src/drivers/ndis_events.c - vendor/opensource/hostap - Git at Google

 /*
  * ndis_events - Receive NdisMIndicateStatus() events using WMI
  * Copyright (c) 2004-2006, Jouni Malinen <j@w1.fi>
  *
  * This software may be distributed under the terms of the BSD license.
  * See README for more details.
  */

 #define _WIN32_WINNT    0x0400

 #include "includes.h"

 #ifndef COBJMACROS
 #define COBJMACROS
 #endif /* COBJMACROS */
 #include <wbemidl.h>

 #include "common.h"


 static int wmi_refcnt = 0;
 static int wmi_first = 1;

 struct ndis_events_data {
 	IWbemObjectSink sink;
 	IWbemObjectSinkVtbl sink_vtbl;

 	IWbemServices *pSvc;
 	IWbemLocator *pLoc;

 	HANDLE read_pipe, write_pipe, event_avail;
 	UINT ref;
 	int terminating;
 	char *ifname; /* {GUID..} */
 	WCHAR *adapter_desc;
 };

 #define BstrAlloc(x) (x) ? SysAllocString(x) : NULL
 #define BstrFree(x) if (x) SysFreeString(x)

 /* WBEM / WMI wrapper functions, to perform in-place conversion of WCHARs to
  * BSTRs */
 HRESULT STDMETHODCALLTYPE call_IWbemServices_ExecQuery(
 	IWbemServices *pSvc, LPCWSTR strQueryLanguage, LPCWSTR strQuery,
 	long lFlags, IWbemContext *pCtx, IEnumWbemClassObject **ppEnum)
 {
 	BSTR bsQueryLanguage, bsQuery;
 	HRESULT hr;

 	bsQueryLanguage = BstrAlloc(strQueryLanguage);
 	bsQuery = BstrAlloc(strQuery);

 	hr = IWbemServices_ExecQuery(pSvc, bsQueryLanguage, bsQuery, lFlags,
 				     pCtx, ppEnum);

 	BstrFree(bsQueryLanguage);
 	BstrFree(bsQuery);

 	return hr;
 }


 HRESULT STDMETHODCALLTYPE call_IWbemServices_ExecNotificationQueryAsync(
 	IWbemServices *pSvc, LPCWSTR strQueryLanguage, LPCWSTR strQuery,
 	long lFlags, IWbemContext *pCtx, IWbemObjectSink *pResponseHandler)
 {
 	BSTR bsQueryLanguage, bsQuery;
 	HRESULT hr;

 	bsQueryLanguage = BstrAlloc(strQueryLanguage);
 	bsQuery = BstrAlloc(strQuery);

 	hr = IWbemServices_ExecNotificationQueryAsync(pSvc, bsQueryLanguage,
 						      bsQuery, lFlags, pCtx,
 						      pResponseHandler);

 	BstrFree(bsQueryLanguage);
 	BstrFree(bsQuery);

 	return hr;
 }


 HRESULT STDMETHODCALLTYPE call_IWbemLocator_ConnectServer(
 	IWbemLocator *pLoc, LPCWSTR strNetworkResource, LPCWSTR strUser,
 	LPCWSTR strPassword, LPCWSTR strLocale, long lSecurityFlags,
 	LPCWSTR strAuthority, IWbemContext *pCtx, IWbemServices **ppNamespace)
 {
 	BSTR bsNetworkResource, bsUser, bsPassword, bsLocale, bsAuthority;
 	HRESULT hr;

 	bsNetworkResource = BstrAlloc(strNetworkResource);
 	bsUser = BstrAlloc(strUser);
 	bsPassword = BstrAlloc(strPassword);
 	bsLocale = BstrAlloc(strLocale);
 	bsAuthority = BstrAlloc(strAuthority);

 	hr = IWbemLocator_ConnectServer(pLoc, bsNetworkResource, bsUser,
 					bsPassword, bsLocale, lSecurityFlags,
 					bsAuthority, pCtx, ppNamespace);

 	BstrFree(bsNetworkResource);
 	BstrFree(bsUser);
 	BstrFree(bsPassword);
 	BstrFree(bsLocale);
 	BstrFree(bsAuthority);

 	return hr;
 }


 enum event_types { EVENT_CONNECT, EVENT_DISCONNECT, EVENT_MEDIA_SPECIFIC,
 		   EVENT_ADAPTER_ARRIVAL, EVENT_ADAPTER_REMOVAL };

 static int ndis_events_get_adapter(struct ndis_events_data *events,
 				   const char *ifname, const char *desc);


 static int ndis_events_constructor(struct ndis_events_data *events)
 {
 	events->ref = 1;

 	if (!CreatePipe(&events->read_pipe, &events->write_pipe, NULL, 512)) {
 		wpa_printf(MSG_ERROR, "CreatePipe() failed: %d",
 			   (int) GetLastError());
 		return -1;
 	}
 	events->event_avail = CreateEvent(NULL, TRUE, FALSE, NULL);
 	if (events->event_avail == NULL) {
 		wpa_printf(MSG_ERROR, "CreateEvent() failed: %d",
 			   (int) GetLastError());
 		CloseHandle(events->read_pipe);
 		CloseHandle(events->write_pipe);
 		return -1;
 	}

 	return 0;
 }


 static void ndis_events_destructor(struct ndis_events_data *events)
 {
 	CloseHandle(events->read_pipe);
 	CloseHandle(events->write_pipe);
 	CloseHandle(events->event_avail);
 	IWbemServices_Release(events->pSvc);
 	IWbemLocator_Release(events->pLoc);
 	if (--wmi_refcnt == 0)
 		CoUninitialize();
 }


 static HRESULT STDMETHODCALLTYPE
 ndis_events_query_interface(IWbemObjectSink *this, REFIID riid, void **obj)
 {
 	*obj = NULL;

 	if (IsEqualIID(riid, &IID_IUnknown) ||
 	    IsEqualIID(riid, &IID_IWbemObjectSink)) {
 		*obj = this;
 		IWbemObjectSink_AddRef(this);
 		return NOERROR;
 	}

 	return E_NOINTERFACE;
 }


 static ULONG STDMETHODCALLTYPE ndis_events_add_ref(IWbemObjectSink *this)
 {
 	struct ndis_events_data *events = (struct ndis_events_data *) this;
 	return ++events->ref;
 }


 static ULONG STDMETHODCALLTYPE ndis_events_release(IWbemObjectSink *this)
 {
 	struct ndis_events_data *events = (struct ndis_events_data *) this;

 	if (--events->ref != 0)
 		return events->ref;

 	ndis_events_destructor(events);
 	wpa_printf(MSG_DEBUG, "ndis_events: terminated");
 	os_free(events->adapter_desc);
 	os_free(events->ifname);
 	os_free(events);
 	return 0;
 }


 static int ndis_events_send_event(struct ndis_events_data *events,
 				  enum event_types type,
 				  char *data, size_t data_len)
 {
 	char buf[512], *pos, *end;
 	int _type;
 	DWORD written;

 	end = buf + sizeof(buf);
 	_type = (int) type;
 	os_memcpy(buf, &_type, sizeof(_type));
 	pos = buf + sizeof(_type);

 	if (data) {
 		if (2 + data_len > (size_t) (end - pos)) {
 			wpa_printf(MSG_DEBUG, "Not enough room for send_event "
 				   "data (%d)", data_len);
 			return -1;
 		}
 		*pos++ = data_len >> 8;
 		*pos++ = data_len & 0xff;
 		os_memcpy(pos, data, data_len);
 		pos += data_len;
 	}

 	if (WriteFile(events->write_pipe, buf, pos - buf, &written, NULL)) {
 		SetEvent(events->event_avail);
 		return 0;
 	}
 	wpa_printf(MSG_INFO, "WriteFile() failed: %d", (int) GetLastError());
 	return -1;
 }


 static void ndis_events_media_connect(struct ndis_events_data *events)
 {
 	wpa_printf(MSG_DEBUG, "MSNdis_StatusMediaConnect");
 	ndis_events_send_event(events, EVENT_CONNECT, NULL, 0);
 }


 static void ndis_events_media_disconnect(struct ndis_events_data *events)
 {
 	wpa_printf(MSG_DEBUG, "MSNdis_StatusMediaDisconnect");
 	ndis_events_send_event(events, EVENT_DISCONNECT, NULL, 0);
 }


 static void ndis_events_media_specific(struct ndis_events_data *events,
 				       IWbemClassObject *pObj)
 {
 	VARIANT vt;
 	HRESULT hr;
 	LONG lower, upper, k;
 	UCHAR ch;
 	char *data, *pos;
 	size_t data_len;

 	wpa_printf(MSG_DEBUG, "MSNdis_StatusMediaSpecificIndication");

