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12fb8c3d | 1 | /* |
3c7d0945 | 2 | * Copyright 2011-2018 The OpenSSL Project Authors. All Rights Reserved. |
12fb8c3d | 3 | * |
0db63de9 | 4 | * Licensed under the Apache License 2.0 (the "License"). You may not use |
12fb8c3d RS |
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 | #include <string.h> | |
11 | #include <openssl/crypto.h> | |
12 | #include <openssl/err.h> | |
13 | #include <openssl/rand.h> | |
14 | #include "rand_lcl.h" | |
0b14a5b7 KR |
15 | #include "internal/thread_once.h" |
16 | #include "internal/rand_int.h" | |
7caf122e | 17 | #include "internal/cryptlib_int.h" |
12fb8c3d RS |
18 | |
19 | /* | |
a73d990e DMSP |
20 | * Support framework for NIST SP 800-90A DRBG |
21 | * | |
22 | * See manual page RAND_DRBG(7) for a general overview. | |
75e2c877 | 23 | * |
12fb8c3d RS |
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.) | |
12fb8c3d RS |
30 | */ |
31 | ||
a73d990e | 32 | |
da0d114c MC |
33 | typedef struct drbg_global_st { |
34 | /* | |
35 | * The three shared DRBG instances | |
36 | * | |
37 | * There are three shared DRBG instances: <master>, <public>, and <private>. | |
38 | */ | |
a93ba405 | 39 | |
da0d114c MC |
40 | /* |
41 | * The <master> DRBG | |
42 | * | |
43 | * Not used directly by the application, only for reseeding the two other | |
44 | * DRBGs. It reseeds itself by pulling either randomness from os entropy | |
45 | * sources or by consuming randomness which was added by RAND_add(). | |
46 | * | |
47 | * The <master> DRBG is a global instance which is accessed concurrently by | |
48 | * all threads. The necessary locking is managed automatically by its child | |
49 | * DRBG instances during reseeding. | |
50 | */ | |
51 | RAND_DRBG *master_drbg; | |
52 | /* | |
53 | * The <public> DRBG | |
54 | * | |
55 | * Used by default for generating random bytes using RAND_bytes(). | |
56 | * | |
57 | * The <public> DRBG is thread-local, i.e., there is one instance per | |
58 | * thread. | |
59 | */ | |
60 | CRYPTO_THREAD_LOCAL public_drbg; | |
61 | /* | |
62 | * The <private> DRBG | |
63 | * | |
64 | * Used by default for generating private keys using RAND_priv_bytes() | |
65 | * | |
66 | * The <private> DRBG is thread-local, i.e., there is one instance per | |
67 | * thread. | |
68 | */ | |
69 | CRYPTO_THREAD_LOCAL private_drbg; | |
70 | } DRBG_GLOBAL; | |
a93ba405 | 71 | |
a2f27fd7 MC |
72 | typedef struct drbg_nonce_global_st { |
73 | CRYPTO_RWLOCK *rand_nonce_lock; | |
74 | int rand_nonce_count; | |
75 | } DRBG_NONCE_GLOBAL; | |
76 | ||
a93ba405 | 77 | /* NIST SP 800-90A DRBG recommends the use of a personalization string. */ |
d69226a3 | 78 | static const char ossl_pers_string[] = DRBG_DEFAULT_PERS_STRING; |
a93ba405 | 79 | |
8bf36651 SL |
80 | #define RAND_DRBG_TYPE_FLAGS ( \ |
81 | RAND_DRBG_FLAG_MASTER | RAND_DRBG_FLAG_PUBLIC | RAND_DRBG_FLAG_PRIVATE ) | |
82 | ||
83 | #define RAND_DRBG_TYPE_MASTER 0 | |
84 | #define RAND_DRBG_TYPE_PUBLIC 1 | |
85 | #define RAND_DRBG_TYPE_PRIVATE 2 | |
86 | ||
87 | /* Defaults */ | |
88 | static int rand_drbg_type[3] = { | |
89 | RAND_DRBG_TYPE, /* Master */ | |
90 | RAND_DRBG_TYPE, /* Public */ | |
91 | RAND_DRBG_TYPE /* Private */ | |
92 | }; | |
93 | static unsigned int rand_drbg_flags[3] = { | |
94 | RAND_DRBG_FLAGS | RAND_DRBG_FLAG_MASTER, /* Master */ | |
95 | RAND_DRBG_FLAGS | RAND_DRBG_FLAG_PUBLIC, /* Public */ | |
96 | RAND_DRBG_FLAGS | RAND_DRBG_FLAG_PRIVATE /* Private */ | |
97 | }; | |
31393fd9 | 98 | |
4917e911 DMSP |
99 | static unsigned int master_reseed_interval = MASTER_RESEED_INTERVAL; |
100 | static unsigned int slave_reseed_interval = SLAVE_RESEED_INTERVAL; | |
101 | ||
102 | static time_t master_reseed_time_interval = MASTER_RESEED_TIME_INTERVAL; | |
103 | static time_t slave_reseed_time_interval = SLAVE_RESEED_TIME_INTERVAL; | |
104 | ||
c402e943 DMSP |
105 | /* A logical OR of all used DRBG flag bits (currently there is only one) */ |
106 | static const unsigned int rand_drbg_used_flags = | |
8bf36651 SL |
107 | RAND_DRBG_FLAG_CTR_NO_DF | RAND_DRBG_FLAG_HMAC | RAND_DRBG_TYPE_FLAGS; |
108 | ||
c402e943 | 109 | |
da0d114c | 110 | static RAND_DRBG *drbg_setup(OPENSSL_CTX *ctx, RAND_DRBG *parent, int drbg_type); |
4f9dabbf | 111 | |
da0d114c MC |
112 | static RAND_DRBG *rand_drbg_new(OPENSSL_CTX *ctx, |
113 | int secure, | |
4f9dabbf DMSP |
114 | int type, |
115 | unsigned int flags, | |
116 | RAND_DRBG *parent); | |
0b14a5b7 | 117 | |
8bf36651 SL |
118 | static int is_ctr(int type) |
119 | { | |
120 | switch (type) { | |
121 | case NID_aes_128_ctr: | |
122 | case NID_aes_192_ctr: | |
123 | case NID_aes_256_ctr: | |
124 | return 1; | |
125 | default: | |
126 | return 0; | |
127 | } | |
128 | } | |
129 | ||
130 | static int is_digest(int type) | |
131 | { | |
132 | switch (type) { | |
133 | case NID_sha1: | |
134 | case NID_sha224: | |
135 | case NID_sha256: | |
136 | case NID_sha384: | |
137 | case NID_sha512: | |
138 | case NID_sha512_224: | |
139 | case NID_sha512_256: | |
140 | case NID_sha3_224: | |
141 | case NID_sha3_256: | |
142 | case NID_sha3_384: | |
143 | case NID_sha3_512: | |
144 | return 1; | |
145 | default: | |
146 | return 0; | |
147 | } | |
148 | } | |
149 | ||
a2f27fd7 MC |
150 | /* |
151 | * Initialize the OPENSSL_CTX global DRBGs on first use. | |
152 | * Returns the allocated global data on success or NULL on failure. | |
153 | */ | |
154 | static void *drbg_ossl_ctx_new(OPENSSL_CTX *libctx) | |
155 | { | |
156 | DRBG_GLOBAL *dgbl = OPENSSL_zalloc(sizeof(*dgbl)); | |
157 | ||
158 | if (dgbl == NULL) | |
159 | return NULL; | |
160 | ||
242f84d0 MC |
161 | #ifndef FIPS_MODE |
162 | /* | |
163 | * We need to ensure that base libcrypto thread handling has been | |
164 | * initialised. | |
165 | */ | |
166 | OPENSSL_init_crypto(0, NULL); | |
167 | #endif | |
168 | ||
a2f27fd7 MC |
169 | if (!CRYPTO_THREAD_init_local(&dgbl->private_drbg, NULL)) |
170 | goto err1; | |
171 | ||
172 | if (!CRYPTO_THREAD_init_local(&dgbl->public_drbg, NULL)) | |
173 | goto err2; | |
174 | ||
175 | dgbl->master_drbg = drbg_setup(libctx, NULL, RAND_DRBG_TYPE_MASTER); | |
176 | if (dgbl->master_drbg == NULL) | |
177 | goto err3; | |
178 | ||
179 | return dgbl; | |
180 | ||
181 | err3: | |
182 | CRYPTO_THREAD_cleanup_local(&dgbl->public_drbg); | |
183 | err2: | |
184 | CRYPTO_THREAD_cleanup_local(&dgbl->private_drbg); | |
185 | err1: | |
186 | OPENSSL_free(dgbl); | |
187 | return NULL; | |
188 | } | |
189 | ||
190 | static void drbg_ossl_ctx_free(void *vdgbl) | |
191 | { | |
192 | DRBG_GLOBAL *dgbl = vdgbl; | |
193 | ||
194 | RAND_DRBG_free(dgbl->master_drbg); | |
