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 *ssl_session_meth=NULL;
70 #if 1 /* traditional SSLeay behaviour */
71 SSL_SESSION *SSL_get_session(SSL *ssl)
75 #else /* suggested change: increase reference counter so that a session
76 * can later be set in a new SSL object.
78 * -- the modified function should have a new name (or old
79 * applications, including s_client, leak memory);
80 * -- the locking seems unnecessary given that SSL structures
81 * usually cannot be safely shared between threads anyway. */
82 SSL_SESSION *SSL_get_session(SSL *ssl)
85 /* Need to lock this all up rather than just use CRYPTO_add so that
86 * somebody doesn't free ssl->session between when we check it's
87 * non-null and when we up the reference count. */
88 CRYPTO_r_lock(CRYPTO_LOCK_SSL_SESSION);
92 CRYPTO_r_unlock(CRYPTO_LOCK_SSL_SESSION);
97 int SSL_SESSION_get_ex_new_index(long argl, char *argp, int (*new_func)(),
98 int (*dup_func)(), void (*free_func)())
101 return(CRYPTO_get_ex_new_index(ssl_session_num-1,
103 argl,argp,new_func,dup_func,free_func));
106 int SSL_SESSION_set_ex_data(SSL_SESSION *s, int idx, void *arg)
108 return(CRYPTO_set_ex_data(&s->ex_data,idx,arg));
111 void *SSL_SESSION_get_ex_data(SSL_SESSION *s, int idx)
113 return(CRYPTO_get_ex_data(&s->ex_data,idx));
116 SSL_SESSION *SSL_SESSION_new(void)
120 ss=(SSL_SESSION *)Malloc(sizeof(SSL_SESSION));
123 SSLerr(SSL_F_SSL_SESSION_NEW,ERR_R_MALLOC_FAILURE);
126 memset(ss,0,sizeof(SSL_SESSION));
128 ss->verify_result = 1; /* avoid 0 (= X509_V_OK) just in case */
130 ss->timeout=60*5+4; /* 5 minute timeout by default */
135 CRYPTO_new_ex_data(ssl_session_meth,(char *)ss,&ss->ex_data);
139 int ssl_get_new_session(SSL *s, int session)
141 /* This gets used by clients and servers. */
143 SSL_SESSION *ss=NULL;
145 if ((ss=SSL_SESSION_new()) == NULL) return(0);
147 /* If the context has a default timeout, use it */
148 if (s->ctx->session_timeout == 0)
149 ss->timeout=SSL_get_default_timeout(s);
151 ss->timeout=s->ctx->session_timeout;
153 if (s->session != NULL)
155 SSL_SESSION_free(s->session);
161 if (s->version == SSL2_VERSION)
163 ss->ssl_version=SSL2_VERSION;
164 ss->session_id_length=SSL2_SSL_SESSION_ID_LENGTH;
166 else if (s->version == SSL3_VERSION)
168 ss->ssl_version=SSL3_VERSION;
169 ss->session_id_length=SSL3_SSL_SESSION_ID_LENGTH;
171 else if (s->version == TLS1_VERSION)
173 ss->ssl_version=TLS1_VERSION;
174 ss->session_id_length=SSL3_SSL_SESSION_ID_LENGTH;
178 SSLerr(SSL_F_SSL_GET_NEW_SESSION,SSL_R_UNSUPPORTED_SSL_VERSION);
179 SSL_SESSION_free(ss);
187 RAND_bytes(ss->session_id,ss->session_id_length);
188 CRYPTO_r_lock(CRYPTO_LOCK_SSL_CTX);
189 r=(SSL_SESSION *)lh_retrieve(s->ctx->sessions,
191 CRYPTO_r_unlock(CRYPTO_LOCK_SSL_CTX);
192 if (r == NULL) break;
193 /* else - woops a session_id match */
194 /* XXX We should also check the external cache --
195 * but the probability of a collision is negligible, and
196 * we could not prevent the concurrent creation of sessions
197 * with identical IDs since we currently don't have means
198 * to atomically check whether a session ID already exists
199 * and make a reservation for it if it does not
200 * (this problem applies to the internal cache as well).
