2 * Copyright 1995-2020 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the Apache License 2.0 (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
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"
29 DEFINE_STACK_OF(X509_REVOKED)
30 DEFINE_STACK_OF(GENERAL_NAME)
31 DEFINE_STACK_OF(X509_CRL)
32 DEFINE_STACK_OF(DIST_POINT)
33 DEFINE_STACK_OF_STRING()
35 /* CRL score values */
37 /* No unhandled critical extensions */
39 #define CRL_SCORE_NOCRITICAL 0x100
41 /* certificate is within CRL scope */
43 #define CRL_SCORE_SCOPE 0x080
47 #define CRL_SCORE_TIME 0x040
49 /* Issuer name matches certificate */
51 #define CRL_SCORE_ISSUER_NAME 0x020
53 /* If this score or above CRL is probably valid */
55 #define CRL_SCORE_VALID (CRL_SCORE_NOCRITICAL|CRL_SCORE_TIME|CRL_SCORE_SCOPE)
57 /* CRL issuer is certificate issuer */
59 #define CRL_SCORE_ISSUER_CERT 0x018
61 /* CRL issuer is on certificate path */
63 #define CRL_SCORE_SAME_PATH 0x008
65 /* CRL issuer matches CRL AKID */
67 #define CRL_SCORE_AKID 0x004
69 /* Have a delta CRL with valid times */
71 #define CRL_SCORE_TIME_DELTA 0x002
73 static int build_chain(X509_STORE_CTX *ctx);
74 static int verify_chain(X509_STORE_CTX *ctx);
75 static int dane_verify(X509_STORE_CTX *ctx);
76 static int null_callback(int ok, X509_STORE_CTX *e);
77 static int check_issued(X509_STORE_CTX *ctx, X509 *x, X509 *issuer);
78 static X509 *find_issuer(X509_STORE_CTX *ctx, STACK_OF(X509) *sk, X509 *x);
79 static int check_chain_extensions(X509_STORE_CTX *ctx);
80 static int check_name_constraints(X509_STORE_CTX *ctx);
81 static int check_id(X509_STORE_CTX *ctx);
82 static int check_trust(X509_STORE_CTX *ctx, int num_untrusted);
83 static int check_revocation(X509_STORE_CTX *ctx);
84 static int check_cert(X509_STORE_CTX *ctx);
85 static int check_policy(X509_STORE_CTX *ctx);
86 static int get_issuer_sk(X509 **issuer, X509_STORE_CTX *ctx, X509 *x);
87 static int check_dane_issuer(X509_STORE_CTX *ctx, int depth);
88 static int check_key_level(X509_STORE_CTX *ctx, X509 *cert);
89 static int check_sig_level(X509_STORE_CTX *ctx, X509 *cert);
91 static int get_crl_score(X509_STORE_CTX *ctx, X509 **pissuer,
92 unsigned int *preasons, X509_CRL *crl, X509 *x);
93 static int get_crl_delta(X509_STORE_CTX *ctx,
94 X509_CRL **pcrl, X509_CRL **pdcrl, X509 *x);
95 static void get_delta_sk(X509_STORE_CTX *ctx, X509_CRL **dcrl,
96 int *pcrl_score, X509_CRL *base,
97 STACK_OF(X509_CRL) *crls);
98 static void crl_akid_check(X509_STORE_CTX *ctx, X509_CRL *crl, X509 **pissuer,
100 static int crl_crldp_check(X509 *x, X509_CRL *crl, int crl_score,
101 unsigned int *preasons);
102 static int check_crl_path(X509_STORE_CTX *ctx, X509 *x);
103 static int check_crl_chain(X509_STORE_CTX *ctx,
104 STACK_OF(X509) *cert_path,
105 STACK_OF(X509) *crl_path);
107 static int internal_verify(X509_STORE_CTX *ctx);
109 static int null_callback(int ok, X509_STORE_CTX *e)
114 /* Return 1 is a certificate is self signed, 0 if not, or -1 on error */
115 static int cert_self_signed(X509_STORE_CTX *ctx, X509 *x)
117 if (!X509v3_cache_extensions(x, ctx->libctx, ctx->propq))
120 if (x->ex_flags & EXFLAG_SS)
126 /* Given a certificate try and find an exact match in the store */
128 static X509 *lookup_cert_match(X509_STORE_CTX *ctx, X509 *x)
130 STACK_OF(X509) *certs;
133 /* Lookup all certs with matching subject name */
134 certs = ctx->lookup_certs(ctx, X509_get_subject_name(x));
137 /* Look for exact match */
138 for (i = 0; i < sk_X509_num(certs); i++) {
139 xtmp = sk_X509_value(certs, i);
140 if (!X509_cmp(xtmp, x))
143 if (i < sk_X509_num(certs))
147 sk_X509_pop_free(certs, X509_free);
152 * Inform the verify callback of an error.
153 * If B<x> is not NULL it is the error cert, otherwise use the chain cert at
155 * If B<err> is not X509_V_OK, that's the error value, otherwise leave
156 * unchanged (presumably set by the caller).
158 * Returns 0 to abort verification with an error, non-zero to continue.
160 static int verify_cb_cert(X509_STORE_CTX *ctx, X509 *x, int depth, int err)
162 ctx->error_depth = depth;
163 ctx->current_cert = (x != NULL) ? x : sk_X509_value(ctx->chain, depth);
164 if (err != X509_V_OK)
166 return ctx->verify_cb(0, ctx);
170 * Inform the verify callback of an error, CRL-specific variant. Here, the
171 * error depth and certificate are already set, we just specify the error
174 * Returns 0 to abort verification with an error, non-zero to continue.
176 static int verify_cb_crl(X509_STORE_CTX *ctx, int err)
179 return ctx->verify_cb(0, ctx);
182 static int check_auth_level(X509_STORE_CTX *ctx)
185 int num = sk_X509_num(ctx->chain);
187 if (ctx->param->auth_level <= 0)
190 for (i = 0; i < num; ++i) {
191 X509 *cert = sk_X509_value(ctx->chain, i);
194 * We've already checked the security of the leaf key, so here we only
195 * check the security of issuer keys.
197 if (i > 0 && !check_key_level(ctx, cert) &&
198 verify_cb_cert(ctx, cert, i, X509_V_ERR_CA_KEY_TOO_SMALL) == 0)
201 * We also check the signature algorithm security of all certificates
202 * except those of the trust anchor at index num-1.
204 if (i < num - 1 && !check_sig_level(ctx, cert) &&
205 verify_cb_cert(ctx, cert, i, X509_V_ERR_CA_MD_TOO_WEAK) == 0)
211 static int verify_chain(X509_STORE_CTX *ctx)
217 * Before either returning with an error, or continuing with CRL checks,
218 * instantiate chain public key parameters.
220 if ((ok = build_chain(ctx)) == 0 ||
221 (ok = check_chain_extensions(ctx)) == 0 ||
222 (ok = check_auth_level(ctx)) == 0 ||
223 (ok = check_id(ctx)) == 0 || 1)
224 X509_get_pubkey_parameters(NULL, ctx->chain);
225 if (ok == 0 || (ok = ctx->check_revocation(ctx)) == 0)
228 err = X509_chain_check_suiteb(&ctx->error_depth, NULL, ctx->chain,
230 if (err != X509_V_OK) {
231 if ((ok = verify_cb_cert(ctx, NULL, ctx->error_depth, err)) == 0)
235 /* Verify chain signatures and expiration times */
236 ok = (ctx->verify != NULL) ? ctx->verify(ctx) : internal_verify(ctx);
240 if ((ok = check_name_constraints(ctx)) == 0)
243 #ifndef OPENSSL_NO_RFC3779
244 /* RFC 3779 path validation, now that CRL check has been done */
245 if ((ok = X509v3_asid_validate_path(ctx)) == 0)
247 if ((ok = X509v3_addr_validate_path(ctx)) == 0)
251 /* If we get this far evaluate policies */
252 if (ctx->param->flags & X509_V_FLAG_POLICY_CHECK)
253 ok = ctx->check_policy(ctx);
257 int X509_verify_cert(X509_STORE_CTX *ctx)
259 SSL_DANE *dane = ctx->dane;
262 if (ctx->cert == NULL) {
263 X509err(X509_F_X509_VERIFY_CERT, X509_R_NO_CERT_SET_FOR_US_TO_VERIFY);
264 ctx->error = X509_V_ERR_INVALID_CALL;
268 if (ctx->chain != NULL) {
270 * This X509_STORE_CTX has already been used to verify a cert. We
271 * cannot do another one.
273 X509err(X509_F_X509_VERIFY_CERT, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
274 ctx->error = X509_V_ERR_INVALID_CALL;
279 * first we make sure the chain we are going to build is present and that
280 * the first entry is in place
282 if (((ctx->chain = sk_X509_new_null()) == NULL) ||
283 (!sk_X509_push(ctx->chain, ctx->cert))) {
284 X509err(X509_F_X509_VERIFY_CERT, ERR_R_MALLOC_FAILURE);
285 ctx->error = X509_V_ERR_OUT_OF_MEM;
288 X509_up_ref(ctx->cert);
289 ctx->num_untrusted = 1;
291 /* If the peer's public key is too weak, we can stop early. */
292 if (!check_key_level(ctx, ctx->cert) &&
293 !verify_cb_cert(ctx, ctx->cert, 0, X509_V_ERR_EE_KEY_TOO_SMALL))
296 if (DANETLS_ENABLED(dane))
297 ret = dane_verify(ctx);
299 ret = verify_chain(ctx);
302 * Safety-net. If we are returning an error, we must also set ctx->error,
303 * so that the chain is not considered verified should the error be ignored
304 * (e.g. TLS with SSL_VERIFY_NONE).
306 if (ret <= 0 && ctx->error == X509_V_OK)
307 ctx->error = X509_V_ERR_UNSPECIFIED;
312 * Given a STACK_OF(X509) find the issuer of cert (if any)
314 static X509 *find_issuer(X509_STORE_CTX *ctx, STACK_OF(X509) *sk, X509 *x)
317 X509 *issuer, *rv = NULL;
319 for (i = 0; i < sk_X509_num(sk); i++) {
320 issuer = sk_X509_value(sk, i);
321 if (ctx->check_issued(ctx, x, issuer)) {
323 if (x509_check_cert_time(ctx, rv, -1))
330 /* Given a possible certificate and issuer check them */
332 static int check_issued(X509_STORE_CTX *ctx, X509 *x, X509 *issuer)
338 ss = cert_self_signed(ctx, x);
344 ret = x509_check_issued_int(issuer, x, ctx->libctx, ctx->propq);
345 if (ret == X509_V_OK) {
349 ss = cert_self_signed(ctx, x);
353 /* Special case: single self signed certificate */
354 if (ss > 0 && sk_X509_num(ctx->chain) == 1)
356 for (i = 0; i < sk_X509_num(ctx->chain); i++) {
357 ch = sk_X509_value(ctx->chain, i);
358 if (ch == issuer || !X509_cmp(ch, issuer)) {
359 ret = X509_V_ERR_PATH_LOOP;
365 return (ret == X509_V_OK);
368 /* Alternative lookup method: look from a STACK stored in other_ctx */
370 static int get_issuer_sk(X509 **issuer, X509_STORE_CTX *ctx, X509 *x)
372 *issuer = find_issuer(ctx, ctx->other_ctx, x);
374 X509_up_ref(*issuer);
380 static STACK_OF(X509) *lookup_certs_sk(X509_STORE_CTX *ctx,
383 STACK_OF(X509) *sk = NULL;
387 for (i = 0; i < sk_X509_num(ctx->other_ctx); i++) {
388 x = sk_X509_value(ctx->other_ctx, i);
389 if (X509_NAME_cmp(nm, X509_get_subject_name(x)) == 0) {
391 sk = sk_X509_new_null();
392 if (sk == NULL || sk_X509_push(sk, x) == 0) {
393 sk_X509_pop_free(sk, X509_free);
394 X509err(X509_F_LOOKUP_CERTS_SK, ERR_R_MALLOC_FAILURE);
395 ctx->error = X509_V_ERR_OUT_OF_MEM;
405 * Check EE or CA certificate purpose. For trusted certificates explicit local
406 * auxiliary trust can be used to override EKU-restrictions.
408 static int check_purpose(X509_STORE_CTX *ctx, X509 *x, int purpose, int depth,
411 int tr_ok = X509_TRUST_UNTRUSTED;
414 * For trusted certificates we want to see whether any auxiliary trust
415 * settings trump the purpose constraints.
417 * This is complicated by the fact that the trust ordinals in
418 * ctx->param->trust are entirely independent of the purpose ordinals in
419 * ctx->param->purpose!
421 * What connects them is their mutual initialization via calls from
422 * X509_STORE_CTX_set_default() into X509_VERIFY_PARAM_lookup() which sets
423 * related values of both param->trust and param->purpose. It is however
424 * typically possible to infer associated trust values from a purpose value
425 * via the X509_PURPOSE API.
