crypto/x509v3/pcy_tree.c

   1 /* pcy_tree.c */
   2 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
   3  * project 2004.
   4  */
   5 /* ====================================================================
   6  * Copyright (c) 2004 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 #include "cryptlib.h"
  60 #include <openssl/x509.h>
  61 #include <openssl/x509v3.h>
  62
  63 #include "pcy_int.h"
  64
  65 /* Enable this to print out the complete policy tree at various point during
  66  * evaluation.
  67  */
  68
  69 /*#define OPENSSL_POLICY_DEBUG*/
  70
  71 #ifdef OPENSSL_POLICY_DEBUG
  72
  73 static void expected_print(BIO *err, X509_POLICY_LEVEL *lev,
  74                                 X509_POLICY_NODE *node, int indent)
  75         {
  76         if (        (lev->flags & X509_V_FLAG_INHIBIT_MAP)
  77                 || !(node->data->flags & POLICY_DATA_FLAG_MAP_MASK))
  78                 BIO_puts(err, "  Not Mapped\n");
  79         else
  80                 {
  81                 int i;
  82                 STACK_OF(ASN1_OBJECT) *pset = node->data->expected_policy_set;
  83                 ASN1_OBJECT *oid;
  84                 BIO_puts(err, "  Expected: ");
  85                 for (i = 0; i < sk_ASN1_OBJECT_num(pset); i++)
  86                         {
  87                         oid = sk_ASN1_OBJECT_value(pset, i);
  88                         if (i)
  89                                 BIO_puts(err, ", ");
  90                         i2a_ASN1_OBJECT(err, oid);
  91                         }
  92                 BIO_puts(err, "\n");
  93                 }
  94         }
  95
  96 static void tree_print(char *str, X509_POLICY_TREE *tree,
  97                         X509_POLICY_LEVEL *curr)
  98         {
  99         X509_POLICY_LEVEL *plev;
 100         X509_POLICY_NODE *node;
 101         int i;
 102         BIO *err;
 103         err = BIO_new_fp(stderr, BIO_NOCLOSE);
 104         if (err == NULL)
 105                 return;
 106         if (!curr)
 107                 curr = tree->levels + tree->nlevel;
 108         else
 109                 curr++;
 110         BIO_printf(err, "Level print after %s\n", str);
 111         BIO_printf(err, "Printing Up to Level %ld\n", curr - tree->levels);
 112         for (plev = tree->levels; plev != curr; plev++)
 113                 {
 114                 BIO_printf(err, "Level %ld, flags = %x\n",
 115                                 plev - tree->levels, plev->flags);
 116                 for (i = 0; i < sk_X509_POLICY_NODE_num(plev->nodes); i++)
 117                         {
 118                         node = sk_X509_POLICY_NODE_value(plev->nodes, i);
 119                         X509_POLICY_NODE_print(err, node, 2);
 120                         expected_print(err, plev, node, 2);
 121                         BIO_printf(err, "  Flags: %x\n", node->data->flags);
 122                         }
 123                 if (plev->anyPolicy)
 124                         X509_POLICY_NODE_print(err, plev->anyPolicy, 2);
 125                 }
 126
 127         BIO_free(err);
 128
 129         }
 130 #else
 131
 132 #define tree_print(a,b,c) /* */
 133
 134 #endif
 135
 136 /* Initialize policy tree. Return values:
 137  *  0 Some internal error occurred.
 138  * -1 Inconsistent or invalid extensions in certificates.
 139  *  1 Tree initialized OK.
 140  *  2 Policy tree is empty.
 141  *  5 Tree OK and requireExplicitPolicy true.
 142  *  6 Tree empty and requireExplicitPolicy true.
