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         engine_ref_debug(val, 0, 1)
 107         engine_ref_debug(val, 1, 1)
 108         }
 109
 110 /* In a slight break with convention - this static function must be
 111  * called *outside* any locking of CRYPTO_LOCK_ENGINE. */
 112 static void engine_def_check(void)
 113         {
 114         ENGINE *e;
 115         if(engine_def_flag)
 116                 return;
 117         e = ENGINE_get_first();
 118         if(e == NULL)
 119                 /* The list is empty ... not much we can do! */
 120                 return;
 121         /* We have a structural reference, see if getting a functional
 122          * reference is possible. This is done to cope with init errors
 123          * in the engine - the following locked code does a bunch of
 124          * manual "ENGINE_init"s which do *not* allow such an init
 125          * error so this is worth doing. */
 126         if(ENGINE_init(e))
 127                 {
 128                 CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 129                 /* Doing another check here prevents an obvious race
 130                  * condition because the whole function itself cannot
 131                  * be locked. */
 132                 if(engine_def_flag)
 133                         goto skip_set_defaults;
 134                 /* OK, we got a functional reference, so we get one each
 135                  * for the defaults too. */
 136 #ifndef OPENSSL_NO_RSA
 137                 engine_def_check_util(&engine_def_rsa, e);
 138 #endif
 139 #ifndef OPENSSL_NO_DSA
 140                 engine_def_check_util(&engine_def_dsa, e);
 141 #endif
 142 #ifndef OPENSSL_NO_DH
 143                 engine_def_check_util(&engine_def_dh, e);
 144 #endif
 145                 engine_def_check_util(&engine_def_rand, e);
 146                 engine_def_check_util(&engine_def_bn_mod_exp, e);
 147                 engine_def_check_util(&engine_def_bn_mod_exp_crt, e);
 148                 engine_def_flag = 1;
 149 skip_set_defaults:
 150                 CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 151                 /* The "if" needs to be balanced out. */
 152                 ENGINE_finish(e);
 153                 }
 154         /* We need to balance out the fact we obtained a structural
 155          * reference to begin with from ENGINE_get_first(). */
 156         ENGINE_free(e);
 157         }
 158
 159 /* Initialise a engine type for use (or up its functional reference count
 160  * if it's already in use). */
 161 int ENGINE_init(ENGINE *e)
 162         {
 163         int to_return = 1;
 164
 165         if(e == NULL)
 166                 {
 167                 ENGINEerr(ENGINE_F_ENGINE_INIT,ERR_R_PASSED_NULL_PARAMETER);
 168                 return 0;
 169                 }
 170         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 171         if((e->funct_ref == 0) && e->init)
 172                 /* This is the first functional reference and the engine
 173                  * requires initialisation so we do it now. */
 174                 to_return = e->init(e);
 175         if(to_return)
 176                 {
 177                 /* OK, we return a functional reference which is also a
 178                  * structural reference. */
 179                 e->struct_ref++;
 180                 e->funct_ref++;
 181                 engine_ref_debug(e, 0, 1)
 182                 engine_ref_debug(e, 1, 1)
 183                 }
 184         CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 185         return to_return;
 186         }
 187
 188 /* Free a functional reference to a engine type */
 189 int ENGINE_finish(ENGINE *e)
 190         {
 191         int to_return = 1;
 192
 193         if(e == NULL)
 194                 {
 195                 ENGINEerr(ENGINE_F_ENGINE_FINISH,ERR_R_PASSED_NULL_PARAMETER);
 196                 return 0;
 197                 }
