2 * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the OpenSSL license (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
10 #include "internal/cryptlib_int.h"
11 #include "internal/thread_once.h"
12 #include <openssl/lhash.h>
15 * Each structure type (sometimes called a class), that supports
16 * exdata has a stack of callbacks for each instance.
18 struct ex_callback_st {
19 long argl; /* Arbitrary long */
20 void *argp; /* Arbitrary void * */
21 CRYPTO_EX_new *new_func;
22 CRYPTO_EX_free *free_func;
23 CRYPTO_EX_dup *dup_func;
27 * The state for each class. This could just be a typedef, but
28 * a structure allows future changes.
30 typedef struct ex_callbacks_st {
31 STACK_OF(EX_CALLBACK) *meth;
34 static EX_CALLBACKS ex_data[CRYPTO_EX_INDEX__COUNT];
36 static CRYPTO_RWLOCK *ex_data_lock = NULL;
37 static CRYPTO_ONCE ex_data_init = CRYPTO_ONCE_STATIC_INIT;
39 DEFINE_RUN_ONCE_STATIC(do_ex_data_init)
41 OPENSSL_init_crypto(0, NULL);
42 ex_data_lock = CRYPTO_THREAD_lock_new();
43 return ex_data_lock != NULL;
47 * Return the EX_CALLBACKS from the |ex_data| array that corresponds to
48 * a given class. On success, *holds the lock.*
50 static EX_CALLBACKS *get_and_lock(int class_index)
54 if (class_index < 0 || class_index >= CRYPTO_EX_INDEX__COUNT) {
55 CRYPTOerr(CRYPTO_F_GET_AND_LOCK, ERR_R_PASSED_INVALID_ARGUMENT);
59 if (!RUN_ONCE(&ex_data_init, do_ex_data_init)) {
60 CRYPTOerr(CRYPTO_F_GET_AND_LOCK, ERR_R_MALLOC_FAILURE);
64 if (ex_data_lock == NULL) {
66 * This can happen in normal operation when using CRYPTO_mem_leaks().
67 * The CRYPTO_mem_leaks() function calls OPENSSL_cleanup() which cleans
68 * up the locks. Subsequently the BIO that CRYPTO_mem_leaks() uses gets
69 * freed, which also attempts to free the ex_data. However
70 * CRYPTO_mem_leaks() ensures that the ex_data is freed early (i.e.
71 * before OPENSSL_cleanup() is called), so if we get here we can safely
72 * ignore this operation. We just treat it as an error.
77 ip = &ex_data[class_index];
78 CRYPTO_THREAD_write_lock(ex_data_lock);
82 static void cleanup_cb(EX_CALLBACK *funcs)
88 * Release all "ex_data" state to prevent memory leaks. This can't be made
89 * thread-safe without overhauling a lot of stuff, and shouldn't really be
90 * called under potential race-conditions anyway (it's for program shutdown
93 void crypto_cleanup_all_ex_data_int(void)
97 for (i = 0; i < CRYPTO_EX_INDEX__COUNT; ++i) {
98 EX_CALLBACKS *ip = &ex_data[i];
100 sk_EX_CALLBACK_pop_free(ip->meth, cleanup_cb);
104 CRYPTO_THREAD_lock_free(ex_data_lock);
110 * Unregister a new index by replacing the callbacks with no-ops.
111 * Any in-use instances are leaked.
113 static void dummy_new(void *parent, void *ptr, CRYPTO_EX_DATA *ad, int idx,
114 long argl, void *argp)
118 static void dummy_free(void *parent, void *ptr, CRYPTO_EX_DATA *ad, int idx,
119 long argl, void *argp)
123 static int dummy_dup(CRYPTO_EX_DATA *to, const CRYPTO_EX_DATA *from,
124 void *from_d, int idx,
125 long argl, void *argp)
130 int CRYPTO_free_ex_index(int class_index, int idx)
132 EX_CALLBACKS *ip = get_and_lock(class_index);
138 if (idx < 0 || idx >= sk_EX_CALLBACK_num(ip->meth))
140 a = sk_EX_CALLBACK_value(ip->meth, idx);
143 a->new_func = dummy_new;
144 a->dup_func = dummy_dup;
145 a->free_func = dummy_free;
148 CRYPTO_THREAD_unlock(ex_data_lock);
153 * Register a new index.
