1 /* $OpenBSD: dh_lib.c,v 1.37 2022/06/27 12:31:38 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 #include "dh_local.h" 73 74 static const DH_METHOD *default_DH_method = NULL; 75 76 void 77 DH_set_default_method(const DH_METHOD *meth) 78 { 79 default_DH_method = meth; 80 } 81 82 const DH_METHOD * 83 DH_get_default_method(void) 84 { 85 if (!default_DH_method) 86 default_DH_method = DH_OpenSSL(); 87 return default_DH_method; 88 } 89 90 int 91 DH_set_method(DH *dh, const DH_METHOD *meth) 92 { 93 /* 94 * NB: The caller is specifically setting a method, so it's not up to us 95 * to deal with which ENGINE it comes from. 96 */ 97 const DH_METHOD *mtmp; 98 99 mtmp = dh->meth; 100 if (mtmp->finish) 101 mtmp->finish(dh); 102 #ifndef OPENSSL_NO_ENGINE 103 ENGINE_finish(dh->engine); 104 dh->engine = NULL; 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 == NULL) { 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 ENGINE_finish(ret->engine); 170 #endif 171 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DH, ret, &ret->ex_data); 172 free(ret); 173 ret = NULL; 174 } 175 return ret; 176 } 177 178 void 179 DH_free(DH *r) 180 { 181 int i; 182 183 if (r == NULL) 184 return; 185 i = CRYPTO_add(&r->references, -1, CRYPTO_LOCK_DH); 186 if (i > 0) 187 return; 188 189 if (r->meth->finish) 190 r->meth->finish(r); 191 #ifndef OPENSSL_NO_ENGINE 192 ENGINE_finish(r->engine); 193 #endif 194 195 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DH, r, &r->ex_data); 196 197 BN_clear_free(r->p); 198 BN_clear_free(r->g); 199 BN_clear_free(r->q); 200 BN_clear_free(r->j); 201 free(r->seed); 202 BN_clear_free(r->counter); 203 BN_clear_free(r->pub_key); 204 BN_clear_free(r->priv_key); 205 free(r); 206 } 207 208 int 209 DH_up_ref(DH *r) 210 { 211 int i = CRYPTO_add(&r->references, 1, CRYPTO_LOCK_DH); 212 213 return i > 1 ? 1 : 0; 214 } 215 216 int 217 DH_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func, 218 CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func) 219 { 220 return CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_DH, argl, argp, new_func, 221 dup_func, free_func); 222 } 223 224 int 225 DH_set_ex_data(DH *d, int idx, void *arg) 226 { 227 return CRYPTO_set_ex_data(&d->ex_data, idx, arg); 228 } 229 230 void * 231 DH_get_ex_data(DH *d, int idx) 232 { 233 return CRYPTO_get_ex_data(&d->ex_data, idx); 234 } 235 236 int 237 DH_size(const DH *dh) 238 { 239 return BN_num_bytes(dh->p); 240 } 241 242 int 243 DH_bits(const DH *dh) 244 { 245 return BN_num_bits(dh->p); 246 } 247 248 int 249 DH_security_bits(const DH *dh) 250 { 251 int N = -1; 252 253 if (dh->q != NULL) 254 N = BN_num_bits(dh->q); 255 else if (dh->length > 0) 256 N = dh->length; 257 258 return BN_security_bits(BN_num_bits(dh->p), N); 259 } 260 261 ENGINE * 262 DH_get0_engine(DH *dh) 263 { 264 return dh->engine; 265 } 266 267 void 268 DH_get0_pqg(const DH *dh, const BIGNUM **p, const BIGNUM **q, const BIGNUM **g) 269 { 270 if (p != NULL) 271 *p = dh->p; 272 if (q != NULL) 273 *q = dh->q; 274 if (g != NULL) 275 *g = dh->g; 276 } 277 278 int 279 DH_set0_pqg(DH *dh, BIGNUM *p, BIGNUM *q, BIGNUM *g) 280 { 281 if ((dh->p == NULL && p == NULL) || (dh->g == NULL && g == NULL)) 282 return 0; 283 284 if (p != NULL) { 285 BN_free(dh->p); 286 dh->p = p; 287 } 288 if (q != NULL) { 289 BN_free(dh->q); 290 dh->q = q; 291 dh->length = BN_num_bits(dh->q); 292 } 293 if (g != NULL) { 294 BN_free(dh->g); 295 dh->g = g; 296 } 297 298 return 1; 299 } 300 301 void 302 DH_get0_key(const DH *dh, const BIGNUM **pub_key, const BIGNUM **priv_key) 303 { 304 if (pub_key != NULL) 305 *pub_key = dh->pub_key; 306 if (priv_key != NULL) 307 *priv_key = dh->priv_key; 308 } 309 310 int 311 DH_set0_key(DH *dh, BIGNUM *pub_key, BIGNUM *priv_key) 312 { 313 if (pub_key != NULL) { 314 BN_free(dh->pub_key); 315 dh->pub_key = pub_key; 316 } 317 if (priv_key != NULL) { 318 BN_free(dh->priv_key); 319 dh->priv_key = priv_key; 320 } 321 322 return 1; 323 } 324 325 const BIGNUM * 326 DH_get0_p(const DH *dh) 327 { 328 return dh->p; 329 } 330 331 const BIGNUM * 332 DH_get0_q(const DH *dh) 333 { 334 return dh->q; 335 } 336 337 const BIGNUM * 338 DH_get0_g(const DH *dh) 339 { 340 return dh->g; 341 } 342 343 const BIGNUM * 344 DH_get0_priv_key(const DH *dh) 345 { 346 return dh->priv_key; 347 } 348 349 const BIGNUM * 350 DH_get0_pub_key(const DH *dh) 351 { 352 return dh->pub_key; 353 } 354 355 void 356 DH_clear_flags(DH *dh, int flags) 357 { 358 dh->flags &= ~flags; 359 } 360 361 int 362 DH_test_flags(const DH *dh, int flags) 363 { 364 return dh->flags & flags; 365 } 366 367 void 368 DH_set_flags(DH *dh, int flags) 369 { 370 dh->flags |= flags; 371 } 372 373 long 374 DH_get_length(const DH *dh) 375 { 376 return dh->length; 377 } 378 379 int 380 DH_set_length(DH *dh, long length) 381 { 382 if (length < 0 || length > INT_MAX) 383 return 0; 384 385 dh->length = length; 386 return 1; 387 } 388