Dike out some cruft in Windows tap that we will never use, like TUN mode, DHCP masq, ARP emulation, NDP emulation, and related. We operate only in L2 mode. All tap, no tun.

node/EthernetTap.cpp

@@ -867,6 +867,7 @@ EthernetTap::EthernetTap(
 		}
 	}
 
+	// If we have a device, configure it
 	if (_myDeviceInstanceId.length() > 0) {
 		char tmps[4096];
 		unsigned int tmpsl = sprintf_s(tmps,"%.2X-%.2X-%.2X-%.2X-%.2X-%.2X",(unsigned int)mac.data[0],(unsigned int)mac.data[1],(unsigned int)mac.data[2],(unsigned int)mac.data[3],(unsigned int)mac.data[4],(unsigned int)mac.data[5]) + 1;
@@ -878,11 +879,14 @@ EthernetTap::EthernetTap(
 		RegSetKeyValueA(nwAdapters,mySubkeyName.c_str(),"EnableDHCP",REG_DWORD,(LPCVOID)&tmp,sizeof(tmp));
 	}
 
+	// Done with registry
 	RegCloseKey(nwAdapters);	
 
+	// If we didn't get a device, we can't start
 	if (_myDeviceInstanceId.length() == 0)
 		throw std::runtime_error("unable to create new tap adapter");
 
+	// Convert device GUID junk... blech
 	{
 		char nobraces[128];
 		const char *nbtmp1 = _myDeviceInstanceId.c_str();
@@ -897,7 +901,7 @@ EthernetTap::EthernetTap(
 			throw std::runtime_error("unable to convert instance ID GUID to native GUID (invalid NetCfgInstanceId in registry?)");
 	}
 
-	// Disable and enable interface to ensure settings take effect
+	// Disable and enable interface to ensure registry settings take effect
 	{
 		STARTUPINFOA startupInfo;
 		startupInfo.cb = sizeof(startupInfo);
@@ -928,26 +932,24 @@ EthernetTap::EthernetTap(
 	}
 
 	// Open the tap, which is in this weird Windows analog of /dev
-#ifdef UNICODE
-	wchar_t tapPath[4096];
-	swprintf_s(tapPath,L"\\\\.\\Global\\%S.tap",_myDeviceInstanceId.c_str());
-#else
 	char tapPath[4096];
 	sprintf_s(tapPath,"\\\\.\\Global\\%s.tap",_myDeviceInstanceId.c_str());
-#endif
-	_tap = CreateFile(tapPath,GENERIC_READ|GENERIC_WRITE,0,NULL,OPEN_EXISTING,FILE_ATTRIBUTE_SYSTEM|FILE_FLAG_OVERLAPPED,NULL);
+	_tap = CreateFileA(tapPath,GENERIC_READ|GENERIC_WRITE,0,NULL,OPEN_EXISTING,FILE_ATTRIBUTE_SYSTEM|FILE_FLAG_OVERLAPPED,NULL);
 	if (_tap == INVALID_HANDLE_VALUE)
 		throw std::runtime_error("unable to open tap in \\\\.\\Global\\ namespace");
 
+	// Set media status to enabled
 	uint32_t tmpi = 1;
 	DWORD bytesReturned = 0;
 	DeviceIoControl(_tap,TAP_WIN_IOCTL_SET_MEDIA_STATUS,&tmpi,sizeof(tmpi),&tmpi,sizeof(tmpi),&bytesReturned,NULL);
 
+	// Initialized overlapped I/O structures and related events
 	memset(&_tapOvlRead,0,sizeof(_tapOvlRead));
 	_tapOvlRead.hEvent = CreateEvent(NULL,TRUE,FALSE,NULL);
 	memset(&_tapOvlWrite,0,sizeof(_tapOvlWrite));
 	_tapOvlWrite.hEvent = CreateEvent(NULL,TRUE,FALSE,NULL);
 
+	// Start background thread that actually performs I/O
 	_injectSemaphore = CreateSemaphore(NULL,0,1,NULL);
 	_thread = Thread::start(this);
 }

vsprojects/TapDriver/dhcp.c

@@ -22,6 +22,8 @@
  *  59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */
 
+#if 0
+
 //=========================
 // Code to set DHCP options
 //=========================
@@ -597,3 +599,5 @@ DumpDHCP (const ETH_HEADER *eth,
 }
 
 #endif /* DBG */
+
+#endif

vsprojects/TapDriver/dhcp.h

@@ -22,6 +22,8 @@
  *  59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */
 
+#if 0
+
 #pragma pack(1)
 
 //===================================================
@@ -162,3 +164,5 @@ DumpDHCP (const ETH_HEADER *eth,
 	  const int optlen);
 
