| // Copyright (C) 2008 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.google.gerrit.sshd; |
| |
| import static com.google.gerrit.server.ssh.SshAddressesModule.IANA_SSH_PORT; |
| import static java.util.concurrent.TimeUnit.MILLISECONDS; |
| import static java.util.concurrent.TimeUnit.SECONDS; |
| import static org.apache.sshd.core.CoreModuleProperties.AUTH_TIMEOUT; |
| import static org.apache.sshd.core.CoreModuleProperties.IDLE_TIMEOUT; |
| import static org.apache.sshd.core.CoreModuleProperties.MAX_AUTH_REQUESTS; |
| import static org.apache.sshd.core.CoreModuleProperties.MAX_CONCURRENT_SESSIONS; |
| import static org.apache.sshd.core.CoreModuleProperties.NIO2_READ_TIMEOUT; |
| import static org.apache.sshd.core.CoreModuleProperties.REKEY_BYTES_LIMIT; |
| import static org.apache.sshd.core.CoreModuleProperties.REKEY_TIME_LIMIT; |
| import static org.apache.sshd.core.CoreModuleProperties.SERVER_IDENTIFICATION; |
| import static org.apache.sshd.core.CoreModuleProperties.WAIT_FOR_SPACE_TIMEOUT; |
| |
| import com.google.common.base.Strings; |
| import com.google.common.collect.Iterables; |
| import com.google.common.flogger.FluentLogger; |
| import com.google.gerrit.common.Version; |
| import com.google.gerrit.extensions.events.LifecycleListener; |
| import com.google.gerrit.metrics.Counter0; |
| import com.google.gerrit.metrics.Description; |
| import com.google.gerrit.metrics.MetricMaker; |
| import com.google.gerrit.server.config.ConfigUtil; |
| import com.google.gerrit.server.config.GerritServerConfig; |
| import com.google.gerrit.server.ssh.HostKey; |
| import com.google.gerrit.server.ssh.SshAdvertisedAddresses; |
| import com.google.gerrit.server.ssh.SshInfo; |
| import com.google.gerrit.server.ssh.SshListenAddresses; |
| import com.google.gerrit.server.util.IdGenerator; |
| import com.google.gerrit.server.util.SocketUtil; |
| import com.google.inject.Inject; |
| import com.google.inject.Singleton; |
| import java.io.File; |
| import java.io.IOException; |
| import java.net.InetAddress; |
| import java.net.InetSocketAddress; |
| import java.net.SocketAddress; |
| import java.net.UnknownHostException; |
| import java.security.GeneralSecurityException; |
| import java.security.InvalidKeyException; |
| import java.security.KeyPair; |
| import java.security.PublicKey; |
| import java.time.Duration; |
| import java.util.ArrayList; |
| import java.util.Arrays; |
| import java.util.Collection; |
| import java.util.Collections; |
| import java.util.Iterator; |
| import java.util.List; |
| import java.util.concurrent.CountDownLatch; |
| import java.util.concurrent.ExecutorService; |
| import java.util.concurrent.TimeUnit; |
| import java.util.concurrent.atomic.AtomicInteger; |
| import org.apache.mina.transport.socket.SocketSessionConfig; |
| import org.apache.sshd.common.BaseBuilder; |
| import org.apache.sshd.common.NamedFactory; |
| import org.apache.sshd.common.NamedResource; |
| import org.apache.sshd.common.cipher.Cipher; |
| import org.apache.sshd.common.compression.BuiltinCompressions; |
| import org.apache.sshd.common.compression.Compression; |
| import org.apache.sshd.common.file.nonefs.NoneFileSystemFactory; |
| import org.apache.sshd.common.forward.DefaultForwarderFactory; |
| import org.apache.sshd.common.future.CloseFuture; |
