crypto/dh/dh_lib.c

   1 /* crypto/dh/dh_lib.c */
   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 <stdio.h>
  60 #include "cryptlib.h"
  61 #include <openssl/bn.h>
  62 #include <openssl/dh.h>
  63 #ifndef OPENSSL_NO_ENGINE
  64 # include <openssl/engine.h>
  65 #endif
  66
  67 const char DH_version[] = "Diffie-Hellman" OPENSSL_VERSION_PTEXT;
  68
  69 static const DH_METHOD *default_DH_method = NULL;
  70
  71 void DH_set_default_method(const DH_METHOD *meth)
  72 {
  73     default_DH_method = meth;
  74 }
  75
  76 const DH_METHOD *DH_get_default_method(void)
  77 {
  78     if (!default_DH_method)
  79         default_DH_method = DH_OpenSSL();
  80     return default_DH_method;
  81 }
  82
  83 int DH_set_method(DH *dh, const DH_METHOD *meth)
  84 {
  85     /*
  86      * NB: The caller is specifically setting a method, so it's not up to us
  87      * to deal with which ENGINE it comes from.
  88      */
  89     const DH_METHOD *mtmp;
  90     mtmp = dh->meth;
  91     if (mtmp->finish)
  92         mtmp->finish(dh);
  93 #ifndef OPENSSL_NO_ENGINE
  94     if (dh->engine) {
  95         ENGINE_finish(dh->engine);
  96         dh->engine = NULL;
  97     }
  98 #endif
  99     dh->meth = meth;
 100     if (meth->init)
 101         meth->init(dh);
 102     return 1;
 103 }
 104
 105 DH *DH_new(void)
 106 {
 107     return DH_new_method(NULL);
 108 }
 109
 110 DH *DH_new_method(ENGINE *engine)
 111 {
 112     DH *ret;
 113
 114     ret = (DH *)OPENSSL_malloc(sizeof(DH));
 115     if (ret == NULL) {
 116         DHerr(DH_F_DH_NEW_METHOD, ERR_R_MALLOC_FAILURE);
 117         return (NULL);
 118     }
 119
 120     ret->meth = DH_get_default_method();
 121 #ifndef OPENSSL_NO_ENGINE
 122     if (engine) {
 123         if (!ENGINE_init(engine)) {
 124             DHerr(DH_F_DH_NEW_METHOD, ERR_R_ENGINE_LIB);
 125             OPENSSL_free(ret);
 126             return NULL;
 127         }
 128         ret->engine = engine;
 129     } else
 130         ret->engine = ENGINE_get_default_DH();
 131     if (ret->engine) {
 132         ret->meth = ENGINE_get_DH(ret->engine);
 133         if (!ret->meth) {
 134             DHerr(DH_F_DH_NEW_METHOD, ERR_R_ENGINE_LIB);
 135             ENGINE_finish(ret->engine);
 136             OPENSSL_free(ret);
 137             return NULL;
 138         }
 139     }
 140 #endif
 141
 142     ret->pad = 0;
 143     ret->version = 0;
 144     ret->p = NULL;
 145     ret->g = NULL;
 146     ret->length = 0;
 147     ret->pub_key = NULL;
 148     ret->priv_key = NULL;
 149     ret->q = NULL;
 150     ret->j = NULL;
 151     ret->seed = NULL;
 152     ret->seedlen = 0;
 153     ret->counter = NULL;
 154     ret->method_mont_p = NULL;
 155     ret->references = 1;
 156     ret->flags = ret->meth->flags;
 157     CRYPTO_new_ex_data(CRYPTO_EX_INDEX_DH, ret, &ret->ex_data);
 158     if ((ret->meth->init != NULL) && !ret->meth->init(ret)) {
 159 #ifndef OPENSSL_NO_ENGINE
 160         if (ret->engine)
 161             ENGINE_finish(ret->engine);
 162 #endif
 163         CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DH, ret, &ret->ex_data);
 164         OPENSSL_free(ret);
 165         ret = NULL;
 166     }
 167     return (ret);
 168 }
 169
 170 void DH_free(DH *r)
 171 {
 172     int i;
 173     if (r == NULL)
 174         return;
 175     i = CRYPTO_add(&r->references, -1, CRYPTO_LOCK_DH);
 176 #ifdef REF_PRINT
 177     REF_PRINT("DH", r);
 178 #endif
 179     if (i > 0)
 180         return;
 181 #ifdef REF_CHECK
 182     if (i < 0) {
 183         fprintf(stderr, "DH_free, bad reference count\n");
 184         abort();
 185     }
 186 #endif
 187
 188     if (r->meth->finish)
 189         r->meth->finish(r);
 190 #ifndef OPENSSL_NO_ENGINE
 191     if (r->engine)
 192         ENGINE_finish(r->engine);
 193 #endif
 194
 195     CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DH, r, &r->ex_data);
 196
 197     if (r->p != NULL)
 198         BN_clear_free(r->p);
 199     if (r->g != NULL)
 200         BN_clear_free(r->g);
 201     if (r->q != NULL)
 202         BN_clear_free(r->q);
 203     if (r->j != NULL)
 204         BN_clear_free(r->j);
 205     if (r->seed)
 206         OPENSSL_free(r->seed);
 207     if (r->counter != NULL)
 208         BN_clear_free(r->counter);
 209     if (r->pub_key != NULL)
 210         BN_clear_free(r->pub_key);
 211     if (r->priv_key != NULL)
 212         BN_clear_free(r->priv_key);
 213     OPENSSL_free(r);
 214 }
 215
 216 int DH_up_ref(DH *r)
 217 {
 218     int i = CRYPTO_add(&r->references, 1, CRYPTO_LOCK_DH);
 219 #ifdef REF_PRINT
 220     REF_PRINT("DH", r);
 221 #endif
 222 #ifdef REF_CHECK
 223     if (i < 2) {
 224         fprintf(stderr, "DH_up, bad reference count\n");
 225         abort();
 226     }
 227 #endif
 228     return ((i > 1) ? 1 : 0);
 229 }
 230
 231 int DH_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,
 232                         CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func)
 233 {
 234     return CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_DH, argl, argp,
 235                                    new_func, dup_func, free_func);
 236 }
 237
 238 int DH_set_ex_data(DH *d, int idx, void *arg)
 239 {
 240     return (CRYPTO_set_ex_data(&d->ex_data, idx, arg));
 241 }
 242
 243 void *DH_get_ex_data(DH *d, int idx)
 244 {
 245     return (CRYPTO_get_ex_data(&d->ex_data, idx));
 246 }
 247
 248 int DH_size(const DH *dh)
 249 {
 250     return (BN_num_bytes(dh->p));
 251 }