version 2.1_beta1

git-svn-id: http://svn.openvpn.net/projects/openvpn/branches/BETA21/openvpn@581 e7ae566f-a301-0410-adde-c780ea21d3b5

6 files changed, 376 insertions, 55 deletions

diff --git a/tap-win32/SOURCES b/tap-win32/SOURCES
index 5320ae3..f7c8dd6 100755
--- a/tap-win32/SOURCES
+++ b/tap-win32/SOURCES
@@ -15,7 +15,7 @@ INCLUDES=$(DDK_INCLUDE_PATH)
 # config-win32.h
 C_DEFINES=
 C_DEFINES=$(C_DEFINES) -DTAP_DRIVER_MAJOR_VERSION=8
-C_DEFINES=$(C_DEFINES) -DTAP_DRIVER_MINOR_VERSION=1
+C_DEFINES=$(C_DEFINES) -DTAP_DRIVER_MINOR_VERSION=307
 
 # Use 00:FF:XX:XX:XX:XX format MAC addresses where
 # the Xs are random (like Linux tap driver).
diff --git a/tap-win32/common.h b/tap-win32/common.h
index ef121b1..3c183c2 100755
--- a/tap-win32/common.h
+++ b/tap-win32/common.h
@@ -39,6 +39,8 @@
 #define TAP_CONTROL_CODE(request,method) \
   CTL_CODE (FILE_DEVICE_UNKNOWN, request, method, FILE_ANY_ACCESS)
 
+// Present in 8.1
+
 #define TAP_IOCTL_GET_MAC               TAP_CONTROL_CODE (1, METHOD_BUFFERED)
 #define TAP_IOCTL_GET_VERSION           TAP_CONTROL_CODE (2, METHOD_BUFFERED)
 #define TAP_IOCTL_GET_MTU               TAP_CONTROL_CODE (3, METHOD_BUFFERED)
@@ -49,6 +51,11 @@
 #define TAP_IOCTL_GET_LOG_LINE          TAP_CONTROL_CODE (8, METHOD_BUFFERED)
 #define TAP_IOCTL_CONFIG_DHCP_SET_OPT   TAP_CONTROL_CODE (9, METHOD_BUFFERED)
 
+// Added in 8.2
+
+/* obsoletes TAP_IOCTL_CONFIG_POINT_TO_POINT */
+#define TAP_IOCTL_CONFIG_TUN            TAP_CONTROL_CODE (10, METHOD_BUFFERED)
+
 //=================
 // Registry keys
 //=================
diff --git a/tap-win32/i386/OemWin2k.inf b/tap-win32/i386/OemWin2k.inf
index eb1e071..681c4b7 100755
--- a/tap-win32/i386/OemWin2k.inf
+++ b/tap-win32/i386/OemWin2k.inf
@@ -10,6 +10,11 @@
 ; chkinf c:\src\openvpn\tap-win32\i386\oemwin2k.inf
 ; OUTPUT -> file:///c:/WINDDK/3790/tools/chkinf/htm/c%23+src+openvpn+tap-win32+i386+__OemWin2k.htm
 
+; INSTALL/REMOVE DRIVER
+;   tapinstall install OemWin2k.inf TAP0801
+;   tapinstall update OemWin2k.inf TAP0801
+;   tapinstall remove TAP0801
+
 ;*********************************************************
 ; Note to Developers:
 ;
@@ -91,22 +96,28 @@
    HKR, ,               ProductName,  0, "%DeviceDescription%"
 
