crypto/openssl-0.9.7d/crypto/ex_data.c

   1 /* crypto/ex_data.c */
   2
   3 /*
   4  * Overhaul notes;
   5  *
   6  * This code is now *mostly* thread-safe. It is now easier to understand in what
   7  * ways it is safe and in what ways it is not, which is an improvement. Firstly,
   8  * all per-class stacks and index-counters for ex_data are stored in the same
   9  * global LHASH table (keyed by class). This hash table uses locking for all
  10  * access with the exception of CRYPTO_cleanup_all_ex_data(), which must only be
  11  * called when no other threads can possibly race against it (even if it was
  12  * locked, the race would mean it's possible the hash table might have been
  13  * recreated after the cleanup). As classes can only be added to the hash table,
  14  * and within each class, the stack of methods can only be incremented, the
  15  * locking mechanics are simpler than they would otherwise be. For example, the
  16  * new/dup/free ex_data functions will lock the hash table, copy the method
  17  * pointers it needs from the relevant class, then unlock the hash table before
  18  * actually applying those method pointers to the task of the new/dup/free
  19  * operations. As they can't be removed from the method-stack, only
  20  * supplemented, there's no race conditions associated with using them outside
  21  * the lock. The get/set_ex_data functions are not locked because they do not
  22  * involve this global state at all - they operate directly with a previously
  23  * obtained per-class method index and a particular "ex_data" variable. These
  24  * variables are usually instantiated per-context (eg. each RSA structure has
  25  * one) so locking on read/write access to that variable can be locked locally
  26  * if required (eg. using the "RSA" lock to synchronise access to a
  27  * per-RSA-structure ex_data variable if required).
  28  * [Geoff]
  29  */
  30
  31 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  32  * All rights reserved.
  33  *
  34  * This package is an SSL implementation written
  35  * by Eric Young (eay@cryptsoft.com).
  36  * The implementation was written so as to conform with Netscapes SSL.
  37  *
  38  * This library is free for commercial and non-commercial use as long as
  39  * the following conditions are aheared to.  The following conditions
  40  * apply to all code found in this distribution, be it the RC4, RSA,
  41  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
  42  * included with this distribution is covered by the same copyright terms
  43  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
  44  *
  45  * Copyright remains Eric Young's, and as such any Copyright notices in
  46  * the code are not to be removed.
  47  * If this package is used in a product, Eric Young should be given attribution
  48  * as the author of the parts of the library used.
  49  * This can be in the form of a textual message at program startup or
  50  * in documentation (online or textual) provided with the package.
  51  *
  52  * Redistribution and use in source and binary forms, with or without
  53  * modification, are permitted provided that the following conditions
  54  * are met:
  55  * 1. Redistributions of source code must retain the copyright
  56  *    notice, this list of conditions and the following disclaimer.
  57  * 2. Redistributions in binary form must reproduce the above copyright
  58  *    notice, this list of conditions and the following disclaimer in the
  59  *    documentation and/or other materials provided with the distribution.
  60  * 3. All advertising materials mentioning features or use of this software
  61  *    must display the following acknowledgement:
  62  *    "This product includes cryptographic software written by
  63  *     Eric Young (eay@cryptsoft.com)"
  64  *    The word 'cryptographic' can be left out if the rouines from the library
  65  *    being used are not cryptographic related :-).
  66  * 4. If you include any Windows specific code (or a derivative thereof) from
  67  *    the apps directory (application code) you must include an acknowledgement:
  68  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
  69  *
  70  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
  71  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  72  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  73  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  74  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  75  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  76  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  77  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  78  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  79  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  80  * SUCH DAMAGE.
  81  *
  82  * The licence and distribution terms for any publically available version or
  83  * derivative of this code cannot be changed.  i.e. this code cannot simply be
  84  * copied and put under another distribution licence
  85  * [including the GNU Public Licence.]
  86  */
  87 /* ====================================================================
  88  * Copyright (c) 1998-2001 The OpenSSL Project.  All rights reserved.
