crypto/openssl-0.9/engines/e_gmp.c

   1 /* crypto/engine/e_gmp.c */
   2 /* Written by Geoff Thorpe (geoff@geoffthorpe.net) for the OpenSSL
   3  * project 2003.
   4  */
   5 /* ====================================================================
   6  * Copyright (c) 1999-2001 The OpenSSL Project.  All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  *
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  *
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in
  17  *    the documentation and/or other materials provided with the
  18  *    distribution.
  19  *
  20  * 3. All advertising materials mentioning features or use of this
  21  *    software must display the following acknowledgment:
  22  *    "This product includes software developed by the OpenSSL Project
  23  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
  24  *
  25  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  26  *    endorse or promote products derived from this software without
  27  *    prior written permission. For written permission, please contact
  28  *    licensing@OpenSSL.org.
  29  *
  30  * 5. Products derived from this software may not be called "OpenSSL"
  31  *    nor may "OpenSSL" appear in their names without prior written
  32  *    permission of the OpenSSL Project.
  33  *
  34  * 6. Redistributions of any form whatsoever must retain the following
  35  *    acknowledgment:
  36  *    "This product includes software developed by the OpenSSL Project
  37  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
  38  *
  39  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  40  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  41  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  42  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
  43  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  44  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  45  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  46  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  47  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  48  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  49  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  50  * OF THE POSSIBILITY OF SUCH DAMAGE.
  51  * ====================================================================
  52  *
  53  * This product includes cryptographic software written by Eric Young
  54  * (eay@cryptsoft.com).  This product includes software written by Tim
  55  * Hudson (tjh@cryptsoft.com).
  56  *
  57  */
  58
  59 /* This engine is not (currently) compiled in by default. Do enable it,
  60  * reconfigure OpenSSL with "enable-gmp -lgmp". The GMP libraries and
  61  * headers must reside in one of the paths searched by the compiler/linker,
  62  * otherwise paths must be specified - eg. try configuring with
  63  * "enable-gmp -I<includepath> -L<libpath> -lgmp". YMMV. */
  64
  65 /* As for what this does - it's a largely unoptimised implementation of an
  66  * ENGINE that uses the GMP library to perform RSA private key operations. To
  67  * obtain more information about what "unoptimised" means, see my original mail
  68  * on the subject (though ignore the build instructions which have since
  69  * changed);
  70  *
  71  *    http://www.mail-archive.com/openssl-dev@openssl.org/msg12227.html
  72  *
  73  * On my athlon system at least, it appears the builtin OpenSSL code is now
  74  * slightly faster, which is to say that the RSA-related MPI performance
  75  * between OpenSSL's BIGNUM and GMP's mpz implementations is probably pretty
  76  * balanced for this chip, and so the performance degradation in this ENGINE by
  77  * having to convert to/from GMP formats (and not being able to cache
  78  * montgomery forms) is probably the difference. However, if some unconfirmed
  79  * reports from users is anything to go by, the situation on some other
  80  * chipsets might be a good deal more favourable to the GMP version (eg. PPC).
