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 "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         {
  63         /* The 'nid' of this algorithm/mode */
  64         int nid;
  65         /* ENGINEs that implement this algorithm/mode. */
  66         STACK_OF(ENGINE) *sk;
  67         /* The default ENGINE to perform this algorithm/mode. */
  68         ENGINE *funct;
  69         /* Zero if 'sk' is newer than the cached 'funct', non-zero otherwise */
  70         int uptodate;
  71         } ENGINE_PILE;
  72
  73 /* The type exposed in eng_int.h */
  74 struct st_engine_table
  75         {
  76         LHASH piles;
  77         }; /* ENGINE_TABLE */
  78
  79 /* Global flags (ENGINE_TABLE_FLAG_***). */
  80 static unsigned int table_flags = 0;
  81
  82 /* API function manipulating 'table_flags' */
  83 unsigned int ENGINE_get_table_flags(void)
  84         {
  85         return table_flags;
  86         }
  87 void ENGINE_set_table_flags(unsigned int flags)
  88         {
  89         table_flags = flags;
  90         }
  91
  92 /* Internal functions for the "piles" hash table */
  93 static unsigned long engine_pile_hash(const ENGINE_PILE *c)
  94         {
  95         return c->nid;
  96         }
  97 static int engine_pile_cmp(const ENGINE_PILE *a, const ENGINE_PILE *b)
  98         {
  99         return a->nid - b->nid;
 100         }
 101 static IMPLEMENT_LHASH_HASH_FN(engine_pile_hash, const ENGINE_PILE *)
 102 static IMPLEMENT_LHASH_COMP_FN(engine_pile_cmp, const ENGINE_PILE *)
 103 static int int_table_check(ENGINE_TABLE **t, int create)
 104         {
 105         LHASH *lh;
 106         if(*t) return 1;
 107         if(!create) return 0;
 108         if((lh = lh_new(LHASH_HASH_FN(engine_pile_hash),
 109                         LHASH_COMP_FN(engine_pile_cmp))) == NULL)
 110                 return 0;
 111         *t = (ENGINE_TABLE *)lh;
 112         return 1;
 113         }
 114
 115 /* Privately exposed (via eng_int.h) functions for adding and/or removing
 116  * ENGINEs from the implementation table */
 117 int engine_table_register(ENGINE_TABLE **table, ENGINE_CLEANUP_CB *cleanup,
 118                 ENGINE *e, const int *nids, int num_nids, int setdefault)
 119         {
 120         int ret = 0, added = 0;
 121         ENGINE_PILE tmplate, *fnd;
 122         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 123         if(!(*table))
 124                 added = 1;
 125         if(!int_table_check(table, 1))
 126                 goto end;
 127         if(added)
 128                 /* The cleanup callback needs to be added */
 129                 engine_cleanup_add_first(cleanup);
 130         while(num_nids--)
 131                 {
 132                 tmplate.nid = *nids;
 133                 fnd = lh_retrieve(&(*table)->piles, &tmplate);
 134                 if(!fnd)
 135                         {
 136                         fnd = OPENSSL_malloc(sizeof(ENGINE_PILE));
 137                         if(!fnd) goto end;
 138                         fnd->uptodate = 0;
 139                         fnd->nid = *nids;
 140                         fnd->sk = sk_ENGINE_new_null();
 141                         if(!fnd->sk)
 142                                 {
 143                                 OPENSSL_free(fnd);
 144                                 goto end;
 145                                 }
 146                         fnd->funct = NULL;
 147                         lh_insert(&(*table)->piles, fnd);
 148                         }
 149                 /* A registration shouldn't add duplciate entries */
 150                 sk_ENGINE_delete_ptr(fnd->sk, e);
 151                 /* if 'setdefault', this ENGINE goes to the head of the list */
 152                 if(!sk_ENGINE_push(fnd->sk, e))
 153                         goto end;
 154                 /* "touch" this ENGINE_PILE */
 155                 fnd->uptodate = 1;
 156                 if(setdefault)
 157                         {
 158                         if(!engine_unlocked_init(e))
 159                                 {
 160                                 ENGINEerr(ENGINE_F_ENGINE_TABLE_REGISTER,
 161                                                 ENGINE_R_INIT_FAILED);
 162                                 goto end;
 163                                 }
 164                         if(fnd->funct)
 165                                 engine_unlocked_finish(fnd->funct, 0);
 166                         fnd->funct = e;
 167                         }
 168                 nids++;
 169                 }
 170         ret = 1;
 171 end:
 172         CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 173         return ret;
 174         }
 175 static void int_unregister_cb(ENGINE_PILE *pile, ENGINE *e)
 176         {
 177         int n;
 178         /* Iterate the 'c->sk' stack removing any occurance of 'e' */
 179         while((n = sk_ENGINE_find(pile->sk, e)) >= 0)
 180                 {
 181                 sk_ENGINE_delete(pile->sk, n);
 182                 /* "touch" this ENGINE_CIPHER */
 183                 pile->uptodate = 1;
 184                 }
 185         if(pile->funct == e)
 186                 {
 187                 engine_unlocked_finish(e, 0);
 188                 pile->funct = NULL;
 189                 }
 190         }
