2 * Copyright 2011-2017 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
11 #include <openssl/crypto.h>
12 #include <openssl/err.h>
13 #include <openssl/rand.h>
15 #include "internal/thread_once.h"
16 #include "internal/rand_int.h"
19 * Support framework for NIST SP 800-90A DRBG, AES-CTR mode.
20 * The RAND_DRBG is OpenSSL's pointer to an instance of the DRBG.
22 * The OpenSSL model is to have new and free functions, and that new
23 * does all initialization. That is not the NIST model, which has
24 * instantiation and un-instantiate, and re-use within a new/free
25 * lifecycle. (No doubt this comes from the desire to support hardware
26 * DRBG, where allocation of resources on something like an HSM is
27 * a much bigger deal than just re-setting an allocated resource.)
31 * THE THREE SHARED DRBGs
33 * There are three shared DRBGs (master, public and private), which are
34 * accessed concurrently by all threads.
38 * Not used directly by the application, only for reseeding the two other
39 * DRBGs. It reseeds itself by pulling either randomness from os entropy
40 * sources or by consuming randomnes which was added by RAND_add()
42 static RAND_DRBG drbg_master;
46 * Used by default for generating random bytes using RAND_bytes().
48 static RAND_DRBG drbg_public;
52 * Used by default for generating private keys using RAND_priv_bytes()
54 static RAND_DRBG drbg_private;
58 * In addition there are DRBGs, which are not shared, but used only by a
59 * single thread at every time, for example the DRBGs which are owned by
60 * an SSL context. All DRBGs are organized in a hierarchical fashion
61 * with the <master> DRBG as root.
63 * This gives the following overall picture:
65 * <os entropy sources>
67 * RAND_add() ==> <master> \
68 * / \ | shared DRBGs (with locking)
69 * <public> <private> /
71 * <ssl> owned by an SSL context
75 * Before satisfying a generate request, a DRBG reseeds itself automatically,
76 * if one of the following two conditions holds:
78 * - the number of generate requests since the last reseeding exceeds a
79 * certain threshold, the so called |reseed_interval|. This behaviour
80 * can be disabled by setting the |reseed_interval| to 0.
82 * - the time elapsed since the last reseeding exceeds a certain time
83 * interval, the so called |reseed_time_interval|. This behaviour
84 * can be disabled by setting the |reseed_time_interval| to 0.
88 * For the three shared DRBGs (and only for these) there is another way to
89 * reseed them manually by calling RAND_seed() (or RAND_add() with a positive
90 * |randomness| argument). This will immediately reseed the <master> DRBG.
91 * The <public> and <private> DRBG will detect this on their next generate
92 * call and reseed, pulling randomness from <master>.
96 /* NIST SP 800-90A DRBG recommends the use of a personalization string. */
97 static const char ossl_pers_string[] = "OpenSSL NIST SP 800-90A DRBG";
99 static CRYPTO_ONCE rand_drbg_init = CRYPTO_ONCE_STATIC_INIT;
101 static int drbg_setup(RAND_DRBG *drbg, const char *name, RAND_DRBG *parent);
104 * Set/initialize |drbg| to be of type |nid|, with optional |flags|.
105 * Return -2 if the type is not supported, 1 on success and -1 on
108 int RAND_DRBG_set(RAND_DRBG *drbg, int nid, unsigned int flags)
112 drbg->state = DRBG_UNINITIALISED;
118 RANDerr(RAND_F_RAND_DRBG_SET, RAND_R_UNSUPPORTED_DRBG_TYPE);
121 /* Uninitialized; that's okay. */
123 case NID_aes_128_ctr:
124 case NID_aes_192_ctr:
125 case NID_aes_256_ctr:
126 ret = ctr_init(drbg);
131 RANDerr(RAND_F_RAND_DRBG_SET, RAND_R_ERROR_INITIALISING_DRBG);
136 * Allocate memory and initialize a new DRBG. The |parent|, if not
137 * NULL, will be used to auto-seed this RAND_DRBG as needed.
139 * Returns a pointer to the new DRBG instance on success, NULL on failure.
