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1 /*
2  * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4  *
5  * This code is free software; you can redistribute it and/or modify it
6  * under the terms of the GNU General Public License version 2 only, as
7  * published by the Free Software Foundation.  Oracle designates this
8  * particular file as subject to the "Classpath" exception as provided
9  * by Oracle in the LICENSE file that accompanied this code.
10  *
11  * This code is distributed in the hope that it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14  * version 2 for more details (a copy is included in the LICENSE file that
15  * accompanied this code).
16  *
17  * You should have received a copy of the GNU General Public License version
18  * 2 along with this work; if not, write to the Free Software Foundation,
19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20  *
21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22  * or visit www.oracle.com if you need additional information or have any
23  * questions.
24  */
25 
26 package javax.net.ssl;
27 
28 import java.nio.ByteBuffer;
29 import java.nio.ReadOnlyBufferException;
30 
31 
32 /**
33  * A class which enables secure communications using protocols such as
34  * the Secure Sockets Layer (SSL) or
35  * <A HREF="http://www.ietf.org/rfc/rfc2246.txt"> IETF RFC 2246 "Transport
36  * Layer Security" (TLS) </A> protocols, but is transport independent.
37  * <P>
38  * The secure communications modes include: <UL>
39  *
40  *      <LI> <em>Integrity Protection</em>.  SSL/TLS protects against
41  *      modification of messages by an active wiretapper.
42  *
43  *      <LI> <em>Authentication</em>.  In most modes, SSL/TLS provides
44  *      peer authentication.  Servers are usually authenticated, and
45  *      clients may be authenticated as requested by servers.
46  *
47  *      <LI> <em>Confidentiality (Privacy Protection)</em>.  In most
48  *      modes, SSL/TLS encrypts data being sent between client and
49  *      server.  This protects the confidentiality of data, so that
50  *      passive wiretappers won't see sensitive data such as financial
51  *      information or personal information of many kinds.
52  *
53  *      </UL>
54  *
55  * These kinds of protection are specified by a "cipher suite", which
56  * is a combination of cryptographic algorithms used by a given SSL
57  * connection.  During the negotiation process, the two endpoints must
58  * agree on a cipher suite that is available in both environments.  If
59  * there is no such suite in common, no SSL connection can be
60  * established, and no data can be exchanged.
61  * <P>
62  * The cipher suite used is established by a negotiation process called
63  * "handshaking".  The goal of this process is to create or rejoin a
64  * "session", which may protect many connections over time.  After
65  * handshaking has completed, you can access session attributes by
66  * using the {@link #getSession()} method.
67  * <P>
68  * The <code>SSLSocket</code> class provides much of the same security
69  * functionality, but all of the inbound and outbound data is
70  * automatically transported using the underlying {@link
71  * java.net.Socket Socket}, which by design uses a blocking model.
72  * While this is appropriate for many applications, this model does not
73  * provide the scalability required by large servers.
74  * <P>
75  * The primary distinction of an <code>SSLEngine</code> is that it
76  * operates on inbound and outbound byte streams, independent of the
77  * transport mechanism.  It is the responsibility of the
78  * <code>SSLEngine</code> user to arrange for reliable I/O transport to
79  * the peer.  By separating the SSL/TLS abstraction from the I/O
80  * transport mechanism, the <code>SSLEngine</code> can be used for a
81  * wide variety of I/O types, such as {@link
82  * java.nio.channels.spi.AbstractSelectableChannel#configureBlocking(boolean)
83  * non-blocking I/O (polling)}, {@link java.nio.channels.Selector
84  * selectable non-blocking I/O}, {@link java.net.Socket Socket} and the
85  * traditional Input/OutputStreams, local {@link java.nio.ByteBuffer
86  * ByteBuffers} or byte arrays, <A
87  * HREF="http://www.jcp.org/en/jsr/detail?id=203"> future asynchronous
88  * I/O models </A>, and so on.
89  * <P>
90  * At a high level, the <code>SSLEngine</code> appears thus:
91  *
92  * <pre>
93  *                   app data
94  *
95  *                |           ^
96  *                |     |     |
97  *                v     |     |
98  *           +----+-----|-----+----+
99  *           |          |          |
100  *           |       SSL|Engine    |
101  *   wrap()  |          |          |  unwrap()
102  *           | OUTBOUND | INBOUND  |
103  *           |          |          |
104  *           +----+-----|-----+----+
105  *                |     |     ^
106  *                |     |     |
107  *                v           |
108  *
109  *                   net data
110  * </pre>
111  * Application data (also known as plaintext or cleartext) is data which
112  * is produced or consumed by an application.  Its counterpart is
113  * network data, which consists of either handshaking and/or ciphertext
114  * (encrypted) data, and destined to be transported via an I/O
115  * mechanism.  Inbound data is data which has been received from the
116  * peer, and outbound data is destined for the peer.
117  * <P>
118  * (In the context of an <code>SSLEngine</code>, the term "handshake
119  * data" is taken to mean any data exchanged to establish and control a
120  * secure connection.  Handshake data includes the SSL/TLS messages
121  * "alert", "change_cipher_spec," and "handshake.")
122  * <P>
123  * There are five distinct phases to an <code>SSLEngine</code>.
124  *
125  * <OL>
126  *     <li> Creation - The <code>SSLEngine</code> has been created and
127  *     initialized, but has not yet been used.  During this phase, an
128  *     application may set any <code>SSLEngine</code>-specific settings
129  *     (enabled cipher suites, whether the <code>SSLEngine</code> should
130  *     handshake in client or server mode, and so on).  Once
131  *     handshaking has begun, though, any new settings (except
132  *     client/server mode, see below) will be used for
133  *     the next handshake.
134  *
135  *     <li> Initial Handshake - The initial handshake is a procedure by
136  *     which the two peers exchange communication parameters until an
137  *     SSLSession is established.  Application data can not be sent during
138  *     this phase.
139  *
140  *     <li> Application Data - Once the communication parameters have
141  *     been established and the handshake is complete, application data
142  *     may flow through the <code>SSLEngine</code>.  Outbound
143  *     application messages are encrypted and integrity protected,
144  *     and inbound messages reverse the process.
145  *
146  *     <li>  Rehandshaking - Either side may request a renegotiation of
147  *     the session at any time during the Application Data phase.  New
148  *     handshaking data can be intermixed among the application data.
149  *     Before starting the rehandshake phase, the application may
150  *     reset the SSL/TLS communication parameters such as the list of
151  *     enabled ciphersuites and whether to use client authentication,
152  *     but can not change between client/server modes.  As before, once
153  *     handshaking has begun, any new <code>SSLEngine</code>
154  *     configuration settings will not be used until the next
155  *     handshake.
156  *
157  *     <li>  Closure - When the connection is no longer needed, the
158  *     application should close the <code>SSLEngine</code> and should
159  *     send/receive any remaining messages to the peer before
160  *     closing the underlying transport mechanism.  Once an engine is
161  *     closed, it is not reusable:  a new <code>SSLEngine</code> must
162  *     be created.
163  * </OL>
164  * An <code>SSLEngine</code> is created by calling {@link
165  * SSLContext#createSSLEngine()} from an initialized
166  * <code>SSLContext</code>.  Any configuration
167  * parameters should be set before making the first call to
168  * <code>wrap()</code>, <code>unwrap()</code>, or
169  * <code>beginHandshake()</code>.  These methods all trigger the
170  * initial handshake.
171  * <P>
172  * Data moves through the engine by calling {@link #wrap(ByteBuffer,
173  * ByteBuffer) wrap()} or {@link #unwrap(ByteBuffer, ByteBuffer)
174  * unwrap()} on outbound or inbound data, respectively.  Depending on
175  * the state of the <code>SSLEngine</code>, a <code>wrap()</code> call
176  * may consume application data from the source buffer and may produce
177  * network data in the destination buffer.  The outbound data
178  * may contain application and/or handshake data.  A call to
179  * <code>unwrap()</code> will examine the source buffer and may
180  * advance the handshake if the data is handshaking information, or
181  * may place application data in the destination buffer if the data
182  * is application.  The state of the underlying SSL/TLS algorithm
183  * will determine when data is consumed and produced.
184  * <P>
185  * Calls to <code>wrap()</code> and <code>unwrap()</code> return an
186  * <code>SSLEngineResult</code> which indicates the status of the
187  * operation, and (optionally) how to interact with the engine to make
188  * progress.
189  * <P>
190  * The <code>SSLEngine</code> produces/consumes complete SSL/TLS
191  * packets only, and does not store application data internally between
192  * calls to <code>wrap()/unwrap()</code>.  Thus input and output
193  * <code>ByteBuffer</code>s must be sized appropriately to hold the
194  * maximum record that can be produced.  Calls to {@link
195  * SSLSession#getPacketBufferSize()} and {@link
196  * SSLSession#getApplicationBufferSize()} should be used to determine
197  * the appropriate buffer sizes.  The size of the outbound application
198  * data buffer generally does not matter.  If buffer conditions do not
199  * allow for the proper consumption/production of data, the application
200  * must determine (via {@link SSLEngineResult}) and correct the
201  * problem, and then try the call again.
202  * <P>
203  * For example, <code>unwrap()</code> will return a {@link
204  * SSLEngineResult.Status#BUFFER_OVERFLOW} result if the engine
205  * determines that there is not enough destination buffer space available.
206  * Applications should call {@link SSLSession#getApplicationBufferSize()}
207  * and compare that value with the space available in the destination buffer,
208  * enlarging the buffer if necessary.  Similarly, if <code>unwrap()</code>
209  * were to return a {@link SSLEngineResult.Status#BUFFER_UNDERFLOW}, the
210  * application should call {@link SSLSession#getPacketBufferSize()} to ensure
211  * that the source buffer has enough room to hold a record (enlarging if
212  * necessary), and then obtain more inbound data.
213  *
214  * <pre>
215  *   SSLEngineResult r = engine.unwrap(src, dst);
216  *   switch (r.getStatus()) {
217  *   BUFFER_OVERFLOW:
218  *       // Could attempt to drain the dst buffer of any already obtained
219  *       // data, but we'll just increase it to the size needed.
