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source: vbox/trunk/src/libs/openssl-1.1.1h/crypto/x509/x509_vfy.c@ 86560

Last change on this file since 86560 was 86560, checked in by vboxsync, 5 years ago

openssl-1.1.1h: Applied our OpenSSL changes to 1.1.1h. Didn't check te build. bugref:9847
File size: 105.4 KB
Line 
1/*
2 * Copyright 1995-2020 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the OpenSSL license (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 <stdio.h>
11#include <time.h>
12#include <errno.h>
13#include <limits.h>
14
15#include "crypto/ctype.h"
16#include "internal/cryptlib.h"
17#include <openssl/crypto.h>
18#include <openssl/buffer.h>
19#include <openssl/evp.h>
20#include <openssl/asn1.h>
21#include <openssl/x509.h>
22#include <openssl/x509v3.h>
23#include <openssl/objects.h>
24#include "internal/dane.h"
25#include "crypto/x509.h"
26#include "x509_local.h"
27
28/* CRL score values */
29
30/* No unhandled critical extensions */
31
32#define CRL_SCORE_NOCRITICAL 0x100
33
34/* certificate is within CRL scope */
35
36#define CRL_SCORE_SCOPE 0x080
37
38/* CRL times valid */
39
40#define CRL_SCORE_TIME 0x040
41
42/* Issuer name matches certificate */
43
44#define CRL_SCORE_ISSUER_NAME 0x020
45
46/* If this score or above CRL is probably valid */
47
48#define CRL_SCORE_VALID (CRL_SCORE_NOCRITICAL|CRL_SCORE_TIME|CRL_SCORE_SCOPE)
49
50/* CRL issuer is certificate issuer */
51
52#define CRL_SCORE_ISSUER_CERT 0x018
53
54/* CRL issuer is on certificate path */
55
56#define CRL_SCORE_SAME_PATH 0x008
57
58/* CRL issuer matches CRL AKID */
59
60#define CRL_SCORE_AKID 0x004
61
62/* Have a delta CRL with valid times */
63
64#define CRL_SCORE_TIME_DELTA 0x002
65
66static int build_chain(X509_STORE_CTX *ctx);
67static int verify_chain(X509_STORE_CTX *ctx);
68static int dane_verify(X509_STORE_CTX *ctx);
69static int null_callback(int ok, X509_STORE_CTX *e);
70static int check_issued(X509_STORE_CTX *ctx, X509 *x, X509 *issuer);
71static X509 *find_issuer(X509_STORE_CTX *ctx, STACK_OF(X509) *sk, X509 *x);
72static int check_chain_extensions(X509_STORE_CTX *ctx);
73static int check_name_constraints(X509_STORE_CTX *ctx);
74static int check_id(X509_STORE_CTX *ctx);
75static int check_trust(X509_STORE_CTX *ctx, int num_untrusted);
76static int check_revocation(X509_STORE_CTX *ctx);
77static int check_cert(X509_STORE_CTX *ctx);
78static int check_policy(X509_STORE_CTX *ctx);
79static int get_issuer_sk(X509 **issuer, X509_STORE_CTX *ctx, X509 *x);
80static int check_dane_issuer(X509_STORE_CTX *ctx, int depth);
81static int check_key_level(X509_STORE_CTX *ctx, X509 *cert);
82static int check_sig_level(X509_STORE_CTX *ctx, X509 *cert);
83static int check_curve(X509 *cert);
84
85static int get_crl_score(X509_STORE_CTX *ctx, X509 **pissuer,
86 unsigned int *preasons, X509_CRL *crl, X509 *x);
87static int get_crl_delta(X509_STORE_CTX *ctx,
88 X509_CRL **pcrl, X509_CRL **pdcrl, X509 *x);
89static void get_delta_sk(X509_STORE_CTX *ctx, X509_CRL **dcrl,
90 int *pcrl_score, X509_CRL *base,
91 STACK_OF(X509_CRL) *crls);
92static void crl_akid_check(X509_STORE_CTX *ctx, X509_CRL *crl, X509 **pissuer,
93 int *pcrl_score);
94static int crl_crldp_check(X509 *x, X509_CRL *crl, int crl_score,
95 unsigned int *preasons);
96static int check_crl_path(X509_STORE_CTX *ctx, X509 *x);
97static int check_crl_chain(X509_STORE_CTX *ctx,
98 STACK_OF(X509) *cert_path,
99 STACK_OF(X509) *crl_path);
100
101static int internal_verify(X509_STORE_CTX *ctx);
102
103static int null_callback(int ok, X509_STORE_CTX *e)
104{
105 return ok;
106}
107
108/*
109 * Return 1 if given cert is considered self-signed, 0 if not or on error.
110 * This does not verify self-signedness but relies on x509v3_cache_extensions()
111 * matching issuer and subject names (i.e., the cert being self-issued) and any
112 * present authority key identifier matching the subject key identifier, etc.
113 */
114static int cert_self_signed(X509 *x)
115{
116 if (X509_check_purpose(x, -1, 0) != 1)
117 return 0;
118 if (x->ex_flags & EXFLAG_SS)
119 return 1;
120 else
121 return 0;
122}
123
124/* Given a certificate try and find an exact match in the store */
125
126static X509 *lookup_cert_match(X509_STORE_CTX *ctx, X509 *x)
127{
128 STACK_OF(X509) *certs;
129 X509 *xtmp = NULL;
130 int i;
131 /* Lookup all certs with matching subject name */
132 certs = ctx->lookup_certs(ctx, X509_get_subject_name(x));
133 if (certs == NULL)
134 return NULL;
135 /* Look for exact match */
136 for (i = 0; i < sk_X509_num(certs); i++) {
137 xtmp = sk_X509_value(certs, i);
138 if (!X509_cmp(xtmp, x))
139 break;
140 xtmp = NULL;
141 }
142 if (xtmp != NULL && !X509_up_ref(xtmp))
143 xtmp = NULL;
144 sk_X509_pop_free(certs, X509_free);
145 return xtmp;
146}
147
148/*-
149 * Inform the verify callback of an error.
150 * If B<x> is not NULL it is the error cert, otherwise use the chain cert at
151 * B<depth>.
152 * If B<err> is not X509_V_OK, that's the error value, otherwise leave
153 * unchanged (presumably set by the caller).
154 *
155 * Returns 0 to abort verification with an error, non-zero to continue.
156 */
157static int verify_cb_cert(X509_STORE_CTX *ctx, X509 *x, int depth, int err)
158{
159 ctx->error_depth = depth;
160 ctx->current_cert = (x != NULL) ? x : sk_X509_value(ctx->chain, depth);
161 if (err != X509_V_OK)
162 ctx->error = err;
163 return ctx->verify_cb(0, ctx);
164}
165
166/*-
167 * Inform the verify callback of an error, CRL-specific variant. Here, the
168 * error depth and certificate are already set, we just specify the error
169 * number.
170 *
171 * Returns 0 to abort verification with an error, non-zero to continue.
172 */
173static int verify_cb_crl(X509_STORE_CTX *ctx, int err)
174{
175 ctx->error = err;
176 return ctx->verify_cb(0, ctx);
177}
178
179static int check_auth_level(X509_STORE_CTX *ctx)
180{
181 int i;
182 int num = sk_X509_num(ctx->chain);
183
184 if (ctx->param->auth_level <= 0)
185 return 1;
186
187 for (i = 0; i < num; ++i) {
188 X509 *cert = sk_X509_value(ctx->chain, i);
189
190 /*
191 * We've already checked the security of the leaf key, so here we only
192 * check the security of issuer keys.
193 */
194 if (i > 0 && !check_key_level(ctx, cert) &&
195 verify_cb_cert(ctx, cert, i, X509_V_ERR_CA_KEY_TOO_SMALL) == 0)
196 return 0;
197 /*
198 * We also check the signature algorithm security of all certificates
199 * except those of the trust anchor at index num-1.
200 */
201 if (i < num - 1 && !check_sig_level(ctx, cert) &&
202 verify_cb_cert(ctx, cert, i, X509_V_ERR_CA_MD_TOO_WEAK) == 0)
203 return 0;
204 }
205 return 1;
206}
207
208static int verify_chain(X509_STORE_CTX *ctx)
209{
210 int err;
211 int ok;
212
213 /*
214 * Before either returning with an error, or continuing with CRL checks,
215 * instantiate chain public key parameters.
216 */
217 if ((ok = build_chain(ctx)) == 0 ||
218 (ok = check_chain_extensions(ctx)) == 0 ||
219 (ok = check_auth_level(ctx)) == 0 ||
220 (ok = check_id(ctx)) == 0 || 1)
221 X509_get_pubkey_parameters(NULL, ctx->chain);
222 if (ok == 0 || (ok = ctx->check_revocation(ctx)) == 0)
223 return ok;
224
225 err = X509_chain_check_suiteb(&ctx->error_depth, NULL, ctx->chain,
226 ctx->param->flags);
227 if (err != X509_V_OK) {
228 if ((ok = verify_cb_cert(ctx, NULL, ctx->error_depth, err)) == 0)
229 return ok;
230 }
231
232 /* Verify chain signatures and expiration times */
233 ok = (ctx->verify != NULL) ? ctx->verify(ctx) : internal_verify(ctx);
234 if (!ok)
235 return ok;
236
237 if ((ok = check_name_constraints(ctx)) == 0)
238 return ok;
239
240#ifndef OPENSSL_NO_RFC3779
241 /* RFC 3779 path validation, now that CRL check has been done */
242 if ((ok = X509v3_asid_validate_path(ctx)) == 0)
243 return ok;
244 if ((ok = X509v3_addr_validate_path(ctx)) == 0)
245 return ok;
246#endif
247
248 /* If we get this far evaluate policies */
249 if (ctx->param->flags & X509_V_FLAG_POLICY_CHECK)
250 ok = ctx->check_policy(ctx);
251 return ok;
252}
253
254int X509_verify_cert(X509_STORE_CTX *ctx)
255{
256 SSL_DANE *dane = ctx->dane;
257 int ret;
258
259 if (ctx->cert == NULL) {
260 X509err(X509_F_X509_VERIFY_CERT, X509_R_NO_CERT_SET_FOR_US_TO_VERIFY);
261 ctx->error = X509_V_ERR_INVALID_CALL;
262 return -1;
263 }
264
265 if (ctx->chain != NULL) {
266 /*
267 * This X509_STORE_CTX has already been used to verify a cert. We
268 * cannot do another one.
269 */
270 X509err(X509_F_X509_VERIFY_CERT, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
271 ctx->error = X509_V_ERR_INVALID_CALL;
272 return -1;
273 }
274
275 if (!X509_up_ref(ctx->cert)) {
276 X509err(X509_F_X509_VERIFY_CERT, ERR_R_INTERNAL_ERROR);
277 ctx->error = X509_V_ERR_UNSPECIFIED;
278 return -1;
279 }
280
281 /*
282 * first we make sure the chain we are going to build is present and that
283 * the first entry is in place
284 */
285 if ((ctx->chain = sk_X509_new_null()) == NULL
286 || !sk_X509_push(ctx->chain, ctx->cert)) {
287 X509_free(ctx->cert);
288 X509err(X509_F_X509_VERIFY_CERT, ERR_R_MALLOC_FAILURE);
289 ctx->error = X509_V_ERR_OUT_OF_MEM;
290 return -1;
291 }
292
293 ctx->num_untrusted = 1;
294
295 /* If the peer's public key is too weak, we can stop early. */
296 if (!check_key_level(ctx, ctx->cert) &&
297 !verify_cb_cert(ctx, ctx->cert, 0, X509_V_ERR_EE_KEY_TOO_SMALL))
298 return 0;
299
300 if (DANETLS_ENABLED(dane))
301 ret = dane_verify(ctx);
302 else
303 ret = verify_chain(ctx);
304
305 /*
306 * Safety-net. If we are returning an error, we must also set ctx->error,
307 * so that the chain is not considered verified should the error be ignored
308 * (e.g. TLS with SSL_VERIFY_NONE).
309 */
310 if (ret <= 0 && ctx->error == X509_V_OK)
311 ctx->error = X509_V_ERR_UNSPECIFIED;
312 return ret;
313}
314
315/*
316 * Given a STACK_OF(X509) find the issuer of cert (if any)
317 */
318static X509 *find_issuer(X509_STORE_CTX *ctx, STACK_OF(X509) *sk, X509 *x)
319{
320 int i;
321 X509 *issuer, *rv = NULL;
322
323 for (i = 0; i < sk_X509_num(sk); i++) {
324 issuer = sk_X509_value(sk, i);
325 if (ctx->check_issued(ctx, x, issuer)) {
326 rv = issuer;
327 if (x509_check_cert_time(ctx, rv, -1))
328 break;
329 }
330 }
331 return rv;
332}
333
334/*
335 * Check that the given certificate 'x' is issued by the certificate 'issuer'
336 * and the issuer is not yet in ctx->chain, where the exceptional case
337 * that 'x' is self-issued and ctx->chain has just one element is allowed.
338 */
339static int check_issued(X509_STORE_CTX *ctx, X509 *x, X509 *issuer)
340{
341 if (x509_likely_issued(issuer, x) != X509_V_OK)
342 return 0;
343 if ((x->ex_flags & EXFLAG_SI) == 0 || sk_X509_num(ctx->chain) != 1) {
344 int i;
345 X509 *ch;
346
347 for (i = 0; i < sk_X509_num(ctx->chain); i++) {
348 ch = sk_X509_value(ctx->chain, i);
349 if (ch == issuer || X509_cmp(ch, issuer) == 0)
350 return 0;
351 }
352 }
353 return 1;
354}
355
356/* Alternative lookup method: look from a STACK stored in other_ctx */
357
358static int get_issuer_sk(X509 **issuer, X509_STORE_CTX *ctx, X509 *x)
359{
360 *issuer = find_issuer(ctx, ctx->other_ctx, x);
361
362 if (*issuer == NULL || !X509_up_ref(*issuer))
363 goto err;
364
365 return 1;
366
367 err:
368 *issuer = NULL;
369 return 0;
370}
371
372static STACK_OF(X509) *lookup_certs_sk(X509_STORE_CTX *ctx, X509_NAME *nm)
373{
374 STACK_OF(X509) *sk = NULL;
375 X509 *x;
376 int i;
377
378 for (i = 0; i < sk_X509_num(ctx->other_ctx); i++) {
379 x = sk_X509_value(ctx->other_ctx, i);
380 if (X509_NAME_cmp(nm, X509_get_subject_name(x)) == 0) {
381 if (!X509_up_ref(x)) {
382 sk_X509_pop_free(sk, X509_free);
383 X509err(X509_F_LOOKUP_CERTS_SK, ERR_R_INTERNAL_ERROR);
384 ctx->error = X509_V_ERR_UNSPECIFIED;
385 return NULL;
386 }
387 if (sk == NULL)
388 sk = sk_X509_new_null();
389 if (sk == NULL || !sk_X509_push(sk, x)) {
390 X509_free(x);
391 sk_X509_pop_free(sk, X509_free);
392 X509err(X509_F_LOOKUP_CERTS_SK, ERR_R_MALLOC_FAILURE);
393 ctx->error = X509_V_ERR_OUT_OF_MEM;
394 return NULL;
395 }
396 }
397 }
398 return sk;
399}
400
401/*
402 * Check EE or CA certificate purpose. For trusted certificates explicit local
403 * auxiliary trust can be used to override EKU-restrictions.
404 */
405static int check_purpose(X509_STORE_CTX *ctx, X509 *x, int purpose, int depth,
406 int must_be_ca)
407{
408 int tr_ok = X509_TRUST_UNTRUSTED;
409
410 /*
411 * For trusted certificates we want to see whether any auxiliary trust
412 * settings trump the purpose constraints.
413 *
414 * This is complicated by the fact that the trust ordinals in
415 * ctx->param->trust are entirely independent of the purpose ordinals in
416 * ctx->param->purpose!
417 *
418 * What connects them is their mutual initialization via calls from
419 * X509_STORE_CTX_set_default() into X509_VERIFY_PARAM_lookup() which sets
420 * related values of both param->trust and param->purpose. It is however
421 * typically possible to infer associated trust values from a purpose value
422 * via the X509_PURPOSE API.
423 *
424 * Therefore, we can only check for trust overrides when the purpose we're
425 * checking is the same as ctx->param->purpose and ctx->param->trust is
426 * also set.
