tapdrvr.c

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/*
 *  TAP-Win32 -- A kernel driver to provide virtual tap device
 *               functionality on Windows.  Originally derived
 *               from the CIPE-Win32 project by Damion K. Wilson,
 *               with extensive modifications by James Yonan.
 *
 *  All source code which derives from the CIPE-Win32 project is
 *  Copyright (C) Damion K. Wilson, 2003, and is released under the
 *  GPL version 2 (see below).
 *
 *  All other source code is Copyright (C) James Yonan, 2003-2004,
 *  and is released under the GPL version 2 (see below).
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program (see the file COPYING included with this
 *  distribution); if not, write to the Free Software Foundation, Inc.,
 *  59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

//======================================================
// This driver is designed to work on Win 2000 or higher
// versions of Windows.
//
// It is SMP-safe and handles NDIS 5 power management.
//
// 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.
//======================================================

#define NDIS_MINIPORT_DRIVER
#define BINARY_COMPATIBLE 0
#define NDIS50_MINIPORT 1
#define NDIS_WDM 0
#define NDIS50 1
#define NTSTRSAFE_LIB

// Debug info output
#define ALSO_DBGPRINT      1
#define DEBUGP_AT_DISPATCH 0

#include <ndis.h>
#include <ntstrsafe.h>

#include "lock.h"
#include "constants.h"
#include "common.h"
#include "proto.h"
#include "error.h"
#include "endian.h"
#include "dhcp.h"
#include "types.h"
#include "prototypes.h"

#include "mem.c"
#include "macinfo.c"
#include "error.c"
#include "dhcp.c"
#include "instance.c"

#define IS_UP(ta) \
  ((ta)->m_InterfaceIsRunning && (ta)->m_Extension.m_TapIsRunning)

#define INCREMENT_STAT(s) ++(s)

#define NAME_BUFFER_SIZE 80

//========================================================
//                            Globals
//========================================================

NDIS_HANDLE g_NdisWrapperHandle;

const UINT g_SupportedOIDList[] = {
  OID_GEN_HARDWARE_STATUS,
  OID_GEN_MEDIA_SUPPORTED,
  OID_GEN_MEDIA_IN_USE,
  OID_GEN_MAXIMUM_LOOKAHEAD,
  OID_GEN_MAC_OPTIONS,
  OID_GEN_LINK_SPEED,
  OID_GEN_TRANSMIT_BLOCK_SIZE,
  OID_GEN_RECEIVE_BLOCK_SIZE,
  OID_GEN_VENDOR_DESCRIPTION,
  OID_GEN_DRIVER_VERSION,
  OID_GEN_XMIT_OK,
  OID_GEN_RCV_OK,
  OID_GEN_XMIT_ERROR,
  OID_GEN_RCV_ERROR,
  OID_802_3_PERMANENT_ADDRESS,
  OID_802_3_CURRENT_ADDRESS,
  OID_GEN_RCV_NO_BUFFER,
  OID_802_3_RCV_ERROR_ALIGNMENT,
  OID_802_3_XMIT_ONE_COLLISION,
  OID_802_3_XMIT_MORE_COLLISIONS,
  OID_802_3_MULTICAST_LIST,
  OID_802_3_MAXIMUM_LIST_SIZE,
  OID_GEN_VENDOR_ID,
  OID_GEN_CURRENT_LOOKAHEAD,
  OID_GEN_CURRENT_PACKET_FILTER,
  OID_GEN_PROTOCOL_OPTIONS,
  OID_GEN_MAXIMUM_TOTAL_SIZE,
  OID_GEN_TRANSMIT_BUFFER_SPACE,
  OID_GEN_RECEIVE_BUFFER_SPACE,
  OID_GEN_MAXIMUM_FRAME_SIZE,
  OID_GEN_VENDOR_DRIVER_VERSION,
  OID_GEN_MAXIMUM_SEND_PACKETS,
  OID_GEN_MEDIA_CONNECT_STATUS,
  OID_GEN_SUPPORTED_LIST
};