220  *       int appSize = engine.getSession().getApplicationBufferSize();
221  *       ByteBuffer b = ByteBuffer.allocate(appSize + dst.position());
222  *       dst.flip();
223  *       b.put(dst);
224  *       dst = b;
225  *       // retry the operation.
226  *       break;
227  *   BUFFER_UNDERFLOW:
228  *       int netSize = engine.getSession().getPacketBufferSize();
229  *       // Resize buffer if needed.
230  *       if (netSize > dst.capacity()) {
231  *           ByteBuffer b = ByteBuffer.allocate(netSize);
232  *           src.flip();
233  *           b.put(src);
234  *           src = b;
235  *       }
236  *       // Obtain more inbound network data for src,
237  *       // then retry the operation.
238  *       break;
239  *   // other cases: CLOSED, OK.
240  *   }
241  * </pre>
242  *
243  * <P>
244  * Unlike <code>SSLSocket</code>, all methods of SSLEngine are
245  * non-blocking.  <code>SSLEngine</code> implementations may
246  * require the results of tasks that may take an extended period of
247  * time to complete, or may even block.  For example, a TrustManager
248  * may need to connect to a remote certificate validation service,
249  * or a KeyManager might need to prompt a user to determine which
250  * certificate to use as part of client authentication.  Additionally,
251  * creating cryptographic signatures and verifying them can be slow,
252  * seemingly blocking.
253  * <P>
254  * For any operation which may potentially block, the
255  * <code>SSLEngine</code> will create a {@link java.lang.Runnable}
256  * delegated task.  When <code>SSLEngineResult</code> indicates that a
257  * delegated task result is needed, the application must call {@link
258  * #getDelegatedTask()} to obtain an outstanding delegated task and
259  * call its {@link java.lang.Runnable#run() run()} method (possibly using
260  * a different thread depending on the compute strategy).  The
261  * application should continue obtaining delegated tasks until no more
262  * exist, and try the original operation again.
263  * <P>
264  * At the end of a communication session, applications should properly
265  * close the SSL/TLS link.  The SSL/TLS protocols have closure handshake
266  * messages, and these messages should be communicated to the peer
267  * before releasing the <code>SSLEngine</code> and closing the
268  * underlying transport mechanism.  A close can be initiated by one of:
269  * an SSLException, an inbound closure handshake message, or one of the
270  * close methods.  In all cases, closure handshake messages are
271  * generated by the engine, and <code>wrap()</code> should be repeatedly
272  * called until the resulting <code>SSLEngineResult</code>'s status
273  * returns "CLOSED", or {@link #isOutboundDone()} returns true.  All
274  * data obtained from the <code>wrap()</code> method should be sent to the
275  * peer.
276  * <P>
277  * {@link #closeOutbound()} is used to signal the engine that the
278  * application will not be sending any more data.
279  * <P>
280  * A peer will signal its intent to close by sending its own closure
281  * handshake message.  After this message has been received and
282  * processed by the local <code>SSLEngine</code>'s <code>unwrap()</code>
283  * call, the application can detect the close by calling
284  * <code>unwrap()</code> and looking for a <code>SSLEngineResult</code>
285  * with status "CLOSED", or if {@link #isInboundDone()} returns true.
286  * If for some reason the peer closes the communication link without
287  * sending the proper SSL/TLS closure message, the application can
288  * detect the end-of-stream and can signal the engine via {@link
289  * #closeInbound()} that there will no more inbound messages to
290  * process.  Some applications might choose to require orderly shutdown
291  * messages from a peer, in which case they can check that the closure
292  * was generated by a handshake message and not by an end-of-stream
293  * condition.
294  * <P>
295  * There are two groups of cipher suites which you will need to know
296  * about when managing cipher suites:
297  *
298  * <UL>
299  *      <LI> <em>Supported</em> cipher suites:  all the suites which are
300  *      supported by the SSL implementation.  This list is reported
301  *      using {@link #getSupportedCipherSuites()}.
302  *
303  *      <LI> <em>Enabled</em> cipher suites, which may be fewer than
304  *      the full set of supported suites.  This group is set using the
305  *      {@link #setEnabledCipherSuites(String [])} method, and
306  *      queried using the {@link #getEnabledCipherSuites()} method.
307  *      Initially, a default set of cipher suites will be enabled on a
308  *      new engine that represents the minimum suggested
309  *      configuration.
310  * </UL>
311  *
312  * Implementation defaults require that only cipher suites which
313  * authenticate servers and provide confidentiality be enabled by
314  * default.  Only if both sides explicitly agree to unauthenticated
315  * and/or non-private (unencrypted) communications will such a
316  * cipher suite be selected.
317  * <P>
318  * Each SSL/TLS connection must have one client and one server, thus
319  * each endpoint must decide which role to assume.  This choice determines
320  * who begins the handshaking process as well as which type of messages
321  * should be sent by each party.  The method {@link
322  * #setUseClientMode(boolean)} configures the mode.  Once the initial
323  * handshaking has started, an <code>SSLEngine</code> can not switch
324  * between client and server modes, even when performing renegotiations.
325  * <P>
326  * Applications might choose to process delegated tasks in different
327  * threads.  When an <code>SSLEngine</code>
328  * is created, the current {@link java.security.AccessControlContext}
329  * is saved.  All future delegated tasks will be processed using this
330  * context:  that is, all access control decisions will be made using the
331  * context captured at engine creation.
332  * <P>
333  * <HR>
334  *
335  * <B>Concurrency Notes</B>:
336  * There are two concurrency issues to be aware of:
337  *
338  * <OL>
339  *      <li>The <code>wrap()</code> and <code>unwrap()</code> methods
340  *      may execute concurrently of each other.
341  *
342  *      <li> The SSL/TLS protocols employ ordered packets.
343  *      Applications must take care to ensure that generated packets
344  *      are delivered in sequence.  If packets arrive
345  *      out-of-order, unexpected or fatal results may occur.
346  * <P>
347  *      For example:
348  * <P>
349  *      <pre>
350  *              synchronized (outboundLock) {
351  *                  sslEngine.wrap(src, dst);
352  *                  outboundQueue.put(dst);
353  *              }
354  *      </pre>
355  *
356  *      As a corollary, two threads must not attempt to call the same method
357  *      (either <code>wrap()</code> or <code>unwrap()</code>) concurrently,
358  *      because there is no way to guarantee the eventual packet ordering.
359  * </OL>
360  *
361  * <h3>Default configuration for different Android versions</h3>
362  * <p>{@code SSLEngine} instances obtained from default {@link SSLContext} are configured as
363  * follows:
364  *
365  * <style type="text/css">
366  *   tr.deprecated {
367  *     background-color: #ccc;
368  *     color: #999;
369  *     font-style: italic;
370  *   }
371  * </style>
372  *
373  * <h4>Protocols</h4>
374  * <table>
375  *     <thead>
376  *         <tr>
377  *             <th>Protocol</th>
378  *             <th>Supported (API Levels)</th>
379  *             <th>Enabled by default (API Levels)</th>
380  *         </tr>
381  *     </thead>
382  *     <tbody>
383  *         <tr>
384  *             <td>SSLv3</td>
385  *             <td>1+</td>
386  *             <td>1&ndash;22</td>
387  *         </tr>
388  *         <tr>
389  *             <td>TLSv1</td>
390  *             <td>1+</td>
391  *             <td>1+</td>
392  *         </tr>
393  *         <tr>
394  *             <td>TLSv1.1</td>
395  *             <td>20+</td>
396  *             <td>20+</td>
397  *         </tr>
398  *         <tr>
399  *             <td>TLSv1.2</td>
400  *             <td>20+</td>
401  *             <td>20+</td>
402  *         </tr>
403  *     </tbody>
404  * </table>
405  *
406  * <h4>Cipher suites</h4>
407  * <table>
408  *     <thead>
409  *         <tr>
410  *             <th>Cipher suite</th>
411  *             <th>Supported (API Levels)</th>
412  *             <th>Enabled by default (API Levels)</th>
413  *         </tr>
414  *     </thead>
415  *     <tbody>
416  *         <tr class="deprecated">
417  *             <td>SSL_DHE_DSS_EXPORT_WITH_DES40_CBC_SHA</td>
418  *             <td>9&ndash;22</td>
419  *             <td>9&ndash;19</td>
420  *         </tr>
421  *         <tr class="deprecated">
422  *             <td>SSL_DHE_DSS_WITH_3DES_EDE_CBC_SHA</td>
423  *             <td>9&ndash;22</td>
424  *             <td>9&ndash;19</td>
425  *         </tr>
426  *         <tr class="deprecated">
427  *             <td>SSL_DHE_DSS_WITH_DES_CBC_SHA</td>
428  *             <td>9&ndash;22</td>
429  *             <td>9&ndash;19</td>
430  *         </tr>
431  *         <tr class="deprecated">
432  *             <td>SSL_DHE_RSA_EXPORT_WITH_DES40_CBC_SHA</td>
433  *             <td>9&ndash;22</td>
434  *             <td>9&ndash;19</td>
435  *         </tr>
436  *         <tr class="deprecated">
437  *             <td>SSL_DHE_RSA_WITH_3DES_EDE_CBC_SHA</td>
438  *             <td>9&ndash;22</td>
439  *             <td>9&ndash;19</td>
440  *         </tr>
441  *         <tr class="deprecated">
442  *             <td>SSL_DHE_RSA_WITH_DES_CBC_SHA</td>
443  *             <td>9&ndash;22</td>
444  *             <td>9&ndash;19</td>
445  *         </tr>
446  *         <tr class="deprecated">
447  *             <td>SSL_DH_anon_EXPORT_WITH_DES40_CBC_SHA</td>
448  *             <td>9&ndash;22</td>
449  *             <td></td>
450  *         </tr>
451  *         <tr class="deprecated">
452  *             <td>SSL_DH_anon_EXPORT_WITH_RC4_40_MD5</td>
453  *             <td>9&ndash;22</td>
454  *             <td></td>
455  *         </tr>