 [tap0801.params.reg]
-   HKR, Ndi\params\MTU,                ParamDesc, 0, "MTU"
-   HKR, Ndi\params\MTU,                Type,      0, "int"
-   HKR, Ndi\params\MTU,                Default,   0, "1500"
-   HKR, Ndi\params\MTU,                Optional,  0, "0"
-   HKR, Ndi\params\MTU,                Min,       0, "100"
-   HKR, Ndi\params\MTU,                Max,       0, "1500"
-   HKR, Ndi\params\MTU,                Step,      0, "1"
-   HKR, Ndi\params\MediaStatus,        ParamDesc, 0, "Media Status"
-   HKR, Ndi\params\MediaStatus,        Type,      0, "enum"
-   HKR, Ndi\params\MediaStatus,        Default,   0, "0"
-   HKR, Ndi\params\MediaStatus,        Optional,  0, "0"
-   HKR, Ndi\params\MediaStatus\enum,   "0",       0, "Application Controlled"
-   HKR, Ndi\params\MediaStatus\enum,   "1",       0, "Always Connected"
-   HKR, Ndi\params\MAC,                ParamDesc, 0, "MAC Address"
-   HKR, Ndi\params\MAC,                Type,      0, "edit"
-   HKR, Ndi\params\MAC,                Optional,  0, "1"
+   HKR, Ndi\params\MTU,                  ParamDesc, 0, "MTU"
+   HKR, Ndi\params\MTU,                  Type,      0, "int"
+   HKR, Ndi\params\MTU,                  Default,   0, "1500"
+   HKR, Ndi\params\MTU,                  Optional,  0, "0"
+   HKR, Ndi\params\MTU,                  Min,       0, "100"
+   HKR, Ndi\params\MTU,                  Max,       0, "1500"
+   HKR, Ndi\params\MTU,                  Step,      0, "1"
+   HKR, Ndi\params\MediaStatus,          ParamDesc, 0, "Media Status"
+   HKR, Ndi\params\MediaStatus,          Type,      0, "enum"
+   HKR, Ndi\params\MediaStatus,          Default,   0, "0"
+   HKR, Ndi\params\MediaStatus,          Optional,  0, "0"
+   HKR, Ndi\params\MediaStatus\enum,     "0",       0, "Application Controlled"
+   HKR, Ndi\params\MediaStatus\enum,     "1",       0, "Always Connected"
+   HKR, Ndi\params\MAC,                  ParamDesc, 0, "MAC Address"
+   HKR, Ndi\params\MAC,                  Type,      0, "edit"
+   HKR, Ndi\params\MAC,                  Optional,  0, "1"
+   HKR, Ndi\params\AllowNonAdmin,        ParamDesc, 0, "Non-Admin Access"
+   HKR, Ndi\params\AllowNonAdmin,        Type,      0, "enum"
+   HKR, Ndi\params\AllowNonAdmin,        Default,   0, "1"
+   HKR, Ndi\params\AllowNonAdmin,        Optional,  0, "0"
+   HKR, Ndi\params\AllowNonAdmin\enum,   "0",       0, "Not Allowed"
+   HKR, Ndi\params\AllowNonAdmin\enum,   "1",       0, "Allowed"
 
 ;----------------------------------------------------------------
 ;                             Service Section
diff --git a/tap-win32/prototypes.h b/tap-win32/prototypes.h
index 81f58f4..2237ed0 100755
--- a/tap-win32/prototypes.h
+++ b/tap-win32/prototypes.h
@@ -160,7 +160,8 @@ BOOLEAN ProcessARP
     TapAdapterPointer p_Adapter,
     const PARP_PACKET src,
     const IPADDR adapter_ip,
-    const IPADDR ip,
+    const IPADDR ip_network,
+    const IPADDR ip_netmask,
     const MACADDR mac
    );
 
@@ -177,11 +178,42 @@ VOID InjectPacket
     const unsigned int len
    );
 
-VOID CheckIfDhcpAndPointToPointMode
+VOID CheckIfDhcpAndTunMode
    (
     TapAdapterPointer p_Adapter
    );
 
 VOID HookDispatchFunctions();
 
+#if ENABLE_NONADMIN
+
+typedef struct _SECURITY_DESCRIPTOR {
+  unsigned char opaque[20];
+} SECURITY_DESCRIPTOR;
+
+NTSYSAPI
+NTSTATUS
+NTAPI
+ZwSetSecurityObject (
+  IN HANDLE  Handle,
+  IN SECURITY_INFORMATION  SecurityInformation,
+  IN PSECURITY_DESCRIPTOR  SecurityDescriptor);
+
+VOID AllowNonAdmin (TapExtensionPointer p_Extension);
+
+#endif
+
+#if PACKET_TRUNCATION_CHECK
+
+VOID IPv4PacketSizeVerify
+   (
+    const UCHAR *data,
+    ULONG length,
+    BOOLEAN tun,
+    const char *prefix,
+    LONG *counter
+   );
+
+#endif
+
 #endif
diff --git a/tap-win32/tapdrvr.c b/tap-win32/tapdrvr.c
index 7eecca7..0997bd5 100755
--- a/tap-win32/tapdrvr.c
+++ b/tap-win32/tapdrvr.c
@@ -35,7 +35,8 @@
 // By default we operate as a "tap" virtual ethernet
 // 802.3 interface, but we can emulate a "tun"
 // interface (point-to-point IPv4) through the
-// TAP_IOCTL_CONFIG_POINT_TO_POINT ioctl.
+// TAP_IOCTL_CONFIG_POINT_TO_POINT or
+// TAP_IOCTL_CONFIG_TUN ioctl.
 //======================================================
 
