xref: /freebsd/crypto/openssl/ssl/ssl_sess.c (revision b1f9167f94059fd55c630891d359bcff987bd7eb)
1 /* ssl/ssl_sess.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3  * All rights reserved.
4  *
5  * This package is an SSL implementation written
6  * by Eric Young (eay@cryptsoft.com).
7  * The implementation was written so as to conform with Netscapes SSL.
8  *
9  * This library is free for commercial and non-commercial use as long as
10  * the following conditions are aheared to.  The following conditions
11  * apply to all code found in this distribution, be it the RC4, RSA,
12  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
13  * included with this distribution is covered by the same copyright terms
14  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15  *
16  * Copyright remains Eric Young's, and as such any Copyright notices in
17  * the code are not to be removed.
18  * If this package is used in a product, Eric Young should be given attribution
19  * as the author of the parts of the library used.
20  * This can be in the form of a textual message at program startup or
21  * in documentation (online or textual) provided with the package.
22  *
23  * Redistribution and use in source and binary forms, with or without
24  * modification, are permitted provided that the following conditions
25  * are met:
26  * 1. Redistributions of source code must retain the copyright
27  *    notice, this list of conditions and the following disclaimer.
28  * 2. Redistributions in binary form must reproduce the above copyright
29  *    notice, this list of conditions and the following disclaimer in the
30  *    documentation and/or other materials provided with the distribution.
31  * 3. All advertising materials mentioning features or use of this software
32  *    must display the following acknowledgement:
33  *    "This product includes cryptographic software written by
34  *     Eric Young (eay@cryptsoft.com)"
35  *    The word 'cryptographic' can be left out if the rouines from the library
36  *    being used are not cryptographic related :-).
37  * 4. If you include any Windows specific code (or a derivative thereof) from
38  *    the apps directory (application code) you must include an acknowledgement:
39  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40  *
41  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51  * SUCH DAMAGE.
52  *
53  * The licence and distribution terms for any publically available version or
54  * derivative of this code cannot be changed.  i.e. this code cannot simply be
55  * copied and put under another distribution licence
56  * [including the GNU Public Licence.]
57  */
58 /* ====================================================================
59  * Copyright (c) 1998-2006 The OpenSSL Project.  All rights reserved.
60  *
61  * Redistribution and use in source and binary forms, with or without
62  * modification, are permitted provided that the following conditions
63  * are met:
64  *
65  * 1. Redistributions of source code must retain the above copyright
66  *    notice, this list of conditions and the following disclaimer.
67  *
68  * 2. Redistributions in binary form must reproduce the above copyright
69  *    notice, this list of conditions and the following disclaimer in
70  *    the documentation and/or other materials provided with the
71  *    distribution.
72  *
73  * 3. All advertising materials mentioning features or use of this
74  *    software must display the following acknowledgment:
75  *    "This product includes software developed by the OpenSSL Project
76  *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
77  *
78  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
79  *    endorse or promote products derived from this software without
80  *    prior written permission. For written permission, please contact
81  *    openssl-core@openssl.org.
82  *
83  * 5. Products derived from this software may not be called "OpenSSL"
84  *    nor may "OpenSSL" appear in their names without prior written
85  *    permission of the OpenSSL Project.
86  *
87  * 6. Redistributions of any form whatsoever must retain the following
88  *    acknowledgment:
89  *    "This product includes software developed by the OpenSSL Project
90  *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
91  *
92  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
93  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
94  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
95  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
96  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
97  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
98  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
99  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
100  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
101  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
102  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
103  * OF THE POSSIBILITY OF SUCH DAMAGE.
104  * ====================================================================
105  *
106  * This product includes cryptographic software written by Eric Young
107  * (eay@cryptsoft.com).  This product includes software written by Tim
108  * Hudson (tjh@cryptsoft.com).
109  *
110  */
111 /* ====================================================================
112  * Copyright 2005 Nokia. All rights reserved.
113  *
114  * The portions of the attached software ("Contribution") is developed by
115  * Nokia Corporation and is licensed pursuant to the OpenSSL open source
116  * license.
117  *
118  * The Contribution, originally written by Mika Kousa and Pasi Eronen of
119  * Nokia Corporation, consists of the "PSK" (Pre-Shared Key) ciphersuites
120  * support (see RFC 4279) to OpenSSL.
121  *
122  * No patent licenses or other rights except those expressly stated in
123  * the OpenSSL open source license shall be deemed granted or received
124  * expressly, by implication, estoppel, or otherwise.
125  *
126  * No assurances are provided by Nokia that the Contribution does not
127  * infringe the patent or other intellectual property rights of any third
128  * party or that the license provides you with all the necessary rights
129  * to make use of the Contribution.
130  *
131  * THE SOFTWARE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. IN
132  * ADDITION TO THE DISCLAIMERS INCLUDED IN THE LICENSE, NOKIA
133  * SPECIFICALLY DISCLAIMS ANY LIABILITY FOR CLAIMS BROUGHT BY YOU OR ANY
134  * OTHER ENTITY BASED ON INFRINGEMENT OF INTELLECTUAL PROPERTY RIGHTS OR
135  * OTHERWISE.