456  *         <tr class="deprecated">
457  *             <td>SSL_DH_anon_WITH_3DES_EDE_CBC_SHA</td>
458  *             <td>9&ndash;22</td>
459  *             <td></td>
460  *         </tr>
461  *         <tr class="deprecated">
462  *             <td>SSL_DH_anon_WITH_DES_CBC_SHA</td>
463  *             <td>9&ndash;22</td>
464  *             <td></td>
465  *         </tr>
466  *         <tr class="deprecated">
467  *             <td>SSL_DH_anon_WITH_RC4_128_MD5</td>
468  *             <td>9&ndash;22</td>
469  *             <td></td>
470  *         </tr>
471  *         <tr class="deprecated">
472  *             <td>SSL_RSA_EXPORT_WITH_DES40_CBC_SHA</td>
473  *             <td>9&ndash;22</td>
474  *             <td>9&ndash;19</td>
475  *         </tr>
476  *         <tr class="deprecated">
477  *             <td>SSL_RSA_EXPORT_WITH_RC4_40_MD5</td>
478  *             <td>9&ndash;22</td>
479  *             <td>9&ndash;19</td>
480  *         </tr>
481  *         <tr>
482  *             <td>SSL_RSA_WITH_3DES_EDE_CBC_SHA</td>
483  *             <td>9+</td>
484  *             <td>9&ndash;19</td>
485  *         </tr>
486  *         <tr class="deprecated">
487  *             <td>SSL_RSA_WITH_DES_CBC_SHA</td>
488  *             <td>9&ndash;22</td>
489  *             <td>9&ndash;19</td>
490  *         </tr>
491  *         <tr class="deprecated">
492  *             <td>SSL_RSA_WITH_NULL_MD5</td>
493  *             <td>9&ndash;22</td>
494  *             <td></td>
495  *         </tr>
496  *         <tr class="deprecated">
497  *             <td>SSL_RSA_WITH_NULL_SHA</td>
498  *             <td>9&ndash;22</td>
499  *             <td></td>
500  *         </tr>
501  *         <tr>
502  *             <td>SSL_RSA_WITH_RC4_128_MD5</td>
503  *             <td>9+</td>
504  *             <td>9&ndash;19</td>
505  *         </tr>
506  *         <tr>
507  *             <td>SSL_RSA_WITH_RC4_128_SHA</td>
508  *             <td>9+</td>
509  *             <td>9&ndash;23</td>
510  *         </tr>
511  *         <tr class="deprecated">
512  *             <td>TLS_DHE_DSS_EXPORT_WITH_DES40_CBC_SHA</td>
513  *             <td>1&ndash;8</td>
514  *             <td>1&ndash;8</td>
515  *         </tr>
516  *         <tr class="deprecated">
517  *             <td>TLS_DHE_DSS_WITH_3DES_EDE_CBC_SHA</td>
518  *             <td>1&ndash;8</td>
519  *             <td>1&ndash;8</td>
520  *         </tr>
521  *         <tr class="deprecated">
522  *             <td>TLS_DHE_DSS_WITH_AES_128_CBC_SHA</td>
523  *             <td>9&ndash;22</td>
524  *             <td>9&ndash;22</td>
525  *         </tr>
526  *         <tr class="deprecated">
527  *             <td>TLS_DHE_DSS_WITH_AES_128_CBC_SHA256</td>
528  *             <td>20&ndash;22</td>
529  *             <td></td>
530  *         </tr>
531  *         <tr class="deprecated">
532  *             <td>TLS_DHE_DSS_WITH_AES_128_GCM_SHA256</td>
533  *             <td>20&ndash;22</td>
534  *             <td></td>
535  *         </tr>
536  *         <tr class="deprecated">
537  *             <td>TLS_DHE_DSS_WITH_AES_256_CBC_SHA</td>
538  *             <td>9&ndash;22</td>
539  *             <td>20&ndash;22</td>
540  *         </tr>
541  *         <tr class="deprecated">
542  *             <td>TLS_DHE_DSS_WITH_AES_256_CBC_SHA256</td>
543  *             <td>20&ndash;22</td>
544  *             <td></td>
545  *         </tr>
546  *         <tr class="deprecated">
547  *             <td>TLS_DHE_DSS_WITH_AES_256_GCM_SHA384</td>
548  *             <td>20&ndash;22</td>
549  *             <td></td>
550  *         </tr>
551  *         <tr class="deprecated">
552  *             <td>TLS_DHE_DSS_WITH_DES_CBC_SHA</td>
553  *             <td>1&ndash;8</td>
554  *             <td>1&ndash;8</td>
555  *         </tr>
556  *         <tr class="deprecated">
557  *             <td>TLS_DHE_RSA_EXPORT_WITH_DES40_CBC_SHA</td>
558  *             <td>1&ndash;8</td>
559  *             <td>1&ndash;8</td>
560  *         </tr>
561  *         <tr class="deprecated">
562  *             <td>TLS_DHE_RSA_WITH_3DES_EDE_CBC_SHA</td>
563  *             <td>1&ndash;8</td>
564  *             <td>1&ndash;8</td>
565  *         </tr>
566  *         <tr>
567  *             <td>TLS_DHE_RSA_WITH_AES_128_CBC_SHA</td>
568  *             <td>9+</td>
569  *             <td>9+</td>
570  *         </tr>
571  *         <tr>
572  *             <td>TLS_DHE_RSA_WITH_AES_128_CBC_SHA256</td>
573  *             <td>20+</td>
574  *             <td></td>
575  *         </tr>
576  *         <tr>
577  *             <td>TLS_DHE_RSA_WITH_AES_128_GCM_SHA256</td>
578  *             <td>20+</td>
579  *             <td>20+</td>
580  *         </tr>
581  *         <tr>
582  *             <td>TLS_DHE_RSA_WITH_AES_256_CBC_SHA</td>
583  *             <td>9+</td>
584  *             <td>20+</td>
585  *         </tr>
586  *         <tr>
587  *             <td>TLS_DHE_RSA_WITH_AES_256_CBC_SHA256</td>
588  *             <td>20+</td>
589  *             <td></td>
590  *         </tr>
591  *         <tr>
592  *             <td>TLS_DHE_RSA_WITH_AES_256_GCM_SHA384</td>
593  *             <td>20+</td>
594  *             <td>20+</td>
595  *         </tr>
596  *         <tr class="deprecated">
597  *             <td>TLS_DHE_RSA_WITH_DES_CBC_SHA</td>
598  *             <td>1&ndash;8</td>
599  *             <td>1&ndash;8</td>
600  *         </tr>
601  *         <tr class="deprecated">
602  *             <td>TLS_DH_DSS_EXPORT_WITH_DES40_CBC_SHA</td>
603  *             <td>1&ndash;8</td>
604  *             <td></td>
605  *         </tr>
606  *         <tr class="deprecated">
607  *             <td>TLS_DH_DSS_WITH_3DES_EDE_CBC_SHA</td>
608  *             <td>1&ndash;8</td>
609  *             <td></td>
610  *         </tr>
611  *         <tr class="deprecated">
612  *             <td>TLS_DH_DSS_WITH_DES_CBC_SHA</td>
613  *             <td>1&ndash;8</td>
614  *             <td></td>
615  *         </tr>
616  *         <tr class="deprecated">
617  *             <td>TLS_DH_RSA_EXPORT_WITH_DES40_CBC_SHA</td>
618  *             <td>1&ndash;8</td>
619  *             <td></td>
620  *         </tr>
621  *         <tr class="deprecated">
622  *             <td>TLS_DH_RSA_WITH_3DES_EDE_CBC_SHA</td>
623  *             <td>1&ndash;8</td>
624  *             <td></td>
625  *         </tr>
626  *         <tr class="deprecated">
627  *             <td>TLS_DH_RSA_WITH_DES_CBC_SHA</td>
628  *             <td>1&ndash;8</td>
629  *             <td></td>
630  *         </tr>
631  *         <tr class="deprecated">
632  *             <td>TLS_DH_anon_EXPORT_WITH_DES40_CBC_SHA</td>
633  *             <td>1&ndash;8</td>
634  *             <td></td>
635  *         </tr>
636  *         <tr class="deprecated">
637  *             <td>TLS_DH_anon_WITH_3DES_EDE_CBC_SHA</td>
638  *             <td>1&ndash;8</td>
639  *             <td></td>
640  *         </tr>
641  *         <tr class="deprecated">
642  *             <td>TLS_DH_anon_WITH_AES_128_CBC_SHA</td>
643  *             <td>9&ndash;22</td>
644  *             <td></td>
645  *         </tr>
646  *         <tr class="deprecated">
647  *             <td>TLS_DH_anon_WITH_AES_128_CBC_SHA256</td>
648  *             <td>20&ndash;22</td>
649  *             <td></td>
650  *         </tr>
651  *         <tr class="deprecated">
652  *             <td>TLS_DH_anon_WITH_AES_128_GCM_SHA256</td>
653  *             <td>20&ndash;22</td>
654  *             <td></td>
655  *         </tr>
656  *         <tr class="deprecated">
657  *             <td>TLS_DH_anon_WITH_AES_256_CBC_SHA</td>
658  *             <td>9&ndash;22</td>
659  *             <td></td>
660  *         </tr>
661  *         <tr class="deprecated">
662  *             <td>TLS_DH_anon_WITH_AES_256_CBC_SHA256</td>
663  *             <td>20&ndash;22</td>
664  *             <td></td>
665  *         </tr>
666  *         <tr class="deprecated">
667  *             <td>TLS_DH_anon_WITH_AES_256_GCM_SHA384</td>
668  *             <td>20&ndash;22</td>
669  *             <td></td>
670  *         </tr>
671  *         <tr class="deprecated">
672  *             <td>TLS_DH_anon_WITH_DES_CBC_SHA</td>
673  *             <td>1&ndash;8</td>
674  *             <td></td>
675  *         </tr>
676  *         <tr class="deprecated">
677  *             <td>TLS_ECDHE_ECDSA_WITH_3DES_EDE_CBC_SHA</td>
678  *             <td>20&ndash;22</td>
679  *             <td></td>
680  *         </tr>
681  *         <tr>
682  *             <td>TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA</td>
683  *             <td>20+</td>
684  *             <td>20+</td>
685  *         </tr>
686  *         <tr>
687  *             <td>TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256</td>
688  *             <td>20+</td>
689  *             <td></td>
690  *         </tr>
691  *         <tr>
692  *             <td>TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256</td>
693  *             <td>20+</td>
694  *             <td>20+</td>
695  *         </tr>
696  *         <tr>
697  *             <td>TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA</td>
698  *             <td>20+</td>
699  *             <td>20+</td>
700  *         </tr>
701  *         <tr>
702  *             <td>TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384</td>
703  *             <td>20+</td>
704  *             <td></td>
705  *         </tr>
706  *         <tr>
707  *             <td>TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384</td>
708  *             <td>20+</td>
709  *             <td>20+</td>
710  *         </tr>
711  *         <tr>
712  *             <td>TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256</td>
713  *             <td>24+</td>
714  *             <td>24+</td>
715  *         </tr>
716  *         <tr class="deprecated">
717  *             <td>TLS_ECDHE_ECDSA_WITH_NULL_SHA</td>
718  *             <td>20&ndash;22</td>
719  *             <td></td>
720  *         </tr>
721  *         <tr>
722  *             <td>TLS_ECDHE_ECDSA_WITH_RC4_128_SHA</td>
723  *             <td>20+</td>
724  *             <td>20&ndash;23</td>
725  *         </tr>
726  *         <tr>
727  *             <td>TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA</td>
728  *             <td>21+</td>
729  *             <td>21+</td>
730  *         </tr>
