(Lianja) SSH Tunnel (Port Forwarding via direct-tcpip channel)

Demonstrates how to create an SSH tunnel to a remote hostname:port via a direct-tcpip channel.

Chilkat Lianja Extension Download Chilkat Lianja Extension

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

loSsh = createobject("CkSsh")

// Connect to an SSH server:

// Hostname may be an IP address or hostname:
lcHostname = "192.168.1.117"
lnPort = 22

llSuccess = loSsh.Connect(lcHostname,lnPort)
if (llSuccess <> .T.) then
    ? loSsh.LastErrorText
    release loSsh
    return
endif

// Wait a max of 5 seconds when reading responses..
loSsh.IdleTimeoutMs = 5000

// Authenticate using login/password:
llSuccess = loSsh.AuthenticatePw("chilkat","myPassword")
if (llSuccess <> .T.) then
    ? loSsh.LastErrorText
    release loSsh
    return
endif

// Open a direct-tcpip channel.  We want the SSH server to connect
// to www.chilkatsoft.com, port 80 (i.e. the web server).
// Data sent through the SSH tunnel is forwarded to the remote
// host:port.  (Note: The remote host:port does not need to be 
// a web server.  It can be anything.  It can be your own
// customer application server that listens on a port, or any
// other type of server.)
// When we read from the SSH channel, we'll be reading data
// sent from the remote host:port (i.e. the web server in this
// example).

lnChannelNum = loSsh.OpenDirectTcpIpChannel("www.chilkatsoft.com",80)
if (lnChannelNum < 0) then
    ? loSsh.LastErrorText
    release loSsh
    return
endif

// Build a simple HTTP GET request for http://www.chilkatsoft.com/xyz.html
lcHttpReq = "GET /xyz123.html HTTP/1.1" + Chr(13) + Chr(10) + "Host: www.chilkatsoft.com" + Chr(13) + Chr(10) + Chr(13) + Chr(10)

// Send the HTTP request:
llSuccess = loSsh.ChannelSendString(lnChannelNum,lcHttpReq,"ansi")
if (llSuccess <> .T.) then
    ? loSsh.LastErrorText
    release loSsh
    return
endif

// Get the HTTP response.
// First read the HTTP response header which ends with a double CRLF.
// Calling ChannelReceiveUntilMatch will receive until match string is seen,
// or until a timeout occurs (IdleTimeoutMs property).  ChannelReceiveUntilMatch
// may read beyond the match string, but it will stop reading as soon as the match
// string is seen.
llCaseSensitive = .F.
lcMatchStr = Chr(13) + Chr(10) + Chr(13) + Chr(10)
llSuccess = loSsh.ChannelReceiveUntilMatch(lnChannelNum,lcMatchStr,"ansi",llCaseSensitive)
if (llSuccess <> .T.) then
    ? loSsh.LastErrorText
    release loSsh
    return
endif

// Extract the HTTP header from the receive buffer.
// (GetReceiveTextS extracts up to and including the match string from the receive buffer)

lcResponseHeader = loSsh.GetReceivedTextS(lnChannelNum,lcMatchStr,"ansi")
? "---- HTTP Response Header ----"
? lcResponseHeader

// Now get the body of the HTTP response (this is the HTML content
// of http://www.chilkatsoft.com/xyz.html
// It's possible we've already received the entire HTTP response in the
// call to ChannelReceiveUntilMatch.  Therefore, we'll poll for any remaining data
// and wait a max of .2 seconds.

lnPollTimeoutMs = 200
lnNumBytesRead = loSsh.ChannelPoll(lnChannelNum,lnPollTimeoutMs)
// We're not checking for an error here.
// A return value of -2 means that no data was available and the poll simply timed out (not an error)
// A return value of -1 indicates an error.
// A return value greater than 0 indicates that additional data was received.

? "---- HTML BODY ----"

// Extract the remainder of the accumulated data in the internal receive buffer.
// This should be our HTML body:

lcHtmlBody = loSsh.GetReceivedText(lnChannelNum,"ansi")
? lcHtmlBody

// Close the channel:
llSuccess = loSsh.ChannelSendClose(lnChannelNum)
if (llSuccess <> .T.) then
    ? loSsh.LastErrorText
    release loSsh
    return
endif

// Disconnect
loSsh.Disconnect()


release loSsh