Perl 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. Perl

use chilkat();

$success = 0;

#  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->new();
$success = $recipient->LoadFromFile("qa_data/certs/recipient.cer");
if ($success == 0) {
    print $recipient->lastErrorText() . "\r\n";
    exit;
}

$pdf = chilkat::CkPdf->new();
$success = $pdf->LoadFile("qa_data/pdf/two_page_memo.pdf");
if ($success == 0) {
    print $pdf->lastErrorText() . "\r\n";
    exit;
}

#  Call AddEncryptCert once for each recipient.
$success = $pdf->AddEncryptCert($recipient);
if ($success == 0) {
    print $pdf->lastErrorText() . "\r\n";
    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->new();
$json->UpdateString("method","certificate");
$json->UpdateBool("recipientPermissions[0].changeSecurity",1);

$jsonOut = chilkat::CkJsonObject->new();
$success = $pdf->Protection("encrypt",$json,$jsonOut);
if ($success == 0) {
    print $pdf->lastErrorText() . "\r\n";
    exit;
}

print "method: " . $jsonOut->stringOf("pending.method") . "\r\n";
print "algorithm: " . $jsonOut->stringOf("pending.algorithm") . "\r\n";
print "recipients: " . $jsonOut->SizeOfArray("pending.recipients") . "\r\n";

$success = $pdf->WriteFile("qa_output/memo_for_recipient.pdf");
if ($success == 0) {
    print $pdf->lastErrorText() . "\r\n";
    exit;
}

#  PreLoadCheck says how the file is protected, without loading it.
$reader = chilkat::CkPdf->new();
$info = chilkat::CkJsonObject->new();
$success = $reader->PreLoadCheck("qa_output/memo_for_recipient.pdf",$info);
if ($success == 0) {
    print $reader->lastErrorText() . "\r\n";
    exit;
}

print "saved file, method: " . $info->stringOf("method") . "\r\n";
print "saved file, recipients: " . $info->SizeOfArray("recipients") . "\r\n";

#  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->new();
$success = $myCert->LoadPfxFile("qa_data/pfx/recipient.pfx","pfx-password");
if ($success == 0) {
    print $myCert->lastErrorText() . "\r\n";
    exit;
}

$success = $reader->SetDecryptCert($myCert);
if ($success == 0) {
    print $reader->lastErrorText() . "\r\n";
    exit;
}

$success = $reader->LoadFile("qa_output/memo_for_recipient.pdf");
if ($success == 0) {
    print $reader->lastErrorText() . "\r\n";
    exit;
}

$empty = chilkat::CkJsonObject->new();
$loadedInfo = chilkat::CkJsonObject->new();
$success = $reader->Protection("getInfo",$empty,$loadedInfo);
if ($success == 0) {
    print $reader->lastErrorText() . "\r\n";
    exit;
}

print "opened with: " . $loadedInfo->stringOf("loaded.openedWith") . "\r\n";
print "pages: " . $reader->get_NumPages() . "\r\n";

#  Sample output:

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