1 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
4 * This package is an SSL implementation written
5 * by Eric Young (eay@cryptsoft.com).
6 * The implementation was written so as to conform with Netscapes SSL.
8 * This library is free for commercial and non-commercial use as long as
9 * the following conditions are aheared to. The following conditions
10 * apply to all code found in this distribution, be it the RC4, RSA,
11 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
12 * included with this distribution is covered by the same copyright terms
13 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15 * Copyright remains Eric Young's, and as such any Copyright notices in
16 * the code are not to be removed.
17 * If this package is used in a product, Eric Young should be given attribution
18 * as the author of the parts of the library used.
19 * This can be in the form of a textual message at program startup or
20 * in documentation (online or textual) provided with the package.
22 * Redistribution and use in source and binary forms, with or without
23 * modification, are permitted provided that the following conditions
25 * 1. Redistributions of source code must retain the copyright
26 * notice, this list of conditions and the following disclaimer.
27 * 2. Redistributions in binary form must reproduce the above copyright
28 * notice, this list of conditions and the following disclaimer in the
29 * documentation and/or other materials provided with the distribution.
30 * 3. All advertising materials mentioning features or use of this software
31 * must display the following acknowledgement:
32 * "This product includes cryptographic software written by
33 * Eric Young (eay@cryptsoft.com)"
34 * The word 'cryptographic' can be left out if the rouines from the library
35 * being used are not cryptographic related :-).
36 * 4. If you include any Windows specific code (or a derivative thereof) from
37 * the apps directory (application code) you must include an acknowledgement:
38 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
41 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
43 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
44 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
45 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
46 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
48 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
49 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
52 * The licence and distribution terms for any publically available version or
53 * derivative of this code cannot be changed. i.e. this code cannot simply be
54 * copied and put under another distribution licence
55 * [including the GNU Public Licence.]
63 #include "internal/cryptlib.h"
64 #include <openssl/crypto.h>
65 #include <openssl/lhash.h>
66 #include <openssl/buffer.h>
67 #include <openssl/evp.h>
68 #include <openssl/asn1.h>
69 #include <openssl/x509.h>
70 #include <openssl/x509v3.h>
71 #include <openssl/objects.h>
72 #include <internal/dane.h>
73 #include <internal/x509_int.h>
76 /* CRL score values */
78 /* No unhandled critical extensions */
80 #define CRL_SCORE_NOCRITICAL 0x100
82 /* certificate is within CRL scope */
84 #define CRL_SCORE_SCOPE 0x080
88 #define CRL_SCORE_TIME 0x040
90 /* Issuer name matches certificate */
92 #define CRL_SCORE_ISSUER_NAME 0x020
94 /* If this score or above CRL is probably valid */
96 #define CRL_SCORE_VALID (CRL_SCORE_NOCRITICAL|CRL_SCORE_TIME|CRL_SCORE_SCOPE)
98 /* CRL issuer is certificate issuer */
100 #define CRL_SCORE_ISSUER_CERT 0x018
102 /* CRL issuer is on certificate path */
104 #define CRL_SCORE_SAME_PATH 0x008
106 /* CRL issuer matches CRL AKID */
108 #define CRL_SCORE_AKID 0x004
110 /* Have a delta CRL with valid times */
112 #define CRL_SCORE_TIME_DELTA 0x002
114 static int build_chain(X509_STORE_CTX *ctx);
115 static int verify_chain(X509_STORE_CTX *ctx);
116 static int dane_verify(X509_STORE_CTX *ctx);
117 static int null_callback(int ok, X509_STORE_CTX *e);
118 static int check_issued(X509_STORE_CTX *ctx, X509 *x, X509 *issuer);
119 static X509 *find_issuer(X509_STORE_CTX *ctx, STACK_OF(X509) *sk, X509 *x);
120 static int check_chain_extensions(X509_STORE_CTX *ctx);
121 static int check_name_constraints(X509_STORE_CTX *ctx);
122 static int check_id(X509_STORE_CTX *ctx);
123 static int check_trust(X509_STORE_CTX *ctx, int num_untrusted);
124 static int check_revocation(X509_STORE_CTX *ctx);
125 static int check_cert(X509_STORE_CTX *ctx);
126 static int check_policy(X509_STORE_CTX *ctx);
127 static int get_issuer_sk(X509 **issuer, X509_STORE_CTX *ctx, X509 *x);
128 static int check_dane_issuer(X509_STORE_CTX *ctx, int depth);
130 static int get_crl_score(X509_STORE_CTX *ctx, X509 **pissuer,
131 unsigned int *preasons, X509_CRL *crl, X509 *x);
132 static int get_crl_delta(X509_STORE_CTX *ctx,
133 X509_CRL **pcrl, X509_CRL **pdcrl, X509 *x);
134 static void get_delta_sk(X509_STORE_CTX *ctx, X509_CRL **dcrl,
135 int *pcrl_score, X509_CRL *base,
136 STACK_OF(X509_CRL) *crls);
137 static void crl_akid_check(X509_STORE_CTX *ctx, X509_CRL *crl, X509 **pissuer,
139 static int crl_crldp_check(X509 *x, X509_CRL *crl, int crl_score,
140 unsigned int *preasons);
141 static int check_crl_path(X509_STORE_CTX *ctx, X509 *x);
142 static int check_crl_chain(X509_STORE_CTX *ctx,
143 STACK_OF(X509) *cert_path,
144 STACK_OF(X509) *crl_path);
146 static int internal_verify(X509_STORE_CTX *ctx);
148 static int null_callback(int ok, X509_STORE_CTX *e)
153 /* Return 1 is a certificate is self signed */
154 static int cert_self_signed(X509 *x)
157 * FIXME: x509v3_cache_extensions() needs to detect more failures and not
158 * set EXFLAG_SET when that happens. Especially, if the failures are
159 * parse errors, rather than memory pressure!
161 X509_check_purpose(x, -1, 0);
162 if (x->ex_flags & EXFLAG_SS)
168 /* Given a certificate try and find an exact match in the store */
170 static X509 *lookup_cert_match(X509_STORE_CTX *ctx, X509 *x)
172 STACK_OF(X509) *certs;
175 /* Lookup all certs with matching subject name */
176 certs = ctx->lookup_certs(ctx, X509_get_subject_name(x));
179 /* Look for exact match */
180 for (i = 0; i < sk_X509_num(certs); i++) {
181 xtmp = sk_X509_value(certs, i);
182 if (!X509_cmp(xtmp, x))
185 if (i < sk_X509_num(certs))
189 sk_X509_pop_free(certs, X509_free);
193 static int verify_chain(X509_STORE_CTX *ctx)
199 * Before either returning with an error, or continuing with CRL checks,
200 * instantiate chain public key parameters.
202 if ((ok = build_chain(ctx)) == 0 ||
203 (ok = check_chain_extensions(ctx)) == 0 ||
204 (ok = check_name_constraints(ctx)) == 0 ||
205 (ok = check_id(ctx)) == 0 || 1)
206 X509_get_pubkey_parameters(NULL, ctx->chain);
207 if (ok == 0 || (ok = ctx->check_revocation(ctx)) == 0)
210 err = X509_chain_check_suiteb(&ctx->error_depth, NULL, ctx->chain,
212 if (err != X509_V_OK) {
214 ctx->current_cert = sk_X509_value(ctx->chain, ctx->error_depth);
215 if ((ok = ctx->verify_cb(0, ctx)) == 0)
219 /* Verify chain signatures and expiration times */
220 ok = (ctx->verify != NULL) ? ctx->verify(ctx) : internal_verify(ctx);
224 #ifndef OPENSSL_NO_RFC3779
225 /* RFC 3779 path validation, now that CRL check has been done */
226 if ((ok = v3_asid_validate_path(ctx)) == 0)
228 if ((ok = v3_addr_validate_path(ctx)) == 0)
232 /* If we get this far evaluate policies */
233 if (ctx->param->flags & X509_V_FLAG_POLICY_CHECK)
234 ok = ctx->check_policy(ctx);
238 int X509_verify_cert(X509_STORE_CTX *ctx)
240 struct dane_st *dane = (struct dane_st *)ctx->dane;
242 if (ctx->cert == NULL) {
243 X509err(X509_F_X509_VERIFY_CERT, X509_R_NO_CERT_SET_FOR_US_TO_VERIFY);
247 if (ctx->chain != NULL) {
249 * This X509_STORE_CTX has already been used to verify a cert. We
250 * cannot do another one.
252 X509err(X509_F_X509_VERIFY_CERT, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
257 * first we make sure the chain we are going to build is present and that
258 * the first entry is in place
260 if (((ctx->chain = sk_X509_new_null()) == NULL) ||
261 (!sk_X509_push(ctx->chain, ctx->cert))) {
262 X509err(X509_F_X509_VERIFY_CERT, ERR_R_MALLOC_FAILURE);
265 X509_up_ref(ctx->cert);
266 ctx->num_untrusted = 1;
269 * If dane->trecs is an empty stack, we'll fail, since the user enabled
270 * DANE. If none of the TLSA records were usable, and it makes sense to
271 * keep going with an unauthenticated handshake, they can handle that in
272 * the verify callback, or not set SSL_VERIFY_PEER.
274 if (DANETLS_ENABLED(dane))
275 return dane_verify(ctx);
276 return verify_chain(ctx);
280 * Given a STACK_OF(X509) find the issuer of cert (if any)
283 static X509 *find_issuer(X509_STORE_CTX *ctx, STACK_OF(X509) *sk, X509 *x)
286 X509 *issuer, *rv = NULL;;
287 for (i = 0; i < sk_X509_num(sk); i++) {
288 issuer = sk_X509_value(sk, i);
289 if (ctx->check_issued(ctx, x, issuer)) {
291 if (x509_check_cert_time(ctx, rv, 1))
298 /* Given a possible certificate and issuer check them */
300 static int check_issued(X509_STORE_CTX *ctx, X509 *x, X509 *issuer)
304 return cert_self_signed(x);
305 ret = X509_check_issued(issuer, x);
306 if (ret == X509_V_OK) {
309 /* Special case: single self signed certificate */
310 if (cert_self_signed(x) && sk_X509_num(ctx->chain) == 1)
312 for (i = 0; i < sk_X509_num(ctx->chain); i++) {
313 ch = sk_X509_value(ctx->chain, i);
314 if (ch == issuer || !X509_cmp(ch, issuer)) {
315 ret = X509_V_ERR_PATH_LOOP;
321 if (ret == X509_V_OK)
323 /* If we haven't asked for issuer errors don't set ctx */
324 if (!(ctx->param->flags & X509_V_FLAG_CB_ISSUER_CHECK))
328 ctx->current_cert = x;
329 ctx->current_issuer = issuer;
330 return ctx->verify_cb(0, ctx);
333 /* Alternative lookup method: look from a STACK stored in other_ctx */
335 static int get_issuer_sk(X509 **issuer, X509_STORE_CTX *ctx, X509 *x)
337 *issuer = find_issuer(ctx, ctx->other_ctx, x);
339 X509_up_ref(*issuer);
345 static STACK_OF(X509) *lookup_certs_sk(X509_STORE_CTX *ctx, X509_NAME *nm)
347 STACK_OF(X509) *sk = NULL;
350 for (i = 0; i < sk_X509_num(ctx->other_ctx); i++) {
351 x = sk_X509_value(ctx->other_ctx, i);
352 if (X509_NAME_cmp(nm, X509_get_subject_name(x)) == 0) {
354 sk = sk_X509_new_null();
355 if (sk == NULL || sk_X509_push(sk, x) == 0) {
356 sk_X509_pop_free(sk, X509_free);
366 * Check EE or CA certificate purpose. For trusted certificates explicit local
367 * auxiliary trust can be used to override EKU-restrictions.
