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source: vbox/trunk/src/libs/openssl-1.1.1i/crypto/x509/x509_vfy.c@ 87232

Last change on this file since 87232 was 87083, checked in by vboxsync, 4 years ago

openssl-1.1.1i: Applied and adjusted our OpenSSL changes to 1.1.1i. bugref:9885
File size: 105.8 KB
Line 
1/*
2 * Copyright 1995-2020 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the OpenSSL license (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10#include <stdio.h>
11#include <time.h>
12#include <errno.h>
13#include <limits.h>
14
15#include "crypto/ctype.h"
16#include "internal/cryptlib.h"
17#include <openssl/crypto.h>
18#include <openssl/buffer.h>
19#include <openssl/evp.h>
20#include <openssl/asn1.h>
21#include <openssl/x509.h>
22#include <openssl/x509v3.h>
23#include <openssl/objects.h>
24#include "internal/dane.h"
25#include "crypto/x509.h"
26#include "x509_local.h"
27
28/* CRL score values */
29
30/* No unhandled critical extensions */
31
32#define CRL_SCORE_NOCRITICAL 0x100
33
34/* certificate is within CRL scope */
35
36#define CRL_SCORE_SCOPE 0x080
37
38/* CRL times valid */
39
40#define CRL_SCORE_TIME 0x040
41
42/* Issuer name matches certificate */
43
44#define CRL_SCORE_ISSUER_NAME 0x020
45
46/* If this score or above CRL is probably valid */
47
48#define CRL_SCORE_VALID (CRL_SCORE_NOCRITICAL|CRL_SCORE_TIME|CRL_SCORE_SCOPE)
49
50/* CRL issuer is certificate issuer */
51
52#define CRL_SCORE_ISSUER_CERT 0x018
53
54/* CRL issuer is on certificate path */
55
56#define CRL_SCORE_SAME_PATH 0x008
57
58/* CRL issuer matches CRL AKID */
59
60#define CRL_SCORE_AKID 0x004
61
62/* Have a delta CRL with valid times */
63
64#define CRL_SCORE_TIME_DELTA 0x002
65
66static int build_chain(X509_STORE_CTX *ctx);
67static int verify_chain(X509_STORE_CTX *ctx);
68static int dane_verify(X509_STORE_CTX *ctx);
69static int null_callback(int ok, X509_STORE_CTX *e);
70static int check_issued(X509_STORE_CTX *ctx, X509 *x, X509 *issuer);
71static X509 *find_issuer(X509_STORE_CTX *ctx, STACK_OF(X509) *sk, X509 *x);
72static int check_chain_extensions(X509_STORE_CTX *ctx);
73static int check_name_constraints(X509_STORE_CTX *ctx);
74static int check_id(X509_STORE_CTX *ctx);
75static int check_trust(X509_STORE_CTX *ctx, int num_untrusted);
76static int check_revocation(X509_STORE_CTX *ctx);
77static int check_cert(X509_STORE_CTX *ctx);
78static int check_policy(X509_STORE_CTX *ctx);
79static int get_issuer_sk(X509 **issuer, X509_STORE_CTX *ctx, X509 *x);
80static int check_dane_issuer(X509_STORE_CTX *ctx, int depth);
81static int check_key_level(X509_STORE_CTX *ctx, X509 *cert);
82static int check_sig_level(X509_STORE_CTX *ctx, X509 *cert);
83static int check_curve(X509 *cert);
84
85static int get_crl_score(X509_STORE_CTX *ctx, X509 **pissuer,
86 unsigned int *preasons, X509_CRL *crl, X509 *x);
87static int get_crl_delta(X509_STORE_CTX *ctx,
88 X509_CRL **pcrl, X509_CRL **pdcrl, X509 *x);
89static void get_delta_sk(X509_STORE_CTX *ctx, X509_CRL **dcrl,
90 int *pcrl_score, X509_CRL *base,
91 STACK_OF(X509_CRL) *crls);
92static void crl_akid_check(X509_STORE_CTX *ctx, X509_CRL *crl, X509 **pissuer,
93 int *pcrl_score);
94static int crl_crldp_check(X509 *x, X509_CRL *crl, int crl_score,
95 unsigned int *preasons);
96static int check_crl_path(X509_STORE_CTX *ctx, X509 *x);
97static int check_crl_chain(X509_STORE_CTX *ctx,
98 STACK_OF(X509) *cert_path,
99 STACK_OF(X509) *crl_path);
100
101static int internal_verify(X509_STORE_CTX *ctx);
102
103static int null_callback(int ok, X509_STORE_CTX *e)
104{
105 return ok;
106}
107
108/*
109 * Return 1 if given cert is considered self-signed, 0 if not or on error.
110 * This does not verify self-signedness but relies on x509v3_cache_extensions()
111 * matching issuer and subject names (i.e., the cert being self-issued) and any
112 * present authority key identifier matching the subject key identifier, etc.
113 */
114static int cert_self_signed(X509 *x)
115{
116 if (X509_check_purpose(x, -1, 0) != 1)
117 return 0;
118 if (x->ex_flags & EXFLAG_SS)
119 return 1;
120 else
121 return 0;
122}
123
124/* Given a certificate try and find an exact match in the store */
125
126static X509 *lookup_cert_match(X509_STORE_CTX *ctx, X509 *x)
127{
128 STACK_OF(X509) *certs;
129 X509 *xtmp = NULL;
130 int i;
131 /* Lookup all certs with matching subject name */
132 certs = ctx->lookup_certs(ctx, X509_get_subject_name(x));
133 if (certs == NULL)
134 return NULL;
135 /* Look for exact match */
136 for (i = 0; i < sk_X509_num(certs); i++) {
137 xtmp = sk_X509_value(certs, i);
138 if (!X509_cmp(xtmp, x))
139 break;
140 xtmp = NULL;
141 }
142 if (xtmp != NULL && !X509_up_ref(xtmp))
143 xtmp = NULL;
144 sk_X509_pop_free(certs, X509_free);
145 return xtmp;
146}
147
148/*-
149 * Inform the verify callback of an error.
150 * If B<x> is not NULL it is the error cert, otherwise use the chain cert at
151 * B<depth>.
152 * If B<err> is not X509_V_OK, that's the error value, otherwise leave
153 * unchanged (presumably set by the caller).
154 *
155 * Returns 0 to abort verification with an error, non-zero to continue.
156 */
157static int verify_cb_cert(X509_STORE_CTX *ctx, X509 *x, int depth, int err)
158{
159 ctx->error_depth = depth;
160 ctx->current_cert = (x != NULL) ? x : sk_X509_value(ctx->chain, depth);
161 if (err != X509_V_OK)
162 ctx->error = err;
163 return ctx->verify_cb(0, ctx);
164}
165
166/*-
167 * Inform the verify callback of an error, CRL-specific variant. Here, the
168 * error depth and certificate are already set, we just specify the error
169 * number.
170 *
171 * Returns 0 to abort verification with an error, non-zero to continue.
172 */
173static int verify_cb_crl(X509_STORE_CTX *ctx, int err)
174{
175 ctx->error = err;
176 return ctx->verify_cb(0, ctx);
177}
178
179static int check_auth_level(X509_STORE_CTX *ctx)
180{
181 int i;
182 int num = sk_X509_num(ctx->chain);
183
184 if (ctx->param->auth_level <= 0)
185 return 1;
186
187 for (i = 0; i < num; ++i) {
188 X509 *cert = sk_X509_value(ctx->chain, i);
189
190 /*
191 * We've already checked the security of the leaf key, so here we only
192 * check the security of issuer keys.
193 */
194 if (i > 0 && !check_key_level(ctx, cert) &&
195 verify_cb_cert(ctx, cert, i, X509_V_ERR_CA_KEY_TOO_SMALL) == 0)
196 return 0;
197 /*
198 * We also check the signature algorithm security of all certificates
199 * except those of the trust anchor at index num-1.
200 */
201 if (i < num - 1 && !check_sig_level(ctx, cert) &&
202 verify_cb_cert(ctx, cert, i, X509_V_ERR_CA_MD_TOO_WEAK) == 0)
203 return 0;
204 }
205 return 1;
206}
207
208static int verify_chain(X509_STORE_CTX *ctx)
209{
210 int err;
211 int ok;
212
213 /*
214 * Before either returning with an error, or continuing with CRL checks,
215 * instantiate chain public key parameters.
216 */
217 if ((ok = build_chain(ctx)) == 0 ||
218 (ok = check_chain_extensions(ctx)) == 0 ||
219 (ok = check_auth_level(ctx)) == 0 ||
220 (ok = check_id(ctx)) == 0 || 1)
221 X509_get_pubkey_parameters(NULL, ctx->chain);
222 if (ok == 0 || (ok = ctx->check_revocation(ctx)) == 0)
223 return ok;
224
225 err = X509_chain_check_suiteb(&ctx->error_depth, NULL, ctx->chain,
226 ctx->param->flags);
227 if (err != X509_V_OK) {
228 if ((ok = verify_cb_cert(ctx, NULL, ctx->error_depth, err)) == 0)
229 return ok;
230 }
231
232 /* Verify chain signatures and expiration times */
233 ok = (ctx->verify != NULL) ? ctx->verify(ctx) : internal_verify(ctx);
234 if (!ok)
235 return ok;
236
237 if ((ok = check_name_constraints(ctx)) == 0)
238 return ok;
239
240#ifndef OPENSSL_NO_RFC3779
241 /* RFC 3779 path validation, now that CRL check has been done */
242 if ((ok = X509v3_asid_validate_path(ctx)) == 0)
243 return ok;
244 if ((ok = X509v3_addr_validate_path(ctx)) == 0)
245 return ok;
246#endif
247
248 /* If we get this far evaluate policies */
249 if (ctx->param->flags & X509_V_FLAG_POLICY_CHECK)
250 ok = ctx->check_policy(ctx);
251 return ok;
252}
253
254int X509_verify_cert(X509_STORE_CTX *ctx)
255{
256 SSL_DANE *dane = ctx->dane;
257 int ret;
258
259 if (ctx->cert == NULL) {
260 X509err(X509_F_X509_VERIFY_CERT, X509_R_NO_CERT_SET_FOR_US_TO_VERIFY);
261 ctx->error = X509_V_ERR_INVALID_CALL;
262 return -1;
263 }
264
265 if (ctx->chain != NULL) {
266 /*
267 * This X509_STORE_CTX has already been used to verify a cert. We
268 * cannot do another one.
269 */
270 X509err(X509_F_X509_VERIFY_CERT, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
271 ctx->error = X509_V_ERR_INVALID_CALL;
272 return -1;
273 }
274
275 if (!X509_up_ref(ctx->cert)) {
276 X509err(X509_F_X509_VERIFY_CERT, ERR_R_INTERNAL_ERROR);
277 ctx->error = X509_V_ERR_UNSPECIFIED;
278 return -1;
279 }
280
281 /*
282 * first we make sure the chain we are going to build is present and that
283 * the first entry is in place
284 */
285 if ((ctx->chain = sk_X509_new_null()) == NULL
286 || !sk_X509_push(ctx->chain, ctx->cert)) {
287 X509_free(ctx->cert);
288 X509err(X509_F_X509_VERIFY_CERT, ERR_R_MALLOC_FAILURE);
289 ctx->error = X509_V_ERR_OUT_OF_MEM;
290 return -1;
291 }
292
293 ctx->num_untrusted = 1;
294
295 /* If the peer's public key is too weak, we can stop early. */
296 if (!check_key_level(ctx, ctx->cert) &&
297 !verify_cb_cert(ctx, ctx->cert, 0, X509_V_ERR_EE_KEY_TOO_SMALL))
298 return 0;
299
300 if (DANETLS_ENABLED(dane))
301 ret = dane_verify(ctx);
302 else
303 ret = verify_chain(ctx);
304
305 /*
306 * Safety-net. If we are returning an error, we must also set ctx->error,
307 * so that the chain is not considered verified should the error be ignored
308 * (e.g. TLS with SSL_VERIFY_NONE).
309 */
310 if (ret <= 0 && ctx->error == X509_V_OK)
311 ctx->error = X509_V_ERR_UNSPECIFIED;
312 return ret;
313}
314
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 a non-expired issuer cert (if any) of given cert x.
327 * The issuer must not be the same as x and must not yet be in ctx->chain, where the
328 * exceptional case x is self-issued and ctx->chain has just one element is allowed.
329 */
330static X509 *find_issuer(X509_STORE_CTX *ctx, STACK_OF(X509) *sk, X509 *x)
331{
332 int i;
333 X509 *issuer, *rv = NULL;
334
335 for (i = 0; i < sk_X509_num(sk); i++) {
336 issuer = sk_X509_value(sk, i);
337 /*
338 * Below check 'issuer != x' is an optimization and safety precaution:
339 * Candidate issuer cert cannot be the same as the subject cert 'x'.
340 */
341 if (issuer != x && ctx->check_issued(ctx, x, issuer)
342 && (((x->ex_flags & EXFLAG_SI) != 0 && sk_X509_num(ctx->chain) == 1)
343 || !sk_X509_contains(ctx->chain, issuer))) {
344 rv = issuer;
345 if (x509_check_cert_time(ctx, rv, -1))
346 break;
347 }
348 }
349 return rv;
350}
351
352/* Check that the given certificate 'x' is issued by the certificate 'issuer' */
353static int check_issued(X509_STORE_CTX *ctx, X509 *x, X509 *issuer)
354{
355 return x509_likely_issued(issuer, x) == X509_V_OK;
356}
357
358/* Alternative lookup method: look from a STACK stored in other_ctx */
359static int get_issuer_sk(X509 **issuer, X509_STORE_CTX *ctx, X509 *x)
360{
361 *issuer = find_issuer(ctx, ctx->other_ctx, x);
362
363 if (*issuer == NULL || !X509_up_ref(*issuer))
364 goto err;
365
366 return 1;
367
368 err:
369 *issuer = NULL;
370 return 0;
371}
372
373static STACK_OF(X509) *lookup_certs_sk(X509_STORE_CTX *ctx, X509_NAME *nm)
374{
375 STACK_OF(X509) *sk = NULL;
376 X509 *x;
377 int i;
378
379 for (i = 0; i < sk_X509_num(ctx->other_ctx); i++) {
380 x = sk_X509_value(ctx->other_ctx, i);
381 if (X509_NAME_cmp(nm, X509_get_subject_name(x)) == 0) {
382 if (!X509_up_ref(x)) {
383 sk_X509_pop_free(sk, X509_free);
384 X509err(X509_F_LOOKUP_CERTS_SK, ERR_R_INTERNAL_ERROR);
385 ctx->error = X509_V_ERR_UNSPECIFIED;
386 return NULL;
387 }
388 if (sk == NULL)
389 sk = sk_X509_new_null();
390 if (sk == NULL || !sk_X509_push(sk, x)) {
391 X509_free(x);
392 sk_X509_pop_free(sk, X509_free);
393 X509err(X509_F_LOOKUP_CERTS_SK, ERR_R_MALLOC_FAILURE);
394 ctx->error = X509_V_ERR_OUT_OF_MEM;
395 return NULL;
396 }
397 }
398 }
399 return sk;
400}
401
402/*
403 * Check EE or CA certificate purpose. For trusted certificates explicit local
404 * auxiliary trust can be used to override EKU-restrictions.
405 */
406static int check_purpose(X509_STORE_CTX *ctx, X509 *x, int purpose, int depth,
407 int must_be_ca)
408{
409 int tr_ok = X509_TRUST_UNTRUSTED;
410
411 /*
412 * For trusted certificates we want to see whether any auxiliary trust
413 * settings trump the purpose constraints.
414 *
415 * This is complicated by the fact that the trust ordinals in
416 * ctx->param->trust are entirely independent of the purpose ordinals in
417 * ctx->param->purpose!
418 *
419 * What connects them is their mutual initialization via calls from
420 * X509_STORE_CTX_set_default() into X509_VERIFY_PARAM_lookup() which sets
421 * related values of both param->trust and param->purpose. It is however
422 * typically possible to infer associated trust values from a purpose value
423 * via the X509_PURPOSE API.
424 *
425 * Therefore, we can only check for trust overrides when the purpose we're
426 * checking is the same as ctx->param->purpose and ctx->param->trust is
427 * also set.
