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1 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
2  * All rights reserved.
3  *
4  * This package is an SSL implementation written
5  * by Eric Young (eay@cryptsoft.com).
6  * The implementation was written so as to conform with Netscapes SSL.
7  *
8  * This library is free for commercial and non-commercial use as long as
9  * the following conditions are aheared to.  The following conditions
10  * apply to all code found in this distribution, be it the RC4, RSA,
11  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
12  * included with this distribution is covered by the same copyright terms
13  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
14  *
15  * Copyright remains Eric Young's, and as such any Copyright notices in
16  * the code are not to be removed.
17  * If this package is used in a product, Eric Young should be given attribution
18  * as the author of the parts of the library used.
19  * This can be in the form of a textual message at program startup or
20  * in documentation (online or textual) provided with the package.
21  *
22  * Redistribution and use in source and binary forms, with or without
23  * modification, are permitted provided that the following conditions
24  * are met:
25  * 1. Redistributions of source code must retain the copyright
26  *    notice, this list of conditions and the following disclaimer.
27  * 2. Redistributions in binary form must reproduce the above copyright
28  *    notice, this list of conditions and the following disclaimer in the
29  *    documentation and/or other materials provided with the distribution.
30  * 3. All advertising materials mentioning features or use of this software
31  *    must display the following acknowledgement:
32  *    "This product includes cryptographic software written by
33  *     Eric Young (eay@cryptsoft.com)"
34  *    The word 'cryptographic' can be left out if the rouines from the library
35  *    being used are not cryptographic related :-).
36  * 4. If you include any Windows specific code (or a derivative thereof) from
37  *    the apps directory (application code) you must include an acknowledgement:
38  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
39  *
40  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
41  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
43  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
44  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
45  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
46  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
48  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
49  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
50  * SUCH DAMAGE.
51  *
52  * The licence and distribution terms for any publically available version or
53  * derivative of this code cannot be changed.  i.e. this code cannot simply be
54  * copied and put under another distribution licence
55  * [including the GNU Public Licence.]
56  */
57 /* ====================================================================
58  * Copyright (c) 1998-2007 The OpenSSL Project.  All rights reserved.
59  *
60  * Redistribution and use in source and binary forms, with or without
61  * modification, are permitted provided that the following conditions
62  * are met:
63  *
64  * 1. Redistributions of source code must retain the above copyright
65  *    notice, this list of conditions and the following disclaimer.
66  *
67  * 2. Redistributions in binary form must reproduce the above copyright
68  *    notice, this list of conditions and the following disclaimer in
69  *    the documentation and/or other materials provided with the
70  *    distribution.
71  *
72  * 3. All advertising materials mentioning features or use of this
73  *    software must display the following acknowledgment:
74  *    "This product includes software developed by the OpenSSL Project
75  *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
76  *
77  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
78  *    endorse or promote products derived from this software without
79  *    prior written permission. For written permission, please contact
80  *    openssl-core@openssl.org.
81  *
82  * 5. Products derived from this software may not be called "OpenSSL"
83  *    nor may "OpenSSL" appear in their names without prior written
84  *    permission of the OpenSSL Project.
85  *
86  * 6. Redistributions of any form whatsoever must retain the following
87  *    acknowledgment:
88  *    "This product includes software developed by the OpenSSL Project
89  *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
90  *
91  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
92  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
93  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
94  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
95  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
96  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
97  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
98  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
99  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
100  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
101  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
102  * OF THE POSSIBILITY OF SUCH DAMAGE.
103  * ====================================================================
104  *
105  * This product includes cryptographic software written by Eric Young
106  * (eay@cryptsoft.com).  This product includes software written by Tim
107  * Hudson (tjh@cryptsoft.com).
108  *
109  */
110 /* ====================================================================
111  * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
112  * ECC cipher suite support in OpenSSL originally developed by
113  * SUN MICROSYSTEMS, INC., and contributed to the OpenSSL project.
114  */
115 /* ====================================================================
116  * Copyright 2005 Nokia. All rights reserved.
117  *
118  * The portions of the attached software ("Contribution") is developed by
119  * Nokia Corporation and is licensed pursuant to the OpenSSL open source
120  * license.
121  *
122  * The Contribution, originally written by Mika Kousa and Pasi Eronen of
123  * Nokia Corporation, consists of the "PSK" (Pre-Shared Key) ciphersuites
124  * support (see RFC 4279) to OpenSSL.
125  *
126  * No patent licenses or other rights except those expressly stated in
127  * the OpenSSL open source license shall be deemed granted or received
128  * expressly, by implication, estoppel, or otherwise.
129  *
130  * No assurances are provided by Nokia that the Contribution does not
131  * infringe the patent or other intellectual property rights of any third
132  * party or that the license provides you with all the necessary rights
133  * to make use of the Contribution.
134  *
135  * THE SOFTWARE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. IN
136  * ADDITION TO THE DISCLAIMERS INCLUDED IN THE LICENSE, NOKIA
137  * SPECIFICALLY DISCLAIMS ANY LIABILITY FOR CLAIMS BROUGHT BY YOU OR ANY
138  * OTHER ENTITY BASED ON INFRINGEMENT OF INTELLECTUAL PROPERTY RIGHTS OR
139  * OTHERWISE.
140  */
141 
142 #ifndef OPENSSL_HEADER_SSL_H
143 #define OPENSSL_HEADER_SSL_H
144 
145 #include <openssl/base.h>
146 
147 #include <openssl/bio.h>
148 #include <openssl/buf.h>
149 #include <openssl/pem.h>
150 #include <openssl/span.h>
151 #include <openssl/ssl3.h>
152 #include <openssl/thread.h>
153 #include <openssl/tls1.h>
154 #include <openssl/x509.h>
155 
156 #if !defined(OPENSSL_WINDOWS)
157 #include <sys/time.h>
158 #endif
159 
160 // NGINX needs this #include. Consider revisiting this after NGINX 1.14.0 has
161 // been out for a year or so (assuming that they fix it in that release.) See
162 // https://boringssl-review.googlesource.com/c/boringssl/+/21664.
163 #include <openssl/hmac.h>
164 
165 // Forward-declare struct timeval. On Windows, it is defined in winsock2.h and
166 // Windows headers define too many macros to be included in public headers.
167 // However, only a forward declaration is needed.
168 struct timeval;
169 
170 #if defined(__cplusplus)
171 extern "C" {
172 #endif
173 
174 
175 // SSL implementation.
176 
177 
178 // SSL contexts.
179 //
180 // |SSL_CTX| objects manage shared state and configuration between multiple TLS
181 // or DTLS connections. Whether the connections are TLS or DTLS is selected by
182 // an |SSL_METHOD| on creation.
183 //
184 // |SSL_CTX| are reference-counted and may be shared by connections across
185 // multiple threads. Once shared, functions which change the |SSL_CTX|'s
186 // configuration may not be used.
187 
188 // TLS_method is the |SSL_METHOD| used for TLS connections.
189 OPENSSL_EXPORT const SSL_METHOD *TLS_method(void);
190 
191 // DTLS_method is the |SSL_METHOD| used for DTLS connections.
192 OPENSSL_EXPORT const SSL_METHOD *DTLS_method(void);
193 
194 // TLS_with_buffers_method is like |TLS_method|, but avoids all use of
195 // crypto/x509. All client connections created with |TLS_with_buffers_method|
196 // will fail unless a certificate verifier is installed with
197 // |SSL_set_custom_verify| or |SSL_CTX_set_custom_verify|.
198 OPENSSL_EXPORT const SSL_METHOD *TLS_with_buffers_method(void);
199 
200 // DTLS_with_buffers_method is like |DTLS_method|, but avoids all use of
201 // crypto/x509.
202 OPENSSL_EXPORT const SSL_METHOD *DTLS_with_buffers_method(void);
203 
204 // SSL_CTX_new returns a newly-allocated |SSL_CTX| with default settings or NULL
205 // on error.
206 OPENSSL_EXPORT SSL_CTX *SSL_CTX_new(const SSL_METHOD *method);
207 
208 // SSL_CTX_up_ref increments the reference count of |ctx|. It returns one.
209 OPENSSL_EXPORT int SSL_CTX_up_ref(SSL_CTX *ctx);
210 
211 // SSL_CTX_free releases memory associated with |ctx|.
212 OPENSSL_EXPORT void SSL_CTX_free(SSL_CTX *ctx);
213 
214 
215 // SSL connections.
216 //
217 // An |SSL| object represents a single TLS or DTLS connection. Although the
218 // shared |SSL_CTX| is thread-safe, an |SSL| is not thread-safe and may only be
219 // used on one thread at a time.
220 
221 // SSL_new returns a newly-allocated |SSL| using |ctx| or NULL on error. The new
222 // connection inherits settings from |ctx| at the time of creation. Settings may
223 // also be individually configured on the connection.
224 //
225 // On creation, an |SSL| is not configured to be either a client or server. Call
226 // |SSL_set_connect_state| or |SSL_set_accept_state| to set this.
227 OPENSSL_EXPORT SSL *SSL_new(SSL_CTX *ctx);
228 
229 // SSL_free releases memory associated with |ssl|.
230 OPENSSL_EXPORT void SSL_free(SSL *ssl);
231 
232 // SSL_get_SSL_CTX returns the |SSL_CTX| associated with |ssl|. If
233 // |SSL_set_SSL_CTX| is called, it returns the new |SSL_CTX|, not the initial
234 // one.
235 OPENSSL_EXPORT SSL_CTX *SSL_get_SSL_CTX(const SSL *ssl);
236 
237 // SSL_set_connect_state configures |ssl| to be a client.
238 OPENSSL_EXPORT void SSL_set_connect_state(SSL *ssl);
239 
240 // SSL_set_accept_state configures |ssl| to be a server.
241 OPENSSL_EXPORT void SSL_set_accept_state(SSL *ssl);
242 
243 // SSL_is_server returns one if |ssl| is configured as a server and zero
244 // otherwise.
245 OPENSSL_EXPORT int SSL_is_server(const SSL *ssl);
246 
247 // SSL_is_dtls returns one if |ssl| is a DTLS connection and zero otherwise.
248 OPENSSL_EXPORT int SSL_is_dtls(const SSL *ssl);
249 
250 // SSL_set_bio configures |ssl| to read from |rbio| and write to |wbio|. |ssl|
251 // takes ownership of the two |BIO|s. If |rbio| and |wbio| are the same, |ssl|
252 // only takes ownership of one reference.
253 //
254 // In DTLS, |rbio| must be non-blocking to properly handle timeouts and
255 // retransmits.
256 //
257 // If |rbio| is the same as the currently configured |BIO| for reading, that
258 // side is left untouched and is not freed.
259 //
260 // If |wbio| is the same as the currently configured |BIO| for writing AND |ssl|
261 // is not currently configured to read from and write to the same |BIO|, that
262 // side is left untouched and is not freed. This asymmetry is present for
263 // historical reasons.
264 //
265 // Due to the very complex historical behavior of this function, calling this
266 // function if |ssl| already has |BIO|s configured is deprecated. Prefer
267 // |SSL_set0_rbio| and |SSL_set0_wbio| instead.
268 OPENSSL_EXPORT void SSL_set_bio(SSL *ssl, BIO *rbio, BIO *wbio);
269 
270 // SSL_set0_rbio configures |ssl| to read from |rbio|. It takes ownership of
271 // |rbio|.
272 //
273 // Note that, although this function and |SSL_set0_wbio| may be called on the
274 // same |BIO|, each call takes a reference. Use |BIO_up_ref| to balance this.
275 OPENSSL_EXPORT void SSL_set0_rbio(SSL *ssl, BIO *rbio);
276 
277 // SSL_set0_wbio configures |ssl| to write to |wbio|. It takes ownership of
278 // |wbio|.
279 //
280 // Note that, although this function and |SSL_set0_rbio| may be called on the
281 // same |BIO|, each call takes a reference. Use |BIO_up_ref| to balance this.
282 OPENSSL_EXPORT void SSL_set0_wbio(SSL *ssl, BIO *wbio);
283 
284 // SSL_get_rbio returns the |BIO| that |ssl| reads from.
285 OPENSSL_EXPORT BIO *SSL_get_rbio(const SSL *ssl);
286 
287 // SSL_get_wbio returns the |BIO| that |ssl| writes to.
288 OPENSSL_EXPORT BIO *SSL_get_wbio(const SSL *ssl);
289 
290 // SSL_get_fd calls |SSL_get_rfd|.
291 OPENSSL_EXPORT int SSL_get_fd(const SSL *ssl);
292 
293 // SSL_get_rfd returns the file descriptor that |ssl| is configured to read
294 // from. If |ssl|'s read |BIO| is not configured or doesn't wrap a file
295 // descriptor then it returns -1.
296 //
297 // Note: On Windows, this may return either a file descriptor or a socket (cast
298 // to int), depending on whether |ssl| was configured with a file descriptor or
299 // socket |BIO|.
300 OPENSSL_EXPORT int SSL_get_rfd(const SSL *ssl);
301 
302 // SSL_get_wfd returns the file descriptor that |ssl| is configured to write
303 // to. If |ssl|'s write |BIO| is not configured or doesn't wrap a file
304 // descriptor then it returns -1.
305 //
306 // Note: On Windows, this may return either a file descriptor or a socket (cast
307 // to int), depending on whether |ssl| was configured with a file descriptor or
308 // socket |BIO|.
309 OPENSSL_EXPORT int SSL_get_wfd(const SSL *ssl);
310 
311 // SSL_set_fd configures |ssl| to read from and write to |fd|. It returns one
312 // on success and zero on allocation error. The caller retains ownership of
313 // |fd|.
314 //
315 // On Windows, |fd| is cast to a |SOCKET| and used with Winsock APIs.
316 OPENSSL_EXPORT int SSL_set_fd(SSL *ssl, int fd);
317 
318 // SSL_set_rfd configures |ssl| to read from |fd|. It returns one on success and
319 // zero on allocation error. The caller retains ownership of |fd|.
320 //
321 // On Windows, |fd| is cast to a |SOCKET| and used with Winsock APIs.
322 OPENSSL_EXPORT int SSL_set_rfd(SSL *ssl, int fd);
323 
324 // SSL_set_wfd configures |ssl| to write to |fd|. It returns one on success and
325 // zero on allocation error. The caller retains ownership of |fd|.
326 //
327 // On Windows, |fd| is cast to a |SOCKET| and used with Winsock APIs.
328 OPENSSL_EXPORT int SSL_set_wfd(SSL *ssl, int fd);
329 
330 // SSL_do_handshake continues the current handshake. If there is none or the
331 // handshake has completed or False Started, it returns one. Otherwise, it
332 // returns <= 0. The caller should pass the value into |SSL_get_error| to
333 // determine how to proceed.
334 //
335 // In DTLS, the caller must drive retransmissions. Whenever |SSL_get_error|
336 // signals |SSL_ERROR_WANT_READ|, use |DTLSv1_get_timeout| to determine the
337 // current timeout. If it expires before the next retry, call
338 // |DTLSv1_handle_timeout|. Note that DTLS handshake retransmissions use fresh
339 // sequence numbers, so it is not sufficient to replay packets at the transport.
340 //
341 // TODO(davidben): Ensure 0 is only returned on transport EOF.
342 // https://crbug.com/466303.
343 OPENSSL_EXPORT int SSL_do_handshake(SSL *ssl);
344 
345 // SSL_connect configures |ssl| as a client, if unconfigured, and calls
346 // |SSL_do_handshake|.
347 OPENSSL_EXPORT int SSL_connect(SSL *ssl);
348 
349 // SSL_accept configures |ssl| as a server, if unconfigured, and calls
350 // |SSL_do_handshake|.
351 OPENSSL_EXPORT int SSL_accept(SSL *ssl);
352 
353 // SSL_read reads up to |num| bytes from |ssl| into |buf|. It implicitly runs
354 // any pending handshakes, including renegotiations when enabled. On success, it
355 // returns the number of bytes read. Otherwise, it returns <= 0. The caller
356 // should pass the value into |SSL_get_error| to determine how to proceed.
357 //
358 // TODO(davidben): Ensure 0 is only returned on transport EOF.
359 // https://crbug.com/466303.
360 OPENSSL_EXPORT int SSL_read(SSL *ssl, void *buf, int num);
361 
362 // SSL_peek behaves like |SSL_read| but does not consume any bytes returned.
363 OPENSSL_EXPORT int SSL_peek(SSL *ssl, void *buf, int num);
364 
365 // SSL_pending returns the number of bytes available in |ssl|. It does not read
366 // from the transport.
367 OPENSSL_EXPORT int SSL_pending(const SSL *ssl);
368 
369 // SSL_write writes up to |num| bytes from |buf| into |ssl|. It implicitly runs
370 // any pending handshakes, including renegotiations when enabled. On success, it
371 // returns the number of bytes written. Otherwise, it returns <= 0. The caller
372 // should pass the value into |SSL_get_error| to determine how to proceed.
373 //
374 // In TLS, a non-blocking |SSL_write| differs from non-blocking |write| in that
375 // a failed |SSL_write| still commits to the data passed in. When retrying, the
376 // caller must supply the original write buffer (or a larger one containing the
377 // original as a prefix). By default, retries will fail if they also do not
378 // reuse the same |buf| pointer. This may be relaxed with
379 // |SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER|, but the buffer contents still must be
380 // unchanged.
381 //
382 // By default, in TLS, |SSL_write| will not return success until all |num| bytes
383 // are written. This may be relaxed with |SSL_MODE_ENABLE_PARTIAL_WRITE|. It
384 // allows |SSL_write| to complete with a partial result when only part of the
385 // input was written in a single record.
386 //
387 // In DTLS, neither |SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER| and
388 // |SSL_MODE_ENABLE_PARTIAL_WRITE| do anything. The caller may retry with a
389 // different buffer freely. A single call to |SSL_write| only ever writes a
390 // single record in a single packet, so |num| must be at most
391 // |SSL3_RT_MAX_PLAIN_LENGTH|.
392 //
393 // TODO(davidben): Ensure 0 is only returned on transport EOF.
394 // https://crbug.com/466303.
395 OPENSSL_EXPORT int SSL_write(SSL *ssl, const void *buf, int num);
396 
397 // SSL_KEY_UPDATE_REQUESTED indicates that the peer should reply to a KeyUpdate
398 // message with its own, thus updating traffic secrets for both directions on
399 // the connection.
400 #define SSL_KEY_UPDATE_REQUESTED 1
401 
402 // SSL_KEY_UPDATE_NOT_REQUESTED indicates that the peer should not reply with
403 // it's own KeyUpdate message.
404 #define SSL_KEY_UPDATE_NOT_REQUESTED 0
405 
406 // SSL_key_update queues a TLS 1.3 KeyUpdate message to be sent on |ssl|
407 // if one is not already queued. The |request_type| argument must one of the
408 // |SSL_KEY_UPDATE_*| values. This function requires that |ssl| have completed a
409 // TLS >= 1.3 handshake. It returns one on success or zero on error.
410 //
411 // Note that this function does not _send_ the message itself. The next call to
412 // |SSL_write| will cause the message to be sent. |SSL_write| may be called with
413 // a zero length to flush a KeyUpdate message when no application data is
414 // pending.
415 OPENSSL_EXPORT int SSL_key_update(SSL *ssl, int request_type);
416 
417 // SSL_shutdown shuts down |ssl|. It runs in two stages. First, it sends
418 // close_notify and returns zero or one on success or -1 on failure. Zero
419 // indicates that close_notify was sent, but not received, and one additionally
420 // indicates that the peer's close_notify had already been received.
421 //
422 // To then wait for the peer's close_notify, run |SSL_shutdown| to completion a
423 // second time. This returns 1 on success and -1 on failure. Application data
424 // is considered a fatal error at this point. To process or discard it, read
425 // until close_notify with |SSL_read| instead.
426 //
427 // In both cases, on failure, pass the return value into |SSL_get_error| to
428 // determine how to proceed.
429 //
430 // Most callers should stop at the first stage. Reading for close_notify is
431 // primarily used for uncommon protocols where the underlying transport is
432 // reused after TLS completes. Additionally, DTLS uses an unordered transport
433 // and is unordered, so the second stage is a no-op in DTLS.
434 OPENSSL_EXPORT int SSL_shutdown(SSL *ssl);
435 
436 // SSL_CTX_set_quiet_shutdown sets quiet shutdown on |ctx| to |mode|. If
437 // enabled, |SSL_shutdown| will not send a close_notify alert or wait for one
438 // from the peer. It will instead synchronously return one.
439 OPENSSL_EXPORT void SSL_CTX_set_quiet_shutdown(SSL_CTX *ctx, int mode);
440 
441 // SSL_CTX_get_quiet_shutdown returns whether quiet shutdown is enabled for
442 // |ctx|.
443 OPENSSL_EXPORT int SSL_CTX_get_quiet_shutdown(const SSL_CTX *ctx);
444 
445 // SSL_set_quiet_shutdown sets quiet shutdown on |ssl| to |mode|. If enabled,
446 // |SSL_shutdown| will not send a close_notify alert or wait for one from the
447 // peer. It will instead synchronously return one.
448 OPENSSL_EXPORT void SSL_set_quiet_shutdown(SSL *ssl, int mode);
449 
450 // SSL_get_quiet_shutdown returns whether quiet shutdown is enabled for
451 // |ssl|.
452 OPENSSL_EXPORT int SSL_get_quiet_shutdown(const SSL *ssl);
453 
454 // SSL_get_error returns a |SSL_ERROR_*| value for the most recent operation on
455 // |ssl|. It should be called after an operation failed to determine whether the
456 // error was fatal and, if not, when to retry.
457 OPENSSL_EXPORT int SSL_get_error(const SSL *ssl, int ret_code);
458 
459 // SSL_ERROR_NONE indicates the operation succeeded.
460 #define SSL_ERROR_NONE 0
461 
462 // SSL_ERROR_SSL indicates the operation failed within the library. The caller
463 // may inspect the error queue for more information.
464 #define SSL_ERROR_SSL 1
465 
466 // SSL_ERROR_WANT_READ indicates the operation failed attempting to read from
467 // the transport. The caller may retry the operation when the transport is ready
468 // for reading.
469 //
470 // If signaled by a DTLS handshake, the caller must also call
471 // |DTLSv1_get_timeout| and |DTLSv1_handle_timeout| as appropriate. See
472 // |SSL_do_handshake|.
473 #define SSL_ERROR_WANT_READ 2
474 
475 // SSL_ERROR_WANT_WRITE indicates the operation failed attempting to write to
476 // the transport. The caller may retry the operation when the transport is ready
477 // for writing.
478 #define SSL_ERROR_WANT_WRITE 3
479 
480 // SSL_ERROR_WANT_X509_LOOKUP indicates the operation failed in calling the
481 // |cert_cb| or |client_cert_cb|. The caller may retry the operation when the
482 // callback is ready to return a certificate or one has been configured
483 // externally.
484 //
485 // See also |SSL_CTX_set_cert_cb| and |SSL_CTX_set_client_cert_cb|.
486 #define SSL_ERROR_WANT_X509_LOOKUP 4
487 
488 // SSL_ERROR_SYSCALL indicates the operation failed externally to the library.
489 // The caller should consult the system-specific error mechanism. This is
490 // typically |errno| but may be something custom if using a custom |BIO|. It
491 // may also be signaled if the transport returned EOF, in which case the
492 // operation's return value will be zero.
493 #define SSL_ERROR_SYSCALL 5
494 
495 // SSL_ERROR_ZERO_RETURN indicates the operation failed because the connection
496 // was cleanly shut down with a close_notify alert.
497 #define SSL_ERROR_ZERO_RETURN 6
498 
499 // SSL_ERROR_WANT_CONNECT indicates the operation failed attempting to connect
500 // the transport (the |BIO| signaled |BIO_RR_CONNECT|). The caller may retry the
501 // operation when the transport is ready.
502 #define SSL_ERROR_WANT_CONNECT 7
503 
504 // SSL_ERROR_WANT_ACCEPT indicates the operation failed attempting to accept a
505 // connection from the transport (the |BIO| signaled |BIO_RR_ACCEPT|). The
506 // caller may retry the operation when the transport is ready.
507 //
508 // TODO(davidben): Remove this. It's used by accept BIOs which are bizarre.
509 #define SSL_ERROR_WANT_ACCEPT 8
510 
511 // SSL_ERROR_WANT_CHANNEL_ID_LOOKUP is never used.
512 //
513 // TODO(davidben): Remove this. Some callers reference it when stringifying
514 // errors. They should use |SSL_error_description| instead.
515 #define SSL_ERROR_WANT_CHANNEL_ID_LOOKUP 9
516 
517 // SSL_ERROR_PENDING_SESSION indicates the operation failed because the session
518 // lookup callback indicated the session was unavailable. The caller may retry
519 // the operation when lookup has completed.
520 //
521 // See also |SSL_CTX_sess_set_get_cb| and |SSL_magic_pending_session_ptr|.
522 #define SSL_ERROR_PENDING_SESSION 11
523 
524 // SSL_ERROR_PENDING_CERTIFICATE indicates the operation failed because the
525 // early callback indicated certificate lookup was incomplete. The caller may
526 // retry the operation when lookup has completed.
527 //
528 // See also |SSL_CTX_set_select_certificate_cb|.
529 #define SSL_ERROR_PENDING_CERTIFICATE 12
530 
531 // SSL_ERROR_WANT_PRIVATE_KEY_OPERATION indicates the operation failed because
532 // a private key operation was unfinished. The caller may retry the operation
533 // when the private key operation is complete.
534 //
535 // See also |SSL_set_private_key_method| and
536 // |SSL_CTX_set_private_key_method|.
537 #define SSL_ERROR_WANT_PRIVATE_KEY_OPERATION 13
538 
539 // SSL_ERROR_PENDING_TICKET indicates that a ticket decryption is pending. The
540 // caller may retry the operation when the decryption is ready.
541 //
542 // See also |SSL_CTX_set_ticket_aead_method|.
543 #define SSL_ERROR_PENDING_TICKET 14
544 
545 // SSL_ERROR_EARLY_DATA_REJECTED indicates that early data was rejected. The
546 // caller should treat this as a connection failure and retry any operations
547 // associated with the rejected early data. |SSL_reset_early_data_reject| may be
548 // used to reuse the underlying connection for the retry.
549 #define SSL_ERROR_EARLY_DATA_REJECTED 15
550 
551 // SSL_ERROR_WANT_CERTIFICATE_VERIFY indicates the operation failed because
552 // certificate verification was incomplete. The caller may retry the operation
553 // when certificate verification is complete.
554 //
555 // See also |SSL_CTX_set_custom_verify|.
556 #define SSL_ERROR_WANT_CERTIFICATE_VERIFY 16
557 
558 #define SSL_ERROR_HANDOFF 17
559 #define SSL_ERROR_HANDBACK 18
560 
561 // SSL_ERROR_WANT_RENEGOTIATE indicates the operation is pending a response to
562 // a renegotiation request from the server. The caller may call
563 // |SSL_renegotiate| to schedule a renegotiation and retry the operation.
564 //
565 // See also |ssl_renegotiate_explicit|.
566 #define SSL_ERROR_WANT_RENEGOTIATE 19
567 
568 // SSL_ERROR_HANDSHAKE_HINTS_READY indicates the handshake has progressed enough
569 // for |SSL_serialize_handshake_hints| to be called. See also
570 // |SSL_request_handshake_hints|.
571 #define SSL_ERROR_HANDSHAKE_HINTS_READY 20
572 
573 // SSL_error_description returns a string representation of |err|, where |err|
574 // is one of the |SSL_ERROR_*| constants returned by |SSL_get_error|, or NULL
575 // if the value is unrecognized.
576 OPENSSL_EXPORT const char *SSL_error_description(int err);
577 
578 // SSL_set_mtu sets the |ssl|'s MTU in DTLS to |mtu|. It returns one on success
579 // and zero on failure.
580 OPENSSL_EXPORT int SSL_set_mtu(SSL *ssl, unsigned mtu);
581 
582 // DTLSv1_set_initial_timeout_duration sets the initial duration for a DTLS
583 // handshake timeout.
584 //
585 // This duration overrides the default of 1 second, which is the strong
586 // recommendation of RFC 6347 (see section 4.2.4.1). However, there may exist
587 // situations where a shorter timeout would be beneficial, such as for
588 // time-sensitive applications.
589 OPENSSL_EXPORT void DTLSv1_set_initial_timeout_duration(SSL *ssl,
590                                                         unsigned duration_ms);
591 
592 // DTLSv1_get_timeout queries the next DTLS handshake timeout. If there is a
593 // timeout in progress, it sets |*out| to the time remaining and returns one.
594 // Otherwise, it returns zero.
595 //
596 // When the timeout expires, call |DTLSv1_handle_timeout| to handle the
597 // retransmit behavior.
598 //
599 // NOTE: This function must be queried again whenever the handshake state
600 // machine changes, including when |DTLSv1_handle_timeout| is called.
601 OPENSSL_EXPORT int DTLSv1_get_timeout(const SSL *ssl, struct timeval *out);
602 
603 // DTLSv1_handle_timeout is called when a DTLS handshake timeout expires. If no
604 // timeout had expired, it returns 0. Otherwise, it retransmits the previous
605 // flight of handshake messages and returns 1. If too many timeouts had expired
606 // without progress or an error occurs, it returns -1.
607 //
608 // The caller's external timer should be compatible with the one |ssl| queries
609 // within some fudge factor. Otherwise, the call will be a no-op, but
610 // |DTLSv1_get_timeout| will return an updated timeout.
611 //
612 // If the function returns -1, checking if |SSL_get_error| returns
613 // |SSL_ERROR_WANT_WRITE| may be used to determine if the retransmit failed due
614 // to a non-fatal error at the write |BIO|. However, the operation may not be
615 // retried until the next timeout fires.
616 //
617 // WARNING: This function breaks the usual return value convention.
618 //
619 // TODO(davidben): This |SSL_ERROR_WANT_WRITE| behavior is kind of bizarre.
620 OPENSSL_EXPORT int DTLSv1_handle_timeout(SSL *ssl);
621 
622 
623 // Protocol versions.
624 
625 #define DTLS1_VERSION_MAJOR 0xfe
626 #define SSL3_VERSION_MAJOR 0x03
627 
628 #define SSL3_VERSION 0x0300
629 #define TLS1_VERSION 0x0301
630 #define TLS1_1_VERSION 0x0302
631 #define TLS1_2_VERSION 0x0303
632 #define TLS1_3_VERSION 0x0304
633 
634 #define DTLS1_VERSION 0xfeff
635 #define DTLS1_2_VERSION 0xfefd
636 
637 // SSL_CTX_set_min_proto_version sets the minimum protocol version for |ctx| to
638 // |version|. If |version| is zero, the default minimum version is used. It
639 // returns one on success and zero if |version| is invalid.
640 OPENSSL_EXPORT int SSL_CTX_set_min_proto_version(SSL_CTX *ctx,
641                                                  uint16_t version);
642 
643 // SSL_CTX_set_max_proto_version sets the maximum protocol version for |ctx| to
644 // |version|. If |version| is zero, the default maximum version is used. It
645 // returns one on success and zero if |version| is invalid.
646 OPENSSL_EXPORT int SSL_CTX_set_max_proto_version(SSL_CTX *ctx,
647                                                  uint16_t version);
648 
649 // SSL_CTX_get_min_proto_version returns the minimum protocol version for |ctx|
650 OPENSSL_EXPORT uint16_t SSL_CTX_get_min_proto_version(const SSL_CTX *ctx);
651 
652 // SSL_CTX_get_max_proto_version returns the maximum protocol version for |ctx|
653 OPENSSL_EXPORT uint16_t SSL_CTX_get_max_proto_version(const SSL_CTX *ctx);
654 
655 // SSL_set_min_proto_version sets the minimum protocol version for |ssl| to
656 // |version|. If |version| is zero, the default minimum version is used. It
657 // returns one on success and zero if |version| is invalid.
658 OPENSSL_EXPORT int SSL_set_min_proto_version(SSL *ssl, uint16_t version);
659 
660 // SSL_set_max_proto_version sets the maximum protocol version for |ssl| to
661 // |version|. If |version| is zero, the default maximum version is used. It
662 // returns one on success and zero if |version| is invalid.
663 OPENSSL_EXPORT int SSL_set_max_proto_version(SSL *ssl, uint16_t version);
664 
665 // SSL_get_min_proto_version returns the minimum protocol version for |ssl|. If
666 // the connection's configuration has been shed, 0 is returned.
667 OPENSSL_EXPORT uint16_t SSL_get_min_proto_version(const SSL *ssl);
668 
669 // SSL_get_max_proto_version returns the maximum protocol version for |ssl|. If
670 // the connection's configuration has been shed, 0 is returned.
671 OPENSSL_EXPORT uint16_t SSL_get_max_proto_version(const SSL *ssl);
672 
673 // SSL_version returns the TLS or DTLS protocol version used by |ssl|, which is
674 // one of the |*_VERSION| values. (E.g. |TLS1_2_VERSION|.) Before the version
675 // is negotiated, the result is undefined.
676 OPENSSL_EXPORT int SSL_version(const SSL *ssl);
677 
678 
679 // Options.
680 //
681 // Options configure protocol behavior.
682 
683 // SSL_OP_NO_QUERY_MTU, in DTLS, disables querying the MTU from the underlying
684 // |BIO|. Instead, the MTU is configured with |SSL_set_mtu|.
685 #define SSL_OP_NO_QUERY_MTU 0x00001000L
686 
687 // SSL_OP_NO_TICKET disables session ticket support (RFC 5077).
688 #define SSL_OP_NO_TICKET 0x00004000L
689 
690 // SSL_OP_CIPHER_SERVER_PREFERENCE configures servers to select ciphers and
691 // ECDHE curves according to the server's preferences instead of the
692 // client's.
693 #define SSL_OP_CIPHER_SERVER_PREFERENCE 0x00400000L
694 
695 // The following flags toggle individual protocol versions. This is deprecated.
696 // Use |SSL_CTX_set_min_proto_version| and |SSL_CTX_set_max_proto_version|
697 // instead.
698 #define SSL_OP_NO_TLSv1 0x04000000L
699 #define SSL_OP_NO_TLSv1_2 0x08000000L
700 #define SSL_OP_NO_TLSv1_1 0x10000000L
701 #define SSL_OP_NO_TLSv1_3 0x20000000L
702 #define SSL_OP_NO_DTLSv1 SSL_OP_NO_TLSv1
703 #define SSL_OP_NO_DTLSv1_2 SSL_OP_NO_TLSv1_2
704 
705 // SSL_CTX_set_options enables all options set in |options| (which should be one
706 // or more of the |SSL_OP_*| values, ORed together) in |ctx|. It returns a
707 // bitmask representing the resulting enabled options.
708 OPENSSL_EXPORT uint32_t SSL_CTX_set_options(SSL_CTX *ctx, uint32_t options);
709 
710 // SSL_CTX_clear_options disables all options set in |options| (which should be
711 // one or more of the |SSL_OP_*| values, ORed together) in |ctx|. It returns a
712 // bitmask representing the resulting enabled options.
713 OPENSSL_EXPORT uint32_t SSL_CTX_clear_options(SSL_CTX *ctx, uint32_t options);
714 
715 // SSL_CTX_get_options returns a bitmask of |SSL_OP_*| values that represent all
716 // the options enabled for |ctx|.
717 OPENSSL_EXPORT uint32_t SSL_CTX_get_options(const SSL_CTX *ctx);
718 
719 // SSL_set_options enables all options set in |options| (which should be one or
720 // more of the |SSL_OP_*| values, ORed together) in |ssl|. It returns a bitmask
721 // representing the resulting enabled options.
722 OPENSSL_EXPORT uint32_t SSL_set_options(SSL *ssl, uint32_t options);
723 
724 // SSL_clear_options disables all options set in |options| (which should be one
725 // or more of the |SSL_OP_*| values, ORed together) in |ssl|. It returns a
726 // bitmask representing the resulting enabled options.
727 OPENSSL_EXPORT uint32_t SSL_clear_options(SSL *ssl, uint32_t options);
728 
729 // SSL_get_options returns a bitmask of |SSL_OP_*| values that represent all the
730 // options enabled for |ssl|.
731 OPENSSL_EXPORT uint32_t SSL_get_options(const SSL *ssl);
732 
733 
734 // Modes.
735 //
736 // Modes configure API behavior.
737 
738 // SSL_MODE_ENABLE_PARTIAL_WRITE, in TLS, allows |SSL_write| to complete with a
739 // partial result when the only part of the input was written in a single
740 // record. In DTLS, it does nothing.
741 #define SSL_MODE_ENABLE_PARTIAL_WRITE 0x00000001L
742 
743 // SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER, in TLS, allows retrying an incomplete
744 // |SSL_write| with a different buffer. However, |SSL_write| still assumes the
745 // buffer contents are unchanged. This is not the default to avoid the
746 // misconception that non-blocking |SSL_write| behaves like non-blocking
747 // |write|. In DTLS, it does nothing.
748 #define SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER 0x00000002L
749 
750 // SSL_MODE_NO_AUTO_CHAIN disables automatically building a certificate chain
751 // before sending certificates to the peer. This flag is set (and the feature
752 // disabled) by default.
753 // TODO(davidben): Remove this behavior. https://crbug.com/boringssl/42.
754 #define SSL_MODE_NO_AUTO_CHAIN 0x00000008L
755 
756 // SSL_MODE_ENABLE_FALSE_START allows clients to send application data before
757 // receipt of ChangeCipherSpec and Finished. This mode enables full handshakes
758 // to 'complete' in one RTT. See RFC 7918.
759 //
760 // When False Start is enabled, |SSL_do_handshake| may succeed before the
761 // handshake has completely finished. |SSL_write| will function at this point,
762 // and |SSL_read| will transparently wait for the final handshake leg before
763 // returning application data. To determine if False Start occurred or when the
764 // handshake is completely finished, see |SSL_in_false_start|, |SSL_in_init|,
765 // and |SSL_CB_HANDSHAKE_DONE| from |SSL_CTX_set_info_callback|.
766 #define SSL_MODE_ENABLE_FALSE_START 0x00000080L
767 
768 // SSL_MODE_CBC_RECORD_SPLITTING causes multi-byte CBC records in TLS 1.0 to be
769 // split in two: the first record will contain a single byte and the second will
770 // contain the remainder. This effectively randomises the IV and prevents BEAST
771 // attacks.
772 #define SSL_MODE_CBC_RECORD_SPLITTING 0x00000100L
773 
774 // SSL_MODE_NO_SESSION_CREATION will cause any attempts to create a session to
775 // fail with SSL_R_SESSION_MAY_NOT_BE_CREATED. This can be used to enforce that
776 // session resumption is used for a given SSL*.
777 #define SSL_MODE_NO_SESSION_CREATION 0x00000200L
778 
779 // SSL_MODE_SEND_FALLBACK_SCSV sends TLS_FALLBACK_SCSV in the ClientHello.
780 // To be set only by applications that reconnect with a downgraded protocol
781 // version; see RFC 7507 for details.
782 //
783 // DO NOT ENABLE THIS if your application attempts a normal handshake. Only use
784 // this in explicit fallback retries, following the guidance in RFC 7507.
785 #define SSL_MODE_SEND_FALLBACK_SCSV 0x00000400L
786 
787 // SSL_CTX_set_mode enables all modes set in |mode| (which should be one or more
788 // of the |SSL_MODE_*| values, ORed together) in |ctx|. It returns a bitmask
789 // representing the resulting enabled modes.
790 OPENSSL_EXPORT uint32_t SSL_CTX_set_mode(SSL_CTX *ctx, uint32_t mode);
791 
792 // SSL_CTX_clear_mode disables all modes set in |mode| (which should be one or
793 // more of the |SSL_MODE_*| values, ORed together) in |ctx|. It returns a
794 // bitmask representing the resulting enabled modes.
795 OPENSSL_EXPORT uint32_t SSL_CTX_clear_mode(SSL_CTX *ctx, uint32_t mode);
796 
797 // SSL_CTX_get_mode returns a bitmask of |SSL_MODE_*| values that represent all
798 // the modes enabled for |ssl|.
799 OPENSSL_EXPORT uint32_t SSL_CTX_get_mode(const SSL_CTX *ctx);
800 
801 // SSL_set_mode enables all modes set in |mode| (which should be one or more of
802 // the |SSL_MODE_*| values, ORed together) in |ssl|. It returns a bitmask
803 // representing the resulting enabled modes.
804 OPENSSL_EXPORT uint32_t SSL_set_mode(SSL *ssl, uint32_t mode);
805 
806 // SSL_clear_mode disables all modes set in |mode| (which should be one or more
807 // of the |SSL_MODE_*| values, ORed together) in |ssl|. It returns a bitmask
808 // representing the resulting enabled modes.
809 OPENSSL_EXPORT uint32_t SSL_clear_mode(SSL *ssl, uint32_t mode);
810 
811 // SSL_get_mode returns a bitmask of |SSL_MODE_*| values that represent all the
812 // modes enabled for |ssl|.
813 OPENSSL_EXPORT uint32_t SSL_get_mode(const SSL *ssl);
814 
815 // SSL_CTX_set0_buffer_pool sets a |CRYPTO_BUFFER_POOL| that will be used to
816 // store certificates. This can allow multiple connections to share
817 // certificates and thus save memory.
818 //
819 // The SSL_CTX does not take ownership of |pool| and the caller must ensure
820 // that |pool| outlives |ctx| and all objects linked to it, including |SSL|,
821 // |X509| and |SSL_SESSION| objects. Basically, don't ever free |pool|.
