Import OpenSSL-0.9.8f.
[dragonfly.git] / crypto / openssl-0.9 / crypto / rsa / rsa_eay.c
CommitLineData
56276539
SS
1/* crypto/rsa/rsa_eay.c */
2/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3 * All rights reserved.
4 *
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.
8 *
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).
15 *
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.
22 *
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
25 * are met:
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)"
40 *
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
51 * SUCH DAMAGE.
52 *
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.]
57 */
58/* ====================================================================
74093195 59 * Copyright (c) 1998-2006 The OpenSSL Project. All rights reserved.
56276539
SS
60 *
61 * Redistribution and use in source and binary forms, with or without
62 * modification, are permitted provided that the following conditions
63 * are met:
64 *
65 * 1. Redistributions of source code must retain the above copyright
66 * notice, this list of conditions and the following disclaimer.
67 *
68 * 2. Redistributions in binary form must reproduce the above copyright
69 * notice, this list of conditions and the following disclaimer in
70 * the documentation and/or other materials provided with the
71 * distribution.
72 *
73 * 3. All advertising materials mentioning features or use of this
74 * software must display the following acknowledgment:
75 * "This product includes software developed by the OpenSSL Project
76 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
77 *
78 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
79 * endorse or promote products derived from this software without
80 * prior written permission. For written permission, please contact
81 * openssl-core@openssl.org.
82 *
83 * 5. Products derived from this software may not be called "OpenSSL"
84 * nor may "OpenSSL" appear in their names without prior written
85 * permission of the OpenSSL Project.
86 *
87 * 6. Redistributions of any form whatsoever must retain the following
88 * acknowledgment:
89 * "This product includes software developed by the OpenSSL Project
90 * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
91 *
92 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
93 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
94 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
95 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
96 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
97 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
98 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
99 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
100 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
101 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
102 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
103 * OF THE POSSIBILITY OF SUCH DAMAGE.
104 * ====================================================================
105 *
106 * This product includes cryptographic software written by Eric Young
107 * (eay@cryptsoft.com). This product includes software written by Tim
108 * Hudson (tjh@cryptsoft.com).
109 *
110 */
111
112#include <stdio.h>
113#include "cryptlib.h"
114#include <openssl/bn.h>
115#include <openssl/rsa.h>
116#include <openssl/rand.h>
117
118#ifndef RSA_NULL
119
120static int RSA_eay_public_encrypt(int flen, const unsigned char *from,