427 * Therefore, we can only check for trust overrides when the purpose we're
428 * checking is the same as ctx->param->purpose and ctx->param->trust is
431 if (depth >= ctx->num_untrusted && purpose == ctx->param->purpose)
432 tr_ok = X509_check_trust(x, ctx->param->trust, X509_TRUST_NO_SS_COMPAT);
435 case X509_TRUST_TRUSTED:
437 case X509_TRUST_REJECTED:
440 switch (X509_check_purpose(x, purpose, must_be_ca > 0)) {
446 if ((ctx->param->flags & X509_V_FLAG_X509_STRICT) == 0)
452 return verify_cb_cert(ctx, x, depth, X509_V_ERR_INVALID_PURPOSE);
456 * Check a certificate chains extensions for consistency with the supplied
460 static int check_chain_extensions(X509_STORE_CTX *ctx)
462 int i, must_be_ca, plen = 0;
464 int proxy_path_length = 0;
466 int allow_proxy_certs;
467 int num = sk_X509_num(ctx->chain);
470 * must_be_ca can have 1 of 3 values:
471 * -1: we accept both CA and non-CA certificates, to allow direct
472 * use of self-signed certificates (which are marked as CA).
473 * 0: we only accept non-CA certificates. This is currently not
474 * used, but the possibility is present for future extensions.
475 * 1: we only accept CA certificates. This is currently used for
476 * all certificates in the chain except the leaf certificate.
480 /* CRL path validation */
482 allow_proxy_certs = 0;
483 purpose = X509_PURPOSE_CRL_SIGN;
486 ! !(ctx->param->flags & X509_V_FLAG_ALLOW_PROXY_CERTS);
487 purpose = ctx->param->purpose;
490 for (i = 0; i < num; i++) {
492 x = sk_X509_value(ctx->chain, i);
493 if (!(ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL)
494 && (x->ex_flags & EXFLAG_CRITICAL)) {
495 if (!verify_cb_cert(ctx, x, i,
496 X509_V_ERR_UNHANDLED_CRITICAL_EXTENSION))
499 if (!allow_proxy_certs && (x->ex_flags & EXFLAG_PROXY)) {
500 if (!verify_cb_cert(ctx, x, i,
501 X509_V_ERR_PROXY_CERTIFICATES_NOT_ALLOWED))
504 ret = X509_check_ca(x);
505 switch (must_be_ca) {
507 if ((ctx->param->flags & X509_V_FLAG_X509_STRICT)
508 && (ret != 1) && (ret != 0)) {
510 ctx->error = X509_V_ERR_INVALID_CA;
517 ctx->error = X509_V_ERR_INVALID_NON_CA;
522 /* X509_V_FLAG_X509_STRICT is implicit for intermediate CAs */
524 || ((i + 1 < num || ctx->param->flags & X509_V_FLAG_X509_STRICT)
527 ctx->error = X509_V_ERR_INVALID_CA;
532 if ((x->ex_flags & EXFLAG_CA) == 0
533 && x->ex_pathlen != -1
534 && (ctx->param->flags & X509_V_FLAG_X509_STRICT)) {
535 ctx->error = X509_V_ERR_INVALID_EXTENSION;
538 if (ret == 0 && !verify_cb_cert(ctx, x, i, X509_V_OK))
540 /* check_purpose() makes the callback as needed */
541 if (purpose > 0 && !check_purpose(ctx, x, purpose, i, must_be_ca))
544 if ((i > 1) && (x->ex_pathlen != -1)
545 && (plen > (x->ex_pathlen + proxy_path_length))) {
546 if (!verify_cb_cert(ctx, x, i, X509_V_ERR_PATH_LENGTH_EXCEEDED))
549 /* Increment path length if not a self issued intermediate CA */
550 if (i > 0 && (x->ex_flags & EXFLAG_SI) == 0)
553 * If this certificate is a proxy certificate, the next certificate
554 * must be another proxy certificate or a EE certificate. If not,
555 * the next certificate must be a CA certificate.
557 if (x->ex_flags & EXFLAG_PROXY) {
559 * RFC3820, 4.1.3 (b)(1) stipulates that if pCPathLengthConstraint
560 * is less than max_path_length, the former should be copied to
561 * the latter, and 4.1.4 (a) stipulates that max_path_length
562 * should be verified to be larger than zero and decrement it.
564 * Because we're checking the certs in the reverse order, we start
565 * with verifying that proxy_path_length isn't larger than pcPLC,
566 * and copy the latter to the former if it is, and finally,
567 * increment proxy_path_length.
569 if (x->ex_pcpathlen != -1) {
570 if (proxy_path_length > x->ex_pcpathlen) {
571 if (!verify_cb_cert(ctx, x, i,
572 X509_V_ERR_PROXY_PATH_LENGTH_EXCEEDED))
575 proxy_path_length = x->ex_pcpathlen;
585 static int has_san_id(X509 *x, int gtype)
589 GENERAL_NAMES *gs = X509_get_ext_d2i(x, NID_subject_alt_name, NULL, NULL);
594 for (i = 0; i < sk_GENERAL_NAME_num(gs); i++) {
595 GENERAL_NAME *g = sk_GENERAL_NAME_value(gs, i);
597 if (g->type == gtype) {
602 GENERAL_NAMES_free(gs);
606 static int check_name_constraints(X509_STORE_CTX *ctx)
610 /* Check name constraints for all certificates */
611 for (i = sk_X509_num(ctx->chain) - 1; i >= 0; i--) {
612 X509 *x = sk_X509_value(ctx->chain, i);
615 /* Ignore self issued certs unless last in chain */
616 if (i && (x->ex_flags & EXFLAG_SI))
620 * Proxy certificates policy has an extra constraint, where the
621 * certificate subject MUST be the issuer with a single CN entry
623 * (RFC 3820: 3.4, 4.1.3 (a)(4))
625 if (x->ex_flags & EXFLAG_PROXY) {
626 X509_NAME *tmpsubject = X509_get_subject_name(x);
627 X509_NAME *tmpissuer = X509_get_issuer_name(x);
628 X509_NAME_ENTRY *tmpentry = NULL;
629 int last_object_nid = 0;
631 int last_object_loc = X509_NAME_entry_count(tmpsubject) - 1;
633 /* Check that there are at least two RDNs */
634 if (last_object_loc < 1) {
635 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
636 goto proxy_name_done;
640 * Check that there is exactly one more RDN in subject as
641 * there is in issuer.
643 if (X509_NAME_entry_count(tmpsubject)
644 != X509_NAME_entry_count(tmpissuer) + 1) {
645 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
646 goto proxy_name_done;
650 * Check that the last subject component isn't part of a
653 if (X509_NAME_ENTRY_set(X509_NAME_get_entry(tmpsubject,
655 == X509_NAME_ENTRY_set(X509_NAME_get_entry(tmpsubject,
656 last_object_loc - 1))) {
657 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
658 goto proxy_name_done;
662 * Check that the last subject RDN is a commonName, and that
663 * all the previous RDNs match the issuer exactly
665 tmpsubject = X509_NAME_dup(tmpsubject);
666 if (tmpsubject == NULL) {
667 X509err(X509_F_CHECK_NAME_CONSTRAINTS, ERR_R_MALLOC_FAILURE);
668 ctx->error = X509_V_ERR_OUT_OF_MEM;
673 X509_NAME_delete_entry(tmpsubject, last_object_loc);
675 OBJ_obj2nid(X509_NAME_ENTRY_get_object(tmpentry));
677 if (last_object_nid != NID_commonName
678 || X509_NAME_cmp(tmpsubject, tmpissuer) != 0) {
679 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
682 X509_NAME_ENTRY_free(tmpentry);
683 X509_NAME_free(tmpsubject);
687 && !verify_cb_cert(ctx, x, i, err))
692 * Check against constraints for all certificates higher in chain
693 * including trust anchor. Trust anchor not strictly speaking needed
694 * but if it includes constraints it is to be assumed it expects them
697 for (j = sk_X509_num(ctx->chain) - 1; j > i; j--) {
698 NAME_CONSTRAINTS *nc = sk_X509_value(ctx->chain, j)->nc;
701 int rv = NAME_CONSTRAINTS_check(x, nc);
703 /* If EE certificate check commonName too */
704 if (rv == X509_V_OK && i == 0
705 && (ctx->param->hostflags
706 & X509_CHECK_FLAG_NEVER_CHECK_SUBJECT) == 0
707 && ((ctx->param->hostflags
708 & X509_CHECK_FLAG_ALWAYS_CHECK_SUBJECT) != 0
709 || !has_san_id(x, GEN_DNS)))
710 rv = NAME_CONSTRAINTS_check_CN(x, nc);
715 case X509_V_ERR_OUT_OF_MEM:
718 if (!verify_cb_cert(ctx, x, i, rv))
728 static int check_id_error(X509_STORE_CTX *ctx, int errcode)
730 return verify_cb_cert(ctx, ctx->cert, 0, errcode);
733 static int check_hosts(X509 *x, X509_VERIFY_PARAM *vpm)
736 int n = sk_OPENSSL_STRING_num(vpm->hosts);
739 if (vpm->peername != NULL) {
740 OPENSSL_free(vpm->peername);
741 vpm->peername = NULL;
743 for (i = 0; i < n; ++i) {
744 name = sk_OPENSSL_STRING_value(vpm->hosts, i);
745 if (X509_check_host(x, name, 0, vpm->hostflags, &vpm->peername) > 0)
751 static int check_id(X509_STORE_CTX *ctx)
753 X509_VERIFY_PARAM *vpm = ctx->param;
755 if (vpm->hosts && check_hosts(x, vpm) <= 0) {
756 if (!check_id_error(ctx, X509_V_ERR_HOSTNAME_MISMATCH))
759 if (vpm->email && X509_check_email(x, vpm->email, vpm->emaillen, 0) <= 0) {
760 if (!check_id_error(ctx, X509_V_ERR_EMAIL_MISMATCH))
763 if (vpm->ip && X509_check_ip(x, vpm->ip, vpm->iplen, 0) <= 0) {
764 if (!check_id_error(ctx, X509_V_ERR_IP_ADDRESS_MISMATCH))
770 static int check_trust(X509_STORE_CTX *ctx, int num_untrusted)
775 SSL_DANE *dane = ctx->dane;
776 int num = sk_X509_num(ctx->chain);
780 * Check for a DANE issuer at depth 1 or greater, if it is a DANE-TA(2)
781 * match, we're done, otherwise we'll merely record the match depth.
783 if (DANETLS_HAS_TA(dane) && num_untrusted > 0 && num_untrusted < num) {
784 switch (trust = check_dane_issuer(ctx, num_untrusted)) {
785 case X509_TRUST_TRUSTED:
786 case X509_TRUST_REJECTED:
792 * Check trusted certificates in chain at depth num_untrusted and up.
793 * Note, that depths 0..num_untrusted-1 may also contain trusted
794 * certificates, but the caller is expected to have already checked those,
795 * and wants to incrementally check just any added since.
797 for (i = num_untrusted; i < num; i++) {
798 x = sk_X509_value(ctx->chain, i);
799 trust = X509_check_trust(x, ctx->param->trust, 0);
800 /* If explicitly trusted return trusted */
801 if (trust == X509_TRUST_TRUSTED)
803 if (trust == X509_TRUST_REJECTED)
808 * If we are looking at a trusted certificate, and accept partial chains,
809 * the chain is PKIX trusted.
811 if (num_untrusted < num) {
812 if (ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN)
814 return X509_TRUST_UNTRUSTED;
817 if (num_untrusted == num && ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) {
819 * Last-resort call with no new trusted certificates, check the leaf
820 * for a direct trust store match.
823 x = sk_X509_value(ctx->chain, i);
824 mx = lookup_cert_match(ctx, x);
826 return X509_TRUST_UNTRUSTED;
829 * Check explicit auxiliary trust/reject settings. If none are set,
830 * we'll accept X509_TRUST_UNTRUSTED when not self-signed.
832 trust = X509_check_trust(mx, ctx->param->trust, 0);
833 if (trust == X509_TRUST_REJECTED) {
838 /* Replace leaf with trusted match */
839 (void) sk_X509_set(ctx->chain, 0, mx);
841 ctx->num_untrusted = 0;
846 * If no trusted certs in chain at all return untrusted and allow
847 * standard (no issuer cert) etc errors to be indicated.