136  */
137 
138 #include <stdio.h>
139 #include <openssl/lhash.h>
140 #include <openssl/rand.h>
141 #ifndef OPENSSL_NO_ENGINE
142 #include <openssl/engine.h>
143 #endif
144 #include "ssl_locl.h"
145 
146 static void SSL_SESSION_list_remove(SSL_CTX *ctx, SSL_SESSION *s);
147 static void SSL_SESSION_list_add(SSL_CTX *ctx,SSL_SESSION *s);
148 static int remove_session_lock(SSL_CTX *ctx, SSL_SESSION *c, int lck);
149 
150 SSL_SESSION *SSL_get_session(const SSL *ssl)
151 /* aka SSL_get0_session; gets 0 objects, just returns a copy of the pointer */
152 	{
153 	return(ssl->session);
154 	}
155 
156 SSL_SESSION *SSL_get1_session(SSL *ssl)
157 /* variant of SSL_get_session: caller really gets something */
158 	{
159 	SSL_SESSION *sess;
160 	/* Need to lock this all up rather than just use CRYPTO_add so that
161 	 * somebody doesn't free ssl->session between when we check it's
162 	 * non-null and when we up the reference count. */
163 	CRYPTO_w_lock(CRYPTO_LOCK_SSL_SESSION);
164 	sess = ssl->session;
165 	if(sess)
166 		sess->references++;
167 	CRYPTO_w_unlock(CRYPTO_LOCK_SSL_SESSION);
168 	return(sess);
169 	}
170 
171 int SSL_SESSION_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,
172 	     CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func)
173 	{
174 	return CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_SSL_SESSION, argl, argp,
175 			new_func, dup_func, free_func);
176 	}
177 
178 int SSL_SESSION_set_ex_data(SSL_SESSION *s, int idx, void *arg)
179 	{
180 	return(CRYPTO_set_ex_data(&s->ex_data,idx,arg));
181 	}
182 
183 void *SSL_SESSION_get_ex_data(const SSL_SESSION *s, int idx)
184 	{
185 	return(CRYPTO_get_ex_data(&s->ex_data,idx));
186 	}
187 
188 SSL_SESSION *SSL_SESSION_new(void)
189 	{
190 	SSL_SESSION *ss;
191 
192 	ss=(SSL_SESSION *)OPENSSL_malloc(sizeof(SSL_SESSION));
193 	if (ss == NULL)
194 		{
195 		SSLerr(SSL_F_SSL_SESSION_NEW,ERR_R_MALLOC_FAILURE);
196 		return(0);
197 		}
198 	memset(ss,0,sizeof(SSL_SESSION));
199 
200 	ss->verify_result = 1; /* avoid 0 (= X509_V_OK) just in case */
201 	ss->references=1;
202 	ss->timeout=60*5+4; /* 5 minute timeout by default */
203 	ss->time=(unsigned long)time(NULL);
204 	ss->prev=NULL;
205 	ss->next=NULL;
206 	ss->compress_meth=0;
207 #ifndef OPENSSL_NO_TLSEXT
208 	ss->tlsext_hostname = NULL;
209 #ifndef OPENSSL_NO_EC
210 	ss->tlsext_ecpointformatlist_length = 0;
211 	ss->tlsext_ecpointformatlist = NULL;
212 	ss->tlsext_ellipticcurvelist_length = 0;
213 	ss->tlsext_ellipticcurvelist = NULL;
214 #endif
215 #endif
216 	CRYPTO_new_ex_data(CRYPTO_EX_INDEX_SSL_SESSION, ss, &ss->ex_data);
217 #ifndef OPENSSL_NO_PSK
218 	ss->psk_identity_hint=NULL;
219 	ss->psk_identity=NULL;
220 #endif
221 #ifndef OPENSSL_NO_SRP
222 	ss->srp_username=NULL;
223 #endif
224 	return(ss);
225 	}
226 
227 const unsigned char *SSL_SESSION_get_id(const SSL_SESSION *s, unsigned int *len)
228 	{
229 	if(len)
230 		*len = s->session_id_length;
231 	return s->session_id;
232 	}
233 
234 unsigned int SSL_SESSION_get_compress_id(const SSL_SESSION *s)
235 	{
236 	return s->compress_meth;
237 	}
238 
239 /* Even with SSLv2, we have 16 bytes (128 bits) of session ID space. SSLv3/TLSv1
240  * has 32 bytes (256 bits). As such, filling the ID with random gunk repeatedly
241  * until we have no conflict is going to complete in one iteration pretty much
242  * "most" of the time (btw: understatement). So, if it takes us 10 iterations
243  * and we still can't avoid a conflict - well that's a reasonable point to call
244  * it quits. Either the RAND code is broken or someone is trying to open roughly
245  * very close to 2^128 (or 2^256) SSL sessions to our server. How you might
246  * store that many sessions is perhaps a more interesting question ... */
247 
248 #define MAX_SESS_ID_ATTEMPTS 10
249 static int def_generate_session_id(const SSL *ssl, unsigned char *id,
250 				unsigned int *id_len)
251 {
252 	unsigned int retry = 0;
253 	do
254 		if (RAND_pseudo_bytes(id, *id_len) <= 0)
255 			return 0;
256 	while(SSL_has_matching_session_id(ssl, id, *id_len) &&
257 		(++retry < MAX_SESS_ID_ATTEMPTS));
258 	if(retry < MAX_SESS_ID_ATTEMPTS)
259 		return 1;
260 	/* else - woops a session_id match */
261 	/* XXX We should also check the external cache --
262 	 * but the probability of a collision is negligible, and
263 	 * we could not prevent the concurrent creation of sessions
264 	 * with identical IDs since we currently don't have means
265 	 * to atomically check whether a session ID already exists
266 	 * and make a reservation for it if it does not
267 	 * (this problem applies to the internal cache as well).
