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Visual Basic 6.0

XML Signature Multiple External References

See more XML Digital Signatures Examples

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

Chilkat Visual Basic 6.0 Downloads

Visual Basic 6.0
Dim success As Long
success = 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
Dim gen As New ChilkatXmlDSigGen

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

' Create an Object to be added to the Signature.
Dim object1 As New ChilkatXml
object1.Tag = "xades:QualifyingProperties"
success = object1.AddAttribute("xmlns:xades","http://uri.etsi.org/01903/v1.3.2#")
success = object1.AddAttribute("xmlns:xades141","http://uri.etsi.org/01903/v1.4.1#")
success = object1.AddAttribute("Target","#xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4")
success = object1.UpdateAttrAt("xades:SignedProperties",1,"Id","xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-signedprops")
object1.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...
success = object1.UpdateAttrAt("xades:SignedProperties|xades:SignedSignatureProperties|xades:SigningCertificateV2|xades:Cert|xades:CertDigest|ds:DigestMethod",1,"Algorithm","http://www.w3.org/2001/04/xmlenc#sha256")
object1.UpdateChildContent "xades:SignedProperties|xades:SignedSignatureProperties|xades:SigningCertificateV2|xades:Cert|xades:CertDigest|ds:DigestValue","TO BE GENERATED BY CHILKAT"
object1.UpdateChildContent "xades:SignedProperties|xades:SignedSignatureProperties|xades:SigningCertificateV2|xades:Cert|xades:IssuerSerialV2","TO BE GENERATED BY CHILKAT"

success = gen.AddObject("",object1.GetXml(),"","")

Dim http As New ChilkatHttp
Dim bd As New ChilkatBinData

Dim url As String
url = "https://isus.ezdrowie.gov.pl/fhir/Patient/123/_history/456"
success = http.QuickGetBd(url,bd)
If (success <> 1) Then
    Debug.Print http.LastErrorText
    Exit Sub
End If

' -------- Reference 1 --------
success = gen.AddExternalBinaryRef(url,bd,"sha256","")
success = gen.SetRefIdAttr(url,"xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref0")

' -------- Reference 2 --------
success = bd.Clear()
url = "https://isus.ezdrowie.gov.pl/fhir/Encounter/789/_history/1"
success = http.QuickGetBd(url,bd)
If (success <> 1) Then
    Debug.Print http.LastErrorText
    Exit Sub
End If

success = gen.AddExternalBinaryRef(url,bd,"sha256","")
success = gen.SetRefIdAttr(url,"xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref1")

' -------- Reference 3 --------
success = bd.Clear()
url = "https://isus.ezdrowie.gov.pl/fhir/Condition/123456/_history/1"
success = http.QuickGetBd(url,bd)
If (success <> 1) Then
    Debug.Print http.LastErrorText
    Exit Sub
End If

success = gen.AddExternalBinaryRef(url,bd,"sha256","")
success = gen.SetRefIdAttr(url,"xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref2")

' -------- Reference 4 --------
success = bd.Clear()
url = "https://isus.ezdrowie.gov.pl/fhir/Procedure/123456/_history/1"
success = http.QuickGetBd(url,bd)
If (success <> 1) Then
    Debug.Print http.LastErrorText
    Exit Sub
End If

success = gen.AddExternalBinaryRef(url,bd,"sha256","")
success = gen.SetRefIdAttr(url,"xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref3")

' -------- Reference 5 --------
success = gen.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)
Dim cert As New ChilkatCert
success = cert.LoadPfxFile("qa_data/pfx/cert_test123.pfx","test123")
If (success <> 1) Then
    Debug.Print cert.LastErrorText
    Exit Sub
End If

success = gen.SetX509Cert(cert,1)

gen.KeyInfoType = "X509Data"
gen.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.
Dim sbXml As New ChilkatStringBuilder

gen.Behaviors = "IndentedSignature"

' Sign the XML...
success = gen.CreateXmlDSigSb(sbXml)
If (success <> 1) Then
    Debug.Print gen.LastErrorText
    Exit Sub
End If

' -----------------------------------------------

' Save the signed XML to a file.
success = sbXml.WriteFile("qa_output/signedXml.xml","utf-8",0)

Debug.Print sbXml.GetAsString()

' ----------------------------------------
' Verify the signature we just produced...
Dim verifier As New ChilkatXmlDSig
success = verifier.LoadSignatureSb(sbXml)
If (success <> 1) Then
    Debug.Print verifier.LastErrorText
    Exit Sub
End If

Dim verified As Long
verified = verifier.VerifySignature(1)
If (verified <> 1) Then
    Debug.Print verifier.LastErrorText
    Exit Sub
End If

Debug.Print "This signature was successfully verified."