crypto/engine/engine_lib.c

   1 /* crypto/engine/engine_lib.c */
   2 /* Written by Geoff Thorpe (geoff@geoffthorpe.net) for the OpenSSL
   3  * project 2000.
   4  */
   5 /* ====================================================================
   6  * Copyright (c) 1999 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 #include <openssl/crypto.h>
  60 #include "cryptlib.h"
  61 #include "engine_int.h"
  62 #include <openssl/engine.h>
  63
  64 /* These pointers each have their own "functional reference" when they
  65  * are non-NULL. Similarly, when they are retrieved by a call to
  66  * ENGINE_get_default_[RSA|DSA|...] the returned pointer is also a
  67  * reference and the caller is responsible for freeing that when they
  68  * are finished with it (with a call to ENGINE_finish() *NOT* just
  69  * ENGINE_free()!!!!!!). */
  70 #ifndef OPENSSL_NO_RSA
  71 static ENGINE *engine_def_rsa = NULL;
  72 #endif
  73 #ifndef OPENSSL_NO_DSA
  74 static ENGINE *engine_def_dsa = NULL;
  75 #endif
  76 #ifndef OPENSSL_NO_DH
  77 static ENGINE *engine_def_dh = NULL;
  78 #endif
  79 static ENGINE *engine_def_rand = NULL;
  80 static ENGINE *engine_def_bn_mod_exp = NULL;
  81 static ENGINE *engine_def_bn_mod_exp_crt = NULL;
  82 /* A static "once-only" flag used to control if/when the above were
  83  * initialised to suitable start-up defaults. */
  84 static int engine_def_flag = 0;
  85
  86 /* When querying a ENGINE-specific control command's 'description', this string
  87  * is used if the ENGINE_CMD_DEFN has cmd_desc set to NULL. */
  88 static const char *int_no_description = "";
  89
  90 /* This is used in certain static utility functions to save code
  91  * repetition for per-algorithm functions. */
  92 typedef enum {
  93         ENGINE_TYPE_RSA,
  94         ENGINE_TYPE_DSA,
  95         ENGINE_TYPE_DH,
  96         ENGINE_TYPE_RAND,
  97         ENGINE_TYPE_BN_MOD_EXP,
  98         ENGINE_TYPE_BN_MOD_EXP_CRT
  99         } ENGINE_TYPE;
 100
 101 static void engine_def_check_util(ENGINE **def, ENGINE *val)
 102         {
 103         *def = val;
 104         val->struct_ref++;
 105         val->funct_ref++;
 106         }
 107
 108 /* In a slight break with convention - this static function must be
 109  * called *outside* any locking of CRYPTO_LOCK_ENGINE. */
 110 static void engine_def_check(void)
 111         {
 112         ENGINE *e;
 113         if(engine_def_flag)
 114                 return;
 115         e = ENGINE_get_first();
 116         if(e == NULL)
 117                 /* The list is empty ... not much we can do! */
 118                 return;
 119         /* We have a structural reference, see if getting a functional
 120          * reference is possible. This is done to cope with init errors
 121          * in the engine - the following locked code does a bunch of
 122          * manual "ENGINE_init"s which do *not* allow such an init
 123          * error so this is worth doing. */
 124         if(ENGINE_init(e))
 125                 {
 126                 CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 127                 /* Doing another check here prevents an obvious race
 128                  * condition because the whole function itself cannot
 129                  * be locked. */
 130                 if(engine_def_flag)
 131                         goto skip_set_defaults;
 132                 /* OK, we got a functional reference, so we get one each
 133                  * for the defaults too. */
 134 #ifndef OPENSSL_NO_RSA
 135                 engine_def_check_util(&engine_def_rsa, e);
 136 #endif
 137 #ifndef OPENSSL_NO_RSA
 138                 engine_def_check_util(&engine_def_dsa, e);
 139 #endif
 140 #ifndef OPENSSL_NO_DH
 141                 engine_def_check_util(&engine_def_dh, e);
 142 #endif
 143                 engine_def_check_util(&engine_def_rand, e);
