xref: /freebsd/crypto/openssl/crypto/rand/rand_lib.c (revision e7be843b4a162e68651d3911f0357ed464915629)
1 /*
2  * Copyright 1995-2025 The OpenSSL Project Authors. All Rights Reserved.
3  *
4  * Licensed under the Apache License 2.0 (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
8  */
9 
10 /* We need to use some engine deprecated APIs */
11 #define OPENSSL_SUPPRESS_DEPRECATED
12 
13 #include <openssl/err.h>
14 #include <openssl/opensslconf.h>
15 #include <openssl/core_names.h>
16 #include <openssl/provider.h>
17 #include "internal/cryptlib.h"
18 #include "internal/provider.h"
19 #include "internal/thread_once.h"
20 #include "crypto/rand.h"
21 #include "crypto/cryptlib.h"
22 #include "rand_local.h"
23 #include "crypto/context.h"
24 #include "internal/provider.h"
25 
26 #ifndef OPENSSL_DEFAULT_SEED_SRC
27 # define OPENSSL_DEFAULT_SEED_SRC SEED-SRC
28 #endif
29 
30 typedef struct rand_global_st {
31     /*
32      * The three shared DRBG instances
33      *
34      * There are three shared DRBG instances: <primary>, <public>, and
35      * <private>.  The <public> and <private> DRBGs are secondary ones.
36      * These are used for non-secret (e.g. nonces) and secret
37      * (e.g. private keys) data respectively.
38      */
39     CRYPTO_RWLOCK *lock;
40 
41     EVP_RAND_CTX *seed;
42 
43     /*
44      * The <primary> DRBG
45      *
46      * Not used directly by the application, only for reseeding the two other
47      * DRBGs. It reseeds itself by pulling either randomness from os entropy
48      * sources or by consuming randomness which was added by RAND_add().
49      *
50      * The <primary> DRBG is a global instance which is accessed concurrently by
51      * all threads. The necessary locking is managed automatically by its child
52      * DRBG instances during reseeding.
53      */
54     EVP_RAND_CTX *primary;
55 
56     /*
57      * The provider which we'll use to generate randomness.
58      */
59 #ifndef FIPS_MODULE
60     OSSL_PROVIDER *random_provider;
61     char *random_provider_name;
62 #endif      /* !FIPS_MODULE */
63 
64     /*
65      * The <public> DRBG
66      *
67      * Used by default for generating random bytes using RAND_bytes().
68      *
69      * The <public> secondary DRBG is thread-local, i.e., there is one instance
70      * per thread.
71      */
72     CRYPTO_THREAD_LOCAL public;
73 
74     /*
75      * The <private> DRBG
76      *
77      * Used by default for generating private keys using RAND_priv_bytes()
78      *
79      * The <private> secondary DRBG is thread-local, i.e., there is one
80      * instance per thread.
81      */
82     CRYPTO_THREAD_LOCAL private;
83 
84     /* Which RNG is being used by default and it's configuration settings */
85     char *rng_name;
86     char *rng_cipher;
87     char *rng_digest;
88     char *rng_propq;
89 
90     /* Allow the randomness source to be changed */
91     char *seed_name;
92     char *seed_propq;
93 } RAND_GLOBAL;
94 
95 static EVP_RAND_CTX *rand_get0_primary(OSSL_LIB_CTX *ctx, RAND_GLOBAL *dgbl);
96 static EVP_RAND_CTX *rand_get0_public(OSSL_LIB_CTX *ctx, RAND_GLOBAL *dgbl);
97 static EVP_RAND_CTX *rand_get0_private(OSSL_LIB_CTX *ctx, RAND_GLOBAL *dgbl);
98 
rand_get_global(OSSL_LIB_CTX * libctx)99 static RAND_GLOBAL *rand_get_global(OSSL_LIB_CTX *libctx)
100 {
101     return ossl_lib_ctx_get_data(libctx, OSSL_LIB_CTX_DRBG_INDEX);
102 }
103 
104 #ifndef FIPS_MODULE
105 # include <stdio.h>
106 # include <time.h>
107 # include <limits.h>
108 # include <openssl/conf.h>
109 # include <openssl/trace.h>
110 # include <openssl/engine.h>
111 # include "crypto/rand_pool.h"
112 # include "prov/seeding.h"
113 # include "internal/e_os.h"
114 # include "internal/property.h"
115 
116 /*
117  * The default name for the random provider.
118  * This ensures that the FIPS provider will supply libcrypto's random byte
119  * requirements.