822 OPENSSL_EXPORT void SSL_CTX_set0_buffer_pool(SSL_CTX *ctx,
823                                              CRYPTO_BUFFER_POOL *pool);
824 
825 
826 // Configuring certificates and private keys.
827 //
828 // These functions configure the connection's leaf certificate, private key, and
829 // certificate chain. The certificate chain is ordered leaf to root (as sent on
830 // the wire) but does not include the leaf. Both client and server certificates
831 // use these functions.
832 //
833 // Certificates and keys may be configured before the handshake or dynamically
834 // in the early callback and certificate callback.
835 
836 // SSL_CTX_use_certificate sets |ctx|'s leaf certificate to |x509|. It returns
837 // one on success and zero on failure.
838 OPENSSL_EXPORT int SSL_CTX_use_certificate(SSL_CTX *ctx, X509 *x509);
839 
840 // SSL_use_certificate sets |ssl|'s leaf certificate to |x509|. It returns one
841 // on success and zero on failure.
842 OPENSSL_EXPORT int SSL_use_certificate(SSL *ssl, X509 *x509);
843 
844 // SSL_CTX_use_PrivateKey sets |ctx|'s private key to |pkey|. It returns one on
845 // success and zero on failure.
846 OPENSSL_EXPORT int SSL_CTX_use_PrivateKey(SSL_CTX *ctx, EVP_PKEY *pkey);
847 
848 // SSL_use_PrivateKey sets |ssl|'s private key to |pkey|. It returns one on
849 // success and zero on failure.
850 OPENSSL_EXPORT int SSL_use_PrivateKey(SSL *ssl, EVP_PKEY *pkey);
851 
852 // SSL_CTX_set0_chain sets |ctx|'s certificate chain, excluding the leaf, to
853 // |chain|. On success, it returns one and takes ownership of |chain|.
854 // Otherwise, it returns zero.
855 OPENSSL_EXPORT int SSL_CTX_set0_chain(SSL_CTX *ctx, STACK_OF(X509) *chain);
856 
857 // SSL_CTX_set1_chain sets |ctx|'s certificate chain, excluding the leaf, to
858 // |chain|. It returns one on success and zero on failure. The caller retains
859 // ownership of |chain| and may release it freely.
860 OPENSSL_EXPORT int SSL_CTX_set1_chain(SSL_CTX *ctx, STACK_OF(X509) *chain);
861 
862 // SSL_set0_chain sets |ssl|'s certificate chain, excluding the leaf, to
863 // |chain|. On success, it returns one and takes ownership of |chain|.
864 // Otherwise, it returns zero.
865 OPENSSL_EXPORT int SSL_set0_chain(SSL *ssl, STACK_OF(X509) *chain);
866 
867 // SSL_set1_chain sets |ssl|'s certificate chain, excluding the leaf, to
868 // |chain|. It returns one on success and zero on failure. The caller retains
869 // ownership of |chain| and may release it freely.
870 OPENSSL_EXPORT int SSL_set1_chain(SSL *ssl, STACK_OF(X509) *chain);
871 
872 // SSL_CTX_add0_chain_cert appends |x509| to |ctx|'s certificate chain. On
873 // success, it returns one and takes ownership of |x509|. Otherwise, it returns
874 // zero.
875 OPENSSL_EXPORT int SSL_CTX_add0_chain_cert(SSL_CTX *ctx, X509 *x509);
876 
877 // SSL_CTX_add1_chain_cert appends |x509| to |ctx|'s certificate chain. It
878 // returns one on success and zero on failure. The caller retains ownership of
879 // |x509| and may release it freely.
880 OPENSSL_EXPORT int SSL_CTX_add1_chain_cert(SSL_CTX *ctx, X509 *x509);
881 
882 // SSL_add0_chain_cert appends |x509| to |ctx|'s certificate chain. On success,
883 // it returns one and takes ownership of |x509|. Otherwise, it returns zero.
884 OPENSSL_EXPORT int SSL_add0_chain_cert(SSL *ssl, X509 *x509);
885 
886 // SSL_CTX_add_extra_chain_cert calls |SSL_CTX_add0_chain_cert|.
887 OPENSSL_EXPORT int SSL_CTX_add_extra_chain_cert(SSL_CTX *ctx, X509 *x509);
888 
889 // SSL_add1_chain_cert appends |x509| to |ctx|'s certificate chain. It returns
890 // one on success and zero on failure. The caller retains ownership of |x509|
891 // and may release it freely.
892 OPENSSL_EXPORT int SSL_add1_chain_cert(SSL *ssl, X509 *x509);
893 
894 // SSL_CTX_clear_chain_certs clears |ctx|'s certificate chain and returns
895 // one.
896 OPENSSL_EXPORT int SSL_CTX_clear_chain_certs(SSL_CTX *ctx);
897 
898 // SSL_CTX_clear_extra_chain_certs calls |SSL_CTX_clear_chain_certs|.
899 OPENSSL_EXPORT int SSL_CTX_clear_extra_chain_certs(SSL_CTX *ctx);
900 
901 // SSL_clear_chain_certs clears |ssl|'s certificate chain and returns one.
902 OPENSSL_EXPORT int SSL_clear_chain_certs(SSL *ssl);
903 
904 // SSL_CTX_set_cert_cb sets a callback that is called to select a certificate.
905 // The callback returns one on success, zero on internal error, and a negative
906 // number on failure or to pause the handshake. If the handshake is paused,
907 // |SSL_get_error| will return |SSL_ERROR_WANT_X509_LOOKUP|.
908 //
909 // On the client, the callback may call |SSL_get0_certificate_types| and
910 // |SSL_get_client_CA_list| for information on the server's certificate
911 // request.
912 //
913 // On the server, the callback will be called after extensions have been
914 // processed, but before the resumption decision has been made. This differs
915 // from OpenSSL which handles resumption before selecting the certificate.
916 OPENSSL_EXPORT void SSL_CTX_set_cert_cb(SSL_CTX *ctx,
917                                         int (*cb)(SSL *ssl, void *arg),
918                                         void *arg);
919 
920 // SSL_set_cert_cb sets a callback that is called to select a certificate. The
921 // callback returns one on success, zero on internal error, and a negative
922 // number on failure or to pause the handshake. If the handshake is paused,
923 // |SSL_get_error| will return |SSL_ERROR_WANT_X509_LOOKUP|.
924 //
925 // On the client, the callback may call |SSL_get0_certificate_types| and
926 // |SSL_get_client_CA_list| for information on the server's certificate
927 // request.
928 //
929 // On the server, the callback will be called after extensions have been
930 // processed, but before the resumption decision has been made. This differs
931 // from OpenSSL which handles resumption before selecting the certificate.
932 OPENSSL_EXPORT void SSL_set_cert_cb(SSL *ssl, int (*cb)(SSL *ssl, void *arg),
933                                     void *arg);
934 
935 // SSL_get0_certificate_types, for a client, sets |*out_types| to an array
936 // containing the client certificate types requested by a server. It returns the
937 // length of the array. Note this list is always empty in TLS 1.3. The server
938 // will instead send signature algorithms. See
939 // |SSL_get0_peer_verify_algorithms|.
940 //
941 // The behavior of this function is undefined except during the callbacks set by
942 // by |SSL_CTX_set_cert_cb| and |SSL_CTX_set_client_cert_cb| or when the
943 // handshake is paused because of them.
944 OPENSSL_EXPORT size_t SSL_get0_certificate_types(const SSL *ssl,
945                                                  const uint8_t **out_types);
946 
947 // SSL_get0_peer_verify_algorithms sets |*out_sigalgs| to an array containing
948 // the signature algorithms the peer is able to verify. It returns the length of
949 // the array. Note these values are only sent starting TLS 1.2 and only
950 // mandatory starting TLS 1.3. If not sent, the empty array is returned. For the
951 // historical client certificate types list, see |SSL_get0_certificate_types|.
952 //
953 // The behavior of this function is undefined except during the callbacks set by
954 // by |SSL_CTX_set_cert_cb| and |SSL_CTX_set_client_cert_cb| or when the
955 // handshake is paused because of them.
956 OPENSSL_EXPORT size_t
957 SSL_get0_peer_verify_algorithms(const SSL *ssl, const uint16_t **out_sigalgs);
958 
959 // SSL_get0_peer_delegation_algorithms sets |*out_sigalgs| to an array
960 // containing the signature algorithms the peer is willing to use with delegated
961 // credentials.  It returns the length of the array. If not sent, the empty
962 // array is returned.
963 //
964 // The behavior of this function is undefined except during the callbacks set by
965 // by |SSL_CTX_set_cert_cb| and |SSL_CTX_set_client_cert_cb| or when the
966 // handshake is paused because of them.
967 OPENSSL_EXPORT size_t
968 SSL_get0_peer_delegation_algorithms(const SSL *ssl,
969                                     const uint16_t **out_sigalgs);
970 
971 // SSL_certs_clear resets the private key, leaf certificate, and certificate
972 // chain of |ssl|.
973 OPENSSL_EXPORT void SSL_certs_clear(SSL *ssl);
974 
975 // SSL_CTX_check_private_key returns one if the certificate and private key
976 // configured in |ctx| are consistent and zero otherwise.
977 OPENSSL_EXPORT int SSL_CTX_check_private_key(const SSL_CTX *ctx);
978 
979 // SSL_check_private_key returns one if the certificate and private key
980 // configured in |ssl| are consistent and zero otherwise.
981 OPENSSL_EXPORT int SSL_check_private_key(const SSL *ssl);
982 
983 // SSL_CTX_get0_certificate returns |ctx|'s leaf certificate.
984 OPENSSL_EXPORT X509 *SSL_CTX_get0_certificate(const SSL_CTX *ctx);
985 
986 // SSL_get_certificate returns |ssl|'s leaf certificate.
987 OPENSSL_EXPORT X509 *SSL_get_certificate(const SSL *ssl);
988 
989 // SSL_CTX_get0_privatekey returns |ctx|'s private key.
990 OPENSSL_EXPORT EVP_PKEY *SSL_CTX_get0_privatekey(const SSL_CTX *ctx);
991 
992 // SSL_get_privatekey returns |ssl|'s private key.
993 OPENSSL_EXPORT EVP_PKEY *SSL_get_privatekey(const SSL *ssl);
994 
995 // SSL_CTX_get0_chain_certs sets |*out_chain| to |ctx|'s certificate chain and
996 // returns one.
997 OPENSSL_EXPORT int SSL_CTX_get0_chain_certs(const SSL_CTX *ctx,
998                                             STACK_OF(X509) **out_chain);
999 
1000 // SSL_CTX_get_extra_chain_certs calls |SSL_CTX_get0_chain_certs|.
1001 OPENSSL_EXPORT int SSL_CTX_get_extra_chain_certs(const SSL_CTX *ctx,
1002                                                  STACK_OF(X509) **out_chain);
1003 
1004 // SSL_get0_chain_certs sets |*out_chain| to |ssl|'s certificate chain and
1005 // returns one.
1006 OPENSSL_EXPORT int SSL_get0_chain_certs(const SSL *ssl,
1007                                         STACK_OF(X509) **out_chain);
1008 
1009 // SSL_CTX_set_signed_cert_timestamp_list sets the list of signed certificate
1010 // timestamps that is sent to clients that request it. The |list| argument must
1011 // contain one or more SCT structures serialised as a SignedCertificateTimestamp
1012 // List (see https://tools.ietf.org/html/rfc6962#section-3.3) – i.e. each SCT
1013 // is prefixed by a big-endian, uint16 length and the concatenation of one or
1014 // more such prefixed SCTs are themselves also prefixed by a uint16 length. It
1015 // returns one on success and zero on error. The caller retains ownership of
1016 // |list|.
1017 OPENSSL_EXPORT int SSL_CTX_set_signed_cert_timestamp_list(SSL_CTX *ctx,
1018                                                           const uint8_t *list,
1019                                                           size_t list_len);
1020 
1021 // SSL_set_signed_cert_timestamp_list sets the list of signed certificate
1022 // timestamps that is sent to clients that request is. The same format as the
1023 // one used for |SSL_CTX_set_signed_cert_timestamp_list| applies. The caller
1024 // retains ownership of |list|.
1025 OPENSSL_EXPORT int SSL_set_signed_cert_timestamp_list(SSL *ctx,
1026                                                       const uint8_t *list,
1027                                                       size_t list_len);
1028 
1029 // SSL_CTX_set_ocsp_response sets the OCSP response that is sent to clients
1030 // which request it. It returns one on success and zero on error. The caller
1031 // retains ownership of |response|.
1032 OPENSSL_EXPORT int SSL_CTX_set_ocsp_response(SSL_CTX *ctx,
1033                                              const uint8_t *response,
1034                                              size_t response_len);
1035 
1036 // SSL_set_ocsp_response sets the OCSP response that is sent to clients which
1037 // request it. It returns one on success and zero on error. The caller retains
1038 // ownership of |response|.
1039 OPENSSL_EXPORT int SSL_set_ocsp_response(SSL *ssl,
1040                                          const uint8_t *response,
1041                                          size_t response_len);
1042 
1043 // SSL_SIGN_* are signature algorithm values as defined in TLS 1.3.
1044 #define SSL_SIGN_RSA_PKCS1_SHA1 0x0201
1045 #define SSL_SIGN_RSA_PKCS1_SHA256 0x0401
1046 #define SSL_SIGN_RSA_PKCS1_SHA384 0x0501
1047 #define SSL_SIGN_RSA_PKCS1_SHA512 0x0601
1048 #define SSL_SIGN_ECDSA_SHA1 0x0203
1049 #define SSL_SIGN_ECDSA_SECP256R1_SHA256 0x0403
1050 #define SSL_SIGN_ECDSA_SECP384R1_SHA384 0x0503
1051 #define SSL_SIGN_ECDSA_SECP521R1_SHA512 0x0603
1052 #define SSL_SIGN_RSA_PSS_RSAE_SHA256 0x0804
1053 #define SSL_SIGN_RSA_PSS_RSAE_SHA384 0x0805
1054 #define SSL_SIGN_RSA_PSS_RSAE_SHA512 0x0806
1055 #define SSL_SIGN_ED25519 0x0807
1056 
1057 // SSL_SIGN_RSA_PKCS1_MD5_SHA1 is an internal signature algorithm used to
1058 // specify raw RSASSA-PKCS1-v1_5 with an MD5/SHA-1 concatenation, as used in TLS
1059 // before TLS 1.2.
1060 #define SSL_SIGN_RSA_PKCS1_MD5_SHA1 0xff01
1061 
1062 // SSL_get_signature_algorithm_name returns a human-readable name for |sigalg|,
1063 // or NULL if unknown. If |include_curve| is one, the curve for ECDSA algorithms
1064 // is included as in TLS 1.3. Otherwise, it is excluded as in TLS 1.2.
1065 OPENSSL_EXPORT const char *SSL_get_signature_algorithm_name(uint16_t sigalg,
1066                                                             int include_curve);
1067 
1068 // SSL_get_signature_algorithm_key_type returns the key type associated with
1069 // |sigalg| as an |EVP_PKEY_*| constant or |EVP_PKEY_NONE| if unknown.
1070 OPENSSL_EXPORT int SSL_get_signature_algorithm_key_type(uint16_t sigalg);
1071 
1072 // SSL_get_signature_algorithm_digest returns the digest function associated
1073 // with |sigalg| or |NULL| if |sigalg| has no prehash (Ed25519) or is unknown.
1074 OPENSSL_EXPORT const EVP_MD *SSL_get_signature_algorithm_digest(
1075     uint16_t sigalg);
1076 
1077 // SSL_is_signature_algorithm_rsa_pss returns one if |sigalg| is an RSA-PSS
1078 // signature algorithm and zero otherwise.
1079 OPENSSL_EXPORT int SSL_is_signature_algorithm_rsa_pss(uint16_t sigalg);
1080 
1081 // SSL_CTX_set_signing_algorithm_prefs configures |ctx| to use |prefs| as the
1082 // preference list when signing with |ctx|'s private key. It returns one on
1083 // success and zero on error. |prefs| should not include the internal-only value
1084 // |SSL_SIGN_RSA_PKCS1_MD5_SHA1|.
1085 OPENSSL_EXPORT int SSL_CTX_set_signing_algorithm_prefs(SSL_CTX *ctx,
1086                                                        const uint16_t *prefs,
1087                                                        size_t num_prefs);
1088 
1089 // SSL_set_signing_algorithm_prefs configures |ssl| to use |prefs| as the
1090 // preference list when signing with |ssl|'s private key. It returns one on
1091 // success and zero on error. |prefs| should not include the internal-only value
1092 // |SSL_SIGN_RSA_PKCS1_MD5_SHA1|.
1093 OPENSSL_EXPORT int SSL_set_signing_algorithm_prefs(SSL *ssl,
1094                                                    const uint16_t *prefs,
1095                                                    size_t num_prefs);
1096 
1097 
1098 // Certificate and private key convenience functions.
1099 
1100 // SSL_CTX_set_chain_and_key sets the certificate chain and private key for a
1101 // TLS client or server. References to the given |CRYPTO_BUFFER| and |EVP_PKEY|
1102 // objects are added as needed. Exactly one of |privkey| or |privkey_method|
1103 // may be non-NULL. Returns one on success and zero on error.
1104 OPENSSL_EXPORT int SSL_CTX_set_chain_and_key(
1105     SSL_CTX *ctx, CRYPTO_BUFFER *const *certs, size_t num_certs,
1106     EVP_PKEY *privkey, const SSL_PRIVATE_KEY_METHOD *privkey_method);
1107 
1108 // SSL_set_chain_and_key sets the certificate chain and private key for a TLS
1109 // client or server. References to the given |CRYPTO_BUFFER| and |EVP_PKEY|
1110 // objects are added as needed. Exactly one of |privkey| or |privkey_method|
1111 // may be non-NULL. Returns one on success and zero on error.
1112 OPENSSL_EXPORT int SSL_set_chain_and_key(
1113     SSL *ssl, CRYPTO_BUFFER *const *certs, size_t num_certs, EVP_PKEY *privkey,
1114     const SSL_PRIVATE_KEY_METHOD *privkey_method);
1115 
1116 // SSL_CTX_get0_chain returns the list of |CRYPTO_BUFFER|s that were set by
1117 // |SSL_CTX_set_chain_and_key|. Reference counts are not incremented by this
1118 // call. The return value may be |NULL| if no chain has been set.
1119 //
1120 // (Note: if a chain was configured by non-|CRYPTO_BUFFER|-based functions then
1121 // the return value is undefined and, even if not NULL, the stack itself may
1122 // contain nullptrs. Thus you shouldn't mix this function with
1123 // non-|CRYPTO_BUFFER| functions for manipulating the chain.)
1124 //
1125 // There is no |SSL*| version of this function because connections discard
1126 // configuration after handshaking, thus making it of questionable utility.
1127 OPENSSL_EXPORT const STACK_OF(CRYPTO_BUFFER)*
1128     SSL_CTX_get0_chain(const SSL_CTX *ctx);
1129 
1130 // SSL_CTX_use_RSAPrivateKey sets |ctx|'s private key to |rsa|. It returns one
1131 // on success and zero on failure.
1132 OPENSSL_EXPORT int SSL_CTX_use_RSAPrivateKey(SSL_CTX *ctx, RSA *rsa);
1133 
1134 // SSL_use_RSAPrivateKey sets |ctx|'s private key to |rsa|. It returns one on
1135 // success and zero on failure.
1136 OPENSSL_EXPORT int SSL_use_RSAPrivateKey(SSL *ssl, RSA *rsa);
1137 
1138 // The following functions configure certificates or private keys but take as
1139 // input DER-encoded structures. They return one on success and zero on
1140 // failure.
1141 
1142 OPENSSL_EXPORT int SSL_CTX_use_certificate_ASN1(SSL_CTX *ctx, size_t der_len,
1143                                                 const uint8_t *der);
1144 OPENSSL_EXPORT int SSL_use_certificate_ASN1(SSL *ssl, const uint8_t *der,
1145                                             size_t der_len);
1146 
1147 OPENSSL_EXPORT int SSL_CTX_use_PrivateKey_ASN1(int pk, SSL_CTX *ctx,
1148                                                const uint8_t *der,
1149                                                size_t der_len);
1150 OPENSSL_EXPORT int SSL_use_PrivateKey_ASN1(int type, SSL *ssl,
1151                                            const uint8_t *der, size_t der_len);
1152 
1153 OPENSSL_EXPORT int SSL_CTX_use_RSAPrivateKey_ASN1(SSL_CTX *ctx,
1154                                                   const uint8_t *der,
1155                                                   size_t der_len);
1156 OPENSSL_EXPORT int SSL_use_RSAPrivateKey_ASN1(SSL *ssl, const uint8_t *der,
1157                                               size_t der_len);
1158 
1159 // The following functions configure certificates or private keys but take as
1160 // input files to read from. They return one on success and zero on failure. The
1161 // |type| parameter is one of the |SSL_FILETYPE_*| values and determines whether
1162 // the file's contents are read as PEM or DER.
1163 
1164 #define SSL_FILETYPE_PEM 1
1165 #define SSL_FILETYPE_ASN1 2
1166 
1167 OPENSSL_EXPORT int SSL_CTX_use_RSAPrivateKey_file(SSL_CTX *ctx,
1168                                                   const char *file,
1169                                                   int type);
1170 OPENSSL_EXPORT int SSL_use_RSAPrivateKey_file(SSL *ssl, const char *file,
1171                                               int type);
1172 
1173 OPENSSL_EXPORT int SSL_CTX_use_certificate_file(SSL_CTX *ctx, const char *file,
1174                                                 int type);
1175 OPENSSL_EXPORT int SSL_use_certificate_file(SSL *ssl, const char *file,
1176                                             int type);
1177 
1178 OPENSSL_EXPORT int SSL_CTX_use_PrivateKey_file(SSL_CTX *ctx, const char *file,
1179                                                int type);
1180 OPENSSL_EXPORT int SSL_use_PrivateKey_file(SSL *ssl, const char *file,
1181                                            int type);
1182 
1183 // SSL_CTX_use_certificate_chain_file configures certificates for |ctx|. It
1184 // reads the contents of |file| as a PEM-encoded leaf certificate followed
1185 // optionally by the certificate chain to send to the peer. It returns one on
1186 // success and zero on failure.
1187 OPENSSL_EXPORT int SSL_CTX_use_certificate_chain_file(SSL_CTX *ctx,
1188                                                       const char *file);
1189 
1190 // SSL_CTX_set_default_passwd_cb sets the password callback for PEM-based
1191 // convenience functions called on |ctx|.
1192 OPENSSL_EXPORT void SSL_CTX_set_default_passwd_cb(SSL_CTX *ctx,
1193                                                   pem_password_cb *cb);
1194 
1195 // SSL_CTX_get_default_passwd_cb returns the callback set by
1196 // |SSL_CTX_set_default_passwd_cb|.
1197 OPENSSL_EXPORT pem_password_cb *SSL_CTX_get_default_passwd_cb(
1198     const SSL_CTX *ctx);
1199 
1200 // SSL_CTX_set_default_passwd_cb_userdata sets the userdata parameter for
1201 // |ctx|'s password callback.
1202 OPENSSL_EXPORT void SSL_CTX_set_default_passwd_cb_userdata(SSL_CTX *ctx,
1203                                                            void *data);
1204 
1205 // SSL_CTX_get_default_passwd_cb_userdata returns the userdata parameter set by
1206 // |SSL_CTX_set_default_passwd_cb_userdata|.
1207 OPENSSL_EXPORT void *SSL_CTX_get_default_passwd_cb_userdata(const SSL_CTX *ctx);
1208 
1209 
1210 // Custom private keys.
1211 
1212 enum ssl_private_key_result_t BORINGSSL_ENUM_INT {
1213   ssl_private_key_success,
1214   ssl_private_key_retry,
1215   ssl_private_key_failure,
1216 };
1217 
1218 // ssl_private_key_method_st (aka |SSL_PRIVATE_KEY_METHOD|) describes private
1219 // key hooks. This is used to off-load signing operations to a custom,
1220 // potentially asynchronous, backend. Metadata about the key such as the type
1221 // and size are parsed out of the certificate.
1222 //
1223 // Callers that use this structure should additionally call
1224 // |SSL_set_signing_algorithm_prefs| or |SSL_CTX_set_signing_algorithm_prefs|
1225 // with the private key's capabilities. This ensures BoringSSL will select a
1226 // suitable signature algorithm for the private key.
1227 struct ssl_private_key_method_st {
1228   // sign signs the message |in| in using the specified signature algorithm. On
1229   // success, it returns |ssl_private_key_success| and writes at most |max_out|
1230   // bytes of signature data to |out| and sets |*out_len| to the number of bytes
1231   // written. On failure, it returns |ssl_private_key_failure|. If the operation
1232   // has not completed, it returns |ssl_private_key_retry|. |sign| should
1233   // arrange for the high-level operation on |ssl| to be retried when the
1234   // operation is completed. This will result in a call to |complete|.
1235   //
1236   // |signature_algorithm| is one of the |SSL_SIGN_*| values, as defined in TLS
1237   // 1.3. Note that, in TLS 1.2, ECDSA algorithms do not require that curve
1238   // sizes match hash sizes, so the curve portion of |SSL_SIGN_ECDSA_*| values
1239   // must be ignored. BoringSSL will internally handle the curve matching logic
1240   // where appropriate.
1241   //
1242   // It is an error to call |sign| while another private key operation is in
1243   // progress on |ssl|.
1244   enum ssl_private_key_result_t (*sign)(SSL *ssl, uint8_t *out, size_t *out_len,
1245                                         size_t max_out,
1246                                         uint16_t signature_algorithm,
1247                                         const uint8_t *in, size_t in_len);
1248 
1249   // decrypt decrypts |in_len| bytes of encrypted data from |in|. On success it
1250   // returns |ssl_private_key_success|, writes at most |max_out| bytes of
1251   // decrypted data to |out| and sets |*out_len| to the actual number of bytes
1252   // written. On failure it returns |ssl_private_key_failure|. If the operation
1253   // has not completed, it returns |ssl_private_key_retry|. The caller should
1254   // arrange for the high-level operation on |ssl| to be retried when the
1255   // operation is completed, which will result in a call to |complete|. This
1256   // function only works with RSA keys and should perform a raw RSA decryption
1257   // operation with no padding.
1258   //
1259   // It is an error to call |decrypt| while another private key operation is in
1260   // progress on |ssl|.
1261   enum ssl_private_key_result_t (*decrypt)(SSL *ssl, uint8_t *out,
1262                                            size_t *out_len, size_t max_out,
1263                                            const uint8_t *in, size_t in_len);
1264 
1265   // complete completes a pending operation. If the operation has completed, it
1266   // returns |ssl_private_key_success| and writes the result to |out| as in
1267   // |sign|. Otherwise, it returns |ssl_private_key_failure| on failure and
1268   // |ssl_private_key_retry| if the operation is still in progress.
1269   //
1270   // |complete| may be called arbitrarily many times before completion, but it
1271   // is an error to call |complete| if there is no pending operation in progress
1272   // on |ssl|.
1273   enum ssl_private_key_result_t (*complete)(SSL *ssl, uint8_t *out,
1274                                             size_t *out_len, size_t max_out);
1275 };
1276 
1277 // SSL_set_private_key_method configures a custom private key on |ssl|.
1278 // |key_method| must remain valid for the lifetime of |ssl|.
1279 OPENSSL_EXPORT void SSL_set_private_key_method(
1280     SSL *ssl, const SSL_PRIVATE_KEY_METHOD *key_method);
1281 
1282 // SSL_CTX_set_private_key_method configures a custom private key on |ctx|.
1283 // |key_method| must remain valid for the lifetime of |ctx|.
1284 OPENSSL_EXPORT void SSL_CTX_set_private_key_method(
1285     SSL_CTX *ctx, const SSL_PRIVATE_KEY_METHOD *key_method);
1286 
1287 // SSL_can_release_private_key returns one if |ssl| will no longer call into the
1288 // private key and zero otherwise. If the function returns one, the caller can
1289 // release state associated with the private key.
1290 //
1291 // NOTE: This function assumes the caller does not use |SSL_clear| to reuse
1292 // |ssl| for a second connection. If |SSL_clear| is used, BoringSSL may still
1293 // use the private key on the second connection.
1294 OPENSSL_EXPORT int SSL_can_release_private_key(const SSL *ssl);
1295 
1296 
1297 // Cipher suites.
1298 //
1299 // |SSL_CIPHER| objects represent cipher suites.
1300 
1301 DEFINE_CONST_STACK_OF(SSL_CIPHER)
1302 
1303 // SSL_get_cipher_by_value returns the structure representing a TLS cipher
1304 // suite based on its assigned number, or NULL if unknown. See
1305 // https://www.iana.org/assignments/tls-parameters/tls-parameters.xhtml#tls-parameters-4.
1306 OPENSSL_EXPORT const SSL_CIPHER *SSL_get_cipher_by_value(uint16_t value);
1307 
1308 // SSL_CIPHER_get_id returns |cipher|'s non-IANA id. This is not its
1309 // IANA-assigned number, which is called the "value" here, although it may be
1310 // cast to a |uint16_t| to get it.
1311 OPENSSL_EXPORT uint32_t SSL_CIPHER_get_id(const SSL_CIPHER *cipher);
1312 
1313 // SSL_CIPHER_get_protocol_id returns |cipher|'s IANA-assigned number.
1314 OPENSSL_EXPORT uint16_t SSL_CIPHER_get_protocol_id(const SSL_CIPHER *cipher);
1315 
1316 // SSL_CIPHER_is_aead returns one if |cipher| uses an AEAD cipher.
1317 OPENSSL_EXPORT int SSL_CIPHER_is_aead(const SSL_CIPHER *cipher);
1318 
1319 // SSL_CIPHER_is_block_cipher returns one if |cipher| is a block cipher.
1320 OPENSSL_EXPORT int SSL_CIPHER_is_block_cipher(const SSL_CIPHER *cipher);
1321 
1322 // SSL_CIPHER_get_cipher_nid returns the NID for |cipher|'s bulk
1323 // cipher. Possible values are |NID_aes_128_gcm|, |NID_aes_256_gcm|,
1324 // |NID_chacha20_poly1305|, |NID_aes_128_cbc|, |NID_aes_256_cbc|, and
1325 // |NID_des_ede3_cbc|.
1326 OPENSSL_EXPORT int SSL_CIPHER_get_cipher_nid(const SSL_CIPHER *cipher);
1327 
1328 // SSL_CIPHER_get_digest_nid returns the NID for |cipher|'s HMAC if it is a
1329 // legacy cipher suite. For modern AEAD-based ciphers (see
1330 // |SSL_CIPHER_is_aead|), it returns |NID_undef|.
1331 //
1332 // Note this function only returns the legacy HMAC digest, not the PRF hash.
1333 OPENSSL_EXPORT int SSL_CIPHER_get_digest_nid(const SSL_CIPHER *cipher);
1334 
1335 // SSL_CIPHER_get_kx_nid returns the NID for |cipher|'s key exchange. This may
1336 // be |NID_kx_rsa|, |NID_kx_ecdhe|, or |NID_kx_psk| for TLS 1.2. In TLS 1.3,
1337 // cipher suites do not specify the key exchange, so this function returns
1338 // |NID_kx_any|.
1339 OPENSSL_EXPORT int SSL_CIPHER_get_kx_nid(const SSL_CIPHER *cipher);
1340 
1341 // SSL_CIPHER_get_auth_nid returns the NID for |cipher|'s authentication
1342 // type. This may be |NID_auth_rsa|, |NID_auth_ecdsa|, or |NID_auth_psk| for TLS
1343 // 1.2. In TLS 1.3, cipher suites do not specify authentication, so this
1344 // function returns |NID_auth_any|.
1345 OPENSSL_EXPORT int SSL_CIPHER_get_auth_nid(const SSL_CIPHER *cipher);
1346 
1347 // SSL_CIPHER_get_prf_nid retuns the NID for |cipher|'s PRF hash. If |cipher| is
1348 // a pre-TLS-1.2 cipher, it returns |NID_md5_sha1| but note these ciphers use
1349 // SHA-256 in TLS 1.2. Other return values may be treated uniformly in all
1350 // applicable versions.
1351 OPENSSL_EXPORT int SSL_CIPHER_get_prf_nid(const SSL_CIPHER *cipher);
1352 
1353 // SSL_CIPHER_get_min_version returns the minimum protocol version required
1354 // for |cipher|.
1355 OPENSSL_EXPORT uint16_t SSL_CIPHER_get_min_version(const SSL_CIPHER *cipher);
1356 
1357 // SSL_CIPHER_get_max_version returns the maximum protocol version that
1358 // supports |cipher|.
1359 OPENSSL_EXPORT uint16_t SSL_CIPHER_get_max_version(const SSL_CIPHER *cipher);
1360 
1361 // SSL_CIPHER_standard_name returns the standard IETF name for |cipher|. For
1362 // example, "TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256".
1363 OPENSSL_EXPORT const char *SSL_CIPHER_standard_name(const SSL_CIPHER *cipher);
1364 
1365 // SSL_CIPHER_get_name returns the OpenSSL name of |cipher|. For example,
1366 // "ECDHE-RSA-AES128-GCM-SHA256". Callers are recommended to use
1367 // |SSL_CIPHER_standard_name| instead.
1368 OPENSSL_EXPORT const char *SSL_CIPHER_get_name(const SSL_CIPHER *cipher);
1369 
1370 // SSL_CIPHER_get_kx_name returns a string that describes the key-exchange
1371 // method used by |cipher|. For example, "ECDHE_ECDSA". TLS 1.3 AEAD-only
1372 // ciphers return the string "GENERIC".
1373 OPENSSL_EXPORT const char *SSL_CIPHER_get_kx_name(const SSL_CIPHER *cipher);
1374 
1375 // SSL_CIPHER_get_bits returns the strength, in bits, of |cipher|. If
1376 // |out_alg_bits| is not NULL, it writes the number of bits consumed by the
1377 // symmetric algorithm to |*out_alg_bits|.
1378 OPENSSL_EXPORT int SSL_CIPHER_get_bits(const SSL_CIPHER *cipher,
1379                                        int *out_alg_bits);
1380 
1381 
1382 // Cipher suite configuration.
1383 //
1384 // OpenSSL uses a mini-language to configure cipher suites. The language
1385 // maintains an ordered list of enabled ciphers, along with an ordered list of
1386 // disabled but available ciphers. Initially, all ciphers are disabled with a
1387 // default ordering. The cipher string is then interpreted as a sequence of
1388 // directives, separated by colons, each of which modifies this state.
1389 //
1390 // Most directives consist of a one character or empty opcode followed by a
1391 // selector which matches a subset of available ciphers.
1392 //
1393 // Available opcodes are:
1394 //
1395 //   The empty opcode enables and appends all matching disabled ciphers to the
1396 //   end of the enabled list. The newly appended ciphers are ordered relative to
1397 //   each other matching their order in the disabled list.
1398 //
1399 //   |-| disables all matching enabled ciphers and prepends them to the disabled
1400 //   list, with relative order from the enabled list preserved. This means the
1401 //   most recently disabled ciphers get highest preference relative to other
1402 //   disabled ciphers if re-enabled.
1403 //
1404 //   |+| moves all matching enabled ciphers to the end of the enabled list, with
1405 //   relative order preserved.
1406 //
1407 //   |!| deletes all matching ciphers, enabled or not, from either list. Deleted
1408 //   ciphers will not matched by future operations.
1409 //
1410 // A selector may be a specific cipher (using either the standard or OpenSSL
1411 // name for the cipher) or one or more rules separated by |+|. The final
1412 // selector matches the intersection of each rule. For instance, |AESGCM+aECDSA|
1413 // matches ECDSA-authenticated AES-GCM ciphers.
1414 //
1415 // Available cipher rules are:
1416 //
1417 //   |ALL| matches all ciphers.
1418 //
1419 //   |kRSA|, |kDHE|, |kECDHE|, and |kPSK| match ciphers using plain RSA, DHE,
1420 //   ECDHE, and plain PSK key exchanges, respectively. Note that ECDHE_PSK is
1421 //   matched by |kECDHE| and not |kPSK|.
1422 //
1423 //   |aRSA|, |aECDSA|, and |aPSK| match ciphers authenticated by RSA, ECDSA, and
1424 //   a pre-shared key, respectively.
1425 //
1426 //   |RSA|, |DHE|, |ECDHE|, |PSK|, |ECDSA|, and |PSK| are aliases for the
1427 //   corresponding |k*| or |a*| cipher rule. |RSA| is an alias for |kRSA|, not
1428 //   |aRSA|.
1429 //
1430 //   |3DES|, |AES128|, |AES256|, |AES|, |AESGCM|, |CHACHA20| match ciphers
1431 //   whose bulk cipher use the corresponding encryption scheme. Note that
1432 //   |AES|, |AES128|, and |AES256| match both CBC and GCM ciphers.
1433 //
1434 //   |SHA1|, and its alias |SHA|, match legacy cipher suites using HMAC-SHA1.
1435 //
1436 // Although implemented, authentication-only ciphers match no rules and must be
1437 // explicitly selected by name.
1438 //
1439 // Deprecated cipher rules:
1440 //
1441 //   |kEDH|, |EDH|, |kEECDH|, and |EECDH| are legacy aliases for |kDHE|, |DHE|,
1442 //   |kECDHE|, and |ECDHE|, respectively.
1443 //
1444 //   |HIGH| is an alias for |ALL|.
1445 //
1446 //   |FIPS| is an alias for |HIGH|.
1447 //
1448 //   |SSLv3| and |TLSv1| match ciphers available in TLS 1.1 or earlier.
1449 //   |TLSv1_2| matches ciphers new in TLS 1.2. This is confusing and should not
1450 //   be used.
1451 //
1452 // Unknown rules are silently ignored by legacy APIs, and rejected by APIs with
1453 // "strict" in the name, which should be preferred. Cipher lists can be long
1454 // and it's easy to commit typos. Strict functions will also reject the use of
1455 // spaces, semi-colons and commas as alternative separators.
1456 //
1457 // The special |@STRENGTH| directive will sort all enabled ciphers by strength.
1458 //
1459 // The |DEFAULT| directive, when appearing at the front of the string, expands
1460 // to the default ordering of available ciphers.
1461 //
1462 // If configuring a server, one may also configure equal-preference groups to
1463 // partially respect the client's preferences when
1464 // |SSL_OP_CIPHER_SERVER_PREFERENCE| is enabled. Ciphers in an equal-preference
1465 // group have equal priority and use the client order. This may be used to
1466 // enforce that AEADs are preferred but select AES-GCM vs. ChaCha20-Poly1305
1467 // based on client preferences. An equal-preference is specified with square
1468 // brackets, combining multiple selectors separated by |. For example:
1469 //
1470 //   [TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256|TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256]
1471 //
1472 // Once an equal-preference group is used, future directives must be
1473 // opcode-less. Inside an equal-preference group, spaces are not allowed.
1474 //
1475 // TLS 1.3 ciphers do not participate in this mechanism and instead have a
1476 // built-in preference order. Functions to set cipher lists do not affect TLS
1477 // 1.3, and functions to query the cipher list do not include TLS 1.3
1478 // ciphers.
1479 
1480 // SSL_DEFAULT_CIPHER_LIST is the default cipher suite configuration. It is
1481 // substituted when a cipher string starts with 'DEFAULT'.
1482 #define SSL_DEFAULT_CIPHER_LIST "ALL"
1483 
1484 // SSL_CTX_set_strict_cipher_list configures the cipher list for |ctx|,
1485 // evaluating |str| as a cipher string and returning error if |str| contains
1486 // anything meaningless. It returns one on success and zero on failure.
1487 OPENSSL_EXPORT int SSL_CTX_set_strict_cipher_list(SSL_CTX *ctx,
1488                                                   const char *str);
1489 
1490 // SSL_CTX_set_cipher_list configures the cipher list for |ctx|, evaluating
1491 // |str| as a cipher string. It returns one on success and zero on failure.
1492 //
1493 // Prefer to use |SSL_CTX_set_strict_cipher_list|. This function tolerates
1494 // garbage inputs, unless an empty cipher list results.
1495 OPENSSL_EXPORT int SSL_CTX_set_cipher_list(SSL_CTX *ctx, const char *str);
1496 
1497 // SSL_set_strict_cipher_list configures the cipher list for |ssl|, evaluating
1498 // |str| as a cipher string and returning error if |str| contains anything
1499 // meaningless. It returns one on success and zero on failure.
1500 OPENSSL_EXPORT int SSL_set_strict_cipher_list(SSL *ssl, const char *str);
1501 
1502 // SSL_set_cipher_list configures the cipher list for |ssl|, evaluating |str| as
1503 // a cipher string. It returns one on success and zero on failure.
1504 //
1505 // Prefer to use |SSL_set_strict_cipher_list|. This function tolerates garbage
1506 // inputs, unless an empty cipher list results.
1507 OPENSSL_EXPORT int SSL_set_cipher_list(SSL *ssl, const char *str);
1508 
1509 // SSL_CTX_get_ciphers returns the cipher list for |ctx|, in order of
1510 // preference.
1511 OPENSSL_EXPORT STACK_OF(SSL_CIPHER) *SSL_CTX_get_ciphers(const SSL_CTX *ctx);
1512 
1513 // SSL_CTX_cipher_in_group returns one if the |i|th cipher (see
1514 // |SSL_CTX_get_ciphers|) is in the same equipreference group as the one
1515 // following it and zero otherwise.
