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 "cryptlib.h"
114 #include <openssl/bn.h>
115 #include <openssl/rsa.h>
116 #include <openssl/rand.h>
120 static int RSA_eay_public_encrypt(int flen, const unsigned char *from,
121 unsigned char *to, RSA *rsa,int padding);
122 static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
123 unsigned char *to, RSA *rsa,int padding);
124 static int RSA_eay_public_decrypt(int flen, const unsigned char *from,
125 unsigned char *to, RSA *rsa,int padding);
126 static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
127 unsigned char *to, RSA *rsa,int padding);
128 static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *i, RSA *rsa, BN_CTX *ctx);
129 static int RSA_eay_init(RSA *rsa);
130 static int RSA_eay_finish(RSA *rsa);
131 static RSA_METHOD rsa_pkcs1_eay_meth={
132 "Eric Young's PKCS#1 RSA",
133 RSA_eay_public_encrypt,
134 RSA_eay_public_decrypt, /* signature verification */
135 RSA_eay_private_encrypt, /* signing */
136 RSA_eay_private_decrypt,
138 BN_mod_exp_mont, /* XXX probably we should not use Montgomery if e == 3 */
145 NULL /* rsa_keygen */
148 const RSA_METHOD *RSA_PKCS1_SSLeay(void)
150 return(&rsa_pkcs1_eay_meth);
154 * MONT_HELPER(rsa, bn_ctx, p, rsa->flags & RSA_FLAG_CACHE_PRIVATE, goto err);
156 #define MONT_HELPER(rsa, ctx, m, pre_cond, err_instr) \
157 if((pre_cond) && ((rsa)->_method_mod_##m == NULL) && \
158 !BN_MONT_CTX_set_locked(&((rsa)->_method_mod_##m), \
163 static int RSA_eay_public_encrypt(int flen, const unsigned char *from,
164 unsigned char *to, RSA *rsa, int padding)
167 int i,j,k,num=0,r= -1;
168 unsigned char *buf=NULL;
171 if (BN_num_bits(rsa->n) > OPENSSL_RSA_MAX_MODULUS_BITS)
173 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT, RSA_R_MODULUS_TOO_LARGE);
177 if (BN_ucmp(rsa->n, rsa->e) <= 0)
179 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT, RSA_R_BAD_E_VALUE);
183 /* for large moduli, enforce exponent limit */
184 if (BN_num_bits(rsa->n) > OPENSSL_RSA_SMALL_MODULUS_BITS)
186 if (BN_num_bits(rsa->e) > OPENSSL_RSA_MAX_PUBEXP_BITS)
188 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT, RSA_R_BAD_E_VALUE);
193 if ((ctx=BN_CTX_new()) == NULL) goto err;
196 ret = BN_CTX_get(ctx);
197 num=BN_num_bytes(rsa->n);
198 buf = OPENSSL_malloc(num);
199 if (!f || !ret || !buf)
201 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,ERR_R_MALLOC_FAILURE);
207 case RSA_PKCS1_PADDING:
208 i=RSA_padding_add_PKCS1_type_2(buf,num,from,flen);
210 #ifndef OPENSSL_NO_SHA
211 case RSA_PKCS1_OAEP_PADDING:
212 i=RSA_padding_add_PKCS1_OAEP(buf,num,from,flen,NULL,0);
215 case RSA_SSLV23_PADDING:
216 i=RSA_padding_add_SSLv23(buf,num,from,flen);
219 i=RSA_padding_add_none(buf,num,from,flen);
222 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
225 if (i <= 0) goto err;
227 if (BN_bin2bn(buf,num,f) == NULL) goto err;
229 if (BN_ucmp(f, rsa->n) >= 0)
231 /* usually the padding functions would catch this */
232 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
