(Ruby) 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.

Chilkat Ruby Downloads install from rubygems.org gem install chilkat or download... Ruby Library for Windows, MacOS, Linux, Alpine Linux

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.

pkcs11 = Chilkat::CkPkcs11.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.put_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
pin = "user:password"
userType = 1

# Establish a PKCS logged-on session using the driver (.so, .dylib, or .dll) as specified in the SharedLibPath above.
success = pkcs11.QuickSession(userType,pin)
if (success == false)
    print pkcs11.lastErrorText() + "\n";
    exit
end

cert = Chilkat::CkCert.new()
success = cert.LoadFromFile("qa_data/certs/myCert.cer")
if (success == false)
    print cert.lastErrorText() + "\n";
    exit
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.LinkPkcs11(pkcs11)
if (success == false)
    print cert.lastErrorText() + "\n";
    exit
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..

pdf = Chilkat::CkPdf.new()

# Load a PDF to be signed.
success = pdf.LoadFile("qa_data/pdf/hello.pdf")
if (success == false)
    print pdf.lastErrorText() + "\n";
    success = pkcs11.CloseSession()
    exit
end

json = Chilkat::CkJsonObject.new()

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

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

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

success = pdf.SignPdf(json,"qa_output/out.pdf")
if (success == false)
    print pdf.lastErrorText() + "\n";
    success = pkcs11.CloseSession()
    exit
end

# --------------------------------------------------------------------------

# Revert to an unauthenticated session by calling Logout.
success = pkcs11.Logout()
if (success == false)
    print pkcs11.lastErrorText() + "\n";
    success = pkcs11.CloseSession()
    exit
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.CloseSession()
if (success == false)
    print pkcs11.lastErrorText() + "\n";
    exit
end

print "Success." + "\n";