 144                 engine_def_check_util(&engine_def_bn_mod_exp, e);
 145                 engine_def_check_util(&engine_def_bn_mod_exp_crt, e);
 146                 engine_def_flag = 1;
 147 skip_set_defaults:
 148                 CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 149                 /* The "if" needs to be balanced out. */
 150                 ENGINE_finish(e);
 151                 }
 152         /* We need to balance out the fact we obtained a structural
 153          * reference to begin with from ENGINE_get_first(). */
 154         ENGINE_free(e);
 155         }
 156
 157 /* Initialise a engine type for use (or up its functional reference count
 158  * if it's already in use). */
 159 int ENGINE_init(ENGINE *e)
 160         {
 161         int to_return = 1;
 162
 163         if(e == NULL)
 164                 {
 165                 ENGINEerr(ENGINE_F_ENGINE_INIT,ERR_R_PASSED_NULL_PARAMETER);
 166                 return 0;
 167                 }
 168         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 169         if((e->funct_ref == 0) && e->init)
 170                 /* This is the first functional reference and the engine
 171                  * requires initialisation so we do it now. */
 172                 to_return = e->init(e);
 173         if(to_return)
 174                 {
 175                 /* OK, we return a functional reference which is also a
 176                  * structural reference. */
 177                 e->struct_ref++;
 178                 e->funct_ref++;
 179                 }
 180         CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 181         return to_return;
 182         }
 183
 184 /* Free a functional reference to a engine type */
 185 int ENGINE_finish(ENGINE *e)
 186         {
 187         int to_return = 1;
 188
 189         if(e == NULL)
 190                 {
 191                 ENGINEerr(ENGINE_F_ENGINE_FINISH,ERR_R_PASSED_NULL_PARAMETER);
 192                 return 0;
 193                 }
 194         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 195         if((e->funct_ref == 1) && e->finish)
 196 #if 0
 197                 /* This is the last functional reference and the engine
 198                  * requires cleanup so we do it now. */
 199                 to_return = e->finish();
 200         if(to_return)
 201                 {
 202                 /* Cleanup the functional reference which is also a
 203                  * structural reference. */
 204                 e->struct_ref--;
 205                 e->funct_ref--;
 206                 }
 207         CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 208 #else
 209                 /* I'm going to deliberately do a convoluted version of this
 210                  * piece of code because we don't want "finish" functions
 211                  * being called inside a locked block of code, if at all
 212                  * possible. I'd rather have this call take an extra couple
 213                  * of ticks than have throughput serialised on a externally-
 214                  * provided callback function that may conceivably never come
 215                  * back. :-( */
 216                 {
 217                 CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 218                 /* CODE ALERT: This *IS* supposed to be "=" and NOT "==" :-) */
 219                 if((to_return = e->finish(e)))
 220                         {
 221                         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 222                         /* Cleanup the functional reference which is also a
 223                          * structural reference. */
 224                         e->struct_ref--;
 225                         e->funct_ref--;
 226                         CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 227                         }
 228                 }
 229         else
