2 * Copyright 2011-2018 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 RAND_DRBG *drbg_setup(const char *name, RAND_DRBG *parent);
102 static void drbg_cleanup(RAND_DRBG *drbg);
105 * Set/initialize |drbg| to be of type |nid|, with optional |flags|.
107 * Returns 1 on success, 0 on failure.
109 int RAND_DRBG_set(RAND_DRBG *drbg, int nid, unsigned int flags)
113 drbg->state = DRBG_UNINITIALISED;
119 RANDerr(RAND_F_RAND_DRBG_SET, RAND_R_UNSUPPORTED_DRBG_TYPE);
122 /* Uninitialized; that's okay. */
124 case NID_aes_128_ctr:
125 case NID_aes_192_ctr:
126 case NID_aes_256_ctr:
127 ret = drbg_ctr_init(drbg);
132 RANDerr(RAND_F_RAND_DRBG_SET, RAND_R_ERROR_INITIALISING_DRBG);
137 * Allocate memory and initialize a new DRBG. The |parent|, if not
138 * NULL, will be used to auto-seed this RAND_DRBG as needed.
140 * Returns a pointer to the new DRBG instance on success, NULL on failure.
142 RAND_DRBG *RAND_DRBG_new(int type, unsigned int flags, RAND_DRBG *parent)
144 RAND_DRBG *drbg = OPENSSL_zalloc(sizeof(*drbg));
147 RANDerr(RAND_F_RAND_DRBG_NEW, ERR_R_MALLOC_FAILURE);
150 drbg->fork_count = rand_fork_count;
151 drbg->parent = parent;
152 if (RAND_DRBG_set(drbg, type, flags) == 0)
155 if (!RAND_DRBG_set_callbacks(drbg, rand_drbg_get_entropy,
156 rand_drbg_cleanup_entropy,
168 * Uninstantiate |drbg| and free all memory.
170 void RAND_DRBG_free(RAND_DRBG *drbg)
175 if (drbg->meth != NULL)
176 drbg->meth->uninstantiate(drbg);
177 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DRBG, drbg, &drbg->ex_data);
178 OPENSSL_clear_free(drbg, sizeof(*drbg));
182 * Instantiate |drbg|, after it has been initialized. Use |pers| and
183 * |perslen| as prediction-resistance input.
185 * Requires that drbg->lock is already locked for write, if non-null.
187 * Returns 1 on success, 0 on failure.
189 int RAND_DRBG_instantiate(RAND_DRBG *drbg,
190 const unsigned char *pers, size_t perslen)
192 unsigned char *nonce = NULL, *entropy = NULL;
193 size_t noncelen = 0, entropylen = 0;
195 if (perslen > drbg->max_perslen) {
196 RANDerr(RAND_F_RAND_DRBG_INSTANTIATE,
197 RAND_R_PERSONALISATION_STRING_TOO_LONG);
201 if (drbg->meth == NULL)
203 RANDerr(RAND_F_RAND_DRBG_INSTANTIATE,
204 RAND_R_NO_DRBG_IMPLEMENTATION_SELECTED);
208 if (drbg->state != DRBG_UNINITIALISED) {
209 RANDerr(RAND_F_RAND_DRBG_INSTANTIATE,
210 drbg->state == DRBG_ERROR ? RAND_R_IN_ERROR_STATE
211 : RAND_R_ALREADY_INSTANTIATED);
215 drbg->state = DRBG_ERROR;
216 if (drbg->get_entropy != NULL)
217 entropylen = drbg->get_entropy(drbg, &entropy, drbg->strength,
218 drbg->min_entropylen, drbg->max_entropylen);
219 if (entropylen < drbg->min_entropylen
220 || entropylen > drbg->max_entropylen) {
221 RANDerr(RAND_F_RAND_DRBG_INSTANTIATE, RAND_R_ERROR_RETRIEVING_ENTROPY);
225 if (drbg->max_noncelen > 0 && drbg->get_nonce != NULL) {
226 noncelen = drbg->get_nonce(drbg, &nonce, drbg->strength / 2,
227 drbg->min_noncelen, drbg->max_noncelen);
228 if (noncelen < drbg->min_noncelen || noncelen > drbg->max_noncelen) {
229 RANDerr(RAND_F_RAND_DRBG_INSTANTIATE,
230 RAND_R_ERROR_RETRIEVING_NONCE);
