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"
17 #include "internal/cryptlib_int.h"
20 * Support framework for NIST SP 800-90A DRBG
22 * See manual page RAND_DRBG(7) for a general overview.
24 * The OpenSSL model is to have new and free functions, and that new
25 * does all initialization. That is not the NIST model, which has
26 * instantiation and un-instantiate, and re-use within a new/free
27 * lifecycle. (No doubt this comes from the desire to support hardware
28 * DRBG, where allocation of resources on something like an HSM is
29 * a much bigger deal than just re-setting an allocated resource.)
33 * The three shared DRBG instances
35 * There are three shared DRBG instances: <master>, <public>, and <private>.
41 * Not used directly by the application, only for reseeding the two other
42 * DRBGs. It reseeds itself by pulling either randomness from os entropy
43 * sources or by consuming randomness which was added by RAND_add().
45 * The <master> DRBG is a global instance which is accessed concurrently by
46 * all threads. The necessary locking is managed automatically by its child
47 * DRBG instances during reseeding.
49 static RAND_DRBG
*master_drbg
;
53 * Used by default for generating random bytes using RAND_bytes().
55 * The <public> DRBG is thread-local, i.e., there is one instance per thread.
57 static CRYPTO_THREAD_LOCAL public_drbg
;
61 * Used by default for generating private keys using RAND_priv_bytes()
63 * The <private> DRBG is thread-local, i.e., there is one instance per thread.
65 static CRYPTO_THREAD_LOCAL private_drbg
;
69 /* NIST SP 800-90A DRBG recommends the use of a personalization string. */
70 static const char ossl_pers_string
[] = "OpenSSL NIST SP 800-90A DRBG";
72 static CRYPTO_ONCE rand_drbg_init
= CRYPTO_ONCE_STATIC_INIT
;
76 static int rand_drbg_type
= RAND_DRBG_TYPE
;
77 static unsigned int rand_drbg_flags
= RAND_DRBG_FLAGS
;
79 static unsigned int master_reseed_interval
= MASTER_RESEED_INTERVAL
;
80 static unsigned int slave_reseed_interval
= SLAVE_RESEED_INTERVAL
;
82 static time_t master_reseed_time_interval
= MASTER_RESEED_TIME_INTERVAL
;
83 static time_t slave_reseed_time_interval
= SLAVE_RESEED_TIME_INTERVAL
;
85 static RAND_DRBG
*drbg_setup(RAND_DRBG
*parent
);
87 static RAND_DRBG
*rand_drbg_new(int secure
,
93 * Set/initialize |drbg| to be of type |type|, with optional |flags|.
95 * If |type| and |flags| are zero, use the defaults
97 * Returns 1 on success, 0 on failure.
99 int RAND_DRBG_set(RAND_DRBG
*drbg
, int type
, unsigned int flags
)
103 if (type
== 0 && flags
== 0) {
104 type
= rand_drbg_type
;
105 flags
= rand_drbg_flags
;
108 drbg
->state
= DRBG_UNINITIALISED
;
114 RANDerr(RAND_F_RAND_DRBG_SET
, RAND_R_UNSUPPORTED_DRBG_TYPE
);
117 /* Uninitialized; that's okay. */
119 case NID_aes_128_ctr
:
120 case NID_aes_192_ctr
:
121 case NID_aes_256_ctr
:
122 ret
= drbg_ctr_init(drbg
);
127 RANDerr(RAND_F_RAND_DRBG_SET
, RAND_R_ERROR_INITIALISING_DRBG
);
132 * Set/initialize default |type| and |flag| for new drbg instances.
134 * Returns 1 on success, 0 on failure.
136 int RAND_DRBG_set_defaults(int type
, unsigned int flags
)
142 RANDerr(RAND_F_RAND_DRBG_SET_DEFAULTS
, RAND_R_UNSUPPORTED_DRBG_TYPE
);
144 case NID_aes_128_ctr
:
145 case NID_aes_192_ctr
:
146 case NID_aes_256_ctr
:
150 if ((flags
& ~RAND_DRBG_USED_FLAGS
) != 0) {
151 RANDerr(RAND_F_RAND_DRBG_SET_DEFAULTS
, RAND_R_UNSUPPORTED_DRBG_FLAGS
);
155 rand_drbg_type
= type
;
156 rand_drbg_flags
= flags
;
163 * Allocate memory and initialize a new DRBG. The DRBG is allocated on
164 * the secure heap if |secure| is nonzero and the secure heap is enabled.
