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1 /*
2  * Copyright (c) 2003, 2013, 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
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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>{@code
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  * <HR>
333  *
334  * <B>Concurrency Notes</B>:
335  * There are two concurrency issues to be aware of:
336  *
337  * <OL>
338  *      <li>The <code>wrap()</code> and <code>unwrap()</code> methods
339  *      may execute concurrently of each other.
340  *
341  *      <li> The SSL/TLS protocols employ ordered packets.
342  *      Applications must take care to ensure that generated packets
343  *      are delivered in sequence.  If packets arrive
344  *      out-of-order, unexpected or fatal results may occur.
345  * <P>
346  *      For example:
347  *
348  *      <pre>
349  *              synchronized (outboundLock) {
350  *                  sslEngine.wrap(src, dst);
351  *                  outboundQueue.put(dst);
352  *              }
353  *      </pre>
354  *
355  *      As a corollary, two threads must not attempt to call the same method
356  *      (either <code>wrap()</code> or <code>unwrap()</code>) concurrently,
357  *      because there is no way to guarantee the eventual packet ordering.
358  * </OL>
359  *
360  * <h3>Default configuration for different Android versions</h3>
361  * <p>{@code SSLEngine} instances obtained from default {@link SSLContext} are configured as
362  * follows:
363  *
364  * <style type="text/css">
365  *   tr.deprecated {
366  *     background-color: #ccc;
367  *     color: #999;
368  *     font-style: italic;
369  *   }
370  * </style>
371  *
372  * <h4>Protocols</h4>
373  * <table>
374  *     <thead>
375  *         <tr>
376  *             <th>Protocol</th>
377  *             <th>Supported (API Levels)</th>
378  *             <th>Enabled by default (API Levels)</th>
379  *         </tr>
380  *     </thead>
381  *     <tbody>
382  *         <tr class="deprecated">
383  *             <td>SSLv3</td>
384  *             <td>1&ndash;25</td>
385  *             <td>1&ndash;22</td>
386  *         </tr>
387  *         <tr>
388  *             <td>TLSv1</td>
389  *             <td>1+</td>
390  *             <td>1+</td>
391  *         </tr>
392  *         <tr>
393  *             <td>TLSv1.1</td>
394  *             <td>20+</td>
395  *             <td>20+</td>
396  *         </tr>
397  *         <tr>
398  *             <td>TLSv1.2</td>
399  *             <td>20+</td>
400  *             <td>20+</td>
401  *         </tr>
402  *     </tbody>
403  * </table>
404  *
405  * <h4>Cipher suites</h4>
406  * <table>
407  *   <thead>
408  *     <tr>
409  *       <th>Cipher suite</th>
410  *       <th>Supported (API Levels)</th>
411  *       <th>Enabled by default (API Levels)</th>
412  *     </tr>
413  *   </thead>
414  *   <tbody>
415  *     <tr class="deprecated">
416  *       <td>SSL_DHE_DSS_EXPORT_WITH_DES40_CBC_SHA</td>
417  *       <td>9-22</td>
418  *       <td>9-19</td>
419  *     </tr>
420  *     <tr class="deprecated">
421  *       <td>SSL_DHE_DSS_WITH_3DES_EDE_CBC_SHA</td>
422  *       <td>9-22</td>
423  *       <td>9-19</td>
424  *     </tr>
425  *     <tr class="deprecated">
426  *       <td>SSL_DHE_DSS_WITH_DES_CBC_SHA</td>
427  *       <td>9-22</td>
428  *       <td>9-19</td>
429  *     </tr>
430  *     <tr class="deprecated">
431  *       <td>SSL_DHE_RSA_EXPORT_WITH_DES40_CBC_SHA</td>
432  *       <td>9-22</td>
433  *       <td>9-19</td>
434  *     </tr>
435  *     <tr class="deprecated">
436  *       <td>SSL_DHE_RSA_WITH_3DES_EDE_CBC_SHA</td>
437  *       <td>9-22</td>
438  *       <td>9-19</td>
439  *     </tr>
440  *     <tr class="deprecated">
441  *       <td>SSL_DHE_RSA_WITH_DES_CBC_SHA</td>
442  *       <td>9-22</td>
443  *       <td>9-19</td>
444  *     </tr>
445  *     <tr class="deprecated">
446  *       <td>SSL_DH_anon_EXPORT_WITH_DES40_CBC_SHA</td>
447  *       <td>9-22</td>
448  *       <td></td>
449  *     </tr>
450  *     <tr class="deprecated">
451  *       <td>SSL_DH_anon_EXPORT_WITH_RC4_40_MD5</td>
452  *       <td>9-22</td>
453  *       <td></td>
454  *     </tr>
455  *     <tr class="deprecated">
456  *       <td>SSL_DH_anon_WITH_3DES_EDE_CBC_SHA</td>
457  *       <td>9-22</td>
458  *       <td></td>
459  *     </tr>
460  *     <tr class="deprecated">
461  *       <td>SSL_DH_anon_WITH_DES_CBC_SHA</td>
462  *       <td>9-22</td>
463  *       <td></td>
464  *     </tr>
465  *     <tr class="deprecated">
466  *       <td>SSL_DH_anon_WITH_RC4_128_MD5</td>
467  *       <td>9-22</td>
468  *       <td></td>
469  *     </tr>
470  *     <tr class="deprecated">
471  *       <td>SSL_RSA_EXPORT_WITH_DES40_CBC_SHA</td>
472  *       <td>9-22</td>
473  *       <td>9-19</td>
474  *     </tr>
475  *     <tr class="deprecated">
476  *       <td>SSL_RSA_EXPORT_WITH_RC4_40_MD5</td>
477  *       <td>9-22</td>
478  *       <td>9-19</td>
479  *     </tr>
480  *     <tr>
481  *       <td>SSL_RSA_WITH_3DES_EDE_CBC_SHA</td>
482  *       <td>9+</td>
483  *       <td>9-19</td>
484  *     </tr>
485  *     <tr class="deprecated">
486  *       <td>SSL_RSA_WITH_DES_CBC_SHA</td>
487  *       <td>9-22</td>
488  *       <td>9-19</td>
489  *     </tr>
490  *     <tr class="deprecated">
491  *       <td>SSL_RSA_WITH_NULL_MD5</td>
492  *       <td>9-22</td>
493  *       <td></td>
494  *     </tr>
495  *     <tr class="deprecated">
496  *       <td>SSL_RSA_WITH_NULL_SHA</td>
497  *       <td>9-22</td>
498  *       <td></td>
499  *     </tr>
500  *     <tr class="deprecated">
501  *       <td>SSL_RSA_WITH_RC4_128_MD5</td>
502  *       <td>9-25</td>
503  *       <td>9-19</td>
504  *     </tr>
505  *     <tr class="deprecated">
506  *       <td>SSL_RSA_WITH_RC4_128_SHA</td>
507  *       <td>9-25</td>
508  *       <td>9-23</td>
509  *     </tr>
510  *     <tr class="deprecated">
511  *       <td>TLS_DHE_DSS_EXPORT_WITH_DES40_CBC_SHA</td>
512  *       <td>1-8</td>
513  *       <td>1-8</td>
514  *     </tr>
515  *     <tr class="deprecated">
516  *       <td>TLS_DHE_DSS_WITH_3DES_EDE_CBC_SHA</td>
517  *       <td>1-8</td>
518  *       <td>1-8</td>
519  *     </tr>
520  *     <tr class="deprecated">
521  *       <td>TLS_DHE_DSS_WITH_AES_128_CBC_SHA</td>
522  *       <td>9-22</td>
523  *       <td>9-22</td>
524  *     </tr>
525  *     <tr class="deprecated">
526  *       <td>TLS_DHE_DSS_WITH_AES_128_CBC_SHA256</td>
527  *       <td>20-22</td>
528  *       <td></td>
529  *     </tr>
530  *     <tr class="deprecated">
531  *       <td>TLS_DHE_DSS_WITH_AES_128_GCM_SHA256</td>
532  *       <td>20-22</td>
533  *       <td></td>
534  *     </tr>
535  *     <tr class="deprecated">
536  *       <td>TLS_DHE_DSS_WITH_AES_256_CBC_SHA</td>
537  *       <td>9-22</td>
538  *       <td>20-22</td>
539  *     </tr>
