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, BN_CTX *ctx);
130 static int RSA_eay_init(RSA *rsa);
131 static int RSA_eay_finish(RSA *rsa);
132 static RSA_METHOD rsa_pkcs1_eay_meth={
133 "Eric Young's PKCS#1 RSA",
134 RSA_eay_public_encrypt,
135 RSA_eay_public_decrypt, /* signature verification */
136 RSA_eay_private_encrypt, /* signing */
137 RSA_eay_private_decrypt,
139 BN_mod_exp_mont, /* XXX probably we should not use Montgomery if e == 3 */
146 NULL /* rsa_keygen */
149 const RSA_METHOD *RSA_PKCS1_SSLeay(void)
151 return(&rsa_pkcs1_eay_meth);
155 * MONT_HELPER(rsa, bn_ctx, p, rsa->flags & RSA_FLAG_CACHE_PRIVATE, goto err);
157 #define MONT_HELPER(rsa, ctx, m, pre_cond, err_instr) \
158 if((pre_cond) && ((rsa)->_method_mod_##m == NULL) && \
159 !BN_MONT_CTX_set_locked(&((rsa)->_method_mod_##m), \
164 static int RSA_eay_public_encrypt(int flen, const unsigned char *from,
165 unsigned char *to, RSA *rsa, int padding)
168 int i,j,k,num=0,r= -1;
169 unsigned char *buf=NULL;
172 if(FIPS_selftest_failed())
174 FIPSerr(FIPS_F_RSA_EAY_PUBLIC_ENCRYPT,FIPS_R_FIPS_SELFTEST_FAILED);
178 if (BN_num_bits(rsa->n) > OPENSSL_RSA_MAX_MODULUS_BITS)
180 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT, RSA_R_MODULUS_TOO_LARGE);
184 if (BN_ucmp(rsa->n, rsa->e) <= 0)
186 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT, RSA_R_BAD_E_VALUE);
190 /* for large moduli, enforce exponent limit */
191 if (BN_num_bits(rsa->n) > OPENSSL_RSA_SMALL_MODULUS_BITS)
193 if (BN_num_bits(rsa->e) > OPENSSL_RSA_MAX_PUBEXP_BITS)
195 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT, RSA_R_BAD_E_VALUE);
200 if ((ctx=BN_CTX_new()) == NULL) goto err;
203 ret = BN_CTX_get(ctx);
204 num=BN_num_bytes(rsa->n);
205 buf = OPENSSL_malloc(num);
206 if (!f || !ret || !buf)
208 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,ERR_R_MALLOC_FAILURE);
214 case RSA_PKCS1_PADDING:
215 i=RSA_padding_add_PKCS1_type_2(buf,num,from,flen);
217 #ifndef OPENSSL_NO_SHA
218 case RSA_PKCS1_OAEP_PADDING:
219 i=RSA_padding_add_PKCS1_OAEP(buf,num,from,flen,NULL,0);
222 case RSA_SSLV23_PADDING:
223 i=RSA_padding_add_SSLv23(buf,num,from,flen);
226 i=RSA_padding_add_none(buf,num,from,flen);
229 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
232 if (i <= 0) goto err;
234 if (BN_bin2bn(buf,num,f) == NULL) goto err;
236 if (BN_ucmp(f, rsa->n) >= 0)
238 /* usually the padding functions would catch this */
239 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
243 MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
245 if (!rsa->meth->bn_mod_exp(ret,f,rsa->e,rsa->n,ctx,
246 rsa->_method_mod_n)) goto err;
248 /* put in leading 0 bytes if the number is less than the
249 * length of the modulus */
251 i=BN_bn2bin(ret,&(to[num-j]));
252 for (k=0; k<(num-i); k++)
264 OPENSSL_cleanse(buf,num);
270 static BN_BLINDING *rsa_get_blinding(RSA *rsa, int *local, BN_CTX *ctx)
273 int got_write_lock = 0;
275 CRYPTO_r_lock(CRYPTO_LOCK_RSA);
277 if (rsa->blinding == NULL)
279 CRYPTO_r_unlock(CRYPTO_LOCK_RSA);
280 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
283 if (rsa->blinding == NULL)
284 rsa->blinding = RSA_setup_blinding(rsa, ctx);
291 if (BN_BLINDING_get_thread_id(ret) == CRYPTO_thread_id())
293 /* rsa->blinding is ours! */
299 /* resort to rsa->mt_blinding instead */
301 *local = 0; /* instructs rsa_blinding_convert(), rsa_blinding_invert()
302 * that the BN_BLINDING is shared, meaning that accesses