165 * The |parent|, if not NULL, will be used as random source for reseeding.
167 * Returns a pointer to the new DRBG instance on success, NULL on failure.
169 static RAND_DRBG
*rand_drbg_new(int secure
,
174 RAND_DRBG
*drbg
= secure
?
175 OPENSSL_secure_zalloc(sizeof(*drbg
)) : OPENSSL_zalloc(sizeof(*drbg
));
178 RANDerr(RAND_F_RAND_DRBG_NEW
, ERR_R_MALLOC_FAILURE
);
182 drbg
->secure
= secure
&& CRYPTO_secure_allocated(drbg
);
183 drbg
->fork_count
= rand_fork_count
;
184 drbg
->parent
= parent
;
186 if (parent
== NULL
) {
187 drbg
->get_entropy
= rand_drbg_get_entropy
;
188 drbg
->cleanup_entropy
= rand_drbg_cleanup_entropy
;
189 #ifndef RAND_DRBG_GET_RANDOM_NONCE
190 drbg
->get_nonce
= rand_drbg_get_nonce
;
191 drbg
->cleanup_nonce
= rand_drbg_cleanup_nonce
;
194 drbg
->reseed_interval
= master_reseed_interval
;
195 drbg
->reseed_time_interval
= master_reseed_time_interval
;
197 drbg
->get_entropy
= rand_drbg_get_entropy
;
198 drbg
->cleanup_entropy
= rand_drbg_cleanup_entropy
;
200 * Do not provide nonce callbacks, the child DRBGs will
201 * obtain their nonce using random bits from the parent.
204 drbg
->reseed_interval
= slave_reseed_interval
;
205 drbg
->reseed_time_interval
= slave_reseed_time_interval
;
208 if (RAND_DRBG_set(drbg
, type
, flags
) == 0)
211 if (parent
!= NULL
) {
212 rand_drbg_lock(parent
);
213 if (drbg
->strength
> parent
->strength
) {
215 * We currently don't support the algorithm from NIST SP 800-90C
216 * 10.1.2 to use a weaker DRBG as source
218 rand_drbg_unlock(parent
);
219 RANDerr(RAND_F_RAND_DRBG_NEW
, RAND_R_PARENT_STRENGTH_TOO_WEAK
);
222 rand_drbg_unlock(parent
);
229 OPENSSL_secure_free(drbg
);
236 RAND_DRBG
*RAND_DRBG_new(int type
, unsigned int flags
, RAND_DRBG
*parent
)
238 return rand_drbg_new(0, type
, flags
, parent
);
241 RAND_DRBG
*RAND_DRBG_secure_new(int type
, unsigned int flags
, RAND_DRBG
*parent
)
243 return rand_drbg_new(1, type
, flags
, parent
);
247 * Uninstantiate |drbg| and free all memory.
249 void RAND_DRBG_free(RAND_DRBG
*drbg
)
254 if (drbg
->meth
!= NULL
)
255 drbg
->meth
->uninstantiate(drbg
);
256 CRYPTO_THREAD_lock_free(drbg
->lock
);
257 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DRBG
, drbg
, &drbg
->ex_data
);
260 OPENSSL_secure_clear_free(drbg
, sizeof(*drbg
));
262 OPENSSL_clear_free(drbg
, sizeof(*drbg
));
266 * Instantiate |drbg|, after it has been initialized. Use |pers| and
267 * |perslen| as prediction-resistance input.
269 * Requires that drbg->lock is already locked for write, if non-null.
271 * Returns 1 on success, 0 on failure.
