crypto/rsa/rsa_gen.c

   1 /* crypto/rsa/rsa_gen.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
  60 /* NB: these functions have been "upgraded", the deprecated versions (which are
  61  * compatibility wrappers using these functions) are in rsa_depr.c.
  62  * - Geoff
  63  */
  64
  65 #include <stdio.h>
  66 #include <time.h>
  67 #include "cryptlib.h"
  68 #include <openssl/bn.h>
  69 #include <openssl/rsa.h>
  70
  71 int RSA_generate_key_ex(RSA *rsa, int bits, unsigned long e_value, BN_GENCB *cb)
  72         {
  73         BIGNUM *r0=NULL,*r1=NULL,*r2=NULL,*r3=NULL,*tmp;
  74         int bitsp,bitsq,ok= -1,n=0,i;
  75         BN_CTX *ctx=NULL,*ctx2=NULL;
  76
  77         ctx=BN_CTX_new();
  78         if (ctx == NULL) goto err;
  79         ctx2=BN_CTX_new();
  80         if (ctx2 == NULL) goto err;
  81         BN_CTX_start(ctx);
  82         r0 = BN_CTX_get(ctx);
  83         r1 = BN_CTX_get(ctx);
  84         r2 = BN_CTX_get(ctx);
  85         r3 = BN_CTX_get(ctx);
  86         if (r3 == NULL) goto err;
  87
  88         bitsp=(bits+1)/2;
  89         bitsq=bits-bitsp;
  90
  91         /* We need the RSA components non-NULL */
  92         if(!rsa->n && ((rsa->n=BN_new()) == NULL)) goto err;
  93         if(!rsa->d && ((rsa->d=BN_new()) == NULL)) goto err;
  94         if(!rsa->e && ((rsa->e=BN_new()) == NULL)) goto err;
  95         if(!rsa->p && ((rsa->p=BN_new()) == NULL)) goto err;
  96         if(!rsa->q && ((rsa->q=BN_new()) == NULL)) goto err;
  97         if(!rsa->dmp1 && ((rsa->dmp1=BN_new()) == NULL)) goto err;
  98         if(!rsa->dmq1 && ((rsa->dmq1=BN_new()) == NULL)) goto err;
  99         if(!rsa->iqmp && ((rsa->iqmp=BN_new()) == NULL)) goto err;
 100
 101 #if 1
 102         /* The problem is when building with 8, 16, or 32 BN_ULONG,
 103          * unsigned long can be larger */
 104         for (i=0; i<sizeof(unsigned long)*8; i++)
 105                 {
 106                 if (e_value & (1UL<<i))
 107                         BN_set_bit(rsa->e,i);
 108                 }
 109 #else
 110         if (!BN_set_word(rsa->e,e_value)) goto err;
 111 #endif
 112
 113         /* generate p and q */
 114         for (;;)
 115                 {
 116                 if(!BN_generate_prime_ex(rsa->p, bitsp, 0, NULL, NULL, cb))
 117                         goto err;
 118                 if (!BN_sub(r2,rsa->p,BN_value_one())) goto err;
 119                 if (!BN_gcd(r1,r2,rsa->e,ctx)) goto err;
 120                 if (BN_is_one(r1)) break;
 121                 if(!BN_GENCB_call(cb, 2, n++))
 122                         goto err;
 123                 }
 124         if(!BN_GENCB_call(cb, 3, 0))
 125                 goto err;
 126         for (;;)
 127                 {
 128                 if(!BN_generate_prime_ex(rsa->q, bitsq, 0, NULL, NULL, cb))
 129                         goto err;
 130                 if (!BN_sub(r2,rsa->q,BN_value_one())) goto err;
 131                 if (!BN_gcd(r1,r2,rsa->e,ctx)) goto err;
 132                 if (BN_is_one(r1) && (BN_cmp(rsa->p,rsa->q) != 0))
 133                         break;
 134                 if(!BN_GENCB_call(cb, 2, n++))
 135                         goto err;
 136                 }
 137         if(!BN_GENCB_call(cb, 3, 1))
 138                 goto err;
 139         if (BN_cmp(rsa->p,rsa->q) < 0)
 140                 {
 141                 tmp=rsa->p;
 142                 rsa->p=rsa->q;
 143                 rsa->q=tmp;
 144                 }
 145
 146         /* calculate n */
 147         if (!BN_mul(rsa->n,rsa->p,rsa->q,ctx)) goto err;
 148
 149         /* calculate d */
 150         if (!BN_sub(r1,rsa->p,BN_value_one())) goto err;        /* p-1 */
 151         if (!BN_sub(r2,rsa->q,BN_value_one())) goto err;        /* q-1 */
 152         if (!BN_mul(r0,r1,r2,ctx)) goto err;    /* (p-1)(q-1) */
 153
 154 /* should not be needed, since gcd(p-1,e) == 1 and gcd(q-1,e) == 1 */
 155 /*      for (;;)
 156                 {
 157                 if (!BN_gcd(r3,r0,rsa->e,ctx)) goto err;
 158                 if (BN_is_one(r3)) break;
 159
 160                 if (1)
 161                         {
 162                         if (!BN_add_word(rsa->e,2L)) goto err;
 163                         continue;
 164                         }
 165                 RSAerr(RSA_F_RSA_GENERATE_KEY,RSA_R_BAD_E_VALUE);
 166                 goto err;
 167                 }
 168 */
 169         rsa->d=BN_mod_inverse(NULL,rsa->e,r0,ctx2);     /* d */
 170         if (rsa->d == NULL) goto err;
 171
 172         /* calculate d mod (p-1) */
 173         rsa->dmp1=BN_new();
 174         if (rsa->dmp1 == NULL) goto err;
 175         if (!BN_mod(rsa->dmp1,rsa->d,r1,ctx)) goto err;
 176
 177         /* calculate d mod (q-1) */
 178         rsa->dmq1=BN_new();
 179         if (rsa->dmq1 == NULL) goto err;
 180         if (!BN_mod(rsa->dmq1,rsa->d,r2,ctx)) goto err;
 181
 182         /* calculate inverse of q mod p */
 183         rsa->iqmp=BN_mod_inverse(NULL,rsa->q,rsa->p,ctx2);
 184         if (rsa->iqmp == NULL) goto err;
 185
 186         ok=1;
 187 err:
 188         if (ok == -1)
 189                 {
 190                 RSAerr(RSA_F_RSA_GENERATE_KEY,ERR_LIB_BN);
 191                 ok=0;
 192                 }
 193         BN_CTX_end(ctx);
 194         BN_CTX_free(ctx);
 195         BN_CTX_free(ctx2);
 196
 197         return ok;
 198         }
 199