xref: /freebsd/crypto/openssl/ssl/ssl_sess.c (revision 830940567b49bb0c08dfaed40418999e76616909)
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 #include <stdio.h>
60 #include <openssl/lhash.h>
61 #include <openssl/rand.h>
62 #ifndef OPENSSL_NO_ENGINE
63 #include <openssl/engine.h>
64 #endif
65 #include "ssl_locl.h"
66 
67 static void SSL_SESSION_list_remove(SSL_CTX *ctx, SSL_SESSION *s);
68 static void SSL_SESSION_list_add(SSL_CTX *ctx,SSL_SESSION *s);
69 static int remove_session_lock(SSL_CTX *ctx, SSL_SESSION *c, int lck);
70 
71 SSL_SESSION *SSL_get_session(const SSL *ssl)
72 /* aka SSL_get0_session; gets 0 objects, just returns a copy of the pointer */
73 	{
74 	return(ssl->session);
75 	}
76 
77 SSL_SESSION *SSL_get1_session(SSL *ssl)
78 /* variant of SSL_get_session: caller really gets something */
79 	{
80 	SSL_SESSION *sess;
81 	/* Need to lock this all up rather than just use CRYPTO_add so that
82 	 * somebody doesn't free ssl->session between when we check it's
83 	 * non-null and when we up the reference count. */
84 	CRYPTO_w_lock(CRYPTO_LOCK_SSL_SESSION);
85 	sess = ssl->session;
86 	if(sess)
87 		sess->references++;
88 	CRYPTO_w_unlock(CRYPTO_LOCK_SSL_SESSION);
89 	return(sess);
90 	}
91 
92 int SSL_SESSION_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,
93 	     CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func)
94 	{
95 	return CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_SSL_SESSION, argl, argp,
96 			new_func, dup_func, free_func);
97 	}
98 
99 int SSL_SESSION_set_ex_data(SSL_SESSION *s, int idx, void *arg)
100 	{
101 	return(CRYPTO_set_ex_data(&s->ex_data,idx,arg));
102 	}
103 
104 void *SSL_SESSION_get_ex_data(const SSL_SESSION *s, int idx)
105 	{
106 	return(CRYPTO_get_ex_data(&s->ex_data,idx));
107 	}
108 
109 SSL_SESSION *SSL_SESSION_new(void)
110 	{
111 	SSL_SESSION *ss;
112 
113 	ss=(SSL_SESSION *)OPENSSL_malloc(sizeof(SSL_SESSION));
114 	if (ss == NULL)
115 		{
116 		SSLerr(SSL_F_SSL_SESSION_NEW,ERR_R_MALLOC_FAILURE);
117 		return(0);
118 		}
119 	memset(ss,0,sizeof(SSL_SESSION));
120 
121 	ss->verify_result = 1; /* avoid 0 (= X509_V_OK) just in case */
122 	ss->references=1;
123 	ss->timeout=60*5+4; /* 5 minute timeout by default */
124 	ss->time=(unsigned long)time(NULL);
125 	ss->prev=NULL;
126 	ss->next=NULL;
127 	ss->compress_meth=0;
128 #ifndef OPENSSL_NO_TLSEXT
129 	ss->tlsext_hostname = NULL;
130 #endif
131 	CRYPTO_new_ex_data(CRYPTO_EX_INDEX_SSL_SESSION, ss, &ss->ex_data);
132 	return(ss);
133 	}
134 
135 const unsigned char *SSL_SESSION_get_id(const SSL_SESSION *s, unsigned int *len)
136 	{
137 	if(len)
138 		*len = s->session_id_length;
139 	return s->session_id;
140 	}
141 
142 /* Even with SSLv2, we have 16 bytes (128 bits) of session ID space. SSLv3/TLSv1
143  * has 32 bytes (256 bits). As such, filling the ID with random gunk repeatedly
144  * until we have no conflict is going to complete in one iteration pretty much
145  * "most" of the time (btw: understatement). So, if it takes us 10 iterations
146  * and we still can't avoid a conflict - well that's a reasonable point to call
147  * it quits. Either the RAND code is broken or someone is trying to open roughly
148  * very close to 2^128 (or 2^256) SSL sessions to our server. How you might
149  * store that many sessions is perhaps a more interesting question ... */
150 
151 #define MAX_SESS_ID_ATTEMPTS 10
152 static int def_generate_session_id(const SSL *ssl, unsigned char *id,
153 				unsigned int *id_len)
154 {
155 	unsigned int retry = 0;
156 	do
157 		if (RAND_pseudo_bytes(id, *id_len) <= 0)
158 			return 0;
159 	while(SSL_has_matching_session_id(ssl, id, *id_len) &&
160 		(++retry < MAX_SESS_ID_ATTEMPTS));
161 	if(retry < MAX_SESS_ID_ATTEMPTS)
162 		return 1;
163 	/* else - woops a session_id match */
164 	/* XXX We should also check the external cache --
165 	 * but the probability of a collision is negligible, and
166 	 * we could not prevent the concurrent creation of sessions
167 	 * with identical IDs since we currently don't have means
168 	 * to atomically check whether a session ID already exists
169 	 * and make a reservation for it if it does not
170 	 * (this problem applies to the internal cache as well).
