C

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. C

#include <C_CkSshTunnel.h>
#include <C_CkHttp.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkSshTunnel tunnel;
    const char *sshHostname;
    int sshPort;
    const char *url;
    HCkHttp http;
    const char *html;
    BOOL waitForThreadExit;

    success = FALSE;

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

    success = FALSE;

    tunnel = CkSshTunnel_Create();

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

    // Connect to an SSH server and establish the SSH tunnel:
    success = CkSshTunnel_Connect(tunnel,sshHostname,sshPort);
    if (success != TRUE) {
        printf("%s\n",CkSshTunnel_lastErrorText(tunnel));
        CkSshTunnel_Dispose(tunnel);
        return;
    }

    // Authenticate with the SSH server via a login/password
    // or with a public key.  
    // This example demonstrates SSH password authentication.
    success = CkSshTunnel_AuthenticatePw(tunnel,"mySshLogin","mySshPassword");
    if (success != TRUE) {
        printf("%s\n",CkSshTunnel_lastErrorText(tunnel));
        CkSshTunnel_Dispose(tunnel);
        return;
    }

    // Indicate that the background SSH tunnel thread will behave as a SOCKS proxy server
    // with dynamic port forwarding:
    CkSshTunnel_putDynamicPortForwarding(tunnel,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.

    CkSshTunnel_putInboundSocksUsername(tunnel,"chilkat123");
    CkSshTunnel_putInboundSocksPassword(tunnel,"password123");

    // Start the listen/accept thread to begin accepting SOCKS proxy client connections.
    // Listen on port 1080.
    success = CkSshTunnel_BeginAccepting(tunnel,1080);
    if (success != TRUE) {
        printf("%s\n",CkSshTunnel_lastErrorText(tunnel));
        CkSshTunnel_Dispose(tunnel);
        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:
    url = "https://www.ethereum.org/";

    http = CkHttp_Create();

    // Indicate that the HTTP object is to use our portable SOCKS proxy/SSH tunnel running in our background thread.
    CkHttp_putSocksHostname(http,"localhost");
    CkHttp_putSocksPort(http,1080);
    CkHttp_putSocksVersion(http,5);
    CkHttp_putSocksUsername(http,"chilkat123");
    CkHttp_putSocksPassword(http,"password123");

    CkHttp_putSendCookies(http,TRUE);
    CkHttp_putSaveCookies(http,TRUE);
    CkHttp_putCookieDir(http,"memory");

    // Do the HTTPS page fetch (through the SSH tunnel)
    html = CkHttp_quickGetStr(http,url);
    if (CkHttp_getLastMethodSuccess(http) != TRUE) {
        printf("%s\n",CkHttp_lastErrorText(http));
        CkSshTunnel_Dispose(tunnel);
        CkHttp_Dispose(http);
        return;
    }

    // Stop the background listen/accept thread:
    waitForThreadExit = TRUE;
    success = CkSshTunnel_StopAccepting(tunnel,waitForThreadExit);
    if (success != TRUE) {
        printf("%s\n",CkSshTunnel_lastErrorText(tunnel));
        CkSshTunnel_Dispose(tunnel);
        CkHttp_Dispose(http);
        return;
    }

    // Close the SSH tunnel (would also kick any remaining connected clients).
    success = CkSshTunnel_CloseTunnel(tunnel,waitForThreadExit);
    if (success != TRUE) {
        printf("%s\n",CkSshTunnel_lastErrorText(tunnel));
        CkSshTunnel_Dispose(tunnel);
        CkHttp_Dispose(http);
        return;
    }



    CkSshTunnel_Dispose(tunnel);
    CkHttp_Dispose(http);

    }