// 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 com.google.gerrit.reviewdb.client.Account;
import com.google.gerrit.server.IdentifiedUser;
import com.google.gerrit.server.config.CanonicalWebUrl;
import com.google.gerrit.server.ssh.SshInfo;
import com.google.gerrit.sshd.SshScope.Context;
import com.google.inject.Inject;
import com.google.inject.Provider;
import org.apache.sshd.common.Factory;
import org.apache.sshd.server.Command;
import org.apache.sshd.server.Environment;
import org.apache.sshd.server.ExitCallback;
import org.apache.sshd.server.SessionAware;
import org.apache.sshd.server.session.ServerSession;
import org.eclipse.jgit.lib.Constants;
import org.eclipse.jgit.util.SystemReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.MalformedURLException;
import java.net.URL;
/**
* Dummy shell which prints a message and terminates.
* <p>
* This implementation is used to ensure clients who try to SSH directly to this
* server without supplying a command will get a reasonable error message, but
* cannot continue further.
*/
class NoShell implements Factory<Command> {
private final Provider<SendMessage> shell;
@Inject
NoShell(Provider<SendMessage> shell) {
this.shell = shell;
}
public Command create() {
return shell.get();
}
static class SendMessage implements Command, SessionAware {
private final Provider<MessageFactory> messageFactory;
private final SshScope sshScope;
private InputStream in;
private OutputStream out;
private OutputStream err;
private ExitCallback exit;
private Context context;
@Inject
SendMessage(Provider<MessageFactory> messageFactory, SshScope sshScope) {
this.messageFactory = messageFactory;
this.sshScope = sshScope;
}
public void setInputStream(final InputStream in) {
this.in = in;
}
public void setOutputStream(final OutputStream out) {
this.out = out;
}
public void setErrorStream(final OutputStream err) {
this.err = err;
}
public void setExitCallback(final ExitCallback callback) {
this.exit = callback;
}
public void setSession(final ServerSession session) {
this.context = sshScope.newContext(session.getAttribute(SshSession.KEY), "");
}
public void start(final Environment env) throws IOException {
Context old = sshScope.set(context);
String message;
try {
message = messageFactory.get().getMessage();
} finally {
sshScope.set(old);
}
err.write(Constants.encode(message.toString()));
err.flush();
in.close();
out.close();
err.close();
exit.onExit(127);
}
public void destroy() {
}
}
static class MessageFactory {
private final IdentifiedUser user;
private final SshInfo sshInfo;
private final Provider<String> urlProvider;
@Inject
MessageFactory(IdentifiedUser user, SshInfo sshInfo,
@CanonicalWebUrl Provider<String> urlProvider) {
this.user = user;
this.sshInfo = sshInfo;
this.urlProvider = urlProvider;
}
String getMessage() {
StringBuilder msg = new StringBuilder();
msg.append("\r\n");
msg.append(" **** Welcome to Gerrit Code Review ****\r\n");
msg.append("\r\n");
Account account = user.getAccount();
String name = account.getFullName();
if (name == null || name.isEmpty()) {
name = user.getUserName();
}
msg.append(" Hi ");
msg.append(name);
msg.append(", you have successfully connected over SSH.");
msg.append("\r\n");
msg.append("\r\n");
msg.append(" Unfortunately, interactive shells are disabled.\r\n");
msg.append(" To clone a hosted Git repository, use:\r\n");
msg.append("\r\n");
if (!sshInfo.getHostKeys().isEmpty()) {
String host = sshInfo.getHostKeys().get(0).getHost();
if (host.startsWith("*:")) {
host = getGerritHost() + host.substring(1);
}
msg.append(" git clone ssh://");
msg.append(user.getUserName());
msg.append("@");
msg.append(host);
msg.append("/");
msg.append("REPOSITORY_NAME.git");
msg.append("\r\n");
}
msg.append("\r\n");
return msg.toString();
}
private String getGerritHost() {
String url = urlProvider.get();
if (url != null) {
try {
return new URL(url).getHost();
} catch (MalformedURLException e) {
}
}
return SystemReader.getInstance().getHostname();
}
}
}