171 	 */
172 	return 0;
173 }
174 
175 int ssl_get_new_session(SSL *s, int session)
176 	{
177 	/* This gets used by clients and servers. */
178 
179 	unsigned int tmp;
180 	SSL_SESSION *ss=NULL;
181 	GEN_SESSION_CB cb = def_generate_session_id;
182 
183 	if ((ss=SSL_SESSION_new()) == NULL) return(0);
184 
185 	/* If the context has a default timeout, use it */
186 	if (s->ctx->session_timeout == 0)
187 		ss->timeout=SSL_get_default_timeout(s);
188 	else
189 		ss->timeout=s->ctx->session_timeout;
190 
191 	if (s->session != NULL)
192 		{
193 		SSL_SESSION_free(s->session);
194 		s->session=NULL;
195 		}
196 
197 	if (session)
198 		{
199 		if (s->version == SSL2_VERSION)
200 			{
201 			ss->ssl_version=SSL2_VERSION;
202 			ss->session_id_length=SSL2_SSL_SESSION_ID_LENGTH;
203 			}
204 		else if (s->version == SSL3_VERSION)
205 			{
206 			ss->ssl_version=SSL3_VERSION;
207 			ss->session_id_length=SSL3_SSL_SESSION_ID_LENGTH;
208 			}
209 		else if (s->version == TLS1_VERSION)
210 			{
211 			ss->ssl_version=TLS1_VERSION;
212 			ss->session_id_length=SSL3_SSL_SESSION_ID_LENGTH;
213 			}
214 		else if (s->version == DTLS1_VERSION)
215 			{
216 			ss->ssl_version=DTLS1_VERSION;
217 			ss->session_id_length=SSL3_SSL_SESSION_ID_LENGTH;
218 			}
219 		else
220 			{
221 			SSLerr(SSL_F_SSL_GET_NEW_SESSION,SSL_R_UNSUPPORTED_SSL_VERSION);
222 			SSL_SESSION_free(ss);
223 			return(0);
224 			}
225 #ifndef OPENSSL_NO_TLSEXT
226 		/* If RFC4507 ticket use empty session ID */
227 		if (s->tlsext_ticket_expected)
228 			{
229 			ss->session_id_length = 0;
230 			goto sess_id_done;
231 			}
232 #endif
233 		/* Choose which callback will set the session ID */
234 		CRYPTO_r_lock(CRYPTO_LOCK_SSL_CTX);
235 		if(s->generate_session_id)
236 			cb = s->generate_session_id;
237 		else if(s->ctx->generate_session_id)
238 			cb = s->ctx->generate_session_id;
239 		CRYPTO_r_unlock(CRYPTO_LOCK_SSL_CTX);
240 		/* Choose a session ID */
241 		tmp = ss->session_id_length;
242 		if(!cb(s, ss->session_id, &tmp))
243 			{
244 			/* The callback failed */
245 			SSLerr(SSL_F_SSL_GET_NEW_SESSION,
246 				SSL_R_SSL_SESSION_ID_CALLBACK_FAILED);
247 			SSL_SESSION_free(ss);
248 			return(0);
249 			}
250 		/* Don't allow the callback to set the session length to zero.
