ssl/ssl_sess.c

   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 "lhash.h"
  61 #include "rand.h"
  62 #include "ssl_locl.h"
  63
  64 #ifndef NOPROTO
  65 static void SSL_SESSION_list_remove(SSL_CTX *ctx, SSL_SESSION *s);
  66 static void SSL_SESSION_list_add(SSL_CTX *ctx,SSL_SESSION *s);
  67 #else
  68 static void SSL_SESSION_list_remove();
  69 static void SSL_SESSION_list_add();
  70 #endif
  71
  72 static int ssl_session_num=0;
  73 static STACK *ssl_session_meth=NULL;
  74
  75 SSL_SESSION *SSL_get_session(ssl)
  76 SSL *ssl;
  77         {
  78         return(ssl->session);
  79         }
  80
  81 int SSL_SESSION_get_ex_new_index(argl,argp,new_func,dup_func,free_func)
  82 long argl;
  83 char *argp;
  84 int (*new_func)();
  85 int (*dup_func)();
  86 void (*free_func)();
  87         {
  88         ssl_session_num++;
  89         return(CRYPTO_get_ex_new_index(ssl_session_num-1,
  90                 &ssl_session_meth,
  91                 argl,argp,new_func,dup_func,free_func));
  92         }
  93
  94 int SSL_SESSION_set_ex_data(s,idx,arg)
  95 SSL_SESSION *s;
  96 int idx;
  97 void *arg;
  98         {
  99         return(CRYPTO_set_ex_data(&s->ex_data,idx,arg));
 100         }
 101
 102 void *SSL_SESSION_get_ex_data(s,idx)
 103 SSL_SESSION *s;
 104 int idx;
 105         {
 106         return(CRYPTO_get_ex_data(&s->ex_data,idx));
 107         }
 108
 109 SSL_SESSION *SSL_SESSION_new()
 110         {
 111         SSL_SESSION *ss;
 112
 113         ss=(SSL_SESSION *)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->references=1;
 122         ss->timeout=60*5+4; /* 5 minute timeout by default */
 123         ss->time=time(NULL);
 124         ss->prev=NULL;
 125         ss->next=NULL;
 126         ss->compress_meth=0;
 127         CRYPTO_new_ex_data(ssl_session_meth,(char *)ss,&ss->ex_data);
 128         return(ss);
 129         }
 130
 131 int ssl_get_new_session(s, session)
 132 SSL *s;
 133 int session;
 134         {
 135         SSL_SESSION *ss=NULL;
 136
 137         if ((ss=SSL_SESSION_new()) == NULL) return(0);
 138
 139         /* If the context has a default timeout, use it */
 140         if (s->ctx->session_timeout == 0)
 141                 ss->timeout=SSL_get_default_timeout(s);
 142         else
 143                 ss->timeout=s->ctx->session_timeout;
 144
 145         if (s->session != NULL)
 146                 {
 147                 SSL_SESSION_free(s->session);
 148                 s->session=NULL;
 149                 }
 150
 151         if (session)
 152                 {
 153                 if (s->version == SSL2_CLIENT_VERSION)
 154                         {
 155                         ss->ssl_version=SSL2_VERSION;
 156                         ss->session_id_length=SSL2_SSL_SESSION_ID_LENGTH;
 157                         }
 158                 else if (s->version == SSL3_VERSION)
 159                         {
 160                         ss->ssl_version=SSL3_VERSION;
 161                         ss->session_id_length=SSL3_SSL_SESSION_ID_LENGTH;
 162                         }
 163                 else if (s->version == TLS1_VERSION)
 164                         {
 165                         ss->ssl_version=TLS1_VERSION;
 166                         ss->session_id_length=SSL3_SSL_SESSION_ID_LENGTH;
 167                         }
 168                 else
 169                         {
 170                         SSLerr(SSL_F_SSL_GET_NEW_SESSION,SSL_R_UNSUPPORTED_SSL_VERSION);
 171                         SSL_SESSION_free(ss);
 172                         return(0);
 173                         }
 174
 175                 for (;;)
 176                         {
 177                         SSL_SESSION *r;
 178
 179                         RAND_bytes(ss->session_id,ss->session_id_length);
 180                         CRYPTO_r_lock(CRYPTO_LOCK_SSL_CTX);
 181                         r=(SSL_SESSION *)lh_retrieve(s->ctx->sessions,