 #define NDIS_MINIPORT_DRIVER
@@ -46,11 +47,27 @@
 #define NTSTRSAFE_LIB
 
 // Debug info output
-#define ALSO_DBGPRINT      1
-#define DEBUGP_AT_DISPATCH 0
+#define ALSO_DBGPRINT           1
+#define DEBUGP_AT_DISPATCH      0
+
+//========================================================
+// Check for truncated IPv4 packets, log errors if found.
+//========================================================
+#define PACKET_TRUNCATION_CHECK 1 // JYFIXME
+
+//========================================================
+// EXPERIMENTAL -- Configure TAP device object to be
+// accessible from non-administrative accounts, based
+// on an advanced properties setting.
+//
+// Duplicates the functionality of OpenVPN's
+// --allow-nonadmin directive.
+//========================================================
+#define ENABLE_NONADMIN 1         // JYFIXME
 
 #include <ndis.h>
 #include <ntstrsafe.h>
+#include <ntddk.h>
 
 #include "lock.h"
 #include "constants.h"
@@ -274,6 +291,10 @@ NDIS_STATUS AdapterCreate
   UINT l_Index;
   NDIS_STATUS status;
 
+#if ENABLE_NONADMIN
+  BOOLEAN enable_non_admin = FALSE;
+#endif
+
   //====================================
   // Make sure adapter type is supported
   //====================================
@@ -410,6 +431,25 @@ NDIS_STATUS AdapterCreate
 	    }
 	}
 
+#if ENABLE_NONADMIN
+	/* Read AllowNonAdmin setting from registry */
+	{
+	  NDIS_STRING key = NDIS_STRING_CONST("AllowNonAdmin");
+	  NdisReadConfiguration (&status, &parm, configHandle,
+				 &key, NdisParameterInteger);
+	  if (status == NDIS_STATUS_SUCCESS)
+	    {
+	      if (parm->ParameterType == NdisParameterInteger)
+		{
+		  if (parm->ParameterData.IntegerData)
+		    {
+			enable_non_admin = TRUE;
+		    }
+		}
+	    }
+	}
+#endif
+
 	/* Read optional MAC setting from registry */
 	{
 	  NDIS_STRING key = NDIS_STRING_CONST("MAC");
@@ -479,6 +519,11 @@ NDIS_STATUS AdapterCreate
 
   l_Adapter->m_InterfaceIsRunning = TRUE;
 
+#if ENABLE_NONADMIN
+  if (enable_non_admin)
+    AllowNonAdmin (&l_Adapter->m_Extension);
+#endif
+
   return NDIS_STATUS_SUCCESS;
 }
 
@@ -1011,7 +1056,7 @@ NDIS_STATUS AdapterQuery
       break;
       
     case OID_GEN_LINK_SPEED:
-      l_Query.m_Long = 100000;
+      l_Query.m_Long = 100000; // rate / 100 bps
       break;
 
     case OID_802_3_PERMANENT_ADDRESS:
@@ -1348,19 +1393,40 @@ AdapterTransmit (IN NDIS_HANDLE p_AdapterContext,
 
   __try
   {
-    for (l_Index = 0; l_NDIS_Buffer && l_Index < l_PacketLength;
-	 l_Index += l_BufferLength)
+    l_Index = 0;
+    while (l_NDIS_Buffer && l_Index < l_PacketLength)
       {
+	ULONG newlen;
 	NdisQueryBuffer (l_NDIS_Buffer, (PVOID *) & l_Buffer,
 			 &l_BufferLength);
+	newlen = l_Index + l_BufferLength;
+	if (newlen > l_PacketLength)
+	  {
+	    NOTE_ERROR ();
+	    goto no_queue; /* overflow */
+	  }
 	NdisMoveMemory (l_PacketBuffer->m_Data + l_Index, l_Buffer,
 			l_BufferLength);
+	l_Index = newlen;
 	NdisGetNextBuffer (l_NDIS_Buffer, &l_NDIS_Buffer);
       }
+    if (l_Index != l_PacketLength)
+      {
+	NOTE_ERROR ();
+	goto no_queue; /* underflow */
+      }
 
     DUMP_PACKET ("AdapterTransmit", l_PacketBuffer->m_Data, l_PacketLength);
 
