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 #include <openssl/engine.h>
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 */
96 const RSA_METHOD *RSA_PKCS1_SSLeay(void)
98 return(&rsa_pkcs1_eay_meth);
101 static int RSA_eay_public_encrypt(int flen, const unsigned char *from,
102 unsigned char *to, RSA *rsa, int padding)
105 int i,j,k,num=0,r= -1;
106 unsigned char *buf=NULL;
111 if ((ctx=BN_CTX_new()) == NULL) goto err;
112 num=BN_num_bytes(rsa->n);
113 if ((buf=(unsigned char *)OPENSSL_malloc(num)) == NULL)
115 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,ERR_R_MALLOC_FAILURE);
121 case RSA_PKCS1_PADDING:
122 i=RSA_padding_add_PKCS1_type_2(buf,num,from,flen);
124 #ifndef OPENSSL_NO_SHA
125 case RSA_PKCS1_OAEP_PADDING:
126 i=RSA_padding_add_PKCS1_OAEP(buf,num,from,flen,NULL,0);
129 case RSA_SSLV23_PADDING:
130 i=RSA_padding_add_SSLv23(buf,num,from,flen);
133 i=RSA_padding_add_none(buf,num,from,flen);
136 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
139 if (i <= 0) goto err;
141 if (BN_bin2bn(buf,num,&f) == NULL) goto err;
143 if (BN_ucmp(&f, rsa->n) >= 0)
145 /* usually the padding functions would catch this */
146 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
150 if ((rsa->_method_mod_n == NULL) && (rsa->flags & RSA_FLAG_CACHE_PUBLIC))
152 BN_MONT_CTX* bn_mont_ctx;
153 if ((bn_mont_ctx=BN_MONT_CTX_new()) == NULL)
155 if (!BN_MONT_CTX_set(bn_mont_ctx,rsa->n,ctx))
157 BN_MONT_CTX_free(bn_mont_ctx);
160 if (rsa->_method_mod_n == NULL) /* other thread may have finished first */
162 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
163 if (rsa->_method_mod_n == NULL)
165 rsa->_method_mod_n = bn_mont_ctx;
168 CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
171 BN_MONT_CTX_free(bn_mont_ctx);
174 if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->e,rsa->n,ctx,
175 rsa->_method_mod_n)) goto err;
177 /* put in leading 0 bytes if the number is less than the
178 * length of the modulus */
179 j=BN_num_bytes(&ret);
180 i=BN_bn2bin(&ret,&(to[num-j]));
181 for (k=0; k<(num-i); k++)
186 if (ctx != NULL) BN_CTX_free(ctx);
191 OPENSSL_cleanse(buf,num);
198 static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
199 unsigned char *to, RSA *rsa, int padding)
202 int i,j,k,num=0,r= -1;
203 unsigned char *buf=NULL;
209 if ((ctx=BN_CTX_new()) == NULL) goto err;
210 num=BN_num_bytes(rsa->n);
211 if ((buf=(unsigned char *)OPENSSL_malloc(num)) == NULL)
213 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,ERR_R_MALLOC_FAILURE);
219 case RSA_PKCS1_PADDING:
220 i=RSA_padding_add_PKCS1_type_1(buf,num,from,flen);
223 i=RSA_padding_add_none(buf,num,from,flen);
225 case RSA_SSLV23_PADDING:
227 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
230 if (i <= 0) goto err;
232 if (BN_bin2bn(buf,num,&f) == NULL) goto err;
234 if (BN_ucmp(&f, rsa->n) >= 0)
236 /* usually the padding functions would catch this */
237 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
241 if ((rsa->flags & RSA_FLAG_BLINDING) && (rsa->blinding == NULL))
242 RSA_blinding_on(rsa,ctx);
243 if (rsa->flags & RSA_FLAG_BLINDING)
244 if (!BN_BLINDING_convert(&f,rsa->blinding,ctx)) goto err;
246 if ( (rsa->flags & RSA_FLAG_EXT_PKEY) ||
249 (rsa->dmp1 != NULL) &&
250 (rsa->dmq1 != NULL) &&
251 (rsa->iqmp != NULL)) )
252 { if (!rsa->meth->rsa_mod_exp(&ret,&f,rsa)) goto err; }
255 if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->d,rsa->n,ctx,NULL)) goto err;
258 if (rsa->flags & RSA_FLAG_BLINDING)
259 if (!BN_BLINDING_invert(&ret,rsa->blinding,ctx)) goto err;
261 /* put in leading 0 bytes if the number is less than the
