crypto/engine/eng_list.c

   1 /* crypto/engine/eng_list.c */
   2 /* Written by Geoff Thorpe (geoff@geoffthorpe.net) for the OpenSSL
   3  * project 2000.
   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 #include <openssl/crypto.h>
  60 #include "cryptlib.h"
  61 #include "eng_int.h"
  62 #include <openssl/engine.h>
  63
  64 /* The linked-list of pointers to engine types. engine_list_head
  65  * incorporates an implicit structural reference but engine_list_tail
  66  * does not - the latter is a computational niceity and only points
  67  * to something that is already pointed to by its predecessor in the
  68  * list (or engine_list_head itself). In the same way, the use of the
  69  * "prev" pointer in each ENGINE is to save excessive list iteration,
  70  * it doesn't correspond to an extra structural reference. Hence,
  71  * engine_list_head, and each non-null "next" pointer account for
  72  * the list itself assuming exactly 1 structural reference on each
  73  * list member. */
  74 static ENGINE *engine_list_head = NULL;
  75 static ENGINE *engine_list_tail = NULL;
  76
  77 /* This cleanup function is only needed internally. If it should be called, we
  78  * register it with the "ENGINE_cleanup()" stack to be called during cleanup. */
  79
  80 static void engine_list_cleanup(void)
  81         {
  82         ENGINE *iterator = engine_list_head;
  83
  84         while(iterator != NULL)
  85                 {
  86                 ENGINE_remove(iterator);
  87                 iterator = engine_list_head;
  88                 }
  89         return;
  90         }
  91
  92 /* These static functions starting with a lower case "engine_" always
  93  * take place when CRYPTO_LOCK_ENGINE has been locked up. */
  94 static int engine_list_add(ENGINE *e)
  95         {
  96         int conflict = 0;
  97         ENGINE *iterator = NULL;
  98
  99         if(e == NULL)
 100                 {
 101                 ENGINEerr(ENGINE_F_ENGINE_LIST_ADD,
 102                         ERR_R_PASSED_NULL_PARAMETER);
 103                 return 0;
 104                 }
 105         iterator = engine_list_head;
 106         while(iterator && !conflict)
 107                 {
 108                 conflict = (strcmp(iterator->id, e->id) == 0);
 109                 iterator = iterator->next;
 110                 }
 111         if(conflict)
 112                 {
 113                 ENGINEerr(ENGINE_F_ENGINE_LIST_ADD,
 114                         ENGINE_R_CONFLICTING_ENGINE_ID);
 115                 return 0;
 116                 }
 117         if(engine_list_head == NULL)
 118                 {
 119                 /* We are adding to an empty list. */
 120                 if(engine_list_tail)
 121                         {
 122                         ENGINEerr(ENGINE_F_ENGINE_LIST_ADD,
 123                                 ENGINE_R_INTERNAL_LIST_ERROR);
 124                         return 0;
 125                         }
 126                 engine_list_head = e;
 127                 e->prev = NULL;
 128                 /* The first time the list allocates, we should register the
 129                  * cleanup. */
 130                 engine_cleanup_add_last(engine_list_cleanup);
 131                 }
 132         else
 133                 {
 134                 /* We are adding to the tail of an existing list. */
 135                 if((engine_list_tail == NULL) ||
 136                                 (engine_list_tail->next != NULL))
 137                         {
 138                         ENGINEerr(ENGINE_F_ENGINE_LIST_ADD,
 139                                 ENGINE_R_INTERNAL_LIST_ERROR);
 140                         return 0;
 141                         }
 142                 engine_list_tail->next = e;
 143                 e->prev = engine_list_tail;
 144                 }
 145         /* Having the engine in the list assumes a structural
 146          * reference. */
 147         e->struct_ref++;
 148         engine_ref_debug(e, 0, 1)
 149         /* However it came to be, e is the last item in the list. */
 150         engine_list_tail = e;
 151         e->next = NULL;
 152         return 1;
 153         }
 154
 155 static int engine_list_remove(ENGINE *e)
