2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
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.
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).
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.
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
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)"
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
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.]
60 #include <openssl/lhash.h>
61 #include <openssl/rand.h>
64 static void SSL_SESSION_list_remove(SSL_CTX *ctx, SSL_SESSION *s);
65 static void SSL_SESSION_list_add(SSL_CTX *ctx,SSL_SESSION *s);
66 static int remove_session_lock(SSL_CTX *ctx, SSL_SESSION *c, int lck);
67 static int ssl_session_num=0;
68 static STACK_OF(CRYPTO_EX_DATA_FUNCS) *ssl_session_meth=NULL;
70 SSL_SESSION *SSL_get_session(SSL *ssl)
71 /* aka SSL_get0_session; gets 0 objects, just returns a copy of the pointer */
76 SSL_SESSION *SSL_get1_session(SSL *ssl)
77 /* variant of SSL_get_session: caller really gets something */
80 /* Need to lock this all up rather than just use CRYPTO_add so that
81 * somebody doesn't free ssl->session between when we check it's
82 * non-null and when we up the reference count. */
83 CRYPTO_r_lock(CRYPTO_LOCK_SSL_SESSION);
87 CRYPTO_r_unlock(CRYPTO_LOCK_SSL_SESSION);
91 int SSL_SESSION_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,
92 CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func)
95 return(CRYPTO_get_ex_new_index(ssl_session_num-1,
97 argl,argp,new_func,dup_func,free_func));
100 int SSL_SESSION_set_ex_data(SSL_SESSION *s, int idx, void *arg)
102 return(CRYPTO_set_ex_data(&s->ex_data,idx,arg));
105 void *SSL_SESSION_get_ex_data(SSL_SESSION *s, int idx)
107 return(CRYPTO_get_ex_data(&s->ex_data,idx));
110 SSL_SESSION *SSL_SESSION_new(void)
114 ss=(SSL_SESSION *)OPENSSL_malloc(sizeof(SSL_SESSION));
117 SSLerr(SSL_F_SSL_SESSION_NEW,ERR_R_MALLOC_FAILURE);
120 memset(ss,0,sizeof(SSL_SESSION));
122 ss->verify_result = 1; /* avoid 0 (= X509_V_OK) just in case */
124 ss->timeout=60*5+4; /* 5 minute timeout by default */
129 CRYPTO_new_ex_data(ssl_session_meth,ss,&ss->ex_data);
133 int ssl_get_new_session(SSL *s, int session)
135 /* This gets used by clients and servers. */
137 SSL_SESSION *ss=NULL;
139 if ((ss=SSL_SESSION_new()) == NULL) return(0);
141 /* If the context has a default timeout, use it */
142 if (s->ctx->session_timeout == 0)
143 ss->timeout=SSL_get_default_timeout(s);
145 ss->timeout=s->ctx->session_timeout;
147 if (s->session != NULL)
149 SSL_SESSION_free(s->session);
155 if (s->version == SSL2_VERSION)
157 ss->ssl_version=SSL2_VERSION;
158 ss->session_id_length=SSL2_SSL_SESSION_ID_LENGTH;
160 else if (s->version == SSL3_VERSION)
162 ss->ssl_version=SSL3_VERSION;
163 ss->session_id_length=SSL3_SSL_SESSION_ID_LENGTH;
165 else if (s->version == TLS1_VERSION)
167 ss->ssl_version=TLS1_VERSION;
168 ss->session_id_length=SSL3_SSL_SESSION_ID_LENGTH;
172 SSLerr(SSL_F_SSL_GET_NEW_SESSION,SSL_R_UNSUPPORTED_SSL_VERSION);
173 SSL_SESSION_free(ss);
181 RAND_pseudo_bytes(ss->session_id,ss->session_id_length);
182 CRYPTO_r_lock(CRYPTO_LOCK_SSL_CTX);
183 r=(SSL_SESSION *)lh_retrieve(s->ctx->sessions, ss);
184 CRYPTO_r_unlock(CRYPTO_LOCK_SSL_CTX);
185 if (r == NULL) break;
186 /* else - woops a session_id match */
187 /* XXX We should also check the external cache --
188 * but the probability of a collision is negligible, and
189 * we could not prevent the concurrent creation of sessions
190 * with identical IDs since we currently don't have means
191 * to atomically check whether a session ID already exists
192 * and make a reservation for it if it does not
193 * (this problem applies to the internal cache as well).