     //=====================================================
+    // If IPv4 packet, check whether or not packet
+    // was truncated.
+    //=====================================================
+#if PACKET_TRUNCATION_CHECK
+    IPv4PacketSizeVerify (l_PacketBuffer->m_Data, l_PacketLength, FALSE, "TX", &l_Adapter->m_TxTrunc);
+#endif
+
+    //=====================================================
     // Are we running in DHCP server masquerade mode?
     //
     // If so, catch both DHCP requests and ARP queries
@@ -1381,6 +1447,7 @@ AdapterTransmit (IN NDIS_HANDLE p_AdapterContext,
 			    (PARP_PACKET) l_PacketBuffer->m_Data,
 			    l_Adapter->m_dhcp_addr,
 			    l_Adapter->m_dhcp_server_ip,
+			    ~0,
 			    l_Adapter->m_dhcp_server_mac))
 	      goto no_queue;
 	  }
@@ -1417,7 +1484,7 @@ AdapterTransmit (IN NDIS_HANDLE p_AdapterContext,
     // In Point-To-Point mode, check to see whether
     // packet is ARP or IPv4 (if neither, then drop).
     //===============================================
-    if (l_Adapter->m_PointToPoint)
+    if (l_Adapter->m_tun)
       {
 	ETH_HEADER *e;
 
@@ -1438,7 +1505,8 @@ AdapterTransmit (IN NDIS_HANDLE p_AdapterContext,
 	    ProcessARP (l_Adapter,
 			(PARP_PACKET) l_PacketBuffer->m_Data,
 			l_Adapter->m_localIP,
-			l_Adapter->m_remoteIP,
+			l_Adapter->m_remoteNetwork,
+			l_Adapter->m_remoteNetmask,
 			l_Adapter->m_TapToUser.dest);
 
 	  default:
@@ -1458,7 +1526,7 @@ AdapterTransmit (IN NDIS_HANDLE p_AdapterContext,
 	      goto no_queue;
 
 	    // Packet looks like IPv4, queue it.
-	    l_PacketBuffer->m_SizeFlags |= TP_POINT_TO_POINT;
+	    l_PacketBuffer->m_SizeFlags |= TP_TUN;
 	  }
       }
 
@@ -1669,15 +1737,25 @@ TapDeviceHook (IN PDEVICE_OBJECT p_DeviceObject, IN PIRP p_IRP)
 		NULL,
 		NULL,
 		STRSAFE_FILL_BEHIND_NULL | STRSAFE_IGNORE_NULLS,
+#if PACKET_TRUNCATION_CHECK
+		"State=%s Err=[%s/%d] #O=%d Tx=[%d,%d,%d] Rx=[%d,%d,%d] IrpQ=[%d,%d,%d] PktQ=[%d,%d,%d]",
+#else
 		"State=%s Err=[%s/%d] #O=%d Tx=[%d,%d] Rx=[%d,%d] IrpQ=[%d,%d,%d] PktQ=[%d,%d,%d]",
+#endif
 		state,
 		g_LastErrorFilename,
 		g_LastErrorLineNumber,
 		(int)l_Adapter->m_Extension.m_NumTapOpens,
 		(int)l_Adapter->m_Tx,
 		(int)l_Adapter->m_TxErr,
+#if PACKET_TRUNCATION_CHECK
+		(int)l_Adapter->m_TxTrunc,
+#endif
 		(int)l_Adapter->m_Rx,
 		(int)l_Adapter->m_RxErr,
+#if PACKET_TRUNCATION_CHECK
+		(int)l_Adapter->m_RxTrunc,
+#endif
 		(int)l_Adapter->m_Extension.m_IrpQueue->size,
 		(int)l_Adapter->m_Extension.m_IrpQueue->max_size,
 		(int)IRP_QUEUE_SIZE,
@@ -1708,21 +1786,65 @@ TapDeviceHook (IN PDEVICE_OBJECT p_DeviceObject, IN PIRP p_IRP)
 	    }
 #endif
 