427 */
428 if (depth >= ctx->num_untrusted && purpose == ctx->param->purpose)
429 tr_ok = X509_check_trust(x, ctx->param->trust, X509_TRUST_NO_SS_COMPAT);
430
431 switch (tr_ok) {
432 case X509_TRUST_TRUSTED:
433 return 1;
434 case X509_TRUST_REJECTED:
435 break;
436 default:
437 switch (X509_check_purpose(x, purpose, must_be_ca > 0)) {
438 case 1:
439 return 1;
440 case 0:
441 break;
442 default:
443 if ((ctx->param->flags & X509_V_FLAG_X509_STRICT) == 0)
444 return 1;
445 }
446 break;
447 }
448
449 return verify_cb_cert(ctx, x, depth, X509_V_ERR_INVALID_PURPOSE);
450}
451
452/*
453 * Check a certificate chains extensions for consistency with the supplied
454 * purpose
455 */
456
457static int check_chain_extensions(X509_STORE_CTX *ctx)
458{
459 int i, must_be_ca, plen = 0;
460 X509 *x;
461 int proxy_path_length = 0;
462 int purpose;
463 int allow_proxy_certs;
464 int num = sk_X509_num(ctx->chain);
465
466 /*-
467 * must_be_ca can have 1 of 3 values:
468 * -1: we accept both CA and non-CA certificates, to allow direct
469 * use of self-signed certificates (which are marked as CA).
470 * 0: we only accept non-CA certificates. This is currently not
471 * used, but the possibility is present for future extensions.
472 * 1: we only accept CA certificates. This is currently used for
473 * all certificates in the chain except the leaf certificate.
474 */
475 must_be_ca = -1;
476
477 /* CRL path validation */
478 if (ctx->parent) {
479 allow_proxy_certs = 0;
480 purpose = X509_PURPOSE_CRL_SIGN;
481 } else {
482 allow_proxy_certs =
483 ! !(ctx->param->flags & X509_V_FLAG_ALLOW_PROXY_CERTS);
484 purpose = ctx->param->purpose;
485 }
486
487 for (i = 0; i < num; i++) {
488 int ret;
489 x = sk_X509_value(ctx->chain, i);
490 if (!(ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL)
491 && (x->ex_flags & EXFLAG_CRITICAL)) {
492 if (!verify_cb_cert(ctx, x, i,
493 X509_V_ERR_UNHANDLED_CRITICAL_EXTENSION))
494 return 0;
495 }
496 if (!allow_proxy_certs && (x->ex_flags & EXFLAG_PROXY)) {
497 if (!verify_cb_cert(ctx, x, i,
498 X509_V_ERR_PROXY_CERTIFICATES_NOT_ALLOWED))
499 return 0;
500 }
501 ret = X509_check_ca(x);
502 switch (must_be_ca) {
503 case -1:
504 if ((ctx->param->flags & X509_V_FLAG_X509_STRICT)
505 && (ret != 1) && (ret != 0)) {
506 ret = 0;
507 ctx->error = X509_V_ERR_INVALID_CA;
508 } else
509 ret = 1;
510 break;
511 case 0:
512 if (ret != 0) {
513 ret = 0;
514 ctx->error = X509_V_ERR_INVALID_NON_CA;
515 } else
516 ret = 1;
517 break;
518 default:
519 /* X509_V_FLAG_X509_STRICT is implicit for intermediate CAs */
520 if ((ret == 0)
521 || ((i + 1 < num || ctx->param->flags & X509_V_FLAG_X509_STRICT)
522 && (ret != 1))) {
523 ret = 0;
524 ctx->error = X509_V_ERR_INVALID_CA;
525 } else
526 ret = 1;
527 break;
528 }
529 if ((ctx->param->flags & X509_V_FLAG_X509_STRICT) && num > 1) {
530 /* Check for presence of explicit elliptic curve parameters */
531 ret = check_curve(x);
532 if (ret < 0)
533 ctx->error = X509_V_ERR_UNSPECIFIED;
534 else if (ret == 0)
535 ctx->error = X509_V_ERR_EC_KEY_EXPLICIT_PARAMS;
536 }
537 if ((x->ex_flags & EXFLAG_CA) == 0
538 && x->ex_pathlen != -1
539 && (ctx->param->flags & X509_V_FLAG_X509_STRICT)) {
540 ctx->error = X509_V_ERR_INVALID_EXTENSION;
541 ret = 0;
542 }
543 if (ret == 0 && !verify_cb_cert(ctx, x, i, X509_V_OK))
544 return 0;
545 /* check_purpose() makes the callback as needed */
546 if (purpose > 0 && !check_purpose(ctx, x, purpose, i, must_be_ca))
547 return 0;
548 /* Check pathlen */
549 if ((i > 1) && (x->ex_pathlen != -1)
550 && (plen > (x->ex_pathlen + proxy_path_length))) {
551 if (!verify_cb_cert(ctx, x, i, X509_V_ERR_PATH_LENGTH_EXCEEDED))
552 return 0;
553 }
554 /* Increment path length if not a self issued intermediate CA */
555 if (i > 0 && (x->ex_flags & EXFLAG_SI) == 0)
556 plen++;
557 /*
558 * If this certificate is a proxy certificate, the next certificate
559 * must be another proxy certificate or a EE certificate. If not,
560 * the next certificate must be a CA certificate.
561 */
562 if (x->ex_flags & EXFLAG_PROXY) {
563 /*
564 * RFC3820, 4.1.3 (b)(1) stipulates that if pCPathLengthConstraint
565 * is less than max_path_length, the former should be copied to
566 * the latter, and 4.1.4 (a) stipulates that max_path_length
567 * should be verified to be larger than zero and decrement it.
568 *
569 * Because we're checking the certs in the reverse order, we start
570 * with verifying that proxy_path_length isn't larger than pcPLC,
571 * and copy the latter to the former if it is, and finally,
572 * increment proxy_path_length.
573 */
574 if (x->ex_pcpathlen != -1) {
575 if (proxy_path_length > x->ex_pcpathlen) {
576 if (!verify_cb_cert(ctx, x, i,
577 X509_V_ERR_PROXY_PATH_LENGTH_EXCEEDED))
578 return 0;
579 }
580 proxy_path_length = x->ex_pcpathlen;
581 }
582 proxy_path_length++;
583 must_be_ca = 0;
584 } else
585 must_be_ca = 1;
586 }
587 return 1;
588}
589
590static int has_san_id(X509 *x, int gtype)
591{
592 int i;
593 int ret = 0;
594 GENERAL_NAMES *gs = X509_get_ext_d2i(x, NID_subject_alt_name, NULL, NULL);
595
596 if (gs == NULL)
597 return 0;
598
599 for (i = 0; i < sk_GENERAL_NAME_num(gs); i++) {
600 GENERAL_NAME *g = sk_GENERAL_NAME_value(gs, i);
601
602 if (g->type == gtype) {
603 ret = 1;
604 break;
605 }
606 }
607 GENERAL_NAMES_free(gs);
608 return ret;
609}
610
611static int check_name_constraints(X509_STORE_CTX *ctx)
612{
613 int i;
614
615 /* Check name constraints for all certificates */
616 for (i = sk_X509_num(ctx->chain) - 1; i >= 0; i--) {
617 X509 *x = sk_X509_value(ctx->chain, i);
618 int j;
619
620 /* Ignore self issued certs unless last in chain */
621 if (i && (x->ex_flags & EXFLAG_SI))
622 continue;
623
624 /*
625 * Proxy certificates policy has an extra constraint, where the
626 * certificate subject MUST be the issuer with a single CN entry
627 * added.
628 * (RFC 3820: 3.4, 4.1.3 (a)(4))
629 */
630 if (x->ex_flags & EXFLAG_PROXY) {
631 X509_NAME *tmpsubject = X509_get_subject_name(x);
632 X509_NAME *tmpissuer = X509_get_issuer_name(x);
633 X509_NAME_ENTRY *tmpentry = NULL;
634 int last_object_nid = 0;
635 int err = X509_V_OK;
636 int last_object_loc = X509_NAME_entry_count(tmpsubject) - 1;
637
638 /* Check that there are at least two RDNs */
639 if (last_object_loc < 1) {
640 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
641 goto proxy_name_done;
642 }
643
644 /*
645 * Check that there is exactly one more RDN in subject as
646 * there is in issuer.
647 */
648 if (X509_NAME_entry_count(tmpsubject)
649 != X509_NAME_entry_count(tmpissuer) + 1) {
650 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
651 goto proxy_name_done;
652 }
653
654 /*
655 * Check that the last subject component isn't part of a
656 * multivalued RDN
657 */
658 if (X509_NAME_ENTRY_set(X509_NAME_get_entry(tmpsubject,
659 last_object_loc))
660 == X509_NAME_ENTRY_set(X509_NAME_get_entry(tmpsubject,
661 last_object_loc - 1))) {
662 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
663 goto proxy_name_done;
664 }
665
666 /*
667 * Check that the last subject RDN is a commonName, and that
668 * all the previous RDNs match the issuer exactly
669 */
670 tmpsubject = X509_NAME_dup(tmpsubject);
671 if (tmpsubject == NULL) {
672 X509err(X509_F_CHECK_NAME_CONSTRAINTS, ERR_R_MALLOC_FAILURE);
673 ctx->error = X509_V_ERR_OUT_OF_MEM;
674 return 0;
675 }
676
677 tmpentry =
678 X509_NAME_delete_entry(tmpsubject, last_object_loc);
679 last_object_nid =
680 OBJ_obj2nid(X509_NAME_ENTRY_get_object(tmpentry));
681
682 if (last_object_nid != NID_commonName
683 || X509_NAME_cmp(tmpsubject, tmpissuer) != 0) {
684 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
685 }
686
687 X509_NAME_ENTRY_free(tmpentry);
688 X509_NAME_free(tmpsubject);
689
690 proxy_name_done:
691 if (err != X509_V_OK
692 && !verify_cb_cert(ctx, x, i, err))
693 return 0;
694 }
695
696 /*
697 * Check against constraints for all certificates higher in chain
698 * including trust anchor. Trust anchor not strictly speaking needed
699 * but if it includes constraints it is to be assumed it expects them
700 * to be obeyed.
701 */
702 for (j = sk_X509_num(ctx->chain) - 1; j > i; j--) {
703 NAME_CONSTRAINTS *nc = sk_X509_value(ctx->chain, j)->nc;
704
705 if (nc) {
706 int rv = NAME_CONSTRAINTS_check(x, nc);
707
708 /* If EE certificate check commonName too */
709 if (rv == X509_V_OK && i == 0
710 && (ctx->param->hostflags
711 & X509_CHECK_FLAG_NEVER_CHECK_SUBJECT) == 0
712 && ((ctx->param->hostflags
713 & X509_CHECK_FLAG_ALWAYS_CHECK_SUBJECT) != 0
714 || !has_san_id(x, GEN_DNS)))
715 rv = NAME_CONSTRAINTS_check_CN(x, nc);
716
717 switch (rv) {
718 case X509_V_OK:
719 break;
720 case X509_V_ERR_OUT_OF_MEM:
721 return 0;
722 default:
723 if (!verify_cb_cert(ctx, x, i, rv))
724 return 0;
725 break;
726 }
727 }
728 }
729 }
730 return 1;
731}
732
733static int check_id_error(X509_STORE_CTX *ctx, int errcode)
734{
735 return verify_cb_cert(ctx, ctx->cert, 0, errcode);
736}
737
738static int check_hosts(X509 *x, X509_VERIFY_PARAM *vpm)
739{
740 int i;
741 int n = sk_OPENSSL_STRING_num(vpm->hosts);
742 char *name;
743
744 if (vpm->peername != NULL) {
745 OPENSSL_free(vpm->peername);
746 vpm->peername = NULL;
747 }
748 for (i = 0; i < n; ++i) {
749 name = sk_OPENSSL_STRING_value(vpm->hosts, i);
750 if (X509_check_host(x, name, 0, vpm->hostflags, &vpm->peername) > 0)
751 return 1;
752 }
753 return n == 0;
754}
755
756static int check_id(X509_STORE_CTX *ctx)
757{
758 X509_VERIFY_PARAM *vpm = ctx->param;
759 X509 *x = ctx->cert;
760 if (vpm->hosts && check_hosts(x, vpm) <= 0) {
761 if (!check_id_error(ctx, X509_V_ERR_HOSTNAME_MISMATCH))
762 return 0;
763 }
764 if (vpm->email && X509_check_email(x, vpm->email, vpm->emaillen, 0) <= 0) {
765 if (!check_id_error(ctx, X509_V_ERR_EMAIL_MISMATCH))
766 return 0;
767 }
768 if (vpm->ip && X509_check_ip(x, vpm->ip, vpm->iplen, 0) <= 0) {
769 if (!check_id_error(ctx, X509_V_ERR_IP_ADDRESS_MISMATCH))
770 return 0;
771 }
772 return 1;
773}
774
775static int check_trust(X509_STORE_CTX *ctx, int num_untrusted)
776{
777 int i;
778 X509 *x = NULL;
779 X509 *mx;
780 SSL_DANE *dane = ctx->dane;
781 int num = sk_X509_num(ctx->chain);
782 int trust;
783
784 /*
785 * Check for a DANE issuer at depth 1 or greater, if it is a DANE-TA(2)
786 * match, we're done, otherwise we'll merely record the match depth.
787 */
788 if (DANETLS_HAS_TA(dane) && num_untrusted > 0 && num_untrusted < num) {
789 switch (trust = check_dane_issuer(ctx, num_untrusted)) {
790 case X509_TRUST_TRUSTED:
791 case X509_TRUST_REJECTED:
792 return trust;
793 }
794 }
795
796 /*
797 * Check trusted certificates in chain at depth num_untrusted and up.
798 * Note, that depths 0..num_untrusted-1 may also contain trusted
799 * certificates, but the caller is expected to have already checked those,
800 * and wants to incrementally check just any added since.
801 */
802 for (i = num_untrusted; i < num; i++) {
803 x = sk_X509_value(ctx->chain, i);
804 trust = X509_check_trust(x, ctx->param->trust, 0);
805 /* If explicitly trusted return trusted */
806 if (trust == X509_TRUST_TRUSTED)
807 goto trusted;
808 if (trust == X509_TRUST_REJECTED)
809 goto rejected;
810 }
811
812 /*
813 * If we are looking at a trusted certificate, and accept partial chains,
814 * the chain is PKIX trusted.
815 */
816 if (num_untrusted < num) {
817 if (ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN)
818 goto trusted;
819 return X509_TRUST_UNTRUSTED;
820 }
821
822 if (num_untrusted == num && ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) {
823 /*
824 * Last-resort call with no new trusted certificates, check the leaf
825 * for a direct trust store match.
826 */
827 i = 0;
828 x = sk_X509_value(ctx->chain, i);
829 mx = lookup_cert_match(ctx, x);
830 if (!mx)
831 return X509_TRUST_UNTRUSTED;
832
833 /*
834 * Check explicit auxiliary trust/reject settings. If none are set,
835 * we'll accept X509_TRUST_UNTRUSTED when not self-signed.
836 */
837 trust = X509_check_trust(mx, ctx->param->trust, 0);
838 if (trust == X509_TRUST_REJECTED) {
839 X509_free(mx);
840 goto rejected;
841 }
842
843 /* Replace leaf with trusted match */
844 (void) sk_X509_set(ctx->chain, 0, mx);
845 X509_free(x);
846 ctx->num_untrusted = 0;
847 goto trusted;
848 }
849
850 /*
851 * If no trusted certs in chain at all return untrusted and allow
852 * standard (no issuer cert) etc errors to be indicated.
