1 /* $OpenBSD: dh_lib.c,v 1.29 2018/02/20 21:11:15 tb Exp $ */ 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 <limits.h> 60 #include <stdio.h> 61 62 #include <openssl/opensslconf.h> 63 64 #include <openssl/bn.h> 65 #include <openssl/dh.h> 66 #include <openssl/err.h> 67 68 #ifndef OPENSSL_NO_ENGINE 69 #include <openssl/engine.h> 70 #endif 71 72 static const DH_METHOD *default_DH_method = NULL; 73 74 void 75 DH_set_default_method(const DH_METHOD *meth) 76 { 77 default_DH_method = meth; 78 } 79 80 const DH_METHOD * 81 DH_get_default_method(void) 82 { 83 if (!default_DH_method) 84 default_DH_method = DH_OpenSSL(); 85 return default_DH_method; 86 } 87 88 int 89 DH_set_method(DH *dh, const DH_METHOD *meth) 90 { 91 /* 92 * NB: The caller is specifically setting a method, so it's not up to us 93 * to deal with which ENGINE it comes from. 94 */ 95 const DH_METHOD *mtmp; 96 97 mtmp = dh->meth; 98 if (mtmp->finish) 99 mtmp->finish(dh); 100 #ifndef OPENSSL_NO_ENGINE 101 if (dh->engine) { 102 ENGINE_finish(dh->engine); 103 dh->engine = NULL; 104 } 105 #endif 106 dh->meth = meth; 107 if (meth->init) 108 meth->init(dh); 109 return 1; 110 } 111 112 DH * 113 DH_new(void) 114 { 115 return DH_new_method(NULL); 116 } 117 118 DH * 119 DH_new_method(ENGINE *engine) 120 { 121 DH *ret; 122 123 ret = malloc(sizeof(DH)); 124 if (ret == NULL) { 125 DHerror(ERR_R_MALLOC_FAILURE); 126 return NULL; 127 } 128 129 ret->meth = DH_get_default_method(); 130 #ifndef OPENSSL_NO_ENGINE 131 if (engine) { 132 if (!ENGINE_init(engine)) { 133 DHerror(ERR_R_ENGINE_LIB); 134 free(ret); 135 return NULL; 136 } 137 ret->engine = engine; 138 } else 139 ret->engine = ENGINE_get_default_DH(); 140 if(ret->engine) { 141 ret->meth = ENGINE_get_DH(ret->engine); 142 if (!ret->meth) { 143 DHerror(ERR_R_ENGINE_LIB); 144 ENGINE_finish(ret->engine); 145 free(ret); 146 return NULL; 147 } 148 } 149 #endif 150 151 ret->pad = 0; 152 ret->version = 0; 153 ret->p = NULL; 154 ret->g = NULL; 155 ret->length = 0; 156 ret->pub_key = NULL; 157 ret->priv_key = NULL; 158 ret->q = NULL; 159 ret->j = NULL; 160 ret->seed = NULL; 161 ret->seedlen = 0; 162 ret->counter = NULL; 163 ret->method_mont_p=NULL; 164 ret->references = 1; 165 ret->flags = ret->meth->flags & ~DH_FLAG_NON_FIPS_ALLOW; 166 CRYPTO_new_ex_data(CRYPTO_EX_INDEX_DH, ret, &ret->ex_data); 167 if (ret->meth->init != NULL && !ret->meth->init(ret)) { 168 #ifndef OPENSSL_NO_ENGINE 169 if (ret->engine) 170 ENGINE_finish(ret->engine); 171 #endif 172 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DH, ret, &ret->ex_data); 173 free(ret); 174 ret = NULL; 175 } 176 return ret; 177 } 178 179 void 180 DH_free(DH *r) 181 { 182 int i; 183 184 if (r == NULL) 185 return; 186 i = CRYPTO_add(&r->references, -1, CRYPTO_LOCK_DH); 187 if (i > 0) 188 return; 189 190 if (r->meth->finish) 191 r->meth->finish(r); 