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"
28 /* CRL score values */
30 /* No unhandled critical extensions */
32 #define CRL_SCORE_NOCRITICAL 0x100
34 /* certificate is within CRL scope */
36 #define CRL_SCORE_SCOPE 0x080
40 #define CRL_SCORE_TIME 0x040
42 /* Issuer name matches certificate */
44 #define CRL_SCORE_ISSUER_NAME 0x020
46 /* If this score or above CRL is probably valid */
48 #define CRL_SCORE_VALID (CRL_SCORE_NOCRITICAL|CRL_SCORE_TIME|CRL_SCORE_SCOPE)
50 /* CRL issuer is certificate issuer */
52 #define CRL_SCORE_ISSUER_CERT 0x018
54 /* CRL issuer is on certificate path */
56 #define CRL_SCORE_SAME_PATH 0x008
58 /* CRL issuer matches CRL AKID */
60 #define CRL_SCORE_AKID 0x004
62 /* Have a delta CRL with valid times */
64 #define CRL_SCORE_TIME_DELTA 0x002
66 static int build_chain(X509_STORE_CTX *ctx);
67 static int verify_chain(X509_STORE_CTX *ctx);
68 static int dane_verify(X509_STORE_CTX *ctx);
69 static int null_callback(int ok, X509_STORE_CTX *e);
70 static int check_issued(X509_STORE_CTX *ctx, X509 *x, X509 *issuer);
71 static X509 *find_issuer(X509_STORE_CTX *ctx, STACK_OF(X509) *sk, X509 *x);
72 static int check_chain_extensions(X509_STORE_CTX *ctx);
73 static int check_name_constraints(X509_STORE_CTX *ctx);
74 static int check_id(X509_STORE_CTX *ctx);
75 static int check_trust(X509_STORE_CTX *ctx, int num_untrusted);
76 static int check_revocation(X509_STORE_CTX *ctx);
77 static int check_cert(X509_STORE_CTX *ctx);
78 static int check_policy(X509_STORE_CTX *ctx);
79 static int get_issuer_sk(X509 **issuer, X509_STORE_CTX *ctx, X509 *x);
80 static int check_dane_issuer(X509_STORE_CTX *ctx, int depth);
81 static int check_key_level(X509_STORE_CTX *ctx, X509 *cert);
82 static int check_sig_level(X509_STORE_CTX *ctx, X509 *cert);
84 static int get_crl_score(X509_STORE_CTX *ctx, X509 **pissuer,
85 unsigned int *preasons, X509_CRL *crl, X509 *x);
86 static int get_crl_delta(X509_STORE_CTX *ctx,
87 X509_CRL **pcrl, X509_CRL **pdcrl, X509 *x);
88 static void get_delta_sk(X509_STORE_CTX *ctx, X509_CRL **dcrl,
89 int *pcrl_score, X509_CRL *base,
90 STACK_OF(X509_CRL) *crls);
91 static void crl_akid_check(X509_STORE_CTX *ctx, X509_CRL *crl, X509 **pissuer,
93 static int crl_crldp_check(X509 *x, X509_CRL *crl, int crl_score,
94 unsigned int *preasons);
95 static int check_crl_path(X509_STORE_CTX *ctx, X509 *x);
96 static int check_crl_chain(X509_STORE_CTX *ctx,
97 STACK_OF(X509) *cert_path,
98 STACK_OF(X509) *crl_path);
100 static int internal_verify(X509_STORE_CTX *ctx);
102 static int null_callback(int ok, X509_STORE_CTX *e)
107 /* Return 1 is a certificate is self signed */
108 static int cert_self_signed(X509 *x)
110 if (X509_check_purpose(x, -1, 0) != 1)
112 if (x->ex_flags & EXFLAG_SS)
118 /* Given a certificate try and find an exact match in the store */
120 static X509 *lookup_cert_match(X509_STORE_CTX *ctx, X509 *x)
122 STACK_OF(X509) *certs;
125 /* Lookup all certs with matching subject name */
126 certs = ctx->lookup_certs(ctx, X509_get_subject_name(x));
129 /* Look for exact match */
130 for (i = 0; i < sk_X509_num(certs); i++) {
131 xtmp = sk_X509_value(certs, i);
132 if (!X509_cmp(xtmp, x))
135 if (i < sk_X509_num(certs))
139 sk_X509_pop_free(certs, X509_free);
144 * Inform the verify callback of an error.
145 * If B<x> is not NULL it is the error cert, otherwise use the chain cert at
147 * If B<err> is not X509_V_OK, that's the error value, otherwise leave
148 * unchanged (presumably set by the caller).
150 * Returns 0 to abort verification with an error, non-zero to continue.
152 static int verify_cb_cert(X509_STORE_CTX *ctx, X509 *x, int depth, int err)
154 ctx->error_depth = depth;
155 ctx->current_cert = (x != NULL) ? x : sk_X509_value(ctx->chain, depth);
156 if (err != X509_V_OK)
158 return ctx->verify_cb(0, ctx);
162 * Inform the verify callback of an error, CRL-specific variant. Here, the
163 * error depth and certificate are already set, we just specify the error
166 * Returns 0 to abort verification with an error, non-zero to continue.
168 static int verify_cb_crl(X509_STORE_CTX *ctx, int err)
171 return ctx->verify_cb(0, ctx);
174 static int check_auth_level(X509_STORE_CTX *ctx)
177 int num = sk_X509_num(ctx->chain);
179 if (ctx->param->auth_level <= 0)
182 for (i = 0; i < num; ++i) {
183 X509 *cert = sk_X509_value(ctx->chain, i);
186 * We've already checked the security of the leaf key, so here we only
187 * check the security of issuer keys.
189 if (i > 0 && !check_key_level(ctx, cert) &&
190 verify_cb_cert(ctx, cert, i, X509_V_ERR_CA_KEY_TOO_SMALL) == 0)
193 * We also check the signature algorithm security of all certificates
194 * except those of the trust anchor at index num-1.
196 if (i < num - 1 && !check_sig_level(ctx, cert) &&
197 verify_cb_cert(ctx, cert, i, X509_V_ERR_CA_MD_TOO_WEAK) == 0)
203 static int verify_chain(X509_STORE_CTX *ctx)
209 * Before either returning with an error, or continuing with CRL checks,
210 * instantiate chain public key parameters.
212 if ((ok = build_chain(ctx)) == 0 ||
213 (ok = check_chain_extensions(ctx)) == 0 ||
214 (ok = check_auth_level(ctx)) == 0 ||
215 (ok = check_id(ctx)) == 0 || 1)
216 X509_get_pubkey_parameters(NULL, ctx->chain);
217 if (ok == 0 || (ok = ctx->check_revocation(ctx)) == 0)
220 err = X509_chain_check_suiteb(&ctx->error_depth, NULL, ctx->chain,
222 if (err != X509_V_OK) {
223 if ((ok = verify_cb_cert(ctx, NULL, ctx->error_depth, err)) == 0)
227 /* Verify chain signatures and expiration times */
228 ok = (ctx->verify != NULL) ? ctx->verify(ctx) : internal_verify(ctx);
232 if ((ok = check_name_constraints(ctx)) == 0)
235 #ifndef OPENSSL_NO_RFC3779
236 /* RFC 3779 path validation, now that CRL check has been done */
237 if ((ok = X509v3_asid_validate_path(ctx)) == 0)
239 if ((ok = X509v3_addr_validate_path(ctx)) == 0)
243 /* If we get this far evaluate policies */
244 if (ctx->param->flags & X509_V_FLAG_POLICY_CHECK)
245 ok = ctx->check_policy(ctx);
249 int X509_verify_cert(X509_STORE_CTX *ctx)
251 SSL_DANE *dane = ctx->dane;
254 if (ctx->cert == NULL) {
255 X509err(X509_F_X509_VERIFY_CERT, X509_R_NO_CERT_SET_FOR_US_TO_VERIFY);
256 ctx->error = X509_V_ERR_INVALID_CALL;
260 if (ctx->chain != NULL) {
262 * This X509_STORE_CTX has already been used to verify a cert. We
263 * cannot do another one.
265 X509err(X509_F_X509_VERIFY_CERT, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
266 ctx->error = X509_V_ERR_INVALID_CALL;
271 * first we make sure the chain we are going to build is present and that
272 * the first entry is in place
274 if (((ctx->chain = sk_X509_new_null()) == NULL) ||
275 (!sk_X509_push(ctx->chain, ctx->cert))) {
276 X509err(X509_F_X509_VERIFY_CERT, ERR_R_MALLOC_FAILURE);
277 ctx->error = X509_V_ERR_OUT_OF_MEM;
280 X509_up_ref(ctx->cert);
281 ctx->num_untrusted = 1;
283 /* If the peer's public key is too weak, we can stop early. */
284 if (!check_key_level(ctx, ctx->cert) &&
285 !verify_cb_cert(ctx, ctx->cert, 0, X509_V_ERR_EE_KEY_TOO_SMALL))
288 if (DANETLS_ENABLED(dane))
289 ret = dane_verify(ctx);
291 ret = verify_chain(ctx);
294 * Safety-net. If we are returning an error, we must also set ctx->error,
295 * so that the chain is not considered verified should the error be ignored
296 * (e.g. TLS with SSL_VERIFY_NONE).
298 if (ret <= 0 && ctx->error == X509_V_OK)
299 ctx->error = X509_V_ERR_UNSPECIFIED;
304 * Given a STACK_OF(X509) find the issuer of cert (if any)
306 static X509 *find_issuer(X509_STORE_CTX *ctx, STACK_OF(X509) *sk, X509 *x)
309 X509 *issuer, *rv = NULL;
311 for (i = 0; i < sk_X509_num(sk); i++) {
312 issuer = sk_X509_value(sk, i);
313 if (ctx->check_issued(ctx, x, issuer)) {
315 if (x509_check_cert_time(ctx, rv, -1))
322 /* Given a possible certificate and issuer check them */
324 static int check_issued(X509_STORE_CTX *ctx, X509 *x, X509 *issuer)
328 return cert_self_signed(x);
329 ret = X509_check_issued(issuer, x);
330 if (ret == X509_V_OK) {
333 /* Special case: single self signed certificate */
334 if (cert_self_signed(x) && sk_X509_num(ctx->chain) == 1)
336 for (i = 0; i < sk_X509_num(ctx->chain); i++) {
337 ch = sk_X509_value(ctx->chain, i);
338 if (ch == issuer || !X509_cmp(ch, issuer)) {
339 ret = X509_V_ERR_PATH_LOOP;
345 return (ret == X509_V_OK);
348 /* Alternative lookup method: look from a STACK stored in other_ctx */
350 static int get_issuer_sk(X509 **issuer, X509_STORE_CTX *ctx, X509 *x)
352 *issuer = find_issuer(ctx, ctx->other_ctx, x);
354 X509_up_ref(*issuer);
360 static STACK_OF(X509) *lookup_certs_sk(X509_STORE_CTX *ctx,
363 STACK_OF(X509) *sk = NULL;
367 for (i = 0; i < sk_X509_num(ctx->other_ctx); i++) {
368 x = sk_X509_value(ctx->other_ctx, i);
369 if (X509_NAME_cmp(nm, X509_get_subject_name(x)) == 0) {
371 sk = sk_X509_new_null();
372 if (sk == NULL || sk_X509_push(sk, x) == 0) {
373 sk_X509_pop_free(sk, X509_free);
374 X509err(X509_F_LOOKUP_CERTS_SK, ERR_R_MALLOC_FAILURE);
375 ctx->error = X509_V_ERR_OUT_OF_MEM;
385 * Check EE or CA certificate purpose. For trusted certificates explicit local
386 * auxiliary trust can be used to override EKU-restrictions.
388 static int check_purpose(X509_STORE_CTX *ctx, X509 *x, int purpose, int depth,
391 int tr_ok = X509_TRUST_UNTRUSTED;
394 * For trusted certificates we want to see whether any auxiliary trust
395 * settings trump the purpose constraints.
397 * This is complicated by the fact that the trust ordinals in
398 * ctx->param->trust are entirely independent of the purpose ordinals in
399 * ctx->param->purpose!
401 * What connects them is their mutual initialization via calls from
402 * X509_STORE_CTX_set_default() into X509_VERIFY_PARAM_lookup() which sets
403 * related values of both param->trust and param->purpose. It is however
404 * typically possible to infer associated trust values from a purpose value
405 * via the X509_PURPOSE API.
