1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
|
package com.wireguard.android.backend;
import android.content.Context;
import android.util.Log;
import com.wireguard.android.model.Tunnel;
import com.wireguard.android.model.Tunnel.State;
import com.wireguard.android.model.Tunnel.Statistics;
import com.wireguard.android.util.RootShell;
import com.wireguard.android.util.ToolsInstaller;
import com.wireguard.config.Config;
import java.io.File;
import java.io.FileOutputStream;
import java.nio.charset.StandardCharsets;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Set;
import java9.util.stream.Collectors;
import java9.util.stream.Stream;
/**
* WireGuard backend that uses {@code wg-quick} to implement tunnel configuration.
*/
public final class WgQuickBackend implements Backend {
private static final String TAG = "WireGuard/" + WgQuickBackend.class.getSimpleName();
private final File localTemporaryDir;
private final RootShell rootShell;
private final ToolsInstaller toolsInstaller;
public WgQuickBackend(final Context context, final RootShell rootShell,
final ToolsInstaller toolsInstaller) {
localTemporaryDir = new File(context.getCacheDir(), "tmp");
this.rootShell = rootShell;
this.toolsInstaller = toolsInstaller;
}
@Override
public Config applyConfig(final Tunnel tunnel, final Config config) throws Exception {
if (tunnel.getState() == State.UP) {
// Restart the tunnel to apply the new config.
setStateInternal(tunnel, tunnel.getConfig(), State.DOWN);
try {
setStateInternal(tunnel, config, State.UP);
} catch (final Exception e) {
// The new configuration didn't work, so try to go back to the old one.
setStateInternal(tunnel, tunnel.getConfig(), State.UP);
throw e;
}
}
return config;
}
@Override
public Set<String> enumerate() {
final List<String> output = new ArrayList<>();
// Don't throw an exception here or nothing will show up in the UI.
try {
toolsInstaller.ensureToolsAvailable();
if (rootShell.run(output, "wg show interfaces") != 0 || output.isEmpty())
return Collections.emptySet();
} catch (final Exception e) {
Log.w(TAG, "Unable to enumerate running tunnels", e);
return Collections.emptySet();
}
// wg puts all interface names on the same line. Split them into separate elements.
return Stream.of(output.get(0).split(" ")).collect(Collectors.toUnmodifiableSet());
}
@Override
public State getState(final Tunnel tunnel) {
return enumerate().contains(tunnel.getName()) ? State.UP : State.DOWN;
}
@Override
public Statistics getStatistics(final Tunnel tunnel) {
return new Statistics();
}
@Override
public State setState(final Tunnel tunnel, State state) throws Exception {
final State originalState = getState(tunnel);
if (state == State.TOGGLE)
state = originalState == State.UP ? State.DOWN : State.UP;
if (state == originalState)
return originalState;
if (state == State.UP && !new File("/sys/module/wireguard").exists())
throw new ModuleNotLoadedException("WireGuard module not loaded");
Log.d(TAG, "Changing tunnel " + tunnel.getName() + " to state " + state);
toolsInstaller.ensureToolsAvailable();
setStateInternal(tunnel, tunnel.getConfig(), state);
return getState(tunnel);
}
private void setStateInternal(final Tunnel tunnel, final Config config, final State state)
throws Exception {
final File tempFile = new File(localTemporaryDir, tunnel.getName() + ".conf");
final int result;
if (state == State.UP) {
try (FileOutputStream stream = new FileOutputStream(tempFile, false)) {
stream.write(config.toString().getBytes(StandardCharsets.UTF_8));
}
result = rootShell.run(null, "wg-quick up '" + tempFile.getAbsolutePath() + '\'');
} else {
result = rootShell.run(null, "wg-quick down '" + tempFile.getAbsolutePath() + '\'');
if (result == 0 && !tempFile.delete())
Log.w(TAG, "Couldn't delete temp config after bringing down " + tunnel.getName());
}
if (result != 0)
throw new Exception("Unable to configure tunnel (wg-quick returned " + result + ')');
}
public static class ModuleNotLoadedException extends Exception {
public ModuleNotLoadedException(final String message, final Throwable cause) {
super(message, cause);
}
public ModuleNotLoadedException(final String message) {
super(message);
}
}
}
|