120  */
121 static const char random_provider_fips_name[] = "fips";
122 
set_random_provider_name(RAND_GLOBAL * dgbl,const char * name)123 static int set_random_provider_name(RAND_GLOBAL *dgbl, const char *name)
124 {
125     if (dgbl->random_provider_name != NULL
126             && OPENSSL_strcasecmp(dgbl->random_provider_name, name) == 0)
127         return 1;
128 
129     OPENSSL_free(dgbl->random_provider_name);
130     dgbl->random_provider_name = OPENSSL_strdup(name);
131     return dgbl->random_provider_name != NULL;
132 }
133 
134 # ifndef OPENSSL_NO_ENGINE
135 /* non-NULL if default_RAND_meth is ENGINE-provided */
136 static ENGINE *funct_ref;
137 static CRYPTO_RWLOCK *rand_engine_lock;
138 # endif     /* !OPENSSL_NO_ENGINE */
139 # ifndef OPENSSL_NO_DEPRECATED_3_0
140 static CRYPTO_RWLOCK *rand_meth_lock;
141 static const RAND_METHOD *default_RAND_meth;
142 # endif     /* !OPENSSL_NO_DEPRECATED_3_0 */
143 static CRYPTO_ONCE rand_init = CRYPTO_ONCE_STATIC_INIT;
144 
145 static int rand_inited = 0;
146 
DEFINE_RUN_ONCE_STATIC(do_rand_init)147 DEFINE_RUN_ONCE_STATIC(do_rand_init)
148 {
149 # ifndef OPENSSL_NO_ENGINE
150     rand_engine_lock = CRYPTO_THREAD_lock_new();
151     if (rand_engine_lock == NULL)
152         return 0;
153 # endif     /* !OPENSSL_NO_ENGINE */
154 
155 # ifndef OPENSSL_NO_DEPRECATED_3_0
156     rand_meth_lock = CRYPTO_THREAD_lock_new();
157     if (rand_meth_lock == NULL)
158         goto err;
159 # endif     /* !OPENSSL_NO_DEPRECATED_3_0 */
160 
161     if (!ossl_rand_pool_init())
162         goto err;
163 
164     rand_inited = 1;
165     return 1;
166 
167  err:
168 # ifndef OPENSSL_NO_DEPRECATED_3_0
169     CRYPTO_THREAD_lock_free(rand_meth_lock);
170     rand_meth_lock = NULL;
171 # endif     /* !OPENSSL_NO_DEPRECATED_3_0 */
172 # ifndef OPENSSL_NO_ENGINE
173     CRYPTO_THREAD_lock_free(rand_engine_lock);
174     rand_engine_lock = NULL;
175 # endif     /* !OPENSSL_NO_ENGINE */
176     return 0;
177 }
178 
ossl_rand_cleanup_int(void)179 void ossl_rand_cleanup_int(void)
180 {
181 # ifndef OPENSSL_NO_DEPRECATED_3_0
182     const RAND_METHOD *meth = default_RAND_meth;
183 
184     if (!rand_inited)
185         return;
186 
187     if (meth != NULL && meth->cleanup != NULL)
188         meth->cleanup();
189     RAND_set_rand_method(NULL);
190 # endif     /* !OPENSSL_NO_DEPRECATED_3_0 */
191     ossl_rand_pool_cleanup();
192 # ifndef OPENSSL_NO_ENGINE
193     CRYPTO_THREAD_lock_free(rand_engine_lock);
194     rand_engine_lock = NULL;
195 # endif     /* !OPENSSL_NO_ENGINE */
196 # ifndef OPENSSL_NO_DEPRECATED_3_0
197     CRYPTO_THREAD_lock_free(rand_meth_lock);
198     rand_meth_lock = NULL;
199 # endif     /* !OPENSSL_NO_DEPRECATED_3_0 */
200     ossl_release_default_drbg_ctx();
201     rand_inited = 0;
202 }
203 
204 /*
205  * RAND_close_seed_files() ensures that any seed file descriptors are
206  * closed after use.  This only applies to libcrypto/default provider,
207  * it does not apply to other providers.
208  */
RAND_keep_random_devices_open(int keep)209 void RAND_keep_random_devices_open(int keep)
210 {
211     if (RUN_ONCE(&rand_init, do_rand_init))
212         ossl_rand_pool_keep_random_devices_open(keep);
213 }
214 
215 /*
216  * RAND_poll() reseeds the default RNG using random input
217  *
218  * The random input is obtained from polling various entropy
219  * sources which depend on the operating system and are
220  * configurable via the --with-rand-seed configure option.
221  */
RAND_poll(void)222 int RAND_poll(void)
223 {
224     static const char salt[] = "polling";
225 
226 # ifndef OPENSSL_NO_DEPRECATED_3_0
227     const RAND_METHOD *meth = RAND_get_rand_method();
228     int ret = meth == RAND_OpenSSL();
229 
230     if (meth == NULL)
231         return 0;
232 
233     if (!ret) {
234         /* fill random pool and seed the current legacy RNG */
235         RAND_POOL *pool = ossl_rand_pool_new(RAND_DRBG_STRENGTH, 1,
236                                              (RAND_DRBG_STRENGTH + 7) / 8,
237                                              RAND_POOL_MAX_LENGTH);
238 
239         if (pool == NULL)
240             return 0;
241 
242         if (ossl_pool_acquire_entropy(pool) == 0)
243             goto err;
244 
245         if (meth->add == NULL
246             || meth->add(ossl_rand_pool_buffer(pool),
247                          ossl_rand_pool_length(pool),
248                          (ossl_rand_pool_entropy(pool) / 8.0)) == 0)
249             goto err;
250 
251         ret = 1;
252      err:
253         ossl_rand_pool_free(pool);
254         return ret;
255     }
256 # endif     /* !OPENSSL_NO_DEPRECATED_3_0 */
257 
258     RAND_seed(salt, sizeof(salt));
259     return 1;
260 }
261 
262 # ifndef OPENSSL_NO_DEPRECATED_3_0
rand_set_rand_method_internal(const RAND_METHOD * meth,ossl_unused ENGINE * e)263 static int rand_set_rand_method_internal(const RAND_METHOD *meth,
264                                          ossl_unused ENGINE *e)
265 {
266     if (!RUN_ONCE(&rand_init, do_rand_init))
267         return 0;
268 
269     if (!CRYPTO_THREAD_write_lock(rand_meth_lock))
270         return 0;
271 #  ifndef OPENSSL_NO_ENGINE
