1/*
2 * Copyright 1995-2018 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the Apache License 2.0 (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10#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);
83
84static int get_crl_score(X509_STORE_CTX *ctx, X509 **pissuer,
85 unsigned int *preasons, X509_CRL *crl, X509 *x);
86static int get_crl_delta(X509_STORE_CTX *ctx,
87 X509_CRL **pcrl, X509_CRL **pdcrl, X509 *x);
88static void get_delta_sk(X509_STORE_CTX *ctx, X509_CRL **dcrl,
89 int *pcrl_score, X509_CRL *base,
90 STACK_OF(X509_CRL) *crls);
91static void crl_akid_check(X509_STORE_CTX *ctx, X509_CRL *crl, X509 **pissuer,
92 int *pcrl_score);
93static int crl_crldp_check(X509 *x, X509_CRL *crl, int crl_score,
94 unsigned int *preasons);
95static int check_crl_path(X509_STORE_CTX *ctx, X509 *x);
96static int check_crl_chain(X509_STORE_CTX *ctx,
97 STACK_OF(X509) *cert_path,
98 STACK_OF(X509) *crl_path);
99
100static int internal_verify(X509_STORE_CTX *ctx);
101
102static int null_callback(int ok, X509_STORE_CTX *e)
103{
104 return ok;
105}
106
107/* Return 1 is a certificate is self signed */
108static int cert_self_signed(X509 *x)
109{
110 /*
111 * FIXME: x509v3_cache_extensions() needs to detect more failures and not
112 * set EXFLAG_SET when that happens. Especially, if the failures are
113 * parse errors, rather than memory pressure!
114 */
115 X509_check_purpose(x, -1, 0);
116 if (x->ex_flags & EXFLAG_SS)
117 return 1;
118 else
119 return 0;
120}
121
122/* Given a certificate try and find an exact match in the store */
123
124static X509 *lookup_cert_match(X509_STORE_CTX *ctx, X509 *x)
125{
126 STACK_OF(X509) *certs;
127 X509 *xtmp = NULL;
128 int i;
129 /* Lookup all certs with matching subject name */
130 certs = ctx->lookup_certs(ctx, X509_get_subject_name(x));
131 if (certs == NULL)
132 return NULL;
133 /* Look for exact match */
134 for (i = 0; i < sk_X509_num(certs); i++) {
135 xtmp = sk_X509_value(certs, i);
136 if (!X509_cmp(xtmp, x))
137 break;
138 }
139 if (i < sk_X509_num(certs))
140 X509_up_ref(xtmp);
141 else
142 xtmp = NULL;
143 sk_X509_pop_free(certs, X509_free);
144 return xtmp;
145}
146
147/*-
148 * Inform the verify callback of an error.
149 * If B<x> is not NULL it is the error cert, otherwise use the chain cert at
150 * B<depth>.
151 * If B<err> is not X509_V_OK, that's the error value, otherwise leave
152 * unchanged (presumably set by the caller).
153 *
154 * Returns 0 to abort verification with an error, non-zero to continue.
155 */
156static int verify_cb_cert(X509_STORE_CTX *ctx, X509 *x, int depth, int err)
157{
158 ctx->error_depth = depth;
159 ctx->current_cert = (x != NULL) ? x : sk_X509_value(ctx->chain, depth);
160 if (err != X509_V_OK)
161 ctx->error = err;
162 return ctx->verify_cb(0, ctx);
163}
164
165/*-
166 * Inform the verify callback of an error, CRL-specific variant. Here, the
167 * error depth and certificate are already set, we just specify the error
168 * number.
169 *
170 * Returns 0 to abort verification with an error, non-zero to continue.
171 */
172static int verify_cb_crl(X509_STORE_CTX *ctx, int err)
173{
174 ctx->error = err;
175 return ctx->verify_cb(0, ctx);
176}
177
178static int check_auth_level(X509_STORE_CTX *ctx)
179{
180 int i;
181 int num = sk_X509_num(ctx->chain);
182
183 if (ctx->param->auth_level <= 0)
184 return 1;
185
186 for (i = 0; i < num; ++i) {
187 X509 *cert = sk_X509_value(ctx->chain, i);
188
189 /*
190 * We've already checked the security of the leaf key, so here we only
191 * check the security of issuer keys.
192 */
193 if (i > 0 && !check_key_level(ctx, cert) &&
194 verify_cb_cert(ctx, cert, i, X509_V_ERR_CA_KEY_TOO_SMALL) == 0)
195 return 0;
196 /*
197 * We also check the signature algorithm security of all certificates
198 * except those of the trust anchor at index num-1.
199 */
200 if (i < num - 1 && !check_sig_level(ctx, cert) &&
201 verify_cb_cert(ctx, cert, i, X509_V_ERR_CA_MD_TOO_WEAK) == 0)
202 return 0;
203 }
204 return 1;
205}
206
207static int verify_chain(X509_STORE_CTX *ctx)
208{
209 int err;
210 int ok;
211
212 /*
213 * Before either returning with an error, or continuing with CRL checks,
214 * instantiate chain public key parameters.
215 */
216 if ((ok = build_chain(ctx)) == 0 ||
217 (ok = check_chain_extensions(ctx)) == 0 ||
218 (ok = check_auth_level(ctx)) == 0 ||
219 (ok = check_id(ctx)) == 0 || 1)
220 X509_get_pubkey_parameters(NULL, ctx->chain);
221 if (ok == 0 || (ok = ctx->check_revocation(ctx)) == 0)
222 return ok;
223
224 err = X509_chain_check_suiteb(&ctx->error_depth, NULL, ctx->chain,
225 ctx->param->flags);
226 if (err != X509_V_OK) {
227 if ((ok = verify_cb_cert(ctx, NULL, ctx->error_depth, err)) == 0)
228 return ok;
229 }
230
231 /* Verify chain signatures and expiration times */
232 ok = (ctx->verify != NULL) ? ctx->verify(ctx) : internal_verify(ctx);
233 if (!ok)
234 return ok;
235
236 if ((ok = check_name_constraints(ctx)) == 0)
237 return ok;
238
239#ifndef OPENSSL_NO_RFC3779
240 /* RFC 3779 path validation, now that CRL check has been done */
241 if ((ok = X509v3_asid_validate_path(ctx)) == 0)
242 return ok;
243 if ((ok = X509v3_addr_validate_path(ctx)) == 0)
244 return ok;
245#endif
246
247 /* If we get this far evaluate policies */
248 if (ctx->param->flags & X509_V_FLAG_POLICY_CHECK)
249 ok = ctx->check_policy(ctx);
250 return ok;
251}
252
253int X509_verify_cert(X509_STORE_CTX *ctx)
254{
255 SSL_DANE *dane = ctx->dane;
256 int ret;
257
258 if (ctx->cert == NULL) {
259 X509err(X509_F_X509_VERIFY_CERT, X509_R_NO_CERT_SET_FOR_US_TO_VERIFY);
260 ctx->error = X509_V_ERR_INVALID_CALL;
261 return -1;
262 }
263
264 if (ctx->chain != NULL) {
265 /*
266 * This X509_STORE_CTX has already been used to verify a cert. We
267 * cannot do another one.
268 */
269 X509err(X509_F_X509_VERIFY_CERT, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
270 ctx->error = X509_V_ERR_INVALID_CALL;
271 return -1;
272 }
273
274 /*
275 * first we make sure the chain we are going to build is present and that
276 * the first entry is in place
277 */
278 if (((ctx->chain = sk_X509_new_null()) == NULL) ||
279 (!sk_X509_push(ctx->chain, ctx->cert))) {
280 X509err(X509_F_X509_VERIFY_CERT, ERR_R_MALLOC_FAILURE);
281 ctx->error = X509_V_ERR_OUT_OF_MEM;
282 return -1;
283 }
284 X509_up_ref(ctx->cert);
285 ctx->num_untrusted = 1;
286
287 /* If the peer's public key is too weak, we can stop early. */
288 if (!check_key_level(ctx, ctx->cert) &&
289 !verify_cb_cert(ctx, ctx->cert, 0, X509_V_ERR_EE_KEY_TOO_SMALL))
290 return 0;
291
292 if (DANETLS_ENABLED(dane))
293 ret = dane_verify(ctx);
294 else
295 ret = verify_chain(ctx);
296
297 /*
298 * Safety-net. If we are returning an error, we must also set ctx->error,
299 * so that the chain is not considered verified should the error be ignored
300 * (e.g. TLS with SSL_VERIFY_NONE).
301 */
302 if (ret <= 0 && ctx->error == X509_V_OK)
303 ctx->error = X509_V_ERR_UNSPECIFIED;
304 return ret;
305}
306
307/*
308 * Given a STACK_OF(X509) find the issuer of cert (if any)
309 */
310static X509 *find_issuer(X509_STORE_CTX *ctx, STACK_OF(X509) *sk, X509 *x)
311{
312 int i;
313 X509 *issuer, *rv = NULL;
314
315 for (i = 0; i < sk_X509_num(sk); i++) {
316 issuer = sk_X509_value(sk, i);
317 if (ctx->check_issued(ctx, x, issuer)) {
318 rv = issuer;
319 if (x509_check_cert_time(ctx, rv, -1))
320 break;
321 }
322 }
323 return rv;
324}
325
326/* Given a possible certificate and issuer check them */
327
328static int check_issued(X509_STORE_CTX *ctx, X509 *x, X509 *issuer)
329{
330 int ret;
331 if (x == issuer)
332 return cert_self_signed(x);
333 ret = X509_check_issued(issuer, x);
334 if (ret == X509_V_OK) {
335 int i;
336 X509 *ch;
337 /* Special case: single self signed certificate */
338 if (cert_self_signed(x) && sk_X509_num(ctx->chain) == 1)
339 return 1;
340 for (i = 0; i < sk_X509_num(ctx->chain); i++) {
341 ch = sk_X509_value(ctx->chain, i);
342 if (ch == issuer || !X509_cmp(ch, issuer)) {
343 ret = X509_V_ERR_PATH_LOOP;
344 break;
345 }
346 }
347 }
348
349 return (ret == X509_V_OK);
350}
351
352/* Alternative lookup method: look from a STACK stored in other_ctx */
353
354static int get_issuer_sk(X509 **issuer, X509_STORE_CTX *ctx, X509 *x)
355{
356 *issuer = find_issuer(ctx, ctx->other_ctx, x);
357 if (*issuer) {
358 X509_up_ref(*issuer);
359 return 1;
360 } else
361 return 0;
362}
363
364static STACK_OF(X509) *lookup_certs_sk(X509_STORE_CTX *ctx, X509_NAME *nm)
365{
366 STACK_OF(X509) *sk = NULL;
367 X509 *x;
368 int i;
369
370 for (i = 0; i < sk_X509_num(ctx->other_ctx); i++) {
371 x = sk_X509_value(ctx->other_ctx, i);
372 if (X509_NAME_cmp(nm, X509_get_subject_name(x)) == 0) {
373 if (sk == NULL)
374 sk = sk_X509_new_null();
375 if (sk == NULL || sk_X509_push(sk, x) == 0) {
376 sk_X509_pop_free(sk, X509_free);
377 X509err(X509_F_LOOKUP_CERTS_SK, ERR_R_MALLOC_FAILURE);
378 ctx->error = X509_V_ERR_OUT_OF_MEM;
379 return NULL;
380 }
381 X509_up_ref(x);
382 }
383 }
384 return sk;
385}
386
387/*
388 * Check EE or CA certificate purpose. For trusted certificates explicit local
389 * auxiliary trust can be used to override EKU-restrictions.
390 */
391static int check_purpose(X509_STORE_CTX *ctx, X509 *x, int purpose, int depth,
392 int must_be_ca)
393{
394 int tr_ok = X509_TRUST_UNTRUSTED;
395
396 /*
397 * For trusted certificates we want to see whether any auxiliary trust
398 * settings trump the purpose constraints.
399 *
400 * This is complicated by the fact that the trust ordinals in
401 * ctx->param->trust are entirely independent of the purpose ordinals in
402 * ctx->param->purpose!
403 *
404 * What connects them is their mutual initialization via calls from
405 * X509_STORE_CTX_set_default() into X509_VERIFY_PARAM_lookup() which sets
406 * related values of both param->trust and param->purpose. It is however
407 * typically possible to infer associated trust values from a purpose value
408 * via the X509_PURPOSE API.
409 *
410 * Therefore, we can only check for trust overrides when the purpose we're
411 * checking is the same as ctx->param->purpose and ctx->param->trust is
412 * also set.
413 */
414 if (depth >= ctx->num_untrusted && purpose == ctx->param->purpose)
415 tr_ok = X509_check_trust(x, ctx->param->trust, X509_TRUST_NO_SS_COMPAT);
416
417 switch (tr_ok) {
418 case X509_TRUST_TRUSTED:
419 return 1;
420 case X509_TRUST_REJECTED:
421 break;
422 default:
423 switch (X509_check_purpose(x, purpose, must_be_ca > 0)) {
424 case 1:
425 return 1;
426 case 0:
427 break;
428 default:
429 if ((ctx->param->flags & X509_V_FLAG_X509_STRICT) == 0)
430 return 1;
431 }
432 break;
433 }
434
435 return verify_cb_cert(ctx, x, depth, X509_V_ERR_INVALID_PURPOSE);
436}
437
438/*
439 * Check a certificate chains extensions for consistency with the supplied
440 * purpose
441 */
442
443static int check_chain_extensions(X509_STORE_CTX *ctx)
444{
445 int i, must_be_ca, plen = 0;
446 X509 *x;
447 int proxy_path_length = 0;
448 int purpose;
449 int allow_proxy_certs;
450 int num = sk_X509_num(ctx->chain);
451
452 /*-
453 * must_be_ca can have 1 of 3 values:
454 * -1: we accept both CA and non-CA certificates, to allow direct
455 * use of self-signed certificates (which are marked as CA).
456 * 0: we only accept non-CA certificates. This is currently not
457 * used, but the possibility is present for future extensions.
458 * 1: we only accept CA certificates. This is currently used for
459 * all certificates in the chain except the leaf certificate.
460 */
461 must_be_ca = -1;
462
463 /* CRL path validation */
464 if (ctx->parent) {
465 allow_proxy_certs = 0;
466 purpose = X509_PURPOSE_CRL_SIGN;
467 } else {
468 allow_proxy_certs =
469 ! !(ctx->param->flags & X509_V_FLAG_ALLOW_PROXY_CERTS);
470 purpose = ctx->param->purpose;
471 }
472
473 for (i = 0; i < num; i++) {
474 int ret;
475 x = sk_X509_value(ctx->chain, i);
476 if (!(ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL)
477 && (x->ex_flags & EXFLAG_CRITICAL)) {
478 if (!verify_cb_cert(ctx, x, i,
479 X509_V_ERR_UNHANDLED_CRITICAL_EXTENSION))
480 return 0;
481 }
482 if (!allow_proxy_certs && (x->ex_flags & EXFLAG_PROXY)) {
483 if (!verify_cb_cert(ctx, x, i,
484 X509_V_ERR_PROXY_CERTIFICATES_NOT_ALLOWED))
485 return 0;
486 }
487 ret = X509_check_ca(x);
488 switch (must_be_ca) {
489 case -1:
490 if ((ctx->param->flags & X509_V_FLAG_X509_STRICT)
491 && (ret != 1) && (ret != 0)) {
492 ret = 0;
493 ctx->error = X509_V_ERR_INVALID_CA;
494 } else
495 ret = 1;
496 break;
497 case 0:
498 if (ret != 0) {
499 ret = 0;
500 ctx->error = X509_V_ERR_INVALID_NON_CA;
501 } else
502 ret = 1;
503 break;
504 default:
505 /* X509_V_FLAG_X509_STRICT is implicit for intermediate CAs */
506 if ((ret == 0)
507 || ((i + 1 < num || ctx->param->flags & X509_V_FLAG_X509_STRICT)
508 && (ret != 1))) {
509 ret = 0;
510 ctx->error = X509_V_ERR_INVALID_CA;
511 } else
512 ret = 1;
513 break;
514 }
515 if (ret == 0 && !verify_cb_cert(ctx, x, i, X509_V_OK))
516 return 0;
517 /* check_purpose() makes the callback as needed */
518 if (purpose > 0 && !check_purpose(ctx, x, purpose, i, must_be_ca))
519 return 0;
520 /* Check pathlen */
521 if ((i > 1) && (x->ex_pathlen != -1)
522 && (plen > (x->ex_pathlen + proxy_path_length))) {
523 if (!verify_cb_cert(ctx, x, i, X509_V_ERR_PATH_LENGTH_EXCEEDED))
524 return 0;
525 }
526 /* Increment path length if not a self issued intermediate CA */
527 if (i > 0 && (x->ex_flags & EXFLAG_SI) == 0)
528 plen++;
529 /*
530 * If this certificate is a proxy certificate, the next certificate
531 * must be another proxy certificate or a EE certificate. If not,
532 * the next certificate must be a CA certificate.