195 | CRYPTO_THREAD_cleanup_local(&dgbl->private_drbg); | |
196 | CRYPTO_THREAD_cleanup_local(&dgbl->public_drbg); | |
197 | ||
198 | OPENSSL_free(dgbl); | |
199 | } | |
200 | ||
201 | static const OPENSSL_CTX_METHOD drbg_ossl_ctx_method = { | |
202 | drbg_ossl_ctx_new, | |
203 | drbg_ossl_ctx_free, | |
204 | }; | |
205 | ||
206 | /* | |
207 | * drbg_ossl_ctx_new() calls drgb_setup() which calls rand_drbg_get_nonce() | |
208 | * which needs to get the rand_nonce_lock out of the OPENSSL_CTX...but since | |
209 | * drbg_ossl_ctx_new() hasn't finished running yet we need the rand_nonce_lock | |
210 | * to be in a different global data object. Otherwise we will go into an | |
211 | * infinite recursion loop. | |
212 | */ | |
213 | static void *drbg_nonce_ossl_ctx_new(OPENSSL_CTX *libctx) | |
214 | { | |
215 | DRBG_NONCE_GLOBAL *dngbl = OPENSSL_zalloc(sizeof(*dngbl)); | |
216 | ||
217 | if (dngbl == NULL) | |
218 | return NULL; | |
219 | ||
220 | dngbl->rand_nonce_lock = CRYPTO_THREAD_lock_new(); | |
221 | if (dngbl->rand_nonce_lock == NULL) { | |
222 | OPENSSL_free(dngbl); | |
223 | return NULL; | |
224 | } | |
225 | ||
226 | return dngbl; | |
227 | } | |
228 | ||
229 | static void drbg_nonce_ossl_ctx_free(void *vdngbl) | |
230 | { | |
231 | DRBG_NONCE_GLOBAL *dngbl = vdngbl; | |
232 | ||
233 | CRYPTO_THREAD_lock_free(dngbl->rand_nonce_lock); | |
234 | ||
235 | OPENSSL_free(dngbl); | |
236 | } | |
237 | ||
238 | static const OPENSSL_CTX_METHOD drbg_nonce_ossl_ctx_method = { | |
239 | drbg_nonce_ossl_ctx_new, | |
240 | drbg_nonce_ossl_ctx_free, | |
241 | }; | |
242 | ||
243 | static DRBG_GLOBAL *drbg_get_global(OPENSSL_CTX *libctx) | |
244 | { | |
245 | return openssl_ctx_get_data(libctx, OPENSSL_CTX_DRBG_INDEX, | |
246 | &drbg_ossl_ctx_method); | |
247 | } | |
248 | ||
249 | /* Implements the get_nonce() callback (see RAND_DRBG_set_callbacks()) */ | |
250 | size_t rand_drbg_get_nonce(RAND_DRBG *drbg, | |
251 | unsigned char **pout, | |
252 | int entropy, size_t min_len, size_t max_len) | |
253 | { | |
254 | size_t ret = 0; | |
255 | RAND_POOL *pool; | |
256 | DRBG_NONCE_GLOBAL *dngbl | |
257 | = openssl_ctx_get_data(drbg->libctx, OPENSSL_CTX_DRBG_NONCE_INDEX, | |
258 | &drbg_nonce_ossl_ctx_method); | |
259 | struct { | |
260 | void *instance; | |
261 | int count; | |
262 | } data; | |
263 | ||
264 | if (dngbl == NULL) | |
265 | return 0; | |
266 | ||
267 | memset(&data, 0, sizeof(data)); | |
268 | pool = rand_pool_new(0, min_len, max_len); | |
269 | if (pool == NULL) | |
270 | return 0; | |
271 | ||
272 | if (rand_pool_add_nonce_data(pool) == 0) | |
273 | goto err; | |
274 | ||
275 | data.instance = drbg; | |
276 | CRYPTO_atomic_add(&dngbl->rand_nonce_count, 1, &data.count, | |
277 | dngbl->rand_nonce_lock); | |
278 | ||
279 | if (rand_pool_add(pool, (unsigned char *)&data, sizeof(data), 0) == 0) | |
280 | goto err; | |
281 | ||
282 | ret = rand_pool_length(pool); | |
283 | *pout = rand_pool_detach(pool); | |
284 | ||
285 | err: | |
286 | rand_pool_free(pool); | |
287 | ||
288 | return ret; | |
289 | } | |
290 | ||
291 | /* | |
292 | * Implements the cleanup_nonce() callback (see RAND_DRBG_set_callbacks()) | |
293 | * | |
294 | */ | |
295 | void rand_drbg_cleanup_nonce(RAND_DRBG *drbg, | |
296 | unsigned char *out, size_t outlen) | |
297 | { | |
298 | OPENSSL_secure_clear_free(out, outlen); | |
299 | } | |
300 | ||
12fb8c3d | 301 | /* |
31393fd9 DMSP |
302 | * Set/initialize |drbg| to be of type |type|, with optional |flags|. |
303 | * | |
304 | * If |type| and |flags| are zero, use the defaults | |
efb8128a DMSP |
305 | * |
306 | * Returns 1 on success, 0 on failure. | |
12fb8c3d | 307 | */ |
31393fd9 | 308 | int RAND_DRBG_set(RAND_DRBG *drbg, int type, unsigned int flags) |
12fb8c3d RS |
309 | { |
310 | int ret = 1; | |
311 | ||
31393fd9 | 312 | if (type == 0 && flags == 0) { |
8bf36651 SL |
313 | type = rand_drbg_type[RAND_DRBG_TYPE_MASTER]; |
314 | flags = rand_drbg_flags[RAND_DRBG_TYPE_MASTER]; | |
315 | } | |
316 | ||
317 | /* If set is called multiple times - clear the old one */ | |
54f3e855 | 318 | if (drbg->type != 0 && (type != drbg->type || flags != drbg->flags)) { |
8bf36651 | 319 | drbg->meth->uninstantiate(drbg); |
54f3e855 BE |
320 | rand_pool_free(drbg->adin_pool); |
321 | drbg->adin_pool = NULL; | |
31393fd9 DMSP |
322 | } |
323 | ||
75e2c877 RS |
324 | drbg->state = DRBG_UNINITIALISED; |
325 | drbg->flags = flags; | |
31393fd9 | 326 | drbg->type = type; |
12fb8c3d | 327 | |
8bf36651 | 328 | if (type == 0) { |
12fb8c3d | 329 | /* Uninitialized; that's okay. */ |
54f3e855 | 330 | drbg->meth = NULL; |
12fb8c3d | 331 | return 1; |
8bf36651 | 332 | } else if (is_ctr(type)) { |
8212d505 | 333 | ret = drbg_ctr_init(drbg); |
8bf36651 SL |
334 | } else if (is_digest(type)) { |
335 | if (flags & RAND_DRBG_FLAG_HMAC) | |
336 | ret = drbg_hmac_init(drbg); | |
337 | else | |
338 | ret = drbg_hash_init(drbg); | |
339 | } else { | |
17209be8 BE |
340 | drbg->type = 0; |
341 | drbg->flags = 0; | |
342 | drbg->meth = NULL; | |
8bf36651 SL |
343 | RANDerr(RAND_F_RAND_DRBG_SET, RAND_R_UNSUPPORTED_DRBG_TYPE); |
344 | return 0; | |
12fb8c3d RS |
345 | } |
346 | ||
17209be8 BE |
347 | if (ret == 0) { |
348 | drbg->state = DRBG_ERROR; | |
12fb8c3d | 349 | RANDerr(RAND_F_RAND_DRBG_SET, RAND_R_ERROR_INITIALISING_DRBG); |
17209be8 | 350 | } |
12fb8c3d RS |
351 | return ret; |
352 | } | |
353 | ||
31393fd9 DMSP |
354 | /* |
355 | * Set/initialize default |type| and |flag| for new drbg instances. | |
356 | * | |
357 | * Returns 1 on success, 0 on failure. | |
358 | */ | |
359 | int RAND_DRBG_set_defaults(int type, unsigned int flags) | |
360 | { | |
8bf36651 SL |
361 | int all; |
362 | if (!(is_digest(type) || is_ctr(type))) { | |
31393fd9 DMSP |
363 | RANDerr(RAND_F_RAND_DRBG_SET_DEFAULTS, RAND_R_UNSUPPORTED_DRBG_TYPE); |
364 | return 0; | |
31393fd9 DMSP |
365 | } |
366 | ||
c402e943 | 367 | if ((flags & ~rand_drbg_used_flags) != 0) { |
31393fd9 DMSP |
368 | RANDerr(RAND_F_RAND_DRBG_SET_DEFAULTS, RAND_R_UNSUPPORTED_DRBG_FLAGS); |
369 | return 0; | |
370 | } | |
371 | ||
8bf36651 SL |
372 | all = ((flags & RAND_DRBG_TYPE_FLAGS) == 0); |
373 | if (all || (flags & RAND_DRBG_FLAG_MASTER) != 0) { | |
374 | rand_drbg_type[RAND_DRBG_TYPE_MASTER] = type; | |
375 | rand_drbg_flags[RAND_DRBG_TYPE_MASTER] = flags | RAND_DRBG_FLAG_MASTER; | |
376 | } | |
377 | if (all || (flags & RAND_DRBG_FLAG_PUBLIC) != 0) { | |
378 | rand_drbg_type[RAND_DRBG_TYPE_PUBLIC] = type; | |
379 | rand_drbg_flags[RAND_DRBG_TYPE_PUBLIC] = flags | RAND_DRBG_FLAG_PUBLIC; | |
380 | } | |
381 | if (all || (flags & RAND_DRBG_FLAG_PRIVATE) != 0) { | |
