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.]
61 #include <openssl/bn.h>
62 #include <openssl/rsa.h>
63 #include <openssl/rand.h>
65 #if !defined(RSA_NULL) && !defined(OPENSSL_FIPS)
67 static int RSA_eay_public_encrypt(int flen, const unsigned char *from,
68 unsigned char *to, RSA *rsa,int padding);
69 static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
70 unsigned char *to, RSA *rsa,int padding);
71 static int RSA_eay_public_decrypt(int flen, const unsigned char *from,
72 unsigned char *to, RSA *rsa,int padding);
73 static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
74 unsigned char *to, RSA *rsa,int padding);
75 static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *i, RSA *rsa);
76 static int RSA_eay_init(RSA *rsa);
77 static int RSA_eay_finish(RSA *rsa);
78 static RSA_METHOD rsa_pkcs1_eay_meth={
79 "Eric Young's PKCS#1 RSA",
80 RSA_eay_public_encrypt,
81 RSA_eay_public_decrypt, /* signature verification */
82 RSA_eay_private_encrypt, /* signing */
83 RSA_eay_private_decrypt,
85 BN_mod_exp_mont, /* XXX probably we should not use Montgomery if e == 3 */
94 const RSA_METHOD *RSA_PKCS1_SSLeay(void)
96 return(&rsa_pkcs1_eay_meth);
99 static int RSA_eay_public_encrypt(int flen, const unsigned char *from,
100 unsigned char *to, RSA *rsa, int padding)
103 int i,j,k,num=0,r= -1;
104 unsigned char *buf=NULL;
109 if ((ctx=BN_CTX_new()) == NULL) goto err;
110 num=BN_num_bytes(rsa->n);
111 if ((buf=(unsigned char *)OPENSSL_malloc(num)) == NULL)
113 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,ERR_R_MALLOC_FAILURE);
119 case RSA_PKCS1_PADDING:
120 i=RSA_padding_add_PKCS1_type_2(buf,num,from,flen);
122 #ifndef OPENSSL_NO_SHA
123 case RSA_PKCS1_OAEP_PADDING:
124 i=RSA_padding_add_PKCS1_OAEP(buf,num,from,flen,NULL,0);
127 case RSA_SSLV23_PADDING:
128 i=RSA_padding_add_SSLv23(buf,num,from,flen);
131 i=RSA_padding_add_none(buf,num,from,flen);
134 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
137 if (i <= 0) goto err;
139 if (BN_bin2bn(buf,num,&f) == NULL) goto err;
141 if (BN_ucmp(&f, rsa->n) >= 0)
143 /* usually the padding functions would catch this */
144 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
148 if ((rsa->_method_mod_n == NULL) && (rsa->flags & RSA_FLAG_CACHE_PUBLIC))
150 BN_MONT_CTX* bn_mont_ctx;
151 if ((bn_mont_ctx=BN_MONT_CTX_new()) == NULL)
153 if (!BN_MONT_CTX_set(bn_mont_ctx,rsa->n,ctx))
155 BN_MONT_CTX_free(bn_mont_ctx);
158 if (rsa->_method_mod_n == NULL) /* other thread may have finished first */
160 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
161 if (rsa->_method_mod_n == NULL)
163 rsa->_method_mod_n = bn_mont_ctx;
166 CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
169 BN_MONT_CTX_free(bn_mont_ctx);
172 if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->e,rsa->n,ctx,
173 rsa->_method_mod_n)) goto err;
175 /* put in leading 0 bytes if the number is less than the
176 * length of the modulus */
177 j=BN_num_bytes(&ret);
178 i=BN_bn2bin(&ret,&(to[num-j]));
179 for (k=0; k<(num-i); k++)
184 if (ctx != NULL) BN_CTX_free(ctx);
189 OPENSSL_cleanse(buf,num);
195 static int rsa_eay_blinding(RSA *rsa, BN_CTX *ctx)
198 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
199 /* Check again inside the lock - the macro's check is racey */
200 if(rsa->blinding == NULL)
201 ret = RSA_blinding_on(rsa, ctx);
202 CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
206 #define BLINDING_HELPER(rsa, ctx, err_instr) \
208 if((!((rsa)->flags & RSA_FLAG_NO_BLINDING)) && \
209 ((rsa)->blinding == NULL) && \
210 !rsa_eay_blinding(rsa, ctx)) \
214 static BN_BLINDING *setup_blinding(RSA *rsa, BN_CTX *ctx)
217 BN_BLINDING *ret = NULL;
219 /* added in OpenSSL 0.9.6j and 0.9.7b */
221 /* NB: similar code appears in RSA_blinding_on (rsa_lib.c);
