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 IMPLEMENT_LHASH_HASH_FN(engine_pile, ENGINE_PILE)
 110 static IMPLEMENT_LHASH_COMP_FN(engine_pile, ENGINE_PILE)
 111
 112 static int int_table_check(ENGINE_TABLE **t, int create)
 113 {
 114     LHASH_OF(ENGINE_PILE) *lh;
 115
 116     if (*t)
 117         return 1;
 118     if (!create)
 119         return 0;
 120     if ((lh = lh_ENGINE_PILE_new()) == NULL)
 121         return 0;
 122     *t = (ENGINE_TABLE *)lh;
 123     return 1;
 124 }
 125
 126 /*
 127  * Privately exposed (via eng_int.h) functions for adding and/or removing
 128  * ENGINEs from the implementation table
 129  */
 130 int engine_table_register(ENGINE_TABLE **table, ENGINE_CLEANUP_CB *cleanup,
 131                           ENGINE *e, const int *nids, int num_nids,
 132                           int setdefault)
 133 {
 134     int ret = 0, added = 0;
 135     ENGINE_PILE tmplate, *fnd;
 136     CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 137     if (!(*table))
 138         added = 1;
 139     if (!int_table_check(table, 1))
 140         goto end;
 141     if (added)
 142         /* The cleanup callback needs to be added */
 143         engine_cleanup_add_first(cleanup);
 144     while (num_nids--) {
 145         tmplate.nid = *nids;
 146         fnd = lh_ENGINE_PILE_retrieve(&(*table)->piles, &tmplate);
 147         if (!fnd) {
 148             fnd = OPENSSL_malloc(sizeof(*fnd));
 149             if (fnd == NULL)
 150                 goto end;
 151             fnd->uptodate = 1;
 152             fnd->nid = *nids;
 153             fnd->sk = sk_ENGINE_new_null();
 154             if (!fnd->sk) {
 155                 OPENSSL_free(fnd);
 156                 goto end;
 157             }
 158             fnd->funct = NULL;
 159             (void)lh_ENGINE_PILE_insert(&(*table)->piles, fnd);
 160         }
 161         /* A registration shouldn't add duplciate entries */
 162         (void)sk_ENGINE_delete_ptr(fnd->sk, e);
 163         /*
 164          * if 'setdefault', this ENGINE goes to the head of the list
 165          */
 166         if (!sk_ENGINE_push(fnd->sk, e))
 167             goto end;
 168         /* "touch" this ENGINE_PILE */
 169         fnd->uptodate = 0;
 170         if (setdefault) {
 171             if (!engine_unlocked_init(e)) {
 172                 ENGINEerr(ENGINE_F_ENGINE_TABLE_REGISTER,
 173                           ENGINE_R_INIT_FAILED);
 174                 goto end;
 175             }
 176             if (fnd->funct)
 177                 engine_unlocked_finish(fnd->funct, 0);
 178             fnd->funct = e;
 179             fnd->uptodate = 1;
 180         }
 181         nids++;
 182     }
 183     ret = 1;
 184  end:
 185     CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 186     return ret;
 187 }
 188
 189 static void int_unregister_cb_doall_arg(ENGINE_PILE *pile, ENGINE *e)
 190 {
 191     int n;
 192     /* Iterate the 'c->sk' stack removing any occurrence of 'e' */
 193     while ((n = sk_ENGINE_find(pile->sk, e)) >= 0) {
 194         (void)sk_ENGINE_delete(pile->sk, n);
 195         pile->uptodate = 0;
 196     }
 197     if (pile->funct == e) {
 198         engine_unlocked_finish(e, 0);
 199         pile->funct = NULL;
 200     }
 201 }
 202
 203 static IMPLEMENT_LHASH_DOALL_ARG_FN(int_unregister_cb, ENGINE_PILE, ENGINE)
 204
 205 void engine_table_unregister(ENGINE_TABLE **table, ENGINE *e)
 206 {
 207     CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 208     if (int_table_check(table, 0))
 209         lh_ENGINE_PILE_doall_arg(&(*table)->piles,
 210                                  LHASH_DOALL_ARG_FN(int_unregister_cb),
 211                                  ENGINE, e);
 212     CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 213 }
 214
 215 static void int_cleanup_cb_doall(ENGINE_PILE *p)
 216 {
 217     if (!p)
 218         return;
 219     sk_ENGINE_free(p->sk);
 220     if (p->funct)
 221         engine_unlocked_finish(p->funct, 0);
 222     OPENSSL_free(p);
 223 }
 224
 225 static IMPLEMENT_LHASH_DOALL_FN(int_cleanup_cb, ENGINE_PILE)
 226
 227 void engine_table_cleanup(ENGINE_TABLE **table)
 228 {
 229     CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 230     if (*table) {
 231         lh_ENGINE_PILE_doall(&(*table)->piles,
 232                              LHASH_DOALL_FN(int_cleanup_cb));
 233         lh_ENGINE_PILE_free(&(*table)->piles);
 234         *table = NULL;
 235     }
 236     CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 237 }
 238
 239 /* return a functional reference for a given 'nid' */
 240 #ifndef ENGINE_TABLE_DEBUG
 241 ENGINE *engine_table_select(ENGINE_TABLE **table, int nid)
 242 #else
 243 ENGINE *engine_table_select_tmp(ENGINE_TABLE **table, int nid, const char *f,
 244                                 int l)
 245 #endif
 246 {
 247     ENGINE *ret = NULL;
 248     ENGINE_PILE tmplate, *fnd = NULL;
 249     int initres, loop = 0;
 250
 251     if (!(*table)) {
 252 #ifdef ENGINE_TABLE_DEBUG
 253         fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, nothing "
 254                 "registered!\n", f, l, nid);
 255 #endif
 256         return NULL;
 257     }
 258     ERR_set_mark();
 259     CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 260     /*
 261      * Check again inside the lock otherwise we could race against cleanup
 262      * operations. But don't worry about a fprintf(stderr).