731  *         <tr>
732  *             <td>TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA</td>
733  *             <td>21+</td>
734  *             <td>21+</td>
735  *         </tr>
736  *         <tr>
737  *             <td>TLS_ECDHE_PSK_WITH_CHACHA20_POLY1305_SHA256</td>
738  *             <td>24+</td>
739  *             <td>24+</td>
740  *         </tr>
741  *         <tr class="deprecated">
742  *             <td>TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA</td>
743  *             <td>20&ndash;22</td>
744  *             <td></td>
745  *         </tr>
746  *         <tr>
747  *             <td>TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA</td>
748  *             <td>20+</td>
749  *             <td>20+</td>
750  *         </tr>
751  *         <tr>
752  *             <td>TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256</td>
753  *             <td>20+</td>
754  *             <td></td>
755  *         </tr>
756  *         <tr>
757  *             <td>TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256</td>
758  *             <td>20+</td>
759  *             <td>20+</td>
760  *         </tr>
761  *         <tr>
762  *             <td>TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA</td>
763  *             <td>20+</td>
764  *             <td>20+</td>
765  *         </tr>
766  *         <tr>
767  *             <td>TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384</td>
768  *             <td>20+</td>
769  *             <td></td>
770  *         </tr>
771  *         <tr>
772  *             <td>TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384</td>
773  *             <td>20+</td>
774  *             <td>20+</td>
775  *         </tr>
776  *         <tr>
777  *             <td>TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256</td>
778  *             <td>24+</td>
779  *             <td>24+</td>
780  *         </tr>
781  *         <tr class="deprecated">
782  *             <td>TLS_ECDHE_RSA_WITH_NULL_SHA</td>
783  *             <td>20&ndash;22</td>
784  *             <td></td>
785  *         </tr>
786  *         <tr>
787  *             <td>TLS_ECDHE_RSA_WITH_RC4_128_SHA</td>
788  *             <td>20+</td>
789  *             <td>20&ndash;23</td>
790  *         </tr>
791  *         <tr class="deprecated">
792  *             <td>TLS_ECDH_ECDSA_WITH_3DES_EDE_CBC_SHA</td>
793  *             <td>20&ndash;22</td>
794  *             <td></td>
795  *         </tr>
796  *         <tr class="deprecated">
797  *             <td>TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA</td>
798  *             <td>20&ndash;22</td>
799  *             <td></td>
800  *         </tr>
801  *         <tr class="deprecated">
802  *             <td>TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA256</td>
803  *             <td>20&ndash;22</td>
804  *             <td></td>
805  *         </tr>
806  *         <tr class="deprecated">
807  *             <td>TLS_ECDH_ECDSA_WITH_AES_128_GCM_SHA256</td>
808  *             <td>20&ndash;22</td>
809  *             <td></td>
810  *         </tr>
811  *         <tr class="deprecated">
812  *             <td>TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA</td>
813  *             <td>20&ndash;22</td>
814  *             <td></td>
815  *         </tr>
816  *         <tr class="deprecated">
817  *             <td>TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA384</td>
818  *             <td>20&ndash;22</td>
819  *             <td></td>
820  *         </tr>
821  *         <tr class="deprecated">
822  *             <td>TLS_ECDH_ECDSA_WITH_AES_256_GCM_SHA384</td>
823  *             <td>20&ndash;22</td>
824  *             <td></td>
825  *         </tr>
826  *         <tr class="deprecated">
827  *             <td>TLS_ECDH_ECDSA_WITH_NULL_SHA</td>
828  *             <td>20&ndash;22</td>
829  *             <td></td>
830  *         </tr>
831  *         <tr class="deprecated">
832  *             <td>TLS_ECDH_ECDSA_WITH_RC4_128_SHA</td>
833  *             <td>20&ndash;22</td>
834  *             <td></td>
835  *         </tr>
836  *         <tr class="deprecated">
837  *             <td>TLS_ECDH_RSA_WITH_3DES_EDE_CBC_SHA</td>
838  *             <td>20&ndash;22</td>
839  *             <td></td>
840  *         </tr>
841  *         <tr class="deprecated">
842  *             <td>TLS_ECDH_RSA_WITH_AES_128_CBC_SHA</td>
843  *             <td>20&ndash;22</td>
844  *             <td></td>
845  *         </tr>
846  *         <tr class="deprecated">
847  *             <td>TLS_ECDH_RSA_WITH_AES_128_CBC_SHA256</td>
848  *             <td>20&ndash;22</td>
849  *             <td></td>
850  *         </tr>
851  *         <tr class="deprecated">
852  *             <td>TLS_ECDH_RSA_WITH_AES_128_GCM_SHA256</td>
853  *             <td>20&ndash;22</td>
854  *             <td></td>
855  *         </tr>
856  *         <tr class="deprecated">
857  *             <td>TLS_ECDH_RSA_WITH_AES_256_CBC_SHA</td>
858  *             <td>20&ndash;22</td>
859  *             <td></td>
860  *         </tr>
861  *         <tr class="deprecated">
862  *             <td>TLS_ECDH_RSA_WITH_AES_256_CBC_SHA384</td>
863  *             <td>20&ndash;22</td>
864  *             <td></td>
865  *         </tr>
866  *         <tr class="deprecated">
867  *             <td>TLS_ECDH_RSA_WITH_AES_256_GCM_SHA384</td>
868  *             <td>20&ndash;22</td>
869  *             <td></td>
870  *         </tr>
871  *         <tr class="deprecated">
872  *             <td>TLS_ECDH_RSA_WITH_NULL_SHA</td>
873  *             <td>20&ndash;22</td>
874  *             <td></td>
875  *         </tr>
876  *         <tr class="deprecated">
877  *             <td>TLS_ECDH_RSA_WITH_RC4_128_SHA</td>
878  *             <td>20&ndash;22</td>
879  *             <td></td>
880  *         </tr>
881  *         <tr class="deprecated">
882  *             <td>TLS_ECDH_anon_WITH_3DES_EDE_CBC_SHA</td>
883  *             <td>20&ndash;22</td>
884  *             <td></td>
885  *         </tr>
886  *         <tr class="deprecated">
887  *             <td>TLS_ECDH_anon_WITH_AES_128_CBC_SHA</td>
888  *             <td>20&ndash;22</td>
889  *             <td></td>
890  *         </tr>
891  *         <tr class="deprecated">
892  *             <td>TLS_ECDH_anon_WITH_AES_256_CBC_SHA</td>
893  *             <td>20&ndash;22</td>
894  *             <td></td>
895  *         </tr>
896  *         <tr class="deprecated">
897  *             <td>TLS_ECDH_anon_WITH_NULL_SHA</td>
898  *             <td>20&ndash;22</td>
899  *             <td></td>
900  *         </tr>
901  *         <tr class="deprecated">
902  *             <td>TLS_ECDH_anon_WITH_RC4_128_SHA</td>
903  *             <td>20&ndash;22</td>
904  *             <td></td>
905  *         </tr>
906  *         <tr>
907  *             <td>TLS_EMPTY_RENEGOTIATION_INFO_SCSV</td>
908  *             <td>20+</td>
909  *             <td>20+</td>
910  *         </tr>
911  *         <tr>
912  *             <td>TLS_FALLBACK_SCSV</td>
913  *             <td>21+</td>
914  *             <td></td>
915  *         </tr>
916  *         <tr class="deprecated">
917  *             <td>TLS_NULL_WITH_NULL_NULL</td>
918  *             <td>1&ndash;8</td>
919  *             <td></td>
920  *         </tr>
921  *         <tr class="deprecated">
922  *             <td>TLS_PSK_WITH_3DES_EDE_CBC_SHA</td>
923  *             <td>21&ndash;22</td>
924  *             <td></td>
925  *         </tr>
926  *         <tr>
927  *             <td>TLS_PSK_WITH_AES_128_CBC_SHA</td>
928  *             <td>21+</td>
929  *             <td>21+</td>
930  *         </tr>
931  *         <tr>
932  *             <td>TLS_PSK_WITH_AES_256_CBC_SHA</td>
933  *             <td>21+</td>
934  *             <td>21+</td>
935  *         </tr>
936  *         <tr>
937  *             <td>TLS_PSK_WITH_RC4_128_SHA</td>
938  *             <td>21+</td>
939  *             <td></td>
940  *         </tr>
941  *         <tr class="deprecated">
942  *             <td>TLS_RSA_EXPORT_WITH_DES40_CBC_SHA</td>
943  *             <td>1&ndash;8</td>
944  *             <td>1&ndash;8</td>
945  *         </tr>
946  *         <tr class="deprecated">
947  *             <td>TLS_RSA_WITH_3DES_EDE_CBC_SHA</td>
948  *             <td>1&ndash;8</td>
949  *             <td>1&ndash;8</td>
950  *         </tr>
951  *         <tr>
952  *             <td>TLS_RSA_WITH_AES_128_CBC_SHA</td>
953  *             <td>9+</td>
954  *             <td>9+</td>
955  *         </tr>
956  *         <tr>
957  *             <td>TLS_RSA_WITH_AES_128_CBC_SHA256</td>
958  *             <td>20+</td>
959  *             <td></td>
960  *         </tr>
961  *         <tr>
962  *             <td>TLS_RSA_WITH_AES_128_GCM_SHA256</td>
963  *             <td>20+</td>
964  *             <td>20+</td>
965  *         </tr>
966  *         <tr>
967  *             <td>TLS_RSA_WITH_AES_256_CBC_SHA</td>
968  *             <td>9+</td>
969  *             <td>20+</td>
970  *         </tr>
971  *         <tr>
972  *             <td>TLS_RSA_WITH_AES_256_CBC_SHA256</td>
973  *             <td>20+</td>
974  *             <td></td>
975  *         </tr>
976  *         <tr>
977  *             <td>TLS_RSA_WITH_AES_256_GCM_SHA384</td>
978  *             <td>20+</td>
979  *             <td>20+</td>
980  *         </tr>
981  *         <tr class="deprecated">
982  *             <td>TLS_RSA_WITH_DES_CBC_SHA</td>
983  *             <td>1&ndash;8</td>
984  *             <td>1&ndash;8</td>
985  *         </tr>
986  *         <tr class="deprecated">
987  *             <td>TLS_RSA_WITH_NULL_MD5</td>
988  *             <td>1&ndash;8</td>
989  *             <td></td>
990  *         </tr>
991  *         <tr class="deprecated">
992  *             <td>TLS_RSA_WITH_NULL_SHA</td>
993  *             <td>1&ndash;8</td>
994  *             <td></td>
995  *         </tr>
996  *         <tr class="deprecated">
997  *             <td>TLS_RSA_WITH_NULL_SHA256</td>
998  *             <td>20&ndash;22</td>
999  *             <td></td>
1000  *         </tr>
1001  *     </tbody>
1002  * </table>
1003  *
1004  * <p><em>NOTE</em>: PSK cipher suites are enabled by default only if the {@code SSLContext} through
1005  * which the engine was created has been initialized with a {@code PSKKeyManager}.
