1 /* crypto/rsa/rsa_eay.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
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.
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).
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.
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
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)"
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
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.]
58 /* ====================================================================
59 * Copyright (c) 1998-2006 The OpenSSL Project. All rights reserved.
61 * Redistribution and use in source and binary forms, with or without
62 * modification, are permitted provided that the following conditions
65 * 1. Redistributions of source code must retain the above copyright
66 * notice, this list of conditions and the following disclaimer.
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
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/)"
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.
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.
87 * 6. Redistributions of any form whatsoever must retain the following
89 * "This product includes software developed by the OpenSSL Project
90 * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
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 * ====================================================================
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).
113 #include <openssl/bn.h>
114 #include <openssl/rsa.h>
115 #include <openssl/rand.h>
116 #include <openssl/err.h>
117 #include <openssl/fips.h>
119 #if !defined(RSA_NULL) && defined(OPENSSL_FIPS)
121 static int RSA_eay_public_encrypt(int flen, const unsigned char *from,
122 unsigned char *to, RSA *rsa, int padding);
123 static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
124 unsigned char *to, RSA *rsa, int padding);
125 static int RSA_eay_public_decrypt(int flen, const unsigned char *from,
126 unsigned char *to, RSA *rsa, int padding);
127 static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
128 unsigned char *to, RSA *rsa, int padding);
129 static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *i, RSA *rsa,
131 static int RSA_eay_init(RSA *rsa);
132 static int RSA_eay_finish(RSA *rsa);
133 static RSA_METHOD rsa_pkcs1_eay_meth = {
134 "Eric Young's PKCS#1 RSA",
135 RSA_eay_public_encrypt,
136 RSA_eay_public_decrypt, /* signature verification */
137 RSA_eay_private_encrypt, /* signing */
138 RSA_eay_private_decrypt,
140 BN_mod_exp_mont, /* XXX probably we should not use Montgomery
144 RSA_FLAG_FIPS_METHOD, /* flags */
148 NULL /* rsa_keygen */
151 const RSA_METHOD *RSA_PKCS1_SSLeay(void)
153 return (&rsa_pkcs1_eay_meth);
157 * Usage example; MONT_HELPER(rsa, bn_ctx, p, rsa->flags &
158 * RSA_FLAG_CACHE_PRIVATE, goto err);
160 # define MONT_HELPER(rsa, ctx, m, pre_cond, err_instr) \
161 if ((pre_cond) && ((rsa)->_method_mod_##m == NULL) && \
162 !BN_MONT_CTX_set_locked(&((rsa)->_method_mod_##m), \
167 static int RSA_eay_public_encrypt(int flen, const unsigned char *from,
168 unsigned char *to, RSA *rsa, int padding)
171 int i, j, k, num = 0, r = -1;
172 unsigned char *buf = NULL;
175 if (FIPS_selftest_failed()) {
176 FIPSerr(FIPS_F_RSA_EAY_PUBLIC_ENCRYPT, FIPS_R_FIPS_SELFTEST_FAILED);
181 && (BN_num_bits(rsa->n) < OPENSSL_RSA_FIPS_MIN_MODULUS_BITS)) {
182 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT, RSA_R_KEY_SIZE_TOO_SMALL);
186 if (BN_num_bits(rsa->n) > OPENSSL_RSA_MAX_MODULUS_BITS) {
187 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT, RSA_R_MODULUS_TOO_LARGE);
191 if (BN_ucmp(rsa->n, rsa->e) <= 0) {
192 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT, RSA_R_BAD_E_VALUE);