428 */
429 if (depth >= ctx->num_untrusted && purpose == ctx->param->purpose)
430 tr_ok = X509_check_trust(x, ctx->param->trust, X509_TRUST_NO_SS_COMPAT);
431
432 switch (tr_ok) {
433 case X509_TRUST_TRUSTED:
434 return 1;
435 case X509_TRUST_REJECTED:
436 break;
437 default:
438 switch (X509_check_purpose(x, purpose, must_be_ca > 0)) {
439 case 1:
440 return 1;
441 case 0:
442 break;
443 default:
444 if ((ctx->param->flags & X509_V_FLAG_X509_STRICT) == 0)
445 return 1;
446 }
447 break;
448 }
449
450 return verify_cb_cert(ctx, x, depth, X509_V_ERR_INVALID_PURPOSE);
451}
452
453/*
454 * Check a certificate chains extensions for consistency with the supplied
455 * purpose
456 */
457
458static int check_chain_extensions(X509_STORE_CTX *ctx)
459{
460 int i, must_be_ca, plen = 0;
461 X509 *x;
462 int proxy_path_length = 0;
463 int purpose;
464 int allow_proxy_certs;
465 int num = sk_X509_num(ctx->chain);
466
467 /*-
468 * must_be_ca can have 1 of 3 values:
469 * -1: we accept both CA and non-CA certificates, to allow direct
470 * use of self-signed certificates (which are marked as CA).
471 * 0: we only accept non-CA certificates. This is currently not
472 * used, but the possibility is present for future extensions.
473 * 1: we only accept CA certificates. This is currently used for
474 * all certificates in the chain except the leaf certificate.
475 */
476 must_be_ca = -1;
477
478 /* CRL path validation */
479 if (ctx->parent) {
480 allow_proxy_certs = 0;
481 purpose = X509_PURPOSE_CRL_SIGN;
482 } else {
483 allow_proxy_certs =
484 ! !(ctx->param->flags & X509_V_FLAG_ALLOW_PROXY_CERTS);
485 purpose = ctx->param->purpose;
486 }
487
488 for (i = 0; i < num; i++) {
489 int ret;
490 x = sk_X509_value(ctx->chain, i);
491 if (!(ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL)
492 && (x->ex_flags & EXFLAG_CRITICAL)) {
493 if (!verify_cb_cert(ctx, x, i,
494 X509_V_ERR_UNHANDLED_CRITICAL_EXTENSION))
495 return 0;
496 }
497 if (!allow_proxy_certs && (x->ex_flags & EXFLAG_PROXY)) {
498 if (!verify_cb_cert(ctx, x, i,
499 X509_V_ERR_PROXY_CERTIFICATES_NOT_ALLOWED))
500 return 0;
501 }
502 ret = X509_check_ca(x);
503 switch (must_be_ca) {
504 case -1:
505 if ((ctx->param->flags & X509_V_FLAG_X509_STRICT)
506 && (ret != 1) && (ret != 0)) {
507 ret = 0;
508 ctx->error = X509_V_ERR_INVALID_CA;
509 } else
510 ret = 1;
511 break;
512 case 0:
513 if (ret != 0) {
514 ret = 0;
515 ctx->error = X509_V_ERR_INVALID_NON_CA;
516 } else
517 ret = 1;
518 break;
519 default:
520 /* X509_V_FLAG_X509_STRICT is implicit for intermediate CAs */
521 if ((ret == 0)
522 || ((i + 1 < num || ctx->param->flags & X509_V_FLAG_X509_STRICT)
523 && (ret != 1))) {
524 ret = 0;
525 ctx->error = X509_V_ERR_INVALID_CA;
526 } else
527 ret = 1;
528 break;
529 }
530 if ((ctx->param->flags & X509_V_FLAG_X509_STRICT) && num > 1) {
531 /* Check for presence of explicit elliptic curve parameters */
532 ret = check_curve(x);
533 if (ret < 0)
534 ctx->error = X509_V_ERR_UNSPECIFIED;
535 else if (ret == 0)
536 ctx->error = X509_V_ERR_EC_KEY_EXPLICIT_PARAMS;
537 }
538 if ((x->ex_flags & EXFLAG_CA) == 0
539 && x->ex_pathlen != -1
540 && (ctx->param->flags & X509_V_FLAG_X509_STRICT)) {
541 ctx->error = X509_V_ERR_INVALID_EXTENSION;
542 ret = 0;
543 }
544 if (ret == 0 && !verify_cb_cert(ctx, x, i, X509_V_OK))
545 return 0;
546 /* check_purpose() makes the callback as needed */
547 if (purpose > 0 && !check_purpose(ctx, x, purpose, i, must_be_ca))
548 return 0;
549 /* Check pathlen */
550 if ((i > 1) && (x->ex_pathlen != -1)
551 && (plen > (x->ex_pathlen + proxy_path_length))) {
552 if (!verify_cb_cert(ctx, x, i, X509_V_ERR_PATH_LENGTH_EXCEEDED))
553 return 0;
554 }
555 /* Increment path length if not a self issued intermediate CA */
556 if (i > 0 && (x->ex_flags & EXFLAG_SI) == 0)
557 plen++;
558 /*
559 * If this certificate is a proxy certificate, the next certificate
560 * must be another proxy certificate or a EE certificate. If not,
561 * the next certificate must be a CA certificate.
562 */
563 if (x->ex_flags & EXFLAG_PROXY) {
564 /*
565 * RFC3820, 4.1.3 (b)(1) stipulates that if pCPathLengthConstraint
566 * is less than max_path_length, the former should be copied to
567 * the latter, and 4.1.4 (a) stipulates that max_path_length
568 * should be verified to be larger than zero and decrement it.
569 *
570 * Because we're checking the certs in the reverse order, we start
571 * with verifying that proxy_path_length isn't larger than pcPLC,
572 * and copy the latter to the former if it is, and finally,
573 * increment proxy_path_length.
574 */
575 if (x->ex_pcpathlen != -1) {
576 if (proxy_path_length > x->ex_pcpathlen) {
577 if (!verify_cb_cert(ctx, x, i,
578 X509_V_ERR_PROXY_PATH_LENGTH_EXCEEDED))
579 return 0;
580 }
581 proxy_path_length = x->ex_pcpathlen;
582 }
583 proxy_path_length++;
584 must_be_ca = 0;
585 } else
586 must_be_ca = 1;
587 }
588 return 1;
589}
590
591static int has_san_id(X509 *x, int gtype)
592{
593 int i;
594 int ret = 0;
595 GENERAL_NAMES *gs = X509_get_ext_d2i(x, NID_subject_alt_name, NULL, NULL);
596
597 if (gs == NULL)
598 return 0;
599
600 for (i = 0; i < sk_GENERAL_NAME_num(gs); i++) {
601 GENERAL_NAME *g = sk_GENERAL_NAME_value(gs, i);
602
603 if (g->type == gtype) {
604 ret = 1;
605 break;
606 }
607 }
608 GENERAL_NAMES_free(gs);
609 return ret;
610}
611
612static int check_name_constraints(X509_STORE_CTX *ctx)
613{
614 int i;
615
616 /* Check name constraints for all certificates */
617 for (i = sk_X509_num(ctx->chain) - 1; i >= 0; i--) {
618 X509 *x = sk_X509_value(ctx->chain, i);
619 int j;
620
621 /* Ignore self issued certs unless last in chain */
622 if (i && (x->ex_flags & EXFLAG_SI))
623 continue;
624
625 /*
626 * Proxy certificates policy has an extra constraint, where the
627 * certificate subject MUST be the issuer with a single CN entry
628 * added.
629 * (RFC 3820: 3.4, 4.1.3 (a)(4))
630 */
631 if (x->ex_flags & EXFLAG_PROXY) {
632 X509_NAME *tmpsubject = X509_get_subject_name(x);
633 X509_NAME *tmpissuer = X509_get_issuer_name(x);
634 X509_NAME_ENTRY *tmpentry = NULL;
635 int last_object_nid = 0;
636 int err = X509_V_OK;
637 int last_object_loc = X509_NAME_entry_count(tmpsubject) - 1;
638
639 /* Check that there are at least two RDNs */
640 if (last_object_loc < 1) {
641 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
642 goto proxy_name_done;
643 }
644
645 /*
646 * Check that there is exactly one more RDN in subject as
647 * there is in issuer.
648 */
649 if (X509_NAME_entry_count(tmpsubject)
650 != X509_NAME_entry_count(tmpissuer) + 1) {
651 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
652 goto proxy_name_done;
653 }
654
655 /*
656 * Check that the last subject component isn't part of a
657 * multivalued RDN
658 */
659 if (X509_NAME_ENTRY_set(X509_NAME_get_entry(tmpsubject,
660 last_object_loc))
661 == X509_NAME_ENTRY_set(X509_NAME_get_entry(tmpsubject,
662 last_object_loc - 1))) {
663 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
664 goto proxy_name_done;
665 }
666
667 /*
668 * Check that the last subject RDN is a commonName, and that
669 * all the previous RDNs match the issuer exactly
670 */
671 tmpsubject = X509_NAME_dup(tmpsubject);
672 if (tmpsubject == NULL) {
673 X509err(X509_F_CHECK_NAME_CONSTRAINTS, ERR_R_MALLOC_FAILURE);
674 ctx->error = X509_V_ERR_OUT_OF_MEM;
675 return 0;
676 }
677
678 tmpentry =
679 X509_NAME_delete_entry(tmpsubject, last_object_loc);
680 last_object_nid =
681 OBJ_obj2nid(X509_NAME_ENTRY_get_object(tmpentry));
682
683 if (last_object_nid != NID_commonName
684 || X509_NAME_cmp(tmpsubject, tmpissuer) != 0) {
685 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
686 }
687
688 X509_NAME_ENTRY_free(tmpentry);
689 X509_NAME_free(tmpsubject);
690
691 proxy_name_done:
692 if (err != X509_V_OK
693 && !verify_cb_cert(ctx, x, i, err))
694 return 0;
695 }
696
697 /*
698 * Check against constraints for all certificates higher in chain
699 * including trust anchor. Trust anchor not strictly speaking needed
700 * but if it includes constraints it is to be assumed it expects them
701 * to be obeyed.
702 */
703 for (j = sk_X509_num(ctx->chain) - 1; j > i; j--) {
704 NAME_CONSTRAINTS *nc = sk_X509_value(ctx->chain, j)->nc;
705
706 if (nc) {
707 int rv = NAME_CONSTRAINTS_check(x, nc);
708
709 /* If EE certificate check commonName too */
710 if (rv == X509_V_OK && i == 0
711 && (ctx->param->hostflags
712 & X509_CHECK_FLAG_NEVER_CHECK_SUBJECT) == 0
713 && ((ctx->param->hostflags
714 & X509_CHECK_FLAG_ALWAYS_CHECK_SUBJECT) != 0
715 || !has_san_id(x, GEN_DNS)))
716 rv = NAME_CONSTRAINTS_check_CN(x, nc);
717
718 switch (rv) {
719 case X509_V_OK:
720 break;
721 case X509_V_ERR_OUT_OF_MEM:
722 return 0;
723 default:
724 if (!verify_cb_cert(ctx, x, i, rv))
725 return 0;
726 break;
727 }
728 }
729 }
730 }
731 return 1;
732}
733
734static int check_id_error(X509_STORE_CTX *ctx, int errcode)
735{
736 return verify_cb_cert(ctx, ctx->cert, 0, errcode);
737}
738
739static int check_hosts(X509 *x, X509_VERIFY_PARAM *vpm)
740{
741 int i;
742 int n = sk_OPENSSL_STRING_num(vpm->hosts);
743 char *name;
744
745 if (vpm->peername != NULL) {
746 OPENSSL_free(vpm->peername);
747 vpm->peername = NULL;
748 }
749 for (i = 0; i < n; ++i) {
750 name = sk_OPENSSL_STRING_value(vpm->hosts, i);
751 if (X509_check_host(x, name, 0, vpm->hostflags, &vpm->peername) > 0)
752 return 1;
753 }
754 return n == 0;
755}
756
757static int check_id(X509_STORE_CTX *ctx)
758{
759 X509_VERIFY_PARAM *vpm = ctx->param;
760 X509 *x = ctx->cert;
761 if (vpm->hosts && check_hosts(x, vpm) <= 0) {
762 if (!check_id_error(ctx, X509_V_ERR_HOSTNAME_MISMATCH))
763 return 0;
764 }
765 if (vpm->email && X509_check_email(x, vpm->email, vpm->emaillen, 0) <= 0) {
766 if (!check_id_error(ctx, X509_V_ERR_EMAIL_MISMATCH))
767 return 0;
768 }
769 if (vpm->ip && X509_check_ip(x, vpm->ip, vpm->iplen, 0) <= 0) {
770 if (!check_id_error(ctx, X509_V_ERR_IP_ADDRESS_MISMATCH))
771 return 0;
772 }
773 return 1;
774}
775
776static int check_trust(X509_STORE_CTX *ctx, int num_untrusted)
777{
778 int i;
779 X509 *x = NULL;
780 X509 *mx;
781 SSL_DANE *dane = ctx->dane;
782 int num = sk_X509_num(ctx->chain);
783 int trust;
784
785 /*
786 * Check for a DANE issuer at depth 1 or greater, if it is a DANE-TA(2)
787 * match, we're done, otherwise we'll merely record the match depth.
788 */
789 if (DANETLS_HAS_TA(dane) && num_untrusted > 0 && num_untrusted < num) {
790 switch (trust = check_dane_issuer(ctx, num_untrusted)) {
791 case X509_TRUST_TRUSTED:
792 case X509_TRUST_REJECTED:
793 return trust;
794 }
795 }
796
797 /*
798 * Check trusted certificates in chain at depth num_untrusted and up.
799 * Note, that depths 0..num_untrusted-1 may also contain trusted
800 * certificates, but the caller is expected to have already checked those,
801 * and wants to incrementally check just any added since.
802 */
803 for (i = num_untrusted; i < num; i++) {
804 x = sk_X509_value(ctx->chain, i);
805 trust = X509_check_trust(x, ctx->param->trust, 0);
806 /* If explicitly trusted return trusted */
807 if (trust == X509_TRUST_TRUSTED)
808 goto trusted;
809 if (trust == X509_TRUST_REJECTED)
810 goto rejected;
811 }
812
813 /*
814 * If we are looking at a trusted certificate, and accept partial chains,
815 * the chain is PKIX trusted.
816 */
817 if (num_untrusted < num) {
818 if (ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN)
819 goto trusted;
820 return X509_TRUST_UNTRUSTED;
821 }
822
823 if (num_untrusted == num && ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) {
824 /*
825 * Last-resort call with no new trusted certificates, check the leaf
826 * for a direct trust store match.
827 */
828 i = 0;
829 x = sk_X509_value(ctx->chain, i);
830 mx = lookup_cert_match(ctx, x);
831 if (!mx)
832 return X509_TRUST_UNTRUSTED;
833
834 /*
835 * Check explicit auxiliary trust/reject settings. If none are set,
836 * we'll accept X509_TRUST_UNTRUSTED when not self-signed.
837 */
838 trust = X509_check_trust(mx, ctx->param->trust, 0);
839 if (trust == X509_TRUST_REJECTED) {
840 X509_free(mx);
841 goto rejected;
842 }
843
844 /* Replace leaf with trusted match */
845 (void) sk_X509_set(ctx->chain, 0, mx);
846 X509_free(x);
847 ctx->num_untrusted = 0;
848 goto trusted;
849 }
850
851 /*
852 * If no trusted certs in chain at all return untrusted and allow
853 * standard (no issuer cert) etc errors to be indicated.
