crypto/engine/eng_table.c

   1 /* ====================================================================
   2  * Copyright (c) 2001 The OpenSSL Project.  All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  *
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  *
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in
  13  *    the documentation and/or other materials provided with the
  14  *    distribution.
  15  *
  16  * 3. All advertising materials mentioning features or use of this
  17  *    software must display the following acknowledgment:
  18  *    "This product includes software developed by the OpenSSL Project
  19  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
  20  *
  21  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  22  *    endorse or promote products derived from this software without
  23  *    prior written permission. For written permission, please contact
  24  *    licensing@OpenSSL.org.
  25  *
  26  * 5. Products derived from this software may not be called "OpenSSL"
  27  *    nor may "OpenSSL" appear in their names without prior written
  28  *    permission of the OpenSSL Project.
  29  *
  30  * 6. Redistributions of any form whatsoever must retain the following
  31  *    acknowledgment:
  32  *    "This product includes software developed by the OpenSSL Project
  33  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
  34  *
  35  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  36  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  37  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  38  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
  39  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  40  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  41  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  42  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  43  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  44  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  45  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  46  * OF THE POSSIBILITY OF SUCH DAMAGE.
  47  * ====================================================================
  48  *
  49  * This product includes cryptographic software written by Eric Young
  50  * (eay@cryptsoft.com).  This product includes software written by Tim
  51  * Hudson (tjh@cryptsoft.com).
  52  *
  53  */
  54
  55 #include "internal/cryptlib.h"
  56 #include <openssl/evp.h>
  57 #include <openssl/lhash.h>
  58 #include "eng_int.h"
  59
  60 /* The type of the items in the table */
  61 struct st_engine_pile {
  62     /* The 'nid' of this algorithm/mode */
  63     int nid;
  64     /* ENGINEs that implement this algorithm/mode. */
  65     STACK_OF(ENGINE) *sk;
  66     /* The default ENGINE to perform this algorithm/mode. */
  67     ENGINE *funct;
  68     /*
  69      * Zero if 'sk' is newer than the cached 'funct', non-zero otherwise
  70      */
  71     int uptodate;
  72 };
  73
  74 /* The type exposed in eng_int.h */
  75 struct st_engine_table {
  76     LHASH_OF(ENGINE_PILE) piles;
  77 };                              /* ENGINE_TABLE */
  78
  79 typedef struct st_engine_pile_doall {
  80     engine_table_doall_cb *cb;
  81     void *arg;
  82 } ENGINE_PILE_DOALL;
  83
  84 /* Global flags (ENGINE_TABLE_FLAG_***). */
  85 static unsigned int table_flags = 0;
  86
  87 /* API function manipulating 'table_flags' */
  88 unsigned int ENGINE_get_table_flags(void)
  89 {
  90     return table_flags;
  91 }
  92
  93 void ENGINE_set_table_flags(unsigned int flags)
  94 {
  95     table_flags = flags;
  96 }
  97
  98 /* Internal functions for the "piles" hash table */
  99 static unsigned long engine_pile_hash(const ENGINE_PILE *c)
 100 {
 101     return c->nid;
 102 }
 103
 104 static int engine_pile_cmp(const ENGINE_PILE *a, const ENGINE_PILE *b)
 105 {
 106     return a->nid - b->nid;
 107 }
 108
 109 static int int_table_check(ENGINE_TABLE **t, int create)
 110 {
 111     LHASH_OF(ENGINE_PILE) *lh;
 112
 113     if (*t)
 114         return 1;
 115     if (!create)
 116         return 0;
 117     if ((lh = lh_ENGINE_PILE_new(engine_pile_hash, engine_pile_cmp)) == NULL)
 118         return 0;
 119     *t = (ENGINE_TABLE *)lh;
 120     return 1;
 121 }
 122
 123 /*
 124  * Privately exposed (via eng_int.h) functions for adding and/or removing
 125  * ENGINEs from the implementation table
 126  */
 127 int engine_table_register(ENGINE_TABLE **table, ENGINE_CLEANUP_CB *cleanup,
