DataFlex

Start an SSH Tunnel Listener (BeginAccepting)

Demonstrates the Chilkat SshTunnel.BeginAccepting method, which creates and starts the local listener on the given port. The only argument is the listen port. Connect and authenticate first — clients accepted before authentication cannot be forwarded. The IsAccepting property reports whether the listener is running.

Background: This is the step that actually turns the object into a working tunnel: it spawns a background thread that accepts local TCP connections and forwards each through the authenticated SSH transport. Because the forwarding runs on its own thread, control returns to your program immediately and the tunnel operates while the rest of the application does other work — which is why a separate CloseTunnel is needed to shut it down cleanly.

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DataFlex

Use ChilkatAx-win32.pkg

Procedure Test
    Boolean iSuccess
    Handle hoTunnel
    Integer iSshPort
    String sPassword
    Integer iListenPort
    Boolean iWaitForThreadExit
    String sTemp1
    Boolean bTemp1

    Move False To iSuccess

    //  Demonstrates the SshTunnel.BeginAccepting method, which creates and starts the local listener
    //  on the given port.  The only argument is the listen port.  Connect and authenticate first;
    //  clients accepted before authentication cannot be forwarded.

    Get Create (RefClass(cComChilkatSshTunnel)) To hoTunnel
    If (Not(IsComObjectCreated(hoTunnel))) Begin
        Send CreateComObject of hoTunnel
    End

    Set ComDestHostname Of hoTunnel To "db.internal.example.com"
    Set ComDestPort Of hoTunnel To 5432

    Move 22 To iSshPort
    Get ComConnect Of hoTunnel "ssh.example.com" iSshPort To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoTunnel To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    //  Normally you would not hard-code the password in source.  You should instead obtain it
    //  from an interactive prompt, environment variable, or a secrets vault.
    Move "mySshPassword" To sPassword

    Get ComAuthenticatePw Of hoTunnel "mySshLogin" sPassword To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoTunnel To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    //  Start the local listener.  Local TCP connections to this port are forwarded to DestHostname:DestPort
    //  through the SSH server.
    Move 1080 To iListenPort
    Get ComBeginAccepting Of hoTunnel iListenPort To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoTunnel To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    //  IsAccepting reports whether the listener thread is running.
    Get ComIsAccepting Of hoTunnel To bTemp1
    If (bTemp1) Begin
        Showln "The tunnel is accepting connections on port " iListenPort
    End

    //  ... the tunnel forwards traffic on a background thread while your application runs ...

    Move True To iWaitForThreadExit
    Get ComCloseTunnel Of hoTunnel iWaitForThreadExit To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoTunnel To sTemp1
        Showln sTemp1
        Procedure_Return
    End



End_Procedure