273 int RAND_DRBG_instantiate(RAND_DRBG
*drbg
,
274 const unsigned char *pers
, size_t perslen
)
276 unsigned char *nonce
= NULL
, *entropy
= NULL
;
277 size_t noncelen
= 0, entropylen
= 0;
278 size_t min_entropy
= drbg
->strength
;
279 size_t min_entropylen
= drbg
->min_entropylen
;
280 size_t max_entropylen
= drbg
->max_entropylen
;
282 if (perslen
> drbg
->max_perslen
) {
283 RANDerr(RAND_F_RAND_DRBG_INSTANTIATE
,
284 RAND_R_PERSONALISATION_STRING_TOO_LONG
);
288 if (drbg
->meth
== NULL
) {
289 RANDerr(RAND_F_RAND_DRBG_INSTANTIATE
,
290 RAND_R_NO_DRBG_IMPLEMENTATION_SELECTED
);
294 if (drbg
->state
!= DRBG_UNINITIALISED
) {
295 RANDerr(RAND_F_RAND_DRBG_INSTANTIATE
,
296 drbg
->state
== DRBG_ERROR
? RAND_R_IN_ERROR_STATE
297 : RAND_R_ALREADY_INSTANTIATED
);
301 drbg
->state
= DRBG_ERROR
;
304 * NIST SP800-90Ar1 section 9.1 says you can combine getting the entropy
305 * and nonce in 1 call by increasing the entropy with 50% and increasing
306 * the minimum length to accomadate the length of the nonce.
307 * We do this in case a nonce is require and get_nonce is NULL.
309 if (drbg
->min_noncelen
> 0 && drbg
->get_nonce
== NULL
) {
310 min_entropy
+= drbg
->strength
/ 2;
311 min_entropylen
+= drbg
->min_noncelen
;
312 max_entropylen
+= drbg
->max_noncelen
;
315 if (drbg
->get_entropy
!= NULL
)
316 entropylen
= drbg
->get_entropy(drbg
, &entropy
, min_entropy
,
317 min_entropylen
, max_entropylen
, 0);
318 if (entropylen
< min_entropylen
319 || entropylen
> max_entropylen
) {
320 RANDerr(RAND_F_RAND_DRBG_INSTANTIATE
, RAND_R_ERROR_RETRIEVING_ENTROPY
);
324 if (drbg
->min_noncelen
> 0 && drbg
->get_nonce
!= NULL
) {
325 noncelen
= drbg
->get_nonce(drbg
, &nonce
, drbg
->strength
/ 2,
326 drbg
->min_noncelen
, drbg
->max_noncelen
);
327 if (noncelen
< drbg
->min_noncelen
|| noncelen
> drbg
->max_noncelen
) {
328 RANDerr(RAND_F_RAND_DRBG_INSTANTIATE
, RAND_R_ERROR_RETRIEVING_NONCE
);
333 if (!drbg
->meth
->instantiate(drbg
, entropy
, entropylen
,
334 nonce
, noncelen
, pers
, perslen
)) {
335 RANDerr(RAND_F_RAND_DRBG_INSTANTIATE
, RAND_R_ERROR_INSTANTIATING_DRBG
);
339 drbg
->state
= DRBG_READY
;
340 drbg
->generate_counter
= 0;
341 drbg
->reseed_time
= time(NULL
);
342 if (drbg
->reseed_counter
> 0) {
343 if (drbg
->parent
== NULL
)
344 drbg
->reseed_counter
++;
346 drbg
->reseed_counter
= drbg
->parent
->reseed_counter
;
350 if (entropy
!= NULL
&& drbg
->cleanup_entropy
!= NULL
)
351 drbg
->cleanup_entropy(drbg
, entropy
, entropylen
);
352 if (nonce
!= NULL
&& drbg
->cleanup_nonce
!= NULL
)
353 drbg
->cleanup_nonce(drbg
, nonce
, noncelen
);
354 if (drbg
->pool
!= NULL
) {
355 if (drbg
->state
== DRBG_READY
) {
356 RANDerr(RAND_F_RAND_DRBG_INSTANTIATE
,
357 RAND_R_ERROR_ENTROPY_POOL_WAS_IGNORED
);
358 drbg
->state
= DRBG_ERROR
;
360 rand_pool_free(drbg
->pool
);
363 if (drbg
->state
== DRBG_READY
)
369 * Uninstantiate |drbg|. Must be instantiated before it can be used.
371 * Requires that drbg->lock is already locked for write, if non-null.
373 * Returns 1 on success, 0 on failure.