853 */
854 return X509_TRUST_UNTRUSTED;
855
856 rejected:
857 if (!verify_cb_cert(ctx, x, i, X509_V_ERR_CERT_REJECTED))
858 return X509_TRUST_REJECTED;
859 return X509_TRUST_UNTRUSTED;
860
861 trusted:
862 if (!DANETLS_ENABLED(dane))
863 return X509_TRUST_TRUSTED;
864 if (dane->pdpth < 0)
865 dane->pdpth = num_untrusted;
866 /* With DANE, PKIX alone is not trusted until we have both */
867 if (dane->mdpth >= 0)
868 return X509_TRUST_TRUSTED;
869 return X509_TRUST_UNTRUSTED;
870}
871
872static int check_revocation(X509_STORE_CTX *ctx)
873{
874 int i = 0, last = 0, ok = 0;
875 if (!(ctx->param->flags & X509_V_FLAG_CRL_CHECK))
876 return 1;
877 if (ctx->param->flags & X509_V_FLAG_CRL_CHECK_ALL)
878 last = sk_X509_num(ctx->chain) - 1;
879 else {
880 /* If checking CRL paths this isn't the EE certificate */
881 if (ctx->parent)
882 return 1;
883 last = 0;
884 }
885 for (i = 0; i <= last; i++) {
886 ctx->error_depth = i;
887 ok = check_cert(ctx);
888 if (!ok)
889 return ok;
890 }
891 return 1;
892}
893
894static int check_cert(X509_STORE_CTX *ctx)
895{
896 X509_CRL *crl = NULL, *dcrl = NULL;
897 int ok = 0;
898 int cnum = ctx->error_depth;
899 X509 *x = sk_X509_value(ctx->chain, cnum);
900
901 ctx->current_cert = x;
902 ctx->current_issuer = NULL;
903 ctx->current_crl_score = 0;
904 ctx->current_reasons = 0;
905
906 if (x->ex_flags & EXFLAG_PROXY)
907 return 1;
908
909 while (ctx->current_reasons != CRLDP_ALL_REASONS) {
910 unsigned int last_reasons = ctx->current_reasons;
911
912 /* Try to retrieve relevant CRL */
913 if (ctx->get_crl)
914 ok = ctx->get_crl(ctx, &crl, x);
915 else
916 ok = get_crl_delta(ctx, &crl, &dcrl, x);
917 /*
918 * If error looking up CRL, nothing we can do except notify callback
919 */
920 if (!ok) {
921 ok = verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL);
922 goto done;
923 }
924 ctx->current_crl = crl;
925 ok = ctx->check_crl(ctx, crl);
926 if (!ok)
927 goto done;
928
929 if (dcrl) {
930 ok = ctx->check_crl(ctx, dcrl);
931 if (!ok)
932 goto done;
933 ok = ctx->cert_crl(ctx, dcrl, x);
934 if (!ok)
935 goto done;
936 } else
937 ok = 1;
938
939 /* Don't look in full CRL if delta reason is removefromCRL */
940 if (ok != 2) {
941 ok = ctx->cert_crl(ctx, crl, x);
942 if (!ok)
943 goto done;
944 }
945
946 X509_CRL_free(crl);
947 X509_CRL_free(dcrl);
948 crl = NULL;
949 dcrl = NULL;
950 /*
951 * If reasons not updated we won't get anywhere by another iteration,
952 * so exit loop.
953 */
954 if (last_reasons == ctx->current_reasons) {
955 ok = verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL);
956 goto done;
957 }
958 }
959 done:
960 X509_CRL_free(crl);
961 X509_CRL_free(dcrl);
962
963 ctx->current_crl = NULL;
964 return ok;
965}
966
967/* Check CRL times against values in X509_STORE_CTX */
968
969static int check_crl_time(X509_STORE_CTX *ctx, X509_CRL *crl, int notify)
970{
971 time_t *ptime;
972 int i;
973
974 if (notify)
975 ctx->current_crl = crl;
976 if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME)
977 ptime = &ctx->param->check_time;
978 else if (ctx->param->flags & X509_V_FLAG_NO_CHECK_TIME)
979 return 1;
980 else
981 ptime = NULL;
982
983 i = X509_cmp_time(X509_CRL_get0_lastUpdate(crl), ptime);
984 if (i == 0) {
985 if (!notify)
986 return 0;
987 if (!verify_cb_crl(ctx, X509_V_ERR_ERROR_IN_CRL_LAST_UPDATE_FIELD))
988 return 0;
989 }
990
991 if (i > 0) {
992 if (!notify)
993 return 0;
994 if (!verify_cb_crl(ctx, X509_V_ERR_CRL_NOT_YET_VALID))
995 return 0;
996 }
997
998 if (X509_CRL_get0_nextUpdate(crl)) {
999 i = X509_cmp_time(X509_CRL_get0_nextUpdate(crl), ptime);
1000
1001 if (i == 0) {
1002 if (!notify)
1003 return 0;
1004 if (!verify_cb_crl(ctx, X509_V_ERR_ERROR_IN_CRL_NEXT_UPDATE_FIELD))
1005 return 0;
1006 }
1007 /* Ignore expiry of base CRL is delta is valid */
1008 if ((i < 0) && !(ctx->current_crl_score & CRL_SCORE_TIME_DELTA)) {
1009 if (!notify)
1010 return 0;
1011 if (!verify_cb_crl(ctx, X509_V_ERR_CRL_HAS_EXPIRED))
1012 return 0;
1013 }
1014 }
1015
1016 if (notify)
1017 ctx->current_crl = NULL;
1018
1019 return 1;
1020}
1021
1022static int get_crl_sk(X509_STORE_CTX *ctx, X509_CRL **pcrl, X509_CRL **pdcrl,
1023 X509 **pissuer, int *pscore, unsigned int *preasons,
1024 STACK_OF(X509_CRL) *crls)
1025{
1026 int i, crl_score, best_score = *pscore;
1027 unsigned int reasons, best_reasons = 0;
1028 X509 *x = ctx->current_cert;
1029 X509_CRL *crl, *best_crl = NULL;
1030 X509 *crl_issuer = NULL, *best_crl_issuer = NULL;
1031
1032 for (i = 0; i < sk_X509_CRL_num(crls); i++) {
1033 crl = sk_X509_CRL_value(crls, i);
1034 reasons = *preasons;
1035 crl_score = get_crl_score(ctx, &crl_issuer, &reasons, crl, x);
1036 if (crl_score < best_score || crl_score == 0)
1037 continue;
1038 /* If current CRL is equivalent use it if it is newer */
1039 if (crl_score == best_score && best_crl != NULL) {
1040 int day, sec;
1041 if (ASN1_TIME_diff(&day, &sec, X509_CRL_get0_lastUpdate(best_crl),
1042 X509_CRL_get0_lastUpdate(crl)) == 0)
1043 continue;
1044 /*
1045 * ASN1_TIME_diff never returns inconsistent signs for |day|
1046 * and |sec|.
1047 */
1048 if (day <= 0 && sec <= 0)
1049 continue;
1050 }
1051 best_crl = crl;
1052 best_crl_issuer = crl_issuer;
1053 best_score = crl_score;
1054 best_reasons = reasons;
1055 }
1056
1057 if (best_crl) {
1058 X509_CRL_free(*pcrl);
1059 *pcrl = best_crl;
1060 *pissuer = best_crl_issuer;
1061 *pscore = best_score;
1062 *preasons = best_reasons;
1063 X509_CRL_up_ref(best_crl);
1064 X509_CRL_free(*pdcrl);
1065 *pdcrl = NULL;
1066 get_delta_sk(ctx, pdcrl, pscore, best_crl, crls);
1067 }
1068
1069 if (best_score >= CRL_SCORE_VALID)
1070 return 1;
1071
1072 return 0;
1073}
1074
1075/*
1076 * Compare two CRL extensions for delta checking purposes. They should be
1077 * both present or both absent. If both present all fields must be identical.
1078 */
1079
1080static int crl_extension_match(X509_CRL *a, X509_CRL *b, int nid)
1081{
1082 ASN1_OCTET_STRING *exta, *extb;
1083 int i;
1084 i = X509_CRL_get_ext_by_NID(a, nid, -1);
1085 if (i >= 0) {
1086 /* Can't have multiple occurrences */
1087 if (X509_CRL_get_ext_by_NID(a, nid, i) != -1)
1088 return 0;
1089 exta = X509_EXTENSION_get_data(X509_CRL_get_ext(a, i));
1090 } else
1091 exta = NULL;
1092
1093 i = X509_CRL_get_ext_by_NID(b, nid, -1);
1094
1095 if (i >= 0) {
1096
1097 if (X509_CRL_get_ext_by_NID(b, nid, i) != -1)
1098 return 0;
1099 extb = X509_EXTENSION_get_data(X509_CRL_get_ext(b, i));
1100 } else
1101 extb = NULL;
1102
1103 if (!exta && !extb)
1104 return 1;
1105
1106 if (!exta || !extb)
1107 return 0;
1108
1109 if (ASN1_OCTET_STRING_cmp(exta, extb))
1110 return 0;
1111
1112 return 1;
1113}
1114
1115/* See if a base and delta are compatible */
1116
1117static int check_delta_base(X509_CRL *delta, X509_CRL *base)
1118{
1119 /* Delta CRL must be a delta */
1120 if (!delta->base_crl_number)
1121 return 0;
1122 /* Base must have a CRL number */
1123 if (!base->crl_number)
1124 return 0;
1125 /* Issuer names must match */
1126 if (X509_NAME_cmp(X509_CRL_get_issuer(base), X509_CRL_get_issuer(delta)))
1127 return 0;
1128 /* AKID and IDP must match */
1129 if (!crl_extension_match(delta, base, NID_authority_key_identifier))
1130 return 0;
1131 if (!crl_extension_match(delta, base, NID_issuing_distribution_point))
1132 return 0;
1133 /* Delta CRL base number must not exceed Full CRL number. */
1134 if (ASN1_INTEGER_cmp(delta->base_crl_number, base->crl_number) > 0)
1135 return 0;
1136 /* Delta CRL number must exceed full CRL number */
1137 if (ASN1_INTEGER_cmp(delta->crl_number, base->crl_number) > 0)
1138 return 1;
1139 return 0;
1140}
1141
1142/*
1143 * For a given base CRL find a delta... maybe extend to delta scoring or
1144 * retrieve a chain of deltas...
1145 */
1146
1147static void get_delta_sk(X509_STORE_CTX *ctx, X509_CRL **dcrl, int *pscore,
1148 X509_CRL *base, STACK_OF(X509_CRL) *crls)
1149{
1150 X509_CRL *delta;
1151 int i;
1152 if (!(ctx->param->flags & X509_V_FLAG_USE_DELTAS))
1153 return;
1154 if (!((ctx->current_cert->ex_flags | base->flags) & EXFLAG_FRESHEST))
1155 return;
1156 for (i = 0; i < sk_X509_CRL_num(crls); i++) {
1157 delta = sk_X509_CRL_value(crls, i);
1158 if (check_delta_base(delta, base)) {
1159 if (check_crl_time(ctx, delta, 0))
1160 *pscore |= CRL_SCORE_TIME_DELTA;
1161 X509_CRL_up_ref(delta);
1162 *dcrl = delta;
1163 return;
1164 }
1165 }
1166 *dcrl = NULL;
1167}
1168
1169/*
1170 * For a given CRL return how suitable it is for the supplied certificate
1171 * 'x'. The return value is a mask of several criteria. If the issuer is not
1172 * the certificate issuer this is returned in *pissuer. The reasons mask is
1173 * also used to determine if the CRL is suitable: if no new reasons the CRL
1174 * is rejected, otherwise reasons is updated.
1175 */
1176
1177static int get_crl_score(X509_STORE_CTX *ctx, X509 **pissuer,
1178 unsigned int *preasons, X509_CRL *crl, X509 *x)
1179{
1180
1181 int crl_score = 0;
1182 unsigned int tmp_reasons = *preasons, crl_reasons;
1183
1184 /* First see if we can reject CRL straight away */
1185
1186 /* Invalid IDP cannot be processed */
1187 if (crl->idp_flags & IDP_INVALID)
1188 return 0;
1189 /* Reason codes or indirect CRLs need extended CRL support */
1190 if (!(ctx->param->flags & X509_V_FLAG_EXTENDED_CRL_SUPPORT)) {
1191 if (crl->idp_flags & (IDP_INDIRECT | IDP_REASONS))
1192 return 0;
1193 } else if (crl->idp_flags & IDP_REASONS) {
1194 /* If no new reasons reject */
1195 if (!(crl->idp_reasons & ~tmp_reasons))
1196 return 0;
1197 }
1198 /* Don't process deltas at this stage */
1199 else if (crl->base_crl_number)
1200 return 0;
1201 /* If issuer name doesn't match certificate need indirect CRL */
1202 if (X509_NAME_cmp(X509_get_issuer_name(x), X509_CRL_get_issuer(crl))) {
1203 if (!(crl->idp_flags & IDP_INDIRECT))
1204 return 0;
1205 } else
1206 crl_score |= CRL_SCORE_ISSUER_NAME;
1207
1208 if (!(crl->flags & EXFLAG_CRITICAL))
1209 crl_score |= CRL_SCORE_NOCRITICAL;
1210
1211 /* Check expiry */
1212 if (check_crl_time(ctx, crl, 0))
1213 crl_score |= CRL_SCORE_TIME;
1214
1215 /* Check authority key ID and locate certificate issuer */
1216 crl_akid_check(ctx, crl, pissuer, &crl_score);
1217
1218 /* If we can't locate certificate issuer at this point forget it */
1219
1220 if (!(crl_score & CRL_SCORE_AKID))
1221 return 0;
1222
1223 /* Check cert for matching CRL distribution points */
1224
1225 if (crl_crldp_check(x, crl, crl_score, &crl_reasons)) {
1226 /* If no new reasons reject */
1227 if (!(crl_reasons & ~tmp_reasons))
1228 return 0;
1229 tmp_reasons |= crl_reasons;
1230 crl_score |= CRL_SCORE_SCOPE;
1231 }
1232
1233 *preasons = tmp_reasons;
1234
1235 return crl_score;
1236
1237}
1238
1239static void crl_akid_check(X509_STORE_CTX *ctx, X509_CRL *crl,
1240 X509 **pissuer, int *pcrl_score)
1241{
1242 X509 *crl_issuer = NULL;
1243 X509_NAME *cnm = X509_CRL_get_issuer(crl);
1244 int cidx = ctx->error_depth;
1245 int i;
1246
1247 if (cidx != sk_X509_num(ctx->chain) - 1)
1248 cidx++;
1249
1250 crl_issuer = sk_X509_value(ctx->chain, cidx);
1251
1252 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1253 if (*pcrl_score & CRL_SCORE_ISSUER_NAME) {
1254 *pcrl_score |= CRL_SCORE_AKID | CRL_SCORE_ISSUER_CERT;
1255 *pissuer = crl_issuer;
1256 return;
1257 }
1258 }
1259
1260 for (cidx++; cidx < sk_X509_num(ctx->chain); cidx++) {
1261 crl_issuer = sk_X509_value(ctx->chain, cidx);
1262 if (X509_NAME_cmp(X509_get_subject_name(crl_issuer), cnm))
1263 continue;
1264 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1265 *pcrl_score |= CRL_SCORE_AKID | CRL_SCORE_SAME_PATH;
1266 *pissuer = crl_issuer;
1267 return;
1268 }
1269 }
1270
1271 /* Anything else needs extended CRL support */
1272
1273 if (!(ctx->param->flags & X509_V_FLAG_EXTENDED_CRL_SUPPORT))
1274 return;
1275
1276 /*
1277 * Otherwise the CRL issuer is not on the path. Look for it in the set of
1278 * untrusted certificates.
1279 */
1280 for (i = 0; i < sk_X509_num(ctx->untrusted); i++) {
1281 crl_issuer = sk_X509_value(ctx->untrusted, i);
1282 if (X509_NAME_cmp(X509_get_subject_name(crl_issuer), cnm))
1283 continue;
1284 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1285 *pissuer = crl_issuer;
1286 *pcrl_score |= CRL_SCORE_AKID;
1287 return;
1288 }
1289 }
1290}
1291
1292/*
1293 * Check the path of a CRL issuer certificate. This creates a new
1294 * X509_STORE_CTX and populates it with most of the parameters from the
1295 * parent. This could be optimised somewhat since a lot of path checking will
1296 * be duplicated by the parent, but this will rarely be used in practice.
