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Hi guysssss, have you ever heard of STUN?! No? When you are under a NAT and you try to connect to an online server, you make the request using an internal port and your local IP. But when your request arrives to the router, it uses its own port list and it enstablishes the connection to the final server using a different port (which has a different port number, but it is associated to your internal port) and the public (external) IP. So, the server responds to your request using the couple external IP\port assigned by the router. Well, STUN is a protocol that permits you to know your external IP but, more interesting, your external port associated to your internal port. But, which is the point? Client/Server connections don't require to know these informations, but what about P2P connection? STUN UDF is the second step (the first was my winsock UDF, which is used in this script) to UDP Hole Punching technique: Here you are the function: ; #FUNCTION# ======================================================================================================================== ; Name...........: _STUN ; Description ...: Makes a STUN request and processes the response ; Syntax.........: _STUN($iLocalPort, $iStunServer = "", $iStunPort = "") ; Parameters ....: $iLocalPort - The local port to be tested ; |1 : 65535 ; $iStunServer - name of the STUN server [Default = ""] ; $iStunPort - STUN server port, used only if $iStunServer <> "" ; |1 : 65535 - [Default = 3478] ; Return values .: On success it returns an array: ; |[0] - The external IP address ; |[1] - The external port ; On failure it returns -1 and sets @error to non zero: ; |-1 - internal error ; |-2 - missing DLL (Ws2_32.dll) ; |-3 - Unable to connect to internet ; |-4 - $iLocalPort is not a valid port ; |-5 - can't bind to $iLocalPort, try a different port ; |-6 - problem with servers ; Remarks .......: This function is used by a client to know which external port/IP correspond to the indicated internal port. ; By default it is used a STUN server list composed by: ; stun.l.google.com:19302, stun1.l.google.com:19302, stun.ekiga.net:3478, stun.ideasip.com:3478, stun.schlund.de:3478 ; If $iStunServer is indicated, the first element of the list is replaced by $iStunServer:$iStunPort ; Author ........: j0kky ; Modified ......: 1.0.0 ; Links .........: STUN RFC 5389: https://tools.ietf.org/html/rfc5389 ; ==================================================================================================================================== #include "winsock.au3" Func _STUN($iLocalPort, $iStunServer = "", $iStunPort = "") $iLocalPort = Int($iLocalPort) If ($iLocalPort < 1) Or ($iLocalPort > 65535) Then Return SetError(-4, 0, -1) $iExtended = 0 If $iStunServer = Default Then $iStunServer = "" $iStunServer = String($iStunServer) If $iStunServer Then $iStunServer = StringRegExpReplace($iStunServer, "^http.?://", "") If StringRight($iStunServer, 1) = "/" Then $iStunServer = StringTrimRight($iStunServer, 1) If Not StringRegExp($iStunServer, ".+\..