 198         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 199         /* Reduce the functional reference count here so if it's the terminating
 200          * case, we can release the lock safely and call the finish() handler
 201          * without risk of a race. We get a race if we leave the count until
 202          * after and something else is calling "finish" at the same time -
 203          * there's a chance that both threads will together take the count from
 204          * 2 to 0 without either calling finish(). */
 205         e->funct_ref--;
 206         engine_ref_debug(e, 1, -1)
 207         if((e->funct_ref == 0) && e->finish)
 208                 {
 209                 CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 210                 if(!(to_return = e->finish(e)))
 211                         {
 212                         ENGINEerr(ENGINE_F_ENGINE_FINISH,ENGINE_R_FINISH_FAILED);
 213                         return 0;
 214                         }
 215                 }
 216         else
 217                 CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 218 #ifdef REF_CHECK
 219         if(e->funct_ref < 0)
 220                 {
 221                 fprintf(stderr,"ENGINE_finish, bad functional reference count\n");
 222                 abort();
 223                 }
 224 #endif
 225         /* Release the structural reference too */
 226         if(!ENGINE_free(e))
 227                 {
 228                 ENGINEerr(ENGINE_F_ENGINE_FINISH,ENGINE_R_FINISH_FAILED);
 229                 return 0;
 230                 }
 231         return to_return;
 232         }
 233
 234 EVP_PKEY *ENGINE_load_private_key(ENGINE *e, const char *key_id,
 235         UI_METHOD *ui_method, void *callback_data)
 236         {
 237         EVP_PKEY *pkey;
 238
 239         if(e == NULL)
 240                 {
 241                 ENGINEerr(ENGINE_F_ENGINE_LOAD_PRIVATE_KEY,
 242                         ERR_R_PASSED_NULL_PARAMETER);
 243                 return 0;
 244                 }
 245         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 246         if(e->funct_ref == 0)
 247                 {
 248                 CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 249                 ENGINEerr(ENGINE_F_ENGINE_LOAD_PRIVATE_KEY,
 250                         ENGINE_R_NOT_INITIALISED);
 251                 return 0;
 252                 }
 253         CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 254         if (!e->load_privkey)
 255                 {
 256                 ENGINEerr(ENGINE_F_ENGINE_LOAD_PRIVATE_KEY,
 257                         ENGINE_R_NO_LOAD_FUNCTION);
 258                 return 0;
 259                 }
 260         pkey = e->load_privkey(e, key_id, ui_method, callback_data);
 261         if (!pkey)
 262                 {
 263                 ENGINEerr(ENGINE_F_ENGINE_LOAD_PRIVATE_KEY,
 264                         ENGINE_R_FAILED_LOADING_PRIVATE_KEY);
 265                 return 0;
 266                 }
 267         return pkey;
 268         }
 269
 270 EVP_PKEY *ENGINE_load_public_key(ENGINE *e, const char *key_id,
 271         UI_METHOD *ui_method, void *callback_data)
 272         {
 273         EVP_PKEY *pkey;
 274
 275         if(e == NULL)
 276                 {
 277                 ENGINEerr(ENGINE_F_ENGINE_LOAD_PUBLIC_KEY,
 278                         ERR_R_PASSED_NULL_PARAMETER);
 279                 return 0;
 280                 }
 281         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 282         if(e->funct_ref == 0)
 283                 {
 284                 CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 285                 ENGINEerr(ENGINE_F_ENGINE_LOAD_PUBLIC_KEY,
 286                         ENGINE_R_NOT_INITIALISED);
 287                 return 0;
 288                 }
 289         CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 290         if (!e->load_pubkey)
 291                 {
 292                 ENGINEerr(ENGINE_F_ENGINE_LOAD_PUBLIC_KEY,
