Visual Basic 6.0

Get Certificates within XML Signature

See more XML Digital Signatures Examples

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

Dim sbXml As New ChilkatStringBuilder

' 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 = 0) Then
    Debug.Print "Failed to load the XML file.."
    Exit Sub
End If

Dim dsig As New ChilkatXmlDSig

' 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 <> 1) Then
    Debug.Print dsig.LastErrorText
    Exit Sub
End If

' For each signature, verify and also get the certificate(s) contained within each Signature.
Dim i As Long
i = 0
Dim saCerts As New CkStringArray
Dim cert As New ChilkatCert

Debug.Print "numSignatures = " & dsig.NumSignatures

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

    Dim bVerifyReferenceDigests As Long
    bVerifyReferenceDigests = 1
    Dim bVerified As Long
    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 = 1) Then
        Dim j As Long
        j = 0
        Do While j < saCerts.Count
            success = cert.LoadFromBase64(saCerts.GetString(j))
            If (success = 1) Then
                Debug.Print "    " & cert.SubjectDN
            End If

            j = j + 1
        Loop
    End If

    i = i + 1
Loop