369 static int check_purpose(X509_STORE_CTX *ctx, X509 *x, int purpose, int depth,
372 int tr_ok = X509_TRUST_UNTRUSTED;
375 * For trusted certificates we want to see whether any auxiliary trust
376 * settings trump the purpose constraints.
378 * This is complicated by the fact that the trust ordinals in
379 * ctx->param->trust are entirely independent of the purpose ordinals in
380 * ctx->param->purpose!
382 * What connects them is their mutual initialization via calls from
383 * X509_STORE_CTX_set_default() into X509_VERIFY_PARAM_lookup() which sets
384 * related values of both param->trust and param->purpose. It is however
385 * typically possible to infer associated trust values from a purpose value
386 * via the X509_PURPOSE API.
388 * Therefore, we can only check for trust overrides when the purpose we're
389 * checking is the same as ctx->param->purpose and ctx->param->trust is
392 if (depth >= ctx->num_untrusted && purpose == ctx->param->purpose)
393 tr_ok = X509_check_trust(x, ctx->param->trust, X509_TRUST_NO_SS_COMPAT);
396 case X509_TRUST_TRUSTED:
398 case X509_TRUST_REJECTED:
401 switch (X509_check_purpose(x, purpose, must_be_ca > 0)) {
407 if ((ctx->param->flags & X509_V_FLAG_X509_STRICT) == 0)
413 ctx->error = X509_V_ERR_INVALID_PURPOSE;
414 ctx->error_depth = depth;
415 ctx->current_cert = x;
416 return ctx->verify_cb(0, ctx);
420 * Check a certificate chains extensions for consistency with the supplied
424 static int check_chain_extensions(X509_STORE_CTX *ctx)
426 int i, must_be_ca, plen = 0;
428 int proxy_path_length = 0;
430 int allow_proxy_certs;
431 int num = sk_X509_num(ctx->chain);
434 * must_be_ca can have 1 of 3 values:
435 * -1: we accept both CA and non-CA certificates, to allow direct
436 * use of self-signed certificates (which are marked as CA).
437 * 0: we only accept non-CA certificates. This is currently not
438 * used, but the possibility is present for future extensions.
439 * 1: we only accept CA certificates. This is currently used for
440 * all certificates in the chain except the leaf certificate.
444 /* CRL path validation */
446 allow_proxy_certs = 0;
447 purpose = X509_PURPOSE_CRL_SIGN;
450 ! !(ctx->param->flags & X509_V_FLAG_ALLOW_PROXY_CERTS);
452 * A hack to keep people who don't want to modify their software
455 if (getenv("OPENSSL_ALLOW_PROXY_CERTS"))
456 allow_proxy_certs = 1;
457 purpose = ctx->param->purpose;
460 for (i = 0; i < num; i++) {
462 x = sk_X509_value(ctx->chain, i);
463 if (!(ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL)
464 && (x->ex_flags & EXFLAG_CRITICAL)) {
465 ctx->error = X509_V_ERR_UNHANDLED_CRITICAL_EXTENSION;
466 ctx->error_depth = i;
467 ctx->current_cert = x;
468 if (!ctx->verify_cb(0, ctx))
471 if (!allow_proxy_certs && (x->ex_flags & EXFLAG_PROXY)) {
472 ctx->error = X509_V_ERR_PROXY_CERTIFICATES_NOT_ALLOWED;
473 ctx->error_depth = i;
474 ctx->current_cert = x;
475 if (!ctx->verify_cb(0, ctx))
478 ret = X509_check_ca(x);
479 switch (must_be_ca) {
481 if ((ctx->param->flags & X509_V_FLAG_X509_STRICT)
482 && (ret != 1) && (ret != 0)) {
484 ctx->error = X509_V_ERR_INVALID_CA;
491 ctx->error = X509_V_ERR_INVALID_NON_CA;
497 || ((ctx->param->flags & X509_V_FLAG_X509_STRICT)
500 ctx->error = X509_V_ERR_INVALID_CA;
506 ctx->error_depth = i;
507 ctx->current_cert = x;
508 if (!ctx->verify_cb(0, ctx))
512 if (!check_purpose(ctx, x, purpose, i, must_be_ca))
515 /* Check pathlen if not self issued */
516 if ((i > 1) && !(x->ex_flags & EXFLAG_SI)
517 && (x->ex_pathlen != -1)
518 && (plen > (x->ex_pathlen + proxy_path_length + 1))) {
519 ctx->error = X509_V_ERR_PATH_LENGTH_EXCEEDED;
520 ctx->error_depth = i;
521 ctx->current_cert = x;
522 if (!ctx->verify_cb(0, ctx))
525 /* Increment path length if not self issued */
526 if (!(x->ex_flags & EXFLAG_SI))
529 * If this certificate is a proxy certificate, the next certificate
530 * must be another proxy certificate or a EE certificate. If not,
531 * the next certificate must be a CA certificate.
533 if (x->ex_flags & EXFLAG_PROXY) {
534 if (x->ex_pcpathlen != -1 && i > x->ex_pcpathlen) {
535 ctx->error = X509_V_ERR_PROXY_PATH_LENGTH_EXCEEDED;
536 ctx->error_depth = i;
537 ctx->current_cert = x;
538 if (!ctx->verify_cb(0, ctx))
549 static int check_name_constraints(X509_STORE_CTX *ctx)
553 /* Check name constraints for all certificates */
554 for (i = sk_X509_num(ctx->chain) - 1; i >= 0; i--) {
555 x = sk_X509_value(ctx->chain, i);
556 /* Ignore self issued certs unless last in chain */
557 if (i && (x->ex_flags & EXFLAG_SI))
560 * Check against constraints for all certificates higher in chain
561 * including trust anchor. Trust anchor not strictly speaking needed
562 * but if it includes constraints it is to be assumed it expects them
565 for (j = sk_X509_num(ctx->chain) - 1; j > i; j--) {
566 NAME_CONSTRAINTS *nc = sk_X509_value(ctx->chain, j)->nc;
568 rv = NAME_CONSTRAINTS_check(x, nc);
569 if (rv != X509_V_OK) {
571 ctx->error_depth = i;
572 ctx->current_cert = x;
573 if (!ctx->verify_cb(0, ctx))
582 static int check_id_error(X509_STORE_CTX *ctx, int errcode)
584 ctx->error = errcode;
585 ctx->current_cert = ctx->cert;
586 ctx->error_depth = 0;
587 return ctx->verify_cb(0, ctx);
590 static int check_hosts(X509 *x, X509_VERIFY_PARAM *vpm)
593 int n = sk_OPENSSL_STRING_num(vpm->hosts);
596 if (vpm->peername != NULL) {
597 OPENSSL_free(vpm->peername);
598 vpm->peername = NULL;
600 for (i = 0; i < n; ++i) {
601 name = sk_OPENSSL_STRING_value(vpm->hosts, i);
602 if (X509_check_host(x, name, 0, vpm->hostflags, &vpm->peername) > 0)
608 static int check_id(X509_STORE_CTX *ctx)
610 X509_VERIFY_PARAM *vpm = ctx->param;
612 if (vpm->hosts && check_hosts(x, vpm) <= 0) {
613 if (!check_id_error(ctx, X509_V_ERR_HOSTNAME_MISMATCH))
616 if (vpm->email && X509_check_email(x, vpm->email, vpm->emaillen, 0) <= 0) {
617 if (!check_id_error(ctx, X509_V_ERR_EMAIL_MISMATCH))
620 if (vpm->ip && X509_check_ip(x, vpm->ip, vpm->iplen, 0) <= 0) {
621 if (!check_id_error(ctx, X509_V_ERR_IP_ADDRESS_MISMATCH))
627 static int check_trust(X509_STORE_CTX *ctx, int num_untrusted)
632 struct dane_st *dane = (struct dane_st *)ctx->dane;
633 int num = sk_X509_num(ctx->chain);
637 * Check for a DANE issuer at depth 1 or greater, if it is a DANE-TA(2)
638 * match, we're done, otherwise we'll merely record the match depth.
640 if (DANETLS_HAS_TA(dane) && num_untrusted > 0 && num_untrusted < num) {
641 switch (trust = check_dane_issuer(ctx, num_untrusted)) {
642 case X509_TRUST_TRUSTED:
643 case X509_TRUST_REJECTED:
649 * Check trusted certificates in chain at depth num_untrusted and up.
650 * Note, that depths 0..num_untrusted-1 may also contain trusted
651 * certificates, but the caller is expected to have already checked those,
652 * and wants to incrementally check just any added since.
654 for (i = num_untrusted; i < num; i++) {
655 x = sk_X509_value(ctx->chain, i);
656 trust = X509_check_trust(x, ctx->param->trust, 0);
657 /* If explicitly trusted return trusted */
658 if (trust == X509_TRUST_TRUSTED)
660 if (trust == X509_TRUST_REJECTED)
665 * If we are looking at a trusted certificate, and accept partial chains,
666 * the chain is PKIX trusted.
668 if (num_untrusted < num) {
669 if (ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN)
671 return X509_TRUST_UNTRUSTED;
674 if (num_untrusted == num && ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) {
676 * Last-resort call with no new trusted certificates, check the leaf
677 * for a direct trust store match.
680 x = sk_X509_value(ctx->chain, i);
681 mx = lookup_cert_match(ctx, x);
683 return X509_TRUST_UNTRUSTED;
686 * Check explicit auxiliary trust/reject settings. If none are set,
687 * we'll accept X509_TRUST_UNTRUSTED when not self-signed.
689 trust = X509_check_trust(mx, ctx->param->trust, 0);
690 if (trust == X509_TRUST_REJECTED) {
695 /* Replace leaf with trusted match */
696 (void) sk_X509_set(ctx->chain, 0, mx);
698 ctx->num_untrusted = 0;
703 * If no trusted certs in chain at all return untrusted and allow
704 * standard (no issuer cert) etc errors to be indicated.
