2 * Copyright 1995-2018 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"
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)
111 * FIXME: x509v3_cache_extensions() needs to detect more failures and not
112 * set EXFLAG_SET when that happens. Especially, if the failures are
113 * parse errors, rather than memory pressure!
115 X509_check_purpose(x, -1, 0);
116 if (x->ex_flags & EXFLAG_SS)
122 /* Given a certificate try and find an exact match in the store */
124 static X509 *lookup_cert_match(X509_STORE_CTX *ctx, X509 *x)
126 STACK_OF(X509) *certs;
129 /* Lookup all certs with matching subject name */
130 certs = ctx->lookup_certs(ctx, X509_get_subject_name(x));
133 /* Look for exact match */
134 for (i = 0; i < sk_X509_num(certs); i++) {
135 xtmp = sk_X509_value(certs, i);
136 if (!X509_cmp(xtmp, x))
139 if (i < sk_X509_num(certs))
143 sk_X509_pop_free(certs, X509_free);
148 * Inform the verify callback of an error.
149 * If B<x> is not NULL it is the error cert, otherwise use the chain cert at
151 * If B<err> is not X509_V_OK, that's the error value, otherwise leave
152 * unchanged (presumably set by the caller).
154 * Returns 0 to abort verification with an error, non-zero to continue.
156 static int verify_cb_cert(X509_STORE_CTX *ctx, X509 *x, int depth, int err)
158 ctx->error_depth = depth;
159 ctx->current_cert = (x != NULL) ? x : sk_X509_value(ctx->chain, depth);
160 if (err != X509_V_OK)
162 return ctx->verify_cb(0, ctx);
166 * Inform the verify callback of an error, CRL-specific variant. Here, the
167 * error depth and certificate are already set, we just specify the error
170 * Returns 0 to abort verification with an error, non-zero to continue.
172 static int verify_cb_crl(X509_STORE_CTX *ctx, int err)
175 return ctx->verify_cb(0, ctx);
178 static int check_auth_level(X509_STORE_CTX *ctx)
181 int num = sk_X509_num(ctx->chain);
183 if (ctx->param->auth_level <= 0)
186 for (i = 0; i < num; ++i) {
187 X509 *cert = sk_X509_value(ctx->chain, i);
190 * We've already checked the security of the leaf key, so here we only
191 * check the security of issuer keys.
193 if (i > 0 && !check_key_level(ctx, cert) &&
194 verify_cb_cert(ctx, cert, i, X509_V_ERR_CA_KEY_TOO_SMALL) == 0)
197 * We also check the signature algorithm security of all certificates
198 * except those of the trust anchor at index num-1.
200 if (i < num - 1 && !check_sig_level(ctx, cert) &&
201 verify_cb_cert(ctx, cert, i, X509_V_ERR_CA_MD_TOO_WEAK) == 0)
207 static int verify_chain(X509_STORE_CTX *ctx)
213 * Before either returning with an error, or continuing with CRL checks,
214 * instantiate chain public key parameters.
216 if ((ok = build_chain(ctx)) == 0 ||
217 (ok = check_chain_extensions(ctx)) == 0 ||
218 (ok = check_auth_level(ctx)) == 0 ||
219 (ok = check_id(ctx)) == 0 || 1)
220 X509_get_pubkey_parameters(NULL, ctx->chain);
221 if (ok == 0 || (ok = ctx->check_revocation(ctx)) == 0)
224 err = X509_chain_check_suiteb(&ctx->error_depth, NULL, ctx->chain,
226 if (err != X509_V_OK) {
227 if ((ok = verify_cb_cert(ctx, NULL, ctx->error_depth, err)) == 0)
231 /* Verify chain signatures and expiration times */
232 ok = (ctx->verify != NULL) ? ctx->verify(ctx) : internal_verify(ctx);
236 if ((ok = check_name_constraints(ctx)) == 0)
239 #ifndef OPENSSL_NO_RFC3779
240 /* RFC 3779 path validation, now that CRL check has been done */
241 if ((ok = X509v3_asid_validate_path(ctx)) == 0)
243 if ((ok = X509v3_addr_validate_path(ctx)) == 0)
247 /* If we get this far evaluate policies */
248 if (ctx->param->flags & X509_V_FLAG_POLICY_CHECK)
249 ok = ctx->check_policy(ctx);
253 int X509_verify_cert(X509_STORE_CTX *ctx)
255 SSL_DANE *dane = ctx->dane;
258 if (ctx->cert == NULL) {
259 X509err(X509_F_X509_VERIFY_CERT, X509_R_NO_CERT_SET_FOR_US_TO_VERIFY);
260 ctx->error = X509_V_ERR_INVALID_CALL;
264 if (ctx->chain != NULL) {
266 * This X509_STORE_CTX has already been used to verify a cert. We
267 * cannot do another one.
269 X509err(X509_F_X509_VERIFY_CERT, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
270 ctx->error = X509_V_ERR_INVALID_CALL;
275 * first we make sure the chain we are going to build is present and that
276 * the first entry is in place
278 if (((ctx->chain = sk_X509_new_null()) == NULL) ||
279 (!sk_X509_push(ctx->chain, ctx->cert))) {
280 X509err(X509_F_X509_VERIFY_CERT, ERR_R_MALLOC_FAILURE);
281 ctx->error = X509_V_ERR_OUT_OF_MEM;
284 X509_up_ref(ctx->cert);
285 ctx->num_untrusted = 1;
287 /* If the peer's public key is too weak, we can stop early. */
288 if (!check_key_level(ctx, ctx->cert) &&
289 !verify_cb_cert(ctx, ctx->cert, 0, X509_V_ERR_EE_KEY_TOO_SMALL))
292 if (DANETLS_ENABLED(dane))
293 ret = dane_verify(ctx);
295 ret = verify_chain(ctx);
298 * Safety-net. If we are returning an error, we must also set ctx->error,
299 * so that the chain is not considered verified should the error be ignored
300 * (e.g. TLS with SSL_VERIFY_NONE).
302 if (ret <= 0 && ctx->error == X509_V_OK)
303 ctx->error = X509_V_ERR_UNSPECIFIED;
308 * Given a STACK_OF(X509) find the issuer of cert (if any)
310 static X509 *find_issuer(X509_STORE_CTX *ctx, STACK_OF(X509) *sk, X509 *x)
313 X509 *issuer, *rv = NULL;
315 for (i = 0; i < sk_X509_num(sk); i++) {
316 issuer = sk_X509_value(sk, i);
317 if (ctx->check_issued(ctx, x, issuer)) {
319 if (x509_check_cert_time(ctx, rv, -1))
326 /* Given a possible certificate and issuer check them */
328 static int check_issued(X509_STORE_CTX *ctx, X509 *x, X509 *issuer)
332 return cert_self_signed(x);
333 ret = X509_check_issued(issuer, x);
334 if (ret == X509_V_OK) {
337 /* Special case: single self signed certificate */
338 if (cert_self_signed(x) && sk_X509_num(ctx->chain) == 1)
340 for (i = 0; i < sk_X509_num(ctx->chain); i++) {
341 ch = sk_X509_value(ctx->chain, i);
342 if (ch == issuer || !X509_cmp(ch, issuer)) {
343 ret = X509_V_ERR_PATH_LOOP;
349 return (ret == X509_V_OK);
352 /* Alternative lookup method: look from a STACK stored in other_ctx */
354 static int get_issuer_sk(X509 **issuer, X509_STORE_CTX *ctx, X509 *x)
356 *issuer = find_issuer(ctx, ctx->other_ctx, x);
358 X509_up_ref(*issuer);
364 static STACK_OF(X509) *lookup_certs_sk(X509_STORE_CTX *ctx, X509_NAME *nm)
366 STACK_OF(X509) *sk = NULL;
370 for (i = 0; i < sk_X509_num(ctx->other_ctx); i++) {
371 x = sk_X509_value(ctx->other_ctx, i);
372 if (X509_NAME_cmp(nm, X509_get_subject_name(x)) == 0) {
374 sk = sk_X509_new_null();
375 if (sk == NULL || sk_X509_push(sk, x) == 0) {
376 sk_X509_pop_free(sk, X509_free);
377 X509err(X509_F_LOOKUP_CERTS_SK, ERR_R_MALLOC_FAILURE);
378 ctx->error = X509_V_ERR_OUT_OF_MEM;
388 * Check EE or CA certificate purpose. For trusted certificates explicit local
389 * auxiliary trust can be used to override EKU-restrictions.
391 static int check_purpose(X509_STORE_CTX *ctx, X509 *x, int purpose, int depth,
394 int tr_ok = X509_TRUST_UNTRUSTED;
397 * For trusted certificates we want to see whether any auxiliary trust
398 * settings trump the purpose constraints.
400 * This is complicated by the fact that the trust ordinals in
401 * ctx->param->trust are entirely independent of the purpose ordinals in
402 * ctx->param->purpose!
404 * What connects them is their mutual initialization via calls from
405 * X509_STORE_CTX_set_default() into X509_VERIFY_PARAM_lookup() which sets
406 * related values of both param->trust and param->purpose. It is however
407 * typically possible to infer associated trust values from a purpose value
408 * via the X509_PURPOSE API.
410 * Therefore, we can only check for trust overrides when the purpose we're
411 * checking is the same as ctx->param->purpose and ctx->param->trust is
414 if (depth >= ctx->num_untrusted && purpose == ctx->param->purpose)
415 tr_ok = X509_check_trust(x, ctx->param->trust, X509_TRUST_NO_SS_COMPAT);
418 case X509_TRUST_TRUSTED:
420 case X509_TRUST_REJECTED:
423 switch (X509_check_purpose(x, purpose, must_be_ca > 0)) {
429 if ((ctx->param->flags & X509_V_FLAG_X509_STRICT) == 0)
435 return verify_cb_cert(ctx, x, depth, X509_V_ERR_INVALID_PURPOSE);
439 * Check a certificate chains extensions for consistency with the supplied
443 static int check_chain_extensions(X509_STORE_CTX *ctx)
445 int i, must_be_ca, plen = 0;
447 int proxy_path_length = 0;
449 int allow_proxy_certs;
450 int num = sk_X509_num(ctx->chain);
453 * must_be_ca can have 1 of 3 values:
454 * -1: we accept both CA and non-CA certificates, to allow direct
455 * use of self-signed certificates (which are marked as CA).
456 * 0: we only accept non-CA certificates. This is currently not
457 * used, but the possibility is present for future extensions.
458 * 1: we only accept CA certificates. This is currently used for
459 * all certificates in the chain except the leaf certificate.
463 /* CRL path validation */
465 allow_proxy_certs = 0;
466 purpose = X509_PURPOSE_CRL_SIGN;
469 ! !(ctx->param->flags & X509_V_FLAG_ALLOW_PROXY_CERTS);
470 purpose = ctx->param->purpose;
473 for (i = 0; i < num; i++) {
475 x = sk_X509_value(ctx->chain, i);
476 if (!(ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL)
477 && (x->ex_flags & EXFLAG_CRITICAL)) {
478 if (!verify_cb_cert(ctx, x, i,
479 X509_V_ERR_UNHANDLED_CRITICAL_EXTENSION))
482 if (!allow_proxy_certs && (x->ex_flags & EXFLAG_PROXY)) {
483 if (!verify_cb_cert(ctx, x, i,
484 X509_V_ERR_PROXY_CERTIFICATES_NOT_ALLOWED))
487 ret = X509_check_ca(x);
488 switch (must_be_ca) {
490 if ((ctx->param->flags & X509_V_FLAG_X509_STRICT)
491 && (ret != 1) && (ret != 0)) {
493 ctx->error = X509_V_ERR_INVALID_CA;
500 ctx->error = X509_V_ERR_INVALID_NON_CA;
505 /* X509_V_FLAG_X509_STRICT is implicit for intermediate CAs */
507 || ((i + 1 < num || ctx->param->flags & X509_V_FLAG_X509_STRICT)
510 ctx->error = X509_V_ERR_INVALID_CA;
515 if (ret == 0 && !verify_cb_cert(ctx, x, i, X509_V_OK))
517 /* check_purpose() makes the callback as needed */
518 if (purpose > 0 && !check_purpose(ctx, x, purpose, i, must_be_ca))
521 if ((i > 1) && (x->ex_pathlen != -1)
522 && (plen > (x->ex_pathlen + proxy_path_length))) {
523 if (!verify_cb_cert(ctx, x, i, X509_V_ERR_PATH_LENGTH_EXCEEDED))
526 /* Increment path length if not a self issued intermediate CA */
527 if (i > 0 && (x->ex_flags & EXFLAG_SI) == 0)
530 * If this certificate is a proxy certificate, the next certificate
531 * must be another proxy certificate or a EE certificate. If not,
532 * the next certificate must be a CA certificate.