407 * Therefore, we can only check for trust overrides when the purpose we're
408 * checking is the same as ctx->param->purpose and ctx->param->trust is
411 if (depth >= ctx->num_untrusted && purpose == ctx->param->purpose)
412 tr_ok = X509_check_trust(x, ctx->param->trust, X509_TRUST_NO_SS_COMPAT);
415 case X509_TRUST_TRUSTED:
417 case X509_TRUST_REJECTED:
420 switch (X509_check_purpose(x, purpose, must_be_ca > 0)) {
426 if ((ctx->param->flags & X509_V_FLAG_X509_STRICT) == 0)
432 return verify_cb_cert(ctx, x, depth, X509_V_ERR_INVALID_PURPOSE);
436 * Check a certificate chains extensions for consistency with the supplied
440 static int check_chain_extensions(X509_STORE_CTX *ctx)
442 int i, must_be_ca, plen = 0;
444 int proxy_path_length = 0;
446 int allow_proxy_certs;
447 int num = sk_X509_num(ctx->chain);
450 * must_be_ca can have 1 of 3 values:
451 * -1: we accept both CA and non-CA certificates, to allow direct
452 * use of self-signed certificates (which are marked as CA).
453 * 0: we only accept non-CA certificates. This is currently not
454 * used, but the possibility is present for future extensions.
455 * 1: we only accept CA certificates. This is currently used for
456 * all certificates in the chain except the leaf certificate.
460 /* CRL path validation */
462 allow_proxy_certs = 0;
463 purpose = X509_PURPOSE_CRL_SIGN;
466 ! !(ctx->param->flags & X509_V_FLAG_ALLOW_PROXY_CERTS);
467 purpose = ctx->param->purpose;
470 for (i = 0; i < num; i++) {
472 x = sk_X509_value(ctx->chain, i);
473 if (!(ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL)
474 && (x->ex_flags & EXFLAG_CRITICAL)) {
475 if (!verify_cb_cert(ctx, x, i,
476 X509_V_ERR_UNHANDLED_CRITICAL_EXTENSION))
479 if (!allow_proxy_certs && (x->ex_flags & EXFLAG_PROXY)) {
480 if (!verify_cb_cert(ctx, x, i,
481 X509_V_ERR_PROXY_CERTIFICATES_NOT_ALLOWED))
484 ret = X509_check_ca(x);
485 switch (must_be_ca) {
487 if ((ctx->param->flags & X509_V_FLAG_X509_STRICT)
488 && (ret != 1) && (ret != 0)) {
490 ctx->error = X509_V_ERR_INVALID_CA;
497 ctx->error = X509_V_ERR_INVALID_NON_CA;
502 /* X509_V_FLAG_X509_STRICT is implicit for intermediate CAs */
504 || ((i + 1 < num || ctx->param->flags & X509_V_FLAG_X509_STRICT)
507 ctx->error = X509_V_ERR_INVALID_CA;
512 if (ret == 0 && !verify_cb_cert(ctx, x, i, X509_V_OK))
514 /* check_purpose() makes the callback as needed */
515 if (purpose > 0 && !check_purpose(ctx, x, purpose, i, must_be_ca))
518 if ((i > 1) && (x->ex_pathlen != -1)
519 && (plen > (x->ex_pathlen + proxy_path_length))) {
520 if (!verify_cb_cert(ctx, x, i, X509_V_ERR_PATH_LENGTH_EXCEEDED))
523 /* Increment path length if not a self issued intermediate CA */
524 if (i > 0 && (x->ex_flags & EXFLAG_SI) == 0)
527 * If this certificate is a proxy certificate, the next certificate
528 * must be another proxy certificate or a EE certificate. If not,
529 * the next certificate must be a CA certificate.
531 if (x->ex_flags & EXFLAG_PROXY) {
533 * RFC3820, 4.1.3 (b)(1) stipulates that if pCPathLengthConstraint
534 * is less than max_path_length, the former should be copied to
535 * the latter, and 4.1.4 (a) stipulates that max_path_length
536 * should be verified to be larger than zero and decrement it.
538 * Because we're checking the certs in the reverse order, we start
539 * with verifying that proxy_path_length isn't larger than pcPLC,
540 * and copy the latter to the former if it is, and finally,
541 * increment proxy_path_length.
543 if (x->ex_pcpathlen != -1) {
544 if (proxy_path_length > x->ex_pcpathlen) {
545 if (!verify_cb_cert(ctx, x, i,
546 X509_V_ERR_PROXY_PATH_LENGTH_EXCEEDED))
549 proxy_path_length = x->ex_pcpathlen;
559 static int has_san_id(X509 *x, int gtype)
563 GENERAL_NAMES *gs = X509_get_ext_d2i(x, NID_subject_alt_name, NULL, NULL);
568 for (i = 0; i < sk_GENERAL_NAME_num(gs); i++) {
569 GENERAL_NAME *g = sk_GENERAL_NAME_value(gs, i);
571 if (g->type == gtype) {
576 GENERAL_NAMES_free(gs);
580 static int check_name_constraints(X509_STORE_CTX *ctx)
584 /* Check name constraints for all certificates */
585 for (i = sk_X509_num(ctx->chain) - 1; i >= 0; i--) {
586 X509 *x = sk_X509_value(ctx->chain, i);
589 /* Ignore self issued certs unless last in chain */
590 if (i && (x->ex_flags & EXFLAG_SI))
594 * Proxy certificates policy has an extra constraint, where the
595 * certificate subject MUST be the issuer with a single CN entry
597 * (RFC 3820: 3.4, 4.1.3 (a)(4))
599 if (x->ex_flags & EXFLAG_PROXY) {
600 X509_NAME *tmpsubject = X509_get_subject_name(x);
601 X509_NAME *tmpissuer = X509_get_issuer_name(x);
602 X509_NAME_ENTRY *tmpentry = NULL;
603 int last_object_nid = 0;
605 int last_object_loc = X509_NAME_entry_count(tmpsubject) - 1;
607 /* Check that there are at least two RDNs */
608 if (last_object_loc < 1) {
609 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
610 goto proxy_name_done;
614 * Check that there is exactly one more RDN in subject as
615 * there is in issuer.
617 if (X509_NAME_entry_count(tmpsubject)
618 != X509_NAME_entry_count(tmpissuer) + 1) {
619 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
620 goto proxy_name_done;
624 * Check that the last subject component isn't part of a
627 if (X509_NAME_ENTRY_set(X509_NAME_get_entry(tmpsubject,
629 == X509_NAME_ENTRY_set(X509_NAME_get_entry(tmpsubject,
630 last_object_loc - 1))) {
631 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
632 goto proxy_name_done;
636 * Check that the last subject RDN is a commonName, and that
637 * all the previous RDNs match the issuer exactly
639 tmpsubject = X509_NAME_dup(tmpsubject);
640 if (tmpsubject == NULL) {
641 X509err(X509_F_CHECK_NAME_CONSTRAINTS, ERR_R_MALLOC_FAILURE);
642 ctx->error = X509_V_ERR_OUT_OF_MEM;
647 X509_NAME_delete_entry(tmpsubject, last_object_loc);
649 OBJ_obj2nid(X509_NAME_ENTRY_get_object(tmpentry));
651 if (last_object_nid != NID_commonName
652 || X509_NAME_cmp(tmpsubject, tmpissuer) != 0) {
653 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
656 X509_NAME_ENTRY_free(tmpentry);
657 X509_NAME_free(tmpsubject);
661 && !verify_cb_cert(ctx, x, i, err))
666 * Check against constraints for all certificates higher in chain
667 * including trust anchor. Trust anchor not strictly speaking needed
668 * but if it includes constraints it is to be assumed it expects them
671 for (j = sk_X509_num(ctx->chain) - 1; j > i; j--) {
672 NAME_CONSTRAINTS *nc = sk_X509_value(ctx->chain, j)->nc;
675 int rv = NAME_CONSTRAINTS_check(x, nc);
677 /* If EE certificate check commonName too */
678 if (rv == X509_V_OK && i == 0
679 && (ctx->param->hostflags
680 & X509_CHECK_FLAG_NEVER_CHECK_SUBJECT) == 0
681 && ((ctx->param->hostflags
682 & X509_CHECK_FLAG_ALWAYS_CHECK_SUBJECT) != 0
683 || !has_san_id(x, GEN_DNS)))
684 rv = NAME_CONSTRAINTS_check_CN(x, nc);
689 case X509_V_ERR_OUT_OF_MEM:
692 if (!verify_cb_cert(ctx, x, i, rv))
702 static int check_id_error(X509_STORE_CTX *ctx, int errcode)
704 return verify_cb_cert(ctx, ctx->cert, 0, errcode);
707 static int check_hosts(X509 *x, X509_VERIFY_PARAM *vpm)
710 int n = sk_OPENSSL_STRING_num(vpm->hosts);
713 if (vpm->peername != NULL) {
714 OPENSSL_free(vpm->peername);
715 vpm->peername = NULL;
717 for (i = 0; i < n; ++i) {
718 name = sk_OPENSSL_STRING_value(vpm->hosts, i);
719 if (X509_check_host(x, name, 0, vpm->hostflags, &vpm->peername) > 0)
725 static int check_id(X509_STORE_CTX *ctx)
727 X509_VERIFY_PARAM *vpm = ctx->param;
729 if (vpm->hosts && check_hosts(x, vpm) <= 0) {
730 if (!check_id_error(ctx, X509_V_ERR_HOSTNAME_MISMATCH))
733 if (vpm->email && X509_check_email(x, vpm->email, vpm->emaillen, 0) <= 0) {
734 if (!check_id_error(ctx, X509_V_ERR_EMAIL_MISMATCH))
737 if (vpm->ip && X509_check_ip(x, vpm->ip, vpm->iplen, 0) <= 0) {
738 if (!check_id_error(ctx, X509_V_ERR_IP_ADDRESS_MISMATCH))
744 static int check_trust(X509_STORE_CTX *ctx, int num_untrusted)
749 SSL_DANE *dane = ctx->dane;
750 int num = sk_X509_num(ctx->chain);
754 * Check for a DANE issuer at depth 1 or greater, if it is a DANE-TA(2)
755 * match, we're done, otherwise we'll merely record the match depth.
757 if (DANETLS_HAS_TA(dane) && num_untrusted > 0 && num_untrusted < num) {
758 switch (trust = check_dane_issuer(ctx, num_untrusted)) {
759 case X509_TRUST_TRUSTED:
760 case X509_TRUST_REJECTED:
766 * Check trusted certificates in chain at depth num_untrusted and up.
767 * Note, that depths 0..num_untrusted-1 may also contain trusted
768 * certificates, but the caller is expected to have already checked those,
769 * and wants to incrementally check just any added since.
771 for (i = num_untrusted; i < num; i++) {
772 x = sk_X509_value(ctx->chain, i);
773 trust = X509_check_trust(x, ctx->param->trust, 0);
774 /* If explicitly trusted return trusted */
775 if (trust == X509_TRUST_TRUSTED)
777 if (trust == X509_TRUST_REJECTED)
782 * If we are looking at a trusted certificate, and accept partial chains,
783 * the chain is PKIX trusted.
785 if (num_untrusted < num) {
786 if (ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN)
788 return X509_TRUST_UNTRUSTED;
791 if (num_untrusted == num && ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) {
793 * Last-resort call with no new trusted certificates, check the leaf
794 * for a direct trust store match.
797 x = sk_X509_value(ctx->chain, i);
798 mx = lookup_cert_match(ctx, x);
800 return X509_TRUST_UNTRUSTED;
803 * Check explicit auxiliary trust/reject settings. If none are set,
804 * we'll accept X509_TRUST_UNTRUSTED when not self-signed.
806 trust = X509_check_trust(mx, ctx->param->trust, 0);
807 if (trust == X509_TRUST_REJECTED) {
812 /* Replace leaf with trusted match */
813 (void) sk_X509_set(ctx->chain, 0, mx);
815 ctx->num_untrusted = 0;
820 * If no trusted certs in chain at all return untrusted and allow
821 * standard (no issuer cert) etc errors to be indicated.
