Merge "tethering: offload: Netlink Req" into rvc-dev am: 0de458a8

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/11970745

Change-Id: I14944e318cea5792941dcf2cf14c12ff468a846c

Tethering/src/com/android/networkstack/tethering/OffloadHardwareInterface.java

@@ -16,8 +16,11 @@
 
 package com.android.networkstack.tethering;
 
+import static android.net.netlink.StructNlMsgHdr.NLM_F_DUMP;
+import static android.net.netlink.StructNlMsgHdr.NLM_F_REQUEST;
 import static android.net.util.TetheringUtils.uint16;
 
+import android.annotation.NonNull;
 import android.hardware.tetheroffload.config.V1_0.IOffloadConfig;
 import android.hardware.tetheroffload.control.V1_0.IOffloadControl;
 import android.hardware.tetheroffload.control.V1_0.ITetheringOffloadCallback;
@@ -25,6 +28,7 @@ import android.hardware.tetheroffload.control.V1_0.NatTimeoutUpdate;
 import android.hardware.tetheroffload.control.V1_0.NetworkProtocol;
 import android.hardware.tetheroffload.control.V1_0.OffloadCallbackEvent;
 import android.net.netlink.NetlinkSocket;
+import android.net.netlink.StructNlMsgHdr;
 import android.net.util.SharedLog;
 import android.net.util.SocketUtils;
 import android.os.Handler;
@@ -37,9 +41,11 @@ import android.system.OsConstants;
 import com.android.internal.annotations.VisibleForTesting;
 
 import java.io.FileDescriptor;
+import java.io.InterruptedIOException;
 import java.io.IOException;
 import java.net.SocketAddress;
 import java.net.SocketException;
+import java.nio.ByteBuffer;
 import java.util.ArrayList;
 import java.util.NoSuchElementException;
 
@@ -63,6 +69,11 @@ public class OffloadHardwareInterface {
     private static final int NF_NETLINK_CONNTRACK_NEW = 1;
     private static final int NF_NETLINK_CONNTRACK_UPDATE = 2;
     private static final int NF_NETLINK_CONNTRACK_DESTROY = 4;
+    // Reference libnetfilter_conntrack/linux_nfnetlink_conntrack.h
+    public static final short NFNL_SUBSYS_CTNETLINK = 1;
+    public static final short IPCTNL_MSG_CT_GET = 1;
+
+    private final long NETLINK_MESSAGE_TIMEOUT_MS = 500;
 
     private final Handler mHandler;
     private final SharedLog mLog;
@@ -226,6 +237,9 @@ public class OffloadHardwareInterface {
                 NF_NETLINK_CONNTRACK_NEW | NF_NETLINK_CONNTRACK_DESTROY);
         if (h1 == null) return false;
 
+        sendNetlinkMessage(h1, (short) ((NFNL_SUBSYS_CTNETLINK << 8) | IPCTNL_MSG_CT_GET),
+                           (short) (NLM_F_REQUEST | NLM_F_DUMP));
+
         final NativeHandle h2 = mDeps.createConntrackSocket(
                 NF_NETLINK_CONNTRACK_UPDATE | NF_NETLINK_CONNTRACK_DESTROY);
         if (h2 == null) {
@@ -252,6 +266,25 @@ public class OffloadHardwareInterface {
         return results.mSuccess;
     }
 
+    @VisibleForTesting
+    public void sendNetlinkMessage(@NonNull NativeHandle handle, short type, short flags) {
+        final int length = StructNlMsgHdr.STRUCT_SIZE;
+        final byte[] msg = new byte[length];
+        final StructNlMsgHdr nlh = new StructNlMsgHdr();
+        final ByteBuffer byteBuffer = ByteBuffer.wrap(msg);
+        nlh.nlmsg_len = length;
+        nlh.nlmsg_type = type;
+        nlh.nlmsg_flags = flags;
+        nlh.nlmsg_seq = 1;
+        nlh.pack(byteBuffer);
+        try {
+            NetlinkSocket.sendMessage(handle.getFileDescriptor(), msg, 0 /* offset */, length,
+                                      NETLINK_MESSAGE_TIMEOUT_MS);
+        } catch (ErrnoException | InterruptedIOException e) {
+            mLog.e("Unable to send netfilter message, error: " + e);
+        }
+    }
+
     private void closeFdInNativeHandle(final NativeHandle h) {
         try {
             h.close();

