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.]
62 #include <openssl/bn.h>
63 #include <openssl/rsa.h>
64 #include <openssl/rand.h>
66 #if !defined(RSA_NULL) && !defined(OPENSSL_FIPS)
68 static int RSA_eay_public_encrypt(int flen, const unsigned char *from,
69 unsigned char *to, RSA *rsa,int padding);
70 static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
71 unsigned char *to, RSA *rsa,int padding);
72 static int RSA_eay_public_decrypt(int flen, const unsigned char *from,
73 unsigned char *to, RSA *rsa,int padding);
74 static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
75 unsigned char *to, RSA *rsa,int padding);
76 static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *i, RSA *rsa);
77 static int RSA_eay_init(RSA *rsa);
78 static int RSA_eay_finish(RSA *rsa);
79 static RSA_METHOD rsa_pkcs1_eay_meth={
80 "Eric Young's PKCS#1 RSA",
81 RSA_eay_public_encrypt,
82 RSA_eay_public_decrypt, /* signature verification */
83 RSA_eay_private_encrypt, /* signing */
84 RSA_eay_private_decrypt,
86 BN_mod_exp_mont, /* XXX probably we should not use Montgomery if e == 3 */
95 const RSA_METHOD *RSA_PKCS1_SSLeay(void)
97 return(&rsa_pkcs1_eay_meth);
100 static int RSA_eay_public_encrypt(int flen, const unsigned char *from,
101 unsigned char *to, RSA *rsa, int padding)
104 int i,j,k,num=0,r= -1;
105 unsigned char *buf=NULL;
110 if ((ctx=BN_CTX_new()) == NULL) goto err;
111 num=BN_num_bytes(rsa->n);
112 if ((buf=(unsigned char *)OPENSSL_malloc(num)) == NULL)
114 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,ERR_R_MALLOC_FAILURE);
120 case RSA_PKCS1_PADDING:
121 i=RSA_padding_add_PKCS1_type_2(buf,num,from,flen);
123 #ifndef OPENSSL_NO_SHA
124 case RSA_PKCS1_OAEP_PADDING:
125 i=RSA_padding_add_PKCS1_OAEP(buf,num,from,flen,NULL,0);
128 case RSA_SSLV23_PADDING:
129 i=RSA_padding_add_SSLv23(buf,num,from,flen);
132 i=RSA_padding_add_none(buf,num,from,flen);
135 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
138 if (i <= 0) goto err;
140 if (BN_bin2bn(buf,num,&f) == NULL) goto err;
142 if (BN_ucmp(&f, rsa->n) >= 0)
144 /* usually the padding functions would catch this */
145 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
149 if ((rsa->_method_mod_n == NULL) && (rsa->flags & RSA_FLAG_CACHE_PUBLIC))
151 BN_MONT_CTX* bn_mont_ctx;
152 if ((bn_mont_ctx=BN_MONT_CTX_new()) == NULL)
154 if (!BN_MONT_CTX_set(bn_mont_ctx,rsa->n,ctx))
156 BN_MONT_CTX_free(bn_mont_ctx);
159 if (rsa->_method_mod_n == NULL) /* other thread may have finished first */
161 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
162 if (rsa->_method_mod_n == NULL)
164 rsa->_method_mod_n = bn_mont_ctx;
167 CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
170 BN_MONT_CTX_free(bn_mont_ctx);
173 if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->e,rsa->n,ctx,
174 rsa->_method_mod_n)) goto err;
176 /* put in leading 0 bytes if the number is less than the
177 * length of the modulus */
178 j=BN_num_bytes(&ret);
179 i=BN_bn2bin(&ret,&(to[num-j]));
180 for (k=0; k<(num-i); k++)
185 if (ctx != NULL) BN_CTX_free(ctx);
190 OPENSSL_cleanse(buf,num);
196 static int rsa_eay_blinding(RSA *rsa, BN_CTX *ctx)
199 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
200 /* Check again inside the lock - the macro's check is racey */
201 if(rsa->blinding == NULL)
202 ret = RSA_blinding_on(rsa, ctx);
203 CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
207 #define BLINDING_HELPER(rsa, ctx, err_instr) \
209 if((!((rsa)->flags & RSA_FLAG_NO_BLINDING)) && \
210 ((rsa)->blinding == NULL) && \
211 !rsa_eay_blinding(rsa, ctx)) \
215 static BN_BLINDING *setup_blinding(RSA *rsa, BN_CTX *ctx)
218 BN_BLINDING *ret = NULL;
220 /* added in OpenSSL 0.9.6j and 0.9.7b */
222 /* NB: similar code appears in RSA_blinding_on (rsa_lib.c);
