PowerShell

openssl smime -encrypt -des3 -in <file> <pem file>

See more OpenSSL Examples

OpenSSL SMIME encrypt file using PEM containing a certificate. 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.

# Load the cert from a PEM file.

$pem = New-Object Chilkat.Pem
# Our particular PEM was not encrypted, so we pass an empty password.
# Also, a private key is not needed for encryption.  The PEM used to test this example
# happens to have a private key, but it's not actually used.
$success = $pem.LoadPemFile("qa_data/openssl/rsaCertAndKey.pem","")
if ($success -eq $false) {
    $($pem.LastErrorText)
    exit
}

if ($pem.NumCerts -eq 0) {
    $("PEM does not contain any certificates.")
    exit
}

$cert = $pem.GetCert(0)
if ($pem.LastMethodSuccess -eq $false) {
    $($pem.LastErrorText)
    exit
}

# -------------------------------------------------------------------------------------
# Duplicate this OpenSSL command:   openssl smime -encrypt -des3 -in <file> <pem file>
# -------------------------------------------------------------------------------------
$crypt = New-Object Chilkat.Crypt2
$success = $crypt.SetEncryptCert($cert)
if ($success -eq $false) {
    $($crypt.LastErrorText)

    exit
}

$crypt.CryptAlgorithm = "PKI"
$crypt.Pkcs7CryptAlg = "3des"
$crypt.KeyLength = 168

# Load the file to be encrypted.
$bd = New-Object Chilkat.BinData
$success = $bd.LoadFile("qa_data/openssl/hello.txt")
if ($success -eq $false) {
    $("Failed to load the input file.")
    exit
}

# Encrypt.
$success = $crypt.EncryptBd($bd)
if ($success -eq $false) {
    $($crypt.LastErrorText)
    exit
}

# The openssl smime -encrypt command produces encrypte MIME such as this:

# MIME-Version: 1.0
# Content-Disposition: attachment; filename="smime.p7m"
# Content-Type: application/x-pkcs7-mime; smime-type=enveloped-data; name="smime.p7m"
# Content-Transfer-Encoding: base64
# 
# MIICzwYJKoZIhvcNAQcDoIICwDCCArwCAQAxggF8MIIBeAIBADBgMEoxCzAJBgNVBAYTAlVTMRYw
# FAYDVQQKEw1MZXQncyBFbmNyeXB0MSMwIQYDVQQDExpMZXQncyBFbmNyeXB0IEF1dGhvcml0eSBY
# MwISA9Nqgb1dH/XTDNeKzN1nR85iMA0GCSqGSIb3DQEBAQUABIIBAIQqPexjxWovgxwKV/r3HL/U
# EP9Yozvz5hBeX5VvRZjKSi4FRw5wapElPK+4FB82hiAR9Mi3c16PvPSVkJv3l78Mv5uaaOs/OmUz
# mIHFB6Z+l2E52BDmUVWJZTQ09vdWy6+NIRlg2R9Z1NkmZ4BZCJk6mHB/Yx03IaOxK8LnwieDMthM
# SvxbhJnIOISN7k7ofs+/0vTXUpdQ+tlmwyVySMGQ6VMk+z4sqZJ2stacqCPtt/aiSwJ9p0OKmihf
# 3KDJceXJtavIQeA97yz1LqPvle35mmd5sBhV9qQYdTV/KJ+YM5uEZ9BHYbvMJbADFHwKzhcEY3qA
# 7T9acmEsb7NycOIwggE1BgkqhkiG9w0BBwEwFAYIKoZIhvcNAwcECERX/ZoHweSkgIIBEMmCMx49
# zjVAnGqRaBbvzQT1hg0uQSxIJjxMxC+HSuM+eY9oSOsbrw4uIijHKH9NdOpeDsdRzg2z5EBM7AlP
# Ht9DyPW5C2deV6RPX4F8gyExz+JUXrd+3Yb3AKTdpDkTWDmNCeO0r/YSqp518+mfU5hG8e336u51
# HAM44FeknA8oThWsD/wUB1e8vzsatK4UXW/KSu/166V7z+VT86kd+IHa7t60U9Yp0ZXgcM5Pb5Ni
# 69Qc5MKPzom2801H5UR/WjCgsxOIjOj49sKisjRy79skrJzxY5ZG05T0dKn6KC3TjRpIEEeOyhCd
# Nm2Y7dcW8GLMepdhWay5vePmQxmvmhbAtBprIem14NcrYeG6D5wP

# We have the body in bd
# Construct the header and base64 body...
$sbEncryptedMime = New-Object Chilkat.StringBuilder

$sbEncryptedMime.AppendLine("MIME-Version: 1.0",$true)
$sbEncryptedMime.AppendLine("Content-Disposition: attachment; filename=`"smime.p7m`"",$true)
$sbEncryptedMime.AppendLine("Content-Type: application/x-pkcs7-mime; smime-type=enveloped-data; name=`"smime.p7m`"",$true)
$sbEncryptedMime.AppendLine("Content-Transfer-Encoding: base64",$true)
$sbEncryptedMime.AppendLine("",$true)
$sbEncryptedMime.AppendLine($bd.GetEncoded("base64_mime"),$true)

# Show the result.
$($sbEncryptedMime.GetAsString())

# or save to a file..
$success = $sbEncryptedMime.WriteFile("qa_output/encryptedMime.txt","utf-8",$false)