Migrate legacy dhcp server config to DeviceConfig

Legacy dhcp server can also be enabled by resource config.

Bug: 144814607
Test: -build, flash, boot
      -atest TetheringTests

Change-Id: I8ae5fa3d5bbd88129bd0890f71be6f8a1bfec0eb

Tethering/AndroidManifest.xml

@@ -32,6 +32,7 @@
     <uses-permission android:name="android.permission.CHANGE_NETWORK_STATE" />
     <uses-permission android:name="android.permission.MANAGE_USB" />
     <uses-permission android:name="android.permission.MODIFY_PHONE_STATE" />
+    <uses-permission android:name="android.permission.READ_DEVICE_CONFIG" />
     <uses-permission android:name="android.permission.READ_NETWORK_USAGE_HISTORY" />
     <uses-permission android:name="android.permission.TETHER_PRIVILEGED" />
     <uses-permission android:name="android.permission.UPDATE_APP_OPS_STATS" />

Tethering/res/values/config.xml

@@ -49,6 +49,9 @@
         <item>"bt-pan"</item>
     </string-array>
 
+    <!-- Use the old dnsmasq DHCP server for tethering instead of the framework implementation. -->
+    <bool translatable="false" name="config_tether_enable_legacy_dhcp_server">false</bool>
+
     <!-- Dhcp range (min, max) to use for tethering purposes -->
     <string-array translatable="false" name="config_tether_dhcp_range">
     </string-array>

Tethering/res/values/overlayable.xml

@@ -21,6 +21,7 @@
             <item type="array" name="config_tether_wifi_p2p_regexs"/>
             <item type="array" name="config_tether_bluetooth_regexs"/>
             <item type="array" name="config_tether_dhcp_range"/>
+            <item type="bool" name="config_tether_enable_legacy_dhcp_server"/>
             <item type="array" name="config_tether_upstream_types"/>
             <item type="bool" name="config_tether_upstream_automatic"/>
             <!-- Configuration values for tethering entitlement check -->

Tethering/src/com/android/server/connectivity/tethering/TetheringConfiguration.java

@@ -21,7 +21,7 @@ import static android.net.ConnectivityManager.TYPE_ETHERNET;
 import static android.net.ConnectivityManager.TYPE_MOBILE;
 import static android.net.ConnectivityManager.TYPE_MOBILE_DUN;
 import static android.net.ConnectivityManager.TYPE_MOBILE_HIPRI;
-import static android.provider.Settings.Global.TETHER_ENABLE_LEGACY_DHCP_SERVER;
+import static android.provider.DeviceConfig.NAMESPACE_CONNECTIVITY;
 
 import static com.android.internal.R.array.config_mobile_hotspot_provision_app;
 import static com.android.internal.R.array.config_tether_bluetooth_regexs;
@@ -33,13 +33,13 @@ import static com.android.internal.R.array.config_tether_wifi_regexs;
 import static com.android.internal.R.bool.config_tether_upstream_automatic;
 import static com.android.internal.R.integer.config_mobile_hotspot_provision_check_period;
 import static com.android.internal.R.string.config_mobile_hotspot_provision_app_no_ui;
+import static com.android.networkstack.tethering.R.bool.config_tether_enable_legacy_dhcp_server;
 
-import android.content.ContentResolver;
 import android.content.Context;
 import android.content.res.Resources;
 import android.net.TetheringConfigurationParcel;
 import android.net.util.SharedLog;
-import android.provider.Settings;
+import android.provider.DeviceConfig;
 import android.telephony.SubscriptionManager;
 import android.telephony.TelephonyManager;
 import android.text.TextUtils;
@@ -84,6 +84,12 @@ public class TetheringConfiguration {
 
     private static final String[] DEFAULT_IPV4_DNS = {"8.8.4.4", "8.8.8.8"};
 
