/*
* Copyright (C) 2014 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.server.ethernet;
import android.content.Context;
import android.net.ConnectivityManager;
import android.net.DhcpResults;
import android.net.EthernetManager;
import android.net.IEthernetServiceListener;
import android.net.InterfaceConfiguration;
import android.net.IpConfiguration;
import android.net.IpConfiguration.IpAssignment;
import android.net.IpConfiguration.ProxySettings;
import android.net.LinkProperties;
import android.net.NetworkAgent;
import android.net.NetworkCapabilities;
import android.net.NetworkFactory;
import android.net.NetworkInfo;
import android.net.NetworkInfo.DetailedState;
import android.net.NetworkUtils;
import android.net.StaticIpConfiguration;
import android.os.Handler;
import android.os.IBinder;
import android.os.INetworkManagementService;
import android.os.Looper;
import android.os.RemoteCallbackList;
import android.os.RemoteException;
import android.os.ServiceManager;
import android.text.TextUtils;
import android.util.Log;
import com.android.internal.util.IndentingPrintWriter;
import com.android.server.net.BaseNetworkObserver;
import java.io.FileDescriptor;
import java.io.PrintWriter;
/**
* Manages connectivity for an Ethernet interface.
*
* Ethernet Interfaces may be present at boot time or appear after boot (e.g.,
* for Ethernet adapters connected over USB). This class currently supports
* only one interface. When an interface appears on the system (or is present
* at boot time) this class will start tracking it and bring it up, and will
* attempt to connect when requested. Any other interfaces that subsequently
* appear will be ignored until the tracked interface disappears. Only
* interfaces whose names match the <code>config_ethernet_iface_regex</code>
* regular expression are tracked.
*
* This class reports a static network score of 70 when it is tracking an
* interface and that interface's link is up, and a score of 0 otherwise.
*
* @hide
*/
class EthernetNetworkFactory {
private static final String NETWORK_TYPE = "Ethernet";
private static final String TAG = "EthernetNetworkFactory";
private static final int NETWORK_SCORE = 70;
private static final boolean DBG = true;
/** Tracks interface changes. Called from NetworkManagementService. */
private InterfaceObserver mInterfaceObserver;
/** For static IP configuration */
private EthernetManager mEthernetManager;
/** To set link state and configure IP addresses. */
private INetworkManagementService mNMService;
/* To communicate with ConnectivityManager */
private NetworkCapabilities mNetworkCapabilities;
private NetworkAgent mNetworkAgent;
private LocalNetworkFactory mFactory;
private Context mContext;
/** Product-dependent regular expression of interface names we track. */
private static String mIfaceMatch = "";
/** To notify Ethernet status. */
private final RemoteCallbackList<IEthernetServiceListener> mListeners;
/** Data members. All accesses to these must be synchronized(this). */
private static String mIface = "";
private String mHwAddr;
private static boolean mLinkUp;
private NetworkInfo mNetworkInfo;
private LinkProperties mLinkProperties;
EthernetNetworkFactory(RemoteCallbackList<IEthernetServiceListener> listeners) {
mNetworkInfo = new NetworkInfo(ConnectivityManager.TYPE_ETHERNET, 0, NETWORK_TYPE, "");
mLinkProperties = new LinkProperties();
initNetworkCapabilities();
mListeners = listeners;
}
private class LocalNetworkFactory extends NetworkFactory {
LocalNetworkFactory(String name, Context context, Looper looper) {
super(looper, context, name, new NetworkCapabilities());
}
protected void startNetwork() {
onRequestNetwork();
}
protected void stopNetwork() {
}
}
/**
* Updates interface state variables.
* Called on link state changes or on startup.