 #endif
+
+#endif

vsprojects/TapDriver/error.c

@@ -324,7 +324,8 @@ DumpPacket (const char *prefix,
 	       && blen - hlen >= (sizeof (UDPHDR)))
 	{
 	  const UDPHDR *udp = (UDPHDR *) (data + sizeof (ETH_HEADER) + hlen);
-	  
+
+#if 0
 	  // DHCP packet?
 	  if ((udp->dest == htons (BOOTPC_PORT) || udp->dest == htons (BOOTPS_PORT))
 	      && blen - hlen >= (sizeof (UDPHDR) + sizeof (DHCP)))
@@ -346,6 +347,7 @@ DumpPacket (const char *prefix,
 	      DumpDHCP (eth, ip, udp, dhcp, optlen);
 	      did = TRUE;
 	    }
+#endif
 
 	  if (!did)
 	    {

vsprojects/TapDriver/tap-windows.h

@@ -39,16 +39,16 @@
 #define TAP_WIN_IOCTL_GET_VERSION           TAP_WIN_CONTROL_CODE (2, METHOD_BUFFERED)
 #define TAP_WIN_IOCTL_GET_MTU               TAP_WIN_CONTROL_CODE (3, METHOD_BUFFERED)
 #define TAP_WIN_IOCTL_GET_INFO              TAP_WIN_CONTROL_CODE (4, METHOD_BUFFERED)
-#define TAP_WIN_IOCTL_CONFIG_POINT_TO_POINT TAP_WIN_CONTROL_CODE (5, METHOD_BUFFERED)
+//#define TAP_WIN_IOCTL_CONFIG_POINT_TO_POINT TAP_WIN_CONTROL_CODE (5, METHOD_BUFFERED)
 #define TAP_WIN_IOCTL_SET_MEDIA_STATUS      TAP_WIN_CONTROL_CODE (6, METHOD_BUFFERED)
-#define TAP_WIN_IOCTL_CONFIG_DHCP_MASQ      TAP_WIN_CONTROL_CODE (7, METHOD_BUFFERED)
+//#define TAP_WIN_IOCTL_CONFIG_DHCP_MASQ      TAP_WIN_CONTROL_CODE (7, METHOD_BUFFERED)
 #define TAP_WIN_IOCTL_GET_LOG_LINE          TAP_WIN_CONTROL_CODE (8, METHOD_BUFFERED)
-#define TAP_WIN_IOCTL_CONFIG_DHCP_SET_OPT   TAP_WIN_CONTROL_CODE (9, METHOD_BUFFERED)
+//#define TAP_WIN_IOCTL_CONFIG_DHCP_SET_OPT   TAP_WIN_CONTROL_CODE (9, METHOD_BUFFERED)
 
 /* Added in 8.2 */
 
 /* obsoletes TAP_WIN_IOCTL_CONFIG_POINT_TO_POINT */
-#define TAP_WIN_IOCTL_CONFIG_TUN            TAP_WIN_CONTROL_CODE (10, METHOD_BUFFERED)
+//#define TAP_WIN_IOCTL_CONFIG_TUN            TAP_WIN_CONTROL_CODE (10, METHOD_BUFFERED)
 
 /*
  * =================
@@ -57,7 +57,6 @@
  */
 
 #define ADAPTER_KEY "SYSTEM\\CurrentControlSet\\Control\\Class\\{4D36E972-E325-11CE-BFC1-08002BE10318}"
-
 #define NETWORK_CONNECTIONS_KEY "SYSTEM\\CurrentControlSet\\Control\\Network\\{4D36E972-E325-11CE-BFC1-08002BE10318}"
 
 /*

vsprojects/TapDriver/tapdrvr.c

@@ -62,7 +62,7 @@
 // Duplicates the functionality of OpenVPN's
 // --allow-nonadmin directive.
 //========================================================
-#define ENABLE_NONADMIN 1
+//#define ENABLE_NONADMIN 1
 
 #if defined(DDKVER_MAJOR) && DDKVER_MAJOR < 5600
 #include <ndis.h>
@@ -551,6 +551,7 @@ NDIS_STATUS AdapterCreate
 	   l_Adapter->m_MAC[0], l_Adapter->m_MAC[1], l_Adapter->m_MAC[2],
 	   l_Adapter->m_MAC[3], l_Adapter->m_MAC[4], l_Adapter->m_MAC[5]));
 
+#if 0
   //==================
   // Set broadcast MAC
   //==================
@@ -559,6 +560,7 @@ NDIS_STATUS AdapterCreate
     for (i = 0; i < sizeof (MACADDR); ++i)
       l_Adapter->m_MAC_Broadcast[i] = 0xFF;
   }
+#endif
 