| import org.apache.sshd.common.future.SshFutureListener; |
| import org.apache.sshd.common.io.AbstractIoServiceFactory; |
| import org.apache.sshd.common.io.IoAcceptor; |
| import org.apache.sshd.common.io.IoServiceFactory; |
| import org.apache.sshd.common.io.IoServiceFactoryFactory; |
| import org.apache.sshd.common.io.IoSession; |
| import org.apache.sshd.common.io.nio2.Nio2ServiceFactoryFactory; |
| import org.apache.sshd.common.kex.KeyExchangeFactory; |
| import org.apache.sshd.common.keyprovider.KeyPairProvider; |
| import org.apache.sshd.common.mac.Mac; |
| import org.apache.sshd.common.random.Random; |
| import org.apache.sshd.common.random.SingletonRandomFactory; |
| import org.apache.sshd.common.session.Session; |
| import org.apache.sshd.common.session.helpers.AbstractSession; |
| import org.apache.sshd.common.session.helpers.DefaultUnknownChannelReferenceHandler; |
| import org.apache.sshd.common.util.buffer.Buffer; |
| import org.apache.sshd.common.util.buffer.ByteArrayBuffer; |
| import org.apache.sshd.common.util.net.SshdSocketAddress; |
| import org.apache.sshd.common.util.security.SecurityUtils; |
| import org.apache.sshd.mina.MinaServiceFactoryFactory; |
| import org.apache.sshd.mina.MinaSession; |
| import org.apache.sshd.server.ServerBuilder; |
| import org.apache.sshd.server.SshServer; |
| import org.apache.sshd.server.auth.UserAuthFactory; |
| import org.apache.sshd.server.auth.gss.GSSAuthenticator; |
| import org.apache.sshd.server.auth.gss.UserAuthGSSFactory; |
| import org.apache.sshd.server.auth.pubkey.PublickeyAuthenticator; |
| import org.apache.sshd.server.auth.pubkey.UserAuthPublicKeyFactory; |
| import org.apache.sshd.server.command.CommandFactory; |
| import org.apache.sshd.server.forward.ForwardingFilter; |
| import org.apache.sshd.server.global.CancelTcpipForwardHandler; |
| import org.apache.sshd.server.global.KeepAliveHandler; |
| import org.apache.sshd.server.global.NoMoreSessionsHandler; |
| import org.apache.sshd.server.global.TcpipForwardHandler; |
| import org.apache.sshd.server.session.ServerSessionImpl; |
| import org.apache.sshd.server.session.SessionFactory; |
| import org.bouncycastle.crypto.prng.RandomGenerator; |
| import org.bouncycastle.crypto.prng.VMPCRandomGenerator; |
| import org.eclipse.jgit.lib.Config; |
| |
| /** |
| * SSH daemon to communicate with Gerrit. |
| * |
| * <p>Use a Git URL such as <code>ssh://${email}@${host}:${port}/${path}</code>, e.g. {@code |
| * ssh://sop@google.com@gerrit.com:8010/tools/gerrit.git} to access the SSH daemon itself. |
| * |
| * <p>Versions of Git before 1.5.3 may require setting the username and port properties in the |
| * user's {@code ~/.ssh/config} file, and using a host alias through a URL such as {@code |
| * gerrit-alias:/tools/gerrit.git}: |
| * |
| * <pre>{@code |
| * Host gerrit-alias |
| * User sop@google.com |
| * Hostname gerrit.com |
| * Port 8010 |
| * }</pre> |
| */ |
| @Singleton |
| public class SshDaemon extends SshServer implements SshInfo, LifecycleListener { |
| private static final FluentLogger logger = FluentLogger.forEnclosingClass(); |
| |
| public enum SshSessionBackend { |
| MINA, |
| NIO2 |
| } |
| |
| private final List<SocketAddress> listen; |
| private final List<String> advertised; |
| private final boolean keepAlive; |
