1/*
2 * Copyright 2004-2023 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the Apache License 2.0 (the "License").  You may not use
5 * this file except in compliance with the License.  You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10#include "internal/cryptlib.h"
11#include <openssl/trace.h>
12#include <openssl/x509.h>
13#include <openssl/x509v3.h>
14
15#include "pcy_local.h"
16
17/*
18 * If the maximum number of nodes in the policy tree isn't defined, set it to
19 * a generous default of 1000 nodes.
20 *
21 * Defining this to be zero means unlimited policy tree growth which opens the
22 * door on CVE-2023-0464.
23 */
24#ifndef OPENSSL_POLICY_TREE_NODES_MAX
25# define OPENSSL_POLICY_TREE_NODES_MAX 1000
26#endif
27
28static void exnode_free(X509_POLICY_NODE *node);
29
30static void expected_print(BIO *channel,
31                           X509_POLICY_LEVEL *lev, X509_POLICY_NODE *node,
32                           int indent)
33{
34    if ((lev->flags & X509_V_FLAG_INHIBIT_MAP)
35        || !(node->data->flags & POLICY_DATA_FLAG_MAP_MASK))
36        BIO_puts(channel, "  Not Mapped\n");
37    else {
38        int i;
39
40        STACK_OF(ASN1_OBJECT) *pset = node->data->expected_policy_set;
41        ASN1_OBJECT *oid;
42        BIO_puts(channel, "  Expected: ");
43        for (i = 0; i < sk_ASN1_OBJECT_num(pset); i++) {
44            oid = sk_ASN1_OBJECT_value(pset, i);
45            if (i)
46                BIO_puts(channel, ", ");
47            i2a_ASN1_OBJECT(channel, oid);
48        }
49        BIO_puts(channel, "\n");
50    }
51}
52
53static void tree_print(BIO *channel,
54                       char *str, X509_POLICY_TREE *tree,
55                       X509_POLICY_LEVEL *curr)
56{
57    X509_POLICY_LEVEL *plev;
58
59    if (!curr)
60        curr = tree->levels + tree->nlevel;
61    else
62        curr++;
63
64    BIO_printf(channel, "Level print after %s\n", str);
65    BIO_printf(channel, "Printing Up to Level %ld\n",
66               (long)(curr - tree->levels));
67    for (plev = tree->levels; plev != curr; plev++) {
68        int i;
69
70        BIO_printf(channel, "Level %ld, flags = %x\n",
71                   (long)(plev - tree->levels), plev->flags);
72        for (i = 0; i < sk_X509_POLICY_NODE_num(plev->nodes); i++) {
73            X509_POLICY_NODE *node =
74                sk_X509_POLICY_NODE_value(plev->nodes, i);
75
76            X509_POLICY_NODE_print(channel, node, 2);
77            expected_print(channel, plev, node, 2);
78            BIO_printf(channel, "  Flags: %x\n", node->data->flags);
79        }
80        if (plev->anyPolicy)
81            X509_POLICY_NODE_print(channel, plev->anyPolicy, 2);
82    }
83}
84
85#define TREE_PRINT(str, tree, curr) \
86    OSSL_TRACE_BEGIN(X509V3_POLICY) { \
87        tree_print(trc_out, "before tree_prune()", tree, curr); \
88    } OSSL_TRACE_END(X509V3_POLICY)
89
90/*-
91 * Return value: <= 0 on error, or positive bit mask:
92 *
93 * X509_PCY_TREE_VALID: valid tree
94 * X509_PCY_TREE_EMPTY: empty tree (including bare TA case)
95 * X509_PCY_TREE_EXPLICIT: explicit policy required
96 */
97static int tree_init(X509_POLICY_TREE **ptree, STACK_OF(X509) *certs,
98                     unsigned int flags)
99{
100    X509_POLICY_TREE *tree;
101    X509_POLICY_LEVEL *level;
102    const X509_POLICY_CACHE *cache;
103    X509_POLICY_DATA *data = NULL;
104    int ret = X509_PCY_TREE_VALID;
105    int n = sk_X509_num(certs) - 1; /* RFC5280 paths omit the TA */
106    int explicit_policy = (flags & X509_V_FLAG_EXPLICIT_POLICY) ? 0 : n+1;
107    int any_skip = (flags & X509_V_FLAG_INHIBIT_ANY) ? 0 : n+1;
108    int map_skip = (flags & X509_V_FLAG_INHIBIT_MAP) ? 0 : n+1;
109    int i;
110
111    *ptree = NULL;
112
113    /* Can't do anything with just a trust anchor */
114    if (n == 0)
115        return X509_PCY_TREE_EMPTY;
116
117    /*
118     * First setup the policy cache in all n non-TA certificates, this will be
119     * used in X509_verify_cert() which will invoke the verify callback for all
120     * certificates with invalid policy extensions.