-	  case TAP_IOCTL_CONFIG_POINT_TO_POINT:
+	  case TAP_IOCTL_CONFIG_TUN:
+	    {
+	      if (l_IrpSp->Parameters.DeviceIoControl.InputBufferLength >=
+		  (sizeof (IPADDR) * 3))
+		{
+		  MACADDR dest;
+
+		  l_Adapter->m_tun = FALSE;
+
+		  GenerateRelatedMAC (dest, l_Adapter->m_MAC, 1);
+
+		  l_Adapter->m_localIP =       ((IPADDR*) (p_IRP->AssociatedIrp.SystemBuffer))[0];
+		  l_Adapter->m_remoteNetwork = ((IPADDR*) (p_IRP->AssociatedIrp.SystemBuffer))[1];
+		  l_Adapter->m_remoteNetmask = ((IPADDR*) (p_IRP->AssociatedIrp.SystemBuffer))[2];
+
+		  // sanity check on network/netmask
+		  if ((l_Adapter->m_remoteNetwork & l_Adapter->m_remoteNetmask) != l_Adapter->m_remoteNetwork)
+		    {
+		      NOTE_ERROR ();
+		      p_IRP->IoStatus.Status = l_Status = STATUS_INVALID_PARAMETER;
+		      break;
+		    }
+
+		  COPY_MAC (l_Adapter->m_TapToUser.src, l_Adapter->m_MAC);
+		  COPY_MAC (l_Adapter->m_TapToUser.dest, dest);
+		  COPY_MAC (l_Adapter->m_UserToTap.src, dest);
+		  COPY_MAC (l_Adapter->m_UserToTap.dest, l_Adapter->m_MAC);
+
+		  l_Adapter->m_TapToUser.proto = l_Adapter->m_UserToTap.proto = htons (ETH_P_IP);
+
+		  l_Adapter->m_tun = TRUE;
+
+		  CheckIfDhcpAndTunMode (l_Adapter);
+
+		  p_IRP->IoStatus.Information = 1; // Simple boolean value
+		}
+	      else
+		{
+		  NOTE_ERROR ();
+		  p_IRP->IoStatus.Status = l_Status = STATUS_INVALID_PARAMETER;
+		}
+	      
+	      break;
+	    }
+
+	  case TAP_IOCTL_CONFIG_POINT_TO_POINT: // Obsoleted by TAP_IOCTL_CONFIG_TUN
 	    {
 	      if (l_IrpSp->Parameters.DeviceIoControl.InputBufferLength >=
 		  (sizeof (IPADDR) * 2))
 		{
 		  MACADDR dest;
 
-		  l_Adapter->m_PointToPoint = FALSE;
+		  l_Adapter->m_tun = FALSE;
 
 		  GenerateRelatedMAC (dest, l_Adapter->m_MAC, 1);
 
-		  l_Adapter->m_localIP =
-		    ((IPADDR*) (p_IRP->AssociatedIrp.SystemBuffer))[0];
-		  l_Adapter->m_remoteIP =
-		    ((IPADDR*) (p_IRP->AssociatedIrp.SystemBuffer))[1];
+		  l_Adapter->m_localIP =       ((IPADDR*) (p_IRP->AssociatedIrp.SystemBuffer))[0];
+		  l_Adapter->m_remoteNetwork = ((IPADDR*) (p_IRP->AssociatedIrp.SystemBuffer))[1];
+		  l_Adapter->m_remoteNetmask = ~0;
 
 		  COPY_MAC (l_Adapter->m_TapToUser.src, l_Adapter->m_MAC);
 		  COPY_MAC (l_Adapter->m_TapToUser.dest, dest);
@@ -1731,9 +1853,9 @@ TapDeviceHook (IN PDEVICE_OBJECT p_DeviceObject, IN PIRP p_IRP)
 
 		  l_Adapter->m_TapToUser.proto = l_Adapter->m_UserToTap.proto = htons (ETH_P_IP);
 
-		  l_Adapter->m_PointToPoint = TRUE;
+		  l_Adapter->m_tun = TRUE;
 
-		  CheckIfDhcpAndPointToPointMode (l_Adapter);
+		  CheckIfDhcpAndTunMode (l_Adapter);
 
 		  p_IRP->IoStatus.Information = 1; // Simple boolean value
 		}
@@ -1791,7 +1913,7 @@ TapDeviceHook (IN PDEVICE_OBJECT p_DeviceObject, IN PIRP p_IRP)
 		  l_Adapter->m_dhcp_enabled = TRUE;
 		  l_Adapter->m_dhcp_server_arp = TRUE;
 