375 int RAND_DRBG_uninstantiate(RAND_DRBG
*drbg
)
377 if (drbg
->meth
== NULL
) {
378 RANDerr(RAND_F_RAND_DRBG_UNINSTANTIATE
,
379 RAND_R_NO_DRBG_IMPLEMENTATION_SELECTED
);
383 /* Clear the entire drbg->ctr struct, then reset some important
384 * members of the drbg->ctr struct (e.g. keysize, df_ks) to their
387 drbg
->meth
->uninstantiate(drbg
);
388 return RAND_DRBG_set(drbg
, drbg
->type
, drbg
->flags
);
392 * Reseed |drbg|, mixing in the specified data
394 * Requires that drbg->lock is already locked for write, if non-null.
396 * Returns 1 on success, 0 on failure.
398 int RAND_DRBG_reseed(RAND_DRBG
*drbg
,
399 const unsigned char *adin
, size_t adinlen
,
400 int prediction_resistance
)
402 unsigned char *entropy
= NULL
;
403 size_t entropylen
= 0;
405 if (drbg
->state
== DRBG_ERROR
) {
406 RANDerr(RAND_F_RAND_DRBG_RESEED
, RAND_R_IN_ERROR_STATE
);
409 if (drbg
->state
== DRBG_UNINITIALISED
) {
410 RANDerr(RAND_F_RAND_DRBG_RESEED
, RAND_R_NOT_INSTANTIATED
);
416 } else if (adinlen
> drbg
->max_adinlen
) {
417 RANDerr(RAND_F_RAND_DRBG_RESEED
, RAND_R_ADDITIONAL_INPUT_TOO_LONG
);
421 drbg
->state
= DRBG_ERROR
;
422 if (drbg
->get_entropy
!= NULL
)
423 entropylen
= drbg
->get_entropy(drbg
, &entropy
, drbg
->strength
,
424 drbg
->min_entropylen
,
425 drbg
->max_entropylen
,
426 prediction_resistance
);
427 if (entropylen
< drbg
->min_entropylen
428 || entropylen
> drbg
->max_entropylen
) {
429 RANDerr(RAND_F_RAND_DRBG_RESEED
, RAND_R_ERROR_RETRIEVING_ENTROPY
);
433 if (!drbg
->meth
->reseed(drbg
, entropy
, entropylen
, adin
, adinlen
))
436 drbg
->state
= DRBG_READY
;
437 drbg
->generate_counter
= 0;
438 drbg
->reseed_time
= time(NULL
);
439 if (drbg
->reseed_counter
> 0) {
440 if (drbg
->parent
== NULL
)
441 drbg
->reseed_counter
++;
443 drbg
->reseed_counter
= drbg
->parent
->reseed_counter
;
447 if (entropy
!= NULL
&& drbg
->cleanup_entropy
!= NULL
)
448 drbg
->cleanup_entropy(drbg
, entropy
, entropylen
);
449 if (drbg
->state
== DRBG_READY
)
455 * Restart |drbg|, using the specified entropy or additional input
457 * Tries its best to get the drbg instantiated by all means,
458 * regardless of its current state.
460 * Optionally, a |buffer| of |len| random bytes can be passed,
461 * which is assumed to contain at least |entropy| bits of entropy.
463 * If |entropy| > 0, the buffer content is used as entropy input.
465 * If |entropy| == 0, the buffer content is used as additional input
467 * Returns 1 on success, 0 on failure.
469 * This function is used internally only.