1516 OPENSSL_EXPORT int SSL_CTX_cipher_in_group(const SSL_CTX *ctx, size_t i);
1517 
1518 // SSL_get_ciphers returns the cipher list for |ssl|, in order of preference.
1519 OPENSSL_EXPORT STACK_OF(SSL_CIPHER) *SSL_get_ciphers(const SSL *ssl);
1520 
1521 
1522 // Connection information.
1523 
1524 // SSL_is_init_finished returns one if |ssl| has completed its initial handshake
1525 // and has no pending handshake. It returns zero otherwise.
1526 OPENSSL_EXPORT int SSL_is_init_finished(const SSL *ssl);
1527 
1528 // SSL_in_init returns one if |ssl| has a pending handshake and zero
1529 // otherwise.
1530 OPENSSL_EXPORT int SSL_in_init(const SSL *ssl);
1531 
1532 // SSL_in_false_start returns one if |ssl| has a pending handshake that is in
1533 // False Start. |SSL_write| may be called at this point without waiting for the
1534 // peer, but |SSL_read| will complete the handshake before accepting application
1535 // data.
1536 //
1537 // See also |SSL_MODE_ENABLE_FALSE_START|.
1538 OPENSSL_EXPORT int SSL_in_false_start(const SSL *ssl);
1539 
1540 // SSL_get_peer_certificate returns the peer's leaf certificate or NULL if the
1541 // peer did not use certificates. The caller must call |X509_free| on the
1542 // result to release it.
1543 OPENSSL_EXPORT X509 *SSL_get_peer_certificate(const SSL *ssl);
1544 
1545 // SSL_get_peer_cert_chain returns the peer's certificate chain or NULL if
1546 // unavailable or the peer did not use certificates. This is the unverified list
1547 // of certificates as sent by the peer, not the final chain built during
1548 // verification. The caller does not take ownership of the result.
1549 //
1550 // WARNING: This function behaves differently between client and server. If
1551 // |ssl| is a server, the returned chain does not include the leaf certificate.
1552 // If a client, it does.
1553 OPENSSL_EXPORT STACK_OF(X509) *SSL_get_peer_cert_chain(const SSL *ssl);
1554 
1555 // SSL_get_peer_full_cert_chain returns the peer's certificate chain, or NULL if
1556 // unavailable or the peer did not use certificates. This is the unverified list
1557 // of certificates as sent by the peer, not the final chain built during
1558 // verification. The caller does not take ownership of the result.
1559 //
1560 // This is the same as |SSL_get_peer_cert_chain| except that this function
1561 // always returns the full chain, i.e. the first element of the return value
1562 // (if any) will be the leaf certificate. In constrast,
1563 // |SSL_get_peer_cert_chain| returns only the intermediate certificates if the
1564 // |ssl| is a server.
1565 OPENSSL_EXPORT STACK_OF(X509) *SSL_get_peer_full_cert_chain(const SSL *ssl);
1566 
1567 // SSL_get0_peer_certificates returns the peer's certificate chain, or NULL if
1568 // unavailable or the peer did not use certificates. This is the unverified list
1569 // of certificates as sent by the peer, not the final chain built during
1570 // verification. The caller does not take ownership of the result.
1571 //
1572 // This is the |CRYPTO_BUFFER| variant of |SSL_get_peer_full_cert_chain|.
1573 OPENSSL_EXPORT const STACK_OF(CRYPTO_BUFFER) *
1574     SSL_get0_peer_certificates(const SSL *ssl);
1575 
1576 // SSL_get0_signed_cert_timestamp_list sets |*out| and |*out_len| to point to
1577 // |*out_len| bytes of SCT information from the server. This is only valid if
1578 // |ssl| is a client. The SCT information is a SignedCertificateTimestampList
1579 // (including the two leading length bytes).
1580 // See https://tools.ietf.org/html/rfc6962#section-3.3
1581 // If no SCT was received then |*out_len| will be zero on return.
1582 //
1583 // WARNING: the returned data is not guaranteed to be well formed.
1584 OPENSSL_EXPORT void SSL_get0_signed_cert_timestamp_list(const SSL *ssl,
1585                                                         const uint8_t **out,
1586                                                         size_t *out_len);
1587 
1588 // SSL_get0_ocsp_response sets |*out| and |*out_len| to point to |*out_len|
1589 // bytes of an OCSP response from the server. This is the DER encoding of an
1590 // OCSPResponse type as defined in RFC 2560.
1591 //
1592 // WARNING: the returned data is not guaranteed to be well formed.
1593 OPENSSL_EXPORT void SSL_get0_ocsp_response(const SSL *ssl, const uint8_t **out,
1594                                            size_t *out_len);
1595 
1596 // SSL_get_tls_unique writes at most |max_out| bytes of the tls-unique value
1597 // for |ssl| to |out| and sets |*out_len| to the number of bytes written. It
1598 // returns one on success or zero on error. In general |max_out| should be at
1599 // least 12.
1600 //
1601 // This function will always fail if the initial handshake has not completed.
1602 // The tls-unique value will change after a renegotiation but, since
1603 // renegotiations can be initiated by the server at any point, the higher-level
1604 // protocol must either leave them disabled or define states in which the
1605 // tls-unique value can be read.
1606 //
1607 // The tls-unique value is defined by
1608 // https://tools.ietf.org/html/rfc5929#section-3.1. Due to a weakness in the
1609 // TLS protocol, tls-unique is broken for resumed connections unless the
1610 // Extended Master Secret extension is negotiated. Thus this function will
1611 // return zero if |ssl| performed session resumption unless EMS was used when
1612 // negotiating the original session.
1613 OPENSSL_EXPORT int SSL_get_tls_unique(const SSL *ssl, uint8_t *out,
1614                                       size_t *out_len, size_t max_out);
1615 
1616 // SSL_get_extms_support returns one if the Extended Master Secret extension or
1617 // TLS 1.3 was negotiated. Otherwise, it returns zero.
1618 OPENSSL_EXPORT int SSL_get_extms_support(const SSL *ssl);
1619 
1620 // SSL_get_current_cipher returns cipher suite used by |ssl|, or NULL if it has
1621 // not been negotiated yet.
1622 OPENSSL_EXPORT const SSL_CIPHER *SSL_get_current_cipher(const SSL *ssl);
1623 
1624 // SSL_session_reused returns one if |ssl| performed an abbreviated handshake
1625 // and zero otherwise.
1626 //
1627 // TODO(davidben): Hammer down the semantics of this API while a handshake,
1628 // initial or renego, is in progress.
1629 OPENSSL_EXPORT int SSL_session_reused(const SSL *ssl);
1630 
1631 // SSL_get_secure_renegotiation_support returns one if the peer supports secure
1632 // renegotiation (RFC 5746) or TLS 1.3. Otherwise, it returns zero.
1633 OPENSSL_EXPORT int SSL_get_secure_renegotiation_support(const SSL *ssl);
1634 
1635 // SSL_export_keying_material exports a value derived from the master secret, as
1636 // specified in RFC 5705. It writes |out_len| bytes to |out| given a label and
1637 // optional context. (Since a zero length context is allowed, the |use_context|
1638 // flag controls whether a context is included.)
1639 //
1640 // It returns one on success and zero otherwise.
1641 OPENSSL_EXPORT int SSL_export_keying_material(
1642     SSL *ssl, uint8_t *out, size_t out_len, const char *label, size_t label_len,
1643     const uint8_t *context, size_t context_len, int use_context);
1644 
1645 
1646 // Sessions.
1647 //
1648 // An |SSL_SESSION| represents an SSL session that may be resumed in an
1649 // abbreviated handshake. It is reference-counted and immutable. Once
1650 // established, an |SSL_SESSION| may be shared by multiple |SSL| objects on
1651 // different threads and must not be modified.
1652 
1653 DECLARE_PEM_rw(SSL_SESSION, SSL_SESSION)
1654 
1655 // SSL_SESSION_new returns a newly-allocated blank |SSL_SESSION| or NULL on
1656 // error. This may be useful when writing tests but should otherwise not be
1657 // used.
1658 OPENSSL_EXPORT SSL_SESSION *SSL_SESSION_new(const SSL_CTX *ctx);
1659 
1660 // SSL_SESSION_up_ref increments the reference count of |session| and returns
1661 // one.
1662 OPENSSL_EXPORT int SSL_SESSION_up_ref(SSL_SESSION *session);
1663 
1664 // SSL_SESSION_free decrements the reference count of |session|. If it reaches
1665 // zero, all data referenced by |session| and |session| itself are released.
1666 OPENSSL_EXPORT void SSL_SESSION_free(SSL_SESSION *session);
1667 
1668 // SSL_SESSION_to_bytes serializes |in| into a newly allocated buffer and sets
1669 // |*out_data| to that buffer and |*out_len| to its length. The caller takes
1670 // ownership of the buffer and must call |OPENSSL_free| when done. It returns
1671 // one on success and zero on error.
1672 OPENSSL_EXPORT int SSL_SESSION_to_bytes(const SSL_SESSION *in,
1673                                         uint8_t **out_data, size_t *out_len);
1674 
1675 // SSL_SESSION_to_bytes_for_ticket serializes |in|, but excludes the session
1676 // identification information, namely the session ID and ticket.
1677 OPENSSL_EXPORT int SSL_SESSION_to_bytes_for_ticket(const SSL_SESSION *in,
1678                                                    uint8_t **out_data,
1679                                                    size_t *out_len);
1680 
1681 // SSL_SESSION_from_bytes parses |in_len| bytes from |in| as an SSL_SESSION. It
1682 // returns a newly-allocated |SSL_SESSION| on success or NULL on error.
1683 OPENSSL_EXPORT SSL_SESSION *SSL_SESSION_from_bytes(
1684     const uint8_t *in, size_t in_len, const SSL_CTX *ctx);
1685 
1686 // SSL_SESSION_get_version returns a string describing the TLS or DTLS version
1687 // |session| was established at. For example, "TLSv1.2" or "DTLSv1".
1688 OPENSSL_EXPORT const char *SSL_SESSION_get_version(const SSL_SESSION *session);
1689 
1690 // SSL_SESSION_get_protocol_version returns the TLS or DTLS version |session|
1691 // was established at.
1692 OPENSSL_EXPORT uint16_t
1693 SSL_SESSION_get_protocol_version(const SSL_SESSION *session);
1694 
1695 // SSL_SESSION_set_protocol_version sets |session|'s TLS or DTLS version to
1696 // |version|. This may be useful when writing tests but should otherwise not be
1697 // used. It returns one on success and zero on error.
1698 OPENSSL_EXPORT int SSL_SESSION_set_protocol_version(SSL_SESSION *session,
1699                                                     uint16_t version);
1700 
1701 // SSL_MAX_SSL_SESSION_ID_LENGTH is the maximum length of an SSL session ID.
1702 #define SSL_MAX_SSL_SESSION_ID_LENGTH 32
1703 
1704 // SSL_SESSION_get_id returns a pointer to a buffer containing |session|'s
1705 // session ID and sets |*out_len| to its length.
1706 OPENSSL_EXPORT const uint8_t *SSL_SESSION_get_id(const SSL_SESSION *session,
1707                                                  unsigned *out_len);
1708 
1709 // SSL_SESSION_set1_id sets |session|'s session ID to |sid|, It returns one on
1710 // success and zero on error. This function may be useful in writing tests but
1711 // otherwise should not be used.
1712 OPENSSL_EXPORT int SSL_SESSION_set1_id(SSL_SESSION *session, const uint8_t *sid,
1713                                        size_t sid_len);
1714 
1715 // SSL_SESSION_get_time returns the time at which |session| was established in
1716 // seconds since the UNIX epoch.
1717 OPENSSL_EXPORT uint64_t SSL_SESSION_get_time(const SSL_SESSION *session);
1718 
1719 // SSL_SESSION_get_timeout returns the lifetime of |session| in seconds.
1720 OPENSSL_EXPORT uint32_t SSL_SESSION_get_timeout(const SSL_SESSION *session);
1721 
1722 // SSL_SESSION_get0_peer returns the peer leaf certificate stored in
1723 // |session|.
1724 //
1725 // TODO(davidben): This should return a const X509 *.
1726 OPENSSL_EXPORT X509 *SSL_SESSION_get0_peer(const SSL_SESSION *session);
1727 
1728 // SSL_SESSION_get0_peer_certificates returns the peer certificate chain stored
1729 // in |session|, or NULL if the peer did not use certificates. This is the
1730 // unverified list of certificates as sent by the peer, not the final chain
1731 // built during verification. The caller does not take ownership of the result.
1732 OPENSSL_EXPORT const STACK_OF(CRYPTO_BUFFER) *
1733     SSL_SESSION_get0_peer_certificates(const SSL_SESSION *session);
1734 
1735 // SSL_SESSION_get0_signed_cert_timestamp_list sets |*out| and |*out_len| to
1736 // point to |*out_len| bytes of SCT information stored in |session|. This is
1737 // only valid for client sessions. The SCT information is a
1738 // SignedCertificateTimestampList (including the two leading length bytes). See
1739 // https://tools.ietf.org/html/rfc6962#section-3.3 If no SCT was received then
1740 // |*out_len| will be zero on return.
1741 //
1742 // WARNING: the returned data is not guaranteed to be well formed.
1743 OPENSSL_EXPORT void SSL_SESSION_get0_signed_cert_timestamp_list(
1744     const SSL_SESSION *session, const uint8_t **out, size_t *out_len);
1745 
1746 // SSL_SESSION_get0_ocsp_response sets |*out| and |*out_len| to point to
1747 // |*out_len| bytes of an OCSP response from the server. This is the DER
1748 // encoding of an OCSPResponse type as defined in RFC 2560.
1749 //
1750 // WARNING: the returned data is not guaranteed to be well formed.
1751 OPENSSL_EXPORT void SSL_SESSION_get0_ocsp_response(const SSL_SESSION *session,
1752                                                    const uint8_t **out,
1753                                                    size_t *out_len);
1754 
1755 // SSL_MAX_MASTER_KEY_LENGTH is the maximum length of a master secret.
1756 #define SSL_MAX_MASTER_KEY_LENGTH 48
1757 
1758 // SSL_SESSION_get_master_key writes up to |max_out| bytes of |session|'s secret
1759 // to |out| and returns the number of bytes written. If |max_out| is zero, it
1760 // returns the size of the secret.
1761 OPENSSL_EXPORT size_t SSL_SESSION_get_master_key(const SSL_SESSION *session,
1762                                                  uint8_t *out, size_t max_out);
1763 
1764 // SSL_SESSION_set_time sets |session|'s creation time to |time| and returns
1765 // |time|. This function may be useful in writing tests but otherwise should not
1766 // be used.
1767 OPENSSL_EXPORT uint64_t SSL_SESSION_set_time(SSL_SESSION *session,
1768                                              uint64_t time);
1769 
1770 // SSL_SESSION_set_timeout sets |session|'s timeout to |timeout| and returns
1771 // one. This function may be useful in writing tests but otherwise should not
1772 // be used.
1773 OPENSSL_EXPORT uint32_t SSL_SESSION_set_timeout(SSL_SESSION *session,
1774                                                 uint32_t timeout);
1775 
1776 // SSL_SESSION_get0_id_context returns a pointer to a buffer containing
1777 // |session|'s session ID context (see |SSL_CTX_set_session_id_context|) and
1778 // sets |*out_len| to its length.
1779 OPENSSL_EXPORT const uint8_t *SSL_SESSION_get0_id_context(
1780     const SSL_SESSION *session, unsigned *out_len);
1781 
1782 // SSL_SESSION_set1_id_context sets |session|'s session ID context (see
1783 // |SSL_CTX_set_session_id_context|) to |sid_ctx|. It returns one on success and
1784 // zero on error. This function may be useful in writing tests but otherwise
1785 // should not be used.
1786 OPENSSL_EXPORT int SSL_SESSION_set1_id_context(SSL_SESSION *session,
1787                                                const uint8_t *sid_ctx,
1788                                                size_t sid_ctx_len);
1789 
1790 // SSL_SESSION_should_be_single_use returns one if |session| should be
1791 // single-use (TLS 1.3 and later) and zero otherwise.
1792 //
1793 // If this function returns one, clients retain multiple sessions and use each
1794 // only once. This prevents passive observers from correlating connections with
1795 // tickets. See RFC 8446, appendix C.4. If it returns zero, |session| cannot be
1796 // used without leaking a correlator.
1797 OPENSSL_EXPORT int SSL_SESSION_should_be_single_use(const SSL_SESSION *session);
1798 
1799 // SSL_SESSION_is_resumable returns one if |session| is complete and contains a
1800 // session ID or ticket. It returns zero otherwise. Note this function does not
1801 // ensure |session| will be resumed. It may be expired, dropped by the server,
1802 // or associated with incompatible parameters.
1803 OPENSSL_EXPORT int SSL_SESSION_is_resumable(const SSL_SESSION *session);
1804 
1805 // SSL_SESSION_has_ticket returns one if |session| has a ticket and zero
1806 // otherwise.
1807 OPENSSL_EXPORT int SSL_SESSION_has_ticket(const SSL_SESSION *session);
1808 
1809 // SSL_SESSION_get0_ticket sets |*out_ticket| and |*out_len| to |session|'s
1810 // ticket, or NULL and zero if it does not have one. |out_ticket| may be NULL
1811 // if only the ticket length is needed.
1812 OPENSSL_EXPORT void SSL_SESSION_get0_ticket(const SSL_SESSION *session,
1813                                             const uint8_t **out_ticket,
1814                                             size_t *out_len);
1815 
1816 // SSL_SESSION_set_ticket sets |session|'s ticket to |ticket|. It returns one on
1817 // success and zero on error. This function may be useful in writing tests but
1818 // otherwise should not be used.
1819 OPENSSL_EXPORT int SSL_SESSION_set_ticket(SSL_SESSION *session,
1820                                           const uint8_t *ticket,
1821                                           size_t ticket_len);
1822 
1823 // SSL_SESSION_get_ticket_lifetime_hint returns ticket lifetime hint of
1824 // |session| in seconds or zero if none was set.
1825 OPENSSL_EXPORT uint32_t
1826 SSL_SESSION_get_ticket_lifetime_hint(const SSL_SESSION *session);
1827 
1828 // SSL_SESSION_get0_cipher returns the cipher negotiated by the connection which
1829 // established |session|.
1830 //
1831 // Note that, in TLS 1.3, there is no guarantee that resumptions with |session|
1832 // will use that cipher. Prefer calling |SSL_get_current_cipher| on the |SSL|
1833 // instead.
1834 OPENSSL_EXPORT const SSL_CIPHER *SSL_SESSION_get0_cipher(
1835     const SSL_SESSION *session);
1836 
1837 // SSL_SESSION_has_peer_sha256 returns one if |session| has a SHA-256 hash of
1838 // the peer's certificate retained and zero if the peer did not present a
1839 // certificate or if this was not enabled when |session| was created. See also
1840 // |SSL_CTX_set_retain_only_sha256_of_client_certs|.
1841 OPENSSL_EXPORT int SSL_SESSION_has_peer_sha256(const SSL_SESSION *session);
1842 
1843 // SSL_SESSION_get0_peer_sha256 sets |*out_ptr| and |*out_len| to the SHA-256
1844 // hash of the peer certificate retained in |session|, or NULL and zero if it
1845 // does not have one. See also |SSL_CTX_set_retain_only_sha256_of_client_certs|.
1846 OPENSSL_EXPORT void SSL_SESSION_get0_peer_sha256(const SSL_SESSION *session,
1847                                                  const uint8_t **out_ptr,
1848                                                  size_t *out_len);
1849 
1850 
1851 // Session caching.
1852 //
1853 // Session caching allows connections to be established more efficiently based
1854 // on saved parameters from a previous connection, called a session (see
1855 // |SSL_SESSION|). The client offers a saved session, using an opaque identifier
1856 // from a previous connection. The server may accept the session, if it has the
1857 // parameters available. Otherwise, it will decline and continue with a full
1858 // handshake.
1859 //
1860 // This requires both the client and the server to retain session state. A
1861 // client does so with a stateful session cache. A server may do the same or, if
1862 // supported by both sides, statelessly using session tickets. For more
1863 // information on the latter, see the next section.
1864 //
1865 // For a server, the library implements a built-in internal session cache as an
1866 // in-memory hash table. Servers may also use |SSL_CTX_sess_set_get_cb| and
1867 // |SSL_CTX_sess_set_new_cb| to implement a custom external session cache. In
1868 // particular, this may be used to share a session cache between multiple
1869 // servers in a large deployment. An external cache may be used in addition to
1870 // or instead of the internal one. Use |SSL_CTX_set_session_cache_mode| to
1871 // toggle the internal cache.
1872 //
1873 // For a client, the only option is an external session cache. Clients may use
1874 // |SSL_CTX_sess_set_new_cb| to register a callback for when new sessions are
1875 // available. These may be cached and, in subsequent compatible connections,
1876 // configured with |SSL_set_session|.
1877 //
1878 // Note that offering or accepting a session short-circuits certificate
1879 // verification and most parameter negotiation. Resuming sessions across
1880 // different contexts may result in security failures and surprising
1881 // behavior. For a typical client, this means sessions for different hosts must
1882 // be cached under different keys. A client that connects to the same host with,
1883 // e.g., different cipher suite settings or client certificates should also use
1884 // separate session caches between those contexts. Servers should also partition
1885 // session caches between SNI hosts with |SSL_CTX_set_session_id_context|.
1886 //
1887 // Note also, in TLS 1.2 and earlier, offering sessions allows passive observers
1888 // to correlate different client connections. TLS 1.3 and later fix this,
1889 // provided clients use sessions at most once. Session caches are managed by the
1890 // caller in BoringSSL, so this must be implemented externally. See
1891 // |SSL_SESSION_should_be_single_use| for details.
1892 
1893 // SSL_SESS_CACHE_OFF disables all session caching.
1894 #define SSL_SESS_CACHE_OFF 0x0000
1895 
1896 // SSL_SESS_CACHE_CLIENT enables session caching for a client. The internal
1897 // cache is never used on a client, so this only enables the callbacks.
1898 #define SSL_SESS_CACHE_CLIENT 0x0001
1899 
1900 // SSL_SESS_CACHE_SERVER enables session caching for a server.
1901 #define SSL_SESS_CACHE_SERVER 0x0002
1902 
1903 // SSL_SESS_CACHE_BOTH enables session caching for both client and server.
1904 #define SSL_SESS_CACHE_BOTH (SSL_SESS_CACHE_CLIENT | SSL_SESS_CACHE_SERVER)
1905 
1906 // SSL_SESS_CACHE_NO_AUTO_CLEAR disables automatically calling
1907 // |SSL_CTX_flush_sessions| every 255 connections.
1908 #define SSL_SESS_CACHE_NO_AUTO_CLEAR 0x0080
1909 
1910 // SSL_SESS_CACHE_NO_INTERNAL_LOOKUP, on a server, disables looking up a session
1911 // from the internal session cache.
1912 #define SSL_SESS_CACHE_NO_INTERNAL_LOOKUP 0x0100
1913 
1914 // SSL_SESS_CACHE_NO_INTERNAL_STORE, on a server, disables storing sessions in
1915 // the internal session cache.
1916 #define SSL_SESS_CACHE_NO_INTERNAL_STORE 0x0200
1917 
1918 // SSL_SESS_CACHE_NO_INTERNAL, on a server, disables the internal session
1919 // cache.
1920 #define SSL_SESS_CACHE_NO_INTERNAL \
1921     (SSL_SESS_CACHE_NO_INTERNAL_LOOKUP | SSL_SESS_CACHE_NO_INTERNAL_STORE)
1922 
1923 // SSL_CTX_set_session_cache_mode sets the session cache mode bits for |ctx| to
1924 // |mode|. It returns the previous value.
1925 OPENSSL_EXPORT int SSL_CTX_set_session_cache_mode(SSL_CTX *ctx, int mode);
1926 
1927 // SSL_CTX_get_session_cache_mode returns the session cache mode bits for
1928 // |ctx|
1929 OPENSSL_EXPORT int SSL_CTX_get_session_cache_mode(const SSL_CTX *ctx);
1930 
1931 // SSL_set_session, for a client, configures |ssl| to offer to resume |session|
1932 // in the initial handshake and returns one. The caller retains ownership of
1933 // |session|. Note that configuring a session assumes the authentication in the
1934 // session is valid. For callers that wish to revalidate the session before
1935 // offering, see |SSL_SESSION_get0_peer_certificates|,
1936 // |SSL_SESSION_get0_signed_cert_timestamp_list|, and
1937 // |SSL_SESSION_get0_ocsp_response|.
1938 //
1939 // It is an error to call this function after the handshake has begun.
1940 OPENSSL_EXPORT int SSL_set_session(SSL *ssl, SSL_SESSION *session);
1941 
1942 // SSL_DEFAULT_SESSION_TIMEOUT is the default lifetime, in seconds, of a
1943 // session in TLS 1.2 or earlier. This is how long we are willing to use the
1944 // secret to encrypt traffic without fresh key material.
1945 #define SSL_DEFAULT_SESSION_TIMEOUT (2 * 60 * 60)
1946 
1947 // SSL_DEFAULT_SESSION_PSK_DHE_TIMEOUT is the default lifetime, in seconds, of a
1948 // session for TLS 1.3 psk_dhe_ke. This is how long we are willing to use the
1949 // secret as an authenticator.
1950 #define SSL_DEFAULT_SESSION_PSK_DHE_TIMEOUT (2 * 24 * 60 * 60)
1951 
1952 // SSL_DEFAULT_SESSION_AUTH_TIMEOUT is the default non-renewable lifetime, in
1953 // seconds, of a TLS 1.3 session. This is how long we are willing to trust the
1954 // signature in the initial handshake.
1955 #define SSL_DEFAULT_SESSION_AUTH_TIMEOUT (7 * 24 * 60 * 60)
1956 
1957 // SSL_CTX_set_timeout sets the lifetime, in seconds, of TLS 1.2 (or earlier)
1958 // sessions created in |ctx| to |timeout|.
1959 OPENSSL_EXPORT uint32_t SSL_CTX_set_timeout(SSL_CTX *ctx, uint32_t timeout);
1960 
1961 // SSL_CTX_set_session_psk_dhe_timeout sets the lifetime, in seconds, of TLS 1.3
1962 // sessions created in |ctx| to |timeout|.
1963 OPENSSL_EXPORT void SSL_CTX_set_session_psk_dhe_timeout(SSL_CTX *ctx,
1964                                                         uint32_t timeout);
1965 
1966 // SSL_CTX_get_timeout returns the lifetime, in seconds, of TLS 1.2 (or earlier)
1967 // sessions created in |ctx|.
1968 OPENSSL_EXPORT uint32_t SSL_CTX_get_timeout(const SSL_CTX *ctx);
1969 
1970 // SSL_MAX_SID_CTX_LENGTH is the maximum length of a session ID context.
1971 #define SSL_MAX_SID_CTX_LENGTH 32
1972 
1973 // SSL_CTX_set_session_id_context sets |ctx|'s session ID context to |sid_ctx|.
1974 // It returns one on success and zero on error. The session ID context is an
1975 // application-defined opaque byte string. A session will not be used in a
1976 // connection without a matching session ID context.
1977 //
1978 // For a server, if |SSL_VERIFY_PEER| is enabled, it is an error to not set a
1979 // session ID context.
1980 OPENSSL_EXPORT int SSL_CTX_set_session_id_context(SSL_CTX *ctx,
1981                                                   const uint8_t *sid_ctx,
1982                                                   size_t sid_ctx_len);
1983 
1984 // SSL_set_session_id_context sets |ssl|'s session ID context to |sid_ctx|. It
1985 // returns one on success and zero on error. See also
1986 // |SSL_CTX_set_session_id_context|.
1987 OPENSSL_EXPORT int SSL_set_session_id_context(SSL *ssl, const uint8_t *sid_ctx,
1988                                               size_t sid_ctx_len);
1989 
1990 // SSL_get0_session_id_context returns a pointer to |ssl|'s session ID context
1991 // and sets |*out_len| to its length.  It returns NULL on error.
1992 OPENSSL_EXPORT const uint8_t *SSL_get0_session_id_context(const SSL *ssl,
1993                                                           size_t *out_len);
1994 
1995 // SSL_SESSION_CACHE_MAX_SIZE_DEFAULT is the default maximum size of a session
1996 // cache.
1997 #define SSL_SESSION_CACHE_MAX_SIZE_DEFAULT (1024 * 20)
1998 
1999 // SSL_CTX_sess_set_cache_size sets the maximum size of |ctx|'s internal session
2000 // cache to |size|. It returns the previous value.
2001 OPENSSL_EXPORT unsigned long SSL_CTX_sess_set_cache_size(SSL_CTX *ctx,
2002                                                          unsigned long size);
2003 
2004 // SSL_CTX_sess_get_cache_size returns the maximum size of |ctx|'s internal
2005 // session cache.
2006 OPENSSL_EXPORT unsigned long SSL_CTX_sess_get_cache_size(const SSL_CTX *ctx);
2007 
2008 // SSL_CTX_sess_number returns the number of sessions in |ctx|'s internal
2009 // session cache.
2010 OPENSSL_EXPORT size_t SSL_CTX_sess_number(const SSL_CTX *ctx);
2011 
2012 // SSL_CTX_add_session inserts |session| into |ctx|'s internal session cache. It
2013 // returns one on success and zero on error or if |session| is already in the
2014 // cache. The caller retains its reference to |session|.
2015 OPENSSL_EXPORT int SSL_CTX_add_session(SSL_CTX *ctx, SSL_SESSION *session);
2016 
2017 // SSL_CTX_remove_session removes |session| from |ctx|'s internal session cache.
2018 // It returns one on success and zero if |session| was not in the cache.
2019 OPENSSL_EXPORT int SSL_CTX_remove_session(SSL_CTX *ctx, SSL_SESSION *session);
2020 
2021 // SSL_CTX_flush_sessions removes all sessions from |ctx| which have expired as
2022 // of time |time|. If |time| is zero, all sessions are removed.
2023 OPENSSL_EXPORT void SSL_CTX_flush_sessions(SSL_CTX *ctx, uint64_t time);
2024 
2025 // SSL_CTX_sess_set_new_cb sets the callback to be called when a new session is
2026 // established and ready to be cached. If the session cache is disabled (the
2027 // appropriate one of |SSL_SESS_CACHE_CLIENT| or |SSL_SESS_CACHE_SERVER| is
2028 // unset), the callback is not called.
2029 //
2030 // The callback is passed a reference to |session|. It returns one if it takes
2031 // ownership (and then calls |SSL_SESSION_free| when done) and zero otherwise. A
2032 // consumer which places |session| into an in-memory cache will likely return
2033 // one, with the cache calling |SSL_SESSION_free|. A consumer which serializes
2034 // |session| with |SSL_SESSION_to_bytes| may not need to retain |session| and
2035 // will likely return zero. Returning one is equivalent to calling
2036 // |SSL_SESSION_up_ref| and then returning zero.
2037 //
2038 // Note: For a client, the callback may be called on abbreviated handshakes if a
2039 // ticket is renewed. Further, it may not be called until some time after
2040 // |SSL_do_handshake| or |SSL_connect| completes if False Start is enabled. Thus
2041 // it's recommended to use this callback over calling |SSL_get_session| on
2042 // handshake completion.
2043 OPENSSL_EXPORT void SSL_CTX_sess_set_new_cb(
2044     SSL_CTX *ctx, int (*new_session_cb)(SSL *ssl, SSL_SESSION *session));
2045 
2046 // SSL_CTX_sess_get_new_cb returns the callback set by
2047 // |SSL_CTX_sess_set_new_cb|.
2048 OPENSSL_EXPORT int (*SSL_CTX_sess_get_new_cb(SSL_CTX *ctx))(
2049     SSL *ssl, SSL_SESSION *session);
2050 
2051 // SSL_CTX_sess_set_remove_cb sets a callback which is called when a session is
2052 // removed from the internal session cache.
2053 //
2054 // TODO(davidben): What is the point of this callback? It seems useless since it
2055 // only fires on sessions in the internal cache.
2056 OPENSSL_EXPORT void SSL_CTX_sess_set_remove_cb(
2057     SSL_CTX *ctx,
2058     void (*remove_session_cb)(SSL_CTX *ctx, SSL_SESSION *session));
2059 
2060 // SSL_CTX_sess_get_remove_cb returns the callback set by
2061 // |SSL_CTX_sess_set_remove_cb|.
2062 OPENSSL_EXPORT void (*SSL_CTX_sess_get_remove_cb(SSL_CTX *ctx))(
2063     SSL_CTX *ctx, SSL_SESSION *session);
2064 
2065 // SSL_CTX_sess_set_get_cb sets a callback to look up a session by ID for a
2066 // server. The callback is passed the session ID and should return a matching
2067 // |SSL_SESSION| or NULL if not found. It should set |*out_copy| to zero and
2068 // return a new reference to the session. This callback is not used for a
2069 // client.
2070 //
2071 // For historical reasons, if |*out_copy| is set to one (default), the SSL
2072 // library will take a new reference to the returned |SSL_SESSION|, expecting
2073 // the callback to return a non-owning pointer. This is not recommended. If
2074 // |ctx| and thus the callback is used on multiple threads, the session may be
2075 // removed and invalidated before the SSL library calls |SSL_SESSION_up_ref|,
2076 // whereas the callback may synchronize internally.
2077 //
2078 // To look up a session asynchronously, the callback may return
2079 // |SSL_magic_pending_session_ptr|. See the documentation for that function and
2080 // |SSL_ERROR_PENDING_SESSION|.
2081 //
2082 // If the internal session cache is enabled, the callback is only consulted if
2083 // the internal cache does not return a match.
2084 OPENSSL_EXPORT void SSL_CTX_sess_set_get_cb(
2085     SSL_CTX *ctx, SSL_SESSION *(*get_session_cb)(SSL *ssl, const uint8_t *id,
2086                                                  int id_len, int *out_copy));
2087 
2088 // SSL_CTX_sess_get_get_cb returns the callback set by
2089 // |SSL_CTX_sess_set_get_cb|.
2090 OPENSSL_EXPORT SSL_SESSION *(*SSL_CTX_sess_get_get_cb(SSL_CTX *ctx))(
2091     SSL *ssl, const uint8_t *id, int id_len, int *out_copy);
2092 
2093 // SSL_magic_pending_session_ptr returns a magic |SSL_SESSION|* which indicates
2094 // that the session isn't currently unavailable. |SSL_get_error| will then
2095 // return |SSL_ERROR_PENDING_SESSION| and the handshake can be retried later
2096 // when the lookup has completed.
2097 OPENSSL_EXPORT SSL_SESSION *SSL_magic_pending_session_ptr(void);
2098 
2099 
2100 // Session tickets.
2101 //
2102 // Session tickets, from RFC 5077, allow session resumption without server-side
2103 // state. The server maintains a secret ticket key and sends the client opaque
2104 // encrypted session parameters, called a ticket. When offering the session, the
2105 // client sends the ticket which the server decrypts to recover session state.
2106 // Session tickets are enabled by default but may be disabled with
2107 // |SSL_OP_NO_TICKET|.
2108 //
2109 // On the client, ticket-based sessions use the same APIs as ID-based tickets.
2110 // Callers do not need to handle them differently.
2111 //
2112 // On the server, tickets are encrypted and authenticated with a secret key.
2113 // By default, an |SSL_CTX| will manage session ticket encryption keys by
2114 // generating them internally and rotating every 48 hours. Tickets are minted
2115 // and processed transparently. The following functions may be used to configure
2116 // a persistent key or implement more custom behavior, including key rotation
2117 // and sharing keys between multiple servers in a large deployment. There are
2118 // three levels of customisation possible:
2119 //
2120 // 1) One can simply set the keys with |SSL_CTX_set_tlsext_ticket_keys|.
2121 // 2) One can configure an |EVP_CIPHER_CTX| and |HMAC_CTX| directly for
2122 //    encryption and authentication.
2123 // 3) One can configure an |SSL_TICKET_AEAD_METHOD| to have more control
2124 //    and the option of asynchronous decryption.
2125 //
2126 // An attacker that compromises a server's session ticket key can impersonate
2127 // the server and, prior to TLS 1.3, retroactively decrypt all application
2128 // traffic from sessions using that ticket key. Thus ticket keys must be
2129 // regularly rotated for forward secrecy. Note the default key is rotated
2130 // automatically once every 48 hours but manually configured keys are not.
2131 
2132 // SSL_DEFAULT_TICKET_KEY_ROTATION_INTERVAL is the interval with which the
2133 // default session ticket encryption key is rotated, if in use. If any
2134 // non-default ticket encryption mechanism is configured, automatic rotation is
2135 // disabled.
2136 #define SSL_DEFAULT_TICKET_KEY_ROTATION_INTERVAL (2 * 24 * 60 * 60)
2137 
2138 // SSL_CTX_get_tlsext_ticket_keys writes |ctx|'s session ticket key material to
2139 // |len| bytes of |out|. It returns one on success and zero if |len| is not
2140 // 48. If |out| is NULL, it returns 48 instead.
2141 OPENSSL_EXPORT int SSL_CTX_get_tlsext_ticket_keys(SSL_CTX *ctx, void *out,
2142                                                   size_t len);
2143 
2144 // SSL_CTX_set_tlsext_ticket_keys sets |ctx|'s session ticket key material to
2145 // |len| bytes of |in|. It returns one on success and zero if |len| is not
2146 // 48. If |in| is NULL, it returns 48 instead.
2147 OPENSSL_EXPORT int SSL_CTX_set_tlsext_ticket_keys(SSL_CTX *ctx, const void *in,
2148                                                   size_t len);
2149 
2150 // SSL_TICKET_KEY_NAME_LEN is the length of the key name prefix of a session
2151 // ticket.
2152 #define SSL_TICKET_KEY_NAME_LEN 16
2153 
2154 // SSL_CTX_set_tlsext_ticket_key_cb sets the ticket callback to |callback| and
2155 // returns one. |callback| will be called when encrypting a new ticket and when
2156 // decrypting a ticket from the client.
2157 //
2158 // In both modes, |ctx| and |hmac_ctx| will already have been initialized with
2159 // |EVP_CIPHER_CTX_init| and |HMAC_CTX_init|, respectively. |callback|
2160 // configures |hmac_ctx| with an HMAC digest and key, and configures |ctx|
2161 // for encryption or decryption, based on the mode.
2162 //
2163 // When encrypting a new ticket, |encrypt| will be one. It writes a public
2164 // 16-byte key name to |key_name| and a fresh IV to |iv|. The output IV length
2165 // must match |EVP_CIPHER_CTX_iv_length| of the cipher selected. In this mode,
2166 // |callback| returns 1 on success and -1 on error.
2167 //
2168 // When decrypting a ticket, |encrypt| will be zero. |key_name| will point to a
2169 // 16-byte key name and |iv| points to an IV. The length of the IV consumed must
2170 // match |EVP_CIPHER_CTX_iv_length| of the cipher selected. In this mode,
2171 // |callback| returns -1 to abort the handshake, 0 if decrypting the ticket
2172 // failed, and 1 or 2 on success. If it returns 2, the ticket will be renewed.
2173 // This may be used to re-key the ticket.
2174 //
2175 // WARNING: |callback| wildly breaks the usual return value convention and is
2176 // called in two different modes.
2177 OPENSSL_EXPORT int SSL_CTX_set_tlsext_ticket_key_cb(
2178     SSL_CTX *ctx, int (*callback)(SSL *ssl, uint8_t *key_name, uint8_t *iv,
2179                                   EVP_CIPHER_CTX *ctx, HMAC_CTX *hmac_ctx,
2180                                   int encrypt));
2181 
2182 // ssl_ticket_aead_result_t enumerates the possible results from decrypting a
2183 // ticket with an |SSL_TICKET_AEAD_METHOD|.
2184 enum ssl_ticket_aead_result_t BORINGSSL_ENUM_INT {
2185   // ssl_ticket_aead_success indicates that the ticket was successfully
2186   // decrypted.
2187   ssl_ticket_aead_success,
2188   // ssl_ticket_aead_retry indicates that the operation could not be
2189   // immediately completed and must be reattempted, via |open|, at a later
2190   // point.
2191   ssl_ticket_aead_retry,
2192   // ssl_ticket_aead_ignore_ticket indicates that the ticket should be ignored
2193   // (i.e. is corrupt or otherwise undecryptable).
2194   ssl_ticket_aead_ignore_ticket,
2195   // ssl_ticket_aead_error indicates that a fatal error occured and the
2196   // handshake should be terminated.
2197   ssl_ticket_aead_error,
2198 };
2199 
2200 // ssl_ticket_aead_method_st (aka |SSL_TICKET_AEAD_METHOD|) contains methods
2201 // for encrypting and decrypting session tickets.
2202 struct ssl_ticket_aead_method_st {
2203   // max_overhead returns the maximum number of bytes of overhead that |seal|
2204   // may add.
2205   size_t (*max_overhead)(SSL *ssl);
2206 
2207   // seal encrypts and authenticates |in_len| bytes from |in|, writes, at most,
2208   // |max_out_len| bytes to |out|, and puts the number of bytes written in
2209   // |*out_len|. The |in| and |out| buffers may be equal but will not otherwise
2210   // alias. It returns one on success or zero on error.
2211   int (*seal)(SSL *ssl, uint8_t *out, size_t *out_len, size_t max_out_len,
2212               const uint8_t *in, size_t in_len);
2213 
2214   // open authenticates and decrypts |in_len| bytes from |in|, writes, at most,
2215   // |max_out_len| bytes of plaintext to |out|, and puts the number of bytes
2216   // written in |*out_len|. The |in| and |out| buffers may be equal but will
2217   // not otherwise alias. See |ssl_ticket_aead_result_t| for details of the
2218   // return values. In the case that a retry is indicated, the caller should
2219   // arrange for the high-level operation on |ssl| to be retried when the
2220   // operation is completed, which will result in another call to |open|.
