obtener llave privada del certificado

openssl pkcs12 -in certificado.pfx -nocerts -nodes -out certif.pem -password pass:clave

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Transformar de base64 a decimal

 Dim array As Byte() = Convert.FromBase64String("AQAB")
 Dim hex As String = BitConverter.ToString(array).Replace("-", String.Empty)
 Dim n As Integer = Val("&H" & hex)

Dim n1 As Integer = Val("&H" & BitConverter.ToString(Convert.FromBase64String("AQAB")).Replace("-", String.Empty))


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