   //====================================
   // Initialize TAP device
@@ -1480,6 +1482,7 @@ static IPV6ADDR IPV6_NS_TARGET_UNICAST =
 	{ 0xfe, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
           0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x08 };
 
+#if 0
 BOOLEAN
 HandleIPv6NeighborDiscovery( TapAdapterPointer p_Adapter, UCHAR * m_Data )
 {
@@ -1581,6 +1584,7 @@ HandleIPv6NeighborDiscovery( TapAdapterPointer p_Adapter, UCHAR * m_Data )
 
     return TRUE;				// all fine
 }
+#endif
 
 //====================================================================
 //                               Adapter Transmission
@@ -1662,6 +1666,7 @@ AdapterTransmit (IN NDIS_HANDLE p_AdapterContext,
     IPv4PacketSizeVerify (l_PacketBuffer->m_Data, l_PacketLength, FALSE, "TX", &l_Adapter->m_TxTrunc);
 #endif
 
+#if 0
     //=====================================================
     // Are we running in DHCP server masquerade mode?
     //
@@ -1687,7 +1692,9 @@ AdapterTransmit (IN NDIS_HANDLE p_AdapterContext,
 			    l_Adapter->m_dhcp_server_mac))
 	      goto no_queue;
 	  }
+#endif
 
+#if 0
 	// DHCP packet?
 	else if (l_PacketLength >= sizeof (ETH_HEADER) + sizeof (IPHDR) + sizeof (UDPHDR) + sizeof (DHCP)
 		 && eth->proto == htons (ETH_P_IP)
@@ -1715,6 +1722,7 @@ AdapterTransmit (IN NDIS_HANDLE p_AdapterContext,
 	      goto no_queue;
 	  }
       }
+#endif
 
     //===============================================
     // In Point-To-Point mode, check to see whether
@@ -1723,7 +1731,8 @@ AdapterTransmit (IN NDIS_HANDLE p_AdapterContext,
     // (to be handled locally), and the rest is forwarded
     // all other protocols are dropped
     //===============================================
-    if (l_Adapter->m_tun)
+#if 0
+	if (l_Adapter->m_tun)
       {
 	ETH_HEADER *e;
 
@@ -1790,8 +1799,9 @@ AdapterTransmit (IN NDIS_HANDLE p_AdapterContext,
 	    l_PacketBuffer->m_SizeFlags |= TP_TUN;
 	  }
       }
+#endif
 
-    //===============================================
+	//===============================================
     // Push packet onto queue to wait for read from
     // userspace.
     //===============================================
@@ -2051,6 +2061,7 @@ TapDeviceHook (IN PDEVICE_OBJECT p_DeviceObject, IN PIRP p_IRP)
 	    }
 #endif
 
+#if 0
 	  case TAP_WIN_IOCTL_CONFIG_TUN:
 	    {
 	      if (l_IrpSp->Parameters.DeviceIoControl.InputBufferLength >=
@@ -2097,7 +2108,9 @@ TapDeviceHook (IN PDEVICE_OBJECT p_DeviceObject, IN PIRP p_IRP)
 	      
 	      break;
 	    }
+#endif
 
+#if 0
 	  case TAP_WIN_IOCTL_CONFIG_POINT_TO_POINT: // Obsoleted by TAP_WIN_IOCTL_CONFIG_TUN
 	    {
 	      if (l_IrpSp->Parameters.DeviceIoControl.InputBufferLength >=
@@ -2136,6 +2149,7 @@ TapDeviceHook (IN PDEVICE_OBJECT p_DeviceObject, IN PIRP p_IRP)
 	      
 	      break;
 	    }
+#endif
 
 	  case TAP_WIN_IOCTL_SET_MEDIA_STATUS:
 	    {
@@ -2154,6 +2168,7 @@ TapDeviceHook (IN PDEVICE_OBJECT p_DeviceObject, IN PIRP p_IRP)
 	      break;
 	    }
 
+#if 0
 	  case TAP_WIN_IOCTL_CONFIG_DHCP_MASQ:
 	    {
 	      if (l_IrpSp->Parameters.DeviceIoControl.InputBufferLength >=
@@ -2220,6 +2235,7 @@ TapDeviceHook (IN PDEVICE_OBJECT p_DeviceObject, IN PIRP p_IRP)
 	      
