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 typedef 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 } ENGINE_PILE;
  73
  74 DECLARE_LHASH_OF(ENGINE_PILE);
  75
  76 /* The type exposed in eng_int.h */
  77 struct st_engine_table {
  78     LHASH_OF(ENGINE_PILE) piles;
  79 };                              /* ENGINE_TABLE */
  80
  81 typedef struct st_engine_pile_doall {
  82     engine_table_doall_cb *cb;
  83     void *arg;
  84 } ENGINE_PILE_DOALL;
  85
  86 /* Global flags (ENGINE_TABLE_FLAG_***). */
  87 static unsigned int table_flags = 0;
  88
  89 /* API function manipulating 'table_flags' */
  90 unsigned int ENGINE_get_table_flags(void)
  91 {
  92     return table_flags;
  93 }
  94
  95 void ENGINE_set_table_flags(unsigned int flags)
  96 {
  97     table_flags = flags;
  98 }
  99
 100 /* Internal functions for the "piles" hash table */
 101 static unsigned long engine_pile_hash(const ENGINE_PILE *c)
 102 {
 103     return c->nid;
 104 }
 105
 106 static int engine_pile_cmp(const ENGINE_PILE *a, const ENGINE_PILE *b)
 107 {
 108     return a->nid - b->nid;
 109 }
 110
 111 static IMPLEMENT_LHASH_HASH_FN(engine_pile, ENGINE_PILE)
 112 static IMPLEMENT_LHASH_COMP_FN(engine_pile, ENGINE_PILE)
 113
 114 static int int_table_check(ENGINE_TABLE **t, int create)
 115 {
 116     LHASH_OF(ENGINE_PILE) *lh;
 117
 118     if (*t)
 119         return 1;
 120     if (!create)
 121         return 0;
 122     if ((lh = lh_ENGINE_PILE_new()) == NULL)
 123         return 0;
 124     *t = (ENGINE_TABLE *)lh;
 125     return 1;
 126 }
 127
 128 /*
 129  * Privately exposed (via eng_int.h) functions for adding and/or removing
 130  * ENGINEs from the implementation table
 131  */
 132 int engine_table_register(ENGINE_TABLE **table, ENGINE_CLEANUP_CB *cleanup,
 133                           ENGINE *e, const int *nids, int num_nids,
 134                           int setdefault)
 135 {
 136     int ret = 0, added = 0;
 137     ENGINE_PILE tmplate, *fnd;
 138     CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 139     if (!(*table))
 140         added = 1;
 141     if (!int_table_check(table, 1))
 142         goto end;
 143     if (added)
 144         /* The cleanup callback needs to be added */
 145         engine_cleanup_add_first(cleanup);
 146     while (num_nids--) {
 147         tmplate.nid = *nids;
 148         fnd = lh_ENGINE_PILE_retrieve(&(*table)->piles, &tmplate);
 149         if (!fnd) {
 150             fnd = OPENSSL_malloc(sizeof(*fnd));
 151             if (fnd == NULL)
 152                 goto end;
 153             fnd->uptodate = 1;
 154             fnd->nid = *nids;
 155             fnd->sk = sk_ENGINE_new_null();
 156             if (!fnd->sk) {
 157                 OPENSSL_free(fnd);
 158                 goto end;
 159             }
 160             fnd->funct = NULL;
 161             (void)lh_ENGINE_PILE_insert(&(*table)->piles, fnd);
 162         }
 163         /* A registration shouldn't add duplciate entries */
 164         (void)sk_ENGINE_delete_ptr(fnd->sk, e);
 165         /*
 166          * if 'setdefault', this ENGINE goes to the head of the list
 167          */
 168         if (!sk_ENGINE_push(fnd->sk, e))
 169             goto end;
 170         /* "touch" this ENGINE_PILE */
 171         fnd->uptodate = 0;
 172         if (setdefault) {
 173             if (!engine_unlocked_init(e)) {
 174                 ENGINEerr(ENGINE_F_ENGINE_TABLE_REGISTER,
 175                           ENGINE_R_INIT_FAILED);
 176                 goto end;
 177             }
 178             if (fnd->funct)
 179                 engine_unlocked_finish(fnd->funct, 0);
 180             fnd->funct = e;
 181             fnd->uptodate = 1;
 182         }
 183         nids++;
 184     }
 185     ret = 1;
 186  end:
 187     CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 188     return ret;
 189 }
 190
 191 static void int_unregister_cb_doall_arg(ENGINE_PILE *pile, ENGINE *e)
 192 {
 193     int n;
 194     /* Iterate the 'c->sk' stack removing any occurrence of 'e' */
 195     while ((n = sk_ENGINE_find(pile->sk, e)) >= 0) {
 196         (void)sk_ENGINE_delete(pile->sk, n);
 197         pile->uptodate = 0;
 198     }
 199     if (pile->funct == e) {
 200         engine_unlocked_finish(e, 0);
 201         pile->funct = NULL;
 202     }
 203 }
 204
 205 static IMPLEMENT_LHASH_DOALL_ARG_FN(int_unregister_cb, ENGINE_PILE, ENGINE)
 206
 207 void engine_table_unregister(ENGINE_TABLE **table, ENGINE *e)
 208 {
 209     CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 210     if (int_table_check(table, 0))
 211         lh_ENGINE_PILE_doall_arg(&(*table)->piles,
 212                                  LHASH_DOALL_ARG_FN(int_unregister_cb),
 213                                  ENGINE, e);
 214     CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 215 }
 216
 217 static void int_cleanup_cb_doall(ENGINE_PILE *p)
 218 {
 219     if (!p)
 220         return;
 221     sk_ENGINE_free(p->sk);