268 	 */
269 	return 0;
270 }
271 
272 int ssl_get_new_session(SSL *s, int session)
273 	{
274 	/* This gets used by clients and servers. */
275 
276 	unsigned int tmp;
277 	SSL_SESSION *ss=NULL;
278 	GEN_SESSION_CB cb = def_generate_session_id;
279 
280 	if ((ss=SSL_SESSION_new()) == NULL) return(0);
281 
282 	/* If the context has a default timeout, use it */
283 	if (s->session_ctx->session_timeout == 0)
284 		ss->timeout=SSL_get_default_timeout(s);
285 	else
286 		ss->timeout=s->session_ctx->session_timeout;
287 
288 	if (s->session != NULL)
289 		{
290 		SSL_SESSION_free(s->session);
291 		s->session=NULL;
292 		}
293 
294 	if (session)
295 		{
296 		if (s->version == SSL2_VERSION)
297 			{
298 			ss->ssl_version=SSL2_VERSION;
299 			ss->session_id_length=SSL2_SSL_SESSION_ID_LENGTH;
300 			}
301 		else if (s->version == SSL3_VERSION)
302 			{
303 			ss->ssl_version=SSL3_VERSION;
304 			ss->session_id_length=SSL3_SSL_SESSION_ID_LENGTH;
305 			}
306 		else if (s->version == TLS1_VERSION)
307 			{
308 			ss->ssl_version=TLS1_VERSION;
309 			ss->session_id_length=SSL3_SSL_SESSION_ID_LENGTH;
310 			}
311 		else if (s->version == TLS1_1_VERSION)
312 			{
313 			ss->ssl_version=TLS1_1_VERSION;
314 			ss->session_id_length=SSL3_SSL_SESSION_ID_LENGTH;
315 			}
316 		else if (s->version == TLS1_2_VERSION)
317 			{
318 			ss->ssl_version=TLS1_2_VERSION;
319 			ss->session_id_length=SSL3_SSL_SESSION_ID_LENGTH;
320 			}
321 		else if (s->version == DTLS1_BAD_VER)
322 			{
323 			ss->ssl_version=DTLS1_BAD_VER;
324 			ss->session_id_length=SSL3_SSL_SESSION_ID_LENGTH;
325 			}
326 		else if (s->version == DTLS1_VERSION)
327 			{
328 			ss->ssl_version=DTLS1_VERSION;
329 			ss->session_id_length=SSL3_SSL_SESSION_ID_LENGTH;
330 			}
331 		else
332 			{
333 			SSLerr(SSL_F_SSL_GET_NEW_SESSION,SSL_R_UNSUPPORTED_SSL_VERSION);
334 			SSL_SESSION_free(ss);
335 			return(0);
336 			}
337 #ifndef OPENSSL_NO_TLSEXT
338 		/* If RFC4507 ticket use empty session ID */
339 		if (s->tlsext_ticket_expected)
340 			{
341 			ss->session_id_length = 0;
342 			goto sess_id_done;
343 			}
344 #endif
345 		/* Choose which callback will set the session ID */
346 		CRYPTO_r_lock(CRYPTO_LOCK_SSL_CTX);
347 		if(s->generate_session_id)
348 			cb = s->generate_session_id;
349 		else if(s->session_ctx->generate_session_id)
350 			cb = s->session_ctx->generate_session_id;
351 		CRYPTO_r_unlock(CRYPTO_LOCK_SSL_CTX);
352 		/* Choose a session ID */
353 		tmp = ss->session_id_length;
354 		if(!cb(s, ss->session_id, &tmp))
355 			{
356 			/* The callback failed */
357 			SSLerr(SSL_F_SSL_GET_NEW_SESSION,
358 				SSL_R_SSL_SESSION_ID_CALLBACK_FAILED);
359 			SSL_SESSION_free(ss);
360 			return(0);
361 			}
362 		/* Don't allow the callback to set the session length to zero.
363 		 * nor set it higher than it was. */
364 		if(!tmp || (tmp > ss->session_id_length))
365 			{
366 			/* The callback set an illegal length */
367 			SSLerr(SSL_F_SSL_GET_NEW_SESSION,
368 				SSL_R_SSL_SESSION_ID_HAS_BAD_LENGTH);
369 			SSL_SESSION_free(ss);
370 			return(0);
371 			}
372 		/* If the session length was shrunk and we're SSLv2, pad it */
373 		if((tmp < ss->session_id_length) && (s->version == SSL2_VERSION))
374 			memset(ss->session_id + tmp, 0, ss->session_id_length - tmp);
375 		else
376 			ss->session_id_length = tmp;
377 		/* Finally, check for a conflict */
378 		if(SSL_has_matching_session_id(s, ss->session_id,
379 						ss->session_id_length))
380 			{
381 			SSLerr(SSL_F_SSL_GET_NEW_SESSION,
382 				SSL_R_SSL_SESSION_ID_CONFLICT);
383 			SSL_SESSION_free(ss);
384 			return(0);
385 			}
386 #ifndef OPENSSL_NO_TLSEXT
387 		sess_id_done:
388 		if (s->tlsext_hostname) {
389 			ss->tlsext_hostname = BUF_strdup(s->tlsext_hostname);
390 			if (ss->tlsext_hostname == NULL) {
391 				SSLerr(SSL_F_SSL_GET_NEW_SESSION, ERR_R_INTERNAL_ERROR);
392 				SSL_SESSION_free(ss);
393 				return 0;
394 				}
395 			}
396 #ifndef OPENSSL_NO_EC
397 		if (s->tlsext_ecpointformatlist)
398 			{
399 			if (ss->tlsext_ecpointformatlist != NULL) OPENSSL_free(ss->tlsext_ecpointformatlist);
400 			if ((ss->tlsext_ecpointformatlist = OPENSSL_malloc(s->tlsext_ecpointformatlist_length)) == NULL)
401 				{
402 				SSLerr(SSL_F_SSL_GET_NEW_SESSION, ERR_R_MALLOC_FAILURE);
403 				SSL_SESSION_free(ss);
404 				return 0;
405 				}
406 			ss->tlsext_ecpointformatlist_length = s->tlsext_ecpointformatlist_length;
407 			memcpy(ss->tlsext_ecpointformatlist, s->tlsext_ecpointformatlist, s->tlsext_ecpointformatlist_length);
408 			}
409 		if (s->tlsext_ellipticcurvelist)
410 			{
411 			if (ss->tlsext_ellipticcurvelist != NULL) OPENSSL_free(ss->tlsext_ellipticcurvelist);
412 			if ((ss->tlsext_ellipticcurvelist = OPENSSL_malloc(s->tlsext_ellipticcurvelist_length)) == NULL)
413 				{
414 				SSLerr(SSL_F_SSL_GET_NEW_SESSION, ERR_R_MALLOC_FAILURE);
415 				SSL_SESSION_free(ss);
416 				return 0;
417 				}
418 			ss->tlsext_ellipticcurvelist_length = s->tlsext_ellipticcurvelist_length;
419 			memcpy(ss->tlsext_ellipticcurvelist, s->tlsext_ellipticcurvelist, s->tlsext_ellipticcurvelist_length);
420 			}
421 #endif
422 #endif
423 		}
424 	else
425 		{
426 		ss->session_id_length=0;
427 		}
428 
429 	if (s->sid_ctx_length > sizeof ss->sid_ctx)
430 		{
431 		SSLerr(SSL_F_SSL_GET_NEW_SESSION, ERR_R_INTERNAL_ERROR);
432 		SSL_SESSION_free(ss);
433 		return 0;
434 		}
435 	memcpy(ss->sid_ctx,s->sid_ctx,s->sid_ctx_length);
436 	ss->sid_ctx_length=s->sid_ctx_length;
437 	s->session=ss;
438 	ss->ssl_version=s->version;
439 	ss->verify_result = X509_V_OK;
440 
441 	return(1);
442 	}
443 
444 /* ssl_get_prev attempts to find an SSL_SESSION to be used to resume this
445  * connection. It is only called by servers.
