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 */
142 RSA_FLAG_FIPS_METHOD, /* flags */
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 (FIPS_mode() && (BN_num_bits(rsa->n) < OPENSSL_RSA_FIPS_MIN_MODULUS_BITS))
180 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT, RSA_R_KEY_SIZE_TOO_SMALL);
184 if (BN_num_bits(rsa->n) > OPENSSL_RSA_MAX_MODULUS_BITS)
186 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT, RSA_R_MODULUS_TOO_LARGE);
190 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)
199 if (BN_num_bits(rsa->e) > OPENSSL_RSA_MAX_PUBEXP_BITS)
201 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT, RSA_R_BAD_E_VALUE);
206 if ((ctx=BN_CTX_new()) == NULL) goto err;
209 ret = BN_CTX_get(ctx);
210 num=BN_num_bytes(rsa->n);
211 buf = OPENSSL_malloc(num);
212 if (!f || !ret || !buf)
214 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,ERR_R_MALLOC_FAILURE);
220 case RSA_PKCS1_PADDING:
221 i=RSA_padding_add_PKCS1_type_2(buf,num,from,flen);
223 #ifndef OPENSSL_NO_SHA
224 case RSA_PKCS1_OAEP_PADDING:
225 i=RSA_padding_add_PKCS1_OAEP(buf,num,from,flen,NULL,0);
228 case RSA_SSLV23_PADDING:
229 i=RSA_padding_add_SSLv23(buf,num,from,flen);
232 i=RSA_padding_add_none(buf,num,from,flen);
235 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
238 if (i <= 0) goto err;
240 if (BN_bin2bn(buf,num,f) == NULL) goto err;
242 if (BN_ucmp(f, rsa->n) >= 0)
244 /* usually the padding functions would catch this */
245 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
249 MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
251 if (!rsa->meth->bn_mod_exp(ret,f,rsa->e,rsa->n,ctx,
252 rsa->_method_mod_n)) goto err;
254 /* put in leading 0 bytes if the number is less than the
255 * length of the modulus */
257 i=BN_bn2bin(ret,&(to[num-j]));
258 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)
285 CRYPTO_r_unlock(CRYPTO_LOCK_RSA);
286 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
289 if (rsa->blinding == NULL)
290 rsa->blinding = RSA_setup_blinding(rsa, ctx);
297 if (BN_BLINDING_get_thread_id(ret) == CRYPTO_thread_id())
299 /* rsa->blinding is ours! */
305 /* resort to rsa->mt_blinding instead */
307 *local = 0; /* instructs rsa_blinding_convert(), rsa_blinding_invert()
308 * that the BN_BLINDING is shared, meaning that accesses
309 * require locks, and that the blinding factor must be
310 * stored outside the BN_BLINDING
313 if (rsa->mt_blinding == NULL)
317 CRYPTO_r_unlock(CRYPTO_LOCK_RSA);
318 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
322 if (rsa->mt_blinding == NULL)
323 rsa->mt_blinding = RSA_setup_blinding(rsa, ctx);
325 ret = rsa->mt_blinding;
330 CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
332 CRYPTO_r_unlock(CRYPTO_LOCK_RSA);
336 static int rsa_blinding_convert(BN_BLINDING *b, int local, BIGNUM *f,
337 BIGNUM *r, BN_CTX *ctx)
340 return BN_BLINDING_convert_ex(f, NULL, b, ctx);
344 CRYPTO_r_lock(CRYPTO_LOCK_RSA_BLINDING);
345 ret = BN_BLINDING_convert_ex(f, r, b, ctx);
346 CRYPTO_r_unlock(CRYPTO_LOCK_RSA_BLINDING);
351 static int rsa_blinding_invert(BN_BLINDING *b, int local, BIGNUM *f,
352 BIGNUM *r, BN_CTX *ctx)
355 return BN_BLINDING_invert_ex(f, NULL, b, ctx);
359 CRYPTO_w_lock(CRYPTO_LOCK_RSA_BLINDING);
360 ret = BN_BLINDING_invert_ex(f, r, b, ctx);
361 CRYPTO_w_unlock(CRYPTO_LOCK_RSA_BLINDING);
367 static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
368 unsigned char *to, RSA *rsa, int padding)
370 BIGNUM *f, *ret, *br, *res;
371 int i,j,k,num=0,r= -1;
372 unsigned char *buf=NULL;
374 int local_blinding = 0;
375 BN_BLINDING *blinding = NULL;
377 if(FIPS_selftest_failed())
379 FIPSerr(FIPS_F_RSA_EAY_PRIVATE_ENCRYPT,FIPS_R_FIPS_SELFTEST_FAILED);