533 */
534 if (x->ex_flags & EXFLAG_PROXY) {
535 /*
536 * RFC3820, 4.1.3 (b)(1) stipulates that if pCPathLengthConstraint
537 * is less than max_path_length, the former should be copied to
538 * the latter, and 4.1.4 (a) stipulates that max_path_length
539 * should be verified to be larger than zero and decrement it.
540 *
541 * Because we're checking the certs in the reverse order, we start
542 * with verifying that proxy_path_length isn't larger than pcPLC,
543 * and copy the latter to the former if it is, and finally,
544 * increment proxy_path_length.
545 */
546 if (x->ex_pcpathlen != -1) {
547 if (proxy_path_length > x->ex_pcpathlen) {
548 if (!verify_cb_cert(ctx, x, i,
549 X509_V_ERR_PROXY_PATH_LENGTH_EXCEEDED))
550 return 0;
551 }
552 proxy_path_length = x->ex_pcpathlen;
553 }
554 proxy_path_length++;
555 must_be_ca = 0;
556 } else
557 must_be_ca = 1;
558 }
559 return 1;
560}
561
562static int has_san_id(X509 *x, int gtype)
563{
564 int i;
565 int ret = 0;
566 GENERAL_NAMES *gs = X509_get_ext_d2i(x, NID_subject_alt_name, NULL, NULL);
567
568 if (gs == NULL)
569 return 0;
570
571 for (i = 0; i < sk_GENERAL_NAME_num(gs); i++) {
572 GENERAL_NAME *g = sk_GENERAL_NAME_value(gs, i);
573
574 if (g->type == gtype) {
575 ret = 1;
576 break;
577 }
578 }
579 GENERAL_NAMES_free(gs);
580 return ret;
581}
582
583static int check_name_constraints(X509_STORE_CTX *ctx)
584{
585 int i;
586
587 /* Check name constraints for all certificates */
588 for (i = sk_X509_num(ctx->chain) - 1; i >= 0; i--) {
589 X509 *x = sk_X509_value(ctx->chain, i);
590 int j;
591
592 /* Ignore self issued certs unless last in chain */
593 if (i && (x->ex_flags & EXFLAG_SI))
594 continue;
595
596 /*
597 * Proxy certificates policy has an extra constraint, where the
598 * certificate subject MUST be the issuer with a single CN entry
599 * added.
600 * (RFC 3820: 3.4, 4.1.3 (a)(4))
601 */
602 if (x->ex_flags & EXFLAG_PROXY) {
603 X509_NAME *tmpsubject = X509_get_subject_name(x);
604 X509_NAME *tmpissuer = X509_get_issuer_name(x);
605 X509_NAME_ENTRY *tmpentry = NULL;
606 int last_object_nid = 0;
607 int err = X509_V_OK;
608 int last_object_loc = X509_NAME_entry_count(tmpsubject) - 1;
609
610 /* Check that there are at least two RDNs */
611 if (last_object_loc < 1) {
612 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
613 goto proxy_name_done;
614 }
615
616 /*
617 * Check that there is exactly one more RDN in subject as
618 * there is in issuer.
619 */
620 if (X509_NAME_entry_count(tmpsubject)
621 != X509_NAME_entry_count(tmpissuer) + 1) {
622 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
623 goto proxy_name_done;
624 }
625
626 /*
627 * Check that the last subject component isn't part of a
628 * multivalued RDN
629 */
630 if (X509_NAME_ENTRY_set(X509_NAME_get_entry(tmpsubject,
631 last_object_loc))
632 == X509_NAME_ENTRY_set(X509_NAME_get_entry(tmpsubject,
633 last_object_loc - 1))) {
634 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
635 goto proxy_name_done;
636 }
637
638 /*
639 * Check that the last subject RDN is a commonName, and that
640 * all the previous RDNs match the issuer exactly
641 */
642 tmpsubject = X509_NAME_dup(tmpsubject);
643 if (tmpsubject == NULL) {
644 X509err(X509_F_CHECK_NAME_CONSTRAINTS, ERR_R_MALLOC_FAILURE);
645 ctx->error = X509_V_ERR_OUT_OF_MEM;
646 return 0;
647 }
648
649 tmpentry =
650 X509_NAME_delete_entry(tmpsubject, last_object_loc);
651 last_object_nid =
652 OBJ_obj2nid(X509_NAME_ENTRY_get_object(tmpentry));
653
654 if (last_object_nid != NID_commonName
655 || X509_NAME_cmp(tmpsubject, tmpissuer) != 0) {
656 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
657 }
658
659 X509_NAME_ENTRY_free(tmpentry);
660 X509_NAME_free(tmpsubject);
661
662 proxy_name_done:
663 if (err != X509_V_OK
664 && !verify_cb_cert(ctx, x, i, err))
665 return 0;
666 }
667
668 /*
669 * Check against constraints for all certificates higher in chain
670 * including trust anchor. Trust anchor not strictly speaking needed
671 * but if it includes constraints it is to be assumed it expects them
672 * to be obeyed.
673 */
674 for (j = sk_X509_num(ctx->chain) - 1; j > i; j--) {
675 NAME_CONSTRAINTS *nc = sk_X509_value(ctx->chain, j)->nc;
676
677 if (nc) {
678 int rv = NAME_CONSTRAINTS_check(x, nc);
679
680 /* If EE certificate check commonName too */
681 if (rv == X509_V_OK && i == 0
682 && (ctx->param->hostflags
683 & X509_CHECK_FLAG_NEVER_CHECK_SUBJECT) == 0
684 && ((ctx->param->hostflags
685 & X509_CHECK_FLAG_ALWAYS_CHECK_SUBJECT) != 0
686 || !has_san_id(x, GEN_DNS)))
687 rv = NAME_CONSTRAINTS_check_CN(x, nc);
688
689 switch (rv) {
690 case X509_V_OK:
691 break;
692 case X509_V_ERR_OUT_OF_MEM:
693 return 0;
694 default:
695 if (!verify_cb_cert(ctx, x, i, rv))
696 return 0;
697 break;
698 }
699 }
700 }
701 }
702 return 1;
703}
704
705static int check_id_error(X509_STORE_CTX *ctx, int errcode)
706{
707 return verify_cb_cert(ctx, ctx->cert, 0, errcode);
708}
709
710static int check_hosts(X509 *x, X509_VERIFY_PARAM *vpm)
711{
712 int i;
713 int n = sk_OPENSSL_STRING_num(vpm->hosts);
714 char *name;
715
716 if (vpm->peername != NULL) {
717 OPENSSL_free(vpm->peername);
718 vpm->peername = NULL;
719 }
720 for (i = 0; i < n; ++i) {
721 name = sk_OPENSSL_STRING_value(vpm->hosts, i);
722 if (X509_check_host(x, name, 0, vpm->hostflags, &vpm->peername) > 0)
723 return 1;
724 }
725 return n == 0;
726}
727
728static int check_id(X509_STORE_CTX *ctx)
729{
730 X509_VERIFY_PARAM *vpm = ctx->param;
731 X509 *x = ctx->cert;
732 if (vpm->hosts && check_hosts(x, vpm) <= 0) {
733 if (!check_id_error(ctx, X509_V_ERR_HOSTNAME_MISMATCH))
734 return 0;
735 }
736 if (vpm->email && X509_check_email(x, vpm->email, vpm->emaillen, 0) <= 0) {
737 if (!check_id_error(ctx, X509_V_ERR_EMAIL_MISMATCH))
738 return 0;
739 }
740 if (vpm->ip && X509_check_ip(x, vpm->ip, vpm->iplen, 0) <= 0) {
741 if (!check_id_error(ctx, X509_V_ERR_IP_ADDRESS_MISMATCH))
742 return 0;
743 }
744 return 1;
745}
746
747static int check_trust(X509_STORE_CTX *ctx, int num_untrusted)
748{
749 int i;
750 X509 *x = NULL;
751 X509 *mx;
752 SSL_DANE *dane = ctx->dane;
753 int num = sk_X509_num(ctx->chain);
754 int trust;
755
756 /*
757 * Check for a DANE issuer at depth 1 or greater, if it is a DANE-TA(2)
758 * match, we're done, otherwise we'll merely record the match depth.
759 */
760 if (DANETLS_HAS_TA(dane) && num_untrusted > 0 && num_untrusted < num) {
761 switch (trust = check_dane_issuer(ctx, num_untrusted)) {
762 case X509_TRUST_TRUSTED:
763 case X509_TRUST_REJECTED:
764 return trust;
765 }
766 }
767
768 /*
769 * Check trusted certificates in chain at depth num_untrusted and up.
770 * Note, that depths 0..num_untrusted-1 may also contain trusted
771 * certificates, but the caller is expected to have already checked those,
772 * and wants to incrementally check just any added since.
773 */
774 for (i = num_untrusted; i < num; i++) {
775 x = sk_X509_value(ctx->chain, i);
776 trust = X509_check_trust(x, ctx->param->trust, 0);
777 /* If explicitly trusted return trusted */
778 if (trust == X509_TRUST_TRUSTED)
779 goto trusted;
780 if (trust == X509_TRUST_REJECTED)
781 goto rejected;
782 }
783
784 /*
785 * If we are looking at a trusted certificate, and accept partial chains,
786 * the chain is PKIX trusted.
787 */
788 if (num_untrusted < num) {
789 if (ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN)
790 goto trusted;
791 return X509_TRUST_UNTRUSTED;
792 }
793
794 if (num_untrusted == num && ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) {
795 /*
796 * Last-resort call with no new trusted certificates, check the leaf
797 * for a direct trust store match.
798 */
799 i = 0;
800 x = sk_X509_value(ctx->chain, i);
801 mx = lookup_cert_match(ctx, x);
802 if (!mx)
803 return X509_TRUST_UNTRUSTED;
804
805 /*
806 * Check explicit auxiliary trust/reject settings. If none are set,
807 * we'll accept X509_TRUST_UNTRUSTED when not self-signed.
808 */
809 trust = X509_check_trust(mx, ctx->param->trust, 0);
810 if (trust == X509_TRUST_REJECTED) {
811 X509_free(mx);
812 goto rejected;
813 }
814
815 /* Replace leaf with trusted match */
816 (void) sk_X509_set(ctx->chain, 0, mx);
817 X509_free(x);
818 ctx->num_untrusted = 0;
819 goto trusted;
820 }
821
822 /*
823 * If no trusted certs in chain at all return untrusted and allow
824 * standard (no issuer cert) etc errors to be indicated.
825 */
826 return X509_TRUST_UNTRUSTED;
827
828 rejected:
829 if (!verify_cb_cert(ctx, x, i, X509_V_ERR_CERT_REJECTED))
830 return X509_TRUST_REJECTED;
831 return X509_TRUST_UNTRUSTED;
832
833 trusted:
834 if (!DANETLS_ENABLED(dane))
835 return X509_TRUST_TRUSTED;
836 if (dane->pdpth < 0)
837 dane->pdpth = num_untrusted;
838 /* With DANE, PKIX alone is not trusted until we have both */
839 if (dane->mdpth >= 0)
840 return X509_TRUST_TRUSTED;
841 return X509_TRUST_UNTRUSTED;
842}
843
844static int check_revocation(X509_STORE_CTX *ctx)
845{
846 int i = 0, last = 0, ok = 0;
847 if (!(ctx->param->flags & X509_V_FLAG_CRL_CHECK))
848 return 1;
849 if (ctx->param->flags & X509_V_FLAG_CRL_CHECK_ALL)
850 last = sk_X509_num(ctx->chain) - 1;
851 else {
852 /* If checking CRL paths this isn't the EE certificate */
853 if (ctx->parent)
854 return 1;
855 last = 0;
856 }
857 for (i = 0; i <= last; i++) {
858 ctx->error_depth = i;
859 ok = check_cert(ctx);
860 if (!ok)
861 return ok;
862 }
863 return 1;
864}
865
866static int check_cert(X509_STORE_CTX *ctx)
867{
868 X509_CRL *crl = NULL, *dcrl = NULL;
869 int ok = 0;
870 int cnum = ctx->error_depth;
871 X509 *x = sk_X509_value(ctx->chain, cnum);
872
873 ctx->current_cert = x;
874 ctx->current_issuer = NULL;
875 ctx->current_crl_score = 0;
876 ctx->current_reasons = 0;
877
878 if (x->ex_flags & EXFLAG_PROXY)
879 return 1;
880
881 while (ctx->current_reasons != CRLDP_ALL_REASONS) {
882 unsigned int last_reasons = ctx->current_reasons;
883
884 /* Try to retrieve relevant CRL */
885 if (ctx->get_crl)
886 ok = ctx->get_crl(ctx, &crl, x);
887 else
888 ok = get_crl_delta(ctx, &crl, &dcrl, x);
889 /*
890 * If error looking up CRL, nothing we can do except notify callback
891 */
892 if (!ok) {
893 ok = verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL);
894 goto done;
895 }
896 ctx->current_crl = crl;
897 ok = ctx->check_crl(ctx, crl);
898 if (!ok)
899 goto done;
900
901 if (dcrl) {
902 ok = ctx->check_crl(ctx, dcrl);
903 if (!ok)
904 goto done;
905 ok = ctx->cert_crl(ctx, dcrl, x);
906 if (!ok)
907 goto done;
908 } else
909 ok = 1;
910
911 /* Don't look in full CRL if delta reason is removefromCRL */
912 if (ok != 2) {
913 ok = ctx->cert_crl(ctx, crl, x);
914 if (!ok)
915 goto done;
916 }
917
918 X509_CRL_free(crl);
919 X509_CRL_free(dcrl);
920 crl = NULL;
921 dcrl = NULL;
922 /*
923 * If reasons not updated we won't get anywhere by another iteration,
924 * so exit loop.
