WMI - MSPower_DeviceEnable demo

WMIPowerTest.c

#include "stdafx.h"
#include <atlbase.h>
#include <atlstr.h>
#include <stdio.h>
#include <wbemidl.h> // For WMI
#pragma comment(lib, "wbemuuid.lib") // Link to WMI library.


//  ref.
//  https://docs.microsoft.com/en-us/windows/win32/wmisdk/creating-a-wmi-application-using-c-

int main() {
	// Step 1. Initialize COM.
	HRESULT hr = ::CoInitializeEx(NULL, COINIT_MULTITHREADED);
	if (FAILED(hr)) {
		printf("Failed, called CoInitializeEx(), return:0x%X\r\n", hr);
		return -1;
	}

	//  NOTE:
	//  When using asynchronous WMI API's remotely in an environment where the "Local System" account
	//  has no network identity (such as non-Kerberos domains), the authentication level of
	//  RPC_C_AUTHN_LEVEL_NONE is needed. However, lowering the authentication level to
	//  RPC_C_AUTHN_LEVEL_NONE makes your application less secure. It is wise to
	//  use semi-synchronous API's for accessing WMI data and events instead of the asynchronous ones.
	hr = ::CoInitializeSecurity(NULL, -1, NULL, NULL,
	        RPC_C_AUTHN_LEVEL_DEFAULT, RPC_C_IMP_LEVEL_IMPERSONATE,
	        NULL, EOAC_NONE, NULL);
	if (FAILED(hr)) {
		printf("Failed, called CoInitializeSecurity(), return:0x%X\r\n", hr);
		goto CleanUp;
	}

	{
		// Step 2. Create a connection to a WMI namespace.
		CComPtr<IWbemLocator> pWbemLocator;
		hr = pWbemLocator.CoCreateInstance(CLSID_WbemLocator);
		if (FAILED(hr)) {
			printf("Failed, called CoCreateInstance(), return:0x%X\r\n", hr);
			goto CleanUp;
		}
		
		// connect to namespace root\wmi
		CComPtr<IWbemServices> pWbemServices;
		hr = pWbemLocator->ConnectServer(CComBSTR(L"root\\wmi"), NULL, NULL, 0, NULL, 0, NULL, &pWbemServices);
		if (FAILED(hr)) {
			printf("Failed, called ConnectServer(), return:0x%X\r\n", hr);
			goto CleanUp;
		}

		// Step 3. Set the security levels on the WMI connection.
		// setting proxy security
		CComPtr<IClientSecurity> pClientSecurity;
		hr = pWbemServices->QueryInterface(IID_IClientSecurity, (void **)&pClientSecurity);
		if (FAILED(hr)) {
			printf("Failed, called QueryInterface(IID_IClientSecurity), return:0x%X\r\n", hr);
			goto CleanUp;
		}

		hr = pClientSecurity->SetBlanket(pWbemServices,
		        RPC_C_AUTHN_WINNT,
		        RPC_C_AUTHZ_NONE,
		        NULL,
		        RPC_C_AUTHN_LEVEL_CALL,
		        RPC_C_IMP_LEVEL_IMPERSONATE,
		        NULL,
		        EOAC_NONE);

		// Step 4. Implement the purpose of your application.
		CComPtr<IEnumWbemClassObject> pEnum;
		hr = pWbemServices->ExecQuery(CComBSTR(L"WQL"),
		        CComBSTR(L"Select * FROM MSPower_DeviceEnable"),
		        WBEM_FLAG_FORWARD_ONLY | WBEM_FLAG_RETURN_IMMEDIATELY,
		        NULL,
		        &pEnum);

		do {
			CComPtr<IWbemClassObject> pObj;
			ULONG uReturned = 0;
			CStringW prefix = L"\"PCI\\\\VEN_8086&DEV_9D";
			hr = pEnum->Next(WBEM_INFINITE, 1, &pObj, &uReturned);
			if (hr == WBEM_S_NO_ERROR) {
				CComBSTR bstrObj;
				pObj->GetObjectText(0, &bstrObj);
				CStringW find(bstrObj);
				if (int n = find.Find(prefix) > 0) {
					CStringW i2cs[] = {
						L"\"PCI\\\\VEN_8086&DEV_9DC5",
						L"\"PCI\\\\VEN_8086&DEV_9DC6",
						L"\"PCI\\\\VEN_8086&DEV_9DE8",
						L"\"PCI\\\\VEN_8086&DEV_9DE9",
						L"\"PCI\\\\VEN_8086&DEV_9DEA",
						L"\"PCI\\\\VEN_8086&DEV_9DEB"
					};

					for each (CStringW dev in i2cs) {
						if (find.Find(dev, n - 1) > 0) {
							CComVariant vtProp;
							CComBSTR en(L"Enable");
							// only for debug
							// wprintf(L"%s\n\n", (LPWSTR)bstrObj);
							if (WBEM_S_NO_ERROR == pObj->Get(en, 0, &vtProp, NULL, NULL)) {
								if (vtProp.boolVal != VARIANT_FALSE) {
									vtProp.boolVal = VARIANT_FALSE;
									hr = pObj->Put(en, 0, &vtProp, CIM_BOOLEAN);
									// Update Instance
									// https://docs.microsoft.com/en-us/windows/win32/wmisdk/updating-an-entire-instance
									// need administrator permission if got WBEM_E_ACCESS_DENIED (0x80041003)
									hr = pWbemServices->PutInstance(pObj, WBEM_FLAG_UPDATE_ONLY, NULL, NULL);
								}
							}
						}
					}
				}
			}
			pObj = NULL;
		} while (hr == WBEM_S_NO_ERROR);

	}

// Step 5. Cleanup and shut down your application.
CleanUp:
	CoUninitialize();
	return 0;
}