534 if (x->ex_flags & EXFLAG_PROXY) {
536 * RFC3820, 4.1.3 (b)(1) stipulates that if pCPathLengthConstraint
537 * is less than max_path_length, the former should be copied to
538 * the latter, and 4.1.4 (a) stipulates that max_path_length
539 * should be verified to be larger than zero and decrement it.
541 * Because we're checking the certs in the reverse order, we start
542 * with verifying that proxy_path_length isn't larger than pcPLC,
543 * and copy the latter to the former if it is, and finally,
544 * increment proxy_path_length.
546 if (x->ex_pcpathlen != -1) {
547 if (proxy_path_length > x->ex_pcpathlen) {
548 if (!verify_cb_cert(ctx, x, i,
549 X509_V_ERR_PROXY_PATH_LENGTH_EXCEEDED))
552 proxy_path_length = x->ex_pcpathlen;
562 static int has_san_id(X509 *x, int gtype)
566 GENERAL_NAMES *gs = X509_get_ext_d2i(x, NID_subject_alt_name, NULL, NULL);
571 for (i = 0; i < sk_GENERAL_NAME_num(gs); i++) {
572 GENERAL_NAME *g = sk_GENERAL_NAME_value(gs, i);
574 if (g->type == gtype) {
579 GENERAL_NAMES_free(gs);
583 static int check_name_constraints(X509_STORE_CTX *ctx)
587 /* Check name constraints for all certificates */
588 for (i = sk_X509_num(ctx->chain) - 1; i >= 0; i--) {
589 X509 *x = sk_X509_value(ctx->chain, i);
592 /* Ignore self issued certs unless last in chain */
593 if (i && (x->ex_flags & EXFLAG_SI))
597 * Proxy certificates policy has an extra constraint, where the
598 * certificate subject MUST be the issuer with a single CN entry
600 * (RFC 3820: 3.4, 4.1.3 (a)(4))
602 if (x->ex_flags & EXFLAG_PROXY) {
603 X509_NAME *tmpsubject = X509_get_subject_name(x);
604 X509_NAME *tmpissuer = X509_get_issuer_name(x);
605 X509_NAME_ENTRY *tmpentry = NULL;
606 int last_object_nid = 0;
608 int last_object_loc = X509_NAME_entry_count(tmpsubject) - 1;
610 /* Check that there are at least two RDNs */
611 if (last_object_loc < 1) {
612 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
613 goto proxy_name_done;
617 * Check that there is exactly one more RDN in subject as
618 * there is in issuer.
620 if (X509_NAME_entry_count(tmpsubject)
621 != X509_NAME_entry_count(tmpissuer) + 1) {
622 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
623 goto proxy_name_done;
627 * Check that the last subject component isn't part of a
630 if (X509_NAME_ENTRY_set(X509_NAME_get_entry(tmpsubject,
632 == X509_NAME_ENTRY_set(X509_NAME_get_entry(tmpsubject,
633 last_object_loc - 1))) {
634 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
635 goto proxy_name_done;
639 * Check that the last subject RDN is a commonName, and that
640 * all the previous RDNs match the issuer exactly
642 tmpsubject = X509_NAME_dup(tmpsubject);
643 if (tmpsubject == NULL) {
644 X509err(X509_F_CHECK_NAME_CONSTRAINTS, ERR_R_MALLOC_FAILURE);
645 ctx->error = X509_V_ERR_OUT_OF_MEM;
650 X509_NAME_delete_entry(tmpsubject, last_object_loc);
652 OBJ_obj2nid(X509_NAME_ENTRY_get_object(tmpentry));
654 if (last_object_nid != NID_commonName
655 || X509_NAME_cmp(tmpsubject, tmpissuer) != 0) {
656 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
659 X509_NAME_ENTRY_free(tmpentry);
660 X509_NAME_free(tmpsubject);
664 && !verify_cb_cert(ctx, x, i, err))
669 * Check against constraints for all certificates higher in chain
670 * including trust anchor. Trust anchor not strictly speaking needed
671 * but if it includes constraints it is to be assumed it expects them
674 for (j = sk_X509_num(ctx->chain) - 1; j > i; j--) {
675 NAME_CONSTRAINTS *nc = sk_X509_value(ctx->chain, j)->nc;
678 int rv = NAME_CONSTRAINTS_check(x, nc);
680 /* If EE certificate check commonName too */
681 if (rv == X509_V_OK && i == 0
682 && (ctx->param->hostflags
683 & X509_CHECK_FLAG_NEVER_CHECK_SUBJECT) == 0
684 && ((ctx->param->hostflags
685 & X509_CHECK_FLAG_ALWAYS_CHECK_SUBJECT) != 0
686 || !has_san_id(x, GEN_DNS)))
687 rv = NAME_CONSTRAINTS_check_CN(x, nc);
692 case X509_V_ERR_OUT_OF_MEM:
695 if (!verify_cb_cert(ctx, x, i, rv))
705 static int check_id_error(X509_STORE_CTX *ctx, int errcode)
707 return verify_cb_cert(ctx, ctx->cert, 0, errcode);
710 static int check_hosts(X509 *x, X509_VERIFY_PARAM *vpm)
713 int n = sk_OPENSSL_STRING_num(vpm->hosts);
716 if (vpm->peername != NULL) {
717 OPENSSL_free(vpm->peername);
718 vpm->peername = NULL;
720 for (i = 0; i < n; ++i) {
721 name = sk_OPENSSL_STRING_value(vpm->hosts, i);
722 if (X509_check_host(x, name, 0, vpm->hostflags, &vpm->peername) > 0)
728 static int check_id(X509_STORE_CTX *ctx)
730 X509_VERIFY_PARAM *vpm = ctx->param;
732 if (vpm->hosts && check_hosts(x, vpm) <= 0) {
733 if (!check_id_error(ctx, X509_V_ERR_HOSTNAME_MISMATCH))
736 if (vpm->email && X509_check_email(x, vpm->email, vpm->emaillen, 0) <= 0) {
737 if (!check_id_error(ctx, X509_V_ERR_EMAIL_MISMATCH))
740 if (vpm->ip && X509_check_ip(x, vpm->ip, vpm->iplen, 0) <= 0) {
741 if (!check_id_error(ctx, X509_V_ERR_IP_ADDRESS_MISMATCH))
747 static int check_trust(X509_STORE_CTX *ctx, int num_untrusted)
752 SSL_DANE *dane = ctx->dane;
753 int num = sk_X509_num(ctx->chain);
757 * Check for a DANE issuer at depth 1 or greater, if it is a DANE-TA(2)
758 * match, we're done, otherwise we'll merely record the match depth.
760 if (DANETLS_HAS_TA(dane) && num_untrusted > 0 && num_untrusted < num) {
761 switch (trust = check_dane_issuer(ctx, num_untrusted)) {
762 case X509_TRUST_TRUSTED:
763 case X509_TRUST_REJECTED:
769 * Check trusted certificates in chain at depth num_untrusted and up.
770 * Note, that depths 0..num_untrusted-1 may also contain trusted
771 * certificates, but the caller is expected to have already checked those,
772 * and wants to incrementally check just any added since.
774 for (i = num_untrusted; i < num; i++) {
775 x = sk_X509_value(ctx->chain, i);
776 trust = X509_check_trust(x, ctx->param->trust, 0);
777 /* If explicitly trusted return trusted */
778 if (trust == X509_TRUST_TRUSTED)
780 if (trust == X509_TRUST_REJECTED)
785 * If we are looking at a trusted certificate, and accept partial chains,
786 * the chain is PKIX trusted.
788 if (num_untrusted < num) {
789 if (ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN)
791 return X509_TRUST_UNTRUSTED;
794 if (num_untrusted == num && ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) {
796 * Last-resort call with no new trusted certificates, check the leaf
797 * for a direct trust store match.
800 x = sk_X509_value(ctx->chain, i);
801 mx = lookup_cert_match(ctx, x);
803 return X509_TRUST_UNTRUSTED;
806 * Check explicit auxiliary trust/reject settings. If none are set,
807 * we'll accept X509_TRUST_UNTRUSTED when not self-signed.
809 trust = X509_check_trust(mx, ctx->param->trust, 0);
810 if (trust == X509_TRUST_REJECTED) {
815 /* Replace leaf with trusted match */
816 (void) sk_X509_set(ctx->chain, 0, mx);
818 ctx->num_untrusted = 0;
823 * If no trusted certs in chain at all return untrusted and allow
824 * standard (no issuer cert) etc errors to be indicated.
826 return X509_TRUST_UNTRUSTED;
829 if (!verify_cb_cert(ctx, x, i, X509_V_ERR_CERT_REJECTED))
830 return X509_TRUST_REJECTED;
831 return X509_TRUST_UNTRUSTED;
834 if (!DANETLS_ENABLED(dane))
835 return X509_TRUST_TRUSTED;
837 dane->pdpth = num_untrusted;
838 /* With DANE, PKIX alone is not trusted until we have both */
839 if (dane->mdpth >= 0)
840 return X509_TRUST_TRUSTED;
841 return X509_TRUST_UNTRUSTED;
844 static int check_revocation(X509_STORE_CTX *ctx)
846 int i = 0, last = 0, ok = 0;
847 if (!(ctx->param->flags & X509_V_FLAG_CRL_CHECK))
849 if (ctx->param->flags & X509_V_FLAG_CRL_CHECK_ALL)
850 last = sk_X509_num(ctx->chain) - 1;
852 /* If checking CRL paths this isn't the EE certificate */
857 for (i = 0; i <= last; i++) {
858 ctx->error_depth = i;
859 ok = check_cert(ctx);
866 static int check_cert(X509_STORE_CTX *ctx)
868 X509_CRL *crl = NULL, *dcrl = NULL;
870 int cnum = ctx->error_depth;
871 X509 *x = sk_X509_value(ctx->chain, cnum);
873 ctx->current_cert = x;
874 ctx->current_issuer = NULL;
875 ctx->current_crl_score = 0;
876 ctx->current_reasons = 0;
878 if (x->ex_flags & EXFLAG_PROXY)
881 while (ctx->current_reasons != CRLDP_ALL_REASONS) {
882 unsigned int last_reasons = ctx->current_reasons;
884 /* Try to retrieve relevant CRL */
886 ok = ctx->get_crl(ctx, &crl, x);
888 ok = get_crl_delta(ctx, &crl, &dcrl, x);
890 * If error looking up CRL, nothing we can do except notify callback
893 ok = verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL);
896 ctx->current_crl = crl;
897 ok = ctx->check_crl(ctx, crl);
902 ok = ctx->check_crl(ctx, dcrl);
905 ok = ctx->cert_crl(ctx, dcrl, x);
911 /* Don't look in full CRL if delta reason is removefromCRL */
913 ok = ctx->cert_crl(ctx, crl, x);
923 * If reasons not updated we won't get anywhere by another iteration,
926 if (last_reasons == ctx->current_reasons) {
927 ok = verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL);
935 ctx->current_crl = NULL;
939 /* Check CRL times against values in X509_STORE_CTX */
941 static int check_crl_time(X509_STORE_CTX *ctx, X509_CRL *crl, int notify)
947 ctx->current_crl = crl;
948 if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME)
949 ptime = &ctx->param->check_time;
950 else if (ctx->param->flags & X509_V_FLAG_NO_CHECK_TIME)
955 i = X509_cmp_time(X509_CRL_get0_lastUpdate(crl), ptime);
959 if (!verify_cb_crl(ctx, X509_V_ERR_ERROR_IN_CRL_LAST_UPDATE_FIELD))
966 if (!verify_cb_crl(ctx, X509_V_ERR_CRL_NOT_YET_VALID))
970 if (X509_CRL_get0_nextUpdate(crl)) {
971 i = X509_cmp_time(X509_CRL_get0_nextUpdate(crl), ptime);
976 if (!verify_cb_crl(ctx, X509_V_ERR_ERROR_IN_CRL_NEXT_UPDATE_FIELD))
979 /* Ignore expiry of base CRL is delta is valid */
980 if ((i < 0) && !(ctx->current_crl_score & CRL_SCORE_TIME_DELTA)) {
983 if (!verify_cb_crl(ctx, X509_V_ERR_CRL_HAS_EXPIRED))
989 ctx->current_crl = NULL;
994 static int get_crl_sk(X509_STORE_CTX *ctx, X509_CRL **pcrl, X509_CRL **pdcrl,
995 X509 **pissuer, int *pscore, unsigned int *preasons,
996 STACK_OF(X509_CRL) *crls)
998 int i, crl_score, best_score = *pscore;
999 unsigned int reasons, best_reasons = 0;
1000 X509 *x = ctx->current_cert;
1001 X509_CRL *crl, *best_crl = NULL;
1002 X509 *crl_issuer = NULL, *best_crl_issuer = NULL;
1004 for (i = 0; i < sk_X509_CRL_num(crls); i++) {
1005 crl = sk_X509_CRL_value(crls, i);
1006 reasons = *preasons;
1007 crl_score = get_crl_score(ctx, &crl_issuer, &reasons, crl, x);
1008 if (crl_score < best_score || crl_score == 0)
1010 /* If current CRL is equivalent use it if it is newer */
1011 if (crl_score == best_score && best_crl != NULL) {
1013 if (ASN1_TIME_diff(&day, &sec, X509_CRL_get0_lastUpdate(best_crl),
1014 X509_CRL_get0_lastUpdate(crl)) == 0)
1017 * ASN1_TIME_diff never returns inconsistent signs for |day|
1020 if (day <= 0 && sec <= 0)
1024 best_crl_issuer = crl_issuer;
1025 best_score = crl_score;
1026 best_reasons = reasons;
1030 X509_CRL_free(*pcrl);
1032 *pissuer = best_crl_issuer;
1033 *pscore = best_score;
1034 *preasons = best_reasons;
1035 X509_CRL_up_ref(best_crl);
1036 X509_CRL_free(*pdcrl);
1038 get_delta_sk(ctx, pdcrl, pscore, best_crl, crls);
1041 if (best_score >= CRL_SCORE_VALID)
1048 * Compare two CRL extensions for delta checking purposes. They should be
1049 * both present or both absent. If both present all fields must be identical.