382 | rand_drbg_type[RAND_DRBG_TYPE_PRIVATE] = type; | |
383 | rand_drbg_flags[RAND_DRBG_TYPE_PRIVATE] = flags | RAND_DRBG_FLAG_PRIVATE; | |
384 | } | |
385 | return 1; | |
31393fd9 DMSP |
386 | } |
387 | ||
388 | ||
12fb8c3d | 389 | /* |
4f9dabbf DMSP |
390 | * Allocate memory and initialize a new DRBG. The DRBG is allocated on |
391 | * the secure heap if |secure| is nonzero and the secure heap is enabled. | |
392 | * The |parent|, if not NULL, will be used as random source for reseeding. | |
a93ba405 DMSP |
393 | * |
394 | * Returns a pointer to the new DRBG instance on success, NULL on failure. | |
12fb8c3d | 395 | */ |
da0d114c MC |
396 | static RAND_DRBG *rand_drbg_new(OPENSSL_CTX *ctx, |
397 | int secure, | |
4f9dabbf DMSP |
398 | int type, |
399 | unsigned int flags, | |
400 | RAND_DRBG *parent) | |
12fb8c3d | 401 | { |
b3d113ed P |
402 | RAND_DRBG *drbg = secure ? OPENSSL_secure_zalloc(sizeof(*drbg)) |
403 | : OPENSSL_zalloc(sizeof(*drbg)); | |
12fb8c3d | 404 | |
9d951a78 | 405 | if (drbg == NULL) { |
12fb8c3d | 406 | RANDerr(RAND_F_RAND_DRBG_NEW, ERR_R_MALLOC_FAILURE); |
f96ff4e9 | 407 | return NULL; |
12fb8c3d | 408 | } |
4f9dabbf | 409 | |
da0d114c | 410 | drbg->libctx = ctx; |
4f9dabbf | 411 | drbg->secure = secure && CRYPTO_secure_allocated(drbg); |
a35f607c | 412 | drbg->fork_count = rand_fork_count; |
75e2c877 | 413 | drbg->parent = parent; |
4917e911 DMSP |
414 | |
415 | if (parent == NULL) { | |
d69226a3 P |
416 | #ifdef FIPS_MODE |
417 | drbg->get_entropy = rand_crngt_get_entropy; | |
418 | drbg->cleanup_entropy = rand_crngt_cleanup_entropy; | |
419 | #else | |
5bc6bcf8 DMSP |
420 | drbg->get_entropy = rand_drbg_get_entropy; |
421 | drbg->cleanup_entropy = rand_drbg_cleanup_entropy; | |
d69226a3 | 422 | #endif |
5bc6bcf8 DMSP |
423 | #ifndef RAND_DRBG_GET_RANDOM_NONCE |
424 | drbg->get_nonce = rand_drbg_get_nonce; | |
425 | drbg->cleanup_nonce = rand_drbg_cleanup_nonce; | |
426 | #endif | |
427 | ||
4917e911 DMSP |
428 | drbg->reseed_interval = master_reseed_interval; |
429 | drbg->reseed_time_interval = master_reseed_time_interval; | |
430 | } else { | |
5bc6bcf8 DMSP |
431 | drbg->get_entropy = rand_drbg_get_entropy; |
432 | drbg->cleanup_entropy = rand_drbg_cleanup_entropy; | |
433 | /* | |
434 | * Do not provide nonce callbacks, the child DRBGs will | |
435 | * obtain their nonce using random bits from the parent. | |
436 | */ | |
437 | ||
4917e911 DMSP |
438 | drbg->reseed_interval = slave_reseed_interval; |
439 | drbg->reseed_time_interval = slave_reseed_time_interval; | |
440 | } | |
441 | ||
efb8128a | 442 | if (RAND_DRBG_set(drbg, type, flags) == 0) |
75e2c877 RS |
443 | goto err; |
444 | ||
7caf122e KR |
445 | if (parent != NULL) { |
446 | rand_drbg_lock(parent); | |
447 | if (drbg->strength > parent->strength) { | |
448 | /* | |
449 | * We currently don't support the algorithm from NIST SP 800-90C | |
450 | * 10.1.2 to use a weaker DRBG as source | |
451 | */ | |
452 | rand_drbg_unlock(parent); | |
453 | RANDerr(RAND_F_RAND_DRBG_NEW, RAND_R_PARENT_STRENGTH_TOO_WEAK); | |
454 | goto err; | |
455 | } | |
456 | rand_drbg_unlock(parent); | |
35503b7c KR |
457 | } |
458 | ||
75e2c877 RS |
459 | return drbg; |
460 | ||
c2e33a05 | 461 | err: |
c5e0b3a6 | 462 | RAND_DRBG_free(drbg); |
4f9dabbf | 463 | |
75e2c877 | 464 | return NULL; |
12fb8c3d RS |
465 | } |
466 | ||
da0d114c MC |
467 | RAND_DRBG *RAND_DRBG_new_ex(OPENSSL_CTX *ctx, int type, unsigned int flags, |
468 | RAND_DRBG *parent) | |
469 | { | |
470 | return rand_drbg_new(ctx, 0, type, flags, parent); | |
471 | } | |
472 | ||
4f9dabbf DMSP |
473 | RAND_DRBG *RAND_DRBG_new(int type, unsigned int flags, RAND_DRBG *parent) |
474 | { | |
da0d114c | 475 | return RAND_DRBG_new_ex(NULL, type, flags, parent); |
4f9dabbf DMSP |
476 | } |
477 | ||
da0d114c MC |
478 | RAND_DRBG *RAND_DRBG_secure_new_ex(OPENSSL_CTX *ctx, int type, |
479 | unsigned int flags, RAND_DRBG *parent) | |
4f9dabbf | 480 | { |
da0d114c | 481 | return rand_drbg_new(ctx, 1, type, flags, parent); |
4f9dabbf DMSP |
482 | } |
483 | ||
da0d114c MC |
484 | RAND_DRBG *RAND_DRBG_secure_new(int type, unsigned int flags, RAND_DRBG *parent) |
485 | { | |
486 | return RAND_DRBG_secure_new_ex(NULL, type, flags, parent); | |
487 | } | |
12fb8c3d | 488 | /* |
75e2c877 | 489 | * Uninstantiate |drbg| and free all memory. |
12fb8c3d | 490 | */ |
75e2c877 | 491 | void RAND_DRBG_free(RAND_DRBG *drbg) |
12fb8c3d | 492 | { |
c16de9d8 | 493 | if (drbg == NULL) |
12fb8c3d RS |
494 | return; |
495 | ||
8212d505 DMSP |
496 | if (drbg->meth != NULL) |
497 | drbg->meth->uninstantiate(drbg); | |
54f3e855 | 498 | rand_pool_free(drbg->adin_pool); |
4f9dabbf | 499 | CRYPTO_THREAD_lock_free(drbg->lock); |
75e2c877 | 500 | CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DRBG, drbg, &drbg->ex_data); |
4f9dabbf DMSP |
501 | |
502 | if (drbg->secure) | |
503 | OPENSSL_secure_clear_free(drbg, sizeof(*drbg)); | |
504 | else | |
505 | OPENSSL_clear_free(drbg, sizeof(*drbg)); | |
12fb8c3d RS |
506 | } |
507 | ||
508 | /* | |
75e2c877 | 509 | * Instantiate |drbg|, after it has been initialized. Use |pers| and |
12fb8c3d | 510 | * |perslen| as prediction-resistance input. |
2139145b BK |
511 | * |
512 | * Requires that drbg->lock is already locked for write, if non-null. | |
efb8128a DMSP |
513 | * |
514 | * Returns 1 on success, 0 on failure. | |
12fb8c3d | 515 | */ |
75e2c877 | 516 | int RAND_DRBG_instantiate(RAND_DRBG *drbg, |
12fb8c3d RS |
517 | const unsigned char *pers, size_t perslen) |
518 | { | |
12fb8c3d | 519 | unsigned char *nonce = NULL, *entropy = NULL; |
aa048aef | 520 | size_t noncelen = 0, entropylen = 0; |
2a70d65b KR |
521 | size_t min_entropy = drbg->strength; |
522 | size_t min_entropylen = drbg->min_entropylen; | |
523 | size_t max_entropylen = drbg->max_entropylen; | |
12fb8c3d | 524 | |
aa048aef | 525 | if (perslen > drbg->max_perslen) { |
75e2c877 RS |
526 | RANDerr(RAND_F_RAND_DRBG_INSTANTIATE, |
527 | RAND_R_PERSONALISATION_STRING_TOO_LONG); | |
12fb8c3d RS |
528 | goto end; |
529 | } | |
8212d505 | 530 | |
272c0df8 | 531 | if (drbg->meth == NULL) { |
8212d505 DMSP |
532 | RANDerr(RAND_F_RAND_DRBG_INSTANTIATE, |
533 | RAND_R_NO_DRBG_IMPLEMENTATION_SELECTED); | |
534 | goto end; | |
535 | } | |
536 | ||
75e2c877 RS |
537 | if (drbg->state != DRBG_UNINITIALISED) { |
538 | RANDerr(RAND_F_RAND_DRBG_INSTANTIATE, | |
539 | drbg->state == DRBG_ERROR ? RAND_R_IN_ERROR_STATE | |
540 | : RAND_R_ALREADY_INSTANTIATED); | |
12fb8c3d RS |
541 | goto end; |
542 | } | |
543 | ||
75e2c877 | 544 | drbg->state = DRBG_ERROR; |
2a70d65b KR |
545 | |
546 | /* | |
547 | * NIST SP800-90Ar1 section 9.1 says you can combine getting the entropy | |
