How Server can connect to client over the internet with tcp

[AlexFing17]

i am trying to figure out how a server can connect to a client Over the internet. 

In this is script. The client connects to the server on the same machine (localhost) and executes the commands from the client.

How can I change that instead communicating over localhost to communicate over the internet with tcp ipaddress and a port.

 

What i actually need help of is

1. The server will open a port and  listen to communication from a No-ip address

2. I input the no-ip address and correct port in the client side, and when i click on connect, it connects to the server if its online

 

 

This is the client

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#include <GuiConstantsEx.au3>
THIS IS THE CLIENT

#include <NamedPipes.au3>
#include <StaticConstants.au3>
#include <WinAPI.au3>
#include <WindowsConstants.au3>

; ===============================================================================================================================
; Description ...: This is the client side of the pipe demo
; Author ........: Paul Campbell (PaulIA)
; Notes .........:
; ===============================================================================================================================

; ===============================================================================================================================
; Global constants
; ===============================================================================================================================

Global Const $BUFSIZE = 4096
Global Const $DEFCMD = "cmd.exe /c dir c:\"
Global Const $PIPE_NAME = "\\$\\pipe\\AutoIt3"
Global Const $ERROR_MORE_DATA = 234

; ===============================================================================================================================
; Global variables
; ===============================================================================================================================

Global $g_idEdit, $g_idMemo, $g_idSend, $g_idServer, $g_hPipe

; ===============================================================================================================================
; Main
; ===============================================================================================================================

CreateGUI()
MsgLoop()

; ===============================================================================================================================
; Creates a GUI for the client
; ===============================================================================================================================
Func CreateGUI()
    Local $hGUI = GUICreate("FarC0nn3c7", 500, 400, -1, -1, $WS_SIZEBOX)
    GUICtrlCreateLabel("Server:", 2, 14, 52, 20, $SS_RIGHT)
    $g_idServer = GUICtrlCreateEdit("<local>", 56, 10, 200, 20, $SS_LEFT)
    GUICtrlCreateLabel("Command:", 2, 36, 52, 20, $SS_RIGHT)
    $g_idEdit = GUICtrlCreateEdit($DEFCMD, 56, 32, 370, 20, $SS_LEFT)
    $g_idSend = GUICtrlCreateButton("Pawn Dem", 430, 32, 60, 20)
    $g_idMemo = GUICtrlCreateEdit("", 0, 62, _WinAPI_GetClientWidth($hGUI), 332)
    GUICtrlSetFont($g_idMemo, 9, 400, 0, "Courier New")
    GUISetState()
EndFunc   ;==>CreateGUI

; ===============================================================================================================================
; Logs an error message to the display
; ===============================================================================================================================
Func LogError($sMessage)
    $sMessage &= " (" & _WinAPI_GetLastErrorMessage() & ")"
    GUICtrlSetData($g_idMemo, GUICtrlRead($g_idMemo) & $sMessage & @CRLF)
EndFunc   ;==>LogError

; ===============================================================================================================================
; Logs a message to the display
; ===============================================================================================================================
Func LogMsg($sMessage)
    GUICtrlSetData($g_idMemo, GUICtrlRead($g_idMemo) & $sMessage & @CRLF)
EndFunc   ;==>LogMsg

; ===============================================================================================================================
; MsgLoop
; ===============================================================================================================================
Func MsgLoop()
    While True
        Switch GUIGetMsg()
            Case $g_idSend
                SendCmd()
            Case $GUI_EVENT_CLOSE
                Exit
        EndSwitch
    WEnd
EndFunc   ;==>MsgLoop

; ===============================================================================================================================
; This function opens a pipe to the server
; ===============================================================================================================================
Func OpenPipe()
    Local $sName, $sPipe
    ; Get pipe handle
    $sName = GUICtrlRead($g_idServer)
    If $sName = "<local>" Then $sName = "."
    $sPipe = StringReplace($PIPE_NAME, "$", $sName)
    $g_hPipe = _WinAPI_CreateFile($sPipe, 2, 6)
    If $g_hPipe <> -1 Then Return True
    LogError("OpenPipe failed")
    Return False
EndFunc   ;==>OpenPipe

; ===============================================================================================================================
; This function reads a message from the pipe
; ===============================================================================================================================
Func ReadMsg()
    Local $bSuccess, $iRead, $pBuffer, $tBuffer