823 return X509_TRUST_UNTRUSTED;
826 if (!verify_cb_cert(ctx, x, i, X509_V_ERR_CERT_REJECTED))
827 return X509_TRUST_REJECTED;
828 return X509_TRUST_UNTRUSTED;
831 if (!DANETLS_ENABLED(dane))
832 return X509_TRUST_TRUSTED;
834 dane->pdpth = num_untrusted;
835 /* With DANE, PKIX alone is not trusted until we have both */
836 if (dane->mdpth >= 0)
837 return X509_TRUST_TRUSTED;
838 return X509_TRUST_UNTRUSTED;
841 static int check_revocation(X509_STORE_CTX *ctx)
843 int i = 0, last = 0, ok = 0;
844 if (!(ctx->param->flags & X509_V_FLAG_CRL_CHECK))
846 if (ctx->param->flags & X509_V_FLAG_CRL_CHECK_ALL)
847 last = sk_X509_num(ctx->chain) - 1;
849 /* If checking CRL paths this isn't the EE certificate */
854 for (i = 0; i <= last; i++) {
855 ctx->error_depth = i;
856 ok = check_cert(ctx);
863 static int check_cert(X509_STORE_CTX *ctx)
865 X509_CRL *crl = NULL, *dcrl = NULL;
867 int cnum = ctx->error_depth;
868 X509 *x = sk_X509_value(ctx->chain, cnum);
870 ctx->current_cert = x;
871 ctx->current_issuer = NULL;
872 ctx->current_crl_score = 0;
873 ctx->current_reasons = 0;
875 if (x->ex_flags & EXFLAG_PROXY)
878 while (ctx->current_reasons != CRLDP_ALL_REASONS) {
879 unsigned int last_reasons = ctx->current_reasons;
881 /* Try to retrieve relevant CRL */
883 ok = ctx->get_crl(ctx, &crl, x);
885 ok = get_crl_delta(ctx, &crl, &dcrl, x);
887 * If error looking up CRL, nothing we can do except notify callback
890 ok = verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL);
893 ctx->current_crl = crl;
894 ok = ctx->check_crl(ctx, crl);
899 ok = ctx->check_crl(ctx, dcrl);
902 ok = ctx->cert_crl(ctx, dcrl, x);
908 /* Don't look in full CRL if delta reason is removefromCRL */
910 ok = ctx->cert_crl(ctx, crl, x);
920 * If reasons not updated we won't get anywhere by another iteration,
923 if (last_reasons == ctx->current_reasons) {
924 ok = verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL);
932 ctx->current_crl = NULL;
936 /* Check CRL times against values in X509_STORE_CTX */
938 static int check_crl_time(X509_STORE_CTX *ctx, X509_CRL *crl, int notify)
944 ctx->current_crl = crl;
945 if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME)
946 ptime = &ctx->param->check_time;
947 else if (ctx->param->flags & X509_V_FLAG_NO_CHECK_TIME)
952 i = X509_cmp_time(X509_CRL_get0_lastUpdate(crl), ptime);
956 if (!verify_cb_crl(ctx, X509_V_ERR_ERROR_IN_CRL_LAST_UPDATE_FIELD))
963 if (!verify_cb_crl(ctx, X509_V_ERR_CRL_NOT_YET_VALID))
967 if (X509_CRL_get0_nextUpdate(crl)) {
968 i = X509_cmp_time(X509_CRL_get0_nextUpdate(crl), ptime);
973 if (!verify_cb_crl(ctx, X509_V_ERR_ERROR_IN_CRL_NEXT_UPDATE_FIELD))
976 /* Ignore expiry of base CRL is delta is valid */
977 if ((i < 0) && !(ctx->current_crl_score & CRL_SCORE_TIME_DELTA)) {
980 if (!verify_cb_crl(ctx, X509_V_ERR_CRL_HAS_EXPIRED))
986 ctx->current_crl = NULL;
991 static int get_crl_sk(X509_STORE_CTX *ctx, X509_CRL **pcrl, X509_CRL **pdcrl,
992 X509 **pissuer, int *pscore, unsigned int *preasons,
993 STACK_OF(X509_CRL) *crls)
995 int i, crl_score, best_score = *pscore;
996 unsigned int reasons, best_reasons = 0;
997 X509 *x = ctx->current_cert;
998 X509_CRL *crl, *best_crl = NULL;
999 X509 *crl_issuer = NULL, *best_crl_issuer = NULL;
1001 for (i = 0; i < sk_X509_CRL_num(crls); i++) {
1002 crl = sk_X509_CRL_value(crls, i);
1003 reasons = *preasons;
1004 crl_score = get_crl_score(ctx, &crl_issuer, &reasons, crl, x);
1005 if (crl_score < best_score || crl_score == 0)
1007 /* If current CRL is equivalent use it if it is newer */
1008 if (crl_score == best_score && best_crl != NULL) {
1010 if (ASN1_TIME_diff(&day, &sec, X509_CRL_get0_lastUpdate(best_crl),
1011 X509_CRL_get0_lastUpdate(crl)) == 0)
1014 * ASN1_TIME_diff never returns inconsistent signs for |day|
1017 if (day <= 0 && sec <= 0)
1021 best_crl_issuer = crl_issuer;
1022 best_score = crl_score;
1023 best_reasons = reasons;
1027 X509_CRL_free(*pcrl);
1029 *pissuer = best_crl_issuer;
1030 *pscore = best_score;
1031 *preasons = best_reasons;
1032 X509_CRL_up_ref(best_crl);
1033 X509_CRL_free(*pdcrl);
1035 get_delta_sk(ctx, pdcrl, pscore, best_crl, crls);
1038 if (best_score >= CRL_SCORE_VALID)
1045 * Compare two CRL extensions for delta checking purposes. They should be
1046 * both present or both absent. If both present all fields must be identical.
1049 static int crl_extension_match(X509_CRL *a, X509_CRL *b, int nid)
1051 ASN1_OCTET_STRING *exta, *extb;
1053 i = X509_CRL_get_ext_by_NID(a, nid, -1);
1055 /* Can't have multiple occurrences */
1056 if (X509_CRL_get_ext_by_NID(a, nid, i) != -1)
1058 exta = X509_EXTENSION_get_data(X509_CRL_get_ext(a, i));
1062 i = X509_CRL_get_ext_by_NID(b, nid, -1);
1066 if (X509_CRL_get_ext_by_NID(b, nid, i) != -1)
1068 extb = X509_EXTENSION_get_data(X509_CRL_get_ext(b, i));
1078 if (ASN1_OCTET_STRING_cmp(exta, extb))
1084 /* See if a base and delta are compatible */
1086 static int check_delta_base(X509_CRL *delta, X509_CRL *base)
1088 /* Delta CRL must be a delta */
1089 if (!delta->base_crl_number)
1091 /* Base must have a CRL number */
1092 if (!base->crl_number)
1094 /* Issuer names must match */
1095 if (X509_NAME_cmp(X509_CRL_get_issuer(base), X509_CRL_get_issuer(delta)))
1097 /* AKID and IDP must match */
1098 if (!crl_extension_match(delta, base, NID_authority_key_identifier))
1100 if (!crl_extension_match(delta, base, NID_issuing_distribution_point))
1102 /* Delta CRL base number must not exceed Full CRL number. */
1103 if (ASN1_INTEGER_cmp(delta->base_crl_number, base->crl_number) > 0)
1105 /* Delta CRL number must exceed full CRL number */
1106 if (ASN1_INTEGER_cmp(delta->crl_number, base->crl_number) > 0)
1112 * For a given base CRL find a delta... maybe extend to delta scoring or
1113 * retrieve a chain of deltas...
1116 static void get_delta_sk(X509_STORE_CTX *ctx, X509_CRL **dcrl, int *pscore,
1117 X509_CRL *base, STACK_OF(X509_CRL) *crls)
1121 if (!(ctx->param->flags & X509_V_FLAG_USE_DELTAS))
1123 if (!((ctx->current_cert->ex_flags | base->flags) & EXFLAG_FRESHEST))
1125 for (i = 0; i < sk_X509_CRL_num(crls); i++) {
1126 delta = sk_X509_CRL_value(crls, i);
1127 if (check_delta_base(delta, base)) {
1128 if (check_crl_time(ctx, delta, 0))
1129 *pscore |= CRL_SCORE_TIME_DELTA;
1130 X509_CRL_up_ref(delta);
1139 * For a given CRL return how suitable it is for the supplied certificate
1140 * 'x'. The return value is a mask of several criteria. If the issuer is not
1141 * the certificate issuer this is returned in *pissuer. The reasons mask is
1142 * also used to determine if the CRL is suitable: if no new reasons the CRL
1143 * is rejected, otherwise reasons is updated.
1146 static int get_crl_score(X509_STORE_CTX *ctx, X509 **pissuer,
1147 unsigned int *preasons, X509_CRL *crl, X509 *x)
1151 unsigned int tmp_reasons = *preasons, crl_reasons;
1153 /* First see if we can reject CRL straight away */
1155 /* Invalid IDP cannot be processed */
1156 if (crl->idp_flags & IDP_INVALID)
1158 /* Reason codes or indirect CRLs need extended CRL support */
1159 if (!(ctx->param->flags & X509_V_FLAG_EXTENDED_CRL_SUPPORT)) {
1160 if (crl->idp_flags & (IDP_INDIRECT | IDP_REASONS))
1162 } else if (crl->idp_flags & IDP_REASONS) {
1163 /* If no new reasons reject */
1164 if (!(crl->idp_reasons & ~tmp_reasons))
1167 /* Don't process deltas at this stage */
1168 else if (crl->base_crl_number)
1170 /* If issuer name doesn't match certificate need indirect CRL */
1171 if (X509_NAME_cmp(X509_get_issuer_name(x), X509_CRL_get_issuer(crl))) {
1172 if (!(crl->idp_flags & IDP_INDIRECT))
1175 crl_score |= CRL_SCORE_ISSUER_NAME;
1177 if (!(crl->flags & EXFLAG_CRITICAL))
1178 crl_score |= CRL_SCORE_NOCRITICAL;
1181 if (check_crl_time(ctx, crl, 0))
1182 crl_score |= CRL_SCORE_TIME;
1184 /* Check authority key ID and locate certificate issuer */
1185 crl_akid_check(ctx, crl, pissuer, &crl_score);
1187 /* If we can't locate certificate issuer at this point forget it */
1189 if (!(crl_score & CRL_SCORE_AKID))
1192 /* Check cert for matching CRL distribution points */
1194 if (crl_crldp_check(x, crl, crl_score, &crl_reasons)) {
1195 /* If no new reasons reject */
1196 if (!(crl_reasons & ~tmp_reasons))
1198 tmp_reasons |= crl_reasons;
1199 crl_score |= CRL_SCORE_SCOPE;
1202 *preasons = tmp_reasons;
1208 static void crl_akid_check(X509_STORE_CTX *ctx, X509_CRL *crl,
1209 X509 **pissuer, int *pcrl_score)
1211 X509 *crl_issuer = NULL;
1212 const X509_NAME *cnm = X509_CRL_get_issuer(crl);
1213 int cidx = ctx->error_depth;
1216 if (cidx != sk_X509_num(ctx->chain) - 1)
1219 crl_issuer = sk_X509_value(ctx->chain, cidx);
1221 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1222 if (*pcrl_score & CRL_SCORE_ISSUER_NAME) {
1223 *pcrl_score |= CRL_SCORE_AKID | CRL_SCORE_ISSUER_CERT;
1224 *pissuer = crl_issuer;
1229 for (cidx++; cidx < sk_X509_num(ctx->chain); cidx++) {
1230 crl_issuer = sk_X509_value(ctx->chain, cidx);
1231 if (X509_NAME_cmp(X509_get_subject_name(crl_issuer), cnm))
1233 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1234 *pcrl_score |= CRL_SCORE_AKID | CRL_SCORE_SAME_PATH;
1235 *pissuer = crl_issuer;
1240 /* Anything else needs extended CRL support */
1242 if (!(ctx->param->flags & X509_V_FLAG_EXTENDED_CRL_SUPPORT))
1246 * Otherwise the CRL issuer is not on the path. Look for it in the set of
1247 * untrusted certificates.
1249 for (i = 0; i < sk_X509_num(ctx->untrusted); i++) {
1250 crl_issuer = sk_X509_value(ctx->untrusted, i);
1251 if (X509_NAME_cmp(X509_get_subject_name(crl_issuer), cnm))
1253 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1254 *pissuer = crl_issuer;
1255 *pcrl_score |= CRL_SCORE_AKID;
1262 * Check the path of a CRL issuer certificate. This creates a new
1263 * X509_STORE_CTX and populates it with most of the parameters from the
1264 * parent. This could be optimised somewhat since a lot of path checking will
1265 * be duplicated by the parent, but this will rarely be used in practice.
1268 static int check_crl_path(X509_STORE_CTX *ctx, X509 *x)
1270 X509_STORE_CTX crl_ctx;
1273 /* Don't allow recursive CRL path validation */
1276 if (!X509_STORE_CTX_init(&crl_ctx, ctx->store, x, ctx->untrusted))
1279 crl_ctx.crls = ctx->crls;
1280 /* Copy verify params across */
1281 X509_STORE_CTX_set0_param(&crl_ctx, ctx->param);
1283 crl_ctx.parent = ctx;
1284 crl_ctx.verify_cb = ctx->verify_cb;
1286 /* Verify CRL issuer */
1287 ret = X509_verify_cert(&crl_ctx);
1291 /* Check chain is acceptable */
1292 ret = check_crl_chain(ctx, ctx->chain, crl_ctx.chain);
1294 X509_STORE_CTX_cleanup(&crl_ctx);
1299 * RFC3280 says nothing about the relationship between CRL path and
1300 * certificate path, which could lead to situations where a certificate could
1301 * be revoked or validated by a CA not authorised to do so. RFC5280 is more
1302 * strict and states that the two paths must end in the same trust anchor,
1303 * though some discussions remain... until this is resolved we use the
1307 static int check_crl_chain(X509_STORE_CTX *ctx,
1308 STACK_OF(X509) *cert_path,
1309 STACK_OF(X509) *crl_path)
1311 X509 *cert_ta, *crl_ta;
1312 cert_ta = sk_X509_value(cert_path, sk_X509_num(cert_path) - 1);
1313 crl_ta = sk_X509_value(crl_path, sk_X509_num(crl_path) - 1);
1314 if (!X509_cmp(cert_ta, crl_ta))
1320 * Check for match between two dist point names: three separate cases.