+    /**
+     * Use the old dnsmasq DHCP server for tethering instead of the framework implementation.
+     */
+    public static final String TETHER_ENABLE_LEGACY_DHCP_SERVER =
+            "tether_enable_legacy_dhcp_server";
+
     public final String[] tetherableUsbRegexs;
     public final String[] tetherableWifiRegexs;
     public final String[] tetherableWifiP2pRegexs;
@@ -122,7 +128,7 @@ public class TetheringConfiguration {
 
         legacyDhcpRanges = getLegacyDhcpRanges(res);
         defaultIPv4DNS = copy(DEFAULT_IPV4_DNS);
-        enableLegacyDhcpServer = getEnableLegacyDhcpServer(ctx);
+        enableLegacyDhcpServer = getEnableLegacyDhcpServer(res);
 
         provisioningApp = getResourceStringArray(res, config_mobile_hotspot_provision_app);
         provisioningAppNoUi = getProvisioningAppNoUi(res);
@@ -332,10 +338,14 @@ public class TetheringConfiguration {
         }
     }
 
-    private static boolean getEnableLegacyDhcpServer(Context ctx) {
+    private boolean getEnableLegacyDhcpServer(final Resources res) {
-        final ContentResolver cr = ctx.getContentResolver();
+        return getResourceBoolean(res, config_tether_enable_legacy_dhcp_server)
-        final int intVal = Settings.Global.getInt(cr, TETHER_ENABLE_LEGACY_DHCP_SERVER, 0);
+                || getDeviceConfigBoolean(TETHER_ENABLE_LEGACY_DHCP_SERVER);
-        return intVal != 0;
+    }
+
+    @VisibleForTesting
+    protected boolean getDeviceConfigBoolean(final String name) {
+        return DeviceConfig.getBoolean(NAMESPACE_CONNECTIVITY, name, false /** defaultValue */);
     }
 
     private Resources getResources(Context ctx, int subId) {

Tethering/tests/unit/src/com/android/server/connectivity/tethering/EntitlementManagerTest.java

@@ -22,10 +22,12 @@ import static android.net.TetheringManager.TETHERING_WIFI;
 import static android.net.TetheringManager.TETHER_ERROR_ENTITLEMENT_UNKONWN;
 import static android.net.TetheringManager.TETHER_ERROR_NO_ERROR;
 import static android.net.TetheringManager.TETHER_ERROR_PROVISION_FAILED;
+import static android.provider.DeviceConfig.NAMESPACE_CONNECTIVITY;
 import static android.telephony.SubscriptionManager.INVALID_SUBSCRIPTION_ID;
 
 import static com.android.dx.mockito.inline.extended.ExtendedMockito.doReturn;
 import static com.android.dx.mockito.inline.extended.ExtendedMockito.mockitoSession;
+import static com.android.networkstack.tethering.R.bool.config_tether_enable_legacy_dhcp_server;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
@@ -39,7 +41,6 @@ import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
-import android.content.ContentResolver;
 import android.content.Context;
 import android.content.res.Resources;
 import android.net.util.SharedLog;
@@ -49,9 +50,8 @@ import android.os.PersistableBundle;
 import android.os.ResultReceiver;
 import android.os.SystemProperties;
 import android.os.test.TestLooper;
-import android.provider.Settings;
+import android.provider.DeviceConfig;
 import android.telephony.CarrierConfigManager;
-import android.test.mock.MockContentResolver;
 
 import androidx.test.filters.SmallTest;
 import androidx.test.runner.AndroidJUnit4;
@@ -60,7 +60,6 @@ import com.android.internal.R;
 import com.android.internal.util.State;
 import com.android.internal.util.StateMachine;
 import com.android.internal.util.test.BroadcastInterceptingContext;
-import com.android.internal.util.test.FakeSettingsProvider;
 
 import org.junit.After;
 import org.junit.Before;
@@ -94,7 +93,6 @@ public final class EntitlementManagerTest {
     private final PersistableBundle mCarrierConfig = new PersistableBundle();
     private final TestLooper mLooper = new TestLooper();
     private Context mMockContext;
-    private MockContentResolver mContentResolver;
 
     private TestStateMachine mSM;
     private WrappedEntitlementManager mEnMgr;
@@ -110,11 +108,6 @@ public final class EntitlementManagerTest {
         public Resources getResources() {
             return mResources;
         }
-
-        @Override
-        public ContentResolver getContentResolver() {
-            return mContentResolver;
-        }
     }
 
