Merge "Fix DevSdkIgnoreRule for Q-" into main
diff --git a/staticlibs/Android.bp b/staticlibs/Android.bp
index e1b5601..d3e68b7 100644
--- a/staticlibs/Android.bp
+++ b/staticlibs/Android.bp
@@ -41,6 +41,7 @@
       "device/com/android/net/module/util/PacketReader.java",
       "device/com/android/net/module/util/SharedLog.java",
       "device/com/android/net/module/util/SocketUtils.java",
+      "device/com/android/net/module/util/FeatureVersions.java",
       // This library is used by system modules, for which the system health impact of Kotlin
       // has not yet been evaluated. Annotations may need jarjar'ing.
       // "src_devicecommon/**/*.kt",
diff --git a/staticlibs/device/com/android/net/module/util/DeviceConfigUtils.java b/staticlibs/device/com/android/net/module/util/DeviceConfigUtils.java
index 138c1e5..bea227d 100644
--- a/staticlibs/device/com/android/net/module/util/DeviceConfigUtils.java
+++ b/staticlibs/device/com/android/net/module/util/DeviceConfigUtils.java
@@ -17,6 +17,12 @@
 package com.android.net.module.util;
 
 import static android.content.pm.PackageManager.MATCH_SYSTEM_ONLY;
+import static android.provider.DeviceConfig.NAMESPACE_TETHERING;
+
+import static com.android.net.module.util.FeatureVersions.CONNECTIVITY_MODULE_ID;
+import static com.android.net.module.util.FeatureVersions.MODULE_MASK;
+import static com.android.net.module.util.FeatureVersions.NETWORK_STACK_MODULE_ID;
+import static com.android.net.module.util.FeatureVersions.VERSION_MASK;
 
 import android.content.Context;
 import android.content.Intent;
@@ -53,12 +59,14 @@
             "com.android.server.connectivity.intent.action.SERVICE_CONNECTIVITY_RESOURCES_APK";
     private static final String CONNECTIVITY_RES_PKG_DIR = "/apex/" + TETHERING_MODULE_NAME + "/";
 
-    private static final long DEFAULT_PACKAGE_VERSION = 1000;
+    @VisibleForTesting
+    public static final long DEFAULT_PACKAGE_VERSION = 1000;
 
     @VisibleForTesting
     public static void resetPackageVersionCacheForTest() {
         sPackageVersion = -1;
         sModuleVersion = -1;
+        sNetworkStackModuleVersion = -1;
     }
 
     private static volatile long sPackageVersion = -1;
@@ -224,14 +232,7 @@
     // If that fails retry by appending "go.tethering" instead
     private static long resolveTetheringModuleVersion(@NonNull Context context)
             throws PackageManager.NameNotFoundException {
-        final String connResourcesPackage = getConnectivityResourcesPackageName(context);
-        final int pkgPrefixLen = connResourcesPackage.indexOf("connectivity");
-        if (pkgPrefixLen < 0) {
-            throw new IllegalStateException(
-                    "Invalid connectivity resources package: " + connResourcesPackage);
-        }
-
-        final String pkgPrefix = connResourcesPackage.substring(0, pkgPrefixLen);
+        final String pkgPrefix = resolvePkgPrefix(context);
         final PackageManager packageManager = context.getPackageManager();
         try {
             return packageManager.getPackageInfo(pkgPrefix + "tethering",
@@ -245,6 +246,17 @@
                 PackageManager.MATCH_APEX).getLongVersionCode();
     }
 
+    private static String resolvePkgPrefix(Context context) {
+        final String connResourcesPackage = getConnectivityResourcesPackageName(context);
+        final int pkgPrefixLen = connResourcesPackage.indexOf("connectivity");
+        if (pkgPrefixLen < 0) {
+            throw new IllegalStateException(
+                    "Invalid connectivity resources package: " + connResourcesPackage);
+        }
+
+        return connResourcesPackage.substring(0, pkgPrefixLen);
+    }
+
     private static volatile long sModuleVersion = -1;
     private static long getTetheringModuleVersion(@NonNull Context context) {
         if (sModuleVersion >= 0) return sModuleVersion;
@@ -260,6 +272,80 @@
         return sModuleVersion;
     }
 