446  *
447  *   session_id: points at the session ID in the ClientHello. This code will
448  *       read past the end of this in order to parse out the session ticket
449  *       extension, if any.
450  *   len: the length of the session ID.
451  *   limit: a pointer to the first byte after the ClientHello.
452  *
453  * Returns:
454  *   -1: error
455  *    0: a session may have been found.
456  *
457  * Side effects:
458  *   - If a session is found then s->session is pointed at it (after freeing an
459  *     existing session if need be) and s->verify_result is set from the session.
460  *   - Both for new and resumed sessions, s->tlsext_ticket_expected is set to 1
461  *     if the server should issue a new session ticket (to 0 otherwise).
462  */
463 int ssl_get_prev_session(SSL *s, unsigned char *session_id, int len,
464 			const unsigned char *limit)
465 	{
466 	/* This is used only by servers. */
467 
468 	SSL_SESSION *ret=NULL;
469 	int fatal = 0;
470 	int try_session_cache = 1;
471 #ifndef OPENSSL_NO_TLSEXT
472 	int r;
473 #endif
474 
475 	if (len > SSL_MAX_SSL_SESSION_ID_LENGTH)
476 		goto err;
477 
478 	if (len == 0)
479 		try_session_cache = 0;
480 
481 #ifndef OPENSSL_NO_TLSEXT
482 	r = tls1_process_ticket(s, session_id, len, limit, &ret); /* sets s->tlsext_ticket_expected */
483 	switch (r)
484 		{
485 	case -1: /* Error during processing */
486 		fatal = 1;
487 		goto err;
488 	case 0: /* No ticket found */
489 	case 1: /* Zero length ticket found */
490 		break; /* Ok to carry on processing session id. */
491 	case 2: /* Ticket found but not decrypted. */
492 	case 3: /* Ticket decrypted, *ret has been set. */
493 		try_session_cache = 0;
494 		break;
495 	default:
496 		abort();
497 		}
498 #endif
499 
500 	if (try_session_cache &&
501 	    ret == NULL &&
502 	    !(s->session_ctx->session_cache_mode & SSL_SESS_CACHE_NO_INTERNAL_LOOKUP))
503 		{
504 		SSL_SESSION data;
505 		data.ssl_version=s->version;
506 		data.session_id_length=len;
507 		if (len == 0)
508 			return 0;
509 		memcpy(data.session_id,session_id,len);
510 		CRYPTO_r_lock(CRYPTO_LOCK_SSL_CTX);
511 		ret=lh_SSL_SESSION_retrieve(s->session_ctx->sessions,&data);
512 		if (ret != NULL)
513 			{
514 			/* don't allow other threads to steal it: */
515 			CRYPTO_add(&ret->references,1,CRYPTO_LOCK_SSL_SESSION);
516 			}
517 		CRYPTO_r_unlock(CRYPTO_LOCK_SSL_CTX);
518 		if (ret == NULL)
519 			s->session_ctx->stats.sess_miss++;
520 		}
521 
522 	if (try_session_cache &&
523 	    ret == NULL &&
524 	    s->session_ctx->get_session_cb != NULL)
525 		{
526 		int copy=1;
527 
528 		if ((ret=s->session_ctx->get_session_cb(s,session_id,len,&copy)))
529 			{
530 			s->session_ctx->stats.sess_cb_hit++;
531 
532 			/* Increment reference count now if the session callback
533 			 * asks us to do so (note that if the session structures
534 			 * returned by the callback are shared between threads,
535 			 * it must handle the reference count itself [i.e. copy == 0],
536 			 * or things won't be thread-safe). */
537 			if (copy)
538 				CRYPTO_add(&ret->references,1,CRYPTO_LOCK_SSL_SESSION);
539 
540 			/* Add the externally cached session to the internal
541 			 * cache as well if and only if we are supposed to. */
542 			if(!(s->session_ctx->session_cache_mode & SSL_SESS_CACHE_NO_INTERNAL_STORE))
543 				/* The following should not return 1, otherwise,
544 				 * things are very strange */
545 				SSL_CTX_add_session(s->session_ctx,ret);
546 			}
547 		}
548 
549 	if (ret == NULL)
550 		goto err;
551 
552 	/* Now ret is non-NULL and we own one of its reference counts. */
553 
554 	if (ret->sid_ctx_length != s->sid_ctx_length
555 	    || memcmp(ret->sid_ctx,s->sid_ctx,ret->sid_ctx_length))
556 		{
557 		/* We have the session requested by the client, but we don't
558 		 * want to use it in this context. */
559 		goto err; /* treat like cache miss */
560 		}
561 
562 	if((s->verify_mode & SSL_VERIFY_PEER) && s->sid_ctx_length == 0)
563 		{
564 		/* We can't be sure if this session is being used out of
565 		 * context, which is especially important for SSL_VERIFY_PEER.
566 		 * The application should have used SSL[_CTX]_set_session_id_context.
567 		 *
568 		 * For this error case, we generate an error instead of treating
569 		 * the event like a cache miss (otherwise it would be easy for
570 		 * applications to effectively disable the session cache by
571 		 * accident without anyone noticing).