155 int CRYPTO_get_ex_new_index(int class_index, long argl, void *argp,
156 CRYPTO_EX_new *new_func, CRYPTO_EX_dup *dup_func,
157 CRYPTO_EX_free *free_func)
161 EX_CALLBACKS *ip = get_and_lock(class_index);
166 if (ip->meth == NULL) {
167 ip->meth = sk_EX_CALLBACK_new_null();
168 /* We push an initial value on the stack because the SSL
169 * "app_data" routines use ex_data index zero. See RT 3710. */
171 || !sk_EX_CALLBACK_push(ip->meth, NULL)) {
172 CRYPTOerr(CRYPTO_F_CRYPTO_GET_EX_NEW_INDEX, ERR_R_MALLOC_FAILURE);
177 a = (EX_CALLBACK *)OPENSSL_malloc(sizeof(*a));
179 CRYPTOerr(CRYPTO_F_CRYPTO_GET_EX_NEW_INDEX, ERR_R_MALLOC_FAILURE);
184 a->new_func = new_func;
185 a->dup_func = dup_func;
186 a->free_func = free_func;
188 if (!sk_EX_CALLBACK_push(ip->meth, NULL)) {
189 CRYPTOerr(CRYPTO_F_CRYPTO_GET_EX_NEW_INDEX, ERR_R_MALLOC_FAILURE);
193 toret = sk_EX_CALLBACK_num(ip->meth) - 1;
194 (void)sk_EX_CALLBACK_set(ip->meth, toret, a);
197 CRYPTO_THREAD_unlock(ex_data_lock);
202 * Initialise a new CRYPTO_EX_DATA for use in a particular class - including
203 * calling new() callbacks for each index in the class used by this variable
204 * Thread-safe by copying a class's array of "EX_CALLBACK" entries
205 * in the lock, then using them outside the lock. Note this only applies
206 * to the global "ex_data" state (ie. class definitions), not 'ad' itself.
208 int CRYPTO_new_ex_data(int class_index, void *obj, CRYPTO_EX_DATA *ad)
212 EX_CALLBACK **storage = NULL;
213 EX_CALLBACK *stack[10];
214 EX_CALLBACKS *ip = get_and_lock(class_index);
221 mx = sk_EX_CALLBACK_num(ip->meth);
223 if (mx < (int)OSSL_NELEM(stack))
226 storage = OPENSSL_malloc(sizeof(*storage) * mx);
228 for (i = 0; i < mx; i++)
229 storage[i] = sk_EX_CALLBACK_value(ip->meth, i);
231 CRYPTO_THREAD_unlock(ex_data_lock);
233 if (mx > 0 && storage == NULL) {
234 CRYPTOerr(CRYPTO_F_CRYPTO_NEW_EX_DATA, ERR_R_MALLOC_FAILURE);
237 for (i = 0; i < mx; i++) {
238 if (storage[i] && storage[i]->new_func) {
239 ptr = CRYPTO_get_ex_data(ad, i);
240 storage[i]->new_func(obj, ptr, ad, i,
241 storage[i]->argl, storage[i]->argp);
244 if (storage != stack)
245 OPENSSL_free(storage);
250 * Duplicate a CRYPTO_EX_DATA variable - including calling dup() callbacks
251 * for each index in the class used by this variable
253 int CRYPTO_dup_ex_data(int class_index, CRYPTO_EX_DATA *to,
254 const CRYPTO_EX_DATA *from)
258 EX_CALLBACK *stack[10];
259 EX_CALLBACK **storage = NULL;
263 if (from->sk == NULL)
264 /* Nothing to copy over */