1321 * 1. Both are relative names and compare X509_NAME types.
1322 * 2. One full, one relative. Compare X509_NAME to GENERAL_NAMES.
1323 * 3. Both are full names and compare two GENERAL_NAMES.
1324 * 4. One is NULL: automatic match.
1327 static int idp_check_dp(DIST_POINT_NAME *a, DIST_POINT_NAME *b)
1329 X509_NAME *nm = NULL;
1330 GENERAL_NAMES *gens = NULL;
1331 GENERAL_NAME *gena, *genb;
1338 /* Case 1: two X509_NAME */
1342 if (!X509_NAME_cmp(a->dpname, b->dpname))
1347 /* Case 2: set name and GENERAL_NAMES appropriately */
1349 gens = b->name.fullname;
1350 } else if (b->type == 1) {
1353 /* Case 2: set name and GENERAL_NAMES appropriately */
1354 gens = a->name.fullname;
1358 /* Handle case 2 with one GENERAL_NAMES and one X509_NAME */
1360 for (i = 0; i < sk_GENERAL_NAME_num(gens); i++) {
1361 gena = sk_GENERAL_NAME_value(gens, i);
1362 if (gena->type != GEN_DIRNAME)
1364 if (!X509_NAME_cmp(nm, gena->d.directoryName))
1370 /* Else case 3: two GENERAL_NAMES */
1372 for (i = 0; i < sk_GENERAL_NAME_num(a->name.fullname); i++) {
1373 gena = sk_GENERAL_NAME_value(a->name.fullname, i);
1374 for (j = 0; j < sk_GENERAL_NAME_num(b->name.fullname); j++) {
1375 genb = sk_GENERAL_NAME_value(b->name.fullname, j);
1376 if (!GENERAL_NAME_cmp(gena, genb))
1385 static int crldp_check_crlissuer(DIST_POINT *dp, X509_CRL *crl, int crl_score)
1388 const X509_NAME *nm = X509_CRL_get_issuer(crl);
1389 /* If no CRLissuer return is successful iff don't need a match */
1391 return ! !(crl_score & CRL_SCORE_ISSUER_NAME);
1392 for (i = 0; i < sk_GENERAL_NAME_num(dp->CRLissuer); i++) {
1393 GENERAL_NAME *gen = sk_GENERAL_NAME_value(dp->CRLissuer, i);
1394 if (gen->type != GEN_DIRNAME)
1396 if (!X509_NAME_cmp(gen->d.directoryName, nm))
1402 /* Check CRLDP and IDP */
1404 static int crl_crldp_check(X509 *x, X509_CRL *crl, int crl_score,
1405 unsigned int *preasons)
1408 if (crl->idp_flags & IDP_ONLYATTR)
1410 if (x->ex_flags & EXFLAG_CA) {
1411 if (crl->idp_flags & IDP_ONLYUSER)
1414 if (crl->idp_flags & IDP_ONLYCA)
1417 *preasons = crl->idp_reasons;
1418 for (i = 0; i < sk_DIST_POINT_num(x->crldp); i++) {
1419 DIST_POINT *dp = sk_DIST_POINT_value(x->crldp, i);
1420 if (crldp_check_crlissuer(dp, crl, crl_score)) {
1421 if (!crl->idp || idp_check_dp(dp->distpoint, crl->idp->distpoint)) {
1422 *preasons &= dp->dp_reasons;
1427 if ((!crl->idp || !crl->idp->distpoint)
1428 && (crl_score & CRL_SCORE_ISSUER_NAME))
1434 * Retrieve CRL corresponding to current certificate. If deltas enabled try
1435 * to find a delta CRL too
1438 static int get_crl_delta(X509_STORE_CTX *ctx,
1439 X509_CRL **pcrl, X509_CRL **pdcrl, X509 *x)
1442 X509 *issuer = NULL;
1444 unsigned int reasons;
1445 X509_CRL *crl = NULL, *dcrl = NULL;
1446 STACK_OF(X509_CRL) *skcrl;
1447 const X509_NAME *nm = X509_get_issuer_name(x);
1449 reasons = ctx->current_reasons;
1450 ok = get_crl_sk(ctx, &crl, &dcrl,
1451 &issuer, &crl_score, &reasons, ctx->crls);
1455 /* Lookup CRLs from store */
1457 skcrl = ctx->lookup_crls(ctx, nm);
1459 /* If no CRLs found and a near match from get_crl_sk use that */
1463 get_crl_sk(ctx, &crl, &dcrl, &issuer, &crl_score, &reasons, skcrl);
1465 sk_X509_CRL_pop_free(skcrl, X509_CRL_free);
1468 /* If we got any kind of CRL use it and return success */
1470 ctx->current_issuer = issuer;
1471 ctx->current_crl_score = crl_score;
1472 ctx->current_reasons = reasons;
1480 /* Check CRL validity */
1481 static int check_crl(X509_STORE_CTX *ctx, X509_CRL *crl)
1483 X509 *issuer = NULL;
1484 EVP_PKEY *ikey = NULL;
1485 int cnum = ctx->error_depth;
1486 int chnum = sk_X509_num(ctx->chain) - 1;
1488 /* if we have an alternative CRL issuer cert use that */
1489 if (ctx->current_issuer)
1490 issuer = ctx->current_issuer;
1492 * Else find CRL issuer: if not last certificate then issuer is next
1493 * certificate in chain.
1495 else if (cnum < chnum)
1496 issuer = sk_X509_value(ctx->chain, cnum + 1);
1498 issuer = sk_X509_value(ctx->chain, chnum);
1499 /* If not self signed, can't check signature */
1500 if (!ctx->check_issued(ctx, issuer, issuer) &&
1501 !verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL_ISSUER))
1509 * Skip most tests for deltas because they have already been done
1511 if (!crl->base_crl_number) {
1512 /* Check for cRLSign bit if keyUsage present */
1513 if ((issuer->ex_flags & EXFLAG_KUSAGE) &&
1514 !(issuer->ex_kusage & KU_CRL_SIGN) &&
1515 !verify_cb_crl(ctx, X509_V_ERR_KEYUSAGE_NO_CRL_SIGN))
1518 if (!(ctx->current_crl_score & CRL_SCORE_SCOPE) &&
1519 !verify_cb_crl(ctx, X509_V_ERR_DIFFERENT_CRL_SCOPE))
1522 if (!(ctx->current_crl_score & CRL_SCORE_SAME_PATH) &&
1523 check_crl_path(ctx, ctx->current_issuer) <= 0 &&
1524 !verify_cb_crl(ctx, X509_V_ERR_CRL_PATH_VALIDATION_ERROR))
1527 if ((crl->idp_flags & IDP_INVALID) &&
1528 !verify_cb_crl(ctx, X509_V_ERR_INVALID_EXTENSION))
1532 if (!(ctx->current_crl_score & CRL_SCORE_TIME) &&
1533 !check_crl_time(ctx, crl, 1))
1536 /* Attempt to get issuer certificate public key */
1537 ikey = X509_get0_pubkey(issuer);
1540 !verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY))
1544 int rv = X509_CRL_check_suiteb(crl, ikey, ctx->param->flags);
1546 if (rv != X509_V_OK && !verify_cb_crl(ctx, rv))
1548 /* Verify CRL signature */
1549 if (X509_CRL_verify(crl, ikey) <= 0 &&
1550 !verify_cb_crl(ctx, X509_V_ERR_CRL_SIGNATURE_FAILURE))
1556 /* Check certificate against CRL */
1557 static int cert_crl(X509_STORE_CTX *ctx, X509_CRL *crl, X509 *x)
1562 * The rules changed for this... previously if a CRL contained unhandled
1563 * critical extensions it could still be used to indicate a certificate
1564 * was revoked. This has since been changed since critical extensions can
1565 * change the meaning of CRL entries.
1567 if (!(ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL)
1568 && (crl->flags & EXFLAG_CRITICAL) &&
1569 !verify_cb_crl(ctx, X509_V_ERR_UNHANDLED_CRITICAL_CRL_EXTENSION))
1572 * Look for serial number of certificate in CRL. If found, make sure
1573 * reason is not removeFromCRL.
1575 if (X509_CRL_get0_by_cert(crl, &rev, x)) {
1576 if (rev->reason == CRL_REASON_REMOVE_FROM_CRL)
1578 if (!verify_cb_crl(ctx, X509_V_ERR_CERT_REVOKED))
1585 static int check_policy(X509_STORE_CTX *ctx)
1592 * With DANE, the trust anchor might be a bare public key, not a
1593 * certificate! In that case our chain does not have the trust anchor
1594 * certificate as a top-most element. This comports well with RFC5280
1595 * chain verification, since there too, the trust anchor is not part of the
1596 * chain to be verified. In particular, X509_policy_check() does not look
1597 * at the TA cert, but assumes that it is present as the top-most chain
1598 * element. We therefore temporarily push a NULL cert onto the chain if it
1599 * was verified via a bare public key, and pop it off right after the
1600 * X509_policy_check() call.
1602 if (ctx->bare_ta_signed && !sk_X509_push(ctx->chain, NULL)) {
1603 X509err(X509_F_CHECK_POLICY, ERR_R_MALLOC_FAILURE);
1604 ctx->error = X509_V_ERR_OUT_OF_MEM;
1607 ret = X509_policy_check(&ctx->tree, &ctx->explicit_policy, ctx->chain,
1608 ctx->param->policies, ctx->param->flags);
1609 if (ctx->bare_ta_signed)
1610 sk_X509_pop(ctx->chain);
1612 if (ret == X509_PCY_TREE_INTERNAL) {
1613 X509err(X509_F_CHECK_POLICY, ERR_R_MALLOC_FAILURE);
1614 ctx->error = X509_V_ERR_OUT_OF_MEM;
1617 /* Invalid or inconsistent extensions */
1618 if (ret == X509_PCY_TREE_INVALID) {
1621 /* Locate certificates with bad extensions and notify callback. */
1622 for (i = 1; i < sk_X509_num(ctx->chain); i++) {
1623 X509 *x = sk_X509_value(ctx->chain, i);
1625 if (!(x->ex_flags & EXFLAG_INVALID_POLICY))
1627 if (!verify_cb_cert(ctx, x, i,
1628 X509_V_ERR_INVALID_POLICY_EXTENSION))
1633 if (ret == X509_PCY_TREE_FAILURE) {
1634 ctx->current_cert = NULL;
1635 ctx->error = X509_V_ERR_NO_EXPLICIT_POLICY;
1636 return ctx->verify_cb(0, ctx);
1638 if (ret != X509_PCY_TREE_VALID) {
1639 X509err(X509_F_CHECK_POLICY, ERR_R_INTERNAL_ERROR);
1643 if (ctx->param->flags & X509_V_FLAG_NOTIFY_POLICY) {
1644 ctx->current_cert = NULL;
1646 * Verification errors need to be "sticky", a callback may have allowed
1647 * an SSL handshake to continue despite an error, and we must then
1648 * remain in an error state. Therefore, we MUST NOT clear earlier
1649 * verification errors by setting the error to X509_V_OK.
1651 if (!ctx->verify_cb(2, ctx))
1659 * Check certificate validity times.
1660 * If depth >= 0, invoke verification callbacks on error, otherwise just return
1661 * the validation status.
1663 * Return 1 on success, 0 otherwise.
1665 int x509_check_cert_time(X509_STORE_CTX *ctx, X509 *x, int depth)
1670 if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME)
1671 ptime = &ctx->param->check_time;
1672 else if (ctx->param->flags & X509_V_FLAG_NO_CHECK_TIME)
1677 i = X509_cmp_time(X509_get0_notBefore(x), ptime);
1678 if (i >= 0 && depth < 0)
1680 if (i == 0 && !verify_cb_cert(ctx, x, depth,
1681 X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD))
1683 if (i > 0 && !verify_cb_cert(ctx, x, depth, X509_V_ERR_CERT_NOT_YET_VALID))
1686 i = X509_cmp_time(X509_get0_notAfter(x), ptime);
1687 if (i <= 0 && depth < 0)
1689 if (i == 0 && !verify_cb_cert(ctx, x, depth,
1690 X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD))
1692 if (i < 0 && !verify_cb_cert(ctx, x, depth, X509_V_ERR_CERT_HAS_EXPIRED))
1697 static int internal_verify(X509_STORE_CTX *ctx)
1699 int n = sk_X509_num(ctx->chain) - 1;
1700 X509 *xi = sk_X509_value(ctx->chain, n);
1704 * With DANE-verified bare public key TA signatures, it remains only to
1705 * check the timestamps of the top certificate. We report the issuer as
1706 * NULL, since all we have is a bare key.
