2 * Copyright 1995-2020 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the OpenSSL license (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
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"
28 /* CRL score values */
30 /* No unhandled critical extensions */
32 #define CRL_SCORE_NOCRITICAL 0x100
34 /* certificate is within CRL scope */
36 #define CRL_SCORE_SCOPE 0x080
40 #define CRL_SCORE_TIME 0x040
42 /* Issuer name matches certificate */
44 #define CRL_SCORE_ISSUER_NAME 0x020
46 /* If this score or above CRL is probably valid */
48 #define CRL_SCORE_VALID (CRL_SCORE_NOCRITICAL|CRL_SCORE_TIME|CRL_SCORE_SCOPE)
50 /* CRL issuer is certificate issuer */
52 #define CRL_SCORE_ISSUER_CERT 0x018
54 /* CRL issuer is on certificate path */
56 #define CRL_SCORE_SAME_PATH 0x008
58 /* CRL issuer matches CRL AKID */
60 #define CRL_SCORE_AKID 0x004
62 /* Have a delta CRL with valid times */
64 #define CRL_SCORE_TIME_DELTA 0x002
66 static int build_chain(X509_STORE_CTX *ctx);
67 static int verify_chain(X509_STORE_CTX *ctx);
68 static int dane_verify(X509_STORE_CTX *ctx);
69 static int null_callback(int ok, X509_STORE_CTX *e);
70 static int check_issued(X509_STORE_CTX *ctx, X509 *x, X509 *issuer);
71 static X509 *find_issuer(X509_STORE_CTX *ctx, STACK_OF(X509) *sk, X509 *x);
72 static int check_chain_extensions(X509_STORE_CTX *ctx);
73 static int check_name_constraints(X509_STORE_CTX *ctx);
74 static int check_id(X509_STORE_CTX *ctx);
75 static int check_trust(X509_STORE_CTX *ctx, int num_untrusted);
76 static int check_revocation(X509_STORE_CTX *ctx);
77 static int check_cert(X509_STORE_CTX *ctx);
78 static int check_policy(X509_STORE_CTX *ctx);
79 static int get_issuer_sk(X509 **issuer, X509_STORE_CTX *ctx, X509 *x);
80 static int check_dane_issuer(X509_STORE_CTX *ctx, int depth);
81 static int check_key_level(X509_STORE_CTX *ctx, X509 *cert);
82 static int check_sig_level(X509_STORE_CTX *ctx, X509 *cert);
84 static int get_crl_score(X509_STORE_CTX *ctx, X509 **pissuer,
85 unsigned int *preasons, X509_CRL *crl, X509 *x);
86 static int get_crl_delta(X509_STORE_CTX *ctx,
87 X509_CRL **pcrl, X509_CRL **pdcrl, X509 *x);
88 static void get_delta_sk(X509_STORE_CTX *ctx, X509_CRL **dcrl,
89 int *pcrl_score, X509_CRL *base,
90 STACK_OF(X509_CRL) *crls);
91 static void crl_akid_check(X509_STORE_CTX *ctx, X509_CRL *crl, X509 **pissuer,
93 static int crl_crldp_check(X509 *x, X509_CRL *crl, int crl_score,
94 unsigned int *preasons);
95 static int check_crl_path(X509_STORE_CTX *ctx, X509 *x);
96 static int check_crl_chain(X509_STORE_CTX *ctx,
97 STACK_OF(X509) *cert_path,
98 STACK_OF(X509) *crl_path);
100 static int internal_verify(X509_STORE_CTX *ctx);
102 static int null_callback(int ok, X509_STORE_CTX *e)
107 /* Return 1 is a certificate is self signed */
108 static int cert_self_signed(X509 *x)
110 if (X509_check_purpose(x, -1, 0) != 1)
112 if (x->ex_flags & EXFLAG_SS)
118 /* Given a certificate try and find an exact match in the store */
120 static X509 *lookup_cert_match(X509_STORE_CTX *ctx, X509 *x)
122 STACK_OF(X509) *certs;
125 /* Lookup all certs with matching subject name */
126 certs = ctx->lookup_certs(ctx, X509_get_subject_name(x));
129 /* Look for exact match */
130 for (i = 0; i < sk_X509_num(certs); i++) {
131 xtmp = sk_X509_value(certs, i);
132 if (!X509_cmp(xtmp, x))
135 if (i < sk_X509_num(certs))
139 sk_X509_pop_free(certs, X509_free);
144 * Inform the verify callback of an error.
145 * If B<x> is not NULL it is the error cert, otherwise use the chain cert at
147 * If B<err> is not X509_V_OK, that's the error value, otherwise leave
148 * unchanged (presumably set by the caller).
150 * Returns 0 to abort verification with an error, non-zero to continue.
152 static int verify_cb_cert(X509_STORE_CTX *ctx, X509 *x, int depth, int err)
154 ctx->error_depth = depth;
155 ctx->current_cert = (x != NULL) ? x : sk_X509_value(ctx->chain, depth);
156 if (err != X509_V_OK)
158 return ctx->verify_cb(0, ctx);
162 * Inform the verify callback of an error, CRL-specific variant. Here, the
163 * error depth and certificate are already set, we just specify the error
166 * Returns 0 to abort verification with an error, non-zero to continue.
168 static int verify_cb_crl(X509_STORE_CTX *ctx, int err)
171 return ctx->verify_cb(0, ctx);
174 static int check_auth_level(X509_STORE_CTX *ctx)
177 int num = sk_X509_num(ctx->chain);
179 if (ctx->param->auth_level <= 0)
182 for (i = 0; i < num; ++i) {
183 X509 *cert = sk_X509_value(ctx->chain, i);
186 * We've already checked the security of the leaf key, so here we only
187 * check the security of issuer keys.
189 if (i > 0 && !check_key_level(ctx, cert) &&
190 verify_cb_cert(ctx, cert, i, X509_V_ERR_CA_KEY_TOO_SMALL) == 0)
193 * We also check the signature algorithm security of all certificates
194 * except those of the trust anchor at index num-1.
196 if (i < num - 1 && !check_sig_level(ctx, cert) &&
197 verify_cb_cert(ctx, cert, i, X509_V_ERR_CA_MD_TOO_WEAK) == 0)
203 static int verify_chain(X509_STORE_CTX *ctx)
209 * Before either returning with an error, or continuing with CRL checks,
210 * instantiate chain public key parameters.
212 if ((ok = build_chain(ctx)) == 0 ||
213 (ok = check_chain_extensions(ctx)) == 0 ||
214 (ok = check_auth_level(ctx)) == 0 ||
215 (ok = check_id(ctx)) == 0 || 1)
216 X509_get_pubkey_parameters(NULL, ctx->chain);
217 if (ok == 0 || (ok = ctx->check_revocation(ctx)) == 0)
220 err = X509_chain_check_suiteb(&ctx->error_depth, NULL, ctx->chain,
222 if (err != X509_V_OK) {
223 if ((ok = verify_cb_cert(ctx, NULL, ctx->error_depth, err)) == 0)
227 /* Verify chain signatures and expiration times */
228 ok = (ctx->verify != NULL) ? ctx->verify(ctx) : internal_verify(ctx);
232 if ((ok = check_name_constraints(ctx)) == 0)
235 #ifndef OPENSSL_NO_RFC3779
236 /* RFC 3779 path validation, now that CRL check has been done */
237 if ((ok = X509v3_asid_validate_path(ctx)) == 0)
239 if ((ok = X509v3_addr_validate_path(ctx)) == 0)
243 /* If we get this far evaluate policies */
244 if (ctx->param->flags & X509_V_FLAG_POLICY_CHECK)
245 ok = ctx->check_policy(ctx);
249 int X509_verify_cert(X509_STORE_CTX *ctx)
251 SSL_DANE *dane = ctx->dane;
254 if (ctx->cert == NULL) {
255 X509err(X509_F_X509_VERIFY_CERT, X509_R_NO_CERT_SET_FOR_US_TO_VERIFY);
256 ctx->error = X509_V_ERR_INVALID_CALL;
260 if (ctx->chain != NULL) {
262 * This X509_STORE_CTX has already been used to verify a cert. We
263 * cannot do another one.
265 X509err(X509_F_X509_VERIFY_CERT, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
266 ctx->error = X509_V_ERR_INVALID_CALL;
271 * first we make sure the chain we are going to build is present and that
272 * the first entry is in place
274 if (((ctx->chain = sk_X509_new_null()) == NULL) ||
275 (!sk_X509_push(ctx->chain, ctx->cert))) {
276 X509err(X509_F_X509_VERIFY_CERT, ERR_R_MALLOC_FAILURE);
277 ctx->error = X509_V_ERR_OUT_OF_MEM;
280 X509_up_ref(ctx->cert);
281 ctx->num_untrusted = 1;
283 /* If the peer's public key is too weak, we can stop early. */
284 if (!check_key_level(ctx, ctx->cert) &&
285 !verify_cb_cert(ctx, ctx->cert, 0, X509_V_ERR_EE_KEY_TOO_SMALL))
288 if (DANETLS_ENABLED(dane))
289 ret = dane_verify(ctx);
291 ret = verify_chain(ctx);
294 * Safety-net. If we are returning an error, we must also set ctx->error,
295 * so that the chain is not considered verified should the error be ignored
296 * (e.g. TLS with SSL_VERIFY_NONE).
298 if (ret <= 0 && ctx->error == X509_V_OK)
299 ctx->error = X509_V_ERR_UNSPECIFIED;
304 * Given a STACK_OF(X509) find the issuer of cert (if any)
306 static X509 *find_issuer(X509_STORE_CTX *ctx, STACK_OF(X509) *sk, X509 *x)
309 X509 *issuer, *rv = NULL;
311 for (i = 0; i < sk_X509_num(sk); i++) {
312 issuer = sk_X509_value(sk, i);
313 if (ctx->check_issued(ctx, x, issuer)) {
315 if (x509_check_cert_time(ctx, rv, -1))
322 /* Given a possible certificate and issuer check them */
324 static int check_issued(X509_STORE_CTX *ctx, X509 *x, X509 *issuer)
328 return cert_self_signed(x);
329 ret = X509_check_issued(issuer, x);
330 if (ret == X509_V_OK) {
333 /* Special case: single self signed certificate */
334 if (cert_self_signed(x) && sk_X509_num(ctx->chain) == 1)
336 for (i = 0; i < sk_X509_num(ctx->chain); i++) {
337 ch = sk_X509_value(ctx->chain, i);
338 if (ch == issuer || !X509_cmp(ch, issuer)) {
339 ret = X509_V_ERR_PATH_LOOP;
345 return (ret == X509_V_OK);
348 /* Alternative lookup method: look from a STACK stored in other_ctx */
350 static int get_issuer_sk(X509 **issuer, X509_STORE_CTX *ctx, X509 *x)
352 *issuer = find_issuer(ctx, ctx->other_ctx, x);
354 X509_up_ref(*issuer);
360 static STACK_OF(X509) *lookup_certs_sk(X509_STORE_CTX *ctx, X509_NAME *nm)
362 STACK_OF(X509) *sk = NULL;
366 for (i = 0; i < sk_X509_num(ctx->other_ctx); i++) {
367 x = sk_X509_value(ctx->other_ctx, i);
368 if (X509_NAME_cmp(nm, X509_get_subject_name(x)) == 0) {
370 sk = sk_X509_new_null();
371 if (sk == NULL || sk_X509_push(sk, x) == 0) {
372 sk_X509_pop_free(sk, X509_free);
373 X509err(X509_F_LOOKUP_CERTS_SK, ERR_R_MALLOC_FAILURE);
374 ctx->error = X509_V_ERR_OUT_OF_MEM;
384 * Check EE or CA certificate purpose. For trusted certificates explicit local
385 * auxiliary trust can be used to override EKU-restrictions.
387 static int check_purpose(X509_STORE_CTX *ctx, X509 *x, int purpose, int depth,
390 int tr_ok = X509_TRUST_UNTRUSTED;
393 * For trusted certificates we want to see whether any auxiliary trust
394 * settings trump the purpose constraints.
396 * This is complicated by the fact that the trust ordinals in
397 * ctx->param->trust are entirely independent of the purpose ordinals in
398 * ctx->param->purpose!
400 * What connects them is their mutual initialization via calls from
401 * X509_STORE_CTX_set_default() into X509_VERIFY_PARAM_lookup() which sets
402 * related values of both param->trust and param->purpose. It is however
403 * typically possible to infer associated trust values from a purpose value
404 * via the X509_PURPOSE API.
