crypto/external/bsd/openssl/dist/engines/e_gmp.c

   1 /* crypto/engine/e_gmp.c */
   2 /*
   3  * Written by Geoff Thorpe (geoff@geoffthorpe.net) for the OpenSSL project
   4  * 2003.
   5  */
   6 /* ====================================================================
   7  * Copyright (c) 1999-2001 The OpenSSL Project.  All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  *
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  *
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in
  18  *    the documentation and/or other materials provided with the
  19  *    distribution.
  20  *
  21  * 3. All advertising materials mentioning features or use of this
  22  *    software must display the following acknowledgment:
  23  *    "This product includes software developed by the OpenSSL Project
  24  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
  25  *
  26  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  27  *    endorse or promote products derived from this software without
  28  *    prior written permission. For written permission, please contact
  29  *    licensing@OpenSSL.org.
  30  *
  31  * 5. Products derived from this software may not be called "OpenSSL"
  32  *    nor may "OpenSSL" appear in their names without prior written
  33  *    permission of the OpenSSL Project.
  34  *
  35  * 6. Redistributions of any form whatsoever must retain the following
  36  *    acknowledgment:
  37  *    "This product includes software developed by the OpenSSL Project
  38  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
  39  *
  40  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  41  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  42  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  43  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
  44  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  45  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  46  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  47  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  49  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  50  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  51  * OF THE POSSIBILITY OF SUCH DAMAGE.
  52  * ====================================================================
  53  *
  54  * This product includes cryptographic software written by Eric Young
  55  * (eay@cryptsoft.com).  This product includes software written by Tim
  56  * Hudson (tjh@cryptsoft.com).
  57  *
  58  */
  59
  60 /*
  61  * This engine is not (currently) compiled in by default. Do enable it,
  62  * reconfigure OpenSSL with "enable-gmp -lgmp". The GMP libraries and headers
  63  * must reside in one of the paths searched by the compiler/linker, otherwise
  64  * paths must be specified - eg. try configuring with "enable-gmp
  65  * -I<includepath> -L<libpath> -lgmp". YMMV.
  66  */
  67
  68 /*-
  69  * As for what this does - it's a largely unoptimised implementation of an
  70  * ENGINE that uses the GMP library to perform RSA private key operations. To
  71  * obtain more information about what "unoptimised" means, see my original mail
  72  * on the subject (though ignore the build instructions which have since
  73  * changed);
  74  *
  75  *    http://www.mail-archive.com/openssl-dev@openssl.org/msg12227.html
  76  *
  77  * On my athlon system at least, it appears the builtin OpenSSL code is now
  78  * slightly faster, which is to say that the RSA-related MPI performance
  79  * between OpenSSL's BIGNUM and GMP's mpz implementations is probably pretty
  80  * balanced for this chip, and so the performance degradation in this ENGINE by
  81  * having to convert to/from GMP formats (and not being able to cache
  82  * montgomery forms) is probably the difference. However, if some unconfirmed
  83  * reports from users is anything to go by, the situation on some other
  84  * chipsets might be a good deal more favourable to the GMP version (eg. PPC).
