ssl/ssl_sess.c

   1 /* ssl/ssl_sess.c */
   2 /* Copyright (C) 1995-1997 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 SSL_SESSION *SSL_SESSION_new()
  65         {
  66         SSL_SESSION *ss;
  67
  68         ss=(SSL_SESSION *)Malloc(sizeof(SSL_SESSION));
  69         if (ss == NULL)
  70                 {
  71                 SSLerr(SSL_F_SSL_SESSION_NEW,ERR_R_MALLOC_FAILURE);
  72                 return(0);
  73                 }
  74         memset(ss,0,sizeof(SSL_SESSION));
  75
  76         ss->references=1;
  77         ss->timeout=60*5+4; /* 5 minute timeout by default */
  78         ss->time=time(NULL);
  79         return(ss);
  80         }
  81
  82 int ssl_get_new_session(s, session)
  83 SSL *s;
  84 int session;
  85         {
  86         SSL_SESSION *ss=NULL;
  87
  88         if ((ss=SSL_SESSION_new()) == NULL) return(0);
  89
  90         /* If the context has a default timeout, use it */
  91         if (s->ctx->session_timeout != 0)
  92                 ss->timeout=SSL_get_default_timeout(s);
  93
  94         if (s->session != NULL)
  95                 {
  96                 SSL_SESSION_free(s->session);
  97                 s->session=NULL;
  98                 }
  99
 100         if (session)
 101                 {
 102                 if (s->version == SSL2_CLIENT_VERSION)
 103                         {
 104                         ss->ssl_version=2;
 105                         ss->session_id_length=SSL2_SSL_SESSION_ID_LENGTH;
 106                         }
 107                 else if (s->version == SSL3_VERSION_MAJOR)
 108                         {
 109                         ss->ssl_version=3;
 110                         ss->session_id_length=SSL3_SSL_SESSION_ID_LENGTH;
 111                         }
 112                 else
 113                         {
 114                         SSLerr(SSL_F_SSL_GET_NEW_SESSION,SSL_R_UNSUPPORTED_SSL_VERSION);
 115                         SSL_SESSION_free(ss);
 116                         return(0);
 117                         }
 118
 119                 for (;;)
 120                         {
 121                         SSL_SESSION *r;
 122
 123                         RAND_bytes(ss->session_id,ss->session_id_length);
 124                         CRYPTO_r_lock(CRYPTO_LOCK_SSL_CTX);
 125                         r=(SSL_SESSION *)lh_retrieve(s->ctx->sessions,
 126                                 (char *)ss);
 127                         CRYPTO_r_unlock(CRYPTO_LOCK_SSL_CTX);
 128                         if (r == NULL) break;
 129                         /* else - woops a session_id match */
 130                         }
 131                 }
 132         else
 133                 {
 134                 ss->session_id_length=0;
 135                 }
 136
 137         s->session=ss;
 138         ss->ssl_version=s->version;
 139
 140         return(1);
 141         }
 142
 143 int ssl_get_prev_session(s, len, session)
 144 SSL *s;
 145 int len;
 146 unsigned char *session;
 147         {
 148         SSL_SESSION *ret,data;
 149
 150         /* conn_init();*/
 151         data.ssl_version=s->version;
 152         data.session_id_length=len;
 153         if (len > SSL_MAX_SSL_SESSION_ID_LENGTH)
 154                 return(0);
 155         memcpy(data.session_id,session,len);;
 156
 157         CRYPTO_r_lock(CRYPTO_LOCK_SSL_CTX);
 158         ret=(SSL_SESSION *)lh_retrieve(s->ctx->sessions,(char *)&data);
 159         CRYPTO_r_unlock(CRYPTO_LOCK_SSL_CTX);
 160
 161         if (ret == NULL)
 162                 {
 163                 int copy=1;
 164
 165                 s->ctx->sess_miss++;
 166                 ret=NULL;
 167                 if ((s->ctx->get_session_cb != NULL) &&
 168                         ((ret=s->ctx->get_session_cb(s,session,len,&copy))
 169                                 != NULL))
 170                         {
 171                         s->ctx->sess_cb_hit++;
 172
 173                         /* The following should not return 1, otherwise,
 174                          * things are very strange */
 175                         SSL_CTX_add_session(s->ctx,ret);
 176                         /* auto free it */