199 ss->session_id_length=0;
202 memcpy(ss->sid_ctx,s->sid_ctx,s->sid_ctx_length);
203 ss->sid_ctx_length=s->sid_ctx_length;
205 ss->ssl_version=s->version;
206 ss->verify_result = X509_V_OK;
211 int ssl_get_prev_session(SSL *s, unsigned char *session_id, int len)
213 /* This is used only by servers. */
215 SSL_SESSION *ret=NULL,data;
218 data.ssl_version=s->version;
219 data.session_id_length=len;
220 if (len > SSL_MAX_SSL_SESSION_ID_LENGTH)
222 memcpy(data.session_id,session_id,len);
224 if (!(s->ctx->session_cache_mode & SSL_SESS_CACHE_NO_INTERNAL_LOOKUP))
226 CRYPTO_r_lock(CRYPTO_LOCK_SSL_CTX);
227 ret=(SSL_SESSION *)lh_retrieve(s->ctx->sessions,&data);
229 /* don't allow other threads to steal it: */
230 CRYPTO_add(&ret->references,1,CRYPTO_LOCK_SSL_SESSION);
231 CRYPTO_r_unlock(CRYPTO_LOCK_SSL_CTX);
238 s->ctx->stats.sess_miss++;
240 if (s->ctx->get_session_cb != NULL
241 && (ret=s->ctx->get_session_cb(s,session_id,len,©))
244 s->ctx->stats.sess_cb_hit++;
246 /* Increment reference count now if the session callback
247 * asks us to do so (note that if the session structures
248 * returned by the callback are shared between threads,
249 * it must handle the reference count itself [i.e. copy == 0],
250 * or things won't be thread-safe). */
252 CRYPTO_add(&ret->references,1,CRYPTO_LOCK_SSL_SESSION);
254 /* The following should not return 1, otherwise,
255 * things are very strange */
256 SSL_CTX_add_session(s->ctx,ret);
262 /* Now ret is non-NULL, and we own one of its reference counts. */
264 if((s->verify_mode&SSL_VERIFY_PEER)
265 && (!s->sid_ctx_length || ret->sid_ctx_length != s->sid_ctx_length
266 || memcmp(ret->sid_ctx,s->sid_ctx,ret->sid_ctx_length)))
268 /* We've found the session named by the client, but we don't
269 * want to use it in this context. */
271 if (s->sid_ctx_length == 0)
273 /* application should have used SSL[_CTX]_set_session_id_context
274 * -- we could tolerate this and just pretend we never heard
275 * of this session, but then applications could effectively
276 * disable the session cache by accident without anyone noticing */
278 SSLerr(SSL_F_SSL_GET_PREV_SESSION,SSL_R_SESSION_ID_CONTEXT_UNINITIALIZED);
284 #if 0 /* The client cannot always know when a session is not appropriate,
285 * so we shouldn't generate an error message. */
287 SSLerr(SSL_F_SSL_GET_PREV_SESSION,SSL_R_ATTEMPT_TO_REUSE_SESSION_IN_DIFFERENT_CONTEXT);
289 goto err; /* treat like cache miss */
293 if (ret->cipher == NULL)
295 unsigned char buf[5],*p;
301 if ((ret->ssl_version>>8) == SSL3_VERSION_MAJOR)
302 ret->cipher=ssl_get_cipher_by_char(s,&(buf[2]));
304 ret->cipher=ssl_get_cipher_by_char(s,&(buf[1]));
305 if (ret->cipher == NULL)
310 #if 0 /* This is way too late. */
312 /* If a thread got the session, then 'swaped', and another got
313 * it and then due to a time-out decided to 'OPENSSL_free' it we could
314 * be in trouble. So I'll increment it now, then double decrement
315 * later - am I speaking rubbish?. */
316 CRYPTO_add(&ret->references,1,CRYPTO_LOCK_SSL_SESSION);
319 if ((long)(ret->time+ret->timeout) < (long)time(NULL)) /* timeout */
321 s->ctx->stats.sess_timeout++;
322 /* remove it from the cache */
323 SSL_CTX_remove_session(s->ctx,ret);
327 s->ctx->stats.sess_hit++;
329 /* ret->time=time(NULL); */ /* rezero timeout? */
330 /* again, just leave the session
331 * if it is the same session, we have just incremented and
332 * then decremented the reference count :-) */
333 if (s->session != NULL)
334 SSL_SESSION_free(s->session);
336 s->verify_result = s->session->verify_result;
341 SSL_SESSION_free(ret);
348 int SSL_CTX_add_session(SSL_CTX *ctx, SSL_SESSION *c)
353 /* add just 1 reference count for the SSL_CTX's session cache
354 * even though it has two ways of access: each session is in a
355 * doubly linked list and an lhash */
356 CRYPTO_add(&c->references,1,CRYPTO_LOCK_SSL_SESSION);
357 /* if session c is in already in cache, we take back the increment later */
359 CRYPTO_w_lock(CRYPTO_LOCK_SSL_CTX);
360 s=(SSL_SESSION *)lh_insert(ctx->sessions,c);
362 /* s != NULL iff we already had a session with the given PID.