471 int rand_drbg_restart(RAND_DRBG
*drbg
,
472 const unsigned char *buffer
, size_t len
, size_t entropy
)
475 const unsigned char *adin
= NULL
;
478 if (drbg
->pool
!= NULL
) {
479 RANDerr(RAND_F_RAND_DRBG_RESTART
, ERR_R_INTERNAL_ERROR
);
480 rand_pool_free(drbg
->pool
);
484 if (buffer
!= NULL
) {
486 if (drbg
->max_entropylen
< len
) {
487 RANDerr(RAND_F_RAND_DRBG_RESTART
,
488 RAND_R_ENTROPY_INPUT_TOO_LONG
);
492 if (entropy
> 8 * len
) {
493 RANDerr(RAND_F_RAND_DRBG_RESTART
, RAND_R_ENTROPY_OUT_OF_RANGE
);
497 /* will be picked up by the rand_drbg_get_entropy() callback */
498 drbg
->pool
= rand_pool_new(entropy
, len
, len
);
499 if (drbg
->pool
== NULL
)
502 rand_pool_add(drbg
->pool
, buffer
, len
, entropy
);
504 if (drbg
->max_adinlen
< len
) {
505 RANDerr(RAND_F_RAND_DRBG_RESTART
,
506 RAND_R_ADDITIONAL_INPUT_TOO_LONG
);
514 /* repair error state */
515 if (drbg
->state
== DRBG_ERROR
)
516 RAND_DRBG_uninstantiate(drbg
);
518 /* repair uninitialized state */
519 if (drbg
->state
== DRBG_UNINITIALISED
) {
520 /* reinstantiate drbg */
521 RAND_DRBG_instantiate(drbg
,
522 (const unsigned char *) ossl_pers_string
,
523 sizeof(ossl_pers_string
) - 1);
524 /* already reseeded. prevent second reseeding below */
525 reseeded
= (drbg
->state
== DRBG_READY
);
528 /* refresh current state if entropy or additional input has been provided */
529 if (drbg
->state
== DRBG_READY
) {
532 * mix in additional input without reseeding
534 * Similar to RAND_DRBG_reseed(), but the provided additional
535 * data |adin| is mixed into the current state without pulling
536 * entropy from the trusted entropy source using get_entropy().
537 * This is not a reseeding in the strict sense of NIST SP 800-90A.
539 drbg
->meth
->reseed(drbg
, adin
, adinlen
, NULL
, 0);
540 } else if (reseeded
== 0) {
541 /* do a full reseeding if it has not been done yet above */
542 RAND_DRBG_reseed(drbg
, NULL
, 0, 0);
546 /* check whether a given entropy pool was cleared properly during reseed */
547 if (drbg
->pool
!= NULL
) {
548 drbg
->state
= DRBG_ERROR
;
549 RANDerr(RAND_F_RAND_DRBG_RESTART
, ERR_R_INTERNAL_ERROR
);
550 rand_pool_free(drbg
->pool
);
555 return drbg
->state
== DRBG_READY
;
559 * Generate |outlen| bytes into the buffer at |out|. Reseed if we need
560 * to or if |prediction_resistance| is set. Additional input can be
561 * sent in |adin| and |adinlen|.
563 * Requires that drbg->lock is already locked for write, if non-null.
565 * Returns 1 on success, 0 on failure.
568 int RAND_DRBG_generate(RAND_DRBG
*drbg
, unsigned char *out
, size_t outlen
,
569 int prediction_resistance
,
570 const unsigned char *adin
, size_t adinlen
)
572 int reseed_required
= 0;
574 if (drbg
->state
!= DRBG_READY
) {
575 /* try to recover from previous errors */
576 rand_drbg_restart(drbg
, NULL
, 0, 0);
578 if (drbg
->state
== DRBG_ERROR
) {
579 RANDerr(RAND_F_RAND_DRBG_GENERATE
, RAND_R_IN_ERROR_STATE
);
582 if (drbg
->state
== DRBG_UNINITIALISED
) {
583 RANDerr(RAND_F_RAND_DRBG_GENERATE
, RAND_R_NOT_INSTANTIATED
);
588 if (outlen
> drbg
->max_request
) {
589 RANDerr(RAND_F_RAND_DRBG_GENERATE
, RAND_R_REQUEST_TOO_LARGE_FOR_DRBG
);
592 if (adinlen
> drbg
->max_adinlen
) {
593 RANDerr(RAND_F_RAND_DRBG_GENERATE
, RAND_R_ADDITIONAL_INPUT_TOO_LONG
);
597 if (drbg
->fork_count
!= rand_fork_count
) {
598 drbg
->fork_count
= rand_fork_count
;
602 if (drbg
->reseed_interval
> 0) {
603 if (drbg
->generate_counter
>= drbg
->reseed_interval
)
606 if (drbg
->reseed_time_interval
> 0) {
607 time_t now
= time(NULL
);
608 if (now
< drbg
->reseed_time
609 || now
- drbg
->reseed_time
>= drbg
->reseed_time_interval
)
612 if (drbg
->reseed_counter
> 0 && drbg
->parent
!= NULL
) {
613 if (drbg
->reseed_counter
!= drbg
->parent
->reseed_counter
)
617 if (reseed_required
|| prediction_resistance
) {
618 if (!RAND_DRBG_reseed(drbg
, adin
, adinlen
, prediction_resistance
)) {
619 RANDerr(RAND_F_RAND_DRBG_GENERATE
, RAND_R_RESEED_ERROR
);
626 if (!drbg
->meth
->generate(drbg
, out
, outlen
, adin
, adinlen
)) {
627 drbg
->state
= DRBG_ERROR
;
628 RANDerr(RAND_F_RAND_DRBG_GENERATE
, RAND_R_GENERATE_ERROR
);
632 drbg
->generate_counter
++;
638 * Generates |outlen| random bytes and stores them in |out|. It will
639 * using the given |drbg| to generate the bytes.
