Perl Requires Chilkat v11.7.0+

Choose the PDF Encryption Algorithm: AES-256, AES-128 or RC4

See more PDF Protection Examples

Demonstrates the algorithmChoice option of the encrypt operation. aes-256 is the default and the one to use unless an older reader must open the file. aes-128 is for readers that predate AES-256. rc4-128 and rc4-40 are broken ciphers kept only for very old readers. Each algorithm needs a minimum PDF version, and the file header is raised to it when the PDF is saved, never lowered. A PDF saved with RC4 is written with a classic cross-reference table so that those old readers can parse it. 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

$json = chilkat::CkJsonObject->new();
$jsonOut = chilkat::CkJsonObject->new();
$info = chilkat::CkJsonObject->new();

#  AES-256, the default.  Saved as PDF 1.7 with Adobe extension level 8.
$pdf1 = chilkat::CkPdf->new();
$success = $pdf1->LoadFile("qa_data/pdf/two_page_memo.pdf");
if ($success == 0) {
    print $pdf1->lastErrorText() . "\r\n";
    exit;
}

$pdf1->put_UserPassword("user-secret");
$pdf1->put_OwnerPassword("owner-secret");
$json->UpdateString("algorithmChoice","aes-256");
$success = $pdf1->Protection("encrypt",$json,$jsonOut);
if ($success == 0) {
    print $pdf1->lastErrorText() . "\r\n";
    exit;
}

print "aes-256 will be saved as PDF " . $jsonOut->stringOf("pending.pdfVersion") . ", Adobe extension level " . $jsonOut->IntOf("pending.adobeExtensionLevel") . "\r\n";
$success = $pdf1->WriteFile("qa_output/memo_aes256.pdf");
if ($success == 0) {
    print $pdf1->lastErrorText() . "\r\n";
    exit;
}

$success = $pdf1->PreLoadCheck("qa_output/memo_aes256.pdf",$info);
if ($success == 0) {
    print $pdf1->lastErrorText() . "\r\n";
    exit;
}

print "  saved file: " . $info->stringOf("algorithm") . ", PDF " . $info->stringOf("pdfVersion") . "\r\n";

#  AES-128, for readers that predate AES-256.  Saved as PDF 1.6.
$pdf2 = chilkat::CkPdf->new();
$success = $pdf2->LoadFile("qa_data/pdf/two_page_memo.pdf");
if ($success == 0) {
    print $pdf2->lastErrorText() . "\r\n";
    exit;
}

$pdf2->put_UserPassword("user-secret");
$pdf2->put_OwnerPassword("owner-secret");
$json->UpdateString("algorithmChoice","aes-128");
$success = $pdf2->Protection("encrypt",$json,$jsonOut);
if ($success == 0) {
    print $pdf2->lastErrorText() . "\r\n";
    exit;
}

print "aes-128 will be saved as PDF " . $jsonOut->stringOf("pending.pdfVersion") . "\r\n";
$success = $pdf2->WriteFile("qa_output/memo_aes128.pdf");
if ($success == 0) {
    print $pdf2->lastErrorText() . "\r\n";
    exit;
}

$success = $pdf2->PreLoadCheck("qa_output/memo_aes128.pdf",$info);
if ($success == 0) {
    print $pdf2->lastErrorText() . "\r\n";
    exit;
}

print "  saved file: " . $info->stringOf("algorithm") . ", PDF " . $info->stringOf("pdfVersion") . "\r\n";

#  RC4-128, a broken cipher, only for readers too old for AES.  Saved as PDF 1.4.
$pdf3 = chilkat::CkPdf->new();
$success = $pdf3->LoadFile("qa_data/pdf/two_page_memo.pdf");
if ($success == 0) {
    print $pdf3->lastErrorText() . "\r\n";
    exit;
}

$pdf3->put_UserPassword("user-secret");
$pdf3->put_OwnerPassword("owner-secret");
$json->UpdateString("algorithmChoice","rc4-128");
$success = $pdf3->Protection("encrypt",$json,$jsonOut);
if ($success == 0) {
    print $pdf3->lastErrorText() . "\r\n";
    exit;
}

print "rc4-128 will be saved as PDF " . $jsonOut->stringOf("pending.pdfVersion") . "\r\n";
$success = $pdf3->WriteFile("qa_output/memo_rc4_128.pdf");
if ($success == 0) {
    print $pdf3->lastErrorText() . "\r\n";
    exit;
}

$success = $pdf3->PreLoadCheck("qa_output/memo_rc4_128.pdf",$info);
if ($success == 0) {
    print $pdf3->lastErrorText() . "\r\n";
    exit;
}

print "  saved file: " . $info->stringOf("algorithm") . ", PDF " . $info->stringOf("pdfVersion") . "\r\n";

#  Sample output:

#  aes-256 will be saved as PDF 1.7, Adobe extension level 8
#    saved file: aes-256, PDF 1.7
#  aes-128 will be saved as PDF 1.6
#    saved file: aes-128, PDF 1.6
#  rc4-128 will be saved as PDF 1.4
#    saved file: rc4-128, PDF 1.4