406 * Therefore, we can only check for trust overrides when the purpose we're
407 * checking is the same as ctx->param->purpose and ctx->param->trust is
410 if (depth >= ctx->num_untrusted && purpose == ctx->param->purpose)
411 tr_ok = X509_check_trust(x, ctx->param->trust, X509_TRUST_NO_SS_COMPAT);
414 case X509_TRUST_TRUSTED:
416 case X509_TRUST_REJECTED:
419 switch (X509_check_purpose(x, purpose, must_be_ca > 0)) {
425 if ((ctx->param->flags & X509_V_FLAG_X509_STRICT) == 0)
431 return verify_cb_cert(ctx, x, depth, X509_V_ERR_INVALID_PURPOSE);
435 * Check a certificate chains extensions for consistency with the supplied
439 static int check_chain_extensions(X509_STORE_CTX *ctx)
441 int i, must_be_ca, plen = 0;
443 int proxy_path_length = 0;
445 int allow_proxy_certs;
446 int num = sk_X509_num(ctx->chain);
449 * must_be_ca can have 1 of 3 values:
450 * -1: we accept both CA and non-CA certificates, to allow direct
451 * use of self-signed certificates (which are marked as CA).
452 * 0: we only accept non-CA certificates. This is currently not
453 * used, but the possibility is present for future extensions.
454 * 1: we only accept CA certificates. This is currently used for
455 * all certificates in the chain except the leaf certificate.
459 /* CRL path validation */
461 allow_proxy_certs = 0;
462 purpose = X509_PURPOSE_CRL_SIGN;
465 ! !(ctx->param->flags & X509_V_FLAG_ALLOW_PROXY_CERTS);
466 purpose = ctx->param->purpose;
469 for (i = 0; i < num; i++) {
471 x = sk_X509_value(ctx->chain, i);
472 if (!(ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL)
473 && (x->ex_flags & EXFLAG_CRITICAL)) {
474 if (!verify_cb_cert(ctx, x, i,
475 X509_V_ERR_UNHANDLED_CRITICAL_EXTENSION))
478 if (!allow_proxy_certs && (x->ex_flags & EXFLAG_PROXY)) {
479 if (!verify_cb_cert(ctx, x, i,
480 X509_V_ERR_PROXY_CERTIFICATES_NOT_ALLOWED))
483 ret = X509_check_ca(x);
484 switch (must_be_ca) {
486 if ((ctx->param->flags & X509_V_FLAG_X509_STRICT)
487 && (ret != 1) && (ret != 0)) {
489 ctx->error = X509_V_ERR_INVALID_CA;
496 ctx->error = X509_V_ERR_INVALID_NON_CA;
501 /* X509_V_FLAG_X509_STRICT is implicit for intermediate CAs */
503 || ((i + 1 < num || ctx->param->flags & X509_V_FLAG_X509_STRICT)
506 ctx->error = X509_V_ERR_INVALID_CA;
511 if ((x->ex_flags & EXFLAG_CA) == 0
512 && x->ex_pathlen != -1
513 && (ctx->param->flags & X509_V_FLAG_X509_STRICT)) {
514 ctx->error = X509_V_ERR_INVALID_EXTENSION;
517 if (ret == 0 && !verify_cb_cert(ctx, x, i, X509_V_OK))
519 /* check_purpose() makes the callback as needed */
520 if (purpose > 0 && !check_purpose(ctx, x, purpose, i, must_be_ca))
523 if ((i > 1) && (x->ex_pathlen != -1)
524 && (plen > (x->ex_pathlen + proxy_path_length))) {
525 if (!verify_cb_cert(ctx, x, i, X509_V_ERR_PATH_LENGTH_EXCEEDED))
528 /* Increment path length if not a self issued intermediate CA */
529 if (i > 0 && (x->ex_flags & EXFLAG_SI) == 0)
532 * If this certificate is a proxy certificate, the next certificate
533 * must be another proxy certificate or a EE certificate. If not,
534 * the next certificate must be a CA certificate.
536 if (x->ex_flags & EXFLAG_PROXY) {
538 * RFC3820, 4.1.3 (b)(1) stipulates that if pCPathLengthConstraint
539 * is less than max_path_length, the former should be copied to
540 * the latter, and 4.1.4 (a) stipulates that max_path_length
541 * should be verified to be larger than zero and decrement it.
543 * Because we're checking the certs in the reverse order, we start
544 * with verifying that proxy_path_length isn't larger than pcPLC,
545 * and copy the latter to the former if it is, and finally,
546 * increment proxy_path_length.
548 if (x->ex_pcpathlen != -1) {
549 if (proxy_path_length > x->ex_pcpathlen) {
550 if (!verify_cb_cert(ctx, x, i,
551 X509_V_ERR_PROXY_PATH_LENGTH_EXCEEDED))
554 proxy_path_length = x->ex_pcpathlen;
564 static int has_san_id(X509 *x, int gtype)
568 GENERAL_NAMES *gs = X509_get_ext_d2i(x, NID_subject_alt_name, NULL, NULL);
573 for (i = 0; i < sk_GENERAL_NAME_num(gs); i++) {
574 GENERAL_NAME *g = sk_GENERAL_NAME_value(gs, i);
576 if (g->type == gtype) {
581 GENERAL_NAMES_free(gs);
585 static int check_name_constraints(X509_STORE_CTX *ctx)
589 /* Check name constraints for all certificates */
590 for (i = sk_X509_num(ctx->chain) - 1; i >= 0; i--) {
591 X509 *x = sk_X509_value(ctx->chain, i);
594 /* Ignore self issued certs unless last in chain */
595 if (i && (x->ex_flags & EXFLAG_SI))
599 * Proxy certificates policy has an extra constraint, where the
600 * certificate subject MUST be the issuer with a single CN entry
602 * (RFC 3820: 3.4, 4.1.3 (a)(4))
604 if (x->ex_flags & EXFLAG_PROXY) {
605 X509_NAME *tmpsubject = X509_get_subject_name(x);
606 X509_NAME *tmpissuer = X509_get_issuer_name(x);
607 X509_NAME_ENTRY *tmpentry = NULL;
608 int last_object_nid = 0;
610 int last_object_loc = X509_NAME_entry_count(tmpsubject) - 1;
612 /* Check that there are at least two RDNs */
613 if (last_object_loc < 1) {
614 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
615 goto proxy_name_done;
619 * Check that there is exactly one more RDN in subject as
620 * there is in issuer.
622 if (X509_NAME_entry_count(tmpsubject)
623 != X509_NAME_entry_count(tmpissuer) + 1) {
624 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
625 goto proxy_name_done;
629 * Check that the last subject component isn't part of a
632 if (X509_NAME_ENTRY_set(X509_NAME_get_entry(tmpsubject,
634 == X509_NAME_ENTRY_set(X509_NAME_get_entry(tmpsubject,
635 last_object_loc - 1))) {
636 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
637 goto proxy_name_done;
641 * Check that the last subject RDN is a commonName, and that
642 * all the previous RDNs match the issuer exactly
644 tmpsubject = X509_NAME_dup(tmpsubject);
645 if (tmpsubject == NULL) {
646 X509err(X509_F_CHECK_NAME_CONSTRAINTS, ERR_R_MALLOC_FAILURE);
647 ctx->error = X509_V_ERR_OUT_OF_MEM;
652 X509_NAME_delete_entry(tmpsubject, last_object_loc);
654 OBJ_obj2nid(X509_NAME_ENTRY_get_object(tmpentry));
656 if (last_object_nid != NID_commonName
657 || X509_NAME_cmp(tmpsubject, tmpissuer) != 0) {
658 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
661 X509_NAME_ENTRY_free(tmpentry);
662 X509_NAME_free(tmpsubject);
666 && !verify_cb_cert(ctx, x, i, err))
671 * Check against constraints for all certificates higher in chain
672 * including trust anchor. Trust anchor not strictly speaking needed
673 * but if it includes constraints it is to be assumed it expects them
676 for (j = sk_X509_num(ctx->chain) - 1; j > i; j--) {
677 NAME_CONSTRAINTS *nc = sk_X509_value(ctx->chain, j)->nc;
680 int rv = NAME_CONSTRAINTS_check(x, nc);
682 /* If EE certificate check commonName too */
683 if (rv == X509_V_OK && i == 0
684 && (ctx->param->hostflags
685 & X509_CHECK_FLAG_NEVER_CHECK_SUBJECT) == 0
686 && ((ctx->param->hostflags
687 & X509_CHECK_FLAG_ALWAYS_CHECK_SUBJECT) != 0
688 || !has_san_id(x, GEN_DNS)))
689 rv = NAME_CONSTRAINTS_check_CN(x, nc);
694 case X509_V_ERR_OUT_OF_MEM:
697 if (!verify_cb_cert(ctx, x, i, rv))
707 static int check_id_error(X509_STORE_CTX *ctx, int errcode)
709 return verify_cb_cert(ctx, ctx->cert, 0, errcode);
712 static int check_hosts(X509 *x, X509_VERIFY_PARAM *vpm)
715 int n = sk_OPENSSL_STRING_num(vpm->hosts);
718 if (vpm->peername != NULL) {
719 OPENSSL_free(vpm->peername);
720 vpm->peername = NULL;
722 for (i = 0; i < n; ++i) {
723 name = sk_OPENSSL_STRING_value(vpm->hosts, i);
724 if (X509_check_host(x, name, 0, vpm->hostflags, &vpm->peername) > 0)
730 static int check_id(X509_STORE_CTX *ctx)
732 X509_VERIFY_PARAM *vpm = ctx->param;
734 if (vpm->hosts && check_hosts(x, vpm) <= 0) {
735 if (!check_id_error(ctx, X509_V_ERR_HOSTNAME_MISMATCH))
738 if (vpm->email && X509_check_email(x, vpm->email, vpm->emaillen, 0) <= 0) {
739 if (!check_id_error(ctx, X509_V_ERR_EMAIL_MISMATCH))
742 if (vpm->ip && X509_check_ip(x, vpm->ip, vpm->iplen, 0) <= 0) {
743 if (!check_id_error(ctx, X509_V_ERR_IP_ADDRESS_MISMATCH))
749 static int check_trust(X509_STORE_CTX *ctx, int num_untrusted)
754 SSL_DANE *dane = ctx->dane;
755 int num = sk_X509_num(ctx->chain);
759 * Check for a DANE issuer at depth 1 or greater, if it is a DANE-TA(2)
760 * match, we're done, otherwise we'll merely record the match depth.
762 if (DANETLS_HAS_TA(dane) && num_untrusted > 0 && num_untrusted < num) {
763 switch (trust = check_dane_issuer(ctx, num_untrusted)) {
764 case X509_TRUST_TRUSTED:
765 case X509_TRUST_REJECTED:
771 * Check trusted certificates in chain at depth num_untrusted and up.
772 * Note, that depths 0..num_untrusted-1 may also contain trusted
773 * certificates, but the caller is expected to have already checked those,
774 * and wants to incrementally check just any added since.
776 for (i = num_untrusted; i < num; i++) {
777 x = sk_X509_value(ctx->chain, i);
778 trust = X509_check_trust(x, ctx->param->trust, 0);
779 /* If explicitly trusted return trusted */
780 if (trust == X509_TRUST_TRUSTED)
782 if (trust == X509_TRUST_REJECTED)
787 * If we are looking at a trusted certificate, and accept partial chains,
788 * the chain is PKIX trusted.
790 if (num_untrusted < num) {
791 if (ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN)
793 return X509_TRUST_UNTRUSTED;
796 if (num_untrusted == num && ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) {
798 * Last-resort call with no new trusted certificates, check the leaf
799 * for a direct trust store match.
802 x = sk_X509_value(ctx->chain, i);
803 mx = lookup_cert_match(ctx, x);
805 return X509_TRUST_UNTRUSTED;
808 * Check explicit auxiliary trust/reject settings. If none are set,
809 * we'll accept X509_TRUST_UNTRUSTED when not self-signed.
811 trust = X509_check_trust(mx, ctx->param->trust, 0);
812 if (trust == X509_TRUST_REJECTED) {
817 /* Replace leaf with trusted match */
818 (void) sk_X509_set(ctx->chain, 0, mx);
820 ctx->num_untrusted = 0;
825 * If no trusted certs in chain at all return untrusted and allow
826 * standard (no issuer cert) etc errors to be indicated.