706 return X509_TRUST_UNTRUSTED;
709 ctx->error_depth = i;
710 ctx->current_cert = x;
711 ctx->error = X509_V_ERR_CERT_REJECTED;
712 ok = ctx->verify_cb(0, ctx);
714 return X509_TRUST_REJECTED;
715 return X509_TRUST_UNTRUSTED;
718 if (!DANETLS_ENABLED(dane))
719 return X509_TRUST_TRUSTED;
721 dane->pdpth = num_untrusted;
722 /* With DANE, PKIX alone is not trusted until we have both */
723 if (dane->mdpth >= 0)
724 return X509_TRUST_TRUSTED;
725 return X509_TRUST_UNTRUSTED;
728 static int check_revocation(X509_STORE_CTX *ctx)
730 int i = 0, last = 0, ok = 0;
731 if (!(ctx->param->flags & X509_V_FLAG_CRL_CHECK))
733 if (ctx->param->flags & X509_V_FLAG_CRL_CHECK_ALL)
734 last = sk_X509_num(ctx->chain) - 1;
736 /* If checking CRL paths this isn't the EE certificate */
741 for (i = 0; i <= last; i++) {
742 ctx->error_depth = i;
743 ok = check_cert(ctx);
750 static int check_cert(X509_STORE_CTX *ctx)
752 X509_CRL *crl = NULL, *dcrl = NULL;
754 int ok = 0, cnum = 0;
755 unsigned int last_reasons = 0;
756 cnum = ctx->error_depth;
757 x = sk_X509_value(ctx->chain, cnum);
758 ctx->current_cert = x;
759 ctx->current_issuer = NULL;
760 ctx->current_crl_score = 0;
761 ctx->current_reasons = 0;
762 while (ctx->current_reasons != CRLDP_ALL_REASONS) {
763 last_reasons = ctx->current_reasons;
764 /* Try to retrieve relevant CRL */
766 ok = ctx->get_crl(ctx, &crl, x);
768 ok = get_crl_delta(ctx, &crl, &dcrl, x);
770 * If error looking up CRL, nothing we can do except notify callback
773 ctx->error = X509_V_ERR_UNABLE_TO_GET_CRL;
774 ok = ctx->verify_cb(0, ctx);
777 ctx->current_crl = crl;
778 ok = ctx->check_crl(ctx, crl);
783 ok = ctx->check_crl(ctx, dcrl);
786 ok = ctx->cert_crl(ctx, dcrl, x);
792 /* Don't look in full CRL if delta reason is removefromCRL */
794 ok = ctx->cert_crl(ctx, crl, x);
804 * If reasons not updated we wont get anywhere by another iteration,
807 if (last_reasons == ctx->current_reasons) {
808 ctx->error = X509_V_ERR_UNABLE_TO_GET_CRL;
809 ok = ctx->verify_cb(0, ctx);
817 ctx->current_crl = NULL;
822 /* Check CRL times against values in X509_STORE_CTX */
824 static int check_crl_time(X509_STORE_CTX *ctx, X509_CRL *crl, int notify)
829 ctx->current_crl = crl;
830 if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME)
831 ptime = &ctx->param->check_time;
832 else if (ctx->param->flags & X509_V_FLAG_NO_CHECK_TIME)
837 i = X509_cmp_time(X509_CRL_get_lastUpdate(crl), ptime);
841 ctx->error = X509_V_ERR_ERROR_IN_CRL_LAST_UPDATE_FIELD;
842 if (!ctx->verify_cb(0, ctx))
849 ctx->error = X509_V_ERR_CRL_NOT_YET_VALID;
850 if (!ctx->verify_cb(0, ctx))
854 if (X509_CRL_get_nextUpdate(crl)) {
855 i = X509_cmp_time(X509_CRL_get_nextUpdate(crl), ptime);
860 ctx->error = X509_V_ERR_ERROR_IN_CRL_NEXT_UPDATE_FIELD;
861 if (!ctx->verify_cb(0, ctx))
864 /* Ignore expiry of base CRL is delta is valid */
865 if ((i < 0) && !(ctx->current_crl_score & CRL_SCORE_TIME_DELTA)) {
868 ctx->error = X509_V_ERR_CRL_HAS_EXPIRED;
869 if (!ctx->verify_cb(0, ctx))
875 ctx->current_crl = NULL;
880 static int get_crl_sk(X509_STORE_CTX *ctx, X509_CRL **pcrl, X509_CRL **pdcrl,
881 X509 **pissuer, int *pscore, unsigned int *preasons,
882 STACK_OF(X509_CRL) *crls)
884 int i, crl_score, best_score = *pscore;
885 unsigned int reasons, best_reasons = 0;
886 X509 *x = ctx->current_cert;
887 X509_CRL *crl, *best_crl = NULL;
888 X509 *crl_issuer = NULL, *best_crl_issuer = NULL;
890 for (i = 0; i < sk_X509_CRL_num(crls); i++) {
891 crl = sk_X509_CRL_value(crls, i);
893 crl_score = get_crl_score(ctx, &crl_issuer, &reasons, crl, x);
895 if (crl_score > best_score) {
897 best_crl_issuer = crl_issuer;
898 best_score = crl_score;
899 best_reasons = reasons;
904 X509_CRL_free(*pcrl);
906 *pissuer = best_crl_issuer;
907 *pscore = best_score;
908 *preasons = best_reasons;
909 X509_CRL_up_ref(best_crl);
910 X509_CRL_free(*pdcrl);
912 get_delta_sk(ctx, pdcrl, pscore, best_crl, crls);
915 if (best_score >= CRL_SCORE_VALID)
922 * Compare two CRL extensions for delta checking purposes. They should be
923 * both present or both absent. If both present all fields must be identical.
926 static int crl_extension_match(X509_CRL *a, X509_CRL *b, int nid)
928 ASN1_OCTET_STRING *exta, *extb;
930 i = X509_CRL_get_ext_by_NID(a, nid, -1);
932 /* Can't have multiple occurrences */
933 if (X509_CRL_get_ext_by_NID(a, nid, i) != -1)
935 exta = X509_EXTENSION_get_data(X509_CRL_get_ext(a, i));
939 i = X509_CRL_get_ext_by_NID(b, nid, -1);
943 if (X509_CRL_get_ext_by_NID(b, nid, i) != -1)
945 extb = X509_EXTENSION_get_data(X509_CRL_get_ext(b, i));
955 if (ASN1_OCTET_STRING_cmp(exta, extb))
961 /* See if a base and delta are compatible */
963 static int check_delta_base(X509_CRL *delta, X509_CRL *base)
965 /* Delta CRL must be a delta */
966 if (!delta->base_crl_number)
968 /* Base must have a CRL number */
969 if (!base->crl_number)
971 /* Issuer names must match */
972 if (X509_NAME_cmp(X509_CRL_get_issuer(base), X509_CRL_get_issuer(delta)))
974 /* AKID and IDP must match */
975 if (!crl_extension_match(delta, base, NID_authority_key_identifier))
977 if (!crl_extension_match(delta, base, NID_issuing_distribution_point))
979 /* Delta CRL base number must not exceed Full CRL number. */
980 if (ASN1_INTEGER_cmp(delta->base_crl_number, base->crl_number) > 0)
982 /* Delta CRL number must exceed full CRL number */
983 if (ASN1_INTEGER_cmp(delta->crl_number, base->crl_number) > 0)
989 * For a given base CRL find a delta... maybe extend to delta scoring or
990 * retrieve a chain of deltas...
993 static void get_delta_sk(X509_STORE_CTX *ctx, X509_CRL **dcrl, int *pscore,
994 X509_CRL *base, STACK_OF(X509_CRL) *crls)
998 if (!(ctx->param->flags & X509_V_FLAG_USE_DELTAS))
1000 if (!((ctx->current_cert->ex_flags | base->flags) & EXFLAG_FRESHEST))
1002 for (i = 0; i < sk_X509_CRL_num(crls); i++) {
1003 delta = sk_X509_CRL_value(crls, i);
1004 if (check_delta_base(delta, base)) {
1005 if (check_crl_time(ctx, delta, 0))
1006 *pscore |= CRL_SCORE_TIME_DELTA;
1007 X509_CRL_up_ref(delta);
1016 * For a given CRL return how suitable it is for the supplied certificate
1017 * 'x'. The return value is a mask of several criteria. If the issuer is not
1018 * the certificate issuer this is returned in *pissuer. The reasons mask is
1019 * also used to determine if the CRL is suitable: if no new reasons the CRL
1020 * is rejected, otherwise reasons is updated.
1023 static int get_crl_score(X509_STORE_CTX *ctx, X509 **pissuer,
1024 unsigned int *preasons, X509_CRL *crl, X509 *x)
1028 unsigned int tmp_reasons = *preasons, crl_reasons;
1030 /* First see if we can reject CRL straight away */
1032 /* Invalid IDP cannot be processed */
1033 if (crl->idp_flags & IDP_INVALID)
1035 /* Reason codes or indirect CRLs need extended CRL support */
1036 if (!(ctx->param->flags & X509_V_FLAG_EXTENDED_CRL_SUPPORT)) {
1037 if (crl->idp_flags & (IDP_INDIRECT | IDP_REASONS))
1039 } else if (crl->idp_flags & IDP_REASONS) {
1040 /* If no new reasons reject */
1041 if (!(crl->idp_reasons & ~tmp_reasons))
1044 /* Don't process deltas at this stage */
1045 else if (crl->base_crl_number)
1047 /* If issuer name doesn't match certificate need indirect CRL */
1048 if (X509_NAME_cmp(X509_get_issuer_name(x), X509_CRL_get_issuer(crl))) {
1049 if (!(crl->idp_flags & IDP_INDIRECT))
1052 crl_score |= CRL_SCORE_ISSUER_NAME;
1054 if (!(crl->flags & EXFLAG_CRITICAL))
1055 crl_score |= CRL_SCORE_NOCRITICAL;
1058 if (check_crl_time(ctx, crl, 0))
1059 crl_score |= CRL_SCORE_TIME;
1061 /* Check authority key ID and locate certificate issuer */
1062 crl_akid_check(ctx, crl, pissuer, &crl_score);
1064 /* If we can't locate certificate issuer at this point forget it */
1066 if (!(crl_score & CRL_SCORE_AKID))
1069 /* Check cert for matching CRL distribution points */
1071 if (crl_crldp_check(x, crl, crl_score, &crl_reasons)) {
1072 /* If no new reasons reject */
1073 if (!(crl_reasons & ~tmp_reasons))
1075 tmp_reasons |= crl_reasons;
1076 crl_score |= CRL_SCORE_SCOPE;
1079 *preasons = tmp_reasons;
1085 static void crl_akid_check(X509_STORE_CTX *ctx, X509_CRL *crl,
1086 X509 **pissuer, int *pcrl_score)
1088 X509 *crl_issuer = NULL;
1089 X509_NAME *cnm = X509_CRL_get_issuer(crl);
1090 int cidx = ctx->error_depth;
1093 if (cidx != sk_X509_num(ctx->chain) - 1)
1096 crl_issuer = sk_X509_value(ctx->chain, cidx);
1098 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1099 if (*pcrl_score & CRL_SCORE_ISSUER_NAME) {
1100 *pcrl_score |= CRL_SCORE_AKID | CRL_SCORE_ISSUER_CERT;
1101 *pissuer = crl_issuer;
1106 for (cidx++; cidx < sk_X509_num(ctx->chain); cidx++) {
1107 crl_issuer = sk_X509_value(ctx->chain, cidx);
1108 if (X509_NAME_cmp(X509_get_subject_name(crl_issuer), cnm))
1110 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1111 *pcrl_score |= CRL_SCORE_AKID | CRL_SCORE_SAME_PATH;
1112 *pissuer = crl_issuer;
1117 /* Anything else needs extended CRL support */
1119 if (!(ctx->param->flags & X509_V_FLAG_EXTENDED_CRL_SUPPORT))
1123 * Otherwise the CRL issuer is not on the path. Look for it in the set of
1124 * untrusted certificates.
