wireguard-android/tunnel/src/main/java/com/wireguard/android/backend/GoBackend.java

293 lines
10 KiB
Java

/*
* Copyright © 2017-2019 WireGuard LLC. All Rights Reserved.
* SPDX-License-Identifier: Apache-2.0
*/
package com.wireguard.android.backend;
import android.content.Context;
import android.content.Intent;
import android.os.Build;
import android.os.ParcelFileDescriptor;
import androidx.annotation.Nullable;
import androidx.collection.ArraySet;
import android.util.Log;
import com.wireguard.android.backend.BackendException.Reason;
import com.wireguard.android.backend.Tunnel.State;
import com.wireguard.android.util.SharedLibraryLoader;
import com.wireguard.config.Config;
import com.wireguard.config.InetNetwork;
import com.wireguard.config.Peer;
import com.wireguard.crypto.Key;
import com.wireguard.crypto.KeyFormatException;
import java.net.InetAddress;
import java.util.Collections;
import java.util.Set;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
import java9.util.concurrent.CompletableFuture;
public final class GoBackend implements Backend {
private static final String TAG = "WireGuard/" + GoBackend.class.getSimpleName();
private static CompletableFuture<VpnService> vpnService = new CompletableFuture<>();
public interface AlwaysOnCallback {
void alwaysOnTriggered();
}
@Nullable private static AlwaysOnCallback alwaysOnCallback;
public static void setAlwaysOnCallback(AlwaysOnCallback cb) {
alwaysOnCallback = cb;
}
private final Context context;
@Nullable private Tunnel currentTunnel;
@Nullable private Config currentConfig;
private int currentTunnelHandle = -1;
public GoBackend(final Context context) {
SharedLibraryLoader.loadSharedLibrary(context, "wg-go");
this.context = context;
}
private static native String wgGetConfig(int handle);
private static native int wgGetSocketV4(int handle);
private static native int wgGetSocketV6(int handle);
private static native void wgTurnOff(int handle);
private static native int wgTurnOn(String ifName, int tunFd, String settings);
private static native String wgVersion();
@Override
public Set<String> getRunningTunnelNames() {
if (currentTunnel != null) {
final Set<String> runningTunnels = new ArraySet<>();
runningTunnels.add(currentTunnel.getName());
return runningTunnels;
}
return Collections.emptySet();
}
@Override
public State getState(final Tunnel tunnel) {
return currentTunnel == tunnel ? State.UP : State.DOWN;
}
@Override
public Statistics getStatistics(final Tunnel tunnel) {
final Statistics stats = new Statistics();
if (tunnel != currentTunnel) {
return stats;
}
final String config = wgGetConfig(currentTunnelHandle);
Key key = null;
long rx = 0, tx = 0;
for (final String line : config.split("\\n")) {
if (line.startsWith("public_key=")) {
if (key != null)
stats.add(key, rx, tx);
rx = 0;
tx = 0;
try {
key = Key.fromHex(line.substring(11));
} catch (final KeyFormatException ignored) {
key = null;
}
} else if (line.startsWith("rx_bytes=")) {
if (key == null)
continue;
try {
rx = Long.parseLong(line.substring(9));
} catch (final NumberFormatException ignored) {
rx = 0;
}
} else if (line.startsWith("tx_bytes=")) {
if (key == null)
continue;
try {
tx = Long.parseLong(line.substring(9));
} catch (final NumberFormatException ignored) {
tx = 0;
}
}
}
if (key != null)
stats.add(key, rx, tx);
return stats;
}
@Override
public String getVersion() {
return wgVersion();
}
@Override
public State setState(final Tunnel tunnel, State state, @Nullable final Config config) throws Exception {
final State originalState = getState(tunnel);
if (state == State.TOGGLE)
state = originalState == State.UP ? State.DOWN : State.UP;
if (state == originalState && tunnel == currentTunnel && config == currentConfig)
return originalState;
if (state == State.UP) {
final Config originalConfig = currentConfig;
final Tunnel originalTunnel = currentTunnel;
if (currentTunnel != null)
setStateInternal(currentTunnel, null, State.DOWN);
try {
setStateInternal(tunnel, config, state);
} catch(final Exception e) {
