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>
64 #ifndef OPENSSL_NO_ENGINE
65 #include <openssl/engine.h>
70 static int RSA_eay_public_encrypt(int flen, const unsigned char *from,
71 unsigned char *to, RSA *rsa,int padding);
72 static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
73 unsigned char *to, RSA *rsa,int padding);
74 static int RSA_eay_public_decrypt(int flen, const unsigned char *from,
75 unsigned char *to, RSA *rsa,int padding);
76 static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
77 unsigned char *to, RSA *rsa,int padding);
78 static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *i, RSA *rsa);
79 static int RSA_eay_init(RSA *rsa);
80 static int RSA_eay_finish(RSA *rsa);
81 static RSA_METHOD rsa_pkcs1_eay_meth={
82 "Eric Young's PKCS#1 RSA",
83 RSA_eay_public_encrypt,
84 RSA_eay_public_decrypt, /* signature verification */
85 RSA_eay_private_encrypt, /* signing */
86 RSA_eay_private_decrypt,
88 BN_mod_exp_mont, /* XXX probably we should not use Montgomery if e == 3 */
98 const RSA_METHOD *RSA_PKCS1_SSLeay(void)
100 return(&rsa_pkcs1_eay_meth);
103 static int RSA_eay_public_encrypt(int flen, const unsigned char *from,
104 unsigned char *to, RSA *rsa, int padding)
107 int i,j,k,num=0,r= -1;
108 unsigned char *buf=NULL;
113 if ((ctx=BN_CTX_new()) == NULL) goto err;
114 num=BN_num_bytes(rsa->n);
115 if ((buf=(unsigned char *)OPENSSL_malloc(num)) == NULL)
117 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,ERR_R_MALLOC_FAILURE);
123 case RSA_PKCS1_PADDING:
124 i=RSA_padding_add_PKCS1_type_2(buf,num,from,flen);
126 #ifndef OPENSSL_NO_SHA
127 case RSA_PKCS1_OAEP_PADDING:
128 i=RSA_padding_add_PKCS1_OAEP(buf,num,from,flen,NULL,0);
131 case RSA_SSLV23_PADDING:
132 i=RSA_padding_add_SSLv23(buf,num,from,flen);
135 i=RSA_padding_add_none(buf,num,from,flen);
138 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
141 if (i <= 0) goto err;
143 if (BN_bin2bn(buf,num,&f) == NULL) goto err;
145 if (BN_ucmp(&f, rsa->n) >= 0)
147 /* usually the padding functions would catch this */
148 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
152 if ((rsa->_method_mod_n == NULL) && (rsa->flags & RSA_FLAG_CACHE_PUBLIC))
154 BN_MONT_CTX* bn_mont_ctx;
155 if ((bn_mont_ctx=BN_MONT_CTX_new()) == NULL)
157 if (!BN_MONT_CTX_set(bn_mont_ctx,rsa->n,ctx))
159 BN_MONT_CTX_free(bn_mont_ctx);
162 if (rsa->_method_mod_n == NULL) /* other thread may have finished first */
164 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
165 if (rsa->_method_mod_n == NULL)
167 rsa->_method_mod_n = bn_mont_ctx;
170 CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
173 BN_MONT_CTX_free(bn_mont_ctx);
176 if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->e,rsa->n,ctx,
177 rsa->_method_mod_n)) goto err;
179 /* put in leading 0 bytes if the number is less than the
180 * length of the modulus */
181 j=BN_num_bytes(&ret);
182 i=BN_bn2bin(&ret,&(to[num-j]));
183 for (k=0; k<(num-i); k++)
188 if (ctx != NULL) BN_CTX_free(ctx);
193 OPENSSL_cleanse(buf,num);
200 static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
201 unsigned char *to, RSA *rsa, int padding)
204 int i,j,k,num=0,r= -1;
205 unsigned char *buf=NULL;
211 if ((ctx=BN_CTX_new()) == NULL) goto err;
212 num=BN_num_bytes(rsa->n);
213 if ((buf=(unsigned char *)OPENSSL_malloc(num)) == NULL)
215 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,ERR_R_MALLOC_FAILURE);
221 case RSA_PKCS1_PADDING:
222 i=RSA_padding_add_PKCS1_type_1(buf,num,from,flen);
225 i=RSA_padding_add_none(buf,num,from,flen);
227 case RSA_SSLV23_PADDING:
229 RSAerr(RSA_F_RSA_EAY_PRIVATE_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_PRIVATE_ENCRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
243 if ((rsa->flags & RSA_FLAG_BLINDING) && (rsa->blinding == NULL))