2221   enum ssl_ticket_aead_result_t (*open)(SSL *ssl, uint8_t *out, size_t *out_len,
2222                                         size_t max_out_len, const uint8_t *in,
2223                                         size_t in_len);
2224 };
2225 
2226 // SSL_CTX_set_ticket_aead_method configures a custom ticket AEAD method table
2227 // on |ctx|. |aead_method| must remain valid for the lifetime of |ctx|.
2228 OPENSSL_EXPORT void SSL_CTX_set_ticket_aead_method(
2229     SSL_CTX *ctx, const SSL_TICKET_AEAD_METHOD *aead_method);
2230 
2231 // SSL_process_tls13_new_session_ticket processes an unencrypted TLS 1.3
2232 // NewSessionTicket message from |buf| and returns a resumable |SSL_SESSION|,
2233 // or NULL on error. The caller takes ownership of the returned session and
2234 // must call |SSL_SESSION_free| to free it.
2235 //
2236 // |buf| contains |buf_len| bytes that represents a complete NewSessionTicket
2237 // message including its header, i.e., one byte for the type (0x04) and three
2238 // bytes for the length. |buf| must contain only one such message.
2239 //
2240 // This function may be used to process NewSessionTicket messages in TLS 1.3
2241 // clients that are handling the record layer externally.
2242 OPENSSL_EXPORT SSL_SESSION *SSL_process_tls13_new_session_ticket(
2243     SSL *ssl, const uint8_t *buf, size_t buf_len);
2244 
2245 
2246 // Elliptic curve Diffie-Hellman.
2247 //
2248 // Cipher suites using an ECDHE key exchange perform Diffie-Hellman over an
2249 // elliptic curve negotiated by both endpoints. See RFC 4492. Only named curves
2250 // are supported. ECDHE is always enabled, but the curve preferences may be
2251 // configured with these functions.
2252 //
2253 // Note that TLS 1.3 renames these from curves to groups. For consistency, we
2254 // currently use the TLS 1.2 name in the API.
2255 
2256 // SSL_CTX_set1_curves sets the preferred curves for |ctx| to be |curves|. Each
2257 // element of |curves| should be a curve nid. It returns one on success and
2258 // zero on failure.
2259 //
2260 // Note that this API uses nid values from nid.h and not the |SSL_CURVE_*|
2261 // values defined below.
2262 OPENSSL_EXPORT int SSL_CTX_set1_curves(SSL_CTX *ctx, const int *curves,
2263                                        size_t curves_len);
2264 
2265 // SSL_set1_curves sets the preferred curves for |ssl| to be |curves|. Each
2266 // element of |curves| should be a curve nid. It returns one on success and
2267 // zero on failure.
2268 //
2269 // Note that this API uses nid values from nid.h and not the |SSL_CURVE_*|
2270 // values defined below.
2271 OPENSSL_EXPORT int SSL_set1_curves(SSL *ssl, const int *curves,
2272                                    size_t curves_len);
2273 
2274 // SSL_CTX_set1_curves_list sets the preferred curves for |ctx| to be the
2275 // colon-separated list |curves|. Each element of |curves| should be a curve
2276 // name (e.g. P-256, X25519, ...). It returns one on success and zero on
2277 // failure.
2278 OPENSSL_EXPORT int SSL_CTX_set1_curves_list(SSL_CTX *ctx, const char *curves);
2279 
2280 // SSL_set1_curves_list sets the preferred curves for |ssl| to be the
2281 // colon-separated list |curves|. Each element of |curves| should be a curve
2282 // name (e.g. P-256, X25519, ...). It returns one on success and zero on
2283 // failure.
2284 OPENSSL_EXPORT int SSL_set1_curves_list(SSL *ssl, const char *curves);
2285 
2286 // SSL_CURVE_* define TLS curve IDs.
2287 #define SSL_CURVE_SECP224R1 21
2288 #define SSL_CURVE_SECP256R1 23
2289 #define SSL_CURVE_SECP384R1 24
2290 #define SSL_CURVE_SECP521R1 25
2291 #define SSL_CURVE_X25519 29
2292 #define SSL_CURVE_CECPQ2 16696
2293 
2294 // SSL_get_curve_id returns the ID of the curve used by |ssl|'s most recently
2295 // completed handshake or 0 if not applicable.
2296 //
2297 // TODO(davidben): This API currently does not work correctly if there is a
2298 // renegotiation in progress. Fix this.
2299 OPENSSL_EXPORT uint16_t SSL_get_curve_id(const SSL *ssl);
2300 
2301 // SSL_get_curve_name returns a human-readable name for the curve specified by
2302 // the given TLS curve id, or NULL if the curve is unknown.
2303 OPENSSL_EXPORT const char *SSL_get_curve_name(uint16_t curve_id);
2304 
2305 
2306 // Certificate verification.
2307 //
2308 // SSL may authenticate either endpoint with an X.509 certificate. Typically
2309 // this is used to authenticate the server to the client. These functions
2310 // configure certificate verification.
2311 //
2312 // WARNING: By default, certificate verification errors on a client are not
2313 // fatal. See |SSL_VERIFY_NONE| This may be configured with
2314 // |SSL_CTX_set_verify|.
2315 //
2316 // By default clients are anonymous but a server may request a certificate from
2317 // the client by setting |SSL_VERIFY_PEER|.
2318 //
2319 // Many of these functions use OpenSSL's legacy X.509 stack which is
2320 // underdocumented and deprecated, but the replacement isn't ready yet. For
2321 // now, consumers may use the existing stack or bypass it by performing
2322 // certificate verification externally. This may be done with
2323 // |SSL_CTX_set_cert_verify_callback| or by extracting the chain with
2324 // |SSL_get_peer_cert_chain| after the handshake. In the future, functions will
2325 // be added to use the SSL stack without dependency on any part of the legacy
2326 // X.509 and ASN.1 stack.
2327 //
2328 // To augment certificate verification, a client may also enable OCSP stapling
2329 // (RFC 6066) and Certificate Transparency (RFC 6962) extensions.
2330 
2331 // SSL_VERIFY_NONE, on a client, verifies the server certificate but does not
2332 // make errors fatal. The result may be checked with |SSL_get_verify_result|. On
2333 // a server it does not request a client certificate. This is the default.
2334 #define SSL_VERIFY_NONE 0x00
2335 
2336 // SSL_VERIFY_PEER, on a client, makes server certificate errors fatal. On a
2337 // server it requests a client certificate and makes errors fatal. However,
2338 // anonymous clients are still allowed. See
2339 // |SSL_VERIFY_FAIL_IF_NO_PEER_CERT|.
2340 #define SSL_VERIFY_PEER 0x01
2341 
2342 // SSL_VERIFY_FAIL_IF_NO_PEER_CERT configures a server to reject connections if
2343 // the client declines to send a certificate. This flag must be used together
2344 // with |SSL_VERIFY_PEER|, otherwise it won't work.
2345 #define SSL_VERIFY_FAIL_IF_NO_PEER_CERT 0x02
2346 
2347 // SSL_VERIFY_PEER_IF_NO_OBC configures a server to request a client certificate
2348 // if and only if Channel ID is not negotiated.
2349 #define SSL_VERIFY_PEER_IF_NO_OBC 0x04
2350 
2351 // SSL_CTX_set_verify configures certificate verification behavior. |mode| is
2352 // one of the |SSL_VERIFY_*| values defined above. |callback|, if not NULL, is
2353 // used to customize certificate verification. See the behavior of
2354 // |X509_STORE_CTX_set_verify_cb|.
2355 //
2356 // The callback may use |SSL_get_ex_data_X509_STORE_CTX_idx| with
2357 // |X509_STORE_CTX_get_ex_data| to look up the |SSL| from |store_ctx|.
2358 OPENSSL_EXPORT void SSL_CTX_set_verify(
2359     SSL_CTX *ctx, int mode, int (*callback)(int ok, X509_STORE_CTX *store_ctx));
2360 
2361 // SSL_set_verify configures certificate verification behavior. |mode| is one of
2362 // the |SSL_VERIFY_*| values defined above. |callback|, if not NULL, is used to
2363 // customize certificate verification. See the behavior of
2364 // |X509_STORE_CTX_set_verify_cb|.
2365 //
2366 // The callback may use |SSL_get_ex_data_X509_STORE_CTX_idx| with
2367 // |X509_STORE_CTX_get_ex_data| to look up the |SSL| from |store_ctx|.
2368 OPENSSL_EXPORT void SSL_set_verify(SSL *ssl, int mode,
2369                                    int (*callback)(int ok,
2370                                                    X509_STORE_CTX *store_ctx));
2371 
2372 enum ssl_verify_result_t BORINGSSL_ENUM_INT {
2373   ssl_verify_ok,
2374   ssl_verify_invalid,
2375   ssl_verify_retry,
2376 };
2377 
2378 // SSL_CTX_set_custom_verify configures certificate verification. |mode| is one
2379 // of the |SSL_VERIFY_*| values defined above. |callback| performs the
2380 // certificate verification.
2381 //
2382 // The callback may call |SSL_get0_peer_certificates| for the certificate chain
2383 // to validate. The callback should return |ssl_verify_ok| if the certificate is
2384 // valid. If the certificate is invalid, the callback should return
2385 // |ssl_verify_invalid| and optionally set |*out_alert| to an alert to send to
2386 // the peer. Some useful alerts include |SSL_AD_CERTIFICATE_EXPIRED|,
2387 // |SSL_AD_CERTIFICATE_REVOKED|, |SSL_AD_UNKNOWN_CA|, |SSL_AD_BAD_CERTIFICATE|,
2388 // |SSL_AD_CERTIFICATE_UNKNOWN|, and |SSL_AD_INTERNAL_ERROR|. See RFC 5246
2389 // section 7.2.2 for their precise meanings. If unspecified,
2390 // |SSL_AD_CERTIFICATE_UNKNOWN| will be sent by default.
2391 //
2392 // To verify a certificate asynchronously, the callback may return
2393 // |ssl_verify_retry|. The handshake will then pause with |SSL_get_error|
2394 // returning |SSL_ERROR_WANT_CERTIFICATE_VERIFY|.
2395 OPENSSL_EXPORT void SSL_CTX_set_custom_verify(
2396     SSL_CTX *ctx, int mode,
2397     enum ssl_verify_result_t (*callback)(SSL *ssl, uint8_t *out_alert));
2398 
2399 // SSL_set_custom_verify behaves like |SSL_CTX_set_custom_verify| but configures
2400 // an individual |SSL|.
2401 OPENSSL_EXPORT void SSL_set_custom_verify(
2402     SSL *ssl, int mode,
2403     enum ssl_verify_result_t (*callback)(SSL *ssl, uint8_t *out_alert));
2404 
2405 // SSL_CTX_get_verify_mode returns |ctx|'s verify mode, set by
2406 // |SSL_CTX_set_verify|.
2407 OPENSSL_EXPORT int SSL_CTX_get_verify_mode(const SSL_CTX *ctx);
2408 
2409 // SSL_get_verify_mode returns |ssl|'s verify mode, set by |SSL_CTX_set_verify|
2410 // or |SSL_set_verify|.  It returns -1 on error.
2411 OPENSSL_EXPORT int SSL_get_verify_mode(const SSL *ssl);
2412 
2413 // SSL_CTX_get_verify_callback returns the callback set by
2414 // |SSL_CTX_set_verify|.
2415 OPENSSL_EXPORT int (*SSL_CTX_get_verify_callback(const SSL_CTX *ctx))(
2416     int ok, X509_STORE_CTX *store_ctx);
2417 
2418 // SSL_get_verify_callback returns the callback set by |SSL_CTX_set_verify| or
2419 // |SSL_set_verify|.
2420 OPENSSL_EXPORT int (*SSL_get_verify_callback(const SSL *ssl))(
2421     int ok, X509_STORE_CTX *store_ctx);
2422 
2423 // SSL_CTX_set_verify_depth sets the maximum depth of a certificate chain
2424 // accepted in verification. This number does not include the leaf, so a depth
2425 // of 1 allows the leaf and one CA certificate.
2426 OPENSSL_EXPORT void SSL_CTX_set_verify_depth(SSL_CTX *ctx, int depth);
2427 
2428 // SSL_set_verify_depth sets the maximum depth of a certificate chain accepted
2429 // in verification. This number does not include the leaf, so a depth of 1
2430 // allows the leaf and one CA certificate.
2431 OPENSSL_EXPORT void SSL_set_verify_depth(SSL *ssl, int depth);
2432 
2433 // SSL_CTX_get_verify_depth returns the maximum depth of a certificate accepted
2434 // in verification.
2435 OPENSSL_EXPORT int SSL_CTX_get_verify_depth(const SSL_CTX *ctx);
2436 
2437 // SSL_get_verify_depth returns the maximum depth of a certificate accepted in
2438 // verification.
2439 OPENSSL_EXPORT int SSL_get_verify_depth(const SSL *ssl);
2440 
2441 // SSL_CTX_set1_param sets verification parameters from |param|. It returns one
2442 // on success and zero on failure. The caller retains ownership of |param|.
2443 OPENSSL_EXPORT int SSL_CTX_set1_param(SSL_CTX *ctx,
2444                                       const X509_VERIFY_PARAM *param);
2445 
2446 // SSL_set1_param sets verification parameters from |param|. It returns one on
2447 // success and zero on failure. The caller retains ownership of |param|.
2448 OPENSSL_EXPORT int SSL_set1_param(SSL *ssl,
2449                                   const X509_VERIFY_PARAM *param);
2450 
2451 // SSL_CTX_get0_param returns |ctx|'s |X509_VERIFY_PARAM| for certificate
2452 // verification. The caller must not release the returned pointer but may call
2453 // functions on it to configure it.
2454 OPENSSL_EXPORT X509_VERIFY_PARAM *SSL_CTX_get0_param(SSL_CTX *ctx);
2455 
2456 // SSL_get0_param returns |ssl|'s |X509_VERIFY_PARAM| for certificate
2457 // verification. The caller must not release the returned pointer but may call
2458 // functions on it to configure it.
2459 OPENSSL_EXPORT X509_VERIFY_PARAM *SSL_get0_param(SSL *ssl);
2460 
2461 // SSL_CTX_set_purpose sets |ctx|'s |X509_VERIFY_PARAM|'s 'purpose' parameter to
2462 // |purpose|. It returns one on success and zero on error.
2463 OPENSSL_EXPORT int SSL_CTX_set_purpose(SSL_CTX *ctx, int purpose);
2464 
2465 // SSL_set_purpose sets |ssl|'s |X509_VERIFY_PARAM|'s 'purpose' parameter to
2466 // |purpose|. It returns one on success and zero on error.
2467 OPENSSL_EXPORT int SSL_set_purpose(SSL *ssl, int purpose);
2468 
2469 // SSL_CTX_set_trust sets |ctx|'s |X509_VERIFY_PARAM|'s 'trust' parameter to
2470 // |trust|. It returns one on success and zero on error.
2471 OPENSSL_EXPORT int SSL_CTX_set_trust(SSL_CTX *ctx, int trust);
2472 
2473 // SSL_set_trust sets |ssl|'s |X509_VERIFY_PARAM|'s 'trust' parameter to
2474 // |trust|. It returns one on success and zero on error.
2475 OPENSSL_EXPORT int SSL_set_trust(SSL *ssl, int trust);
2476 
2477 // SSL_CTX_set_cert_store sets |ctx|'s certificate store to |store|. It takes
2478 // ownership of |store|. The store is used for certificate verification.
2479 //
2480 // The store is also used for the auto-chaining feature, but this is deprecated.
2481 // See also |SSL_MODE_NO_AUTO_CHAIN|.
2482 OPENSSL_EXPORT void SSL_CTX_set_cert_store(SSL_CTX *ctx, X509_STORE *store);
2483 
2484 // SSL_CTX_get_cert_store returns |ctx|'s certificate store.
2485 OPENSSL_EXPORT X509_STORE *SSL_CTX_get_cert_store(const SSL_CTX *ctx);
2486 
2487 // SSL_CTX_set_default_verify_paths loads the OpenSSL system-default trust
2488 // anchors into |ctx|'s store. It returns one on success and zero on failure.
2489 OPENSSL_EXPORT int SSL_CTX_set_default_verify_paths(SSL_CTX *ctx);
2490 
2491 // SSL_CTX_load_verify_locations loads trust anchors into |ctx|'s store from
2492 // |ca_file| and |ca_dir|, either of which may be NULL. If |ca_file| is passed,
2493 // it is opened and PEM-encoded CA certificates are read. If |ca_dir| is passed,
2494 // it is treated as a directory in OpenSSL's hashed directory format. It returns
2495 // one on success and zero on failure.
2496 //
2497 // See
2498 // https://www.openssl.org/docs/man1.1.0/man3/SSL_CTX_load_verify_locations.html
2499 // for documentation on the directory format.
2500 OPENSSL_EXPORT int SSL_CTX_load_verify_locations(SSL_CTX *ctx,
2501                                                  const char *ca_file,
2502                                                  const char *ca_dir);
2503 
2504 // SSL_get_verify_result returns the result of certificate verification. It is
2505 // either |X509_V_OK| or a |X509_V_ERR_*| value.
2506 OPENSSL_EXPORT long SSL_get_verify_result(const SSL *ssl);
2507 
2508 // SSL_alert_from_verify_result returns the SSL alert code, such as
2509 // |SSL_AD_CERTIFICATE_EXPIRED|, that corresponds to an |X509_V_ERR_*| value.
2510 // The return value is always an alert, even when |result| is |X509_V_OK|.
2511 OPENSSL_EXPORT int SSL_alert_from_verify_result(long result);
2512 
2513 // SSL_get_ex_data_X509_STORE_CTX_idx returns the ex_data index used to look up
2514 // the |SSL| associated with an |X509_STORE_CTX| in the verify callback.
2515 OPENSSL_EXPORT int SSL_get_ex_data_X509_STORE_CTX_idx(void);
2516 
2517 // SSL_CTX_set_cert_verify_callback sets a custom callback to be called on
2518 // certificate verification rather than |X509_verify_cert|. |store_ctx| contains
2519 // the verification parameters. The callback should return one on success and
2520 // zero on fatal error. It may use |X509_STORE_CTX_set_error| to set a
2521 // verification result.
2522 //
2523 // The callback may use |SSL_get_ex_data_X509_STORE_CTX_idx| to recover the
2524 // |SSL| object from |store_ctx|.
2525 OPENSSL_EXPORT void SSL_CTX_set_cert_verify_callback(
2526     SSL_CTX *ctx, int (*callback)(X509_STORE_CTX *store_ctx, void *arg),
2527     void *arg);
2528 
2529 // SSL_enable_signed_cert_timestamps causes |ssl| (which must be the client end
2530 // of a connection) to request SCTs from the server. See
2531 // https://tools.ietf.org/html/rfc6962.
2532 //
2533 // Call |SSL_get0_signed_cert_timestamp_list| to recover the SCT after the
2534 // handshake.
2535 OPENSSL_EXPORT void SSL_enable_signed_cert_timestamps(SSL *ssl);
2536 
2537 // SSL_CTX_enable_signed_cert_timestamps enables SCT requests on all client SSL
2538 // objects created from |ctx|.
2539 //
2540 // Call |SSL_get0_signed_cert_timestamp_list| to recover the SCT after the
2541 // handshake.
2542 OPENSSL_EXPORT void SSL_CTX_enable_signed_cert_timestamps(SSL_CTX *ctx);
2543 
2544 // SSL_enable_ocsp_stapling causes |ssl| (which must be the client end of a
2545 // connection) to request a stapled OCSP response from the server.
2546 //
2547 // Call |SSL_get0_ocsp_response| to recover the OCSP response after the
2548 // handshake.
2549 OPENSSL_EXPORT void SSL_enable_ocsp_stapling(SSL *ssl);
2550 
2551 // SSL_CTX_enable_ocsp_stapling enables OCSP stapling on all client SSL objects
2552 // created from |ctx|.
2553 //
2554 // Call |SSL_get0_ocsp_response| to recover the OCSP response after the
2555 // handshake.
2556 OPENSSL_EXPORT void SSL_CTX_enable_ocsp_stapling(SSL_CTX *ctx);
2557 
2558 // SSL_CTX_set0_verify_cert_store sets an |X509_STORE| that will be used
2559 // exclusively for certificate verification and returns one. Ownership of
2560 // |store| is transferred to the |SSL_CTX|.
2561 OPENSSL_EXPORT int SSL_CTX_set0_verify_cert_store(SSL_CTX *ctx,
2562                                                   X509_STORE *store);
2563 
2564 // SSL_CTX_set1_verify_cert_store sets an |X509_STORE| that will be used
2565 // exclusively for certificate verification and returns one. An additional
2566 // reference to |store| will be taken.
2567 OPENSSL_EXPORT int SSL_CTX_set1_verify_cert_store(SSL_CTX *ctx,
2568                                                   X509_STORE *store);
2569 
2570 // SSL_set0_verify_cert_store sets an |X509_STORE| that will be used
2571 // exclusively for certificate verification and returns one. Ownership of
2572 // |store| is transferred to the |SSL|.
2573 OPENSSL_EXPORT int SSL_set0_verify_cert_store(SSL *ssl, X509_STORE *store);
2574 
2575 // SSL_set1_verify_cert_store sets an |X509_STORE| that will be used
2576 // exclusively for certificate verification and returns one. An additional
2577 // reference to |store| will be taken.
2578 OPENSSL_EXPORT int SSL_set1_verify_cert_store(SSL *ssl, X509_STORE *store);
2579 
2580 // SSL_CTX_set_verify_algorithm_prefs configures |ctx| to use |prefs| as the
2581 // preference list when verifying signatures from the peer's long-term key. It
2582 // returns one on zero on error. |prefs| should not include the internal-only
2583 // value |SSL_SIGN_RSA_PKCS1_MD5_SHA1|.
2584 OPENSSL_EXPORT int SSL_CTX_set_verify_algorithm_prefs(SSL_CTX *ctx,
2585                                                       const uint16_t *prefs,
2586                                                       size_t num_prefs);
2587 
2588 // SSL_set_verify_algorithm_prefs configures |ssl| to use |prefs| as the
2589 // preference list when verifying signatures from the peer's long-term key. It
2590 // returns one on zero on error. |prefs| should not include the internal-only
2591 // value |SSL_SIGN_RSA_PKCS1_MD5_SHA1|.
2592 OPENSSL_EXPORT int SSL_set_verify_algorithm_prefs(SSL *ssl,
2593                                                   const uint16_t *prefs,
2594                                                   size_t num_prefs);
2595 
2596 
2597 // Client certificate CA list.
2598 //
2599 // When requesting a client certificate, a server may advertise a list of
2600 // certificate authorities which are accepted. These functions may be used to
2601 // configure this list.
2602 
2603 // SSL_set_client_CA_list sets |ssl|'s client certificate CA list to
2604 // |name_list|. It takes ownership of |name_list|.
2605 OPENSSL_EXPORT void SSL_set_client_CA_list(SSL *ssl,
2606                                            STACK_OF(X509_NAME) *name_list);
2607 
2608 // SSL_CTX_set_client_CA_list sets |ctx|'s client certificate CA list to
2609 // |name_list|. It takes ownership of |name_list|.
2610 OPENSSL_EXPORT void SSL_CTX_set_client_CA_list(SSL_CTX *ctx,
2611                                                STACK_OF(X509_NAME) *name_list);
2612 
2613 // SSL_set0_client_CAs sets |ssl|'s client certificate CA list to |name_list|,
2614 // which should contain DER-encoded distinguished names (RFC 5280). It takes
2615 // ownership of |name_list|.
2616 OPENSSL_EXPORT void SSL_set0_client_CAs(SSL *ssl,
2617                                         STACK_OF(CRYPTO_BUFFER) *name_list);
2618 
2619 // SSL_CTX_set0_client_CAs sets |ctx|'s client certificate CA list to
2620 // |name_list|, which should contain DER-encoded distinguished names (RFC 5280).
2621 // It takes ownership of |name_list|.
2622 OPENSSL_EXPORT void SSL_CTX_set0_client_CAs(SSL_CTX *ctx,
2623                                             STACK_OF(CRYPTO_BUFFER) *name_list);
2624 
2625 // SSL_get_client_CA_list returns |ssl|'s client certificate CA list. If |ssl|
2626 // has not been configured as a client, this is the list configured by
2627 // |SSL_CTX_set_client_CA_list|.
2628 //
2629 // If configured as a client, it returns the client certificate CA list sent by
2630 // the server. In this mode, the behavior is undefined except during the
2631 // callbacks set by |SSL_CTX_set_cert_cb| and |SSL_CTX_set_client_cert_cb| or
2632 // when the handshake is paused because of them.
2633 OPENSSL_EXPORT STACK_OF(X509_NAME) *SSL_get_client_CA_list(const SSL *ssl);
2634 
2635 // SSL_get0_server_requested_CAs returns the CAs sent by a server to guide a
2636 // client in certificate selection. They are a series of DER-encoded X.509
2637 // names. This function may only be called during a callback set by
2638 // |SSL_CTX_set_cert_cb| or when the handshake is paused because of it.
2639 //
2640 // The returned stack is owned by |ssl|, as are its contents. It should not be
2641 // used past the point where the handshake is restarted after the callback.
2642 OPENSSL_EXPORT const STACK_OF(CRYPTO_BUFFER) *
2643     SSL_get0_server_requested_CAs(const SSL *ssl);
2644 
2645 // SSL_CTX_get_client_CA_list returns |ctx|'s client certificate CA list.
2646 OPENSSL_EXPORT STACK_OF(X509_NAME) *
2647     SSL_CTX_get_client_CA_list(const SSL_CTX *ctx);
2648 
2649 // SSL_add_client_CA appends |x509|'s subject to the client certificate CA list.
2650 // It returns one on success or zero on error. The caller retains ownership of
2651 // |x509|.
2652 OPENSSL_EXPORT int SSL_add_client_CA(SSL *ssl, X509 *x509);
2653 
2654 // SSL_CTX_add_client_CA appends |x509|'s subject to the client certificate CA
2655 // list. It returns one on success or zero on error. The caller retains
2656 // ownership of |x509|.
2657 OPENSSL_EXPORT int SSL_CTX_add_client_CA(SSL_CTX *ctx, X509 *x509);
2658 
2659 // SSL_load_client_CA_file opens |file| and reads PEM-encoded certificates from
2660 // it. It returns a newly-allocated stack of the certificate subjects or NULL
2661 // on error.
2662 OPENSSL_EXPORT STACK_OF(X509_NAME) *SSL_load_client_CA_file(const char *file);
2663 
2664 // SSL_dup_CA_list makes a deep copy of |list|. It returns the new list on
2665 // success or NULL on allocation error.
2666 OPENSSL_EXPORT STACK_OF(X509_NAME) *SSL_dup_CA_list(STACK_OF(X509_NAME) *list);
2667 
2668 // SSL_add_file_cert_subjects_to_stack behaves like |SSL_load_client_CA_file|
2669 // but appends the result to |out|. It returns one on success or zero on
2670 // error.
2671 OPENSSL_EXPORT int SSL_add_file_cert_subjects_to_stack(STACK_OF(X509_NAME) *out,
2672                                                        const char *file);
2673 
2674 
2675 // Server name indication.
2676 //
2677 // The server_name extension (RFC 3546) allows the client to advertise the name
2678 // of the server it is connecting to. This is used in virtual hosting
2679 // deployments to select one of a several certificates on a single IP. Only the
2680 // host_name name type is supported.
2681 
2682 #define TLSEXT_NAMETYPE_host_name 0
2683 
2684 // SSL_set_tlsext_host_name, for a client, configures |ssl| to advertise |name|
2685 // in the server_name extension. It returns one on success and zero on error.
2686 OPENSSL_EXPORT int SSL_set_tlsext_host_name(SSL *ssl, const char *name);
2687 
2688 // SSL_get_servername, for a server, returns the hostname supplied by the
2689 // client or NULL if there was none. The |type| argument must be
2690 // |TLSEXT_NAMETYPE_host_name|.
2691 OPENSSL_EXPORT const char *SSL_get_servername(const SSL *ssl, const int type);
2692 
2693 // SSL_get_servername_type, for a server, returns |TLSEXT_NAMETYPE_host_name|
2694 // if the client sent a hostname and -1 otherwise.
2695 OPENSSL_EXPORT int SSL_get_servername_type(const SSL *ssl);
2696 
2697 // SSL_CTX_set_tlsext_servername_callback configures |callback| to be called on
2698 // the server after ClientHello extensions have been parsed and returns one.
2699 // The callback may use |SSL_get_servername| to examine the server_name
2700 // extension and returns a |SSL_TLSEXT_ERR_*| value. The value of |arg| may be
2701 // set by calling |SSL_CTX_set_tlsext_servername_arg|.
2702 //
2703 // If the callback returns |SSL_TLSEXT_ERR_NOACK|, the server_name extension is
2704 // not acknowledged in the ServerHello. If the return value is
2705 // |SSL_TLSEXT_ERR_ALERT_FATAL|, then |*out_alert| is the alert to send,
2706 // defaulting to |SSL_AD_UNRECOGNIZED_NAME|. |SSL_TLSEXT_ERR_ALERT_WARNING| is
2707 // ignored and treated as |SSL_TLSEXT_ERR_OK|.
2708 OPENSSL_EXPORT int SSL_CTX_set_tlsext_servername_callback(
2709     SSL_CTX *ctx, int (*callback)(SSL *ssl, int *out_alert, void *arg));
2710 
2711 // SSL_CTX_set_tlsext_servername_arg sets the argument to the servername
2712 // callback and returns one. See |SSL_CTX_set_tlsext_servername_callback|.
2713 OPENSSL_EXPORT int SSL_CTX_set_tlsext_servername_arg(SSL_CTX *ctx, void *arg);
2714 
2715 // SSL_TLSEXT_ERR_* are values returned by some extension-related callbacks.
2716 #define SSL_TLSEXT_ERR_OK 0
2717 #define SSL_TLSEXT_ERR_ALERT_WARNING 1
2718 #define SSL_TLSEXT_ERR_ALERT_FATAL 2
2719 #define SSL_TLSEXT_ERR_NOACK 3
2720 
2721 // SSL_set_SSL_CTX changes |ssl|'s |SSL_CTX|. |ssl| will use the
2722 // certificate-related settings from |ctx|, and |SSL_get_SSL_CTX| will report
2723 // |ctx|. This function may be used during the callbacks registered by
2724 // |SSL_CTX_set_select_certificate_cb|,
2725 // |SSL_CTX_set_tlsext_servername_callback|, and |SSL_CTX_set_cert_cb| or when
2726 // the handshake is paused from them. It is typically used to switch
2727 // certificates based on SNI.
2728 //
2729 // Note the session cache and related settings will continue to use the initial
2730 // |SSL_CTX|. Callers should use |SSL_CTX_set_session_id_context| to partition
2731 // the session cache between different domains.
2732 //
2733 // TODO(davidben): Should other settings change after this call?
2734 OPENSSL_EXPORT SSL_CTX *SSL_set_SSL_CTX(SSL *ssl, SSL_CTX *ctx);
2735 
2736 
2737 // Application-layer protocol negotiation.
2738 //
2739 // The ALPN extension (RFC 7301) allows negotiating different application-layer
2740 // protocols over a single port. This is used, for example, to negotiate
2741 // HTTP/2.
2742 
2743 // SSL_CTX_set_alpn_protos sets the client ALPN protocol list on |ctx| to
2744 // |protos|. |protos| must be in wire-format (i.e. a series of non-empty, 8-bit
2745 // length-prefixed strings), or the empty string to disable ALPN. It returns
2746 // zero on success and one on failure. Configuring a non-empty string enables
2747 // ALPN on a client.
2748 //
2749 // WARNING: this function is dangerous because it breaks the usual return value
2750 // convention.
2751 OPENSSL_EXPORT int SSL_CTX_set_alpn_protos(SSL_CTX *ctx, const uint8_t *protos,
2752                                            unsigned protos_len);
2753 
2754 // SSL_set_alpn_protos sets the client ALPN protocol list on |ssl| to |protos|.
2755 // |protos| must be in wire-format (i.e. a series of non-empty, 8-bit
2756 // length-prefixed strings), or the empty string to disable ALPN. It returns
2757 // zero on success and one on failure. Configuring a non-empty string enables
2758 // ALPN on a client.
2759 //
2760 // WARNING: this function is dangerous because it breaks the usual return value
2761 // convention.
2762 OPENSSL_EXPORT int SSL_set_alpn_protos(SSL *ssl, const uint8_t *protos,
2763                                        unsigned protos_len);
2764 
2765 // SSL_CTX_set_alpn_select_cb sets a callback function on |ctx| that is called
2766 // during ClientHello processing in order to select an ALPN protocol from the
2767 // client's list of offered protocols.
2768 //
2769 // The callback is passed a wire-format (i.e. a series of non-empty, 8-bit
2770 // length-prefixed strings) ALPN protocol list in |in|. To select a protocol,
2771 // the callback should set |*out| and |*out_len| to the selected protocol and
2772 // return |SSL_TLSEXT_ERR_OK| on success. It does not pass ownership of the
2773 // buffer, so |*out| should point to a static string, a buffer that outlives the
2774 // callback call, or the corresponding entry in |in|.
2775 //
2776 // If the server supports ALPN, but there are no protocols in common, the
2777 // callback should return |SSL_TLSEXT_ERR_ALERT_FATAL| to abort the connection
2778 // with a no_application_protocol alert.
2779 //
2780 // If the server does not support ALPN, it can return |SSL_TLSEXT_ERR_NOACK| to
2781 // continue the handshake without negotiating a protocol. This may be useful if
2782 // multiple server configurations share an |SSL_CTX|, only some of which have
2783 // ALPN protocols configured.
2784 //
2785 // |SSL_TLSEXT_ERR_ALERT_WARNING| is ignored and will be treated as
2786 // |SSL_TLSEXT_ERR_NOACK|.
2787 //
2788 // The callback will only be called if the client supports ALPN. Callers that
2789 // wish to require ALPN for all clients must check |SSL_get0_alpn_selected|
2790 // after the handshake. In QUIC connections, this is done automatically.
2791 //
2792 // The cipher suite is selected before negotiating ALPN. The callback may use
2793 // |SSL_get_pending_cipher| to query the cipher suite. This may be used to
2794 // implement HTTP/2's cipher suite constraints.
2795 OPENSSL_EXPORT void SSL_CTX_set_alpn_select_cb(
2796     SSL_CTX *ctx, int (*cb)(SSL *ssl, const uint8_t **out, uint8_t *out_len,
2797                             const uint8_t *in, unsigned in_len, void *arg),
2798     void *arg);
2799 
2800 // SSL_get0_alpn_selected gets the selected ALPN protocol (if any) from |ssl|.
2801 // On return it sets |*out_data| to point to |*out_len| bytes of protocol name
2802 // (not including the leading length-prefix byte). If the server didn't respond
2803 // with a negotiated protocol then |*out_len| will be zero.
2804 OPENSSL_EXPORT void SSL_get0_alpn_selected(const SSL *ssl,
2805                                            const uint8_t **out_data,
2806                                            unsigned *out_len);
2807 
2808 // SSL_CTX_set_allow_unknown_alpn_protos configures client connections on |ctx|
2809 // to allow unknown ALPN protocols from the server. Otherwise, by default, the
2810 // client will require that the protocol be advertised in
2811 // |SSL_CTX_set_alpn_protos|.
2812 OPENSSL_EXPORT void SSL_CTX_set_allow_unknown_alpn_protos(SSL_CTX *ctx,
2813                                                           int enabled);
2814 
2815 
2816 // Application-layer protocol settings
2817 //
2818 // The ALPS extension (draft-vvv-tls-alps) allows exchanging application-layer
2819 // settings in the TLS handshake for applications negotiated with ALPN. Note
2820 // that, when ALPS is negotiated, the client and server each advertise their own
2821 // settings, so there are functions to both configure setting to send and query
2822 // received settings.
2823 
2824 // SSL_add_application_settings configures |ssl| to enable ALPS with ALPN
2825 // protocol |proto|, sending an ALPS value of |settings|. It returns one on
2826 // success and zero on error. If |proto| is negotiated via ALPN and the peer
2827 // supports ALPS, |settings| will be sent to the peer. The peer's ALPS value can
2828 // be retrieved with |SSL_get0_peer_application_settings|.
2829 //
2830 // On the client, this function should be called before the handshake, once for
2831 // each supported ALPN protocol which uses ALPS. |proto| must be included in the
2832 // client's ALPN configuration (see |SSL_CTX_set_alpn_protos| and
2833 // |SSL_set_alpn_protos|). On the server, ALPS can be preconfigured for each
2834 // protocol as in the client, or configuration can be deferred to the ALPN
2835 // callback (see |SSL_CTX_set_alpn_select_cb|), in which case only the selected
2836 // protocol needs to be configured.
2837 //
2838 // ALPS can be independently configured from 0-RTT, however changes in protocol
2839 // settings will fallback to 1-RTT to negotiate the new value, so it is
2840 // recommended for |settings| to be relatively stable.
2841 OPENSSL_EXPORT int SSL_add_application_settings(SSL *ssl, const uint8_t *proto,
2842                                                 size_t proto_len,
2843                                                 const uint8_t *settings,
2844                                                 size_t settings_len);
2845 
2846 // SSL_get0_peer_application_settings sets |*out_data| and |*out_len| to a
2847 // buffer containing the peer's ALPS value, or the empty string if ALPS was not
2848 // negotiated. Note an empty string could also indicate the peer sent an empty
2849 // settings value. Use |SSL_has_application_settings| to check if ALPS was
2850 // negotiated. The output buffer is owned by |ssl| and is valid until the next
2851 // time |ssl| is modified.
2852 OPENSSL_EXPORT void SSL_get0_peer_application_settings(const SSL *ssl,
2853                                                        const uint8_t **out_data,
2854                                                        size_t *out_len);
2855 
2856 // SSL_has_application_settings returns one if ALPS was negotiated on this
2857 // connection and zero otherwise.
2858 OPENSSL_EXPORT int SSL_has_application_settings(const SSL *ssl);
2859 
2860 
2861 // Certificate compression.
2862 //
2863 // Certificates in TLS 1.3 can be compressed (RFC 8879). BoringSSL supports this
2864 // as both a client and a server, but does not link against any specific
2865 // compression libraries in order to keep dependencies to a minimum. Instead,
2866 // hooks for compression and decompression can be installed in an |SSL_CTX| to
2867 // enable support.
2868 
2869 // ssl_cert_compression_func_t is a pointer to a function that performs
2870 // compression. It must write the compressed representation of |in| to |out|,
2871 // returning one on success and zero on error. The results of compressing
2872 // certificates are not cached internally. Implementations may wish to implement
2873 // their own cache if they expect it to be useful given the certificates that
2874 // they serve.
2875 typedef int (*ssl_cert_compression_func_t)(SSL *ssl, CBB *out,
2876                                            const uint8_t *in, size_t in_len);
2877 
2878 // ssl_cert_decompression_func_t is a pointer to a function that performs
2879 // decompression. The compressed data from the peer is passed as |in| and the
2880 // decompressed result must be exactly |uncompressed_len| bytes long. It returns
2881 // one on success, in which case |*out| must be set to the result of
2882 // decompressing |in|, or zero on error. Setting |*out| transfers ownership,
2883 // i.e. |CRYPTO_BUFFER_free| will be called on |*out| at some point in the
2884 // future. The results of decompressions are not cached internally.
2885 // Implementations may wish to implement their own cache if they expect it to be
2886 // useful.
2887 typedef int (*ssl_cert_decompression_func_t)(SSL *ssl, CRYPTO_BUFFER **out,
2888                                              size_t uncompressed_len,
2889                                              const uint8_t *in, size_t in_len);
2890 
2891 // SSL_CTX_add_cert_compression_alg registers a certificate compression
2892 // algorithm on |ctx| with ID |alg_id|. (The value of |alg_id| should be an IANA
2893 // assigned value and each can only be registered once.)
2894 //
2895 // One of the function pointers may be NULL to avoid having to implement both
2896 // sides of a compression algorithm if you're only going to use it in one
2897 // direction. In this case, the unimplemented direction acts like it was never
2898 // configured.
2899 //
2900 // For a server, algorithms are registered in preference order with the most
2901 // preferable first. It returns one on success or zero on error.
2902 OPENSSL_EXPORT int SSL_CTX_add_cert_compression_alg(
2903     SSL_CTX *ctx, uint16_t alg_id, ssl_cert_compression_func_t compress,
2904     ssl_cert_decompression_func_t decompress);
2905 
2906 
2907 // Next protocol negotiation.
2908 //
2909 // The NPN extension (draft-agl-tls-nextprotoneg-03) is the predecessor to ALPN
2910 // and deprecated in favor of it.
2911 
2912 // SSL_CTX_set_next_protos_advertised_cb sets a callback that is called when a
2913 // TLS server needs a list of supported protocols for Next Protocol
2914 // Negotiation. The returned list must be in wire format. The list is returned
2915 // by setting |*out| to point to it and |*out_len| to its length. This memory
2916 // will not be modified, but one should assume that |ssl| keeps a reference to
2917 // it.
2918 //
2919 // The callback should return |SSL_TLSEXT_ERR_OK| if it wishes to advertise.
2920 // Otherwise, no such extension will be included in the ServerHello.