if (originalTunnel != null)
setStateInternal(originalTunnel, originalConfig, State.UP);
throw e;
}
} else if (state == State.DOWN && tunnel == currentTunnel) {
setStateInternal(tunnel, null, State.DOWN);
}
return getState(tunnel);
}
private void setStateInternal(final Tunnel tunnel, @Nullable final Config config, final State state)
throws Exception {
Log.i(TAG, "Bringing tunnel " + tunnel.getName() + " " + state);
if (state == State.UP) {
if (config == null)
throw new BackendException(Reason.TUNNEL_MISSING_CONFIG);
if (VpnService.prepare(context) != null)
throw new BackendException(Reason.VPN_NOT_AUTHORIZED);
final VpnService service;
if (!vpnService.isDone())
startVpnService();
try {
service = vpnService.get(2, TimeUnit.SECONDS);
} catch (final TimeoutException e) {
final Exception be = new BackendException(Reason.UNABLE_TO_START_VPN);
be.initCause(e);
throw be;
}
service.setOwner(this);
if (currentTunnelHandle != -1) {
Log.w(TAG, "Tunnel already up");
return;
}
// Build config
final String goConfig = config.toWgUserspaceString();
// Create the vpn tunnel with android API
final VpnService.Builder builder = service.getBuilder();
builder.setSession(tunnel.getName());
for (final String excludedApplication : config.getInterface().getExcludedApplications())
builder.addDisallowedApplication(excludedApplication);
for (final InetNetwork addr : config.getInterface().getAddresses())
builder.addAddress(addr.getAddress(), addr.getMask());
for (final InetAddress addr : config.getInterface().getDnsServers())
builder.addDnsServer(addr.getHostAddress());
for (final Peer peer : config.getPeers()) {
for (final InetNetwork addr : peer.getAllowedIps())
builder.addRoute(addr.getAddress(), addr.getMask());
}
builder.setMtu(config.getInterface().getMtu().orElse(1280));
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q)
builder.setMetered(false);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M)
service.setUnderlyingNetworks(null);
builder.setBlocking(true);
try (final ParcelFileDescriptor tun = builder.establish()) {
if (tun == null)
throw new BackendException(Reason.TUN_CREATION_ERROR);
Log.d(TAG, "Go backend v" + wgVersion());
currentTunnelHandle = wgTurnOn(tunnel.getName(), tun.detachFd(), goConfig);
}
if (currentTunnelHandle < 0)
throw new BackendException(Reason.GO_ACTIVATION_ERROR_CODE, currentTunnelHandle);
currentTunnel = tunnel;
currentConfig = config;
service.protect(wgGetSocketV4(currentTunnelHandle));
service.protect(wgGetSocketV6(currentTunnelHandle));
} else {
if (currentTunnelHandle == -1) {
Log.w(TAG, "Tunnel already down");
return;
}
wgTurnOff(currentTunnelHandle);
currentTunnel = null;
currentTunnelHandle = -1;
currentConfig = null;
}
tunnel.onStateChange(state);
}
private void startVpnService() {
Log.d(TAG, "Requesting to start VpnService");
context.startService(new Intent(context, VpnService.class));
}
public static class VpnService extends android.net.VpnService {
@Nullable private GoBackend owner;
public void setOwner(final GoBackend owner) {
this.owner = owner;
}
public Builder getBuilder() {
return new Builder();
}
@Override
public void onCreate() {
vpnService.complete(this);
super.onCreate();
}
@Override
public void onDestroy() {
if (owner != null) {
final Tunnel tunnel = owner.currentTunnel;
if (tunnel != null) {
if (owner.currentTunnelHandle != -1)
wgTurnOff(owner.currentTunnelHandle);
owner.currentTunnel = null;
owner.currentTunnelHandle = -1;
owner.currentConfig = null;
tunnel.onStateChange(State.DOWN);
}
}
vpnService = vpnService.newIncompleteFuture();
super.onDestroy();
}
@Override
public int onStartCommand(@Nullable final Intent intent, final int flags, final int startId) {
vpnService.complete(this);
if (intent == null || intent.getComponent() == null || !intent.getComponent().getPackageName().equals(getPackageName())) {
Log.d(TAG, "Service started by Always-on VPN feature");
if (alwaysOnCallback != null)
alwaysOnCallback.alwaysOnTriggered();
}
return super.onStartCommand(intent, flags, startId);
}
}
}