crypto/openssl-0.9.7d/crypto/dsa/dsa_lib.c

   1 /* crypto/dsa/dsa_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 /* Original version from Steven Schoch <schoch@sheba.arc.nasa.gov> */
  60
  61 #include <stdio.h>
  62 #include "cryptlib.h"
  63 #include <openssl/bn.h>
  64 #include <openssl/dsa.h>
  65 #include <openssl/asn1.h>
  66 #ifndef OPENSSL_NO_ENGINE
  67 #include <openssl/engine.h>
  68 #endif
  69
  70 const char *DSA_version="DSA" OPENSSL_VERSION_PTEXT;
  71
  72 static const DSA_METHOD *default_DSA_method = NULL;
  73
  74 void DSA_set_default_method(const DSA_METHOD *meth)
  75         {
  76         default_DSA_method = meth;
  77         }
  78
  79 const DSA_METHOD *DSA_get_default_method(void)
  80         {
  81         if(!default_DSA_method)
  82                 default_DSA_method = DSA_OpenSSL();
  83         return default_DSA_method;
  84         }
  85
  86 DSA *DSA_new(void)
  87         {
  88         return DSA_new_method(NULL);
  89         }
  90
  91 int DSA_set_method(DSA *dsa, const DSA_METHOD *meth)
  92         {
  93         /* NB: The caller is specifically setting a method, so it's not up to us
  94          * to deal with which ENGINE it comes from. */
  95         const DSA_METHOD *mtmp;
  96         mtmp = dsa->meth;
  97         if (mtmp->finish) mtmp->finish(dsa);
  98 #ifndef OPENSSL_NO_ENGINE
  99         if (dsa->engine)
 100                 {
 101                 ENGINE_finish(dsa->engine);
 102                 dsa->engine = NULL;
 103                 }
 104 #endif
 105         dsa->meth = meth;
 106         if (meth->init) meth->init(dsa);
 107         return 1;
 108         }
 109
 110 DSA *DSA_new_method(ENGINE *engine)
 111         {
 112         DSA *ret;
 113
 114         ret=(DSA *)OPENSSL_malloc(sizeof(DSA));
 115         if (ret == NULL)
 116                 {
 117                 DSAerr(DSA_F_DSA_NEW_METHOD,ERR_R_MALLOC_FAILURE);
 118                 return(NULL);
 119                 }
 120         ret->meth = DSA_get_default_method();
 121 #ifndef OPENSSL_NO_ENGINE
 122         if (engine)
 123                 {
 124                 if (!ENGINE_init(engine))
 125                         {
 126                         DSAerr(DSA_F_DSA_NEW_METHOD, ERR_R_ENGINE_LIB);
 127                         OPENSSL_free(ret);
 128                         return NULL;
 129                         }
 130                 ret->engine = engine;
 131                 }
 132         else
 133                 ret->engine = ENGINE_get_default_DSA();
 134         if(ret->engine)
 135                 {
 136                 ret->meth = ENGINE_get_DSA(ret->engine);
 137                 if(!ret->meth)
 138                         {
 139                         DSAerr(DSA_F_DSA_NEW_METHOD,
 140                                 ERR_R_ENGINE_LIB);
 141                         ENGINE_finish(ret->engine);
 142                         OPENSSL_free(ret);
 143                         return NULL;
 144                         }
 145                 }
 146 #endif
 147
 148         ret->pad=0;
 149         ret->version=0;
 150         ret->write_params=1;
 151         ret->p=NULL;
 152         ret->q=NULL;
 153         ret->g=NULL;
 154
 155         ret->pub_key=NULL;
 156         ret->priv_key=NULL;
 157
 158         ret->kinv=NULL;
 159         ret->r=NULL;
 160         ret->method_mont_p=NULL;
 161
 162         ret->references=1;
 163         ret->flags=ret->meth->flags;
 164         CRYPTO_new_ex_data(CRYPTO_EX_INDEX_DSA, ret, &ret->ex_data);
 165         if ((ret->meth->init != NULL) && !ret->meth->init(ret))
 166                 {
 167 #ifndef OPENSSL_NO_ENGINE
 168                 if (ret->engine)
 169                         ENGINE_finish(ret->engine);
 170 #endif
 171                 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DSA, ret, &ret->ex_data);
 172                 OPENSSL_free(ret);
 173                 ret=NULL;
 174                 }
 175
 176         return(ret);
 177         }
 178
 179 void DSA_free(DSA *r)
 180         {
 181         int i;
 182
 183         if (r == NULL) return;
 184
 185         i=CRYPTO_add(&r->references,-1,CRYPTO_LOCK_DSA);