572 		 */
573 
574 		SSLerr(SSL_F_SSL_GET_PREV_SESSION,SSL_R_SESSION_ID_CONTEXT_UNINITIALIZED);
575 		fatal = 1;
576 		goto err;
577 		}
578 
579 	if (ret->cipher == NULL)
580 		{
581 		unsigned char buf[5],*p;
582 		unsigned long l;
583 
584 		p=buf;
585 		l=ret->cipher_id;
586 		l2n(l,p);
587 		if ((ret->ssl_version>>8) >= SSL3_VERSION_MAJOR)
588 			ret->cipher=ssl_get_cipher_by_char(s,&(buf[2]));
589 		else
590 			ret->cipher=ssl_get_cipher_by_char(s,&(buf[1]));
591 		if (ret->cipher == NULL)
592 			goto err;
593 		}
594 
595 	if (ret->timeout < (long)(time(NULL) - ret->time)) /* timeout */
596 		{
597 		s->session_ctx->stats.sess_timeout++;
598 		if (try_session_cache)
599 			{
600 			/* session was from the cache, so remove it */
601 			SSL_CTX_remove_session(s->session_ctx,ret);
602 			}
603 		goto err;
604 		}
605 
606 	s->session_ctx->stats.sess_hit++;
607 
608 	if (s->session != NULL)
609 		SSL_SESSION_free(s->session);
610 	s->session=ret;
611 	s->verify_result = s->session->verify_result;
612 	return 1;
613 
614  err:
615 	if (ret != NULL)
616 		{
617 		SSL_SESSION_free(ret);
618 #ifndef OPENSSL_NO_TLSEXT
619 		if (!try_session_cache)
620 			{
621 			/* The session was from a ticket, so we should
622 			 * issue a ticket for the new session */
623 			s->tlsext_ticket_expected = 1;
624 			}
625 #endif
626 		}
627 	if (fatal)
628 		return -1;
629 	else
630 		return 0;
631 	}
632 
633 int SSL_CTX_add_session(SSL_CTX *ctx, SSL_SESSION *c)
634 	{
635 	int ret=0;
636 	SSL_SESSION *s;
637 
638 	/* add just 1 reference count for the SSL_CTX's session cache
639 	 * even though it has two ways of access: each session is in a
640 	 * doubly linked list and an lhash */
641 	CRYPTO_add(&c->references,1,CRYPTO_LOCK_SSL_SESSION);
642 	/* if session c is in already in cache, we take back the increment later */
643 
644 	CRYPTO_w_lock(CRYPTO_LOCK_SSL_CTX);
645 	s=lh_SSL_SESSION_insert(ctx->sessions,c);
646 
647 	/* s != NULL iff we already had a session with the given PID.
648 	 * In this case, s == c should hold (then we did not really modify
649 	 * ctx->sessions), or we're in trouble. */
650 	if (s != NULL && s != c)
651 		{
652 		/* We *are* in trouble ... */
653 		SSL_SESSION_list_remove(ctx,s);
654 		SSL_SESSION_free(s);
655 		/* ... so pretend the other session did not exist in cache
656 		 * (we cannot handle two SSL_SESSION structures with identical
657 		 * session ID in the same cache, which could happen e.g. when
658 		 * two threads concurrently obtain the same session from an external
659 		 * cache) */
660 		s = NULL;
661 		}
662 
663  	/* Put at the head of the queue unless it is already in the cache */
664 	if (s == NULL)
665 		SSL_SESSION_list_add(ctx,c);
666 
667 	if (s != NULL)
668 		{
669 		/* existing cache entry -- decrement previously incremented reference
670 		 * count because it already takes into account the cache */
671 
672 		SSL_SESSION_free(s); /* s == c */
673 		ret=0;
674 		}
675 	else
676 		{
677 		/* new cache entry -- remove old ones if cache has become too large */
678 
679 		ret=1;
680 
681 		if (SSL_CTX_sess_get_cache_size(ctx) > 0)
682 			{
683 			while (SSL_CTX_sess_number(ctx) >
684 				SSL_CTX_sess_get_cache_size(ctx))
685 				{
686 				if (!remove_session_lock(ctx,
687 					ctx->session_cache_tail, 0))
688 					break;
689 				else
690 					ctx->stats.sess_cache_full++;
691 				}
692 			}
693 		}
694 	CRYPTO_w_unlock(CRYPTO_LOCK_SSL_CTX);
695 	return(ret);
696 	}
697 
698 int SSL_CTX_remove_session(SSL_CTX *ctx, SSL_SESSION *c)
699 {
700 	return remove_session_lock(ctx, c, 1);
701 }
702 
703 static int remove_session_lock(SSL_CTX *ctx, SSL_SESSION *c, int lck)
704 	{
705 	SSL_SESSION *r;
706 	int ret=0;
707 
708 	if ((c != NULL) && (c->session_id_length != 0))
709 		{
710 		if(lck) CRYPTO_w_lock(CRYPTO_LOCK_SSL_CTX);
711 		if ((r = lh_SSL_SESSION_retrieve(ctx->sessions,c)) == c)
712 			{
713 			ret=1;
714 			r=lh_SSL_SESSION_delete(ctx->sessions,c);
715 			SSL_SESSION_list_remove(ctx,c);
716 			}
717 
718 		if(lck) CRYPTO_w_unlock(CRYPTO_LOCK_SSL_CTX);
719 
720 		if (ret)
721 			{
722 			r->not_resumable=1;
