crypto/engine/eng_list.c

   1 /*
   2  * Written by Geoff Thorpe (geoff@geoffthorpe.net) for the OpenSSL project
   3  * 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 "eng_int.h"
  65
  66 /*
  67  * The linked-list of pointers to engine types. engine_list_head incorporates
  68  * an implicit structural reference but engine_list_tail does not - the
  69  * latter is a computational niceity and only points to something that is
  70  * already pointed to by its predecessor in the list (or engine_list_head
  71  * itself). In the same way, the use of the "prev" pointer in each ENGINE is
  72  * to save excessive list iteration, it doesn't correspond to an extra
  73  * structural reference. Hence, engine_list_head, and each non-null "next"
  74  * pointer account for the list itself assuming exactly 1 structural
  75  * reference on each list member.
  76  */
  77 static ENGINE *engine_list_head = NULL;
  78 static ENGINE *engine_list_tail = NULL;
  79
  80 /*
  81  * This cleanup function is only needed internally. If it should be called,
  82  * we register it with the "ENGINE_cleanup()" stack to be called during
  83  * cleanup.
  84  */
  85
  86 static void engine_list_cleanup(void)
  87 {
  88     ENGINE *iterator = engine_list_head;
  89
  90     while (iterator != NULL) {
  91         ENGINE_remove(iterator);
  92         iterator = engine_list_head;
  93     }
  94     return;
  95 }
  96
  97 /*
  98  * These static functions starting with a lower case "engine_" always take
  99  * place when CRYPTO_LOCK_ENGINE has been locked up.
 100  */
 101 static int engine_list_add(ENGINE *e)
 102 {
 103     int conflict = 0;
 104     ENGINE *iterator = NULL;
 105
 106     if (e == NULL) {
 107         ENGINEerr(ENGINE_F_ENGINE_LIST_ADD, ERR_R_PASSED_NULL_PARAMETER);
 108         return 0;
 109     }
 110     iterator = engine_list_head;
 111     while (iterator && !conflict) {
 112         conflict = (strcmp(iterator->id, e->id) == 0);
 113         iterator = iterator->next;
 114     }
 115     if (conflict) {
 116         ENGINEerr(ENGINE_F_ENGINE_LIST_ADD, ENGINE_R_CONFLICTING_ENGINE_ID);
 117         return 0;
 118     }
 119     if (engine_list_head == NULL) {
 120         /* We are adding to an empty list. */
 121         if (engine_list_tail) {
 122             ENGINEerr(ENGINE_F_ENGINE_LIST_ADD, ENGINE_R_INTERNAL_LIST_ERROR);
 123             return 0;
 124         }
 125         engine_list_head = e;
 126         e->prev = NULL;
 127         /*
 128          * The first time the list allocates, we should register the cleanup.
 129          */
 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) || (engine_list_tail->next != NULL)) {
 134             ENGINEerr(ENGINE_F_ENGINE_LIST_ADD, ENGINE_R_INTERNAL_LIST_ERROR);
 135             return 0;
 136         }
 137         engine_list_tail->next = e;
 138         e->prev = engine_list_tail;
 139     }
 140     /*
 141      * Having the engine in the list assumes a structural reference.