+    private static volatile long sNetworkStackModuleVersion = -1;
+
+    /**
+     * Get networkstack module version.
+     */
+    @VisibleForTesting
+    static long getNetworkStackModuleVersion(@NonNull Context context) {
+        if (sNetworkStackModuleVersion >= 0) return sNetworkStackModuleVersion;
+
+        try {
+            sNetworkStackModuleVersion = resolveNetworkStackModuleVersion(context);
+        } catch (PackageManager.NameNotFoundException e) {
+            Log.wtf(TAG, "Failed to resolve networkstack module version: " + e);
+            return DEFAULT_PACKAGE_VERSION;
+        }
+        return sNetworkStackModuleVersion;
+    }
+
+    private static long resolveNetworkStackModuleVersion(@NonNull Context context)
+            throws PackageManager.NameNotFoundException {
+        // TODO(b/293975546): Strictly speaking this is the prefix for connectivity and not
+        //  network stack. In practice, it's the same. Read the prefix from network stack instead.
+        final String pkgPrefix = resolvePkgPrefix(context);
+        final PackageManager packageManager = context.getPackageManager();
+        try {
+            return packageManager.getPackageInfo(pkgPrefix + "networkstack",
+                    PackageManager.MATCH_SYSTEM_ONLY).getLongVersionCode();
+        } catch (PackageManager.NameNotFoundException e) {
+            Log.d(TAG, "Device is using go or non-mainline modules");
+            // fall through
+        }
+
+        return packageManager.getPackageInfo(pkgPrefix + "go.networkstack",
+                PackageManager.MATCH_ALL).getLongVersionCode();
+    }
+
+    /**
+     * Check whether one specific feature is supported from the feature Id. The feature Id is
+     * composed by a module package Id and version Id from {@link FeatureVersions}.
+     *
+     * This is useful when a feature required minimal module version supported and cannot function
+     * well with a standalone newer module.
+     * @param context The global context information about an app environment.
+     * @param featureId The feature id that contains required module id and minimal module version
+     * @return true if this feature is supported, or false if not supported.
+     **/
+    public static boolean isFeatureSupported(@NonNull Context context, long featureId) {
+        final long moduleVersion;
+        final long moduleId = featureId & MODULE_MASK;
+        if (moduleId == CONNECTIVITY_MODULE_ID) {
+            moduleVersion = getTetheringModuleVersion(context);
+        } else if (moduleId == NETWORK_STACK_MODULE_ID) {
+            moduleVersion = getNetworkStackModuleVersion(context);
+        } else {
+            throw new IllegalArgumentException("Unknown module " + moduleId);
+        }
+        // Support by default if no module version is available.
+        return moduleVersion == DEFAULT_PACKAGE_VERSION
+                || moduleVersion >= (featureId & VERSION_MASK);
+    }
+
+    /**
+     * Check whether one specific experimental feature in tethering module from {@link DeviceConfig}
+     * is disabled by setting a non-zero value in the property.
+     *
+     * @param name The name of the property to look up.
+     * @return true if this feature is force disabled, or false if not disabled.
+     */
+    public static boolean isTetheringFeatureForceDisabled(String name) {
+        final int propertyVersion = getDeviceConfigPropertyInt(NAMESPACE_TETHERING, name,
+                0 /* default value */);
+        return propertyVersion != 0;
+    }
+
     /**
      * Gets boolean config from resources.
      */
diff --git a/staticlibs/device/com/android/net/module/util/FeatureVersions.java b/staticlibs/device/com/android/net/module/util/FeatureVersions.java
new file mode 100644
index 0000000..4986a58
--- /dev/null
+++ b/staticlibs/device/com/android/net/module/util/FeatureVersions.java
@@ -0,0 +1,34 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.net.module.util;
+
+/**
+ * Class to centralize feature version control that requires a specific module or a specific
+ * module version.
+ * @hide
+ */
+public class FeatureVersions {
+    public static final long MODULE_MASK = 0xFF00_000000000L;
+    public static final long VERSION_MASK = 0x0000_FFFFFFFFFL;
+    public static final long CONNECTIVITY_MODULE_ID = 0x0100_000000000L;
+    public static final long NETWORK_STACK_MODULE_ID = 0x0200_000000000L;
+    // CLAT_ADDRESS_TRANSLATE is a feature of the network stack, which doesn't throw when system
+    // try to add a NAT-T keepalive packet filter with v6 address, introduced in version
+    // M-2023-Sept on July 3rd, 2023.
+    public static final long FEATURE_CLAT_ADDRESS_TRANSLATE =
+            NETWORK_STACK_MODULE_ID + 340900000L;
+}
diff --git a/staticlibs/device/com/android/net/module/util/SharedLog.java b/staticlibs/device/com/android/net/module/util/SharedLog.java
index 17b061e..6b12c80 100644
--- a/staticlibs/device/com/android/net/module/util/SharedLog.java
+++ b/staticlibs/device/com/android/net/module/util/SharedLog.java
@@ -46,6 +46,8 @@
         ERROR,
         MARK,
         WARN,
+        VERBOSE,
+        TERRIBLE,
     }
 