141 RAND_DRBG *RAND_DRBG_new(int type, unsigned int flags, RAND_DRBG *parent)
143 RAND_DRBG *drbg = OPENSSL_zalloc(sizeof(*drbg));
146 RANDerr(RAND_F_RAND_DRBG_NEW, ERR_R_MALLOC_FAILURE);
149 drbg->fork_count = rand_fork_count;
150 drbg->parent = parent;
151 if (RAND_DRBG_set(drbg, type, flags) < 0)
154 if (!RAND_DRBG_set_callbacks(drbg, rand_drbg_get_entropy,
155 rand_drbg_cleanup_entropy,
167 * Uninstantiate |drbg| and free all memory.
169 void RAND_DRBG_free(RAND_DRBG *drbg)
174 ctr_uninstantiate(drbg);
175 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DRBG, drbg, &drbg->ex_data);
176 OPENSSL_clear_free(drbg, sizeof(*drbg));
180 * Instantiate |drbg|, after it has been initialized. Use |pers| and
181 * |perslen| as prediction-resistance input.
183 * Requires that drbg->lock is already locked for write, if non-null.
185 int RAND_DRBG_instantiate(RAND_DRBG *drbg,
186 const unsigned char *pers, size_t perslen)
188 unsigned char *nonce = NULL, *entropy = NULL;
189 size_t noncelen = 0, entropylen = 0;
191 if (perslen > drbg->max_perslen) {
192 RANDerr(RAND_F_RAND_DRBG_INSTANTIATE,
193 RAND_R_PERSONALISATION_STRING_TOO_LONG);
196 if (drbg->state != DRBG_UNINITIALISED) {
197 RANDerr(RAND_F_RAND_DRBG_INSTANTIATE,
198 drbg->state == DRBG_ERROR ? RAND_R_IN_ERROR_STATE
199 : RAND_R_ALREADY_INSTANTIATED);
203 drbg->state = DRBG_ERROR;
204 if (drbg->get_entropy != NULL)
205 entropylen = drbg->get_entropy(drbg, &entropy, drbg->strength,
206 drbg->min_entropylen, drbg->max_entropylen);
207 if (entropylen < drbg->min_entropylen
208 || entropylen > drbg->max_entropylen) {
209 RANDerr(RAND_F_RAND_DRBG_INSTANTIATE, RAND_R_ERROR_RETRIEVING_ENTROPY);
213 if (drbg->max_noncelen > 0 && drbg->get_nonce != NULL) {
214 noncelen = drbg->get_nonce(drbg, &nonce, drbg->strength / 2,
215 drbg->min_noncelen, drbg->max_noncelen);
216 if (noncelen < drbg->min_noncelen || noncelen > drbg->max_noncelen) {
217 RANDerr(RAND_F_RAND_DRBG_INSTANTIATE,
218 RAND_R_ERROR_RETRIEVING_NONCE);
223 if (!ctr_instantiate(drbg, entropy, entropylen,
224 nonce, noncelen, pers, perslen)) {
225 RANDerr(RAND_F_RAND_DRBG_INSTANTIATE, RAND_R_ERROR_INSTANTIATING_DRBG);
229 drbg->state = DRBG_READY;
230 drbg->generate_counter = 0;
231 drbg->reseed_time = time(NULL);
232 if (drbg->reseed_counter > 0) {
233 if (drbg->parent == NULL)
234 drbg->reseed_counter++;
236 drbg->reseed_counter = drbg->parent->reseed_counter;
240 if (entropy != NULL && drbg->cleanup_entropy != NULL)
241 drbg->cleanup_entropy(drbg, entropy, entropylen);
242 if (nonce != NULL && drbg->cleanup_nonce!= NULL )
243 drbg->cleanup_nonce(drbg, nonce, noncelen);
244 if (drbg->pool != NULL) {
245 if (drbg->state == DRBG_READY) {
246 RANDerr(RAND_F_RAND_DRBG_INSTANTIATE,
247 RAND_R_ERROR_ENTROPY_POOL_WAS_IGNORED);
248 drbg->state = DRBG_ERROR;
250 RAND_POOL_free(drbg->pool);
253 if (drbg->state == DRBG_READY)
259 * Uninstantiate |drbg|. Must be instantiated before it can be used.
261 * Requires that drbg->lock is already locked for write, if non-null.
263 int RAND_DRBG_uninstantiate(RAND_DRBG *drbg)
265 int ret = ctr_uninstantiate(drbg);
267 drbg->state = DRBG_UNINITIALISED;
272 * Reseed |drbg|, mixing in the specified data
274 * Requires that drbg->lock is already locked for write, if non-null.
