Gitiles
Code Review Sign In
192.168.1.100 / R306 / e08f1058ff217e55feb109a64cd5cac3a2da9a6d / . / ap / lib / libssl / openssl-1.1.1o / crypto / x509 / x509_vfy.c
blob: b18489f67f6e48c1e58045f41fe64680b0f62cfc [file] [log] [blame]
yuezonghe824eb0c2024-06-27 02:32:26 -0700[diff] [blame]1/*
2 * Copyright 1995-2022 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
315static int sk_X509_contains(STACK_OF(X509) *sk, X509 *cert)
316{
317 int i, n = sk_X509_num(sk);
318
319 for (i = 0; i < n; i++)
320 if (X509_cmp(sk_X509_value(sk, i), cert) == 0)
321 return 1;
322 return 0;
323}
324
325/*
326 * Find in given STACK_OF(X509) sk an issuer cert of given cert x.
327 * The issuer must not yet be in ctx->chain, where the exceptional case
328 * that x is self-issued and ctx->chain has just one element is allowed.
329 * Prefer the first one that is not expired, else take the last expired one.
330 */
331static X509 *find_issuer(X509_STORE_CTX *ctx, STACK_OF(X509) *sk, X509 *x)
332{
333 int i;
334 X509 *issuer, *rv = NULL;
335
336 for (i = 0; i < sk_X509_num(sk); i++) {
337 issuer = sk_X509_value(sk, i);
338 if (ctx->check_issued(ctx, x, issuer)
339 && (((x->ex_flags & EXFLAG_SI) != 0 && sk_X509_num(ctx->chain) == 1)
340 || !sk_X509_contains(ctx->chain, issuer))) {
341 rv = issuer;
342 if (x509_check_cert_time(ctx, rv, -1))
343 break;
344 }
345 }
346 return rv;
347}
348
349/* Check that the given certificate 'x' is issued by the certificate 'issuer' */
350static int check_issued(X509_STORE_CTX *ctx, X509 *x, X509 *issuer)
351{
352 return x509_likely_issued(issuer, x) == X509_V_OK;
353}
354
355/* Alternative lookup method: look from a STACK stored in other_ctx */
356static int get_issuer_sk(X509 **issuer, X509_STORE_CTX *ctx, X509 *x)
357{
358 *issuer = find_issuer(ctx, ctx->other_ctx, x);
359
360 if (*issuer == NULL || !X509_up_ref(*issuer))
361 goto err;
362
363 return 1;
364
365 err:
366 *issuer = NULL;
367 return 0;
368}
369
370static STACK_OF(X509) *lookup_certs_sk(X509_STORE_CTX *ctx, X509_NAME *nm)
371{
372 STACK_OF(X509) *sk = NULL;
373 X509 *x;
374 int i;
375
376 for (i = 0; i < sk_X509_num(ctx->other_ctx); i++) {
377 x = sk_X509_value(ctx->other_ctx, i);
378 if (X509_NAME_cmp(nm, X509_get_subject_name(x)) == 0) {
379 if (!X509_up_ref(x)) {
380 sk_X509_pop_free(sk, X509_free);
381 X509err(X509_F_LOOKUP_CERTS_SK, ERR_R_INTERNAL_ERROR);
382 ctx->error = X509_V_ERR_UNSPECIFIED;
383 return NULL;
384 }
385 if (sk == NULL)
386 sk = sk_X509_new_null();
387 if (sk == NULL || !sk_X509_push(sk, x)) {
388 X509_free(x);
389 sk_X509_pop_free(sk, X509_free);
390 X509err(X509_F_LOOKUP_CERTS_SK, ERR_R_MALLOC_FAILURE);
391 ctx->error = X509_V_ERR_OUT_OF_MEM;
392 return NULL;
393 }
394 }
395 }
396 return sk;
397}
398
399/*
400 * Check EE or CA certificate purpose. For trusted certificates explicit local
401 * auxiliary trust can be used to override EKU-restrictions.
402 */
403static int check_purpose(X509_STORE_CTX *ctx, X509 *x, int purpose, int depth,
404 int must_be_ca)
405{
406 int tr_ok = X509_TRUST_UNTRUSTED;
407
408 /*
409 * For trusted certificates we want to see whether any auxiliary trust
410 * settings trump the purpose constraints.
411 *
412 * This is complicated by the fact that the trust ordinals in
413 * ctx->param->trust are entirely independent of the purpose ordinals in
414 * ctx->param->purpose!
415 *
416 * What connects them is their mutual initialization via calls from
417 * X509_STORE_CTX_set_default() into X509_VERIFY_PARAM_lookup() which sets
418 * related values of both param->trust and param->purpose. It is however
419 * typically possible to infer associated trust values from a purpose value
420 * via the X509_PURPOSE API.
421 *
422 * Therefore, we can only check for trust overrides when the purpose we're
423 * checking is the same as ctx->param->purpose and ctx->param->trust is
424 * also set.
425 */
426 if (depth >= ctx->num_untrusted && purpose == ctx->param->purpose)
427 tr_ok = X509_check_trust(x, ctx->param->trust, X509_TRUST_NO_SS_COMPAT);
428
429 switch (tr_ok) {
430 case X509_TRUST_TRUSTED:
431 return 1;
432 case X509_TRUST_REJECTED:
433 break;
434 default:
435 switch (X509_check_purpose(x, purpose, must_be_ca > 0)) {
436 case 1:
437 return 1;
438 case 0:
439 break;
440 default:
441 if ((ctx->param->flags & X509_V_FLAG_X509_STRICT) == 0)
442 return 1;
443 }
444 break;
445 }
446
447 return verify_cb_cert(ctx, x, depth, X509_V_ERR_INVALID_PURPOSE);
448}
449
450/*
451 * Check a certificate chains extensions for consistency with the supplied
452 * purpose
453 */
454
455static int check_chain_extensions(X509_STORE_CTX *ctx)
456{
457 int i, must_be_ca, plen = 0;
458 X509 *x;
459 int proxy_path_length = 0;
460 int purpose;
461 int allow_proxy_certs;
462 int num = sk_X509_num(ctx->chain);
463
464 /*-
465 * must_be_ca can have 1 of 3 values:
466 * -1: we accept both CA and non-CA certificates, to allow direct
467 * use of self-signed certificates (which are marked as CA).
468 * 0: we only accept non-CA certificates. This is currently not
469 * used, but the possibility is present for future extensions.
470 * 1: we only accept CA certificates. This is currently used for
471 * all certificates in the chain except the leaf certificate.
472 */
473 must_be_ca = -1;
474
475 /* CRL path validation */
476 if (ctx->parent) {
477 allow_proxy_certs = 0;
478 purpose = X509_PURPOSE_CRL_SIGN;
479 } else {
480 allow_proxy_certs =
481 ! !(ctx->param->flags & X509_V_FLAG_ALLOW_PROXY_CERTS);
482 purpose = ctx->param->purpose;
483 }
484
485 for (i = 0; i < num; i++) {
486 int ret;
487 x = sk_X509_value(ctx->chain, i);
488 if (!(ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL)
489 && (x->ex_flags & EXFLAG_CRITICAL)) {
490 if (!verify_cb_cert(ctx, x, i,
491 X509_V_ERR_UNHANDLED_CRITICAL_EXTENSION))
492 return 0;
493 }
494 if (!allow_proxy_certs && (x->ex_flags & EXFLAG_PROXY)) {
495 if (!verify_cb_cert(ctx, x, i,
496 X509_V_ERR_PROXY_CERTIFICATES_NOT_ALLOWED))
497 return 0;
498 }
499 ret = X509_check_ca(x);
500 switch (must_be_ca) {
501 case -1:
502 if ((ctx->param->flags & X509_V_FLAG_X509_STRICT)
503 && (ret != 1) && (ret != 0)) {
504 ret = 0;
505 ctx->error = X509_V_ERR_INVALID_CA;
506 } else
507 ret = 1;
508 break;
509 case 0:
510 if (ret != 0) {
511 ret = 0;
512 ctx->error = X509_V_ERR_INVALID_NON_CA;
513 } else
514 ret = 1;
515 break;
516 default:
517 /* X509_V_FLAG_X509_STRICT is implicit for intermediate CAs */
518 if ((ret == 0)
519 || ((i + 1 < num || ctx->param->flags & X509_V_FLAG_X509_STRICT)
520 && (ret != 1))) {
521 ret = 0;
522 ctx->error = X509_V_ERR_INVALID_CA;
523 } else
524 ret = 1;
525 break;
526 }
527 if (ret > 0
528 && (ctx->param->flags & X509_V_FLAG_X509_STRICT) && num > 1) {
529 /* Check for presence of explicit elliptic curve parameters */
530 ret = check_curve(x);
531 if (ret < 0) {
532 ctx->error = X509_V_ERR_UNSPECIFIED;
533 ret = 0;
534 } else if (ret == 0) {
535 ctx->error = X509_V_ERR_EC_KEY_EXPLICIT_PARAMS;
536 }
537 }
538 if (ret > 0
539 && (x->ex_flags & EXFLAG_CA) == 0
540 && x->ex_pathlen != -1
541 && (ctx->param->flags & X509_V_FLAG_X509_STRICT)) {
542 ctx->error = X509_V_ERR_INVALID_EXTENSION;
543 ret = 0;
544 }
545 if (ret == 0 && !verify_cb_cert(ctx, x, i, X509_V_OK))
546 return 0;
547 /* check_purpose() makes the callback as needed */
548 if (purpose > 0 && !check_purpose(ctx, x, purpose, i, must_be_ca))
549 return 0;
550 /* Check pathlen */
551 if ((i > 1) && (x->ex_pathlen != -1)
552 && (plen > (x->ex_pathlen + proxy_path_length))) {
553 if (!verify_cb_cert(ctx, x, i, X509_V_ERR_PATH_LENGTH_EXCEEDED))
554 return 0;
555 }
556 /* Increment path length if not a self issued intermediate CA */
557 if (i > 0 && (x->ex_flags & EXFLAG_SI) == 0)
558 plen++;
559 /*
560 * If this certificate is a proxy certificate, the next certificate
561 * must be another proxy certificate or a EE certificate. If not,
562 * the next certificate must be a CA certificate.
563 */
564 if (x->ex_flags & EXFLAG_PROXY) {
565 /*
566 * RFC3820, 4.1.3 (b)(1) stipulates that if pCPathLengthConstraint
567 * is less than max_path_length, the former should be copied to
568 * the latter, and 4.1.4 (a) stipulates that max_path_length
569 * should be verified to be larger than zero and decrement it.
570 *
571 * Because we're checking the certs in the reverse order, we start
572 * with verifying that proxy_path_length isn't larger than pcPLC,
573 * and copy the latter to the former if it is, and finally,
574 * increment proxy_path_length.
575 */
576 if (x->ex_pcpathlen != -1) {
577 if (proxy_path_length > x->ex_pcpathlen) {
578 if (!verify_cb_cert(ctx, x, i,
579 X509_V_ERR_PROXY_PATH_LENGTH_EXCEEDED))
580 return 0;
581 }
582 proxy_path_length = x->ex_pcpathlen;
583 }
584 proxy_path_length++;
585 must_be_ca = 0;
586 } else
587 must_be_ca = 1;
588 }
589 return 1;
590}
591
592static int has_san_id(X509 *x, int gtype)
593{
594 int i;
595 int ret = 0;
596 GENERAL_NAMES *gs = X509_get_ext_d2i(x, NID_subject_alt_name, NULL, NULL);
597
598 if (gs == NULL)
599 return 0;
600
601 for (i = 0; i < sk_GENERAL_NAME_num(gs); i++) {
602 GENERAL_NAME *g = sk_GENERAL_NAME_value(gs, i);
603
604 if (g->type == gtype) {
605 ret = 1;
606 break;
607 }
608 }
609 GENERAL_NAMES_free(gs);
610 return ret;
611}
612
613static int check_name_constraints(X509_STORE_CTX *ctx)
614{
615 int i;
616
617 /* Check name constraints for all certificates */
618 for (i = sk_X509_num(ctx->chain) - 1; i >= 0; i--) {
619 X509 *x = sk_X509_value(ctx->chain, i);
620 int j;
621
622 /* Ignore self issued certs unless last in chain */
623 if (i && (x->ex_flags & EXFLAG_SI))
624 continue;
625
626 /*
627 * Proxy certificates policy has an extra constraint, where the
628 * certificate subject MUST be the issuer with a single CN entry
629 * added.
630 * (RFC 3820: 3.4, 4.1.3 (a)(4))
631 */
632 if (x->ex_flags & EXFLAG_PROXY) {
633 X509_NAME *tmpsubject = X509_get_subject_name(x);
634 X509_NAME *tmpissuer = X509_get_issuer_name(x);
635 X509_NAME_ENTRY *tmpentry = NULL;
636 int last_object_nid = 0;
637 int err = X509_V_OK;
638 int last_object_loc = X509_NAME_entry_count(tmpsubject) - 1;
639
640 /* Check that there are at least two RDNs */
641 if (last_object_loc < 1) {
642 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
643 goto proxy_name_done;
644 }
645
646 /*
647 * Check that there is exactly one more RDN in subject as
648 * there is in issuer.
649 */
650 if (X509_NAME_entry_count(tmpsubject)
651 != X509_NAME_entry_count(tmpissuer) + 1) {
652 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
653 goto proxy_name_done;
654 }
655
656 /*
657 * Check that the last subject component isn't part of a
658 * multivalued RDN
659 */
660 if (X509_NAME_ENTRY_set(X509_NAME_get_entry(tmpsubject,
661 last_object_loc))
662 == X509_NAME_ENTRY_set(X509_NAME_get_entry(tmpsubject,
663 last_object_loc - 1))) {
664 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
665 goto proxy_name_done;
666 }
667
668 /*
669 * Check that the last subject RDN is a commonName, and that
670 * all the previous RDNs match the issuer exactly
671 */
672 tmpsubject = X509_NAME_dup(tmpsubject);
673 if (tmpsubject == NULL) {
674 X509err(X509_F_CHECK_NAME_CONSTRAINTS, ERR_R_MALLOC_FAILURE);
675 ctx->error = X509_V_ERR_OUT_OF_MEM;
676 return 0;
677 }
678
679 tmpentry =
680 X509_NAME_delete_entry(tmpsubject, last_object_loc);
681 last_object_nid =
682 OBJ_obj2nid(X509_NAME_ENTRY_get_object(tmpentry));
683
684 if (last_object_nid != NID_commonName
685 || X509_NAME_cmp(tmpsubject, tmpissuer) != 0) {
686 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
687 }
688
689 X509_NAME_ENTRY_free(tmpentry);
690 X509_NAME_free(tmpsubject);
691
692 proxy_name_done:
693 if (err != X509_V_OK
694 && !verify_cb_cert(ctx, x, i, err))
695 return 0;
696 }
697
698 /*
699 * Check against constraints for all certificates higher in chain
700 * including trust anchor. Trust anchor not strictly speaking needed
701 * but if it includes constraints it is to be assumed it expects them
702 * to be obeyed.
