Java

Get the SSH Server's Authentication Methods

Demonstrates the Chilkat Ssh.GetAuthMethods method, which queries a connected but unauthenticated SSH server for the authentication methods it advertises. It takes no arguments and returns a lowercase, comma-separated list such as publickey,password,keyboard-interactive. Call it after Connect and before authenticating.

Background: Knowing what the server accepts lets a client choose the right authentication path — for example, falling back to keyboard-interactive when password auth is not offered. Note the documented connection side effect: querying methods advances the SSH authentication state, so call it at the correct point in the sequence.

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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 Ssh.GetAuthMethods method, which queries a connected but unauthenticated SSH
    //  server for the authentication methods it advertises.  It takes no arguments and returns a
    //  lowercase, comma-separated list such as "publickey,password,keyboard-interactive".

    CkSsh ssh = new CkSsh();

    //  Connect to the SSH server.  Port 22 is the usual SSH port.
    int sshPort = 22;
    success = ssh.Connect("ssh.example.com",sshPort);
    if (success == false) {
        System.out.println(ssh.lastErrorText());
        return;
        }

    //  Query the advertised authentication methods.  Call after Connect, before authenticating.
    String methods = ssh.getAuthMethods();
    if (ssh.get_LastMethodSuccess() == false) {
        System.out.println(ssh.lastErrorText());
        return;
        }

    System.out.println("Server auth methods: " + methods);

    ssh.Disconnect();
  }
}