Java

SSH Tunnel with Dynamic Port Forwarding

See more SSH Examples

Demonstrates how to start a background thread that runs a portable SSH tunnel w/ dynamic port forwarding that the foreground thread can use for establishing connections through an SSH tunnel. Chilkat2 Java

import com.chilkatsoft.chilkat2.ChilkatException;
import com.chilkatsoft.chilkat2.Http;
import com.chilkatsoft.chilkat2.SshTunnel;

public class ChilkatExample {

    public static void main(String[] args) {
        boolean success = false;

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

        success = false;

        SshTunnel tunnel = new SshTunnel();

        String sshHostname = "sftp.example.com";
        int sshPort = 22;

        // Connect to an SSH server and establish the SSH tunnel:
        try {
            tunnel.connect(sshHostname, sshPort);

            // Authenticate with the SSH server via a login/password
            // or with a public key.
            // This example demonstrates SSH password authentication.
            tunnel.authenticatePw("mySshLogin", "mySshPassword");

            // Indicate that the background SSH tunnel thread will behave as a SOCKS proxy server
            // with dynamic port forwarding:
            tunnel.setDynamicPortForwarding(true);

            // We may optionally require that connecting clients authenticate with our SOCKS proxy server.
            // To do this, set an inbound username/password.  Any connecting clients would be required to
            // use SOCKS5 with the correct username/password.
            // If no inbound username/password is set, then our SOCKS proxy server will accept both
            // SOCKS4 and SOCKS5 unauthenticated connections.

            tunnel.setInboundSocksUsername("chilkat123");
            tunnel.setInboundSocksPassword("password123");

            // Start the listen/accept thread to begin accepting SOCKS proxy client connections.
            // Listen on port 1080.
            tunnel.beginAccepting(1080);
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        // Now that a background thread is running a SOCKS proxy server that forwards connections
        // through an SSH tunnel, it is possible to use any Chilkat implemented protocol that is SOCKS capable,
        // such as HTTP, POP3, SMTP, IMAP, FTP, etc.  The protocol may use SSL/TLS because the SSL/TLS
        // will be passed through the SSH tunnel to the end-destination.  Also, any number of simultaneous
        // connections may be routed through the SSH tunnel.

        // For this example, let's do a simple HTTPS request:
        String url = "https://www.ethereum.org/";

        Http http = new Http();

        // Indicate that the HTTP object is to use our portable SOCKS proxy/SSH tunnel running in our background thread.
        http.setSocksHostname("localhost");
        http.setSocksPort(1080);
        http.setSocksVersion(5);
        http.setSocksUsername("chilkat123");
        http.setSocksPassword("password123");

        http.setSendCookies(true);
        http.setSaveCookies(true);
        http.setCookieDir("memory");

        // Do the HTTPS page fetch (through the SSH tunnel)
        String html;
        try {
            html = http.quickGetStr(url);
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        // Stop the background listen/accept thread:
        boolean waitForThreadExit = true;
        try {
            tunnel.stopAccepting(waitForThreadExit);

            // Close the SSH tunnel (would also kick any remaining connected clients).
            tunnel.closeTunnel(waitForThreadExit);
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }
    }
}