     private final LocalLog mLocalLog;
@@ -159,6 +161,41 @@
         Log.w(mTag, record(Category.WARN, msg));
     }
 
+    /**
+     * Log a verbose message.
+     *
+     * <p>The log entry will be also added to the system log.
+     */
+    public void v(String msg) {
+        Log.v(mTag, record(Category.VERBOSE, msg));
+    }
+
+    /**
+     * Log a terrible failure message.
+     *
+     * <p>The log entry will be also added to the system log and will trigger system reporting
+     * for terrible failures.
+     */
+    public void wtf(String msg) {
+        Log.wtf(mTag, record(Category.TERRIBLE, msg));
+    }
+
+    /**
+     * Log a terrible failure due to an exception, with the exception stacktrace if provided.
+     *
+     * <p>The error and exception message appear in the shared log, but the stacktrace is only
+     * logged in general log output (logcat). The log entry will be also added to the system log
+     * and will trigger system reporting for terrible failures.
+     */
+    public void wtf(@NonNull String msg, @Nullable Throwable exception) {
+        if (exception == null) {
+            e(msg);
+            return;
+        }
+        Log.wtf(mTag, record(Category.TERRIBLE, msg + ": " + exception.getMessage()), exception);
+    }
+
+
     //////
     // Methods that only log an entry (and do NOT emit to the system log).
     //////
diff --git a/staticlibs/framework/com/android/net/module/util/NetworkStackConstants.java b/staticlibs/framework/com/android/net/module/util/NetworkStackConstants.java
index 24aabbc..9149160 100644
--- a/staticlibs/framework/com/android/net/module/util/NetworkStackConstants.java
+++ b/staticlibs/framework/com/android/net/module/util/NetworkStackConstants.java
@@ -17,6 +17,7 @@
 package com.android.net.module.util;
 
 import android.net.InetAddresses;
+import android.net.IpPrefix;
 
 import java.net.Inet4Address;
 import java.net.Inet6Address;
@@ -99,6 +100,8 @@
     public static final int IPV4_ADDR_LEN = 4;
     public static final int IPV4_FLAG_MF = 0x2000;
     public static final int IPV4_FLAG_DF = 0x4000;
+    // getSockOpt() for v4 MTU
+    public static final int IP_MTU = 14;
     public static final Inet4Address IPV4_ADDR_ALL = makeInet4Address(
             (byte) 0xff, (byte) 0xff, (byte) 0xff, (byte) 0xff);
     public static final Inet4Address IPV4_ADDR_ANY = makeInet4Address(
@@ -108,6 +111,12 @@
             (byte) 0, (byte) 0, (byte) 0, (byte) 0,
             (byte) 0, (byte) 0, (byte) 0, (byte) 0,
             (byte) 0, (byte) 0, (byte) 0, (byte) 0 });
+
+    /**
+     * CLAT constants
+     */
+    public static final IpPrefix CLAT_PREFIX = new IpPrefix("192.0.0.0/29");
+
     /**
      * IPv6 constants.
      *
@@ -121,6 +130,10 @@
     public static final int IPV6_SRC_ADDR_OFFSET = 8;
     public static final int IPV6_DST_ADDR_OFFSET = 24;
     public static final int IPV6_MIN_MTU = 1280;
+    public static final int IPV6_FRAGMENT_HEADER_LEN = 8;
+    public static final int RFC7421_PREFIX_LENGTH = 64;
+    // getSockOpt() for v6 MTU
+    public static final int IPV6_MTU = 24;
     public static final Inet6Address IPV6_ADDR_ALL_NODES_MULTICAST =
             (Inet6Address) InetAddresses.parseNumericAddress("ff02::1");
     public static final Inet6Address IPV6_ADDR_ALL_ROUTERS_MULTICAST =
diff --git a/staticlibs/tests/unit/src/com/android/net/module/util/DeviceConfigUtilsTest.java b/staticlibs/tests/unit/src/com/android/net/module/util/DeviceConfigUtilsTest.java
index 328c39a..7946244 100644
--- a/staticlibs/tests/unit/src/com/android/net/module/util/DeviceConfigUtilsTest.java
+++ b/staticlibs/tests/unit/src/com/android/net/module/util/DeviceConfigUtilsTest.java
@@ -17,12 +17,16 @@
 package com.android.net.module.util;
 