235 if (!drbg->meth->instantiate(drbg, entropy, entropylen,
236 nonce, noncelen, pers, perslen)) {
237 RANDerr(RAND_F_RAND_DRBG_INSTANTIATE, RAND_R_ERROR_INSTANTIATING_DRBG);
241 drbg->state = DRBG_READY;
242 drbg->generate_counter = 0;
243 drbg->reseed_time = time(NULL);
244 if (drbg->reseed_counter > 0) {
245 if (drbg->parent == NULL)
246 drbg->reseed_counter++;
248 drbg->reseed_counter = drbg->parent->reseed_counter;
252 if (entropy != NULL && drbg->cleanup_entropy != NULL)
253 drbg->cleanup_entropy(drbg, entropy, entropylen);
254 if (nonce != NULL && drbg->cleanup_nonce!= NULL )
255 drbg->cleanup_nonce(drbg, nonce, noncelen);
256 if (drbg->pool != NULL) {
257 if (drbg->state == DRBG_READY) {
258 RANDerr(RAND_F_RAND_DRBG_INSTANTIATE,
259 RAND_R_ERROR_ENTROPY_POOL_WAS_IGNORED);
260 drbg->state = DRBG_ERROR;
262 RAND_POOL_free(drbg->pool);
265 if (drbg->state == DRBG_READY)
271 * Uninstantiate |drbg|. Must be instantiated before it can be used.
273 * Requires that drbg->lock is already locked for write, if non-null.
275 * Returns 1 on success, 0 on failure.
277 int RAND_DRBG_uninstantiate(RAND_DRBG *drbg)
279 if (drbg->meth == NULL)
281 RANDerr(RAND_F_RAND_DRBG_UNINSTANTIATE,
282 RAND_R_NO_DRBG_IMPLEMENTATION_SELECTED);
286 /* Clear the entire drbg->ctr struct, then reset some important
287 * members of the drbg->ctr struct (e.g. keysize, df_ks) to their
290 drbg->meth->uninstantiate(drbg);
291 return RAND_DRBG_set(drbg, drbg->nid, drbg->flags);
295 * Reseed |drbg|, mixing in the specified data
297 * Requires that drbg->lock is already locked for write, if non-null.
299 * Returns 1 on success, 0 on failure.
301 int RAND_DRBG_reseed(RAND_DRBG *drbg,
302 const unsigned char *adin, size_t adinlen)
304 unsigned char *entropy = NULL;
305 size_t entropylen = 0;
307 if (drbg->state == DRBG_ERROR) {
308 RANDerr(RAND_F_RAND_DRBG_RESEED, RAND_R_IN_ERROR_STATE);
311 if (drbg->state == DRBG_UNINITIALISED) {
312 RANDerr(RAND_F_RAND_DRBG_RESEED, RAND_R_NOT_INSTANTIATED);
318 else if (adinlen > drbg->max_adinlen) {
319 RANDerr(RAND_F_RAND_DRBG_RESEED, RAND_R_ADDITIONAL_INPUT_TOO_LONG);
323 drbg->state = DRBG_ERROR;
324 if (drbg->get_entropy != NULL)
325 entropylen = drbg->get_entropy(drbg, &entropy, drbg->strength,
326 drbg->min_entropylen, drbg->max_entropylen);
327 if (entropylen < drbg->min_entropylen
328 || entropylen > drbg->max_entropylen) {
329 RANDerr(RAND_F_RAND_DRBG_RESEED, RAND_R_ERROR_RETRIEVING_ENTROPY);
333 if (!drbg->meth->reseed(drbg, entropy, entropylen, adin, adinlen))
336 drbg->state = DRBG_READY;
337 drbg->generate_counter = 0;
338 drbg->reseed_time = time(NULL);
339 if (drbg->reseed_counter > 0) {
340 if (drbg->parent == NULL)
341 drbg->reseed_counter++;
343 drbg->reseed_counter = drbg->parent->reseed_counter;
347 if (entropy != NULL && drbg->cleanup_entropy != NULL)
348 drbg->cleanup_entropy(drbg, entropy, entropylen);
349 if (drbg->state == DRBG_READY)
355 * Restart |drbg|, using the specified entropy or additional input
357 * Tries its best to get the drbg instantiated by all means,
358 * regardless of its current state.
