1/*
2 * Copyright 2006-2024 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/*
11 * Implementation of RFC 3779 section 3.2.
12 */
13
14#include <assert.h>
15#include <stdio.h>
16#include <string.h>
17#include "internal/cryptlib.h"
18#include <openssl/conf.h>
19#include <openssl/asn1.h>
20#include <openssl/asn1t.h>
21#include <openssl/x509v3.h>
22#include <openssl/x509.h>
23#include "crypto/x509.h"
24#include <openssl/bn.h>
25#include "ext_dat.h"
26#include "x509_local.h"
27
28#ifndef OPENSSL_NO_RFC3779
29
30/*
31 * OpenSSL ASN.1 template translation of RFC 3779 3.2.3.
32 */
33
34ASN1_SEQUENCE(ASRange) = {
35  ASN1_SIMPLE(ASRange, min, ASN1_INTEGER),
36  ASN1_SIMPLE(ASRange, max, ASN1_INTEGER)
37} ASN1_SEQUENCE_END(ASRange)
38
39ASN1_CHOICE(ASIdOrRange) = {
40  ASN1_SIMPLE(ASIdOrRange, u.id,    ASN1_INTEGER),
41  ASN1_SIMPLE(ASIdOrRange, u.range, ASRange)
42} ASN1_CHOICE_END(ASIdOrRange)
43
44ASN1_CHOICE(ASIdentifierChoice) = {
45  ASN1_SIMPLE(ASIdentifierChoice,      u.inherit,       ASN1_NULL),
46  ASN1_SEQUENCE_OF(ASIdentifierChoice, u.asIdsOrRanges, ASIdOrRange)
47} ASN1_CHOICE_END(ASIdentifierChoice)
48
49ASN1_SEQUENCE(ASIdentifiers) = {
50  ASN1_EXP_OPT(ASIdentifiers, asnum, ASIdentifierChoice, 0),
51  ASN1_EXP_OPT(ASIdentifiers, rdi,   ASIdentifierChoice, 1)
52} ASN1_SEQUENCE_END(ASIdentifiers)
53
54IMPLEMENT_ASN1_FUNCTIONS(ASRange)
55IMPLEMENT_ASN1_FUNCTIONS(ASIdOrRange)
56IMPLEMENT_ASN1_FUNCTIONS(ASIdentifierChoice)
57IMPLEMENT_ASN1_FUNCTIONS(ASIdentifiers)
58
59/*
60 * i2r method for an ASIdentifierChoice.
61 */
62static int i2r_ASIdentifierChoice(BIO *out,
63                                  ASIdentifierChoice *choice,
64                                  int indent, const char *msg)
65{
66    int i;
67    char *s;
68    if (choice == NULL)
69        return 1;
70    BIO_printf(out, "%*s%s:\n", indent, "", msg);
71    switch (choice->type) {
72    case ASIdentifierChoice_inherit:
73        BIO_printf(out, "%*sinherit\n", indent + 2, "");
74        break;
75    case ASIdentifierChoice_asIdsOrRanges:
76        for (i = 0; i < sk_ASIdOrRange_num(choice->u.asIdsOrRanges); i++) {
77            ASIdOrRange *aor =
78                sk_ASIdOrRange_value(choice->u.asIdsOrRanges, i);
79            switch (aor->type) {
80            case ASIdOrRange_id:
81                if ((s = i2s_ASN1_INTEGER(NULL, aor->u.id)) == NULL)
82                    return 0;
83                BIO_printf(out, "%*s%s\n", indent + 2, "", s);
84                OPENSSL_free(s);
85                break;
86            case ASIdOrRange_range:
87                if ((s = i2s_ASN1_INTEGER(NULL, aor->u.range->min)) == NULL)
88                    return 0;
89                BIO_printf(out, "%*s%s-", indent + 2, "", s);
90                OPENSSL_free(s);
91                if ((s = i2s_ASN1_INTEGER(NULL, aor->u.range->max)) == NULL)
92                    return 0;
93                BIO_printf(out, "%s\n", s);
94                OPENSSL_free(s);
95                break;
96            default:
97                return 0;
98            }
99        }
100        break;
101    default:
102        return 0;
103    }
104    return 1;
105}
106
107/*
108 * i2r method for an ASIdentifier extension.