1006  *
1007  * @see SSLContext
1008  * @see SSLSocket
1009  * @see SSLServerSocket
1010  * @see SSLSession
1011  * @see java.net.Socket
1012  *
1013  * @since 1.5
1014  * @author Brad R. Wetmore
1015  */
1016 
1017 public abstract class SSLEngine {
1018 
1019     private String peerHost = null;
1020     private int peerPort = -1;
1021 
1022     /**
1023      * Constructor for an <code>SSLEngine</code> providing no hints
1024      * for an internal session reuse strategy.
1025      *
1026      * @see     SSLContext#createSSLEngine()
1027      * @see     SSLSessionContext
1028      */
SSLEngine()1029     protected SSLEngine() {
1030     }
1031 
1032     /**
1033      * Constructor for an <code>SSLEngine</code>.
1034      * <P>
1035      * <code>SSLEngine</code> implementations may use the
1036      * <code>peerHost</code> and <code>peerPort</code> parameters as hints
1037      * for their internal session reuse strategy.
1038      * <P>
1039      * Some cipher suites (such as Kerberos) require remote hostname
1040      * information. Implementations of this class should use this
1041      * constructor to use Kerberos.
1042      * <P>
1043      * The parameters are not authenticated by the
1044      * <code>SSLEngine</code>.
1045      *
1046      * @param   peerHost the name of the peer host
1047      * @param   peerPort the port number of the peer
1048      * @see     SSLContext#createSSLEngine(String, int)
1049      * @see     SSLSessionContext
1050      */
SSLEngine(String peerHost, int peerPort)1051     protected SSLEngine(String peerHost, int peerPort) {
1052         this.peerHost = peerHost;
1053         this.peerPort = peerPort;
1054     }
1055 
1056     /**
1057      * Returns the host name of the peer.
1058      * <P>
1059      * Note that the value is not authenticated, and should not be
1060      * relied upon.
1061      *
1062      * @return  the host name of the peer, or null if nothing is
1063      *          available.
1064      */
getPeerHost()1065     public String getPeerHost() {
1066         return peerHost;
1067     }
1068 
1069     /**
1070      * Returns the port number of the peer.
1071      * <P>
1072      * Note that the value is not authenticated, and should not be
1073      * relied upon.
1074      *
1075      * @return  the port number of the peer, or -1 if nothing is
1076      *          available.
1077      */
getPeerPort()1078     public int getPeerPort() {
1079         return peerPort;
1080     }
1081 
1082     /**
1083      * Attempts to encode a buffer of plaintext application data into
1084      * SSL/TLS network data.
1085      * <P>
1086      * An invocation of this method behaves in exactly the same manner
1087      * as the invocation:
1088      * <blockquote><pre>
1089      * {@link #wrap(ByteBuffer [], int, int, ByteBuffer)
1090      *     engine.wrap(new ByteBuffer [] { src }, 0, 1, dst);}
1091      * </pre</blockquote>
1092      *
1093      * @param   src
1094      *          a <code>ByteBuffer</code> containing outbound application data
1095      * @param   dst
1096      *          a <code>ByteBuffer</code> to hold outbound network data
1097      * @return  an <code>SSLEngineResult</code> describing the result
1098      *          of this operation.
1099      * @throws  SSLException
1100      *          A problem was encountered while processing the
1101      *          data that caused the <code>SSLEngine</code> to abort.
1102      *          See the class description for more information on
1103      *          engine closure.
1104      * @throws  ReadOnlyBufferException
1105      *          if the <code>dst</code> buffer is read-only.
1106      * @throws  IllegalArgumentException
1107      *          if either <code>src</code> or <code>dst</code>
1108      *          is null.
1109      * @throws  IllegalStateException if the client/server mode
1110      *          has not yet been set.
1111      * @see     #wrap(ByteBuffer [], int, int, ByteBuffer)
1112      */
wrap(ByteBuffer src, ByteBuffer dst)1113     public SSLEngineResult wrap(ByteBuffer src,
1114             ByteBuffer dst) throws SSLException {
1115         return wrap(new ByteBuffer [] { src }, 0, 1, dst);
1116     }
1117 
1118     /**
1119      * Attempts to encode plaintext bytes from a sequence of data
1120      * buffers into SSL/TLS network data.
1121      * <P>
1122      * An invocation of this method behaves in exactly the same manner
1123      * as the invocation:
1124      * <blockquote><pre>
1125      * {@link #wrap(ByteBuffer [], int, int, ByteBuffer)
1126      *     engine.wrap(srcs, 0, srcs.length, dst);}
1127      * </pre</blockquote>
1128      *
1129      * @param   srcs
1130      *          an array of <code>ByteBuffers</code> containing the
1131      *          outbound application data
1132      * @param   dst
1133      *          a <code>ByteBuffer</code> to hold outbound network data
1134      * @return  an <code>SSLEngineResult</code> describing the result
1135      *          of this operation.
1136      * @throws  SSLException
1137      *          A problem was encountered while processing the
1138      *          data that caused the <code>SSLEngine</code> to abort.
1139      *          See the class description for more information on
1140      *          engine closure.
1141      * @throws  ReadOnlyBufferException
1142      *          if the <code>dst</code> buffer is read-only.
1143      * @throws  IllegalArgumentException
1144      *          if either <code>srcs</code> or <code>dst</code>
1145      *          is null, or if any element in <code>srcs</code> is null.
1146      * @throws  IllegalStateException if the client/server mode
1147      *          has not yet been set.
1148      * @see     #wrap(ByteBuffer [], int, int, ByteBuffer)
1149      */
wrap(ByteBuffer [] srcs, ByteBuffer dst)1150     public SSLEngineResult wrap(ByteBuffer [] srcs,
1151             ByteBuffer dst) throws SSLException {
1152         if (srcs == null) {
1153             throw new IllegalArgumentException("src == null");
1154         }
1155         return wrap(srcs, 0, srcs.length, dst);
1156     }
1157 
1158 
1159     /**
1160      * Attempts to encode plaintext bytes from a subsequence of data
1161      * buffers into SSL/TLS network data.  This <i>"gathering"</i>
1162      * operation encodes, in a single invocation, a sequence of bytes
1163      * from one or more of a given sequence of buffers.  Gathering
1164      * wraps are often useful when implementing network protocols or
1165      * file formats that, for example, group data into segments
1166      * consisting of one or more fixed-length headers followed by a
1167      * variable-length body.  See
1168      * {@link java.nio.channels.GatheringByteChannel} for more
1169      * information on gathering, and {@link
1170      * java.nio.channels.GatheringByteChannel#write(ByteBuffer[],
1171      * int, int)} for more information on the subsequence
1172      * behavior.
1173      * <P>
1174      * Depending on the state of the SSLEngine, this method may produce
1175      * network data without consuming any application data (for example,
1176      * it may generate handshake data.)
1177      * <P>
1178      * The application is responsible for reliably transporting the
1179      * network data to the peer, and for ensuring that data created by
1180      * multiple calls to wrap() is transported in the same order in which
1181      * it was generated.  The application must properly synchronize
1182      * multiple calls to this method.
1183      * <P>
1184      * If this <code>SSLEngine</code> has not yet started its initial
1185      * handshake, this method will automatically start the handshake.
