2 * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the OpenSSL license (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
15 #include "internal/cryptlib.h"
16 #include <openssl/crypto.h>
17 #include <openssl/lhash.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 <internal/x509_int.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_name_constraints(ctx)) == 0 ||
220 (ok = check_id(ctx)) == 0 || 1)
221 X509_get_pubkey_parameters(NULL, ctx->chain);
222 if (ok == 0 || (ok = ctx->check_revocation(ctx)) == 0)
225 err = X509_chain_check_suiteb(&ctx->error_depth, NULL, ctx->chain,
227 if (err != X509_V_OK) {
228 if ((ok = verify_cb_cert(ctx, NULL, ctx->error_depth, err)) == 0)
232 /* Verify chain signatures and expiration times */
233 ok = (ctx->verify != NULL) ? ctx->verify(ctx) : internal_verify(ctx);
237 #ifndef OPENSSL_NO_RFC3779
238 /* RFC 3779 path validation, now that CRL check has been done */
239 if ((ok = X509v3_asid_validate_path(ctx)) == 0)
241 if ((ok = X509v3_addr_validate_path(ctx)) == 0)
245 /* If we get this far evaluate policies */
246 if (ctx->param->flags & X509_V_FLAG_POLICY_CHECK)
247 ok = ctx->check_policy(ctx);
251 int X509_verify_cert(X509_STORE_CTX *ctx)
253 SSL_DANE *dane = ctx->dane;
255 if (ctx->cert == NULL) {
256 X509err(X509_F_X509_VERIFY_CERT, X509_R_NO_CERT_SET_FOR_US_TO_VERIFY);
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);
270 * first we make sure the chain we are going to build is present and that
271 * the first entry is in place
273 if (((ctx->chain = sk_X509_new_null()) == NULL) ||
274 (!sk_X509_push(ctx->chain, ctx->cert))) {
275 X509err(X509_F_X509_VERIFY_CERT, ERR_R_MALLOC_FAILURE);
278 X509_up_ref(ctx->cert);
279 ctx->num_untrusted = 1;
281 /* If the peer's public key is too weak, we can stop early. */
282 if (!check_key_level(ctx, ctx->cert) &&
283 !verify_cb_cert(ctx, ctx->cert, 0, X509_V_ERR_EE_KEY_TOO_SMALL))
287 * If dane->trecs is an empty stack, we'll fail, since the user enabled
288 * DANE. If none of the TLSA records were usable, and it makes sense to
289 * keep going with an unauthenticated handshake, they can handle that in
290 * the verify callback, or not set SSL_VERIFY_PEER.
292 if (DANETLS_ENABLED(dane))
293 return dane_verify(ctx);
294 return verify_chain(ctx);
298 * Given a STACK_OF(X509) find the issuer of cert (if any)
300 static X509 *find_issuer(X509_STORE_CTX *ctx, STACK_OF(X509) *sk, X509 *x)
304 for (i = 0; i < sk_X509_num(sk); i++) {
305 X509 *issuer = sk_X509_value(sk, i);
307 if (!ctx->check_issued(ctx, x, issuer))
309 if (x509_check_cert_time(ctx, issuer, -1))
315 /* Given a possible certificate and issuer check them */
317 static int check_issued(X509_STORE_CTX *ctx, X509 *x, X509 *issuer)
321 return cert_self_signed(x);
322 ret = X509_check_issued(issuer, x);
323 if (ret == X509_V_OK) {
326 /* Special case: single self signed certificate */
327 if (cert_self_signed(x) && sk_X509_num(ctx->chain) == 1)
329 for (i = 0; i < sk_X509_num(ctx->chain); i++) {
330 ch = sk_X509_value(ctx->chain, i);
331 if (ch == issuer || !X509_cmp(ch, issuer)) {
332 ret = X509_V_ERR_PATH_LOOP;
338 return (ret == X509_V_OK);
341 /* Alternative lookup method: look from a STACK stored in other_ctx */
343 static int get_issuer_sk(X509 **issuer, X509_STORE_CTX *ctx, X509 *x)
345 *issuer = find_issuer(ctx, ctx->other_ctx, x);
347 X509_up_ref(*issuer);
353 static STACK_OF(X509) *lookup_certs_sk(X509_STORE_CTX *ctx, X509_NAME *nm)
355 STACK_OF(X509) *sk = NULL;
358 for (i = 0; i < sk_X509_num(ctx->other_ctx); i++) {
359 x = sk_X509_value(ctx->other_ctx, i);
360 if (X509_NAME_cmp(nm, X509_get_subject_name(x)) == 0) {
362 sk = sk_X509_new_null();
363 if (sk == NULL || sk_X509_push(sk, x) == 0) {
364 sk_X509_pop_free(sk, X509_free);
374 * Check EE or CA certificate purpose. For trusted certificates explicit local
375 * auxiliary trust can be used to override EKU-restrictions.