641 * Requires that drbg->lock is already locked for write, if non-null.
643 * Returns 1 on success 0 on failure.
645 int RAND_DRBG_bytes(RAND_DRBG
*drbg
, unsigned char *out
, size_t outlen
)
647 unsigned char *additional
= NULL
;
648 size_t additional_len
;
652 additional_len
= rand_drbg_get_additional_data(&additional
, drbg
->max_adinlen
);
654 for ( ; outlen
> 0; outlen
-= chunk
, out
+= chunk
) {
656 if (chunk
> drbg
->max_request
)
657 chunk
= drbg
->max_request
;
658 ret
= RAND_DRBG_generate(drbg
, out
, chunk
, 0, additional
, additional_len
);
665 if (additional_len
!= 0)
666 OPENSSL_secure_clear_free(additional
, additional_len
);
672 * Set the RAND_DRBG callbacks for obtaining entropy and nonce.
674 * Setting the callbacks is allowed only if the drbg has not been
675 * initialized yet. Otherwise, the operation will fail.
677 * Returns 1 on success, 0 on failure.
679 int RAND_DRBG_set_callbacks(RAND_DRBG
*drbg
,
680 RAND_DRBG_get_entropy_fn get_entropy
,
681 RAND_DRBG_cleanup_entropy_fn cleanup_entropy
,
682 RAND_DRBG_get_nonce_fn get_nonce
,
683 RAND_DRBG_cleanup_nonce_fn cleanup_nonce
)
685 if (drbg
->state
!= DRBG_UNINITIALISED
)
687 drbg
->get_entropy
= get_entropy
;
688 drbg
->cleanup_entropy
= cleanup_entropy
;
689 drbg
->get_nonce
= get_nonce
;
690 drbg
->cleanup_nonce
= cleanup_nonce
;
695 * Set the reseed interval.
697 * The drbg will reseed automatically whenever the number of generate
698 * requests exceeds the given reseed interval. If the reseed interval
699 * is 0, then this feature is disabled.
701 * Returns 1 on success, 0 on failure.
703 int RAND_DRBG_set_reseed_interval(RAND_DRBG
*drbg
, unsigned int interval
)
705 if (interval
> MAX_RESEED_INTERVAL
)
707 drbg
->reseed_interval
= interval
;
712 * Set the reseed time interval.
714 * The drbg will reseed automatically whenever the time elapsed since
715 * the last reseeding exceeds the given reseed time interval. For safety,
716 * a reseeding will also occur if the clock has been reset to a smaller
719 * Returns 1 on success, 0 on failure.
721 int RAND_DRBG_set_reseed_time_interval(RAND_DRBG
*drbg
, time_t interval
)
723 if (interval
> MAX_RESEED_TIME_INTERVAL
)
725 drbg
->reseed_time_interval
= interval
;
730 * Set the default values for reseed (time) intervals of new DRBG instances
732 * The default values can be set independently for master DRBG instances
733 * (without a parent) and slave DRBG instances (with parent).
735 * Returns 1 on success, 0 on failure.
