Xojo Plugin

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.

Xojo Plugin

Dim success As Boolean
success = 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 New Chilkat.StringBuilder
success = sbXml.LoadFile("qa_data/xml_dsig_valid_samples/encapsulatedTimestamp_not_yet_added.xml","utf-8")
If (success = False) Then
    System.DebugLog("Failed to load the XML file.")
    Return
End If

Dim dsig As New Chilkat.XmlDSig
success = dsig.LoadSignatureSb(sbXml)
If (success = False) Then
    System.DebugLog(dsig.LastErrorText)
    Return
End If

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

// Specify the timestamping authority URL
Dim json As New Chilkat.JsonObject
success = json.UpdateString("timestampToken.tsaUrl","http://timestamp.digicert.com")
success = 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 New Chilkat.StringBuilder
success = dsig.AddEncapsulatedTimeStamp(json,sbOut)
If (success = False) Then
    System.DebugLog(dsig.LastErrorText)
    Return
End If

success = 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 New Chilkat.XmlDSig
success = verifier.LoadSignatureSb(sbOut)
If (success <> True) Then
    System.DebugLog(verifier.LastErrorText)
    Return
End If

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

Dim numSigs As Int32
numSigs = verifier.NumSignatures
Dim verifyIdx As Int32
verifyIdx = 0
While verifyIdx < numSigs
    verifier.Selector = verifyIdx
    Dim verified As Boolean
    verified = verifier.VerifySignature(True)
    If (verified <> True) Then
        System.DebugLog(verifier.LastErrorText)
        Return
    End If

    verifyIdx = verifyIdx + 1
Wend
System.DebugLog("All signatures were successfully verified.")