    $tBuffer = DllStructCreate("char Text[4096]")
    $pBuffer = DllStructGetPtr($tBuffer)
    GUICtrlSetData($g_idMemo, "")
    While 1
        $bSuccess = _WinAPI_ReadFile($g_hPipe, $pBuffer, $BUFSIZE, $iRead, 0)
        If $iRead = 0 Then ExitLoop
        If Not $bSuccess Or (_WinAPI_GetLastError() = $ERROR_MORE_DATA) Then ExitLoop
        GUICtrlSetData($g_idMemo, StringLeft(DllStructGetData($tBuffer, "Text"), $iRead), 1)
    WEnd
EndFunc   ;==>ReadMsg

; ===============================================================================================================================
; This function sends a command to the server
; ===============================================================================================================================
Func SendCmd()
    If OpenPipe() Then
        SetReadMode()
        WriteMsg(GUICtrlRead($g_idEdit))
        ReadMsg()
        _WinAPI_CloseHandle($g_hPipe)
    EndIf
EndFunc   ;==>SendCmd

; ===============================================================================================================================
; This function sets the pipe read mode
; ===============================================================================================================================
Func SetReadMode()
    If Not _NamedPipes_SetNamedPipeHandleState($g_hPipe, 1, 0, 0, 0) Then
        LogError("SetReadMode: _NamedPipes_SetNamedPipeHandleState failed")
    EndIf
EndFunc   ;==>SetReadMode

; ===============================================================================================================================
; This function writes a message to the pipe
; ===============================================================================================================================
Func WriteMsg($sMessage)
    Local $iWritten, $iBuffer, $pBuffer, $tBuffer

    $iBuffer = StringLen($sMessage) + 1
    $tBuffer = DllStructCreate("char Text[" & $iBuffer & "]")
    $pBuffer = DllStructGetPtr($tBuffer)
    DllStructSetData($tBuffer, "Text", $sMessage)
    If Not _WinAPI_WriteFile($g_hPipe, $pBuffer, $iBuffer, $iWritten, 0) Then
        LogError("WriteMsg: _WinAPI_WriteFile failed")
    EndIf
EndFunc   ;==>WriteMsg

Spoiler

 

 

And this is the server

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#include <GuiConstantsEx.au3>
#include <NamedPipes.au3>
#include <WinAPI.au3>
#include <WindowsConstants.au3>
#NoTrayIcon
; ===============================================================================================================================
; Description ...: This is the server side of the pipe demo
; Author ........: Paul Campbell (PaulIA)
; Notes .........:
; ===============================================================================================================================

; ===============================================================================================================================
; Global constants
; ===============================================================================================================================

Global Const $DEBUGGING = False
Global Const $BUFSIZE = 4096
Global Const $PIPE_NAME = "\\.\\pipe\\AutoIt3"
Global Const $TIMEOUT = 5000
Global Const $WAIT_TIMEOUT = 258
Global Const $ERROR_IO_PENDING = 997
Global Const $ERROR_PIPE_CONNECTED = 535

; ===============================================================================================================================
; Global variables
; ===============================================================================================================================

Global $g_hEvent, $g_idMemo, $g_pOverlap, $g_tOverlap, $g_hPipe, $g_hReadPipe, $g_iState, $g_iToWrite

; ===============================================================================================================================
; Main
; ===============================================================================================================================

CreateGUI()
InitPipe()
MsgLoop()

; ===============================================================================================================================
; Creates a GUI for the server
; ===============================================================================================================================
Func CreateGUI()

    Local $hGUI

    $hGUI = GUICreate("Pipe Server", 500, 400, -1, -1, $WS_SIZEBOX)
    $g_idMemo = GUICtrlCreateEdit("", 0, 0, _WinAPI_GetClientWidth($hGUI), _WinAPI_GetClientHeight($hGUI))
    GUICtrlSetFont($g_idMemo, 9, 400, 0, "Courier New")
    GUISetState()
EndFunc   ;==>CreateGUI