  89  *
  90  * Redistribution and use in source and binary forms, with or without
  91  * modification, are permitted provided that the following conditions
  92  * are met:
  93  *
  94  * 1. Redistributions of source code must retain the above copyright
  95  *    notice, this list of conditions and the following disclaimer.
  96  *
  97  * 2. Redistributions in binary form must reproduce the above copyright
  98  *    notice, this list of conditions and the following disclaimer in
  99  *    the documentation and/or other materials provided with the
 100  *    distribution.
 101  *
 102  * 3. All advertising materials mentioning features or use of this
 103  *    software must display the following acknowledgment:
 104  *    "This product includes software developed by the OpenSSL Project
 105  *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
 106  *
 107  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
 108  *    endorse or promote products derived from this software without
 109  *    prior written permission. For written permission, please contact
 110  *    openssl-core@openssl.org.
 111  *
 112  * 5. Products derived from this software may not be called "OpenSSL"
 113  *    nor may "OpenSSL" appear in their names without prior written
 114  *    permission of the OpenSSL Project.
 115  *
 116  * 6. Redistributions of any form whatsoever must retain the following
 117  *    acknowledgment:
 118  *    "This product includes software developed by the OpenSSL Project
 119  *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
 120  *
 121  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
 122  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 123  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 124  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
 125  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 126  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 127  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 128  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 129  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 130  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 131  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 132  * OF THE POSSIBILITY OF SUCH DAMAGE.
 133  * ====================================================================
 134  *
 135  * This product includes cryptographic software written by Eric Young
 136  * (eay@cryptsoft.com).  This product includes software written by Tim
 137  * Hudson (tjh@cryptsoft.com).
 138  *
 139  */
 140
 141 #include <stdio.h>
 142 #include <stdlib.h>
 143 #include <openssl/buffer.h>
 144 #include <openssl/bio.h>
 145 #include <openssl/lhash.h>
 146 #include "cryptlib.h"
 147
 148 /* What an "implementation of ex_data functionality" looks like */
 149 struct st_CRYPTO_EX_DATA_IMPL
 150         {
 151         /*********************/
 152         /* GLOBAL OPERATIONS */
 153         /* Return a new class index */
 154         int (*cb_new_class)(void);
 155         /* Cleanup all state used by the implementation */
 156         void (*cb_cleanup)(void);
 157         /************************/
 158         /* PER-CLASS OPERATIONS */
 159         /* Get a new method index within a class */
 160         int (*cb_get_new_index)(int class_index, long argl, void *argp,
 161                         CRYPTO_EX_new *new_func, CRYPTO_EX_dup *dup_func,
 162                         CRYPTO_EX_free *free_func);
 163         /* Initialise a new CRYPTO_EX_DATA of a given class */
 164         int (*cb_new_ex_data)(int class_index, void *obj,
 165                         CRYPTO_EX_DATA *ad);
 166         /* Duplicate a CRYPTO_EX_DATA of a given class onto a copy */
 167         int (*cb_dup_ex_data)(int class_index, CRYPTO_EX_DATA *to,
 168                         CRYPTO_EX_DATA *from);
 169         /* Cleanup a CRYPTO_EX_DATA of a given class */
 170         void (*cb_free_ex_data)(int class_index, void *obj,
 171                         CRYPTO_EX_DATA *ad);
 172         };
 173
 174 /* The implementation we use at run-time */
 175 static const CRYPTO_EX_DATA_IMPL *impl = NULL;
 176
 177 /* To call "impl" functions, use this macro rather than referring to 'impl' directly, eg.
