(PowerShell) RSA Encrypt RSA/ECB/OAEPWithSHA1AndMGF1Padding

Demonstrates how to RSA encrypt using RSA/ECB/OAEPWithSHA1AndMGF1Padding. Also demonstrates RSA/ECB/OAEPWithSHA-256AndMGF1Padding. Both of these terms are from Java's JCE. Note: In this context, "ECB" doesn't actually mean anything. It's a symmetric cipher mode that doesn't apply (or make sense) in this context.

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.

$rsa = New-Object Chilkat.Rsa

# First load a public key object with a public key.
# In this case, we'll load it from a file.
$pubkey = New-Object Chilkat.PublicKey
$success = $pubkey.LoadFromFile("qa_data/pem/rsa_public.pem")
if ($success -ne $true) {
    $($pubkey.LastErrorText)
    exit
}

# RSA encryption is limited to small amounts of data. The limit
# is typically a few hundred bytes and is based on the key size and
# padding (OAEP vs. PKCS1_5).  RSA encryption is typically used for
# encrypting hashes or symmetric (bulk encryption algorithm) secret keys.
$plainText = "Time is an illusion. Lunchtime doubly so."

# Import the public key to be used for encrypting.
$success = $rsa.ImportPublicKeyObj($pubkey)

# To get OAEP padding, set the OaepPadding property:
$rsa.OaepPadding = $true

# To use SHA1 or SHA-256, set the OaepHash property
$rsa.OaepHash = "sha256"
# for SHA1 --
$rsa.OaepHash = "sha1"

# Indicate we'll want hex output
$rsa.EncodingMode = "hex"

# Encrypt..
$usePrivateKey = $false
$encryptedStr = $rsa.EncryptStringENC($plainText,$usePrivateKey)
$($encryptedStr)

# -------------------------------------------------
# Now decrypt with the matching private key.
$rsa2 = New-Object Chilkat.Rsa

$privKey = New-Object Chilkat.PrivateKey
$success = $privKey.LoadEncryptedPem("qa_data/pem/rsa_passwd.pem","passwd")
if ($success -ne $true) {
    $($privKey.LastErrorText)
    exit
}

$success = $rsa2.ImportPrivateKeyObj($privKey)

# Make sure we have the same settings used for encryption.
$rsa2.OaepPadding = $true
$rsa2.EncodingMode = "hex"
$rsa2.OaepHash = "sha1"

$originalStr = $rsa2.DecryptStringENC($encryptedStr,$true)

$($originalStr)