 	/* This is the StatusBuffer from NdisMIndicateStatus() call */
 	hr = IWbemClassObject_Get(pObj, L"NdisStatusMediaSpecificIndication",
 				  0, &vt, NULL, NULL);
 	if (FAILED(hr)) {
 		wpa_printf(MSG_DEBUG, "Could not get "
 			   "NdisStatusMediaSpecificIndication from "
 			   "the object?!");
 		return;
 	}

 	SafeArrayGetLBound(V_ARRAY(&vt), 1, &lower);
 	SafeArrayGetUBound(V_ARRAY(&vt), 1, &upper);
 	data_len = upper - lower + 1;
 	data = os_malloc(data_len);
 	if (data == NULL) {
 		wpa_printf(MSG_DEBUG, "Failed to allocate buffer for event "
 			   "data");
 		VariantClear(&vt);
 		return;
 	}

 	pos = data;
 	for (k = lower; k <= upper; k++) {
 		SafeArrayGetElement(V_ARRAY(&vt), &k, &ch);
 		*pos++ = ch;
 	}
 	wpa_hexdump(MSG_DEBUG, "MediaSpecificEvent", (u8 *) data, data_len);

 	VariantClear(&vt);

 	ndis_events_send_event(events, EVENT_MEDIA_SPECIFIC, data, data_len);

 	os_free(data);
 }


 static void ndis_events_adapter_arrival(struct ndis_events_data *events)
 {
 	wpa_printf(MSG_DEBUG, "MSNdis_NotifyAdapterArrival");
 	ndis_events_send_event(events, EVENT_ADAPTER_ARRIVAL, NULL, 0);
 }


 static void ndis_events_adapter_removal(struct ndis_events_data *events)
 {
 	wpa_printf(MSG_DEBUG, "MSNdis_NotifyAdapterRemoval");
 	ndis_events_send_event(events, EVENT_ADAPTER_REMOVAL, NULL, 0);
 }


 static HRESULT STDMETHODCALLTYPE
 ndis_events_indicate(IWbemObjectSink *this, long lObjectCount,
 		     IWbemClassObject __RPC_FAR *__RPC_FAR *ppObjArray)
 {
 	struct ndis_events_data *events = (struct ndis_events_data *) this;
 	long i;

 	if (events->terminating) {
 		wpa_printf(MSG_DEBUG, "ndis_events_indicate: Ignore "
 			   "indication - terminating");
 		return WBEM_NO_ERROR;
 	}
 	/* wpa_printf(MSG_DEBUG, "Notification received - %d object(s)",
 	   lObjectCount); */

 	for (i = 0; i < lObjectCount; i++) {
 		IWbemClassObject *pObj = ppObjArray[i];
 		HRESULT hr;
 		VARIANT vtClass, vt;

 		hr = IWbemClassObject_Get(pObj, L"__CLASS", 0, &vtClass, NULL,
 					  NULL);
 		if (FAILED(hr)) {
 			wpa_printf(MSG_DEBUG, "Failed to get __CLASS from "
 				   "event.");
 			break;
 		}
 		/* wpa_printf(MSG_DEBUG, "CLASS: '%S'", vtClass.bstrVal); */

 		hr = IWbemClassObject_Get(pObj, L"InstanceName", 0, &vt, NULL,
 					  NULL);
 		if (FAILED(hr)) {
 			wpa_printf(MSG_DEBUG, "Failed to get InstanceName "
 				   "from event.");
 			VariantClear(&vtClass);
 			break;
 		}

 		if (wcscmp(vtClass.bstrVal,
 			   L"MSNdis_NotifyAdapterArrival") == 0) {
 			wpa_printf(MSG_DEBUG, "ndis_events_indicate: Try to "
 				   "update adapter description since it may "
 				   "have changed with new adapter instance");
 			ndis_events_get_adapter(events, events->ifname, NULL);
 		}

 		if (wcscmp(events->adapter_desc, vt.bstrVal) != 0) {
 			wpa_printf(MSG_DEBUG, "ndis_events_indicate: Ignore "
 				   "indication for foreign adapter: "
 				   "InstanceName: '%S' __CLASS: '%S'",
 				   vt.bstrVal, vtClass.bstrVal);
 			VariantClear(&vtClass);
 			VariantClear(&vt);
 			continue;
 		}
 		VariantClear(&vt);

 		if (wcscmp(vtClass.bstrVal,
 			   L"MSNdis_StatusMediaSpecificIndication") == 0) {
 			ndis_events_media_specific(events, pObj);
 		} else if (wcscmp(vtClass.bstrVal,
 				  L"MSNdis_StatusMediaConnect") == 0) {
 			ndis_events_media_connect(events);
 		} else if (wcscmp(vtClass.bstrVal,
 				  L"MSNdis_StatusMediaDisconnect") == 0) {
 			ndis_events_media_disconnect(events);
 		} else if (wcscmp(vtClass.bstrVal,
 				  L"MSNdis_NotifyAdapterArrival") == 0) {
 			ndis_events_adapter_arrival(events);
 		} else if (wcscmp(vtClass.bstrVal,
 				  L"MSNdis_NotifyAdapterRemoval") == 0) {
 			ndis_events_adapter_removal(events);
 		} else {
 			wpa_printf(MSG_DEBUG, "Unepected event - __CLASS: "
 				   "'%S'", vtClass.bstrVal);
 		}

 		VariantClear(&vtClass);
 	}

 	return WBEM_NO_ERROR;
 }


 static HRESULT STDMETHODCALLTYPE
 ndis_events_set_status(IWbemObjectSink *this, long lFlags, HRESULT hResult,
 		       BSTR strParam, IWbemClassObject __RPC_FAR *pObjParam)
 {
 	return WBEM_NO_ERROR;
 }


 static int notification_query(IWbemObjectSink *pDestSink,
 			      IWbemServices *pSvc, const char *class_name)
 {
 	HRESULT hr;
 	WCHAR query[256];