276 int RAND_DRBG_reseed(RAND_DRBG *drbg,
277 const unsigned char *adin, size_t adinlen)
279 unsigned char *entropy = NULL;
280 size_t entropylen = 0;
282 if (drbg->state == DRBG_ERROR) {
283 RANDerr(RAND_F_RAND_DRBG_RESEED, RAND_R_IN_ERROR_STATE);
286 if (drbg->state == DRBG_UNINITIALISED) {
287 RANDerr(RAND_F_RAND_DRBG_RESEED, RAND_R_NOT_INSTANTIATED);
293 else if (adinlen > drbg->max_adinlen) {
294 RANDerr(RAND_F_RAND_DRBG_RESEED, RAND_R_ADDITIONAL_INPUT_TOO_LONG);
298 drbg->state = DRBG_ERROR;
299 if (drbg->get_entropy != NULL)
300 entropylen = drbg->get_entropy(drbg, &entropy, drbg->strength,
301 drbg->min_entropylen, drbg->max_entropylen);
302 if (entropylen < drbg->min_entropylen
303 || entropylen > drbg->max_entropylen) {
304 RANDerr(RAND_F_RAND_DRBG_RESEED, RAND_R_ERROR_RETRIEVING_ENTROPY);
308 if (!ctr_reseed(drbg, entropy, entropylen, adin, adinlen))
311 drbg->state = DRBG_READY;
312 drbg->generate_counter = 0;
313 drbg->reseed_time = time(NULL);
314 if (drbg->reseed_counter > 0) {
315 if (drbg->parent == NULL)
316 drbg->reseed_counter++;
318 drbg->reseed_counter = drbg->parent->reseed_counter;
322 if (entropy != NULL && drbg->cleanup_entropy != NULL)
323 drbg->cleanup_entropy(drbg, entropy, entropylen);
324 if (drbg->state == DRBG_READY)
330 * Restart |drbg|, using the specified entropy or additional input
332 * Tries its best to get the drbg instantiated by all means,
333 * regardless of its current state.
335 * Optionally, a |buffer| of |len| random bytes can be passed,
336 * which is assumed to contain at least |entropy| bits of entropy.
338 * If |entropy| > 0, the buffer content is used as entropy input.
340 * If |entropy| == 0, the buffer content is used as additional input
342 * Returns 1 on success, 0 on failure.
344 * This function is used internally only.
346 int rand_drbg_restart(RAND_DRBG *drbg,
347 const unsigned char *buffer, size_t len, size_t entropy)
350 const unsigned char *adin = NULL;
353 if (drbg->pool != NULL) {
354 RANDerr(RAND_F_RAND_DRBG_RESTART, ERR_R_INTERNAL_ERROR);
355 RAND_POOL_free(drbg->pool);
359 if (buffer != NULL) {
361 if (drbg->max_entropylen < len) {
362 RANDerr(RAND_F_RAND_DRBG_RESTART,
363 RAND_R_ENTROPY_INPUT_TOO_LONG);
367 if (entropy > 8 * len) {
368 RANDerr(RAND_F_RAND_DRBG_RESTART, RAND_R_ENTROPY_OUT_OF_RANGE);
372 /* will be picked up by the rand_drbg_get_entropy() callback */
373 drbg->pool = RAND_POOL_new(entropy, len, len);
374 if (drbg->pool == NULL)
377 RAND_POOL_add(drbg->pool, buffer, len, entropy);
379 if (drbg->max_adinlen < len) {
380 RANDerr(RAND_F_RAND_DRBG_RESTART,
381 RAND_R_ADDITIONAL_INPUT_TOO_LONG);
389 /* repair error state */
390 if (drbg->state == DRBG_ERROR) {
391 RAND_DRBG_uninstantiate(drbg);
392 /* The drbg->ctr member needs to be reinitialized before reinstantiation */
393 RAND_DRBG_set(drbg, drbg->nid, drbg->flags);
396 /* repair uninitialized state */
397 if (drbg->state == DRBG_UNINITIALISED) {
398 /* reinstantiate drbg */
399 RAND_DRBG_instantiate(drbg,
400 (const unsigned char *) ossl_pers_string,
401 sizeof(ossl_pers_string) - 1);
402 /* already reseeded. prevent second reseeding below */
403 reseeded = (drbg->state == DRBG_READY);
406 /* refresh current state if entropy or additional input has been provided */
407 if (drbg->state == DRBG_READY) {
410 * mix in additional input without reseeding
412 * Similar to RAND_DRBG_reseed(), but the provided additional
413 * data |adin| is mixed into the current state without pulling
414 * entropy from the trusted entropy source using get_entropy().