192 #ifndef OPENSSL_NO_ENGINE 193 if (r->engine) 194 ENGINE_finish(r->engine); 195 #endif 196 197 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DH, r, &r->ex_data); 198 199 BN_clear_free(r->p); 200 BN_clear_free(r->g); 201 BN_clear_free(r->q); 202 BN_clear_free(r->j); 203 free(r->seed); 204 BN_clear_free(r->counter); 205 BN_clear_free(r->pub_key); 206 BN_clear_free(r->priv_key); 207 free(r); 208 } 209 210 int 211 DH_up_ref(DH *r) 212 { 213 int i = CRYPTO_add(&r->references, 1, CRYPTO_LOCK_DH); 214 215 return i > 1 ? 1 : 0; 216 } 217 218 int 219 DH_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func, 220 CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func) 221 { 222 return CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_DH, argl, argp, new_func, 223 dup_func, free_func); 224 } 225 226 int 227 DH_set_ex_data(DH *d, int idx, void *arg) 228 { 229 return CRYPTO_set_ex_data(&d->ex_data, idx, arg); 230 } 231 232 void * 233 DH_get_ex_data(DH *d, int idx) 234 { 235 return CRYPTO_get_ex_data(&d->ex_data, idx); 236 } 237 238 int 239 DH_size(const DH *dh) 240 { 241 return BN_num_bytes(dh->p); 242 } 243 244 int 245 DH_bits(const DH *dh) 246 { 247 return BN_num_bits(dh->p); 248 } 249 250 void 251 DH_get0_pqg(const DH *dh, const BIGNUM **p, const BIGNUM **q, const BIGNUM **g) 252 { 253 if (p != NULL) 254 *p = dh->p; 255 if (q != NULL) 256 *q = dh->q; 257 if (g != NULL) 258 *g = dh->g; 259 } 260 261 int 262 DH_set0_pqg(DH *dh, BIGNUM *p, BIGNUM *q, BIGNUM *g) 263 { 264 if ((dh->p == NULL && p == NULL) || (dh->g == NULL && g == NULL)) 265 return 0; 266 267 if (p != NULL) { 268 BN_free(dh->p); 269 dh->p = p; 270 } 271 if (q != NULL) { 272 BN_free(dh->q); 273 dh->q = q; 274 } 275 if (g != NULL) { 276 BN_free(dh->g); 277 dh->g = g; 278 } 279 280 return 1; 281 } 282 283 void 284 DH_get0_key(const DH *dh, const BIGNUM **pub_key, const BIGNUM **priv_key) 285 { 286 if (pub_key != NULL) 287 *pub_key = dh->pub_key; 288 if (priv_key != NULL) 289 *priv_key = dh->priv_key; 290 } 291 292 int 293 DH_set0_key(DH *dh, BIGNUM *pub_key, BIGNUM *priv_key) 294 { 295 if ((dh->pub_key == NULL && pub_key == NULL) || 296 (dh->priv_key == NULL && priv_key == NULL)) 297 return 0; 298 299 if (pub_key != NULL) { 300 BN_free(dh->pub_key); 301 dh->pub_key = pub_key; 302 } 303 if (priv_key != NULL) { 304 BN_free(dh->priv_key); 305 dh->priv_key = priv_key; 306 } 307 308 return 1; 309 } 310 311 void 312 DH_clear_flags(DH *dh, int flags) 313 { 314 dh->flags &= ~flags; 315 } 316 317 int 318 DH_test_flags(const DH *dh, int flags) 319 { 320 return dh->flags & flags; 321 } 322 323 void 324 DH_set_flags(DH *dh, int flags) 325 { 326 dh->flags |= flags; 327 } 328 329 int 330 DH_set_length(DH *dh, long length) 331 { 332 if (length < 0 || length > INT_MAX) 333 return 0; 334 335 dh->length = length; 336 return 1; 337 } 338