 293                         ENGINE_R_NO_LOAD_FUNCTION);
 294                 return 0;
 295                 }
 296         pkey = e->load_pubkey(e, key_id, ui_method, callback_data);
 297         if (!pkey)
 298                 {
 299                 ENGINEerr(ENGINE_F_ENGINE_LOAD_PUBLIC_KEY,
 300                         ENGINE_R_FAILED_LOADING_PUBLIC_KEY);
 301                 return 0;
 302                 }
 303         return pkey;
 304         }
 305
 306 /* These internal functions handle 'CMD'-related control commands when the
 307  * ENGINE in question has asked us to take care of it (ie. the ENGINE did not
 308  * set the ENGINE_FLAGS_MANUAL_CMD_CTRL flag. */
 309
 310 static int int_ctrl_cmd_is_null(const ENGINE_CMD_DEFN *defn)
 311         {
 312         if((defn->cmd_num == 0) || (defn->cmd_name == NULL))
 313                 return 1;
 314         return 0;
 315         }
 316
 317 static int int_ctrl_cmd_by_name(const ENGINE_CMD_DEFN *defn, const char *s)
 318         {
 319         int idx = 0;
 320         while(!int_ctrl_cmd_is_null(defn) && (strcmp(defn->cmd_name, s) != 0))
 321                 {
 322                 idx++;
 323                 defn++;
 324                 }
 325         if(int_ctrl_cmd_is_null(defn))
 326                 /* The given name wasn't found */
 327                 return -1;
 328         return idx;
 329         }
 330
 331 static int int_ctrl_cmd_by_num(const ENGINE_CMD_DEFN *defn, unsigned int num)
 332         {
 333         int idx = 0;
 334         /* NB: It is stipulated that 'cmd_defn' lists are ordered by cmd_num. So
 335          * our searches don't need to take any longer than necessary. */
 336         while(!int_ctrl_cmd_is_null(defn) && (defn->cmd_num < num))
 337                 {
 338                 idx++;
 339                 defn++;
 340                 }
 341         if(defn->cmd_num == num)
 342                 return idx;
 343         /* The given cmd_num wasn't found */
 344         return -1;
 345         }
 346
 347 static int int_ctrl_helper(ENGINE *e, int cmd, long i, void *p, void (*f)())
 348         {
 349         int idx;
 350         char *s = (char *)p;
 351         /* Take care of the easy one first (eg. it requires no searches) */
 352         if(cmd == ENGINE_CTRL_GET_FIRST_CMD_TYPE)
 353                 {
 354                 if((e->cmd_defns == NULL) || int_ctrl_cmd_is_null(e->cmd_defns))
 355                         return 0;
 356                 return e->cmd_defns->cmd_num;
 357                 }
 358         /* One or two commands require that "p" be a valid string buffer */
 359         if((cmd == ENGINE_CTRL_GET_CMD_FROM_NAME) ||
 360                         (cmd == ENGINE_CTRL_GET_NAME_FROM_CMD) ||
 361                         (cmd == ENGINE_CTRL_GET_DESC_FROM_CMD))
 362                 {
 363                 if(s == NULL)
 364                         {
 365                         ENGINEerr(ENGINE_F_INT_CTRL_HELPER,
 366                                 ERR_R_PASSED_NULL_PARAMETER);
 367                         return -1;
 368                         }
 369                 }
 370         /* Now handle cmd_name -> cmd_num conversion */
 371         if(cmd == ENGINE_CTRL_GET_CMD_FROM_NAME)
 372                 {
 373                 if((e->cmd_defns == NULL) || ((idx = int_ctrl_cmd_by_name(
 374                                                 e->cmd_defns, s)) < 0))
 375                         {
 376                         ENGINEerr(ENGINE_F_INT_CTRL_HELPER,
 377                                 ENGINE_R_INVALID_CMD_NAME);
 378                         return -1;
 379                         }
 380                 return e->cmd_defns[idx].cmd_num;
 381                 }
 382         /* For the rest of the commands, the 'long' argument must specify a
 383          * valie command number - so we need to conduct a search. */
 384         if((e->cmd_defns == NULL) || ((idx = int_ctrl_cmd_by_num(e->cmd_defns,
 385                                         (unsigned int)i)) < 0))