360 * Optionally, a |buffer| of |len| random bytes can be passed,
361 * which is assumed to contain at least |entropy| bits of entropy.
363 * If |entropy| > 0, the buffer content is used as entropy input.
365 * If |entropy| == 0, the buffer content is used as additional input
367 * Returns 1 on success, 0 on failure.
369 * This function is used internally only.
371 int rand_drbg_restart(RAND_DRBG *drbg,
372 const unsigned char *buffer, size_t len, size_t entropy)
375 const unsigned char *adin = NULL;
378 if (drbg->pool != NULL) {
379 RANDerr(RAND_F_RAND_DRBG_RESTART, ERR_R_INTERNAL_ERROR);
380 RAND_POOL_free(drbg->pool);
384 if (buffer != NULL) {
386 if (drbg->max_entropylen < len) {
387 RANDerr(RAND_F_RAND_DRBG_RESTART,
388 RAND_R_ENTROPY_INPUT_TOO_LONG);
392 if (entropy > 8 * len) {
393 RANDerr(RAND_F_RAND_DRBG_RESTART, RAND_R_ENTROPY_OUT_OF_RANGE);
397 /* will be picked up by the rand_drbg_get_entropy() callback */
398 drbg->pool = RAND_POOL_new(entropy, len, len);
399 if (drbg->pool == NULL)
402 RAND_POOL_add(drbg->pool, buffer, len, entropy);
404 if (drbg->max_adinlen < len) {
405 RANDerr(RAND_F_RAND_DRBG_RESTART,
406 RAND_R_ADDITIONAL_INPUT_TOO_LONG);
414 /* repair error state */
415 if (drbg->state == DRBG_ERROR)
416 RAND_DRBG_uninstantiate(drbg);
418 /* repair uninitialized state */
419 if (drbg->state == DRBG_UNINITIALISED) {
420 /* reinstantiate drbg */
421 RAND_DRBG_instantiate(drbg,
422 (const unsigned char *) ossl_pers_string,
423 sizeof(ossl_pers_string) - 1);
424 /* already reseeded. prevent second reseeding below */
425 reseeded = (drbg->state == DRBG_READY);
428 /* refresh current state if entropy or additional input has been provided */
429 if (drbg->state == DRBG_READY) {
432 * mix in additional input without reseeding
434 * Similar to RAND_DRBG_reseed(), but the provided additional
435 * data |adin| is mixed into the current state without pulling
436 * entropy from the trusted entropy source using get_entropy().
437 * This is not a reseeding in the strict sense of NIST SP 800-90A.
439 drbg->meth->reseed(drbg, adin, adinlen, NULL, 0);
440 } else if (reseeded == 0) {
441 /* do a full reseeding if it has not been done yet above */
442 RAND_DRBG_reseed(drbg, NULL, 0);
446 /* check whether a given entropy pool was cleared properly during reseed */
447 if (drbg->pool != NULL) {
448 drbg->state = DRBG_ERROR;
449 RANDerr(RAND_F_RAND_DRBG_RESTART, ERR_R_INTERNAL_ERROR);
450 RAND_POOL_free(drbg->pool);
455 return drbg->state == DRBG_READY;
459 * Generate |outlen| bytes into the buffer at |out|. Reseed if we need
460 * to or if |prediction_resistance| is set. Additional input can be
461 * sent in |adin| and |adinlen|.
