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diff --git a/src/lib/libcrypto/x509/x509_purp.c b/src/lib/libcrypto/x509/x509_purp.c
new file mode 100644
index 0000000000..62b3bcfe3a
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1/* $OpenBSD: x509_purp.c,v 1.1 2020/06/04 15:19:32 jsing Exp $ */
2/* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
3 * project 2001.
4 */
5/* ====================================================================
6 * Copyright (c) 1999-2004 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 <stdio.h>
60#include <string.h>
61
62#include <openssl/opensslconf.h>
63
64#include <openssl/err.h>
65#include <openssl/x509v3.h>
66#include <openssl/x509_vfy.h>
67
68#define V1_ROOT (EXFLAG_V1|EXFLAG_SS)
69#define ku_reject(x, usage) \
70 (((x)->ex_flags & EXFLAG_KUSAGE) && !((x)->ex_kusage & (usage)))
71#define xku_reject(x, usage) \
72 (((x)->ex_flags & EXFLAG_XKUSAGE) && !((x)->ex_xkusage & (usage)))
73#define ns_reject(x, usage) \
74 (((x)->ex_flags & EXFLAG_NSCERT) && !((x)->ex_nscert & (usage)))
75
76static void x509v3_cache_extensions(X509 *x);
77
78static int check_ssl_ca(const X509 *x);
79static int check_purpose_ssl_client(const X509_PURPOSE *xp, const X509 *x,
80 int ca);
81static int check_purpose_ssl_server(const X509_PURPOSE *xp, const X509 *x,
82 int ca);
83static int check_purpose_ns_ssl_server(const X509_PURPOSE *xp, const X509 *x,
84 int ca);
85static int purpose_smime(const X509 *x, int ca);
86static int check_purpose_smime_sign(const X509_PURPOSE *xp, const X509 *x,
87 int ca);
88static int check_purpose_smime_encrypt(const X509_PURPOSE *xp, const X509 *x,
89 int ca);
90static int check_purpose_crl_sign(const X509_PURPOSE *xp, const X509 *x,
91 int ca);
92static int check_purpose_timestamp_sign(const X509_PURPOSE *xp, const X509 *x,
93 int ca);
94static int no_check(const X509_PURPOSE *xp, const X509 *x, int ca);
95static int ocsp_helper(const X509_PURPOSE *xp, const X509 *x, int ca);
96
97static int xp_cmp(const X509_PURPOSE * const *a, const X509_PURPOSE * const *b);
98static void xptable_free(X509_PURPOSE *p);
99
100static X509_PURPOSE xstandard[] = {
101 {X509_PURPOSE_SSL_CLIENT, X509_TRUST_SSL_CLIENT, 0, check_purpose_ssl_client, "SSL client", "sslclient", NULL},
102 {X509_PURPOSE_SSL_SERVER, X509_TRUST_SSL_SERVER, 0, check_purpose_ssl_server, "SSL server", "sslserver", NULL},
103 {X509_PURPOSE_NS_SSL_SERVER, X509_TRUST_SSL_SERVER, 0, check_purpose_ns_ssl_server, "Netscape SSL server", "nssslserver", NULL},
104 {X509_PURPOSE_SMIME_SIGN, X509_TRUST_EMAIL, 0, check_purpose_smime_sign, "S/MIME signing", "smimesign", NULL},
105 {X509_PURPOSE_SMIME_ENCRYPT, X509_TRUST_EMAIL, 0, check_purpose_smime_encrypt, "S/MIME encryption", "smimeencrypt", NULL},
106 {X509_PURPOSE_CRL_SIGN, X509_TRUST_COMPAT, 0, check_purpose_crl_sign, "CRL signing", "crlsign", NULL},
107 {X509_PURPOSE_ANY, X509_TRUST_DEFAULT, 0, no_check, "Any Purpose", "any", NULL},
108 {X509_PURPOSE_OCSP_HELPER, X509_TRUST_COMPAT, 0, ocsp_helper, "OCSP helper", "ocsphelper", NULL},