 178  * EX_IMPL(get_new_index)(...); */
 179 #define EX_IMPL(a) impl->cb_##a
 180
 181 /* Predeclare the "default" ex_data implementation */
 182 static int int_new_class(void);
 183 static void int_cleanup(void);
 184 static int int_get_new_index(int class_index, long argl, void *argp,
 185                 CRYPTO_EX_new *new_func, CRYPTO_EX_dup *dup_func,
 186                 CRYPTO_EX_free *free_func);
 187 static int int_new_ex_data(int class_index, void *obj,
 188                 CRYPTO_EX_DATA *ad);
 189 static int int_dup_ex_data(int class_index, CRYPTO_EX_DATA *to,
 190                 CRYPTO_EX_DATA *from);
 191 static void int_free_ex_data(int class_index, void *obj,
 192                 CRYPTO_EX_DATA *ad);
 193 static CRYPTO_EX_DATA_IMPL impl_default =
 194         {
 195         int_new_class,
 196         int_cleanup,
 197         int_get_new_index,
 198         int_new_ex_data,
 199         int_dup_ex_data,
 200         int_free_ex_data
 201         };
 202
 203 /* Internal function that checks whether "impl" is set and if not, sets it to
 204  * the default. */
 205 static void impl_check(void)
 206         {
 207         CRYPTO_w_lock(CRYPTO_LOCK_EX_DATA);
 208         if(!impl)
 209                 impl = &impl_default;
 210         CRYPTO_w_unlock(CRYPTO_LOCK_EX_DATA);
 211         }
 212 /* A macro wrapper for impl_check that first uses a non-locked test before
 213  * invoking the function (which checks again inside a lock). */
 214 #define IMPL_CHECK if(!impl) impl_check();
 215
 216 /* API functions to get/set the "ex_data" implementation */
 217 const CRYPTO_EX_DATA_IMPL *CRYPTO_get_ex_data_implementation(void)
 218         {
 219         IMPL_CHECK
 220         return impl;
 221         }
 222 int CRYPTO_set_ex_data_implementation(const CRYPTO_EX_DATA_IMPL *i)
 223         {
 224         int toret = 0;
 225         CRYPTO_w_lock(CRYPTO_LOCK_EX_DATA);
 226         if(!impl)
 227                 {
 228                 impl = i;
 229                 toret = 1;
 230                 }
 231         CRYPTO_w_unlock(CRYPTO_LOCK_EX_DATA);
 232         return toret;
 233         }
 234
 235 /****************************************************************************/
 236 /* Interal (default) implementation of "ex_data" support. API functions are
 237  * further down. */
 238
 239 /* The type that represents what each "class" used to implement locally. A STACK
 240  * of CRYPTO_EX_DATA_FUNCS plus a index-counter. The 'class_index' is the global
 241  * value representing the class that is used to distinguish these items. */
 242 typedef struct st_ex_class_item {
 243         int class_index;
 244         STACK_OF(CRYPTO_EX_DATA_FUNCS) *meth;
 245         int meth_num;
 246 } EX_CLASS_ITEM;
 247
 248 /* When assigning new class indexes, this is our counter */
 249 static int ex_class = CRYPTO_EX_INDEX_USER;
 250
 251 /* The global hash table of EX_CLASS_ITEM items */
 252 static LHASH *ex_data = NULL;
 253
 254 /* The callbacks required in the "ex_data" hash table */
 255 static unsigned long ex_hash_cb(const void *a_void)
 256         {
 257         return ((const EX_CLASS_ITEM *)a_void)->class_index;
 258         }
 259 static int ex_cmp_cb(const void *a_void, const void *b_void)
 260         {
 261         return (((const EX_CLASS_ITEM *)a_void)->class_index -
 262                 ((const EX_CLASS_ITEM *)b_void)->class_index);
 263         }
 264
 265 /* Internal functions used by the "impl_default" implementation to access the
 266  * state */
 267
 268 static int ex_data_check(void)
 269         {
 270         int toret = 1;
 271         CRYPTO_w_lock(CRYPTO_LOCK_EX_DATA);
