2 * Copyright (C) 2014 The Android Open Source Project
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
8 * http://www.apache.org/licenses/LICENSE-2.0
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.
19 import android.content.Context;
20 import android.os.Bundle;
21 import android.os.Handler;
22 import android.os.Looper;
23 import android.os.Message;
24 import android.os.Messenger;
25 import android.util.Log;
27 import com.android.internal.util.AsyncChannel;
28 import com.android.internal.util.Protocol;
29 import android.net.ConnectivityManager.PacketKeepalive;
31 import java.util.ArrayList;
32 import java.util.concurrent.atomic.AtomicBoolean;
35 * A Utility class for handling for communicating between bearer-specific
36 * code and ConnectivityService.
38 * A bearer may have more than one NetworkAgent if it can simultaneously
39 * support separate networks (IMS / Internet / MMS Apns on cellular, or
40 * perhaps connections with different SSID or P2P for Wi-Fi).
44 public abstract class NetworkAgent extends Handler {
45 // Guaranteed to be valid (not NETID_UNSET), otherwise registerNetworkAgent() would have thrown
47 public final int netId;
49 private volatile AsyncChannel mAsyncChannel;
50 private final String LOG_TAG;
51 private static final boolean DBG = true;
52 private static final boolean VDBG = false;
53 private final Context mContext;
54 private final ArrayList<Message>mPreConnectedQueue = new ArrayList<Message>();
55 private volatile long mLastBwRefreshTime = 0;
56 private static final long BW_REFRESH_MIN_WIN_MS = 500;
57 private boolean mPollLceScheduled = false;
58 private AtomicBoolean mPollLcePending = new AtomicBoolean(false);
60 private static final int BASE = Protocol.BASE_NETWORK_AGENT;
63 * Sent by ConnectivityService to the NetworkAgent to inform it of
64 * suspected connectivity problems on its network. The NetworkAgent
65 * should take steps to verify and correct connectivity.
67 public static final int CMD_SUSPECT_BAD = BASE;
70 * Sent by the NetworkAgent (note the EVENT vs CMD prefix) to
71 * ConnectivityService to pass the current NetworkInfo (connection state).
72 * Sent when the NetworkInfo changes, mainly due to change of state.
75 public static final int EVENT_NETWORK_INFO_CHANGED = BASE + 1;
78 * Sent by the NetworkAgent to ConnectivityService to pass the current
80 * obj = NetworkCapabilities
82 public static final int EVENT_NETWORK_CAPABILITIES_CHANGED = BASE + 2;
85 * Sent by the NetworkAgent to ConnectivityService to pass the current
87 * obj = NetworkProperties
89 public static final int EVENT_NETWORK_PROPERTIES_CHANGED = BASE + 3;
91 /* centralize place where base network score, and network score scaling, will be
92 * stored, so as we can consistently compare apple and oranges, or wifi, ethernet and LTE
94 public static final int WIFI_BASE_SCORE = 60;
97 * Sent by the NetworkAgent to ConnectivityService to pass the current
99 * obj = network score Integer
101 public static final int EVENT_NETWORK_SCORE_CHANGED = BASE + 4;
104 * Sent by the NetworkAgent to ConnectivityService to add new UID ranges
105 * to be forced into this Network. For VPNs only.
106 * obj = UidRange[] to forward
108 public static final int EVENT_UID_RANGES_ADDED = BASE + 5;
111 * Sent by the NetworkAgent to ConnectivityService to remove UID ranges
112 * from being forced into this Network. For VPNs only.
113 * obj = UidRange[] to stop forwarding
115 public static final int EVENT_UID_RANGES_REMOVED = BASE + 6;
118 * Sent by ConnectivityService to the NetworkAgent to inform the agent of the
119 * networks status - whether we could use the network or could not, due to
120 * either a bad network configuration (no internet link) or captive portal.
122 * arg1 = either {@code VALID_NETWORK} or {@code INVALID_NETWORK}
123 * obj = Bundle containing map from {@code REDIRECT_URL_KEY} to {@code String}
124 * representing URL that Internet probe was redirect to, if it was redirected,
125 * or mapping to {@code null} otherwise.
127 public static final int CMD_REPORT_NETWORK_STATUS = BASE + 7;
129 public static final int VALID_NETWORK = 1;
130 public static final int INVALID_NETWORK = 2;
132 public static String REDIRECT_URL_KEY = "redirect URL";
135 * Sent by the NetworkAgent to ConnectivityService to indicate this network was
136 * explicitly selected. This should be sent before the NetworkInfo is marked
137 * CONNECTED so it can be given special treatment at that time.