1052 static int crl_extension_match(X509_CRL *a, X509_CRL *b, int nid)
1054 ASN1_OCTET_STRING *exta, *extb;
1056 i = X509_CRL_get_ext_by_NID(a, nid, -1);
1058 /* Can't have multiple occurrences */
1059 if (X509_CRL_get_ext_by_NID(a, nid, i) != -1)
1061 exta = X509_EXTENSION_get_data(X509_CRL_get_ext(a, i));
1065 i = X509_CRL_get_ext_by_NID(b, nid, -1);
1069 if (X509_CRL_get_ext_by_NID(b, nid, i) != -1)
1071 extb = X509_EXTENSION_get_data(X509_CRL_get_ext(b, i));
1081 if (ASN1_OCTET_STRING_cmp(exta, extb))
1087 /* See if a base and delta are compatible */
1089 static int check_delta_base(X509_CRL *delta, X509_CRL *base)
1091 /* Delta CRL must be a delta */
1092 if (!delta->base_crl_number)
1094 /* Base must have a CRL number */
1095 if (!base->crl_number)
1097 /* Issuer names must match */
1098 if (X509_NAME_cmp(X509_CRL_get_issuer(base), X509_CRL_get_issuer(delta)))
1100 /* AKID and IDP must match */
1101 if (!crl_extension_match(delta, base, NID_authority_key_identifier))
1103 if (!crl_extension_match(delta, base, NID_issuing_distribution_point))
1105 /* Delta CRL base number must not exceed Full CRL number. */
1106 if (ASN1_INTEGER_cmp(delta->base_crl_number, base->crl_number) > 0)
1108 /* Delta CRL number must exceed full CRL number */
1109 if (ASN1_INTEGER_cmp(delta->crl_number, base->crl_number) > 0)
1115 * For a given base CRL find a delta... maybe extend to delta scoring or
1116 * retrieve a chain of deltas...
1119 static void get_delta_sk(X509_STORE_CTX *ctx, X509_CRL **dcrl, int *pscore,
1120 X509_CRL *base, STACK_OF(X509_CRL) *crls)
1124 if (!(ctx->param->flags & X509_V_FLAG_USE_DELTAS))
1126 if (!((ctx->current_cert->ex_flags | base->flags) & EXFLAG_FRESHEST))
1128 for (i = 0; i < sk_X509_CRL_num(crls); i++) {
1129 delta = sk_X509_CRL_value(crls, i);
1130 if (check_delta_base(delta, base)) {
1131 if (check_crl_time(ctx, delta, 0))
1132 *pscore |= CRL_SCORE_TIME_DELTA;
1133 X509_CRL_up_ref(delta);
1142 * For a given CRL return how suitable it is for the supplied certificate
1143 * 'x'. The return value is a mask of several criteria. If the issuer is not
1144 * the certificate issuer this is returned in *pissuer. The reasons mask is
1145 * also used to determine if the CRL is suitable: if no new reasons the CRL
1146 * is rejected, otherwise reasons is updated.
1149 static int get_crl_score(X509_STORE_CTX *ctx, X509 **pissuer,
1150 unsigned int *preasons, X509_CRL *crl, X509 *x)
1154 unsigned int tmp_reasons = *preasons, crl_reasons;
1156 /* First see if we can reject CRL straight away */
1158 /* Invalid IDP cannot be processed */
1159 if (crl->idp_flags & IDP_INVALID)
1161 /* Reason codes or indirect CRLs need extended CRL support */
1162 if (!(ctx->param->flags & X509_V_FLAG_EXTENDED_CRL_SUPPORT)) {
1163 if (crl->idp_flags & (IDP_INDIRECT | IDP_REASONS))
1165 } else if (crl->idp_flags & IDP_REASONS) {
1166 /* If no new reasons reject */
1167 if (!(crl->idp_reasons & ~tmp_reasons))
1170 /* Don't process deltas at this stage */
1171 else if (crl->base_crl_number)
1173 /* If issuer name doesn't match certificate need indirect CRL */
1174 if (X509_NAME_cmp(X509_get_issuer_name(x), X509_CRL_get_issuer(crl))) {
1175 if (!(crl->idp_flags & IDP_INDIRECT))
1178 crl_score |= CRL_SCORE_ISSUER_NAME;
1180 if (!(crl->flags & EXFLAG_CRITICAL))
1181 crl_score |= CRL_SCORE_NOCRITICAL;
1184 if (check_crl_time(ctx, crl, 0))
1185 crl_score |= CRL_SCORE_TIME;
1187 /* Check authority key ID and locate certificate issuer */
1188 crl_akid_check(ctx, crl, pissuer, &crl_score);
1190 /* If we can't locate certificate issuer at this point forget it */
1192 if (!(crl_score & CRL_SCORE_AKID))
1195 /* Check cert for matching CRL distribution points */
1197 if (crl_crldp_check(x, crl, crl_score, &crl_reasons)) {
1198 /* If no new reasons reject */
1199 if (!(crl_reasons & ~tmp_reasons))
1201 tmp_reasons |= crl_reasons;
1202 crl_score |= CRL_SCORE_SCOPE;
1205 *preasons = tmp_reasons;
1211 static void crl_akid_check(X509_STORE_CTX *ctx, X509_CRL *crl,
1212 X509 **pissuer, int *pcrl_score)
1214 X509 *crl_issuer = NULL;
1215 X509_NAME *cnm = X509_CRL_get_issuer(crl);
1216 int cidx = ctx->error_depth;
1219 if (cidx != sk_X509_num(ctx->chain) - 1)
1222 crl_issuer = sk_X509_value(ctx->chain, cidx);
1224 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1225 if (*pcrl_score & CRL_SCORE_ISSUER_NAME) {
1226 *pcrl_score |= CRL_SCORE_AKID | CRL_SCORE_ISSUER_CERT;
1227 *pissuer = crl_issuer;
1232 for (cidx++; cidx < sk_X509_num(ctx->chain); cidx++) {
1233 crl_issuer = sk_X509_value(ctx->chain, cidx);
1234 if (X509_NAME_cmp(X509_get_subject_name(crl_issuer), cnm))
1236 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1237 *pcrl_score |= CRL_SCORE_AKID | CRL_SCORE_SAME_PATH;
1238 *pissuer = crl_issuer;
1243 /* Anything else needs extended CRL support */
1245 if (!(ctx->param->flags & X509_V_FLAG_EXTENDED_CRL_SUPPORT))
1249 * Otherwise the CRL issuer is not on the path. Look for it in the set of
1250 * untrusted certificates.
1252 for (i = 0; i < sk_X509_num(ctx->untrusted); i++) {
1253 crl_issuer = sk_X509_value(ctx->untrusted, i);
1254 if (X509_NAME_cmp(X509_get_subject_name(crl_issuer), cnm))
1256 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1257 *pissuer = crl_issuer;
1258 *pcrl_score |= CRL_SCORE_AKID;
1265 * Check the path of a CRL issuer certificate. This creates a new
1266 * X509_STORE_CTX and populates it with most of the parameters from the
1267 * parent. This could be optimised somewhat since a lot of path checking will
1268 * be duplicated by the parent, but this will rarely be used in practice.
1271 static int check_crl_path(X509_STORE_CTX *ctx, X509 *x)
1273 X509_STORE_CTX crl_ctx;
1276 /* Don't allow recursive CRL path validation */
1279 if (!X509_STORE_CTX_init(&crl_ctx, ctx->store, x, ctx->untrusted))
1282 crl_ctx.crls = ctx->crls;
1283 /* Copy verify params across */
1284 X509_STORE_CTX_set0_param(&crl_ctx, ctx->param);
1286 crl_ctx.parent = ctx;
1287 crl_ctx.verify_cb = ctx->verify_cb;
1289 /* Verify CRL issuer */
1290 ret = X509_verify_cert(&crl_ctx);
1294 /* Check chain is acceptable */
1295 ret = check_crl_chain(ctx, ctx->chain, crl_ctx.chain);
1297 X509_STORE_CTX_cleanup(&crl_ctx);
1302 * RFC3280 says nothing about the relationship between CRL path and
1303 * certificate path, which could lead to situations where a certificate could
1304 * be revoked or validated by a CA not authorised to do so. RFC5280 is more
1305 * strict and states that the two paths must end in the same trust anchor,
1306 * though some discussions remain... until this is resolved we use the
1310 static int check_crl_chain(X509_STORE_CTX *ctx,
1311 STACK_OF(X509) *cert_path,
1312 STACK_OF(X509) *crl_path)
1314 X509 *cert_ta, *crl_ta;
1315 cert_ta = sk_X509_value(cert_path, sk_X509_num(cert_path) - 1);
1316 crl_ta = sk_X509_value(crl_path, sk_X509_num(crl_path) - 1);
1317 if (!X509_cmp(cert_ta, crl_ta))
1323 * Check for match between two dist point names: three separate cases.
1324 * 1. Both are relative names and compare X509_NAME types.
1325 * 2. One full, one relative. Compare X509_NAME to GENERAL_NAMES.
1326 * 3. Both are full names and compare two GENERAL_NAMES.
1327 * 4. One is NULL: automatic match.
