(Visual FoxPro) Add EncapsulatedTimestamp to Already-Signed XML

See more XML Digital Signatures Examples

Demonstrates how to add an EncapsulatedTimestamp to an existing XML signature.

Note: This example requires Chilkat v9.5.0.90 or greater.

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

LOCAL loSbXml
LOCAL lnSuccess
LOCAL loDsig
LOCAL loJson
LOCAL loSbOut
LOCAL loVerifier
LOCAL lnNumSigs
LOCAL lnVerifyIdx
LOCAL lnVerified

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

* Note: We cannot load the already-signed XML into a Chilkat XML object because it would re-format the XML when re-emitted.
* (i.e. indentation and whitespace could change, and it would invalidate the existing signature.)
* We must use a StringBuilder.
* 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_valid_samples/encapsulatedTimestamp_not_yet_added.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')
lnSuccess = loDsig.LoadSignatureSb(loSbXml)
IF (lnSuccess = 0) THEN
    ? loDsig.LastErrorText
    RELEASE loSbXml
    RELEASE loDsig
    CANCEL
ENDIF

IF (loDsig.HasEncapsulatedTimeStamp() = 1) THEN
    ? "This signed XML already has an EncapsulatedTimeStamp"
    RELEASE loSbXml
    RELEASE loDsig
    CANCEL
ENDIF

* Specify the timestamping authority URL
* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.JsonObject')
loJson = CreateObject('Chilkat.JsonObject')
loJson.UpdateString("timestampToken.tsaUrl","http://timestamp.digicert.com")
loJson.UpdateBool("timestampToken.requestTsaCert",1)

* Call AddEncapsulatedTimeStamp to add the EncapsulatedTimeStamp to the signature.
* Note: If the signed XML contains multiple signatures, the signature modified is the one 
* indicated by the dsig.Selector property.
* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.StringBuilder')
loSbOut = CreateObject('Chilkat.StringBuilder')
lnSuccess = loDsig.AddEncapsulatedTimeStamp(loJson,loSbOut)
IF (lnSuccess = 0) THEN
    ? loDsig.LastErrorText
    RELEASE loSbXml
    RELEASE loDsig
    RELEASE loJson
    RELEASE loSbOut
    CANCEL
ENDIF

loSbOut.WriteFile("qa_output/addedEncapsulatedTimeStamp.xml","utf-8",0)

* The EncapsulatedTimeStamp can be validated when validating the signature by adding the VerifyEncapsulatedTimeStamp
* keyword to UncommonOptions.  See here:

* ----------------------------------------
* Verify the signatures we just produced...
* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.XmlDSig')
loVerifier = CreateObject('Chilkat.XmlDSig')
lnSuccess = loVerifier.LoadSignatureSb(loSbOut)
IF (lnSuccess <> 1) THEN
    ? loVerifier.LastErrorText
    RELEASE loSbXml
    RELEASE loDsig
    RELEASE loJson
    RELEASE loSbOut
    RELEASE loVerifier
    CANCEL
ENDIF

* Add "VerifyEncapsulatedTimeStamp" to the UncommonOptions to also verify any EncapsulatedTimeStamps
loVerifier.UncommonOptions = "VerifyEncapsulatedTimeStamp"

lnNumSigs = loVerifier.NumSignatures
lnVerifyIdx = 0
DO WHILE lnVerifyIdx < lnNumSigs
    loVerifier.Selector = lnVerifyIdx
    lnVerified = loVerifier.VerifySignature(1)
    IF (lnVerified <> 1) THEN
        ? loVerifier.LastErrorText
        RELEASE loSbXml
        RELEASE loDsig
        RELEASE loJson
        RELEASE loSbOut
        RELEASE loVerifier
        CANCEL
    ENDIF

    lnVerifyIdx = lnVerifyIdx + 1
ENDDO
? "All signatures were successfully verified."

RELEASE loSbXml
RELEASE loDsig
RELEASE loJson
RELEASE loSbOut
RELEASE loVerifier