272     ENGINE_finish(funct_ref);
273     funct_ref = e;
274 #  endif
275     default_RAND_meth = meth;
276     CRYPTO_THREAD_unlock(rand_meth_lock);
277     return 1;
278 }
279 
RAND_set_rand_method(const RAND_METHOD * meth)280 int RAND_set_rand_method(const RAND_METHOD *meth)
281 {
282     return rand_set_rand_method_internal(meth, NULL);
283 }
284 
RAND_get_rand_method(void)285 const RAND_METHOD *RAND_get_rand_method(void)
286 {
287     const RAND_METHOD *tmp_meth = NULL;
288 
289     if (!RUN_ONCE(&rand_init, do_rand_init))
290         return NULL;
291 
292     if (rand_meth_lock == NULL)
293         return NULL;
294 
295     if (!CRYPTO_THREAD_read_lock(rand_meth_lock))
296         return NULL;
297     tmp_meth = default_RAND_meth;
298     CRYPTO_THREAD_unlock(rand_meth_lock);
299     if (tmp_meth != NULL)
300         return tmp_meth;
301 
302     if (!CRYPTO_THREAD_write_lock(rand_meth_lock))
303         return NULL;
304     if (default_RAND_meth == NULL) {
305 #  ifndef OPENSSL_NO_ENGINE
306         ENGINE *e;
307 
308         /* If we have an engine that can do RAND, use it. */
309         if ((e = ENGINE_get_default_RAND()) != NULL
310                 && (tmp_meth = ENGINE_get_RAND(e)) != NULL) {
311             funct_ref = e;
312             default_RAND_meth = tmp_meth;
313         } else {
314             ENGINE_finish(e);
315             default_RAND_meth = &ossl_rand_meth;
316         }
317 #  else
318         default_RAND_meth = &ossl_rand_meth;
319 #  endif
320     }
321     tmp_meth = default_RAND_meth;
322     CRYPTO_THREAD_unlock(rand_meth_lock);
323     return tmp_meth;
324 }
325 
326 #  if !defined(OPENSSL_NO_ENGINE)
RAND_set_rand_engine(ENGINE * engine)327 int RAND_set_rand_engine(ENGINE *engine)
328 {
329     const RAND_METHOD *tmp_meth = NULL;
330 
331     if (!RUN_ONCE(&rand_init, do_rand_init))
332         return 0;
333 
334     if (engine != NULL) {
335         if (!ENGINE_init(engine))
336             return 0;
337         tmp_meth = ENGINE_get_RAND(engine);
338         if (tmp_meth == NULL) {
339             ENGINE_finish(engine);
340             return 0;
341         }
342     }
343     if (!CRYPTO_THREAD_write_lock(rand_engine_lock)) {
344         ENGINE_finish(engine);
345         return 0;
346     }
347 
348     /* This function releases any prior ENGINE so call it first */
349     rand_set_rand_method_internal(tmp_meth, engine);
350     CRYPTO_THREAD_unlock(rand_engine_lock);
351     return 1;
352 }
353 #  endif
354 # endif /* OPENSSL_NO_DEPRECATED_3_0 */
355 
RAND_seed(const void * buf,int num)356 void RAND_seed(const void *buf, int num)
357 {
358     EVP_RAND_CTX *drbg;
359 # ifndef OPENSSL_NO_DEPRECATED_3_0
360     const RAND_METHOD *meth = RAND_get_rand_method();
361 
362     if (meth != NULL && meth->seed != NULL) {
363         meth->seed(buf, num);
364         return;
365     }
366 # endif
367 
368     drbg = RAND_get0_primary(NULL);
369     if (drbg != NULL && num > 0)
370         EVP_RAND_reseed(drbg, 0, NULL, 0, buf, num);
371 }
372 
RAND_add(const void * buf,int num,double randomness)373 void RAND_add(const void *buf, int num, double randomness)
374 {
375     EVP_RAND_CTX *drbg;
376 # ifndef OPENSSL_NO_DEPRECATED_3_0
377     const RAND_METHOD *meth = RAND_get_rand_method();
378 
379     if (meth != NULL && meth->add != NULL) {
380         meth->add(buf, num, randomness);
381         return;
382     }
383 # endif
384     drbg = RAND_get0_primary(NULL);
385     if (drbg != NULL && num > 0)
386 # ifdef OPENSSL_RAND_SEED_NONE
387         /* Without an entropy source, we have to rely on the user */
388         EVP_RAND_reseed(drbg, 0, buf, num, NULL, 0);
389 # else
390         /* With an entropy source, we downgrade this to additional input */
391         EVP_RAND_reseed(drbg, 0, NULL, 0, buf, num);
392 # endif
393 }
394 
395 # if !defined(OPENSSL_NO_DEPRECATED_1_1_0)
RAND_pseudo_bytes(unsigned char * buf,int num)396 int RAND_pseudo_bytes(unsigned char *buf, int num)
397 {
398     const RAND_METHOD *meth = RAND_get_rand_method();
399 
400     if (meth != NULL && meth->pseudorand != NULL)
401         return meth->pseudorand(buf, num);
402     ERR_raise(ERR_LIB_RAND, RAND_R_FUNC_NOT_IMPLEMENTED);
403     return -1;
404 }
405 # endif
406 
RAND_status(void)407 int RAND_status(void)
408 {
409     EVP_RAND_CTX *rand;
410 # ifndef OPENSSL_NO_DEPRECATED_3_0
411     const RAND_METHOD *meth = RAND_get_rand_method();
412 
413     if (meth != NULL && meth != RAND_OpenSSL())
414         return meth->status != NULL ? meth->status() : 0;
415 # endif
416 
417     if ((rand = RAND_get0_primary(NULL)) == NULL)
418         return 0;
419     return EVP_RAND_get_state(rand) == EVP_RAND_STATE_READY;
420 }
421 # else  /* !FIPS_MODULE */
422 
423 # ifndef OPENSSL_NO_DEPRECATED_3_0
RAND_get_rand_method(void)424 const RAND_METHOD *RAND_get_rand_method(void)
425 {
426     return NULL;
427 }
428 # endif
429 #endif /* !FIPS_MODULE */
430 
431 /*
432  * This function is not part of RAND_METHOD, so if we're not using
433  * the default method, then just call RAND_bytes().  Otherwise make
434  * sure we're instantiated and use the private DRBG.