1186      * <P>
1187      * This method will attempt to produce one SSL/TLS packet, and will
1188      * consume as much source data as possible, but will never consume
1189      * more than the sum of the bytes remaining in each buffer.  Each
1190      * <code>ByteBuffer</code>'s position is updated to reflect the
1191      * amount of data consumed or produced.  The limits remain the
1192      * same.
1193      * <P>
1194      * The underlying memory used by the <code>srcs</code> and
1195      * <code>dst ByteBuffer</code>s must not be the same.
1196      * <P>
1197      * See the class description for more information on engine closure.
1198      *
1199      * @param   srcs
1200      *          an array of <code>ByteBuffers</code> containing the
1201      *          outbound application data
1202      * @param   offset
1203      *          The offset within the buffer array of the first buffer from
1204      *          which bytes are to be retrieved; it must be non-negative
1205      *          and no larger than <code>srcs.length</code>
1206      * @param   length
1207      *          The maximum number of buffers to be accessed; it must be
1208      *          non-negative and no larger than
1209      *          <code>srcs.length</code>&nbsp;-&nbsp;<code>offset</code>
1210      * @param   dst
1211      *          a <code>ByteBuffer</code> to hold outbound network data
1212      * @return  an <code>SSLEngineResult</code> describing the result
1213      *          of this operation.
1214      * @throws  SSLException
1215      *          A problem was encountered while processing the
1216      *          data that caused the <code>SSLEngine</code> to abort.
1217      *          See the class description for more information on
1218      *          engine closure.
1219      * @throws  IndexOutOfBoundsException
1220      *          if the preconditions on the <code>offset</code> and
1221      *          <code>length</code> parameters do not hold.
1222      * @throws  ReadOnlyBufferException
1223      *          if the <code>dst</code> buffer is read-only.
1224      * @throws  IllegalArgumentException
1225      *          if either <code>srcs</code> or <code>dst</code>
1226      *          is null, or if any element in the <code>srcs</code>
1227      *          subsequence specified is null.
1228      * @throws  IllegalStateException if the client/server mode
1229      *          has not yet been set.
1230      * @see     java.nio.channels.GatheringByteChannel
1231      * @see     java.nio.channels.GatheringByteChannel#write(
1232      *              ByteBuffer[], int, int)
1233      */
wrap(ByteBuffer [] srcs, int offset, int length, ByteBuffer dst)1234     public abstract SSLEngineResult wrap(ByteBuffer [] srcs, int offset,
1235             int length, ByteBuffer dst) throws SSLException;
1236 
1237     /**
1238      * Attempts to decode SSL/TLS network data into a plaintext
1239      * application data buffer.
1240      * <P>
1241      * An invocation of this method behaves in exactly the same manner
1242      * as the invocation:
1243      * <blockquote><pre>
1244      * {@link #unwrap(ByteBuffer, ByteBuffer [], int, int)
1245      *     engine.unwrap(src, new ByteBuffer [] { dst }, 0, 1);}
1246      * </pre</blockquote>
1247      *
1248      * @param   src
1249      *          a <code>ByteBuffer</code> containing inbound network data.
1250      * @param   dst
1251      *          a <code>ByteBuffer</code> to hold inbound application data.
1252      * @return  an <code>SSLEngineResult</code> describing the result
1253      *          of this operation.
1254      * @throws  SSLException
1255      *          A problem was encountered while processing the
1256      *          data that caused the <code>SSLEngine</code> to abort.
1257      *          See the class description for more information on
1258      *          engine closure.
1259      * @throws  ReadOnlyBufferException
1260      *          if the <code>dst</code> buffer is read-only.
1261      * @throws  IllegalArgumentException
1262      *          if either <code>src</code> or <code>dst</code>
1263      *          is null.
1264      * @throws  IllegalStateException if the client/server mode
1265      *          has not yet been set.
1266      * @see     #unwrap(ByteBuffer, ByteBuffer [], int, int)
1267      */
unwrap(ByteBuffer src, ByteBuffer dst)1268     public SSLEngineResult unwrap(ByteBuffer src,
1269             ByteBuffer dst) throws SSLException {
1270         return unwrap(src, new ByteBuffer [] { dst }, 0, 1);
1271     }
1272 
1273     /**
1274      * Attempts to decode SSL/TLS network data into a sequence of plaintext
1275      * application data buffers.
1276      * <P>
1277      * An invocation of this method behaves in exactly the same manner
1278      * as the invocation:
1279      * <blockquote><pre>
1280      * {@link #unwrap(ByteBuffer, ByteBuffer [], int, int)
1281      *     engine.unwrap(src, dsts, 0, dsts.length);}
1282      * </pre</blockquote>
1283      *
1284      * @param   src
1285      *          a <code>ByteBuffer</code> containing inbound network data.
1286      * @param   dsts
1287      *          an array of <code>ByteBuffer</code>s to hold inbound
1288      *          application data.
1289      * @return  an <code>SSLEngineResult</code> describing the result
1290      *          of this operation.
1291      * @throws  SSLException
1292      *          A problem was encountered while processing the
1293      *          data that caused the <code>SSLEngine</code> to abort.
1294      *          See the class description for more information on
1295      *          engine closure.
1296      * @throws  ReadOnlyBufferException
1297      *          if any of the <code>dst</code> buffers are read-only.
1298      * @throws  IllegalArgumentException
1299      *          if either <code>src</code> or <code>dsts</code>
1300      *          is null, or if any element in <code>dsts</code> is null.
1301      * @throws  IllegalStateException if the client/server mode
1302      *          has not yet been set.
1303      * @see     #unwrap(ByteBuffer, ByteBuffer [], int, int)
1304      */
unwrap(ByteBuffer src, ByteBuffer [] dsts)1305     public SSLEngineResult unwrap(ByteBuffer src,
1306             ByteBuffer [] dsts) throws SSLException {
1307         if (dsts == null) {
1308             throw new IllegalArgumentException("dsts == null");
1309         }
1310         return unwrap(src, dsts, 0, dsts.length);
1311     }
1312 
1313     /**
1314      * Attempts to decode SSL/TLS network data into a subsequence of
1315      * plaintext application data buffers.  This <i>"scattering"</i>
1316      * operation decodes, in a single invocation, a sequence of bytes
1317      * into one or more of a given sequence of buffers.  Scattering
1318      * unwraps are often useful when implementing network protocols or
1319      * file formats that, for example, group data into segments
1320      * consisting of one or more fixed-length headers followed by a
1321      * variable-length body.  See
1322      * {@link java.nio.channels.ScatteringByteChannel} for more
1323      * information on scattering, and {@link
1324      * java.nio.channels.ScatteringByteChannel#read(ByteBuffer[],
1325      * int, int)} for more information on the subsequence
1326      * behavior.
1327      * <P>
1328      * Depending on the state of the SSLEngine, this method may consume
1329      * network data without producing any application data (for example,
1330      * it may consume handshake data.)
1331      * <P>
1332      * The application is responsible for reliably obtaining the network
1333      * data from the peer, and for invoking unwrap() on the data in the
1334      * order it was received.  The application must properly synchronize
1335      * multiple calls to this method.
1336      * <P>
1337      * If this <code>SSLEngine</code> has not yet started its initial
1338      * handshake, this method will automatically start the handshake.
1339      * <P>
1340      * This method will attempt to consume one complete SSL/TLS network
1341      * packet, but will never consume more than the sum of the bytes
1342      * remaining in the buffers.  Each <code>ByteBuffer</code>'s
1343      * position is updated to reflect the amount of data consumed or
1344      * produced.  The limits remain the same.
1345      * <P>
1346      * The underlying memory used by the <code>src</code> and
1347      * <code>dsts ByteBuffer</code>s must not be the same.
1348      * <P>
1349      * The inbound network buffer may be modified as a result of this
1350      * call:  therefore if the network data packet is required for some
1351      * secondary purpose, the data should be duplicated before calling this
1352      * method.  Note:  the network data will not be useful to a second
1353      * SSLEngine, as each SSLEngine contains unique random state which
1354      * influences the SSL/TLS messages.
1355      * <P>
1356      * See the class description for more information on engine closure.
1357      *
1358      * @param   src
1359      *          a <code>ByteBuffer</code> containing inbound network data.
1360      * @param   dsts
1361      *          an array of <code>ByteBuffer</code>s to hold inbound
1362      *          application data.
1363      * @param   offset
1364      *          The offset within the buffer array of the first buffer from
1365      *          which bytes are to be transferred; it must be non-negative
1366      *          and no larger than <code>dsts.length</code>.
1367      * @param   length
1368      *          The maximum number of buffers to be accessed; it must be
1369      *          non-negative and no larger than
1370      *          <code>dsts.length</code>&nbsp;-&nbsp;<code>offset</code>.
1371      * @return  an <code>SSLEngineResult</code> describing the result
1372      *          of this operation.
1373      * @throws  SSLException
1374      *          A problem was encountered while processing the
1375      *          data that caused the <code>SSLEngine</code> to abort.
1376      *          See the class description for more information on
1377      *          engine closure.
1378      * @throws  IndexOutOfBoundsException
1379      *          If the preconditions on the <code>offset</code> and
1380      *          <code>length</code> parameters do not hold.
1381      * @throws  ReadOnlyBufferException
1382      *          if any of the <code>dst</code> buffers are read-only.
1383      * @throws  IllegalArgumentException
1384      *          if either <code>src</code> or <code>dsts</code>
1385      *          is null, or if any element in the <code>dsts</code>
1386      *          subsequence specified is null.
1387      * @throws  IllegalStateException if the client/server mode
1388      *          has not yet been set.
1389      * @see     java.nio.channels.ScatteringByteChannel
1390      * @see     java.nio.channels.ScatteringByteChannel#read(
1391      *              ByteBuffer[], int, int)
1392      */
unwrap(ByteBuffer src, ByteBuffer [] dsts, int offset, int length)1393     public abstract SSLEngineResult unwrap(ByteBuffer src,
1394             ByteBuffer [] dsts, int offset, int length) throws SSLException;
1395 
1396 
1397     /**
1398      * Returns a delegated <code>Runnable</code> task for
1399      * this <code>SSLEngine</code>.
