(PowerShell) Create PEM-encoded PKCS#7 Detached Signature

See more Digital Signatures Examples

Chilkat .NET Downloads Chilkat .NET Assemblies

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

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

$cert = New-Object Chilkat.Cert

# Load the cert and private key.
$success = $cert.LoadPfxFile("qa_data/pfx/myCertAndKey.p12","password")
if ($success -ne $true) {
    $($cert.LastErrorText)
    exit
}

$crypt = New-Object Chilkat.Crypt2

$success = $crypt.SetSigningCert($cert)
if ($success -ne $true) {
    $($crypt.LastErrorText)
    exit
}

# Use SHA-256
$crypt.HashAlgorithm = "sha256"

# Hash the utf-8 byte representation of the string
$crypt.Charset = "utf-8"

# Return the result in base64
$crypt.EncodingMode = "base64Mime"

# Sign some text to create a detached signature (i.e. a signature that does not include the signed data)
$textToSign = "This is the text to be hashed and signed."
$sigBase64 = $crypt.SignStringENC($textToSign)
if ($crypt.LastMethodSuccess -ne $true) {
    $($crypt.LastErrorText)
    exit
}

$($sigBase64)

# The result:

# MIIWbgYJKoZIhvcNAQcCoIIWXzCCFlsCAQExDzANBglghkgBZQMEAgEFADALBgkqhkiG9w0BBwGg
# ghMXMIIFuzCCA6OgAwIBAgIIVwoRl0LE48wwDQYJKoZIhvcNAQELBQAwazELMAkGA1UEBhMCSVQx
# ...
# ...

# If we want it in PEM format with just LF line-endings:
$sb = New-Object Chilkat.StringBuilder
# Just LF line endings, not CRLF.
$crlf = $false
$sb.AppendLine("-----BEGIN PKCS7-----",$crlf)
$sb.Append($sigBase64)
$sb.AppendLine("-----END PKCS7-----",$crlf)
$sb.ToLF()

# Save to a file.
$sb.WriteFile("c:/temp/qa_output/sig.pem","utf-8",$false)

# Examine..
$($sb.GetAsString())

# Result is:

# -----BEGIN PKCS7-----
# MIIWbgYJKoZIhvcNAQcCoIIWXzCCFlsCAQExDzANBglghkgBZQMEAgEFADALBgkqhkiG9w0BBwGg
# ghMXMIIFuzCCA6OgAwIBAgIIVwoRl0LE48wwDQYJKoZIhvcNAQELBQAwazELMAkGA1UEBhMCSVQx
# DjAMBgNVBAcMBU1pbGFuMSMwIQYDVQQKDBpBY3RhbGlzIFMucC5BLi8wMzM1ODUyMDk2NzEnMCUG
# A1UEAwweQWN0YWxpcyBBdXRoZW50aWNhdGlvbiBSb290IENBMB4XDTExMDkyMjExMjIwMloXDTMw
# MDkyMjExMjIwMlowazELMAkGA1UEBhMCSVQxDjAMBgNVBAcMBU1pbGFuMSMwIQYDVQQKDBpBY3Rh
# bGlzIFMucC5BLi8wMzM1ODUyMDk2NzEnMCUGA1UEAwweQWN0YWxpcyBBdXRoZW50aWNhdGlvbiBS
# b290IENBMIICIjANBgkqhkiG9w0BAQEFAAOCAg8AMIICCgKCAgEAp8bEpSmkLO/lGMWwUKNvUTuf
# ClrJwkg4CsIcoBh/kbWHuUA/3R1oHwiD1S0eiKD4j1aPbZkCkpAW1V8IbInX4ay8IMKx4INRimlN
# AJZaby/ARH6jDuSRzVju3PvHHkVH3Se5CAGfpiEd9UEtL0z9KK3giq0itFZljoZUj5NDKd45Rnij
# MCO6zfB9E1fAXdKDa0hMxKufgFpbOr3JpyI/gCczWw63igxdBzcIy2zSekciRDXFzMwujt0q7bd9
# ...
# ...
# -----END PKCS7-----