222 * this should be placed in a new function of its own, but for reasons
223 * of binary compatibility can't */
227 if ((RAND_status() == 0) && rsa->d != NULL && rsa->d->d != NULL)
229 /* if PRNG is not properly seeded, resort to secret exponent as unpredictable seed */
230 RAND_add(rsa->d->d, rsa->d->dmax * sizeof rsa->d->d[0], 0);
231 if (!BN_pseudo_rand_range(A,rsa->n)) goto err;
235 if (!BN_rand_range(A,rsa->n)) goto err;
237 if ((Ai=BN_mod_inverse(NULL,A,rsa->n,ctx)) == NULL) goto err;
239 if (!rsa->meth->bn_mod_exp(A,A,rsa->e,rsa->n,ctx,rsa->_method_mod_n))
241 ret = BN_BLINDING_new(A,Ai,rsa->n);
249 static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
250 unsigned char *to, RSA *rsa, int padding)
253 int i,j,k,num=0,r= -1;
254 unsigned char *buf=NULL;
256 int local_blinding = 0;
257 BN_BLINDING *blinding = NULL;
262 if ((ctx=BN_CTX_new()) == NULL) goto err;
263 num=BN_num_bytes(rsa->n);
264 if ((buf=(unsigned char *)OPENSSL_malloc(num)) == NULL)
266 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,ERR_R_MALLOC_FAILURE);
272 case RSA_PKCS1_PADDING:
273 i=RSA_padding_add_PKCS1_type_1(buf,num,from,flen);
276 i=RSA_padding_add_none(buf,num,from,flen);
278 case RSA_SSLV23_PADDING:
280 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
283 if (i <= 0) goto err;
285 if (BN_bin2bn(buf,num,&f) == NULL) goto err;
287 if (BN_ucmp(&f, rsa->n) >= 0)
289 /* usually the padding functions would catch this */
290 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
294 BLINDING_HELPER(rsa, ctx, goto err;);
295 blinding = rsa->blinding;
297 /* Now unless blinding is disabled, 'blinding' is non-NULL.
298 * But the BN_BLINDING object may be owned by some other thread
299 * (we don't want to keep it constant and we don't want to use
300 * lots of locking to avoid race conditions, so only a single
301 * thread can use it; other threads have to use local blinding
303 if (!(rsa->flags & RSA_FLAG_NO_BLINDING))
305 if (blinding == NULL)
307 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT, ERR_R_INTERNAL_ERROR);
312 if (blinding != NULL)
314 if (blinding->thread_id != CRYPTO_thread_id())
316 /* we need a local one-time blinding factor */
318 blinding = setup_blinding(rsa, ctx);
319 if (blinding == NULL)
326 if (!BN_BLINDING_convert(&f, blinding, ctx)) goto err;
328 if ( (rsa->flags & RSA_FLAG_EXT_PKEY) ||
331 (rsa->dmp1 != NULL) &&
332 (rsa->dmq1 != NULL) &&
333 (rsa->iqmp != NULL)) )
334 { if (!rsa->meth->rsa_mod_exp(&ret,&f,rsa)) goto err; }
337 if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->d,rsa->n,ctx,NULL)) goto err;
341 if (!BN_BLINDING_invert(&ret, blinding, ctx)) goto err;
343 /* put in leading 0 bytes if the number is less than the
344 * length of the modulus */
345 j=BN_num_bytes(&ret);
346 i=BN_bn2bin(&ret,&(to[num-j]));
347 for (k=0; k<(num-i); k++)
352 if (ctx != NULL) BN_CTX_free(ctx);
356 BN_BLINDING_free(blinding);
359 OPENSSL_cleanse(buf,num);
365 static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
366 unsigned char *to, RSA *rsa, int padding)
371 unsigned char *buf=NULL;
373 int local_blinding = 0;
374 BN_BLINDING *blinding = NULL;
379 if (ctx == NULL) goto err;
381 num=BN_num_bytes(rsa->n);
383 if ((buf=(unsigned char *)OPENSSL_malloc(num)) == NULL)
385 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,ERR_R_MALLOC_FAILURE);
389 /* This check was for equality but PGP does evil things
390 * and chops off the top '0' bytes */
393 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_DATA_GREATER_THAN_MOD_LEN);
397 /* make data into a big number */
398 if (BN_bin2bn(from,(int)flen,&f) == NULL) goto err;
400 if (BN_ucmp(&f, rsa->n) >= 0)
402 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
406 BLINDING_HELPER(rsa, ctx, goto err;);
407 blinding = rsa->blinding;
409 /* Now unless blinding is disabled, 'blinding' is non-NULL.
