1 /* 2 * Copyright (C) 2017 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.network; 18 19 import static android.net.ConnectivitySettingsManager.PRIVATE_DNS_MODE_OFF; 20 import static android.net.ConnectivitySettingsManager.PRIVATE_DNS_MODE_OPPORTUNISTIC; 21 import static android.net.ConnectivitySettingsManager.PRIVATE_DNS_MODE_PROVIDER_HOSTNAME; 22 import static android.provider.Settings.Global.PRIVATE_DNS_DEFAULT_MODE; 23 import static android.provider.Settings.Global.PRIVATE_DNS_MODE; 24 import static android.provider.Settings.Global.PRIVATE_DNS_SPECIFIER; 25 26 import android.content.ContentResolver; 27 import android.content.Context; 28 import android.content.res.Resources; 29 import android.database.ContentObserver; 30 import android.net.ConnectivityManager; 31 import android.net.ConnectivityManager.NetworkCallback; 32 import android.net.ConnectivitySettingsManager; 33 import android.net.LinkProperties; 34 import android.net.Network; 35 import android.net.Uri; 36 import android.os.Handler; 37 import android.os.Looper; 38 import android.os.UserHandle; 39 import android.os.UserManager; 40 import android.provider.Settings; 41 42 import androidx.preference.Preference; 43 import androidx.preference.PreferenceScreen; 44 45 import com.android.internal.util.ArrayUtils; 46 import com.android.settings.R; 47 import com.android.settings.core.BasePreferenceController; 48 import com.android.settings.core.PreferenceControllerMixin; 49 import com.android.settingslib.RestrictedLockUtils.EnforcedAdmin; 50 import com.android.settingslib.RestrictedLockUtilsInternal; 51 import com.android.settingslib.core.lifecycle.LifecycleObserver; 52 import com.android.settingslib.core.lifecycle.events.OnStart; 53 import com.android.settingslib.core.lifecycle.events.OnStop; 54 55 import java.net.InetAddress; 56 import java.util.List; 57 58 public class PrivateDnsPreferenceController extends BasePreferenceController 59 implements PreferenceControllerMixin, LifecycleObserver, OnStart, OnStop { 60 private static final String KEY_PRIVATE_DNS_SETTINGS = "private_dns_settings"; 61 62 private static final Uri[] SETTINGS_URIS = new Uri[]{ 63 Settings.Global.getUriFor(PRIVATE_DNS_MODE), 64 Settings.Global.getUriFor(PRIVATE_DNS_DEFAULT_MODE), 65 Settings.Global.getUriFor(PRIVATE_DNS_SPECIFIER), 66 }; 67 68 private final Handler mHandler; 69 private final ContentObserver mSettingsObserver; 70 private final ConnectivityManager mConnectivityManager; 71 private LinkProperties mLatestLinkProperties; 72 private Preference mPreference; 73 PrivateDnsPreferenceController(Context context)74 public PrivateDnsPreferenceController(Context context) { 75 super(context, KEY_PRIVATE_DNS_SETTINGS); 76 mHandler = new Handler(Looper.getMainLooper()); 77 mSettingsObserver = new PrivateDnsSettingsObserver(mHandler); 78 mConnectivityManager = context.getSystemService(ConnectivityManager.class); 79 } 80 81 @Override getPreferenceKey()82 public String getPreferenceKey() { 83 return KEY_PRIVATE_DNS_SETTINGS; 84 } 85 86 @Override getAvailabilityStatus()87 public int getAvailabilityStatus() { 88 if (!mContext.getResources().getBoolean(R.bool.config_show_private_dns_settings)) { 89 return UNSUPPORTED_ON_DEVICE; 90 } 91 final UserManager userManager = mContext.getSystemService(UserManager.class); 92 if (userManager.isAdminUser()) return AVAILABLE; 93 return DISABLED_FOR_USER; 94 } 95 96 @Override displayPreference(PreferenceScreen screen)97 public void displayPreference(PreferenceScreen screen) { 98 super.displayPreference(screen); 99 100 mPreference = screen.findPreference(getPreferenceKey()); 101 } 102 103 @Override onStart()104 public void onStart() { 105 for (Uri uri : SETTINGS_URIS) { 106 mContext.getContentResolver().registerContentObserver(uri, false, mSettingsObserver); 107 } 108 final Network defaultNetwork = mConnectivityManager.getActiveNetwork(); 109 if (defaultNetwork != null) { 110 mLatestLinkProperties = mConnectivityManager.getLinkProperties(defaultNetwork); 111 } 112 mConnectivityManager.registerDefaultNetworkCallback(mNetworkCallback, mHandler); 113 } 114 115 @Override onStop()116 public void onStop() { 117 mContext.getContentResolver().unregisterContentObserver(mSettingsObserver); 118 mConnectivityManager.unregisterNetworkCallback(mNetworkCallback); 119 } 120 121 @Override getSummary()122 public CharSequence getSummary() { 123 final Resources res = mContext.getResources(); 124 final ContentResolver cr = mContext.getContentResolver(); 125 final int mode = ConnectivitySettingsManager.getPrivateDnsMode(mContext); 126 final LinkProperties lp = mLatestLinkProperties; 127 final List<InetAddress> dnses = (lp == null) ? null : lp.getValidatedPrivateDnsServers(); 128 final boolean dnsesResolved = !ArrayUtils.isEmpty(dnses); 129 switch (mode) { 130 case PRIVATE_DNS_MODE_OFF: 131 return res.getString(com.android.settingslib.R.string.private_dns_mode_off); 132 case PRIVATE_DNS_MODE_OPPORTUNISTIC: 133 return dnsesResolved ? res.getString(R.string.private_dns_mode_on) 134 : res.getString( 135 com.android.settingslib.R.string.private_dns_mode_opportunistic); 136 case PRIVATE_DNS_MODE_PROVIDER_HOSTNAME: 137 return dnsesResolved 138 ? PrivateDnsModeDialogPreference.getHostnameFromSettings(cr) 139 : res.getString( 140 com.android.settingslib.R.string.private_dns_mode_provider_failure); 141 } 142 return ""; 143 } 144 145 @Override updateState(Preference preference)146 public void updateState(Preference preference) { 147 super.updateState(preference); 148 preference.setEnabled(!isManagedByAdmin()); 149 } 150 isManagedByAdmin()151 private boolean isManagedByAdmin() { 152 EnforcedAdmin enforcedAdmin = RestrictedLockUtilsInternal.checkIfRestrictionEnforced( 153 mContext, UserManager.DISALLOW_CONFIG_PRIVATE_DNS, UserHandle.myUserId()); 154 return enforcedAdmin != null; 155 } 156 157 private class PrivateDnsSettingsObserver extends ContentObserver { PrivateDnsSettingsObserver(Handler h)158 public PrivateDnsSettingsObserver(Handler h) { 159 super(h); 160 } 161 162 @Override onChange(boolean selfChange)163 public void onChange(boolean selfChange) { 164 if (mPreference != null) { 165 updateState(mPreference); 166 } 167 } 168 } 169 170 private final NetworkCallback mNetworkCallback = new NetworkCallback() { 171 @Override 172 public void onLinkPropertiesChanged(Network network, LinkProperties lp) { 173 mLatestLinkProperties = lp; 174 if (mPreference != null) { 175 updateState(mPreference); 176 } 177 } 178 @Override 179 public void onLost(Network network) { 180 mLatestLinkProperties = null; 181 if (mPreference != null) { 182 updateState(mPreference); 183 } 184 } 185 }; 186 } 187