2921 OPENSSL_EXPORT void SSL_CTX_set_next_protos_advertised_cb(
2922     SSL_CTX *ctx,
2923     int (*cb)(SSL *ssl, const uint8_t **out, unsigned *out_len, void *arg),
2924     void *arg);
2925 
2926 // SSL_CTX_set_next_proto_select_cb sets a callback that is called when a client
2927 // needs to select a protocol from the server's provided list. |*out| must be
2928 // set to point to the selected protocol (which may be within |in|). The length
2929 // of the protocol name must be written into |*out_len|. The server's advertised
2930 // protocols are provided in |in| and |in_len|. The callback can assume that
2931 // |in| is syntactically valid.
2932 //
2933 // The client must select a protocol. It is fatal to the connection if this
2934 // callback returns a value other than |SSL_TLSEXT_ERR_OK|.
2935 //
2936 // Configuring this callback enables NPN on a client.
2937 OPENSSL_EXPORT void SSL_CTX_set_next_proto_select_cb(
2938     SSL_CTX *ctx, int (*cb)(SSL *ssl, uint8_t **out, uint8_t *out_len,
2939                             const uint8_t *in, unsigned in_len, void *arg),
2940     void *arg);
2941 
2942 // SSL_get0_next_proto_negotiated sets |*out_data| and |*out_len| to point to
2943 // the client's requested protocol for this connection. If the client didn't
2944 // request any protocol, then |*out_data| is set to NULL.
2945 //
2946 // Note that the client can request any protocol it chooses. The value returned
2947 // from this function need not be a member of the list of supported protocols
2948 // provided by the server.
2949 OPENSSL_EXPORT void SSL_get0_next_proto_negotiated(const SSL *ssl,
2950                                                    const uint8_t **out_data,
2951                                                    unsigned *out_len);
2952 
2953 // SSL_select_next_proto implements the standard protocol selection. It is
2954 // expected that this function is called from the callback set by
2955 // |SSL_CTX_set_next_proto_select_cb|.
2956 //
2957 // |peer| and |supported| must be vectors of 8-bit, length-prefixed byte strings
2958 // containing the peer and locally-configured protocols, respectively. The
2959 // length byte itself is not included in the length. A byte string of length 0
2960 // is invalid. No byte string may be truncated. |supported| is assumed to be
2961 // non-empty.
2962 //
2963 // This function finds the first protocol in |peer| which is also in
2964 // |supported|. If one was found, it sets |*out| and |*out_len| to point to it
2965 // and returns |OPENSSL_NPN_NEGOTIATED|. Otherwise, it returns
2966 // |OPENSSL_NPN_NO_OVERLAP| and sets |*out| and |*out_len| to the first
2967 // supported protocol.
2968 OPENSSL_EXPORT int SSL_select_next_proto(uint8_t **out, uint8_t *out_len,
2969                                          const uint8_t *peer, unsigned peer_len,
2970                                          const uint8_t *supported,
2971                                          unsigned supported_len);
2972 
2973 #define OPENSSL_NPN_UNSUPPORTED 0
2974 #define OPENSSL_NPN_NEGOTIATED 1
2975 #define OPENSSL_NPN_NO_OVERLAP 2
2976 
2977 
2978 // Channel ID.
2979 //
2980 // See draft-balfanz-tls-channelid-01. This is an old, experimental mechanism
2981 // and should not be used in new code.
2982 
2983 // SSL_CTX_set_tls_channel_id_enabled configures whether connections associated
2984 // with |ctx| should enable Channel ID as a server.
2985 OPENSSL_EXPORT void SSL_CTX_set_tls_channel_id_enabled(SSL_CTX *ctx,
2986                                                        int enabled);
2987 
2988 // SSL_set_tls_channel_id_enabled configures whether |ssl| should enable Channel
2989 // ID as a server.
2990 OPENSSL_EXPORT void SSL_set_tls_channel_id_enabled(SSL *ssl, int enabled);
2991 
2992 // SSL_CTX_set1_tls_channel_id configures a TLS client to send a TLS Channel ID
2993 // to compatible servers. |private_key| must be a P-256 EC key. It returns one
2994 // on success and zero on error.
2995 OPENSSL_EXPORT int SSL_CTX_set1_tls_channel_id(SSL_CTX *ctx,
2996                                                EVP_PKEY *private_key);
2997 
2998 // SSL_set1_tls_channel_id configures a TLS client to send a TLS Channel ID to
2999 // compatible servers. |private_key| must be a P-256 EC key. It returns one on
3000 // success and zero on error.
3001 OPENSSL_EXPORT int SSL_set1_tls_channel_id(SSL *ssl, EVP_PKEY *private_key);
3002 
3003 // SSL_get_tls_channel_id gets the client's TLS Channel ID from a server |SSL|
3004 // and copies up to the first |max_out| bytes into |out|. The Channel ID
3005 // consists of the client's P-256 public key as an (x,y) pair where each is a
3006 // 32-byte, big-endian field element. It returns 0 if the client didn't offer a
3007 // Channel ID and the length of the complete Channel ID otherwise. This function
3008 // always returns zero if |ssl| is a client.
3009 OPENSSL_EXPORT size_t SSL_get_tls_channel_id(SSL *ssl, uint8_t *out,
3010                                              size_t max_out);
3011 
3012 
3013 // DTLS-SRTP.
3014 //
3015 // See RFC 5764.
3016 
3017 // srtp_protection_profile_st (aka |SRTP_PROTECTION_PROFILE|) is an SRTP
3018 // profile for use with the use_srtp extension.
3019 struct srtp_protection_profile_st {
3020   const char *name;
3021   unsigned long id;
3022 } /* SRTP_PROTECTION_PROFILE */;
3023 
3024 DEFINE_CONST_STACK_OF(SRTP_PROTECTION_PROFILE)
3025 
3026 // SRTP_* define constants for SRTP profiles.
3027 #define SRTP_AES128_CM_SHA1_80 0x0001
3028 #define SRTP_AES128_CM_SHA1_32 0x0002
3029 #define SRTP_AES128_F8_SHA1_80 0x0003
3030 #define SRTP_AES128_F8_SHA1_32 0x0004
3031 #define SRTP_NULL_SHA1_80      0x0005
3032 #define SRTP_NULL_SHA1_32      0x0006
3033 #define SRTP_AEAD_AES_128_GCM  0x0007
3034 #define SRTP_AEAD_AES_256_GCM  0x0008
3035 
3036 // SSL_CTX_set_srtp_profiles enables SRTP for all SSL objects created from
3037 // |ctx|. |profile| contains a colon-separated list of profile names. It returns
3038 // one on success and zero on failure.
3039 OPENSSL_EXPORT int SSL_CTX_set_srtp_profiles(SSL_CTX *ctx,
3040                                              const char *profiles);
3041 
3042 // SSL_set_srtp_profiles enables SRTP for |ssl|.  |profile| contains a
3043 // colon-separated list of profile names. It returns one on success and zero on
3044 // failure.
3045 OPENSSL_EXPORT int SSL_set_srtp_profiles(SSL *ssl, const char *profiles);
3046 
3047 // SSL_get_srtp_profiles returns the SRTP profiles supported by |ssl|.
3048 OPENSSL_EXPORT const STACK_OF(SRTP_PROTECTION_PROFILE) *SSL_get_srtp_profiles(
3049     const SSL *ssl);
3050 
3051 // SSL_get_selected_srtp_profile returns the selected SRTP profile, or NULL if
3052 // SRTP was not negotiated.
3053 OPENSSL_EXPORT const SRTP_PROTECTION_PROFILE *SSL_get_selected_srtp_profile(
3054     SSL *ssl);
3055 
3056 
3057 // Pre-shared keys.
3058 //
3059 // Connections may be configured with PSK (Pre-Shared Key) cipher suites. These
3060 // authenticate using out-of-band pre-shared keys rather than certificates. See
3061 // RFC 4279.
3062 //
3063 // This implementation uses NUL-terminated C strings for identities and identity
3064 // hints, so values with a NUL character are not supported. (RFC 4279 does not
3065 // specify the format of an identity.)
3066 
3067 // PSK_MAX_IDENTITY_LEN is the maximum supported length of a PSK identity,
3068 // excluding the NUL terminator.
3069 #define PSK_MAX_IDENTITY_LEN 128
3070 
3071 // PSK_MAX_PSK_LEN is the maximum supported length of a pre-shared key.
3072 #define PSK_MAX_PSK_LEN 256
3073 
3074 // SSL_CTX_set_psk_client_callback sets the callback to be called when PSK is
3075 // negotiated on the client. This callback must be set to enable PSK cipher
3076 // suites on the client.
3077 //
3078 // The callback is passed the identity hint in |hint| or NULL if none was
3079 // provided. It should select a PSK identity and write the identity and the
3080 // corresponding PSK to |identity| and |psk|, respectively. The identity is
3081 // written as a NUL-terminated C string of length (excluding the NUL terminator)
3082 // at most |max_identity_len|. The PSK's length must be at most |max_psk_len|.
3083 // The callback returns the length of the PSK or 0 if no suitable identity was
3084 // found.
3085 OPENSSL_EXPORT void SSL_CTX_set_psk_client_callback(
3086     SSL_CTX *ctx, unsigned (*cb)(SSL *ssl, const char *hint, char *identity,
3087                                  unsigned max_identity_len, uint8_t *psk,
3088                                  unsigned max_psk_len));
3089 
3090 // SSL_set_psk_client_callback sets the callback to be called when PSK is
3091 // negotiated on the client. This callback must be set to enable PSK cipher
3092 // suites on the client. See also |SSL_CTX_set_psk_client_callback|.
3093 OPENSSL_EXPORT void SSL_set_psk_client_callback(
3094     SSL *ssl, unsigned (*cb)(SSL *ssl, const char *hint, char *identity,
3095                              unsigned max_identity_len, uint8_t *psk,
3096                              unsigned max_psk_len));
3097 
3098 // SSL_CTX_set_psk_server_callback sets the callback to be called when PSK is
3099 // negotiated on the server. This callback must be set to enable PSK cipher
3100 // suites on the server.
3101 //
3102 // The callback is passed the identity in |identity|. It should write a PSK of
3103 // length at most |max_psk_len| to |psk| and return the number of bytes written
3104 // or zero if the PSK identity is unknown.
3105 OPENSSL_EXPORT void SSL_CTX_set_psk_server_callback(
3106     SSL_CTX *ctx, unsigned (*cb)(SSL *ssl, const char *identity, uint8_t *psk,
3107                                  unsigned max_psk_len));
3108 
3109 // SSL_set_psk_server_callback sets the callback to be called when PSK is
3110 // negotiated on the server. This callback must be set to enable PSK cipher
3111 // suites on the server. See also |SSL_CTX_set_psk_server_callback|.
3112 OPENSSL_EXPORT void SSL_set_psk_server_callback(
3113     SSL *ssl, unsigned (*cb)(SSL *ssl, const char *identity, uint8_t *psk,
3114                              unsigned max_psk_len));
3115 
3116 // SSL_CTX_use_psk_identity_hint configures server connections to advertise an
3117 // identity hint of |identity_hint|. It returns one on success and zero on
3118 // error.
3119 OPENSSL_EXPORT int SSL_CTX_use_psk_identity_hint(SSL_CTX *ctx,
3120                                                  const char *identity_hint);
3121 
3122 // SSL_use_psk_identity_hint configures server connections to advertise an
3123 // identity hint of |identity_hint|. It returns one on success and zero on
3124 // error.
3125 OPENSSL_EXPORT int SSL_use_psk_identity_hint(SSL *ssl,
3126                                              const char *identity_hint);
3127 
3128 // SSL_get_psk_identity_hint returns the PSK identity hint advertised for |ssl|
3129 // or NULL if there is none.
3130 OPENSSL_EXPORT const char *SSL_get_psk_identity_hint(const SSL *ssl);
3131 
3132 // SSL_get_psk_identity, after the handshake completes, returns the PSK identity
3133 // that was negotiated by |ssl| or NULL if PSK was not used.
3134 OPENSSL_EXPORT const char *SSL_get_psk_identity(const SSL *ssl);
3135 
3136 
3137 // Delegated credentials.
3138 //
3139 // *** EXPERIMENTAL — PRONE TO CHANGE ***
3140 //
3141 // draft-ietf-tls-subcerts is a proposed extension for TLS 1.3 and above that
3142 // allows an end point to use its certificate to delegate credentials for
3143 // authentication. If the peer indicates support for this extension, then this
3144 // host may use a delegated credential to sign the handshake. Once issued,
3145 // credentials can't be revoked. In order to mitigate the damage in case the
3146 // credential secret key is compromised, the credential is only valid for a
3147 // short time (days, hours, or even minutes). This library implements draft-03
3148 // of the protocol spec.
3149 //
3150 // The extension ID has not been assigned; we're using 0xff02 for the time
3151 // being. Currently only the server side is implemented.
3152 //
3153 // Servers configure a DC for use in the handshake via
3154 // |SSL_set1_delegated_credential|. It must be signed by the host's end-entity
3155 // certificate as defined in draft-ietf-tls-subcerts-03.
3156 
3157 // SSL_set1_delegated_credential configures the delegated credential (DC) that
3158 // will be sent to the peer for the current connection. |dc| is the DC in wire
3159 // format, and |pkey| or |key_method| is the corresponding private key.
3160 // Currently (as of draft-03), only servers may configure a DC to use in the
3161 // handshake.
3162 //
3163 // The DC will only be used if the protocol version is correct and the signature
3164 // scheme is supported by the peer. If not, the DC will not be negotiated and
3165 // the handshake will use the private key (or private key method) associated
3166 // with the certificate.
3167 OPENSSL_EXPORT int SSL_set1_delegated_credential(
3168     SSL *ssl, CRYPTO_BUFFER *dc, EVP_PKEY *pkey,
3169     const SSL_PRIVATE_KEY_METHOD *key_method);
3170 
3171 // SSL_delegated_credential_used returns one if a delegated credential was used
3172 // and zero otherwise.
3173 OPENSSL_EXPORT int SSL_delegated_credential_used(const SSL *ssl);
3174 
3175 
3176 // QUIC integration.
3177 //
3178 // QUIC acts as an underlying transport for the TLS 1.3 handshake. The following
3179 // functions allow a QUIC implementation to serve as the underlying transport as
3180 // described in RFC 9001.
3181 //
3182 // When configured for QUIC, |SSL_do_handshake| will drive the handshake as
3183 // before, but it will not use the configured |BIO|. It will call functions on
3184 // |SSL_QUIC_METHOD| to configure secrets and send data. If data is needed from
3185 // the peer, it will return |SSL_ERROR_WANT_READ|. As the caller receives data
3186 // it can decrypt, it calls |SSL_provide_quic_data|. Subsequent
3187 // |SSL_do_handshake| calls will then consume that data and progress the
3188 // handshake. After the handshake is complete, the caller should continue to
3189 // call |SSL_provide_quic_data| for any post-handshake data, followed by
3190 // |SSL_process_quic_post_handshake| to process it. It is an error to call
3191 // |SSL_read| and |SSL_write| in QUIC.
3192 //
3193 // 0-RTT behaves similarly to |TLS_method|'s usual behavior. |SSL_do_handshake|
3194 // returns early as soon as the client (respectively, server) is allowed to send
3195 // 0-RTT (respectively, half-RTT) data. The caller should then call
3196 // |SSL_do_handshake| again to consume the remaining handshake messages and
3197 // confirm the handshake. As a client, |SSL_ERROR_EARLY_DATA_REJECTED| and
3198 // |SSL_reset_early_data_reject| behave as usual.
3199 //
3200 // See https://www.rfc-editor.org/rfc/rfc9001.html#section-4.1 for more details.
3201 //
3202 // To avoid DoS attacks, the QUIC implementation must limit the amount of data
3203 // being queued up. The implementation can call
3204 // |SSL_quic_max_handshake_flight_len| to get the maximum buffer length at each
3205 // encryption level.
3206 //
3207 // QUIC implementations must additionally configure transport parameters with
3208 // |SSL_set_quic_transport_params|. |SSL_get_peer_quic_transport_params| may be
3209 // used to query the value received from the peer. BoringSSL handles this
3210 // extension as an opaque byte string. The caller is responsible for serializing
3211 // and parsing them. See https://www.rfc-editor.org/rfc/rfc9000#section-7.4 for
3212 // details.
3213 //
3214 // QUIC additionally imposes restrictions on 0-RTT. In particular, the QUIC
3215 // transport layer requires that if a server accepts 0-RTT data, then the
3216 // transport parameters sent on the resumed connection must not lower any limits
3217 // compared to the transport parameters that the server sent on the connection
3218 // where the ticket for 0-RTT was issued. In effect, the server must remember
3219 // the transport parameters with the ticket. Application protocols running on
3220 // QUIC may impose similar restrictions, for example HTTP/3's restrictions on
3221 // SETTINGS frames.
3222 //
3223 // BoringSSL implements this check by doing a byte-for-byte comparison of an
3224 // opaque context passed in by the server. This context must be the same on the
3225 // connection where the ticket was issued and the connection where that ticket
3226 // is used for 0-RTT. If there is a mismatch, or the context was not set,
3227 // BoringSSL will reject early data (but not reject the resumption attempt).
3228 // This context is set via |SSL_set_quic_early_data_context| and should cover
3229 // both transport parameters and any application state.
3230 // |SSL_set_quic_early_data_context| must be called on the server with a
3231 // non-empty context if the server is to support 0-RTT in QUIC.
3232 //
3233 // BoringSSL does not perform any client-side checks on the transport
3234 // parameters received from a server that also accepted early data. It is up to
3235 // the caller to verify that the received transport parameters do not lower any
3236 // limits, and to close the QUIC connection if that is not the case. The same
3237 // holds for any application protocol state remembered for 0-RTT, e.g. HTTP/3
3238 // SETTINGS.
3239 
3240 // ssl_encryption_level_t represents a specific QUIC encryption level used to
3241 // transmit handshake messages.
3242 enum ssl_encryption_level_t BORINGSSL_ENUM_INT {
3243   ssl_encryption_initial = 0,
3244   ssl_encryption_early_data,
3245   ssl_encryption_handshake,
3246   ssl_encryption_application,
3247 };
3248 
3249 // ssl_quic_method_st (aka |SSL_QUIC_METHOD|) describes custom QUIC hooks.
3250 struct ssl_quic_method_st {
3251   // set_read_secret configures the read secret and cipher suite for the given
3252   // encryption level. It returns one on success and zero to terminate the
3253   // handshake with an error. It will be called at most once per encryption
3254   // level.
3255   //
3256   // BoringSSL will not release read keys before QUIC may use them. Once a level
3257   // has been initialized, QUIC may begin processing data from it. Handshake
3258   // data should be passed to |SSL_provide_quic_data| and application data (if
3259   // |level| is |ssl_encryption_early_data| or |ssl_encryption_application|) may
3260   // be processed according to the rules of the QUIC protocol.
3261   //
3262   // QUIC ACKs packets at the same encryption level they were received at,
3263   // except that client |ssl_encryption_early_data| (0-RTT) packets trigger
3264   // server |ssl_encryption_application| (1-RTT) ACKs. BoringSSL will always
3265   // install ACK-writing keys with |set_write_secret| before the packet-reading
3266   // keys with |set_read_secret|. This ensures the caller can always ACK any
3267   // packet it decrypts. Note this means the server installs 1-RTT write keys
3268   // before 0-RTT read keys.
3269   //
3270   // The converse is not true. An encryption level may be configured with write
3271   // secrets a roundtrip before the corresponding secrets for reading ACKs is
3272   // available.
3273   int (*set_read_secret)(SSL *ssl, enum ssl_encryption_level_t level,
3274                          const SSL_CIPHER *cipher, const uint8_t *secret,
3275                          size_t secret_len);
3276   // set_write_secret behaves like |set_read_secret| but configures the write
3277   // secret and cipher suite for the given encryption level. It will be called
3278   // at most once per encryption level.
3279   //
3280   // BoringSSL will not release write keys before QUIC may use them. If |level|
3281   // is |ssl_encryption_early_data| or |ssl_encryption_application|, QUIC may
3282   // begin sending application data at |level|. However, note that BoringSSL
3283   // configures server |ssl_encryption_application| write keys before the client
3284   // Finished. This allows QUIC to send half-RTT data, but the handshake is not
3285   // confirmed at this point and, if requesting client certificates, the client
3286   // is not yet authenticated.
3287   //
3288   // See |set_read_secret| for additional invariants between packets and their
3289   // ACKs.
3290   //
3291   // Note that, on 0-RTT reject, the |ssl_encryption_early_data| write secret
3292   // may use a different cipher suite from the other keys.
3293   int (*set_write_secret)(SSL *ssl, enum ssl_encryption_level_t level,
3294                           const SSL_CIPHER *cipher, const uint8_t *secret,
3295                           size_t secret_len);
3296   // add_handshake_data adds handshake data to the current flight at the given
3297   // encryption level. It returns one on success and zero on error.
3298   //
3299   // BoringSSL will pack data from a single encryption level together, but a
3300   // single handshake flight may include multiple encryption levels. Callers
3301   // should defer writing data to the network until |flush_flight| to better
3302   // pack QUIC packets into transport datagrams.
3303   //
3304   // If |level| is not |ssl_encryption_initial|, this function will not be
3305   // called before |level| is initialized with |set_write_secret|.
3306   int (*add_handshake_data)(SSL *ssl, enum ssl_encryption_level_t level,
3307                             const uint8_t *data, size_t len);
3308   // flush_flight is called when the current flight is complete and should be
3309   // written to the transport. Note a flight may contain data at several
3310   // encryption levels. It returns one on success and zero on error.
3311   int (*flush_flight)(SSL *ssl);
3312   // send_alert sends a fatal alert at the specified encryption level. It
3313   // returns one on success and zero on error.
3314   //
3315   // If |level| is not |ssl_encryption_initial|, this function will not be
3316   // called before |level| is initialized with |set_write_secret|.
3317   int (*send_alert)(SSL *ssl, enum ssl_encryption_level_t level, uint8_t alert);
3318 };
3319 
3320 // SSL_quic_max_handshake_flight_len returns returns the maximum number of bytes
3321 // that may be received at the given encryption level. This function should be
3322 // used to limit buffering in the QUIC implementation.
3323 //
3324 // See https://www.rfc-editor.org/rfc/rfc9000#section-7.5
3325 OPENSSL_EXPORT size_t SSL_quic_max_handshake_flight_len(
3326     const SSL *ssl, enum ssl_encryption_level_t level);
3327 
3328 // SSL_quic_read_level returns the current read encryption level.
3329 //
3330 // TODO(davidben): Is it still necessary to expose this function to callers?
3331 // QUICHE does not use it.
3332 OPENSSL_EXPORT enum ssl_encryption_level_t SSL_quic_read_level(const SSL *ssl);
3333 
3334 // SSL_quic_write_level returns the current write encryption level.
3335 //
3336 // TODO(davidben): Is it still necessary to expose this function to callers?
3337 // QUICHE does not use it.
3338 OPENSSL_EXPORT enum ssl_encryption_level_t SSL_quic_write_level(const SSL *ssl);
3339 
3340 // SSL_provide_quic_data provides data from QUIC at a particular encryption
3341 // level |level|. It returns one on success and zero on error. Note this
3342 // function will return zero if the handshake is not expecting data from |level|
3343 // at this time. The QUIC implementation should then close the connection with
3344 // an error.
3345 OPENSSL_EXPORT int SSL_provide_quic_data(SSL *ssl,
3346                                          enum ssl_encryption_level_t level,
3347                                          const uint8_t *data, size_t len);
3348 
3349 
3350 // SSL_process_quic_post_handshake processes any data that QUIC has provided
3351 // after the handshake has completed. This includes NewSessionTicket messages
3352 // sent by the server. It returns one on success and zero on error.
3353 OPENSSL_EXPORT int SSL_process_quic_post_handshake(SSL *ssl);
3354 
3355 // SSL_CTX_set_quic_method configures the QUIC hooks. This should only be
3356 // configured with a minimum version of TLS 1.3. |quic_method| must remain valid
3357 // for the lifetime of |ctx|. It returns one on success and zero on error.
3358 OPENSSL_EXPORT int SSL_CTX_set_quic_method(SSL_CTX *ctx,
3359                                            const SSL_QUIC_METHOD *quic_method);
3360 
3361 // SSL_set_quic_method configures the QUIC hooks. This should only be
3362 // configured with a minimum version of TLS 1.3. |quic_method| must remain valid
3363 // for the lifetime of |ssl|. It returns one on success and zero on error.
3364 OPENSSL_EXPORT int SSL_set_quic_method(SSL *ssl,
3365                                        const SSL_QUIC_METHOD *quic_method);
3366 
3367 // SSL_set_quic_transport_params configures |ssl| to send |params| (of length
3368 // |params_len|) in the quic_transport_parameters extension in either the
3369 // ClientHello or EncryptedExtensions handshake message. It is an error to set
3370 // transport parameters if |ssl| is not configured for QUIC. The buffer pointed
3371 // to by |params| only need be valid for the duration of the call to this
3372 // function. This function returns 1 on success and 0 on failure.
3373 OPENSSL_EXPORT int SSL_set_quic_transport_params(SSL *ssl,
3374                                                  const uint8_t *params,
3375                                                  size_t params_len);
3376 
3377 // SSL_get_peer_quic_transport_params provides the caller with the value of the
3378 // quic_transport_parameters extension sent by the peer. A pointer to the buffer
3379 // containing the TransportParameters will be put in |*out_params|, and its
3380 // length in |*params_len|. This buffer will be valid for the lifetime of the
3381 // |SSL|. If no params were received from the peer, |*out_params_len| will be 0.
3382 OPENSSL_EXPORT void SSL_get_peer_quic_transport_params(
3383     const SSL *ssl, const uint8_t **out_params, size_t *out_params_len);
3384 
3385 // SSL_set_quic_use_legacy_codepoint configures whether to use the legacy QUIC
3386 // extension codepoint 0xffa5 as opposed to the official value 57. Call with
3387 // |use_legacy| set to 1 to use 0xffa5 and call with 0 to use 57. By default,
3388 // the standard code point is used.
3389 OPENSSL_EXPORT void SSL_set_quic_use_legacy_codepoint(SSL *ssl, int use_legacy);
3390 
3391 // SSL_set_quic_early_data_context configures a context string in QUIC servers
3392 // for accepting early data. If a resumption connection offers early data, the
3393 // server will check if the value matches that of the connection which minted
3394 // the ticket. If not, resumption still succeeds but early data is rejected.
3395 // This should include all QUIC Transport Parameters except ones specified that
3396 // the client MUST NOT remember. This should also include any application
3397 // protocol-specific state. For HTTP/3, this should be the serialized server
3398 // SETTINGS frame and the QUIC Transport Parameters (except the stateless reset
3399 // token).
3400 //
3401 // This function may be called before |SSL_do_handshake| or during server
3402 // certificate selection. It returns 1 on success and 0 on failure.
3403 OPENSSL_EXPORT int SSL_set_quic_early_data_context(SSL *ssl,
3404                                                    const uint8_t *context,
3405                                                    size_t context_len);
3406 
3407 
3408 // Early data.
3409 //
3410 // WARNING: 0-RTT support in BoringSSL is currently experimental and not fully
3411 // implemented. It may cause interoperability or security failures when used.
3412 //
3413 // Early data, or 0-RTT, is a feature in TLS 1.3 which allows clients to send
3414 // data on the first flight during a resumption handshake. This can save a
3415 // round-trip in some application protocols.
3416 //
3417 // WARNING: A 0-RTT handshake has different security properties from normal
3418 // handshake, so it is off by default unless opted in. In particular, early data
3419 // is replayable by a network attacker. Callers must account for this when
3420 // sending or processing data before the handshake is confirmed. See RFC 8446
3421 // for more information.
3422 //
3423 // As a server, if early data is accepted, |SSL_do_handshake| will complete as
3424 // soon as the ClientHello is processed and server flight sent. |SSL_write| may
3425 // be used to send half-RTT data. |SSL_read| will consume early data and
3426 // transition to 1-RTT data as appropriate. Prior to the transition,
3427 // |SSL_in_init| will report the handshake is still in progress. Callers may use
3428 // it or |SSL_in_early_data| to defer or reject requests as needed.
3429 //
3430 // Early data as a client is more complex. If the offered session (see
3431 // |SSL_set_session|) is 0-RTT-capable, the handshake will return after sending
3432 // the ClientHello. The predicted peer certificates and ALPN protocol will be
3433 // available via the usual APIs. |SSL_write| will write early data, up to the
3434 // session's limit. Writes past this limit and |SSL_read| will complete the
3435 // handshake before continuing. Callers may also call |SSL_do_handshake| again
3436 // to complete the handshake sooner.
3437 //
3438 // If the server accepts early data, the handshake will succeed. |SSL_read| and
3439 // |SSL_write| will then act as in a 1-RTT handshake. The peer certificates and
3440 // ALPN protocol will be as predicted and need not be re-queried.
3441 //
3442 // If the server rejects early data, |SSL_do_handshake| (and thus |SSL_read| and
3443 // |SSL_write|) will then fail with |SSL_get_error| returning
3444 // |SSL_ERROR_EARLY_DATA_REJECTED|. The caller should treat this as a connection
3445 // error and most likely perform a high-level retry. Note the server may still
3446 // have processed the early data due to attacker replays.
3447 //
3448 // To then continue the handshake on the original connection, use
3449 // |SSL_reset_early_data_reject|. The connection will then behave as one which
3450 // had not yet completed the handshake. This allows a faster retry than making a
3451 // fresh connection. |SSL_do_handshake| will complete the full handshake,
3452 // possibly resulting in different peer certificates, ALPN protocol, and other
3453 // properties. The caller must disregard any values from before the reset and
3454 // query again.
3455 //
3456 // Finally, to implement the fallback described in RFC 8446 appendix D.3, retry
3457 // on a fresh connection without 0-RTT if the handshake fails with
3458 // |SSL_R_WRONG_VERSION_ON_EARLY_DATA|.
3459 
3460 // SSL_CTX_set_early_data_enabled sets whether early data is allowed to be used
3461 // with resumptions using |ctx|.
3462 OPENSSL_EXPORT void SSL_CTX_set_early_data_enabled(SSL_CTX *ctx, int enabled);
3463 
3464 // SSL_set_early_data_enabled sets whether early data is allowed to be used
3465 // with resumptions using |ssl|. See |SSL_CTX_set_early_data_enabled| for more
3466 // information.
3467 OPENSSL_EXPORT void SSL_set_early_data_enabled(SSL *ssl, int enabled);
3468 
3469 // SSL_in_early_data returns one if |ssl| has a pending handshake that has
3470 // progressed enough to send or receive early data. Clients may call |SSL_write|
3471 // to send early data, but |SSL_read| will complete the handshake before
3472 // accepting application data. Servers may call |SSL_read| to read early data
3473 // and |SSL_write| to send half-RTT data.
3474 OPENSSL_EXPORT int SSL_in_early_data(const SSL *ssl);
3475 
3476 // SSL_SESSION_early_data_capable returns whether early data would have been
3477 // attempted with |session| if enabled.
3478 OPENSSL_EXPORT int SSL_SESSION_early_data_capable(const SSL_SESSION *session);
3479 
3480 // SSL_SESSION_copy_without_early_data returns a copy of |session| with early
3481 // data disabled. If |session| already does not support early data, it returns
3482 // |session| with the reference count increased. The caller takes ownership of
3483 // the result and must release it with |SSL_SESSION_free|.
3484 //
3485 // This function may be used on the client to clear early data support from
3486 // existing sessions when the server rejects early data. In particular,
3487 // |SSL_R_WRONG_VERSION_ON_EARLY_DATA| requires a fresh connection to retry, and
3488 // the client would not want 0-RTT enabled for the next connection attempt.
3489 OPENSSL_EXPORT SSL_SESSION *SSL_SESSION_copy_without_early_data(
3490     SSL_SESSION *session);
3491 
3492 // SSL_early_data_accepted returns whether early data was accepted on the
3493 // handshake performed by |ssl|.
3494 OPENSSL_EXPORT int SSL_early_data_accepted(const SSL *ssl);
3495 
3496 // SSL_reset_early_data_reject resets |ssl| after an early data reject. All
3497 // 0-RTT state is discarded, including any pending |SSL_write| calls. The caller
3498 // should treat |ssl| as a logically fresh connection, usually by driving the
3499 // handshake to completion using |SSL_do_handshake|.
3500 //
3501 // It is an error to call this function on an |SSL| object that is not signaling
3502 // |SSL_ERROR_EARLY_DATA_REJECTED|.
3503 OPENSSL_EXPORT void SSL_reset_early_data_reject(SSL *ssl);
3504 
3505 // SSL_get_ticket_age_skew returns the difference, in seconds, between the
3506 // client-sent ticket age and the server-computed value in TLS 1.3 server
3507 // connections which resumed a session.
3508 OPENSSL_EXPORT int32_t SSL_get_ticket_age_skew(const SSL *ssl);
3509 
3510 // An ssl_early_data_reason_t describes why 0-RTT was accepted or rejected.
3511 // These values are persisted to logs. Entries should not be renumbered and
3512 // numeric values should never be reused.
3513 enum ssl_early_data_reason_t BORINGSSL_ENUM_INT {
3514   // The handshake has not progressed far enough for the 0-RTT status to be
3515   // known.
3516   ssl_early_data_unknown = 0,
3517   // 0-RTT is disabled for this connection.
3518   ssl_early_data_disabled = 1,
3519   // 0-RTT was accepted.
3520   ssl_early_data_accepted = 2,
3521   // The negotiated protocol version does not support 0-RTT.
3522   ssl_early_data_protocol_version = 3,
3523   // The peer declined to offer or accept 0-RTT for an unknown reason.
3524   ssl_early_data_peer_declined = 4,
3525   // The client did not offer a session.
3526   ssl_early_data_no_session_offered = 5,
3527   // The server declined to resume the session.
3528   ssl_early_data_session_not_resumed = 6,
3529   // The session does not support 0-RTT.
3530   ssl_early_data_unsupported_for_session = 7,
3531   // The server sent a HelloRetryRequest.
3532   ssl_early_data_hello_retry_request = 8,
3533   // The negotiated ALPN protocol did not match the session.
3534   ssl_early_data_alpn_mismatch = 9,
3535   // The connection negotiated Channel ID, which is incompatible with 0-RTT.
3536   ssl_early_data_channel_id = 10,
3537   // Value 11 is reserved. (It has historically |ssl_early_data_token_binding|.)
3538   // The client and server ticket age were too far apart.
3539   ssl_early_data_ticket_age_skew = 12,
3540   // QUIC parameters differ between this connection and the original.
3541   ssl_early_data_quic_parameter_mismatch = 13,
3542   // The application settings did not match the session.
3543   ssl_early_data_alps_mismatch = 14,
3544   // The value of the largest entry.
3545   ssl_early_data_reason_max_value = ssl_early_data_alps_mismatch,
3546 };
3547 
3548 // SSL_get_early_data_reason returns details why 0-RTT was accepted or rejected
3549 // on |ssl|. This is primarily useful on the server.
3550 OPENSSL_EXPORT enum ssl_early_data_reason_t SSL_get_early_data_reason(
3551     const SSL *ssl);
3552 
3553 // SSL_early_data_reason_string returns a string representation for |reason|, or
3554 // NULL if |reason| is unknown. This function may be used for logging.
3555 OPENSSL_EXPORT const char *SSL_early_data_reason_string(
3556     enum ssl_early_data_reason_t reason);
3557 
3558 
3559 // Encrypted ClientHello.
3560 //
3561 // ECH is a mechanism for encrypting the entire ClientHello message in TLS 1.3.
3562 // This can prevent observers from seeing cleartext information about the
3563 // connection, such as the server_name extension.
3564 //
3565 // By default, BoringSSL will treat the server name, session ticket, and client
3566 // certificate as secret, but most other parameters, such as the ALPN protocol
3567 // list will be treated as public and sent in the cleartext ClientHello. Other
3568 // APIs may be added for applications with different secrecy requirements.
3569 //
3570 // ECH support in BoringSSL is still experimental and under development.
3571 //
3572 // See https://tools.ietf.org/html/draft-ietf-tls-esni-13.
3573 
3574 // SSL_set_enable_ech_grease configures whether the client will send a GREASE
3575 // ECH extension when no supported ECHConfig is available.
3576 OPENSSL_EXPORT void SSL_set_enable_ech_grease(SSL *ssl, int enable);
3577 
3578 // SSL_set1_ech_config_list configures |ssl| to, as a client, offer ECH with the
3579 // specified configuration. |ech_config_list| should contain a serialized
3580 // ECHConfigList structure. It returns one on success and zero on error.
3581 //
3582 // This function returns an error if the input is malformed. If the input is
3583 // valid but none of the ECHConfigs implement supported parameters, it will
3584 // return success and proceed without ECH.
3585 //
3586 // If a supported ECHConfig is found, |ssl| will encrypt the true ClientHello
3587 // parameters. If the server cannot decrypt it, e.g. due to a key mismatch, ECH
3588 // has a recovery flow. |ssl| will handshake using the cleartext parameters,
3589 // including a public name in the ECHConfig. If using
3590 // |SSL_CTX_set_custom_verify|, callers should use |SSL_get0_ech_name_override|
3591 // to verify the certificate with the public name. If using the built-in
3592 // verifier, the |X509_STORE_CTX| will be configured automatically.
3593 //
3594 // If no other errors are found in this handshake, it will fail with
3595 // |SSL_R_ECH_REJECTED|. Since it didn't use the true parameters, the connection
3596 // cannot be used for application data. Instead, callers should handle this
3597 // error by calling |SSL_get0_ech_retry_configs| and retrying the connection
3598 // with updated ECH parameters. If the retry also fails with
3599 // |SSL_R_ECH_REJECTED|, the caller should report a connection failure.
3600 OPENSSL_EXPORT int SSL_set1_ech_config_list(SSL *ssl,
3601                                             const uint8_t *ech_config_list,
3602                                             size_t ech_config_list_len);
3603 
3604 // SSL_get0_ech_name_override, if |ssl| is a client and the server rejected ECH,
3605 // sets |*out_name| and |*out_name_len| to point to a buffer containing the ECH
3606 // public name. Otherwise, the buffer will be empty.
3607 //
3608 // When offering ECH as a client, this function should be called during the
3609 // certificate verification callback (see |SSL_CTX_set_custom_verify|). If
3610 // |*out_name_len| is non-zero, the caller should verify the certificate against
3611 // the result, interpreted as a DNS name, rather than the true server name. In
3612 // this case, the handshake will never succeed and is only used to authenticate
3613 // retry configs. See also |SSL_get0_ech_retry_configs|.
3614 OPENSSL_EXPORT void SSL_get0_ech_name_override(const SSL *ssl,
3615                                                const char **out_name,
3616                                                size_t *out_name_len);
3617 
3618 // SSL_get0_ech_retry_configs sets |*out_retry_configs| and
3619 // |*out_retry_configs_len| to a buffer containing a serialized ECHConfigList.
3620 // If the server did not provide an ECHConfigList, |*out_retry_configs_len| will
3621 // be zero.
3622 //
3623 // When handling an |SSL_R_ECH_REJECTED| error code as a client, callers should
3624 // use this function to recover from potential key mismatches. If the result is
3625 // non-empty, the caller should retry the connection, passing this buffer to
3626 // |SSL_set1_ech_config_list|. If the result is empty, the server has rolled
3627 // back ECH support, and the caller should retry without ECH.
3628 //
3629 // This function must only be called in response to an |SSL_R_ECH_REJECTED|
3630 // error code. Calling this function on |ssl|s that have not authenticated the
3631 // rejection handshake will assert in debug builds and otherwise return an
3632 // unparsable list.
3633 OPENSSL_EXPORT void SSL_get0_ech_retry_configs(
3634     const SSL *ssl, const uint8_t **out_retry_configs,
3635     size_t *out_retry_configs_len);
3636 
3637 // SSL_marshal_ech_config constructs a new serialized ECHConfig. On success, it
3638 // sets |*out| to a newly-allocated buffer containing the result and |*out_len|
3639 // to the size of the buffer. The caller must call |OPENSSL_free| on |*out| to
3640 // release the memory. On failure, it returns zero.
3641 //
3642 // The |config_id| field is a single byte identifer for the ECHConfig. Reusing
3643 // config IDs is allowed, but if multiple ECHConfigs with the same config ID are
3644 // active at a time, server load may increase. See
3645 // |SSL_ECH_KEYS_has_duplicate_config_id|.
3646 //
3647 // The public key and KEM algorithm are taken from |key|. |public_name| is the
3648 // DNS name used to authenticate the recovery flow. |max_name_len| should be the
3649 // length of the longest name in the ECHConfig's anonymity set and influences
3650 // client padding decisions.
3651 OPENSSL_EXPORT int SSL_marshal_ech_config(uint8_t **out, size_t *out_len,
3652                                           uint8_t config_id,
3653                                           const EVP_HPKE_KEY *key,
3654                                           const char *public_name,
3655                                           size_t max_name_len);
3656 
3657 // SSL_ECH_KEYS_new returns a newly-allocated |SSL_ECH_KEYS| or NULL on error.
3658 OPENSSL_EXPORT SSL_ECH_KEYS *SSL_ECH_KEYS_new(void);
3659 
3660 // SSL_ECH_KEYS_up_ref increments the reference count of |keys|.
3661 OPENSSL_EXPORT void SSL_ECH_KEYS_up_ref(SSL_ECH_KEYS *keys);
3662 
3663 // SSL_ECH_KEYS_free releases memory associated with |keys|.