206 ss->session_id_length=0;
209 memcpy(ss->sid_ctx,s->sid_ctx,s->sid_ctx_length);
210 ss->sid_ctx_length=s->sid_ctx_length;
212 ss->ssl_version=s->version;
213 ss->verify_result = X509_V_OK;
218 int ssl_get_prev_session(SSL *s, unsigned char *session_id, int len)
220 /* This is used only by servers. */
222 SSL_SESSION *ret=NULL,data;
225 data.ssl_version=s->version;
226 data.session_id_length=len;
227 if (len > SSL_MAX_SSL_SESSION_ID_LENGTH)
229 memcpy(data.session_id,session_id,len);
231 if (!(s->ctx->session_cache_mode & SSL_SESS_CACHE_NO_INTERNAL_LOOKUP))
233 CRYPTO_r_lock(CRYPTO_LOCK_SSL_CTX);
234 ret=(SSL_SESSION *)lh_retrieve(s->ctx->sessions,(char *)&data);
236 /* don't allow other threads to steal it: */
237 CRYPTO_add(&ret->references,1,CRYPTO_LOCK_SSL_SESSION);
238 CRYPTO_r_unlock(CRYPTO_LOCK_SSL_CTX);
245 s->ctx->stats.sess_miss++;
247 if (s->ctx->get_session_cb != NULL
248 && (ret=s->ctx->get_session_cb(s,session_id,len,©))
251 s->ctx->stats.sess_cb_hit++;
253 /* Increment reference count now if the session callback
254 * asks us to do so (note that if the session structures
255 * returned by the callback are shared between threads,
256 * it must handle the reference count itself [i.e. copy == 0],
257 * or things won't be thread-safe). */
259 CRYPTO_add(&ret->references,1,CRYPTO_LOCK_SSL_SESSION);
261 /* The following should not return 1, otherwise,
262 * things are very strange */
263 SSL_CTX_add_session(s->ctx,ret);
269 /* Now ret is non-NULL, and we own one of its reference counts. */
271 if((s->verify_mode&SSL_VERIFY_PEER)
272 && (!s->sid_ctx_length || ret->sid_ctx_length != s->sid_ctx_length
273 || memcmp(ret->sid_ctx,s->sid_ctx,ret->sid_ctx_length)))
275 /* We've found the session named by the client, but we don't
276 * want to use it in this context. */
278 if (s->sid_ctx_length == 0)
280 /* application should have used SSL[_CTX]_set_session_id_context
281 * -- we could tolerate this and just pretend we never heard
282 * of this session, but then applications could effectively
283 * disable the session cache by accident without anyone noticing */
285 SSLerr(SSL_F_SSL_GET_PREV_SESSION,SSL_R_SESSION_ID_CONTEXT_UNINITIALIZED);
291 #if 0 /* The client cannot always know when a session is not appropriate,
292 * so we shouldn't generate an error message. */
294 SSLerr(SSL_F_SSL_GET_PREV_SESSION,SSL_R_ATTEMPT_TO_REUSE_SESSION_IN_DIFFERENT_CONTEXT);
296 goto err; /* treat like cache miss */
300 if (ret->cipher == NULL)
302 unsigned char buf[5],*p;
308 if ((ret->ssl_version>>8) == SSL3_VERSION_MAJOR)
309 ret->cipher=ssl_get_cipher_by_char(s,&(buf[2]));
311 ret->cipher=ssl_get_cipher_by_char(s,&(buf[1]));
312 if (ret->cipher == NULL)
317 #if 0 /* This is way too late. */
319 /* If a thread got the session, then 'swaped', and another got
320 * it and then due to a time-out decided to 'Free' it we could
321 * be in trouble. So I'll increment it now, then double decrement
322 * later - am I speaking rubbish?. */
323 CRYPTO_add(&ret->references,1,CRYPTO_LOCK_SSL_SESSION);
326 if ((long)(ret->time+ret->timeout) < (long)time(NULL)) /* timeout */
328 s->ctx->stats.sess_timeout++;
329 /* remove it from the cache */
330 SSL_CTX_remove_session(s->ctx,ret);
334 s->ctx->stats.sess_hit++;
336 /* ret->time=time(NULL); */ /* rezero timeout? */
337 /* again, just leave the session
338 * if it is the same session, we have just incremented and
339 * then decremented the reference count :-) */
340 if (s->session != NULL)
341 SSL_SESSION_free(s->session);
343 s->verify_result = s->session->verify_result;
348 SSL_SESSION_free(ret);
355 int SSL_CTX_add_session(SSL_CTX *ctx, SSL_SESSION *c)
360 /* add just 1 reference count for the SSL_CTX's session cache
361 * even though it has two ways of access: each session is in a
362 * doubly linked list and an lhash */
363 CRYPTO_add(&c->references,1,CRYPTO_LOCK_SSL_SESSION);
364 /* if session c is in already in cache, we take back the increment later */
366 CRYPTO_w_lock(CRYPTO_LOCK_SSL_CTX);
367 s=(SSL_SESSION *)lh_insert(ctx->sessions,(char *)c);
369 /* s != NULL iff we already had a session with the given PID.