828 return X509_TRUST_UNTRUSTED;
831 if (!verify_cb_cert(ctx, x, i, X509_V_ERR_CERT_REJECTED))
832 return X509_TRUST_REJECTED;
833 return X509_TRUST_UNTRUSTED;
836 if (!DANETLS_ENABLED(dane))
837 return X509_TRUST_TRUSTED;
839 dane->pdpth = num_untrusted;
840 /* With DANE, PKIX alone is not trusted until we have both */
841 if (dane->mdpth >= 0)
842 return X509_TRUST_TRUSTED;
843 return X509_TRUST_UNTRUSTED;
846 static int check_revocation(X509_STORE_CTX *ctx)
848 int i = 0, last = 0, ok = 0;
849 if (!(ctx->param->flags & X509_V_FLAG_CRL_CHECK))
851 if (ctx->param->flags & X509_V_FLAG_CRL_CHECK_ALL)
852 last = sk_X509_num(ctx->chain) - 1;
854 /* If checking CRL paths this isn't the EE certificate */
859 for (i = 0; i <= last; i++) {
860 ctx->error_depth = i;
861 ok = check_cert(ctx);
868 static int check_cert(X509_STORE_CTX *ctx)
870 X509_CRL *crl = NULL, *dcrl = NULL;
872 int cnum = ctx->error_depth;
873 X509 *x = sk_X509_value(ctx->chain, cnum);
875 ctx->current_cert = x;
876 ctx->current_issuer = NULL;
877 ctx->current_crl_score = 0;
878 ctx->current_reasons = 0;
880 if (x->ex_flags & EXFLAG_PROXY)
883 while (ctx->current_reasons != CRLDP_ALL_REASONS) {
884 unsigned int last_reasons = ctx->current_reasons;
886 /* Try to retrieve relevant CRL */
888 ok = ctx->get_crl(ctx, &crl, x);
890 ok = get_crl_delta(ctx, &crl, &dcrl, x);
892 * If error looking up CRL, nothing we can do except notify callback
895 ok = verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL);
898 ctx->current_crl = crl;
899 ok = ctx->check_crl(ctx, crl);
904 ok = ctx->check_crl(ctx, dcrl);
907 ok = ctx->cert_crl(ctx, dcrl, x);
913 /* Don't look in full CRL if delta reason is removefromCRL */
915 ok = ctx->cert_crl(ctx, crl, x);
925 * If reasons not updated we won't get anywhere by another iteration,
928 if (last_reasons == ctx->current_reasons) {
929 ok = verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL);
937 ctx->current_crl = NULL;
941 /* Check CRL times against values in X509_STORE_CTX */
943 static int check_crl_time(X509_STORE_CTX *ctx, X509_CRL *crl, int notify)
949 ctx->current_crl = crl;
950 if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME)
951 ptime = &ctx->param->check_time;
952 else if (ctx->param->flags & X509_V_FLAG_NO_CHECK_TIME)
957 i = X509_cmp_time(X509_CRL_get0_lastUpdate(crl), ptime);
961 if (!verify_cb_crl(ctx, X509_V_ERR_ERROR_IN_CRL_LAST_UPDATE_FIELD))
968 if (!verify_cb_crl(ctx, X509_V_ERR_CRL_NOT_YET_VALID))
972 if (X509_CRL_get0_nextUpdate(crl)) {
973 i = X509_cmp_time(X509_CRL_get0_nextUpdate(crl), ptime);
978 if (!verify_cb_crl(ctx, X509_V_ERR_ERROR_IN_CRL_NEXT_UPDATE_FIELD))
981 /* Ignore expiry of base CRL is delta is valid */
982 if ((i < 0) && !(ctx->current_crl_score & CRL_SCORE_TIME_DELTA)) {
985 if (!verify_cb_crl(ctx, X509_V_ERR_CRL_HAS_EXPIRED))
991 ctx->current_crl = NULL;
996 static int get_crl_sk(X509_STORE_CTX *ctx, X509_CRL **pcrl, X509_CRL **pdcrl,
997 X509 **pissuer, int *pscore, unsigned int *preasons,
998 STACK_OF(X509_CRL) *crls)
1000 int i, crl_score, best_score = *pscore;
1001 unsigned int reasons, best_reasons = 0;
1002 X509 *x = ctx->current_cert;
1003 X509_CRL *crl, *best_crl = NULL;
1004 X509 *crl_issuer = NULL, *best_crl_issuer = NULL;
1006 for (i = 0; i < sk_X509_CRL_num(crls); i++) {
1007 crl = sk_X509_CRL_value(crls, i);
1008 reasons = *preasons;
1009 crl_score = get_crl_score(ctx, &crl_issuer, &reasons, crl, x);
1010 if (crl_score < best_score || crl_score == 0)
1012 /* If current CRL is equivalent use it if it is newer */
1013 if (crl_score == best_score && best_crl != NULL) {
1015 if (ASN1_TIME_diff(&day, &sec, X509_CRL_get0_lastUpdate(best_crl),
1016 X509_CRL_get0_lastUpdate(crl)) == 0)
1019 * ASN1_TIME_diff never returns inconsistent signs for |day|
1022 if (day <= 0 && sec <= 0)
1026 best_crl_issuer = crl_issuer;
1027 best_score = crl_score;
1028 best_reasons = reasons;
1032 X509_CRL_free(*pcrl);
1034 *pissuer = best_crl_issuer;
1035 *pscore = best_score;
1036 *preasons = best_reasons;
1037 X509_CRL_up_ref(best_crl);
1038 X509_CRL_free(*pdcrl);
1040 get_delta_sk(ctx, pdcrl, pscore, best_crl, crls);
1043 if (best_score >= CRL_SCORE_VALID)
1050 * Compare two CRL extensions for delta checking purposes. They should be
1051 * both present or both absent. If both present all fields must be identical.
1054 static int crl_extension_match(X509_CRL *a, X509_CRL *b, int nid)
1056 ASN1_OCTET_STRING *exta, *extb;
1058 i = X509_CRL_get_ext_by_NID(a, nid, -1);
1060 /* Can't have multiple occurrences */
1061 if (X509_CRL_get_ext_by_NID(a, nid, i) != -1)
1063 exta = X509_EXTENSION_get_data(X509_CRL_get_ext(a, i));
1067 i = X509_CRL_get_ext_by_NID(b, nid, -1);
1071 if (X509_CRL_get_ext_by_NID(b, nid, i) != -1)
1073 extb = X509_EXTENSION_get_data(X509_CRL_get_ext(b, i));
1083 if (ASN1_OCTET_STRING_cmp(exta, extb))
1089 /* See if a base and delta are compatible */
1091 static int check_delta_base(X509_CRL *delta, X509_CRL *base)
1093 /* Delta CRL must be a delta */
1094 if (!delta->base_crl_number)
1096 /* Base must have a CRL number */
1097 if (!base->crl_number)
1099 /* Issuer names must match */
1100 if (X509_NAME_cmp(X509_CRL_get_issuer(base), X509_CRL_get_issuer(delta)))
1102 /* AKID and IDP must match */
1103 if (!crl_extension_match(delta, base, NID_authority_key_identifier))
1105 if (!crl_extension_match(delta, base, NID_issuing_distribution_point))
1107 /* Delta CRL base number must not exceed Full CRL number. */
1108 if (ASN1_INTEGER_cmp(delta->base_crl_number, base->crl_number) > 0)
1110 /* Delta CRL number must exceed full CRL number */
1111 if (ASN1_INTEGER_cmp(delta->crl_number, base->crl_number) > 0)
1117 * For a given base CRL find a delta... maybe extend to delta scoring or
1118 * retrieve a chain of deltas...
1121 static void get_delta_sk(X509_STORE_CTX *ctx, X509_CRL **dcrl, int *pscore,
1122 X509_CRL *base, STACK_OF(X509_CRL) *crls)
1126 if (!(ctx->param->flags & X509_V_FLAG_USE_DELTAS))
1128 if (!((ctx->current_cert->ex_flags | base->flags) & EXFLAG_FRESHEST))
1130 for (i = 0; i < sk_X509_CRL_num(crls); i++) {
1131 delta = sk_X509_CRL_value(crls, i);
1132 if (check_delta_base(delta, base)) {
1133 if (check_crl_time(ctx, delta, 0))
1134 *pscore |= CRL_SCORE_TIME_DELTA;
1135 X509_CRL_up_ref(delta);
1144 * For a given CRL return how suitable it is for the supplied certificate
1145 * 'x'. The return value is a mask of several criteria. If the issuer is not
1146 * the certificate issuer this is returned in *pissuer. The reasons mask is
1147 * also used to determine if the CRL is suitable: if no new reasons the CRL
1148 * is rejected, otherwise reasons is updated.
1151 static int get_crl_score(X509_STORE_CTX *ctx, X509 **pissuer,
1152 unsigned int *preasons, X509_CRL *crl, X509 *x)
1156 unsigned int tmp_reasons = *preasons, crl_reasons;
1158 /* First see if we can reject CRL straight away */
1160 /* Invalid IDP cannot be processed */
1161 if (crl->idp_flags & IDP_INVALID)
1163 /* Reason codes or indirect CRLs need extended CRL support */
1164 if (!(ctx->param->flags & X509_V_FLAG_EXTENDED_CRL_SUPPORT)) {
1165 if (crl->idp_flags & (IDP_INDIRECT | IDP_REASONS))
1167 } else if (crl->idp_flags & IDP_REASONS) {
1168 /* If no new reasons reject */
1169 if (!(crl->idp_reasons & ~tmp_reasons))
1172 /* Don't process deltas at this stage */
1173 else if (crl->base_crl_number)
1175 /* If issuer name doesn't match certificate need indirect CRL */
1176 if (X509_NAME_cmp(X509_get_issuer_name(x), X509_CRL_get_issuer(crl))) {
1177 if (!(crl->idp_flags & IDP_INDIRECT))
1180 crl_score |= CRL_SCORE_ISSUER_NAME;
1182 if (!(crl->flags & EXFLAG_CRITICAL))
1183 crl_score |= CRL_SCORE_NOCRITICAL;
1186 if (check_crl_time(ctx, crl, 0))
1187 crl_score |= CRL_SCORE_TIME;
1189 /* Check authority key ID and locate certificate issuer */
1190 crl_akid_check(ctx, crl, pissuer, &crl_score);
1192 /* If we can't locate certificate issuer at this point forget it */
1194 if (!(crl_score & CRL_SCORE_AKID))
1197 /* Check cert for matching CRL distribution points */
1199 if (crl_crldp_check(x, crl, crl_score, &crl_reasons)) {
1200 /* If no new reasons reject */
1201 if (!(crl_reasons & ~tmp_reasons))
1203 tmp_reasons |= crl_reasons;
1204 crl_score |= CRL_SCORE_SCOPE;
1207 *preasons = tmp_reasons;
1213 static void crl_akid_check(X509_STORE_CTX *ctx, X509_CRL *crl,
1214 X509 **pissuer, int *pcrl_score)
1216 X509 *crl_issuer = NULL;
1217 X509_NAME *cnm = X509_CRL_get_issuer(crl);
1218 int cidx = ctx->error_depth;
1221 if (cidx != sk_X509_num(ctx->chain) - 1)
1224 crl_issuer = sk_X509_value(ctx->chain, cidx);
1226 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1227 if (*pcrl_score & CRL_SCORE_ISSUER_NAME) {
1228 *pcrl_score |= CRL_SCORE_AKID | CRL_SCORE_ISSUER_CERT;
1229 *pissuer = crl_issuer;
1234 for (cidx++; cidx < sk_X509_num(ctx->chain); cidx++) {
1235 crl_issuer = sk_X509_value(ctx->chain, cidx);
1236 if (X509_NAME_cmp(X509_get_subject_name(crl_issuer), cnm))
1238 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1239 *pcrl_score |= CRL_SCORE_AKID | CRL_SCORE_SAME_PATH;
1240 *pissuer = crl_issuer;
1245 /* Anything else needs extended CRL support */
1247 if (!(ctx->param->flags & X509_V_FLAG_EXTENDED_CRL_SUPPORT))
1251 * Otherwise the CRL issuer is not on the path. Look for it in the set of
1252 * untrusted certificates.
1254 for (i = 0; i < sk_X509_num(ctx->untrusted); i++) {
1255 crl_issuer = sk_X509_value(ctx->untrusted, i);
1256 if (X509_NAME_cmp(X509_get_subject_name(crl_issuer), cnm))
1258 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1259 *pissuer = crl_issuer;
1260 *pcrl_score |= CRL_SCORE_AKID;
1267 * Check the path of a CRL issuer certificate. This creates a new
1268 * X509_STORE_CTX and populates it with most of the parameters from the
1269 * parent. This could be optimised somewhat since a lot of path checking will
1270 * be duplicated by the parent, but this will rarely be used in practice.
