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Xojo Plugin Requires Chilkat v11.0.0+

RSA Encrypt and Decrypt Credit Card Numbers

See more RSA Examples

_LANGUAGE_ sample code to RSA public-key encrypt and decrypt credit card numbers. The RSA key is loaded from an unencrypted PKCS8 file. Chilkat provides many ways of setting the key -- loading from both encrypted and unencrypted PEM, PKCS8, DER, PVK, etc. Keys may be loaded from files or in-memory representations. (The RSA component also provides the ability to generate RSA keys.)

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Xojo Plugin
Dim success As Boolean
success = False

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

Dim rsa As New Chilkat.Rsa

Dim privKey As New Chilkat.PrivateKey

//  Load an RSA private key from a file:
success = privKey.LoadAnyFormatFile("rsaPrivateKey.key","")
If (success = False) Then
    System.DebugLog(privKey.LastErrorText)
    Return
End If

//  Get the public part of the private key.
Dim pubKey As New Chilkat.PublicKey
success = privKey.ToPublicKey(pubKey)

success = rsa.UsePublicKey(pubKey)
If (success = False) Then
    System.DebugLog(rsa.LastErrorText)
    Return
End If

//  Encrypt a VISA credit card number:
//  1234-5678-0000-9999
Dim ccNumber As String
ccNumber = "1234567800009999"

Dim usePrivateKey As Boolean
usePrivateKey = False
rsa.EncodingMode = "base64"
Dim encryptedStr As String
encryptedStr = rsa.EncryptStringENC(ccNumber,usePrivateKey)
System.DebugLog("Encrypted:")
System.DebugLog(encryptedStr)

//  Now decrypt:
Dim rsaDecryptor As New Chilkat.Rsa

rsaDecryptor.EncodingMode = "base64"
success = rsaDecryptor.UsePrivateKey(privKey)

usePrivateKey = True
Dim decryptedStr As String
decryptedStr = rsaDecryptor.DecryptStringENC(encryptedStr,usePrivateKey)

System.DebugLog("Decrypted:")
System.DebugLog(decryptedStr)

//  Important: RSA encryption should only be used to encrypt small amounts of data.
//  It is typically used for encrypting symmetric encryption
//  keys such that a symmetric encryption algorithm, such as 
//  AES is then used to encrypt/decrypt bulk data.