925 */
926 if (last_reasons == ctx->current_reasons) {
927 ok = verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL);
928 goto done;
929 }
930 }
931 done:
932 X509_CRL_free(crl);
933 X509_CRL_free(dcrl);
934
935 ctx->current_crl = NULL;
936 return ok;
937}
938
939/* Check CRL times against values in X509_STORE_CTX */
940
941static int check_crl_time(X509_STORE_CTX *ctx, X509_CRL *crl, int notify)
942{
943 time_t *ptime;
944 int i;
945
946 if (notify)
947 ctx->current_crl = crl;
948 if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME)
949 ptime = &ctx->param->check_time;
950 else if (ctx->param->flags & X509_V_FLAG_NO_CHECK_TIME)
951 return 1;
952 else
953 ptime = NULL;
954
955 i = X509_cmp_time(X509_CRL_get0_lastUpdate(crl), ptime);
956 if (i == 0) {
957 if (!notify)
958 return 0;
959 if (!verify_cb_crl(ctx, X509_V_ERR_ERROR_IN_CRL_LAST_UPDATE_FIELD))
960 return 0;
961 }
962
963 if (i > 0) {
964 if (!notify)
965 return 0;
966 if (!verify_cb_crl(ctx, X509_V_ERR_CRL_NOT_YET_VALID))
967 return 0;
968 }
969
970 if (X509_CRL_get0_nextUpdate(crl)) {
971 i = X509_cmp_time(X509_CRL_get0_nextUpdate(crl), ptime);
972
973 if (i == 0) {
974 if (!notify)
975 return 0;
976 if (!verify_cb_crl(ctx, X509_V_ERR_ERROR_IN_CRL_NEXT_UPDATE_FIELD))
977 return 0;
978 }
979 /* Ignore expiry of base CRL is delta is valid */
980 if ((i < 0) && !(ctx->current_crl_score & CRL_SCORE_TIME_DELTA)) {
981 if (!notify)
982 return 0;
983 if (!verify_cb_crl(ctx, X509_V_ERR_CRL_HAS_EXPIRED))
984 return 0;
985 }
986 }
987
988 if (notify)
989 ctx->current_crl = NULL;
990
991 return 1;
992}
993
994static int get_crl_sk(X509_STORE_CTX *ctx, X509_CRL **pcrl, X509_CRL **pdcrl,
995 X509 **pissuer, int *pscore, unsigned int *preasons,
996 STACK_OF(X509_CRL) *crls)
997{
998 int i, crl_score, best_score = *pscore;
999 unsigned int reasons, best_reasons = 0;
1000 X509 *x = ctx->current_cert;
1001 X509_CRL *crl, *best_crl = NULL;
1002 X509 *crl_issuer = NULL, *best_crl_issuer = NULL;
1003
1004 for (i = 0; i < sk_X509_CRL_num(crls); i++) {
1005 crl = sk_X509_CRL_value(crls, i);
1006 reasons = *preasons;
1007 crl_score = get_crl_score(ctx, &crl_issuer, &reasons, crl, x);
1008 if (crl_score < best_score || crl_score == 0)
1009 continue;
1010 /* If current CRL is equivalent use it if it is newer */
1011 if (crl_score == best_score && best_crl != NULL) {
1012 int day, sec;
1013 if (ASN1_TIME_diff(&day, &sec, X509_CRL_get0_lastUpdate(best_crl),
1014 X509_CRL_get0_lastUpdate(crl)) == 0)
1015 continue;
1016 /*
1017 * ASN1_TIME_diff never returns inconsistent signs for |day|
1018 * and |sec|.
1019 */
1020 if (day <= 0 && sec <= 0)
1021 continue;
1022 }
1023 best_crl = crl;
1024 best_crl_issuer = crl_issuer;
1025 best_score = crl_score;
1026 best_reasons = reasons;
1027 }
1028
1029 if (best_crl) {
1030 X509_CRL_free(*pcrl);
1031 *pcrl = best_crl;
1032 *pissuer = best_crl_issuer;
1033 *pscore = best_score;
1034 *preasons = best_reasons;
1035 X509_CRL_up_ref(best_crl);
1036 X509_CRL_free(*pdcrl);
1037 *pdcrl = NULL;
1038 get_delta_sk(ctx, pdcrl, pscore, best_crl, crls);
1039 }
1040
1041 if (best_score >= CRL_SCORE_VALID)
1042 return 1;
1043
1044 return 0;
1045}
1046
1047/*
1048 * Compare two CRL extensions for delta checking purposes. They should be
1049 * both present or both absent. If both present all fields must be identical.
1050 */
1051
1052static int crl_extension_match(X509_CRL *a, X509_CRL *b, int nid)
1053{
1054 ASN1_OCTET_STRING *exta, *extb;
1055 int i;
1056 i = X509_CRL_get_ext_by_NID(a, nid, -1);
1057 if (i >= 0) {
1058 /* Can't have multiple occurrences */
1059 if (X509_CRL_get_ext_by_NID(a, nid, i) != -1)
1060 return 0;
1061 exta = X509_EXTENSION_get_data(X509_CRL_get_ext(a, i));
1062 } else
1063 exta = NULL;
1064
1065 i = X509_CRL_get_ext_by_NID(b, nid, -1);
1066
1067 if (i >= 0) {
1068
1069 if (X509_CRL_get_ext_by_NID(b, nid, i) != -1)
1070 return 0;
1071 extb = X509_EXTENSION_get_data(X509_CRL_get_ext(b, i));
1072 } else
1073 extb = NULL;
1074
1075 if (!exta && !extb)
1076 return 1;
1077
1078 if (!exta || !extb)
1079 return 0;
1080
1081 if (ASN1_OCTET_STRING_cmp(exta, extb))
1082 return 0;
1083
1084 return 1;
1085}
1086
1087/* See if a base and delta are compatible */
1088
1089static int check_delta_base(X509_CRL *delta, X509_CRL *base)
1090{
1091 /* Delta CRL must be a delta */
1092 if (!delta->base_crl_number)
1093 return 0;
1094 /* Base must have a CRL number */
1095 if (!base->crl_number)
1096 return 0;
1097 /* Issuer names must match */
1098 if (X509_NAME_cmp(X509_CRL_get_issuer(base), X509_CRL_get_issuer(delta)))
1099 return 0;
1100 /* AKID and IDP must match */
1101 if (!crl_extension_match(delta, base, NID_authority_key_identifier))
1102 return 0;
1103 if (!crl_extension_match(delta, base, NID_issuing_distribution_point))
1104 return 0;
1105 /* Delta CRL base number must not exceed Full CRL number. */
1106 if (ASN1_INTEGER_cmp(delta->base_crl_number, base->crl_number) > 0)
1107 return 0;
1108 /* Delta CRL number must exceed full CRL number */
1109 if (ASN1_INTEGER_cmp(delta->crl_number, base->crl_number) > 0)
1110 return 1;
1111 return 0;
1112}
1113
1114/*
1115 * For a given base CRL find a delta... maybe extend to delta scoring or
1116 * retrieve a chain of deltas...
1117 */
1118
1119static void get_delta_sk(X509_STORE_CTX *ctx, X509_CRL **dcrl, int *pscore,
1120 X509_CRL *base, STACK_OF(X509_CRL) *crls)
1121{
1122 X509_CRL *delta;
1123 int i;
1124 if (!(ctx->param->flags & X509_V_FLAG_USE_DELTAS))
1125 return;
1126 if (!((ctx->current_cert->ex_flags | base->flags) & EXFLAG_FRESHEST))
1127 return;
1128 for (i = 0; i < sk_X509_CRL_num(crls); i++) {
1129 delta = sk_X509_CRL_value(crls, i);
1130 if (check_delta_base(delta, base)) {
1131 if (check_crl_time(ctx, delta, 0))
1132 *pscore |= CRL_SCORE_TIME_DELTA;
1133 X509_CRL_up_ref(delta);
1134 *dcrl = delta;
1135 return;
1136 }
1137 }
1138 *dcrl = NULL;
1139}
1140
1141/*
1142 * For a given CRL return how suitable it is for the supplied certificate
1143 * 'x'. The return value is a mask of several criteria. If the issuer is not
1144 * the certificate issuer this is returned in *pissuer. The reasons mask is
1145 * also used to determine if the CRL is suitable: if no new reasons the CRL
1146 * is rejected, otherwise reasons is updated.
1147 */
1148
1149static int get_crl_score(X509_STORE_CTX *ctx, X509 **pissuer,
1150 unsigned int *preasons, X509_CRL *crl, X509 *x)
1151{
1152
1153 int crl_score = 0;
1154 unsigned int tmp_reasons = *preasons, crl_reasons;
1155
1156 /* First see if we can reject CRL straight away */
1157
1158 /* Invalid IDP cannot be processed */
1159 if (crl->idp_flags & IDP_INVALID)
1160 return 0;
1161 /* Reason codes or indirect CRLs need extended CRL support */
1162 if (!(ctx->param->flags & X509_V_FLAG_EXTENDED_CRL_SUPPORT)) {
1163 if (crl->idp_flags & (IDP_INDIRECT | IDP_REASONS))
1164 return 0;
1165 } else if (crl->idp_flags & IDP_REASONS) {
1166 /* If no new reasons reject */
1167 if (!(crl->idp_reasons & ~tmp_reasons))
1168 return 0;
1169 }
1170 /* Don't process deltas at this stage */
1171 else if (crl->base_crl_number)
1172 return 0;
1173 /* If issuer name doesn't match certificate need indirect CRL */
1174 if (X509_NAME_cmp(X509_get_issuer_name(x), X509_CRL_get_issuer(crl))) {
1175 if (!(crl->idp_flags & IDP_INDIRECT))
1176 return 0;
1177 } else
1178 crl_score |= CRL_SCORE_ISSUER_NAME;
1179
1180 if (!(crl->flags & EXFLAG_CRITICAL))
1181 crl_score |= CRL_SCORE_NOCRITICAL;
1182
1183 /* Check expiry */
1184 if (check_crl_time(ctx, crl, 0))
1185 crl_score |= CRL_SCORE_TIME;
1186
1187 /* Check authority key ID and locate certificate issuer */
1188 crl_akid_check(ctx, crl, pissuer, &crl_score);
1189
1190 /* If we can't locate certificate issuer at this point forget it */
1191
1192 if (!(crl_score & CRL_SCORE_AKID))
1193 return 0;
1194
1195 /* Check cert for matching CRL distribution points */
1196
1197 if (crl_crldp_check(x, crl, crl_score, &crl_reasons)) {
1198 /* If no new reasons reject */
1199 if (!(crl_reasons & ~tmp_reasons))
1200 return 0;
1201 tmp_reasons |= crl_reasons;
1202 crl_score |= CRL_SCORE_SCOPE;
1203 }
1204
1205 *preasons = tmp_reasons;
1206
1207 return crl_score;
1208
1209}
1210
1211static void crl_akid_check(X509_STORE_CTX *ctx, X509_CRL *crl,
1212 X509 **pissuer, int *pcrl_score)
1213{
1214 X509 *crl_issuer = NULL;
1215 X509_NAME *cnm = X509_CRL_get_issuer(crl);
1216 int cidx = ctx->error_depth;
1217 int i;
1218
1219 if (cidx != sk_X509_num(ctx->chain) - 1)
1220 cidx++;
1221
1222 crl_issuer = sk_X509_value(ctx->chain, cidx);
1223
1224 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1225 if (*pcrl_score & CRL_SCORE_ISSUER_NAME) {
1226 *pcrl_score |= CRL_SCORE_AKID | CRL_SCORE_ISSUER_CERT;
1227 *pissuer = crl_issuer;
1228 return;
1229 }
1230 }
1231
1232 for (cidx++; cidx < sk_X509_num(ctx->chain); cidx++) {
1233 crl_issuer = sk_X509_value(ctx->chain, cidx);
1234 if (X509_NAME_cmp(X509_get_subject_name(crl_issuer), cnm))
1235 continue;
1236 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1237 *pcrl_score |= CRL_SCORE_AKID | CRL_SCORE_SAME_PATH;
1238 *pissuer = crl_issuer;
1239 return;
1240 }
1241 }
1242
1243 /* Anything else needs extended CRL support */
1244
1245 if (!(ctx->param->flags & X509_V_FLAG_EXTENDED_CRL_SUPPORT))
1246 return;
1247
1248 /*
1249 * Otherwise the CRL issuer is not on the path. Look for it in the set of
1250 * untrusted certificates.
1251 */
1252 for (i = 0; i < sk_X509_num(ctx->untrusted); i++) {
1253 crl_issuer = sk_X509_value(ctx->untrusted, i);
1254 if (X509_NAME_cmp(X509_get_subject_name(crl_issuer), cnm))
1255 continue;
1256 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1257 *pissuer = crl_issuer;
1258 *pcrl_score |= CRL_SCORE_AKID;
1259 return;
1260 }
1261 }
1262}
1263
1264/*
1265 * Check the path of a CRL issuer certificate. This creates a new
1266 * X509_STORE_CTX and populates it with most of the parameters from the
1267 * parent. This could be optimised somewhat since a lot of path checking will
1268 * be duplicated by the parent, but this will rarely be used in practice.
1269 */
1270
1271static int check_crl_path(X509_STORE_CTX *ctx, X509 *x)
1272{
1273 X509_STORE_CTX crl_ctx;
1274 int ret;
1275
1276 /* Don't allow recursive CRL path validation */
1277 if (ctx->parent)
1278 return 0;
1279 if (!X509_STORE_CTX_init(&crl_ctx, ctx->store, x, ctx->untrusted))
1280 return -1;
1281
1282 crl_ctx.crls = ctx->crls;
1283 /* Copy verify params across */
1284 X509_STORE_CTX_set0_param(&crl_ctx, ctx->param);
1285
1286 crl_ctx.parent = ctx;
1287 crl_ctx.verify_cb = ctx->verify_cb;
1288
1289 /* Verify CRL issuer */
1290 ret = X509_verify_cert(&crl_ctx);
1291 if (ret <= 0)
1292 goto err;
1293
1294 /* Check chain is acceptable */
1295 ret = check_crl_chain(ctx, ctx->chain, crl_ctx.chain);
1296 err:
1297 X509_STORE_CTX_cleanup(&crl_ctx);
1298 return ret;
1299}
1300
1301/*
1302 * RFC3280 says nothing about the relationship between CRL path and
1303 * certificate path, which could lead to situations where a certificate could
1304 * be revoked or validated by a CA not authorised to do so. RFC5280 is more
1305 * strict and states that the two paths must end in the same trust anchor,
1306 * though some discussions remain... until this is resolved we use the
1307 * RFC5280 version
1308 */
1309
1310static int check_crl_chain(X509_STORE_CTX *ctx,
1311 STACK_OF(X509) *cert_path,
1312 STACK_OF(X509) *crl_path)
1313{
1314 X509 *cert_ta, *crl_ta;
1315 cert_ta = sk_X509_value(cert_path, sk_X509_num(cert_path) - 1);
1316 crl_ta = sk_X509_value(crl_path, sk_X509_num(crl_path) - 1);
1317 if (!X509_cmp(cert_ta, crl_ta))
1318 return 1;
1319 return 0;
1320}
1321
1322/*-
1323 * Check for match between two dist point names: three separate cases.
1324 * 1. Both are relative names and compare X509_NAME types.
1325 * 2. One full, one relative. Compare X509_NAME to GENERAL_NAMES.
1326 * 3. Both are full names and compare two GENERAL_NAMES.
1327 * 4. One is NULL: automatic match.