-		  CheckIfDhcpAndPointToPointMode (l_Adapter);
+		  CheckIfDhcpAndTunMode (l_Adapter);
 
 		  p_IRP->IoStatus.Information = 1; // Simple boolean value
 		}
@@ -1979,7 +2101,7 @@ TapDeviceHook (IN PDEVICE_OBJECT p_DeviceObject, IN PIRP p_IRP)
 	    p_IRP->IoStatus.Status = l_Status = STATUS_UNSUCCESSFUL;
 	    p_IRP->IoStatus.Information = 0;
 	  }
-	else if (!l_Adapter->m_PointToPoint && ((l_IrpSp->Parameters.Write.Length) >= ETHERNET_HEADER_SIZE))
+	else if (!l_Adapter->m_tun && ((l_IrpSp->Parameters.Write.Length) >= ETHERNET_HEADER_SIZE))
 	  {
 	    __try
 	      {
@@ -1989,6 +2111,18 @@ TapDeviceHook (IN PDEVICE_OBJECT p_DeviceObject, IN PIRP p_IRP)
 			     (unsigned char *) p_IRP->AssociatedIrp.SystemBuffer,
 			     l_IrpSp->Parameters.Write.Length);
 
+    //=====================================================
+    // If IPv4 packet, check whether or not packet
+    // was truncated.
+    //=====================================================
+#if PACKET_TRUNCATION_CHECK
+		IPv4PacketSizeVerify ((unsigned char *) p_IRP->AssociatedIrp.SystemBuffer,
+				      l_IrpSp->Parameters.Write.Length,
+				      FALSE,
+				      "RX",
+				      &l_Adapter->m_RxTrunc);
+#endif
+
 		NdisMEthIndicateReceive
 		  (l_Adapter->m_MiniportAdapterHandle,
 		   (NDIS_HANDLE) l_Adapter,
@@ -2011,7 +2145,7 @@ TapDeviceHook (IN PDEVICE_OBJECT p_DeviceObject, IN PIRP p_IRP)
 		p_IRP->IoStatus.Information = 0;
 	      }
 	  }
-	else if (l_Adapter->m_PointToPoint && ((l_IrpSp->Parameters.Write.Length) >= IP_HEADER_SIZE))
+	else if (l_Adapter->m_tun && ((l_IrpSp->Parameters.Write.Length) >= IP_HEADER_SIZE))
 	  {
 	    __try
 	      {
@@ -2022,6 +2156,18 @@ TapDeviceHook (IN PDEVICE_OBJECT p_DeviceObject, IN PIRP p_IRP)
 			      (unsigned char *) p_IRP->AssociatedIrp.SystemBuffer,
 			      l_IrpSp->Parameters.Write.Length);
 
+    //=====================================================
+    // If IPv4 packet, check whether or not packet
+    // was truncated.
+    //=====================================================
+#if PACKET_TRUNCATION_CHECK
+		IPv4PacketSizeVerify ((unsigned char *) p_IRP->AssociatedIrp.SystemBuffer,
+				      l_IrpSp->Parameters.Write.Length,
+				      TRUE,
+				      "RX",
+				      &l_Adapter->m_RxTrunc);
+#endif
+
 		NdisMEthIndicateReceive
 		  (l_Adapter->m_MiniportAdapterHandle,
 		   (NDIS_HANDLE) l_Adapter,
@@ -2197,7 +2343,7 @@ CompleteIRP (IN PIRP p_IRP,
   // component.
   //-------------------------------------------
 
-  if (p_PacketBuffer->m_SizeFlags & TP_POINT_TO_POINT)
+  if (p_PacketBuffer->m_SizeFlags & TP_TUN)
     {
       offset = ETHERNET_HEADER_SIZE;
       len = (int) (p_PacketBuffer->m_SizeFlags & TP_SIZE_MASK) - ETHERNET_HEADER_SIZE;
@@ -2379,16 +2525,16 @@ SetMediaStatus (TapAdapterPointer p_Adapter, BOOLEAN state)
 