251 		 * nor set it higher than it was. */
252 		if(!tmp || (tmp > ss->session_id_length))
253 			{
254 			/* The callback set an illegal length */
255 			SSLerr(SSL_F_SSL_GET_NEW_SESSION,
256 				SSL_R_SSL_SESSION_ID_HAS_BAD_LENGTH);
257 			SSL_SESSION_free(ss);
258 			return(0);
259 			}
260 		/* If the session length was shrunk and we're SSLv2, pad it */
261 		if((tmp < ss->session_id_length) && (s->version == SSL2_VERSION))
262 			memset(ss->session_id + tmp, 0, ss->session_id_length - tmp);
263 		else
264 			ss->session_id_length = tmp;
265 		/* Finally, check for a conflict */
266 		if(SSL_has_matching_session_id(s, ss->session_id,
267 						ss->session_id_length))
268 			{
269 			SSLerr(SSL_F_SSL_GET_NEW_SESSION,
270 				SSL_R_SSL_SESSION_ID_CONFLICT);
271 			SSL_SESSION_free(ss);
272 			return(0);
273 			}
274 #ifndef OPENSSL_NO_TLSEXT
275 		sess_id_done:
276 		if (s->tlsext_hostname) {
277 			ss->tlsext_hostname = BUF_strdup(s->tlsext_hostname);
278 			if (ss->tlsext_hostname == NULL) {
279 				SSLerr(SSL_F_SSL_GET_NEW_SESSION, ERR_R_INTERNAL_ERROR);
280 				SSL_SESSION_free(ss);
281 				return 0;
282 				}
283 			}
284 #endif
285 		}
286 	else
287 		{
288 		ss->session_id_length=0;
289 		}
290 
291 	if (s->sid_ctx_length > sizeof ss->sid_ctx)
292 		{
293 		SSLerr(SSL_F_SSL_GET_NEW_SESSION, ERR_R_INTERNAL_ERROR);
294 		SSL_SESSION_free(ss);
295 		return 0;
296 		}
297 	memcpy(ss->sid_ctx,s->sid_ctx,s->sid_ctx_length);
298 	ss->sid_ctx_length=s->sid_ctx_length;
299 	s->session=ss;
300 	ss->ssl_version=s->version;
301 	ss->verify_result = X509_V_OK;
302 
303 	return(1);
304 	}
305 
306 int ssl_get_prev_session(SSL *s, unsigned char *session_id, int len,
307 			const unsigned char *limit)
308 	{
309 	/* This is used only by servers. */
310 
311 	SSL_SESSION *ret=NULL;
312 	int fatal = 0;
313 #ifndef OPENSSL_NO_TLSEXT
314 	int r;
315 #endif
316 
317 	if (len > SSL_MAX_SSL_SESSION_ID_LENGTH)
318 		goto err;
319 #ifndef OPENSSL_NO_TLSEXT
320  	r = tls1_process_ticket(s, session_id, len, limit, &ret);
321 	if (r == -1)
322 		{
323 		fatal = 1;
324  		goto err;
325 		}
326 	else if (r == 0 || (!ret && !len))
327 		goto err;
328 	else if (!ret && !(s->session_ctx->session_cache_mode & SSL_SESS_CACHE_NO_INTERNAL_LOOKUP))
329 #else
330 	if (len == 0)
331 		goto err;
332 	if (!(s->ctx->session_cache_mode & SSL_SESS_CACHE_NO_INTERNAL_LOOKUP))
333 #endif
334 		{
335 		SSL_SESSION data;
336 		data.ssl_version=s->version;
337 		data.session_id_length=len;
338 		if (len == 0)
339 			return 0;
340  		memcpy(data.session_id,session_id,len);
341 		CRYPTO_r_lock(CRYPTO_LOCK_SSL_CTX);
342 		ret=(SSL_SESSION *)lh_retrieve(s->ctx->sessions,&data);
343 		if (ret != NULL)
344 		    /* don't allow other threads to steal it: */
345 		    CRYPTO_add(&ret->references,1,CRYPTO_LOCK_SSL_SESSION);
346 		CRYPTO_r_unlock(CRYPTO_LOCK_SSL_CTX);
347 		}
348 
349 	if (ret == NULL)
350 		{
351 		int copy=1;
352 
353 		s->ctx->stats.sess_miss++;
354 		ret=NULL;
355 		if (s->ctx->get_session_cb != NULL
356 		    && (ret=s->ctx->get_session_cb(s,session_id,len,&copy))
357 		       != NULL)
358 			{
359 			s->ctx->stats.sess_cb_hit++;
360 
361 			/* Increment reference count now if the session callback
362 			 * asks us to do so (note that if the session structures
363 			 * returned by the callback are shared between threads,
364 			 * it must handle the reference count itself [i.e. copy == 0],
365 			 * or things won't be thread-safe). */
366 			if (copy)
367 				CRYPTO_add(&ret->references,1,CRYPTO_LOCK_SSL_SESSION);
368 
369 			/* Add the externally cached session to the internal
370 			 * cache as well if and only if we are supposed to. */