1328 */
1329
1330static int idp_check_dp(DIST_POINT_NAME *a, DIST_POINT_NAME *b)
1331{
1332 X509_NAME *nm = NULL;
1333 GENERAL_NAMES *gens = NULL;
1334 GENERAL_NAME *gena, *genb;
1335 int i, j;
1336 if (!a || !b)
1337 return 1;
1338 if (a->type == 1) {
1339 if (!a->dpname)
1340 return 0;
1341 /* Case 1: two X509_NAME */
1342 if (b->type == 1) {
1343 if (!b->dpname)
1344 return 0;
1345 if (!X509_NAME_cmp(a->dpname, b->dpname))
1346 return 1;
1347 else
1348 return 0;
1349 }
1350 /* Case 2: set name and GENERAL_NAMES appropriately */
1351 nm = a->dpname;
1352 gens = b->name.fullname;
1353 } else if (b->type == 1) {
1354 if (!b->dpname)
1355 return 0;
1356 /* Case 2: set name and GENERAL_NAMES appropriately */
1357 gens = a->name.fullname;
1358 nm = b->dpname;
1359 }
1360
1361 /* Handle case 2 with one GENERAL_NAMES and one X509_NAME */
1362 if (nm) {
1363 for (i = 0; i < sk_GENERAL_NAME_num(gens); i++) {
1364 gena = sk_GENERAL_NAME_value(gens, i);
1365 if (gena->type != GEN_DIRNAME)
1366 continue;
1367 if (!X509_NAME_cmp(nm, gena->d.directoryName))
1368 return 1;
1369 }
1370 return 0;
1371 }
1372
1373 /* Else case 3: two GENERAL_NAMES */
1374
1375 for (i = 0; i < sk_GENERAL_NAME_num(a->name.fullname); i++) {
1376 gena = sk_GENERAL_NAME_value(a->name.fullname, i);
1377 for (j = 0; j < sk_GENERAL_NAME_num(b->name.fullname); j++) {
1378 genb = sk_GENERAL_NAME_value(b->name.fullname, j);
1379 if (!GENERAL_NAME_cmp(gena, genb))
1380 return 1;
1381 }
1382 }
1383
1384 return 0;
1385
1386}
1387
1388static int crldp_check_crlissuer(DIST_POINT *dp, X509_CRL *crl, int crl_score)
1389{
1390 int i;
1391 X509_NAME *nm = X509_CRL_get_issuer(crl);
1392 /* If no CRLissuer return is successful iff don't need a match */
1393 if (!dp->CRLissuer)
1394 return ! !(crl_score & CRL_SCORE_ISSUER_NAME);
1395 for (i = 0; i < sk_GENERAL_NAME_num(dp->CRLissuer); i++) {
1396 GENERAL_NAME *gen = sk_GENERAL_NAME_value(dp->CRLissuer, i);
1397 if (gen->type != GEN_DIRNAME)
1398 continue;
1399 if (!X509_NAME_cmp(gen->d.directoryName, nm))
1400 return 1;
1401 }
1402 return 0;
1403}
1404
1405/* Check CRLDP and IDP */
1406
1407static int crl_crldp_check(X509 *x, X509_CRL *crl, int crl_score,
1408 unsigned int *preasons)
1409{
1410 int i;
1411 if (crl->idp_flags & IDP_ONLYATTR)
1412 return 0;
1413 if (x->ex_flags & EXFLAG_CA) {
1414 if (crl->idp_flags & IDP_ONLYUSER)
1415 return 0;
1416 } else {
1417 if (crl->idp_flags & IDP_ONLYCA)
1418 return 0;
1419 }
1420 *preasons = crl->idp_reasons;
1421 for (i = 0; i < sk_DIST_POINT_num(x->crldp); i++) {
1422 DIST_POINT *dp = sk_DIST_POINT_value(x->crldp, i);
1423 if (crldp_check_crlissuer(dp, crl, crl_score)) {
1424 if (!crl->idp || idp_check_dp(dp->distpoint, crl->idp->distpoint)) {
1425 *preasons &= dp->dp_reasons;
1426 return 1;
1427 }
1428 }
1429 }
1430 if ((!crl->idp || !crl->idp->distpoint)
1431 && (crl_score & CRL_SCORE_ISSUER_NAME))
1432 return 1;
1433 return 0;
1434}
1435
1436/*
1437 * Retrieve CRL corresponding to current certificate. If deltas enabled try
1438 * to find a delta CRL too
1439 */
1440
1441static int get_crl_delta(X509_STORE_CTX *ctx,
1442 X509_CRL **pcrl, X509_CRL **pdcrl, X509 *x)
1443{
1444 int ok;
1445 X509 *issuer = NULL;
1446 int crl_score = 0;
1447 unsigned int reasons;
1448 X509_CRL *crl = NULL, *dcrl = NULL;
1449 STACK_OF(X509_CRL) *skcrl;
1450 X509_NAME *nm = X509_get_issuer_name(x);
1451
1452 reasons = ctx->current_reasons;
1453 ok = get_crl_sk(ctx, &crl, &dcrl,
1454 &issuer, &crl_score, &reasons, ctx->crls);
1455 if (ok)
1456 goto done;
1457
1458 /* Lookup CRLs from store */
1459
1460 skcrl = ctx->lookup_crls(ctx, nm);
1461
1462 /* If no CRLs found and a near match from get_crl_sk use that */
1463 if (!skcrl && crl)
1464 goto done;
1465
1466 get_crl_sk(ctx, &crl, &dcrl, &issuer, &crl_score, &reasons, skcrl);
1467
1468 sk_X509_CRL_pop_free(skcrl, X509_CRL_free);
1469
1470 done:
1471 /* If we got any kind of CRL use it and return success */
1472 if (crl) {
1473 ctx->current_issuer = issuer;
1474 ctx->current_crl_score = crl_score;
1475 ctx->current_reasons = reasons;
1476 *pcrl = crl;
1477 *pdcrl = dcrl;
1478 return 1;
1479 }
1480 return 0;
1481}
1482
1483/* Check CRL validity */
1484static int check_crl(X509_STORE_CTX *ctx, X509_CRL *crl)
1485{
1486 X509 *issuer = NULL;
1487 EVP_PKEY *ikey = NULL;
1488 int cnum = ctx->error_depth;
1489 int chnum = sk_X509_num(ctx->chain) - 1;
1490
1491 /* if we have an alternative CRL issuer cert use that */
1492 if (ctx->current_issuer)
1493 issuer = ctx->current_issuer;
1494 /*
1495 * Else find CRL issuer: if not last certificate then issuer is next
1496 * certificate in chain.
1497 */
1498 else if (cnum < chnum)
1499 issuer = sk_X509_value(ctx->chain, cnum + 1);
1500 else {
1501 issuer = sk_X509_value(ctx->chain, chnum);
1502 /* If not self signed, can't check signature */
1503 if (!ctx->check_issued(ctx, issuer, issuer) &&
1504 !verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL_ISSUER))
1505 return 0;
1506 }
1507
1508 if (issuer == NULL)
1509 return 1;
1510
1511 /*
1512 * Skip most tests for deltas because they have already been done
1513 */
1514 if (!crl->base_crl_number) {
1515 /* Check for cRLSign bit if keyUsage present */
1516 if ((issuer->ex_flags & EXFLAG_KUSAGE) &&
1517 !(issuer->ex_kusage & KU_CRL_SIGN) &&
1518 !verify_cb_crl(ctx, X509_V_ERR_KEYUSAGE_NO_CRL_SIGN))
1519 return 0;
1520
1521 if (!(ctx->current_crl_score & CRL_SCORE_SCOPE) &&
1522 !verify_cb_crl(ctx, X509_V_ERR_DIFFERENT_CRL_SCOPE))
1523 return 0;
1524
1525 if (!(ctx->current_crl_score & CRL_SCORE_SAME_PATH) &&
1526 check_crl_path(ctx, ctx->current_issuer) <= 0 &&
1527 !verify_cb_crl(ctx, X509_V_ERR_CRL_PATH_VALIDATION_ERROR))
1528 return 0;
1529
1530 if ((crl->idp_flags & IDP_INVALID) &&
1531 !verify_cb_crl(ctx, X509_V_ERR_INVALID_EXTENSION))
1532 return 0;
1533 }
1534
1535 if (!(ctx->current_crl_score & CRL_SCORE_TIME) &&
1536 !check_crl_time(ctx, crl, 1))
1537 return 0;
1538
1539 /* Attempt to get issuer certificate public key */
1540 ikey = X509_get0_pubkey(issuer);
1541
1542 if (!ikey &&
1543 !verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY))
1544 return 0;
1545
1546 if (ikey) {
1547 int rv = X509_CRL_check_suiteb(crl, ikey, ctx->param->flags);
1548
1549 if (rv != X509_V_OK && !verify_cb_crl(ctx, rv))
1550 return 0;
1551 /* Verify CRL signature */
1552 if (X509_CRL_verify(crl, ikey) <= 0 &&
1553 !verify_cb_crl(ctx, X509_V_ERR_CRL_SIGNATURE_FAILURE))
1554 return 0;
1555 }
1556 return 1;
1557}
1558
1559/* Check certificate against CRL */
1560static int cert_crl(X509_STORE_CTX *ctx, X509_CRL *crl, X509 *x)
1561{
1562 X509_REVOKED *rev;
1563
1564 /*
1565 * The rules changed for this... previously if a CRL contained unhandled
1566 * critical extensions it could still be used to indicate a certificate
1567 * was revoked. This has since been changed since critical extensions can
1568 * change the meaning of CRL entries.
1569 */
1570 if (!(ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL)
1571 && (crl->flags & EXFLAG_CRITICAL) &&
1572 !verify_cb_crl(ctx, X509_V_ERR_UNHANDLED_CRITICAL_CRL_EXTENSION))
1573 return 0;
1574 /*
1575 * Look for serial number of certificate in CRL. If found, make sure
1576 * reason is not removeFromCRL.
1577 */
1578 if (X509_CRL_get0_by_cert(crl, &rev, x)) {
1579 if (rev->reason == CRL_REASON_REMOVE_FROM_CRL)
1580 return 2;
1581 if (!verify_cb_crl(ctx, X509_V_ERR_CERT_REVOKED))
1582 return 0;
1583 }
1584
1585 return 1;
1586}
1587
1588static int check_policy(X509_STORE_CTX *ctx)
1589{
1590 int ret;
1591
1592 if (ctx->parent)
1593 return 1;
1594 /*
1595 * With DANE, the trust anchor might be a bare public key, not a
1596 * certificate! In that case our chain does not have the trust anchor
1597 * certificate as a top-most element. This comports well with RFC5280
1598 * chain verification, since there too, the trust anchor is not part of the
1599 * chain to be verified. In particular, X509_policy_check() does not look
1600 * at the TA cert, but assumes that it is present as the top-most chain
1601 * element. We therefore temporarily push a NULL cert onto the chain if it
1602 * was verified via a bare public key, and pop it off right after the
1603 * X509_policy_check() call.
1604 */
1605 if (ctx->bare_ta_signed && !sk_X509_push(ctx->chain, NULL)) {
1606 X509err(X509_F_CHECK_POLICY, ERR_R_MALLOC_FAILURE);
1607 ctx->error = X509_V_ERR_OUT_OF_MEM;
1608 return 0;
1609 }
1610 ret = X509_policy_check(&ctx->tree, &ctx->explicit_policy, ctx->chain,
1611 ctx->param->policies, ctx->param->flags);
1612 if (ctx->bare_ta_signed)
1613 sk_X509_pop(ctx->chain);
1614
1615 if (ret == X509_PCY_TREE_INTERNAL) {
1616 X509err(X509_F_CHECK_POLICY, ERR_R_MALLOC_FAILURE);
1617 ctx->error = X509_V_ERR_OUT_OF_MEM;
1618 return 0;
1619 }
1620 /* Invalid or inconsistent extensions */
1621 if (ret == X509_PCY_TREE_INVALID) {
1622 int i;
1623
1624 /* Locate certificates with bad extensions and notify callback. */
1625 for (i = 1; i < sk_X509_num(ctx->chain); i++) {
1626 X509 *x = sk_X509_value(ctx->chain, i);
1627
1628 if (!(x->ex_flags & EXFLAG_INVALID_POLICY))
1629 continue;
1630 if (!verify_cb_cert(ctx, x, i,
1631 X509_V_ERR_INVALID_POLICY_EXTENSION))
1632 return 0;
1633 }
1634 return 1;
1635 }
1636 if (ret == X509_PCY_TREE_FAILURE) {
1637 ctx->current_cert = NULL;
1638 ctx->error = X509_V_ERR_NO_EXPLICIT_POLICY;
1639 return ctx->verify_cb(0, ctx);
1640 }
1641 if (ret != X509_PCY_TREE_VALID) {
1642 X509err(X509_F_CHECK_POLICY, ERR_R_INTERNAL_ERROR);
1643 return 0;
1644 }
1645
1646 if (ctx->param->flags & X509_V_FLAG_NOTIFY_POLICY) {
1647 ctx->current_cert = NULL;
1648 /*
1649 * Verification errors need to be "sticky", a callback may have allowed
1650 * an SSL handshake to continue despite an error, and we must then
1651 * remain in an error state. Therefore, we MUST NOT clear earlier
1652 * verification errors by setting the error to X509_V_OK.
1653 */
1654 if (!ctx->verify_cb(2, ctx))
1655 return 0;
1656 }
1657
1658 return 1;
1659}
1660
1661/*-
1662 * Check certificate validity times.
1663 * If depth >= 0, invoke verification callbacks on error, otherwise just return
1664 * the validation status.
1665 *
1666 * Return 1 on success, 0 otherwise.
1667 */
1668int x509_check_cert_time(X509_STORE_CTX *ctx, X509 *x, int depth)
1669{
1670 time_t *ptime;
1671 int i;
1672
1673 if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME)
1674 ptime = &ctx->param->check_time;
1675 else if (ctx->param->flags & X509_V_FLAG_NO_CHECK_TIME)
1676 return 1;
1677 else
1678 ptime = NULL;
1679
1680 i = X509_cmp_time(X509_get0_notBefore(x), ptime);
1681 if (i >= 0 && depth < 0)
1682 return 0;
1683 if (i == 0 && !verify_cb_cert(ctx, x, depth,
1684 X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD))
1685 return 0;
1686 if (i > 0 && !verify_cb_cert(ctx, x, depth, X509_V_ERR_CERT_NOT_YET_VALID))
1687 return 0;
1688
1689 i = X509_cmp_time(X509_get0_notAfter(x), ptime);
1690 if (i <= 0 && depth < 0)
1691 return 0;
1692 if (i == 0 && !verify_cb_cert(ctx, x, depth,
1693 X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD))
1694 return 0;
1695 if (i < 0 && !verify_cb_cert(ctx, x, depth, X509_V_ERR_CERT_HAS_EXPIRED))
1696 return 0;
1697 return 1;
1698}
1699
1700static int internal_verify(X509_STORE_CTX *ctx)
1701{
1702 int n = sk_X509_num(ctx->chain) - 1;
1703 X509 *xi = sk_X509_value(ctx->chain, n);
1704 X509 *xs;
1705
1706 /*
1707 * With DANE-verified bare public key TA signatures, it remains only to
1708 * check the timestamps of the top certificate. We report the issuer as
1709 * NULL, since all we have is a bare key.
1710 */
1711 if (ctx->bare_ta_signed) {
1712 xs = xi;
1713 xi = NULL;
1714 goto check_cert;
1715 }
1716
1717 if (ctx->check_issued(ctx, xi, xi))
1718 xs = xi;
1719 else {
1720 if (ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) {
1721 xs = xi;
1722 goto check_cert;
1723 }
1724 if (n <= 0)
1725 return verify_cb_cert(ctx, xi, 0,
1726 X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE);
1727 n--;
1728 ctx->error_depth = n;
1729 xs = sk_X509_value(ctx->chain, n);
1730 }
1731
1732 /*
1733 * Do not clear ctx->error=0, it must be "sticky", only the user's callback
1734 * is allowed to reset errors (at its own peril).