1126 for (i = 0; i < sk_X509_num(ctx->untrusted); i++) {
1127 crl_issuer = sk_X509_value(ctx->untrusted, i);
1128 if (X509_NAME_cmp(X509_get_subject_name(crl_issuer), cnm))
1130 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1131 *pissuer = crl_issuer;
1132 *pcrl_score |= CRL_SCORE_AKID;
1139 * Check the path of a CRL issuer certificate. This creates a new
1140 * X509_STORE_CTX and populates it with most of the parameters from the
1141 * parent. This could be optimised somewhat since a lot of path checking will
1142 * be duplicated by the parent, but this will rarely be used in practice.
1145 static int check_crl_path(X509_STORE_CTX *ctx, X509 *x)
1147 X509_STORE_CTX crl_ctx;
1149 /* Don't allow recursive CRL path validation */
1152 if (!X509_STORE_CTX_init(&crl_ctx, ctx->ctx, x, ctx->untrusted))
1155 crl_ctx.crls = ctx->crls;
1156 /* Copy verify params across */
1157 X509_STORE_CTX_set0_param(&crl_ctx, ctx->param);
1159 crl_ctx.parent = ctx;
1160 crl_ctx.verify_cb = ctx->verify_cb;
1162 /* Verify CRL issuer */
1163 ret = X509_verify_cert(&crl_ctx);
1168 /* Check chain is acceptable */
1170 ret = check_crl_chain(ctx, ctx->chain, crl_ctx.chain);
1172 X509_STORE_CTX_cleanup(&crl_ctx);
1177 * RFC3280 says nothing about the relationship between CRL path and
1178 * certificate path, which could lead to situations where a certificate could
1179 * be revoked or validated by a CA not authorised to do so. RFC5280 is more
1180 * strict and states that the two paths must end in the same trust anchor,
1181 * though some discussions remain... until this is resolved we use the
1185 static int check_crl_chain(X509_STORE_CTX *ctx,
1186 STACK_OF(X509) *cert_path,
1187 STACK_OF(X509) *crl_path)
1189 X509 *cert_ta, *crl_ta;
1190 cert_ta = sk_X509_value(cert_path, sk_X509_num(cert_path) - 1);
1191 crl_ta = sk_X509_value(crl_path, sk_X509_num(crl_path) - 1);
1192 if (!X509_cmp(cert_ta, crl_ta))
1198 * Check for match between two dist point names: three separate cases.
1199 * 1. Both are relative names and compare X509_NAME types.
1200 * 2. One full, one relative. Compare X509_NAME to GENERAL_NAMES.
1201 * 3. Both are full names and compare two GENERAL_NAMES.
1202 * 4. One is NULL: automatic match.
1205 static int idp_check_dp(DIST_POINT_NAME *a, DIST_POINT_NAME *b)
1207 X509_NAME *nm = NULL;
1208 GENERAL_NAMES *gens = NULL;
1209 GENERAL_NAME *gena, *genb;
1216 /* Case 1: two X509_NAME */
1220 if (!X509_NAME_cmp(a->dpname, b->dpname))
1225 /* Case 2: set name and GENERAL_NAMES appropriately */
1227 gens = b->name.fullname;
1228 } else if (b->type == 1) {
1231 /* Case 2: set name and GENERAL_NAMES appropriately */
1232 gens = a->name.fullname;
1236 /* Handle case 2 with one GENERAL_NAMES and one X509_NAME */
1238 for (i = 0; i < sk_GENERAL_NAME_num(gens); i++) {
1239 gena = sk_GENERAL_NAME_value(gens, i);
1240 if (gena->type != GEN_DIRNAME)
1242 if (!X509_NAME_cmp(nm, gena->d.directoryName))
1248 /* Else case 3: two GENERAL_NAMES */
1250 for (i = 0; i < sk_GENERAL_NAME_num(a->name.fullname); i++) {
1251 gena = sk_GENERAL_NAME_value(a->name.fullname, i);
1252 for (j = 0; j < sk_GENERAL_NAME_num(b->name.fullname); j++) {
1253 genb = sk_GENERAL_NAME_value(b->name.fullname, j);
1254 if (!GENERAL_NAME_cmp(gena, genb))
1263 static int crldp_check_crlissuer(DIST_POINT *dp, X509_CRL *crl, int crl_score)
1266 X509_NAME *nm = X509_CRL_get_issuer(crl);
1267 /* If no CRLissuer return is successful iff don't need a match */
1269 return ! !(crl_score & CRL_SCORE_ISSUER_NAME);
1270 for (i = 0; i < sk_GENERAL_NAME_num(dp->CRLissuer); i++) {
1271 GENERAL_NAME *gen = sk_GENERAL_NAME_value(dp->CRLissuer, i);
1272 if (gen->type != GEN_DIRNAME)
1274 if (!X509_NAME_cmp(gen->d.directoryName, nm))
1280 /* Check CRLDP and IDP */
1282 static int crl_crldp_check(X509 *x, X509_CRL *crl, int crl_score,
1283 unsigned int *preasons)
1286 if (crl->idp_flags & IDP_ONLYATTR)
1288 if (x->ex_flags & EXFLAG_CA) {
1289 if (crl->idp_flags & IDP_ONLYUSER)
1292 if (crl->idp_flags & IDP_ONLYCA)
1295 *preasons = crl->idp_reasons;
1296 for (i = 0; i < sk_DIST_POINT_num(x->crldp); i++) {
1297 DIST_POINT *dp = sk_DIST_POINT_value(x->crldp, i);
1298 if (crldp_check_crlissuer(dp, crl, crl_score)) {
1299 if (!crl->idp || idp_check_dp(dp->distpoint, crl->idp->distpoint)) {
1300 *preasons &= dp->dp_reasons;
1305 if ((!crl->idp || !crl->idp->distpoint)
1306 && (crl_score & CRL_SCORE_ISSUER_NAME))
1312 * Retrieve CRL corresponding to current certificate. If deltas enabled try
1313 * to find a delta CRL too
1316 static int get_crl_delta(X509_STORE_CTX *ctx,
1317 X509_CRL **pcrl, X509_CRL **pdcrl, X509 *x)
1320 X509 *issuer = NULL;
1322 unsigned int reasons;
1323 X509_CRL *crl = NULL, *dcrl = NULL;
1324 STACK_OF(X509_CRL) *skcrl;
1325 X509_NAME *nm = X509_get_issuer_name(x);
1326 reasons = ctx->current_reasons;
1327 ok = get_crl_sk(ctx, &crl, &dcrl,
1328 &issuer, &crl_score, &reasons, ctx->crls);
1333 /* Lookup CRLs from store */
1335 skcrl = ctx->lookup_crls(ctx, nm);
1337 /* If no CRLs found and a near match from get_crl_sk use that */
1341 get_crl_sk(ctx, &crl, &dcrl, &issuer, &crl_score, &reasons, skcrl);
1343 sk_X509_CRL_pop_free(skcrl, X509_CRL_free);
1347 /* If we got any kind of CRL use it and return success */
1349 ctx->current_issuer = issuer;
1350 ctx->current_crl_score = crl_score;
1351 ctx->current_reasons = reasons;
1360 /* Check CRL validity */
1361 static int check_crl(X509_STORE_CTX *ctx, X509_CRL *crl)
1363 X509 *issuer = NULL;
1364 EVP_PKEY *ikey = NULL;
1365 int ok = 0, chnum, cnum;
1366 cnum = ctx->error_depth;
1367 chnum = sk_X509_num(ctx->chain) - 1;
1368 /* if we have an alternative CRL issuer cert use that */
1369 if (ctx->current_issuer)
1370 issuer = ctx->current_issuer;
1373 * Else find CRL issuer: if not last certificate then issuer is next
1374 * certificate in chain.
1376 else if (cnum < chnum)
1377 issuer = sk_X509_value(ctx->chain, cnum + 1);
1379 issuer = sk_X509_value(ctx->chain, chnum);
1380 /* If not self signed, can't check signature */
1381 if (!ctx->check_issued(ctx, issuer, issuer)) {
1382 ctx->error = X509_V_ERR_UNABLE_TO_GET_CRL_ISSUER;
1383 ok = ctx->verify_cb(0, ctx);
1391 * Skip most tests for deltas because they have already been done
1393 if (!crl->base_crl_number) {
1394 /* Check for cRLSign bit if keyUsage present */
1395 if ((issuer->ex_flags & EXFLAG_KUSAGE) &&
1396 !(issuer->ex_kusage & KU_CRL_SIGN)) {
1397 ctx->error = X509_V_ERR_KEYUSAGE_NO_CRL_SIGN;
1398 ok = ctx->verify_cb(0, ctx);
1403 if (!(ctx->current_crl_score & CRL_SCORE_SCOPE)) {
1404 ctx->error = X509_V_ERR_DIFFERENT_CRL_SCOPE;
1405 ok = ctx->verify_cb(0, ctx);
1410 if (!(ctx->current_crl_score & CRL_SCORE_SAME_PATH)) {
1411 if (check_crl_path(ctx, ctx->current_issuer) <= 0) {
1412 ctx->error = X509_V_ERR_CRL_PATH_VALIDATION_ERROR;
1413 ok = ctx->verify_cb(0, ctx);
1419 if (crl->idp_flags & IDP_INVALID) {
1420 ctx->error = X509_V_ERR_INVALID_EXTENSION;
1421 ok = ctx->verify_cb(0, ctx);
1428 if (!(ctx->current_crl_score & CRL_SCORE_TIME)) {
1429 ok = check_crl_time(ctx, crl, 1);
1434 /* Attempt to get issuer certificate public key */
1435 ikey = X509_get0_pubkey(issuer);
1438 ctx->error = X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY;
1439 ok = ctx->verify_cb(0, ctx);
1444 rv = X509_CRL_check_suiteb(crl, ikey, ctx->param->flags);
1445 if (rv != X509_V_OK) {
1447 ok = ctx->verify_cb(0, ctx);
1451 /* Verify CRL signature */
1452 if (X509_CRL_verify(crl, ikey) <= 0) {
1453 ctx->error = X509_V_ERR_CRL_SIGNATURE_FAILURE;
1454 ok = ctx->verify_cb(0, ctx);
1467 /* Check certificate against CRL */
1468 static int cert_crl(X509_STORE_CTX *ctx, X509_CRL *crl, X509 *x)
1473 * The rules changed for this... previously if a CRL contained unhandled
1474 * critical extensions it could still be used to indicate a certificate
1475 * was revoked. This has since been changed since critical extension can
1476 * change the meaning of CRL entries.
1478 if (!(ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL)
1479 && (crl->flags & EXFLAG_CRITICAL)) {
1480 ctx->error = X509_V_ERR_UNHANDLED_CRITICAL_CRL_EXTENSION;
1481 ok = ctx->verify_cb(0, ctx);
1486 * Look for serial number of certificate in CRL If found make sure reason
1487 * is not removeFromCRL.
1489 if (X509_CRL_get0_by_cert(crl, &rev, x)) {
1490 if (rev->reason == CRL_REASON_REMOVE_FROM_CRL)
1492 ctx->error = X509_V_ERR_CERT_REVOKED;
1493 ok = ctx->verify_cb(0, ctx);
1501 static int check_policy(X509_STORE_CTX *ctx)
1506 ret = X509_policy_check(&ctx->tree, &ctx->explicit_policy, ctx->chain,
1507 ctx->param->policies, ctx->param->flags);
1509 X509err(X509_F_CHECK_POLICY, ERR_R_MALLOC_FAILURE);
1512 /* Invalid or inconsistent extensions */
1515 * Locate certificates with bad extensions and notify callback.