854 */
855 return X509_TRUST_UNTRUSTED;
856
857 rejected:
858 if (!verify_cb_cert(ctx, x, i, X509_V_ERR_CERT_REJECTED))
859 return X509_TRUST_REJECTED;
860 return X509_TRUST_UNTRUSTED;
861
862 trusted:
863 if (!DANETLS_ENABLED(dane))
864 return X509_TRUST_TRUSTED;
865 if (dane->pdpth < 0)
866 dane->pdpth = num_untrusted;
867 /* With DANE, PKIX alone is not trusted until we have both */
868 if (dane->mdpth >= 0)
869 return X509_TRUST_TRUSTED;
870 return X509_TRUST_UNTRUSTED;
871}
872
873static int check_revocation(X509_STORE_CTX *ctx)
874{
875 int i = 0, last = 0, ok = 0;
876 if (!(ctx->param->flags & X509_V_FLAG_CRL_CHECK))
877 return 1;
878 if (ctx->param->flags & X509_V_FLAG_CRL_CHECK_ALL)
879 last = sk_X509_num(ctx->chain) - 1;
880 else {
881 /* If checking CRL paths this isn't the EE certificate */
882 if (ctx->parent)
883 return 1;
884 last = 0;
885 }
886 for (i = 0; i <= last; i++) {
887 ctx->error_depth = i;
888 ok = check_cert(ctx);
889 if (!ok)
890 return ok;
891 }
892 return 1;
893}
894
895static int check_cert(X509_STORE_CTX *ctx)
896{
897 X509_CRL *crl = NULL, *dcrl = NULL;
898 int ok = 0;
899 int cnum = ctx->error_depth;
900 X509 *x = sk_X509_value(ctx->chain, cnum);
901
902 ctx->current_cert = x;
903 ctx->current_issuer = NULL;
904 ctx->current_crl_score = 0;
905 ctx->current_reasons = 0;
906
907 if (x->ex_flags & EXFLAG_PROXY)
908 return 1;
909
910 while (ctx->current_reasons != CRLDP_ALL_REASONS) {
911 unsigned int last_reasons = ctx->current_reasons;
912
913 /* Try to retrieve relevant CRL */
914 if (ctx->get_crl)
915 ok = ctx->get_crl(ctx, &crl, x);
916 else
917 ok = get_crl_delta(ctx, &crl, &dcrl, x);
918 /*
919 * If error looking up CRL, nothing we can do except notify callback
920 */
921 if (!ok) {
922 ok = verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL);
923 goto done;
924 }
925 ctx->current_crl = crl;
926 ok = ctx->check_crl(ctx, crl);
927 if (!ok)
928 goto done;
929
930 if (dcrl) {
931 ok = ctx->check_crl(ctx, dcrl);
932 if (!ok)
933 goto done;
934 ok = ctx->cert_crl(ctx, dcrl, x);
935 if (!ok)
936 goto done;
937 } else
938 ok = 1;
939
940 /* Don't look in full CRL if delta reason is removefromCRL */
941 if (ok != 2) {
942 ok = ctx->cert_crl(ctx, crl, x);
943 if (!ok)
944 goto done;
945 }
946
947 X509_CRL_free(crl);
948 X509_CRL_free(dcrl);
949 crl = NULL;
950 dcrl = NULL;
951 /*
952 * If reasons not updated we won't get anywhere by another iteration,
953 * so exit loop.
954 */
955 if (last_reasons == ctx->current_reasons) {
956 ok = verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL);
957 goto done;
958 }
959 }
960 done:
961 X509_CRL_free(crl);
962 X509_CRL_free(dcrl);
963
964 ctx->current_crl = NULL;
965 return ok;
966}
967
968/* Check CRL times against values in X509_STORE_CTX */
969
970static int check_crl_time(X509_STORE_CTX *ctx, X509_CRL *crl, int notify)
971{
972 time_t *ptime;
973 int i;
974
975 if (notify)
976 ctx->current_crl = crl;
977 if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME)
978 ptime = &ctx->param->check_time;
979 else if (ctx->param->flags & X509_V_FLAG_NO_CHECK_TIME)
980 return 1;
981 else
982 ptime = NULL;
983
984 i = X509_cmp_time(X509_CRL_get0_lastUpdate(crl), ptime);
985 if (i == 0) {
986 if (!notify)
987 return 0;
988 if (!verify_cb_crl(ctx, X509_V_ERR_ERROR_IN_CRL_LAST_UPDATE_FIELD))
989 return 0;
990 }
991
992 if (i > 0) {
993 if (!notify)
994 return 0;
995 if (!verify_cb_crl(ctx, X509_V_ERR_CRL_NOT_YET_VALID))
996 return 0;
997 }
998
999 if (X509_CRL_get0_nextUpdate(crl)) {
1000 i = X509_cmp_time(X509_CRL_get0_nextUpdate(crl), ptime);
1001
1002 if (i == 0) {
1003 if (!notify)
1004 return 0;
1005 if (!verify_cb_crl(ctx, X509_V_ERR_ERROR_IN_CRL_NEXT_UPDATE_FIELD))
1006 return 0;
1007 }
1008 /* Ignore expiry of base CRL is delta is valid */
1009 if ((i < 0) && !(ctx->current_crl_score & CRL_SCORE_TIME_DELTA)) {
1010 if (!notify)
1011 return 0;
1012 if (!verify_cb_crl(ctx, X509_V_ERR_CRL_HAS_EXPIRED))
1013 return 0;
1014 }
1015 }
1016
1017 if (notify)
1018 ctx->current_crl = NULL;
1019
1020 return 1;
1021}
1022
1023static int get_crl_sk(X509_STORE_CTX *ctx, X509_CRL **pcrl, X509_CRL **pdcrl,
1024 X509 **pissuer, int *pscore, unsigned int *preasons,
1025 STACK_OF(X509_CRL) *crls)
1026{
1027 int i, crl_score, best_score = *pscore;
1028 unsigned int reasons, best_reasons = 0;
1029 X509 *x = ctx->current_cert;
1030 X509_CRL *crl, *best_crl = NULL;
1031 X509 *crl_issuer = NULL, *best_crl_issuer = NULL;
1032
1033 for (i = 0; i < sk_X509_CRL_num(crls); i++) {
1034 crl = sk_X509_CRL_value(crls, i);
1035 reasons = *preasons;
1036 crl_score = get_crl_score(ctx, &crl_issuer, &reasons, crl, x);
1037 if (crl_score < best_score || crl_score == 0)
1038 continue;
1039 /* If current CRL is equivalent use it if it is newer */
1040 if (crl_score == best_score && best_crl != NULL) {
1041 int day, sec;
1042 if (ASN1_TIME_diff(&day, &sec, X509_CRL_get0_lastUpdate(best_crl),
1043 X509_CRL_get0_lastUpdate(crl)) == 0)
1044 continue;
1045 /*
1046 * ASN1_TIME_diff never returns inconsistent signs for |day|
1047 * and |sec|.
1048 */
1049 if (day <= 0 && sec <= 0)
1050 continue;
1051 }
1052 best_crl = crl;
1053 best_crl_issuer = crl_issuer;
1054 best_score = crl_score;
1055 best_reasons = reasons;
1056 }
1057
1058 if (best_crl) {
1059 X509_CRL_free(*pcrl);
1060 *pcrl = best_crl;
1061 *pissuer = best_crl_issuer;
1062 *pscore = best_score;
1063 *preasons = best_reasons;
1064 X509_CRL_up_ref(best_crl);
1065 X509_CRL_free(*pdcrl);
1066 *pdcrl = NULL;
1067 get_delta_sk(ctx, pdcrl, pscore, best_crl, crls);
1068 }
1069
1070 if (best_score >= CRL_SCORE_VALID)
1071 return 1;
1072
1073 return 0;
1074}
1075
1076/*
1077 * Compare two CRL extensions for delta checking purposes. They should be
1078 * both present or both absent. If both present all fields must be identical.
1079 */
1080
1081static int crl_extension_match(X509_CRL *a, X509_CRL *b, int nid)
1082{
1083 ASN1_OCTET_STRING *exta, *extb;
1084 int i;
1085 i = X509_CRL_get_ext_by_NID(a, nid, -1);
1086 if (i >= 0) {
1087 /* Can't have multiple occurrences */
1088 if (X509_CRL_get_ext_by_NID(a, nid, i) != -1)
1089 return 0;
1090 exta = X509_EXTENSION_get_data(X509_CRL_get_ext(a, i));
1091 } else
1092 exta = NULL;
1093
1094 i = X509_CRL_get_ext_by_NID(b, nid, -1);
1095
1096 if (i >= 0) {
1097
1098 if (X509_CRL_get_ext_by_NID(b, nid, i) != -1)
1099 return 0;
1100 extb = X509_EXTENSION_get_data(X509_CRL_get_ext(b, i));
1101 } else
1102 extb = NULL;
1103
1104 if (!exta && !extb)
1105 return 1;
1106
1107 if (!exta || !extb)
1108 return 0;
1109
1110 if (ASN1_OCTET_STRING_cmp(exta, extb))
1111 return 0;
1112
1113 return 1;
1114}
1115
1116/* See if a base and delta are compatible */
1117
1118static int check_delta_base(X509_CRL *delta, X509_CRL *base)
1119{
1120 /* Delta CRL must be a delta */
1121 if (!delta->base_crl_number)
1122 return 0;
1123 /* Base must have a CRL number */
1124 if (!base->crl_number)
1125 return 0;
1126 /* Issuer names must match */
1127 if (X509_NAME_cmp(X509_CRL_get_issuer(base), X509_CRL_get_issuer(delta)))
1128 return 0;
1129 /* AKID and IDP must match */
1130 if (!crl_extension_match(delta, base, NID_authority_key_identifier))
1131 return 0;
1132 if (!crl_extension_match(delta, base, NID_issuing_distribution_point))
1133 return 0;
1134 /* Delta CRL base number must not exceed Full CRL number. */
1135 if (ASN1_INTEGER_cmp(delta->base_crl_number, base->crl_number) > 0)
1136 return 0;
1137 /* Delta CRL number must exceed full CRL number */
1138 if (ASN1_INTEGER_cmp(delta->crl_number, base->crl_number) > 0)
1139 return 1;
1140 return 0;
1141}
1142
1143/*
1144 * For a given base CRL find a delta... maybe extend to delta scoring or
1145 * retrieve a chain of deltas...
1146 */
1147
1148static void get_delta_sk(X509_STORE_CTX *ctx, X509_CRL **dcrl, int *pscore,
1149 X509_CRL *base, STACK_OF(X509_CRL) *crls)
1150{
1151 X509_CRL *delta;
1152 int i;
1153 if (!(ctx->param->flags & X509_V_FLAG_USE_DELTAS))
1154 return;
1155 if (!((ctx->current_cert->ex_flags | base->flags) & EXFLAG_FRESHEST))
1156 return;
1157 for (i = 0; i < sk_X509_CRL_num(crls); i++) {
1158 delta = sk_X509_CRL_value(crls, i);
1159 if (check_delta_base(delta, base)) {
1160 if (check_crl_time(ctx, delta, 0))
1161 *pscore |= CRL_SCORE_TIME_DELTA;
1162 X509_CRL_up_ref(delta);
1163 *dcrl = delta;
1164 return;
1165 }
1166 }
1167 *dcrl = NULL;
1168}
1169
1170/*
1171 * For a given CRL return how suitable it is for the supplied certificate
1172 * 'x'. The return value is a mask of several criteria. If the issuer is not
1173 * the certificate issuer this is returned in *pissuer. The reasons mask is
1174 * also used to determine if the CRL is suitable: if no new reasons the CRL
1175 * is rejected, otherwise reasons is updated.
1176 */
1177
1178static int get_crl_score(X509_STORE_CTX *ctx, X509 **pissuer,
1179 unsigned int *preasons, X509_CRL *crl, X509 *x)
1180{
1181
1182 int crl_score = 0;
1183 unsigned int tmp_reasons = *preasons, crl_reasons;
1184
1185 /* First see if we can reject CRL straight away */
1186
1187 /* Invalid IDP cannot be processed */
1188 if (crl->idp_flags & IDP_INVALID)
1189 return 0;
1190 /* Reason codes or indirect CRLs need extended CRL support */
1191 if (!(ctx->param->flags & X509_V_FLAG_EXTENDED_CRL_SUPPORT)) {
1192 if (crl->idp_flags & (IDP_INDIRECT | IDP_REASONS))
1193 return 0;
1194 } else if (crl->idp_flags & IDP_REASONS) {
1195 /* If no new reasons reject */
1196 if (!(crl->idp_reasons & ~tmp_reasons))
1197 return 0;
1198 }
1199 /* Don't process deltas at this stage */
1200 else if (crl->base_crl_number)
1201 return 0;
1202 /* If issuer name doesn't match certificate need indirect CRL */
1203 if (X509_NAME_cmp(X509_get_issuer_name(x), X509_CRL_get_issuer(crl))) {
1204 if (!(crl->idp_flags & IDP_INDIRECT))
1205 return 0;
1206 } else
1207 crl_score |= CRL_SCORE_ISSUER_NAME;
1208
1209 if (!(crl->flags & EXFLAG_CRITICAL))
1210 crl_score |= CRL_SCORE_NOCRITICAL;
1211
1212 /* Check expiry */
1213 if (check_crl_time(ctx, crl, 0))
1214 crl_score |= CRL_SCORE_TIME;
1215
1216 /* Check authority key ID and locate certificate issuer */
1217 crl_akid_check(ctx, crl, pissuer, &crl_score);
1218
1219 /* If we can't locate certificate issuer at this point forget it */
1220
1221 if (!(crl_score & CRL_SCORE_AKID))
1222 return 0;
1223
1224 /* Check cert for matching CRL distribution points */
1225
1226 if (crl_crldp_check(x, crl, crl_score, &crl_reasons)) {
1227 /* If no new reasons reject */
1228 if (!(crl_reasons & ~tmp_reasons))
1229 return 0;
1230 tmp_reasons |= crl_reasons;
1231 crl_score |= CRL_SCORE_SCOPE;
1232 }
1233
1234 *preasons = tmp_reasons;
1235
1236 return crl_score;
1237
1238}
1239
1240static void crl_akid_check(X509_STORE_CTX *ctx, X509_CRL *crl,
1241 X509 **pissuer, int *pcrl_score)
1242{
1243 X509 *crl_issuer = NULL;
1244 X509_NAME *cnm = X509_CRL_get_issuer(crl);
1245 int cidx = ctx->error_depth;
1246 int i;
1247
1248 if (cidx != sk_X509_num(ctx->chain) - 1)
1249 cidx++;
1250
1251 crl_issuer = sk_X509_value(ctx->chain, cidx);
1252
1253 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1254 if (*pcrl_score & CRL_SCORE_ISSUER_NAME) {
1255 *pcrl_score |= CRL_SCORE_AKID | CRL_SCORE_ISSUER_CERT;
1256 *pissuer = crl_issuer;
1257 return;
1258 }
1259 }
1260
1261 for (cidx++; cidx < sk_X509_num(ctx->chain); cidx++) {
1262 crl_issuer = sk_X509_value(ctx->chain, cidx);
1263 if (X509_NAME_cmp(X509_get_subject_name(crl_issuer), cnm))
1264 continue;
1265 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1266 *pcrl_score |= CRL_SCORE_AKID | CRL_SCORE_SAME_PATH;
1267 *pissuer = crl_issuer;
1268 return;
1269 }
1270 }
1271
1272 /* Anything else needs extended CRL support */
1273
1274 if (!(ctx->param->flags & X509_V_FLAG_EXTENDED_CRL_SUPPORT))
1275 return;
1276
1277 /*
1278 * Otherwise the CRL issuer is not on the path. Look for it in the set of
1279 * untrusted certificates.
1280 */
1281 for (i = 0; i < sk_X509_num(ctx->untrusted); i++) {
1282 crl_issuer = sk_X509_value(ctx->untrusted, i);
1283 if (X509_NAME_cmp(X509_get_subject_name(crl_issuer), cnm))
1284 continue;
1285 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1286 *pissuer = crl_issuer;
1287 *pcrl_score |= CRL_SCORE_AKID;
1288 return;
1289 }
1290 }
1291}
1292
1293/*
1294 * Check the path of a CRL issuer certificate. This creates a new
1295 * X509_STORE_CTX and populates it with most of the parameters from the
1296 * parent. This could be optimised somewhat since a lot of path checking will
1297 * be duplicated by the parent, but this will rarely be used in practice.
