crypto/openssl/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 "-DOPENSSL_USE_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  * "-DOPENSSL_USE_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
  89 #ifndef OPENSSL_NO_HW
  90 #if defined(OPENSSL_USE_GMP) && !defined(OPENSSL_NO_HW_GMP)
  91
  92 #include <gmp.h>
  93
  94 #define E_GMP_LIB_NAME "gmp engine"
  95 #include "e_gmp_err.c"
  96
  97 static int e_gmp_destroy(ENGINE *e);
  98 static int e_gmp_init(ENGINE *e);
  99 static int e_gmp_finish(ENGINE *e);
 100 static int e_gmp_ctrl(ENGINE *e, int cmd, long i, void *p, void (*f)(void));
 101
 102 #ifndef OPENSSL_NO_RSA
 103 /* RSA stuff */
 104 static int e_gmp_rsa_mod_exp(BIGNUM *r, const BIGNUM *I, RSA *rsa, BN_CTX *ctx);
 105 static int e_gmp_rsa_finish(RSA *r);
 106 #endif
 107
 108 /* The definitions for control commands specific to this engine */
 109 /* #define E_GMP_CMD_SO_PATH            ENGINE_CMD_BASE */
 110 static const ENGINE_CMD_DEFN e_gmp_cmd_defns[] = {
 111 #if 0
 112         {E_GMP_CMD_SO_PATH,
 113                 "SO_PATH",
 114                 "Specifies the path to the 'e_gmp' shared library",
 115                 ENGINE_CMD_FLAG_STRING},
 116 #endif
 117         {0, NULL, NULL, 0}
 118         };
 119
 120 #ifndef OPENSSL_NO_RSA
 121 /* Our internal RSA_METHOD that we provide pointers to */
 122 static RSA_METHOD e_gmp_rsa =
 123         {
 124         "GMP RSA method",
 125         NULL,
 126         NULL,
 127         NULL,
 128         NULL,
 129         e_gmp_rsa_mod_exp,
 130         NULL,
 131         NULL,
 132         e_gmp_rsa_finish,
 133         /* These flags initialise montgomery crud that GMP ignores, however it
 134          * makes sure the public key ops (which are done in openssl) don't seem
 135          * *slower* than usual :-) */
 136         RSA_FLAG_CACHE_PUBLIC|RSA_FLAG_CACHE_PRIVATE,
 137         NULL,
 138         NULL,
 139         NULL
 140         };
 141 #endif
 142
 143 /* Constants used when creating the ENGINE */
 144 static const char *engine_e_gmp_id = "gmp";
 145 static const char *engine_e_gmp_name = "GMP engine support";
 146
 147 /* This internal function is used by ENGINE_gmp() and possibly by the
 148  * "dynamic" ENGINE support too */
 149 static int bind_helper(ENGINE *e)
 150         {
 151 #ifndef OPENSSL_NO_RSA
 152         const RSA_METHOD *meth1;
 153 #endif
 154         if(!ENGINE_set_id(e, engine_e_gmp_id) ||
 155                         !ENGINE_set_name(e, engine_e_gmp_name) ||
 156 #ifndef OPENSSL_NO_RSA
 157                         !ENGINE_set_RSA(e, &e_gmp_rsa) ||
 158 #endif
 159                         !ENGINE_set_destroy_function(e, e_gmp_destroy) ||
 160                         !ENGINE_set_init_function(e, e_gmp_init) ||
 161                         !ENGINE_set_finish_function(e, e_gmp_finish) ||
 162                         !ENGINE_set_ctrl_function(e, e_gmp_ctrl) ||
 163                         !ENGINE_set_cmd_defns(e, e_gmp_cmd_defns))
 164                 return 0;
 165
 166 #ifndef OPENSSL_NO_RSA
 167         meth1 = RSA_PKCS1_SSLeay();
 168         e_gmp_rsa.rsa_pub_enc = meth1->rsa_pub_enc;
 169         e_gmp_rsa.rsa_pub_dec = meth1->rsa_pub_dec;
 170         e_gmp_rsa.rsa_priv_enc = meth1->rsa_priv_enc;
 171         e_gmp_rsa.rsa_priv_dec = meth1->rsa_priv_dec;
 172         e_gmp_rsa.bn_mod_exp = meth1->bn_mod_exp;
 173 #endif
 174
 175         /* Ensure the e_gmp error handling is set up */
 176         ERR_load_GMP_strings();
 177         return 1;
 178         }
 179
 180 static ENGINE *engine_gmp(void)
 181         {
 182         ENGINE *ret = ENGINE_new();
 183         if(!ret)
 184                 return NULL;
 185         if(!bind_helper(ret))
 186                 {
 187                 ENGINE_free(ret);
 188                 return NULL;
 189                 }
 190         return ret;
 191         }
 192
 193 void ENGINE_load_gmp(void)
 194         {
 195         /* Copied from eng_[openssl|dyn].c */
