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
56 int RSA_check_key(const RSA *key)
57 {
58 BIGNUM *i, *j, *k, *l, *m;
59 BN_CTX *ctx;
60 int r;
61 int ret=1;
62
63 if (!key->p || !key->q || !key->n || !key->e || !key->d)
64 {
65 RSAerr(RSA_F_RSA_CHECK_KEY, RSA_R_VALUE_MISSING);
66 return 0;
67 }
68
69 i = BN_new();
70 j = BN_new();
71 k = BN_new();
72 l = BN_new();
73 m = BN_new();
74 ctx = BN_CTX_new();
75 if (i == NULL || j == NULL || k == NULL || l == NULL ||
76 m == NULL || ctx == NULL)
77 {
78 ret = -1;
79 RSAerr(RSA_F_RSA_CHECK_KEY, ERR_R_MALLOC_FAILURE);
80 goto err;
81 }
82
83 /* p prime? */
84 r = BN_is_prime_ex(key->p, BN_prime_checks, NULL, NULL);
85 if (r != 1)
86 {
87 ret = r;
88 if (r != 0)
89 goto err;
90 RSAerr(RSA_F_RSA_CHECK_KEY, RSA_R_P_NOT_PRIME);
91 }
92
93 /* q prime? */
94 r = BN_is_prime_ex(key->q, BN_prime_checks, NULL, NULL);
95 if (r != 1)
96 {
97 ret = r;
98 if (r != 0)
99 goto err;
100 RSAerr(RSA_F_RSA_CHECK_KEY, RSA_R_Q_NOT_PRIME);
101 }
102
103 /* n = p*q? */
104 r = BN_mul(i, key->p, key->q, ctx);
105 if (!r) { ret = -1; goto err; }
106
107 if (BN_cmp(i, key->n) != 0)
108 {
109 ret = 0;
110 RSAerr(RSA_F_RSA_CHECK_KEY, RSA_R_N_DOES_NOT_EQUAL_P_Q);
111 }
112
113 /* d*e = 1 mod lcm(p-1,q-1)? */
114
115 r = BN_sub(i, key->p, BN_value_one());
116 if (!r) { ret = -1; goto err; }
117 r = BN_sub(j, key->q, BN_value_one());
118 if (!r) { ret = -1; goto err; }
119
120 /* now compute k = lcm(i,j) */
121 r = BN_mul(l, i, j, ctx);
122 if (!r) { ret = -1; goto err; }
123 r = BN_gcd(m, i, j, ctx);
124 if (!r) { ret = -1; goto err; }
125 r = BN_div(k, NULL, l, m, ctx); /* remainder is 0 */
126 if (!r) { ret = -1; goto err; }
127
128 r = BN_mod_mul(i, key->d, key->e, k, ctx);
129 if (!r) { ret = -1; goto err; }
130
131 if (!BN_is_one(i))
132 {
133 ret = 0;
134 RSAerr(RSA_F_RSA_CHECK_KEY, RSA_R_D_E_NOT_CONGRUENT_TO_1);
135 }
136
137 if (key->dmp1 != NULL && key->dmq1 != NULL && key->iqmp != NULL)
138 {
139 /* dmp1 = d mod (p-1)? */
140 r = BN_sub(i, key->p, BN_value_one());
141 if (!r) { ret = -1; goto err; }
142
143 r = BN_mod(j, key->d, i, ctx);
144 if (!r) { ret = -1; goto err; }
145
146 if (BN_cmp(j, key->dmp1) != 0)
147 {
148 ret = 0;
149 RSAerr(RSA_F_RSA_CHECK_KEY,
150 RSA_R_DMP1_NOT_CONGRUENT_TO_D);
151 }
152
153 /* dmq1 = d mod (q-1)? */
154 r = BN_sub(i, key->q, BN_value_one());
155 if (!r) { ret = -1; goto err; }
156
157 r = BN_mod(j, key->d, i, ctx);
158 if (!r) { ret = -1; goto err; }
159
160 if (BN_cmp(j, key->dmq1) != 0)
161 {
162 ret = 0;
163 RSAerr(RSA_F_RSA_CHECK_KEY,
164 RSA_R_DMQ1_NOT_CONGRUENT_TO_D);
165 }
166
167 /* iqmp = q^-1 mod p? */
168 if(!BN_mod_inverse(i, key->q, key->p, ctx))
169 {
170 ret = -1;
171 goto err;
172 }
173
174 if (BN_cmp(i, key->iqmp) != 0)
175 {
176 ret = 0;
177 RSAerr(RSA_F_RSA_CHECK_KEY,
178 RSA_R_IQMP_NOT_INVERSE_OF_Q);
179 }
180 }
181
182 err:
183 if (i != NULL) BN_free(i);
184 if (j != NULL) BN_free(j);
185 if (k != NULL) BN_free(k);
186 if (l != NULL) BN_free(l);
187 if (m != NULL) BN_free(m);
188 if (ctx != NULL) BN_CTX_free(ctx);
189 return (ret);
190 }