| private final List<HostKey> hostKeys; |
| private volatile IoAcceptor daemonAcceptor; |
| private final Config cfg; |
| private final long gracefulStopTimeout; |
| |
| @Inject |
| SshDaemon( |
| CommandFactory commandFactory, |
| NoShell noShell, |
| PublickeyAuthenticator userAuth, |
| GerritGSSAuthenticator kerberosAuth, |
| KeyPairProvider hostKeyProvider, |
| IdGenerator idGenerator, |
| @GerritServerConfig Config cfg, |
| SshLog sshLog, |
| @SshListenAddresses List<SocketAddress> listen, |
| @SshAdvertisedAddresses List<String> advertised, |
| MetricMaker metricMaker) { |
| setPort(IANA_SSH_PORT /* never used */); |
| |
| this.cfg = cfg; |
| this.listen = listen; |
| this.advertised = advertised; |
| keepAlive = cfg.getBoolean("sshd", "tcpkeepalive", true); |
| |
| SERVER_IDENTIFICATION.set( |
| this, |
| "GerritCodeReview_" |
| + Version.getVersion() // |
| + " (" |
| + super.getVersion() |
| + ")"); |
| MAX_AUTH_REQUESTS.set(this, cfg.getInt("sshd", "maxAuthTries", 6)); |
| AUTH_TIMEOUT.set( |
| this, |
| Duration.ofSeconds( |
| MILLISECONDS.convert( |
| ConfigUtil.getTimeUnit(cfg, "sshd", null, "loginGraceTime", 120, SECONDS), |
| SECONDS))); |
| |
| long idleTimeoutSeconds = ConfigUtil.getTimeUnit(cfg, "sshd", null, "idleTimeout", 0, SECONDS); |
| IDLE_TIMEOUT.set(this, Duration.ofSeconds(SECONDS.toMillis(idleTimeoutSeconds))); |
| NIO2_READ_TIMEOUT.set(this, Duration.ofSeconds(SECONDS.toMillis(idleTimeoutSeconds))); |
| |
| long rekeyTimeLimit = |
| ConfigUtil.getTimeUnit(cfg, "sshd", null, "rekeyTimeLimit", 3600, SECONDS); |
| REKEY_TIME_LIMIT.set(this, Duration.ofSeconds(SECONDS.toMillis(rekeyTimeLimit))); |
| |
| REKEY_BYTES_LIMIT.set( |
| this, cfg.getLong("sshd", "rekeyBytesLimit", 1024 * 1024 * 1024 /* 1GB */)); |
| |
| long waitTimeoutSeconds = ConfigUtil.getTimeUnit(cfg, "sshd", null, "waitTimeout", 30, SECONDS); |
| WAIT_FOR_SPACE_TIMEOUT.set(this, Duration.ofSeconds(SECONDS.toMillis(waitTimeoutSeconds))); |
| |
| final int maxConnectionsPerUser = cfg.getInt("sshd", "maxConnectionsPerUser", 64); |
| if (0 < maxConnectionsPerUser) { |
| MAX_CONCURRENT_SESSIONS.set(this, maxConnectionsPerUser); |
| } |
| |
| final String kerberosKeytab = cfg.getString("sshd", null, "kerberosKeytab"); |
| final String kerberosPrincipal = cfg.getString("sshd", null, "kerberosPrincipal"); |
| |
| final boolean enableCompression = cfg.getBoolean("sshd", "enableCompression", false); |
| |
| SshSessionBackend backend = cfg.getEnum("sshd", null, "backend", SshSessionBackend.NIO2); |
| boolean channelIdTracking = cfg.getBoolean("sshd", "enableChannelIdTracking", true); |
| |
| gracefulStopTimeout = cfg.getTimeUnit("sshd", null, "gracefulStopTimeout", 0, TimeUnit.SECONDS); |
| |
| System.setProperty( |
| IoServiceFactoryFactory.class.getName(), |
| backend == SshSessionBackend.MINA |
| ? MinaServiceFactoryFactory.class.getName() |
| : Nio2ServiceFactoryFactory.class.getName()); |
| |
| initProviderBouncyCastle(cfg); |
| initCiphers(cfg); |
| initKeyExchanges(cfg); |
| initMacs(cfg); |
| initSignatures(); |
| initChannels(); |
| initUnknownChannelReferenceHandler(channelIdTracking); |
| initForwarding(); |
| initFileSystemFactory(); |
| initSubsystems(); |
| initCompression(enableCompression); |
| initUserAuth(userAuth, kerberosAuth, kerberosKeytab, kerberosPrincipal); |
