lib/libcrypto/engine/eng_list.c

   1 /* $OpenBSD: eng_list.c,v 1.22 2017/01/29 17:49:23 beck Exp $ */
   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  * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
  60  * ECDH support in OpenSSL originally developed by
  61  * SUN MICROSYSTEMS, INC., and contributed to the OpenSSL project.
  62  */
  63
  64 #include <string.h>
  65 #include <unistd.h>
  66
  67 #include <openssl/opensslconf.h>
  68
  69 #include <openssl/err.h>
  70
  71 #include "cryptlib.h"
  72 #include "eng_int.h"
  73
  74 /* The linked-list of pointers to engine types. engine_list_head
  75  * incorporates an implicit structural reference but engine_list_tail
  76  * does not - the latter is a computational niceity and only points
  77  * to something that is already pointed to by its predecessor in the
  78  * list (or engine_list_head itself). In the same way, the use of the
  79  * "prev" pointer in each ENGINE is to save excessive list iteration,
  80  * it doesn't correspond to an extra structural reference. Hence,
  81  * engine_list_head, and each non-null "next" pointer account for
  82  * the list itself assuming exactly 1 structural reference on each
  83  * list member. */
  84 static ENGINE *engine_list_head = NULL;
  85 static ENGINE *engine_list_tail = NULL;
  86
  87 /* This cleanup function is only needed internally. If it should be called, we
  88  * register it with the "ENGINE_cleanup()" stack to be called during cleanup. */
  89
  90 static void
  91 engine_list_cleanup(void)
  92 {
  93         ENGINE *iterator = engine_list_head;
  94
  95         while (iterator != NULL && ENGINE_remove(iterator))
  96                 iterator = engine_list_head;
  97 }
  98
  99 /* These static functions starting with a lower case "engine_" always
 100  * take place when CRYPTO_LOCK_ENGINE has been locked up. */
 101 static int
 102 engine_list_add(ENGINE *e)
 103 {
 104         int conflict = 0;
 105         ENGINE *iterator = NULL;
 106
 107         if (e == NULL) {
 108                 ENGINEerror(ERR_R_PASSED_NULL_PARAMETER);
 109                 return 0;
 110         }
 111         iterator = engine_list_head;
 112         while (iterator && !conflict) {
 113                 conflict = (strcmp(iterator->id, e->id) == 0);
 114                 iterator = iterator->next;
 115         }
 116         if (conflict) {
 117                 ENGINEerror(ENGINE_R_CONFLICTING_ENGINE_ID);
 118                 return 0;
 119         }
 120         if (engine_list_head == NULL) {
 121                 /* We are adding to an empty list. */
 122                 if (engine_list_tail) {
 123                         ENGINEerror(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         } else {
 132                 /* We are adding to the tail of an existing list. */
 133                 if ((engine_list_tail == NULL) ||
 134                     (engine_list_tail->next != NULL)) {
 135                         ENGINEerror(ENGINE_R_INTERNAL_LIST_ERROR);
 136                         return 0;
 137                 }
 138                 engine_list_tail->next = e;
 139                 e->prev = engine_list_tail;
 140         }
 141         /* Having the engine in the list assumes a structural
 142          * reference. */
 143         e->struct_ref++;
 144         engine_ref_debug(e, 0, 1)
 145         /* However it came to be, e is the last item in the list. */
 146         engine_list_tail = e;
 147         e->next = NULL;
 148         return 1;
 149 }
 150
 151 static int
 152 engine_list_remove(ENGINE *e)
 153 {
 154         ENGINE *iterator;
 155
 156         if (e == NULL) {
 157                 ENGINEerror(ERR_R_PASSED_NULL_PARAMETER);
 158                 return 0;
 159         }
 160         /* We need to check that e is in our linked list! */
 161         iterator = engine_list_head;
 162         while (iterator && (iterator != e))
 163                 iterator = iterator->next;
 164         if (iterator == NULL) {
 165                 ENGINEerror(ENGINE_R_ENGINE_IS_NOT_IN_LIST);
 166                 return 0;
 167         }
 168         /* un-link e from the chain. */
 169         if (e->next)
 170                 e->next->prev = e->prev;
 171         if (e->prev)
 172                 e->prev->next = e->next;
 173         /* Correct our head/tail if necessary. */
 174         if (engine_list_head == e)
 175                 engine_list_head = e->next;
 176         if (engine_list_tail == e)
 177                 engine_list_tail = e->prev;
 178         engine_free_util(e, 0);
 179         return 1;
 180 }
 181
 182 /* Get the first/last "ENGINE" type available. */
 183 ENGINE *
 184 ENGINE_get_first(void)
 185 {
 186         ENGINE *ret;
 187
 188         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 189         ret = engine_list_head;
 190         if (ret) {
 191                 ret->struct_ref++;
 192                 engine_ref_debug(ret, 0, 1)
 193         }
 194         CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 195         return ret;
 196 }
 197
 198 ENGINE *
 199 ENGINE_get_last(void)
 200 {
 201         ENGINE *ret;
 202
 203         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 204         ret = engine_list_tail;
 205         if (ret) {
 206                 ret->struct_ref++;
 207                 engine_ref_debug(ret, 0, 1)
 208         }
 209         CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 210         return ret;
 211 }
 212
 213 /* Iterate to the next/previous "ENGINE" type (NULL = end of the list). */
 214 ENGINE *
 215 ENGINE_get_next(ENGINE *e)
 216 {
 217         ENGINE *ret = NULL;
 218
 219         if (e == NULL) {