1298 */
1299
1300static int check_crl_path(X509_STORE_CTX *ctx, X509 *x)
1301{
1302 X509_STORE_CTX crl_ctx;
1303 int ret;
1304
1305 /* Don't allow recursive CRL path validation */
1306 if (ctx->parent)
1307 return 0;
1308 if (!X509_STORE_CTX_init(&crl_ctx, ctx->ctx, x, ctx->untrusted))
1309 return -1;
1310
1311 crl_ctx.crls = ctx->crls;
1312 /* Copy verify params across */
1313 X509_STORE_CTX_set0_param(&crl_ctx, ctx->param);
1314
1315 crl_ctx.parent = ctx;
1316 crl_ctx.verify_cb = ctx->verify_cb;
1317
1318 /* Verify CRL issuer */
1319 ret = X509_verify_cert(&crl_ctx);
1320 if (ret <= 0)
1321 goto err;
1322
1323 /* Check chain is acceptable */
1324 ret = check_crl_chain(ctx, ctx->chain, crl_ctx.chain);
1325 err:
1326 X509_STORE_CTX_cleanup(&crl_ctx);
1327 return ret;
1328}
1329
1330/*
1331 * RFC3280 says nothing about the relationship between CRL path and
1332 * certificate path, which could lead to situations where a certificate could
1333 * be revoked or validated by a CA not authorised to do so. RFC5280 is more
1334 * strict and states that the two paths must end in the same trust anchor,
1335 * though some discussions remain... until this is resolved we use the
1336 * RFC5280 version
1337 */
1338
1339static int check_crl_chain(X509_STORE_CTX *ctx,
1340 STACK_OF(X509) *cert_path,
1341 STACK_OF(X509) *crl_path)
1342{
1343 X509 *cert_ta, *crl_ta;
1344 cert_ta = sk_X509_value(cert_path, sk_X509_num(cert_path) - 1);
1345 crl_ta = sk_X509_value(crl_path, sk_X509_num(crl_path) - 1);
1346 if (!X509_cmp(cert_ta, crl_ta))
1347 return 1;
1348 return 0;
1349}
1350
1351/*-
1352 * Check for match between two dist point names: three separate cases.
1353 * 1. Both are relative names and compare X509_NAME types.
1354 * 2. One full, one relative. Compare X509_NAME to GENERAL_NAMES.
1355 * 3. Both are full names and compare two GENERAL_NAMES.
1356 * 4. One is NULL: automatic match.
1357 */
1358
1359static int idp_check_dp(DIST_POINT_NAME *a, DIST_POINT_NAME *b)
1360{
1361 X509_NAME *nm = NULL;
1362 GENERAL_NAMES *gens = NULL;
1363 GENERAL_NAME *gena, *genb;
1364 int i, j;
1365 if (!a || !b)
1366 return 1;
1367 if (a->type == 1) {
1368 if (!a->dpname)
1369 return 0;
1370 /* Case 1: two X509_NAME */
1371 if (b->type == 1) {
1372 if (!b->dpname)
1373 return 0;
1374 if (!X509_NAME_cmp(a->dpname, b->dpname))
1375 return 1;
1376 else
1377 return 0;
1378 }
1379 /* Case 2: set name and GENERAL_NAMES appropriately */
1380 nm = a->dpname;
1381 gens = b->name.fullname;
1382 } else if (b->type == 1) {
1383 if (!b->dpname)
1384 return 0;
1385 /* Case 2: set name and GENERAL_NAMES appropriately */
1386 gens = a->name.fullname;
1387 nm = b->dpname;
1388 }
1389
1390 /* Handle case 2 with one GENERAL_NAMES and one X509_NAME */
1391 if (nm) {
1392 for (i = 0; i < sk_GENERAL_NAME_num(gens); i++) {
1393 gena = sk_GENERAL_NAME_value(gens, i);
1394 if (gena->type != GEN_DIRNAME)
1395 continue;
1396 if (!X509_NAME_cmp(nm, gena->d.directoryName))
1397 return 1;
1398 }
1399 return 0;
1400 }
1401
1402 /* Else case 3: two GENERAL_NAMES */
1403
1404 for (i = 0; i < sk_GENERAL_NAME_num(a->name.fullname); i++) {
1405 gena = sk_GENERAL_NAME_value(a->name.fullname, i);
1406 for (j = 0; j < sk_GENERAL_NAME_num(b->name.fullname); j++) {
1407 genb = sk_GENERAL_NAME_value(b->name.fullname, j);
1408 if (!GENERAL_NAME_cmp(gena, genb))
1409 return 1;
1410 }
1411 }
1412
1413 return 0;
1414
1415}
1416
1417static int crldp_check_crlissuer(DIST_POINT *dp, X509_CRL *crl, int crl_score)
1418{
1419 int i;
1420 X509_NAME *nm = X509_CRL_get_issuer(crl);
1421 /* If no CRLissuer return is successful iff don't need a match */
1422 if (!dp->CRLissuer)
1423 return ! !(crl_score & CRL_SCORE_ISSUER_NAME);
1424 for (i = 0; i < sk_GENERAL_NAME_num(dp->CRLissuer); i++) {
1425 GENERAL_NAME *gen = sk_GENERAL_NAME_value(dp->CRLissuer, i);
1426 if (gen->type != GEN_DIRNAME)
1427 continue;
1428 if (!X509_NAME_cmp(gen->d.directoryName, nm))
1429 return 1;
1430 }
1431 return 0;
1432}
1433
1434/* Check CRLDP and IDP */
1435
1436static int crl_crldp_check(X509 *x, X509_CRL *crl, int crl_score,
1437 unsigned int *preasons)
1438{
1439 int i;
1440 if (crl->idp_flags & IDP_ONLYATTR)
1441 return 0;
1442 if (x->ex_flags & EXFLAG_CA) {
1443 if (crl->idp_flags & IDP_ONLYUSER)
1444 return 0;
1445 } else {
1446 if (crl->idp_flags & IDP_ONLYCA)
1447 return 0;
1448 }
1449 *preasons = crl->idp_reasons;
1450 for (i = 0; i < sk_DIST_POINT_num(x->crldp); i++) {
1451 DIST_POINT *dp = sk_DIST_POINT_value(x->crldp, i);
1452 if (crldp_check_crlissuer(dp, crl, crl_score)) {
1453 if (!crl->idp || idp_check_dp(dp->distpoint, crl->idp->distpoint)) {
1454 *preasons &= dp->dp_reasons;
1455 return 1;
1456 }
1457 }
1458 }
1459 if ((!crl->idp || !crl->idp->distpoint)
1460 && (crl_score & CRL_SCORE_ISSUER_NAME))
1461 return 1;
1462 return 0;
1463}
1464
1465/*
1466 * Retrieve CRL corresponding to current certificate. If deltas enabled try
1467 * to find a delta CRL too
1468 */
1469
1470static int get_crl_delta(X509_STORE_CTX *ctx,
1471 X509_CRL **pcrl, X509_CRL **pdcrl, X509 *x)
1472{
1473 int ok;
1474 X509 *issuer = NULL;
1475 int crl_score = 0;
1476 unsigned int reasons;
1477 X509_CRL *crl = NULL, *dcrl = NULL;
1478 STACK_OF(X509_CRL) *skcrl;
1479 X509_NAME *nm = X509_get_issuer_name(x);
1480
1481 reasons = ctx->current_reasons;
1482 ok = get_crl_sk(ctx, &crl, &dcrl,
1483 &issuer, &crl_score, &reasons, ctx->crls);
1484 if (ok)
1485 goto done;
1486
1487 /* Lookup CRLs from store */
1488
1489 skcrl = ctx->lookup_crls(ctx, nm);
1490
1491 /* If no CRLs found and a near match from get_crl_sk use that */
1492 if (!skcrl && crl)
1493 goto done;
1494
1495 get_crl_sk(ctx, &crl, &dcrl, &issuer, &crl_score, &reasons, skcrl);
1496
1497 sk_X509_CRL_pop_free(skcrl, X509_CRL_free);
1498
1499 done:
1500 /* If we got any kind of CRL use it and return success */
1501 if (crl) {
1502 ctx->current_issuer = issuer;
1503 ctx->current_crl_score = crl_score;
1504 ctx->current_reasons = reasons;
1505 *pcrl = crl;
1506 *pdcrl = dcrl;
1507 return 1;
1508 }
1509 return 0;
1510}
1511
1512/* Check CRL validity */
1513static int check_crl(X509_STORE_CTX *ctx, X509_CRL *crl)
1514{
1515 X509 *issuer = NULL;
1516 EVP_PKEY *ikey = NULL;
1517 int cnum = ctx->error_depth;
1518 int chnum = sk_X509_num(ctx->chain) - 1;
1519
1520 /* if we have an alternative CRL issuer cert use that */
1521 if (ctx->current_issuer)
1522 issuer = ctx->current_issuer;
1523 /*
1524 * Else find CRL issuer: if not last certificate then issuer is next
1525 * certificate in chain.
1526 */
1527 else if (cnum < chnum)
1528 issuer = sk_X509_value(ctx->chain, cnum + 1);
1529 else {
1530 issuer = sk_X509_value(ctx->chain, chnum);
1531 /* If not self signed, can't check signature */
1532 if (!ctx->check_issued(ctx, issuer, issuer) &&
1533 !verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL_ISSUER))
1534 return 0;
1535 }
1536
1537 if (issuer == NULL)
1538 return 1;
1539
1540 /*
1541 * Skip most tests for deltas because they have already been done
1542 */
1543 if (!crl->base_crl_number) {
1544 /* Check for cRLSign bit if keyUsage present */
1545 if ((issuer->ex_flags & EXFLAG_KUSAGE) &&
1546 !(issuer->ex_kusage & KU_CRL_SIGN) &&
1547 !verify_cb_crl(ctx, X509_V_ERR_KEYUSAGE_NO_CRL_SIGN))
1548 return 0;
1549
1550 if (!(ctx->current_crl_score & CRL_SCORE_SCOPE) &&
1551 !verify_cb_crl(ctx, X509_V_ERR_DIFFERENT_CRL_SCOPE))
1552 return 0;
1553
1554 if (!(ctx->current_crl_score & CRL_SCORE_SAME_PATH) &&
1555 check_crl_path(ctx, ctx->current_issuer) <= 0 &&
1556 !verify_cb_crl(ctx, X509_V_ERR_CRL_PATH_VALIDATION_ERROR))
1557 return 0;
1558
1559 if ((crl->idp_flags & IDP_INVALID) &&
1560 !verify_cb_crl(ctx, X509_V_ERR_INVALID_EXTENSION))
1561 return 0;
1562 }
1563
1564 if (!(ctx->current_crl_score & CRL_SCORE_TIME) &&
1565 !check_crl_time(ctx, crl, 1))
1566 return 0;
1567
1568 /* Attempt to get issuer certificate public key */
1569 ikey = X509_get0_pubkey(issuer);
1570
1571 if (!ikey &&
1572 !verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY))
1573 return 0;
1574
1575 if (ikey) {
1576 int rv = X509_CRL_check_suiteb(crl, ikey, ctx->param->flags);
1577
1578 if (rv != X509_V_OK && !verify_cb_crl(ctx, rv))
1579 return 0;
1580 /* Verify CRL signature */
1581 if (X509_CRL_verify(crl, ikey) <= 0 &&
1582 !verify_cb_crl(ctx, X509_V_ERR_CRL_SIGNATURE_FAILURE))
1583 return 0;
1584 }
1585 return 1;
1586}
1587
1588/* Check certificate against CRL */
1589static int cert_crl(X509_STORE_CTX *ctx, X509_CRL *crl, X509 *x)
1590{
1591 X509_REVOKED *rev;
1592
1593 /*
1594 * The rules changed for this... previously if a CRL contained unhandled
1595 * critical extensions it could still be used to indicate a certificate
1596 * was revoked. This has since been changed since critical extensions can
1597 * change the meaning of CRL entries.
1598 */
1599 if (!(ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL)
1600 && (crl->flags & EXFLAG_CRITICAL) &&
1601 !verify_cb_crl(ctx, X509_V_ERR_UNHANDLED_CRITICAL_CRL_EXTENSION))
1602 return 0;
1603 /*
1604 * Look for serial number of certificate in CRL. If found, make sure
1605 * reason is not removeFromCRL.
1606 */
1607 if (X509_CRL_get0_by_cert(crl, &rev, x)) {
1608 if (rev->reason == CRL_REASON_REMOVE_FROM_CRL)
1609 return 2;
1610 if (!verify_cb_crl(ctx, X509_V_ERR_CERT_REVOKED))
1611 return 0;
1612 }
1613
1614 return 1;
1615}
1616
1617static int check_policy(X509_STORE_CTX *ctx)
1618{
1619 int ret;
1620
1621 if (ctx->parent)
1622 return 1;
1623 /*
1624 * With DANE, the trust anchor might be a bare public key, not a
1625 * certificate! In that case our chain does not have the trust anchor
1626 * certificate as a top-most element. This comports well with RFC5280
1627 * chain verification, since there too, the trust anchor is not part of the
1628 * chain to be verified. In particular, X509_policy_check() does not look
1629 * at the TA cert, but assumes that it is present as the top-most chain
1630 * element. We therefore temporarily push a NULL cert onto the chain if it
1631 * was verified via a bare public key, and pop it off right after the
1632 * X509_policy_check() call.
1633 */
1634 if (ctx->bare_ta_signed && !sk_X509_push(ctx->chain, NULL)) {
1635 X509err(X509_F_CHECK_POLICY, ERR_R_MALLOC_FAILURE);
1636 ctx->error = X509_V_ERR_OUT_OF_MEM;
1637 return 0;
1638 }
1639 ret = X509_policy_check(&ctx->tree, &ctx->explicit_policy, ctx->chain,
1640 ctx->param->policies, ctx->param->flags);
1641 if (ctx->bare_ta_signed)
1642 sk_X509_pop(ctx->chain);
1643
1644 if (ret == X509_PCY_TREE_INTERNAL) {
1645 X509err(X509_F_CHECK_POLICY, ERR_R_MALLOC_FAILURE);
1646 ctx->error = X509_V_ERR_OUT_OF_MEM;
1647 return 0;
1648 }
1649 /* Invalid or inconsistent extensions */
1650 if (ret == X509_PCY_TREE_INVALID) {
1651 int i;
1652
1653 /* Locate certificates with bad extensions and notify callback. */
1654 for (i = 1; i < sk_X509_num(ctx->chain); i++) {
1655 X509 *x = sk_X509_value(ctx->chain, i);
1656
1657 if (!(x->ex_flags & EXFLAG_INVALID_POLICY))
1658 continue;
1659 if (!verify_cb_cert(ctx, x, i,
1660 X509_V_ERR_INVALID_POLICY_EXTENSION))
1661 return 0;
1662 }
1663 return 1;
1664 }
1665 if (ret == X509_PCY_TREE_FAILURE) {
1666 ctx->current_cert = NULL;
1667 ctx->error = X509_V_ERR_NO_EXPLICIT_POLICY;
1668 return ctx->verify_cb(0, ctx);
1669 }
1670 if (ret != X509_PCY_TREE_VALID) {
1671 X509err(X509_F_CHECK_POLICY, ERR_R_INTERNAL_ERROR);
1672 return 0;
1673 }
1674
1675 if (ctx->param->flags & X509_V_FLAG_NOTIFY_POLICY) {
1676 ctx->current_cert = NULL;
1677 /*
1678 * Verification errors need to be "sticky", a callback may have allowed
1679 * an SSL handshake to continue despite an error, and we must then
1680 * remain in an error state. Therefore, we MUST NOT clear earlier
1681 * verification errors by setting the error to X509_V_OK.
1682 */
1683 if (!ctx->verify_cb(2, ctx))
1684 return 0;
1685 }
1686
1687 return 1;
1688}
1689
1690/*-
1691 * Check certificate validity times.
1692 * If depth >= 0, invoke verification callbacks on error, otherwise just return
1693 * the validation status.
1694 *
1695 * Return 1 on success, 0 otherwise.
1696 */
1697int x509_check_cert_time(X509_STORE_CTX *ctx, X509 *x, int depth)
1698{
1699 time_t *ptime;
1700 int i;
1701
1702 if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME)
1703 ptime = &ctx->param->check_time;
1704 else if (ctx->param->flags & X509_V_FLAG_NO_CHECK_TIME)
1705 return 1;
1706 else
1707 ptime = NULL;
1708
1709 i = X509_cmp_time(X509_get0_notBefore(x), ptime);
1710 if (i >= 0 && depth < 0)
1711 return 0;
1712 if (i == 0 && !verify_cb_cert(ctx, x, depth,
1713 X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD))
1714 return 0;
1715 if (i > 0 && !verify_cb_cert(ctx, x, depth, X509_V_ERR_CERT_NOT_YET_VALID))
1716 return 0;
1717
1718 i = X509_cmp_time(X509_get0_notAfter(x), ptime);
1719 if (i <= 0 && depth < 0)
1720 return 0;
1721 if (i == 0 && !verify_cb_cert(ctx, x, depth,
1722 X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD))
1723 return 0;
1724 if (i < 0 && !verify_cb_cert(ctx, x, depth, X509_V_ERR_CERT_HAS_EXPIRED))
1725 return 0;
1726 return 1;
1727}
1728
1729/* verify the issuer signatures and cert times of ctx->chain */
1730static int internal_verify(X509_STORE_CTX *ctx)
1731{
1732 int n = sk_X509_num(ctx->chain) - 1;
1733 X509 *xi = sk_X509_value(ctx->chain, n);
1734 X509 *xs;
1735
1736 /*
1737 * With DANE-verified bare public key TA signatures, it remains only to
1738 * check the timestamps of the top certificate. We report the issuer as
1739 * NULL, since all we have is a bare key.