 142      */
 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 engine_list_remove(ENGINE *e)
 152 {
 153     ENGINE *iterator;
 154
 155     if (e == NULL) {
 156         ENGINEerr(ENGINE_F_ENGINE_LIST_REMOVE, ERR_R_PASSED_NULL_PARAMETER);
 157         return 0;
 158     }
 159     /* We need to check that e is in our linked list! */
 160     iterator = engine_list_head;
 161     while (iterator && (iterator != e))
 162         iterator = iterator->next;
 163     if (iterator == NULL) {
 164         ENGINEerr(ENGINE_F_ENGINE_LIST_REMOVE,
 165                   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 *ENGINE_get_first(void)
 184 {
 185     ENGINE *ret;
 186
 187     CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 188     ret = engine_list_head;
 189     if (ret) {
 190         ret->struct_ref++;
 191         engine_ref_debug(ret, 0, 1)
 192     }
 193     CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 194     return ret;
 195 }
 196
 197 ENGINE *ENGINE_get_last(void)
 198 {
 199     ENGINE *ret;
 200
 201     CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 202     ret = engine_list_tail;
 203     if (ret) {
 204         ret->struct_ref++;
 205         engine_ref_debug(ret, 0, 1)
 206     }
 207     CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 208     return ret;
 209 }
 210
 211 /* Iterate to the next/previous "ENGINE" type (NULL = end of the list). */
 212 ENGINE *ENGINE_get_next(ENGINE *e)
 213 {
 214     ENGINE *ret = NULL;
 215     if (e == NULL) {
 216         ENGINEerr(ENGINE_F_ENGINE_GET_NEXT, ERR_R_PASSED_NULL_PARAMETER);
 217         return 0;
 218     }
 219     CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 220     ret = e->next;
 221     if (ret) {
 222         /* Return a valid structural refernce to the next ENGINE */
 223         ret->struct_ref++;
 224         engine_ref_debug(ret, 0, 1)
 225     }
 226     CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 227     /* Release the structural reference to the previous ENGINE */
 228     ENGINE_free(e);
 229     return ret;
 230 }
 231
 232 ENGINE *ENGINE_get_prev(ENGINE *e)
 233 {
 234     ENGINE *ret = NULL;
 235     if (e == NULL) {
 236         ENGINEerr(ENGINE_F_ENGINE_GET_PREV, ERR_R_PASSED_NULL_PARAMETER);
 237         return 0;
 238     }
 239     CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 240     ret = e->prev;
 241     if (ret) {
 242         /* Return a valid structural reference to the next ENGINE */
 243         ret->struct_ref++;
 244         engine_ref_debug(ret, 0, 1)
 245     }
 246     CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 247     /* Release the structural reference to the previous ENGINE */
 248     ENGINE_free(e);
 249     return ret;
 250 }
 251
 252 /* Add another "ENGINE" type into the list. */
 253 int ENGINE_add(ENGINE *e)
 254 {
 255     int to_return = 1;
 256     if (e == NULL) {
 257         ENGINEerr(ENGINE_F_ENGINE_ADD, ERR_R_PASSED_NULL_PARAMETER);
 258         return 0;
 259     }
 260     if ((e->id == NULL) || (e->name == NULL)) {
 261         ENGINEerr(ENGINE_F_ENGINE_ADD, ENGINE_R_ID_OR_NAME_MISSING);
 262         return 0;
 263     }
 264     CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 265     if (!engine_list_add(e)) {
 266         ENGINEerr(ENGINE_F_ENGINE_ADD, ENGINE_R_INTERNAL_LIST_ERROR);
 267         to_return = 0;
 268     }
 269     CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 270     return to_return;
 271 }
 272
 273 /* Remove an existing "ENGINE" type from the array. */
 274 int ENGINE_remove(ENGINE *e)
 275 {
 276     int to_return = 1;
 277     if (e == NULL) {
 278         ENGINEerr(ENGINE_F_ENGINE_REMOVE, ERR_R_PASSED_NULL_PARAMETER);
 279         return 0;
 280     }
 281     CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 282     if (!engine_list_remove(e)) {
 283         ENGINEerr(ENGINE_F_ENGINE_REMOVE, ENGINE_R_INTERNAL_LIST_ERROR);