1400      * <P>
1401      * <code>SSLEngine</code> operations may require the results of
1402      * operations that block, or may take an extended period of time to
1403      * complete.  This method is used to obtain an outstanding {@link
1404      * java.lang.Runnable} operation (task).  Each task must be assigned
1405      * a thread (possibly the current) to perform the {@link
1406      * java.lang.Runnable#run() run} operation.  Once the
1407      * <code>run</code> method returns, the <code>Runnable</code> object
1408      * is no longer needed and may be discarded.
1409      * <P>
1410      * Delegated tasks run in the <code>AccessControlContext</code>
1411      * in place when this object was created.
1412      * <P>
1413      * A call to this method will return each outstanding task
1414      * exactly once.
1415      * <P>
1416      * Multiple delegated tasks can be run in parallel.
1417      *
1418      * @return  a delegated <code>Runnable</code> task, or null
1419      *          if none are available.
1420      */
getDelegatedTask()1421     public abstract Runnable getDelegatedTask();
1422 
1423 
1424     /**
1425      * Signals that no more inbound network data will be sent
1426      * to this <code>SSLEngine</code>.
1427      * <P>
1428      * If the application initiated the closing process by calling
1429      * {@link #closeOutbound()}, under some circumstances it is not
1430      * required that the initiator wait for the peer's corresponding
1431      * close message.  (See section 7.2.1 of the TLS specification (<A
1432      * HREF="http://www.ietf.org/rfc/rfc2246.txt">RFC 2246</A>) for more
1433      * information on waiting for closure alerts.)  In such cases, this
1434      * method need not be called.
1435      * <P>
1436      * But if the application did not initiate the closure process, or
1437      * if the circumstances above do not apply, this method should be
1438      * called whenever the end of the SSL/TLS data stream is reached.
1439      * This ensures closure of the inbound side, and checks that the
1440      * peer followed the SSL/TLS close procedure properly, thus
1441      * detecting possible truncation attacks.
1442      * <P>
1443      * This method is idempotent:  if the inbound side has already
1444      * been closed, this method does not do anything.
1445      * <P>
1446      * {@link #wrap(ByteBuffer, ByteBuffer) wrap()} should be
1447      * called to flush any remaining handshake data.
1448      *
1449      * @throws  SSLException
1450      *          if this engine has not received the proper SSL/TLS close
1451      *          notification message from the peer.
1452      *
1453      * @see     #isInboundDone()
1454      * @see     #isOutboundDone()
1455      */
closeInbound()1456     public abstract void closeInbound() throws SSLException;
1457 
1458 
1459     /**
1460      * Returns whether {@link #unwrap(ByteBuffer, ByteBuffer)} will
1461      * accept any more inbound data messages.
1462      *
1463      * @return  true if the <code>SSLEngine</code> will not
1464      *          consume anymore network data (and by implication,
1465      *          will not produce any more application data.)
1466      * @see     #closeInbound()
1467      */
isInboundDone()1468     public abstract boolean isInboundDone();
1469 
1470 
1471     /**
1472      * Signals that no more outbound application data will be sent
1473      * on this <code>SSLEngine</code>.
1474      * <P>
1475      * This method is idempotent:  if the outbound side has already
1476      * been closed, this method does not do anything.
1477      * <P>
1478      * {@link #wrap(ByteBuffer, ByteBuffer)} should be
1479      * called to flush any remaining handshake data.
1480      *
1481      * @see     #isOutboundDone()
1482      */
closeOutbound()1483     public abstract void closeOutbound();
1484 
1485 
1486     /**
1487      * Returns whether {@link #wrap(ByteBuffer, ByteBuffer)} will
1488      * produce any more outbound data messages.
1489      * <P>
1490      * Note that during the closure phase, a <code>SSLEngine</code> may
1491      * generate handshake closure data that must be sent to the peer.
1492      * <code>wrap()</code> must be called to generate this data.  When
1493      * this method returns true, no more outbound data will be created.
1494      *
1495      * @return  true if the <code>SSLEngine</code> will not produce
1496      *          any more network data
1497      *
1498      * @see     #closeOutbound()
1499      * @see     #closeInbound()
1500      */
isOutboundDone()1501     public abstract boolean isOutboundDone();
1502 
1503 
1504     /**
1505      * Returns the names of the cipher suites which could be enabled for use
1506      * on this engine.  Normally, only a subset of these will actually
1507      * be enabled by default, since this list may include cipher suites which
1508      * do not meet quality of service requirements for those defaults.  Such
1509      * cipher suites might be useful in specialized applications.
1510      *
1511      * @return  an array of cipher suite names
1512      * @see     #getEnabledCipherSuites()
1513      * @see     #setEnabledCipherSuites(String [])
1514      */
getSupportedCipherSuites()1515     public abstract String [] getSupportedCipherSuites();
1516 
1517 
1518     /**
1519      * Returns the names of the SSL cipher suites which are currently
1520      * enabled for use on this engine.  When an SSLEngine is first
1521      * created, all enabled cipher suites support a minimum quality of
1522      * service.  Thus, in some environments this value might be empty.
1523      * <P>
1524      * Even if a suite has been enabled, it might never be used.  (For
1525      * example, the peer does not support it, the requisite
1526      * certificates/private keys for the suite are not available, or an
1527      * anonymous suite is enabled but authentication is required.)
1528      *
1529      * @return  an array of cipher suite names
1530      * @see     #getSupportedCipherSuites()
1531      * @see     #setEnabledCipherSuites(String [])
1532      */
getEnabledCipherSuites()1533     public abstract String [] getEnabledCipherSuites();
1534 
1535 
1536     /**
1537      * Sets the cipher suites enabled for use on this engine.
1538      * <P>
1539      * Each cipher suite in the <code>suites</code> parameter must have
1540      * been listed by getSupportedCipherSuites(), or the method will
1541      * fail.  Following a successful call to this method, only suites
1542      * listed in the <code>suites</code> parameter are enabled for use.
1543      * <P>
1544      * See {@link #getEnabledCipherSuites()} for more information
1545      * on why a specific cipher suite may never be used on a engine.
1546      *
1547      * @param   suites Names of all the cipher suites to enable
1548      * @throws  IllegalArgumentException when one or more of the ciphers
1549      *          named by the parameter is not supported, or when the
1550      *          parameter is null.
1551      * @see     #getSupportedCipherSuites()
1552      * @see     #getEnabledCipherSuites()
1553      */
setEnabledCipherSuites(String suites [])1554     public abstract void setEnabledCipherSuites(String suites []);
1555 
1556 
1557     /**
1558      * Returns the names of the protocols which could be enabled for use
1559      * with this <code>SSLEngine</code>.
1560      *
1561      * @return  an array of protocols supported
1562      */
getSupportedProtocols()1563     public abstract String [] getSupportedProtocols();
1564 
1565 
1566     /**
1567      * Returns the names of the protocol versions which are currently
1568      * enabled for use with this <code>SSLEngine</code>.
1569      *
1570      * @return  an array of protocols
1571      * @see     #setEnabledProtocols(String [])
1572      */
getEnabledProtocols()1573     public abstract String [] getEnabledProtocols();
1574 
1575 
1576     /**
1577      * Set the protocol versions enabled for use on this engine.
1578      * <P>
1579      * The protocols must have been listed by getSupportedProtocols()
1580      * as being supported.  Following a successful call to this method,
1581      * only protocols listed in the <code>protocols</code> parameter
1582      * are enabled for use.
1583      *
1584      * @param   protocols Names of all the protocols to enable.
1585      * @throws  IllegalArgumentException when one or more of
1586      *          the protocols named by the parameter is not supported or
1587      *          when the protocols parameter is null.
1588      * @see     #getEnabledProtocols()
1589      */
setEnabledProtocols(String protocols[])1590     public abstract void setEnabledProtocols(String protocols[]);
1591 
1592 
1593     /**
1594      * Returns the <code>SSLSession</code> in use in this
1595      * <code>SSLEngine</code>.
1596      * <P>
1597      * These can be long lived, and frequently correspond to an entire
1598      * login session for some user.  The session specifies a particular
1599      * cipher suite which is being actively used by all connections in
1600      * that session, as well as the identities of the session's client
1601      * and server.
1602      * <P>
1603      * Unlike {@link SSLSocket#getSession()}
1604      * this method does not block until handshaking is complete.
1605      * <P>
1606      * Until the initial handshake has completed, this method returns
1607      * a session object which reports an invalid cipher suite of
1608      * "SSL_NULL_WITH_NULL_NULL".
1609      *
1610      * @return  the <code>SSLSession</code> for this <code>SSLEngine</code>
1611      * @see     SSLSession
1612      */
getSession()1613     public abstract SSLSession getSession();
1614 
1615 
1616     /**
1617      * Returns the {@code SSLSession} being constructed during a SSL/TLS
1618      * handshake.
1619      * <p>
1620      * TLS protocols may negotiate parameters that are needed when using
1621      * an instance of this class, but before the {@code SSLSession} has
1622      * been completely initialized and made available via {@code getSession}.
1623      * For example, the list of valid signature algorithms may restrict
1624      * the type of certificates that can used during TrustManager
1625      * decisions, or the maximum TLS fragment packet sizes can be
1626      * resized to better support the network environment.
1627      * <p>
1628      * This method provides early access to the {@code SSLSession} being
1629      * constructed.  Depending on how far the handshake has progressed,
1630      * some data may not yet be available for use.  For example, if a
1631      * remote server will be sending a Certificate chain, but that chain
1632      * has yet not been processed, the {@code getPeerCertificates}
1633      * method of {@code SSLSession} will throw a
1634      * SSLPeerUnverifiedException.  Once that chain has been processed,
1635      * {@code getPeerCertificates} will return the proper value.