; ===============================================================================================================================
; This function creates an instance of a named pipe
; ===============================================================================================================================
Func InitPipe()
    ; Create an event object for the instance
    $g_tOverlap = DllStructCreate($tagOVERLAPPED)
    $g_pOverlap = DllStructGetPtr($g_tOverlap)
    $g_hEvent = _WinAPI_CreateEvent()
    If $g_hEvent = 0 Then
        LogError("InitPipe ..........: API_CreateEvent failed")
        Return
    EndIf
    DllStructSetData($g_tOverlap, "hEvent", $g_hEvent)

    ; Create a named pipe
    $g_hPipe = _NamedPipes_CreateNamedPipe($PIPE_NAME, _ ; Pipe name
            2, _ ; The pipe is bi-directional
            2, _ ; Overlapped mode is enabled
            0, _ ; No security ACL flags
            1, _ ; Data is written to the pipe as a stream of messages
            1, _ ; Data is read from the pipe as a stream of messages
            0, _ ; Blocking mode is enabled
            1, _ ; Maximum number of instances
            $BUFSIZE, _ ; Output buffer size
            $BUFSIZE, _ ; Input buffer size
            $TIMEOUT, _ ; Client time out
            0) ; Default security attributes
    If $g_hPipe = -1 Then
        LogError("InitPipe ..........: _NamedPipes_CreateNamedPipe failed")
    Else
        ; Connect pipe instance to client
        ConnectClient()
    EndIf
EndFunc   ;==>InitPipe

; ===============================================================================================================================
; This function loops waiting for a connection event or the GUI to close
; ===============================================================================================================================
Func MsgLoop()
    Local $iEvent

    Do
        $iEvent = _WinAPI_WaitForSingleObject($g_hEvent, 0)
        If $iEvent < 0 Then
            LogError("MsgLoop ...........: _WinAPI_WaitForSingleObject failed")
            Exit
        EndIf
        If $iEvent = $WAIT_TIMEOUT Then ContinueLoop
        Debug("MsgLoop ...........: Instance signaled")

        Switch $g_iState
            Case 0
                CheckConnect()
            Case 1
                ReadRequest()
            Case 2
                CheckPending()
            Case 3
                RelayOutput()
        EndSwitch
    Until GUIGetMsg() = $GUI_EVENT_CLOSE
EndFunc   ;==>MsgLoop

; ===============================================================================================================================
; Checks to see if the pending client connection has finished
; ===============================================================================================================================
Func CheckConnect()
    Local $iBytes

    ; Was the operation successful?
    If Not _WinAPI_GetOverlappedResult($g_hPipe, $g_pOverlap, $iBytes, False) Then
        LogError("CheckConnect ......: Connection failed")
        ReconnectClient()
    Else

        $g_iState = 1
    EndIf
EndFunc   ;==>CheckConnect

; ===============================================================================================================================
; This function reads a request message from the client
; ===============================================================================================================================
Func ReadRequest()
    Local $pBuffer, $tBuffer, $iRead, $bSuccess

    $tBuffer = DllStructCreate("char Text[" & $BUFSIZE & "]")
    $pBuffer = DllStructGetPtr($tBuffer)
    $bSuccess = _WinAPI_ReadFile($g_hPipe, $pBuffer, $BUFSIZE, $iRead, $g_pOverlap)

    If $bSuccess And ($iRead <> 0) Then
        ; The read operation completed successfully
        Debug("ReadRequest .......: Read success")
    Else
        ; Wait for read Buffer to complete
        If Not _WinAPI_GetOverlappedResult($g_hPipe, $g_pOverlap, $iRead, True) Then
            LogError("ReadRequest .......: _WinAPI_GetOverlappedResult failed")
            ReconnectClient()
            Return
        Else
            ; Read the command from the pipe
            $bSuccess = _WinAPI_ReadFile($g_hPipe, $pBuffer, $BUFSIZE, $iRead, $g_pOverlap)
            If Not $bSuccess Or ($iRead = 0) Then
                LogError("ReadRequest .......: _WinAPI_ReadFile failed")
                ReconnectClient()
                Return
            EndIf
        EndIf
    EndIf

    ; Execute the console command
    If Not ExecuteCmd(DllStructGetData($tBuffer, "Text")) Then
        ReconnectClient()
        Return
    EndIf

    ; Relay console output back to the client
    $g_iState = 3
EndFunc   ;==>ReadRequest

; ===============================================================================================================================
; This function relays the console output back to the client
; ===============================================================================================================================
Func CheckPending()
    Local $bSuccess, $iWritten

