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1 /* crypto/rand/md_rand.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3 * All rights reserved.
4 *
5 * This package is an SSL implementation written
6 * by Eric Young (eay@cryptsoft.com).
7 * The implementation was written so as to conform with Netscapes SSL.
8 *
9 * This library is free for commercial and non-commercial use as long as
10 * the following conditions are aheared to. The following conditions
11 * apply to all code found in this distribution, be it the RC4, RSA,
12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
13 * included with this distribution is covered by the same copyright terms
14 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15 *
16 * Copyright remains Eric Young's, and as such any Copyright notices in
17 * the code are not to be removed.
18 * If this package is used in a product, Eric Young should be given attribution
19 * as the author of the parts of the library used.
20 * This can be in the form of a textual message at program startup or
21 * in documentation (online or textual) provided with the package.
22 *
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
25 * are met:
26 * 1. Redistributions of source code must retain the copyright
27 * notice, this list of conditions and the following disclaimer.
28 * 2. Redistributions in binary form must reproduce the above copyright
29 * notice, this list of conditions and the following disclaimer in the
30 * documentation and/or other materials provided with the distribution.
31 * 3. All advertising materials mentioning features or use of this software
32 * must display the following acknowledgement:
33 * "This product includes cryptographic software written by
34 * Eric Young (eay@cryptsoft.com)"
35 * The word 'cryptographic' can be left out if the rouines from the library
36 * being used are not cryptographic related :-).
37 * 4. If you include any Windows specific code (or a derivative thereof) from
38 * the apps directory (application code) you must include an acknowledgement:
39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40 *
41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51 * SUCH DAMAGE.
52 *
53 * The licence and distribution terms for any publically available version or
54 * derivative of this code cannot be changed. i.e. this code cannot simply be
55 * copied and put under another distribution licence
56 * [including the GNU Public Licence.]
57 */
58 /* ====================================================================
59 * Copyright (c) 1998-2001 The OpenSSL Project. All rights reserved.
60 *
61 * Redistribution and use in source and binary forms, with or without
62 * modification, are permitted provided that the following conditions
63 * are met:
64 *
65 * 1. Redistributions of source code must retain the above copyright
66 * notice, this list of conditions and the following disclaimer.
67 *
68 * 2. Redistributions in binary form must reproduce the above copyright
69 * notice, this list of conditions and the following disclaimer in
70 * the documentation and/or other materials provided with the
71 * distribution.
72 *
73 * 3. All advertising materials mentioning features or use of this
74 * software must display the following acknowledgment:
75 * "This product includes software developed by the OpenSSL Project
76 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
77 *
78 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
79 * endorse or promote products derived from this software without
80 * prior written permission. For written permission, please contact
81 * openssl-core@openssl.org.
82 *
83 * 5. Products derived from this software may not be called "OpenSSL"
84 * nor may "OpenSSL" appear in their names without prior written
85 * permission of the OpenSSL Project.
86 *
87 * 6. Redistributions of any form whatsoever must retain the following
88 * acknowledgment:
89 * "This product includes software developed by the OpenSSL Project
90 * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
91 *
92 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
93 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
94 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
95 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
96 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
97 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
98 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
99 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
100 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
101 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
102 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
103 * OF THE POSSIBILITY OF SUCH DAMAGE.
104 * ====================================================================
105 *
106 * This product includes cryptographic software written by Eric Young
107 * (eay@cryptsoft.com). This product includes software written by Tim
108 * Hudson (tjh@cryptsoft.com).