 182                                 (char *)ss);
 183                         CRYPTO_r_unlock(CRYPTO_LOCK_SSL_CTX);
 184                         if (r == NULL) break;
 185                         /* else - woops a session_id match */
 186                         }
 187                 }
 188         else
 189                 {
 190                 ss->session_id_length=0;
 191                 }
 192
 193         memcpy(ss->sid_ctx,s->sid_ctx,s->sid_ctx_length);
 194         ss->sid_ctx_length=s->sid_ctx_length;
 195         s->session=ss;
 196         ss->ssl_version=s->version;
 197
 198         return(1);
 199         }
 200
 201 int ssl_get_prev_session(s,session_id,len)
 202 SSL *s;
 203 unsigned char *session_id;
 204 int len;
 205         {
 206         SSL_SESSION *ret=NULL,data;
 207         int copy=1;
 208
 209         /* conn_init();*/
 210         data.ssl_version=s->version;
 211         data.session_id_length=len;
 212         if (len > SSL_MAX_SSL_SESSION_ID_LENGTH)
 213                 return(0);
 214         memcpy(data.session_id,session_id,len);
 215
 216         if (!(s->ctx->session_cache_mode & SSL_SESS_CACHE_NO_INTERNAL_LOOKUP))
 217                 {
 218                 CRYPTO_r_lock(CRYPTO_LOCK_SSL_CTX);
 219                 ret=(SSL_SESSION *)lh_retrieve(s->ctx->sessions,(char *)&data);
 220                 CRYPTO_r_unlock(CRYPTO_LOCK_SSL_CTX);
 221                 }
 222
 223         if (ret == NULL)
 224                 {
 225                 s->ctx->stats.sess_miss++;
 226                 ret=NULL;
 227                 if (s->ctx->get_session_cb != NULL
 228                     && (ret=s->ctx->get_session_cb(s,session_id,len,&copy))
 229                        != NULL)
 230                         {
 231                         s->ctx->stats.sess_cb_hit++;
 232
 233                         /* The following should not return 1, otherwise,
 234                          * things are very strange */
 235                         SSL_CTX_add_session(s->ctx,ret);
 236                         }
 237                 if (ret == NULL) return(0);
 238                 }
 239
 240         if((s->verify_mode&SSL_VERIFY_PEER)
 241            && (!s->sid_ctx_length || ret->sid_ctx_length != s->sid_ctx_length
 242                || memcmp(ret->sid_ctx,s->sid_ctx,ret->sid_ctx_length)))
 243             {
 244             SSLerr(SSL_F_SSL_GET_PREV_SESSION,SSL_R_ATTEMPT_TO_REUSE_SESSION_IN_DIFFERENT_CONTEXT);
 245             return 0;
 246             }
 247
 248         /* auto free it */
 249         if (!copy)
 250             SSL_SESSION_free(ret);
 251
 252         if (ret->cipher == NULL)
 253                 {
 254                 char buf[5],*p;
 255                 unsigned long l;
 256
 257                 p=buf;
 258                 l=ret->cipher_id;
 259                 l2n(l,p);
 260                 if ((ret->ssl_version>>8) == SSL3_VERSION_MAJOR)
 261                         ret->cipher=ssl_get_cipher_by_char(s,&(buf[2]));
 262                 else
 263                         ret->cipher=ssl_get_cipher_by_char(s,&(buf[1]));
 264                 if (ret->cipher == NULL)
 265                         return(0);
 266                 }
 267
 268         /* If a thread got the session, then 'swaped', and another got
 269          * it and then due to a time-out decided to 'Free' it we could
 270          * be in trouble.  So I'll increment it now, then double decrement
 271          * later - am I speaking rubbish?. */
 272         CRYPTO_add(&ret->references,1,CRYPTO_LOCK_SSL_SESSION);
 273
 274         if ((long)(ret->time+ret->timeout) < (long)time(NULL)) /* timeout */
 275                 {
 276                 s->ctx->stats.sess_timeout++;
 277                 /* remove it from the cache */
 278                 SSL_CTX_remove_session(s->ctx,ret);
 279                 SSL_SESSION_free(ret);          /* again to actually Free it */
 280                 return(0);
 281                 }
 282