 230                 CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 231 #endif
 232         return to_return;
 233         }
 234
 235 EVP_PKEY *ENGINE_load_private_key(ENGINE *e, const char *key_id,
 236         const char *passphrase)
 237         {
 238         EVP_PKEY *pkey;
 239
 240         if(e == NULL)
 241                 {
 242                 ENGINEerr(ENGINE_F_ENGINE_LOAD_PRIVATE_KEY,
 243                         ERR_R_PASSED_NULL_PARAMETER);
 244                 return 0;
 245                 }
 246         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 247         if(e->funct_ref == 0)
 248                 {
 249                 CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 250                 ENGINEerr(ENGINE_F_ENGINE_LOAD_PRIVATE_KEY,
 251                         ENGINE_R_NOT_INITIALISED);
 252                 return 0;
 253                 }
 254         CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 255         if (!e->load_privkey)
 256                 {
 257                 ENGINEerr(ENGINE_F_ENGINE_LOAD_PRIVATE_KEY,
 258                         ENGINE_R_NO_LOAD_FUNCTION);
 259                 return 0;
 260                 }
 261         pkey = e->load_privkey(e, key_id, passphrase);
 262         if (!pkey)
 263                 {
 264                 ENGINEerr(ENGINE_F_ENGINE_LOAD_PRIVATE_KEY,
 265                         ENGINE_R_FAILED_LOADING_PRIVATE_KEY);
 266                 return 0;
 267                 }
 268         return pkey;
 269         }
 270
 271 EVP_PKEY *ENGINE_load_public_key(ENGINE *e, const char *key_id,
 272         const char *passphrase)
 273         {
 274         EVP_PKEY *pkey;
 275
 276         if(e == NULL)
 277                 {
 278                 ENGINEerr(ENGINE_F_ENGINE_LOAD_PUBLIC_KEY,
 279                         ERR_R_PASSED_NULL_PARAMETER);
 280                 return 0;
 281                 }
 282         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 283         if(e->funct_ref == 0)
 284                 {
 285                 CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 286                 ENGINEerr(ENGINE_F_ENGINE_LOAD_PUBLIC_KEY,
 287                         ENGINE_R_NOT_INITIALISED);
 288                 return 0;
 289                 }
 290         CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 291         if (!e->load_pubkey)
 292                 {
 293                 ENGINEerr(ENGINE_F_ENGINE_LOAD_PUBLIC_KEY,
 294                         ENGINE_R_NO_LOAD_FUNCTION);
 295                 return 0;
 296                 }
 297         pkey = e->load_pubkey(e, key_id, passphrase);
 298         if (!pkey)
 299                 {
 300                 ENGINEerr(ENGINE_F_ENGINE_LOAD_PUBLIC_KEY,
 301                         ENGINE_R_FAILED_LOADING_PUBLIC_KEY);
 302                 return 0;
 303                 }
 304         return pkey;
 305         }
 306
 307 /* These internal functions handle 'CMD'-related control commands when the
 308  * ENGINE in question has asked us to take care of it (ie. the ENGINE did not
 309  * set the ENGINE_FLAGS_MANUAL_CMD_CTRL flag. */
 310
 311 static int int_ctrl_cmd_is_null(const ENGINE_CMD_DEFN *defn)
 312         {
 313         if((defn->cmd_num == 0) || (defn->cmd_name == NULL))
 314                 return 1;
 315         return 0;
 316         }
 317
 318 static int int_ctrl_cmd_by_name(const ENGINE_CMD_DEFN *defn, const char *s)
 319         {
 320         int idx = 0;
 321         while(!int_ctrl_cmd_is_null(defn) && (strcmp(defn->cmd_name, s) != 0))
 322                 {
 323                 idx++;
 324                 defn++;
 325                 }
 326         if(int_ctrl_cmd_is_null(defn))
 327                 /* The given name wasn't found */
 328                 return -1;
 329         return idx;
 330         }
 331
 332 static int int_ctrl_cmd_by_num(const ENGINE_CMD_DEFN *defn, unsigned int num)
