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diff --git a/src/lib/libcrypto/rsa/rsa_eay.c b/src/lib/libcrypto/rsa/rsa_eay.c
deleted file mode 100644
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@@ -1,902 +0,0 @@
1/* $OpenBSD: rsa_eay.c,v 1.65 2023/08/09 12:09:06 tb Exp $ */
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) 1998-2006 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#include <stdio.h>
113#include <string.h>
114
115#include <openssl/opensslconf.h>
116
117#include <openssl/bn.h>
118#include <openssl/err.h>
119#include <openssl/rsa.h>
120
121#include "bn_local.h"
122#include "rsa_local.h"
123
124static int
125rsa_public_encrypt(int flen, const unsigned char *from, unsigned char *to,
126 RSA *rsa, int padding)
127{
128 BIGNUM *f, *ret;
129 int i, j, k, num = 0, r = -1;
130 unsigned char *buf = NULL;
131 BN_CTX *ctx = NULL;
132
133 if (BN_num_bits(rsa->n) > OPENSSL_RSA_MAX_MODULUS_BITS) {
134 RSAerror(RSA_R_MODULUS_TOO_LARGE);
135 return -1;
136 }
137
138 if (BN_ucmp(rsa->n, rsa->e) <= 0) {
139 RSAerror(RSA_R_BAD_E_VALUE);
140 return -1;
141 }
142
143 /* for large moduli, enforce exponent limit */
144 if (BN_num_bits(rsa->n) > OPENSSL_RSA_SMALL_MODULUS_BITS) {
145 if (BN_num_bits(rsa->e) > OPENSSL_RSA_MAX_PUBEXP_BITS) {
146 RSAerror(RSA_R_BAD_E_VALUE);
147 return -1;
148 }
149 }
150
151 if ((ctx = BN_CTX_new()) == NULL)
152 goto err;
153
154 BN_CTX_start(ctx);
155 f = BN_CTX_get(ctx);
156 ret = BN_CTX_get(ctx);
157 num = BN_num_bytes(rsa->n);
158 buf = malloc(num);
159
160 if (f == NULL || ret == NULL || buf == NULL) {
161 RSAerror(ERR_R_MALLOC_FAILURE);
162 goto err;
163 }
164
165 switch (padding) {
166 case RSA_PKCS1_PADDING:
167 i = RSA_padding_add_PKCS1_type_2(buf, num, from, flen);
168 break;
169#ifndef OPENSSL_NO_SHA
170 case RSA_PKCS1_OAEP_PADDING:
171 i = RSA_padding_add_PKCS1_OAEP(buf, num, from, flen, NULL, 0);
172 break;
173#endif
174 case RSA_NO_PADDING:
175 i = RSA_padding_add_none(buf, num, from, flen);
176 break;
177 default:
178 RSAerror(RSA_R_UNKNOWN_PADDING_TYPE);
179 goto err;
180 }
181 if (i <= 0)
182 goto err;
183
184 if (BN_bin2bn(buf, num, f) == NULL)
185 goto err;
186
187 if (BN_ucmp(f, rsa->n) >= 0) {
188 /* usually the padding functions would catch this */
189 RSAerror(RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
190 goto err;
191 }
192
193 if (rsa->flags & RSA_FLAG_CACHE_PUBLIC) {
194 if (!BN_MONT_CTX_set_locked(&rsa->_method_mod_n,
195 CRYPTO_LOCK_RSA, rsa->n, ctx))
196 goto err;
197 }
198
199 if (!rsa->meth->bn_mod_exp(ret, f, rsa->e, rsa->n, ctx,
200 rsa->_method_mod_n))
201 goto err;
202
203 /* put in leading 0 bytes if the number is less than the
204 * length of the modulus */
205 j = BN_num_bytes(ret);
206 i = BN_bn2bin(ret, &(to[num - j]));
207 for (k = 0; k < num - i; k++)
208 to[k] = 0;
209
210 r = num;
211err:
212 if (ctx != NULL) {
213 BN_CTX_end(ctx);
214 BN_CTX_free(ctx);
215 }
216 freezero(buf, num);
217 return r;
218}
219
220static BN_BLINDING *
221rsa_get_blinding(RSA *rsa, int *local, BN_CTX *ctx)
222{
223 BN_BLINDING *ret;
224 int got_write_lock = 0;
225
226 CRYPTO_r_lock(CRYPTO_LOCK_RSA);
227
228 if (rsa->blinding == NULL) {
229 CRYPTO_r_unlock(CRYPTO_LOCK_RSA);
230 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
231 got_write_lock = 1;
232
233 if (rsa->blinding == NULL)
234 rsa->blinding = RSA_setup_blinding(rsa, ctx);
235 }
236
237 if ((ret = rsa->blinding) == NULL)
238 goto err;
239
240 /*
241 * We need a shared blinding. Accesses require locks and a copy of the
242 * blinding factor needs to be retained on use.