109 */
110static int i2r_ASIdentifiers(const X509V3_EXT_METHOD *method,
111                             void *ext, BIO *out, int indent)
112{
113    ASIdentifiers *asid = ext;
114    return (i2r_ASIdentifierChoice(out, asid->asnum, indent,
115                                   "Autonomous System Numbers") &&
116            i2r_ASIdentifierChoice(out, asid->rdi, indent,
117                                   "Routing Domain Identifiers"));
118}
119
120/*
121 * Sort comparison function for a sequence of ASIdOrRange elements.
122 */
123static int ASIdOrRange_cmp(const ASIdOrRange *const *a_,
124                           const ASIdOrRange *const *b_)
125{
126    const ASIdOrRange *a = *a_, *b = *b_;
127
128    assert((a->type == ASIdOrRange_id && a->u.id != NULL) ||
129           (a->type == ASIdOrRange_range && a->u.range != NULL &&
130            a->u.range->min != NULL && a->u.range->max != NULL));
131
132    assert((b->type == ASIdOrRange_id && b->u.id != NULL) ||
133           (b->type == ASIdOrRange_range && b->u.range != NULL &&
134            b->u.range->min != NULL && b->u.range->max != NULL));
135
136    if (a->type == ASIdOrRange_id && b->type == ASIdOrRange_id)
137        return ASN1_INTEGER_cmp(a->u.id, b->u.id);
138
139    if (a->type == ASIdOrRange_range && b->type == ASIdOrRange_range) {
140        int r = ASN1_INTEGER_cmp(a->u.range->min, b->u.range->min);
141        return r != 0 ? r : ASN1_INTEGER_cmp(a->u.range->max,
142                                             b->u.range->max);
143    }
144
145    if (a->type == ASIdOrRange_id)
146        return ASN1_INTEGER_cmp(a->u.id, b->u.range->min);
147    else
148        return ASN1_INTEGER_cmp(a->u.range->min, b->u.id);
149}
150
151/*
152 * Add an inherit element.
153 */
154int X509v3_asid_add_inherit(ASIdentifiers *asid, int which)
155{
156    ASIdentifierChoice **choice;
157    if (asid == NULL)
158        return 0;
159    switch (which) {
160    case V3_ASID_ASNUM:
161        choice = &asid->asnum;
162        break;
163    case V3_ASID_RDI:
164        choice = &asid->rdi;
165        break;
166    default:
167        return 0;
168    }
169    if (*choice == NULL) {
170        if ((*choice = ASIdentifierChoice_new()) == NULL)
171            return 0;
172        if (((*choice)->u.inherit = ASN1_NULL_new()) == NULL) {
173            ASIdentifierChoice_free(*choice);
174            *choice = NULL;
175            return 0;
176        }
177        (*choice)->type = ASIdentifierChoice_inherit;
178    }
179    return (*choice)->type == ASIdentifierChoice_inherit;
180}
181
182/*
183 * Add an ID or range to an ASIdentifierChoice.
184 */
185int X509v3_asid_add_id_or_range(ASIdentifiers *asid,
186                                int which, ASN1_INTEGER *min, ASN1_INTEGER *max)
187{
188    ASIdentifierChoice **choice;
189    ASIdOrRange *aor;
190    if (asid == NULL)
191        return 0;
192    switch (which) {
193    case V3_ASID_ASNUM:
194        choice = &asid->asnum;
195        break;
196    case V3_ASID_RDI:
197        choice = &asid->rdi;
198        break;
199    default:
200        return 0;
201    }
202    if (*choice != NULL && (*choice)->type != ASIdentifierChoice_asIdsOrRanges)
203        return 0;
204    if (*choice == NULL) {
205        if ((*choice = ASIdentifierChoice_new()) == NULL)
206            return 0;
207        (*choice)->u.asIdsOrRanges = sk_ASIdOrRange_new(ASIdOrRange_cmp);
208        if ((*choice)->u.asIdsOrRanges == NULL) {
209            ASIdentifierChoice_free(*choice);
210            *choice = NULL;
211            return 0;
212        }
213        (*choice)->type = ASIdentifierChoice_asIdsOrRanges;
214    }
215    if ((aor = ASIdOrRange_new()) == NULL)
216        return 0;
217    if (!sk_ASIdOrRange_reserve((*choice)->u.asIdsOrRanges, 1))
218        goto err;
219    if (max == NULL) {
220        aor->type = ASIdOrRange_id;
221        aor->u.id = min;
222    } else {
223        aor->type = ASIdOrRange_range;
224        if ((aor->u.range = ASRange_new()) == NULL)
225            goto err;
226        ASN1_INTEGER_free(aor->u.range->min);
227        aor->u.range->min = min;
228        ASN1_INTEGER_free(aor->u.range->max);
229        aor->u.range->max = max;
230    }
231    /* Cannot fail due to the reservation above */
232    if (!ossl_assert(sk_ASIdOrRange_push((*choice)->u.asIdsOrRanges, aor)))
233        goto err;
234    return 1;
235
236 err:
237    ASIdOrRange_free(aor);
238    return 0;
239}
240
241/*
242 * Extract min and max values from an ASIdOrRange.