109 *
110 */
111
112 #define OPENSSL_FIPSEVP
113
114 #ifdef MD_RAND_DEBUG
115 # ifndef NDEBUG
116 # define NDEBUG
117 # endif
118 #endif
119
120 #include <assert.h>
121 #include <stdio.h>
122 #include <string.h>
123
124 #include "e_os.h"
125
126 #include <openssl/crypto.h>
127 #include <openssl/rand.h>
128 #include "rand_lcl.h"
129
130 #include <openssl/err.h>
131
132 #ifdef BN_DEBUG
133 # define PREDICT
134 #endif
135
136 /* #define PREDICT 1 */
137
138 #define STATE_SIZE 1023
139 static size_t state_num = 0, state_index = 0;
140 static unsigned char state[STATE_SIZE + MD_DIGEST_LENGTH];
141 static unsigned char md[MD_DIGEST_LENGTH];
142 static long md_count[2] = { 0, 0 };
143
144 static double entropy = 0;
145 static int initialized = 0;
146
147 static unsigned int crypto_lock_rand = 0; /* may be set only when a thread
148 * holds CRYPTO_LOCK_RAND (to
149 * prevent double locking) */
150 /* access to lockin_thread is synchronized by CRYPTO_LOCK_RAND2 */
151 /* valid iff crypto_lock_rand is set */
152 static CRYPTO_THREADID locking_threadid;
153
154 #ifdef PREDICT
155 int rand_predictable = 0;
156 #endif
157
158 const char RAND_version[] = "RAND" OPENSSL_VERSION_PTEXT;
159
160 static void ssleay_rand_cleanup(void);
161 static void ssleay_rand_seed(const void *buf, int num);
162 static void ssleay_rand_add(const void *buf, int num, double add_entropy);
163 static int ssleay_rand_nopseudo_bytes(unsigned char *buf, int num);
164 static int ssleay_rand_pseudo_bytes(unsigned char *buf, int num);
165 static int ssleay_rand_status(void);
166
167 RAND_METHOD rand_ssleay_meth = {
168 ssleay_rand_seed,
169 ssleay_rand_nopseudo_bytes,
170 ssleay_rand_cleanup,
171 ssleay_rand_add,
172 ssleay_rand_pseudo_bytes,
173 ssleay_rand_status
174 };
175
176 RAND_METHOD *RAND_SSLeay(void)
177 {
178 return (&rand_ssleay_meth);
179 }
180
181 static void ssleay_rand_cleanup(void)
182 {
183 OPENSSL_cleanse(state, sizeof(state));
184 state_num = 0;
185 state_index = 0;
186 OPENSSL_cleanse(md, MD_DIGEST_LENGTH);
187 md_count[0] = 0;
188 md_count[1] = 0;
189 entropy = 0;
190 initialized = 0;
191 }
192
193 static void ssleay_rand_add(const void *buf, int num, double add)
194 {
195 int i, j, k, st_idx;
196 long md_c[2];
197 unsigned char local_md[MD_DIGEST_LENGTH];
198 EVP_MD_CTX m;
199 int do_not_lock;
200
201 if (!num)
202 return;
203
204 /*
205 * (Based on the rand(3) manpage)
206 *
207 * The input is chopped up into units of 20 bytes (or less for
208 * the last block). Each of these blocks is run through the hash
209 * function as follows: The data passed to the hash function
210 * is the current 'md', the same number of bytes from the 'state'
211 * (the location determined by in incremented looping index) as
212 * the current 'block', the new key data 'block', and 'count'
213 * (which is incremented after each use).
214 * The result of this is kept in 'md' and also xored into the
215 * 'state' at the same locations that were used as input into the
216 * hash function.
217 */
218
219 /* check if we already have the lock */
220 if (crypto_lock_rand) {
221 CRYPTO_THREADID cur;
222 CRYPTO_THREADID_current(&cur);
223 CRYPTO_r_lock(CRYPTO_LOCK_RAND2);
224 do_not_lock = !CRYPTO_THREADID_cmp(&locking_threadid, &cur);
225 CRYPTO_r_unlock(CRYPTO_LOCK_RAND2);
226 } else
227 do_not_lock = 0;
228
229 if (!do_not_lock)
230 CRYPTO_w_lock(CRYPTO_LOCK_RAND);
231 st_idx = state_index;
232
233 /*
234 * use our own copies of the counters so that even if a concurrent thread
235 * seeds with exactly the same data and uses the same subarray there's
236 * _some_ difference
237 */
238 md_c[0] = md_count[0];
239 md_c[1] = md_count[1];
240
241 memcpy(local_md, md, sizeof(md));
242
243 /* state_index <= state_num <= STATE_SIZE */
244 state_index += num;
245 if (state_index >= STATE_SIZE) {
246 state_index %= STATE_SIZE;
247 state_num = STATE_SIZE;
248 } else if (state_num < STATE_SIZE) {
249 if (state_index > state_num)
250 state_num = state_index;
251 }
252 /* state_index <= state_num <= STATE_SIZE */
253
254 /*
255 * state[st_idx], ..., state[(st_idx + num - 1) % STATE_SIZE] are what we
256 * will use now, but other threads may use them as well
257 */
258
259 md_count[1] += (num / MD_DIGEST_LENGTH) + (num % MD_DIGEST_LENGTH > 0);
260
261 if (!do_not_lock)
262 CRYPTO_w_unlock(CRYPTO_LOCK_RAND);
263
264 EVP_MD_CTX_init(&m);
265 for (i = 0; i < num; i += MD_DIGEST_LENGTH) {
266 j = (num - i);
267 j = (j > MD_DIGEST_LENGTH) ? MD_DIGEST_LENGTH : j;
268
269 if (!MD_Init(&m) ||
270 !MD_Update(&m, local_md, MD_DIGEST_LENGTH))
271 goto err;
272 k = (st_idx + j) - STATE_SIZE;
273 if (k > 0) {
274 if (!MD_Update(&m, &(state[st_idx]), j - k) ||
275 !MD_Update(&m, &(state[0]), k))
276 goto err;
277 } else
278 if (!MD_Update(&m, &(state[st_idx]), j))
279 goto err;
280
281 /* DO NOT REMOVE THE FOLLOWING CALL TO MD_Update()! */
282 if (!MD_Update(&m, buf, j))
283 goto err;
284 /*
285 * We know that line may cause programs such as purify and valgrind
286 * to complain about use of uninitialized data. The problem is not,
287 * it's with the caller. Removing that line will make sure you get
288 * really bad randomness and thereby other problems such as very
289 * insecure keys.