 222     if (p->funct)
 223         engine_unlocked_finish(p->funct, 0);
 224     OPENSSL_free(p);
 225 }
 226
 227 static IMPLEMENT_LHASH_DOALL_FN(int_cleanup_cb, ENGINE_PILE)
 228
 229 void engine_table_cleanup(ENGINE_TABLE **table)
 230 {
 231     CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 232     if (*table) {
 233         lh_ENGINE_PILE_doall(&(*table)->piles,
 234                              LHASH_DOALL_FN(int_cleanup_cb));
 235         lh_ENGINE_PILE_free(&(*table)->piles);
 236         *table = NULL;
 237     }
 238     CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 239 }
 240
 241 /* return a functional reference for a given 'nid' */
 242 #ifndef ENGINE_TABLE_DEBUG
 243 ENGINE *engine_table_select(ENGINE_TABLE **table, int nid)
 244 #else
 245 ENGINE *engine_table_select_tmp(ENGINE_TABLE **table, int nid, const char *f,
 246                                 int l)
 247 #endif
 248 {
 249     ENGINE *ret = NULL;
 250     ENGINE_PILE tmplate, *fnd = NULL;
 251     int initres, loop = 0;
 252
 253     if (!(*table)) {
 254 #ifdef ENGINE_TABLE_DEBUG
 255         fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, nothing "
 256                 "registered!\n", f, l, nid);
 257 #endif
 258         return NULL;
 259     }
 260     ERR_set_mark();
 261     CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 262     /*
 263      * Check again inside the lock otherwise we could race against cleanup
 264      * operations. But don't worry about a fprintf(stderr).
 265      */
 266     if (!int_table_check(table, 0))
 267         goto end;
 268     tmplate.nid = nid;
 269     fnd = lh_ENGINE_PILE_retrieve(&(*table)->piles, &tmplate);
 270     if (!fnd)
 271         goto end;
 272     if (fnd->funct && engine_unlocked_init(fnd->funct)) {
 273 #ifdef ENGINE_TABLE_DEBUG
 274         fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, using "
 275                 "ENGINE '%s' cached\n", f, l, nid, fnd->funct->id);
 276 #endif
 277         ret = fnd->funct;
 278         goto end;
 279     }
 280     if (fnd->uptodate) {
 281         ret = fnd->funct;
 282         goto end;
 283     }
 284  trynext:
 285     ret = sk_ENGINE_value(fnd->sk, loop++);
 286     if (!ret) {
 287 #ifdef ENGINE_TABLE_DEBUG
 288         fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, no "
 289                 "registered implementations would initialise\n", f, l, nid);
 290 #endif
 291         goto end;
 292     }
 293     /* Try to initialise the ENGINE? */
 294     if ((ret->funct_ref > 0) || !(table_flags & ENGINE_TABLE_FLAG_NOINIT))
 295         initres = engine_unlocked_init(ret);
 296     else
 297         initres = 0;
 298     if (initres) {
 299         /* Update 'funct' */
 300         if ((fnd->funct != ret) && engine_unlocked_init(ret)) {
 301             /* If there was a previous default we release it. */
 302             if (fnd->funct)
 303                 engine_unlocked_finish(fnd->funct, 0);
 304             fnd->funct = ret;
 305 #ifdef ENGINE_TABLE_DEBUG
 306             fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, "
 307                     "setting default to '%s'\n", f, l, nid, ret->id);
 308 #endif
 309         }
 310 #ifdef ENGINE_TABLE_DEBUG
 311         fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, using "
 312                 "newly initialised '%s'\n", f, l, nid, ret->id);
 313 #endif
 314         goto end;
 315     }
 316     goto trynext;
 317  end:
 318     /*
 319      * If it failed, it is unlikely to succeed again until some future
 320      * registrations have taken place. In all cases, we cache.
 321      */
 322     if (fnd)
 323         fnd->uptodate = 1;
 324 #ifdef ENGINE_TABLE_DEBUG
 325     if (ret)
 326         fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, caching "
 327                 "ENGINE '%s'\n", f, l, nid, ret->id);
 328     else
 329         fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, caching "
 330                 "'no matching ENGINE'\n", f, l, nid);
 331 #endif
 332     CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 333     /*
 334      * Whatever happened, any failed init()s are not failures in this
 335      * context, so clear our error state.
 336      */
 337     ERR_pop_to_mark();
 338     return ret;
 339 }
 340
 341 /* Table enumeration */
 342
 343 static void int_cb_doall_arg(ENGINE_PILE *pile, ENGINE_PILE_DOALL *dall)
 344 {
 345     dall->cb(pile->nid, pile->sk, pile->funct, dall->arg);
 346 }
 347
 348 static IMPLEMENT_LHASH_DOALL_ARG_FN(int_cb, ENGINE_PILE, ENGINE_PILE_DOALL)
 349
 350 void engine_table_doall(ENGINE_TABLE *table, engine_table_doall_cb *cb,
 351                         void *arg)
 352 {
 353     ENGINE_PILE_DOALL dall;
 354     dall.cb = cb;
 355     dall.arg = arg;
 356     if (table)
 357         lh_ENGINE_PILE_doall_arg(&table->piles,
 358                                  LHASH_DOALL_ARG_FN(int_cb),
 359                                  ENGINE_PILE_DOALL, &dall);
 360 }