 143  */
 144
 145 static int tree_init(X509_POLICY_TREE **ptree, STACK_OF(X509) *certs,
 146                         unsigned int flags)
 147         {
 148         X509_POLICY_TREE *tree;
 149         X509_POLICY_LEVEL *level;
 150         const X509_POLICY_CACHE *cache;
 151         X509_POLICY_DATA *data = NULL;
 152         X509 *x;
 153         int ret = 1;
 154         int i, n;
 155         int explicit_policy;
 156         int any_skip;
 157         int map_skip;
 158         *ptree = NULL;
 159         n = sk_X509_num(certs);
 160
 161 #if 0
 162         /* Disable policy mapping for now... */
 163         flags |= X509_V_FLAG_INHIBIT_MAP;
 164 #endif
 165
 166         if (flags & X509_V_FLAG_EXPLICIT_POLICY)
 167                 explicit_policy = 0;
 168         else
 169                 explicit_policy = n + 1;
 170
 171         if (flags & X509_V_FLAG_INHIBIT_ANY)
 172                 any_skip = 0;
 173         else
 174                 any_skip = n + 1;
 175
 176         if (flags & X509_V_FLAG_INHIBIT_MAP)
 177                 map_skip = 0;
 178         else
 179                 map_skip = n + 1;
 180
 181         /* Can't do anything with just a trust anchor */
 182         if (n == 1)
 183                 return 1;
 184         /* First setup policy cache in all certificates apart from the
 185          * trust anchor. Note any bad cache results on the way. Also can
 186          * calculate explicit_policy value at this point.
 187          */
 188         for (i = n - 2; i >= 0; i--)
 189                 {
 190                 x = sk_X509_value(certs, i);
 191                 X509_check_purpose(x, -1, -1);
 192                 cache = policy_cache_set(x);
 193                 /* If cache NULL something bad happened: return immediately */
 194                 if (cache == NULL)
 195                         return 0;
 196                 /* If inconsistent extensions keep a note of it but continue */
 197                 if (x->ex_flags & EXFLAG_INVALID_POLICY)
 198                         ret = -1;
 199                 /* Otherwise if we have no data (hence no CertificatePolicies)
 200                  * and haven't already set an inconsistent code note it.
 201                  */
 202                 else if ((ret == 1) && !cache->data)
 203                         ret = 2;
 204                 if (explicit_policy > 0)
 205                         {
 206                         if (!(x->ex_flags & EXFLAG_SI))
 207                                 explicit_policy--;
 208                         if ((cache->explicit_skip != -1)
 209                                 && (cache->explicit_skip < explicit_policy))
 210                                 explicit_policy = cache->explicit_skip;
 211                         }
 212                 }
 213
 214         if (ret != 1)
 215                 {
 216                 if (ret == 2 && !explicit_policy)
 217                         return 6;
 218                 return ret;
 219                 }
 220
 221
 222         /* If we get this far initialize the tree */
 223
 224         tree = OPENSSL_malloc(sizeof(X509_POLICY_TREE));
 225
 226         if (!tree)
 227                 return 0;
 228
 229         tree->flags = 0;
 230         tree->levels = OPENSSL_malloc(sizeof(X509_POLICY_LEVEL) * n);
 231         tree->nlevel = 0;
 232         tree->extra_data = NULL;
 233         tree->auth_policies = NULL;
 234         tree->user_policies = NULL;
 235
 236         if (!tree->levels)
 237                 {
 238                 OPENSSL_free(tree);
 239                 return 0;
 240                 }
 241
 242         memset(tree->levels, 0, n * sizeof(X509_POLICY_LEVEL));
 243
 244         tree->nlevel = n;
 245
 246         level = tree->levels;
 247
 248         /* Root data: initialize to anyPolicy */
 249
 250         data = policy_data_new(NULL, OBJ_nid2obj(NID_any_policy), 0);
 251
 252         if (!data || !level_add_node(level, data, NULL, tree))
 253                 goto bad_tree;
 254
 255         for (i = n - 2; i >= 0; i--)
 256                 {
 257                 level++;
 258                 x = sk_X509_value(certs, i);
 259                 cache = policy_cache_set(x);
 260                 CRYPTO_add(&x->references, 1, CRYPTO_LOCK_X509);
 261                 level->cert = x;
 262
 263                 if (!cache->anyPolicy)
 264                                 level->flags |= X509_V_FLAG_INHIBIT_ANY;
 265
 266                 /* Determine inhibit any and inhibit map flags */
 267                 if (any_skip == 0)
 268                         {
 269                         /* Any matching allowed if certificate is self
 270                          * issued and not the last in the chain.
