B4X

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.

B4X

Dim success As Boolean = False

'  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.
Dim sbXml As ChilkatStringBuilder
sbXml.Initialize
success = sbXml.LoadFile("qa_data/xml_dsig_valid_samples/encapsulatedTimestamp_not_yet_added.xml", "utf-8")
If success = False Then
    Log("Failed to load the XML file.")
    Return
End If


Dim dsig As ChilkatXmlDSig
dsig.Initialize
success = dsig.LoadSignatureSb(sbXml)
If success = False Then
    Log(dsig.LastErrorText)
    Return
End If


If dsig.HasEncapsulatedTimeStamp = True Then
    Log("This signed XML already has an EncapsulatedTimeStamp")
    Return
End If


'  Specify the timestamping authority URL
Dim json As ChilkatJsonObject
json.Initialize
json.UpdateString("timestampToken.tsaUrl", "http://timestamp.digicert.com")
json.UpdateBool("timestampToken.requestTsaCert", True)

'  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.
Dim sbOut As ChilkatStringBuilder
sbOut.Initialize
success = dsig.AddEncapsulatedTimeStamp(json, sbOut)
If success = False Then
    Log(dsig.LastErrorText)
    Return
End If


sbOut.WriteFile("qa_output/addedEncapsulatedTimeStamp.xml", "utf-8", False)

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

'  ----------------------------------------
'  Verify the signatures we just produced...
Dim verifier As ChilkatXmlDSig
verifier.Initialize
success = verifier.LoadSignatureSb(sbOut)
If success <> True Then
    Log(verifier.LastErrorText)
    Return
End If


'  Add "VerifyEncapsulatedTimeStamp" to the UncommonOptions to also verify any EncapsulatedTimeStamps
verifier.UncommonOptions = "VerifyEncapsulatedTimeStamp"

Dim numSigs As Int = verifier.NumSignatures
Dim verifyIdx As Int = 0
Do While verifyIdx < numSigs
    verifier.Selector = verifyIdx
    Dim verified As Boolean = verifier.VerifySignature(True)
    If verified <> True Then
        Log(verifier.LastErrorText)
        Return
    End If

    verifyIdx = verifyIdx + 1
Loop
Log("All signatures were successfully verified.")