(VBScript) RSA Encrypt Randomly Generated AES Key

Demonstrates how to RSA encrypt a randomly generated AES key.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

Dim fso, outFile
Set fso = CreateObject("Scripting.FileSystemObject")
'Create a Unicode (utf-16) output text file.
Set outFile = fso.CreateTextFile("output.txt", True, True)

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

' First generate a 256-bit AES key (32 bytes).
' For versions of Chilkat < 10.0.0, use CreateObject("Chilkat_9_5_0.Prng")
set prng = CreateObject("Chilkat.Prng")
' For versions of Chilkat < 10.0.0, use CreateObject("Chilkat_9_5_0.BinData")
set bdAesKey = CreateObject("Chilkat.BinData")
success = prng.GenRandomBd(32,bdAesKey)

' Use a public key from a certificate for RSA encryption.
' For versions of Chilkat < 10.0.0, use CreateObject("Chilkat_9_5_0.Cert")
set cert = CreateObject("Chilkat.Cert")

success = cert.LoadFromFile("qa_data/pem/mf_public_rsa.pem")
If (success = 0) Then
    outFile.WriteLine(cert.LastErrorText)
    WScript.Quit
End If

' pubKey is a Chilkat.PublicKey
Set pubKey = cert.ExportPublicKey()
If (cert.LastMethodSuccess <> 1) Then
    outFile.WriteLine(cert.LastErrorText)
    WScript.Quit
End If

' For versions of Chilkat < 10.0.0, use CreateObject("Chilkat_9_5_0.Rsa")
set rsa = CreateObject("Chilkat.Rsa")
success = rsa.ImportPublicKeyObj(pubKey)
If (success = 0) Then
    outFile.WriteLine(rsa.LastErrorText)
    WScript.Quit
End If

' RSA encrypt our 32-byte AES key.
' The contents of bdAesKey are replaced with result of the RSA encryption.
success = rsa.EncryptBd(bdAesKey,0)
If (success = 0) Then
    outFile.WriteLine(rsa.LastErrorText)
    WScript.Quit
End If

' Return the result as a base64 string
encryptedAesKey = bdAesKey.GetEncoded("base64")

outFile.WriteLine("encrypted AES key = " & encryptedAesKey)

outFile.Close