 271                          */
 272                         if (!(x->ex_flags & EXFLAG_SI) || (i == 0))
 273                                 level->flags |= X509_V_FLAG_INHIBIT_ANY;
 274                         }
 275                 else
 276                         {
 277                         if (!(x->ex_flags & EXFLAG_SI))
 278                                 any_skip--;
 279                         if ((cache->any_skip >= 0)
 280                                 && (cache->any_skip < any_skip))
 281                                 any_skip = cache->any_skip;
 282                         }
 283
 284                 if (map_skip == 0)
 285                         level->flags |= X509_V_FLAG_INHIBIT_MAP;
 286                 else
 287                         {
 288                         if (!(x->ex_flags & EXFLAG_SI))
 289                                 map_skip--;
 290                         if ((cache->map_skip >= 0)
 291                                 && (cache->map_skip < map_skip))
 292                                 map_skip = cache->map_skip;
 293                         }
 294
 295                 }
 296
 297         *ptree = tree;
 298
 299         if (explicit_policy)
 300                 return 1;
 301         else
 302                 return 5;
 303
 304         bad_tree:
 305
 306         X509_policy_tree_free(tree);
 307
 308         return 0;
 309
 310         }
 311
 312 static int tree_link_matching_nodes(X509_POLICY_LEVEL *curr,
 313                                 const X509_POLICY_DATA *data)
 314         {
 315         X509_POLICY_LEVEL *last = curr - 1;
 316         X509_POLICY_NODE *node;
 317         int i, matched = 0;
 318         /* Iterate through all in nodes linking matches */
 319         for (i = 0; i < sk_X509_POLICY_NODE_num(last->nodes); i++)
 320                 {
 321                 node = sk_X509_POLICY_NODE_value(last->nodes, i);
 322                 if (policy_node_match(last, node, data->valid_policy))
 323                         {
 324                         if (!level_add_node(curr, data, node, NULL))
 325                                 return 0;
 326                         matched = 1;
 327                         }
 328                 }
 329         if (!matched && last->anyPolicy)
 330                 {
 331                 if (!level_add_node(curr, data, last->anyPolicy, NULL))
 332                         return 0;
 333                 }
 334         return 1;
 335         }
 336
 337 /* This corresponds to RFC3280 6.1.3(d)(1):
 338  * link any data from CertificatePolicies onto matching parent
 339  * or anyPolicy if no match.
 340  */
 341
 342 static int tree_link_nodes(X509_POLICY_LEVEL *curr,
 343                                 const X509_POLICY_CACHE *cache)
 344         {
 345         int i;
 346         X509_POLICY_DATA *data;
 347
 348         for (i = 0; i < sk_X509_POLICY_DATA_num(cache->data); i++)
 349                 {
 350                 data = sk_X509_POLICY_DATA_value(cache->data, i);
 351                 /* If a node is mapped any it doesn't have a corresponding
 352                  * CertificatePolicies entry.
 353                  * However such an identical node would be created
 354                  * if anyPolicy matching is enabled because there would be
 355                  * no match with the parent valid_policy_set. So we create
 356                  * link because then it will have the mapping flags
 357                  * right and we can prune it later.
 358                  */
 359 #if 0
 360                 if ((data->flags & POLICY_DATA_FLAG_MAPPED_ANY)
 361                         && !(curr->flags & X509_V_FLAG_INHIBIT_ANY))
 362                         continue;
 363 #endif
 364                 /* Look for matching nodes in previous level */
 365                 if (!tree_link_matching_nodes(curr, data))
 366                                 return 0;
 367                 }
 368         return 1;
 369         }
 370
 371 /* This corresponds to RFC3280 6.1.3(d)(2):
 372  * Create new data for any unmatched policies in the parent and link
 373  * to anyPolicy.
 374  */
 375
 376 static int tree_add_unmatched(X509_POLICY_LEVEL *curr,
 377                         const X509_POLICY_CACHE *cache,
 378                         const ASN1_OBJECT *id,
 379                         X509_POLICY_NODE *node,
 380                         X509_POLICY_TREE *tree)
 381         {
 382         X509_POLICY_DATA *data;
 383         if (id == NULL)
 384                 id = node->data->valid_policy;
 385         /* Create a new node with qualifiers from anyPolicy and
 386          * id from unmatched node.
