(Lianja) 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.

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// 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("CkPkcs11")

// 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
loPkcs11.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
lcPin = "user:password"
lnUserType = 1

// Establish a PKCS logged-on session using the driver (.so, .dylib, or .dll) as specified in the SharedLibPath above.
llSuccess = loPkcs11.QuickSession(lnUserType,lcPin)
if (llSuccess = .F.) then
    ? loPkcs11.LastErrorText
    release loPkcs11
    return
endif

loCert = createobject("CkCert")
llSuccess = loCert.LoadFromFile("qa_data/certs/myCert.cer")
if (llSuccess = .F.) then
    ? loCert.LastErrorText
    release loPkcs11
    release loCert
    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.
llSuccess = loCert.LinkPkcs11(loPkcs11)
if (llSuccess = .F.) then
    ? loCert.LastErrorText
    release loPkcs11
    release loCert
    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..

loPdf = createobject("CkPdf")

// Load a PDF to be signed.
llSuccess = loPdf.LoadFile("qa_data/pdf/hello.pdf")
if (llSuccess = .F.) then
    ? loPdf.LastErrorText
    llSuccess = loPkcs11.CloseSession()
    release loPkcs11
    release loCert
    release loPdf
    return
endif

loJson = createobject("CkJsonObject")

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.
llSuccess = loPdf.SetSigningCert(loCert)

llSuccess = loPdf.SignPdf(loJson,"qa_output/out.pdf")
if (llSuccess = .F.) then
    ? loPdf.LastErrorText
    llSuccess = loPkcs11.CloseSession()
    release loPkcs11
    release loCert
    release loPdf
    release loJson
    return
endif

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

// Revert to an unauthenticated session by calling Logout.
llSuccess = loPkcs11.Logout()
if (llSuccess = .F.) then
    ? loPkcs11.LastErrorText
    llSuccess = loPkcs11.CloseSession()
    release loPkcs11
    release loCert
    release loPdf
    release loJson
    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).
llSuccess = loPkcs11.CloseSession()
if (llSuccess = .F.) then
    ? loPkcs11.LastErrorText
    release loPkcs11
    release loCert
    release loPdf
    release loJson
    return
endif

? "Success."


release loPkcs11
release loCert
release loPdf
release loJson