1735 */
1736 while (n >= 0) {
1737 EVP_PKEY *pkey;
1738
1739 /*
1740 * Skip signature check for self signed certificates unless explicitly
1741 * asked for. It doesn't add any security and just wastes time. If
1742 * the issuer's public key is unusable, report the issuer certificate
1743 * and its depth (rather than the depth of the subject).
1744 */
1745 if (xs != xi || (ctx->param->flags & X509_V_FLAG_CHECK_SS_SIGNATURE)) {
1746 if ((pkey = X509_get0_pubkey(xi)) == NULL) {
1747 if (!verify_cb_cert(ctx, xi, xi != xs ? n+1 : n,
1748 X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY))
1749 return 0;
1750 } else if (X509_verify(xs, pkey) <= 0) {
1751 if (!verify_cb_cert(ctx, xs, n,
1752 X509_V_ERR_CERT_SIGNATURE_FAILURE))
1753 return 0;
1754 }
1755 }
1756
1757 check_cert:
1758 /* Calls verify callback as needed */
1759 if (!x509_check_cert_time(ctx, xs, n))
1760 return 0;
1761
1762 /*
1763 * Signal success at this depth. However, the previous error (if any)
1764 * is retained.
1765 */
1766 ctx->current_issuer = xi;
1767 ctx->current_cert = xs;
1768 ctx->error_depth = n;
1769 if (!ctx->verify_cb(1, ctx))
1770 return 0;
1771
1772 if (--n >= 0) {
1773 xi = xs;
1774 xs = sk_X509_value(ctx->chain, n);
1775 }
1776 }
1777 return 1;
1778}
1779
1780int X509_cmp_current_time(const ASN1_TIME *ctm)
1781{
1782 return X509_cmp_time(ctm, NULL);
1783}
1784
1785int X509_cmp_time(const ASN1_TIME *ctm, time_t *cmp_time)
1786{
1787 static const size_t utctime_length = sizeof("YYMMDDHHMMSSZ") - 1;
1788 static const size_t generalizedtime_length = sizeof("YYYYMMDDHHMMSSZ") - 1;
1789 ASN1_TIME *asn1_cmp_time = NULL;
1790 int i, day, sec, ret = 0;
1791#ifdef CHARSET_EBCDIC
1792 const char upper_z = 0x5A;
1793#else
1794 const char upper_z = 'Z';
1795#endif
1796 /*
1797 * Note that ASN.1 allows much more slack in the time format than RFC5280.
1798 * In RFC5280, the representation is fixed:
1799 * UTCTime: YYMMDDHHMMSSZ
1800 * GeneralizedTime: YYYYMMDDHHMMSSZ
1801 *
1802 * We do NOT currently enforce the following RFC 5280 requirement:
1803 * "CAs conforming to this profile MUST always encode certificate
1804 * validity dates through the year 2049 as UTCTime; certificate validity
1805 * dates in 2050 or later MUST be encoded as GeneralizedTime."
1806 */
1807 switch (ctm->type) {
1808 case V_ASN1_UTCTIME:
1809 if (ctm->length != (int)(utctime_length))
1810 return 0;
1811 break;
1812 case V_ASN1_GENERALIZEDTIME:
1813 if (ctm->length != (int)(generalizedtime_length))
1814 return 0;
1815 break;
1816 default:
1817 return 0;
1818 }
1819
1820 /**
1821 * Verify the format: the ASN.1 functions we use below allow a more
1822 * flexible format than what's mandated by RFC 5280.
1823 * Digit and date ranges will be verified in the conversion methods.
1824 */
1825 for (i = 0; i < ctm->length - 1; i++) {
1826 if (!ascii_isdigit(ctm->data[i]))
1827 return 0;
1828 }
1829 if (ctm->data[ctm->length - 1] != upper_z)
1830 return 0;
1831
1832 /*
1833 * There is ASN1_UTCTIME_cmp_time_t but no
1834 * ASN1_GENERALIZEDTIME_cmp_time_t or ASN1_TIME_cmp_time_t,
1835 * so we go through ASN.1
1836 */
1837 asn1_cmp_time = X509_time_adj(NULL, 0, cmp_time);
1838 if (asn1_cmp_time == NULL)
1839 goto err;
1840 if (!ASN1_TIME_diff(&day, &sec, ctm, asn1_cmp_time))
1841 goto err;
1842
1843 /*
1844 * X509_cmp_time comparison is <=.
1845 * The return value 0 is reserved for errors.
1846 */
1847 ret = (day >= 0 && sec >= 0) ? -1 : 1;
1848
1849 err:
1850 ASN1_TIME_free(asn1_cmp_time);
1851 return ret;
1852}
1853
1854/*
1855 * Return 0 if time should not be checked or reference time is in range,
1856 * or else 1 if it is past the end, or -1 if it is before the start
1857 */
1858int X509_cmp_timeframe(const X509_VERIFY_PARAM *vpm,
1859 const ASN1_TIME *start, const ASN1_TIME *end)
1860{
1861 time_t ref_time;
1862 time_t *time = NULL;
1863 unsigned long flags = vpm == NULL ? 0 : X509_VERIFY_PARAM_get_flags(vpm);
1864
1865 if ((flags & X509_V_FLAG_USE_CHECK_TIME) != 0) {
1866 ref_time = X509_VERIFY_PARAM_get_time(vpm);
1867 time = &ref_time;
1868 } else if ((flags & X509_V_FLAG_NO_CHECK_TIME) != 0) {
1869 return 0; /* this means ok */
1870 } /* else reference time is the current time */
1871
1872 if (end != NULL && X509_cmp_time(end, time) < 0)
1873 return 1;
1874 if (start != NULL && X509_cmp_time(start, time) > 0)
1875 return -1;
1876 return 0;
1877}
1878
1879ASN1_TIME *X509_gmtime_adj(ASN1_TIME *s, long adj)
1880{
1881 return X509_time_adj(s, adj, NULL);
1882}
1883
1884ASN1_TIME *X509_time_adj(ASN1_TIME *s, long offset_sec, time_t *in_tm)
1885{
1886 return X509_time_adj_ex(s, 0, offset_sec, in_tm);
1887}
1888
1889ASN1_TIME *X509_time_adj_ex(ASN1_TIME *s,
1890 int offset_day, long offset_sec, time_t *in_tm)
1891{
1892 time_t t;
1893
1894 if (in_tm)
1895 t = *in_tm;
1896 else
1897 time(&t);
1898
1899 if (s && !(s->flags & ASN1_STRING_FLAG_MSTRING)) {
1900 if (s->type == V_ASN1_UTCTIME)
1901 return ASN1_UTCTIME_adj(s, t, offset_day, offset_sec);
1902 if (s->type == V_ASN1_GENERALIZEDTIME)
1903 return ASN1_GENERALIZEDTIME_adj(s, t, offset_day, offset_sec);
1904 }
1905 return ASN1_TIME_adj(s, t, offset_day, offset_sec);
1906}
1907
1908int X509_get_pubkey_parameters(EVP_PKEY *pkey, STACK_OF(X509) *chain)
1909{
1910 EVP_PKEY *ktmp = NULL, *ktmp2;
1911 int i, j;
1912
1913 if ((pkey != NULL) && !EVP_PKEY_missing_parameters(pkey))
1914 return 1;
1915
1916 for (i = 0; i < sk_X509_num(chain); i++) {
1917 ktmp = X509_get0_pubkey(sk_X509_value(chain, i));
1918 if (ktmp == NULL) {
1919 X509err(X509_F_X509_GET_PUBKEY_PARAMETERS,
1920 X509_R_UNABLE_TO_GET_CERTS_PUBLIC_KEY);
1921 return 0;
1922 }
1923 if (!EVP_PKEY_missing_parameters(ktmp))
1924 break;
1925 }
1926 if (ktmp == NULL) {
1927 X509err(X509_F_X509_GET_PUBKEY_PARAMETERS,
1928 X509_R_UNABLE_TO_FIND_PARAMETERS_IN_CHAIN);
1929 return 0;
1930 }
1931
1932 /* first, populate the other certs */
1933 for (j = i - 1; j >= 0; j--) {
1934 ktmp2 = X509_get0_pubkey(sk_X509_value(chain, j));
1935 EVP_PKEY_copy_parameters(ktmp2, ktmp);
1936 }
1937
1938 if (pkey != NULL)
1939 EVP_PKEY_copy_parameters(pkey, ktmp);
1940 return 1;
1941}
1942
1943/* Make a delta CRL as the diff between two full CRLs */
1944
1945X509_CRL *X509_CRL_diff(X509_CRL *base, X509_CRL *newer,
1946 EVP_PKEY *skey, const EVP_MD *md, unsigned int flags)
1947{
1948 X509_CRL *crl = NULL;
1949 int i;
1950 STACK_OF(X509_REVOKED) *revs = NULL;
1951 /* CRLs can't be delta already */
1952 if (base->base_crl_number || newer->base_crl_number) {
1953 X509err(X509_F_X509_CRL_DIFF, X509_R_CRL_ALREADY_DELTA);
1954 return NULL;
1955 }
1956 /* Base and new CRL must have a CRL number */
1957 if (!base->crl_number || !newer->crl_number) {
1958 X509err(X509_F_X509_CRL_DIFF, X509_R_NO_CRL_NUMBER);
1959 return NULL;
1960 }
1961 /* Issuer names must match */
1962 if (X509_NAME_cmp(X509_CRL_get_issuer(base), X509_CRL_get_issuer(newer))) {
1963 X509err(X509_F_X509_CRL_DIFF, X509_R_ISSUER_MISMATCH);
1964 return NULL;
1965 }
1966 /* AKID and IDP must match */
1967 if (!crl_extension_match(base, newer, NID_authority_key_identifier)) {
1968 X509err(X509_F_X509_CRL_DIFF, X509_R_AKID_MISMATCH);
1969 return NULL;
1970 }
1971 if (!crl_extension_match(base, newer, NID_issuing_distribution_point)) {
1972 X509err(X509_F_X509_CRL_DIFF, X509_R_IDP_MISMATCH);
1973 return NULL;
1974 }
1975 /* Newer CRL number must exceed full CRL number */
1976 if (ASN1_INTEGER_cmp(newer->crl_number, base->crl_number) <= 0) {
1977 X509err(X509_F_X509_CRL_DIFF, X509_R_NEWER_CRL_NOT_NEWER);
1978 return NULL;
1979 }
1980 /* CRLs must verify */
1981 if (skey && (X509_CRL_verify(base, skey) <= 0 ||
1982 X509_CRL_verify(newer, skey) <= 0)) {
1983 X509err(X509_F_X509_CRL_DIFF, X509_R_CRL_VERIFY_FAILURE);
1984 return NULL;
1985 }
1986 /* Create new CRL */
1987 crl = X509_CRL_new();
1988 if (crl == NULL || !X509_CRL_set_version(crl, 1))
1989 goto memerr;
1990 /* Set issuer name */
1991 if (!X509_CRL_set_issuer_name(crl, X509_CRL_get_issuer(newer)))
1992 goto memerr;
1993
1994 if (!X509_CRL_set1_lastUpdate(crl, X509_CRL_get0_lastUpdate(newer)))
1995 goto memerr;
1996 if (!X509_CRL_set1_nextUpdate(crl, X509_CRL_get0_nextUpdate(newer)))
1997 goto memerr;
1998
1999 /* Set base CRL number: must be critical */
2000
2001 if (!X509_CRL_add1_ext_i2d(crl, NID_delta_crl, base->crl_number, 1, 0))
2002 goto memerr;
2003
2004 /*
2005 * Copy extensions across from newest CRL to delta: this will set CRL
2006 * number to correct value too.
2007 */
2008
2009 for (i = 0; i < X509_CRL_get_ext_count(newer); i++) {
2010 X509_EXTENSION *ext;
2011 ext = X509_CRL_get_ext(newer, i);
2012 if (!X509_CRL_add_ext(crl, ext, -1))
2013 goto memerr;
2014 }
2015
2016 /* Go through revoked entries, copying as needed */
2017
2018 revs = X509_CRL_get_REVOKED(newer);
2019
2020 for (i = 0; i < sk_X509_REVOKED_num(revs); i++) {
2021 X509_REVOKED *rvn, *rvtmp;
2022 rvn = sk_X509_REVOKED_value(revs, i);
2023 /*
2024 * Add only if not also in base. TODO: need something cleverer here
2025 * for some more complex CRLs covering multiple CAs.
2026 */
2027 if (!X509_CRL_get0_by_serial(base, &rvtmp, &rvn->serialNumber)) {
2028 rvtmp = X509_REVOKED_dup(rvn);
2029 if (!rvtmp)
2030 goto memerr;
2031 if (!X509_CRL_add0_revoked(crl, rvtmp)) {
2032 X509_REVOKED_free(rvtmp);
2033 goto memerr;
2034 }
2035 }
2036 }
2037 /* TODO: optionally prune deleted entries */
2038
2039 if (skey && md && !X509_CRL_sign(crl, skey, md))
2040 goto memerr;
2041
2042 return crl;
2043
2044 memerr:
2045 X509err(X509_F_X509_CRL_DIFF, ERR_R_MALLOC_FAILURE);
2046 X509_CRL_free(crl);
2047 return NULL;
2048}
2049
2050int X509_STORE_CTX_set_ex_data(X509_STORE_CTX *ctx, int idx, void *data)
2051{
2052 return CRYPTO_set_ex_data(&ctx->ex_data, idx, data);
2053}
2054
2055void *X509_STORE_CTX_get_ex_data(X509_STORE_CTX *ctx, int idx)
2056{
2057 return CRYPTO_get_ex_data(&ctx->ex_data, idx);
2058}
2059
2060int X509_STORE_CTX_get_error(X509_STORE_CTX *ctx)
2061{
2062 return ctx->error;
2063}
2064
2065void X509_STORE_CTX_set_error(X509_STORE_CTX *ctx, int err)
2066{
2067 ctx->error = err;
2068}
2069
2070int X509_STORE_CTX_get_error_depth(X509_STORE_CTX *ctx)
2071{
2072 return ctx->error_depth;
2073}
2074
2075void X509_STORE_CTX_set_error_depth(X509_STORE_CTX *ctx, int depth)
2076{
2077 ctx->error_depth = depth;
2078}
2079
2080X509 *X509_STORE_CTX_get_current_cert(X509_STORE_CTX *ctx)
2081{
2082 return ctx->current_cert;
2083}
2084
2085void X509_STORE_CTX_set_current_cert(X509_STORE_CTX *ctx, X509 *x)
2086{
2087 ctx->current_cert = x;
2088}
2089
2090STACK_OF(X509) *X509_STORE_CTX_get0_chain(X509_STORE_CTX *ctx)
2091{
2092 return ctx->chain;
2093}
2094
2095STACK_OF(X509) *X509_STORE_CTX_get1_chain(X509_STORE_CTX *ctx)
2096{
2097 if (!ctx->chain)
2098 return NULL;
2099 return X509_chain_up_ref(ctx->chain);
2100}
2101
2102X509 *X509_STORE_CTX_get0_current_issuer(X509_STORE_CTX *ctx)
2103{
2104 return ctx->current_issuer;
2105}
2106
2107X509_CRL *X509_STORE_CTX_get0_current_crl(X509_STORE_CTX *ctx)
2108{
2109 return ctx->current_crl;
2110}
2111
2112X509_STORE_CTX *X509_STORE_CTX_get0_parent_ctx(X509_STORE_CTX *ctx)
2113{
2114 return ctx->parent;
2115}
2116
2117void X509_STORE_CTX_set_cert(X509_STORE_CTX *ctx, X509 *x)
2118{
2119 ctx->cert = x;
2120}
2121
2122void X509_STORE_CTX_set0_crls(X509_STORE_CTX *ctx, STACK_OF(X509_CRL) *sk)
2123{
2124 ctx->crls = sk;
2125}
2126
2127int X509_STORE_CTX_set_purpose(X509_STORE_CTX *ctx, int purpose)
2128{
2129 /*
2130 * XXX: Why isn't this function always used to set the associated trust?