540  *     <tr class="deprecated">
541  *       <td>TLS_DHE_DSS_WITH_AES_256_CBC_SHA256</td>
542  *       <td>20-22</td>
543  *       <td></td>
544  *     </tr>
545  *     <tr class="deprecated">
546  *       <td>TLS_DHE_DSS_WITH_AES_256_GCM_SHA384</td>
547  *       <td>20-22</td>
548  *       <td></td>
549  *     </tr>
550  *     <tr class="deprecated">
551  *       <td>TLS_DHE_DSS_WITH_DES_CBC_SHA</td>
552  *       <td>1-8</td>
553  *       <td>1-8</td>
554  *     </tr>
555  *     <tr class="deprecated">
556  *       <td>TLS_DHE_RSA_EXPORT_WITH_DES40_CBC_SHA</td>
557  *       <td>1-8</td>
558  *       <td>1-8</td>
559  *     </tr>
560  *     <tr class="deprecated">
561  *       <td>TLS_DHE_RSA_WITH_3DES_EDE_CBC_SHA</td>
562  *       <td>1-8</td>
563  *       <td>1-8</td>
564  *     </tr>
565  *     <tr class="deprecated">
566  *       <td>TLS_DHE_RSA_WITH_AES_128_CBC_SHA</td>
567  *       <td>9-25</td>
568  *       <td>9-25</td>
569  *     </tr>
570  *     <tr class="deprecated">
571  *       <td>TLS_DHE_RSA_WITH_AES_128_CBC_SHA256</td>
572  *       <td>20-25</td>
573  *       <td></td>
574  *     </tr>
575  *     <tr class="deprecated">
576  *       <td>TLS_DHE_RSA_WITH_AES_128_GCM_SHA256</td>
577  *       <td>20-25</td>
578  *       <td>20-25</td>
579  *     </tr>
580  *     <tr class="deprecated">
581  *       <td>TLS_DHE_RSA_WITH_AES_256_CBC_SHA</td>
582  *       <td>9-25</td>
583  *       <td>20-25</td>
584  *     </tr>
585  *     <tr class="deprecated">
586  *       <td>TLS_DHE_RSA_WITH_AES_256_CBC_SHA256</td>
587  *       <td>20-25</td>
588  *       <td></td>
589  *     </tr>
590  *     <tr class="deprecated">
591  *       <td>TLS_DHE_RSA_WITH_AES_256_GCM_SHA384</td>
592  *       <td>20-25</td>
593  *       <td>20-25</td>
594  *     </tr>
595  *     <tr class="deprecated">
596  *       <td>TLS_DHE_RSA_WITH_DES_CBC_SHA</td>
597  *       <td>1-8</td>
598  *       <td>1-8</td>
599  *     </tr>
600  *     <tr class="deprecated">
601  *       <td>TLS_DH_DSS_EXPORT_WITH_DES40_CBC_SHA</td>
602  *       <td>1-8</td>
603  *       <td></td>
604  *     </tr>
605  *     <tr class="deprecated">
606  *       <td>TLS_DH_DSS_WITH_3DES_EDE_CBC_SHA</td>
607  *       <td>1-8</td>
608  *       <td></td>
609  *     </tr>
610  *     <tr class="deprecated">
611  *       <td>TLS_DH_DSS_WITH_DES_CBC_SHA</td>
612  *       <td>1-8</td>
613  *       <td></td>
614  *     </tr>
615  *     <tr class="deprecated">
616  *       <td>TLS_DH_RSA_EXPORT_WITH_DES40_CBC_SHA</td>
617  *       <td>1-8</td>
618  *       <td></td>
619  *     </tr>
620  *     <tr class="deprecated">
621  *       <td>TLS_DH_RSA_WITH_3DES_EDE_CBC_SHA</td>
622  *       <td>1-8</td>
623  *       <td></td>
624  *     </tr>
625  *     <tr class="deprecated">
626  *       <td>TLS_DH_RSA_WITH_DES_CBC_SHA</td>
627  *       <td>1-8</td>
628  *       <td></td>
629  *     </tr>
630  *     <tr class="deprecated">
631  *       <td>TLS_DH_anon_EXPORT_WITH_DES40_CBC_SHA</td>
632  *       <td>1-8</td>
633  *       <td></td>
634  *     </tr>
635  *     <tr class="deprecated">
636  *       <td>TLS_DH_anon_WITH_3DES_EDE_CBC_SHA</td>
637  *       <td>1-8</td>
638  *       <td></td>
639  *     </tr>
640  *     <tr class="deprecated">
641  *       <td>TLS_DH_anon_WITH_AES_128_CBC_SHA</td>
642  *       <td>9-22</td>
643  *       <td></td>
644  *     </tr>
645  *     <tr class="deprecated">
646  *       <td>TLS_DH_anon_WITH_AES_128_CBC_SHA256</td>
647  *       <td>20-22</td>
648  *       <td></td>
649  *     </tr>
650  *     <tr class="deprecated">
651  *       <td>TLS_DH_anon_WITH_AES_128_GCM_SHA256</td>
652  *       <td>20-22</td>
653  *       <td></td>
654  *     </tr>
655  *     <tr class="deprecated">
656  *       <td>TLS_DH_anon_WITH_AES_256_CBC_SHA</td>
657  *       <td>9-22</td>
658  *       <td></td>
659  *     </tr>
660  *     <tr class="deprecated">
661  *       <td>TLS_DH_anon_WITH_AES_256_CBC_SHA256</td>
662  *       <td>20-22</td>
663  *       <td></td>
664  *     </tr>
665  *     <tr class="deprecated">
666  *       <td>TLS_DH_anon_WITH_AES_256_GCM_SHA384</td>
667  *       <td>20-22</td>
668  *       <td></td>
669  *     </tr>
670  *     <tr class="deprecated">
671  *       <td>TLS_DH_anon_WITH_DES_CBC_SHA</td>
672  *       <td>1-8</td>
673  *       <td></td>
674  *     </tr>
675  *     <tr class="deprecated">
676  *       <td>TLS_ECDHE_ECDSA_WITH_3DES_EDE_CBC_SHA</td>
677  *       <td>20-22</td>
678  *       <td></td>
679  *     </tr>
680  *     <tr>
681  *       <td>TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA</td>
682  *       <td>20+</td>
683  *       <td>20+</td>
684  *     </tr>
685  *     <tr>
686  *       <td>TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256</td>
687  *       <td>20+</td>
688  *       <td></td>
689  *     </tr>
690  *     <tr>
691  *       <td>TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256</td>
692  *       <td>20+</td>
693  *       <td>20+</td>
694  *     </tr>
695  *     <tr>
696  *       <td>TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA</td>
697  *       <td>20+</td>
698  *       <td>20+</td>
699  *     </tr>
700  *     <tr>
701  *       <td>TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384</td>
702  *       <td>20+</td>
703  *       <td></td>
704  *     </tr>
705  *     <tr>
706  *       <td>TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384</td>
707  *       <td>20+</td>
708  *       <td>20+</td>
709  *     </tr>
710  *     <tr>
711  *       <td>TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256</td>
712  *       <td>24+</td>
713  *       <td>24+</td>
714  *     </tr>
715  *     <tr class="deprecated">
716  *       <td>TLS_ECDHE_ECDSA_WITH_NULL_SHA</td>
717  *       <td>20-22</td>
718  *       <td></td>
719  *     </tr>
720  *     <tr class="deprecated">
721  *       <td>TLS_ECDHE_ECDSA_WITH_RC4_128_SHA</td>
722  *       <td>20-25</td>
723  *       <td>20-23</td>
724  *     </tr>
725  *     <tr>
726  *       <td>TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA</td>
727  *       <td>21+</td>
728  *       <td>21+</td>
729  *     </tr>
730  *     <tr>
731  *       <td>TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA</td>
732  *       <td>21+</td>
733  *       <td>21+</td>
734  *     </tr>
735  *     <tr>
736  *       <td>TLS_ECDHE_PSK_WITH_CHACHA20_POLY1305_SHA256</td>
737  *       <td>24+</td>
738  *       <td>24+</td>
739  *     </tr>
740  *     <tr class="deprecated">
741  *       <td>TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA</td>
742  *       <td>20-22</td>
743  *       <td></td>
744  *     </tr>
745  *     <tr>
746  *       <td>TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA</td>
747  *       <td>20+</td>
748  *       <td>20+</td>
749  *     </tr>
750  *     <tr>
751  *       <td>TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256</td>
