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>
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, BN_CTX *ctx);
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 */
95 const RSA_METHOD *RSA_PKCS1_SSLeay(void)
97 return(&rsa_pkcs1_eay_meth);
101 * MONT_HELPER(rsa, bn_ctx, p, rsa->flags & RSA_FLAG_CACHE_PRIVATE, goto err);
103 #define MONT_HELPER(rsa, ctx, m, pre_cond, err_instr) \
104 if((pre_cond) && ((rsa)->_method_mod_##m == NULL) && \
105 !BN_MONT_CTX_set_locked(&((rsa)->_method_mod_##m), \
110 static int RSA_eay_public_encrypt(int flen, const unsigned char *from,
111 unsigned char *to, RSA *rsa, int padding)
114 int i,j,k,num=0,r= -1;
115 unsigned char *buf=NULL;
118 if ((ctx=BN_CTX_new()) == NULL) goto err;
121 ret = BN_CTX_get(ctx);
122 num=BN_num_bytes(rsa->n);
123 buf = OPENSSL_malloc(num);
124 if (!f || !ret || !buf)
126 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,ERR_R_MALLOC_FAILURE);
132 case RSA_PKCS1_PADDING:
133 i=RSA_padding_add_PKCS1_type_2(buf,num,from,flen);
135 #ifndef OPENSSL_NO_SHA
136 case RSA_PKCS1_OAEP_PADDING:
137 i=RSA_padding_add_PKCS1_OAEP(buf,num,from,flen,NULL,0);
140 case RSA_SSLV23_PADDING:
141 i=RSA_padding_add_SSLv23(buf,num,from,flen);
144 i=RSA_padding_add_none(buf,num,from,flen);
147 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
150 if (i <= 0) goto err;
152 if (BN_bin2bn(buf,num,f) == NULL) goto err;
154 if (BN_ucmp(f, rsa->n) >= 0)
156 /* usually the padding functions would catch this */
157 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
161 MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
163 if (!rsa->meth->bn_mod_exp(ret,f,rsa->e,rsa->n,ctx,
164 rsa->_method_mod_n)) goto err;
166 /* put in leading 0 bytes if the number is less than the
167 * length of the modulus */
169 i=BN_bn2bin(ret,&(to[num-j]));
170 for (k=0; k<(num-i); k++)
182 OPENSSL_cleanse(buf,num);
188 static BN_BLINDING *rsa_get_blinding(RSA *rsa, BIGNUM **r, int *local, BN_CTX *ctx)
192 if (rsa->blinding == NULL)
194 if (rsa->blinding == NULL)
196 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
197 if (rsa->blinding == NULL)
198 rsa->blinding = RSA_setup_blinding(rsa, ctx);
199 CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
207 if (BN_BLINDING_get_thread_id(ret) != CRYPTO_thread_id())
210 if (rsa->mt_blinding == NULL)
212 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
213 if (rsa->mt_blinding == NULL)
214 rsa->mt_blinding = RSA_setup_blinding(rsa, ctx);
215 CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
217 ret = rsa->mt_blinding;
225 static int rsa_blinding_convert(BN_BLINDING *b, int local, BIGNUM *f,
226 BIGNUM *r, BN_CTX *ctx)
229 return BN_BLINDING_convert_ex(f, NULL, b, ctx);
233 CRYPTO_w_lock(CRYPTO_LOCK_RSA_BLINDING);
234 ret = BN_BLINDING_convert_ex(f, r, b, ctx);
235 CRYPTO_w_unlock(CRYPTO_LOCK_RSA_BLINDING);
240 static int rsa_blinding_invert(BN_BLINDING *b, int local, BIGNUM *f,
241 BIGNUM *r, BN_CTX *ctx)
244 return BN_BLINDING_invert_ex(f, NULL, b, ctx);
248 CRYPTO_r_lock(CRYPTO_LOCK_RSA_BLINDING);
249 ret = BN_BLINDING_invert_ex(f, r, b, ctx);
250 CRYPTO_r_unlock(CRYPTO_LOCK_RSA_BLINDING);
256 static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
257 unsigned char *to, RSA *rsa, int padding)
259 BIGNUM *f, *ret, *br;
260 int i,j,k,num=0,r= -1;
261 unsigned char *buf=NULL;
263 int local_blinding = 0;
264 BN_BLINDING *blinding = NULL;
266 if ((ctx=BN_CTX_new()) == NULL) goto err;
269 br = BN_CTX_get(ctx);
270 ret = BN_CTX_get(ctx);
271 num = BN_num_bytes(rsa->n);
272 buf = OPENSSL_malloc(num);
273 if(!f || !ret || !buf)
275 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,ERR_R_MALLOC_FAILURE);
281 case RSA_PKCS1_PADDING:
