(.NET Core C#) Secure FTP with Client Certificate

Chilkat FTP2 provides the ability to use a client certificate with secure FTP (implicit or explicit SSL/TLS). This example demonstrates how to load a certificate from a .pfx and use it as the client-side SSL cert. Note: Client-side certificates are only needed in situations where the server demands one.

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

Chilkat.Ftp2 ftp = new Chilkat.Ftp2();

ftp.Hostname = "ftp.***.com";
ftp.Port = 21;
ftp.Username = "test";
ftp.Password = "test";

// This example will use explict TLS/SSL.
// Establish an explicit secure channel after connection
// on the standard FTP port 21.
ftp.AuthTls = true;

// The Ssl property is for establishing an implicit SSL connection
// on port 990.  Because this example uses explicit SSL, it 
// should remain false.
ftp.Ssl = false;

// Load a certificate from a .pfx
// A PFX may contain several certs, including the certificates
// in a chain of authority.
Chilkat.CertStore certStore = new Chilkat.CertStore();
string password;
password = "***";
// Load the certs from a PFX into an in-memory certificate store:
bool success = certStore.LoadPfxFile("chilkat.pfx",password);
if (success != true) {
    Debug.WriteLine(certStore.LastErrorText);
    return;
}

// Find the exact cert we'll use:
Chilkat.Cert cert = null;
cert = certStore.FindCertBySubject("Chilkat Software, Inc.");
if (certStore.LastMethodSuccess == false) {
    Debug.WriteLine("Certificate not found!");
    return;
}

// Use this certificate for our secure (SSL/TLS) connection:
success = ftp.SetSslClientCert(cert);

// Connect and login to the FTP server.  The connection is 
// made secure because of the AuthTls setting.
success = ftp.Connect();
if (success != true) {
    Debug.WriteLine(ftp.LastErrorText);
    return;
}
else {
    // LastErrorText contains information even when
    // successful. This allows you to visually verify
    // that the secure connection actually occurred.
    Debug.WriteLine(ftp.LastErrorText);
}

Debug.WriteLine("Secure FTP Channel Established!");

// Do whatever you're doing to do ...
// upload files, download files, etc...

// .....
// .....

success = ftp.Disconnect();