 177                         if (!copy)
 178                                 SSL_SESSION_free(ret);
 179                         }
 180                 if (ret == NULL) return(0);
 181                 }
 182
 183         if (ret->cipher == NULL)
 184                 {
 185                 char buf[5],*p;
 186                 unsigned long l;
 187
 188                 p=buf;
 189                 l=ret->cipher_id;
 190                 l2n(l,p);
 191                 if (ret->ssl_version == 3)
 192                         ret->cipher=ssl_get_cipher_by_char(s,&(buf[2]));
 193                 else
 194                         ret->cipher=ssl_get_cipher_by_char(s,&(buf[1]));
 195                 if (ret->cipher == NULL)
 196                         return(0);
 197                 }
 198
 199         /* If a thread got the session, then 'swaped', and another got
 200          * it and then due to a time-out decided to 'Free' it we could
 201          * be in trouble.  So I'll increment it now, then double decrement
 202          * later - am I speaking rubbish?. */
 203         CRYPTO_add(&ret->references,1,CRYPTO_LOCK_SSL_SESSION);
 204
 205         if ((long)(ret->time+ret->timeout) < (long)time(NULL)) /* timeout */
 206                 {
 207                 s->ctx->sess_timeout++;
 208                 /* remove it from the cache */
 209                 SSL_CTX_remove_session(s->ctx,ret);
 210                 SSL_SESSION_free(ret);          /* again to actually Free it */
 211                 return(0);
 212                 }
 213
 214         s->ctx->sess_hit++;
 215
 216         /* ret->time=time(NULL); */ /* rezero timeout? */
 217         /* again, just leave the session
 218          * if it is the same session, we have just incremented and
 219          * then decremented the reference count :-) */
 220         if (s->session != NULL)
 221                 SSL_SESSION_free(s->session);
 222         s->session=ret;
 223         return(1);
 224         }
 225
 226 int SSL_CTX_add_session(ctx,c)
 227 SSL_CTX *ctx;
 228 SSL_SESSION *c;
 229         {
 230         SSL_SESSION *s;
 231
 232         /* conn_init(); */
 233         CRYPTO_add(&c->references,1,CRYPTO_LOCK_SSL_SESSION);
 234
 235         CRYPTO_w_lock(CRYPTO_LOCK_SSL_CTX);
 236         s=(SSL_SESSION *)lh_insert(ctx->sessions,(char *)c);
 237         CRYPTO_w_unlock(CRYPTO_LOCK_SSL_CTX);
 238
 239         /* If the same session if is being 're-added', Free the old
 240          * one when the last person stops using it.
 241          * This will also work if it is alread in the cache.
 242          * The references will go up and then down :-) */
 243         if (s != NULL)
 244                 {
 245                 SSL_SESSION_free(s);
 246                 return(0);
 247                 }
 248         else
 249                 return(1);
 250         }
 251
 252 int SSL_CTX_remove_session(ctx,c)
 253 SSL_CTX *ctx;
 254 SSL_SESSION *c;
 255         {
 256         SSL_SESSION *r;
 257         int ret=0;
 258
 259         if ((c->session_id_length != 0) && (c != NULL))
 260                 {
 261                 CRYPTO_w_lock(CRYPTO_LOCK_SSL_CTX);
 262                 r=(SSL_SESSION *)lh_delete(ctx->sessions,(char *)c);
 263                 if (r != NULL) ret=1;
 264
 265                 CRYPTO_w_unlock(CRYPTO_LOCK_SSL_CTX);
 266
 267                 if (ret)
 268                         {
 269                         r->not_resumable=1;
 270                         if (ctx->remove_session_cb != NULL)
 271                                 ctx->remove_session_cb(ctx,c);
 272                         SSL_SESSION_free(r);
 273                         }
 274                 }
 275         else
 276                 ret=0;
 277         return(ret);
 278         }
 279
 280 void SSL_SESSION_free(ss)
 281 SSL_SESSION *ss;
 282         {
 283         int i;
 284
 285         i=CRYPTO_add(&ss->references,-1,CRYPTO_LOCK_SSL_SESSION);
 286         if (i > 0) return;
 287 #ifdef REF_CHECK
 288         if (i < 0)
 289                 {
 290                 fprintf(stderr,"SSL_SESSION_free, bad reference count\n");
 291                 abort(); /* ok */
 292                 }
 293 #endif