738 int RAND_DRBG_set_reseed_defaults(
739 unsigned int _master_reseed_interval
,
740 unsigned int _slave_reseed_interval
,
741 time_t _master_reseed_time_interval
,
742 time_t _slave_reseed_time_interval
745 if (_master_reseed_interval
> MAX_RESEED_INTERVAL
746 || _slave_reseed_interval
> MAX_RESEED_INTERVAL
)
749 if (_master_reseed_time_interval
> MAX_RESEED_TIME_INTERVAL
750 || _slave_reseed_time_interval
> MAX_RESEED_TIME_INTERVAL
)
753 master_reseed_interval
= _master_reseed_interval
;
754 slave_reseed_interval
= _slave_reseed_interval
;
756 master_reseed_time_interval
= _master_reseed_time_interval
;
757 slave_reseed_time_interval
= _slave_reseed_time_interval
;
763 * Locks the given drbg. Locking a drbg which does not have locking
764 * enabled is considered a successful no-op.
766 * Returns 1 on success, 0 on failure.
768 int rand_drbg_lock(RAND_DRBG
*drbg
)
770 if (drbg
->lock
!= NULL
)
771 return CRYPTO_THREAD_write_lock(drbg
->lock
);
777 * Unlocks the given drbg. Unlocking a drbg which does not have locking
778 * enabled is considered a successful no-op.
780 * Returns 1 on success, 0 on failure.
782 int rand_drbg_unlock(RAND_DRBG
*drbg
)
784 if (drbg
->lock
!= NULL
)
785 return CRYPTO_THREAD_unlock(drbg
->lock
);
791 * Enables locking for the given drbg
793 * Locking can only be enabled if the random generator
794 * is in the uninitialized state.
796 * Returns 1 on success, 0 on failure.
798 int rand_drbg_enable_locking(RAND_DRBG
*drbg
)
800 if (drbg
->state
!= DRBG_UNINITIALISED
) {
801 RANDerr(RAND_F_RAND_DRBG_ENABLE_LOCKING
,
802 RAND_R_DRBG_ALREADY_INITIALIZED
);
806 if (drbg
->lock
== NULL
) {
807 if (drbg
->parent
!= NULL
&& drbg
->parent
->lock
== NULL
) {
808 RANDerr(RAND_F_RAND_DRBG_ENABLE_LOCKING
,
809 RAND_R_PARENT_LOCKING_NOT_ENABLED
);
813 drbg
->lock
= CRYPTO_THREAD_lock_new();
814 if (drbg
->lock
== NULL
) {
815 RANDerr(RAND_F_RAND_DRBG_ENABLE_LOCKING
,
816 RAND_R_FAILED_TO_CREATE_LOCK
);
825 * Get and set the EXDATA
827 int RAND_DRBG_set_ex_data(RAND_DRBG
*drbg
, int idx
, void *arg
)
829 return CRYPTO_set_ex_data(&drbg
->ex_data
, idx
, arg
);
832 void *RAND_DRBG_get_ex_data(const RAND_DRBG
*drbg
, int idx
)
834 return CRYPTO_get_ex_data(&drbg
->ex_data
, idx
);
839 * The following functions provide a RAND_METHOD that works on the
840 * global DRBG. They lock.
844 * Allocates a new global DRBG on the secure heap (if enabled) and
845 * initializes it with default settings.
847 * Returns a pointer to the new DRBG instance on success, NULL on failure.
849 static RAND_DRBG
*drbg_setup(RAND_DRBG
*parent
)
853 drbg
= RAND_DRBG_secure_new(rand_drbg_type
, rand_drbg_flags
, parent
);
857 /* Only the master DRBG needs to have a lock */
858 if (parent
== NULL
&& rand_drbg_enable_locking(drbg
) == 0)
861 /* enable seed propagation */
862 drbg
->reseed_counter
= 1;
865 * Ignore instantiation error to support just-in-time instantiation.
867 * The state of the drbg will be checked in RAND_DRBG_generate() and
868 * an automatic recovery is attempted.
870 (void)RAND_DRBG_instantiate(drbg
,
871 (const unsigned char *) ossl_pers_string
,
872 sizeof(ossl_pers_string
) - 1);
876 RAND_DRBG_free(drbg
);
881 * Initialize the global DRBGs on first use.
882 * Returns 1 on success, 0 on failure.
