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Java

SFTP Authenticate with Password and Private Key

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Demonstrates the Chilkat SFtp.AuthenticatePwPk method, which authenticates with a server that requires both a password and a private key. The arguments are the username, the password, and an SshKey private key.

Note: The private-key path is relative to the application's current working directory. Supply the path to your own key file.

Background: Most servers require either a password or a public key, not both — but some high-security deployments mandate two-factor SSH, combining something you know (the password) with something you have (the key). This method satisfies that policy in one call. As always, the password should come from a secure source rather than a literal in code.

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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;

    //  Demonstrates the SFtp.AuthenticatePwPk method, which authenticates with a server that requires
    //  BOTH a password and a private key.  The 1st argument is the username, the 2nd is the password,
    //  and the 3rd is an SshKey private key.

    CkSFtp sftp = new CkSFtp();

    //  Step 1: Connect the SSH transport.  Port 22 is the usual port.
    int port = 22;
    success = sftp.Connect("sftp.example.com",port);
    if (success == false) {
        System.out.println(sftp.lastErrorText());
        return;
        }

    //  Normally you would not hard-code the password in source.  You should instead obtain it
    //  from an interactive prompt, environment variable, or a secrets vault.
    String password = "mySshPassword";

    //  Load the SSH private key.  LoadText reads the file's text, which is then imported.
    CkSshKey privKey = new CkSshKey();
    String keyText = privKey.loadText("qa_data/id_rsa");
    if (privKey.get_LastMethodSuccess() == false) {
        System.out.println(privKey.lastErrorText());
        return;
        }

    success = privKey.FromOpenSshPrivateKey(keyText);
    if (success == false) {
        System.out.println(privKey.lastErrorText());
        return;
        }

    success = sftp.AuthenticatePwPk("mySshLogin",password,privKey);
    if (success == false) {
        System.out.println(sftp.lastErrorText());
        return;
        }

    //  Step 3: Open the SFTP subsystem.  This must be done after authentication and before any
    //  file or directory operations.
    success = sftp.InitializeSftp();
    if (success == false) {
        System.out.println(sftp.lastErrorText());
        return;
        }

    System.out.println("Authenticated with a password and a private key.");

    sftp.Disconnect();
  }
}