121     */
122    for (i = n - 1; i >= 0; i--) {
123        X509 *x = sk_X509_value(certs, i);
124
125        /* Call for side-effect of computing hash and caching extensions */
126        X509_check_purpose(x, -1, 0);
127
128        /* If cache is NULL, likely ENOMEM: return immediately */
129        if (ossl_policy_cache_set(x) == NULL)
130            return X509_PCY_TREE_INTERNAL;
131    }
132
133    /*
134     * At this point check for invalid policies and required explicit policy.
135     * Note that the explicit_policy counter is a count-down to zero, with the
136     * requirement kicking in if and once it does that.  The counter is
137     * decremented for every non-self-issued certificate in the path, but may
138     * be further reduced by policy constraints in a non-leaf certificate.
139     *
140     * The ultimate policy set is the intersection of all the policies along
141     * the path, if we hit a certificate with an empty policy set, and explicit
142     * policy is required we're done.
143     */
144    for (i = n - 1;
145         i >= 0 && (explicit_policy > 0 || (ret & X509_PCY_TREE_EMPTY) == 0);
146         i--) {
147        X509 *x = sk_X509_value(certs, i);
148        uint32_t ex_flags = X509_get_extension_flags(x);
149
150        /* All the policies are already cached, we can return early */
151        if (ex_flags & EXFLAG_INVALID_POLICY)
152            return X509_PCY_TREE_INVALID;
153
154        /* Access the cache which we now know exists */
155        cache = ossl_policy_cache_set(x);
156
157        if ((ret & X509_PCY_TREE_VALID) && cache->data == NULL)
158            ret = X509_PCY_TREE_EMPTY;
159        if (explicit_policy > 0) {
160            if (!(ex_flags & EXFLAG_SI))
161                explicit_policy--;
162            if ((cache->explicit_skip >= 0)
163                && (cache->explicit_skip < explicit_policy))
164                explicit_policy = cache->explicit_skip;
165        }
166    }
167
168    if (explicit_policy == 0)
169        ret |= X509_PCY_TREE_EXPLICIT;
170    if ((ret & X509_PCY_TREE_VALID) == 0)
171        return ret;
172
173    /* If we get this far initialize the tree */
174    if ((tree = OPENSSL_zalloc(sizeof(*tree))) == NULL) {
175        ERR_raise(ERR_LIB_X509V3, ERR_R_MALLOC_FAILURE);
176        return X509_PCY_TREE_INTERNAL;
177    }
178
179    /* Limit the growth of the tree to mitigate CVE-2023-0464 */
180    tree->node_maximum = OPENSSL_POLICY_TREE_NODES_MAX;
181
182    /*
183     * http://tools.ietf.org/html/rfc5280#section-6.1.2, figure 3.
184     *
185     * The top level is implicitly for the trust anchor with valid expected
186     * policies of anyPolicy.  (RFC 5280 has the TA at depth 0 and the leaf at
187     * depth n, we have the leaf at depth 0 and the TA at depth n).
188     */
189    if ((tree->levels = OPENSSL_zalloc(sizeof(*tree->levels)*(n+1))) == NULL) {
190        OPENSSL_free(tree);
191        ERR_raise(ERR_LIB_X509V3, ERR_R_MALLOC_FAILURE);
192        return X509_PCY_TREE_INTERNAL;
193    }
194    tree->nlevel = n+1;
195    level = tree->levels;
196    if ((data = ossl_policy_data_new(NULL,
197                                     OBJ_nid2obj(NID_any_policy), 0)) == NULL)
198        goto bad_tree;
199    if (ossl_policy_level_add_node(level, data, NULL, tree, 1) == NULL) {
200        ossl_policy_data_free(data);
201        goto bad_tree;
202    }
203
204    /*
205     * In this pass initialize all the tree levels and whether anyPolicy and
206     * policy mapping are inhibited at each level.