1297 */
1298
1299static int check_crl_path(X509_STORE_CTX *ctx, X509 *x)
1300{
1301 X509_STORE_CTX crl_ctx;
1302 int ret;
1303
1304 /* Don't allow recursive CRL path validation */
1305 if (ctx->parent)
1306 return 0;
1307 if (!X509_STORE_CTX_init(&crl_ctx, ctx->ctx, x, ctx->untrusted))
1308 return -1;
1309
1310 crl_ctx.crls = ctx->crls;
1311 /* Copy verify params across */
1312 X509_STORE_CTX_set0_param(&crl_ctx, ctx->param);
1313
1314 crl_ctx.parent = ctx;
1315 crl_ctx.verify_cb = ctx->verify_cb;
1316
1317 /* Verify CRL issuer */
1318 ret = X509_verify_cert(&crl_ctx);
1319 if (ret <= 0)
1320 goto err;
1321
1322 /* Check chain is acceptable */
1323 ret = check_crl_chain(ctx, ctx->chain, crl_ctx.chain);
1324 err:
1325 X509_STORE_CTX_cleanup(&crl_ctx);
1326 return ret;
1327}
1328
1329/*
1330 * RFC3280 says nothing about the relationship between CRL path and
1331 * certificate path, which could lead to situations where a certificate could
1332 * be revoked or validated by a CA not authorised to do so. RFC5280 is more
1333 * strict and states that the two paths must end in the same trust anchor,
1334 * though some discussions remain... until this is resolved we use the
1335 * RFC5280 version
1336 */
1337
1338static int check_crl_chain(X509_STORE_CTX *ctx,
1339 STACK_OF(X509) *cert_path,
1340 STACK_OF(X509) *crl_path)
1341{
1342 X509 *cert_ta, *crl_ta;
1343 cert_ta = sk_X509_value(cert_path, sk_X509_num(cert_path) - 1);
1344 crl_ta = sk_X509_value(crl_path, sk_X509_num(crl_path) - 1);
1345 if (!X509_cmp(cert_ta, crl_ta))
1346 return 1;
1347 return 0;
1348}
1349
1350/*-
1351 * Check for match between two dist point names: three separate cases.
1352 * 1. Both are relative names and compare X509_NAME types.
1353 * 2. One full, one relative. Compare X509_NAME to GENERAL_NAMES.
1354 * 3. Both are full names and compare two GENERAL_NAMES.
1355 * 4. One is NULL: automatic match.
1356 */
1357
1358static int idp_check_dp(DIST_POINT_NAME *a, DIST_POINT_NAME *b)
1359{
1360 X509_NAME *nm = NULL;
1361 GENERAL_NAMES *gens = NULL;
1362 GENERAL_NAME *gena, *genb;
1363 int i, j;
1364 if (!a || !b)
1365 return 1;
1366 if (a->type == 1) {
1367 if (!a->dpname)
1368 return 0;
1369 /* Case 1: two X509_NAME */
1370 if (b->type == 1) {
1371 if (!b->dpname)
1372 return 0;
1373 if (!X509_NAME_cmp(a->dpname, b->dpname))
1374 return 1;
1375 else
1376 return 0;
1377 }
1378 /* Case 2: set name and GENERAL_NAMES appropriately */
1379 nm = a->dpname;
1380 gens = b->name.fullname;
1381 } else if (b->type == 1) {
1382 if (!b->dpname)
1383 return 0;
1384 /* Case 2: set name and GENERAL_NAMES appropriately */
1385 gens = a->name.fullname;
1386 nm = b->dpname;
1387 }
1388
1389 /* Handle case 2 with one GENERAL_NAMES and one X509_NAME */
1390 if (nm) {
1391 for (i = 0; i < sk_GENERAL_NAME_num(gens); i++) {
1392 gena = sk_GENERAL_NAME_value(gens, i);
1393 if (gena->type != GEN_DIRNAME)
1394 continue;
1395 if (!X509_NAME_cmp(nm, gena->d.directoryName))
1396 return 1;
1397 }
1398 return 0;
1399 }
1400
1401 /* Else case 3: two GENERAL_NAMES */
1402
1403 for (i = 0; i < sk_GENERAL_NAME_num(a->name.fullname); i++) {
1404 gena = sk_GENERAL_NAME_value(a->name.fullname, i);
1405 for (j = 0; j < sk_GENERAL_NAME_num(b->name.fullname); j++) {
1406 genb = sk_GENERAL_NAME_value(b->name.fullname, j);
1407 if (!GENERAL_NAME_cmp(gena, genb))
1408 return 1;
1409 }
1410 }
1411
1412 return 0;
1413
1414}
1415
1416static int crldp_check_crlissuer(DIST_POINT *dp, X509_CRL *crl, int crl_score)
1417{
1418 int i;
1419 X509_NAME *nm = X509_CRL_get_issuer(crl);
1420 /* If no CRLissuer return is successful iff don't need a match */
1421 if (!dp->CRLissuer)
1422 return ! !(crl_score & CRL_SCORE_ISSUER_NAME);
1423 for (i = 0; i < sk_GENERAL_NAME_num(dp->CRLissuer); i++) {
1424 GENERAL_NAME *gen = sk_GENERAL_NAME_value(dp->CRLissuer, i);
1425 if (gen->type != GEN_DIRNAME)
1426 continue;
1427 if (!X509_NAME_cmp(gen->d.directoryName, nm))
1428 return 1;
1429 }
1430 return 0;
1431}
1432
1433/* Check CRLDP and IDP */
1434
1435static int crl_crldp_check(X509 *x, X509_CRL *crl, int crl_score,
1436 unsigned int *preasons)
1437{
1438 int i;
1439 if (crl->idp_flags & IDP_ONLYATTR)
1440 return 0;
1441 if (x->ex_flags & EXFLAG_CA) {
1442 if (crl->idp_flags & IDP_ONLYUSER)
1443 return 0;
1444 } else {
1445 if (crl->idp_flags & IDP_ONLYCA)
1446 return 0;
1447 }
1448 *preasons = crl->idp_reasons;
1449 for (i = 0; i < sk_DIST_POINT_num(x->crldp); i++) {
1450 DIST_POINT *dp = sk_DIST_POINT_value(x->crldp, i);
1451 if (crldp_check_crlissuer(dp, crl, crl_score)) {
1452 if (!crl->idp || idp_check_dp(dp->distpoint, crl->idp->distpoint)) {
1453 *preasons &= dp->dp_reasons;
1454 return 1;
1455 }
1456 }
1457 }
1458 if ((!crl->idp || !crl->idp->distpoint)
1459 && (crl_score & CRL_SCORE_ISSUER_NAME))
1460 return 1;
1461 return 0;
1462}
1463
1464/*
1465 * Retrieve CRL corresponding to current certificate. If deltas enabled try
1466 * to find a delta CRL too
1467 */
1468
1469static int get_crl_delta(X509_STORE_CTX *ctx,
1470 X509_CRL **pcrl, X509_CRL **pdcrl, X509 *x)
1471{
1472 int ok;
1473 X509 *issuer = NULL;
1474 int crl_score = 0;
1475 unsigned int reasons;
1476 X509_CRL *crl = NULL, *dcrl = NULL;
1477 STACK_OF(X509_CRL) *skcrl;
1478 X509_NAME *nm = X509_get_issuer_name(x);
1479
1480 reasons = ctx->current_reasons;
1481 ok = get_crl_sk(ctx, &crl, &dcrl,
1482 &issuer, &crl_score, &reasons, ctx->crls);
1483 if (ok)
1484 goto done;
1485
1486 /* Lookup CRLs from store */
1487
1488 skcrl = ctx->lookup_crls(ctx, nm);
1489
1490 /* If no CRLs found and a near match from get_crl_sk use that */
1491 if (!skcrl && crl)
1492 goto done;
1493
1494 get_crl_sk(ctx, &crl, &dcrl, &issuer, &crl_score, &reasons, skcrl);
1495
1496 sk_X509_CRL_pop_free(skcrl, X509_CRL_free);
1497
1498 done:
1499 /* If we got any kind of CRL use it and return success */
1500 if (crl) {
1501 ctx->current_issuer = issuer;
1502 ctx->current_crl_score = crl_score;
1503 ctx->current_reasons = reasons;
1504 *pcrl = crl;
1505 *pdcrl = dcrl;
1506 return 1;
1507 }
1508 return 0;
1509}
1510
1511/* Check CRL validity */
1512static int check_crl(X509_STORE_CTX *ctx, X509_CRL *crl)
1513{
1514 X509 *issuer = NULL;
1515 EVP_PKEY *ikey = NULL;
1516 int cnum = ctx->error_depth;
1517 int chnum = sk_X509_num(ctx->chain) - 1;
1518
1519 /* if we have an alternative CRL issuer cert use that */
1520 if (ctx->current_issuer)
1521 issuer = ctx->current_issuer;
1522 /*
1523 * Else find CRL issuer: if not last certificate then issuer is next
1524 * certificate in chain.
1525 */
1526 else if (cnum < chnum)
1527 issuer = sk_X509_value(ctx->chain, cnum + 1);
1528 else {
1529 issuer = sk_X509_value(ctx->chain, chnum);
1530 /* If not self signed, can't check signature */
1531 if (!ctx->check_issued(ctx, issuer, issuer) &&
1532 !verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL_ISSUER))
1533 return 0;
1534 }
1535
1536 if (issuer == NULL)
1537 return 1;
1538
1539 /*
1540 * Skip most tests for deltas because they have already been done
1541 */
1542 if (!crl->base_crl_number) {
1543 /* Check for cRLSign bit if keyUsage present */
1544 if ((issuer->ex_flags & EXFLAG_KUSAGE) &&
1545 !(issuer->ex_kusage & KU_CRL_SIGN) &&
1546 !verify_cb_crl(ctx, X509_V_ERR_KEYUSAGE_NO_CRL_SIGN))
1547 return 0;
1548
1549 if (!(ctx->current_crl_score & CRL_SCORE_SCOPE) &&
1550 !verify_cb_crl(ctx, X509_V_ERR_DIFFERENT_CRL_SCOPE))
1551 return 0;
1552
1553 if (!(ctx->current_crl_score & CRL_SCORE_SAME_PATH) &&
1554 check_crl_path(ctx, ctx->current_issuer) <= 0 &&
1555 !verify_cb_crl(ctx, X509_V_ERR_CRL_PATH_VALIDATION_ERROR))
1556 return 0;
1557
1558 if ((crl->idp_flags & IDP_INVALID) &&
1559 !verify_cb_crl(ctx, X509_V_ERR_INVALID_EXTENSION))
1560 return 0;
1561 }
1562
1563 if (!(ctx->current_crl_score & CRL_SCORE_TIME) &&
1564 !check_crl_time(ctx, crl, 1))
1565 return 0;
1566
1567 /* Attempt to get issuer certificate public key */
1568 ikey = X509_get0_pubkey(issuer);
1569
1570 if (!ikey &&
1571 !verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY))
1572 return 0;
1573
1574 if (ikey) {
1575 int rv = X509_CRL_check_suiteb(crl, ikey, ctx->param->flags);
1576
1577 if (rv != X509_V_OK && !verify_cb_crl(ctx, rv))
1578 return 0;
1579 /* Verify CRL signature */
1580 if (X509_CRL_verify(crl, ikey) <= 0 &&
1581 !verify_cb_crl(ctx, X509_V_ERR_CRL_SIGNATURE_FAILURE))
1582 return 0;
1583 }
1584 return 1;
1585}
1586
1587/* Check certificate against CRL */
1588static int cert_crl(X509_STORE_CTX *ctx, X509_CRL *crl, X509 *x)
1589{
1590 X509_REVOKED *rev;
1591
1592 /*
1593 * The rules changed for this... previously if a CRL contained unhandled
1594 * critical extensions it could still be used to indicate a certificate
1595 * was revoked. This has since been changed since critical extensions can
1596 * change the meaning of CRL entries.
1597 */
1598 if (!(ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL)
1599 && (crl->flags & EXFLAG_CRITICAL) &&
1600 !verify_cb_crl(ctx, X509_V_ERR_UNHANDLED_CRITICAL_CRL_EXTENSION))
1601 return 0;
1602 /*
1603 * Look for serial number of certificate in CRL. If found, make sure
1604 * reason is not removeFromCRL.
1605 */
1606 if (X509_CRL_get0_by_cert(crl, &rev, x)) {
1607 if (rev->reason == CRL_REASON_REMOVE_FROM_CRL)
1608 return 2;
1609 if (!verify_cb_crl(ctx, X509_V_ERR_CERT_REVOKED))
1610 return 0;
1611 }
1612
1613 return 1;
1614}
1615
1616static int check_policy(X509_STORE_CTX *ctx)
1617{
1618 int ret;
1619
1620 if (ctx->parent)
1621 return 1;
1622 /*
1623 * With DANE, the trust anchor might be a bare public key, not a
1624 * certificate! In that case our chain does not have the trust anchor
1625 * certificate as a top-most element. This comports well with RFC5280
1626 * chain verification, since there too, the trust anchor is not part of the
1627 * chain to be verified. In particular, X509_policy_check() does not look
1628 * at the TA cert, but assumes that it is present as the top-most chain
1629 * element. We therefore temporarily push a NULL cert onto the chain if it
1630 * was verified via a bare public key, and pop it off right after the
1631 * X509_policy_check() call.
1632 */
1633 if (ctx->bare_ta_signed && !sk_X509_push(ctx->chain, NULL)) {
1634 X509err(X509_F_CHECK_POLICY, ERR_R_MALLOC_FAILURE);
1635 ctx->error = X509_V_ERR_OUT_OF_MEM;
1636 return 0;
1637 }
1638 ret = X509_policy_check(&ctx->tree, &ctx->explicit_policy, ctx->chain,
1639 ctx->param->policies, ctx->param->flags);
1640 if (ctx->bare_ta_signed)
1641 sk_X509_pop(ctx->chain);
1642
1643 if (ret == X509_PCY_TREE_INTERNAL) {
1644 X509err(X509_F_CHECK_POLICY, ERR_R_MALLOC_FAILURE);
1645 ctx->error = X509_V_ERR_OUT_OF_MEM;
1646 return 0;
1647 }
1648 /* Invalid or inconsistent extensions */
1649 if (ret == X509_PCY_TREE_INVALID) {
1650 int i;
1651
1652 /* Locate certificates with bad extensions and notify callback. */
1653 for (i = 1; i < sk_X509_num(ctx->chain); i++) {
1654 X509 *x = sk_X509_value(ctx->chain, i);
1655
1656 if (!(x->ex_flags & EXFLAG_INVALID_POLICY))
1657 continue;
1658 if (!verify_cb_cert(ctx, x, i,
1659 X509_V_ERR_INVALID_POLICY_EXTENSION))
1660 return 0;
1661 }
1662 return 1;
1663 }
1664 if (ret == X509_PCY_TREE_FAILURE) {
1665 ctx->current_cert = NULL;
1666 ctx->error = X509_V_ERR_NO_EXPLICIT_POLICY;
1667 return ctx->verify_cb(0, ctx);
1668 }
1669 if (ret != X509_PCY_TREE_VALID) {
1670 X509err(X509_F_CHECK_POLICY, ERR_R_INTERNAL_ERROR);
1671 return 0;
1672 }
1673
1674 if (ctx->param->flags & X509_V_FLAG_NOTIFY_POLICY) {
1675 ctx->current_cert = NULL;
1676 /*
1677 * Verification errors need to be "sticky", a callback may have allowed
1678 * an SSL handshake to continue despite an error, and we must then
1679 * remain in an error state. Therefore, we MUST NOT clear earlier
1680 * verification errors by setting the error to X509_V_OK.
1681 */
1682 if (!ctx->verify_cb(2, ctx))
1683 return 0;
1684 }
1685
1686 return 1;
1687}
1688
1689/*-
1690 * Check certificate validity times.
1691 * If depth >= 0, invoke verification callbacks on error, otherwise just return
1692 * the validation status.
1693 *
1694 * Return 1 on success, 0 otherwise.