435  */
RAND_priv_bytes_ex(OSSL_LIB_CTX * ctx,unsigned char * buf,size_t num,unsigned int strength)436 int RAND_priv_bytes_ex(OSSL_LIB_CTX *ctx, unsigned char *buf, size_t num,
437                        unsigned int strength)
438 {
439     RAND_GLOBAL *dgbl;
440     EVP_RAND_CTX *rand;
441 #if !defined(OPENSSL_NO_DEPRECATED_3_0) && !defined(FIPS_MODULE)
442     const RAND_METHOD *meth = RAND_get_rand_method();
443 
444     if (meth != NULL && meth != RAND_OpenSSL()) {
445         if (meth->bytes != NULL)
446             return meth->bytes(buf, num);
447         ERR_raise(ERR_LIB_RAND, RAND_R_FUNC_NOT_IMPLEMENTED);
448         return -1;
449     }
450 #endif
451 
452     dgbl = rand_get_global(ctx);
453     if (dgbl == NULL)
454         return 0;
455 #ifndef FIPS_MODULE
456     if (dgbl->random_provider != NULL)
457         return ossl_provider_random_bytes(dgbl->random_provider,
458                                           OSSL_PROV_RANDOM_PRIVATE,
459                                           buf, num, strength);
460 #endif      /* !FIPS_MODULE */
461     rand = rand_get0_private(ctx, dgbl);
462     if (rand != NULL)
463         return EVP_RAND_generate(rand, buf, num, strength, 0, NULL, 0);
464 
465     return 0;
466 }
467 
RAND_priv_bytes(unsigned char * buf,int num)468 int RAND_priv_bytes(unsigned char *buf, int num)
469 {
470     if (num < 0)
471         return 0;
472     return RAND_priv_bytes_ex(NULL, buf, (size_t)num, 0);
473 }
474 
RAND_bytes_ex(OSSL_LIB_CTX * ctx,unsigned char * buf,size_t num,unsigned int strength)475 int RAND_bytes_ex(OSSL_LIB_CTX *ctx, unsigned char *buf, size_t num,
476                   unsigned int strength)
477 {
478     RAND_GLOBAL *dgbl;
479     EVP_RAND_CTX *rand;
480 #if !defined(OPENSSL_NO_DEPRECATED_3_0) && !defined(FIPS_MODULE)
481     const RAND_METHOD *meth = RAND_get_rand_method();
482 
483     if (meth != NULL && meth != RAND_OpenSSL()) {
484         if (meth->bytes != NULL)
485             return meth->bytes(buf, num);
486         ERR_raise(ERR_LIB_RAND, RAND_R_FUNC_NOT_IMPLEMENTED);
487         return -1;
488     }
489 #endif
490 
491     dgbl = rand_get_global(ctx);
492     if (dgbl == NULL)
493         return 0;
494 #ifndef FIPS_MODULE
495     if (dgbl->random_provider != NULL)
496         return ossl_provider_random_bytes(dgbl->random_provider,
497                                           OSSL_PROV_RANDOM_PUBLIC,
498                                           buf, num, strength);
499 #endif      /* !FIPS_MODULE */
500 
501     rand = rand_get0_public(ctx, dgbl);
502     if (rand != NULL)
503         return EVP_RAND_generate(rand, buf, num, strength, 0, NULL, 0);
504 
505     return 0;
506 }
507 
RAND_bytes(unsigned char * buf,int num)508 int RAND_bytes(unsigned char *buf, int num)
509 {
510     if (num < 0)
511         return 0;
512     return RAND_bytes_ex(NULL, buf, (size_t)num, 0);
513 }
514 
515 /*
516  * Initialize the OSSL_LIB_CTX global DRBGs on first use.
517  * Returns the allocated global data on success or NULL on failure.
518  */
ossl_rand_ctx_new(OSSL_LIB_CTX * libctx)519 void *ossl_rand_ctx_new(OSSL_LIB_CTX *libctx)
520 {
521     RAND_GLOBAL *dgbl = OPENSSL_zalloc(sizeof(*dgbl));
522 
523     if (dgbl == NULL)
524         return NULL;
525 
526 #ifndef FIPS_MODULE
527     /*
528      * We need to ensure that base libcrypto thread handling has been
529      * initialised.
530      */
531     OPENSSL_init_crypto(OPENSSL_INIT_BASE_ONLY, NULL);
532 
533     /* Prepopulate the random provider name */
534     dgbl->random_provider_name = OPENSSL_strdup(random_provider_fips_name);
535     if (dgbl->random_provider_name == NULL)
536         goto err0;
537 #endif
538 
539     dgbl->lock = CRYPTO_THREAD_lock_new();
540     if (dgbl->lock == NULL)
541         goto err1;
542 
543     if (!CRYPTO_THREAD_init_local(&dgbl->private, NULL))
544         goto err1;
545 
546     if (!CRYPTO_THREAD_init_local(&dgbl->public, NULL))
547         goto err2;
548 
549     return dgbl;
550 
551  err2:
552     CRYPTO_THREAD_cleanup_local(&dgbl->private);
553  err1:
554     CRYPTO_THREAD_lock_free(dgbl->lock);
555 #ifndef FIPS_MODULE
556  err0:
557     OPENSSL_free(dgbl->random_provider_name);
558 #endif
559     OPENSSL_free(dgbl);
560     return NULL;
561 }
562 
ossl_rand_ctx_free(void * vdgbl)563 void ossl_rand_ctx_free(void *vdgbl)
564 {
565     RAND_GLOBAL *dgbl = vdgbl;
566 
567     if (dgbl == NULL)
568         return;
569 
570     CRYPTO_THREAD_lock_free(dgbl->lock);
571     CRYPTO_THREAD_cleanup_local(&dgbl->private);
572     CRYPTO_THREAD_cleanup_local(&dgbl->public);
573     EVP_RAND_CTX_free(dgbl->primary);
574     EVP_RAND_CTX_free(dgbl->seed);
575 #ifndef FIPS_MODULE
576     OPENSSL_free(dgbl->random_provider_name);
577 #endif      /* !FIPS_MODULE */
578     OPENSSL_free(dgbl->rng_name);
579     OPENSSL_free(dgbl->rng_cipher);
580     OPENSSL_free(dgbl->rng_digest);
581     OPENSSL_free(dgbl->rng_propq);
582     OPENSSL_free(dgbl->seed_name);
583     OPENSSL_free(dgbl->seed_propq);
584 
585     OPENSSL_free(dgbl);
586 }
587 
rand_delete_thread_state(void * arg)588 static void rand_delete_thread_state(void *arg)
589 {
590     OSSL_LIB_CTX *ctx = arg;
591     RAND_GLOBAL *dgbl = rand_get_global(ctx);
592     EVP_RAND_CTX *rand;
593 
594     if (dgbl == NULL)
595         return;
596 
597     rand = CRYPTO_THREAD_get_local(&dgbl->public);
598     CRYPTO_THREAD_set_local(&dgbl->public, NULL);
599     EVP_RAND_CTX_free(rand);
600 
601     rand = CRYPTO_THREAD_get_local(&dgbl->private);
602     CRYPTO_THREAD_set_local(&dgbl->private, NULL);
603     EVP_RAND_CTX_free(rand);
604 }
605 
606 #if !defined(FIPS_MODULE) || !defined(OPENSSL_NO_FIPS_JITTER)
rand_new_seed(OSSL_LIB_CTX * libctx)607 static EVP_RAND_CTX *rand_new_seed(OSSL_LIB_CTX *libctx)