207     */
208    for (i = n - 1; i >= 0; i--) {
209        X509 *x = sk_X509_value(certs, i);
210        uint32_t ex_flags = X509_get_extension_flags(x);
211
212        /* Access the cache which we now know exists */
213        cache = ossl_policy_cache_set(x);
214
215        X509_up_ref(x);
216        (++level)->cert = x;
217
218        if (!cache->anyPolicy)
219            level->flags |= X509_V_FLAG_INHIBIT_ANY;
220
221        /* Determine inhibit any and inhibit map flags */
222        if (any_skip == 0) {
223            /*
224             * Any matching allowed only if certificate is self issued and not
225             * the last in the chain.
226             */
227            if (!(ex_flags & EXFLAG_SI) || (i == 0))
228                level->flags |= X509_V_FLAG_INHIBIT_ANY;
229        } else {
230            if (!(ex_flags & EXFLAG_SI))
231                any_skip--;
232            if ((cache->any_skip >= 0) && (cache->any_skip < any_skip))
233                any_skip = cache->any_skip;
234        }
235
236        if (map_skip == 0)
237            level->flags |= X509_V_FLAG_INHIBIT_MAP;
238        else {
239            if (!(ex_flags & EXFLAG_SI))
240                map_skip--;
241            if ((cache->map_skip >= 0) && (cache->map_skip < map_skip))
242                map_skip = cache->map_skip;
243        }
244    }
245
246    *ptree = tree;
247    return ret;
248
249 bad_tree:
250    X509_policy_tree_free(tree);
251    return X509_PCY_TREE_INTERNAL;
252}
253
254/*
255 * Return value: 1 on success, 0 otherwise
256 */
257static int tree_link_matching_nodes(X509_POLICY_LEVEL *curr,
258                                    X509_POLICY_DATA *data,
259                                    X509_POLICY_TREE *tree)
260{
261    X509_POLICY_LEVEL *last = curr - 1;
262    int i, matched = 0;
263
264    /* Iterate through all in nodes linking matches */
265    for (i = 0; i < sk_X509_POLICY_NODE_num(last->nodes); i++) {
266        X509_POLICY_NODE *node = sk_X509_POLICY_NODE_value(last->nodes, i);
267
268        if (ossl_policy_node_match(last, node, data->valid_policy)) {
269            if (ossl_policy_level_add_node(curr, data, node, tree, 0) == NULL)
270                return 0;
271            matched = 1;
272        }
273    }
274    if (!matched && last->anyPolicy) {
275        if (ossl_policy_level_add_node(curr, data, last->anyPolicy, tree, 0) == NULL)
276            return 0;
277    }
278    return 1;
279}
280
281/*
282 * This corresponds to RFC3280 6.1.3(d)(1): link any data from
283 * CertificatePolicies onto matching parent or anyPolicy if no match.
284 *
285 * Return value: 1 on success, 0 otherwise.
286 */
287static int tree_link_nodes(X509_POLICY_LEVEL *curr,
288                           const X509_POLICY_CACHE *cache,
289                           X509_POLICY_TREE *tree)
290{
291    int i;
292
293    for (i = 0; i < sk_X509_POLICY_DATA_num(cache->data); i++) {
294        X509_POLICY_DATA *data = sk_X509_POLICY_DATA_value(cache->data, i);
295
296        /* Look for matching nodes in previous level */
297        if (!tree_link_matching_nodes(curr, data, tree))
298            return 0;
299    }
300    return 1;
301}
302
303/*
304 * This corresponds to RFC3280 6.1.3(d)(2): Create new data for any unmatched
305 * policies in the parent and link to anyPolicy.
306 *
307 * Return value: 1 on success, 0 otherwise.
