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 55int 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 if (!key->p || !key->q || !key->n || !key->e || !key->d) { 63 RSAerr(RSA_F_RSA_CHECK_KEY, RSA_R_VALUE_MISSING); 64 return 0; 65 } 66 67 i = BN_new(); 68 j = BN_new(); 69 k = BN_new(); 70 l = BN_new(); 71 m = BN_new(); 72 ctx = BN_CTX_new(); 73 if (i == NULL || j == NULL || k == NULL || l == NULL || 74 m == NULL || ctx == NULL) { 75 ret = -1; 76 RSAerr(RSA_F_RSA_CHECK_KEY, ERR_R_MALLOC_FAILURE); 77 goto err; 78 } 79 80 /* p prime? */ 81 r = BN_is_prime_ex(key->p, BN_prime_checks, NULL, NULL); 82 if (r != 1) { 83 ret = r; 84 if (r != 0) 85 goto err; 86 RSAerr(RSA_F_RSA_CHECK_KEY, RSA_R_P_NOT_PRIME); 87 } 88 89 /* q prime? */ 90 r = BN_is_prime_ex(key->q, BN_prime_checks, NULL, NULL); 91 if (r != 1) { 92 ret = r; 93 if (r != 0) 94 goto err; 95 RSAerr(RSA_F_RSA_CHECK_KEY, RSA_R_Q_NOT_PRIME); 96 } 97 98 /* n = p*q? */ 99 r = BN_mul(i, key->p, key->q, ctx); 100 if (!r) { 101 ret = -1; 102 goto err; 103 } 104 105 if (BN_cmp(i, key->n) != 0) { 106 ret = 0; 107 RSAerr(RSA_F_RSA_CHECK_KEY, RSA_R_N_DOES_NOT_EQUAL_P_Q); 108 } 109 110 /* d*e = 1 mod lcm(p-1,q-1)? */ 111 112 r = BN_sub(i, key->p, BN_value_one()); 113 if (!r) { 114 ret = -1; 115 goto err; 116 } 117 r = BN_sub(j, key->q, BN_value_one()); 118 if (!r) { 119 ret = -1; 120 goto err; 121 } 122 123 /* now compute k = lcm(i,j) */ 124 r = BN_mul(l, i, j, ctx); 125 if (!r) { 126 ret = -1; 127 goto err; 128 } 129 r = BN_gcd(m, i, j, ctx); 130 if (!r) { 131 ret = -1; 132 goto err; 133 } 134 r = BN_div(k, NULL, l, m, ctx); /* remainder is 0 */ 135 if (!r) { 136 ret = -1; 137 goto err; 138 } 139 140 r = BN_mod_mul(i, key->d, key->e, k, ctx); 141 if (!r) { 142 ret = -1; 143 goto err; 144 } 145 146 if (!BN_is_one(i)) { 147 ret = 0; 148 RSAerr(RSA_F_RSA_CHECK_KEY, RSA_R_D_E_NOT_CONGRUENT_TO_1); 149 } 150 151 if (key->dmp1 != NULL && key->dmq1 != NULL && key->iqmp != NULL) { 152 /* dmp1 = d mod (p-1)? */ 153 r = BN_sub(i, key->p, BN_value_one()); 154 if (!r) { 155 ret = -1; 156 goto err; 157 } 158 159 r = BN_mod(j, key->d, i, ctx); 160 if (!r) { 161 ret = -1; 162 goto err; 163 } 164 165 if (BN_cmp(j, key->dmp1) != 0) { 166 ret = 0; 167 RSAerr(RSA_F_RSA_CHECK_KEY, RSA_R_DMP1_NOT_CONGRUENT_TO_D); 168 } 169 170 /* dmq1 = d mod (q-1)? */ 171 r = BN_sub(i, key->q, BN_value_one()); 172 if (!r) { 173 ret = -1; 174 goto err; 175 } 176 177 r = BN_mod(j, key->d, i, ctx); 178 if (!r) { 179 ret = -1; 180 goto err; 181 } 182 183 if (BN_cmp(j, key->dmq1) != 0) { 184 ret = 0; 185 RSAerr(RSA_F_RSA_CHECK_KEY, RSA_R_DMQ1_NOT_CONGRUENT_TO_D); 186 } 187 188 /* iqmp = q^-1 mod p? */ 189 if (!BN_mod_inverse(i, key->q, key->p, ctx)) { 190 ret = -1; 191 goto err; 192 } 193 194 if (BN_cmp(i, key->iqmp) != 0) { 195 ret = 0; 196 RSAerr(RSA_F_RSA_CHECK_KEY, RSA_R_IQMP_NOT_INVERSE_OF_Q); 197 } 198 } 199 200 err: 201 if (i != NULL) 202 BN_free(i); 203 if (j != NULL) 204 BN_free(j); 205 if (k != NULL) 206 BN_free(k); 207 if (l != NULL) 208 BN_free(l); 209 if (m != NULL) 210 BN_free(m); 211 if (ctx != NULL) 212 BN_CTX_free(ctx); 213 return (ret); 214} 215