 	      break;
 	    }
+#endif
 
 	  default:
 	    {
@@ -2370,6 +2386,7 @@ TapDeviceHook (IN PDEVICE_OBJECT p_DeviceObject, IN PIRP p_IRP)
 	    p_IRP->IoStatus.Status = l_Status = STATUS_UNSUCCESSFUL;
 	    p_IRP->IoStatus.Information = 0;
 	  }
+#if 0
 	else if (!l_Adapter->m_tun && ((l_IrpSp->Parameters.Write.Length) >= ETHERNET_HEADER_SIZE))
 	  {
 	    __try
@@ -2414,6 +2431,8 @@ TapDeviceHook (IN PDEVICE_OBJECT p_DeviceObject, IN PIRP p_IRP)
 		p_IRP->IoStatus.Information = 0;
 	      }
 	  }
+#endif
+#if 0
 	else if (l_Adapter->m_tun && ((l_IrpSp->Parameters.Write.Length) >= IP_HEADER_SIZE))
 	  {
 	    __try
@@ -2467,6 +2486,7 @@ TapDeviceHook (IN PDEVICE_OBJECT p_DeviceObject, IN PIRP p_IRP)
 		p_IRP->IoStatus.Information = 0;
 	      }
 	  }
+#endif
 	else
 	  {
 	    DEBUGP (("[%s] Bad buffer size in IRP_MJ_WRITE, len=%d\n",
@@ -2827,7 +2847,8 @@ SetMediaStatus (TapAdapterPointer p_Adapter, BOOLEAN state)
 VOID
 CheckIfDhcpAndTunMode (TapAdapterPointer p_Adapter)
 {
-  if (p_Adapter->m_tun && p_Adapter->m_dhcp_enabled)
+#if 0
+	if (p_Adapter->m_tun && p_Adapter->m_dhcp_enabled)
     {
       if ((p_Adapter->m_dhcp_server_ip & p_Adapter->m_remoteNetmask) == p_Adapter->m_remoteNetwork)
 	{
@@ -2835,8 +2856,10 @@ CheckIfDhcpAndTunMode (TapAdapterPointer p_Adapter)
 	  p_Adapter->m_dhcp_server_arp = FALSE;
 	}
     }
+#endif
 }
 
+#if 0
 //===================================================
 // Generate an ARP reply message for specific kinds
 // ARP queries.
@@ -2855,7 +2878,7 @@ ProcessARP (TapAdapterPointer p_Adapter,
   if (src->m_Proto == htons (ETH_P_ARP)
       && MAC_EQUAL (src->m_MAC_Source, p_Adapter->m_MAC)
       && MAC_EQUAL (src->m_ARP_MAC_Source, p_Adapter->m_MAC)
-      && MAC_EQUAL (src->m_MAC_Destination, p_Adapter->m_MAC_Broadcast)
+	  && MAC_EQUAL (src->m_MAC_Destination, p_Adapter->m_MAC_Broadcast)
       && src->m_ARP_Operation == htons (ARP_REQUEST)
       && src->m_MAC_AddressType == htons (MAC_ADDR_TYPE)
       && src->m_MAC_AddressSize == sizeof (MACADDR)
@@ -2902,6 +2925,7 @@ ProcessARP (TapAdapterPointer p_Adapter,
   else
     return FALSE;
 }
+#endif
 
 //===============================================================
 // Used in cases where internally generated packets such as
@@ -3003,6 +3027,7 @@ InjectPacketNow (TapAdapterPointer p_Adapter,
 //===================================================================
 VOID ResetTapAdapterState (TapAdapterPointer p_Adapter)
 {
+#if 0
   // Point-To-Point
   p_Adapter->m_tun = FALSE;
   p_Adapter->m_localIP = 0;
@@ -3023,6 +3048,7 @@ VOID ResetTapAdapterState (TapAdapterPointer p_Adapter)
   p_Adapter->m_dhcp_received_discover = FALSE;
   p_Adapter->m_dhcp_bad_requests = 0;
   NdisZeroMemory (p_Adapter->m_dhcp_server_mac, sizeof (MACADDR));
+#endif
 }
 
 #if ENABLE_NONADMIN

vsprojects/TapDriver/types.h

@@ -136,6 +136,7 @@ typedef struct _TapAdapter
   // Adapter power state
   char m_DeviceState;
 
+#if 0
   // Info for point-to-point mode
   BOOLEAN m_tun;
   IPADDR m_localIP;
@@ -145,7 +146,9 @@ typedef struct _TapAdapter
   ETH_HEADER m_UserToTap;
   ETH_HEADER m_UserToTap_IPv6;		// same as UserToTap but proto=ipv6
   MACADDR m_MAC_Broadcast;
+#endif
 
+#if 0
   // Used for DHCP server masquerade
   BOOLEAN m_dhcp_enabled;
   IPADDR m_dhcp_addr;
@@ -158,6 +161,7 @@ typedef struct _TapAdapter
   ULONG m_dhcp_user_supplied_options_buffer_len;
   BOOLEAN m_dhcp_received_discover;
   ULONG m_dhcp_bad_requests;
+#endif
 
   // Help to tear down the adapter by keeping
   // some state information on allocated