243 */
244 if ((*local = BN_BLINDING_is_local(ret)) == 0) {
245 if (rsa->mt_blinding == NULL) {
246 if (!got_write_lock) {
247 CRYPTO_r_unlock(CRYPTO_LOCK_RSA);
248 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
249 got_write_lock = 1;
250 }
251
252 if (rsa->mt_blinding == NULL)
253 rsa->mt_blinding = RSA_setup_blinding(rsa, ctx);
254 }
255 ret = rsa->mt_blinding;
256 }
257
258 err:
259 if (got_write_lock)
260 CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
261 else
262 CRYPTO_r_unlock(CRYPTO_LOCK_RSA);
263
264 return ret;
265}
266
267static int
268rsa_blinding_convert(BN_BLINDING *b, BIGNUM *f, BIGNUM *unblind, BN_CTX *ctx)
269{
270 if (unblind == NULL)
271 /*
272 * Local blinding: store the unblinding factor
273 * in BN_BLINDING.
274 */
275 return BN_BLINDING_convert(f, NULL, b, ctx);
276 else {
277 /*
278 * Shared blinding: store the unblinding factor
279 * outside BN_BLINDING.
280 */
281 int ret;
282 CRYPTO_w_lock(CRYPTO_LOCK_RSA_BLINDING);
283 ret = BN_BLINDING_convert(f, unblind, b, ctx);
284 CRYPTO_w_unlock(CRYPTO_LOCK_RSA_BLINDING);
285 return ret;
286 }
287}
288
289static int
290rsa_blinding_invert(BN_BLINDING *b, BIGNUM *f, BIGNUM *unblind, BN_CTX *ctx)
291{
292 /*
293 * For local blinding, unblind is set to NULL, and BN_BLINDING_invert()
294 * will use the unblinding factor stored in BN_BLINDING.
295 * If BN_BLINDING is shared between threads, unblind must be non-null:
296 * BN_BLINDING_invert() will then use the local unblinding factor,
297 * and will only read the modulus from BN_BLINDING.
298 * In both cases it's safe to access the blinding without a lock.
299 */
300 return BN_BLINDING_invert(f, unblind, b, ctx);
301}
302
303/* signing */
304static int
305rsa_private_encrypt(int flen, const unsigned char *from, unsigned char *to,
306 RSA *rsa, int padding)
307{
308 BIGNUM *f, *ret, *res;
309 int i, j, k, num = 0, r = -1;
310 unsigned char *buf = NULL;
311 BN_CTX *ctx = NULL;
312 int local_blinding = 0;
313 /*
314 * Used only if the blinding structure is shared. A non-NULL unblind
315 * instructs rsa_blinding_convert() and rsa_blinding_invert() to store
316 * the unblinding factor outside the blinding structure.
