diff options
Diffstat (limited to 'openssl/crypto/ex_data.c')
| -rw-r--r-- | openssl/crypto/ex_data.c | 632 |
1 files changed, 632 insertions, 0 deletions
diff --git a/openssl/crypto/ex_data.c b/openssl/crypto/ex_data.c new file mode 100644 index 000000000..3b11e7a55 --- /dev/null +++ b/openssl/crypto/ex_data.c @@ -0,0 +1,632 @@ +/* crypto/ex_data.c */ + +/* + * Overhaul notes; + * + * This code is now *mostly* thread-safe. It is now easier to understand in what + * ways it is safe and in what ways it is not, which is an improvement. Firstly, + * all per-class stacks and index-counters for ex_data are stored in the same + * global LHASH table (keyed by class). This hash table uses locking for all + * access with the exception of CRYPTO_cleanup_all_ex_data(), which must only be + * called when no other threads can possibly race against it (even if it was + * locked, the race would mean it's possible the hash table might have been + * recreated after the cleanup). As classes can only be added to the hash table, + * and within each class, the stack of methods can only be incremented, the + * locking mechanics are simpler than they would otherwise be. For example, the + * new/dup/free ex_data functions will lock the hash table, copy the method + * pointers it needs from the relevant class, then unlock the hash table before + * actually applying those method pointers to the task of the new/dup/free + * operations. As they can't be removed from the method-stack, only + * supplemented, there's no race conditions associated with using them outside + * the lock. The get/set_ex_data functions are not locked because they do not + * involve this global state at all - they operate directly with a previously + * obtained per-class method index and a particular "ex_data" variable. These + * variables are usually instantiated per-context (eg. each RSA structure has + * one) so locking on read/write access to that variable can be locked locally + * if required (eg. using the "RSA" lock to synchronise access to a + * per-RSA-structure ex_data variable if required). + * [Geoff] + */ + +/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) + * All rights reserved. + * + * This package is an SSL implementation written + * by Eric Young (eay@cryptsoft.com). + * The implementation was written so as to conform with Netscapes SSL. + * + * This library is free for commercial and non-commercial use as long as + * the following conditions are aheared to. The following conditions + * apply to all code found in this distribution, be it the RC4, RSA, + * lhash, DES, etc., code; not just the SSL code. The SSL documentation + * included with this distribution is covered by the same copyright terms + * except that the holder is Tim Hudson (tjh@cryptsoft.com). + * + * Copyright remains Eric Young's, and as such any Copyright notices in + * the code are not to be removed. + * If this package is used in a product, Eric Young should be given attribution + * as the author of the parts of the library used. + * This can be in the form of a textual message at program startup or + * in documentation (online or textual) provided with the package. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * "This product includes cryptographic software written by + * Eric Young (eay@cryptsoft.com)" + * The word 'cryptographic' can be left out if the rouines from the library + * being used are not cryptographic related :-). + * 4. If you include any Windows specific code (or a derivative thereof) from + * the apps directory (application code) you must include an acknowledgement: + * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" + * + * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * The licence and distribution terms for any publically available version or + * derivative of this code cannot be changed. i.e. this code cannot simply be + * copied and put under another distribution licence + * [including the GNU Public Licence.] + */ +/* ==================================================================== + * Copyright (c) 1998-2001 The OpenSSL Project. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * + * 3. All advertising materials mentioning features or use of this + * software must display the following acknowledgment: + * "This product includes software developed by the OpenSSL Project + * for use in the OpenSSL Toolkit. (http://www.openssl.org/)" + * + * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to + * endorse or promote products derived from this software without + * prior written permission. For written permission, please contact + * openssl-core@openssl.org. + * + * 5. Products derived from this software may not be called "OpenSSL" + * nor may "OpenSSL" appear in their names without prior written + * permission of the OpenSSL Project. + * + * 6. Redistributions of any form whatsoever must retain the following + * acknowledgment: + * "This product includes software developed by the OpenSSL Project + * for use in the OpenSSL Toolkit (http://www.openssl.org/)" + * + * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY + * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR + * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR + * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; + * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, + * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED + * OF THE POSSIBILITY OF SUCH DAMAGE. + * ==================================================================== + * + * This product includes cryptographic software written by Eric Young + * (eay@cryptsoft.com). This product includes software written by Tim + * Hudson (tjh@cryptsoft.com). + * + */ + +#include "cryptlib.h" +#include <openssl/lhash.h> + +/* What an "implementation of ex_data functionality" looks like */ +struct st_CRYPTO_EX_DATA_IMPL + { + /*********************/ + /* GLOBAL OPERATIONS */ + /* Return a new class index */ + int (*cb_new_class)(void); + /* Cleanup all state used by the implementation */ + void (*cb_cleanup)(void); + /************************/ + /* PER-CLASS OPERATIONS */ + /* Get a new method index within a class */ + int (*cb_get_new_index)(int class_index, long argl, void *argp, + CRYPTO_EX_new *new_func, CRYPTO_EX_dup *dup_func, + CRYPTO_EX_free *free_func); + /* Initialise a new CRYPTO_EX_DATA of a given class */ + int (*cb_new_ex_data)(int class_index, void *obj, + CRYPTO_EX_DATA *ad); + /* Duplicate a CRYPTO_EX_DATA of a given class onto a copy */ + int (*cb_dup_ex_data)(int class_index, CRYPTO_EX_DATA *to, + CRYPTO_EX_DATA *from); + /* Cleanup a CRYPTO_EX_DATA of a given class */ + void (*cb_free_ex_data)(int class_index, void *obj, + CRYPTO_EX_DATA *ad); + }; + +/* The implementation we use at run-time */ +static const CRYPTO_EX_DATA_IMPL *impl = NULL; + +/* To call "impl" functions, use this macro rather than referring to 'impl' directly, eg. + * EX_IMPL(get_new_index)(...); */ +#define EX_IMPL(a) impl->cb_##a + +/* Predeclare the "default" ex_data implementation */ +static int int_new_class(void); +static void int_cleanup(void); +static int int_get_new_index(int class_index, long argl, void *argp, + CRYPTO_EX_new *new_func, CRYPTO_EX_dup *dup_func, + CRYPTO_EX_free *free_func); +static int int_new_ex_data(int class_index, void *obj, + CRYPTO_EX_DATA *ad); +static int int_dup_ex_data(int class_index, CRYPTO_EX_DATA *to, + CRYPTO_EX_DATA *from); +static void int_free_ex_data(int class_index, void *obj, + CRYPTO_EX_DATA *ad); +static CRYPTO_EX_DATA_IMPL impl_default = + { + int_new_class, + int_cleanup, + int_get_new_index, + int_new_ex_data, + int_dup_ex_data, + int_free_ex_data + }; + +/* Internal function that checks whether "impl" is set and if not, sets it to + * the default. */ +static void impl_check(void) + { + CRYPTO_w_lock(CRYPTO_LOCK_EX_DATA); + if(!impl) + impl = &impl_default; + CRYPTO_w_unlock(CRYPTO_LOCK_EX_DATA); + } +/* A macro wrapper for impl_check that first uses a non-locked test before + * invoking the function (which checks again inside a lock). */ +#define IMPL_CHECK if(!impl) impl_check(); + +/* API functions to get/set the "ex_data" implementation */ +const CRYPTO_EX_DATA_IMPL *CRYPTO_get_ex_data_implementation(void) + { + IMPL_CHECK + return impl; + } +int CRYPTO_set_ex_data_implementation(const CRYPTO_EX_DATA_IMPL *i) + { + int toret = 0; + CRYPTO_w_lock(CRYPTO_LOCK_EX_DATA); + if(!impl) + { + impl = i; + toret = 1; + } + CRYPTO_w_unlock(CRYPTO_LOCK_EX_DATA); + return toret; + } + +/****************************************************************************/ +/* Interal (default) implementation of "ex_data" support. API functions are + * further down. */ + +/* The type that represents what each "class" used to implement locally. A STACK + * of CRYPTO_EX_DATA_FUNCS plus a index-counter. The 'class_index' is the global + * value representing the class that is used to distinguish these items. */ +typedef struct st_ex_class_item { + int class_index; + STACK_OF(CRYPTO_EX_DATA_FUNCS) *meth; + int meth_num; +} EX_CLASS_ITEM; + +/* When assigning new class indexes, this is our counter */ +static int ex_class = CRYPTO_EX_INDEX_USER; + +/* The global hash table of EX_CLASS_ITEM items */ +static LHASH *ex_data = NULL; + +/* The callbacks required in the "ex_data" hash table */ +static unsigned long ex_hash_cb(const void *a_void) + { + return ((const EX_CLASS_ITEM *)a_void)->class_index; + } +static int ex_cmp_cb(const void *a_void, const void *b_void) + { + return (((const EX_CLASS_ITEM *)a_void)->class_index - + ((const EX_CLASS_ITEM *)b_void)->class_index); + } + +/* Internal functions used by the "impl_default" implementation to access the + * state */ + +static int ex_data_check(void) + { + int toret = 1; + CRYPTO_w_lock(CRYPTO_LOCK_EX_DATA); + if(!ex_data && ((ex_data = lh_new(ex_hash_cb, ex_cmp_cb)) == NULL)) + toret = 0; + CRYPTO_w_unlock(CRYPTO_LOCK_EX_DATA); + return toret; + } +/* This macros helps reduce the locking from repeated checks because the + * ex_data_check() function checks ex_data again inside a lock. */ +#define EX_DATA_CHECK(iffail) if(!ex_data && !ex_data_check()) {iffail} + +/* This "inner" callback is used by the callback function that follows it */ +static void def_cleanup_util_cb(CRYPTO_EX_DATA_FUNCS *funcs) + { + OPENSSL_free(funcs); + } + +/* This callback is used in lh_doall to destroy all EX_CLASS_ITEM values from + * "ex_data" prior to the ex_data hash table being itself destroyed. Doesn't do + * any locking. */ +static void def_cleanup_cb(void *a_void) + { + EX_CLASS_ITEM *item = (EX_CLASS_ITEM *)a_void; + sk_CRYPTO_EX_DATA_FUNCS_pop_free(item->meth, def_cleanup_util_cb); + OPENSSL_free(item); + } + +/* Return the EX_CLASS_ITEM from the "ex_data" hash table that corresponds to a + * given class. Handles locking. */ +static EX_CLASS_ITEM *def_get_class(int class_index) + { + EX_CLASS_ITEM d, *p, *gen; + EX_DATA_CHECK(return NULL;) + d.class_index = class_index; + CRYPTO_w_lock(CRYPTO_LOCK_EX_DATA); + p = lh_retrieve(ex_data, &d); + if(!p) + { + gen = OPENSSL_malloc(sizeof(EX_CLASS_ITEM)); + if(gen) + { + gen->class_index = class_index; + gen->meth_num = 0; + gen->meth = sk_CRYPTO_EX_DATA_FUNCS_new_null(); + if(!gen->meth) + OPENSSL_free(gen); + else + { + /* Because we're inside the ex_data lock, the + * return value from the insert will be NULL */ + lh_insert(ex_data, gen); + p = gen; + } + } + } + CRYPTO_w_unlock(CRYPTO_LOCK_EX_DATA); + if(!p) + CRYPTOerr(CRYPTO_F_DEF_GET_CLASS,ERR_R_MALLOC_FAILURE); + return p; + } + +/* Add a new method to the given EX_CLASS_ITEM and return the corresponding + * index (or -1 for error). Handles locking. */ +static int def_add_index(EX_CLASS_ITEM *item, long argl, void *argp, + CRYPTO_EX_new *new_func, CRYPTO_EX_dup *dup_func, + CRYPTO_EX_free *free_func) + { + int toret = -1; + CRYPTO_EX_DATA_FUNCS *a = (CRYPTO_EX_DATA_FUNCS *)OPENSSL_malloc( + sizeof(CRYPTO_EX_DATA_FUNCS)); + if(!a) + { + CRYPTOerr(CRYPTO_F_DEF_ADD_INDEX,ERR_R_MALLOC_FAILURE); + return -1; + } + a->argl=argl; + a->argp=argp; + a->new_func=new_func; + a->dup_func=dup_func; + a->free_func=free_func; + CRYPTO_w_lock(CRYPTO_LOCK_EX_DATA); + while (sk_CRYPTO_EX_DATA_FUNCS_num(item->meth) <= item->meth_num) + { + if (!sk_CRYPTO_EX_DATA_FUNCS_push(item->meth, NULL)) + { + CRYPTOerr(CRYPTO_F_DEF_ADD_INDEX,ERR_R_MALLOC_FAILURE); + OPENSSL_free(a); + goto err; + } + } + toret = item->meth_num++; + (void)sk_CRYPTO_EX_DATA_FUNCS_set(item->meth, toret, a); +err: + CRYPTO_w_unlock(CRYPTO_LOCK_EX_DATA); + return toret; + } + +/**************************************************************/ +/* The functions in the default CRYPTO_EX_DATA_IMPL structure */ + +static int int_new_class(void) + { + int toret; + CRYPTO_w_lock(CRYPTO_LOCK_EX_DATA); + toret = ex_class++; + CRYPTO_w_unlock(CRYPTO_LOCK_EX_DATA); + return toret; + } + +static void int_cleanup(void) + { + EX_DATA_CHECK(return;) + lh_doall(ex_data, def_cleanup_cb); + lh_free(ex_data); + ex_data = NULL; + impl = NULL; + } + +static int int_get_new_index(int class_index, long argl, void *argp, + CRYPTO_EX_new *new_func, CRYPTO_EX_dup *dup_func, + CRYPTO_EX_free *free_func) + { + EX_CLASS_ITEM *item = def_get_class(class_index); + if(!item) + return -1; + return def_add_index(item, argl, argp, new_func, dup_func, free_func); + } + +/* Thread-safe by copying a class's array of "CRYPTO_EX_DATA_FUNCS" entries in + * the lock, then using them outside the lock. NB: Thread-safety only applies to + * the global "ex_data" state (ie. class definitions), not thread-safe on 'ad' + * itself. */ +static int int_new_ex_data(int class_index, void *obj, + CRYPTO_EX_DATA *ad) + { + int mx,i; + void *ptr; + CRYPTO_EX_DATA_FUNCS **storage = NULL; + EX_CLASS_ITEM *item = def_get_class(class_index); + if(!item) + /* error is already set */ + return 0; + ad->sk = NULL; + CRYPTO_r_lock(CRYPTO_LOCK_EX_DATA); + mx = sk_CRYPTO_EX_DATA_FUNCS_num(item->meth); + if(mx > 0) + { + storage = OPENSSL_malloc(mx * sizeof(CRYPTO_EX_DATA_FUNCS*)); + if(!storage) + goto skip; + for(i = 0; i < mx; i++) + storage[i] = sk_CRYPTO_EX_DATA_FUNCS_value(item->meth,i); + } +skip: + CRYPTO_r_unlock(CRYPTO_LOCK_EX_DATA); + if((mx > 0) && !storage) + { + CRYPTOerr(CRYPTO_F_INT_NEW_EX_DATA,ERR_R_MALLOC_FAILURE); + return 0; + } + for(i = 0; i < mx; i++) + { + if(storage[i] && storage[i]->new_func) + { + ptr = CRYPTO_get_ex_data(ad, i); + storage[i]->new_func(obj,ptr,ad,i, + storage[i]->argl,storage[i]->argp); + } + } + if(storage) + OPENSSL_free(storage); + return 1; + } + +/* Same thread-safety notes as for "int_new_ex_data" */ +static int int_dup_ex_data(int class_index, CRYPTO_EX_DATA *to, + CRYPTO_EX_DATA *from) + { + int mx, j, i; + char *ptr; + CRYPTO_EX_DATA_FUNCS **storage = NULL; + EX_CLASS_ITEM *item; + if(!from->sk) + /* 'to' should be "blank" which *is* just like 'from' */ + return 1; + if((item = def_get_class(class_index)) == NULL) + return 0; + CRYPTO_r_lock(CRYPTO_LOCK_EX_DATA); + mx = sk_CRYPTO_EX_DATA_FUNCS_num(item->meth); + j = sk_num(from->sk); + if(j < mx) + mx = j; + if(mx > 0) + { + storage = OPENSSL_malloc(mx * sizeof(CRYPTO_EX_DATA_FUNCS*)); + if(!storage) + goto skip; + for(i = 0; i < mx; i++) + storage[i] = sk_CRYPTO_EX_DATA_FUNCS_value(item->meth,i); + } +skip: + CRYPTO_r_unlock(CRYPTO_LOCK_EX_DATA); + if((mx > 0) && !storage) + { + CRYPTOerr(CRYPTO_F_INT_DUP_EX_DATA,ERR_R_MALLOC_FAILURE); + return 0; + } + for(i = 0; i < mx; i++) + { + ptr = CRYPTO_get_ex_data(from, i); + if(storage[i] && storage[i]->dup_func) + storage[i]->dup_func(to,from,&ptr,i, + storage[i]->argl,storage[i]->argp); + CRYPTO_set_ex_data(to,i,ptr); + } + if(storage) + OPENSSL_free(storage); + return 1; + } + +/* Same thread-safety