*/
private void updateInterfaceState(String iface, boolean up) {
if (!mIface.equals(iface)) {
return;
}
Log.d(TAG, "updateInterface: " + iface + " link " + (up ? "up" : "down"));
synchronized(this) {
mLinkUp = up;
mNetworkInfo.setIsAvailable(up);
if (!up) {
// Tell the agent we're disconnected. It will call disconnect().
mNetworkInfo.setDetailedState(DetailedState.DISCONNECTED, null, mHwAddr);
}
updateAgent();
// set our score lower than any network could go
// so we get dropped. TODO - just unregister the factory
// when link goes down.
mFactory.setScoreFilter(up ? NETWORK_SCORE : -1);
}
}
private class InterfaceObserver extends BaseNetworkObserver {
@Override
public void interfaceLinkStateChanged(String iface, boolean up) {
updateInterfaceState(iface, up);
}
@Override
public void interfaceAdded(String iface) {
maybeTrackInterface(iface);
}
@Override
public void interfaceRemoved(String iface) {
stopTrackingInterface(iface);
}
}
private void setInterfaceUp(String iface) {
// Bring up the interface so we get link status indications.
try {
NetworkUtils.stopDhcp(iface);
mNMService.setInterfaceUp(iface);
String hwAddr = null;
InterfaceConfiguration config = mNMService.getInterfaceConfig(iface);
if (config == null) {
Log.e(TAG, "Null iterface config for " + iface + ". Bailing out.");
return;
}
synchronized (this) {
if (!isTrackingInterface()) {
setInterfaceInfoLocked(iface, config.getHardwareAddress());
mNetworkInfo.setIsAvailable(true);
mNetworkInfo.setExtraInfo(mHwAddr);
} else {
Log.e(TAG, "Interface unexpectedly changed from " + iface + " to " + mIface);
mNMService.setInterfaceDown(iface);
}
}
} catch (RemoteException e) {
Log.e(TAG, "Error upping interface " + mIface + ": " + e);
}
}
private boolean maybeTrackInterface(String iface) {
// If we don't already have an interface, and if this interface matches
// our regex, start tracking it.
if (!iface.matches(mIfaceMatch) || isTrackingInterface())
return false;
Log.d(TAG, "Started tracking interface " + iface);
setInterfaceUp(iface);
return true;
}
private void stopTrackingInterface(String iface) {
if (!iface.equals(mIface))
return;
Log.d(TAG, "Stopped tracking interface " + iface);
// TODO: Unify this codepath with stop().
synchronized (this) {
NetworkUtils.stopDhcp(mIface);
setInterfaceInfoLocked("", null);
mNetworkInfo.setExtraInfo(null);
mLinkUp = false;
mNetworkInfo.setDetailedState(DetailedState.DISCONNECTED, null, mHwAddr);
updateAgent();
mNetworkAgent = null;
mNetworkInfo = new NetworkInfo(ConnectivityManager.TYPE_ETHERNET, 0, NETWORK_TYPE, "");
mLinkProperties = new LinkProperties();
}
}
private boolean setStaticIpAddress(StaticIpConfiguration staticConfig) {
if (staticConfig.ipAddress != null &&
staticConfig.gateway != null &&
staticConfig.dnsServers.size() > 0) {
try {
Log.i(TAG, "Applying static IPv4 configuration to " + mIface + ": " + staticConfig);
InterfaceConfiguration config = mNMService.getInterfaceConfig(mIface);
config.setLinkAddress(staticConfig.ipAddress);
mNMService.setInterfaceConfig(mIface, config);
return true;
} catch(RemoteException|IllegalStateException e) {
Log.e(TAG, "Setting static IP address failed: " + e.getMessage());
}
} else {
Log.e(TAG, "Invalid static IP configuration.");
}
return false;
}
public void updateAgent() {
synchronized (EthernetNetworkFactory.this) {
if (mNetworkAgent == null) return;
if (DBG) {
Log.i(TAG, "Updating mNetworkAgent with: " +
mNetworkCapabilities + ", " +
mNetworkInfo + ", " +
mLinkProperties);
}
mNetworkAgent.sendNetworkCapabilities(mNetworkCapabilities);
mNetworkAgent.sendNetworkInfo(mNetworkInfo);
mNetworkAgent.sendLinkProperties(mLinkProperties);
// never set the network score below 0.
mNetworkAgent.sendNetworkScore(mLinkUp? NETWORK_SCORE : 0);
}
}
/* Called by the NetworkFactory on the handler thread. */
public void onRequestNetwork() {
// TODO: Handle DHCP renew.