1708 if (ctx->bare_ta_signed) {
1714 if (ctx->check_issued(ctx, xi, xi))
1717 if (ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) {
1722 return verify_cb_cert(ctx, xi, 0,
1723 X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE);
1725 ctx->error_depth = n;
1726 xs = sk_X509_value(ctx->chain, n);
1730 * Do not clear ctx->error=0, it must be "sticky", only the user's callback
1731 * is allowed to reset errors (at its own peril).
1737 * Skip signature check for self signed certificates unless explicitly
1738 * asked for. It doesn't add any security and just wastes time. If
1739 * the issuer's public key is unusable, report the issuer certificate
1740 * and its depth (rather than the depth of the subject).
1742 if (xs != xi || (ctx->param->flags & X509_V_FLAG_CHECK_SS_SIGNATURE)) {
1743 if ((pkey = X509_get0_pubkey(xi)) == NULL) {
1744 if (!verify_cb_cert(ctx, xi, xi != xs ? n+1 : n,
1745 X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY))
1747 } else if (X509_verify(xs, pkey) <= 0) {
1748 if (!verify_cb_cert(ctx, xs, n,
1749 X509_V_ERR_CERT_SIGNATURE_FAILURE))
1755 /* Calls verify callback as needed */
1756 if (!x509_check_cert_time(ctx, xs, n))
1760 * Signal success at this depth. However, the previous error (if any)
1763 ctx->current_issuer = xi;
1764 ctx->current_cert = xs;
1765 ctx->error_depth = n;
1766 if (!ctx->verify_cb(1, ctx))
1771 xs = sk_X509_value(ctx->chain, n);
1777 int X509_cmp_current_time(const ASN1_TIME *ctm)
1779 return X509_cmp_time(ctm, NULL);
1782 int X509_cmp_time(const ASN1_TIME *ctm, time_t *cmp_time)
1784 static const size_t utctime_length = sizeof("YYMMDDHHMMSSZ") - 1;
1785 static const size_t generalizedtime_length = sizeof("YYYYMMDDHHMMSSZ") - 1;
1786 ASN1_TIME *asn1_cmp_time = NULL;
1787 int i, day, sec, ret = 0;
1788 #ifdef CHARSET_EBCDIC
1789 const char upper_z = 0x5A;
1791 const char upper_z = 'Z';
1794 * Note that ASN.1 allows much more slack in the time format than RFC5280.
1795 * In RFC5280, the representation is fixed:
1796 * UTCTime: YYMMDDHHMMSSZ
1797 * GeneralizedTime: YYYYMMDDHHMMSSZ
1799 * We do NOT currently enforce the following RFC 5280 requirement:
1800 * "CAs conforming to this profile MUST always encode certificate
1801 * validity dates through the year 2049 as UTCTime; certificate validity
1802 * dates in 2050 or later MUST be encoded as GeneralizedTime."
1804 switch (ctm->type) {
1805 case V_ASN1_UTCTIME:
1806 if (ctm->length != (int)(utctime_length))
1809 case V_ASN1_GENERALIZEDTIME:
1810 if (ctm->length != (int)(generalizedtime_length))
1818 * Verify the format: the ASN.1 functions we use below allow a more
1819 * flexible format than what's mandated by RFC 5280.
1820 * Digit and date ranges will be verified in the conversion methods.
1822 for (i = 0; i < ctm->length - 1; i++) {
1823 if (!ascii_isdigit(ctm->data[i]))
1826 if (ctm->data[ctm->length - 1] != upper_z)
1830 * There is ASN1_UTCTIME_cmp_time_t but no
1831 * ASN1_GENERALIZEDTIME_cmp_time_t or ASN1_TIME_cmp_time_t,
1832 * so we go through ASN.1
1834 asn1_cmp_time = X509_time_adj(NULL, 0, cmp_time);
1835 if (asn1_cmp_time == NULL)
1837 if (!ASN1_TIME_diff(&day, &sec, ctm, asn1_cmp_time))
1841 * X509_cmp_time comparison is <=.
1842 * The return value 0 is reserved for errors.
1844 ret = (day >= 0 && sec >= 0) ? -1 : 1;
1847 ASN1_TIME_free(asn1_cmp_time);
1852 * Return 0 if time should not be checked or reference time is in range,
1853 * or else 1 if it is past the end, or -1 if it is before the start
1855 int X509_cmp_timeframe(const X509_VERIFY_PARAM *vpm,
1856 const ASN1_TIME *start, const ASN1_TIME *end)
1859 time_t *time = NULL;
1860 unsigned long flags = vpm == NULL ? 0 : X509_VERIFY_PARAM_get_flags(vpm);
1862 if ((flags & X509_V_FLAG_USE_CHECK_TIME) != 0) {
1863 ref_time = X509_VERIFY_PARAM_get_time(vpm);
1865 } else if ((flags & X509_V_FLAG_NO_CHECK_TIME) != 0) {
1866 return 0; /* this means ok */
1867 } /* else reference time is the current time */
1869 if (end != NULL && X509_cmp_time(end, time) < 0)
1871 if (start != NULL && X509_cmp_time(start, time) > 0)
1876 ASN1_TIME *X509_gmtime_adj(ASN1_TIME *s, long adj)
1878 return X509_time_adj(s, adj, NULL);
1881 ASN1_TIME *X509_time_adj(ASN1_TIME *s, long offset_sec, time_t *in_tm)
1883 return X509_time_adj_ex(s, 0, offset_sec, in_tm);
1886 ASN1_TIME *X509_time_adj_ex(ASN1_TIME *s,
1887 int offset_day, long offset_sec, time_t *in_tm)
1896 if (s && !(s->flags & ASN1_STRING_FLAG_MSTRING)) {
1897 if (s->type == V_ASN1_UTCTIME)
1898 return ASN1_UTCTIME_adj(s, t, offset_day, offset_sec);
1899 if (s->type == V_ASN1_GENERALIZEDTIME)
1900 return ASN1_GENERALIZEDTIME_adj(s, t, offset_day, offset_sec);
1902 return ASN1_TIME_adj(s, t, offset_day, offset_sec);
1905 int X509_get_pubkey_parameters(EVP_PKEY *pkey, STACK_OF(X509) *chain)
1907 EVP_PKEY *ktmp = NULL, *ktmp2;
1910 if ((pkey != NULL) && !EVP_PKEY_missing_parameters(pkey))
1913 for (i = 0; i < sk_X509_num(chain); i++) {
1914 ktmp = X509_get0_pubkey(sk_X509_value(chain, i));
1916 X509err(X509_F_X509_GET_PUBKEY_PARAMETERS,
1917 X509_R_UNABLE_TO_GET_CERTS_PUBLIC_KEY);
1920 if (!EVP_PKEY_missing_parameters(ktmp))
1924 X509err(X509_F_X509_GET_PUBKEY_PARAMETERS,
1925 X509_R_UNABLE_TO_FIND_PARAMETERS_IN_CHAIN);
1929 /* first, populate the other certs */
1930 for (j = i - 1; j >= 0; j--) {
1931 ktmp2 = X509_get0_pubkey(sk_X509_value(chain, j));
1932 EVP_PKEY_copy_parameters(ktmp2, ktmp);
1936 EVP_PKEY_copy_parameters(pkey, ktmp);
1940 /* Make a delta CRL as the diff between two full CRLs */
1942 X509_CRL *X509_CRL_diff(X509_CRL *base, X509_CRL *newer,
1943 EVP_PKEY *skey, const EVP_MD *md, unsigned int flags)
1945 X509_CRL *crl = NULL;
1947 STACK_OF(X509_REVOKED) *revs = NULL;
1948 /* CRLs can't be delta already */
1949 if (base->base_crl_number || newer->base_crl_number) {
1950 X509err(X509_F_X509_CRL_DIFF, X509_R_CRL_ALREADY_DELTA);
1953 /* Base and new CRL must have a CRL number */
1954 if (!base->crl_number || !newer->crl_number) {
1955 X509err(X509_F_X509_CRL_DIFF, X509_R_NO_CRL_NUMBER);
1958 /* Issuer names must match */
1959 if (X509_NAME_cmp(X509_CRL_get_issuer(base), X509_CRL_get_issuer(newer))) {
1960 X509err(X509_F_X509_CRL_DIFF, X509_R_ISSUER_MISMATCH);
1963 /* AKID and IDP must match */
1964 if (!crl_extension_match(base, newer, NID_authority_key_identifier)) {
1965 X509err(X509_F_X509_CRL_DIFF, X509_R_AKID_MISMATCH);
1968 if (!crl_extension_match(base, newer, NID_issuing_distribution_point)) {
1969 X509err(X509_F_X509_CRL_DIFF, X509_R_IDP_MISMATCH);
1972 /* Newer CRL number must exceed full CRL number */
1973 if (ASN1_INTEGER_cmp(newer->crl_number, base->crl_number) <= 0) {
1974 X509err(X509_F_X509_CRL_DIFF, X509_R_NEWER_CRL_NOT_NEWER);
1977 /* CRLs must verify */
1978 if (skey && (X509_CRL_verify(base, skey) <= 0 ||
1979 X509_CRL_verify(newer, skey) <= 0)) {
1980 X509err(X509_F_X509_CRL_DIFF, X509_R_CRL_VERIFY_FAILURE);
1983 /* Create new CRL */
1984 crl = X509_CRL_new();
1985 if (crl == NULL || !X509_CRL_set_version(crl, 1))
1987 /* Set issuer name */
1988 if (!X509_CRL_set_issuer_name(crl, X509_CRL_get_issuer(newer)))
1991 if (!X509_CRL_set1_lastUpdate(crl, X509_CRL_get0_lastUpdate(newer)))
1993 if (!X509_CRL_set1_nextUpdate(crl, X509_CRL_get0_nextUpdate(newer)))
1996 /* Set base CRL number: must be critical */
1998 if (!X509_CRL_add1_ext_i2d(crl, NID_delta_crl, base->crl_number, 1, 0))
2002 * Copy extensions across from newest CRL to delta: this will set CRL
2003 * number to correct value too.
2006 for (i = 0; i < X509_CRL_get_ext_count(newer); i++) {
2007 X509_EXTENSION *ext;
2008 ext = X509_CRL_get_ext(newer, i);
2009 if (!X509_CRL_add_ext(crl, ext, -1))
2013 /* Go through revoked entries, copying as needed */
2015 revs = X509_CRL_get_REVOKED(newer);
2017 for (i = 0; i < sk_X509_REVOKED_num(revs); i++) {
2018 X509_REVOKED *rvn, *rvtmp;
2019 rvn = sk_X509_REVOKED_value(revs, i);
2021 * Add only if not also in base. TODO: need something cleverer here
2022 * for some more complex CRLs covering multiple CAs.
2024 if (!X509_CRL_get0_by_serial(base, &rvtmp, &rvn->serialNumber)) {
2025 rvtmp = X509_REVOKED_dup(rvn);
2028 if (!X509_CRL_add0_revoked(crl, rvtmp)) {
2029 X509_REVOKED_free(rvtmp);
2034 /* TODO: optionally prune deleted entries */
2036 if (skey && md && !X509_CRL_sign(crl, skey, md))
2042 X509err(X509_F_X509_CRL_DIFF, ERR_R_MALLOC_FAILURE);
2047 int X509_STORE_CTX_set_ex_data(X509_STORE_CTX *ctx, int idx, void *data)
2049 return CRYPTO_set_ex_data(&ctx->ex_data, idx, data);
2052 void *X509_STORE_CTX_get_ex_data(const X509_STORE_CTX *ctx, int idx)
2054 return CRYPTO_get_ex_data(&ctx->ex_data, idx);
2057 int X509_STORE_CTX_get_error(const X509_STORE_CTX *ctx)
2062 void X509_STORE_CTX_set_error(X509_STORE_CTX *ctx, int err)
2067 int X509_STORE_CTX_get_error_depth(const X509_STORE_CTX *ctx)
2069 return ctx->error_depth;
2072 void X509_STORE_CTX_set_error_depth(X509_STORE_CTX *ctx, int depth)
2074 ctx->error_depth = depth;
2077 X509 *X509_STORE_CTX_get_current_cert(const X509_STORE_CTX *ctx)
2079 return ctx->current_cert;
2082 void X509_STORE_CTX_set_current_cert(X509_STORE_CTX *ctx, X509 *x)
2084 ctx->current_cert = x;
2087 STACK_OF(X509) *X509_STORE_CTX_get0_chain(const X509_STORE_CTX *ctx)
2092 STACK_OF(X509) *X509_STORE_CTX_get1_chain(const X509_STORE_CTX *ctx)
2096 return X509_chain_up_ref(ctx->chain);
2099 X509 *X509_STORE_CTX_get0_current_issuer(const X509_STORE_CTX *ctx)
2101 return ctx->current_issuer;
2104 X509_CRL *X509_STORE_CTX_get0_current_crl(const X509_STORE_CTX *ctx)
2106 return ctx->current_crl;
2109 X509_STORE_CTX *X509_STORE_CTX_get0_parent_ctx(const X509_STORE_CTX *ctx)
2114 void X509_STORE_CTX_set_cert(X509_STORE_CTX *ctx, X509 *x)
2119 void X509_STORE_CTX_set0_crls(X509_STORE_CTX *ctx, STACK_OF(X509_CRL) *sk)
2124 int X509_STORE_CTX_set_purpose(X509_STORE_CTX *ctx, int purpose)
2127 * XXX: Why isn't this function always used to set the associated trust?