1330 static int idp_check_dp(DIST_POINT_NAME *a, DIST_POINT_NAME *b)
1332 X509_NAME *nm = NULL;
1333 GENERAL_NAMES *gens = NULL;
1334 GENERAL_NAME *gena, *genb;
1341 /* Case 1: two X509_NAME */
1345 if (!X509_NAME_cmp(a->dpname, b->dpname))
1350 /* Case 2: set name and GENERAL_NAMES appropriately */
1352 gens = b->name.fullname;
1353 } else if (b->type == 1) {
1356 /* Case 2: set name and GENERAL_NAMES appropriately */
1357 gens = a->name.fullname;
1361 /* Handle case 2 with one GENERAL_NAMES and one X509_NAME */
1363 for (i = 0; i < sk_GENERAL_NAME_num(gens); i++) {
1364 gena = sk_GENERAL_NAME_value(gens, i);
1365 if (gena->type != GEN_DIRNAME)
1367 if (!X509_NAME_cmp(nm, gena->d.directoryName))
1373 /* Else case 3: two GENERAL_NAMES */
1375 for (i = 0; i < sk_GENERAL_NAME_num(a->name.fullname); i++) {
1376 gena = sk_GENERAL_NAME_value(a->name.fullname, i);
1377 for (j = 0; j < sk_GENERAL_NAME_num(b->name.fullname); j++) {
1378 genb = sk_GENERAL_NAME_value(b->name.fullname, j);
1379 if (!GENERAL_NAME_cmp(gena, genb))
1388 static int crldp_check_crlissuer(DIST_POINT *dp, X509_CRL *crl, int crl_score)
1391 X509_NAME *nm = X509_CRL_get_issuer(crl);
1392 /* If no CRLissuer return is successful iff don't need a match */
1394 return ! !(crl_score & CRL_SCORE_ISSUER_NAME);
1395 for (i = 0; i < sk_GENERAL_NAME_num(dp->CRLissuer); i++) {
1396 GENERAL_NAME *gen = sk_GENERAL_NAME_value(dp->CRLissuer, i);
1397 if (gen->type != GEN_DIRNAME)
1399 if (!X509_NAME_cmp(gen->d.directoryName, nm))
1405 /* Check CRLDP and IDP */
1407 static int crl_crldp_check(X509 *x, X509_CRL *crl, int crl_score,
1408 unsigned int *preasons)
1411 if (crl->idp_flags & IDP_ONLYATTR)
1413 if (x->ex_flags & EXFLAG_CA) {
1414 if (crl->idp_flags & IDP_ONLYUSER)
1417 if (crl->idp_flags & IDP_ONLYCA)
1420 *preasons = crl->idp_reasons;
1421 for (i = 0; i < sk_DIST_POINT_num(x->crldp); i++) {
1422 DIST_POINT *dp = sk_DIST_POINT_value(x->crldp, i);
1423 if (crldp_check_crlissuer(dp, crl, crl_score)) {
1424 if (!crl->idp || idp_check_dp(dp->distpoint, crl->idp->distpoint)) {
1425 *preasons &= dp->dp_reasons;
1430 if ((!crl->idp || !crl->idp->distpoint)
1431 && (crl_score & CRL_SCORE_ISSUER_NAME))
1437 * Retrieve CRL corresponding to current certificate. If deltas enabled try
1438 * to find a delta CRL too
1441 static int get_crl_delta(X509_STORE_CTX *ctx,
1442 X509_CRL **pcrl, X509_CRL **pdcrl, X509 *x)
1445 X509 *issuer = NULL;
1447 unsigned int reasons;
1448 X509_CRL *crl = NULL, *dcrl = NULL;
1449 STACK_OF(X509_CRL) *skcrl;
1450 X509_NAME *nm = X509_get_issuer_name(x);
1452 reasons = ctx->current_reasons;
1453 ok = get_crl_sk(ctx, &crl, &dcrl,
1454 &issuer, &crl_score, &reasons, ctx->crls);
1458 /* Lookup CRLs from store */
1460 skcrl = ctx->lookup_crls(ctx, nm);
1462 /* If no CRLs found and a near match from get_crl_sk use that */
1466 get_crl_sk(ctx, &crl, &dcrl, &issuer, &crl_score, &reasons, skcrl);
1468 sk_X509_CRL_pop_free(skcrl, X509_CRL_free);
1471 /* If we got any kind of CRL use it and return success */
1473 ctx->current_issuer = issuer;
1474 ctx->current_crl_score = crl_score;
1475 ctx->current_reasons = reasons;
1483 /* Check CRL validity */
1484 static int check_crl(X509_STORE_CTX *ctx, X509_CRL *crl)
1486 X509 *issuer = NULL;
1487 EVP_PKEY *ikey = NULL;
1488 int cnum = ctx->error_depth;
1489 int chnum = sk_X509_num(ctx->chain) - 1;
1491 /* if we have an alternative CRL issuer cert use that */
1492 if (ctx->current_issuer)
1493 issuer = ctx->current_issuer;
1495 * Else find CRL issuer: if not last certificate then issuer is next
1496 * certificate in chain.
1498 else if (cnum < chnum)
1499 issuer = sk_X509_value(ctx->chain, cnum + 1);
1501 issuer = sk_X509_value(ctx->chain, chnum);
1502 /* If not self signed, can't check signature */
1503 if (!ctx->check_issued(ctx, issuer, issuer) &&
1504 !verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL_ISSUER))
1512 * Skip most tests for deltas because they have already been done
1514 if (!crl->base_crl_number) {
1515 /* Check for cRLSign bit if keyUsage present */
1516 if ((issuer->ex_flags & EXFLAG_KUSAGE) &&
1517 !(issuer->ex_kusage & KU_CRL_SIGN) &&
1518 !verify_cb_crl(ctx, X509_V_ERR_KEYUSAGE_NO_CRL_SIGN))
1521 if (!(ctx->current_crl_score & CRL_SCORE_SCOPE) &&
1522 !verify_cb_crl(ctx, X509_V_ERR_DIFFERENT_CRL_SCOPE))
1525 if (!(ctx->current_crl_score & CRL_SCORE_SAME_PATH) &&
1526 check_crl_path(ctx, ctx->current_issuer) <= 0 &&
1527 !verify_cb_crl(ctx, X509_V_ERR_CRL_PATH_VALIDATION_ERROR))
1530 if ((crl->idp_flags & IDP_INVALID) &&
1531 !verify_cb_crl(ctx, X509_V_ERR_INVALID_EXTENSION))
1535 if (!(ctx->current_crl_score & CRL_SCORE_TIME) &&
1536 !check_crl_time(ctx, crl, 1))
1539 /* Attempt to get issuer certificate public key */
1540 ikey = X509_get0_pubkey(issuer);
1543 !verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY))
1547 int rv = X509_CRL_check_suiteb(crl, ikey, ctx->param->flags);
1549 if (rv != X509_V_OK && !verify_cb_crl(ctx, rv))
1551 /* Verify CRL signature */
1552 if (X509_CRL_verify(crl, ikey) <= 0 &&
1553 !verify_cb_crl(ctx, X509_V_ERR_CRL_SIGNATURE_FAILURE))
1559 /* Check certificate against CRL */
1560 static int cert_crl(X509_STORE_CTX *ctx, X509_CRL *crl, X509 *x)
1565 * The rules changed for this... previously if a CRL contained unhandled
1566 * critical extensions it could still be used to indicate a certificate
1567 * was revoked. This has since been changed since critical extensions can
1568 * change the meaning of CRL entries.
1570 if (!(ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL)
1571 && (crl->flags & EXFLAG_CRITICAL) &&
1572 !verify_cb_crl(ctx, X509_V_ERR_UNHANDLED_CRITICAL_CRL_EXTENSION))
1575 * Look for serial number of certificate in CRL. If found, make sure
1576 * reason is not removeFromCRL.
1578 if (X509_CRL_get0_by_cert(crl, &rev, x)) {
1579 if (rev->reason == CRL_REASON_REMOVE_FROM_CRL)
1581 if (!verify_cb_crl(ctx, X509_V_ERR_CERT_REVOKED))
1588 static int check_policy(X509_STORE_CTX *ctx)
1595 * With DANE, the trust anchor might be a bare public key, not a
1596 * certificate! In that case our chain does not have the trust anchor
1597 * certificate as a top-most element. This comports well with RFC5280
1598 * chain verification, since there too, the trust anchor is not part of the
1599 * chain to be verified. In particular, X509_policy_check() does not look
1600 * at the TA cert, but assumes that it is present as the top-most chain
1601 * element. We therefore temporarily push a NULL cert onto the chain if it
1602 * was verified via a bare public key, and pop it off right after the
1603 * X509_policy_check() call.
1605 if (ctx->bare_ta_signed && !sk_X509_push(ctx->chain, NULL)) {
1606 X509err(X509_F_CHECK_POLICY, ERR_R_MALLOC_FAILURE);
1607 ctx->error = X509_V_ERR_OUT_OF_MEM;
1610 ret = X509_policy_check(&ctx->tree, &ctx->explicit_policy, ctx->chain,
1611 ctx->param->policies, ctx->param->flags);
1612 if (ctx->bare_ta_signed)
1613 sk_X509_pop(ctx->chain);
1615 if (ret == X509_PCY_TREE_INTERNAL) {
1616 X509err(X509_F_CHECK_POLICY, ERR_R_MALLOC_FAILURE);
1617 ctx->error = X509_V_ERR_OUT_OF_MEM;
1620 /* Invalid or inconsistent extensions */
1621 if (ret == X509_PCY_TREE_INVALID) {
1624 /* Locate certificates with bad extensions and notify callback. */
1625 for (i = 1; i < sk_X509_num(ctx->chain); i++) {
1626 X509 *x = sk_X509_value(ctx->chain, i);
1628 if (!(x->ex_flags & EXFLAG_INVALID_POLICY))
1630 if (!verify_cb_cert(ctx, x, i,
1631 X509_V_ERR_INVALID_POLICY_EXTENSION))
1636 if (ret == X509_PCY_TREE_FAILURE) {
1637 ctx->current_cert = NULL;
1638 ctx->error = X509_V_ERR_NO_EXPLICIT_POLICY;
1639 return ctx->verify_cb(0, ctx);
1641 if (ret != X509_PCY_TREE_VALID) {
1642 X509err(X509_F_CHECK_POLICY, ERR_R_INTERNAL_ERROR);
1646 if (ctx->param->flags & X509_V_FLAG_NOTIFY_POLICY) {
1647 ctx->current_cert = NULL;
1649 * Verification errors need to be "sticky", a callback may have allowed
1650 * an SSL handshake to continue despite an error, and we must then
1651 * remain in an error state. Therefore, we MUST NOT clear earlier
1652 * verification errors by setting the error to X509_V_OK.
1654 if (!ctx->verify_cb(2, ctx))
1662 * Check certificate validity times.
1663 * If depth >= 0, invoke verification callbacks on error, otherwise just return
1664 * the validation status.
1666 * Return 1 on success, 0 otherwise.
1668 int x509_check_cert_time(X509_STORE_CTX *ctx, X509 *x, int depth)
1673 if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME)
1674 ptime = &ctx->param->check_time;
1675 else if (ctx->param->flags & X509_V_FLAG_NO_CHECK_TIME)
1680 i = X509_cmp_time(X509_get0_notBefore(x), ptime);
1681 if (i >= 0 && depth < 0)
1683 if (i == 0 && !verify_cb_cert(ctx, x, depth,
1684 X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD))
1686 if (i > 0 && !verify_cb_cert(ctx, x, depth, X509_V_ERR_CERT_NOT_YET_VALID))
1689 i = X509_cmp_time(X509_get0_notAfter(x), ptime);
1690 if (i <= 0 && depth < 0)
1692 if (i == 0 && !verify_cb_cert(ctx, x, depth,
1693 X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD))
1695 if (i < 0 && !verify_cb_cert(ctx, x, depth, X509_V_ERR_CERT_HAS_EXPIRED))
1700 static int internal_verify(X509_STORE_CTX *ctx)
1702 int n = sk_X509_num(ctx->chain) - 1;
1703 X509 *xi = sk_X509_value(ctx->chain, n);
1707 * With DANE-verified bare public key TA signatures, it remains only to
1708 * check the timestamps of the top certificate. We report the issuer as
1709 * NULL, since all we have is a bare key.
1711 if (ctx->bare_ta_signed) {
1717 if (ctx->check_issued(ctx, xi, xi))
1720 if (ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) {
1725 return verify_cb_cert(ctx, xi, 0,
1726 X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE);
1728 ctx->error_depth = n;
1729 xs = sk_X509_value(ctx->chain, n);
1733 * Do not clear ctx->error=0, it must be "sticky", only the user's callback
1734 * is allowed to reset errors (at its own peril).
1740 * Skip signature check for self signed certificates unless explicitly
1741 * asked for. It doesn't add any security and just wastes time. If
1742 * the issuer's public key is unusable, report the issuer certificate
1743 * and its depth (rather than the depth of the subject).