| setKeyPairProvider(hostKeyProvider); |
| setCommandFactory(commandFactory); |
| setShellFactory(noShell); |
| |
| final AtomicInteger connected = new AtomicInteger(); |
| metricMaker.newCallbackMetric( |
| "sshd/sessions/connected", |
| Integer.class, |
| new Description("Currently connected SSH sessions").setGauge().setUnit("sessions"), |
| connected::get); |
| |
| final Counter0 sessionsCreated = |
| metricMaker.newCounter( |
| "sshd/sessions/created", |
| new Description("Rate of new SSH sessions").setRate().setUnit("sessions")); |
| |
| final Counter0 authFailures = |
| metricMaker.newCounter( |
| "sshd/sessions/authentication_failures", |
| new Description("Rate of SSH authentication failures").setRate().setUnit("failures")); |
| |
| setSessionFactory( |
| new SessionFactory(this) { |
| @Override |
| protected ServerSessionImpl createSession(IoSession io) throws Exception { |
| connected.incrementAndGet(); |
| sessionsCreated.increment(); |
| if (io instanceof MinaSession) { |
| if (((MinaSession) io).getSession().getConfig() instanceof SocketSessionConfig) { |
| ((SocketSessionConfig) ((MinaSession) io).getSession().getConfig()) |
| .setKeepAlive(keepAlive); |
| } |
| } |
| |
| ServerSessionImpl s = super.createSession(io); |
| int id = idGenerator.next(); |
| SocketAddress peer = io.getRemoteAddress(); |
| final SshSession sd = new SshSession(id, peer); |
| s.setAttribute(SshSession.KEY, sd); |
| |
| // Log a session close without authentication as a failure. |
| // |
| s.addCloseFutureListener( |
| future -> { |
| connected.decrementAndGet(); |
| if (sd.isAuthenticationError()) { |
| authFailures.increment(); |
| sshLog.onAuthFail(sd); |
| } |
| }); |
| return s; |
| } |
| |
| @Override |
| protected ServerSessionImpl doCreateSession(IoSession ioSession) throws Exception { |
| return new ServerSessionImpl(getServer(), ioSession); |
| } |
| }); |
| setGlobalRequestHandlers( |
| Arrays.asList( |
| new KeepAliveHandler(), |
| new NoMoreSessionsHandler(), |
| new TcpipForwardHandler(), |
| new CancelTcpipForwardHandler())); |
| |
| hostKeys = computeHostKeys(); |
| } |
| |
| @Override |
| public List<HostKey> getHostKeys() { |
| return hostKeys; |
| } |
| |
| public IoAcceptor getIoAcceptor() { |
| return daemonAcceptor; |
| } |
| |
| @Override |
| public synchronized void start() { |
| if (daemonAcceptor == null && !listen.isEmpty()) { |
| checkConfig(); |
| if (getSessionFactory() == null) { |
| setSessionFactory(createSessionFactory()); |
| } |
| setupSessionTimeout(getSessionFactory()); |
| daemonAcceptor = createAcceptor(); |
| |
| try { |
| String listenAddress = cfg.getString("sshd", null, "listenAddress"); |
| boolean rewrite = !Strings.isNullOrEmpty(listenAddress) && listenAddress.endsWith(":0"); |
| daemonAcceptor.bind(listen); |
| if (rewrite) { |
| SocketAddress bound = Iterables.getOnlyElement(daemonAcceptor.getBoundAddresses()); |
| cfg.setString("sshd", null, "listenAddress", format((InetSocketAddress) bound)); |
| } |
| } catch (IOException e) { |
| throw new IllegalStateException("Cannot bind to " + addressList(), e); |
| } |
| |
| logger.atInfo().log("Started Gerrit %s on %s", getVersion(), addressList()); |
| } |
| } |
| |
| private static String format(InetSocketAddress s) { |
| return String.format("%s:%d", s.getAddress().getHostAddress(), s.getPort()); |