236 MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
238 if (!rsa->meth->bn_mod_exp(ret,f,rsa->e,rsa->n,ctx,
239 rsa->_method_mod_n)) goto err;
241 /* put in leading 0 bytes if the number is less than the
242 * length of the modulus */
244 i=BN_bn2bin(ret,&(to[num-j]));
245 for (k=0; k<(num-i); k++)
257 OPENSSL_cleanse(buf,num);
263 static BN_BLINDING *rsa_get_blinding(RSA *rsa, int *local, BN_CTX *ctx)
266 int got_write_lock = 0;
268 CRYPTO_r_lock(CRYPTO_LOCK_RSA);
270 if (rsa->blinding == NULL)
272 CRYPTO_r_unlock(CRYPTO_LOCK_RSA);
273 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
276 if (rsa->blinding == NULL)
277 rsa->blinding = RSA_setup_blinding(rsa, ctx);
284 if ((BN_BLINDING_get_thread_id(ret) == CRYPTO_thread_id()) && (BN_BLINDING_get_thread_idptr(ret) == CRYPTO_thread_idptr()))
286 /* rsa->blinding is ours! */
292 /* resort to rsa->mt_blinding instead */
294 *local = 0; /* instructs rsa_blinding_convert(), rsa_blinding_invert()
295 * that the BN_BLINDING is shared, meaning that accesses
296 * require locks, and that the blinding factor must be
297 * stored outside the BN_BLINDING
300 if (rsa->mt_blinding == NULL)
304 CRYPTO_r_unlock(CRYPTO_LOCK_RSA);
305 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
309 if (rsa->mt_blinding == NULL)
310 rsa->mt_blinding = RSA_setup_blinding(rsa, ctx);
312 ret = rsa->mt_blinding;
317 CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
319 CRYPTO_r_unlock(CRYPTO_LOCK_RSA);
323 static int rsa_blinding_convert(BN_BLINDING *b, int local, BIGNUM *f,
324 BIGNUM *r, BN_CTX *ctx)
327 return BN_BLINDING_convert_ex(f, NULL, b, ctx);
331 CRYPTO_r_lock(CRYPTO_LOCK_RSA_BLINDING);
332 ret = BN_BLINDING_convert_ex(f, r, b, ctx);
333 CRYPTO_r_unlock(CRYPTO_LOCK_RSA_BLINDING);
338 static int rsa_blinding_invert(BN_BLINDING *b, int local, BIGNUM *f,
339 BIGNUM *r, BN_CTX *ctx)
342 return BN_BLINDING_invert_ex(f, NULL, b, ctx);
346 CRYPTO_w_lock(CRYPTO_LOCK_RSA_BLINDING);
347 ret = BN_BLINDING_invert_ex(f, r, b, ctx);
348 CRYPTO_w_unlock(CRYPTO_LOCK_RSA_BLINDING);
354 static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
355 unsigned char *to, RSA *rsa, int padding)
357 BIGNUM *f, *ret, *br, *res;
358 int i,j,k,num=0,r= -1;
359 unsigned char *buf=NULL;
361 int local_blinding = 0;
362 BN_BLINDING *blinding = NULL;
364 if ((ctx=BN_CTX_new()) == NULL) goto err;
367 br = BN_CTX_get(ctx);
368 ret = BN_CTX_get(ctx);
369 num = BN_num_bytes(rsa->n);
370 buf = OPENSSL_malloc(num);
371 if(!f || !ret || !buf)
373 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,ERR_R_MALLOC_FAILURE);
379 case RSA_PKCS1_PADDING:
380 i=RSA_padding_add_PKCS1_type_1(buf,num,from,flen);
382 case RSA_X931_PADDING:
383 i=RSA_padding_add_X931(buf,num,from,flen);
386 i=RSA_padding_add_none(buf,num,from,flen);
388 case RSA_SSLV23_PADDING:
390 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
393 if (i <= 0) goto err;
395 if (BN_bin2bn(buf,num,f) == NULL) goto err;
397 if (BN_ucmp(f, rsa->n) >= 0)