 220                 ENGINEerror(ERR_R_PASSED_NULL_PARAMETER);
 221                 return 0;
 222         }
 223         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 224         ret = e->next;
 225         if (ret) {
 226                 /* Return a valid structural refernce to the next ENGINE */
 227                 ret->struct_ref++;
 228                 engine_ref_debug(ret, 0, 1)
 229         }
 230         CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 231         /* Release the structural reference to the previous ENGINE */
 232         ENGINE_free(e);
 233         return ret;
 234 }
 235
 236 ENGINE *
 237 ENGINE_get_prev(ENGINE *e)
 238 {
 239         ENGINE *ret = NULL;
 240
 241         if (e == NULL) {
 242                 ENGINEerror(ERR_R_PASSED_NULL_PARAMETER);
 243                 return 0;
 244         }
 245         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 246         ret = e->prev;
 247         if (ret) {
 248                 /* Return a valid structural reference to the next ENGINE */
 249                 ret->struct_ref++;
 250                 engine_ref_debug(ret, 0, 1)
 251         }
 252         CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 253         /* Release the structural reference to the previous ENGINE */
 254         ENGINE_free(e);
 255         return ret;
 256 }
 257
 258 /* Add another "ENGINE" type into the list. */
 259 int
 260 ENGINE_add(ENGINE *e)
 261 {
 262         int to_return = 1;
 263
 264         if (e == NULL) {
 265                 ENGINEerror(ERR_R_PASSED_NULL_PARAMETER);
 266                 return 0;
 267         }
 268         if ((e->id == NULL) || (e->name == NULL)) {
 269                 ENGINEerror(ENGINE_R_ID_OR_NAME_MISSING);
 270         }
 271         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 272         if (!engine_list_add(e)) {
 273                 ENGINEerror(ENGINE_R_INTERNAL_LIST_ERROR);
 274                 to_return = 0;
 275         }
 276         CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 277         return to_return;
 278 }
 279
 280 /* Remove an existing "ENGINE" type from the array. */
 281 int
 282 ENGINE_remove(ENGINE *e)
 283 {
 284         int to_return = 1;
 285
 286         if (e == NULL) {
 287                 ENGINEerror(ERR_R_PASSED_NULL_PARAMETER);
 288                 return 0;
 289         }
 290         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 291         if (!engine_list_remove(e)) {
 292                 ENGINEerror(ENGINE_R_INTERNAL_LIST_ERROR);
 293                 to_return = 0;
 294         }
 295         CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 296         return to_return;
 297 }
 298
 299 static void
 300 engine_cpy(ENGINE *dest, const ENGINE *src)
 301 {
 302         dest->id = src->id;
 303         dest->name = src->name;
 304 #ifndef OPENSSL_NO_RSA
 305         dest->rsa_meth = src->rsa_meth;
 306 #endif
 307 #ifndef OPENSSL_NO_DSA
 308         dest->dsa_meth = src->dsa_meth;
 309 #endif
 310 #ifndef OPENSSL_NO_DH
 311         dest->dh_meth = src->dh_meth;
 312 #endif
 313 #ifndef OPENSSL_NO_ECDH
 314         dest->ecdh_meth = src->ecdh_meth;
 315 #endif
 316 #ifndef OPENSSL_NO_ECDSA
 317         dest->ecdsa_meth = src->ecdsa_meth;
 318 #endif
 319         dest->rand_meth = src->rand_meth;
 320         dest->store_meth = src->store_meth;
 321         dest->ciphers = src->ciphers;
 322         dest->digests = src->digests;
 323         dest->pkey_meths = src->pkey_meths;
 324         dest->destroy = src->destroy;
 325         dest->init = src->init;
 326         dest->finish = src->finish;
 327         dest->ctrl = src->ctrl;
 328         dest->load_privkey = src->load_privkey;
 329         dest->load_pubkey = src->load_pubkey;
 330         dest->cmd_defns = src->cmd_defns;
 331         dest->flags = src->flags;
 332 }
 333
 334 ENGINE *
 335 ENGINE_by_id(const char *id)
 336 {
 337         ENGINE *iterator;
 338
 339         if (id == NULL) {
 340                 ENGINEerror(ERR_R_PASSED_NULL_PARAMETER);
 341                 return NULL;
 342         }
 343         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 344         iterator = engine_list_head;
 345         while (iterator && (strcmp(id, iterator->id) != 0))
 346                 iterator = iterator->next;
 347         if (iterator) {
 348                 /* We need to return a structural reference. If this is an
 349                  * ENGINE type that returns copies, make a duplicate - otherwise
 350                  * increment the existing ENGINE's reference count. */
 351                 if (iterator->flags & ENGINE_FLAGS_BY_ID_COPY) {
 352                         ENGINE *cp = ENGINE_new();
 353                         if (!cp)
 354                                 iterator = NULL;
 355                         else {
 356                                 engine_cpy(cp, iterator);
 357                                 iterator = cp;
 358                         }
 359                 } else {
 360                         iterator->struct_ref++;
 361                         engine_ref_debug(iterator, 0, 1)
 362                 }
 363         }
 364         CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 365
 366         if (iterator == NULL) {
 367                 ENGINEerror(ENGINE_R_NO_SUCH_ENGINE);
 368                 ERR_asprintf_error_data("id=%s", id);
 369         }
 370         return iterator;
 371 }
 372
 373 int
 374 ENGINE_up_ref(ENGINE *e)
 375 {
 376         if (e == NULL) {
 377                 ENGINEerror(ERR_R_PASSED_NULL_PARAMETER);
 378                 return 0;
 379         }
 380         CRYPTO_add(&e->struct_ref, 1, CRYPTO_LOCK_ENGINE);
 381         return 1;
 382 }