1740 */
1741 if (ctx->bare_ta_signed) {
1742 xs = xi;
1743 xi = NULL;
1744 goto check_cert_time;
1745 }
1746
1747 if (ctx->check_issued(ctx, xi, xi))
1748 xs = xi; /* the typical case: last cert in the chain is self-issued */
1749 else {
1750 if (ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) {
1751 xs = xi;
1752 goto check_cert_time;
1753 }
1754 if (n <= 0) {
1755 if (!verify_cb_cert(ctx, xi, 0,
1756 X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE))
1757 return 0;
1758
1759 xs = xi;
1760 goto check_cert_time;
1761 }
1762
1763 n--;
1764 ctx->error_depth = n;
1765 xs = sk_X509_value(ctx->chain, n);
1766 }
1767
1768 /*
1769 * Do not clear ctx->error=0, it must be "sticky", only the user's callback
1770 * is allowed to reset errors (at its own peril).
1771 */
1772 while (n >= 0) {
1773 /*
1774 * For each iteration of this loop:
1775 * n is the subject depth
1776 * xs is the subject cert, for which the signature is to be checked
1777 * xi is the supposed issuer cert containing the public key to use
1778 * Initially xs == xi if the last cert in the chain is self-issued.
1779 *
1780 * Skip signature check for self-signed certificates unless explicitly
1781 * asked for because it does not add any security and just wastes time.
1782 */
1783 if (xs != xi || ((ctx->param->flags & X509_V_FLAG_CHECK_SS_SIGNATURE)
1784 && (xi->ex_flags & EXFLAG_SS) != 0)) {
1785 EVP_PKEY *pkey;
1786 /*
1787 * If the issuer's public key is not available or its key usage
1788 * does not support issuing the subject cert, report the issuer
1789 * cert and its depth (rather than n, the depth of the subject).
1790 */
1791 int issuer_depth = n + (xs == xi ? 0 : 1);
1792 /*
1793 * According to https://tools.ietf.org/html/rfc5280#section-6.1.4
1794 * step (n) we must check any given key usage extension in a CA cert
1795 * when preparing the verification of a certificate issued by it.
1796 * According to https://tools.ietf.org/html/rfc5280#section-4.2.1.3
1797 * we must not verify a certifiate signature if the key usage of the
1798 * CA certificate that issued the certificate prohibits signing.
1799 * In case the 'issuing' certificate is the last in the chain and is
1800 * not a CA certificate but a 'self-issued' end-entity cert (i.e.,
1801 * xs == xi && !(xi->ex_flags & EXFLAG_CA)) RFC 5280 does not apply
1802 * (see https://tools.ietf.org/html/rfc6818#section-2) and thus
1803 * we are free to ignore any key usage restrictions on such certs.
1804 */
1805 int ret = xs == xi && (xi->ex_flags & EXFLAG_CA) == 0
1806 ? X509_V_OK : x509_signing_allowed(xi, xs);
1807
1808 if (ret != X509_V_OK && !verify_cb_cert(ctx, xi, issuer_depth, ret))
1809 return 0;
1810 if ((pkey = X509_get0_pubkey(xi)) == NULL) {
1811 ret = X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY;
1812 if (!verify_cb_cert(ctx, xi, issuer_depth, ret))
1813 return 0;
1814 } else if (X509_verify(xs, pkey) <= 0) {
1815 ret = X509_V_ERR_CERT_SIGNATURE_FAILURE;
1816 if (!verify_cb_cert(ctx, xs, n, ret))
1817 return 0;
1818 }
1819 }
1820
1821 check_cert_time: /* in addition to RFC 5280, do also for trusted (root) cert */
1822 /* Calls verify callback as needed */
1823 if (!x509_check_cert_time(ctx, xs, n))
1824 return 0;
1825
1826 /*
1827 * Signal success at this depth. However, the previous error (if any)
1828 * is retained.
1829 */
1830 ctx->current_issuer = xi;
1831 ctx->current_cert = xs;
1832 ctx->error_depth = n;
1833 if (!ctx->verify_cb(1, ctx))
1834 return 0;
1835
1836 if (--n >= 0) {
1837 xi = xs;
1838 xs = sk_X509_value(ctx->chain, n);
1839 }
1840 }
1841 return 1;
1842}
1843
1844int X509_cmp_current_time(const ASN1_TIME *ctm)
1845{
1846 return X509_cmp_time(ctm, NULL);
1847}
1848
1849int X509_cmp_time(const ASN1_TIME *ctm, time_t *cmp_time)
1850{
1851 static const size_t utctime_length = sizeof("YYMMDDHHMMSSZ") - 1;
1852 static const size_t generalizedtime_length = sizeof("YYYYMMDDHHMMSSZ") - 1;
1853 ASN1_TIME *asn1_cmp_time = NULL;
1854 int i, day, sec, ret = 0;
1855#ifdef CHARSET_EBCDIC
1856 const char upper_z = 0x5A;
1857#else
1858 const char upper_z = 'Z';
1859#endif
1860 /*
1861 * Note that ASN.1 allows much more slack in the time format than RFC5280.
1862 * In RFC5280, the representation is fixed:
1863 * UTCTime: YYMMDDHHMMSSZ
1864 * GeneralizedTime: YYYYMMDDHHMMSSZ
1865 *
1866 * We do NOT currently enforce the following RFC 5280 requirement:
1867 * "CAs conforming to this profile MUST always encode certificate
1868 * validity dates through the year 2049 as UTCTime; certificate validity
1869 * dates in 2050 or later MUST be encoded as GeneralizedTime."
1870 */
1871 switch (ctm->type) {
1872 case V_ASN1_UTCTIME:
1873 if (ctm->length != (int)(utctime_length))
1874 return 0;
1875 break;
1876 case V_ASN1_GENERALIZEDTIME:
1877 if (ctm->length != (int)(generalizedtime_length))
1878 return 0;
1879 break;
1880 default:
1881 return 0;
1882 }
1883
1884 /**
1885 * Verify the format: the ASN.1 functions we use below allow a more
1886 * flexible format than what's mandated by RFC 5280.
1887 * Digit and date ranges will be verified in the conversion methods.
1888 */
1889 for (i = 0; i < ctm->length - 1; i++) {
1890 if (!ascii_isdigit(ctm->data[i]))
1891 return 0;
1892 }
1893 if (ctm->data[ctm->length - 1] != upper_z)
1894 return 0;
1895
1896 /*
1897 * There is ASN1_UTCTIME_cmp_time_t but no
1898 * ASN1_GENERALIZEDTIME_cmp_time_t or ASN1_TIME_cmp_time_t,
1899 * so we go through ASN.1
1900 */
1901 asn1_cmp_time = X509_time_adj(NULL, 0, cmp_time);
1902 if (asn1_cmp_time == NULL)
1903 goto err;
1904 if (!ASN1_TIME_diff(&day, &sec, ctm, asn1_cmp_time))
1905 goto err;
1906
1907 /*
1908 * X509_cmp_time comparison is <=.
1909 * The return value 0 is reserved for errors.
1910 */
1911 ret = (day >= 0 && sec >= 0) ? -1 : 1;
1912
1913 err:
1914 ASN1_TIME_free(asn1_cmp_time);
1915 return ret;
1916}
1917
1918ASN1_TIME *X509_gmtime_adj(ASN1_TIME *s, long adj)
1919{
1920 return X509_time_adj(s, adj, NULL);
1921}
1922
1923ASN1_TIME *X509_time_adj(ASN1_TIME *s, long offset_sec, time_t *in_tm)
1924{
1925 return X509_time_adj_ex(s, 0, offset_sec, in_tm);
1926}
1927
1928ASN1_TIME *X509_time_adj_ex(ASN1_TIME *s,
1929 int offset_day, long offset_sec, time_t *in_tm)
1930{
1931 time_t t;
1932
1933 if (in_tm)
1934 t = *in_tm;
1935 else
1936 time(&t);
1937
1938 if (s && !(s->flags & ASN1_STRING_FLAG_MSTRING)) {
1939 if (s->type == V_ASN1_UTCTIME)
1940 return ASN1_UTCTIME_adj(s, t, offset_day, offset_sec);
1941 if (s->type == V_ASN1_GENERALIZEDTIME)
1942 return ASN1_GENERALIZEDTIME_adj(s, t, offset_day, offset_sec);
1943 }
1944 return ASN1_TIME_adj(s, t, offset_day, offset_sec);
1945}
1946
1947int X509_get_pubkey_parameters(EVP_PKEY *pkey, STACK_OF(X509) *chain)
1948{
1949 EVP_PKEY *ktmp = NULL, *ktmp2;
1950 int i, j;
1951
1952 if ((pkey != NULL) && !EVP_PKEY_missing_parameters(pkey))
1953 return 1;
1954
1955 for (i = 0; i < sk_X509_num(chain); i++) {
1956 ktmp = X509_get0_pubkey(sk_X509_value(chain, i));
1957 if (ktmp == NULL) {
1958 X509err(X509_F_X509_GET_PUBKEY_PARAMETERS,
1959 X509_R_UNABLE_TO_GET_CERTS_PUBLIC_KEY);
1960 return 0;
1961 }
1962 if (!EVP_PKEY_missing_parameters(ktmp))
1963 break;
1964 }
1965 if (ktmp == NULL) {
1966 X509err(X509_F_X509_GET_PUBKEY_PARAMETERS,
1967 X509_R_UNABLE_TO_FIND_PARAMETERS_IN_CHAIN);
1968 return 0;
1969 }
1970
1971 /* first, populate the other certs */
1972 for (j = i - 1; j >= 0; j--) {
1973 ktmp2 = X509_get0_pubkey(sk_X509_value(chain, j));
1974 EVP_PKEY_copy_parameters(ktmp2, ktmp);
1975 }
1976
1977 if (pkey != NULL)
1978 EVP_PKEY_copy_parameters(pkey, ktmp);
1979 return 1;
1980}
1981
1982/* Make a delta CRL as the diff between two full CRLs */
1983
1984X509_CRL *X509_CRL_diff(X509_CRL *base, X509_CRL *newer,
1985 EVP_PKEY *skey, const EVP_MD *md, unsigned int flags)
1986{
1987 X509_CRL *crl = NULL;
1988 int i;
1989 STACK_OF(X509_REVOKED) *revs = NULL;
1990 /* CRLs can't be delta already */
1991 if (base->base_crl_number || newer->base_crl_number) {
1992 X509err(X509_F_X509_CRL_DIFF, X509_R_CRL_ALREADY_DELTA);
1993 return NULL;
1994 }
1995 /* Base and new CRL must have a CRL number */
1996 if (!base->crl_number || !newer->crl_number) {
1997 X509err(X509_F_X509_CRL_DIFF, X509_R_NO_CRL_NUMBER);
1998 return NULL;
1999 }
2000 /* Issuer names must match */
2001 if (X509_NAME_cmp(X509_CRL_get_issuer(base), X509_CRL_get_issuer(newer))) {
2002 X509err(X509_F_X509_CRL_DIFF, X509_R_ISSUER_MISMATCH);
2003 return NULL;
2004 }
2005 /* AKID and IDP must match */
2006 if (!crl_extension_match(base, newer, NID_authority_key_identifier)) {
2007 X509err(X509_F_X509_CRL_DIFF, X509_R_AKID_MISMATCH);
2008 return NULL;
2009 }
2010 if (!crl_extension_match(base, newer, NID_issuing_distribution_point)) {
2011 X509err(X509_F_X509_CRL_DIFF, X509_R_IDP_MISMATCH);
2012 return NULL;
2013 }
2014 /* Newer CRL number must exceed full CRL number */
2015 if (ASN1_INTEGER_cmp(newer->crl_number, base->crl_number) <= 0) {
2016 X509err(X509_F_X509_CRL_DIFF, X509_R_NEWER_CRL_NOT_NEWER);
2017 return NULL;
2018 }
2019 /* CRLs must verify */
2020 if (skey && (X509_CRL_verify(base, skey) <= 0 ||
2021 X509_CRL_verify(newer, skey) <= 0)) {
2022 X509err(X509_F_X509_CRL_DIFF, X509_R_CRL_VERIFY_FAILURE);
2023 return NULL;
2024 }
2025 /* Create new CRL */
2026 crl = X509_CRL_new();
2027 if (crl == NULL || !X509_CRL_set_version(crl, 1))
2028 goto memerr;
2029 /* Set issuer name */
2030 if (!X509_CRL_set_issuer_name(crl, X509_CRL_get_issuer(newer)))
2031 goto memerr;
2032
2033 if (!X509_CRL_set1_lastUpdate(crl, X509_CRL_get0_lastUpdate(newer)))
2034 goto memerr;
2035 if (!X509_CRL_set1_nextUpdate(crl, X509_CRL_get0_nextUpdate(newer)))
2036 goto memerr;
2037
2038 /* Set base CRL number: must be critical */
2039
2040 if (!X509_CRL_add1_ext_i2d(crl, NID_delta_crl, base->crl_number, 1, 0))
2041 goto memerr;
2042
2043 /*
2044 * Copy extensions across from newest CRL to delta: this will set CRL
2045 * number to correct value too.
2046 */
2047
2048 for (i = 0; i < X509_CRL_get_ext_count(newer); i++) {
2049 X509_EXTENSION *ext;
2050 ext = X509_CRL_get_ext(newer, i);
2051 if (!X509_CRL_add_ext(crl, ext, -1))
2052 goto memerr;
2053 }
2054
2055 /* Go through revoked entries, copying as needed */
2056
2057 revs = X509_CRL_get_REVOKED(newer);
2058
2059 for (i = 0; i < sk_X509_REVOKED_num(revs); i++) {
2060 X509_REVOKED *rvn, *rvtmp;
2061 rvn = sk_X509_REVOKED_value(revs, i);
2062 /*
2063 * Add only if not also in base. TODO: need something cleverer here
2064 * for some more complex CRLs covering multiple CAs.