 191 static IMPLEMENT_LHASH_DOALL_ARG_FN(int_unregister_cb,ENGINE_PILE *,ENGINE *)
 192 void engine_table_unregister(ENGINE_TABLE **table, ENGINE *e)
 193         {
 194         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 195         if(int_table_check(table, 0))
 196                 lh_doall_arg(&(*table)->piles,
 197                         LHASH_DOALL_ARG_FN(int_unregister_cb), e);
 198         CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 199         }
 200
 201 static void int_cleanup_cb(ENGINE_PILE *p)
 202         {
 203         sk_ENGINE_free(p->sk);
 204         if(p->funct)
 205                 engine_unlocked_finish(p->funct, 0);
 206         OPENSSL_free(p);
 207         }
 208 static IMPLEMENT_LHASH_DOALL_FN(int_cleanup_cb,ENGINE_PILE *)
 209 void engine_table_cleanup(ENGINE_TABLE **table)
 210         {
 211         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 212         if(*table)
 213                 {
 214                 lh_doall(&(*table)->piles, LHASH_DOALL_FN(int_cleanup_cb));
 215                 lh_free(&(*table)->piles);
 216                 *table = NULL;
 217                 }
 218         CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 219         }
 220
 221 /* return a functional reference for a given 'nid' */
 222 #ifndef ENGINE_TABLE_DEBUG
 223 ENGINE *engine_table_select(ENGINE_TABLE **table, int nid)
 224 #else
 225 ENGINE *engine_table_select_tmp(ENGINE_TABLE **table, int nid, const char *f, int l)
 226 #endif
 227         {
 228         ENGINE *ret = NULL;
 229         ENGINE_PILE tmplate, *fnd=NULL;
 230         int initres, loop = 0;
 231
 232         if(!(*table))
 233                 {
 234 #ifdef ENGINE_TABLE_DEBUG
 235                 fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, nothing "
 236                         "registered!\n", f, l, nid);
 237 #endif
 238                 return NULL;
 239                 }
 240         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 241         /* Check again inside the lock otherwise we could race against cleanup
 242          * operations. But don't worry about a fprintf(stderr). */
 243         if(!int_table_check(table, 0)) goto end;
 244         tmplate.nid = nid;
 245         fnd = lh_retrieve(&(*table)->piles, &tmplate);
 246         if(!fnd) goto end;
 247         if(fnd->funct && engine_unlocked_init(fnd->funct))
 248                 {
 249 #ifdef ENGINE_TABLE_DEBUG
 250                 fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, using "
 251                         "ENGINE '%s' cached\n", f, l, nid, fnd->funct->id);
 252 #endif
 253                 ret = fnd->funct;
 254                 goto end;
 255                 }
 256         if(fnd->uptodate)
 257                 {
 258                 ret = fnd->funct;
 259                 goto end;
 260                 }
 261 trynext:
 262         ret = sk_ENGINE_value(fnd->sk, loop++);
 263         if(!ret)
 264                 {
 265 #ifdef ENGINE_TABLE_DEBUG
 266                 fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, no "
 267                                 "registered implementations would initialise\n",
 268                                 f, l, nid);
 269 #endif
 270                 goto end;
 271                 }
 272         /* Try to initialise the ENGINE? */
 273         if((ret->funct_ref > 0) || !(table_flags & ENGINE_TABLE_FLAG_NOINIT))
 274                 initres = engine_unlocked_init(ret);
 275         else
 276                 initres = 0;
 277         if(initres)
 278                 {
 279                 /* Update 'funct' */
 280                 if((fnd->funct != ret) && engine_unlocked_init(ret))
 281                         {
 282                         /* If there was a previous default we release it. */
 283                         if(fnd->funct)
 284                                 engine_unlocked_finish(fnd->funct, 0);
 285                         fnd->funct = ret;
 286 #ifdef ENGINE_TABLE_DEBUG
 287                         fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, "
 288                                 "setting default to '%s'\n", f, l, nid, ret->id);
 289 #endif
 290                         }
 291 #ifdef ENGINE_TABLE_DEBUG
 292                 fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, using "
 293                                 "newly initialised '%s'\n", f, l, nid, ret->id);
 294 #endif
 295                 goto end;
 296                 }
 297         goto trynext;
 298 end:
 299         /* If it failed, it is unlikely to succeed again until some future
 300          * registrations have taken place. In all cases, we cache. */
 301         if(fnd) fnd->uptodate = 1;
 302 #ifdef ENGINE_TABLE_DEBUG
 303         if(ret)
 304                 fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, caching "
 305                                 "ENGINE '%s'\n", f, l, nid, ret->id);
 306         else
 307                 fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, caching "
 308                                 "'no matching ENGINE'\n", f, l, nid);
 309 #endif
 310         CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 311         /* Whatever happened, any failed init()s are not failures in this
 312          * context, so clear our error state. */
 313         ERR_clear_error();
 314         return ret;
 315         }