 333         {
 334         int idx = 0;
 335         /* NB: It is stipulated that 'cmd_defn' lists are ordered by cmd_num. So
 336          * our searches don't need to take any longer than necessary. */
 337         while(!int_ctrl_cmd_is_null(defn) && (defn->cmd_num < num))
 338                 {
 339                 idx++;
 340                 defn++;
 341                 }
 342         if(defn->cmd_num == num)
 343                 return idx;
 344         /* The given cmd_num wasn't found */
 345         return -1;
 346         }
 347
 348 static int int_ctrl_helper(ENGINE *e, int cmd, long i, void *p, void (*f)())
 349         {
 350         int idx;
 351         char *s = (char *)p;
 352         /* Take care of the easy one first (eg. it requires no searches) */
 353         if(cmd == ENGINE_CTRL_GET_FIRST_CMD_TYPE)
 354                 {
 355                 if((e->cmd_defns == NULL) || int_ctrl_cmd_is_null(e->cmd_defns))
 356                         return 0;
 357                 return e->cmd_defns->cmd_num;
 358                 }
 359         /* One or two commands require that "p" be a valid string buffer */
 360         if((cmd == ENGINE_CTRL_GET_CMD_FROM_NAME) ||
 361                         (cmd == ENGINE_CTRL_GET_NAME_FROM_CMD) ||
 362                         (cmd == ENGINE_CTRL_GET_DESC_FROM_CMD))
 363                 {
 364                 if(s == NULL)
 365                         {
 366                         ENGINEerr(ENGINE_F_INT_CTRL_HELPER,
 367                                 ERR_R_PASSED_NULL_PARAMETER);
 368                         return -1;
 369                         }
 370                 }
 371         /* Now handle cmd_name -> cmd_num conversion */
 372         if(cmd == ENGINE_CTRL_GET_CMD_FROM_NAME)
 373                 {
 374                 if((e->cmd_defns == NULL) || ((idx = int_ctrl_cmd_by_name(
 375                                                 e->cmd_defns, s)) < 0))
 376                         {
 377                         ENGINEerr(ENGINE_F_INT_CTRL_HELPER,
 378                                 ENGINE_R_INVALID_CMD_NAME);
 379                         return -1;
 380                         }
 381                 return e->cmd_defns[idx].cmd_num;
 382                 }
 383         /* For the rest of the commands, the 'long' argument must specify a
 384          * valie command number - so we need to conduct a search. */
 385         if((e->cmd_defns == NULL) || ((idx = int_ctrl_cmd_by_num(e->cmd_defns,
 386                                         (unsigned int)i)) < 0))
 387                 {
 388                 ENGINEerr(ENGINE_F_INT_CTRL_HELPER,
 389                         ENGINE_R_INVALID_CMD_NUMBER);
 390                 return -1;
 391                 }
 392         /* Now the logic splits depending on command type */
 393         switch(cmd)
 394                 {
 395         case ENGINE_CTRL_GET_NEXT_CMD_TYPE:
 396                 idx++;
 397                 if(int_ctrl_cmd_is_null(e->cmd_defns + idx))
 398                         /* end-of-list */
 399                         return 0;
 400                 else
 401                         return e->cmd_defns[idx].cmd_num;
 402         case ENGINE_CTRL_GET_NAME_LEN_FROM_CMD:
 403                 return strlen(e->cmd_defns[idx].cmd_name);
 404         case ENGINE_CTRL_GET_NAME_FROM_CMD:
 405                 return sprintf(s, "%s", e->cmd_defns[idx].cmd_name);
 406         case ENGINE_CTRL_GET_DESC_LEN_FROM_CMD:
 407                 if(e->cmd_defns[idx].cmd_desc)
 408                         return strlen(e->cmd_defns[idx].cmd_desc);
 409                 return strlen(int_no_description);
 410         case ENGINE_CTRL_GET_DESC_FROM_CMD:
 411                 if(e->cmd_defns[idx].cmd_desc)
 412                         return sprintf(s, "%s", e->cmd_defns[idx].cmd_desc);
 413                 return sprintf(s, "%s", int_no_description);
