1 /* $OpenBSD: bn_blind.c,v 1.13 2014/07/11 08:44:47 jsing Exp $ */
2 /* ====================================================================
3 * Copyright (c) 1998-2006 The OpenSSL Project. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in
14 * the documentation and/or other materials provided with the
17 * 3. All advertising materials mentioning features or use of this
18 * software must display the following acknowledgment:
19 * "This product includes software developed by the OpenSSL Project
20 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
22 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
23 * endorse or promote products derived from this software without
24 * prior written permission. For written permission, please contact
25 * openssl-core@openssl.org.
27 * 5. Products derived from this software may not be called "OpenSSL"
28 * nor may "OpenSSL" appear in their names without prior written
29 * permission of the OpenSSL Project.
31 * 6. Redistributions of any form whatsoever must retain the following
33 * "This product includes software developed by the OpenSSL Project
34 * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
36 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
37 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
38 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
39 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
40 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
41 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
42 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
43 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
44 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
45 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
46 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
47 * OF THE POSSIBILITY OF SUCH DAMAGE.
48 * ====================================================================
50 * This product includes cryptographic software written by Eric Young
51 * (eay@cryptsoft.com). This product includes software written by Tim
52 * Hudson (tjh@cryptsoft.com).
55 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
56 * All rights reserved.
58 * This package is an SSL implementation written
59 * by Eric Young (eay@cryptsoft.com).
60 * The implementation was written so as to conform with Netscapes SSL.
62 * This library is free for commercial and non-commercial use as long as
63 * the following conditions are aheared to. The following conditions
64 * apply to all code found in this distribution, be it the RC4, RSA,
65 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
66 * included with this distribution is covered by the same copyright terms
67 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
69 * Copyright remains Eric Young's, and as such any Copyright notices in
70 * the code are not to be removed.
71 * If this package is used in a product, Eric Young should be given attribution
72 * as the author of the parts of the library used.
73 * This can be in the form of a textual message at program startup or
74 * in documentation (online or textual) provided with the package.
76 * Redistribution and use in source and binary forms, with or without
77 * modification, are permitted provided that the following conditions
79 * 1. Redistributions of source code must retain the copyright
80 * notice, this list of conditions and the following disclaimer.
81 * 2. Redistributions in binary form must reproduce the above copyright
82 * notice, this list of conditions and the following disclaimer in the
83 * documentation and/or other materials provided with the distribution.
84 * 3. All advertising materials mentioning features or use of this software
85 * must display the following acknowledgement:
86 * "This product includes cryptographic software written by
87 * Eric Young (eay@cryptsoft.com)"
88 * The word 'cryptographic' can be left out if the rouines from the library
89 * being used are not cryptographic related :-).
90 * 4. If you include any Windows specific code (or a derivative thereof) from
91 * the apps directory (application code) you must include an acknowledgement:
92 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
94 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
95 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
96 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
97 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
98 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
99 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
100 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
