1 /* $OpenBSD: dh_lib.c,v 1.46 2024/11/29 15:59:57 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 #include "dh_local.h" 69 70 static const DH_METHOD *default_DH_method = NULL; 71 72 void 73 DH_set_default_method(const DH_METHOD *meth) 74 { 75 default_DH_method = meth; 76 } 77 LCRYPTO_ALIAS(DH_set_default_method); 78 79 const DH_METHOD * 80 DH_get_default_method(void) 81 { 82 if (!default_DH_method) 83 default_DH_method = DH_OpenSSL(); 84 return default_DH_method; 85 } 86 LCRYPTO_ALIAS(DH_get_default_method); 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 dh->meth = meth; 101 if (meth->init) 102 meth->init(dh); 103 return 1; 104 } 105 LCRYPTO_ALIAS(DH_set_method); 106 107 DH * 108 DH_new(void) 109 { 110 return DH_new_method(NULL); 111 } 112 LCRYPTO_ALIAS(DH_new); 113 114 DH * 115 DH_new_method(ENGINE *engine) 116 { 117 DH *dh; 118 119 if ((dh = calloc(1, sizeof(*dh))) == NULL) { 120 DHerror(ERR_R_MALLOC_FAILURE); 121 goto err; 122 } 123 124 dh->meth = DH_get_default_method(); 125 dh->flags = dh->meth->flags & ~DH_FLAG_NON_FIPS_ALLOW; 126 dh->references = 1; 127 128 if (!CRYPTO_new_ex_data(CRYPTO_EX_INDEX_DH, dh, &dh->ex_data)) 129 goto err; 130 if (dh->meth->init != NULL && !dh->meth->init(dh)) 131 goto err; 132 133 return dh; 134 135 err: 136 DH_free(dh); 137 138 return NULL; 139 } 140 LCRYPTO_ALIAS(DH_new_method); 141 142 void 143 DH_free(DH *dh) 144 { 145 if (dh == NULL) 146 return; 147 148 if (CRYPTO_add(&dh->references, -1, CRYPTO_LOCK_DH) > 0) 149 return; 150 151 if (dh->meth != NULL && dh->meth->finish != NULL) 152 dh->meth->finish(dh); 153 154 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DH, dh, &dh->ex_data); 155 156 BN_free(dh->p); 157 BN_free(dh->q); 158 BN_free(dh->g); 159 BN_free(dh->pub_key); 160 BN_free(dh->priv_key); 161 free(dh); 162 } 163 LCRYPTO_ALIAS(DH_free); 164 165 int 166 DH_up_ref(DH *dh) 167 { 168 return CRYPTO_add(&dh->references, 1, CRYPTO_LOCK_DH) > 1; 169 } 170 LCRYPTO_ALIAS(DH_up_ref); 171 172 int 173 DH_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func, 174 CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func) 175 { 176 return CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_DH, argl, argp, new_func, 177 dup_func, free_func); 178 } 179 LCRYPTO_ALIAS(DH_get_ex_new_index); 180 181 int 182 DH_set_ex_data(DH *dh, int idx, void *arg) 183 { 184 return CRYPTO_set_ex_data(&dh->ex_data, idx, arg); 185 } 186 LCRYPTO_ALIAS(DH_set_ex_data); 187 188 void * 189 DH_get_ex_data(DH *dh, int idx) 190 { 191 return CRYPTO_get_ex_data(&dh->ex_data, idx); 192 } 193 LCRYPTO_ALIAS(DH_get_ex_data); 194 195 int 196 DH_size(const DH *dh) 197 { 198 return BN_num_bytes(dh->p); 199 } 200 LCRYPTO_ALIAS(DH_size); 201 202 int 203 DH_bits(const DH *dh) 204 { 205 return BN_num_bits(dh->p); 206 } 207 LCRYPTO_ALIAS(DH_bits); 208 209 int 210 DH_security_bits(const DH *dh) 211 { 212 int N = -1; 213 214 if (dh->q != NULL) 215 N = BN_num_bits(dh->q); 216 else if (dh->length > 0) 217 N = dh->length; 218 219 return BN_security_bits(BN_num_bits(dh->p), N); 220 } 221 LCRYPTO_ALIAS(DH_security_bits); 222 223 ENGINE * 224 DH_get0_engine(DH *dh) 225 { 226 return NULL; 227 } 228 LCRYPTO_ALIAS(DH_get0_engine); 229 230 void 231 DH_get0_pqg(const DH *dh, const BIGNUM **p, const BIGNUM **q, const BIGNUM **g) 232 { 233 if (p != NULL) 234 *p = dh->p; 235 if (q != NULL) 236 *q = dh->q; 237 if (g != NULL) 238 *g = dh->g; 239 } 240 LCRYPTO_ALIAS(DH_get0_pqg); 241 242 int 243 DH_set0_pqg(DH *dh, BIGNUM *p, BIGNUM *q, BIGNUM *g) 244 { 245 if ((dh->p == NULL && p == NULL) || (dh->g == NULL && g == NULL)) 246 return 0; 247 248 if (p != NULL) { 249 BN_free(dh->p); 250 dh->p = p; 251 } 252 if (q != NULL) { 253 BN_free(dh->q); 254 dh->q = q; 255 dh->length = BN_num_bits(dh->q); 256 } 257 if (g != NULL) { 258 BN_free(dh->g); 259 dh->g = g; 260 } 261 262 return 1; 263 } 264 LCRYPTO_ALIAS(DH_set0_pqg); 265 266 void 267 DH_get0_key(const DH *dh, const BIGNUM **pub_key, const BIGNUM **priv_key) 268 { 269 if (pub_key != NULL) 270 *pub_key = dh->pub_key; 271 if (priv_key != NULL) 272 *priv_key = dh->priv_key; 273 } 274 LCRYPTO_ALIAS(DH_get0_key); 275 276 int 277 DH_set0_key(DH *dh, BIGNUM *pub_key, BIGNUM *priv_key) 278 { 279 if (pub_key != NULL) { 280 BN_free(dh->pub_key); 281 dh->pub_key = pub_key; 282 } 283 if (priv_key != NULL) { 284 BN_free(dh->priv_key); 285 dh->priv_key = priv_key; 286 } 287 288 return 1; 289 } 290 LCRYPTO_ALIAS(DH_set0_key); 291 292 const BIGNUM * 293 DH_get0_p(const DH *dh) 294 { 295 return dh->p; 296 } 297 LCRYPTO_ALIAS(DH_get0_p); 298 299 const BIGNUM * 300 DH_get0_q(const DH *dh) 301 { 302 return dh->q; 303 } 304 LCRYPTO_ALIAS(DH_get0_q); 305 306 const BIGNUM * 307 DH_get0_g(const DH *dh) 308 { 309 return dh->g; 310 } 311 LCRYPTO_ALIAS(DH_get0_g); 312 313 const BIGNUM * 314 DH_get0_priv_key(const DH *dh) 315 { 316 return dh->priv_key; 317 } 318 LCRYPTO_ALIAS(DH_get0_priv_key); 319 320 const BIGNUM * 321 DH_get0_pub_key(const DH *dh) 322 { 323 return dh->pub_key; 324 } 325 LCRYPTO_ALIAS(DH_get0_pub_key); 326 327 void 328 DH_clear_flags(DH *dh, int flags) 329 { 330 dh->flags &= ~flags; 331 } 332 LCRYPTO_ALIAS(DH_clear_flags); 333 334 int 335 DH_test_flags(const DH *dh, int flags) 336 { 337 return dh->flags & flags; 338 } 339 LCRYPTO_ALIAS(DH_test_flags); 340 341 void 342 DH_set_flags(DH *dh, int flags) 343 { 344 dh->flags |= flags; 345 } 346 LCRYPTO_ALIAS(DH_set_flags); 347 348 long 349 DH_get_length(const DH *dh) 350 { 351 return dh->length; 352 } 353 LCRYPTO_ALIAS(DH_get_length); 354 355 int 356 DH_set_length(DH *dh, long length) 357 { 358 if (length < 0 || length > INT_MAX) 359 return 0; 360 361 dh->length = length; 362 return 1; 363 } 364 LCRYPTO_ALIAS(DH_set_length); 365