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
17package com.android.settings;
18
19import com.android.internal.widget.LockPatternUtils;
20
21import android.app.Activity;
22import android.app.AlertDialog;
23import android.app.Fragment;
24import android.app.admin.DevicePolicyManager;
25import android.content.BroadcastReceiver;
26import android.content.Context;
27import android.content.Intent;
28import android.content.IntentFilter;
29import android.content.res.Resources;
30import android.os.BatteryManager;
31import android.os.Bundle;
32import android.os.storage.StorageManager;
33import android.preference.Preference;
34import android.text.TextUtils;
35import android.view.LayoutInflater;
36import android.view.View;
37import android.view.ViewGroup;
38import android.widget.Button;
39
40public class CryptKeeperSettings extends Fragment {
41    private static final String TAG = "CryptKeeper";
42
43    private static final int KEYGUARD_REQUEST = 55;
44
45    // Minimum battery charge level (in percent) to launch encryption.  If the battery charge is
46    // lower than this, encryption should not be activated.
47    private static final int MIN_BATTERY_LEVEL = 80;
48
49    private View mContentView;
50    private Button mInitiateButton;
51    private View mPowerWarning;
52    private View mBatteryWarning;
53    private IntentFilter mIntentFilter;
54
55    private BroadcastReceiver mIntentReceiver = new BroadcastReceiver() {
56        @Override
57        public void onReceive(Context context, Intent intent) {
58            String action = intent.getAction();
59            if (action.equals(Intent.ACTION_BATTERY_CHANGED)) {
60                final int level = intent.getIntExtra(BatteryManager.EXTRA_LEVEL, 0);
61                final int plugged = intent.getIntExtra(BatteryManager.EXTRA_PLUGGED, 0);
62                final int invalidCharger = intent.getIntExtra(
63                    BatteryManager.EXTRA_INVALID_CHARGER, 0);
64
65                final boolean levelOk = level >= MIN_BATTERY_LEVEL;
66                final boolean pluggedOk =
67                    ((plugged & BatteryManager.BATTERY_PLUGGED_ANY) != 0) &&
68                     invalidCharger == 0;
69
70                // Update UI elements based on power/battery status
71                mInitiateButton.setEnabled(levelOk && pluggedOk);
72                mPowerWarning.setVisibility(pluggedOk ? View.GONE : View.VISIBLE );
73                mBatteryWarning.setVisibility(levelOk ? View.GONE : View.VISIBLE);
74            }
75        }
76    };
77
78    /**
79     * If the user clicks to begin the reset sequence, we next require a
80     * keyguard confirmation if the user has currently enabled one.  If there
81     * is no keyguard available, we prompt the user to set a password.
82     */
83    private Button.OnClickListener mInitiateListener = new Button.OnClickListener() {
84
85        public void onClick(View v) {
86            if (!runKeyguardConfirmation(KEYGUARD_REQUEST)) {
87                // TODO replace (or follow) this dialog with an explicit launch into password UI
88                new AlertDialog.Builder(getActivity())
89                    .setTitle(R.string.crypt_keeper_dialog_need_password_title)
90                    .setMessage(R.string.crypt_keeper_dialog_need_password_message)
91                    .setPositiveButton(android.R.string.ok, null)
92                    .create()
93                    .show();
94            }
95        }
96    };
97
98    @Override
99    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedState) {
100        mContentView = inflater.inflate(R.layout.crypt_keeper_settings, null);
101
102        mIntentFilter = new IntentFilter();
103        mIntentFilter.addAction(Intent.ACTION_BATTERY_CHANGED);
104
105        mInitiateButton = (Button) mContentView.findViewById(R.id.initiate_encrypt);
106        mInitiateButton.setOnClickListener(mInitiateListener);
107        mInitiateButton.setEnabled(false);
108
109        mPowerWarning = mContentView.findViewById(R.id.warning_unplugged);
110        mBatteryWarning = mContentView.findViewById(R.id.warning_low_charge);
111
112        return mContentView;
113    }
114
115    @Override
116    public void onResume() {
117        super.onResume();
118        getActivity().registerReceiver(mIntentReceiver, mIntentFilter);
119    }
120
121    @Override
122    public void onPause() {
123        super.onPause();
124        getActivity().unregisterReceiver(mIntentReceiver);
125    }
126
127    /**
128     * If encryption is already started, and this launched via a "start encryption" intent,
129     * then exit immediately - it's already up and running, so there's no point in "starting" it.
130     */
131    @Override
132    public void onActivityCreated(Bundle savedInstanceState) {
133        super.onActivityCreated(savedInstanceState);
134        Activity activity = getActivity();
135        Intent intent = activity.getIntent();
136        if (DevicePolicyManager.ACTION_START_ENCRYPTION.equals(intent.getAction())) {
137            DevicePolicyManager dpm = (DevicePolicyManager)
138                    activity.getSystemService(Context.DEVICE_POLICY_SERVICE);
139            if (dpm != null) {
140                int status = dpm.getStorageEncryptionStatus();
141                if (status != DevicePolicyManager.ENCRYPTION_STATUS_INACTIVE) {
142                    // There is nothing to do here, so simply finish() (which returns to caller)
143                    activity.finish();
144                }
145            }
146        }
147    }
148
149    /**
150     * Keyguard validation is run using the standard {@link ConfirmLockPattern}
151     * component as a subactivity
152     * @param request the request code to be returned once confirmation finishes
153     * @return true if confirmation launched
154     */
155    private boolean runKeyguardConfirmation(int request) {
156        Resources res = getActivity().getResources();
157        ChooseLockSettingsHelper helper = new ChooseLockSettingsHelper(getActivity(), this);
158
159        if (helper.utils().getKeyguardStoredPasswordQuality()
160                == DevicePolicyManager.PASSWORD_QUALITY_UNSPECIFIED) {
161            showFinalConfirmation(StorageManager.CRYPT_TYPE_DEFAULT, "");
162            return true;
163        }
164
165        return helper.launchConfirmationActivity(request,
166                res.getText(R.string.master_clear_gesture_prompt),
167                res.getText(R.string.crypt_keeper_confirm_encrypt),
168                true);
169    }
170
171    @Override
172    public void onActivityResult(int requestCode, int resultCode, Intent data) {
173        super.onActivityResult(requestCode, resultCode, data);
174
175        if (requestCode != KEYGUARD_REQUEST) {
176            return;
177        }
178
179        // If the user entered a valid keyguard trace, present the final
180        // confirmation prompt; otherwise, go back to the initial state.
181        if (resultCode == Activity.RESULT_OK && data != null) {
182            int type = data.getIntExtra(ChooseLockSettingsHelper.EXTRA_KEY_TYPE, -1);
183            String password = data.getStringExtra(ChooseLockSettingsHelper.EXTRA_KEY_PASSWORD);
184            if (!TextUtils.isEmpty(password)) {
185                showFinalConfirmation(type, password);
186            }
187        }
188    }
189
190    private void showFinalConfirmation(int type, String password) {
191        Preference preference = new Preference(getActivity());
192        preference.setFragment(CryptKeeperConfirm.class.getName());
193        preference.setTitle(R.string.crypt_keeper_confirm_title);
194        preference.getExtras().putInt("type", type);
195        preference.getExtras().putString("password", password);
196        ((SettingsActivity) getActivity()).onPreferenceStartFragment(null, preference);
197    }
198}
199