PowerShell 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. PowerShell

Add-Type -Path "C:\chilkat\ChilkatDotNet47-x64\ChilkatDotNet47.dll"

$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

$json = New-Object Chilkat.JsonObject
$jsonOut = New-Object Chilkat.JsonObject
$info = New-Object Chilkat.JsonObject

#  AES-256, the default.  Saved as PDF 1.7 with Adobe extension level 8.
$pdf1 = New-Object Chilkat.Pdf
$success = $pdf1.LoadFile("qa_data/pdf/two_page_memo.pdf")
if ($success -eq $false) {
    $($pdf1.LastErrorText)
    exit
}

$pdf1.UserPassword = "user-secret"
$pdf1.OwnerPassword = "owner-secret"
$json.UpdateString("algorithmChoice","aes-256")
$success = $pdf1.Protection("encrypt",$json,$jsonOut)
if ($success -eq $false) {
    $($pdf1.LastErrorText)
    exit
}

$("aes-256 will be saved as PDF " + $jsonOut.StringOf("pending.pdfVersion") + ", Adobe extension level " + $jsonOut.IntOf("pending.adobeExtensionLevel"))
$success = $pdf1.WriteFile("qa_output/memo_aes256.pdf")
if ($success -eq $false) {
    $($pdf1.LastErrorText)
    exit
}

$success = $pdf1.PreLoadCheck("qa_output/memo_aes256.pdf",$info)
if ($success -eq $false) {
    $($pdf1.LastErrorText)
    exit
}

$("  saved file: " + $info.StringOf("algorithm") + ", PDF " + $info.StringOf("pdfVersion"))

#  AES-128, for readers that predate AES-256.  Saved as PDF 1.6.
$pdf2 = New-Object Chilkat.Pdf
$success = $pdf2.LoadFile("qa_data/pdf/two_page_memo.pdf")
if ($success -eq $false) {
    $($pdf2.LastErrorText)
    exit
}

$pdf2.UserPassword = "user-secret"
$pdf2.OwnerPassword = "owner-secret"
$json.UpdateString("algorithmChoice","aes-128")
$success = $pdf2.Protection("encrypt",$json,$jsonOut)
if ($success -eq $false) {
    $($pdf2.LastErrorText)
    exit
}

$("aes-128 will be saved as PDF " + $jsonOut.StringOf("pending.pdfVersion"))
$success = $pdf2.WriteFile("qa_output/memo_aes128.pdf")
if ($success -eq $false) {
    $($pdf2.LastErrorText)
    exit
}

$success = $pdf2.PreLoadCheck("qa_output/memo_aes128.pdf",$info)
if ($success -eq $false) {
    $($pdf2.LastErrorText)
    exit
}

$("  saved file: " + $info.StringOf("algorithm") + ", PDF " + $info.StringOf("pdfVersion"))

#  RC4-128, a broken cipher, only for readers too old for AES.  Saved as PDF 1.4.
$pdf3 = New-Object Chilkat.Pdf
$success = $pdf3.LoadFile("qa_data/pdf/two_page_memo.pdf")
if ($success -eq $false) {
    $($pdf3.LastErrorText)
    exit
}

$pdf3.UserPassword = "user-secret"
$pdf3.OwnerPassword = "owner-secret"
$json.UpdateString("algorithmChoice","rc4-128")
$success = $pdf3.Protection("encrypt",$json,$jsonOut)
if ($success -eq $false) {
    $($pdf3.LastErrorText)
    exit
}

$("rc4-128 will be saved as PDF " + $jsonOut.StringOf("pending.pdfVersion"))
$success = $pdf3.WriteFile("qa_output/memo_rc4_128.pdf")
if ($success -eq $false) {
    $($pdf3.LastErrorText)
    exit
}

$success = $pdf3.PreLoadCheck("qa_output/memo_rc4_128.pdf",$info)
if ($success -eq $false) {
    $($pdf3.LastErrorText)
    exit
}

$("  saved file: " + $info.StringOf("algorithm") + ", PDF " + $info.StringOf("pdfVersion"))

#  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