 387          */
 388         data = policy_data_new(NULL, id, node_critical(node));
 389
 390         if (data == NULL)
 391                 return 0;
 392         /* Curr may not have anyPolicy */
 393         data->qualifier_set = cache->anyPolicy->qualifier_set;
 394         data->flags |= POLICY_DATA_FLAG_SHARED_QUALIFIERS;
 395         if (!level_add_node(curr, data, node, tree))
 396                 {
 397                 policy_data_free(data);
 398                 return 0;
 399                 }
 400
 401         return 1;
 402         }
 403
 404 static int tree_link_unmatched(X509_POLICY_LEVEL *curr,
 405                         const X509_POLICY_CACHE *cache,
 406                         X509_POLICY_NODE *node,
 407                         X509_POLICY_TREE *tree)
 408         {
 409         const X509_POLICY_LEVEL *last = curr - 1;
 410         int i;
 411
 412         if (        (last->flags & X509_V_FLAG_INHIBIT_MAP)
 413                 || !(node->data->flags & POLICY_DATA_FLAG_MAPPED))
 414                 {
 415                 /* If no policy mapping: matched if one child present */
 416                 if (node->nchild)
 417                         return 1;
 418                 if (!tree_add_unmatched(curr, cache, NULL, node, tree))
 419                         return 0;
 420                 /* Add it */
 421                 }
 422         else
 423                 {
 424                 /* If mapping: matched if one child per expected policy set */
 425                 STACK_OF(ASN1_OBJECT) *expset = node->data->expected_policy_set;
 426                 if (node->nchild == sk_ASN1_OBJECT_num(expset))
 427                         return 1;
 428                 /* Locate unmatched nodes */
 429                 for (i = 0; i < sk_ASN1_OBJECT_num(expset); i++)
 430                         {
 431                         ASN1_OBJECT *oid = sk_ASN1_OBJECT_value(expset, i);
 432                         if (level_find_node(curr, node, oid))
 433                                 continue;
 434                         if (!tree_add_unmatched(curr, cache, oid, node, tree))
 435                                 return 0;
 436                         }
 437
 438                 }
 439
 440         return 1;
 441
 442         }
 443
 444 static int tree_link_any(X509_POLICY_LEVEL *curr,
 445                         const X509_POLICY_CACHE *cache,
 446                         X509_POLICY_TREE *tree)
 447         {
 448         int i;
 449         /*X509_POLICY_DATA *data;*/
 450         X509_POLICY_NODE *node;
 451         X509_POLICY_LEVEL *last = curr - 1;
 452
 453         for (i = 0; i < sk_X509_POLICY_NODE_num(last->nodes); i++)
 454                 {
 455                 node = sk_X509_POLICY_NODE_value(last->nodes, i);
 456
 457                 if (!tree_link_unmatched(curr, cache, node, tree))
 458                         return 0;
 459
 460 #if 0
 461
 462                 /* Skip any node with any children: we only want unmathced
 463                  * nodes.
 464                  *
 465                  * Note: need something better for policy mapping
 466                  * because each node may have multiple children
 467                  */
 468                 if (node->nchild)
 469                         continue;
 470
 471                 /* Create a new node with qualifiers from anyPolicy and
 472                  * id from unmatched node.
 473                  */
 474                 data = policy_data_new(NULL, node->data->valid_policy,
 475                                                 node_critical(node));
 476
 477                 if (data == NULL)
 478                         return 0;
 479                 /* Curr may not have anyPolicy */
 480                 data->qualifier_set = cache->anyPolicy->qualifier_set;
 481                 data->flags |= POLICY_DATA_FLAG_SHARED_QUALIFIERS;
 482                 if (!level_add_node(curr, data, node, tree))
 483                         {
 484                         policy_data_free(data);
 485                         return 0;
 486                         }
 487
 488 #endif
 489
 490                 }
 491         /* Finally add link to anyPolicy */
 492         if (last->anyPolicy)
 493                 {
 494                 if (!level_add_node(curr, cache->anyPolicy,
 495                                                 last->anyPolicy, NULL))
 496                         return 0;
 497                 }
 498         return 1;
 499         }
 500
 501 /* Prune the tree: delete any child mapped child data on the current level
 502  * then proceed up the tree deleting any data with no children. If we ever
 503  * have no data on a level we can halt because the tree will be empty.