109 {X509_PURPOSE_TIMESTAMP_SIGN, X509_TRUST_TSA, 0, check_purpose_timestamp_sign, "Time Stamp signing", "timestampsign", NULL},
110};
111
112#define X509_PURPOSE_COUNT (sizeof(xstandard)/sizeof(X509_PURPOSE))
113
114static STACK_OF(X509_PURPOSE) *xptable = NULL;
115
116static int
117xp_cmp(const X509_PURPOSE * const *a, const X509_PURPOSE * const *b)
118{
119 return (*a)->purpose - (*b)->purpose;
120}
121
122/* As much as I'd like to make X509_check_purpose use a "const" X509*
123 * I really can't because it does recalculate hashes and do other non-const
124 * things. */
125int
126X509_check_purpose(X509 *x, int id, int ca)
127{
128 int idx;
129 const X509_PURPOSE *pt;
130
131 if (!(x->ex_flags & EXFLAG_SET)) {
132 CRYPTO_w_lock(CRYPTO_LOCK_X509);
133 x509v3_cache_extensions(x);
134 CRYPTO_w_unlock(CRYPTO_LOCK_X509);
135 }
136 if (id == -1)
137 return 1;
138 idx = X509_PURPOSE_get_by_id(id);
139 if (idx == -1)
140 return -1;
141 pt = X509_PURPOSE_get0(idx);
142 return pt->check_purpose(pt, x, ca);
143}
144
145int
146X509_PURPOSE_set(int *p, int purpose)
147{
148 if (X509_PURPOSE_get_by_id(purpose) == -1) {
149 X509V3error(X509V3_R_INVALID_PURPOSE);
150 return 0;
151 }
152 *p = purpose;
153 return 1;
154}
155
156int
157X509_PURPOSE_get_count(void)
158{
159 if (!xptable)
160 return X509_PURPOSE_COUNT;
161 return sk_X509_PURPOSE_num(xptable) + X509_PURPOSE_COUNT;
162}
163
164X509_PURPOSE *
165X509_PURPOSE_get0(int idx)
166{
167 if (idx < 0)
168 return NULL;
169 if (idx < (int)X509_PURPOSE_COUNT)
170 return xstandard + idx;
171 return sk_X509_PURPOSE_value(xptable, idx - X509_PURPOSE_COUNT);
172}
173
174int
175X509_PURPOSE_get_by_sname(const char *sname)
176{
177 int i;
178 X509_PURPOSE *xptmp;
179
180 for (i = 0; i < X509_PURPOSE_get_count(); i++) {
181 xptmp = X509_PURPOSE_get0(i);
182 if (!strcmp(xptmp->sname, sname))
183 return i;
184 }
185 return -1;
186}
187
188int
189X509_PURPOSE_get_by_id(int purpose)
190{
191 X509_PURPOSE tmp;
192 int idx;
193
194 if ((purpose >= X509_PURPOSE_MIN) && (purpose <= X509_PURPOSE_MAX))
195 return purpose - X509_PURPOSE_MIN;
196 tmp.purpose = purpose;
197 if (!xptable)
198 return -1;
199 idx = sk_X509_PURPOSE_find(xptable, &tmp);
200 if (idx == -1)
201 return -1;
202 return idx + X509_PURPOSE_COUNT;
203}
204
205int
206X509_PURPOSE_add(int id, int trust, int flags,
207 int (*ck)(const X509_PURPOSE *, const X509 *, int), const char *name,
208 const char *sname, void *arg)
209{
210 int idx;
211 X509_PURPOSE *ptmp;
212 char *name_dup, *sname_dup;
213
214 name_dup = sname_dup = NULL;
215
216 if (name == NULL || sname == NULL) {
217 X509V3error(X509V3_R_INVALID_NULL_ARGUMENT);
218 return 0;
219 }
220
221 /* This is set according to what we change: application can't set it */
222 flags &= ~X509_PURPOSE_DYNAMIC;
223 /* This will always be set for application modified trust entries */
224 flags |= X509_PURPOSE_DYNAMIC_NAME;
225 /* Get existing entry if any */
226 idx = X509_PURPOSE_get_by_id(id);