139 * obj = boolean indicating whether to use this network even if unvalidated
141 public static final int EVENT_SET_EXPLICITLY_SELECTED = BASE + 8;
144 * Sent by ConnectivityService to the NetworkAgent to inform the agent of
145 * whether the network should in the future be used even if not validated.
146 * This decision is made by the user, but it is the network transport's
147 * responsibility to remember it.
149 * arg1 = 1 if true, 0 if false
151 public static final int CMD_SAVE_ACCEPT_UNVALIDATED = BASE + 9;
154 * Sent by ConnectivityService to the NetworkAgent to inform the agent to pull
155 * the underlying network connection for updated bandwidth information.
157 public static final int CMD_REQUEST_BANDWIDTH_UPDATE = BASE + 10;
160 * Sent by ConnectivityService to the NetworkAgent to request that the specified packet be sent
161 * periodically on the given interval.
163 * arg1 = the slot number of the keepalive to start
164 * arg2 = interval in seconds
165 * obj = KeepalivePacketData object describing the data to be sent
167 * Also used internally by ConnectivityService / KeepaliveTracker, with different semantics.
169 public static final int CMD_START_PACKET_KEEPALIVE = BASE + 11;
172 * Requests that the specified keepalive packet be stopped.
174 * arg1 = slot number of the keepalive to stop.
176 * Also used internally by ConnectivityService / KeepaliveTracker, with different semantics.
178 public static final int CMD_STOP_PACKET_KEEPALIVE = BASE + 12;
181 * Sent by the NetworkAgent to ConnectivityService to provide status on a packet keepalive
182 * request. This may either be the reply to a CMD_START_PACKET_KEEPALIVE, or an asynchronous
183 * error notification.
185 * This is also sent by KeepaliveTracker to the app's ConnectivityManager.PacketKeepalive to
186 * so that the app's PacketKeepaliveCallback methods can be called.
188 * arg1 = slot number of the keepalive
191 public static final int EVENT_PACKET_KEEPALIVE = BASE + 13;
194 * Sent by ConnectivityService to inform this network transport of signal strength thresholds
195 * that when crossed should trigger a system wakeup and a NetworkCapabilities update.
197 * obj = int[] describing signal strength thresholds.
199 public static final int CMD_SET_SIGNAL_STRENGTH_THRESHOLDS = BASE + 14;
202 * Sent by ConnectivityService to the NeworkAgent to inform the agent to avoid
203 * automatically reconnecting to this network (e.g. via autojoin). Happens
204 * when user selects "No" option on the "Stay connected?" dialog box.
206 public static final int CMD_PREVENT_AUTOMATIC_RECONNECT = BASE + 15;
208 public NetworkAgent(Looper looper, Context context, String logTag, NetworkInfo ni,
209 NetworkCapabilities nc, LinkProperties lp, int score) {
210 this(looper, context, logTag, ni, nc, lp, score, null);
213 public NetworkAgent(Looper looper, Context context, String logTag, NetworkInfo ni,
214 NetworkCapabilities nc, LinkProperties lp, int score, NetworkMisc misc) {
218 if (ni == null || nc == null || lp == null) {
219 throw new IllegalArgumentException();
222 if (VDBG) log("Registering NetworkAgent");
223 ConnectivityManager cm = (ConnectivityManager)mContext.getSystemService(
224 Context.CONNECTIVITY_SERVICE);
225 netId = cm.registerNetworkAgent(new Messenger(this), new NetworkInfo(ni),
226 new LinkProperties(lp), new NetworkCapabilities(nc), score, misc);
230 public void handleMessage(Message msg) {
232 case AsyncChannel.CMD_CHANNEL_FULL_CONNECTION: {
233 if (mAsyncChannel != null) {
234 log("Received new connection while already connected!");
236 if (VDBG) log("NetworkAgent fully connected");
237 AsyncChannel ac = new AsyncChannel();
238 ac.connected(null, this, msg.replyTo);
239 ac.replyToMessage(msg, AsyncChannel.CMD_CHANNEL_FULLY_CONNECTED,
240 AsyncChannel.STATUS_SUCCESSFUL);
241 synchronized (mPreConnectedQueue) {
243 for (Message m : mPreConnectedQueue) {
246 mPreConnectedQueue.clear();
251 case AsyncChannel.CMD_CHANNEL_DISCONNECT: {
252 if (VDBG) log("CMD_CHANNEL_DISCONNECT");
253 if (mAsyncChannel != null) mAsyncChannel.disconnect();
256 case AsyncChannel.CMD_CHANNEL_DISCONNECTED: {
257 if (DBG) log("NetworkAgent channel lost");
258 // let the client know CS is done with us.