463 * Requires that drbg->lock is already locked for write, if non-null.
465 * Returns 1 on success, 0 on failure.
468 int RAND_DRBG_generate(RAND_DRBG *drbg, unsigned char *out, size_t outlen,
469 int prediction_resistance,
470 const unsigned char *adin, size_t adinlen)
472 int reseed_required = 0;
474 if (drbg->state != DRBG_READY) {
475 /* try to recover from previous errors */
476 rand_drbg_restart(drbg, NULL, 0, 0);
478 if (drbg->state == DRBG_ERROR) {
479 RANDerr(RAND_F_RAND_DRBG_GENERATE, RAND_R_IN_ERROR_STATE);
482 if (drbg->state == DRBG_UNINITIALISED) {
483 RANDerr(RAND_F_RAND_DRBG_GENERATE, RAND_R_NOT_INSTANTIATED);
488 if (outlen > drbg->max_request) {
489 RANDerr(RAND_F_RAND_DRBG_GENERATE, RAND_R_REQUEST_TOO_LARGE_FOR_DRBG);
492 if (adinlen > drbg->max_adinlen) {
493 RANDerr(RAND_F_RAND_DRBG_GENERATE, RAND_R_ADDITIONAL_INPUT_TOO_LONG);
497 if (drbg->fork_count != rand_fork_count) {
498 drbg->fork_count = rand_fork_count;
502 if (drbg->reseed_interval > 0) {
503 if (drbg->generate_counter >= drbg->reseed_interval)
506 if (drbg->reseed_time_interval > 0) {
507 time_t now = time(NULL);
508 if (now < drbg->reseed_time
509 || now - drbg->reseed_time >= drbg->reseed_time_interval)
512 if (drbg->reseed_counter > 0 && drbg->parent != NULL) {
513 if (drbg->reseed_counter != drbg->parent->reseed_counter)
517 if (reseed_required || prediction_resistance) {
518 if (!RAND_DRBG_reseed(drbg, adin, adinlen)) {
519 RANDerr(RAND_F_RAND_DRBG_GENERATE, RAND_R_RESEED_ERROR);
526 if (!drbg->meth->generate(drbg, out, outlen, adin, adinlen)) {
527 drbg->state = DRBG_ERROR;
528 RANDerr(RAND_F_RAND_DRBG_GENERATE, RAND_R_GENERATE_ERROR);
532 drbg->generate_counter++;
538 * Set the RAND_DRBG callbacks for obtaining entropy and nonce.
540 * In the following, the signature and the semantics of the
541 * get_entropy() and cleanup_entropy() callbacks are explained.
545 * size_t get_entropy(RAND_DRBG *ctx,
546 * unsigned char **pout,
548 * size_t min_len, size_t max_len);
550 * This is a request to allocate and fill a buffer of size
551 * |min_len| <= size <= |max_len| (in bytes) which contains
552 * at least |entropy| bits of randomness. The buffer's address is
553 * to be returned in |*pout| and the number of collected
554 * randomness bytes (which may be less than the allocated size
555 * of the buffer) as return value.
557 * If the callback fails to acquire at least |entropy| bits of
558 * randomness, it shall return a buffer length of 0.
562 * void cleanup_entropy(RAND_DRBG *ctx,
563 * unsigned char *out, size_t outlen);
565 * A request to clear and free the buffer allocated by get_entropy().
566 * The values |out| and |outlen| are expected to be the random buffer's
567 * address and length, as returned by the get_entropy() callback.
569 * GET_NONCE, CLEANUP_NONCE
571 * Signature and semantics of the get_nonce() and cleanup_nonce()
572 * callbacks are analogous to get_entropy() and cleanup_entropy().
573 * Currently, the nonce is used only for the known answer tests.