399 /* usually the padding functions would catch this */
400 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
404 if (!(rsa->flags & RSA_FLAG_NO_BLINDING))
406 blinding = rsa_get_blinding(rsa, &local_blinding, ctx);
407 if (blinding == NULL)
409 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT, ERR_R_INTERNAL_ERROR);
414 if (blinding != NULL)
415 if (!rsa_blinding_convert(blinding, local_blinding, f, br, ctx))
418 if ( (rsa->flags & RSA_FLAG_EXT_PKEY) ||
421 (rsa->dmp1 != NULL) &&
422 (rsa->dmq1 != NULL) &&
423 (rsa->iqmp != NULL)) )
425 if (!rsa->meth->rsa_mod_exp(ret, f, rsa, ctx)) goto err;
432 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
436 BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
441 MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
443 if (!rsa->meth->bn_mod_exp(ret,f,d,rsa->n,ctx,
444 rsa->_method_mod_n)) goto err;
448 if (!rsa_blinding_invert(blinding, local_blinding, ret, br, ctx))
451 if (padding == RSA_X931_PADDING)
453 BN_sub(f, rsa->n, ret);
462 /* put in leading 0 bytes if the number is less than the
463 * length of the modulus */
465 i=BN_bn2bin(res,&(to[num-j]));
466 for (k=0; k<(num-i); k++)
478 OPENSSL_cleanse(buf,num);
484 static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
485 unsigned char *to, RSA *rsa, int padding)
487 BIGNUM *f, *ret, *br;
490 unsigned char *buf=NULL;
492 int local_blinding = 0;
493 BN_BLINDING *blinding = NULL;
495 if((ctx = BN_CTX_new()) == NULL) goto err;
498 br = BN_CTX_get(ctx);
499 ret = BN_CTX_get(ctx);
500 num = BN_num_bytes(rsa->n);
501 buf = OPENSSL_malloc(num);
502 if(!f || !ret || !buf)
504 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,ERR_R_MALLOC_FAILURE);
508 /* This check was for equality but PGP does evil things
509 * and chops off the top '0' bytes */
512 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_DATA_GREATER_THAN_MOD_LEN);
516 /* make data into a big number */
517 if (BN_bin2bn(from,(int)flen,f) == NULL) goto err;
519 if (BN_ucmp(f, rsa->n) >= 0)
521 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
525 if (!(rsa->flags & RSA_FLAG_NO_BLINDING))
527 blinding = rsa_get_blinding(rsa, &local_blinding, ctx);
528 if (blinding == NULL)
530 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT, ERR_R_INTERNAL_ERROR);
535 if (blinding != NULL)
536 if (!rsa_blinding_convert(blinding, local_blinding, f, br, ctx))
540 if ( (rsa->flags & RSA_FLAG_EXT_PKEY) ||
543 (rsa->dmp1 != NULL) &&
544 (rsa->dmq1 != NULL) &&
545 (rsa->iqmp != NULL)) )
547 if (!rsa->meth->rsa_mod_exp(ret, f, rsa, ctx)) goto err;
554 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
557 BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
562 MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
563 if (!rsa->meth->bn_mod_exp(ret,f,d,rsa->n,ctx,
569 if (!rsa_blinding_invert(blinding, local_blinding, ret, br, ctx))
573 j=BN_bn2bin(ret,p); /* j is only used with no-padding mode */
577 case RSA_PKCS1_PADDING:
578 r=RSA_padding_check_PKCS1_type_2(to,num,buf,j,num);
580 #ifndef OPENSSL_NO_SHA