317 */
318 BIGNUM *unblind = NULL;
319 BN_BLINDING *blinding = NULL;
320
321 if ((ctx = BN_CTX_new()) == NULL)
322 goto err;
323
324 BN_CTX_start(ctx);
325 f = BN_CTX_get(ctx);
326 ret = BN_CTX_get(ctx);
327 num = BN_num_bytes(rsa->n);
328 buf = malloc(num);
329
330 if (f == NULL || ret == NULL || buf == NULL) {
331 RSAerror(ERR_R_MALLOC_FAILURE);
332 goto err;
333 }
334
335 switch (padding) {
336 case RSA_PKCS1_PADDING:
337 i = RSA_padding_add_PKCS1_type_1(buf, num, from, flen);
338 break;
339 case RSA_X931_PADDING:
340 i = RSA_padding_add_X931(buf, num, from, flen);
341 break;
342 case RSA_NO_PADDING:
343 i = RSA_padding_add_none(buf, num, from, flen);
344 break;
345 default:
346 RSAerror(RSA_R_UNKNOWN_PADDING_TYPE);
347 goto err;
348 }
349 if (i <= 0)
350 goto err;
351
352 if (BN_bin2bn(buf, num, f) == NULL)
353 goto err;
354
355 if (BN_ucmp(f, rsa->n) >= 0) {
356 /* usually the padding functions would catch this */
357 RSAerror(RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
358 goto err;
359 }
360
361 if (rsa->flags & RSA_FLAG_CACHE_PUBLIC) {
362 if (!BN_MONT_CTX_set_locked(&rsa->_method_mod_n,
363 CRYPTO_LOCK_RSA, rsa->n, ctx))
364 goto err;
365 }
366
367 if (!(rsa->flags & RSA_FLAG_NO_BLINDING)) {
368 blinding = rsa_get_blinding(rsa, &local_blinding, ctx);
369 if (blinding == NULL) {
370 RSAerror(ERR_R_INTERNAL_ERROR);
371 goto err;
372 }
373 }
374
375 if (blinding != NULL) {
376 if (!local_blinding && ((unblind = BN_CTX_get(ctx)) == NULL)) {
377 RSAerror(ERR_R_MALLOC_FAILURE);
378 goto err;
379 }
380 if (!rsa_blinding_convert(blinding, f, unblind, ctx))
381 goto err;
382 }
383
384 if ((rsa->flags & RSA_FLAG_EXT_PKEY) ||
385 (rsa->p != NULL && rsa->q != NULL && rsa->dmp1 != NULL &&
386 rsa->dmq1 != NULL && rsa->iqmp != NULL)) {
387 if (!rsa->meth->rsa_mod_exp(ret, f, rsa, ctx))
388 goto err;
389 } else {
390 BIGNUM d;
391
392 BN_init(&d);
393 BN_with_flags(&d, rsa->d, BN_FLG_CONSTTIME);
394
395 if (!rsa->meth->bn_mod_exp(ret, f, &d, rsa->n, ctx,
396 rsa->_method_mod_n)) {
397 goto err;
398 }
399 }
400
401 if (blinding)
402 if (!rsa_blinding_invert(blinding, ret, unblind, ctx))
403 goto err;
404
405 if (padding == RSA_X931_PADDING) {
406 if (!BN_sub(f, rsa->n, ret))
407 goto err;
408 if (BN_cmp(ret, f) > 0)
409 res = f;
410 else
411 res = ret;
412 } else
413 res = ret;
414
415 /* put in leading 0 bytes if the number is less than the
416 * length of the modulus */
417 j = BN_num_bytes(res);
418 i = BN_bn2bin(res, &(to[num - j]));
419 for (k = 0; k < num - i; k++)
420 to[k] = 0;
421
422 r = num;
423err:
424 if (ctx != NULL) {
425 BN_CTX_end(ctx);
426 BN_CTX_free(ctx);
427 }
428 freezero(buf, num);
429 return r;
430}
431
432static int
433rsa_private_decrypt(int flen, const unsigned char *from, unsigned char *to,
434 RSA *rsa, int padding)
435{
436 BIGNUM *f, *ret;
437 int j, num = 0, r = -1;
438 unsigned char *p;
439 unsigned char *buf = NULL;
440 BN_CTX *ctx = NULL;
441 int local_blinding = 0;
442 /*
443 * Used only if the blinding structure is shared. A non-NULL unblind
444 * instructs rsa_blinding_convert() and rsa_blinding_invert() to store
445 * the unblinding factor outside the blinding structure.