 128                           ENGINE *e, const int *nids, int num_nids,
 129                           int setdefault)
 130 {
 131     int ret = 0, added = 0;
 132     ENGINE_PILE tmplate, *fnd;
 133     CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 134     if (!(*table))
 135         added = 1;
 136     if (!int_table_check(table, 1))
 137         goto end;
 138     if (added)
 139         /* The cleanup callback needs to be added */
 140         engine_cleanup_add_first(cleanup);
 141     while (num_nids--) {
 142         tmplate.nid = *nids;
 143         fnd = lh_ENGINE_PILE_retrieve(&(*table)->piles, &tmplate);
 144         if (!fnd) {
 145             fnd = OPENSSL_malloc(sizeof(*fnd));
 146             if (fnd == NULL)
 147                 goto end;
 148             fnd->uptodate = 1;
 149             fnd->nid = *nids;
 150             fnd->sk = sk_ENGINE_new_null();
 151             if (!fnd->sk) {
 152                 OPENSSL_free(fnd);
 153                 goto end;
 154             }
 155             fnd->funct = NULL;
 156             (void)lh_ENGINE_PILE_insert(&(*table)->piles, fnd);
 157         }
 158         /* A registration shouldn't add duplicate entries */
 159         (void)sk_ENGINE_delete_ptr(fnd->sk, e);
 160         /*
 161          * if 'setdefault', this ENGINE goes to the head of the list
 162          */
 163         if (!sk_ENGINE_push(fnd->sk, e))
 164             goto end;
 165         /* "touch" this ENGINE_PILE */
 166         fnd->uptodate = 0;
 167         if (setdefault) {
 168             if (!engine_unlocked_init(e)) {
 169                 ENGINEerr(ENGINE_F_ENGINE_TABLE_REGISTER,
 170                           ENGINE_R_INIT_FAILED);
 171                 goto end;
 172             }
 173             if (fnd->funct)
 174                 engine_unlocked_finish(fnd->funct, 0);
 175             fnd->funct = e;
 176             fnd->uptodate = 1;
 177         }
 178         nids++;
 179     }
 180     ret = 1;
 181  end:
 182     CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 183     return ret;
 184 }
 185
 186 static void int_unregister_cb(ENGINE_PILE *pile, ENGINE *e)
 187 {
 188     int n;
 189     /* Iterate the 'c->sk' stack removing any occurrence of 'e' */
 190     while ((n = sk_ENGINE_find(pile->sk, e)) >= 0) {
 191         (void)sk_ENGINE_delete(pile->sk, n);
 192         pile->uptodate = 0;
 193     }
 194     if (pile->funct == e) {
 195         engine_unlocked_finish(e, 0);
 196         pile->funct = NULL;
 197     }
 198 }
 199
 200 IMPLEMENT_LHASH_DOALL_ARG(ENGINE_PILE, ENGINE);
 201
 202 void engine_table_unregister(ENGINE_TABLE **table, ENGINE *e)
 203 {
 204     CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 205     if (int_table_check(table, 0))
 206         lh_ENGINE_PILE_doall_ENGINE(&(*table)->piles, int_unregister_cb, e);
 207     CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 208 }
 209
 210 static void int_cleanup_cb_doall(ENGINE_PILE *p)
 211 {
 212     if (!p)
 213         return;
 214     sk_ENGINE_free(p->sk);
 215     if (p->funct)
 216         engine_unlocked_finish(p->funct, 0);
 217     OPENSSL_free(p);
 218 }
 219
 220 void engine_table_cleanup(ENGINE_TABLE **table)
 221 {
 222     CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 223     if (*table) {
 224         lh_ENGINE_PILE_doall(&(*table)->piles, int_cleanup_cb_doall);
 225         lh_ENGINE_PILE_free(&(*table)->piles);
 226         *table = NULL;
 227     }
 228     CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 229 }
 230
 231 /* return a functional reference for a given 'nid' */
 232 #ifndef ENGINE_TABLE_DEBUG
 233 ENGINE *engine_table_select(ENGINE_TABLE **table, int nid)
 234 #else
 235 ENGINE *engine_table_select_tmp(ENGINE_TABLE **table, int nid, const char *f,
 236                                 int l)
 237 #endif
 238 {
 239     ENGINE *ret = NULL;
 240     ENGINE_PILE tmplate, *fnd = NULL;
 241     int initres, loop = 0;
 242
 243     if (!(*table)) {
 244 #ifdef ENGINE_TABLE_DEBUG
 245         fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, nothing "
 246                 "registered!\n", f, l, nid);
 247 #endif
 248         return NULL;
 249     }
 250     ERR_set_mark();
 251     CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 252     /*
 253      * Check again inside the lock otherwise we could race against cleanup
 254      * operations. But don't worry about a fprintf(stderr).