581 case RSA_PKCS1_OAEP_PADDING:
582 r=RSA_padding_check_PKCS1_OAEP(to,num,buf,j,num,NULL,0);
585 case RSA_SSLV23_PADDING:
586 r=RSA_padding_check_SSLv23(to,num,buf,j,num);
589 r=RSA_padding_check_none(to,num,buf,j,num);
592 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
596 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_PADDING_CHECK_FAILED);
606 OPENSSL_cleanse(buf,num);
612 /* signature verification */
613 static int RSA_eay_public_decrypt(int flen, const unsigned char *from,
614 unsigned char *to, RSA *rsa, int padding)
619 unsigned char *buf=NULL;
622 if (BN_num_bits(rsa->n) > OPENSSL_RSA_MAX_MODULUS_BITS)
624 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_MODULUS_TOO_LARGE);
628 if (BN_ucmp(rsa->n, rsa->e) <= 0)
630 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_BAD_E_VALUE);
634 /* for large moduli, enforce exponent limit */
635 if (BN_num_bits(rsa->n) > OPENSSL_RSA_SMALL_MODULUS_BITS)
637 if (BN_num_bits(rsa->e) > OPENSSL_RSA_MAX_PUBEXP_BITS)
639 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_BAD_E_VALUE);
644 if((ctx = BN_CTX_new()) == NULL) goto err;
647 ret = BN_CTX_get(ctx);
648 num=BN_num_bytes(rsa->n);
649 buf = OPENSSL_malloc(num);
650 if(!f || !ret || !buf)
652 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,ERR_R_MALLOC_FAILURE);
656 /* This check was for equality but PGP does evil things
657 * and chops off the top '0' bytes */
660 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_DATA_GREATER_THAN_MOD_LEN);
664 if (BN_bin2bn(from,flen,f) == NULL) goto err;
666 if (BN_ucmp(f, rsa->n) >= 0)
668 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
672 MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
674 if (!rsa->meth->bn_mod_exp(ret,f,rsa->e,rsa->n,ctx,
675 rsa->_method_mod_n)) goto err;
677 if ((padding == RSA_X931_PADDING) && ((ret->d[0] & 0xf) != 12))
678 BN_sub(ret, rsa->n, ret);
685 case RSA_PKCS1_PADDING:
686 r=RSA_padding_check_PKCS1_type_1(to,num,buf,i,num);
688 case RSA_X931_PADDING:
689 r=RSA_padding_check_X931(to,num,buf,i,num);
692 r=RSA_padding_check_none(to,num,buf,i,num);
695 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
699 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_PADDING_CHECK_FAILED);
709 OPENSSL_cleanse(buf,num);
715 static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa, BN_CTX *ctx)
717 BIGNUM *r1,*m1,*vrfy;
718 BIGNUM local_dmp1,local_dmq1,local_c,local_r1;
719 BIGNUM *dmp1,*dmq1,*c,*pr1;
724 r1 = BN_CTX_get(ctx);
725 m1 = BN_CTX_get(ctx);
726 vrfy = BN_CTX_get(ctx);
728 /* Make sure mod_inverse in montgomerey intialization use correct
729 * BN_FLG_CONSTTIME flag.
731 bn_flags = rsa->p->flags;
732 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
734 rsa->p->flags |= BN_FLG_CONSTTIME;
736 MONT_HELPER(rsa, ctx, p, rsa->flags & RSA_FLAG_CACHE_PRIVATE, goto err);
737 /* We restore bn_flags back */
738 rsa->p->flags = bn_flags;
740 /* Make sure mod_inverse in montgomerey intialization use correct
741 * BN_FLG_CONSTTIME flag.