 272         if(!ex_data && ((ex_data = lh_new(ex_hash_cb, ex_cmp_cb)) == NULL))
 273                 toret = 0;
 274         CRYPTO_w_unlock(CRYPTO_LOCK_EX_DATA);
 275         return toret;
 276         }
 277 /* This macros helps reduce the locking from repeated checks because the
 278  * ex_data_check() function checks ex_data again inside a lock. */
 279 #define EX_DATA_CHECK(iffail) if(!ex_data && !ex_data_check()) {iffail}
 280
 281 /* This "inner" callback is used by the callback function that follows it */
 282 static void def_cleanup_util_cb(CRYPTO_EX_DATA_FUNCS *funcs)
 283         {
 284         OPENSSL_free(funcs);
 285         }
 286
 287 /* This callback is used in lh_doall to destroy all EX_CLASS_ITEM values from
 288  * "ex_data" prior to the ex_data hash table being itself destroyed. Doesn't do
 289  * any locking. */
 290 static void def_cleanup_cb(const void *a_void)
 291         {
 292         EX_CLASS_ITEM *item = (EX_CLASS_ITEM *)a_void;
 293         sk_CRYPTO_EX_DATA_FUNCS_pop_free(item->meth, def_cleanup_util_cb);
 294         OPENSSL_free(item);
 295         }
 296
 297 /* Return the EX_CLASS_ITEM from the "ex_data" hash table that corresponds to a
 298  * given class. Handles locking. */
 299 static EX_CLASS_ITEM *def_get_class(int class_index)
 300         {
 301         EX_CLASS_ITEM d, *p, *gen;
 302         EX_DATA_CHECK(return NULL;)
 303         d.class_index = class_index;
 304         CRYPTO_w_lock(CRYPTO_LOCK_EX_DATA);
 305         p = lh_retrieve(ex_data, &d);
 306         if(!p)
 307                 {
 308                 gen = OPENSSL_malloc(sizeof(EX_CLASS_ITEM));
 309                 if(gen)
 310                         {
 311                         gen->class_index = class_index;
 312                         gen->meth_num = 0;
 313                         gen->meth = sk_CRYPTO_EX_DATA_FUNCS_new_null();
 314                         if(!gen->meth)
 315                                 OPENSSL_free(gen);
 316                         else
 317                                 {
 318                                 /* Because we're inside the ex_data lock, the
 319                                  * return value from the insert will be NULL */
 320                                 lh_insert(ex_data, gen);
 321                                 p = gen;
 322                                 }
 323                         }
 324                 }
 325         CRYPTO_w_unlock(CRYPTO_LOCK_EX_DATA);
 326         if(!p)
 327                 CRYPTOerr(CRYPTO_F_DEF_GET_CLASS,ERR_R_MALLOC_FAILURE);
 328         return p;
 329         }
 330
 331 /* Add a new method to the given EX_CLASS_ITEM and return the corresponding
 332  * index (or -1 for error). Handles locking. */
 333 static int def_add_index(EX_CLASS_ITEM *item, long argl, void *argp,
 334                 CRYPTO_EX_new *new_func, CRYPTO_EX_dup *dup_func,
 335                 CRYPTO_EX_free *free_func)
 336         {
 337         int toret = -1;
 338         CRYPTO_EX_DATA_FUNCS *a = (CRYPTO_EX_DATA_FUNCS *)OPENSSL_malloc(
 339                                         sizeof(CRYPTO_EX_DATA_FUNCS));
 340         if(!a)
 341                 {
 342                 CRYPTOerr(CRYPTO_F_DEF_ADD_INDEX,ERR_R_MALLOC_FAILURE);
 343                 return -1;
 344                 }
 345         a->argl=argl;
 346         a->argp=argp;
 347         a->new_func=new_func;
 348         a->dup_func=dup_func;
 349         a->free_func=free_func;
 350         CRYPTO_w_lock(CRYPTO_LOCK_EX_DATA);
 351         while (sk_CRYPTO_EX_DATA_FUNCS_num(item->meth) <= item->meth_num)
 352                 {
 353                 if (!sk_CRYPTO_EX_DATA_FUNCS_push(item->meth, NULL))
 354                         {