849 return X509_TRUST_UNTRUSTED;
852 if (!verify_cb_cert(ctx, x, i, X509_V_ERR_CERT_REJECTED))
853 return X509_TRUST_REJECTED;
854 return X509_TRUST_UNTRUSTED;
857 if (!DANETLS_ENABLED(dane))
858 return X509_TRUST_TRUSTED;
860 dane->pdpth = num_untrusted;
861 /* With DANE, PKIX alone is not trusted until we have both */
862 if (dane->mdpth >= 0)
863 return X509_TRUST_TRUSTED;
864 return X509_TRUST_UNTRUSTED;
867 static int check_revocation(X509_STORE_CTX *ctx)
869 int i = 0, last = 0, ok = 0;
870 if (!(ctx->param->flags & X509_V_FLAG_CRL_CHECK))
872 if (ctx->param->flags & X509_V_FLAG_CRL_CHECK_ALL)
873 last = sk_X509_num(ctx->chain) - 1;
875 /* If checking CRL paths this isn't the EE certificate */
880 for (i = 0; i <= last; i++) {
881 ctx->error_depth = i;
882 ok = check_cert(ctx);
889 static int check_cert(X509_STORE_CTX *ctx)
891 X509_CRL *crl = NULL, *dcrl = NULL;
893 int cnum = ctx->error_depth;
894 X509 *x = sk_X509_value(ctx->chain, cnum);
896 ctx->current_cert = x;
897 ctx->current_issuer = NULL;
898 ctx->current_crl_score = 0;
899 ctx->current_reasons = 0;
901 if (x->ex_flags & EXFLAG_PROXY)
904 while (ctx->current_reasons != CRLDP_ALL_REASONS) {
905 unsigned int last_reasons = ctx->current_reasons;
907 /* Try to retrieve relevant CRL */
909 ok = ctx->get_crl(ctx, &crl, x);
911 ok = get_crl_delta(ctx, &crl, &dcrl, x);
913 * If error looking up CRL, nothing we can do except notify callback
916 ok = verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL);
919 ctx->current_crl = crl;
920 ok = ctx->check_crl(ctx, crl);
925 ok = ctx->check_crl(ctx, dcrl);
928 ok = ctx->cert_crl(ctx, dcrl, x);
934 /* Don't look in full CRL if delta reason is removefromCRL */
936 ok = ctx->cert_crl(ctx, crl, x);
946 * If reasons not updated we won't get anywhere by another iteration,
949 if (last_reasons == ctx->current_reasons) {
950 ok = verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL);
958 ctx->current_crl = NULL;
962 /* Check CRL times against values in X509_STORE_CTX */
964 static int check_crl_time(X509_STORE_CTX *ctx, X509_CRL *crl, int notify)
970 ctx->current_crl = crl;
971 if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME)
972 ptime = &ctx->param->check_time;
973 else if (ctx->param->flags & X509_V_FLAG_NO_CHECK_TIME)
978 i = X509_cmp_time(X509_CRL_get0_lastUpdate(crl), ptime);
982 if (!verify_cb_crl(ctx, X509_V_ERR_ERROR_IN_CRL_LAST_UPDATE_FIELD))
989 if (!verify_cb_crl(ctx, X509_V_ERR_CRL_NOT_YET_VALID))
993 if (X509_CRL_get0_nextUpdate(crl)) {
994 i = X509_cmp_time(X509_CRL_get0_nextUpdate(crl), ptime);
999 if (!verify_cb_crl(ctx, X509_V_ERR_ERROR_IN_CRL_NEXT_UPDATE_FIELD))
1002 /* Ignore expiry of base CRL is delta is valid */
1003 if ((i < 0) && !(ctx->current_crl_score & CRL_SCORE_TIME_DELTA)) {
1006 if (!verify_cb_crl(ctx, X509_V_ERR_CRL_HAS_EXPIRED))
1012 ctx->current_crl = NULL;
1017 static int get_crl_sk(X509_STORE_CTX *ctx, X509_CRL **pcrl, X509_CRL **pdcrl,
1018 X509 **pissuer, int *pscore, unsigned int *preasons,
1019 STACK_OF(X509_CRL) *crls)
1021 int i, crl_score, best_score = *pscore;
1022 unsigned int reasons, best_reasons = 0;
1023 X509 *x = ctx->current_cert;
1024 X509_CRL *crl, *best_crl = NULL;
1025 X509 *crl_issuer = NULL, *best_crl_issuer = NULL;
1027 for (i = 0; i < sk_X509_CRL_num(crls); i++) {
1028 crl = sk_X509_CRL_value(crls, i);
1029 reasons = *preasons;
1030 crl_score = get_crl_score(ctx, &crl_issuer, &reasons, crl, x);
1031 if (crl_score < best_score || crl_score == 0)
1033 /* If current CRL is equivalent use it if it is newer */
1034 if (crl_score == best_score && best_crl != NULL) {
1036 if (ASN1_TIME_diff(&day, &sec, X509_CRL_get0_lastUpdate(best_crl),
1037 X509_CRL_get0_lastUpdate(crl)) == 0)
1040 * ASN1_TIME_diff never returns inconsistent signs for |day|
1043 if (day <= 0 && sec <= 0)
1047 best_crl_issuer = crl_issuer;
1048 best_score = crl_score;
1049 best_reasons = reasons;
1053 X509_CRL_free(*pcrl);
1055 *pissuer = best_crl_issuer;
1056 *pscore = best_score;
1057 *preasons = best_reasons;
1058 X509_CRL_up_ref(best_crl);
1059 X509_CRL_free(*pdcrl);
1061 get_delta_sk(ctx, pdcrl, pscore, best_crl, crls);
1064 if (best_score >= CRL_SCORE_VALID)
1071 * Compare two CRL extensions for delta checking purposes. They should be
1072 * both present or both absent. If both present all fields must be identical.
1075 static int crl_extension_match(X509_CRL *a, X509_CRL *b, int nid)
1077 ASN1_OCTET_STRING *exta, *extb;
1079 i = X509_CRL_get_ext_by_NID(a, nid, -1);
1081 /* Can't have multiple occurrences */
1082 if (X509_CRL_get_ext_by_NID(a, nid, i) != -1)
1084 exta = X509_EXTENSION_get_data(X509_CRL_get_ext(a, i));
1088 i = X509_CRL_get_ext_by_NID(b, nid, -1);
1092 if (X509_CRL_get_ext_by_NID(b, nid, i) != -1)
1094 extb = X509_EXTENSION_get_data(X509_CRL_get_ext(b, i));
1104 if (ASN1_OCTET_STRING_cmp(exta, extb))
1110 /* See if a base and delta are compatible */
1112 static int check_delta_base(X509_CRL *delta, X509_CRL *base)
1114 /* Delta CRL must be a delta */
1115 if (!delta->base_crl_number)
1117 /* Base must have a CRL number */
1118 if (!base->crl_number)
1120 /* Issuer names must match */
1121 if (X509_NAME_cmp(X509_CRL_get_issuer(base), X509_CRL_get_issuer(delta)))
1123 /* AKID and IDP must match */
1124 if (!crl_extension_match(delta, base, NID_authority_key_identifier))
1126 if (!crl_extension_match(delta, base, NID_issuing_distribution_point))
1128 /* Delta CRL base number must not exceed Full CRL number. */
1129 if (ASN1_INTEGER_cmp(delta->base_crl_number, base->crl_number) > 0)
1131 /* Delta CRL number must exceed full CRL number */
1132 if (ASN1_INTEGER_cmp(delta->crl_number, base->crl_number) > 0)
1138 * For a given base CRL find a delta... maybe extend to delta scoring or
1139 * retrieve a chain of deltas...
1142 static void get_delta_sk(X509_STORE_CTX *ctx, X509_CRL **dcrl, int *pscore,
1143 X509_CRL *base, STACK_OF(X509_CRL) *crls)
1147 if (!(ctx->param->flags & X509_V_FLAG_USE_DELTAS))
1149 if (!((ctx->current_cert->ex_flags | base->flags) & EXFLAG_FRESHEST))
1151 for (i = 0; i < sk_X509_CRL_num(crls); i++) {
1152 delta = sk_X509_CRL_value(crls, i);
1153 if (check_delta_base(delta, base)) {
1154 if (check_crl_time(ctx, delta, 0))
1155 *pscore |= CRL_SCORE_TIME_DELTA;
1156 X509_CRL_up_ref(delta);
1165 * For a given CRL return how suitable it is for the supplied certificate
1166 * 'x'. The return value is a mask of several criteria. If the issuer is not
1167 * the certificate issuer this is returned in *pissuer. The reasons mask is
1168 * also used to determine if the CRL is suitable: if no new reasons the CRL
1169 * is rejected, otherwise reasons is updated.
1172 static int get_crl_score(X509_STORE_CTX *ctx, X509 **pissuer,
1173 unsigned int *preasons, X509_CRL *crl, X509 *x)
1177 unsigned int tmp_reasons = *preasons, crl_reasons;
1179 /* First see if we can reject CRL straight away */
1181 /* Invalid IDP cannot be processed */
1182 if (crl->idp_flags & IDP_INVALID)
1184 /* Reason codes or indirect CRLs need extended CRL support */
1185 if (!(ctx->param->flags & X509_V_FLAG_EXTENDED_CRL_SUPPORT)) {
1186 if (crl->idp_flags & (IDP_INDIRECT | IDP_REASONS))
1188 } else if (crl->idp_flags & IDP_REASONS) {
1189 /* If no new reasons reject */
1190 if (!(crl->idp_reasons & ~tmp_reasons))
1193 /* Don't process deltas at this stage */
1194 else if (crl->base_crl_number)
1196 /* If issuer name doesn't match certificate need indirect CRL */
1197 if (X509_NAME_cmp(X509_get_issuer_name(x), X509_CRL_get_issuer(crl))) {
1198 if (!(crl->idp_flags & IDP_INDIRECT))
1201 crl_score |= CRL_SCORE_ISSUER_NAME;
1203 if (!(crl->flags & EXFLAG_CRITICAL))
1204 crl_score |= CRL_SCORE_NOCRITICAL;
1207 if (check_crl_time(ctx, crl, 0))
1208 crl_score |= CRL_SCORE_TIME;
1210 /* Check authority key ID and locate certificate issuer */
1211 crl_akid_check(ctx, crl, pissuer, &crl_score);
1213 /* If we can't locate certificate issuer at this point forget it */
1215 if (!(crl_score & CRL_SCORE_AKID))
1218 /* Check cert for matching CRL distribution points */
1220 if (crl_crldp_check(x, crl, crl_score, &crl_reasons)) {
1221 /* If no new reasons reject */
1222 if (!(crl_reasons & ~tmp_reasons))
1224 tmp_reasons |= crl_reasons;
1225 crl_score |= CRL_SCORE_SCOPE;
1228 *preasons = tmp_reasons;
1234 static void crl_akid_check(X509_STORE_CTX *ctx, X509_CRL *crl,
1235 X509 **pissuer, int *pcrl_score)
1237 X509 *crl_issuer = NULL;
1238 const X509_NAME *cnm = X509_CRL_get_issuer(crl);
1239 int cidx = ctx->error_depth;
1242 if (cidx != sk_X509_num(ctx->chain) - 1)
1245 crl_issuer = sk_X509_value(ctx->chain, cidx);
1247 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1248 if (*pcrl_score & CRL_SCORE_ISSUER_NAME) {
1249 *pcrl_score |= CRL_SCORE_AKID | CRL_SCORE_ISSUER_CERT;
1250 *pissuer = crl_issuer;
1255 for (cidx++; cidx < sk_X509_num(ctx->chain); cidx++) {
1256 crl_issuer = sk_X509_value(ctx->chain, cidx);
1257 if (X509_NAME_cmp(X509_get_subject_name(crl_issuer), cnm))
1259 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1260 *pcrl_score |= CRL_SCORE_AKID | CRL_SCORE_SAME_PATH;
1261 *pissuer = crl_issuer;
1266 /* Anything else needs extended CRL support */
1268 if (!(ctx->param->flags & X509_V_FLAG_EXTENDED_CRL_SUPPORT))
1272 * Otherwise the CRL issuer is not on the path. Look for it in the set of
1273 * untrusted certificates.
1275 for (i = 0; i < sk_X509_num(ctx->untrusted); i++) {
1276 crl_issuer = sk_X509_value(ctx->untrusted, i);
1277 if (X509_NAME_cmp(X509_get_subject_name(crl_issuer), cnm))
1279 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1280 *pissuer = crl_issuer;
1281 *pcrl_score |= CRL_SCORE_AKID;
1288 * Check the path of a CRL issuer certificate. This creates a new
1289 * X509_STORE_CTX and populates it with most of the parameters from the
1290 * parent. This could be optimised somewhat since a lot of path checking will
1291 * be duplicated by the parent, but this will rarely be used in practice.
1294 static int check_crl_path(X509_STORE_CTX *ctx, X509 *x)
1296 X509_STORE_CTX crl_ctx;
1299 /* Don't allow recursive CRL path validation */
1302 if (!X509_STORE_CTX_init(&crl_ctx, ctx->store, x, ctx->untrusted))
1305 crl_ctx.crls = ctx->crls;
1306 /* Copy verify params across */
1307 X509_STORE_CTX_set0_param(&crl_ctx, ctx->param);
1309 crl_ctx.parent = ctx;
1310 crl_ctx.verify_cb = ctx->verify_cb;
1312 /* Verify CRL issuer */
1313 ret = X509_verify_cert(&crl_ctx);
1317 /* Check chain is acceptable */
1318 ret = check_crl_chain(ctx, ctx->chain, crl_ctx.chain);
1320 X509_STORE_CTX_cleanup(&crl_ctx);
1325 * RFC3280 says nothing about the relationship between CRL path and
1326 * certificate path, which could lead to situations where a certificate could
1327 * be revoked or validated by a CA not authorised to do so. RFC5280 is more
1328 * strict and states that the two paths must end in the same trust anchor,
1329 * though some discussions remain... until this is resolved we use the
1333 static int check_crl_chain(X509_STORE_CTX *ctx,
1334 STACK_OF(X509) *cert_path,
1335 STACK_OF(X509) *crl_path)
1337 X509 *cert_ta, *crl_ta;
1338 cert_ta = sk_X509_value(cert_path, sk_X509_num(cert_path) - 1);
1339 crl_ta = sk_X509_value(crl_path, sk_X509_num(crl_path) - 1);
1340 if (!X509_cmp(cert_ta, crl_ta))
1346 * Check for match between two dist point names: three separate cases.