 283         s->ctx->stats.sess_hit++;
 284
 285         /* ret->time=time(NULL); */ /* rezero timeout? */
 286         /* again, just leave the session
 287          * if it is the same session, we have just incremented and
 288          * then decremented the reference count :-) */
 289         if (s->session != NULL)
 290                 SSL_SESSION_free(s->session);
 291         s->session=ret;
 292         return(1);
 293         }
 294
 295 int SSL_CTX_add_session(ctx,c)
 296 SSL_CTX *ctx;
 297 SSL_SESSION *c;
 298         {
 299         int ret=0;
 300         SSL_SESSION *s;
 301
 302         /* conn_init(); */
 303         CRYPTO_add(&c->references,1,CRYPTO_LOCK_SSL_SESSION);
 304
 305         CRYPTO_w_lock(CRYPTO_LOCK_SSL_CTX);
 306         s=(SSL_SESSION *)lh_insert(ctx->sessions,(char *)c);
 307
 308         /* Put on the end of the queue unless it is already in the cache */
 309         if (s == NULL)
 310                 SSL_SESSION_list_add(ctx,c);
 311
 312         /* If the same session if is being 're-added', Free the old
 313          * one when the last person stops using it.
 314          * This will also work if it is alread in the cache.
 315          * The references will go up and then down :-) */
 316         if (s != NULL)
 317                 {
 318                 SSL_SESSION_free(s);
 319                 ret=0;
 320                 }
 321         else
 322                 {
 323                 ret=1;
 324
 325                 if (SSL_CTX_sess_get_cache_size(ctx) > 0)
 326                         {
 327                         while (SSL_CTX_sess_number(ctx) >
 328                                 SSL_CTX_sess_get_cache_size(ctx))
 329                                 {
 330                                 if (!SSL_CTX_remove_session(ctx,
 331                                         ctx->session_cache_tail))
 332                                         break;
 333                                 else
 334                                         ctx->stats.sess_cache_full++;
 335                                 }
 336                         }
 337                 }
 338         CRYPTO_w_unlock(CRYPTO_LOCK_SSL_CTX);
 339         return(ret);
 340         }
 341
 342 int SSL_CTX_remove_session(ctx,c)
 343 SSL_CTX *ctx;
 344 SSL_SESSION *c;
 345         {
 346         SSL_SESSION *r;
 347         int ret=0;
 348
 349         if ((c != NULL) && (c->session_id_length != 0))
 350                 {
 351                 CRYPTO_w_lock(CRYPTO_LOCK_SSL_CTX);
 352                 r=(SSL_SESSION *)lh_delete(ctx->sessions,(char *)c);
 353                 if (r != NULL)
 354                         {
 355                         ret=1;
 356                         SSL_SESSION_list_remove(ctx,c);
 357                         }
 358
 359                 CRYPTO_w_unlock(CRYPTO_LOCK_SSL_CTX);
 360
 361                 if (ret)
 362                         {
 363                         r->not_resumable=1;
 364                         if (ctx->remove_session_cb != NULL)
 365                                 ctx->remove_session_cb(ctx,r);
 366                         SSL_SESSION_free(r);
 367                         }
 368                 }
 369         else
 370                 ret=0;
 371         return(ret);
 372         }
 373
 374 void SSL_SESSION_free(ss)
 375 SSL_SESSION *ss;
 376         {
 377         int i;
 378
 379         if(ss == NULL)
 380             return;
 381
 382         i=CRYPTO_add(&ss->references,-1,CRYPTO_LOCK_SSL_SESSION);
 383 #ifdef REF_PRINT
 384         REF_PRINT("SSL_SESSION",ss);
 385 #endif
 386         if (i > 0) return;
 387 #ifdef REF_CHECK
 388         if (i < 0)
 389                 {
 390                 fprintf(stderr,"SSL_SESSION_free, bad reference count\n");
 391                 abort(); /* ok */
 392                 }
 393 #endif
 394
 395         CRYPTO_free_ex_data(ssl_session_meth,(char *)ss,&ss->ex_data);
 396
 397         memset(ss->key_arg,0,SSL_MAX_KEY_ARG_LENGTH);