227 /* Need a new entry */
228 if (idx == -1) {
229 if ((ptmp = malloc(sizeof(X509_PURPOSE))) == NULL) {
230 X509V3error(ERR_R_MALLOC_FAILURE);
231 return 0;
232 }
233 ptmp->flags = X509_PURPOSE_DYNAMIC;
234 } else
235 ptmp = X509_PURPOSE_get0(idx);
236
237 if ((name_dup = strdup(name)) == NULL)
238 goto err;
239 if ((sname_dup = strdup(sname)) == NULL)
240 goto err;
241
242 /* free existing name if dynamic */
243 if (ptmp->flags & X509_PURPOSE_DYNAMIC_NAME) {
244 free(ptmp->name);
245 free(ptmp->sname);
246 }
247 /* dup supplied name */
248 ptmp->name = name_dup;
249 ptmp->sname = sname_dup;
250 /* Keep the dynamic flag of existing entry */
251 ptmp->flags &= X509_PURPOSE_DYNAMIC;
252 /* Set all other flags */
253 ptmp->flags |= flags;
254
255 ptmp->purpose = id;
256 ptmp->trust = trust;
257 ptmp->check_purpose = ck;
258 ptmp->usr_data = arg;
259
260 /* If its a new entry manage the dynamic table */
261 if (idx == -1) {
262 if (xptable == NULL &&
263 (xptable = sk_X509_PURPOSE_new(xp_cmp)) == NULL)
264 goto err;
265 if (sk_X509_PURPOSE_push(xptable, ptmp) == 0)
266 goto err;
267 }
268 return 1;
269
270err:
271 free(name_dup);
272 free(sname_dup);
273 if (idx == -1)
274 free(ptmp);
275 X509V3error(ERR_R_MALLOC_FAILURE);
276 return 0;
277}
278
279static void
280xptable_free(X509_PURPOSE *p)
281{
282 if (!p)
283 return;
284 if (p->flags & X509_PURPOSE_DYNAMIC) {
285 if (p->flags & X509_PURPOSE_DYNAMIC_NAME) {
286 free(p->name);
287 free(p->sname);
288 }
289 free(p);
290 }
291}
292
293void
294X509_PURPOSE_cleanup(void)
295{
296 unsigned int i;
297
298 sk_X509_PURPOSE_pop_free(xptable, xptable_free);
299 for(i = 0; i < X509_PURPOSE_COUNT; i++)
300 xptable_free(xstandard + i);
301 xptable = NULL;
302}
303
304int
305X509_PURPOSE_get_id(const X509_PURPOSE *xp)
306{
307 return xp->purpose;
308}
309
310char *
311X509_PURPOSE_get0_name(const X509_PURPOSE *xp)
312{
313 return xp->name;
314}
315
316char *
317X509_PURPOSE_get0_sname(const X509_PURPOSE *xp)
318{
319 return xp->sname;
320}
321
322int
323X509_PURPOSE_get_trust(const X509_PURPOSE *xp)
324{
325 return xp->trust;
326}
327
328static int
329nid_cmp(const int *a, const int *b)
330{
331 return *a - *b;
332}
333
334static int nid_cmp_BSEARCH_CMP_FN(const void *, const void *);
335static int nid_cmp(int const *, int const *);
336static int *OBJ_bsearch_nid(int *key, int const *base, int num);
337
338static int
339nid_cmp_BSEARCH_CMP_FN(const void *a_, const void *b_)
340{
341 int const *a = a_;
342 int const *b = b_;
343 return nid_cmp(a, b);
344}
345
346static int *
347OBJ_bsearch_nid(int *key, int const *base, int num)
348{
349 return (int *)OBJ_bsearch_(key, base, num, sizeof(int),
350 nid_cmp_BSEARCH_CMP_FN);
351}
352
353int
354X509_supported_extension(X509_EXTENSION *ex)
355{
356 /* This table is a list of the NIDs of supported extensions:
357 * that is those which are used by the verify process. If
358 * an extension is critical and doesn't appear in this list
359 * then the verify process will normally reject the certificate.
