Xojo Plugin

RSA Encrypt Bytes to Base64 and Reverse

See more RSA Examples

Demonstrates how to RSA encrypt bytes to base64 and the reverse. Xojo Plugin

Dim success As Boolean
success = 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.
Dim pubKey As New Chilkat.PublicKey
// In all Chilkat methods expecting a path, you pass either absolute or relative paths.
success = pubKey.LoadFromFile("qa_data/rsaKeys/myTestRsaPublic.pem")
If (success = False) Then
    System.DebugLog(pubKey.LastErrorText)
    Return
End If

Dim rsa As New Chilkat.Rsa

// Tell RSA to use the public key.
success = rsa.UsePublicKey(pubKey)

// 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

// A typical use for RSA is to encrypt symmetric encryption keys, such as an AES key.
Dim prng As New Chilkat.Prng
Dim keyBytes As MemoryBlock
keyBytes = prng.GenRandomBytes(32)

rsa.EncodingMode = "base64"
Dim encryptedB64 As String
encryptedB64 = rsa.EncryptBytesENC(keyBytes,False)

System.DebugLog("Result:")
System.DebugLog(encryptedB64)

// Sample output:
// hTTV4Lbmm2V7NCw/HaoJL8Aq/MM/HXblQnjitrF9HY1zBlISwui2jGVVZDtZcZ/rICOpPw44w8Qb8AswFVE1sryydmNEvcIfYAp/xgdBPXBERAS0y4AoEzUfuC5TJmJFvnFkl2lX8GAclANfcTik38V+k3EXu5wPzHKNFb07c6jnwh3Jm4f3PRUhmmB2NO5kSWqHsx0dNglOTq5BUZx34nxlXL5G8d7mXqITsUtrOHXAO/Gb7IrvB81Xk2vc5p4yHhiY/rFTHTTmZyzte2qHGm7V6xPRNURjiivnMY2jQU0Um1JKQcAiSe8Suwvd2LXP5PIhl71VLgO+fokjnynfRg==

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

// Load the matching 2048-bit RSA private key.
Dim privKey As New Chilkat.PrivateKey
Dim password As String
password = "secret"
success = privKey.LoadAnyFormatFile("qa_data/rsaKeys/myTestRsaPrivate.pem",password)
If (success = False) Then
    System.DebugLog(privKey.LastErrorText)
    Return
End If

// Tell the RSA object to use the private key.
success = rsa.UsePrivateKey(privKey)

Dim decBytes As MemoryBlock
decBytes = rsa.DecryptBytesENC(encryptedB64,True)
If (success = False) Then
    System.DebugLog(rsa.LastErrorText)
    Return
End If

System.DebugLog("Success.")