 355                         CRYPTOerr(CRYPTO_F_DEF_ADD_INDEX,ERR_R_MALLOC_FAILURE);
 356                         OPENSSL_free(a);
 357                         goto err;
 358                         }
 359                 }
 360         toret = item->meth_num++;
 361         sk_CRYPTO_EX_DATA_FUNCS_set(item->meth, toret, a);
 362 err:
 363         CRYPTO_w_unlock(CRYPTO_LOCK_EX_DATA);
 364         return toret;
 365         }
 366
 367 /**************************************************************/
 368 /* The functions in the default CRYPTO_EX_DATA_IMPL structure */
 369
 370 static int int_new_class(void)
 371         {
 372         int toret;
 373         CRYPTO_w_lock(CRYPTO_LOCK_EX_DATA);
 374         toret = ex_class++;
 375         CRYPTO_w_unlock(CRYPTO_LOCK_EX_DATA);
 376         return toret;
 377         }
 378
 379 static void int_cleanup(void)
 380         {
 381         EX_DATA_CHECK(return;)
 382         lh_doall(ex_data, def_cleanup_cb);
 383         lh_free(ex_data);
 384         ex_data = NULL;
 385         impl = NULL;
 386         }
 387
 388 static int int_get_new_index(int class_index, long argl, void *argp,
 389                 CRYPTO_EX_new *new_func, CRYPTO_EX_dup *dup_func,
 390                 CRYPTO_EX_free *free_func)
 391         {
 392         EX_CLASS_ITEM *item = def_get_class(class_index);
 393         if(!item)
 394                 return -1;
 395         return def_add_index(item, argl, argp, new_func, dup_func, free_func);
 396         }
 397
 398 /* Thread-safe by copying a class's array of "CRYPTO_EX_DATA_FUNCS" entries in
 399  * the lock, then using them outside the lock. NB: Thread-safety only applies to
 400  * the global "ex_data" state (ie. class definitions), not thread-safe on 'ad'
 401  * itself. */
 402 static int int_new_ex_data(int class_index, void *obj,
 403                 CRYPTO_EX_DATA *ad)
 404         {
 405         int mx,i;
 406         void *ptr;
 407         CRYPTO_EX_DATA_FUNCS **storage = NULL;
 408         EX_CLASS_ITEM *item = def_get_class(class_index);
 409         if(!item)
 410                 /* error is already set */
 411                 return 0;
 412         ad->sk = NULL;
 413         CRYPTO_r_lock(CRYPTO_LOCK_EX_DATA);
 414         mx = sk_CRYPTO_EX_DATA_FUNCS_num(item->meth);
 415         if(mx > 0)
 416                 {
 417                 storage = OPENSSL_malloc(mx * sizeof(CRYPTO_EX_DATA_FUNCS*));
 418                 if(!storage)
 419                         goto skip;
 420                 for(i = 0; i < mx; i++)
 421                         storage[i] = sk_CRYPTO_EX_DATA_FUNCS_value(item->meth,i);
 422                 }
 423 skip:
 424         CRYPTO_r_unlock(CRYPTO_LOCK_EX_DATA);
 425         if((mx > 0) && !storage)
 426                 {
 427                 CRYPTOerr(CRYPTO_F_INT_NEW_EX_DATA,ERR_R_MALLOC_FAILURE);
 428                 return 0;
 429                 }
 430         for(i = 0; i < mx; i++)
 431                 {
 432                 if(storage[i] && storage[i]->new_func)
 433                         {
 434                         ptr = CRYPTO_get_ex_data(ad, i);
 435                         storage[i]->new_func(obj,ptr,ad,i,
 436                                 storage[i]->argl,storage[i]->argp);
 437                         }
 438                 }
 439         if(storage)
 440                 OPENSSL_free(storage);
 441         return 1;
 442         }
 443
 444 /* Same thread-safety notes as for "int_new_ex_data" */
 445 static int int_dup_ex_data(int class_index, CRYPTO_EX_DATA *to,
 446                 CRYPTO_EX_DATA *from)
 447         {
 448         int mx, j, i;
 449         char *ptr;