308 */
309static int tree_add_unmatched(X509_POLICY_LEVEL *curr,
310                              const X509_POLICY_CACHE *cache,
311                              const ASN1_OBJECT *id,
312                              X509_POLICY_NODE *node, X509_POLICY_TREE *tree)
313{
314    X509_POLICY_DATA *data;
315
316    if (id == NULL)
317        id = node->data->valid_policy;
318    /*
319     * Create a new node with qualifiers from anyPolicy and id from unmatched
320     * node.
321     */
322    if ((data = ossl_policy_data_new(NULL, id, node_critical(node))) == NULL)
323        return 0;
324
325    /* Curr may not have anyPolicy */
326    data->qualifier_set = cache->anyPolicy->qualifier_set;
327    data->flags |= POLICY_DATA_FLAG_SHARED_QUALIFIERS;
328    if (ossl_policy_level_add_node(curr, data, node, tree, 1) == NULL) {
329        ossl_policy_data_free(data);
330        return 0;
331    }
332    return 1;
333}
334
335/*
336 * Return value: 1 on success, 0 otherwise.
337 */
338static int tree_link_unmatched(X509_POLICY_LEVEL *curr,
339                               const X509_POLICY_CACHE *cache,
340                               X509_POLICY_NODE *node, X509_POLICY_TREE *tree)
341{
342    const X509_POLICY_LEVEL *last = curr - 1;
343    int i;
344
345    if ((last->flags & X509_V_FLAG_INHIBIT_MAP)
346        || !(node->data->flags & POLICY_DATA_FLAG_MAPPED)) {
347        /* If no policy mapping: matched if one child present */
348        if (node->nchild)
349            return 1;
350        if (!tree_add_unmatched(curr, cache, NULL, node, tree))
351            return 0;
352        /* Add it */
353    } else {
354        /* If mapping: matched if one child per expected policy set */
355        STACK_OF(ASN1_OBJECT) *expset = node->data->expected_policy_set;
356        if (node->nchild == sk_ASN1_OBJECT_num(expset))
357            return 1;
358        /* Locate unmatched nodes */
359        for (i = 0; i < sk_ASN1_OBJECT_num(expset); i++) {
360            ASN1_OBJECT *oid = sk_ASN1_OBJECT_value(expset, i);
361            if (ossl_policy_level_find_node(curr, node, oid))
362                continue;
363            if (!tree_add_unmatched(curr, cache, oid, node, tree))
364                return 0;
365        }
366
367    }
368    return 1;
369}
370
371/*
372 * Return value: 1 on success, 0 otherwise
373 */
374static int tree_link_any(X509_POLICY_LEVEL *curr,
375                         const X509_POLICY_CACHE *cache,
376                         X509_POLICY_TREE *tree)
377{
378    int i;
379    X509_POLICY_NODE *node;
380    X509_POLICY_LEVEL *last = curr - 1;
381
382    for (i = 0; i < sk_X509_POLICY_NODE_num(last->nodes); i++) {
383        node = sk_X509_POLICY_NODE_value(last->nodes, i);
384
385        if (!tree_link_unmatched(curr, cache, node, tree))
386            return 0;
387    }
388    /* Finally add link to anyPolicy */
389    if (last->anyPolicy &&
390            ossl_policy_level_add_node(curr, cache->anyPolicy,
391                                       last->anyPolicy, tree, 0) == NULL)
392        return 0;
393    return 1;
394}
395
396/*-
397 * Prune the tree: delete any child mapped child data on the current level then
398 * proceed up the tree deleting any data with no children. If we ever have no
399 * data on a level we can halt because the tree will be empty.