884 DEFINE_RUN_ONCE_STATIC(do_rand_drbg_init
)
887 * ensure that libcrypto is initialized, otherwise the
888 * DRBG locks are not cleaned up properly
890 if (!OPENSSL_init_crypto(0, NULL
))
893 if (!CRYPTO_THREAD_init_local(&private_drbg
, NULL
))
896 if (!CRYPTO_THREAD_init_local(&public_drbg
, NULL
))
899 master_drbg
= drbg_setup(NULL
);
900 if (master_drbg
== NULL
)
906 CRYPTO_THREAD_cleanup_local(&public_drbg
);
908 CRYPTO_THREAD_cleanup_local(&private_drbg
);
912 /* Clean up the global DRBGs before exit */
913 void rand_drbg_cleanup_int(void)
915 if (master_drbg
!= NULL
) {
916 RAND_DRBG_free(master_drbg
);
919 CRYPTO_THREAD_cleanup_local(&private_drbg
);
920 CRYPTO_THREAD_cleanup_local(&public_drbg
);
924 void drbg_delete_thread_state()
928 drbg
= CRYPTO_THREAD_get_local(&public_drbg
);
929 CRYPTO_THREAD_set_local(&public_drbg
, NULL
);
930 RAND_DRBG_free(drbg
);
932 drbg
= CRYPTO_THREAD_get_local(&private_drbg
);
933 CRYPTO_THREAD_set_local(&private_drbg
, NULL
);
934 RAND_DRBG_free(drbg
);
937 /* Implements the default OpenSSL RAND_bytes() method */
938 static int drbg_bytes(unsigned char *out
, int count
)
941 RAND_DRBG
*drbg
= RAND_DRBG_get0_public();
946 ret
= RAND_DRBG_bytes(drbg
, out
, count
);
951 /* Implements the default OpenSSL RAND_add() method */
952 static int drbg_add(const void *buf
, int num
, double randomness
)
955 RAND_DRBG
*drbg
= RAND_DRBG_get0_master();
960 if (num
< 0 || randomness
< 0.0)
963 if (randomness
> (double)drbg
->max_entropylen
) {
965 * The purpose of this check is to bound |randomness| by a
966 * relatively small value in order to prevent an integer
967 * overflow when multiplying by 8 in the rand_drbg_restart()
973 rand_drbg_lock(drbg
);
974 ret
= rand_drbg_restart(drbg
, buf
,
975 (size_t)(unsigned int)num
,
976 (size_t)(8*randomness
));
977 rand_drbg_unlock(drbg
);
982 /* Implements the default OpenSSL RAND_seed() method */
983 static int drbg_seed(const void *buf
, int num
)
985 return drbg_add(buf
, num
, num
);
988 /* Implements the default OpenSSL RAND_status() method */
989 static int drbg_status(void)
992 RAND_DRBG
*drbg
= RAND_DRBG_get0_master();
997 rand_drbg_lock(drbg
);
998 ret
= drbg
->state
== DRBG_READY
? 1 : 0;
999 rand_drbg_unlock(drbg
);
1004 * Get the master DRBG.
1005 * Returns pointer to the DRBG on success, NULL on failure.
1008 RAND_DRBG
*RAND_DRBG_get0_master(void)
1010 if (!RUN_ONCE(&rand_drbg_init
, do_rand_drbg_init
))
1017 * Get the public DRBG.
1018 * Returns pointer to the DRBG on success, NULL on failure.
1020 RAND_DRBG
*RAND_DRBG_get0_public(void)
1024 if (!RUN_ONCE(&rand_drbg_init
, do_rand_drbg_init
))
1027 drbg
= CRYPTO_THREAD_get_local(&public_drbg
);
1029 if (!ossl_init_thread_start(OPENSSL_INIT_THREAD_RAND
))
1031 drbg
= drbg_setup(master_drbg
);
1032 CRYPTO_THREAD_set_local(&public_drbg
, drbg
);
1038 * Get the private DRBG.
1039 * Returns pointer to the DRBG on success, NULL on failure.
1041 RAND_DRBG
*RAND_DRBG_get0_private(void)
1045 if (!RUN_ONCE(&rand_drbg_init
, do_rand_drbg_init
))
1048 drbg
= CRYPTO_THREAD_get_local(&private_drbg
);
1050 if (!ossl_init_thread_start(OPENSSL_INIT_THREAD_RAND
))
1052 drbg
= drbg_setup(master_drbg
);
1053 CRYPTO_THREAD_set_local(&private_drbg
, drbg
);
1058 RAND_METHOD rand_meth
= {
1067 RAND_METHOD
*RAND_OpenSSL(void)