 414         case ENGINE_CTRL_GET_CMD_FLAGS:
 415                 return e->cmd_defns[idx].cmd_flags;
 416                 }
 417         /* Shouldn't really be here ... */
 418         ENGINEerr(ENGINE_F_INT_CTRL_HELPER,ENGINE_R_INTERNAL_LIST_ERROR);
 419         return -1;
 420         }
 421
 422 int ENGINE_ctrl(ENGINE *e, int cmd, long i, void *p, void (*f)())
 423         {
 424         int ctrl_exists, ref_exists;
 425         if(e == NULL)
 426                 {
 427                 ENGINEerr(ENGINE_F_ENGINE_CTRL,ERR_R_PASSED_NULL_PARAMETER);
 428                 return 0;
 429                 }
 430         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 431         ref_exists = ((e->struct_ref > 0) ? 1 : 0);
 432         CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 433         ctrl_exists = ((e->ctrl == NULL) ? 0 : 1);
 434         if(!ref_exists)
 435                 {
 436                 ENGINEerr(ENGINE_F_ENGINE_CTRL,ENGINE_R_NO_REFERENCE);
 437                 return 0;
 438                 }
 439         /* Intercept any "root-level" commands before trying to hand them on to
 440          * ctrl() handlers. */
 441         switch(cmd)
 442                 {
 443         case ENGINE_CTRL_HAS_CTRL_FUNCTION:
 444                 return ctrl_exists;
 445         case ENGINE_CTRL_GET_FIRST_CMD_TYPE:
 446         case ENGINE_CTRL_GET_NEXT_CMD_TYPE:
 447         case ENGINE_CTRL_GET_CMD_FROM_NAME:
 448         case ENGINE_CTRL_GET_NAME_LEN_FROM_CMD:
 449         case ENGINE_CTRL_GET_NAME_FROM_CMD:
 450         case ENGINE_CTRL_GET_DESC_LEN_FROM_CMD:
 451         case ENGINE_CTRL_GET_DESC_FROM_CMD:
 452         case ENGINE_CTRL_GET_CMD_FLAGS:
 453                 if(ctrl_exists && !(e->flags & ENGINE_FLAGS_MANUAL_CMD_CTRL))
 454                         return int_ctrl_helper(e,cmd,i,p,f);
 455                 if(!ctrl_exists)
 456                         {
 457                         ENGINEerr(ENGINE_F_ENGINE_CTRL,ENGINE_R_NO_CONTROL_FUNCTION);
 458                         /* For these cmd-related functions, failure is indicated
 459                          * by a -1 return value (because 0 is used as a valid
 460                          * return in some places). */
 461                         return -1;
 462                         }
 463         default:
 464                 break;
 465                 }
 466         /* Anything else requires a ctrl() handler to exist. */
 467         if(!ctrl_exists)
 468                 {
 469                 ENGINEerr(ENGINE_F_ENGINE_CTRL,ENGINE_R_NO_CONTROL_FUNCTION);
 470                 return 0;
 471                 }
 472         return e->ctrl(e, cmd, i, p, f);
 473         }
 474
 475 int ENGINE_cmd_is_executable(ENGINE *e, int cmd)
 476         {
 477         int flags;
 478         if((flags = ENGINE_ctrl(e, ENGINE_CTRL_GET_CMD_FLAGS, cmd, NULL, NULL)) < 0)
 479                 {
 480                 ENGINEerr(ENGINE_F_ENGINE_CMD_IS_EXECUTABLE,
 481                         ENGINE_R_INVALID_CMD_NUMBER);
 482                 return 0;
 483                 }
 484         if(!(flags & ENGINE_CMD_FLAG_NO_INPUT) &&
 485                         !(flags & ENGINE_CMD_FLAG_NUMERIC) &&
 486                         !(flags & ENGINE_CMD_FLAG_STRING))
 487                 return 0;
 488         return 1;
 489         }
 490
 491 int ENGINE_ctrl_cmd_string(ENGINE *e, const char *cmd_name, const char *arg,
 492                                 int cmd_optional)
 493         {
 494         int num, flags;
 495         long l;
 496         char *ptr;
 497         if((e == NULL) || (cmd_name == NULL))
 498                 {
 499                 ENGINEerr(ENGINE_F_ENGINE_CTRL_CMD_STRING,
 500                         ERR_R_PASSED_NULL_PARAMETER);
 501                 return 0;
 502                 }
 503         if((e->ctrl == NULL) || ((num = ENGINE_ctrl(e,
