Visual FoxPro

PKCS11 Sign PDF using Certificate and Private Key on Smart Card / USB Token

See more PKCS11 Examples

Sample code showing how to use PKCS11 to sign a PDF with a certificate and private key stored on a smart card or USB token.

Note: This example requires Chilkat v9.5.0.96 or later.

Visual FoxPro

LOCAL lnSuccess
LOCAL loPkcs11
LOCAL lcPin
LOCAL lnUserType
LOCAL loCert
LOCAL loPdf
LOCAL loJson
LOCAL i

lnSuccess = 0

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

* Note: Chilkat's PKCS11 implementation runs on Windows, Linux, Mac OS X, and other supported operating systems.

loPkcs11 = CreateObject('Chilkat.Pkcs11')

loPkcs11.SharedLibPath = "C:/Program Files (x86)/Gemalto/IDGo 800 PKCS#11/IDPrimePKCS1164.dll"
lcPin = "0000"
lnUserType = 1

* Establish a PKCS11 logged-on session using the driver (.so, .dylib, or .dll) as specified in the SharedLibPath above.
lnSuccess = loPkcs11.QuickSession(lnUserType,lcPin)
IF (lnSuccess = 0) THEN
    ? loPkcs11.LastErrorText
    RELEASE loPkcs11
    CANCEL
ENDIF

* Get the certificate (on the smart card) that has a private key.
* There are other ways to locate a certificate on the HSM.
* This example assumes there is a single certificate w/ private key.
loCert = CreateObject('Chilkat.Cert')
lnSuccess = loPkcs11.FindCert("privateKey","",loCert)
IF (lnSuccess = 1) THEN
    ? "Cert with private key: " + loCert.SubjectCN
ELSE
    ? "No certificates having a private key were found."
    lnSuccess = loPkcs11.CloseSession()
    RELEASE loPkcs11
    RELEASE loCert
    CANCEL
ENDIF

* --------------------------------------------------------------------------
* At this point, we have the cert to be used for signing.
* Our PDF signing code is the same as for a cert obtained from any other source..

loPdf = CreateObject('Chilkat.Pdf')

* Load a PDF to be signed.
lnSuccess = loPdf.LoadFile("qa_data/pdf/hello.pdf")
IF (lnSuccess = 0) THEN
    ? loPdf.LastErrorText
    lnSuccess = loPkcs11.CloseSession()
    RELEASE loPkcs11
    RELEASE loCert
    RELEASE loPdf
    CANCEL
ENDIF

loJson = CreateObject('Chilkat.JsonObject')

loJson.UpdateInt("page",1)
loJson.UpdateString("appearance.y","top")
loJson.UpdateString("appearance.x","left")
loJson.UpdateString("appearance.fontScale","10.0")
loJson.UpdateString("signingAlgorithm","pss")
loJson.UpdateString("hashAlgorithm","sha256")

i = 0
loJson.I = i
loJson.UpdateString("appearance.text[i]","Digitaly signed by: Xyz Widgets, Inc.")
i = i + 1
loJson.I = i
loJson.UpdateString("appearance.text[i]","current_dt")
i = i + 1
loJson.I = i
loJson.UpdateString("appearance.text[i]","blah blah blah")

* The certificate is internally linked to the Pkcs11 object, which is currently in an authenticated session.
lnSuccess = loPdf.SetSigningCert(loCert)

lnSuccess = loPdf.SignPdf(loJson,"qa_output/out.pdf")
IF (lnSuccess = 0) THEN
    ? loPdf.LastErrorText
    lnSuccess = loPkcs11.CloseSession()
    RELEASE loPkcs11
    RELEASE loCert
    RELEASE loPdf
    RELEASE loJson
    CANCEL
ENDIF

* --------------------------------------------------------------------------

* Revert to an unauthenticated session by calling Logout.
lnSuccess = loPkcs11.Logout()
IF (lnSuccess = 0) THEN
    ? loPkcs11.LastErrorText
    lnSuccess = loPkcs11.CloseSession()
    RELEASE loPkcs11
    RELEASE loCert
    RELEASE loPdf
    RELEASE loJson
    CANCEL
ENDIF

* When finished, close the session.
* It is important to close the session (memory leaks will occur if the session is not properly closed).
lnSuccess = loPkcs11.CloseSession()
IF (lnSuccess = 0) THEN
    ? loPkcs11.LastErrorText
    RELEASE loPkcs11
    RELEASE loCert
    RELEASE loPdf
    RELEASE loJson
    CANCEL
ENDIF

? "Success."

RELEASE loPkcs11
RELEASE loCert
RELEASE loPdf
RELEASE loJson