383 if (FIPS_mode() && (BN_num_bits(rsa->n) < OPENSSL_RSA_FIPS_MIN_MODULUS_BITS))
385 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT, RSA_R_KEY_SIZE_TOO_SMALL);
389 if ((ctx=BN_CTX_new()) == NULL) goto err;
392 br = BN_CTX_get(ctx);
393 ret = BN_CTX_get(ctx);
394 num = BN_num_bytes(rsa->n);
395 buf = OPENSSL_malloc(num);
396 if(!f || !ret || !buf)
398 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,ERR_R_MALLOC_FAILURE);
404 case RSA_PKCS1_PADDING:
405 i=RSA_padding_add_PKCS1_type_1(buf,num,from,flen);
407 case RSA_X931_PADDING:
408 i=RSA_padding_add_X931(buf,num,from,flen);
411 i=RSA_padding_add_none(buf,num,from,flen);
413 case RSA_SSLV23_PADDING:
415 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
418 if (i <= 0) goto err;
420 if (BN_bin2bn(buf,num,f) == NULL) goto err;
422 if (BN_ucmp(f, rsa->n) >= 0)
424 /* usually the padding functions would catch this */
425 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
429 if (!(rsa->flags & RSA_FLAG_NO_BLINDING))
431 blinding = rsa_get_blinding(rsa, &local_blinding, ctx);
432 if (blinding == NULL)
434 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT, ERR_R_INTERNAL_ERROR);
439 if (blinding != NULL)
440 if (!rsa_blinding_convert(blinding, local_blinding, f, br, ctx))
443 if ( (rsa->flags & RSA_FLAG_EXT_PKEY) ||
446 (rsa->dmp1 != NULL) &&
447 (rsa->dmq1 != NULL) &&
448 (rsa->iqmp != NULL)) )
450 if (!rsa->meth->rsa_mod_exp(ret, f, rsa, ctx)) goto err;
457 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
461 BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
466 MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
468 if (!rsa->meth->bn_mod_exp(ret,f,d,rsa->n,ctx,
469 rsa->_method_mod_n)) goto err;
473 if (!rsa_blinding_invert(blinding, local_blinding, ret, br, ctx))
476 if (padding == RSA_X931_PADDING)
478 BN_sub(f, rsa->n, ret);
487 /* put in leading 0 bytes if the number is less than the
488 * length of the modulus */
490 i=BN_bn2bin(res,&(to[num-j]));
491 for (k=0; k<(num-i); k++)
503 OPENSSL_cleanse(buf,num);
509 static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
510 unsigned char *to, RSA *rsa, int padding)
512 BIGNUM *f, *ret, *br;
515 unsigned char *buf=NULL;
517 int local_blinding = 0;
518 BN_BLINDING *blinding = NULL;
520 if(FIPS_selftest_failed())
522 FIPSerr(FIPS_F_RSA_EAY_PRIVATE_DECRYPT,FIPS_R_FIPS_SELFTEST_FAILED);
526 if (FIPS_mode() && (BN_num_bits(rsa->n) < OPENSSL_RSA_FIPS_MIN_MODULUS_BITS))
528 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT, RSA_R_KEY_SIZE_TOO_SMALL);
532 if((ctx = BN_CTX_new()) == NULL) goto err;
535 br = BN_CTX_get(ctx);
536 ret = BN_CTX_get(ctx);
537 num = BN_num_bytes(rsa->n);
538 buf = OPENSSL_malloc(num);
539 if(!f || !ret || !buf)
541 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,ERR_R_MALLOC_FAILURE);
545 /* This check was for equality but PGP does evil things
546 * and chops off the top '0' bytes */
549 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_DATA_GREATER_THAN_MOD_LEN);
553 /* make data into a big number */
554 if (BN_bin2bn(from,(int)flen,f) == NULL) goto err;
556 if (BN_ucmp(f, rsa->n) >= 0)
558 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
562 if (!(rsa->flags & RSA_FLAG_NO_BLINDING))
564 blinding = rsa_get_blinding(rsa, &local_blinding, ctx);
565 if (blinding == NULL)
567 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT, ERR_R_INTERNAL_ERROR);
572 if (blinding != NULL)
573 if (!rsa_blinding_convert(blinding, local_blinding, f, br, ctx))
577 if ( (rsa->flags & RSA_FLAG_EXT_PKEY) ||
580 (rsa->dmp1 != NULL) &&
581 (rsa->dmq1 != NULL) &&
582 (rsa->iqmp != NULL)) )
584 if (!rsa->meth->rsa_mod_exp(ret, f, rsa, ctx)) goto err;
591 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
