Xbase++

Sign PDF in the Cloud using AWS CloudHSM

See more Signing in the Cloud Examples

Demonstrates how to sign a PDF using AWS CloudHSM. The signing of the hash happens on a hardware token in AWS CloudHSM. Everything else involving the updating the PDF to add the signature happens locally within Chilkat.

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

Xbase++

LOCAL nSuccess
LOCAL oPkcs11
LOCAL cPin
LOCAL nUserType
LOCAL oCert
LOCAL oPdf
LOCAL oJson
LOCAL i

nSuccess := 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.

oPkcs11 := CreateObject("Chilkat.Pkcs11")

//  Provide the path to the AWS CloudHSM PKCS11 driver.
//  This example runs on Windows, so we'll provide the CloudHSM DLL.
//  If your code runs on Linux, the CloudHSM driver might be at /opt/cloudhsm/lib/libcloudhsm_pkcs11.so
oPkcs11:SharedLibPath := "C:\Program Files\Amazon\CloudHSM\lib\cloudhsm_pkcs11.dll"

//  Your PIN should be a string containing your crypto user's login and password, with a colon char delimiting.
//  See https://docs.aws.amazon.com/cloudhsm/latest/userguide/pkcs11-pin.html
cPin := "user:password"
nUserType := 1

//  Establish a PKCS logged-on session using the driver (.so, .dylib, or .dll) as specified in the SharedLibPath above.
nSuccess := oPkcs11:QuickSession(nUserType, cPin)
IF (nSuccess == 0)
    ? oPkcs11:LastErrorText
    oPkcs11:destroy()
    RETURN
ENDIF

oCert := CreateObject("Chilkat.Cert")
nSuccess := oCert:LoadFromFile("qa_data/certs/myCert.cer")
IF (nSuccess == 0)
    ? oCert:LastErrorText
    oPkcs11:destroy()
    oCert:destroy()
    RETURN
ENDIF

//  Tell the certificate to link with the PKCS11 session.
//  The cert's private key should be installed on the CloudHSM.
//  If there are multiple private keys on the CloudHSM, then Chilkat will automatically
//  locate and use the private key corresponding to the certificate.
nSuccess := oCert:LinkPkcs11(oPkcs11)
IF (nSuccess == 0)
    ? oCert:LastErrorText
    oPkcs11:destroy()
    oCert:destroy()
    RETURN
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..

oPdf := CreateObject("Chilkat.Pdf")

//  Load a PDF to be signed.
nSuccess := oPdf:LoadFile("qa_data/pdf/hello.pdf")
IF (nSuccess == 0)
    ? oPdf:LastErrorText
    nSuccess := oPkcs11:CloseSession()
    oPkcs11:destroy()
    oCert:destroy()
    oPdf:destroy()
    RETURN
ENDIF

oJson := CreateObject("Chilkat.JsonObject")

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

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

//  The certificate is internally linked to the Pkcs11 object, which is currently in an authenticated session.
nSuccess := oPdf:SetSigningCert(oCert)

nSuccess := oPdf:SignPdf(oJson, "qa_output/out.pdf")
IF (nSuccess == 0)
    ? oPdf:LastErrorText
    nSuccess := oPkcs11:CloseSession()
    oPkcs11:destroy()
    oCert:destroy()
    oPdf:destroy()
    oJson:destroy()
    RETURN
ENDIF

//  --------------------------------------------------------------------------

//  Revert to an unauthenticated session by calling Logout.
nSuccess := oPkcs11:Logout()
IF (nSuccess == 0)
    ? oPkcs11:LastErrorText
    nSuccess := oPkcs11:CloseSession()
    oPkcs11:destroy()
    oCert:destroy()
    oPdf:destroy()
    oJson:destroy()
    RETURN
ENDIF

//  When finished, close the session.
//  It is important to close the session (memory leaks will occur if the session is not properly closed).
nSuccess := oPkcs11:CloseSession()
IF (nSuccess == 0)
    ? oPkcs11:LastErrorText
    oPkcs11:destroy()
    oCert:destroy()
    oPdf:destroy()
    oJson:destroy()
    RETURN
ENDIF

? "Success."

oPkcs11:destroy()
oCert:destroy()
oPdf:destroy()
oJson:destroy()