121 unsigned char *to, RSA *rsa,int padding);
122static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
123 unsigned char *to, RSA *rsa,int padding);
124static int RSA_eay_public_decrypt(int flen, const unsigned char *from,
125 unsigned char *to, RSA *rsa,int padding);
126static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
127 unsigned char *to, RSA *rsa,int padding);
128static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *i, RSA *rsa, BN_CTX *ctx);
129static int RSA_eay_init(RSA *rsa);
130static int RSA_eay_finish(RSA *rsa);
131static RSA_METHOD rsa_pkcs1_eay_meth={
132 "Eric Young's PKCS#1 RSA",
133 RSA_eay_public_encrypt,
134 RSA_eay_public_decrypt, /* signature verification */
135 RSA_eay_private_encrypt, /* signing */
136 RSA_eay_private_decrypt,
137 RSA_eay_mod_exp,
138 BN_mod_exp_mont, /* XXX probably we should not use Montgomery if e == 3 */
139 RSA_eay_init,
140 RSA_eay_finish,
141 0, /* flags */
142 NULL,
143 0, /* rsa_sign */
144 0, /* rsa_verify */
145 NULL /* rsa_keygen */
146 };
147
148const RSA_METHOD *RSA_PKCS1_SSLeay(void)
149 {
150 return(&rsa_pkcs1_eay_meth);
151 }
152
153/* Usage example;
154 * MONT_HELPER(rsa, bn_ctx, p, rsa->flags & RSA_FLAG_CACHE_PRIVATE, goto err);
155 */
156#define MONT_HELPER(rsa, ctx, m, pre_cond, err_instr) \
157 if((pre_cond) && ((rsa)->_method_mod_##m == NULL) && \
158 !BN_MONT_CTX_set_locked(&((rsa)->_method_mod_##m), \
159 CRYPTO_LOCK_RSA, \
160 (rsa)->m, (ctx))) \
161 err_instr
162
163static int RSA_eay_public_encrypt(int flen, const unsigned char *from,
164 unsigned char *to, RSA *rsa, int padding)
165 {
166 BIGNUM *f,*ret;
167 int i,j,k,num=0,r= -1;
168 unsigned char *buf=NULL;
169 BN_CTX *ctx=NULL;
170
3b25c29b
PA
171 if (BN_num_bits(rsa->n) > OPENSSL_RSA_MAX_MODULUS_BITS)
172 {
173 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT, RSA_R_MODULUS_TOO_LARGE);
174 return -1;
175 }
176
177 if (BN_ucmp(rsa->n, rsa->e) <= 0)
178 {
179 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT, RSA_R_BAD_E_VALUE);
180 return -1;
181 }
182
183 /* for large moduli, enforce exponent limit */
184 if (BN_num_bits(rsa->n) > OPENSSL_RSA_SMALL_MODULUS_BITS)
185 {
186 if (BN_num_bits(rsa->e) > OPENSSL_RSA_MAX_PUBEXP_BITS)
187 {
188 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT, RSA_R_BAD_E_VALUE);
189 return -1;
190 }
191 }
192
56276539
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193 if ((ctx=BN_CTX_new()) == NULL) goto err;
194 BN_CTX_start(ctx);
195 f = BN_CTX_get(ctx);
196 ret = BN_CTX_get(ctx);
197 num=BN_num_bytes(rsa->n);
198 buf = OPENSSL_malloc(num);
199 if (!f || !ret || !buf)
200 {
201 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,ERR_R_MALLOC_FAILURE);
202 goto err;
203 }
204
205 switch (padding)
206 {
207 case RSA_PKCS1_PADDING:
208 i=RSA_padding_add_PKCS1_type_2(buf,num,from,flen);
209 break;
210#ifndef OPENSSL_NO_SHA
211 case RSA_PKCS1_OAEP_PADDING:
212 i=RSA_padding_add_PKCS1_OAEP(buf,num,from,flen,NULL,0);
213 break;
214#endif
215 case RSA_SSLV23_PADDING:
216 i=RSA_padding_add_SSLv23(buf,num,from,flen);
217 break;
218 case RSA_NO_PADDING:
219 i=RSA_padding_add_none(buf,num,from,flen);
220 break;
221 default:
222 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
223 goto err;
224 }
225 if (i <= 0) goto err;
226
227 if (BN_bin2bn(buf,num,f) == NULL) goto err;
228
229 if (BN_ucmp(f, rsa->n) >= 0)
230 {
231 /* usually the padding functions would catch this */
232 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
