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 105static int e_gmp_destroy(ENGINE *e); 106static int e_gmp_init(ENGINE *e); 107static int e_gmp_finish(ENGINE *e); 108static int e_gmp_ctrl(ENGINE *e, int cmd, long i, void *p, void (*f) (void)); 109 110# ifndef OPENSSL_NO_RSA 111/* RSA stuff */ 112static int e_gmp_rsa_mod_exp(BIGNUM *r, const BIGNUM *I, RSA *rsa, 113 BN_CTX *ctx); 114static 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 */ 119static 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 */ 131static 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 */ 154static const char *engine_e_gmp_id = "gmp"; 155static 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 */ 161static 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 192static 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 204void 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 */ 217static int hndidx_rsa = -1; 218# endif 219 220static int e_gmp_destroy(ENGINE *e) 221{ 222 ERR_unload_GMP_strings(); 223 return 1; 224} 225 226/* (de)initialisation functions. */ 227static 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 240static int e_gmp_finish(ENGINE *e) 241{ 242 return 1; 243} 244 245static 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 */ 268static 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 292static 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 319typedef 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 332static 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 387static 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 409static 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 469IMPLEMENT_DYNAMIC_CHECK_FN() 470# ifndef OPENSSL_NO_GMP 471static 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 480IMPLEMENT_DYNAMIC_BIND_FN(bind_fn) 481# else 482OPENSSL_EXPORT 483 int bind_engine(ENGINE *e, const char *id, const dynamic_fns *fns); 484OPENSSL_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 */ 493