  85  * Feedback welcome. */
  86
  87 #include <stdio.h>
  88 #include <string.h>
  89 #include <openssl/crypto.h>
  90 #include <openssl/buffer.h>
  91 #include <openssl/engine.h>
  92 #ifndef OPENSSL_NO_RSA
  93 # include <openssl/rsa.h>
  94 #endif
  95 #include <openssl/bn.h>
  96
  97 #ifndef OPENSSL_NO_HW
  98 # ifndef OPENSSL_NO_GMP
  99
 100 #  include <gmp.h>
 101
 102 #  define E_GMP_LIB_NAME "gmp engine"
 103 #  include "e_gmp_err.c"
 104
 105 static int e_gmp_destroy(ENGINE *e);
 106 static int e_gmp_init(ENGINE *e);
 107 static int e_gmp_finish(ENGINE *e);
 108 static int e_gmp_ctrl(ENGINE *e, int cmd, long i, void *p, void (*f) (void));
 109
 110 #  ifndef OPENSSL_NO_RSA
 111 /* RSA stuff */
 112 static int e_gmp_rsa_mod_exp(BIGNUM *r, const BIGNUM *I, RSA *rsa,
 113                              BN_CTX *ctx);
 114 static int e_gmp_rsa_finish(RSA *r);
 115 #  endif
 116
 117 /* The definitions for control commands specific to this engine */
 118 /* #define E_GMP_CMD_SO_PATH            ENGINE_CMD_BASE */
 119 static const ENGINE_CMD_DEFN e_gmp_cmd_defns[] = {
 120 #  if 0
 121     {E_GMP_CMD_SO_PATH,
 122      "SO_PATH",
 123      "Specifies the path to the 'e_gmp' shared library",
 124      ENGINE_CMD_FLAG_STRING},
 125 #  endif
 126     {0, NULL, NULL, 0}
 127 };
 128
 129 #  ifndef OPENSSL_NO_RSA
 130 /* Our internal RSA_METHOD that we provide pointers to */
 131 static RSA_METHOD e_gmp_rsa = {
 132     "GMP RSA method",
 133     NULL,
 134     NULL,
 135     NULL,
 136     NULL,
 137     e_gmp_rsa_mod_exp,
 138     NULL,
 139     NULL,
 140     e_gmp_rsa_finish,
 141     /*
 142      * These flags initialise montgomery crud that GMP ignores, however it
 143      * makes sure the public key ops (which are done in openssl) don't seem
 144      * *slower* than usual :-)
 145      */
 146     RSA_FLAG_CACHE_PUBLIC | RSA_FLAG_CACHE_PRIVATE,
 147     NULL,
 148     NULL,
 149     NULL
 150 };
 151 #  endif
 152
 153 /* Constants used when creating the ENGINE */
 154 static const char *engine_e_gmp_id = "gmp";
 155 static const char *engine_e_gmp_name = "GMP engine support";
 156
 157 /*
 158  * This internal function is used by ENGINE_gmp() and possibly by the
 159  * "dynamic" ENGINE support too
 160  */
 161 static int bind_helper(ENGINE *e)
 162 {
 163 #  ifndef OPENSSL_NO_RSA
 164     const RSA_METHOD *meth1;
 165 #  endif
 166     if (!ENGINE_set_id(e, engine_e_gmp_id) ||
 167         !ENGINE_set_name(e, engine_e_gmp_name) ||
 168 #  ifndef OPENSSL_NO_RSA
 169         !ENGINE_set_RSA(e, &e_gmp_rsa) ||
 170 #  endif
 171         !ENGINE_set_destroy_function(e, e_gmp_destroy) ||
 172         !ENGINE_set_init_function(e, e_gmp_init) ||
 173         !ENGINE_set_finish_function(e, e_gmp_finish) ||
 174         !ENGINE_set_ctrl_function(e, e_gmp_ctrl) ||
 175         !ENGINE_set_cmd_defns(e, e_gmp_cmd_defns))
 176         return 0;
 177
 178 #  ifndef OPENSSL_NO_RSA
 179     meth1 = RSA_PKCS1_SSLeay();
 180     e_gmp_rsa.rsa_pub_enc = meth1->rsa_pub_enc;
 181     e_gmp_rsa.rsa_pub_dec = meth1->rsa_pub_dec;