 156         {
 157         ENGINE *iterator;
 158
 159         if(e == NULL)
 160                 {
 161                 ENGINEerr(ENGINE_F_ENGINE_LIST_REMOVE,
 162                         ERR_R_PASSED_NULL_PARAMETER);
 163                 return 0;
 164                 }
 165         /* We need to check that e is in our linked list! */
 166         iterator = engine_list_head;
 167         while(iterator && (iterator != e))
 168                 iterator = iterator->next;
 169         if(iterator == NULL)
 170                 {
 171                 ENGINEerr(ENGINE_F_ENGINE_LIST_REMOVE,
 172                         ENGINE_R_ENGINE_IS_NOT_IN_LIST);
 173                 return 0;
 174                 }
 175         /* un-link e from the chain. */
 176         if(e->next)
 177                 e->next->prev = e->prev;
 178         if(e->prev)
 179                 e->prev->next = e->next;
 180         /* Correct our head/tail if necessary. */
 181         if(engine_list_head == e)
 182                 engine_list_head = e->next;
 183         if(engine_list_tail == e)
 184                 engine_list_tail = e->prev;
 185         engine_free_util(e, 0);
 186         return 1;
 187         }
 188
 189 /* Get the first/last "ENGINE" type available. */
 190 ENGINE *ENGINE_get_first(void)
 191         {
 192         ENGINE *ret;
 193
 194         CRYPTO_r_lock(CRYPTO_LOCK_ENGINE);
 195         ret = engine_list_head;
 196         if(ret)
 197                 {
 198                 ret->struct_ref++;
 199                 engine_ref_debug(ret, 0, 1)
 200                 }
 201         CRYPTO_r_unlock(CRYPTO_LOCK_ENGINE);
 202         return ret;
 203         }
 204
 205 ENGINE *ENGINE_get_last(void)
 206         {
 207         ENGINE *ret;
 208
 209         CRYPTO_r_lock(CRYPTO_LOCK_ENGINE);
 210                 ret = engine_list_tail;
 211         if(ret)
 212                 {
 213                 ret->struct_ref++;
 214                 engine_ref_debug(ret, 0, 1)
 215                 }
 216         CRYPTO_r_unlock(CRYPTO_LOCK_ENGINE);
 217         return ret;
 218         }
 219
 220 /* Iterate to the next/previous "ENGINE" type (NULL = end of the list). */
 221 ENGINE *ENGINE_get_next(ENGINE *e)
 222         {
 223         ENGINE *ret = NULL;
 224         if(e == NULL)
 225                 {
 226                 ENGINEerr(ENGINE_F_ENGINE_GET_NEXT,
 227                         ERR_R_PASSED_NULL_PARAMETER);
 228                 return 0;
 229                 }
 230         CRYPTO_r_lock(CRYPTO_LOCK_ENGINE);
 231         ret = e->next;
 232         if(ret)
 233                 {
 234                 /* Return a valid structural refernce to the next ENGINE */
 235                 ret->struct_ref++;
 236                 engine_ref_debug(ret, 0, 1)
 237                 }
 238         CRYPTO_r_unlock(CRYPTO_LOCK_ENGINE);
 239         /* Release the structural reference to the previous ENGINE */
 240         ENGINE_free(e);
 241         return ret;
 242         }
 243
 244 ENGINE *ENGINE_get_prev(ENGINE *e)
 245         {
 246         ENGINE *ret = NULL;
 247         if(e == NULL)
 248                 {
 249                 ENGINEerr(ENGINE_F_ENGINE_GET_PREV,
 250                         ERR_R_PASSED_NULL_PARAMETER);
 251                 return 0;
 252                 }
 253         CRYPTO_r_lock(CRYPTO_LOCK_ENGINE);
 254         ret = e->prev;
 255         if(ret)
 256                 {
 257                 /* Return a valid structural reference to the next ENGINE */
 258                 ret->struct_ref++;
 259                 engine_ref_debug(ret, 0, 1)
 260                 }
 261         CRYPTO_r_unlock(CRYPTO_LOCK_ENGINE);
 262         /* Release the structural reference to the previous ENGINE */
 263         ENGINE_free(e);
 264         return ret;
 265         }
 266
 267 /* Add another "ENGINE" type into the list. */
 268 int ENGINE_add(ENGINE *e)
 269         {
 270         int to_return = 1;
 271         if(e == NULL)
 272                 {
 273                 ENGINEerr(ENGINE_F_ENGINE_ADD,
 274                         ERR_R_PASSED_NULL_PARAMETER);
 275                 return 0;
 276                 }
 277         if((e->id == NULL) || (e->name == NULL))
