1 /* crypto/rsa/rsa_lib.c */ 2 /* Copyright (C) 1995-1998 Eric Young (eay (at) cryptsoft.com) 3 * All rights reserved. 4 * 5 * This package is an SSL implementation written 6 * by Eric Young (eay (at) 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 (at) 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 (at) 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 (at) 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 } 258