410 * But the BN_BLINDING object may be owned by some other thread
411 * (we don't want to keep it constant and we don't want to use
412 * lots of locking to avoid race conditions, so only a single
413 * thread can use it; other threads have to use local blinding
415 if (!(rsa->flags & RSA_FLAG_NO_BLINDING))
417 if (blinding == NULL)
419 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT, ERR_R_INTERNAL_ERROR);
424 if (blinding != NULL)
426 if (blinding->thread_id != CRYPTO_thread_id())
428 /* we need a local one-time blinding factor */
430 blinding = setup_blinding(rsa, ctx);
431 if (blinding == NULL)
438 if (!BN_BLINDING_convert(&f, blinding, ctx)) goto err;
441 if ( (rsa->flags & RSA_FLAG_EXT_PKEY) ||
444 (rsa->dmp1 != NULL) &&
445 (rsa->dmq1 != NULL) &&
446 (rsa->iqmp != NULL)) )
447 { if (!rsa->meth->rsa_mod_exp(&ret,&f,rsa)) goto err; }
450 if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->d,rsa->n,ctx,NULL))
455 if (!BN_BLINDING_invert(&ret, blinding, ctx)) goto err;
458 j=BN_bn2bin(&ret,p); /* j is only used with no-padding mode */
462 case RSA_PKCS1_PADDING:
463 r=RSA_padding_check_PKCS1_type_2(to,num,buf,j,num);
465 #ifndef OPENSSL_NO_SHA
466 case RSA_PKCS1_OAEP_PADDING:
467 r=RSA_padding_check_PKCS1_OAEP(to,num,buf,j,num,NULL,0);
470 case RSA_SSLV23_PADDING:
471 r=RSA_padding_check_SSLv23(to,num,buf,j,num);
474 r=RSA_padding_check_none(to,num,buf,j,num);
477 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
481 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_PADDING_CHECK_FAILED);
484 if (ctx != NULL) BN_CTX_free(ctx);
488 BN_BLINDING_free(blinding);
491 OPENSSL_cleanse(buf,num);
497 /* signature verification */
498 static int RSA_eay_public_decrypt(int flen, const unsigned char *from,
499 unsigned char *to, RSA *rsa, int padding)
504 unsigned char *buf=NULL;
510 if (ctx == NULL) goto err;
512 num=BN_num_bytes(rsa->n);
513 buf=(unsigned char *)OPENSSL_malloc(num);
516 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,ERR_R_MALLOC_FAILURE);
520 /* This check was for equality but PGP does evil things
521 * and chops off the top '0' bytes */
524 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_DATA_GREATER_THAN_MOD_LEN);
528 if (BN_bin2bn(from,flen,&f) == NULL) goto err;
530 if (BN_ucmp(&f, rsa->n) >= 0)
532 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
537 if ((rsa->_method_mod_n == NULL) && (rsa->flags & RSA_FLAG_CACHE_PUBLIC))
539 BN_MONT_CTX* bn_mont_ctx;
540 if ((bn_mont_ctx=BN_MONT_CTX_new()) == NULL)
542 if (!BN_MONT_CTX_set(bn_mont_ctx,rsa->n,ctx))
544 BN_MONT_CTX_free(bn_mont_ctx);
547 if (rsa->_method_mod_n == NULL) /* other thread may have finished first */
549 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
550 if (rsa->_method_mod_n == NULL)
552 rsa->_method_mod_n = bn_mont_ctx;
555 CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
558 BN_MONT_CTX_free(bn_mont_ctx);
561 if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->e,rsa->n,ctx,
562 rsa->_method_mod_n)) goto err;
569 case RSA_PKCS1_PADDING:
570 r=RSA_padding_check_PKCS1_type_1(to,num,buf,i,num);
573 r=RSA_padding_check_none(to,num,buf,i,num);
576 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
580 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_PADDING_CHECK_FAILED);
583 if (ctx != NULL) BN_CTX_free(ctx);
588 OPENSSL_cleanse(buf,num);
594 static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa)