 386                 {
 387                 ENGINEerr(ENGINE_F_INT_CTRL_HELPER,
 388                         ENGINE_R_INVALID_CMD_NUMBER);
 389                 return -1;
 390                 }
 391         /* Now the logic splits depending on command type */
 392         switch(cmd)
 393                 {
 394         case ENGINE_CTRL_GET_NEXT_CMD_TYPE:
 395                 idx++;
 396                 if(int_ctrl_cmd_is_null(e->cmd_defns + idx))
 397                         /* end-of-list */
 398                         return 0;
 399                 else
 400                         return e->cmd_defns[idx].cmd_num;
 401         case ENGINE_CTRL_GET_NAME_LEN_FROM_CMD:
 402                 return strlen(e->cmd_defns[idx].cmd_name);
 403         case ENGINE_CTRL_GET_NAME_FROM_CMD:
 404                 return sprintf(s, "%s", e->cmd_defns[idx].cmd_name);
 405         case ENGINE_CTRL_GET_DESC_LEN_FROM_CMD:
 406                 if(e->cmd_defns[idx].cmd_desc)
 407                         return strlen(e->cmd_defns[idx].cmd_desc);
 408                 return strlen(int_no_description);
 409         case ENGINE_CTRL_GET_DESC_FROM_CMD:
 410                 if(e->cmd_defns[idx].cmd_desc)
 411                         return sprintf(s, "%s", e->cmd_defns[idx].cmd_desc);
 412                 return sprintf(s, "%s", int_no_description);
 413         case ENGINE_CTRL_GET_CMD_FLAGS:
 414                 return e->cmd_defns[idx].cmd_flags;
 415                 }
 416         /* Shouldn't really be here ... */
 417         ENGINEerr(ENGINE_F_INT_CTRL_HELPER,ENGINE_R_INTERNAL_LIST_ERROR);
 418         return -1;
 419         }
 420
 421 int ENGINE_ctrl(ENGINE *e, int cmd, long i, void *p, void (*f)())
 422         {
 423         int ctrl_exists, ref_exists;
 424         if(e == NULL)
 425                 {
 426                 ENGINEerr(ENGINE_F_ENGINE_CTRL,ERR_R_PASSED_NULL_PARAMETER);
 427                 return 0;
 428                 }
 429         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 430         ref_exists = ((e->struct_ref > 0) ? 1 : 0);
 431         CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 432         ctrl_exists = ((e->ctrl == NULL) ? 0 : 1);
 433         if(!ref_exists)
 434                 {
 435                 ENGINEerr(ENGINE_F_ENGINE_CTRL,ENGINE_R_NO_REFERENCE);
 436                 return 0;
 437                 }
 438         /* Intercept any "root-level" commands before trying to hand them on to
 439          * ctrl() handlers. */
 440         switch(cmd)
 441                 {
 442         case ENGINE_CTRL_HAS_CTRL_FUNCTION:
 443                 return ctrl_exists;
 444         case ENGINE_CTRL_GET_FIRST_CMD_TYPE:
 445         case ENGINE_CTRL_GET_NEXT_CMD_TYPE:
 446         case ENGINE_CTRL_GET_CMD_FROM_NAME:
 447         case ENGINE_CTRL_GET_NAME_LEN_FROM_CMD:
 448         case ENGINE_CTRL_GET_NAME_FROM_CMD:
 449         case ENGINE_CTRL_GET_DESC_LEN_FROM_CMD:
 450         case ENGINE_CTRL_GET_DESC_FROM_CMD:
 451         case ENGINE_CTRL_GET_CMD_FLAGS:
 452                 if(ctrl_exists && !(e->flags & ENGINE_FLAGS_MANUAL_CMD_CTRL))
 453                         return int_ctrl_helper(e,cmd,i,p,f);
 454                 if(!ctrl_exists)
 455                         {
 456                         ENGINEerr(ENGINE_F_ENGINE_CTRL,ENGINE_R_NO_CONTROL_FUNCTION);
 457                         /* For these cmd-related functions, failure is indicated
 458                          * by a -1 return value (because 0 is used as a valid
 459                          * return in some places). */
 460                         return -1;
 461                         }
 462         default:
 463                 break;
 464                 }
 465         /* Anything else requires a ctrl() handler to exist. */
 466         if(!ctrl_exists)
 467                 {
 468                 ENGINEerr(ENGINE_F_ENGINE_CTRL,ENGINE_R_NO_CONTROL_FUNCTION);
 469                 return 0;
 470                 }
