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