    $bSuccess = _WinAPI_GetOverlappedResult($g_hPipe, $g_pOverlap, $iWritten, False)
    If Not $bSuccess Or ($iWritten <> $g_iToWrite) Then
        Debug("CheckPending ......: Write reconnecting")
        ReconnectClient()
    Else
        Debug("CheckPending ......: Write complete")
        $g_iState = 3
    EndIf
EndFunc   ;==>CheckPending

; ===============================================================================================================================
; This function relays the console output back to the client
; ===============================================================================================================================
Func RelayOutput()
    Local $pBuffer, $tBuffer, $sLine, $iRead, $bSuccess, $iWritten

    $tBuffer = DllStructCreate("char Text[" & $BUFSIZE & "]")
    $pBuffer = DllStructGetPtr($tBuffer)
    ; Read data from console pipe
    _WinAPI_ReadFile($g_hReadPipe, $pBuffer, $BUFSIZE, $iRead)
    If $iRead = 0 Then
        LogMsg("RelayOutput .......: Write done")
        _WinAPI_CloseHandle($g_hReadPipe)
        _WinAPI_FlushFileBuffers($g_hPipe)
        ReconnectClient()
        Return
    EndIf

    ; Get the data and strip out the extra carriage returns
    $sLine = StringLeft(DllStructGetData($tBuffer, "Text"), $iRead)
    $sLine = StringReplace($sLine, @CR & @CR, @CR)
    $g_iToWrite = StringLen($sLine)
    DllStructSetData($tBuffer, "Text", $sLine)
    ; Relay the data back to the client
    $bSuccess = _WinAPI_WriteFile($g_hPipe, $pBuffer, $g_iToWrite, $iWritten, $g_pOverlap)
    If $bSuccess And ($iWritten = $g_iToWrite) Then
        Debug("RelayOutput .......: Write success")
    Else
        If Not $bSuccess And (_WinAPI_GetLastError() = $ERROR_IO_PENDING) Then
            Debug("RelayOutput .......: Write pending")
            $g_iState = 2
        Else
            ; An error occurred, disconnect from the client
            LogError("RelayOutput .......: Write failed")
            ReconnectClient()
        EndIf
    EndIf
EndFunc   ;==>RelayOutput

; ===============================================================================================================================
; This function is called to start an overlapped connection operation
; ===============================================================================================================================
Func ConnectClient()
    $g_iState = 0
    ; Start an overlapped connection
    If _NamedPipes_ConnectNamedPipe($g_hPipe, $g_pOverlap) Then
        LogError("ConnectClient .....: ConnectNamedPipe 1 failed")
    Else
        Switch @error
            ; The overlapped connection is in progress
            Case $ERROR_IO_PENDING
                Debug("ConnectClient .....: Pending")
                ; Client is already connected, so signal an event
            Case $ERROR_PIPE_CONNECTED
                LogMsg("ConnectClient .....: Connected")
                $g_iState = 1
                If Not _WinAPI_SetEvent(DllStructGetData($g_tOverlap, "hEvent")) Then
                    LogError("ConnectClient .....: SetEvent failed")
                EndIf
                ; Error occurred during the connection event
            Case Else
                LogError("ConnectClient .....: ConnectNamedPipe 2 failed")
        EndSwitch
    EndIf
EndFunc   ;==>ConnectClient

; ===============================================================================================================================
; Dumps debug information to the screen
; ===============================================================================================================================
Func Debug($sMessage)
    If $DEBUGGING Then LogMsg($sMessage)
EndFunc   ;==>Debug

; ===============================================================================================================================
; Executes a command and returns the results
; ===============================================================================================================================
Func ExecuteCmd($sCmd)
    Local $tProcess, $tSecurity, $tStartup, $hWritePipe

    ; Set up security attributes
    $tSecurity = DllStructCreate($tagSECURITY_ATTRIBUTES)
    DllStructSetData($tSecurity, "Length", DllStructGetSize($tSecurity))
    DllStructSetData($tSecurity, "InheritHandle", True)

    ; Create a pipe for the child process's STDOUT
    If Not _NamedPipes_CreatePipe($g_hReadPipe, $hWritePipe, $tSecurity) Then
        LogError("ExecuteCmd ........: _NamedPipes_CreatePipe failed")
        Return False
    EndIf