548 | * and nonce in 1 call by increasing the entropy with 50% and increasing | |
549 | * the minimum length to accomadate the length of the nonce. | |
550 | * We do this in case a nonce is require and get_nonce is NULL. | |
551 | */ | |
552 | if (drbg->min_noncelen > 0 && drbg->get_nonce == NULL) { | |
553 | min_entropy += drbg->strength / 2; | |
554 | min_entropylen += drbg->min_noncelen; | |
555 | max_entropylen += drbg->max_noncelen; | |
556 | } | |
557 | ||
a83dc59a BE |
558 | drbg->reseed_next_counter = tsan_load(&drbg->reseed_prop_counter); |
559 | if (drbg->reseed_next_counter) { | |
560 | drbg->reseed_next_counter++; | |
561 | if(!drbg->reseed_next_counter) | |
562 | drbg->reseed_next_counter = 1; | |
563 | } | |
564 | ||
75e2c877 | 565 | if (drbg->get_entropy != NULL) |
2a70d65b KR |
566 | entropylen = drbg->get_entropy(drbg, &entropy, min_entropy, |
567 | min_entropylen, max_entropylen, 0); | |
568 | if (entropylen < min_entropylen | |
c2e33a05 | 569 | || entropylen > max_entropylen) { |
75e2c877 | 570 | RANDerr(RAND_F_RAND_DRBG_INSTANTIATE, RAND_R_ERROR_RETRIEVING_ENTROPY); |
12fb8c3d RS |
571 | goto end; |
572 | } | |
573 | ||
2a70d65b | 574 | if (drbg->min_noncelen > 0 && drbg->get_nonce != NULL) { |
75e2c877 | 575 | noncelen = drbg->get_nonce(drbg, &nonce, drbg->strength / 2, |
aa048aef DMSP |
576 | drbg->min_noncelen, drbg->max_noncelen); |
577 | if (noncelen < drbg->min_noncelen || noncelen > drbg->max_noncelen) { | |
2a70d65b | 578 | RANDerr(RAND_F_RAND_DRBG_INSTANTIATE, RAND_R_ERROR_RETRIEVING_NONCE); |
12fb8c3d RS |
579 | goto end; |
580 | } | |
581 | } | |
582 | ||
8212d505 | 583 | if (!drbg->meth->instantiate(drbg, entropy, entropylen, |
12fb8c3d | 584 | nonce, noncelen, pers, perslen)) { |
75e2c877 | 585 | RANDerr(RAND_F_RAND_DRBG_INSTANTIATE, RAND_R_ERROR_INSTANTIATING_DRBG); |
12fb8c3d RS |
586 | goto end; |
587 | } | |
588 | ||
75e2c877 | 589 | drbg->state = DRBG_READY; |
8bf36651 | 590 | drbg->reseed_gen_counter = 1; |
08a65d96 | 591 | drbg->reseed_time = time(NULL); |
a83dc59a | 592 | tsan_store(&drbg->reseed_prop_counter, drbg->reseed_next_counter); |
12fb8c3d | 593 | |
c2e33a05 | 594 | end: |
75e2c877 | 595 | if (entropy != NULL && drbg->cleanup_entropy != NULL) |
6969a3f4 | 596 | drbg->cleanup_entropy(drbg, entropy, entropylen); |
c2e33a05 | 597 | if (nonce != NULL && drbg->cleanup_nonce != NULL) |
6969a3f4 | 598 | drbg->cleanup_nonce(drbg, nonce, noncelen); |
75e2c877 | 599 | if (drbg->state == DRBG_READY) |
12fb8c3d | 600 | return 1; |
12fb8c3d RS |
601 | return 0; |
602 | } | |
603 | ||
604 | /* | |
75e2c877 | 605 | * Uninstantiate |drbg|. Must be instantiated before it can be used. |
2139145b BK |
606 | * |
607 | * Requires that drbg->lock is already locked for write, if non-null. | |
efb8128a DMSP |
608 | * |
609 | * Returns 1 on success, 0 on failure. | |
12fb8c3d | 610 | */ |
75e2c877 | 611 | int RAND_DRBG_uninstantiate(RAND_DRBG *drbg) |
12fb8c3d | 612 | { |
8bf36651 | 613 | int index = -1, type, flags; |
272c0df8 | 614 | if (drbg->meth == NULL) { |
fb9c3ff5 | 615 | drbg->state = DRBG_ERROR; |
8212d505 DMSP |
616 | RANDerr(RAND_F_RAND_DRBG_UNINSTANTIATE, |
617 | RAND_R_NO_DRBG_IMPLEMENTATION_SELECTED); | |
618 | return 0; | |
619 | } | |
620 | ||
efb8128a DMSP |
621 | /* Clear the entire drbg->ctr struct, then reset some important |
622 | * members of the drbg->ctr struct (e.g. keysize, df_ks) to their | |
623 | * initial values. | |
624 | */ | |
8212d505 | 625 | drbg->meth->uninstantiate(drbg); |
8bf36651 SL |
626 | |
627 | /* The reset uses the default values for type and flags */ | |
628 | if (drbg->flags & RAND_DRBG_FLAG_MASTER) | |
629 | index = RAND_DRBG_TYPE_MASTER; | |
630 | else if (drbg->flags & RAND_DRBG_FLAG_PRIVATE) | |
631 | index = RAND_DRBG_TYPE_PRIVATE; | |
632 | else if (drbg->flags & RAND_DRBG_FLAG_PUBLIC) | |
633 | index = RAND_DRBG_TYPE_PUBLIC; | |
634 | ||
635 | if (index != -1) { | |
636 | flags = rand_drbg_flags[index]; | |
637 | type = rand_drbg_type[index]; | |
638 | } else { | |
639 | flags = drbg->flags; | |
640 | type = drbg->type; | |
641 | } | |
642 | return RAND_DRBG_set(drbg, type, flags); | |
12fb8c3d RS |
643 | } |
644 | ||
645 | /* | |
c16de9d8 | 646 | * Reseed |drbg|, mixing in the specified data |
2139145b BK |
647 | * |
648 | * Requires that drbg->lock is already locked for write, if non-null. | |
efb8128a DMSP |
649 | * |
650 | * Returns 1 on success, 0 on failure. | |
12fb8c3d | 651 | */ |
75e2c877 | 652 | int RAND_DRBG_reseed(RAND_DRBG *drbg, |
eb238134 KR |
653 | const unsigned char *adin, size_t adinlen, |
654 | int prediction_resistance) | |
12fb8c3d RS |
655 | { |
656 | unsigned char *entropy = NULL; | |
aa048aef | 657 | size_t entropylen = 0; |
75e2c877 RS |
658 | |
659 | if (drbg->state == DRBG_ERROR) { | |
660 | RANDerr(RAND_F_RAND_DRBG_RESEED, RAND_R_IN_ERROR_STATE); | |
661 | return 0; | |
662 | } | |
663 | if (drbg->state == DRBG_UNINITIALISED) { | |
664 | RANDerr(RAND_F_RAND_DRBG_RESEED, RAND_R_NOT_INSTANTIATED); | |
665 | return 0; | |
12fb8c3d RS |
666 | } |
667 | ||
272c0df8 | 668 | if (adin == NULL) { |
12fb8c3d | 669 | adinlen = 0; |
272c0df8 | 670 | } else if (adinlen > drbg->max_adinlen) { |
75e2c877 RS |
671 | RANDerr(RAND_F_RAND_DRBG_RESEED, RAND_R_ADDITIONAL_INPUT_TOO_LONG); |
672 | return 0; | |
12fb8c3d RS |
673 | } |
674 | ||
75e2c877 | 675 | drbg->state = DRBG_ERROR; |
a83dc59a BE |
676 | |
677 | drbg->reseed_next_counter = tsan_load(&drbg->reseed_prop_counter); | |
678 | if (drbg->reseed_next_counter) { | |
679 | drbg->reseed_next_counter++; | |
680 | if(!drbg->reseed_next_counter) | |
681 | drbg->reseed_next_counter = 1; | |
682 | } | |
683 | ||
75e2c877 | 684 | if (drbg->get_entropy != NULL) |
aa048aef | 685 | entropylen = drbg->get_entropy(drbg, &entropy, drbg->strength, |
eb238134 KR |
686 | drbg->min_entropylen, |
687 | drbg->max_entropylen, | |
688 | prediction_resistance); | |
c16de9d8 | 689 | if (entropylen < drbg->min_entropylen |
c2e33a05 | 690 | || entropylen > drbg->max_entropylen) { |
75e2c877 | 691 | RANDerr(RAND_F_RAND_DRBG_RESEED, RAND_R_ERROR_RETRIEVING_ENTROPY); |
12fb8c3d RS |
692 | goto end; |
693 | } | |
694 | ||
8212d505 | 695 | if (!drbg->meth->reseed(drbg, entropy, entropylen, adin, adinlen)) |
12fb8c3d | 696 | goto end; |
a93ba405 | 697 | |
75e2c877 | 698 | drbg->state = DRBG_READY; |
8bf36651 | 699 | drbg->reseed_gen_counter = 1; |
08a65d96 | 700 | drbg->reseed_time = time(NULL); |
a83dc59a | 701 | tsan_store(&drbg->reseed_prop_counter, drbg->reseed_next_counter); |
12fb8c3d | 702 | |
c2e33a05 | 703 | end: |
75e2c877 | 704 | if (entropy != NULL && drbg->cleanup_entropy != NULL) |