303 * require locks, and that the blinding factor must be
304 * stored outside the BN_BLINDING
307 if (rsa->mt_blinding == NULL)
311 CRYPTO_r_unlock(CRYPTO_LOCK_RSA);
312 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
316 if (rsa->mt_blinding == NULL)
317 rsa->mt_blinding = RSA_setup_blinding(rsa, ctx);
319 ret = rsa->mt_blinding;
324 CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
326 CRYPTO_r_unlock(CRYPTO_LOCK_RSA);
330 static int rsa_blinding_convert(BN_BLINDING *b, int local, BIGNUM *f,
331 BIGNUM *r, BN_CTX *ctx)
334 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);
353 CRYPTO_w_lock(CRYPTO_LOCK_RSA_BLINDING);
354 ret = BN_BLINDING_invert_ex(f, r, b, ctx);
355 CRYPTO_w_unlock(CRYPTO_LOCK_RSA_BLINDING);
361 static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
362 unsigned char *to, RSA *rsa, int padding)
364 BIGNUM *f, *ret, *br, *res;
365 int i,j,k,num=0,r= -1;
366 unsigned char *buf=NULL;
368 int local_blinding = 0;
369 BN_BLINDING *blinding = NULL;
371 if(FIPS_selftest_failed())
373 FIPSerr(FIPS_F_RSA_EAY_PUBLIC_ENCRYPT,FIPS_R_FIPS_SELFTEST_FAILED);
377 if ((ctx=BN_CTX_new()) == NULL) goto err;
380 br = BN_CTX_get(ctx);
381 ret = BN_CTX_get(ctx);
382 num = BN_num_bytes(rsa->n);
383 buf = OPENSSL_malloc(num);
384 if(!f || !ret || !buf)
386 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,ERR_R_MALLOC_FAILURE);
392 case RSA_PKCS1_PADDING:
393 i=RSA_padding_add_PKCS1_type_1(buf,num,from,flen);
395 case RSA_X931_PADDING:
396 i=RSA_padding_add_X931(buf,num,from,flen);
399 i=RSA_padding_add_none(buf,num,from,flen);
401 case RSA_SSLV23_PADDING:
403 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
406 if (i <= 0) goto err;
408 if (BN_bin2bn(buf,num,f) == NULL) goto err;
410 if (BN_ucmp(f, rsa->n) >= 0)
412 /* usually the padding functions would catch this */
413 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
417 if (!(rsa->flags & RSA_FLAG_NO_BLINDING))
419 blinding = rsa_get_blinding(rsa, &local_blinding, ctx);
420 if (blinding == NULL)
422 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT, ERR_R_INTERNAL_ERROR);
427 if (blinding != NULL)
428 if (!rsa_blinding_convert(blinding, local_blinding, f, br, ctx))
431 if ( (rsa->flags & RSA_FLAG_EXT_PKEY) ||
434 (rsa->dmp1 != NULL) &&
435 (rsa->dmq1 != NULL) &&
436 (rsa->iqmp != NULL)) )
438 if (!rsa->meth->rsa_mod_exp(ret, f, rsa, ctx)) goto err;
445 if (!(rsa->flags & RSA_FLAG_NO_EXP_CONSTTIME))
449 BN_with_flags(d, rsa->d, BN_FLG_EXP_CONSTTIME);
454 MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
456 if (!rsa->meth->bn_mod_exp(ret,f,d,rsa->n,ctx,
457 rsa->_method_mod_n)) goto err;
461 if (!rsa_blinding_invert(blinding, local_blinding, ret, br, ctx))
464 if (padding == RSA_X931_PADDING)
466 BN_sub(f, rsa->n, ret);
475 /* put in leading 0 bytes if the number is less than the
476 * length of the modulus */
478 i=BN_bn2bin(res,&(to[num-j]));
479 for (k=0; k<(num-i); k++)
491 OPENSSL_cleanse(buf,num);
497 static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
498 unsigned char *to, RSA *rsa, int padding)
500 BIGNUM *f, *ret, *br;
503 unsigned char *buf=NULL;
505 int local_blinding = 0;
506 BN_BLINDING *blinding = NULL;
508 if(FIPS_selftest_failed())
510 FIPSerr(FIPS_F_RSA_EAY_PUBLIC_ENCRYPT,FIPS_R_FIPS_SELFTEST_FAILED);
514 if((ctx = BN_CTX_new()) == NULL) goto err;
517 br = BN_CTX_get(ctx);
518 ret = BN_CTX_get(ctx);
519 num = BN_num_bytes(rsa->n);
520 buf = OPENSSL_malloc(num);