  81  * Feedback welcome. */
  82
  83 #include <stdio.h>
  84 #include <string.h>
  85 #include <openssl/crypto.h>
  86 #include <openssl/buffer.h>
  87 #include <openssl/engine.h>
  88 #include <openssl/rsa.h>
  89 #include <openssl/bn.h>
  90
  91 #ifndef OPENSSL_NO_HW
  92 #ifndef OPENSSL_NO_GMP
  93
  94 #include <gmp.h>
  95
  96 #define E_GMP_LIB_NAME "gmp engine"
  97 #include "e_gmp_err.c"
  98
  99 static int e_gmp_destroy(ENGINE *e);
 100 static int e_gmp_init(ENGINE *e);
 101 static int e_gmp_finish(ENGINE *e);
 102 static int e_gmp_ctrl(ENGINE *e, int cmd, long i, void *p, void (*f)(void));
 103
 104 #ifndef OPENSSL_NO_RSA
 105 /* RSA stuff */
 106 static int e_gmp_rsa_mod_exp(BIGNUM *r, const BIGNUM *I, RSA *rsa, BN_CTX *ctx);
 107 static int e_gmp_rsa_finish(RSA *r);
 108 #endif
 109
 110 /* The definitions for control commands specific to this engine */
 111 /* #define E_GMP_CMD_SO_PATH            ENGINE_CMD_BASE */
 112 static const ENGINE_CMD_DEFN e_gmp_cmd_defns[] = {
 113 #if 0
 114         {E_GMP_CMD_SO_PATH,
 115                 "SO_PATH",
 116                 "Specifies the path to the 'e_gmp' shared library",
 117                 ENGINE_CMD_FLAG_STRING},
 118 #endif
 119         {0, NULL, NULL, 0}
 120         };
 121
 122 #ifndef OPENSSL_NO_RSA
 123 /* Our internal RSA_METHOD that we provide pointers to */
 124 static RSA_METHOD e_gmp_rsa =
 125         {
 126         "GMP RSA method",
 127         NULL,
 128         NULL,
 129         NULL,
 130         NULL,
 131         e_gmp_rsa_mod_exp,
 132         NULL,
 133         NULL,
 134         e_gmp_rsa_finish,
 135         /* These flags initialise montgomery crud that GMP ignores, however it
 136          * makes sure the public key ops (which are done in openssl) don't seem
 137          * *slower* than usual :-) */
 138         RSA_FLAG_CACHE_PUBLIC|RSA_FLAG_CACHE_PRIVATE,
 139         NULL,
 140         NULL,
 141         NULL
 142         };
 143 #endif
 144
 145 /* Constants used when creating the ENGINE */
 146 static const char *engine_e_gmp_id = "gmp";
 147 static const char *engine_e_gmp_name = "GMP engine support";
 148
 149 /* This internal function is used by ENGINE_gmp() and possibly by the
 150  * "dynamic" ENGINE support too */
 151 static int bind_helper(ENGINE *e)
 152         {
 153 #ifndef OPENSSL_NO_RSA
 154         const RSA_METHOD *meth1;
 155 #endif
 156         if(!ENGINE_set_id(e, engine_e_gmp_id) ||
 157                         !ENGINE_set_name(e, engine_e_gmp_name) ||
 158 #ifndef OPENSSL_NO_RSA
 159                         !ENGINE_set_RSA(e, &e_gmp_rsa) ||
 160 #endif
 161                         !ENGINE_set_destroy_function(e, e_gmp_destroy) ||
 162                         !ENGINE_set_init_function(e, e_gmp_init) ||
 163                         !ENGINE_set_finish_function(e, e_gmp_finish) ||
 164                         !ENGINE_set_ctrl_function(e, e_gmp_ctrl) ||
 165                         !ENGINE_set_cmd_defns(e, e_gmp_cmd_defns))
 166                 return 0;
 167
 168 #ifndef OPENSSL_NO_RSA
 169         meth1 = RSA_PKCS1_SSLeay();
 170         e_gmp_rsa.rsa_pub_enc = meth1->rsa_pub_enc;
 171         e_gmp_rsa.rsa_pub_dec = meth1->rsa_pub_dec;
 172         e_gmp_rsa.rsa_priv_enc = meth1->rsa_priv_enc;
 173         e_gmp_rsa.rsa_priv_dec = meth1->rsa_priv_dec;
 174         e_gmp_rsa.bn_mod_exp = meth1->bn_mod_exp;