 504                                         ENGINE_CTRL_GET_CMD_FROM_NAME,
 505                                         0, (void *)cmd_name, NULL)) <= 0))
 506                 {
 507                 /* If the command didn't *have* to be supported, we fake
 508                  * success. This allows certain settings to be specified for
 509                  * multiple ENGINEs and only require a change of ENGINE id
 510                  * (without having to selectively apply settings). Eg. changing
 511                  * from a hardware device back to the regular software ENGINE
 512                  * without editing the config file, etc. */
 513                 if(cmd_optional)
 514                         {
 515                         ERR_clear_error();
 516                         return 1;
 517                         }
 518                 ENGINEerr(ENGINE_F_ENGINE_CTRL_CMD_STRING,
 519                         ENGINE_R_INVALID_CMD_NAME);
 520                 return 0;
 521                 }
 522         if(!ENGINE_cmd_is_executable(e, num))
 523                 {
 524                 ENGINEerr(ENGINE_F_ENGINE_CTRL_CMD_STRING,
 525                         ENGINE_R_CMD_NOT_EXECUTABLE);
 526                 return 0;
 527                 }
 528         if((flags = ENGINE_ctrl(e, ENGINE_CTRL_GET_CMD_FLAGS, num, NULL, NULL)) < 0)
 529                 {
 530                 /* Shouldn't happen, given that ENGINE_cmd_is_executable()
 531                  * returned success. */
 532                 ENGINEerr(ENGINE_F_ENGINE_CTRL_CMD_STRING,
 533                         ENGINE_R_INTERNAL_LIST_ERROR);
 534                 return 0;
 535                 }
 536         /* If the command takes no input, there must be no input. And vice
 537          * versa. */
 538         if(flags & ENGINE_CMD_FLAG_NO_INPUT)
 539                 {
 540                 if(arg != NULL)
 541                         {
 542                         ENGINEerr(ENGINE_F_ENGINE_CTRL_CMD_STRING,
 543                                 ENGINE_R_COMMAND_TAKES_NO_INPUT);
 544                         return 0;
 545                         }
 546                 /* We deliberately force the result of ENGINE_ctrl() to 0 or 1
 547                  * rather than returning it as "return data". This is to ensure
 548                  * usage of these commands is consistent across applications and
 549                  * that certain applications don't understand it one way, and
 550                  * others another. */
 551                 if(ENGINE_ctrl(e, num, 0, (void *)arg, NULL))
 552                         return 1;
 553                 return 0;
 554                 }
 555         /* So, we require input */
 556         if(arg == NULL)
 557                 {
 558                 ENGINEerr(ENGINE_F_ENGINE_CTRL_CMD_STRING,
 559                         ENGINE_R_COMMAND_TAKES_INPUT);
 560                 return 0;
 561                 }
 562         /* If it takes string input, that's easy */
 563         if(flags & ENGINE_CMD_FLAG_STRING)
 564                 {
 565                 /* Same explanation as above */
 566                 if(ENGINE_ctrl(e, num, 0, (void *)arg, NULL))
 567                         return 1;
 568                 return 0;
 569                 }
 570         /* If it doesn't take numeric either, then it is unsupported for use in
 571          * a config-setting situation, which is what this function is for. This
 572          * should never happen though, because ENGINE_cmd_is_executable() was
 573          * used. */
 574         if(!(flags & ENGINE_CMD_FLAG_NUMERIC))
 575                 {
 576                 ENGINEerr(ENGINE_F_ENGINE_CTRL_CMD_STRING,
 577                         ENGINE_R_INTERNAL_LIST_ERROR);
 578                 return 0;
 579                 }
 580         l = strtol(arg, &ptr, 10);
 581         if((arg == ptr) || (*ptr != '\0'))