233 goto err;
234 }
235
236 MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
237
238 if (!rsa->meth->bn_mod_exp(ret,f,rsa->e,rsa->n,ctx,
239 rsa->_method_mod_n)) goto err;
240
241 /* put in leading 0 bytes if the number is less than the
242 * length of the modulus */
243 j=BN_num_bytes(ret);
244 i=BN_bn2bin(ret,&(to[num-j]));
245 for (k=0; k<(num-i); k++)
246 to[k]=0;
247
248 r=num;
249err:
250 if (ctx != NULL)
251 {
252 BN_CTX_end(ctx);
253 BN_CTX_free(ctx);
254 }
255 if (buf != NULL)
256 {
257 OPENSSL_cleanse(buf,num);
258 OPENSSL_free(buf);
259 }
260 return(r);
261 }
262
74093195 263static BN_BLINDING *rsa_get_blinding(RSA *rsa, int *local, BN_CTX *ctx)
56276539
SS
264{
265 BN_BLINDING *ret;
74093195
SS
266 int got_write_lock = 0;
267
268 CRYPTO_r_lock(CRYPTO_LOCK_RSA);
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269
270 if (rsa->blinding == NULL)
271 {
74093195
SS
272 CRYPTO_r_unlock(CRYPTO_LOCK_RSA);
273 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
274 got_write_lock = 1;
275
56276539 276 if (rsa->blinding == NULL)
74093195 277 rsa->blinding = RSA_setup_blinding(rsa, ctx);
56276539
SS
278 }
279
280 ret = rsa->blinding;
281 if (ret == NULL)
74093195 282 goto err;
56276539 283
74093195
SS
284 if (BN_BLINDING_get_thread_id(ret) == CRYPTO_thread_id())
285 {
286 /* rsa->blinding is ours! */
287
288 *local = 1;
289 }
290 else
56276539 291 {
74093195
SS
292 /* resort to rsa->mt_blinding instead */
293
294 *local = 0; /* instructs rsa_blinding_convert(), rsa_blinding_invert()
295 * that the BN_BLINDING is shared, meaning that accesses
296 * require locks, and that the blinding factor must be
297 * stored outside the BN_BLINDING
298 */
299
56276539
SS
300 if (rsa->mt_blinding == NULL)
301 {
74093195
SS
302 if (!got_write_lock)
303 {
304 CRYPTO_r_unlock(CRYPTO_LOCK_RSA);
305 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
306 got_write_lock = 1;
307 }
308
56276539
SS
309 if (rsa->mt_blinding == NULL)
310 rsa->mt_blinding = RSA_setup_blinding(rsa, ctx);
56276539
SS
311 }
312 ret = rsa->mt_blinding;
313 }
56276539 314
74093195
SS
315 err:
316 if (got_write_lock)
317 CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
318 else
319 CRYPTO_r_unlock(CRYPTO_LOCK_RSA);
56276539
SS
320 return ret;
321}
322
323static int rsa_blinding_convert(BN_BLINDING *b, int local, BIGNUM *f,
324 BIGNUM *r, BN_CTX *ctx)
325{
326 if (local)
327 return BN_BLINDING_convert_ex(f, NULL, b, ctx);
328 else
329 {
330 int ret;
5bd86ce5 331 CRYPTO_r_lock(CRYPTO_LOCK_RSA_BLINDING);
56276539 332 ret = BN_BLINDING_convert_ex(f, r, b, ctx);
5bd86ce5 333 CRYPTO_r_unlock(CRYPTO_LOCK_RSA_BLINDING);
56276539
SS
334 return ret;
335 }
336}
337
338static int rsa_blinding_invert(BN_BLINDING *b, int local, BIGNUM *f,
339 BIGNUM *r, BN_CTX *ctx)
340{
341 if (local)
342 return BN_BLINDING_invert_ex(f, NULL, b, ctx);
343 else
344 {
345 int ret;
5bd86ce5 346 CRYPTO_w_lock(CRYPTO_LOCK_RSA_BLINDING);
56276539 347 ret = BN_BLINDING_invert_ex(f, r, b, ctx);
5bd86ce5 348 CRYPTO_w_unlock(CRYPTO_LOCK_RSA_BLINDING);
56276539
SS
349 return ret;
350 }
351}
352
353/* signing */
354static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
355 unsigned char *to, RSA *rsa, int padding)
356 {
357 BIGNUM *f, *ret, *br, *res;
358 int i,j,k,num=0,r= -1;
359 unsigned char *buf=NULL;
360 BN_CTX *ctx=NULL;
361 int local_blinding = 0;
362 BN_BLINDING *blinding = NULL;
363
364 if ((ctx=BN_CTX_new()) == NULL) goto err;