360 * The list must be kept in numerical order because it will be
361 * searched using bsearch.
362 */
363
364 static const int supported_nids[] = {
365 NID_netscape_cert_type, /* 71 */
366 NID_key_usage, /* 83 */
367 NID_subject_alt_name, /* 85 */
368 NID_basic_constraints, /* 87 */
369 NID_certificate_policies, /* 89 */
370 NID_ext_key_usage, /* 126 */
371 NID_policy_constraints, /* 401 */
372 NID_proxyCertInfo, /* 663 */
373 NID_name_constraints, /* 666 */
374 NID_policy_mappings, /* 747 */
375 NID_inhibit_any_policy /* 748 */
376 };
377
378 int ex_nid = OBJ_obj2nid(X509_EXTENSION_get_object(ex));
379
380 if (ex_nid == NID_undef)
381 return 0;
382
383 if (OBJ_bsearch_nid(&ex_nid, supported_nids,
384 sizeof(supported_nids) / sizeof(int)))
385 return 1;
386 return 0;
387}
388
389static void
390setup_dp(X509 *x, DIST_POINT *dp)
391{
392 X509_NAME *iname = NULL;
393 int i;
394
395 if (dp->reasons) {
396 if (dp->reasons->length > 0)
397 dp->dp_reasons = dp->reasons->data[0];
398 if (dp->reasons->length > 1)
399 dp->dp_reasons |= (dp->reasons->data[1] << 8);
400 dp->dp_reasons &= CRLDP_ALL_REASONS;
401 } else
402 dp->dp_reasons = CRLDP_ALL_REASONS;
403 if (!dp->distpoint || (dp->distpoint->type != 1))
404 return;
405 for (i = 0; i < sk_GENERAL_NAME_num(dp->CRLissuer); i++) {
406 GENERAL_NAME *gen = sk_GENERAL_NAME_value(dp->CRLissuer, i);
407 if (gen->type == GEN_DIRNAME) {
408 iname = gen->d.directoryName;
409 break;
410 }
411 }
412 if (!iname)
413 iname = X509_get_issuer_name(x);
414
415 DIST_POINT_set_dpname(dp->distpoint, iname);
416
417}
418
419static void
420setup_crldp(X509 *x)
421{
422 int i;
423
424 x->crldp = X509_get_ext_d2i(x, NID_crl_distribution_points, NULL, NULL);
425 for (i = 0; i < sk_DIST_POINT_num(x->crldp); i++)
426 setup_dp(x, sk_DIST_POINT_value(x->crldp, i));
427}
428
429static void
430x509v3_cache_extensions(X509 *x)
431{
432 BASIC_CONSTRAINTS *bs;
433 PROXY_CERT_INFO_EXTENSION *pci;
434 ASN1_BIT_STRING *usage;
435 ASN1_BIT_STRING *ns;
436 EXTENDED_KEY_USAGE *extusage;
437 X509_EXTENSION *ex;
438 int i;
439
440 if (x->ex_flags & EXFLAG_SET)
441 return;
442
443#ifndef OPENSSL_NO_SHA
444 X509_digest(x, EVP_sha1(), x->sha1_hash, NULL);
445#endif
446
447 /* V1 should mean no extensions ... */
448 if (!X509_get_version(x))
449 x->ex_flags |= EXFLAG_V1;
450
451 /* Handle basic constraints */
452 if ((bs = X509_get_ext_d2i(x, NID_basic_constraints, NULL, NULL))) {
453 if (bs->ca)
454 x->ex_flags |= EXFLAG_CA;
455 if (bs->pathlen) {
456 if ((bs->pathlen->type == V_ASN1_NEG_INTEGER) ||
457 !bs->ca) {
458 x->ex_flags |= EXFLAG_INVALID;
459 x->ex_pathlen = 0;
460 } else
461 x->ex_pathlen = ASN1_INTEGER_get(bs->pathlen);
462 } else
463 x->ex_pathlen = -1;
464 BASIC_CONSTRAINTS_free(bs);
465 x->ex_flags |= EXFLAG_BCONS;
466 }
467