260 synchronized (mPreConnectedQueue) {
261 mAsyncChannel = null;
265 case CMD_SUSPECT_BAD: {
266 log("Unhandled Message " + msg);
269 case CMD_REQUEST_BANDWIDTH_UPDATE: {
270 long currentTimeMs = System.currentTimeMillis();
272 log("CMD_REQUEST_BANDWIDTH_UPDATE request received.");
274 if (currentTimeMs >= (mLastBwRefreshTime + BW_REFRESH_MIN_WIN_MS)) {
275 mPollLceScheduled = false;
276 if (mPollLcePending.getAndSet(true) == false) {
280 // deliver the request at a later time rather than discard it completely.
281 if (!mPollLceScheduled) {
282 long waitTime = mLastBwRefreshTime + BW_REFRESH_MIN_WIN_MS -
284 mPollLceScheduled = sendEmptyMessageDelayed(
285 CMD_REQUEST_BANDWIDTH_UPDATE, waitTime);
290 case CMD_REPORT_NETWORK_STATUS: {
291 String redirectUrl = ((Bundle)msg.obj).getString(REDIRECT_URL_KEY);
293 log("CMD_REPORT_NETWORK_STATUS(" +
294 (msg.arg1 == VALID_NETWORK ? "VALID, " : "INVALID, ") + redirectUrl);
296 networkStatus(msg.arg1, redirectUrl);
299 case CMD_SAVE_ACCEPT_UNVALIDATED: {
300 saveAcceptUnvalidated(msg.arg1 != 0);
303 case CMD_START_PACKET_KEEPALIVE: {
304 startPacketKeepalive(msg);
307 case CMD_STOP_PACKET_KEEPALIVE: {
308 stopPacketKeepalive(msg);
312 case CMD_SET_SIGNAL_STRENGTH_THRESHOLDS: {
313 ArrayList<Integer> thresholds =
314 ((Bundle) msg.obj).getIntegerArrayList("thresholds");
315 // TODO: Change signal strength thresholds API to use an ArrayList<Integer>
316 // rather than convert to int[].
317 int[] intThresholds = new int[(thresholds != null) ? thresholds.size() : 0];
318 for (int i = 0; i < intThresholds.length; i++) {
319 intThresholds[i] = thresholds.get(i);
321 setSignalStrengthThresholds(intThresholds);
324 case CMD_PREVENT_AUTOMATIC_RECONNECT: {
325 preventAutomaticReconnect();
331 private void queueOrSendMessage(int what, Object obj) {
332 queueOrSendMessage(what, 0, 0, obj);
335 private void queueOrSendMessage(int what, int arg1, int arg2) {
336 queueOrSendMessage(what, arg1, arg2, null);
339 private void queueOrSendMessage(int what, int arg1, int arg2, Object obj) {
340 Message msg = Message.obtain();
345 queueOrSendMessage(msg);
348 private void queueOrSendMessage(Message msg) {
349 synchronized (mPreConnectedQueue) {
350 if (mAsyncChannel != null) {
351 mAsyncChannel.sendMessage(msg);
353 mPreConnectedQueue.add(msg);
359 * Called by the bearer code when it has new LinkProperties data.
361 public void sendLinkProperties(LinkProperties linkProperties) {
362 queueOrSendMessage(EVENT_NETWORK_PROPERTIES_CHANGED, new LinkProperties(linkProperties));
366 * Called by the bearer code when it has new NetworkInfo data.
368 public void sendNetworkInfo(NetworkInfo networkInfo) {
369 queueOrSendMessage(EVENT_NETWORK_INFO_CHANGED, new NetworkInfo(networkInfo));
373 * Called by the bearer code when it has new NetworkCapabilities data.
375 public void sendNetworkCapabilities(NetworkCapabilities networkCapabilities) {
376 mPollLcePending.set(false);
377 mLastBwRefreshTime = System.currentTimeMillis();
378 queueOrSendMessage(EVENT_NETWORK_CAPABILITIES_CHANGED,
379 new NetworkCapabilities(networkCapabilities));
383 * Called by the bearer code when it has a new score for this network.
385 public void sendNetworkScore(int score) {
387 throw new IllegalArgumentException("Score must be >= 0");
389 queueOrSendMessage(EVENT_NETWORK_SCORE_CHANGED, new Integer(score));
393 * Called by the VPN code when it wants to add ranges of UIDs to be routed
394 * through the VPN network.