223 * this should be placed in a new function of its own, but for reasons
224 * of binary compatibility can't */
228 if ((RAND_status() == 0) && rsa->d != NULL && rsa->d->d != NULL)
230 /* if PRNG is not properly seeded, resort to secret exponent as unpredictable seed */
231 RAND_add(rsa->d->d, rsa->d->dmax * sizeof rsa->d->d[0], 0);
232 if (!BN_pseudo_rand_range(A,rsa->n)) goto err;
236 if (!BN_rand_range(A,rsa->n)) goto err;
238 if ((Ai=BN_mod_inverse(NULL,A,rsa->n,ctx)) == NULL) goto err;
240 if (!rsa->meth->bn_mod_exp(A,A,rsa->e,rsa->n,ctx,rsa->_method_mod_n))
242 ret = BN_BLINDING_new(A,Ai,rsa->n);
250 static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
251 unsigned char *to, RSA *rsa, int padding)
254 int i,j,k,num=0,r= -1;
255 unsigned char *buf=NULL;
257 int local_blinding = 0;
258 BN_BLINDING *blinding = NULL;
263 if ((ctx=BN_CTX_new()) == NULL) goto err;
264 num=BN_num_bytes(rsa->n);
265 if ((buf=(unsigned char *)OPENSSL_malloc(num)) == NULL)
267 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,ERR_R_MALLOC_FAILURE);
273 case RSA_PKCS1_PADDING:
274 i=RSA_padding_add_PKCS1_type_1(buf,num,from,flen);
277 i=RSA_padding_add_none(buf,num,from,flen);
279 case RSA_SSLV23_PADDING:
281 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
284 if (i <= 0) goto err;
286 if (BN_bin2bn(buf,num,&f) == NULL) goto err;
288 if (BN_ucmp(&f, rsa->n) >= 0)
290 /* usually the padding functions would catch this */
291 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
295 BLINDING_HELPER(rsa, ctx, goto err;);
296 blinding = rsa->blinding;
298 /* Now unless blinding is disabled, 'blinding' is non-NULL.
299 * But the BN_BLINDING object may be owned by some other thread
300 * (we don't want to keep it constant and we don't want to use
301 * lots of locking to avoid race conditions, so only a single
302 * thread can use it; other threads have to use local blinding
304 if (!(rsa->flags & RSA_FLAG_NO_BLINDING))
306 if (blinding == NULL)
308 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT, ERR_R_INTERNAL_ERROR);
313 if (blinding != NULL)
315 if (blinding->thread_id != CRYPTO_thread_id())
317 /* we need a local one-time blinding factor */
319 blinding = setup_blinding(rsa, ctx);
320 if (blinding == NULL)
327 if (!BN_BLINDING_convert(&f, blinding, ctx)) goto err;
329 if ( (rsa->flags & RSA_FLAG_EXT_PKEY) ||
332 (rsa->dmp1 != NULL) &&
333 (rsa->dmq1 != NULL) &&
334 (rsa->iqmp != NULL)) )
335 { if (!rsa->meth->rsa_mod_exp(&ret,&f,rsa)) goto err; }
338 if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->d,rsa->n,ctx,NULL)) goto err;
342 if (!BN_BLINDING_invert(&ret, blinding, ctx)) goto err;
344 /* put in leading 0 bytes if the number is less than the
345 * length of the modulus */
346 j=BN_num_bytes(&ret);
347 i=BN_bn2bin(&ret,&(to[num-j]));
348 for (k=0; k<(num-i); k++)
353 if (ctx != NULL) BN_CTX_free(ctx);
357 BN_BLINDING_free(blinding);
360 OPENSSL_cleanse(buf,num);
366 static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
367 unsigned char *to, RSA *rsa, int padding)
372 unsigned char *buf=NULL;
374 int local_blinding = 0;
375 BN_BLINDING *blinding = NULL;
380 if (ctx == NULL) goto err;
382 num=BN_num_bytes(rsa->n);
384 if ((buf=(unsigned char *)OPENSSL_malloc(num)) == NULL)
386 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,ERR_R_MALLOC_FAILURE);
390 /* This check was for equality but PGP does evil things
391 * and chops off the top '0' bytes */
394 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_DATA_GREATER_THAN_MOD_LEN);
398 /* make data into a big number */
399 if (BN_bin2bn(from,(int)flen,&f) == NULL) goto err;
401 if (BN_ucmp(&f, rsa->n) >= 0)
403 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
407 BLINDING_HELPER(rsa, ctx, goto err;);
408 blinding = rsa->blinding;
410 /* Now unless blinding is disabled, 'blinding' is non-NULL.