 471         return e->ctrl(e, cmd, i, p, f);
 472         }
 473
 474 int ENGINE_cmd_is_executable(ENGINE *e, int cmd)
 475         {
 476         int flags;
 477         if((flags = ENGINE_ctrl(e, ENGINE_CTRL_GET_CMD_FLAGS, cmd, NULL, NULL)) < 0)
 478                 {
 479                 ENGINEerr(ENGINE_F_ENGINE_CMD_IS_EXECUTABLE,
 480                         ENGINE_R_INVALID_CMD_NUMBER);
 481                 return 0;
 482                 }
 483         if(!(flags & ENGINE_CMD_FLAG_NO_INPUT) &&
 484                         !(flags & ENGINE_CMD_FLAG_NUMERIC) &&
 485                         !(flags & ENGINE_CMD_FLAG_STRING))
 486                 return 0;
 487         return 1;
 488         }
 489
 490 int ENGINE_ctrl_cmd(ENGINE *e, const char *cmd_name,
 491         long i, void *p, void (*f)(), int cmd_optional)
 492         {
 493         int num;
 494
 495         if((e == NULL) || (cmd_name == NULL))
 496                 {
 497                 ENGINEerr(ENGINE_F_ENGINE_CTRL_CMD_STRING,
 498                         ERR_R_PASSED_NULL_PARAMETER);
 499                 return 0;
 500                 }
 501         if((e->ctrl == NULL) || ((num = ENGINE_ctrl(e,
 502                                         ENGINE_CTRL_GET_CMD_FROM_NAME,
 503                                         0, (void *)cmd_name, NULL)) <= 0))
 504                 {
 505                 /* If the command didn't *have* to be supported, we fake
 506                  * success. This allows certain settings to be specified for
 507                  * multiple ENGINEs and only require a change of ENGINE id
 508                  * (without having to selectively apply settings). Eg. changing
 509                  * from a hardware device back to the regular software ENGINE
 510                  * without editing the config file, etc. */
 511                 if(cmd_optional)
 512                         {
 513                         ERR_clear_error();
 514                         return 1;
 515                         }
 516                 ENGINEerr(ENGINE_F_ENGINE_CTRL_CMD,
 517                         ENGINE_R_INVALID_CMD_NAME);
 518                 return 0;
 519                 }
 520         /* Force the result of the control command to 0 or 1, for the reasons
 521          * mentioned before. */
 522         if (ENGINE_ctrl(e, num, i, p, f))
 523                 return 1;
 524         return 0;
 525         }
 526
 527 int ENGINE_ctrl_cmd_string(ENGINE *e, const char *cmd_name, const char *arg,
 528                                 int cmd_optional)
 529         {
 530         int num, flags;
 531         long l;
 532         char *ptr;
 533         if((e == NULL) || (cmd_name == NULL))
 534                 {
 535                 ENGINEerr(ENGINE_F_ENGINE_CTRL_CMD_STRING,
 536                         ERR_R_PASSED_NULL_PARAMETER);
 537                 return 0;
 538                 }
 539         if((e->ctrl == NULL) || ((num = ENGINE_ctrl(e,
 540                                         ENGINE_CTRL_GET_CMD_FROM_NAME,
 541                                         0, (void *)cmd_name, NULL)) <= 0))
 542                 {
 543                 /* If the command didn't *have* to be supported, we fake
 544                  * success. This allows certain settings to be specified for
 545                  * multiple ENGINEs and only require a change of ENGINE id
 546                  * (without having to selectively apply settings). Eg. changing
 547                  * from a hardware device back to the regular software ENGINE
 548                  * without editing the config file, etc. */
 549                 if(cmd_optional)
 550                         {
 551                         ERR_clear_error();
 552                         return 1;
 553                         }
 554                 ENGINEerr(ENGINE_F_ENGINE_CTRL_CMD_STRING,
 555                         ENGINE_R_INVALID_CMD_NAME);
 556                 return 0;
 557                 }