703 */
704 for (j = sk_X509_num(ctx->chain) - 1; j > i; j--) {
705 NAME_CONSTRAINTS *nc = sk_X509_value(ctx->chain, j)->nc;
706
707 if (nc) {
708 int rv = NAME_CONSTRAINTS_check(x, nc);
709
710 /* If EE certificate check commonName too */
711 if (rv == X509_V_OK && i == 0
712 && (ctx->param->hostflags
713 & X509_CHECK_FLAG_NEVER_CHECK_SUBJECT) == 0
714 && ((ctx->param->hostflags
715 & X509_CHECK_FLAG_ALWAYS_CHECK_SUBJECT) != 0
716 || !has_san_id(x, GEN_DNS)))
717 rv = NAME_CONSTRAINTS_check_CN(x, nc);
718
719 switch (rv) {
720 case X509_V_OK:
721 break;
722 case X509_V_ERR_OUT_OF_MEM:
723 return 0;
724 default:
725 if (!verify_cb_cert(ctx, x, i, rv))
726 return 0;
727 break;
728 }
729 }
730 }
731 }
732 return 1;
733}
734
735static int check_id_error(X509_STORE_CTX *ctx, int errcode)
736{
737 return verify_cb_cert(ctx, ctx->cert, 0, errcode);
738}
739
740static int check_hosts(X509 *x, X509_VERIFY_PARAM *vpm)
741{
742 int i;
743 int n = sk_OPENSSL_STRING_num(vpm->hosts);
744 char *name;
745
746 if (vpm->peername != NULL) {
747 OPENSSL_free(vpm->peername);
748 vpm->peername = NULL;
749 }
750 for (i = 0; i < n; ++i) {
751 name = sk_OPENSSL_STRING_value(vpm->hosts, i);
752 if (X509_check_host(x, name, 0, vpm->hostflags, &vpm->peername) > 0)
753 return 1;
754 }
755 return n == 0;
756}
757
758static int check_id(X509_STORE_CTX *ctx)
759{
760 X509_VERIFY_PARAM *vpm = ctx->param;
761 X509 *x = ctx->cert;
762 if (vpm->hosts && check_hosts(x, vpm) <= 0) {
763 if (!check_id_error(ctx, X509_V_ERR_HOSTNAME_MISMATCH))
764 return 0;
765 }
766 if (vpm->email && X509_check_email(x, vpm->email, vpm->emaillen, 0) <= 0) {
767 if (!check_id_error(ctx, X509_V_ERR_EMAIL_MISMATCH))
768 return 0;
769 }
770 if (vpm->ip && X509_check_ip(x, vpm->ip, vpm->iplen, 0) <= 0) {
771 if (!check_id_error(ctx, X509_V_ERR_IP_ADDRESS_MISMATCH))
772 return 0;
773 }
774 return 1;
775}
776
777static int check_trust(X509_STORE_CTX *ctx, int num_untrusted)
778{
779 int i;
780 X509 *x = NULL;
781 X509 *mx;
782 SSL_DANE *dane = ctx->dane;
783 int num = sk_X509_num(ctx->chain);
784 int trust;
785
786 /*
787 * Check for a DANE issuer at depth 1 or greater, if it is a DANE-TA(2)
788 * match, we're done, otherwise we'll merely record the match depth.
789 */
790 if (DANETLS_HAS_TA(dane) && num_untrusted > 0 && num_untrusted < num) {
791 switch (trust = check_dane_issuer(ctx, num_untrusted)) {
792 case X509_TRUST_TRUSTED:
793 case X509_TRUST_REJECTED:
794 return trust;
795 }
796 }
797
798 /*
799 * Check trusted certificates in chain at depth num_untrusted and up.
800 * Note, that depths 0..num_untrusted-1 may also contain trusted
801 * certificates, but the caller is expected to have already checked those,
802 * and wants to incrementally check just any added since.
803 */
804 for (i = num_untrusted; i < num; i++) {
805 x = sk_X509_value(ctx->chain, i);
806 trust = X509_check_trust(x, ctx->param->trust, 0);
807 /* If explicitly trusted return trusted */
808 if (trust == X509_TRUST_TRUSTED)
809 goto trusted;
810 if (trust == X509_TRUST_REJECTED)
811 goto rejected;
812 }
813
814 /*
815 * If we are looking at a trusted certificate, and accept partial chains,
816 * the chain is PKIX trusted.
817 */
818 if (num_untrusted < num) {
819 if (ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN)
820 goto trusted;
821 return X509_TRUST_UNTRUSTED;
822 }
823
824 if (num_untrusted == num && ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) {
825 /*
826 * Last-resort call with no new trusted certificates, check the leaf
827 * for a direct trust store match.
828 */
829 i = 0;
830 x = sk_X509_value(ctx->chain, i);
831 mx = lookup_cert_match(ctx, x);
832 if (!mx)
833 return X509_TRUST_UNTRUSTED;
834
835 /*
836 * Check explicit auxiliary trust/reject settings. If none are set,
837 * we'll accept X509_TRUST_UNTRUSTED when not self-signed.
838 */
839 trust = X509_check_trust(mx, ctx->param->trust, 0);
840 if (trust == X509_TRUST_REJECTED) {
841 X509_free(mx);
842 goto rejected;
843 }
844
845 /* Replace leaf with trusted match */
846 (void) sk_X509_set(ctx->chain, 0, mx);
847 X509_free(x);
848 ctx->num_untrusted = 0;
849 goto trusted;
850 }
851
852 /*
853 * If no trusted certs in chain at all return untrusted and allow
854 * standard (no issuer cert) etc errors to be indicated.
855 */
856 return X509_TRUST_UNTRUSTED;
857
858 rejected:
859 if (!verify_cb_cert(ctx, x, i, X509_V_ERR_CERT_REJECTED))
860 return X509_TRUST_REJECTED;
861 return X509_TRUST_UNTRUSTED;
862
863 trusted:
864 if (!DANETLS_ENABLED(dane))
865 return X509_TRUST_TRUSTED;
866 if (dane->pdpth < 0)
867 dane->pdpth = num_untrusted;
868 /* With DANE, PKIX alone is not trusted until we have both */
869 if (dane->mdpth >= 0)
870 return X509_TRUST_TRUSTED;
871 return X509_TRUST_UNTRUSTED;
872}
873
874static int check_revocation(X509_STORE_CTX *ctx)
875{
876 int i = 0, last = 0, ok = 0;
877 if (!(ctx->param->flags & X509_V_FLAG_CRL_CHECK))
878 return 1;
879 if (ctx->param->flags & X509_V_FLAG_CRL_CHECK_ALL)
880 last = sk_X509_num(ctx->chain) - 1;
881 else {
882 /* If checking CRL paths this isn't the EE certificate */
883 if (ctx->parent)
884 return 1;
885 last = 0;
886 }
887 for (i = 0; i <= last; i++) {
888 ctx->error_depth = i;
889 ok = check_cert(ctx);
890 if (!ok)
891 return ok;
892 }
893 return 1;
894}
895
896static int check_cert(X509_STORE_CTX *ctx)
897{
898 X509_CRL *crl = NULL, *dcrl = NULL;
899 int ok = 0;
900 int cnum = ctx->error_depth;
901 X509 *x = sk_X509_value(ctx->chain, cnum);
902
903 ctx->current_cert = x;
904 ctx->current_issuer = NULL;
905 ctx->current_crl_score = 0;
906 ctx->current_reasons = 0;
907
908 if (x->ex_flags & EXFLAG_PROXY)
909 return 1;
910
911 while (ctx->current_reasons != CRLDP_ALL_REASONS) {
912 unsigned int last_reasons = ctx->current_reasons;
913
914 /* Try to retrieve relevant CRL */
915 if (ctx->get_crl)
916 ok = ctx->get_crl(ctx, &crl, x);
917 else
918 ok = get_crl_delta(ctx, &crl, &dcrl, x);
919 /*
920 * If error looking up CRL, nothing we can do except notify callback
921 */
922 if (!ok) {
923 ok = verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL);
924 goto done;
925 }
926 ctx->current_crl = crl;
927 ok = ctx->check_crl(ctx, crl);
928 if (!ok)
929 goto done;
930
931 if (dcrl) {
932 ok = ctx->check_crl(ctx, dcrl);
933 if (!ok)
934 goto done;
935 ok = ctx->cert_crl(ctx, dcrl, x);
936 if (!ok)
937 goto done;
938 } else
939 ok = 1;
940
941 /* Don't look in full CRL if delta reason is removefromCRL */
942 if (ok != 2) {
943 ok = ctx->cert_crl(ctx, crl, x);
944 if (!ok)
945 goto done;
946 }
947
948 X509_CRL_free(crl);
949 X509_CRL_free(dcrl);
950 crl = NULL;
951 dcrl = NULL;
952 /*
953 * If reasons not updated we won't get anywhere by another iteration,
954 * so exit loop.
955 */
956 if (last_reasons == ctx->current_reasons) {
957 ok = verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL);
958 goto done;
959 }
960 }
961 done:
962 X509_CRL_free(crl);
963 X509_CRL_free(dcrl);
964
965 ctx->current_crl = NULL;
966 return ok;
967}
968
969/* Check CRL times against values in X509_STORE_CTX */
970
971static int check_crl_time(X509_STORE_CTX *ctx, X509_CRL *crl, int notify)
972{
973 time_t *ptime;
974 int i;
975
976 if (notify)
977 ctx->current_crl = crl;
978 if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME)
979 ptime = &ctx->param->check_time;
980 else if (ctx->param->flags & X509_V_FLAG_NO_CHECK_TIME)
981 return 1;
982 else
983 ptime = NULL;
984
985 i = X509_cmp_time(X509_CRL_get0_lastUpdate(crl), ptime);
986 if (i == 0) {
987 if (!notify)
988 return 0;
989 if (!verify_cb_crl(ctx, X509_V_ERR_ERROR_IN_CRL_LAST_UPDATE_FIELD))
990 return 0;
991 }
992
993 if (i > 0) {
994 if (!notify)
995 return 0;
996 if (!verify_cb_crl(ctx, X509_V_ERR_CRL_NOT_YET_VALID))
997 return 0;
998 }
999
1000 if (X509_CRL_get0_nextUpdate(crl)) {
1001 i = X509_cmp_time(X509_CRL_get0_nextUpdate(crl), ptime);
1002
1003 if (i == 0) {
1004 if (!notify)
1005 return 0;
1006 if (!verify_cb_crl(ctx, X509_V_ERR_ERROR_IN_CRL_NEXT_UPDATE_FIELD))
1007 return 0;
1008 }
1009 /* Ignore expiry of base CRL is delta is valid */
1010 if ((i < 0) && !(ctx->current_crl_score & CRL_SCORE_TIME_DELTA)) {
1011 if (!notify)
1012 return 0;
1013 if (!verify_cb_crl(ctx, X509_V_ERR_CRL_HAS_EXPIRED))
1014 return 0;
1015 }
1016 }
1017
1018 if (notify)
1019 ctx->current_crl = NULL;
1020
1021 return 1;
1022}
1023
1024static int get_crl_sk(X509_STORE_CTX *ctx, X509_CRL **pcrl, X509_CRL **pdcrl,
1025 X509 **pissuer, int *pscore, unsigned int *preasons,
1026 STACK_OF(X509_CRL) *crls)
1027{
1028 int i, crl_score, best_score = *pscore;
1029 unsigned int reasons, best_reasons = 0;
1030 X509 *x = ctx->current_cert;
1031 X509_CRL *crl, *best_crl = NULL;
1032 X509 *crl_issuer = NULL, *best_crl_issuer = NULL;
1033
1034 for (i = 0; i < sk_X509_CRL_num(crls); i++) {
1035 crl = sk_X509_CRL_value(crls, i);
1036 reasons = *preasons;
1037 crl_score = get_crl_score(ctx, &crl_issuer, &reasons, crl, x);
1038 if (crl_score < best_score || crl_score == 0)
1039 continue;
1040 /* If current CRL is equivalent use it if it is newer */
1041 if (crl_score == best_score && best_crl != NULL) {
1042 int day, sec;
1043 if (ASN1_TIME_diff(&day, &sec, X509_CRL_get0_lastUpdate(best_crl),
1044 X509_CRL_get0_lastUpdate(crl)) == 0)
1045 continue;
1046 /*
1047 * ASN1_TIME_diff never returns inconsistent signs for |day|
1048 * and |sec|.
1049 */
1050 if (day <= 0 && sec <= 0)
1051 continue;
1052 }
1053 best_crl = crl;
1054 best_crl_issuer = crl_issuer;
1055 best_score = crl_score;
1056 best_reasons = reasons;
1057 }
1058
1059 if (best_crl) {
1060 X509_CRL_free(*pcrl);
1061 *pcrl = best_crl;
1062 *pissuer = best_crl_issuer;
1063 *pscore = best_score;
1064 *preasons = best_reasons;
1065 X509_CRL_up_ref(best_crl);
1066 X509_CRL_free(*pdcrl);
1067 *pdcrl = NULL;
1068 get_delta_sk(ctx, pdcrl, pscore, best_crl, crls);
1069 }
1070
1071 if (best_score >= CRL_SCORE_VALID)
1072 return 1;
1073
1074 return 0;
1075}
1076
1077/*
1078 * Compare two CRL extensions for delta checking purposes. They should be
1079 * both present or both absent. If both present all fields must be identical.
1080 */
1081
1082static int crl_extension_match(X509_CRL *a, X509_CRL *b, int nid)
1083{
1084 ASN1_OCTET_STRING *exta, *extb;
1085 int i;
1086 i = X509_CRL_get_ext_by_NID(a, nid, -1);
1087 if (i >= 0) {
1088 /* Can't have multiple occurrences */
1089 if (X509_CRL_get_ext_by_NID(a, nid, i) != -1)
1090 return 0;
1091 exta = X509_EXTENSION_get_data(X509_CRL_get_ext(a, i));
1092 } else
1093 exta = NULL;
1094
1095 i = X509_CRL_get_ext_by_NID(b, nid, -1);
1096
1097 if (i >= 0) {
1098
1099 if (X509_CRL_get_ext_by_NID(b, nid, i) != -1)
1100 return 0;
1101 extb = X509_EXTENSION_get_data(X509_CRL_get_ext(b, i));
1102 } else
1103 extb = NULL;
1104
1105 if (!exta && !extb)
1106 return 1;
1107
1108 if (!exta || !extb)
1109 return 0;
1110
1111 if (ASN1_OCTET_STRING_cmp(exta, extb))
1112 return 0;
1113
1114 return 1;
1115}
1116
1117/* See if a base and delta are compatible */
1118
1119static int check_delta_base(X509_CRL *delta, X509_CRL *base)
1120{
1121 /* Delta CRL must be a delta */
1122 if (!delta->base_crl_number)
1123 return 0;
1124 /* Base must have a CRL number */
1125 if (!base->crl_number)
1126 return 0;
1127 /* Issuer names must match */
1128 if (X509_NAME_cmp(X509_CRL_get_issuer(base), X509_CRL_get_issuer(delta)))
1129 return 0;
1130 /* AKID and IDP must match */
1131 if (!crl_extension_match(delta, base, NID_authority_key_identifier))
1132 return 0;
1133 if (!crl_extension_match(delta, base, NID_issuing_distribution_point))
1134 return 0;
1135 /* Delta CRL base number must not exceed Full CRL number. */
1136 if (ASN1_INTEGER_cmp(delta->base_crl_number, base->crl_number) > 0)
1137 return 0;
1138 /* Delta CRL number must exceed full CRL number */
1139 if (ASN1_INTEGER_cmp(delta->crl_number, base->crl_number) > 0)
1140 return 1;
1141 return 0;
1142}
1143
1144/*
1145 * For a given base CRL find a delta... maybe extend to delta scoring or
1146 * retrieve a chain of deltas...
