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Java

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

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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.

Chilkat Java Downloads

Java
import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    boolean success = false;

    // 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
    // 

    CkFtp2 ftp = new CkFtp2();

    ftp.put_Hostname("ftp.example.com");
    ftp.put_Port(21);
    ftp.put_Username("testLogin");
    ftp.put_Password("testPassword");

    // This example will use explict TLS/SSL.
    // Establish an explicit secure channel after connection
    // on the standard FTP port 21.
    ftp.put_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.put_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.)
    CkCertStore certStore = new CkCertStore();
    // 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).
    success = certStore.LoadPfxFile("test.p12","secret");
    if (success != true) {
        System.out.println(certStore.lastErrorText());
        return;
        }

    CkJsonObject jsonCN = new CkJsonObject();
    jsonCN.UpdateString("CN","cert common name");

    CkCert cert = new CkCert();
    success = certStore.FindCert(jsonCN,cert);
    if (success == false) {
        System.out.println(certStore.lastErrorText());
        return;
        }

    success = ftp.SetSslClientCert(cert);

    // Connect and login to the FTP server.
    success = ftp.Connect();
    if (success != true) {
        System.out.println(ftp.lastErrorText());
        return;
        }
    else {
        // LastErrorText contains information even when
        // successful. This allows you to visually verify
        // that the secure connection actually occurred.
        System.out.println(ftp.lastErrorText());
        }

    System.out.println("Secure FTP Channel Established!");
    System.out.println(ftp.lastErrorText());

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

    // ...
    // ...

    success = ftp.Disconnect();
  }
}