1695 */
1696int x509_check_cert_time(X509_STORE_CTX *ctx, X509 *x, int depth)
1697{
1698 time_t *ptime;
1699 int i;
1700
1701 if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME)
1702 ptime = &ctx->param->check_time;
1703 else if (ctx->param->flags & X509_V_FLAG_NO_CHECK_TIME)
1704 return 1;
1705 else
1706 ptime = NULL;
1707
1708 i = X509_cmp_time(X509_get0_notBefore(x), ptime);
1709 if (i >= 0 && depth < 0)
1710 return 0;
1711 if (i == 0 && !verify_cb_cert(ctx, x, depth,
1712 X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD))
1713 return 0;
1714 if (i > 0 && !verify_cb_cert(ctx, x, depth, X509_V_ERR_CERT_NOT_YET_VALID))
1715 return 0;
1716
1717 i = X509_cmp_time(X509_get0_notAfter(x), ptime);
1718 if (i <= 0 && depth < 0)
1719 return 0;
1720 if (i == 0 && !verify_cb_cert(ctx, x, depth,
1721 X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD))
1722 return 0;
1723 if (i < 0 && !verify_cb_cert(ctx, x, depth, X509_V_ERR_CERT_HAS_EXPIRED))
1724 return 0;
1725 return 1;
1726}
1727
1728/* verify the issuer signatures and cert times of ctx->chain */
1729static int internal_verify(X509_STORE_CTX *ctx)
1730{
1731 int n = sk_X509_num(ctx->chain) - 1;
1732 X509 *xi = sk_X509_value(ctx->chain, n);
1733 X509 *xs;
1734
1735 /*
1736 * With DANE-verified bare public key TA signatures, it remains only to
1737 * check the timestamps of the top certificate. We report the issuer as
1738 * NULL, since all we have is a bare key.
1739 */
1740 if (ctx->bare_ta_signed) {
1741 xs = xi;
1742 xi = NULL;
1743 goto check_cert;
1744 }
1745
1746 if (ctx->check_issued(ctx, xi, xi))
1747 xs = xi; /* the typical case: last cert in the chain is self-issued */
1748 else {
1749 if (ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) {
1750 xs = xi;
1751 goto check_cert;
1752 }
1753 if (n <= 0)
1754 return verify_cb_cert(ctx, xi, 0,
1755 X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE);
1756 n--;
1757 ctx->error_depth = n;
1758 xs = sk_X509_value(ctx->chain, n);
1759 }
1760
1761 /*
1762 * Do not clear ctx->error=0, it must be "sticky", only the user's callback
1763 * is allowed to reset errors (at its own peril).
1764 */
1765 while (n >= 0) {
1766 /*
1767 * For each iteration of this loop:
1768 * n is the subject depth
1769 * xs is the subject cert, for which the signature is to be checked
1770 * xi is the supposed issuer cert containing the public key to use
1771 * Initially xs == xi if the last cert in the chain is self-issued.
1772 *
1773 * Skip signature check for self-signed certificates unless explicitly
1774 * asked for because it does not add any security and just wastes time.
1775 */
1776 if (xs != xi || ((ctx->param->flags & X509_V_FLAG_CHECK_SS_SIGNATURE)
1777 && (xi->ex_flags & EXFLAG_SS) != 0)) {
1778 EVP_PKEY *pkey;
1779 /*
1780 * If the issuer's public key is not available or its key usage
1781 * does not support issuing the subject cert, report the issuer
1782 * cert and its depth (rather than n, the depth of the subject).
1783 */
1784 int issuer_depth = n + (xs == xi ? 0 : 1);
1785 /*
1786 * According to https://tools.ietf.org/html/rfc5280#section-6.1.4
1787 * step (n) we must check any given key usage extension in a CA cert
1788 * when preparing the verification of a certificate issued by it.
1789 * According to https://tools.ietf.org/html/rfc5280#section-4.2.1.3
1790 * we must not verify a certifiate signature if the key usage of the
1791 * CA certificate that issued the certificate prohibits signing.
1792 * In case the 'issuing' certificate is the last in the chain and is
1793 * not a CA certificate but a 'self-issued' end-entity cert (i.e.,
1794 * xs == xi && !(xi->ex_flags & EXFLAG_CA)) RFC 5280 does not apply
1795 * (see https://tools.ietf.org/html/rfc6818#section-2) and thus
1796 * we are free to ignore any key usage restrictions on such certs.
1797 */
1798 int ret = xs == xi && (xi->ex_flags & EXFLAG_CA) == 0
1799 ? X509_V_OK : x509_signing_allowed(xi, xs);
1800
1801 if (ret != X509_V_OK && !verify_cb_cert(ctx, xi, issuer_depth, ret))
1802 return 0;
1803 if ((pkey = X509_get0_pubkey(xi)) == NULL) {
1804 ret = X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY;
1805 if (!verify_cb_cert(ctx, xi, issuer_depth, ret))
1806 return 0;
1807 } else if (X509_verify(xs, pkey) <= 0) {
1808 ret = X509_V_ERR_CERT_SIGNATURE_FAILURE;
1809 if (!verify_cb_cert(ctx, xs, n, ret))
1810 return 0;
1811 }
1812 }
1813
1814 check_cert:
1815 /* Calls verify callback as needed */
1816 if (!x509_check_cert_time(ctx, xs, n))
1817 return 0;
1818
1819 /*
1820 * Signal success at this depth. However, the previous error (if any)
1821 * is retained.
1822 */
1823 ctx->current_issuer = xi;
1824 ctx->current_cert = xs;
1825 ctx->error_depth = n;
1826 if (!ctx->verify_cb(1, ctx))
1827 return 0;
1828
1829 if (--n >= 0) {
1830 xi = xs;
1831 xs = sk_X509_value(ctx->chain, n);
1832 }
1833 }
1834 return 1;
1835}
1836
1837int X509_cmp_current_time(const ASN1_TIME *ctm)
1838{
1839 return X509_cmp_time(ctm, NULL);
1840}
1841
1842int X509_cmp_time(const ASN1_TIME *ctm, time_t *cmp_time)
1843{
1844 static const size_t utctime_length = sizeof("YYMMDDHHMMSSZ") - 1;
1845 static const size_t generalizedtime_length = sizeof("YYYYMMDDHHMMSSZ") - 1;
1846 ASN1_TIME *asn1_cmp_time = NULL;
1847 int i, day, sec, ret = 0;
1848#ifdef CHARSET_EBCDIC
1849 const char upper_z = 0x5A;
1850#else
1851 const char upper_z = 'Z';
1852#endif
1853 /*
1854 * Note that ASN.1 allows much more slack in the time format than RFC5280.
1855 * In RFC5280, the representation is fixed:
1856 * UTCTime: YYMMDDHHMMSSZ
1857 * GeneralizedTime: YYYYMMDDHHMMSSZ
1858 *
1859 * We do NOT currently enforce the following RFC 5280 requirement:
1860 * "CAs conforming to this profile MUST always encode certificate
1861 * validity dates through the year 2049 as UTCTime; certificate validity
1862 * dates in 2050 or later MUST be encoded as GeneralizedTime."
1863 */
1864 switch (ctm->type) {
1865 case V_ASN1_UTCTIME:
1866 if (ctm->length != (int)(utctime_length))
1867 return 0;
1868 break;
1869 case V_ASN1_GENERALIZEDTIME:
1870 if (ctm->length != (int)(generalizedtime_length))
1871 return 0;
1872 break;
1873 default:
1874 return 0;
1875 }
1876
1877 /**
1878 * Verify the format: the ASN.1 functions we use below allow a more
1879 * flexible format than what's mandated by RFC 5280.
1880 * Digit and date ranges will be verified in the conversion methods.
1881 */
1882 for (i = 0; i < ctm->length - 1; i++) {
1883 if (!ascii_isdigit(ctm->data[i]))
1884 return 0;
1885 }
1886 if (ctm->data[ctm->length - 1] != upper_z)
1887 return 0;
1888
1889 /*
1890 * There is ASN1_UTCTIME_cmp_time_t but no
1891 * ASN1_GENERALIZEDTIME_cmp_time_t or ASN1_TIME_cmp_time_t,
1892 * so we go through ASN.1
1893 */
1894 asn1_cmp_time = X509_time_adj(NULL, 0, cmp_time);
1895 if (asn1_cmp_time == NULL)
1896 goto err;
1897 if (!ASN1_TIME_diff(&day, &sec, ctm, asn1_cmp_time))
1898 goto err;
1899
1900 /*
1901 * X509_cmp_time comparison is <=.
1902 * The return value 0 is reserved for errors.
1903 */
1904 ret = (day >= 0 && sec >= 0) ? -1 : 1;
1905
1906 err:
1907 ASN1_TIME_free(asn1_cmp_time);
1908 return ret;
1909}
1910
1911ASN1_TIME *X509_gmtime_adj(ASN1_TIME *s, long adj)
1912{
1913 return X509_time_adj(s, adj, NULL);
1914}
1915
1916ASN1_TIME *X509_time_adj(ASN1_TIME *s, long offset_sec, time_t *in_tm)
1917{
1918 return X509_time_adj_ex(s, 0, offset_sec, in_tm);
1919}
1920
1921ASN1_TIME *X509_time_adj_ex(ASN1_TIME *s,
1922 int offset_day, long offset_sec, time_t *in_tm)
1923{
1924 time_t t;
1925
1926 if (in_tm)
1927 t = *in_tm;
1928 else
1929 time(&t);
1930
1931 if (s && !(s->flags & ASN1_STRING_FLAG_MSTRING)) {
1932 if (s->type == V_ASN1_UTCTIME)
1933 return ASN1_UTCTIME_adj(s, t, offset_day, offset_sec);
1934 if (s->type == V_ASN1_GENERALIZEDTIME)
1935 return ASN1_GENERALIZEDTIME_adj(s, t, offset_day, offset_sec);
1936 }
1937 return ASN1_TIME_adj(s, t, offset_day, offset_sec);
1938}
1939
1940int X509_get_pubkey_parameters(EVP_PKEY *pkey, STACK_OF(X509) *chain)
1941{
1942 EVP_PKEY *ktmp = NULL, *ktmp2;
1943 int i, j;
1944
1945 if ((pkey != NULL) && !EVP_PKEY_missing_parameters(pkey))
1946 return 1;
1947
1948 for (i = 0; i < sk_X509_num(chain); i++) {
1949 ktmp = X509_get0_pubkey(sk_X509_value(chain, i));
1950 if (ktmp == NULL) {
1951 X509err(X509_F_X509_GET_PUBKEY_PARAMETERS,
1952 X509_R_UNABLE_TO_GET_CERTS_PUBLIC_KEY);
1953 return 0;
1954 }
1955 if (!EVP_PKEY_missing_parameters(ktmp))
1956 break;
1957 }
1958 if (ktmp == NULL) {
1959 X509err(X509_F_X509_GET_PUBKEY_PARAMETERS,
1960 X509_R_UNABLE_TO_FIND_PARAMETERS_IN_CHAIN);
1961 return 0;
1962 }
1963
1964 /* first, populate the other certs */
1965 for (j = i - 1; j >= 0; j--) {
1966 ktmp2 = X509_get0_pubkey(sk_X509_value(chain, j));
1967 EVP_PKEY_copy_parameters(ktmp2, ktmp);
1968 }
1969
1970 if (pkey != NULL)
1971 EVP_PKEY_copy_parameters(pkey, ktmp);
1972 return 1;
1973}
1974
1975/* Make a delta CRL as the diff between two full CRLs */
1976
1977X509_CRL *X509_CRL_diff(X509_CRL *base, X509_CRL *newer,
1978 EVP_PKEY *skey, const EVP_MD *md, unsigned int flags)
1979{
1980 X509_CRL *crl = NULL;
1981 int i;
1982 STACK_OF(X509_REVOKED) *revs = NULL;
1983 /* CRLs can't be delta already */
1984 if (base->base_crl_number || newer->base_crl_number) {
1985 X509err(X509_F_X509_CRL_DIFF, X509_R_CRL_ALREADY_DELTA);
1986 return NULL;
1987 }
1988 /* Base and new CRL must have a CRL number */
1989 if (!base->crl_number || !newer->crl_number) {
1990 X509err(X509_F_X509_CRL_DIFF, X509_R_NO_CRL_NUMBER);
1991 return NULL;
1992 }
1993 /* Issuer names must match */
1994 if (X509_NAME_cmp(X509_CRL_get_issuer(base), X509_CRL_get_issuer(newer))) {
1995 X509err(X509_F_X509_CRL_DIFF, X509_R_ISSUER_MISMATCH);
1996 return NULL;
1997 }
1998 /* AKID and IDP must match */
1999 if (!crl_extension_match(base, newer, NID_authority_key_identifier)) {
2000 X509err(X509_F_X509_CRL_DIFF, X509_R_AKID_MISMATCH);
2001 return NULL;
2002 }
2003 if (!crl_extension_match(base, newer, NID_issuing_distribution_point)) {
2004 X509err(X509_F_X509_CRL_DIFF, X509_R_IDP_MISMATCH);
2005 return NULL;
2006 }
2007 /* Newer CRL number must exceed full CRL number */
2008 if (ASN1_INTEGER_cmp(newer->crl_number, base->crl_number) <= 0) {
2009 X509err(X509_F_X509_CRL_DIFF, X509_R_NEWER_CRL_NOT_NEWER);
2010 return NULL;
2011 }
2012 /* CRLs must verify */
2013 if (skey && (X509_CRL_verify(base, skey) <= 0 ||
2014 X509_CRL_verify(newer, skey) <= 0)) {
2015 X509err(X509_F_X509_CRL_DIFF, X509_R_CRL_VERIFY_FAILURE);
2016 return NULL;
2017 }
2018 /* Create new CRL */
2019 crl = X509_CRL_new();
2020 if (crl == NULL || !X509_CRL_set_version(crl, 1))
2021 goto memerr;
2022 /* Set issuer name */
2023 if (!X509_CRL_set_issuer_name(crl, X509_CRL_get_issuer(newer)))
2024 goto memerr;
2025
2026 if (!X509_CRL_set1_lastUpdate(crl, X509_CRL_get0_lastUpdate(newer)))
2027 goto memerr;
2028 if (!X509_CRL_set1_nextUpdate(crl, X509_CRL_get0_nextUpdate(newer)))
2029 goto memerr;
2030
2031 /* Set base CRL number: must be critical */
2032
2033 if (!X509_CRL_add1_ext_i2d(crl, NID_delta_crl, base->crl_number, 1, 0))
2034 goto memerr;
2035
2036 /*
2037 * Copy extensions across from newest CRL to delta: this will set CRL
2038 * number to correct value too.
2039 */
2040
2041 for (i = 0; i < X509_CRL_get_ext_count(newer); i++) {
2042 X509_EXTENSION *ext;
2043 ext = X509_CRL_get_ext(newer, i);
2044 if (!X509_CRL_add_ext(crl, ext, -1))
2045 goto memerr;
2046 }
2047
2048 /* Go through revoked entries, copying as needed */
2049
2050 revs = X509_CRL_get_REVOKED(newer);
2051
2052 for (i = 0; i < sk_X509_REVOKED_num(revs); i++) {
2053 X509_REVOKED *rvn, *rvtmp;
2054 rvn = sk_X509_REVOKED_value(revs, i);
2055 /*
2056 * Add only if not also in base. TODO: need something cleverer here
2057 * for some more complex CRLs covering multiple CAs.
