Factor shared Bluetooth code into superclass.

This commit is contained in:
akwizgran
2018-01-10 13:03:07 +00:00
parent 2f049fbead
commit 0c5976b287
11 changed files with 471 additions and 615 deletions

View File

@@ -0,0 +1,368 @@
package org.briarproject.bramble.plugin.bluetooth;
import org.briarproject.bramble.api.FormatException;
import org.briarproject.bramble.api.contact.ContactId;
import org.briarproject.bramble.api.data.BdfList;
import org.briarproject.bramble.api.keyagreement.KeyAgreementConnection;
import org.briarproject.bramble.api.keyagreement.KeyAgreementListener;
import org.briarproject.bramble.api.nullsafety.MethodsNotNullByDefault;
import org.briarproject.bramble.api.nullsafety.ParametersNotNullByDefault;
import org.briarproject.bramble.api.plugin.Backoff;
import org.briarproject.bramble.api.plugin.PluginException;
import org.briarproject.bramble.api.plugin.TransportId;
import org.briarproject.bramble.api.plugin.duplex.DuplexPlugin;
import org.briarproject.bramble.api.plugin.duplex.DuplexPluginCallback;
import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
import org.briarproject.bramble.api.properties.TransportProperties;
import org.briarproject.bramble.util.StringUtils;
import java.io.IOException;
import java.security.SecureRandom;
import java.util.Collection;
import java.util.Map;
import java.util.Map.Entry;
import java.util.UUID;
import java.util.concurrent.Callable;
import java.util.concurrent.Executor;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.logging.Logger;
import javax.annotation.Nullable;
import static java.util.logging.Level.INFO;
import static java.util.logging.Level.WARNING;
import static org.briarproject.bramble.api.keyagreement.KeyAgreementConstants.TRANSPORT_ID_BLUETOOTH;
import static org.briarproject.bramble.api.plugin.BluetoothConstants.ID;
import static org.briarproject.bramble.api.plugin.BluetoothConstants.PREF_BT_ENABLE;
import static org.briarproject.bramble.api.plugin.BluetoothConstants.PROP_ADDRESS;
import static org.briarproject.bramble.api.plugin.BluetoothConstants.PROP_UUID;
import static org.briarproject.bramble.api.plugin.BluetoothConstants.UUID_BYTES;
import static org.briarproject.bramble.util.PrivacyUtils.scrubMacAddress;
@MethodsNotNullByDefault
@ParametersNotNullByDefault
abstract class BluetoothPlugin<SS> implements DuplexPlugin {
private static final Logger LOG =
Logger.getLogger(BluetoothPlugin.class.getName());
final Executor ioExecutor;
private final SecureRandom secureRandom;
private final Backoff backoff;
private final DuplexPluginCallback callback;
private final int maxLatency;
private final AtomicBoolean used = new AtomicBoolean(false);
private volatile boolean running = false;
private volatile SS socket = null;
abstract void initialiseAdapter() throws IOException;
abstract boolean isAdapterEnabled();
abstract void enableAdapter();
@Nullable
abstract String getBluetoothAddress();
abstract SS openServerSocket(String uuid) throws IOException;
abstract void tryToClose(@Nullable SS ss);
abstract DuplexTransportConnection acceptConnection(SS ss)
throws IOException;
abstract boolean isValidAddress(String address);
abstract DuplexTransportConnection connectTo(String address, String uuid)
throws IOException;
BluetoothPlugin(Executor ioExecutor, SecureRandom secureRandom,
Backoff backoff, DuplexPluginCallback callback, int maxLatency) {
this.ioExecutor = ioExecutor;
this.secureRandom = secureRandom;
this.backoff = backoff;
this.callback = callback;
this.maxLatency = maxLatency;
}
void onAdapterEnabled() {
LOG.info("Bluetooth enabled");
bind();
}
void onAdapterDisabled() {
LOG.info("Bluetooth disabled");
tryToClose(socket);
callback.transportDisabled();
}
@Override
public TransportId getId() {
return ID;
}
@Override
public int getMaxLatency() {
return maxLatency;
}
@Override
public int getMaxIdleTime() {
// Bluetooth detects dead connections so we don't need keepalives
return Integer.MAX_VALUE;
}
@Override
public void start() throws PluginException {
if (used.getAndSet(true)) throw new IllegalStateException();
try {
initialiseAdapter();
} catch (IOException e) {
throw new PluginException(e);
}
running = true;
// If Bluetooth is enabled, bind a socket
if (isAdapterEnabled()) {
bind();
} else {
// Enable Bluetooth if settings allow
if (callback.getSettings().getBoolean(PREF_BT_ENABLE, false)) {
enableAdapter();
} else {
LOG.info("Not enabling Bluetooth");
}
}
}
private void bind() {
ioExecutor.execute(() -> {
if (!isRunning()) return;
String address = getBluetoothAddress();
if (LOG.isLoggable(INFO))
LOG.info("Local address " + scrubMacAddress(address));
if (!StringUtils.isNullOrEmpty(address)) {
// Advertise our Bluetooth address to contacts
TransportProperties p = new TransportProperties();
p.put(PROP_ADDRESS, address);
callback.mergeLocalProperties(p);
}
// Bind a server socket to accept connections from contacts
SS ss;
try {
ss = openServerSocket(getUuid());
} catch (IOException e) {
if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
return;
}
if (!isRunning()) {
tryToClose(ss);
return;
}
socket = ss;
backoff.reset();
callback.transportEnabled();
acceptContactConnections();
});
}
private String getUuid() {