2131 * Should there even be a VPM->trust field at all? Or should the trust
2132 * always be inferred from the purpose by X509_STORE_CTX_init().
2133 */
2134 return X509_STORE_CTX_purpose_inherit(ctx, 0, purpose, 0);
2135}
2136
2137int X509_STORE_CTX_set_trust(X509_STORE_CTX *ctx, int trust)
2138{
2139 /*
2140 * XXX: See above, this function would only be needed when the default
2141 * trust for the purpose needs an override in a corner case.
2142 */
2143 return X509_STORE_CTX_purpose_inherit(ctx, 0, 0, trust);
2144}
2145
2146/*
2147 * This function is used to set the X509_STORE_CTX purpose and trust values.
2148 * This is intended to be used when another structure has its own trust and
2149 * purpose values which (if set) will be inherited by the ctx. If they aren't
2150 * set then we will usually have a default purpose in mind which should then
2151 * be used to set the trust value. An example of this is SSL use: an SSL
2152 * structure will have its own purpose and trust settings which the
2153 * application can set: if they aren't set then we use the default of SSL
2154 * client/server.
2155 */
2156
2157int X509_STORE_CTX_purpose_inherit(X509_STORE_CTX *ctx, int def_purpose,
2158 int purpose, int trust)
2159{
2160 int idx;
2161 /* If purpose not set use default */
2162 if (purpose == 0)
2163 purpose = def_purpose;
2164 /* If we have a purpose then check it is valid */
2165 if (purpose != 0) {
2166 X509_PURPOSE *ptmp;
2167 idx = X509_PURPOSE_get_by_id(purpose);
2168 if (idx == -1) {
2169 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2170 X509_R_UNKNOWN_PURPOSE_ID);
2171 return 0;
2172 }
2173 ptmp = X509_PURPOSE_get0(idx);
2174 if (ptmp->trust == X509_TRUST_DEFAULT) {
2175 idx = X509_PURPOSE_get_by_id(def_purpose);
2176 /*
2177 * XXX: In the two callers above def_purpose is always 0, which is
2178 * not a known value, so idx will always be -1. How is the
2179 * X509_TRUST_DEFAULT case actually supposed to be handled?
2180 */
2181 if (idx == -1) {
2182 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2183 X509_R_UNKNOWN_PURPOSE_ID);
2184 return 0;
2185 }
2186 ptmp = X509_PURPOSE_get0(idx);
2187 }
2188 /* If trust not set then get from purpose default */
2189 if (!trust)
2190 trust = ptmp->trust;
2191 }
2192 if (trust) {
2193 idx = X509_TRUST_get_by_id(trust);
2194 if (idx == -1) {
2195 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2196 X509_R_UNKNOWN_TRUST_ID);
2197 return 0;
2198 }
2199 }
2200
2201 if (purpose && !ctx->param->purpose)
2202 ctx->param->purpose = purpose;
2203 if (trust && !ctx->param->trust)
2204 ctx->param->trust = trust;
2205 return 1;
2206}
2207
2208X509_STORE_CTX *X509_STORE_CTX_new(void)
2209{
2210 X509_STORE_CTX *ctx = OPENSSL_zalloc(sizeof(*ctx));
2211
2212 if (ctx == NULL) {
2213 X509err(X509_F_X509_STORE_CTX_NEW, ERR_R_MALLOC_FAILURE);
2214 return NULL;
2215 }
2216 return ctx;
2217}
2218
2219void X509_STORE_CTX_free(X509_STORE_CTX *ctx)
2220{
2221 if (ctx == NULL)
2222 return;
2223
2224 X509_STORE_CTX_cleanup(ctx);
2225 OPENSSL_free(ctx);
2226}
2227
2228int X509_STORE_CTX_init(X509_STORE_CTX *ctx, X509_STORE *store, X509 *x509,
2229 STACK_OF(X509) *chain)
2230{
2231 int ret = 1;
2232
2233 ctx->store = store;
2234 ctx->cert = x509;
2235 ctx->untrusted = chain;
2236 ctx->crls = NULL;
2237 ctx->num_untrusted = 0;
2238 ctx->other_ctx = NULL;
2239 ctx->valid = 0;
2240 ctx->chain = NULL;
2241 ctx->error = 0;
2242 ctx->explicit_policy = 0;
2243 ctx->error_depth = 0;
2244 ctx->current_cert = NULL;
2245 ctx->current_issuer = NULL;
2246 ctx->current_crl = NULL;
2247 ctx->current_crl_score = 0;
2248 ctx->current_reasons = 0;
2249 ctx->tree = NULL;
2250 ctx->parent = NULL;
2251 ctx->dane = NULL;
2252 ctx->bare_ta_signed = 0;
2253 /* Zero ex_data to make sure we're cleanup-safe */
2254 memset(&ctx->ex_data, 0, sizeof(ctx->ex_data));
2255
2256 /* store->cleanup is always 0 in OpenSSL, if set must be idempotent */
2257 if (store)
2258 ctx->cleanup = store->cleanup;
2259 else
2260 ctx->cleanup = 0;
2261
2262 if (store && store->check_issued)
2263 ctx->check_issued = store->check_issued;
2264 else
2265 ctx->check_issued = check_issued;
2266
2267 if (store && store->get_issuer)
2268 ctx->get_issuer = store->get_issuer;
2269 else
2270 ctx->get_issuer = X509_STORE_CTX_get1_issuer;
2271
2272 if (store && store->verify_cb)
2273 ctx->verify_cb = store->verify_cb;
2274 else
2275 ctx->verify_cb = null_callback;
2276
2277 if (store && store->verify)
2278 ctx->verify = store->verify;
2279 else
2280 ctx->verify = internal_verify;
2281
2282 if (store && store->check_revocation)
2283 ctx->check_revocation = store->check_revocation;
2284 else
2285 ctx->check_revocation = check_revocation;
2286
2287 if (store && store->get_crl)
2288 ctx->get_crl = store->get_crl;
2289 else
2290 ctx->get_crl = NULL;
2291
2292 if (store && store->check_crl)
2293 ctx->check_crl = store->check_crl;
2294 else
2295 ctx->check_crl = check_crl;
2296
2297 if (store && store->cert_crl)
2298 ctx->cert_crl = store->cert_crl;
2299 else
2300 ctx->cert_crl = cert_crl;
2301
2302 if (store && store->check_policy)
2303 ctx->check_policy = store->check_policy;
2304 else
2305 ctx->check_policy = check_policy;
2306
2307 if (store && store->lookup_certs)
2308 ctx->lookup_certs = store->lookup_certs;
2309 else
2310 ctx->lookup_certs = X509_STORE_CTX_get1_certs;
2311
2312 if (store && store->lookup_crls)
2313 ctx->lookup_crls = store->lookup_crls;
2314 else
2315 ctx->lookup_crls = X509_STORE_CTX_get1_crls;
2316
2317 ctx->param = X509_VERIFY_PARAM_new();
2318 if (ctx->param == NULL) {
2319 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2320 goto err;
2321 }
2322
2323 /*
2324 * Inherit callbacks and flags from X509_STORE if not set use defaults.
2325 */
2326 if (store)
2327 ret = X509_VERIFY_PARAM_inherit(ctx->param, store->param);
2328 else
2329 ctx->param->inh_flags |= X509_VP_FLAG_DEFAULT | X509_VP_FLAG_ONCE;
2330
2331 if (ret)
2332 ret = X509_VERIFY_PARAM_inherit(ctx->param,
2333 X509_VERIFY_PARAM_lookup("default"));
2334
2335 if (ret == 0) {
2336 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2337 goto err;
2338 }
2339
2340 /*
2341 * XXX: For now, continue to inherit trust from VPM, but infer from the
2342 * purpose if this still yields the default value.
2343 */
2344 if (ctx->param->trust == X509_TRUST_DEFAULT) {
2345 int idx = X509_PURPOSE_get_by_id(ctx->param->purpose);
2346 X509_PURPOSE *xp = X509_PURPOSE_get0(idx);
2347
2348 if (xp != NULL)
2349 ctx->param->trust = X509_PURPOSE_get_trust(xp);
2350 }
2351
2352 if (CRYPTO_new_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx,
2353 &ctx->ex_data))
2354 return 1;
2355 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2356
2357 err:
2358 /*
2359 * On error clean up allocated storage, if the store context was not
2360 * allocated with X509_STORE_CTX_new() this is our last chance to do so.
2361 */
2362 X509_STORE_CTX_cleanup(ctx);
2363 return 0;
2364}
2365
2366/*
2367 * Set alternative lookup method: just a STACK of trusted certificates. This
2368 * avoids X509_STORE nastiness where it isn't needed.
2369 */
2370void X509_STORE_CTX_set0_trusted_stack(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2371{
2372 ctx->other_ctx = sk;
2373 ctx->get_issuer = get_issuer_sk;
2374 ctx->lookup_certs = lookup_certs_sk;
2375}
2376
2377void X509_STORE_CTX_cleanup(X509_STORE_CTX *ctx)
2378{
2379 /*
2380 * We need to be idempotent because, unfortunately, free() also calls
2381 * cleanup(), so the natural call sequence new(), init(), cleanup(), free()
2382 * calls cleanup() for the same object twice! Thus we must zero the
2383 * pointers below after they're freed!
2384 */
2385 /* Seems to always be 0 in OpenSSL, do this at most once. */
2386 if (ctx->cleanup != NULL) {
2387 ctx->cleanup(ctx);
2388 ctx->cleanup = NULL;
2389 }
2390 if (ctx->param != NULL) {
2391 if (ctx->parent == NULL)
2392 X509_VERIFY_PARAM_free(ctx->param);
2393 ctx->param = NULL;
2394 }
2395 X509_policy_tree_free(ctx->tree);
2396 ctx->tree = NULL;
2397 sk_X509_pop_free(ctx->chain, X509_free);
2398 ctx->chain = NULL;
2399 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx, &(ctx->ex_data));
2400 memset(&ctx->ex_data, 0, sizeof(ctx->ex_data));
2401}
2402
2403void X509_STORE_CTX_set_depth(X509_STORE_CTX *ctx, int depth)
2404{
2405 X509_VERIFY_PARAM_set_depth(ctx->param, depth);
2406}
2407
2408void X509_STORE_CTX_set_flags(X509_STORE_CTX *ctx, unsigned long flags)
2409{
2410 X509_VERIFY_PARAM_set_flags(ctx->param, flags);
2411}
2412
2413void X509_STORE_CTX_set_time(X509_STORE_CTX *ctx, unsigned long flags,
2414 time_t t)
2415{
2416 X509_VERIFY_PARAM_set_time(ctx->param, t);
2417}
2418
2419X509 *X509_STORE_CTX_get0_cert(X509_STORE_CTX *ctx)
2420{
2421 return ctx->cert;
2422}
2423
2424STACK_OF(X509) *X509_STORE_CTX_get0_untrusted(X509_STORE_CTX *ctx)
2425{
2426 return ctx->untrusted;
2427}
2428
2429void X509_STORE_CTX_set0_untrusted(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2430{
2431 ctx->untrusted = sk;
2432}
2433
2434void X509_STORE_CTX_set0_verified_chain(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2435{
2436 sk_X509_pop_free(ctx->chain, X509_free);
2437 ctx->chain = sk;
2438}
2439
2440void X509_STORE_CTX_set_verify_cb(X509_STORE_CTX *ctx,
2441 X509_STORE_CTX_verify_cb verify_cb)
2442{
2443 ctx->verify_cb = verify_cb;
2444}
2445
2446X509_STORE_CTX_verify_cb X509_STORE_CTX_get_verify_cb(X509_STORE_CTX *ctx)
2447{
2448 return ctx->verify_cb;
2449}
2450
2451void X509_STORE_CTX_set_verify(X509_STORE_CTX *ctx,
2452 X509_STORE_CTX_verify_fn verify)
2453{
2454 ctx->verify = verify;
2455}
2456
2457X509_STORE_CTX_verify_fn X509_STORE_CTX_get_verify(X509_STORE_CTX *ctx)
2458{
2459 return ctx->verify;
2460}
2461
2462X509_STORE_CTX_get_issuer_fn X509_STORE_CTX_get_get_issuer(X509_STORE_CTX *ctx)
2463{
2464 return ctx->get_issuer;
2465}
2466
2467X509_STORE_CTX_check_issued_fn X509_STORE_CTX_get_check_issued(X509_STORE_CTX *ctx)
2468{
2469 return ctx->check_issued;
2470}
2471
2472X509_STORE_CTX_check_revocation_fn X509_STORE_CTX_get_check_revocation(X509_STORE_CTX *ctx)
2473{
2474 return ctx->check_revocation;
2475}
2476
2477X509_STORE_CTX_get_crl_fn X509_STORE_CTX_get_get_crl(X509_STORE_CTX *ctx)
2478{
2479 return ctx->get_crl;
2480}
2481
2482X509_STORE_CTX_check_crl_fn X509_STORE_CTX_get_check_crl(X509_STORE_CTX *ctx)
2483{
2484 return ctx->check_crl;
2485}
2486
2487X509_STORE_CTX_cert_crl_fn X509_STORE_CTX_get_cert_crl(X509_STORE_CTX *ctx)
2488{
2489 return ctx->cert_crl;
2490}
2491
2492X509_STORE_CTX_check_policy_fn X509_STORE_CTX_get_check_policy(X509_STORE_CTX *ctx)
2493{
2494 return ctx->check_policy;
2495}
2496
2497X509_STORE_CTX_lookup_certs_fn X509_STORE_CTX_get_lookup_certs(X509_STORE_CTX *ctx)
2498{
2499 return ctx->lookup_certs;
2500}
2501
2502X509_STORE_CTX_lookup_crls_fn X509_STORE_CTX_get_lookup_crls(X509_STORE_CTX *ctx)
2503{
2504 return ctx->lookup_crls;
2505}
2506
2507X509_STORE_CTX_cleanup_fn X509_STORE_CTX_get_cleanup(X509_STORE_CTX *ctx)
2508{
2509 return ctx->cleanup;
2510}
2511
2512X509_POLICY_TREE *X509_STORE_CTX_get0_policy_tree(X509_STORE_CTX *ctx)
2513{
2514 return ctx->tree;
2515}
2516
2517int X509_STORE_CTX_get_explicit_policy(X509_STORE_CTX *ctx)
2518{
2519 return ctx->explicit_policy;
2520}
2521
2522int X509_STORE_CTX_get_num_untrusted(X509_STORE_CTX *ctx)
2523{
2524 return ctx->num_untrusted;
2525}
2526
2527int X509_STORE_CTX_set_default(X509_STORE_CTX *ctx, const char *name)
2528{
2529 const X509_VERIFY_PARAM *param;
2530
2531 param = X509_VERIFY_PARAM_lookup(name);
2532 if (param == NULL)
2533 return 0;
2534 return X509_VERIFY_PARAM_inherit(ctx->param, param);
2535}
2536
2537X509_VERIFY_PARAM *X509_STORE_CTX_get0_param(X509_STORE_CTX *ctx)
2538{
2539 return ctx->param;
2540}
2541
2542void X509_STORE_CTX_set0_param(X509_STORE_CTX *ctx, X509_VERIFY_PARAM *param)
2543{
2544 X509_VERIFY_PARAM_free(ctx->param);
2545 ctx->param = param;
2546}
2547
2548void X509_STORE_CTX_set0_dane(X509_STORE_CTX *ctx, SSL_DANE *dane)
2549{
2550 ctx->dane = dane;
2551}
2552
2553static unsigned char *dane_i2d(
2554 X509 *cert,
2555 uint8_t selector,
2556 unsigned int *i2dlen)
2557{
2558 unsigned char *buf = NULL;
2559 int len;
2560
2561 /*
2562 * Extract ASN.1 DER form of certificate or public key.
