(VBScript) RSA Signature with Certificate's Private Key from PFX

Demonstrates how to use a certificate's private key from a PFX file to create an RSA signature.

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

Dim fso, outFile
Set fso = CreateObject("Scripting.FileSystemObject")
Set outFile = fso.CreateTextFile("output.txt", True)

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

' Create an instance of a certificate store object, load a PFX file,
' locate the certificate we need, and use it for signing.
' (a PFX file may contain more than one certificate.)
set certStore = CreateObject("Chilkat_9_5_0.CertStore")

' The 1st argument is the filename, the 2nd arg is the 
' PFX file's password:
success = certStore.LoadPfxFile("chilkat.pfx","test")
If (success <> 1) Then
    outFile.WriteLine(certStore.LastErrorText)
    WScript.Quit
End If

' cert is a Chilkat_9_5_0.Cert
Set cert = certStore.FindCertBySubject("Chilkat Software, Inc.")
If (certStore.LastMethodSuccess = 0) Then
    outFile.WriteLine(certStore.LastErrorText)
    WScript.Quit
End If

' pkey is a Chilkat_9_5_0.PrivateKey
Set pkey = cert.ExportPrivateKey()
If (cert.LastMethodSuccess = 0) Then
    outFile.WriteLine(cert.LastErrorText)

    WScript.Quit
End If

' Get the private key in XML format:
pkeyXml = pkey.GetXml()

set rsa = CreateObject("Chilkat_9_5_0.Rsa")

' Import the private key into the RSA component:
success = rsa.ImportPrivateKey(pkeyXml)
If (success <> 1) Then
    outFile.WriteLine(rsa.LastErrorText)

    WScript.Quit
End If

' This example will sign a string, and receive the signature
' in a hex-encoded string.  Therefore, set the encoding mode
' to "hex":
rsa.EncodingMode = "hex"

' If some other non-Chilkat application or web service is going to be verifying
' the signature, it is important to match the byte-ordering.
' The LittleEndian property may be set to 1
' for little-endian byte ordering, 
' or 0  for big-endian byte ordering.
' Microsoft apps typically use little-endian, while
' OpenSSL and other services (such as Amazon CloudFront)
' use big-endian.
rsa.LittleEndian = 0

strData = "This is the string to be signed."

' Sign the string using the sha-1 hash algorithm.
' Other valid choices are "sha-256", "md2" and "md5".
hexSig = rsa.SignStringENC(strData,"sha-1")

outFile.WriteLine(hexSig)

outFile.WriteLine("Success!")

outFile.Close