521 if(!f || !ret || !buf)
523 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,ERR_R_MALLOC_FAILURE);
527 /* This check was for equality but PGP does evil things
528 * and chops off the top '0' bytes */
531 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_DATA_GREATER_THAN_MOD_LEN);
535 /* make data into a big number */
536 if (BN_bin2bn(from,(int)flen,f) == NULL) goto err;
538 if (BN_ucmp(f, rsa->n) >= 0)
540 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
544 if (!(rsa->flags & RSA_FLAG_NO_BLINDING))
546 blinding = rsa_get_blinding(rsa, &local_blinding, ctx);
547 if (blinding == NULL)
549 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT, ERR_R_INTERNAL_ERROR);
554 if (blinding != NULL)
555 if (!rsa_blinding_convert(blinding, local_blinding, f, br, ctx))
559 if ( (rsa->flags & RSA_FLAG_EXT_PKEY) ||
562 (rsa->dmp1 != NULL) &&
563 (rsa->dmq1 != NULL) &&
564 (rsa->iqmp != NULL)) )
566 if (!rsa->meth->rsa_mod_exp(ret, f, rsa, ctx)) goto err;
573 if (!(rsa->flags & RSA_FLAG_NO_EXP_CONSTTIME))
576 BN_with_flags(d, rsa->d, BN_FLG_EXP_CONSTTIME);
581 MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
582 if (!rsa->meth->bn_mod_exp(ret,f,d,rsa->n,ctx,
588 if (!rsa_blinding_invert(blinding, local_blinding, ret, br, ctx))
592 j=BN_bn2bin(ret,p); /* j is only used with no-padding mode */
596 case RSA_PKCS1_PADDING:
597 r=RSA_padding_check_PKCS1_type_2(to,num,buf,j,num);
599 #ifndef OPENSSL_NO_SHA
600 case RSA_PKCS1_OAEP_PADDING:
601 r=RSA_padding_check_PKCS1_OAEP(to,num,buf,j,num,NULL,0);
604 case RSA_SSLV23_PADDING:
605 r=RSA_padding_check_SSLv23(to,num,buf,j,num);
608 r=RSA_padding_check_none(to,num,buf,j,num);
611 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
615 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_PADDING_CHECK_FAILED);
625 OPENSSL_cleanse(buf,num);
631 /* signature verification */
632 static int RSA_eay_public_decrypt(int flen, const unsigned char *from,
633 unsigned char *to, RSA *rsa, int padding)
638 unsigned char *buf=NULL;
641 if(FIPS_selftest_failed())
643 FIPSerr(FIPS_F_RSA_EAY_PUBLIC_ENCRYPT,FIPS_R_FIPS_SELFTEST_FAILED);
647 if (BN_num_bits(rsa->n) > OPENSSL_RSA_MAX_MODULUS_BITS)
649 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_MODULUS_TOO_LARGE);
653 if (BN_ucmp(rsa->n, rsa->e) <= 0)
655 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_BAD_E_VALUE);
659 /* for large moduli, enforce exponent limit */
660 if (BN_num_bits(rsa->n) > OPENSSL_RSA_SMALL_MODULUS_BITS)
662 if (BN_num_bits(rsa->e) > OPENSSL_RSA_MAX_PUBEXP_BITS)
664 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_BAD_E_VALUE);
669 if((ctx = BN_CTX_new()) == NULL) goto err;
672 ret = BN_CTX_get(ctx);
673 num=BN_num_bytes(rsa->n);
674 buf = OPENSSL_malloc(num);
675 if(!f || !ret || !buf)
677 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,ERR_R_MALLOC_FAILURE);
681 /* This check was for equality but PGP does evil things
682 * and chops off the top '0' bytes */
685 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_DATA_GREATER_THAN_MOD_LEN);
689 if (BN_bin2bn(from,flen,f) == NULL) goto err;
691 if (BN_ucmp(f, rsa->n) >= 0)
693 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
697 MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
699 if (!rsa->meth->bn_mod_exp(ret,f,rsa->e,rsa->n,ctx,
700 rsa->_method_mod_n)) goto err;
702 if ((padding == RSA_X931_PADDING) && ((ret->d[0] & 0xf) != 12))
703 BN_sub(ret, rsa->n, ret);