243 */
244static int extract_min_max(ASIdOrRange *aor,
245                           ASN1_INTEGER **min, ASN1_INTEGER **max)
246{
247    if (!ossl_assert(aor != NULL))
248        return 0;
249    switch (aor->type) {
250    case ASIdOrRange_id:
251        *min = aor->u.id;
252        *max = aor->u.id;
253        return 1;
254    case ASIdOrRange_range:
255        *min = aor->u.range->min;
256        *max = aor->u.range->max;
257        return 1;
258    }
259
260    return 0;
261}
262
263/*
264 * Check whether an ASIdentifierChoice is in canonical form.
265 */
266static int ASIdentifierChoice_is_canonical(ASIdentifierChoice *choice)
267{
268    ASN1_INTEGER *a_max_plus_one = NULL;
269    ASN1_INTEGER *orig;
270    BIGNUM *bn = NULL;
271    int i, ret = 0;
272
273    /*
274     * Empty element or inheritance is canonical.
275     */
276    if (choice == NULL || choice->type == ASIdentifierChoice_inherit)
277        return 1;
278
279    /*
280     * If not a list, or if empty list, it's broken.
281     */
282    if (choice->type != ASIdentifierChoice_asIdsOrRanges ||
283        sk_ASIdOrRange_num(choice->u.asIdsOrRanges) == 0)
284        return 0;
285
286    /*
287     * It's a list, check it.
288     */
289    for (i = 0; i < sk_ASIdOrRange_num(choice->u.asIdsOrRanges) - 1; i++) {
290        ASIdOrRange *a = sk_ASIdOrRange_value(choice->u.asIdsOrRanges, i);
291        ASIdOrRange *b = sk_ASIdOrRange_value(choice->u.asIdsOrRanges, i + 1);
292        ASN1_INTEGER *a_min = NULL, *a_max = NULL, *b_min = NULL, *b_max =
293            NULL;
294
295        if (!extract_min_max(a, &a_min, &a_max)
296                || !extract_min_max(b, &b_min, &b_max))
297            goto done;
298
299        /*
300         * Punt misordered list, overlapping start, or inverted range.
301         */
302        if (ASN1_INTEGER_cmp(a_min, b_min) >= 0 ||
303            ASN1_INTEGER_cmp(a_min, a_max) > 0 ||
304            ASN1_INTEGER_cmp(b_min, b_max) > 0)
305            goto done;
306
307        /*
308         * Calculate a_max + 1 to check for adjacency.
309         */
310        if ((bn == NULL && (bn = BN_new()) == NULL) ||
311            ASN1_INTEGER_to_BN(a_max, bn) == NULL ||
312            !BN_add_word(bn, 1)) {
313            ERR_raise(ERR_LIB_X509V3, ERR_R_MALLOC_FAILURE);
314            goto done;
315        }
316
317        if ((a_max_plus_one =
318                BN_to_ASN1_INTEGER(bn, orig = a_max_plus_one)) == NULL) {
319            a_max_plus_one = orig;
320            ERR_raise(ERR_LIB_X509V3, ERR_R_MALLOC_FAILURE);
321            goto done;
322        }
323
324        /*
325         * Punt if adjacent or overlapping.
326         */
327        if (ASN1_INTEGER_cmp(a_max_plus_one, b_min) >= 0)
328            goto done;
329    }
330
331    /*
332     * Check for inverted range.
