Implement TestNetworkService
This change adds the relevant JNI implementations, as well as the
implementations and NetworkAgent tracking code in the TestNetworkService.
TestNetworkService (And Manager) is designed for use exclusively in
testing code, allowing for the creation of TUN and IPsec backed networks
in test code. Specifically, this allows for testing of components such
as IP, DHCP, or DNS clients, as well as kernel features such as IPsec.
Access to the TestNetworkService will be conditioned upon the
MANAGE_TEST_NETWORKS permission that will be granted only to the Shell.
CTS will use UiAutomation.adoptShellPermissionIdentity() to gain the
ability to use this service.
Bug: 72950854
Test: CTS tests passing
Change-Id: Ie66ba631a548b5f9c6b5ed0797582f86688debe5
diff --git a/services/core/java/com/android/server/TestNetworkService.java b/services/core/java/com/android/server/TestNetworkService.java
index 013e9cc..e64ab78 100644
--- a/services/core/java/com/android/server/TestNetworkService.java
+++ b/services/core/java/com/android/server/TestNetworkService.java
@@ -20,23 +20,47 @@
import android.annotation.NonNull;
import android.content.Context;
+import android.net.ConnectivityManager;
import android.net.INetd;
import android.net.ITestNetworkManager;
+import android.net.IpPrefix;
import android.net.LinkAddress;
+import android.net.LinkProperties;
+import android.net.NetworkAgent;
+import android.net.NetworkCapabilities;
+import android.net.NetworkInfo;
+import android.net.NetworkInfo.DetailedState;
+import android.net.RouteInfo;
+import android.net.StringNetworkSpecifier;
import android.net.TestNetworkInterface;
import android.net.util.NetdService;
+import android.os.Binder;
import android.os.Handler;
import android.os.HandlerThread;
import android.os.IBinder;
import android.os.INetworkManagementService;
-import android.util.Log;
+import android.os.Looper;
+import android.os.ParcelFileDescriptor;
+import android.os.RemoteException;
+import android.util.SparseArray;
+import com.android.internal.annotations.GuardedBy;
import com.android.internal.annotations.VisibleForTesting;
+import java.io.UncheckedIOException;
+import java.net.Inet4Address;
+import java.net.Inet6Address;
+import java.net.InterfaceAddress;
+import java.net.NetworkInterface;
+import java.net.SocketException;
+import java.util.concurrent.atomic.AtomicInteger;
+
/** @hide */
class TestNetworkService extends ITestNetworkManager.Stub {
@NonNull private static final String TAG = TestNetworkService.class.getSimpleName();
@NonNull private static final String TEST_NETWORK_TYPE = "TEST_NETWORK";
+ @NonNull private static final String TEST_TUN_PREFIX = "testtun";
+ @NonNull private static final AtomicInteger sTestTunIndex = new AtomicInteger();
@NonNull private final Context mContext;
@NonNull private final INetworkManagementService mNMS;
@@ -45,18 +69,19 @@
@NonNull private final HandlerThread mHandlerThread;
@NonNull private final Handler mHandler;
+ // Native method stubs
+ private static native int jniCreateTun(@NonNull String iface);
+
@VisibleForTesting
protected TestNetworkService(
@NonNull Context context, @NonNull INetworkManagementService netManager) {
- Log.d(TAG, "TestNetworkService starting up");
-
mHandlerThread = new HandlerThread("TestNetworkServiceThread");
mHandlerThread.start();
mHandler = new Handler(mHandlerThread.getLooper());
mContext = checkNotNull(context, "missing Context");
mNMS = checkNotNull(netManager, "missing INetworkManagementService");
- mNetd = NetdService.getInstance();
+ mNetd = checkNotNull(NetdService.getInstance(), "could not get netd instance");
}
/**
@@ -66,8 +91,167 @@
* TUN interface.
*/
@Override
- public synchronized TestNetworkInterface createTunInterface(@NonNull LinkAddress[] linkAddrs) {
- return null;
+ public TestNetworkInterface createTunInterface(@NonNull LinkAddress[] linkAddrs) {
+ enforceTestNetworkPermissions(mContext);
+
+ checkNotNull(linkAddrs, "missing linkAddrs");
+
+ String iface = TEST_TUN_PREFIX + sTestTunIndex.getAndIncrement();
+ return Binder.withCleanCallingIdentity(
+ () -> {
+ try {
+ ParcelFileDescriptor tunIntf =
+ ParcelFileDescriptor.adoptFd(jniCreateTun(iface));
+ for (LinkAddress addr : linkAddrs) {
+ mNetd.interfaceAddAddress(
+ iface,
+ addr.getAddress().getHostAddress(),
+ addr.getPrefixLength());
+ }
+
+ return new TestNetworkInterface(tunIntf, iface);
+ } catch (RemoteException e) {
+ throw e.rethrowFromSystemServer();
+ }
+ });
+ }
+
+ // Tracker for TestNetworkAgents
+ @GuardedBy("mTestNetworkTracker")
+ @NonNull
+ private final SparseArray<TestNetworkAgent> mTestNetworkTracker = new SparseArray<>();
+
+ public class TestNetworkAgent extends NetworkAgent implements IBinder.DeathRecipient {
+ private static final int NETWORK_SCORE = 1; // Use a low, non-zero score.