 278                 {
 279                 ENGINEerr(ENGINE_F_ENGINE_ADD,
 280                         ENGINE_R_ID_OR_NAME_MISSING);
 281                 }
 282         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 283         if(!engine_list_add(e))
 284                 {
 285                 ENGINEerr(ENGINE_F_ENGINE_ADD,
 286                         ENGINE_R_INTERNAL_LIST_ERROR);
 287                 to_return = 0;
 288                 }
 289         CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 290         return to_return;
 291         }
 292
 293 /* Remove an existing "ENGINE" type from the array. */
 294 int ENGINE_remove(ENGINE *e)
 295         {
 296         int to_return = 1;
 297         if(e == NULL)
 298                 {
 299                 ENGINEerr(ENGINE_F_ENGINE_REMOVE,
 300                         ERR_R_PASSED_NULL_PARAMETER);
 301                 return 0;
 302                 }
 303         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 304         if(!engine_list_remove(e))
 305                 {
 306                 ENGINEerr(ENGINE_F_ENGINE_REMOVE,
 307                         ENGINE_R_INTERNAL_LIST_ERROR);
 308                 to_return = 0;
 309                 }
 310         CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 311         return to_return;
 312         }
 313
 314 static void engine_cpy(ENGINE *dest, const ENGINE *src)
 315         {
 316         dest->id = src->id;
 317         dest->name = src->name;
 318 #ifndef OPENSSL_NO_RSA
 319         dest->rsa_meth = src->rsa_meth;
 320 #endif
 321 #ifndef OPENSSL_NO_DSA
 322         dest->dsa_meth = src->dsa_meth;
 323 #endif
 324 #ifndef OPENSSL_NO_DH
 325         dest->dh_meth = src->dh_meth;
 326 #endif
 327 #ifndef OPENSSL_NO_ECDSA
 328         dest->ecdsa_meth = src->ecdsa_meth;
 329 #endif
 330         dest->rand_meth = src->rand_meth;
 331         dest->ciphers = src->ciphers;
 332         dest->digests = src->digests;
 333         dest->destroy = src->destroy;
 334         dest->init = src->init;
 335         dest->finish = src->finish;
 336         dest->ctrl = src->ctrl;
 337         dest->load_privkey = src->load_privkey;
 338         dest->load_pubkey = src->load_pubkey;
 339         dest->cmd_defns = src->cmd_defns;
 340         dest->flags = src->flags;
 341         }
 342
 343 ENGINE *ENGINE_by_id(const char *id)
 344         {
 345         ENGINE *iterator;
 346         if(id == NULL)
 347                 {
 348                 ENGINEerr(ENGINE_F_ENGINE_BY_ID,
 349                         ERR_R_PASSED_NULL_PARAMETER);
 350                 return NULL;
 351                 }
 352         CRYPTO_r_lock(CRYPTO_LOCK_ENGINE);
 353         iterator = engine_list_head;
 354         while(iterator && (strcmp(id, iterator->id) != 0))
 355                 iterator = iterator->next;
 356         if(iterator)
 357                 {
 358                 /* We need to return a structural reference. If this is an
 359                  * ENGINE type that returns copies, make a duplicate - otherwise
 360                  * increment the existing ENGINE's reference count. */
 361                 if(iterator->flags & ENGINE_FLAGS_BY_ID_COPY)
 362                         {
 363                         ENGINE *cp = ENGINE_new();
 364                         if(!cp)
 365                                 iterator = NULL;
 366                         else
 367                                 {
 368                                 engine_cpy(cp, iterator);
 369                                 iterator = cp;
 370                                 }
 371                         }
 372                 else
 373                         {
 374                         iterator->struct_ref++;
 375                         engine_ref_debug(iterator, 0, 1)
 376                         }
 377                 }
 378         CRYPTO_r_unlock(CRYPTO_LOCK_ENGINE);
 379         if(iterator == NULL)
 380                 {
 381                 ENGINEerr(ENGINE_F_ENGINE_BY_ID,
 382                         ENGINE_R_NO_SUCH_ENGINE);
 383                 ERR_add_error_data(2, "id=", id);
 384                 }
 385         return iterator;
 386         }