 	_snwprintf(query, 256,
 		  L"SELECT * FROM %S", class_name);
 	wpa_printf(MSG_DEBUG, "ndis_events: WMI: %S", query);
 	hr = call_IWbemServices_ExecNotificationQueryAsync(
 		pSvc, L"WQL", query, 0, 0, pDestSink);
 	if (FAILED(hr)) {
 		wpa_printf(MSG_DEBUG, "ExecNotificationQueryAsync for %s "
 			   "failed with hresult of 0x%x",
 			   class_name, (int) hr);
 		return -1;
 	}

 	return 0;
 }


 static int register_async_notification(IWbemObjectSink *pDestSink,
 				       IWbemServices *pSvc)
 {
 	int i;
 	const char *class_list[] = {
 		"MSNdis_StatusMediaConnect",
 		"MSNdis_StatusMediaDisconnect",
 		"MSNdis_StatusMediaSpecificIndication",
 		"MSNdis_NotifyAdapterArrival",
 		"MSNdis_NotifyAdapterRemoval",
 		NULL
 	};

 	for (i = 0; class_list[i]; i++) {
 		if (notification_query(pDestSink, pSvc, class_list[i]) < 0)
 			return -1;
 	}

 	return 0;
 }


 void ndis_events_deinit(struct ndis_events_data *events)
 {
 	events->terminating = 1;
 	IWbemServices_CancelAsyncCall(events->pSvc, &events->sink);
 	IWbemObjectSink_Release(&events->sink);
 	/*
 	 * Rest of deinitialization is done in ndis_events_destructor() once
 	 * all reference count drops to zero.
 	 */
 }


 static int ndis_events_use_desc(struct ndis_events_data *events,
 				const char *desc)
 {
 	char *tmp, *pos;
 	size_t len;

 	if (desc == NULL) {
 		if (events->adapter_desc == NULL)
 			return -1;
 		/* Continue using old description */
 		return 0;
 	}

 	tmp = os_strdup(desc);
 	if (tmp == NULL)
 		return -1;

 	pos = os_strstr(tmp, " (Microsoft's Packet Scheduler)");
 	if (pos)
 		*pos = '\0';

 	len = os_strlen(tmp);
 	events->adapter_desc = os_malloc((len + 1) * sizeof(WCHAR));
 	if (events->adapter_desc == NULL) {
 		os_free(tmp);
 		return -1;
 	}
 	_snwprintf(events->adapter_desc, len + 1, L"%S", tmp);
 	os_free(tmp);
 	return 0;
 }


 static int ndis_events_get_adapter(struct ndis_events_data *events,
 				   const char *ifname, const char *desc)
 {
 	HRESULT hr;
 	IWbemServices *pSvc;
 #define MAX_QUERY_LEN 256
 	WCHAR query[MAX_QUERY_LEN];
 	IEnumWbemClassObject *pEnumerator;
 	IWbemClassObject *pObj;
 	ULONG uReturned;
 	VARIANT vt;
 	int len, pos;

 	/*
 	 * Try to get adapter descriptor through WMI CIMv2 Win32_NetworkAdapter
 	 * to have better probability of matching with InstanceName from
 	 * MSNdis events. If this fails, use the provided description.
 	 */

 	os_free(events->adapter_desc);
 	events->adapter_desc = NULL;

 	hr = call_IWbemLocator_ConnectServer(
 		events->pLoc, L"ROOT\\CIMV2", NULL, NULL, 0, 0, 0, 0, &pSvc);
 	if (FAILED(hr)) {
 		wpa_printf(MSG_ERROR, "ndis_events: Could not connect to WMI "
 			   "server (ROOT\\CIMV2) - error 0x%x", (int) hr);
 		return ndis_events_use_desc(events, desc);
 	}
 	wpa_printf(MSG_DEBUG, "ndis_events: Connected to ROOT\\CIMV2.");

 	_snwprintf(query, MAX_QUERY_LEN,
 		  L"SELECT Index FROM Win32_NetworkAdapterConfiguration "
 		  L"WHERE SettingID='%S'", ifname);
 	wpa_printf(MSG_DEBUG, "ndis_events: WMI: %S", query);

 	hr = call_IWbemServices_ExecQuery(
 		pSvc, L"WQL", query,
 		WBEM_FLAG_FORWARD_ONLY | WBEM_FLAG_RETURN_IMMEDIATELY,
 		NULL, &pEnumerator);
 	if (!SUCCEEDED(hr)) {
 		wpa_printf(MSG_DEBUG, "ndis_events: Failed to query interface "
 			   "GUID from Win32_NetworkAdapterConfiguration: "
 			   "0x%x", (int) hr);
 		IWbemServices_Release(pSvc);
 		return ndis_events_use_desc(events, desc);
 	}

 	uReturned = 0;
 	hr = IEnumWbemClassObject_Next(pEnumerator, WBEM_INFINITE, 1,
 				       &pObj, &uReturned);
 	if (!SUCCEEDED(hr) || uReturned == 0) {
 		wpa_printf(MSG_DEBUG, "ndis_events: Failed to find interface "
 			   "GUID from Win32_NetworkAdapterConfiguration: "
 			   "0x%x", (int) hr);
 		IEnumWbemClassObject_Release(pEnumerator);
 		IWbemServices_Release(pSvc);
 		return ndis_events_use_desc(events, desc);
 	}
 	IEnumWbemClassObject_Release(pEnumerator);

 	VariantInit(&vt);
 	hr = IWbemClassObject_Get(pObj, L"Index", 0, &vt, NULL, NULL);
 	if (!SUCCEEDED(hr)) {
 		wpa_printf(MSG_DEBUG, "ndis_events: Failed to get Index from "
 			   "Win32_NetworkAdapterConfiguration: 0x%x",
 			   (int) hr);
 		IWbemServices_Release(pSvc);
 		return ndis_events_use_desc(events, desc);
 	}

 	_snwprintf(query, MAX_QUERY_LEN,
 		  L"SELECT Name,PNPDeviceID FROM Win32_NetworkAdapter WHERE "
 		  L"Index=%d",
 		  vt.uintVal);
 	wpa_printf(MSG_DEBUG, "ndis_events: WMI: %S", query);
 	VariantClear(&vt);
 	IWbemClassObject_Release(pObj);

 	hr = call_IWbemServices_ExecQuery(
 		pSvc, L"WQL", query,
 		WBEM_FLAG_FORWARD_ONLY | WBEM_FLAG_RETURN_IMMEDIATELY,
 		NULL, &pEnumerator);
 	if (!SUCCEEDED(hr)) {
 		wpa_printf(MSG_DEBUG, "ndis_events: Failed to query interface "
 			   "from Win32_NetworkAdapter: 0x%x", (int) hr);
 		IWbemServices_Release(pSvc);
 		return ndis_events_use_desc(events, desc);
 	}

 	uReturned = 0;
 	hr = IEnumWbemClassObject_Next(pEnumerator, WBEM_INFINITE, 1,
 				       &pObj, &uReturned);
 	if (!SUCCEEDED(hr) || uReturned == 0) {
 		wpa_printf(MSG_DEBUG, "ndis_events: Failed to find interface "
 			   "from Win32_NetworkAdapter: 0x%x", (int) hr);
 		IEnumWbemClassObject_Release(pEnumerator);
 		IWbemServices_Release(pSvc);
 		return ndis_events_use_desc(events, desc);
 	}
 	IEnumWbemClassObject_Release(pEnumerator);

 	hr = IWbemClassObject_Get(pObj, L"Name", 0, &vt, NULL, NULL);
 	if (!SUCCEEDED(hr)) {
 		wpa_printf(MSG_DEBUG, "ndis_events: Failed to get Name from "
 			   "Win32_NetworkAdapter: 0x%x", (int) hr);
 		IWbemClassObject_Release(pObj);
 		IWbemServices_Release(pSvc);
 		return ndis_events_use_desc(events, desc);
 	}

 	wpa_printf(MSG_DEBUG, "ndis_events: Win32_NetworkAdapter::Name='%S'",
 		   vt.bstrVal);
 	events->adapter_desc = _wcsdup(vt.bstrVal);
 	VariantClear(&vt);