282 i=RSA_padding_add_PKCS1_type_1(buf,num,from,flen);
285 i=RSA_padding_add_none(buf,num,from,flen);
287 case RSA_SSLV23_PADDING:
289 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
292 if (i <= 0) goto err;
294 if (BN_bin2bn(buf,num,f) == NULL) goto err;
296 if (BN_ucmp(f, rsa->n) >= 0)
298 /* usually the padding functions would catch this */
299 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
303 if (!(rsa->flags & RSA_FLAG_NO_BLINDING))
305 blinding = rsa_get_blinding(rsa, &br, &local_blinding, ctx);
306 if (blinding == NULL)
308 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT, ERR_R_INTERNAL_ERROR);
313 if (blinding != NULL)
314 if (!rsa_blinding_convert(blinding, local_blinding, f, br, ctx))
317 if ( (rsa->flags & RSA_FLAG_EXT_PKEY) ||
320 (rsa->dmp1 != NULL) &&
321 (rsa->dmq1 != NULL) &&
322 (rsa->iqmp != NULL)) )
323 { if (!rsa->meth->rsa_mod_exp(ret,f,rsa,ctx)) goto err; }
326 MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
327 if (!rsa->meth->bn_mod_exp(ret,f,rsa->d,rsa->n,ctx,
328 rsa->_method_mod_n)) goto err;
332 if (!rsa_blinding_invert(blinding, local_blinding, ret, br, ctx))
335 /* put in leading 0 bytes if the number is less than the
336 * length of the modulus */
338 i=BN_bn2bin(ret,&(to[num-j]));
339 for (k=0; k<(num-i); k++)
351 OPENSSL_cleanse(buf,num);
357 static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
358 unsigned char *to, RSA *rsa, int padding)
360 BIGNUM *f, *ret, *br;
363 unsigned char *buf=NULL;
365 int local_blinding = 0;
366 BN_BLINDING *blinding = NULL;
368 if((ctx = BN_CTX_new()) == NULL) goto err;
371 br = BN_CTX_get(ctx);
372 ret = BN_CTX_get(ctx);
373 num = BN_num_bytes(rsa->n);
374 buf = OPENSSL_malloc(num);
375 if(!f || !ret || !buf)
377 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,ERR_R_MALLOC_FAILURE);
381 /* This check was for equality but PGP does evil things
382 * and chops off the top '0' bytes */
385 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_DATA_GREATER_THAN_MOD_LEN);
389 /* make data into a big number */
390 if (BN_bin2bn(from,(int)flen,f) == NULL) goto err;
392 if (BN_ucmp(f, rsa->n) >= 0)
394 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
398 if (!(rsa->flags & RSA_FLAG_NO_BLINDING))
400 blinding = rsa_get_blinding(rsa, &br, &local_blinding, ctx);
401 if (blinding == NULL)
403 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT, ERR_R_INTERNAL_ERROR);
408 if (blinding != NULL)
409 if (!rsa_blinding_convert(blinding, local_blinding, f, br, ctx))
413 if ( (rsa->flags & RSA_FLAG_EXT_PKEY) ||
416 (rsa->dmp1 != NULL) &&
417 (rsa->dmq1 != NULL) &&
418 (rsa->iqmp != NULL)) )
419 { if (!rsa->meth->rsa_mod_exp(ret,f,rsa,ctx)) goto err; }
422 MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
423 if (!rsa->meth->bn_mod_exp(ret,f,rsa->d,rsa->n,ctx,
429 if (!rsa_blinding_invert(blinding, local_blinding, ret, br, ctx))
433 j=BN_bn2bin(ret,p); /* j is only used with no-padding mode */
437 case RSA_PKCS1_PADDING:
438 r=RSA_padding_check_PKCS1_type_2(to,num,buf,j,num);
440 #ifndef OPENSSL_NO_SHA
441 case RSA_PKCS1_OAEP_PADDING:
442 r=RSA_padding_check_PKCS1_OAEP(to,num,buf,j,num,NULL,0);
445 case RSA_SSLV23_PADDING:
446 r=RSA_padding_check_SSLv23(to,num,buf,j,num);
449 r=RSA_padding_check_none(to,num,buf,j,num);
452 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
456 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_PADDING_CHECK_FAILED);
466 OPENSSL_cleanse(buf,num);
472 /* signature verification */
473 static int RSA_eay_public_decrypt(int flen, const unsigned char *from,
474 unsigned char *to, RSA *rsa, int padding)
479 unsigned char *buf=NULL;
482 if((ctx = BN_CTX_new()) == NULL) goto err;