752  *       <td>20+</td>
753  *       <td></td>
754  *     </tr>
755  *     <tr>
756  *       <td>TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256</td>
757  *       <td>20+</td>
758  *       <td>20+</td>
759  *     </tr>
760  *     <tr>
761  *       <td>TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA</td>
762  *       <td>20+</td>
763  *       <td>20+</td>
764  *     </tr>
765  *     <tr>
766  *       <td>TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384</td>
767  *       <td>20+</td>
768  *       <td></td>
769  *     </tr>
770  *     <tr>
771  *       <td>TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384</td>
772  *       <td>20+</td>
773  *       <td>20+</td>
774  *     </tr>
775  *     <tr>
776  *       <td>TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256</td>
777  *       <td>24+</td>
778  *       <td>24+</td>
779  *     </tr>
780  *     <tr class="deprecated">
781  *       <td>TLS_ECDHE_RSA_WITH_NULL_SHA</td>
782  *       <td>20-22</td>
783  *       <td></td>
784  *     </tr>
785  *     <tr class="deprecated">
786  *       <td>TLS_ECDHE_RSA_WITH_RC4_128_SHA</td>
787  *       <td>20-25</td>
788  *       <td>20-23</td>
789  *     </tr>
790  *     <tr class="deprecated">
791  *       <td>TLS_ECDH_ECDSA_WITH_3DES_EDE_CBC_SHA</td>
792  *       <td>20-22</td>
793  *       <td></td>
794  *     </tr>
795  *     <tr class="deprecated">
796  *       <td>TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA</td>
797  *       <td>20-22</td>
798  *       <td></td>
799  *     </tr>
800  *     <tr class="deprecated">
801  *       <td>TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA256</td>
802  *       <td>20-22</td>
803  *       <td></td>
804  *     </tr>
805  *     <tr class="deprecated">
806  *       <td>TLS_ECDH_ECDSA_WITH_AES_128_GCM_SHA256</td>
807  *       <td>20-22</td>
808  *       <td></td>
809  *     </tr>
810  *     <tr class="deprecated">
811  *       <td>TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA</td>
812  *       <td>20-22</td>
813  *       <td></td>
814  *     </tr>
815  *     <tr class="deprecated">
816  *       <td>TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA384</td>
817  *       <td>20-22</td>
818  *       <td></td>
819  *     </tr>
820  *     <tr class="deprecated">
821  *       <td>TLS_ECDH_ECDSA_WITH_AES_256_GCM_SHA384</td>
822  *       <td>20-22</td>
823  *       <td></td>
824  *     </tr>
825  *     <tr class="deprecated">
826  *       <td>TLS_ECDH_ECDSA_WITH_NULL_SHA</td>
827  *       <td>20-22</td>
828  *       <td></td>
829  *     </tr>
830  *     <tr class="deprecated">
831  *       <td>TLS_ECDH_ECDSA_WITH_RC4_128_SHA</td>
832  *       <td>20-22</td>
833  *       <td></td>
834  *     </tr>
835  *     <tr class="deprecated">
836  *       <td>TLS_ECDH_RSA_WITH_3DES_EDE_CBC_SHA</td>
837  *       <td>20-22</td>
838  *       <td></td>
839  *     </tr>
840  *     <tr class="deprecated">
841  *       <td>TLS_ECDH_RSA_WITH_AES_128_CBC_SHA</td>
842  *       <td>20-22</td>
843  *       <td></td>
844  *     </tr>
845  *     <tr class="deprecated">
846  *       <td>TLS_ECDH_RSA_WITH_AES_128_CBC_SHA256</td>
847  *       <td>20-22</td>
848  *       <td></td>
849  *     </tr>
850  *     <tr class="deprecated">
851  *       <td>TLS_ECDH_RSA_WITH_AES_128_GCM_SHA256</td>
852  *       <td>20-22</td>
853  *       <td></td>
854  *     </tr>
855  *     <tr class="deprecated">
856  *       <td>TLS_ECDH_RSA_WITH_AES_256_CBC_SHA</td>
857  *       <td>20-22</td>
858  *       <td></td>
859  *     </tr>
860  *     <tr class="deprecated">
861  *       <td>TLS_ECDH_RSA_WITH_AES_256_CBC_SHA384</td>
862  *       <td>20-22</td>
863  *       <td></td>
864  *     </tr>
865  *     <tr class="deprecated">
866  *       <td>TLS_ECDH_RSA_WITH_AES_256_GCM_SHA384</td>
867  *       <td>20-22</td>
868  *       <td></td>
869  *     </tr>
870  *     <tr class="deprecated">
871  *       <td>TLS_ECDH_RSA_WITH_NULL_SHA</td>
872  *       <td>20-22</td>
873  *       <td></td>
874  *     </tr>
875  *     <tr class="deprecated">
876  *       <td>TLS_ECDH_RSA_WITH_RC4_128_SHA</td>
877  *       <td>20-22</td>
878  *       <td></td>
879  *     </tr>
880  *     <tr class="deprecated">
881  *       <td>TLS_ECDH_anon_WITH_3DES_EDE_CBC_SHA</td>
882  *       <td>20-22</td>
883  *       <td></td>
884  *     </tr>
885  *     <tr class="deprecated">
886  *       <td>TLS_ECDH_anon_WITH_AES_128_CBC_SHA</td>
887  *       <td>20-22</td>
888  *       <td></td>
889  *     </tr>
890  *     <tr class="deprecated">
891  *       <td>TLS_ECDH_anon_WITH_AES_256_CBC_SHA</td>
892  *       <td>20-22</td>
893  *       <td></td>
894  *     </tr>
895  *     <tr class="deprecated">
896  *       <td>TLS_ECDH_anon_WITH_NULL_SHA</td>
897  *       <td>20-22</td>
898  *       <td></td>
899  *     </tr>
900  *     <tr class="deprecated">
901  *       <td>TLS_ECDH_anon_WITH_RC4_128_SHA</td>
902  *       <td>20-22</td>
903  *       <td></td>
904  *     </tr>
905  *     <tr>
906  *       <td>TLS_EMPTY_RENEGOTIATION_INFO_SCSV</td>
907  *       <td>20+</td>
908  *       <td>20+</td>
909  *     </tr>
910  *     <tr>
911  *       <td>TLS_FALLBACK_SCSV</td>
912  *       <td>21+</td>
913  *       <td></td>
914  *     </tr>
915  *     <tr class="deprecated">
916  *       <td>TLS_NULL_WITH_NULL_NULL</td>
917  *       <td>1-8</td>
918  *       <td></td>
919  *     </tr>
920  *     <tr class="deprecated">
921  *       <td>TLS_PSK_WITH_3DES_EDE_CBC_SHA</td>
922  *       <td>21-22</td>
923  *       <td></td>
924  *     </tr>
925  *     <tr>
926  *       <td>TLS_PSK_WITH_AES_128_CBC_SHA</td>
927  *       <td>21+</td>
928  *       <td>21+</td>
929  *     </tr>
930  *     <tr>
931  *       <td>TLS_PSK_WITH_AES_256_CBC_SHA</td>
932  *       <td>21+</td>
933  *       <td>21+</td>
934  *     </tr>
935  *     <tr class="deprecated">
936  *       <td>TLS_PSK_WITH_RC4_128_SHA</td>
937  *       <td>21-25</td>
938  *       <td></td>
939  *     </tr>
940  *     <tr class="deprecated">
941  *       <td>TLS_RSA_EXPORT_WITH_DES40_CBC_SHA</td>
942  *       <td>1-8</td>
943  *       <td>1-8</td>
944  *     </tr>
945  *     <tr class="deprecated">
946  *       <td>TLS_RSA_WITH_3DES_EDE_CBC_SHA</td>
947  *       <td>1-8</td>
948  *       <td>1-8</td>
949  *     </tr>
950  *     <tr>
951  *       <td>TLS_RSA_WITH_AES_128_CBC_SHA</td>
952  *       <td>9+</td>
953  *       <td>9+</td>
954  *     </tr>
955  *     <tr>
956  *       <td>TLS_RSA_WITH_AES_128_CBC_SHA256</td>
957  *       <td>20+</td>
958  *       <td></td>
959  *     </tr>
960  *     <tr>
961  *       <td>TLS_RSA_WITH_AES_128_GCM_SHA256</td>
962  *       <td>20+</td>
963  *       <td>20+</td>
964  *     </tr>
965  *     <tr>
966  *       <td>TLS_RSA_WITH_AES_256_CBC_SHA</td>
967  *       <td>9+</td>
968  *       <td>20+</td>
969  *     </tr>