396 public void addUidRanges(UidRange[] ranges) {
397 queueOrSendMessage(EVENT_UID_RANGES_ADDED, ranges);
401 * Called by the VPN code when it wants to remove ranges of UIDs from being routed
402 * through the VPN network.
404 public void removeUidRanges(UidRange[] ranges) {
405 queueOrSendMessage(EVENT_UID_RANGES_REMOVED, ranges);
409 * Called by the bearer to indicate this network was manually selected by the user.
410 * This should be called before the NetworkInfo is marked CONNECTED so that this
411 * Network can be given special treatment at that time. If {@code acceptUnvalidated} is
412 * {@code true}, then the system will switch to this network. If it is {@code false} and the
413 * network cannot be validated, the system will ask the user whether to switch to this network.
414 * If the user confirms and selects "don't ask again", then the system will call
415 * {@link #saveAcceptUnvalidated} to persist the user's choice. Thus, if the transport ever
416 * calls this method with {@code acceptUnvalidated} set to {@code false}, it must also implement
417 * {@link #saveAcceptUnvalidated} to respect the user's choice.
419 public void explicitlySelected(boolean acceptUnvalidated) {
420 queueOrSendMessage(EVENT_SET_EXPLICITLY_SELECTED, acceptUnvalidated);
424 * Called when ConnectivityService has indicated they no longer want this network.
425 * The parent factory should (previously) have received indication of the change
426 * as well, either canceling NetworkRequests or altering their score such that this
427 * network won't be immediately requested again.
429 abstract protected void unwanted();
432 * Called when ConnectivityService request a bandwidth update. The parent factory
433 * shall try to overwrite this method and produce a bandwidth update if capable.
435 protected void pollLceData() {
439 * Called when the system determines the usefulness of this network.
441 * Networks claiming internet connectivity will have their internet
442 * connectivity verified.
444 * Currently there are two possible values:
445 * {@code VALID_NETWORK} if the system is happy with the connection,
446 * {@code INVALID_NETWORK} if the system is not happy.
447 * TODO - add indications of captive portal-ness and related success/failure,
448 * ie, CAPTIVE_SUCCESS_NETWORK, CAPTIVE_NETWORK for successful login and detection
450 * This may be called multiple times as the network status changes and may
451 * generate false negatives if we lose ip connectivity before the link is torn down.
453 * @param status one of {@code VALID_NETWORK} or {@code INVALID_NETWORK}.
454 * @param redirectUrl If the Internet probe was redirected, this is the destination it was
455 * redirected to, otherwise {@code null}.
457 protected void networkStatus(int status, String redirectUrl) {
461 * Called when the user asks to remember the choice to use this network even if unvalidated.
462 * The transport is responsible for remembering the choice, and the next time the user connects
463 * to the network, should explicitlySelected with {@code acceptUnvalidated} set to {@code true}.
464 * This method will only be called if {@link #explicitlySelected} was called with
465 * {@code acceptUnvalidated} set to {@code false}.
467 protected void saveAcceptUnvalidated(boolean accept) {
471 * Requests that the network hardware send the specified packet at the specified interval.
473 protected void startPacketKeepalive(Message msg) {
474 onPacketKeepaliveEvent(msg.arg1, PacketKeepalive.ERROR_HARDWARE_UNSUPPORTED);
478 * Requests that the network hardware send the specified packet at the specified interval.
480 protected void stopPacketKeepalive(Message msg) {
481 onPacketKeepaliveEvent(msg.arg1, PacketKeepalive.ERROR_HARDWARE_UNSUPPORTED);
485 * Called by the network when a packet keepalive event occurs.
487 public void onPacketKeepaliveEvent(int slot, int reason) {
488 queueOrSendMessage(EVENT_PACKET_KEEPALIVE, slot, reason);
492 * Called by ConnectivityService to inform this network transport of signal strength thresholds
493 * that when crossed should trigger a system wakeup and a NetworkCapabilities update.
495 protected void setSignalStrengthThresholds(int[] thresholds) {
499 * Called when the user asks to not stay connected to this network because it was found to not
500 * provide Internet access. Usually followed by call to {@code unwanted}. The transport is
501 * responsible for making sure the device does not automatically reconnect to the same network
502 * after the {@code unwanted} call.
504 protected void preventAutomaticReconnect() {
507 protected void log(String s) {
508 Log.d(LOG_TAG, "NetworkAgent: " + s);