 175 #endif
 176
 177         /* Ensure the e_gmp error handling is set up */
 178         ERR_load_GMP_strings();
 179         return 1;
 180         }
 181
 182 static ENGINE *engine_gmp(void)
 183         {
 184         ENGINE *ret = ENGINE_new();
 185         if(!ret)
 186                 return NULL;
 187         if(!bind_helper(ret))
 188                 {
 189                 ENGINE_free(ret);
 190                 return NULL;
 191                 }
 192         return ret;
 193         }
 194
 195 void ENGINE_load_gmp(void)
 196         {
 197         /* Copied from eng_[openssl|dyn].c */
 198         ENGINE *toadd = engine_gmp();
 199         if(!toadd) return;
 200         ENGINE_add(toadd);
 201         ENGINE_free(toadd);
 202         ERR_clear_error();
 203         }
 204
 205 #ifndef OPENSSL_NO_RSA
 206 /* Used to attach our own key-data to an RSA structure */
 207 static int hndidx_rsa = -1;
 208 #endif
 209
 210 static int e_gmp_destroy(ENGINE *e)
 211         {
 212         ERR_unload_GMP_strings();
 213         return 1;
 214         }
 215
 216 /* (de)initialisation functions. */
 217 static int e_gmp_init(ENGINE *e)
 218         {
 219 #ifndef OPENSSL_NO_RSA
 220         if (hndidx_rsa == -1)
 221                 hndidx_rsa = RSA_get_ex_new_index(0,
 222                         "GMP-based RSA key handle",
 223                         NULL, NULL, NULL);
 224 #endif
 225         if (hndidx_rsa == -1)
 226                 return 0;
 227         return 1;
 228         }
 229
 230 static int e_gmp_finish(ENGINE *e)
 231         {
 232         return 1;
 233         }
 234
 235 static int e_gmp_ctrl(ENGINE *e, int cmd, long i, void *p, void (*f)(void))
 236         {
 237         int to_return = 1;
 238
 239         switch(cmd)
 240                 {
 241 #if 0
 242         case E_GMP_CMD_SO_PATH:
 243                 /* ... */
 244 #endif
 245         /* The command isn't understood by this engine */
 246         default:
 247                 GMPerr(GMP_F_E_GMP_CTRL,
 248                         GMP_R_CTRL_COMMAND_NOT_IMPLEMENTED);
 249                 to_return = 0;
 250                 break;
 251                 }
 252
 253         return to_return;
 254         }
 255
 256
 257 /* Most often limb sizes will be the same. If not, we use hex conversion
 258  * which is neat, but extremely inefficient. */
 259 static int bn2gmp(const BIGNUM *bn, mpz_t g)
 260         {
 261         bn_check_top(bn);
 262         if(((sizeof(bn->d[0]) * 8) == GMP_NUMB_BITS) &&
 263                         (BN_BITS2 == GMP_NUMB_BITS))
 264                 {
 265                 /* The common case */
 266                 if(!_mpz_realloc (g, bn->top))
 267                         return 0;
 268                 memcpy(&g->_mp_d[0], &bn->d[0], bn->top * sizeof(bn->d[0]));
 269                 g->_mp_size = bn->top;
 270                 if(bn->neg)
 271                         g->_mp_size = -g->_mp_size;
 272                 return 1;
 273                 }
 274         else
 275                 {
 276                 int toret;
 277                 char *tmpchar = BN_bn2hex(bn);
 278                 if(!tmpchar) return 0;
 279                 toret = (mpz_set_str(g, tmpchar, 16) == 0 ? 1 : 0);
 280                 OPENSSL_free(tmpchar);
 281                 return toret;
 282                 }
 283         }
 284