+
+ private final int mUid;
+ @NonNull private final NetworkInfo mNi;
+ @NonNull private final NetworkCapabilities mNc;
+ @NonNull private final LinkProperties mLp;
+
+ @GuardedBy("mBinderLock")
+ @NonNull
+ private IBinder mBinder;
+
+ @NonNull private final Object mBinderLock = new Object();
+
+ private TestNetworkAgent(
+ @NonNull Looper looper,
+ @NonNull Context context,
+ @NonNull NetworkInfo ni,
+ @NonNull NetworkCapabilities nc,
+ @NonNull LinkProperties lp,
+ int uid,
+ @NonNull IBinder binder)
+ throws RemoteException {
+ super(looper, context, TEST_NETWORK_TYPE, ni, nc, lp, NETWORK_SCORE);
+
+ mUid = uid;
+ mNi = ni;
+ mNc = nc;
+ mLp = lp;
+
+ synchronized (mBinderLock) {
+ mBinder = binder; // Binder null-checks in create()
+
+ try {
+ mBinder.linkToDeath(this, 0);
+ } catch (RemoteException e) {
+ binderDied();
+ throw e; // Abort, signal failure up the stack.
+ }
+ }
+ }
+
+ /**
+ * If the Binder object dies, this function is called to free the resources of this
+ * TestNetworkAgent
+ */
+ @Override
+ public void binderDied() {
+ teardown();
+ }
+
+ @Override
+ protected void unwanted() {
+ teardown();
+ }
+
+ private void teardown() {
+ mNi.setDetailedState(DetailedState.DISCONNECTED, null, null);
+ mNi.setIsAvailable(false);
+ sendNetworkInfo(mNi);
+
+ // Synchronize on mBinderLock to ensure that unlinkToDeath is never called more than
+ // once (otherwise it could throw an exception)
+ synchronized (mBinderLock) {
+ // If mBinder is null, this Test Network has already been cleaned up.
+ if (mBinder == null) return;
+ mBinder.unlinkToDeath(this, 0);
+ mBinder = null;
+ }
+
+ // Has to be in TestNetworkAgent to ensure all teardown codepaths properly clean up
+ // resources, even for binder death or unwanted calls.
+ synchronized (mTestNetworkTracker) {
+ mTestNetworkTracker.remove(netId);
+ }
+ }
+ }
+
+ private TestNetworkAgent registerTestNetworkAgent(
+ @NonNull Looper looper,
+ @NonNull Context context,
+ @NonNull String iface,
+ int callingUid,
+ @NonNull IBinder binder)
+ throws RemoteException, SocketException {
+ checkNotNull(looper, "missing Looper");
+ checkNotNull(context, "missing Context");
+ // iface and binder validity checked by caller
+
+ // Build network info with special testing type
+ NetworkInfo ni = new NetworkInfo(ConnectivityManager.TYPE_TEST, 0, TEST_NETWORK_TYPE, "");
+ ni.setDetailedState(DetailedState.CONNECTED, null, null);
+ ni.setIsAvailable(true);
+
+ // Build narrow set of NetworkCapabilities, useful only for testing
+ NetworkCapabilities nc = new NetworkCapabilities();
+ nc.clearAll(); // Remove default capabilities.