 import static android.content.pm.PackageManager.MATCH_SYSTEM_ONLY;
+import static android.provider.DeviceConfig.NAMESPACE_TETHERING;
 
 import static com.android.dx.mockito.inline.extended.ExtendedMockito.doReturn;
 import static com.android.dx.mockito.inline.extended.ExtendedMockito.mockitoSession;
+import static com.android.net.module.util.FeatureVersions.CONNECTIVITY_MODULE_ID;
+import static com.android.net.module.util.FeatureVersions.NETWORK_STACK_MODULE_ID;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertThrows;
 import static org.junit.Assert.assertTrue;
 import static org.mockito.ArgumentMatchers.argThat;
 import static org.mockito.Mockito.anyInt;
@@ -84,6 +88,8 @@
     private static final String TEST_GO_APEX_PACKAGE_NAME = "com.prefix.android.go.tethering";
     private static final String TEST_CONNRES_PACKAGE_NAME =
             "com.prefix.android.connectivity.resources";
+    private static final String TEST_NETWORKSTACK_NAME = "com.prefix.android.networkstack";
+    private static final String TEST_GO_NETWORKSTACK_NAME = "com.prefix.android.go.networkstack";
     private final PackageInfo mPackageInfo = new PackageInfo();
     private final PackageInfo mApexPackageInfo = new PackageInfo();
     private MockitoSession mSession;
@@ -346,4 +352,82 @@
         doThrow(new Resources.NotFoundException()).when(mResources).getInteger(someResId);
         assertEquals(2098, DeviceConfigUtils.getResIntegerConfig(mContext, someResId, 2098));
     }
+
+    @Test
+    public void testGetNetworkStackModuleVersionCaching() throws Exception {
+        final PackageInfo networkStackPackageInfo = new PackageInfo();
+        networkStackPackageInfo.setLongVersionCode(TEST_PACKAGE_VERSION);
+        doReturn(networkStackPackageInfo).when(mPm).getPackageInfo(
+                eq(TEST_NETWORKSTACK_NAME), anyInt());
+        assertEquals(TEST_PACKAGE_VERSION,
+                DeviceConfigUtils.getNetworkStackModuleVersion(mContext));
+
+        assertEquals(TEST_PACKAGE_VERSION,
+                DeviceConfigUtils.getNetworkStackModuleVersion(mContext));
+        // Package info is only queried once
+        verify(mPm, times(1)).getPackageInfo(anyString(), anyInt());
+        verify(mContext, never()).getPackageName();
+    }
+
+    @Test
+    public void testGetNetworkStackModuleVersionOnNonMainline() {
+        assertEquals(DeviceConfigUtils.DEFAULT_PACKAGE_VERSION,
+                DeviceConfigUtils.getNetworkStackModuleVersion(mContext));
+    }
+
+    @Test
+    public void testGetNetworkStackModuleVersion() throws Exception {
+        final PackageInfo networkStackPackageInfo = new PackageInfo();
+        final PackageInfo goNetworkStackPackageInfo = new PackageInfo();
+        networkStackPackageInfo.setLongVersionCode(TEST_PACKAGE_VERSION);
+        goNetworkStackPackageInfo.setLongVersionCode(TEST_PACKAGE_VERSION + 1);
+        doReturn(goNetworkStackPackageInfo).when(mPm).getPackageInfo(
+                eq(TEST_NETWORKSTACK_NAME), anyInt());
+        // Verify the returned value is go module version.
+        assertEquals(TEST_PACKAGE_VERSION + 1,