Thread dhcpThread = new Thread(new Runnable() {
public void run() {
if (DBG) Log.i(TAG, "dhcpThread(" + mIface + "): mNetworkInfo=" + mNetworkInfo);
LinkProperties linkProperties;
IpConfiguration config = mEthernetManager.getConfiguration();
if (config.getIpAssignment() == IpAssignment.STATIC) {
if (!setStaticIpAddress(config.getStaticIpConfiguration())) {
// We've already logged an error.
return;
}
linkProperties = config.getStaticIpConfiguration().toLinkProperties(mIface);
} else {
mNetworkInfo.setDetailedState(DetailedState.OBTAINING_IPADDR, null, mHwAddr);
DhcpResults dhcpResults = new DhcpResults();
// TODO: Handle DHCP renewals better.
// In general runDhcp handles DHCP renewals for us, because
// the dhcp client stays running, but if the renewal fails,
// we will lose our IP address and connectivity without
// noticing.
if (!NetworkUtils.runDhcp(mIface, dhcpResults)) {
Log.e(TAG, "DHCP request error:" + NetworkUtils.getDhcpError());
// set our score lower than any network could go
// so we get dropped.
mFactory.setScoreFilter(-1);
// If DHCP timed out (as opposed to failing), the DHCP client will still be
// running, because in M we changed its timeout to infinite. Stop it now.
NetworkUtils.stopDhcp(mIface);
return;
}
linkProperties = dhcpResults.toLinkProperties(mIface);
}
if (config.getProxySettings() == ProxySettings.STATIC ||
config.getProxySettings() == ProxySettings.PAC) {
linkProperties.setHttpProxy(config.getHttpProxy());
}
String tcpBufferSizes = mContext.getResources().getString(
com.android.internal.R.string.config_ethernet_tcp_buffers);
if (TextUtils.isEmpty(tcpBufferSizes) == false) {
linkProperties.setTcpBufferSizes(tcpBufferSizes);
}
synchronized(EthernetNetworkFactory.this) {
if (mNetworkAgent != null) {
Log.e(TAG, "Already have a NetworkAgent - aborting new request");
return;
}
mLinkProperties = linkProperties;
mNetworkInfo.setIsAvailable(true);
mNetworkInfo.setDetailedState(DetailedState.CONNECTED, null, mHwAddr);
// Create our NetworkAgent.
mNetworkAgent = new NetworkAgent(mFactory.getLooper(), mContext,
NETWORK_TYPE, mNetworkInfo, mNetworkCapabilities, mLinkProperties,
NETWORK_SCORE) {
public void unwanted() {
synchronized(EthernetNetworkFactory.this) {
if (this == mNetworkAgent) {
NetworkUtils.stopDhcp(mIface);
mLinkProperties.clear();
mNetworkInfo.setDetailedState(DetailedState.DISCONNECTED, null,
mHwAddr);
updateAgent();
mNetworkAgent = null;
try {
mNMService.clearInterfaceAddresses(mIface);
} catch (Exception e) {
Log.e(TAG, "Failed to clear addresses or disable ipv6" + e);
}
} else {
Log.d(TAG, "Ignoring unwanted as we have a more modern " +
"instance");
}
}
};
};
}
}
});
dhcpThread.start();
}
/**
* Begin monitoring connectivity
*/
public synchronized void start(Context context, Handler target) {
// The services we use.
IBinder b = ServiceManager.getService(Context.NETWORKMANAGEMENT_SERVICE);
mNMService = INetworkManagementService.Stub.asInterface(b);
mEthernetManager = (EthernetManager) context.getSystemService(Context.ETHERNET_SERVICE);
// Interface match regex.
mIfaceMatch = context.getResources().getString(
com.android.internal.R.string.config_ethernet_iface_regex);
// Create and register our NetworkFactory.
mFactory = new LocalNetworkFactory(NETWORK_TYPE, context, target.getLooper());
mFactory.setCapabilityFilter(mNetworkCapabilities);
mFactory.setScoreFilter(-1); // this set high when we have an iface
mFactory.register();
mContext = context;
// Start tracking interface change events.
mInterfaceObserver = new InterfaceObserver();
try {
mNMService.registerObserver(mInterfaceObserver);
} catch (RemoteException e) {
Log.e(TAG, "Could not register InterfaceObserver " + e);
}
// If an Ethernet interface is already connected, start tracking that.