365 BN_CTX_start(ctx);
366 f = BN_CTX_get(ctx);
367 br = BN_CTX_get(ctx);
368 ret = BN_CTX_get(ctx);
369 num = BN_num_bytes(rsa->n);
370 buf = OPENSSL_malloc(num);
371 if(!f || !ret || !buf)
372 {
373 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,ERR_R_MALLOC_FAILURE);
374 goto err;
375 }
376
377 switch (padding)
378 {
379 case RSA_PKCS1_PADDING:
380 i=RSA_padding_add_PKCS1_type_1(buf,num,from,flen);
381 break;
382 case RSA_X931_PADDING:
383 i=RSA_padding_add_X931(buf,num,from,flen);
384 break;
385 case RSA_NO_PADDING:
386 i=RSA_padding_add_none(buf,num,from,flen);
387 break;
388 case RSA_SSLV23_PADDING:
389 default:
390 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
391 goto err;
392 }
393 if (i <= 0) goto err;
394
395 if (BN_bin2bn(buf,num,f) == NULL) goto err;
396
397 if (BN_ucmp(f, rsa->n) >= 0)
398 {
399 /* usually the padding functions would catch this */
400 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
401 goto err;
402 }
403
404 if (!(rsa->flags & RSA_FLAG_NO_BLINDING))
405 {
74093195 406 blinding = rsa_get_blinding(rsa, &local_blinding, ctx);
56276539
SS
407 if (blinding == NULL)
408 {
409 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT, ERR_R_INTERNAL_ERROR);
410 goto err;
411 }
412 }
413
414 if (blinding != NULL)
415 if (!rsa_blinding_convert(blinding, local_blinding, f, br, ctx))
416 goto err;
417
418 if ( (rsa->flags & RSA_FLAG_EXT_PKEY) ||
419 ((rsa->p != NULL) &&
420 (rsa->q != NULL) &&
421 (rsa->dmp1 != NULL) &&
422 (rsa->dmq1 != NULL) &&
423 (rsa->iqmp != NULL)) )
424 {
425 if (!rsa->meth->rsa_mod_exp(ret, f, rsa, ctx)) goto err;
426 }
427 else
428 {
429 BIGNUM local_d;
430 BIGNUM *d = NULL;
431
e6bc27f5 432 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
56276539
SS
433 {
434 BN_init(&local_d);
435 d = &local_d;
e6bc27f5 436 BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
56276539
SS
437 }
438 else
439 d = rsa->d;
440
441 MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
442
443 if (!rsa->meth->bn_mod_exp(ret,f,d,rsa->n,ctx,
444 rsa->_method_mod_n)) goto err;
445 }
446
447 if (blinding)
448 if (!rsa_blinding_invert(blinding, local_blinding, ret, br, ctx))
449 goto err;
450
451 if (padding == RSA_X931_PADDING)
452 {
453 BN_sub(f, rsa->n, ret);
454 if (BN_cmp(ret, f))
455 res = f;
456 else
457 res = ret;
458 }
459 else
460 res = ret;
461
462 /* put in leading 0 bytes if the number is less than the
463 * length of the modulus */
464 j=BN_num_bytes(res);
465 i=BN_bn2bin(res,&(to[num-j]));
466 for (k=0; k<(num-i); k++)
467 to[k]=0;
468
469 r=num;
470err:
471 if (ctx != NULL)
472 {
473 BN_CTX_end(ctx);
474 BN_CTX_free(ctx);
475 }
476 if (buf != NULL)
477 {
478 OPENSSL_cleanse(buf,num);
479 OPENSSL_free(buf);
480 }
481 return(r);
482 }
483
484static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
485 unsigned char *to, RSA *rsa, int padding)
486 {
487 BIGNUM *f, *ret, *br;
488 int j,num=0,r= -1;
489 unsigned char *p;
490 unsigned char *buf=NULL;
491 BN_CTX *ctx=NULL;
492 int local_blinding = 0;
493 BN_BLINDING *blinding = NULL;
494
495 if((ctx = BN_CTX_new()) == NULL) goto err;
496 BN_CTX_start(ctx);
497 f = BN_CTX_get(ctx);
498 br = BN_CTX_get(ctx);
499 ret = BN_CTX_get(ctx);
500 num = BN_num_bytes(rsa->n);
501 buf = OPENSSL_malloc(num);
502 if(!f || !ret || !buf)
503 {
504 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,ERR_R_MALLOC_FAILURE);
505 goto err;
506 }
507
508 /* This check was for equality but PGP does evil things
