Salve a tutti.
Ho trovato un modo per cryptareuna stringa con l'algoritmo sha512:

codice:
    Public Function CriptaStringa(ByVal Str As String)
        'Aloritmo SHA512
        Dim Vet() As Byte

        Dim hash As String = ""
        Dim bb As Byte() = System.Text.Encoding.Default.GetBytes(Str)
        Dim sha As New System.Security.Cryptography.SHA512Managed()
        Dim enc As Byte() = sha.TransformFinalBlock(bb, 0, bb.Length)
        Dim b As Byte
        For Each b In sha.Hash
            hash += Convert.ToString(b, 16).ToUpper().PadLeft(2, "0")
            sha.Clear()
        Next
        Return hash
    End Function
ora però dovrei decriptare questa stringa...come si procede?