2065 */
2066 if (!X509_CRL_get0_by_serial(base, &rvtmp, &rvn->serialNumber)) {
2067 rvtmp = X509_REVOKED_dup(rvn);
2068 if (!rvtmp)
2069 goto memerr;
2070 if (!X509_CRL_add0_revoked(crl, rvtmp)) {
2071 X509_REVOKED_free(rvtmp);
2072 goto memerr;
2073 }
2074 }
2075 }
2076 /* TODO: optionally prune deleted entries */
2077
2078 if (skey && md && !X509_CRL_sign(crl, skey, md))
2079 goto memerr;
2080
2081 return crl;
2082
2083 memerr:
2084 X509err(X509_F_X509_CRL_DIFF, ERR_R_MALLOC_FAILURE);
2085 X509_CRL_free(crl);
2086 return NULL;
2087}
2088
2089int X509_STORE_CTX_set_ex_data(X509_STORE_CTX *ctx, int idx, void *data)
2090{
2091 return CRYPTO_set_ex_data(&ctx->ex_data, idx, data);
2092}
2093
2094void *X509_STORE_CTX_get_ex_data(X509_STORE_CTX *ctx, int idx)
2095{
2096 return CRYPTO_get_ex_data(&ctx->ex_data, idx);
2097}
2098
2099int X509_STORE_CTX_get_error(X509_STORE_CTX *ctx)
2100{
2101 return ctx->error;
2102}
2103
2104void X509_STORE_CTX_set_error(X509_STORE_CTX *ctx, int err)
2105{
2106 ctx->error = err;
2107}
2108
2109int X509_STORE_CTX_get_error_depth(X509_STORE_CTX *ctx)
2110{
2111 return ctx->error_depth;
2112}
2113
2114void X509_STORE_CTX_set_error_depth(X509_STORE_CTX *ctx, int depth)
2115{
2116 ctx->error_depth = depth;
2117}
2118
2119X509 *X509_STORE_CTX_get_current_cert(X509_STORE_CTX *ctx)
2120{
2121 return ctx->current_cert;
2122}
2123
2124void X509_STORE_CTX_set_current_cert(X509_STORE_CTX *ctx, X509 *x)
2125{
2126 ctx->current_cert = x;
2127}
2128
2129STACK_OF(X509) *X509_STORE_CTX_get0_chain(X509_STORE_CTX *ctx)
2130{
2131 return ctx->chain;
2132}
2133
2134STACK_OF(X509) *X509_STORE_CTX_get1_chain(X509_STORE_CTX *ctx)
2135{
2136 if (!ctx->chain)
2137 return NULL;
2138 return X509_chain_up_ref(ctx->chain);
2139}
2140
2141X509 *X509_STORE_CTX_get0_current_issuer(X509_STORE_CTX *ctx)
2142{
2143 return ctx->current_issuer;
2144}
2145
2146X509_CRL *X509_STORE_CTX_get0_current_crl(X509_STORE_CTX *ctx)
2147{
2148 return ctx->current_crl;
2149}
2150
2151X509_STORE_CTX *X509_STORE_CTX_get0_parent_ctx(X509_STORE_CTX *ctx)
2152{
2153 return ctx->parent;
2154}
2155
2156void X509_STORE_CTX_set_cert(X509_STORE_CTX *ctx, X509 *x)
2157{
2158 ctx->cert = x;
2159}
2160
2161void X509_STORE_CTX_set0_crls(X509_STORE_CTX *ctx, STACK_OF(X509_CRL) *sk)
2162{
2163 ctx->crls = sk;
2164}
2165
2166int X509_STORE_CTX_set_purpose(X509_STORE_CTX *ctx, int purpose)
2167{
2168 /*
2169 * XXX: Why isn't this function always used to set the associated trust?
2170 * Should there even be a VPM->trust field at all? Or should the trust
2171 * always be inferred from the purpose by X509_STORE_CTX_init().
2172 */
2173 return X509_STORE_CTX_purpose_inherit(ctx, 0, purpose, 0);
2174}
2175
2176int X509_STORE_CTX_set_trust(X509_STORE_CTX *ctx, int trust)
2177{
2178 /*
2179 * XXX: See above, this function would only be needed when the default
2180 * trust for the purpose needs an override in a corner case.
2181 */
2182 return X509_STORE_CTX_purpose_inherit(ctx, 0, 0, trust);
2183}
2184
2185/*
2186 * This function is used to set the X509_STORE_CTX purpose and trust values.
2187 * This is intended to be used when another structure has its own trust and
2188 * purpose values which (if set) will be inherited by the ctx. If they aren't
2189 * set then we will usually have a default purpose in mind which should then
2190 * be used to set the trust value. An example of this is SSL use: an SSL
2191 * structure will have its own purpose and trust settings which the
2192 * application can set: if they aren't set then we use the default of SSL
2193 * client/server.
2194 */
2195
2196int X509_STORE_CTX_purpose_inherit(X509_STORE_CTX *ctx, int def_purpose,
2197 int purpose, int trust)
2198{
2199 int idx;
2200 /* If purpose not set use default */
2201 if (!purpose)
2202 purpose = def_purpose;
2203 /* If we have a purpose then check it is valid */
2204 if (purpose) {
2205 X509_PURPOSE *ptmp;
2206 idx = X509_PURPOSE_get_by_id(purpose);
2207 if (idx == -1) {
2208 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2209 X509_R_UNKNOWN_PURPOSE_ID);
2210 return 0;
2211 }
2212 ptmp = X509_PURPOSE_get0(idx);
2213 if (ptmp->trust == X509_TRUST_DEFAULT) {
2214 idx = X509_PURPOSE_get_by_id(def_purpose);
2215 /*
2216 * XXX: In the two callers above def_purpose is always 0, which is
2217 * not a known value, so idx will always be -1. How is the
2218 * X509_TRUST_DEFAULT case actually supposed to be handled?
2219 */
2220 if (idx == -1) {
2221 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2222 X509_R_UNKNOWN_PURPOSE_ID);
2223 return 0;
2224 }
2225 ptmp = X509_PURPOSE_get0(idx);
2226 }
2227 /* If trust not set then get from purpose default */
2228 if (!trust)
2229 trust = ptmp->trust;
2230 }
2231 if (trust) {
2232 idx = X509_TRUST_get_by_id(trust);
2233 if (idx == -1) {
2234 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2235 X509_R_UNKNOWN_TRUST_ID);
2236 return 0;
2237 }
2238 }
2239
2240 if (purpose && !ctx->param->purpose)
2241 ctx->param->purpose = purpose;
2242 if (trust && !ctx->param->trust)
2243 ctx->param->trust = trust;
2244 return 1;
2245}
2246
2247X509_STORE_CTX *X509_STORE_CTX_new(void)
2248{
2249 X509_STORE_CTX *ctx = OPENSSL_zalloc(sizeof(*ctx));
2250
2251 if (ctx == NULL) {
2252 X509err(X509_F_X509_STORE_CTX_NEW, ERR_R_MALLOC_FAILURE);
2253 return NULL;
2254 }
2255 return ctx;
2256}
2257
2258void X509_STORE_CTX_free(X509_STORE_CTX *ctx)
2259{
2260 if (ctx == NULL)
2261 return;
2262
2263 X509_STORE_CTX_cleanup(ctx);
2264 OPENSSL_free(ctx);
2265}
2266
2267int X509_STORE_CTX_init(X509_STORE_CTX *ctx, X509_STORE *store, X509 *x509,
2268 STACK_OF(X509) *chain)
2269{
2270 int ret = 1;
2271
2272 ctx->ctx = store;
2273 ctx->cert = x509;
2274 ctx->untrusted = chain;
2275 ctx->crls = NULL;
2276 ctx->num_untrusted = 0;
2277 ctx->other_ctx = NULL;
2278 ctx->valid = 0;
2279 ctx->chain = NULL;
2280 ctx->error = 0;
2281 ctx->explicit_policy = 0;
2282 ctx->error_depth = 0;
2283 ctx->current_cert = NULL;
2284 ctx->current_issuer = NULL;
2285 ctx->current_crl = NULL;
2286 ctx->current_crl_score = 0;
2287 ctx->current_reasons = 0;
2288 ctx->tree = NULL;
2289 ctx->parent = NULL;
2290 ctx->dane = NULL;
2291 ctx->bare_ta_signed = 0;
2292 /* Zero ex_data to make sure we're cleanup-safe */
2293 memset(&ctx->ex_data, 0, sizeof(ctx->ex_data));
2294
2295 /* store->cleanup is always 0 in OpenSSL, if set must be idempotent */
2296 if (store)
2297 ctx->cleanup = store->cleanup;
2298 else
2299 ctx->cleanup = 0;
2300
2301 if (store && store->check_issued)
2302 ctx->check_issued = store->check_issued;
2303 else
2304 ctx->check_issued = check_issued;
2305
2306 if (store && store->get_issuer)
2307 ctx->get_issuer = store->get_issuer;
2308 else
2309 ctx->get_issuer = X509_STORE_CTX_get1_issuer;
2310
2311 if (store && store->verify_cb)
2312 ctx->verify_cb = store->verify_cb;
2313 else
2314 ctx->verify_cb = null_callback;
2315
2316 if (store && store->verify)
2317 ctx->verify = store->verify;
2318 else
2319 ctx->verify = internal_verify;
2320
2321 if (store && store->check_revocation)
2322 ctx->check_revocation = store->check_revocation;
2323 else
2324 ctx->check_revocation = check_revocation;
2325
2326 if (store && store->get_crl)
2327 ctx->get_crl = store->get_crl;
2328 else
2329 ctx->get_crl = NULL;
2330
2331 if (store && store->check_crl)
2332 ctx->check_crl = store->check_crl;
2333 else
2334 ctx->check_crl = check_crl;
2335
2336 if (store && store->cert_crl)
2337 ctx->cert_crl = store->cert_crl;
2338 else
2339 ctx->cert_crl = cert_crl;
2340
2341 if (store && store->check_policy)
2342 ctx->check_policy = store->check_policy;
2343 else
2344 ctx->check_policy = check_policy;
2345
2346 if (store && store->lookup_certs)
2347 ctx->lookup_certs = store->lookup_certs;
2348 else
2349 ctx->lookup_certs = X509_STORE_CTX_get1_certs;
2350
2351 if (store && store->lookup_crls)
2352 ctx->lookup_crls = store->lookup_crls;
2353 else
2354 ctx->lookup_crls = X509_STORE_CTX_get1_crls;
2355
2356 ctx->param = X509_VERIFY_PARAM_new();
2357 if (ctx->param == NULL) {
2358 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2359 goto err;
2360 }
2361
2362 /*
2363 * Inherit callbacks and flags from X509_STORE if not set use defaults.
2364 */
2365 if (store)
2366 ret = X509_VERIFY_PARAM_inherit(ctx->param, store->param);
2367 else
2368 ctx->param->inh_flags |= X509_VP_FLAG_DEFAULT | X509_VP_FLAG_ONCE;
2369
2370 if (ret)
2371 ret = X509_VERIFY_PARAM_inherit(ctx->param,
2372 X509_VERIFY_PARAM_lookup("default"));
2373
2374 if (ret == 0) {
2375 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2376 goto err;
2377 }
2378
2379 /*
2380 * XXX: For now, continue to inherit trust from VPM, but infer from the
2381 * purpose if this still yields the default value.
2382 */
2383 if (ctx->param->trust == X509_TRUST_DEFAULT) {
2384 int idx = X509_PURPOSE_get_by_id(ctx->param->purpose);
2385 X509_PURPOSE *xp = X509_PURPOSE_get0(idx);
2386
2387 if (xp != NULL)
2388 ctx->param->trust = X509_PURPOSE_get_trust(xp);
2389 }
2390
2391 if (CRYPTO_new_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx,
2392 &ctx->ex_data))
2393 return 1;
2394 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2395
2396 err:
2397 /*
2398 * On error clean up allocated storage, if the store context was not
2399 * allocated with X509_STORE_CTX_new() this is our last chance to do so.
2400 */
2401 X509_STORE_CTX_cleanup(ctx);
2402 return 0;
2403}
2404
2405/*
2406 * Set alternative lookup method: just a STACK of trusted certificates. This
2407 * avoids X509_STORE nastiness where it isn't needed.
2408 */
2409void X509_STORE_CTX_set0_trusted_stack(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2410{
2411 ctx->other_ctx = sk;
2412 ctx->get_issuer = get_issuer_sk;
2413 ctx->lookup_certs = lookup_certs_sk;
2414}
2415
2416void X509_STORE_CTX_cleanup(X509_STORE_CTX *ctx)
2417{
2418 /*
2419 * We need to be idempotent because, unfortunately, free() also calls
2420 * cleanup(), so the natural call sequence new(), init(), cleanup(), free()
2421 * calls cleanup() for the same object twice! Thus we must zero the
2422 * pointers below after they're freed!
2423 */
2424 /* Seems to always be 0 in OpenSSL, do this at most once. */
2425 if (ctx->cleanup != NULL) {
2426 ctx->cleanup(ctx);
2427 ctx->cleanup = NULL;
2428 }
2429 if (ctx->param != NULL) {
2430 if (ctx->parent == NULL)
2431 X509_VERIFY_PARAM_free(ctx->param);
2432 ctx->param = NULL;
2433 }
2434 X509_policy_tree_free(ctx->tree);
2435 ctx->tree = NULL;
2436 sk_X509_pop_free(ctx->chain, X509_free);
2437 ctx->chain = NULL;
2438 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx, &(ctx->ex_data));
2439 memset(&ctx->ex_data, 0, sizeof(ctx->ex_data));
2440}
2441
2442void X509_STORE_CTX_set_depth(X509_STORE_CTX *ctx, int depth)
2443{
2444 X509_VERIFY_PARAM_set_depth(ctx->param, depth);
2445}
2446
2447void X509_STORE_CTX_set_flags(X509_STORE_CTX *ctx, unsigned long flags)
2448{
2449 X509_VERIFY_PARAM_set_flags(ctx->param, flags);
2450}
2451
2452void X509_STORE_CTX_set_time(X509_STORE_CTX *ctx, unsigned long flags,
2453 time_t t)
2454{
2455 X509_VERIFY_PARAM_set_time(ctx->param, t);
2456}
2457
2458X509 *X509_STORE_CTX_get0_cert(X509_STORE_CTX *ctx)
2459{
2460 return ctx->cert;
2461}
2462
2463STACK_OF(X509) *X509_STORE_CTX_get0_untrusted(X509_STORE_CTX *ctx)
2464{
2465 return ctx->untrusted;
2466}
2467
2468void X509_STORE_CTX_set0_untrusted(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2469{
2470 ctx->untrusted = sk;
2471}
2472
2473void X509_STORE_CTX_set0_verified_chain(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2474{
2475 sk_X509_pop_free(ctx->chain, X509_free);
2476 ctx->chain = sk;
2477}
2478
2479void X509_STORE_CTX_set_verify_cb(X509_STORE_CTX *ctx,
2480 X509_STORE_CTX_verify_cb verify_cb)
2481{
2482 ctx->verify_cb = verify_cb;
2483}
2484
2485X509_STORE_CTX_verify_cb X509_STORE_CTX_get_verify_cb(X509_STORE_CTX *ctx)
2486{
2487 return ctx->verify_cb;
2488}
2489
2490void X509_STORE_CTX_set_verify(X509_STORE_CTX *ctx,
2491 X509_STORE_CTX_verify_fn verify)
2492{
2493 ctx->verify = verify;
2494}
2495
2496X509_STORE_CTX_verify_fn X509_STORE_CTX_get_verify(X509_STORE_CTX *ctx)
2497{
2498 return ctx->verify;
2499}
2500
2501X509_STORE_CTX_get_issuer_fn X509_STORE_CTX_get_get_issuer(X509_STORE_CTX *ctx)
2502{
2503 return ctx->get_issuer;
2504}
2505
2506X509_STORE_CTX_check_issued_fn X509_STORE_CTX_get_check_issued(X509_STORE_CTX *ctx)
2507{
2508 return ctx->check_issued;
2509}
2510
2511X509_STORE_CTX_check_revocation_fn X509_STORE_CTX_get_check_revocation(X509_STORE_CTX *ctx)
2512{
2513 return ctx->check_revocation;
2514}
2515
2516X509_STORE_CTX_get_crl_fn X509_STORE_CTX_get_get_crl(X509_STORE_CTX *ctx)
2517{
2518 return ctx->get_crl;
2519}
2520
2521X509_STORE_CTX_check_crl_fn X509_STORE_CTX_get_check_crl(X509_STORE_CTX *ctx)
2522{
2523 return ctx->check_crl;
2524}
2525
2526X509_STORE_CTX_cert_crl_fn X509_STORE_CTX_get_cert_crl(X509_STORE_CTX *ctx)
2527{
2528 return ctx->cert_crl;
2529}
2530
2531X509_STORE_CTX_check_policy_fn X509_STORE_CTX_get_check_policy(X509_STORE_CTX *ctx)
2532{
2533 return ctx->check_policy;
2534}
2535
2536X509_STORE_CTX_lookup_certs_fn X509_STORE_CTX_get_lookup_certs(X509_STORE_CTX *ctx)
2537{
2538 return ctx->lookup_certs;
2539}
2540
2541X509_STORE_CTX_lookup_crls_fn X509_STORE_CTX_get_lookup_crls(X509_STORE_CTX *ctx)
2542{
2543 return ctx->lookup_crls;
2544}
2545
2546X509_STORE_CTX_cleanup_fn X509_STORE_CTX_get_cleanup(X509_STORE_CTX *ctx)
2547{
2548 return ctx->cleanup;
2549}
2550
2551X509_POLICY_TREE *X509_STORE_CTX_get0_policy_tree(X509_STORE_CTX *ctx)
2552{
2553 return ctx->tree;
2554}
2555
2556int X509_STORE_CTX_get_explicit_policy(X509_STORE_CTX *ctx)
2557{
2558 return ctx->explicit_policy;
2559}
2560
2561int X509_STORE_CTX_get_num_untrusted(X509_STORE_CTX *ctx)
2562{
2563 return ctx->num_untrusted;
2564}
2565
2566int X509_STORE_CTX_set_default(X509_STORE_CTX *ctx, const char *name)
2567{
2568 const X509_VERIFY_PARAM *param;
2569 param = X509_VERIFY_PARAM_lookup(name);
2570 if (!param)
2571 return 0;
2572 return X509_VERIFY_PARAM_inherit(ctx->param, param);
2573}
2574
2575X509_VERIFY_PARAM *X509_STORE_CTX_get0_param(X509_STORE_CTX *ctx)
2576{
2577 return ctx->param;
2578}
2579
2580void X509_STORE_CTX_set0_param(X509_STORE_CTX *ctx, X509_VERIFY_PARAM *param)
2581{
2582 X509_VERIFY_PARAM_free(ctx->param);
2583 ctx->param = param;
2584}
2585
2586void X509_STORE_CTX_set0_dane(X509_STORE_CTX *ctx, SSL_DANE *dane)
2587{
2588 ctx->dane = dane;
2589}
2590
2591static unsigned char *dane_i2d(
2592 X509 *cert,
2593 uint8_t selector,
2594 unsigned int *i2dlen)
2595{
2596 unsigned char *buf = NULL;
2597 int len;
2598
2599 /*
2600 * Extract ASN.1 DER form of certificate or public key.