400 *
401 * Return value: <= 0 error, otherwise one of:
402 *
403 * X509_PCY_TREE_VALID: valid tree
404 * X509_PCY_TREE_EMPTY: empty tree
405 */
406static int tree_prune(X509_POLICY_TREE *tree, X509_POLICY_LEVEL *curr)
407{
408    STACK_OF(X509_POLICY_NODE) *nodes;
409    X509_POLICY_NODE *node;
410    int i;
411    nodes = curr->nodes;
412    if (curr->flags & X509_V_FLAG_INHIBIT_MAP) {
413        for (i = sk_X509_POLICY_NODE_num(nodes) - 1; i >= 0; i--) {
414            node = sk_X509_POLICY_NODE_value(nodes, i);
415            /* Delete any mapped data: see RFC3280 XXXX */
416            if (node->data->flags & POLICY_DATA_FLAG_MAP_MASK) {
417                node->parent->nchild--;
418                OPENSSL_free(node);
419                (void)sk_X509_POLICY_NODE_delete(nodes, i);
420            }
421        }
422    }
423
424    for (;;) {
425        --curr;
426        nodes = curr->nodes;
427        for (i = sk_X509_POLICY_NODE_num(nodes) - 1; i >= 0; i--) {
428            node = sk_X509_POLICY_NODE_value(nodes, i);
429            if (node->nchild == 0) {
430                node->parent->nchild--;
431                OPENSSL_free(node);
432                (void)sk_X509_POLICY_NODE_delete(nodes, i);
433            }
434        }
435        if (curr->anyPolicy && !curr->anyPolicy->nchild) {
436            if (curr->anyPolicy->parent)
437                curr->anyPolicy->parent->nchild--;
438            OPENSSL_free(curr->anyPolicy);
439            curr->anyPolicy = NULL;
440        }
441        if (curr == tree->levels) {
442            /* If we zapped anyPolicy at top then tree is empty */
443            if (!curr->anyPolicy)
444                return X509_PCY_TREE_EMPTY;
445            break;
446        }
447    }
448    return X509_PCY_TREE_VALID;
449}
450
451/*
452 * Return value: 1 on success, 0 otherwise.
453 */
454static int tree_add_auth_node(STACK_OF(X509_POLICY_NODE) **pnodes,
455                              X509_POLICY_NODE *pcy)
456{
457    if (*pnodes == NULL &&
458        (*pnodes = ossl_policy_node_cmp_new()) == NULL)
459        return 0;
460    if (sk_X509_POLICY_NODE_find(*pnodes, pcy) >= 0)
461        return 1;
462    return sk_X509_POLICY_NODE_push(*pnodes, pcy) != 0;
463}
464
465#define TREE_CALC_FAILURE 0
466#define TREE_CALC_OK_NOFREE 1
467#define TREE_CALC_OK_DOFREE 2
468
469/*-
470 * Calculate the authority set based on policy tree. The 'pnodes' parameter is
471 * used as a store for the set of policy nodes used to calculate the user set.
472 * If the authority set is not anyPolicy then pnodes will just point to the
473 * authority set. If however the authority set is anyPolicy then the set of
474 * valid policies (other than anyPolicy) is store in pnodes.
475 *
476 * Return value:
477 *  TREE_CALC_FAILURE on failure,
478 *  TREE_CALC_OK_NOFREE on success and pnodes need not be freed,
479 *  TREE_CALC_OK_DOFREE on success and pnodes needs to be freed
480 */
481static int tree_calculate_authority_set(X509_POLICY_TREE *tree,
482                                        STACK_OF(X509_POLICY_NODE) **pnodes)
483{
484    X509_POLICY_LEVEL *curr;
485    X509_POLICY_NODE *node, *anyptr;
486    STACK_OF(X509_POLICY_NODE) **addnodes;
487    int i, j;
488    curr = tree->levels + tree->nlevel - 1;
489
490    /* If last level contains anyPolicy set is anyPolicy */
491    if (curr->anyPolicy) {
492        if (!tree_add_auth_node(&tree->auth_policies, curr->anyPolicy))
493            return TREE_CALC_FAILURE;
494        addnodes = pnodes;
495    } else
496        /* Add policies to authority set */
497        addnodes = &tree->auth_policies;
498
499    curr = tree->levels;
500    for (i = 1; i < tree->nlevel; i++) {
501        /*
502         * If no anyPolicy node on this level it can't appear on lower
503         * levels so end search.