196 /* for large moduli, enforce exponent limit */
197 if (BN_num_bits(rsa->n) > OPENSSL_RSA_SMALL_MODULUS_BITS) {
198 if (BN_num_bits(rsa->e) > OPENSSL_RSA_MAX_PUBEXP_BITS) {
199 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT, RSA_R_BAD_E_VALUE);
204 if ((ctx = BN_CTX_new()) == NULL)
208 ret = BN_CTX_get(ctx);
209 num = BN_num_bytes(rsa->n);
210 buf = OPENSSL_malloc(num);
211 if (!f || !ret || !buf) {
212 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT, ERR_R_MALLOC_FAILURE);
217 case RSA_PKCS1_PADDING:
218 i = RSA_padding_add_PKCS1_type_2(buf, num, from, flen);
220 # ifndef OPENSSL_NO_SHA
221 case RSA_PKCS1_OAEP_PADDING:
222 i = RSA_padding_add_PKCS1_OAEP(buf, num, from, flen, NULL, 0);
225 case RSA_SSLV23_PADDING:
226 i = RSA_padding_add_SSLv23(buf, num, from, flen);
229 i = RSA_padding_add_none(buf, num, from, flen);
232 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT, RSA_R_UNKNOWN_PADDING_TYPE);
238 if (BN_bin2bn(buf, num, f) == NULL)
241 if (BN_ucmp(f, rsa->n) >= 0) {
242 /* usually the padding functions would catch this */
243 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,
244 RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
248 MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
250 if (!rsa->meth->bn_mod_exp(ret, f, rsa->e, rsa->n, ctx,
255 * put in leading 0 bytes if the number is less than the length of the
258 j = BN_num_bytes(ret);
259 i = BN_bn2bin(ret, &(to[num - j]));
260 for (k = 0; k < (num - i); k++)
270 OPENSSL_cleanse(buf, num);
276 static BN_BLINDING *rsa_get_blinding(RSA *rsa, int *local, BN_CTX *ctx)
279 int got_write_lock = 0;
281 CRYPTO_r_lock(CRYPTO_LOCK_RSA);
283 if (rsa->blinding == NULL) {
284 CRYPTO_r_unlock(CRYPTO_LOCK_RSA);
285 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
288 if (rsa->blinding == NULL)
289 rsa->blinding = RSA_setup_blinding(rsa, ctx);
296 if (BN_BLINDING_get_thread_id(ret) == CRYPTO_thread_id()) {
297 /* rsa->blinding is ours! */
301 /* resort to rsa->mt_blinding instead */
304 * instructs rsa_blinding_convert(), rsa_blinding_invert() that the
305 * BN_BLINDING is shared, meaning that accesses require locks, and
306 * that the blinding factor must be stored outside the BN_BLINDING
310 if (rsa->mt_blinding == NULL) {
311 if (!got_write_lock) {
312 CRYPTO_r_unlock(CRYPTO_LOCK_RSA);
313 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
317 if (rsa->mt_blinding == NULL)
318 rsa->mt_blinding = RSA_setup_blinding(rsa, ctx);
320 ret = rsa->mt_blinding;
325 CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
327 CRYPTO_r_unlock(CRYPTO_LOCK_RSA);
331 static int rsa_blinding_convert(BN_BLINDING *b, int local, BIGNUM *f,
332 BIGNUM *r, BN_CTX *ctx)
335 return BN_BLINDING_convert_ex(f, NULL, b, ctx);
338 CRYPTO_r_lock(CRYPTO_LOCK_RSA_BLINDING);
339 ret = BN_BLINDING_convert_ex(f, r, b, ctx);
340 CRYPTO_r_unlock(CRYPTO_LOCK_RSA_BLINDING);
345 static int rsa_blinding_invert(BN_BLINDING *b, int local, BIGNUM *f,
346 BIGNUM *r, BN_CTX *ctx)
349 return BN_BLINDING_invert_ex(f, NULL, b, ctx);
352 CRYPTO_w_lock(CRYPTO_LOCK_RSA_BLINDING);
353 ret = BN_BLINDING_invert_ex(f, r, b, ctx);
354 CRYPTO_w_unlock(CRYPTO_LOCK_RSA_BLINDING);
360 static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
361 unsigned char *to, RSA *rsa, int padding)
363 BIGNUM *f, *ret, *br, *res;
364 int i, j, k, num = 0, r = -1;
365 unsigned char *buf = NULL;
367 int local_blinding = 0;
368 BN_BLINDING *blinding = NULL;
370 if (FIPS_selftest_failed()) {
371 FIPSerr(FIPS_F_RSA_EAY_PRIVATE_ENCRYPT, FIPS_R_FIPS_SELFTEST_FAILED);
376 && (BN_num_bits(rsa->n) < OPENSSL_RSA_FIPS_MIN_MODULUS_BITS)) {
377 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT, RSA_R_KEY_SIZE_TOO_SMALL);
381 if ((ctx = BN_CTX_new()) == NULL)