+                DeviceConfigUtils.getNetworkStackModuleVersion(mContext));
+    }
+
+    @Test
+    public void testIsFeatureSupported_networkStackFeature() throws Exception {
+        // Supported for DEFAULT_PACKAGE_VERSION
+        assertTrue(DeviceConfigUtils.isFeatureSupported(
+                mContext, TEST_PACKAGE_VERSION + NETWORK_STACK_MODULE_ID));
+
+        final PackageInfo networkStackPackageInfo = new PackageInfo();
+        networkStackPackageInfo.setLongVersionCode(TEST_PACKAGE_VERSION);
+        doReturn(networkStackPackageInfo).when(mPm).getPackageInfo(
+                eq(TEST_NETWORKSTACK_NAME), anyInt());
+
+        assertTrue(DeviceConfigUtils.isFeatureSupported(
+                mContext, TEST_PACKAGE_VERSION + NETWORK_STACK_MODULE_ID));
+        assertFalse(DeviceConfigUtils.isFeatureSupported(
+                mContext, TEST_PACKAGE_VERSION + NETWORK_STACK_MODULE_ID + 1));
+    }
+
+    @Test
+    public void testIsFeatureSupported_tetheringFeature() throws Exception {
+        assertTrue(DeviceConfigUtils.isFeatureSupported(
+                mContext, TEST_PACKAGE_VERSION + CONNECTIVITY_MODULE_ID));
+        // Return false because feature requires a future version.
+        assertFalse(DeviceConfigUtils.isFeatureSupported(
+                mContext, 889900000L + CONNECTIVITY_MODULE_ID));
+    }
+
+    @Test
+    public void testIsFeatureSupported_illegalModule() throws Exception {
+        assertThrows(IllegalArgumentException.class,
+                () -> DeviceConfigUtils.isFeatureSupported(mContext, TEST_PACKAGE_VERSION));
+    }
+
+    @Test
+    public void testIsTetheringFeatureForceDisabled() throws Exception {
+        doReturn("0").when(() -> DeviceConfig.getProperty(
+                eq(NAMESPACE_TETHERING), eq(TEST_EXPERIMENT_FLAG)));
+        assertFalse(DeviceConfigUtils.isTetheringFeatureForceDisabled(TEST_EXPERIMENT_FLAG));
+
+        doReturn(TEST_FLAG_VALUE_STRING).when(
+                () -> DeviceConfig.getProperty(eq(NAMESPACE_TETHERING), eq(TEST_EXPERIMENT_FLAG)));
+        assertTrue(DeviceConfigUtils.isTetheringFeatureForceDisabled(TEST_EXPERIMENT_FLAG));
+    }
 }
diff --git a/staticlibs/testutils/app/connectivitychecker/src/com/android/testutils/connectivitypreparer/ConnectivityCheckTest.kt b/staticlibs/testutils/app/connectivitychecker/src/com/android/testutils/connectivitypreparer/ConnectivityCheckTest.kt
index 6bcb8fc..f1f0975 100644
--- a/staticlibs/testutils/app/connectivitychecker/src/com/android/testutils/connectivitypreparer/ConnectivityCheckTest.kt
+++ b/staticlibs/testutils/app/connectivitychecker/src/com/android/testutils/connectivitypreparer/ConnectivityCheckTest.kt
@@ -72,7 +72,7 @@
         val cb = TestableNetworkCallback()
         val cm = context.getSystemService(ConnectivityManager::class.java)
                 ?: fail("Could not get ConnectivityManager")
-        cm.registerNetworkCallback(
+        cm.requestNetwork(
                 NetworkRequest.Builder()
                         .addTransportType(TRANSPORT_CELLULAR)
                         .addCapability(NET_CAPABILITY_INTERNET).build(), cb)