String uuid = callback.getLocalProperties().get(PROP_UUID);
if (uuid == null) {
byte[] random = new byte[UUID_BYTES];
secureRandom.nextBytes(random);
uuid = UUID.nameUUIDFromBytes(random).toString();
TransportProperties p = new TransportProperties();
p.put(PROP_UUID, uuid);
callback.mergeLocalProperties(p);
}
return uuid;
}
private void acceptContactConnections() {
while (true) {
DuplexTransportConnection conn;
try {
conn = acceptConnection(socket);
} catch (IOException e) {
// This is expected when the socket is closed
if (LOG.isLoggable(INFO)) LOG.info(e.toString());
return;
}
backoff.reset();
callback.incomingConnectionCreated(conn);
if (!running) return;
}
}
@Override
public void stop() {
running = false;
tryToClose(socket);
callback.transportDisabled();
}
@Override
public boolean isRunning() {
return running;
}
@Override
public boolean shouldPoll() {
return true;
}
@Override
public int getPollingInterval() {
return backoff.getPollingInterval();
}
@Override
public void poll(Collection<ContactId> connected) {
if (!isRunning()) return;
backoff.increment();
// Try to connect to known devices in parallel
Map<ContactId, TransportProperties> remote =
callback.getRemoteProperties();
for (Entry<ContactId, TransportProperties> e : remote.entrySet()) {
ContactId c = e.getKey();
if (connected.contains(c)) continue;
String address = e.getValue().get(PROP_ADDRESS);
if (StringUtils.isNullOrEmpty(address)) continue;
String uuid = e.getValue().get(PROP_UUID);
if (StringUtils.isNullOrEmpty(uuid)) continue;
ioExecutor.execute(() -> {
if (!isRunning()) return;
DuplexTransportConnection conn = connect(address, uuid);
if (conn != null) {
backoff.reset();
callback.outgoingConnectionCreated(c, conn);
}
});
}
}
@Nullable
private DuplexTransportConnection connect(String address, String uuid) {
// Validate the address
if (!isValidAddress(address)) {
if (LOG.isLoggable(WARNING))
// Not scrubbing here to be able to figure out the problem
LOG.warning("Invalid address " + address);
return null;
}
// Validate the UUID
try {
//noinspection ResultOfMethodCallIgnored
UUID.fromString(uuid);
} catch (IllegalArgumentException e) {
if (LOG.isLoggable(WARNING)) LOG.warning("Invalid UUID " + uuid);
return null;
}
if (LOG.isLoggable(INFO))
LOG.info("Connecting to " + scrubMacAddress(address));
try {
DuplexTransportConnection conn = connectTo(address, uuid);
if (LOG.isLoggable(INFO))
LOG.info("Connected to " + scrubMacAddress(address));
return conn;
} catch (IOException e) {
if (LOG.isLoggable(INFO))
LOG.info("Could not connect to " + scrubMacAddress(address));
return null;
}
}
@Override
public DuplexTransportConnection createConnection(ContactId c) {
if (!isRunning()) return null;
TransportProperties p = callback.getRemoteProperties(c);
String address = p.get(PROP_ADDRESS);
if (StringUtils.isNullOrEmpty(address)) return null;
String uuid = p.get(PROP_UUID);
if (StringUtils.isNullOrEmpty(uuid)) return null;
return connect(address, uuid);
}
@Override
public boolean supportsKeyAgreement() {
return true;
}
@Override
public KeyAgreementListener createKeyAgreementListener(byte[] commitment) {
if (!isRunning()) return null;
// There's no point listening if we can't discover our own address
String address = getBluetoothAddress();
if (address == null) return null;
// No truncation necessary because COMMIT_LENGTH = 16
String uuid = UUID.nameUUIDFromBytes(commitment).toString();
if (LOG.isLoggable(INFO)) LOG.info("Key agreement UUID " + uuid);
// Bind a server socket for receiving key agreement connections
SS ss;
try {
ss = openServerSocket(uuid);
} catch (IOException e) {
if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
return null;
}
if (!isRunning()) {
tryToClose(ss);
return null;
}
BdfList descriptor = new BdfList();
descriptor.add(TRANSPORT_ID_BLUETOOTH);
descriptor.add(StringUtils.macToBytes(address));
return new BluetoothKeyAgreementListener(descriptor, ss);
}
@Override
public DuplexTransportConnection createKeyAgreementConnection(
byte[] commitment, BdfList descriptor, long timeout) {
if (!isRunning()) return null;
String address;
try {
address = parseAddress(descriptor);
} catch (FormatException e) {
LOG.info("Invalid address in key agreement descriptor");
return null;
}
// No truncation necessary because COMMIT_LENGTH = 16
String uuid = UUID.nameUUIDFromBytes(commitment).toString();
if (LOG.isLoggable(INFO))
LOG.info("Connecting to key agreement UUID " + uuid);
return connect(address, uuid);
}
private String parseAddress(BdfList descriptor) throws FormatException {
byte[] mac = descriptor.getRaw(1);
if (mac.length != 6) throw new FormatException();
return StringUtils.macToString(mac);
}
private class BluetoothKeyAgreementListener extends KeyAgreementListener {
private final SS ss;
private BluetoothKeyAgreementListener(BdfList descriptor, SS ss) {
super(descriptor);
this.ss = ss;
}
@Override
public Callable<KeyAgreementConnection> listen() {
return () -> {
DuplexTransportConnection conn = acceptConnection(ss);
if (LOG.isLoggable(INFO))
LOG.info(ID.getString() + ": Incoming connection");
return new KeyAgreementConnection(conn, ID);
};
}
@Override
public void close() {
tryToClose(ss);
}
}
}