363 * In this case, s == c should hold (then we did not really modify
364 * ctx->sessions), or we're in trouble. */
365 if (s != NULL && s != c)
367 /* We *are* in trouble ... */
368 SSL_SESSION_list_remove(ctx,s);
370 /* ... so pretend the other session did not exist in cache
371 * (we cannot handle two SSL_SESSION structures with identical
372 * session ID in the same cache, which could happen e.g. when
373 * two threads concurrently obtain the same session from an external
378 /* Put at the head of the queue unless it is already in the cache */
380 SSL_SESSION_list_add(ctx,c);
384 /* existing cache entry -- decrement previously incremented reference
385 * count because it already takes into account the cache */
387 SSL_SESSION_free(s); /* s == c */
392 /* new cache entry -- remove old ones if cache has become too large */
396 if (SSL_CTX_sess_get_cache_size(ctx) > 0)
398 while (SSL_CTX_sess_number(ctx) >
399 SSL_CTX_sess_get_cache_size(ctx))
401 if (!remove_session_lock(ctx,
402 ctx->session_cache_tail, 0))
405 ctx->stats.sess_cache_full++;
409 CRYPTO_w_unlock(CRYPTO_LOCK_SSL_CTX);
413 int SSL_CTX_remove_session(SSL_CTX *ctx, SSL_SESSION *c)
415 return remove_session_lock(ctx, c, 1);
418 static int remove_session_lock(SSL_CTX *ctx, SSL_SESSION *c, int lck)
423 if ((c != NULL) && (c->session_id_length != 0))
425 if(lck) CRYPTO_w_lock(CRYPTO_LOCK_SSL_CTX);
426 r=(SSL_SESSION *)lh_delete(ctx->sessions,c);
430 SSL_SESSION_list_remove(ctx,c);
433 if(lck) CRYPTO_w_unlock(CRYPTO_LOCK_SSL_CTX);
438 if (ctx->remove_session_cb != NULL)
439 ctx->remove_session_cb(ctx,r);
448 void SSL_SESSION_free(SSL_SESSION *ss)
455 i=CRYPTO_add(&ss->references,-1,CRYPTO_LOCK_SSL_SESSION);
457 REF_PRINT("SSL_SESSION",ss);
463 fprintf(stderr,"SSL_SESSION_free, bad reference count\n");
468 CRYPTO_free_ex_data(ssl_session_meth,ss,&ss->ex_data);
470 memset(ss->key_arg,0,SSL_MAX_KEY_ARG_LENGTH);
471 memset(ss->master_key,0,SSL_MAX_MASTER_KEY_LENGTH);
472 memset(ss->session_id,0,SSL_MAX_SSL_SESSION_ID_LENGTH);
473 if (ss->sess_cert != NULL) ssl_sess_cert_free(ss->sess_cert);
474 if (ss->peer != NULL) X509_free(ss->peer);
475 if (ss->ciphers != NULL) sk_SSL_CIPHER_free(ss->ciphers);
476 memset(ss,0,sizeof(*ss));
480 int SSL_set_session(SSL *s, SSL_SESSION *session)
487 meth=s->ctx->method->get_ssl_method(session->ssl_version);
489 meth=s->method->get_ssl_method(session->ssl_version);
492 SSLerr(SSL_F_SSL_SET_SESSION,SSL_R_UNABLE_TO_FIND_SSL_METHOD);
496 if (meth != s->method)
498 if (!SSL_set_ssl_method(s,meth))
500 if (s->ctx->session_timeout == 0)
501 session->timeout=SSL_get_default_timeout(s);
503 session->timeout=s->ctx->session_timeout;
506 /* CRYPTO_w_lock(CRYPTO_LOCK_SSL);*/
507 CRYPTO_add(&session->references,1,CRYPTO_LOCK_SSL_SESSION);
508 if (s->session != NULL)
509 SSL_SESSION_free(s->session);
511 s->verify_result = s->session->verify_result;
512 /* CRYPTO_w_unlock(CRYPTO_LOCK_SSL);*/
517 if (s->session != NULL)