 504  */
 505
 506 static int tree_prune(X509_POLICY_TREE *tree, X509_POLICY_LEVEL *curr)
 507         {
 508         STACK_OF(X509_POLICY_NODE) *nodes;
 509         X509_POLICY_NODE *node;
 510         int i;
 511         nodes = curr->nodes;
 512         if (curr->flags & X509_V_FLAG_INHIBIT_MAP)
 513                 {
 514                 for (i = sk_X509_POLICY_NODE_num(nodes) - 1; i >= 0; i--)
 515                         {
 516                         node = sk_X509_POLICY_NODE_value(nodes, i);
 517                         /* Delete any mapped data: see RFC3280 XXXX */
 518                         if (node->data->flags & POLICY_DATA_FLAG_MAP_MASK)
 519                                 {
 520                                 node->parent->nchild--;
 521                                 OPENSSL_free(node);
 522                                 (void)sk_X509_POLICY_NODE_delete(nodes,i);
 523                                 }
 524                         }
 525                 }
 526
 527         for(;;) {
 528                 --curr;
 529                 nodes = curr->nodes;
 530                 for (i = sk_X509_POLICY_NODE_num(nodes) - 1; i >= 0; i--)
 531                         {
 532                         node = sk_X509_POLICY_NODE_value(nodes, i);
 533                         if (node->nchild == 0)
 534                                 {
 535                                 node->parent->nchild--;
 536                                 OPENSSL_free(node);
 537                                 (void)sk_X509_POLICY_NODE_delete(nodes, i);
 538                                 }
 539                         }
 540                 if (curr->anyPolicy && !curr->anyPolicy->nchild)
 541                         {
 542                         if (curr->anyPolicy->parent)
 543                                 curr->anyPolicy->parent->nchild--;
 544                         OPENSSL_free(curr->anyPolicy);
 545                         curr->anyPolicy = NULL;
 546                         }
 547                 if (curr == tree->levels)
 548                         {
 549                         /* If we zapped anyPolicy at top then tree is empty */
 550                         if (!curr->anyPolicy)
 551                                         return 2;
 552                         return 1;
 553                         }
 554                 }
 555
 556         return 1;
 557
 558         }
 559
 560 static int tree_add_auth_node(STACK_OF(X509_POLICY_NODE) **pnodes,
 561                                                  X509_POLICY_NODE *pcy)
 562         {
 563         if (!*pnodes)
 564                 {
 565                 *pnodes = policy_node_cmp_new();
 566                 if (!*pnodes)
 567                         return 0;
 568                 }
 569         else if (sk_X509_POLICY_NODE_find(*pnodes, pcy) != -1)
 570                 return 1;
 571
 572         if (!sk_X509_POLICY_NODE_push(*pnodes, pcy))
 573                 return 0;
 574
 575         return 1;
 576
 577         }
 578
 579 /* Calculate the authority set based on policy tree.
 580  * The 'pnodes' parameter is used as a store for the set of policy nodes
 581  * used to calculate the user set. If the authority set is not anyPolicy
 582  * then pnodes will just point to the authority set. If however the authority
 583  * set is anyPolicy then the set of valid policies (other than anyPolicy)
 584  * is store in pnodes. The return value of '2' is used in this case to indicate
 585  * that pnodes should be freed.
 586  */
 587
 588 static int tree_calculate_authority_set(X509_POLICY_TREE *tree,
 589                                         STACK_OF(X509_POLICY_NODE) **pnodes)
 590         {
 591         X509_POLICY_LEVEL *curr;
 592         X509_POLICY_NODE *node, *anyptr;
 593         STACK_OF(X509_POLICY_NODE) **addnodes;
 594         int i, j;
 595         curr = tree->levels + tree->nlevel - 1;
 596
 597         /* If last level contains anyPolicy set is anyPolicy */
 598         if (curr->anyPolicy)
 599                 {
 600                 if (!tree_add_auth_node(&tree->auth_policies, curr->anyPolicy))
 601                         return 0;
 602                 addnodes = pnodes;
 603                 }
 604         else
 605                 /* Add policies to authority set */
 606                 addnodes = &tree->auth_policies;
 607
 608         curr = tree->levels;
 609         for (i = 1; i < tree->nlevel; i++)
 610                 {
 611                 /* If no anyPolicy node on this this level it can't
 612                  * appear on lower levels so end search.