 450         CRYPTO_EX_DATA_FUNCS **storage = NULL;
 451         EX_CLASS_ITEM *item;
 452         if(!from->sk)
 453                 /* 'to' should be "blank" which *is* just like 'from' */
 454                 return 1;
 455         if((item = def_get_class(class_index)) == NULL)
 456                 return 0;
 457         CRYPTO_r_lock(CRYPTO_LOCK_EX_DATA);
 458         mx = sk_CRYPTO_EX_DATA_FUNCS_num(item->meth);
 459         j = sk_num(from->sk);
 460         if(j < mx)
 461                 mx = j;
 462         if(mx > 0)
 463                 {
 464                 storage = OPENSSL_malloc(mx * sizeof(CRYPTO_EX_DATA_FUNCS*));
 465                 if(!storage)
 466                         goto skip;
 467                 for(i = 0; i < mx; i++)
 468                         storage[i] = sk_CRYPTO_EX_DATA_FUNCS_value(item->meth,i);
 469                 }
 470 skip:
 471         CRYPTO_r_unlock(CRYPTO_LOCK_EX_DATA);
 472         if((mx > 0) && !storage)
 473                 {
 474                 CRYPTOerr(CRYPTO_F_INT_DUP_EX_DATA,ERR_R_MALLOC_FAILURE);
 475                 return 0;
 476                 }
 477         for(i = 0; i < mx; i++)
 478                 {
 479                 ptr = CRYPTO_get_ex_data(from, i);
 480                 if(storage[i] && storage[i]->dup_func)
 481                         storage[i]->dup_func(to,from,&ptr,i,
 482                                 storage[i]->argl,storage[i]->argp);
 483                 CRYPTO_set_ex_data(to,i,ptr);
 484                 }
 485         if(storage)
 486                 OPENSSL_free(storage);
 487         return 1;
 488         }
 489
 490 /* Same thread-safety notes as for "int_new_ex_data" */
 491 static void int_free_ex_data(int class_index, void *obj,
 492                 CRYPTO_EX_DATA *ad)
 493         {
 494         int mx,i;
 495         EX_CLASS_ITEM *item;
 496         void *ptr;
 497         CRYPTO_EX_DATA_FUNCS **storage = NULL;
 498         if((item = def_get_class(class_index)) == NULL)
 499                 return;
 500         CRYPTO_r_lock(CRYPTO_LOCK_EX_DATA);
 501         mx = sk_CRYPTO_EX_DATA_FUNCS_num(item->meth);
 502         if(mx > 0)
 503                 {
 504                 storage = OPENSSL_malloc(mx * sizeof(CRYPTO_EX_DATA_FUNCS*));
 505                 if(!storage)
 506                         goto skip;
 507                 for(i = 0; i < mx; i++)
 508                         storage[i] = sk_CRYPTO_EX_DATA_FUNCS_value(item->meth,i);
 509                 }
 510 skip:
 511         CRYPTO_r_unlock(CRYPTO_LOCK_EX_DATA);
 512         if((mx > 0) && !storage)
 513                 {
 514                 CRYPTOerr(CRYPTO_F_INT_FREE_EX_DATA,ERR_R_MALLOC_FAILURE);
 515                 return;
 516                 }
 517         for(i = 0; i < mx; i++)
 518                 {
 519                 if(storage[i] && storage[i]->free_func)
 520                         {
 521                         ptr = CRYPTO_get_ex_data(ad,i);
 522                         storage[i]->free_func(obj,ptr,ad,i,
 523                                 storage[i]->argl,storage[i]->argp);
 524                         }
 525                 }
 526         if(storage)
 527                 OPENSSL_free(storage);
 528         if(ad->sk)
 529                 {
 530                 sk_free(ad->sk);
 531                 ad->sk=NULL;
 532                 }
 533         }
 534
 535 /********************************************************************/
 536 /* API functions that defer all "state" operations to the "ex_data"
 537  * implementation we have set. */
 538
 539 /* Obtain an index for a new class (not the same as getting a new index within
