CkPython Requires Chilkat v11.7.0+

Encrypt a PDF for a Certificate Instead of a Password

See more PDF Protection Examples

Demonstrates certificate security, where a PDF is encrypted for one or more recipients and each opens it with their own certificate and private key. No password is involved. Only the public certificate of a recipient is needed to encrypt. Each recipient has its own permissions, and the changeSecurity permission gives a recipient owner rights. PreLoadCheck tells an application that a file is certificate-encrypted and which certificates can open it. A PDF that cannot be opened, because no matching certificate and private key were provided, fails to load. CkPython

import sys
import chilkat

success = False

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

#  The PDF used in this example is available at two_page_memo.pdf

#  The recipient's certificate.  Only the public certificate is needed to encrypt.
recipient = chilkat.CkCert()
success = recipient.LoadFromFile("qa_data/certs/recipient.cer")
if (success == False):
    print(recipient.lastErrorText())
    sys.exit()

pdf = chilkat.CkPdf()
success = pdf.LoadFile("qa_data/pdf/two_page_memo.pdf")
if (success == False):
    print(pdf.lastErrorText())
    sys.exit()

#  Call AddEncryptCert once for each recipient.
success = pdf.AddEncryptCert(recipient)
if (success == False):
    print(pdf.lastErrorText())
    sys.exit()

#  recipientPermissions[0] belongs to the first certificate added.  changeSecurity gives that
#  recipient owner rights, so the file can be managed later.
json = chilkat.CkJsonObject()
json.UpdateString("method","certificate")
json.UpdateBool("recipientPermissions[0].changeSecurity",True)

jsonOut = chilkat.CkJsonObject()
success = pdf.Protection("encrypt",json,jsonOut)
if (success == False):
    print(pdf.lastErrorText())
    sys.exit()

print("method: " + jsonOut.stringOf("pending.method"))
print("algorithm: " + jsonOut.stringOf("pending.algorithm"))
print("recipients: " + str(jsonOut.SizeOfArray("pending.recipients")))

success = pdf.WriteFile("qa_output/memo_for_recipient.pdf")
if (success == False):
    print(pdf.lastErrorText())
    sys.exit()

#  PreLoadCheck says how the file is protected, without loading it.
reader = chilkat.CkPdf()
info = chilkat.CkJsonObject()
success = reader.PreLoadCheck("qa_output/memo_for_recipient.pdf",info)
if (success == False):
    print(reader.lastErrorText())
    sys.exit()

print("saved file, method: " + info.stringOf("method"))
print("saved file, recipients: " + str(info.SizeOfArray("recipients")))

#  The recipient opens it with the certificate and its private key, here from a .pfx file.
#  (On Windows, a certificate that is installed in the Windows certificate store with its private
#  key is found automatically when the PDF is loaded, and SetDecryptCert is not needed for it.)
myCert = chilkat.CkCert()
success = myCert.LoadPfxFile("qa_data/pfx/recipient.pfx","pfx-password")
if (success == False):
    print(myCert.lastErrorText())
    sys.exit()

success = reader.SetDecryptCert(myCert)
if (success == False):
    print(reader.lastErrorText())
    sys.exit()

success = reader.LoadFile("qa_output/memo_for_recipient.pdf")
if (success == False):
    print(reader.lastErrorText())
    sys.exit()

empty = chilkat.CkJsonObject()
loadedInfo = chilkat.CkJsonObject()
success = reader.Protection("getInfo",empty,loadedInfo)
if (success == False):
    print(reader.lastErrorText())
    sys.exit()

print("opened with: " + loadedInfo.stringOf("loaded.openedWith"))
print("pages: " + str(reader.get_NumPages()))

#  Sample output:

#  method: certificate
#  algorithm: aes-256
#  recipients: 1
#  saved file, method: certificate
#  saved file, recipients: 1
#  opened with: certificate
#  pages: 2