415 * This is not a reseeding in the strict sense of NIST SP 800-90A.
417 ctr_reseed(drbg, adin, adinlen, NULL, 0);
418 } else if (reseeded == 0) {
419 /* do a full reseeding if it has not been done yet above */
420 RAND_DRBG_reseed(drbg, NULL, 0);
424 /* check whether a given entropy pool was cleared properly during reseed */
425 if (drbg->pool != NULL) {
426 drbg->state = DRBG_ERROR;
427 RANDerr(RAND_F_RAND_DRBG_RESTART, ERR_R_INTERNAL_ERROR);
428 RAND_POOL_free(drbg->pool);
433 return drbg->state == DRBG_READY;
437 * Generate |outlen| bytes into the buffer at |out|. Reseed if we need
438 * to or if |prediction_resistance| is set. Additional input can be
439 * sent in |adin| and |adinlen|.
441 * Requires that drbg->lock is already locked for write, if non-null.
443 * Returns 1 on success, 0 on failure.
446 int RAND_DRBG_generate(RAND_DRBG *drbg, unsigned char *out, size_t outlen,
447 int prediction_resistance,
448 const unsigned char *adin, size_t adinlen)
450 int reseed_required = 0;
452 if (drbg->state != DRBG_READY) {
453 /* try to recover from previous errors */
454 rand_drbg_restart(drbg, NULL, 0, 0);
456 if (drbg->state == DRBG_ERROR) {
457 RANDerr(RAND_F_RAND_DRBG_GENERATE, RAND_R_IN_ERROR_STATE);
460 if (drbg->state == DRBG_UNINITIALISED) {
461 RANDerr(RAND_F_RAND_DRBG_GENERATE, RAND_R_NOT_INSTANTIATED);
466 if (outlen > drbg->max_request) {
467 RANDerr(RAND_F_RAND_DRBG_GENERATE, RAND_R_REQUEST_TOO_LARGE_FOR_DRBG);
470 if (adinlen > drbg->max_adinlen) {
471 RANDerr(RAND_F_RAND_DRBG_GENERATE, RAND_R_ADDITIONAL_INPUT_TOO_LONG);
475 if (drbg->fork_count != rand_fork_count) {
476 drbg->fork_count = rand_fork_count;
480 if (drbg->reseed_interval > 0) {
481 if (drbg->generate_counter >= drbg->reseed_interval)
484 if (drbg->reseed_time_interval > 0) {
485 time_t now = time(NULL);
486 if (now < drbg->reseed_time
487 || now - drbg->reseed_time >= drbg->reseed_time_interval)
490 if (drbg->reseed_counter > 0 && drbg->parent != NULL) {
491 if (drbg->reseed_counter != drbg->parent->reseed_counter)
495 if (reseed_required || prediction_resistance) {
496 if (!RAND_DRBG_reseed(drbg, adin, adinlen)) {
497 RANDerr(RAND_F_RAND_DRBG_GENERATE, RAND_R_RESEED_ERROR);
504 if (!ctr_generate(drbg, out, outlen, adin, adinlen)) {
505 drbg->state = DRBG_ERROR;
506 RANDerr(RAND_F_RAND_DRBG_GENERATE, RAND_R_GENERATE_ERROR);
510 drbg->generate_counter++;
516 * Set the RAND_DRBG callbacks for obtaining entropy and nonce.
518 * In the following, the signature and the semantics of the
519 * get_entropy() and cleanup_entropy() callbacks are explained.
523 * size_t get_entropy(RAND_DRBG *ctx,
524 * unsigned char **pout,
526 * size_t min_len, size_t max_len);
528 * This is a request to allocate and fill a buffer of size
529 * |min_len| <= size <= |max_len| (in bytes) which contains
530 * at least |entropy| bits of randomness. The buffer's address is
531 * to be returned in |*pout| and the number of collected
532 * randomness bytes (which may be less than the allocated size
533 * of the buffer) as return value.