 	/*
 	 * Try to get even better candidate for matching with InstanceName
 	 * from Win32_PnPEntity. This is needed at least for some USB cards
 	 * that can change the InstanceName whenever being unplugged and
 	 * plugged again.
 	 */

 	hr = IWbemClassObject_Get(pObj, L"PNPDeviceID", 0, &vt, NULL, NULL);
 	if (!SUCCEEDED(hr)) {
 		wpa_printf(MSG_DEBUG, "ndis_events: Failed to get PNPDeviceID "
 			   "from Win32_NetworkAdapter: 0x%x", (int) hr);
 		IWbemClassObject_Release(pObj);
 		IWbemServices_Release(pSvc);
 		if (events->adapter_desc == NULL)
 			return ndis_events_use_desc(events, desc);
 		return 0; /* use Win32_NetworkAdapter::Name */
 	}

 	wpa_printf(MSG_DEBUG, "ndis_events: Win32_NetworkAdapter::PNPDeviceID="
 		   "'%S'", vt.bstrVal);

 	len = _snwprintf(query, MAX_QUERY_LEN,
 			L"SELECT Name FROM Win32_PnPEntity WHERE DeviceID='");
 	if (len < 0 || len >= MAX_QUERY_LEN - 1) {
 		VariantClear(&vt);
 		IWbemClassObject_Release(pObj);
 		IWbemServices_Release(pSvc);
 		if (events->adapter_desc == NULL)
 			return ndis_events_use_desc(events, desc);
 		return 0; /* use Win32_NetworkAdapter::Name */
 	}

 	/* Escape \ as \\ */
 	for (pos = 0; vt.bstrVal[pos] && len < MAX_QUERY_LEN - 2; pos++) {
 		if (vt.bstrVal[pos] == '\\') {
 			if (len >= MAX_QUERY_LEN - 3)
 				break;
 			query[len++] = '\\';
 		}
 		query[len++] = vt.bstrVal[pos];
 	}
 	query[len++] = L'\'';
 	query[len] = L'\0';
 	VariantClear(&vt);
 	IWbemClassObject_Release(pObj);
 	wpa_printf(MSG_DEBUG, "ndis_events: WMI: %S", query);

 	hr = call_IWbemServices_ExecQuery(
 		pSvc, L"WQL", query,
 		WBEM_FLAG_FORWARD_ONLY | WBEM_FLAG_RETURN_IMMEDIATELY,
 		NULL, &pEnumerator);
 	if (!SUCCEEDED(hr)) {
 		wpa_printf(MSG_DEBUG, "ndis_events: Failed to query interface "
 			   "Name from Win32_PnPEntity: 0x%x", (int) hr);
 		IWbemServices_Release(pSvc);
 		if (events->adapter_desc == NULL)
 			return ndis_events_use_desc(events, desc);
 		return 0; /* use Win32_NetworkAdapter::Name */
 	}

 	uReturned = 0;
 	hr = IEnumWbemClassObject_Next(pEnumerator, WBEM_INFINITE, 1,
 				       &pObj, &uReturned);
 	if (!SUCCEEDED(hr) || uReturned == 0) {
 		wpa_printf(MSG_DEBUG, "ndis_events: Failed to find interface "
 			   "from Win32_PnPEntity: 0x%x", (int) hr);
 		IEnumWbemClassObject_Release(pEnumerator);
 		IWbemServices_Release(pSvc);
 		if (events->adapter_desc == NULL)
 			return ndis_events_use_desc(events, desc);
 		return 0; /* use Win32_NetworkAdapter::Name */
 	}
 	IEnumWbemClassObject_Release(pEnumerator);

 	hr = IWbemClassObject_Get(pObj, L"Name", 0, &vt, NULL, NULL);
 	if (!SUCCEEDED(hr)) {
 		wpa_printf(MSG_DEBUG, "ndis_events: Failed to get Name from "
 			   "Win32_PnPEntity: 0x%x", (int) hr);
 		IWbemClassObject_Release(pObj);
 		IWbemServices_Release(pSvc);
 		if (events->adapter_desc == NULL)
 			return ndis_events_use_desc(events, desc);
 		return 0; /* use Win32_NetworkAdapter::Name */
 	}

 	wpa_printf(MSG_DEBUG, "ndis_events: Win32_PnPEntity::Name='%S'",
 		   vt.bstrVal);
 	os_free(events->adapter_desc);
 	events->adapter_desc = _wcsdup(vt.bstrVal);
 	VariantClear(&vt);

 	IWbemClassObject_Release(pObj);

 	IWbemServices_Release(pSvc);

 	if (events->adapter_desc == NULL)
 		return ndis_events_use_desc(events, desc);

 	return 0;
 }


 struct ndis_events_data *
 ndis_events_init(HANDLE *read_pipe, HANDLE *event_avail,
 		 const char *ifname, const char *desc)
 {
 	HRESULT hr;
 	IWbemObjectSink *pSink;
 	struct ndis_events_data *events;

 	events = os_zalloc(sizeof(*events));
 	if (events == NULL) {
 		wpa_printf(MSG_ERROR, "Could not allocate sink for events.");
 		return NULL;
 	}
 	events->ifname = os_strdup(ifname);
 	if (events->ifname == NULL) {
 		os_free(events);
 		return NULL;
 	}

 	if (wmi_refcnt++ == 0) {
 		hr = CoInitializeEx(0, COINIT_MULTITHREADED);
 		if (FAILED(hr)) {
 			wpa_printf(MSG_ERROR, "CoInitializeEx() failed - "
 				   "returned 0x%x", (int) hr);
 			os_free(events);
 			return NULL;
 		}
 	}

 	if (wmi_first) {
 		/* CoInitializeSecurity() must be called once and only once
 		 * per process, so let's use wmi_first flag to protect against
 		 * multiple calls. */
 		wmi_first = 0;

 		hr = CoInitializeSecurity(NULL, -1, NULL, NULL,
 					  RPC_C_AUTHN_LEVEL_PKT_PRIVACY,
 					  RPC_C_IMP_LEVEL_IMPERSONATE,
 					  NULL, EOAC_SECURE_REFS, NULL);
 		if (FAILED(hr)) {
 			wpa_printf(MSG_ERROR, "CoInitializeSecurity() failed "
 				   "- returned 0x%x", (int) hr);
 			os_free(events);
 			return NULL;
 		}
 	}

 	hr = CoCreateInstance(&CLSID_WbemLocator, 0, CLSCTX_INPROC_SERVER,
 			      &IID_IWbemLocator,
 			      (LPVOID *) (void *) &events->pLoc);
 	if (FAILED(hr)) {
 		wpa_printf(MSG_ERROR, "CoCreateInstance() failed - returned "
 			   "0x%x", (int) hr);
 		CoUninitialize();
 		os_free(events);
 		return NULL;
 	}

 	if (ndis_events_get_adapter(events, ifname, desc) < 0) {
 		CoUninitialize();
 		os_free(events);
 		return NULL;
 	}
 	wpa_printf(MSG_DEBUG, "ndis_events: use adapter descriptor '%S'",
 		   events->adapter_desc);

 	hr = call_IWbemLocator_ConnectServer(
 		events->pLoc, L"ROOT\\WMI", NULL, NULL,
 		0, 0, 0, 0, &events->pSvc);
 	if (FAILED(hr)) {
 		wpa_printf(MSG_ERROR, "Could not connect to server - error "
 			   "0x%x", (int) hr);
 		CoUninitialize();
 		os_free(events->adapter_desc);
 		os_free(events);
 		return NULL;
 	}
 	wpa_printf(MSG_DEBUG, "Connected to ROOT\\WMI.");

 	ndis_events_constructor(events);
 	pSink = &events->sink;
 	pSink->lpVtbl = &events->sink_vtbl;
 	events->sink_vtbl.QueryInterface = ndis_events_query_interface;
 	events->sink_vtbl.AddRef = ndis_events_add_ref;
 	events->sink_vtbl.Release = ndis_events_release;
 	events->sink_vtbl.Indicate = ndis_events_indicate;
 	events->sink_vtbl.SetStatus = ndis_events_set_status;

 	if (register_async_notification(pSink, events->pSvc) < 0) {
 		wpa_printf(MSG_DEBUG, "Failed to register async "
 			   "notifications");
 		ndis_events_destructor(events);
 		os_free(events->adapter_desc);
 		os_free(events);
 		return NULL;
 	}

