PowerBuilder

Sign PDF with Long-Term Validation (LTV Enabled)

See more PDF Signatures Examples

This example demonstrates how to a sign a PDF with long-term validation (LTV) enabled.

Note: This example requires Chilkat v9.5.0.85 or greater.

PowerBuilder

integer li_rc
integer li_Success
oleobject loo_Pdf
oleobject loo_Json
oleobject loo_Cert

li_Success = 0

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

loo_Pdf = create oleobject
li_rc = loo_Pdf.ConnectToNewObject("Chilkat.Pdf")
if li_rc < 0 then
    destroy loo_Pdf
    MessageBox("Error","Connecting to COM object failed")
    return
end if

// Load a PDF to be signed.
// The "hello.pdf" is available at https://chilkatsoft.com/hello.pdf
li_Success = loo_Pdf.LoadFile("qa_data/pdf/hello.pdf")
if li_Success = 0 then
    Write-Debug loo_Pdf.LastErrorText
    destroy loo_Pdf
    return
end if

// Options for signing are specified in JSON.
loo_Json = create oleobject
li_rc = loo_Json.ConnectToNewObject("Chilkat.JsonObject")

// In most cases, the signingCertificateV2 and signingTime attributes are required.
loo_Json.UpdateInt("signingCertificateV2",1)
loo_Json.UpdateInt("signingTime",1)

// Add the "ltvOcsp" instruction to the JSON passed to SignPdf.
// This is what causes Chilkat to create an LTV-enabled signature.
// 
// If we are signing a PDF that already has signatures, then the existing signatures
// are automatically verified, and Chilkat will do OCSP certificate status checking (if possible) 
// for those certs in existing signatures (including certs in the certificate chains) 
// that do not yet have a valid OCSP response in the DSS (Document Security Store).
// Chilkat will add the OCSP responses to the /OCSPs in the Document Security Store (/DSS).
// Also, and certificates from existing signatures not yet in the DSS are added to the /Certs 
// in the DSS.
// 
// Also, the "ltvOcsp" causes Chilkat to add the pdfRevocationInfoArchival authenticated attribute
// to the CMS signature.  The pdfRevocationInfoArchival attribute (1.2.840.113583.1.1.8)
// contains OCSP responses and the CRL for the issuer of the signing certificate.
// Therefore, Chilkat will send an OCSP request to the signing certificate's OCSP URl (if one exists)
// and will download the CRL from the issuer certificate's CRL Distribution Point (if one exists).
loo_Json.UpdateBool("ltvOcsp",1)

// -----------------------------------------------------------------------------------
// Note: If Chilkat produces a signed PDF, but the signature is not LTV-enabled,
// the cause might be related to a failure to download CRL's or OCSP requests.
// See Possible Solution for Failure to Produce LTV-enabled PDF Signature
// -----------------------------------------------------------------------------------
// You can add the following to UncommonOptions to get detailed information about the CRL and OCSP requests
// You shouldn't set the following logging options unless there is a need, because it adds a large amount of information to the LastErrorText.
loo_Pdf.UncommonOptions = "LOG_OCSP_HTTP,LOG_CRL_HTTP"

// Define the appearance of the signature.
loo_Json.UpdateInt("page",1)
loo_Json.UpdateString("appearance.y","top")
loo_Json.UpdateString("appearance.x","left")
loo_Json.UpdateString("appearance.fontScale","10.0")
loo_Json.UpdateString("appearance.text[0]","Digitally signed by: cert_cn")
loo_Json.UpdateString("appearance.text[1]","current_dt")
loo_Json.UpdateString("appearance.text[2]","This is an LTV-enabled signature.")

// Load the signing certificate. (Use your own certificate.)
loo_Cert = create oleobject
li_rc = loo_Cert.ConnectToNewObject("Chilkat.Cert")

li_Success = loo_Cert.LoadPfxFile("qa_data/pfx/myPdfSigningCert.pfx","pfxPassword")
if li_Success = 0 then
    Write-Debug loo_Cert.LastErrorText
    destroy loo_Pdf
    destroy loo_Json
    destroy loo_Cert
    return
end if

// Tell the pdf object to use the certificate for signing.
li_Success = loo_Pdf.SetSigningCert(loo_Cert)
if li_Success = 0 then
    Write-Debug loo_Pdf.LastErrorText
    destroy loo_Pdf
    destroy loo_Json
    destroy loo_Cert
    return
end if

li_Success = loo_Pdf.SignPdf(loo_Json,"qa_output/hello_ltv_signed.pdf")
if li_Success = 0 then
    Write-Debug loo_Pdf.LastErrorText
    destroy loo_Pdf
    destroy loo_Json
    destroy loo_Cert
    return
end if

Write-Debug "The PDF has been successfully cryptographically signed with long-term validation."

// If you open the Signature Panel in Adobe Acrobat, it will indicate that the signature is LTV enabled
// as shown here:
// (image:https://example-code.com/images/ltv_signature.jpg/endImage)


destroy loo_Pdf
destroy loo_Json
destroy loo_Cert