 284         to_return = 0;
 285     }
 286     CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 287     return to_return;
 288 }
 289
 290 static void engine_cpy(ENGINE *dest, const ENGINE *src)
 291 {
 292     dest->id = src->id;
 293     dest->name = src->name;
 294 #ifndef OPENSSL_NO_RSA
 295     dest->rsa_meth = src->rsa_meth;
 296 #endif
 297 #ifndef OPENSSL_NO_DSA
 298     dest->dsa_meth = src->dsa_meth;
 299 #endif
 300 #ifndef OPENSSL_NO_DH
 301     dest->dh_meth = src->dh_meth;
 302 #endif
 303 #ifndef OPENSSL_NO_EC
 304     dest->ec_meth = src->ec_meth;
 305 #endif
 306     dest->rand_meth = src->rand_meth;
 307     dest->store_meth = src->store_meth;
 308     dest->ciphers = src->ciphers;
 309     dest->digests = src->digests;
 310     dest->pkey_meths = src->pkey_meths;
 311     dest->destroy = src->destroy;
 312     dest->init = src->init;
 313     dest->finish = src->finish;
 314     dest->ctrl = src->ctrl;
 315     dest->load_privkey = src->load_privkey;
 316     dest->load_pubkey = src->load_pubkey;
 317     dest->cmd_defns = src->cmd_defns;
 318     dest->flags = src->flags;
 319 }
 320
 321 ENGINE *ENGINE_by_id(const char *id)
 322 {
 323     ENGINE *iterator;
 324     char *load_dir = NULL;
 325     if (id == NULL) {
 326         ENGINEerr(ENGINE_F_ENGINE_BY_ID, ERR_R_PASSED_NULL_PARAMETER);
 327         return NULL;
 328     }
 329     CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 330     iterator = engine_list_head;
 331     while (iterator && (strcmp(id, iterator->id) != 0))
 332         iterator = iterator->next;
 333     if (iterator != NULL) {
 334         /*
 335          * We need to return a structural reference. If this is an ENGINE
 336          * type that returns copies, make a duplicate - otherwise increment
 337          * the existing ENGINE's reference count.
 338          */
 339         if (iterator->flags & ENGINE_FLAGS_BY_ID_COPY) {
 340             ENGINE *cp = ENGINE_new();
 341             if (cp == NULL)
 342                 iterator = NULL;
 343             else {
 344                 engine_cpy(cp, iterator);
 345                 iterator = cp;
 346             }
 347         } else {
 348             iterator->struct_ref++;
 349             engine_ref_debug(iterator, 0, 1)
 350         }
 351     }
 352     CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 353     if (iterator != NULL)
 354         return iterator;
 355     /*
 356      * Prevent infinite recusrion if we're looking for the dynamic engine.
 357      */
 358     if (strcmp(id, "dynamic")) {
 359 # ifdef OPENSSL_SYS_VMS
 360         if ((load_dir = getenv("OPENSSL_ENGINES")) == 0)
 361             load_dir = "SSLROOT:[ENGINES]";
 362 # else
 363         if ((load_dir = getenv("OPENSSL_ENGINES")) == 0)
 364             load_dir = ENGINESDIR;
 365 # endif
 366         iterator = ENGINE_by_id("dynamic");
 367         if (!iterator || !ENGINE_ctrl_cmd_string(iterator, "ID", id, 0) ||
 368             !ENGINE_ctrl_cmd_string(iterator, "DIR_LOAD", "2", 0) ||
 369             !ENGINE_ctrl_cmd_string(iterator, "DIR_ADD",
 370                                     load_dir, 0) ||
 371             !ENGINE_ctrl_cmd_string(iterator, "LIST_ADD", "1", 0) ||
 372             !ENGINE_ctrl_cmd_string(iterator, "LOAD", NULL, 0))
 373             goto notfound;
 374         return iterator;
 375     }
 376  notfound:
 377     ENGINE_free(iterator);
 378     ENGINEerr(ENGINE_F_ENGINE_BY_ID, ENGINE_R_NO_SUCH_ENGINE);
 379     ERR_add_error_data(2, "id=", id);
 380     return NULL;
 381     /* EEK! Experimental code ends */
 382 }
 383
 384 int ENGINE_up_ref(ENGINE *e)
 385 {
 386     if (e == NULL) {
 387         ENGINEerr(ENGINE_F_ENGINE_UP_REF, ERR_R_PASSED_NULL_PARAMETER);
 388         return 0;
 389     }
 390     CRYPTO_add(&e->struct_ref, 1, CRYPTO_LOCK_ENGINE);
 391     return 1;
 392 }