2563 */
2564 switch (selector) {
2565 case DANETLS_SELECTOR_CERT:
2566 len = i2d_X509(cert, &buf);
2567 break;
2568 case DANETLS_SELECTOR_SPKI:
2569 len = i2d_X509_PUBKEY(X509_get_X509_PUBKEY(cert), &buf);
2570 break;
2571 default:
2572 X509err(X509_F_DANE_I2D, X509_R_BAD_SELECTOR);
2573 return NULL;
2574 }
2575
2576 if (len < 0 || buf == NULL) {
2577 X509err(X509_F_DANE_I2D, ERR_R_MALLOC_FAILURE);
2578 return NULL;
2579 }
2580
2581 *i2dlen = (unsigned int)len;
2582 return buf;
2583}
2584
2585#define DANETLS_NONE 256 /* impossible uint8_t */
2586
2587static int dane_match(X509_STORE_CTX *ctx, X509 *cert, int depth)
2588{
2589 SSL_DANE *dane = ctx->dane;
2590 unsigned usage = DANETLS_NONE;
2591 unsigned selector = DANETLS_NONE;
2592 unsigned ordinal = DANETLS_NONE;
2593 unsigned mtype = DANETLS_NONE;
2594 unsigned char *i2dbuf = NULL;
2595 unsigned int i2dlen = 0;
2596 unsigned char mdbuf[EVP_MAX_MD_SIZE];
2597 unsigned char *cmpbuf = NULL;
2598 unsigned int cmplen = 0;
2599 int i;
2600 int recnum;
2601 int matched = 0;
2602 danetls_record *t = NULL;
2603 uint32_t mask;
2604
2605 mask = (depth == 0) ? DANETLS_EE_MASK : DANETLS_TA_MASK;
2606
2607 /*
2608 * The trust store is not applicable with DANE-TA(2)
2609 */
2610 if (depth >= ctx->num_untrusted)
2611 mask &= DANETLS_PKIX_MASK;
2612
2613 /*
2614 * If we've previously matched a PKIX-?? record, no need to test any
2615 * further PKIX-?? records, it remains to just build the PKIX chain.
2616 * Had the match been a DANE-?? record, we'd be done already.
2617 */
2618 if (dane->mdpth >= 0)
2619 mask &= ~DANETLS_PKIX_MASK;
2620
2621 /*-
2622 * https://tools.ietf.org/html/rfc7671#section-5.1
2623 * https://tools.ietf.org/html/rfc7671#section-5.2
2624 * https://tools.ietf.org/html/rfc7671#section-5.3
2625 * https://tools.ietf.org/html/rfc7671#section-5.4
2626 *
2627 * We handle DANE-EE(3) records first as they require no chain building
2628 * and no expiration or hostname checks. We also process digests with
2629 * higher ordinals first and ignore lower priorities except Full(0) which
2630 * is always processed (last). If none match, we then process PKIX-EE(1).
2631 *
2632 * NOTE: This relies on DANE usages sorting before the corresponding PKIX
2633 * usages in SSL_dane_tlsa_add(), and also on descending sorting of digest
2634 * priorities. See twin comment in ssl/ssl_lib.c.
2635 *
2636 * We expect that most TLSA RRsets will have just a single usage, so we
2637 * don't go out of our way to cache multiple selector-specific i2d buffers
2638 * across usages, but if the selector happens to remain the same as switch
2639 * usages, that's OK. Thus, a set of "3 1 1", "3 0 1", "1 1 1", "1 0 1",
2640 * records would result in us generating each of the certificate and public
2641 * key DER forms twice, but more typically we'd just see multiple "3 1 1"
2642 * or multiple "3 0 1" records.
2643 *
2644 * As soon as we find a match at any given depth, we stop, because either
2645 * we've matched a DANE-?? record and the peer is authenticated, or, after
2646 * exhausting all DANE-?? records, we've matched a PKIX-?? record, which is
2647 * sufficient for DANE, and what remains to do is ordinary PKIX validation.
2648 */
2649 recnum = (dane->umask & mask) ? sk_danetls_record_num(dane->trecs) : 0;
2650 for (i = 0; matched == 0 && i < recnum; ++i) {
2651 t = sk_danetls_record_value(dane->trecs, i);
2652 if ((DANETLS_USAGE_BIT(t->usage) & mask) == 0)
2653 continue;
2654 if (t->usage != usage) {
2655 usage = t->usage;
2656
2657 /* Reset digest agility for each usage/selector pair */
2658 mtype = DANETLS_NONE;
2659 ordinal = dane->dctx->mdord[t->mtype];
2660 }
2661 if (t->selector != selector) {
2662 selector = t->selector;
2663
2664 /* Update per-selector state */
2665 OPENSSL_free(i2dbuf);
2666 i2dbuf = dane_i2d(cert, selector, &i2dlen);
2667 if (i2dbuf == NULL)
2668 return -1;
2669
2670 /* Reset digest agility for each usage/selector pair */
2671 mtype = DANETLS_NONE;
2672 ordinal = dane->dctx->mdord[t->mtype];
2673 } else if (t->mtype != DANETLS_MATCHING_FULL) {
2674 /*-
2675 * Digest agility:
2676 *
2677 * <https://tools.ietf.org/html/rfc7671#section-9>
2678 *
2679 * For a fixed selector, after processing all records with the
2680 * highest mtype ordinal, ignore all mtypes with lower ordinals
2681 * other than "Full".
2682 */
2683 if (dane->dctx->mdord[t->mtype] < ordinal)
2684 continue;
2685 }
2686
2687 /*
2688 * Each time we hit a (new selector or) mtype, re-compute the relevant
2689 * digest, more complex caching is not worth the code space.
2690 */
2691 if (t->mtype != mtype) {
2692 const EVP_MD *md = dane->dctx->mdevp[mtype = t->mtype];
2693 cmpbuf = i2dbuf;
2694 cmplen = i2dlen;
2695
2696 if (md != NULL) {
2697 cmpbuf = mdbuf;
2698 if (!EVP_Digest(i2dbuf, i2dlen, cmpbuf, &cmplen, md, 0)) {
2699 matched = -1;
2700 break;
2701 }
2702 }
2703 }
2704
2705 /*
2706 * Squirrel away the certificate and depth if we have a match. Any
2707 * DANE match is dispositive, but with PKIX we still need to build a
2708 * full chain.
2709 */
2710 if (cmplen == t->dlen &&
2711 memcmp(cmpbuf, t->data, cmplen) == 0) {
2712 if (DANETLS_USAGE_BIT(usage) & DANETLS_DANE_MASK)
2713 matched = 1;
2714 if (matched || dane->mdpth < 0) {
2715 dane->mdpth = depth;
2716 dane->mtlsa = t;
2717 OPENSSL_free(dane->mcert);
2718 dane->mcert = cert;
2719 X509_up_ref(cert);
2720 }
2721 break;
2722 }
2723 }
2724
2725 /* Clear the one-element DER cache */
2726 OPENSSL_free(i2dbuf);
2727 return matched;
2728}
2729
2730static int check_dane_issuer(X509_STORE_CTX *ctx, int depth)
2731{
2732 SSL_DANE *dane = ctx->dane;
2733 int matched = 0;
2734 X509 *cert;
2735
2736 if (!DANETLS_HAS_TA(dane) || depth == 0)
2737 return X509_TRUST_UNTRUSTED;
2738
2739 /*
2740 * Record any DANE trust-anchor matches, for the first depth to test, if
2741 * there's one at that depth. (This'll be false for length 1 chains looking
2742 * for an exact match for the leaf certificate).
2743 */
2744 cert = sk_X509_value(ctx->chain, depth);
2745 if (cert != NULL && (matched = dane_match(ctx, cert, depth)) < 0)
2746 return X509_TRUST_REJECTED;
2747 if (matched > 0) {
2748 ctx->num_untrusted = depth - 1;
2749 return X509_TRUST_TRUSTED;
2750 }
2751
2752 return X509_TRUST_UNTRUSTED;
2753}
2754
2755static int check_dane_pkeys(X509_STORE_CTX *ctx)
2756{
2757 SSL_DANE *dane = ctx->dane;
2758 danetls_record *t;
2759 int num = ctx->num_untrusted;
2760 X509 *cert = sk_X509_value(ctx->chain, num - 1);
2761 int recnum = sk_danetls_record_num(dane->trecs);
2762 int i;
2763
2764 for (i = 0; i < recnum; ++i) {
2765 t = sk_danetls_record_value(dane->trecs, i);
2766 if (t->usage != DANETLS_USAGE_DANE_TA ||
2767 t->selector != DANETLS_SELECTOR_SPKI ||
2768 t->mtype != DANETLS_MATCHING_FULL ||
2769 X509_verify(cert, t->spki) <= 0)
2770 continue;
2771
2772 /* Clear any PKIX-?? matches that failed to extend to a full chain */
2773 X509_free(dane->mcert);
2774 dane->mcert = NULL;
2775
2776 /* Record match via a bare TA public key */
2777 ctx->bare_ta_signed = 1;
2778 dane->mdpth = num - 1;
2779 dane->mtlsa = t;
2780
2781 /* Prune any excess chain certificates */
2782 num = sk_X509_num(ctx->chain);
2783 for (; num > ctx->num_untrusted; --num)
2784 X509_free(sk_X509_pop(ctx->chain));
2785
2786 return X509_TRUST_TRUSTED;
2787 }
2788
2789 return X509_TRUST_UNTRUSTED;
2790}
2791
2792static void dane_reset(SSL_DANE *dane)
2793{
2794 /*
2795 * Reset state to verify another chain, or clear after failure.
2796 */
2797 X509_free(dane->mcert);
2798 dane->mcert = NULL;
2799 dane->mtlsa = NULL;
2800 dane->mdpth = -1;
2801 dane->pdpth = -1;
2802}
2803
2804static int check_leaf_suiteb(X509_STORE_CTX *ctx, X509 *cert)
2805{
2806 int err = X509_chain_check_suiteb(NULL, cert, NULL, ctx->param->flags);
2807
2808 if (err == X509_V_OK)
2809 return 1;
2810 return verify_cb_cert(ctx, cert, 0, err);
2811}
2812
2813static int dane_verify(X509_STORE_CTX *ctx)
2814{
2815 X509 *cert = ctx->cert;
2816 SSL_DANE *dane = ctx->dane;
2817 int matched;
2818 int done;
2819
2820 dane_reset(dane);
2821
2822 /*-
2823 * When testing the leaf certificate, if we match a DANE-EE(3) record,
2824 * dane_match() returns 1 and we're done. If however we match a PKIX-EE(1)
2825 * record, the match depth and matching TLSA record are recorded, but the
2826 * return value is 0, because we still need to find a PKIX trust-anchor.
2827 * Therefore, when DANE authentication is enabled (required), we're done
2828 * if:
2829 * + matched < 0, internal error.
2830 * + matched == 1, we matched a DANE-EE(3) record
2831 * + matched == 0, mdepth < 0 (no PKIX-EE match) and there are no
2832 * DANE-TA(2) or PKIX-TA(0) to test.
2833 */
2834 matched = dane_match(ctx, ctx->cert, 0);
2835 done = matched != 0 || (!DANETLS_HAS_TA(dane) && dane->mdpth < 0);
2836
2837 if (done)
2838 X509_get_pubkey_parameters(NULL, ctx->chain);
2839
2840 if (matched > 0) {
2841 /* Callback invoked as needed */
2842 if (!check_leaf_suiteb(ctx, cert))
2843 return 0;
2844 /* Callback invoked as needed */
2845 if ((dane->flags & DANE_FLAG_NO_DANE_EE_NAMECHECKS) == 0 &&
2846 !check_id(ctx))
2847 return 0;
2848 /* Bypass internal_verify(), issue depth 0 success callback */
2849 ctx->error_depth = 0;
2850 ctx->current_cert = cert;
2851 return ctx->verify_cb(1, ctx);
2852 }
2853
2854 if (matched < 0) {
2855 ctx->error_depth = 0;
2856 ctx->current_cert = cert;
2857 ctx->error = X509_V_ERR_OUT_OF_MEM;
2858 return -1;
2859 }
2860
2861 if (done) {
2862 /* Fail early, TA-based success is not possible */
2863 if (!check_leaf_suiteb(ctx, cert))
2864 return 0;
2865 return verify_cb_cert(ctx, cert, 0, X509_V_ERR_DANE_NO_MATCH);
2866 }
2867
2868 /*
2869 * Chain verification for usages 0/1/2. TLSA record matching of depth > 0
2870 * certificates happens in-line with building the rest of the chain.
2871 */
2872 return verify_chain(ctx);
2873}
2874
2875/* Get issuer, without duplicate suppression */
2876static int get_issuer(X509 **issuer, X509_STORE_CTX *ctx, X509 *cert)
2877{
2878 STACK_OF(X509) *saved_chain = ctx->chain;
2879 int ok;
2880
2881 ctx->chain = NULL;
2882 ok = ctx->get_issuer(issuer, ctx, cert);
2883 ctx->chain = saved_chain;
2884
2885 return ok;
2886}
2887
2888static int build_chain(X509_STORE_CTX *ctx)
2889{
2890 SSL_DANE *dane = ctx->dane;
2891 int num = sk_X509_num(ctx->chain);
2892 X509 *cert = sk_X509_value(ctx->chain, num - 1);
2893 int ss = cert_self_signed(cert);
2894 STACK_OF(X509) *sktmp = NULL;
2895 unsigned int search;
2896 int may_trusted = 0;
2897 int may_alternate = 0;
2898 int trust = X509_TRUST_UNTRUSTED;
2899 int alt_untrusted = 0;
2900 int depth;
2901 int ok = 0;
2902 int i;
2903
2904 /* Our chain starts with a single untrusted element. */
2905 if (!ossl_assert(num == 1 && ctx->num_untrusted == num)) {
2906 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
2907 ctx->error = X509_V_ERR_UNSPECIFIED;
2908 return 0;
2909 }
2910
2911#define S_DOUNTRUSTED (1 << 0) /* Search untrusted chain */
2912#define S_DOTRUSTED (1 << 1) /* Search trusted store */
2913#define S_DOALTERNATE (1 << 2) /* Retry with pruned alternate chain */
2914 /*
2915 * Set up search policy, untrusted if possible, trusted-first if enabled.
2916 * If we're doing DANE and not doing PKIX-TA/PKIX-EE, we never look in the
2917 * trust_store, otherwise we might look there first. If not trusted-first,
2918 * and alternate chains are not disabled, try building an alternate chain
2919 * if no luck with untrusted first.