1745 if (xs != xi || (ctx->param->flags & X509_V_FLAG_CHECK_SS_SIGNATURE)) {
1746 if ((pkey = X509_get0_pubkey(xi)) == NULL) {
1747 if (!verify_cb_cert(ctx, xi, xi != xs ? n+1 : n,
1748 X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY))
1750 } else if (X509_verify(xs, pkey) <= 0) {
1751 if (!verify_cb_cert(ctx, xs, n,
1752 X509_V_ERR_CERT_SIGNATURE_FAILURE))
1758 /* Calls verify callback as needed */
1759 if (!x509_check_cert_time(ctx, xs, n))
1763 * Signal success at this depth. However, the previous error (if any)
1766 ctx->current_issuer = xi;
1767 ctx->current_cert = xs;
1768 ctx->error_depth = n;
1769 if (!ctx->verify_cb(1, ctx))
1774 xs = sk_X509_value(ctx->chain, n);
1780 int X509_cmp_current_time(const ASN1_TIME *ctm)
1782 return X509_cmp_time(ctm, NULL);
1785 int X509_cmp_time(const ASN1_TIME *ctm, time_t *cmp_time)
1787 static const size_t utctime_length = sizeof("YYMMDDHHMMSSZ") - 1;
1788 static const size_t generalizedtime_length = sizeof("YYYYMMDDHHMMSSZ") - 1;
1789 ASN1_TIME *asn1_cmp_time = NULL;
1790 int i, day, sec, ret = 0;
1791 #ifdef CHARSET_EBCDIC
1792 const char upper_z = 0x5A;
1794 const char upper_z = 'Z';
1797 * Note that ASN.1 allows much more slack in the time format than RFC5280.
1798 * In RFC5280, the representation is fixed:
1799 * UTCTime: YYMMDDHHMMSSZ
1800 * GeneralizedTime: YYYYMMDDHHMMSSZ
1802 * We do NOT currently enforce the following RFC 5280 requirement:
1803 * "CAs conforming to this profile MUST always encode certificate
1804 * validity dates through the year 2049 as UTCTime; certificate validity
1805 * dates in 2050 or later MUST be encoded as GeneralizedTime."
1807 switch (ctm->type) {
1808 case V_ASN1_UTCTIME:
1809 if (ctm->length != (int)(utctime_length))
1812 case V_ASN1_GENERALIZEDTIME:
1813 if (ctm->length != (int)(generalizedtime_length))
1821 * Verify the format: the ASN.1 functions we use below allow a more
1822 * flexible format than what's mandated by RFC 5280.
1823 * Digit and date ranges will be verified in the conversion methods.
1825 for (i = 0; i < ctm->length - 1; i++) {
1826 if (!ascii_isdigit(ctm->data[i]))
1829 if (ctm->data[ctm->length - 1] != upper_z)
1833 * There is ASN1_UTCTIME_cmp_time_t but no
1834 * ASN1_GENERALIZEDTIME_cmp_time_t or ASN1_TIME_cmp_time_t,
1835 * so we go through ASN.1
1837 asn1_cmp_time = X509_time_adj(NULL, 0, cmp_time);
1838 if (asn1_cmp_time == NULL)
1840 if (!ASN1_TIME_diff(&day, &sec, ctm, asn1_cmp_time))
1844 * X509_cmp_time comparison is <=.
1845 * The return value 0 is reserved for errors.
1847 ret = (day >= 0 && sec >= 0) ? -1 : 1;
1850 ASN1_TIME_free(asn1_cmp_time);
1855 * Return 0 if time should not be checked or reference time is in range,
1856 * or else 1 if it is past the end, or -1 if it is before the start
1858 int X509_cmp_timeframe(const X509_VERIFY_PARAM *vpm,
1859 const ASN1_TIME *start, const ASN1_TIME *end)
1862 time_t *time = NULL;
1863 unsigned long flags = vpm == NULL ? 0 : X509_VERIFY_PARAM_get_flags(vpm);
1865 if ((flags & X509_V_FLAG_USE_CHECK_TIME) != 0) {
1866 ref_time = X509_VERIFY_PARAM_get_time(vpm);
1868 } else if ((flags & X509_V_FLAG_NO_CHECK_TIME) != 0) {
1869 return 0; /* this means ok */
1870 } /* else reference time is the current time */
1872 if (end != NULL && X509_cmp_time(end, time) < 0)
1874 if (start != NULL && X509_cmp_time(start, time) > 0)
1879 ASN1_TIME *X509_gmtime_adj(ASN1_TIME *s, long adj)
1881 return X509_time_adj(s, adj, NULL);
1884 ASN1_TIME *X509_time_adj(ASN1_TIME *s, long offset_sec, time_t *in_tm)
1886 return X509_time_adj_ex(s, 0, offset_sec, in_tm);
1889 ASN1_TIME *X509_time_adj_ex(ASN1_TIME *s,
1890 int offset_day, long offset_sec, time_t *in_tm)
1899 if (s && !(s->flags & ASN1_STRING_FLAG_MSTRING)) {
1900 if (s->type == V_ASN1_UTCTIME)
1901 return ASN1_UTCTIME_adj(s, t, offset_day, offset_sec);
1902 if (s->type == V_ASN1_GENERALIZEDTIME)
1903 return ASN1_GENERALIZEDTIME_adj(s, t, offset_day, offset_sec);
1905 return ASN1_TIME_adj(s, t, offset_day, offset_sec);
1908 int X509_get_pubkey_parameters(EVP_PKEY *pkey, STACK_OF(X509) *chain)
1910 EVP_PKEY *ktmp = NULL, *ktmp2;
1913 if ((pkey != NULL) && !EVP_PKEY_missing_parameters(pkey))
1916 for (i = 0; i < sk_X509_num(chain); i++) {
1917 ktmp = X509_get0_pubkey(sk_X509_value(chain, i));
1919 X509err(X509_F_X509_GET_PUBKEY_PARAMETERS,
1920 X509_R_UNABLE_TO_GET_CERTS_PUBLIC_KEY);
1923 if (!EVP_PKEY_missing_parameters(ktmp))
1927 X509err(X509_F_X509_GET_PUBKEY_PARAMETERS,
1928 X509_R_UNABLE_TO_FIND_PARAMETERS_IN_CHAIN);
1932 /* first, populate the other certs */
1933 for (j = i - 1; j >= 0; j--) {
1934 ktmp2 = X509_get0_pubkey(sk_X509_value(chain, j));
1935 EVP_PKEY_copy_parameters(ktmp2, ktmp);
1939 EVP_PKEY_copy_parameters(pkey, ktmp);
1943 /* Make a delta CRL as the diff between two full CRLs */
1945 X509_CRL *X509_CRL_diff(X509_CRL *base, X509_CRL *newer,
1946 EVP_PKEY *skey, const EVP_MD *md, unsigned int flags)
1948 X509_CRL *crl = NULL;
1950 STACK_OF(X509_REVOKED) *revs = NULL;
1951 /* CRLs can't be delta already */
1952 if (base->base_crl_number || newer->base_crl_number) {
1953 X509err(X509_F_X509_CRL_DIFF, X509_R_CRL_ALREADY_DELTA);
1956 /* Base and new CRL must have a CRL number */
1957 if (!base->crl_number || !newer->crl_number) {
1958 X509err(X509_F_X509_CRL_DIFF, X509_R_NO_CRL_NUMBER);
1961 /* Issuer names must match */
1962 if (X509_NAME_cmp(X509_CRL_get_issuer(base), X509_CRL_get_issuer(newer))) {
1963 X509err(X509_F_X509_CRL_DIFF, X509_R_ISSUER_MISMATCH);
1966 /* AKID and IDP must match */
1967 if (!crl_extension_match(base, newer, NID_authority_key_identifier)) {
1968 X509err(X509_F_X509_CRL_DIFF, X509_R_AKID_MISMATCH);
1971 if (!crl_extension_match(base, newer, NID_issuing_distribution_point)) {
1972 X509err(X509_F_X509_CRL_DIFF, X509_R_IDP_MISMATCH);
1975 /* Newer CRL number must exceed full CRL number */
1976 if (ASN1_INTEGER_cmp(newer->crl_number, base->crl_number) <= 0) {
1977 X509err(X509_F_X509_CRL_DIFF, X509_R_NEWER_CRL_NOT_NEWER);
1980 /* CRLs must verify */
1981 if (skey && (X509_CRL_verify(base, skey) <= 0 ||
1982 X509_CRL_verify(newer, skey) <= 0)) {
1983 X509err(X509_F_X509_CRL_DIFF, X509_R_CRL_VERIFY_FAILURE);
1986 /* Create new CRL */
1987 crl = X509_CRL_new();
1988 if (crl == NULL || !X509_CRL_set_version(crl, 1))
1990 /* Set issuer name */
1991 if (!X509_CRL_set_issuer_name(crl, X509_CRL_get_issuer(newer)))
1994 if (!X509_CRL_set1_lastUpdate(crl, X509_CRL_get0_lastUpdate(newer)))
1996 if (!X509_CRL_set1_nextUpdate(crl, X509_CRL_get0_nextUpdate(newer)))
1999 /* Set base CRL number: must be critical */
2001 if (!X509_CRL_add1_ext_i2d(crl, NID_delta_crl, base->crl_number, 1, 0))
2005 * Copy extensions across from newest CRL to delta: this will set CRL
2006 * number to correct value too.
2009 for (i = 0; i < X509_CRL_get_ext_count(newer); i++) {
2010 X509_EXTENSION *ext;
2011 ext = X509_CRL_get_ext(newer, i);
2012 if (!X509_CRL_add_ext(crl, ext, -1))
2016 /* Go through revoked entries, copying as needed */
2018 revs = X509_CRL_get_REVOKED(newer);
2020 for (i = 0; i < sk_X509_REVOKED_num(revs); i++) {
2021 X509_REVOKED *rvn, *rvtmp;
2022 rvn = sk_X509_REVOKED_value(revs, i);
2024 * Add only if not also in base. TODO: need something cleverer here
2025 * for some more complex CRLs covering multiple CAs.
2027 if (!X509_CRL_get0_by_serial(base, &rvtmp, &rvn->serialNumber)) {
2028 rvtmp = X509_REVOKED_dup(rvn);
2031 if (!X509_CRL_add0_revoked(crl, rvtmp)) {
2032 X509_REVOKED_free(rvtmp);
2037 /* TODO: optionally prune deleted entries */
2039 if (skey && md && !X509_CRL_sign(crl, skey, md))
2045 X509err(X509_F_X509_CRL_DIFF, ERR_R_MALLOC_FAILURE);
2050 int X509_STORE_CTX_set_ex_data(X509_STORE_CTX *ctx, int idx, void *data)
2052 return CRYPTO_set_ex_data(&ctx->ex_data, idx, data);
2055 void *X509_STORE_CTX_get_ex_data(X509_STORE_CTX *ctx, int idx)
2057 return CRYPTO_get_ex_data(&ctx->ex_data, idx);
2060 int X509_STORE_CTX_get_error(X509_STORE_CTX *ctx)
2065 void X509_STORE_CTX_set_error(X509_STORE_CTX *ctx, int err)
2070 int X509_STORE_CTX_get_error_depth(X509_STORE_CTX *ctx)
2072 return ctx->error_depth;
2075 void X509_STORE_CTX_set_error_depth(X509_STORE_CTX *ctx, int depth)
2077 ctx->error_depth = depth;
2080 X509 *X509_STORE_CTX_get_current_cert(X509_STORE_CTX *ctx)
2082 return ctx->current_cert;
2085 void X509_STORE_CTX_set_current_cert(X509_STORE_CTX *ctx, X509 *x)
2087 ctx->current_cert = x;
2090 STACK_OF(X509) *X509_STORE_CTX_get0_chain(X509_STORE_CTX *ctx)
2095 STACK_OF(X509) *X509_STORE_CTX_get1_chain(X509_STORE_CTX *ctx)
2099 return X509_chain_up_ref(ctx->chain);
2102 X509 *X509_STORE_CTX_get0_current_issuer(X509_STORE_CTX *ctx)
2104 return ctx->current_issuer;
2107 X509_CRL *X509_STORE_CTX_get0_current_crl(X509_STORE_CTX *ctx)
2109 return ctx->current_crl;
2112 X509_STORE_CTX *X509_STORE_CTX_get0_parent_ctx(X509_STORE_CTX *ctx)
2117 void X509_STORE_CTX_set_cert(X509_STORE_CTX *ctx, X509 *x)
2122 void X509_STORE_CTX_set0_crls(X509_STORE_CTX *ctx, STACK_OF(X509_CRL) *sk)
2127 int X509_STORE_CTX_set_purpose(X509_STORE_CTX *ctx, int purpose)
2130 * XXX: Why isn't this function always used to set the associated trust?
2131 * Should there even be a VPM->trust field at all? Or should the trust
2132 * always be inferred from the purpose by X509_STORE_CTX_init().