 255      */
 256     if (!int_table_check(table, 0))
 257         goto end;
 258     tmplate.nid = nid;
 259     fnd = lh_ENGINE_PILE_retrieve(&(*table)->piles, &tmplate);
 260     if (!fnd)
 261         goto end;
 262     if (fnd->funct && engine_unlocked_init(fnd->funct)) {
 263 #ifdef ENGINE_TABLE_DEBUG
 264         fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, using "
 265                 "ENGINE '%s' cached\n", f, l, nid, fnd->funct->id);
 266 #endif
 267         ret = fnd->funct;
 268         goto end;
 269     }
 270     if (fnd->uptodate) {
 271         ret = fnd->funct;
 272         goto end;
 273     }
 274  trynext:
 275     ret = sk_ENGINE_value(fnd->sk, loop++);
 276     if (!ret) {
 277 #ifdef ENGINE_TABLE_DEBUG
 278         fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, no "
 279                 "registered implementations would initialise\n", f, l, nid);
 280 #endif
 281         goto end;
 282     }
 283     /* Try to initialise the ENGINE? */
 284     if ((ret->funct_ref > 0) || !(table_flags & ENGINE_TABLE_FLAG_NOINIT))
 285         initres = engine_unlocked_init(ret);
 286     else
 287         initres = 0;
 288     if (initres) {
 289         /* Update 'funct' */
 290         if ((fnd->funct != ret) && engine_unlocked_init(ret)) {
 291             /* If there was a previous default we release it. */
 292             if (fnd->funct)
 293                 engine_unlocked_finish(fnd->funct, 0);
 294             fnd->funct = ret;
 295 #ifdef ENGINE_TABLE_DEBUG
 296             fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, "
 297                     "setting default to '%s'\n", f, l, nid, ret->id);
 298 #endif
 299         }
 300 #ifdef ENGINE_TABLE_DEBUG
 301         fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, using "
 302                 "newly initialised '%s'\n", f, l, nid, ret->id);
 303 #endif
 304         goto end;
 305     }
 306     goto trynext;
 307  end:
 308     /*
 309      * If it failed, it is unlikely to succeed again until some future
 310      * registrations have taken place. In all cases, we cache.
 311      */
 312     if (fnd)
 313         fnd->uptodate = 1;
 314 #ifdef ENGINE_TABLE_DEBUG
 315     if (ret)
 316         fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, caching "
 317                 "ENGINE '%s'\n", f, l, nid, ret->id);
 318     else
 319         fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, caching "
 320                 "'no matching ENGINE'\n", f, l, nid);
 321 #endif
 322     CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 323     /*
 324      * Whatever happened, any failed init()s are not failures in this
 325      * context, so clear our error state.
 326      */
 327     ERR_pop_to_mark();
 328     return ret;
 329 }
 330
 331 /* Table enumeration */
 332
 333 static void int_dall(const ENGINE_PILE *pile, ENGINE_PILE_DOALL *dall)
 334 {
 335     dall->cb(pile->nid, pile->sk, pile->funct, dall->arg);
 336 }
 337
 338 IMPLEMENT_LHASH_DOALL_ARG_CONST(ENGINE_PILE, ENGINE_PILE_DOALL);
 339
 340 void engine_table_doall(ENGINE_TABLE *table, engine_table_doall_cb *cb,
 341                         void *arg)
 342 {
 343     ENGINE_PILE_DOALL dall;
 344     dall.cb = cb;
 345     dall.arg = arg;
 346     if (table)
 347         lh_ENGINE_PILE_doall_ENGINE_PILE_DOALL(&table->piles, int_dall, &dall);
 348 }