1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
|
// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef CHROME_BROWSER_CHROMEOS_SYSTEM_DEVICE_DISABLING_MANAGER_H_
#define CHROME_BROWSER_CHROMEOS_SYSTEM_DEVICE_DISABLING_MANAGER_H_
#include <string>
#include "base/callback.h"
#include "base/macros.h"
#include "base/memory/scoped_ptr.h"
#include "base/memory/weak_ptr.h"
#include "base/observer_list.h"
#include "chrome/browser/chromeos/settings/cros_settings.h"
namespace policy {
class BrowserPolicyConnectorChromeOS;
}
namespace user_manager {
class UserManager;
}
namespace chromeos {
namespace system {
// If an enrolled device is lost or stolen, it can be remotely disabled by its
// owner. The disabling is triggered in two different ways, depending on the
// state the device is in:
// - If the device has been wiped, it will perform a hash dance during OOBE to
// find out whether any persistent state has been stored for it on the server.
// If so, persistent state is retrieved as a |DeviceStateRetrievalResponse|
// protobuf, parsed and written to the |prefs::kServerBackedDeviceState| local
// state pref. At the appropriate place in the OOBE flow, the
// |WizardController| will call CheckWhetherDeviceDisabledDuringOOBE() to find
// out whether the device is disabled, causing it to either show or skip the
// device disabled screen.
// - If the device has not been wiped, the disabled state is retrieved with
// every device policy fetch as part of the |PolicyData| protobuf, parsed and
// written to the |chromeos::kDeviceDisabled| cros setting. This class
// monitors the cros setting. When the device becomes disabled, one of two
// actions is taken:
// 1) If no session is in progress, the device disabled screen is shown
// immediately.
// 2) If a session is in progress, the session is terminated. After Chrome has
// restarted on the login screen, the disabled screen is shown per 1).
// This ensures that when a device is disabled, there is never any user
// session running in the backround.
// When the device is re-enabled, Chrome is restarted once more to resume the
// regular login screen flows from a known-good point.
class DeviceDisablingManager {
public:
using DeviceDisabledCheckCallback = base::Callback<void(bool)>;
class Observer {
public:
virtual ~Observer();
virtual void OnDisabledMessageChanged(
const std::string& disabled_message) = 0;
private:
DISALLOW_ASSIGN(Observer);
};
class Delegate {
public:
virtual ~Delegate();
// Terminate the current session (if any) and restart Chrome to show the
// login screen.
virtual void RestartToLoginScreen() = 0;
// Show the device disabled screen.
virtual void ShowDeviceDisabledScreen() = 0;
private:
DISALLOW_ASSIGN(Delegate);
};
// |delegate| must outlive |this|.
DeviceDisablingManager(Delegate* delegate,
CrosSettings* cros_settings,
user_manager::UserManager* user_manager);
~DeviceDisablingManager();
void AddObserver(Observer* observer);
void RemoveObserver(Observer* observer);
// Returns the cached domain that owns the device. The domain is only
// guaranteed to be up to date if the disabled screen was triggered.
const std::string& enrollment_domain() const { return enrollment_domain_; }
// Returns the cached disabled message. The message is only guaranteed to be
// up to date if the disabled screen was triggered.
const std::string& disabled_message() const { return disabled_message_; }
// Performs a check whether the device is disabled during OOBE. |callback|
// will be invoked with the result of the check.
void CheckWhetherDeviceDisabledDuringOOBE(
const DeviceDisabledCheckCallback& callback);
// Whenever trusted cros settings indicate that the device is disabled, this
// method should be used to check whether the device disabling is to be
// honored. If this method returns false, the device should not be disabled.
static bool HonorDeviceDisablingDuringNormalOperation();
private:
void Init();
// Cache the disabled message and inform observers if it changed.
void CacheDisabledMessageAndNotify(const std::string& disabled_message);
void UpdateFromCrosSettings();
Delegate* delegate_;
policy::BrowserPolicyConnectorChromeOS* browser_policy_connector_;
CrosSettings* cros_settings_;
user_manager::UserManager* user_manager_;
base::ObserverList<Observer> observers_;
scoped_ptr<CrosSettings::ObserverSubscription> device_disabled_subscription_;
scoped_ptr<CrosSettings::ObserverSubscription> disabled_message_subscription_;
// Indicates whether the device was disabled when the cros settings were last
// read.
bool device_disabled_;
// A cached copy of the domain that owns the device.
std::string enrollment_domain_;
// A cached copy of the message to show on the device disabled screen.
std::string disabled_message_;
base::WeakPtrFactory<DeviceDisablingManager> weak_factory_;
DISALLOW_COPY_AND_ASSIGN(DeviceDisablingManager);
};
} // namespace system
} // namespace chromeos
#endif // CHROME_BROWSER_CHROMEOS_SYSTEM_DEVICE_DISABLING_MANAGER_H_
|