2134 return X509_STORE_CTX_purpose_inherit(ctx, 0, purpose, 0);
2137 int X509_STORE_CTX_set_trust(X509_STORE_CTX *ctx, int trust)
2140 * XXX: See above, this function would only be needed when the default
2141 * trust for the purpose needs an override in a corner case.
2143 return X509_STORE_CTX_purpose_inherit(ctx, 0, 0, trust);
2147 * This function is used to set the X509_STORE_CTX purpose and trust values.
2148 * This is intended to be used when another structure has its own trust and
2149 * purpose values which (if set) will be inherited by the ctx. If they aren't
2150 * set then we will usually have a default purpose in mind which should then
2151 * be used to set the trust value. An example of this is SSL use: an SSL
2152 * structure will have its own purpose and trust settings which the
2153 * application can set: if they aren't set then we use the default of SSL
2157 int X509_STORE_CTX_purpose_inherit(X509_STORE_CTX *ctx, int def_purpose,
2158 int purpose, int trust)
2161 /* If purpose not set use default */
2163 purpose = def_purpose;
2164 /* If we have a purpose then check it is valid */
2167 idx = X509_PURPOSE_get_by_id(purpose);
2169 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2170 X509_R_UNKNOWN_PURPOSE_ID);
2173 ptmp = X509_PURPOSE_get0(idx);
2174 if (ptmp->trust == X509_TRUST_DEFAULT) {
2175 idx = X509_PURPOSE_get_by_id(def_purpose);
2177 * XXX: In the two callers above def_purpose is always 0, which is
2178 * not a known value, so idx will always be -1. How is the
2179 * X509_TRUST_DEFAULT case actually supposed to be handled?
2182 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2183 X509_R_UNKNOWN_PURPOSE_ID);
2186 ptmp = X509_PURPOSE_get0(idx);
2188 /* If trust not set then get from purpose default */
2190 trust = ptmp->trust;
2193 idx = X509_TRUST_get_by_id(trust);
2195 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2196 X509_R_UNKNOWN_TRUST_ID);
2201 if (purpose && !ctx->param->purpose)
2202 ctx->param->purpose = purpose;
2203 if (trust && !ctx->param->trust)
2204 ctx->param->trust = trust;
2208 X509_STORE_CTX *X509_STORE_CTX_new(void)
2210 X509_STORE_CTX *ctx = OPENSSL_zalloc(sizeof(*ctx));
2213 X509err(X509_F_X509_STORE_CTX_NEW, ERR_R_MALLOC_FAILURE);
2219 void X509_STORE_CTX_free(X509_STORE_CTX *ctx)
2224 X509_STORE_CTX_cleanup(ctx);
2228 int X509_STORE_CTX_init(X509_STORE_CTX *ctx, X509_STORE *store, X509 *x509,
2229 STACK_OF(X509) *chain)
2235 ctx->untrusted = chain;
2237 ctx->num_untrusted = 0;
2238 ctx->other_ctx = NULL;
2242 ctx->explicit_policy = 0;
2243 ctx->error_depth = 0;
2244 ctx->current_cert = NULL;
2245 ctx->current_issuer = NULL;
2246 ctx->current_crl = NULL;
2247 ctx->current_crl_score = 0;
2248 ctx->current_reasons = 0;
2252 ctx->bare_ta_signed = 0;
2253 /* Zero ex_data to make sure we're cleanup-safe */
2254 memset(&ctx->ex_data, 0, sizeof(ctx->ex_data));
2256 /* store->cleanup is always 0 in OpenSSL, if set must be idempotent */
2258 ctx->cleanup = store->cleanup;
2262 if (store && store->check_issued)
2263 ctx->check_issued = store->check_issued;
2265 ctx->check_issued = check_issued;
2267 if (store && store->get_issuer)
2268 ctx->get_issuer = store->get_issuer;
2270 ctx->get_issuer = X509_STORE_CTX_get1_issuer;
2272 if (store && store->verify_cb)
2273 ctx->verify_cb = store->verify_cb;
2275 ctx->verify_cb = null_callback;
2277 if (store && store->verify)
2278 ctx->verify = store->verify;
2280 ctx->verify = internal_verify;
2282 if (store && store->check_revocation)
2283 ctx->check_revocation = store->check_revocation;
2285 ctx->check_revocation = check_revocation;
2287 if (store && store->get_crl)
2288 ctx->get_crl = store->get_crl;
2290 ctx->get_crl = NULL;
2292 if (store && store->check_crl)
2293 ctx->check_crl = store->check_crl;
2295 ctx->check_crl = check_crl;
2297 if (store && store->cert_crl)
2298 ctx->cert_crl = store->cert_crl;
2300 ctx->cert_crl = cert_crl;
2302 if (store && store->check_policy)
2303 ctx->check_policy = store->check_policy;
2305 ctx->check_policy = check_policy;
2307 if (store && store->lookup_certs)
2308 ctx->lookup_certs = store->lookup_certs;
2310 ctx->lookup_certs = X509_STORE_CTX_get1_certs;
2312 if (store && store->lookup_crls)
2313 ctx->lookup_crls = store->lookup_crls;
2315 ctx->lookup_crls = X509_STORE_CTX_get1_crls;
2317 ctx->param = X509_VERIFY_PARAM_new();
2318 if (ctx->param == NULL) {
2319 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2324 * Inherit callbacks and flags from X509_STORE if not set use defaults.
2327 ret = X509_VERIFY_PARAM_inherit(ctx->param, store->param);
2329 ctx->param->inh_flags |= X509_VP_FLAG_DEFAULT | X509_VP_FLAG_ONCE;
2332 ret = X509_VERIFY_PARAM_inherit(ctx->param,
2333 X509_VERIFY_PARAM_lookup("default"));
2336 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2341 * XXX: For now, continue to inherit trust from VPM, but infer from the
2342 * purpose if this still yields the default value.
2344 if (ctx->param->trust == X509_TRUST_DEFAULT) {
2345 int idx = X509_PURPOSE_get_by_id(ctx->param->purpose);
2346 X509_PURPOSE *xp = X509_PURPOSE_get0(idx);
2349 ctx->param->trust = X509_PURPOSE_get_trust(xp);
2352 if (CRYPTO_new_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx,
2355 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2359 * On error clean up allocated storage, if the store context was not
2360 * allocated with X509_STORE_CTX_new() this is our last chance to do so.
2362 X509_STORE_CTX_cleanup(ctx);
2367 * Set alternative lookup method: just a STACK of trusted certificates. This
2368 * avoids X509_STORE nastiness where it isn't needed.
2370 void X509_STORE_CTX_set0_trusted_stack(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2372 ctx->other_ctx = sk;
2373 ctx->get_issuer = get_issuer_sk;
2374 ctx->lookup_certs = lookup_certs_sk;
2377 void X509_STORE_CTX_cleanup(X509_STORE_CTX *ctx)
2380 * We need to be idempotent because, unfortunately, free() also calls
2381 * cleanup(), so the natural call sequence new(), init(), cleanup(), free()
2382 * calls cleanup() for the same object twice! Thus we must zero the
2383 * pointers below after they're freed!
2385 /* Seems to always be 0 in OpenSSL, do this at most once. */
2386 if (ctx->cleanup != NULL) {
2388 ctx->cleanup = NULL;
2390 if (ctx->param != NULL) {
2391 if (ctx->parent == NULL)
2392 X509_VERIFY_PARAM_free(ctx->param);
2395 X509_policy_tree_free(ctx->tree);
2397 sk_X509_pop_free(ctx->chain, X509_free);
2399 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx, &(ctx->ex_data));
2400 memset(&ctx->ex_data, 0, sizeof(ctx->ex_data));
2403 void X509_STORE_CTX_set_depth(X509_STORE_CTX *ctx, int depth)
2405 X509_VERIFY_PARAM_set_depth(ctx->param, depth);
2408 void X509_STORE_CTX_set_flags(X509_STORE_CTX *ctx, unsigned long flags)
2410 X509_VERIFY_PARAM_set_flags(ctx->param, flags);
2413 void X509_STORE_CTX_set_time(X509_STORE_CTX *ctx, unsigned long flags,
2416 X509_VERIFY_PARAM_set_time(ctx->param, t);
2419 X509 *X509_STORE_CTX_get0_cert(X509_STORE_CTX *ctx)
2424 STACK_OF(X509) *X509_STORE_CTX_get0_untrusted(X509_STORE_CTX *ctx)
2426 return ctx->untrusted;
2429 void X509_STORE_CTX_set0_untrusted(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2431 ctx->untrusted = sk;
2434 void X509_STORE_CTX_set0_verified_chain(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2436 sk_X509_pop_free(ctx->chain, X509_free);
2440 void X509_STORE_CTX_set_verify_cb(X509_STORE_CTX *ctx,
2441 X509_STORE_CTX_verify_cb verify_cb)
2443 ctx->verify_cb = verify_cb;
2446 X509_STORE_CTX_verify_cb X509_STORE_CTX_get_verify_cb(X509_STORE_CTX *ctx)
2448 return ctx->verify_cb;
2451 void X509_STORE_CTX_set_verify(X509_STORE_CTX *ctx,
2452 X509_STORE_CTX_verify_fn verify)
2454 ctx->verify = verify;
2457 X509_STORE_CTX_verify_fn X509_STORE_CTX_get_verify(X509_STORE_CTX *ctx)
2462 X509_STORE_CTX_get_issuer_fn X509_STORE_CTX_get_get_issuer(X509_STORE_CTX *ctx)
2464 return ctx->get_issuer;
2467 X509_STORE_CTX_check_issued_fn X509_STORE_CTX_get_check_issued(X509_STORE_CTX *ctx)
2469 return ctx->check_issued;
2472 X509_STORE_CTX_check_revocation_fn X509_STORE_CTX_get_check_revocation(X509_STORE_CTX *ctx)
2474 return ctx->check_revocation;
2477 X509_STORE_CTX_get_crl_fn X509_STORE_CTX_get_get_crl(X509_STORE_CTX *ctx)
2479 return ctx->get_crl;
2482 X509_STORE_CTX_check_crl_fn X509_STORE_CTX_get_check_crl(X509_STORE_CTX *ctx)
2484 return ctx->check_crl;
2487 X509_STORE_CTX_cert_crl_fn X509_STORE_CTX_get_cert_crl(X509_STORE_CTX *ctx)
2489 return ctx->cert_crl;
2492 X509_STORE_CTX_check_policy_fn X509_STORE_CTX_get_check_policy(X509_STORE_CTX *ctx)
2494 return ctx->check_policy;
2497 X509_STORE_CTX_lookup_certs_fn X509_STORE_CTX_get_lookup_certs(X509_STORE_CTX *ctx)
2499 return ctx->lookup_certs;
2502 X509_STORE_CTX_lookup_crls_fn X509_STORE_CTX_get_lookup_crls(X509_STORE_CTX *ctx)
2504 return ctx->lookup_crls;
2507 X509_STORE_CTX_cleanup_fn X509_STORE_CTX_get_cleanup(X509_STORE_CTX *ctx)
2509 return ctx->cleanup;
2512 X509_POLICY_TREE *X509_STORE_CTX_get0_policy_tree(X509_STORE_CTX *ctx)
2517 int X509_STORE_CTX_get_explicit_policy(X509_STORE_CTX *ctx)
2519 return ctx->explicit_policy;
2522 int X509_STORE_CTX_get_num_untrusted(X509_STORE_CTX *ctx)
2524 return ctx->num_untrusted;
2527 int X509_STORE_CTX_set_default(X509_STORE_CTX *ctx, const char *name)
2529 const X509_VERIFY_PARAM *param;
2531 param = X509_VERIFY_PARAM_lookup(name);
2534 return X509_VERIFY_PARAM_inherit(ctx->param, param);
2537 X509_VERIFY_PARAM *X509_STORE_CTX_get0_param(X509_STORE_CTX *ctx)
2542 void X509_STORE_CTX_set0_param(X509_STORE_CTX *ctx, X509_VERIFY_PARAM *param)
2544 X509_VERIFY_PARAM_free(ctx->param);
2548 void X509_STORE_CTX_set0_dane(X509_STORE_CTX *ctx, SSL_DANE *dane)
2553 static unsigned char *dane_i2d(
2556 unsigned int *i2dlen)
2558 unsigned char *buf = NULL;
2562 * Extract ASN.1 DER form of certificate or public key.
