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Java

SFTP Public-Key Authentication (id_ed25519)

See more SFTP Examples

Demonstrates how to authenticate with an SSH/SFTP server using publickey authentication with an Ed25519 private key (id_ed25519).

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

    CkSshKey key = new CkSshKey();

    // The id_ed25519 file should contain something like this:
    // (You can open it in a text editor..)

    // -----BEGIN OPENSSH PRIVATE KEY-----
    // b3BlbnNzaC1rZXktdjEAAAAACmFlczI1Ni1jdHIAAAAGYmNyeXB0AAAAGAAAABDIeK9+Xw
    // 6Do9gnhtrJu5iJAAAAZAAAAAEAAAAzAAAAC3NzaC1lZDI1NTE5AAAAIMh/Ge7fjQCssmVd
    // BqjYZbRAI0pY8IrnB6J1yLetq34OAAAAoMVP7cvy4hTiAINA3I4v55OonkpKza8mzfUW18
    // RDQeYL3ovCVaAYOGcCpf/SW3QiY6tnXq+5WDEfJ7Z/kQ0nl2+1wSLOytxpyO+IY0rRtLrX
    // 6e/agR4nbZpt/MFG6xqcNASbtDgg+9IWGvDrtXOLFofx07/zml+UjFL0tXRpCjOxeqKyXH
    // t8SRgdT97d9/bYPwapaXY+b2DVVy5/LVx4Sq8=
    // -----END OPENSSH PRIVATE KEY-----

    String privKeyText = key.loadText("c:/temp/id_ed25519");
    if (key.get_LastMethodSuccess() != true) {
        System.out.println(key.lastErrorText());
        return;
        }

    // If your private key was saved encrypted, then you'll need the password.
    // In this example, the password "blahblah" is valid for the above key -- which is a real Ed25519 key generated/saved from puttygen.
    key.put_Password("blahblah");

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

    CkSFtp sftp = new CkSFtp();

    // Set some timeouts, in milliseconds:
    sftp.put_ConnectTimeoutMs(5000);
    sftp.put_IdleTimeoutMs(15000);

    String hostname = "sftp.example.com";
    int port = 22;
    success = sftp.Connect(hostname,port);
    if (success != true) {
        System.out.println(sftp.lastErrorText());
        return;
        }

    // Authenticate with the SSH server.  Chilkat SFTP supports
    // both password-based authenication as well as public-key
    // authentication.  
    success = sftp.AuthenticatePk("myLogin",key);
    if (success != true) {
        System.out.println(sftp.lastErrorText());
        return;
        }

    System.out.println(sftp.lastErrorText());
    System.out.println("Public-Key Authentication Successful!");

    // Now go do whatever you're app needs to do...
  }
}