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Visual FoxPro

XML Signature Multiple External References

See more XML Digital Signatures Examples

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

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LOCAL lnSuccess
LOCAL loGen
LOCAL loObject1
LOCAL loHttp
LOCAL loBd
LOCAL lcUrl
LOCAL loCert
LOCAL loSbXml
LOCAL loVerifier
LOCAL lnVerified

lnSuccess = 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>
* 

lnSuccess = 1
loGen = CreateObject('Chilkat.XmlDSigGen')

loGen.SigLocation = ""
loGen.SigLocationMod = 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.
loGen.SigId = "xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4"
loGen.SigNamespacePrefix = "ds"
loGen.SigNamespaceUri = "http://www.w3.org/2000/09/xmldsig#"
loGen.SigValueId = "xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-sigvalue"
loGen.SignedInfoCanonAlg = "C14N"
loGen.SignedInfoDigestMethod = "sha256"

* Create an Object to be added to the Signature.
loObject1 = CreateObject('Chilkat.Xml')
loObject1.Tag = "xades:QualifyingProperties"
loObject1.AddAttribute("xmlns:xades","http://uri.etsi.org/01903/v1.3.2#")
loObject1.AddAttribute("xmlns:xades141","http://uri.etsi.org/01903/v1.4.1#")
loObject1.AddAttribute("Target","#xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4")
loObject1.UpdateAttrAt("xades:SignedProperties",1,"Id","xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-signedprops")
loObject1.UpdateChildContent("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...
loObject1.UpdateAttrAt("xades:SignedProperties|xades:SignedSignatureProperties|xades:SigningCertificateV2|xades:Cert|xades:CertDigest|ds:DigestMethod",1,"Algorithm","http://www.w3.org/2001/04/xmlenc#sha256")
loObject1.UpdateChildContent("xades:SignedProperties|xades:SignedSignatureProperties|xades:SigningCertificateV2|xades:Cert|xades:CertDigest|ds:DigestValue","TO BE GENERATED BY CHILKAT")
loObject1.UpdateChildContent("xades:SignedProperties|xades:SignedSignatureProperties|xades:SigningCertificateV2|xades:Cert|xades:IssuerSerialV2","TO BE GENERATED BY CHILKAT")

loGen.AddObject("",loObject1.GetXml(),"","")

loHttp = CreateObject('Chilkat.Http')
loBd = CreateObject('Chilkat.BinData')

lcUrl = "https://isus.ezdrowie.gov.pl/fhir/Patient/123/_history/456"
lnSuccess = loHttp.QuickGetBd(lcUrl,loBd)
IF (lnSuccess <> 1) THEN
    ? loHttp.LastErrorText
    RELEASE loGen
    RELEASE loObject1
    RELEASE loHttp
    RELEASE loBd
    CANCEL
ENDIF

* -------- Reference 1 --------
loGen.AddExternalBinaryRef(lcUrl,loBd,"sha256","")
loGen.SetRefIdAttr(lcUrl,"xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref0")

* -------- Reference 2 --------
loBd.Clear()
lcUrl = "https://isus.ezdrowie.gov.pl/fhir/Encounter/789/_history/1"
lnSuccess = loHttp.QuickGetBd(lcUrl,loBd)
IF (lnSuccess <> 1) THEN
    ? loHttp.LastErrorText
    RELEASE loGen
    RELEASE loObject1
    RELEASE loHttp
    RELEASE loBd
    CANCEL
ENDIF

loGen.AddExternalBinaryRef(lcUrl,loBd,"sha256","")
loGen.SetRefIdAttr(lcUrl,"xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref1")

* -------- Reference 3 --------
loBd.Clear()
lcUrl = "https://isus.ezdrowie.gov.pl/fhir/Condition/123456/_history/1"
lnSuccess = loHttp.QuickGetBd(lcUrl,loBd)
IF (lnSuccess <> 1) THEN
    ? loHttp.LastErrorText
    RELEASE loGen
    RELEASE loObject1
    RELEASE loHttp
    RELEASE loBd
    CANCEL
ENDIF

loGen.AddExternalBinaryRef(lcUrl,loBd,"sha256","")
loGen.SetRefIdAttr(lcUrl,"xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref2")

* -------- Reference 4 --------
loBd.Clear()
lcUrl = "https://isus.ezdrowie.gov.pl/fhir/Procedure/123456/_history/1"
lnSuccess = loHttp.QuickGetBd(lcUrl,loBd)
IF (lnSuccess <> 1) THEN
    ? loHttp.LastErrorText
    RELEASE loGen
    RELEASE loObject1
    RELEASE loHttp
    RELEASE loBd
    CANCEL
ENDIF

loGen.AddExternalBinaryRef(lcUrl,loBd,"sha256","")
loGen.SetRefIdAttr(lcUrl,"xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref3")

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

* Provide a certificate + private key. (PFX password is test123)
loCert = CreateObject('Chilkat.Cert')
lnSuccess = loCert.LoadPfxFile("qa_data/pfx/cert_test123.pfx","test123")
IF (lnSuccess <> 1) THEN
    ? loCert.LastErrorText
    RELEASE loGen
    RELEASE loObject1
    RELEASE loHttp
    RELEASE loBd
    RELEASE loCert
    CANCEL
ENDIF

loGen.SetX509Cert(loCert,1)

loGen.KeyInfoType = "X509Data"
loGen.X509Type = "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.
loSbXml = CreateObject('Chilkat.StringBuilder')

loGen.Behaviors = "IndentedSignature"

* Sign the XML...
lnSuccess = loGen.CreateXmlDSigSb(loSbXml)
IF (lnSuccess <> 1) THEN
    ? loGen.LastErrorText
    RELEASE loGen
    RELEASE loObject1
    RELEASE loHttp
    RELEASE loBd
    RELEASE loCert
    RELEASE loSbXml
    CANCEL
ENDIF

* -----------------------------------------------

* Save the signed XML to a file.
lnSuccess = loSbXml.WriteFile("qa_output/signedXml.xml","utf-8",0)

? loSbXml.GetAsString()

* ----------------------------------------
* Verify the signature we just produced...
loVerifier = CreateObject('Chilkat.XmlDSig')
lnSuccess = loVerifier.LoadSignatureSb(loSbXml)
IF (lnSuccess <> 1) THEN
    ? loVerifier.LastErrorText
    RELEASE loGen
    RELEASE loObject1
    RELEASE loHttp
    RELEASE loBd
    RELEASE loCert
    RELEASE loSbXml
    RELEASE loVerifier
    CANCEL
ENDIF

lnVerified = loVerifier.VerifySignature(1)
IF (lnVerified <> 1) THEN
    ? loVerifier.LastErrorText
    RELEASE loGen
    RELEASE loObject1
    RELEASE loHttp
    RELEASE loBd
    RELEASE loCert
    RELEASE loSbXml
    RELEASE loVerifier
    CANCEL
ENDIF

? "This signature was successfully verified."

RELEASE loGen
RELEASE loObject1
RELEASE loHttp
RELEASE loBd
RELEASE loCert
RELEASE loSbXml
RELEASE loVerifier