    ; Create child process
    $tProcess = DllStructCreate($tagPROCESS_INFORMATION)
    $tStartup = DllStructCreate($tagSTARTUPINFO)
    DllStructSetData($tStartup, "Size", DllStructGetSize($tStartup))
    DllStructSetData($tStartup, "Flags", BitOR($STARTF_USESTDHANDLES, $STARTF_USESHOWWINDOW))
    DllStructSetData($tStartup, "StdOutput", $hWritePipe)
    DllStructSetData($tStartup, "StdError", $hWritePipe)
    If Not _WinAPI_CreateProcess("", $sCmd, 0, 0, True, 0, 0, "", DllStructGetPtr($tStartup), DllStructGetPtr($tProcess)) Then
        LogError("ExecuteCmd ........: _WinAPI_CreateProcess failed")
        _WinAPI_CloseHandle($g_hReadPipe)
        _WinAPI_CloseHandle($hWritePipe)
        Return False
    EndIf
    _WinAPI_CloseHandle(DllStructGetData($tProcess, "hProcess"))
    _WinAPI_CloseHandle(DllStructGetData($tProcess, "hThread"))

    ; Close the write end of the pipe so that we can read from the read end
    _WinAPI_CloseHandle($hWritePipe)

    LogMsg("ExecuteCommand ....: " & $sCmd)
    Return True
EndFunc   ;==>ExecuteCmd

; ===============================================================================================================================
; Logs an error message to the display
; ===============================================================================================================================
Func LogError($sMessage)
    $sMessage &= " (" & _WinAPI_GetLastErrorMessage() & ")"
    ConsoleWrite($sMessage & @LF)
EndFunc   ;==>LogError


; ===============================================================================================================================
; This function is called when an error occurs or when the client closes its handle to the pipe
; ===============================================================================================================================
Func ReconnectClient()
    ; Disconnect the pipe instance
    If Not _NamedPipes_DisconnectNamedPipe($g_hPipe) Then
        LogError("ReconnectClient ...: DisonnectNamedPipe failed")
        Return
    EndIf

    ; Connect to a new client
    ConnectClient()
EndFunc   ;==>ReconnectClient

 

[spudw2k]

So, the major issue here is going to be whether or not the server IP and port are in fact internet accessible.  Is the "server" in the cloud/accessible from the internet as far as you know?  If the "server" sits behind a firewall (i.e. via business or home ISP), the firewall will need to be configured to pass traffic to the server (i.e. port forwarding/triggering, DMZ, etc.)

[RTFC]

Look into  "port forwarding"

[AlexFing17]

10 hours ago, spudw2k said:

So, the major issue here is going to be whether or not the server IP and port are in fact internet accessible.  Is the "server" in the cloud/accessible from the internet as far as you know?  If the "server" sits behind a firewall (i.e. via business or home ISP), the firewall will need to be configured to pass traffic to the server (i.e. port forwarding/triggering, DMZ, etc.)

i will configure it to allow it since is my own computer but in my second home.

 

my problem here  is how i can make them connect to each other and receive the commands. 

since the code i posted only allow localhost connection. 

How can i connect from the client to the server with an external ip of the computer the server is installed on.

 

Thank you

[AlexFing17]

4 hours ago, RTFC said:

Look into  "port forwarding"

My problem is how i can make my client connect to the server with the external ip of the computer the server is running on.

 

Thank you

[spudw2k]

Well, you mentioned No-Ip, so you would/could use that to tie your external IP to a Domain Name (URL).   Then it's just a matter of configuring your home router/firewall to do either port forwarding or triggering.

Instead of the period "." (denotes local), you should be able to replace it with an IP or resolvable hostname (Domain Name).

 

[AlexFing17]

On 4/19/2017 at 4:06 PM, spudw2k said:

Well, you mentioned No-Ip, so you would/could use that to tie your external IP to a Domain Name (URL).   Then it's just a matter of configuring your home router/firewall to do either port forwarding or triggering.

Instead of the period "." (denotes local), you should be able to replace it with an IP or resolvable hostname (Domain Name).

 

I want the server to receive connection from only my no ip adrees..

in a the case where

 

1. if the server is running then it waits for remote connection from my no ip address.

2. so i set the no ip address on my computer and runs the client , the server on my home computer will connect back to it automatic if is online.