723 			if (ctx->remove_session_cb != NULL)
724 				ctx->remove_session_cb(ctx,r);
725 			SSL_SESSION_free(r);
726 			}
727 		}
728 	else
729 		ret=0;
730 	return(ret);
731 	}
732 
733 void SSL_SESSION_free(SSL_SESSION *ss)
734 	{
735 	int i;
736 
737 	if(ss == NULL)
738 	    return;
739 
740 	i=CRYPTO_add(&ss->references,-1,CRYPTO_LOCK_SSL_SESSION);
741 #ifdef REF_PRINT
742 	REF_PRINT("SSL_SESSION",ss);
743 #endif
744 	if (i > 0) return;
745 #ifdef REF_CHECK
746 	if (i < 0)
747 		{
748 		fprintf(stderr,"SSL_SESSION_free, bad reference count\n");
749 		abort(); /* ok */
750 		}
751 #endif
752 
753 	CRYPTO_free_ex_data(CRYPTO_EX_INDEX_SSL_SESSION, ss, &ss->ex_data);
754 
755 	OPENSSL_cleanse(ss->key_arg,sizeof ss->key_arg);
756 	OPENSSL_cleanse(ss->master_key,sizeof ss->master_key);
757 	OPENSSL_cleanse(ss->session_id,sizeof ss->session_id);
758 	if (ss->sess_cert != NULL) ssl_sess_cert_free(ss->sess_cert);
759 	if (ss->peer != NULL) X509_free(ss->peer);
760 	if (ss->ciphers != NULL) sk_SSL_CIPHER_free(ss->ciphers);
761 #ifndef OPENSSL_NO_TLSEXT
762 	if (ss->tlsext_hostname != NULL) OPENSSL_free(ss->tlsext_hostname);
763 	if (ss->tlsext_tick != NULL) OPENSSL_free(ss->tlsext_tick);
764 #ifndef OPENSSL_NO_EC
765 	ss->tlsext_ecpointformatlist_length = 0;
766 	if (ss->tlsext_ecpointformatlist != NULL) OPENSSL_free(ss->tlsext_ecpointformatlist);
767 	ss->tlsext_ellipticcurvelist_length = 0;
768 	if (ss->tlsext_ellipticcurvelist != NULL) OPENSSL_free(ss->tlsext_ellipticcurvelist);
769 #endif /* OPENSSL_NO_EC */
770 #endif
771 #ifndef OPENSSL_NO_PSK
772 	if (ss->psk_identity_hint != NULL)
773 		OPENSSL_free(ss->psk_identity_hint);
774 	if (ss->psk_identity != NULL)
775 		OPENSSL_free(ss->psk_identity);
776 #endif
777 #ifndef OPENSSL_NO_SRP
778 	if (ss->srp_username != NULL)
779 		OPENSSL_free(ss->srp_username);
780 #endif
781 	OPENSSL_cleanse(ss,sizeof(*ss));
782 	OPENSSL_free(ss);
783 	}
784 
785 int SSL_set_session(SSL *s, SSL_SESSION *session)
786 	{
787 	int ret=0;
788 	const SSL_METHOD *meth;
789 
790 	if (session != NULL)
791 		{
792 		meth=s->ctx->method->get_ssl_method(session->ssl_version);
793 		if (meth == NULL)
794 			meth=s->method->get_ssl_method(session->ssl_version);
795 		if (meth == NULL)
796 			{
797 			SSLerr(SSL_F_SSL_SET_SESSION,SSL_R_UNABLE_TO_FIND_SSL_METHOD);
798 			return(0);
799 			}
800 
801 		if (meth != s->method)
802 			{
803 			if (!SSL_set_ssl_method(s,meth))
804 				return(0);
805 			}
806 
807 #ifndef OPENSSL_NO_KRB5
808                 if (s->kssl_ctx && !s->kssl_ctx->client_princ &&
809                     session->krb5_client_princ_len > 0)
810                 {
811                     s->kssl_ctx->client_princ = (char *)OPENSSL_malloc(session->krb5_client_princ_len + 1);
812                     memcpy(s->kssl_ctx->client_princ,session->krb5_client_princ,
813                             session->krb5_client_princ_len);
814                     s->kssl_ctx->client_princ[session->krb5_client_princ_len] = '\0';
815                 }
816 #endif /* OPENSSL_NO_KRB5 */
817 
818 		/* CRYPTO_w_lock(CRYPTO_LOCK_SSL);*/
819 		CRYPTO_add(&session->references,1,CRYPTO_LOCK_SSL_SESSION);
820 		if (s->session != NULL)
821 			SSL_SESSION_free(s->session);
822 		s->session=session;
823 		s->verify_result = s->session->verify_result;
824 		/* CRYPTO_w_unlock(CRYPTO_LOCK_SSL);*/
825 		ret=1;
826 		}
827 	else
828 		{
829 		if (s->session != NULL)
830 			{
831 			SSL_SESSION_free(s->session);
832 			s->session=NULL;
833 			}
834 
835 		meth=s->ctx->method;
836 		if (meth != s->method)
837 			{
838 			if (!SSL_set_ssl_method(s,meth))
839 				return(0);
840 			}
841 		ret=1;
842 		}
843 	return(ret);
844 	}
845 
846 long SSL_SESSION_set_timeout(SSL_SESSION *s, long t)
847 	{
848 	if (s == NULL) return(0);
849 	s->timeout=t;
850 	return(1);
851 	}
852 
853 long SSL_SESSION_get_timeout(const SSL_SESSION *s)
854 	{
855 	if (s == NULL) return(0);
856 	return(s->timeout);
857 	}
858 
859 long SSL_SESSION_get_time(const SSL_SESSION *s)
860 	{
861 	if (s == NULL) return(0);
862 	return(s->time);
863 	}
864 
865 long SSL_SESSION_set_time(SSL_SESSION *s, long t)
866 	{