333     */
334    i = sk_ASIdOrRange_num(choice->u.asIdsOrRanges) - 1;
335    {
336        ASIdOrRange *a = sk_ASIdOrRange_value(choice->u.asIdsOrRanges, i);
337        ASN1_INTEGER *a_min, *a_max;
338        if (a != NULL && a->type == ASIdOrRange_range) {
339            if (!extract_min_max(a, &a_min, &a_max)
340                    || ASN1_INTEGER_cmp(a_min, a_max) > 0)
341                goto done;
342        }
343    }
344
345    ret = 1;
346
347 done:
348    ASN1_INTEGER_free(a_max_plus_one);
349    BN_free(bn);
350    return ret;
351}
352
353/*
354 * Check whether an ASIdentifier extension is in canonical form.
355 */
356int X509v3_asid_is_canonical(ASIdentifiers *asid)
357{
358    return (asid == NULL ||
359            (ASIdentifierChoice_is_canonical(asid->asnum) &&
360             ASIdentifierChoice_is_canonical(asid->rdi)));
361}
362
363/*
364 * Whack an ASIdentifierChoice into canonical form.
365 */
366static int ASIdentifierChoice_canonize(ASIdentifierChoice *choice)
367{
368    ASN1_INTEGER *a_max_plus_one = NULL;
369    ASN1_INTEGER *orig;
370    BIGNUM *bn = NULL;
371    int i, ret = 0;
372
373    /*
374     * Nothing to do for empty element or inheritance.
375     */
376    if (choice == NULL || choice->type == ASIdentifierChoice_inherit)
377        return 1;
378
379    /*
380     * If not a list, or if empty list, it's broken.
381     */
382    if (choice->type != ASIdentifierChoice_asIdsOrRanges ||
383        sk_ASIdOrRange_num(choice->u.asIdsOrRanges) == 0) {
384        ERR_raise(ERR_LIB_X509V3, X509V3_R_EXTENSION_VALUE_ERROR);
385        return 0;
386    }
387
388    /*
389     * We have a non-empty list.  Sort it.
390     */
391    sk_ASIdOrRange_sort(choice->u.asIdsOrRanges);
392
393    /*
394     * Now check for errors and suboptimal encoding, rejecting the
395     * former and fixing the latter.
396     */
397    for (i = 0; i < sk_ASIdOrRange_num(choice->u.asIdsOrRanges) - 1; i++) {
398        ASIdOrRange *a = sk_ASIdOrRange_value(choice->u.asIdsOrRanges, i);
399        ASIdOrRange *b = sk_ASIdOrRange_value(choice->u.asIdsOrRanges, i + 1);
400        ASN1_INTEGER *a_min = NULL, *a_max = NULL, *b_min = NULL, *b_max =
401            NULL;
402
403        if (!extract_min_max(a, &a_min, &a_max)
404                || !extract_min_max(b, &b_min, &b_max))
405            goto done;
406
407        /*
408         * Make sure we're properly sorted (paranoia).
409         */
410        if (!ossl_assert(ASN1_INTEGER_cmp(a_min, b_min) <= 0))
411            goto done;
412
413        /*
414         * Punt inverted ranges.
415         */
416        if (ASN1_INTEGER_cmp(a_min, a_max) > 0 ||
417            ASN1_INTEGER_cmp(b_min, b_max) > 0)
418            goto done;
419
420        /*
421         * Check for overlaps.
422         */
423        if (ASN1_INTEGER_cmp(a_max, b_min) >= 0) {
424            ERR_raise(ERR_LIB_X509V3, X509V3_R_EXTENSION_VALUE_ERROR);
425            goto done;
426        }
427
428        /*
429         * Calculate a_max + 1 to check for adjacency.
430         */
431        if ((bn == NULL && (bn = BN_new()) == NULL) ||
432            ASN1_INTEGER_to_BN(a_max, bn) == NULL ||
433            !BN_add_word(bn, 1)) {
434            ERR_raise(ERR_LIB_X509V3, ERR_R_MALLOC_FAILURE);
435            goto done;
436        }
437
438        if ((a_max_plus_one =
439                 BN_to_ASN1_INTEGER(bn, orig = a_max_plus_one)) == NULL) {
440            a_max_plus_one = orig;
441            ERR_raise(ERR_LIB_X509V3, ERR_R_MALLOC_FAILURE);
442            goto done;
443        }
444
445        /*
446         * If a and b are adjacent, merge them.