1147 */
1148
1149static void get_delta_sk(X509_STORE_CTX *ctx, X509_CRL **dcrl, int *pscore,
1150 X509_CRL *base, STACK_OF(X509_CRL) *crls)
1151{
1152 X509_CRL *delta;
1153 int i;
1154 if (!(ctx->param->flags & X509_V_FLAG_USE_DELTAS))
1155 return;
1156 if (!((ctx->current_cert->ex_flags | base->flags) & EXFLAG_FRESHEST))
1157 return;
1158 for (i = 0; i < sk_X509_CRL_num(crls); i++) {
1159 delta = sk_X509_CRL_value(crls, i);
1160 if (check_delta_base(delta, base)) {
1161 if (check_crl_time(ctx, delta, 0))
1162 *pscore |= CRL_SCORE_TIME_DELTA;
1163 X509_CRL_up_ref(delta);
1164 *dcrl = delta;
1165 return;
1166 }
1167 }
1168 *dcrl = NULL;
1169}
1170
1171/*
1172 * For a given CRL return how suitable it is for the supplied certificate
1173 * 'x'. The return value is a mask of several criteria. If the issuer is not
1174 * the certificate issuer this is returned in *pissuer. The reasons mask is
1175 * also used to determine if the CRL is suitable: if no new reasons the CRL
1176 * is rejected, otherwise reasons is updated.
1177 */
1178
1179static int get_crl_score(X509_STORE_CTX *ctx, X509 **pissuer,
1180 unsigned int *preasons, X509_CRL *crl, X509 *x)
1181{
1182
1183 int crl_score = 0;
1184 unsigned int tmp_reasons = *preasons, crl_reasons;
1185
1186 /* First see if we can reject CRL straight away */
1187
1188 /* Invalid IDP cannot be processed */
1189 if (crl->idp_flags & IDP_INVALID)
1190 return 0;
1191 /* Reason codes or indirect CRLs need extended CRL support */
1192 if (!(ctx->param->flags & X509_V_FLAG_EXTENDED_CRL_SUPPORT)) {
1193 if (crl->idp_flags & (IDP_INDIRECT | IDP_REASONS))
1194 return 0;
1195 } else if (crl->idp_flags & IDP_REASONS) {
1196 /* If no new reasons reject */
1197 if (!(crl->idp_reasons & ~tmp_reasons))
1198 return 0;
1199 }
1200 /* Don't process deltas at this stage */
1201 else if (crl->base_crl_number)
1202 return 0;
1203 /* If issuer name doesn't match certificate need indirect CRL */
1204 if (X509_NAME_cmp(X509_get_issuer_name(x), X509_CRL_get_issuer(crl))) {
1205 if (!(crl->idp_flags & IDP_INDIRECT))
1206 return 0;
1207 } else
1208 crl_score |= CRL_SCORE_ISSUER_NAME;
1209
1210 if (!(crl->flags & EXFLAG_CRITICAL))
1211 crl_score |= CRL_SCORE_NOCRITICAL;
1212
1213 /* Check expiry */
1214 if (check_crl_time(ctx, crl, 0))
1215 crl_score |= CRL_SCORE_TIME;
1216
1217 /* Check authority key ID and locate certificate issuer */
1218 crl_akid_check(ctx, crl, pissuer, &crl_score);
1219
1220 /* If we can't locate certificate issuer at this point forget it */
1221
1222 if (!(crl_score & CRL_SCORE_AKID))
1223 return 0;
1224
1225 /* Check cert for matching CRL distribution points */
1226
1227 if (crl_crldp_check(x, crl, crl_score, &crl_reasons)) {
1228 /* If no new reasons reject */
1229 if (!(crl_reasons & ~tmp_reasons))
1230 return 0;
1231 tmp_reasons |= crl_reasons;
1232 crl_score |= CRL_SCORE_SCOPE;
1233 }
1234
1235 *preasons = tmp_reasons;
1236
1237 return crl_score;
1238
1239}
1240
1241static void crl_akid_check(X509_STORE_CTX *ctx, X509_CRL *crl,
1242 X509 **pissuer, int *pcrl_score)
1243{
1244 X509 *crl_issuer = NULL;
1245 X509_NAME *cnm = X509_CRL_get_issuer(crl);
1246 int cidx = ctx->error_depth;
1247 int i;
1248
1249 if (cidx != sk_X509_num(ctx->chain) - 1)
1250 cidx++;
1251
1252 crl_issuer = sk_X509_value(ctx->chain, cidx);
1253
1254 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1255 if (*pcrl_score & CRL_SCORE_ISSUER_NAME) {
1256 *pcrl_score |= CRL_SCORE_AKID | CRL_SCORE_ISSUER_CERT;
1257 *pissuer = crl_issuer;
1258 return;
1259 }
1260 }
1261
1262 for (cidx++; cidx < sk_X509_num(ctx->chain); cidx++) {
1263 crl_issuer = sk_X509_value(ctx->chain, cidx);
1264 if (X509_NAME_cmp(X509_get_subject_name(crl_issuer), cnm))
1265 continue;
1266 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1267 *pcrl_score |= CRL_SCORE_AKID | CRL_SCORE_SAME_PATH;
1268 *pissuer = crl_issuer;
1269 return;
1270 }
1271 }
1272
1273 /* Anything else needs extended CRL support */
1274
1275 if (!(ctx->param->flags & X509_V_FLAG_EXTENDED_CRL_SUPPORT))
1276 return;
1277
1278 /*
1279 * Otherwise the CRL issuer is not on the path. Look for it in the set of
1280 * untrusted certificates.
1281 */
1282 for (i = 0; i < sk_X509_num(ctx->untrusted); i++) {
1283 crl_issuer = sk_X509_value(ctx->untrusted, i);
1284 if (X509_NAME_cmp(X509_get_subject_name(crl_issuer), cnm))
1285 continue;
1286 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1287 *pissuer = crl_issuer;
1288 *pcrl_score |= CRL_SCORE_AKID;
1289 return;
1290 }
1291 }
1292}
1293
1294/*
1295 * Check the path of a CRL issuer certificate. This creates a new
1296 * X509_STORE_CTX and populates it with most of the parameters from the
1297 * parent. This could be optimised somewhat since a lot of path checking will
1298 * be duplicated by the parent, but this will rarely be used in practice.
1299 */
1300
1301static int check_crl_path(X509_STORE_CTX *ctx, X509 *x)
1302{
1303 X509_STORE_CTX crl_ctx;
1304 int ret;
1305
1306 /* Don't allow recursive CRL path validation */
1307 if (ctx->parent)
1308 return 0;
1309 if (!X509_STORE_CTX_init(&crl_ctx, ctx->ctx, x, ctx->untrusted))
1310 return -1;
1311
1312 crl_ctx.crls = ctx->crls;
1313 /* Copy verify params across */
1314 X509_STORE_CTX_set0_param(&crl_ctx, ctx->param);
1315
1316 crl_ctx.parent = ctx;
1317 crl_ctx.verify_cb = ctx->verify_cb;
1318
1319 /* Verify CRL issuer */
1320 ret = X509_verify_cert(&crl_ctx);
1321 if (ret <= 0)
1322 goto err;
1323
1324 /* Check chain is acceptable */
1325 ret = check_crl_chain(ctx, ctx->chain, crl_ctx.chain);
1326 err:
1327 X509_STORE_CTX_cleanup(&crl_ctx);
1328 return ret;
1329}
1330
1331/*
1332 * RFC3280 says nothing about the relationship between CRL path and
1333 * certificate path, which could lead to situations where a certificate could
1334 * be revoked or validated by a CA not authorised to do so. RFC5280 is more
1335 * strict and states that the two paths must end in the same trust anchor,
1336 * though some discussions remain... until this is resolved we use the
1337 * RFC5280 version
1338 */
1339
1340static int check_crl_chain(X509_STORE_CTX *ctx,
1341 STACK_OF(X509) *cert_path,
1342 STACK_OF(X509) *crl_path)
1343{
1344 X509 *cert_ta, *crl_ta;
1345 cert_ta = sk_X509_value(cert_path, sk_X509_num(cert_path) - 1);
1346 crl_ta = sk_X509_value(crl_path, sk_X509_num(crl_path) - 1);
1347 if (!X509_cmp(cert_ta, crl_ta))
1348 return 1;
1349 return 0;
1350}
1351
1352/*-
1353 * Check for match between two dist point names: three separate cases.
1354 * 1. Both are relative names and compare X509_NAME types.
1355 * 2. One full, one relative. Compare X509_NAME to GENERAL_NAMES.
1356 * 3. Both are full names and compare two GENERAL_NAMES.
1357 * 4. One is NULL: automatic match.
1358 */
1359
1360static int idp_check_dp(DIST_POINT_NAME *a, DIST_POINT_NAME *b)
1361{
1362 X509_NAME *nm = NULL;
1363 GENERAL_NAMES *gens = NULL;
1364 GENERAL_NAME *gena, *genb;
1365 int i, j;
1366 if (!a || !b)
1367 return 1;
1368 if (a->type == 1) {
1369 if (!a->dpname)
1370 return 0;
1371 /* Case 1: two X509_NAME */
1372 if (b->type == 1) {
1373 if (!b->dpname)
1374 return 0;
1375 if (!X509_NAME_cmp(a->dpname, b->dpname))
1376 return 1;
1377 else
1378 return 0;
1379 }
1380 /* Case 2: set name and GENERAL_NAMES appropriately */
1381 nm = a->dpname;
1382 gens = b->name.fullname;
1383 } else if (b->type == 1) {
1384 if (!b->dpname)
1385 return 0;
1386 /* Case 2: set name and GENERAL_NAMES appropriately */
1387 gens = a->name.fullname;
1388 nm = b->dpname;
1389 }
1390
1391 /* Handle case 2 with one GENERAL_NAMES and one X509_NAME */
1392 if (nm) {
1393 for (i = 0; i < sk_GENERAL_NAME_num(gens); i++) {
1394 gena = sk_GENERAL_NAME_value(gens, i);
1395 if (gena->type != GEN_DIRNAME)
1396 continue;
1397 if (!X509_NAME_cmp(nm, gena->d.directoryName))
1398 return 1;
1399 }
1400 return 0;
1401 }
1402
1403 /* Else case 3: two GENERAL_NAMES */
1404
1405 for (i = 0; i < sk_GENERAL_NAME_num(a->name.fullname); i++) {
1406 gena = sk_GENERAL_NAME_value(a->name.fullname, i);
1407 for (j = 0; j < sk_GENERAL_NAME_num(b->name.fullname); j++) {
1408 genb = sk_GENERAL_NAME_value(b->name.fullname, j);
1409 if (!GENERAL_NAME_cmp(gena, genb))
1410 return 1;
1411 }
1412 }
1413
1414 return 0;
1415
1416}
1417
1418static int crldp_check_crlissuer(DIST_POINT *dp, X509_CRL *crl, int crl_score)
1419{
1420 int i;
1421 X509_NAME *nm = X509_CRL_get_issuer(crl);
1422 /* If no CRLissuer return is successful iff don't need a match */
1423 if (!dp->CRLissuer)
1424 return ! !(crl_score & CRL_SCORE_ISSUER_NAME);
1425 for (i = 0; i < sk_GENERAL_NAME_num(dp->CRLissuer); i++) {
1426 GENERAL_NAME *gen = sk_GENERAL_NAME_value(dp->CRLissuer, i);
1427 if (gen->type != GEN_DIRNAME)
1428 continue;
1429 if (!X509_NAME_cmp(gen->d.directoryName, nm))
1430 return 1;
1431 }
1432 return 0;
1433}
1434
1435/* Check CRLDP and IDP */
1436
1437static int crl_crldp_check(X509 *x, X509_CRL *crl, int crl_score,
1438 unsigned int *preasons)
1439{
1440 int i;
1441 if (crl->idp_flags & IDP_ONLYATTR)
1442 return 0;
1443 if (x->ex_flags & EXFLAG_CA) {
1444 if (crl->idp_flags & IDP_ONLYUSER)
1445 return 0;
1446 } else {
1447 if (crl->idp_flags & IDP_ONLYCA)
1448 return 0;
1449 }
1450 *preasons = crl->idp_reasons;
1451 for (i = 0; i < sk_DIST_POINT_num(x->crldp); i++) {
1452 DIST_POINT *dp = sk_DIST_POINT_value(x->crldp, i);
1453 if (crldp_check_crlissuer(dp, crl, crl_score)) {
1454 if (!crl->idp || idp_check_dp(dp->distpoint, crl->idp->distpoint)) {
1455 *preasons &= dp->dp_reasons;
1456 return 1;
1457 }
1458 }
1459 }
1460 if ((!crl->idp || !crl->idp->distpoint)
1461 && (crl_score & CRL_SCORE_ISSUER_NAME))
1462 return 1;
1463 return 0;
1464}
1465
1466/*
1467 * Retrieve CRL corresponding to current certificate. If deltas enabled try
1468 * to find a delta CRL too
1469 */
1470
1471static int get_crl_delta(X509_STORE_CTX *ctx,
1472 X509_CRL **pcrl, X509_CRL **pdcrl, X509 *x)
1473{
1474 int ok;
1475 X509 *issuer = NULL;
1476 int crl_score = 0;
1477 unsigned int reasons;
1478 X509_CRL *crl = NULL, *dcrl = NULL;
1479 STACK_OF(X509_CRL) *skcrl;
1480 X509_NAME *nm = X509_get_issuer_name(x);
1481
1482 reasons = ctx->current_reasons;
1483 ok = get_crl_sk(ctx, &crl, &dcrl,
1484 &issuer, &crl_score, &reasons, ctx->crls);
1485 if (ok)
1486 goto done;
1487
1488 /* Lookup CRLs from store */
1489
1490 skcrl = ctx->lookup_crls(ctx, nm);
1491
1492 /* If no CRLs found and a near match from get_crl_sk use that */
1493 if (!skcrl && crl)
1494 goto done;
1495
1496 get_crl_sk(ctx, &crl, &dcrl, &issuer, &crl_score, &reasons, skcrl);
1497
1498 sk_X509_CRL_pop_free(skcrl, X509_CRL_free);
1499
1500 done:
1501 /* If we got any kind of CRL use it and return success */
1502 if (crl) {
1503 ctx->current_issuer = issuer;
1504 ctx->current_crl_score = crl_score;
1505 ctx->current_reasons = reasons;
1506 *pcrl = crl;
1507 *pdcrl = dcrl;
1508 return 1;
1509 }
1510 return 0;
1511}
1512
1513/* Check CRL validity */
1514static int check_crl(X509_STORE_CTX *ctx, X509_CRL *crl)
1515{
1516 X509 *issuer = NULL;
1517 EVP_PKEY *ikey = NULL;
1518 int cnum = ctx->error_depth;
1519 int chnum = sk_X509_num(ctx->chain) - 1;
1520
1521 /* if we have an alternative CRL issuer cert use that */
1522 if (ctx->current_issuer)
1523 issuer = ctx->current_issuer;
1524 /*
1525 * Else find CRL issuer: if not last certificate then issuer is next
1526 * certificate in chain.