446 */
447 BIGNUM *unblind = NULL;
448 BN_BLINDING *blinding = NULL;
449
450 if ((ctx = BN_CTX_new()) == NULL)
451 goto err;
452
453 BN_CTX_start(ctx);
454 f = BN_CTX_get(ctx);
455 ret = BN_CTX_get(ctx);
456 num = BN_num_bytes(rsa->n);
457 buf = malloc(num);
458
459 if (!f || !ret || !buf) {
460 RSAerror(ERR_R_MALLOC_FAILURE);
461 goto err;
462 }
463
464 /* This check was for equality but PGP does evil things
465 * and chops off the top '0' bytes */
466 if (flen > num) {
467 RSAerror(RSA_R_DATA_GREATER_THAN_MOD_LEN);
468 goto err;
469 }
470
471 /* make data into a big number */
472 if (BN_bin2bn(from, (int)flen, f) == NULL)
473 goto err;
474
475 if (BN_ucmp(f, rsa->n) >= 0) {
476 RSAerror(RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
477 goto err;
478 }
479
480 if (rsa->flags & RSA_FLAG_CACHE_PUBLIC) {
481 if (!BN_MONT_CTX_set_locked(&rsa->_method_mod_n,
482 CRYPTO_LOCK_RSA, rsa->n, ctx))
483 goto err;
484 }
485
486 if (!(rsa->flags & RSA_FLAG_NO_BLINDING)) {
487 blinding = rsa_get_blinding(rsa, &local_blinding, ctx);
488 if (blinding == NULL) {
489 RSAerror(ERR_R_INTERNAL_ERROR);
490 goto err;
491 }
492 }
493
494 if (blinding != NULL) {
495 if (!local_blinding && ((unblind = BN_CTX_get(ctx)) == NULL)) {
496 RSAerror(ERR_R_MALLOC_FAILURE);
497 goto err;
498 }
499 if (!rsa_blinding_convert(blinding, f, unblind, ctx))
500 goto err;
501 }
502
503 /* do the decrypt */
504 if ((rsa->flags & RSA_FLAG_EXT_PKEY) ||
505 (rsa->p != NULL && rsa->q != NULL && rsa->dmp1 != NULL &&
506 rsa->dmq1 != NULL && rsa->iqmp != NULL)) {
507 if (!rsa->meth->rsa_mod_exp(ret, f, rsa, ctx))
508 goto err;
509 } else {
510 BIGNUM d;
511
512 BN_init(&d);
513 BN_with_flags(&d, rsa->d, BN_FLG_CONSTTIME);
514
515 if (!rsa->meth->bn_mod_exp(ret, f, &d, rsa->n, ctx,
516 rsa->_method_mod_n)) {
517 goto err;
518 }
519 }
520
521 if (blinding)
522 if (!rsa_blinding_invert(blinding, ret, unblind, ctx))
523 goto err;
524
525 p = buf;
526 j = BN_bn2bin(ret, p); /* j is only used with no-padding mode */
527
528 switch (padding) {
529 case RSA_PKCS1_PADDING:
530 r = RSA_padding_check_PKCS1_type_2(to, num, buf, j, num);
531 break;
532#ifndef OPENSSL_NO_SHA
533 case RSA_PKCS1_OAEP_PADDING:
534 r = RSA_padding_check_PKCS1_OAEP(to, num, buf, j, num, NULL, 0);
535 break;
536#endif
537 case RSA_NO_PADDING:
538 r = RSA_padding_check_none(to, num, buf, j, num);
539 break;
540 default:
541 RSAerror(RSA_R_UNKNOWN_PADDING_TYPE);
542 goto err;
543 }
544 if (r < 0)
545 RSAerror(RSA_R_PADDING_CHECK_FAILED);
546
547err:
548 if (ctx != NULL) {
549 BN_CTX_end(ctx);
550 BN_CTX_free(ctx);
551 }
552 freezero(buf, num);
553 return r;
554}
555
556/* signature verification */
557static int
558rsa_public_decrypt(int flen, const unsigned char *from, unsigned char *to,
559 RSA *rsa, int padding)
560{
561 BIGNUM *f, *ret;
562 int i, num = 0, r = -1;
563 unsigned char *p;
564 unsigned char *buf = NULL;