 	*read_pipe = events->read_pipe;
 	*event_avail = events->event_avail;

 	return events;
 }
	/*
	* ndis_events - Receive NdisMIndicateStatus() events using WMI
	* Copyright (c) 2004-2006, Jouni Malinen <j@w1.fi>
	*
	* This software may be distributed under the terms of the BSD license.
	* See README for more details.
	*/

	#define _WIN32_WINNT 0x0400

	#include "includes.h"

	#ifndef COBJMACROS
	#define COBJMACROS
	#endif /* COBJMACROS */
	#include <wbemidl.h>

	#include "common.h"


	static int wmi_refcnt = 0;
	static int wmi_first = 1;

	struct ndis_events_data {
	IWbemObjectSink sink;
	IWbemObjectSinkVtbl sink_vtbl;

	IWbemServices *pSvc;
	IWbemLocator *pLoc;

	HANDLE read_pipe, write_pipe, event_avail;
	UINT ref;
	int terminating;
	char ifname; / {GUID..} */
	WCHAR *adapter_desc;
	};

	#define BstrAlloc(x) (x) ? SysAllocString(x) : NULL
	#define BstrFree(x) if (x) SysFreeString(x)

	/* WBEM / WMI wrapper functions, to perform in-place conversion of WCHARs to
	* BSTRs */
	HRESULT STDMETHODCALLTYPE call_IWbemServices_ExecQuery(
	IWbemServices *pSvc, LPCWSTR strQueryLanguage, LPCWSTR strQuery,
	long lFlags, IWbemContext pCtx, IEnumWbemClassObject *ppEnum)
	{
	BSTR bsQueryLanguage, bsQuery;
	HRESULT hr;

	bsQueryLanguage = BstrAlloc(strQueryLanguage);
	bsQuery = BstrAlloc(strQuery);

	hr = IWbemServices_ExecQuery(pSvc, bsQueryLanguage, bsQuery, lFlags,
	pCtx, ppEnum);

	BstrFree(bsQueryLanguage);
	BstrFree(bsQuery);

	return hr;
	}


	HRESULT STDMETHODCALLTYPE call_IWbemServices_ExecNotificationQueryAsync(
	IWbemServices *pSvc, LPCWSTR strQueryLanguage, LPCWSTR strQuery,
	long lFlags, IWbemContext pCtx, IWbemObjectSink pResponseHandler)
	{
	BSTR bsQueryLanguage, bsQuery;
	HRESULT hr;

	bsQueryLanguage = BstrAlloc(strQueryLanguage);
	bsQuery = BstrAlloc(strQuery);

	hr = IWbemServices_ExecNotificationQueryAsync(pSvc, bsQueryLanguage,
	bsQuery, lFlags, pCtx,
	pResponseHandler);

	BstrFree(bsQueryLanguage);
	BstrFree(bsQuery);

	return hr;
	}


	HRESULT STDMETHODCALLTYPE call_IWbemLocator_ConnectServer(
	IWbemLocator *pLoc, LPCWSTR strNetworkResource, LPCWSTR strUser,
	LPCWSTR strPassword, LPCWSTR strLocale, long lSecurityFlags,
	LPCWSTR strAuthority, IWbemContext pCtx, IWbemServices *ppNamespace)
	{
	BSTR bsNetworkResource, bsUser, bsPassword, bsLocale, bsAuthority;
	HRESULT hr;

	bsNetworkResource = BstrAlloc(strNetworkResource);
	bsUser = BstrAlloc(strUser);
	bsPassword = BstrAlloc(strPassword);
	bsLocale = BstrAlloc(strLocale);
	bsAuthority = BstrAlloc(strAuthority);

	hr = IWbemLocator_ConnectServer(pLoc, bsNetworkResource, bsUser,
	bsPassword, bsLocale, lSecurityFlags,
	bsAuthority, pCtx, ppNamespace);

	BstrFree(bsNetworkResource);
	BstrFree(bsUser);
	BstrFree(bsPassword);
	BstrFree(bsLocale);
	BstrFree(bsAuthority);

	return hr;
	}


	enum event_types { EVENT_CONNECT, EVENT_DISCONNECT, EVENT_MEDIA_SPECIFIC,
	EVENT_ADAPTER_ARRIVAL, EVENT_ADAPTER_REMOVAL };

	static int ndis_events_get_adapter(struct ndis_events_data *events,
	const char ifname, const char desc);


	static int ndis_events_constructor(struct ndis_events_data *events)
	{
	events->ref = 1;

	if (!CreatePipe(&events->read_pipe, &events->write_pipe, NULL, 512)) {
	wpa_printf(MSG_ERROR, "CreatePipe() failed: %d",
	(int) GetLastError());
	return -1;
	}
	events->event_avail = CreateEvent(NULL, TRUE, FALSE, NULL);
	if (events->event_avail == NULL) {
	wpa_printf(MSG_ERROR, "CreateEvent() failed: %d",
	(int) GetLastError());
	CloseHandle(events->read_pipe);
	CloseHandle(events->write_pipe);
	return -1;
	}

	return 0;
	}


	static void ndis_events_destructor(struct ndis_events_data *events)
	{
	CloseHandle(events->read_pipe);
	CloseHandle(events->write_pipe);
	CloseHandle(events->event_avail);
	IWbemServices_Release(events->pSvc);
	IWbemLocator_Release(events->pLoc);
	if (--wmi_refcnt == 0)
	CoUninitialize();
	}


	static HRESULT STDMETHODCALLTYPE
	ndis_events_query_interface(IWbemObjectSink this, REFIID riid, void *obj)
	{
	*obj = NULL;

	if (IsEqualIID(riid, &IID_IUnknown) \|\|
	IsEqualIID(riid, &IID_IWbemObjectSink)) {
	*obj = this;
	IWbemObjectSink_AddRef(this);
	return NOERROR;
	}

	return E_NOINTERFACE;
	}


	static ULONG STDMETHODCALLTYPE ndis_events_add_ref(IWbemObjectSink *this)
	{
	struct ndis_events_data events = (struct ndis_events_data ) this;
	return ++events->ref;
	}


	static ULONG STDMETHODCALLTYPE ndis_events_release(IWbemObjectSink *this)
	{
	struct ndis_events_data events = (struct ndis_events_data ) this;

	if (--events->ref != 0)
	return events->ref;

	ndis_events_destructor(events);
	wpa_printf(MSG_DEBUG, "ndis_events: terminated");
	os_free(events->adapter_desc);
	os_free(events->ifname);
	os_free(events);
	return 0;
	}


	static int ndis_events_send_event(struct ndis_events_data *events,
	enum event_types type,
	char *data, size_t data_len)
	{
	char buf[512], pos, end;
	int _type;
	DWORD written;

	end = buf + sizeof(buf);
	_type = (int) type;
	os_memcpy(buf, &_type, sizeof(_type));
	pos = buf + sizeof(_type);