1527 */
1528 else if (cnum < chnum)
1529 issuer = sk_X509_value(ctx->chain, cnum + 1);
1530 else {
1531 issuer = sk_X509_value(ctx->chain, chnum);
1532 /* If not self signed, can't check signature */
1533 if (!ctx->check_issued(ctx, issuer, issuer) &&
1534 !verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL_ISSUER))
1535 return 0;
1536 }
1537
1538 if (issuer == NULL)
1539 return 1;
1540
1541 /*
1542 * Skip most tests for deltas because they have already been done
1543 */
1544 if (!crl->base_crl_number) {
1545 /* Check for cRLSign bit if keyUsage present */
1546 if ((issuer->ex_flags & EXFLAG_KUSAGE) &&
1547 !(issuer->ex_kusage & KU_CRL_SIGN) &&
1548 !verify_cb_crl(ctx, X509_V_ERR_KEYUSAGE_NO_CRL_SIGN))
1549 return 0;
1550
1551 if (!(ctx->current_crl_score & CRL_SCORE_SCOPE) &&
1552 !verify_cb_crl(ctx, X509_V_ERR_DIFFERENT_CRL_SCOPE))
1553 return 0;
1554
1555 if (!(ctx->current_crl_score & CRL_SCORE_SAME_PATH) &&
1556 check_crl_path(ctx, ctx->current_issuer) <= 0 &&
1557 !verify_cb_crl(ctx, X509_V_ERR_CRL_PATH_VALIDATION_ERROR))
1558 return 0;
1559
1560 if ((crl->idp_flags & IDP_INVALID) &&
1561 !verify_cb_crl(ctx, X509_V_ERR_INVALID_EXTENSION))
1562 return 0;
1563 }
1564
1565 if (!(ctx->current_crl_score & CRL_SCORE_TIME) &&
1566 !check_crl_time(ctx, crl, 1))
1567 return 0;
1568
1569 /* Attempt to get issuer certificate public key */
1570 ikey = X509_get0_pubkey(issuer);
1571
1572 if (!ikey &&
1573 !verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY))
1574 return 0;
1575
1576 if (ikey) {
1577 int rv = X509_CRL_check_suiteb(crl, ikey, ctx->param->flags);
1578
1579 if (rv != X509_V_OK && !verify_cb_crl(ctx, rv))
1580 return 0;
1581 /* Verify CRL signature */
1582 if (X509_CRL_verify(crl, ikey) <= 0 &&
1583 !verify_cb_crl(ctx, X509_V_ERR_CRL_SIGNATURE_FAILURE))
1584 return 0;
1585 }
1586 return 1;
1587}
1588
1589/* Check certificate against CRL */
1590static int cert_crl(X509_STORE_CTX *ctx, X509_CRL *crl, X509 *x)
1591{
1592 X509_REVOKED *rev;
1593
1594 /*
1595 * The rules changed for this... previously if a CRL contained unhandled
1596 * critical extensions it could still be used to indicate a certificate
1597 * was revoked. This has since been changed since critical extensions can
1598 * change the meaning of CRL entries.
1599 */
1600 if (!(ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL)
1601 && (crl->flags & EXFLAG_CRITICAL) &&
1602 !verify_cb_crl(ctx, X509_V_ERR_UNHANDLED_CRITICAL_CRL_EXTENSION))
1603 return 0;
1604 /*
1605 * Look for serial number of certificate in CRL. If found, make sure
1606 * reason is not removeFromCRL.
1607 */
1608 if (X509_CRL_get0_by_cert(crl, &rev, x)) {
1609 if (rev->reason == CRL_REASON_REMOVE_FROM_CRL)
1610 return 2;
1611 if (!verify_cb_crl(ctx, X509_V_ERR_CERT_REVOKED))
1612 return 0;
1613 }
1614
1615 return 1;
1616}
1617
1618static int check_policy(X509_STORE_CTX *ctx)
1619{
1620 int ret;
1621
1622 if (ctx->parent)
1623 return 1;
1624 /*
1625 * With DANE, the trust anchor might be a bare public key, not a
1626 * certificate! In that case our chain does not have the trust anchor
1627 * certificate as a top-most element. This comports well with RFC5280
1628 * chain verification, since there too, the trust anchor is not part of the
1629 * chain to be verified. In particular, X509_policy_check() does not look
1630 * at the TA cert, but assumes that it is present as the top-most chain
1631 * element. We therefore temporarily push a NULL cert onto the chain if it
1632 * was verified via a bare public key, and pop it off right after the
1633 * X509_policy_check() call.
1634 */
1635 if (ctx->bare_ta_signed && !sk_X509_push(ctx->chain, NULL)) {
1636 X509err(X509_F_CHECK_POLICY, ERR_R_MALLOC_FAILURE);
1637 ctx->error = X509_V_ERR_OUT_OF_MEM;
1638 return 0;
1639 }
1640 ret = X509_policy_check(&ctx->tree, &ctx->explicit_policy, ctx->chain,
1641 ctx->param->policies, ctx->param->flags);
1642 if (ctx->bare_ta_signed)
1643 sk_X509_pop(ctx->chain);
1644
1645 if (ret == X509_PCY_TREE_INTERNAL) {
1646 X509err(X509_F_CHECK_POLICY, ERR_R_MALLOC_FAILURE);
1647 ctx->error = X509_V_ERR_OUT_OF_MEM;
1648 return 0;
1649 }
1650 /* Invalid or inconsistent extensions */
1651 if (ret == X509_PCY_TREE_INVALID) {
1652 int i;
1653
1654 /* Locate certificates with bad extensions and notify callback. */
1655 for (i = 1; i < sk_X509_num(ctx->chain); i++) {
1656 X509 *x = sk_X509_value(ctx->chain, i);
1657
1658 if (!(x->ex_flags & EXFLAG_INVALID_POLICY))
1659 continue;
1660 if (!verify_cb_cert(ctx, x, i,
1661 X509_V_ERR_INVALID_POLICY_EXTENSION))
1662 return 0;
1663 }
1664 return 1;
1665 }
1666 if (ret == X509_PCY_TREE_FAILURE) {
1667 ctx->current_cert = NULL;
1668 ctx->error = X509_V_ERR_NO_EXPLICIT_POLICY;
1669 return ctx->verify_cb(0, ctx);
1670 }
1671 if (ret != X509_PCY_TREE_VALID) {
1672 X509err(X509_F_CHECK_POLICY, ERR_R_INTERNAL_ERROR);
1673 return 0;
1674 }
1675
1676 if (ctx->param->flags & X509_V_FLAG_NOTIFY_POLICY) {
1677 ctx->current_cert = NULL;
1678 /*
1679 * Verification errors need to be "sticky", a callback may have allowed
1680 * an SSL handshake to continue despite an error, and we must then
1681 * remain in an error state. Therefore, we MUST NOT clear earlier
1682 * verification errors by setting the error to X509_V_OK.
1683 */
1684 if (!ctx->verify_cb(2, ctx))
1685 return 0;
1686 }
1687
1688 return 1;
1689}
1690
1691/*-
1692 * Check certificate validity times.
1693 * If depth >= 0, invoke verification callbacks on error, otherwise just return
1694 * the validation status.
1695 *
1696 * Return 1 on success, 0 otherwise.
1697 */
1698int x509_check_cert_time(X509_STORE_CTX *ctx, X509 *x, int depth)
1699{
1700 time_t *ptime;
1701 int i;
1702
1703 if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME)
1704 ptime = &ctx->param->check_time;
1705 else if (ctx->param->flags & X509_V_FLAG_NO_CHECK_TIME)
1706 return 1;
1707 else
1708 ptime = NULL;
1709
1710 i = X509_cmp_time(X509_get0_notBefore(x), ptime);
1711 if (i >= 0 && depth < 0)
1712 return 0;
1713 if (i == 0 && !verify_cb_cert(ctx, x, depth,
1714 X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD))
1715 return 0;
1716 if (i > 0 && !verify_cb_cert(ctx, x, depth, X509_V_ERR_CERT_NOT_YET_VALID))
1717 return 0;
1718
1719 i = X509_cmp_time(X509_get0_notAfter(x), ptime);
1720 if (i <= 0 && depth < 0)
1721 return 0;
1722 if (i == 0 && !verify_cb_cert(ctx, x, depth,
1723 X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD))
1724 return 0;
1725 if (i < 0 && !verify_cb_cert(ctx, x, depth, X509_V_ERR_CERT_HAS_EXPIRED))
1726 return 0;
1727 return 1;
1728}
1729
1730/* verify the issuer signatures and cert times of ctx->chain */
1731static int internal_verify(X509_STORE_CTX *ctx)
1732{
1733 int n = sk_X509_num(ctx->chain) - 1;
1734 X509 *xi = sk_X509_value(ctx->chain, n);
1735 X509 *xs;
1736
1737 /*
1738 * With DANE-verified bare public key TA signatures, it remains only to
1739 * check the timestamps of the top certificate. We report the issuer as
1740 * NULL, since all we have is a bare key.
1741 */
1742 if (ctx->bare_ta_signed) {
1743 xs = xi;
1744 xi = NULL;
1745 goto check_cert_time;
1746 }
1747
1748 if (ctx->check_issued(ctx, xi, xi))
1749 xs = xi; /* the typical case: last cert in the chain is self-issued */
1750 else {
1751 if (ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) {
1752 xs = xi;
1753 goto check_cert_time;
1754 }
1755 if (n <= 0) {
1756 if (!verify_cb_cert(ctx, xi, 0,
1757 X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE))
1758 return 0;
1759
1760 xs = xi;
1761 goto check_cert_time;
1762 }
1763
1764 n--;
1765 ctx->error_depth = n;
1766 xs = sk_X509_value(ctx->chain, n);
1767 }
1768
1769 /*
1770 * Do not clear ctx->error=0, it must be "sticky", only the user's callback
1771 * is allowed to reset errors (at its own peril).
1772 */
1773 while (n >= 0) {
1774 /*
1775 * For each iteration of this loop:
1776 * n is the subject depth
1777 * xs is the subject cert, for which the signature is to be checked
1778 * xi is the supposed issuer cert containing the public key to use
1779 * Initially xs == xi if the last cert in the chain is self-issued.
1780 *
1781 * Skip signature check for self-signed certificates unless explicitly
1782 * asked for because it does not add any security and just wastes time.
1783 */
1784 if (xs != xi || ((ctx->param->flags & X509_V_FLAG_CHECK_SS_SIGNATURE)
1785 && (xi->ex_flags & EXFLAG_SS) != 0)) {
1786 EVP_PKEY *pkey;
1787 /*
1788 * If the issuer's public key is not available or its key usage
1789 * does not support issuing the subject cert, report the issuer
1790 * cert and its depth (rather than n, the depth of the subject).
1791 */
1792 int issuer_depth = n + (xs == xi ? 0 : 1);
1793 /*
1794 * According to https://tools.ietf.org/html/rfc5280#section-6.1.4
1795 * step (n) we must check any given key usage extension in a CA cert
1796 * when preparing the verification of a certificate issued by it.
1797 * According to https://tools.ietf.org/html/rfc5280#section-4.2.1.3
1798 * we must not verify a certifiate signature if the key usage of the
1799 * CA certificate that issued the certificate prohibits signing.
1800 * In case the 'issuing' certificate is the last in the chain and is
1801 * not a CA certificate but a 'self-issued' end-entity cert (i.e.,
1802 * xs == xi && !(xi->ex_flags & EXFLAG_CA)) RFC 5280 does not apply
1803 * (see https://tools.ietf.org/html/rfc6818#section-2) and thus
1804 * we are free to ignore any key usage restrictions on such certs.
1805 */
1806 int ret = xs == xi && (xi->ex_flags & EXFLAG_CA) == 0
1807 ? X509_V_OK : x509_signing_allowed(xi, xs);
1808
1809 if (ret != X509_V_OK && !verify_cb_cert(ctx, xi, issuer_depth, ret))
1810 return 0;
1811 if ((pkey = X509_get0_pubkey(xi)) == NULL) {
1812 ret = X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY;
1813 if (!verify_cb_cert(ctx, xi, issuer_depth, ret))
1814 return 0;
1815 } else if (X509_verify(xs, pkey) <= 0) {
1816 ret = X509_V_ERR_CERT_SIGNATURE_FAILURE;
1817 if (!verify_cb_cert(ctx, xs, n, ret))
1818 return 0;
1819 }
1820 }
1821
1822 check_cert_time: /* in addition to RFC 5280, do also for trusted (root) cert */
1823 /* Calls verify callback as needed */
1824 if (!x509_check_cert_time(ctx, xs, n))
1825 return 0;
1826
1827 /*
1828 * Signal success at this depth. However, the previous error (if any)
1829 * is retained.
1830 */
1831 ctx->current_issuer = xi;
1832 ctx->current_cert = xs;
1833 ctx->error_depth = n;
1834 if (!ctx->verify_cb(1, ctx))
1835 return 0;
1836
1837 if (--n >= 0) {
1838 xi = xs;
1839 xs = sk_X509_value(ctx->chain, n);
1840 }
1841 }
1842 return 1;
1843}
1844
1845int X509_cmp_current_time(const ASN1_TIME *ctm)
1846{
1847 return X509_cmp_time(ctm, NULL);
1848}
1849
1850int X509_cmp_time(const ASN1_TIME *ctm, time_t *cmp_time)
1851{
1852 static const size_t utctime_length = sizeof("YYMMDDHHMMSSZ") - 1;
1853 static const size_t generalizedtime_length = sizeof("YYYYMMDDHHMMSSZ") - 1;
1854 ASN1_TIME *asn1_cmp_time = NULL;
1855 int i, day, sec, ret = 0;
1856#ifdef CHARSET_EBCDIC
1857 const char upper_z = 0x5A;
1858#else
1859 const char upper_z = 'Z';
1860#endif
1861 /*
1862 * Note that ASN.1 allows much more slack in the time format than RFC5280.