6969a3f4 | 705 | drbg->cleanup_entropy(drbg, entropy, entropylen); |
75e2c877 | 706 | if (drbg->state == DRBG_READY) |
12fb8c3d | 707 | return 1; |
12fb8c3d RS |
708 | return 0; |
709 | } | |
710 | ||
c16de9d8 DMSP |
711 | /* |
712 | * Restart |drbg|, using the specified entropy or additional input | |
713 | * | |
714 | * Tries its best to get the drbg instantiated by all means, | |
715 | * regardless of its current state. | |
716 | * | |
717 | * Optionally, a |buffer| of |len| random bytes can be passed, | |
718 | * which is assumed to contain at least |entropy| bits of entropy. | |
719 | * | |
720 | * If |entropy| > 0, the buffer content is used as entropy input. | |
721 | * | |
722 | * If |entropy| == 0, the buffer content is used as additional input | |
723 | * | |
724 | * Returns 1 on success, 0 on failure. | |
725 | * | |
726 | * This function is used internally only. | |
727 | */ | |
728 | int rand_drbg_restart(RAND_DRBG *drbg, | |
729 | const unsigned char *buffer, size_t len, size_t entropy) | |
730 | { | |
731 | int reseeded = 0; | |
732 | const unsigned char *adin = NULL; | |
733 | size_t adinlen = 0; | |
734 | ||
31f32abb | 735 | if (drbg->seed_pool != NULL) { |
c16de9d8 | 736 | RANDerr(RAND_F_RAND_DRBG_RESTART, ERR_R_INTERNAL_ERROR); |
3064b551 | 737 | drbg->state = DRBG_ERROR; |
31f32abb BE |
738 | rand_pool_free(drbg->seed_pool); |
739 | drbg->seed_pool = NULL; | |
3064b551 | 740 | return 0; |
c16de9d8 DMSP |
741 | } |
742 | ||
743 | if (buffer != NULL) { | |
744 | if (entropy > 0) { | |
745 | if (drbg->max_entropylen < len) { | |
746 | RANDerr(RAND_F_RAND_DRBG_RESTART, | |
747 | RAND_R_ENTROPY_INPUT_TOO_LONG); | |
3064b551 | 748 | drbg->state = DRBG_ERROR; |
c16de9d8 DMSP |
749 | return 0; |
750 | } | |
751 | ||
752 | if (entropy > 8 * len) { | |
753 | RANDerr(RAND_F_RAND_DRBG_RESTART, RAND_R_ENTROPY_OUT_OF_RANGE); | |
3064b551 | 754 | drbg->state = DRBG_ERROR; |
c16de9d8 DMSP |
755 | return 0; |
756 | } | |
757 | ||
758 | /* will be picked up by the rand_drbg_get_entropy() callback */ | |
31f32abb BE |
759 | drbg->seed_pool = rand_pool_attach(buffer, len, entropy); |
760 | if (drbg->seed_pool == NULL) | |
c16de9d8 | 761 | return 0; |
c16de9d8 DMSP |
762 | } else { |
763 | if (drbg->max_adinlen < len) { | |
764 | RANDerr(RAND_F_RAND_DRBG_RESTART, | |
765 | RAND_R_ADDITIONAL_INPUT_TOO_LONG); | |
3064b551 | 766 | drbg->state = DRBG_ERROR; |
c16de9d8 DMSP |
767 | return 0; |
768 | } | |
769 | adin = buffer; | |
770 | adinlen = len; | |
771 | } | |
772 | } | |
773 | ||
774 | /* repair error state */ | |
efb8128a | 775 | if (drbg->state == DRBG_ERROR) |
c16de9d8 DMSP |
776 | RAND_DRBG_uninstantiate(drbg); |
777 | ||
778 | /* repair uninitialized state */ | |
779 | if (drbg->state == DRBG_UNINITIALISED) { | |
a93ba405 DMSP |
780 | /* reinstantiate drbg */ |
781 | RAND_DRBG_instantiate(drbg, | |
782 | (const unsigned char *) ossl_pers_string, | |
783 | sizeof(ossl_pers_string) - 1); | |
c16de9d8 DMSP |
784 | /* already reseeded. prevent second reseeding below */ |
785 | reseeded = (drbg->state == DRBG_READY); | |
786 | } | |
787 | ||
788 | /* refresh current state if entropy or additional input has been provided */ | |
789 | if (drbg->state == DRBG_READY) { | |
790 | if (adin != NULL) { | |
791 | /* | |
792 | * mix in additional input without reseeding | |
793 | * | |
794 | * Similar to RAND_DRBG_reseed(), but the provided additional | |
795 | * data |adin| is mixed into the current state without pulling | |
796 | * entropy from the trusted entropy source using get_entropy(). | |
797 | * This is not a reseeding in the strict sense of NIST SP 800-90A. | |
798 | */ | |
8212d505 | 799 | drbg->meth->reseed(drbg, adin, adinlen, NULL, 0); |
c16de9d8 DMSP |
800 | } else if (reseeded == 0) { |
801 | /* do a full reseeding if it has not been done yet above */ | |
eb238134 | 802 | RAND_DRBG_reseed(drbg, NULL, 0, 0); |
c16de9d8 DMSP |
803 | } |
804 | } | |
805 | ||
31f32abb BE |
806 | rand_pool_free(drbg->seed_pool); |
807 | drbg->seed_pool = NULL; | |
c16de9d8 DMSP |
808 | |
809 | return drbg->state == DRBG_READY; | |
810 | } | |
811 | ||
12fb8c3d RS |
812 | /* |
813 | * Generate |outlen| bytes into the buffer at |out|. Reseed if we need | |
814 | * to or if |prediction_resistance| is set. Additional input can be | |
815 | * sent in |adin| and |adinlen|. | |
c16de9d8 | 816 | * |
2139145b BK |
817 | * Requires that drbg->lock is already locked for write, if non-null. |
818 | * | |
c16de9d8 DMSP |
819 | * Returns 1 on success, 0 on failure. |
820 | * | |
12fb8c3d | 821 | */ |
75e2c877 | 822 | int RAND_DRBG_generate(RAND_DRBG *drbg, unsigned char *out, size_t outlen, |
12fb8c3d RS |
823 | int prediction_resistance, |
824 | const unsigned char *adin, size_t adinlen) | |
825 | { | |
e0b625f9 DMSP |
826 | int reseed_required = 0; |
827 | ||
c16de9d8 DMSP |
828 | if (drbg->state != DRBG_READY) { |
829 | /* try to recover from previous errors */ | |
830 | rand_drbg_restart(drbg, NULL, 0, 0); | |
831 | ||
832 | if (drbg->state == DRBG_ERROR) { | |
833 | RANDerr(RAND_F_RAND_DRBG_GENERATE, RAND_R_IN_ERROR_STATE); | |
834 | return 0; | |
835 | } | |
836 | if (drbg->state == DRBG_UNINITIALISED) { | |
837 | RANDerr(RAND_F_RAND_DRBG_GENERATE, RAND_R_NOT_INSTANTIATED); | |
838 | return 0; | |
839 | } | |
12fb8c3d | 840 | } |
c16de9d8 | 841 | |
75e2c877 RS |
842 | if (outlen > drbg->max_request) { |
843 | RANDerr(RAND_F_RAND_DRBG_GENERATE, RAND_R_REQUEST_TOO_LARGE_FOR_DRBG); | |
844 | return 0; | |
845 | } | |
aa048aef | 846 | if (adinlen > drbg->max_adinlen) { |
75e2c877 RS |
847 | RANDerr(RAND_F_RAND_DRBG_GENERATE, RAND_R_ADDITIONAL_INPUT_TOO_LONG); |
848 | return 0; | |
12fb8c3d RS |
849 | } |
850 | ||
a35f607c RS |
851 | if (drbg->fork_count != rand_fork_count) { |
852 | drbg->fork_count = rand_fork_count; | |
e0b625f9 | 853 | reseed_required = 1; |
a35f607c RS |
854 | } |
855 | ||
a93ba405 | 856 | if (drbg->reseed_interval > 0) { |
8bf36651 | 857 | if (drbg->reseed_gen_counter > drbg->reseed_interval) |
a93ba405 DMSP |
858 | reseed_required = 1; |
859 | } | |
08a65d96 DMSP |
860 | if (drbg->reseed_time_interval > 0) { |
861 | time_t now = time(NULL); | |
862 | if (now < drbg->reseed_time | |
863 | || now - drbg->reseed_time >= drbg->reseed_time_interval) | |
864 | reseed_required = 1; | |
865 | } | |
a83dc59a BE |
866 | if (drbg->parent != NULL) { |
867 | unsigned int reseed_counter = tsan_load(&drbg->reseed_prop_counter); | |
868 | if (reseed_counter > 0 | |
869 | && tsan_load(&drbg->parent->reseed_prop_counter) | |
870 | != reseed_counter) | |
a93ba405 DMSP |
871 | reseed_required = 1; |
