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Yubikey RSA Encrypt/Decrypt

See more RSA Examples

Demonstrates how to do RSA decryption using a private key stored on a Yubikey (or other USB token or smartcard).

Note: RSA encryption uses the public key, which is freely exportable and does not need to occur on the token/smartcard.

Chilkat PowerShell Downloads

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

$success = $false

# This example assumes you have a certificate with private key on the Yubikey token.
# When doing simple RSA encryption/decryption, we don't actually need the certificate,
# but we'll be using the private key associated with the certificate.
# 
# The sensitive/secret material that needs to be kept private is the private key.
# The certificate itself and the public key can be freely shared.
# 

# We're going to encrypt and decrypt 32-bytes of data.
$bd = New-Object Chilkat.BinData
$success = $bd.AppendEncoded("000102030405060708090A0B0C0D0E0F","hex")
$success = $bd.AppendEncoded("000102030405060708090A0B0C0D0E0F","hex")

# Let's get the desired cert.
# For this example, a self-signed certificate with a 2048-bit RSA key was generated in slot 9A.
$cert = New-Object Chilkat.Cert

# Force Chilkat to use PKCS11 over ScMinidriver (if on Windows) and Apple Keychain (if on MacOS)
$cert.UncommonOptions = "NoScMinidriver,NoAppleKeychain"

$cert.SmartCardPin = "123456"

$success = $cert.LoadFromSmartcard("cn=chilkat_test_2048")
if ($success -eq $false) {
    $($cert.LastErrorText)
    exit
}

# RSA encrypt using the public key.
$rsa = New-Object Chilkat.Rsa

# Provide the RSA object with the certificate on the Yubkey.
$success = $rsa.SetX509Cert($cert,$true)
if ($success -eq $false) {
    $($rsa.LastErrorText)
    exit
}

# RSA encrypt using the public key.
$usePrivateKey = $false
$success = $rsa.EncryptBd($bd,$usePrivateKey)
if ($success -eq $false) {
    $($rsa.LastErrorText)
    exit
}

$("RSA Encrypted Output in Hex:")
$($bd.GetEncoded("hex"))

# Now let's decrypt, using the private key on the Yubikey.
$usePrivateKey = $true
$success = $rsa.DecryptBd($bd,$usePrivateKey)
if ($success -eq $false) {
    $($rsa.LastErrorText)
    exit
}

$("RSA Decrypted Output in Hex:")
$($bd.GetEncoded("hex"))