 582                 {
 583                 ENGINEerr(ENGINE_F_ENGINE_CTRL_CMD_STRING,
 584                         ENGINE_R_ARGUMENT_IS_NOT_A_NUMBER);
 585                 return 0;
 586                 }
 587         /* Force the result of the control command to 0 or 1, for the reasons
 588          * mentioned before. */
 589         if(ENGINE_ctrl(e, num, l, NULL, NULL))
 590                 return 1;
 591         return 0;
 592         }
 593
 594 static ENGINE *engine_get_default_type(ENGINE_TYPE t)
 595         {
 596         ENGINE *ret = NULL;
 597
 598         /* engine_def_check is lean and mean and won't replace any
 599          * prior default engines ... so we must ensure that it is always
 600          * the first function to get to touch the default values. */
 601         engine_def_check();
 602         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 603         switch(t)
 604                 {
 605 #ifndef OPENSSL_NO_RSA
 606         case ENGINE_TYPE_RSA:
 607                 ret = engine_def_rsa; break;
 608 #endif
 609 #ifndef OPENSSL_NO_DSA
 610         case ENGINE_TYPE_DSA:
 611                 ret = engine_def_dsa; break;
 612 #endif
 613 #ifndef OPENSSL_NO_DH
 614         case ENGINE_TYPE_DH:
 615                 ret = engine_def_dh; break;
 616 #endif
 617         case ENGINE_TYPE_RAND:
 618                 ret = engine_def_rand; break;
 619         case ENGINE_TYPE_BN_MOD_EXP:
 620                 ret = engine_def_bn_mod_exp; break;
 621         case ENGINE_TYPE_BN_MOD_EXP_CRT:
 622                 ret = engine_def_bn_mod_exp_crt; break;
 623                 }
 624         /* Unforunately we can't do this work outside the lock with a
 625          * call to ENGINE_init() because that would leave a race
 626          * condition open. */
 627         if(ret)
 628                 {
 629                 ret->struct_ref++;
 630                 ret->funct_ref++;
 631                 }
 632         CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 633         return ret;
 634         }
 635
 636 #ifndef OPENSSL_NO_RSA
 637 ENGINE *ENGINE_get_default_RSA(void)
 638         {
 639         return engine_get_default_type(ENGINE_TYPE_RSA);
 640         }
 641 #endif
 642
 643 #ifndef OPENSSL_NO_DSA
 644 ENGINE *ENGINE_get_default_DSA(void)
 645         {
 646         return engine_get_default_type(ENGINE_TYPE_DSA);
 647         }
 648 #endif
 649
 650 #ifndef OPENSSL_NO_DH
 651 ENGINE *ENGINE_get_default_DH(void)
 652         {
 653         return engine_get_default_type(ENGINE_TYPE_DH);
 654         }
 655 #endif
 656
 657 ENGINE *ENGINE_get_default_RAND(void)
 658         {
 659         return engine_get_default_type(ENGINE_TYPE_RAND);
 660         }
 661
 662 ENGINE *ENGINE_get_default_BN_mod_exp(void)
 663         {
 664         return engine_get_default_type(ENGINE_TYPE_BN_MOD_EXP);
 665         }
 666
 667 ENGINE *ENGINE_get_default_BN_mod_exp_crt(void)
 668         {
 669         return engine_get_default_type(ENGINE_TYPE_BN_MOD_EXP_CRT);
 670         }
 671
 672 static int engine_set_default_type(ENGINE_TYPE t, ENGINE *e)
 673         {
 674         ENGINE *old = NULL;
 675
 676         if(e == NULL)
 677                 {
 678                 ENGINEerr(ENGINE_F_ENGINE_SET_DEFAULT_TYPE,
 679                         ERR_R_PASSED_NULL_PARAMETER);
 680                 return 0;
 681                 }
 682         /* engine_def_check is lean and mean and won't replace any
 683          * prior default engines ... so we must ensure that it is always
 684          * the first function to get to touch the default values. */
 685         engine_def_check();
 686         /* Attempt to get a functional reference (we need one anyway, but
 687          * also, 'e' may be just a structural reference being passed in so
 688          * this call may actually be the first). */
 689         if(!ENGINE_init(e))
 690                 {