1863 * In RFC5280, the representation is fixed:
1864 * UTCTime: YYMMDDHHMMSSZ
1865 * GeneralizedTime: YYYYMMDDHHMMSSZ
1866 *
1867 * We do NOT currently enforce the following RFC 5280 requirement:
1868 * "CAs conforming to this profile MUST always encode certificate
1869 * validity dates through the year 2049 as UTCTime; certificate validity
1870 * dates in 2050 or later MUST be encoded as GeneralizedTime."
1871 */
1872 switch (ctm->type) {
1873 case V_ASN1_UTCTIME:
1874 if (ctm->length != (int)(utctime_length))
1875 return 0;
1876 break;
1877 case V_ASN1_GENERALIZEDTIME:
1878 if (ctm->length != (int)(generalizedtime_length))
1879 return 0;
1880 break;
1881 default:
1882 return 0;
1883 }
1884
1885 /**
1886 * Verify the format: the ASN.1 functions we use below allow a more
1887 * flexible format than what's mandated by RFC 5280.
1888 * Digit and date ranges will be verified in the conversion methods.
1889 */
1890 for (i = 0; i < ctm->length - 1; i++) {
1891 if (!ascii_isdigit(ctm->data[i]))
1892 return 0;
1893 }
1894 if (ctm->data[ctm->length - 1] != upper_z)
1895 return 0;
1896
1897 /*
1898 * There is ASN1_UTCTIME_cmp_time_t but no
1899 * ASN1_GENERALIZEDTIME_cmp_time_t or ASN1_TIME_cmp_time_t,
1900 * so we go through ASN.1
1901 */
1902 asn1_cmp_time = X509_time_adj(NULL, 0, cmp_time);
1903 if (asn1_cmp_time == NULL)
1904 goto err;
1905 if (!ASN1_TIME_diff(&day, &sec, ctm, asn1_cmp_time))
1906 goto err;
1907
1908 /*
1909 * X509_cmp_time comparison is <=.
1910 * The return value 0 is reserved for errors.
1911 */
1912 ret = (day >= 0 && sec >= 0) ? -1 : 1;
1913
1914 err:
1915 ASN1_TIME_free(asn1_cmp_time);
1916 return ret;
1917}
1918
1919ASN1_TIME *X509_gmtime_adj(ASN1_TIME *s, long adj)
1920{
1921 return X509_time_adj(s, adj, NULL);
1922}
1923
1924ASN1_TIME *X509_time_adj(ASN1_TIME *s, long offset_sec, time_t *in_tm)
1925{
1926 return X509_time_adj_ex(s, 0, offset_sec, in_tm);
1927}
1928
1929ASN1_TIME *X509_time_adj_ex(ASN1_TIME *s,
1930 int offset_day, long offset_sec, time_t *in_tm)
1931{
1932 time_t t;
1933
1934 if (in_tm)
1935 t = *in_tm;
1936 else
1937 time(&t);
1938
1939 if (s && !(s->flags & ASN1_STRING_FLAG_MSTRING)) {
1940 if (s->type == V_ASN1_UTCTIME)
1941 return ASN1_UTCTIME_adj(s, t, offset_day, offset_sec);
1942 if (s->type == V_ASN1_GENERALIZEDTIME)
1943 return ASN1_GENERALIZEDTIME_adj(s, t, offset_day, offset_sec);
1944 }
1945 return ASN1_TIME_adj(s, t, offset_day, offset_sec);
1946}
1947
1948int X509_get_pubkey_parameters(EVP_PKEY *pkey, STACK_OF(X509) *chain)
1949{
1950 EVP_PKEY *ktmp = NULL, *ktmp2;
1951 int i, j;
1952
1953 if ((pkey != NULL) && !EVP_PKEY_missing_parameters(pkey))
1954 return 1;
1955
1956 for (i = 0; i < sk_X509_num(chain); i++) {
1957 ktmp = X509_get0_pubkey(sk_X509_value(chain, i));
1958 if (ktmp == NULL) {
1959 X509err(X509_F_X509_GET_PUBKEY_PARAMETERS,
1960 X509_R_UNABLE_TO_GET_CERTS_PUBLIC_KEY);
1961 return 0;
1962 }
1963 if (!EVP_PKEY_missing_parameters(ktmp))
1964 break;
1965 }
1966 if (ktmp == NULL) {
1967 X509err(X509_F_X509_GET_PUBKEY_PARAMETERS,
1968 X509_R_UNABLE_TO_FIND_PARAMETERS_IN_CHAIN);
1969 return 0;
1970 }
1971
1972 /* first, populate the other certs */
1973 for (j = i - 1; j >= 0; j--) {
1974 ktmp2 = X509_get0_pubkey(sk_X509_value(chain, j));
1975 EVP_PKEY_copy_parameters(ktmp2, ktmp);
1976 }
1977
1978 if (pkey != NULL)
1979 EVP_PKEY_copy_parameters(pkey, ktmp);
1980 return 1;
1981}
1982
1983/* Make a delta CRL as the diff between two full CRLs */
1984
1985X509_CRL *X509_CRL_diff(X509_CRL *base, X509_CRL *newer,
1986 EVP_PKEY *skey, const EVP_MD *md, unsigned int flags)
1987{
1988 X509_CRL *crl = NULL;
1989 int i;
1990 STACK_OF(X509_REVOKED) *revs = NULL;
1991 /* CRLs can't be delta already */
1992 if (base->base_crl_number || newer->base_crl_number) {
1993 X509err(X509_F_X509_CRL_DIFF, X509_R_CRL_ALREADY_DELTA);
1994 return NULL;
1995 }
1996 /* Base and new CRL must have a CRL number */
1997 if (!base->crl_number || !newer->crl_number) {
1998 X509err(X509_F_X509_CRL_DIFF, X509_R_NO_CRL_NUMBER);
1999 return NULL;
2000 }
2001 /* Issuer names must match */
2002 if (X509_NAME_cmp(X509_CRL_get_issuer(base), X509_CRL_get_issuer(newer))) {
2003 X509err(X509_F_X509_CRL_DIFF, X509_R_ISSUER_MISMATCH);
2004 return NULL;
2005 }
2006 /* AKID and IDP must match */
2007 if (!crl_extension_match(base, newer, NID_authority_key_identifier)) {
2008 X509err(X509_F_X509_CRL_DIFF, X509_R_AKID_MISMATCH);
2009 return NULL;
2010 }
2011 if (!crl_extension_match(base, newer, NID_issuing_distribution_point)) {
2012 X509err(X509_F_X509_CRL_DIFF, X509_R_IDP_MISMATCH);
2013 return NULL;
2014 }
2015 /* Newer CRL number must exceed full CRL number */
2016 if (ASN1_INTEGER_cmp(newer->crl_number, base->crl_number) <= 0) {
2017 X509err(X509_F_X509_CRL_DIFF, X509_R_NEWER_CRL_NOT_NEWER);
2018 return NULL;
2019 }
2020 /* CRLs must verify */
2021 if (skey && (X509_CRL_verify(base, skey) <= 0 ||
2022 X509_CRL_verify(newer, skey) <= 0)) {
2023 X509err(X509_F_X509_CRL_DIFF, X509_R_CRL_VERIFY_FAILURE);
2024 return NULL;
2025 }
2026 /* Create new CRL */
2027 crl = X509_CRL_new();
2028 if (crl == NULL || !X509_CRL_set_version(crl, 1))
2029 goto memerr;
2030 /* Set issuer name */
2031 if (!X509_CRL_set_issuer_name(crl, X509_CRL_get_issuer(newer)))
2032 goto memerr;
2033
2034 if (!X509_CRL_set1_lastUpdate(crl, X509_CRL_get0_lastUpdate(newer)))
2035 goto memerr;
2036 if (!X509_CRL_set1_nextUpdate(crl, X509_CRL_get0_nextUpdate(newer)))
2037 goto memerr;
2038
2039 /* Set base CRL number: must be critical */
2040
2041 if (!X509_CRL_add1_ext_i2d(crl, NID_delta_crl, base->crl_number, 1, 0))
2042 goto memerr;
2043
2044 /*
2045 * Copy extensions across from newest CRL to delta: this will set CRL
2046 * number to correct value too.
2047 */
2048
2049 for (i = 0; i < X509_CRL_get_ext_count(newer); i++) {
2050 X509_EXTENSION *ext;
2051 ext = X509_CRL_get_ext(newer, i);
2052 if (!X509_CRL_add_ext(crl, ext, -1))
2053 goto memerr;
2054 }
2055
2056 /* Go through revoked entries, copying as needed */
2057
2058 revs = X509_CRL_get_REVOKED(newer);
2059
2060 for (i = 0; i < sk_X509_REVOKED_num(revs); i++) {
2061 X509_REVOKED *rvn, *rvtmp;
2062 rvn = sk_X509_REVOKED_value(revs, i);
2063 /*
2064 * Add only if not also in base. TODO: need something cleverer here
2065 * for some more complex CRLs covering multiple CAs.
2066 */
2067 if (!X509_CRL_get0_by_serial(base, &rvtmp, &rvn->serialNumber)) {
2068 rvtmp = X509_REVOKED_dup(rvn);
2069 if (!rvtmp)
2070 goto memerr;
2071 if (!X509_CRL_add0_revoked(crl, rvtmp)) {
2072 X509_REVOKED_free(rvtmp);
2073 goto memerr;
2074 }
2075 }
2076 }
2077 /* TODO: optionally prune deleted entries */
2078
2079 if (skey && md && !X509_CRL_sign(crl, skey, md))
2080 goto memerr;
2081
2082 return crl;
2083
2084 memerr:
2085 X509err(X509_F_X509_CRL_DIFF, ERR_R_MALLOC_FAILURE);
2086 X509_CRL_free(crl);
2087 return NULL;
2088}
2089
2090int X509_STORE_CTX_set_ex_data(X509_STORE_CTX *ctx, int idx, void *data)
2091{
2092 return CRYPTO_set_ex_data(&ctx->ex_data, idx, data);
2093}
2094
2095void *X509_STORE_CTX_get_ex_data(X509_STORE_CTX *ctx, int idx)
2096{
2097 return CRYPTO_get_ex_data(&ctx->ex_data, idx);
2098}
2099
2100int X509_STORE_CTX_get_error(X509_STORE_CTX *ctx)
2101{
2102 return ctx->error;
2103}
2104
2105void X509_STORE_CTX_set_error(X509_STORE_CTX *ctx, int err)
2106{
2107 ctx->error = err;
2108}
2109
2110int X509_STORE_CTX_get_error_depth(X509_STORE_CTX *ctx)
2111{
2112 return ctx->error_depth;
2113}
2114
2115void X509_STORE_CTX_set_error_depth(X509_STORE_CTX *ctx, int depth)
2116{
2117 ctx->error_depth = depth;
2118}
2119
2120X509 *X509_STORE_CTX_get_current_cert(X509_STORE_CTX *ctx)
2121{
2122 return ctx->current_cert;
2123}
2124
2125void X509_STORE_CTX_set_current_cert(X509_STORE_CTX *ctx, X509 *x)
2126{
2127 ctx->current_cert = x;
2128}
2129
2130STACK_OF(X509) *X509_STORE_CTX_get0_chain(X509_STORE_CTX *ctx)
2131{
2132 return ctx->chain;
2133}
2134
2135STACK_OF(X509) *X509_STORE_CTX_get1_chain(X509_STORE_CTX *ctx)
2136{
2137 if (!ctx->chain)
2138 return NULL;
2139 return X509_chain_up_ref(ctx->chain);
2140}
2141
2142X509 *X509_STORE_CTX_get0_current_issuer(X509_STORE_CTX *ctx)
2143{
2144 return ctx->current_issuer;
2145}
2146
2147X509_CRL *X509_STORE_CTX_get0_current_crl(X509_STORE_CTX *ctx)
2148{
2149 return ctx->current_crl;
2150}
2151
2152X509_STORE_CTX *X509_STORE_CTX_get0_parent_ctx(X509_STORE_CTX *ctx)
2153{
2154 return ctx->parent;
2155}
2156
2157void X509_STORE_CTX_set_cert(X509_STORE_CTX *ctx, X509 *x)
2158{
2159 ctx->cert = x;
2160}
2161
2162void X509_STORE_CTX_set0_crls(X509_STORE_CTX *ctx, STACK_OF(X509_CRL) *sk)
2163{
2164 ctx->crls = sk;
2165}
2166
2167int X509_STORE_CTX_set_purpose(X509_STORE_CTX *ctx, int purpose)
2168{
2169 /*
2170 * XXX: Why isn't this function always used to set the associated trust?
2171 * Should there even be a VPM->trust field at all? Or should the trust
2172 * always be inferred from the purpose by X509_STORE_CTX_init().
2173 */
2174 return X509_STORE_CTX_purpose_inherit(ctx, 0, purpose, 0);
2175}
2176
2177int X509_STORE_CTX_set_trust(X509_STORE_CTX *ctx, int trust)
2178{
2179 /*
2180 * XXX: See above, this function would only be needed when the default
2181 * trust for the purpose needs an override in a corner case.
2182 */
2183 return X509_STORE_CTX_purpose_inherit(ctx, 0, 0, trust);
2184}
2185
2186/*
2187 * This function is used to set the X509_STORE_CTX purpose and trust values.
2188 * This is intended to be used when another structure has its own trust and
2189 * purpose values which (if set) will be inherited by the ctx. If they aren't
2190 * set then we will usually have a default purpose in mind which should then
2191 * be used to set the trust value. An example of this is SSL use: an SSL
2192 * structure will have its own purpose and trust settings which the
2193 * application can set: if they aren't set then we use the default of SSL
2194 * client/server.