1273 static int check_crl_path(X509_STORE_CTX *ctx, X509 *x)
1275 X509_STORE_CTX crl_ctx;
1278 /* Don't allow recursive CRL path validation */
1281 if (!X509_STORE_CTX_init(&crl_ctx, ctx->ctx, x, ctx->untrusted))
1284 crl_ctx.crls = ctx->crls;
1285 /* Copy verify params across */
1286 X509_STORE_CTX_set0_param(&crl_ctx, ctx->param);
1288 crl_ctx.parent = ctx;
1289 crl_ctx.verify_cb = ctx->verify_cb;
1291 /* Verify CRL issuer */
1292 ret = X509_verify_cert(&crl_ctx);
1296 /* Check chain is acceptable */
1297 ret = check_crl_chain(ctx, ctx->chain, crl_ctx.chain);
1299 X509_STORE_CTX_cleanup(&crl_ctx);
1304 * RFC3280 says nothing about the relationship between CRL path and
1305 * certificate path, which could lead to situations where a certificate could
1306 * be revoked or validated by a CA not authorised to do so. RFC5280 is more
1307 * strict and states that the two paths must end in the same trust anchor,
1308 * though some discussions remain... until this is resolved we use the
1312 static int check_crl_chain(X509_STORE_CTX *ctx,
1313 STACK_OF(X509) *cert_path,
1314 STACK_OF(X509) *crl_path)
1316 X509 *cert_ta, *crl_ta;
1317 cert_ta = sk_X509_value(cert_path, sk_X509_num(cert_path) - 1);
1318 crl_ta = sk_X509_value(crl_path, sk_X509_num(crl_path) - 1);
1319 if (!X509_cmp(cert_ta, crl_ta))
1325 * Check for match between two dist point names: three separate cases.
1326 * 1. Both are relative names and compare X509_NAME types.
1327 * 2. One full, one relative. Compare X509_NAME to GENERAL_NAMES.
1328 * 3. Both are full names and compare two GENERAL_NAMES.
1329 * 4. One is NULL: automatic match.
1332 static int idp_check_dp(DIST_POINT_NAME *a, DIST_POINT_NAME *b)
1334 X509_NAME *nm = NULL;
1335 GENERAL_NAMES *gens = NULL;
1336 GENERAL_NAME *gena, *genb;
1343 /* Case 1: two X509_NAME */
1347 if (!X509_NAME_cmp(a->dpname, b->dpname))
1352 /* Case 2: set name and GENERAL_NAMES appropriately */
1354 gens = b->name.fullname;
1355 } else if (b->type == 1) {
1358 /* Case 2: set name and GENERAL_NAMES appropriately */
1359 gens = a->name.fullname;
1363 /* Handle case 2 with one GENERAL_NAMES and one X509_NAME */
1365 for (i = 0; i < sk_GENERAL_NAME_num(gens); i++) {
1366 gena = sk_GENERAL_NAME_value(gens, i);
1367 if (gena->type != GEN_DIRNAME)
1369 if (!X509_NAME_cmp(nm, gena->d.directoryName))
1375 /* Else case 3: two GENERAL_NAMES */
1377 for (i = 0; i < sk_GENERAL_NAME_num(a->name.fullname); i++) {
1378 gena = sk_GENERAL_NAME_value(a->name.fullname, i);
1379 for (j = 0; j < sk_GENERAL_NAME_num(b->name.fullname); j++) {
1380 genb = sk_GENERAL_NAME_value(b->name.fullname, j);
1381 if (!GENERAL_NAME_cmp(gena, genb))
1390 static int crldp_check_crlissuer(DIST_POINT *dp, X509_CRL *crl, int crl_score)
1393 X509_NAME *nm = X509_CRL_get_issuer(crl);
1394 /* If no CRLissuer return is successful iff don't need a match */
1396 return ! !(crl_score & CRL_SCORE_ISSUER_NAME);
1397 for (i = 0; i < sk_GENERAL_NAME_num(dp->CRLissuer); i++) {
1398 GENERAL_NAME *gen = sk_GENERAL_NAME_value(dp->CRLissuer, i);
1399 if (gen->type != GEN_DIRNAME)
1401 if (!X509_NAME_cmp(gen->d.directoryName, nm))
1407 /* Check CRLDP and IDP */
1409 static int crl_crldp_check(X509 *x, X509_CRL *crl, int crl_score,
1410 unsigned int *preasons)
1413 if (crl->idp_flags & IDP_ONLYATTR)
1415 if (x->ex_flags & EXFLAG_CA) {
1416 if (crl->idp_flags & IDP_ONLYUSER)
1419 if (crl->idp_flags & IDP_ONLYCA)
1422 *preasons = crl->idp_reasons;
1423 for (i = 0; i < sk_DIST_POINT_num(x->crldp); i++) {
1424 DIST_POINT *dp = sk_DIST_POINT_value(x->crldp, i);
1425 if (crldp_check_crlissuer(dp, crl, crl_score)) {
1426 if (!crl->idp || idp_check_dp(dp->distpoint, crl->idp->distpoint)) {
1427 *preasons &= dp->dp_reasons;
1432 if ((!crl->idp || !crl->idp->distpoint)
1433 && (crl_score & CRL_SCORE_ISSUER_NAME))
1439 * Retrieve CRL corresponding to current certificate. If deltas enabled try
1440 * to find a delta CRL too
1443 static int get_crl_delta(X509_STORE_CTX *ctx,
1444 X509_CRL **pcrl, X509_CRL **pdcrl, X509 *x)
1447 X509 *issuer = NULL;
1449 unsigned int reasons;
1450 X509_CRL *crl = NULL, *dcrl = NULL;
1451 STACK_OF(X509_CRL) *skcrl;
1452 X509_NAME *nm = X509_get_issuer_name(x);
1454 reasons = ctx->current_reasons;
1455 ok = get_crl_sk(ctx, &crl, &dcrl,
1456 &issuer, &crl_score, &reasons, ctx->crls);
1460 /* Lookup CRLs from store */
1462 skcrl = ctx->lookup_crls(ctx, nm);
1464 /* If no CRLs found and a near match from get_crl_sk use that */
1468 get_crl_sk(ctx, &crl, &dcrl, &issuer, &crl_score, &reasons, skcrl);
1470 sk_X509_CRL_pop_free(skcrl, X509_CRL_free);
1473 /* If we got any kind of CRL use it and return success */
1475 ctx->current_issuer = issuer;
1476 ctx->current_crl_score = crl_score;
1477 ctx->current_reasons = reasons;
1485 /* Check CRL validity */
1486 static int check_crl(X509_STORE_CTX *ctx, X509_CRL *crl)
1488 X509 *issuer = NULL;
1489 EVP_PKEY *ikey = NULL;
1490 int cnum = ctx->error_depth;
1491 int chnum = sk_X509_num(ctx->chain) - 1;
1493 /* if we have an alternative CRL issuer cert use that */
1494 if (ctx->current_issuer)
1495 issuer = ctx->current_issuer;
1497 * Else find CRL issuer: if not last certificate then issuer is next
1498 * certificate in chain.
1500 else if (cnum < chnum)
1501 issuer = sk_X509_value(ctx->chain, cnum + 1);
1503 issuer = sk_X509_value(ctx->chain, chnum);
1504 /* If not self signed, can't check signature */
1505 if (!ctx->check_issued(ctx, issuer, issuer) &&
1506 !verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL_ISSUER))
1514 * Skip most tests for deltas because they have already been done
1516 if (!crl->base_crl_number) {
1517 /* Check for cRLSign bit if keyUsage present */
1518 if ((issuer->ex_flags & EXFLAG_KUSAGE) &&
1519 !(issuer->ex_kusage & KU_CRL_SIGN) &&
1520 !verify_cb_crl(ctx, X509_V_ERR_KEYUSAGE_NO_CRL_SIGN))
1523 if (!(ctx->current_crl_score & CRL_SCORE_SCOPE) &&
1524 !verify_cb_crl(ctx, X509_V_ERR_DIFFERENT_CRL_SCOPE))
1527 if (!(ctx->current_crl_score & CRL_SCORE_SAME_PATH) &&
1528 check_crl_path(ctx, ctx->current_issuer) <= 0 &&
1529 !verify_cb_crl(ctx, X509_V_ERR_CRL_PATH_VALIDATION_ERROR))
1532 if ((crl->idp_flags & IDP_INVALID) &&
1533 !verify_cb_crl(ctx, X509_V_ERR_INVALID_EXTENSION))
1537 if (!(ctx->current_crl_score & CRL_SCORE_TIME) &&
1538 !check_crl_time(ctx, crl, 1))
1541 /* Attempt to get issuer certificate public key */
1542 ikey = X509_get0_pubkey(issuer);
1545 !verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY))
1549 int rv = X509_CRL_check_suiteb(crl, ikey, ctx->param->flags);
1551 if (rv != X509_V_OK && !verify_cb_crl(ctx, rv))
1553 /* Verify CRL signature */
1554 if (X509_CRL_verify(crl, ikey) <= 0 &&
1555 !verify_cb_crl(ctx, X509_V_ERR_CRL_SIGNATURE_FAILURE))
1561 /* Check certificate against CRL */
1562 static int cert_crl(X509_STORE_CTX *ctx, X509_CRL *crl, X509 *x)
1567 * The rules changed for this... previously if a CRL contained unhandled
1568 * critical extensions it could still be used to indicate a certificate
1569 * was revoked. This has since been changed since critical extensions can
1570 * change the meaning of CRL entries.
1572 if (!(ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL)
1573 && (crl->flags & EXFLAG_CRITICAL) &&
1574 !verify_cb_crl(ctx, X509_V_ERR_UNHANDLED_CRITICAL_CRL_EXTENSION))
1577 * Look for serial number of certificate in CRL. If found, make sure
1578 * reason is not removeFromCRL.
1580 if (X509_CRL_get0_by_cert(crl, &rev, x)) {
1581 if (rev->reason == CRL_REASON_REMOVE_FROM_CRL)
1583 if (!verify_cb_crl(ctx, X509_V_ERR_CERT_REVOKED))
1590 static int check_policy(X509_STORE_CTX *ctx)
1597 * With DANE, the trust anchor might be a bare public key, not a
1598 * certificate! In that case our chain does not have the trust anchor
1599 * certificate as a top-most element. This comports well with RFC5280
1600 * chain verification, since there too, the trust anchor is not part of the
1601 * chain to be verified. In particular, X509_policy_check() does not look
1602 * at the TA cert, but assumes that it is present as the top-most chain
1603 * element. We therefore temporarily push a NULL cert onto the chain if it
1604 * was verified via a bare public key, and pop it off right after the
1605 * X509_policy_check() call.
1607 if (ctx->bare_ta_signed && !sk_X509_push(ctx->chain, NULL)) {
1608 X509err(X509_F_CHECK_POLICY, ERR_R_MALLOC_FAILURE);
1609 ctx->error = X509_V_ERR_OUT_OF_MEM;
1612 ret = X509_policy_check(&ctx->tree, &ctx->explicit_policy, ctx->chain,
1613 ctx->param->policies, ctx->param->flags);
1614 if (ctx->bare_ta_signed)
1615 sk_X509_pop(ctx->chain);
1617 if (ret == X509_PCY_TREE_INTERNAL) {
1618 X509err(X509_F_CHECK_POLICY, ERR_R_MALLOC_FAILURE);
1619 ctx->error = X509_V_ERR_OUT_OF_MEM;
1622 /* Invalid or inconsistent extensions */
1623 if (ret == X509_PCY_TREE_INVALID) {
1626 /* Locate certificates with bad extensions and notify callback. */
1627 for (i = 1; i < sk_X509_num(ctx->chain); i++) {
1628 X509 *x = sk_X509_value(ctx->chain, i);
1630 if (!(x->ex_flags & EXFLAG_INVALID_POLICY))
1632 if (!verify_cb_cert(ctx, x, i,
1633 X509_V_ERR_INVALID_POLICY_EXTENSION))
1638 if (ret == X509_PCY_TREE_FAILURE) {
1639 ctx->current_cert = NULL;
1640 ctx->error = X509_V_ERR_NO_EXPLICIT_POLICY;
1641 return ctx->verify_cb(0, ctx);
1643 if (ret != X509_PCY_TREE_VALID) {
1644 X509err(X509_F_CHECK_POLICY, ERR_R_INTERNAL_ERROR);
1648 if (ctx->param->flags & X509_V_FLAG_NOTIFY_POLICY) {
1649 ctx->current_cert = NULL;
1651 * Verification errors need to be "sticky", a callback may have allowed
1652 * an SSL handshake to continue despite an error, and we must then
1653 * remain in an error state. Therefore, we MUST NOT clear earlier
1654 * verification errors by setting the error to X509_V_OK.
1656 if (!ctx->verify_cb(2, ctx))
1664 * Check certificate validity times.
1665 * If depth >= 0, invoke verification callbacks on error, otherwise just return
1666 * the validation status.
1668 * Return 1 on success, 0 otherwise.