 285 static int gmp2bn(mpz_t g, BIGNUM *bn)
 286         {
 287         if(((sizeof(bn->d[0]) * 8) == GMP_NUMB_BITS) &&
 288                         (BN_BITS2 == GMP_NUMB_BITS))
 289                 {
 290                 /* The common case */
 291                 int s = (g->_mp_size >= 0) ? g->_mp_size : -g->_mp_size;
 292                 BN_zero(bn);
 293                 if(bn_expand2 (bn, s) == NULL)
 294                         return 0;
 295                 bn->top = s;
 296                 memcpy(&bn->d[0], &g->_mp_d[0], s * sizeof(bn->d[0]));
 297                 bn_correct_top(bn);
 298                 bn->neg = g->_mp_size >= 0 ? 0 : 1;
 299                 return 1;
 300                 }
 301         else
 302                 {
 303                 int toret;
 304                 char *tmpchar = OPENSSL_malloc(mpz_sizeinbase(g, 16) + 10);
 305                 if(!tmpchar) return 0;
 306                 mpz_get_str(tmpchar, 16, g);
 307                 toret = BN_hex2bn(&bn, tmpchar);
 308                 OPENSSL_free(tmpchar);
 309                 return toret;
 310                 }
 311         }
 312
 313 #ifndef OPENSSL_NO_RSA
 314 typedef struct st_e_gmp_rsa_ctx
 315         {
 316         int public_only;
 317         mpz_t n;
 318         mpz_t d;
 319         mpz_t e;
 320         mpz_t p;
 321         mpz_t q;
 322         mpz_t dmp1;
 323         mpz_t dmq1;
 324         mpz_t iqmp;
 325         mpz_t r0, r1, I0, m1;
 326         } E_GMP_RSA_CTX;
 327
 328 static E_GMP_RSA_CTX *e_gmp_get_rsa(RSA *rsa)
 329         {
 330         E_GMP_RSA_CTX *hptr = RSA_get_ex_data(rsa, hndidx_rsa);
 331         if(hptr) return hptr;
 332         hptr = OPENSSL_malloc(sizeof(E_GMP_RSA_CTX));
 333         if(!hptr) return NULL;
 334         /* These inits could probably be replaced by more intelligent
 335          * mpz_init2() versions, to reduce malloc-thrashing. */
 336         mpz_init(hptr->n);
 337         mpz_init(hptr->d);
 338         mpz_init(hptr->e);
 339         mpz_init(hptr->p);
 340         mpz_init(hptr->q);
 341         mpz_init(hptr->dmp1);
 342         mpz_init(hptr->dmq1);
 343         mpz_init(hptr->iqmp);
 344         mpz_init(hptr->r0);
 345         mpz_init(hptr->r1);
 346         mpz_init(hptr->I0);
 347         mpz_init(hptr->m1);
 348         if(!bn2gmp(rsa->n, hptr->n) || !bn2gmp(rsa->e, hptr->e))
 349                 goto err;
 350         if(!rsa->p || !rsa->q || !rsa->d || !rsa->dmp1 || !rsa->dmq1 || !rsa->iqmp)
 351                 {
 352                 hptr->public_only = 1;
 353                 return hptr;
 354                 }
 355         if(!bn2gmp(rsa->d, hptr->d) || !bn2gmp(rsa->p, hptr->p) ||
 356                         !bn2gmp(rsa->q, hptr->q) || !bn2gmp(rsa->dmp1, hptr->dmp1) ||
 357                         !bn2gmp(rsa->dmq1, hptr->dmq1) || !bn2gmp(rsa->iqmp, hptr->iqmp))
 358                 goto err;
 359         hptr->public_only = 0;
 360         RSA_set_ex_data(rsa, hndidx_rsa, hptr);
 361         return hptr;
 362 err:
 363         mpz_clear(hptr->n);
 364         mpz_clear(hptr->d);
 365         mpz_clear(hptr->e);
 366         mpz_clear(hptr->p);
 367         mpz_clear(hptr->q);
 368         mpz_clear(hptr->dmp1);
 369         mpz_clear(hptr->dmq1);
 370         mpz_clear(hptr->iqmp);
 371         mpz_clear(hptr->r0);
 372         mpz_clear(hptr->r1);