447         */
448        if (ASN1_INTEGER_cmp(a_max_plus_one, b_min) == 0) {
449            ASRange *r;
450            switch (a->type) {
451            case ASIdOrRange_id:
452                if ((r = OPENSSL_malloc(sizeof(*r))) == NULL) {
453                    ERR_raise(ERR_LIB_X509V3, ERR_R_MALLOC_FAILURE);
454                    goto done;
455                }
456                r->min = a_min;
457                r->max = b_max;
458                a->type = ASIdOrRange_range;
459                a->u.range = r;
460                break;
461            case ASIdOrRange_range:
462                ASN1_INTEGER_free(a->u.range->max);
463                a->u.range->max = b_max;
464                break;
465            }
466            switch (b->type) {
467            case ASIdOrRange_id:
468                b->u.id = NULL;
469                break;
470            case ASIdOrRange_range:
471                b->u.range->max = NULL;
472                break;
473            }
474            ASIdOrRange_free(b);
475            (void)sk_ASIdOrRange_delete(choice->u.asIdsOrRanges, i + 1);
476            i--;
477            continue;
478        }
479    }
480
481    /*
482     * Check for final inverted range.
483     */
484    i = sk_ASIdOrRange_num(choice->u.asIdsOrRanges) - 1;
485    {
486        ASIdOrRange *a = sk_ASIdOrRange_value(choice->u.asIdsOrRanges, i);
487        ASN1_INTEGER *a_min, *a_max;
488        if (a != NULL && a->type == ASIdOrRange_range) {
489            if (!extract_min_max(a, &a_min, &a_max)
490                    || ASN1_INTEGER_cmp(a_min, a_max) > 0)
491                goto done;
492        }
493    }
494
495    /* Paranoia */
496    if (!ossl_assert(ASIdentifierChoice_is_canonical(choice)))
497        goto done;
498
499    ret = 1;
500
501 done:
502    ASN1_INTEGER_free(a_max_plus_one);
503    BN_free(bn);
504    return ret;
505}
506
507/*
508 * Whack an ASIdentifier extension into canonical form.
509 */
510int X509v3_asid_canonize(ASIdentifiers *asid)
511{
512    return (asid == NULL ||
513            (ASIdentifierChoice_canonize(asid->asnum) &&
514             ASIdentifierChoice_canonize(asid->rdi)));
515}
516
517/*
518 * v2i method for an ASIdentifier extension.
519 */
520static void *v2i_ASIdentifiers(const struct v3_ext_method *method,
521                               struct v3_ext_ctx *ctx,
522                               STACK_OF(CONF_VALUE) *values)
523{
524    ASN1_INTEGER *min = NULL, *max = NULL;
525    ASIdentifiers *asid = NULL;
526    int i;
527
528    if ((asid = ASIdentifiers_new()) == NULL) {
529        ERR_raise(ERR_LIB_X509V3, ERR_R_MALLOC_FAILURE);
530        return NULL;
531    }
532
533    for (i = 0; i < sk_CONF_VALUE_num(values); i++) {
534        CONF_VALUE *val = sk_CONF_VALUE_value(values, i);
535        int i1 = 0, i2 = 0, i3 = 0, is_range = 0, which = 0;
536
537        /*
538         * Figure out whether this is an AS or an RDI.
539         */
540        if (!ossl_v3_name_cmp(val->name, "AS")) {
541            which = V3_ASID_ASNUM;
542        } else if (!ossl_v3_name_cmp(val->name, "RDI")) {
543            which = V3_ASID_RDI;
544        } else {
545            ERR_raise(ERR_LIB_X509V3, X509V3_R_EXTENSION_NAME_ERROR);
546            X509V3_conf_add_error_name_value(val);
547            goto err;
548        }
549
550        if (val->value == NULL) {
551            ERR_raise(ERR_LIB_X509V3, X509V3_R_EXTENSION_VALUE_ERROR);
552            goto err;
553        }
554
555        /*
556         * Handle inheritance.
