AutoIt Requires Chilkat v11.0.0+

RSA Encrypt String to Encoded Result and Reverse

See more RSA Examples

Demonstrates how to RSA encrypt a string to a base64 encoded result, and the reverse. AutoIt

Local $bSuccess = False

;  The RSA public key is used for encryption, and the private key for decryption.

;  The public key's role is to make encryption accessible to anyone while ensuring that
;  only the private key holder can decrypt the messages.
;  The public key is designed to be widely distributed so anyone can use it to encrypt messages
;  intended for the owner of the private key.

;  Load our 2048-bit RSA public key.
$oPubKey = ObjCreate("Chilkat.PublicKey")
;  In all Chilkat methods expecting a path, you pass either absolute or relative paths.
$bSuccess = $oPubKey.LoadFromFile("rsaKeys/myTestRsaPublic.pem")
If ($bSuccess = False) Then
    ConsoleWrite($oPubKey.LastErrorText & @CRLF)
    Exit
EndIf

$oRsa = ObjCreate("Chilkat.Rsa")

;  Tell RSA to use the public key.
$oRsa.UsePublicKey($oPubKey)

;  RSA encryption is for small amounts of data, on the order of 200 bytes or less.
;  The maximum number of bytes that can be RSA encrypted depends
;  on the RSA key size and padding scheme (OAEP padding vs PKCS#1 v1.5 padding).
;  For specific limits, see: RSA Encryption Maximum Number of Bytes

;  Encrypt the utf-8 byte representation of the string.
$oRsa.Charset = "utf-8"
$oRsa.EncodingMode = "base64"

;  Be Careful when Using non-us-ascii String Literals in Source Code
Local $sEncryptedB64 = $oRsa.EncryptStringENC("Élève français dîne à côté d’un café où l’on sert déjà du gâteau au chocolat et des éclairs délicieux",False)

;  ------------------------------------------------------------------------------------------------------------------------
;  Let's decrypt, which requires the matching private key...

;  Load the matching 2048-bit RSA private key.
$oPrivKey = ObjCreate("Chilkat.PrivateKey")
Local $sPassword = "secret"
$bSuccess = $oPrivKey.LoadAnyFormatFile("rsaKeys/myTestRsaPrivate.pem",$sPassword)
If ($bSuccess = False) Then
    ConsoleWrite($oPrivKey.LastErrorText & @CRLF)
    Exit
EndIf

;  Tell the RSA object to use the private key.
$oRsa.UsePrivateKey($oPrivKey)

;  Indicate that after decrypting the resultant decrypted bytes contains the utf-8 byte representation of the text.
$oRsa.Charset = "utf-8"
$oRsa.EncodingMode = "base64"
Local $sOriginalText = $oRsa.DecryptStringENC($sEncryptedB64,True)
If ($bSuccess = False) Then
    ConsoleWrite($oRsa.LastErrorText & @CRLF)
    Exit
EndIf

ConsoleWrite("Original text = " & $sOriginalText & @CRLF)
ConsoleWrite("Success." & @CRLF)