Ruby

Sign a PDF using SmartCard or HSM (Hardware Security Module)

See more PDF Signatures Examples

This example demonstrates how to a sign a PDF using a smartcard or HSM (hardware security module).

Note: This example requires Chilkat v9.5.0.88 or greater.

Ruby

require 'chilkat'

success = false

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

pdf = Chilkat::CkPdf.new()

# Load a PDF to be signed.
# The "hello.pdf" is available at https://chilkatsoft.com/hello.pdf
success = pdf.LoadFile("qa_data/pdf/hello.pdf")
if (success == false)
    print pdf.lastErrorText() + "\n";
    exit
end

# Options for signing are specified in JSON.
json = Chilkat::CkJsonObject.new()

# In most cases, the signingCertificateV2 and signingTime attributes are required.
json.UpdateInt("signingCertificateV2",1)
json.UpdateInt("signingTime",1)

# Put the signature on page 1, top left
json.UpdateInt("page",1)
json.UpdateString("appearance.y","top")
json.UpdateString("appearance.x","left")

# Use a font scale of 10.0
json.UpdateString("appearance.fontScale","10.0")

# In this example, the appearance of the digital signature will contain three lines:
# 1) The signing certificate's common name
# 2) The current date/time
# 3) Some arbitrary text.
# The keyword "cert_cn" is replaced with the Certificate's Subject Common Name.
# The keyword "current_dt" is replaced with the current date/time.
# Any number of appearance text lines can be added.
json.UpdateString("appearance.text[0]","Digitally signed by: cert_cn")
json.UpdateString("appearance.text[1]","current_dt")
json.UpdateString("appearance.text[2]","The crazy brown fox jumps over the lazy dog.")

# Use a certificate on a smartcard or USB token.
cert = Chilkat::CkCert.new()

# Provide the smartcard PIN.
# Set the smartcard PIN prior to calling LoadFromSmartcard.
# If the PIN is not explicitly provided here, the Windows OS should
# display a dialog for the PIN.
cert.put_SmartCardPin("123456")

# Load the certificate on the smartcard currently in the reader (or on the USB token).
# Pass an empty string to allow Chilkat to automatically choose the CSP (Cryptographi Service Provider).
# See Load Certificate on Smartcard for information about explicitly selecting a particular CSP.
success = cert.LoadFromSmartcard("")
if (success == false)
    print cert.lastErrorText() + "\n";
    exit
end

# Tell the pdf object to use the certificate for signing.
success = pdf.SetSigningCert(cert)
if (success == false)
    print pdf.lastErrorText() + "\n";
    exit
end

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

print "The PDF has been successfully cryptographically signed using an HSM." + "\n";