//============================================================
//                         Driver Entry
//============================================================
#pragma NDIS_INIT_FUNCTION (DriverEntry)

NTSTATUS
DriverEntry (IN PDRIVER_OBJECT p_DriverObject,
	     IN PUNICODE_STRING p_RegistryPath)
{
  NDIS_STATUS l_Status = NDIS_STATUS_FAILURE;
  NDIS_MINIPORT_CHARACTERISTICS *l_Properties = NULL;

  //========================================================
  // Notify NDIS that a new miniport driver is initializing.
  //========================================================

  NdisMInitializeWrapper (&g_NdisWrapperHandle,
			  p_DriverObject,
			  p_RegistryPath, NULL);

  //======================
  // Global initialization
  //======================

#if DBG
  MyDebugInit (10000); // Allocate debugging text space
#endif

  if (!InitInstanceList ())
    {
      DEBUGP (("[TAP] Allocation failed for adapter instance list\n"));
      goto cleanup;
    }

  //=======================================
  // Set and register miniport entry points
  //=======================================

  l_Properties = MemAlloc (sizeof (NDIS_MINIPORT_CHARACTERISTICS), TRUE);

  if (l_Properties == NULL)
    {
      DEBUGP (("[TAP] Allocation failed for miniport entry points\n"));
      goto cleanup;
    }

  l_Properties->MajorNdisVersion = TAP_NDIS_MAJOR_VERSION;
  l_Properties->MinorNdisVersion = TAP_NDIS_MINOR_VERSION;
  l_Properties->InitializeHandler = AdapterCreate;
  l_Properties->HaltHandler = AdapterHalt;
  l_Properties->ResetHandler = AdapterReset;               /* DISPATCH_LEVEL */
  l_Properties->TransferDataHandler = AdapterReceive;      /* DISPATCH_LEVEL */
  l_Properties->SendHandler = AdapterTransmit;             /* DISPATCH_LEVEL */
  l_Properties->QueryInformationHandler = AdapterQuery;    /* DISPATCH_LEVEL */
  l_Properties->SetInformationHandler = AdapterModify;     /* DISPATCH_LEVEL */

  switch (l_Status =
	  NdisMRegisterMiniport (g_NdisWrapperHandle, l_Properties,
				 sizeof (NDIS_MINIPORT_CHARACTERISTICS)))
    {
    case NDIS_STATUS_SUCCESS:
      {
	DEBUGP (("[TAP] version [%d.%d] %s %s registered miniport successfully\n",
		 TAP_DRIVER_MAJOR_VERSION,
		 TAP_DRIVER_MINOR_VERSION,
		 __DATE__,
		 __TIME__));
	DEBUGP (("Registry Path: '%S'\n", p_RegistryPath->Buffer));
	break;
      }

    case NDIS_STATUS_BAD_CHARACTERISTICS:
      {
	DEBUGP (("[TAP] Miniport characteristics were badly defined\n"));
	NdisTerminateWrapper (g_NdisWrapperHandle, NULL);
	break;
      }

    case NDIS_STATUS_BAD_VERSION:
      {
	DEBUGP
	  (("[TAP] NDIS Version is wrong for the given characteristics\n"));
	NdisTerminateWrapper (g_NdisWrapperHandle, NULL);
	break;
      }

    case NDIS_STATUS_RESOURCES:
      {
	DEBUGP (("[TAP] Insufficient resources\n"));
	NdisTerminateWrapper (g_NdisWrapperHandle, NULL);
	break;
      }

    default:
    case NDIS_STATUS_FAILURE:
      {
	DEBUGP (("[TAP] Unknown fatal registration error\n"));
	NdisTerminateWrapper (g_NdisWrapperHandle, NULL);
	break;
      }
    }