 558         if(!ENGINE_cmd_is_executable(e, num))
 559                 {
 560                 ENGINEerr(ENGINE_F_ENGINE_CTRL_CMD_STRING,
 561                         ENGINE_R_CMD_NOT_EXECUTABLE);
 562                 return 0;
 563                 }
 564         if((flags = ENGINE_ctrl(e, ENGINE_CTRL_GET_CMD_FLAGS, num, NULL, NULL)) < 0)
 565                 {
 566                 /* Shouldn't happen, given that ENGINE_cmd_is_executable()
 567                  * returned success. */
 568                 ENGINEerr(ENGINE_F_ENGINE_CTRL_CMD_STRING,
 569                         ENGINE_R_INTERNAL_LIST_ERROR);
 570                 return 0;
 571                 }
 572         /* If the command takes no input, there must be no input. And vice
 573          * versa. */
 574         if(flags & ENGINE_CMD_FLAG_NO_INPUT)
 575                 {
 576                 if(arg != NULL)
 577                         {
 578                         ENGINEerr(ENGINE_F_ENGINE_CTRL_CMD_STRING,
 579                                 ENGINE_R_COMMAND_TAKES_NO_INPUT);
 580                         return 0;
 581                         }
 582                 /* We deliberately force the result of ENGINE_ctrl() to 0 or 1
 583                  * rather than returning it as "return data". This is to ensure
 584                  * usage of these commands is consistent across applications and
 585                  * that certain applications don't understand it one way, and
 586                  * others another. */
 587                 if(ENGINE_ctrl(e, num, 0, (void *)arg, NULL))
 588                         return 1;
 589                 return 0;
 590                 }
 591         /* So, we require input */
 592         if(arg == NULL)
 593                 {
 594                 ENGINEerr(ENGINE_F_ENGINE_CTRL_CMD_STRING,
 595                         ENGINE_R_COMMAND_TAKES_INPUT);
 596                 return 0;
 597                 }
 598         /* If it takes string input, that's easy */
 599         if(flags & ENGINE_CMD_FLAG_STRING)
 600                 {
 601                 /* Same explanation as above */
 602                 if(ENGINE_ctrl(e, num, 0, (void *)arg, NULL))
 603                         return 1;
 604                 return 0;
 605                 }
 606         /* If it doesn't take numeric either, then it is unsupported for use in
 607          * a config-setting situation, which is what this function is for. This
 608          * should never happen though, because ENGINE_cmd_is_executable() was
 609          * used. */
 610         if(!(flags & ENGINE_CMD_FLAG_NUMERIC))
 611                 {
 612                 ENGINEerr(ENGINE_F_ENGINE_CTRL_CMD_STRING,
 613                         ENGINE_R_INTERNAL_LIST_ERROR);
 614                 return 0;
 615                 }
 616         l = strtol(arg, &ptr, 10);
 617         if((arg == ptr) || (*ptr != '\0'))
 618                 {
 619                 ENGINEerr(ENGINE_F_ENGINE_CTRL_CMD_STRING,
 620                         ENGINE_R_ARGUMENT_IS_NOT_A_NUMBER);
 621                 return 0;
 622                 }
 623         /* Force the result of the control command to 0 or 1, for the reasons
 624          * mentioned before. */
 625         if(ENGINE_ctrl(e, num, l, NULL, NULL))
 626                 return 1;
 627         return 0;
 628         }
 629
 630 static ENGINE *engine_get_default_type(ENGINE_TYPE t)
 631         {
 632         ENGINE *ret = NULL;
 633
 634         /* engine_def_check is lean and mean and won't replace any
 635          * prior default engines ... so we must ensure that it is always
 636          * the first function to get to touch the default values. */
 637         engine_def_check();
 638         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 639         switch(t)
 640                 {
 641 #ifndef OPENSSL_NO_RSA
 642         case ENGINE_TYPE_RSA:
 643                 ret = engine_def_rsa; break;
 644 #endif
 645 #ifndef OPENSSL_NO_DSA
 646         case ENGINE_TYPE_DSA:
