PowerBuilder

Sign PDF with Timestamp from TSA (Timestamp Server Authority)

See more PDF Signatures Examples

This example demonstrates how to a sign a PDF that is both long-term validation (LTV) enabled and includes a validating timestamp from a TSA (Timestamp Server Authority). 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)

// Tell Chilkat to create an LTV-enabled (long term validation) signature.
// See PDF Long-Term Validation (LTV) Signature Example for more detailed comments about "ltvOcsp".
loo_Json.UpdateBool("ltvOcsp",1)

// Tell Chilkat to request a timestamp from a TSA server and include the timestamp token (1.2.840.113549.1.9.16.2.14)
// in the CMS signature's authentication attributes
loo_Json.UpdateBool("timestampToken.enabled",1)

// In this example, we'll use a free TSA server (timestamp.digicert.com), but you may want to use your own timestamp authority server.
loo_Json.UpdateString("timestampToken.tsaUrl","http://timestamp.digicert.com")

// If the timestamp server requires a username/password, do the following.  Otherwise omit the following few lines of code.
loo_Json.UpdateString("timestampToken.tsaUsername","the_tsa_username")
loo_Json.UpdateString("timestampToken.tsaPassword","the_tsa_password")

// When requesting the timestamp token, ask the server to include its certificate in the timestamp token response.
// This allows for the timestamp server's certificate to be included in the LTV validation (i.e. if the timestamp server
// has an OCSP URL, then Chilkat will also do the OCSP request for the timestamp server's certificate.)
loo_Json.UpdateBool("timestampToken.requestTsaCert",1)

// 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 with a TSA timestamp.")

// 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_with_timestamp.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 TSA timestamp and long-term validation."

// If you open the Signature Panel in Adobe Acrobat, it will indicate that the signature is LTV enabled
// and contains an embedded timestamp:
// (image:https://example-code.com/images/ltv_signature_with_timestamp.jpg/endImage)


destroy loo_Pdf
destroy loo_Json
destroy loo_Cert