385 br = BN_CTX_get(ctx);
386 ret = BN_CTX_get(ctx);
387 num = BN_num_bytes(rsa->n);
388 buf = OPENSSL_malloc(num);
389 if (!f || !ret || !buf) {
390 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT, ERR_R_MALLOC_FAILURE);
395 case RSA_PKCS1_PADDING:
396 i = RSA_padding_add_PKCS1_type_1(buf, num, from, flen);
398 case RSA_X931_PADDING:
399 i = RSA_padding_add_X931(buf, num, from, flen);
402 i = RSA_padding_add_none(buf, num, from, flen);
404 case RSA_SSLV23_PADDING:
406 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT, RSA_R_UNKNOWN_PADDING_TYPE);
412 if (BN_bin2bn(buf, num, f) == NULL)
415 if (BN_ucmp(f, rsa->n) >= 0) {
416 /* usually the padding functions would catch this */
417 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,
418 RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
422 if (!(rsa->flags & RSA_FLAG_NO_BLINDING)) {
423 blinding = rsa_get_blinding(rsa, &local_blinding, ctx);
424 if (blinding == NULL) {
425 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT, ERR_R_INTERNAL_ERROR);
430 if (blinding != NULL)
431 if (!rsa_blinding_convert(blinding, local_blinding, f, br, ctx))
434 if ((rsa->flags & RSA_FLAG_EXT_PKEY) ||
437 (rsa->dmp1 != NULL) && (rsa->dmq1 != NULL) && (rsa->iqmp != NULL))) {
438 if (!rsa->meth->rsa_mod_exp(ret, f, rsa, ctx))
444 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) {
447 BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
451 MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC,
454 if (!rsa->meth->bn_mod_exp(ret, f, d, rsa->n, ctx,
460 if (!rsa_blinding_invert(blinding, local_blinding, ret, br, ctx))
463 if (padding == RSA_X931_PADDING) {
464 BN_sub(f, rsa->n, ret);
473 * put in leading 0 bytes if the number is less than the length of the
476 j = BN_num_bytes(res);
477 i = BN_bn2bin(res, &(to[num - j]));
478 for (k = 0; k < (num - i); k++)
488 OPENSSL_cleanse(buf, num);
494 static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
495 unsigned char *to, RSA *rsa, int padding)
497 BIGNUM *f, *ret, *br;
498 int j, num = 0, r = -1;
500 unsigned char *buf = NULL;
502 int local_blinding = 0;
503 BN_BLINDING *blinding = NULL;
505 if (FIPS_selftest_failed()) {
506 FIPSerr(FIPS_F_RSA_EAY_PRIVATE_DECRYPT, FIPS_R_FIPS_SELFTEST_FAILED);
511 && (BN_num_bits(rsa->n) < OPENSSL_RSA_FIPS_MIN_MODULUS_BITS)) {
512 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT, RSA_R_KEY_SIZE_TOO_SMALL);
516 if ((ctx = BN_CTX_new()) == NULL)
520 br = BN_CTX_get(ctx);
521 ret = BN_CTX_get(ctx);
522 num = BN_num_bytes(rsa->n);
523 buf = OPENSSL_malloc(num);
524 if (!f || !ret || !buf) {
525 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT, ERR_R_MALLOC_FAILURE);
530 * This check was for equality but PGP does evil things and chops off the
534 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,
535 RSA_R_DATA_GREATER_THAN_MOD_LEN);
539 /* make data into a big number */
540 if (BN_bin2bn(from, (int)flen, f) == NULL)
543 if (BN_ucmp(f, rsa->n) >= 0) {
544 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,
545 RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
549 if (!(rsa->flags & RSA_FLAG_NO_BLINDING)) {
550 blinding = rsa_get_blinding(rsa, &local_blinding, ctx);
551 if (blinding == NULL) {
552 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT, ERR_R_INTERNAL_ERROR);
557 if (blinding != NULL)
558 if (!rsa_blinding_convert(blinding, local_blinding, f, br, ctx))
562 if ((rsa->flags & RSA_FLAG_EXT_PKEY) ||
565 (rsa->dmp1 != NULL) && (rsa->dmq1 != NULL) && (rsa->iqmp != NULL))) {
566 if (!rsa->meth->rsa_mod_exp(ret, f, rsa, ctx))
572 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) {
574 BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
578 MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC,