1347 * 1. Both are relative names and compare X509_NAME types.
1348 * 2. One full, one relative. Compare X509_NAME to GENERAL_NAMES.
1349 * 3. Both are full names and compare two GENERAL_NAMES.
1350 * 4. One is NULL: automatic match.
1353 static int idp_check_dp(DIST_POINT_NAME *a, DIST_POINT_NAME *b)
1355 X509_NAME *nm = NULL;
1356 GENERAL_NAMES *gens = NULL;
1357 GENERAL_NAME *gena, *genb;
1364 /* Case 1: two X509_NAME */
1368 if (!X509_NAME_cmp(a->dpname, b->dpname))
1373 /* Case 2: set name and GENERAL_NAMES appropriately */
1375 gens = b->name.fullname;
1376 } else if (b->type == 1) {
1379 /* Case 2: set name and GENERAL_NAMES appropriately */
1380 gens = a->name.fullname;
1384 /* Handle case 2 with one GENERAL_NAMES and one X509_NAME */
1386 for (i = 0; i < sk_GENERAL_NAME_num(gens); i++) {
1387 gena = sk_GENERAL_NAME_value(gens, i);
1388 if (gena->type != GEN_DIRNAME)
1390 if (!X509_NAME_cmp(nm, gena->d.directoryName))
1396 /* Else case 3: two GENERAL_NAMES */
1398 for (i = 0; i < sk_GENERAL_NAME_num(a->name.fullname); i++) {
1399 gena = sk_GENERAL_NAME_value(a->name.fullname, i);
1400 for (j = 0; j < sk_GENERAL_NAME_num(b->name.fullname); j++) {
1401 genb = sk_GENERAL_NAME_value(b->name.fullname, j);
1402 if (!GENERAL_NAME_cmp(gena, genb))
1411 static int crldp_check_crlissuer(DIST_POINT *dp, X509_CRL *crl, int crl_score)
1414 const X509_NAME *nm = X509_CRL_get_issuer(crl);
1415 /* If no CRLissuer return is successful iff don't need a match */
1417 return ! !(crl_score & CRL_SCORE_ISSUER_NAME);
1418 for (i = 0; i < sk_GENERAL_NAME_num(dp->CRLissuer); i++) {
1419 GENERAL_NAME *gen = sk_GENERAL_NAME_value(dp->CRLissuer, i);
1420 if (gen->type != GEN_DIRNAME)
1422 if (!X509_NAME_cmp(gen->d.directoryName, nm))
1428 /* Check CRLDP and IDP */
1430 static int crl_crldp_check(X509 *x, X509_CRL *crl, int crl_score,
1431 unsigned int *preasons)
1434 if (crl->idp_flags & IDP_ONLYATTR)
1436 if (x->ex_flags & EXFLAG_CA) {
1437 if (crl->idp_flags & IDP_ONLYUSER)
1440 if (crl->idp_flags & IDP_ONLYCA)
1443 *preasons = crl->idp_reasons;
1444 for (i = 0; i < sk_DIST_POINT_num(x->crldp); i++) {
1445 DIST_POINT *dp = sk_DIST_POINT_value(x->crldp, i);
1446 if (crldp_check_crlissuer(dp, crl, crl_score)) {
1447 if (!crl->idp || idp_check_dp(dp->distpoint, crl->idp->distpoint)) {
1448 *preasons &= dp->dp_reasons;
1453 if ((!crl->idp || !crl->idp->distpoint)
1454 && (crl_score & CRL_SCORE_ISSUER_NAME))
1460 * Retrieve CRL corresponding to current certificate. If deltas enabled try
1461 * to find a delta CRL too
1464 static int get_crl_delta(X509_STORE_CTX *ctx,
1465 X509_CRL **pcrl, X509_CRL **pdcrl, X509 *x)
1468 X509 *issuer = NULL;
1470 unsigned int reasons;
1471 X509_CRL *crl = NULL, *dcrl = NULL;
1472 STACK_OF(X509_CRL) *skcrl;
1473 const X509_NAME *nm = X509_get_issuer_name(x);
1475 reasons = ctx->current_reasons;
1476 ok = get_crl_sk(ctx, &crl, &dcrl,
1477 &issuer, &crl_score, &reasons, ctx->crls);
1481 /* Lookup CRLs from store */
1483 skcrl = ctx->lookup_crls(ctx, nm);
1485 /* If no CRLs found and a near match from get_crl_sk use that */
1489 get_crl_sk(ctx, &crl, &dcrl, &issuer, &crl_score, &reasons, skcrl);
1491 sk_X509_CRL_pop_free(skcrl, X509_CRL_free);
1494 /* If we got any kind of CRL use it and return success */
1496 ctx->current_issuer = issuer;
1497 ctx->current_crl_score = crl_score;
1498 ctx->current_reasons = reasons;
1506 /* Check CRL validity */
1507 static int check_crl(X509_STORE_CTX *ctx, X509_CRL *crl)
1509 X509 *issuer = NULL;
1510 EVP_PKEY *ikey = NULL;
1511 int cnum = ctx->error_depth;
1512 int chnum = sk_X509_num(ctx->chain) - 1;
1514 /* if we have an alternative CRL issuer cert use that */
1515 if (ctx->current_issuer)
1516 issuer = ctx->current_issuer;
1518 * Else find CRL issuer: if not last certificate then issuer is next
1519 * certificate in chain.
1521 else if (cnum < chnum)
1522 issuer = sk_X509_value(ctx->chain, cnum + 1);
1524 issuer = sk_X509_value(ctx->chain, chnum);
1525 /* If not self signed, can't check signature */
1526 if (!ctx->check_issued(ctx, issuer, issuer) &&
1527 !verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL_ISSUER))
1535 * Skip most tests for deltas because they have already been done
1537 if (!crl->base_crl_number) {
1538 /* Check for cRLSign bit if keyUsage present */
1539 if ((issuer->ex_flags & EXFLAG_KUSAGE) &&
1540 !(issuer->ex_kusage & KU_CRL_SIGN) &&
1541 !verify_cb_crl(ctx, X509_V_ERR_KEYUSAGE_NO_CRL_SIGN))
1544 if (!(ctx->current_crl_score & CRL_SCORE_SCOPE) &&
1545 !verify_cb_crl(ctx, X509_V_ERR_DIFFERENT_CRL_SCOPE))
1548 if (!(ctx->current_crl_score & CRL_SCORE_SAME_PATH) &&
1549 check_crl_path(ctx, ctx->current_issuer) <= 0 &&
1550 !verify_cb_crl(ctx, X509_V_ERR_CRL_PATH_VALIDATION_ERROR))
1553 if ((crl->idp_flags & IDP_INVALID) &&
1554 !verify_cb_crl(ctx, X509_V_ERR_INVALID_EXTENSION))
1558 if (!(ctx->current_crl_score & CRL_SCORE_TIME) &&
1559 !check_crl_time(ctx, crl, 1))
1562 /* Attempt to get issuer certificate public key */
1563 ikey = X509_get0_pubkey(issuer);
1566 !verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY))
1570 int rv = X509_CRL_check_suiteb(crl, ikey, ctx->param->flags);
1572 if (rv != X509_V_OK && !verify_cb_crl(ctx, rv))
1574 /* Verify CRL signature */
1575 if (X509_CRL_verify(crl, ikey) <= 0 &&
1576 !verify_cb_crl(ctx, X509_V_ERR_CRL_SIGNATURE_FAILURE))
1582 /* Check certificate against CRL */
1583 static int cert_crl(X509_STORE_CTX *ctx, X509_CRL *crl, X509 *x)
1588 * The rules changed for this... previously if a CRL contained unhandled
1589 * critical extensions it could still be used to indicate a certificate
1590 * was revoked. This has since been changed since critical extensions can
1591 * change the meaning of CRL entries.
1593 if (!(ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL)
1594 && (crl->flags & EXFLAG_CRITICAL) &&
1595 !verify_cb_crl(ctx, X509_V_ERR_UNHANDLED_CRITICAL_CRL_EXTENSION))
1598 * Look for serial number of certificate in CRL. If found, make sure
1599 * reason is not removeFromCRL.
1601 if (X509_CRL_get0_by_cert(crl, &rev, x)) {
1602 if (rev->reason == CRL_REASON_REMOVE_FROM_CRL)
1604 if (!verify_cb_crl(ctx, X509_V_ERR_CERT_REVOKED))
1611 static int check_policy(X509_STORE_CTX *ctx)
1618 * With DANE, the trust anchor might be a bare public key, not a
1619 * certificate! In that case our chain does not have the trust anchor
1620 * certificate as a top-most element. This comports well with RFC5280
1621 * chain verification, since there too, the trust anchor is not part of the
1622 * chain to be verified. In particular, X509_policy_check() does not look
1623 * at the TA cert, but assumes that it is present as the top-most chain
1624 * element. We therefore temporarily push a NULL cert onto the chain if it
1625 * was verified via a bare public key, and pop it off right after the
1626 * X509_policy_check() call.
1628 if (ctx->bare_ta_signed && !sk_X509_push(ctx->chain, NULL)) {
1629 X509err(X509_F_CHECK_POLICY, ERR_R_MALLOC_FAILURE);
1630 ctx->error = X509_V_ERR_OUT_OF_MEM;
1633 ret = X509_policy_check(&ctx->tree, &ctx->explicit_policy, ctx->chain,
1634 ctx->param->policies, ctx->param->flags);
1635 if (ctx->bare_ta_signed)
1636 sk_X509_pop(ctx->chain);
1638 if (ret == X509_PCY_TREE_INTERNAL) {
1639 X509err(X509_F_CHECK_POLICY, ERR_R_MALLOC_FAILURE);
1640 ctx->error = X509_V_ERR_OUT_OF_MEM;
1643 /* Invalid or inconsistent extensions */
1644 if (ret == X509_PCY_TREE_INVALID) {
1647 /* Locate certificates with bad extensions and notify callback. */
1648 for (i = 1; i < sk_X509_num(ctx->chain); i++) {
1649 X509 *x = sk_X509_value(ctx->chain, i);
1651 if (!(x->ex_flags & EXFLAG_INVALID_POLICY))
1653 if (!verify_cb_cert(ctx, x, i,
1654 X509_V_ERR_INVALID_POLICY_EXTENSION))
1659 if (ret == X509_PCY_TREE_FAILURE) {
1660 ctx->current_cert = NULL;
1661 ctx->error = X509_V_ERR_NO_EXPLICIT_POLICY;
1662 return ctx->verify_cb(0, ctx);
1664 if (ret != X509_PCY_TREE_VALID) {
1665 X509err(X509_F_CHECK_POLICY, ERR_R_INTERNAL_ERROR);
1669 if (ctx->param->flags & X509_V_FLAG_NOTIFY_POLICY) {
1670 ctx->current_cert = NULL;
1672 * Verification errors need to be "sticky", a callback may have allowed
1673 * an SSL handshake to continue despite an error, and we must then
1674 * remain in an error state. Therefore, we MUST NOT clear earlier
1675 * verification errors by setting the error to X509_V_OK.
1677 if (!ctx->verify_cb(2, ctx))
1685 * Check certificate validity times.
1686 * If depth >= 0, invoke verification callbacks on error, otherwise just return
1687 * the validation status.
1689 * Return 1 on success, 0 otherwise.
1691 int x509_check_cert_time(X509_STORE_CTX *ctx, X509 *x, int depth)
1696 if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME)
1697 ptime = &ctx->param->check_time;
1698 else if (ctx->param->flags & X509_V_FLAG_NO_CHECK_TIME)
1703 i = X509_cmp_time(X509_get0_notBefore(x), ptime);
1704 if (i >= 0 && depth < 0)
1706 if (i == 0 && !verify_cb_cert(ctx, x, depth,
1707 X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD))
1709 if (i > 0 && !verify_cb_cert(ctx, x, depth, X509_V_ERR_CERT_NOT_YET_VALID))
1712 i = X509_cmp_time(X509_get0_notAfter(x), ptime);
1713 if (i <= 0 && depth < 0)
1715 if (i == 0 && !verify_cb_cert(ctx, x, depth,
1716 X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD))
1718 if (i < 0 && !verify_cb_cert(ctx, x, depth, X509_V_ERR_CERT_HAS_EXPIRED))
1723 static int internal_verify(X509_STORE_CTX *ctx)
1725 int n = sk_X509_num(ctx->chain) - 1;
1726 X509 *xi = sk_X509_value(ctx->chain, n);
1730 * With DANE-verified bare public key TA signatures, it remains only to
1731 * check the timestamps of the top certificate. We report the issuer as
1732 * NULL, since all we have is a bare key.
