Using FTP TLS 1.2 with FTP

By default most systems allow SSL 3.0, TLS 1.0, 1.2 and 1.2 to be used.

TLS 1.2 is the most secure version of SSL/TLS protocols. It is easy to force the connection to use it. All you need to do is to set Ftp.SSLConfiguration.EnabledSslProtocols property to SslProtocols.Tls12:

// C#

using (Ftp ftp = new Ftp())
{
    ftp.SSLConfiguration.EnabledSslProtocols = SslProtocols.Tls12;

    ftp.ConnectSSL("ftps.example.com");

    ftp.Login("user","password");

    ftp.ChangeFolder("uploads");
    ftp.Upload("report.txt", @"c:\report.txt");


    ftp.Close();
}

' VB.NET

Using ftp As New Ftp()
	ftp.SSLConfiguration.EnabledSslProtocols = SslProtocols.Tls12

	ftp.ConnectSSL("ftps.example.com")

	ftp.Login("user", "password")

	ftp.ChangeFolder("uploads")
	ftp.Upload("report.txt", "c:\report.txt")


	ftp.Close()
End Using

For explicit SSL/TLS, code is almost the same. You first connect to non-secure port (21) and secure the connection using Ftp.AuthTLS command:

// C#

using (Ftp ftp = new Ftp())
{
    ftp.SSLConfiguration.EnabledSslProtocols = SslProtocols.Tls12;

    ftp.Connect("ftp.example.com");
    ftp.AuthTLS();

    ftp.Login("user","password");

    ftp.ChangeFolder("uploads");
    ftp.Upload("report.txt", @"c:\report.txt");

    ftp.Close();
}

' VB.NET

Using ftp As New Ftp()
	ftp.SSLConfiguration.EnabledSslProtocols = SslProtocols.Tls12

	ftp.Connect("ftp.example.com")
	ftp.AuthTLS()

	ftp.Login("user", "password")

	ftp.ChangeFolder("uploads")
	ftp.Upload("report.txt", "c:\report.txt")

	ftp.Close()
End Using

To use TLS 1.2 .NET Framework 4.5+ must be installed on your machine and you application should target .NET 4.5+.

It is possible to use TLS 1.2 in applications targeting .NET lower than 4.5, but 4.5 must be installed on the machine. After you have .NET 4.5 installed, your 2.0-4.0 apps will use the 4.5 System.dll and you can enable TLS 1.2 using this code:

    ftp.SSLConfiguration.EnabledSslProtocols = (System.Security.Authentication.SslProtocols)3072;