603 if ((ctx=BN_CTX_new()) == NULL) goto err;
605 if (rsa->flags & RSA_FLAG_CACHE_PRIVATE)
607 if (rsa->_method_mod_p == NULL)
609 BN_MONT_CTX* bn_mont_ctx;
610 if ((bn_mont_ctx=BN_MONT_CTX_new()) == NULL)
612 if (!BN_MONT_CTX_set(bn_mont_ctx,rsa->p,ctx))
614 BN_MONT_CTX_free(bn_mont_ctx);
617 if (rsa->_method_mod_p == NULL) /* other thread may have finished first */
619 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
620 if (rsa->_method_mod_p == NULL)
622 rsa->_method_mod_p = bn_mont_ctx;
625 CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
628 BN_MONT_CTX_free(bn_mont_ctx);
631 if (rsa->_method_mod_q == NULL)
633 BN_MONT_CTX* bn_mont_ctx;
634 if ((bn_mont_ctx=BN_MONT_CTX_new()) == NULL)
636 if (!BN_MONT_CTX_set(bn_mont_ctx,rsa->q,ctx))
638 BN_MONT_CTX_free(bn_mont_ctx);
641 if (rsa->_method_mod_q == NULL) /* other thread may have finished first */
643 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
644 if (rsa->_method_mod_q == NULL)
646 rsa->_method_mod_q = bn_mont_ctx;
649 CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
652 BN_MONT_CTX_free(bn_mont_ctx);
656 if (!BN_mod(&r1,I,rsa->q,ctx)) goto err;
657 if (!rsa->meth->bn_mod_exp(&m1,&r1,rsa->dmq1,rsa->q,ctx,
658 rsa->_method_mod_q)) goto err;
660 if (!BN_mod(&r1,I,rsa->p,ctx)) goto err;
661 if (!rsa->meth->bn_mod_exp(r0,&r1,rsa->dmp1,rsa->p,ctx,
662 rsa->_method_mod_p)) goto err;
664 if (!BN_sub(r0,r0,&m1)) goto err;
665 /* This will help stop the size of r0 increasing, which does
666 * affect the multiply if it optimised for a power of 2 size */
668 if (!BN_add(r0,r0,rsa->p)) goto err;
670 if (!BN_mul(&r1,r0,rsa->iqmp,ctx)) goto err;
671 if (!BN_mod(r0,&r1,rsa->p,ctx)) goto err;
672 /* If p < q it is occasionally possible for the correction of
673 * adding 'p' if r0 is negative above to leave the result still
674 * negative. This can break the private key operations: the following
675 * second correction should *always* correct this rare occurrence.
676 * This will *never* happen with OpenSSL generated keys because
677 * they ensure p > q [steve]
680 if (!BN_add(r0,r0,rsa->p)) goto err;
681 if (!BN_mul(&r1,r0,rsa->q,ctx)) goto err;
682 if (!BN_add(r0,&r1,&m1)) goto err;
684 if (rsa->e && rsa->n)
686 if (!rsa->meth->bn_mod_exp(&vrfy,r0,rsa->e,rsa->n,ctx,NULL)) goto err;
687 /* If 'I' was greater than (or equal to) rsa->n, the operation
688 * will be equivalent to using 'I mod n'. However, the result of
689 * the verify will *always* be less than 'n' so we don't check
690 * for absolute equality, just congruency. */
691 if (!BN_sub(&vrfy, &vrfy, I)) goto err;
692 if (!BN_mod(&vrfy, &vrfy, rsa->n, ctx)) goto err;
694 if (!BN_add(&vrfy, &vrfy, rsa->n)) goto err;
695 if (!BN_is_zero(&vrfy))
696 /* 'I' and 'vrfy' aren't congruent mod n. Don't leak
697 * miscalculated CRT output, just do a raw (slower)
698 * mod_exp and return that instead. */
699 if (!rsa->meth->bn_mod_exp(r0,I,rsa->d,rsa->n,ctx,NULL)) goto err;
705 BN_clear_free(&vrfy);
710 static int RSA_eay_init(RSA *rsa)
712 rsa->flags|=RSA_FLAG_CACHE_PUBLIC|RSA_FLAG_CACHE_PRIVATE;
716 static int RSA_eay_finish(RSA *rsa)
718 if (rsa->_method_mod_n != NULL)
719 BN_MONT_CTX_free(rsa->_method_mod_n);
720 if (rsa->_method_mod_p != NULL)
721 BN_MONT_CTX_free(rsa->_method_mod_p);
722 if (rsa->_method_mod_q != NULL)
723 BN_MONT_CTX_free(rsa->_method_mod_q);