(Visual FoxPro) Get Certificates within XML Signature

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

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

LOCAL loSbXml
LOCAL lnSuccess
LOCAL loDsig
LOCAL i
LOCAL loSaCerts
LOCAL loCert
LOCAL lnBVerifyReferenceDigests
LOCAL lnBVerified
LOCAL j

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

* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.StringBuilder')
loSbXml = CreateObject('Chilkat.StringBuilder')

* Load XML containing one or more signatures.
lnSuccess = loSbXml.LoadFile("qa_data/xml_dsig_valid_samples/multipleSigners/sp.pdf.XAdES.xml","utf-8")
IF (lnSuccess = 0) THEN
    ? "Failed to load the XML file.."
    RELEASE loSbXml
    CANCEL
ENDIF

* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.XmlDSig')
loDsig = CreateObject('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.
lnSuccess = loDsig.LoadSignatureSb(loSbXml)
IF (lnSuccess <> 1) THEN
    ? loDsig.LastErrorText
    RELEASE loSbXml
    RELEASE loDsig
    CANCEL
ENDIF

* For each signature, verify and also get the certificate(s) contained within each Signature.
i = 0
* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.StringArray')
loSaCerts = CreateObject('Chilkat.StringArray')
* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.Cert')
loCert = CreateObject('Chilkat.Cert')

? "numSignatures = " + STR(loDsig.NumSignatures)

DO WHILE i < loDsig.NumSignatures
    * Select the Nth signature by setting the Selector property.
    loDsig.Selector = i

    lnBVerifyReferenceDigests = 1
    lnBVerified = loDsig.VerifySignature(lnBVerifyReferenceDigests)
    ? "Signature " + STR(i + 1) + " verified = " + STR(lnBVerified)

    * Get the certificates embedded in this signature.
    loSaCerts.Clear()
    lnSuccess = loDsig.GetCerts(loSaCerts)
    IF (lnSuccess = 1) THEN
        j = 0
        DO WHILE j < loSaCerts.Count
            lnSuccess = loCert.LoadFromBase64(loSaCerts.GetString(j))
            IF (lnSuccess = 1) THEN
                ? "    " + loCert.SubjectDN
            ENDIF

            j = j + 1
        ENDDO
    ENDIF

    i = i + 1
ENDDO

RELEASE loSbXml
RELEASE loDsig
RELEASE loSaCerts
RELEASE loCert