535 * If the callback fails to acquire at least |entropy| bits of
536 * randomness, it shall return a buffer length of 0.
540 * void cleanup_entropy(RAND_DRBG *ctx,
541 * unsigned char *out, size_t outlen);
543 * A request to clear and free the buffer allocated by get_entropy().
544 * The values |out| and |outlen| are expected to be the random buffer's
545 * address and length, as returned by the get_entropy() callback.
547 * GET_NONCE, CLEANUP_NONCE
549 * Signature and semantics of the get_nonce() and cleanup_nonce()
550 * callbacks are analogous to get_entropy() and cleanup_entropy().
551 * Currently, the nonce is used only for the known answer tests.
553 int RAND_DRBG_set_callbacks(RAND_DRBG *drbg,
554 RAND_DRBG_get_entropy_fn get_entropy,
555 RAND_DRBG_cleanup_entropy_fn cleanup_entropy,
556 RAND_DRBG_get_nonce_fn get_nonce,
557 RAND_DRBG_cleanup_nonce_fn cleanup_nonce)
559 if (drbg->state != DRBG_UNINITIALISED)
561 drbg->get_entropy = get_entropy;
562 drbg->cleanup_entropy = cleanup_entropy;
563 drbg->get_nonce = get_nonce;
564 drbg->cleanup_nonce = cleanup_nonce;
569 * Set the reseed interval.
571 * The drbg will reseed automatically whenever the number of generate
572 * requests exceeds the given reseed interval. If the reseed interval
573 * is 0, then this feature is disabled.
575 * Returns 1 on success, 0 on failure.
577 int RAND_DRBG_set_reseed_interval(RAND_DRBG *drbg, unsigned int interval)
579 if (interval > MAX_RESEED_INTERVAL)
581 drbg->reseed_interval = interval;
586 * Set the reseed time interval.
588 * The drbg will reseed automatically whenever the time elapsed since
589 * the last reseeding exceeds the given reseed time interval. For safety,
590 * a reseeding will also occur if the clock has been reset to a smaller
593 * Returns 1 on success, 0 on failure.
595 int RAND_DRBG_set_reseed_time_interval(RAND_DRBG *drbg, time_t interval)
597 if (interval > MAX_RESEED_TIME_INTERVAL)
599 drbg->reseed_time_interval = interval;
604 * Get and set the EXDATA
606 int RAND_DRBG_set_ex_data(RAND_DRBG *drbg, int idx, void *arg)
608 return CRYPTO_set_ex_data(&drbg->ex_data, idx, arg);
611 void *RAND_DRBG_get_ex_data(const RAND_DRBG *drbg, int idx)
613 return CRYPTO_get_ex_data(&drbg->ex_data, idx);
618 * The following functions provide a RAND_METHOD that works on the
619 * global DRBG. They lock.
623 * Initializes the given global DRBG with default settings.
624 * A global lock for the DRBG is created with the given name.
626 * Returns a pointer to the new DRBG instance on success, NULL on failure.
628 static int drbg_setup(RAND_DRBG *drbg, const char *name, RAND_DRBG *parent)
632 if (name == NULL || drbg->lock != NULL) {
633 RANDerr(RAND_F_DRBG_SETUP, ERR_R_INTERNAL_ERROR);
637 drbg->lock = CRYPTO_THREAD_glock_new(name);
638 if (drbg->lock == NULL) {
639 RANDerr(RAND_F_DRBG_SETUP, RAND_R_FAILED_TO_CREATE_LOCK);
643 ret &= RAND_DRBG_set(drbg,
644 RAND_DRBG_NID, RAND_DRBG_FLAG_CTR_USE_DF) == 1;
645 ret &= RAND_DRBG_set_callbacks(drbg, rand_drbg_get_entropy,
646 rand_drbg_cleanup_entropy, NULL, NULL) == 1;
648 if (parent == NULL) {
649 drbg->reseed_interval = MASTER_RESEED_INTERVAL;
650 drbg->reseed_time_interval = MASTER_RESEED_TIME_INTERVAL;
652 drbg->parent = parent;
653 drbg->reseed_interval = SLAVE_RESEED_INTERVAL;
654 drbg->reseed_time_interval = SLAVE_RESEED_TIME_INTERVAL;
657 /* enable seed propagation */
658 drbg->reseed_counter = 1;
661 * Ignore instantiation error so support just-in-time instantiation.
