Secure FTP with .crt and .pvk (private key file)

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 separate .crt (or .cer) and .pvk files and use it as the client-side SSL cert. The .pvk contains the private key. The .crt/.cer file contains the PEM or DER encoded digital certificate. Note: Client-side certificates are only needed in situations where the server demands one.

Download Chilkat Java Library

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[])
  {
    CkFtp2 ftp = new CkFtp2();

    boolean success;

    //  Any string unlocks the component for the 1st 30-days.
    success = ftp.UnlockComponent("Anything for 30-day trial");
    if (success != true) {
        System.out.println(ftp.lastErrorText());
        return;
    }

    //  You may use this account for testing.
    //  This account allows for directory listings and files
    //  to be downloaded.  However, file uploads are not allowed.
    ftp.put_Hostname("ftp.secureftp-test.com");
    ftp.put_Username("test");
    ftp.put_Password("test");

    //  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.  Do not set it.
    ftp.put_Ssl(false);

    CkCert cert = new CkCert();

    //  LoadFromFile will load either PEM and DER formatted files.
    //  It automatically recognizes the file format based on the
    //  file contents.
    success = cert.LoadFromFile("Test.crt");
    if (success != true) {
        System.out.println(cert.lastErrorText());
        return;
    }

    String password;
    password = "test";
    CkPrivateKey pvk = new CkPrivateKey();
    success = pvk.LoadPvkFile("Test.pvk",password);
    if (success != true) {
        System.out.println(pvk.lastErrorText());
        return;
    }

    //  Import the private key to a Windows key container and link
    //  it to the certificate.  (It's OK if the key is already
    //  imported and present in the key container...)
    boolean bForSigning;
    boolean bForKeyExchange;
    boolean bMachineKeyset;
    boolean bNeedPrivateKeyAccess;
    String keyContainerName;

    //  Choose anything for the key container name.
    keyContainerName = "MyCertForFtp";

    //  We'll import the key to our logged-on user keyset rather
    //  than the machine keyset:
    bMachineKeyset = false;

    bNeedPrivateKeyAccess = true;

    //  Create a key container and import the private key.
    CkKeyContainer keyContainer = new CkKeyContainer();
    success = keyContainer.OpenContainer(keyContainerName,bNeedPrivateKeyAccess,bMachineKeyset);
    if (success != true) {
        success = keyContainer.CreateContainer(keyContainerName,bMachineKeyset);
    }

    if (success != true) {
        System.out.println(keyContainer.lastErrorText());
        return;
    }

    //  Import the private key into the key container.
    //  We're using the key for key exchange, not signing:
    bForKeyExchange = false;
    success = keyContainer.ImportPrivateKey(pvk,bForKeyExchange);
    if (success != true) {
        System.out.println(keyContainer.lastErrorText());
        return;
    }

    //  Link the cert with the private key in the key container.
    bForSigning = true;
    success = cert.LinkPrivateKey(keyContainerName,bMachineKeyset,bForSigning);
    if (success != true) {
        System.out.println(cert.lastErrorText());
        return;
    }

    //  The cert now has access to a private key and is ready to be
    //  used...

    //  Use this certificate for our secure (SSL/TLS) connection:
    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) {
        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!");

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

    ftp.Disconnect();

    //  The LastErrorText provides a detailed log of the
    //  SSL connection for both success and failed connections.
    //  Here is an example of a successful connection.
    //  The client certificate is logged as "ClientCertDN":

    //  ChilkatLog:
    //    Connect:
    //      DllDate: Aug 15 2007
    //      Hostname: ftp.secureftp-test.com
    //      Port: 21
    //      IdleTimeoutMs: 60000
    //      ConnectTimeout: 60
    //      HeartbeatMs: 0
    //      initialStatus: 220
    //      initialResponse: 220 FileZilla Server version 0.9.23 beta
    //      converting to secure connection...
    //      ClientCertDN: C=US, S=Illinois, L=Wheaton, O="Chilkat Software, Inc.", OU=Secure Application Development, CN="Chilkat Software, Inc."
    //      SSL Server Certificate not verified.
    //      ConnectionInfo:
    //        protocol: TLS1
    //        cipher: RC4
    //        cipherStrength: 128
    //        hash: MD5
    //        hashStrength: 128
    //        keyExchange: RSA
    //        keyExchangeStrength: 1024
    //      Secure Channel Established.
    //      successfully converted to secure connection...
    //      Features: 211-Features:
    //   MDTM
    //   REST STREAM
    //   SIZE
    //   MLST type*;size*;modify*;
    //   MLSD
    //   AUTH SSL
    //   AUTH TLS
    //   UTF8
    //   CLNT
    //   MFMT
    //  211 End
    //      Directory listings are utf-8
    //      Logging in...
    //      Username: test
    //      Login successful.
    //      Connect successful

  }
}