     public class WrappedEntitlementManager extends EntitlementManager {
@@ -151,13 +144,17 @@ public final class EntitlementManagerTest {
         MockitoAnnotations.initMocks(this);
         mMockingSession = mockitoSession()
                 .initMocks(this)
-                .spyStatic(SystemProperties.class)
+                .mockStatic(SystemProperties.class)
+                .mockStatic(DeviceConfig.class)
                 .strictness(Strictness.WARN)
                 .startMocking();
         // Don't disable tethering provisioning unless requested.
         doReturn(false).when(
                 () -> SystemProperties.getBoolean(
                 eq(EntitlementManager.DISABLE_PROVISIONING_SYSPROP_KEY), anyBoolean()));
+        doReturn(false).when(
+                () -> DeviceConfig.getBoolean(eq(NAMESPACE_CONNECTIVITY),
+                eq(TetheringConfiguration.TETHER_ENABLE_LEGACY_DHCP_SERVER), anyBoolean()));
 
         when(mResources.getStringArray(R.array.config_tether_dhcp_range))
             .thenReturn(new String[0]);
@@ -169,10 +166,9 @@ public final class EntitlementManagerTest {
             .thenReturn(new String[0]);
         when(mResources.getIntArray(R.array.config_tether_upstream_types))
             .thenReturn(new int[0]);
+        when(mResources.getBoolean(config_tether_enable_legacy_dhcp_server)).thenReturn(false);
         when(mLog.forSubComponent(anyString())).thenReturn(mLog);
 
-        mContentResolver = new MockContentResolver();
-        mContentResolver.addProvider(Settings.AUTHORITY, new FakeSettingsProvider());
         mMockContext = new MockContext(mContext);
         mSM = new TestStateMachine();
         mEnMgr = new WrappedEntitlementManager(mMockContext, mSM, mLog, EVENT_EM_UPDATE);

Tethering/tests/unit/src/com/android/server/connectivity/tethering/TetheringConfigurationTest.java

@@ -21,40 +21,44 @@ import static android.net.ConnectivityManager.TYPE_MOBILE;
 import static android.net.ConnectivityManager.TYPE_MOBILE_DUN;
 import static android.net.ConnectivityManager.TYPE_MOBILE_HIPRI;
 import static android.net.ConnectivityManager.TYPE_WIFI;
-import static android.provider.Settings.Global.TETHER_ENABLE_LEGACY_DHCP_SERVER;
+import static android.provider.DeviceConfig.NAMESPACE_CONNECTIVITY;
 import static android.telephony.SubscriptionManager.INVALID_SUBSCRIPTION_ID;
 
+import static com.android.dx.mockito.inline.extended.ExtendedMockito.doReturn;
+import static com.android.dx.mockito.inline.extended.ExtendedMockito.mockitoSession;
 import static com.android.internal.R.array.config_mobile_hotspot_provision_app;
 import static com.android.internal.R.array.config_tether_bluetooth_regexs;
 import static com.android.internal.R.array.config_tether_dhcp_range;
 import static com.android.internal.R.array.config_tether_upstream_types;
 import static com.android.internal.R.array.config_tether_usb_regexs;
 import static com.android.internal.R.array.config_tether_wifi_regexs;
+import static com.android.networkstack.tethering.R.bool.config_tether_enable_legacy_dhcp_server;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
+import static org.mockito.Matchers.anyBoolean;
+import static org.mockito.Matchers.eq;
 import static org.mockito.Mockito.when;
 
-import android.content.ContentResolver;
 import android.content.Context;
 import android.content.res.Resources;
 import android.net.util.SharedLog;
-import android.provider.Settings;
+import android.provider.DeviceConfig;
 import android.telephony.TelephonyManager;
-import android.test.mock.MockContentResolver;
 
 import androidx.test.filters.SmallTest;
 import androidx.test.runner.AndroidJUnit4;
 
 import com.android.internal.util.test.BroadcastInterceptingContext;
-import com.android.internal.util.test.FakeSettingsProvider;
 