867 	if (s == NULL) return(0);
868 	s->time=t;
869 	return(t);
870 	}
871 
872 X509 *SSL_SESSION_get0_peer(SSL_SESSION *s)
873 	{
874 	return s->peer;
875 	}
876 
877 int SSL_SESSION_set1_id_context(SSL_SESSION *s,const unsigned char *sid_ctx,
878 			       unsigned int sid_ctx_len)
879 	{
880 	if(sid_ctx_len > SSL_MAX_SID_CTX_LENGTH)
881 		{
882 		SSLerr(SSL_F_SSL_SESSION_SET1_ID_CONTEXT,SSL_R_SSL_SESSION_ID_CONTEXT_TOO_LONG);
883 		return 0;
884 		}
885 	s->sid_ctx_length=sid_ctx_len;
886 	memcpy(s->sid_ctx,sid_ctx,sid_ctx_len);
887 
888 	return 1;
889 	}
890 
891 long SSL_CTX_set_timeout(SSL_CTX *s, long t)
892 	{
893 	long l;
894 	if (s == NULL) return(0);
895 	l=s->session_timeout;
896 	s->session_timeout=t;
897 	return(l);
898 	}
899 
900 long SSL_CTX_get_timeout(const SSL_CTX *s)
901 	{
902 	if (s == NULL) return(0);
903 	return(s->session_timeout);
904 	}
905 
906 #ifndef OPENSSL_NO_TLSEXT
907 int SSL_set_session_secret_cb(SSL *s, int (*tls_session_secret_cb)(SSL *s, void *secret, int *secret_len,
908 	STACK_OF(SSL_CIPHER) *peer_ciphers, SSL_CIPHER **cipher, void *arg), void *arg)
909 	{
910 	if (s == NULL) return(0);
911 	s->tls_session_secret_cb = tls_session_secret_cb;
912 	s->tls_session_secret_cb_arg = arg;
913 	return(1);
914 	}
915 
916 int SSL_set_session_ticket_ext_cb(SSL *s, tls_session_ticket_ext_cb_fn cb,
917 				  void *arg)
918 	{
919 	if (s == NULL) return(0);
920 	s->tls_session_ticket_ext_cb = cb;
921 	s->tls_session_ticket_ext_cb_arg = arg;
922 	return(1);
923 	}
924 
925 int SSL_set_session_ticket_ext(SSL *s, void *ext_data, int ext_len)
926 	{
927 	if (s->version >= TLS1_VERSION)
928 		{
929 		if (s->tlsext_session_ticket)
930 			{
931 			OPENSSL_free(s->tlsext_session_ticket);
932 			s->tlsext_session_ticket = NULL;
933 			}
934 
935 		s->tlsext_session_ticket = OPENSSL_malloc(sizeof(TLS_SESSION_TICKET_EXT) + ext_len);
936 		if (!s->tlsext_session_ticket)
937 			{
938 			SSLerr(SSL_F_SSL_SET_SESSION_TICKET_EXT, ERR_R_MALLOC_FAILURE);
939 			return 0;
940 			}
941 
942 		if (ext_data)
943 			{
944 			s->tlsext_session_ticket->length = ext_len;
945 			s->tlsext_session_ticket->data = s->tlsext_session_ticket + 1;
946 			memcpy(s->tlsext_session_ticket->data, ext_data, ext_len);
947 			}
948 		else
949 			{
950 			s->tlsext_session_ticket->length = 0;
951 			s->tlsext_session_ticket->data = NULL;
952 			}
953 
954 		return 1;
955 		}
956 
957 	return 0;
958 	}
959 #endif /* OPENSSL_NO_TLSEXT */
960 
961 typedef struct timeout_param_st
962 	{
963 	SSL_CTX *ctx;
964 	long time;
965 	LHASH_OF(SSL_SESSION) *cache;
966 	} TIMEOUT_PARAM;
967 
968 static void timeout_doall_arg(SSL_SESSION *s, TIMEOUT_PARAM *p)
969 	{
970 	if ((p->time == 0) || (p->time > (s->time+s->timeout))) /* timeout */
971 		{
972 		/* The reason we don't call SSL_CTX_remove_session() is to
973 		 * save on locking overhead */
974 		(void)lh_SSL_SESSION_delete(p->cache,s);
975 		SSL_SESSION_list_remove(p->ctx,s);
976 		s->not_resumable=1;
977 		if (p->ctx->remove_session_cb != NULL)
978 			p->ctx->remove_session_cb(p->ctx,s);
979 		SSL_SESSION_free(s);
980 		}
981 	}
982 
983 static IMPLEMENT_LHASH_DOALL_ARG_FN(timeout, SSL_SESSION, TIMEOUT_PARAM)
984 
985 void SSL_CTX_flush_sessions(SSL_CTX *s, long t)
986 	{
987 	unsigned long i;
988 	TIMEOUT_PARAM tp;
989 
990 	tp.ctx=s;
991 	tp.cache=s->sessions;
992 	if (tp.cache == NULL) return;
993 	tp.time=t;
994 	CRYPTO_w_lock(CRYPTO_LOCK_SSL_CTX);
995 	i=CHECKED_LHASH_OF(SSL_SESSION, tp.cache)->down_load;
996 	CHECKED_LHASH_OF(SSL_SESSION, tp.cache)->down_load=0;
997 	lh_SSL_SESSION_doall_arg(tp.cache, LHASH_DOALL_ARG_FN(timeout),
998 				 TIMEOUT_PARAM, &tp);
999 	CHECKED_LHASH_OF(SSL_SESSION, tp.cache)->down_load=i;
1000 	CRYPTO_w_unlock(CRYPTO_LOCK_SSL_CTX);
1001 	}
1002 
1003 int ssl_clear_bad_session(SSL *s)
1004 	{
1005 	if (	(s->session != NULL) &&
1006 		!(s->shutdown & SSL_SENT_SHUTDOWN) &&
1007 		!(SSL_in_init(s) || SSL_in_before(s)))
1008 		{
1009 		SSL_CTX_remove_session(s->ctx,s->session);
1010 		return(1);
1011 		}
1012 	else
1013 		return(0);
1014 	}
1015 
1016 /* locked by SSL_CTX in the calling function */