371 			if(!(s->ctx->session_cache_mode & SSL_SESS_CACHE_NO_INTERNAL_STORE))
372 				/* The following should not return 1, otherwise,
373 				 * things are very strange */
374 				SSL_CTX_add_session(s->ctx,ret);
375 			}
376 		if (ret == NULL)
377 			goto err;
378 		}
379 
380 	/* Now ret is non-NULL, and we own one of its reference counts. */
381 
382 	if (ret->sid_ctx_length != s->sid_ctx_length
383 	    || memcmp(ret->sid_ctx,s->sid_ctx,ret->sid_ctx_length))
384 		{
385 		/* We've found the session named by the client, but we don't
386 		 * want to use it in this context. */
387 
388 #if 0 /* The client cannot always know when a session is not appropriate,
389        * so we shouldn't generate an error message. */
390 
391 		SSLerr(SSL_F_SSL_GET_PREV_SESSION,SSL_R_ATTEMPT_TO_REUSE_SESSION_IN_DIFFERENT_CONTEXT);
392 #endif
393 		goto err; /* treat like cache miss */
394 		}
395 
396 	if((s->verify_mode & SSL_VERIFY_PEER) && s->sid_ctx_length == 0)
397 		{
398 		/* We can't be sure if this session is being used out of
399 		 * context, which is especially important for SSL_VERIFY_PEER.
400 		 * The application should have used SSL[_CTX]_set_session_id_context.
401 		 *
402 		 * For this error case, we generate an error instead of treating
403 		 * the event like a cache miss (otherwise it would be easy for
404 		 * applications to effectively disable the session cache by
405 		 * accident without anyone noticing).
406 		 */
407 
408 		SSLerr(SSL_F_SSL_GET_PREV_SESSION,SSL_R_SESSION_ID_CONTEXT_UNINITIALIZED);
409 		fatal = 1;
410 		goto err;
411 		}
412 
413 	if (ret->cipher == NULL)
414 		{
415 		unsigned char buf[5],*p;
416 		unsigned long l;
417 
418 		p=buf;
419 		l=ret->cipher_id;
420 		l2n(l,p);
421 		if ((ret->ssl_version>>8) == SSL3_VERSION_MAJOR)
422 			ret->cipher=ssl_get_cipher_by_char(s,&(buf[2]));
423 		else
424 			ret->cipher=ssl_get_cipher_by_char(s,&(buf[1]));
425 		if (ret->cipher == NULL)
426 			goto err;
427 		}
428 
429 
430 #if 0 /* This is way too late. */
431 
432 	/* If a thread got the session, then 'swaped', and another got
433 	 * it and then due to a time-out decided to 'OPENSSL_free' it we could
434 	 * be in trouble.  So I'll increment it now, then double decrement
435 	 * later - am I speaking rubbish?. */
436 	CRYPTO_add(&ret->references,1,CRYPTO_LOCK_SSL_SESSION);
437 #endif
438 
439 	if (ret->timeout < (long)(time(NULL) - ret->time)) /* timeout */
440 		{
441 		s->ctx->stats.sess_timeout++;
442 		/* remove it from the cache */
443 		SSL_CTX_remove_session(s->ctx,ret);
444 		goto err;
445 		}
446 
447 	s->ctx->stats.sess_hit++;
448 
449 	/* ret->time=time(NULL); */ /* rezero timeout? */
450 	/* again, just leave the session
451 	 * if it is the same session, we have just incremented and
452 	 * then decremented the reference count :-) */
453 	if (s->session != NULL)
454 		SSL_SESSION_free(s->session);
455 	s->session=ret;
456 	s->verify_result = s->session->verify_result;
457 	return(1);
458 
459  err:
460 	if (ret != NULL)
461 		SSL_SESSION_free(ret);
462 	if (fatal)
463 		return -1;
464 	else
465 		return 0;
466 	}
467 
468 int SSL_CTX_add_session(SSL_CTX *ctx, SSL_SESSION *c)
469 	{
470 	int ret=0;
471 	SSL_SESSION *s;
472 
473 	/* add just 1 reference count for the SSL_CTX's session cache
474 	 * even though it has two ways of access: each session is in a
475 	 * doubly linked list and an lhash */
476 	CRYPTO_add(&c->references,1,CRYPTO_LOCK_SSL_SESSION);
477 	/* if session c is in already in cache, we take back the increment later */
478 
479 	CRYPTO_w_lock(CRYPTO_LOCK_SSL_CTX);
480 	s=(SSL_SESSION *)lh_insert(ctx->sessions,c);
481 
482 	/* s != NULL iff we already had a session with the given PID.