| } |
| |
| @Override |
| public synchronized void stop() { |
| if (daemonAcceptor != null) { |
| try { |
| if (gracefulStopTimeout > 0) { |
| logger.atInfo().log( |
| "Stopping SSHD sessions gracefully with %d seconds timeout.", gracefulStopTimeout); |
| daemonAcceptor.unbind(daemonAcceptor.getBoundAddresses()); |
| waitForSessionClose(); |
| } |
| daemonAcceptor.close(true).await(); |
| shutdownExecutors(); |
| logger.atInfo().log("Stopped Gerrit SSHD"); |
| } catch (IOException e) { |
| logger.atWarning().withCause(e).log("Exception caught while closing"); |
| } finally { |
| daemonAcceptor = null; |
| } |
| } |
| } |
| |
| private void waitForSessionClose() { |
| Collection<IoSession> ioSessions = daemonAcceptor.getManagedSessions().values(); |
| CountDownLatch allSessionsClosed = new CountDownLatch(ioSessions.size()); |
| for (IoSession io : ioSessions) { |
| AbstractSession serverSession = AbstractSession.getSession(io, true); |
| SshSession sshSession = |
| serverSession != null ? serverSession.getAttribute(SshSession.KEY) : null; |
| if (sshSession != null && sshSession.requiresGracefulStop()) { |
| logger.atFine().log("Waiting for session %s to stop.", io.getId()); |
| io.addCloseFutureListener( |
| new SshFutureListener<CloseFuture>() { |
| @Override |
| public void operationComplete(CloseFuture future) { |
| logger.atFine().log("Session %s was stopped.", io.getId()); |
| allSessionsClosed.countDown(); |
| } |
| }); |
| } else { |
| logger.atFine().log("Stopping session %s immediately.", io.getId()); |
| io.close(true); |
| allSessionsClosed.countDown(); |
| } |
| } |
| try { |
| if (!allSessionsClosed.await(gracefulStopTimeout, TimeUnit.SECONDS)) { |
| logger.atWarning().log( |
| "Timeout waiting for SSH session to close. SSHD will be shut down immediately."); |
| } |
| } catch (InterruptedException e) { |
| logger.atWarning().withCause(e).log( |
| "Interrupted waiting for SSH-sessions to close. SSHD will be shut down immediately."); |
| } |
| } |
| |
| private void shutdownExecutors() { |
| if (executor != null) { |
| executor.shutdownNow(); |
| } |
| |
| IoServiceFactory serviceFactory = getIoServiceFactory(); |
| if (serviceFactory instanceof AbstractIoServiceFactory) { |
| shutdownServiceFactoryExecutor((AbstractIoServiceFactory) serviceFactory); |
| } |
| } |
| |
| private void shutdownServiceFactoryExecutor(AbstractIoServiceFactory ioServiceFactory) { |
| ioServiceFactory.close(true); |
| ExecutorService serviceFactoryExecutor = ioServiceFactory.getExecutorService(); |
| if (serviceFactoryExecutor != null && serviceFactoryExecutor != executor) { |
| serviceFactoryExecutor.shutdownNow(); |
| } |
| } |
| |
| @Override |
| protected void checkConfig() { |
| super.checkConfig(); |
| if (myHostKeys().isEmpty()) { |
| throw new IllegalStateException("No SSHD host key"); |
| } |
| } |
| |
| private List<HostKey> computeHostKeys() { |
| if (listen.isEmpty()) { |
| return Collections.emptyList(); |
| } |
| |
| List<HostKey> r = new ArrayList<>(); |
| List<PublicKey> keys = myHostKeys(); |
| for (PublicKey pub : keys) { |
| Buffer buf = new ByteArrayBuffer(); |
| buf.putRawPublicKey(pub); |
| byte[] keyBin = buf.getCompactData(); |
| |
| for (String addr : advertised) { |
| r.add(new HostKey(addr, keyBin)); |
| } |
| } |
