components/policy/core/common/policy_loader_win.h

   1 // Copyright (c) 2012 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 #ifndef COMPONENTS_POLICY_CORE_COMMON_POLICY_LOADER_WIN_H_
   6 #define COMPONENTS_POLICY_CORE_COMMON_POLICY_LOADER_WIN_H_
   7
   8 #include <windows.h>
   9 #include <userenv.h>
  10
  11 #include "base/basictypes.h"
  12 #include "base/files/file_path.h"
  13 #include "base/memory/ref_counted.h"
  14 #include "base/memory/scoped_ptr.h"
  15 #include "base/strings/string16.h"
  16 #include "base/synchronization/waitable_event.h"
  17 #include "base/win/object_watcher.h"
  18 #include "components/policy/core/common/async_policy_loader.h"
  19 #include "components/policy/core/common/policy_types.h"
  20 #include "components/policy/policy_export.h"
  21
  22 namespace base {
  23 class SequencedTaskRunner;
  24 }
  25
  26 namespace policy {
  27
  28 class AppliedGPOListProvider;
  29 class PolicyLoadStatusSample;
  30 class PolicyMap;
  31 class RegistryDict;
  32
  33 // Interface for mocking out GPO enumeration in tests.
  34 class POLICY_EXPORT AppliedGPOListProvider {
  35  public:
  36   virtual ~AppliedGPOListProvider() {}
  37   virtual DWORD GetAppliedGPOList(DWORD flags,
  38                                   LPCTSTR machine_name,
  39                                   PSID sid_user,
  40                                   GUID* extension_guid,
  41                                   PGROUP_POLICY_OBJECT* gpo_list) = 0;
  42   virtual BOOL FreeGPOList(PGROUP_POLICY_OBJECT gpo_list) = 0;
  43 };
  44
  45 // Loads policies from the Windows registry, and watches for Group Policy
  46 // notifications to trigger reloads.
  47 class POLICY_EXPORT PolicyLoaderWin
  48     : public AsyncPolicyLoader,
  49       public base::win::ObjectWatcher::Delegate {
  50  public:
  51   // The PReg file name used by GPO.
  52   static const base::FilePath::CharType kPRegFileName[];
  53
  54   // Passing |gpo_provider| equal nullptr forces all reads to go through the
  55   // registry.  This is undesirable for Chrome (see crbug.com/259236), but
  56   // needed for some other use cases (i.e. Chromoting - see crbug.com/460734).
  57   PolicyLoaderWin(scoped_refptr<base::SequencedTaskRunner> task_runner,
  58                   const base::string16& chrome_policy_key,
  59                   AppliedGPOListProvider* gpo_provider);
  60   ~PolicyLoaderWin() override;
  61
  62   // Creates a policy loader that uses the Win API to access GPO.
  63   static scoped_ptr<PolicyLoaderWin> Create(
  64       scoped_refptr<base::SequencedTaskRunner> task_runner,
  65       const base::string16& chrome_policy_key);
  66
  67   // AsyncPolicyLoader implementation.
  68   void InitOnBackgroundThread() override;
  69   scoped_ptr<PolicyBundle> Load() override;
  70
  71  private:
  72   // Reads Chrome Policy from a PReg file at the given path and stores the
  73   // result in |policy|.
  74   bool ReadPRegFile(const base::FilePath& preg_file,
  75                     RegistryDict* policy,
  76                     PolicyLoadStatusSample* status);
  77
  78   // Loads and parses GPO policy in |policy_object_list| for scope |scope|. If
  79   // successful, stores the result in |policy| and returns true. Returns false
  80   // on failure reading the policy, indicating that policy loading should fall
  81   // back to reading the registry.
  82   bool LoadGPOPolicy(PolicyScope scope,
  83                      PGROUP_POLICY_OBJECT policy_object_list,
  84                      RegistryDict* policy,
  85                      PolicyLoadStatusSample* status);
  86
  87   // Queries Windows for applied group policy and writes the result to |policy|.
  88   // This is the preferred way to obtain GPO data, there are reports of abuse
  89   // of the registry GPO keys by 3rd-party software.
  90   bool ReadPolicyFromGPO(PolicyScope scope,
  91                          RegistryDict* policy,
  92                          PolicyLoadStatusSample* status);
  93
  94   // Parses Chrome policy from |gpo_dict| for the given |scope| and |level| and
  95   // merges it into |chrome_policy_map|.
  96   void LoadChromePolicy(const RegistryDict* gpo_dict,
  97                         PolicyLevel level,
  98                         PolicyScope scope,
  99                         PolicyMap* chrome_policy_map);
 100
 101   // Loads 3rd-party policy from |gpo_dict| and merges it into |bundle|.
 102   void Load3rdPartyPolicy(const RegistryDict* gpo_dict,
 103                           PolicyScope scope,
 104                           PolicyBundle* bundle);
 105
 106   // Installs the watchers for the Group Policy update events.
 107   void SetupWatches();
 108
 109   // ObjectWatcher::Delegate overrides:
 110   void OnObjectSignaled(HANDLE object) override;
 111
 112   bool is_initialized_;
 113   const base::string16 chrome_policy_key_;
 114   class AppliedGPOListProvider* gpo_provider_;
 115
 116   base::WaitableEvent user_policy_changed_event_;
 117   base::WaitableEvent machine_policy_changed_event_;
 118   base::win::ObjectWatcher user_policy_watcher_;
 119   base::win::ObjectWatcher machine_policy_watcher_;
 120   bool user_policy_watcher_failed_;
 121   bool machine_policy_watcher_failed_;
 122
 123   DISALLOW_COPY_AND_ASSIGN(PolicyLoaderWin);
 124 };
 125
 126 }  // namespace policy
 127
 128 #endif  // COMPONENTS_POLICY_CORE_COMMON_POLICY_LOADER_WIN_H_