+ nc.addTransportType(NetworkCapabilities.TRANSPORT_TEST);
+ nc.addCapability(NetworkCapabilities.NET_CAPABILITY_NOT_SUSPENDED);
+ nc.addCapability(NetworkCapabilities.NET_CAPABILITY_NOT_RESTRICTED);
+ nc.setNetworkSpecifier(new StringNetworkSpecifier(iface));
+
+ // Build LinkProperties
+ LinkProperties lp = new LinkProperties();
+ lp.setInterfaceName(iface);
+
+ // Find the currently assigned addresses, and add them to LinkProperties
+ boolean allowIPv4 = false, allowIPv6 = false;
+ NetworkInterface netIntf = NetworkInterface.getByName(iface);
+ checkNotNull(netIntf, "No such network interface found: " + netIntf);
+
+ for (InterfaceAddress intfAddr : netIntf.getInterfaceAddresses()) {
+ lp.addLinkAddress(
+ new LinkAddress(intfAddr.getAddress(), intfAddr.getNetworkPrefixLength()));
+
+ if (intfAddr.getAddress() instanceof Inet6Address) {
+ allowIPv6 |= !intfAddr.getAddress().isLinkLocalAddress();
+ } else if (intfAddr.getAddress() instanceof Inet4Address) {
+ allowIPv4 = true;
+ }
+ }
+
+ // Add global routes (but as non-default, non-internet providing network)
+ if (allowIPv4) {
+ lp.addRoute(new RouteInfo(new IpPrefix(Inet4Address.ANY, 0), null, iface));
+ }
+ if (allowIPv6) {
+ lp.addRoute(new RouteInfo(new IpPrefix(Inet6Address.ANY, 0), null, iface));
+ }
+
+ return new TestNetworkAgent(looper, context, ni, nc, lp, callingUid, binder);
}
/**
@@ -77,9 +261,78 @@
* <p>This method provides a Network that is useful only for testing.
*/
@Override
- public synchronized void setupTestNetwork(@NonNull String iface, @NonNull IBinder binder) {}
+ public void setupTestNetwork(@NonNull String iface, @NonNull IBinder binder) {
+ enforceTestNetworkPermissions(mContext);
+
+ checkNotNull(iface, "missing Iface");
+ checkNotNull(binder, "missing IBinder");
+
+ if (!(iface.startsWith(INetd.IPSEC_INTERFACE_PREFIX)
+ || iface.startsWith(TEST_TUN_PREFIX))) {
+ throw new IllegalArgumentException(
+ "Cannot create network for non ipsec, non-testtun interface");
+ }
+
+ // Setup needs to be done with NETWORK_STACK privileges.
+ int callingUid = Binder.getCallingUid();
+ Binder.withCleanCallingIdentity(
+ () -> {
+ try {
+ mNMS.setInterfaceUp(iface);
+
+ // Synchronize all accesses to mTestNetworkTracker to prevent the case
+ // where:
+ // 1. TestNetworkAgent successfully binds to death of binder
+ // 2. Before it is added to the mTestNetworkTracker, binder dies,
+ // binderDied() is called (on a different thread)
+ // 3. This thread is pre-empted, put() is called after remove()
+ synchronized (mTestNetworkTracker) {
+ TestNetworkAgent agent =
+ registerTestNetworkAgent(
+ mHandler.getLooper(),
+ mContext,
+ iface,
+ callingUid,
+ binder);
+
+ mTestNetworkTracker.put(agent.netId, agent);
+ }
+ } catch (SocketException e) {
+ throw new UncheckedIOException(e);
+ } catch (RemoteException e) {
+ throw e.rethrowFromSystemServer();
+ }
+ });
+ }
/** Teardown a test network */
@Override
- public synchronized void teardownTestNetwork(int netId) {}
+ public void teardownTestNetwork(int netId) {
+ enforceTestNetworkPermissions(mContext);
+
+ TestNetworkAgent agent;
+ synchronized (mTestNetworkTracker) {
+ agent = mTestNetworkTracker.get(netId);
+ }
+
+ if (agent == null) {
+ return; // Already torn down
+ } else if (agent.mUid != Binder.getCallingUid()) {
+ throw new SecurityException("Attempted to modify other user's test networks");
+ }
+
+ // Safe to be called multiple times.
+ agent.teardown();
+ }
+
+ // STOPSHIP: Change this back to android.Manifest.permission.MANAGE_TEST_NETWORKS
+ private static final String PERMISSION_NAME = "dummy";
+
+ public static void enforceTestNetworkPermissions(@NonNull Context context) {
+ // STOPSHIP: Re-enable these checks. Disabled until adoptShellPermissionIdentity() can be
+ // called from CTS test code.
+ if (false) {
+ context.enforceCallingOrSelfPermission(PERMISSION_NAME, "TestNetworkService");
+ }
+ }
}
diff --git a/services/core/jni/Android.bp b/services/core/jni/Android.bp
index 6735ab4..07a6c70 100644
--- a/services/core/jni/Android.bp
+++ b/services/core/jni/Android.bp
@@ -38,6 +38,7 @@
"com_android_server_SerialService.cpp",
"com_android_server_storage_AppFuseBridge.cpp",
"com_android_server_SystemServer.cpp",
+ "com_android_server_TestNetworkService.cpp",
"com_android_server_tv_TvUinputBridge.cpp",
"com_android_server_tv_TvInputHal.cpp",
"com_android_server_vr_VrManagerService.cpp",
diff --git a/services/core/jni/com_android_server_TestNetworkService.cpp b/services/core/jni/com_android_server_TestNetworkService.cpp
new file mode 100644
index 0000000..b90ff23
--- /dev/null
+++ b/services/core/jni/com_android_server_TestNetworkService.cpp
@@ -0,0 +1,107 @@
+/*
+ * Copyright (C) 2018 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.
