chrome/installer/util/wmi.cc

   1 // Copyright (c) 2010 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "chrome/installer/util/wmi.h"
   6
   7 #include <windows.h>
   8
   9 #include "base/basictypes.h"
  10 #include "base/win/scoped_bstr.h"
  11 #include "base/win/scoped_comptr.h"
  12 #include "base/win/scoped_variant.h"
  13
  14 #pragma comment(lib, "wbemuuid.lib")
  15
  16 using base::win::ScopedVariant;
  17
  18 namespace installer {
  19
  20 bool WMI::CreateLocalConnection(bool set_blanket,
  21                                 IWbemServices** wmi_services) {
  22   base::win::ScopedComPtr<IWbemLocator> wmi_locator;
  23   HRESULT hr = wmi_locator.CreateInstance(CLSID_WbemLocator, NULL,
  24                                           CLSCTX_INPROC_SERVER);
  25   if (FAILED(hr))
  26     return false;
  27
  28   base::win::ScopedComPtr<IWbemServices> wmi_services_r;
  29   hr = wmi_locator->ConnectServer(base::win::ScopedBstr(L"ROOT\\CIMV2"),
  30                                   NULL, NULL, 0, NULL, 0, 0,
  31                                   wmi_services_r.Receive());
  32   if (FAILED(hr))
  33     return false;
  34
  35   if (set_blanket) {
  36     hr = ::CoSetProxyBlanket(wmi_services_r.get(), RPC_C_AUTHN_WINNT,
  37                              RPC_C_AUTHZ_NONE, NULL, RPC_C_AUTHN_LEVEL_CALL,
  38                              RPC_C_IMP_LEVEL_IMPERSONATE, NULL, EOAC_NONE);
  39     if (FAILED(hr))
  40       return false;
  41   }
  42
  43   *wmi_services = wmi_services_r.Detach();
  44   return true;
  45 }
  46
  47 bool WMI::CreateClassMethodObject(IWbemServices* wmi_services,
  48                                   const std::wstring& class_name,
  49                                   const std::wstring& method_name,
  50                                   IWbemClassObject** class_instance) {
  51   // We attempt to instantiate a COM object that represents a WMI object plus
  52   // a method rolled into one entity.
  53   base::win::ScopedBstr b_class_name(class_name.c_str());
  54   base::win::ScopedBstr b_method_name(method_name.c_str());
  55   base::win::ScopedComPtr<IWbemClassObject> class_object;
  56   HRESULT hr;
  57   hr = wmi_services->GetObject(b_class_name, 0, NULL,
  58                                class_object.Receive(), NULL);
  59   if (FAILED(hr))
  60     return false;
  61
  62   base::win::ScopedComPtr<IWbemClassObject> params_def;
  63   hr = class_object->GetMethod(b_method_name, 0, params_def.Receive(), NULL);
  64   if (FAILED(hr))
  65     return false;
  66
  67   if (NULL == params_def.get()) {
  68     // You hit this special case if the WMI class is not a CIM class. MSDN
  69     // sometimes tells you this. Welcome to WMI hell.
  70     return false;
  71   }
  72
  73   hr = params_def->SpawnInstance(0, class_instance);
  74   return(SUCCEEDED(hr));
  75 }
  76
  77 bool SetParameter(IWbemClassObject* class_method,
  78                   const std::wstring& parameter_name, VARIANT* parameter) {
  79   HRESULT hr = class_method->Put(parameter_name.c_str(), 0, parameter, 0);
  80   return SUCCEEDED(hr);
  81 }
  82
  83
  84 // The code in Launch() basically calls the Create Method of the Win32_Process
  85 // CIM class is documented here:
  86 // http://msdn2.microsoft.com/en-us/library/aa389388(VS.85).aspx
  87 // NOTE: The documentation for the Create method suggests that the ProcessId
  88 // parameter and return value are of type uint32, but when we call the method
  89 // the values in the returned out_params, are VT_I4, which is int32.
  90
  91 bool WMIProcess::Launch(const std::wstring& command_line, int* process_id) {
  92   base::win::ScopedComPtr<IWbemServices> wmi_local;
  93   if (!WMI::CreateLocalConnection(true, wmi_local.Receive()))
  94     return false;
  95
  96   const wchar_t class_name[] = L"Win32_Process";
  97   const wchar_t method_name[] = L"Create";
  98   base::win::ScopedComPtr<IWbemClassObject> process_create;
  99   if (!WMI::CreateClassMethodObject(wmi_local.get(), class_name, method_name,
 100                                     process_create.Receive()))
 101     return false;
 102
 103   ScopedVariant b_command_line(command_line.c_str());
 104
 105   if (!SetParameter(process_create.get(), L"CommandLine",
 106                     b_command_line.AsInput()))
 107     return false;
 108
 109   base::win::ScopedComPtr<IWbemClassObject> out_params;
 110   HRESULT hr = wmi_local->ExecMethod(
 111       base::win::ScopedBstr(class_name), base::win::ScopedBstr(method_name), 0,
 112       NULL, process_create.get(), out_params.Receive(), NULL);
 113   if (FAILED(hr))
 114     return false;
 115
 116   // We're only expecting int32 or uint32 values, so no need for ScopedVariant.
 117   VARIANT ret_value = {VT_EMPTY};
 118   hr = out_params->Get(L"ReturnValue", 0, &ret_value, NULL, 0);
 119   if (FAILED(hr) || 0 != V_I4(&ret_value))
 120     return false;
 121
 122   VARIANT pid = {VT_EMPTY};
 123   hr = out_params->Get(L"ProcessId", 0, &pid, NULL, 0);
 124   if (FAILED(hr) || 0 == V_I4(&pid))
 125     return false;
 126
 127   if (process_id)
 128     *process_id = V_I4(&pid);
 129
 130   return true;
 131 }
 132
 133 base::string16 WMIComputerSystem::GetModel() {
 134   base::win::ScopedComPtr<IWbemServices> services;
 135   if (!WMI::CreateLocalConnection(true, services.Receive()))
 136     return base::string16();
 137
 138   base::win::ScopedBstr query_language(L"WQL");
 139   base::win::ScopedBstr query(L"SELECT * FROM Win32_ComputerSystem");
 140   base::win::ScopedComPtr<IEnumWbemClassObject> enumerator;
 141   HRESULT hr = services->ExecQuery(
 142       query_language, query,
 143       WBEM_FLAG_FORWARD_ONLY | WBEM_FLAG_RETURN_IMMEDIATELY, NULL,
 144       enumerator.Receive());
 145   if (FAILED(hr) || !enumerator.get())
 146     return base::string16();
 147
 148   base::win::ScopedComPtr<IWbemClassObject> class_object;
 149   ULONG items_returned = 0;
 150   hr = enumerator->Next(WBEM_INFINITE, 1,  class_object.Receive(),
 151                         &items_returned);
 152   if (!items_returned)
 153     return base::string16();
 154
 155   base::win::ScopedVariant manufacturer;
 156   class_object->Get(L"Manufacturer", 0, manufacturer.Receive(), 0, 0);
 157   base::win::ScopedVariant model;
 158   class_object->Get(L"Model", 0, model.Receive(), 0, 0);
 159
 160   base::string16 model_string;
 161   if (manufacturer.type() == VT_BSTR) {
 162     model_string = V_BSTR(&manufacturer);
 163     if (model.type() == VT_BSTR)
 164       model_string += L" ";
 165   }
 166   if (model.type() == VT_BSTR)
 167     model_string += V_BSTR(&model);
 168
 169   return model_string;
 170 }
 171
 172 }  // namespace installer