crypto/rsa/rsa_chk.c

   1 /* crypto/rsa/rsa_chk.c  -*- Mode: C; c-file-style: "eay" -*- */
   2 /* ====================================================================
   3  * Copyright (c) 1999 The OpenSSL Project.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  *
  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
  15  *    distribution.
  16  *
  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/)"
  21  *
  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.
  26  *
  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.
  30  *
  31  * 6. Redistributions of any form whatsoever must retain the following
  32  *    acknowledgment:
  33  *    "This product includes software developed by the OpenSSL Project
  34  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
  35  *
  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  * ====================================================================
  49  */
  50
  51 #include <openssl/bn.h>
  52 #include <openssl/err.h>
  53 #include <openssl/rsa.h>
  54
  55 int RSA_check_key(const RSA *key)
  56 {
  57     BIGNUM *i, *j, *k, *l, *m;
  58     BN_CTX *ctx;
  59     int r;
  60     int ret = 1;
  61
  62     i = BN_new();
  63     j = BN_new();
  64     k = BN_new();
  65     l = BN_new();
  66     m = BN_new();
  67     ctx = BN_CTX_new();
  68     if (i == NULL || j == NULL || k == NULL || l == NULL ||
  69         m == NULL || ctx == NULL) {
  70         ret = -1;
  71         RSAerr(RSA_F_RSA_CHECK_KEY, ERR_R_MALLOC_FAILURE);
  72         goto err;
  73     }
  74
  75     /* p prime? */
  76     r = BN_is_prime_ex(key->p, BN_prime_checks, NULL, NULL);
  77     if (r != 1) {
  78         ret = r;
  79         if (r != 0)
  80             goto err;
  81         RSAerr(RSA_F_RSA_CHECK_KEY, RSA_R_P_NOT_PRIME);
  82     }
  83
  84     /* q prime? */
  85     r = BN_is_prime_ex(key->q, BN_prime_checks, NULL, NULL);
  86     if (r != 1) {
  87         ret = r;
  88         if (r != 0)
  89             goto err;
  90         RSAerr(RSA_F_RSA_CHECK_KEY, RSA_R_Q_NOT_PRIME);
  91     }
  92
  93     /* n = p*q? */
  94     r = BN_mul(i, key->p, key->q, ctx);
  95     if (!r) {
  96         ret = -1;
  97         goto err;
  98     }
  99
 100     if (BN_cmp(i, key->n) != 0) {
 101         ret = 0;
 102         RSAerr(RSA_F_RSA_CHECK_KEY, RSA_R_N_DOES_NOT_EQUAL_P_Q);
 103     }
 104
 105     /* d*e = 1  mod lcm(p-1,q-1)? */
 106
 107     r = BN_sub(i, key->p, BN_value_one());
 108     if (!r) {
 109         ret = -1;
 110         goto err;
 111     }
 112     r = BN_sub(j, key->q, BN_value_one());
 113     if (!r) {
 114         ret = -1;
 115         goto err;
 116     }
 117
 118     /* now compute k = lcm(i,j) */
 119     r = BN_mul(l, i, j, ctx);
 120     if (!r) {
 121         ret = -1;
 122         goto err;
 123     }
 124     r = BN_gcd(m, i, j, ctx);
 125     if (!r) {
 126         ret = -1;
 127         goto err;
 128     }
 129     r = BN_div(k, NULL, l, m, ctx); /* remainder is 0 */
 130     if (!r) {
 131         ret = -1;
 132         goto err;
 133     }
 134
 135     r = BN_mod_mul(i, key->d, key->e, k, ctx);
 136     if (!r) {
 137         ret = -1;
 138         goto err;
 139     }
 140
 141     if (!BN_is_one(i)) {
 142         ret = 0;
 143         RSAerr(RSA_F_RSA_CHECK_KEY, RSA_R_D_E_NOT_CONGRUENT_TO_1);
 144     }
 145
 146     if (key->dmp1 != NULL && key->dmq1 != NULL && key->iqmp != NULL) {
 147         /* dmp1 = d mod (p-1)? */
 148         r = BN_sub(i, key->p, BN_value_one());
 149         if (!r) {
 150             ret = -1;
 151             goto err;
 152         }
 153
 154         r = BN_mod(j, key->d, i, ctx);
 155         if (!r) {
 156             ret = -1;
 157             goto err;
 158         }
 159
 160         if (BN_cmp(j, key->dmp1) != 0) {
 161             ret = 0;
 162             RSAerr(RSA_F_RSA_CHECK_KEY, RSA_R_DMP1_NOT_CONGRUENT_TO_D);
 163         }
 164
 165         /* dmq1 = d mod (q-1)? */
 166         r = BN_sub(i, key->q, BN_value_one());
 167         if (!r) {
 168             ret = -1;
 169             goto err;
 170         }
 171
 172         r = BN_mod(j, key->d, i, ctx);
 173         if (!r) {
 174             ret = -1;
 175             goto err;
 176         }
 177
 178         if (BN_cmp(j, key->dmq1) != 0) {
 179             ret = 0;
 180             RSAerr(RSA_F_RSA_CHECK_KEY, RSA_R_DMQ1_NOT_CONGRUENT_TO_D);
 181         }
 182
 183         /* iqmp = q^-1 mod p? */
 184         if (!BN_mod_inverse(i, key->q, key->p, ctx)) {
 185             ret = -1;
 186             goto err;
 187         }
 188
 189         if (BN_cmp(i, key->iqmp) != 0) {
 190             ret = 0;
 191             RSAerr(RSA_F_RSA_CHECK_KEY, RSA_R_IQMP_NOT_INVERSE_OF_Q);
 192         }
 193     }
 194
 195  err:
 196     if (i != NULL)
 197         BN_free(i);
 198     if (j != NULL)
 199         BN_free(j);
 200     if (k != NULL)
 201         BN_free(k);
 202     if (l != NULL)
 203         BN_free(l);
 204     if (m != NULL)
 205         BN_free(m);
 206     if (ctx != NULL)
 207         BN_CTX_free(ctx);
 208     return (ret);
 209 }