Tethering/tests/unit/src/com/android/networkstack/tethering/OffloadHardwareInterfaceTest.java

@@ -17,13 +17,17 @@
 package com.android.networkstack.tethering;
 
 import static android.net.util.TetheringUtils.uint16;
+import static android.system.OsConstants.SOCK_STREAM;
+import static android.system.OsConstants.AF_UNIX;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.fail;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.spy;
 import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
 
 import android.hardware.tetheroffload.config.V1_0.IOffloadConfig;
 import android.hardware.tetheroffload.control.V1_0.IOffloadControl;
@@ -31,11 +35,14 @@ import android.hardware.tetheroffload.control.V1_0.ITetheringOffloadCallback;
 import android.hardware.tetheroffload.control.V1_0.NatTimeoutUpdate;
 import android.hardware.tetheroffload.control.V1_0.NetworkProtocol;
 import android.hardware.tetheroffload.control.V1_0.OffloadCallbackEvent;
+import android.net.netlink.StructNlMsgHdr;
 import android.net.util.SharedLog;
 import android.os.Handler;
 import android.os.NativeHandle;
 import android.os.test.TestLooper;
+import android.system.ErrnoException;
 import android.system.OsConstants;
+import android.system.Os;
 
 import androidx.test.filters.SmallTest;
 import androidx.test.runner.AndroidJUnit4;
@@ -47,6 +54,9 @@ import org.mockito.ArgumentCaptor;
 import org.mockito.Mock;
 import org.mockito.MockitoAnnotations;
 
+import java.io.FileDescriptor;
+import java.io.OutputStream;
+import java.nio.ByteBuffer;
 import java.util.ArrayList;
 
 @RunWith(AndroidJUnit4.class)
@@ -64,6 +74,10 @@ public final class OffloadHardwareInterfaceTest {
     @Mock private IOffloadControl mIOffloadControl;
     @Mock private NativeHandle mNativeHandle;
 
+    // Random values to test Netlink message.
+    private static final short TEST_TYPE = 184;
+    private static final short TEST_FLAGS = 263;
+
     class MyDependencies extends OffloadHardwareInterface.Dependencies {
         MyDependencies(SharedLog log) {
             super(log);
@@ -203,6 +217,31 @@ public final class OffloadHardwareInterfaceTest {
                 eq(uint16(udpParams.dst.port)));
     }
 
+    @Test
+    public void testNetlinkMessage() throws Exception {
+        FileDescriptor writeSocket = new FileDescriptor();
+        FileDescriptor readSocket = new FileDescriptor();
+        try {
+            Os.socketpair(AF_UNIX, SOCK_STREAM, 0, writeSocket, readSocket);
+        } catch (ErrnoException e) {
+            fail();
+            return;
+        }
+        when(mNativeHandle.getFileDescriptor()).thenReturn(writeSocket);
+
+        mOffloadHw.sendNetlinkMessage(mNativeHandle, TEST_TYPE, TEST_FLAGS);
+
+        ByteBuffer buffer = ByteBuffer.allocate(StructNlMsgHdr.STRUCT_SIZE);
+        int read = Os.read(readSocket, buffer);
+
+        buffer.flip();
+        assertEquals(StructNlMsgHdr.STRUCT_SIZE, buffer.getInt());
+        assertEquals(TEST_TYPE, buffer.getShort());
+        assertEquals(TEST_FLAGS, buffer.getShort());
+        assertEquals(1 /* seq */, buffer.getInt());
+        assertEquals(0 /* pid */, buffer.getInt());
+    }
+
     private NatTimeoutUpdate buildNatTimeoutUpdate(final int proto) {
         final NatTimeoutUpdate params = new NatTimeoutUpdate();
         params.proto = proto;