| |
| return Collections.unmodifiableList(r); |
| } |
| |
| private List<PublicKey> myHostKeys() { |
| KeyPairProvider p = getKeyPairProvider(); |
| List<PublicKey> keys = new ArrayList<>(6); |
| try { |
| addPublicKey(keys, p, KeyPairProvider.SSH_ED25519); |
| addPublicKey(keys, p, KeyPairProvider.ECDSA_SHA2_NISTP256); |
| addPublicKey(keys, p, KeyPairProvider.ECDSA_SHA2_NISTP384); |
| addPublicKey(keys, p, KeyPairProvider.ECDSA_SHA2_NISTP521); |
| addPublicKey(keys, p, KeyPairProvider.SSH_RSA); |
| addPublicKey(keys, p, KeyPairProvider.SSH_DSS); |
| } catch (IOException | GeneralSecurityException e) { |
| throw new IllegalStateException("Cannot load SSHD host key", e); |
| } |
| return keys; |
| } |
| |
| private static void addPublicKey(final Collection<PublicKey> out, KeyPairProvider p, String type) |
| throws IOException, GeneralSecurityException { |
| final KeyPair pair = p.loadKey(null, type); |
| if (pair != null && pair.getPublic() != null) { |
| out.add(pair.getPublic()); |
| } |
| } |
| |
| private String addressList() { |
| final StringBuilder r = new StringBuilder(); |
| for (Iterator<SocketAddress> i = listen.iterator(); i.hasNext(); ) { |
| r.append(SocketUtil.format(i.next(), IANA_SSH_PORT)); |
| if (i.hasNext()) { |
| r.append(", "); |
| } |
| } |
| return r.toString(); |
| } |
| |
| private void initKeyExchanges(Config cfg) { |
| List<KeyExchangeFactory> a = ServerBuilder.setUpDefaultKeyExchanges(true); |
| setKeyExchangeFactories(filter(cfg, "kex", a.toArray(new KeyExchangeFactory[a.size()]))); |
| } |
| |
| private void initProviderBouncyCastle(Config cfg) { |
| NamedFactory<Random> factory; |
| if (cfg.getBoolean("sshd", null, "testUseInsecureRandom", false)) { |
| factory = new InsecureBouncyCastleRandom.Factory(); |
| } else { |
| factory = SecurityUtils.getRandomFactory(); |
| } |
| setRandomFactory(new SingletonRandomFactory(factory)); |
| } |
| |
| private static class InsecureBouncyCastleRandom implements Random { |
| private static class Factory implements NamedFactory<Random> { |
| @Override |
| public String getName() { |
| return "INSECURE_bouncycastle"; |
| } |
| |
| @Override |
| public Random create() { |
| return new InsecureBouncyCastleRandom(); |
| } |
| } |
| |
| private final RandomGenerator random; |
| |
| private InsecureBouncyCastleRandom() { |
| random = new VMPCRandomGenerator(); |
| random.addSeedMaterial(1234); |
| } |
| |
| @Override |
| public String getName() { |
| return "InsecureBouncyCastleRandom"; |
| } |
| |
| @Override |
| public void fill(byte[] bytes, int start, int len) { |
| random.nextBytes(bytes, start, len); |
| } |
| |
| @Override |
| public void fill(byte[] bytes) { |
| random.nextBytes(bytes); |
| } |
| |
| @Override |
| public int random(int n) { |
| if (n > 0) { |
| if ((n & -n) == n) { |
| return (int) ((n * (long) next(31)) >> 31); |
| } |
| int bits; |
| int val; |
| do { |
| bits = next(31); |
| val = bits % n; |
| } while (bits - val + (n - 1) < 0); |
| return val; |
| } |
| throw new IllegalArgumentException(); |
| } |
| |
| protected final int next(int numBits) { |
| int bytes = (numBits + 7) / 8; |
| byte[] next = new byte[bytes]; |
| int ret = 0; |
| random.nextBytes(next); |
| for (int i = 0; i < bytes; i++) { |
| ret = (next[i] & 0xFF) | (ret << 8); |
| } |