1670 int x509_check_cert_time(X509_STORE_CTX *ctx, X509 *x, int depth)
1675 if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME)
1676 ptime = &ctx->param->check_time;
1677 else if (ctx->param->flags & X509_V_FLAG_NO_CHECK_TIME)
1682 i = X509_cmp_time(X509_get0_notBefore(x), ptime);
1683 if (i >= 0 && depth < 0)
1685 if (i == 0 && !verify_cb_cert(ctx, x, depth,
1686 X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD))
1688 if (i > 0 && !verify_cb_cert(ctx, x, depth, X509_V_ERR_CERT_NOT_YET_VALID))
1691 i = X509_cmp_time(X509_get0_notAfter(x), ptime);
1692 if (i <= 0 && depth < 0)
1694 if (i == 0 && !verify_cb_cert(ctx, x, depth,
1695 X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD))
1697 if (i < 0 && !verify_cb_cert(ctx, x, depth, X509_V_ERR_CERT_HAS_EXPIRED))
1702 static int internal_verify(X509_STORE_CTX *ctx)
1704 int n = sk_X509_num(ctx->chain) - 1;
1705 X509 *xi = sk_X509_value(ctx->chain, n);
1709 * With DANE-verified bare public key TA signatures, it remains only to
1710 * check the timestamps of the top certificate. We report the issuer as
1711 * NULL, since all we have is a bare key.
1713 if (ctx->bare_ta_signed) {
1719 if (ctx->check_issued(ctx, xi, xi))
1722 if (ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) {
1727 return verify_cb_cert(ctx, xi, 0,
1728 X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE);
1730 ctx->error_depth = n;
1731 xs = sk_X509_value(ctx->chain, n);
1735 * Do not clear ctx->error=0, it must be "sticky", only the user's callback
1736 * is allowed to reset errors (at its own peril).
1742 * Skip signature check for self signed certificates unless explicitly
1743 * asked for. It doesn't add any security and just wastes time. If
1744 * the issuer's public key is unusable, report the issuer certificate
1745 * and its depth (rather than the depth of the subject).
1747 if (xs != xi || (ctx->param->flags & X509_V_FLAG_CHECK_SS_SIGNATURE)) {
1748 if ((pkey = X509_get0_pubkey(xi)) == NULL) {
1749 if (!verify_cb_cert(ctx, xi, xi != xs ? n+1 : n,
1750 X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY))
1752 } else if (X509_verify(xs, pkey) <= 0) {
1753 if (!verify_cb_cert(ctx, xs, n,
1754 X509_V_ERR_CERT_SIGNATURE_FAILURE))
1760 /* Calls verify callback as needed */
1761 if (!x509_check_cert_time(ctx, xs, n))
1765 * Signal success at this depth. However, the previous error (if any)
1768 ctx->current_issuer = xi;
1769 ctx->current_cert = xs;
1770 ctx->error_depth = n;
1771 if (!ctx->verify_cb(1, ctx))
1776 xs = sk_X509_value(ctx->chain, n);
1782 int X509_cmp_current_time(const ASN1_TIME *ctm)
1784 return X509_cmp_time(ctm, NULL);
1787 int X509_cmp_time(const ASN1_TIME *ctm, time_t *cmp_time)
1789 static const size_t utctime_length = sizeof("YYMMDDHHMMSSZ") - 1;
1790 static const size_t generalizedtime_length = sizeof("YYYYMMDDHHMMSSZ") - 1;
1791 ASN1_TIME *asn1_cmp_time = NULL;
1792 int i, day, sec, ret = 0;
1793 #ifdef CHARSET_EBCDIC
1794 const char upper_z = 0x5A;
1796 const char upper_z = 'Z';
1799 * Note that ASN.1 allows much more slack in the time format than RFC5280.
1800 * In RFC5280, the representation is fixed:
1801 * UTCTime: YYMMDDHHMMSSZ
1802 * GeneralizedTime: YYYYMMDDHHMMSSZ
1804 * We do NOT currently enforce the following RFC 5280 requirement:
1805 * "CAs conforming to this profile MUST always encode certificate
1806 * validity dates through the year 2049 as UTCTime; certificate validity
1807 * dates in 2050 or later MUST be encoded as GeneralizedTime."
1809 switch (ctm->type) {
1810 case V_ASN1_UTCTIME:
1811 if (ctm->length != (int)(utctime_length))
1814 case V_ASN1_GENERALIZEDTIME:
1815 if (ctm->length != (int)(generalizedtime_length))
1823 * Verify the format: the ASN.1 functions we use below allow a more
1824 * flexible format than what's mandated by RFC 5280.
1825 * Digit and date ranges will be verified in the conversion methods.
1827 for (i = 0; i < ctm->length - 1; i++) {
1828 if (!ascii_isdigit(ctm->data[i]))
1831 if (ctm->data[ctm->length - 1] != upper_z)
1835 * There is ASN1_UTCTIME_cmp_time_t but no
1836 * ASN1_GENERALIZEDTIME_cmp_time_t or ASN1_TIME_cmp_time_t,
1837 * so we go through ASN.1
1839 asn1_cmp_time = X509_time_adj(NULL, 0, cmp_time);
1840 if (asn1_cmp_time == NULL)
1842 if (!ASN1_TIME_diff(&day, &sec, ctm, asn1_cmp_time))
1846 * X509_cmp_time comparison is <=.
1847 * The return value 0 is reserved for errors.
1849 ret = (day >= 0 && sec >= 0) ? -1 : 1;
1852 ASN1_TIME_free(asn1_cmp_time);
1856 ASN1_TIME *X509_gmtime_adj(ASN1_TIME *s, long adj)
1858 return X509_time_adj(s, adj, NULL);
1861 ASN1_TIME *X509_time_adj(ASN1_TIME *s, long offset_sec, time_t *in_tm)
1863 return X509_time_adj_ex(s, 0, offset_sec, in_tm);
1866 ASN1_TIME *X509_time_adj_ex(ASN1_TIME *s,
1867 int offset_day, long offset_sec, time_t *in_tm)
1876 if (s && !(s->flags & ASN1_STRING_FLAG_MSTRING)) {
1877 if (s->type == V_ASN1_UTCTIME)
1878 return ASN1_UTCTIME_adj(s, t, offset_day, offset_sec);
1879 if (s->type == V_ASN1_GENERALIZEDTIME)
1880 return ASN1_GENERALIZEDTIME_adj(s, t, offset_day, offset_sec);
1882 return ASN1_TIME_adj(s, t, offset_day, offset_sec);
1885 int X509_get_pubkey_parameters(EVP_PKEY *pkey, STACK_OF(X509) *chain)
1887 EVP_PKEY *ktmp = NULL, *ktmp2;
1890 if ((pkey != NULL) && !EVP_PKEY_missing_parameters(pkey))
1893 for (i = 0; i < sk_X509_num(chain); i++) {
1894 ktmp = X509_get0_pubkey(sk_X509_value(chain, i));
1896 X509err(X509_F_X509_GET_PUBKEY_PARAMETERS,
1897 X509_R_UNABLE_TO_GET_CERTS_PUBLIC_KEY);
1900 if (!EVP_PKEY_missing_parameters(ktmp))
1904 X509err(X509_F_X509_GET_PUBKEY_PARAMETERS,
1905 X509_R_UNABLE_TO_FIND_PARAMETERS_IN_CHAIN);
1909 /* first, populate the other certs */
1910 for (j = i - 1; j >= 0; j--) {
1911 ktmp2 = X509_get0_pubkey(sk_X509_value(chain, j));
1912 EVP_PKEY_copy_parameters(ktmp2, ktmp);
1916 EVP_PKEY_copy_parameters(pkey, ktmp);
1920 /* Make a delta CRL as the diff between two full CRLs */
1922 X509_CRL *X509_CRL_diff(X509_CRL *base, X509_CRL *newer,
1923 EVP_PKEY *skey, const EVP_MD *md, unsigned int flags)
1925 X509_CRL *crl = NULL;
1927 STACK_OF(X509_REVOKED) *revs = NULL;
1928 /* CRLs can't be delta already */
1929 if (base->base_crl_number || newer->base_crl_number) {
1930 X509err(X509_F_X509_CRL_DIFF, X509_R_CRL_ALREADY_DELTA);
1933 /* Base and new CRL must have a CRL number */
1934 if (!base->crl_number || !newer->crl_number) {
1935 X509err(X509_F_X509_CRL_DIFF, X509_R_NO_CRL_NUMBER);
1938 /* Issuer names must match */
1939 if (X509_NAME_cmp(X509_CRL_get_issuer(base), X509_CRL_get_issuer(newer))) {
1940 X509err(X509_F_X509_CRL_DIFF, X509_R_ISSUER_MISMATCH);
1943 /* AKID and IDP must match */
1944 if (!crl_extension_match(base, newer, NID_authority_key_identifier)) {
1945 X509err(X509_F_X509_CRL_DIFF, X509_R_AKID_MISMATCH);
1948 if (!crl_extension_match(base, newer, NID_issuing_distribution_point)) {
1949 X509err(X509_F_X509_CRL_DIFF, X509_R_IDP_MISMATCH);
1952 /* Newer CRL number must exceed full CRL number */
1953 if (ASN1_INTEGER_cmp(newer->crl_number, base->crl_number) <= 0) {
1954 X509err(X509_F_X509_CRL_DIFF, X509_R_NEWER_CRL_NOT_NEWER);
1957 /* CRLs must verify */
1958 if (skey && (X509_CRL_verify(base, skey) <= 0 ||
1959 X509_CRL_verify(newer, skey) <= 0)) {
1960 X509err(X509_F_X509_CRL_DIFF, X509_R_CRL_VERIFY_FAILURE);
1963 /* Create new CRL */
1964 crl = X509_CRL_new();
1965 if (crl == NULL || !X509_CRL_set_version(crl, 1))
1967 /* Set issuer name */
1968 if (!X509_CRL_set_issuer_name(crl, X509_CRL_get_issuer(newer)))
1971 if (!X509_CRL_set1_lastUpdate(crl, X509_CRL_get0_lastUpdate(newer)))
1973 if (!X509_CRL_set1_nextUpdate(crl, X509_CRL_get0_nextUpdate(newer)))
1976 /* Set base CRL number: must be critical */
1978 if (!X509_CRL_add1_ext_i2d(crl, NID_delta_crl, base->crl_number, 1, 0))
1982 * Copy extensions across from newest CRL to delta: this will set CRL
1983 * number to correct value too.
1986 for (i = 0; i < X509_CRL_get_ext_count(newer); i++) {
1987 X509_EXTENSION *ext;
1988 ext = X509_CRL_get_ext(newer, i);
1989 if (!X509_CRL_add_ext(crl, ext, -1))
1993 /* Go through revoked entries, copying as needed */
1995 revs = X509_CRL_get_REVOKED(newer);
1997 for (i = 0; i < sk_X509_REVOKED_num(revs); i++) {
1998 X509_REVOKED *rvn, *rvtmp;
1999 rvn = sk_X509_REVOKED_value(revs, i);
2001 * Add only if not also in base. TODO: need something cleverer here
2002 * for some more complex CRLs covering multiple CAs.
2004 if (!X509_CRL_get0_by_serial(base, &rvtmp, &rvn->serialNumber)) {
2005 rvtmp = X509_REVOKED_dup(rvn);
2008 if (!X509_CRL_add0_revoked(crl, rvtmp)) {
2009 X509_REVOKED_free(rvtmp);
2014 /* TODO: optionally prune deleted entries */
2016 if (skey && md && !X509_CRL_sign(crl, skey, md))
2022 X509err(X509_F_X509_CRL_DIFF, ERR_R_MALLOC_FAILURE);
2027 int X509_STORE_CTX_set_ex_data(X509_STORE_CTX *ctx, int idx, void *data)
2029 return CRYPTO_set_ex_data(&ctx->ex_data, idx, data);
2032 void *X509_STORE_CTX_get_ex_data(X509_STORE_CTX *ctx, int idx)
2034 return CRYPTO_get_ex_data(&ctx->ex_data, idx);
2037 int X509_STORE_CTX_get_error(X509_STORE_CTX *ctx)
2042 void X509_STORE_CTX_set_error(X509_STORE_CTX *ctx, int err)
2047 int X509_STORE_CTX_get_error_depth(X509_STORE_CTX *ctx)
2049 return ctx->error_depth;
2052 void X509_STORE_CTX_set_error_depth(X509_STORE_CTX *ctx, int depth)
2054 ctx->error_depth = depth;
2057 X509 *X509_STORE_CTX_get_current_cert(X509_STORE_CTX *ctx)
2059 return ctx->current_cert;
2062 void X509_STORE_CTX_set_current_cert(X509_STORE_CTX *ctx, X509 *x)
2064 ctx->current_cert = x;
2067 STACK_OF(X509) *X509_STORE_CTX_get0_chain(X509_STORE_CTX *ctx)
2072 STACK_OF(X509) *X509_STORE_CTX_get1_chain(X509_STORE_CTX *ctx)
2076 return X509_chain_up_ref(ctx->chain);
2079 X509 *X509_STORE_CTX_get0_current_issuer(X509_STORE_CTX *ctx)
2081 return ctx->current_issuer;
2084 X509_CRL *X509_STORE_CTX_get0_current_crl(X509_STORE_CTX *ctx)
2086 return ctx->current_crl;
2089 X509_STORE_CTX *X509_STORE_CTX_get0_parent_ctx(X509_STORE_CTX *ctx)
2094 void X509_STORE_CTX_set_cert(X509_STORE_CTX *ctx, X509 *x)
2099 void X509_STORE_CTX_set0_crls(X509_STORE_CTX *ctx, STACK_OF(X509_CRL) *sk)
2104 int X509_STORE_CTX_set_purpose(X509_STORE_CTX *ctx, int purpose)
2107 * XXX: Why isn't this function always used to set the associated trust?
