Lua Requires Chilkat v9.5.0.96+

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. Lua

local chilkat = require("chilkat")

-- 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.

local pkcs11 = chilkat.Pkcs11.new()

-- 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
pkcs11.shared_lib_path = "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
local pin = "user:password"
local userType = 1

-- Establish a PKCS logged-on session using the driver (.so, .dylib, or .dll) as specified in the SharedLibPath above.
local success = pkcs11:quick_session(userType, pin)
if not success then
    print(pkcs11.last_error_text)
    return
end

local cert = chilkat.Cert.new()
success = cert:load_from_file("qa_data/certs/myCert.cer")
if not success then
    print(cert.last_error_text)
    return
end

-- 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.
success = cert:link_pkcs11(pkcs11)
if not success then
    print(cert.last_error_text)
    return
end

-- --------------------------------------------------------------------------
-- 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..

local pdf = chilkat.Pdf.new()

-- Load a PDF to be signed.
success = pdf:load_file("qa_data/pdf/hello.pdf")
if not success then
    print(pdf.last_error_text)
    success = pkcs11:close_session()
    return
end

local json = chilkat.JsonObject.new()

json:update_int("page", 1)
json:update_string("appearance.y", "top")
json:update_string("appearance.x", "left")
json:update_string("appearance.fontScale", "10.0")
json:update_string("signingAlgorithm", "pss")
json:update_string("hashAlgorithm", "sha256")

local i = 0
json.i = i
json:update_string("appearance.text[i]", "Digitaly signed by: Xyz Widgets, Inc.")
i = i + 1
json.i = i
json:update_string("appearance.text[i]", "current_dt")
i = i + 1
json.i = i
json:update_string("appearance.text[i]", "blah blah blah")

-- The certificate is internally linked to the Pkcs11 object, which is currently in an authenticated session.
success = pdf:set_signing_cert(cert)

success = pdf:sign_pdf(json, "qa_output/out.pdf")
if not success then
    print(pdf.last_error_text)
    success = pkcs11:close_session()
    return
end

-- --------------------------------------------------------------------------

-- Revert to an unauthenticated session by calling Logout.
success = pkcs11:logout()
if not success then
    print(pkcs11.last_error_text)
    success = pkcs11:close_session()
    return
end

-- When finished, close the session.
-- It is important to close the session (memory leaks will occur if the session is not properly closed).
success = pkcs11:close_session()
if not success then
    print(pkcs11.last_error_text)
    return
end

print("Success.")