1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17
18 package org.apache.commons.net.imap;
19
20 import java.io.BufferedWriter;
21 import java.io.InputStreamReader;
22 import java.io.IOException;
23 import java.io.OutputStreamWriter;
24
25 import javax.net.ssl.KeyManager;
26 import javax.net.ssl.SSLContext;
27 import javax.net.ssl.SSLException;
28 import javax.net.ssl.SSLSocket;
29 import javax.net.ssl.SSLSocketFactory;
30 import javax.net.ssl.TrustManager;
31
32 import org.apache.commons.net.io.CRLFLineReader;
33 import org.apache.commons.net.util.SSLContextUtils;
34
35 /**
36 * The IMAPSClient class provides SSL/TLS connection encryption to IMAPClient.
37 * Copied from FTPSClient.java and modified to suit IMAP.
38 * If implicit mode is selected (NOT the default), SSL/TLS negotiation starts right
39 * after the connection has been established. In explicit mode (the default), SSL/TLS
40 * negotiation starts when the user calls execTLS() and the server accepts the command.
41 * Implicit usage:
42 * IMAPSClient c = new IMAPSClient(true);
43 * c.connect("127.0.0.1", 993);
44 * Explicit usage:
45 * IMAPSClient c = new IMAPSClient();
46 * c.connect("127.0.0.1", 143);
47 * if (c.execTLS()) { /rest of the commands here/ }
48 */
49 public class IMAPSClient extends IMAPClient
50 {
51 /** The default IMAP over SSL port. */
52 public static final int DEFAULT_IMAPS_PORT = 993;
53
54 /** Default secure socket protocol name. */
55 public static final String DEFAULT_PROTOCOL = "TLS";
56
57 /** The security mode. True - Implicit Mode / False - Explicit Mode. */
58 private final boolean isImplicit;
59 /** The secure socket protocol to be used, like SSL/TLS. */
60 private final String protocol;
61 /** The context object. */
62 private SSLContext context = null;
63 /** The cipher suites. SSLSockets have a default set of these anyway,
64 so no initialization required. */
65 private String[] suites = null;
66 /** The protocol versions. */
67 private String[] protocols = //null;
68 null;//{"SSLv2", "SSLv3", "TLSv1", "TLSv1.1", "SSLv2Hello"};
69
70 /** The IMAPS {@link TrustManager} implementation, default null. */
71 private TrustManager trustManager = null;
72
73 /** The {@link KeyManager}, default null. */
74 private KeyManager keyManager = null;
75
76 /**
77 * Constructor for IMAPSClient.
78 * Sets security mode to explicit (isImplicit = false).
79 */
80 public IMAPSClient()
81 {
82 this(DEFAULT_PROTOCOL, false);
83 }
84
85 /**
86 * Constructor for IMAPSClient.
87 * @param implicit The security mode (Implicit/Explicit).
88 */
89 public IMAPSClient(boolean implicit)
90 {
91 this(DEFAULT_PROTOCOL, implicit);
92 }
93
94 /**
95 * Constructor for IMAPSClient.
96 * @param proto the protocol.
97 */
98 public IMAPSClient(String proto)
99 {
100 this(proto, false);
101 }
102
103 /**
104 * Constructor for IMAPSClient.
105 * @param proto the protocol.
106 * @param implicit The security mode(Implicit/Explicit).
107 */
108 public IMAPSClient(String proto, boolean implicit)
109 {
110 this(proto, implicit, null);
111 }
112
113 /**
114 * Constructor for IMAPSClient.
115 * @param proto the protocol.
116 * @param implicit The security mode(Implicit/Explicit).
117 */
118 public IMAPSClient(String proto, boolean implicit, SSLContext ctx)
119 {
120 super();
121 setDefaultPort(DEFAULT_IMAPS_PORT);
122 protocol = proto;
123 isImplicit = implicit;
124 context = ctx;
125 }
126
127 /**
128 * Constructor for IMAPSClient.
129 * @param implicit The security mode(Implicit/Explicit).
130 * @param ctx A pre-configured SSL Context.
131 */
132 public IMAPSClient(boolean implicit, SSLContext ctx)
133 {
134 this(DEFAULT_PROTOCOL, implicit, ctx);
135 }
136
137 /**
138 * Constructor for IMAPSClient.
139 * @param context A pre-configured SSL Context.
140 */
141 public IMAPSClient(SSLContext context)
142 {
143 this(false, context);
144 }
145
146 /**
147 * Because there are so many connect() methods,
148 * the _connectAction_() method is provided as a means of performing
149 * some action immediately after establishing a connection,
150 * rather than reimplementing all of the connect() methods.
151 * @throws IOException If it is thrown by _connectAction_().
152 * @see org.apache.commons.net.SocketClient#_connectAction_()
153 */
154 @Override
155 protected void _connectAction_() throws IOException
156 {
157 // Implicit mode.
158 if (isImplicit) {
159 performSSLNegotiation();
160 }
161 super._connectAction_();
162 // Explicit mode - don't do anything. The user calls execTLS()
163 }
164
165 /**
166 * Performs a lazy init of the SSL context.