970  *     <tr>
971  *       <td>TLS_RSA_WITH_AES_256_CBC_SHA256</td>
972  *       <td>20+</td>
973  *       <td></td>
974  *     </tr>
975  *     <tr>
976  *       <td>TLS_RSA_WITH_AES_256_GCM_SHA384</td>
977  *       <td>20+</td>
978  *       <td>20+</td>
979  *     </tr>
980  *     <tr class="deprecated">
981  *       <td>TLS_RSA_WITH_DES_CBC_SHA</td>
982  *       <td>1-8</td>
983  *       <td>1-8</td>
984  *     </tr>
985  *     <tr class="deprecated">
986  *       <td>TLS_RSA_WITH_NULL_MD5</td>
987  *       <td>1-8</td>
988  *       <td></td>
989  *     </tr>
990  *     <tr class="deprecated">
991  *       <td>TLS_RSA_WITH_NULL_SHA</td>
992  *       <td>1-8</td>
993  *       <td></td>
994  *     </tr>
995  *     <tr class="deprecated">
996  *       <td>TLS_RSA_WITH_NULL_SHA256</td>
997  *       <td>20-22</td>
998  *       <td></td>
999  *     </tr>
1000  *   </tbody>
1001  * </table>
1002  *
1003  * <p><em>NOTE</em>: PSK cipher suites are enabled by default only if the {@code SSLContext} through
1004  * which the engine was created has been initialized with a {@code PSKKeyManager}.
1005  *
1006  * @see SSLContext
1007  * @see SSLSocket
1008  * @see SSLServerSocket
1009  * @see SSLSession
1010  * @see java.net.Socket
1011  *
1012  * @since 1.5
1013  * @author Brad R. Wetmore
1014  */
1015 
1016 public abstract class SSLEngine {
1017 
1018     private String peerHost = null;
1019     private int peerPort = -1;
1020 
1021     /**
1022      * Constructor for an <code>SSLEngine</code> providing no hints
1023      * for an internal session reuse strategy.
1024      *
1025      * @see     SSLContext#createSSLEngine()
1026      * @see     SSLSessionContext
1027      */
SSLEngine()1028     protected SSLEngine() {
1029     }
1030 
1031     /**
1032      * Constructor for an <code>SSLEngine</code>.
1033      * <P>
1034      * <code>SSLEngine</code> implementations may use the
1035      * <code>peerHost</code> and <code>peerPort</code> parameters as hints
1036      * for their internal session reuse strategy.
1037      * <P>
1038      * Some cipher suites (such as Kerberos) require remote hostname
1039      * information. Implementations of this class should use this
1040      * constructor to use Kerberos.
1041      * <P>
1042      * The parameters are not authenticated by the
1043      * <code>SSLEngine</code>.
1044      *
1045      * @param   peerHost the name of the peer host
1046      * @param   peerPort the port number of the peer
1047      * @see     SSLContext#createSSLEngine(String, int)
1048      * @see     SSLSessionContext
1049      */
SSLEngine(String peerHost, int peerPort)1050     protected SSLEngine(String peerHost, int peerPort) {
1051         this.peerHost = peerHost;
1052         this.peerPort = peerPort;
1053     }
1054 
1055     /**
1056      * Returns the host name of the peer.
1057      * <P>
1058      * Note that the value is not authenticated, and should not be
1059      * relied upon.
1060      *
1061      * @return  the host name of the peer, or null if nothing is
1062      *          available.
1063      */
getPeerHost()1064     public String getPeerHost() {
1065         return peerHost;
1066     }
1067 
1068     /**
1069      * Returns the port number of the peer.
1070      * <P>
1071      * Note that the value is not authenticated, and should not be
1072      * relied upon.
1073      *
1074      * @return  the port number of the peer, or -1 if nothing is
1075      *          available.
1076      */
getPeerPort()1077     public int getPeerPort() {
1078         return peerPort;
1079     }
1080 
1081     /**
1082      * Attempts to encode a buffer of plaintext application data into
1083      * SSL/TLS network data.
1084      * <P>
1085      * An invocation of this method behaves in exactly the same manner
1086      * as the invocation:
1087      * <blockquote><pre>
1088      * {@link #wrap(ByteBuffer [], int, int, ByteBuffer)
1089      *     engine.wrap(new ByteBuffer [] { src }, 0, 1, dst);}
1090      * </pre></blockquote>
1091      *
1092      * @param   src
1093      *          a <code>ByteBuffer</code> containing outbound application data
1094      * @param   dst
1095      *          a <code>ByteBuffer</code> to hold outbound network data
1096      * @return  an <code>SSLEngineResult</code> describing the result
1097      *          of this operation.
1098      * @throws  SSLException
1099      *          A problem was encountered while processing the
1100      *          data that caused the <code>SSLEngine</code> to abort.
1101      *          See the class description for more information on
1102      *          engine closure.
1103      * @throws  ReadOnlyBufferException
1104      *          if the <code>dst</code> buffer is read-only.
1105      * @throws  IllegalArgumentException
1106      *          if either <code>src</code> or <code>dst</code>
1107      *          is null.
1108      * @throws  IllegalStateException if the client/server mode
1109      *          has not yet been set.
1110      * @see     #wrap(ByteBuffer [], int, int, ByteBuffer)
1111      */
wrap(ByteBuffer src, ByteBuffer dst)1112     public SSLEngineResult wrap(ByteBuffer src,
1113             ByteBuffer dst) throws SSLException {
1114         return wrap(new ByteBuffer [] { src }, 0, 1, dst);
1115     }
1116 
1117     /**
1118      * Attempts to encode plaintext bytes from a sequence of data
1119      * buffers into SSL/TLS network data.
1120      * <P>
1121      * An invocation of this method behaves in exactly the same manner
1122      * as the invocation:
1123      * <blockquote><pre>
1124      * {@link #wrap(ByteBuffer [], int, int, ByteBuffer)
1125      *     engine.wrap(srcs, 0, srcs.length, dst);}
1126      * </pre></blockquote>
1127      *
1128      * @param   srcs
1129      *          an array of <code>ByteBuffers</code> containing the
1130      *          outbound application data
1131      * @param   dst
1132      *          a <code>ByteBuffer</code> to hold outbound network data
1133      * @return  an <code>SSLEngineResult</code> describing the result
1134      *          of this operation.
1135      * @throws  SSLException
1136      *          A problem was encountered while processing the
1137      *          data that caused the <code>SSLEngine</code> to abort.
1138      *          See the class description for more information on
1139      *          engine closure.
1140      * @throws  ReadOnlyBufferException
1141      *          if the <code>dst</code> buffer is read-only.
1142      * @throws  IllegalArgumentException
1143      *          if either <code>srcs</code> or <code>dst</code>
1144      *          is null, or if any element in <code>srcs</code> is null.
1145      * @throws  IllegalStateException if the client/server mode
1146      *          has not yet been set.