+import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.mockito.Mock;
-import org.mockito.MockitoAnnotations;
+import org.mockito.MockitoSession;
+import org.mockito.quality.Strictness;
 
 import java.util.Arrays;
 import java.util.Iterator;
@@ -69,9 +73,10 @@ public class TetheringConfigurationTest {
     @Mock private TelephonyManager mTelephonyManager;
     @Mock private Resources mResources;
     @Mock private Resources mResourcesForSubId;
-    private MockContentResolver mContentResolver;
     private Context mMockContext;
     private boolean mHasTelephonyManager;
+    private boolean mEnableLegacyDhcpServer;
+    private MockitoSession mMockingSession;
 
     private class MockTetheringConfiguration extends TetheringConfiguration {
         MockTetheringConfiguration(Context ctx, SharedLog log, int id) {
@@ -101,16 +106,20 @@ public class TetheringConfigurationTest {
             }
             return super.getSystemService(name);
         }
-
-        @Override
-        public ContentResolver getContentResolver() {
-            return mContentResolver;
-        }
     }
 
     @Before
     public void setUp() throws Exception {
-        MockitoAnnotations.initMocks(this);
+        // TODO: use a dependencies class instead of mock statics.
+        mMockingSession = mockitoSession()
+                .initMocks(this)
+                .mockStatic(DeviceConfig.class)
+                .strictness(Strictness.WARN)
+                .startMocking();
+        doReturn(false).when(
+                () -> DeviceConfig.getBoolean(eq(NAMESPACE_CONNECTIVITY),
+                eq(TetheringConfiguration.TETHER_ENABLE_LEGACY_DHCP_SERVER), anyBoolean()));
+
         when(mResources.getStringArray(config_tether_dhcp_range)).thenReturn(new String[0]);
         when(mResources.getStringArray(config_tether_usb_regexs)).thenReturn(new String[0]);
         when(mResources.getStringArray(config_tether_wifi_regexs))
@@ -119,10 +128,15 @@ public class TetheringConfigurationTest {
         when(mResources.getIntArray(config_tether_upstream_types)).thenReturn(new int[0]);
         when(mResources.getStringArray(config_mobile_hotspot_provision_app))
                 .thenReturn(new String[0]);
-        mContentResolver = new MockContentResolver();
+        when(mResources.getBoolean(config_tether_enable_legacy_dhcp_server)).thenReturn(false);
-        mContentResolver.addProvider(Settings.AUTHORITY, new FakeSettingsProvider());
         mHasTelephonyManager = true;
         mMockContext = new MockContext(mContext);
+        mEnableLegacyDhcpServer = false;
+    }
+
+    @After
+    public void tearDown() throws Exception {
+        mMockingSession.finishMocking();
     }
 
     private TetheringConfiguration getTetheringConfiguration(int... legacyTetherUpstreamTypes) {
@@ -268,19 +282,35 @@ public class TetheringConfigurationTest {
 
     @Test
     public void testNewDhcpServerDisabled() {
-        Settings.Global.putInt(mContentResolver, TETHER_ENABLE_LEGACY_DHCP_SERVER, 1);
+        when(mResources.getBoolean(config_tether_enable_legacy_dhcp_server)).thenReturn(true);
+        doReturn(false).when(
+                () -> DeviceConfig.getBoolean(eq(NAMESPACE_CONNECTIVITY),
+                eq(TetheringConfiguration.TETHER_ENABLE_LEGACY_DHCP_SERVER), anyBoolean()));
 
-        final TetheringConfiguration cfg = new TetheringConfiguration(
+        final TetheringConfiguration enableByRes =
-                mMockContext, mLog, INVALID_SUBSCRIPTION_ID);
+                new TetheringConfiguration(mMockContext, mLog, INVALID_SUBSCRIPTION_ID);
-        assertTrue(cfg.enableLegacyDhcpServer);
+        assertTrue(enableByRes.enableLegacyDhcpServer);
+
+        when(mResources.getBoolean(config_tether_enable_legacy_dhcp_server)).thenReturn(false);
+        doReturn(true).when(
+                () -> DeviceConfig.getBoolean(eq(NAMESPACE_CONNECTIVITY),
+                eq(TetheringConfiguration.TETHER_ENABLE_LEGACY_DHCP_SERVER), anyBoolean()));
+
+        final TetheringConfiguration enableByDevConfig =
+                new TetheringConfiguration(mMockContext, mLog, INVALID_SUBSCRIPTION_ID);
+        assertTrue(enableByDevConfig.enableLegacyDhcpServer);
     }
 