2128 * Should there even be a VPM->trust field at all? Or should the trust
2129 * always be inferred from the purpose by X509_STORE_CTX_init().
2131 return X509_STORE_CTX_purpose_inherit(ctx, 0, purpose, 0);
2134 int X509_STORE_CTX_set_trust(X509_STORE_CTX *ctx, int trust)
2137 * XXX: See above, this function would only be needed when the default
2138 * trust for the purpose needs an override in a corner case.
2140 return X509_STORE_CTX_purpose_inherit(ctx, 0, 0, trust);
2144 * This function is used to set the X509_STORE_CTX purpose and trust values.
2145 * This is intended to be used when another structure has its own trust and
2146 * purpose values which (if set) will be inherited by the ctx. If they aren't
2147 * set then we will usually have a default purpose in mind which should then
2148 * be used to set the trust value. An example of this is SSL use: an SSL
2149 * structure will have its own purpose and trust settings which the
2150 * application can set: if they aren't set then we use the default of SSL
2154 int X509_STORE_CTX_purpose_inherit(X509_STORE_CTX *ctx, int def_purpose,
2155 int purpose, int trust)
2158 /* If purpose not set use default */
2160 purpose = def_purpose;
2161 /* If we have a purpose then check it is valid */
2164 idx = X509_PURPOSE_get_by_id(purpose);
2166 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2167 X509_R_UNKNOWN_PURPOSE_ID);
2170 ptmp = X509_PURPOSE_get0(idx);
2171 if (ptmp->trust == X509_TRUST_DEFAULT) {
2172 idx = X509_PURPOSE_get_by_id(def_purpose);
2174 * XXX: In the two callers above def_purpose is always 0, which is
2175 * not a known value, so idx will always be -1. How is the
2176 * X509_TRUST_DEFAULT case actually supposed to be handled?
2179 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2180 X509_R_UNKNOWN_PURPOSE_ID);
2183 ptmp = X509_PURPOSE_get0(idx);
2185 /* If trust not set then get from purpose default */
2187 trust = ptmp->trust;
2190 idx = X509_TRUST_get_by_id(trust);
2192 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2193 X509_R_UNKNOWN_TRUST_ID);
2198 if (purpose && !ctx->param->purpose)
2199 ctx->param->purpose = purpose;
2200 if (trust && !ctx->param->trust)
2201 ctx->param->trust = trust;
2205 X509_STORE_CTX *X509_STORE_CTX_new(void)
2207 X509_STORE_CTX *ctx = OPENSSL_zalloc(sizeof(*ctx));
2210 X509err(X509_F_X509_STORE_CTX_NEW, ERR_R_MALLOC_FAILURE);
2216 void X509_STORE_CTX_free(X509_STORE_CTX *ctx)
2221 X509_STORE_CTX_cleanup(ctx);
2225 int X509_STORE_CTX_init(X509_STORE_CTX *ctx, X509_STORE *store, X509 *x509,
2226 STACK_OF(X509) *chain)
2232 ctx->untrusted = chain;
2234 ctx->num_untrusted = 0;
2235 ctx->other_ctx = NULL;
2239 ctx->explicit_policy = 0;
2240 ctx->error_depth = 0;
2241 ctx->current_cert = NULL;
2242 ctx->current_issuer = NULL;
2243 ctx->current_crl = NULL;
2244 ctx->current_crl_score = 0;
2245 ctx->current_reasons = 0;
2249 ctx->bare_ta_signed = 0;
2250 /* Zero ex_data to make sure we're cleanup-safe */
2251 memset(&ctx->ex_data, 0, sizeof(ctx->ex_data));
2253 /* store->cleanup is always 0 in OpenSSL, if set must be idempotent */
2255 ctx->cleanup = store->cleanup;
2259 if (store && store->check_issued)
2260 ctx->check_issued = store->check_issued;
2262 ctx->check_issued = check_issued;
2264 if (store && store->get_issuer)
2265 ctx->get_issuer = store->get_issuer;
2267 ctx->get_issuer = X509_STORE_CTX_get1_issuer;
2269 if (store && store->verify_cb)
2270 ctx->verify_cb = store->verify_cb;
2272 ctx->verify_cb = null_callback;
2274 if (store && store->verify)
2275 ctx->verify = store->verify;
2277 ctx->verify = internal_verify;
2279 if (store && store->check_revocation)
2280 ctx->check_revocation = store->check_revocation;
2282 ctx->check_revocation = check_revocation;
2284 if (store && store->get_crl)
2285 ctx->get_crl = store->get_crl;
2287 ctx->get_crl = NULL;
2289 if (store && store->check_crl)
2290 ctx->check_crl = store->check_crl;
2292 ctx->check_crl = check_crl;
2294 if (store && store->cert_crl)
2295 ctx->cert_crl = store->cert_crl;
2297 ctx->cert_crl = cert_crl;
2299 if (store && store->check_policy)
2300 ctx->check_policy = store->check_policy;
2302 ctx->check_policy = check_policy;
2304 if (store && store->lookup_certs)
2305 ctx->lookup_certs = store->lookup_certs;
2307 ctx->lookup_certs = X509_STORE_CTX_get1_certs;
2309 if (store && store->lookup_crls)
2310 ctx->lookup_crls = store->lookup_crls;
2312 ctx->lookup_crls = X509_STORE_CTX_get1_crls;
2314 ctx->param = X509_VERIFY_PARAM_new();
2315 if (ctx->param == NULL) {
2316 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2321 * Inherit callbacks and flags from X509_STORE if not set use defaults.
2324 ret = X509_VERIFY_PARAM_inherit(ctx->param, store->param);
2326 ctx->param->inh_flags |= X509_VP_FLAG_DEFAULT | X509_VP_FLAG_ONCE;
2329 ret = X509_VERIFY_PARAM_inherit(ctx->param,
2330 X509_VERIFY_PARAM_lookup("default"));
2333 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2338 * XXX: For now, continue to inherit trust from VPM, but infer from the
2339 * purpose if this still yields the default value.
2341 if (ctx->param->trust == X509_TRUST_DEFAULT) {
2342 int idx = X509_PURPOSE_get_by_id(ctx->param->purpose);
2343 X509_PURPOSE *xp = X509_PURPOSE_get0(idx);
2346 ctx->param->trust = X509_PURPOSE_get_trust(xp);
2349 if (CRYPTO_new_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx,
2352 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2356 * On error clean up allocated storage, if the store context was not
2357 * allocated with X509_STORE_CTX_new() this is our last chance to do so.
2359 X509_STORE_CTX_cleanup(ctx);
2364 * Set alternative lookup method: just a STACK of trusted certificates. This
2365 * avoids X509_STORE nastiness where it isn't needed.
2367 void X509_STORE_CTX_set0_trusted_stack(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2369 ctx->other_ctx = sk;
2370 ctx->get_issuer = get_issuer_sk;
2371 ctx->lookup_certs = lookup_certs_sk;
2374 void X509_STORE_CTX_cleanup(X509_STORE_CTX *ctx)
2377 * We need to be idempotent because, unfortunately, free() also calls
2378 * cleanup(), so the natural call sequence new(), init(), cleanup(), free()
2379 * calls cleanup() for the same object twice! Thus we must zero the
2380 * pointers below after they're freed!
2382 /* Seems to always be 0 in OpenSSL, do this at most once. */
2383 if (ctx->cleanup != NULL) {
2385 ctx->cleanup = NULL;
2387 if (ctx->param != NULL) {
2388 if (ctx->parent == NULL)
2389 X509_VERIFY_PARAM_free(ctx->param);
2392 X509_policy_tree_free(ctx->tree);
2394 sk_X509_pop_free(ctx->chain, X509_free);
2396 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx, &(ctx->ex_data));
2397 memset(&ctx->ex_data, 0, sizeof(ctx->ex_data));
2400 void X509_STORE_CTX_set_depth(X509_STORE_CTX *ctx, int depth)
2402 X509_VERIFY_PARAM_set_depth(ctx->param, depth);
2405 void X509_STORE_CTX_set_flags(X509_STORE_CTX *ctx, unsigned long flags)
2407 X509_VERIFY_PARAM_set_flags(ctx->param, flags);
2410 void X509_STORE_CTX_set_time(X509_STORE_CTX *ctx, unsigned long flags,
2413 X509_VERIFY_PARAM_set_time(ctx->param, t);
2416 X509 *X509_STORE_CTX_get0_cert(const X509_STORE_CTX *ctx)
2421 STACK_OF(X509) *X509_STORE_CTX_get0_untrusted(const X509_STORE_CTX *ctx)
2423 return ctx->untrusted;
2426 void X509_STORE_CTX_set0_untrusted(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2428 ctx->untrusted = sk;
2431 void X509_STORE_CTX_set0_verified_chain(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2433 sk_X509_pop_free(ctx->chain, X509_free);
2437 void X509_STORE_CTX_set_verify_cb(X509_STORE_CTX *ctx,
2438 X509_STORE_CTX_verify_cb verify_cb)
2440 ctx->verify_cb = verify_cb;
2443 X509_STORE_CTX_verify_cb X509_STORE_CTX_get_verify_cb(const X509_STORE_CTX *ctx)
2445 return ctx->verify_cb;
2448 void X509_STORE_CTX_set_verify(X509_STORE_CTX *ctx,
2449 X509_STORE_CTX_verify_fn verify)
2451 ctx->verify = verify;
2454 X509_STORE_CTX_verify_fn X509_STORE_CTX_get_verify(const X509_STORE_CTX *ctx)
2459 X509_STORE_CTX_get_issuer_fn X509_STORE_CTX_get_get_issuer(const X509_STORE_CTX *ctx)
2461 return ctx->get_issuer;
2464 X509_STORE_CTX_check_issued_fn
2465 X509_STORE_CTX_get_check_issued(const X509_STORE_CTX *ctx)
2467 return ctx->check_issued;
2470 X509_STORE_CTX_check_revocation_fn
2471 X509_STORE_CTX_get_check_revocation(const X509_STORE_CTX *ctx)
2473 return ctx->check_revocation;
2476 X509_STORE_CTX_get_crl_fn X509_STORE_CTX_get_get_crl(const X509_STORE_CTX *ctx)
2478 return ctx->get_crl;
2481 X509_STORE_CTX_check_crl_fn X509_STORE_CTX_get_check_crl(const X509_STORE_CTX *ctx)
2483 return ctx->check_crl;
2486 X509_STORE_CTX_cert_crl_fn X509_STORE_CTX_get_cert_crl(const X509_STORE_CTX *ctx)
2488 return ctx->cert_crl;
2491 X509_STORE_CTX_check_policy_fn
2492 X509_STORE_CTX_get_check_policy(const X509_STORE_CTX *ctx)
2494 return ctx->check_policy;
2497 X509_STORE_CTX_lookup_certs_fn
2498 X509_STORE_CTX_get_lookup_certs(const X509_STORE_CTX *ctx)
2500 return ctx->lookup_certs;
2503 X509_STORE_CTX_lookup_crls_fn
2504 X509_STORE_CTX_get_lookup_crls(const X509_STORE_CTX *ctx)
2506 return ctx->lookup_crls;
2509 X509_STORE_CTX_cleanup_fn X509_STORE_CTX_get_cleanup(const X509_STORE_CTX *ctx)
2511 return ctx->cleanup;
2514 X509_POLICY_TREE *X509_STORE_CTX_get0_policy_tree(const X509_STORE_CTX *ctx)
2519 int X509_STORE_CTX_get_explicit_policy(const X509_STORE_CTX *ctx)
2521 return ctx->explicit_policy;
2524 int X509_STORE_CTX_get_num_untrusted(const X509_STORE_CTX *ctx)
2526 return ctx->num_untrusted;
2529 int X509_STORE_CTX_set_default(X509_STORE_CTX *ctx, const char *name)
2531 const X509_VERIFY_PARAM *param;
2533 param = X509_VERIFY_PARAM_lookup(name);
2536 return X509_VERIFY_PARAM_inherit(ctx->param, param);
2539 X509_VERIFY_PARAM *X509_STORE_CTX_get0_param(const X509_STORE_CTX *ctx)
2544 void X509_STORE_CTX_set0_param(X509_STORE_CTX *ctx, X509_VERIFY_PARAM *param)
2546 X509_VERIFY_PARAM_free(ctx->param);
2550 void X509_STORE_CTX_set0_dane(X509_STORE_CTX *ctx, SSL_DANE *dane)
2555 static unsigned char *dane_i2d(
2558 unsigned int *i2dlen)
2560 unsigned char *buf = NULL;
2564 * Extract ASN.1 DER form of certificate or public key.
