rsa_lib.c revision 296465
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_public_encrypt(int flen, const unsigned char *from, unsigned char *to, 71 RSA *rsa, int padding) 72{ 73 return (rsa->meth->rsa_pub_enc(flen, from, to, rsa, padding)); 74} 75 76int RSA_private_encrypt(int flen, const unsigned char *from, 77 unsigned char *to, RSA *rsa, int padding) 78{ 79#ifdef OPENSSL_FIPS 80 if (FIPS_mode() && !(rsa->flags & RSA_FLAG_NON_FIPS_ALLOW)) { 81 RSAerr(RSA_F_RSA_PRIVATE_ENCRYPT, 82 RSA_R_OPERATION_NOT_ALLOWED_IN_FIPS_MODE); 83 return 0; 84 } 85#endif 86 return (rsa->meth->rsa_priv_enc(flen, from, to, rsa, padding)); 87} 88 89int RSA_private_decrypt(int flen, const unsigned char *from, 90 unsigned char *to, RSA *rsa, int padding) 91{ 92 return (rsa->meth->rsa_priv_dec(flen, from, to, rsa, padding)); 93} 94 95int RSA_public_decrypt(int flen, const unsigned char *from, unsigned char *to, 96 RSA *rsa, int padding) 97{ 98#ifdef OPENSSL_FIPS 99 if (FIPS_mode() && !(rsa->flags & RSA_FLAG_NON_FIPS_ALLOW)) { 100 RSAerr(RSA_F_RSA_PUBLIC_DECRYPT, 101 RSA_R_OPERATION_NOT_ALLOWED_IN_FIPS_MODE); 102 return 0; 103 } 104#endif 105 return (rsa->meth->rsa_pub_dec(flen, from, to, rsa, padding)); 106} 107 108int RSA_size(const RSA *r) 109{ 110 return (BN_num_bytes(r->n)); 111} 112 113void RSA_blinding_off(RSA *rsa) 114{ 115 if (rsa->blinding != NULL) { 116 BN_BLINDING_free(rsa->blinding); 117 rsa->blinding = NULL; 118 } 119 rsa->flags &= ~RSA_FLAG_BLINDING; 120 rsa->flags |= RSA_FLAG_NO_BLINDING; 121} 122 123int RSA_blinding_on(RSA *rsa, BN_CTX *ctx) 124{ 125 int ret = 0; 126 127 if (rsa->blinding != NULL) 128 RSA_blinding_off(rsa); 129 130 rsa->blinding = RSA_setup_blinding(rsa, ctx); 131 if (rsa->blinding == NULL) 132 goto err; 133 134 rsa->flags |= RSA_FLAG_BLINDING; 135 rsa->flags &= ~RSA_FLAG_NO_BLINDING; 136 ret = 1; 137 err: 138 return (ret); 139} 140 141static BIGNUM *rsa_get_public_exp(const BIGNUM *d, const BIGNUM *p, 142 const BIGNUM *q, BN_CTX *ctx) 143{ 144 BIGNUM *ret = NULL, *r0, *r1, *r2; 145 146 if (d == NULL || p == NULL || q == NULL) 147 return NULL; 148 149 BN_CTX_start(ctx); 150 r0 = BN_CTX_get(ctx); 151 r1 = BN_CTX_get(ctx); 152 r2 = BN_CTX_get(ctx); 153 if (r2 == NULL) 154 goto err; 155 156 if (!BN_sub(r1, p, BN_value_one())) 157 goto err; 158 if (!BN_sub(r2, q, BN_value_one())) 159 goto err; 160 if (!BN_mul(r0, r1, r2, ctx)) 161 goto err; 162 163 ret = BN_mod_inverse(NULL, d, r0, ctx); 164 err: 165 BN_CTX_end(ctx); 166 return ret; 167} 168 169BN_BLINDING *RSA_setup_blinding(RSA *rsa, BN_CTX *in_ctx) 170{ 171 BIGNUM local_n; 172 BIGNUM *e, *n; 173 BN_CTX *ctx; 174 BN_BLINDING *ret = NULL; 175 176 if (in_ctx == NULL) { 177 if ((ctx = BN_CTX_new()) == NULL) 178 return 0; 179 } else 180 ctx = in_ctx; 181 182 BN_CTX_start(ctx); 183 e = BN_CTX_get(ctx); 184 if (e == NULL) { 185 RSAerr(RSA_F_RSA_SETUP_BLINDING, ERR_R_MALLOC_FAILURE); 186 goto err; 187 } 188 189 if (rsa->e == NULL) { 190 e = rsa_get_public_exp(rsa->d, rsa->p, rsa->q, ctx); 191 if (e == NULL) { 192 RSAerr(RSA_F_RSA_SETUP_BLINDING, RSA_R_NO_PUBLIC_EXPONENT); 193 goto err; 194 } 195 } else 196 e = rsa->e; 197 198 if ((RAND_status() == 0) && rsa->d != NULL && rsa->d->d != NULL) { 199 /* 200 * if PRNG is not properly seeded, resort to secret exponent as 201 * unpredictable seed 202 */ 203 RAND_add(rsa->d->d, rsa->d->dmax * sizeof rsa->d->d[0], 0.0); 204 } 205 206 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) { 207 /* Set BN_FLG_CONSTTIME flag */ 208 n = &local_n; 209 BN_with_flags(n, rsa->n, BN_FLG_CONSTTIME); 210 } else 211 n = rsa->n; 212 213 ret = BN_BLINDING_create_param(NULL, e, n, ctx, 214 rsa->meth->bn_mod_exp, rsa->_method_mod_n); 215 if (ret == NULL) { 216 RSAerr(RSA_F_RSA_SETUP_BLINDING, ERR_R_BN_LIB); 217 goto err; 218 } 219 BN_BLINDING_set_thread_id(ret, CRYPTO_thread_id()); 220 err: 221 BN_CTX_end(ctx); 222 if (in_ctx == NULL) 223 BN_CTX_free(ctx); 224 if (rsa->e == NULL) 225 BN_free(e); 226 227 return ret; 228} 229