example requires the Chilkat API to have been previously unlocked.
    ; See Global Unlock Sample for sample code.

    ; This example creates the following signed XML with multiple external references:

    ; <?xml version="1.0" encoding="UTF-8"?>
    ; <ds:Signature xmlns:ds="http://www.w3.org/2000/09/xmldsig#" Id="xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4">
    ;     <ds:SignedInfo>
    ;         <ds:CanonicalizationMethod Algorithm="http://www.w3.org/TR/2001/REC-xml-c14n-20010315"/>
    ;         <ds:SignatureMethod Algorithm="http://www.w3.org/2001/04/xmldsig-more#rsa-sha256"/>
    ;         <ds:Reference Id="xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref0" URI="https://isus.ezdrowie.gov.pl/fhir/Patient/123/_history/456">
    ;             <ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/>
    ;             <ds:DigestValue>...</ds:DigestValue>
    ;         </ds:Reference>
    ;         <ds:Reference Id="xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref1" URI="https://isus.ezdrowie.gov.pl/fhir/Encounter/124/_history/22">
    ;             <ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/>
    ;             <ds:DigestValue>...</ds:DigestValue>
    ;         </ds:Reference>
    ;         <ds:Reference Id="xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref2" URI="https://isus.ezdrowie.gov.pl/fhir/Condition/125/_history/1">
    ;             <ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/>
    ;             <ds:DigestValue>...</ds:DigestValue>
    ;         </ds:Reference>
    ;         <ds:Reference Id="xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref3" URI="https://isus.ezdrowie.gov.pl/fhir/Procedure/126/_history/1">
    ;             <ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/>
    ;             <ds:DigestValue>...</ds:DigestValue>
    ;         </ds:Reference>
    ;         <ds:Reference Type="http://uri.etsi.org/01903#SignedProperties" URI="#xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-signedprops">
    ;             <ds:Transforms>
    ;                 <ds:Transform Algorithm="http://www.w3.org/TR/2001/REC-xml-c14n-20010315"/>
    ;             </ds:Transforms>
    ;             <ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/>
    ;             <ds:DigestValue>...</ds:DigestValue>
    ;         </ds:Reference>
    ;     </ds:SignedInfo>
    ;     <ds:SignatureValue Id="xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-sigvalue">...</ds:SignatureValue>
    ;     <ds:KeyInfo>
    ;         <ds:X509Data>
    ;             <ds:X509Certificate>...</ds:X509Certificate>
    ;             <ds:X509SubjectName>...</ds:X509SubjectName>
    ;             <ds:X509IssuerSerial>
    ;                 <ds:X509IssuerName>...</ds:X509IssuerName>
    ;                 <ds:X509SerialNumber>...</ds:X509SerialNumber>
    ;             </ds:X509IssuerSerial>
    ;         </ds:X509Data>
    ;     </ds:KeyInfo>
    ;     <ds:Object>
    ;         <xades:QualifyingProperties xmlns:xades="http://uri.etsi.org/01903/v1.3.2#" xmlns:xades141="http://uri.etsi.org/01903/v1.4.1#" Target="#xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4">
    ;             <xades:SignedProperties Id="xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-signedprops">
    ;                 <xades:SignedSignatureProperties>
    ;                     <xades:SigningTime>2021-06-02T07:10:13.306+02:00</xades:SigningTime>
    ;                     <xades:SigningCertificate>
    ;                         <xades:Cert>
    ;                             <xades:CertDigest>
    ;                                 <ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/>
    ;                                 <ds:DigestValue>...</ds:DigestValue>
    ;                             </xades:CertDigest>
    ;                             <xades:IssuerSerial>
    ;                                 <ds:X509IssuerName>...</ds:X509IssuerName>
    ;                                 <ds:X509SerialNumber>...</ds:X509SerialNumber>
    ;                             </xades:IssuerSerial>
    ;                         </xades:Cert>
    ;                         <xades:Cert>
    ;                             <xades:CertDigest>
    ;                                 <ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/>
    ;                                 <ds:DigestValue>...</ds:DigestValue>
    ;                             </xades:CertDigest>
    ;                             <xades:IssuerSerial>
    ;                                 <ds:X509IssuerName>...</ds:X509IssuerName>
    ;                                 <ds:X509SerialNumber>...</ds:X509SerialNumber>
    ;                             </xades:IssuerSerial>
    ;                         </xades:Cert>
    ;                         <xades:Cert>
    ;                             <xades:CertDigest>
    ;                                 <ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/>
    ;                                 <ds:DigestValue>...</ds:DigestValue>
    ;                             </xades:CertDigest>
    ;                             <xades:IssuerSerial>
    ;                                 <ds:X509IssuerName>...</ds:X509IssuerName>
    ;                                 <ds:X509SerialNumber>...</ds:X509SerialNumber>
    ;                             </xades:IssuerSerial>
    ;                         </xades:Cert>
    ;                     </xades:SigningCertificate>
    ;                 </xades:SignedSignatureProperties>
    ;             </xades:SignedProperties>
    ;         </xades:QualifyingProperties>
    ;     </ds:Object>
    ; </ds:Signature>
    ; 