290 */
291
292 if (!MD_Update(&m, (unsigned char *)&(md_c[0]), sizeof(md_c)) ||
293 !MD_Final(&m, local_md))
294 goto err;
295 md_c[1]++;
296
297 buf = (const char *)buf + j;
298
299 for (k = 0; k < j; k++) {
300 /*
301 * Parallel threads may interfere with this, but always each byte
302 * of the new state is the XOR of some previous value of its and
303 * local_md (itermediate values may be lost). Alway using locking
304 * could hurt performance more than necessary given that
305 * conflicts occur only when the total seeding is longer than the
306 * random state.
307 */
308 state[st_idx++] ^= local_md[k];
309 if (st_idx >= STATE_SIZE)
310 st_idx = 0;
311 }
312 }
313
314 if (!do_not_lock)
315 CRYPTO_w_lock(CRYPTO_LOCK_RAND);
316 /*
317 * Don't just copy back local_md into md -- this could mean that other
318 * thread's seeding remains without effect (except for the incremented
319 * counter). By XORing it we keep at least as much entropy as fits into
320 * md.
321 */
322 for (k = 0; k < (int)sizeof(md); k++) {
323 md[k] ^= local_md[k];
324 }
325 if (entropy < ENTROPY_NEEDED) /* stop counting when we have enough */
326 entropy += add;
327 if (!do_not_lock)
328 CRYPTO_w_unlock(CRYPTO_LOCK_RAND);
329
330 #if !defined(OPENSSL_THREADS) && !defined(OPENSSL_SYS_WIN32)
331 assert(md_c[1] == md_count[1]);
332 #endif
333
334 err:
335 EVP_MD_CTX_cleanup(&m);
336 }
337
338 static void ssleay_rand_seed(const void *buf, int num)
339 {
340 ssleay_rand_add(buf, num, (double)num);
341 }
342
343 int ssleay_rand_bytes(unsigned char *buf, int num, int pseudo, int lock)
344 {
345 static volatile int stirred_pool = 0;
346 int i, j, k;
347 size_t num_ceil, st_idx, st_num;
348 long md_c[2];
349 unsigned char local_md[MD_DIGEST_LENGTH];
350 EVP_MD_CTX m;
351 #ifndef GETPID_IS_MEANINGLESS
352 pid_t curr_pid = getpid();
353 #endif
354 int do_stir_pool = 0;
355
356 #ifdef PREDICT
357 if (rand_predictable) {
358 static unsigned char val = 0;
359
360 for (i = 0; i < num; i++)
361 buf[i] = val++;
362 return (1);
363 }
364 #endif
365
366 if (num <= 0)
367 return 1;
368
369 EVP_MD_CTX_init(&m);
370 /* round upwards to multiple of MD_DIGEST_LENGTH/2 */
371 num_ceil =
372 (1 + (num - 1) / (MD_DIGEST_LENGTH / 2)) * (MD_DIGEST_LENGTH / 2);
373
374 /*
375 * (Based on the rand(3) manpage:)
376 *
377 * For each group of 10 bytes (or less), we do the following:
378 *
379 * Input into the hash function the local 'md' (which is initialized from
380 * the global 'md' before any bytes are generated), the bytes that are to
381 * be overwritten by the random bytes, and bytes from the 'state'
382 * (incrementing looping index). From this digest output (which is kept
383 * in 'md'), the top (up to) 10 bytes are returned to the caller and the
384 * bottom 10 bytes are xored into the 'state'.