244 RSA_blinding_on(rsa,ctx);
245 if (rsa->flags & RSA_FLAG_BLINDING)
246 if (!BN_BLINDING_convert(&f,rsa->blinding,ctx)) goto err;
248 if ( (rsa->flags & RSA_FLAG_EXT_PKEY) ||
251 (rsa->dmp1 != NULL) &&
252 (rsa->dmq1 != NULL) &&
253 (rsa->iqmp != NULL)) )
254 { if (!rsa->meth->rsa_mod_exp(&ret,&f,rsa)) goto err; }
257 if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->d,rsa->n,ctx,NULL)) goto err;
260 if (rsa->flags & RSA_FLAG_BLINDING)
261 if (!BN_BLINDING_invert(&ret,rsa->blinding,ctx)) goto err;
263 /* put in leading 0 bytes if the number is less than the
264 * length of the modulus */
265 j=BN_num_bytes(&ret);
266 i=BN_bn2bin(&ret,&(to[num-j]));
267 for (k=0; k<(num-i); k++)
272 if (ctx != NULL) BN_CTX_free(ctx);
277 OPENSSL_cleanse(buf,num);
283 static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
284 unsigned char *to, RSA *rsa, int padding)
289 unsigned char *buf=NULL;
295 if (ctx == NULL) goto err;
297 num=BN_num_bytes(rsa->n);
299 if ((buf=(unsigned char *)OPENSSL_malloc(num)) == NULL)
301 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,ERR_R_MALLOC_FAILURE);
305 /* This check was for equality but PGP does evil things
306 * and chops off the top '0' bytes */
309 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_DATA_GREATER_THAN_MOD_LEN);
313 /* make data into a big number */
314 if (BN_bin2bn(from,(int)flen,&f) == NULL) goto err;
316 if (BN_ucmp(&f, rsa->n) >= 0)
318 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
322 if ((rsa->flags & RSA_FLAG_BLINDING) && (rsa->blinding == NULL))
323 RSA_blinding_on(rsa,ctx);
324 if (rsa->flags & RSA_FLAG_BLINDING)
325 if (!BN_BLINDING_convert(&f,rsa->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))
341 if (rsa->flags & RSA_FLAG_BLINDING)
342 if (!BN_BLINDING_invert(&ret,rsa->blinding,ctx)) goto err;
345 j=BN_bn2bin(&ret,p); /* j is only used with no-padding mode */
349 case RSA_PKCS1_PADDING:
350 r=RSA_padding_check_PKCS1_type_2(to,num,buf,j,num);
352 #ifndef OPENSSL_NO_SHA
353 case RSA_PKCS1_OAEP_PADDING:
354 r=RSA_padding_check_PKCS1_OAEP(to,num,buf,j,num,NULL,0);
357 case RSA_SSLV23_PADDING:
358 r=RSA_padding_check_SSLv23(to,num,buf,j,num);
361 r=RSA_padding_check_none(to,num,buf,j,num);
364 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
368 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_PADDING_CHECK_FAILED);
371 if (ctx != NULL) BN_CTX_free(ctx);
376 OPENSSL_cleanse(buf,num);
382 /* signature verification */
383 static int RSA_eay_public_decrypt(int flen, const unsigned char *from,
384 unsigned char *to, RSA *rsa, int padding)
389 unsigned char *buf=NULL;
395 if (ctx == NULL) goto err;
397 num=BN_num_bytes(rsa->n);
398 buf=(unsigned char *)OPENSSL_malloc(num);
401 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,ERR_R_MALLOC_FAILURE);
405 /* This check was for equality but PGP does evil things
406 * and chops off the top '0' bytes */
409 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_DATA_GREATER_THAN_MOD_LEN);
413 if (BN_bin2bn(from,flen,&f) == NULL) goto err;
415 if (BN_ucmp(&f, rsa->n) >= 0)
417 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
422 if ((rsa->_method_mod_n == NULL) && (rsa->flags & RSA_FLAG_CACHE_PUBLIC))
424 BN_MONT_CTX* bn_mont_ctx;
425 if ((bn_mont_ctx=BN_MONT_CTX_new()) == NULL)
427 if (!BN_MONT_CTX_set(bn_mont_ctx,rsa->n,ctx))
429 BN_MONT_CTX_free(bn_mont_ctx);
432 if (rsa->_method_mod_n == NULL) /* other thread may have finished first */
434 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
435 if (rsa->_method_mod_n == NULL)
437 rsa->_method_mod_n = bn_mont_ctx;
440 CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
443 BN_MONT_CTX_free(bn_mont_ctx);
446 if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->e,rsa->n,ctx,
447 rsa->_method_mod_n)) goto err;