411 * But the BN_BLINDING object may be owned by some other thread
412 * (we don't want to keep it constant and we don't want to use
413 * lots of locking to avoid race conditions, so only a single
414 * thread can use it; other threads have to use local blinding
416 if (!(rsa->flags & RSA_FLAG_NO_BLINDING))
418 if (blinding == NULL)
420 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT, ERR_R_INTERNAL_ERROR);
425 if (blinding != NULL)
427 if (blinding->thread_id != CRYPTO_thread_id())
429 /* we need a local one-time blinding factor */
431 blinding = setup_blinding(rsa, ctx);
432 if (blinding == NULL)
439 if (!BN_BLINDING_convert(&f, blinding, ctx)) goto err;
442 if ( (rsa->flags & RSA_FLAG_EXT_PKEY) ||
445 (rsa->dmp1 != NULL) &&
446 (rsa->dmq1 != NULL) &&
447 (rsa->iqmp != NULL)) )
448 { if (!rsa->meth->rsa_mod_exp(&ret,&f,rsa)) goto err; }
451 if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->d,rsa->n,ctx,NULL))
456 if (!BN_BLINDING_invert(&ret, blinding, ctx)) goto err;
459 j=BN_bn2bin(&ret,p); /* j is only used with no-padding mode */
463 case RSA_PKCS1_PADDING:
464 r=RSA_padding_check_PKCS1_type_2(to,num,buf,j,num);
466 #ifndef OPENSSL_NO_SHA
467 case RSA_PKCS1_OAEP_PADDING:
468 r=RSA_padding_check_PKCS1_OAEP(to,num,buf,j,num,NULL,0);
471 case RSA_SSLV23_PADDING:
472 r=RSA_padding_check_SSLv23(to,num,buf,j,num);
475 r=RSA_padding_check_none(to,num,buf,j,num);
478 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
482 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_PADDING_CHECK_FAILED);
485 if (ctx != NULL) BN_CTX_free(ctx);
489 BN_BLINDING_free(blinding);
492 OPENSSL_cleanse(buf,num);
498 /* signature verification */
499 static int RSA_eay_public_decrypt(int flen, const unsigned char *from,
500 unsigned char *to, RSA *rsa, int padding)
505 unsigned char *buf=NULL;
511 if (ctx == NULL) goto err;
513 num=BN_num_bytes(rsa->n);
514 buf=(unsigned char *)OPENSSL_malloc(num);
517 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,ERR_R_MALLOC_FAILURE);
521 /* This check was for equality but PGP does evil things
522 * and chops off the top '0' bytes */
525 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_DATA_GREATER_THAN_MOD_LEN);
529 if (BN_bin2bn(from,flen,&f) == NULL) goto err;
531 if (BN_ucmp(&f, rsa->n) >= 0)
533 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
538 if ((rsa->_method_mod_n == NULL) && (rsa->flags & RSA_FLAG_CACHE_PUBLIC))
540 BN_MONT_CTX* bn_mont_ctx;
541 if ((bn_mont_ctx=BN_MONT_CTX_new()) == NULL)
543 if (!BN_MONT_CTX_set(bn_mont_ctx,rsa->n,ctx))
545 BN_MONT_CTX_free(bn_mont_ctx);
548 if (rsa->_method_mod_n == NULL) /* other thread may have finished first */
550 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
551 if (rsa->_method_mod_n == NULL)
553 rsa->_method_mod_n = bn_mont_ctx;
556 CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
559 BN_MONT_CTX_free(bn_mont_ctx);
562 if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->e,rsa->n,ctx,
563 rsa->_method_mod_n)) goto err;
570 case RSA_PKCS1_PADDING:
571 r=RSA_padding_check_PKCS1_type_1(to,num,buf,i,num);
574 r=RSA_padding_check_none(to,num,buf,i,num);
577 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
581 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_PADDING_CHECK_FAILED);
584 if (ctx != NULL) BN_CTX_free(ctx);
589 OPENSSL_cleanse(buf,num);
595 static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa)