{2,}") Then $iStunServer = "" ; invalid parameter $iExtended = -1 EndIf EndIf $hWs2 = DllOpen("Ws2_32.dll") If @error Then Return SetError(-2, $iExtended, -1) $tHeader = DllStructCreate("ushort MessageType; ushort MessageLenght; ulong MagicCookie; byte TransactionID[12]") $aRet = DllCall($hWs2, "ushort", "htons", "ushort", 0x0001) If @error Then DllClose($hWs2) Return SetError(-1, $iExtended, -1) Else DllStructSetData($tHeader, "MessageType", $aRet[0]) ;MessageType EndIf DllStructSetData($tHeader, "MessageLenght", 0x0000) ;MessageLenght $aRet = DllCall($hWs2, "ulong", "htonl", "ulong", 0x2112A442) If @error Then DllClose($hWs2) Return SetError(-1, $iExtended, -1) Else DllStructSetData($tHeader, "MagicCookie", $aRet[0]) ;MagicCookie EndIf For $i = 1 To 12 DllStructSetData($tHeader, "TransactionID", Random(0x00, 0xff, 1), $i) ;TransactionID Next _UDPStartup() If @error Then DllClose($hWs2) Return SetError(-1, $iExtended, -1) EndIf $sLocalIP = _GetIPs() If @error Then _UDPShutdown() DllClose($hWs2) Return SetError(-3, $iExtended, -1) EndIf $sLocalIP = $sLocalIP[0] If $iStunServer Then $sFirstServer = $iStunServer If $iStunPort Then $nFirstPort = $iStunPort Else $nFirstPort = 3478 EndIf Else $sFirstServer = "stun.l.google.com" $nFirstPort = 19302 EndIf Local $aStunServer[5][2] = [[$sFirstServer, $nFirstPort], ["stun1.l.google.com", 19302], ["stun.ekiga.net", 3478], ["stun.ideasip.com", 3478], ["stun.schlund.de", 3478]] $nBindSocket = _UDPBind($sLocalIP, $iLocalPort) If @error Then Return SetError(-5, $iExtended, -1) For $j = 0 To 4 $iError = 0 $sServerName = $aStunServer[$j][0] $sServerIP = _TCPNameToIP($sServerName) If @error Then $iError = -6 If Not $iError Then ;RFC indicates that $nRcMaxValue should be equal to 7 and $nRm should be equal to 16, ;but, following those rules, if the server doesn't respond quickly, the script is blocked for more than 1 minute $tByteHeader = DllStructCreate("byte[" & DllStructGetSize($tHeader) & "]", DllStructGetPtr($tHeader)) Local $nRTO = 500, $hTime = TimerInit(), $nRTOTotal = 0, $nRc = 0, $nRcMaxValue = 2, $aRecv = "", $nRm = 2 Do If ($nRc < $nRcMaxValue) And (TimerDiff($hTime) >= $nRTOTotal) Then _UDPSendTo($sServerIP, $aStunServer[$j][1], DllStructGetData($tByteHeader, 1), $nBindSocket) If @error Then $iError = -1 $nRTOTotal += $nRTO * (2 ^ $nRc) $nRc += 1 If $nRc = $nRcMaxValue Then $hTime = TimerInit() EndIf $aRecv = _UDPRecvFrom($nBindSocket, 2048, 1) If @error Then $iError = -1 Sleep(100) Until ($aRecv <> -1) Or (($nRc = $nRcMaxValue) And (TimerDiff($hTime) >= $nRTO * $nRm)) If Not IsArray($aRecv) Then $iError = -1 EndIf If Not $iError Then $dResponse = $aRecv[0] $aRet = DllCall($hWs2, "ushort", "ntohs", "ushort", BinaryMid($dResponse, 3, 2)) ;MessageLenght If @error Then $iError = -1 Else $nMessageLenght = $aRet[0] EndIf If Not ($nMessageLenght > 0) Then $iError = -6 EndIf If Not $iError Then $dResponse = BinaryMid($dResponse, 1, $nMessageLenght + 20) ;message lenght plus header size $aRet = DllCall($hWs2, "ushort", "ntohs", "ushort", BinaryMid($dResponse, 1, 2)) ;MessageType If @error Then $iError = -1 Else $nMessageType = $aRet[0] If Not (($nMessageType = 0x0101) Or ($nMessageType = 0x0111)) Then $iError = -6 EndIf EndIf If Not $iError Then $nByteNumber = 1 If $nMessageType = 0x0101 Then ;Binding success response Do $iError = 0 $aRet = DllCall($hWs2, "ushort", "ntohs", "ushort", BinaryMid($dResponse, 20 + $nByteNumber, 2)) ;Attribute Type If @error Then $iError = -1 Else $nAttributeType = $aRet[0] EndIf If Not $iError And (($nAttributeType = 0x0001) Or ($nAttributeType = 0x0020)) Then ;MAPPED-ADDRESS or XOR-MAPPED-ADDRESS $aRet = DllCall($hWs2, "ushort", "ntohs", "ushort", BinaryMid($dResponse, 24 + $nByteNumber, 2)) ;Family If @error Then $iError = -1 Else $nFamily = $aRet[0] EndIf EndIf If Not $iError Then Local $aResult[2] If $nAttributeType = 0x0020 Then ;XOR-MAPPED-ADDRESS $aRet = DllCall($hWs2, "ushort", "ntohs", "ushort", BinaryMid($dResponse, 26 + $nByteNumber, 2)) ;Port If @error Then $iError = -1 Else $aResult[1] = BitXOR($aRet[0], 0x2112) ;Xored with the most significant 16 bit of Magic Cookie EndIf If Not $iError Then If $nFamily = 0x0001 Then ;IPv4 $dNBOIP = BinaryMid($dResponse, 28 + $nByteNumber, 4) $dNBOCookie = Binary("0x" & Hex(0x2112A442)) $tNBOXoredIP = DllStructCreate("byte[4]") For $i = 1 To 4 DllStructSetData($tNBOXoredIP, 1, BitXOR(BinaryMid($dNBOIP, $i, 1), BinaryMid($dNBOCookie, $i, 1)), $i) Next $aRet = DllCall($hWs2, "ptr", "inet_ntoa", "ulong", Int(DllStructGetData($tNBOXoredIP, 1))) If @error Then $iError = -1 ElseIf $aRet[0] = Null Then $iError = -6 Else $aResult[0] = DllStructGetData(DllStructCreate("char[15]", $aRet[0]), 1) ;IP address xored with Magic Cookie EndIf Else ;IPv6 $dNBOIP = BinaryMid($dResponse, 28 + $nByteNumber, 16) $dNBOConcatenation = BinaryMid($dResponse, 5, 16) $tNBOXoredIP = DllStructCreate("byte[16]") For $i = 1 To 16 DllStructSetData($tNBOXoredIP, 1, BitXOR(BinaryMid($dNBOIP, $i, 1), BinaryMid($dNBOConcatenation, $i, 1)), $i) Next $tIP = DllStructCreate("char[46]") $aRet = DllCall($hWs2, "ptr", "inet_ntop", _ "int", 23, "ptr", DllStructGetPtr($tNBOXoredIP), "ptr", DllStructGetPtr($tIP), "ULONG_PTR", DllStructGetSize($tIP)) If @error Then $iError = -1 ElseIf $aRet[0] = Null Then $iError = -6 Else $aResult[0] = DllStructGetData($tIP, 1) ;IP address EndIf EndIf EndIf ExitLoop 2 ElseIf $nAttributeType = 0x0001 Then ;MAPPED-ADDRESS $aRet = DllCall($hWs2, "ushort", "ntohs", "ushort", BinaryMid($dResponse, 26 + $nByteNumber, 2)) ;Port If @error Then $iError = -1 Else $aResult[1] = $aRet[0] EndIf If Not $iError Then If $nFamily = 0x0001 Then ;IPv4 $aRet = DllCall($hWs2, "ptr", "inet_ntoa", "ulong", BinaryMid($dResponse, 28 + $nByteNumber, 4)) If @error Then $iError = -1 ElseIf $aRet[0] = Null Then $iError = -6 Else $aResult[0] = DllStructGetData(DllStructCreate("char[15]", $aRet[0]), 1) ;IP address EndIf Else ;IPv6 $tNBOIP = DllStructCreate("byte[16]") DllStructSetData($tNBOIP, 1, BinaryMid($dResponse, 28 + $nByteNumber, 16)) $tIP = DllStructCreate("char[46]") $aRet = DllCall($hWs2, "ptr", "inet_ntop", _ "int", 23, "ptr", DllStructGetPtr($tNBOIP), "ptr", DllStructGetPtr($tIP), "ULONG_PTR", DllStructGetSize($tIP)) If @error Then $iError = -1 ElseIf $aRet[0] = Null Then $iError = -6 Else $aResult[0] = DllStructGetData($tIP, 1) ;IP address EndIf EndIf EndIf ExitLoop 2 Else $aRet = DllCall($hWs2, "ushort", "ntohs", "ushort", BinaryMid($dResponse, 22 + $nByteNumber, 2)) ;Attribute Lenght If @error Then $iError = -1 Else $nAttributeLenght = $aRet[0] If Not (Mod($nAttributeLenght, 4) = 0) Then $nAttributeLenght += 4 - Mod($nAttributeLenght, 4) ;padding $nByteNumber += 4 + $nAttributeLenght ;TLV EndIf EndIf EndIf Until $nByteNumber > $nMessageLenght Else ;0x0111 = Binding error response $iError = -6 EndIf EndIf Next _UDPCloseSocket($nBindSocket) _UDPShutdown() DllClose($hWs2) If $iError Then $aResult = -1 If $iStunServer And ($iStunServer <> $sServerName) Then $iExtended = -2 Return SetError($iError, $iExtended, $aResult) EndFunc ;==>_STUN Please test it (especially if you have an IPv6 interface) and report every bug you can try STUN.zip