872 | } | |
12fb8c3d | 873 | |
e0b625f9 | 874 | if (reseed_required || prediction_resistance) { |
eb238134 | 875 | if (!RAND_DRBG_reseed(drbg, adin, adinlen, prediction_resistance)) { |
75e2c877 RS |
876 | RANDerr(RAND_F_RAND_DRBG_GENERATE, RAND_R_RESEED_ERROR); |
877 | return 0; | |
12fb8c3d RS |
878 | } |
879 | adin = NULL; | |
880 | adinlen = 0; | |
881 | } | |
882 | ||
8212d505 | 883 | if (!drbg->meth->generate(drbg, out, outlen, adin, adinlen)) { |
75e2c877 RS |
884 | drbg->state = DRBG_ERROR; |
885 | RANDerr(RAND_F_RAND_DRBG_GENERATE, RAND_R_GENERATE_ERROR); | |
886 | return 0; | |
12fb8c3d | 887 | } |
75e2c877 | 888 | |
8bf36651 | 889 | drbg->reseed_gen_counter++; |
e0b625f9 | 890 | |
12fb8c3d | 891 | return 1; |
12fb8c3d RS |
892 | } |
893 | ||
20928ff6 KR |
894 | /* |
895 | * Generates |outlen| random bytes and stores them in |out|. It will | |
896 | * using the given |drbg| to generate the bytes. | |
897 | * | |
898 | * Requires that drbg->lock is already locked for write, if non-null. | |
899 | * | |
900 | * Returns 1 on success 0 on failure. | |
901 | */ | |
902 | int RAND_DRBG_bytes(RAND_DRBG *drbg, unsigned char *out, size_t outlen) | |
903 | { | |
904 | unsigned char *additional = NULL; | |
905 | size_t additional_len; | |
1648338b | 906 | size_t chunk; |
54f3e855 | 907 | size_t ret = 0; |
20928ff6 | 908 | |
54f3e855 BE |
909 | if (drbg->adin_pool == NULL) { |
910 | if (drbg->type == 0) | |
911 | goto err; | |
912 | drbg->adin_pool = rand_pool_new(0, 0, drbg->max_adinlen); | |
913 | if (drbg->adin_pool == NULL) | |
914 | goto err; | |
915 | } | |
916 | ||
917 | additional_len = rand_drbg_get_additional_data(drbg->adin_pool, | |
918 | &additional); | |
1648338b DMSP |
919 | |
920 | for ( ; outlen > 0; outlen -= chunk, out += chunk) { | |
921 | chunk = outlen; | |
922 | if (chunk > drbg->max_request) | |
923 | chunk = drbg->max_request; | |
924 | ret = RAND_DRBG_generate(drbg, out, chunk, 0, additional, additional_len); | |
925 | if (!ret) | |
926 | goto err; | |
927 | } | |
928 | ret = 1; | |
929 | ||
54f3e855 BE |
930 | err: |
931 | if (additional != NULL) | |
932 | rand_drbg_cleanup_additional_data(drbg->adin_pool, additional); | |
20928ff6 KR |
933 | |
934 | return ret; | |
935 | } | |
936 | ||
12fb8c3d | 937 | /* |
c16de9d8 DMSP |
938 | * Set the RAND_DRBG callbacks for obtaining entropy and nonce. |
939 | * | |
a73d990e DMSP |
940 | * Setting the callbacks is allowed only if the drbg has not been |
941 | * initialized yet. Otherwise, the operation will fail. | |
c16de9d8 | 942 | * |
a73d990e | 943 | * Returns 1 on success, 0 on failure. |
12fb8c3d | 944 | */ |
75e2c877 | 945 | int RAND_DRBG_set_callbacks(RAND_DRBG *drbg, |
c16de9d8 DMSP |
946 | RAND_DRBG_get_entropy_fn get_entropy, |
947 | RAND_DRBG_cleanup_entropy_fn cleanup_entropy, | |
948 | RAND_DRBG_get_nonce_fn get_nonce, | |
949 | RAND_DRBG_cleanup_nonce_fn cleanup_nonce) | |
12fb8c3d | 950 | { |
a83dc59a BE |
951 | if (drbg->state != DRBG_UNINITIALISED |
952 | || drbg->parent != NULL) | |
12fb8c3d | 953 | return 0; |
c16de9d8 DMSP |
954 | drbg->get_entropy = get_entropy; |
955 | drbg->cleanup_entropy = cleanup_entropy; | |
956 | drbg->get_nonce = get_nonce; | |
957 | drbg->cleanup_nonce = cleanup_nonce; | |
12fb8c3d RS |
958 | return 1; |
959 | } | |
960 | ||
961 | /* | |
75e2c877 | 962 | * Set the reseed interval. |
a93ba405 DMSP |
963 | * |
964 | * The drbg will reseed automatically whenever the number of generate | |
965 | * requests exceeds the given reseed interval. If the reseed interval | |
08a65d96 | 966 | * is 0, then this feature is disabled. |
a93ba405 DMSP |
967 | * |
968 | * Returns 1 on success, 0 on failure. | |
12fb8c3d | 969 | */ |
a93ba405 | 970 | int RAND_DRBG_set_reseed_interval(RAND_DRBG *drbg, unsigned int interval) |
12fb8c3d | 971 | { |
a93ba405 | 972 | if (interval > MAX_RESEED_INTERVAL) |
4c75ee85 | 973 | return 0; |
75e2c877 | 974 | drbg->reseed_interval = interval; |
4c75ee85 | 975 | return 1; |
12fb8c3d RS |
976 | } |
977 | ||
08a65d96 DMSP |
978 | /* |
979 | * Set the reseed time interval. | |
980 | * | |
981 | * The drbg will reseed automatically whenever the time elapsed since | |
982 | * the last reseeding exceeds the given reseed time interval. For safety, | |
983 | * a reseeding will also occur if the clock has been reset to a smaller | |
984 | * value. | |
985 | * | |
986 | * Returns 1 on success, 0 on failure. | |
987 | */ | |
988 | int RAND_DRBG_set_reseed_time_interval(RAND_DRBG *drbg, time_t interval) | |
989 | { | |
990 | if (interval > MAX_RESEED_TIME_INTERVAL) | |
991 | return 0; | |
992 | drbg->reseed_time_interval = interval; | |
993 | return 1; | |
994 | } | |
995 | ||
4917e911 DMSP |
996 | /* |
997 | * Set the default values for reseed (time) intervals of new DRBG instances | |
998 | * | |
999 | * The default values can be set independently for master DRBG instances | |
1000 | * (without a parent) and slave DRBG instances (with parent). | |
1001 | * | |
1002 | * Returns 1 on success, 0 on failure. | |
1003 | */ | |
1004 | ||
1005 | int RAND_DRBG_set_reseed_defaults( | |
1006 | unsigned int _master_reseed_interval, | |
1007 | unsigned int _slave_reseed_interval, | |
1008 | time_t _master_reseed_time_interval, | |
1009 | time_t _slave_reseed_time_interval | |
1010 | ) | |
1011 | { | |
1012 | if (_master_reseed_interval > MAX_RESEED_INTERVAL | |
1013 | || _slave_reseed_interval > MAX_RESEED_INTERVAL) | |
1014 | return 0; | |
1015 | ||
1016 | if (_master_reseed_time_interval > MAX_RESEED_TIME_INTERVAL | |
1017 | || _slave_reseed_time_interval > MAX_RESEED_TIME_INTERVAL) | |
1018 | return 0; | |
1019 | ||
1020 | master_reseed_interval = _master_reseed_interval; | |
1021 | slave_reseed_interval = _slave_reseed_interval; | |
1022 | ||
1023 | master_reseed_time_interval = _master_reseed_time_interval; | |
1024 | slave_reseed_time_interval = _slave_reseed_time_interval; | |
1025 | ||
1026 | return 1; | |
1027 | } | |
3ce1c27b DMSP |
1028 | |
1029 | /* | |
1030 | * Locks the given drbg. Locking a drbg which does not have locking | |
1031 | * enabled is considered a successful no-op. | |
1032 | * | |
1033 | * Returns 1 on success, 0 on failure. | |
1034 | */ | |
812b1537 | 1035 | int rand_drbg_lock(RAND_DRBG *drbg) |
3ce1c27b DMSP |
1036 | { |
1037 | if (drbg->lock != NULL) | |
1038 | return CRYPTO_THREAD_write_lock(drbg->lock); | |
1039 | ||
1040 | return 1; | |
1041 | } | |
1042 | ||
1043 | /* | |
1044 | * Unlocks the given drbg. Unlocking a drbg which does not have locking | |
1045 | * enabled is considered a successful no-op. | |
1046 | * | |
1047 | * Returns 1 on success, 0 on failure. | |
1048 | */ | |
