(Xojo Plugin) Get Certificates within XML Signature

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

Chilkat Xojo Plugin Download Xojo Plugin for Windows, Linux, Mac OS X, and ARM, ARM64

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

Dim sbXml As New Chilkat.StringBuilder

// Load XML containing one or more signatures.
Dim success As Boolean
success = sbXml.LoadFile("qa_data/xml_dsig_valid_samples/multipleSigners/sp.pdf.XAdES.xml","utf-8")
If (success = False) Then
    System.DebugLog("Failed to load the XML file..")
    Return
End If

Dim dsig As New Chilkat.XmlDSig

// 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
    System.DebugLog(dsig.LastErrorText)
    Return
End If

// For each signature, verify and also get the certificate(s) contained within each Signature.
Dim i As Int32
i = 0
Dim saCerts As New Chilkat.StringArray
Dim cert As New Chilkat.Cert

System.DebugLog("numSignatures = " + Str(dsig.NumSignatures))

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

    Dim bVerifyReferenceDigests As Boolean
    bVerifyReferenceDigests = True
    Dim bVerified As Boolean
    bVerified = dsig.VerifySignature(bVerifyReferenceDigests)
    System.DebugLog("Signature " + Str(i + 1) + " verified = " + Str(bVerified))

    // Get the certificates embedded in this signature.
    saCerts.Clear 
    success = dsig.GetCerts(saCerts)
    If (success = True) Then
        Dim j As Int32
        j = 0
        While j < saCerts.Count
            success = cert.LoadFromBase64(saCerts.GetString(j))
            If (success = True) Then
                System.DebugLog("    " + cert.SubjectDN)
            End If

            j = j + 1
        Wend
    End If

    i = i + 1
Wend