565 BN_CTX *ctx = NULL;
566
567 if (BN_num_bits(rsa->n) > OPENSSL_RSA_MAX_MODULUS_BITS) {
568 RSAerror(RSA_R_MODULUS_TOO_LARGE);
569 return -1;
570 }
571
572 if (BN_ucmp(rsa->n, rsa->e) <= 0) {
573 RSAerror(RSA_R_BAD_E_VALUE);
574 return -1;
575 }
576
577 /* for large moduli, enforce exponent limit */
578 if (BN_num_bits(rsa->n) > OPENSSL_RSA_SMALL_MODULUS_BITS) {
579 if (BN_num_bits(rsa->e) > OPENSSL_RSA_MAX_PUBEXP_BITS) {
580 RSAerror(RSA_R_BAD_E_VALUE);
581 return -1;
582 }
583 }
584
585 if ((ctx = BN_CTX_new()) == NULL)
586 goto err;
587
588 BN_CTX_start(ctx);
589 f = BN_CTX_get(ctx);
590 ret = BN_CTX_get(ctx);
591 num = BN_num_bytes(rsa->n);
592 buf = malloc(num);
593
594 if (!f || !ret || !buf) {
595 RSAerror(ERR_R_MALLOC_FAILURE);
596 goto err;
597 }
598
599 /* This check was for equality but PGP does evil things
600 * and chops off the top '0' bytes */
601 if (flen > num) {
602 RSAerror(RSA_R_DATA_GREATER_THAN_MOD_LEN);
603 goto err;
604 }
605
606 if (BN_bin2bn(from, flen, f) == NULL)
607 goto err;
608
609 if (BN_ucmp(f, rsa->n) >= 0) {
610 RSAerror(RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
611 goto err;
612 }
613
614 if (rsa->flags & RSA_FLAG_CACHE_PUBLIC) {
615 if (!BN_MONT_CTX_set_locked(&rsa->_method_mod_n,
616 CRYPTO_LOCK_RSA, rsa->n, ctx))
617 goto err;
618 }
619
620 if (!rsa->meth->bn_mod_exp(ret, f, rsa->e, rsa->n, ctx,
621 rsa->_method_mod_n))
622 goto err;
623
624 if (padding == RSA_X931_PADDING && (ret->d[0] & 0xf) != 12)
625 if (!BN_sub(ret, rsa->n, ret))
626 goto err;
627
628 p = buf;
629 i = BN_bn2bin(ret, p);
630
631 switch (padding) {
632 case RSA_PKCS1_PADDING:
633 r = RSA_padding_check_PKCS1_type_1(to, num, buf, i, num);
634 break;
635 case RSA_X931_PADDING:
636 r = RSA_padding_check_X931(to, num, buf, i, num);
637 break;
638 case RSA_NO_PADDING:
639 r = RSA_padding_check_none(to, num, buf, i, num);
640 break;
641 default:
642 RSAerror(RSA_R_UNKNOWN_PADDING_TYPE);
643 goto err;
644 }
645 if (r < 0)
646 RSAerror(RSA_R_PADDING_CHECK_FAILED);
647
648err:
649 if (ctx != NULL) {
650 BN_CTX_end(ctx);
651 BN_CTX_free(ctx);
652 }
653 freezero(buf, num);
654 return r;
655}
656
657static int
658rsa_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa, BN_CTX *ctx)
659{
660 BIGNUM *r1, *m1, *vrfy;
661 BIGNUM dmp1, dmq1, c, pr1;
662 int ret = 0;
663
664 BN_CTX_start(ctx);
665 r1 = BN_CTX_get(ctx);
666 m1 = BN_CTX_get(ctx);
667 vrfy = BN_CTX_get(ctx);
668 if (r1 == NULL || m1 == NULL || vrfy == NULL) {
669 RSAerror(ERR_R_MALLOC_FAILURE);
670 goto err;
671 }
672
673 {
674 BIGNUM p, q;
675
676 /*
677 * Make sure BN_mod_inverse in Montgomery initialization uses the
678 * BN_FLG_CONSTTIME flag
679 */
680 BN_init(&p);
681 BN_init(&q);
682 BN_with_flags(&p, rsa->p, BN_FLG_CONSTTIME);
683 BN_with_flags(&q, rsa->q, BN_FLG_CONSTTIME);
684
685 if (rsa->flags & RSA_FLAG_CACHE_PRIVATE) {
686 if (!BN_MONT_CTX_set_locked(&rsa->_method_mod_p,
