(SQL Server) SSH Tunnel Inside another SSH Tunnel

Demonstrates how to create a TCP/IP socket connection through an SSH tunnel that is dynamic port forwarded through another SSH tunnel.

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

-- Important: See this note about string length limitations for strings returned by sp_OAMethod calls.
--
CREATE PROCEDURE ChilkatSample
AS
BEGIN
    DECLARE @hr int
    DECLARE @iTmp0 int
    -- Important: Do not use nvarchar(max).  See the warning about using nvarchar(max).
    DECLARE @sTmp0 nvarchar(4000)
    -- This example requires the Chilkat API to have been previously unlocked.
    -- See Global Unlock Sample for sample code.

    -- This example requires Chilkat version 9.5.0.50 or greater.
    DECLARE @tunnel int
    -- Use "Chilkat_9_5_0.SshTunnel" for versions of Chilkat < 10.0.0
    EXEC @hr = sp_OACreate 'Chilkat.SshTunnel', @tunnel OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    END

    DECLARE @sshHostname nvarchar(4000)
    SELECT @sshHostname = 'www.ssh-serverA.com'
    DECLARE @sshPort int
    SELECT @sshPort = 22

    -- Connect to an SSH server and establish the SSH tunnel:
    DECLARE @success int
    EXEC sp_OAMethod @tunnel, 'Connect', @success OUT, @sshHostname, @sshPort
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @tunnel, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @tunnel
        RETURN
      END

    -- Authenticate with the SSH server via a login/password
    -- or with a public key.  
    -- This example demonstrates SSH password authentication.
    EXEC sp_OAMethod @tunnel, 'AuthenticatePw', @success OUT, 'mySshLogin', 'mySshPassword'
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @tunnel, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @tunnel
        RETURN
      END

    -- Indicate that the background SSH tunnel thread will behave as a SOCKS proxy server
    -- with dynamic port forwarding:
    EXEC sp_OASetProperty @tunnel, '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.

    EXEC sp_OASetProperty @tunnel, 'InboundSocksUsername', 'chilkat123'
    EXEC sp_OASetProperty @tunnel, 'InboundSocksPassword', 'password123'

    -- Start the listen/accept thread to begin accepting SOCKS proxy client connections.
    -- Listen on port 1080.
    EXEC sp_OAMethod @tunnel, 'BeginAccepting', @success OUT, 1080
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @tunnel, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @tunnel
        RETURN
      END

    -- 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, Socket, 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.

    DECLARE @tunnelB int
    -- Use "Chilkat_9_5_0.Socket" for versions of Chilkat < 10.0.0
    EXEC @hr = sp_OACreate 'Chilkat.Socket', @tunnelB OUT

    -- Indicate that the socket object is to use our portable SOCKS proxy/SSH tunnel running in our background thread.
    EXEC sp_OASetProperty @tunnelB, 'SocksHostname', 'localhost'
    EXEC sp_OASetProperty @tunnelB, 'SocksPort', 1080
    EXEC sp_OASetProperty @tunnelB, 'SocksVersion', 5
    EXEC sp_OASetProperty @tunnelB, 'SocksUsername', 'chilkat123'
    EXEC sp_OASetProperty @tunnelB, 'SocksPassword', 'password123'

    -- Open a new SSH tunnel through the existing tunnel (via what we treat as a SOCKS5 proxy,
    -- but it is actually a dynamic port-forwarded SSH tunnel).
    EXEC sp_OAMethod @tunnelB, 'SshOpenTunnel', @success OUT, 'www.ssh-serverB.com', 22
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @tunnelB, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @tunnel
        EXEC @hr = sp_OADestroy @tunnelB
        RETURN
      END

    -- Authenticate with ssh-serverB.com
    EXEC sp_OAMethod @tunnelB, 'SshAuthenticatePw', @success OUT, 'uname', 'pwd'
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @tunnelB, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @tunnel
        EXEC @hr = sp_OADestroy @tunnelB
        RETURN
      END

    -- OK, the SSH tunnel (within a tunnel) is setup.  Now open a channel within the tunnel.
    -- Once the channel is obtained, the Socket API may
    -- be used exactly the same as usual, except all communications
    -- are sent through the channel in the SSH tunnel.
    -- Any number of channels may be created from the same SSH tunnel.
    -- Multiple channels may coexist at the same time.