385 *
386 * Finally, after we have finished 'num' random bytes for the
387 * caller, 'count' (which is incremented) and the local and global 'md'
388 * are fed into the hash function and the results are kept in the
389 * global 'md'.
390 */
391 if (lock)
392 CRYPTO_w_lock(CRYPTO_LOCK_RAND);
393
394 /* prevent ssleay_rand_bytes() from trying to obtain the lock again */
395 CRYPTO_w_lock(CRYPTO_LOCK_RAND2);
396 CRYPTO_THREADID_current(&locking_threadid);
397 CRYPTO_w_unlock(CRYPTO_LOCK_RAND2);
398 crypto_lock_rand = 1;
399
400 if (!initialized) {
401 RAND_poll();
402 initialized = (entropy >= ENTROPY_NEEDED);
403 }
404
405 if (!stirred_pool)
406 do_stir_pool = 1;
407
408 if (!initialized) {
409 /*
410 * If the PRNG state is not yet unpredictable, then seeing the PRNG
411 * output may help attackers to determine the new state; thus we have
412 * to decrease the entropy estimate. Once we've had enough initial
413 * seeding we don't bother to adjust the entropy count, though,
414 * because we're not ambitious to provide *information-theoretic*
415 * randomness. NOTE: This approach fails if the program forks before
416 * we have enough entropy. Entropy should be collected in a separate
417 * input pool and be transferred to the output pool only when the
418 * entropy limit has been reached.
419 */
420 entropy -= num;
421 if (entropy < 0)
422 entropy = 0;
423 }
424
425 if (do_stir_pool) {
426 /*
427 * In the output function only half of 'md' remains secret, so we
428 * better make sure that the required entropy gets 'evenly
429 * distributed' through 'state', our randomness pool. The input
430 * function (ssleay_rand_add) chains all of 'md', which makes it more
431 * suitable for this purpose.
432 */
433
434 int n = STATE_SIZE; /* so that the complete pool gets accessed */
435 while (n > 0) {
436 #if MD_DIGEST_LENGTH > 20
437 # error "Please adjust DUMMY_SEED."
438 #endif
439 #define DUMMY_SEED "...................." /* at least MD_DIGEST_LENGTH */
440 /*
441 * Note that the seed does not matter, it's just that
442 * ssleay_rand_add expects to have something to hash.
443 */
444 ssleay_rand_add(DUMMY_SEED, MD_DIGEST_LENGTH, 0.0);
445 n -= MD_DIGEST_LENGTH;
446 }
447 if (initialized)
448 stirred_pool = 1;
449 }
450
451 st_idx = state_index;
452 st_num = state_num;
453 md_c[0] = md_count[0];
454 md_c[1] = md_count[1];
455 memcpy(local_md, md, sizeof(md));
456
457 state_index += num_ceil;
458 if (state_index > state_num)
459 state_index %= state_num;
460
461 /*
462 * state[st_idx], ..., state[(st_idx + num_ceil - 1) % st_num] are now
463 * ours (but other threads may use them too)
464 */
465
466 md_count[0] += 1;
467
468 /* before unlocking, we must clear 'crypto_lock_rand' */
469 crypto_lock_rand = 0;
470 if (lock)
471 CRYPTO_w_unlock(CRYPTO_LOCK_RAND);
472
473 while (num > 0) {
474 /* num_ceil -= MD_DIGEST_LENGTH/2 */
475 j = (num >= MD_DIGEST_LENGTH / 2) ? MD_DIGEST_LENGTH / 2 : num;
476 num -= j;
477 if (!MD_Init(&m))
478 goto err;
479 #ifndef GETPID_IS_MEANINGLESS
480 if (curr_pid) { /* just in the first iteration to save time */
481 if (!MD_Update(&m, (unsigned char *)&curr_pid, sizeof(curr_pid)))
482 goto err;
483 curr_pid = 0;
484 }
485 #endif
486 if (!MD_Update(&m, local_md, MD_DIGEST_LENGTH) ||
487 !MD_Update(&m, (unsigned char *)&(md_c[0]), sizeof(md_c)))
488 goto err;
489
490 #ifndef PURIFY /* purify complains */
491 /*
492 * The following line uses the supplied buffer as a small source of
493 * entropy: since this buffer is often uninitialised it may cause
494 * programs such as purify or valgrind to complain. So for those
495 * builds it is not used: the removal of such a small source of
496 * entropy has negligible impact on security.