687 CRYPTO_LOCK_RSA, &p, ctx) ||
688 !BN_MONT_CTX_set_locked(&rsa->_method_mod_q,
689 CRYPTO_LOCK_RSA, &q, ctx)) {
690 goto err;
691 }
692 }
693 }
694
695 if (rsa->flags & RSA_FLAG_CACHE_PUBLIC) {
696 if (!BN_MONT_CTX_set_locked(&rsa->_method_mod_n,
697 CRYPTO_LOCK_RSA, rsa->n, ctx))
698 goto err;
699 }
700
701 /* compute I mod q */
702 BN_init(&c);
703 BN_with_flags(&c, I, BN_FLG_CONSTTIME);
704
705 if (!BN_mod_ct(r1, &c, rsa->q, ctx))
706 goto err;
707
708 /* compute r1^dmq1 mod q */
709 BN_init(&dmq1);
710 BN_with_flags(&dmq1, rsa->dmq1, BN_FLG_CONSTTIME);
711
712 if (!rsa->meth->bn_mod_exp(m1, r1, &dmq1, rsa->q, ctx,
713 rsa->_method_mod_q))
714 goto err;
715
716 /* compute I mod p */
717 BN_init(&c);
718 BN_with_flags(&c, I, BN_FLG_CONSTTIME);
719
720 if (!BN_mod_ct(r1, &c, rsa->p, ctx))
721 goto err;
722
723 /* compute r1^dmp1 mod p */
724 BN_init(&dmp1);
725 BN_with_flags(&dmp1, rsa->dmp1, BN_FLG_CONSTTIME);
726
727 if (!rsa->meth->bn_mod_exp(r0, r1, &dmp1, rsa->p, ctx,
728 rsa->_method_mod_p))
729 goto err;
730
731 if (!BN_sub(r0, r0, m1))
732 goto err;
733
734 /*
735 * This will help stop the size of r0 increasing, which does
736 * affect the multiply if it optimised for a power of 2 size
737 */
738 if (BN_is_negative(r0))
739 if (!BN_add(r0, r0, rsa->p))
740 goto err;
741
742 if (!BN_mul(r1, r0, rsa->iqmp, ctx))
743 goto err;
744
745 /* Turn BN_FLG_CONSTTIME flag on before division operation */
746 BN_init(&pr1);
747 BN_with_flags(&pr1, r1, BN_FLG_CONSTTIME);
748
749 if (!BN_mod_ct(r0, &pr1, rsa->p, ctx))
750 goto err;
751
752 /*
753 * If p < q it is occasionally possible for the correction of
754 * adding 'p' if r0 is negative above to leave the result still
755 * negative. This can break the private key operations: the following
756 * second correction should *always* correct this rare occurrence.
757 * This will *never* happen with OpenSSL generated keys because
758 * they ensure p > q [steve]
759 */
760 if (BN_is_negative(r0))
761 if (!BN_add(r0, r0, rsa->p))
762 goto err;
763 if (!BN_mul(r1, r0, rsa->q, ctx))
764 goto err;
765 if (!BN_add(r0, r1, m1))
766 goto err;
767
768 if (rsa->e && rsa->n) {
769 if (!rsa->meth->bn_mod_exp(vrfy, r0, rsa->e, rsa->n, ctx,
770 rsa->_method_mod_n))
771 goto err;
772 /*
773 * If 'I' was greater than (or equal to) rsa->n, the operation
774 * will be equivalent to using 'I mod n'. However, the result of
775 * the verify will *always* be less than 'n' so we don't check
776 * for absolute equality, just congruency.
777 */
778 if (!BN_sub(vrfy, vrfy, I))
779 goto err;
780 if (!BN_mod_ct(vrfy, vrfy, rsa->n, ctx))
781 goto err;
782 if (BN_is_negative(vrfy))
783 if (!BN_add(vrfy, vrfy, rsa->n))
784 goto err;
785 if (!BN_is_zero(vrfy)) {
786 /*
787 * 'I' and 'vrfy' aren't congruent mod n. Don't leak
788 * miscalculated CRT output, just do a raw (slower)
789 * mod_exp and return that instead.