262 * length of the modulus */
263 j=BN_num_bytes(&ret);
264 i=BN_bn2bin(&ret,&(to[num-j]));
265 for (k=0; k<(num-i); k++)
270 if (ctx != NULL) BN_CTX_free(ctx);
275 OPENSSL_cleanse(buf,num);
281 static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
282 unsigned char *to, RSA *rsa, int padding)
287 unsigned char *buf=NULL;
293 if (ctx == NULL) goto err;
295 num=BN_num_bytes(rsa->n);
297 if ((buf=(unsigned char *)OPENSSL_malloc(num)) == NULL)
299 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,ERR_R_MALLOC_FAILURE);
303 /* This check was for equality but PGP does evil things
304 * and chops off the top '0' bytes */
307 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_DATA_GREATER_THAN_MOD_LEN);
311 /* make data into a big number */
312 if (BN_bin2bn(from,(int)flen,&f) == NULL) goto err;
314 if (BN_ucmp(&f, rsa->n) >= 0)
316 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
320 if ((rsa->flags & RSA_FLAG_BLINDING) && (rsa->blinding == NULL))
321 RSA_blinding_on(rsa,ctx);
322 if (rsa->flags & RSA_FLAG_BLINDING)
323 if (!BN_BLINDING_convert(&f,rsa->blinding,ctx)) goto err;
326 if ( (rsa->flags & RSA_FLAG_EXT_PKEY) ||
329 (rsa->dmp1 != NULL) &&
330 (rsa->dmq1 != NULL) &&
331 (rsa->iqmp != NULL)) )
332 { if (!rsa->meth->rsa_mod_exp(&ret,&f,rsa)) goto err; }
335 if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->d,rsa->n,ctx,NULL))
339 if (rsa->flags & RSA_FLAG_BLINDING)
340 if (!BN_BLINDING_invert(&ret,rsa->blinding,ctx)) goto err;
343 j=BN_bn2bin(&ret,p); /* j is only used with no-padding mode */
347 case RSA_PKCS1_PADDING:
348 r=RSA_padding_check_PKCS1_type_2(to,num,buf,j,num);
350 #ifndef OPENSSL_NO_SHA
351 case RSA_PKCS1_OAEP_PADDING:
352 r=RSA_padding_check_PKCS1_OAEP(to,num,buf,j,num,NULL,0);
355 case RSA_SSLV23_PADDING:
356 r=RSA_padding_check_SSLv23(to,num,buf,j,num);
359 r=RSA_padding_check_none(to,num,buf,j,num);
362 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
366 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_PADDING_CHECK_FAILED);
369 if (ctx != NULL) BN_CTX_free(ctx);
374 OPENSSL_cleanse(buf,num);
380 /* signature verification */
381 static int RSA_eay_public_decrypt(int flen, const unsigned char *from,
382 unsigned char *to, RSA *rsa, int padding)
387 unsigned char *buf=NULL;
393 if (ctx == NULL) goto err;
395 num=BN_num_bytes(rsa->n);
396 buf=(unsigned char *)OPENSSL_malloc(num);
399 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,ERR_R_MALLOC_FAILURE);
403 /* This check was for equality but PGP does evil things
404 * and chops off the top '0' bytes */
407 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_DATA_GREATER_THAN_MOD_LEN);
411 if (BN_bin2bn(from,flen,&f) == NULL) goto err;
413 if (BN_ucmp(&f, rsa->n) >= 0)
415 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
420 if ((rsa->_method_mod_n == NULL) && (rsa->flags & RSA_FLAG_CACHE_PUBLIC))
422 BN_MONT_CTX* bn_mont_ctx;
423 if ((bn_mont_ctx=BN_MONT_CTX_new()) == NULL)
425 if (!BN_MONT_CTX_set(bn_mont_ctx,rsa->n,ctx))
427 BN_MONT_CTX_free(bn_mont_ctx);
430 if (rsa->_method_mod_n == NULL) /* other thread may have finished first */
432 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
433 if (rsa->_method_mod_n == NULL)
435 rsa->_method_mod_n = bn_mont_ctx;
438 CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
441 BN_MONT_CTX_free(bn_mont_ctx);
444 if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->e,rsa->n,ctx,
445 rsa->_method_mod_n)) goto err;
452 case RSA_PKCS1_PADDING:
453 r=RSA_padding_check_PKCS1_type_1(to,num,buf,i,num);
456 r=RSA_padding_check_none(to,num,buf,i,num);
459 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