608 {
609     EVP_RAND *rand;
610     const char *propq;
611     char *name;
612     EVP_RAND_CTX *ctx = NULL;
613 # ifdef OPENSSL_NO_FIPS_JITTER
614     RAND_GLOBAL *dgbl = rand_get_global(libctx);
615 
616     if (dgbl == NULL)
617         return NULL;
618     propq = dgbl->seed_propq;
619     name = dgbl->seed_name != NULL ? dgbl->seed_name
620                                    : OPENSSL_MSTR(OPENSSL_DEFAULT_SEED_SRC);
621 # else /* !OPENSSL_NO_FIPS_JITTER */
622     name = "JITTER";
623     propq = "";
624 # endif /* OPENSSL_NO_FIPS_JITTER */
625 
626     rand = EVP_RAND_fetch(libctx, name, propq);
627     if (rand == NULL) {
628         ERR_raise(ERR_LIB_RAND, RAND_R_UNABLE_TO_FETCH_DRBG);
629         goto err;
630     }
631     ctx = EVP_RAND_CTX_new(rand, NULL);
632     EVP_RAND_free(rand);
633     if (ctx == NULL) {
634         ERR_raise(ERR_LIB_RAND, RAND_R_UNABLE_TO_CREATE_DRBG);
635         goto err;
636     }
637     if (!EVP_RAND_instantiate(ctx, 0, 0, NULL, 0, NULL)) {
638         ERR_raise(ERR_LIB_RAND, RAND_R_ERROR_INSTANTIATING_DRBG);
639         goto err;
640     }
641     return ctx;
642  err:
643     EVP_RAND_CTX_free(ctx);
644     return NULL;
645 }
646 #endif  /* !FIPS_MODULE || !OPENSSL_NO_FIPS_JITTER */
647 
648 #ifndef FIPS_MODULE
ossl_rand_get0_seed_noncreating(OSSL_LIB_CTX * ctx)649 EVP_RAND_CTX *ossl_rand_get0_seed_noncreating(OSSL_LIB_CTX *ctx)
650 {
651     RAND_GLOBAL *dgbl = rand_get_global(ctx);
652     EVP_RAND_CTX *ret;
653 
654     if (dgbl == NULL)
655         return NULL;
656 
657     if (!CRYPTO_THREAD_read_lock(dgbl->lock))
658         return NULL;
659     ret = dgbl->seed;
660     CRYPTO_THREAD_unlock(dgbl->lock);
661     return ret;
662 }
663 #endif  /* !FIPS_MODULE */
664 
rand_new_drbg(OSSL_LIB_CTX * libctx,EVP_RAND_CTX * parent,unsigned int reseed_interval,time_t reseed_time_interval)665 static EVP_RAND_CTX *rand_new_drbg(OSSL_LIB_CTX *libctx, EVP_RAND_CTX *parent,
666                                    unsigned int reseed_interval,
667                                    time_t reseed_time_interval)
668 {
669     EVP_RAND *rand;
670     RAND_GLOBAL *dgbl = rand_get_global(libctx);
671     EVP_RAND_CTX *ctx;
672     OSSL_PARAM params[9], *p = params;
673     const OSSL_PARAM *settables;
674     const char *prov_name;
675     char *name, *cipher;
676     int use_df = 1;
677 
678     if (dgbl == NULL)
679         return NULL;
680     name = dgbl->rng_name != NULL ? dgbl->rng_name : "CTR-DRBG";
681     rand = EVP_RAND_fetch(libctx, name, dgbl->rng_propq);
682     if (rand == NULL) {
683         ERR_raise(ERR_LIB_RAND, RAND_R_UNABLE_TO_FETCH_DRBG);
684         return NULL;
685     }
686     prov_name = ossl_provider_name(EVP_RAND_get0_provider(rand));
687     ctx = EVP_RAND_CTX_new(rand, parent);
688     EVP_RAND_free(rand);
689     if (ctx == NULL) {
690         ERR_raise(ERR_LIB_RAND, RAND_R_UNABLE_TO_CREATE_DRBG);
691         return NULL;
692     }
693 
694     settables = EVP_RAND_CTX_settable_params(ctx);
695     if (OSSL_PARAM_locate_const(settables, OSSL_DRBG_PARAM_CIPHER)) {
696         cipher = dgbl->rng_cipher != NULL ? dgbl->rng_cipher : "AES-256-CTR";
697         *p++ = OSSL_PARAM_construct_utf8_string(OSSL_DRBG_PARAM_CIPHER,
698                                                 cipher, 0);
699     }
700     if (dgbl->rng_digest != NULL
701             && OSSL_PARAM_locate_const(settables, OSSL_DRBG_PARAM_DIGEST))
702         *p++ = OSSL_PARAM_construct_utf8_string(OSSL_DRBG_PARAM_DIGEST,
703                                                 dgbl->rng_digest, 0);
704     if (prov_name != NULL)
705         *p++ = OSSL_PARAM_construct_utf8_string(OSSL_PROV_PARAM_CORE_PROV_NAME,
706                                                 (char *)prov_name, 0);
707     if (dgbl->rng_propq != NULL)
708         *p++ = OSSL_PARAM_construct_utf8_string(OSSL_DRBG_PARAM_PROPERTIES,
709                                                 dgbl->rng_propq, 0);
710     if (OSSL_PARAM_locate_const(settables, OSSL_ALG_PARAM_MAC))
711         *p++ = OSSL_PARAM_construct_utf8_string(OSSL_ALG_PARAM_MAC, "HMAC", 0);
712     if (OSSL_PARAM_locate_const(settables, OSSL_DRBG_PARAM_USE_DF))
713         *p++ = OSSL_PARAM_construct_int(OSSL_DRBG_PARAM_USE_DF, &use_df);
714     *p++ = OSSL_PARAM_construct_uint(OSSL_DRBG_PARAM_RESEED_REQUESTS,
715                                      &reseed_interval);
716     *p++ = OSSL_PARAM_construct_time_t(OSSL_DRBG_PARAM_RESEED_TIME_INTERVAL,
717                                        &reseed_time_interval);
718     *p = OSSL_PARAM_construct_end();
719     if (!EVP_RAND_instantiate(ctx, 0, 0, NULL, 0, params)) {
720         ERR_raise(ERR_LIB_RAND, RAND_R_ERROR_INSTANTIATING_DRBG);
721         EVP_RAND_CTX_free(ctx);
722         return NULL;
723     }
724     return ctx;
725 }
726 
727 #if defined(FIPS_MODULE)
rand_new_crngt(OSSL_LIB_CTX * libctx,EVP_RAND_CTX * parent)728 static EVP_RAND_CTX *rand_new_crngt(OSSL_LIB_CTX *libctx, EVP_RAND_CTX *parent)
729 {
730     EVP_RAND *rand;
731     EVP_RAND_CTX *ctx;
732 
733     rand = EVP_RAND_fetch(libctx, "CRNG-TEST", "-fips");
734     if (rand == NULL) {
735         ERR_raise(ERR_LIB_RAND, RAND_R_UNABLE_TO_FETCH_DRBG);
736         return NULL;
737     }
738     ctx = EVP_RAND_CTX_new(rand, parent);
739     EVP_RAND_free(rand);
740     if (ctx == NULL) {
741         ERR_raise(ERR_LIB_RAND, RAND_R_UNABLE_TO_CREATE_DRBG);
742         return NULL;
743     }
744 
745     if (!EVP_RAND_instantiate(ctx, 0, 0, NULL, 0, NULL)) {
746         ERR_raise(ERR_LIB_RAND, RAND_R_ERROR_INSTANTIATING_DRBG);
747         EVP_RAND_CTX_free(ctx);
748         return NULL;
749     }
750     return ctx;
751 }
752 #endif  /* FIPS_MODULE */
753 
754 /*
755  * Get the primary random generator.