743 bn_flags = rsa->q->flags;
744 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
746 rsa->q->flags |= BN_FLG_CONSTTIME;
748 MONT_HELPER(rsa, ctx, q, rsa->flags & RSA_FLAG_CACHE_PRIVATE, goto err);
749 /* We restore bn_flags back */
750 rsa->q->flags = bn_flags;
752 MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
754 /* compute I mod q */
755 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
758 BN_with_flags(c, I, BN_FLG_CONSTTIME);
759 if (!BN_mod(r1,c,rsa->q,ctx)) goto err;
763 if (!BN_mod(r1,I,rsa->q,ctx)) goto err;
766 /* compute r1^dmq1 mod q */
767 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
770 BN_with_flags(dmq1, rsa->dmq1, BN_FLG_CONSTTIME);
774 if (!rsa->meth->bn_mod_exp(m1,r1,dmq1,rsa->q,ctx,
775 rsa->_method_mod_q)) goto err;
777 /* compute I mod p */
778 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
781 BN_with_flags(c, I, BN_FLG_CONSTTIME);
782 if (!BN_mod(r1,c,rsa->p,ctx)) goto err;
786 if (!BN_mod(r1,I,rsa->p,ctx)) goto err;
789 /* compute r1^dmp1 mod p */
790 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
793 BN_with_flags(dmp1, rsa->dmp1, BN_FLG_CONSTTIME);
797 if (!rsa->meth->bn_mod_exp(r0,r1,dmp1,rsa->p,ctx,
798 rsa->_method_mod_p)) goto err;
800 if (!BN_sub(r0,r0,m1)) goto err;
801 /* This will help stop the size of r0 increasing, which does
802 * affect the multiply if it optimised for a power of 2 size */
803 if (BN_is_negative(r0))
804 if (!BN_add(r0,r0,rsa->p)) goto err;
806 if (!BN_mul(r1,r0,rsa->iqmp,ctx)) goto err;
808 /* Turn BN_FLG_CONSTTIME flag on before division operation */
809 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
812 BN_with_flags(pr1, r1, BN_FLG_CONSTTIME);
816 if (!BN_mod(r0,pr1,rsa->p,ctx)) goto err;
818 /* If p < q it is occasionally possible for the correction of
819 * adding 'p' if r0 is negative above to leave the result still
820 * negative. This can break the private key operations: the following
821 * second correction should *always* correct this rare occurrence.
822 * This will *never* happen with OpenSSL generated keys because
823 * they ensure p > q [steve]
825 if (BN_is_negative(r0))
826 if (!BN_add(r0,r0,rsa->p)) goto err;
827 if (!BN_mul(r1,r0,rsa->q,ctx)) goto err;
828 if (!BN_add(r0,r1,m1)) goto err;
830 if (rsa->e && rsa->n)
832 if (!rsa->meth->bn_mod_exp(vrfy,r0,rsa->e,rsa->n,ctx,rsa->_method_mod_n)) goto err;
833 /* If 'I' was greater than (or equal to) rsa->n, the operation
834 * will be equivalent to using 'I mod n'. However, the result of
835 * the verify will *always* be less than 'n' so we don't check
836 * for absolute equality, just congruency. */
837 if (!BN_sub(vrfy, vrfy, I)) goto err;
838 if (!BN_mod(vrfy, vrfy, rsa->n, ctx)) goto err;
839 if (BN_is_negative(vrfy))
840 if (!BN_add(vrfy, vrfy, rsa->n)) goto err;
841 if (!BN_is_zero(vrfy))
843 /* 'I' and 'vrfy' aren't congruent mod n. Don't leak
844 * miscalculated CRT output, just do a raw (slower)
845 * mod_exp and return that instead. */
850 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
853 BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
857 if (!rsa->meth->bn_mod_exp(r0,I,d,rsa->n,ctx,
858 rsa->_method_mod_n)) goto err;
867 static int RSA_eay_init(RSA *rsa)
869 rsa->flags|=RSA_FLAG_CACHE_PUBLIC|RSA_FLAG_CACHE_PRIVATE;
873 static int RSA_eay_finish(RSA *rsa)
875 if (rsa->_method_mod_n != NULL)
876 BN_MONT_CTX_free(rsa->_method_mod_n);
877 if (rsa->_method_mod_p != NULL)
878 BN_MONT_CTX_free(rsa->_method_mod_p);
879 if (rsa->_method_mod_q != NULL)
880 BN_MONT_CTX_free(rsa->_method_mod_q);