2058 */
2059 if (!X509_CRL_get0_by_serial(base, &rvtmp, &rvn->serialNumber)) {
2060 rvtmp = X509_REVOKED_dup(rvn);
2061 if (!rvtmp)
2062 goto memerr;
2063 if (!X509_CRL_add0_revoked(crl, rvtmp)) {
2064 X509_REVOKED_free(rvtmp);
2065 goto memerr;
2066 }
2067 }
2068 }
2069 /* TODO: optionally prune deleted entries */
2070
2071 if (skey && md && !X509_CRL_sign(crl, skey, md))
2072 goto memerr;
2073
2074 return crl;
2075
2076 memerr:
2077 X509err(X509_F_X509_CRL_DIFF, ERR_R_MALLOC_FAILURE);
2078 X509_CRL_free(crl);
2079 return NULL;
2080}
2081
2082int X509_STORE_CTX_set_ex_data(X509_STORE_CTX *ctx, int idx, void *data)
2083{
2084 return CRYPTO_set_ex_data(&ctx->ex_data, idx, data);
2085}
2086
2087void *X509_STORE_CTX_get_ex_data(X509_STORE_CTX *ctx, int idx)
2088{
2089 return CRYPTO_get_ex_data(&ctx->ex_data, idx);
2090}
2091
2092int X509_STORE_CTX_get_error(X509_STORE_CTX *ctx)
2093{
2094 return ctx->error;
2095}
2096
2097void X509_STORE_CTX_set_error(X509_STORE_CTX *ctx, int err)
2098{
2099 ctx->error = err;
2100}
2101
2102int X509_STORE_CTX_get_error_depth(X509_STORE_CTX *ctx)
2103{
2104 return ctx->error_depth;
2105}
2106
2107void X509_STORE_CTX_set_error_depth(X509_STORE_CTX *ctx, int depth)
2108{
2109 ctx->error_depth = depth;
2110}
2111
2112X509 *X509_STORE_CTX_get_current_cert(X509_STORE_CTX *ctx)
2113{
2114 return ctx->current_cert;
2115}
2116
2117void X509_STORE_CTX_set_current_cert(X509_STORE_CTX *ctx, X509 *x)
2118{
2119 ctx->current_cert = x;
2120}
2121
2122STACK_OF(X509) *X509_STORE_CTX_get0_chain(X509_STORE_CTX *ctx)
2123{
2124 return ctx->chain;
2125}
2126
2127STACK_OF(X509) *X509_STORE_CTX_get1_chain(X509_STORE_CTX *ctx)
2128{
2129 if (!ctx->chain)
2130 return NULL;
2131 return X509_chain_up_ref(ctx->chain);
2132}
2133
2134X509 *X509_STORE_CTX_get0_current_issuer(X509_STORE_CTX *ctx)
2135{
2136 return ctx->current_issuer;
2137}
2138
2139X509_CRL *X509_STORE_CTX_get0_current_crl(X509_STORE_CTX *ctx)
2140{
2141 return ctx->current_crl;
2142}
2143
2144X509_STORE_CTX *X509_STORE_CTX_get0_parent_ctx(X509_STORE_CTX *ctx)
2145{
2146 return ctx->parent;
2147}
2148
2149void X509_STORE_CTX_set_cert(X509_STORE_CTX *ctx, X509 *x)
2150{
2151 ctx->cert = x;
2152}
2153
2154void X509_STORE_CTX_set0_crls(X509_STORE_CTX *ctx, STACK_OF(X509_CRL) *sk)
2155{
2156 ctx->crls = sk;
2157}
2158
2159int X509_STORE_CTX_set_purpose(X509_STORE_CTX *ctx, int purpose)
2160{
2161 /*
2162 * XXX: Why isn't this function always used to set the associated trust?
2163 * Should there even be a VPM->trust field at all? Or should the trust
2164 * always be inferred from the purpose by X509_STORE_CTX_init().
2165 */
2166 return X509_STORE_CTX_purpose_inherit(ctx, 0, purpose, 0);
2167}
2168
2169int X509_STORE_CTX_set_trust(X509_STORE_CTX *ctx, int trust)
2170{
2171 /*
2172 * XXX: See above, this function would only be needed when the default
2173 * trust for the purpose needs an override in a corner case.
2174 */
2175 return X509_STORE_CTX_purpose_inherit(ctx, 0, 0, trust);
2176}
2177
2178/*
2179 * This function is used to set the X509_STORE_CTX purpose and trust values.
2180 * This is intended to be used when another structure has its own trust and
2181 * purpose values which (if set) will be inherited by the ctx. If they aren't
2182 * set then we will usually have a default purpose in mind which should then
2183 * be used to set the trust value. An example of this is SSL use: an SSL
2184 * structure will have its own purpose and trust settings which the
2185 * application can set: if they aren't set then we use the default of SSL
2186 * client/server.
2187 */
2188
2189int X509_STORE_CTX_purpose_inherit(X509_STORE_CTX *ctx, int def_purpose,
2190 int purpose, int trust)
2191{
2192 int idx;
2193 /* If purpose not set use default */
2194 if (!purpose)
2195 purpose = def_purpose;
2196 /* If we have a purpose then check it is valid */
2197 if (purpose) {
2198 X509_PURPOSE *ptmp;
2199 idx = X509_PURPOSE_get_by_id(purpose);
2200 if (idx == -1) {
2201 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2202 X509_R_UNKNOWN_PURPOSE_ID);
2203 return 0;
2204 }
2205 ptmp = X509_PURPOSE_get0(idx);
2206 if (ptmp->trust == X509_TRUST_DEFAULT) {
2207 idx = X509_PURPOSE_get_by_id(def_purpose);
2208 /*
2209 * XXX: In the two callers above def_purpose is always 0, which is
2210 * not a known value, so idx will always be -1. How is the
2211 * X509_TRUST_DEFAULT case actually supposed to be handled?
2212 */
2213 if (idx == -1) {
2214 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2215 X509_R_UNKNOWN_PURPOSE_ID);
2216 return 0;
2217 }
2218 ptmp = X509_PURPOSE_get0(idx);
2219 }
2220 /* If trust not set then get from purpose default */
2221 if (!trust)
2222 trust = ptmp->trust;
2223 }
2224 if (trust) {
2225 idx = X509_TRUST_get_by_id(trust);
2226 if (idx == -1) {
2227 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2228 X509_R_UNKNOWN_TRUST_ID);
2229 return 0;
2230 }
2231 }
2232
2233 if (purpose && !ctx->param->purpose)
2234 ctx->param->purpose = purpose;
2235 if (trust && !ctx->param->trust)
2236 ctx->param->trust = trust;
2237 return 1;
2238}
2239
2240X509_STORE_CTX *X509_STORE_CTX_new(void)
2241{
2242 X509_STORE_CTX *ctx = OPENSSL_zalloc(sizeof(*ctx));
2243
2244 if (ctx == NULL) {
2245 X509err(X509_F_X509_STORE_CTX_NEW, ERR_R_MALLOC_FAILURE);
2246 return NULL;
2247 }
2248 return ctx;
2249}
2250
2251void X509_STORE_CTX_free(X509_STORE_CTX *ctx)
2252{
2253 if (ctx == NULL)
2254 return;
2255
2256 X509_STORE_CTX_cleanup(ctx);
2257 OPENSSL_free(ctx);
2258}
2259
2260int X509_STORE_CTX_init(X509_STORE_CTX *ctx, X509_STORE *store, X509 *x509,
2261 STACK_OF(X509) *chain)
2262{
2263 int ret = 1;
2264
2265 ctx->ctx = store;
2266 ctx->cert = x509;
2267 ctx->untrusted = chain;
2268 ctx->crls = NULL;
2269 ctx->num_untrusted = 0;
2270 ctx->other_ctx = NULL;
2271 ctx->valid = 0;
2272 ctx->chain = NULL;
2273 ctx->error = 0;
2274 ctx->explicit_policy = 0;
2275 ctx->error_depth = 0;
2276 ctx->current_cert = NULL;
2277 ctx->current_issuer = NULL;
2278 ctx->current_crl = NULL;
2279 ctx->current_crl_score = 0;
2280 ctx->current_reasons = 0;
2281 ctx->tree = NULL;
2282 ctx->parent = NULL;
2283 ctx->dane = NULL;
2284 ctx->bare_ta_signed = 0;
2285 /* Zero ex_data to make sure we're cleanup-safe */
2286 memset(&ctx->ex_data, 0, sizeof(ctx->ex_data));
2287
2288 /* store->cleanup is always 0 in OpenSSL, if set must be idempotent */
2289 if (store)
2290 ctx->cleanup = store->cleanup;
2291 else
2292 ctx->cleanup = 0;
2293
2294 if (store && store->check_issued)
2295 ctx->check_issued = store->check_issued;
2296 else
2297 ctx->check_issued = check_issued;
2298
2299 if (store && store->get_issuer)
2300 ctx->get_issuer = store->get_issuer;
2301 else
2302 ctx->get_issuer = X509_STORE_CTX_get1_issuer;
2303
2304 if (store && store->verify_cb)
2305 ctx->verify_cb = store->verify_cb;
2306 else
2307 ctx->verify_cb = null_callback;
2308
2309 if (store && store->verify)
2310 ctx->verify = store->verify;
2311 else
2312 ctx->verify = internal_verify;
2313
2314 if (store && store->check_revocation)
2315 ctx->check_revocation = store->check_revocation;
2316 else
2317 ctx->check_revocation = check_revocation;
2318
2319 if (store && store->get_crl)
2320 ctx->get_crl = store->get_crl;
2321 else
2322 ctx->get_crl = NULL;
2323
2324 if (store && store->check_crl)
2325 ctx->check_crl = store->check_crl;
2326 else
2327 ctx->check_crl = check_crl;
2328
2329 if (store && store->cert_crl)
2330 ctx->cert_crl = store->cert_crl;
2331 else
2332 ctx->cert_crl = cert_crl;
2333
2334 if (store && store->check_policy)
2335 ctx->check_policy = store->check_policy;
2336 else
2337 ctx->check_policy = check_policy;
2338
2339 if (store && store->lookup_certs)
2340 ctx->lookup_certs = store->lookup_certs;
2341 else
2342 ctx->lookup_certs = X509_STORE_CTX_get1_certs;
2343
2344 if (store && store->lookup_crls)
2345 ctx->lookup_crls = store->lookup_crls;
2346 else
2347 ctx->lookup_crls = X509_STORE_CTX_get1_crls;
2348
2349 ctx->param = X509_VERIFY_PARAM_new();
2350 if (ctx->param == NULL) {
2351 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2352 goto err;
2353 }
2354
2355 /*
2356 * Inherit callbacks and flags from X509_STORE if not set use defaults.
2357 */
2358 if (store)
2359 ret = X509_VERIFY_PARAM_inherit(ctx->param, store->param);
2360 else
2361 ctx->param->inh_flags |= X509_VP_FLAG_DEFAULT | X509_VP_FLAG_ONCE;
2362
2363 if (ret)
2364 ret = X509_VERIFY_PARAM_inherit(ctx->param,
2365 X509_VERIFY_PARAM_lookup("default"));
2366
2367 if (ret == 0) {
2368 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2369 goto err;
2370 }
2371
2372 /*
2373 * XXX: For now, continue to inherit trust from VPM, but infer from the
2374 * purpose if this still yields the default value.
2375 */
2376 if (ctx->param->trust == X509_TRUST_DEFAULT) {
2377 int idx = X509_PURPOSE_get_by_id(ctx->param->purpose);
2378 X509_PURPOSE *xp = X509_PURPOSE_get0(idx);
2379
2380 if (xp != NULL)
2381 ctx->param->trust = X509_PURPOSE_get_trust(xp);
2382 }
2383
2384 if (CRYPTO_new_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx,
2385 &ctx->ex_data))
2386 return 1;
2387 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2388
2389 err:
2390 /*
2391 * On error clean up allocated storage, if the store context was not
2392 * allocated with X509_STORE_CTX_new() this is our last chance to do so.
2393 */
2394 X509_STORE_CTX_cleanup(ctx);
2395 return 0;
2396}
2397
2398/*
2399 * Set alternative lookup method: just a STACK of trusted certificates. This
2400 * avoids X509_STORE nastiness where it isn't needed.
2401 */
2402void X509_STORE_CTX_set0_trusted_stack(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2403{
2404 ctx->other_ctx = sk;
2405 ctx->get_issuer = get_issuer_sk;
2406 ctx->lookup_certs = lookup_certs_sk;
2407}
2408
2409void X509_STORE_CTX_cleanup(X509_STORE_CTX *ctx)
2410{
2411 /*
2412 * We need to be idempotent because, unfortunately, free() also calls
2413 * cleanup(), so the natural call sequence new(), init(), cleanup(), free()
2414 * calls cleanup() for the same object twice! Thus we must zero the
2415 * pointers below after they're freed!
2416 */
2417 /* Seems to always be 0 in OpenSSL, do this at most once. */
2418 if (ctx->cleanup != NULL) {
2419 ctx->cleanup(ctx);
2420 ctx->cleanup = NULL;
2421 }
2422 if (ctx->param != NULL) {
2423 if (ctx->parent == NULL)
2424 X509_VERIFY_PARAM_free(ctx->param);
2425 ctx->param = NULL;
2426 }
2427 X509_policy_tree_free(ctx->tree);
2428 ctx->tree = NULL;
2429 sk_X509_pop_free(ctx->chain, X509_free);
2430 ctx->chain = NULL;
2431 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx, &(ctx->ex_data));
2432 memset(&ctx->ex_data, 0, sizeof(ctx->ex_data));
2433}
2434
2435void X509_STORE_CTX_set_depth(X509_STORE_CTX *ctx, int depth)
2436{
2437 X509_VERIFY_PARAM_set_depth(ctx->param, depth);
2438}
2439
2440void X509_STORE_CTX_set_flags(X509_STORE_CTX *ctx, unsigned long flags)
2441{
2442 X509_VERIFY_PARAM_set_flags(ctx->param, flags);
2443}
2444
2445void X509_STORE_CTX_set_time(X509_STORE_CTX *ctx, unsigned long flags,
2446 time_t t)
2447{
2448 X509_VERIFY_PARAM_set_time(ctx->param, t);
2449}
2450
2451X509 *X509_STORE_CTX_get0_cert(X509_STORE_CTX *ctx)
2452{
2453 return ctx->cert;
2454}
2455
2456STACK_OF(X509) *X509_STORE_CTX_get0_untrusted(X509_STORE_CTX *ctx)
2457{
2458 return ctx->untrusted;
2459}
2460
2461void X509_STORE_CTX_set0_untrusted(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2462{
2463 ctx->untrusted = sk;
2464}
2465
2466void X509_STORE_CTX_set0_verified_chain(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2467{
2468 sk_X509_pop_free(ctx->chain, X509_free);
2469 ctx->chain = sk;
2470}
2471
2472void X509_STORE_CTX_set_verify_cb(X509_STORE_CTX *ctx,
2473 X509_STORE_CTX_verify_cb verify_cb)
2474{
2475 ctx->verify_cb = verify_cb;
2476}
2477
2478X509_STORE_CTX_verify_cb X509_STORE_CTX_get_verify_cb(X509_STORE_CTX *ctx)
2479{
2480 return ctx->verify_cb;
2481}
2482
2483void X509_STORE_CTX_set_verify(X509_STORE_CTX *ctx,
2484 X509_STORE_CTX_verify_fn verify)
2485{
2486 ctx->verify = verify;
2487}
2488
2489X509_STORE_CTX_verify_fn X509_STORE_CTX_get_verify(X509_STORE_CTX *ctx)
2490{
2491 return ctx->verify;
2492}
2493
2494X509_STORE_CTX_get_issuer_fn X509_STORE_CTX_get_get_issuer(X509_STORE_CTX *ctx)
2495{
2496 return ctx->get_issuer;
2497}
2498
2499X509_STORE_CTX_check_issued_fn X509_STORE_CTX_get_check_issued(X509_STORE_CTX *ctx)
2500{
2501 return ctx->check_issued;
2502}
2503
2504X509_STORE_CTX_check_revocation_fn X509_STORE_CTX_get_check_revocation(X509_STORE_CTX *ctx)
2505{
2506 return ctx->check_revocation;
2507}
2508
2509X509_STORE_CTX_get_crl_fn X509_STORE_CTX_get_get_crl(X509_STORE_CTX *ctx)
2510{
2511 return ctx->get_crl;
2512}
2513
2514X509_STORE_CTX_check_crl_fn X509_STORE_CTX_get_check_crl(X509_STORE_CTX *ctx)
2515{
2516 return ctx->check_crl;
2517}
2518
2519X509_STORE_CTX_cert_crl_fn X509_STORE_CTX_get_cert_crl(X509_STORE_CTX *ctx)
2520{
2521 return ctx->cert_crl;
2522}
2523
2524X509_STORE_CTX_check_policy_fn X509_STORE_CTX_get_check_policy(X509_STORE_CTX *ctx)
2525{
2526 return ctx->check_policy;
2527}
2528
2529X509_STORE_CTX_lookup_certs_fn X509_STORE_CTX_get_lookup_certs(X509_STORE_CTX *ctx)
2530{
2531 return ctx->lookup_certs;
2532}
2533
2534X509_STORE_CTX_lookup_crls_fn X509_STORE_CTX_get_lookup_crls(X509_STORE_CTX *ctx)
2535{
2536 return ctx->lookup_crls;
2537}
2538
2539X509_STORE_CTX_cleanup_fn X509_STORE_CTX_get_cleanup(X509_STORE_CTX *ctx)
2540{
2541 return ctx->cleanup;
2542}
2543
2544X509_POLICY_TREE *X509_STORE_CTX_get0_policy_tree(X509_STORE_CTX *ctx)
2545{
2546 return ctx->tree;
2547}
2548
2549int X509_STORE_CTX_get_explicit_policy(X509_STORE_CTX *ctx)
2550{
2551 return ctx->explicit_policy;
2552}
2553
2554int X509_STORE_CTX_get_num_untrusted(X509_STORE_CTX *ctx)
2555{
2556 return ctx->num_untrusted;
2557}
2558
2559int X509_STORE_CTX_set_default(X509_STORE_CTX *ctx, const char *name)
2560{
2561 const X509_VERIFY_PARAM *param;
2562 param = X509_VERIFY_PARAM_lookup(name);
2563 if (!param)
2564 return 0;
2565 return X509_VERIFY_PARAM_inherit(ctx->param, param);
2566}
2567
2568X509_VERIFY_PARAM *X509_STORE_CTX_get0_param(X509_STORE_CTX *ctx)
2569{
2570 return ctx->param;
2571}
2572
2573void X509_STORE_CTX_set0_param(X509_STORE_CTX *ctx, X509_VERIFY_PARAM *param)
2574{
2575 X509_VERIFY_PARAM_free(ctx->param);
2576 ctx->param = param;
2577}
2578
2579void X509_STORE_CTX_set0_dane(X509_STORE_CTX *ctx, SSL_DANE *dane)
2580{
2581 ctx->dane = dane;
2582}
2583
2584static unsigned char *dane_i2d(
2585 X509 *cert,
2586 uint8_t selector,
2587 unsigned int *i2dlen)
2588{
2589 unsigned char *buf = NULL;
2590 int len;
2591
2592 /*
2593 * Extract ASN.1 DER form of certificate or public key.