594 BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
599 MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
600 if (!rsa->meth->bn_mod_exp(ret,f,d,rsa->n,ctx,
606 if (!rsa_blinding_invert(blinding, local_blinding, ret, br, ctx))
610 j=BN_bn2bin(ret,p); /* j is only used with no-padding mode */
614 case RSA_PKCS1_PADDING:
615 r=RSA_padding_check_PKCS1_type_2(to,num,buf,j,num);
617 #ifndef OPENSSL_NO_SHA
618 case RSA_PKCS1_OAEP_PADDING:
619 r=RSA_padding_check_PKCS1_OAEP(to,num,buf,j,num,NULL,0);
622 case RSA_SSLV23_PADDING:
623 r=RSA_padding_check_SSLv23(to,num,buf,j,num);
626 r=RSA_padding_check_none(to,num,buf,j,num);
629 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
633 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_PADDING_CHECK_FAILED);
643 OPENSSL_cleanse(buf,num);
649 /* signature verification */
650 static int RSA_eay_public_decrypt(int flen, const unsigned char *from,
651 unsigned char *to, RSA *rsa, int padding)
656 unsigned char *buf=NULL;
659 if(FIPS_selftest_failed())
661 FIPSerr(FIPS_F_RSA_EAY_PUBLIC_DECRYPT,FIPS_R_FIPS_SELFTEST_FAILED);
665 if (FIPS_mode() && (BN_num_bits(rsa->n) < OPENSSL_RSA_FIPS_MIN_MODULUS_BITS))
667 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_KEY_SIZE_TOO_SMALL);
671 if (BN_num_bits(rsa->n) > OPENSSL_RSA_MAX_MODULUS_BITS)
673 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_MODULUS_TOO_LARGE);
677 if (BN_ucmp(rsa->n, rsa->e) <= 0)
679 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_BAD_E_VALUE);
683 /* for large moduli, enforce exponent limit */
684 if (BN_num_bits(rsa->n) > OPENSSL_RSA_SMALL_MODULUS_BITS)
686 if (BN_num_bits(rsa->e) > OPENSSL_RSA_MAX_PUBEXP_BITS)
688 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_BAD_E_VALUE);
693 if((ctx = BN_CTX_new()) == NULL) goto err;
696 ret = BN_CTX_get(ctx);
697 num=BN_num_bytes(rsa->n);
698 buf = OPENSSL_malloc(num);
699 if(!f || !ret || !buf)
701 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,ERR_R_MALLOC_FAILURE);
705 /* This check was for equality but PGP does evil things
706 * and chops off the top '0' bytes */
709 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_DATA_GREATER_THAN_MOD_LEN);
713 if (BN_bin2bn(from,flen,f) == NULL) goto err;
715 if (BN_ucmp(f, rsa->n) >= 0)
717 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
721 MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
723 if (!rsa->meth->bn_mod_exp(ret,f,rsa->e,rsa->n,ctx,
724 rsa->_method_mod_n)) goto err;
726 if ((padding == RSA_X931_PADDING) && ((ret->d[0] & 0xf) != 12))
727 BN_sub(ret, rsa->n, ret);
734 case RSA_PKCS1_PADDING:
735 r=RSA_padding_check_PKCS1_type_1(to,num,buf,i,num);
737 case RSA_X931_PADDING:
738 r=RSA_padding_check_X931(to,num,buf,i,num);
741 r=RSA_padding_check_none(to,num,buf,i,num);
744 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
748 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_PADDING_CHECK_FAILED);
758 OPENSSL_cleanse(buf,num);
764 static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa, BN_CTX *ctx)
766 BIGNUM *r1,*m1,*vrfy;
767 BIGNUM local_dmp1,local_dmq1,local_c,local_r1;
768 BIGNUM *dmp1,*dmq1,*c,*pr1;
773 r1 = BN_CTX_get(ctx);
774 m1 = BN_CTX_get(ctx);
775 vrfy = BN_CTX_get(ctx);
777 /* Make sure mod_inverse in montgomerey intialization use correct
778 * BN_FLG_CONSTTIME flag.
780 bn_flags = rsa->p->flags;
781 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
783 rsa->p->flags |= BN_FLG_CONSTTIME;
785 MONT_HELPER(rsa, ctx, p, rsa->flags & RSA_FLAG_CACHE_PRIVATE, goto err);
786 /* We restore bn_flags back */
787 rsa->p->flags = bn_flags;
789 /* Make sure mod_inverse in montgomerey intialization use correct
790 * BN_FLG_CONSTTIME flag.