    success = 1
    gen.i = CkXmlDSigGen::ckCreate()
    If gen.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkXmlDSigGen::setCkSigLocation(gen, "")
    CkXmlDSigGen::setCkSigLocationMod(gen, 0)
    ; Note: ID's simply need to be unique values in the signed XML document.  They don't necessarily need to be GUID/UUID formatted.
    CkXmlDSigGen::setCkSigId(gen, "xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4")
    CkXmlDSigGen::setCkSigNamespacePrefix(gen, "ds")
    CkXmlDSigGen::setCkSigNamespaceUri(gen, "http://www.w3.org/2000/09/xmldsig#")
    CkXmlDSigGen::setCkSigValueId(gen, "xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-sigvalue")
    CkXmlDSigGen::setCkSignedInfoCanonAlg(gen, "C14N")
    CkXmlDSigGen::setCkSignedInfoDigestMethod(gen, "sha256")

    ; Create an Object to be added to the Signature.
    object1.i = CkXml::ckCreate()
    If object1.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkXml::setCkTag(object1, "xades:QualifyingProperties")
    CkXml::ckAddAttribute(object1,"xmlns:xades","http://uri.etsi.org/01903/v1.3.2#")
    CkXml::ckAddAttribute(object1,"xmlns:xades141","http://uri.etsi.org/01903/v1.4.1#")
    CkXml::ckAddAttribute(object1,"Target","#xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4")
    CkXml::ckUpdateAttrAt(object1,"xades:SignedProperties",1,"Id","xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-signedprops")
    CkXml::ckUpdateChildContent(object1,"xades:SignedProperties|xades:SignedSignatureProperties|xades:SigningTime","TO BE GENERATED BY CHILKAT")
    ; This assumes there are 3 certs in the certificate chain:  The signing certificate, an intermediate root, and the root CA.
    ; Remove the lines with "Cert[2]" if there is no intermediate root...
    CkXml::ckUpdateAttrAt(object1,"xades:SignedProperties|xades:SignedSignatureProperties|xades:SigningCertificateV2|xades:Cert|xades:CertDigest|ds:DigestMethod",1,"Algorithm","http://www.w3.org/2001/04/xmlenc#sha256")
    CkXml::ckUpdateChildContent(object1,"xades:SignedProperties|xades:SignedSignatureProperties|xades:SigningCertificateV2|xades:Cert|xades:CertDigest|ds:DigestValue","TO BE GENERATED BY CHILKAT")
    CkXml::ckUpdateChildContent(object1,"xades:SignedProperties|xades:SignedSignatureProperties|xades:SigningCertificateV2|xades:Cert|xades:IssuerSerialV2","TO BE GENERATED BY CHILKAT")

    CkXmlDSigGen::ckAddObject(gen,"",CkXml::ckGetXml(object1),"","")

    http.i = CkHttp::ckCreate()
    If http.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    bd.i = CkBinData::ckCreate()
    If bd.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    url.s = "https://isus.ezdrowie.gov.pl/fhir/Patient/123/_history/456"
    success = CkHttp::ckQuickGetBd(http,url,bd)
    If success <> 1
        Debug CkHttp::ckLastErrorText(http)
        CkXmlDSigGen::ckDispose(gen)
        CkXml::ckDispose(object1)
        CkHttp::ckDispose(http)
        CkBinData::ckDispose(bd)
        ProcedureReturn
    EndIf

    ; -------- Reference 1 --------
    CkXmlDSigGen::ckAddExternalBinaryRef(gen,url,bd,"sha256","")
    CkXmlDSigGen::ckSetRefIdAttr(gen,url,"xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref0")

    ; -------- Reference 2 --------
    CkBinData::ckClear(bd)
    url = "https://isus.ezdrowie.gov.pl/fhir/Encounter/789/_history/1"
    success = CkHttp::ckQuickGetBd(http,url,bd)
    If success <> 1
        Debug CkHttp::ckLastErrorText(http)
        CkXmlDSigGen::ckDispose(gen)
        CkXml::ckDispose(object1)
        CkHttp::ckDispose(http)
        CkBinData::ckDispose(bd)
        ProcedureReturn
    EndIf

    CkXmlDSigGen::ckAddExternalBinaryRef(gen,url,bd,"sha256","")
    CkXmlDSigGen::ckSetRefIdAttr(gen,url,"xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref1")

    ; -------- Reference 3 --------
    CkBinData::ckClear(bd)
    url = "https://isus.ezdrowie.gov.pl/fhir/Condition/123456/_history/1"
    success = CkHttp::ckQuickGetBd(http,url,bd)
    If success <> 1
        Debug CkHttp::ckLastErrorText(http)
        CkXmlDSigGen::ckDispose(gen)
        CkXml::ckDispose(object1)
        CkHttp::ckDispose(http)
        CkBinData::ckDispose(bd)
        ProcedureReturn
    EndIf