790 */
791 BIGNUM d;
792
793 BN_init(&d);
794 BN_with_flags(&d, rsa->d, BN_FLG_CONSTTIME);
795
796 if (!rsa->meth->bn_mod_exp(r0, I, &d, rsa->n, ctx,
797 rsa->_method_mod_n)) {
798 goto err;
799 }
800 }
801 }
802 ret = 1;
803err:
804 BN_CTX_end(ctx);
805 return ret;
806}
807
808static int
809rsa_init(RSA *rsa)
810{
811 rsa->flags |= RSA_FLAG_CACHE_PUBLIC | RSA_FLAG_CACHE_PRIVATE;
812 return 1;
813}
814
815static int
816rsa_finish(RSA *rsa)
817{
818 BN_MONT_CTX_free(rsa->_method_mod_n);
819 BN_MONT_CTX_free(rsa->_method_mod_p);
820 BN_MONT_CTX_free(rsa->_method_mod_q);
821
822 return 1;
823}
824
825static const RSA_METHOD rsa_pkcs1_meth = {
826 .name = "OpenSSL PKCS#1 RSA",
827 .rsa_pub_enc = rsa_public_encrypt,
828 .rsa_pub_dec = rsa_public_decrypt, /* signature verification */
829 .rsa_priv_enc = rsa_private_encrypt, /* signing */
830 .rsa_priv_dec = rsa_private_decrypt,
831 .rsa_mod_exp = rsa_mod_exp,
832 .bn_mod_exp = BN_mod_exp_mont_ct, /* XXX probably we should not use Montgomery if e == 3 */
833 .init = rsa_init,
834 .finish = rsa_finish,
835};
836
837const RSA_METHOD *
838RSA_PKCS1_OpenSSL(void)
839{
840 return &rsa_pkcs1_meth;
841}
842LCRYPTO_ALIAS(RSA_PKCS1_OpenSSL);
843
844const RSA_METHOD *
845RSA_PKCS1_SSLeay(void)
846{
847 return RSA_PKCS1_OpenSSL();
848}
849LCRYPTO_ALIAS(RSA_PKCS1_SSLeay);
850
851int
852RSA_bits(const RSA *r)
853{
854 return BN_num_bits(r->n);
855}
856LCRYPTO_ALIAS(RSA_bits);
857
858int
859RSA_size(const RSA *r)
860{
861 return BN_num_bytes(r->n);
862}
863LCRYPTO_ALIAS(RSA_size);
864
865int
866RSA_public_encrypt(int flen, const unsigned char *from, unsigned char *to,
867 RSA *rsa, int padding)
868{
869 return rsa->meth->rsa_pub_enc(flen, from, to, rsa, padding);
870}
871LCRYPTO_ALIAS(RSA_public_encrypt);
872
873int
874RSA_private_encrypt(int flen, const unsigned char *from, unsigned char *to,
875 RSA *rsa, int padding)
876{
877 return rsa->meth->rsa_priv_enc(flen, from, to, rsa, padding);
878}
879LCRYPTO_ALIAS(RSA_private_encrypt);
880
881int
882RSA_private_decrypt(int flen, const unsigned char *from, unsigned char *to,
883 RSA *rsa, int padding)
884{
885 return rsa->meth->rsa_priv_dec(flen, from, to, rsa, padding);
886}
887LCRYPTO_ALIAS(RSA_private_decrypt);
888
889int
890RSA_public_decrypt(int flen, const unsigned char *from, unsigned char *to,
891 RSA *rsa, int padding)
892{
893 return rsa->meth->rsa_pub_dec(flen, from, to, rsa, padding);
894}
895LCRYPTO_ALIAS(RSA_public_decrypt);
896
897int
898RSA_flags(const RSA *r)
899{
900 return r == NULL ? 0 : r->meth->flags;
901}
902LCRYPTO_ALIAS(RSA_flags);
generated by cgit v1.2.3-55-g6feb (git 2.39.1) at 2025-12-23 15:11:07 +0000