     @Test
     public void testNewDhcpServerEnabled() {
-        Settings.Global.putInt(mContentResolver, TETHER_ENABLE_LEGACY_DHCP_SERVER, 0);
+        when(mResources.getBoolean(config_tether_enable_legacy_dhcp_server)).thenReturn(false);
+        doReturn(false).when(
+                () -> DeviceConfig.getBoolean(eq(NAMESPACE_CONNECTIVITY),
+                eq(TetheringConfiguration.TETHER_ENABLE_LEGACY_DHCP_SERVER), anyBoolean()));
+
+        final TetheringConfiguration cfg =
+                new TetheringConfiguration(mMockContext, mLog, INVALID_SUBSCRIPTION_ID);
 
-        final TetheringConfiguration cfg = new TetheringConfiguration(
-                mMockContext, mLog, INVALID_SUBSCRIPTION_ID);
         assertFalse(cfg.enableLegacyDhcpServer);
     }
 

Tethering/tests/unit/src/com/android/server/connectivity/tethering/TetheringTest.java

@@ -35,9 +35,10 @@ import static android.net.wifi.WifiManager.EXTRA_WIFI_AP_STATE;
 import static android.net.wifi.WifiManager.IFACE_IP_MODE_LOCAL_ONLY;
 import static android.net.wifi.WifiManager.IFACE_IP_MODE_TETHERED;
 import static android.net.wifi.WifiManager.WIFI_AP_STATE_ENABLED;
-import static android.provider.Settings.Global.TETHER_ENABLE_LEGACY_DHCP_SERVER;
 import static android.telephony.SubscriptionManager.INVALID_SUBSCRIPTION_ID;
 
+import static com.android.networkstack.tethering.R.bool.config_tether_enable_legacy_dhcp_server;
+
 import static org.junit.Assert.assertArrayEquals;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
@@ -269,6 +270,11 @@ public class TetheringTest {
             super(ctx, log, id);
         }
 
+        @Override
+        protected boolean getDeviceConfigBoolean(final String name) {
+            return false;
+        }
+
         @Override
         protected Resources getResourcesForSubIdWrapper(Context ctx, int subId) {
             return mResources;
@@ -428,6 +434,7 @@ public class TetheringTest {
                 .thenReturn(new int[0]);
         when(mResources.getBoolean(com.android.internal.R.bool.config_tether_upstream_automatic))
                 .thenReturn(false);
+        when(mResources.getBoolean(config_tether_enable_legacy_dhcp_server)).thenReturn(false);
         when(mNetd.interfaceGetList())
                 .thenReturn(new String[] {
                         TEST_MOBILE_IFNAME, TEST_WLAN_IFNAME, TEST_USB_IFNAME, TEST_P2P_IFNAME});
@@ -440,7 +447,6 @@ public class TetheringTest {
         when(mContext.getSystemService(Context.NOTIFICATION_SERVICE)).thenReturn(null);
         mContentResolver = new MockContentResolver(mServiceContext);
         mContentResolver.addProvider(Settings.AUTHORITY, new FakeSettingsProvider());
-        Settings.Global.putInt(mContentResolver, TETHER_ENABLE_LEGACY_DHCP_SERVER, 0);
         mIntents = new Vector<>();
         mBroadcastReceiver = new BroadcastReceiver() {
             @Override
@@ -692,7 +698,7 @@ public class TetheringTest {
 
     @Test
     public void workingMobileUsbTethering_IPv4LegacyDhcp() {
-        Settings.Global.putInt(mContentResolver, TETHER_ENABLE_LEGACY_DHCP_SERVER, 1);
+        when(mResources.getBoolean(config_tether_enable_legacy_dhcp_server)).thenReturn(true);
         sendConfigurationChanged();
         final UpstreamNetworkState upstreamState = buildMobileIPv4UpstreamState();
         runUsbTethering(upstreamState);