581 meth->bn_mod_exp(ret, f, d, rsa->n, ctx, rsa->_method_mod_n))
586 if (!rsa_blinding_invert(blinding, local_blinding, ret, br, ctx))
590 j = BN_bn2bin(ret, p); /* j is only used with no-padding mode */
593 case RSA_PKCS1_PADDING:
594 r = RSA_padding_check_PKCS1_type_2(to, num, buf, j, num);
596 # ifndef OPENSSL_NO_SHA
597 case RSA_PKCS1_OAEP_PADDING:
598 r = RSA_padding_check_PKCS1_OAEP(to, num, buf, j, num, NULL, 0);
601 case RSA_SSLV23_PADDING:
602 r = RSA_padding_check_SSLv23(to, num, buf, j, num);
605 r = RSA_padding_check_none(to, num, buf, j, num);
608 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT, RSA_R_UNKNOWN_PADDING_TYPE);
612 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT, RSA_R_PADDING_CHECK_FAILED);
620 OPENSSL_cleanse(buf, num);
626 /* signature verification */
627 static int RSA_eay_public_decrypt(int flen, const unsigned char *from,
628 unsigned char *to, RSA *rsa, int padding)
631 int i, num = 0, r = -1;
633 unsigned char *buf = NULL;
636 if (FIPS_selftest_failed()) {
637 FIPSerr(FIPS_F_RSA_EAY_PUBLIC_DECRYPT, FIPS_R_FIPS_SELFTEST_FAILED);
642 && (BN_num_bits(rsa->n) < OPENSSL_RSA_FIPS_MIN_MODULUS_BITS)) {
643 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_KEY_SIZE_TOO_SMALL);
647 if (BN_num_bits(rsa->n) > OPENSSL_RSA_MAX_MODULUS_BITS) {
648 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_MODULUS_TOO_LARGE);
652 if (BN_ucmp(rsa->n, rsa->e) <= 0) {
653 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_BAD_E_VALUE);
657 /* for large moduli, enforce exponent limit */
658 if (BN_num_bits(rsa->n) > OPENSSL_RSA_SMALL_MODULUS_BITS) {
659 if (BN_num_bits(rsa->e) > OPENSSL_RSA_MAX_PUBEXP_BITS) {
660 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_BAD_E_VALUE);
665 if ((ctx = BN_CTX_new()) == NULL)
669 ret = BN_CTX_get(ctx);
670 num = BN_num_bytes(rsa->n);
671 buf = OPENSSL_malloc(num);
672 if (!f || !ret || !buf) {
673 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, ERR_R_MALLOC_FAILURE);
678 * This check was for equality but PGP does evil things and chops off the
682 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_DATA_GREATER_THAN_MOD_LEN);
686 if (BN_bin2bn(from, flen, f) == NULL)
689 if (BN_ucmp(f, rsa->n) >= 0) {
690 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,
691 RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
695 MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
697 if (!rsa->meth->bn_mod_exp(ret, f, rsa->e, rsa->n, ctx,
701 if ((padding == RSA_X931_PADDING) && ((ret->d[0] & 0xf) != 12))
702 BN_sub(ret, rsa->n, ret);
705 i = BN_bn2bin(ret, p);
708 case RSA_PKCS1_PADDING:
709 r = RSA_padding_check_PKCS1_type_1(to, num, buf, i, num);
711 case RSA_X931_PADDING:
712 r = RSA_padding_check_X931(to, num, buf, i, num);
715 r = RSA_padding_check_none(to, num, buf, i, num);
718 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_UNKNOWN_PADDING_TYPE);
722 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_PADDING_CHECK_FAILED);
730 OPENSSL_cleanse(buf, num);
736 static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa, BN_CTX *ctx)
738 BIGNUM *r1, *m1, *vrfy;
739 BIGNUM local_dmp1, local_dmq1, local_c, local_r1;
740 BIGNUM *dmp1, *dmq1, *c, *pr1;
745 r1 = BN_CTX_get(ctx);
746 m1 = BN_CTX_get(ctx);
747 vrfy = BN_CTX_get(ctx);
750 * Make sure mod_inverse in montgomerey intialization use correct
751 * BN_FLG_CONSTTIME flag.
753 bn_flags = rsa->p->flags;
754 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) {
755 rsa->p->flags |= BN_FLG_CONSTTIME;
757 MONT_HELPER(rsa, ctx, p, rsa->flags & RSA_FLAG_CACHE_PRIVATE, goto err);
758 /* We restore bn_flags back */
759 rsa->p->flags = bn_flags;
762 * Make sure mod_inverse in montgomerey intialization use correct
763 * BN_FLG_CONSTTIME flag.