 182     e_gmp_rsa.rsa_priv_enc = meth1->rsa_priv_enc;
 183     e_gmp_rsa.rsa_priv_dec = meth1->rsa_priv_dec;
 184     e_gmp_rsa.bn_mod_exp = meth1->bn_mod_exp;
 185 #  endif
 186
 187     /* Ensure the e_gmp error handling is set up */
 188     ERR_load_GMP_strings();
 189     return 1;
 190 }
 191
 192 static ENGINE *engine_gmp(void)
 193 {
 194     ENGINE *ret = ENGINE_new();
 195     if (!ret)
 196         return NULL;
 197     if (!bind_helper(ret)) {
 198         ENGINE_free(ret);
 199         return NULL;
 200     }
 201     return ret;
 202 }
 203
 204 void ENGINE_load_gmp(void)
 205 {
 206     /* Copied from eng_[openssl|dyn].c */
 207     ENGINE *toadd = engine_gmp();
 208     if (!toadd)
 209         return;
 210     ENGINE_add(toadd);
 211     ENGINE_free(toadd);
 212     ERR_clear_error();
 213 }
 214
 215 #  ifndef OPENSSL_NO_RSA
 216 /* Used to attach our own key-data to an RSA structure */
 217 static int hndidx_rsa = -1;
 218 #  endif
 219
 220 static int e_gmp_destroy(ENGINE *e)
 221 {
 222     ERR_unload_GMP_strings();
 223     return 1;
 224 }
 225
 226 /* (de)initialisation functions. */
 227 static int e_gmp_init(ENGINE *e)
 228 {
 229 #  ifndef OPENSSL_NO_RSA
 230     if (hndidx_rsa == -1)
 231         hndidx_rsa = RSA_get_ex_new_index(0,
 232                                           "GMP-based RSA key handle",
 233                                           NULL, NULL, NULL);
 234 #  endif
 235     if (hndidx_rsa == -1)
 236         return 0;
 237     return 1;
 238 }
 239
 240 static int e_gmp_finish(ENGINE *e)
 241 {
 242     return 1;
 243 }
 244
 245 static int e_gmp_ctrl(ENGINE *e, int cmd, long i, void *p, void (*f) (void))
 246 {
 247     int to_return = 1;
 248
 249     switch (cmd) {
 250 #  if 0
 251     case E_GMP_CMD_SO_PATH:
 252         /* ... */
 253 #  endif
 254         /* The command isn't understood by this engine */
 255     default:
 256         GMPerr(GMP_F_E_GMP_CTRL, GMP_R_CTRL_COMMAND_NOT_IMPLEMENTED);
 257         to_return = 0;
 258         break;
 259     }
 260
 261     return to_return;
 262 }
 263
 264 /*
 265  * Most often limb sizes will be the same. If not, we use hex conversion
 266  * which is neat, but extremely inefficient.
 267  */
 268 static int bn2gmp(const BIGNUM *bn, mpz_t g)
 269 {
 270     bn_check_top(bn);
 271     if (((sizeof(bn->d[0]) * 8) == GMP_NUMB_BITS) &&
 272         (BN_BITS2 == GMP_NUMB_BITS)) {
 273         /* The common case */
 274         if (!_mpz_realloc(g, bn->top))
 275             return 0;
 276         memcpy(&g->_mp_d[0], &bn->d[0], bn->top * sizeof(bn->d[0]));
 277         g->_mp_size = bn->top;
 278         if (bn->neg)
 279             g->_mp_size = -g->_mp_size;
 280         return 1;
 281     } else {
 282         int toret;
 283         char *tmpchar = BN_bn2hex(bn);
 284         if (!tmpchar)
 285             return 0;
 286         toret = (mpz_set_str(g, tmpchar, 16) == 0 ? 1 : 0);
 287         OPENSSL_free(tmpchar);
 288         return toret;
 289     }
 290 }
 291
 292 static int gmp2bn(mpz_t g, BIGNUM *bn)
 293 {
 294     if (((sizeof(bn->d[0]) * 8) == GMP_NUMB_BITS) &&