 
 //======================================================
-// If DHCP mode is used together with Point-to-point
-// mode, consider the fact that the P2P remote endpoint
-// might be equal to the DHCP masq server address.
+// If DHCP mode is used together with tun
+// mode, consider the fact that the P2P remote subnet
+// might enclose the DHCP masq server address.
 //======================================================
 VOID
-CheckIfDhcpAndPointToPointMode (TapAdapterPointer p_Adapter)
+CheckIfDhcpAndTunMode (TapAdapterPointer p_Adapter)
 {
-  if (p_Adapter->m_PointToPoint && p_Adapter->m_dhcp_enabled)
+  if (p_Adapter->m_tun && p_Adapter->m_dhcp_enabled)
     {
-      if (p_Adapter->m_dhcp_server_ip == p_Adapter->m_remoteIP)
+      if ((p_Adapter->m_dhcp_server_ip & p_Adapter->m_remoteNetmask) == p_Adapter->m_remoteNetwork)
 	{
 	  COPY_MAC (p_Adapter->m_dhcp_server_mac, p_Adapter->m_TapToUser.dest);
 	  p_Adapter->m_dhcp_server_arp = FALSE;
@@ -2404,7 +2550,8 @@ BOOLEAN
 ProcessARP (TapAdapterPointer p_Adapter,
 	    const PARP_PACKET src,
 	    const IPADDR adapter_ip,
-	    const IPADDR ip,
+	    const IPADDR ip_network,
+	    const IPADDR ip_netmask,
 	    const MACADDR mac)
 {
   //-----------------------------------------------
@@ -2420,7 +2567,8 @@ ProcessARP (TapAdapterPointer p_Adapter,
       && src->m_PROTO_AddressType == htons (ETH_P_IP)
       && src->m_PROTO_AddressSize == sizeof (IPADDR)
       && src->m_ARP_IP_Source == adapter_ip
-      && src->m_ARP_IP_Destination == ip)
+      && (src->m_ARP_IP_Destination & ip_netmask) == ip_network
+      && src->m_ARP_IP_Destination != adapter_ip)
     {
       ARP_PACKET *arp = (ARP_PACKET *) MemAlloc (sizeof (ARP_PACKET), TRUE);
       if (arp)
@@ -2442,7 +2590,7 @@ ProcessARP (TapAdapterPointer p_Adapter,
 	  COPY_MAC (arp->m_MAC_Destination, p_Adapter->m_MAC);
 	  COPY_MAC (arp->m_ARP_MAC_Source, mac);
 	  COPY_MAC (arp->m_ARP_MAC_Destination, p_Adapter->m_MAC);
-	  arp->m_ARP_IP_Source = ip;
+	  arp->m_ARP_IP_Source = src->m_ARP_IP_Destination;
 	  arp->m_ARP_IP_Destination = adapter_ip;
 
 	  DUMP_PACKET ("ProcessARP",
@@ -2508,9 +2656,10 @@ InjectPacket (TapAdapterPointer p_Adapter,
 VOID ResetTapAdapterState (TapAdapterPointer p_Adapter)
 {
   // Point-To-Point
-  p_Adapter->m_PointToPoint = FALSE;
+  p_Adapter->m_tun = FALSE;
   p_Adapter->m_localIP = 0;
-  p_Adapter->m_remoteIP = 0;
+  p_Adapter->m_remoteNetwork = 0;
+  p_Adapter->m_remoteNetmask = 0;
   NdisZeroMemory (&p_Adapter->m_TapToUser, sizeof (p_Adapter->m_TapToUser));
   NdisZeroMemory (&p_Adapter->m_UserToTap, sizeof (p_Adapter->m_UserToTap));
 