2920 */
2921 search = (ctx->untrusted != NULL) ? S_DOUNTRUSTED : 0;
2922 if (DANETLS_HAS_PKIX(dane) || !DANETLS_HAS_DANE(dane)) {
2923 if (search == 0 || ctx->param->flags & X509_V_FLAG_TRUSTED_FIRST)
2924 search |= S_DOTRUSTED;
2925 else if (!(ctx->param->flags & X509_V_FLAG_NO_ALT_CHAINS))
2926 may_alternate = 1;
2927 may_trusted = 1;
2928 }
2929
2930 /*
2931 * Shallow-copy the stack of untrusted certificates (with TLS, this is
2932 * typically the content of the peer's certificate message) so can make
2933 * multiple passes over it, while free to remove elements as we go.
2934 */
2935 if (ctx->untrusted && (sktmp = sk_X509_dup(ctx->untrusted)) == NULL) {
2936 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2937 ctx->error = X509_V_ERR_OUT_OF_MEM;
2938 return 0;
2939 }
2940
2941 /*
2942 * If we got any "DANE-TA(2) Cert(0) Full(0)" trust-anchors from DNS, add
2943 * them to our working copy of the untrusted certificate stack. Since the
2944 * caller of X509_STORE_CTX_init() may have provided only a leaf cert with
2945 * no corresponding stack of untrusted certificates, we may need to create
2946 * an empty stack first. [ At present only the ssl library provides DANE
2947 * support, and ssl_verify_cert_chain() always provides a non-null stack
2948 * containing at least the leaf certificate, but we must be prepared for
2949 * this to change. ]
2950 */
2951 if (DANETLS_ENABLED(dane) && dane->certs != NULL) {
2952 if (sktmp == NULL && (sktmp = sk_X509_new_null()) == NULL) {
2953 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2954 ctx->error = X509_V_ERR_OUT_OF_MEM;
2955 return 0;
2956 }
2957 for (i = 0; i < sk_X509_num(dane->certs); ++i) {
2958 if (!sk_X509_push(sktmp, sk_X509_value(dane->certs, i))) {
2959 sk_X509_free(sktmp);
2960 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2961 ctx->error = X509_V_ERR_OUT_OF_MEM;
2962 return 0;
2963 }
2964 }
2965 }
2966
2967 /*
2968 * Still absurdly large, but arithmetically safe, a lower hard upper bound
2969 * might be reasonable.
2970 */
2971 if (ctx->param->depth > INT_MAX/2)
2972 ctx->param->depth = INT_MAX/2;
2973
2974 /*
2975 * Try to Extend the chain until we reach an ultimately trusted issuer.
2976 * Build chains up to one longer the limit, later fail if we hit the limit,
2977 * with an X509_V_ERR_CERT_CHAIN_TOO_LONG error code.
2978 */
2979 depth = ctx->param->depth + 1;
2980
2981 while (search != 0) {
2982 X509 *x;
2983 X509 *xtmp = NULL;
2984
2985 /*
2986 * Look in the trust store if enabled for first lookup, or we've run
2987 * out of untrusted issuers and search here is not disabled. When we
2988 * reach the depth limit, we stop extending the chain, if by that point
2989 * we've not found a trust-anchor, any trusted chain would be too long.
2990 *
2991 * The error reported to the application verify callback is at the
2992 * maximal valid depth with the current certificate equal to the last
2993 * not ultimately-trusted issuer. For example, with verify_depth = 0,
2994 * the callback will report errors at depth=1 when the immediate issuer
2995 * of the leaf certificate is not a trust anchor. No attempt will be
2996 * made to locate an issuer for that certificate, since such a chain
2997 * would be a-priori too long.
2998 */
2999 if ((search & S_DOTRUSTED) != 0) {
3000 i = num = sk_X509_num(ctx->chain);
3001 if ((search & S_DOALTERNATE) != 0) {
3002 /*
3003 * As high up the chain as we can, look for an alternative
3004 * trusted issuer of an untrusted certificate that currently
3005 * has an untrusted issuer. We use the alt_untrusted variable
3006 * to track how far up the chain we find the first match. It
3007 * is only if and when we find a match, that we prune the chain
3008 * and reset ctx->num_untrusted to the reduced count of
3009 * untrusted certificates. While we're searching for such a
3010 * match (which may never be found), it is neither safe nor
3011 * wise to preemptively modify either the chain or
3012 * ctx->num_untrusted.
3013 *
3014 * Note, like ctx->num_untrusted, alt_untrusted is a count of
3015 * untrusted certificates, not a "depth".
3016 */
3017 i = alt_untrusted;
3018 }
3019 x = sk_X509_value(ctx->chain, i-1);
3020
3021 ok = (depth < num) ? 0 : get_issuer(&xtmp, ctx, x);
3022
3023 if (ok < 0) {
3024 trust = X509_TRUST_REJECTED;
3025 ctx->error = X509_V_ERR_STORE_LOOKUP;
3026 search = 0;
3027 continue;
3028 }
3029
3030 if (ok > 0) {
3031 /*
3032 * Alternative trusted issuer for a mid-chain untrusted cert?
3033 * Pop the untrusted cert's successors and retry. We might now
3034 * be able to complete a valid chain via the trust store. Note
3035 * that despite the current trust-store match we might still
3036 * fail complete the chain to a suitable trust-anchor, in which
3037 * case we may prune some more untrusted certificates and try
3038 * again. Thus the S_DOALTERNATE bit may yet be turned on
3039 * again with an even shorter untrusted chain!
3040 *
3041 * If in the process we threw away our matching PKIX-TA trust
3042 * anchor, reset DANE trust. We might find a suitable trusted
3043 * certificate among the ones from the trust store.
3044 */
3045 if ((search & S_DOALTERNATE) != 0) {
3046 if (!ossl_assert(num > i && i > 0 && ss == 0)) {
3047 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
3048 X509_free(xtmp);
3049 trust = X509_TRUST_REJECTED;
3050 ctx->error = X509_V_ERR_UNSPECIFIED;
3051 search = 0;
3052 continue;
3053 }
3054 search &= ~S_DOALTERNATE;
3055 for (; num > i; --num)
3056 X509_free(sk_X509_pop(ctx->chain));
3057 ctx->num_untrusted = num;
3058
3059 if (DANETLS_ENABLED(dane) &&
3060 dane->mdpth >= ctx->num_untrusted) {
3061 dane->mdpth = -1;
3062 X509_free(dane->mcert);
3063 dane->mcert = NULL;
3064 }
3065 if (DANETLS_ENABLED(dane) &&
3066 dane->pdpth >= ctx->num_untrusted)
3067 dane->pdpth = -1;
3068 }
3069
3070 /*
3071 * Self-signed untrusted certificates get replaced by their
3072 * trusted matching issuer. Otherwise, grow the chain.
3073 */
3074 if (ss == 0) {
3075 if (!sk_X509_push(ctx->chain, x = xtmp)) {
3076 X509_free(xtmp);
3077 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
3078 trust = X509_TRUST_REJECTED;
3079 ctx->error = X509_V_ERR_OUT_OF_MEM;
3080 search = 0;
3081 continue;
3082 }
3083 ss = cert_self_signed(x);
3084 } else if (num == ctx->num_untrusted) {
3085 /*
3086 * We have a self-signed certificate that has the same
3087 * subject name (and perhaps keyid and/or serial number) as
3088 * a trust-anchor. We must have an exact match to avoid
3089 * possible impersonation via key substitution etc.
3090 */
3091 if (X509_cmp(x, xtmp) != 0) {
3092 /* Self-signed untrusted mimic. */
3093 X509_free(xtmp);
3094 ok = 0;
3095 } else {
3096 X509_free(x);
3097 ctx->num_untrusted = --num;
3098 (void) sk_X509_set(ctx->chain, num, x = xtmp);
3099 }
3100 }
3101
3102 /*
3103 * We've added a new trusted certificate to the chain, recheck
3104 * trust. If not done, and not self-signed look deeper.
3105 * Whether or not we're doing "trusted first", we no longer
3106 * look for untrusted certificates from the peer's chain.
3107 *
3108 * At this point ctx->num_trusted and num must reflect the
3109 * correct number of untrusted certificates, since the DANE
3110 * logic in check_trust() depends on distinguishing CAs from
3111 * "the wire" from CAs from the trust store. In particular, the
3112 * certificate at depth "num" should be the new trusted
3113 * certificate with ctx->num_untrusted <= num.
3114 */
3115 if (ok) {
3116 if (!ossl_assert(ctx->num_untrusted <= num)) {
3117 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
3118 trust = X509_TRUST_REJECTED;
3119 ctx->error = X509_V_ERR_UNSPECIFIED;
3120 search = 0;
3121 continue;
3122 }
3123 search &= ~S_DOUNTRUSTED;
3124 switch (trust = check_trust(ctx, num)) {
3125 case X509_TRUST_TRUSTED:
3126 case X509_TRUST_REJECTED:
3127 search = 0;
3128 continue;
3129 }
3130 if (ss == 0)
3131 continue;
3132 }
3133 }
3134
3135 /*
3136 * No dispositive decision, and either self-signed or no match, if
3137 * we were doing untrusted-first, and alt-chains are not disabled,
3138 * do that, by repeatedly losing one untrusted element at a time,
3139 * and trying to extend the shorted chain.
3140 */
3141 if ((search & S_DOUNTRUSTED) == 0) {
3142 /* Continue search for a trusted issuer of a shorter chain? */
3143 if ((search & S_DOALTERNATE) != 0 && --alt_untrusted > 0)
3144 continue;
3145 /* Still no luck and no fallbacks left? */
3146 if (!may_alternate || (search & S_DOALTERNATE) != 0 ||
3147 ctx->num_untrusted < 2)
3148 break;
3149 /* Search for a trusted issuer of a shorter chain */
3150 search |= S_DOALTERNATE;
3151 alt_untrusted = ctx->num_untrusted - 1;
3152 ss = 0;
3153 }
3154 }
3155
3156 /*
3157 * Extend chain with peer-provided certificates
3158 */
3159 if ((search & S_DOUNTRUSTED) != 0) {
3160 num = sk_X509_num(ctx->chain);
3161 if (!ossl_assert(num == ctx->num_untrusted)) {
3162 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
3163 trust = X509_TRUST_REJECTED;
3164 ctx->error = X509_V_ERR_UNSPECIFIED;
3165 search = 0;
3166 continue;
3167 }
3168 x = sk_X509_value(ctx->chain, num-1);
3169
3170 /*
3171 * Once we run out of untrusted issuers, we stop looking for more
3172 * and start looking only in the trust store if enabled.
3173 */
3174 xtmp = (ss || depth < num) ? NULL : find_issuer(ctx, sktmp, x);
3175 if (xtmp == NULL) {
3176 search &= ~S_DOUNTRUSTED;
3177 if (may_trusted)
3178 search |= S_DOTRUSTED;
3179 continue;
3180 }
3181
3182 /* Drop this issuer from future consideration */
3183 (void) sk_X509_delete_ptr(sktmp, xtmp);
3184
3185 if (!sk_X509_push(ctx->chain, xtmp)) {
3186 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
3187 trust = X509_TRUST_REJECTED;
3188 ctx->error = X509_V_ERR_OUT_OF_MEM;
3189 search = 0;
3190 continue;
3191 }
3192
3193 X509_up_ref(x = xtmp);
3194 ++ctx->num_untrusted;
3195 ss = cert_self_signed(xtmp);
3196
3197 /*
3198 * Check for DANE-TA trust of the topmost untrusted certificate.
3199 */
3200 switch (trust = check_dane_issuer(ctx, ctx->num_untrusted - 1)) {
3201 case X509_TRUST_TRUSTED:
3202 case X509_TRUST_REJECTED:
3203 search = 0;
3204 continue;
3205 }
3206 }
3207 }
3208 sk_X509_free(sktmp);
3209
3210 /*
3211 * Last chance to make a trusted chain, either bare DANE-TA public-key
3212 * signers, or else direct leaf PKIX trust.
3213 */
3214 num = sk_X509_num(ctx->chain);
3215 if (num <= depth) {
3216 if (trust == X509_TRUST_UNTRUSTED && DANETLS_HAS_DANE_TA(dane))
3217 trust = check_dane_pkeys(ctx);
3218 if (trust == X509_TRUST_UNTRUSTED && num == ctx->num_untrusted)
3219 trust = check_trust(ctx, num);
3220 }
3221
3222 switch (trust) {
3223 case X509_TRUST_TRUSTED:
3224 return 1;
3225 case X509_TRUST_REJECTED:
3226 /* Callback already issued */
3227 return 0;
3228 case X509_TRUST_UNTRUSTED:
3229 default:
3230 num = sk_X509_num(ctx->chain);
3231 if (num > depth)
3232 return verify_cb_cert(ctx, NULL, num-1,
3233 X509_V_ERR_CERT_CHAIN_TOO_LONG);
3234 if (DANETLS_ENABLED(dane) &&
3235 (!DANETLS_HAS_PKIX(dane) || dane->pdpth >= 0))
3236 return verify_cb_cert(ctx, NULL, num-1, X509_V_ERR_DANE_NO_MATCH);
3237 if (ss && sk_X509_num(ctx->chain) == 1)
3238 return verify_cb_cert(ctx, NULL, num-1,
3239 X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT);
3240 if (ss)
3241 return verify_cb_cert(ctx, NULL, num-1,
3242 X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN);
3243 if (ctx->num_untrusted < num)
3244 return verify_cb_cert(ctx, NULL, num-1,
3245 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT);
3246 return verify_cb_cert(ctx, NULL, num-1,
3247 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY);
3248 }
3249}
3250
3251static const int minbits_table[] = { 80, 112, 128, 192, 256 };
3252static const int NUM_AUTH_LEVELS = OSSL_NELEM(minbits_table);
3253
3254/*
3255 * Check whether the public key of ``cert`` meets the security level of
3256 * ``ctx``.
3257 *
3258 * Returns 1 on success, 0 otherwise.
3259 */
3260static int check_key_level(X509_STORE_CTX *ctx, X509 *cert)
3261{
3262 EVP_PKEY *pkey = X509_get0_pubkey(cert);
3263 int level = ctx->param->auth_level;
3264
3265 /*
3266 * At security level zero, return without checking for a supported public
3267 * key type. Some engines support key types not understood outside the
3268 * engine, and we only need to understand the key when enforcing a security
3269 * floor.
3270 */
3271 if (level <= 0)
3272 return 1;
3273
3274 /* Unsupported or malformed keys are not secure */
3275 if (pkey == NULL)
3276 return 0;
3277
3278 if (level > NUM_AUTH_LEVELS)
3279 level = NUM_AUTH_LEVELS;
3280
3281 return EVP_PKEY_security_bits(pkey) >= minbits_table[level - 1];
3282}
3283
3284/*
3285 * Check whether the signature digest algorithm of ``cert`` meets the security
3286 * level of ``ctx``. Should not be checked for trust anchors (whether
3287 * self-signed or otherwise).
3288 *
3289 * Returns 1 on success, 0 otherwise.
3290 */
3291static int check_sig_level(X509_STORE_CTX *ctx, X509 *cert)
3292{
3293 int secbits = -1;
3294 int level = ctx->param->auth_level;
3295
3296 if (level <= 0)
3297 return 1;
3298 if (level > NUM_AUTH_LEVELS)
3299 level = NUM_AUTH_LEVELS;
3300
3301 if (!X509_get_signature_info(cert, NULL, NULL, &secbits, NULL))
3302 return 0;
3303
3304 return secbits >= minbits_table[level - 1];
3305}
3306