1 /*
2  * Copyright (C) 2008 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package com.android.settings;
18 
19 import android.app.Activity;
20 import android.app.AlertDialog;
21 import android.app.admin.DevicePolicyManager;
22 import android.content.BroadcastReceiver;
23 import android.content.Context;
24 import android.content.Intent;
25 import android.content.IntentFilter;
26 import android.content.res.Resources;
27 import android.os.BatteryManager;
28 import android.os.Bundle;
29 import android.os.UserHandle;
30 import android.os.storage.StorageManager;
31 import android.support.v7.preference.Preference;
32 import android.text.TextUtils;
33 import android.view.LayoutInflater;
34 import android.view.View;
35 import android.view.ViewGroup;
36 import android.widget.Button;
37 
38 import com.android.internal.logging.nano.MetricsProto.MetricsEvent;
39 import com.android.settings.core.InstrumentedPreferenceFragment;
40 
41 public class CryptKeeperSettings extends InstrumentedPreferenceFragment {
42     private static final String TAG = "CryptKeeper";
43     private static final String TYPE = "type";
44     private static final String PASSWORD = "password";
45 
46     private static final int KEYGUARD_REQUEST = 55;
47 
48     // Minimum battery charge level (in percent) to launch encryption.  If the battery charge is
49     // lower than this, encryption should not be activated.
50     private static final int MIN_BATTERY_LEVEL = 80;
51 
52     private View mContentView;
53     private Button mInitiateButton;
54     private View mPowerWarning;
55     private View mBatteryWarning;
56     private IntentFilter mIntentFilter;
57 
58     private BroadcastReceiver mIntentReceiver = new BroadcastReceiver() {
59         @Override
60         public void onReceive(Context context, Intent intent) {
61             String action = intent.getAction();
62             if (action.equals(Intent.ACTION_BATTERY_CHANGED)) {
63                 final int level = intent.getIntExtra(BatteryManager.EXTRA_LEVEL, 0);
64                 final int plugged = intent.getIntExtra(BatteryManager.EXTRA_PLUGGED, 0);
65                 final int invalidCharger = intent.getIntExtra(
66                     BatteryManager.EXTRA_INVALID_CHARGER, 0);
67 
68                 final boolean levelOk = level >= MIN_BATTERY_LEVEL;
69                 final boolean pluggedOk =
70                     ((plugged & BatteryManager.BATTERY_PLUGGED_ANY) != 0) &&
71                      invalidCharger == 0;
72 
73                 // Update UI elements based on power/battery status
74                 mInitiateButton.setEnabled(levelOk && pluggedOk);
75                 mPowerWarning.setVisibility(pluggedOk ? View.GONE : View.VISIBLE );
76                 mBatteryWarning.setVisibility(levelOk ? View.GONE : View.VISIBLE);
77             }
78         }
79     };
80 
81     /**
82      * If the user clicks to begin the reset sequence, we next require a
83      * keyguard confirmation if the user has currently enabled one.  If there
84      * is no keyguard available, we prompt the user to set a password.
85      */
86     private Button.OnClickListener mInitiateListener = new Button.OnClickListener() {
87         @Override
88         public void onClick(View v) {
89             if (!runKeyguardConfirmation(KEYGUARD_REQUEST)) {
90                 // TODO replace (or follow) this dialog with an explicit launch into password UI
91                 new AlertDialog.Builder(getActivity())
92                     .setTitle(R.string.crypt_keeper_dialog_need_password_title)
93                     .setMessage(R.string.crypt_keeper_dialog_need_password_message)
94                     .setPositiveButton(android.R.string.ok, null)
95                     .create()
96                     .show();
97             }
98         }
99     };
100 
101     @Override
onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedState)102     public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedState) {
103         mContentView = inflater.inflate(R.layout.crypt_keeper_settings, null);
104 
105         mIntentFilter = new IntentFilter();
106         mIntentFilter.addAction(Intent.ACTION_BATTERY_CHANGED);
107 
108         mInitiateButton = (Button) mContentView.findViewById(R.id.initiate_encrypt);
109         mInitiateButton.setOnClickListener(mInitiateListener);
110         mInitiateButton.setEnabled(false);
111 
112         mPowerWarning = mContentView.findViewById(R.id.warning_unplugged);
113         mBatteryWarning = mContentView.findViewById(R.id.warning_low_charge);
114 
115         return mContentView;
116     }
117 
118     @Override
getMetricsCategory()119     public int getMetricsCategory() {
120         return MetricsEvent.CRYPT_KEEPER;
121     }
122 
123     @Override
onResume()124     public void onResume() {
125         super.onResume();
126         getActivity().registerReceiver(mIntentReceiver, mIntentFilter);
127     }
128 
129     @Override
onPause()130     public void onPause() {
131         super.onPause();
132         getActivity().unregisterReceiver(mIntentReceiver);
133     }
134 
135     /**
136      * If encryption is already started, and this launched via a "start encryption" intent,
137      * then exit immediately - it's already up and running, so there's no point in "starting" it.
