(C++) FTP through SSH Tunnel

Demonstrates how to FTP through an SSH tunnel.

The Chilkat SSH tunnel object is used to create a portable SSH tunnel w/ dynamic port forwarding on a background thread that the foreground thread can use for establishing connections through an SSH tunnel.

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#include <CkGlobal.h>
#include <CkSshTunnel.h>
#include <CkFtp2.h>

void ChilkatSample(void)
    {
    // Starting in v9.5.0.49, all Chilkat classes can be unlocked at once at the beginning of a program
    // by calling UnlockBundle.  It requires a Bundle unlock code.
    CkGlobal chilkatGlob;
    bool success = chilkatGlob.UnlockBundle("Anything for 30-day trial.");
    if (success != true) {
        std::cout << chilkatGlob.lastErrorText() << "\r\n";
        return;
    }

    // This example requires Chilkat version 9.5.0.50 or greater.
    CkSshTunnel tunnel;

    const char *sshHostname = "www.my-ssh-server.com";
    int sshPort = 22;

    // Connect to an SSH server and establish the SSH tunnel:
    success = tunnel.Connect(sshHostname,sshPort);
    if (success != true) {
        std::cout << tunnel.lastErrorText() << "\r\n";
        return;
    }

    // Authenticate with the SSH server via a login/password
    // or with a public key.  
    // This example demonstrates SSH password authentication.
    success = tunnel.AuthenticatePw("mySshLogin","mySshPassword");
    if (success != true) {
        std::cout << tunnel.lastErrorText() << "\r\n";
        return;
    }

    // Indicate that the background SSH tunnel thread will behave as a SOCKS proxy server
    // with dynamic port forwarding:
    tunnel.put_DynamicPortForwarding(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.put_InboundSocksUsername("chilkat123");
    tunnel.put_InboundSocksPassword("password123");

    // Start the listen/accept thread to begin accepting SOCKS proxy client connections.
    // Listen on port 1080.
    success = tunnel.BeginAccepting(1080);
    if (success != true) {
        std::cout << tunnel.lastErrorText() << "\r\n";
        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 Socket, 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.

    // Let's do an FTP upload through the SSH tunnel.  Both the control and data connections 
    // go through the tunnel.
    CkFtp2 ftp;

    ftp.put_Hostname("ftp.example.com");
    ftp.put_Username("login");
    ftp.put_Password("password");

    // Indicate that the FTP2 object is to use our portable SOCKS proxy/SSH tunnel running in our background thread.
    ftp.put_SocksHostname("localhost");
    ftp.put_SocksPort(1080);
    ftp.put_SocksVersion(5);
    ftp.put_SocksUsername("chilkat123");
    ftp.put_SocksPassword("password123");

    // Connect to the FTP server
    success = ftp.ConnectOnly();
    if (success != true) {
        std::cout << ftp.lastErrorText() << "\r\n";
        return;
    }

    // Authenticate with the FTP server.
    success = ftp.LoginAfterConnectOnly();
    if (success != true) {
        std::cout << ftp.lastErrorText() << "\r\n";
        return;
    }

    // Change to the remote directory where the file will be uploaded.
    success = ftp.ChangeRemoteDir("junk");
    if (success != true) {
        std::cout << ftp.lastErrorText() << "\r\n";
        return;
    }

    // Upload a file.
    const char *localPath = "/temp/hamlet.xml";
    const char *remoteFilename = "hamlet.xml";

    success = ftp.PutFile(localPath,remoteFilename);
    if (success != true) {
        std::cout << ftp.lastErrorText() << "\r\n";
        return;
    }

    // This closes the SSH channel within the SSH tunnel,
    // and thus closes the connection with the FTP server.
    success = ftp.Disconnect();

    std::cout << "File Uploaded!" << "\r\n";

    // Stop the background listen/accept thread:
    bool waitForThreadExit = true;
    success = tunnel.StopAccepting(waitForThreadExit);
    if (success != true) {
        std::cout << tunnel.lastErrorText() << "\r\n";
        return;
    }

    // Close the SSH tunnel (would also kick any remaining connected clients).
    success = tunnel.CloseTunnel(waitForThreadExit);
    if (success != true) {
        std::cout << tunnel.lastErrorText() << "\r\n";
        return;
    }
    }