    -- Connect to an NIST time server and read the current date/time
    DECLARE @channel int

    DECLARE @maxWaitMs int
    SELECT @maxWaitMs = 4000
    DECLARE @useTls int
    SELECT @useTls = 0
    EXEC sp_OAMethod @tunnelB, 'SshOpenChannel', @channel OUT, 'time-c.nist.gov', 37, @useTls, @maxWaitMs
    EXEC sp_OAGetProperty @tunnelB, 'LastMethodSuccess', @iTmp0 OUT
    IF @iTmp0 = 0
      BEGIN
        EXEC sp_OAGetProperty @tunnelB, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @tunnel
        EXEC @hr = sp_OADestroy @tunnelB
        RETURN
      END

    -- The time server will send a big-endian 32-bit integer representing
    -- the number of seconds since since 00:00 (midnight) 1 January 1900 GMT.
    -- The ReceiveInt32 method will receive a 4-byte integer, but returns
    -- 1 or 0 to indicate success.  If successful, the integer
    -- is obtained via the ReceivedInt property.
    DECLARE @bigEndian int
    SELECT @bigEndian = 1
    EXEC sp_OAMethod @channel, 'ReceiveInt32', @success OUT, @bigEndian
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @channel, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @channel

        EXEC @hr = sp_OADestroy @tunnel
        EXEC @hr = sp_OADestroy @tunnelB
        RETURN
      END

    DECLARE @dt int
    -- Use "Chilkat_9_5_0.CkDateTime" for versions of Chilkat < 10.0.0
    EXEC @hr = sp_OACreate 'Chilkat.CkDateTime', @dt OUT

    EXEC sp_OAGetProperty @channel, 'ReceivedInt', @iTmp0 OUT
    EXEC sp_OAMethod @dt, 'SetFromNtpTime', @success OUT, @iTmp0

    -- Show the current local date/time
    DECLARE @bLocalTime int
    SELECT @bLocalTime = 1

    EXEC sp_OAMethod @dt, 'GetAsRfc822', @sTmp0 OUT, @bLocalTime
    PRINT 'Current local date/time: ' + @sTmp0

    -- Close the SSH channel.
    EXEC sp_OAMethod @channel, 'Close', @success OUT, @maxWaitMs
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @channel, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @channel

        EXEC @hr = sp_OADestroy @tunnel
        EXEC @hr = sp_OADestroy @tunnelB
        EXEC @hr = sp_OADestroy @dt
        RETURN
      END

    EXEC @hr = sp_OADestroy @channel

    -- Stop the background listen/accept thread:
    DECLARE @waitForThreadExit int
    SELECT @waitForThreadExit = 1
    EXEC sp_OAMethod @tunnel, 'StopAccepting', @success OUT, @waitForThreadExit
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @tunnel, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @tunnel
        EXEC @hr = sp_OADestroy @tunnelB
        EXEC @hr = sp_OADestroy @dt
        RETURN
      END

    -- Close the SSH tunnel (would also kick any remaining connected clients).
    EXEC sp_OAMethod @tunnel, 'CloseTunnel', @success OUT, @waitForThreadExit
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @tunnel, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @tunnel
        EXEC @hr = sp_OADestroy @tunnelB
        EXEC @hr = sp_OADestroy @dt
        RETURN
      END

    EXEC @hr = sp_OADestroy @tunnel
    EXEC @hr = sp_OADestroy @tunnelB
    EXEC @hr = sp_OADestroy @dt


END
GO