504         */
505        if ((anyptr = curr->anyPolicy) == NULL)
506            break;
507        curr++;
508        for (j = 0; j < sk_X509_POLICY_NODE_num(curr->nodes); j++) {
509            node = sk_X509_POLICY_NODE_value(curr->nodes, j);
510            if ((node->parent == anyptr)
511                && !tree_add_auth_node(addnodes, node)) {
512                if (addnodes == pnodes) {
513                    sk_X509_POLICY_NODE_free(*pnodes);
514                    *pnodes = NULL;
515                }
516                return TREE_CALC_FAILURE;
517            }
518        }
519    }
520    if (addnodes == pnodes)
521        return TREE_CALC_OK_DOFREE;
522
523    *pnodes = tree->auth_policies;
524    return TREE_CALC_OK_NOFREE;
525}
526
527/*
528 * Return value: 1 on success, 0 otherwise.
529 */
530static int tree_calculate_user_set(X509_POLICY_TREE *tree,
531                                   STACK_OF(ASN1_OBJECT) *policy_oids,
532                                   STACK_OF(X509_POLICY_NODE) *auth_nodes)
533{
534    int i;
535    X509_POLICY_NODE *node;
536    ASN1_OBJECT *oid;
537    X509_POLICY_NODE *anyPolicy;
538    X509_POLICY_DATA *extra;
539
540    /*
541     * Check if anyPolicy present in authority constrained policy set: this
542     * will happen if it is a leaf node.
543     */
544    if (sk_ASN1_OBJECT_num(policy_oids) <= 0)
545        return 1;
546
547    anyPolicy = tree->levels[tree->nlevel - 1].anyPolicy;
548
549    for (i = 0; i < sk_ASN1_OBJECT_num(policy_oids); i++) {
550        oid = sk_ASN1_OBJECT_value(policy_oids, i);
551        if (OBJ_obj2nid(oid) == NID_any_policy) {
552            tree->flags |= POLICY_FLAG_ANY_POLICY;
553            return 1;
554        }
555    }
556
557    for (i = 0; i < sk_ASN1_OBJECT_num(policy_oids); i++) {
558        oid = sk_ASN1_OBJECT_value(policy_oids, i);
559        node = ossl_policy_tree_find_sk(auth_nodes, oid);
560        if (!node) {
561            if (!anyPolicy)
562                continue;
563            /*
564             * Create a new node with policy ID from user set and qualifiers
565             * from anyPolicy.
566             */
567            extra = ossl_policy_data_new(NULL, oid, node_critical(anyPolicy));
568            if (extra == NULL)
569                return 0;
570            extra->qualifier_set = anyPolicy->data->qualifier_set;
571            extra->flags = POLICY_DATA_FLAG_SHARED_QUALIFIERS
572                | POLICY_DATA_FLAG_EXTRA_NODE;
573            node = ossl_policy_level_add_node(NULL, extra, anyPolicy->parent,
574                                              tree, 1);
575            if (node == NULL) {
576                ossl_policy_data_free(extra);
577                return 0;
578            }
579        }
580        if (!tree->user_policies) {
581            tree->user_policies = sk_X509_POLICY_NODE_new_null();
582            if (!tree->user_policies) {
583                exnode_free(node);
584                return 0;
585            }
586        }
587        if (!sk_X509_POLICY_NODE_push(tree->user_policies, node)) {
588            exnode_free(node);
589            return 0;
590        }
591    }
592    return 1;
593}
594
595/*-
596 * Return value: <= 0 error, otherwise one of:
597 *  X509_PCY_TREE_VALID: valid tree
598 *  X509_PCY_TREE_EMPTY: empty tree
599 * (see tree_prune()).