2567 case DANETLS_SELECTOR_CERT:
2568 len = i2d_X509(cert, &buf);
2570 case DANETLS_SELECTOR_SPKI:
2571 len = i2d_X509_PUBKEY(X509_get_X509_PUBKEY(cert), &buf);
2574 X509err(X509_F_DANE_I2D, X509_R_BAD_SELECTOR);
2578 if (len < 0 || buf == NULL) {
2579 X509err(X509_F_DANE_I2D, ERR_R_MALLOC_FAILURE);
2583 *i2dlen = (unsigned int)len;
2587 #define DANETLS_NONE 256 /* impossible uint8_t */
2589 static int dane_match(X509_STORE_CTX *ctx, X509 *cert, int depth)
2591 SSL_DANE *dane = ctx->dane;
2592 unsigned usage = DANETLS_NONE;
2593 unsigned selector = DANETLS_NONE;
2594 unsigned ordinal = DANETLS_NONE;
2595 unsigned mtype = DANETLS_NONE;
2596 unsigned char *i2dbuf = NULL;
2597 unsigned int i2dlen = 0;
2598 unsigned char mdbuf[EVP_MAX_MD_SIZE];
2599 unsigned char *cmpbuf = NULL;
2600 unsigned int cmplen = 0;
2604 danetls_record *t = NULL;
2607 mask = (depth == 0) ? DANETLS_EE_MASK : DANETLS_TA_MASK;
2610 * The trust store is not applicable with DANE-TA(2)
2612 if (depth >= ctx->num_untrusted)
2613 mask &= DANETLS_PKIX_MASK;
2616 * If we've previously matched a PKIX-?? record, no need to test any
2617 * further PKIX-?? records, it remains to just build the PKIX chain.
2618 * Had the match been a DANE-?? record, we'd be done already.
2620 if (dane->mdpth >= 0)
2621 mask &= ~DANETLS_PKIX_MASK;
2624 * https://tools.ietf.org/html/rfc7671#section-5.1
2625 * https://tools.ietf.org/html/rfc7671#section-5.2
2626 * https://tools.ietf.org/html/rfc7671#section-5.3
2627 * https://tools.ietf.org/html/rfc7671#section-5.4
2629 * We handle DANE-EE(3) records first as they require no chain building
2630 * and no expiration or hostname checks. We also process digests with
2631 * higher ordinals first and ignore lower priorities except Full(0) which
2632 * is always processed (last). If none match, we then process PKIX-EE(1).
2634 * NOTE: This relies on DANE usages sorting before the corresponding PKIX
2635 * usages in SSL_dane_tlsa_add(), and also on descending sorting of digest
2636 * priorities. See twin comment in ssl/ssl_lib.c.
2638 * We expect that most TLSA RRsets will have just a single usage, so we
2639 * don't go out of our way to cache multiple selector-specific i2d buffers
2640 * across usages, but if the selector happens to remain the same as switch
2641 * usages, that's OK. Thus, a set of "3 1 1", "3 0 1", "1 1 1", "1 0 1",
2642 * records would result in us generating each of the certificate and public
2643 * key DER forms twice, but more typically we'd just see multiple "3 1 1"
2644 * or multiple "3 0 1" records.
2646 * As soon as we find a match at any given depth, we stop, because either
2647 * we've matched a DANE-?? record and the peer is authenticated, or, after
2648 * exhausting all DANE-?? records, we've matched a PKIX-?? record, which is
2649 * sufficient for DANE, and what remains to do is ordinary PKIX validation.
2651 recnum = (dane->umask & mask) ? sk_danetls_record_num(dane->trecs) : 0;
2652 for (i = 0; matched == 0 && i < recnum; ++i) {
2653 t = sk_danetls_record_value(dane->trecs, i);
2654 if ((DANETLS_USAGE_BIT(t->usage) & mask) == 0)
2656 if (t->usage != usage) {
2659 /* Reset digest agility for each usage/selector pair */
2660 mtype = DANETLS_NONE;
2661 ordinal = dane->dctx->mdord[t->mtype];
2663 if (t->selector != selector) {
2664 selector = t->selector;
2666 /* Update per-selector state */
2667 OPENSSL_free(i2dbuf);
2668 i2dbuf = dane_i2d(cert, selector, &i2dlen);
2672 /* Reset digest agility for each usage/selector pair */
2673 mtype = DANETLS_NONE;
2674 ordinal = dane->dctx->mdord[t->mtype];
2675 } else if (t->mtype != DANETLS_MATCHING_FULL) {
2679 * <https://tools.ietf.org/html/rfc7671#section-9>
2681 * For a fixed selector, after processing all records with the
2682 * highest mtype ordinal, ignore all mtypes with lower ordinals
2683 * other than "Full".
2685 if (dane->dctx->mdord[t->mtype] < ordinal)
2690 * Each time we hit a (new selector or) mtype, re-compute the relevant
2691 * digest, more complex caching is not worth the code space.
2693 if (t->mtype != mtype) {
2694 const EVP_MD *md = dane->dctx->mdevp[mtype = t->mtype];
2700 if (!EVP_Digest(i2dbuf, i2dlen, cmpbuf, &cmplen, md, 0)) {
2708 * Squirrel away the certificate and depth if we have a match. Any
2709 * DANE match is dispositive, but with PKIX we still need to build a
2712 if (cmplen == t->dlen &&
2713 memcmp(cmpbuf, t->data, cmplen) == 0) {
2714 if (DANETLS_USAGE_BIT(usage) & DANETLS_DANE_MASK)
2716 if (matched || dane->mdpth < 0) {
2717 dane->mdpth = depth;
2719 OPENSSL_free(dane->mcert);
2727 /* Clear the one-element DER cache */
2728 OPENSSL_free(i2dbuf);
2732 static int check_dane_issuer(X509_STORE_CTX *ctx, int depth)
2734 SSL_DANE *dane = ctx->dane;
2738 if (!DANETLS_HAS_TA(dane) || depth == 0)
2739 return X509_TRUST_UNTRUSTED;
2742 * Record any DANE trust-anchor matches, for the first depth to test, if
2743 * there's one at that depth. (This'll be false for length 1 chains looking
2744 * for an exact match for the leaf certificate).
2746 cert = sk_X509_value(ctx->chain, depth);
2747 if (cert != NULL && (matched = dane_match(ctx, cert, depth)) < 0)
2748 return X509_TRUST_REJECTED;
2750 ctx->num_untrusted = depth - 1;
2751 return X509_TRUST_TRUSTED;
2754 return X509_TRUST_UNTRUSTED;
2757 static int check_dane_pkeys(X509_STORE_CTX *ctx)
2759 SSL_DANE *dane = ctx->dane;
2761 int num = ctx->num_untrusted;
2762 X509 *cert = sk_X509_value(ctx->chain, num - 1);
2763 int recnum = sk_danetls_record_num(dane->trecs);
2766 for (i = 0; i < recnum; ++i) {
2767 t = sk_danetls_record_value(dane->trecs, i);
2768 if (t->usage != DANETLS_USAGE_DANE_TA ||
2769 t->selector != DANETLS_SELECTOR_SPKI ||
2770 t->mtype != DANETLS_MATCHING_FULL ||
2771 X509_verify(cert, t->spki) <= 0)
2774 /* Clear any PKIX-?? matches that failed to extend to a full chain */
2775 X509_free(dane->mcert);
2778 /* Record match via a bare TA public key */
2779 ctx->bare_ta_signed = 1;
2780 dane->mdpth = num - 1;
2783 /* Prune any excess chain certificates */
2784 num = sk_X509_num(ctx->chain);
2785 for (; num > ctx->num_untrusted; --num)
2786 X509_free(sk_X509_pop(ctx->chain));
2788 return X509_TRUST_TRUSTED;
2791 return X509_TRUST_UNTRUSTED;
2794 static void dane_reset(SSL_DANE *dane)
2797 * Reset state to verify another chain, or clear after failure.
2799 X509_free(dane->mcert);
2806 static int check_leaf_suiteb(X509_STORE_CTX *ctx, X509 *cert)
2808 int err = X509_chain_check_suiteb(NULL, cert, NULL, ctx->param->flags);
2810 if (err == X509_V_OK)
2812 return verify_cb_cert(ctx, cert, 0, err);
2815 static int dane_verify(X509_STORE_CTX *ctx)
2817 X509 *cert = ctx->cert;
2818 SSL_DANE *dane = ctx->dane;
2825 * When testing the leaf certificate, if we match a DANE-EE(3) record,
2826 * dane_match() returns 1 and we're done. If however we match a PKIX-EE(1)
2827 * record, the match depth and matching TLSA record are recorded, but the
2828 * return value is 0, because we still need to find a PKIX trust-anchor.
2829 * Therefore, when DANE authentication is enabled (required), we're done
2831 * + matched < 0, internal error.
2832 * + matched == 1, we matched a DANE-EE(3) record
2833 * + matched == 0, mdepth < 0 (no PKIX-EE match) and there are no
2834 * DANE-TA(2) or PKIX-TA(0) to test.
2836 matched = dane_match(ctx, ctx->cert, 0);
2837 done = matched != 0 || (!DANETLS_HAS_TA(dane) && dane->mdpth < 0);
2840 X509_get_pubkey_parameters(NULL, ctx->chain);
2843 /* Callback invoked as needed */
2844 if (!check_leaf_suiteb(ctx, cert))
2846 /* Callback invoked as needed */
2847 if ((dane->flags & DANE_FLAG_NO_DANE_EE_NAMECHECKS) == 0 &&
2850 /* Bypass internal_verify(), issue depth 0 success callback */
2851 ctx->error_depth = 0;
2852 ctx->current_cert = cert;
2853 return ctx->verify_cb(1, ctx);
2857 ctx->error_depth = 0;
2858 ctx->current_cert = cert;
2859 ctx->error = X509_V_ERR_OUT_OF_MEM;
2864 /* Fail early, TA-based success is not possible */
2865 if (!check_leaf_suiteb(ctx, cert))
2867 return verify_cb_cert(ctx, cert, 0, X509_V_ERR_DANE_NO_MATCH);
2871 * Chain verification for usages 0/1/2. TLSA record matching of depth > 0
2872 * certificates happens in-line with building the rest of the chain.
2874 return verify_chain(ctx);
2877 /* Get issuer, without duplicate suppression */
2878 static int get_issuer(X509 **issuer, X509_STORE_CTX *ctx, X509 *cert)
2880 STACK_OF(X509) *saved_chain = ctx->chain;
2884 ok = ctx->get_issuer(issuer, ctx, cert);
2885 ctx->chain = saved_chain;
2890 static int build_chain(X509_STORE_CTX *ctx)
2892 SSL_DANE *dane = ctx->dane;
2893 int num = sk_X509_num(ctx->chain);
2894 X509 *cert = sk_X509_value(ctx->chain, num - 1);
2895 int ss = cert_self_signed(cert);
2896 STACK_OF(X509) *sktmp = NULL;
2897 unsigned int search;
2898 int may_trusted = 0;
2899 int may_alternate = 0;
2900 int trust = X509_TRUST_UNTRUSTED;
2901 int alt_untrusted = 0;
2906 /* Our chain starts with a single untrusted element. */
2907 if (!ossl_assert(num == 1 && ctx->num_untrusted == num)) {
2908 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
2909 ctx->error = X509_V_ERR_UNSPECIFIED;
2913 #define S_DOUNTRUSTED (1 << 0) /* Search untrusted chain */
2914 #define S_DOTRUSTED (1 << 1) /* Search trusted store */
2915 #define S_DOALTERNATE (1 << 2) /* Retry with pruned alternate chain */
2917 * Set up search policy, untrusted if possible, trusted-first if enabled.
2918 * If we're doing DANE and not doing PKIX-TA/PKIX-EE, we never look in the
2919 * trust_store, otherwise we might look there first. If not trusted-first,
2920 * and alternate chains are not disabled, try building an alternate chain
2921 * if no luck with untrusted first.