468 /* Handle proxy certificates */
469 if ((pci = X509_get_ext_d2i(x, NID_proxyCertInfo, NULL, NULL))) {
470 if (x->ex_flags & EXFLAG_CA ||
471 X509_get_ext_by_NID(x, NID_subject_alt_name, -1) >= 0 ||
472 X509_get_ext_by_NID(x, NID_issuer_alt_name, -1) >= 0) {
473 x->ex_flags |= EXFLAG_INVALID;
474 }
475 if (pci->pcPathLengthConstraint) {
476 if (pci->pcPathLengthConstraint->type ==
477 V_ASN1_NEG_INTEGER) {
478 x->ex_flags |= EXFLAG_INVALID;
479 x->ex_pcpathlen = 0;
480 } else
481 x->ex_pcpathlen =
482 ASN1_INTEGER_get(pci->
483 pcPathLengthConstraint);
484 } else
485 x->ex_pcpathlen = -1;
486 PROXY_CERT_INFO_EXTENSION_free(pci);
487 x->ex_flags |= EXFLAG_PROXY;
488 }
489
490 /* Handle key usage */
491 if ((usage = X509_get_ext_d2i(x, NID_key_usage, NULL, NULL))) {
492 if (usage->length > 0) {
493 x->ex_kusage = usage->data[0];
494 if (usage->length > 1)
495 x->ex_kusage |= usage->data[1] << 8;
496 } else
497 x->ex_kusage = 0;
498 x->ex_flags |= EXFLAG_KUSAGE;
499 ASN1_BIT_STRING_free(usage);
500 }
501 x->ex_xkusage = 0;
502 if ((extusage = X509_get_ext_d2i(x, NID_ext_key_usage, NULL, NULL))) {
503 x->ex_flags |= EXFLAG_XKUSAGE;
504 for (i = 0; i < sk_ASN1_OBJECT_num(extusage); i++) {
505 switch (OBJ_obj2nid(sk_ASN1_OBJECT_value(extusage, i))) {
506 case NID_server_auth:
507 x->ex_xkusage |= XKU_SSL_SERVER;
508 break;
509
510 case NID_client_auth:
511 x->ex_xkusage |= XKU_SSL_CLIENT;
512 break;
513
514 case NID_email_protect:
515 x->ex_xkusage |= XKU_SMIME;
516 break;
517
518 case NID_code_sign:
519 x->ex_xkusage |= XKU_CODE_SIGN;
520 break;
521
522 case NID_ms_sgc:
523 case NID_ns_sgc:
524 x->ex_xkusage |= XKU_SGC;
525 break;
526
527 case NID_OCSP_sign:
528 x->ex_xkusage |= XKU_OCSP_SIGN;
529 break;
530
531 case NID_time_stamp:
532 x->ex_xkusage |= XKU_TIMESTAMP;
533 break;
534
535 case NID_dvcs:
536 x->ex_xkusage |= XKU_DVCS;
537 break;
538 }
539 }
540 sk_ASN1_OBJECT_pop_free(extusage, ASN1_OBJECT_free);
541 }
542
543 if ((ns = X509_get_ext_d2i(x, NID_netscape_cert_type, NULL, NULL))) {
544 if (ns->length > 0)
545 x->ex_nscert = ns->data[0];
546 else
547 x->ex_nscert = 0;
548 x->ex_flags |= EXFLAG_NSCERT;
549 ASN1_BIT_STRING_free(ns);
550 }
551
552 x->skid = X509_get_ext_d2i(x, NID_subject_key_identifier, NULL, NULL);
553 x->akid = X509_get_ext_d2i(x, NID_authority_key_identifier, NULL, NULL);
554
555 /* Does subject name match issuer? */
556 if (!X509_NAME_cmp(X509_get_subject_name(x), X509_get_issuer_name(x))) {
557 x->ex_flags |= EXFLAG_SI;
558 /* If SKID matches AKID also indicate self signed. */
559 if (X509_check_akid(x, x->akid) == X509_V_OK &&
560 !ku_reject(x, KU_KEY_CERT_SIGN))
561 x->ex_flags |= EXFLAG_SS;
562 }
563
564 x->altname = X509_get_ext_d2i(x, NID_subject_alt_name, NULL, NULL);
565 x->nc = X509_get_ext_d2i(x, NID_name_constraints, &i, NULL);