812b1537 | 1049 | int rand_drbg_unlock(RAND_DRBG *drbg) |
3ce1c27b DMSP |
1050 | { |
1051 | if (drbg->lock != NULL) | |
1052 | return CRYPTO_THREAD_unlock(drbg->lock); | |
1053 | ||
1054 | return 1; | |
1055 | } | |
1056 | ||
1057 | /* | |
1058 | * Enables locking for the given drbg | |
1059 | * | |
1060 | * Locking can only be enabled if the random generator | |
1061 | * is in the uninitialized state. | |
1062 | * | |
1063 | * Returns 1 on success, 0 on failure. | |
1064 | */ | |
812b1537 | 1065 | int rand_drbg_enable_locking(RAND_DRBG *drbg) |
3ce1c27b DMSP |
1066 | { |
1067 | if (drbg->state != DRBG_UNINITIALISED) { | |
1068 | RANDerr(RAND_F_RAND_DRBG_ENABLE_LOCKING, | |
1069 | RAND_R_DRBG_ALREADY_INITIALIZED); | |
1070 | return 0; | |
1071 | } | |
1072 | ||
1073 | if (drbg->lock == NULL) { | |
4f9dabbf | 1074 | if (drbg->parent != NULL && drbg->parent->lock == NULL) { |
3ce1c27b DMSP |
1075 | RANDerr(RAND_F_RAND_DRBG_ENABLE_LOCKING, |
1076 | RAND_R_PARENT_LOCKING_NOT_ENABLED); | |
1077 | return 0; | |
1078 | } | |
1079 | ||
1080 | drbg->lock = CRYPTO_THREAD_lock_new(); | |
1081 | if (drbg->lock == NULL) { | |
1082 | RANDerr(RAND_F_RAND_DRBG_ENABLE_LOCKING, | |
1083 | RAND_R_FAILED_TO_CREATE_LOCK); | |
1084 | return 0; | |
1085 | } | |
1086 | } | |
1087 | ||
1088 | return 1; | |
1089 | } | |
1090 | ||
12fb8c3d RS |
1091 | /* |
1092 | * Get and set the EXDATA | |
1093 | */ | |
75e2c877 RS |
1094 | int RAND_DRBG_set_ex_data(RAND_DRBG *drbg, int idx, void *arg) |
1095 | { | |
1096 | return CRYPTO_set_ex_data(&drbg->ex_data, idx, arg); | |
1097 | } | |
1098 | ||
1099 | void *RAND_DRBG_get_ex_data(const RAND_DRBG *drbg, int idx) | |
1100 | { | |
1101 | return CRYPTO_get_ex_data(&drbg->ex_data, idx); | |
1102 | } | |
1103 | ||
1104 | ||
1105 | /* | |
1106 | * The following functions provide a RAND_METHOD that works on the | |
1107 | * global DRBG. They lock. | |
1108 | */ | |
1109 | ||
0b14a5b7 | 1110 | /* |
933033b6 DMSP |
1111 | * Allocates a new global DRBG on the secure heap (if enabled) and |
1112 | * initializes it with default settings. | |
a93ba405 DMSP |
1113 | * |
1114 | * Returns a pointer to the new DRBG instance on success, NULL on failure. | |
0b14a5b7 | 1115 | */ |
da0d114c | 1116 | static RAND_DRBG *drbg_setup(OPENSSL_CTX *ctx, RAND_DRBG *parent, int drbg_type) |
0b14a5b7 | 1117 | { |
933033b6 | 1118 | RAND_DRBG *drbg; |
0b14a5b7 | 1119 | |
da0d114c MC |
1120 | drbg = RAND_DRBG_secure_new_ex(ctx, rand_drbg_type[drbg_type], |
1121 | rand_drbg_flags[drbg_type], parent); | |
933033b6 DMSP |
1122 | if (drbg == NULL) |
1123 | return NULL; | |
1124 | ||
7caf122e KR |
1125 | /* Only the master DRBG needs to have a lock */ |
1126 | if (parent == NULL && rand_drbg_enable_locking(drbg) == 0) | |
933033b6 | 1127 | goto err; |
a93ba405 | 1128 | |
a93ba405 | 1129 | /* enable seed propagation */ |
a83dc59a | 1130 | tsan_store(&drbg->reseed_prop_counter, 1); |
a93ba405 | 1131 | |
c16de9d8 | 1132 | /* |
43687d68 | 1133 | * Ignore instantiation error to support just-in-time instantiation. |
c16de9d8 DMSP |
1134 | * |
1135 | * The state of the drbg will be checked in RAND_DRBG_generate() and | |
1136 | * an automatic recovery is attempted. | |
1137 | */ | |
43687d68 DMSP |
1138 | (void)RAND_DRBG_instantiate(drbg, |
1139 | (const unsigned char *) ossl_pers_string, | |
1140 | sizeof(ossl_pers_string) - 1); | |
933033b6 DMSP |
1141 | return drbg; |
1142 | ||
1143 | err: | |
4f9dabbf | 1144 | RAND_DRBG_free(drbg); |
933033b6 | 1145 | return NULL; |
0b14a5b7 KR |
1146 | } |
1147 | ||
242f84d0 | 1148 | static void drbg_delete_thread_state(OPENSSL_CTX *ctx) |
7caf122e | 1149 | { |
da0d114c | 1150 | DRBG_GLOBAL *dgbl = drbg_get_global(ctx); |
7caf122e KR |
1151 | RAND_DRBG *drbg; |
1152 | ||
da0d114c MC |
1153 | if (dgbl == NULL) |
1154 | return; | |
1155 | drbg = CRYPTO_THREAD_get_local(&dgbl->public_drbg); | |
1156 | CRYPTO_THREAD_set_local(&dgbl->public_drbg, NULL); | |
7caf122e KR |
1157 | RAND_DRBG_free(drbg); |
1158 | ||
da0d114c MC |
1159 | drbg = CRYPTO_THREAD_get_local(&dgbl->private_drbg); |
1160 | CRYPTO_THREAD_set_local(&dgbl->private_drbg, NULL); | |
7caf122e | 1161 | RAND_DRBG_free(drbg); |
0b14a5b7 KR |
1162 | } |
1163 | ||
c16de9d8 | 1164 | /* Implements the default OpenSSL RAND_bytes() method */ |
75e2c877 RS |
1165 | static int drbg_bytes(unsigned char *out, int count) |
1166 | { | |
f61f62ea | 1167 | int ret; |
a93ba405 | 1168 | RAND_DRBG *drbg = RAND_DRBG_get0_public(); |
75e2c877 | 1169 | |
0b14a5b7 KR |
1170 | if (drbg == NULL) |
1171 | return 0; | |
1172 | ||
f61f62ea | 1173 | ret = RAND_DRBG_bytes(drbg, out, count); |
f61f62ea | 1174 | |
75e2c877 RS |
1175 | return ret; |
1176 | } | |
1177 | ||
8817215d DMSP |
1178 | /* |
1179 | * Calculates the minimum length of a full entropy buffer | |
1180 | * which is necessary to seed (i.e. instantiate) the DRBG | |
1181 | * successfully. | |
8817215d | 1182 | */ |
1c615e4c | 1183 | size_t rand_drbg_seedlen(RAND_DRBG *drbg) |
8817215d DMSP |
1184 | { |
1185 | /* | |
1186 | * If no os entropy source is available then RAND_seed(buffer, bufsize) | |
1187 | * is expected to succeed if and only if the buffer length satisfies | |
1188 | * the following requirements, which follow from the calculations | |
1189 | * in RAND_DRBG_instantiate(). | |
1190 | */ | |
1191 | size_t min_entropy = drbg->strength; | |
1192 | size_t min_entropylen = drbg->min_entropylen; | |
1193 | ||
1194 | /* | |
1195 | * Extra entropy for the random nonce in the absence of a | |
1196 | * get_nonce callback, see comment in RAND_DRBG_instantiate(). | |
1197 | */ | |
1198 | if (drbg->min_noncelen > 0 && drbg->get_nonce == NULL) { | |
1199 | min_entropy += drbg->strength / 2; | |
1200 | min_entropylen += drbg->min_noncelen; | |
1201 | } | |
1202 | ||
1203 | /* | |
1204 | * Convert entropy requirement from bits to bytes | |
1205 | * (dividing by 8 without rounding upwards, because | |
1206 | * all entropy requirements are divisible by 8). | |
1207 | */ | |
1208 | min_entropy >>= 3; | |
1209 | ||
1210 | /* Return a value that satisfies both requirements */ | |
1211 | return min_entropy > min_entropylen ? min_entropy : min_entropylen; | |
1212 | } | |
1213 | ||
c16de9d8 | 1214 | /* Implements the default OpenSSL RAND_add() method */ |
75e2c877 RS |
1215 | static int drbg_add(const void *buf, int num, double randomness) |
1216 | { | |
c16de9d8 | 1217 | int ret = 0; |
a93ba405 | 1218 | RAND_DRBG *drbg = RAND_DRBG_get0_master(); |
8817215d | 1219 | size_t buflen; |
59f90557 | 1220 | size_t seedlen; |
75e2c877 | 1221 | |
c16de9d8 DMSP |
1222 | if (drbg == NULL) |
1223 | return 0; | |
75e2c877 | 1224 | |