2601 */
2602 switch (selector) {
2603 case DANETLS_SELECTOR_CERT:
2604 len = i2d_X509(cert, &buf);
2605 break;
2606 case DANETLS_SELECTOR_SPKI:
2607 len = i2d_X509_PUBKEY(X509_get_X509_PUBKEY(cert), &buf);
2608 break;
2609 default:
2610 X509err(X509_F_DANE_I2D, X509_R_BAD_SELECTOR);
2611 return NULL;
2612 }
2613
2614 if (len < 0 || buf == NULL) {
2615 X509err(X509_F_DANE_I2D, ERR_R_MALLOC_FAILURE);
2616 return NULL;
2617 }
2618
2619 *i2dlen = (unsigned int)len;
2620 return buf;
2621}
2622
2623#define DANETLS_NONE 256 /* impossible uint8_t */
2624
2625static int dane_match(X509_STORE_CTX *ctx, X509 *cert, int depth)
2626{
2627 SSL_DANE *dane = ctx->dane;
2628 unsigned usage = DANETLS_NONE;
2629 unsigned selector = DANETLS_NONE;
2630 unsigned ordinal = DANETLS_NONE;
2631 unsigned mtype = DANETLS_NONE;
2632 unsigned char *i2dbuf = NULL;
2633 unsigned int i2dlen = 0;
2634 unsigned char mdbuf[EVP_MAX_MD_SIZE];
2635 unsigned char *cmpbuf = NULL;
2636 unsigned int cmplen = 0;
2637 int i;
2638 int recnum;
2639 int matched = 0;
2640 danetls_record *t = NULL;
2641 uint32_t mask;
2642
2643 mask = (depth == 0) ? DANETLS_EE_MASK : DANETLS_TA_MASK;
2644
2645 /*
2646 * The trust store is not applicable with DANE-TA(2)
2647 */
2648 if (depth >= ctx->num_untrusted)
2649 mask &= DANETLS_PKIX_MASK;
2650
2651 /*
2652 * If we've previously matched a PKIX-?? record, no need to test any
2653 * further PKIX-?? records, it remains to just build the PKIX chain.
2654 * Had the match been a DANE-?? record, we'd be done already.
2655 */
2656 if (dane->mdpth >= 0)
2657 mask &= ~DANETLS_PKIX_MASK;
2658
2659 /*-
2660 * https://tools.ietf.org/html/rfc7671#section-5.1
2661 * https://tools.ietf.org/html/rfc7671#section-5.2
2662 * https://tools.ietf.org/html/rfc7671#section-5.3
2663 * https://tools.ietf.org/html/rfc7671#section-5.4
2664 *
2665 * We handle DANE-EE(3) records first as they require no chain building
2666 * and no expiration or hostname checks. We also process digests with
2667 * higher ordinals first and ignore lower priorities except Full(0) which
2668 * is always processed (last). If none match, we then process PKIX-EE(1).
2669 *
2670 * NOTE: This relies on DANE usages sorting before the corresponding PKIX
2671 * usages in SSL_dane_tlsa_add(), and also on descending sorting of digest
2672 * priorities. See twin comment in ssl/ssl_lib.c.
2673 *
2674 * We expect that most TLSA RRsets will have just a single usage, so we
2675 * don't go out of our way to cache multiple selector-specific i2d buffers
2676 * across usages, but if the selector happens to remain the same as switch
2677 * usages, that's OK. Thus, a set of "3 1 1", "3 0 1", "1 1 1", "1 0 1",
2678 * records would result in us generating each of the certificate and public
2679 * key DER forms twice, but more typically we'd just see multiple "3 1 1"
2680 * or multiple "3 0 1" records.
2681 *
2682 * As soon as we find a match at any given depth, we stop, because either
2683 * we've matched a DANE-?? record and the peer is authenticated, or, after
2684 * exhausting all DANE-?? records, we've matched a PKIX-?? record, which is
2685 * sufficient for DANE, and what remains to do is ordinary PKIX validation.
2686 */
2687 recnum = (dane->umask & mask) ? sk_danetls_record_num(dane->trecs) : 0;
2688 for (i = 0; matched == 0 && i < recnum; ++i) {
2689 t = sk_danetls_record_value(dane->trecs, i);
2690 if ((DANETLS_USAGE_BIT(t->usage) & mask) == 0)
2691 continue;
2692 if (t->usage != usage) {
2693 usage = t->usage;
2694
2695 /* Reset digest agility for each usage/selector pair */
2696 mtype = DANETLS_NONE;
2697 ordinal = dane->dctx->mdord[t->mtype];
2698 }
2699 if (t->selector != selector) {
2700 selector = t->selector;
2701
2702 /* Update per-selector state */
2703 OPENSSL_free(i2dbuf);
2704 i2dbuf = dane_i2d(cert, selector, &i2dlen);
2705 if (i2dbuf == NULL)
2706 return -1;
2707
2708 /* Reset digest agility for each usage/selector pair */
2709 mtype = DANETLS_NONE;
2710 ordinal = dane->dctx->mdord[t->mtype];
2711 } else if (t->mtype != DANETLS_MATCHING_FULL) {
2712 /*-
2713 * Digest agility:
2714 *
2715 * <https://tools.ietf.org/html/rfc7671#section-9>
2716 *
2717 * For a fixed selector, after processing all records with the
2718 * highest mtype ordinal, ignore all mtypes with lower ordinals
2719 * other than "Full".
2720 */
2721 if (dane->dctx->mdord[t->mtype] < ordinal)
2722 continue;
2723 }
2724
2725 /*
2726 * Each time we hit a (new selector or) mtype, re-compute the relevant
2727 * digest, more complex caching is not worth the code space.
2728 */
2729 if (t->mtype != mtype) {
2730 const EVP_MD *md = dane->dctx->mdevp[mtype = t->mtype];
2731 cmpbuf = i2dbuf;
2732 cmplen = i2dlen;
2733
2734 if (md != NULL) {
2735 cmpbuf = mdbuf;
2736 if (!EVP_Digest(i2dbuf, i2dlen, cmpbuf, &cmplen, md, 0)) {
2737 matched = -1;
2738 break;
2739 }
2740 }
2741 }
2742
2743 /*
2744 * Squirrel away the certificate and depth if we have a match. Any
2745 * DANE match is dispositive, but with PKIX we still need to build a
2746 * full chain.
2747 */
2748 if (cmplen == t->dlen &&
2749 memcmp(cmpbuf, t->data, cmplen) == 0) {
2750 if (DANETLS_USAGE_BIT(usage) & DANETLS_DANE_MASK)
2751 matched = 1;
2752 if (matched || dane->mdpth < 0) {
2753 dane->mdpth = depth;
2754 dane->mtlsa = t;
2755 OPENSSL_free(dane->mcert);
2756 dane->mcert = cert;
2757 X509_up_ref(cert);
2758 }
2759 break;
2760 }
2761 }
2762
2763 /* Clear the one-element DER cache */
2764 OPENSSL_free(i2dbuf);
2765 return matched;
2766}
2767
2768static int check_dane_issuer(X509_STORE_CTX *ctx, int depth)
2769{
2770 SSL_DANE *dane = ctx->dane;
2771 int matched = 0;
2772 X509 *cert;
2773
2774 if (!DANETLS_HAS_TA(dane) || depth == 0)
2775 return X509_TRUST_UNTRUSTED;
2776
2777 /*
2778 * Record any DANE trust-anchor matches, for the first depth to test, if
2779 * there's one at that depth. (This'll be false for length 1 chains looking
2780 * for an exact match for the leaf certificate).
2781 */
2782 cert = sk_X509_value(ctx->chain, depth);
2783 if (cert != NULL && (matched = dane_match(ctx, cert, depth)) < 0)
2784 return X509_TRUST_REJECTED;
2785 if (matched > 0) {
2786 ctx->num_untrusted = depth - 1;
2787 return X509_TRUST_TRUSTED;
2788 }
2789
2790 return X509_TRUST_UNTRUSTED;
2791}
2792
2793static int check_dane_pkeys(X509_STORE_CTX *ctx)
2794{
2795 SSL_DANE *dane = ctx->dane;
2796 danetls_record *t;
2797 int num = ctx->num_untrusted;
2798 X509 *cert = sk_X509_value(ctx->chain, num - 1);
2799 int recnum = sk_danetls_record_num(dane->trecs);
2800 int i;
2801
2802 for (i = 0; i < recnum; ++i) {
2803 t = sk_danetls_record_value(dane->trecs, i);
2804 if (t->usage != DANETLS_USAGE_DANE_TA ||
2805 t->selector != DANETLS_SELECTOR_SPKI ||
2806 t->mtype != DANETLS_MATCHING_FULL ||
2807 X509_verify(cert, t->spki) <= 0)
2808 continue;
2809
2810 /* Clear any PKIX-?? matches that failed to extend to a full chain */
2811 X509_free(dane->mcert);
2812 dane->mcert = NULL;
2813
2814 /* Record match via a bare TA public key */
2815 ctx->bare_ta_signed = 1;
2816 dane->mdpth = num - 1;
2817 dane->mtlsa = t;
2818
2819 /* Prune any excess chain certificates */
2820 num = sk_X509_num(ctx->chain);
2821 for (; num > ctx->num_untrusted; --num)
2822 X509_free(sk_X509_pop(ctx->chain));
2823
2824 return X509_TRUST_TRUSTED;
2825 }
2826
2827 return X509_TRUST_UNTRUSTED;
2828}
2829
2830static void dane_reset(SSL_DANE *dane)
2831{
2832 /*
2833 * Reset state to verify another chain, or clear after failure.
2834 */
2835 X509_free(dane->mcert);
2836 dane->mcert = NULL;
2837 dane->mtlsa = NULL;
2838 dane->mdpth = -1;
2839 dane->pdpth = -1;
2840}
2841
2842static int check_leaf_suiteb(X509_STORE_CTX *ctx, X509 *cert)
2843{
2844 int err = X509_chain_check_suiteb(NULL, cert, NULL, ctx->param->flags);
2845
2846 if (err == X509_V_OK)
2847 return 1;
2848 return verify_cb_cert(ctx, cert, 0, err);
2849}
2850
2851static int dane_verify(X509_STORE_CTX *ctx)
2852{
2853 X509 *cert = ctx->cert;
2854 SSL_DANE *dane = ctx->dane;
2855 int matched;
2856 int done;
2857
2858 dane_reset(dane);
2859
2860 /*-
2861 * When testing the leaf certificate, if we match a DANE-EE(3) record,
2862 * dane_match() returns 1 and we're done. If however we match a PKIX-EE(1)
2863 * record, the match depth and matching TLSA record are recorded, but the
2864 * return value is 0, because we still need to find a PKIX trust-anchor.
2865 * Therefore, when DANE authentication is enabled (required), we're done
2866 * if:
2867 * + matched < 0, internal error.
2868 * + matched == 1, we matched a DANE-EE(3) record
2869 * + matched == 0, mdepth < 0 (no PKIX-EE match) and there are no
2870 * DANE-TA(2) or PKIX-TA(0) to test.
2871 */
2872 matched = dane_match(ctx, ctx->cert, 0);
2873 done = matched != 0 || (!DANETLS_HAS_TA(dane) && dane->mdpth < 0);
2874
2875 if (done)
2876 X509_get_pubkey_parameters(NULL, ctx->chain);
2877
2878 if (matched > 0) {
2879 /* Callback invoked as needed */
2880 if (!check_leaf_suiteb(ctx, cert))
2881 return 0;
2882 /* Callback invoked as needed */
2883 if ((dane->flags & DANE_FLAG_NO_DANE_EE_NAMECHECKS) == 0 &&
2884 !check_id(ctx))
2885 return 0;
2886 /* Bypass internal_verify(), issue depth 0 success callback */
2887 ctx->error_depth = 0;
2888 ctx->current_cert = cert;
2889 return ctx->verify_cb(1, ctx);
2890 }
2891
2892 if (matched < 0) {
2893 ctx->error_depth = 0;
2894 ctx->current_cert = cert;
2895 ctx->error = X509_V_ERR_OUT_OF_MEM;
2896 return -1;
2897 }
2898
2899 if (done) {
2900 /* Fail early, TA-based success is not possible */
2901 if (!check_leaf_suiteb(ctx, cert))
2902 return 0;
2903 return verify_cb_cert(ctx, cert, 0, X509_V_ERR_DANE_NO_MATCH);
2904 }
2905
2906 /*
2907 * Chain verification for usages 0/1/2. TLSA record matching of depth > 0
2908 * certificates happens in-line with building the rest of the chain.
2909 */
2910 return verify_chain(ctx);
2911}
2912
2913/* Get issuer, without duplicate suppression */
2914static int get_issuer(X509 **issuer, X509_STORE_CTX *ctx, X509 *cert)
2915{
2916 STACK_OF(X509) *saved_chain = ctx->chain;
2917 int ok;
2918
2919 ctx->chain = NULL;
2920 ok = ctx->get_issuer(issuer, ctx, cert);
2921 ctx->chain = saved_chain;
2922
2923 return ok;
2924}
2925
2926static int build_chain(X509_STORE_CTX *ctx)
2927{
2928 SSL_DANE *dane = ctx->dane;
2929 int num = sk_X509_num(ctx->chain);
2930 X509 *cert = sk_X509_value(ctx->chain, num - 1);
2931 int ss = cert_self_signed(cert);
2932 STACK_OF(X509) *sktmp = NULL;
2933 unsigned int search;
2934 int may_trusted = 0;
2935 int may_alternate = 0;
2936 int trust = X509_TRUST_UNTRUSTED;
2937 int alt_untrusted = 0;
2938 int depth;
2939 int ok = 0;
2940 int i;
2941
2942 /* Our chain starts with a single untrusted element. */
2943 if (!ossl_assert(num == 1 && ctx->num_untrusted == num)) {
2944 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
2945 ctx->error = X509_V_ERR_UNSPECIFIED;
2946 return 0;
2947 }
2948
2949#define S_DOUNTRUSTED (1 << 0) /* Search untrusted chain */
2950#define S_DOTRUSTED (1 << 1) /* Search trusted store */
2951#define S_DOALTERNATE (1 << 2) /* Retry with pruned alternate chain */
2952 /*
2953 * Set up search policy, untrusted if possible, trusted-first if enabled.
2954 * If we're doing DANE and not doing PKIX-TA/PKIX-EE, we never look in the
2955 * trust_store, otherwise we might look there first. If not trusted-first,
2956 * and alternate chains are not disabled, try building an alternate chain
2957 * if no luck with untrusted first.