557         */
558        if (strcmp(val->value, "inherit") == 0) {
559            if (X509v3_asid_add_inherit(asid, which))
560                continue;
561            ERR_raise(ERR_LIB_X509V3, X509V3_R_INVALID_INHERITANCE);
562            X509V3_conf_add_error_name_value(val);
563            goto err;
564        }
565
566        /*
567         * Number, range, or mistake, pick it apart and figure out which.
568         */
569        i1 = strspn(val->value, "0123456789");
570        if (val->value[i1] == '\0') {
571            is_range = 0;
572        } else {
573            is_range = 1;
574            i2 = i1 + strspn(val->value + i1, " \t");
575            if (val->value[i2] != '-') {
576                ERR_raise(ERR_LIB_X509V3, X509V3_R_INVALID_ASNUMBER);
577                X509V3_conf_add_error_name_value(val);
578                goto err;
579            }
580            i2++;
581            i2 = i2 + strspn(val->value + i2, " \t");
582            i3 = i2 + strspn(val->value + i2, "0123456789");
583            if (val->value[i3] != '\0') {
584                ERR_raise(ERR_LIB_X509V3, X509V3_R_INVALID_ASRANGE);
585                X509V3_conf_add_error_name_value(val);
586                goto err;
587            }
588        }
589
590        /*
591         * Syntax is ok, read and add it.
592         */
593        if (!is_range) {
594            if (!X509V3_get_value_int(val, &min)) {
595                ERR_raise(ERR_LIB_X509V3, ERR_R_MALLOC_FAILURE);
596                goto err;
597            }
598        } else {
599            char *s = OPENSSL_strdup(val->value);
600            if (s == NULL) {
601                ERR_raise(ERR_LIB_X509V3, ERR_R_MALLOC_FAILURE);
602                goto err;
603            }
604            s[i1] = '\0';
605            min = s2i_ASN1_INTEGER(NULL, s);
606            max = s2i_ASN1_INTEGER(NULL, s + i2);
607            OPENSSL_free(s);
608            if (min == NULL || max == NULL) {
609                ERR_raise(ERR_LIB_X509V3, ERR_R_MALLOC_FAILURE);
610                goto err;
611            }
612            if (ASN1_INTEGER_cmp(min, max) > 0) {
613                ERR_raise(ERR_LIB_X509V3, X509V3_R_EXTENSION_VALUE_ERROR);
614                goto err;
615            }
616        }
617        if (!X509v3_asid_add_id_or_range(asid, which, min, max)) {
618            ERR_raise(ERR_LIB_X509V3, ERR_R_MALLOC_FAILURE);
619            goto err;
620        }
621        min = max = NULL;
622    }
623
624    /*
625     * Canonize the result, then we're done.
626     */
627    if (!X509v3_asid_canonize(asid))
628        goto err;
629    return asid;
630
631 err:
632    ASIdentifiers_free(asid);
633    ASN1_INTEGER_free(min);
634    ASN1_INTEGER_free(max);
635    return NULL;
636}
637
638/*
639 * OpenSSL dispatch.
640 */
641const X509V3_EXT_METHOD ossl_v3_asid = {
642    NID_sbgp_autonomousSysNum,  /* nid */
643    0,                          /* flags */
644    ASN1_ITEM_ref(ASIdentifiers), /* template */
645    0, 0, 0, 0,                 /* old functions, ignored */
646    0,                          /* i2s */
647    0,                          /* s2i */
648    0,                          /* i2v */
649    v2i_ASIdentifiers,          /* v2i */
650    i2r_ASIdentifiers,          /* i2r */
651    0,                          /* r2i */
652    NULL                        /* extension-specific data */
653};
654
655/*
656 * Figure out whether extension uses inheritance.
657 */
658int X509v3_asid_inherits(ASIdentifiers *asid)
659{
660    return (asid != NULL &&
661            ((asid->asnum != NULL &&
662              asid->asnum->type == ASIdentifierChoice_inherit) ||
663             (asid->rdi != NULL &&
664              asid->rdi->type == ASIdentifierChoice_inherit)));
665}
666
667/*
668 * Figure out whether parent contains child.