1147      * @see     #wrap(ByteBuffer [], int, int, ByteBuffer)
1148      */
wrap(ByteBuffer [] srcs, ByteBuffer dst)1149     public SSLEngineResult wrap(ByteBuffer [] srcs,
1150             ByteBuffer dst) throws SSLException {
1151         if (srcs == null) {
1152             throw new IllegalArgumentException("src == null");
1153         }
1154         return wrap(srcs, 0, srcs.length, dst);
1155     }
1156 
1157 
1158     /**
1159      * Attempts to encode plaintext bytes from a subsequence of data
1160      * buffers into SSL/TLS network data.  This <i>"gathering"</i>
1161      * operation encodes, in a single invocation, a sequence of bytes
1162      * from one or more of a given sequence of buffers.  Gathering
1163      * wraps are often useful when implementing network protocols or
1164      * file formats that, for example, group data into segments
1165      * consisting of one or more fixed-length headers followed by a
1166      * variable-length body.  See
1167      * {@link java.nio.channels.GatheringByteChannel} for more
1168      * information on gathering, and {@link
1169      * java.nio.channels.GatheringByteChannel#write(ByteBuffer[],
1170      * int, int)} for more information on the subsequence
1171      * behavior.
1172      * <P>
1173      * Depending on the state of the SSLEngine, this method may produce
1174      * network data without consuming any application data (for example,
1175      * it may generate handshake data.)
1176      * <P>
1177      * The application is responsible for reliably transporting the
1178      * network data to the peer, and for ensuring that data created by
1179      * multiple calls to wrap() is transported in the same order in which
1180      * it was generated.  The application must properly synchronize
1181      * multiple calls to this method.
1182      * <P>
1183      * If this <code>SSLEngine</code> has not yet started its initial
1184      * handshake, this method will automatically start the handshake.
1185      * <P>
1186      * This method will attempt to produce one SSL/TLS packet, and will
1187      * consume as much source data as possible, but will never consume
1188      * more than the sum of the bytes remaining in each buffer.  Each
1189      * <code>ByteBuffer</code>'s position is updated to reflect the
1190      * amount of data consumed or produced.  The limits remain the
1191      * same.
1192      * <P>
1193      * The underlying memory used by the <code>srcs</code> and
1194      * <code>dst ByteBuffer</code>s must not be the same.
1195      * <P>
1196      * See the class description for more information on engine closure.
1197      *
1198      * @param   srcs
1199      *          an array of <code>ByteBuffers</code> containing the
1200      *          outbound application data
1201      * @param   offset
1202      *          The offset within the buffer array of the first buffer from
1203      *          which bytes are to be retrieved; it must be non-negative
1204      *          and no larger than <code>srcs.length</code>
1205      * @param   length
1206      *          The maximum number of buffers to be accessed; it must be
1207      *          non-negative and no larger than
1208      *          <code>srcs.length</code>&nbsp;-&nbsp;<code>offset</code>
1209      * @param   dst
1210      *          a <code>ByteBuffer</code> to hold outbound network data
1211      * @return  an <code>SSLEngineResult</code> describing the result
1212      *          of this operation.
1213      * @throws  SSLException
1214      *          A problem was encountered while processing the
1215      *          data that caused the <code>SSLEngine</code> to abort.
1216      *          See the class description for more information on
1217      *          engine closure.
1218      * @throws  IndexOutOfBoundsException
1219      *          if the preconditions on the <code>offset</code> and
1220      *          <code>length</code> parameters do not hold.
1221      * @throws  ReadOnlyBufferException
1222      *          if the <code>dst</code> buffer is read-only.
1223      * @throws  IllegalArgumentException
1224      *          if either <code>srcs</code> or <code>dst</code>
1225      *          is null, or if any element in the <code>srcs</code>
1226      *          subsequence specified is null.
1227      * @throws  IllegalStateException if the client/server mode
1228      *          has not yet been set.
1229      * @see     java.nio.channels.GatheringByteChannel
1230      * @see     java.nio.channels.GatheringByteChannel#write(
1231      *              ByteBuffer[], int, int)
1232      */
wrap(ByteBuffer [] srcs, int offset, int length, ByteBuffer dst)1233     public abstract SSLEngineResult wrap(ByteBuffer [] srcs, int offset,
1234             int length, ByteBuffer dst) throws SSLException;
1235 
1236     /**
1237      * Attempts to decode SSL/TLS network data into a plaintext
1238      * application data buffer.
1239      * <P>
1240      * An invocation of this method behaves in exactly the same manner
1241      * as the invocation:
1242      * <blockquote><pre>
1243      * {@link #unwrap(ByteBuffer, ByteBuffer [], int, int)
1244      *     engine.unwrap(src, new ByteBuffer [] { dst }, 0, 1);}
1245      * </pre></blockquote>
1246      *
1247      * @param   src
1248      *          a <code>ByteBuffer</code> containing inbound network data.
1249      * @param   dst
1250      *          a <code>ByteBuffer</code> to hold inbound application data.
1251      * @return  an <code>SSLEngineResult</code> describing the result
1252      *          of this operation.
1253      * @throws  SSLException
1254      *          A problem was encountered while processing the
1255      *          data that caused the <code>SSLEngine</code> to abort.
1256      *          See the class description for more information on
1257      *          engine closure.
1258      * @throws  ReadOnlyBufferException
1259      *          if the <code>dst</code> buffer is read-only.
1260      * @throws  IllegalArgumentException
1261      *          if either <code>src</code> or <code>dst</code>
1262      *          is null.
1263      * @throws  IllegalStateException if the client/server mode
1264      *          has not yet been set.
1265      * @see     #unwrap(ByteBuffer, ByteBuffer [], int, int)
1266      */
unwrap(ByteBuffer src, ByteBuffer dst)1267     public SSLEngineResult unwrap(ByteBuffer src,
1268             ByteBuffer dst) throws SSLException {
1269         return unwrap(src, new ByteBuffer [] { dst }, 0, 1);
1270     }
1271 
1272     /**
1273      * Attempts to decode SSL/TLS network data into a sequence of plaintext
1274      * application data buffers.
1275      * <P>
1276      * An invocation of this method behaves in exactly the same manner
1277      * as the invocation:
1278      * <blockquote><pre>
1279      * {@link #unwrap(ByteBuffer, ByteBuffer [], int, int)
1280      *     engine.unwrap(src, dsts, 0, dsts.length);}
1281      * </pre></blockquote>
1282      *
1283      * @param   src
1284      *          a <code>ByteBuffer</code> containing inbound network data.
1285      * @param   dsts
1286      *          an array of <code>ByteBuffer</code>s to hold inbound
1287      *          application data.
1288      * @return  an <code>SSLEngineResult</code> describing the result
1289      *          of this operation.
1290      * @throws  SSLException
1291      *          A problem was encountered while processing the
1292      *          data that caused the <code>SSLEngine</code> to abort.
1293      *          See the class description for more information on
1294      *          engine closure.
1295      * @throws  ReadOnlyBufferException
1296      *          if any of the <code>dst</code> buffers are read-only.
1297      * @throws  IllegalArgumentException
1298      *          if either <code>src</code> or <code>dsts</code>
1299      *          is null, or if any element in <code>dsts</code> is null.
1300      * @throws  IllegalStateException if the client/server mode
1301      *          has not yet been set.
1302      * @see     #unwrap(ByteBuffer, ByteBuffer [], int, int)
1303      */
unwrap(ByteBuffer src, ByteBuffer [] dsts)1304     public SSLEngineResult unwrap(ByteBuffer src,
1305             ByteBuffer [] dsts) throws SSLException {
1306         if (dsts == null) {
1307             throw new IllegalArgumentException("dsts == null");
1308         }
1309         return unwrap(src, dsts, 0, dsts.length);
1310     }
1311 
1312     /**
1313      * Attempts to decode SSL/TLS network data into a subsequence of
1314      * plaintext application data buffers.  This <i>"scattering"</i>
1315      * operation decodes, in a single invocation, a sequence of bytes
1316      * into one or more of a given sequence of buffers.  Scattering
1317      * unwraps are often useful when implementing network protocols or
1318      * file formats that, for example, group data into segments
1319      * consisting of one or more fixed-length headers followed by a
1320      * variable-length body.  See
1321      * {@link java.nio.channels.ScatteringByteChannel} for more
1322      * information on scattering, and {@link
1323      * java.nio.channels.ScatteringByteChannel#read(ByteBuffer[],
1324      * int, int)} for more information on the subsequence
1325      * behavior.