2108 * Should there even be a VPM->trust field at all? Or should the trust
2109 * always be inferred from the purpose by X509_STORE_CTX_init().
2111 return X509_STORE_CTX_purpose_inherit(ctx, 0, purpose, 0);
2114 int X509_STORE_CTX_set_trust(X509_STORE_CTX *ctx, int trust)
2117 * XXX: See above, this function would only be needed when the default
2118 * trust for the purpose needs an override in a corner case.
2120 return X509_STORE_CTX_purpose_inherit(ctx, 0, 0, trust);
2124 * This function is used to set the X509_STORE_CTX purpose and trust values.
2125 * This is intended to be used when another structure has its own trust and
2126 * purpose values which (if set) will be inherited by the ctx. If they aren't
2127 * set then we will usually have a default purpose in mind which should then
2128 * be used to set the trust value. An example of this is SSL use: an SSL
2129 * structure will have its own purpose and trust settings which the
2130 * application can set: if they aren't set then we use the default of SSL
2134 int X509_STORE_CTX_purpose_inherit(X509_STORE_CTX *ctx, int def_purpose,
2135 int purpose, int trust)
2138 /* If purpose not set use default */
2140 purpose = def_purpose;
2141 /* If we have a purpose then check it is valid */
2144 idx = X509_PURPOSE_get_by_id(purpose);
2146 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2147 X509_R_UNKNOWN_PURPOSE_ID);
2150 ptmp = X509_PURPOSE_get0(idx);
2151 if (ptmp->trust == X509_TRUST_DEFAULT) {
2152 idx = X509_PURPOSE_get_by_id(def_purpose);
2154 * XXX: In the two callers above def_purpose is always 0, which is
2155 * not a known value, so idx will always be -1. How is the
2156 * X509_TRUST_DEFAULT case actually supposed to be handled?
2159 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2160 X509_R_UNKNOWN_PURPOSE_ID);
2163 ptmp = X509_PURPOSE_get0(idx);
2165 /* If trust not set then get from purpose default */
2167 trust = ptmp->trust;
2170 idx = X509_TRUST_get_by_id(trust);
2172 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2173 X509_R_UNKNOWN_TRUST_ID);
2178 if (purpose && !ctx->param->purpose)
2179 ctx->param->purpose = purpose;
2180 if (trust && !ctx->param->trust)
2181 ctx->param->trust = trust;
2185 X509_STORE_CTX *X509_STORE_CTX_new(void)
2187 X509_STORE_CTX *ctx = OPENSSL_zalloc(sizeof(*ctx));
2190 X509err(X509_F_X509_STORE_CTX_NEW, ERR_R_MALLOC_FAILURE);
2196 void X509_STORE_CTX_free(X509_STORE_CTX *ctx)
2201 X509_STORE_CTX_cleanup(ctx);
2205 int X509_STORE_CTX_init(X509_STORE_CTX *ctx, X509_STORE *store, X509 *x509,
2206 STACK_OF(X509) *chain)
2212 ctx->untrusted = chain;
2214 ctx->num_untrusted = 0;
2215 ctx->other_ctx = NULL;
2219 ctx->explicit_policy = 0;
2220 ctx->error_depth = 0;
2221 ctx->current_cert = NULL;
2222 ctx->current_issuer = NULL;
2223 ctx->current_crl = NULL;
2224 ctx->current_crl_score = 0;
2225 ctx->current_reasons = 0;
2229 ctx->bare_ta_signed = 0;
2230 /* Zero ex_data to make sure we're cleanup-safe */
2231 memset(&ctx->ex_data, 0, sizeof(ctx->ex_data));
2233 /* store->cleanup is always 0 in OpenSSL, if set must be idempotent */
2235 ctx->cleanup = store->cleanup;
2239 if (store && store->check_issued)
2240 ctx->check_issued = store->check_issued;
2242 ctx->check_issued = check_issued;
2244 if (store && store->get_issuer)
2245 ctx->get_issuer = store->get_issuer;
2247 ctx->get_issuer = X509_STORE_CTX_get1_issuer;
2249 if (store && store->verify_cb)
2250 ctx->verify_cb = store->verify_cb;
2252 ctx->verify_cb = null_callback;
2254 if (store && store->verify)
2255 ctx->verify = store->verify;
2257 ctx->verify = internal_verify;
2259 if (store && store->check_revocation)
2260 ctx->check_revocation = store->check_revocation;
2262 ctx->check_revocation = check_revocation;
2264 if (store && store->get_crl)
2265 ctx->get_crl = store->get_crl;
2267 ctx->get_crl = NULL;
2269 if (store && store->check_crl)
2270 ctx->check_crl = store->check_crl;
2272 ctx->check_crl = check_crl;
2274 if (store && store->cert_crl)
2275 ctx->cert_crl = store->cert_crl;
2277 ctx->cert_crl = cert_crl;
2279 if (store && store->check_policy)
2280 ctx->check_policy = store->check_policy;
2282 ctx->check_policy = check_policy;
2284 if (store && store->lookup_certs)
2285 ctx->lookup_certs = store->lookup_certs;
2287 ctx->lookup_certs = X509_STORE_CTX_get1_certs;
2289 if (store && store->lookup_crls)
2290 ctx->lookup_crls = store->lookup_crls;
2292 ctx->lookup_crls = X509_STORE_CTX_get1_crls;
2294 ctx->param = X509_VERIFY_PARAM_new();
2295 if (ctx->param == NULL) {
2296 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2301 * Inherit callbacks and flags from X509_STORE if not set use defaults.
2304 ret = X509_VERIFY_PARAM_inherit(ctx->param, store->param);
2306 ctx->param->inh_flags |= X509_VP_FLAG_DEFAULT | X509_VP_FLAG_ONCE;
2309 ret = X509_VERIFY_PARAM_inherit(ctx->param,
2310 X509_VERIFY_PARAM_lookup("default"));
2313 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2318 * XXX: For now, continue to inherit trust from VPM, but infer from the
2319 * purpose if this still yields the default value.
2321 if (ctx->param->trust == X509_TRUST_DEFAULT) {
2322 int idx = X509_PURPOSE_get_by_id(ctx->param->purpose);
2323 X509_PURPOSE *xp = X509_PURPOSE_get0(idx);
2326 ctx->param->trust = X509_PURPOSE_get_trust(xp);
2329 if (CRYPTO_new_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx,
2332 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2336 * On error clean up allocated storage, if the store context was not
2337 * allocated with X509_STORE_CTX_new() this is our last chance to do so.
2339 X509_STORE_CTX_cleanup(ctx);
2344 * Set alternative lookup method: just a STACK of trusted certificates. This
2345 * avoids X509_STORE nastiness where it isn't needed.
2347 void X509_STORE_CTX_set0_trusted_stack(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2349 ctx->other_ctx = sk;
2350 ctx->get_issuer = get_issuer_sk;
2351 ctx->lookup_certs = lookup_certs_sk;
2354 void X509_STORE_CTX_cleanup(X509_STORE_CTX *ctx)
2357 * We need to be idempotent because, unfortunately, free() also calls
2358 * cleanup(), so the natural call sequence new(), init(), cleanup(), free()
2359 * calls cleanup() for the same object twice! Thus we must zero the
2360 * pointers below after they're freed!
2362 /* Seems to always be 0 in OpenSSL, do this at most once. */
2363 if (ctx->cleanup != NULL) {
2365 ctx->cleanup = NULL;
2367 if (ctx->param != NULL) {
2368 if (ctx->parent == NULL)
2369 X509_VERIFY_PARAM_free(ctx->param);
2372 X509_policy_tree_free(ctx->tree);
2374 sk_X509_pop_free(ctx->chain, X509_free);
2376 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx, &(ctx->ex_data));
2377 memset(&ctx->ex_data, 0, sizeof(ctx->ex_data));
2380 void X509_STORE_CTX_set_depth(X509_STORE_CTX *ctx, int depth)
2382 X509_VERIFY_PARAM_set_depth(ctx->param, depth);
2385 void X509_STORE_CTX_set_flags(X509_STORE_CTX *ctx, unsigned long flags)
2387 X509_VERIFY_PARAM_set_flags(ctx->param, flags);
2390 void X509_STORE_CTX_set_time(X509_STORE_CTX *ctx, unsigned long flags,
2393 X509_VERIFY_PARAM_set_time(ctx->param, t);
2396 X509 *X509_STORE_CTX_get0_cert(X509_STORE_CTX *ctx)
2401 STACK_OF(X509) *X509_STORE_CTX_get0_untrusted(X509_STORE_CTX *ctx)
2403 return ctx->untrusted;
2406 void X509_STORE_CTX_set0_untrusted(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2408 ctx->untrusted = sk;
2411 void X509_STORE_CTX_set0_verified_chain(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2413 sk_X509_pop_free(ctx->chain, X509_free);
2417 void X509_STORE_CTX_set_verify_cb(X509_STORE_CTX *ctx,
2418 X509_STORE_CTX_verify_cb verify_cb)
2420 ctx->verify_cb = verify_cb;
2423 X509_STORE_CTX_verify_cb X509_STORE_CTX_get_verify_cb(X509_STORE_CTX *ctx)
2425 return ctx->verify_cb;
2428 void X509_STORE_CTX_set_verify(X509_STORE_CTX *ctx,
2429 X509_STORE_CTX_verify_fn verify)
2431 ctx->verify = verify;
2434 X509_STORE_CTX_verify_fn X509_STORE_CTX_get_verify(X509_STORE_CTX *ctx)
2439 X509_STORE_CTX_get_issuer_fn X509_STORE_CTX_get_get_issuer(X509_STORE_CTX *ctx)
2441 return ctx->get_issuer;
2444 X509_STORE_CTX_check_issued_fn X509_STORE_CTX_get_check_issued(X509_STORE_CTX *ctx)
2446 return ctx->check_issued;
2449 X509_STORE_CTX_check_revocation_fn X509_STORE_CTX_get_check_revocation(X509_STORE_CTX *ctx)
2451 return ctx->check_revocation;
2454 X509_STORE_CTX_get_crl_fn X509_STORE_CTX_get_get_crl(X509_STORE_CTX *ctx)
2456 return ctx->get_crl;
2459 X509_STORE_CTX_check_crl_fn X509_STORE_CTX_get_check_crl(X509_STORE_CTX *ctx)
2461 return ctx->check_crl;
2464 X509_STORE_CTX_cert_crl_fn X509_STORE_CTX_get_cert_crl(X509_STORE_CTX *ctx)
2466 return ctx->cert_crl;
2469 X509_STORE_CTX_check_policy_fn X509_STORE_CTX_get_check_policy(X509_STORE_CTX *ctx)
2471 return ctx->check_policy;
2474 X509_STORE_CTX_lookup_certs_fn X509_STORE_CTX_get_lookup_certs(X509_STORE_CTX *ctx)
2476 return ctx->lookup_certs;
2479 X509_STORE_CTX_lookup_crls_fn X509_STORE_CTX_get_lookup_crls(X509_STORE_CTX *ctx)
2481 return ctx->lookup_crls;
2484 X509_STORE_CTX_cleanup_fn X509_STORE_CTX_get_cleanup(X509_STORE_CTX *ctx)
2486 return ctx->cleanup;
2489 X509_POLICY_TREE *X509_STORE_CTX_get0_policy_tree(X509_STORE_CTX *ctx)
2494 int X509_STORE_CTX_get_explicit_policy(X509_STORE_CTX *ctx)
2496 return ctx->explicit_policy;
2499 int X509_STORE_CTX_get_num_untrusted(X509_STORE_CTX *ctx)
2501 return ctx->num_untrusted;
2504 int X509_STORE_CTX_set_default(X509_STORE_CTX *ctx, const char *name)
2506 const X509_VERIFY_PARAM *param;
2507 param = X509_VERIFY_PARAM_lookup(name);
2510 return X509_VERIFY_PARAM_inherit(ctx->param, param);
2513 X509_VERIFY_PARAM *X509_STORE_CTX_get0_param(X509_STORE_CTX *ctx)
2518 void X509_STORE_CTX_set0_param(X509_STORE_CTX *ctx, X509_VERIFY_PARAM *param)
2520 X509_VERIFY_PARAM_free(ctx->param);
2524 void X509_STORE_CTX_set0_dane(X509_STORE_CTX *ctx, SSL_DANE *dane)
2529 static unsigned char *dane_i2d(
2532 unsigned int *i2dlen)
2534 unsigned char *buf = NULL;
2538 * Extract ASN.1 DER form of certificate or public key.