 647                 ret = engine_def_dsa; break;
 648 #endif
 649 #ifndef OPENSSL_NO_DH
 650         case ENGINE_TYPE_DH:
 651                 ret = engine_def_dh; break;
 652 #endif
 653         case ENGINE_TYPE_RAND:
 654                 ret = engine_def_rand; break;
 655         case ENGINE_TYPE_BN_MOD_EXP:
 656                 ret = engine_def_bn_mod_exp; break;
 657         case ENGINE_TYPE_BN_MOD_EXP_CRT:
 658                 ret = engine_def_bn_mod_exp_crt; break;
 659         default:
 660                 break;
 661                 }
 662         /* Unforunately we can't do this work outside the lock with a
 663          * call to ENGINE_init() because that would leave a race
 664          * condition open. */
 665         if(ret)
 666                 {
 667                 ret->struct_ref++;
 668                 ret->funct_ref++;
 669                 engine_ref_debug(ret, 0, 1)
 670                 engine_ref_debug(ret, 1, 1)
 671                 }
 672         CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 673         return ret;
 674         }
 675
 676 #ifndef OPENSSL_NO_RSA
 677 ENGINE *ENGINE_get_default_RSA(void)
 678         {
 679         return engine_get_default_type(ENGINE_TYPE_RSA);
 680         }
 681 #endif
 682
 683 #ifndef OPENSSL_NO_DSA
 684 ENGINE *ENGINE_get_default_DSA(void)
 685         {
 686         return engine_get_default_type(ENGINE_TYPE_DSA);
 687         }
 688 #endif
 689
 690 #ifndef OPENSSL_NO_DH
 691 ENGINE *ENGINE_get_default_DH(void)
 692         {
 693         return engine_get_default_type(ENGINE_TYPE_DH);
 694         }
 695 #endif
 696
 697 ENGINE *ENGINE_get_default_RAND(void)
 698         {
 699         return engine_get_default_type(ENGINE_TYPE_RAND);
 700         }
 701
 702 ENGINE *ENGINE_get_default_BN_mod_exp(void)
 703         {
 704         return engine_get_default_type(ENGINE_TYPE_BN_MOD_EXP);
 705         }
 706
 707 ENGINE *ENGINE_get_default_BN_mod_exp_crt(void)
 708         {
 709         return engine_get_default_type(ENGINE_TYPE_BN_MOD_EXP_CRT);
 710         }
 711
 712 static int engine_set_default_type(ENGINE_TYPE t, ENGINE *e)
 713         {
 714         ENGINE *old = NULL;
 715
 716         /* engine_def_check is lean and mean and won't replace any
 717          * prior default engines ... so we must ensure that it is always
 718          * the first function to get to touch the default values. */
 719         engine_def_check();
 720         /* Attempt to get a functional reference (we need one anyway, but
 721          * also, 'e' may be just a structural reference being passed in so
 722          * this call may actually be the first). */
 723         if(e && !ENGINE_init(e))
 724                 {
 725                 ENGINEerr(ENGINE_F_ENGINE_SET_DEFAULT_TYPE,
 726                         ENGINE_R_INIT_FAILED);
 727                 return 0;
 728                 }
 729         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 730         switch(t)
 731                 {
 732 #ifndef OPENSSL_NO_RSA
 733         case ENGINE_TYPE_RSA:
 734                 old = engine_def_rsa;
 735                 engine_def_rsa = e; break;
 736 #endif
 737 #ifndef OPENSSL_NO_DSA
 738         case ENGINE_TYPE_DSA:
 739                 old = engine_def_dsa;
 740                 engine_def_dsa = e; break;
 741 #endif
 742 #ifndef OPENSSL_NO_DH
 743         case ENGINE_TYPE_DH:
 744                 old = engine_def_dh;
 745                 engine_def_dh = e; break;
 746 #endif
 747         case ENGINE_TYPE_RAND:
 748                 old = engine_def_rand;
 749                 engine_def_rand = e; break;
 750         case ENGINE_TYPE_BN_MOD_EXP:
 751                 old = engine_def_bn_mod_exp;
 752                 engine_def_bn_mod_exp = e; break;
 753         case ENGINE_TYPE_BN_MOD_EXP_CRT:
 754                 old = engine_def_bn_mod_exp_crt;
 755                 engine_def_bn_mod_exp_crt = e; break;
 756         default:
 757                 break;
 758                 }