	if (data) {
	if (2 + data_len > (size_t) (end - pos)) {
	wpa_printf(MSG_DEBUG, "Not enough room for send_event "
	"data (%d)", data_len);
	return -1;
	}
	*pos++ = data_len >> 8;
	*pos++ = data_len & 0xff;
	os_memcpy(pos, data, data_len);
	pos += data_len;
	}

	if (WriteFile(events->write_pipe, buf, pos - buf, &written, NULL)) {
	SetEvent(events->event_avail);
	return 0;
	}
	wpa_printf(MSG_INFO, "WriteFile() failed: %d", (int) GetLastError());
	return -1;
	}


	static void ndis_events_media_connect(struct ndis_events_data *events)
	{
	wpa_printf(MSG_DEBUG, "MSNdis_StatusMediaConnect");
	ndis_events_send_event(events, EVENT_CONNECT, NULL, 0);
	}


	static void ndis_events_media_disconnect(struct ndis_events_data *events)
	{
	wpa_printf(MSG_DEBUG, "MSNdis_StatusMediaDisconnect");
	ndis_events_send_event(events, EVENT_DISCONNECT, NULL, 0);
	}


	static void ndis_events_media_specific(struct ndis_events_data *events,
	IWbemClassObject *pObj)
	{
	VARIANT vt;
	HRESULT hr;
	LONG lower, upper, k;
	UCHAR ch;
	char data, pos;
	size_t data_len;

	wpa_printf(MSG_DEBUG, "MSNdis_StatusMediaSpecificIndication");

	/* This is the StatusBuffer from NdisMIndicateStatus() call */
	hr = IWbemClassObject_Get(pObj, L"NdisStatusMediaSpecificIndication",
	0, &vt, NULL, NULL);
	if (FAILED(hr)) {
	wpa_printf(MSG_DEBUG, "Could not get "
	"NdisStatusMediaSpecificIndication from "
	"the object?!");
	return;
	}

	SafeArrayGetLBound(V_ARRAY(&vt), 1, &lower);
	SafeArrayGetUBound(V_ARRAY(&vt), 1, &upper);
	data_len = upper - lower + 1;
	data = os_malloc(data_len);
	if (data == NULL) {
	wpa_printf(MSG_DEBUG, "Failed to allocate buffer for event "
	"data");
	VariantClear(&vt);
	return;
	}

	pos = data;
	for (k = lower; k <= upper; k++) {
	SafeArrayGetElement(V_ARRAY(&vt), &k, &ch);
	*pos++ = ch;
	}
	wpa_hexdump(MSG_DEBUG, "MediaSpecificEvent", (u8 *) data, data_len);

	VariantClear(&vt);

	ndis_events_send_event(events, EVENT_MEDIA_SPECIFIC, data, data_len);

	os_free(data);
	}


	static void ndis_events_adapter_arrival(struct ndis_events_data *events)
	{
	wpa_printf(MSG_DEBUG, "MSNdis_NotifyAdapterArrival");
	ndis_events_send_event(events, EVENT_ADAPTER_ARRIVAL, NULL, 0);
	}


	static void ndis_events_adapter_removal(struct ndis_events_data *events)
	{
	wpa_printf(MSG_DEBUG, "MSNdis_NotifyAdapterRemoval");
	ndis_events_send_event(events, EVENT_ADAPTER_REMOVAL, NULL, 0);
	}


	static HRESULT STDMETHODCALLTYPE
	ndis_events_indicate(IWbemObjectSink *this, long lObjectCount,
	IWbemClassObject __RPC_FAR __RPC_FAR ppObjArray)
	{
	struct ndis_events_data events = (struct ndis_events_data ) this;
	long i;

	if (events->terminating) {
	wpa_printf(MSG_DEBUG, "ndis_events_indicate: Ignore "
	"indication - terminating");
	return WBEM_NO_ERROR;
	}
	/* wpa_printf(MSG_DEBUG, "Notification received - %d object(s)",
	lObjectCount); */

	for (i = 0; i < lObjectCount; i++) {
	IWbemClassObject *pObj = ppObjArray[i];
	HRESULT hr;
	VARIANT vtClass, vt;

	hr = IWbemClassObject_Get(pObj, L"__CLASS", 0, &vtClass, NULL,
	NULL);
	if (FAILED(hr)) {
	wpa_printf(MSG_DEBUG, "Failed to get __CLASS from "
	"event.");
	break;
	}
	/* wpa_printf(MSG_DEBUG, "CLASS: '%S'", vtClass.bstrVal); */

	hr = IWbemClassObject_Get(pObj, L"InstanceName", 0, &vt, NULL,
	NULL);
	if (FAILED(hr)) {
	wpa_printf(MSG_DEBUG, "Failed to get InstanceName "
	"from event.");
	VariantClear(&vtClass);
	break;
	}

	if (wcscmp(vtClass.bstrVal,
	L"MSNdis_NotifyAdapterArrival") == 0) {
	wpa_printf(MSG_DEBUG, "ndis_events_indicate: Try to "
	"update adapter description since it may "
	"have changed with new adapter instance");
	ndis_events_get_adapter(events, events->ifname, NULL);
	}

	if (wcscmp(events->adapter_desc, vt.bstrVal) != 0) {
	wpa_printf(MSG_DEBUG, "ndis_events_indicate: Ignore "
	"indication for foreign adapter: "
	"InstanceName: '%S' __CLASS: '%S'",
	vt.bstrVal, vtClass.bstrVal);
	VariantClear(&vtClass);
	VariantClear(&vt);
	continue;
	}
	VariantClear(&vt);

	if (wcscmp(vtClass.bstrVal,
	L"MSNdis_StatusMediaSpecificIndication") == 0) {
	ndis_events_media_specific(events, pObj);
	} else if (wcscmp(vtClass.bstrVal,
	L"MSNdis_StatusMediaConnect") == 0) {
	ndis_events_media_connect(events);
	} else if (wcscmp(vtClass.bstrVal,
	L"MSNdis_StatusMediaDisconnect") == 0) {
	ndis_events_media_disconnect(events);
	} else if (wcscmp(vtClass.bstrVal,
	L"MSNdis_NotifyAdapterArrival") == 0) {
	ndis_events_adapter_arrival(events);
	} else if (wcscmp(vtClass.bstrVal,
	L"MSNdis_NotifyAdapterRemoval") == 0) {
	ndis_events_adapter_removal(events);
	} else {
	wpa_printf(MSG_DEBUG, "Unepected event - __CLASS: "
	"'%S'", vtClass.bstrVal);
	}

	VariantClear(&vtClass);
	}

	return WBEM_NO_ERROR;
	}


	static HRESULT STDMETHODCALLTYPE
	ndis_events_set_status(IWbemObjectSink *this, long lFlags, HRESULT hResult,
	BSTR strParam, IWbemClassObject __RPC_FAR *pObjParam)
	{
	return WBEM_NO_ERROR;
	}


	static int notification_query(IWbemObjectSink *pDestSink,
	IWbemServices pSvc, const char class_name)
	{
	HRESULT hr;
	WCHAR query[256];