101 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
102 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
103 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
106 * The licence and distribution terms for any publically available version or
107 * derivative of this code cannot be changed. i.e. this code cannot simply be
108 * copied and put under another distribution licence
109 * [including the GNU Public Licence.]
114 #include <openssl/opensslconf.h>
116 #include <openssl/err.h>
120 #define BN_BLINDING_COUNTER 32
122 struct bn_blinding_st {
126 BIGNUM *mod; /* just a reference */
127 #ifndef OPENSSL_NO_DEPRECATED
128 unsigned long thread_id; /* added in OpenSSL 0.9.6j and 0.9.7b;
129 * used only by crypto/rsa/rsa_eay.c, rsa_lib.c */
135 int (*bn_mod_exp)(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
136 const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *m_ctx);
140 BN_BLINDING_new(const BIGNUM *A, const BIGNUM *Ai, BIGNUM *mod)
142 BN_BLINDING *ret = NULL;
146 if ((ret = calloc(1, sizeof(BN_BLINDING))) == NULL) {
147 BNerr(BN_F_BN_BLINDING_NEW, ERR_R_MALLOC_FAILURE);
151 if ((ret->A = BN_dup(A)) == NULL)
155 if ((ret->Ai = BN_dup(Ai)) == NULL)
159 /* save a copy of mod in the BN_BLINDING structure */
160 if ((ret->mod = BN_dup(mod)) == NULL)
162 if (BN_get_flags(mod, BN_FLG_CONSTTIME) != 0)
163 BN_set_flags(ret->mod, BN_FLG_CONSTTIME);
165 /* Set the counter to the special value -1
166 * to indicate that this is never-used fresh blinding
167 * that does not need updating before first use. */
169 CRYPTO_THREADID_current(&ret->tid);
174 BN_BLINDING_free(ret);
179 BN_BLINDING_free(BN_BLINDING *r)
185 BN_clear_free(r->Ai);
187 BN_clear_free(r->mod);
192 BN_BLINDING_update(BN_BLINDING *b, BN_CTX *ctx)
196 if ((b->A == NULL) || (b->Ai == NULL)) {
197 BNerr(BN_F_BN_BLINDING_UPDATE, BN_R_NOT_INITIALIZED);
201 if (b->counter == -1)
204 if (++b->counter == BN_BLINDING_COUNTER && b->e != NULL &&
205 !(b->flags & BN_BLINDING_NO_RECREATE)) {
206 /* re-create blinding parameters */
207 if (!BN_BLINDING_create_param(b, NULL, NULL, ctx, NULL, NULL))
209 } else if (!(b->flags & BN_BLINDING_NO_UPDATE)) {
210 if (!BN_mod_mul(b->A, b->A, b->A, b->mod, ctx))
212 if (!BN_mod_mul(b->Ai, b->Ai, b->Ai, b->mod, ctx))
219 if (b->counter == BN_BLINDING_COUNTER)
225 BN_BLINDING_convert(BIGNUM *n, BN_BLINDING *b, BN_CTX *ctx)
227 return BN_BLINDING_convert_ex(n, NULL, b, ctx);
231 BN_BLINDING_convert_ex(BIGNUM *n, BIGNUM *r, BN_BLINDING *b, BN_CTX *ctx)
237 if ((b->A == NULL) || (b->Ai == NULL)) {
238 BNerr(BN_F_BN_BLINDING_CONVERT_EX, BN_R_NOT_INITIALIZED);
242 if (b->counter == -1)
243 /* Fresh blinding, doesn't need updating. */
245 else if (!BN_BLINDING_update(b, ctx))
249 if (!BN_copy(r, b->Ai))
253 if (!BN_mod_mul(n, n,b->A, b->mod, ctx))
260 BN_BLINDING_invert(BIGNUM *n, BN_BLINDING *b, BN_CTX *ctx)
262 return BN_BLINDING_invert_ex(n, NULL, b, ctx);
266 BN_BLINDING_invert_ex(BIGNUM *n, const BIGNUM *r, BN_BLINDING *b, BN_CTX *ctx)
273 ret = BN_mod_mul(n, n, r, b->mod, ctx);
276 BNerr(BN_F_BN_BLINDING_INVERT_EX, BN_R_NOT_INITIALIZED);
279 ret = BN_mod_mul(n, n, b->Ai, b->mod, ctx);
286 #ifndef OPENSSL_NO_DEPRECATED
288 BN_BLINDING_get_thread_id(const BN_BLINDING *b)
294 BN_BLINDING_set_thread_id(BN_BLINDING *b, unsigned long n)
301 BN_BLINDING_thread_id(BN_BLINDING *b)
307 BN_BLINDING_get_flags(const BN_BLINDING *b)
313 BN_BLINDING_set_flags(BN_BLINDING *b, unsigned long flags)
319 BN_BLINDING_create_param(BN_BLINDING *b, const BIGNUM *e, BIGNUM *m,
320 BN_CTX *ctx, int (*bn_mod_exp)(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
321 const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *m_ctx), BN_MONT_CTX *m_ctx)
323 int retry_counter = 32;
324 BN_BLINDING *ret = NULL;
327 ret = BN_BLINDING_new(NULL, NULL, m);
334 if (ret->A == NULL && (ret->A = BN_new()) == NULL)
336 if (ret->Ai == NULL && (ret->Ai = BN_new()) == NULL)
346 if (bn_mod_exp != NULL)
347 ret->bn_mod_exp = bn_mod_exp;
352 if (!BN_rand_range(ret->A, ret->mod))
354 if (BN_mod_inverse(ret->Ai, ret->A, ret->mod, ctx) == NULL) {
355 /* this should almost never happen for good RSA keys */
356 unsigned long error = ERR_peek_last_error();
357 if (ERR_GET_REASON(error) == BN_R_NO_INVERSE) {
358 if (retry_counter-- == 0) {
359 BNerr(BN_F_BN_BLINDING_CREATE_PARAM,
360 BN_R_TOO_MANY_ITERATIONS);
370 if (ret->bn_mod_exp != NULL && ret->m_ctx != NULL) {
371 if (!ret->bn_mod_exp(ret->A, ret->A, ret->e, ret->mod,
375 if (!BN_mod_exp(ret->A, ret->A, ret->e, ret->mod, ctx))
382 if (b == NULL && ret != NULL) {
383 BN_BLINDING_free(ret);