1734 if (ctx->bare_ta_signed) {
1740 if (ctx->check_issued(ctx, xi, xi))
1743 if (ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) {
1748 return verify_cb_cert(ctx, xi, 0,
1749 X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE);
1751 ctx->error_depth = n;
1752 xs = sk_X509_value(ctx->chain, n);
1756 * Do not clear ctx->error=0, it must be "sticky", only the user's callback
1757 * is allowed to reset errors (at its own peril).
1763 * Skip signature check for self signed certificates unless explicitly
1764 * asked for. It doesn't add any security and just wastes time. If
1765 * the issuer's public key is unusable, report the issuer certificate
1766 * and its depth (rather than the depth of the subject).
1768 if (xs != xi || (ctx->param->flags & X509_V_FLAG_CHECK_SS_SIGNATURE)) {
1769 if ((pkey = X509_get0_pubkey(xi)) == NULL) {
1770 if (!verify_cb_cert(ctx, xi, xi != xs ? n+1 : n,
1771 X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY))
1773 } else if (X509_verify_ex(xs, pkey, ctx->libctx, ctx->propq) <= 0) {
1774 if (!verify_cb_cert(ctx, xs, n,
1775 X509_V_ERR_CERT_SIGNATURE_FAILURE))
1781 /* Calls verify callback as needed */
1782 if (!x509_check_cert_time(ctx, xs, n))
1786 * Signal success at this depth. However, the previous error (if any)
1789 ctx->current_issuer = xi;
1790 ctx->current_cert = xs;
1791 ctx->error_depth = n;
1792 if (!ctx->verify_cb(1, ctx))
1797 xs = sk_X509_value(ctx->chain, n);
1803 int X509_cmp_current_time(const ASN1_TIME *ctm)
1805 return X509_cmp_time(ctm, NULL);
1808 int X509_cmp_time(const ASN1_TIME *ctm, time_t *cmp_time)
1810 static const size_t utctime_length = sizeof("YYMMDDHHMMSSZ") - 1;
1811 static const size_t generalizedtime_length = sizeof("YYYYMMDDHHMMSSZ") - 1;
1812 ASN1_TIME *asn1_cmp_time = NULL;
1813 int i, day, sec, ret = 0;
1814 #ifdef CHARSET_EBCDIC
1815 const char upper_z = 0x5A;
1817 const char upper_z = 'Z';
1820 * Note that ASN.1 allows much more slack in the time format than RFC5280.
1821 * In RFC5280, the representation is fixed:
1822 * UTCTime: YYMMDDHHMMSSZ
1823 * GeneralizedTime: YYYYMMDDHHMMSSZ
1825 * We do NOT currently enforce the following RFC 5280 requirement:
1826 * "CAs conforming to this profile MUST always encode certificate
1827 * validity dates through the year 2049 as UTCTime; certificate validity
1828 * dates in 2050 or later MUST be encoded as GeneralizedTime."
1830 switch (ctm->type) {
1831 case V_ASN1_UTCTIME:
1832 if (ctm->length != (int)(utctime_length))
1835 case V_ASN1_GENERALIZEDTIME:
1836 if (ctm->length != (int)(generalizedtime_length))
1844 * Verify the format: the ASN.1 functions we use below allow a more
1845 * flexible format than what's mandated by RFC 5280.
1846 * Digit and date ranges will be verified in the conversion methods.
1848 for (i = 0; i < ctm->length - 1; i++) {
1849 if (!ascii_isdigit(ctm->data[i]))
1852 if (ctm->data[ctm->length - 1] != upper_z)
1856 * There is ASN1_UTCTIME_cmp_time_t but no
1857 * ASN1_GENERALIZEDTIME_cmp_time_t or ASN1_TIME_cmp_time_t,
1858 * so we go through ASN.1
1860 asn1_cmp_time = X509_time_adj(NULL, 0, cmp_time);
1861 if (asn1_cmp_time == NULL)
1863 if (!ASN1_TIME_diff(&day, &sec, ctm, asn1_cmp_time))
1867 * X509_cmp_time comparison is <=.
1868 * The return value 0 is reserved for errors.
1870 ret = (day >= 0 && sec >= 0) ? -1 : 1;
1873 ASN1_TIME_free(asn1_cmp_time);
1878 * Return 0 if time should not be checked or reference time is in range,
1879 * or else 1 if it is past the end, or -1 if it is before the start
1881 int X509_cmp_timeframe(const X509_VERIFY_PARAM *vpm,
1882 const ASN1_TIME *start, const ASN1_TIME *end)
1885 time_t *time = NULL;
1886 unsigned long flags = vpm == NULL ? 0 : X509_VERIFY_PARAM_get_flags(vpm);
1888 if ((flags & X509_V_FLAG_USE_CHECK_TIME) != 0) {
1889 ref_time = X509_VERIFY_PARAM_get_time(vpm);
1891 } else if ((flags & X509_V_FLAG_NO_CHECK_TIME) != 0) {
1892 return 0; /* this means ok */
1893 } /* else reference time is the current time */
1895 if (end != NULL && X509_cmp_time(end, time) < 0)
1897 if (start != NULL && X509_cmp_time(start, time) > 0)
1902 ASN1_TIME *X509_gmtime_adj(ASN1_TIME *s, long adj)
1904 return X509_time_adj(s, adj, NULL);
1907 ASN1_TIME *X509_time_adj(ASN1_TIME *s, long offset_sec, time_t *in_tm)
1909 return X509_time_adj_ex(s, 0, offset_sec, in_tm);
1912 ASN1_TIME *X509_time_adj_ex(ASN1_TIME *s,
1913 int offset_day, long offset_sec, time_t *in_tm)
1922 if (s && !(s->flags & ASN1_STRING_FLAG_MSTRING)) {
1923 if (s->type == V_ASN1_UTCTIME)
1924 return ASN1_UTCTIME_adj(s, t, offset_day, offset_sec);
1925 if (s->type == V_ASN1_GENERALIZEDTIME)
1926 return ASN1_GENERALIZEDTIME_adj(s, t, offset_day, offset_sec);
1928 return ASN1_TIME_adj(s, t, offset_day, offset_sec);
1931 int X509_get_pubkey_parameters(EVP_PKEY *pkey, STACK_OF(X509) *chain)
1933 EVP_PKEY *ktmp = NULL, *ktmp2;
1936 if ((pkey != NULL) && !EVP_PKEY_missing_parameters(pkey))
1939 for (i = 0; i < sk_X509_num(chain); i++) {
1940 ktmp = X509_get0_pubkey(sk_X509_value(chain, i));
1942 X509err(X509_F_X509_GET_PUBKEY_PARAMETERS,
1943 X509_R_UNABLE_TO_GET_CERTS_PUBLIC_KEY);
1946 if (!EVP_PKEY_missing_parameters(ktmp))
1950 X509err(X509_F_X509_GET_PUBKEY_PARAMETERS,
1951 X509_R_UNABLE_TO_FIND_PARAMETERS_IN_CHAIN);
1955 /* first, populate the other certs */
1956 for (j = i - 1; j >= 0; j--) {
1957 ktmp2 = X509_get0_pubkey(sk_X509_value(chain, j));
1958 EVP_PKEY_copy_parameters(ktmp2, ktmp);
1962 EVP_PKEY_copy_parameters(pkey, ktmp);
1966 /* Make a delta CRL as the diff between two full CRLs */
1968 X509_CRL *X509_CRL_diff(X509_CRL *base, X509_CRL *newer,
1969 EVP_PKEY *skey, const EVP_MD *md, unsigned int flags)
1971 X509_CRL *crl = NULL;
1973 STACK_OF(X509_REVOKED) *revs = NULL;
1974 /* CRLs can't be delta already */
1975 if (base->base_crl_number || newer->base_crl_number) {
1976 X509err(X509_F_X509_CRL_DIFF, X509_R_CRL_ALREADY_DELTA);
1979 /* Base and new CRL must have a CRL number */
1980 if (!base->crl_number || !newer->crl_number) {
1981 X509err(X509_F_X509_CRL_DIFF, X509_R_NO_CRL_NUMBER);
1984 /* Issuer names must match */
1985 if (X509_NAME_cmp(X509_CRL_get_issuer(base), X509_CRL_get_issuer(newer))) {
1986 X509err(X509_F_X509_CRL_DIFF, X509_R_ISSUER_MISMATCH);
1989 /* AKID and IDP must match */
1990 if (!crl_extension_match(base, newer, NID_authority_key_identifier)) {
1991 X509err(X509_F_X509_CRL_DIFF, X509_R_AKID_MISMATCH);
1994 if (!crl_extension_match(base, newer, NID_issuing_distribution_point)) {
1995 X509err(X509_F_X509_CRL_DIFF, X509_R_IDP_MISMATCH);
1998 /* Newer CRL number must exceed full CRL number */
1999 if (ASN1_INTEGER_cmp(newer->crl_number, base->crl_number) <= 0) {
2000 X509err(X509_F_X509_CRL_DIFF, X509_R_NEWER_CRL_NOT_NEWER);
2003 /* CRLs must verify */
2004 if (skey && (X509_CRL_verify(base, skey) <= 0 ||
2005 X509_CRL_verify(newer, skey) <= 0)) {
2006 X509err(X509_F_X509_CRL_DIFF, X509_R_CRL_VERIFY_FAILURE);
2009 /* Create new CRL */
2010 crl = X509_CRL_new();
2011 if (crl == NULL || !X509_CRL_set_version(crl, 1))
2013 /* Set issuer name */
2014 if (!X509_CRL_set_issuer_name(crl, X509_CRL_get_issuer(newer)))
2017 if (!X509_CRL_set1_lastUpdate(crl, X509_CRL_get0_lastUpdate(newer)))
2019 if (!X509_CRL_set1_nextUpdate(crl, X509_CRL_get0_nextUpdate(newer)))
2022 /* Set base CRL number: must be critical */
2024 if (!X509_CRL_add1_ext_i2d(crl, NID_delta_crl, base->crl_number, 1, 0))
2028 * Copy extensions across from newest CRL to delta: this will set CRL
2029 * number to correct value too.
2032 for (i = 0; i < X509_CRL_get_ext_count(newer); i++) {
2033 X509_EXTENSION *ext;
2034 ext = X509_CRL_get_ext(newer, i);
2035 if (!X509_CRL_add_ext(crl, ext, -1))
2039 /* Go through revoked entries, copying as needed */
2041 revs = X509_CRL_get_REVOKED(newer);
2043 for (i = 0; i < sk_X509_REVOKED_num(revs); i++) {
2044 X509_REVOKED *rvn, *rvtmp;
2045 rvn = sk_X509_REVOKED_value(revs, i);
2047 * Add only if not also in base. TODO: need something cleverer here
2048 * for some more complex CRLs covering multiple CAs.
2050 if (!X509_CRL_get0_by_serial(base, &rvtmp, &rvn->serialNumber)) {
2051 rvtmp = X509_REVOKED_dup(rvn);
2054 if (!X509_CRL_add0_revoked(crl, rvtmp)) {
2055 X509_REVOKED_free(rvtmp);
2060 /* TODO: optionally prune deleted entries */
2062 if (skey && md && !X509_CRL_sign(crl, skey, md))
2068 X509err(X509_F_X509_CRL_DIFF, ERR_R_MALLOC_FAILURE);
2073 int X509_STORE_CTX_set_ex_data(X509_STORE_CTX *ctx, int idx, void *data)
2075 return CRYPTO_set_ex_data(&ctx->ex_data, idx, data);
2078 void *X509_STORE_CTX_get_ex_data(const X509_STORE_CTX *ctx, int idx)
2080 return CRYPTO_get_ex_data(&ctx->ex_data, idx);
2083 int X509_STORE_CTX_get_error(const X509_STORE_CTX *ctx)
2088 void X509_STORE_CTX_set_error(X509_STORE_CTX *ctx, int err)
2093 int X509_STORE_CTX_get_error_depth(const X509_STORE_CTX *ctx)
2095 return ctx->error_depth;
2098 void X509_STORE_CTX_set_error_depth(X509_STORE_CTX *ctx, int depth)
2100 ctx->error_depth = depth;
2103 X509 *X509_STORE_CTX_get_current_cert(const X509_STORE_CTX *ctx)
2105 return ctx->current_cert;
2108 void X509_STORE_CTX_set_current_cert(X509_STORE_CTX *ctx, X509 *x)
2110 ctx->current_cert = x;
2113 STACK_OF(X509) *X509_STORE_CTX_get0_chain(const X509_STORE_CTX *ctx)
2118 STACK_OF(X509) *X509_STORE_CTX_get1_chain(const X509_STORE_CTX *ctx)
2122 return X509_chain_up_ref(ctx->chain);
2125 X509 *X509_STORE_CTX_get0_current_issuer(const X509_STORE_CTX *ctx)
2127 return ctx->current_issuer;
2130 X509_CRL *X509_STORE_CTX_get0_current_crl(const X509_STORE_CTX *ctx)
2132 return ctx->current_crl;
2135 X509_STORE_CTX *X509_STORE_CTX_get0_parent_ctx(const X509_STORE_CTX *ctx)
2140 void X509_STORE_CTX_set_cert(X509_STORE_CTX *ctx, X509 *x)
2145 void X509_STORE_CTX_set0_crls(X509_STORE_CTX *ctx, STACK_OF(X509_CRL) *sk)
2150 int X509_STORE_CTX_set_purpose(X509_STORE_CTX *ctx, int purpose)
2153 * XXX: Why isn't this function always used to set the associated trust?