1519 for (i = 1; i < sk_X509_num(ctx->chain); i++) {
1520 x = sk_X509_value(ctx->chain, i);
1521 if (!(x->ex_flags & EXFLAG_INVALID_POLICY))
1523 ctx->current_cert = x;
1524 ctx->error = X509_V_ERR_INVALID_POLICY_EXTENSION;
1525 if (!ctx->verify_cb(0, ctx))
1531 ctx->current_cert = NULL;
1532 ctx->error = X509_V_ERR_NO_EXPLICIT_POLICY;
1533 return ctx->verify_cb(0, ctx);
1536 if (ctx->param->flags & X509_V_FLAG_NOTIFY_POLICY) {
1537 ctx->current_cert = NULL;
1538 ctx->error = X509_V_OK;
1539 if (!ctx->verify_cb(2, ctx))
1546 int x509_check_cert_time(X509_STORE_CTX *ctx, X509 *x, int quiet)
1551 if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME)
1552 ptime = &ctx->param->check_time;
1553 else if (ctx->param->flags & X509_V_FLAG_NO_CHECK_TIME)
1558 i = X509_cmp_time(X509_get_notBefore(x), ptime);
1562 ctx->error = X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD;
1563 ctx->current_cert = x;
1564 if (!ctx->verify_cb(0, ctx))
1571 ctx->error = X509_V_ERR_CERT_NOT_YET_VALID;
1572 ctx->current_cert = x;
1573 if (!ctx->verify_cb(0, ctx))
1577 i = X509_cmp_time(X509_get_notAfter(x), ptime);
1581 ctx->error = X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD;
1582 ctx->current_cert = x;
1583 if (!ctx->verify_cb(0, ctx))
1590 ctx->error = X509_V_ERR_CERT_HAS_EXPIRED;
1591 ctx->current_cert = x;
1592 if (!ctx->verify_cb(0, ctx))
1599 static int internal_verify(X509_STORE_CTX *ctx)
1603 EVP_PKEY *pkey = NULL;
1605 n = sk_X509_num(ctx->chain) - 1;
1606 ctx->error_depth = n;
1607 xi = sk_X509_value(ctx->chain, n);
1610 * With DANE-verified bare public key TA signatures, it remains only to
1611 * check the timestamps of the top certificate. We report the issuer as
1612 * NULL, since all we have is a bare key.
1614 if (ctx->bare_ta_signed) {
1620 if (ctx->check_issued(ctx, xi, xi))
1623 if (ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) {
1628 ctx->error = X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE;
1629 ctx->current_cert = xi;
1630 ok = ctx->verify_cb(0, ctx);
1634 ctx->error_depth = n;
1635 xs = sk_X509_value(ctx->chain, n);
1640 * Do not clear ctx->error=0, it must be "sticky", only the user's callback
1641 * is allowed to reset errors (at its own peril).
1644 ctx->error_depth = n;
1647 * Skip signature check for self signed certificates unless
1648 * explicitly asked for. It doesn't add any security and just wastes
1651 if (xs != xi || (ctx->param->flags & X509_V_FLAG_CHECK_SS_SIGNATURE)) {
1652 if ((pkey = X509_get0_pubkey(xi)) == NULL) {
1653 ctx->error = X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY;
1654 ctx->current_cert = xi;
1655 ok = ctx->verify_cb(0, ctx);
1658 } else if (X509_verify(xs, pkey) <= 0) {
1659 ctx->error = X509_V_ERR_CERT_SIGNATURE_FAILURE;
1660 ctx->current_cert = xs;
1661 ok = ctx->verify_cb(0, ctx);
1668 ok = x509_check_cert_time(ctx, xs, 0);
1672 /* The last error (if any) is still in the error value */
1673 ctx->current_issuer = xi;
1674 ctx->current_cert = xs;
1675 ok = ctx->verify_cb(1, ctx);
1682 xs = sk_X509_value(ctx->chain, n);
1690 int X509_cmp_current_time(const ASN1_TIME *ctm)
1692 return X509_cmp_time(ctm, NULL);
1695 int X509_cmp_time(const ASN1_TIME *ctm, time_t *cmp_time)
1700 char buff1[24], buff2[24], *p;
1701 int i, j, remaining;
1704 remaining = ctm->length;
1705 str = (char *)ctm->data;
1707 * Note that the following (historical) code allows much more slack in the
1708 * time format than RFC5280. In RFC5280, the representation is fixed:
1709 * UTCTime: YYMMDDHHMMSSZ
1710 * GeneralizedTime: YYYYMMDDHHMMSSZ
1712 if (ctm->type == V_ASN1_UTCTIME) {
1713 /* YYMMDDHHMM[SS]Z or YYMMDDHHMM[SS](+-)hhmm */
1714 int min_length = sizeof("YYMMDDHHMMZ") - 1;
1715 int max_length = sizeof("YYMMDDHHMMSS+hhmm") - 1;
1716 if (remaining < min_length || remaining > max_length)
1723 /* YYYYMMDDHHMM[SS[.fff]]Z or YYYYMMDDHHMM[SS[.f[f[f]]]](+-)hhmm */
1724 int min_length = sizeof("YYYYMMDDHHMMZ") - 1;
1725 int max_length = sizeof("YYYYMMDDHHMMSS.fff+hhmm") - 1;
1726 if (remaining < min_length || remaining > max_length)
1734 if ((*str == 'Z') || (*str == '-') || (*str == '+')) {
1745 * Skip any (up to three) fractional seconds...
1746 * TODO(emilia): in RFC5280, fractional seconds are forbidden.
1747 * Can we just kill them altogether?
1749 if (remaining && *str == '.') {
1752 for (i = 0; i < 3 && remaining; i++, str++, remaining--) {
1753 if (*str < '0' || *str > '9')
1762 /* We now need either a terminating 'Z' or an offset. */
1771 if ((*str != '+') && (*str != '-'))
1773 /* Historical behaviour: the (+-)hhmm offset is forbidden in RFC5280. */
1776 if (str[1] < '0' || str[1] > '9' || str[2] < '0' || str[2] > '9' ||
1777 str[3] < '0' || str[3] > '9' || str[4] < '0' || str[4] > '9')
1779 offset = ((str[1] - '0') * 10 + (str[2] - '0')) * 60;
1780 offset += (str[3] - '0') * 10 + (str[4] - '0');
1784 atm.type = ctm->type;
1786 atm.length = sizeof(buff2);
1787 atm.data = (unsigned char *)buff2;
1789 if (X509_time_adj(&atm, offset * 60, cmp_time) == NULL)
1792 if (ctm->type == V_ASN1_UTCTIME) {
1793 i = (buff1[0] - '0') * 10 + (buff1[1] - '0');
1795 i += 100; /* cf. RFC 2459 */
1796 j = (buff2[0] - '0') * 10 + (buff2[1] - '0');
1805 i = strcmp(buff1, buff2);
1806 if (i == 0) /* wait a second then return younger :-) */
1812 ASN1_TIME *X509_gmtime_adj(ASN1_TIME *s, long adj)
1814 return X509_time_adj(s, adj, NULL);
1817 ASN1_TIME *X509_time_adj(ASN1_TIME *s, long offset_sec, time_t *in_tm)
1819 return X509_time_adj_ex(s, 0, offset_sec, in_tm);
1822 ASN1_TIME *X509_time_adj_ex(ASN1_TIME *s,
1823 int offset_day, long offset_sec, time_t *in_tm)
1832 if (s && !(s->flags & ASN1_STRING_FLAG_MSTRING)) {
1833 if (s->type == V_ASN1_UTCTIME)
1834 return ASN1_UTCTIME_adj(s, t, offset_day, offset_sec);
1835 if (s->type == V_ASN1_GENERALIZEDTIME)
1836 return ASN1_GENERALIZEDTIME_adj(s, t, offset_day, offset_sec);
1838 return ASN1_TIME_adj(s, t, offset_day, offset_sec);
1841 int X509_get_pubkey_parameters(EVP_PKEY *pkey, STACK_OF(X509) *chain)
1843 EVP_PKEY *ktmp = NULL, *ktmp2;
1846 if ((pkey != NULL) && !EVP_PKEY_missing_parameters(pkey))
1849 for (i = 0; i < sk_X509_num(chain); i++) {
1850 ktmp = X509_get0_pubkey(sk_X509_value(chain, i));
1852 X509err(X509_F_X509_GET_PUBKEY_PARAMETERS,
1853 X509_R_UNABLE_TO_GET_CERTS_PUBLIC_KEY);
1856 if (!EVP_PKEY_missing_parameters(ktmp))
1860 X509err(X509_F_X509_GET_PUBKEY_PARAMETERS,
1861 X509_R_UNABLE_TO_FIND_PARAMETERS_IN_CHAIN);
1865 /* first, populate the other certs */
1866 for (j = i - 1; j >= 0; j--) {
1867 ktmp2 = X509_get0_pubkey(sk_X509_value(chain, j));
1868 EVP_PKEY_copy_parameters(ktmp2, ktmp);
1872 EVP_PKEY_copy_parameters(pkey, ktmp);
1876 /* Make a delta CRL as the diff between two full CRLs */
1878 X509_CRL *X509_CRL_diff(X509_CRL *base, X509_CRL *newer,
1879 EVP_PKEY *skey, const EVP_MD *md, unsigned int flags)
1881 X509_CRL *crl = NULL;
1883 STACK_OF(X509_REVOKED) *revs = NULL;
1884 /* CRLs can't be delta already */
1885 if (base->base_crl_number || newer->base_crl_number) {
1886 X509err(X509_F_X509_CRL_DIFF, X509_R_CRL_ALREADY_DELTA);
1889 /* Base and new CRL must have a CRL number */
1890 if (!base->crl_number || !newer->crl_number) {
1891 X509err(X509_F_X509_CRL_DIFF, X509_R_NO_CRL_NUMBER);
1894 /* Issuer names must match */
1895 if (X509_NAME_cmp(X509_CRL_get_issuer(base), X509_CRL_get_issuer(newer))) {
1896 X509err(X509_F_X509_CRL_DIFF, X509_R_ISSUER_MISMATCH);
1899 /* AKID and IDP must match */
1900 if (!crl_extension_match(base, newer, NID_authority_key_identifier)) {
1901 X509err(X509_F_X509_CRL_DIFF, X509_R_AKID_MISMATCH);
1904 if (!crl_extension_match(base, newer, NID_issuing_distribution_point)) {
1905 X509err(X509_F_X509_CRL_DIFF, X509_R_IDP_MISMATCH);
1908 /* Newer CRL number must exceed full CRL number */
1909 if (ASN1_INTEGER_cmp(newer->crl_number, base->crl_number) <= 0) {
1910 X509err(X509_F_X509_CRL_DIFF, X509_R_NEWER_CRL_NOT_NEWER);
1913 /* CRLs must verify */
1914 if (skey && (X509_CRL_verify(base, skey) <= 0 ||
1915 X509_CRL_verify(newer, skey) <= 0)) {
1916 X509err(X509_F_X509_CRL_DIFF, X509_R_CRL_VERIFY_FAILURE);
1919 /* Create new CRL */
1920 crl = X509_CRL_new();
1921 if (crl == NULL || !X509_CRL_set_version(crl, 1))
1923 /* Set issuer name */
1924 if (!X509_CRL_set_issuer_name(crl, X509_CRL_get_issuer(newer)))
1927 if (!X509_CRL_set_lastUpdate(crl, X509_CRL_get_lastUpdate(newer)))
1929 if (!X509_CRL_set_nextUpdate(crl, X509_CRL_get_nextUpdate(newer)))
1932 /* Set base CRL number: must be critical */
1934 if (!X509_CRL_add1_ext_i2d(crl, NID_delta_crl, base->crl_number, 1, 0))
1938 * Copy extensions across from newest CRL to delta: this will set CRL
1939 * number to correct value too.