756  * Returns pointer to its EVP_RAND_CTX on success, NULL on failure.
757  *
758  */
rand_get0_primary(OSSL_LIB_CTX * ctx,RAND_GLOBAL * dgbl)759 static EVP_RAND_CTX *rand_get0_primary(OSSL_LIB_CTX *ctx, RAND_GLOBAL *dgbl)
760 {
761     EVP_RAND_CTX *ret, *seed, *newseed = NULL, *primary;
762 
763     if (dgbl == NULL)
764         return NULL;
765 
766     if (!CRYPTO_THREAD_read_lock(dgbl->lock))
767         return NULL;
768 
769     ret = dgbl->primary;
770     seed = dgbl->seed;
771     CRYPTO_THREAD_unlock(dgbl->lock);
772 
773     if (ret != NULL)
774         return ret;
775 
776 #if !defined(FIPS_MODULE) || !defined(OPENSSL_NO_FIPS_JITTER)
777     /* Create a seed source for libcrypto or jitter enabled FIPS provider */
778     if (seed == NULL) {
779         ERR_set_mark();
780         seed = newseed = rand_new_seed(ctx);
781         ERR_pop_to_mark();
782     }
783 #endif  /* !FIPS_MODULE || !OPENSSL_NO_FIPS_JITTER */
784 
785 #if defined(FIPS_MODULE)
786     /* The FIPS provider has entropy health tests instead of the primary */
787     ret = rand_new_crngt(ctx, seed);
788 #else   /* FIPS_MODULE */
789     ret = rand_new_drbg(ctx, seed, PRIMARY_RESEED_INTERVAL,
790                         PRIMARY_RESEED_TIME_INTERVAL);
791 #endif  /* FIPS_MODULE */
792 
793     /*
794      * The primary DRBG may be shared between multiple threads so we must
795      * enable locking.
796      */
797     if (ret == NULL || !EVP_RAND_enable_locking(ret)) {
798         if (ret != NULL) {
799             ERR_raise(ERR_LIB_EVP, EVP_R_UNABLE_TO_ENABLE_LOCKING);
800             EVP_RAND_CTX_free(ret);
801         }
802         if (newseed == NULL)
803             return NULL;
804         /* else carry on and store seed */
805         ret = NULL;
806     }
807 
808     if (!CRYPTO_THREAD_write_lock(dgbl->lock))
809         return NULL;
810 
811     primary = dgbl->primary;
812     if (primary != NULL) {
813         CRYPTO_THREAD_unlock(dgbl->lock);
814         EVP_RAND_CTX_free(ret);
815         EVP_RAND_CTX_free(newseed);
816         return primary;
817     }
818     if (newseed != NULL)
819         dgbl->seed = newseed;
820     dgbl->primary = ret;
821     CRYPTO_THREAD_unlock(dgbl->lock);
822 
823     return ret;
824 }
825 
826 /*
827  * Get the primary random generator.
828  * Returns pointer to its EVP_RAND_CTX on success, NULL on failure.
829  *
830  */
RAND_get0_primary(OSSL_LIB_CTX * ctx)831 EVP_RAND_CTX *RAND_get0_primary(OSSL_LIB_CTX *ctx)
832 {
833     RAND_GLOBAL *dgbl = rand_get_global(ctx);
834 
835     return dgbl == NULL ? NULL : rand_get0_primary(ctx, dgbl);
836 }
837 
rand_get0_public(OSSL_LIB_CTX * ctx,RAND_GLOBAL * dgbl)838 static EVP_RAND_CTX *rand_get0_public(OSSL_LIB_CTX *ctx, RAND_GLOBAL *dgbl)
839 {
840     EVP_RAND_CTX *rand, *primary;
841 
842     if (dgbl == NULL)
843         return NULL;
844 
845     rand = CRYPTO_THREAD_get_local(&dgbl->public);
846     if (rand == NULL) {
847         primary = rand_get0_primary(ctx, dgbl);
848         if (primary == NULL)
849             return NULL;
850 
851         ctx = ossl_lib_ctx_get_concrete(ctx);
852 
853         if (ctx == NULL)
854             return NULL;
855         /*
856          * If the private is also NULL then this is the first time we've
857          * used this thread.
858          */
859         if (CRYPTO_THREAD_get_local(&dgbl->private) == NULL
860                 && !ossl_init_thread_start(NULL, ctx, rand_delete_thread_state))
861             return NULL;
862         rand = rand_new_drbg(ctx, primary, SECONDARY_RESEED_INTERVAL,
863                              SECONDARY_RESEED_TIME_INTERVAL);
864         CRYPTO_THREAD_set_local(&dgbl->public, rand);
865     }
866     return rand;
867 }
868 
869 /*
870  * Get the public random generator.
871  * Returns pointer to its EVP_RAND_CTX on success, NULL on failure.
