(VB.NET) RSA Sign using Base64 Private Key

Signs a string using a non-encrypted RSA private key in base64 encoding. Returns the RSA signature as a base64 string.

Note: This example requires Chilkat v11.0.0 or greater.

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Dim success As Boolean = False

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

Dim privKey As New Chilkat.PrivateKey

Dim sbPem As New Chilkat.StringBuilder
sbPem.AppendLine("-----BEGIN RSA PRIVATE KEY-----",True)
sbPem.AppendLine("MIIC .... j5A==",True)
sbPem.AppendLine("-----END RSA PRIVATE KEY-----",True)

success = privKey.LoadPem(sbPem.GetAsString())
If (success = False) Then
    Debug.WriteLine(privKey.LastErrorText)
    Exit Sub
End If


Dim rsa As New Chilkat.Rsa

success = rsa.UsePrivateKey(privKey)
If (success = False) Then
    Debug.WriteLine(rsa.LastErrorText)
    Exit Sub
End If


Dim bd As New Chilkat.BinData
bd.AppendString("12345678","utf-8")

success = rsa.SignRawBd(bd)
If (success = False) Then
    Debug.WriteLine(rsa.LastErrorText)
    Exit Sub
End If


' Get the base64 RSA signature.
Debug.WriteLine(bd.GetEncoded("base64"))

success = rsa.VerifyRawBd(bd)
If (success = False) Then
    Debug.WriteLine(rsa.LastErrorText)
    Exit Sub
End If


Dim strOriginal As String = bd.GetString("utf-8")
Debug.WriteLine(strOriginal)