 540  * an existing class - this is actually getting a new *class*) */
 541 int CRYPTO_ex_data_new_class(void)
 542         {
 543         IMPL_CHECK
 544         return EX_IMPL(new_class)();
 545         }
 546
 547 /* Release all "ex_data" state to prevent memory leaks. This can't be made
 548  * thread-safe without overhauling a lot of stuff, and shouldn't really be
 549  * called under potential race-conditions anyway (it's for program shutdown
 550  * after all). */
 551 void CRYPTO_cleanup_all_ex_data(void)
 552         {
 553         IMPL_CHECK
 554         EX_IMPL(cleanup)();
 555         }
 556
 557 /* Inside an existing class, get/register a new index. */
 558 int CRYPTO_get_ex_new_index(int class_index, long argl, void *argp,
 559                 CRYPTO_EX_new *new_func, CRYPTO_EX_dup *dup_func,
 560                 CRYPTO_EX_free *free_func)
 561         {
 562         int ret = -1;
 563
 564         IMPL_CHECK
 565         ret = EX_IMPL(get_new_index)(class_index,
 566                         argl, argp, new_func, dup_func, free_func);
 567         return ret;
 568         }
 569
 570 /* Initialise a new CRYPTO_EX_DATA for use in a particular class - including
 571  * calling new() callbacks for each index in the class used by this variable */
 572 int CRYPTO_new_ex_data(int class_index, void *obj, CRYPTO_EX_DATA *ad)
 573         {
 574         IMPL_CHECK
 575         return EX_IMPL(new_ex_data)(class_index, obj, ad);
 576         }
 577
 578 /* Duplicate a CRYPTO_EX_DATA variable - including calling dup() callbacks for
 579  * each index in the class used by this variable */
 580 int CRYPTO_dup_ex_data(int class_index, CRYPTO_EX_DATA *to,
 581              CRYPTO_EX_DATA *from)
 582         {
 583         IMPL_CHECK
 584         return EX_IMPL(dup_ex_data)(class_index, to, from);
 585         }
 586
 587 /* Cleanup a CRYPTO_EX_DATA variable - including calling free() callbacks for
 588  * each index in the class used by this variable */
 589 void CRYPTO_free_ex_data(int class_index, void *obj, CRYPTO_EX_DATA *ad)
 590         {
 591         IMPL_CHECK
 592         EX_IMPL(free_ex_data)(class_index, obj, ad);
 593         }
 594
 595 /* For a given CRYPTO_EX_DATA variable, set the value corresponding to a
 596  * particular index in the class used by this variable */
 597 int CRYPTO_set_ex_data(CRYPTO_EX_DATA *ad, int idx, void *val)
 598         {
 599         int i;
 600
 601         if (ad->sk == NULL)
 602                 {
 603                 if ((ad->sk=sk_new_null()) == NULL)
 604                         {
 605                         CRYPTOerr(CRYPTO_F_CRYPTO_SET_EX_DATA,ERR_R_MALLOC_FAILURE);
 606                         return(0);
 607                         }
 608                 }
 609         i=sk_num(ad->sk);
 610
 611         while (i <= idx)
 612                 {
 613                 if (!sk_push(ad->sk,NULL))
 614                         {
 615                         CRYPTOerr(CRYPTO_F_CRYPTO_SET_EX_DATA,ERR_R_MALLOC_FAILURE);
 616                         return(0);
 617                         }
 618                 i++;
 619                 }
 620         sk_set(ad->sk,idx,val);
 621         return(1);
 622         }
 623
 624 /* For a given CRYPTO_EX_DATA_ variable, get the value corresponding to a
 625  * particular index in the class used by this variable */
 626 void *CRYPTO_get_ex_data(const CRYPTO_EX_DATA *ad, int idx)
 627         {
 628         if (ad->sk == NULL)
 629                 return(0);
 630         else if (idx >= sk_num(ad->sk))
 631                 return(0);
 632         else
 633                 return(sk_value(ad->sk,idx));
 634         }
 635
 636 IMPLEMENT_STACK_OF(CRYPTO_EX_DATA_FUNCS)