600 */
601static int tree_evaluate(X509_POLICY_TREE *tree)
602{
603    int ret, i;
604    X509_POLICY_LEVEL *curr = tree->levels + 1;
605    const X509_POLICY_CACHE *cache;
606
607    for (i = 1; i < tree->nlevel; i++, curr++) {
608        cache = ossl_policy_cache_set(curr->cert);
609        if (!tree_link_nodes(curr, cache, tree))
610            return X509_PCY_TREE_INTERNAL;
611
612        if (!(curr->flags & X509_V_FLAG_INHIBIT_ANY)
613            && !tree_link_any(curr, cache, tree))
614            return X509_PCY_TREE_INTERNAL;
615        TREE_PRINT("before tree_prune()", tree, curr);
616        ret = tree_prune(tree, curr);
617        if (ret != X509_PCY_TREE_VALID)
618            return ret;
619    }
620    return X509_PCY_TREE_VALID;
621}
622
623static void exnode_free(X509_POLICY_NODE *node)
624{
625    if (node->data && (node->data->flags & POLICY_DATA_FLAG_EXTRA_NODE))
626        OPENSSL_free(node);
627}
628
629void X509_policy_tree_free(X509_POLICY_TREE *tree)
630{
631    X509_POLICY_LEVEL *curr;
632    int i;
633
634    if (!tree)
635        return;
636
637    sk_X509_POLICY_NODE_free(tree->auth_policies);
638    sk_X509_POLICY_NODE_pop_free(tree->user_policies, exnode_free);
639
640    for (i = 0, curr = tree->levels; i < tree->nlevel; i++, curr++) {
641        X509_free(curr->cert);
642        sk_X509_POLICY_NODE_pop_free(curr->nodes, ossl_policy_node_free);
643        ossl_policy_node_free(curr->anyPolicy);
644    }
645
646    sk_X509_POLICY_DATA_pop_free(tree->extra_data, ossl_policy_data_free);
647    OPENSSL_free(tree->levels);
648    OPENSSL_free(tree);
649
650}
651
652/*-
653 * Application policy checking function.
654 * Return codes:
655 *  X509_PCY_TREE_FAILURE:  Failure to satisfy explicit policy
656 *  X509_PCY_TREE_INVALID:  Inconsistent or invalid extensions
657 *  X509_PCY_TREE_INTERNAL: Internal error, most likely malloc
658 *  X509_PCY_TREE_VALID:    Success (null tree if empty or bare TA)
659 */
660int X509_policy_check(X509_POLICY_TREE **ptree, int *pexplicit_policy,
661                      STACK_OF(X509) *certs,
662                      STACK_OF(ASN1_OBJECT) *policy_oids, unsigned int flags)
663{
664    int init_ret;
665    int ret;
666    int calc_ret;
667    X509_POLICY_TREE *tree = NULL;
668    STACK_OF(X509_POLICY_NODE) *nodes, *auth_nodes = NULL;
669
670    *ptree = NULL;
671    *pexplicit_policy = 0;
672    init_ret = tree_init(&tree, certs, flags);
673
674    if (init_ret <= 0)
675        return init_ret;
676
677    if ((init_ret & X509_PCY_TREE_EXPLICIT) == 0) {
678        if (init_ret & X509_PCY_TREE_EMPTY) {
679            X509_policy_tree_free(tree);
680            return X509_PCY_TREE_VALID;
681        }
682    } else {
683        *pexplicit_policy = 1;
684        /* Tree empty and requireExplicit True: Error */
685        if (init_ret & X509_PCY_TREE_EMPTY)
686            return X509_PCY_TREE_FAILURE;
687    }
688
689    ret = tree_evaluate(tree);
690    TREE_PRINT("tree_evaluate()", tree, NULL);
691    if (ret <= 0)
692        goto error;
693
694    if (ret == X509_PCY_TREE_EMPTY) {
695        X509_policy_tree_free(tree);
696        if (init_ret & X509_PCY_TREE_EXPLICIT)
697            return X509_PCY_TREE_FAILURE;
698        return X509_PCY_TREE_VALID;
699    }
700
701    /* Tree is not empty: continue */
702
703    if ((calc_ret = tree_calculate_authority_set(tree, &auth_nodes)) == 0)
704        goto error;
705    ret = tree_calculate_user_set(tree, policy_oids, auth_nodes);
706    if (calc_ret == TREE_CALC_OK_DOFREE)
707        sk_X509_POLICY_NODE_free(auth_nodes);
708    if (!ret)
709        goto error;
710
711    *ptree = tree;
712
713    if (init_ret & X509_PCY_TREE_EXPLICIT) {
714        nodes = X509_policy_tree_get0_user_policies(tree);
715        if (sk_X509_POLICY_NODE_num(nodes) <= 0)
716            return X509_PCY_TREE_FAILURE;
717    }
718    return X509_PCY_TREE_VALID;
719
720 error:
721    X509_policy_tree_free(tree);
722    return X509_PCY_TREE_INTERNAL;
723}
724