 295         (BN_BITS2 == GMP_NUMB_BITS)) {
 296         /* The common case */
 297         int s = (g->_mp_size >= 0) ? g->_mp_size : -g->_mp_size;
 298         BN_zero(bn);
 299         if (bn_expand2(bn, s) == NULL)
 300             return 0;
 301         bn->top = s;
 302         memcpy(&bn->d[0], &g->_mp_d[0], s * sizeof(bn->d[0]));
 303         bn_correct_top(bn);
 304         bn->neg = g->_mp_size >= 0 ? 0 : 1;
 305         return 1;
 306     } else {
 307         int toret;
 308         char *tmpchar = OPENSSL_malloc(mpz_sizeinbase(g, 16) + 10);
 309         if (!tmpchar)
 310             return 0;
 311         mpz_get_str(tmpchar, 16, g);
 312         toret = BN_hex2bn(&bn, tmpchar);
 313         OPENSSL_free(tmpchar);
 314         return toret;
 315     }
 316 }
 317
 318 #  ifndef OPENSSL_NO_RSA
 319 typedef struct st_e_gmp_rsa_ctx {
 320     int public_only;
 321     mpz_t n;
 322     mpz_t d;
 323     mpz_t e;
 324     mpz_t p;
 325     mpz_t q;
 326     mpz_t dmp1;
 327     mpz_t dmq1;
 328     mpz_t iqmp;
 329     mpz_t r0, r1, I0, m1;
 330 } E_GMP_RSA_CTX;
 331
 332 static E_GMP_RSA_CTX *e_gmp_get_rsa(RSA *rsa)
 333 {
 334     E_GMP_RSA_CTX *hptr = RSA_get_ex_data(rsa, hndidx_rsa);
 335     if (hptr)
 336         return hptr;
 337     hptr = OPENSSL_malloc(sizeof(E_GMP_RSA_CTX));
 338     if (!hptr)
 339         return NULL;
 340     /*
 341      * These inits could probably be replaced by more intelligent mpz_init2()
 342      * versions, to reduce malloc-thrashing.
 343      */
 344     mpz_init(hptr->n);
 345     mpz_init(hptr->d);
 346     mpz_init(hptr->e);
 347     mpz_init(hptr->p);
 348     mpz_init(hptr->q);
 349     mpz_init(hptr->dmp1);
 350     mpz_init(hptr->dmq1);
 351     mpz_init(hptr->iqmp);
 352     mpz_init(hptr->r0);
 353     mpz_init(hptr->r1);
 354     mpz_init(hptr->I0);
 355     mpz_init(hptr->m1);
 356     if (!bn2gmp(rsa->n, hptr->n) || !bn2gmp(rsa->e, hptr->e))
 357         goto err;
 358     if (!rsa->p || !rsa->q || !rsa->d || !rsa->dmp1 || !rsa->dmq1
 359         || !rsa->iqmp) {
 360         hptr->public_only = 1;
 361         return hptr;
 362     }
 363     if (!bn2gmp(rsa->d, hptr->d) || !bn2gmp(rsa->p, hptr->p) ||
 364         !bn2gmp(rsa->q, hptr->q) || !bn2gmp(rsa->dmp1, hptr->dmp1) ||
 365         !bn2gmp(rsa->dmq1, hptr->dmq1) || !bn2gmp(rsa->iqmp, hptr->iqmp))
 366         goto err;
 367     hptr->public_only = 0;
 368     RSA_set_ex_data(rsa, hndidx_rsa, hptr);
 369     return hptr;
 370  err:
 371     mpz_clear(hptr->n);
 372     mpz_clear(hptr->d);
 373     mpz_clear(hptr->e);
 374     mpz_clear(hptr->p);
 375     mpz_clear(hptr->q);
 376     mpz_clear(hptr->dmp1);
 377     mpz_clear(hptr->dmq1);
 378     mpz_clear(hptr->iqmp);
 379     mpz_clear(hptr->r0);
 380     mpz_clear(hptr->r1);
 381     mpz_clear(hptr->I0);
 382     mpz_clear(hptr->m1);
 383     OPENSSL_free(hptr);
 384     return NULL;
 385 }
 386
 387 static int e_gmp_rsa_finish(RSA *rsa)
 388 {
 389     E_GMP_RSA_CTX *hptr = RSA_get_ex_data(rsa, hndidx_rsa);
 390     if (!hptr)
 391         return 0;
