crypto/openssl-0.9.7d/crypto/bn/bn_blind.c

   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
  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
  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
  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
 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
 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