509 * and chops off the top '0' bytes */
510 if (flen > num)
511 {
512 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_DATA_GREATER_THAN_MOD_LEN);
513 goto err;
514 }
515
516 /* make data into a big number */
517 if (BN_bin2bn(from,(int)flen,f) == NULL) goto err;
518
519 if (BN_ucmp(f, rsa->n) >= 0)
520 {
521 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
522 goto err;
523 }
524
525 if (!(rsa->flags & RSA_FLAG_NO_BLINDING))
526 {
74093195 527 blinding = rsa_get_blinding(rsa, &local_blinding, ctx);
56276539
SS
528 if (blinding == NULL)
529 {
530 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT, ERR_R_INTERNAL_ERROR);
531 goto err;
532 }
533 }
534
535 if (blinding != NULL)
536 if (!rsa_blinding_convert(blinding, local_blinding, f, br, ctx))
537 goto err;
538
539 /* do the decrypt */
540 if ( (rsa->flags & RSA_FLAG_EXT_PKEY) ||
541 ((rsa->p != NULL) &&
542 (rsa->q != NULL) &&
543 (rsa->dmp1 != NULL) &&
544 (rsa->dmq1 != NULL) &&
545 (rsa->iqmp != NULL)) )
546 {
547 if (!rsa->meth->rsa_mod_exp(ret, f, rsa, ctx)) goto err;
548 }
549 else
550 {
551 BIGNUM local_d;
552 BIGNUM *d = NULL;
553
e6bc27f5 554 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
56276539
SS
555 {
556 d = &local_d;
e6bc27f5 557 BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
56276539
SS
558 }
559 else
560 d = rsa->d;
561
562 MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
563 if (!rsa->meth->bn_mod_exp(ret,f,d,rsa->n,ctx,
564 rsa->_method_mod_n))
565 goto err;
566 }
567
568 if (blinding)
569 if (!rsa_blinding_invert(blinding, local_blinding, ret, br, ctx))
570 goto err;
571
572 p=buf;
573 j=BN_bn2bin(ret,p); /* j is only used with no-padding mode */
574
575 switch (padding)
576 {
577 case RSA_PKCS1_PADDING:
578 r=RSA_padding_check_PKCS1_type_2(to,num,buf,j,num);
579 break;
580#ifndef OPENSSL_NO_SHA
581 case RSA_PKCS1_OAEP_PADDING:
582 r=RSA_padding_check_PKCS1_OAEP(to,num,buf,j,num,NULL,0);
583 break;
584#endif
585 case RSA_SSLV23_PADDING:
586 r=RSA_padding_check_SSLv23(to,num,buf,j,num);
587 break;
588 case RSA_NO_PADDING:
589 r=RSA_padding_check_none(to,num,buf,j,num);
590 break;
591 default:
592 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
593 goto err;
594 }
595 if (r < 0)
596 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_PADDING_CHECK_FAILED);
597
598err:
599 if (ctx != NULL)
600 {
601 BN_CTX_end(ctx);
602 BN_CTX_free(ctx);
603 }
604 if (buf != NULL)
605 {
606 OPENSSL_cleanse(buf,num);
607 OPENSSL_free(buf);
608 }
609 return(r);
610 }
611
612/* signature verification */
613static int RSA_eay_public_decrypt(int flen, const unsigned char *from,
614 unsigned char *to, RSA *rsa, int padding)
615 {
616 BIGNUM *f,*ret;
617 int i,num=0,r= -1;
618 unsigned char *p;
619 unsigned char *buf=NULL;
620 BN_CTX *ctx=NULL;
621
3b25c29b
PA
622 if (BN_num_bits(rsa->n) > OPENSSL_RSA_MAX_MODULUS_BITS)
623 {
624 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_MODULUS_TOO_LARGE);
625 return -1;
626 }
627
628 if (BN_ucmp(rsa->n, rsa->e) <= 0)
629 {
630 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_BAD_E_VALUE);
631 return -1;
632 }
633
634 /* for large moduli, enforce exponent limit */
635 if (BN_num_bits(rsa->n) > OPENSSL_RSA_SMALL_MODULUS_BITS)
636 {
637 if (BN_num_bits(rsa->e) > OPENSSL_RSA_MAX_PUBEXP_BITS)
638 {
639 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_BAD_E_VALUE);
640 return -1;
641 }
642 }
643
56276539
SS
644 if((ctx = BN_CTX_new()) == NULL) goto err;