 186 #ifdef REF_PRINT
 187         REF_PRINT("DSA",r);
 188 #endif
 189         if (i > 0) return;
 190 #ifdef REF_CHECK
 191         if (i < 0)
 192                 {
 193                 fprintf(stderr,"DSA_free, bad reference count\n");
 194                 abort();
 195                 }
 196 #endif
 197
 198         if(r->meth->finish)
 199                 r->meth->finish(r);
 200 #ifndef OPENSSL_NO_ENGINE
 201         if(r->engine)
 202                 ENGINE_finish(r->engine);
 203 #endif
 204
 205         CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DSA, r, &r->ex_data);
 206
 207         if (r->p != NULL) BN_clear_free(r->p);
 208         if (r->q != NULL) BN_clear_free(r->q);
 209         if (r->g != NULL) BN_clear_free(r->g);
 210         if (r->pub_key != NULL) BN_clear_free(r->pub_key);
 211         if (r->priv_key != NULL) BN_clear_free(r->priv_key);
 212         if (r->kinv != NULL) BN_clear_free(r->kinv);
 213         if (r->r != NULL) BN_clear_free(r->r);
 214         OPENSSL_free(r);
 215         }
 216
 217 int DSA_up_ref(DSA *r)
 218         {
 219         int i = CRYPTO_add(&r->references, 1, CRYPTO_LOCK_DSA);
 220 #ifdef REF_PRINT
 221         REF_PRINT("DSA",r);
 222 #endif
 223 #ifdef REF_CHECK
 224         if (i < 2)
 225                 {
 226                 fprintf(stderr, "DSA_up_ref, bad reference count\n");
 227                 abort();
 228                 }
 229 #endif
 230         return ((i > 1) ? 1 : 0);
 231         }
 232
 233 int DSA_size(const DSA *r)
 234         {
 235         int ret,i;
 236         ASN1_INTEGER bs;
 237         unsigned char buf[4];   /* 4 bytes looks really small.
 238                                    However, i2d_ASN1_INTEGER() will not look
 239                                    beyond the first byte, as long as the second
 240                                    parameter is NULL. */
 241
 242         i=BN_num_bits(r->q);
 243         bs.length=(i+7)/8;
 244         bs.data=buf;
 245         bs.type=V_ASN1_INTEGER;
 246         /* If the top bit is set the asn1 encoding is 1 larger. */
 247         buf[0]=0xff;
 248
 249         i=i2d_ASN1_INTEGER(&bs,NULL);
 250         i+=i; /* r and s */
 251         ret=ASN1_object_size(1,i,V_ASN1_SEQUENCE);
 252         return(ret);
 253         }
 254
 255 int DSA_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,
 256              CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func)
 257         {
 258         return CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_DSA, argl, argp,
 259                                 new_func, dup_func, free_func);
 260         }
 261
 262 int DSA_set_ex_data(DSA *d, int idx, void *arg)
 263         {
 264         return(CRYPTO_set_ex_data(&d->ex_data,idx,arg));
 265         }
 266
 267 void *DSA_get_ex_data(DSA *d, int idx)
 268         {
 269         return(CRYPTO_get_ex_data(&d->ex_data,idx));
 270         }
 271
 272 #ifndef OPENSSL_NO_DH
 273 DH *DSA_dup_DH(const DSA *r)
 274         {
 275         /* DSA has p, q, g, optional pub_key, optional priv_key.
 276          * DH has p, optional length, g, optional pub_key, optional priv_key.
 277          */
 278
 279         DH *ret = NULL;
 280
 281         if (r == NULL)
 282                 goto err;
 283         ret = DH_new();
 284         if (ret == NULL)
 285                 goto err;
 286         if (r->p != NULL)
 287                 if ((ret->p = BN_dup(r->p)) == NULL)
 288                         goto err;
 289         if (r->q != NULL)
 290                 ret->length = BN_num_bits(r->q);
 291         if (r->g != NULL)
 292                 if ((ret->g = BN_dup(r->g)) == NULL)
 293                         goto err;
 294         if (r->pub_key != NULL)
 295                 if ((ret->pub_key = BN_dup(r->pub_key)) == NULL)
 296                         goto err;
 297         if (r->priv_key != NULL)
 298                 if ((ret->priv_key = BN_dup(r->priv_key)) == NULL)
 299                         goto err;
 300
 301         return ret;
 302
 303  err:
 304         if (ret != NULL)
 305                 DH_free(ret);
 306         return NULL;
 307         }
 308 #endif