(PowerShell) Create CMS (PKCS7) Detached MIME Signature

Demonstrates how to add a CMS detached signature to MIME.

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.

$mime = New-Object Chilkat.Mime

# Load a certificate w/ private key for signing.
$cert = New-Object Chilkat.Cert
$success = $cert.LoadPfxFile("qa_data/pfx/ecc256_12345.p12","12345")
if ($success -ne $true) {
    $($cert.LastErrorText)
    exit
}

$("Cert: " + $cert.SubjectDN)

# Create a simple MIME message to be signed:
$mime.AddHeaderField("Subject","This is a test")
$mime.AddHeaderField("MyCustomHeader","abc123")
$mime.ContentType = "text/plain"
$mime.SetBody("This is a plain-text body.")

# Examine the MIME prior to signing:
$("--- MIME prior to signing ---")
$($mime.GetMime())

# The MIME prior to signing looks like this:

# Subject: This is a test
# MyCustomHeader: abc123
# Content-Type: text/plain; format=flowed
# 
# This is a plain-text body.

# Use SHA256 as the hash algorithm in the CMS signature.
$mime.SigningHashAlg = "SHA256"

# Add a detached signature:
$success = $mime.AddDetachedSignature($cert)
if ($success -eq $false) {
    $($mime.LastErrorText)
    exit
}

# Examine the MIME with detached signature:
$("--- MIME with detached signature ---")
$($mime.GetMime())

# Content-Type: multipart/signed; boundary="----=_NextPart_6e3_c655_9641494d.b4f00501";
#  protocol="application/x-pkcs7-signature";
#  micalg=sha256
# 
# ------=_NextPart_6e3_c655_9641494d.b4f00501
# Subject: This is a test
# MyCustomHeader: abc123
# Content-Type: text/plain; format=flowed
# 
# This is a plain-text body.
# ------=_NextPart_6e3_c655_9641494d.b4f00501
# Content-Transfer-Encoding: base64
# Content-Type: application/x-pkcs7-signature; name="smime.p7s"
# Content-Disposition: attachment; filename="smime.p7s"
# 
# MIID7AYJKoZIhvcNAQcCoIID3TCCA9kCAQExDzANBglghkgBZQMEAgEFADALBgkqhkiG9w0BBwGg
# ggJxMIICbTCCAhOgAwIBAgIJAJuS2kgOoyr+MAkGByqGSM49BAEwWzELMAkGA1UEBhMCQVUxEzAR
# BgNVBAgTClNvbWUtU3RhdGUxITAfBgNVBAoTGEludGVybmV0IFdpZGdpdHMgUHR5IEx0ZDEUMBIG
# A1UEAxMLZWNjMjU2LXRlc3QwHhcNMTYwODIzMTU0OTM5WhcNNDQwMTA4MTU0OTM5WjBbMQswCQYD
# VQQGEwJBVTETMBEGA1UECBMKU29tZS1TdGF0ZTEhMB8GA1UEChMYSW50ZXJuZXQgV2lkZ2l0cyBQ
# dHkgTHRkMRQwEgYDVQQDEwtlY2MyNTYtdGVzdDBZMBMGByqGSM49AgEGCCqGSM49AwEHA0IABARy
# Hd86A7+qQ4DlIfKynZaFGdGLpkU3GlQwqaVD6GIJg3QIDhaWEksYtZ9OWjNHn9a6+i/P9o5/NrdI
# SP0VWDWjgcAwgb0wHQYDVR0OBBYEFGmd2DfK4c3VBTVn8ebKH2BTmRicMIGNBgNVHSMEgYUwgYKA
# FGmd2DfK4c3VBTVn8ebKH2BTmRicoV+kXTBbMQswCQYDVQQGEwJBVTETMBEGA1UECBMKU29tZS1T
# dGF0ZTEhMB8GA1UEChMYSW50ZXJuZXQgV2lkZ2l0cyBQdHkgTHRkMRQwEgYDVQQDEwtlY2MyNTYt
# dGVzdIIJAJuS2kgOoyr+MAwGA1UdEwQFMAMBAf8wCQYHKoZIzj0EAQNJADBGAiEAhuiwGy0lZKtK
# LA13Ffc8AMTK7NsePPSfs0clXlZUR78CIQDXsJXpYsJ7tlTeockrK+6099sG/gGFTRPiQYU8juyf
# LzGCAT8wggE7AgEBMGgwWzELMAkGA1UEBhMCQVUxEzARBgNVBAgTClNvbWUtU3RhdGUxITAfBgNV
# BAoTGEludGVybmV0IFdpZGdpdHMgUHR5IEx0ZDEUMBIGA1UEAxMLZWNjMjU2LXRlc3QCCQCbktpI
# DqMq/jANBglghkgBZQMEAgEFAKBpMBgGCSqGSIb3DQEJAzELBgkqhkiG9w0BBwEwHAYJKoZIhvcN
# AQkFMQ8XDTIyMDUwODE0MzM1NFowLwYJKoZIhvcNAQkEMSIEIMvNpYuymLvF68aFFe+l3NEQTdkB
# 7T8U6/j+Y5FgDlIUMAoGCCqGSM49BAMCBEYwRAIgQ6migEn3Le9ciIVUP/qc2JZAJZWjpulJXY9Q
# IZJ3XK0CIGZwpLOgiv7ES8958hqT9a/q7aPc1xmkaZHtsat/k+Ki
# 
# ------=_NextPart_6e3_c655_9641494d.b4f00501--