| return ret >>> (bytes * 8 - numBits); |
| } |
| } |
| |
| @SuppressWarnings("unchecked") |
| private void initCiphers(Config cfg) { |
| List<NamedFactory<Cipher>> a = BaseBuilder.setUpDefaultCiphers(true); |
| |
| for (Iterator<NamedFactory<Cipher>> i = a.iterator(); i.hasNext(); ) { |
| NamedFactory<Cipher> f = i.next(); |
| try { |
| Cipher c = f.create(); |
| byte[] key = new byte[c.getKdfSize()]; |
| byte[] iv = new byte[c.getIVSize()]; |
| c.init(Cipher.Mode.Encrypt, key, iv); |
| } catch (InvalidKeyException e) { |
| logger.atWarning().log( |
| "Disabling cipher %s: %s; try installing unlimited cryptography extension", |
| f.getName(), e.getMessage()); |
| i.remove(); |
| } catch (Exception e) { |
| logger.atWarning().log("Disabling cipher %s: %s", f.getName(), e.getMessage()); |
| i.remove(); |
| } |
| } |
| |
| a.add(null); |
| setCipherFactories( |
| filter(cfg, "cipher", (NamedFactory<Cipher>[]) a.toArray(new NamedFactory<?>[a.size()]))); |
| } |
| |
| @SuppressWarnings("unchecked") |
| private void initMacs(Config cfg) { |
| List<NamedFactory<Mac>> m = BaseBuilder.setUpDefaultMacs(true); |
| setMacFactories( |
| filter(cfg, "mac", (NamedFactory<Mac>[]) m.toArray(new NamedFactory<?>[m.size()]))); |
| } |
| |
| @SafeVarargs |
| private static <T extends NamedResource> List<T> filter(Config cfg, String key, T... avail) { |
| List<T> def = new ArrayList<>(); |
| for (T n : avail) { |
| if (n == null) { |
| break; |
| } |
| def.add(n); |
| } |
| |
| String[] want = cfg.getStringList("sshd", null, key); |
| if (want == null || want.length == 0) { |
| return def; |
| } |
| |
| boolean didClear = false; |
| for (String setting : want) { |
| String name = setting.trim(); |
| boolean add = true; |
| if (name.startsWith("-")) { |
| add = false; |
| name = name.substring(1).trim(); |
| } else if (name.startsWith("+")) { |
| name = name.substring(1).trim(); |
| } else if (!didClear) { |
| didClear = true; |
| def.clear(); |
| } |
| |
| T n = find(name, avail); |
| if (n == null) { |
| StringBuilder msg = new StringBuilder(); |
| msg.append("sshd.").append(key).append(" = ").append(name).append(" unsupported; only "); |
| for (int i = 0; i < avail.length; i++) { |
| if (avail[i] == null) { |
| continue; |
| } |
| if (i > 0) { |
| msg.append(", "); |
| } |
| msg.append(avail[i].getName()); |
| } |
| msg.append(" is supported"); |
| logger.atSevere().log(msg.toString()); |
| } else if (add) { |
| if (!def.contains(n)) { |
| def.add(n); |
| } |
| } else { |
| def.remove(n); |
| } |
| } |
| |
| return def; |
| } |
| |
| @SafeVarargs |
| private static <T extends NamedResource> T find(String name, T... avail) { |
| for (T n : avail) { |
| if (n != null && name.equals(n.getName())) { |
| return n; |
| } |
| } |
| return null; |
| } |
| |
| private void initSignatures() { |
| setSignatureFactories(ServerBuilder.setUpDefaultSignatureFactories(false)); |
| } |
| |
| private void initCompression(boolean enableCompression) { |
| List<NamedFactory<Compression>> compressionFactories = new ArrayList<>(); |
| |
| // Always support no compression over SSHD. |
| compressionFactories.add(BuiltinCompressions.none); |
| |
| // In the general case, we want to disable transparent compression, since |
| // the majority of our data transfer is highly compressed Git pack files |
