(Visual FoxPro) Verify XML Digital Signature

Verifies XML signatures in an XML file.

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

LOCAL loSbXml
LOCAL lnSuccess
LOCAL loDsig
LOCAL i
LOCAL lnBVerifyReferenceDigests
LOCAL lnBVerified

* 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')
lnSuccess = loSbXml.LoadFile("qa_data/xml_dsig_verify/csioz_sample.xml","utf-8")
IF (lnSuccess <> 1) THEN
    ? "Failed to load 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.
lnSuccess = loDsig.LoadSignatureSb(loSbXml)
IF (lnSuccess <> 1) THEN
    ? loDsig.LastErrorText
    RELEASE loSbXml
    RELEASE loDsig
    CANCEL
ENDIF

* It's possible that an XML document can contain multiple signatures.
* Each can be verified as follows:
i = 0
DO WHILE i < loDsig.NumSignatures
    * Select the Nth signature by setting the Selector property.
    loDsig.Selector = i

    * The bVerifyReferenceDigests argument determines if we want
    * to also verify each reference digest.  If set to 0,
    * then only the SignedInfo part of the Signature is verified.
    lnBVerifyReferenceDigests = 1
    lnBVerified = loDsig.VerifySignature(lnBVerifyReferenceDigests)
    ? "Signature " + STR(i + 1) + " verified = " + STR(lnBVerified)

    i = i + 1
ENDDO

RELEASE loSbXml
RELEASE loDsig