 294
 295         memset(ss->key_arg,0,SSL_MAX_KEY_ARG_LENGTH);
 296         memset(ss->master_key,0,SSL_MAX_MASTER_KEY_LENGTH);
 297         memset(ss->session_id,0,SSL_MAX_SSL_SESSION_ID_LENGTH);
 298         if (ss->cert != NULL) ssl_cert_free(ss->cert);
 299         if (ss->peer != NULL) X509_free(ss->peer);
 300         if (ss->ciphers != NULL) sk_free(ss->ciphers);
 301         memset(ss,0,sizeof(*ss));
 302         Free(ss);
 303         }
 304
 305 int SSL_set_session(s, session)
 306 SSL *s;
 307 SSL_SESSION *session;
 308         {
 309         int ret=0;
 310         SSL_METHOD *meth;
 311
 312         if (session != NULL)
 313                 {
 314                 meth=s->ctx->method->get_ssl_method(session->ssl_version);
 315                 if (meth == NULL)
 316                         meth=s->method->get_ssl_method(session->ssl_version);
 317                 if (meth == NULL)
 318                         {
 319                         SSLerr(SSL_F_SSL_SET_SESSION,SSL_R_UNABLE_TO_FIND_SSL_METHOD);
 320                         return(0);
 321                         }
 322
 323                 if (meth != s->method)
 324                         {
 325                         if (!SSL_set_ssl_method(s,meth))
 326                                 return(0);
 327                         session->timeout=SSL_get_default_timeout(s);
 328                         }
 329
 330                 /* CRYPTO_w_lock(CRYPTO_LOCK_SSL);*/
 331                 CRYPTO_add(&session->references,1,CRYPTO_LOCK_SSL_SESSION);
 332                 if (s->session != NULL)
 333                         SSL_SESSION_free(s->session);
 334                 s->session=session;
 335                 /* CRYPTO_w_unlock(CRYPTO_LOCK_SSL);*/
 336                 ret=1;
 337                 }
 338         return(ret);
 339         }
 340
 341 long SSL_set_timeout(s,t)
 342 SSL_SESSION *s;
 343 long t;
 344         {
 345         if (s == NULL) return(0);
 346         s->timeout=t;
 347         return(1);
 348         }
 349
 350 long SSL_get_timeout(s)
 351 SSL_SESSION *s;
 352         {
 353         if (s == NULL) return(0);
 354         return(s->timeout);
 355         }
 356
 357 long SSL_get_time(s)
 358 SSL_SESSION *s;
 359         {
 360         if (s == NULL) return(0);
 361         return(s->time);
 362         }
 363
 364 long SSL_set_time(s,t)
 365 SSL_SESSION *s;
 366 long t;
 367         {
 368         if (s == NULL) return(0);
 369         s->time=t;
 370         return(t);
 371         }
 372
 373 typedef struct timeout_param_st
 374         {
 375         SSL_CTX *ctx;
 376         long time;
 377         LHASH *cache;
 378         } TIMEOUT_PARAM;
 379
 380 static void timeout(s,p)
 381 SSL_SESSION *s;
 382 TIMEOUT_PARAM *p;
 383         {
 384         if ((p->time == 0) || (p->time > (s->time+s->timeout))) /* timeout */
 385                 {
 386                 lh_delete(p->cache,(char *)s);
 387                 s->not_resumable=1;
 388                 if (p->ctx->remove_session_cb != NULL)
 389                         p->ctx->remove_session_cb(p->ctx,s);
 390                 SSL_SESSION_free(s);
 391                 }
 392         }
 393
 394 void SSL_CTX_flush_sessions(s,t)
 395 SSL_CTX *s;
 396 long t;
 397         {
 398         unsigned long i;
 399         TIMEOUT_PARAM tp;
 400
 401         tp.ctx=s;
 402         tp.cache=SSL_CTX_sessions(s);
 403         if (tp.cache == NULL) return;
 404         tp.time=t;
 405         CRYPTO_w_lock(CRYPTO_LOCK_SSL_CTX);
 406         i=tp.cache->down_load;
 407         tp.cache->down_load=0;
 408         lh_doall_arg(tp.cache,(void (*)())timeout,(char *)&tp);
 409         tp.cache->down_load=i;
 410         CRYPTO_w_unlock(CRYPTO_LOCK_SSL_CTX);
 411         }
 412
 413 int ssl_clear_bad_session(s)
 414 SSL *s;
 415         {
 416         if (    (s->session != NULL) &&
 417                 !(s->shutdown & SSL_SENT_SHUTDOWN) &&
 418                 !(SSL_in_init(s) || SSL_in_before(s)))
 419                 {
 420                 SSL_CTX_remove_session(s->ctx,s->session);
 421                 return(1);
 422                 }
 423         else
 424                 return(0);
 425         }