1 /* crypto/bn/bn_blind.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
59 #include <stdio.h>
60 #include "cryptlib.h"
61 #include "bn_lcl.h"
62
BN_BLINDING_new(BIGNUM * A,BIGNUM * Ai,BIGNUM * mod)63 BN_BLINDING *BN_BLINDING_new(BIGNUM *A, BIGNUM *Ai, BIGNUM *mod)
64 {
65 BN_BLINDING *ret=NULL;
66
67 bn_check_top(Ai);
68 bn_check_top(mod);
69
70 if ((ret=(BN_BLINDING *)OPENSSL_malloc(sizeof(BN_BLINDING))) == NULL)
71 {
72 BNerr(BN_F_BN_BLINDING_NEW,ERR_R_MALLOC_FAILURE);
73 return(NULL);
74 }
75 memset(ret,0,sizeof(BN_BLINDING));
76 if ((ret->A=BN_new()) == NULL) goto err;
77 if ((ret->Ai=BN_new()) == NULL) goto err;
78 if (!BN_copy(ret->A,A)) goto err;
79 if (!BN_copy(ret->Ai,Ai)) goto err;
80 ret->mod=mod;
81 return(ret);
82 err:
83 if (ret != NULL) BN_BLINDING_free(ret);
84 return(NULL);
85 }
86
BN_BLINDING_free(BN_BLINDING * r)87 void BN_BLINDING_free(BN_BLINDING *r)
88 {
89 if(r == NULL)
90 return;
91
92 if (r->A != NULL) BN_free(r->A );
93 if (r->Ai != NULL) BN_free(r->Ai);
94 OPENSSL_free(r);
95 }
96
BN_BLINDING_update(BN_BLINDING * b,BN_CTX * ctx)97 int BN_BLINDING_update(BN_BLINDING *b, BN_CTX *ctx)
98 {
99 int ret=0;
100
101 if ((b->A == NULL) || (b->Ai == NULL))
102 {
103 BNerr(BN_F_BN_BLINDING_UPDATE,BN_R_NOT_INITIALIZED);
104 goto err;
105 }
106
107 if (!BN_mod_mul(b->A,b->A,b->A,b->mod,ctx)) goto err;
108 if (!BN_mod_mul(b->Ai,b->Ai,b->Ai,b->mod,ctx)) goto err;
109
110 ret=1;
111 err:
112 return(ret);
113 }
114
BN_BLINDING_convert(BIGNUM * n,BN_BLINDING * b,BN_CTX * ctx)115 int BN_BLINDING_convert(BIGNUM *n, BN_BLINDING *b, BN_CTX *ctx)
116 {
117 bn_check_top(n);
118
119 if ((b->A == NULL) || (b->Ai == NULL))
120 {
121 BNerr(BN_F_BN_BLINDING_CONVERT,BN_R_NOT_INITIALIZED);
122 return(0);
123 }
124 return(BN_mod_mul(n,n,b->A,b->mod,ctx));
125 }
126
BN_BLINDING_invert(BIGNUM * n,BN_BLINDING * b,BN_CTX * ctx)127 int BN_BLINDING_invert(BIGNUM *n, BN_BLINDING *b, BN_CTX *ctx)
128 {
129 int ret;
130
131 bn_check_top(n);
132 if ((b->A == NULL) || (b->Ai == NULL))
133 {
134 BNerr(BN_F_BN_BLINDING_INVERT,BN_R_NOT_INITIALIZED);
135 return(0);
136 }
137 if ((ret=BN_mod_mul(n,n,b->Ai,b->mod,ctx)) >= 0)
138 {
139 if (!BN_BLINDING_update(b,ctx))
140 return(0);
141 }
142 return(ret);
143 }
144
145