2154 * Should there even be a VPM->trust field at all? Or should the trust
2155 * always be inferred from the purpose by X509_STORE_CTX_init().
2157 return X509_STORE_CTX_purpose_inherit(ctx, 0, purpose, 0);
2160 int X509_STORE_CTX_set_trust(X509_STORE_CTX *ctx, int trust)
2163 * XXX: See above, this function would only be needed when the default
2164 * trust for the purpose needs an override in a corner case.
2166 return X509_STORE_CTX_purpose_inherit(ctx, 0, 0, trust);
2170 * This function is used to set the X509_STORE_CTX purpose and trust values.
2171 * This is intended to be used when another structure has its own trust and
2172 * purpose values which (if set) will be inherited by the ctx. If they aren't
2173 * set then we will usually have a default purpose in mind which should then
2174 * be used to set the trust value. An example of this is SSL use: an SSL
2175 * structure will have its own purpose and trust settings which the
2176 * application can set: if they aren't set then we use the default of SSL
2180 int X509_STORE_CTX_purpose_inherit(X509_STORE_CTX *ctx, int def_purpose,
2181 int purpose, int trust)
2184 /* If purpose not set use default */
2186 purpose = def_purpose;
2187 /* If we have a purpose then check it is valid */
2190 idx = X509_PURPOSE_get_by_id(purpose);
2192 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2193 X509_R_UNKNOWN_PURPOSE_ID);
2196 ptmp = X509_PURPOSE_get0(idx);
2197 if (ptmp->trust == X509_TRUST_DEFAULT) {
2198 idx = X509_PURPOSE_get_by_id(def_purpose);
2200 * XXX: In the two callers above def_purpose is always 0, which is
2201 * not a known value, so idx will always be -1. How is the
2202 * X509_TRUST_DEFAULT case actually supposed to be handled?
2205 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2206 X509_R_UNKNOWN_PURPOSE_ID);
2209 ptmp = X509_PURPOSE_get0(idx);
2211 /* If trust not set then get from purpose default */
2213 trust = ptmp->trust;
2216 idx = X509_TRUST_get_by_id(trust);
2218 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2219 X509_R_UNKNOWN_TRUST_ID);
2224 if (purpose && !ctx->param->purpose)
2225 ctx->param->purpose = purpose;
2226 if (trust && !ctx->param->trust)
2227 ctx->param->trust = trust;
2231 X509_STORE_CTX *X509_STORE_CTX_new_with_libctx(OPENSSL_CTX *libctx,
2234 X509_STORE_CTX *ctx = OPENSSL_zalloc(sizeof(*ctx));
2237 X509err(0, ERR_R_MALLOC_FAILURE);
2241 ctx->libctx = libctx;
2242 if (propq != NULL) {
2243 ctx->propq = OPENSSL_strdup(propq);
2244 if (ctx->propq == NULL) {
2246 X509err(0, ERR_R_MALLOC_FAILURE);
2254 X509_STORE_CTX *X509_STORE_CTX_new(void)
2256 return X509_STORE_CTX_new_with_libctx(NULL, NULL);
2260 void X509_STORE_CTX_free(X509_STORE_CTX *ctx)
2265 X509_STORE_CTX_cleanup(ctx);
2267 /* libctx and propq survive X509_STORE_CTX_cleanup() */
2268 OPENSSL_free(ctx->propq);
2273 int X509_STORE_CTX_init(X509_STORE_CTX *ctx, X509_STORE *store, X509 *x509,
2274 STACK_OF(X509) *chain)
2280 ctx->untrusted = chain;
2282 ctx->num_untrusted = 0;
2283 ctx->other_ctx = NULL;
2287 ctx->explicit_policy = 0;
2288 ctx->error_depth = 0;
2289 ctx->current_cert = NULL;
2290 ctx->current_issuer = NULL;
2291 ctx->current_crl = NULL;
2292 ctx->current_crl_score = 0;
2293 ctx->current_reasons = 0;
2297 ctx->bare_ta_signed = 0;
2298 /* Zero ex_data to make sure we're cleanup-safe */
2299 memset(&ctx->ex_data, 0, sizeof(ctx->ex_data));
2301 /* store->cleanup is always 0 in OpenSSL, if set must be idempotent */
2303 ctx->cleanup = store->cleanup;
2307 if (store && store->check_issued)
2308 ctx->check_issued = store->check_issued;
2310 ctx->check_issued = check_issued;
2312 if (store && store->get_issuer)
2313 ctx->get_issuer = store->get_issuer;
2315 ctx->get_issuer = X509_STORE_CTX_get1_issuer;
2317 if (store && store->verify_cb)
2318 ctx->verify_cb = store->verify_cb;
2320 ctx->verify_cb = null_callback;
2322 if (store && store->verify)
2323 ctx->verify = store->verify;
2325 ctx->verify = internal_verify;
2327 if (store && store->check_revocation)
2328 ctx->check_revocation = store->check_revocation;
2330 ctx->check_revocation = check_revocation;
2332 if (store && store->get_crl)
2333 ctx->get_crl = store->get_crl;
2335 ctx->get_crl = NULL;
2337 if (store && store->check_crl)
2338 ctx->check_crl = store->check_crl;
2340 ctx->check_crl = check_crl;
2342 if (store && store->cert_crl)
2343 ctx->cert_crl = store->cert_crl;
2345 ctx->cert_crl = cert_crl;
2347 if (store && store->check_policy)
2348 ctx->check_policy = store->check_policy;
2350 ctx->check_policy = check_policy;
2352 if (store && store->lookup_certs)
2353 ctx->lookup_certs = store->lookup_certs;
2355 ctx->lookup_certs = X509_STORE_CTX_get1_certs;
2357 if (store && store->lookup_crls)
2358 ctx->lookup_crls = store->lookup_crls;
2360 ctx->lookup_crls = X509_STORE_CTX_get1_crls;
2362 ctx->param = X509_VERIFY_PARAM_new();
2363 if (ctx->param == NULL) {
2364 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2369 * Inherit callbacks and flags from X509_STORE if not set use defaults.
2372 ret = X509_VERIFY_PARAM_inherit(ctx->param, store->param);
2374 ctx->param->inh_flags |= X509_VP_FLAG_DEFAULT | X509_VP_FLAG_ONCE;
2377 ret = X509_VERIFY_PARAM_inherit(ctx->param,
2378 X509_VERIFY_PARAM_lookup("default"));
2381 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2386 * XXX: For now, continue to inherit trust from VPM, but infer from the
2387 * purpose if this still yields the default value.
2389 if (ctx->param->trust == X509_TRUST_DEFAULT) {
2390 int idx = X509_PURPOSE_get_by_id(ctx->param->purpose);
2391 X509_PURPOSE *xp = X509_PURPOSE_get0(idx);
2394 ctx->param->trust = X509_PURPOSE_get_trust(xp);
2397 if (CRYPTO_new_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx,
2400 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2404 * On error clean up allocated storage, if the store context was not
2405 * allocated with X509_STORE_CTX_new() this is our last chance to do so.
2407 X509_STORE_CTX_cleanup(ctx);
2412 * Set alternative lookup method: just a STACK of trusted certificates. This
2413 * avoids X509_STORE nastiness where it isn't needed.
2415 void X509_STORE_CTX_set0_trusted_stack(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2417 ctx->other_ctx = sk;
2418 ctx->get_issuer = get_issuer_sk;
2419 ctx->lookup_certs = lookup_certs_sk;
2422 void X509_STORE_CTX_cleanup(X509_STORE_CTX *ctx)
2425 * We need to be idempotent because, unfortunately, free() also calls
2426 * cleanup(), so the natural call sequence new(), init(), cleanup(), free()
2427 * calls cleanup() for the same object twice! Thus we must zero the
2428 * pointers below after they're freed!
2430 /* Seems to always be 0 in OpenSSL, do this at most once. */
2431 if (ctx->cleanup != NULL) {
2433 ctx->cleanup = NULL;
2435 if (ctx->param != NULL) {
2436 if (ctx->parent == NULL)
2437 X509_VERIFY_PARAM_free(ctx->param);
2440 X509_policy_tree_free(ctx->tree);
2442 sk_X509_pop_free(ctx->chain, X509_free);
2444 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx, &(ctx->ex_data));
2445 memset(&ctx->ex_data, 0, sizeof(ctx->ex_data));
2448 void X509_STORE_CTX_set_depth(X509_STORE_CTX *ctx, int depth)
2450 X509_VERIFY_PARAM_set_depth(ctx->param, depth);
2453 void X509_STORE_CTX_set_flags(X509_STORE_CTX *ctx, unsigned long flags)
2455 X509_VERIFY_PARAM_set_flags(ctx->param, flags);
2458 void X509_STORE_CTX_set_time(X509_STORE_CTX *ctx, unsigned long flags,
2461 X509_VERIFY_PARAM_set_time(ctx->param, t);
2464 X509 *X509_STORE_CTX_get0_cert(const X509_STORE_CTX *ctx)
2469 STACK_OF(X509) *X509_STORE_CTX_get0_untrusted(const X509_STORE_CTX *ctx)
2471 return ctx->untrusted;
2474 void X509_STORE_CTX_set0_untrusted(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2476 ctx->untrusted = sk;
2479 void X509_STORE_CTX_set0_verified_chain(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2481 sk_X509_pop_free(ctx->chain, X509_free);
2485 void X509_STORE_CTX_set_verify_cb(X509_STORE_CTX *ctx,
2486 X509_STORE_CTX_verify_cb verify_cb)
2488 ctx->verify_cb = verify_cb;
2491 X509_STORE_CTX_verify_cb X509_STORE_CTX_get_verify_cb(const X509_STORE_CTX *ctx)
2493 return ctx->verify_cb;
2496 void X509_STORE_CTX_set_verify(X509_STORE_CTX *ctx,
2497 X509_STORE_CTX_verify_fn verify)
2499 ctx->verify = verify;
2502 X509_STORE_CTX_verify_fn X509_STORE_CTX_get_verify(const X509_STORE_CTX *ctx)
2507 X509_STORE_CTX_get_issuer_fn X509_STORE_CTX_get_get_issuer(const X509_STORE_CTX *ctx)
2509 return ctx->get_issuer;
2512 X509_STORE_CTX_check_issued_fn
2513 X509_STORE_CTX_get_check_issued(const X509_STORE_CTX *ctx)
2515 return ctx->check_issued;
2518 X509_STORE_CTX_check_revocation_fn
2519 X509_STORE_CTX_get_check_revocation(const X509_STORE_CTX *ctx)
2521 return ctx->check_revocation;
2524 X509_STORE_CTX_get_crl_fn X509_STORE_CTX_get_get_crl(const X509_STORE_CTX *ctx)
2526 return ctx->get_crl;
2529 X509_STORE_CTX_check_crl_fn X509_STORE_CTX_get_check_crl(const X509_STORE_CTX *ctx)
2531 return ctx->check_crl;
2534 X509_STORE_CTX_cert_crl_fn X509_STORE_CTX_get_cert_crl(const X509_STORE_CTX *ctx)
2536 return ctx->cert_crl;
2539 X509_STORE_CTX_check_policy_fn
2540 X509_STORE_CTX_get_check_policy(const X509_STORE_CTX *ctx)
2542 return ctx->check_policy;
2545 X509_STORE_CTX_lookup_certs_fn
2546 X509_STORE_CTX_get_lookup_certs(const X509_STORE_CTX *ctx)
2548 return ctx->lookup_certs;
2551 X509_STORE_CTX_lookup_crls_fn
2552 X509_STORE_CTX_get_lookup_crls(const X509_STORE_CTX *ctx)
2554 return ctx->lookup_crls;
2557 X509_STORE_CTX_cleanup_fn X509_STORE_CTX_get_cleanup(const X509_STORE_CTX *ctx)
2559 return ctx->cleanup;
2562 X509_POLICY_TREE *X509_STORE_CTX_get0_policy_tree(const X509_STORE_CTX *ctx)
2567 int X509_STORE_CTX_get_explicit_policy(const X509_STORE_CTX *ctx)
2569 return ctx->explicit_policy;
2572 int X509_STORE_CTX_get_num_untrusted(const X509_STORE_CTX *ctx)
2574 return ctx->num_untrusted;
2577 int X509_STORE_CTX_set_default(X509_STORE_CTX *ctx, const char *name)
2579 const X509_VERIFY_PARAM *param;
2581 param = X509_VERIFY_PARAM_lookup(name);
2584 return X509_VERIFY_PARAM_inherit(ctx->param, param);
2587 X509_VERIFY_PARAM *X509_STORE_CTX_get0_param(const X509_STORE_CTX *ctx)
2592 void X509_STORE_CTX_set0_param(X509_STORE_CTX *ctx, X509_VERIFY_PARAM *param)
2594 X509_VERIFY_PARAM_free(ctx->param);
2598 void X509_STORE_CTX_set0_dane(X509_STORE_CTX *ctx, SSL_DANE *dane)
2603 static unsigned char *dane_i2d(
2606 unsigned int *i2dlen)
2608 unsigned char *buf = NULL;
2612 * Extract ASN.1 DER form of certificate or public key.