1942 for (i = 0; i < X509_CRL_get_ext_count(newer); i++) {
1943 X509_EXTENSION *ext;
1944 ext = X509_CRL_get_ext(newer, i);
1945 if (!X509_CRL_add_ext(crl, ext, -1))
1949 /* Go through revoked entries, copying as needed */
1951 revs = X509_CRL_get_REVOKED(newer);
1953 for (i = 0; i < sk_X509_REVOKED_num(revs); i++) {
1954 X509_REVOKED *rvn, *rvtmp;
1955 rvn = sk_X509_REVOKED_value(revs, i);
1957 * Add only if not also in base. TODO: need something cleverer here
1958 * for some more complex CRLs covering multiple CAs.
1960 if (!X509_CRL_get0_by_serial(base, &rvtmp, &rvn->serialNumber)) {
1961 rvtmp = X509_REVOKED_dup(rvn);
1964 if (!X509_CRL_add0_revoked(crl, rvtmp)) {
1965 X509_REVOKED_free(rvtmp);
1970 /* TODO: optionally prune deleted entries */
1972 if (skey && md && !X509_CRL_sign(crl, skey, md))
1978 X509err(X509_F_X509_CRL_DIFF, ERR_R_MALLOC_FAILURE);
1983 int X509_STORE_CTX_set_ex_data(X509_STORE_CTX *ctx, int idx, void *data)
1985 return CRYPTO_set_ex_data(&ctx->ex_data, idx, data);
1988 void *X509_STORE_CTX_get_ex_data(X509_STORE_CTX *ctx, int idx)
1990 return CRYPTO_get_ex_data(&ctx->ex_data, idx);
1993 int X509_STORE_CTX_get_error(X509_STORE_CTX *ctx)
1998 void X509_STORE_CTX_set_error(X509_STORE_CTX *ctx, int err)
2003 int X509_STORE_CTX_get_error_depth(X509_STORE_CTX *ctx)
2005 return ctx->error_depth;
2008 X509 *X509_STORE_CTX_get_current_cert(X509_STORE_CTX *ctx)
2010 return ctx->current_cert;
2013 STACK_OF(X509) *X509_STORE_CTX_get_chain(X509_STORE_CTX *ctx)
2018 STACK_OF(X509) *X509_STORE_CTX_get1_chain(X509_STORE_CTX *ctx)
2022 return X509_chain_up_ref(ctx->chain);
2025 X509 *X509_STORE_CTX_get0_current_issuer(X509_STORE_CTX *ctx)
2027 return ctx->current_issuer;
2030 X509_CRL *X509_STORE_CTX_get0_current_crl(X509_STORE_CTX *ctx)
2032 return ctx->current_crl;
2035 X509_STORE_CTX *X509_STORE_CTX_get0_parent_ctx(X509_STORE_CTX *ctx)
2040 void X509_STORE_CTX_set_cert(X509_STORE_CTX *ctx, X509 *x)
2045 void X509_STORE_CTX_set_chain(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2047 ctx->untrusted = sk;
2050 void X509_STORE_CTX_set0_crls(X509_STORE_CTX *ctx, STACK_OF(X509_CRL) *sk)
2055 int X509_STORE_CTX_set_purpose(X509_STORE_CTX *ctx, int purpose)
2058 * XXX: Why isn't this function always used to set the associated trust?
2059 * Should there even be a VPM->trust field at all? Or should the trust
2060 * always be inferred from the purpose by X509_STORE_CTX_init().
2062 return X509_STORE_CTX_purpose_inherit(ctx, 0, purpose, 0);
2065 int X509_STORE_CTX_set_trust(X509_STORE_CTX *ctx, int trust)
2068 * XXX: See above, this function would only be needed when the default
2069 * trust for the purpose needs an override in a corner case.
2071 return X509_STORE_CTX_purpose_inherit(ctx, 0, 0, trust);
2075 * This function is used to set the X509_STORE_CTX purpose and trust values.
2076 * This is intended to be used when another structure has its own trust and
2077 * purpose values which (if set) will be inherited by the ctx. If they aren't
2078 * set then we will usually have a default purpose in mind which should then
2079 * be used to set the trust value. An example of this is SSL use: an SSL
2080 * structure will have its own purpose and trust settings which the
2081 * application can set: if they aren't set then we use the default of SSL
2085 int X509_STORE_CTX_purpose_inherit(X509_STORE_CTX *ctx, int def_purpose,
2086 int purpose, int trust)
2089 /* If purpose not set use default */
2091 purpose = def_purpose;
2092 /* If we have a purpose then check it is valid */
2095 idx = X509_PURPOSE_get_by_id(purpose);
2097 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2098 X509_R_UNKNOWN_PURPOSE_ID);
2101 ptmp = X509_PURPOSE_get0(idx);
2102 if (ptmp->trust == X509_TRUST_DEFAULT) {
2103 idx = X509_PURPOSE_get_by_id(def_purpose);
2105 * XXX: In the two callers above def_purpose is always 0, which is
2106 * not a known value, so idx will always be -1. How is the
2107 * X509_TRUST_DEFAULT case actually supposed to be handled?
2110 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2111 X509_R_UNKNOWN_PURPOSE_ID);
2114 ptmp = X509_PURPOSE_get0(idx);
2116 /* If trust not set then get from purpose default */
2118 trust = ptmp->trust;
2121 idx = X509_TRUST_get_by_id(trust);
2123 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2124 X509_R_UNKNOWN_TRUST_ID);
2129 if (purpose && !ctx->param->purpose)
2130 ctx->param->purpose = purpose;
2131 if (trust && !ctx->param->trust)
2132 ctx->param->trust = trust;
2136 X509_STORE_CTX *X509_STORE_CTX_new(void)
2138 X509_STORE_CTX *ctx = OPENSSL_zalloc(sizeof(*ctx));
2141 X509err(X509_F_X509_STORE_CTX_NEW, ERR_R_MALLOC_FAILURE);
2147 void X509_STORE_CTX_free(X509_STORE_CTX *ctx)
2151 X509_STORE_CTX_cleanup(ctx);
2155 int X509_STORE_CTX_init(X509_STORE_CTX *ctx, X509_STORE *store, X509 *x509,
2156 STACK_OF(X509) *chain)
2161 ctx->current_method = 0;
2163 ctx->untrusted = chain;
2165 ctx->num_untrusted = 0;
2166 ctx->other_ctx = NULL;
2170 ctx->explicit_policy = 0;
2171 ctx->error_depth = 0;
2172 ctx->current_cert = NULL;
2173 ctx->current_issuer = NULL;
2174 ctx->current_crl = NULL;
2175 ctx->current_crl_score = 0;
2176 ctx->current_reasons = 0;
2180 ctx->bare_ta_signed = 0;
2181 /* Zero ex_data to make sure we're cleanup-safe */
2182 memset(&ctx->ex_data, 0, sizeof(ctx->ex_data));
2185 ctx->verify_cb = store->verify_cb;
2186 /* Seems to always be 0 in OpenSSL, else must be idempotent */
2187 ctx->cleanup = store->cleanup;
2191 if (store && store->check_issued)
2192 ctx->check_issued = store->check_issued;
2194 ctx->check_issued = check_issued;
2196 if (store && store->get_issuer)
2197 ctx->get_issuer = store->get_issuer;
2199 ctx->get_issuer = X509_STORE_CTX_get1_issuer;
2201 if (store && store->verify_cb)
2202 ctx->verify_cb = store->verify_cb;
2204 ctx->verify_cb = null_callback;
2206 if (store && store->verify)
2207 ctx->verify = store->verify;
2209 ctx->verify = internal_verify;
2211 if (store && store->check_revocation)
2212 ctx->check_revocation = store->check_revocation;
2214 ctx->check_revocation = check_revocation;
2216 if (store && store->get_crl)
2217 ctx->get_crl = store->get_crl;
2219 ctx->get_crl = NULL;
2221 if (store && store->check_crl)
2222 ctx->check_crl = store->check_crl;
2224 ctx->check_crl = check_crl;
2226 if (store && store->cert_crl)
2227 ctx->cert_crl = store->cert_crl;
2229 ctx->cert_crl = cert_crl;
2231 if (store && store->lookup_certs)
2232 ctx->lookup_certs = store->lookup_certs;
2234 ctx->lookup_certs = X509_STORE_get1_certs;
2236 if (store && store->lookup_crls)
2237 ctx->lookup_crls = store->lookup_crls;
2239 ctx->lookup_crls = X509_STORE_get1_crls;
2241 ctx->check_policy = check_policy;
2243 ctx->param = X509_VERIFY_PARAM_new();
2244 if (ctx->param == NULL) {
2245 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2250 * Inherit callbacks and flags from X509_STORE if not set use defaults.
2253 ret = X509_VERIFY_PARAM_inherit(ctx->param, store->param);
2255 ctx->param->inh_flags |= X509_VP_FLAG_DEFAULT | X509_VP_FLAG_ONCE;
2258 ret = X509_VERIFY_PARAM_inherit(ctx->param,
2259 X509_VERIFY_PARAM_lookup("default"));
2262 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2267 * XXX: For now, continue to inherit trust from VPM, but infer from the
2268 * purpose if this still yields the default value.
2270 if (ctx->param->trust == X509_TRUST_DEFAULT) {
2271 int idx = X509_PURPOSE_get_by_id(ctx->param->purpose);
2272 X509_PURPOSE *xp = X509_PURPOSE_get0(idx);
2275 ctx->param->trust = X509_PURPOSE_get_trust(xp);
2278 if (CRYPTO_new_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx,
2281 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2285 * On error clean up allocated storage, if the store context was not
2286 * allocated with X509_STORE_CTX_new() this is our last chance to do so.
2288 X509_STORE_CTX_cleanup(ctx);
2293 * Set alternative lookup method: just a STACK of trusted certificates. This
2294 * avoids X509_STORE nastiness where it isn't needed.
2297 void X509_STORE_CTX_trusted_stack(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2299 ctx->other_ctx = sk;
2300 ctx->get_issuer = get_issuer_sk;
2301 ctx->lookup_certs = lookup_certs_sk;
2304 void X509_STORE_CTX_cleanup(X509_STORE_CTX *ctx)
2307 * We need to be idempotent because, unfortunately, free() also calls
2308 * cleanup(), so the natural call sequence new(), init(), cleanup(), free()
2309 * calls cleanup() for the same object twice! Thus we must zero the
2310 * pointers below after they're freed!