2541 case DANETLS_SELECTOR_CERT:
2542 len = i2d_X509(cert, &buf);
2544 case DANETLS_SELECTOR_SPKI:
2545 len = i2d_X509_PUBKEY(X509_get_X509_PUBKEY(cert), &buf);
2548 X509err(X509_F_DANE_I2D, X509_R_BAD_SELECTOR);
2552 if (len < 0 || buf == NULL) {
2553 X509err(X509_F_DANE_I2D, ERR_R_MALLOC_FAILURE);
2557 *i2dlen = (unsigned int)len;
2561 #define DANETLS_NONE 256 /* impossible uint8_t */
2563 static int dane_match(X509_STORE_CTX *ctx, X509 *cert, int depth)
2565 SSL_DANE *dane = ctx->dane;
2566 unsigned usage = DANETLS_NONE;
2567 unsigned selector = DANETLS_NONE;
2568 unsigned ordinal = DANETLS_NONE;
2569 unsigned mtype = DANETLS_NONE;
2570 unsigned char *i2dbuf = NULL;
2571 unsigned int i2dlen = 0;
2572 unsigned char mdbuf[EVP_MAX_MD_SIZE];
2573 unsigned char *cmpbuf = NULL;
2574 unsigned int cmplen = 0;
2578 danetls_record *t = NULL;
2581 mask = (depth == 0) ? DANETLS_EE_MASK : DANETLS_TA_MASK;
2584 * The trust store is not applicable with DANE-TA(2)
2586 if (depth >= ctx->num_untrusted)
2587 mask &= DANETLS_PKIX_MASK;
2590 * If we've previously matched a PKIX-?? record, no need to test any
2591 * further PKIX-?? records, it remains to just build the PKIX chain.
2592 * Had the match been a DANE-?? record, we'd be done already.
2594 if (dane->mdpth >= 0)
2595 mask &= ~DANETLS_PKIX_MASK;
2598 * https://tools.ietf.org/html/rfc7671#section-5.1
2599 * https://tools.ietf.org/html/rfc7671#section-5.2
2600 * https://tools.ietf.org/html/rfc7671#section-5.3
2601 * https://tools.ietf.org/html/rfc7671#section-5.4
2603 * We handle DANE-EE(3) records first as they require no chain building
2604 * and no expiration or hostname checks. We also process digests with
2605 * higher ordinals first and ignore lower priorities except Full(0) which
2606 * is always processed (last). If none match, we then process PKIX-EE(1).
2608 * NOTE: This relies on DANE usages sorting before the corresponding PKIX
2609 * usages in SSL_dane_tlsa_add(), and also on descending sorting of digest
2610 * priorities. See twin comment in ssl/ssl_lib.c.
2612 * We expect that most TLSA RRsets will have just a single usage, so we
2613 * don't go out of our way to cache multiple selector-specific i2d buffers
2614 * across usages, but if the selector happens to remain the same as switch
2615 * usages, that's OK. Thus, a set of "3 1 1", "3 0 1", "1 1 1", "1 0 1",
2616 * records would result in us generating each of the certificate and public
2617 * key DER forms twice, but more typically we'd just see multiple "3 1 1"
2618 * or multiple "3 0 1" records.
2620 * As soon as we find a match at any given depth, we stop, because either
2621 * we've matched a DANE-?? record and the peer is authenticated, or, after
2622 * exhausting all DANE-?? records, we've matched a PKIX-?? record, which is
2623 * sufficient for DANE, and what remains to do is ordinary PKIX validation.
2625 recnum = (dane->umask & mask) ? sk_danetls_record_num(dane->trecs) : 0;
2626 for (i = 0; matched == 0 && i < recnum; ++i) {
2627 t = sk_danetls_record_value(dane->trecs, i);
2628 if ((DANETLS_USAGE_BIT(t->usage) & mask) == 0)
2630 if (t->usage != usage) {
2633 /* Reset digest agility for each usage/selector pair */
2634 mtype = DANETLS_NONE;
2635 ordinal = dane->dctx->mdord[t->mtype];
2637 if (t->selector != selector) {
2638 selector = t->selector;
2640 /* Update per-selector state */
2641 OPENSSL_free(i2dbuf);
2642 i2dbuf = dane_i2d(cert, selector, &i2dlen);
2646 /* Reset digest agility for each usage/selector pair */
2647 mtype = DANETLS_NONE;
2648 ordinal = dane->dctx->mdord[t->mtype];
2649 } else if (t->mtype != DANETLS_MATCHING_FULL) {
2653 * <https://tools.ietf.org/html/rfc7671#section-9>
2655 * For a fixed selector, after processing all records with the
2656 * highest mtype ordinal, ignore all mtypes with lower ordinals
2657 * other than "Full".
2659 if (dane->dctx->mdord[t->mtype] < ordinal)
2664 * Each time we hit a (new selector or) mtype, re-compute the relevant
2665 * digest, more complex caching is not worth the code space.
2667 if (t->mtype != mtype) {
2668 const EVP_MD *md = dane->dctx->mdevp[mtype = t->mtype];
2674 if (!EVP_Digest(i2dbuf, i2dlen, cmpbuf, &cmplen, md, 0)) {
2682 * Squirrel away the certificate and depth if we have a match. Any
2683 * DANE match is dispositive, but with PKIX we still need to build a
2686 if (cmplen == t->dlen &&
2687 memcmp(cmpbuf, t->data, cmplen) == 0) {
2688 if (DANETLS_USAGE_BIT(usage) & DANETLS_DANE_MASK)
2690 if (matched || dane->mdpth < 0) {
2691 dane->mdpth = depth;
2693 OPENSSL_free(dane->mcert);
2701 /* Clear the one-element DER cache */
2702 OPENSSL_free(i2dbuf);
2706 static int check_dane_issuer(X509_STORE_CTX *ctx, int depth)
2708 SSL_DANE *dane = ctx->dane;
2712 if (!DANETLS_HAS_TA(dane) || depth == 0)
2713 return X509_TRUST_UNTRUSTED;
2716 * Record any DANE trust-anchor matches, for the first depth to test, if
2717 * there's one at that depth. (This'll be false for length 1 chains looking
2718 * for an exact match for the leaf certificate).
2720 cert = sk_X509_value(ctx->chain, depth);
2721 if (cert != NULL && (matched = dane_match(ctx, cert, depth)) < 0)
2722 return X509_TRUST_REJECTED;
2724 ctx->num_untrusted = depth - 1;
2725 return X509_TRUST_TRUSTED;
2728 return X509_TRUST_UNTRUSTED;
2731 static int check_dane_pkeys(X509_STORE_CTX *ctx)
2733 SSL_DANE *dane = ctx->dane;
2735 int num = ctx->num_untrusted;
2736 X509 *cert = sk_X509_value(ctx->chain, num - 1);
2737 int recnum = sk_danetls_record_num(dane->trecs);
2740 for (i = 0; i < recnum; ++i) {
2741 t = sk_danetls_record_value(dane->trecs, i);
2742 if (t->usage != DANETLS_USAGE_DANE_TA ||
2743 t->selector != DANETLS_SELECTOR_SPKI ||
2744 t->mtype != DANETLS_MATCHING_FULL ||
2745 X509_verify(cert, t->spki) <= 0)
2748 /* Clear any PKIX-?? matches that failed to extend to a full chain */
2749 X509_free(dane->mcert);
2752 /* Record match via a bare TA public key */
2753 ctx->bare_ta_signed = 1;
2754 dane->mdpth = num - 1;
2757 /* Prune any excess chain certificates */
2758 num = sk_X509_num(ctx->chain);
2759 for (; num > ctx->num_untrusted; --num)
2760 X509_free(sk_X509_pop(ctx->chain));
2762 return X509_TRUST_TRUSTED;
2765 return X509_TRUST_UNTRUSTED;
2768 static void dane_reset(SSL_DANE *dane)
2771 * Reset state to verify another chain, or clear after failure.
2773 X509_free(dane->mcert);
2780 static int check_leaf_suiteb(X509_STORE_CTX *ctx, X509 *cert)
2782 int err = X509_chain_check_suiteb(NULL, cert, NULL, ctx->param->flags);
2784 if (err == X509_V_OK)
2786 return verify_cb_cert(ctx, cert, 0, err);
2789 static int dane_verify(X509_STORE_CTX *ctx)
2791 X509 *cert = ctx->cert;
2792 SSL_DANE *dane = ctx->dane;
2799 * When testing the leaf certificate, if we match a DANE-EE(3) record,
2800 * dane_match() returns 1 and we're done. If however we match a PKIX-EE(1)
2801 * record, the match depth and matching TLSA record are recorded, but the
2802 * return value is 0, because we still need to find a PKIX trust-anchor.
2803 * Therefore, when DANE authentication is enabled (required), we're done
2805 * + matched < 0, internal error.
2806 * + matched == 1, we matched a DANE-EE(3) record
2807 * + matched == 0, mdepth < 0 (no PKIX-EE match) and there are no
2808 * DANE-TA(2) or PKIX-TA(0) to test.
2810 matched = dane_match(ctx, ctx->cert, 0);
2811 done = matched != 0 || (!DANETLS_HAS_TA(dane) && dane->mdpth < 0);
2814 X509_get_pubkey_parameters(NULL, ctx->chain);
2817 /* Callback invoked as needed */
2818 if (!check_leaf_suiteb(ctx, cert))
2820 /* Callback invoked as needed */
2821 if ((dane->flags & DANE_FLAG_NO_DANE_EE_NAMECHECKS) == 0 &&
2824 /* Bypass internal_verify(), issue depth 0 success callback */
2825 ctx->error_depth = 0;
2826 ctx->current_cert = cert;
2827 return ctx->verify_cb(1, ctx);
2831 ctx->error_depth = 0;
2832 ctx->current_cert = cert;
2833 ctx->error = X509_V_ERR_OUT_OF_MEM;
2838 /* Fail early, TA-based success is not possible */
2839 if (!check_leaf_suiteb(ctx, cert))
2841 return verify_cb_cert(ctx, cert, 0, X509_V_ERR_DANE_NO_MATCH);
2845 * Chain verification for usages 0/1/2. TLSA record matching of depth > 0
2846 * certificates happens in-line with building the rest of the chain.
2848 return verify_chain(ctx);
2851 /* Get issuer, without duplicate suppression */
2852 static int get_issuer(X509 **issuer, X509_STORE_CTX *ctx, X509 *cert)
2854 STACK_OF(X509) *saved_chain = ctx->chain;
2858 ok = ctx->get_issuer(issuer, ctx, cert);
2859 ctx->chain = saved_chain;
2864 static int build_chain(X509_STORE_CTX *ctx)
2866 SSL_DANE *dane = ctx->dane;
2867 int num = sk_X509_num(ctx->chain);
2868 X509 *cert = sk_X509_value(ctx->chain, num - 1);
2869 int ss = cert_self_signed(cert);
2870 STACK_OF(X509) *sktmp = NULL;
2871 unsigned int search;
2872 int may_trusted = 0;
2873 int may_alternate = 0;
2874 int trust = X509_TRUST_UNTRUSTED;
2875 int alt_untrusted = 0;
2880 /* Our chain starts with a single untrusted element. */
2881 if (!ossl_assert(num == 1 && ctx->num_untrusted == num)) {
2882 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
2883 ctx->error = X509_V_ERR_UNSPECIFIED;
2887 #define S_DOUNTRUSTED (1 << 0) /* Search untrusted chain */
2888 #define S_DOTRUSTED (1 << 1) /* Search trusted store */
2889 #define S_DOALTERNATE (1 << 2) /* Retry with pruned alternate chain */
2891 * Set up search policy, untrusted if possible, trusted-first if enabled.
2892 * If we're doing DANE and not doing PKIX-TA/PKIX-EE, we never look in the
2893 * trust_store, otherwise we might look there first. If not trusted-first,
2894 * and alternate chains are not disabled, try building an alternate chain
2895 * if no luck with untrusted first.
