(PowerShell) AES Encrypt String (utf-8 byte representation) and return Base64

Demonstrates how to AES encrypt the utf-8 byte representation of a string and return in base64 format.

Chilkat .NET Downloads Chilkat .NET Assemblies

Add-Type -Path "C:\chilkat\ChilkatDotNet47-9.5.0-x64\ChilkatDotNet47.dll"

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

$crypt = New-Object Chilkat.Crypt2

$crypt.CryptAlgorithm = "aes"
$crypt.CipherMode = "cbc"
$crypt.KeyLength = 256
$crypt.Charset = "utf-8"
$crypt.EncodingMode = "base64"

$ivHex = "000102030405060708090A0B0C0D0E0F"
$crypt.SetEncodedIV($ivHex,"hex")
$keyHex = "000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F"
$crypt.SetEncodedKey($keyHex,"hex")

$encryptedStr = $crypt.EncryptStringENC("This is the original string")
$($encryptedStr)

# Let's say we want to URL encode the base64 string..
$crypt.CryptAlgorithm = "none"
$crypt.EncodingMode = "url"
$urlEncoded = $crypt.EncryptStringENC($encryptedStr)
$($urlEncoded)

# Sample output:

#  q3fmgEqjqa9o//ZS6aPuh4Wtbrrxx/WOIQSKeVnesZg=
#  q3fmgEqjqa9o%2F%2FZS6aPuh4Wtbrrxx%2FWOIQSKeVnesZg%3D

# -------------------------------------------------------------------
# Now let's do the reverse...
# 

# We start with a string that is the binary encrypted data, base64 encoded, and then URL encoded.
$encBase64Url = "q3fmgEqjqa9o%2F%2FZS6aPuh4Wtbrrxx%2FWOIQSKeVnesZg%3D"

# We'll use the same crypt object.  If using a new instance of the crypt object,
# make sure *all* settings are identical:  the algorithm, cipher mode, key length, charset, encoding mode, IV, and secret key.

# Decode from URL...
$crypt.CryptAlgorithm = "none"
$crypt.EncodingMode = "url"
$encBase64 = $crypt.DecryptStringENC($urlEncoded)
$($encBase64)

# Now decrypt...
$crypt.CryptAlgorithm = "aes"
$crypt.EncodingMode = "base64"
$originalStr = $crypt.DecryptStringENC($encBase64)
$($originalStr)