370 * In this case, s == c should hold (then we did not really modify
371 * ctx->sessions), or we're in trouble. */
372 if (s != NULL && s != c)
374 /* We *are* in trouble ... */
375 SSL_SESSION_list_remove(ctx,s);
377 /* ... so pretend the other session did not exist in cache
378 * (we cannot handle two SSL_SESSION structures with identical
379 * session ID in the same cache, which could happen e.g. when
380 * two threads concurrently obtain the same session from an external
385 /* Put at the head of the queue unless it is already in the cache */
387 SSL_SESSION_list_add(ctx,c);
391 /* existing cache entry -- decrement previously incremented reference
392 * count because it already takes into account the cache */
394 SSL_SESSION_free(s); /* s == c */
399 /* new cache entry -- remove old ones if cache has become too large */
403 if (SSL_CTX_sess_get_cache_size(ctx) > 0)
405 while (SSL_CTX_sess_number(ctx) >
406 SSL_CTX_sess_get_cache_size(ctx))
408 if (!remove_session_lock(ctx,
409 ctx->session_cache_tail, 0))
412 ctx->stats.sess_cache_full++;
416 CRYPTO_w_unlock(CRYPTO_LOCK_SSL_CTX);
420 int SSL_CTX_remove_session(SSL_CTX *ctx, SSL_SESSION *c)
422 return remove_session_lock(ctx, c, 1);
425 static int remove_session_lock(SSL_CTX *ctx, SSL_SESSION *c, int lck)
430 if ((c != NULL) && (c->session_id_length != 0))
432 if(lck) CRYPTO_w_lock(CRYPTO_LOCK_SSL_CTX);
433 r=(SSL_SESSION *)lh_delete(ctx->sessions,(char *)c);
437 SSL_SESSION_list_remove(ctx,c);
440 if(lck) CRYPTO_w_unlock(CRYPTO_LOCK_SSL_CTX);
445 if (ctx->remove_session_cb != NULL)
446 ctx->remove_session_cb(ctx,r);
455 void SSL_SESSION_free(SSL_SESSION *ss)
462 i=CRYPTO_add(&ss->references,-1,CRYPTO_LOCK_SSL_SESSION);
464 REF_PRINT("SSL_SESSION",ss);
470 fprintf(stderr,"SSL_SESSION_free, bad reference count\n");
475 CRYPTO_free_ex_data(ssl_session_meth,(char *)ss,&ss->ex_data);
477 memset(ss->key_arg,0,SSL_MAX_KEY_ARG_LENGTH);
478 memset(ss->master_key,0,SSL_MAX_MASTER_KEY_LENGTH);
479 memset(ss->session_id,0,SSL_MAX_SSL_SESSION_ID_LENGTH);
480 if (ss->sess_cert != NULL) ssl_sess_cert_free(ss->sess_cert);
481 if (ss->peer != NULL) X509_free(ss->peer);
482 if (ss->ciphers != NULL) sk_SSL_CIPHER_free(ss->ciphers);
483 memset(ss,0,sizeof(*ss));
487 int SSL_set_session(SSL *s, SSL_SESSION *session)
494 meth=s->ctx->method->get_ssl_method(session->ssl_version);
496 meth=s->method->get_ssl_method(session->ssl_version);
499 SSLerr(SSL_F_SSL_SET_SESSION,SSL_R_UNABLE_TO_FIND_SSL_METHOD);
503 if (meth != s->method)
505 if (!SSL_set_ssl_method(s,meth))
507 if (s->ctx->session_timeout == 0)
508 session->timeout=SSL_get_default_timeout(s);
510 session->timeout=s->ctx->session_timeout;
513 /* CRYPTO_w_lock(CRYPTO_LOCK_SSL);*/
514 CRYPTO_add(&session->references,1,CRYPTO_LOCK_SSL_SESSION);
515 if (s->session != NULL)
516 SSL_SESSION_free(s->session);
518 /* CRYPTO_w_unlock(CRYPTO_LOCK_SSL);*/
523 if (s->session != NULL)