 613                  */
 614                 if (!(anyptr = curr->anyPolicy))
 615                         break;
 616                 curr++;
 617                 for (j = 0; j < sk_X509_POLICY_NODE_num(curr->nodes); j++)
 618                         {
 619                         node = sk_X509_POLICY_NODE_value(curr->nodes, j);
 620                         if ((node->parent == anyptr)
 621                                 && !tree_add_auth_node(addnodes, node))
 622                                         return 0;
 623                         }
 624                 }
 625
 626         if (addnodes == pnodes)
 627                 return 2;
 628
 629         *pnodes = tree->auth_policies;
 630
 631         return 1;
 632         }
 633
 634 static int tree_calculate_user_set(X509_POLICY_TREE *tree,
 635                                 STACK_OF(ASN1_OBJECT) *policy_oids,
 636                                 STACK_OF(X509_POLICY_NODE) *auth_nodes)
 637         {
 638         int i;
 639         X509_POLICY_NODE *node;
 640         ASN1_OBJECT *oid;
 641
 642         X509_POLICY_NODE *anyPolicy;
 643         X509_POLICY_DATA *extra;
 644
 645         /* Check if anyPolicy present in authority constrained policy set:
 646          * this will happen if it is a leaf node.
 647          */
 648
 649         if (sk_ASN1_OBJECT_num(policy_oids) <= 0)
 650                 return 1;
 651
 652         anyPolicy = tree->levels[tree->nlevel - 1].anyPolicy;
 653
 654         for (i = 0; i < sk_ASN1_OBJECT_num(policy_oids); i++)
 655                 {
 656                 oid = sk_ASN1_OBJECT_value(policy_oids, i);
 657                 if (OBJ_obj2nid(oid) == NID_any_policy)
 658                         {
 659                         tree->flags |= POLICY_FLAG_ANY_POLICY;
 660                         return 1;
 661                         }
 662                 }
 663
 664         for (i = 0; i < sk_ASN1_OBJECT_num(policy_oids); i++)
 665                 {
 666                 oid = sk_ASN1_OBJECT_value(policy_oids, i);
 667                 node = tree_find_sk(auth_nodes, oid);
 668                 if (!node)
 669                         {
 670                         if (!anyPolicy)
 671                                 continue;
 672                         /* Create a new node with policy ID from user set
 673                          * and qualifiers from anyPolicy.
 674                          */
 675                         extra = policy_data_new(NULL, oid,
 676                                                 node_critical(anyPolicy));
 677                         if (!extra)
 678                                 return 0;
 679                         extra->qualifier_set = anyPolicy->data->qualifier_set;
 680                         extra->flags = POLICY_DATA_FLAG_SHARED_QUALIFIERS
 681                                                 | POLICY_DATA_FLAG_EXTRA_NODE;
 682                         node = level_add_node(NULL, extra, anyPolicy->parent,
 683                                                 tree);
 684                         }
 685                 if (!tree->user_policies)
 686                         {
 687                         tree->user_policies = sk_X509_POLICY_NODE_new_null();
 688                         if (!tree->user_policies)
 689                                 return 1;
 690                         }
 691                 if (!sk_X509_POLICY_NODE_push(tree->user_policies, node))
 692                         return 0;
 693                 }
 694         return 1;
 695
 696         }
 697
 698 static int tree_evaluate(X509_POLICY_TREE *tree)
 699         {
 700         int ret, i;
 701         X509_POLICY_LEVEL *curr = tree->levels + 1;
 702         const X509_POLICY_CACHE *cache;
 703
 704         for(i = 1; i < tree->nlevel; i++, curr++)
 705                 {
 706                 cache = policy_cache_set(curr->cert);
 707                 if (!tree_link_nodes(curr, cache))
 708                         return 0;
 709
 710                 if (!(curr->flags & X509_V_FLAG_INHIBIT_ANY)
 711                         && !tree_link_any(curr, cache, tree))
 712                         return 0;
 713         tree_print("before tree_prune()", tree, curr);
 714                 ret = tree_prune(tree, curr);
 715                 if (ret != 1)
 716                         return ret;
 717                 }
 718
 719         return 1;
 720
 721         }
 722
 723 static void exnode_free(X509_POLICY_NODE *node)
 724         {
 725         if (node->data && (node->data->flags & POLICY_DATA_FLAG_EXTRA_NODE))
 726                 OPENSSL_free(node);
 727         }
 728
 729
 730 void X509_policy_tree_free(X509_POLICY_TREE *tree)
 731         {
 732         X509_POLICY_LEVEL *curr;
 733         int i;
 734
 735         if (!tree)
 736                 return;
 737
 738         sk_X509_POLICY_NODE_free(tree->auth_policies);
 739         sk_X509_POLICY_NODE_pop_free(tree->user_policies, exnode_free);
 740
 741         for(i = 0, curr = tree->levels; i < tree->nlevel; i++, curr++)
 742                 {
 743                 if (curr->cert)
 744                         X509_free(curr->cert);
 745                 if (curr->nodes)
 746                         sk_X509_POLICY_NODE_pop_free(curr->nodes,
 747                                                 policy_node_free);
 748                 if (curr->anyPolicy)
 749                         policy_node_free(curr->anyPolicy);
 750                 }
 751
 752         if (tree->extra_data)
 753                 sk_X509_POLICY_DATA_pop_free(tree->extra_data,
 754                                                 policy_data_free);
 755
 756         OPENSSL_free(tree->levels);
 757         OPENSSL_free(tree);
 758
 759         }
 760
 761 /*-
 762  * Application policy checking function.
