(Visual FoxPro) SSH Tunnel with Dynamic Port Forwarding

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.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

LOCAL loChilkatGlob
LOCAL lnSuccess
LOCAL loTunnel
LOCAL lcSshHostname
LOCAL lnSshPort
LOCAL lcUrl
LOCAL loHttp
LOCAL lcHtml
LOCAL lnWaitForThreadExit

* 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.
* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.Global')
loChilkatGlob = CreateObject('Chilkat.Global')
lnSuccess = loChilkatGlob.UnlockBundle("Anything for 30-day trial.")
IF (lnSuccess <> 1) THEN
    ? loChilkatGlob.LastErrorText
    RELEASE loChilkatGlob
    CANCEL
ENDIF

* This example requires Chilkat version 9.5.0.50 or greater.
* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.SshTunnel')
loTunnel = CreateObject('Chilkat.SshTunnel')

lcSshHostname = "sftp.example.com"
lnSshPort = 22

* Connect to an SSH server and establish the SSH tunnel:
lnSuccess = loTunnel.Connect(lcSshHostname,lnSshPort)
IF (lnSuccess <> 1) THEN
    ? loTunnel.LastErrorText
    RELEASE loChilkatGlob
    RELEASE loTunnel
    CANCEL
ENDIF

* Authenticate with the SSH server via a login/password
* or with a public key.  
* This example demonstrates SSH password authentication.
lnSuccess = loTunnel.AuthenticatePw("mySshLogin","mySshPassword")
IF (lnSuccess <> 1) THEN
    ? loTunnel.LastErrorText
    RELEASE loChilkatGlob
    RELEASE loTunnel
    CANCEL
ENDIF

* Indicate that the background SSH tunnel thread will behave as a SOCKS proxy server
* with dynamic port forwarding:
loTunnel.DynamicPortForwarding = 1

* 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.

loTunnel.InboundSocksUsername = "chilkat123"
loTunnel.InboundSocksPassword = "password123"

* Start the listen/accept thread to begin accepting SOCKS proxy client connections.
* Listen on port 1080.
lnSuccess = loTunnel.BeginAccepting(1080)
IF (lnSuccess <> 1) THEN
    ? loTunnel.LastErrorText
    RELEASE loChilkatGlob
    RELEASE loTunnel
    CANCEL
ENDIF

* 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:
lcUrl = "https://www.ethereum.org/"

* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.Http')
loHttp = CreateObject('Chilkat.Http')

* Indicate that the HTTP object is to use our portable SOCKS proxy/SSH tunnel running in our background thread.
loHttp.SocksHostname = "localhost"
loHttp.SocksPort = 1080
loHttp.SocksVersion = 5
loHttp.SocksUsername = "chilkat123"
loHttp.SocksPassword = "password123"

loHttp.SendCookies = 1
loHttp.SaveCookies = 1
loHttp.CookieDir = "memory"

* Do the HTTPS page fetch (through the SSH tunnel)
lcHtml = loHttp.QuickGetStr(lcUrl)
IF (loHttp.LastMethodSuccess <> 1) THEN
    ? loHttp.LastErrorText
    RELEASE loChilkatGlob
    RELEASE loTunnel
    RELEASE loHttp
    CANCEL
ENDIF

* Stop the background listen/accept thread:
lnWaitForThreadExit = 1
lnSuccess = loTunnel.StopAccepting(lnWaitForThreadExit)
IF (lnSuccess <> 1) THEN
    ? loTunnel.LastErrorText
    RELEASE loChilkatGlob
    RELEASE loTunnel
    RELEASE loHttp
    CANCEL
ENDIF

* Close the SSH tunnel (would also kick any remaining connected clients).
lnSuccess = loTunnel.CloseTunnel(lnWaitForThreadExit)
IF (lnSuccess <> 1) THEN
    ? loTunnel.LastErrorText
    RELEASE loChilkatGlob
    RELEASE loTunnel
    RELEASE loHttp
    CANCEL
ENDIF

RELEASE loChilkatGlob
RELEASE loTunnel
RELEASE loHttp