645 BN_CTX_start(ctx);
646 f = BN_CTX_get(ctx);
647 ret = BN_CTX_get(ctx);
648 num=BN_num_bytes(rsa->n);
649 buf = OPENSSL_malloc(num);
650 if(!f || !ret || !buf)
651 {
652 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,ERR_R_MALLOC_FAILURE);
653 goto err;
654 }
655
656 /* This check was for equality but PGP does evil things
657 * and chops off the top '0' bytes */
658 if (flen > num)
659 {
660 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_DATA_GREATER_THAN_MOD_LEN);
661 goto err;
662 }
663
664 if (BN_bin2bn(from,flen,f) == NULL) goto err;
665
666 if (BN_ucmp(f, rsa->n) >= 0)
667 {
668 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
669 goto err;
670 }
671
672 MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
673
674 if (!rsa->meth->bn_mod_exp(ret,f,rsa->e,rsa->n,ctx,
675 rsa->_method_mod_n)) goto err;
676
677 if ((padding == RSA_X931_PADDING) && ((ret->d[0] & 0xf) != 12))
678 BN_sub(ret, rsa->n, ret);
679
680 p=buf;
681 i=BN_bn2bin(ret,p);
682
683 switch (padding)
684 {
685 case RSA_PKCS1_PADDING:
686 r=RSA_padding_check_PKCS1_type_1(to,num,buf,i,num);
687 break;
688 case RSA_X931_PADDING:
689 r=RSA_padding_check_X931(to,num,buf,i,num);
690 break;
691 case RSA_NO_PADDING:
692 r=RSA_padding_check_none(to,num,buf,i,num);
693 break;
694 default:
695 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
696 goto err;
697 }
698 if (r < 0)
699 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_PADDING_CHECK_FAILED);
700
701err:
702 if (ctx != NULL)
703 {
704 BN_CTX_end(ctx);
705 BN_CTX_free(ctx);
706 }
707 if (buf != NULL)
708 {
709 OPENSSL_cleanse(buf,num);
710 OPENSSL_free(buf);
711 }
712 return(r);
713 }
714
715static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa, BN_CTX *ctx)
716 {
717 BIGNUM *r1,*m1,*vrfy;
e6bc27f5
PA
718 BIGNUM local_dmp1,local_dmq1,local_c,local_r1;
719 BIGNUM *dmp1,*dmq1,*c,*pr1;
720 int bn_flags;
56276539
SS
721 int ret=0;
722
723 BN_CTX_start(ctx);
724 r1 = BN_CTX_get(ctx);
725 m1 = BN_CTX_get(ctx);
726 vrfy = BN_CTX_get(ctx);
727
e6bc27f5
PA
728 /* Make sure mod_inverse in montgomerey intialization use correct
729 * BN_FLG_CONSTTIME flag.
730 */
731 bn_flags = rsa->p->flags;
732 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
733 {
734 rsa->p->flags |= BN_FLG_CONSTTIME;
735 }
56276539 736 MONT_HELPER(rsa, ctx, p, rsa->flags & RSA_FLAG_CACHE_PRIVATE, goto err);
e6bc27f5
PA
737 /* We restore bn_flags back */
738 rsa->p->flags = bn_flags;
739
740 /* Make sure mod_inverse in montgomerey intialization use correct
741 * BN_FLG_CONSTTIME flag.
742 */
743 bn_flags = rsa->q->flags;
744 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
745 {
746 rsa->q->flags |= BN_FLG_CONSTTIME;
747 }
56276539 748 MONT_HELPER(rsa, ctx, q, rsa->flags & RSA_FLAG_CACHE_PRIVATE, goto err);
e6bc27f5
PA
749 /* We restore bn_flags back */
750 rsa->q->flags = bn_flags;
751
56276539
SS
752 MONT_HELPER(rsa, ctx, n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
753
e6bc27f5
PA
754 /* compute I mod q */
755 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
756 {
757 c = &local_c;
758 BN_with_flags(c, I, BN_FLG_CONSTTIME);
759 if (!BN_mod(r1,c,rsa->q,ctx)) goto err;
760 }
761 else
762 {
763 if (!BN_mod(r1,I,rsa->q,ctx)) goto err;
764 }
765
766 /* compute r1^dmq1 mod q */
767 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
56276539
SS
768 {
769 dmq1 = &local_dmq1;
e6bc27f5 770 BN_with_flags(dmq1, rsa->dmq1, BN_FLG_CONSTTIME);
56276539
SS
771 }
772 else