// Otherwise, the first Ethernet interface to appear will be tracked.
try {
final String[] ifaces = mNMService.listInterfaces();
for (String iface : ifaces) {
synchronized(this) {
if (maybeTrackInterface(iface)) {
// We have our interface. Track it.
// Note: if the interface already has link (e.g., if we
// crashed and got restarted while it was running),
// we need to fake a link up notification so we start
// configuring it. Since we're already holding the lock,
// any real link up/down notification will only arrive
// after we've done this.
if (mNMService.getInterfaceConfig(iface).hasFlag("running")) {
updateInterfaceState(iface, true);
}
break;
}
}
}
} catch (RemoteException e) {
Log.e(TAG, "Could not get list of interfaces " + e);
}
}
public synchronized void stop() {
NetworkUtils.stopDhcp(mIface);
// ConnectivityService will only forget our NetworkAgent if we send it a NetworkInfo object
// with a state of DISCONNECTED or SUSPENDED. So we can't simply clear our NetworkInfo here:
// that sets the state to IDLE, and ConnectivityService will still think we're connected.
//
// TODO: stop using explicit comparisons to DISCONNECTED / SUSPENDED in ConnectivityService,
// and instead use isConnectedOrConnecting().
mNetworkInfo.setDetailedState(DetailedState.DISCONNECTED, null, mHwAddr);
mLinkUp = false;
updateAgent();
mLinkProperties = new LinkProperties();
mNetworkAgent = null;
setInterfaceInfoLocked("", null);
mNetworkInfo = new NetworkInfo(ConnectivityManager.TYPE_ETHERNET, 0, NETWORK_TYPE, "");
mFactory.unregister();
}
private void initNetworkCapabilities() {
mNetworkCapabilities = new NetworkCapabilities();
mNetworkCapabilities.addTransportType(NetworkCapabilities.TRANSPORT_ETHERNET);
mNetworkCapabilities.addCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET);
mNetworkCapabilities.addCapability(NetworkCapabilities.NET_CAPABILITY_NOT_RESTRICTED);
// We have no useful data on bandwidth. Say 100M up and 100M down. :-(
mNetworkCapabilities.setLinkUpstreamBandwidthKbps(100 * 1000);
mNetworkCapabilities.setLinkDownstreamBandwidthKbps(100 * 1000);
}
public synchronized boolean isTrackingInterface() {
return !TextUtils.isEmpty(mIface);
}
/**
* Set interface information and notify listeners if availability is changed.
* This should be called with the lock held.
*/
private void setInterfaceInfoLocked(String iface, String hwAddr) {
boolean oldAvailable = isTrackingInterface();
mIface = iface;
mHwAddr = hwAddr;
boolean available = isTrackingInterface();
if (oldAvailable != available) {
int n = mListeners.beginBroadcast();
for (int i = 0; i < n; i++) {
try {
mListeners.getBroadcastItem(i).onAvailabilityChanged(available);
} catch (RemoteException e) {
// Do nothing here.
}
}
mListeners.finishBroadcast();
}
}
synchronized void dump(FileDescriptor fd, IndentingPrintWriter pw, String[] args) {
if (isTrackingInterface()) {
pw.println("Tracking interface: " + mIface);
pw.increaseIndent();
pw.println("MAC address: " + mHwAddr);
pw.println("Link state: " + (mLinkUp ? "up" : "down"));
pw.decreaseIndent();
} else {
pw.println("Not tracking any interface");
}
pw.println();
pw.println("NetworkInfo: " + mNetworkInfo);
pw.println("LinkProperties: " + mLinkProperties);
pw.println("NetworkAgent: " + mNetworkAgent);
}
}