167 * @throws IOException When could not initialize the SSL context.
168 */
169 private void initSSLContext() throws IOException
170 {
171 if (context == null)
172 {
173 context = SSLContextUtils.createSSLContext(protocol, getKeyManager(), getTrustManager());
174 }
175 }
176
177 /**
178 * SSL/TLS negotiation. Acquires an SSL socket of a
179 * connection and carries out handshake processing.
180 * @throws IOException If server negotiation fails.
181 */
182 private void performSSLNegotiation() throws IOException
183 {
184 initSSLContext();
185
186 SSLSocketFactory ssf = context.getSocketFactory();
187 String ip = getRemoteAddress().getHostAddress();
188 int port = getRemotePort();
189 SSLSocket socket =
190 (SSLSocket) ssf.createSocket(_socket_, ip, port, true);
191 socket.setEnableSessionCreation(true);
192 socket.setUseClientMode(true);
193
194 if (protocols != null) {
195 socket.setEnabledProtocols(protocols);
196 }
197 if (suites != null) {
198 socket.setEnabledCipherSuites(suites);
199 }
200 socket.startHandshake();
201
202 _socket_ = socket;
203 _input_ = socket.getInputStream();
204 _output_ = socket.getOutputStream();
205 _reader =
206 new CRLFLineReader(new InputStreamReader(_input_,
207 __DEFAULT_ENCODING));
208 __writer =
209 new BufferedWriter(new OutputStreamWriter(_output_,
210 __DEFAULT_ENCODING));
211 }
212
213 /**
214 * Get the {@link KeyManager} instance.
215 * @return The current {@link KeyManager} instance.
216 */
217 private KeyManager getKeyManager()
218 {
219 return keyManager;
220 }
221
222 /**
223 * Set a {@link KeyManager} to use.
224 * @param newKeyManager The KeyManager implementation to set.
225 * @see org.apache.commons.net.util.KeyManagerUtils
226 */
227 public void setKeyManager(KeyManager newKeyManager)
228 {
229 keyManager = newKeyManager;
230 }
231
232 /**
233 * Controls which particular cipher suites are enabled for use on this
234 * connection. Called before server negotiation.
235 * @param cipherSuites The cipher suites.
236 */
237 public void setEnabledCipherSuites(String[] cipherSuites)
238 {
239 suites = new String[cipherSuites.length];
240 System.arraycopy(cipherSuites, 0, suites, 0, cipherSuites.length);
241 }
242
243 /**
244 * Returns the names of the cipher suites which could be enabled
245 * for use on this connection.
246 * When the underlying {@link java.net.Socket Socket} is not an {@link SSLSocket} instance, returns null.
247 * @return An array of cipher suite names, or <code>null</code>.
248 */
249 public String[] getEnabledCipherSuites()
250 {
251 if (_socket_ instanceof SSLSocket)
252 {
253 return ((SSLSocket)_socket_).getEnabledCipherSuites();
254 }
255 return null;
256 }
257
258 /**
259 * Controls which particular protocol versions are enabled for use on this
260 * connection. I perform setting before a server negotiation.
261 * @param protocolVersions The protocol versions.
262 */
263 public void setEnabledProtocols(String[] protocolVersions)
264 {
265 protocols = new String[protocolVersions.length];
266 System.arraycopy(protocolVersions, 0, protocols, 0, protocolVersions.length);
267 }
268
269 /**
270 * Returns the names of the protocol versions which are currently
271 * enabled for use on this connection.
272 * When the underlying {@link java.net.Socket Socket} is not an {@link SSLSocket} instance, returns null.
273 * @return An array of protocols, or <code>null</code>.
274 */
275 public String[] getEnabledProtocols()
276 {
277 if (_socket_ instanceof SSLSocket)
278 {
279 return ((SSLSocket)_socket_).getEnabledProtocols();
280 }
281 return null;
282 }
283
284 /**
285 * The TLS command execution.
286 * @throws SSLException If the server reply code is not positive.
287 * @throws IOException If an I/O error occurs while sending
288 * the command or performing the negotiation.
289 * @return TRUE if the command and negotiation succeeded.
290 */
291 public boolean execTLS() throws SSLException, IOException
292 {
293 if (sendCommand(IMAPCommand.getCommand(IMAPCommand.STARTTLS)) != IMAPReply.OK)
294 {
295 return false;
296 //throw new SSLException(getReplyString());
297 }
298 performSSLNegotiation();
299 return true;
300 }
301
302 /**
303 * Get the currently configured {@link TrustManager}.
304 * @return A TrustManager instance.
305 */
306 public TrustManager getTrustManager()
307 {
308 return trustManager;
309 }
310
311 /**
312 * Override the default {@link TrustManager} to use.
313 * @param newTrustManager The TrustManager implementation to set.
314 * @see org.apache.commons.net.util.TrustManagerUtils
315 */
316 public void setTrustManager(TrustManager newTrustManager)
317 {
318 trustManager = newTrustManager;
319 }
320
321 }
322 /* kate: indent-width 4; replace-tabs on; */