463 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_PADDING_CHECK_FAILED);
466 if (ctx != NULL) BN_CTX_free(ctx);
471 OPENSSL_cleanse(buf,num);
477 static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa)
486 if ((ctx=BN_CTX_new()) == NULL) goto err;
488 if (rsa->flags & RSA_FLAG_CACHE_PRIVATE)
490 if (rsa->_method_mod_p == NULL)
492 BN_MONT_CTX* bn_mont_ctx;
493 if ((bn_mont_ctx=BN_MONT_CTX_new()) == NULL)
495 if (!BN_MONT_CTX_set(bn_mont_ctx,rsa->p,ctx))
497 BN_MONT_CTX_free(bn_mont_ctx);
500 if (rsa->_method_mod_p == NULL) /* other thread may have finished first */
502 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
503 if (rsa->_method_mod_p == NULL)
505 rsa->_method_mod_p = bn_mont_ctx;
508 CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
511 BN_MONT_CTX_free(bn_mont_ctx);
514 if (rsa->_method_mod_q == NULL)
516 BN_MONT_CTX* bn_mont_ctx;
517 if ((bn_mont_ctx=BN_MONT_CTX_new()) == NULL)
519 if (!BN_MONT_CTX_set(bn_mont_ctx,rsa->q,ctx))
521 BN_MONT_CTX_free(bn_mont_ctx);
524 if (rsa->_method_mod_q == NULL) /* other thread may have finished first */
526 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
527 if (rsa->_method_mod_q == NULL)
529 rsa->_method_mod_q = bn_mont_ctx;
532 CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
535 BN_MONT_CTX_free(bn_mont_ctx);
539 if (!BN_mod(&r1,I,rsa->q,ctx)) goto err;
540 if (!rsa->meth->bn_mod_exp(&m1,&r1,rsa->dmq1,rsa->q,ctx,
541 rsa->_method_mod_q)) goto err;
543 if (!BN_mod(&r1,I,rsa->p,ctx)) goto err;
544 if (!rsa->meth->bn_mod_exp(r0,&r1,rsa->dmp1,rsa->p,ctx,
545 rsa->_method_mod_p)) goto err;
547 if (!BN_sub(r0,r0,&m1)) goto err;
548 /* This will help stop the size of r0 increasing, which does
549 * affect the multiply if it optimised for a power of 2 size */
551 if (!BN_add(r0,r0,rsa->p)) goto err;
553 if (!BN_mul(&r1,r0,rsa->iqmp,ctx)) goto err;
554 if (!BN_mod(r0,&r1,rsa->p,ctx)) goto err;
555 /* If p < q it is occasionally possible for the correction of
556 * adding 'p' if r0 is negative above to leave the result still
557 * negative. This can break the private key operations: the following
558 * second correction should *always* correct this rare occurrence.
559 * This will *never* happen with OpenSSL generated keys because
560 * they ensure p > q [steve]
563 if (!BN_add(r0,r0,rsa->p)) goto err;
564 if (!BN_mul(&r1,r0,rsa->q,ctx)) goto err;
565 if (!BN_add(r0,&r1,&m1)) goto err;
567 if (rsa->e && rsa->n)
569 if (!rsa->meth->bn_mod_exp(&vrfy,r0,rsa->e,rsa->n,ctx,NULL)) goto err;
570 /* If 'I' was greater than (or equal to) rsa->n, the operation
571 * will be equivalent to using 'I mod n'. However, the result of
572 * the verify will *always* be less than 'n' so we don't check
573 * for absolute equality, just congruency. */
574 if (!BN_sub(&vrfy, &vrfy, I)) goto err;
575 if (!BN_mod(&vrfy, &vrfy, rsa->n, ctx)) goto err;
576 if (BN_get_sign(&vrfy))
577 if (!BN_add(&vrfy, &vrfy, rsa->n)) goto err;
578 if (!BN_is_zero(&vrfy))
579 /* 'I' and 'vrfy' aren't congruent mod n. Don't leak
580 * miscalculated CRT output, just do a raw (slower)
581 * mod_exp and return that instead. */
582 if (!rsa->meth->bn_mod_exp(r0,I,rsa->d,rsa->n,ctx,NULL)) goto err;
588 BN_clear_free(&vrfy);
593 static int RSA_eay_init(RSA *rsa)
595 rsa->flags|=RSA_FLAG_CACHE_PUBLIC|RSA_FLAG_CACHE_PRIVATE;
599 static int RSA_eay_finish(RSA *rsa)
601 if (rsa->_method_mod_n != NULL)
602 BN_MONT_CTX_free(rsa->_method_mod_n);
603 if (rsa->_method_mod_p != NULL)
604 BN_MONT_CTX_free(rsa->_method_mod_p);
605 if (rsa->_method_mod_q != NULL)
606 BN_MONT_CTX_free(rsa->_method_mod_q);