notes as for "int_new_ex_data" */ +static void int_free_ex_data(int class_index, void *obj, + CRYPTO_EX_DATA *ad) + { + int mx,i; + EX_CLASS_ITEM *item; + void *ptr; + CRYPTO_EX_DATA_FUNCS **storage = NULL; + if((item = def_get_class(class_index)) == NULL) + return; + CRYPTO_r_lock(CRYPTO_LOCK_EX_DATA); + mx = sk_CRYPTO_EX_DATA_FUNCS_num(item->meth); + if(mx > 0) + { + storage = OPENSSL_malloc(mx * sizeof(CRYPTO_EX_DATA_FUNCS*)); + if(!storage) + goto skip; + for(i = 0; i < mx; i++) + storage[i] = sk_CRYPTO_EX_DATA_FUNCS_value(item->meth,i); + } +skip: + CRYPTO_r_unlock(CRYPTO_LOCK_EX_DATA); + if((mx > 0) && !storage) + { + CRYPTOerr(CRYPTO_F_INT_FREE_EX_DATA,ERR_R_MALLOC_FAILURE); + return; + } + for(i = 0; i < mx; i++) + { + if(storage[i] && storage[i]->free_func) + { + ptr = CRYPTO_get_ex_data(ad,i); + storage[i]->free_func(obj,ptr,ad,i, + storage[i]->argl,storage[i]->argp); + } + } + if(storage) + OPENSSL_free(storage); + if(ad->sk) + { + sk_free(ad->sk); + ad->sk=NULL; + } + } + +/********************************************************************/ +/* API functions that defer all "state" operations to the "ex_data" + * implementation we have set. */ + +/* Obtain an index for a new class (not the same as getting a new index within + * an existing class - this is actually getting a new *class*) */ +int CRYPTO_ex_data_new_class(void) + { + IMPL_CHECK + return EX_IMPL(new_class)(); + } + +/* Release all "ex_data" state to prevent memory leaks. This can't be made + * thread-safe without overhauling a lot of stuff, and shouldn't really be + * called under potential race-conditions anyway (it's for program shutdown + * after all). */ +void CRYPTO_cleanup_all_ex_data(void) + { + IMPL_CHECK + EX_IMPL(cleanup)(); + } + +/* Inside an existing class, get/register a new index. */ +int CRYPTO_get_ex_new_index(int class_index, long argl, void *argp, + CRYPTO_EX_new *new_func, CRYPTO_EX_dup *dup_func, + CRYPTO_EX_free *free_func) + { + int ret = -1; + + IMPL_CHECK + ret = EX_IMPL(get_new_index)(class_index, + argl, argp, new_func, dup_func, free_func); + return ret; + } + +/* Initialise a new CRYPTO_EX_DATA for use in a particular class - including + * calling new() callbacks for each index in the class used by this variable */ +int CRYPTO_new_ex_data(int class_index, void *obj, CRYPTO_EX_DATA *ad) + { + IMPL_CHECK + return EX_IMPL(new_ex_data)(class_index, obj, ad); + } + +/* Duplicate a CRYPTO_EX_DATA variable - including calling dup() callbacks for + * each index in the class used by this variable */ +int CRYPTO_dup_ex_data(int class_index, CRYPTO_EX_DATA *to, + CRYPTO_EX_DATA *from) + { + IMPL_CHECK + return EX_IMPL(dup_ex_data)(class_index, to, from); + } + +/* Cleanup a CRYPTO_EX_DATA variable - including calling free() callbacks for + * each index in the class used by this variable */ +void CRYPTO_free_ex_data(int class_index, void *obj, CRYPTO_EX_DATA *ad) + { + IMPL_CHECK + EX_IMPL(free_ex_data)(class_index, obj, ad); + } + +/* For a given CRYPTO_EX_DATA variable, set the value corresponding to a + * particular index in the class used by this variable */ +int CRYPTO_set_ex_data(CRYPTO_EX_DATA *ad, int idx, void *val) + { + int i; + + if (ad->sk == NULL) + { + if ((ad->sk=sk_new_null()) == NULL) + { + CRYPTOerr(CRYPTO_F_CRYPTO_SET_EX_DATA,ERR_R_MALLOC_FAILURE); + return(0); + } + } + i=sk_num(ad->sk); + + while (i <= idx) + { + if (!sk_push(ad->sk,NULL)) + { + CRYPTOerr(CRYPTO_F_CRYPTO_SET_EX_DATA,ERR_R_MALLOC_FAILURE); + return(0); + } + i++; + } + sk_set(ad->sk,idx,val); + return(1); + } + +/* For a given CRYPTO_EX_DATA_ variable, get the value corresponding to a + * particular index in the class used by this variable */ +void *CRYPTO_get_ex_data(const CRYPTO_EX_DATA *ad, int idx) + { + if (ad->sk == NULL) + return(0); + else if (idx >= sk_num(ad->sk)) + return(0); + else + return(sk_value(ad->sk,idx)); + } + +IMPLEMENT_STACK_OF(CRYPTO_EX_DATA_FUNCS) |