575 int RAND_DRBG_set_callbacks(RAND_DRBG *drbg,
576 RAND_DRBG_get_entropy_fn get_entropy,
577 RAND_DRBG_cleanup_entropy_fn cleanup_entropy,
578 RAND_DRBG_get_nonce_fn get_nonce,
579 RAND_DRBG_cleanup_nonce_fn cleanup_nonce)
581 if (drbg->state != DRBG_UNINITIALISED)
583 drbg->get_entropy = get_entropy;
584 drbg->cleanup_entropy = cleanup_entropy;
585 drbg->get_nonce = get_nonce;
586 drbg->cleanup_nonce = cleanup_nonce;
591 * Set the reseed interval.
593 * The drbg will reseed automatically whenever the number of generate
594 * requests exceeds the given reseed interval. If the reseed interval
595 * is 0, then this feature is disabled.
597 * Returns 1 on success, 0 on failure.
599 int RAND_DRBG_set_reseed_interval(RAND_DRBG *drbg, unsigned int interval)
601 if (interval > MAX_RESEED_INTERVAL)
603 drbg->reseed_interval = interval;
608 * Set the reseed time interval.
610 * The drbg will reseed automatically whenever the time elapsed since
611 * the last reseeding exceeds the given reseed time interval. For safety,
612 * a reseeding will also occur if the clock has been reset to a smaller
615 * Returns 1 on success, 0 on failure.
617 int RAND_DRBG_set_reseed_time_interval(RAND_DRBG *drbg, time_t interval)
619 if (interval > MAX_RESEED_TIME_INTERVAL)
621 drbg->reseed_time_interval = interval;
626 * Get and set the EXDATA
628 int RAND_DRBG_set_ex_data(RAND_DRBG *drbg, int idx, void *arg)
630 return CRYPTO_set_ex_data(&drbg->ex_data, idx, arg);
633 void *RAND_DRBG_get_ex_data(const RAND_DRBG *drbg, int idx)
635 return CRYPTO_get_ex_data(&drbg->ex_data, idx);
640 * The following functions provide a RAND_METHOD that works on the
641 * global DRBG. They lock.
645 * Allocates a new global DRBG on the secure heap (if enabled) and
646 * initializes it with default settings.
647 * A global lock for the DRBG is created with the given name.
649 * Returns a pointer to the new DRBG instance on success, NULL on failure.
651 static RAND_DRBG *drbg_setup(const char *name, RAND_DRBG *parent)
656 RANDerr(RAND_F_DRBG_SETUP, ERR_R_INTERNAL_ERROR);
660 drbg = OPENSSL_secure_zalloc(sizeof(RAND_DRBG));
664 drbg->lock = CRYPTO_THREAD_glock_new(name);
665 if (drbg->lock == NULL) {
666 RANDerr(RAND_F_DRBG_SETUP, RAND_R_FAILED_TO_CREATE_LOCK);
670 if (RAND_DRBG_set(drbg,
671 RAND_DRBG_NID, RAND_DRBG_FLAG_CTR_USE_DF) != 1)
673 if (RAND_DRBG_set_callbacks(drbg, rand_drbg_get_entropy,
674 rand_drbg_cleanup_entropy, NULL, NULL) != 1)
677 if (parent == NULL) {
678 drbg->reseed_interval = MASTER_RESEED_INTERVAL;
679 drbg->reseed_time_interval = MASTER_RESEED_TIME_INTERVAL;
681 drbg->parent = parent;
682 drbg->reseed_interval = SLAVE_RESEED_INTERVAL;
683 drbg->reseed_time_interval = SLAVE_RESEED_TIME_INTERVAL;
686 /* enable seed propagation */
687 drbg->reseed_counter = 1;
690 * Ignore instantiation error so support just-in-time instantiation.
692 * The state of the drbg will be checked in RAND_DRBG_generate() and
693 * an automatic recovery is attempted.
695 RAND_DRBG_instantiate(drbg,
696 (const unsigned char *) ossl_pers_string,
697 sizeof(ossl_pers_string) - 1);
706 * Initialize the global DRBGs on first use.
707 * Returns 1 on success, 0 on failure.