 398         memset(ss->master_key,0,SSL_MAX_MASTER_KEY_LENGTH);
 399         memset(ss->session_id,0,SSL_MAX_SSL_SESSION_ID_LENGTH);
 400         if (ss->cert != NULL) ssl_cert_free(ss->cert);
 401         if (ss->peer != NULL) X509_free(ss->peer);
 402         if (ss->ciphers != NULL) sk_free(ss->ciphers);
 403         memset(ss,0,sizeof(*ss));
 404         Free(ss);
 405         }
 406
 407 int SSL_set_session(s, session)
 408 SSL *s;
 409 SSL_SESSION *session;
 410         {
 411         int ret=0;
 412         SSL_METHOD *meth;
 413
 414         if (session != NULL)
 415                 {
 416                 meth=s->ctx->method->get_ssl_method(session->ssl_version);
 417                 if (meth == NULL)
 418                         meth=s->method->get_ssl_method(session->ssl_version);
 419                 if (meth == NULL)
 420                         {
 421                         SSLerr(SSL_F_SSL_SET_SESSION,SSL_R_UNABLE_TO_FIND_SSL_METHOD);
 422                         return(0);
 423                         }
 424
 425                 if (meth != s->method)
 426                         {
 427                         if (!SSL_set_ssl_method(s,meth))
 428                                 return(0);
 429                         if (s->ctx->session_timeout == 0)
 430                                 session->timeout=SSL_get_default_timeout(s);
 431                         else
 432                                 session->timeout=s->ctx->session_timeout;
 433                         }
 434
 435                 /* CRYPTO_w_lock(CRYPTO_LOCK_SSL);*/
 436                 CRYPTO_add(&session->references,1,CRYPTO_LOCK_SSL_SESSION);
 437                 if (s->session != NULL)
 438                         SSL_SESSION_free(s->session);
 439                 s->session=session;
 440                 /* CRYPTO_w_unlock(CRYPTO_LOCK_SSL);*/
 441                 ret=1;
 442                 }
 443         else
 444                 {
 445                 if (s->session != NULL)
 446                         {
 447                         SSL_SESSION_free(s->session);
 448                         s->session=NULL;
 449                         }
 450
 451                 meth=s->ctx->method;
 452                 if (meth != s->method)
 453                         {
 454                         if (!SSL_set_ssl_method(s,meth))
 455                                 return(0);
 456                         }
 457                 ret=1;
 458                 }
 459         return(ret);
 460         }
 461
 462 long SSL_SESSION_set_timeout(s,t)
 463 SSL_SESSION *s;
 464 long t;
 465         {
 466         if (s == NULL) return(0);
 467         s->timeout=t;
 468         return(1);
 469         }
 470
 471 long SSL_SESSION_get_timeout(s)
 472 SSL_SESSION *s;
 473         {
 474         if (s == NULL) return(0);
 475         return(s->timeout);
 476         }
 477
 478 long SSL_SESSION_get_time(s)
 479 SSL_SESSION *s;
 480         {
 481         if (s == NULL) return(0);
 482         return(s->time);
 483         }
 484
 485 long SSL_SESSION_set_time(s,t)
 486 SSL_SESSION *s;
 487 long t;
 488         {
 489         if (s == NULL) return(0);
 490         s->time=t;
 491         return(t);
 492         }
 493
 494 long SSL_CTX_set_timeout(s,t)
 495 SSL_CTX *s;
 496 long t;
 497         {
 498         long l;
 499         if (s == NULL) return(0);
 500         l=s->session_timeout;
 501         s->session_timeout=t;
 502         return(l);
 503         }
 504
 505 long SSL_CTX_get_timeout(s)
 506 SSL_CTX *s;
 507         {
 508         if (s == NULL) return(0);
 509         return(s->session_timeout);
 510         }
 511
 512 typedef struct timeout_param_st
 513         {
 514         SSL_CTX *ctx;
 515         long time;
 516         LHASH *cache;
 517         } TIMEOUT_PARAM;
 518
 519 static void timeout(s,p)
 520 SSL_SESSION *s;
 521 TIMEOUT_PARAM *p;
 522         {