2312 /* Seems to always be 0 in OpenSSL, do this at most once. */
2313 if (ctx->cleanup != NULL) {
2315 ctx->cleanup = NULL;
2317 if (ctx->param != NULL) {
2318 if (ctx->parent == NULL)
2319 X509_VERIFY_PARAM_free(ctx->param);
2322 X509_policy_tree_free(ctx->tree);
2324 sk_X509_pop_free(ctx->chain, X509_free);
2326 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx, &(ctx->ex_data));
2327 memset(&ctx->ex_data, 0, sizeof(ctx->ex_data));
2330 void X509_STORE_CTX_set_depth(X509_STORE_CTX *ctx, int depth)
2332 X509_VERIFY_PARAM_set_depth(ctx->param, depth);
2335 void X509_STORE_CTX_set_flags(X509_STORE_CTX *ctx, unsigned long flags)
2337 X509_VERIFY_PARAM_set_flags(ctx->param, flags);
2340 void X509_STORE_CTX_set_time(X509_STORE_CTX *ctx, unsigned long flags,
2343 X509_VERIFY_PARAM_set_time(ctx->param, t);
2346 void X509_STORE_CTX_set_verify_cb(X509_STORE_CTX *ctx,
2347 int (*verify_cb) (int, X509_STORE_CTX *))
2349 ctx->verify_cb = verify_cb;
2352 X509_POLICY_TREE *X509_STORE_CTX_get0_policy_tree(X509_STORE_CTX *ctx)
2357 int X509_STORE_CTX_get_explicit_policy(X509_STORE_CTX *ctx)
2359 return ctx->explicit_policy;
2362 int X509_STORE_CTX_get_num_untrusted(X509_STORE_CTX *ctx)
2364 return ctx->num_untrusted;
2367 int X509_STORE_CTX_set_default(X509_STORE_CTX *ctx, const char *name)
2369 const X509_VERIFY_PARAM *param;
2370 param = X509_VERIFY_PARAM_lookup(name);
2373 return X509_VERIFY_PARAM_inherit(ctx->param, param);
2376 X509_VERIFY_PARAM *X509_STORE_CTX_get0_param(X509_STORE_CTX *ctx)
2381 void X509_STORE_CTX_set0_param(X509_STORE_CTX *ctx, X509_VERIFY_PARAM *param)
2383 X509_VERIFY_PARAM_free(ctx->param);
2387 void X509_STORE_CTX_set0_dane(X509_STORE_CTX *ctx, struct dane_st *dane)
2392 static unsigned char *dane_i2d(
2395 unsigned int *i2dlen)
2397 unsigned char *buf = NULL;
2401 * Extract ASN.1 DER form of certificate or public key.
2404 case DANETLS_SELECTOR_CERT:
2405 len = i2d_X509(cert, &buf);
2407 case DANETLS_SELECTOR_SPKI:
2408 len = i2d_X509_PUBKEY(X509_get_X509_PUBKEY(cert), &buf);
2411 X509err(X509_F_DANE_I2D, X509_R_BAD_SELECTOR);
2415 if (len < 0 || buf == NULL) {
2416 X509err(X509_F_DANE_I2D, ERR_R_MALLOC_FAILURE);
2420 *i2dlen = (unsigned int)len;
2424 #define DANETLS_NONE 256 /* impossible uint8_t */
2426 static int dane_match(X509_STORE_CTX *ctx, X509 *cert, int depth)
2428 struct dane_st *dane = (struct dane_st *)ctx->dane;
2429 unsigned usage = DANETLS_NONE;
2430 unsigned selector = DANETLS_NONE;
2431 unsigned ordinal = DANETLS_NONE;
2432 unsigned mtype = DANETLS_NONE;
2433 unsigned char *i2dbuf = NULL;
2434 unsigned int i2dlen = 0;
2435 unsigned char mdbuf[EVP_MAX_MD_SIZE];
2436 unsigned char *cmpbuf = NULL;
2437 unsigned int cmplen = 0;
2441 danetls_record *t = NULL;
2444 mask = (depth == 0) ? DANETLS_EE_MASK : DANETLS_TA_MASK;
2447 * The trust store is not applicable with DANE-TA(2)
2449 if (depth >= ctx->num_untrusted)
2450 mask &= DANETLS_PKIX_MASK;
2453 * If we've previously matched a PKIX-?? record, no need to test any
2454 * furher PKIX-?? records, it remains to just build the PKIX chain.
2455 * Had the match been a DANE-?? record, we'd be done already.
2457 if (dane->mdpth >= 0)
2458 mask &= ~DANETLS_PKIX_MASK;
2461 * https://tools.ietf.org/html/rfc7671#section-5.1
2462 * https://tools.ietf.org/html/rfc7671#section-5.2
2463 * https://tools.ietf.org/html/rfc7671#section-5.3
2464 * https://tools.ietf.org/html/rfc7671#section-5.4
2466 * We handle DANE-EE(3) records first as they require no chain building
2467 * and no expiration or hostname checks. We also process digests with
2468 * higher ordinals first and ignore lower priorities except Full(0) which
2469 * is always processed (last). If none match, we then process PKIX-EE(1).
2471 * NOTE: This relies on DANE usages sorting before the corresponding PKIX
2472 * usages in SSL_dane_tlsa_add(), and also on descending sorting of digest
2473 * priorities. See twin comment in ssl/ssl_lib.c.
2475 * We expect that most TLSA RRsets will have just a single usage, so we
2476 * don't go out of our way to cache multiple selector-specific i2d buffers
2477 * across usages, but if the selector happens to remain the same as switch
2478 * usages, that's OK. Thus, a set of "3 1 1", "3 0 1", "1 1 1", "1 0 1",
2479 * records would result in us generating each of the certificate and public
2480 * key DER forms twice, but more typically we'd just see multiple "3 1 1"
2481 * or multiple "3 0 1" records.
2483 * As soon as we find a match at any given depth, we stop, because either
2484 * we've matched a DANE-?? record and the peer is authenticated, or, after
2485 * exhausing all DANE-?? records, we've matched a PKIX-?? record, which is
2486 * sufficient for DANE, and what remains to do is ordinary PKIX validation.
2488 recnum = (dane->umask & mask) ? sk_danetls_record_num(dane->trecs) : 0;
2489 for (i = 0; matched == 0 && i < recnum; ++i) {
2490 t = sk_danetls_record_value(dane->trecs, i);
2491 if ((DANETLS_USAGE_BIT(t->usage) & mask) == 0)
2493 if (t->usage != usage) {
2496 /* Reset digest agility for each usage/selector pair */
2497 mtype = DANETLS_NONE;
2498 ordinal = dane->dctx->mdord[t->mtype];
2500 if (t->selector != selector) {
2501 selector = t->selector;
2503 /* Update per-selector state */
2504 OPENSSL_free(i2dbuf);
2505 i2dbuf = dane_i2d(cert, selector, &i2dlen);
2509 /* Reset digest agility for each usage/selector pair */
2510 mtype = DANETLS_NONE;
2511 ordinal = dane->dctx->mdord[t->mtype];
2512 } else if (t->mtype != DANETLS_MATCHING_FULL) {
2516 * <https://tools.ietf.org/html/rfc7671#section-9>
2518 * For a fixed selector, after processing all records with the
2519 * highest mtype ordinal, ignore all mtypes with lower ordinals
2520 * other than "Full".
2522 if (dane->dctx->mdord[t->mtype] < ordinal)
2527 * Each time we hit a (new selector or) mtype, re-compute the relevant
2528 * digest, more complex caching is not worth the code space.
2530 if (t->mtype != mtype) {
2531 const EVP_MD *md = dane->dctx->mdevp[mtype = t->mtype];
2537 if (!EVP_Digest(i2dbuf, i2dlen, cmpbuf, &cmplen, md, 0)) {
2545 * Squirrel away the certificate and depth if we have a match. Any
2546 * DANE match is dispositive, but with PKIX we still need to build a
2549 if (cmplen == t->dlen &&
2550 memcmp(cmpbuf, t->data, cmplen) == 0) {
2551 if (DANETLS_USAGE_BIT(usage) & DANETLS_DANE_MASK)
2553 if (matched || dane->mdpth < 0) {
2554 dane->mdpth = depth;
2556 OPENSSL_free(dane->mcert);
2564 /* Clear the one-element DER cache */
2565 OPENSSL_free(i2dbuf);
2569 static int check_dane_issuer(X509_STORE_CTX *ctx, int depth)
2571 struct dane_st *dane = (struct dane_st *)ctx->dane;
2575 if (!DANETLS_HAS_TA(dane) || depth == 0)
2576 return X509_TRUST_UNTRUSTED;
2579 * Record any DANE trust anchor matches, for the first depth to test, if
2580 * there's one at that depth. (This'll be false for length 1 chains looking
2581 * for an exact match for the leaf certificate).
2583 cert = sk_X509_value(ctx->chain, depth);
2584 if (cert != NULL && (matched = dane_match(ctx, cert, depth)) < 0)
2585 return X509_TRUST_REJECTED;
2587 ctx->num_untrusted = depth - 1;
2588 return X509_TRUST_TRUSTED;
2591 return X509_TRUST_UNTRUSTED;
2594 static int check_dane_pkeys(X509_STORE_CTX *ctx)
2596 struct dane_st *dane = (struct dane_st *)ctx->dane;
2598 int num = ctx->num_untrusted;
2599 X509 *cert = sk_X509_value(ctx->chain, num - 1);
2600 int recnum = sk_danetls_record_num(dane->trecs);
2603 for (i = 0; i < recnum; ++i) {
2604 t = sk_danetls_record_value(dane->trecs, i);
2605 if (t->usage != DANETLS_USAGE_DANE_TA ||
2606 t->selector != DANETLS_SELECTOR_SPKI ||
2607 t->mtype != DANETLS_MATCHING_FULL ||
2608 X509_verify(cert, t->spki) <= 0)
2611 /* Clear PKIX-?? matches that failed to panned out to a full chain */
2612 X509_free(dane->mcert);
2615 /* Record match via a bare TA public key */
2616 ctx->bare_ta_signed = 1;
2617 dane->mdpth = num - 1;
2620 /* Prune any excess chain certificates */
2621 num = sk_X509_num(ctx->chain);
2622 for (; num > ctx->num_untrusted; --num)
2623 X509_free(sk_X509_pop(ctx->chain));
2625 return X509_TRUST_TRUSTED;
2628 return X509_TRUST_UNTRUSTED;
2631 static void dane_reset(struct dane_st *dane)
2634 * Reset state to verify another chain, or clear after failure.
2636 X509_free(dane->mcert);
2643 static int check_leaf_suiteb(X509_STORE_CTX *ctx, X509 *cert)
2645 int err = X509_chain_check_suiteb(NULL, cert, NULL, ctx->param->flags);
2647 if (err == X509_V_OK)
2649 ctx->current_cert = cert;
2650 ctx->error_depth = 0;
2652 return ctx->verify_cb(0, ctx);
2655 static int dane_verify(X509_STORE_CTX *ctx)
2657 X509 *cert = ctx->cert;
2658 struct dane_st *dane = (struct dane_st *)ctx->dane;
2664 matched = dane_match(ctx, ctx->cert, 0);
2665 done = matched != 0 || (!DANETLS_HAS_TA(dane) && dane->mdpth < 0);
2668 X509_get_pubkey_parameters(NULL, ctx->chain);
2671 if (!check_leaf_suiteb(ctx, cert))
2673 ctx->error_depth = 0;
2674 ctx->current_cert = cert;
2675 return ctx->verify_cb(1, ctx);
2679 ctx->error_depth = 0;
2680 ctx->current_cert = cert;
2681 ctx->error = X509_V_ERR_OUT_OF_MEM;
2686 /* Fail early, TA-based success is not possible */
2687 if (!check_leaf_suiteb(ctx, cert))
2689 ctx->current_cert = cert;
2690 ctx->error_depth = 0;
2691 ctx->error = X509_V_ERR_CERT_UNTRUSTED;
2692 return ctx->verify_cb(0, ctx);
2696 * Chain verification for usages 0/1/2. TLSA record matching of depth > 0
2697 * certificates happens in-line with building the rest of the chain.
