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