 691                 ENGINEerr(ENGINE_F_ENGINE_SET_DEFAULT_TYPE,
 692                         ENGINE_R_INIT_FAILED);
 693                 return 0;
 694                 }
 695         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 696         switch(t)
 697                 {
 698 #ifndef OPENSSL_NO_RSA
 699         case ENGINE_TYPE_RSA:
 700                 old = engine_def_rsa;
 701                 engine_def_rsa = e; break;
 702 #endif
 703 #ifndef OPENSSL_NO_DSA
 704         case ENGINE_TYPE_DSA:
 705                 old = engine_def_dsa;
 706                 engine_def_dsa = e; break;
 707 #endif
 708 #ifndef OPENSSL_NO_DH
 709         case ENGINE_TYPE_DH:
 710                 old = engine_def_dh;
 711                 engine_def_dh = e; break;
 712 #endif
 713         case ENGINE_TYPE_RAND:
 714                 old = engine_def_rand;
 715                 engine_def_rand = e; break;
 716         case ENGINE_TYPE_BN_MOD_EXP:
 717                 old = engine_def_bn_mod_exp;
 718                 engine_def_bn_mod_exp = e; break;
 719         case ENGINE_TYPE_BN_MOD_EXP_CRT:
 720                 old = engine_def_bn_mod_exp_crt;
 721                 engine_def_bn_mod_exp_crt = e; break;
 722                 }
 723         CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 724         /* If we've replaced a previous value, then we need to remove the
 725          * functional reference we had. */
 726         if(old && !ENGINE_finish(old))
 727                 {
 728                 ENGINEerr(ENGINE_F_ENGINE_SET_DEFAULT_TYPE,
 729                         ENGINE_R_FINISH_FAILED);
 730                 return 0;
 731                 }
 732         return 1;
 733         }
 734
 735 #ifndef OPENSSL_NO_RSA
 736 int ENGINE_set_default_RSA(ENGINE *e)
 737         {
 738         return engine_set_default_type(ENGINE_TYPE_RSA, e);
 739         }
 740 #endif
 741
 742 #ifndef OPENSSL_NO_DSA
 743 int ENGINE_set_default_DSA(ENGINE *e)
 744         {
 745         return engine_set_default_type(ENGINE_TYPE_DSA, e);
 746         }
 747 #endif
 748
 749 #ifndef OPENSSL_NO_DH
 750 int ENGINE_set_default_DH(ENGINE *e)
 751         {
 752         return engine_set_default_type(ENGINE_TYPE_DH, e);
 753         }
 754 #endif
 755
 756 int ENGINE_set_default_RAND(ENGINE *e)
 757         {
 758         return engine_set_default_type(ENGINE_TYPE_RAND, e);
 759         }
 760
 761 int ENGINE_set_default_BN_mod_exp(ENGINE *e)
 762         {
 763         return engine_set_default_type(ENGINE_TYPE_BN_MOD_EXP, e);
 764         }
 765
 766 int ENGINE_set_default_BN_mod_exp_crt(ENGINE *e)
 767         {
 768         return engine_set_default_type(ENGINE_TYPE_BN_MOD_EXP_CRT, e);
 769         }
 770
 771 int ENGINE_set_default(ENGINE *e, unsigned int flags)
 772         {
 773 #ifndef OPENSSL_NO_RSA
 774         if((flags & ENGINE_METHOD_RSA) && e->rsa_meth &&
 775                         !ENGINE_set_default_RSA(e))
 776                 return 0;
 777 #endif
 778 #ifndef OPENSSL_NO_DSA
 779         if((flags & ENGINE_METHOD_DSA) && e->dsa_meth &&
 780                         !ENGINE_set_default_DSA(e))
 781                 return 0;
 782 #endif
 783 #ifndef OPENSSL_NO_DH
 784         if((flags & ENGINE_METHOD_DH) && e->dh_meth &&
 785                         !ENGINE_set_default_DH(e))
 786                 return 0;
 787 #endif
 788         if((flags & ENGINE_METHOD_RAND) && e->rand_meth &&
 789                         !ENGINE_set_default_RAND(e))
 790                 return 0;
 791         if((flags & ENGINE_METHOD_BN_MOD_EXP) && e->bn_mod_exp &&
 792                         !ENGINE_set_default_BN_mod_exp(e))
 793                 return 0;
 794         if((flags & ENGINE_METHOD_BN_MOD_EXP_CRT) && e->bn_mod_exp_crt &&
 795                         !ENGINE_set_default_BN_mod_exp_crt(e))
 796                 return 0;
 797         return 1;
 798         }
 799