 196         ENGINE *toadd = engine_gmp();
 197         if(!toadd) return;
 198         ENGINE_add(toadd);
 199         ENGINE_free(toadd);
 200         ERR_clear_error();
 201         }
 202
 203 #ifndef OPENSSL_NO_RSA
 204 /* Used to attach our own key-data to an RSA structure */
 205 static int hndidx_rsa = -1;
 206 #endif
 207
 208 static int e_gmp_destroy(ENGINE *e)
 209         {
 210         ERR_unload_GMP_strings();
 211         return 1;
 212         }
 213
 214 /* (de)initialisation functions. */
 215 static int e_gmp_init(ENGINE *e)
 216         {
 217 #ifndef OPENSSL_NO_RSA
 218         if (hndidx_rsa == -1)
 219                 hndidx_rsa = RSA_get_ex_new_index(0,
 220                         "GMP-based RSA key handle",
 221                         NULL, NULL, NULL);
 222 #endif
 223         if (hndidx_rsa == -1)
 224                 return 0;
 225         return 1;
 226         }
 227
 228 static int e_gmp_finish(ENGINE *e)
 229         {
 230         return 1;
 231         }
 232
 233 static int e_gmp_ctrl(ENGINE *e, int cmd, long i, void *p, void (*f)(void))
 234         {
 235         int to_return = 1;
 236
 237         switch(cmd)
 238                 {
 239 #if 0
 240         case E_GMP_CMD_SO_PATH:
 241                 /* ... */
 242 #endif
 243         /* The command isn't understood by this engine */
 244         default:
 245                 GMPerr(GMP_F_E_GMP_CTRL,
 246                         GMP_R_CTRL_COMMAND_NOT_IMPLEMENTED);
 247                 to_return = 0;
 248                 break;
 249                 }
 250
 251         return to_return;
 252         }
 253
 254 /* HACK - use text I/O functions in openssl and GMP to handle conversions. This
 255  * is vile. */
 256 static int bn2gmp(const BIGNUM *bn, mpz_t g)
 257         {
 258         int toret;
 259         char *tmpchar = BN_bn2hex(bn);
 260         if(!tmpchar) return 0;
 261         toret = (mpz_set_str(g, tmpchar, 16) == 0 ? 1 : 0);
 262         OPENSSL_free(tmpchar);
 263         return toret;
 264         }
 265
 266 static int gmp2bn(mpz_t g, BIGNUM *bn)
 267         {
 268         int toret;
 269         char *tmpchar = OPENSSL_malloc(mpz_sizeinbase(g, 16) + 10);
 270         if(!tmpchar) return 0;
 271         mpz_get_str(tmpchar, 16, g);
 272         toret = BN_hex2bn(&bn, tmpchar);
 273         OPENSSL_free(tmpchar);
 274         return toret;
 275         }
 276
 277 #ifndef OPENSSL_NO_RSA
 278 typedef struct st_e_gmp_rsa_ctx
 279         {
 280         int public_only;
 281         mpz_t n;
 282         mpz_t d;
 283         mpz_t e;
 284         mpz_t p;
 285         mpz_t q;
 286         mpz_t dmp1;
 287         mpz_t dmq1;
 288         mpz_t iqmp;
 289         mpz_t r0, r1, I0, m1;
 290         } E_GMP_RSA_CTX;
 291
 292 static E_GMP_RSA_CTX *e_gmp_get_rsa(RSA *rsa)
 293         {
 294         E_GMP_RSA_CTX *hptr = RSA_get_ex_data(rsa, hndidx_rsa);
 295         if(hptr) return hptr;
 296         hptr = OPENSSL_malloc(sizeof(E_GMP_RSA_CTX));
 297         if(!hptr) return NULL;
 298         /* These inits could probably be replaced by more intelligent
 299          * mpz_init2() versions, to reduce malloc-thrashing. */
 300         mpz_init(hptr->n);
 301         mpz_init(hptr->d);
 302         mpz_init(hptr->e);
 303         mpz_init(hptr->p);
 304         mpz_init(hptr->q);
 305         mpz_init(hptr->dmp1);
 306         mpz_init(hptr->dmq1);
 307         mpz_init(hptr->iqmp);
 308         mpz_init(hptr->r0);
 309         mpz_init(hptr->r1);
 310         mpz_init(hptr->I0);
 311         mpz_init(hptr->m1);
 312         if(!bn2gmp(rsa->n, hptr->n) || !bn2gmp(rsa->e, hptr->e))
 313                 goto err;
 314         if(!rsa->p || !rsa->q || !rsa->d || !rsa->dmp1 || !rsa->dmq1 || !rsa->iqmp)
 315                 {
 316                 hptr->public_only = 1;
 317                 return hptr;
 318                 }
 319         if(!bn2gmp(rsa->d, hptr->d) || !bn2gmp(rsa->p, hptr->p) ||
 320                         !bn2gmp(rsa->q, hptr->q) || !bn2gmp(rsa->dmp1, hptr->dmp1) ||