485 ret = BN_CTX_get(ctx);
486 num=BN_num_bytes(rsa->n);
487 buf = OPENSSL_malloc(num);
488 if(!f || !ret || !buf)
490 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,ERR_R_MALLOC_FAILURE);
494 /* This check was for equality but PGP does evil things
495 * and chops off the top '0' bytes */
498 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_DATA_GREATER_THAN_MOD_LEN);
502 if (BN_bin2bn(from,flen,f) == NULL) goto err;
504 if (BN_ucmp(f, rsa->n) >= 0)
506 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
510 MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
512 if (!rsa->meth->bn_mod_exp(ret,f,rsa->e,rsa->n,ctx,
513 rsa->_method_mod_n)) goto err;
520 case RSA_PKCS1_PADDING:
521 r=RSA_padding_check_PKCS1_type_1(to,num,buf,i,num);
524 r=RSA_padding_check_none(to,num,buf,i,num);
527 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
531 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_PADDING_CHECK_FAILED);
541 OPENSSL_cleanse(buf,num);
547 static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa, BN_CTX *ctx)
549 BIGNUM *r1,*m1,*vrfy;
553 r1 = BN_CTX_get(ctx);
554 m1 = BN_CTX_get(ctx);
555 vrfy = BN_CTX_get(ctx);
557 MONT_HELPER(rsa, ctx, p, rsa->flags & RSA_FLAG_CACHE_PRIVATE, goto err);
558 MONT_HELPER(rsa, ctx, q, rsa->flags & RSA_FLAG_CACHE_PRIVATE, goto err);
559 MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
561 if (!BN_mod(r1,I,rsa->q,ctx)) goto err;
562 if (!rsa->meth->bn_mod_exp(m1,r1,rsa->dmq1,rsa->q,ctx,
563 rsa->_method_mod_q)) goto err;
565 if (!BN_mod(r1,I,rsa->p,ctx)) goto err;
566 if (!rsa->meth->bn_mod_exp(r0,r1,rsa->dmp1,rsa->p,ctx,
567 rsa->_method_mod_p)) goto err;
569 if (!BN_sub(r0,r0,m1)) goto err;
570 /* This will help stop the size of r0 increasing, which does
571 * affect the multiply if it optimised for a power of 2 size */
572 if (BN_is_negative(r0))
573 if (!BN_add(r0,r0,rsa->p)) goto err;
575 if (!BN_mul(r1,r0,rsa->iqmp,ctx)) goto err;
576 if (!BN_mod(r0,r1,rsa->p,ctx)) goto err;
577 /* If p < q it is occasionally possible for the correction of
578 * adding 'p' if r0 is negative above to leave the result still
579 * negative. This can break the private key operations: the following
580 * second correction should *always* correct this rare occurrence.
581 * This will *never* happen with OpenSSL generated keys because
582 * they ensure p > q [steve]
584 if (BN_is_negative(r0))
585 if (!BN_add(r0,r0,rsa->p)) goto err;
586 if (!BN_mul(r1,r0,rsa->q,ctx)) goto err;
587 if (!BN_add(r0,r1,m1)) goto err;
589 if (rsa->e && rsa->n)
591 if (!rsa->meth->bn_mod_exp(vrfy,r0,rsa->e,rsa->n,ctx,rsa->_method_mod_n)) goto err;
592 /* If 'I' was greater than (or equal to) rsa->n, the operation
593 * will be equivalent to using 'I mod n'. However, the result of
594 * the verify will *always* be less than 'n' so we don't check
595 * for absolute equality, just congruency. */
596 if (!BN_sub(vrfy, vrfy, I)) goto err;
597 if (!BN_mod(vrfy, vrfy, rsa->n, ctx)) goto err;
598 if (BN_is_negative(vrfy))
599 if (!BN_add(vrfy, vrfy, rsa->n)) goto err;
600 if (!BN_is_zero(vrfy))
601 /* 'I' and 'vrfy' aren't congruent mod n. Don't leak
602 * miscalculated CRT output, just do a raw (slower)
603 * mod_exp and return that instead. */
604 if (!rsa->meth->bn_mod_exp(r0,I,rsa->d,rsa->n,ctx,
605 rsa->_method_mod_n)) goto err;
613 static int RSA_eay_init(RSA *rsa)
615 rsa->flags|=RSA_FLAG_CACHE_PUBLIC|RSA_FLAG_CACHE_PRIVATE;
619 static int RSA_eay_finish(RSA *rsa)
621 if (rsa->_method_mod_n != NULL)
622 BN_MONT_CTX_free(rsa->_method_mod_n);
623 if (rsa->_method_mod_p != NULL)
624 BN_MONT_CTX_free(rsa->_method_mod_p);
625 if (rsa->_method_mod_q != NULL)
626 BN_MONT_CTX_free(rsa->_method_mod_q);