(Java) SSH Public Key Authentication

Demonstrates how to authenticate with an SSH server using public key authentication.

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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[])
  {
    // This example assumes the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    CkSsh ssh = new CkSsh();

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

    // Connect to the SSH server.  
    // The standard SSH port = 22
    // The hostname may be a hostname or IP address.
    String hostname = "sftp.example.com";
    int port = 22;
    boolean success = ssh.Connect(hostname,port);
    if (success != true) {
        System.out.println(ssh.lastErrorText());
        return;
        }

    CkSshKey key = new CkSshKey();

    // Read the PEM file into a string variable:
    // (This does not load the PEM file into the key.  The LoadText
    // method is a convenience method for loading the full contents of ANY text
    // file into a string variable.)
    String privKey = key.loadText("myPrivateKey.pem");
    if (key.get_LastMethodSuccess() != true) {
        System.out.println(key.lastErrorText());
        return;
        }

    // Load a private key from a PEM string:
    // (Private keys may be loaded from OpenSSH and Putty formats.
    // Both encrypted and unencrypted private key file formats
    // are supported.  This example loads an unencrypted private
    // key in OpenSSH format.  PuTTY keys typically use the .ppk
    // file extension, while OpenSSH keys use the PEM format.
    // (For PuTTY keys, call FromPuttyPrivateKey instead.)
    success = key.FromOpenSshPrivateKey(privKey);
    if (success != true) {
        System.out.println(key.lastErrorText());
        return;
        }

    // Authenticate with the SSH server using the login and
    // private key.  (The corresponding public key should've 
    // been installed on the SSH server beforehand.)
    success = ssh.AuthenticatePk("myLogin",key);
    if (success != true) {
        System.out.println(ssh.lastErrorText());
        return;
        }

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