1 /* $OpenBSD: dh_lib.c,v 1.32 2018/05/02 15:48:38 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 ENGINE_finish(dh->engine); 102 dh->engine = NULL; 103 #endif 104 dh->meth = meth; 105 if (meth->init) 106 meth->init(dh); 107 return 1; 108 } 109 110 DH * 111 DH_new(void) 112 { 113 return DH_new_method(NULL); 114 } 115 116 DH * 117 DH_new_method(ENGINE *engine) 118 { 119 DH *ret; 120 121 ret = malloc(sizeof(DH)); 122 if (ret == NULL) { 123 DHerror(ERR_R_MALLOC_FAILURE); 124 return NULL; 125 } 126 127 ret->meth = DH_get_default_method(); 128 #ifndef OPENSSL_NO_ENGINE 129 if (engine) { 130 if (!ENGINE_init(engine)) { 131 DHerror(ERR_R_ENGINE_LIB); 132 free(ret); 133 return NULL; 134 } 135 ret->engine = engine; 136 } else 137 ret->engine = ENGINE_get_default_DH(); 138 if(ret->engine) { 139 ret->meth = ENGINE_get_DH(ret->engine); 140 if (ret->meth == NULL) { 141 DHerror(ERR_R_ENGINE_LIB); 142 ENGINE_finish(ret->engine); 143 free(ret); 144 return NULL; 145 } 146 } 147 #endif 148 149 ret->pad = 0; 150 ret->version = 0; 151 ret->p = NULL; 152 ret->g = NULL; 153 ret->length = 0; 154 ret->pub_key = NULL; 155 ret->priv_key = NULL; 156 ret->q = NULL; 157 ret->j = NULL; 158 ret->seed = NULL; 159 ret->seedlen = 0; 160 ret->counter = NULL; 161 ret->method_mont_p=NULL; 162 ret->references = 1; 163 ret->flags = ret->meth->flags & ~DH_FLAG_NON_FIPS_ALLOW; 164 CRYPTO_new_ex_data(CRYPTO_EX_INDEX_DH, ret, &ret->ex_data); 165 if (ret->meth->init != NULL && !ret->meth->init(ret)) { 166 #ifndef OPENSSL_NO_ENGINE 167 ENGINE_finish(ret->engine); 168 #endif 169 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DH, ret, &ret->ex_data); 170 free(ret); 171 ret = NULL; 172 } 173 return ret; 174 } 175 176 void 177 DH_free(DH *r) 178 { 179 int i; 180 181 if (r == NULL) 182 return; 183 i = CRYPTO_add(&r->references, -1, CRYPTO_LOCK_DH); 184 if (i > 0) 185 return; 186 187 if (r->meth->finish) 188 r->meth->finish(r); 189 #ifndef OPENSSL_NO_ENGINE 190 ENGINE_finish(r->engine); 191 #endif 192 193 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DH, r, &r->ex_data); 194 195 BN_clear_free(r->p); 196 BN_clear_free(r->g); 197 BN_clear_free(r->q); 198 BN_clear_free(r->j); 199 free(r->seed); 200 BN_clear_free(r->counter); 201 BN_clear_free(r->pub_key); 202 BN_clear_free(r->priv_key); 203 free(r); 204 } 205 206 int 207 DH_up_ref(DH *r) 208 { 209 int i = CRYPTO_add(&r->references, 1, CRYPTO_LOCK_DH); 210 211 return i > 1 ? 1 : 0; 212 } 213 214 int 215 DH_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func, 216 CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func) 217 { 218 return CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_DH, argl, argp, new_func, 219 dup_func, free_func); 220 } 221 222 int 223 DH_set_ex_data(DH *d, int idx, void *arg) 224 { 225 return CRYPTO_set_ex_data(&d->ex_data, idx, arg); 226 } 227 228 void * 229 DH_get_ex_data(DH *d, int idx) 230 { 231 return CRYPTO_get_ex_data(&d->ex_data, idx); 232 } 233 234 int 235 DH_size(const DH *dh) 236 { 237 return BN_num_bytes(dh->p); 238 } 239 240 int 241 DH_bits(const DH *dh) 242 { 243 return BN_num_bits(dh->p); 244 } 245 246 ENGINE * 247 DH_get0_engine(DH *dh) 248 { 249 return dh->engine; 250 } 251 252 void 253 DH_get0_pqg(const DH *dh, const BIGNUM **p, const BIGNUM **q, const BIGNUM **g) 254 { 255 if (p != NULL) 256 *p = dh->p; 257 if (q != NULL) 258 *q = dh->q; 259 if (g != NULL) 260 *g = dh->g; 261 } 262 263 int 264 DH_set0_pqg(DH *dh, BIGNUM *p, BIGNUM *q, BIGNUM *g) 265 { 266 if ((dh->p == NULL && p == NULL) || (dh->g == NULL && g == NULL)) 267 return 0; 268 269 if (p != NULL) { 270 BN_free(dh->p); 271 dh->p = p; 272 } 273 if (q != NULL) { 274 BN_free(dh->q); 275 dh->q = q; 276 } 277 if (g != NULL) { 278 BN_free(dh->g); 279 dh->g = g; 280 } 281 282 return 1; 283 } 284 285 void 286 DH_get0_key(const DH *dh, const BIGNUM **pub_key, const BIGNUM **priv_key) 287 { 288 if (pub_key != NULL) 289 *pub_key = dh->pub_key; 290 if (priv_key != NULL) 291 *priv_key = dh->priv_key; 292 } 293 294 int 295 DH_set0_key(DH *dh, BIGNUM *pub_key, BIGNUM *priv_key) 296 { 297 if (pub_key != NULL) { 298 BN_free(dh->pub_key); 299 dh->pub_key = pub_key; 300 } 301 if (priv_key != NULL) { 302 BN_free(dh->priv_key); 303 dh->priv_key = priv_key; 304 } 305 306 return 1; 307 } 308 309 void 310 DH_clear_flags(DH *dh, int flags) 311 { 312 dh->flags &= ~flags; 313 } 314 315 int 316 DH_test_flags(const DH *dh, int flags) 317 { 318 return dh->flags & flags; 319 } 320 321 void 322 DH_set_flags(DH *dh, int flags) 323 { 324 dh->flags |= flags; 325 } 326 327 int 328 DH_set_length(DH *dh, long length) 329 { 330 if (length < 0 || length > INT_MAX) 331 return 0; 332 333 dh->length = length; 334 return 1; 335 } 336