1 /* crypto/rsa/rsa_lib.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 #include <stdio.h>
60 #include <openssl/crypto.h>
61 #include "cryptlib.h"
62 #include <openssl/lhash.h>
63 #include <openssl/bn.h>
64 #include <openssl/rsa.h>
65 #include <openssl/rand.h>
66 #ifndef OPENSSL_NO_ENGINE
67 #include <openssl/engine.h>
68 #endif
69
70 int RSA_size(const RSA *r)
71 {
72 return(BN_num_bytes(r->n));
73 }
74
75 int RSA_public_encrypt(int flen, const unsigned char *from, unsigned char *to,
76 RSA *rsa, int padding)
77 {
78 #ifdef OPENSSL_FIPS
79 if (FIPS_mode() && !(rsa->meth->flags & RSA_FLAG_FIPS_METHOD)
80 && !(rsa->flags & RSA_FLAG_NON_FIPS_ALLOW))
81 {
82 RSAerr(RSA_F_RSA_PUBLIC_ENCRYPT, RSA_R_NON_FIPS_RSA_METHOD);
83 return -1;
84 }
85 #endif
86 return(rsa->meth->rsa_pub_enc(flen, from, to, rsa, padding));
87 }
88
89 int RSA_private_encrypt(int flen, const unsigned char *from, unsigned char *to,
90 RSA *rsa, int padding)
91 {
92 #ifdef OPENSSL_FIPS
93 if (FIPS_mode() && !(rsa->meth->flags & RSA_FLAG_FIPS_METHOD)
94 && !(rsa->flags & RSA_FLAG_NON_FIPS_ALLOW))
95 {
96 RSAerr(RSA_F_RSA_PRIVATE_ENCRYPT, RSA_R_NON_FIPS_RSA_METHOD);
97 return -1;
98 }
99 #endif
100 return(rsa->meth->rsa_priv_enc(flen, from, to, rsa, padding));
101 }
102
103 int RSA_private_decrypt(int flen, const unsigned char *from, unsigned char *to,
104 RSA *rsa, int padding)
105 {
106 #ifdef OPENSSL_FIPS
107 if (FIPS_mode() && !(rsa->meth->flags & RSA_FLAG_FIPS_METHOD)
108 && !(rsa->flags & RSA_FLAG_NON_FIPS_ALLOW))
109 {
110 RSAerr(RSA_F_RSA_PRIVATE_DECRYPT, RSA_R_NON_FIPS_RSA_METHOD);
111 return -1;
112 }
113 #endif
114 return(rsa->meth->rsa_priv_dec(flen, from, to, rsa, padding));
115 }
116
117 int RSA_public_decrypt(int flen, const unsigned char *from, unsigned char *to,
118 RSA *rsa, int padding)
119 {
120 #ifdef OPENSSL_FIPS
121 if (FIPS_mode() && !(rsa->meth->flags & RSA_FLAG_FIPS_METHOD)
122 && !(rsa->flags & RSA_FLAG_NON_FIPS_ALLOW))
123 {
124 RSAerr(RSA_F_RSA_PUBLIC_DECRYPT, RSA_R_NON_FIPS_RSA_METHOD);
125 return -1;
126 }
127 #endif
128 return(rsa->meth->rsa_pub_dec(flen, from, to, rsa, padding));
129 }
130
131 int RSA_flags(const RSA *r)
132 {
133 return((r == NULL)?0:r->meth->flags);
134 }
135
136 void RSA_blinding_off(RSA *rsa)
137 {
138 if (rsa->blinding != NULL)
139 {
140 BN_BLINDING_free(rsa->blinding);
141 rsa->blinding=NULL;
142 }
143 rsa->flags &= ~RSA_FLAG_BLINDING;
144 rsa->flags |= RSA_FLAG_NO_BLINDING;
145 }
146
147 int RSA_blinding_on(RSA *rsa, BN_CTX *ctx)
148 {
149 int ret=0;
150
151 if (rsa->blinding != NULL)
152 RSA_blinding_off(rsa);
153
154 rsa->blinding = RSA_setup_blinding(rsa, ctx);
155 if (rsa->blinding == NULL)
156 goto err;
157
158 rsa->flags |= RSA_FLAG_BLINDING;
159 rsa->flags &= ~RSA_FLAG_NO_BLINDING;
160 ret=1;
161 err:
162 return(ret);
163 }
164
165 static BIGNUM *rsa_get_public_exp(const BIGNUM *d, const BIGNUM *p,
166 const BIGNUM *q, BN_CTX *ctx)
167 {
168 BIGNUM *ret = NULL, *r0, *r1, *r2;
169
170 if (d == NULL || p == NULL || q == NULL)
171 return NULL;
172
173 BN_CTX_start(ctx);
174 r0 = BN_CTX_get(ctx);
175 r1 = BN_CTX_get(ctx);
176 r2 = BN_CTX_get(ctx);
177 if (r2 == NULL)
178 goto err;
179
180 if (!BN_sub(r1, p, BN_value_one())) goto err;
181 if (!BN_sub(r2, q, BN_value_one())) goto err;
182 if (!BN_mul(r0, r1, r2, ctx)) goto err;
183
184 ret = BN_mod_inverse(NULL, d, r0, ctx);
185 err:
186 BN_CTX_end(ctx);
187 return ret;
188 }
189
190 BN_BLINDING *RSA_setup_blinding(RSA *rsa, BN_CTX *in_ctx)
191 {
192 BIGNUM local_n;
193 BIGNUM *e,*n;
194 BN_CTX *ctx;
195 BN_BLINDING *ret = NULL;
196
197 if (in_ctx == NULL)
198 {
199 if ((ctx = BN_CTX_new()) == NULL) return 0;
200 }
201 else
202 ctx = in_ctx;
203
204 BN_CTX_start(ctx);
205 e = BN_CTX_get(ctx);
206 if (e == NULL)
207 {
208 RSAerr(RSA_F_RSA_SETUP_BLINDING, ERR_R_MALLOC_FAILURE);
209 goto err;
210 }
211
212 if (rsa->e == NULL)
213 {
214 e = rsa_get_public_exp(rsa->d, rsa->p, rsa->q, ctx);
215 if (e == NULL)
216 {
217 RSAerr(RSA_F_RSA_SETUP_BLINDING, RSA_R_NO_PUBLIC_EXPONENT);
218 goto err;
219 }
220 }
221 else
222 e = rsa->e;
223
224
225 if ((RAND_status() == 0) && rsa->d != NULL && rsa->d->d != NULL)
226 {
227 /* if PRNG is not properly seeded, resort to secret
228 * exponent as unpredictable seed */
229 RAND_add(rsa->d->d, rsa->d->dmax * sizeof rsa->d->d[0], 0.0);
230 }
231
232 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
233 {
234 /* Set BN_FLG_CONSTTIME flag */
235 n = &local_n;
236 BN_with_flags(n, rsa->n, BN_FLG_CONSTTIME);
237 }
238 else
239 n = rsa->n;
240
241 ret = BN_BLINDING_create_param(NULL, e, n, ctx,
242 rsa->meth->bn_mod_exp, rsa->_method_mod_n);
243 if (ret == NULL)
244 {
245 RSAerr(RSA_F_RSA_SETUP_BLINDING, ERR_R_BN_LIB);
246 goto err;
247 }
248 CRYPTO_THREADID_current(BN_BLINDING_thread_id(ret));
249 err:
250 BN_CTX_end(ctx);
251 if (in_ctx == NULL)
252 BN_CTX_free(ctx);
253 if(rsa->e == NULL)
254 BN_free(e);
255
256 return ret;
257 }