1636      *
1637      * @see SSLSocket
1638      * @see SSLSession
1639      * @see ExtendedSSLSession
1640      * @see X509ExtendedKeyManager
1641      * @see X509ExtendedTrustManager
1642      *
1643      * @return null if this instance is not currently handshaking, or
1644      *         if the current handshake has not progressed far enough to
1645      *         create a basic SSLSession.  Otherwise, this method returns the
1646      *         {@code SSLSession} currently being negotiated.
1647      * @throws UnsupportedOperationException if the underlying provider
1648      *         does not implement the operation.
1649      *
1650      * @since 1.7
1651      */
getHandshakeSession()1652     public SSLSession getHandshakeSession() {
1653         throw new UnsupportedOperationException();
1654     }
1655 
1656 
1657     /**
1658      * Initiates handshaking (initial or renegotiation) on this SSLEngine.
1659      * <P>
1660      * This method is not needed for the initial handshake, as the
1661      * <code>wrap()</code> and <code>unwrap()</code> methods will
1662      * implicitly call this method if handshaking has not already begun.
1663      * <P>
1664      * Note that the peer may also request a session renegotiation with
1665      * this <code>SSLEngine</code> by sending the appropriate
1666      * session renegotiate handshake message.
1667      * <P>
1668      * Unlike the {@link SSLSocket#startHandshake()
1669      * SSLSocket#startHandshake()} method, this method does not block
1670      * until handshaking is completed.
1671      * <P>
1672      * To force a complete SSL/TLS session renegotiation, the current
1673      * session should be invalidated prior to calling this method.
1674      * <P>
1675      * Some protocols may not support multiple handshakes on an existing
1676      * engine and may throw an <code>SSLException</code>.
1677      *
1678      * @throws  SSLException
1679      *          if a problem was encountered while signaling the
1680      *          <code>SSLEngine</code> to begin a new handshake.
1681      *          See the class description for more information on
1682      *          engine closure.
1683      * @throws  IllegalStateException if the client/server mode
1684      *          has not yet been set.
1685      * @see     SSLSession#invalidate()
1686      */
beginHandshake()1687     public abstract void beginHandshake() throws SSLException;
1688 
1689 
1690     /**
1691      * Returns the current handshake status for this <code>SSLEngine</code>.
1692      *
1693      * @return  the current <code>SSLEngineResult.HandshakeStatus</code>.
1694      */
getHandshakeStatus()1695     public abstract SSLEngineResult.HandshakeStatus getHandshakeStatus();
1696 
1697 
1698     /**
1699      * Configures the engine to use client (or server) mode when
1700      * handshaking.
1701      * <P>
1702      * This method must be called before any handshaking occurs.
1703      * Once handshaking has begun, the mode can not be reset for the
1704      * life of this engine.
1705      * <P>
1706      * Servers normally authenticate themselves, and clients
1707      * are not required to do so.
1708      *
1709      * @param   mode true if the engine should start its handshaking
1710      *          in "client" mode
1711      * @throws  IllegalArgumentException if a mode change is attempted
1712      *          after the initial handshake has begun.
1713      * @see     #getUseClientMode()
1714      */
setUseClientMode(boolean mode)1715     public abstract void setUseClientMode(boolean mode);
1716 
1717 
1718     /**
1719      * Returns true if the engine is set to use client mode when
1720      * handshaking.
1721      *
1722      * @return  true if the engine should do handshaking
1723      *          in "client" mode
1724      * @see     #setUseClientMode(boolean)
1725      */
getUseClientMode()1726     public abstract boolean getUseClientMode();
1727 
1728 
1729     /**
1730      * Configures the engine to <i>require</i> client authentication.  This
1731      * option is only useful for engines in the server mode.
1732      * <P>
1733      * An engine's client authentication setting is one of the following:
1734      * <ul>
1735      * <li> client authentication required
1736      * <li> client authentication requested
1737      * <li> no client authentication desired
1738      * </ul>
1739      * <P>
1740      * Unlike {@link #setWantClientAuth(boolean)}, if this option is set and
1741      * the client chooses not to provide authentication information
1742      * about itself, <i>the negotiations will stop and the engine will
1743      * begin its closure procedure</i>.
1744      * <P>
1745      * Calling this method overrides any previous setting made by
1746      * this method or {@link #setWantClientAuth(boolean)}.
1747      *
1748      * @param   need set to true if client authentication is required,
1749      *          or false if no client authentication is desired.
1750      * @see     #getNeedClientAuth()
1751      * @see     #setWantClientAuth(boolean)
1752      * @see     #getWantClientAuth()
1753      * @see     #setUseClientMode(boolean)
1754      */
setNeedClientAuth(boolean need)1755     public abstract void setNeedClientAuth(boolean need);
1756 
1757 
1758     /**
1759      * Returns true if the engine will <i>require</i> client authentication.
1760      * This option is only useful to engines in the server mode.
1761      *
1762      * @return  true if client authentication is required,
1763      *          or false if no client authentication is desired.
1764      * @see     #setNeedClientAuth(boolean)
1765      * @see     #setWantClientAuth(boolean)
1766      * @see     #getWantClientAuth()
1767      * @see     #setUseClientMode(boolean)
1768      */
getNeedClientAuth()1769     public abstract boolean getNeedClientAuth();
1770 
1771 
1772     /**
1773      * Configures the engine to <i>request</i> client authentication.
1774      * This option is only useful for engines in the server mode.
1775      * <P>
1776      * An engine's client authentication setting is one of the following:
1777      * <ul>
1778      * <li> client authentication required
1779      * <li> client authentication requested
1780      * <li> no client authentication desired
1781      * </ul>
1782      * <P>
1783      * Unlike {@link #setNeedClientAuth(boolean)}, if this option is set and
1784      * the client chooses not to provide authentication information
1785      * about itself, <i>the negotiations will continue</i>.
1786      * <P>
1787      * Calling this method overrides any previous setting made by
1788      * this method or {@link #setNeedClientAuth(boolean)}.
1789      *
1790      * @param   want set to true if client authentication is requested,
1791      *          or false if no client authentication is desired.
1792      * @see     #getWantClientAuth()
1793      * @see     #setNeedClientAuth(boolean)
1794      * @see     #getNeedClientAuth()
1795      * @see     #setUseClientMode(boolean)
1796      */
setWantClientAuth(boolean want)1797     public abstract void setWantClientAuth(boolean want);
1798 
1799 
1800     /**
1801      * Returns true if the engine will <i>request</i> client authentication.
1802      * This option is only useful for engines in the server mode.
1803      *
1804      * @return  true if client authentication is requested,
1805      *          or false if no client authentication is desired.
1806      * @see     #setNeedClientAuth(boolean)
1807      * @see     #getNeedClientAuth()
1808      * @see     #setWantClientAuth(boolean)
1809      * @see     #setUseClientMode(boolean)
1810      */
getWantClientAuth()1811     public abstract boolean getWantClientAuth();
1812 
1813 
1814     /**
1815      * Controls whether new SSL sessions may be established by this engine.
1816      * If session creations are not allowed, and there are no
1817      * existing sessions to resume, there will be no successful
1818      * handshaking.
1819      *
1820      * @param   flag true indicates that sessions may be created; this
1821      *          is the default.  false indicates that an existing session
1822      *          must be resumed
1823      * @see     #getEnableSessionCreation()
1824      */
setEnableSessionCreation(boolean flag)1825     public abstract void setEnableSessionCreation(boolean flag);
1826 
1827 
1828     /**
1829      * Returns true if new SSL sessions may be established by this engine.
1830      *
1831      * @return  true indicates that sessions may be created; this
1832      *          is the default.  false indicates that an existing session
1833      *          must be resumed
1834      * @see     #setEnableSessionCreation(boolean)
1835      */
getEnableSessionCreation()1836     public abstract boolean getEnableSessionCreation();
1837 
1838     /**
1839      * Returns the SSLParameters in effect for this SSLEngine.
1840      * The ciphersuites and protocols of the returned SSLParameters
1841      * are always non-null.
1842      *
1843      * @return the SSLParameters in effect for this SSLEngine.
1844      * @since 1.6
1845      */
getSSLParameters()1846     public SSLParameters getSSLParameters() {
1847         SSLParameters params = new SSLParameters();
1848         params.setCipherSuites(getEnabledCipherSuites());
1849         params.setProtocols(getEnabledProtocols());
1850         if (getNeedClientAuth()) {
1851             params.setNeedClientAuth(true);
1852         } else if (getWantClientAuth()) {
1853             params.setWantClientAuth(true);
1854         }
1855         return params;
1856     }
1857 
1858     /**
1859      * Applies SSLParameters to this engine.
1860      *
1861      * <p>This means:
1862      * <ul>
1863      * <li>if <code>params.getCipherSuites()</code> is non-null,
1864      *   <code>setEnabledCipherSuites()</code> is called with that value
1865      * <li>if <code>params.getProtocols()</code> is non-null,
1866      *   <code>setEnabledProtocols()</code> is called with that value
1867      * <li>if <code>params.getNeedClientAuth()</code> or
1868      *   <code>params.getWantClientAuth()</code> return <code>true</code>,
1869      *   <code>setNeedClientAuth(true)</code> and
1870      *   <code>setWantClientAuth(true)</code> are called, respectively;
1871      *   otherwise <code>setWantClientAuth(false)</code> is called.
1872      * </ul>
1873      *
1874      * @param params the parameters
1875      * @throws IllegalArgumentException if the setEnabledCipherSuites() or
1876      *    the setEnabledProtocols() call fails
1877      * @since 1.6
1878      */
setSSLParameters(SSLParameters params)1879     public void setSSLParameters(SSLParameters params) {
1880         String[] s;
1881         s = params.getCipherSuites();
1882         if (s != null) {
1883             setEnabledCipherSuites(s);
1884         }
1885         s = params.getProtocols();
1886         if (s != null) {
1887             setEnabledProtocols(s);
1888         }
1889         if (params.getNeedClientAuth()) {
1890             setNeedClientAuth(true);
1891         } else if (params.getWantClientAuth()) {
1892             setWantClientAuth(true);
1893         } else {
1894             setWantClientAuth(false);
1895         }
1896     }
1897 
1898 }
1899