266 if ((ip = get_and_lock(class_index)) == NULL)
269 mx = sk_EX_CALLBACK_num(ip->meth);
270 j = sk_void_num(from->sk);
274 if (mx < (int)OSSL_NELEM(stack))
277 storage = OPENSSL_malloc(sizeof(*storage) * mx);
279 for (i = 0; i < mx; i++)
280 storage[i] = sk_EX_CALLBACK_value(ip->meth, i);
282 CRYPTO_THREAD_unlock(ex_data_lock);
286 if (storage == NULL) {
287 CRYPTOerr(CRYPTO_F_CRYPTO_DUP_EX_DATA, ERR_R_MALLOC_FAILURE);
290 if (!CRYPTO_set_ex_data(to, mx - 1, NULL))
293 for (i = 0; i < mx; i++) {
294 ptr = CRYPTO_get_ex_data(from, i);
295 if (storage[i] && storage[i]->dup_func)
296 if (!storage[i]->dup_func(to, from, &ptr, i,
297 storage[i]->argl, storage[i]->argp))
299 CRYPTO_set_ex_data(to, i, ptr);
303 if (storage != stack)
304 OPENSSL_free(storage);
310 * Cleanup a CRYPTO_EX_DATA variable - including calling free() callbacks for
311 * each index in the class used by this variable
313 void CRYPTO_free_ex_data(int class_index, void *obj, CRYPTO_EX_DATA *ad)
319 EX_CALLBACK *stack[10];
320 EX_CALLBACK **storage = NULL;
322 if ((ip = get_and_lock(class_index)) == NULL)
325 mx = sk_EX_CALLBACK_num(ip->meth);
327 if (mx < (int)OSSL_NELEM(stack))
330 storage = OPENSSL_malloc(sizeof(*storage) * mx);
332 for (i = 0; i < mx; i++)
333 storage[i] = sk_EX_CALLBACK_value(ip->meth, i);
335 CRYPTO_THREAD_unlock(ex_data_lock);
337 for (i = 0; i < mx; i++) {
341 CRYPTO_THREAD_write_lock(ex_data_lock);
342 f = sk_EX_CALLBACK_value(ip->meth, i);
343 CRYPTO_THREAD_unlock(ex_data_lock);
345 if (f != NULL && f->free_func != NULL) {
346 ptr = CRYPTO_get_ex_data(ad, i);
347 f->free_func(obj, ptr, ad, i, f->argl, f->argp);
351 if (storage != stack)
352 OPENSSL_free(storage);
354 sk_void_free(ad->sk);
359 * For a given CRYPTO_EX_DATA variable, set the value corresponding to a
360 * particular index in the class used by this variable
362 int CRYPTO_set_ex_data(CRYPTO_EX_DATA *ad, int idx, void *val)
366 if (ad->sk == NULL) {
367 if ((ad->sk = sk_void_new_null()) == NULL) {
368 CRYPTOerr(CRYPTO_F_CRYPTO_SET_EX_DATA, ERR_R_MALLOC_FAILURE);
373 for (i = sk_void_num(ad->sk); i <= idx; ++i) {
374 if (!sk_void_push(ad->sk, NULL)) {
375 CRYPTOerr(CRYPTO_F_CRYPTO_SET_EX_DATA, ERR_R_MALLOC_FAILURE);
379 sk_void_set(ad->sk, idx, val);
384 * For a given CRYPTO_EX_DATA_ variable, get the value corresponding to a
385 * particular index in the class used by this variable
387 void *CRYPTO_get_ex_data(const CRYPTO_EX_DATA *ad, int idx)
389 if (ad->sk == NULL || idx >= sk_void_num(ad->sk))
391 return sk_void_value(ad->sk, idx);