 373         mpz_clear(hptr->I0);
 374         mpz_clear(hptr->m1);
 375         OPENSSL_free(hptr);
 376         return NULL;
 377         }
 378
 379 static int e_gmp_rsa_finish(RSA *rsa)
 380         {
 381         E_GMP_RSA_CTX *hptr = RSA_get_ex_data(rsa, hndidx_rsa);
 382         if(!hptr) return 0;
 383         mpz_clear(hptr->n);
 384         mpz_clear(hptr->d);
 385         mpz_clear(hptr->e);
 386         mpz_clear(hptr->p);
 387         mpz_clear(hptr->q);
 388         mpz_clear(hptr->dmp1);
 389         mpz_clear(hptr->dmq1);
 390         mpz_clear(hptr->iqmp);
 391         mpz_clear(hptr->r0);
 392         mpz_clear(hptr->r1);
 393         mpz_clear(hptr->I0);
 394         mpz_clear(hptr->m1);
 395         OPENSSL_free(hptr);
 396         RSA_set_ex_data(rsa, hndidx_rsa, NULL);
 397         return 1;
 398         }
 399
 400 static int e_gmp_rsa_mod_exp(BIGNUM *r, const BIGNUM *I, RSA *rsa, BN_CTX *ctx)
 401         {
 402         E_GMP_RSA_CTX *hptr;
 403         int to_return = 0;
 404
 405         hptr = e_gmp_get_rsa(rsa);
 406         if(!hptr)
 407                 {
 408                 GMPerr(GMP_F_E_GMP_RSA_MOD_EXP,
 409                                 GMP_R_KEY_CONTEXT_ERROR);
 410                 return 0;
 411                 }
 412         if(hptr->public_only)
 413                 {
 414                 GMPerr(GMP_F_E_GMP_RSA_MOD_EXP,
 415                                 GMP_R_MISSING_KEY_COMPONENTS);
 416                 return 0;
 417                 }
 418
 419         /* ugh!!! */
 420         if(!bn2gmp(I, hptr->I0))
 421                 return 0;
 422
 423         /* This is basically the CRT logic in crypto/rsa/rsa_eay.c reworded into
 424          * GMP-speak. It may be that GMP's API facilitates cleaner formulations
 425          * of this stuff, eg. better handling of negatives, or functions that
 426          * combine operations. */
 427
 428         mpz_mod(hptr->r1, hptr->I0, hptr->q);
 429         mpz_powm(hptr->m1, hptr->r1, hptr->dmq1, hptr->q);
 430
 431         mpz_mod(hptr->r1, hptr->I0, hptr->p);
 432         mpz_powm(hptr->r0, hptr->r1, hptr->dmp1, hptr->p);
 433
 434         mpz_sub(hptr->r0, hptr->r0, hptr->m1);
 435
 436         if(mpz_sgn(hptr->r0) < 0)
 437                 mpz_add(hptr->r0, hptr->r0, hptr->p);
 438         mpz_mul(hptr->r1, hptr->r0, hptr->iqmp);
 439         mpz_mod(hptr->r0, hptr->r1, hptr->p);
 440
 441         if(mpz_sgn(hptr->r0) < 0)
 442                 mpz_add(hptr->r0, hptr->r0, hptr->p);
 443         mpz_mul(hptr->r1, hptr->r0, hptr->q);
 444         mpz_add(hptr->r0, hptr->r1, hptr->m1);
 445
 446         /* ugh!!! */
 447         if(gmp2bn(hptr->r0, r))
 448                 to_return = 1;
 449
 450         return 1;
 451         }
 452 #endif
 453
 454 /* This stuff is needed if this ENGINE is being compiled into a self-contained
 455  * shared-library. */
 456 #ifndef ENGINE_NO_DYNAMIC_SUPPORT
 457 static int bind_fn(ENGINE *e, const char *id)
 458         {
 459         if(id && (strcmp(id, engine_e_gmp_id) != 0))
 460                 return 0;
 461         if(!bind_helper(e))
 462                 return 0;
 463         return 1;
 464         }
 465 IMPLEMENT_DYNAMIC_CHECK_FN()
 466 IMPLEMENT_DYNAMIC_BIND_FN(bind_fn)
 467 #endif /* ENGINE_DYNAMIC_SUPPORT */
 468
 469 #endif /* !OPENSSL_NO_GMP */
 470 #endif /* !OPENSSL_NO_HW */
 471