483 	 * In this case, s == c should hold (then we did not really modify
484 	 * ctx->sessions), or we're in trouble. */
485 	if (s != NULL && s != c)
486 		{
487 		/* We *are* in trouble ... */
488 		SSL_SESSION_list_remove(ctx,s);
489 		SSL_SESSION_free(s);
490 		/* ... so pretend the other session did not exist in cache
491 		 * (we cannot handle two SSL_SESSION structures with identical
492 		 * session ID in the same cache, which could happen e.g. when
493 		 * two threads concurrently obtain the same session from an external
494 		 * cache) */
495 		s = NULL;
496 		}
497 
498  	/* Put at the head of the queue unless it is already in the cache */
499 	if (s == NULL)
500 		SSL_SESSION_list_add(ctx,c);
501 
502 	if (s != NULL)
503 		{
504 		/* existing cache entry -- decrement previously incremented reference
505 		 * count because it already takes into account the cache */
506 
507 		SSL_SESSION_free(s); /* s == c */
508 		ret=0;
509 		}
510 	else
511 		{
512 		/* new cache entry -- remove old ones if cache has become too large */
513 
514 		ret=1;
515 
516 		if (SSL_CTX_sess_get_cache_size(ctx) > 0)
517 			{
518 			while (SSL_CTX_sess_number(ctx) >
519 				SSL_CTX_sess_get_cache_size(ctx))
520 				{
521 				if (!remove_session_lock(ctx,
522 					ctx->session_cache_tail, 0))
523 					break;
524 				else
525 					ctx->stats.sess_cache_full++;
526 				}
527 			}
528 		}
529 	CRYPTO_w_unlock(CRYPTO_LOCK_SSL_CTX);
530 	return(ret);
531 	}
532 
533 int SSL_CTX_remove_session(SSL_CTX *ctx, SSL_SESSION *c)
534 {
535 	return remove_session_lock(ctx, c, 1);
536 }
537 
538 static int remove_session_lock(SSL_CTX *ctx, SSL_SESSION *c, int lck)
539 	{
540 	SSL_SESSION *r;
541 	int ret=0;
542 
543 	if ((c != NULL) && (c->session_id_length != 0))
544 		{
545 		if(lck) CRYPTO_w_lock(CRYPTO_LOCK_SSL_CTX);
546 		if ((r = (SSL_SESSION *)lh_retrieve(ctx->sessions,c)) == c)
547 			{
548 			ret=1;
549 			r=(SSL_SESSION *)lh_delete(ctx->sessions,c);
550 			SSL_SESSION_list_remove(ctx,c);
551 			}
552 
553 		if(lck) CRYPTO_w_unlock(CRYPTO_LOCK_SSL_CTX);
554 
555 		if (ret)
556 			{
557 			r->not_resumable=1;
558 			if (ctx->remove_session_cb != NULL)
559 				ctx->remove_session_cb(ctx,r);
560 			SSL_SESSION_free(r);
561 			}
562 		}
563 	else
564 		ret=0;
565 	return(ret);
566 	}
567 
568 void SSL_SESSION_free(SSL_SESSION *ss)
569 	{
570 	int i;
571 
572 	if(ss == NULL)
573 	    return;
574 
575 	i=CRYPTO_add(&ss->references,-1,CRYPTO_LOCK_SSL_SESSION);
576 #ifdef REF_PRINT
577 	REF_PRINT("SSL_SESSION",ss);
578 #endif
579 	if (i > 0) return;
580 #ifdef REF_CHECK
581 	if (i < 0)
582 		{
583 		fprintf(stderr,"SSL_SESSION_free, bad reference count\n");
584 		abort(); /* ok */
585 		}
586 #endif
587 
588 	CRYPTO_free_ex_data(CRYPTO_EX_INDEX_SSL_SESSION, ss, &ss->ex_data);
589 
590 	OPENSSL_cleanse(ss->key_arg,sizeof ss->key_arg);
591 	OPENSSL_cleanse(ss->master_key,sizeof ss->master_key);