1017 static void SSL_SESSION_list_remove(SSL_CTX *ctx, SSL_SESSION *s)
1018 	{
1019 	if ((s->next == NULL) || (s->prev == NULL)) return;
1020 
1021 	if (s->next == (SSL_SESSION *)&(ctx->session_cache_tail))
1022 		{ /* last element in list */
1023 		if (s->prev == (SSL_SESSION *)&(ctx->session_cache_head))
1024 			{ /* only one element in list */
1025 			ctx->session_cache_head=NULL;
1026 			ctx->session_cache_tail=NULL;
1027 			}
1028 		else
1029 			{
1030 			ctx->session_cache_tail=s->prev;
1031 			s->prev->next=(SSL_SESSION *)&(ctx->session_cache_tail);
1032 			}
1033 		}
1034 	else
1035 		{
1036 		if (s->prev == (SSL_SESSION *)&(ctx->session_cache_head))
1037 			{ /* first element in list */
1038 			ctx->session_cache_head=s->next;
1039 			s->next->prev=(SSL_SESSION *)&(ctx->session_cache_head);
1040 			}
1041 		else
1042 			{ /* middle of list */
1043 			s->next->prev=s->prev;
1044 			s->prev->next=s->next;
1045 			}
1046 		}
1047 	s->prev=s->next=NULL;
1048 	}
1049 
1050 static void SSL_SESSION_list_add(SSL_CTX *ctx, SSL_SESSION *s)
1051 	{
1052 	if ((s->next != NULL) && (s->prev != NULL))
1053 		SSL_SESSION_list_remove(ctx,s);
1054 
1055 	if (ctx->session_cache_head == NULL)
1056 		{
1057 		ctx->session_cache_head=s;
1058 		ctx->session_cache_tail=s;
1059 		s->prev=(SSL_SESSION *)&(ctx->session_cache_head);
1060 		s->next=(SSL_SESSION *)&(ctx->session_cache_tail);
1061 		}
1062 	else
1063 		{
1064 		s->next=ctx->session_cache_head;
1065 		s->next->prev=s;
1066 		s->prev=(SSL_SESSION *)&(ctx->session_cache_head);
1067 		ctx->session_cache_head=s;
1068 		}
1069 	}
1070 
1071 void SSL_CTX_sess_set_new_cb(SSL_CTX *ctx,
1072 	int (*cb)(struct ssl_st *ssl,SSL_SESSION *sess))
1073 	{
1074 	ctx->new_session_cb=cb;
1075 	}
1076 
1077 int (*SSL_CTX_sess_get_new_cb(SSL_CTX *ctx))(SSL *ssl, SSL_SESSION *sess)
1078 	{
1079 	return ctx->new_session_cb;
1080 	}
1081 
1082 void SSL_CTX_sess_set_remove_cb(SSL_CTX *ctx,
1083 	void (*cb)(SSL_CTX *ctx,SSL_SESSION *sess))
1084 	{
1085 	ctx->remove_session_cb=cb;
1086 	}
1087 
1088 void (*SSL_CTX_sess_get_remove_cb(SSL_CTX *ctx))(SSL_CTX * ctx,SSL_SESSION *sess)
1089 	{
1090 	return ctx->remove_session_cb;
1091 	}
1092 
1093 void SSL_CTX_sess_set_get_cb(SSL_CTX *ctx,
1094 	SSL_SESSION *(*cb)(struct ssl_st *ssl,
1095 	         unsigned char *data,int len,int *copy))
1096 	{
1097 	ctx->get_session_cb=cb;
1098 	}
1099 
1100 SSL_SESSION * (*SSL_CTX_sess_get_get_cb(SSL_CTX *ctx))(SSL *ssl,
1101 	         unsigned char *data,int len,int *copy)
1102 	{
1103 	return ctx->get_session_cb;
1104 	}
1105 
1106 void SSL_CTX_set_info_callback(SSL_CTX *ctx,
1107 	void (*cb)(const SSL *ssl,int type,int val))
1108 	{
1109 	ctx->info_callback=cb;
1110 	}
1111 
1112 void (*SSL_CTX_get_info_callback(SSL_CTX *ctx))(const SSL *ssl,int type,int val)
1113 	{
1114 	return ctx->info_callback;
1115 	}
1116 
1117 void SSL_CTX_set_client_cert_cb(SSL_CTX *ctx,
1118 	int (*cb)(SSL *ssl, X509 **x509, EVP_PKEY **pkey))
1119 	{
1120 	ctx->client_cert_cb=cb;
1121 	}
1122 
1123 int (*SSL_CTX_get_client_cert_cb(SSL_CTX *ctx))(SSL * ssl, X509 ** x509 , EVP_PKEY **pkey)
1124 	{
1125 	return ctx->client_cert_cb;
1126 	}
1127 
1128 #ifndef OPENSSL_NO_ENGINE
1129 int SSL_CTX_set_client_cert_engine(SSL_CTX *ctx, ENGINE *e)
1130 	{
1131 	if (!ENGINE_init(e))
1132 		{
1133 		SSLerr(SSL_F_SSL_CTX_SET_CLIENT_CERT_ENGINE, ERR_R_ENGINE_LIB);
1134 		return 0;
1135 		}
1136 	if(!ENGINE_get_ssl_client_cert_function(e))
1137 		{
1138 		SSLerr(SSL_F_SSL_CTX_SET_CLIENT_CERT_ENGINE, SSL_R_NO_CLIENT_CERT_METHOD);
1139 		ENGINE_finish(e);
1140 		return 0;
1141 		}
1142 	ctx->client_cert_engine = e;
1143 	return 1;
1144 	}
1145 #endif
1146 
1147 void SSL_CTX_set_cookie_generate_cb(SSL_CTX *ctx,
1148 	int (*cb)(SSL *ssl, unsigned char *cookie, unsigned int *cookie_len))
1149 	{
1150 	ctx->app_gen_cookie_cb=cb;
1151 	}
1152 
1153 void SSL_CTX_set_cookie_verify_cb(SSL_CTX *ctx,
1154 	int (*cb)(SSL *ssl, unsigned char *cookie, unsigned int cookie_len))
1155 	{
1156 	ctx->app_verify_cookie_cb=cb;
1157 	}
1158 
1159 IMPLEMENT_PEM_rw(SSL_SESSION, SSL_SESSION, PEM_STRING_SSL_SESSION, SSL_SESSION)
1160