1326      * <P>
1327      * Depending on the state of the SSLEngine, this method may consume
1328      * network data without producing any application data (for example,
1329      * it may consume handshake data.)
1330      * <P>
1331      * The application is responsible for reliably obtaining the network
1332      * data from the peer, and for invoking unwrap() on the data in the
1333      * order it was received.  The application must properly synchronize
1334      * multiple calls to this method.
1335      * <P>
1336      * If this <code>SSLEngine</code> has not yet started its initial
1337      * handshake, this method will automatically start the handshake.
1338      * <P>
1339      * This method will attempt to consume one complete SSL/TLS network
1340      * packet, but will never consume more than the sum of the bytes
1341      * remaining in the buffers.  Each <code>ByteBuffer</code>'s
1342      * position is updated to reflect the amount of data consumed or
1343      * produced.  The limits remain the same.
1344      * <P>
1345      * The underlying memory used by the <code>src</code> and
1346      * <code>dsts ByteBuffer</code>s must not be the same.
1347      * <P>
1348      * The inbound network buffer may be modified as a result of this
1349      * call:  therefore if the network data packet is required for some
1350      * secondary purpose, the data should be duplicated before calling this
1351      * method.  Note:  the network data will not be useful to a second
1352      * SSLEngine, as each SSLEngine contains unique random state which
1353      * influences the SSL/TLS messages.
1354      * <P>
1355      * See the class description for more information on engine closure.
1356      *
1357      * @param   src
1358      *          a <code>ByteBuffer</code> containing inbound network data.
1359      * @param   dsts
1360      *          an array of <code>ByteBuffer</code>s to hold inbound
1361      *          application data.
1362      * @param   offset
1363      *          The offset within the buffer array of the first buffer from
1364      *          which bytes are to be transferred; it must be non-negative
1365      *          and no larger than <code>dsts.length</code>.
1366      * @param   length
1367      *          The maximum number of buffers to be accessed; it must be
1368      *          non-negative and no larger than
1369      *          <code>dsts.length</code>&nbsp;-&nbsp;<code>offset</code>.
1370      * @return  an <code>SSLEngineResult</code> describing the result
1371      *          of this operation.
1372      * @throws  SSLException
1373      *          A problem was encountered while processing the
1374      *          data that caused the <code>SSLEngine</code> to abort.
1375      *          See the class description for more information on
1376      *          engine closure.
1377      * @throws  IndexOutOfBoundsException
1378      *          If the preconditions on the <code>offset</code> and
1379      *          <code>length</code> parameters do not hold.
1380      * @throws  ReadOnlyBufferException
1381      *          if any of the <code>dst</code> buffers are read-only.
1382      * @throws  IllegalArgumentException
1383      *          if either <code>src</code> or <code>dsts</code>
1384      *          is null, or if any element in the <code>dsts</code>
1385      *          subsequence specified is null.
1386      * @throws  IllegalStateException if the client/server mode
1387      *          has not yet been set.
1388      * @see     java.nio.channels.ScatteringByteChannel
1389      * @see     java.nio.channels.ScatteringByteChannel#read(
1390      *              ByteBuffer[], int, int)
1391      */
unwrap(ByteBuffer src, ByteBuffer [] dsts, int offset, int length)1392     public abstract SSLEngineResult unwrap(ByteBuffer src,
1393             ByteBuffer [] dsts, int offset, int length) throws SSLException;
1394 
1395 
1396     /**
1397      * Returns a delegated <code>Runnable</code> task for
1398      * this <code>SSLEngine</code>.
1399      * <P>
1400      * <code>SSLEngine</code> operations may require the results of
1401      * operations that block, or may take an extended period of time to
1402      * complete.  This method is used to obtain an outstanding {@link
1403      * java.lang.Runnable} operation (task).  Each task must be assigned
1404      * a thread (possibly the current) to perform the {@link
1405      * java.lang.Runnable#run() run} operation.  Once the
1406      * <code>run</code> method returns, the <code>Runnable</code> object
1407      * is no longer needed and may be discarded.
1408      * <P>
1409      * Delegated tasks run in the <code>AccessControlContext</code>
1410      * in place when this object was created.
1411      * <P>
1412      * A call to this method will return each outstanding task
1413      * exactly once.
1414      * <P>
1415      * Multiple delegated tasks can be run in parallel.
1416      *
1417      * @return  a delegated <code>Runnable</code> task, or null
1418      *          if none are available.
1419      */
getDelegatedTask()1420     public abstract Runnable getDelegatedTask();
1421 
1422 
1423     /**
1424      * Signals that no more inbound network data will be sent
1425      * to this <code>SSLEngine</code>.
1426      * <P>
1427      * If the application initiated the closing process by calling
1428      * {@link #closeOutbound()}, under some circumstances it is not
1429      * required that the initiator wait for the peer's corresponding
1430      * close message.  (See section 7.2.1 of the TLS specification (<A
1431      * HREF="http://www.ietf.org/rfc/rfc2246.txt">RFC 2246</A>) for more
1432      * information on waiting for closure alerts.)  In such cases, this
1433      * method need not be called.
1434      * <P>
1435      * But if the application did not initiate the closure process, or
1436      * if the circumstances above do not apply, this method should be
1437      * called whenever the end of the SSL/TLS data stream is reached.
1438      * This ensures closure of the inbound side, and checks that the
1439      * peer followed the SSL/TLS close procedure properly, thus
1440      * detecting possible truncation attacks.
1441      * <P>
1442      * This method is idempotent:  if the inbound side has already
1443      * been closed, this method does not do anything.
1444      * <P>
1445      * {@link #wrap(ByteBuffer, ByteBuffer) wrap()} should be
1446      * called to flush any remaining handshake data.
1447      *
1448      * @throws  SSLException
1449      *          if this engine has not received the proper SSL/TLS close
1450      *          notification message from the peer.
1451      *
1452      * @see     #isInboundDone()
1453      * @see     #isOutboundDone()
1454      */
closeInbound()1455     public abstract void closeInbound() throws SSLException;
1456 
1457 
1458     /**
1459      * Returns whether {@link #unwrap(ByteBuffer, ByteBuffer)} will
1460      * accept any more inbound data messages.
1461      *
1462      * @return  true if the <code>SSLEngine</code> will not
1463      *          consume anymore network data (and by implication,
1464      *          will not produce any more application data.)
1465      * @see     #closeInbound()
1466      */
isInboundDone()1467     public abstract boolean isInboundDone();
1468 
1469 
1470     /**
1471      * Signals that no more outbound application data will be sent
1472      * on this <code>SSLEngine</code>.
1473      * <P>
1474      * This method is idempotent:  if the outbound side has already
1475      * been closed, this method does not do anything.
1476      * <P>
1477      * {@link #wrap(ByteBuffer, ByteBuffer)} should be
1478      * called to flush any remaining handshake data.
1479      *
1480      * @see     #isOutboundDone()
1481      */
closeOutbound()1482     public abstract void closeOutbound();
1483 
1484 
1485     /**
1486      * Returns whether {@link #wrap(ByteBuffer, ByteBuffer)} will
1487      * produce any more outbound data messages.
1488      * <P>
1489      * Note that during the closure phase, a <code>SSLEngine</code> may
1490      * generate handshake closure data that must be sent to the peer.
1491      * <code>wrap()</code> must be called to generate this data.  When
1492      * this method returns true, no more outbound data will be created.