2958 */
2959 search = (ctx->untrusted != NULL) ? S_DOUNTRUSTED : 0;
2960 if (DANETLS_HAS_PKIX(dane) || !DANETLS_HAS_DANE(dane)) {
2961 if (search == 0 || ctx->param->flags & X509_V_FLAG_TRUSTED_FIRST)
2962 search |= S_DOTRUSTED;
2963 else if (!(ctx->param->flags & X509_V_FLAG_NO_ALT_CHAINS))
2964 may_alternate = 1;
2965 may_trusted = 1;
2966 }
2967
2968 /*
2969 * Shallow-copy the stack of untrusted certificates (with TLS, this is
2970 * typically the content of the peer's certificate message) so can make
2971 * multiple passes over it, while free to remove elements as we go.
2972 */
2973 if (ctx->untrusted && (sktmp = sk_X509_dup(ctx->untrusted)) == NULL) {
2974 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2975 ctx->error = X509_V_ERR_OUT_OF_MEM;
2976 return 0;
2977 }
2978
2979 /*
2980 * If we got any "DANE-TA(2) Cert(0) Full(0)" trust-anchors from DNS, add
2981 * them to our working copy of the untrusted certificate stack. Since the
2982 * caller of X509_STORE_CTX_init() may have provided only a leaf cert with
2983 * no corresponding stack of untrusted certificates, we may need to create
2984 * an empty stack first. [ At present only the ssl library provides DANE
2985 * support, and ssl_verify_cert_chain() always provides a non-null stack
2986 * containing at least the leaf certificate, but we must be prepared for
2987 * this to change. ]
2988 */
2989 if (DANETLS_ENABLED(dane) && dane->certs != NULL) {
2990 if (sktmp == NULL && (sktmp = sk_X509_new_null()) == NULL) {
2991 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2992 ctx->error = X509_V_ERR_OUT_OF_MEM;
2993 return 0;
2994 }
2995 for (i = 0; i < sk_X509_num(dane->certs); ++i) {
2996 if (!sk_X509_push(sktmp, sk_X509_value(dane->certs, i))) {
2997 sk_X509_free(sktmp);
2998 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2999 ctx->error = X509_V_ERR_OUT_OF_MEM;
3000 return 0;
3001 }
3002 }
3003 }
3004
3005 /*
3006 * Still absurdly large, but arithmetically safe, a lower hard upper bound
3007 * might be reasonable.
3008 */
3009 if (ctx->param->depth > INT_MAX/2)
3010 ctx->param->depth = INT_MAX/2;
3011
3012 /*
3013 * Try to Extend the chain until we reach an ultimately trusted issuer.
3014 * Build chains up to one longer the limit, later fail if we hit the limit,
3015 * with an X509_V_ERR_CERT_CHAIN_TOO_LONG error code.
3016 */
3017 depth = ctx->param->depth + 1;
3018
3019 while (search != 0) {
3020 X509 *x;
3021 X509 *xtmp = NULL;
3022
3023 /*
3024 * Look in the trust store if enabled for first lookup, or we've run
3025 * out of untrusted issuers and search here is not disabled. When we
3026 * reach the depth limit, we stop extending the chain, if by that point
3027 * we've not found a trust-anchor, any trusted chain would be too long.
3028 *
3029 * The error reported to the application verify callback is at the
3030 * maximal valid depth with the current certificate equal to the last
3031 * not ultimately-trusted issuer. For example, with verify_depth = 0,
3032 * the callback will report errors at depth=1 when the immediate issuer
3033 * of the leaf certificate is not a trust anchor. No attempt will be
3034 * made to locate an issuer for that certificate, since such a chain
3035 * would be a-priori too long.
3036 */
3037 if ((search & S_DOTRUSTED) != 0) {
3038 i = num = sk_X509_num(ctx->chain);
3039 if ((search & S_DOALTERNATE) != 0) {
3040 /*
3041 * As high up the chain as we can, look for an alternative
3042 * trusted issuer of an untrusted certificate that currently
3043 * has an untrusted issuer. We use the alt_untrusted variable
3044 * to track how far up the chain we find the first match. It
3045 * is only if and when we find a match, that we prune the chain
3046 * and reset ctx->num_untrusted to the reduced count of
3047 * untrusted certificates. While we're searching for such a
3048 * match (which may never be found), it is neither safe nor
3049 * wise to preemptively modify either the chain or
3050 * ctx->num_untrusted.
3051 *
3052 * Note, like ctx->num_untrusted, alt_untrusted is a count of
3053 * untrusted certificates, not a "depth".
3054 */
3055 i = alt_untrusted;
3056 }
3057 x = sk_X509_value(ctx->chain, i-1);
3058
3059 ok = (depth < num) ? 0 : get_issuer(&xtmp, ctx, x);
3060
3061 if (ok < 0) {
3062 trust = X509_TRUST_REJECTED;
3063 ctx->error = X509_V_ERR_STORE_LOOKUP;
3064 search = 0;
3065 continue;
3066 }
3067
3068 if (ok > 0) {
3069 /*
3070 * Alternative trusted issuer for a mid-chain untrusted cert?
3071 * Pop the untrusted cert's successors and retry. We might now
3072 * be able to complete a valid chain via the trust store. Note
3073 * that despite the current trust-store match we might still
3074 * fail complete the chain to a suitable trust-anchor, in which
3075 * case we may prune some more untrusted certificates and try
3076 * again. Thus the S_DOALTERNATE bit may yet be turned on
3077 * again with an even shorter untrusted chain!
3078 *
3079 * If in the process we threw away our matching PKIX-TA trust
3080 * anchor, reset DANE trust. We might find a suitable trusted
3081 * certificate among the ones from the trust store.
3082 */
3083 if ((search & S_DOALTERNATE) != 0) {
3084 if (!ossl_assert(num > i && i > 0 && ss == 0)) {
3085 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
3086 X509_free(xtmp);
3087 trust = X509_TRUST_REJECTED;
3088 ctx->error = X509_V_ERR_UNSPECIFIED;
3089 search = 0;
3090 continue;
3091 }
3092 search &= ~S_DOALTERNATE;
3093 for (; num > i; --num)
3094 X509_free(sk_X509_pop(ctx->chain));
3095 ctx->num_untrusted = num;
3096
3097 if (DANETLS_ENABLED(dane) &&
3098 dane->mdpth >= ctx->num_untrusted) {
3099 dane->mdpth = -1;
3100 X509_free(dane->mcert);
3101 dane->mcert = NULL;
3102 }
3103 if (DANETLS_ENABLED(dane) &&
3104 dane->pdpth >= ctx->num_untrusted)
3105 dane->pdpth = -1;
3106 }
3107
3108 /*
3109 * Self-signed untrusted certificates get replaced by their
3110 * trusted matching issuer. Otherwise, grow the chain.
3111 */
3112 if (ss == 0) {
3113 if (!sk_X509_push(ctx->chain, x = xtmp)) {
3114 X509_free(xtmp);
3115 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
3116 trust = X509_TRUST_REJECTED;
3117 ctx->error = X509_V_ERR_OUT_OF_MEM;
3118 search = 0;
3119 continue;
3120 }
3121 ss = cert_self_signed(x);
3122 } else if (num == ctx->num_untrusted) {
3123 /*
3124 * We have a self-signed certificate that has the same
3125 * subject name (and perhaps keyid and/or serial number) as
3126 * a trust-anchor. We must have an exact match to avoid
3127 * possible impersonation via key substitution etc.
3128 */
3129 if (X509_cmp(x, xtmp) != 0) {
3130 /* Self-signed untrusted mimic. */
3131 X509_free(xtmp);
3132 ok = 0;
3133 } else {
3134 X509_free(x);
3135 ctx->num_untrusted = --num;
3136 (void) sk_X509_set(ctx->chain, num, x = xtmp);
3137 }
3138 }
3139
3140 /*
3141 * We've added a new trusted certificate to the chain, recheck
3142 * trust. If not done, and not self-signed look deeper.
3143 * Whether or not we're doing "trusted first", we no longer
3144 * look for untrusted certificates from the peer's chain.
3145 *
3146 * At this point ctx->num_trusted and num must reflect the
3147 * correct number of untrusted certificates, since the DANE
3148 * logic in check_trust() depends on distinguishing CAs from
3149 * "the wire" from CAs from the trust store. In particular, the
3150 * certificate at depth "num" should be the new trusted
3151 * certificate with ctx->num_untrusted <= num.
3152 */
3153 if (ok) {
3154 if (!ossl_assert(ctx->num_untrusted <= num)) {
3155 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
3156 trust = X509_TRUST_REJECTED;
3157 ctx->error = X509_V_ERR_UNSPECIFIED;
3158 search = 0;
3159 continue;
3160 }
3161 search &= ~S_DOUNTRUSTED;
3162 switch (trust = check_trust(ctx, num)) {
3163 case X509_TRUST_TRUSTED:
3164 case X509_TRUST_REJECTED:
3165 search = 0;
3166 continue;
3167 }
3168 if (ss == 0)
3169 continue;
3170 }
3171 }
3172
3173 /*
3174 * No dispositive decision, and either self-signed or no match, if
3175 * we were doing untrusted-first, and alt-chains are not disabled,
3176 * do that, by repeatedly losing one untrusted element at a time,
3177 * and trying to extend the shorted chain.
3178 */
3179 if ((search & S_DOUNTRUSTED) == 0) {
3180 /* Continue search for a trusted issuer of a shorter chain? */
3181 if ((search & S_DOALTERNATE) != 0 && --alt_untrusted > 0)
3182 continue;
3183 /* Still no luck and no fallbacks left? */
3184 if (!may_alternate || (search & S_DOALTERNATE) != 0 ||
3185 ctx->num_untrusted < 2)
3186 break;
3187 /* Search for a trusted issuer of a shorter chain */
3188 search |= S_DOALTERNATE;
3189 alt_untrusted = ctx->num_untrusted - 1;
3190 ss = 0;
3191 }
3192 }
3193
3194 /*
3195 * Extend chain with peer-provided certificates
3196 */
3197 if ((search & S_DOUNTRUSTED) != 0) {
3198 num = sk_X509_num(ctx->chain);
3199 if (!ossl_assert(num == ctx->num_untrusted)) {
3200 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
3201 trust = X509_TRUST_REJECTED;
3202 ctx->error = X509_V_ERR_UNSPECIFIED;
3203 search = 0;
3204 continue;
3205 }
3206 x = sk_X509_value(ctx->chain, num-1);
3207
3208 /*
3209 * Once we run out of untrusted issuers, we stop looking for more
3210 * and start looking only in the trust store if enabled.
3211 */
3212 xtmp = (ss || depth < num) ? NULL : find_issuer(ctx, sktmp, x);
3213 if (xtmp == NULL) {
3214 search &= ~S_DOUNTRUSTED;
3215 if (may_trusted)
3216 search |= S_DOTRUSTED;
3217 continue;
3218 }
3219
3220 /* Drop this issuer from future consideration */
3221 (void) sk_X509_delete_ptr(sktmp, xtmp);
3222
3223 if (!X509_up_ref(xtmp)) {
3224 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
3225 trust = X509_TRUST_REJECTED;
3226 ctx->error = X509_V_ERR_UNSPECIFIED;
3227 search = 0;
3228 continue;
3229 }
3230
3231 if (!sk_X509_push(ctx->chain, xtmp)) {
3232 X509_free(xtmp);
3233 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
3234 trust = X509_TRUST_REJECTED;
3235 ctx->error = X509_V_ERR_OUT_OF_MEM;
3236 search = 0;
3237 continue;
3238 }
3239
3240 x = xtmp;
3241 ++ctx->num_untrusted;
3242 ss = cert_self_signed(xtmp);
3243
3244 /*
3245 * Check for DANE-TA trust of the topmost untrusted certificate.
3246 */
3247 switch (trust = check_dane_issuer(ctx, ctx->num_untrusted - 1)) {
3248 case X509_TRUST_TRUSTED:
3249 case X509_TRUST_REJECTED:
3250 search = 0;
3251 continue;
3252 }
3253 }
3254 }
3255 sk_X509_free(sktmp);
3256
3257 /*
3258 * Last chance to make a trusted chain, either bare DANE-TA public-key
3259 * signers, or else direct leaf PKIX trust.
3260 */
3261 num = sk_X509_num(ctx->chain);
3262 if (num <= depth) {
3263 if (trust == X509_TRUST_UNTRUSTED && DANETLS_HAS_DANE_TA(dane))
3264 trust = check_dane_pkeys(ctx);
3265 if (trust == X509_TRUST_UNTRUSTED && num == ctx->num_untrusted)
3266 trust = check_trust(ctx, num);
3267 }
3268
3269 switch (trust) {
3270 case X509_TRUST_TRUSTED:
3271 return 1;
3272 case X509_TRUST_REJECTED:
3273 /* Callback already issued */
3274 return 0;
3275 case X509_TRUST_UNTRUSTED:
3276 default:
3277 num = sk_X509_num(ctx->chain);
3278 if (num > depth)
3279 return verify_cb_cert(ctx, NULL, num-1,
3280 X509_V_ERR_CERT_CHAIN_TOO_LONG);
3281 if (DANETLS_ENABLED(dane) &&
3282 (!DANETLS_HAS_PKIX(dane) || dane->pdpth >= 0))
3283 return verify_cb_cert(ctx, NULL, num-1, X509_V_ERR_DANE_NO_MATCH);
3284 if (ss && sk_X509_num(ctx->chain) == 1)
3285 return verify_cb_cert(ctx, NULL, num-1,
3286 X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT);
3287 if (ss)
3288 return verify_cb_cert(ctx, NULL, num-1,
3289 X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN);
3290 if (ctx->num_untrusted < num)
3291 return verify_cb_cert(ctx, NULL, num-1,
3292 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT);
3293 return verify_cb_cert(ctx, NULL, num-1,
3294 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY);
3295 }
3296}
3297
3298static const int minbits_table[] = { 80, 112, 128, 192, 256 };
3299static const int NUM_AUTH_LEVELS = OSSL_NELEM(minbits_table);
3300
3301/*
3302 * Check whether the public key of ``cert`` meets the security level of
3303 * ``ctx``.
3304 *
3305 * Returns 1 on success, 0 otherwise.
3306 */
3307static int check_key_level(X509_STORE_CTX *ctx, X509 *cert)
3308{
3309 EVP_PKEY *pkey = X509_get0_pubkey(cert);
3310 int level = ctx->param->auth_level;
3311
3312 /*
3313 * At security level zero, return without checking for a supported public
3314 * key type. Some engines support key types not understood outside the
3315 * engine, and we only need to understand the key when enforcing a security
3316 * floor.
3317 */
3318 if (level <= 0)
3319 return 1;
3320
3321 /* Unsupported or malformed keys are not secure */
3322 if (pkey == NULL)
3323 return 0;
3324
3325 if (level > NUM_AUTH_LEVELS)
3326 level = NUM_AUTH_LEVELS;
3327
3328 return EVP_PKEY_security_bits(pkey) >= minbits_table[level - 1];
3329}
3330
3331/*
3332 * Check whether the public key of ``cert`` does not use explicit params
3333 * for an elliptic curve.
3334 *
3335 * Returns 1 on success, 0 if check fails, -1 for other errors.
3336 */
3337static int check_curve(X509 *cert)
3338{
3339#ifndef OPENSSL_NO_EC
3340 EVP_PKEY *pkey = X509_get0_pubkey(cert);
3341
3342 /* Unsupported or malformed key */
3343 if (pkey == NULL)
3344 return -1;
3345
3346 if (EVP_PKEY_id(pkey) == EVP_PKEY_EC) {
3347 int ret;
3348
3349 ret = EC_KEY_decoded_from_explicit_params(EVP_PKEY_get0_EC_KEY(pkey));
3350 return ret < 0 ? ret : !ret;
3351 }
3352#endif
3353
3354 return 1;
3355}
3356
3357/*
3358 * Check whether the signature digest algorithm of ``cert`` meets the security
3359 * level of ``ctx``. Should not be checked for trust anchors (whether
3360 * self-signed or otherwise).
3361 *
3362 * Returns 1 on success, 0 otherwise.
3363 */
3364static int check_sig_level(X509_STORE_CTX *ctx, X509 *cert)
3365{
3366 int secbits = -1;
3367 int level = ctx->param->auth_level;
3368
3369 if (level <= 0)
3370 return 1;
3371 if (level > NUM_AUTH_LEVELS)
3372 level = NUM_AUTH_LEVELS;
3373
3374 if (!X509_get_signature_info(cert, NULL, NULL, &secbits, NULL))
3375 return 0;
3376
3377 return secbits >= minbits_table[level - 1];
3378}
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