2615 case DANETLS_SELECTOR_CERT:
2616 len = i2d_X509(cert, &buf);
2618 case DANETLS_SELECTOR_SPKI:
2619 len = i2d_X509_PUBKEY(X509_get_X509_PUBKEY(cert), &buf);
2622 X509err(X509_F_DANE_I2D, X509_R_BAD_SELECTOR);
2626 if (len < 0 || buf == NULL) {
2627 X509err(X509_F_DANE_I2D, ERR_R_MALLOC_FAILURE);
2631 *i2dlen = (unsigned int)len;
2635 #define DANETLS_NONE 256 /* impossible uint8_t */
2637 static int dane_match(X509_STORE_CTX *ctx, X509 *cert, int depth)
2639 SSL_DANE *dane = ctx->dane;
2640 unsigned usage = DANETLS_NONE;
2641 unsigned selector = DANETLS_NONE;
2642 unsigned ordinal = DANETLS_NONE;
2643 unsigned mtype = DANETLS_NONE;
2644 unsigned char *i2dbuf = NULL;
2645 unsigned int i2dlen = 0;
2646 unsigned char mdbuf[EVP_MAX_MD_SIZE];
2647 unsigned char *cmpbuf = NULL;
2648 unsigned int cmplen = 0;
2652 danetls_record *t = NULL;
2655 mask = (depth == 0) ? DANETLS_EE_MASK : DANETLS_TA_MASK;
2658 * The trust store is not applicable with DANE-TA(2)
2660 if (depth >= ctx->num_untrusted)
2661 mask &= DANETLS_PKIX_MASK;
2664 * If we've previously matched a PKIX-?? record, no need to test any
2665 * further PKIX-?? records, it remains to just build the PKIX chain.
2666 * Had the match been a DANE-?? record, we'd be done already.
2668 if (dane->mdpth >= 0)
2669 mask &= ~DANETLS_PKIX_MASK;
2672 * https://tools.ietf.org/html/rfc7671#section-5.1
2673 * https://tools.ietf.org/html/rfc7671#section-5.2
2674 * https://tools.ietf.org/html/rfc7671#section-5.3
2675 * https://tools.ietf.org/html/rfc7671#section-5.4
2677 * We handle DANE-EE(3) records first as they require no chain building
2678 * and no expiration or hostname checks. We also process digests with
2679 * higher ordinals first and ignore lower priorities except Full(0) which
2680 * is always processed (last). If none match, we then process PKIX-EE(1).
2682 * NOTE: This relies on DANE usages sorting before the corresponding PKIX
2683 * usages in SSL_dane_tlsa_add(), and also on descending sorting of digest
2684 * priorities. See twin comment in ssl/ssl_lib.c.
2686 * We expect that most TLSA RRsets will have just a single usage, so we
2687 * don't go out of our way to cache multiple selector-specific i2d buffers
2688 * across usages, but if the selector happens to remain the same as switch
2689 * usages, that's OK. Thus, a set of "3 1 1", "3 0 1", "1 1 1", "1 0 1",
2690 * records would result in us generating each of the certificate and public
2691 * key DER forms twice, but more typically we'd just see multiple "3 1 1"
2692 * or multiple "3 0 1" records.
2694 * As soon as we find a match at any given depth, we stop, because either
2695 * we've matched a DANE-?? record and the peer is authenticated, or, after
2696 * exhausting all DANE-?? records, we've matched a PKIX-?? record, which is
2697 * sufficient for DANE, and what remains to do is ordinary PKIX validation.
2699 recnum = (dane->umask & mask) ? sk_danetls_record_num(dane->trecs) : 0;
2700 for (i = 0; matched == 0 && i < recnum; ++i) {
2701 t = sk_danetls_record_value(dane->trecs, i);
2702 if ((DANETLS_USAGE_BIT(t->usage) & mask) == 0)
2704 if (t->usage != usage) {
2707 /* Reset digest agility for each usage/selector pair */
2708 mtype = DANETLS_NONE;
2709 ordinal = dane->dctx->mdord[t->mtype];
2711 if (t->selector != selector) {
2712 selector = t->selector;
2714 /* Update per-selector state */
2715 OPENSSL_free(i2dbuf);
2716 i2dbuf = dane_i2d(cert, selector, &i2dlen);
2720 /* Reset digest agility for each usage/selector pair */
2721 mtype = DANETLS_NONE;
2722 ordinal = dane->dctx->mdord[t->mtype];
2723 } else if (t->mtype != DANETLS_MATCHING_FULL) {
2727 * <https://tools.ietf.org/html/rfc7671#section-9>
2729 * For a fixed selector, after processing all records with the
2730 * highest mtype ordinal, ignore all mtypes with lower ordinals
2731 * other than "Full".
2733 if (dane->dctx->mdord[t->mtype] < ordinal)
2738 * Each time we hit a (new selector or) mtype, re-compute the relevant
2739 * digest, more complex caching is not worth the code space.
2741 if (t->mtype != mtype) {
2742 const EVP_MD *md = dane->dctx->mdevp[mtype = t->mtype];
2748 if (!EVP_Digest(i2dbuf, i2dlen, cmpbuf, &cmplen, md, 0)) {
2756 * Squirrel away the certificate and depth if we have a match. Any
2757 * DANE match is dispositive, but with PKIX we still need to build a
2760 if (cmplen == t->dlen &&
2761 memcmp(cmpbuf, t->data, cmplen) == 0) {
2762 if (DANETLS_USAGE_BIT(usage) & DANETLS_DANE_MASK)
2764 if (matched || dane->mdpth < 0) {
2765 dane->mdpth = depth;
2767 OPENSSL_free(dane->mcert);
2775 /* Clear the one-element DER cache */
2776 OPENSSL_free(i2dbuf);
2780 static int check_dane_issuer(X509_STORE_CTX *ctx, int depth)
2782 SSL_DANE *dane = ctx->dane;
2786 if (!DANETLS_HAS_TA(dane) || depth == 0)
2787 return X509_TRUST_UNTRUSTED;
2790 * Record any DANE trust-anchor matches, for the first depth to test, if
2791 * there's one at that depth. (This'll be false for length 1 chains looking
2792 * for an exact match for the leaf certificate).
2794 cert = sk_X509_value(ctx->chain, depth);
2795 if (cert != NULL && (matched = dane_match(ctx, cert, depth)) < 0)
2796 return X509_TRUST_REJECTED;
2798 ctx->num_untrusted = depth - 1;
2799 return X509_TRUST_TRUSTED;
2802 return X509_TRUST_UNTRUSTED;
2805 static int check_dane_pkeys(X509_STORE_CTX *ctx)
2807 SSL_DANE *dane = ctx->dane;
2809 int num = ctx->num_untrusted;
2810 X509 *cert = sk_X509_value(ctx->chain, num - 1);
2811 int recnum = sk_danetls_record_num(dane->trecs);
2814 for (i = 0; i < recnum; ++i) {
2815 t = sk_danetls_record_value(dane->trecs, i);
2816 if (t->usage != DANETLS_USAGE_DANE_TA ||
2817 t->selector != DANETLS_SELECTOR_SPKI ||
2818 t->mtype != DANETLS_MATCHING_FULL ||
2819 X509_verify_ex(cert, t->spki, ctx->libctx, ctx->propq) <= 0)
2822 /* Clear any PKIX-?? matches that failed to extend to a full chain */
2823 X509_free(dane->mcert);
2826 /* Record match via a bare TA public key */
2827 ctx->bare_ta_signed = 1;
2828 dane->mdpth = num - 1;
2831 /* Prune any excess chain certificates */
2832 num = sk_X509_num(ctx->chain);
2833 for (; num > ctx->num_untrusted; --num)
2834 X509_free(sk_X509_pop(ctx->chain));
2836 return X509_TRUST_TRUSTED;
2839 return X509_TRUST_UNTRUSTED;
2842 static void dane_reset(SSL_DANE *dane)
2845 * Reset state to verify another chain, or clear after failure.
2847 X509_free(dane->mcert);
2854 static int check_leaf_suiteb(X509_STORE_CTX *ctx, X509 *cert)
2856 int err = X509_chain_check_suiteb(NULL, cert, NULL, ctx->param->flags);
2858 if (err == X509_V_OK)
2860 return verify_cb_cert(ctx, cert, 0, err);
2863 static int dane_verify(X509_STORE_CTX *ctx)
2865 X509 *cert = ctx->cert;
2866 SSL_DANE *dane = ctx->dane;
2873 * When testing the leaf certificate, if we match a DANE-EE(3) record,
2874 * dane_match() returns 1 and we're done. If however we match a PKIX-EE(1)
2875 * record, the match depth and matching TLSA record are recorded, but the
2876 * return value is 0, because we still need to find a PKIX trust-anchor.
2877 * Therefore, when DANE authentication is enabled (required), we're done
2879 * + matched < 0, internal error.
2880 * + matched == 1, we matched a DANE-EE(3) record
2881 * + matched == 0, mdepth < 0 (no PKIX-EE match) and there are no
2882 * DANE-TA(2) or PKIX-TA(0) to test.
2884 matched = dane_match(ctx, ctx->cert, 0);
2885 done = matched != 0 || (!DANETLS_HAS_TA(dane) && dane->mdpth < 0);
2888 X509_get_pubkey_parameters(NULL, ctx->chain);
2891 /* Callback invoked as needed */
2892 if (!check_leaf_suiteb(ctx, cert))
2894 /* Callback invoked as needed */
2895 if ((dane->flags & DANE_FLAG_NO_DANE_EE_NAMECHECKS) == 0 &&
2898 /* Bypass internal_verify(), issue depth 0 success callback */
2899 ctx->error_depth = 0;
2900 ctx->current_cert = cert;
2901 return ctx->verify_cb(1, ctx);
2905 ctx->error_depth = 0;
2906 ctx->current_cert = cert;
2907 ctx->error = X509_V_ERR_OUT_OF_MEM;
2912 /* Fail early, TA-based success is not possible */
2913 if (!check_leaf_suiteb(ctx, cert))
2915 return verify_cb_cert(ctx, cert, 0, X509_V_ERR_DANE_NO_MATCH);
2919 * Chain verification for usages 0/1/2. TLSA record matching of depth > 0
2920 * certificates happens in-line with building the rest of the chain.
2922 return verify_chain(ctx);
2925 /* Get issuer, without duplicate suppression */
2926 static int get_issuer(X509 **issuer, X509_STORE_CTX *ctx, X509 *cert)
2928 STACK_OF(X509) *saved_chain = ctx->chain;
2932 ok = ctx->get_issuer(issuer, ctx, cert);
2933 ctx->chain = saved_chain;
2938 static int build_chain(X509_STORE_CTX *ctx)
2940 SSL_DANE *dane = ctx->dane;
2941 int num = sk_X509_num(ctx->chain);
2942 X509 *cert = sk_X509_value(ctx->chain, num - 1);
2944 STACK_OF(X509) *sktmp = NULL;
2945 unsigned int search;
2946 int may_trusted = 0;
2947 int may_alternate = 0;
2948 int trust = X509_TRUST_UNTRUSTED;
2949 int alt_untrusted = 0;
2954 /* Our chain starts with a single untrusted element. */
2955 if (!ossl_assert(num == 1 && ctx->num_untrusted == num)) {
2956 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
2957 ctx->error = X509_V_ERR_UNSPECIFIED;
2961 ss = cert_self_signed(ctx, cert);
2963 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
2964 ctx->error = X509_V_ERR_UNSPECIFIED;
2968 #define S_DOUNTRUSTED (1 << 0) /* Search untrusted chain */
2969 #define S_DOTRUSTED (1 << 1) /* Search trusted store */
2970 #define S_DOALTERNATE (1 << 2) /* Retry with pruned alternate chain */
2972 * Set up search policy, untrusted if possible, trusted-first if enabled.
2973 * If we're doing DANE and not doing PKIX-TA/PKIX-EE, we never look in the
2974 * trust_store, otherwise we might look there first. If not trusted-first,
2975 * and alternate chains are not disabled, try building an alternate chain
2976 * if no luck with untrusted first.