669 */
670static int asid_contains(ASIdOrRanges *parent, ASIdOrRanges *child)
671{
672    ASN1_INTEGER *p_min = NULL, *p_max = NULL, *c_min = NULL, *c_max = NULL;
673    int p, c;
674
675    if (child == NULL || parent == child)
676        return 1;
677    if (parent == NULL)
678        return 0;
679
680    p = 0;
681    for (c = 0; c < sk_ASIdOrRange_num(child); c++) {
682        if (!extract_min_max(sk_ASIdOrRange_value(child, c), &c_min, &c_max))
683            return 0;
684        for (;; p++) {
685            if (p >= sk_ASIdOrRange_num(parent))
686                return 0;
687            if (!extract_min_max(sk_ASIdOrRange_value(parent, p), &p_min,
688                                 &p_max))
689                return 0;
690            if (ASN1_INTEGER_cmp(p_max, c_max) < 0)
691                continue;
692            if (ASN1_INTEGER_cmp(p_min, c_min) > 0)
693                return 0;
694            break;
695        }
696    }
697
698    return 1;
699}
700
701/*
702 * Test whether a is a subset of b.
703 */
704int X509v3_asid_subset(ASIdentifiers *a, ASIdentifiers *b)
705{
706    int subset;
707
708    if (a == NULL || a == b)
709        return 1;
710
711    if (b == NULL)
712        return 0;
713
714    if (X509v3_asid_inherits(a) || X509v3_asid_inherits(b))
715        return 0;
716
717    subset = a->asnum == NULL
718             || (b->asnum != NULL
719                 && asid_contains(b->asnum->u.asIdsOrRanges,
720                                  a->asnum->u.asIdsOrRanges));
721    if (!subset)
722        return 0;
723
724    return a->rdi == NULL
725           || (b->rdi != NULL
726               && asid_contains(b->rdi->u.asIdsOrRanges,
727                                a->rdi->u.asIdsOrRanges));
728}
729
730/*
731 * Validation error handling via callback.
732 */
733#define validation_err(_err_)           \
734  do {                                  \
735    if (ctx != NULL) {                  \
736      ctx->error = _err_;               \
737      ctx->error_depth = i;             \
738      ctx->current_cert = x;            \
739      ret = ctx->verify_cb(0, ctx);     \
740    } else {                            \
741      ret = 0;                          \
742    }                                   \
743    if (!ret)                           \
744      goto done;                        \
745  } while (0)
746
747/*
748 * Core code for RFC 3779 3.3 path validation.
749 */
750static int asid_validate_path_internal(X509_STORE_CTX *ctx,
751                                       STACK_OF(X509) *chain,
752                                       ASIdentifiers *ext)
753{
754    ASIdOrRanges *child_as = NULL, *child_rdi = NULL;
755    int i, ret = 1, inherit_as = 0, inherit_rdi = 0;
756    X509 *x;
757
758    if (!ossl_assert(chain != NULL && sk_X509_num(chain) > 0)
759            || !ossl_assert(ctx != NULL || ext != NULL)
760            || !ossl_assert(ctx == NULL || ctx->verify_cb != NULL)) {
761        if (ctx != NULL)
762            ctx->error = X509_V_ERR_UNSPECIFIED;
763        return 0;
764    }
765
766
767    /*
768     * Figure out where to start.  If we don't have an extension to
769     * check, we're done.  Otherwise, check canonical form and
770     * set up for walking up the chain.
771     */
772    if (ext != NULL) {
773        i = -1;
774        x = NULL;
775    } else {
776        i = 0;
777        x = sk_X509_value(chain, i);
778        if ((ext = x->rfc3779_asid) == NULL)
779            goto done;
780    }
781    if (!X509v3_asid_is_canonical(ext))
782        validation_err(X509_V_ERR_INVALID_EXTENSION);
783    if (ext->asnum != NULL) {
784        switch (ext->asnum->type) {
785        case ASIdentifierChoice_inherit:
786            inherit_as = 1;
787            break;
788        case ASIdentifierChoice_asIdsOrRanges:
789            child_as = ext->asnum->u.asIdsOrRanges;
790            break;
791        }
792    }
793    if (ext->rdi != NULL) {
794        switch (ext->rdi->type) {
795        case ASIdentifierChoice_inherit:
796            inherit_rdi = 1;
797            break;
798        case ASIdentifierChoice_asIdsOrRanges:
799            child_rdi = ext->rdi->u.asIdsOrRanges;
800            break;
801        }
802    }
803
804    /*
805     * Now walk up the chain.  Extensions must be in canonical form, no
806     * cert may list resources that its parent doesn't list.
