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How Server can connect to client over the internet with tcp

AlexFing17
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AlexFing17 Seeker

AlexFing17

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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 

#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 

#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 Universalist

spudw2k

Posted
Posted

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.)

Spoiler

Things I've Made: Always On Top Tool ◊ AU History ◊ Deck of Cards ◊ HideIt ◊ ICU ◊ Icon Freezer ◊ Ipod Ejector ◊ Junos Configuration Explorer ◊ Link Downloader ◊ MD5 Folder Enumerator ◊ PassGen ◊ Ping Tool ◊ Quick NIC ◊ Read OCR ◊ RemoteIT ◊ SchTasksGui ◊ SpyCam ◊ System Scan Report Tool ◊ System UpTime ◊ Transparency Machine ◊ VMWare ESX Builder
Misc Code Snippets: ADODB Example ◊ CheckHover ◊ Detect SafeMode ◊ DynEnumArray ◊ GetNetStatData ◊ HashArray ◊ IsBetweenDates ◊ Local Admins ◊ Make Choice ◊ Recursive File List ◊ Remove Sizebox Style ◊ Retrieve PNPDeviceID ◊ Retrieve SysListView32 Contents ◊ Set IE Homepage ◊ Tickle Expired Password ◊ Transpose Array
Projects: Drive Space Usage GUI ◊ LEDkIT ◊ Plasma_kIt ◊ Scan Engine Builder ◊ SpeeDBurner ◊ SubnetCalc
Cool Stuff: AutoItObject UDF ◊ Extract Icon From Proc ◊ GuiCtrlFontRotate ◊ Hex Edit Funcs ◊ Run binary ◊ Service_UDF

 

AlexFing17 Seeker

AlexFing17

Posted
  • Author
Posted
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 Seeker

AlexFing17

Posted
  • Author
Posted
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 Universalist

spudw2k

Posted
Posted

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).

 

Spoiler

Things I've Made: Always On Top Tool ◊ AU History ◊ Deck of Cards ◊ HideIt ◊ ICU ◊ Icon Freezer ◊ Ipod Ejector ◊ Junos Configuration Explorer ◊ Link Downloader ◊ MD5 Folder Enumerator ◊ PassGen ◊ Ping Tool ◊ Quick NIC ◊ Read OCR ◊ RemoteIT ◊ SchTasksGui ◊ SpyCam ◊ System Scan Report Tool ◊ System UpTime ◊ Transparency Machine ◊ VMWare ESX Builder
Misc Code Snippets: ADODB Example ◊ CheckHover ◊ Detect SafeMode ◊ DynEnumArray ◊ GetNetStatData ◊ HashArray ◊ IsBetweenDates ◊ Local Admins ◊ Make Choice ◊ Recursive File List ◊ Remove Sizebox Style ◊ Retrieve PNPDeviceID ◊ Retrieve SysListView32 Contents ◊ Set IE Homepage ◊ Tickle Expired Password ◊ Transpose Array
Projects: Drive Space Usage GUI ◊ LEDkIT ◊ Plasma_kIt ◊ Scan Engine Builder ◊ SpeeDBurner ◊ SubnetCalc
Cool Stuff: AutoItObject UDF ◊ Extract Icon From Proc ◊ GuiCtrlFontRotate ◊ Hex Edit Funcs ◊ Run binary ◊ Service_UDF

 

AlexFing17 Seeker

AlexFing17

Posted
  • Author
Posted
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.

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