710 case RSA_PKCS1_PADDING:
711 r=RSA_padding_check_PKCS1_type_1(to,num,buf,i,num);
713 case RSA_X931_PADDING:
714 r=RSA_padding_check_X931(to,num,buf,i,num);
717 r=RSA_padding_check_none(to,num,buf,i,num);
720 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
724 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_PADDING_CHECK_FAILED);
734 OPENSSL_cleanse(buf,num);
740 static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa, BN_CTX *ctx)
742 BIGNUM *r1,*m1,*vrfy;
743 BIGNUM local_dmp1, local_dmq1;
748 r1 = BN_CTX_get(ctx);
749 m1 = BN_CTX_get(ctx);
750 vrfy = BN_CTX_get(ctx);
752 MONT_HELPER(rsa, ctx, p, rsa->flags & RSA_FLAG_CACHE_PRIVATE, goto err);
753 MONT_HELPER(rsa, ctx, q, rsa->flags & RSA_FLAG_CACHE_PRIVATE, goto err);
754 MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
756 if (!BN_mod(r1,I,rsa->q,ctx)) goto err;
757 if (!(rsa->flags & RSA_FLAG_NO_EXP_CONSTTIME))
760 BN_with_flags(dmq1, rsa->dmq1, BN_FLG_EXP_CONSTTIME);
764 if (!rsa->meth->bn_mod_exp(m1,r1,dmq1,rsa->q,ctx,
765 rsa->_method_mod_q)) goto err;
767 if (!BN_mod(r1,I,rsa->p,ctx)) goto err;
768 if (!(rsa->flags & RSA_FLAG_NO_EXP_CONSTTIME))
771 BN_with_flags(dmp1, rsa->dmp1, BN_FLG_EXP_CONSTTIME);
775 if (!rsa->meth->bn_mod_exp(r0,r1,dmp1,rsa->p,ctx,
776 rsa->_method_mod_p)) goto err;
778 if (!BN_sub(r0,r0,m1)) goto err;
779 /* This will help stop the size of r0 increasing, which does
780 * affect the multiply if it optimised for a power of 2 size */
781 if (BN_is_negative(r0))
782 if (!BN_add(r0,r0,rsa->p)) goto err;
784 if (!BN_mul(r1,r0,rsa->iqmp,ctx)) goto err;
785 if (!BN_mod(r0,r1,rsa->p,ctx)) goto err;
786 /* If p < q it is occasionally possible for the correction of
787 * adding 'p' if r0 is negative above to leave the result still
788 * negative. This can break the private key operations: the following
789 * second correction should *always* correct this rare occurrence.
790 * This will *never* happen with OpenSSL generated keys because
791 * they ensure p > q [steve]
793 if (BN_is_negative(r0))
794 if (!BN_add(r0,r0,rsa->p)) goto err;
795 if (!BN_mul(r1,r0,rsa->q,ctx)) goto err;
796 if (!BN_add(r0,r1,m1)) goto err;
798 if (rsa->e && rsa->n)
800 if (!rsa->meth->bn_mod_exp(vrfy,r0,rsa->e,rsa->n,ctx,rsa->_method_mod_n)) goto err;
801 /* If 'I' was greater than (or equal to) rsa->n, the operation
802 * will be equivalent to using 'I mod n'. However, the result of
803 * the verify will *always* be less than 'n' so we don't check
804 * for absolute equality, just congruency. */
805 if (!BN_sub(vrfy, vrfy, I)) goto err;
806 if (!BN_mod(vrfy, vrfy, rsa->n, ctx)) goto err;
807 if (BN_is_negative(vrfy))
808 if (!BN_add(vrfy, vrfy, rsa->n)) goto err;
809 if (!BN_is_zero(vrfy))
811 /* 'I' and 'vrfy' aren't congruent mod n. Don't leak
812 * miscalculated CRT output, just do a raw (slower)
813 * mod_exp and return that instead. */
818 if (!(rsa->flags & RSA_FLAG_NO_EXP_CONSTTIME))
821 BN_with_flags(d, rsa->d, BN_FLG_EXP_CONSTTIME);
825 if (!rsa->meth->bn_mod_exp(r0,I,d,rsa->n,ctx,
826 rsa->_method_mod_n)) goto err;
835 static int RSA_eay_init(RSA *rsa)
837 rsa->flags|=RSA_FLAG_CACHE_PUBLIC|RSA_FLAG_CACHE_PRIVATE;
841 static int RSA_eay_finish(RSA *rsa)
843 if (rsa->_method_mod_n != NULL)
844 BN_MONT_CTX_free(rsa->_method_mod_n);
845 if (rsa->_method_mod_p != NULL)
846 BN_MONT_CTX_free(rsa->_method_mod_p);
847 if (rsa->_method_mod_q != NULL)
848 BN_MONT_CTX_free(rsa->_method_mod_q);