525 SSL_SESSION_free(s->session);
530 if (meth != s->method)
532 if (!SSL_set_ssl_method(s,meth))
540 long SSL_SESSION_set_timeout(SSL_SESSION *s, long t)
542 if (s == NULL) return(0);
547 long SSL_SESSION_get_timeout(SSL_SESSION *s)
549 if (s == NULL) return(0);
553 long SSL_SESSION_get_time(SSL_SESSION *s)
555 if (s == NULL) return(0);
559 long SSL_SESSION_set_time(SSL_SESSION *s, long t)
561 if (s == NULL) return(0);
566 long SSL_CTX_set_timeout(SSL_CTX *s, long t)
569 if (s == NULL) return(0);
570 l=s->session_timeout;
571 s->session_timeout=t;
575 long SSL_CTX_get_timeout(SSL_CTX *s)
577 if (s == NULL) return(0);
578 return(s->session_timeout);
581 typedef struct timeout_param_st
588 static void timeout(SSL_SESSION *s, TIMEOUT_PARAM *p)
590 if ((p->time == 0) || (p->time > (s->time+s->timeout))) /* timeout */
592 /* The reason we don't call SSL_CTX_remove_session() is to
593 * save on locking overhead */
594 lh_delete(p->cache,(char *)s);
595 SSL_SESSION_list_remove(p->ctx,s);
597 if (p->ctx->remove_session_cb != NULL)
598 p->ctx->remove_session_cb(p->ctx,s);
603 void SSL_CTX_flush_sessions(SSL_CTX *s, long t)
609 tp.cache=s->sessions;
610 if (tp.cache == NULL) return;
612 CRYPTO_w_lock(CRYPTO_LOCK_SSL_CTX);
613 i=tp.cache->down_load;
614 tp.cache->down_load=0;
615 lh_doall_arg(tp.cache,(void (*)())timeout,(char *)&tp);
616 tp.cache->down_load=i;
617 CRYPTO_w_unlock(CRYPTO_LOCK_SSL_CTX);
620 int ssl_clear_bad_session(SSL *s)
622 if ( (s->session != NULL) &&
623 !(s->shutdown & SSL_SENT_SHUTDOWN) &&
624 !(SSL_in_init(s) || SSL_in_before(s)))
626 SSL_CTX_remove_session(s->ctx,s->session);
633 /* locked by SSL_CTX in the calling function */
634 static void SSL_SESSION_list_remove(SSL_CTX *ctx, SSL_SESSION *s)
636 if ((s->next == NULL) || (s->prev == NULL)) return;
638 if (s->next == (SSL_SESSION *)&(ctx->session_cache_tail))
639 { /* last element in list */
640 if (s->prev == (SSL_SESSION *)&(ctx->session_cache_head))
641 { /* only one element in list */
642 ctx->session_cache_head=NULL;
643 ctx->session_cache_tail=NULL;
647 ctx->session_cache_tail=s->prev;
648 s->prev->next=(SSL_SESSION *)&(ctx->session_cache_tail);
653 if (s->prev == (SSL_SESSION *)&(ctx->session_cache_head))
654 { /* first element in list */
655 ctx->session_cache_head=s->next;
656 s->next->prev=(SSL_SESSION *)&(ctx->session_cache_head);
659 { /* middle of list */
660 s->next->prev=s->prev;
661 s->prev->next=s->next;
664 s->prev=s->next=NULL;
667 static void SSL_SESSION_list_add(SSL_CTX *ctx, SSL_SESSION *s)
669 if ((s->next != NULL) && (s->prev != NULL))
670 SSL_SESSION_list_remove(ctx,s);
672 if (ctx->session_cache_head == NULL)
674 ctx->session_cache_head=s;
675 ctx->session_cache_tail=s;
676 s->prev=(SSL_SESSION *)&(ctx->session_cache_head);
677 s->next=(SSL_SESSION *)&(ctx->session_cache_tail);
681 s->next=ctx->session_cache_head;
683 s->prev=(SSL_SESSION *)&(ctx->session_cache_head);
684 ctx->session_cache_head=s;