663 * The state of the drbg will be checked in RAND_DRBG_generate() and
664 * an automatic recovery is attempted.
666 RAND_DRBG_instantiate(drbg,
667 (const unsigned char *) ossl_pers_string,
668 sizeof(ossl_pers_string) - 1);
673 * Initialize the global DRBGs on first use.
674 * Returns 1 on success, 0 on failure.
676 DEFINE_RUN_ONCE_STATIC(do_rand_drbg_init)
680 ret &= drbg_setup(&drbg_master, "drbg_master", NULL);
681 ret &= drbg_setup(&drbg_public, "drbg_public", &drbg_master);
682 ret &= drbg_setup(&drbg_private, "drbg_private", &drbg_master);
687 /* Cleans up the given global DRBG */
688 static void drbg_cleanup(RAND_DRBG *drbg)
690 CRYPTO_THREAD_lock_free(drbg->lock);
691 RAND_DRBG_uninstantiate(drbg);
694 /* Clean up the global DRBGs before exit */
695 void rand_drbg_cleanup_int(void)
697 drbg_cleanup(&drbg_private);
698 drbg_cleanup(&drbg_public);
699 drbg_cleanup(&drbg_master);
702 /* Implements the default OpenSSL RAND_bytes() method */
703 static int drbg_bytes(unsigned char *out, int count)
707 RAND_DRBG *drbg = RAND_DRBG_get0_public();
712 CRYPTO_THREAD_write_lock(drbg->lock);
713 if (drbg->state == DRBG_UNINITIALISED)
716 for ( ; count > 0; count -= chunk, out += chunk) {
718 if (chunk > drbg->max_request)
719 chunk = drbg->max_request;
720 ret = RAND_DRBG_generate(drbg, out, chunk, 0, NULL, 0);
727 CRYPTO_THREAD_unlock(drbg->lock);
731 /* Implements the default OpenSSL RAND_add() method */
732 static int drbg_add(const void *buf, int num, double randomness)
735 RAND_DRBG *drbg = RAND_DRBG_get0_master();
740 if (num < 0 || randomness < 0.0)
743 if (randomness > (double)drbg->max_entropylen) {
745 * The purpose of this check is to bound |randomness| by a
746 * relatively small value in order to prevent an integer
747 * overflow when multiplying by 8 in the rand_drbg_restart()
753 CRYPTO_THREAD_write_lock(drbg->lock);
754 ret = rand_drbg_restart(drbg, buf,
755 (size_t)(unsigned int)num,
756 (size_t)(8*randomness));
757 CRYPTO_THREAD_unlock(drbg->lock);
762 /* Implements the default OpenSSL RAND_seed() method */
763 static int drbg_seed(const void *buf, int num)
765 return drbg_add(buf, num, num);
768 /* Implements the default OpenSSL RAND_status() method */
769 static int drbg_status(void)
772 RAND_DRBG *drbg = RAND_DRBG_get0_master();
777 CRYPTO_THREAD_write_lock(drbg->lock);
778 ret = drbg->state == DRBG_READY ? 1 : 0;
779 CRYPTO_THREAD_unlock(drbg->lock);
784 * Get the master DRBG.
785 * Returns pointer to the DRBG on success, NULL on failure.
788 RAND_DRBG *RAND_DRBG_get0_master(void)
790 if (!RUN_ONCE(&rand_drbg_init, do_rand_drbg_init))
797 * Get the public DRBG.
798 * Returns pointer to the DRBG on success, NULL on failure.
800 RAND_DRBG *RAND_DRBG_get0_public(void)
802 if (!RUN_ONCE(&rand_drbg_init, do_rand_drbg_init))
809 * Get the private DRBG.
810 * Returns pointer to the DRBG on success, NULL on failure.
812 RAND_DRBG *RAND_DRBG_get0_private(void)
814 if (!RUN_ONCE(&rand_drbg_init, do_rand_drbg_init))
817 return &drbg_private;
820 RAND_METHOD rand_meth = {
829 RAND_METHOD *RAND_OpenSSL(void)