807     */
808    for (i++; i < sk_X509_num(chain); i++) {
809        x = sk_X509_value(chain, i);
810        if (!ossl_assert(x != NULL)) {
811            if (ctx != NULL)
812                ctx->error = X509_V_ERR_UNSPECIFIED;
813            return 0;
814        }
815        if (x->rfc3779_asid == NULL) {
816            if (child_as != NULL || child_rdi != NULL)
817                validation_err(X509_V_ERR_UNNESTED_RESOURCE);
818            continue;
819        }
820        if (!X509v3_asid_is_canonical(x->rfc3779_asid))
821            validation_err(X509_V_ERR_INVALID_EXTENSION);
822        if (x->rfc3779_asid->asnum == NULL && child_as != NULL) {
823            validation_err(X509_V_ERR_UNNESTED_RESOURCE);
824            child_as = NULL;
825            inherit_as = 0;
826        }
827        if (x->rfc3779_asid->asnum != NULL &&
828            x->rfc3779_asid->asnum->type ==
829            ASIdentifierChoice_asIdsOrRanges) {
830            if (inherit_as
831                || asid_contains(x->rfc3779_asid->asnum->u.asIdsOrRanges,
832                                 child_as)) {
833                child_as = x->rfc3779_asid->asnum->u.asIdsOrRanges;
834                inherit_as = 0;
835            } else {
836                validation_err(X509_V_ERR_UNNESTED_RESOURCE);
837            }
838        }
839        if (x->rfc3779_asid->rdi == NULL && child_rdi != NULL) {
840            validation_err(X509_V_ERR_UNNESTED_RESOURCE);
841            child_rdi = NULL;
842            inherit_rdi = 0;
843        }
844        if (x->rfc3779_asid->rdi != NULL &&
845            x->rfc3779_asid->rdi->type == ASIdentifierChoice_asIdsOrRanges) {
846            if (inherit_rdi ||
847                asid_contains(x->rfc3779_asid->rdi->u.asIdsOrRanges,
848                              child_rdi)) {
849                child_rdi = x->rfc3779_asid->rdi->u.asIdsOrRanges;
850                inherit_rdi = 0;
851            } else {
852                validation_err(X509_V_ERR_UNNESTED_RESOURCE);
853            }
854        }
855    }
856
857    /*
858     * Trust anchor can't inherit.
859     */
860    if (!ossl_assert(x != NULL)) {
861        if (ctx != NULL)
862            ctx->error = X509_V_ERR_UNSPECIFIED;
863        return 0;
864    }
865    if (x->rfc3779_asid != NULL) {
866        if (x->rfc3779_asid->asnum != NULL &&
867            x->rfc3779_asid->asnum->type == ASIdentifierChoice_inherit)
868            validation_err(X509_V_ERR_UNNESTED_RESOURCE);
869        if (x->rfc3779_asid->rdi != NULL &&
870            x->rfc3779_asid->rdi->type == ASIdentifierChoice_inherit)
871            validation_err(X509_V_ERR_UNNESTED_RESOURCE);
872    }
873
874 done:
875    return ret;
876}
877
878#undef validation_err
879
880/*
881 * RFC 3779 3.3 path validation -- called from X509_verify_cert().
882 */
883int X509v3_asid_validate_path(X509_STORE_CTX *ctx)
884{
885    if (ctx->chain == NULL
886            || sk_X509_num(ctx->chain) == 0
887            || ctx->verify_cb == NULL) {
888        ctx->error = X509_V_ERR_UNSPECIFIED;
889        return 0;
890    }
891    return asid_validate_path_internal(ctx, ctx->chain, NULL);
892}
893
894/*
895 * RFC 3779 3.3 path validation of an extension.
896 * Test whether chain covers extension.
897 */
898int X509v3_asid_validate_resource_set(STACK_OF(X509) *chain,
899                                      ASIdentifiers *ext, int allow_inheritance)
900{
901    if (ext == NULL)
902        return 1;
903    if (chain == NULL || sk_X509_num(chain) == 0)
904        return 0;
905    if (!allow_inheritance && X509v3_asid_inherits(ext))
906        return 0;
907    return asid_validate_path_internal(NULL, chain, ext);
908}
909
910#endif                          /* OPENSSL_NO_RFC3779 */
911