2195 */
2196
2197int X509_STORE_CTX_purpose_inherit(X509_STORE_CTX *ctx, int def_purpose,
2198 int purpose, int trust)
2199{
2200 int idx;
2201 /* If purpose not set use default */
2202 if (!purpose)
2203 purpose = def_purpose;
2204 /*
2205 * If purpose is set but we don't have a default then set the default to
2206 * the current purpose
2207 */
2208 else if (def_purpose == 0)
2209 def_purpose = purpose;
2210 /* If we have a purpose then check it is valid */
2211 if (purpose) {
2212 X509_PURPOSE *ptmp;
2213 idx = X509_PURPOSE_get_by_id(purpose);
2214 if (idx == -1) {
2215 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2216 X509_R_UNKNOWN_PURPOSE_ID);
2217 return 0;
2218 }
2219 ptmp = X509_PURPOSE_get0(idx);
2220 if (ptmp->trust == X509_TRUST_DEFAULT) {
2221 idx = X509_PURPOSE_get_by_id(def_purpose);
2222 if (idx == -1) {
2223 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2224 X509_R_UNKNOWN_PURPOSE_ID);
2225 return 0;
2226 }
2227 ptmp = X509_PURPOSE_get0(idx);
2228 }
2229 /* If trust not set then get from purpose default */
2230 if (!trust)
2231 trust = ptmp->trust;
2232 }
2233 if (trust) {
2234 idx = X509_TRUST_get_by_id(trust);
2235 if (idx == -1) {
2236 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2237 X509_R_UNKNOWN_TRUST_ID);
2238 return 0;
2239 }
2240 }
2241
2242 if (purpose && !ctx->param->purpose)
2243 ctx->param->purpose = purpose;
2244 if (trust && !ctx->param->trust)
2245 ctx->param->trust = trust;
2246 return 1;
2247}
2248
2249X509_STORE_CTX *X509_STORE_CTX_new(void)
2250{
2251 X509_STORE_CTX *ctx = OPENSSL_zalloc(sizeof(*ctx));
2252
2253 if (ctx == NULL) {
2254 X509err(X509_F_X509_STORE_CTX_NEW, ERR_R_MALLOC_FAILURE);
2255 return NULL;
2256 }
2257 return ctx;
2258}
2259
2260void X509_STORE_CTX_free(X509_STORE_CTX *ctx)
2261{
2262 if (ctx == NULL)
2263 return;
2264
2265 X509_STORE_CTX_cleanup(ctx);
2266 OPENSSL_free(ctx);
2267}
2268
2269int X509_STORE_CTX_init(X509_STORE_CTX *ctx, X509_STORE *store, X509 *x509,
2270 STACK_OF(X509) *chain)
2271{
2272 int ret = 1;
2273
2274 ctx->ctx = store;
2275 ctx->cert = x509;
2276 ctx->untrusted = chain;
2277 ctx->crls = NULL;
2278 ctx->num_untrusted = 0;
2279 ctx->other_ctx = NULL;
2280 ctx->valid = 0;
2281 ctx->chain = NULL;
2282 ctx->error = 0;
2283 ctx->explicit_policy = 0;
2284 ctx->error_depth = 0;
2285 ctx->current_cert = NULL;
2286 ctx->current_issuer = NULL;
2287 ctx->current_crl = NULL;
2288 ctx->current_crl_score = 0;
2289 ctx->current_reasons = 0;
2290 ctx->tree = NULL;
2291 ctx->parent = NULL;
2292 ctx->dane = NULL;
2293 ctx->bare_ta_signed = 0;
2294 /* Zero ex_data to make sure we're cleanup-safe */
2295 memset(&ctx->ex_data, 0, sizeof(ctx->ex_data));
2296
2297 /* store->cleanup is always 0 in OpenSSL, if set must be idempotent */
2298 if (store)
2299 ctx->cleanup = store->cleanup;
2300 else
2301 ctx->cleanup = 0;
2302
2303 if (store && store->check_issued)
2304 ctx->check_issued = store->check_issued;
2305 else
2306 ctx->check_issued = check_issued;
2307
2308 if (store && store->get_issuer)
2309 ctx->get_issuer = store->get_issuer;
2310 else
2311 ctx->get_issuer = X509_STORE_CTX_get1_issuer;
2312
2313 if (store && store->verify_cb)
2314 ctx->verify_cb = store->verify_cb;
2315 else
2316 ctx->verify_cb = null_callback;
2317
2318 if (store && store->verify)
2319 ctx->verify = store->verify;
2320 else
2321 ctx->verify = internal_verify;
2322
2323 if (store && store->check_revocation)
2324 ctx->check_revocation = store->check_revocation;
2325 else
2326 ctx->check_revocation = check_revocation;
2327
2328 if (store && store->get_crl)
2329 ctx->get_crl = store->get_crl;
2330 else
2331 ctx->get_crl = NULL;
2332
2333 if (store && store->check_crl)
2334 ctx->check_crl = store->check_crl;
2335 else
2336 ctx->check_crl = check_crl;
2337
2338 if (store && store->cert_crl)
2339 ctx->cert_crl = store->cert_crl;
2340 else
2341 ctx->cert_crl = cert_crl;
2342
2343 if (store && store->check_policy)
2344 ctx->check_policy = store->check_policy;
2345 else
2346 ctx->check_policy = check_policy;
2347
2348 if (store && store->lookup_certs)
2349 ctx->lookup_certs = store->lookup_certs;
2350 else
2351 ctx->lookup_certs = X509_STORE_CTX_get1_certs;
2352
2353 if (store && store->lookup_crls)
2354 ctx->lookup_crls = store->lookup_crls;
2355 else
2356 ctx->lookup_crls = X509_STORE_CTX_get1_crls;
2357
2358 ctx->param = X509_VERIFY_PARAM_new();
2359 if (ctx->param == NULL) {
2360 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2361 goto err;
2362 }
2363
2364 /*
2365 * Inherit callbacks and flags from X509_STORE if not set use defaults.
2366 */
2367 if (store)
2368 ret = X509_VERIFY_PARAM_inherit(ctx->param, store->param);
2369 else
2370 ctx->param->inh_flags |= X509_VP_FLAG_DEFAULT | X509_VP_FLAG_ONCE;
2371
2372 if (ret)
2373 ret = X509_VERIFY_PARAM_inherit(ctx->param,
2374 X509_VERIFY_PARAM_lookup("default"));
2375
2376 if (ret == 0) {
2377 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2378 goto err;
2379 }
2380
2381 /*
2382 * XXX: For now, continue to inherit trust from VPM, but infer from the
2383 * purpose if this still yields the default value.
2384 */
2385 if (ctx->param->trust == X509_TRUST_DEFAULT) {
2386 int idx = X509_PURPOSE_get_by_id(ctx->param->purpose);
2387 X509_PURPOSE *xp = X509_PURPOSE_get0(idx);
2388
2389 if (xp != NULL)
2390 ctx->param->trust = X509_PURPOSE_get_trust(xp);
2391 }
2392
2393 if (CRYPTO_new_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx,
2394 &ctx->ex_data))
2395 return 1;
2396 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2397
2398 err:
2399 /*
2400 * On error clean up allocated storage, if the store context was not
2401 * allocated with X509_STORE_CTX_new() this is our last chance to do so.
2402 */
2403 X509_STORE_CTX_cleanup(ctx);
2404 return 0;
2405}
2406
2407/*
2408 * Set alternative lookup method: just a STACK of trusted certificates. This
2409 * avoids X509_STORE nastiness where it isn't needed.
2410 */
2411void X509_STORE_CTX_set0_trusted_stack(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2412{
2413 ctx->other_ctx = sk;
2414 ctx->get_issuer = get_issuer_sk;
2415 ctx->lookup_certs = lookup_certs_sk;
2416}
2417
2418void X509_STORE_CTX_cleanup(X509_STORE_CTX *ctx)
2419{
2420 /*
2421 * We need to be idempotent because, unfortunately, free() also calls
2422 * cleanup(), so the natural call sequence new(), init(), cleanup(), free()
2423 * calls cleanup() for the same object twice! Thus we must zero the
2424 * pointers below after they're freed!
2425 */
2426 /* Seems to always be 0 in OpenSSL, do this at most once. */
2427 if (ctx->cleanup != NULL) {
2428 ctx->cleanup(ctx);
2429 ctx->cleanup = NULL;
2430 }
2431 if (ctx->param != NULL) {
2432 if (ctx->parent == NULL)
2433 X509_VERIFY_PARAM_free(ctx->param);
2434 ctx->param = NULL;
2435 }
2436 X509_policy_tree_free(ctx->tree);
2437 ctx->tree = NULL;
2438 sk_X509_pop_free(ctx->chain, X509_free);
2439 ctx->chain = NULL;
2440 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx, &(ctx->ex_data));
2441 memset(&ctx->ex_data, 0, sizeof(ctx->ex_data));
2442}
2443
2444void X509_STORE_CTX_set_depth(X509_STORE_CTX *ctx, int depth)
2445{
2446 X509_VERIFY_PARAM_set_depth(ctx->param, depth);
2447}
2448
2449void X509_STORE_CTX_set_flags(X509_STORE_CTX *ctx, unsigned long flags)
2450{
2451 X509_VERIFY_PARAM_set_flags(ctx->param, flags);
2452}
2453
2454void X509_STORE_CTX_set_time(X509_STORE_CTX *ctx, unsigned long flags,
2455 time_t t)
2456{
2457 X509_VERIFY_PARAM_set_time(ctx->param, t);
2458}
2459
2460X509 *X509_STORE_CTX_get0_cert(X509_STORE_CTX *ctx)
2461{
2462 return ctx->cert;
2463}
2464
2465STACK_OF(X509) *X509_STORE_CTX_get0_untrusted(X509_STORE_CTX *ctx)
2466{
2467 return ctx->untrusted;
2468}
2469
2470void X509_STORE_CTX_set0_untrusted(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2471{
2472 ctx->untrusted = sk;
2473}
2474
2475void X509_STORE_CTX_set0_verified_chain(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2476{
2477 sk_X509_pop_free(ctx->chain, X509_free);
2478 ctx->chain = sk;
2479}
2480
2481void X509_STORE_CTX_set_verify_cb(X509_STORE_CTX *ctx,
2482 X509_STORE_CTX_verify_cb verify_cb)
2483{
2484 ctx->verify_cb = verify_cb;
2485}
2486
2487X509_STORE_CTX_verify_cb X509_STORE_CTX_get_verify_cb(X509_STORE_CTX *ctx)
2488{
2489 return ctx->verify_cb;
2490}
2491
2492void X509_STORE_CTX_set_verify(X509_STORE_CTX *ctx,
2493 X509_STORE_CTX_verify_fn verify)
2494{
2495 ctx->verify = verify;
2496}
2497
2498X509_STORE_CTX_verify_fn X509_STORE_CTX_get_verify(X509_STORE_CTX *ctx)
2499{
2500 return ctx->verify;
2501}
2502
2503X509_STORE_CTX_get_issuer_fn X509_STORE_CTX_get_get_issuer(X509_STORE_CTX *ctx)
2504{
2505 return ctx->get_issuer;
2506}
2507
2508X509_STORE_CTX_check_issued_fn X509_STORE_CTX_get_check_issued(X509_STORE_CTX *ctx)
2509{
2510 return ctx->check_issued;
2511}
2512
2513X509_STORE_CTX_check_revocation_fn X509_STORE_CTX_get_check_revocation(X509_STORE_CTX *ctx)
2514{
2515 return ctx->check_revocation;
2516}
2517
2518X509_STORE_CTX_get_crl_fn X509_STORE_CTX_get_get_crl(X509_STORE_CTX *ctx)
2519{
2520 return ctx->get_crl;
2521}
2522
2523X509_STORE_CTX_check_crl_fn X509_STORE_CTX_get_check_crl(X509_STORE_CTX *ctx)
2524{
2525 return ctx->check_crl;
2526}
2527
2528X509_STORE_CTX_cert_crl_fn X509_STORE_CTX_get_cert_crl(X509_STORE_CTX *ctx)
2529{
2530 return ctx->cert_crl;
2531}
2532
2533X509_STORE_CTX_check_policy_fn X509_STORE_CTX_get_check_policy(X509_STORE_CTX *ctx)
2534{
2535 return ctx->check_policy;
2536}
2537
2538X509_STORE_CTX_lookup_certs_fn X509_STORE_CTX_get_lookup_certs(X509_STORE_CTX *ctx)
2539{
2540 return ctx->lookup_certs;
2541}
2542
2543X509_STORE_CTX_lookup_crls_fn X509_STORE_CTX_get_lookup_crls(X509_STORE_CTX *ctx)
2544{
2545 return ctx->lookup_crls;
2546}
2547
2548X509_STORE_CTX_cleanup_fn X509_STORE_CTX_get_cleanup(X509_STORE_CTX *ctx)
2549{
2550 return ctx->cleanup;
2551}
2552
2553X509_POLICY_TREE *X509_STORE_CTX_get0_policy_tree(X509_STORE_CTX *ctx)
2554{
2555 return ctx->tree;
2556}
2557
2558int X509_STORE_CTX_get_explicit_policy(X509_STORE_CTX *ctx)
2559{
2560 return ctx->explicit_policy;
2561}
2562
2563int X509_STORE_CTX_get_num_untrusted(X509_STORE_CTX *ctx)
2564{
2565 return ctx->num_untrusted;
2566}
2567
2568int X509_STORE_CTX_set_default(X509_STORE_CTX *ctx, const char *name)
2569{
2570 const X509_VERIFY_PARAM *param;
2571 param = X509_VERIFY_PARAM_lookup(name);
2572 if (!param)
2573 return 0;
2574 return X509_VERIFY_PARAM_inherit(ctx->param, param);
2575}
2576
2577X509_VERIFY_PARAM *X509_STORE_CTX_get0_param(X509_STORE_CTX *ctx)
2578{
2579 return ctx->param;
2580}
2581
2582void X509_STORE_CTX_set0_param(X509_STORE_CTX *ctx, X509_VERIFY_PARAM *param)
2583{
2584 X509_VERIFY_PARAM_free(ctx->param);
2585 ctx->param = param;
2586}
2587
2588void X509_STORE_CTX_set0_dane(X509_STORE_CTX *ctx, SSL_DANE *dane)
2589{
2590 ctx->dane = dane;
2591}
2592
2593static unsigned char *dane_i2d(
2594 X509 *cert,
2595 uint8_t selector,
2596 unsigned int *i2dlen)
2597{
2598 unsigned char *buf = NULL;
2599 int len;
2600
2601 /*
2602 * Extract ASN.1 DER form of certificate or public key.
2603 */
2604 switch (selector) {
2605 case DANETLS_SELECTOR_CERT:
2606 len = i2d_X509(cert, &buf);
2607 break;
2608 case DANETLS_SELECTOR_SPKI:
2609 len = i2d_X509_PUBKEY(X509_get_X509_PUBKEY(cert), &buf);
2610 break;
2611 default:
2612 X509err(X509_F_DANE_I2D, X509_R_BAD_SELECTOR);
2613 return NULL;
2614 }
2615
2616 if (len < 0 || buf == NULL) {
2617 X509err(X509_F_DANE_I2D, ERR_R_MALLOC_FAILURE);
2618 return NULL;
2619 }
2620
2621 *i2dlen = (unsigned int)len;
2622 return buf;
2623}
2624
2625#define DANETLS_NONE 256 /* impossible uint8_t */
2626
2627static int dane_match(X509_STORE_CTX *ctx, X509 *cert, int depth)
2628{
2629 SSL_DANE *dane = ctx->dane;
2630 unsigned usage = DANETLS_NONE;
2631 unsigned selector = DANETLS_NONE;
2632 unsigned ordinal = DANETLS_NONE;
2633 unsigned mtype = DANETLS_NONE;
2634 unsigned char *i2dbuf = NULL;
2635 unsigned int i2dlen = 0;
2636 unsigned char mdbuf[EVP_MAX_MD_SIZE];
2637 unsigned char *cmpbuf = NULL;
2638 unsigned int cmplen = 0;
2639 int i;
2640 int recnum;
2641 int matched = 0;
2642 danetls_record *t = NULL;
2643 uint32_t mask;
2644
2645 mask = (depth == 0) ? DANETLS_EE_MASK : DANETLS_TA_MASK;
2646
2647 /*
2648 * The trust store is not applicable with DANE-TA(2)
2649 */
2650 if (depth >= ctx->num_untrusted)
2651 mask &= DANETLS_PKIX_MASK;
2652
2653 /*
2654 * If we've previously matched a PKIX-?? record, no need to test any
2655 * further PKIX-?? records, it remains to just build the PKIX chain.
