(C#) Using WS_FTP Self-signed Certificate file (.crt) and Private Key File. (.key)

Demonstrates how to use a self-signed certificate created by WS_FTP with Chilkat FTP2.

Note: It is usually not necessary for the FTP client to use a client-side certificate. Most FTP servers using SSL and TLS connections (explicit or implicit) do not require client-side certs. In addition, some high-security FTP servers require "real" certificates -- meaning certificates issued by a real certificate authority with a chain of authentication that leads to a trusted root certificate. The certificates created by WS_FTP are self-signed and untrusted.

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

// Important:  Before running this program, convert your
// .crt and .key files to a .p12 using OpenSSL:
// The command is this:
// openssl pkcs12 -export -in test.crt -inkey test.key -out test.p12
// 

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

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

// 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;

// Create an instance of a certificate store object, load a .p12 file,
// locate the certificate we need, and use it for signing.
// (a P12/PFX file may contain more than one certificate.)
Chilkat.CertStore certStore = new Chilkat.CertStore();
// The 1st argument is the filename, the 2nd arg is the 
// .p12 file's password.  (OpenSSL will prompty you to set a password
// when converting the .crt and .key into a .p12).
bool success = certStore.LoadPfxFile("test.p12","secret");
if (success != true) {
    Debug.WriteLine(certStore.LastErrorText);
    return;
}

Chilkat.Cert cert = certStore.FindCertBySubjectCN("Your cert's common name");
if (certStore.LastMethodSuccess == false) {
    Debug.WriteLine(certStore.LastErrorText);
    return;
}

success = ftp.SetSslClientCert(cert);

// Connect and login to the FTP server.
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!");
Debug.WriteLine(ftp.LastErrorText);

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

// ...
// ...

success = ftp.Disconnect();