 263      */
 264     if (!int_table_check(table, 0))
 265         goto end;
 266     tmplate.nid = nid;
 267     fnd = lh_ENGINE_PILE_retrieve(&(*table)->piles, &tmplate);
 268     if (!fnd)
 269         goto end;
 270     if (fnd->funct && engine_unlocked_init(fnd->funct)) {
 271 #ifdef ENGINE_TABLE_DEBUG
 272         fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, using "
 273                 "ENGINE '%s' cached\n", f, l, nid, fnd->funct->id);
 274 #endif
 275         ret = fnd->funct;
 276         goto end;
 277     }
 278     if (fnd->uptodate) {
 279         ret = fnd->funct;
 280         goto end;
 281     }
 282  trynext:
 283     ret = sk_ENGINE_value(fnd->sk, loop++);
 284     if (!ret) {
 285 #ifdef ENGINE_TABLE_DEBUG
 286         fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, no "
 287                 "registered implementations would initialise\n", f, l, nid);
 288 #endif
 289         goto end;
 290     }
 291     /* Try to initialise the ENGINE? */
 292     if ((ret->funct_ref > 0) || !(table_flags & ENGINE_TABLE_FLAG_NOINIT))
 293         initres = engine_unlocked_init(ret);
 294     else
 295         initres = 0;
 296     if (initres) {
 297         /* Update 'funct' */
 298         if ((fnd->funct != ret) && engine_unlocked_init(ret)) {
 299             /* If there was a previous default we release it. */
 300             if (fnd->funct)
 301                 engine_unlocked_finish(fnd->funct, 0);
 302             fnd->funct = ret;
 303 #ifdef ENGINE_TABLE_DEBUG
 304             fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, "
 305                     "setting default to '%s'\n", f, l, nid, ret->id);
 306 #endif
 307         }
 308 #ifdef ENGINE_TABLE_DEBUG
 309         fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, using "
 310                 "newly initialised '%s'\n", f, l, nid, ret->id);
 311 #endif
 312         goto end;
 313     }
 314     goto trynext;
 315  end:
 316     /*
 317      * If it failed, it is unlikely to succeed again until some future
 318      * registrations have taken place. In all cases, we cache.
 319      */
 320     if (fnd)
 321         fnd->uptodate = 1;
 322 #ifdef ENGINE_TABLE_DEBUG
 323     if (ret)
 324         fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, caching "
 325                 "ENGINE '%s'\n", f, l, nid, ret->id);
 326     else
 327         fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, caching "
 328                 "'no matching ENGINE'\n", f, l, nid);
 329 #endif
 330     CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 331     /*
 332      * Whatever happened, any failed init()s are not failures in this
 333      * context, so clear our error state.
 334      */
 335     ERR_pop_to_mark();
 336     return ret;
 337 }
 338
 339 /* Table enumeration */
 340
 341 static void int_cb_doall_arg(ENGINE_PILE *pile, ENGINE_PILE_DOALL *dall)
 342 {
 343     dall->cb(pile->nid, pile->sk, pile->funct, dall->arg);
 344 }
 345
 346 static IMPLEMENT_LHASH_DOALL_ARG_FN(int_cb, ENGINE_PILE, ENGINE_PILE_DOALL)
 347
 348 void engine_table_doall(ENGINE_TABLE *table, engine_table_doall_cb *cb,
 349                         void *arg)
 350 {
 351     ENGINE_PILE_DOALL dall;
 352     dall.cb = cb;
 353     dall.arg = arg;
 354     if (table)
 355         lh_ENGINE_PILE_doall_arg(&table->piles,
 356                                  LHASH_DOALL_ARG_FN(int_cb),
 357                                  ENGINE_PILE_DOALL, &dall);
 358 }