 321                         !bn2gmp(rsa->dmq1, hptr->dmq1) || !bn2gmp(rsa->iqmp, hptr->iqmp))
 322                 goto err;
 323         hptr->public_only = 0;
 324         RSA_set_ex_data(rsa, hndidx_rsa, hptr);
 325         return hptr;
 326 err:
 327         mpz_clear(hptr->n);
 328         mpz_clear(hptr->d);
 329         mpz_clear(hptr->e);
 330         mpz_clear(hptr->p);
 331         mpz_clear(hptr->q);
 332         mpz_clear(hptr->dmp1);
 333         mpz_clear(hptr->dmq1);
 334         mpz_clear(hptr->iqmp);
 335         mpz_clear(hptr->r0);
 336         mpz_clear(hptr->r1);
 337         mpz_clear(hptr->I0);
 338         mpz_clear(hptr->m1);
 339         OPENSSL_free(hptr);
 340         return NULL;
 341         }
 342
 343 static int e_gmp_rsa_finish(RSA *rsa)
 344         {
 345         E_GMP_RSA_CTX *hptr = RSA_get_ex_data(rsa, hndidx_rsa);
 346         if(!hptr) return 0;
 347         mpz_clear(hptr->n);
 348         mpz_clear(hptr->d);
 349         mpz_clear(hptr->e);
 350         mpz_clear(hptr->p);
 351         mpz_clear(hptr->q);
 352         mpz_clear(hptr->dmp1);
 353         mpz_clear(hptr->dmq1);
 354         mpz_clear(hptr->iqmp);
 355         mpz_clear(hptr->r0);
 356         mpz_clear(hptr->r1);
 357         mpz_clear(hptr->I0);
 358         mpz_clear(hptr->m1);
 359         OPENSSL_free(hptr);
 360         RSA_set_ex_data(rsa, hndidx_rsa, NULL);
 361         return 1;
 362         }
 363
 364 static int e_gmp_rsa_mod_exp(BIGNUM *r, const BIGNUM *I, RSA *rsa, BN_CTX *ctx)
 365         {
 366         E_GMP_RSA_CTX *hptr;
 367         int to_return = 0;
 368
 369         hptr = e_gmp_get_rsa(rsa);
 370         if(!hptr)
 371                 {
 372                 GMPerr(GMP_F_E_GMP_RSA_MOD_EXP,
 373                                 GMP_R_KEY_CONTEXT_ERROR);
 374                 return 0;
 375                 }
 376         if(hptr->public_only)
 377                 {
 378                 GMPerr(GMP_F_E_GMP_RSA_MOD_EXP,
 379                                 GMP_R_MISSING_KEY_COMPONENTS);
 380                 return 0;
 381                 }
 382
 383         /* ugh!!! */
 384         if(!bn2gmp(I, hptr->I0))
 385                 return 0;
 386
 387         /* This is basically the CRT logic in crypto/rsa/rsa_eay.c reworded into
 388          * GMP-speak. It may be that GMP's API facilitates cleaner formulations
 389          * of this stuff, eg. better handling of negatives, or functions that
 390          * combine operations. */
 391
 392         mpz_mod(hptr->r1, hptr->I0, hptr->q);
 393         mpz_powm(hptr->m1, hptr->r1, hptr->dmq1, hptr->q);
 394
 395         mpz_mod(hptr->r1, hptr->I0, hptr->p);
 396         mpz_powm(hptr->r0, hptr->r1, hptr->dmp1, hptr->p);
 397
 398         mpz_sub(hptr->r0, hptr->r0, hptr->m1);
 399
 400         if(mpz_sgn(hptr->r0) < 0)
 401                 mpz_add(hptr->r0, hptr->r0, hptr->p);
 402         mpz_mul(hptr->r1, hptr->r0, hptr->iqmp);
 403         mpz_mod(hptr->r0, hptr->r1, hptr->p);
 404
 405         if(mpz_sgn(hptr->r0) < 0)
 406                 mpz_add(hptr->r0, hptr->r0, hptr->p);
 407         mpz_mul(hptr->r1, hptr->r0, hptr->q);
 408         mpz_add(hptr->r0, hptr->r1, hptr->m1);
 409
 410         /* ugh!!! */
 411         if(gmp2bn(hptr->r0, r))
 412                 to_return = 1;
 413
 414         return 1;
 415         }
 416 #endif
 417
 418 /* This stuff is needed if this ENGINE is being compiled into a self-contained
 419  * shared-library. */
 420 #ifdef ENGINE_DYNAMIC_SUPPORT
 421 static int bind_fn(ENGINE *e, const char *id)
 422         {
 423         if(id && (strcmp(id, engine_e_gmp_id) != 0))
 424                 return 0;
 425         if(!bind_helper(e))
 426                 return 0;
 427         return 1;
 428         }
 429 IMPLEMENT_DYNAMIC_CHECK_FN()
 430 IMPLEMENT_DYNAMIC_BIND_FN(bind_fn)
 431 #endif /* ENGINE_DYNAMIC_SUPPORT */
 432
 433 #endif /* !OPENSSL_NO_HW_GMP */
 434 #endif /* !OPENSSL_NO_HW */
 435