792 bn_flags = rsa->q->flags;
793 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
795 rsa->q->flags |= BN_FLG_CONSTTIME;
797 MONT_HELPER(rsa, ctx, q, rsa->flags & RSA_FLAG_CACHE_PRIVATE, goto err);
798 /* We restore bn_flags back */
799 rsa->q->flags = bn_flags;
801 MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
803 /* compute I mod q */
804 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
807 BN_with_flags(c, I, BN_FLG_CONSTTIME);
808 if (!BN_mod(r1,c,rsa->q,ctx)) goto err;
812 if (!BN_mod(r1,I,rsa->q,ctx)) goto err;
815 /* compute r1^dmq1 mod q */
816 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
819 BN_with_flags(dmq1, rsa->dmq1, BN_FLG_CONSTTIME);
823 if (!rsa->meth->bn_mod_exp(m1,r1,dmq1,rsa->q,ctx,
824 rsa->_method_mod_q)) goto err;
826 /* compute I mod p */
827 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
830 BN_with_flags(c, I, BN_FLG_CONSTTIME);
831 if (!BN_mod(r1,c,rsa->p,ctx)) goto err;
835 if (!BN_mod(r1,I,rsa->p,ctx)) goto err;
838 /* compute r1^dmp1 mod p */
839 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
842 BN_with_flags(dmp1, rsa->dmp1, BN_FLG_CONSTTIME);
846 if (!rsa->meth->bn_mod_exp(r0,r1,dmp1,rsa->p,ctx,
847 rsa->_method_mod_p)) goto err;
849 if (!BN_sub(r0,r0,m1)) goto err;
850 /* This will help stop the size of r0 increasing, which does
851 * affect the multiply if it optimised for a power of 2 size */
852 if (BN_is_negative(r0))
853 if (!BN_add(r0,r0,rsa->p)) goto err;
855 if (!BN_mul(r1,r0,rsa->iqmp,ctx)) goto err;
857 /* Turn BN_FLG_CONSTTIME flag on before division operation */
858 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
861 BN_with_flags(pr1, r1, BN_FLG_CONSTTIME);
865 if (!BN_mod(r0,pr1,rsa->p,ctx)) goto err;
867 /* If p < q it is occasionally possible for the correction of
868 * adding 'p' if r0 is negative above to leave the result still
869 * negative. This can break the private key operations: the following
870 * second correction should *always* correct this rare occurrence.
871 * This will *never* happen with OpenSSL generated keys because
872 * they ensure p > q [steve]
874 if (BN_is_negative(r0))
875 if (!BN_add(r0,r0,rsa->p)) goto err;
876 if (!BN_mul(r1,r0,rsa->q,ctx)) goto err;
877 if (!BN_add(r0,r1,m1)) goto err;
879 if (rsa->e && rsa->n)
881 if (!rsa->meth->bn_mod_exp(vrfy,r0,rsa->e,rsa->n,ctx,rsa->_method_mod_n)) goto err;
882 /* If 'I' was greater than (or equal to) rsa->n, the operation
883 * will be equivalent to using 'I mod n'. However, the result of
884 * the verify will *always* be less than 'n' so we don't check
885 * for absolute equality, just congruency. */
886 if (!BN_sub(vrfy, vrfy, I)) goto err;
887 if (!BN_mod(vrfy, vrfy, rsa->n, ctx)) goto err;
888 if (BN_is_negative(vrfy))
889 if (!BN_add(vrfy, vrfy, rsa->n)) goto err;
890 if (!BN_is_zero(vrfy))
892 /* 'I' and 'vrfy' aren't congruent mod n. Don't leak
893 * miscalculated CRT output, just do a raw (slower)
894 * mod_exp and return that instead. */
899 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
902 BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
906 if (!rsa->meth->bn_mod_exp(r0,I,d,rsa->n,ctx,
907 rsa->_method_mod_n)) goto err;
916 static int RSA_eay_init(RSA *rsa)
918 FIPS_selftest_check();
919 rsa->flags|=RSA_FLAG_CACHE_PUBLIC|RSA_FLAG_CACHE_PRIVATE;
923 static int RSA_eay_finish(RSA *rsa)
925 if (rsa->_method_mod_n != NULL)
926 BN_MONT_CTX_free(rsa->_method_mod_n);
927 if (rsa->_method_mod_p != NULL)
928 BN_MONT_CTX_free(rsa->_method_mod_p);
929 if (rsa->_method_mod_q != NULL)
930 BN_MONT_CTX_free(rsa->_method_mod_q);