1493      *
1494      * @return  true if the <code>SSLEngine</code> will not produce
1495      *          any more network data
1496      *
1497      * @see     #closeOutbound()
1498      * @see     #closeInbound()
1499      */
isOutboundDone()1500     public abstract boolean isOutboundDone();
1501 
1502 
1503     /**
1504      * Returns the names of the cipher suites which could be enabled for use
1505      * on this engine.  Normally, only a subset of these will actually
1506      * be enabled by default, since this list may include cipher suites which
1507      * do not meet quality of service requirements for those defaults.  Such
1508      * cipher suites might be useful in specialized applications.
1509      *
1510      * @return  an array of cipher suite names
1511      * @see     #getEnabledCipherSuites()
1512      * @see     #setEnabledCipherSuites(String [])
1513      */
getSupportedCipherSuites()1514     public abstract String [] getSupportedCipherSuites();
1515 
1516 
1517     /**
1518      * Returns the names of the SSL cipher suites which are currently
1519      * enabled for use on this engine.  When an SSLEngine is first
1520      * created, all enabled cipher suites support a minimum quality of
1521      * service.  Thus, in some environments this value might be empty.
1522      * <P>
1523      * Even if a suite has been enabled, it might never be used.  (For
1524      * example, the peer does not support it, the requisite
1525      * certificates/private keys for the suite are not available, or an
1526      * anonymous suite is enabled but authentication is required.)
1527      *
1528      * @return  an array of cipher suite names
1529      * @see     #getSupportedCipherSuites()
1530      * @see     #setEnabledCipherSuites(String [])
1531      */
getEnabledCipherSuites()1532     public abstract String [] getEnabledCipherSuites();
1533 
1534 
1535     /**
1536      * Sets the cipher suites enabled for use on this engine.
1537      * <P>
1538      * Each cipher suite in the <code>suites</code> parameter must have
1539      * been listed by getSupportedCipherSuites(), or the method will
1540      * fail.  Following a successful call to this method, only suites
1541      * listed in the <code>suites</code> parameter are enabled for use.
1542      * <P>
1543      * See {@link #getEnabledCipherSuites()} for more information
1544      * on why a specific cipher suite may never be used on a engine.
1545      *
1546      * @param   suites Names of all the cipher suites to enable
1547      * @throws  IllegalArgumentException when one or more of the ciphers
1548      *          named by the parameter is not supported, or when the
1549      *          parameter is null.
1550      * @see     #getSupportedCipherSuites()
1551      * @see     #getEnabledCipherSuites()
1552      */
setEnabledCipherSuites(String suites [])1553     public abstract void setEnabledCipherSuites(String suites []);
1554 
1555 
1556     /**
1557      * Returns the names of the protocols which could be enabled for use
1558      * with this <code>SSLEngine</code>.
1559      *
1560      * @return  an array of protocols supported
1561      */
getSupportedProtocols()1562     public abstract String [] getSupportedProtocols();
1563 
1564 
1565     /**
1566      * Returns the names of the protocol versions which are currently
1567      * enabled for use with this <code>SSLEngine</code>.
1568      *
1569      * @return  an array of protocols
1570      * @see     #setEnabledProtocols(String [])
1571      */
getEnabledProtocols()1572     public abstract String [] getEnabledProtocols();
1573 
1574 
1575     /**
1576      * Set the protocol versions enabled for use on this engine.
1577      * <P>
1578      * The protocols must have been listed by getSupportedProtocols()
1579      * as being supported.  Following a successful call to this method,
1580      * only protocols listed in the <code>protocols</code> parameter
1581      * are enabled for use.
1582      *
1583      * @param   protocols Names of all the protocols to enable.
1584      * @throws  IllegalArgumentException when one or more of
1585      *          the protocols named by the parameter is not supported or
1586      *          when the protocols parameter is null.
1587      * @see     #getEnabledProtocols()
1588      */
setEnabledProtocols(String protocols[])1589     public abstract void setEnabledProtocols(String protocols[]);
1590 
1591 
1592     /**
1593      * Returns the <code>SSLSession</code> in use in this
1594      * <code>SSLEngine</code>.
1595      * <P>
1596      * These can be long lived, and frequently correspond to an entire
1597      * login session for some user.  The session specifies a particular
1598      * cipher suite which is being actively used by all connections in
1599      * that session, as well as the identities of the session's client
1600      * and server.
1601      * <P>
1602      * Unlike {@link SSLSocket#getSession()}
1603      * this method does not block until handshaking is complete.
1604      * <P>
1605      * Until the initial handshake has completed, this method returns
1606      * a session object which reports an invalid cipher suite of
1607      * "SSL_NULL_WITH_NULL_NULL".
1608      *
1609      * @return  the <code>SSLSession</code> for this <code>SSLEngine</code>
1610      * @see     SSLSession
1611      */
getSession()1612     public abstract SSLSession getSession();
1613 
1614 
1615     /**
1616      * Returns the {@code SSLSession} being constructed during a SSL/TLS
1617      * handshake.
1618      * <p>
1619      * TLS protocols may negotiate parameters that are needed when using
1620      * an instance of this class, but before the {@code SSLSession} has
1621      * been completely initialized and made available via {@code getSession}.
1622      * For example, the list of valid signature algorithms may restrict
1623      * the type of certificates that can used during TrustManager
1624      * decisions, or the maximum TLS fragment packet sizes can be
1625      * resized to better support the network environment.
1626      * <p>
1627      * This method provides early access to the {@code SSLSession} being
1628      * constructed.  Depending on how far the handshake has progressed,
1629      * some data may not yet be available for use.  For example, if a
1630      * remote server will be sending a Certificate chain, but that chain
1631      * has yet not been processed, the {@code getPeerCertificates}
1632      * method of {@code SSLSession} will throw a
1633      * SSLPeerUnverifiedException.  Once that chain has been processed,
1634      * {@code getPeerCertificates} will return the proper value.
1635      *
1636      * @see SSLSocket
1637      * @see SSLSession
1638      * @see ExtendedSSLSession
1639      * @see X509ExtendedKeyManager
1640      * @see X509ExtendedTrustManager
1641      *
1642      * @return null if this instance is not currently handshaking, or
1643      *         if the current handshake has not progressed far enough to
1644      *         create a basic SSLSession.  Otherwise, this method returns the
1645      *         {@code SSLSession} currently being negotiated.
1646      * @throws UnsupportedOperationException if the underlying provider
1647      *         does not implement the operation.
1648      *
1649      * @since 1.7
1650      */
getHandshakeSession()1651     public SSLSession getHandshakeSession() {
1652         throw new UnsupportedOperationException();
1653     }
1654 
1655 
1656     /**
1657      * Initiates handshaking (initial or renegotiation) on this SSLEngine.
1658      * <P>
1659      * This method is not needed for the initial handshake, as the
1660      * <code>wrap()</code> and <code>unwrap()</code> methods will
1661      * implicitly call this method if handshaking has not already begun.
1662      * <P>
1663      * Note that the peer may also request a session renegotiation with
1664      * this <code>SSLEngine</code> by sending the appropriate
1665      * session renegotiate handshake message.
1666      * <P>
1667      * Unlike the {@link SSLSocket#startHandshake()
1668      * SSLSocket#startHandshake()} method, this method does not block
1669      * until handshaking is completed.
1670      * <P>
1671      * To force a complete SSL/TLS session renegotiation, the current
1672      * session should be invalidated prior to calling this method.
1673      * <P>
1674      * Some protocols may not support multiple handshakes on an existing
1675      * engine and may throw an <code>SSLException</code>.
1676      *
1677      * @throws  SSLException
1678      *          if a problem was encountered while signaling the
1679      *          <code>SSLEngine</code> to begin a new handshake.
1680      *          See the class description for more information on
1681      *          engine closure.
1682      * @throws  IllegalStateException if the client/server mode
1683      *          has not yet been set.
1684      * @see     SSLSession#invalidate()
1685      */
beginHandshake()1686     public abstract void beginHandshake() throws SSLException;
1687 
1688 
1689     /**
1690      * Returns the current handshake status for this <code>SSLEngine</code>.
1691      *
1692      * @return  the current <code>SSLEngineResult.HandshakeStatus</code>.
