PowerShell

SSH Authenticate using a Smart Card Private Key

Demonstrates using a private key stored on an HSM (smart card or token) for SSH public-key authentication. A JSON template locates the private and public key objects by class, key type, and label, and the returned handles are bound to an SshKey object.

Background: PKCS#11 objects are found by attribute rather than by name alone, which is why a template describing the class, key type, and label is used. An important practical detail is that the returned handles are valid only for the lifetime of the PKCS#11 session — they cannot be cached and reused later, so a subsequent session must locate the objects again. Logging out and closing the session when finished releases the device for other applications.

Chilkat PowerShell Downloads

Download Chilkat for PowerShell

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.

#  Demonstrates using a private key stored on an HSM (smart card or token) for SSH public-key
#  authentication.  Public-key authentication means the client uses the private key, while the
#  corresponding public key is installed on the server under the SSH account.
#  
#  Note: Chilkat's PKCS#11 implementation runs on Windows, Linux, macOS, and other supported
#  operating systems.

$pkcs11 = New-Object Chilkat.Pkcs11

#  Use the PKCS#11 driver (.dll, .so, or .dylib) for your particular HSM.
$pkcs11.SharedLibPath = "C:/Program Files (x86)/Gemalto/IDGo 800 PKCS#11/IDPrimePKCS11.dll"

#  The HSM PIN should come from a secure source rather than being hard-coded.
$pin = "0000"

#  Normal user = 1
$userType = 1

$success = $pkcs11.QuickSession($userType,$pin)
if ($success -eq $false) {
    $($pkcs11.LastErrorText)
    exit
}

#  Provide a template describing the PKCS#11 object to find: an RSA private key labeled
#  "MySshKey".  For how such a key is originally imported, see
#  PKCS11 Import SSH Key
$jsonTemplate = New-Object Chilkat.JsonObject
$jsonTemplate.UpdateString("class","private_key")
$jsonTemplate.UpdateString("key_type","rsa")
$jsonTemplate.UpdateString("label","MySshKey")

$privKeyHandle = $pkcs11.FindObject($jsonTemplate)
if ($privKeyHandle -eq 0) {
    $($pkcs11.LastErrorText)
    exit
}

#  The handle is only valid for the duration of this PKCS#11 session.  To use the key in a
#  later session, find it again.
$("private key handle: " + $privKeyHandle)

#  Find the corresponding public key by changing the class in the same template.
$jsonTemplate.UpdateString("class","public_key")

$pubKeyHandle = $pkcs11.FindObject($jsonTemplate)
if ($pubKeyHandle -eq 0) {
    $($pkcs11.LastErrorText)
    exit
}

$("public key handle: " + $pubKeyHandle)

#  Create an empty SSH key object and tell it to use the PKCS#11 handles, indicating the key type.
$sshKey = New-Object Chilkat.SshKey
$success = $sshKey.UsePkcs11($pkcs11,$privKeyHandle,$pubKeyHandle,"rsa")
if ($success -eq $false) {
    $($sshKey.LastErrorText)
    exit
}

$ssh = New-Object Chilkat.Ssh

$port = 22
$success = $ssh.Connect("ssh.example.com",$port)
if ($success -eq $false) {
    $($ssh.LastErrorText)
    exit
}

#  Authentication uses the existing PKCS#11 session.  The signing happens on the smart card --
#  the private key never leaves the device.
$success = $ssh.AuthenticatePk("mySshLogin",$sshKey)
if ($success -eq $false) {
    $($ssh.LastErrorText)
    exit
}

$("Public-key authentication successful.")

#  ... use the authenticated SSH session ...

$ssh.Disconnect()

$pkcs11.Logout()
$pkcs11.CloseSession()