872  */
RAND_get0_public(OSSL_LIB_CTX * ctx)873 EVP_RAND_CTX *RAND_get0_public(OSSL_LIB_CTX *ctx)
874 {
875     RAND_GLOBAL *dgbl = rand_get_global(ctx);
876 
877     return dgbl == NULL ? NULL : rand_get0_public(ctx, dgbl);
878 }
879 
rand_get0_private(OSSL_LIB_CTX * ctx,RAND_GLOBAL * dgbl)880 static EVP_RAND_CTX *rand_get0_private(OSSL_LIB_CTX *ctx, RAND_GLOBAL *dgbl)
881 {
882     EVP_RAND_CTX *rand, *primary;
883 
884     rand = CRYPTO_THREAD_get_local(&dgbl->private);
885     if (rand == NULL) {
886         primary = rand_get0_primary(ctx, dgbl);
887         if (primary == NULL)
888             return NULL;
889 
890         ctx = ossl_lib_ctx_get_concrete(ctx);
891 
892         if (ctx == NULL)
893             return NULL;
894         /*
895          * If the public is also NULL then this is the first time we've
896          * used this thread.
897          */
898         if (CRYPTO_THREAD_get_local(&dgbl->public) == NULL
899                 && !ossl_init_thread_start(NULL, ctx, rand_delete_thread_state))
900             return NULL;
901         rand = rand_new_drbg(ctx, primary, SECONDARY_RESEED_INTERVAL,
902                              SECONDARY_RESEED_TIME_INTERVAL);
903         CRYPTO_THREAD_set_local(&dgbl->private, rand);
904     }
905     return rand;
906 }
907 
908 /*
909  * Get the private random generator.
910  * Returns pointer to its EVP_RAND_CTX on success, NULL on failure.
911  */
RAND_get0_private(OSSL_LIB_CTX * ctx)912 EVP_RAND_CTX *RAND_get0_private(OSSL_LIB_CTX *ctx)
913 {
914     RAND_GLOBAL *dgbl = rand_get_global(ctx);
915 
916     return dgbl == NULL ? NULL : rand_get0_private(ctx, dgbl);
917 }
918 
919 #ifdef FIPS_MODULE
ossl_rand_get0_private_noncreating(OSSL_LIB_CTX * ctx)920 EVP_RAND_CTX *ossl_rand_get0_private_noncreating(OSSL_LIB_CTX *ctx)
921 {
922     RAND_GLOBAL *dgbl = rand_get_global(ctx);
923 
924     if (dgbl == NULL)
925         return NULL;
926 
927     return CRYPTO_THREAD_get_local(&dgbl->private);
928 }
929 #endif
930 
RAND_set0_public(OSSL_LIB_CTX * ctx,EVP_RAND_CTX * rand)931 int RAND_set0_public(OSSL_LIB_CTX *ctx, EVP_RAND_CTX *rand)
932 {
933     RAND_GLOBAL *dgbl = rand_get_global(ctx);
934     EVP_RAND_CTX *old;
935     int r;
936 
937     if (dgbl == NULL)
938         return 0;
939     old = CRYPTO_THREAD_get_local(&dgbl->public);
940     if ((r = CRYPTO_THREAD_set_local(&dgbl->public, rand)) > 0)
941         EVP_RAND_CTX_free(old);
942     return r;
943 }
944 
RAND_set0_private(OSSL_LIB_CTX * ctx,EVP_RAND_CTX * rand)945 int RAND_set0_private(OSSL_LIB_CTX *ctx, EVP_RAND_CTX *rand)
946 {
947     RAND_GLOBAL *dgbl = rand_get_global(ctx);
948     EVP_RAND_CTX *old;
949     int r;
950 
951     if (dgbl == NULL)
952         return 0;
953     old = CRYPTO_THREAD_get_local(&dgbl->private);
954     if ((r = CRYPTO_THREAD_set_local(&dgbl->private, rand)) > 0)
955         EVP_RAND_CTX_free(old);
956     return r;
957 }
958 
959 #ifndef FIPS_MODULE
random_set_string(char ** p,const char * s)960 static int random_set_string(char **p, const char *s)
961 {
962     char *d = NULL;
963 
964     if (s != NULL) {
965         d = OPENSSL_strdup(s);
966         if (d == NULL)
967             return 0;
968     }
969     OPENSSL_free(*p);
970     *p = d;
971     return 1;
972 }
973 
974 /*
975  * Load the DRBG definitions from a configuration file.
976  */
random_conf_init(CONF_IMODULE * md,const CONF * cnf)977 static int random_conf_init(CONF_IMODULE *md, const CONF *cnf)
978 {
979     STACK_OF(CONF_VALUE) *elist;
980     CONF_VALUE *cval;
981     OSSL_LIB_CTX *libctx = NCONF_get0_libctx((CONF *)cnf);
982     RAND_GLOBAL *dgbl = rand_get_global(libctx);
983     int i, r = 1;
984 
985     OSSL_TRACE1(CONF, "Loading random module: section %s\n",
986                 CONF_imodule_get_value(md));
987 
988     /* Value is a section containing RANDOM configuration */
989     elist = NCONF_get_section(cnf, CONF_imodule_get_value(md));
990     if (elist == NULL) {
991         ERR_raise(ERR_LIB_CRYPTO, CRYPTO_R_RANDOM_SECTION_ERROR);
992         return 0;
993     }
994 
995     if (dgbl == NULL)
996         return 0;
997 
998     for (i = 0; i < sk_CONF_VALUE_num(elist); i++) {
999         cval = sk_CONF_VALUE_value(elist, i);
1000         if (OPENSSL_strcasecmp(cval->name, "random") == 0) {
1001             if (!random_set_string(&dgbl->rng_name, cval->value))
1002                 return 0;
1003         } else if (OPENSSL_strcasecmp(cval->name, "cipher") == 0) {
1004             if (!random_set_string(&dgbl->rng_cipher, cval->value))
1005                 return 0;
1006         } else if (OPENSSL_strcasecmp(cval->name, "digest") == 0) {
1007             if (!random_set_string(&dgbl->rng_digest, cval->value))
1008                 return 0;
1009         } else if (OPENSSL_strcasecmp(cval->name, "properties") == 0) {
1010             if (!random_set_string(&dgbl->rng_propq, cval->value))
1011                 return 0;
1012         } else if (OPENSSL_strcasecmp(cval->name, "seed") == 0) {
1013             if (!random_set_string(&dgbl->seed_name, cval->value))
1014                 return 0;
1015         } else if (OPENSSL_strcasecmp(cval->name, "seed_properties") == 0) {
1016             if (!random_set_string(&dgbl->seed_propq, cval->value))
1017                 return 0;
1018         } else if (OPENSSL_strcasecmp(cval->name, "random_provider") == 0) {
1019 # ifndef FIPS_MODULE
1020             OSSL_PROVIDER *prov = ossl_provider_find(libctx, cval->value, 0);
1021 
1022             if (prov != NULL) {
1023                 if (!RAND_set1_random_provider(libctx, prov)) {
1024                     ERR_raise(ERR_LIB_CRYPTO, ERR_R_INTERNAL_ERROR);
1025                     OSSL_PROVIDER_unload(prov);
1026                     return 0;
1027                 }
1028                 /*
1029                  * We need to release the reference from ossl_provider_find because
1030                  * we don't want to keep a reference counted handle to the provider.