1693      */
getHandshakeStatus()1694     public abstract SSLEngineResult.HandshakeStatus getHandshakeStatus();
1695 
1696 
1697     /**
1698      * Configures the engine to use client (or server) mode when
1699      * handshaking.
1700      * <P>
1701      * This method must be called before any handshaking occurs.
1702      * Once handshaking has begun, the mode can not be reset for the
1703      * life of this engine.
1704      * <P>
1705      * Servers normally authenticate themselves, and clients
1706      * are not required to do so.
1707      *
1708      * @param   mode true if the engine should start its handshaking
1709      *          in "client" mode
1710      * @throws  IllegalArgumentException if a mode change is attempted
1711      *          after the initial handshake has begun.
1712      * @see     #getUseClientMode()
1713      */
setUseClientMode(boolean mode)1714     public abstract void setUseClientMode(boolean mode);
1715 
1716 
1717     /**
1718      * Returns true if the engine is set to use client mode when
1719      * handshaking.
1720      *
1721      * @return  true if the engine should do handshaking
1722      *          in "client" mode
1723      * @see     #setUseClientMode(boolean)
1724      */
getUseClientMode()1725     public abstract boolean getUseClientMode();
1726 
1727 
1728     /**
1729      * Configures the engine to <i>require</i> client authentication.  This
1730      * option is only useful for engines in the server mode.
1731      * <P>
1732      * An engine's client authentication setting is one of the following:
1733      * <ul>
1734      * <li> client authentication required
1735      * <li> client authentication requested
1736      * <li> no client authentication desired
1737      * </ul>
1738      * <P>
1739      * Unlike {@link #setWantClientAuth(boolean)}, if this option is set and
1740      * the client chooses not to provide authentication information
1741      * about itself, <i>the negotiations will stop and the engine will
1742      * begin its closure procedure</i>.
1743      * <P>
1744      * Calling this method overrides any previous setting made by
1745      * this method or {@link #setWantClientAuth(boolean)}.
1746      *
1747      * @param   need set to true if client authentication is required,
1748      *          or false if no client authentication is desired.
1749      * @see     #getNeedClientAuth()
1750      * @see     #setWantClientAuth(boolean)
1751      * @see     #getWantClientAuth()
1752      * @see     #setUseClientMode(boolean)
1753      */
setNeedClientAuth(boolean need)1754     public abstract void setNeedClientAuth(boolean need);
1755 
1756 
1757     /**
1758      * Returns true if the engine will <i>require</i> client authentication.
1759      * This option is only useful to engines in the server mode.
1760      *
1761      * @return  true if client authentication is required,
1762      *          or false if no client authentication is desired.
1763      * @see     #setNeedClientAuth(boolean)
1764      * @see     #setWantClientAuth(boolean)
1765      * @see     #getWantClientAuth()
1766      * @see     #setUseClientMode(boolean)
1767      */
getNeedClientAuth()1768     public abstract boolean getNeedClientAuth();
1769 
1770 
1771     /**
1772      * Configures the engine to <i>request</i> client authentication.
1773      * This option is only useful for engines in the server mode.
1774      * <P>
1775      * An engine's client authentication setting is one of the following:
1776      * <ul>
1777      * <li> client authentication required
1778      * <li> client authentication requested
1779      * <li> no client authentication desired
1780      * </ul>
1781      * <P>
1782      * Unlike {@link #setNeedClientAuth(boolean)}, if this option is set and
1783      * the client chooses not to provide authentication information
1784      * about itself, <i>the negotiations will continue</i>.
1785      * <P>
1786      * Calling this method overrides any previous setting made by
1787      * this method or {@link #setNeedClientAuth(boolean)}.
1788      *
1789      * @param   want set to true if client authentication is requested,
1790      *          or false if no client authentication is desired.
1791      * @see     #getWantClientAuth()
1792      * @see     #setNeedClientAuth(boolean)
1793      * @see     #getNeedClientAuth()
1794      * @see     #setUseClientMode(boolean)
1795      */
setWantClientAuth(boolean want)1796     public abstract void setWantClientAuth(boolean want);
1797 
1798 
1799     /**
1800      * Returns true if the engine will <i>request</i> client authentication.
1801      * This option is only useful for engines in the server mode.
1802      *
1803      * @return  true if client authentication is requested,
1804      *          or false if no client authentication is desired.
1805      * @see     #setNeedClientAuth(boolean)
1806      * @see     #getNeedClientAuth()
1807      * @see     #setWantClientAuth(boolean)
1808      * @see     #setUseClientMode(boolean)
1809      */
getWantClientAuth()1810     public abstract boolean getWantClientAuth();
1811 
1812 
1813     /**
1814      * Controls whether new SSL sessions may be established by this engine.
1815      * If session creations are not allowed, and there are no
1816      * existing sessions to resume, there will be no successful
1817      * handshaking.
1818      *
1819      * @param   flag true indicates that sessions may be created; this
1820      *          is the default.  false indicates that an existing session
1821      *          must be resumed
1822      * @see     #getEnableSessionCreation()
1823      */
setEnableSessionCreation(boolean flag)1824     public abstract void setEnableSessionCreation(boolean flag);
1825 
1826 
1827     /**
1828      * Returns true if new SSL sessions may be established by this engine.
1829      *
1830      * @return  true indicates that sessions may be created; this
1831      *          is the default.  false indicates that an existing session
1832      *          must be resumed
1833      * @see     #setEnableSessionCreation(boolean)
1834      */
getEnableSessionCreation()1835     public abstract boolean getEnableSessionCreation();
1836 
1837     /**
1838      * Returns the SSLParameters in effect for this SSLEngine.
1839      * The ciphersuites and protocols of the returned SSLParameters
1840      * are always non-null.
1841      *
1842      * @return the SSLParameters in effect for this SSLEngine.
1843      * @since 1.6
1844      */
getSSLParameters()1845     public SSLParameters getSSLParameters() {
1846         SSLParameters params = new SSLParameters();
1847         params.setCipherSuites(getEnabledCipherSuites());
1848         params.setProtocols(getEnabledProtocols());
1849         if (getNeedClientAuth()) {
1850             params.setNeedClientAuth(true);
1851         } else if (getWantClientAuth()) {
1852             params.setWantClientAuth(true);
1853         }
1854         return params;
1855     }
1856 
1857     /**
1858      * Applies SSLParameters to this engine.
1859      *
1860      * <p>This means:
1861      * <ul>
1862      * <li>If {@code params.getCipherSuites()} is non-null,
1863      *   {@code setEnabledCipherSuites()} is called with that value.</li>
1864      * <li>If {@code params.getProtocols()} is non-null,
1865      *   {@code setEnabledProtocols()} is called with that value.</li>
1866      * <li>If {@code params.getNeedClientAuth()} or
1867      *   {@code params.getWantClientAuth()} return {@code true},
1868      *   {@code setNeedClientAuth(true)} and
1869      *   {@code setWantClientAuth(true)} are called, respectively;
1870      *   otherwise {@code setWantClientAuth(false)} is called.</li>
1871      * <li>If {@code params.getServerNames()} is non-null, the engine will
1872      *   configure its server names with that value.</li>
1873      * <li>If {@code params.getSNIMatchers()} is non-null, the engine will
1874      *   configure its SNI matchers with that value.</li>
1875      * </ul>
1876      *
1877      * @param params the parameters
1878      * @throws IllegalArgumentException if the setEnabledCipherSuites() or
1879      *    the setEnabledProtocols() call fails
1880      * @since 1.6
1881      */
setSSLParameters(SSLParameters params)1882     public void setSSLParameters(SSLParameters params) {
1883         String[] s;
1884         s = params.getCipherSuites();
1885         if (s != null) {
1886             setEnabledCipherSuites(s);
1887         }
1888         s = params.getProtocols();
1889         if (s != null) {
1890             setEnabledProtocols(s);
1891         }
1892         if (params.getNeedClientAuth()) {
1893             setNeedClientAuth(true);
1894         } else if (params.getWantClientAuth()) {
1895             setWantClientAuth(true);
1896         } else {
1897             setWantClientAuth(false);
1898         }
1899     }
1900 
1901 }
1902