2565 case DANETLS_SELECTOR_CERT:
2566 len = i2d_X509(cert, &buf);
2568 case DANETLS_SELECTOR_SPKI:
2569 len = i2d_X509_PUBKEY(X509_get_X509_PUBKEY(cert), &buf);
2572 X509err(X509_F_DANE_I2D, X509_R_BAD_SELECTOR);
2576 if (len < 0 || buf == NULL) {
2577 X509err(X509_F_DANE_I2D, ERR_R_MALLOC_FAILURE);
2581 *i2dlen = (unsigned int)len;
2585 #define DANETLS_NONE 256 /* impossible uint8_t */
2587 static int dane_match(X509_STORE_CTX *ctx, X509 *cert, int depth)
2589 SSL_DANE *dane = ctx->dane;
2590 unsigned usage = DANETLS_NONE;
2591 unsigned selector = DANETLS_NONE;
2592 unsigned ordinal = DANETLS_NONE;
2593 unsigned mtype = DANETLS_NONE;
2594 unsigned char *i2dbuf = NULL;
2595 unsigned int i2dlen = 0;
2596 unsigned char mdbuf[EVP_MAX_MD_SIZE];
2597 unsigned char *cmpbuf = NULL;
2598 unsigned int cmplen = 0;
2602 danetls_record *t = NULL;
2605 mask = (depth == 0) ? DANETLS_EE_MASK : DANETLS_TA_MASK;
2608 * The trust store is not applicable with DANE-TA(2)
2610 if (depth >= ctx->num_untrusted)
2611 mask &= DANETLS_PKIX_MASK;
2614 * If we've previously matched a PKIX-?? record, no need to test any
2615 * further PKIX-?? records, it remains to just build the PKIX chain.
2616 * Had the match been a DANE-?? record, we'd be done already.
2618 if (dane->mdpth >= 0)
2619 mask &= ~DANETLS_PKIX_MASK;
2622 * https://tools.ietf.org/html/rfc7671#section-5.1
2623 * https://tools.ietf.org/html/rfc7671#section-5.2
2624 * https://tools.ietf.org/html/rfc7671#section-5.3
2625 * https://tools.ietf.org/html/rfc7671#section-5.4
2627 * We handle DANE-EE(3) records first as they require no chain building
2628 * and no expiration or hostname checks. We also process digests with
2629 * higher ordinals first and ignore lower priorities except Full(0) which
2630 * is always processed (last). If none match, we then process PKIX-EE(1).
2632 * NOTE: This relies on DANE usages sorting before the corresponding PKIX
2633 * usages in SSL_dane_tlsa_add(), and also on descending sorting of digest
2634 * priorities. See twin comment in ssl/ssl_lib.c.
2636 * We expect that most TLSA RRsets will have just a single usage, so we
2637 * don't go out of our way to cache multiple selector-specific i2d buffers
2638 * across usages, but if the selector happens to remain the same as switch
2639 * usages, that's OK. Thus, a set of "3 1 1", "3 0 1", "1 1 1", "1 0 1",
2640 * records would result in us generating each of the certificate and public
2641 * key DER forms twice, but more typically we'd just see multiple "3 1 1"
2642 * or multiple "3 0 1" records.
2644 * As soon as we find a match at any given depth, we stop, because either
2645 * we've matched a DANE-?? record and the peer is authenticated, or, after
2646 * exhausting all DANE-?? records, we've matched a PKIX-?? record, which is
2647 * sufficient for DANE, and what remains to do is ordinary PKIX validation.
2649 recnum = (dane->umask & mask) ? sk_danetls_record_num(dane->trecs) : 0;
2650 for (i = 0; matched == 0 && i < recnum; ++i) {
2651 t = sk_danetls_record_value(dane->trecs, i);
2652 if ((DANETLS_USAGE_BIT(t->usage) & mask) == 0)
2654 if (t->usage != usage) {
2657 /* Reset digest agility for each usage/selector pair */
2658 mtype = DANETLS_NONE;
2659 ordinal = dane->dctx->mdord[t->mtype];
2661 if (t->selector != selector) {
2662 selector = t->selector;
2664 /* Update per-selector state */
2665 OPENSSL_free(i2dbuf);
2666 i2dbuf = dane_i2d(cert, selector, &i2dlen);
2670 /* Reset digest agility for each usage/selector pair */
2671 mtype = DANETLS_NONE;
2672 ordinal = dane->dctx->mdord[t->mtype];
2673 } else if (t->mtype != DANETLS_MATCHING_FULL) {
2677 * <https://tools.ietf.org/html/rfc7671#section-9>
2679 * For a fixed selector, after processing all records with the
2680 * highest mtype ordinal, ignore all mtypes with lower ordinals
2681 * other than "Full".
2683 if (dane->dctx->mdord[t->mtype] < ordinal)
2688 * Each time we hit a (new selector or) mtype, re-compute the relevant
2689 * digest, more complex caching is not worth the code space.
2691 if (t->mtype != mtype) {
2692 const EVP_MD *md = dane->dctx->mdevp[mtype = t->mtype];
2698 if (!EVP_Digest(i2dbuf, i2dlen, cmpbuf, &cmplen, md, 0)) {
2706 * Squirrel away the certificate and depth if we have a match. Any
2707 * DANE match is dispositive, but with PKIX we still need to build a
2710 if (cmplen == t->dlen &&
2711 memcmp(cmpbuf, t->data, cmplen) == 0) {
2712 if (DANETLS_USAGE_BIT(usage) & DANETLS_DANE_MASK)
2714 if (matched || dane->mdpth < 0) {
2715 dane->mdpth = depth;
2717 OPENSSL_free(dane->mcert);
2725 /* Clear the one-element DER cache */
2726 OPENSSL_free(i2dbuf);
2730 static int check_dane_issuer(X509_STORE_CTX *ctx, int depth)
2732 SSL_DANE *dane = ctx->dane;
2736 if (!DANETLS_HAS_TA(dane) || depth == 0)
2737 return X509_TRUST_UNTRUSTED;
2740 * Record any DANE trust-anchor matches, for the first depth to test, if
2741 * there's one at that depth. (This'll be false for length 1 chains looking
2742 * for an exact match for the leaf certificate).
2744 cert = sk_X509_value(ctx->chain, depth);
2745 if (cert != NULL && (matched = dane_match(ctx, cert, depth)) < 0)
2746 return X509_TRUST_REJECTED;
2748 ctx->num_untrusted = depth - 1;
2749 return X509_TRUST_TRUSTED;
2752 return X509_TRUST_UNTRUSTED;
2755 static int check_dane_pkeys(X509_STORE_CTX *ctx)
2757 SSL_DANE *dane = ctx->dane;
2759 int num = ctx->num_untrusted;
2760 X509 *cert = sk_X509_value(ctx->chain, num - 1);
2761 int recnum = sk_danetls_record_num(dane->trecs);
2764 for (i = 0; i < recnum; ++i) {
2765 t = sk_danetls_record_value(dane->trecs, i);
2766 if (t->usage != DANETLS_USAGE_DANE_TA ||
2767 t->selector != DANETLS_SELECTOR_SPKI ||
2768 t->mtype != DANETLS_MATCHING_FULL ||
2769 X509_verify(cert, t->spki) <= 0)
2772 /* Clear any PKIX-?? matches that failed to extend to a full chain */
2773 X509_free(dane->mcert);
2776 /* Record match via a bare TA public key */
2777 ctx->bare_ta_signed = 1;
2778 dane->mdpth = num - 1;
2781 /* Prune any excess chain certificates */
2782 num = sk_X509_num(ctx->chain);
2783 for (; num > ctx->num_untrusted; --num)
2784 X509_free(sk_X509_pop(ctx->chain));
2786 return X509_TRUST_TRUSTED;
2789 return X509_TRUST_UNTRUSTED;
2792 static void dane_reset(SSL_DANE *dane)
2795 * Reset state to verify another chain, or clear after failure.
2797 X509_free(dane->mcert);
2804 static int check_leaf_suiteb(X509_STORE_CTX *ctx, X509 *cert)
2806 int err = X509_chain_check_suiteb(NULL, cert, NULL, ctx->param->flags);
2808 if (err == X509_V_OK)
2810 return verify_cb_cert(ctx, cert, 0, err);
2813 static int dane_verify(X509_STORE_CTX *ctx)
2815 X509 *cert = ctx->cert;
2816 SSL_DANE *dane = ctx->dane;
2823 * When testing the leaf certificate, if we match a DANE-EE(3) record,
2824 * dane_match() returns 1 and we're done. If however we match a PKIX-EE(1)
2825 * record, the match depth and matching TLSA record are recorded, but the
2826 * return value is 0, because we still need to find a PKIX trust-anchor.
2827 * Therefore, when DANE authentication is enabled (required), we're done
2829 * + matched < 0, internal error.
2830 * + matched == 1, we matched a DANE-EE(3) record
2831 * + matched == 0, mdepth < 0 (no PKIX-EE match) and there are no
2832 * DANE-TA(2) or PKIX-TA(0) to test.
2834 matched = dane_match(ctx, ctx->cert, 0);
2835 done = matched != 0 || (!DANETLS_HAS_TA(dane) && dane->mdpth < 0);
2838 X509_get_pubkey_parameters(NULL, ctx->chain);
2841 /* Callback invoked as needed */
2842 if (!check_leaf_suiteb(ctx, cert))
2844 /* Callback invoked as needed */
2845 if ((dane->flags & DANE_FLAG_NO_DANE_EE_NAMECHECKS) == 0 &&
2848 /* Bypass internal_verify(), issue depth 0 success callback */
2849 ctx->error_depth = 0;
2850 ctx->current_cert = cert;
2851 return ctx->verify_cb(1, ctx);
2855 ctx->error_depth = 0;
2856 ctx->current_cert = cert;
2857 ctx->error = X509_V_ERR_OUT_OF_MEM;
2862 /* Fail early, TA-based success is not possible */
2863 if (!check_leaf_suiteb(ctx, cert))
2865 return verify_cb_cert(ctx, cert, 0, X509_V_ERR_DANE_NO_MATCH);
2869 * Chain verification for usages 0/1/2. TLSA record matching of depth > 0
2870 * certificates happens in-line with building the rest of the chain.
2872 return verify_chain(ctx);
2875 /* Get issuer, without duplicate suppression */
2876 static int get_issuer(X509 **issuer, X509_STORE_CTX *ctx, X509 *cert)
2878 STACK_OF(X509) *saved_chain = ctx->chain;
2882 ok = ctx->get_issuer(issuer, ctx, cert);
2883 ctx->chain = saved_chain;
2888 static int build_chain(X509_STORE_CTX *ctx)
2890 SSL_DANE *dane = ctx->dane;
2891 int num = sk_X509_num(ctx->chain);
2892 X509 *cert = sk_X509_value(ctx->chain, num - 1);
2893 int ss = cert_self_signed(cert);
2894 STACK_OF(X509) *sktmp = NULL;
2895 unsigned int search;
2896 int may_trusted = 0;
2897 int may_alternate = 0;
2898 int trust = X509_TRUST_UNTRUSTED;
2899 int alt_untrusted = 0;
2904 /* Our chain starts with a single untrusted element. */
2905 if (!ossl_assert(num == 1 && ctx->num_untrusted == num)) {
2906 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
2907 ctx->error = X509_V_ERR_UNSPECIFIED;
2911 #define S_DOUNTRUSTED (1 << 0) /* Search untrusted chain */
2912 #define S_DOTRUSTED (1 << 1) /* Search trusted store */
2913 #define S_DOALTERNATE (1 << 2) /* Retry with pruned alternate chain */
2915 * Set up search policy, untrusted if possible, trusted-first if enabled.
2916 * If we're doing DANE and not doing PKIX-TA/PKIX-EE, we never look in the
2917 * trust_store, otherwise we might look there first. If not trusted-first,
2918 * and alternate chains are not disabled, try building an alternate chain
2919 * if no luck with untrusted first.
2921 search = (ctx->untrusted != NULL) ? S_DOUNTRUSTED : 0;
2922 if (DANETLS_HAS_PKIX(dane) || !DANETLS_HAS_DANE(dane)) {
2923 if (search == 0 || ctx->param->flags & X509_V_FLAG_TRUSTED_FIRST)
2924 search |= S_DOTRUSTED;
2925 else if (!(ctx->param->flags & X509_V_FLAG_NO_ALT_CHAINS))
2931 * Shallow-copy the stack of untrusted certificates (with TLS, this is
2932 * typically the content of the peer's certificate message) so can make
2933 * multiple passes over it, while free to remove elements as we go.
