Xbase++

TCP or TLS over Multiple Hop SSH to Remote Server

See more Socket/SSL/TLS Examples

Demonstrates how to use the Chilkat Socket API to connect to a remote server (using TCP or TLS) tunneled through mulitple-hop SSH. The scheme looks like this:

Application => ServerSSH1 => ServerSSH2 => DestinationServer

The ConnectThroughSsh and UseSsh methods are added in Chilkat version 9.5.0.55 to accomplish this task.

Xbase++

LOCAL nSuccess
LOCAL oSsh1
LOCAL oSsh2
LOCAL oSocket
LOCAL nUseTls
LOCAL nMaxWaitMillisec
LOCAL cResponseStatusLine
LOCAL cResponseHeaderLine
LOCAL cRemainderOfHeader

nSuccess := 0

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

oSsh1 := CreateObject("Chilkat.Ssh")

//  Connect directly to the 1st SSH server.
nSuccess := oSsh1:Connect("serverssh1.com", 22)
IF (nSuccess != 1)
    ? oSsh1:LastErrorText
    oSsh1:destroy()
    RETURN
ENDIF

//  Authenticate using login/password:
nSuccess := oSsh1:AuthenticatePw("ssh1Login", "ssh1Password")
IF (nSuccess != 1)
    ? oSsh1:LastErrorText
    oSsh1:destroy()
    RETURN
ENDIF

//  Connect through the 1st SSH connection to reach a 2nd SSH server.
//  Note: Any number of SSH connections may be simultaneously tunneled through a single
//  existing SSH connection.
oSsh2 := CreateObject("Chilkat.Ssh")
nSuccess := oSsh2:ConnectThroughSsh(oSsh1, "serverssh2.com", 22)
IF (nSuccess != 1)
    ? oSsh2:LastErrorText
    oSsh1:destroy()
    oSsh2:destroy()
    RETURN
ENDIF

//  Authenticate with ssh2...
nSuccess := oSsh2:AuthenticatePw("ssh2Login", "ssh2Password")
IF (nSuccess != 1)
    ? oSsh2:LastErrorText
    oSsh1:destroy()
    oSsh2:destroy()
    RETURN
ENDIF

oSocket := CreateObject("Chilkat.Socket")

//  Tell the socket object to connect to our destination server though the ssh2 tunnel (which itself is routed through ssh1).
//  The connection looks like this:  ApplicationSocket(TLS) => ServerSSH1 => ServerSSH2 => DestinationServer
nSuccess := oSocket:UseSsh(oSsh2)
IF (nSuccess != 1)
    ? oSocket:LastErrorText
    oSsh1:destroy()
    oSsh2:destroy()
    oSocket:destroy()
    RETURN
ENDIF

//  Connect using TLS to www.chilkatsoft.com
//  We could also tunnel a bare TCP connection by specifying port 80 with useTls = 0.
nUseTls := 1
nMaxWaitMillisec := 20000
nSuccess := oSocket:Connect("www.chilkatsoft.com", 443, nUseTls, nMaxWaitMillisec)
IF (nSuccess != 1)
    ? oSocket:LastErrorText
    oSsh1:destroy()
    oSsh2:destroy()
    oSocket:destroy()
    RETURN
ENDIF

//  Once the multiple hop SSH tunneled connection is setup,  the socket programming
//  is identical to the normal case where we have a direct connection.

//  Tell the socket object that all text is to be sent in the utf-8 encoding,
//  and the text received is assumed to be utf-8.
oSocket:StringCharset := "utf-8"

//  Send an HTTP HEAD request:
nSuccess := oSocket:SendString("HEAD / HTTP/1.1" + Chr(13) + Chr(10) + "Host: www.chilkatsoft.com" + Chr(13) + Chr(10) + Chr(13) + Chr(10))
IF (nSuccess != 1)
    ? oSocket:LastErrorText
    oSsh1:destroy()
    oSsh2:destroy()
    oSocket:destroy()
    RETURN
ENDIF

//  Wait a maximum of 4 seconds while no data is forthcoming:
oSocket:MaxReadIdleMs := 4000

//  Get the 1st response line, which should be "HTTP/1.1 200 OK"
cResponseStatusLine := oSocket:ReceiveToCRLF()
IF (oSocket:LastMethodSuccess != 1)
    ? oSocket:LastErrorText
    oSsh1:destroy()
    oSsh2:destroy()
    oSocket:destroy()
    RETURN
ENDIF

? "StatusLine: " + cResponseStatusLine

//  Now get the 1st line of the response header:
cResponseHeaderLine := oSocket:ReceiveToCRLF()
IF (oSocket:LastMethodSuccess != 1)
    ? oSocket:LastErrorText
    oSsh1:destroy()
    oSsh2:destroy()
    oSocket:destroy()
    RETURN
ENDIF

? "HeaderLine: " + cResponseHeaderLine

//  Now read the remainder of the response header by reading until a double CRLF is seen:
cRemainderOfHeader := oSocket:ReceiveUntilMatch(Chr(13) + Chr(10) + Chr(13) + Chr(10))
IF (oSocket:LastMethodSuccess != 1)
    ? oSocket:LastErrorText
    oSsh1:destroy()
    oSsh2:destroy()
    oSocket:destroy()
    RETURN
ENDIF

? "Remainder: " + cRemainderOfHeader

//  Close the connection with the server.  This closes the tunnel through ssh2.
//  Wait a max of 20 seconds (20000 millsec)
nSuccess := oSocket:Close(20000)

//  Close the connection with ssh2.  (This closes the the tunnel through ssh1.)
//  The connection with ssh1 is still alive, and may be used for more connections.
oSsh2:Disconnect()

oSsh1:Disconnect()

oSsh1:destroy()
oSsh2:destroy()
oSocket:destroy()