1 /* Copyright (C) 1995-1998 Eric Young (eay (at) cryptsoft.com) 2 * All rights reserved. 3 * 4 * This package is an SSL implementation written 5 * by Eric Young (eay (at) cryptsoft.com). 6 * The implementation was written so as to conform with Netscapes SSL. 7 * 8 * This library is free for commercial and non-commercial use as long as 9 * the following conditions are aheared to. The following conditions 10 * apply to all code found in this distribution, be it the RC4, RSA, 11 * lhash, DES, etc., code; not just the SSL code. The SSL documentation 12 * included with this distribution is covered by the same copyright terms 13 * except that the holder is Tim Hudson (tjh (at) cryptsoft.com). 14 * 15 * Copyright remains Eric Young's, and as such any Copyright notices in 16 * the code are not to be removed. 17 * If this package is used in a product, Eric Young should be given attribution 18 * as the author of the parts of the library used. 19 * This can be in the form of a textual message at program startup or 20 * in documentation (online or textual) provided with the package. 21 * 22 * Redistribution and use in source and binary forms, with or without 23 * modification, are permitted provided that the following conditions 24 * are met: 25 * 1. Redistributions of source code must retain the copyright 26 * notice, this list of conditions and the following disclaimer. 27 * 2. Redistributions in binary form must reproduce the above copyright 28 * notice, this list of conditions and the following disclaimer in the 29 * documentation and/or other materials provided with the distribution. 30 * 3. All advertising materials mentioning features or use of this software 31 * must display the following acknowledgement: 32 * "This product includes cryptographic software written by 33 * Eric Young (eay (at) cryptsoft.com)" 34 * The word 'cryptographic' can be left out if the rouines from the library 35 * being used are not cryptographic related :-). 36 * 4. If you include any Windows specific code (or a derivative thereof) from 37 * the apps directory (application code) you must include an acknowledgement: 38 * "This product includes software written by Tim Hudson (tjh (at) cryptsoft.com)" 39 * 40 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 41 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 43 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 44 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 45 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 46 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 48 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 49 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 50 * SUCH DAMAGE. 51 * 52 * The licence and distribution terms for any publically available version or 53 * derivative of this code cannot be changed. i.e. this code cannot simply be 54 * copied and put under another distribution licence 55 * [including the GNU Public Licence.] */ 56 57 #include <openssl/dh.h> 58 59 #include <openssl/bn.h> 60 #include <openssl/buf.h> 61 #include <openssl/err.h> 62 #include <openssl/ex_data.h> 63 #include <openssl/mem.h> 64 #include <openssl/thread.h> 65 66 #include "internal.h" 67 68 69 extern const DH_METHOD DH_default_method; 70 71 DH *DH_new(void) { return DH_new_method(NULL); } 72 73 DH *DH_new_method(const ENGINE *engine) { 74 DH *dh = (DH *)OPENSSL_malloc(sizeof(DH)); 75 if (dh == NULL) { 76 OPENSSL_PUT_ERROR(DH, DH_new_method, ERR_R_MALLOC_FAILURE); 77 return NULL; 78 } 79 80 memset(dh, 0, sizeof(DH)); 81 82 if (engine) { 83 dh->meth = ENGINE_get_DH_method(engine); 84 } 85 86 if (dh->meth == NULL) { 87 dh->meth = (DH_METHOD*) &DH_default_method; 88 } 89 METHOD_ref(dh->meth); 