c16de9d8 DMSP |
1225 | if (num < 0 || randomness < 0.0) |
1226 | return 0; | |
75e2c877 | 1227 | |
4011bab1 | 1228 | rand_drbg_lock(drbg); |
59f90557 DMSP |
1229 | seedlen = rand_drbg_seedlen(drbg); |
1230 | ||
8817215d DMSP |
1231 | buflen = (size_t)num; |
1232 | ||
3a50a8a9 DMSP |
1233 | #ifdef FIPS_MODE |
1234 | /* | |
1235 | * NIST SP-800-90A mandates that entropy *shall not* be provided | |
1236 | * by the consuming application. By setting the randomness to zero, | |
1237 | * we ensure that the buffer contents will be added to the internal | |
1238 | * state of the DRBG only as additional data. | |
1239 | * | |
1240 | * (NIST SP-800-90Ar1, Sections 9.1 and 9.2) | |
1241 | */ | |
1242 | randomness = 0.0; | |
1243 | #endif | |
8817215d DMSP |
1244 | if (buflen < seedlen || randomness < (double) seedlen) { |
1245 | #if defined(OPENSSL_RAND_SEED_NONE) | |
1246 | /* | |
1247 | * If no os entropy source is available, a reseeding will fail | |
1248 | * inevitably. So we use a trick to mix the buffer contents into | |
1249 | * the DRBG state without forcing a reseeding: we generate a | |
1250 | * dummy random byte, using the buffer content as additional data. | |
4011bab1 | 1251 | * Note: This won't work with RAND_DRBG_FLAG_CTR_NO_DF. |
8817215d DMSP |
1252 | */ |
1253 | unsigned char dummy[1]; | |
1254 | ||
4011bab1 BE |
1255 | ret = RAND_DRBG_generate(drbg, dummy, sizeof(dummy), 0, buf, buflen); |
1256 | rand_drbg_unlock(drbg); | |
1257 | return ret; | |
8817215d DMSP |
1258 | #else |
1259 | /* | |
3a50a8a9 | 1260 | * If an os entropy source is available then we declare the buffer content |
8817215d DMSP |
1261 | * as additional data by setting randomness to zero and trigger a regular |
1262 | * reseeding. | |
1263 | */ | |
1264 | randomness = 0.0; | |
1265 | #endif | |
1266 | } | |
1267 | ||
8817215d | 1268 | if (randomness > (double)seedlen) { |
c16de9d8 DMSP |
1269 | /* |
1270 | * The purpose of this check is to bound |randomness| by a | |
1271 | * relatively small value in order to prevent an integer | |
1272 | * overflow when multiplying by 8 in the rand_drbg_restart() | |
3064b551 DMSP |
1273 | * call below. Note that randomness is measured in bytes, |
1274 | * not bits, so this value corresponds to eight times the | |
1275 | * security strength. | |
c16de9d8 | 1276 | */ |
8817215d | 1277 | randomness = (double)seedlen; |
75e2c877 RS |
1278 | } |
1279 | ||
8817215d | 1280 | ret = rand_drbg_restart(drbg, buf, buflen, (size_t)(8 * randomness)); |
812b1537 | 1281 | rand_drbg_unlock(drbg); |
c16de9d8 DMSP |
1282 | |
1283 | return ret; | |
75e2c877 RS |
1284 | } |
1285 | ||
c16de9d8 | 1286 | /* Implements the default OpenSSL RAND_seed() method */ |
75e2c877 RS |
1287 | static int drbg_seed(const void *buf, int num) |
1288 | { | |
1289 | return drbg_add(buf, num, num); | |
1290 | } | |
1291 | ||
c16de9d8 | 1292 | /* Implements the default OpenSSL RAND_status() method */ |
75e2c877 | 1293 | static int drbg_status(void) |
12fb8c3d | 1294 | { |
75e2c877 | 1295 | int ret; |
a93ba405 | 1296 | RAND_DRBG *drbg = RAND_DRBG_get0_master(); |
0b14a5b7 KR |
1297 | |
1298 | if (drbg == NULL) | |
1299 | return 0; | |
75e2c877 | 1300 | |
812b1537 | 1301 | rand_drbg_lock(drbg); |
0b14a5b7 | 1302 | ret = drbg->state == DRBG_READY ? 1 : 0; |
812b1537 | 1303 | rand_drbg_unlock(drbg); |
75e2c877 | 1304 | return ret; |
12fb8c3d RS |
1305 | } |
1306 | ||
0b14a5b7 | 1307 | /* |
a93ba405 DMSP |
1308 | * Get the master DRBG. |
1309 | * Returns pointer to the DRBG on success, NULL on failure. | |
1310 | * | |
1311 | */ | |
da0d114c | 1312 | RAND_DRBG *OPENSSL_CTX_get0_master_drbg(OPENSSL_CTX *ctx) |
a93ba405 | 1313 | { |
da0d114c MC |
1314 | DRBG_GLOBAL *dgbl = drbg_get_global(ctx); |
1315 | ||
1316 | if (dgbl == NULL) | |
a93ba405 DMSP |
1317 | return NULL; |
1318 | ||
da0d114c MC |
1319 | return dgbl->master_drbg; |
1320 | } | |
1321 | ||
1322 | RAND_DRBG *RAND_DRBG_get0_master(void) | |
1323 | { | |
1324 | return OPENSSL_CTX_get0_master_drbg(NULL); | |
a93ba405 DMSP |
1325 | } |
1326 | ||
1327 | /* | |
1328 | * Get the public DRBG. | |
0b14a5b7 KR |
1329 | * Returns pointer to the DRBG on success, NULL on failure. |
1330 | */ | |
da0d114c | 1331 | RAND_DRBG *OPENSSL_CTX_get0_public_drbg(OPENSSL_CTX *ctx) |
0b14a5b7 | 1332 | { |
da0d114c | 1333 | DRBG_GLOBAL *dgbl = drbg_get_global(ctx); |
7caf122e KR |
1334 | RAND_DRBG *drbg; |
1335 | ||
da0d114c | 1336 | if (dgbl == NULL) |
0b14a5b7 KR |
1337 | return NULL; |
1338 | ||
da0d114c | 1339 | drbg = CRYPTO_THREAD_get_local(&dgbl->public_drbg); |
7caf122e | 1340 | if (drbg == NULL) { |
242f84d0 | 1341 | if (!ossl_init_thread_start(NULL, drbg_delete_thread_state)) |
272c0df8 | 1342 | return NULL; |
da0d114c MC |
1343 | drbg = drbg_setup(ctx, dgbl->master_drbg, RAND_DRBG_TYPE_PUBLIC); |
1344 | CRYPTO_THREAD_set_local(&dgbl->public_drbg, drbg); | |
7caf122e KR |
1345 | } |
1346 | return drbg; | |
0b14a5b7 KR |
1347 | } |
1348 | ||
da0d114c MC |
1349 | RAND_DRBG *RAND_DRBG_get0_public(void) |
1350 | { | |
1351 | return OPENSSL_CTX_get0_public_drbg(NULL); | |
1352 | } | |
1353 | ||
0b14a5b7 | 1354 | /* |
a93ba405 | 1355 | * Get the private DRBG. |
0b14a5b7 KR |
1356 | * Returns pointer to the DRBG on success, NULL on failure. |
1357 | */ | |
da0d114c | 1358 | RAND_DRBG *OPENSSL_CTX_get0_private_drbg(OPENSSL_CTX *ctx) |
0b14a5b7 | 1359 | { |
da0d114c | 1360 | DRBG_GLOBAL *dgbl = drbg_get_global(ctx); |
7caf122e KR |
1361 | RAND_DRBG *drbg; |
1362 | ||
da0d114c | 1363 | if (dgbl == NULL) |
0b14a5b7 KR |
1364 | return NULL; |
1365 | ||
da0d114c | 1366 | drbg = CRYPTO_THREAD_get_local(&dgbl->private_drbg); |
7caf122e | 1367 | if (drbg == NULL) { |
242f84d0 | 1368 | if (!ossl_init_thread_start(NULL, drbg_delete_thread_state)) |
272c0df8 | 1369 | return NULL; |
da0d114c MC |
1370 | drbg = drbg_setup(ctx, dgbl->master_drbg, RAND_DRBG_TYPE_PRIVATE); |
1371 | CRYPTO_THREAD_set_local(&dgbl->private_drbg, drbg); | |
7caf122e KR |
1372 | } |
1373 | return drbg; | |
0b14a5b7 KR |
1374 | } |
1375 | ||
da0d114c MC |
1376 | RAND_DRBG *RAND_DRBG_get0_private(void) |
1377 | { | |
1378 | return OPENSSL_CTX_get0_private_drbg(NULL); | |
1379 | } | |
1380 | ||
75e2c877 RS |
1381 | RAND_METHOD rand_meth = { |
1382 | drbg_seed, | |
1383 | drbg_bytes, | |
ddc6a5c8 | 1384 | NULL, |
75e2c877 RS |
1385 | drbg_add, |
1386 | drbg_bytes, | |
1387 | drbg_status | |
1388 | }; | |
1389 | ||
1390 | RAND_METHOD *RAND_OpenSSL(void) | |
12fb8c3d | 1391 | { |
a2f27fd7 | 1392 | #ifndef FIPS_MODE |
75e2c877 | 1393 | return &rand_meth; |
a2f27fd7 MC |
1394 | #else |
1395 | return NULL; | |
1396 | #endif | |
12fb8c3d | 1397 | } |