// Copyright (C) 2009 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.commands;
import static com.google.gerrit.sshd.CommandMetaData.Mode.MASTER_OR_SLAVE;
import com.google.gerrit.common.data.GlobalCapability;
import com.google.gerrit.extensions.annotations.RequiresCapability;
import com.google.gerrit.server.CurrentUser;
import com.google.gerrit.server.IdentifiedUser;
import com.google.gerrit.server.util.IdGenerator;
import com.google.gerrit.server.util.TimeUtil;
import com.google.gerrit.sshd.CommandMetaData;
import com.google.gerrit.sshd.SshCommand;
import com.google.gerrit.sshd.SshDaemon;
import com.google.gerrit.sshd.SshSession;
import com.google.inject.Inject;
import org.apache.sshd.common.io.IoAcceptor;
import org.apache.sshd.common.io.IoSession;
import org.apache.sshd.common.io.mina.MinaAcceptor;
import org.apache.sshd.common.io.mina.MinaSession;
import org.apache.sshd.common.io.nio2.Nio2Acceptor;
import org.apache.sshd.server.Environment;
import org.apache.sshd.server.session.ServerSession;
import org.kohsuke.args4j.Option;
import java.io.IOException;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.SocketAddress;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.Date;
import java.util.List;
/** Show the current SSH connections. */
@RequiresCapability(GlobalCapability.VIEW_CONNECTIONS)
@CommandMetaData(name = "show-connections", description = "Display active client SSH connections",
runsAt = MASTER_OR_SLAVE)
final class ShowConnections extends SshCommand {
@Option(name = "--numeric", aliases = {"-n"}, usage = "don't resolve names")
private boolean numeric;
@Option(name = "--wide", aliases = {"-w"}, usage = "display without line width truncation")
private boolean wide;
@Inject
private SshDaemon daemon;
private int hostNameWidth;
private int columns = 80;
@Override
public void start(final Environment env) throws IOException {
String s = env.getEnv().get(Environment.ENV_COLUMNS);
if (s != null && !s.isEmpty()) {
try {
columns = Integer.parseInt(s);
} catch (NumberFormatException err) {
columns = 80;
}
}
super.start(env);
}
@Override
protected void run() throws Failure {
final IoAcceptor acceptor = daemon.getIoAcceptor();
if (acceptor == null) {
throw new Failure(1, "fatal: sshd no longer running");
}
final List<IoSession> list =
new ArrayList<>(acceptor.getManagedSessions().values());
Collections.sort(list, new Comparator<IoSession>() {
@Override
public int compare(IoSession arg0, IoSession arg1) {
if (arg0 instanceof MinaSession) {
MinaSession mArg0 = (MinaSession) arg0;
MinaSession mArg1 = (MinaSession) arg1;
if (mArg0.getSession().getCreationTime() < mArg1.getSession()
.getCreationTime()) {
return -1;
} else if (mArg0.getSession().getCreationTime() > mArg1.getSession()
.getCreationTime()) {
return 1;
}
}
return (int) (arg0.getId() - arg1.getId());
}
});
hostNameWidth = wide ? Integer.MAX_VALUE : columns - 9 - 9 - 10 - 32;
final long now = TimeUtil.nowMs();
stdout.print(String.format("%-8s %8s %8s %-15s %s\n", //
"Session", "Start", "Idle", "User", "Remote Host"));
stdout.print("--------------------------------------------------------------\n");
for (final IoSession io : list) {
ServerSession s = (ServerSession) ServerSession.getSession(io, true);
SshSession sd = s != null ? s.getAttribute(SshSession.KEY) : null;
final SocketAddress remoteAddress = io.getRemoteAddress();
MinaSession minaSession = io instanceof MinaSession
? (MinaSession) io
: null;
final long start = minaSession == null
? 0
: minaSession.getSession().getCreationTime();
final long idle = minaSession == null
? now
: now - minaSession.getSession().getLastIoTime();
stdout.print(String.format("%8s %8s %8s %-15.15s %s\n", //
id(sd), //
time(now, start), //
age(idle), //
username(sd), //
hostname(remoteAddress)));
}
stdout.print("--\n");
stdout.print("SSHD Backend: " + getBackend() + "\n");
}
private String getBackend() {
IoAcceptor acceptor = daemon.getIoAcceptor();
if (acceptor == null) {
return "";
} else if (acceptor instanceof MinaAcceptor) {
return "mina";
} else if (acceptor instanceof Nio2Acceptor) {
return "nio2";
} else {
return "unknown";
}
}
private static String id(final SshSession sd) {
return sd != null ? IdGenerator.format(sd.getSessionId()) : "";
}
private static String time(final long now, final long time) {
if (time - now < 24 * 60 * 60 * 1000L) {
return new SimpleDateFormat("HH:mm:ss").format(new Date(time));
}
return new SimpleDateFormat("MMM-dd").format(new Date(time));
}
private static String age(long age) {
age /= 1000;
final int sec = (int) (age % 60);
age /= 60;
final int min = (int) (age % 60);
age /= 60;
final int hr = (int) (age % 60);
return String.format("%02d:%02d:%02d", hr, min, sec);
}
private String username(final SshSession sd) {
if (sd == null) {
return "";
}
final CurrentUser user = sd.getCurrentUser();
if (user != null && user.isIdentifiedUser()) {
IdentifiedUser u = (IdentifiedUser) user;
if (!numeric) {
String name = u.getAccount().getUserName();
if (name != null && !name.isEmpty()) {
return name;
}
}
return "a/" + u.getAccountId().toString();
} else {
return "";
}
}
private String hostname(final SocketAddress remoteAddress) {
if (remoteAddress == null) {
return "?";
}
String host = null;
if (remoteAddress instanceof InetSocketAddress) {
final InetSocketAddress sa = (InetSocketAddress) remoteAddress;
final InetAddress in = sa.getAddress();
if (numeric) {
return in.getHostAddress();
}
if (in != null) {
host = in.getCanonicalHostName();
} else {
host = sa.getHostName();
}
}
if (host == null) {
host = remoteAddress.toString();
}
if (host.length() > hostNameWidth) {
return host.substring(0, hostNameWidth);
}
return host;
}
}