765 bn_flags = rsa->q->flags;
766 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) {
767 rsa->q->flags |= BN_FLG_CONSTTIME;
769 MONT_HELPER(rsa, ctx, q, rsa->flags & RSA_FLAG_CACHE_PRIVATE, goto err);
770 /* We restore bn_flags back */
771 rsa->q->flags = bn_flags;
773 MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
775 /* compute I mod q */
776 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) {
778 BN_with_flags(c, I, BN_FLG_CONSTTIME);
779 if (!BN_mod(r1, c, rsa->q, ctx))
782 if (!BN_mod(r1, I, rsa->q, ctx))
786 /* compute r1^dmq1 mod q */
787 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) {
789 BN_with_flags(dmq1, rsa->dmq1, BN_FLG_CONSTTIME);
792 if (!rsa->meth->bn_mod_exp(m1, r1, dmq1, rsa->q, ctx, rsa->_method_mod_q))
795 /* compute I mod p */
796 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) {
798 BN_with_flags(c, I, BN_FLG_CONSTTIME);
799 if (!BN_mod(r1, c, rsa->p, ctx))
802 if (!BN_mod(r1, I, rsa->p, ctx))
806 /* compute r1^dmp1 mod p */
807 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) {
809 BN_with_flags(dmp1, rsa->dmp1, BN_FLG_CONSTTIME);
812 if (!rsa->meth->bn_mod_exp(r0, r1, dmp1, rsa->p, ctx, rsa->_method_mod_p))
815 if (!BN_sub(r0, r0, m1))
818 * This will help stop the size of r0 increasing, which does affect the
819 * multiply if it optimised for a power of 2 size
821 if (BN_is_negative(r0))
822 if (!BN_add(r0, r0, rsa->p))
825 if (!BN_mul(r1, r0, rsa->iqmp, ctx))
828 /* Turn BN_FLG_CONSTTIME flag on before division operation */
829 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) {
831 BN_with_flags(pr1, r1, BN_FLG_CONSTTIME);
834 if (!BN_mod(r0, pr1, rsa->p, ctx))
838 * If p < q it is occasionally possible for the correction of adding 'p'
839 * if r0 is negative above to leave the result still negative. This can
840 * break the private key operations: the following second correction
841 * should *always* correct this rare occurrence. This will *never* happen
842 * with OpenSSL generated keys because they ensure p > q [steve]
844 if (BN_is_negative(r0))
845 if (!BN_add(r0, r0, rsa->p))
847 if (!BN_mul(r1, r0, rsa->q, ctx))
849 if (!BN_add(r0, r1, m1))
852 if (rsa->e && rsa->n) {
853 if (!rsa->meth->bn_mod_exp(vrfy, r0, rsa->e, rsa->n, ctx,
857 * If 'I' was greater than (or equal to) rsa->n, the operation will
858 * be equivalent to using 'I mod n'. However, the result of the
859 * verify will *always* be less than 'n' so we don't check for
860 * absolute equality, just congruency.
862 if (!BN_sub(vrfy, vrfy, I))
864 if (!BN_mod(vrfy, vrfy, rsa->n, ctx))
866 if (BN_is_negative(vrfy))
867 if (!BN_add(vrfy, vrfy, rsa->n))
869 if (!BN_is_zero(vrfy)) {
871 * 'I' and 'vrfy' aren't congruent mod n. Don't leak
872 * miscalculated CRT output, just do a raw (slower) mod_exp and
873 * return that instead.
879 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) {
881 BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
884 if (!rsa->meth->bn_mod_exp(r0, I, d, rsa->n, ctx,
895 static int RSA_eay_init(RSA *rsa)
897 FIPS_selftest_check();
898 rsa->flags |= RSA_FLAG_CACHE_PUBLIC | RSA_FLAG_CACHE_PRIVATE;
902 static int RSA_eay_finish(RSA *rsa)
904 if (rsa->_method_mod_n != NULL)
905 BN_MONT_CTX_free(rsa->_method_mod_n);
906 if (rsa->_method_mod_p != NULL)
907 BN_MONT_CTX_free(rsa->_method_mod_p);
908 if (rsa->_method_mod_q != NULL)
909 BN_MONT_CTX_free(rsa->_method_mod_q);