3664 OPENSSL_EXPORT void SSL_ECH_KEYS_free(SSL_ECH_KEYS *keys);
3665 
3666 // SSL_ECH_KEYS_add decodes |ech_config| as an ECHConfig and appends it with
3667 // |key| to |keys|. If |is_retry_config| is non-zero, this config will be
3668 // returned to the client on configuration mismatch. It returns one on success
3669 // and zero on error.
3670 //
3671 // This function should be called successively to register each ECHConfig in
3672 // decreasing order of preference. This configuration must be completed before
3673 // setting |keys| on an |SSL_CTX| with |SSL_CTX_set1_ech_keys|. After that
3674 // point, |keys| is immutable; no more ECHConfig values may be added.
3675 //
3676 // See also |SSL_CTX_set1_ech_keys|.
3677 OPENSSL_EXPORT int SSL_ECH_KEYS_add(SSL_ECH_KEYS *keys, int is_retry_config,
3678                                     const uint8_t *ech_config,
3679                                     size_t ech_config_len,
3680                                     const EVP_HPKE_KEY *key);
3681 
3682 // SSL_ECH_KEYS_has_duplicate_config_id returns one if |keys| has duplicate
3683 // config IDs or zero otherwise. Duplicate config IDs still work, but may
3684 // increase server load due to trial decryption.
3685 OPENSSL_EXPORT int SSL_ECH_KEYS_has_duplicate_config_id(
3686     const SSL_ECH_KEYS *keys);
3687 
3688 // SSL_ECH_KEYS_marshal_retry_configs serializes the retry configs in |keys| as
3689 // an ECHConfigList. On success, it sets |*out| to a newly-allocated buffer
3690 // containing the result and |*out_len| to the size of the buffer. The caller
3691 // must call |OPENSSL_free| on |*out| to release the memory. On failure, it
3692 // returns zero.
3693 //
3694 // This output may be advertised to clients in DNS.
3695 OPENSSL_EXPORT int SSL_ECH_KEYS_marshal_retry_configs(const SSL_ECH_KEYS *keys,
3696                                                       uint8_t **out,
3697                                                       size_t *out_len);
3698 
3699 // SSL_CTX_set1_ech_keys configures |ctx| to use |keys| to decrypt encrypted
3700 // ClientHellos. It returns one on success, and zero on failure. If |keys| does
3701 // not contain any retry configs, this function will fail. Retry configs are
3702 // marked as such when they are added to |keys| with |SSL_ECH_KEYS_add|.
3703 //
3704 // Once |keys| has been passed to this function, it is immutable. Unlike most
3705 // |SSL_CTX| configuration functions, this function may be called even if |ctx|
3706 // already has associated connections on multiple threads. This may be used to
3707 // rotate keys in a long-lived server process.
3708 //
3709 // The configured ECHConfig values should also be advertised out-of-band via DNS
3710 // (see draft-ietf-dnsop-svcb-https). Before advertising an ECHConfig in DNS,
3711 // deployments should ensure all instances of the service are configured with
3712 // the ECHConfig and corresponding private key.
3713 //
3714 // Only the most recent fully-deployed ECHConfigs should be advertised in DNS.
3715 // |keys| may contain a newer set if those ECHConfigs are mid-deployment. It
3716 // should also contain older sets, until the DNS change has rolled out and the
3717 // old records have expired from caches.
3718 //
3719 // If there is a mismatch, |SSL| objects associated with |ctx| will complete the
3720 // handshake using the cleartext ClientHello and send updated ECHConfig values
3721 // to the client. The client will then retry to recover, but with a latency
3722 // penalty. This recovery flow depends on the public name in the ECHConfig.
3723 // Before advertising an ECHConfig in DNS, deployments must ensure all instances
3724 // of the service can present a valid certificate for the public name.
3725 //
3726 // BoringSSL negotiates ECH before certificate selection callbacks are called,
3727 // including |SSL_CTX_set_select_certificate_cb|. If ECH is negotiated, the
3728 // reported |SSL_CLIENT_HELLO| structure and |SSL_get_servername| function will
3729 // transparently reflect the inner ClientHello. Callers should select parameters
3730 // based on these values to correctly handle ECH as well as the recovery flow.
3731 OPENSSL_EXPORT int SSL_CTX_set1_ech_keys(SSL_CTX *ctx, SSL_ECH_KEYS *keys);
3732 
3733 // SSL_ech_accepted returns one if |ssl| negotiated ECH and zero otherwise.
3734 OPENSSL_EXPORT int SSL_ech_accepted(const SSL *ssl);
3735 
3736 
3737 // Alerts.
3738 //
3739 // TLS uses alerts to signal error conditions. Alerts have a type (warning or
3740 // fatal) and description. OpenSSL internally handles fatal alerts with
3741 // dedicated error codes (see |SSL_AD_REASON_OFFSET|). Except for close_notify,
3742 // warning alerts are silently ignored and may only be surfaced with
3743 // |SSL_CTX_set_info_callback|.
3744 
3745 // SSL_AD_REASON_OFFSET is the offset between error reasons and |SSL_AD_*|
3746 // values. Any error code under |ERR_LIB_SSL| with an error reason above this
3747 // value corresponds to an alert description. Consumers may add or subtract
3748 // |SSL_AD_REASON_OFFSET| to convert between them.
3749 //
3750 // make_errors.go reserves error codes above 1000 for manually-assigned errors.
3751 // This value must be kept in sync with reservedReasonCode in make_errors.h
3752 #define SSL_AD_REASON_OFFSET 1000
3753 
3754 // SSL_AD_* are alert descriptions.
3755 #define SSL_AD_CLOSE_NOTIFY SSL3_AD_CLOSE_NOTIFY
3756 #define SSL_AD_UNEXPECTED_MESSAGE SSL3_AD_UNEXPECTED_MESSAGE
3757 #define SSL_AD_BAD_RECORD_MAC SSL3_AD_BAD_RECORD_MAC
3758 #define SSL_AD_DECRYPTION_FAILED TLS1_AD_DECRYPTION_FAILED
3759 #define SSL_AD_RECORD_OVERFLOW TLS1_AD_RECORD_OVERFLOW
3760 #define SSL_AD_DECOMPRESSION_FAILURE SSL3_AD_DECOMPRESSION_FAILURE
3761 #define SSL_AD_HANDSHAKE_FAILURE SSL3_AD_HANDSHAKE_FAILURE
3762 #define SSL_AD_NO_CERTIFICATE SSL3_AD_NO_CERTIFICATE  // Legacy SSL 3.0 value
3763 #define SSL_AD_BAD_CERTIFICATE SSL3_AD_BAD_CERTIFICATE
3764 #define SSL_AD_UNSUPPORTED_CERTIFICATE SSL3_AD_UNSUPPORTED_CERTIFICATE
3765 #define SSL_AD_CERTIFICATE_REVOKED SSL3_AD_CERTIFICATE_REVOKED
3766 #define SSL_AD_CERTIFICATE_EXPIRED SSL3_AD_CERTIFICATE_EXPIRED
3767 #define SSL_AD_CERTIFICATE_UNKNOWN SSL3_AD_CERTIFICATE_UNKNOWN
3768 #define SSL_AD_ILLEGAL_PARAMETER SSL3_AD_ILLEGAL_PARAMETER
3769 #define SSL_AD_UNKNOWN_CA TLS1_AD_UNKNOWN_CA
3770 #define SSL_AD_ACCESS_DENIED TLS1_AD_ACCESS_DENIED
3771 #define SSL_AD_DECODE_ERROR TLS1_AD_DECODE_ERROR
3772 #define SSL_AD_DECRYPT_ERROR TLS1_AD_DECRYPT_ERROR
3773 #define SSL_AD_EXPORT_RESTRICTION TLS1_AD_EXPORT_RESTRICTION
3774 #define SSL_AD_PROTOCOL_VERSION TLS1_AD_PROTOCOL_VERSION
3775 #define SSL_AD_INSUFFICIENT_SECURITY TLS1_AD_INSUFFICIENT_SECURITY
3776 #define SSL_AD_INTERNAL_ERROR TLS1_AD_INTERNAL_ERROR
3777 #define SSL_AD_INAPPROPRIATE_FALLBACK SSL3_AD_INAPPROPRIATE_FALLBACK
3778 #define SSL_AD_USER_CANCELLED TLS1_AD_USER_CANCELLED
3779 #define SSL_AD_NO_RENEGOTIATION TLS1_AD_NO_RENEGOTIATION
3780 #define SSL_AD_MISSING_EXTENSION TLS1_AD_MISSING_EXTENSION
3781 #define SSL_AD_UNSUPPORTED_EXTENSION TLS1_AD_UNSUPPORTED_EXTENSION
3782 #define SSL_AD_CERTIFICATE_UNOBTAINABLE TLS1_AD_CERTIFICATE_UNOBTAINABLE
3783 #define SSL_AD_UNRECOGNIZED_NAME TLS1_AD_UNRECOGNIZED_NAME
3784 #define SSL_AD_BAD_CERTIFICATE_STATUS_RESPONSE \
3785   TLS1_AD_BAD_CERTIFICATE_STATUS_RESPONSE
3786 #define SSL_AD_BAD_CERTIFICATE_HASH_VALUE TLS1_AD_BAD_CERTIFICATE_HASH_VALUE
3787 #define SSL_AD_UNKNOWN_PSK_IDENTITY TLS1_AD_UNKNOWN_PSK_IDENTITY
3788 #define SSL_AD_CERTIFICATE_REQUIRED TLS1_AD_CERTIFICATE_REQUIRED
3789 #define SSL_AD_NO_APPLICATION_PROTOCOL TLS1_AD_NO_APPLICATION_PROTOCOL
3790 #define SSL_AD_ECH_REQUIRED TLS1_AD_ECH_REQUIRED
3791 
3792 // SSL_alert_type_string_long returns a string description of |value| as an
3793 // alert type (warning or fatal).
3794 OPENSSL_EXPORT const char *SSL_alert_type_string_long(int value);
3795 
3796 // SSL_alert_desc_string_long returns a string description of |value| as an
3797 // alert description or "unknown" if unknown.
3798 OPENSSL_EXPORT const char *SSL_alert_desc_string_long(int value);
3799 
3800 // SSL_send_fatal_alert sends a fatal alert over |ssl| of the specified type,
3801 // which should be one of the |SSL_AD_*| constants. It returns one on success
3802 // and <= 0 on error. The caller should pass the return value into
3803 // |SSL_get_error| to determine how to proceed. Once this function has been
3804 // called, future calls to |SSL_write| will fail.
3805 //
3806 // If retrying a failed operation due to |SSL_ERROR_WANT_WRITE|, subsequent
3807 // calls must use the same |alert| parameter.
3808 OPENSSL_EXPORT int SSL_send_fatal_alert(SSL *ssl, uint8_t alert);
3809 
3810 
3811 // ex_data functions.
3812 //
3813 // See |ex_data.h| for details.
3814 
3815 OPENSSL_EXPORT int SSL_set_ex_data(SSL *ssl, int idx, void *data);
3816 OPENSSL_EXPORT void *SSL_get_ex_data(const SSL *ssl, int idx);
3817 OPENSSL_EXPORT int SSL_get_ex_new_index(long argl, void *argp,
3818                                         CRYPTO_EX_unused *unused,
3819                                         CRYPTO_EX_dup *dup_unused,
3820                                         CRYPTO_EX_free *free_func);
3821 
3822 OPENSSL_EXPORT int SSL_SESSION_set_ex_data(SSL_SESSION *session, int idx,
3823                                            void *data);
3824 OPENSSL_EXPORT void *SSL_SESSION_get_ex_data(const SSL_SESSION *session,
3825                                              int idx);
3826 OPENSSL_EXPORT int SSL_SESSION_get_ex_new_index(long argl, void *argp,
3827                                                 CRYPTO_EX_unused *unused,
3828                                                 CRYPTO_EX_dup *dup_unused,
3829                                                 CRYPTO_EX_free *free_func);
3830 
3831 OPENSSL_EXPORT int SSL_CTX_set_ex_data(SSL_CTX *ctx, int idx, void *data);
3832 OPENSSL_EXPORT void *SSL_CTX_get_ex_data(const SSL_CTX *ctx, int idx);
3833 OPENSSL_EXPORT int SSL_CTX_get_ex_new_index(long argl, void *argp,
3834                                             CRYPTO_EX_unused *unused,
3835                                             CRYPTO_EX_dup *dup_unused,
3836                                             CRYPTO_EX_free *free_func);
3837 
3838 
3839 // Low-level record-layer state.
3840 
3841 // SSL_get_ivs sets |*out_iv_len| to the length of the IVs for the ciphers
3842 // underlying |ssl| and sets |*out_read_iv| and |*out_write_iv| to point to the
3843 // current IVs for the read and write directions. This is only meaningful for
3844 // connections with implicit IVs (i.e. CBC mode with TLS 1.0).
3845 //
3846 // It returns one on success or zero on error.
3847 OPENSSL_EXPORT int SSL_get_ivs(const SSL *ssl, const uint8_t **out_read_iv,
3848                                const uint8_t **out_write_iv,
3849                                size_t *out_iv_len);
3850 
3851 // SSL_get_key_block_len returns the length of |ssl|'s key block. It is an error
3852 // to call this function during a handshake.
3853 OPENSSL_EXPORT size_t SSL_get_key_block_len(const SSL *ssl);
3854 
3855 // SSL_generate_key_block generates |out_len| bytes of key material for |ssl|'s
3856 // current connection state. It is an error to call this function during a
3857 // handshake.
3858 OPENSSL_EXPORT int SSL_generate_key_block(const SSL *ssl, uint8_t *out,
3859                                           size_t out_len);
3860 
3861 // SSL_get_read_sequence returns, in TLS, the expected sequence number of the
3862 // next incoming record in the current epoch. In DTLS, it returns the maximum
3863 // sequence number received in the current epoch and includes the epoch number
3864 // in the two most significant bytes.
3865 OPENSSL_EXPORT uint64_t SSL_get_read_sequence(const SSL *ssl);
3866 
3867 // SSL_get_write_sequence returns the sequence number of the next outgoing
3868 // record in the current epoch. In DTLS, it includes the epoch number in the
3869 // two most significant bytes.
3870 OPENSSL_EXPORT uint64_t SSL_get_write_sequence(const SSL *ssl);
3871 
3872 
3873 // Handshake hints.
3874 //
3875 // *** EXPERIMENTAL — DO NOT USE WITHOUT CHECKING ***
3876 //
3877 // Some server deployments make asynchronous RPC calls in both ClientHello
3878 // dispatch and private key operations. In TLS handshakes where the private key
3879 // operation occurs in the first round-trip, this results in two consecutive RPC
3880 // round-trips. Handshake hints allow the RPC service to predicte a signature.
3881 // If correctly predicted, this can skip the second RPC call.
3882 //
3883 // First, the server installs a certificate selection callback (see
3884 // |SSL_CTX_set_select_certificate_cb|). When that is called, it performs the
3885 // RPC as before, but includes the ClientHello and a capabilities string from
3886 // |SSL_serialize_capabilities|.
3887 //
3888 // Next, the RPC service creates its own |SSL| object, applies the results of
3889 // certificate selection, calls |SSL_request_handshake_hints|, and runs the
3890 // handshake. If this successfully computes handshake hints (see
3891 // |SSL_serialize_handshake_hints|), the RPC server should send the hints
3892 // alongside any certificate selection results.
3893 //
3894 // Finally, the server calls |SSL_set_handshake_hints| and applies any
3895 // configuration from the RPC server. It then completes the handshake as before.
3896 // If the hints apply, BoringSSL will use the predicted signature and skip the
3897 // private key callbacks. Otherwise, BoringSSL will call private key callbacks
3898 // to generate a signature as before.
3899 //
3900 // Callers should synchronize configuration across the two services.
3901 // Configuration mismatches and some cases of version skew are not fatal, but
3902 // may result in the hints not applying. Additionally, some handshake flows use
3903 // the private key in later round-trips, such as TLS 1.3 HelloRetryRequest. In
3904 // those cases, BoringSSL will not predict a signature as there is no benefit.
3905 // Callers must allow for handshakes to complete without a predicted signature.
3906 //
3907 // For now, only TLS 1.3 is hinted. TLS 1.2 will work, but the hints will be
3908 // empty.
3909 
3910 // SSL_serialize_capabilities writes an opaque byte string to |out| describing
3911 // some of |ssl|'s capabilities. It returns one on success and zero on error.
3912 //
3913 // This string is used by BoringSSL internally to reduce the impact of version
3914 // skew.
3915 OPENSSL_EXPORT int SSL_serialize_capabilities(const SSL *ssl, CBB *out);
3916 
3917 // SSL_request_handshake_hints configures |ssl| to generate a handshake hint for
3918 // |client_hello|. It returns one on success and zero on error. |client_hello|
3919 // should contain a serialized ClientHello structure, from the |client_hello|
3920 // and |client_hello_len| fields of the |SSL_CLIENT_HELLO| structure.
3921 // |capabilities| should contain the output of |SSL_serialize_capabilities|.
3922 //
3923 // When configured, |ssl| will perform no I/O (so there is no need to configure
3924 // |BIO|s). For QUIC, the caller should still configure an |SSL_QUIC_METHOD|,
3925 // but the callbacks themselves will never be called and may be left NULL or
3926 // report failure. |SSL_provide_quic_data| also should not be called.
3927 //
3928 // If hint generation is successful, |SSL_do_handshake| will stop the handshake
3929 // early with |SSL_get_error| returning |SSL_ERROR_HANDSHAKE_HINTS_READY|. At
3930 // this point, the caller should run |SSL_serialize_handshake_hints| to extract
3931 // the resulting hints.
3932 //
3933 // Hint generation may fail if, e.g., |ssl| was unable to process the
3934 // ClientHello. Callers should then complete the certificate selection RPC and
3935 // continue the original handshake with no hint. It will likely fail, but this
3936 // reports the correct alert to the client and is more robust in case of
3937 // mismatch.
3938 OPENSSL_EXPORT int SSL_request_handshake_hints(SSL *ssl,
3939                                                const uint8_t *client_hello,
3940                                                size_t client_hello_len,
3941                                                const uint8_t *capabilities,
3942                                                size_t capabilities_len);
3943 
3944 // SSL_serialize_handshake_hints writes an opaque byte string to |out|
3945 // containing the handshake hints computed by |out|. It returns one on success
3946 // and zero on error. This function should only be called if
3947 // |SSL_request_handshake_hints| was configured and the handshake terminated
3948 // with |SSL_ERROR_HANDSHAKE_HINTS_READY|.
3949 //
3950 // This string may be passed to |SSL_set_handshake_hints| on another |SSL| to
3951 // avoid an extra signature call.
3952 OPENSSL_EXPORT int SSL_serialize_handshake_hints(const SSL *ssl, CBB *out);
3953 
3954 // SSL_set_handshake_hints configures |ssl| to use |hints| as handshake hints.
3955 // It returns one on success and zero on error. The handshake will then continue
3956 // as before, but apply predicted values from |hints| where applicable.
3957 //
3958 // Hints may contain connection and session secrets, so they must not leak and
3959 // must come from a source trusted to terminate the connection. However, they
3960 // will not change |ssl|'s configuration. The caller is responsible for
3961 // serializing and applying options from the RPC server as needed. This ensures
3962 // |ssl|'s behavior is self-consistent and consistent with the caller's local
3963 // decisions.
3964 OPENSSL_EXPORT int SSL_set_handshake_hints(SSL *ssl, const uint8_t *hints,
3965                                            size_t hints_len);
3966 
3967 
3968 // Obscure functions.
3969 
3970 // SSL_CTX_set_msg_callback installs |cb| as the message callback for |ctx|.
3971 // This callback will be called when sending or receiving low-level record
3972 // headers, complete handshake messages, ChangeCipherSpec, and alerts.
3973 // |write_p| is one for outgoing messages and zero for incoming messages.
3974 //
3975 // For each record header, |cb| is called with |version| = 0 and |content_type|
3976 // = |SSL3_RT_HEADER|. The |len| bytes from |buf| contain the header. Note that
3977 // this does not include the record body. If the record is sealed, the length
3978 // in the header is the length of the ciphertext.
3979 //
3980 // For each handshake message, ChangeCipherSpec, and alert, |version| is the
3981 // protocol version and |content_type| is the corresponding record type. The
3982 // |len| bytes from |buf| contain the handshake message, one-byte
3983 // ChangeCipherSpec body, and two-byte alert, respectively.
3984 //
3985 // For a V2ClientHello, |version| is |SSL2_VERSION|, |content_type| is zero, and
3986 // the |len| bytes from |buf| contain the V2ClientHello structure.
3987 OPENSSL_EXPORT void SSL_CTX_set_msg_callback(
3988     SSL_CTX *ctx, void (*cb)(int write_p, int version, int content_type,
3989                              const void *buf, size_t len, SSL *ssl, void *arg));
3990 
3991 // SSL_CTX_set_msg_callback_arg sets the |arg| parameter of the message
3992 // callback.
3993 OPENSSL_EXPORT void SSL_CTX_set_msg_callback_arg(SSL_CTX *ctx, void *arg);
3994 
3995 // SSL_set_msg_callback installs |cb| as the message callback of |ssl|. See
3996 // |SSL_CTX_set_msg_callback| for when this callback is called.
3997 OPENSSL_EXPORT void SSL_set_msg_callback(
3998     SSL *ssl, void (*cb)(int write_p, int version, int content_type,
3999                          const void *buf, size_t len, SSL *ssl, void *arg));
4000 
4001 // SSL_set_msg_callback_arg sets the |arg| parameter of the message callback.
4002 OPENSSL_EXPORT void SSL_set_msg_callback_arg(SSL *ssl, void *arg);
4003 
4004 // SSL_CTX_set_keylog_callback configures a callback to log key material. This
4005 // is intended for debugging use with tools like Wireshark. The |cb| function
4006 // should log |line| followed by a newline, synchronizing with any concurrent
4007 // access to the log.
4008 //
4009 // The format is described in
4010 // https://developer.mozilla.org/en-US/docs/Mozilla/Projects/NSS/Key_Log_Format.
4011 OPENSSL_EXPORT void SSL_CTX_set_keylog_callback(
4012     SSL_CTX *ctx, void (*cb)(const SSL *ssl, const char *line));
4013 
4014 // SSL_CTX_get_keylog_callback returns the callback configured by
4015 // |SSL_CTX_set_keylog_callback|.
4016 OPENSSL_EXPORT void (*SSL_CTX_get_keylog_callback(const SSL_CTX *ctx))(
4017     const SSL *ssl, const char *line);
4018 
4019 // SSL_CTX_set_current_time_cb configures a callback to retrieve the current
4020 // time, which should be set in |*out_clock|. This can be used for testing
4021 // purposes; for example, a callback can be configured that returns a time
4022 // set explicitly by the test. The |ssl| pointer passed to |cb| is always null.
4023 OPENSSL_EXPORT void SSL_CTX_set_current_time_cb(
4024     SSL_CTX *ctx, void (*cb)(const SSL *ssl, struct timeval *out_clock));
4025 
4026 // SSL_set_shed_handshake_config allows some of the configuration of |ssl| to be
4027 // freed after its handshake completes.  Once configuration has been shed, APIs
4028 // that query it may fail.  "Configuration" in this context means anything that
4029 // was set by the caller, as distinct from information derived from the
4030 // handshake.  For example, |SSL_get_ciphers| queries how the |SSL| was
4031 // configured by the caller, and fails after configuration has been shed,
4032 // whereas |SSL_get_cipher| queries the result of the handshake, and is
4033 // unaffected by configuration shedding.
4034 //
4035 // If configuration shedding is enabled, it is an error to call |SSL_clear|.
4036 //
4037 // Note that configuration shedding as a client additionally depends on
4038 // renegotiation being disabled (see |SSL_set_renegotiate_mode|). If
4039 // renegotiation is possible, the configuration will be retained. If
4040 // configuration shedding is enabled and renegotiation later disabled after the
4041 // handshake, |SSL_set_renegotiate_mode| will shed configuration then. This may
4042 // be useful for clients which support renegotiation with some ALPN protocols,
4043 // such as HTTP/1.1, and not others, such as HTTP/2.
4044 OPENSSL_EXPORT void SSL_set_shed_handshake_config(SSL *ssl, int enable);
4045 
4046 enum ssl_renegotiate_mode_t BORINGSSL_ENUM_INT {
4047   ssl_renegotiate_never = 0,
4048   ssl_renegotiate_once,
4049   ssl_renegotiate_freely,
4050   ssl_renegotiate_ignore,
4051   ssl_renegotiate_explicit,
4052 };
4053 
4054 // SSL_set_renegotiate_mode configures how |ssl|, a client, reacts to
4055 // renegotiation attempts by a server. If |ssl| is a server, peer-initiated
4056 // renegotiations are *always* rejected and this function does nothing.
4057 //
4058 // The renegotiation mode defaults to |ssl_renegotiate_never|, but may be set
4059 // at any point in a connection's lifetime. Set it to |ssl_renegotiate_once| to
4060 // allow one renegotiation, |ssl_renegotiate_freely| to allow all
4061 // renegotiations or |ssl_renegotiate_ignore| to ignore HelloRequest messages.
4062 // Note that ignoring HelloRequest messages may cause the connection to stall
4063 // if the server waits for the renegotiation to complete.
4064 //
4065 // If set to |ssl_renegotiate_explicit|, |SSL_read| and |SSL_peek| calls which
4066 // encounter a HelloRequest will pause with |SSL_ERROR_WANT_RENEGOTIATE|.
4067 // |SSL_write| will continue to work while paused. The caller may call
4068 // |SSL_renegotiate| to begin the renegotiation at a later point. This mode may
4069 // be used if callers wish to eagerly call |SSL_peek| without triggering a
4070 // renegotiation.
4071 //
4072 // If configuration shedding is enabled (see |SSL_set_shed_handshake_config|),
4073 // configuration is released if, at any point after the handshake, renegotiation
4074 // is disabled. It is not possible to switch from disabling renegotiation to
4075 // enabling it on a given connection. Callers that condition renegotiation on,
4076 // e.g., ALPN must enable renegotiation before the handshake and conditionally
4077 // disable it afterwards.
4078 //
4079 // There is no support in BoringSSL for initiating renegotiations as a client
4080 // or server.
4081 OPENSSL_EXPORT void SSL_set_renegotiate_mode(SSL *ssl,
4082                                              enum ssl_renegotiate_mode_t mode);
4083 
4084 // SSL_renegotiate starts a deferred renegotiation on |ssl| if it was configured
4085 // with |ssl_renegotiate_explicit| and has a pending HelloRequest. It returns
4086 // one on success and zero on error.
4087 //
4088 // This function does not do perform any I/O. On success, a subsequent
4089 // |SSL_do_handshake| call will run the handshake. |SSL_write| and
4090 // |SSL_read| will also complete the handshake before sending or receiving
4091 // application data.
4092 OPENSSL_EXPORT int SSL_renegotiate(SSL *ssl);
4093 
4094 // SSL_renegotiate_pending returns one if |ssl| is in the middle of a
4095 // renegotiation.
4096 OPENSSL_EXPORT int SSL_renegotiate_pending(SSL *ssl);
4097 
4098 // SSL_total_renegotiations returns the total number of renegotiation handshakes
4099 // performed by |ssl|. This includes the pending renegotiation, if any.
4100 OPENSSL_EXPORT int SSL_total_renegotiations(const SSL *ssl);
4101 
4102 // SSL_MAX_CERT_LIST_DEFAULT is the default maximum length, in bytes, of a peer
4103 // certificate chain.
4104 #define SSL_MAX_CERT_LIST_DEFAULT (1024 * 100)
4105 
4106 // SSL_CTX_get_max_cert_list returns the maximum length, in bytes, of a peer
4107 // certificate chain accepted by |ctx|.
4108 OPENSSL_EXPORT size_t SSL_CTX_get_max_cert_list(const SSL_CTX *ctx);
4109 
4110 // SSL_CTX_set_max_cert_list sets the maximum length, in bytes, of a peer
4111 // certificate chain to |max_cert_list|. This affects how much memory may be
4112 // consumed during the handshake.
4113 OPENSSL_EXPORT void SSL_CTX_set_max_cert_list(SSL_CTX *ctx,
4114                                               size_t max_cert_list);
4115 
4116 // SSL_get_max_cert_list returns the maximum length, in bytes, of a peer
4117 // certificate chain accepted by |ssl|.
4118 OPENSSL_EXPORT size_t SSL_get_max_cert_list(const SSL *ssl);
4119 
4120 // SSL_set_max_cert_list sets the maximum length, in bytes, of a peer
4121 // certificate chain to |max_cert_list|. This affects how much memory may be
4122 // consumed during the handshake.
4123 OPENSSL_EXPORT void SSL_set_max_cert_list(SSL *ssl, size_t max_cert_list);
4124 
4125 // SSL_CTX_set_max_send_fragment sets the maximum length, in bytes, of records
4126 // sent by |ctx|. Beyond this length, handshake messages and application data
4127 // will be split into multiple records. It returns one on success or zero on
4128 // error.
4129 OPENSSL_EXPORT int SSL_CTX_set_max_send_fragment(SSL_CTX *ctx,
4130                                                  size_t max_send_fragment);
4131 
4132 // SSL_set_max_send_fragment sets the maximum length, in bytes, of records sent
4133 // by |ssl|. Beyond this length, handshake messages and application data will
4134 // be split into multiple records. It returns one on success or zero on
4135 // error.
4136 OPENSSL_EXPORT int SSL_set_max_send_fragment(SSL *ssl,
4137                                              size_t max_send_fragment);
4138 
4139 // ssl_early_callback_ctx (aka |SSL_CLIENT_HELLO|) is passed to certain
4140 // callbacks that are called very early on during the server handshake. At this
4141 // point, much of the SSL* hasn't been filled out and only the ClientHello can
4142 // be depended on.
4143 typedef struct ssl_early_callback_ctx {
4144   SSL *ssl;
4145   const uint8_t *client_hello;
4146   size_t client_hello_len;
4147   uint16_t version;
4148   const uint8_t *random;
4149   size_t random_len;
4150   const uint8_t *session_id;
4151   size_t session_id_len;
4152   const uint8_t *cipher_suites;
4153   size_t cipher_suites_len;
4154   const uint8_t *compression_methods;
4155   size_t compression_methods_len;
4156   const uint8_t *extensions;
4157   size_t extensions_len;
4158 } SSL_CLIENT_HELLO;
4159 
4160 // ssl_select_cert_result_t enumerates the possible results from selecting a
4161 // certificate with |select_certificate_cb|.
4162 enum ssl_select_cert_result_t BORINGSSL_ENUM_INT {
4163   // ssl_select_cert_success indicates that the certificate selection was
4164   // successful.
4165   ssl_select_cert_success = 1,
4166   // ssl_select_cert_retry indicates that the operation could not be
4167   // immediately completed and must be reattempted at a later point.
4168   ssl_select_cert_retry = 0,
4169   // ssl_select_cert_error indicates that a fatal error occured and the
4170   // handshake should be terminated.
4171   ssl_select_cert_error = -1,
4172 };
4173 
4174 // SSL_early_callback_ctx_extension_get searches the extensions in
4175 // |client_hello| for an extension of the given type. If not found, it returns
4176 // zero. Otherwise it sets |out_data| to point to the extension contents (not
4177 // including the type and length bytes), sets |out_len| to the length of the
4178 // extension contents and returns one.
4179 OPENSSL_EXPORT int SSL_early_callback_ctx_extension_get(
4180     const SSL_CLIENT_HELLO *client_hello, uint16_t extension_type,
4181     const uint8_t **out_data, size_t *out_len);
4182 
4183 // SSL_CTX_set_select_certificate_cb sets a callback that is called before most
4184 // ClientHello processing and before the decision whether to resume a session
4185 // is made. The callback may inspect the ClientHello and configure the
4186 // connection. See |ssl_select_cert_result_t| for details of the return values.
4187 //
4188 // In the case that a retry is indicated, |SSL_get_error| will return
4189 // |SSL_ERROR_PENDING_CERTIFICATE| and the caller should arrange for the
4190 // high-level operation on |ssl| to be retried at a later time, which will
4191 // result in another call to |cb|.
4192 //
4193 // |SSL_get_servername| may be used during this callback.
4194 //
4195 // Note: The |SSL_CLIENT_HELLO| is only valid for the duration of the callback
4196 // and is not valid while the handshake is paused.
4197 OPENSSL_EXPORT void SSL_CTX_set_select_certificate_cb(
4198     SSL_CTX *ctx,
4199     enum ssl_select_cert_result_t (*cb)(const SSL_CLIENT_HELLO *));
4200 
4201 // SSL_CTX_set_dos_protection_cb sets a callback that is called once the
4202 // resumption decision for a ClientHello has been made. It can return one to
4203 // allow the handshake to continue or zero to cause the handshake to abort.
4204 OPENSSL_EXPORT void SSL_CTX_set_dos_protection_cb(
4205     SSL_CTX *ctx, int (*cb)(const SSL_CLIENT_HELLO *));
4206 
4207 // SSL_CTX_set_reverify_on_resume configures whether the certificate
4208 // verification callback will be used to reverify stored certificates
4209 // when resuming a session. This only works with |SSL_CTX_set_custom_verify|.
4210 // For now, this is incompatible with |SSL_VERIFY_NONE| mode, and is only
4211 // respected on clients.
4212 OPENSSL_EXPORT void SSL_CTX_set_reverify_on_resume(SSL_CTX *ctx, int enabled);
4213 
4214 // SSL_set_enforce_rsa_key_usage configures whether the keyUsage extension of
4215 // RSA leaf certificates will be checked for consistency with the TLS
4216 // usage. This parameter may be set late; it will not be read until after the
4217 // certificate verification callback.
4218 OPENSSL_EXPORT void SSL_set_enforce_rsa_key_usage(SSL *ssl, int enabled);
4219 
4220 // SSL_ST_* are possible values for |SSL_state|, the bitmasks that make them up,
4221 // and some historical values for compatibility. Only |SSL_ST_INIT| and
4222 // |SSL_ST_OK| are ever returned.
4223 #define SSL_ST_CONNECT 0x1000
4224 #define SSL_ST_ACCEPT 0x2000
4225 #define SSL_ST_MASK 0x0FFF
4226 #define SSL_ST_INIT (SSL_ST_CONNECT | SSL_ST_ACCEPT)
4227 #define SSL_ST_OK 0x03
4228 #define SSL_ST_RENEGOTIATE (0x04 | SSL_ST_INIT)
4229 #define SSL_ST_BEFORE (0x05 | SSL_ST_INIT)
4230 
4231 // TLS_ST_* are aliases for |SSL_ST_*| for OpenSSL 1.1.0 compatibility.
4232 #define TLS_ST_OK SSL_ST_OK
4233 #define TLS_ST_BEFORE SSL_ST_BEFORE
4234 
4235 // SSL_CB_* are possible values for the |type| parameter in the info
4236 // callback and the bitmasks that make them up.
4237 #define SSL_CB_LOOP 0x01
4238 #define SSL_CB_EXIT 0x02
4239 #define SSL_CB_READ 0x04
4240 #define SSL_CB_WRITE 0x08
4241 #define SSL_CB_ALERT 0x4000
4242 #define SSL_CB_READ_ALERT (SSL_CB_ALERT | SSL_CB_READ)
4243 #define SSL_CB_WRITE_ALERT (SSL_CB_ALERT | SSL_CB_WRITE)
4244 #define SSL_CB_ACCEPT_LOOP (SSL_ST_ACCEPT | SSL_CB_LOOP)
4245 #define SSL_CB_ACCEPT_EXIT (SSL_ST_ACCEPT | SSL_CB_EXIT)
4246 #define SSL_CB_CONNECT_LOOP (SSL_ST_CONNECT | SSL_CB_LOOP)
4247 #define SSL_CB_CONNECT_EXIT (SSL_ST_CONNECT | SSL_CB_EXIT)
4248 #define SSL_CB_HANDSHAKE_START 0x10
4249 #define SSL_CB_HANDSHAKE_DONE 0x20
4250 
4251 // SSL_CTX_set_info_callback configures a callback to be run when various
4252 // events occur during a connection's lifetime. The |type| argument determines
4253 // the type of event and the meaning of the |value| argument. Callbacks must
4254 // ignore unexpected |type| values.
4255 //
4256 // |SSL_CB_READ_ALERT| is signaled for each alert received, warning or fatal.
4257 // The |value| argument is a 16-bit value where the alert level (either
4258 // |SSL3_AL_WARNING| or |SSL3_AL_FATAL|) is in the most-significant eight bits
4259 // and the alert type (one of |SSL_AD_*|) is in the least-significant eight.
4260 //
4261 // |SSL_CB_WRITE_ALERT| is signaled for each alert sent. The |value| argument
4262 // is constructed as with |SSL_CB_READ_ALERT|.
4263 //
4264 // |SSL_CB_HANDSHAKE_START| is signaled when a handshake begins. The |value|
4265 // argument is always one.
4266 //
4267 // |SSL_CB_HANDSHAKE_DONE| is signaled when a handshake completes successfully.
4268 // The |value| argument is always one. If a handshake False Starts, this event
4269 // may be used to determine when the Finished message is received.
4270 //
4271 // The following event types expose implementation details of the handshake
4272 // state machine. Consuming them is deprecated.
4273 //
4274 // |SSL_CB_ACCEPT_LOOP| (respectively, |SSL_CB_CONNECT_LOOP|) is signaled when
4275 // a server (respectively, client) handshake progresses. The |value| argument
4276 // is always one.
4277 //
4278 // |SSL_CB_ACCEPT_EXIT| (respectively, |SSL_CB_CONNECT_EXIT|) is signaled when
4279 // a server (respectively, client) handshake completes, fails, or is paused.
4280 // The |value| argument is one if the handshake succeeded and <= 0
4281 // otherwise.
4282 OPENSSL_EXPORT void SSL_CTX_set_info_callback(
4283     SSL_CTX *ctx, void (*cb)(const SSL *ssl, int type, int value));
4284 
4285 // SSL_CTX_get_info_callback returns the callback set by
4286 // |SSL_CTX_set_info_callback|.
4287 OPENSSL_EXPORT void (*SSL_CTX_get_info_callback(SSL_CTX *ctx))(const SSL *ssl,
4288                                                                int type,
4289                                                                int value);
4290 
4291 // SSL_set_info_callback configures a callback to be run at various events
4292 // during a connection's lifetime. See |SSL_CTX_set_info_callback|.
4293 OPENSSL_EXPORT void SSL_set_info_callback(
4294     SSL *ssl, void (*cb)(const SSL *ssl, int type, int value));
4295 
4296 // SSL_get_info_callback returns the callback set by |SSL_set_info_callback|.
4297 OPENSSL_EXPORT void (*SSL_get_info_callback(const SSL *ssl))(const SSL *ssl,
4298                                                              int type,
4299                                                              int value);
4300 
4301 // SSL_state_string_long returns the current state of the handshake state
4302 // machine as a string. This may be useful for debugging and logging.
4303 OPENSSL_EXPORT const char *SSL_state_string_long(const SSL *ssl);
4304 
4305 #define SSL_SENT_SHUTDOWN 1
4306 #define SSL_RECEIVED_SHUTDOWN 2
4307 
4308 // SSL_get_shutdown returns a bitmask with a subset of |SSL_SENT_SHUTDOWN| and
4309 // |SSL_RECEIVED_SHUTDOWN| to query whether close_notify was sent or received,
4310 // respectively.
4311 OPENSSL_EXPORT int SSL_get_shutdown(const SSL *ssl);
4312 
4313 // SSL_get_peer_signature_algorithm returns the signature algorithm used by the
4314 // peer. If not applicable, it returns zero.
4315 OPENSSL_EXPORT uint16_t SSL_get_peer_signature_algorithm(const SSL *ssl);
4316 
4317 // SSL_get_client_random writes up to |max_out| bytes of the most recent
4318 // handshake's client_random to |out| and returns the number of bytes written.
4319 // If |max_out| is zero, it returns the size of the client_random.
4320 OPENSSL_EXPORT size_t SSL_get_client_random(const SSL *ssl, uint8_t *out,
4321                                             size_t max_out);
4322 
4323 // SSL_get_server_random writes up to |max_out| bytes of the most recent
4324 // handshake's server_random to |out| and returns the number of bytes written.
4325 // If |max_out| is zero, it returns the size of the server_random.
4326 OPENSSL_EXPORT size_t SSL_get_server_random(const SSL *ssl, uint8_t *out,
4327                                             size_t max_out);
4328 
4329 // SSL_get_pending_cipher returns the cipher suite for the current handshake or
4330 // NULL if one has not been negotiated yet or there is no pending handshake.
4331 OPENSSL_EXPORT const SSL_CIPHER *SSL_get_pending_cipher(const SSL *ssl);
4332 
4333 // SSL_set_retain_only_sha256_of_client_certs, on a server, sets whether only
4334 // the SHA-256 hash of peer's certificate should be saved in memory and in the
4335 // session. This can save memory, ticket size and session cache space. If
4336 // enabled, |SSL_get_peer_certificate| will return NULL after the handshake
4337 // completes. See |SSL_SESSION_has_peer_sha256| and
4338 // |SSL_SESSION_get0_peer_sha256| to query the hash.