709 DEFINE_RUN_ONCE_STATIC(do_rand_drbg_init)
712 * ensure that libcrypto is initialized, otherwise the
713 * DRBG locks are not cleaned up properly
715 if (!OPENSSL_init_crypto(0, NULL))
718 drbg_master = drbg_setup("drbg_master", NULL);
719 drbg_public = drbg_setup("drbg_public", drbg_master);
720 drbg_private = drbg_setup("drbg_private", drbg_master);
722 if (drbg_master == NULL || drbg_public == NULL || drbg_private == NULL)
728 /* Cleans up the given global DRBG */
729 static void drbg_cleanup(RAND_DRBG *drbg)
732 RAND_DRBG_uninstantiate(drbg);
733 CRYPTO_THREAD_lock_free(drbg->lock);
734 OPENSSL_secure_clear_free(drbg, sizeof(RAND_DRBG));
738 /* Clean up the global DRBGs before exit */
739 void rand_drbg_cleanup_int(void)
741 drbg_cleanup(drbg_private);
742 drbg_cleanup(drbg_public);
743 drbg_cleanup(drbg_master);
745 drbg_private = drbg_public = drbg_master = NULL;
748 /* Implements the default OpenSSL RAND_bytes() method */
749 static int drbg_bytes(unsigned char *out, int count)
753 RAND_DRBG *drbg = RAND_DRBG_get0_public();
758 CRYPTO_THREAD_write_lock(drbg->lock);
759 if (drbg->state == DRBG_UNINITIALISED)
762 for ( ; count > 0; count -= chunk, out += chunk) {
764 if (chunk > drbg->max_request)
765 chunk = drbg->max_request;
766 ret = RAND_DRBG_generate(drbg, out, chunk, 0, NULL, 0);
773 CRYPTO_THREAD_unlock(drbg->lock);
777 /* Implements the default OpenSSL RAND_add() method */
778 static int drbg_add(const void *buf, int num, double randomness)
781 RAND_DRBG *drbg = RAND_DRBG_get0_master();
786 if (num < 0 || randomness < 0.0)
789 if (randomness > (double)drbg->max_entropylen) {
791 * The purpose of this check is to bound |randomness| by a
792 * relatively small value in order to prevent an integer
793 * overflow when multiplying by 8 in the rand_drbg_restart()
799 CRYPTO_THREAD_write_lock(drbg->lock);
800 ret = rand_drbg_restart(drbg, buf,
801 (size_t)(unsigned int)num,
802 (size_t)(8*randomness));
803 CRYPTO_THREAD_unlock(drbg->lock);
808 /* Implements the default OpenSSL RAND_seed() method */
809 static int drbg_seed(const void *buf, int num)
811 return drbg_add(buf, num, num);
814 /* Implements the default OpenSSL RAND_status() method */
815 static int drbg_status(void)
818 RAND_DRBG *drbg = RAND_DRBG_get0_master();
823 CRYPTO_THREAD_write_lock(drbg->lock);
824 ret = drbg->state == DRBG_READY ? 1 : 0;
825 CRYPTO_THREAD_unlock(drbg->lock);
830 * Get the master DRBG.
831 * Returns pointer to the DRBG on success, NULL on failure.
834 RAND_DRBG *RAND_DRBG_get0_master(void)
836 if (!RUN_ONCE(&rand_drbg_init, do_rand_drbg_init))
843 * Get the public DRBG.
844 * Returns pointer to the DRBG on success, NULL on failure.
846 RAND_DRBG *RAND_DRBG_get0_public(void)
848 if (!RUN_ONCE(&rand_drbg_init, do_rand_drbg_init))
855 * Get the private DRBG.
856 * Returns pointer to the DRBG on success, NULL on failure.
858 RAND_DRBG *RAND_DRBG_get0_private(void)
860 if (!RUN_ONCE(&rand_drbg_init, do_rand_drbg_init))
866 RAND_METHOD rand_meth = {
875 RAND_METHOD *RAND_OpenSSL(void)