1031                  *
1032                  * The provider unload code checks for the random provider and,
1033                  * if present, our reference will be NULLed when it is fully freed.
1034                  * The provider load code, conversely, checks the provider name
1035                  * and re-hooks our reference if required.  This means that a load,
1036                  * hook random provider, use, unload, reload, reuse sequence will
1037                  * work as expected.
1038                  */
1039                 OSSL_PROVIDER_unload(prov);
1040             } else if (!set_random_provider_name(dgbl, cval->value))
1041                 return 0;
1042 # endif
1043         } else {
1044             ERR_raise_data(ERR_LIB_CRYPTO,
1045                            CRYPTO_R_UNKNOWN_NAME_IN_RANDOM_SECTION,
1046                            "name=%s, value=%s", cval->name, cval->value);
1047             r = 0;
1048         }
1049     }
1050     return r;
1051 }
1052 
1053 
random_conf_deinit(CONF_IMODULE * md)1054 static void random_conf_deinit(CONF_IMODULE *md)
1055 {
1056     OSSL_TRACE(CONF, "Cleaned up random\n");
1057 }
1058 
ossl_random_add_conf_module(void)1059 void ossl_random_add_conf_module(void)
1060 {
1061     OSSL_TRACE(CONF, "Adding config module 'random'\n");
1062     CONF_module_add("random", random_conf_init, random_conf_deinit);
1063 }
1064 
RAND_set_DRBG_type(OSSL_LIB_CTX * ctx,const char * drbg,const char * propq,const char * cipher,const char * digest)1065 int RAND_set_DRBG_type(OSSL_LIB_CTX *ctx, const char *drbg, const char *propq,
1066                        const char *cipher, const char *digest)
1067 {
1068     RAND_GLOBAL *dgbl = rand_get_global(ctx);
1069 
1070     if (dgbl == NULL)
1071         return 0;
1072     if (dgbl->primary != NULL) {
1073         ERR_raise(ERR_LIB_CRYPTO, RAND_R_ALREADY_INSTANTIATED);
1074         return 0;
1075     }
1076     return random_set_string(&dgbl->rng_name, drbg)
1077         && random_set_string(&dgbl->rng_propq, propq)
1078         && random_set_string(&dgbl->rng_cipher, cipher)
1079         && random_set_string(&dgbl->rng_digest, digest);
1080 }
1081 
RAND_set_seed_source_type(OSSL_LIB_CTX * ctx,const char * seed,const char * propq)1082 int RAND_set_seed_source_type(OSSL_LIB_CTX *ctx, const char *seed,
1083                               const char *propq)
1084 {
1085     RAND_GLOBAL *dgbl = rand_get_global(ctx);
1086 
1087     if (dgbl == NULL)
1088         return 0;
1089     if (dgbl->seed != NULL) {
1090         ERR_raise(ERR_LIB_CRYPTO, RAND_R_ALREADY_INSTANTIATED);
1091         return 0;
1092     }
1093     return random_set_string(&dgbl->seed_name, seed)
1094         && random_set_string(&dgbl->seed_propq, propq);
1095 }
1096 
RAND_set1_random_provider(OSSL_LIB_CTX * ctx,OSSL_PROVIDER * prov)1097 int RAND_set1_random_provider(OSSL_LIB_CTX *ctx, OSSL_PROVIDER *prov)
1098 {
1099     RAND_GLOBAL *dgbl = rand_get_global(ctx);
1100 
1101     if (dgbl == NULL)
1102         return 0;
1103 
1104     if (prov == NULL) {
1105         OPENSSL_free(dgbl->random_provider_name);
1106         dgbl->random_provider_name = NULL;
1107         dgbl->random_provider = NULL;
1108         return 1;
1109     }
1110 
1111     if (dgbl->random_provider == prov)
1112         return 1;
1113 
1114     if (!set_random_provider_name(dgbl, OSSL_PROVIDER_get0_name(prov)))
1115         return 0;
1116 
1117     dgbl->random_provider = prov;
1118     return 1;
1119 }
1120 
1121 /*
1122  * When a new provider is loaded, we need to check to see if it is the
1123  * designated randomness provider and register it if it is.
1124  */
ossl_rand_check_random_provider_on_load(OSSL_LIB_CTX * ctx,OSSL_PROVIDER * prov)1125 int ossl_rand_check_random_provider_on_load(OSSL_LIB_CTX *ctx,
1126                                             OSSL_PROVIDER *prov)
1127 {
1128     RAND_GLOBAL *dgbl = rand_get_global(ctx);
1129 
1130     if (dgbl == NULL)
1131         return 0;
1132 
1133     /* No random provider name specified, or one is installed already */
1134     if (dgbl->random_provider_name == NULL || dgbl->random_provider != NULL)
1135         return 1;
1136 
1137     /* Does this provider match the name we're using? */
1138     if (strcmp(dgbl->random_provider_name, OSSL_PROVIDER_get0_name(prov)) != 0)
1139         return 1;
1140 
1141     dgbl->random_provider = prov;
1142     return 1;
1143 }
1144 
1145 /*
1146  * When a provider is being unloaded, if it is the randomness provider,
1147  * we need to deregister it.
1148  */
ossl_rand_check_random_provider_on_unload(OSSL_LIB_CTX * ctx,OSSL_PROVIDER * prov)1149 int ossl_rand_check_random_provider_on_unload(OSSL_LIB_CTX *ctx,
1150                                               OSSL_PROVIDER *prov)
1151 {
1152     RAND_GLOBAL *dgbl = rand_get_global(ctx);
1153 
1154     if (dgbl == NULL)
1155         return 0;
1156 
1157     if (dgbl->random_provider == prov)
1158         dgbl->random_provider = NULL;
1159     return 1;
1160 }
1161 
1162 #endif      /* !FIPS_MODULE */
1163