2699 return verify_chain(ctx);
2702 static int build_chain(X509_STORE_CTX *ctx)
2704 struct dane_st *dane = (struct dane_st *)ctx->dane;
2705 int num = sk_X509_num(ctx->chain);
2706 X509 *cert = sk_X509_value(ctx->chain, num - 1);
2707 int ss = cert_self_signed(cert);
2708 STACK_OF(X509) *sktmp = NULL;
2709 unsigned int search;
2710 int may_trusted = 0;
2711 int may_alternate = 0;
2712 int trust = X509_TRUST_UNTRUSTED;
2713 int alt_untrusted = 0;
2718 /* Our chain starts with a single untrusted element. */
2719 OPENSSL_assert(num == 1 && ctx->num_untrusted == num);
2721 #define S_DOUNTRUSTED (1 << 0) /* Search untrusted chain */
2722 #define S_DOTRUSTED (1 << 1) /* Search trusted store */
2723 #define S_DOALTERNATE (1 << 2) /* Retry with pruned alternate chain */
2725 * Set up search policy, untrusted if possible, trusted-first if enabled.
2726 * If we're doing DANE and not doing PKIX-TA/PKIX-EE, we never look in the
2727 * trust_store, otherwise we might look there first. If not trusted-first,
2728 * and alternate chains are not disabled, try building an alternate chain
2729 * if no luck with untrusted first.
2731 search = (ctx->untrusted != NULL) ? S_DOUNTRUSTED : 0;
2732 if (DANETLS_HAS_PKIX(dane) || !DANETLS_HAS_DANE(dane)) {
2733 if (search == 0 || ctx->param->flags & X509_V_FLAG_TRUSTED_FIRST)
2734 search |= S_DOTRUSTED;
2735 else if (!(ctx->param->flags & X509_V_FLAG_NO_ALT_CHAINS))
2741 * Shallow-copy the stack of untrusted certificates (with TLS, this is
2742 * typically the content of the peer's certificate message) so can make
2743 * multiple passes over it, while free to remove elements as we go.
2745 if (ctx->untrusted && (sktmp = sk_X509_dup(ctx->untrusted)) == NULL) {
2746 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2750 /* Include any untrusted full certificates from DNS */
2751 if (DANETLS_ENABLED(dane) && dane->certs != NULL) {
2752 for (i = 0; i < sk_X509_num(dane->certs); ++i) {
2753 if (!sk_X509_push(sktmp, sk_X509_value(dane->certs, i))) {
2754 sk_X509_free(sktmp);
2755 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2762 * Still absurdly large, but arithmetically safe, a lower hard upper bound
2763 * might be reasonable.
2765 if (ctx->param->depth > INT_MAX/2)
2766 ctx->param->depth = INT_MAX/2;
2769 * Try to Extend the chain until we reach an ultimately trusted issuer.
2770 * Build chains up to one longer the limit, later fail if we hit the limit,
2771 * with an X509_V_ERR_CERT_CHAIN_TOO_LONG error code.
2773 depth = ctx->param->depth + 1;
2775 while (search != 0) {
2780 * Look in the trust store if enabled for first lookup, or we've run
2781 * out of untrusted issuers and search here is not disabled. When
2782 * we exceed the depth limit, we simulate absence of a match.
2784 if ((search & S_DOTRUSTED) != 0) {
2785 STACK_OF(X509) *hide = ctx->chain;
2787 i = num = sk_X509_num(ctx->chain);
2788 if ((search & S_DOALTERNATE) != 0) {
2790 * As high up the chain as we can, look for an alternative
2791 * trusted issuer of an untrusted certificate that currently
2792 * has an untrusted issuer. We use the alt_untrusted variable
2793 * to track how far up the chain we find the first match. It
2794 * is only if and when we find a match, that we prune the chain
2795 * and reset ctx->num_untrusted to the reduced count of
2796 * untrusted certificates. While we're searching for such a
2797 * match (which may never be found), it is neither safe nor
2798 * wise to preemptively modify either the chain or
2799 * ctx->num_untrusted.
2801 * Note, like ctx->num_untrusted, alt_untrusted is a count of
2802 * untrusted certificates, not a "depth".
2806 x = sk_X509_value(ctx->chain, i-1);
2808 /* Suppress duplicate suppression */
2810 ok = (depth < num) ? 0 : ctx->get_issuer(&xtmp, ctx, x);
2814 trust = X509_TRUST_REJECTED;
2821 * Alternative trusted issuer for a mid-chain untrusted cert?
2822 * Pop the untrusted cert's successors and retry. We might now
2823 * be able to complete a valid chain via the trust store. Note
2824 * that despite the current trust-store match we might still
2825 * fail complete the chain to a suitable trust-anchor, in which
2826 * case we may prune some more untrusted certificates and try
2827 * again. Thus the S_DOALTERNATE bit may yet be turned on
2828 * again with an even shorter untrusted chain!
2830 * If in the process we threw away our matching PKIX-TA trust
2831 * anchor, reset DANE trust. We might find a suitable trusted
2832 * certificate among the ones from the trust store.
2834 if ((search & S_DOALTERNATE) != 0) {
2835 OPENSSL_assert(num > i && i > 0 && ss == 0);
2836 search &= ~S_DOALTERNATE;
2837 for (; num > i; --num)
2838 X509_free(sk_X509_pop(ctx->chain));
2839 ctx->num_untrusted = num;
2841 if (DANETLS_ENABLED(dane) &&
2842 dane->mdpth >= ctx->num_untrusted) {
2844 X509_free(dane->mcert);
2847 if (DANETLS_ENABLED(dane) &&
2848 dane->pdpth >= ctx->num_untrusted)
2853 * Self-signed untrusted certificates get replaced by their
2854 * trusted matching issuer. Otherwise, grow the chain.
2857 if (!sk_X509_push(ctx->chain, x = xtmp)) {
2859 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2860 trust = X509_TRUST_REJECTED;
2864 ss = cert_self_signed(x);
2865 } else if (num == ctx->num_untrusted) {
2867 * We have a self-signed certificate that has the same
2868 * subject name (and perhaps keyid and/or serial number) as
2869 * a trust-anchor. We must have an exact match to avoid
2870 * possible impersonation via key substitution etc.
2872 if (X509_cmp(x, xtmp) != 0) {
2873 /* Self-signed untrusted mimic. */
2878 ctx->num_untrusted = --num;
2879 (void) sk_X509_set(ctx->chain, num, x = xtmp);
2884 * We've added a new trusted certificate to the chain, recheck
2885 * trust. If not done, and not self-signed look deeper.
2886 * Whether or not we're doing "trusted first", we no longer
2887 * look for untrusted certificates from the peer's chain.
2889 * At this point ctx->num_trusted and num must reflect the
2890 * correct number of untrusted certificates, since the DANE
2891 * logic in check_trust() depends on distinguishing CAs from
2892 * "the wire" from CAs from the trust store. In particular, the
2893 * certificate at depth "num" should be the new trusted
2894 * certificate with ctx->num_untrusted <= num.
2897 OPENSSL_assert(ctx->num_untrusted <= num);
2898 search &= ~S_DOUNTRUSTED;
2899 switch (trust = check_trust(ctx, num)) {
2900 case X509_TRUST_TRUSTED:
2901 case X509_TRUST_REJECTED:
2911 * No dispositive decision, and either self-signed or no match, if
2912 * we were doing untrusted-first, and alt-chains are not disabled,
2913 * do that, by repeatedly losing one untrusted element at a time,
2914 * and trying to extend the shorted chain.
2916 if ((search & S_DOUNTRUSTED) == 0) {
2917 /* Continue search for a trusted issuer of a shorter chain? */
2918 if ((search & S_DOALTERNATE) != 0 && --alt_untrusted > 0)
2920 /* Still no luck and no fallbacks left? */
2921 if (!may_alternate || (search & S_DOALTERNATE) != 0 ||
2922 ctx->num_untrusted < 2)
2924 /* Search for a trusted issuer of a shorter chain */
2925 search |= S_DOALTERNATE;
2926 alt_untrusted = ctx->num_untrusted - 1;
2932 * Extend chain with peer-provided certificates
2934 if ((search & S_DOUNTRUSTED) != 0) {
2935 num = sk_X509_num(ctx->chain);
2936 OPENSSL_assert(num == ctx->num_untrusted);
2937 x = sk_X509_value(ctx->chain, num-1);
2938 xtmp = (depth < num) ? NULL : find_issuer(ctx, sktmp, x);
2941 * Once we run out of untrusted issuers, we stop looking for more
2942 * and start looking only in the trust store if enabled.
2945 search &= ~S_DOUNTRUSTED;
2947 search |= S_DOTRUSTED;
2951 if (!sk_X509_push(ctx->chain, x = xtmp)) {
2952 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2953 trust = X509_TRUST_REJECTED;
2958 ++ctx->num_untrusted;
2959 ss = cert_self_signed(xtmp);
2962 * Not strictly necessary, but saves cycles looking at the same
2963 * certificates over and over.
2965 (void) sk_X509_delete_ptr(sktmp, x);
2968 * Check for DANE-TA trust of the topmost untrusted certificate.
2970 switch (trust = check_dane_issuer(ctx, ctx->num_untrusted - 1)) {
2971 case X509_TRUST_TRUSTED:
2972 case X509_TRUST_REJECTED:
2978 sk_X509_free(sktmp);
2981 * Last chance to make a trusted chain, either bare DANE-TA public-key
2982 * signers, or else direct leaf PKIX trust.
2984 num = sk_X509_num(ctx->chain);
2986 if (trust == X509_TRUST_UNTRUSTED && DANETLS_HAS_DANE_TA(dane))
2987 trust = check_dane_pkeys(ctx);
2988 if (trust == X509_TRUST_UNTRUSTED && num == ctx->num_untrusted)
2989 trust = check_trust(ctx, num);
2993 case X509_TRUST_TRUSTED:
2995 case X509_TRUST_REJECTED:
2997 case X509_TRUST_UNTRUSTED:
2999 num = sk_X509_num(ctx->chain);
3000 ctx->current_cert = sk_X509_value(ctx->chain, num - 1);
3001 ctx->error_depth = num-1;
3003 ctx->error = X509_V_ERR_CERT_CHAIN_TOO_LONG;
3004 else if (DANETLS_ENABLED(dane) &&
3005 (!DANETLS_HAS_PKIX(dane) || dane->pdpth >= 0))
3006 ctx->error = X509_V_ERR_CERT_UNTRUSTED;
3007 else if (ss && sk_X509_num(ctx->chain) == 1)
3008 ctx->error = X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT;
3010 ctx->error = X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN;
3011 else if (ctx->num_untrusted == num)
3012 ctx->error = X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY;
3014 ctx->error = X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT;
3015 if (DANETLS_ENABLED(dane))
3017 return ctx->verify_cb(0, ctx);