chrome/browser/metrics/cloned_install_detector.h

   1 // Copyright 2014 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 CHROME_BROWSER_METRICS_CLONED_INSTALL_DETECTOR_H_
   6 #define CHROME_BROWSER_METRICS_CLONED_INSTALL_DETECTOR_H_
   7
   8 #include "base/gtest_prod_util.h"
   9 #include "base/memory/ref_counted.h"
  10 #include "base/memory/weak_ptr.h"
  11
  12 class PrefRegistrySimple;
  13 class PrefService;
  14
  15 namespace metrics {
  16
  17 class MachineIdProvider;
  18
  19 // A class for detecting if an install is cloned. It does this by detecting
  20 // when the hardware running Chrome changes.
  21 class ClonedInstallDetector {
  22  public:
  23   explicit ClonedInstallDetector(MachineIdProvider* raw_id_provider);
  24   virtual ~ClonedInstallDetector();
  25
  26   // Posts a task to generate a machine ID and store it to a local state pref.
  27   // If the newly generated ID is different than the previously stored one, then
  28   // the install is considered cloned. The ID is a 24-bit value based off of
  29   // machine characteristics. This value should never be sent over the network.
  30   // TODO(jwd): Implement change detection.
  31   void CheckForClonedInstall(PrefService* local_state);
  32
  33   static void RegisterPrefs(PrefRegistrySimple* registry);
  34
  35  private:
  36   FRIEND_TEST_ALL_PREFIXES(ClonedInstallDetectorTest, SaveId);
  37   FRIEND_TEST_ALL_PREFIXES(ClonedInstallDetectorTest, DetectClone);
  38
  39   // Converts raw_id into a 24-bit hash and stores the hash in |local_state|.
  40   // |raw_id| is not a const ref because it's passed from a cross-thread post
  41   // task.
  42   void SaveMachineId(PrefService* local_state, std::string raw_id);
  43
  44   scoped_refptr<MachineIdProvider> raw_id_provider_;
  45   base::WeakPtrFactory<ClonedInstallDetector> weak_ptr_factory_;
  46
  47   DISALLOW_COPY_AND_ASSIGN(ClonedInstallDetector);
  48 };
  49
  50 }  // namespace metrics
  51
  52 #endif  // CHROME_BROWSER_METRICS_CLONED_INSTALL_DETECTOR_H_