@@ -2526,6 +2675,124 @@ VOID ResetTapAdapterState (TapAdapterPointer p_Adapter)
   p_Adapter->m_dhcp_bad_requests = 0;
   NdisZeroMemory (p_Adapter->m_dhcp_server_mac, sizeof (MACADDR));
 }
+
+#if ENABLE_NONADMIN
+
+//===================================================================
+// Set TAP device handle to be accessible without admin privileges.
+//===================================================================
+VOID AllowNonAdmin (TapExtensionPointer p_Extension)
+{
+  NTSTATUS stat;
+  SECURITY_DESCRIPTOR sd;
+  OBJECT_ATTRIBUTES oa;
+  IO_STATUS_BLOCK isb;
+  HANDLE hand = NULL;
+
+  NdisZeroMemory (&sd, sizeof (sd));
+  NdisZeroMemory (&oa, sizeof (oa));
+  NdisZeroMemory (&isb, sizeof (isb));
+
+  if (!p_Extension->m_CreatedUnicodeLinkName)
+    {
+      DEBUGP (("[TAP] AllowNonAdmin: UnicodeLinkName is uninitialized\n"));
+      NOTE_ERROR ();
+      return;
+    }
+
+  stat = RtlCreateSecurityDescriptor (&sd, SECURITY_DESCRIPTOR_REVISION);
+  if (stat != STATUS_SUCCESS)
+    {
+      DEBUGP (("[TAP] AllowNonAdmin: RtlCreateSecurityDescriptor failed\n"));
+      NOTE_ERROR ();
+      return;
+    }
+
+  InitializeObjectAttributes (
+    &oa,
+    &p_Extension->m_UnicodeLinkName,
+    OBJ_KERNEL_HANDLE,
+    NULL,
+    NULL
+    );
+
+  stat = ZwOpenFile (
+    &hand,
+    WRITE_DAC,
+    &oa,
+    &isb,
+    0,
+    0
+    );
+  if (stat != STATUS_SUCCESS)
+    {
+      DEBUGP (("[TAP] AllowNonAdmin: ZwOpenFile failed, status=0x%08x\n", (unsigned int)stat));
+      NOTE_ERROR ();
+      return;
+    }
+
+  stat = ZwSetSecurityObject (hand, DACL_SECURITY_INFORMATION, &sd);
+  if (stat != STATUS_SUCCESS)
+    {
+      DEBUGP (("[TAP] AllowNonAdmin: ZwSetSecurityObject failed\n"));
+      NOTE_ERROR ();
+      return;
+    }
+
+  stat = ZwClose (hand);
+  if (stat != STATUS_SUCCESS)
+    {
+      DEBUGP (("[TAP] AllowNonAdmin: ZwClose failed\n"));
+      NOTE_ERROR ();
+      return;
+    }
+
+  DEBUGP (("[TAP] AllowNonAdmin: SUCCEEDED\n"));
+}
+
+#endif
+
+#if PACKET_TRUNCATION_CHECK
+
+VOID
+IPv4PacketSizeVerify (const UCHAR *data, ULONG length, BOOLEAN tun, const char *prefix, LONG *counter)
+{
+  const IPHDR *ip;
+  int len = length;
+
+  if (tun)
+    {
+      ip = (IPHDR *) data;
+    }
+  else
+    {
+      if (length >= sizeof (ETH_HEADER))
+	{
+	  const ETH_HEADER *eth = (ETH_HEADER *) data;
+
+	  if (eth->proto != htons (ETH_P_IP))
+	    return;
+
+	  ip = (IPHDR *) (data + sizeof (ETH_HEADER));
+	  len -= sizeof (ETH_HEADER);
+	}
+      else
+	return;
+    }
+
+  if (len >= sizeof (IPHDR))
+    {
+      const int totlen = ntohs (ip->tot_len);
+
+      DEBUGP (("[TAP] IPv4PacketSizeVerify %s len=%d totlen=%d\n", prefix, len, totlen));
+
+      if (len != totlen)
+	++(*counter);
+    }
+}
+
+#endif
+
 //======================================================================
 //                                    End of Source
 //======================================================================
diff --git a/tap-win32/types.h b/tap-win32/types.h
index f5a4291..45e0033 100755
--- a/tap-win32/types.h
+++ b/tap-win32/types.h
@@ -92,8 +92,8 @@ TapExtension, *TapExtensionPointer;
 typedef struct _TapPacket
    {
 #   define TAP_PACKET_SIZE(data_size) (sizeof (TapPacket) + (data_size))
-#   define TP_POINT_TO_POINT 0x80000000
-#   define TP_SIZE_MASK      (~TP_POINT_TO_POINT)
+#   define TP_TUN 0x80000000
+#   define TP_SIZE_MASK      (~TP_TUN)
     ULONG m_SizeFlags;
     UCHAR m_Data []; // m_Data must be the last struct member
    }
@@ -107,6 +107,9 @@ typedef struct _TapAdapter
   BOOLEAN m_InterfaceIsRunning;
   NDIS_HANDLE m_MiniportAdapterHandle;
   LONG m_Rx, m_Tx, m_RxErr, m_TxErr;
+#if PACKET_TRUNCATION_CHECK
+  LONG m_RxTrunc, m_TxTrunc;
+#endif
   NDIS_MEDIUM m_Medium;
   ULONG m_Lookahead;
   ULONG m_MTU;
@@ -123,9 +126,10 @@ typedef struct _TapAdapter
   char m_DeviceState;
 
   // Info for point-to-point mode
-  BOOLEAN m_PointToPoint;
+  BOOLEAN m_tun;
   IPADDR m_localIP;
-  IPADDR m_remoteIP;
+  IPADDR m_remoteNetwork;
+  IPADDR m_remoteNetmask;
   ETH_HEADER m_TapToUser;
   ETH_HEADER m_UserToTap;
   MACADDR m_MAC_Broadcast;