566 if (!x->nc && (i != -1))
567 x->ex_flags |= EXFLAG_INVALID;
568 setup_crldp(x);
569
570 for (i = 0; i < X509_get_ext_count(x); i++) {
571 ex = X509_get_ext(x, i);
572 if (OBJ_obj2nid(X509_EXTENSION_get_object(ex)) ==
573 NID_freshest_crl)
574 x->ex_flags |= EXFLAG_FRESHEST;
575 if (!X509_EXTENSION_get_critical(ex))
576 continue;
577 if (!X509_supported_extension(ex)) {
578 x->ex_flags |= EXFLAG_CRITICAL;
579 break;
580 }
581 }
582 x->ex_flags |= EXFLAG_SET;
583}
584
585/* CA checks common to all purposes
586 * return codes:
587 * 0 not a CA
588 * 1 is a CA
589 * 2 basicConstraints absent so "maybe" a CA
590 * 3 basicConstraints absent but self signed V1.
591 * 4 basicConstraints absent but keyUsage present and keyCertSign asserted.
592 */
593
594static int
595check_ca(const X509 *x)
596{
597 /* keyUsage if present should allow cert signing */
598 if (ku_reject(x, KU_KEY_CERT_SIGN))
599 return 0;
600 if (x->ex_flags & EXFLAG_BCONS) {
601 if (x->ex_flags & EXFLAG_CA)
602 return 1;
603 /* If basicConstraints says not a CA then say so */
604 else
605 return 0;
606 } else {
607 /* we support V1 roots for... uh, I don't really know why. */
608 if ((x->ex_flags & V1_ROOT) == V1_ROOT)
609 return 3;
610 /* If key usage present it must have certSign so tolerate it */
611 else if (x->ex_flags & EXFLAG_KUSAGE)
612 return 4;
613 /* Older certificates could have Netscape-specific CA types */
614 else if (x->ex_flags & EXFLAG_NSCERT &&
615 x->ex_nscert & NS_ANY_CA)
616 return 5;
617 /* can this still be regarded a CA certificate? I doubt it */
618 return 0;
619 }
620}
621
622int
623X509_check_ca(X509 *x)
624{
625 if (!(x->ex_flags & EXFLAG_SET)) {
626 CRYPTO_w_lock(CRYPTO_LOCK_X509);
627 x509v3_cache_extensions(x);
628 CRYPTO_w_unlock(CRYPTO_LOCK_X509);
629 }
630
631 return check_ca(x);
632}
633
634/* Check SSL CA: common checks for SSL client and server */
635static int
636check_ssl_ca(const X509 *x)
637{
638 int ca_ret;
639
640 ca_ret = check_ca(x);
641 if (!ca_ret)
642 return 0;
643 /* check nsCertType if present */
644 if (ca_ret != 5 || x->ex_nscert & NS_SSL_CA)
645 return ca_ret;
646 else
647 return 0;
648}
649
650static int
651check_purpose_ssl_client(const X509_PURPOSE *xp, const X509 *x, int ca)
652{
653 if (xku_reject(x, XKU_SSL_CLIENT))
654 return 0;
655 if (ca)
656 return check_ssl_ca(x);
657 /* We need to do digital signatures with it */
658 if (ku_reject(x, KU_DIGITAL_SIGNATURE))
659 return 0;
660 /* nsCertType if present should allow SSL client use */
661 if (ns_reject(x, NS_SSL_CLIENT))
662 return 0;
663 return 1;
664}
665
666static int
667check_purpose_ssl_server(const X509_PURPOSE *xp, const X509 *x, int ca)
668{
669 if (xku_reject(x, XKU_SSL_SERVER|XKU_SGC))
670 return 0;
671 if (ca)
672 return check_ssl_ca(x);
673
674 if (ns_reject(x, NS_SSL_SERVER))
