rsa_chk.c revision 56083 
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
56int RSA_check_key(RSA *key)
57	{
58	BIGNUM *i, *j, *k, *l, *m;
59	BN_CTX *ctx;
60	int r;
61	int ret=1;
62
63	i = BN_new();
64	j = BN_new();
65	k = BN_new();
66	l = BN_new();
67	m = BN_new();
68	ctx = BN_CTX_new();
69	if (i == NULL || j == NULL || k == NULL || l == NULL ||
70		m == NULL || ctx == NULL)
71		{
72		ret = -1;
73		RSAerr(RSA_F_RSA_CHECK_KEY, ERR_R_MALLOC_FAILURE);
74		goto err;
75		}
76
77	/* p prime? */
78	r = BN_is_prime(key->p, BN_prime_checks, NULL, NULL, NULL);
79	if (r != 1)
80		{
81		ret = r;
82		if (r != 0)
83			goto err;
84		RSAerr(RSA_F_RSA_CHECK_KEY, RSA_R_P_NOT_PRIME);
85		}
86
87	/* q prime? */
88	r = BN_is_prime(key->q, BN_prime_checks, NULL, NULL, NULL);
89	if (r != 1)
90		{
91		ret = r;
92		if (r != 0)
93			goto err;
94		RSAerr(RSA_F_RSA_CHECK_KEY, RSA_R_Q_NOT_PRIME);
95		}
96
97	/* n = p*q? */
98	r = BN_mul(i, key->p, key->q, ctx);
99	if (!r) { ret = -1; goto err; }
100
101	if (BN_cmp(i, key->n) != 0)
102		{
103		ret = 0;
104		RSAerr(RSA_F_RSA_CHECK_KEY, RSA_R_N_DOES_NOT_EQUAL_P_Q);
105		}
106
107	/* d*e = 1  mod lcm(p-1,q-1)? */
108
109	r = BN_sub(i, key->p, BN_value_one());
110	if (!r) { ret = -1; goto err; }
111	r = BN_sub(j, key->q, BN_value_one());
112	if (!r) { ret = -1; goto err; }
113
114	/* now compute k = lcm(i,j) */
115	r = BN_mul(l, i, j, ctx);
116	if (!r) { ret = -1; goto err; }
117	r = BN_gcd(m, i, j, ctx);
118	if (!r) { ret = -1; goto err; }
119	r = BN_div(k, NULL, l, m, ctx); /* remainder is 0 */
120	if (!r) { ret = -1; goto err; }
121
122	r = BN_mod_mul(i, key->d, key->e, k, ctx);
123	if (!r) { ret = -1; goto err; }
124
125	if (!BN_is_one(i))
126		{
127		ret = 0;
128		RSAerr(RSA_F_RSA_CHECK_KEY, RSA_R_D_E_NOT_CONGRUENT_TO_1);
129		}
130
131	if (key->dmp1 != NULL && key->dmq1 != NULL && key->iqmp != NULL)
132		{
133		/* dmp1 = d mod (p-1)? */
134		r = BN_sub(i, key->p, BN_value_one());
135		if (!r) { ret = -1; goto err; }
136
137		r = BN_mod(j, key->d, i, ctx);
138		if (!r) { ret = -1; goto err; }
139
140		if (BN_cmp(j, key->dmp1) != 0)
141			{
142			ret = 0;
143			RSAerr(RSA_F_RSA_CHECK_KEY,
144				RSA_R_DMP1_NOT_CONGRUENT_TO_D);
145			}
146
147		/* dmq1 = d mod (q-1)? */
148		r = BN_sub(i, key->q, BN_value_one());
149		if (!r) { ret = -1; goto err; }
150
151		r = BN_mod(j, key->d, i, ctx);
152		if (!r) { ret = -1; goto err; }
153
154		if (BN_cmp(j, key->dmq1) != 0)
155			{
156			ret = 0;
157			RSAerr(RSA_F_RSA_CHECK_KEY,
158				RSA_R_DMQ1_NOT_CONGRUENT_TO_D);
159			}
160
161		/* iqmp = q^-1 mod p? */
162		if(!BN_mod_inverse(i, key->q, key->p, ctx))
163			{
164			ret = -1;
165			goto err;
166			}
167
168		if (BN_cmp(i, key->iqmp) != 0)
169			{
170			ret = 0;
171			RSAerr(RSA_F_RSA_CHECK_KEY,
172				RSA_R_IQMP_NOT_INVERSE_OF_Q);
173			}
174		}
175
176 err:
177	if (i != NULL) BN_free(i);
178	if (j != NULL) BN_free(j);
179	if (k != NULL) BN_free(k);
180	if (l != NULL) BN_free(l);
181	if (m != NULL) BN_free(m);
182	if (ctx != NULL) BN_CTX_free(ctx);
183	return (ret);
184	}
185