+ */
+
+#define LOG_NDEBUG 0
+
+#define LOG_TAG "TestNetworkServiceJni"
+
+#include <arpa/inet.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <linux/if.h>
+#include <linux/if_tun.h>
+#include <linux/ipv6_route.h>
+#include <linux/route.h>
+#include <netinet/in.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include <log/log.h>
+
+#include "netutils/ifc.h"
+
+#include "jni.h"
+#include <android-base/stringprintf.h>
+#include <android-base/unique_fd.h>
+#include <nativehelper/JNIHelp.h>
+#include <nativehelper/ScopedUtfChars.h>
+
+namespace android {
+
+//------------------------------------------------------------------------------
+
+static void throwException(JNIEnv* env, int error, const char* action, const char* iface) {
+ const std::string& msg =
+ android::base::StringPrintf("Error %s %s: %s", action, iface, strerror(error));
+
+ jniThrowException(env, "java/lang/IllegalStateException", msg.c_str());
+}
+
+static int createTunInterface(JNIEnv* env, const char* iface) {
+ base::unique_fd tun(open("/dev/tun", O_RDWR | O_NONBLOCK));
+ ifreq ifr{};
+
+ // Allocate interface.
+ ifr.ifr_flags = IFF_TUN | IFF_NO_PI;
+ strlcpy(ifr.ifr_name, iface, IFNAMSIZ);
+ if (ioctl(tun.get(), TUNSETIFF, &ifr)) {
+ throwException(env, errno, "allocating", ifr.ifr_name);
+ return -1;
+ }
+
+ // Activate interface using an unconnected datagram socket.
+ base::unique_fd inet6CtrlSock(socket(AF_INET6, SOCK_DGRAM, 0));
+ ifr.ifr_flags = IFF_UP;
+
+ if (ioctl(inet6CtrlSock.get(), SIOCSIFFLAGS, &ifr)) {
+ throwException(env, errno, "activating", ifr.ifr_name);
+ return -1;
+ }
+
+ return tun.release();
+}
+
+//------------------------------------------------------------------------------
+
+static jint create(JNIEnv* env, jobject /* thiz */, jstring jIface) {
+ ScopedUtfChars iface(env, jIface);
+ if (!iface.c_str()) {
+ jniThrowNullPointerException(env, "iface");
+ return -1;
+ }
+
+ int tun = createTunInterface(env, iface.c_str());
+
+ // Any exceptions will be thrown from the createTunInterface call
+ return tun;
+}
+
+//------------------------------------------------------------------------------
+
+static const JNINativeMethod gMethods[] = {
+ {"jniCreateTun", "(Ljava/lang/String;)I", (void*)create},
+};
+
+int register_android_server_TestNetworkService(JNIEnv* env) {
+ return jniRegisterNativeMethods(env, "com/android/server/TestNetworkService", gMethods,
+ NELEM(gMethods));
+}
+
+}; // namespace android
diff --git a/services/core/jni/onload.cpp b/services/core/jni/onload.cpp
index bb6e684..83347bb 100644
--- a/services/core/jni/onload.cpp
+++ b/services/core/jni/onload.cpp
@@ -43,6 +43,7 @@
int register_android_server_location_GnssLocationProvider(JNIEnv* env);
int register_android_server_connectivity_Vpn(JNIEnv* env);
int register_android_server_connectivity_tethering_OffloadHardwareInterface(JNIEnv*);
+int register_android_server_TestNetworkService(JNIEnv* env);
int register_android_server_devicepolicy_CryptoTestHelper(JNIEnv*);
int register_android_server_hdmi_HdmiCecController(JNIEnv* env);
int register_android_server_tv_TvUinputBridge(JNIEnv* env);
@@ -88,6 +89,7 @@
register_android_server_location_GnssLocationProvider(env);
register_android_server_connectivity_Vpn(env);
register_android_server_connectivity_tethering_OffloadHardwareInterface(env);
+ register_android_server_TestNetworkService(env);
register_android_server_devicepolicy_CryptoTestHelper(env);
register_android_server_ConsumerIrService(env);
register_android_server_BatteryStatsService(env);