 cleanup:
  if (l_Properties)
    MemFree (l_Properties, sizeof (NDIS_MINIPORT_CHARACTERISTICS));

  if (l_Status == NDIS_STATUS_SUCCESS)
    NdisMRegisterUnloadHandler (g_NdisWrapperHandle, TapDriverUnload);
  else
    TapDriverUnload (p_DriverObject);

  return l_Status;
}

//============================================================
//                         Driver Unload
//============================================================
VOID 
TapDriverUnload (IN PDRIVER_OBJECT p_DriverObject)
{
  DEBUGP (("[TAP] version [%d.%d] %s %s unloaded, instances=%d, imbs=%d\n",
	   TAP_DRIVER_MAJOR_VERSION,
	   TAP_DRIVER_MINOR_VERSION,
	   __DATE__,
	   __TIME__,
	   NInstances(),
	   InstanceMaxBucketSize()));

  FreeInstanceList ();

  //==============================
  // Free debugging text space
  //==============================
#if DBG
  MyDebugFree ();
#endif
}

//==========================================================
//                            Adapter Initialization
//==========================================================
NDIS_STATUS AdapterCreate
  (OUT PNDIS_STATUS p_ErrorStatus,
   OUT PUINT p_MediaIndex,
   IN PNDIS_MEDIUM p_Media,
   IN UINT p_MediaCount,
   IN NDIS_HANDLE p_AdapterHandle,
   IN NDIS_HANDLE p_ConfigurationHandle)
{
  TapAdapterPointer l_Adapter = NULL;

  NDIS_MEDIUM l_PreferredMedium = NdisMedium802_3; // Ethernet
  BOOLEAN l_MacFromRegistry = FALSE;
  UINT l_Index;
  NDIS_STATUS status;

  //====================================
  // Make sure adapter type is supported
  //====================================

  for (l_Index = 0;
       l_Index < p_MediaCount && p_Media[l_Index] != l_PreferredMedium;
       ++l_Index);

  if (l_Index == p_MediaCount)
    {
      DEBUGP (("[TAP] Unsupported adapter type [wanted: %d]\n",
	       l_PreferredMedium));
      return NDIS_STATUS_UNSUPPORTED_MEDIA;
    }

  *p_MediaIndex = l_Index;

  //=========================================
  // Allocate memory for TapAdapter structure
  //=========================================

  l_Adapter = MemAlloc (sizeof (TapAdapter), TRUE);

  if (l_Adapter == NULL)
    {
      DEBUGP (("[TAP] Couldn't allocate adapter memory\n"));
      return NDIS_STATUS_RESOURCES;
    }

  //==========================================
  // Inform the NDIS library about significant
  // features of our virtual NIC.
  //==========================================

  NdisMSetAttributesEx
    (p_AdapterHandle,
     (NDIS_HANDLE) l_Adapter,
     16,
     NDIS_ATTRIBUTE_DESERIALIZE
     | NDIS_ATTRIBUTE_IGNORE_PACKET_TIMEOUT
     | NDIS_ATTRIBUTE_IGNORE_REQUEST_TIMEOUT
     | NDIS_ATTRIBUTE_NO_HALT_ON_SUSPEND,
     NdisInterfaceInternal);

  //=====================================
  // Initialize simple Adapter parameters
  //=====================================

  l_Adapter->m_Lookahead = DEFAULT_PACKET_LOOKAHEAD;
  l_Adapter->m_Medium = l_PreferredMedium;
  l_Adapter->m_DeviceState = '?';
  l_Adapter->m_MiniportAdapterHandle = p_AdapterHandle;

  //==================================
  // Allocate spinlock for controlling
  // access to multicast address list.
  //==================================
  NdisAllocateSpinLock (&l_Adapter->m_MCLock);
  l_Adapter->m_MCLockAllocated = TRUE;

  //====================================================
  // Register a shutdown handler which will be called
  // on system restart/shutdown to halt our virtual NIC.
  //====================================================