    CkXmlDSigGen::ckAddExternalBinaryRef(gen,url,bd,"sha256","")
    CkXmlDSigGen::ckSetRefIdAttr(gen,url,"xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref2")

    ; -------- Reference 4 --------
    CkBinData::ckClear(bd)
    url = "https://isus.ezdrowie.gov.pl/fhir/Procedure/123456/_history/1"
    success = CkHttp::ckQuickGetBd(http,url,bd)
    If success <> 1
        Debug CkHttp::ckLastErrorText(http)
        CkXmlDSigGen::ckDispose(gen)
        CkXml::ckDispose(object1)
        CkHttp::ckDispose(http)
        CkBinData::ckDispose(bd)
        ProcedureReturn
    EndIf

    CkXmlDSigGen::ckAddExternalBinaryRef(gen,url,bd,"sha256","")
    CkXmlDSigGen::ckSetRefIdAttr(gen,url,"xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref3")

    ; -------- Reference 5 --------
    CkXmlDSigGen::ckAddObjectRef(gen,"xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-signedprops","sha256","C14N","","http://uri.etsi.org/01903#SignedProperties")

    ; Provide a certificate + private key. (PFX password is test123)
    cert.i = CkCert::ckCreate()
    If cert.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    success = CkCert::ckLoadPfxFile(cert,"qa_data/pfx/cert_test123.pfx","test123")
    If success <> 1
        Debug CkCert::ckLastErrorText(cert)
        CkXmlDSigGen::ckDispose(gen)
        CkXml::ckDispose(object1)
        CkHttp::ckDispose(http)
        CkBinData::ckDispose(bd)
        CkCert::ckDispose(cert)
        ProcedureReturn
    EndIf

    CkXmlDSigGen::ckSetX509Cert(gen,cert,1)

    CkXmlDSigGen::setCkKeyInfoType(gen, "X509Data")
    CkXmlDSigGen::setCkX509Type(gen, "IssuerSerial,SubjectName,Certificate")

    ; This will be an enveloping signature where the Signature element
    ; is the XML document root, the signed data is contained within Object
    ; tag(s) within the Signature.
    ; Therefore, pass an empty sbXml to CreateXmlDsigSb.
    sbXml.i = CkStringBuilder::ckCreate()
    If sbXml.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkXmlDSigGen::setCkBehaviors(gen, "IndentedSignature")

    ; Sign the XML...
    success = CkXmlDSigGen::ckCreateXmlDSigSb(gen,sbXml)
    If success <> 1
        Debug CkXmlDSigGen::ckLastErrorText(gen)
        CkXmlDSigGen::ckDispose(gen)
        CkXml::ckDispose(object1)
        CkHttp::ckDispose(http)
        CkBinData::ckDispose(bd)
        CkCert::ckDispose(cert)
        CkStringBuilder::ckDispose(sbXml)
        ProcedureReturn
    EndIf

    ; -----------------------------------------------

    ; Save the signed XML to a file.
    success = CkStringBuilder::ckWriteFile(sbXml,"qa_output/signedXml.xml","utf-8",0)

    Debug CkStringBuilder::ckGetAsString(sbXml)

    ; ----------------------------------------
    ; Verify the signature we just produced...
    verifier.i = CkXmlDSig::ckCreate()
    If verifier.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    success = CkXmlDSig::ckLoadSignatureSb(verifier,sbXml)
    If success <> 1
        Debug CkXmlDSig::ckLastErrorText(verifier)
        CkXmlDSigGen::ckDispose(gen)
        CkXml::ckDispose(object1)
        CkHttp::ckDispose(http)
        CkBinData::ckDispose(bd)
        CkCert::ckDispose(cert)
        CkStringBuilder::ckDispose(sbXml)
        CkXmlDSig::ckDispose(verifier)
        ProcedureReturn
    EndIf

    verified.i = CkXmlDSig::ckVerifySignature(verifier,1)
    If verified <> 1
        Debug CkXmlDSig::ckLastErrorText(verifier)
        CkXmlDSigGen::ckDispose(gen)
        CkXml::ckDispose(object1)
        CkHttp::ckDispose(http)
        CkBinData::ckDispose(bd)
        CkCert::ckDispose(cert)
        CkStringBuilder::ckDispose(sbXml)
        CkXmlDSig::ckDispose(verifier)
        ProcedureReturn
    EndIf

    Debug "This signature was successfully verified."


    CkXmlDSigGen::ckDispose(gen)
    CkXml::ckDispose(object1)
    CkHttp::ckDispose(http)
    CkBinData::ckDispose(bd)
    CkCert::ckDispose(cert)
    CkStringBuilder::ckDispose(sbXml)
    CkXmlDSig::ckDispose(verifier)


    ProcedureReturn
EndProcedure