90 91 dh->references = 1; 92 if (!CRYPTO_new_ex_data(CRYPTO_EX_INDEX_DH, dh, &dh->ex_data)) { 93 OPENSSL_free(dh); 94 return NULL; 95 } 96 97 if (dh->meth->init && !dh->meth->init(dh)) { 98 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DH, dh, &dh->ex_data); 99 METHOD_unref(dh->meth); 100 OPENSSL_free(dh); 101 return NULL; 102 } 103 104 return dh; 105 } 106 107 void DH_free(DH *dh) { 108 if (dh == NULL) { 109 return; 110 } 111 112 if (CRYPTO_add(&dh->references, -1, CRYPTO_LOCK_DH) > 0) { 113 return; 114 } 115 116 if (dh->meth->finish) { 117 dh->meth->finish(dh); 118 } 119 METHOD_unref(dh->meth); 120 121 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DH, dh, &dh->ex_data); 122 123 if (dh->method_mont_p) BN_MONT_CTX_free(dh->method_mont_p); 124 if (dh->p != NULL) BN_clear_free(dh->p); 125 if (dh->g != NULL) BN_clear_free(dh->g); 126 if (dh->q != NULL) BN_clear_free(dh->q); 127 if (dh->j != NULL) BN_clear_free(dh->j); 128 if (dh->seed) OPENSSL_free(dh->seed); 129 if (dh->counter != NULL) BN_clear_free(dh->counter); 130 if (dh->pub_key != NULL) BN_clear_free(dh->pub_key); 131 if (dh->priv_key != NULL) BN_clear_free(dh->priv_key); 132 133 OPENSSL_free(dh); 134 } 135 136 int DH_generate_parameters_ex(DH *dh, int prime_bits, int generator, BN_GENCB *cb) { 137 if (dh->meth->generate_parameters) { 138 return dh->meth->generate_parameters(dh, prime_bits, generator, cb); 139 } 140 return DH_default_method.generate_parameters(dh, prime_bits, generator, cb); 141 } 142 143 int DH_generate_key(DH *dh) { 144 if (dh->meth->generate_key) { 145 return dh->meth->generate_key(dh); 146 } 147 return DH_default_method.generate_key(dh); 148 } 149 150 int DH_compute_key(unsigned char *out, const BIGNUM *peers_key, DH *dh) { 151 if (dh->meth->compute_key) { 152 return dh->meth->compute_key(dh, out, peers_key); 153 } 154 return DH_default_method.compute_key(dh, out, peers_key); 155 } 156 157 int DH_size(const DH *dh) { return BN_num_bytes(dh->p); } 158 159 int DH_up_ref(DH *r) { 160 CRYPTO_add(&r->references, 1, CRYPTO_LOCK_DH); 161 return 1; 162 } 163 164 static int int_dh_bn_cpy(BIGNUM **dst, const BIGNUM *src) { 165 BIGNUM *a = NULL; 166 167 if (src) { 168 a = BN_dup(src); 169 if (!a) { 170 return 0; 171 } 172 } 173 174 if (*dst) { 175 BN_free(*dst); 176 } 177 *dst = a; 178 return 1; 179 } 180 181 static int int_dh_param_copy(DH *to, const DH *from, int is_x942) { 182 if (is_x942 == -1) { 183 is_x942 = !!from->q; 184 } 185 if (!int_dh_bn_cpy(&to->p, from->p) || 186 !int_dh_bn_cpy(&to->g, from->g)) { 187 return 0; 188 } 189 190 if (!is_x942) { 191 return 1; 192 } 193 194 if (!int_dh_bn_cpy(&to->q, from->q) || 195 !int_dh_bn_cpy(&to->j, from->j)) { 196 return 0; 197 } 198 199 if (to->seed) { 200 OPENSSL_free(to->seed); 201 to->seed = NULL; 202 to->seedlen = 0; 203 } 204 if (from->seed) { 205 to->seed = BUF_memdup(from->seed, from->seedlen); 206 if (!to->seed) { 207 return 0; 208 } 209 to->seedlen = from->seedlen; 210 } 211 212 return 1; 213 } 214 215 DH *DHparams_dup(const DH *dh) { 216 DH *ret = DH_new(); 217 if (!ret) { 218 return NULL; 219 } 220 221 if (!int_dh_param_copy(ret, dh, -1)) { 222 DH_free(ret); 223 return NULL; 224 } 225 226 return ret; 227 } 228 229 int DH_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func, 230 CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func) { 231 return CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_DH, argl, argp, new_func, 232 dup_func, free_func); 233 } 234 235 int DH_set_ex_data(DH *d, int idx, void *arg) { 236 return (CRYPTO_set_ex_data(&d->ex_data, idx, arg)); 237 } 238 239 void *DH_get_ex_data(DH *d, int idx) { 240 return (CRYPTO_get_ex_data(&d->ex_data, idx)); 241 } 242