 759         CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 760         /* If we've replaced a previous value, then we need to remove the
 761          * functional reference we had. */
 762         if(old && !ENGINE_finish(old))
 763                 {
 764                 ENGINEerr(ENGINE_F_ENGINE_SET_DEFAULT_TYPE,
 765                         ENGINE_R_FINISH_FAILED);
 766                 return 0;
 767                 }
 768         return 1;
 769         }
 770
 771 #ifndef OPENSSL_NO_RSA
 772 int ENGINE_set_default_RSA(ENGINE *e)
 773         {
 774         return engine_set_default_type(ENGINE_TYPE_RSA, e);
 775         }
 776 #endif
 777
 778 #ifndef OPENSSL_NO_DSA
 779 int ENGINE_set_default_DSA(ENGINE *e)
 780         {
 781         return engine_set_default_type(ENGINE_TYPE_DSA, e);
 782         }
 783 #endif
 784
 785 #ifndef OPENSSL_NO_DH
 786 int ENGINE_set_default_DH(ENGINE *e)
 787         {
 788         return engine_set_default_type(ENGINE_TYPE_DH, e);
 789         }
 790 #endif
 791
 792 int ENGINE_set_default_RAND(ENGINE *e)
 793         {
 794         return engine_set_default_type(ENGINE_TYPE_RAND, e);
 795         }
 796
 797 int ENGINE_set_default_BN_mod_exp(ENGINE *e)
 798         {
 799         return engine_set_default_type(ENGINE_TYPE_BN_MOD_EXP, e);
 800         }
 801
 802 int ENGINE_set_default_BN_mod_exp_crt(ENGINE *e)
 803         {
 804         return engine_set_default_type(ENGINE_TYPE_BN_MOD_EXP_CRT, e);
 805         }
 806
 807 int ENGINE_set_default(ENGINE *e, unsigned int flags)
 808         {
 809 #ifndef OPENSSL_NO_RSA
 810         if((flags & ENGINE_METHOD_RSA) && e->rsa_meth &&
 811                         !ENGINE_set_default_RSA(e))
 812                 return 0;
 813 #endif
 814 #ifndef OPENSSL_NO_DSA
 815         if((flags & ENGINE_METHOD_DSA) && e->dsa_meth &&
 816                         !ENGINE_set_default_DSA(e))
 817                 return 0;
 818 #endif
 819 #ifndef OPENSSL_NO_DH
 820         if((flags & ENGINE_METHOD_DH) && e->dh_meth &&
 821                         !ENGINE_set_default_DH(e))
 822                 return 0;
 823 #endif
 824         if((flags & ENGINE_METHOD_RAND) && e->rand_meth &&
 825                         !ENGINE_set_default_RAND(e))
 826                 return 0;
 827         if((flags & ENGINE_METHOD_BN_MOD_EXP) && e->bn_mod_exp &&
 828                         !ENGINE_set_default_BN_mod_exp(e))
 829                 return 0;
 830         if((flags & ENGINE_METHOD_BN_MOD_EXP_CRT) && e->bn_mod_exp_crt &&
 831                         !ENGINE_set_default_BN_mod_exp_crt(e))
 832                 return 0;
 833         return 1;
 834         }
 835
 836 int ENGINE_clear_defaults(void)
 837         {
 838         /* If the defaults haven't even been set yet, don't bother. Any kind of
 839          * "cleanup" has a kind of implicit race-condition if another thread is
 840          * trying to keep going, so we don't address that with locking. The
 841          * first ENGINE_set_default_*** call will actually *create* a standard
 842          * set of default ENGINEs (including init() and functional reference
 843          * counts aplenty) before the rest of this function undoes them all. So
 844          * save some hassle ... */
 845         if(!engine_def_flag)
 846                 return 1;
 847         if((0 == 1) ||
 848 #ifndef OPENSSL_NO_RSA
 849                         !ENGINE_set_default_RSA(NULL) ||
 850 #endif
 851 #ifndef OPENSSL_NO_DSA
 852                         !ENGINE_set_default_DSA(NULL) ||
 853 #endif
 854 #ifndef OPENSSL_NO_DH
 855                         !ENGINE_set_default_DH(NULL) ||
 856 #endif
 857                         !ENGINE_set_default_RAND(NULL) ||
 858                         !ENGINE_set_default_BN_mod_exp(NULL) ||
 859                         !ENGINE_set_default_BN_mod_exp_crt(NULL) ||
 860                         !RAND_set_rand_method(NULL))
 861                 return 0;
 862         return 1;
 863         }
 864