4339 OPENSSL_EXPORT void SSL_set_retain_only_sha256_of_client_certs(SSL *ssl,
4340                                                                int enable);
4341 
4342 // SSL_CTX_set_retain_only_sha256_of_client_certs, on a server, sets whether
4343 // only the SHA-256 hash of peer's certificate should be saved in memory and in
4344 // the session. This can save memory, ticket size and session cache space. If
4345 // enabled, |SSL_get_peer_certificate| will return NULL after the handshake
4346 // completes. See |SSL_SESSION_has_peer_sha256| and
4347 // |SSL_SESSION_get0_peer_sha256| to query the hash.
4348 OPENSSL_EXPORT void SSL_CTX_set_retain_only_sha256_of_client_certs(SSL_CTX *ctx,
4349                                                                    int enable);
4350 
4351 // SSL_CTX_set_grease_enabled configures whether sockets on |ctx| should enable
4352 // GREASE. See RFC 8701.
4353 OPENSSL_EXPORT void SSL_CTX_set_grease_enabled(SSL_CTX *ctx, int enabled);
4354 
4355 // SSL_CTX_set_permute_extensions configures whether sockets on |ctx| should
4356 // permute extensions. For now, this is only implemented for the ClientHello.
4357 OPENSSL_EXPORT void SSL_CTX_set_permute_extensions(SSL_CTX *ctx, int enabled);
4358 
4359 // SSL_set_permute_extensions configures whether sockets on |ssl| should
4360 // permute extensions. For now, this is only implemented for the ClientHello.
4361 OPENSSL_EXPORT void SSL_set_permute_extensions(SSL *ssl, int enabled);
4362 
4363 // SSL_max_seal_overhead returns the maximum overhead, in bytes, of sealing a
4364 // record with |ssl|.
4365 OPENSSL_EXPORT size_t SSL_max_seal_overhead(const SSL *ssl);
4366 
4367 // SSL_CTX_set_false_start_allowed_without_alpn configures whether connections
4368 // on |ctx| may use False Start (if |SSL_MODE_ENABLE_FALSE_START| is enabled)
4369 // without negotiating ALPN.
4370 OPENSSL_EXPORT void SSL_CTX_set_false_start_allowed_without_alpn(SSL_CTX *ctx,
4371                                                                  int allowed);
4372 
4373 // SSL_used_hello_retry_request returns one if the TLS 1.3 HelloRetryRequest
4374 // message has been either sent by the server or received by the client. It
4375 // returns zero otherwise.
4376 OPENSSL_EXPORT int SSL_used_hello_retry_request(const SSL *ssl);
4377 
4378 // SSL_set_jdk11_workaround configures whether to workaround various bugs in
4379 // JDK 11's TLS 1.3 implementation by disabling TLS 1.3 for such clients.
4380 //
4381 // https://bugs.openjdk.java.net/browse/JDK-8211806
4382 // https://bugs.openjdk.java.net/browse/JDK-8212885
4383 // https://bugs.openjdk.java.net/browse/JDK-8213202
4384 OPENSSL_EXPORT void SSL_set_jdk11_workaround(SSL *ssl, int enable);
4385 
4386 
4387 // Deprecated functions.
4388 
4389 // SSL_library_init calls |CRYPTO_library_init| and returns one.
4390 OPENSSL_EXPORT int SSL_library_init(void);
4391 
4392 // SSL_CIPHER_description writes a description of |cipher| into |buf| and
4393 // returns |buf|. If |buf| is NULL, it returns a newly allocated string, to be
4394 // freed with |OPENSSL_free|, or NULL on error.
4395 //
4396 // The description includes a trailing newline and has the form:
4397 // AES128-SHA              Kx=RSA      Au=RSA  Enc=AES(128)  Mac=SHA1
4398 //
4399 // Consider |SSL_CIPHER_standard_name| or |SSL_CIPHER_get_name| instead.
4400 OPENSSL_EXPORT const char *SSL_CIPHER_description(const SSL_CIPHER *cipher,
4401                                                   char *buf, int len);
4402 
4403 // SSL_CIPHER_get_version returns the string "TLSv1/SSLv3".
4404 OPENSSL_EXPORT const char *SSL_CIPHER_get_version(const SSL_CIPHER *cipher);
4405 
4406 // SSL_CIPHER_get_rfc_name returns a newly-allocated string containing the
4407 // result of |SSL_CIPHER_standard_name| or NULL on error. The caller is
4408 // responsible for calling |OPENSSL_free| on the result.
4409 //
4410 // Use |SSL_CIPHER_standard_name| instead.
4411 OPENSSL_EXPORT char *SSL_CIPHER_get_rfc_name(const SSL_CIPHER *cipher);
4412 
4413 typedef void COMP_METHOD;
4414 typedef struct ssl_comp_st SSL_COMP;
4415 
4416 // SSL_COMP_get_compression_methods returns NULL.
4417 OPENSSL_EXPORT STACK_OF(SSL_COMP) *SSL_COMP_get_compression_methods(void);
4418 
4419 // SSL_COMP_add_compression_method returns one.
4420 OPENSSL_EXPORT int SSL_COMP_add_compression_method(int id, COMP_METHOD *cm);
4421 
4422 // SSL_COMP_get_name returns NULL.
4423 OPENSSL_EXPORT const char *SSL_COMP_get_name(const COMP_METHOD *comp);
4424 
4425 // SSL_COMP_get0_name returns the |name| member of |comp|.
4426 OPENSSL_EXPORT const char *SSL_COMP_get0_name(const SSL_COMP *comp);
4427 
4428 // SSL_COMP_get_id returns the |id| member of |comp|.
4429 OPENSSL_EXPORT int SSL_COMP_get_id(const SSL_COMP *comp);
4430 
4431 // SSL_COMP_free_compression_methods does nothing.
4432 OPENSSL_EXPORT void SSL_COMP_free_compression_methods(void);
4433 
4434 // SSLv23_method calls |TLS_method|.
4435 OPENSSL_EXPORT const SSL_METHOD *SSLv23_method(void);
4436 
4437 // These version-specific methods behave exactly like |TLS_method| and
4438 // |DTLS_method| except they also call |SSL_CTX_set_min_proto_version| and
4439 // |SSL_CTX_set_max_proto_version| to lock connections to that protocol
4440 // version.
4441 OPENSSL_EXPORT const SSL_METHOD *TLSv1_method(void);
4442 OPENSSL_EXPORT const SSL_METHOD *TLSv1_1_method(void);
4443 OPENSSL_EXPORT const SSL_METHOD *TLSv1_2_method(void);
4444 OPENSSL_EXPORT const SSL_METHOD *DTLSv1_method(void);
4445 OPENSSL_EXPORT const SSL_METHOD *DTLSv1_2_method(void);
4446 
4447 // These client- and server-specific methods call their corresponding generic
4448 // methods.
4449 OPENSSL_EXPORT const SSL_METHOD *TLS_server_method(void);
4450 OPENSSL_EXPORT const SSL_METHOD *TLS_client_method(void);
4451 OPENSSL_EXPORT const SSL_METHOD *SSLv23_server_method(void);
4452 OPENSSL_EXPORT const SSL_METHOD *SSLv23_client_method(void);
4453 OPENSSL_EXPORT const SSL_METHOD *TLSv1_server_method(void);
4454 OPENSSL_EXPORT const SSL_METHOD *TLSv1_client_method(void);
4455 OPENSSL_EXPORT const SSL_METHOD *TLSv1_1_server_method(void);
4456 OPENSSL_EXPORT const SSL_METHOD *TLSv1_1_client_method(void);
4457 OPENSSL_EXPORT const SSL_METHOD *TLSv1_2_server_method(void);
4458 OPENSSL_EXPORT const SSL_METHOD *TLSv1_2_client_method(void);
4459 OPENSSL_EXPORT const SSL_METHOD *DTLS_server_method(void);
4460 OPENSSL_EXPORT const SSL_METHOD *DTLS_client_method(void);
4461 OPENSSL_EXPORT const SSL_METHOD *DTLSv1_server_method(void);
4462 OPENSSL_EXPORT const SSL_METHOD *DTLSv1_client_method(void);
4463 OPENSSL_EXPORT const SSL_METHOD *DTLSv1_2_server_method(void);
4464 OPENSSL_EXPORT const SSL_METHOD *DTLSv1_2_client_method(void);
4465 
4466 // SSL_clear resets |ssl| to allow another connection and returns one on success
4467 // or zero on failure. It returns most configuration state but releases memory
4468 // associated with the current connection.
4469 //
4470 // Free |ssl| and create a new one instead.
4471 OPENSSL_EXPORT int SSL_clear(SSL *ssl);
4472 
4473 // SSL_CTX_set_tmp_rsa_callback does nothing.
4474 OPENSSL_EXPORT void SSL_CTX_set_tmp_rsa_callback(
4475     SSL_CTX *ctx, RSA *(*cb)(SSL *ssl, int is_export, int keylength));
4476 
4477 // SSL_set_tmp_rsa_callback does nothing.
4478 OPENSSL_EXPORT void SSL_set_tmp_rsa_callback(SSL *ssl,
4479                                              RSA *(*cb)(SSL *ssl, int is_export,
4480                                                         int keylength));
4481 
4482 // SSL_CTX_sess_connect returns zero.
4483 OPENSSL_EXPORT int SSL_CTX_sess_connect(const SSL_CTX *ctx);
4484 
4485 // SSL_CTX_sess_connect_good returns zero.
4486 OPENSSL_EXPORT int SSL_CTX_sess_connect_good(const SSL_CTX *ctx);
4487 
4488 // SSL_CTX_sess_connect_renegotiate returns zero.
4489 OPENSSL_EXPORT int SSL_CTX_sess_connect_renegotiate(const SSL_CTX *ctx);
4490 
4491 // SSL_CTX_sess_accept returns zero.
4492 OPENSSL_EXPORT int SSL_CTX_sess_accept(const SSL_CTX *ctx);
4493 
4494 // SSL_CTX_sess_accept_renegotiate returns zero.
4495 OPENSSL_EXPORT int SSL_CTX_sess_accept_renegotiate(const SSL_CTX *ctx);
4496 
4497 // SSL_CTX_sess_accept_good returns zero.
4498 OPENSSL_EXPORT int SSL_CTX_sess_accept_good(const SSL_CTX *ctx);
4499 
4500 // SSL_CTX_sess_hits returns zero.
4501 OPENSSL_EXPORT int SSL_CTX_sess_hits(const SSL_CTX *ctx);
4502 
4503 // SSL_CTX_sess_cb_hits returns zero.
4504 OPENSSL_EXPORT int SSL_CTX_sess_cb_hits(const SSL_CTX *ctx);
4505 
4506 // SSL_CTX_sess_misses returns zero.
4507 OPENSSL_EXPORT int SSL_CTX_sess_misses(const SSL_CTX *ctx);
4508 
4509 // SSL_CTX_sess_timeouts returns zero.
4510 OPENSSL_EXPORT int SSL_CTX_sess_timeouts(const SSL_CTX *ctx);
4511 
4512 // SSL_CTX_sess_cache_full returns zero.
4513 OPENSSL_EXPORT int SSL_CTX_sess_cache_full(const SSL_CTX *ctx);
4514 
4515 // SSL_cutthrough_complete calls |SSL_in_false_start|.
4516 OPENSSL_EXPORT int SSL_cutthrough_complete(const SSL *ssl);
4517 
4518 // SSL_num_renegotiations calls |SSL_total_renegotiations|.
4519 OPENSSL_EXPORT int SSL_num_renegotiations(const SSL *ssl);
4520 
4521 // SSL_CTX_need_tmp_RSA returns zero.
4522 OPENSSL_EXPORT int SSL_CTX_need_tmp_RSA(const SSL_CTX *ctx);
4523 
4524 // SSL_need_tmp_RSA returns zero.
4525 OPENSSL_EXPORT int SSL_need_tmp_RSA(const SSL *ssl);
4526 
4527 // SSL_CTX_set_tmp_rsa returns one.
4528 OPENSSL_EXPORT int SSL_CTX_set_tmp_rsa(SSL_CTX *ctx, const RSA *rsa);
4529 
4530 // SSL_set_tmp_rsa returns one.
4531 OPENSSL_EXPORT int SSL_set_tmp_rsa(SSL *ssl, const RSA *rsa);
4532 
4533 // SSL_CTX_get_read_ahead returns zero.
4534 OPENSSL_EXPORT int SSL_CTX_get_read_ahead(const SSL_CTX *ctx);
4535 
4536 // SSL_CTX_set_read_ahead returns one.
4537 OPENSSL_EXPORT int SSL_CTX_set_read_ahead(SSL_CTX *ctx, int yes);
4538 
4539 // SSL_get_read_ahead returns zero.
4540 OPENSSL_EXPORT int SSL_get_read_ahead(const SSL *ssl);
4541 
4542 // SSL_set_read_ahead returns one.
4543 OPENSSL_EXPORT int SSL_set_read_ahead(SSL *ssl, int yes);
4544 
4545 // SSL_set_state does nothing.
4546 OPENSSL_EXPORT void SSL_set_state(SSL *ssl, int state);
4547 
4548 // SSL_get_shared_ciphers writes an empty string to |buf| and returns a
4549 // pointer to |buf|, or NULL if |len| is less than or equal to zero.
4550 OPENSSL_EXPORT char *SSL_get_shared_ciphers(const SSL *ssl, char *buf, int len);
4551 
4552 // SSL_get_shared_sigalgs returns zero.
4553 OPENSSL_EXPORT int SSL_get_shared_sigalgs(SSL *ssl, int idx, int *psign,
4554                                           int *phash, int *psignandhash,
4555                                           uint8_t *rsig, uint8_t *rhash);
4556 
4557 // SSL_MODE_HANDSHAKE_CUTTHROUGH is the same as SSL_MODE_ENABLE_FALSE_START.
4558 #define SSL_MODE_HANDSHAKE_CUTTHROUGH SSL_MODE_ENABLE_FALSE_START
4559 
4560 // i2d_SSL_SESSION serializes |in| to the bytes pointed to by |*pp|. On success,
4561 // it returns the number of bytes written and advances |*pp| by that many bytes.
4562 // On failure, it returns -1. If |pp| is NULL, no bytes are written and only the
4563 // length is returned.
4564 //
4565 // Use |SSL_SESSION_to_bytes| instead.
4566 OPENSSL_EXPORT int i2d_SSL_SESSION(SSL_SESSION *in, uint8_t **pp);
4567 
4568 // d2i_SSL_SESSION parses a serialized session from the |length| bytes pointed
4569 // to by |*pp|. It returns the new |SSL_SESSION| and advances |*pp| by the
4570 // number of bytes consumed on success and NULL on failure. The caller takes
4571 // ownership of the new session and must call |SSL_SESSION_free| when done.
4572 //
4573 // If |a| is non-NULL, |*a| is released and set the new |SSL_SESSION|.
4574 //
4575 // Use |SSL_SESSION_from_bytes| instead.
4576 OPENSSL_EXPORT SSL_SESSION *d2i_SSL_SESSION(SSL_SESSION **a, const uint8_t **pp,
4577                                             long length);
4578 
4579 // i2d_SSL_SESSION_bio serializes |session| and writes the result to |bio|. It
4580 // returns the number of bytes written on success and <= 0 on error.
4581 OPENSSL_EXPORT int i2d_SSL_SESSION_bio(BIO *bio, const SSL_SESSION *session);
4582 
4583 // d2i_SSL_SESSION_bio reads a serialized |SSL_SESSION| from |bio| and returns a
4584 // newly-allocated |SSL_SESSION| or NULL on error. If |out| is not NULL, it also
4585 // frees |*out| and sets |*out| to the new |SSL_SESSION|.
4586 OPENSSL_EXPORT SSL_SESSION *d2i_SSL_SESSION_bio(BIO *bio, SSL_SESSION **out);
4587 
4588 // ERR_load_SSL_strings does nothing.
4589 OPENSSL_EXPORT void ERR_load_SSL_strings(void);
4590 
4591 // SSL_load_error_strings does nothing.
4592 OPENSSL_EXPORT void SSL_load_error_strings(void);
4593 
4594 // SSL_CTX_set_tlsext_use_srtp calls |SSL_CTX_set_srtp_profiles|. It returns
4595 // zero on success and one on failure.
4596 //
4597 // WARNING: this function is dangerous because it breaks the usual return value
4598 // convention. Use |SSL_CTX_set_srtp_profiles| instead.
4599 OPENSSL_EXPORT int SSL_CTX_set_tlsext_use_srtp(SSL_CTX *ctx,
4600                                                const char *profiles);
4601 
4602 // SSL_set_tlsext_use_srtp calls |SSL_set_srtp_profiles|. It returns zero on
4603 // success and one on failure.
4604 //
4605 // WARNING: this function is dangerous because it breaks the usual return value
4606 // convention. Use |SSL_set_srtp_profiles| instead.
4607 OPENSSL_EXPORT int SSL_set_tlsext_use_srtp(SSL *ssl, const char *profiles);
4608 
4609 // SSL_get_current_compression returns NULL.
4610 OPENSSL_EXPORT const COMP_METHOD *SSL_get_current_compression(SSL *ssl);
4611 
4612 // SSL_get_current_expansion returns NULL.
4613 OPENSSL_EXPORT const COMP_METHOD *SSL_get_current_expansion(SSL *ssl);
4614 
4615 // SSL_get_server_tmp_key returns zero.
4616 OPENSSL_EXPORT int SSL_get_server_tmp_key(SSL *ssl, EVP_PKEY **out_key);
4617 
4618 // SSL_CTX_set_tmp_dh returns 1.
4619 OPENSSL_EXPORT int SSL_CTX_set_tmp_dh(SSL_CTX *ctx, const DH *dh);
4620 
4621 // SSL_set_tmp_dh returns 1.
4622 OPENSSL_EXPORT int SSL_set_tmp_dh(SSL *ssl, const DH *dh);
4623 
4624 // SSL_CTX_set_tmp_dh_callback does nothing.
4625 OPENSSL_EXPORT void SSL_CTX_set_tmp_dh_callback(
4626     SSL_CTX *ctx, DH *(*cb)(SSL *ssl, int is_export, int keylength));
4627 
4628 // SSL_set_tmp_dh_callback does nothing.
4629 OPENSSL_EXPORT void SSL_set_tmp_dh_callback(SSL *ssl,
4630                                             DH *(*cb)(SSL *ssl, int is_export,
4631                                                       int keylength));
4632 
4633 // SSL_CTX_set1_sigalgs takes |num_values| ints and interprets them as pairs
4634 // where the first is the nid of a hash function and the second is an
4635 // |EVP_PKEY_*| value. It configures the signature algorithm preferences for
4636 // |ctx| based on them and returns one on success or zero on error.
4637 //
4638 // This API is compatible with OpenSSL. However, BoringSSL-specific code should
4639 // prefer |SSL_CTX_set_signing_algorithm_prefs| because it's clearer and it's
4640 // more convenient to codesearch for specific algorithm values.
4641 OPENSSL_EXPORT int SSL_CTX_set1_sigalgs(SSL_CTX *ctx, const int *values,
4642                                         size_t num_values);
4643 
4644 // SSL_set1_sigalgs takes |num_values| ints and interprets them as pairs where
4645 // the first is the nid of a hash function and the second is an |EVP_PKEY_*|
4646 // value. It configures the signature algorithm preferences for |ssl| based on
4647 // them and returns one on success or zero on error.
4648 //
4649 // This API is compatible with OpenSSL. However, BoringSSL-specific code should
4650 // prefer |SSL_CTX_set_signing_algorithm_prefs| because it's clearer and it's
4651 // more convenient to codesearch for specific algorithm values.
4652 OPENSSL_EXPORT int SSL_set1_sigalgs(SSL *ssl, const int *values,
4653                                     size_t num_values);
4654 
4655 // SSL_CTX_set1_sigalgs_list takes a textual specification of a set of signature
4656 // algorithms and configures them on |ctx|. It returns one on success and zero
4657 // on error. See
4658 // https://www.openssl.org/docs/man1.1.0/man3/SSL_CTX_set1_sigalgs_list.html for
4659 // a description of the text format. Also note that TLS 1.3 names (e.g.
4660 // "rsa_pkcs1_md5_sha1") can also be used (as in OpenSSL, although OpenSSL
4661 // doesn't document that).
4662 //
4663 // This API is compatible with OpenSSL. However, BoringSSL-specific code should
4664 // prefer |SSL_CTX_set_signing_algorithm_prefs| because it's clearer and it's
4665 // more convenient to codesearch for specific algorithm values.
4666 OPENSSL_EXPORT int SSL_CTX_set1_sigalgs_list(SSL_CTX *ctx, const char *str);
4667 
4668 // SSL_set1_sigalgs_list takes a textual specification of a set of signature
4669 // algorithms and configures them on |ssl|. It returns one on success and zero
4670 // on error. See
4671 // https://www.openssl.org/docs/man1.1.0/man3/SSL_CTX_set1_sigalgs_list.html for
4672 // a description of the text format. Also note that TLS 1.3 names (e.g.
4673 // "rsa_pkcs1_md5_sha1") can also be used (as in OpenSSL, although OpenSSL
4674 // doesn't document that).
4675 //
4676 // This API is compatible with OpenSSL. However, BoringSSL-specific code should
4677 // prefer |SSL_CTX_set_signing_algorithm_prefs| because it's clearer and it's
4678 // more convenient to codesearch for specific algorithm values.
4679 OPENSSL_EXPORT int SSL_set1_sigalgs_list(SSL *ssl, const char *str);
4680 
4681 #define SSL_set_app_data(s, arg) (SSL_set_ex_data(s, 0, (char *)(arg)))
4682 #define SSL_get_app_data(s) (SSL_get_ex_data(s, 0))
4683 #define SSL_SESSION_set_app_data(s, a) \
4684   (SSL_SESSION_set_ex_data(s, 0, (char *)(a)))
4685 #define SSL_SESSION_get_app_data(s) (SSL_SESSION_get_ex_data(s, 0))
4686 #define SSL_CTX_get_app_data(ctx) (SSL_CTX_get_ex_data(ctx, 0))
4687 #define SSL_CTX_set_app_data(ctx, arg) \
4688   (SSL_CTX_set_ex_data(ctx, 0, (char *)(arg)))
4689 
4690 #define OpenSSL_add_ssl_algorithms() SSL_library_init()
4691 #define SSLeay_add_ssl_algorithms() SSL_library_init()
4692 
4693 #define SSL_get_cipher(ssl) SSL_CIPHER_get_name(SSL_get_current_cipher(ssl))
4694 #define SSL_get_cipher_bits(ssl, out_alg_bits) \
4695     SSL_CIPHER_get_bits(SSL_get_current_cipher(ssl), out_alg_bits)
4696 #define SSL_get_cipher_version(ssl) \
4697     SSL_CIPHER_get_version(SSL_get_current_cipher(ssl))
4698 #define SSL_get_cipher_name(ssl) \
4699     SSL_CIPHER_get_name(SSL_get_current_cipher(ssl))
4700 #define SSL_get_time(session) SSL_SESSION_get_time(session)
4701 #define SSL_set_time(session, time) SSL_SESSION_set_time((session), (time))
4702 #define SSL_get_timeout(session) SSL_SESSION_get_timeout(session)
4703 #define SSL_set_timeout(session, timeout) \
4704     SSL_SESSION_set_timeout((session), (timeout))
4705 
4706 struct ssl_comp_st {
4707   int id;
4708   const char *name;
4709   char *method;
4710 };
4711 
4712 DEFINE_STACK_OF(SSL_COMP)
4713 
4714 // The following flags do nothing and are included only to make it easier to
4715 // compile code with BoringSSL.
4716 #define SSL_MODE_AUTO_RETRY 0
4717 #define SSL_MODE_RELEASE_BUFFERS 0
4718 #define SSL_MODE_SEND_CLIENTHELLO_TIME 0
4719 #define SSL_MODE_SEND_SERVERHELLO_TIME 0
4720 #define SSL_OP_ALL 0
4721 #define SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION 0
4722 #define SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS 0
4723 #define SSL_OP_EPHEMERAL_RSA 0
4724 #define SSL_OP_LEGACY_SERVER_CONNECT 0
4725 #define SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER 0
4726 #define SSL_OP_MICROSOFT_SESS_ID_BUG 0
4727 #define SSL_OP_MSIE_SSLV2_RSA_PADDING 0
4728 #define SSL_OP_NETSCAPE_CA_DN_BUG 0
4729 #define SSL_OP_NETSCAPE_CHALLENGE_BUG 0
4730 #define SSL_OP_NETSCAPE_DEMO_CIPHER_CHANGE_BUG 0
4731 #define SSL_OP_NETSCAPE_REUSE_CIPHER_CHANGE_BUG 0
4732 #define SSL_OP_NO_COMPRESSION 0
4733 #define SSL_OP_NO_RENEGOTIATION 0  // ssl_renegotiate_never is the default
4734 #define SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION 0
4735 #define SSL_OP_NO_SSLv2 0
4736 #define SSL_OP_NO_SSLv3 0
4737 #define SSL_OP_PKCS1_CHECK_1 0
4738 #define SSL_OP_PKCS1_CHECK_2 0
4739 #define SSL_OP_SINGLE_DH_USE 0
4740 #define SSL_OP_SINGLE_ECDH_USE 0
4741 #define SSL_OP_SSLEAY_080_CLIENT_DH_BUG 0
4742 #define SSL_OP_SSLREF2_REUSE_CERT_TYPE_BUG 0
4743 #define SSL_OP_TLS_BLOCK_PADDING_BUG 0
4744 #define SSL_OP_TLS_D5_BUG 0
4745 #define SSL_OP_TLS_ROLLBACK_BUG 0
4746 #define SSL_VERIFY_CLIENT_ONCE 0
4747 
4748 // SSL_cache_hit calls |SSL_session_reused|.
4749 OPENSSL_EXPORT int SSL_cache_hit(SSL *ssl);
4750 
4751 // SSL_get_default_timeout returns |SSL_DEFAULT_SESSION_TIMEOUT|.
4752 OPENSSL_EXPORT long SSL_get_default_timeout(const SSL *ssl);
4753 
4754 // SSL_get_version returns a string describing the TLS version used by |ssl|.
4755 // For example, "TLSv1.2" or "DTLSv1".
4756 OPENSSL_EXPORT const char *SSL_get_version(const SSL *ssl);
4757 
4758 // SSL_get_cipher_list returns the name of the |n|th cipher in the output of
4759 // |SSL_get_ciphers| or NULL if out of range. Use |SSL_get_ciphers| instead.
4760 OPENSSL_EXPORT const char *SSL_get_cipher_list(const SSL *ssl, int n);
4761 
4762 // SSL_CTX_set_client_cert_cb sets a callback which is called on the client if
4763 // the server requests a client certificate and none is configured. On success,
4764 // the callback should return one and set |*out_x509| to |*out_pkey| to a leaf
4765 // certificate and private key, respectively, passing ownership. It should
4766 // return zero to send no certificate and -1 to fail or pause the handshake. If
4767 // the handshake is paused, |SSL_get_error| will return
4768 // |SSL_ERROR_WANT_X509_LOOKUP|.
4769 //
4770 // The callback may call |SSL_get0_certificate_types| and
4771 // |SSL_get_client_CA_list| for information on the server's certificate request.
4772 //
4773 // Use |SSL_CTX_set_cert_cb| instead. Configuring intermediate certificates with
4774 // this function is confusing. This callback may not be registered concurrently
4775 // with |SSL_CTX_set_cert_cb| or |SSL_set_cert_cb|.
4776 OPENSSL_EXPORT void SSL_CTX_set_client_cert_cb(
4777     SSL_CTX *ctx, int (*cb)(SSL *ssl, X509 **out_x509, EVP_PKEY **out_pkey));
4778 
4779 #define SSL_NOTHING SSL_ERROR_NONE
4780 #define SSL_WRITING SSL_ERROR_WANT_WRITE
4781 #define SSL_READING SSL_ERROR_WANT_READ
4782 
4783 // SSL_want returns one of the above values to determine what the most recent
4784 // operation on |ssl| was blocked on. Use |SSL_get_error| instead.
4785 OPENSSL_EXPORT int SSL_want(const SSL *ssl);
4786 
4787 #define SSL_want_read(ssl) (SSL_want(ssl) == SSL_READING)
4788 #define SSL_want_write(ssl) (SSL_want(ssl) == SSL_WRITING)
4789 
4790  // SSL_get_finished writes up to |count| bytes of the Finished message sent by
4791  // |ssl| to |buf|. It returns the total untruncated length or zero if none has
4792  // been sent yet. At TLS 1.3 and later, it returns zero.
4793  //
4794  // Use |SSL_get_tls_unique| instead.
4795 OPENSSL_EXPORT size_t SSL_get_finished(const SSL *ssl, void *buf, size_t count);
4796 
4797  // SSL_get_peer_finished writes up to |count| bytes of the Finished message
4798  // received from |ssl|'s peer to |buf|. It returns the total untruncated length
4799  // or zero if none has been received yet. At TLS 1.3 and later, it returns
4800  // zero.
4801  //
4802  // Use |SSL_get_tls_unique| instead.
4803 OPENSSL_EXPORT size_t SSL_get_peer_finished(const SSL *ssl, void *buf,
4804                                             size_t count);
4805 
4806 // SSL_alert_type_string returns "!". Use |SSL_alert_type_string_long|
4807 // instead.
4808 OPENSSL_EXPORT const char *SSL_alert_type_string(int value);
4809 
4810 // SSL_alert_desc_string returns "!!". Use |SSL_alert_desc_string_long|
4811 // instead.
4812 OPENSSL_EXPORT const char *SSL_alert_desc_string(int value);
4813 
4814 // SSL_state_string returns "!!!!!!". Use |SSL_state_string_long| for a more
4815 // intelligible string.
4816 OPENSSL_EXPORT const char *SSL_state_string(const SSL *ssl);
4817 
4818 // SSL_TXT_* expand to strings.
4819 #define SSL_TXT_MEDIUM "MEDIUM"
4820 #define SSL_TXT_HIGH "HIGH"
4821 #define SSL_TXT_FIPS "FIPS"
4822 #define SSL_TXT_kRSA "kRSA"
4823 #define SSL_TXT_kDHE "kDHE"
4824 #define SSL_TXT_kEDH "kEDH"
4825 #define SSL_TXT_kECDHE "kECDHE"
4826 #define SSL_TXT_kEECDH "kEECDH"
4827 #define SSL_TXT_kPSK "kPSK"
4828 #define SSL_TXT_aRSA "aRSA"
4829 #define SSL_TXT_aECDSA "aECDSA"
4830 #define SSL_TXT_aPSK "aPSK"
4831 #define SSL_TXT_DH "DH"
4832 #define SSL_TXT_DHE "DHE"
4833 #define SSL_TXT_EDH "EDH"
4834 #define SSL_TXT_RSA "RSA"
4835 #define SSL_TXT_ECDH "ECDH"
4836 #define SSL_TXT_ECDHE "ECDHE"
4837 #define SSL_TXT_EECDH "EECDH"
4838 #define SSL_TXT_ECDSA "ECDSA"
4839 #define SSL_TXT_PSK "PSK"
4840 #define SSL_TXT_3DES "3DES"
4841 #define SSL_TXT_RC4 "RC4"
4842 #define SSL_TXT_AES128 "AES128"
4843 #define SSL_TXT_AES256 "AES256"
4844 #define SSL_TXT_AES "AES"
4845 #define SSL_TXT_AES_GCM "AESGCM"
4846 #define SSL_TXT_CHACHA20 "CHACHA20"
4847 #define SSL_TXT_MD5 "MD5"
4848 #define SSL_TXT_SHA1 "SHA1"
4849 #define SSL_TXT_SHA "SHA"
4850 #define SSL_TXT_SHA256 "SHA256"
4851 #define SSL_TXT_SHA384 "SHA384"
4852 #define SSL_TXT_SSLV3 "SSLv3"
4853 #define SSL_TXT_TLSV1 "TLSv1"
4854 #define SSL_TXT_TLSV1_1 "TLSv1.1"
4855 #define SSL_TXT_TLSV1_2 "TLSv1.2"
4856 #define SSL_TXT_TLSV1_3 "TLSv1.3"
4857 #define SSL_TXT_ALL "ALL"
4858 #define SSL_TXT_CMPDEF "COMPLEMENTOFDEFAULT"
4859 
4860 typedef struct ssl_conf_ctx_st SSL_CONF_CTX;
4861 
4862 // SSL_state returns |SSL_ST_INIT| if a handshake is in progress and |SSL_ST_OK|
4863 // otherwise.
4864 //
4865 // Use |SSL_is_init| instead.
4866 OPENSSL_EXPORT int SSL_state(const SSL *ssl);
4867 
4868 #define SSL_get_state(ssl) SSL_state(ssl)
4869 
4870 // SSL_set_shutdown causes |ssl| to behave as if the shutdown bitmask (see
4871 // |SSL_get_shutdown|) were |mode|. This may be used to skip sending or
4872 // receiving close_notify in |SSL_shutdown| by causing the implementation to
4873 // believe the events already happened.
4874 //
4875 // It is an error to use |SSL_set_shutdown| to unset a bit that has already been
4876 // set. Doing so will trigger an |assert| in debug builds and otherwise be
4877 // ignored.
4878 //
4879 // Use |SSL_CTX_set_quiet_shutdown| instead.
4880 OPENSSL_EXPORT void SSL_set_shutdown(SSL *ssl, int mode);
4881 
4882 // SSL_CTX_set_tmp_ecdh calls |SSL_CTX_set1_curves| with a one-element list
4883 // containing |ec_key|'s curve.
4884 OPENSSL_EXPORT int SSL_CTX_set_tmp_ecdh(SSL_CTX *ctx, const EC_KEY *ec_key);
4885 
4886 // SSL_set_tmp_ecdh calls |SSL_set1_curves| with a one-element list containing
4887 // |ec_key|'s curve.
4888 OPENSSL_EXPORT int SSL_set_tmp_ecdh(SSL *ssl, const EC_KEY *ec_key);
4889 
4890 // SSL_add_dir_cert_subjects_to_stack lists files in directory |dir|. It calls
4891 // |SSL_add_file_cert_subjects_to_stack| on each file and returns one on success
4892 // or zero on error. This function is only available from the libdecrepit
4893 // library.
4894 OPENSSL_EXPORT int SSL_add_dir_cert_subjects_to_stack(STACK_OF(X509_NAME) *out,
4895                                                       const char *dir);
4896 
4897 // SSL_CTX_enable_tls_channel_id calls |SSL_CTX_set_tls_channel_id_enabled|.
4898 OPENSSL_EXPORT int SSL_CTX_enable_tls_channel_id(SSL_CTX *ctx);
4899 
4900 // SSL_enable_tls_channel_id calls |SSL_set_tls_channel_id_enabled|.
4901 OPENSSL_EXPORT int SSL_enable_tls_channel_id(SSL *ssl);
4902 
4903 // BIO_f_ssl returns a |BIO_METHOD| that can wrap an |SSL*| in a |BIO*|. Note
4904 // that this has quite different behaviour from the version in OpenSSL (notably
4905 // that it doesn't try to auto renegotiate).
4906 //
4907 // IMPORTANT: if you are not curl, don't use this.
4908 OPENSSL_EXPORT const BIO_METHOD *BIO_f_ssl(void);
4909 
4910 // BIO_set_ssl sets |ssl| as the underlying connection for |bio|, which must
4911 // have been created using |BIO_f_ssl|. If |take_owership| is true, |bio| will
4912 // call |SSL_free| on |ssl| when closed. It returns one on success or something
4913 // other than one on error.
4914 OPENSSL_EXPORT long BIO_set_ssl(BIO *bio, SSL *ssl, int take_owership);
4915 
4916 // SSL_CTX_set_ecdh_auto returns one.
4917 #define SSL_CTX_set_ecdh_auto(ctx, onoff) 1
4918 
4919 // SSL_set_ecdh_auto returns one.
4920 #define SSL_set_ecdh_auto(ssl, onoff) 1
4921 
4922 // SSL_get_session returns a non-owning pointer to |ssl|'s session. For
4923 // historical reasons, which session it returns depends on |ssl|'s state.
4924 //
4925 // Prior to the start of the initial handshake, it returns the session the
4926 // caller set with |SSL_set_session|. After the initial handshake has finished
4927 // and if no additional handshakes are in progress, it returns the currently
4928 // active session. Its behavior is undefined while a handshake is in progress.
4929 //
4930 // If trying to add new sessions to an external session cache, use
4931 // |SSL_CTX_sess_set_new_cb| instead. In particular, using the callback is
4932 // required as of TLS 1.3. For compatibility, this function will return an
4933 // unresumable session which may be cached, but will never be resumed.
4934 //
4935 // If querying properties of the connection, use APIs on the |SSL| object.
4936 OPENSSL_EXPORT SSL_SESSION *SSL_get_session(const SSL *ssl);
4937 
4938 // SSL_get0_session is an alias for |SSL_get_session|.
4939 #define SSL_get0_session SSL_get_session
4940 
4941 // SSL_get1_session acts like |SSL_get_session| but returns a new reference to
4942 // the session.
4943 OPENSSL_EXPORT SSL_SESSION *SSL_get1_session(SSL *ssl);
4944 
4945 #define OPENSSL_INIT_NO_LOAD_SSL_STRINGS 0
4946 #define OPENSSL_INIT_LOAD_SSL_STRINGS 0
4947 #define OPENSSL_INIT_SSL_DEFAULT 0
4948 
4949 // OPENSSL_init_ssl calls |CRYPTO_library_init| and returns one.
4950 OPENSSL_EXPORT int OPENSSL_init_ssl(uint64_t opts,
4951                                     const OPENSSL_INIT_SETTINGS *settings);
4952 
4953 // The following constants are legacy aliases for RSA-PSS with rsaEncryption
4954 // keys. Use the new names instead.
4955 #define SSL_SIGN_RSA_PSS_SHA256 SSL_SIGN_RSA_PSS_RSAE_SHA256
4956 #define SSL_SIGN_RSA_PSS_SHA384 SSL_SIGN_RSA_PSS_RSAE_SHA384
4957 #define SSL_SIGN_RSA_PSS_SHA512 SSL_SIGN_RSA_PSS_RSAE_SHA512
4958 
4959 // SSL_set_tlsext_status_type configures a client to request OCSP stapling if
4960 // |type| is |TLSEXT_STATUSTYPE_ocsp| and disables it otherwise. It returns one
4961 // on success and zero if handshake configuration has already been shed.
4962 //
4963 // Use |SSL_enable_ocsp_stapling| instead.
4964 OPENSSL_EXPORT int SSL_set_tlsext_status_type(SSL *ssl, int type);
4965 
4966 // SSL_get_tlsext_status_type returns |TLSEXT_STATUSTYPE_ocsp| if the client
4967 // requested OCSP stapling and |TLSEXT_STATUSTYPE_nothing| otherwise. On the
4968 // client, this reflects whether OCSP stapling was enabled via, e.g.,
4969 // |SSL_set_tlsext_status_type|. On the server, this is determined during the
4970 // handshake. It may be queried in callbacks set by |SSL_CTX_set_cert_cb|. The
4971 // result is undefined after the handshake completes.
4972 OPENSSL_EXPORT int SSL_get_tlsext_status_type(const SSL *ssl);
4973 
4974 // SSL_set_tlsext_status_ocsp_resp sets the OCSP response. It returns one on
4975 // success and zero on error. On success, |ssl| takes ownership of |resp|, which
4976 // must have been allocated by |OPENSSL_malloc|.
4977 //
4978 // Use |SSL_set_ocsp_response| instead.
4979 OPENSSL_EXPORT int SSL_set_tlsext_status_ocsp_resp(SSL *ssl, uint8_t *resp,
4980                                                    size_t resp_len);
4981 
4982 // SSL_get_tlsext_status_ocsp_resp sets |*out| to point to the OCSP response
4983 // from the server. It returns the length of the response. If there was no
4984 // response, it sets |*out| to NULL and returns zero.
4985 //
4986 // Use |SSL_get0_ocsp_response| instead.
4987 //
4988 // WARNING: the returned data is not guaranteed to be well formed.
4989 OPENSSL_EXPORT size_t SSL_get_tlsext_status_ocsp_resp(const SSL *ssl,
4990                                                       const uint8_t **out);
4991 
4992 // SSL_CTX_set_tlsext_status_cb configures the legacy OpenSSL OCSP callback and
4993 // returns one. Though the type signature is the same, this callback has
4994 // different behavior for client and server connections:
4995 //
4996 // For clients, the callback is called after certificate verification. It should
4997 // return one for success, zero for a bad OCSP response, and a negative number
4998 // for internal error. Instead, handle this as part of certificate verification.
4999 // (Historically, OpenSSL verified certificates just before parsing stapled OCSP
5000 // responses, but BoringSSL fixes this ordering. All server credentials are
5001 // available during verification.)
5002 //
5003 // Do not use this callback as a server. It is provided for compatibility
5004 // purposes only. For servers, it is called to configure server credentials. It
5005 // should return |SSL_TLSEXT_ERR_OK| on success, |SSL_TLSEXT_ERR_NOACK| to
5006 // ignore OCSP requests, or |SSL_TLSEXT_ERR_ALERT_FATAL| on error. It is usually
5007 // used to fetch OCSP responses on demand, which is not ideal. Instead, treat
5008 // OCSP responses like other server credentials, such as certificates or SCT
5009 // lists. Configure, store, and refresh them eagerly. This avoids downtime if
5010 // the CA's OCSP responder is briefly offline.
5011 OPENSSL_EXPORT int SSL_CTX_set_tlsext_status_cb(SSL_CTX *ctx,
5012                                                 int (*callback)(SSL *ssl,
5013                                                                 void *arg));
5014 
5015 // SSL_CTX_set_tlsext_status_arg sets additional data for
5016 // |SSL_CTX_set_tlsext_status_cb|'s callback and returns one.