592 	OPENSSL_cleanse(ss->session_id,sizeof ss->session_id);
593 	if (ss->sess_cert != NULL) ssl_sess_cert_free(ss->sess_cert);
594 	if (ss->peer != NULL) X509_free(ss->peer);
595 	if (ss->ciphers != NULL) sk_SSL_CIPHER_free(ss->ciphers);
596 #ifndef OPENSSL_NO_TLSEXT
597 	if (ss->tlsext_hostname != NULL) OPENSSL_free(ss->tlsext_hostname);
598 	if (ss->tlsext_tick != NULL) OPENSSL_free(ss->tlsext_tick);
599 #endif
600 	OPENSSL_cleanse(ss,sizeof(*ss));
601 	OPENSSL_free(ss);
602 	}
603 
604 int SSL_set_session(SSL *s, SSL_SESSION *session)
605 	{
606 	int ret=0;
607 	SSL_METHOD *meth;
608 
609 	if (session != NULL)
610 		{
611 		meth=s->ctx->method->get_ssl_method(session->ssl_version);
612 		if (meth == NULL)
613 			meth=s->method->get_ssl_method(session->ssl_version);
614 		if (meth == NULL)
615 			{
616 			SSLerr(SSL_F_SSL_SET_SESSION,SSL_R_UNABLE_TO_FIND_SSL_METHOD);
617 			return(0);
618 			}
619 
620 		if (meth != s->method)
621 			{
622 			if (!SSL_set_ssl_method(s,meth))
623 				return(0);
624 			if (s->ctx->session_timeout == 0)
625 				session->timeout=SSL_get_default_timeout(s);
626 			else
627 				session->timeout=s->ctx->session_timeout;
628 			}
629 
630 #ifndef OPENSSL_NO_KRB5
631                 if (s->kssl_ctx && !s->kssl_ctx->client_princ &&
632                     session->krb5_client_princ_len > 0)
633                 {
634                     s->kssl_ctx->client_princ = (char *)OPENSSL_malloc(session->krb5_client_princ_len + 1);
635                     memcpy(s->kssl_ctx->client_princ,session->krb5_client_princ,
636                             session->krb5_client_princ_len);
637                     s->kssl_ctx->client_princ[session->krb5_client_princ_len] = '\0';
638                 }
639 #endif /* OPENSSL_NO_KRB5 */
640 
641 		/* CRYPTO_w_lock(CRYPTO_LOCK_SSL);*/
642 		CRYPTO_add(&session->references,1,CRYPTO_LOCK_SSL_SESSION);
643 		if (s->session != NULL)
644 			SSL_SESSION_free(s->session);
645 		s->session=session;
646 		s->verify_result = s->session->verify_result;
647 		/* CRYPTO_w_unlock(CRYPTO_LOCK_SSL);*/
648 		ret=1;
649 		}
650 	else
651 		{
652 		if (s->session != NULL)
653 			{
654 			SSL_SESSION_free(s->session);
655 			s->session=NULL;
656 			}
657 
658 		meth=s->ctx->method;
659 		if (meth != s->method)
660 			{
661 			if (!SSL_set_ssl_method(s,meth))
662 				return(0);
663 			}
664 		ret=1;
665 		}
666 	return(ret);
667 	}
668 
669 long SSL_SESSION_set_timeout(SSL_SESSION *s, long t)
670 	{
671 	if (s == NULL) return(0);
672 	s->timeout=t;
673 	return(1);
674 	}
675 
676 long SSL_SESSION_get_timeout(const SSL_SESSION *s)
677 	{
678 	if (s == NULL) return(0);
679 	return(s->timeout);
680 	}
681 
682 long SSL_SESSION_get_time(const SSL_SESSION *s)
683 	{
684 	if (s == NULL) return(0);
685 	return(s->time);
686 	}
687 
688 long SSL_SESSION_set_time(SSL_SESSION *s, long t)
689 	{
