(Excel) Get Certificates within XML Signature

Demonstrates how to get the certificates contained within an XML signature.

Download Excel Class Modules Chilkat Excel Class Modules

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

Dim sbXml As Chilkat.StringBuilder
Set sbXml = Chilkat.NewStringBuilder

' Load XML containing one or more signatures.

success = sbXml.LoadFile("qa_data/xml_dsig_valid_samples/multipleSigners/sp.pdf.XAdES.xml","utf-8")
If (success = False) Then
    Debug.Print "Failed to load the XML file.."
    Exit Sub
End If

Dim dsig As Chilkat.XmlDSig
Set dsig = Chilkat.NewXmlDSig

' First load the XML containing the signatures to be verified.
' Note that this particular Signature already contains the RSA public key that will be used
' for verification.
success = dsig.LoadSignatureSb(sbXml)
If (success <> True) Then
    Debug.Print dsig.LastErrorText
    Exit Sub
End If

' For each signature, verify and also get the certificate(s) contained within each Signature.

i = 0
Dim saCerts As Chilkat.StringArray
Set saCerts = Chilkat.NewStringArray
Dim cert As Chilkat.Cert
Set cert = Chilkat.NewCert

Debug.Print "numSignatures = "; dsig.NumSignatures

Do While i < dsig.NumSignatures
    ' Select the Nth signature by setting the Selector property.
    dsig.Selector = i


    bVerifyReferenceDigests = True

    bVerified = dsig.VerifySignature(bVerifyReferenceDigests)
    Debug.Print "Signature "; (i + 1); " verified = "; bVerified

    ' Get the certificates embedded in this signature.
    saCerts.Clear 
    success = dsig.GetCerts(saCerts)
    If (success = True) Then

        j = 0
        Do While j < saCerts.Count
            success = cert.LoadFromBase64(saCerts.GetString(j))
            If (success = True) Then
                Debug.Print "    "; cert.SubjectDN
            End If

            j = j + 1
        Loop
    End If

    i = i + 1
Loop