2594 */
2595 switch (selector) {
2596 case DANETLS_SELECTOR_CERT:
2597 len = i2d_X509(cert, &buf);
2598 break;
2599 case DANETLS_SELECTOR_SPKI:
2600 len = i2d_X509_PUBKEY(X509_get_X509_PUBKEY(cert), &buf);
2601 break;
2602 default:
2603 X509err(X509_F_DANE_I2D, X509_R_BAD_SELECTOR);
2604 return NULL;
2605 }
2606
2607 if (len < 0 || buf == NULL) {
2608 X509err(X509_F_DANE_I2D, ERR_R_MALLOC_FAILURE);
2609 return NULL;
2610 }
2611
2612 *i2dlen = (unsigned int)len;
2613 return buf;
2614}
2615
2616#define DANETLS_NONE 256 /* impossible uint8_t */
2617
2618static int dane_match(X509_STORE_CTX *ctx, X509 *cert, int depth)
2619{
2620 SSL_DANE *dane = ctx->dane;
2621 unsigned usage = DANETLS_NONE;
2622 unsigned selector = DANETLS_NONE;
2623 unsigned ordinal = DANETLS_NONE;
2624 unsigned mtype = DANETLS_NONE;
2625 unsigned char *i2dbuf = NULL;
2626 unsigned int i2dlen = 0;
2627 unsigned char mdbuf[EVP_MAX_MD_SIZE];
2628 unsigned char *cmpbuf = NULL;
2629 unsigned int cmplen = 0;
2630 int i;
2631 int recnum;
2632 int matched = 0;
2633 danetls_record *t = NULL;
2634 uint32_t mask;
2635
2636 mask = (depth == 0) ? DANETLS_EE_MASK : DANETLS_TA_MASK;
2637
2638 /*
2639 * The trust store is not applicable with DANE-TA(2)
2640 */
2641 if (depth >= ctx->num_untrusted)
2642 mask &= DANETLS_PKIX_MASK;
2643
2644 /*
2645 * If we've previously matched a PKIX-?? record, no need to test any
2646 * further PKIX-?? records, it remains to just build the PKIX chain.
2647 * Had the match been a DANE-?? record, we'd be done already.
2648 */
2649 if (dane->mdpth >= 0)
2650 mask &= ~DANETLS_PKIX_MASK;
2651
2652 /*-
2653 * https://tools.ietf.org/html/rfc7671#section-5.1
2654 * https://tools.ietf.org/html/rfc7671#section-5.2
2655 * https://tools.ietf.org/html/rfc7671#section-5.3
2656 * https://tools.ietf.org/html/rfc7671#section-5.4
2657 *
2658 * We handle DANE-EE(3) records first as they require no chain building
2659 * and no expiration or hostname checks. We also process digests with
2660 * higher ordinals first and ignore lower priorities except Full(0) which
2661 * is always processed (last). If none match, we then process PKIX-EE(1).
2662 *
2663 * NOTE: This relies on DANE usages sorting before the corresponding PKIX
2664 * usages in SSL_dane_tlsa_add(), and also on descending sorting of digest
2665 * priorities. See twin comment in ssl/ssl_lib.c.
2666 *
2667 * We expect that most TLSA RRsets will have just a single usage, so we
2668 * don't go out of our way to cache multiple selector-specific i2d buffers
2669 * across usages, but if the selector happens to remain the same as switch
2670 * usages, that's OK. Thus, a set of "3 1 1", "3 0 1", "1 1 1", "1 0 1",
2671 * records would result in us generating each of the certificate and public
2672 * key DER forms twice, but more typically we'd just see multiple "3 1 1"
2673 * or multiple "3 0 1" records.
2674 *
2675 * As soon as we find a match at any given depth, we stop, because either
2676 * we've matched a DANE-?? record and the peer is authenticated, or, after
2677 * exhausting all DANE-?? records, we've matched a PKIX-?? record, which is
2678 * sufficient for DANE, and what remains to do is ordinary PKIX validation.
2679 */
2680 recnum = (dane->umask & mask) ? sk_danetls_record_num(dane->trecs) : 0;
2681 for (i = 0; matched == 0 && i < recnum; ++i) {
2682 t = sk_danetls_record_value(dane->trecs, i);
2683 if ((DANETLS_USAGE_BIT(t->usage) & mask) == 0)
2684 continue;
2685 if (t->usage != usage) {
2686 usage = t->usage;
2687
2688 /* Reset digest agility for each usage/selector pair */
2689 mtype = DANETLS_NONE;
2690 ordinal = dane->dctx->mdord[t->mtype];
2691 }
2692 if (t->selector != selector) {
2693 selector = t->selector;
2694
2695 /* Update per-selector state */
2696 OPENSSL_free(i2dbuf);
2697 i2dbuf = dane_i2d(cert, selector, &i2dlen);
2698 if (i2dbuf == NULL)
2699 return -1;
2700
2701 /* Reset digest agility for each usage/selector pair */
2702 mtype = DANETLS_NONE;
2703 ordinal = dane->dctx->mdord[t->mtype];
2704 } else if (t->mtype != DANETLS_MATCHING_FULL) {
2705 /*-
2706 * Digest agility:
2707 *
2708 * <https://tools.ietf.org/html/rfc7671#section-9>
2709 *
2710 * For a fixed selector, after processing all records with the
2711 * highest mtype ordinal, ignore all mtypes with lower ordinals
2712 * other than "Full".
2713 */
2714 if (dane->dctx->mdord[t->mtype] < ordinal)
2715 continue;
2716 }
2717
2718 /*
2719 * Each time we hit a (new selector or) mtype, re-compute the relevant
2720 * digest, more complex caching is not worth the code space.
2721 */
2722 if (t->mtype != mtype) {
2723 const EVP_MD *md = dane->dctx->mdevp[mtype = t->mtype];
2724 cmpbuf = i2dbuf;
2725 cmplen = i2dlen;
2726
2727 if (md != NULL) {
2728 cmpbuf = mdbuf;
2729 if (!EVP_Digest(i2dbuf, i2dlen, cmpbuf, &cmplen, md, 0)) {
2730 matched = -1;
2731 break;
2732 }
2733 }
2734 }
2735
2736 /*
2737 * Squirrel away the certificate and depth if we have a match. Any
2738 * DANE match is dispositive, but with PKIX we still need to build a
2739 * full chain.
2740 */
2741 if (cmplen == t->dlen &&
2742 memcmp(cmpbuf, t->data, cmplen) == 0) {
2743 if (DANETLS_USAGE_BIT(usage) & DANETLS_DANE_MASK)
2744 matched = 1;
2745 if (matched || dane->mdpth < 0) {
2746 dane->mdpth = depth;
2747 dane->mtlsa = t;
2748 OPENSSL_free(dane->mcert);
2749 dane->mcert = cert;
2750 X509_up_ref(cert);
2751 }
2752 break;
2753 }
2754 }
2755
2756 /* Clear the one-element DER cache */
2757 OPENSSL_free(i2dbuf);
2758 return matched;
2759}
2760
2761static int check_dane_issuer(X509_STORE_CTX *ctx, int depth)
2762{
2763 SSL_DANE *dane = ctx->dane;
2764 int matched = 0;
2765 X509 *cert;
2766
2767 if (!DANETLS_HAS_TA(dane) || depth == 0)
2768 return X509_TRUST_UNTRUSTED;
2769
2770 /*
2771 * Record any DANE trust-anchor matches, for the first depth to test, if
2772 * there's one at that depth. (This'll be false for length 1 chains looking
2773 * for an exact match for the leaf certificate).
2774 */
2775 cert = sk_X509_value(ctx->chain, depth);
2776 if (cert != NULL && (matched = dane_match(ctx, cert, depth)) < 0)
2777 return X509_TRUST_REJECTED;
2778 if (matched > 0) {
2779 ctx->num_untrusted = depth - 1;
2780 return X509_TRUST_TRUSTED;
2781 }
2782
2783 return X509_TRUST_UNTRUSTED;
2784}
2785
2786static int check_dane_pkeys(X509_STORE_CTX *ctx)
2787{
2788 SSL_DANE *dane = ctx->dane;
2789 danetls_record *t;
2790 int num = ctx->num_untrusted;
2791 X509 *cert = sk_X509_value(ctx->chain, num - 1);
2792 int recnum = sk_danetls_record_num(dane->trecs);
2793 int i;
2794
2795 for (i = 0; i < recnum; ++i) {
2796 t = sk_danetls_record_value(dane->trecs, i);
2797 if (t->usage != DANETLS_USAGE_DANE_TA ||
2798 t->selector != DANETLS_SELECTOR_SPKI ||
2799 t->mtype != DANETLS_MATCHING_FULL ||
2800 X509_verify(cert, t->spki) <= 0)
2801 continue;
2802
2803 /* Clear any PKIX-?? matches that failed to extend to a full chain */
2804 X509_free(dane->mcert);
2805 dane->mcert = NULL;
2806
2807 /* Record match via a bare TA public key */
2808 ctx->bare_ta_signed = 1;
2809 dane->mdpth = num - 1;
2810 dane->mtlsa = t;
2811
2812 /* Prune any excess chain certificates */
2813 num = sk_X509_num(ctx->chain);
2814 for (; num > ctx->num_untrusted; --num)
2815 X509_free(sk_X509_pop(ctx->chain));
2816
2817 return X509_TRUST_TRUSTED;
2818 }
2819
2820 return X509_TRUST_UNTRUSTED;
2821}
2822
2823static void dane_reset(SSL_DANE *dane)
2824{
2825 /*
2826 * Reset state to verify another chain, or clear after failure.
2827 */
2828 X509_free(dane->mcert);
2829 dane->mcert = NULL;
2830 dane->mtlsa = NULL;
2831 dane->mdpth = -1;
2832 dane->pdpth = -1;
2833}
2834
2835static int check_leaf_suiteb(X509_STORE_CTX *ctx, X509 *cert)
2836{
2837 int err = X509_chain_check_suiteb(NULL, cert, NULL, ctx->param->flags);
2838
2839 if (err == X509_V_OK)
2840 return 1;
2841 return verify_cb_cert(ctx, cert, 0, err);
2842}
2843
2844static int dane_verify(X509_STORE_CTX *ctx)
2845{
2846 X509 *cert = ctx->cert;
2847 SSL_DANE *dane = ctx->dane;
2848 int matched;
2849 int done;
2850
2851 dane_reset(dane);
2852
2853 /*-
2854 * When testing the leaf certificate, if we match a DANE-EE(3) record,
2855 * dane_match() returns 1 and we're done. If however we match a PKIX-EE(1)
2856 * record, the match depth and matching TLSA record are recorded, but the
2857 * return value is 0, because we still need to find a PKIX trust-anchor.
2858 * Therefore, when DANE authentication is enabled (required), we're done
2859 * if:
2860 * + matched < 0, internal error.
2861 * + matched == 1, we matched a DANE-EE(3) record
2862 * + matched == 0, mdepth < 0 (no PKIX-EE match) and there are no
2863 * DANE-TA(2) or PKIX-TA(0) to test.
2864 */
2865 matched = dane_match(ctx, ctx->cert, 0);
2866 done = matched != 0 || (!DANETLS_HAS_TA(dane) && dane->mdpth < 0);
2867
2868 if (done)
2869 X509_get_pubkey_parameters(NULL, ctx->chain);
2870
2871 if (matched > 0) {
2872 /* Callback invoked as needed */
2873 if (!check_leaf_suiteb(ctx, cert))
2874 return 0;
2875 /* Callback invoked as needed */
2876 if ((dane->flags & DANE_FLAG_NO_DANE_EE_NAMECHECKS) == 0 &&
2877 !check_id(ctx))
2878 return 0;
2879 /* Bypass internal_verify(), issue depth 0 success callback */
2880 ctx->error_depth = 0;
2881 ctx->current_cert = cert;
2882 return ctx->verify_cb(1, ctx);
2883 }
2884
2885 if (matched < 0) {
2886 ctx->error_depth = 0;
2887 ctx->current_cert = cert;
2888 ctx->error = X509_V_ERR_OUT_OF_MEM;
2889 return -1;
2890 }
2891
2892 if (done) {
2893 /* Fail early, TA-based success is not possible */
2894 if (!check_leaf_suiteb(ctx, cert))
2895 return 0;
2896 return verify_cb_cert(ctx, cert, 0, X509_V_ERR_DANE_NO_MATCH);
2897 }
2898
2899 /*
2900 * Chain verification for usages 0/1/2. TLSA record matching of depth > 0
2901 * certificates happens in-line with building the rest of the chain.
2902 */
2903 return verify_chain(ctx);
2904}
2905
2906/* Get issuer, without duplicate suppression */
2907static int get_issuer(X509 **issuer, X509_STORE_CTX *ctx, X509 *cert)
2908{
2909 STACK_OF(X509) *saved_chain = ctx->chain;
2910 int ok;
2911
2912 ctx->chain = NULL;
2913 ok = ctx->get_issuer(issuer, ctx, cert);
2914 ctx->chain = saved_chain;
2915
2916 return ok;
2917}
2918
2919static int build_chain(X509_STORE_CTX *ctx)
2920{
2921 SSL_DANE *dane = ctx->dane;
2922 int num = sk_X509_num(ctx->chain);
2923 X509 *cert = sk_X509_value(ctx->chain, num - 1);
2924 int ss = cert_self_signed(cert);
2925 STACK_OF(X509) *sktmp = NULL;
2926 unsigned int search;
2927 int may_trusted = 0;
2928 int may_alternate = 0;
2929 int trust = X509_TRUST_UNTRUSTED;
2930 int alt_untrusted = 0;
2931 int depth;
2932 int ok = 0;
2933 int i;
2934
2935 /* Our chain starts with a single untrusted element. */
2936 if (!ossl_assert(num == 1 && ctx->num_untrusted == num)) {
2937 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
2938 ctx->error = X509_V_ERR_UNSPECIFIED;
2939 return 0;
2940 }
2941
2942#define S_DOUNTRUSTED (1 << 0) /* Search untrusted chain */
2943#define S_DOTRUSTED (1 << 1) /* Search trusted store */
2944#define S_DOALTERNATE (1 << 2) /* Retry with pruned alternate chain */
2945 /*
2946 * Set up search policy, untrusted if possible, trusted-first if enabled.
2947 * If we're doing DANE and not doing PKIX-TA/PKIX-EE, we never look in the
2948 * trust_store, otherwise we might look there first. If not trusted-first,
2949 * and alternate chains are not disabled, try building an alternate chain
2950 * if no luck with untrusted first.