2897 search = (ctx->untrusted != NULL) ? S_DOUNTRUSTED : 0;
2898 if (DANETLS_HAS_PKIX(dane) || !DANETLS_HAS_DANE(dane)) {
2899 if (search == 0 || ctx->param->flags & X509_V_FLAG_TRUSTED_FIRST)
2900 search |= S_DOTRUSTED;
2901 else if (!(ctx->param->flags & X509_V_FLAG_NO_ALT_CHAINS))
2907 * Shallow-copy the stack of untrusted certificates (with TLS, this is
2908 * typically the content of the peer's certificate message) so can make
2909 * multiple passes over it, while free to remove elements as we go.
2911 if (ctx->untrusted && (sktmp = sk_X509_dup(ctx->untrusted)) == NULL) {
2912 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2913 ctx->error = X509_V_ERR_OUT_OF_MEM;
2918 * If we got any "DANE-TA(2) Cert(0) Full(0)" trust-anchors from DNS, add
2919 * them to our working copy of the untrusted certificate stack. Since the
2920 * caller of X509_STORE_CTX_init() may have provided only a leaf cert with
2921 * no corresponding stack of untrusted certificates, we may need to create
2922 * an empty stack first. [ At present only the ssl library provides DANE
2923 * support, and ssl_verify_cert_chain() always provides a non-null stack
2924 * containing at least the leaf certificate, but we must be prepared for
2927 if (DANETLS_ENABLED(dane) && dane->certs != NULL) {
2928 if (sktmp == NULL && (sktmp = sk_X509_new_null()) == NULL) {
2929 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2930 ctx->error = X509_V_ERR_OUT_OF_MEM;
2933 for (i = 0; i < sk_X509_num(dane->certs); ++i) {
2934 if (!sk_X509_push(sktmp, sk_X509_value(dane->certs, i))) {
2935 sk_X509_free(sktmp);
2936 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2937 ctx->error = X509_V_ERR_OUT_OF_MEM;
2944 * Still absurdly large, but arithmetically safe, a lower hard upper bound
2945 * might be reasonable.
2947 if (ctx->param->depth > INT_MAX/2)
2948 ctx->param->depth = INT_MAX/2;
2951 * Try to Extend the chain until we reach an ultimately trusted issuer.
2952 * Build chains up to one longer the limit, later fail if we hit the limit,
2953 * with an X509_V_ERR_CERT_CHAIN_TOO_LONG error code.
2955 depth = ctx->param->depth + 1;
2957 while (search != 0) {
2962 * Look in the trust store if enabled for first lookup, or we've run
2963 * out of untrusted issuers and search here is not disabled. When we
2964 * reach the depth limit, we stop extending the chain, if by that point
2965 * we've not found a trust-anchor, any trusted chain would be too long.
2967 * The error reported to the application verify callback is at the
2968 * maximal valid depth with the current certificate equal to the last
2969 * not ultimately-trusted issuer. For example, with verify_depth = 0,
2970 * the callback will report errors at depth=1 when the immediate issuer
2971 * of the leaf certificate is not a trust anchor. No attempt will be
2972 * made to locate an issuer for that certificate, since such a chain
2973 * would be a-priori too long.
2975 if ((search & S_DOTRUSTED) != 0) {
2976 i = num = sk_X509_num(ctx->chain);
2977 if ((search & S_DOALTERNATE) != 0) {
2979 * As high up the chain as we can, look for an alternative
2980 * trusted issuer of an untrusted certificate that currently
2981 * has an untrusted issuer. We use the alt_untrusted variable
2982 * to track how far up the chain we find the first match. It
2983 * is only if and when we find a match, that we prune the chain
2984 * and reset ctx->num_untrusted to the reduced count of
2985 * untrusted certificates. While we're searching for such a
2986 * match (which may never be found), it is neither safe nor
2987 * wise to preemptively modify either the chain or
2988 * ctx->num_untrusted.
2990 * Note, like ctx->num_untrusted, alt_untrusted is a count of
2991 * untrusted certificates, not a "depth".
2995 x = sk_X509_value(ctx->chain, i-1);
2997 ok = (depth < num) ? 0 : get_issuer(&xtmp, ctx, x);
3000 trust = X509_TRUST_REJECTED;
3001 ctx->error = X509_V_ERR_STORE_LOOKUP;
3008 * Alternative trusted issuer for a mid-chain untrusted cert?
3009 * Pop the untrusted cert's successors and retry. We might now
3010 * be able to complete a valid chain via the trust store. Note
3011 * that despite the current trust-store match we might still
3012 * fail complete the chain to a suitable trust-anchor, in which
3013 * case we may prune some more untrusted certificates and try
3014 * again. Thus the S_DOALTERNATE bit may yet be turned on
3015 * again with an even shorter untrusted chain!
3017 * If in the process we threw away our matching PKIX-TA trust
3018 * anchor, reset DANE trust. We might find a suitable trusted
3019 * certificate among the ones from the trust store.
3021 if ((search & S_DOALTERNATE) != 0) {
3022 if (!ossl_assert(num > i && i > 0 && ss == 0)) {
3023 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
3025 trust = X509_TRUST_REJECTED;
3026 ctx->error = X509_V_ERR_UNSPECIFIED;
3030 search &= ~S_DOALTERNATE;
3031 for (; num > i; --num)
3032 X509_free(sk_X509_pop(ctx->chain));
3033 ctx->num_untrusted = num;
3035 if (DANETLS_ENABLED(dane) &&
3036 dane->mdpth >= ctx->num_untrusted) {
3038 X509_free(dane->mcert);
3041 if (DANETLS_ENABLED(dane) &&
3042 dane->pdpth >= ctx->num_untrusted)
3047 * Self-signed untrusted certificates get replaced by their
3048 * trusted matching issuer. Otherwise, grow the chain.
3051 if (!sk_X509_push(ctx->chain, x = xtmp)) {
3053 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
3054 trust = X509_TRUST_REJECTED;
3055 ctx->error = X509_V_ERR_OUT_OF_MEM;
3059 ss = cert_self_signed(x);
3060 } else if (num == ctx->num_untrusted) {
3062 * We have a self-signed certificate that has the same
3063 * subject name (and perhaps keyid and/or serial number) as
3064 * a trust-anchor. We must have an exact match to avoid
3065 * possible impersonation via key substitution etc.
3067 if (X509_cmp(x, xtmp) != 0) {
3068 /* Self-signed untrusted mimic. */
3073 ctx->num_untrusted = --num;
3074 (void) sk_X509_set(ctx->chain, num, x = xtmp);
3079 * We've added a new trusted certificate to the chain, recheck
3080 * trust. If not done, and not self-signed look deeper.
3081 * Whether or not we're doing "trusted first", we no longer
3082 * look for untrusted certificates from the peer's chain.
3084 * At this point ctx->num_trusted and num must reflect the
3085 * correct number of untrusted certificates, since the DANE
3086 * logic in check_trust() depends on distinguishing CAs from
3087 * "the wire" from CAs from the trust store. In particular, the
3088 * certificate at depth "num" should be the new trusted
3089 * certificate with ctx->num_untrusted <= num.
3092 if (!ossl_assert(ctx->num_untrusted <= num)) {
3093 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
3094 trust = X509_TRUST_REJECTED;
3095 ctx->error = X509_V_ERR_UNSPECIFIED;
3099 search &= ~S_DOUNTRUSTED;
3100 switch (trust = check_trust(ctx, num)) {
3101 case X509_TRUST_TRUSTED:
3102 case X509_TRUST_REJECTED:
3112 * No dispositive decision, and either self-signed or no match, if
3113 * we were doing untrusted-first, and alt-chains are not disabled,
3114 * do that, by repeatedly losing one untrusted element at a time,
3115 * and trying to extend the shorted chain.
3117 if ((search & S_DOUNTRUSTED) == 0) {
3118 /* Continue search for a trusted issuer of a shorter chain? */
3119 if ((search & S_DOALTERNATE) != 0 && --alt_untrusted > 0)
3121 /* Still no luck and no fallbacks left? */
3122 if (!may_alternate || (search & S_DOALTERNATE) != 0 ||
3123 ctx->num_untrusted < 2)
3125 /* Search for a trusted issuer of a shorter chain */
3126 search |= S_DOALTERNATE;
3127 alt_untrusted = ctx->num_untrusted - 1;
3133 * Extend chain with peer-provided certificates
3135 if ((search & S_DOUNTRUSTED) != 0) {
3136 num = sk_X509_num(ctx->chain);
3137 if (!ossl_assert(num == ctx->num_untrusted)) {
3138 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
3139 trust = X509_TRUST_REJECTED;
3140 ctx->error = X509_V_ERR_UNSPECIFIED;
3144 x = sk_X509_value(ctx->chain, num-1);
3147 * Once we run out of untrusted issuers, we stop looking for more
3148 * and start looking only in the trust store if enabled.
3150 xtmp = (ss || depth < num) ? NULL : find_issuer(ctx, sktmp, x);
3152 search &= ~S_DOUNTRUSTED;
3154 search |= S_DOTRUSTED;
3158 /* Drop this issuer from future consideration */
3159 (void) sk_X509_delete_ptr(sktmp, xtmp);
3161 if (!sk_X509_push(ctx->chain, xtmp)) {
3162 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
3163 trust = X509_TRUST_REJECTED;
3164 ctx->error = X509_V_ERR_OUT_OF_MEM;
3169 X509_up_ref(x = xtmp);
3170 ++ctx->num_untrusted;
3171 ss = cert_self_signed(xtmp);
3174 * Check for DANE-TA trust of the topmost untrusted certificate.
3176 switch (trust = check_dane_issuer(ctx, ctx->num_untrusted - 1)) {
3177 case X509_TRUST_TRUSTED:
3178 case X509_TRUST_REJECTED:
3184 sk_X509_free(sktmp);
3187 * Last chance to make a trusted chain, either bare DANE-TA public-key
3188 * signers, or else direct leaf PKIX trust.
3190 num = sk_X509_num(ctx->chain);
3192 if (trust == X509_TRUST_UNTRUSTED && DANETLS_HAS_DANE_TA(dane))
3193 trust = check_dane_pkeys(ctx);
3194 if (trust == X509_TRUST_UNTRUSTED && num == ctx->num_untrusted)
3195 trust = check_trust(ctx, num);
3199 case X509_TRUST_TRUSTED:
3201 case X509_TRUST_REJECTED:
3202 /* Callback already issued */
3204 case X509_TRUST_UNTRUSTED:
3206 num = sk_X509_num(ctx->chain);
3208 return verify_cb_cert(ctx, NULL, num-1,
3209 X509_V_ERR_CERT_CHAIN_TOO_LONG);
3210 if (DANETLS_ENABLED(dane) &&
3211 (!DANETLS_HAS_PKIX(dane) || dane->pdpth >= 0))
3212 return verify_cb_cert(ctx, NULL, num-1, X509_V_ERR_DANE_NO_MATCH);
3213 if (ss && sk_X509_num(ctx->chain) == 1)
3214 return verify_cb_cert(ctx, NULL, num-1,
3215 X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT);
3217 return verify_cb_cert(ctx, NULL, num-1,
3218 X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN);
3219 if (ctx->num_untrusted < num)
3220 return verify_cb_cert(ctx, NULL, num-1,
3221 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT);
3222 return verify_cb_cert(ctx, NULL, num-1,
3223 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY);
3227 static const int minbits_table[] = { 80, 112, 128, 192, 256 };
3228 static const int NUM_AUTH_LEVELS = OSSL_NELEM(minbits_table);
3231 * Check whether the public key of ``cert`` meets the security level of
3234 * Returns 1 on success, 0 otherwise.
3236 static int check_key_level(X509_STORE_CTX *ctx, X509 *cert)
3238 EVP_PKEY *pkey = X509_get0_pubkey(cert);
3239 int level = ctx->param->auth_level;
3242 * At security level zero, return without checking for a supported public
3243 * key type. Some engines support key types not understood outside the
3244 * engine, and we only need to understand the key when enforcing a security
3250 /* Unsupported or malformed keys are not secure */
3254 if (level > NUM_AUTH_LEVELS)
3255 level = NUM_AUTH_LEVELS;
3257 return EVP_PKEY_security_bits(pkey) >= minbits_table[level - 1];
3261 * Check whether the signature digest algorithm of ``cert`` meets the security
3262 * level of ``ctx``. Should not be checked for trust anchors (whether
3263 * self-signed or otherwise).
3265 * Returns 1 on success, 0 otherwise.
3267 static int check_sig_level(X509_STORE_CTX *ctx, X509 *cert)
3270 int level = ctx->param->auth_level;
3274 if (level > NUM_AUTH_LEVELS)
3275 level = NUM_AUTH_LEVELS;
3277 if (!X509_get_signature_info(cert, NULL, NULL, &secbits, NULL))
3280 return secbits >= minbits_table[level - 1];