690 	if (s == NULL) return(0);
691 	s->time=t;
692 	return(t);
693 	}
694 
695 long SSL_CTX_set_timeout(SSL_CTX *s, long t)
696 	{
697 	long l;
698 	if (s == NULL) return(0);
699 	l=s->session_timeout;
700 	s->session_timeout=t;
701 	return(l);
702 	}
703 
704 long SSL_CTX_get_timeout(const SSL_CTX *s)
705 	{
706 	if (s == NULL) return(0);
707 	return(s->session_timeout);
708 	}
709 
710 typedef struct timeout_param_st
711 	{
712 	SSL_CTX *ctx;
713 	long time;
714 	LHASH *cache;
715 	} TIMEOUT_PARAM;
716 
717 static void timeout(SSL_SESSION *s, TIMEOUT_PARAM *p)
718 	{
719 	if ((p->time == 0) || (p->time > (s->time+s->timeout))) /* timeout */
720 		{
721 		/* The reason we don't call SSL_CTX_remove_session() is to
722 		 * save on locking overhead */
723 		lh_delete(p->cache,s);
724 		SSL_SESSION_list_remove(p->ctx,s);
725 		s->not_resumable=1;
726 		if (p->ctx->remove_session_cb != NULL)
727 			p->ctx->remove_session_cb(p->ctx,s);
728 		SSL_SESSION_free(s);
729 		}
730 	}
731 
732 static IMPLEMENT_LHASH_DOALL_ARG_FN(timeout, SSL_SESSION *, TIMEOUT_PARAM *)
733 
734 void SSL_CTX_flush_sessions(SSL_CTX *s, long t)
735 	{
736 	unsigned long i;
737 	TIMEOUT_PARAM tp;
738 
739 	tp.ctx=s;
740 	tp.cache=s->sessions;
741 	if (tp.cache == NULL) return;
742 	tp.time=t;
743 	CRYPTO_w_lock(CRYPTO_LOCK_SSL_CTX);
744 	i=tp.cache->down_load;
745 	tp.cache->down_load=0;
746 	lh_doall_arg(tp.cache, LHASH_DOALL_ARG_FN(timeout), &tp);
747 	tp.cache->down_load=i;
748 	CRYPTO_w_unlock(CRYPTO_LOCK_SSL_CTX);
749 	}
750 
751 int ssl_clear_bad_session(SSL *s)
752 	{
753 	if (	(s->session != NULL) &&
754 		!(s->shutdown & SSL_SENT_SHUTDOWN) &&
755 		!(SSL_in_init(s) || SSL_in_before(s)))
756 		{
757 		SSL_CTX_remove_session(s->ctx,s->session);
758 		return(1);
759 		}
760 	else
761 		return(0);
762 	}
763 
764 /* locked by SSL_CTX in the calling function */
765 static void SSL_SESSION_list_remove(SSL_CTX *ctx, SSL_SESSION *s)
766 	{
767 	if ((s->next == NULL) || (s->prev == NULL)) return;
768 
769 	if (s->next == (SSL_SESSION *)&(ctx->session_cache_tail))
770 		{ /* last element in list */
771 		if (s->prev == (SSL_SESSION *)&(ctx->session_cache_head))
772 			{ /* only one element in list */
773 			ctx->session_cache_head=NULL;
774 			ctx->session_cache_tail=NULL;
775 			}
776 		else
777 			{
778 			ctx->session_cache_tail=s->prev;
779 			s->prev->next=(SSL_SESSION *)&(ctx->session_cache_tail);
780 			}
781 		}
782 	else
783 		{
784 		if (s->prev == (SSL_SESSION *)&(ctx->session_cache_head))
785 			{ /* first element in list */
786 			ctx->session_cache_head=s->next;
787 			s->next->prev=(SSL_SESSION *)&(ctx->session_cache_head);
788 			}
789 		else
790 			{ /* middle of list */
791 			s->next->prev=s->prev;
792 			s->prev->next=s->next;
793 			}
794 		}
795 	s->prev=s->next=NULL;
796 	}
797 
798 static void SSL_SESSION_list_add(SSL_CTX *ctx, SSL_SESSION *s)
799 	{