773 dmq1 = rsa->dmq1;
774 if (!rsa->meth->bn_mod_exp(m1,r1,dmq1,rsa->q,ctx,
775 rsa->_method_mod_q)) goto err;
776
e6bc27f5
PA
777 /* compute I mod p */
778 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
779 {
780 c = &local_c;
781 BN_with_flags(c, I, BN_FLG_CONSTTIME);
782 if (!BN_mod(r1,c,rsa->p,ctx)) goto err;
783 }
784 else
785 {
786 if (!BN_mod(r1,I,rsa->p,ctx)) goto err;
787 }
788
789 /* compute r1^dmp1 mod p */
790 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
56276539
SS
791 {
792 dmp1 = &local_dmp1;
e6bc27f5 793 BN_with_flags(dmp1, rsa->dmp1, BN_FLG_CONSTTIME);
56276539
SS
794 }
795 else
796 dmp1 = rsa->dmp1;
797 if (!rsa->meth->bn_mod_exp(r0,r1,dmp1,rsa->p,ctx,
798 rsa->_method_mod_p)) goto err;
799
800 if (!BN_sub(r0,r0,m1)) goto err;
801 /* This will help stop the size of r0 increasing, which does
802 * affect the multiply if it optimised for a power of 2 size */
803 if (BN_is_negative(r0))
804 if (!BN_add(r0,r0,rsa->p)) goto err;
805
806 if (!BN_mul(r1,r0,rsa->iqmp,ctx)) goto err;
e6bc27f5
PA
807
808 /* Turn BN_FLG_CONSTTIME flag on before division operation */
809 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
810 {
811 pr1 = &local_r1;
812 BN_with_flags(pr1, r1, BN_FLG_CONSTTIME);
813 }
814 else
815 pr1 = r1;
816 if (!BN_mod(r0,pr1,rsa->p,ctx)) goto err;
817
56276539
SS
818 /* If p < q it is occasionally possible for the correction of
819 * adding 'p' if r0 is negative above to leave the result still
820 * negative. This can break the private key operations: the following
821 * second correction should *always* correct this rare occurrence.
822 * This will *never* happen with OpenSSL generated keys because
823 * they ensure p > q [steve]
824 */
825 if (BN_is_negative(r0))
826 if (!BN_add(r0,r0,rsa->p)) goto err;
827 if (!BN_mul(r1,r0,rsa->q,ctx)) goto err;
828 if (!BN_add(r0,r1,m1)) goto err;
829
830 if (rsa->e && rsa->n)
831 {
832 if (!rsa->meth->bn_mod_exp(vrfy,r0,rsa->e,rsa->n,ctx,rsa->_method_mod_n)) goto err;
833 /* If 'I' was greater than (or equal to) rsa->n, the operation
834 * will be equivalent to using 'I mod n'. However, the result of
835 * the verify will *always* be less than 'n' so we don't check
836 * for absolute equality, just congruency. */
837 if (!BN_sub(vrfy, vrfy, I)) goto err;
838 if (!BN_mod(vrfy, vrfy, rsa->n, ctx)) goto err;
839 if (BN_is_negative(vrfy))
840 if (!BN_add(vrfy, vrfy, rsa->n)) goto err;
841 if (!BN_is_zero(vrfy))
842 {
843 /* 'I' and 'vrfy' aren't congruent mod n. Don't leak
844 * miscalculated CRT output, just do a raw (slower)
845 * mod_exp and return that instead. */
846
847 BIGNUM local_d;
848 BIGNUM *d = NULL;
849
e6bc27f5 850 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
56276539
SS
851 {
852 d = &local_d;
e6bc27f5 853 BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
56276539
SS
854 }
855 else
856 d = rsa->d;
857 if (!rsa->meth->bn_mod_exp(r0,I,d,rsa->n,ctx,
858 rsa->_method_mod_n)) goto err;
859 }
860 }
861 ret=1;
862err:
863 BN_CTX_end(ctx);
864 return(ret);
865 }
866
867static int RSA_eay_init(RSA *rsa)
868 {
869 rsa->flags|=RSA_FLAG_CACHE_PUBLIC|RSA_FLAG_CACHE_PRIVATE;
870 return(1);
871 }
872
873static int RSA_eay_finish(RSA *rsa)
874 {
875 if (rsa->_method_mod_n != NULL)
876 BN_MONT_CTX_free(rsa->_method_mod_n);
877 if (rsa->_method_mod_p != NULL)
878 BN_MONT_CTX_free(rsa->_method_mod_p);
879 if (rsa->_method_mod_q != NULL)
880 BN_MONT_CTX_free(rsa->_method_mod_q);
881 return(1);
882 }
883
884#endif