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
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
|
// 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.entities.Account;
import com.google.gerrit.server.IdentifiedUser;
import com.google.gerrit.server.config.AnonymousCowardName;
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 java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.MalformedURLException;
import java.net.URL;
import org.apache.sshd.server.Environment;
import org.apache.sshd.server.ExitCallback;
import org.apache.sshd.server.SessionAware;
import org.apache.sshd.server.channel.ChannelSession;
import org.apache.sshd.server.command.Command;
import org.apache.sshd.server.session.ServerSession;
import org.apache.sshd.server.shell.ShellFactory;
import org.eclipse.jgit.lib.Constants;
import org.eclipse.jgit.util.SystemReader;
/**
* 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 ShellFactory {
private final Provider<SendMessage> shell;
@Inject
NoShell(Provider<SendMessage> shell) {
this.shell = shell;
}
@Override
public Command createShell(ChannelSession channel) {
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;
}
@Override
public void setInputStream(InputStream in) {
this.in = in;
}
@Override
public void setOutputStream(OutputStream out) {
this.out = out;
}
@Override
public void setErrorStream(OutputStream err) {
this.err = err;
}
@Override
public void setExitCallback(ExitCallback callback) {
this.exit = callback;
}
@Override
public void setSession(ServerSession session) {
SshSession s = session.getAttribute(SshSession.KEY);
this.context = sshScope.newContext(s, "");
}
@Override
public void start(ChannelSession channel, 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));
err.flush();
in.close();
out.close();
err.close();
exit.onExit(127);
}
@Override
public void destroy(ChannelSession channel) {}
}
static class MessageFactory {
private final IdentifiedUser user;
private final SshInfo sshInfo;
private final Provider<String> urlProvider;
private final String anonymousCowardName;
@Inject
MessageFactory(
IdentifiedUser user,
SshInfo sshInfo,
@CanonicalWebUrl Provider<String> urlProvider,
@AnonymousCowardName String anonymousCowardName) {
this.user = user;
this.sshInfo = sshInfo;
this.urlProvider = urlProvider;
this.anonymousCowardName = anonymousCowardName;
}
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.fullName();
if (name == null || name.isEmpty()) {
name = user.getUserName().orElse(anonymousCowardName);
}
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://");
if (user.getUserName().isPresent()) {
msg.append(user.getUserName().get());
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) {
// Ignored
}
}
return SystemReader.getInstance().getHostname();
}
}
}
|