675 return 0;
676 /* Now as for keyUsage: we'll at least need to sign OR encipher */
677 if (ku_reject(x, KU_DIGITAL_SIGNATURE|KU_KEY_ENCIPHERMENT))
678 return 0;
679
680 return 1;
681}
682
683static int
684check_purpose_ns_ssl_server(const X509_PURPOSE *xp, const X509 *x, int ca)
685{
686 int ret;
687
688 ret = check_purpose_ssl_server(xp, x, ca);
689 if (!ret || ca)
690 return ret;
691 /* We need to encipher or Netscape complains */
692 if (ku_reject(x, KU_KEY_ENCIPHERMENT))
693 return 0;
694 return ret;
695}
696
697/* common S/MIME checks */
698static int
699purpose_smime(const X509 *x, int ca)
700{
701 if (xku_reject(x, XKU_SMIME))
702 return 0;
703 if (ca) {
704 int ca_ret;
705 ca_ret = check_ca(x);
706 if (!ca_ret)
707 return 0;
708 /* check nsCertType if present */
709 if (ca_ret != 5 || x->ex_nscert & NS_SMIME_CA)
710 return ca_ret;
711 else
712 return 0;
713 }
714 if (x->ex_flags & EXFLAG_NSCERT) {
715 if (x->ex_nscert & NS_SMIME)
716 return 1;
717 /* Workaround for some buggy certificates */
718 if (x->ex_nscert & NS_SSL_CLIENT)
719 return 2;
720 return 0;
721 }
722 return 1;
723}
724
725static int
726check_purpose_smime_sign(const X509_PURPOSE *xp, const X509 *x, int ca)
727{
728 int ret;
729
730 ret = purpose_smime(x, ca);
731 if (!ret || ca)
732 return ret;
733 if (ku_reject(x, KU_DIGITAL_SIGNATURE|KU_NON_REPUDIATION))
734 return 0;
735 return ret;
736}
737
738static int
739check_purpose_smime_encrypt(const X509_PURPOSE *xp, const X509 *x, int ca)
740{
741 int ret;
742
743 ret = purpose_smime(x, ca);
744 if (!ret || ca)
745 return ret;
746 if (ku_reject(x, KU_KEY_ENCIPHERMENT))
747 return 0;
748 return ret;
749}
750
751static int
752check_purpose_crl_sign(const X509_PURPOSE *xp, const X509 *x, int ca)
753{
754 if (ca) {
755 int ca_ret;
756 if ((ca_ret = check_ca(x)) != 2)
757 return ca_ret;
758 else
759 return 0;
760 }
761 if (ku_reject(x, KU_CRL_SIGN))
762 return 0;
763 return 1;
764}
765
766/* OCSP helper: this is *not* a full OCSP check. It just checks that
767 * each CA is valid. Additional checks must be made on the chain.
768 */
769static int
770ocsp_helper(const X509_PURPOSE *xp, const X509 *x, int ca)
771{
772 /* Must be a valid CA. Should we really support the "I don't know"
773 value (2)? */
774 if (ca)
775 return check_ca(x);
776 /* leaf certificate is checked in OCSP_verify() */
777 return 1;
778}
779
780static int
781check_purpose_timestamp_sign(const X509_PURPOSE *xp, const X509 *x, int ca)
782{
783 int i_ext;
784
785 /* If ca is true we must return if this is a valid CA certificate. */
786 if (ca)
787 return check_ca(x);
788
789 /*
790 * Check the optional key usage field:
791 * if Key Usage is present, it must be one of digitalSignature
792 * and/or nonRepudiation (other values are not consistent and shall
793 * be rejected).
