(PowerShell) Sign JSON to Create CAdES P7S Bytes

Demonstrates how to sign JSON using a certificate + private key from a .p12/.pfx to create a CAdES P7S byte array.

Chilkat .NET Downloads Chilkat .NET Assemblies

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

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

$crypt = New-Object Chilkat.Crypt2

$cert = New-Object Chilkat.Cert
$success = $cert.LoadPfxFile("qa_data/pfx/cert_test123.pfx","test123")
if ($success -ne $true) {
    $($cert.LastErrorText)
    exit
}

# Tell the crypt component to use this cert.
$success = $crypt.SetSigningCert($cert)
if ($success -ne $true) {
    $($crypt.LastErrorText)
    exit
}

# The CadesEnabled property applies to all methods that create PKCS7 signatures. 
# To create a CAdES-BES signature, set this property equal to true. 
$crypt.CadesEnabled = $true

$crypt.HashAlgorithm = "sha256"

$jsonSigningAttrs = New-Object Chilkat.JsonObject
$jsonSigningAttrs.UpdateInt("contentType",1)
$jsonSigningAttrs.UpdateInt("signingTime",1)
$jsonSigningAttrs.UpdateInt("messageDigest",1)
$jsonSigningAttrs.UpdateInt("signingCertificateV2",1)
$crypt.SigningAttributes = $jsonSigningAttrs.Emit()

# By default, all the certs in the chain of authentication are included in the signature.
# If desired, we can choose to only include the signing certificate:
$crypt.IncludeCertChain = $false

# Create the CAdES-BES attached signature, which contains the original data.
$crypt.Charset = "utf-8"

$cadesP7s = $crypt.OpaqueSignString("{ `"abc`": 123}")
if ($crypt.LastMethodSuccess -eq $false) {
    $($crypt.LastErrorText)
    exit
}

# Verify the signature and extract the original JSON:
$originalJson = $crypt.OpaqueVerifyString($cadesP7s)
if ($crypt.LastMethodSuccess -eq $false) {
    $($crypt.LastErrorText)
    exit
}

$("Original JSON: " + $originalJson)

$("Success!")