	_snwprintf(query, 256,
	L"SELECT * FROM %S", class_name);
	wpa_printf(MSG_DEBUG, "ndis_events: WMI: %S", query);
	hr = call_IWbemServices_ExecNotificationQueryAsync(
	pSvc, L"WQL", query, 0, 0, pDestSink);
	if (FAILED(hr)) {
	wpa_printf(MSG_DEBUG, "ExecNotificationQueryAsync for %s "
	"failed with hresult of 0x%x",
	class_name, (int) hr);
	return -1;
	}

	return 0;
	}


	static int register_async_notification(IWbemObjectSink *pDestSink,
	IWbemServices *pSvc)
	{
	int i;
	const char *class_list[] = {
	"MSNdis_StatusMediaConnect",
	"MSNdis_StatusMediaDisconnect",
	"MSNdis_StatusMediaSpecificIndication",
	"MSNdis_NotifyAdapterArrival",
	"MSNdis_NotifyAdapterRemoval",
	NULL
	};

	for (i = 0; class_list[i]; i++) {
	if (notification_query(pDestSink, pSvc, class_list[i]) < 0)
	return -1;
	}

	return 0;
	}


	void ndis_events_deinit(struct ndis_events_data *events)
	{
	events->terminating = 1;
	IWbemServices_CancelAsyncCall(events->pSvc, &events->sink);
	IWbemObjectSink_Release(&events->sink);
	/*
	* Rest of deinitialization is done in ndis_events_destructor() once
	* all reference count drops to zero.
	*/
	}


	static int ndis_events_use_desc(struct ndis_events_data *events,
	const char *desc)
	{
	char tmp, pos;
	size_t len;

	if (desc == NULL) {
	if (events->adapter_desc == NULL)
	return -1;
	/* Continue using old description */
	return 0;
	}

	tmp = os_strdup(desc);
	if (tmp == NULL)
	return -1;

	pos = os_strstr(tmp, " (Microsoft's Packet Scheduler)");
	if (pos)
	*pos = '\0';

	len = os_strlen(tmp);
	events->adapter_desc = os_malloc((len + 1) * sizeof(WCHAR));
	if (events->adapter_desc == NULL) {
	os_free(tmp);
	return -1;
	}
	_snwprintf(events->adapter_desc, len + 1, L"%S", tmp);
	os_free(tmp);
	return 0;
	}


	static int ndis_events_get_adapter(struct ndis_events_data *events,
	const char ifname, const char desc)
	{
	HRESULT hr;
	IWbemServices *pSvc;
	#define MAX_QUERY_LEN 256
	WCHAR query[MAX_QUERY_LEN];
	IEnumWbemClassObject *pEnumerator;
	IWbemClassObject *pObj;
	ULONG uReturned;
	VARIANT vt;
	int len, pos;

	/*
	* Try to get adapter descriptor through WMI CIMv2 Win32_NetworkAdapter
	* to have better probability of matching with InstanceName from
	* MSNdis events. If this fails, use the provided description.
	*/

	os_free(events->adapter_desc);
	events->adapter_desc = NULL;

	hr = call_IWbemLocator_ConnectServer(
	events->pLoc, L"ROOT\\CIMV2", NULL, NULL, 0, 0, 0, 0, &pSvc);
	if (FAILED(hr)) {
	wpa_printf(MSG_ERROR, "ndis_events: Could not connect to WMI "
	"server (ROOT\\CIMV2) - error 0x%x", (int) hr);
	return ndis_events_use_desc(events, desc);
	}
	wpa_printf(MSG_DEBUG, "ndis_events: Connected to ROOT\\CIMV2.");

	_snwprintf(query, MAX_QUERY_LEN,
	L"SELECT Index FROM Win32_NetworkAdapterConfiguration "
	L"WHERE SettingID='%S'", ifname);
	wpa_printf(MSG_DEBUG, "ndis_events: WMI: %S", query);

	hr = call_IWbemServices_ExecQuery(
	pSvc, L"WQL", query,
	WBEM_FLAG_FORWARD_ONLY \| WBEM_FLAG_RETURN_IMMEDIATELY,
	NULL, &pEnumerator);
	if (!SUCCEEDED(hr)) {
	wpa_printf(MSG_DEBUG, "ndis_events: Failed to query interface "
	"GUID from Win32_NetworkAdapterConfiguration: "
	"0x%x", (int) hr);
	IWbemServices_Release(pSvc);
	return ndis_events_use_desc(events, desc);
	}

	uReturned = 0;
	hr = IEnumWbemClassObject_Next(pEnumerator, WBEM_INFINITE, 1,
	&pObj, &uReturned);
	if (!SUCCEEDED(hr) \|\| uReturned == 0) {
	wpa_printf(MSG_DEBUG, "ndis_events: Failed to find interface "
	"GUID from Win32_NetworkAdapterConfiguration: "
	"0x%x", (int) hr);
	IEnumWbemClassObject_Release(pEnumerator);
	IWbemServices_Release(pSvc);
	return ndis_events_use_desc(events, desc);
	}
	IEnumWbemClassObject_Release(pEnumerator);

	VariantInit(&vt);
	hr = IWbemClassObject_Get(pObj, L"Index", 0, &vt, NULL, NULL);
	if (!SUCCEEDED(hr)) {
	wpa_printf(MSG_DEBUG, "ndis_events: Failed to get Index from "
	"Win32_NetworkAdapterConfiguration: 0x%x",
	(int) hr);
	IWbemServices_Release(pSvc);
	return ndis_events_use_desc(events, desc);
	}

	_snwprintf(query, MAX_QUERY_LEN,
	L"SELECT Name,PNPDeviceID FROM Win32_NetworkAdapter WHERE "
	L"Index=%d",
	vt.uintVal);
	wpa_printf(MSG_DEBUG, "ndis_events: WMI: %S", query);
	VariantClear(&vt);
	IWbemClassObject_Release(pObj);

	hr = call_IWbemServices_ExecQuery(
	pSvc, L"WQL", query,
	WBEM_FLAG_FORWARD_ONLY \| WBEM_FLAG_RETURN_IMMEDIATELY,
	NULL, &pEnumerator);
	if (!SUCCEEDED(hr)) {
	wpa_printf(MSG_DEBUG, "ndis_events: Failed to query interface "
	"from Win32_NetworkAdapter: 0x%x", (int) hr);
	IWbemServices_Release(pSvc);
	return ndis_events_use_desc(events, desc);
	}

	uReturned = 0;
	hr = IEnumWbemClassObject_Next(pEnumerator, WBEM_INFINITE, 1,
	&pObj, &uReturned);
	if (!SUCCEEDED(hr) \|\| uReturned == 0) {
	wpa_printf(MSG_DEBUG, "ndis_events: Failed to find interface "
	"from Win32_NetworkAdapter: 0x%x", (int) hr);
	IEnumWbemClassObject_Release(pEnumerator);
	IWbemServices_Release(pSvc);
	return ndis_events_use_desc(events, desc);
	}
	IEnumWbemClassObject_Release(pEnumerator);

	hr = IWbemClassObject_Get(pObj, L"Name", 0, &vt, NULL, NULL);
	if (!SUCCEEDED(hr)) {
	wpa_printf(MSG_DEBUG, "ndis_events: Failed to get Name from "
	"Win32_NetworkAdapter: 0x%x", (int) hr);
	IWbemClassObject_Release(pObj);
	IWbemServices_Release(pSvc);
	return ndis_events_use_desc(events, desc);
	}

	wpa_printf(MSG_DEBUG, "ndis_events: Win32_NetworkAdapter::Name='%S'",
	vt.bstrVal);
	events->adapter_desc = _wcsdup(vt.bstrVal);
	VariantClear(&vt);