800 	if ((s->next != NULL) && (s->prev != NULL))
801 		SSL_SESSION_list_remove(ctx,s);
802 
803 	if (ctx->session_cache_head == NULL)
804 		{
805 		ctx->session_cache_head=s;
806 		ctx->session_cache_tail=s;
807 		s->prev=(SSL_SESSION *)&(ctx->session_cache_head);
808 		s->next=(SSL_SESSION *)&(ctx->session_cache_tail);
809 		}
810 	else
811 		{
812 		s->next=ctx->session_cache_head;
813 		s->next->prev=s;
814 		s->prev=(SSL_SESSION *)&(ctx->session_cache_head);
815 		ctx->session_cache_head=s;
816 		}
817 	}
818 
819 void SSL_CTX_sess_set_new_cb(SSL_CTX *ctx,
820 	int (*cb)(struct ssl_st *ssl,SSL_SESSION *sess))
821 	{
822 	ctx->new_session_cb=cb;
823 	}
824 
825 int (*SSL_CTX_sess_get_new_cb(SSL_CTX *ctx))(SSL *ssl, SSL_SESSION *sess)
826 	{
827 	return ctx->new_session_cb;
828 	}
829 
830 void SSL_CTX_sess_set_remove_cb(SSL_CTX *ctx,
831 	void (*cb)(SSL_CTX *ctx,SSL_SESSION *sess))
832 	{
833 	ctx->remove_session_cb=cb;
834 	}
835 
836 void (*SSL_CTX_sess_get_remove_cb(SSL_CTX *ctx))(SSL_CTX * ctx,SSL_SESSION *sess)
837 	{
838 	return ctx->remove_session_cb;
839 	}
840 
841 void SSL_CTX_sess_set_get_cb(SSL_CTX *ctx,
842 	SSL_SESSION *(*cb)(struct ssl_st *ssl,
843 	         unsigned char *data,int len,int *copy))
844 	{
845 	ctx->get_session_cb=cb;
846 	}
847 
848 SSL_SESSION * (*SSL_CTX_sess_get_get_cb(SSL_CTX *ctx))(SSL *ssl,
849 	         unsigned char *data,int len,int *copy)
850 	{
851 	return ctx->get_session_cb;
852 	}
853 
854 void SSL_CTX_set_info_callback(SSL_CTX *ctx,
855 	void (*cb)(const SSL *ssl,int type,int val))
856 	{
857 	ctx->info_callback=cb;
858 	}
859 
860 void (*SSL_CTX_get_info_callback(SSL_CTX *ctx))(const SSL *ssl,int type,int val)
861 	{
862 	return ctx->info_callback;
863 	}
864 
865 void SSL_CTX_set_client_cert_cb(SSL_CTX *ctx,
866 	int (*cb)(SSL *ssl, X509 **x509, EVP_PKEY **pkey))
867 	{
868 	ctx->client_cert_cb=cb;
869 	}
870 
871 int (*SSL_CTX_get_client_cert_cb(SSL_CTX *ctx))(SSL * ssl, X509 ** x509 , EVP_PKEY **pkey)
872 	{
873 	return ctx->client_cert_cb;
874 	}
875 
876 #ifndef OPENSSL_NO_ENGINE
877 int SSL_CTX_set_client_cert_engine(SSL_CTX *ctx, ENGINE *e)
878 	{
879 	if (!ENGINE_init(e))
880 		{
881 		SSLerr(SSL_F_SSL_CTX_SET_CLIENT_CERT_ENGINE, ERR_R_ENGINE_LIB);
882 		return 0;
883 		}
884 	if(!ENGINE_get_ssl_client_cert_function(e))
885 		{
886 		SSLerr(SSL_F_SSL_CTX_SET_CLIENT_CERT_ENGINE, SSL_R_NO_CLIENT_CERT_METHOD);
887 		ENGINE_finish(e);
888 		return 0;
889 		}
890 	ctx->client_cert_engine = e;
891 	return 1;
892 	}
893 #endif
894 
895 void SSL_CTX_set_cookie_generate_cb(SSL_CTX *ctx,
896 	int (*cb)(SSL *ssl, unsigned char *cookie, unsigned int *cookie_len))
897 	{
898 	ctx->app_gen_cookie_cb=cb;
899 	}
900 
901 void SSL_CTX_set_cookie_verify_cb(SSL_CTX *ctx,
902 	int (*cb)(SSL *ssl, unsigned char *cookie, unsigned int cookie_len))
903 	{
904 	ctx->app_verify_cookie_cb=cb;
905 	}
906 
907