 523         if ((p->time == 0) || (p->time > (s->time+s->timeout))) /* timeout */
 524                 {
 525                 /* The reason we don't call SSL_CTX_remove_session() is to
 526                  * save on locking overhead */
 527                 lh_delete(p->cache,(char *)s);
 528                 SSL_SESSION_list_remove(p->ctx,s);
 529                 s->not_resumable=1;
 530                 if (p->ctx->remove_session_cb != NULL)
 531                         p->ctx->remove_session_cb(p->ctx,s);
 532                 SSL_SESSION_free(s);
 533                 }
 534         }
 535
 536 void SSL_CTX_flush_sessions(s,t)
 537 SSL_CTX *s;
 538 long t;
 539         {
 540         unsigned long i;
 541         TIMEOUT_PARAM tp;
 542
 543         tp.ctx=s;
 544         tp.cache=s->sessions;
 545         if (tp.cache == NULL) return;
 546         tp.time=t;
 547         CRYPTO_w_lock(CRYPTO_LOCK_SSL_CTX);
 548         i=tp.cache->down_load;
 549         tp.cache->down_load=0;
 550         lh_doall_arg(tp.cache,(void (*)())timeout,(char *)&tp);
 551         tp.cache->down_load=i;
 552         CRYPTO_w_unlock(CRYPTO_LOCK_SSL_CTX);
 553         }
 554
 555 int ssl_clear_bad_session(s)
 556 SSL *s;
 557         {
 558         if (    (s->session != NULL) &&
 559                 !(s->shutdown & SSL_SENT_SHUTDOWN) &&
 560                 !(SSL_in_init(s) || SSL_in_before(s)))
 561                 {
 562                 SSL_CTX_remove_session(s->ctx,s->session);
 563                 return(1);
 564                 }
 565         else
 566                 return(0);
 567         }
 568
 569 /* locked by SSL_CTX in the calling function */
 570 static void SSL_SESSION_list_remove(ctx,s)
 571 SSL_CTX *ctx;
 572 SSL_SESSION *s;
 573         {
 574         if ((s->next == NULL) || (s->prev == NULL)) return;
 575
 576         if (s->next == (SSL_SESSION *)&(ctx->session_cache_tail))
 577                 { /* last element in list */
 578                 if (s->prev == (SSL_SESSION *)&(ctx->session_cache_head))
 579                         { /* only one element in list */
 580                         ctx->session_cache_head=NULL;
 581                         ctx->session_cache_tail=NULL;
 582                         }
 583                 else
 584                         {
 585                         ctx->session_cache_tail=s->prev;
 586                         s->prev->next=(SSL_SESSION *)&(ctx->session_cache_tail);
 587                         }
 588                 }
 589         else
 590                 {
 591                 if (s->prev == (SSL_SESSION *)&(ctx->session_cache_head))
 592                         { /* first element in list */
 593                         ctx->session_cache_head=s->next;
 594                         s->next->prev=(SSL_SESSION *)&(ctx->session_cache_head);
 595                         }
 596                 else
 597                         { /* middle of list */
 598                         s->next->prev=s->prev;
 599                         s->prev->next=s->next;
 600                         }
 601                 }
 602         s->prev=s->next=NULL;
 603         }
 604
 605 static void SSL_SESSION_list_add(ctx,s)
 606 SSL_CTX *ctx;
 607 SSL_SESSION *s;
 608         {
 609         if ((s->next != NULL) && (s->prev != NULL))
 610                 SSL_SESSION_list_remove(ctx,s);
 611
 612         if (ctx->session_cache_head == NULL)
 613                 {
 614                 ctx->session_cache_head=s;
 615                 ctx->session_cache_tail=s;
 616                 s->prev=(SSL_SESSION *)&(ctx->session_cache_head);
 617                 s->next=(SSL_SESSION *)&(ctx->session_cache_tail);
 618                 }
 619         else
 620                 {
 621                 s->next=ctx->session_cache_head;
 622                 s->next->prev=s;
 623                 s->prev=(SSL_SESSION *)&(ctx->session_cache_head);
 624                 ctx->session_cache_head=s;
 625                 }
 626         }
 627