2656 * Had the match been a DANE-?? record, we'd be done already.
2657 */
2658 if (dane->mdpth >= 0)
2659 mask &= ~DANETLS_PKIX_MASK;
2660
2661 /*-
2662 * https://tools.ietf.org/html/rfc7671#section-5.1
2663 * https://tools.ietf.org/html/rfc7671#section-5.2
2664 * https://tools.ietf.org/html/rfc7671#section-5.3
2665 * https://tools.ietf.org/html/rfc7671#section-5.4
2666 *
2667 * We handle DANE-EE(3) records first as they require no chain building
2668 * and no expiration or hostname checks. We also process digests with
2669 * higher ordinals first and ignore lower priorities except Full(0) which
2670 * is always processed (last). If none match, we then process PKIX-EE(1).
2671 *
2672 * NOTE: This relies on DANE usages sorting before the corresponding PKIX
2673 * usages in SSL_dane_tlsa_add(), and also on descending sorting of digest
2674 * priorities. See twin comment in ssl/ssl_lib.c.
2675 *
2676 * We expect that most TLSA RRsets will have just a single usage, so we
2677 * don't go out of our way to cache multiple selector-specific i2d buffers
2678 * across usages, but if the selector happens to remain the same as switch
2679 * usages, that's OK. Thus, a set of "3 1 1", "3 0 1", "1 1 1", "1 0 1",
2680 * records would result in us generating each of the certificate and public
2681 * key DER forms twice, but more typically we'd just see multiple "3 1 1"
2682 * or multiple "3 0 1" records.
2683 *
2684 * As soon as we find a match at any given depth, we stop, because either
2685 * we've matched a DANE-?? record and the peer is authenticated, or, after
2686 * exhausting all DANE-?? records, we've matched a PKIX-?? record, which is
2687 * sufficient for DANE, and what remains to do is ordinary PKIX validation.
2688 */
2689 recnum = (dane->umask & mask) ? sk_danetls_record_num(dane->trecs) : 0;
2690 for (i = 0; matched == 0 && i < recnum; ++i) {
2691 t = sk_danetls_record_value(dane->trecs, i);
2692 if ((DANETLS_USAGE_BIT(t->usage) & mask) == 0)
2693 continue;
2694 if (t->usage != usage) {
2695 usage = t->usage;
2696
2697 /* Reset digest agility for each usage/selector pair */
2698 mtype = DANETLS_NONE;
2699 ordinal = dane->dctx->mdord[t->mtype];
2700 }
2701 if (t->selector != selector) {
2702 selector = t->selector;
2703
2704 /* Update per-selector state */
2705 OPENSSL_free(i2dbuf);
2706 i2dbuf = dane_i2d(cert, selector, &i2dlen);
2707 if (i2dbuf == NULL)
2708 return -1;
2709
2710 /* Reset digest agility for each usage/selector pair */
2711 mtype = DANETLS_NONE;
2712 ordinal = dane->dctx->mdord[t->mtype];
2713 } else if (t->mtype != DANETLS_MATCHING_FULL) {
2714 /*-
2715 * Digest agility:
2716 *
2717 * <https://tools.ietf.org/html/rfc7671#section-9>
2718 *
2719 * For a fixed selector, after processing all records with the
2720 * highest mtype ordinal, ignore all mtypes with lower ordinals
2721 * other than "Full".
2722 */
2723 if (dane->dctx->mdord[t->mtype] < ordinal)
2724 continue;
2725 }
2726
2727 /*
2728 * Each time we hit a (new selector or) mtype, re-compute the relevant
2729 * digest, more complex caching is not worth the code space.
2730 */
2731 if (t->mtype != mtype) {
2732 const EVP_MD *md = dane->dctx->mdevp[mtype = t->mtype];
2733 cmpbuf = i2dbuf;
2734 cmplen = i2dlen;
2735
2736 if (md != NULL) {
2737 cmpbuf = mdbuf;
2738 if (!EVP_Digest(i2dbuf, i2dlen, cmpbuf, &cmplen, md, 0)) {
2739 matched = -1;
2740 break;
2741 }
2742 }
2743 }
2744
2745 /*
2746 * Squirrel away the certificate and depth if we have a match. Any
2747 * DANE match is dispositive, but with PKIX we still need to build a
2748 * full chain.
2749 */
2750 if (cmplen == t->dlen &&
2751 memcmp(cmpbuf, t->data, cmplen) == 0) {
2752 if (DANETLS_USAGE_BIT(usage) & DANETLS_DANE_MASK)
2753 matched = 1;
2754 if (matched || dane->mdpth < 0) {
2755 dane->mdpth = depth;
2756 dane->mtlsa = t;
2757 OPENSSL_free(dane->mcert);
2758 dane->mcert = cert;
2759 X509_up_ref(cert);
2760 }
2761 break;
2762 }
2763 }
2764
2765 /* Clear the one-element DER cache */
2766 OPENSSL_free(i2dbuf);
2767 return matched;
2768}
2769
2770static int check_dane_issuer(X509_STORE_CTX *ctx, int depth)
2771{
2772 SSL_DANE *dane = ctx->dane;
2773 int matched = 0;
2774 X509 *cert;
2775
2776 if (!DANETLS_HAS_TA(dane) || depth == 0)
2777 return X509_TRUST_UNTRUSTED;
2778
2779 /*
2780 * Record any DANE trust-anchor matches, for the first depth to test, if
2781 * there's one at that depth. (This'll be false for length 1 chains looking
2782 * for an exact match for the leaf certificate).
2783 */
2784 cert = sk_X509_value(ctx->chain, depth);
2785 if (cert != NULL && (matched = dane_match(ctx, cert, depth)) < 0)
2786 return X509_TRUST_REJECTED;
2787 if (matched > 0) {
2788 ctx->num_untrusted = depth - 1;
2789 return X509_TRUST_TRUSTED;
2790 }
2791
2792 return X509_TRUST_UNTRUSTED;
2793}
2794
2795static int check_dane_pkeys(X509_STORE_CTX *ctx)
2796{
2797 SSL_DANE *dane = ctx->dane;
2798 danetls_record *t;
2799 int num = ctx->num_untrusted;
2800 X509 *cert = sk_X509_value(ctx->chain, num - 1);
2801 int recnum = sk_danetls_record_num(dane->trecs);
2802 int i;
2803
2804 for (i = 0; i < recnum; ++i) {
2805 t = sk_danetls_record_value(dane->trecs, i);
2806 if (t->usage != DANETLS_USAGE_DANE_TA ||
2807 t->selector != DANETLS_SELECTOR_SPKI ||
2808 t->mtype != DANETLS_MATCHING_FULL ||
2809 X509_verify(cert, t->spki) <= 0)
2810 continue;
2811
2812 /* Clear any PKIX-?? matches that failed to extend to a full chain */
2813 X509_free(dane->mcert);
2814 dane->mcert = NULL;
2815
2816 /* Record match via a bare TA public key */
2817 ctx->bare_ta_signed = 1;
2818 dane->mdpth = num - 1;
2819 dane->mtlsa = t;
2820
2821 /* Prune any excess chain certificates */
2822 num = sk_X509_num(ctx->chain);
2823 for (; num > ctx->num_untrusted; --num)
2824 X509_free(sk_X509_pop(ctx->chain));
2825
2826 return X509_TRUST_TRUSTED;
2827 }
2828
2829 return X509_TRUST_UNTRUSTED;
2830}
2831
2832static void dane_reset(SSL_DANE *dane)
2833{
2834 /*
2835 * Reset state to verify another chain, or clear after failure.
2836 */
2837 X509_free(dane->mcert);
2838 dane->mcert = NULL;
2839 dane->mtlsa = NULL;
2840 dane->mdpth = -1;
2841 dane->pdpth = -1;
2842}
2843
2844static int check_leaf_suiteb(X509_STORE_CTX *ctx, X509 *cert)
2845{
2846 int err = X509_chain_check_suiteb(NULL, cert, NULL, ctx->param->flags);
2847
2848 if (err == X509_V_OK)
2849 return 1;
2850 return verify_cb_cert(ctx, cert, 0, err);
2851}
2852
2853static int dane_verify(X509_STORE_CTX *ctx)
2854{
2855 X509 *cert = ctx->cert;
2856 SSL_DANE *dane = ctx->dane;
2857 int matched;
2858 int done;
2859
2860 dane_reset(dane);
2861
2862 /*-
2863 * When testing the leaf certificate, if we match a DANE-EE(3) record,
2864 * dane_match() returns 1 and we're done. If however we match a PKIX-EE(1)
2865 * record, the match depth and matching TLSA record are recorded, but the
2866 * return value is 0, because we still need to find a PKIX trust-anchor.
2867 * Therefore, when DANE authentication is enabled (required), we're done
2868 * if:
2869 * + matched < 0, internal error.
2870 * + matched == 1, we matched a DANE-EE(3) record
2871 * + matched == 0, mdepth < 0 (no PKIX-EE match) and there are no
2872 * DANE-TA(2) or PKIX-TA(0) to test.
2873 */
2874 matched = dane_match(ctx, ctx->cert, 0);
2875 done = matched != 0 || (!DANETLS_HAS_TA(dane) && dane->mdpth < 0);
2876
2877 if (done)
2878 X509_get_pubkey_parameters(NULL, ctx->chain);
2879
2880 if (matched > 0) {
2881 /* Callback invoked as needed */
2882 if (!check_leaf_suiteb(ctx, cert))
2883 return 0;
2884 /* Callback invoked as needed */
2885 if ((dane->flags & DANE_FLAG_NO_DANE_EE_NAMECHECKS) == 0 &&
2886 !check_id(ctx))
2887 return 0;
2888 /* Bypass internal_verify(), issue depth 0 success callback */
2889 ctx->error_depth = 0;
2890 ctx->current_cert = cert;
2891 return ctx->verify_cb(1, ctx);
2892 }
2893
2894 if (matched < 0) {
2895 ctx->error_depth = 0;
2896 ctx->current_cert = cert;
2897 ctx->error = X509_V_ERR_OUT_OF_MEM;
2898 return -1;
2899 }
2900
2901 if (done) {
2902 /* Fail early, TA-based success is not possible */
2903 if (!check_leaf_suiteb(ctx, cert))
2904 return 0;
2905 return verify_cb_cert(ctx, cert, 0, X509_V_ERR_DANE_NO_MATCH);
2906 }
2907
2908 /*
2909 * Chain verification for usages 0/1/2. TLSA record matching of depth > 0
2910 * certificates happens in-line with building the rest of the chain.
2911 */
2912 return verify_chain(ctx);
2913}
2914
2915/* Get issuer, without duplicate suppression */
2916static int get_issuer(X509 **issuer, X509_STORE_CTX *ctx, X509 *cert)
2917{
2918 STACK_OF(X509) *saved_chain = ctx->chain;
2919 int ok;
2920
2921 ctx->chain = NULL;
2922 ok = ctx->get_issuer(issuer, ctx, cert);
2923 ctx->chain = saved_chain;
2924
2925 return ok;
2926}
2927
2928static int augment_stack(STACK_OF(X509) *src, STACK_OF(X509) **dstPtr)
2929{
2930 if (src) {
2931 STACK_OF(X509) *dst;
2932 int i;
2933
2934 if (*dstPtr == NULL)
2935 return ((*dstPtr = sk_X509_dup(src)) != NULL);
2936
2937 for (dst = *dstPtr, i = 0; i < sk_X509_num(src); ++i) {
2938 if (!sk_X509_push(dst, sk_X509_value(src, i))) {
2939 sk_X509_free(dst);
2940 *dstPtr = NULL;
2941 return 0;
2942 }
2943 }
2944 }
2945 return 1;
2946}
2947
2948static int build_chain(X509_STORE_CTX *ctx)
2949{
2950 SSL_DANE *dane = ctx->dane;
2951 int num = sk_X509_num(ctx->chain);
2952 X509 *cert = sk_X509_value(ctx->chain, num - 1);
2953 int ss = cert_self_signed(cert);
2954 STACK_OF(X509) *sktmp = NULL;
2955 unsigned int search;
2956 int may_trusted = 0;
2957 int may_alternate = 0;
2958 int trust = X509_TRUST_UNTRUSTED;
2959 int alt_untrusted = 0;
2960 int depth;
2961 int ok = 0;
2962 int i;
2963
2964 /* Our chain starts with a single untrusted element. */
2965 if (!ossl_assert(num == 1 && ctx->num_untrusted == num)) {
2966 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
2967 ctx->error = X509_V_ERR_UNSPECIFIED;
2968 return 0;
2969 }
2970
2971#define S_DOUNTRUSTED (1 << 0) /* Search untrusted chain */
2972#define S_DOTRUSTED (1 << 1) /* Search trusted store */
2973#define S_DOALTERNATE (1 << 2) /* Retry with pruned alternate chain */
2974 /*
2975 * Set up search policy, untrusted if possible, trusted-first if enabled.
2976 * If we're doing DANE and not doing PKIX-TA/PKIX-EE, we never look in the
2977 * trust_store, otherwise we might look there first. If not trusted-first,
2978 * and alternate chains are not disabled, try building an alternate chain
2979 * if no luck with untrusted first.
2980 */
2981 search = (ctx->untrusted != NULL) ? S_DOUNTRUSTED : 0;
2982 if (DANETLS_HAS_PKIX(dane) || !DANETLS_HAS_DANE(dane)) {
2983 if (search == 0 || ctx->param->flags & X509_V_FLAG_TRUSTED_FIRST)
2984 search |= S_DOTRUSTED;
2985 else if (!(ctx->param->flags & X509_V_FLAG_NO_ALT_CHAINS))
2986 may_alternate = 1;
2987 may_trusted = 1;
2988 }
2989
2990 /*
2991 * If we got any "Cert(0) Full(0)" issuer certificates from DNS, *prepend*
2992 * them to our working copy of the untrusted certificate stack. Since the
2993 * caller of X509_STORE_CTX_init() may have provided only a leaf cert with
2994 * no corresponding stack of untrusted certificates, we may need to create
2995 * an empty stack first. [ At present only the ssl library provides DANE
2996 * support, and ssl_verify_cert_chain() always provides a non-null stack
2997 * containing at least the leaf certificate, but we must be prepared for
2998 * this to change. ]
2999 */
3000 if (DANETLS_ENABLED(dane) && !augment_stack(dane->certs, &sktmp)) {
3001 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
3002 ctx->error = X509_V_ERR_OUT_OF_MEM;
3003 return 0;
3004 }
3005
3006 /*
3007 * Shallow-copy the stack of untrusted certificates (with TLS, this is
3008 * typically the content of the peer's certificate message) so can make
3009 * multiple passes over it, while free to remove elements as we go.