497 */
498 if (!MD_Update(&m, buf, j))
499 goto err;
500 #endif
501
502 k = (st_idx + MD_DIGEST_LENGTH / 2) - st_num;
503 if (k > 0) {
504 if (!MD_Update(&m, &(state[st_idx]), MD_DIGEST_LENGTH / 2 - k) ||
505 !MD_Update(&m, &(state[0]), k))
506 goto err;
507 } else {
508 if (!MD_Update(&m, &(state[st_idx]), MD_DIGEST_LENGTH / 2))
509 goto err;
510 }
511 if (!MD_Final(&m, local_md))
512 goto err;
513
514 for (i = 0; i < MD_DIGEST_LENGTH / 2; i++) {
515 /* may compete with other threads */
516 state[st_idx++] ^= local_md[i];
517 if (st_idx >= st_num)
518 st_idx = 0;
519 if (i < j)
520 *(buf++) = local_md[i + MD_DIGEST_LENGTH / 2];
521 }
522 }
523
524 if (!MD_Init(&m) ||
525 !MD_Update(&m, (unsigned char *)&(md_c[0]), sizeof(md_c)) ||
526 !MD_Update(&m, local_md, MD_DIGEST_LENGTH))
527 goto err;
528 if (lock)
529 CRYPTO_w_lock(CRYPTO_LOCK_RAND);
530 if (!MD_Update(&m, md, MD_DIGEST_LENGTH) ||
531 !MD_Final(&m, md)) {
532 if (lock)
533 CRYPTO_w_unlock(CRYPTO_LOCK_RAND);
534 goto err;
535 }
536 if (lock)
537 CRYPTO_w_unlock(CRYPTO_LOCK_RAND);
538
539 EVP_MD_CTX_cleanup(&m);
540 if (initialized)
541 return (1);
542 else if (pseudo)
543 return 0;
544 else {
545 RANDerr(RAND_F_SSLEAY_RAND_BYTES, RAND_R_PRNG_NOT_SEEDED);
546 ERR_add_error_data(1, "You need to read the OpenSSL FAQ, "
547 "http://www.openssl.org/support/faq.html");
548 return (0);
549 }
550
551 err:
552 EVP_MD_CTX_cleanup(&m);
553 return (0);
554 }
555
556 /*
557 * Returns ssleay_rand_bytes(), enforcing a reseeding from the
558 * system entropy sources using RAND_poll() before generating
559 `* the random bytes.
560 */
561
562 int ssleay_rand_bytes_from_system(unsigned char *buf, int num)
563 {
564 initialized = 0;
565 return ssleay_rand_bytes(buf, num, 0, 0);
566 }
567
568 static int ssleay_rand_nopseudo_bytes(unsigned char *buf, int num)
569 {
570 return ssleay_rand_bytes(buf, num, 0, 1);
571 }
572
573 /*
574 * pseudo-random bytes that are guaranteed to be unique but not unpredictable
575 */
576 static int ssleay_rand_pseudo_bytes(unsigned char *buf, int num)
577 {
578 return ssleay_rand_bytes(buf, num, 1, 1);
579 }
580
581 static int ssleay_rand_status(void)
582 {
583 CRYPTO_THREADID cur;
584 int ret;
585 int do_not_lock;
586
587 CRYPTO_THREADID_current(&cur);
588 /*
589 * check if we already have the lock (could happen if a RAND_poll()
590 * implementation calls RAND_status())
591 */
592 if (crypto_lock_rand) {
593 CRYPTO_r_lock(CRYPTO_LOCK_RAND2);
594 do_not_lock = !CRYPTO_THREADID_cmp(&locking_threadid, &cur);
595 CRYPTO_r_unlock(CRYPTO_LOCK_RAND2);
596 } else
597 do_not_lock = 0;
598
599 if (!do_not_lock) {
600 CRYPTO_w_lock(CRYPTO_LOCK_RAND);
601
602 /*
603 * prevent ssleay_rand_bytes() from trying to obtain the lock again
604 */
605 CRYPTO_w_lock(CRYPTO_LOCK_RAND2);
606 CRYPTO_THREADID_cpy(&locking_threadid, &cur);
607 CRYPTO_w_unlock(CRYPTO_LOCK_RAND2);
608 crypto_lock_rand = 1;
609 }
610
611 if (!initialized) {
612 RAND_poll();
613 initialized = (entropy >= ENTROPY_NEEDED);
614 }
615
616 ret = initialized;
617
618 if (!do_not_lock) {
619 /* before unlocking, we must clear 'crypto_lock_rand' */
620 crypto_lock_rand = 0;
621
622 CRYPTO_w_unlock(CRYPTO_LOCK_RAND);
623 }
624
625 return ret;
626 }