604 if ((ctx=BN_CTX_new()) == NULL) goto err;
606 if (rsa->flags & RSA_FLAG_CACHE_PRIVATE)
608 if (rsa->_method_mod_p == NULL)
610 BN_MONT_CTX* bn_mont_ctx;
611 if ((bn_mont_ctx=BN_MONT_CTX_new()) == NULL)
613 if (!BN_MONT_CTX_set(bn_mont_ctx,rsa->p,ctx))
615 BN_MONT_CTX_free(bn_mont_ctx);
618 if (rsa->_method_mod_p == NULL) /* other thread may have finished first */
620 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
621 if (rsa->_method_mod_p == NULL)
623 rsa->_method_mod_p = bn_mont_ctx;
626 CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
629 BN_MONT_CTX_free(bn_mont_ctx);
632 if (rsa->_method_mod_q == NULL)
634 BN_MONT_CTX* bn_mont_ctx;
635 if ((bn_mont_ctx=BN_MONT_CTX_new()) == NULL)
637 if (!BN_MONT_CTX_set(bn_mont_ctx,rsa->q,ctx))
639 BN_MONT_CTX_free(bn_mont_ctx);
642 if (rsa->_method_mod_q == NULL) /* other thread may have finished first */
644 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
645 if (rsa->_method_mod_q == NULL)
647 rsa->_method_mod_q = bn_mont_ctx;
650 CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
653 BN_MONT_CTX_free(bn_mont_ctx);
657 if (!BN_mod(&r1,I,rsa->q,ctx)) goto err;
658 if (!rsa->meth->bn_mod_exp(&m1,&r1,rsa->dmq1,rsa->q,ctx,
659 rsa->_method_mod_q)) goto err;
661 if (!BN_mod(&r1,I,rsa->p,ctx)) goto err;
662 if (!rsa->meth->bn_mod_exp(r0,&r1,rsa->dmp1,rsa->p,ctx,
663 rsa->_method_mod_p)) goto err;
665 if (!BN_sub(r0,r0,&m1)) goto err;
666 /* This will help stop the size of r0 increasing, which does
667 * affect the multiply if it optimised for a power of 2 size */
669 if (!BN_add(r0,r0,rsa->p)) goto err;
671 if (!BN_mul(&r1,r0,rsa->iqmp,ctx)) goto err;
672 if (!BN_mod(r0,&r1,rsa->p,ctx)) goto err;
673 /* If p < q it is occasionally possible for the correction of
674 * adding 'p' if r0 is negative above to leave the result still
675 * negative. This can break the private key operations: the following
676 * second correction should *always* correct this rare occurrence.
677 * This will *never* happen with OpenSSL generated keys because
678 * they ensure p > q [steve]
681 if (!BN_add(r0,r0,rsa->p)) goto err;
682 if (!BN_mul(&r1,r0,rsa->q,ctx)) goto err;
683 if (!BN_add(r0,&r1,&m1)) goto err;
685 if (rsa->e && rsa->n)
687 if (!rsa->meth->bn_mod_exp(&vrfy,r0,rsa->e,rsa->n,ctx,NULL)) goto err;
688 /* If 'I' was greater than (or equal to) rsa->n, the operation
689 * will be equivalent to using 'I mod n'. However, the result of
690 * the verify will *always* be less than 'n' so we don't check
691 * for absolute equality, just congruency. */
692 if (!BN_sub(&vrfy, &vrfy, I)) goto err;
693 if (!BN_mod(&vrfy, &vrfy, rsa->n, ctx)) goto err;
695 if (!BN_add(&vrfy, &vrfy, rsa->n)) goto err;
696 if (!BN_is_zero(&vrfy))
697 /* 'I' and 'vrfy' aren't congruent mod n. Don't leak
698 * miscalculated CRT output, just do a raw (slower)
699 * mod_exp and return that instead. */
700 if (!rsa->meth->bn_mod_exp(r0,I,rsa->d,rsa->n,ctx,NULL)) goto err;
706 BN_clear_free(&vrfy);
711 static int RSA_eay_init(RSA *rsa)
713 rsa->flags|=RSA_FLAG_CACHE_PUBLIC|RSA_FLAG_CACHE_PRIVATE;
717 static int RSA_eay_finish(RSA *rsa)
719 if (rsa->_method_mod_n != NULL)
720 BN_MONT_CTX_free(rsa->_method_mod_n);
721 if (rsa->_method_mod_p != NULL)
722 BN_MONT_CTX_free(rsa->_method_mod_p);
723 if (rsa->_method_mod_q != NULL)
724 BN_MONT_CTX_free(rsa->_method_mod_q);