2951 */
2952 search = (ctx->untrusted != NULL) ? S_DOUNTRUSTED : 0;
2953 if (DANETLS_HAS_PKIX(dane) || !DANETLS_HAS_DANE(dane)) {
2954 if (search == 0 || ctx->param->flags & X509_V_FLAG_TRUSTED_FIRST)
2955 search |= S_DOTRUSTED;
2956 else if (!(ctx->param->flags & X509_V_FLAG_NO_ALT_CHAINS))
2957 may_alternate = 1;
2958 may_trusted = 1;
2959 }
2960
2961 /*
2962 * Shallow-copy the stack of untrusted certificates (with TLS, this is
2963 * typically the content of the peer's certificate message) so can make
2964 * multiple passes over it, while free to remove elements as we go.
2965 */
2966 if (ctx->untrusted && (sktmp = sk_X509_dup(ctx->untrusted)) == NULL) {
2967 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2968 ctx->error = X509_V_ERR_OUT_OF_MEM;
2969 return 0;
2970 }
2971
2972 /*
2973 * If we got any "DANE-TA(2) Cert(0) Full(0)" trust-anchors from DNS, add
2974 * them to our working copy of the untrusted certificate stack. Since the
2975 * caller of X509_STORE_CTX_init() may have provided only a leaf cert with
2976 * no corresponding stack of untrusted certificates, we may need to create
2977 * an empty stack first. [ At present only the ssl library provides DANE
2978 * support, and ssl_verify_cert_chain() always provides a non-null stack
2979 * containing at least the leaf certificate, but we must be prepared for
2980 * this to change. ]
2981 */
2982 if (DANETLS_ENABLED(dane) && dane->certs != NULL) {
2983 if (sktmp == NULL && (sktmp = sk_X509_new_null()) == NULL) {
2984 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2985 ctx->error = X509_V_ERR_OUT_OF_MEM;
2986 return 0;
2987 }
2988 for (i = 0; i < sk_X509_num(dane->certs); ++i) {
2989 if (!sk_X509_push(sktmp, sk_X509_value(dane->certs, i))) {
2990 sk_X509_free(sktmp);
2991 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2992 ctx->error = X509_V_ERR_OUT_OF_MEM;
2993 return 0;
2994 }
2995 }
2996 }
2997
2998 /*
2999 * Still absurdly large, but arithmetically safe, a lower hard upper bound
3000 * might be reasonable.
3001 */
3002 if (ctx->param->depth > INT_MAX/2)
3003 ctx->param->depth = INT_MAX/2;
3004
3005 /*
3006 * Try to Extend the chain until we reach an ultimately trusted issuer.
3007 * Build chains up to one longer the limit, later fail if we hit the limit,
3008 * with an X509_V_ERR_CERT_CHAIN_TOO_LONG error code.
3009 */
3010 depth = ctx->param->depth + 1;
3011
3012 while (search != 0) {
3013 X509 *x;
3014 X509 *xtmp = NULL;
3015
3016 /*
3017 * Look in the trust store if enabled for first lookup, or we've run
3018 * out of untrusted issuers and search here is not disabled. When we
3019 * reach the depth limit, we stop extending the chain, if by that point
3020 * we've not found a trust-anchor, any trusted chain would be too long.
3021 *
3022 * The error reported to the application verify callback is at the
3023 * maximal valid depth with the current certificate equal to the last
3024 * not ultimately-trusted issuer. For example, with verify_depth = 0,
3025 * the callback will report errors at depth=1 when the immediate issuer
3026 * of the leaf certificate is not a trust anchor. No attempt will be
3027 * made to locate an issuer for that certificate, since such a chain
3028 * would be a-priori too long.
3029 */
3030 if ((search & S_DOTRUSTED) != 0) {
3031 i = num = sk_X509_num(ctx->chain);
3032 if ((search & S_DOALTERNATE) != 0) {
3033 /*
3034 * As high up the chain as we can, look for an alternative
3035 * trusted issuer of an untrusted certificate that currently
3036 * has an untrusted issuer. We use the alt_untrusted variable
3037 * to track how far up the chain we find the first match. It
3038 * is only if and when we find a match, that we prune the chain
3039 * and reset ctx->num_untrusted to the reduced count of
3040 * untrusted certificates. While we're searching for such a
3041 * match (which may never be found), it is neither safe nor
3042 * wise to preemptively modify either the chain or
3043 * ctx->num_untrusted.
3044 *
3045 * Note, like ctx->num_untrusted, alt_untrusted is a count of
3046 * untrusted certificates, not a "depth".
3047 */
3048 i = alt_untrusted;
3049 }
3050 x = sk_X509_value(ctx->chain, i-1);
3051
3052 ok = (depth < num) ? 0 : get_issuer(&xtmp, ctx, x);
3053
3054 if (ok < 0) {
3055 trust = X509_TRUST_REJECTED;
3056 ctx->error = X509_V_ERR_STORE_LOOKUP;
3057 search = 0;
3058 continue;
3059 }
3060
3061 if (ok > 0) {
3062 /*
3063 * Alternative trusted issuer for a mid-chain untrusted cert?
3064 * Pop the untrusted cert's successors and retry. We might now
3065 * be able to complete a valid chain via the trust store. Note
3066 * that despite the current trust-store match we might still
3067 * fail complete the chain to a suitable trust-anchor, in which
3068 * case we may prune some more untrusted certificates and try
3069 * again. Thus the S_DOALTERNATE bit may yet be turned on
3070 * again with an even shorter untrusted chain!
3071 *
3072 * If in the process we threw away our matching PKIX-TA trust
3073 * anchor, reset DANE trust. We might find a suitable trusted
3074 * certificate among the ones from the trust store.
3075 */
3076 if ((search & S_DOALTERNATE) != 0) {
3077 if (!ossl_assert(num > i && i > 0 && ss == 0)) {
3078 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
3079 X509_free(xtmp);
3080 trust = X509_TRUST_REJECTED;
3081 ctx->error = X509_V_ERR_UNSPECIFIED;
3082 search = 0;
3083 continue;
3084 }
3085 search &= ~S_DOALTERNATE;
3086 for (; num > i; --num)
3087 X509_free(sk_X509_pop(ctx->chain));
3088 ctx->num_untrusted = num;
3089
3090 if (DANETLS_ENABLED(dane) &&
3091 dane->mdpth >= ctx->num_untrusted) {
3092 dane->mdpth = -1;
3093 X509_free(dane->mcert);
3094 dane->mcert = NULL;
3095 }
3096 if (DANETLS_ENABLED(dane) &&
3097 dane->pdpth >= ctx->num_untrusted)
3098 dane->pdpth = -1;
3099 }
3100
3101 /*
3102 * Self-signed untrusted certificates get replaced by their
3103 * trusted matching issuer. Otherwise, grow the chain.
3104 */
3105 if (ss == 0) {
3106 if (!sk_X509_push(ctx->chain, x = xtmp)) {
3107 X509_free(xtmp);
3108 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
3109 trust = X509_TRUST_REJECTED;
3110 ctx->error = X509_V_ERR_OUT_OF_MEM;
3111 search = 0;
3112 continue;
3113 }
3114 ss = cert_self_signed(x);
3115 } else if (num == ctx->num_untrusted) {
3116 /*
3117 * We have a self-signed certificate that has the same
3118 * subject name (and perhaps keyid and/or serial number) as
3119 * a trust-anchor. We must have an exact match to avoid
3120 * possible impersonation via key substitution etc.
3121 */
3122 if (X509_cmp(x, xtmp) != 0) {
3123 /* Self-signed untrusted mimic. */
3124 X509_free(xtmp);
3125 ok = 0;
3126 } else {
3127 X509_free(x);
3128 ctx->num_untrusted = --num;
3129 (void) sk_X509_set(ctx->chain, num, x = xtmp);
3130 }
3131 }
3132
3133 /*
3134 * We've added a new trusted certificate to the chain, recheck
3135 * trust. If not done, and not self-signed look deeper.
3136 * Whether or not we're doing "trusted first", we no longer
3137 * look for untrusted certificates from the peer's chain.
3138 *
3139 * At this point ctx->num_trusted and num must reflect the
3140 * correct number of untrusted certificates, since the DANE
3141 * logic in check_trust() depends on distinguishing CAs from
3142 * "the wire" from CAs from the trust store. In particular, the
3143 * certificate at depth "num" should be the new trusted
3144 * certificate with ctx->num_untrusted <= num.
3145 */
3146 if (ok) {
3147 if (!ossl_assert(ctx->num_untrusted <= num)) {
3148 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
3149 trust = X509_TRUST_REJECTED;
3150 ctx->error = X509_V_ERR_UNSPECIFIED;
3151 search = 0;
3152 continue;
3153 }
3154 search &= ~S_DOUNTRUSTED;
3155 switch (trust = check_trust(ctx, num)) {
3156 case X509_TRUST_TRUSTED:
3157 case X509_TRUST_REJECTED:
3158 search = 0;
3159 continue;
3160 }
3161 if (ss == 0)
3162 continue;
3163 }
3164 }
3165
3166 /*
3167 * No dispositive decision, and either self-signed or no match, if
3168 * we were doing untrusted-first, and alt-chains are not disabled,
3169 * do that, by repeatedly losing one untrusted element at a time,
3170 * and trying to extend the shorted chain.
3171 */
3172 if ((search & S_DOUNTRUSTED) == 0) {
3173 /* Continue search for a trusted issuer of a shorter chain? */
3174 if ((search & S_DOALTERNATE) != 0 && --alt_untrusted > 0)
3175 continue;
3176 /* Still no luck and no fallbacks left? */
3177 if (!may_alternate || (search & S_DOALTERNATE) != 0 ||
3178 ctx->num_untrusted < 2)
3179 break;
3180 /* Search for a trusted issuer of a shorter chain */
3181 search |= S_DOALTERNATE;
3182 alt_untrusted = ctx->num_untrusted - 1;
3183 ss = 0;
3184 }
3185 }
3186
3187 /*
3188 * Extend chain with peer-provided certificates
3189 */
3190 if ((search & S_DOUNTRUSTED) != 0) {
3191 num = sk_X509_num(ctx->chain);
3192 if (!ossl_assert(num == ctx->num_untrusted)) {
3193 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
3194 trust = X509_TRUST_REJECTED;
3195 ctx->error = X509_V_ERR_UNSPECIFIED;
3196 search = 0;
3197 continue;
3198 }
3199 x = sk_X509_value(ctx->chain, num-1);
3200
3201 /*
3202 * Once we run out of untrusted issuers, we stop looking for more
3203 * and start looking only in the trust store if enabled.
3204 */
3205 xtmp = (ss || depth < num) ? NULL : find_issuer(ctx, sktmp, x);
3206 if (xtmp == NULL) {
3207 search &= ~S_DOUNTRUSTED;
3208 if (may_trusted)
3209 search |= S_DOTRUSTED;
3210 continue;
3211 }
3212
3213 /* Drop this issuer from future consideration */
3214 (void) sk_X509_delete_ptr(sktmp, xtmp);
3215
3216 if (!X509_up_ref(xtmp)) {
3217 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
3218 trust = X509_TRUST_REJECTED;
3219 ctx->error = X509_V_ERR_UNSPECIFIED;
3220 search = 0;
3221 continue;
3222 }
3223
3224 if (!sk_X509_push(ctx->chain, xtmp)) {
3225 X509_free(xtmp);
3226 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
3227 trust = X509_TRUST_REJECTED;
3228 ctx->error = X509_V_ERR_OUT_OF_MEM;
3229 search = 0;
3230 continue;
3231 }
3232
3233 x = xtmp;
3234 ++ctx->num_untrusted;
3235 ss = cert_self_signed(xtmp);
3236
3237 /*
3238 * Check for DANE-TA trust of the topmost untrusted certificate.
3239 */
3240 switch (trust = check_dane_issuer(ctx, ctx->num_untrusted - 1)) {
3241 case X509_TRUST_TRUSTED:
3242 case X509_TRUST_REJECTED:
3243 search = 0;
3244 continue;
3245 }
3246 }
3247 }
3248 sk_X509_free(sktmp);
3249
3250 /*
3251 * Last chance to make a trusted chain, either bare DANE-TA public-key
3252 * signers, or else direct leaf PKIX trust.
3253 */
3254 num = sk_X509_num(ctx->chain);
3255 if (num <= depth) {
3256 if (trust == X509_TRUST_UNTRUSTED && DANETLS_HAS_DANE_TA(dane))
3257 trust = check_dane_pkeys(ctx);
3258 if (trust == X509_TRUST_UNTRUSTED && num == ctx->num_untrusted)
3259 trust = check_trust(ctx, num);
3260 }
3261
3262 switch (trust) {
3263 case X509_TRUST_TRUSTED:
3264 return 1;
3265 case X509_TRUST_REJECTED:
3266 /* Callback already issued */
3267 return 0;
3268 case X509_TRUST_UNTRUSTED:
3269 default:
3270 num = sk_X509_num(ctx->chain);
3271 if (num > depth)
3272 return verify_cb_cert(ctx, NULL, num-1,
3273 X509_V_ERR_CERT_CHAIN_TOO_LONG);
3274 if (DANETLS_ENABLED(dane) &&
3275 (!DANETLS_HAS_PKIX(dane) || dane->pdpth >= 0))
3276 return verify_cb_cert(ctx, NULL, num-1, X509_V_ERR_DANE_NO_MATCH);
3277 if (ss && sk_X509_num(ctx->chain) == 1)
3278 return verify_cb_cert(ctx, NULL, num-1,
3279 X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT);
3280 if (ss)
3281 return verify_cb_cert(ctx, NULL, num-1,
3282 X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN);
3283 if (ctx->num_untrusted < num)
3284 return verify_cb_cert(ctx, NULL, num-1,
3285 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT);
3286 return verify_cb_cert(ctx, NULL, num-1,
3287 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY);
3288 }
3289}
3290
3291static const int minbits_table[] = { 80, 112, 128, 192, 256 };
3292static const int NUM_AUTH_LEVELS = OSSL_NELEM(minbits_table);
3293
3294/*
3295 * Check whether the public key of ``cert`` meets the security level of
3296 * ``ctx``.
3297 *
3298 * Returns 1 on success, 0 otherwise.
3299 */
3300static int check_key_level(X509_STORE_CTX *ctx, X509 *cert)
3301{
3302 EVP_PKEY *pkey = X509_get0_pubkey(cert);
3303 int level = ctx->param->auth_level;
3304
3305 /*
3306 * At security level zero, return without checking for a supported public
3307 * key type. Some engines support key types not understood outside the
3308 * engine, and we only need to understand the key when enforcing a security
3309 * floor.
3310 */
3311 if (level <= 0)
3312 return 1;
3313
3314 /* Unsupported or malformed keys are not secure */
3315 if (pkey == NULL)
3316 return 0;
3317
3318 if (level > NUM_AUTH_LEVELS)
3319 level = NUM_AUTH_LEVELS;
3320
3321 return EVP_PKEY_security_bits(pkey) >= minbits_table[level - 1];
3322}
3323
3324/*
3325 * Check whether the public key of ``cert`` does not use explicit params
3326 * for an elliptic curve.
3327 *
3328 * Returns 1 on success, 0 if check fails, -1 for other errors.
3329 */
3330static int check_curve(X509 *cert)
3331{
3332#ifndef OPENSSL_NO_EC
3333 EVP_PKEY *pkey = X509_get0_pubkey(cert);
3334
3335 /* Unsupported or malformed key */
3336 if (pkey == NULL)
3337 return -1;
3338
3339 if (EVP_PKEY_id(pkey) == EVP_PKEY_EC) {
3340 int ret;
3341
3342 ret = EC_KEY_decoded_from_explicit_params(EVP_PKEY_get0_EC_KEY(pkey));
3343 return ret < 0 ? ret : !ret;
3344 }
3345#endif
3346
3347 return 1;
3348}
3349
3350/*
3351 * Check whether the signature digest algorithm of ``cert`` meets the security
3352 * level of ``ctx``. Should not be checked for trust anchors (whether
3353 * self-signed or otherwise).
3354 *
3355 * Returns 1 on success, 0 otherwise.
3356 */
3357static int check_sig_level(X509_STORE_CTX *ctx, X509 *cert)
3358{
3359 int secbits = -1;
3360 int level = ctx->param->auth_level;
3361
3362 if (level <= 0)
3363 return 1;
3364 if (level > NUM_AUTH_LEVELS)
3365 level = NUM_AUTH_LEVELS;
3366
3367 if (!X509_get_signature_info(cert, NULL, NULL, &secbits, NULL))
3368 return 0;
3369
3370 return secbits >= minbits_table[level - 1];
3371}
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