138      */
139     @Override
onActivityCreated(Bundle savedInstanceState)140     public void onActivityCreated(Bundle savedInstanceState) {
141         super.onActivityCreated(savedInstanceState);
142         Activity activity = getActivity();
143         Intent intent = activity.getIntent();
144         if (DevicePolicyManager.ACTION_START_ENCRYPTION.equals(intent.getAction())) {
145             DevicePolicyManager dpm = (DevicePolicyManager)
146                     activity.getSystemService(Context.DEVICE_POLICY_SERVICE);
147             if (dpm != null) {
148                 int status = dpm.getStorageEncryptionStatus();
149                 if (status != DevicePolicyManager.ENCRYPTION_STATUS_INACTIVE) {
150                     // There is nothing to do here, so simply finish() (which returns to caller)
151                     activity.finish();
152                 }
153             }
154         }
155     }
156 
157     /**
158      * Keyguard validation is run using the standard {@link ConfirmLockPattern}
159      * component as a subactivity
160      * @param request the request code to be returned once confirmation finishes
161      * @return true if confirmation launched
162      */
runKeyguardConfirmation(int request)163     private boolean runKeyguardConfirmation(int request) {
164         Resources res = getActivity().getResources();
165         ChooseLockSettingsHelper helper = new ChooseLockSettingsHelper(getActivity(), this);
166 
167         if (helper.utils().getKeyguardStoredPasswordQuality(UserHandle.myUserId())
168                 == DevicePolicyManager.PASSWORD_QUALITY_UNSPECIFIED) {
169             showFinalConfirmation(StorageManager.CRYPT_TYPE_DEFAULT, "");
170             return true;
171         }
172 
173         return helper.launchConfirmationActivity(request,
174                 res.getText(R.string.crypt_keeper_encrypt_title), true);
175     }
176 
177     @Override
onActivityResult(int requestCode, int resultCode, Intent data)178     public void onActivityResult(int requestCode, int resultCode, Intent data) {
179         super.onActivityResult(requestCode, resultCode, data);
180 
181         if (requestCode != KEYGUARD_REQUEST) {
182             return;
183         }
184 
185         // If the user entered a valid keyguard trace, present the final
186         // confirmation prompt; otherwise, go back to the initial state.
187         if (resultCode == Activity.RESULT_OK && data != null) {
188             int type = data.getIntExtra(ChooseLockSettingsHelper.EXTRA_KEY_TYPE, -1);
189             String password = data.getStringExtra(ChooseLockSettingsHelper.EXTRA_KEY_PASSWORD);
190             if (!TextUtils.isEmpty(password)) {
191                 showFinalConfirmation(type, password);
192             }
193         }
194     }
195 
showFinalConfirmation(int type, String password)196     private void showFinalConfirmation(int type, String password) {
197         Preference preference = new Preference(getPreferenceManager().getContext());
198         preference.setFragment(CryptKeeperConfirm.class.getName());
199         preference.setTitle(R.string.crypt_keeper_confirm_title);
200         addEncryptionInfoToPreference(preference, type, password);
201         ((SettingsActivity) getActivity()).onPreferenceStartFragment(null, preference);
202     }
203 
addEncryptionInfoToPreference(Preference preference, int type, String password)204     private void addEncryptionInfoToPreference(Preference preference, int type, String password) {
205         Activity activity = getActivity();
206         DevicePolicyManager dpm = (DevicePolicyManager)
207                 activity.getSystemService(Context.DEVICE_POLICY_SERVICE);
208         if (dpm.getDoNotAskCredentialsOnBoot()) {
209             preference.getExtras().putInt(TYPE, StorageManager.CRYPT_TYPE_DEFAULT);
210             preference.getExtras().putString(PASSWORD, "");
211         } else {
212             preference.getExtras().putInt(TYPE, type);
213             preference.getExtras().putString(PASSWORD, password);
214         }
215     }
216 }
217