794 */
795 if ((x->ex_flags & EXFLAG_KUSAGE) &&
796 ((x->ex_kusage & ~(KU_NON_REPUDIATION | KU_DIGITAL_SIGNATURE)) ||
797 !(x->ex_kusage & (KU_NON_REPUDIATION | KU_DIGITAL_SIGNATURE))))
798 return 0;
799
800 /* Only time stamp key usage is permitted and it's required. */
801 if (!(x->ex_flags & EXFLAG_XKUSAGE) || x->ex_xkusage != XKU_TIMESTAMP)
802 return 0;
803
804 /* Extended Key Usage MUST be critical */
805 i_ext = X509_get_ext_by_NID((X509 *) x, NID_ext_key_usage, -1);
806 if (i_ext >= 0) {
807 X509_EXTENSION *ext = X509_get_ext((X509 *) x, i_ext);
808 if (!X509_EXTENSION_get_critical(ext))
809 return 0;
810 }
811
812 return 1;
813}
814
815static int
816no_check(const X509_PURPOSE *xp, const X509 *x, int ca)
817{
818 return 1;
819}
820
821/* Various checks to see if one certificate issued the second.
822 * This can be used to prune a set of possible issuer certificates
823 * which have been looked up using some simple method such as by
824 * subject name.
825 * These are:
826 * 1. Check issuer_name(subject) == subject_name(issuer)
827 * 2. If akid(subject) exists check it matches issuer
828 * 3. If key_usage(issuer) exists check it supports certificate signing
829 * returns 0 for OK, positive for reason for mismatch, reasons match
830 * codes for X509_verify_cert()
831 */
832
833int
834X509_check_issued(X509 *issuer, X509 *subject)
835{
836 if (X509_NAME_cmp(X509_get_subject_name(issuer),
837 X509_get_issuer_name(subject)))
838 return X509_V_ERR_SUBJECT_ISSUER_MISMATCH;
839 x509v3_cache_extensions(issuer);
840 x509v3_cache_extensions(subject);
841
842 if (subject->akid) {
843 int ret = X509_check_akid(issuer, subject->akid);
844 if (ret != X509_V_OK)
845 return ret;
846 }
847
848 if (subject->ex_flags & EXFLAG_PROXY) {
849 if (ku_reject(issuer, KU_DIGITAL_SIGNATURE))
850 return X509_V_ERR_KEYUSAGE_NO_DIGITAL_SIGNATURE;
851 } else if (ku_reject(issuer, KU_KEY_CERT_SIGN))
852 return X509_V_ERR_KEYUSAGE_NO_CERTSIGN;
853 return X509_V_OK;
854}
855
856int
857X509_check_akid(X509 *issuer, AUTHORITY_KEYID *akid)
858{
859 if (!akid)
860 return X509_V_OK;
861
862 /* Check key ids (if present) */
863 if (akid->keyid && issuer->skid &&
864 ASN1_OCTET_STRING_cmp(akid->keyid, issuer->skid) )
865 return X509_V_ERR_AKID_SKID_MISMATCH;
866 /* Check serial number */
867 if (akid->serial &&
868 ASN1_INTEGER_cmp(X509_get_serialNumber(issuer), akid->serial))
869 return X509_V_ERR_AKID_ISSUER_SERIAL_MISMATCH;
870 /* Check issuer name */
871 if (akid->issuer) {
872 /* Ugh, for some peculiar reason AKID includes
873 * SEQUENCE OF GeneralName. So look for a DirName.
874 * There may be more than one but we only take any
875 * notice of the first.
876 */
877 GENERAL_NAMES *gens;
878 GENERAL_NAME *gen;
879 X509_NAME *nm = NULL;
880 int i;
881 gens = akid->issuer;
882 for (i = 0; i < sk_GENERAL_NAME_num(gens); i++) {
883 gen = sk_GENERAL_NAME_value(gens, i);
884 if (gen->type == GEN_DIRNAME) {
885 nm = gen->d.dirn;
886 break;
887 }
888 }
889 if (nm && X509_NAME_cmp(nm, X509_get_issuer_name(issuer)))
890 return X509_V_ERR_AKID_ISSUER_SERIAL_MISMATCH;
891 }
892 return X509_V_OK;
893}
generated by cgit v1.2.3-55-g6feb (git 2.39.1) at 2025-08-15 17:14:39 +0000