 392     mpz_clear(hptr->n);
 393     mpz_clear(hptr->d);
 394     mpz_clear(hptr->e);
 395     mpz_clear(hptr->p);
 396     mpz_clear(hptr->q);
 397     mpz_clear(hptr->dmp1);
 398     mpz_clear(hptr->dmq1);
 399     mpz_clear(hptr->iqmp);
 400     mpz_clear(hptr->r0);
 401     mpz_clear(hptr->r1);
 402     mpz_clear(hptr->I0);
 403     mpz_clear(hptr->m1);
 404     OPENSSL_free(hptr);
 405     RSA_set_ex_data(rsa, hndidx_rsa, NULL);
 406     return 1;
 407 }
 408
 409 static int e_gmp_rsa_mod_exp(BIGNUM *r, const BIGNUM *I, RSA *rsa,
 410                              BN_CTX *ctx)
 411 {
 412     E_GMP_RSA_CTX *hptr;
 413     int to_return = 0;
 414
 415     hptr = e_gmp_get_rsa(rsa);
 416     if (!hptr) {
 417         GMPerr(GMP_F_E_GMP_RSA_MOD_EXP, GMP_R_KEY_CONTEXT_ERROR);
 418         return 0;
 419     }
 420     if (hptr->public_only) {
 421         GMPerr(GMP_F_E_GMP_RSA_MOD_EXP, GMP_R_MISSING_KEY_COMPONENTS);
 422         return 0;
 423     }
 424
 425     /* ugh!!! */
 426     if (!bn2gmp(I, hptr->I0))
 427         return 0;
 428
 429     /*
 430      * This is basically the CRT logic in crypto/rsa/rsa_eay.c reworded into
 431      * GMP-speak. It may be that GMP's API facilitates cleaner formulations
 432      * of this stuff, eg. better handling of negatives, or functions that
 433      * combine operations.
 434      */
 435
 436     mpz_mod(hptr->r1, hptr->I0, hptr->q);
 437     mpz_powm(hptr->m1, hptr->r1, hptr->dmq1, hptr->q);
 438
 439     mpz_mod(hptr->r1, hptr->I0, hptr->p);
 440     mpz_powm(hptr->r0, hptr->r1, hptr->dmp1, hptr->p);
 441
 442     mpz_sub(hptr->r0, hptr->r0, hptr->m1);
 443
 444     if (mpz_sgn(hptr->r0) < 0)
 445         mpz_add(hptr->r0, hptr->r0, hptr->p);
 446     mpz_mul(hptr->r1, hptr->r0, hptr->iqmp);
 447     mpz_mod(hptr->r0, hptr->r1, hptr->p);
 448
 449     if (mpz_sgn(hptr->r0) < 0)
 450         mpz_add(hptr->r0, hptr->r0, hptr->p);
 451     mpz_mul(hptr->r1, hptr->r0, hptr->q);
 452     mpz_add(hptr->r0, hptr->r1, hptr->m1);
 453
 454     /* ugh!!! */
 455     if (gmp2bn(hptr->r0, r))
 456         to_return = 1;
 457
 458     return 1;
 459 }
 460 #  endif
 461
 462 # endif                         /* !OPENSSL_NO_GMP */
 463
 464 /*
 465  * This stuff is needed if this ENGINE is being compiled into a
 466  * self-contained shared-library.
 467  */
 468 # ifndef OPENSSL_NO_DYNAMIC_ENGINE
 469 IMPLEMENT_DYNAMIC_CHECK_FN()
 470 #  ifndef OPENSSL_NO_GMP
 471 static int bind_fn(ENGINE *e, const char *id)
 472 {
 473     if (id && (strcmp(id, engine_e_gmp_id) != 0))
 474         return 0;
 475     if (!bind_helper(e))
 476         return 0;
 477     return 1;
 478 }
 479
 480 IMPLEMENT_DYNAMIC_BIND_FN(bind_fn)
 481 #  else
 482 OPENSSL_EXPORT
 483     int bind_engine(ENGINE *e, const char *id, const dynamic_fns *fns);
 484 OPENSSL_EXPORT
 485     int bind_engine(ENGINE *e, const char *id, const dynamic_fns *fns)
 486 {
 487     return 0;
 488 }
 489 #  endif
 490 # endif                         /* !OPENSSL_NO_DYNAMIC_ENGINE */
 491
 492 #endif                          /* !OPENSSL_NO_HW */