454 case RSA_PKCS1_PADDING:
455 r=RSA_padding_check_PKCS1_type_1(to,num,buf,i,num);
458 r=RSA_padding_check_none(to,num,buf,i,num);
461 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
465 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_PADDING_CHECK_FAILED);
468 if (ctx != NULL) BN_CTX_free(ctx);
473 OPENSSL_cleanse(buf,num);
479 static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa)
488 if ((ctx=BN_CTX_new()) == NULL) goto err;
490 if (rsa->flags & RSA_FLAG_CACHE_PRIVATE)
492 if (rsa->_method_mod_p == NULL)
494 BN_MONT_CTX* bn_mont_ctx;
495 if ((bn_mont_ctx=BN_MONT_CTX_new()) == NULL)
497 if (!BN_MONT_CTX_set(bn_mont_ctx,rsa->p,ctx))
499 BN_MONT_CTX_free(bn_mont_ctx);
502 if (rsa->_method_mod_p == NULL) /* other thread may have finished first */
504 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
505 if (rsa->_method_mod_p == NULL)
507 rsa->_method_mod_p = bn_mont_ctx;
510 CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
513 BN_MONT_CTX_free(bn_mont_ctx);
516 if (rsa->_method_mod_q == NULL)
518 BN_MONT_CTX* bn_mont_ctx;
519 if ((bn_mont_ctx=BN_MONT_CTX_new()) == NULL)
521 if (!BN_MONT_CTX_set(bn_mont_ctx,rsa->q,ctx))
523 BN_MONT_CTX_free(bn_mont_ctx);
526 if (rsa->_method_mod_q == NULL) /* other thread may have finished first */
528 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
529 if (rsa->_method_mod_q == NULL)
531 rsa->_method_mod_q = bn_mont_ctx;
534 CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
537 BN_MONT_CTX_free(bn_mont_ctx);
541 if (!BN_mod(&r1,I,rsa->q,ctx)) goto err;
542 if (!rsa->meth->bn_mod_exp(&m1,&r1,rsa->dmq1,rsa->q,ctx,
543 rsa->_method_mod_q)) goto err;
545 if (!BN_mod(&r1,I,rsa->p,ctx)) goto err;
546 if (!rsa->meth->bn_mod_exp(r0,&r1,rsa->dmp1,rsa->p,ctx,
547 rsa->_method_mod_p)) goto err;
549 if (!BN_sub(r0,r0,&m1)) goto err;
550 /* This will help stop the size of r0 increasing, which does
551 * affect the multiply if it optimised for a power of 2 size */
553 if (!BN_add(r0,r0,rsa->p)) goto err;
555 if (!BN_mul(&r1,r0,rsa->iqmp,ctx)) goto err;
556 if (!BN_mod(r0,&r1,rsa->p,ctx)) goto err;
557 /* If p < q it is occasionally possible for the correction of
558 * adding 'p' if r0 is negative above to leave the result still
559 * negative. This can break the private key operations: the following
560 * second correction should *always* correct this rare occurrence.
561 * This will *never* happen with OpenSSL generated keys because
562 * they ensure p > q [steve]
565 if (!BN_add(r0,r0,rsa->p)) goto err;
566 if (!BN_mul(&r1,r0,rsa->q,ctx)) goto err;
567 if (!BN_add(r0,&r1,&m1)) goto err;
569 if (rsa->e && rsa->n)
571 if (!rsa->meth->bn_mod_exp(&vrfy,r0,rsa->e,rsa->n,ctx,NULL)) goto err;
572 /* If 'I' was greater than (or equal to) rsa->n, the operation
573 * will be equivalent to using 'I mod n'. However, the result of
574 * the verify will *always* be less than 'n' so we don't check
575 * for absolute equality, just congruency. */
576 if (!BN_sub(&vrfy, &vrfy, I)) goto err;
577 if (!BN_mod(&vrfy, &vrfy, rsa->n, ctx)) goto err;
578 if (BN_get_sign(&vrfy))
579 if (!BN_add(&vrfy, &vrfy, rsa->n)) goto err;
580 if (!BN_is_zero(&vrfy))
581 /* 'I' and 'vrfy' aren't congruent mod n. Don't leak
582 * miscalculated CRT output, just do a raw (slower)
583 * mod_exp and return that instead. */
584 if (!rsa->meth->bn_mod_exp(r0,I,rsa->d,rsa->n,ctx,NULL)) goto err;
590 BN_clear_free(&vrfy);
595 static int RSA_eay_init(RSA *rsa)
597 rsa->flags|=RSA_FLAG_CACHE_PUBLIC|RSA_FLAG_CACHE_PRIVATE;
601 static int RSA_eay_finish(RSA *rsa)
603 if (rsa->_method_mod_n != NULL)
604 BN_MONT_CTX_free(rsa->_method_mod_n);
605 if (rsa->_method_mod_p != NULL)
606 BN_MONT_CTX_free(rsa->_method_mod_p);
607 if (rsa->_method_mod_q != NULL)
608 BN_MONT_CTX_free(rsa->_method_mod_q);