| // and we cannot make them any smaller than they already are. |
| // |
| // However, if there are CPU in abundance and the server is reachable through |
| // slow networks, gits with huge amount of refs can benefit from SSH-compression |
| // since git does not compress the ref announcement during the handshake. |
| // Compression can be especially useful when Gerrit replica are being used |
| // for the larger clones and fetches and the primary server handling write |
| // operations mostly takes small receive-packs. |
| |
| if (enableCompression) { |
| compressionFactories.add(BuiltinCompressions.zlib); |
| } |
| |
| setCompressionFactories(compressionFactories); |
| } |
| |
| private void initChannels() { |
| setChannelFactories(ServerBuilder.DEFAULT_CHANNEL_FACTORIES); |
| } |
| |
| private void initUnknownChannelReferenceHandler(boolean enableChannelIdTracking) { |
| setUnknownChannelReferenceHandler( |
| enableChannelIdTracking |
| ? ChannelIdTrackingUnknownChannelReferenceHandler.TRACKER |
| : DefaultUnknownChannelReferenceHandler.INSTANCE); |
| } |
| |
| private void initSubsystems() { |
| setSubsystemFactories(Collections.emptyList()); |
| } |
| |
| private void initUserAuth( |
| final PublickeyAuthenticator pubkey, |
| final GSSAuthenticator kerberosAuthenticator, |
| String kerberosKeytab, |
| String kerberosPrincipal) { |
| List<UserAuthFactory> authFactories = new ArrayList<>(); |
| if (kerberosKeytab != null) { |
| authFactories.add(UserAuthGSSFactory.INSTANCE); |
| logger.atInfo().log("Enabling kerberos with keytab %s", kerberosKeytab); |
| if (!new File(kerberosKeytab).canRead()) { |
| logger.atSevere().log( |
| "Keytab %s does not exist or is not readable; further errors are possible", |
| kerberosKeytab); |
| } |
| kerberosAuthenticator.setKeytabFile(kerberosKeytab); |
| if (kerberosPrincipal == null) { |
| try { |
| kerberosPrincipal = "host/" + InetAddress.getLocalHost().getCanonicalHostName(); |
| } catch (UnknownHostException e) { |
| kerberosPrincipal = "host/localhost"; |
| } |
| } |
| logger.atInfo().log("Using kerberos principal %s", kerberosPrincipal); |
| if (!kerberosPrincipal.startsWith("host/")) { |
| logger.atWarning().log( |
| "Host principal does not start with host/ " |
| + "which most SSH clients will supply automatically"); |
| } |
| kerberosAuthenticator.setServicePrincipalName(kerberosPrincipal); |
| setGSSAuthenticator(kerberosAuthenticator); |
| } |
| authFactories.add(UserAuthPublicKeyFactory.INSTANCE); |
| setUserAuthFactories(authFactories); |
| setPublickeyAuthenticator(pubkey); |
| } |
| |
| private void initForwarding() { |
| setForwardingFilter( |
| new ForwardingFilter() { |
| @Override |
| public boolean canForwardAgent(Session session, String requestType) { |
| return false; |
| } |
| |
| @Override |
| public boolean canForwardX11(Session session, String requestType) { |
| return false; |
| } |
| |
| @Override |
| public boolean canListen(SshdSocketAddress address, Session session) { |
| return false; |
| } |
| |
| @Override |
| public boolean canConnect(Type type, SshdSocketAddress address, Session session) { |
| return false; |
| } |
| }); |
| setForwarderFactory(new DefaultForwarderFactory()); |
| } |
| |
| private void initFileSystemFactory() { |
| setFileSystemFactory(NoneFileSystemFactory.INSTANCE); |
| } |
| } |