3010 */
3011 if (!augment_stack(ctx->untrusted, &sktmp)) {
3012 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
3013 ctx->error = X509_V_ERR_OUT_OF_MEM;
3014 return 0;
3015 }
3016
3017 /*
3018 * Still absurdly large, but arithmetically safe, a lower hard upper bound
3019 * might be reasonable.
3020 */
3021 if (ctx->param->depth > INT_MAX/2)
3022 ctx->param->depth = INT_MAX/2;
3023
3024 /*
3025 * Try to Extend the chain until we reach an ultimately trusted issuer.
3026 * Build chains up to one longer the limit, later fail if we hit the limit,
3027 * with an X509_V_ERR_CERT_CHAIN_TOO_LONG error code.
3028 */
3029 depth = ctx->param->depth + 1;
3030
3031 while (search != 0) {
3032 X509 *x;
3033 X509 *xtmp = NULL;
3034
3035 /*
3036 * Look in the trust store if enabled for first lookup, or we've run
3037 * out of untrusted issuers and search here is not disabled. When we
3038 * reach the depth limit, we stop extending the chain, if by that point
3039 * we've not found a trust-anchor, any trusted chain would be too long.
3040 *
3041 * The error reported to the application verify callback is at the
3042 * maximal valid depth with the current certificate equal to the last
3043 * not ultimately-trusted issuer. For example, with verify_depth = 0,
3044 * the callback will report errors at depth=1 when the immediate issuer
3045 * of the leaf certificate is not a trust anchor. No attempt will be
3046 * made to locate an issuer for that certificate, since such a chain
3047 * would be a-priori too long.
3048 */
3049 if ((search & S_DOTRUSTED) != 0) {
3050 i = num = sk_X509_num(ctx->chain);
3051 if ((search & S_DOALTERNATE) != 0) {
3052 /*
3053 * As high up the chain as we can, look for an alternative
3054 * trusted issuer of an untrusted certificate that currently
3055 * has an untrusted issuer. We use the alt_untrusted variable
3056 * to track how far up the chain we find the first match. It
3057 * is only if and when we find a match, that we prune the chain
3058 * and reset ctx->num_untrusted to the reduced count of
3059 * untrusted certificates. While we're searching for such a
3060 * match (which may never be found), it is neither safe nor
3061 * wise to preemptively modify either the chain or
3062 * ctx->num_untrusted.
3063 *
3064 * Note, like ctx->num_untrusted, alt_untrusted is a count of
3065 * untrusted certificates, not a "depth".
3066 */
3067 i = alt_untrusted;
3068 }
3069 x = sk_X509_value(ctx->chain, i-1);
3070
3071 ok = (depth < num) ? 0 : get_issuer(&xtmp, ctx, x);
3072
3073 if (ok < 0) {
3074 trust = X509_TRUST_REJECTED;
3075 ctx->error = X509_V_ERR_STORE_LOOKUP;
3076 search = 0;
3077 continue;
3078 }
3079
3080 if (ok > 0) {
3081 /*
3082 * Alternative trusted issuer for a mid-chain untrusted cert?
3083 * Pop the untrusted cert's successors and retry. We might now
3084 * be able to complete a valid chain via the trust store. Note
3085 * that despite the current trust-store match we might still
3086 * fail complete the chain to a suitable trust-anchor, in which
3087 * case we may prune some more untrusted certificates and try
3088 * again. Thus the S_DOALTERNATE bit may yet be turned on
3089 * again with an even shorter untrusted chain!
3090 *
3091 * If in the process we threw away our matching PKIX-TA trust
3092 * anchor, reset DANE trust. We might find a suitable trusted
3093 * certificate among the ones from the trust store.
3094 */
3095 if ((search & S_DOALTERNATE) != 0) {
3096 if (!ossl_assert(num > i && i > 0 && ss == 0)) {
3097 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
3098 X509_free(xtmp);
3099 trust = X509_TRUST_REJECTED;
3100 ctx->error = X509_V_ERR_UNSPECIFIED;
3101 search = 0;
3102 continue;
3103 }
3104 search &= ~S_DOALTERNATE;
3105 for (; num > i; --num)
3106 X509_free(sk_X509_pop(ctx->chain));
3107 ctx->num_untrusted = num;
3108
3109 if (DANETLS_ENABLED(dane) &&
3110 dane->mdpth >= ctx->num_untrusted) {
3111 dane->mdpth = -1;
3112 X509_free(dane->mcert);
3113 dane->mcert = NULL;
3114 }
3115 if (DANETLS_ENABLED(dane) &&
3116 dane->pdpth >= ctx->num_untrusted)
3117 dane->pdpth = -1;
3118 }
3119
3120 /*
3121 * Self-signed untrusted certificates get replaced by their
3122 * trusted matching issuer. Otherwise, grow the chain.
3123 */
3124 if (ss == 0) {
3125 if (!sk_X509_push(ctx->chain, x = xtmp)) {
3126 X509_free(xtmp);
3127 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
3128 trust = X509_TRUST_REJECTED;
3129 ctx->error = X509_V_ERR_OUT_OF_MEM;
3130 search = 0;
3131 continue;
3132 }
3133 ss = cert_self_signed(x);
3134 } else if (num == ctx->num_untrusted) {
3135 /*
3136 * We have a self-signed certificate that has the same
3137 * subject name (and perhaps keyid and/or serial number) as
3138 * a trust-anchor. We must have an exact match to avoid
3139 * possible impersonation via key substitution etc.
3140 */
3141 if (X509_cmp(x, xtmp) != 0) {
3142 /* Self-signed untrusted mimic. */
3143 X509_free(xtmp);
3144 ok = 0;
3145 } else {
3146 X509_free(x);
3147 ctx->num_untrusted = --num;
3148 (void) sk_X509_set(ctx->chain, num, x = xtmp);
3149 }
3150 }
3151
3152 /*
3153 * We've added a new trusted certificate to the chain, recheck
3154 * trust. If not done, and not self-signed look deeper.
3155 * Whether or not we're doing "trusted first", we no longer
3156 * look for untrusted certificates from the peer's chain.
3157 *
3158 * At this point ctx->num_trusted and num must reflect the
3159 * correct number of untrusted certificates, since the DANE
3160 * logic in check_trust() depends on distinguishing CAs from
3161 * "the wire" from CAs from the trust store. In particular, the
3162 * certificate at depth "num" should be the new trusted
3163 * certificate with ctx->num_untrusted <= num.
3164 */
3165 if (ok) {
3166 if (!ossl_assert(ctx->num_untrusted <= num)) {
3167 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
3168 trust = X509_TRUST_REJECTED;
3169 ctx->error = X509_V_ERR_UNSPECIFIED;
3170 search = 0;
3171 continue;
3172 }
3173 search &= ~S_DOUNTRUSTED;
3174 switch (trust = check_trust(ctx, num)) {
3175 case X509_TRUST_TRUSTED:
3176 case X509_TRUST_REJECTED:
3177 search = 0;
3178 continue;
3179 }
3180 if (ss == 0)
3181 continue;
3182 }
3183 }
3184
3185 /*
3186 * No dispositive decision, and either self-signed or no match, if
3187 * we were doing untrusted-first, and alt-chains are not disabled,
3188 * do that, by repeatedly losing one untrusted element at a time,
3189 * and trying to extend the shorted chain.
3190 */
3191 if ((search & S_DOUNTRUSTED) == 0) {
3192 /* Continue search for a trusted issuer of a shorter chain? */
3193 if ((search & S_DOALTERNATE) != 0 && --alt_untrusted > 0)
3194 continue;
3195 /* Still no luck and no fallbacks left? */
3196 if (!may_alternate || (search & S_DOALTERNATE) != 0 ||
3197 ctx->num_untrusted < 2)
3198 break;
3199 /* Search for a trusted issuer of a shorter chain */
3200 search |= S_DOALTERNATE;
3201 alt_untrusted = ctx->num_untrusted - 1;
3202 ss = 0;
3203 }
3204 }
3205
3206 /*
3207 * Extend chain with peer-provided certificates
3208 */
3209 if ((search & S_DOUNTRUSTED) != 0) {
3210 num = sk_X509_num(ctx->chain);
3211 if (!ossl_assert(num == ctx->num_untrusted)) {
3212 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
3213 trust = X509_TRUST_REJECTED;
3214 ctx->error = X509_V_ERR_UNSPECIFIED;
3215 search = 0;
3216 continue;
3217 }
3218 x = sk_X509_value(ctx->chain, num-1);
3219
3220 /*
3221 * Once we run out of untrusted issuers, we stop looking for more
3222 * and start looking only in the trust store if enabled.
3223 */
3224 xtmp = (ss || depth < num) ? NULL : find_issuer(ctx, sktmp, x);
3225 if (xtmp == NULL) {
3226 search &= ~S_DOUNTRUSTED;
3227 if (may_trusted)
3228 search |= S_DOTRUSTED;
3229 continue;
3230 }
3231
3232 /* Drop this issuer from future consideration */
3233 (void) sk_X509_delete_ptr(sktmp, xtmp);
3234
3235 if (!X509_up_ref(xtmp)) {
3236 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
3237 trust = X509_TRUST_REJECTED;
3238 ctx->error = X509_V_ERR_UNSPECIFIED;
3239 search = 0;
3240 continue;
3241 }
3242
3243 if (!sk_X509_push(ctx->chain, xtmp)) {
3244 X509_free(xtmp);
3245 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
3246 trust = X509_TRUST_REJECTED;
3247 ctx->error = X509_V_ERR_OUT_OF_MEM;
3248 search = 0;
3249 continue;
3250 }
3251
3252 x = xtmp;
3253 ++ctx->num_untrusted;
3254 ss = cert_self_signed(xtmp);
3255
3256 /*
3257 * Check for DANE-TA trust of the topmost untrusted certificate.
3258 */
3259 switch (trust = check_dane_issuer(ctx, ctx->num_untrusted - 1)) {
3260 case X509_TRUST_TRUSTED:
3261 case X509_TRUST_REJECTED:
3262 search = 0;
3263 continue;
3264 }
3265 }
3266 }
3267 sk_X509_free(sktmp);
3268
3269 /*
3270 * Last chance to make a trusted chain, either bare DANE-TA public-key
3271 * signers, or else direct leaf PKIX trust.
3272 */
3273 num = sk_X509_num(ctx->chain);
3274 if (num <= depth) {
3275 if (trust == X509_TRUST_UNTRUSTED && DANETLS_HAS_DANE_TA(dane))
3276 trust = check_dane_pkeys(ctx);
3277 if (trust == X509_TRUST_UNTRUSTED && num == ctx->num_untrusted)
3278 trust = check_trust(ctx, num);
3279 }
3280
3281 switch (trust) {
3282 case X509_TRUST_TRUSTED:
3283 return 1;
3284 case X509_TRUST_REJECTED:
3285 /* Callback already issued */
3286 return 0;
3287 case X509_TRUST_UNTRUSTED:
3288 default:
3289 num = sk_X509_num(ctx->chain);
3290 if (num > depth)
3291 return verify_cb_cert(ctx, NULL, num-1,
3292 X509_V_ERR_CERT_CHAIN_TOO_LONG);
3293 if (DANETLS_ENABLED(dane) &&
3294 (!DANETLS_HAS_PKIX(dane) || dane->pdpth >= 0))
3295 return verify_cb_cert(ctx, NULL, num-1, X509_V_ERR_DANE_NO_MATCH);
3296 if (ss && sk_X509_num(ctx->chain) == 1)
3297 return verify_cb_cert(ctx, NULL, num-1,
3298 X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT);
3299 if (ss)
3300 return verify_cb_cert(ctx, NULL, num-1,
3301 X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN);
3302 if (ctx->num_untrusted < num)
3303 return verify_cb_cert(ctx, NULL, num-1,
3304 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT);
3305 return verify_cb_cert(ctx, NULL, num-1,
3306 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY);
3307 }
3308}
3309
3310static const int minbits_table[] = { 80, 112, 128, 192, 256 };
3311static const int NUM_AUTH_LEVELS = OSSL_NELEM(minbits_table);
3312
3313/*
3314 * Check whether the public key of ``cert`` meets the security level of
3315 * ``ctx``.
3316 *
3317 * Returns 1 on success, 0 otherwise.
3318 */
3319static int check_key_level(X509_STORE_CTX *ctx, X509 *cert)
3320{
3321 EVP_PKEY *pkey = X509_get0_pubkey(cert);
3322 int level = ctx->param->auth_level;
3323
3324 /*
3325 * At security level zero, return without checking for a supported public
3326 * key type. Some engines support key types not understood outside the
3327 * engine, and we only need to understand the key when enforcing a security
3328 * floor.
3329 */
3330 if (level <= 0)
3331 return 1;
3332
3333 /* Unsupported or malformed keys are not secure */
3334 if (pkey == NULL)
3335 return 0;
3336
3337 if (level > NUM_AUTH_LEVELS)
3338 level = NUM_AUTH_LEVELS;
3339
3340 return EVP_PKEY_security_bits(pkey) >= minbits_table[level - 1];
3341}
3342
3343/*
3344 * Check whether the public key of ``cert`` does not use explicit params
3345 * for an elliptic curve.
3346 *
3347 * Returns 1 on success, 0 if check fails, -1 for other errors.
3348 */
3349static int check_curve(X509 *cert)
3350{
3351#ifndef OPENSSL_NO_EC
3352 EVP_PKEY *pkey = X509_get0_pubkey(cert);
3353
3354 /* Unsupported or malformed key */
3355 if (pkey == NULL)
3356 return -1;
3357
3358 if (EVP_PKEY_id(pkey) == EVP_PKEY_EC) {
3359 int ret;
3360
3361 ret = EC_KEY_decoded_from_explicit_params(EVP_PKEY_get0_EC_KEY(pkey));
3362 return ret < 0 ? ret : !ret;
3363 }
3364#endif
3365
3366 return 1;
3367}
3368
3369/*
3370 * Check whether the signature digest algorithm of ``cert`` meets the security
3371 * level of ``ctx``. Should not be checked for trust anchors (whether
3372 * self-signed or otherwise).
3373 *
3374 * Returns 1 on success, 0 otherwise.
3375 */
3376static int check_sig_level(X509_STORE_CTX *ctx, X509 *cert)
3377{
3378 int secbits = -1;
3379 int level = ctx->param->auth_level;
3380
3381 if (level <= 0)
3382 return 1;
3383 if (level > NUM_AUTH_LEVELS)
3384 level = NUM_AUTH_LEVELS;
3385
3386 if (!X509_get_signature_info(cert, NULL, NULL, &secbits, NULL))
3387 return 0;
3388
3389 return secbits >= minbits_table[level - 1];
3390}