519 SSL_SESSION_free(s->session);
524 if (meth != s->method)
526 if (!SSL_set_ssl_method(s,meth))
534 long SSL_SESSION_set_timeout(SSL_SESSION *s, long t)
536 if (s == NULL) return(0);
541 long SSL_SESSION_get_timeout(SSL_SESSION *s)
543 if (s == NULL) return(0);
547 long SSL_SESSION_get_time(SSL_SESSION *s)
549 if (s == NULL) return(0);
553 long SSL_SESSION_set_time(SSL_SESSION *s, long t)
555 if (s == NULL) return(0);
560 long SSL_CTX_set_timeout(SSL_CTX *s, long t)
563 if (s == NULL) return(0);
564 l=s->session_timeout;
565 s->session_timeout=t;
569 long SSL_CTX_get_timeout(SSL_CTX *s)
571 if (s == NULL) return(0);
572 return(s->session_timeout);
575 typedef struct timeout_param_st
582 static void timeout(SSL_SESSION *s, TIMEOUT_PARAM *p)
584 if ((p->time == 0) || (p->time > (s->time+s->timeout))) /* timeout */
586 /* The reason we don't call SSL_CTX_remove_session() is to
587 * save on locking overhead */
588 lh_delete(p->cache,s);
589 SSL_SESSION_list_remove(p->ctx,s);
591 if (p->ctx->remove_session_cb != NULL)
592 p->ctx->remove_session_cb(p->ctx,s);
597 void SSL_CTX_flush_sessions(SSL_CTX *s, long t)
603 tp.cache=s->sessions;
604 if (tp.cache == NULL) return;
606 CRYPTO_w_lock(CRYPTO_LOCK_SSL_CTX);
607 i=tp.cache->down_load;
608 tp.cache->down_load=0;
609 lh_doall_arg(tp.cache,(void (*)())timeout,&tp);
610 tp.cache->down_load=i;
611 CRYPTO_w_unlock(CRYPTO_LOCK_SSL_CTX);
614 int ssl_clear_bad_session(SSL *s)
616 if ( (s->session != NULL) &&
617 !(s->shutdown & SSL_SENT_SHUTDOWN) &&
618 !(SSL_in_init(s) || SSL_in_before(s)))
620 SSL_CTX_remove_session(s->ctx,s->session);
627 /* locked by SSL_CTX in the calling function */
628 static void SSL_SESSION_list_remove(SSL_CTX *ctx, SSL_SESSION *s)
630 if ((s->next == NULL) || (s->prev == NULL)) return;
632 if (s->next == (SSL_SESSION *)&(ctx->session_cache_tail))
633 { /* last element in list */
634 if (s->prev == (SSL_SESSION *)&(ctx->session_cache_head))
635 { /* only one element in list */
636 ctx->session_cache_head=NULL;
637 ctx->session_cache_tail=NULL;
641 ctx->session_cache_tail=s->prev;
642 s->prev->next=(SSL_SESSION *)&(ctx->session_cache_tail);
647 if (s->prev == (SSL_SESSION *)&(ctx->session_cache_head))
648 { /* first element in list */
649 ctx->session_cache_head=s->next;
650 s->next->prev=(SSL_SESSION *)&(ctx->session_cache_head);
653 { /* middle of list */
654 s->next->prev=s->prev;
655 s->prev->next=s->next;
658 s->prev=s->next=NULL;
661 static void SSL_SESSION_list_add(SSL_CTX *ctx, SSL_SESSION *s)
663 if ((s->next != NULL) && (s->prev != NULL))
664 SSL_SESSION_list_remove(ctx,s);
666 if (ctx->session_cache_head == NULL)
668 ctx->session_cache_head=s;
669 ctx->session_cache_tail=s;
670 s->prev=(SSL_SESSION *)&(ctx->session_cache_head);
671 s->next=(SSL_SESSION *)&(ctx->session_cache_tail);
675 s->next=ctx->session_cache_head;
677 s->prev=(SSL_SESSION *)&(ctx->session_cache_head);
678 ctx->session_cache_head=s;