2978 search = (ctx->untrusted != NULL) ? S_DOUNTRUSTED : 0;
2979 if (DANETLS_HAS_PKIX(dane) || !DANETLS_HAS_DANE(dane)) {
2980 if (search == 0 || ctx->param->flags & X509_V_FLAG_TRUSTED_FIRST)
2981 search |= S_DOTRUSTED;
2982 else if (!(ctx->param->flags & X509_V_FLAG_NO_ALT_CHAINS))
2988 * Shallow-copy the stack of untrusted certificates (with TLS, this is
2989 * typically the content of the peer's certificate message) so can make
2990 * multiple passes over it, while free to remove elements as we go.
2992 if (ctx->untrusted && (sktmp = sk_X509_dup(ctx->untrusted)) == NULL) {
2993 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2994 ctx->error = X509_V_ERR_OUT_OF_MEM;
2999 * If we got any "DANE-TA(2) Cert(0) Full(0)" trust-anchors from DNS, add
3000 * them to our working copy of the untrusted certificate stack. Since the
3001 * caller of X509_STORE_CTX_init() may have provided only a leaf cert with
3002 * no corresponding stack of untrusted certificates, we may need to create
3003 * an empty stack first. [ At present only the ssl library provides DANE
3004 * support, and ssl_verify_cert_chain() always provides a non-null stack
3005 * containing at least the leaf certificate, but we must be prepared for
3008 if (DANETLS_ENABLED(dane) && dane->certs != NULL) {
3009 if (sktmp == NULL && (sktmp = sk_X509_new_null()) == NULL) {
3010 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
3011 ctx->error = X509_V_ERR_OUT_OF_MEM;
3014 for (i = 0; i < sk_X509_num(dane->certs); ++i) {
3015 if (!sk_X509_push(sktmp, sk_X509_value(dane->certs, i))) {
3016 sk_X509_free(sktmp);
3017 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
3018 ctx->error = X509_V_ERR_OUT_OF_MEM;
3025 * Still absurdly large, but arithmetically safe, a lower hard upper bound
3026 * might be reasonable.
3028 if (ctx->param->depth > INT_MAX/2)
3029 ctx->param->depth = INT_MAX/2;
3032 * Try to Extend the chain until we reach an ultimately trusted issuer.
3033 * Build chains up to one longer the limit, later fail if we hit the limit,
3034 * with an X509_V_ERR_CERT_CHAIN_TOO_LONG error code.
3036 depth = ctx->param->depth + 1;
3038 while (search != 0) {
3043 * Look in the trust store if enabled for first lookup, or we've run
3044 * out of untrusted issuers and search here is not disabled. When we
3045 * reach the depth limit, we stop extending the chain, if by that point
3046 * we've not found a trust-anchor, any trusted chain would be too long.
3048 * The error reported to the application verify callback is at the
3049 * maximal valid depth with the current certificate equal to the last
3050 * not ultimately-trusted issuer. For example, with verify_depth = 0,
3051 * the callback will report errors at depth=1 when the immediate issuer
3052 * of the leaf certificate is not a trust anchor. No attempt will be
3053 * made to locate an issuer for that certificate, since such a chain
3054 * would be a-priori too long.
3056 if ((search & S_DOTRUSTED) != 0) {
3057 i = num = sk_X509_num(ctx->chain);
3058 if ((search & S_DOALTERNATE) != 0) {
3060 * As high up the chain as we can, look for an alternative
3061 * trusted issuer of an untrusted certificate that currently
3062 * has an untrusted issuer. We use the alt_untrusted variable
3063 * to track how far up the chain we find the first match. It
3064 * is only if and when we find a match, that we prune the chain
3065 * and reset ctx->num_untrusted to the reduced count of
3066 * untrusted certificates. While we're searching for such a
3067 * match (which may never be found), it is neither safe nor
3068 * wise to preemptively modify either the chain or
3069 * ctx->num_untrusted.
3071 * Note, like ctx->num_untrusted, alt_untrusted is a count of
3072 * untrusted certificates, not a "depth".
3076 x = sk_X509_value(ctx->chain, i-1);
3078 ok = (depth < num) ? 0 : get_issuer(&xtmp, ctx, x);
3081 trust = X509_TRUST_REJECTED;
3082 ctx->error = X509_V_ERR_STORE_LOOKUP;
3089 * Alternative trusted issuer for a mid-chain untrusted cert?
3090 * Pop the untrusted cert's successors and retry. We might now
3091 * be able to complete a valid chain via the trust store. Note
3092 * that despite the current trust-store match we might still
3093 * fail complete the chain to a suitable trust-anchor, in which
3094 * case we may prune some more untrusted certificates and try
3095 * again. Thus the S_DOALTERNATE bit may yet be turned on
3096 * again with an even shorter untrusted chain!
3098 * If in the process we threw away our matching PKIX-TA trust
3099 * anchor, reset DANE trust. We might find a suitable trusted
3100 * certificate among the ones from the trust store.
3102 if ((search & S_DOALTERNATE) != 0) {
3103 if (!ossl_assert(num > i && i > 0 && ss == 0)) {
3104 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
3106 trust = X509_TRUST_REJECTED;
3107 ctx->error = X509_V_ERR_UNSPECIFIED;
3111 search &= ~S_DOALTERNATE;
3112 for (; num > i; --num)
3113 X509_free(sk_X509_pop(ctx->chain));
3114 ctx->num_untrusted = num;
3116 if (DANETLS_ENABLED(dane) &&
3117 dane->mdpth >= ctx->num_untrusted) {
3119 X509_free(dane->mcert);
3122 if (DANETLS_ENABLED(dane) &&
3123 dane->pdpth >= ctx->num_untrusted)
3128 * Self-signed untrusted certificates get replaced by their
3129 * trusted matching issuer. Otherwise, grow the chain.
3132 if (!sk_X509_push(ctx->chain, x = xtmp)) {
3134 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
3135 trust = X509_TRUST_REJECTED;
3136 ctx->error = X509_V_ERR_OUT_OF_MEM;
3140 ss = cert_self_signed(ctx, x);
3142 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
3143 ctx->error = X509_V_ERR_UNSPECIFIED;
3146 } else if (num == ctx->num_untrusted) {
3148 * We have a self-signed certificate that has the same
3149 * subject name (and perhaps keyid and/or serial number) as
3150 * a trust-anchor. We must have an exact match to avoid
3151 * possible impersonation via key substitution etc.
3153 if (X509_cmp(x, xtmp) != 0) {
3154 /* Self-signed untrusted mimic. */
3159 ctx->num_untrusted = --num;
3160 (void) sk_X509_set(ctx->chain, num, x = xtmp);
3165 * We've added a new trusted certificate to the chain, recheck
3166 * trust. If not done, and not self-signed look deeper.
3167 * Whether or not we're doing "trusted first", we no longer
3168 * look for untrusted certificates from the peer's chain.
3170 * At this point ctx->num_trusted and num must reflect the
3171 * correct number of untrusted certificates, since the DANE
3172 * logic in check_trust() depends on distinguishing CAs from
3173 * "the wire" from CAs from the trust store. In particular, the
3174 * certificate at depth "num" should be the new trusted
3175 * certificate with ctx->num_untrusted <= num.
3178 if (!ossl_assert(ctx->num_untrusted <= num)) {
3179 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
3180 trust = X509_TRUST_REJECTED;
3181 ctx->error = X509_V_ERR_UNSPECIFIED;
3185 search &= ~S_DOUNTRUSTED;
3186 switch (trust = check_trust(ctx, num)) {
3187 case X509_TRUST_TRUSTED:
3188 case X509_TRUST_REJECTED:
3198 * No dispositive decision, and either self-signed or no match, if
3199 * we were doing untrusted-first, and alt-chains are not disabled,
3200 * do that, by repeatedly losing one untrusted element at a time,
3201 * and trying to extend the shorted chain.
3203 if ((search & S_DOUNTRUSTED) == 0) {
3204 /* Continue search for a trusted issuer of a shorter chain? */
3205 if ((search & S_DOALTERNATE) != 0 && --alt_untrusted > 0)
3207 /* Still no luck and no fallbacks left? */
3208 if (!may_alternate || (search & S_DOALTERNATE) != 0 ||
3209 ctx->num_untrusted < 2)
3211 /* Search for a trusted issuer of a shorter chain */
3212 search |= S_DOALTERNATE;
3213 alt_untrusted = ctx->num_untrusted - 1;
3219 * Extend chain with peer-provided certificates
3221 if ((search & S_DOUNTRUSTED) != 0) {
3222 num = sk_X509_num(ctx->chain);
3223 if (!ossl_assert(num == ctx->num_untrusted)) {
3224 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
3225 trust = X509_TRUST_REJECTED;
3226 ctx->error = X509_V_ERR_UNSPECIFIED;
3230 x = sk_X509_value(ctx->chain, num-1);
3233 * Once we run out of untrusted issuers, we stop looking for more
3234 * and start looking only in the trust store if enabled.
3236 xtmp = (ss || depth < num) ? NULL : find_issuer(ctx, sktmp, x);
3238 search &= ~S_DOUNTRUSTED;
3240 search |= S_DOTRUSTED;
3244 /* Drop this issuer from future consideration */
3245 (void) sk_X509_delete_ptr(sktmp, xtmp);
3247 if (!sk_X509_push(ctx->chain, xtmp)) {
3248 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
3249 trust = X509_TRUST_REJECTED;
3250 ctx->error = X509_V_ERR_OUT_OF_MEM;
3255 X509_up_ref(x = xtmp);
3256 ++ctx->num_untrusted;
3257 ss = cert_self_signed(ctx, xtmp);
3259 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
3260 ctx->error = X509_V_ERR_UNSPECIFIED;
3265 * Check for DANE-TA trust of the topmost untrusted certificate.
3267 switch (trust = check_dane_issuer(ctx, ctx->num_untrusted - 1)) {
3268 case X509_TRUST_TRUSTED:
3269 case X509_TRUST_REJECTED:
3275 sk_X509_free(sktmp);
3278 * Last chance to make a trusted chain, either bare DANE-TA public-key
3279 * signers, or else direct leaf PKIX trust.
3281 num = sk_X509_num(ctx->chain);
3283 if (trust == X509_TRUST_UNTRUSTED && DANETLS_HAS_DANE_TA(dane))
3284 trust = check_dane_pkeys(ctx);
3285 if (trust == X509_TRUST_UNTRUSTED && num == ctx->num_untrusted)
3286 trust = check_trust(ctx, num);
3290 case X509_TRUST_TRUSTED:
3292 case X509_TRUST_REJECTED:
3293 /* Callback already issued */
3295 case X509_TRUST_UNTRUSTED:
3297 num = sk_X509_num(ctx->chain);
3299 return verify_cb_cert(ctx, NULL, num-1,
3300 X509_V_ERR_CERT_CHAIN_TOO_LONG);
3301 if (DANETLS_ENABLED(dane) &&
3302 (!DANETLS_HAS_PKIX(dane) || dane->pdpth >= 0))
3303 return verify_cb_cert(ctx, NULL, num-1, X509_V_ERR_DANE_NO_MATCH);
3304 if (ss && sk_X509_num(ctx->chain) == 1)
3305 return verify_cb_cert(ctx, NULL, num-1,
3306 X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT);
3308 return verify_cb_cert(ctx, NULL, num-1,
3309 X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN);
3310 if (ctx->num_untrusted < num)
3311 return verify_cb_cert(ctx, NULL, num-1,
3312 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT);
3313 return verify_cb_cert(ctx, NULL, num-1,
3314 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY);
3318 static const int minbits_table[] = { 80, 112, 128, 192, 256 };
3319 static const int NUM_AUTH_LEVELS = OSSL_NELEM(minbits_table);
3322 * Check whether the public key of ``cert`` meets the security level of
3325 * Returns 1 on success, 0 otherwise.
3327 static int check_key_level(X509_STORE_CTX *ctx, X509 *cert)
3329 EVP_PKEY *pkey = X509_get0_pubkey(cert);
3330 int level = ctx->param->auth_level;
3333 * At security level zero, return without checking for a supported public
3334 * key type. Some engines support key types not understood outside the
3335 * engine, and we only need to understand the key when enforcing a security
3341 /* Unsupported or malformed keys are not secure */
3345 if (level > NUM_AUTH_LEVELS)
3346 level = NUM_AUTH_LEVELS;
3348 return EVP_PKEY_security_bits(pkey) >= minbits_table[level - 1];
3352 * Check whether the signature digest algorithm of ``cert`` meets the security
3353 * level of ``ctx``. Should not be checked for trust anchors (whether
3354 * self-signed or otherwise).
3356 * Returns 1 on success, 0 otherwise.
3358 static int check_sig_level(X509_STORE_CTX *ctx, X509 *cert)
3361 int level = ctx->param->auth_level;
3365 if (level > NUM_AUTH_LEVELS)
3366 level = NUM_AUTH_LEVELS;
3368 if (!X509_get_signature_info(cert, NULL, NULL, &secbits, NULL))
3371 return secbits >= minbits_table[level - 1];