(PowerShell) Extract XML string from a .p7m byte array (e.g. FATTURA ELETTRONICA, ITALY)

PowerShell example to extract the original XML from a .p7m (Signed-Data PKCS7 Format) provided as a byte array.

One use for this example is to extract the original XML from a Fattura Elettronica .p7m signature.

Chilkat .NET Downloads Chilkat .NET Assemblies

Add-Type -Path "C:\chilkat\ChilkatDotNet47-9.5.0-x64\ChilkatDotNet47.dll"

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

$fac = New-Object Chilkat.FileAccess

$p7mBytes = $fac.ReadEntireFile("testData/p7m/fattura_signature.p7m")
if ($fac.LastMethodSuccess -ne $true) {
    $($fac.LastErrorText)
    exit
}

$crypt = New-Object Chilkat.Crypt2

$originalXml = $crypt.OpaqueVerifyString($p7mBytes)
if ($crypt.LastMethodSuccess -ne $true) {
    $($fac.LastErrorText)
    exit
}

$("Original XML:")
$($originalXml)

$("Success!")