2935 if (ctx->untrusted && (sktmp = sk_X509_dup(ctx->untrusted)) == NULL) {
2936 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2937 ctx->error = X509_V_ERR_OUT_OF_MEM;
2942 * If we got any "DANE-TA(2) Cert(0) Full(0)" trust-anchors from DNS, add
2943 * them to our working copy of the untrusted certificate stack. Since the
2944 * caller of X509_STORE_CTX_init() may have provided only a leaf cert with
2945 * no corresponding stack of untrusted certificates, we may need to create
2946 * an empty stack first. [ At present only the ssl library provides DANE
2947 * support, and ssl_verify_cert_chain() always provides a non-null stack
2948 * containing at least the leaf certificate, but we must be prepared for
2951 if (DANETLS_ENABLED(dane) && dane->certs != NULL) {
2952 if (sktmp == NULL && (sktmp = sk_X509_new_null()) == NULL) {
2953 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2954 ctx->error = X509_V_ERR_OUT_OF_MEM;
2957 for (i = 0; i < sk_X509_num(dane->certs); ++i) {
2958 if (!sk_X509_push(sktmp, sk_X509_value(dane->certs, i))) {
2959 sk_X509_free(sktmp);
2960 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2961 ctx->error = X509_V_ERR_OUT_OF_MEM;
2968 * Still absurdly large, but arithmetically safe, a lower hard upper bound
2969 * might be reasonable.
2971 if (ctx->param->depth > INT_MAX/2)
2972 ctx->param->depth = INT_MAX/2;
2975 * Try to Extend the chain until we reach an ultimately trusted issuer.
2976 * Build chains up to one longer the limit, later fail if we hit the limit,
2977 * with an X509_V_ERR_CERT_CHAIN_TOO_LONG error code.
2979 depth = ctx->param->depth + 1;
2981 while (search != 0) {
2986 * Look in the trust store if enabled for first lookup, or we've run
2987 * out of untrusted issuers and search here is not disabled. When we
2988 * reach the depth limit, we stop extending the chain, if by that point
2989 * we've not found a trust-anchor, any trusted chain would be too long.
2991 * The error reported to the application verify callback is at the
2992 * maximal valid depth with the current certificate equal to the last
2993 * not ultimately-trusted issuer. For example, with verify_depth = 0,
2994 * the callback will report errors at depth=1 when the immediate issuer
2995 * of the leaf certificate is not a trust anchor. No attempt will be
2996 * made to locate an issuer for that certificate, since such a chain
2997 * would be a-priori too long.
2999 if ((search & S_DOTRUSTED) != 0) {
3000 i = num = sk_X509_num(ctx->chain);
3001 if ((search & S_DOALTERNATE) != 0) {
3003 * As high up the chain as we can, look for an alternative
3004 * trusted issuer of an untrusted certificate that currently
3005 * has an untrusted issuer. We use the alt_untrusted variable
3006 * to track how far up the chain we find the first match. It
3007 * is only if and when we find a match, that we prune the chain
3008 * and reset ctx->num_untrusted to the reduced count of
3009 * untrusted certificates. While we're searching for such a
3010 * match (which may never be found), it is neither safe nor
3011 * wise to preemptively modify either the chain or
3012 * ctx->num_untrusted.
3014 * Note, like ctx->num_untrusted, alt_untrusted is a count of
3015 * untrusted certificates, not a "depth".
3019 x = sk_X509_value(ctx->chain, i-1);
3021 ok = (depth < num) ? 0 : get_issuer(&xtmp, ctx, x);
3024 trust = X509_TRUST_REJECTED;
3025 ctx->error = X509_V_ERR_STORE_LOOKUP;
3032 * Alternative trusted issuer for a mid-chain untrusted cert?
3033 * Pop the untrusted cert's successors and retry. We might now
3034 * be able to complete a valid chain via the trust store. Note
3035 * that despite the current trust-store match we might still
3036 * fail complete the chain to a suitable trust-anchor, in which
3037 * case we may prune some more untrusted certificates and try
3038 * again. Thus the S_DOALTERNATE bit may yet be turned on
3039 * again with an even shorter untrusted chain!
3041 * If in the process we threw away our matching PKIX-TA trust
3042 * anchor, reset DANE trust. We might find a suitable trusted
3043 * certificate among the ones from the trust store.
3045 if ((search & S_DOALTERNATE) != 0) {
3046 if (!ossl_assert(num > i && i > 0 && ss == 0)) {
3047 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
3049 trust = X509_TRUST_REJECTED;
3050 ctx->error = X509_V_ERR_UNSPECIFIED;
3054 search &= ~S_DOALTERNATE;
3055 for (; num > i; --num)
3056 X509_free(sk_X509_pop(ctx->chain));
3057 ctx->num_untrusted = num;
3059 if (DANETLS_ENABLED(dane) &&
3060 dane->mdpth >= ctx->num_untrusted) {
3062 X509_free(dane->mcert);
3065 if (DANETLS_ENABLED(dane) &&
3066 dane->pdpth >= ctx->num_untrusted)
3071 * Self-signed untrusted certificates get replaced by their
3072 * trusted matching issuer. Otherwise, grow the chain.
3075 if (!sk_X509_push(ctx->chain, x = xtmp)) {
3077 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
3078 trust = X509_TRUST_REJECTED;
3079 ctx->error = X509_V_ERR_OUT_OF_MEM;
3083 ss = cert_self_signed(x);
3084 } else if (num == ctx->num_untrusted) {
3086 * We have a self-signed certificate that has the same
3087 * subject name (and perhaps keyid and/or serial number) as
3088 * a trust-anchor. We must have an exact match to avoid
3089 * possible impersonation via key substitution etc.
3091 if (X509_cmp(x, xtmp) != 0) {
3092 /* Self-signed untrusted mimic. */
3097 ctx->num_untrusted = --num;
3098 (void) sk_X509_set(ctx->chain, num, x = xtmp);
3103 * We've added a new trusted certificate to the chain, recheck
3104 * trust. If not done, and not self-signed look deeper.
3105 * Whether or not we're doing "trusted first", we no longer
3106 * look for untrusted certificates from the peer's chain.
3108 * At this point ctx->num_trusted and num must reflect the
3109 * correct number of untrusted certificates, since the DANE
3110 * logic in check_trust() depends on distinguishing CAs from
3111 * "the wire" from CAs from the trust store. In particular, the
3112 * certificate at depth "num" should be the new trusted
3113 * certificate with ctx->num_untrusted <= num.
3116 if (!ossl_assert(ctx->num_untrusted <= num)) {
3117 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
3118 trust = X509_TRUST_REJECTED;
3119 ctx->error = X509_V_ERR_UNSPECIFIED;
3123 search &= ~S_DOUNTRUSTED;
3124 switch (trust = check_trust(ctx, num)) {
3125 case X509_TRUST_TRUSTED:
3126 case X509_TRUST_REJECTED:
3136 * No dispositive decision, and either self-signed or no match, if
3137 * we were doing untrusted-first, and alt-chains are not disabled,
3138 * do that, by repeatedly losing one untrusted element at a time,
3139 * and trying to extend the shorted chain.
3141 if ((search & S_DOUNTRUSTED) == 0) {
3142 /* Continue search for a trusted issuer of a shorter chain? */
3143 if ((search & S_DOALTERNATE) != 0 && --alt_untrusted > 0)
3145 /* Still no luck and no fallbacks left? */
3146 if (!may_alternate || (search & S_DOALTERNATE) != 0 ||
3147 ctx->num_untrusted < 2)
3149 /* Search for a trusted issuer of a shorter chain */
3150 search |= S_DOALTERNATE;
3151 alt_untrusted = ctx->num_untrusted - 1;
3157 * Extend chain with peer-provided certificates
3159 if ((search & S_DOUNTRUSTED) != 0) {
3160 num = sk_X509_num(ctx->chain);
3161 if (!ossl_assert(num == ctx->num_untrusted)) {
3162 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
3163 trust = X509_TRUST_REJECTED;
3164 ctx->error = X509_V_ERR_UNSPECIFIED;
3168 x = sk_X509_value(ctx->chain, num-1);
3171 * Once we run out of untrusted issuers, we stop looking for more
3172 * and start looking only in the trust store if enabled.
3174 xtmp = (ss || depth < num) ? NULL : find_issuer(ctx, sktmp, x);
3176 search &= ~S_DOUNTRUSTED;
3178 search |= S_DOTRUSTED;
3182 /* Drop this issuer from future consideration */
3183 (void) sk_X509_delete_ptr(sktmp, xtmp);
3185 if (!sk_X509_push(ctx->chain, xtmp)) {
3186 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
3187 trust = X509_TRUST_REJECTED;
3188 ctx->error = X509_V_ERR_OUT_OF_MEM;
3193 X509_up_ref(x = xtmp);
3194 ++ctx->num_untrusted;
3195 ss = cert_self_signed(xtmp);
3198 * Check for DANE-TA trust of the topmost untrusted certificate.
3200 switch (trust = check_dane_issuer(ctx, ctx->num_untrusted - 1)) {
3201 case X509_TRUST_TRUSTED:
3202 case X509_TRUST_REJECTED:
3208 sk_X509_free(sktmp);
3211 * Last chance to make a trusted chain, either bare DANE-TA public-key
3212 * signers, or else direct leaf PKIX trust.
3214 num = sk_X509_num(ctx->chain);
3216 if (trust == X509_TRUST_UNTRUSTED && DANETLS_HAS_DANE_TA(dane))
3217 trust = check_dane_pkeys(ctx);
3218 if (trust == X509_TRUST_UNTRUSTED && num == ctx->num_untrusted)
3219 trust = check_trust(ctx, num);
3223 case X509_TRUST_TRUSTED:
3225 case X509_TRUST_REJECTED:
3226 /* Callback already issued */
3228 case X509_TRUST_UNTRUSTED:
3230 num = sk_X509_num(ctx->chain);
3232 return verify_cb_cert(ctx, NULL, num-1,
3233 X509_V_ERR_CERT_CHAIN_TOO_LONG);
3234 if (DANETLS_ENABLED(dane) &&
3235 (!DANETLS_HAS_PKIX(dane) || dane->pdpth >= 0))
3236 return verify_cb_cert(ctx, NULL, num-1, X509_V_ERR_DANE_NO_MATCH);
3237 if (ss && sk_X509_num(ctx->chain) == 1)
3238 return verify_cb_cert(ctx, NULL, num-1,
3239 X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT);
3241 return verify_cb_cert(ctx, NULL, num-1,
3242 X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN);
3243 if (ctx->num_untrusted < num)
3244 return verify_cb_cert(ctx, NULL, num-1,
3245 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT);
3246 return verify_cb_cert(ctx, NULL, num-1,
3247 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY);
3251 static const int minbits_table[] = { 80, 112, 128, 192, 256 };
3252 static const int NUM_AUTH_LEVELS = OSSL_NELEM(minbits_table);
3255 * Check whether the public key of ``cert`` meets the security level of
3258 * Returns 1 on success, 0 otherwise.
3260 static int check_key_level(X509_STORE_CTX *ctx, X509 *cert)
3262 EVP_PKEY *pkey = X509_get0_pubkey(cert);
3263 int level = ctx->param->auth_level;
3266 * At security level zero, return without checking for a supported public
3267 * key type. Some engines support key types not understood outside the
3268 * engine, and we only need to understand the key when enforcing a security
3274 /* Unsupported or malformed keys are not secure */
3278 if (level > NUM_AUTH_LEVELS)
3279 level = NUM_AUTH_LEVELS;
3281 return EVP_PKEY_security_bits(pkey) >= minbits_table[level - 1];
3285 * Check whether the signature digest algorithm of ``cert`` meets the security
3286 * level of ``ctx``. Should not be checked for trust anchors (whether
3287 * self-signed or otherwise).
3289 * Returns 1 on success, 0 otherwise.
3291 static int check_sig_level(X509_STORE_CTX *ctx, X509 *cert)
3294 int level = ctx->param->auth_level;
3298 if (level > NUM_AUTH_LEVELS)
3299 level = NUM_AUTH_LEVELS;
3301 if (!X509_get_signature_info(cert, NULL, NULL, &secbits, NULL))
3304 return secbits >= minbits_table[level - 1];