2923 search = (ctx->untrusted != NULL) ? S_DOUNTRUSTED : 0;
2924 if (DANETLS_HAS_PKIX(dane) || !DANETLS_HAS_DANE(dane)) {
2925 if (search == 0 || ctx->param->flags & X509_V_FLAG_TRUSTED_FIRST)
2926 search |= S_DOTRUSTED;
2927 else if (!(ctx->param->flags & X509_V_FLAG_NO_ALT_CHAINS))
2933 * Shallow-copy the stack of untrusted certificates (with TLS, this is
2934 * typically the content of the peer's certificate message) so can make
2935 * multiple passes over it, while free to remove elements as we go.
2937 if (ctx->untrusted && (sktmp = sk_X509_dup(ctx->untrusted)) == NULL) {
2938 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2939 ctx->error = X509_V_ERR_OUT_OF_MEM;
2944 * If we got any "DANE-TA(2) Cert(0) Full(0)" trust-anchors from DNS, add
2945 * them to our working copy of the untrusted certificate stack. Since the
2946 * caller of X509_STORE_CTX_init() may have provided only a leaf cert with
2947 * no corresponding stack of untrusted certificates, we may need to create
2948 * an empty stack first. [ At present only the ssl library provides DANE
2949 * support, and ssl_verify_cert_chain() always provides a non-null stack
2950 * containing at least the leaf certificate, but we must be prepared for
2953 if (DANETLS_ENABLED(dane) && dane->certs != NULL) {
2954 if (sktmp == NULL && (sktmp = sk_X509_new_null()) == NULL) {
2955 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2956 ctx->error = X509_V_ERR_OUT_OF_MEM;
2959 for (i = 0; i < sk_X509_num(dane->certs); ++i) {
2960 if (!sk_X509_push(sktmp, sk_X509_value(dane->certs, i))) {
2961 sk_X509_free(sktmp);
2962 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2963 ctx->error = X509_V_ERR_OUT_OF_MEM;
2970 * Still absurdly large, but arithmetically safe, a lower hard upper bound
2971 * might be reasonable.
2973 if (ctx->param->depth > INT_MAX/2)
2974 ctx->param->depth = INT_MAX/2;
2977 * Try to Extend the chain until we reach an ultimately trusted issuer.
2978 * Build chains up to one longer the limit, later fail if we hit the limit,
2979 * with an X509_V_ERR_CERT_CHAIN_TOO_LONG error code.
2981 depth = ctx->param->depth + 1;
2983 while (search != 0) {
2988 * Look in the trust store if enabled for first lookup, or we've run
2989 * out of untrusted issuers and search here is not disabled. When we
2990 * reach the depth limit, we stop extending the chain, if by that point
2991 * we've not found a trust-anchor, any trusted chain would be too long.
2993 * The error reported to the application verify callback is at the
2994 * maximal valid depth with the current certificate equal to the last
2995 * not ultimately-trusted issuer. For example, with verify_depth = 0,
2996 * the callback will report errors at depth=1 when the immediate issuer
2997 * of the leaf certificate is not a trust anchor. No attempt will be
2998 * made to locate an issuer for that certificate, since such a chain
2999 * would be a-priori too long.
3001 if ((search & S_DOTRUSTED) != 0) {
3002 i = num = sk_X509_num(ctx->chain);
3003 if ((search & S_DOALTERNATE) != 0) {
3005 * As high up the chain as we can, look for an alternative
3006 * trusted issuer of an untrusted certificate that currently
3007 * has an untrusted issuer. We use the alt_untrusted variable
3008 * to track how far up the chain we find the first match. It
3009 * is only if and when we find a match, that we prune the chain
3010 * and reset ctx->num_untrusted to the reduced count of
3011 * untrusted certificates. While we're searching for such a
3012 * match (which may never be found), it is neither safe nor
3013 * wise to preemptively modify either the chain or
3014 * ctx->num_untrusted.
3016 * Note, like ctx->num_untrusted, alt_untrusted is a count of
3017 * untrusted certificates, not a "depth".
3021 x = sk_X509_value(ctx->chain, i-1);
3023 ok = (depth < num) ? 0 : get_issuer(&xtmp, ctx, x);
3026 trust = X509_TRUST_REJECTED;
3027 ctx->error = X509_V_ERR_STORE_LOOKUP;
3034 * Alternative trusted issuer for a mid-chain untrusted cert?
3035 * Pop the untrusted cert's successors and retry. We might now
3036 * be able to complete a valid chain via the trust store. Note
3037 * that despite the current trust-store match we might still
3038 * fail complete the chain to a suitable trust-anchor, in which
3039 * case we may prune some more untrusted certificates and try
3040 * again. Thus the S_DOALTERNATE bit may yet be turned on
3041 * again with an even shorter untrusted chain!
3043 * If in the process we threw away our matching PKIX-TA trust
3044 * anchor, reset DANE trust. We might find a suitable trusted
3045 * certificate among the ones from the trust store.
3047 if ((search & S_DOALTERNATE) != 0) {
3048 if (!ossl_assert(num > i && i > 0 && ss == 0)) {
3049 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
3051 trust = X509_TRUST_REJECTED;
3052 ctx->error = X509_V_ERR_UNSPECIFIED;
3056 search &= ~S_DOALTERNATE;
3057 for (; num > i; --num)
3058 X509_free(sk_X509_pop(ctx->chain));
3059 ctx->num_untrusted = num;
3061 if (DANETLS_ENABLED(dane) &&
3062 dane->mdpth >= ctx->num_untrusted) {
3064 X509_free(dane->mcert);
3067 if (DANETLS_ENABLED(dane) &&
3068 dane->pdpth >= ctx->num_untrusted)
3073 * Self-signed untrusted certificates get replaced by their
3074 * trusted matching issuer. Otherwise, grow the chain.
3077 if (!sk_X509_push(ctx->chain, x = xtmp)) {
3079 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
3080 trust = X509_TRUST_REJECTED;
3081 ctx->error = X509_V_ERR_OUT_OF_MEM;
3085 ss = cert_self_signed(x);
3086 } else if (num == ctx->num_untrusted) {
3088 * We have a self-signed certificate that has the same
3089 * subject name (and perhaps keyid and/or serial number) as
3090 * a trust-anchor. We must have an exact match to avoid
3091 * possible impersonation via key substitution etc.
3093 if (X509_cmp(x, xtmp) != 0) {
3094 /* Self-signed untrusted mimic. */
3099 ctx->num_untrusted = --num;
3100 (void) sk_X509_set(ctx->chain, num, x = xtmp);
3105 * We've added a new trusted certificate to the chain, recheck
3106 * trust. If not done, and not self-signed look deeper.
3107 * Whether or not we're doing "trusted first", we no longer
3108 * look for untrusted certificates from the peer's chain.
3110 * At this point ctx->num_trusted and num must reflect the
3111 * correct number of untrusted certificates, since the DANE
3112 * logic in check_trust() depends on distinguishing CAs from
3113 * "the wire" from CAs from the trust store. In particular, the
3114 * certificate at depth "num" should be the new trusted
3115 * certificate with ctx->num_untrusted <= num.
3118 if (!ossl_assert(ctx->num_untrusted <= num)) {
3119 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
3120 trust = X509_TRUST_REJECTED;
3121 ctx->error = X509_V_ERR_UNSPECIFIED;
3125 search &= ~S_DOUNTRUSTED;
3126 switch (trust = check_trust(ctx, num)) {
3127 case X509_TRUST_TRUSTED:
3128 case X509_TRUST_REJECTED:
3138 * No dispositive decision, and either self-signed or no match, if
3139 * we were doing untrusted-first, and alt-chains are not disabled,
3140 * do that, by repeatedly losing one untrusted element at a time,
3141 * and trying to extend the shorted chain.
3143 if ((search & S_DOUNTRUSTED) == 0) {
3144 /* Continue search for a trusted issuer of a shorter chain? */
3145 if ((search & S_DOALTERNATE) != 0 && --alt_untrusted > 0)
3147 /* Still no luck and no fallbacks left? */
3148 if (!may_alternate || (search & S_DOALTERNATE) != 0 ||
3149 ctx->num_untrusted < 2)
3151 /* Search for a trusted issuer of a shorter chain */
3152 search |= S_DOALTERNATE;
3153 alt_untrusted = ctx->num_untrusted - 1;
3159 * Extend chain with peer-provided certificates
3161 if ((search & S_DOUNTRUSTED) != 0) {
3162 num = sk_X509_num(ctx->chain);
3163 if (!ossl_assert(num == ctx->num_untrusted)) {
3164 X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR);
3165 trust = X509_TRUST_REJECTED;
3166 ctx->error = X509_V_ERR_UNSPECIFIED;
3170 x = sk_X509_value(ctx->chain, num-1);
3173 * Once we run out of untrusted issuers, we stop looking for more
3174 * and start looking only in the trust store if enabled.
3176 xtmp = (ss || depth < num) ? NULL : find_issuer(ctx, sktmp, x);
3178 search &= ~S_DOUNTRUSTED;
3180 search |= S_DOTRUSTED;
3184 /* Drop this issuer from future consideration */
3185 (void) sk_X509_delete_ptr(sktmp, xtmp);
3187 if (!sk_X509_push(ctx->chain, xtmp)) {
3188 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
3189 trust = X509_TRUST_REJECTED;
3190 ctx->error = X509_V_ERR_OUT_OF_MEM;
3195 X509_up_ref(x = xtmp);
3196 ++ctx->num_untrusted;
3197 ss = cert_self_signed(xtmp);
3200 * Check for DANE-TA trust of the topmost untrusted certificate.
3202 switch (trust = check_dane_issuer(ctx, ctx->num_untrusted - 1)) {
3203 case X509_TRUST_TRUSTED:
3204 case X509_TRUST_REJECTED:
3210 sk_X509_free(sktmp);
3213 * Last chance to make a trusted chain, either bare DANE-TA public-key
3214 * signers, or else direct leaf PKIX trust.
3216 num = sk_X509_num(ctx->chain);
3218 if (trust == X509_TRUST_UNTRUSTED && DANETLS_HAS_DANE_TA(dane))
3219 trust = check_dane_pkeys(ctx);
3220 if (trust == X509_TRUST_UNTRUSTED && num == ctx->num_untrusted)
3221 trust = check_trust(ctx, num);
3225 case X509_TRUST_TRUSTED:
3227 case X509_TRUST_REJECTED:
3228 /* Callback already issued */
3230 case X509_TRUST_UNTRUSTED:
3232 num = sk_X509_num(ctx->chain);
3234 return verify_cb_cert(ctx, NULL, num-1,
3235 X509_V_ERR_CERT_CHAIN_TOO_LONG);
3236 if (DANETLS_ENABLED(dane) &&
3237 (!DANETLS_HAS_PKIX(dane) || dane->pdpth >= 0))
3238 return verify_cb_cert(ctx, NULL, num-1, X509_V_ERR_DANE_NO_MATCH);
3239 if (ss && sk_X509_num(ctx->chain) == 1)
3240 return verify_cb_cert(ctx, NULL, num-1,
3241 X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT);
3243 return verify_cb_cert(ctx, NULL, num-1,
3244 X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN);
3245 if (ctx->num_untrusted < num)
3246 return verify_cb_cert(ctx, NULL, num-1,
3247 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT);
3248 return verify_cb_cert(ctx, NULL, num-1,
3249 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY);
3253 static const int minbits_table[] = { 80, 112, 128, 192, 256 };
3254 static const int NUM_AUTH_LEVELS = OSSL_NELEM(minbits_table);
3257 * Check whether the public key of ``cert`` meets the security level of
3260 * Returns 1 on success, 0 otherwise.
3262 static int check_key_level(X509_STORE_CTX *ctx, X509 *cert)
3264 EVP_PKEY *pkey = X509_get0_pubkey(cert);
3265 int level = ctx->param->auth_level;
3268 * At security level zero, return without checking for a supported public
3269 * key type. Some engines support key types not understood outside the
3270 * engine, and we only need to understand the key when enforcing a security
3276 /* Unsupported or malformed keys are not secure */
3280 if (level > NUM_AUTH_LEVELS)
3281 level = NUM_AUTH_LEVELS;
3283 return EVP_PKEY_security_bits(pkey) >= minbits_table[level - 1];
3287 * Check whether the signature digest algorithm of ``cert`` meets the security
3288 * level of ``ctx``. Should not be checked for trust anchors (whether
3289 * self-signed or otherwise).
3291 * Returns 1 on success, 0 otherwise.
3293 static int check_sig_level(X509_STORE_CTX *ctx, X509 *cert)
3296 int level = ctx->param->auth_level;
3300 if (level > NUM_AUTH_LEVELS)
3301 level = NUM_AUTH_LEVELS;
3303 if (!X509_get_signature_info(cert, NULL, NULL, &secbits, NULL))
3306 return secbits >= minbits_table[level - 1];