5017 OPENSSL_EXPORT int SSL_CTX_set_tlsext_status_arg(SSL_CTX *ctx, void *arg);
5018 
5019 // The following symbols are compatibility aliases for reason codes used when
5020 // receiving an alert from the peer. Use the other names instead, which fit the
5021 // naming convention.
5022 //
5023 // TODO(davidben): Fix references to |SSL_R_TLSV1_CERTIFICATE_REQUIRED| and
5024 // remove the compatibility value. The others come from OpenSSL.
5025 #define SSL_R_TLSV1_UNSUPPORTED_EXTENSION \
5026   SSL_R_TLSV1_ALERT_UNSUPPORTED_EXTENSION
5027 #define SSL_R_TLSV1_CERTIFICATE_UNOBTAINABLE \
5028   SSL_R_TLSV1_ALERT_CERTIFICATE_UNOBTAINABLE
5029 #define SSL_R_TLSV1_UNRECOGNIZED_NAME SSL_R_TLSV1_ALERT_UNRECOGNIZED_NAME
5030 #define SSL_R_TLSV1_BAD_CERTIFICATE_STATUS_RESPONSE \
5031   SSL_R_TLSV1_ALERT_BAD_CERTIFICATE_STATUS_RESPONSE
5032 #define SSL_R_TLSV1_BAD_CERTIFICATE_HASH_VALUE \
5033   SSL_R_TLSV1_ALERT_BAD_CERTIFICATE_HASH_VALUE
5034 #define SSL_R_TLSV1_CERTIFICATE_REQUIRED SSL_R_TLSV1_ALERT_CERTIFICATE_REQUIRED
5035 
5036 // SSL_CIPHER_get_value calls |SSL_CIPHER_get_protocol_id|.
5037 //
5038 // TODO(davidben): |SSL_CIPHER_get_value| was our name for this function, but
5039 // upstream added it as |SSL_CIPHER_get_protocol_id|. Switch callers to the new
5040 // name and remove this one.
5041 OPENSSL_EXPORT uint16_t SSL_CIPHER_get_value(const SSL_CIPHER *cipher);
5042 
5043 
5044 // Nodejs compatibility section (hidden).
5045 //
5046 // These defines exist for node.js, with the hope that we can eliminate the
5047 // need for them over time.
5048 
5049 #define SSLerr(function, reason) \
5050   ERR_put_error(ERR_LIB_SSL, 0, reason, __FILE__, __LINE__)
5051 
5052 
5053 // Preprocessor compatibility section (hidden).
5054 //
5055 // Historically, a number of APIs were implemented in OpenSSL as macros and
5056 // constants to 'ctrl' functions. To avoid breaking #ifdefs in consumers, this
5057 // section defines a number of legacy macros.
5058 //
5059 // Although using either the CTRL values or their wrapper macros in #ifdefs is
5060 // still supported, the CTRL values may not be passed to |SSL_ctrl| and
5061 // |SSL_CTX_ctrl|. Call the functions (previously wrapper macros) instead.
5062 //
5063 // See PORTING.md in the BoringSSL source tree for a table of corresponding
5064 // functions.
5065 // https://boringssl.googlesource.com/boringssl/+/master/PORTING.md#Replacements-for-values
5066 
5067 #define DTLS_CTRL_GET_TIMEOUT doesnt_exist
5068 #define DTLS_CTRL_HANDLE_TIMEOUT doesnt_exist
5069 #define SSL_CTRL_CHAIN doesnt_exist
5070 #define SSL_CTRL_CHAIN_CERT doesnt_exist
5071 #define SSL_CTRL_CHANNEL_ID doesnt_exist
5072 #define SSL_CTRL_CLEAR_EXTRA_CHAIN_CERTS doesnt_exist
5073 #define SSL_CTRL_CLEAR_MODE doesnt_exist
5074 #define SSL_CTRL_CLEAR_OPTIONS doesnt_exist
5075 #define SSL_CTRL_EXTRA_CHAIN_CERT doesnt_exist
5076 #define SSL_CTRL_GET_CHAIN_CERTS doesnt_exist
5077 #define SSL_CTRL_GET_CHANNEL_ID doesnt_exist
5078 #define SSL_CTRL_GET_CLIENT_CERT_TYPES doesnt_exist
5079 #define SSL_CTRL_GET_EXTRA_CHAIN_CERTS doesnt_exist
5080 #define SSL_CTRL_GET_MAX_CERT_LIST doesnt_exist
5081 #define SSL_CTRL_GET_NUM_RENEGOTIATIONS doesnt_exist
5082 #define SSL_CTRL_GET_READ_AHEAD doesnt_exist
5083 #define SSL_CTRL_GET_RI_SUPPORT doesnt_exist
5084 #define SSL_CTRL_GET_SERVER_TMP_KEY doesnt_exist
5085 #define SSL_CTRL_GET_SESSION_REUSED doesnt_exist
5086 #define SSL_CTRL_GET_SESS_CACHE_MODE doesnt_exist
5087 #define SSL_CTRL_GET_SESS_CACHE_SIZE doesnt_exist
5088 #define SSL_CTRL_GET_TLSEXT_TICKET_KEYS doesnt_exist
5089 #define SSL_CTRL_GET_TOTAL_RENEGOTIATIONS doesnt_exist
5090 #define SSL_CTRL_MODE doesnt_exist
5091 #define SSL_CTRL_NEED_TMP_RSA doesnt_exist
5092 #define SSL_CTRL_OPTIONS doesnt_exist
5093 #define SSL_CTRL_SESS_NUMBER doesnt_exist
5094 #define SSL_CTRL_SET_CURVES doesnt_exist
5095 #define SSL_CTRL_SET_CURVES_LIST doesnt_exist
5096 #define SSL_CTRL_SET_ECDH_AUTO doesnt_exist
5097 #define SSL_CTRL_SET_MAX_CERT_LIST doesnt_exist
5098 #define SSL_CTRL_SET_MAX_SEND_FRAGMENT doesnt_exist
5099 #define SSL_CTRL_SET_MSG_CALLBACK doesnt_exist
5100 #define SSL_CTRL_SET_MSG_CALLBACK_ARG doesnt_exist
5101 #define SSL_CTRL_SET_MTU doesnt_exist
5102 #define SSL_CTRL_SET_READ_AHEAD doesnt_exist
5103 #define SSL_CTRL_SET_SESS_CACHE_MODE doesnt_exist
5104 #define SSL_CTRL_SET_SESS_CACHE_SIZE doesnt_exist
5105 #define SSL_CTRL_SET_TLSEXT_HOSTNAME doesnt_exist
5106 #define SSL_CTRL_SET_TLSEXT_SERVERNAME_ARG doesnt_exist
5107 #define SSL_CTRL_SET_TLSEXT_SERVERNAME_CB doesnt_exist
5108 #define SSL_CTRL_SET_TLSEXT_TICKET_KEYS doesnt_exist
5109 #define SSL_CTRL_SET_TLSEXT_TICKET_KEY_CB doesnt_exist
5110 #define SSL_CTRL_SET_TMP_DH doesnt_exist
5111 #define SSL_CTRL_SET_TMP_DH_CB doesnt_exist
5112 #define SSL_CTRL_SET_TMP_ECDH doesnt_exist
5113 #define SSL_CTRL_SET_TMP_ECDH_CB doesnt_exist
5114 #define SSL_CTRL_SET_TMP_RSA doesnt_exist
5115 #define SSL_CTRL_SET_TMP_RSA_CB doesnt_exist
5116 
5117 // |BORINGSSL_PREFIX| already makes each of these symbols into macros, so there
5118 // is no need to define conflicting macros.
5119 #if !defined(BORINGSSL_PREFIX)
5120 
5121 #define DTLSv1_get_timeout DTLSv1_get_timeout
5122 #define DTLSv1_handle_timeout DTLSv1_handle_timeout
5123 #define SSL_CTX_add0_chain_cert SSL_CTX_add0_chain_cert
5124 #define SSL_CTX_add1_chain_cert SSL_CTX_add1_chain_cert
5125 #define SSL_CTX_add_extra_chain_cert SSL_CTX_add_extra_chain_cert
5126 #define SSL_CTX_clear_extra_chain_certs SSL_CTX_clear_extra_chain_certs
5127 #define SSL_CTX_clear_chain_certs SSL_CTX_clear_chain_certs
5128 #define SSL_CTX_clear_mode SSL_CTX_clear_mode
5129 #define SSL_CTX_clear_options SSL_CTX_clear_options
5130 #define SSL_CTX_get0_chain_certs SSL_CTX_get0_chain_certs
5131 #define SSL_CTX_get_extra_chain_certs SSL_CTX_get_extra_chain_certs
5132 #define SSL_CTX_get_max_cert_list SSL_CTX_get_max_cert_list
5133 #define SSL_CTX_get_mode SSL_CTX_get_mode
5134 #define SSL_CTX_get_options SSL_CTX_get_options
5135 #define SSL_CTX_get_read_ahead SSL_CTX_get_read_ahead
5136 #define SSL_CTX_get_session_cache_mode SSL_CTX_get_session_cache_mode
5137 #define SSL_CTX_get_tlsext_ticket_keys SSL_CTX_get_tlsext_ticket_keys
5138 #define SSL_CTX_need_tmp_RSA SSL_CTX_need_tmp_RSA
5139 #define SSL_CTX_sess_get_cache_size SSL_CTX_sess_get_cache_size
5140 #define SSL_CTX_sess_number SSL_CTX_sess_number
5141 #define SSL_CTX_sess_set_cache_size SSL_CTX_sess_set_cache_size
5142 #define SSL_CTX_set0_chain SSL_CTX_set0_chain
5143 #define SSL_CTX_set1_chain SSL_CTX_set1_chain
5144 #define SSL_CTX_set1_curves SSL_CTX_set1_curves
5145 #define SSL_CTX_set_max_cert_list SSL_CTX_set_max_cert_list
5146 #define SSL_CTX_set_max_send_fragment SSL_CTX_set_max_send_fragment
5147 #define SSL_CTX_set_mode SSL_CTX_set_mode
5148 #define SSL_CTX_set_msg_callback_arg SSL_CTX_set_msg_callback_arg
5149 #define SSL_CTX_set_options SSL_CTX_set_options
5150 #define SSL_CTX_set_read_ahead SSL_CTX_set_read_ahead
5151 #define SSL_CTX_set_session_cache_mode SSL_CTX_set_session_cache_mode
5152 #define SSL_CTX_set_tlsext_servername_arg SSL_CTX_set_tlsext_servername_arg
5153 #define SSL_CTX_set_tlsext_servername_callback \
5154     SSL_CTX_set_tlsext_servername_callback
5155 #define SSL_CTX_set_tlsext_ticket_key_cb SSL_CTX_set_tlsext_ticket_key_cb
5156 #define SSL_CTX_set_tlsext_ticket_keys SSL_CTX_set_tlsext_ticket_keys
5157 #define SSL_CTX_set_tmp_dh SSL_CTX_set_tmp_dh
5158 #define SSL_CTX_set_tmp_ecdh SSL_CTX_set_tmp_ecdh
5159 #define SSL_CTX_set_tmp_rsa SSL_CTX_set_tmp_rsa
5160 #define SSL_add0_chain_cert SSL_add0_chain_cert
5161 #define SSL_add1_chain_cert SSL_add1_chain_cert
5162 #define SSL_clear_chain_certs SSL_clear_chain_certs
5163 #define SSL_clear_mode SSL_clear_mode
5164 #define SSL_clear_options SSL_clear_options
5165 #define SSL_get0_certificate_types SSL_get0_certificate_types
5166 #define SSL_get0_chain_certs SSL_get0_chain_certs
5167 #define SSL_get_max_cert_list SSL_get_max_cert_list
5168 #define SSL_get_mode SSL_get_mode
5169 #define SSL_get_options SSL_get_options
5170 #define SSL_get_secure_renegotiation_support \
5171     SSL_get_secure_renegotiation_support
5172 #define SSL_need_tmp_RSA SSL_need_tmp_RSA
5173 #define SSL_num_renegotiations SSL_num_renegotiations
5174 #define SSL_session_reused SSL_session_reused
5175 #define SSL_set0_chain SSL_set0_chain
5176 #define SSL_set1_chain SSL_set1_chain
5177 #define SSL_set1_curves SSL_set1_curves
5178 #define SSL_set_max_cert_list SSL_set_max_cert_list
5179 #define SSL_set_max_send_fragment SSL_set_max_send_fragment
5180 #define SSL_set_mode SSL_set_mode
5181 #define SSL_set_msg_callback_arg SSL_set_msg_callback_arg
5182 #define SSL_set_mtu SSL_set_mtu
5183 #define SSL_set_options SSL_set_options
5184 #define SSL_set_tlsext_host_name SSL_set_tlsext_host_name
5185 #define SSL_set_tmp_dh SSL_set_tmp_dh
5186 #define SSL_set_tmp_ecdh SSL_set_tmp_ecdh
5187 #define SSL_set_tmp_rsa SSL_set_tmp_rsa
5188 #define SSL_total_renegotiations SSL_total_renegotiations
5189 
5190 #endif // !defined(BORINGSSL_PREFIX)
5191 
5192 
5193 #if defined(__cplusplus)
5194 }  // extern C
5195 
5196 #if !defined(BORINGSSL_NO_CXX)
5197 
5198 extern "C++" {
5199 
5200 BSSL_NAMESPACE_BEGIN
5201 
5202 BORINGSSL_MAKE_DELETER(SSL, SSL_free)
5203 BORINGSSL_MAKE_DELETER(SSL_CTX, SSL_CTX_free)
5204 BORINGSSL_MAKE_UP_REF(SSL_CTX, SSL_CTX_up_ref)
5205 BORINGSSL_MAKE_DELETER(SSL_ECH_KEYS, SSL_ECH_KEYS_free)
5206 BORINGSSL_MAKE_UP_REF(SSL_ECH_KEYS, SSL_ECH_KEYS_up_ref)
5207 BORINGSSL_MAKE_DELETER(SSL_SESSION, SSL_SESSION_free)
5208 BORINGSSL_MAKE_UP_REF(SSL_SESSION, SSL_SESSION_up_ref)
5209 
5210 enum class OpenRecordResult {
5211   kOK,
5212   kDiscard,
5213   kIncompleteRecord,
5214   kAlertCloseNotify,
5215   kError,
5216 };
5217 
5218 //  *** EXPERIMENTAL -- DO NOT USE ***
5219 //
5220 // OpenRecord decrypts the first complete SSL record from |in| in-place, sets
5221 // |out| to the decrypted application data, and |out_record_len| to the length
5222 // of the encrypted record. Returns:
5223 // - kOK if an application-data record was successfully decrypted and verified.
5224 // - kDiscard if a record was sucessfully processed, but should be discarded.
5225 // - kIncompleteRecord if |in| did not contain a complete record.
5226 // - kAlertCloseNotify if a record was successfully processed but is a
5227 //   close_notify alert.
5228 // - kError if an error occurred or the record is invalid. |*out_alert| will be
5229 //   set to an alert to emit, or zero if no alert should be emitted.
5230 OPENSSL_EXPORT OpenRecordResult OpenRecord(SSL *ssl, Span<uint8_t> *out,
5231                                            size_t *out_record_len,
5232                                            uint8_t *out_alert,
5233                                            Span<uint8_t> in);
5234 
5235 OPENSSL_EXPORT size_t SealRecordPrefixLen(const SSL *ssl, size_t plaintext_len);
5236 
5237 // SealRecordSuffixLen returns the length of the suffix written by |SealRecord|.
5238 //
5239 // |plaintext_len| must be equal to the size of the plaintext passed to
5240 // |SealRecord|.
5241 //
5242 // |plaintext_len| must not exceed |SSL3_RT_MAX_PLAINTEXT_LENGTH|. The returned
5243 // suffix length will not exceed |SSL3_RT_MAX_ENCRYPTED_OVERHEAD|.
5244 OPENSSL_EXPORT size_t SealRecordSuffixLen(const SSL *ssl, size_t plaintext_len);
5245 
5246 //  *** EXPERIMENTAL -- DO NOT USE ***
5247 //
5248 // SealRecord encrypts the cleartext of |in| and scatters the resulting TLS
5249 // application data record between |out_prefix|, |out|, and |out_suffix|. It
5250 // returns true on success or false if an error occurred.
5251 //
5252 // The length of |out_prefix| must equal |SealRecordPrefixLen|. The length of
5253 // |out| must equal the length of |in|, which must not exceed
5254 // |SSL3_RT_MAX_PLAINTEXT_LENGTH|. The length of |out_suffix| must equal
5255 // |SealRecordSuffixLen|.
5256 //
5257 // If enabled, |SealRecord| may perform TLS 1.0 CBC 1/n-1 record splitting.
5258 // |SealRecordPrefixLen| accounts for the required overhead if that is the case.
5259 //
5260 // |out| may equal |in| to encrypt in-place but may not otherwise alias.
5261 // |out_prefix| and |out_suffix| may not alias anything.
5262 OPENSSL_EXPORT bool SealRecord(SSL *ssl, Span<uint8_t> out_prefix,
5263                                Span<uint8_t> out, Span<uint8_t> out_suffix,
5264                                Span<const uint8_t> in);
5265 
5266 
5267 // *** EXPERIMENTAL — DO NOT USE WITHOUT CHECKING ***
5268 //
5269 // Split handshakes.
5270 //
5271 // Split handshakes allows the handshake part of a TLS connection to be
5272 // performed in a different process (or on a different machine) than the data
5273 // exchange. This only applies to servers.
5274 //
5275 // In the first part of a split handshake, an |SSL| (where the |SSL_CTX| has
5276 // been configured with |SSL_CTX_set_handoff_mode|) is used normally. Once the
5277 // ClientHello message has been received, the handshake will stop and
5278 // |SSL_get_error| will indicate |SSL_ERROR_HANDOFF|. At this point (and only
5279 // at this point), |SSL_serialize_handoff| can be called to write the “handoff”
5280 // state of the connection.
5281 //
5282 // Elsewhere, a fresh |SSL| can be used with |SSL_apply_handoff| to continue
5283 // the connection. The connection from the client is fed into this |SSL|, and
5284 // the handshake resumed. When the handshake stops again and |SSL_get_error|
5285 // indicates |SSL_ERROR_HANDBACK|, |SSL_serialize_handback| should be called to
5286 // serialize the state of the handshake again.
5287 //
5288 // Back at the first location, a fresh |SSL| can be used with
5289 // |SSL_apply_handback|. Then the client's connection can be processed mostly
5290 // as normal.
5291 //
5292 // Lastly, when a connection is in the handoff state, whether or not
5293 // |SSL_serialize_handoff| is called, |SSL_decline_handoff| will move it back
5294 // into a normal state where the connection can proceed without impact.
5295 //
5296 // WARNING: Currently only works with TLS 1.0–1.2.
5297 // WARNING: The serialisation formats are not yet stable: version skew may be
5298 //     fatal.
5299 // WARNING: The handback data contains sensitive key material and must be
5300 //     protected.
5301 // WARNING: Some calls on the final |SSL| will not work. Just as an example,
5302 //     calls like |SSL_get0_session_id_context| and |SSL_get_privatekey| won't
5303 //     work because the certificate used for handshaking isn't available.
5304 // WARNING: |SSL_apply_handoff| may trigger “msg” callback calls.
5305 
5306 OPENSSL_EXPORT void SSL_CTX_set_handoff_mode(SSL_CTX *ctx, bool on);
5307 OPENSSL_EXPORT void SSL_set_handoff_mode(SSL *SSL, bool on);
5308 OPENSSL_EXPORT bool SSL_serialize_handoff(const SSL *ssl, CBB *out,
5309                                           SSL_CLIENT_HELLO *out_hello);
5310 OPENSSL_EXPORT bool SSL_decline_handoff(SSL *ssl);
5311 OPENSSL_EXPORT bool SSL_apply_handoff(SSL *ssl, Span<const uint8_t> handoff);
5312 OPENSSL_EXPORT bool SSL_serialize_handback(const SSL *ssl, CBB *out);
5313 OPENSSL_EXPORT bool SSL_apply_handback(SSL *ssl, Span<const uint8_t> handback);
5314 
5315 // SSL_get_traffic_secrets sets |*out_read_traffic_secret| and
5316 // |*out_write_traffic_secret| to reference the TLS 1.3 traffic secrets for
5317 // |ssl|. This function is only valid on TLS 1.3 connections that have
5318 // completed the handshake. It returns true on success and false on error.
5319 OPENSSL_EXPORT bool SSL_get_traffic_secrets(
5320     const SSL *ssl, Span<const uint8_t> *out_read_traffic_secret,
5321     Span<const uint8_t> *out_write_traffic_secret);
5322 
5323 
5324 BSSL_NAMESPACE_END
5325 
5326 }  // extern C++
5327 
5328 #endif  // !defined(BORINGSSL_NO_CXX)
5329 
5330 #endif
5331 
5332 #define SSL_R_APP_DATA_IN_HANDSHAKE 100
5333 #define SSL_R_ATTEMPT_TO_REUSE_SESSION_IN_DIFFERENT_CONTEXT 101
5334 #define SSL_R_BAD_ALERT 102
5335 #define SSL_R_BAD_CHANGE_CIPHER_SPEC 103
5336 #define SSL_R_BAD_DATA_RETURNED_BY_CALLBACK 104
5337 #define SSL_R_BAD_DH_P_LENGTH 105
5338 #define SSL_R_BAD_DIGEST_LENGTH 106
5339 #define SSL_R_BAD_ECC_CERT 107
5340 #define SSL_R_BAD_ECPOINT 108
5341 #define SSL_R_BAD_HANDSHAKE_RECORD 109
5342 #define SSL_R_BAD_HELLO_REQUEST 110
5343 #define SSL_R_BAD_LENGTH 111
5344 #define SSL_R_BAD_PACKET_LENGTH 112
5345 #define SSL_R_BAD_RSA_ENCRYPT 113
5346 #define SSL_R_BAD_SIGNATURE 114
5347 #define SSL_R_BAD_SRTP_MKI_VALUE 115
5348 #define SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST 116
5349 #define SSL_R_BAD_SSL_FILETYPE 117
5350 #define SSL_R_BAD_WRITE_RETRY 118
5351 #define SSL_R_BIO_NOT_SET 119
5352 #define SSL_R_BN_LIB 120
5353 #define SSL_R_BUFFER_TOO_SMALL 121
5354 #define SSL_R_CA_DN_LENGTH_MISMATCH 122
5355 #define SSL_R_CA_DN_TOO_LONG 123
5356 #define SSL_R_CCS_RECEIVED_EARLY 124
5357 #define SSL_R_CERTIFICATE_VERIFY_FAILED 125
5358 #define SSL_R_CERT_CB_ERROR 126
5359 #define SSL_R_CERT_LENGTH_MISMATCH 127
5360 #define SSL_R_CHANNEL_ID_NOT_P256 128
5361 #define SSL_R_CHANNEL_ID_SIGNATURE_INVALID 129
5362 #define SSL_R_CIPHER_OR_HASH_UNAVAILABLE 130
5363 #define SSL_R_CLIENTHELLO_PARSE_FAILED 131
5364 #define SSL_R_CLIENTHELLO_TLSEXT 132
5365 #define SSL_R_CONNECTION_REJECTED 133
5366 #define SSL_R_CONNECTION_TYPE_NOT_SET 134
5367 #define SSL_R_CUSTOM_EXTENSION_ERROR 135
5368 #define SSL_R_DATA_LENGTH_TOO_LONG 136
5369 #define SSL_R_DECODE_ERROR 137
5370 #define SSL_R_DECRYPTION_FAILED 138
5371 #define SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC 139
5372 #define SSL_R_DH_PUBLIC_VALUE_LENGTH_IS_WRONG 140
5373 #define SSL_R_DH_P_TOO_LONG 141
5374 #define SSL_R_DIGEST_CHECK_FAILED 142
5375 #define SSL_R_DTLS_MESSAGE_TOO_BIG 143
5376 #define SSL_R_ECC_CERT_NOT_FOR_SIGNING 144
5377 #define SSL_R_EMS_STATE_INCONSISTENT 145
5378 #define SSL_R_ENCRYPTED_LENGTH_TOO_LONG 146
5379 #define SSL_R_ERROR_ADDING_EXTENSION 147
5380 #define SSL_R_ERROR_IN_RECEIVED_CIPHER_LIST 148
5381 #define SSL_R_ERROR_PARSING_EXTENSION 149
5382 #define SSL_R_EXCESSIVE_MESSAGE_SIZE 150
5383 #define SSL_R_EXTRA_DATA_IN_MESSAGE 151
5384 #define SSL_R_FRAGMENT_MISMATCH 152
5385 #define SSL_R_GOT_NEXT_PROTO_WITHOUT_EXTENSION 153
5386 #define SSL_R_HANDSHAKE_FAILURE_ON_CLIENT_HELLO 154
5387 #define SSL_R_HTTPS_PROXY_REQUEST 155
5388 #define SSL_R_HTTP_REQUEST 156
5389 #define SSL_R_INAPPROPRIATE_FALLBACK 157
5390 #define SSL_R_INVALID_COMMAND 158
5391 #define SSL_R_INVALID_MESSAGE 159
5392 #define SSL_R_INVALID_SSL_SESSION 160
5393 #define SSL_R_INVALID_TICKET_KEYS_LENGTH 161
5394 #define SSL_R_LENGTH_MISMATCH 162
5395 #define SSL_R_MISSING_EXTENSION 164
5396 #define SSL_R_MISSING_RSA_CERTIFICATE 165
5397 #define SSL_R_MISSING_TMP_DH_KEY 166
5398 #define SSL_R_MISSING_TMP_ECDH_KEY 167
5399 #define SSL_R_MIXED_SPECIAL_OPERATOR_WITH_GROUPS 168
5400 #define SSL_R_MTU_TOO_SMALL 169
5401 #define SSL_R_NEGOTIATED_BOTH_NPN_AND_ALPN 170
5402 #define SSL_R_NESTED_GROUP 171
5403 #define SSL_R_NO_CERTIFICATES_RETURNED 172
5404 #define SSL_R_NO_CERTIFICATE_ASSIGNED 173
5405 #define SSL_R_NO_CERTIFICATE_SET 174
5406 #define SSL_R_NO_CIPHERS_AVAILABLE 175
5407 #define SSL_R_NO_CIPHERS_PASSED 176
5408 #define SSL_R_NO_CIPHER_MATCH 177
5409 #define SSL_R_NO_COMPRESSION_SPECIFIED 178
5410 #define SSL_R_NO_METHOD_SPECIFIED 179
5411 #define SSL_R_NO_P256_SUPPORT 180
5412 #define SSL_R_NO_PRIVATE_KEY_ASSIGNED 181
5413 #define SSL_R_NO_RENEGOTIATION 182
5414 #define SSL_R_NO_REQUIRED_DIGEST 183
5415 #define SSL_R_NO_SHARED_CIPHER 184
5416 #define SSL_R_NULL_SSL_CTX 185
5417 #define SSL_R_NULL_SSL_METHOD_PASSED 186
5418 #define SSL_R_OLD_SESSION_CIPHER_NOT_RETURNED 187
5419 #define SSL_R_OLD_SESSION_VERSION_NOT_RETURNED 188
5420 #define SSL_R_OUTPUT_ALIASES_INPUT 189
5421 #define SSL_R_PARSE_TLSEXT 190
5422 #define SSL_R_PATH_TOO_LONG 191
5423 #define SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE 192
5424 #define SSL_R_PEER_ERROR_UNSUPPORTED_CERTIFICATE_TYPE 193
5425 #define SSL_R_PROTOCOL_IS_SHUTDOWN 194
5426 #define SSL_R_PSK_IDENTITY_NOT_FOUND 195
5427 #define SSL_R_PSK_NO_CLIENT_CB 196
5428 #define SSL_R_PSK_NO_SERVER_CB 197
5429 #define SSL_R_READ_TIMEOUT_EXPIRED 198
5430 #define SSL_R_RECORD_LENGTH_MISMATCH 199
5431 #define SSL_R_RECORD_TOO_LARGE 200
5432 #define SSL_R_RENEGOTIATION_ENCODING_ERR 201
5433 #define SSL_R_RENEGOTIATION_MISMATCH 202
5434 #define SSL_R_REQUIRED_CIPHER_MISSING 203
5435 #define SSL_R_RESUMED_EMS_SESSION_WITHOUT_EMS_EXTENSION 204
5436 #define SSL_R_RESUMED_NON_EMS_SESSION_WITH_EMS_EXTENSION 205
5437 #define SSL_R_SCSV_RECEIVED_WHEN_RENEGOTIATING 206
5438 #define SSL_R_SERVERHELLO_TLSEXT 207
5439 #define SSL_R_SESSION_ID_CONTEXT_UNINITIALIZED 208
5440 #define SSL_R_SESSION_MAY_NOT_BE_CREATED 209
5441 #define SSL_R_SIGNATURE_ALGORITHMS_EXTENSION_SENT_BY_SERVER 210
5442 #define SSL_R_SRTP_COULD_NOT_ALLOCATE_PROFILES 211
5443 #define SSL_R_SRTP_UNKNOWN_PROTECTION_PROFILE 212
5444 #define SSL_R_SSL3_EXT_INVALID_SERVERNAME 213
5445 #define SSL_R_SSL_CTX_HAS_NO_DEFAULT_SSL_VERSION 214
5446 #define SSL_R_SSL_HANDSHAKE_FAILURE 215
5447 #define SSL_R_SSL_SESSION_ID_CONTEXT_TOO_LONG 216
5448 #define SSL_R_TLS_PEER_DID_NOT_RESPOND_WITH_CERTIFICATE_LIST 217
5449 #define SSL_R_TLS_RSA_ENCRYPTED_VALUE_LENGTH_IS_WRONG 218
5450 #define SSL_R_TOO_MANY_EMPTY_FRAGMENTS 219
5451 #define SSL_R_TOO_MANY_WARNING_ALERTS 220
5452 #define SSL_R_UNABLE_TO_FIND_ECDH_PARAMETERS 221
5453 #define SSL_R_UNEXPECTED_EXTENSION 222
5454 #define SSL_R_UNEXPECTED_MESSAGE 223
5455 #define SSL_R_UNEXPECTED_OPERATOR_IN_GROUP 224
5456 #define SSL_R_UNEXPECTED_RECORD 225
5457 #define SSL_R_UNINITIALIZED 226
5458 #define SSL_R_UNKNOWN_ALERT_TYPE 227
5459 #define SSL_R_UNKNOWN_CERTIFICATE_TYPE 228
5460 #define SSL_R_UNKNOWN_CIPHER_RETURNED 229
5461 #define SSL_R_UNKNOWN_CIPHER_TYPE 230
5462 #define SSL_R_UNKNOWN_DIGEST 231
5463 #define SSL_R_UNKNOWN_KEY_EXCHANGE_TYPE 232
5464 #define SSL_R_UNKNOWN_PROTOCOL 233
5465 #define SSL_R_UNKNOWN_SSL_VERSION 234
5466 #define SSL_R_UNKNOWN_STATE 235
5467 #define SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED 236
5468 #define SSL_R_UNSUPPORTED_CIPHER 237
5469 #define SSL_R_UNSUPPORTED_COMPRESSION_ALGORITHM 238
5470 #define SSL_R_UNSUPPORTED_ELLIPTIC_CURVE 239
5471 #define SSL_R_UNSUPPORTED_PROTOCOL 240
5472 #define SSL_R_WRONG_CERTIFICATE_TYPE 241
5473 #define SSL_R_WRONG_CIPHER_RETURNED 242
5474 #define SSL_R_WRONG_CURVE 243
5475 #define SSL_R_WRONG_MESSAGE_TYPE 244
5476 #define SSL_R_WRONG_SIGNATURE_TYPE 245
5477 #define SSL_R_WRONG_SSL_VERSION 246
5478 #define SSL_R_WRONG_VERSION_NUMBER 247
5479 #define SSL_R_X509_LIB 248
5480 #define SSL_R_X509_VERIFICATION_SETUP_PROBLEMS 249
5481 #define SSL_R_SHUTDOWN_WHILE_IN_INIT 250
5482 #define SSL_R_INVALID_OUTER_RECORD_TYPE 251
5483 #define SSL_R_UNSUPPORTED_PROTOCOL_FOR_CUSTOM_KEY 252
5484 #define SSL_R_NO_COMMON_SIGNATURE_ALGORITHMS 253
5485 #define SSL_R_DOWNGRADE_DETECTED 254
5486 #define SSL_R_EXCESS_HANDSHAKE_DATA 255
5487 #define SSL_R_INVALID_COMPRESSION_LIST 256
5488 #define SSL_R_DUPLICATE_EXTENSION 257
5489 #define SSL_R_MISSING_KEY_SHARE 258
5490 #define SSL_R_INVALID_ALPN_PROTOCOL 259
5491 #define SSL_R_TOO_MANY_KEY_UPDATES 260
5492 #define SSL_R_BLOCK_CIPHER_PAD_IS_WRONG 261
5493 #define SSL_R_NO_CIPHERS_SPECIFIED 262
5494 #define SSL_R_RENEGOTIATION_EMS_MISMATCH 263
5495 #define SSL_R_DUPLICATE_KEY_SHARE 264
5496 #define SSL_R_NO_GROUPS_SPECIFIED 265
5497 #define SSL_R_NO_SHARED_GROUP 266
5498 #define SSL_R_PRE_SHARED_KEY_MUST_BE_LAST 267
5499 #define SSL_R_OLD_SESSION_PRF_HASH_MISMATCH 268
5500 #define SSL_R_INVALID_SCT_LIST 269
5501 #define SSL_R_TOO_MUCH_SKIPPED_EARLY_DATA 270
5502 #define SSL_R_PSK_IDENTITY_BINDER_COUNT_MISMATCH 271
5503 #define SSL_R_CANNOT_PARSE_LEAF_CERT 272
5504 #define SSL_R_SERVER_CERT_CHANGED 273
5505 #define SSL_R_CERTIFICATE_AND_PRIVATE_KEY_MISMATCH 274
5506 #define SSL_R_CANNOT_HAVE_BOTH_PRIVKEY_AND_METHOD 275
5507 #define SSL_R_TICKET_ENCRYPTION_FAILED 276
5508 #define SSL_R_ALPN_MISMATCH_ON_EARLY_DATA 277
5509 #define SSL_R_WRONG_VERSION_ON_EARLY_DATA 278
5510 #define SSL_R_UNEXPECTED_EXTENSION_ON_EARLY_DATA 279
5511 #define SSL_R_NO_SUPPORTED_VERSIONS_ENABLED 280
5512 #define SSL_R_APPLICATION_DATA_INSTEAD_OF_HANDSHAKE 281
5513 #define SSL_R_EMPTY_HELLO_RETRY_REQUEST 282
5514 #define SSL_R_EARLY_DATA_NOT_IN_USE 283
5515 #define SSL_R_HANDSHAKE_NOT_COMPLETE 284
5516 #define SSL_R_NEGOTIATED_TB_WITHOUT_EMS_OR_RI 285
5517 #define SSL_R_SERVER_ECHOED_INVALID_SESSION_ID 286
5518 #define SSL_R_PRIVATE_KEY_OPERATION_FAILED 287
5519 #define SSL_R_SECOND_SERVERHELLO_VERSION_MISMATCH 288
5520 #define SSL_R_OCSP_CB_ERROR 289
5521 #define SSL_R_SSL_SESSION_ID_TOO_LONG 290
5522 #define SSL_R_APPLICATION_DATA_ON_SHUTDOWN 291
5523 #define SSL_R_CERT_DECOMPRESSION_FAILED 292
5524 #define SSL_R_UNCOMPRESSED_CERT_TOO_LARGE 293
5525 #define SSL_R_UNKNOWN_CERT_COMPRESSION_ALG 294
5526 #define SSL_R_INVALID_SIGNATURE_ALGORITHM 295
5527 #define SSL_R_DUPLICATE_SIGNATURE_ALGORITHM 296
5528 #define SSL_R_TLS13_DOWNGRADE 297
5529 #define SSL_R_QUIC_INTERNAL_ERROR 298
5530 #define SSL_R_WRONG_ENCRYPTION_LEVEL_RECEIVED 299
5531 #define SSL_R_TOO_MUCH_READ_EARLY_DATA 300
5532 #define SSL_R_INVALID_DELEGATED_CREDENTIAL 301
5533 #define SSL_R_KEY_USAGE_BIT_INCORRECT 302
5534 #define SSL_R_INCONSISTENT_CLIENT_HELLO 303
5535 #define SSL_R_CIPHER_MISMATCH_ON_EARLY_DATA 304
5536 #define SSL_R_QUIC_TRANSPORT_PARAMETERS_MISCONFIGURED 305
5537 #define SSL_R_UNEXPECTED_COMPATIBILITY_MODE 306
5538 #define SSL_R_NO_APPLICATION_PROTOCOL 307
5539 #define SSL_R_NEGOTIATED_ALPS_WITHOUT_ALPN 308
5540 #define SSL_R_ALPS_MISMATCH_ON_EARLY_DATA 309
5541 #define SSL_R_ECH_SERVER_CONFIG_AND_PRIVATE_KEY_MISMATCH 310
5542 #define SSL_R_ECH_SERVER_CONFIG_UNSUPPORTED_EXTENSION 311
5543 #define SSL_R_UNSUPPORTED_ECH_SERVER_CONFIG 312
5544 #define SSL_R_ECH_SERVER_WOULD_HAVE_NO_RETRY_CONFIGS 313
5545 #define SSL_R_INVALID_CLIENT_HELLO_INNER 314
5546 #define SSL_R_INVALID_ALPN_PROTOCOL_LIST 315
5547 #define SSL_R_COULD_NOT_PARSE_HINTS 316
5548 #define SSL_R_INVALID_ECH_PUBLIC_NAME 317
5549 #define SSL_R_INVALID_ECH_CONFIG_LIST 318
5550 #define SSL_R_ECH_REJECTED 319
5551 #define SSL_R_OUTER_EXTENSION_NOT_FOUND 320
5552 #define SSL_R_INCONSISTENT_ECH_NEGOTIATION 321
5553 #define SSL_R_SSLV3_ALERT_CLOSE_NOTIFY 1000
5554 #define SSL_R_SSLV3_ALERT_UNEXPECTED_MESSAGE 1010
5555 #define SSL_R_SSLV3_ALERT_BAD_RECORD_MAC 1020
5556 #define SSL_R_TLSV1_ALERT_DECRYPTION_FAILED 1021
5557 #define SSL_R_TLSV1_ALERT_RECORD_OVERFLOW 1022
5558 #define SSL_R_SSLV3_ALERT_DECOMPRESSION_FAILURE 1030
5559 #define SSL_R_SSLV3_ALERT_HANDSHAKE_FAILURE 1040
5560 #define SSL_R_SSLV3_ALERT_NO_CERTIFICATE 1041
5561 #define SSL_R_SSLV3_ALERT_BAD_CERTIFICATE 1042
5562 #define SSL_R_SSLV3_ALERT_UNSUPPORTED_CERTIFICATE 1043
5563 #define SSL_R_SSLV3_ALERT_CERTIFICATE_REVOKED 1044
5564 #define SSL_R_SSLV3_ALERT_CERTIFICATE_EXPIRED 1045
5565 #define SSL_R_SSLV3_ALERT_CERTIFICATE_UNKNOWN 1046
5566 #define SSL_R_SSLV3_ALERT_ILLEGAL_PARAMETER 1047
5567 #define SSL_R_TLSV1_ALERT_UNKNOWN_CA 1048
5568 #define SSL_R_TLSV1_ALERT_ACCESS_DENIED 1049
5569 #define SSL_R_TLSV1_ALERT_DECODE_ERROR 1050
5570 #define SSL_R_TLSV1_ALERT_DECRYPT_ERROR 1051
5571 #define SSL_R_TLSV1_ALERT_EXPORT_RESTRICTION 1060
5572 #define SSL_R_TLSV1_ALERT_PROTOCOL_VERSION 1070
5573 #define SSL_R_TLSV1_ALERT_INSUFFICIENT_SECURITY 1071
5574 #define SSL_R_TLSV1_ALERT_INTERNAL_ERROR 1080
5575 #define SSL_R_TLSV1_ALERT_INAPPROPRIATE_FALLBACK 1086
5576 #define SSL_R_TLSV1_ALERT_USER_CANCELLED 1090
5577 #define SSL_R_TLSV1_ALERT_NO_RENEGOTIATION 1100
5578 #define SSL_R_TLSV1_ALERT_UNSUPPORTED_EXTENSION 1110
5579 #define SSL_R_TLSV1_ALERT_CERTIFICATE_UNOBTAINABLE 1111
5580 #define SSL_R_TLSV1_ALERT_UNRECOGNIZED_NAME 1112
5581 #define SSL_R_TLSV1_ALERT_BAD_CERTIFICATE_STATUS_RESPONSE 1113
5582 #define SSL_R_TLSV1_ALERT_BAD_CERTIFICATE_HASH_VALUE 1114
5583 #define SSL_R_TLSV1_ALERT_UNKNOWN_PSK_IDENTITY 1115
5584 #define SSL_R_TLSV1_ALERT_CERTIFICATE_REQUIRED 1116
5585 #define SSL_R_TLSV1_ALERT_NO_APPLICATION_PROTOCOL 1120
5586 #define SSL_R_TLSV1_ALERT_ECH_REQUIRED 1121
5587 
5588 #endif  // OPENSSL_HEADER_SSL_H
5589