 763  * Return codes:
 764  *  0   Internal Error.
 765  *  1   Successful.
 766  * -1   One or more certificates contain invalid or inconsistent extensions
 767  * -2   User constrained policy set empty and requireExplicit true.
 768  */
 769
 770 int X509_policy_check(X509_POLICY_TREE **ptree, int *pexplicit_policy,
 771                         STACK_OF(X509) *certs,
 772                         STACK_OF(ASN1_OBJECT) *policy_oids,
 773                         unsigned int flags)
 774         {
 775         int ret;
 776         X509_POLICY_TREE *tree = NULL;
 777         STACK_OF(X509_POLICY_NODE) *nodes, *auth_nodes = NULL;
 778         *ptree = NULL;
 779
 780         *pexplicit_policy = 0;
 781         ret = tree_init(&tree, certs, flags);
 782
 783         switch (ret)
 784                 {
 785
 786                 /* Tree empty requireExplicit False: OK */
 787                 case 2:
 788                 return 1;
 789
 790                 /* Some internal error */
 791                 case -1:
 792                 return -1;
 793
 794                 /* Some internal error */
 795                 case 0:
 796                 return 0;
 797
 798                 /* Tree empty requireExplicit True: Error */
 799
 800                 case 6:
 801                 *pexplicit_policy = 1;
 802                 return -2;
 803
 804                 /* Tree OK requireExplicit True: OK and continue */
 805                 case 5:
 806                 *pexplicit_policy = 1;
 807                 break;
 808
 809                 /* Tree OK: continue */
 810
 811                 case 1:
 812                 if (!tree)
 813                         /*
 814                          * tree_init() returns success and a null tree
 815                          * if it's just looking at a trust anchor.
 816                          * I'm not sure that returning success here is
 817                          * correct, but I'm sure that reporting this
 818                          * as an internal error which our caller
 819                          * interprets as a malloc failure is wrong.
 820                          */
 821                         return 1;
 822                 break;
 823                 }
 824
 825         if (!tree) goto error;
 826         ret = tree_evaluate(tree);
 827
 828         tree_print("tree_evaluate()", tree, NULL);
 829
 830         if (ret <= 0)
 831                 goto error;
 832
 833         /* Return value 2 means tree empty */
 834         if (ret == 2)
 835                 {
 836                 X509_policy_tree_free(tree);
 837                 if (*pexplicit_policy)
 838                         return -2;
 839                 else
 840                         return 1;
 841                 }
 842
 843         /* Tree is not empty: continue */
 844
 845         ret = tree_calculate_authority_set(tree, &auth_nodes);
 846
 847         if (!ret)
 848                 goto error;
 849
 850         if (!tree_calculate_user_set(tree, policy_oids, auth_nodes))
 851                 goto error;
 852
 853         if (ret == 2)
 854                 sk_X509_POLICY_NODE_free(auth_nodes);
 855
 856         if (tree)
 857                 *ptree = tree;
 858
 859         if (*pexplicit_policy)
 860                 {
 861                 nodes = X509_policy_tree_get0_user_policies(tree);
 862                 if (sk_X509_POLICY_NODE_num(nodes) <= 0)
 863                         return -2;
 864                 }
 865
 866         return 1;
 867
 868         error:
 869
 870         X509_policy_tree_free(tree);
 871
 872         return 0;
 873
 874         }
 875