  NdisMRegisterAdapterShutdownHandler (p_AdapterHandle, l_Adapter,
				       AdapterHalt);
  l_Adapter->m_RegisteredAdapterShutdownHandler = TRUE;

  //====================================
  // Allocate and construct adapter name
  //====================================

  if (RtlUnicodeStringToAnsiString (
       &l_Adapter->m_NameAnsi,
       &((PNDIS_MINIPORT_BLOCK) p_AdapterHandle)->MiniportName,
       TRUE) != STATUS_SUCCESS)
    {
      AdapterFreeResources (l_Adapter);
      return NDIS_STATUS_RESOURCES;
    }

  //============================================
  // Get parameters from registry which were set
  // in the adapter advanced properties dialog.
  //============================================
  {
    NDIS_STATUS status;
    NDIS_HANDLE configHandle;
    NDIS_CONFIGURATION_PARAMETER *parm;

    // set defaults in case our registry query fails
    l_Adapter->m_MTU = ETHERNET_MTU;
    l_Adapter->m_MediaStateAlwaysConnected = FALSE;
    l_Adapter->m_MediaState = FALSE;

    NdisOpenConfiguration (&status, &configHandle, p_ConfigurationHandle);
    if (status == NDIS_STATUS_SUCCESS)
      {
	/* Read MTU setting from registry */
	{
	  NDIS_STRING key = NDIS_STRING_CONST("MTU");
	  NdisReadConfiguration (&status, &parm, configHandle,
				 &key, NdisParameterInteger);
	  if (status == NDIS_STATUS_SUCCESS)
	    {
	      if (parm->ParameterType == NdisParameterInteger)
		{
		  int mtu = parm->ParameterData.IntegerData;
		  if (mtu < MINIMUM_MTU)
		    mtu = MINIMUM_MTU;
		  if (mtu > MAXIMUM_MTU)
		    mtu = MAXIMUM_MTU;
		  l_Adapter->m_MTU = mtu;
		}
	    }
	}

	/* Read Media Status setting from registry */
	{
	  NDIS_STRING key = NDIS_STRING_CONST("MediaStatus");
	  NdisReadConfiguration (&status, &parm, configHandle,
				 &key, NdisParameterInteger);
	  if (status == NDIS_STATUS_SUCCESS)
	    {
	      if (parm->ParameterType == NdisParameterInteger)
		{
		  if (parm->ParameterData.IntegerData)
		    {
		      l_Adapter->m_MediaStateAlwaysConnected = TRUE;
		      l_Adapter->m_MediaState = TRUE;
		    }
		}
	    }
	}

	/* Read optional MAC setting from registry */
	{
	  NDIS_STRING key = NDIS_STRING_CONST("MAC");
	  ANSI_STRING mac_string;
	  NdisReadConfiguration (&status, &parm, configHandle,
				 &key, NdisParameterString);
	  if (status == NDIS_STATUS_SUCCESS)
	    {
	      if (parm->ParameterType == NdisParameterString)
		{
		  if (RtlUnicodeStringToAnsiString (&mac_string, &parm->ParameterData.StringData, TRUE) == STATUS_SUCCESS)
		    {
		      l_MacFromRegistry = ParseMAC (l_Adapter->m_MAC, mac_string.Buffer);
		      RtlFreeAnsiString (&mac_string);
		    }
		}
	    }
	}

	NdisCloseConfiguration (configHandle);
      }

    DEBUGP (("[%s] MTU=%d\n", NAME (l_Adapter), l_Adapter->m_MTU));
  }

  //==================================
  // Store and update MAC address info
  //==================================

  if (!l_MacFromRegistry)
    GenerateRandomMac (l_Adapter->m_MAC, NAME (l_Adapter));

  DEBUGP (("[%s] Using MAC %x:%x:%x:%x:%x:%x\n",
	    NAME (l_Adapter),
	    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]));

  //==================
  // Set broadcast MAC
  //==================
  {