	/*
	* Try to get even better candidate for matching with InstanceName
	* from Win32_PnPEntity. This is needed at least for some USB cards
	* that can change the InstanceName whenever being unplugged and
	* plugged again.
	*/

	hr = IWbemClassObject_Get(pObj, L"PNPDeviceID", 0, &vt, NULL, NULL);
	if (!SUCCEEDED(hr)) {
	wpa_printf(MSG_DEBUG, "ndis_events: Failed to get PNPDeviceID "
	"from Win32_NetworkAdapter: 0x%x", (int) hr);
	IWbemClassObject_Release(pObj);
	IWbemServices_Release(pSvc);
	if (events->adapter_desc == NULL)
	return ndis_events_use_desc(events, desc);
	return 0; /* use Win32_NetworkAdapter::Name */
	}

	wpa_printf(MSG_DEBUG, "ndis_events: Win32_NetworkAdapter::PNPDeviceID="
	"'%S'", vt.bstrVal);

	len = _snwprintf(query, MAX_QUERY_LEN,
	L"SELECT Name FROM Win32_PnPEntity WHERE DeviceID='");
	if (len < 0 \|\| len >= MAX_QUERY_LEN - 1) {
	VariantClear(&vt);
	IWbemClassObject_Release(pObj);
	IWbemServices_Release(pSvc);
	if (events->adapter_desc == NULL)
	return ndis_events_use_desc(events, desc);
	return 0; /* use Win32_NetworkAdapter::Name */
	}

	/* Escape \ as \\ */
	for (pos = 0; vt.bstrVal[pos] && len < MAX_QUERY_LEN - 2; pos++) {
	if (vt.bstrVal[pos] == '\\') {
	if (len >= MAX_QUERY_LEN - 3)
	break;
	query[len++] = '\\';
	}
	query[len++] = vt.bstrVal[pos];
	}
	query[len++] = L'\'';
	query[len] = L'\0';
	VariantClear(&vt);
	IWbemClassObject_Release(pObj);
	wpa_printf(MSG_DEBUG, "ndis_events: WMI: %S", query);

	hr = call_IWbemServices_ExecQuery(
	pSvc, L"WQL", query,
	WBEM_FLAG_FORWARD_ONLY \| WBEM_FLAG_RETURN_IMMEDIATELY,
	NULL, &pEnumerator);
	if (!SUCCEEDED(hr)) {
	wpa_printf(MSG_DEBUG, "ndis_events: Failed to query interface "
	"Name from Win32_PnPEntity: 0x%x", (int) hr);
	IWbemServices_Release(pSvc);
	if (events->adapter_desc == NULL)
	return ndis_events_use_desc(events, desc);
	return 0; /* use Win32_NetworkAdapter::Name */
	}

	uReturned = 0;
	hr = IEnumWbemClassObject_Next(pEnumerator, WBEM_INFINITE, 1,
	&pObj, &uReturned);
	if (!SUCCEEDED(hr) \|\| uReturned == 0) {
	wpa_printf(MSG_DEBUG, "ndis_events: Failed to find interface "
	"from Win32_PnPEntity: 0x%x", (int) hr);
	IEnumWbemClassObject_Release(pEnumerator);
	IWbemServices_Release(pSvc);
	if (events->adapter_desc == NULL)
	return ndis_events_use_desc(events, desc);
	return 0; /* use Win32_NetworkAdapter::Name */
	}
	IEnumWbemClassObject_Release(pEnumerator);

	hr = IWbemClassObject_Get(pObj, L"Name", 0, &vt, NULL, NULL);
	if (!SUCCEEDED(hr)) {
	wpa_printf(MSG_DEBUG, "ndis_events: Failed to get Name from "
	"Win32_PnPEntity: 0x%x", (int) hr);
	IWbemClassObject_Release(pObj);
	IWbemServices_Release(pSvc);
	if (events->adapter_desc == NULL)
	return ndis_events_use_desc(events, desc);
	return 0; /* use Win32_NetworkAdapter::Name */
	}

	wpa_printf(MSG_DEBUG, "ndis_events: Win32_PnPEntity::Name='%S'",
	vt.bstrVal);
	os_free(events->adapter_desc);
	events->adapter_desc = _wcsdup(vt.bstrVal);
	VariantClear(&vt);

	IWbemClassObject_Release(pObj);

	IWbemServices_Release(pSvc);

	if (events->adapter_desc == NULL)
	return ndis_events_use_desc(events, desc);

	return 0;
	}


	struct ndis_events_data *
	ndis_events_init(HANDLE read_pipe, HANDLE event_avail,
	const char ifname, const char desc)
	{
	HRESULT hr;
	IWbemObjectSink *pSink;
	struct ndis_events_data *events;

	events = os_zalloc(sizeof(*events));
	if (events == NULL) {
	wpa_printf(MSG_ERROR, "Could not allocate sink for events.");
	return NULL;
	}
	events->ifname = os_strdup(ifname);
	if (events->ifname == NULL) {
	os_free(events);
	return NULL;
	}

	if (wmi_refcnt++ == 0) {
	hr = CoInitializeEx(0, COINIT_MULTITHREADED);
	if (FAILED(hr)) {
	wpa_printf(MSG_ERROR, "CoInitializeEx() failed - "
	"returned 0x%x", (int) hr);
	os_free(events);
	return NULL;
	}
	}

	if (wmi_first) {
	/* CoInitializeSecurity() must be called once and only once
	* per process, so let's use wmi_first flag to protect against
	* multiple calls. */
	wmi_first = 0;

	hr = CoInitializeSecurity(NULL, -1, NULL, NULL,
	RPC_C_AUTHN_LEVEL_PKT_PRIVACY,
	RPC_C_IMP_LEVEL_IMPERSONATE,
	NULL, EOAC_SECURE_REFS, NULL);
	if (FAILED(hr)) {
	wpa_printf(MSG_ERROR, "CoInitializeSecurity() failed "
	"- returned 0x%x", (int) hr);
	os_free(events);
	return NULL;
	}
	}

	hr = CoCreateInstance(&CLSID_WbemLocator, 0, CLSCTX_INPROC_SERVER,
	&IID_IWbemLocator,
	(LPVOID ) (void ) &events->pLoc);
	if (FAILED(hr)) {
	wpa_printf(MSG_ERROR, "CoCreateInstance() failed - returned "
	"0x%x", (int) hr);
	CoUninitialize();
	os_free(events);
	return NULL;
	}

	if (ndis_events_get_adapter(events, ifname, desc) < 0) {
	CoUninitialize();
	os_free(events);
	return NULL;
	}
	wpa_printf(MSG_DEBUG, "ndis_events: use adapter descriptor '%S'",
	events->adapter_desc);

	hr = call_IWbemLocator_ConnectServer(
	events->pLoc, L"ROOT\\WMI", NULL, NULL,
	0, 0, 0, 0, &events->pSvc);
	if (FAILED(hr)) {
	wpa_printf(MSG_ERROR, "Could not connect to server - error "
	"0x%x", (int) hr);
	CoUninitialize();
	os_free(events->adapter_desc);
	os_free(events);
	return NULL;
	}
	wpa_printf(MSG_DEBUG, "Connected to ROOT\\WMI.");

	ndis_events_constructor(events);
	pSink = &events->sink;
	pSink->lpVtbl = &events->sink_vtbl;
	events->sink_vtbl.QueryInterface = ndis_events_query_interface;
	events->sink_vtbl.AddRef = ndis_events_add_ref;
	events->sink_vtbl.Release = ndis_events_release;
	events->sink_vtbl.Indicate = ndis_events_indicate;
	events->sink_vtbl.SetStatus = ndis_events_set_status;

	if (register_async_notification(pSink, events->pSvc) < 0) {
	wpa_printf(MSG_DEBUG, "Failed to register async "
	"notifications");
	ndis_events_destructor(events);
	os_free(events->adapter_desc);
	os_free(events);
	return NULL;
	}

	*read_pipe = events->read_pipe;
	*event_avail = events->event_avail;

	return events;
	}