377 static int check_purpose(X509_STORE_CTX *ctx, X509 *x, int purpose, int depth,
380 int tr_ok = X509_TRUST_UNTRUSTED;
383 * For trusted certificates we want to see whether any auxiliary trust
384 * settings trump the purpose constraints.
386 * This is complicated by the fact that the trust ordinals in
387 * ctx->param->trust are entirely independent of the purpose ordinals in
388 * ctx->param->purpose!
390 * What connects them is their mutual initialization via calls from
391 * X509_STORE_CTX_set_default() into X509_VERIFY_PARAM_lookup() which sets
392 * related values of both param->trust and param->purpose. It is however
393 * typically possible to infer associated trust values from a purpose value
394 * via the X509_PURPOSE API.
396 * Therefore, we can only check for trust overrides when the purpose we're
397 * checking is the same as ctx->param->purpose and ctx->param->trust is
400 if (depth >= ctx->num_untrusted && purpose == ctx->param->purpose)
401 tr_ok = X509_check_trust(x, ctx->param->trust, X509_TRUST_NO_SS_COMPAT);
404 case X509_TRUST_TRUSTED:
406 case X509_TRUST_REJECTED:
409 switch (X509_check_purpose(x, purpose, must_be_ca > 0)) {
415 if ((ctx->param->flags & X509_V_FLAG_X509_STRICT) == 0)
421 return verify_cb_cert(ctx, x, depth, X509_V_ERR_INVALID_PURPOSE);
425 * Check a certificate chains extensions for consistency with the supplied
429 static int check_chain_extensions(X509_STORE_CTX *ctx)
431 int i, must_be_ca, plen = 0;
433 int proxy_path_length = 0;
435 int allow_proxy_certs;
436 int num = sk_X509_num(ctx->chain);
439 * must_be_ca can have 1 of 3 values:
440 * -1: we accept both CA and non-CA certificates, to allow direct
441 * use of self-signed certificates (which are marked as CA).
442 * 0: we only accept non-CA certificates. This is currently not
443 * used, but the possibility is present for future extensions.
444 * 1: we only accept CA certificates. This is currently used for
445 * all certificates in the chain except the leaf certificate.
449 /* CRL path validation */
451 allow_proxy_certs = 0;
452 purpose = X509_PURPOSE_CRL_SIGN;
455 ! !(ctx->param->flags & X509_V_FLAG_ALLOW_PROXY_CERTS);
457 * A hack to keep people who don't want to modify their software
460 if (getenv("OPENSSL_ALLOW_PROXY_CERTS"))
461 allow_proxy_certs = 1;
462 purpose = ctx->param->purpose;
465 for (i = 0; i < num; i++) {
467 x = sk_X509_value(ctx->chain, i);
468 if (!(ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL)
469 && (x->ex_flags & EXFLAG_CRITICAL)) {
470 if (!verify_cb_cert(ctx, x, i,
471 X509_V_ERR_UNHANDLED_CRITICAL_EXTENSION))
474 if (!allow_proxy_certs && (x->ex_flags & EXFLAG_PROXY)) {
475 if (!verify_cb_cert(ctx, x, i,
476 X509_V_ERR_PROXY_CERTIFICATES_NOT_ALLOWED))
479 ret = X509_check_ca(x);
480 switch (must_be_ca) {
482 if ((ctx->param->flags & X509_V_FLAG_X509_STRICT)
483 && (ret != 1) && (ret != 0)) {
485 ctx->error = X509_V_ERR_INVALID_CA;
492 ctx->error = X509_V_ERR_INVALID_NON_CA;
497 /* X509_V_FLAG_X509_STRICT is implicit for intermediate CAs */
499 || ((i + 1 < num || ctx->param->flags & X509_V_FLAG_X509_STRICT)
502 ctx->error = X509_V_ERR_INVALID_CA;
507 if (ret == 0 && !verify_cb_cert(ctx, x, i, X509_V_OK))
509 /* check_purpose() makes the callback as needed */
510 if (purpose > 0 && !check_purpose(ctx, x, purpose, i, must_be_ca))
512 /* Check pathlen if not self issued */
513 if ((i > 1) && !(x->ex_flags & EXFLAG_SI)
514 && (x->ex_pathlen != -1)
515 && (plen > (x->ex_pathlen + proxy_path_length + 1))) {
516 if (!verify_cb_cert(ctx, x, i, X509_V_ERR_PATH_LENGTH_EXCEEDED))
519 /* Increment path length if not self issued */
520 if (!(x->ex_flags & EXFLAG_SI))
523 * If this certificate is a proxy certificate, the next certificate
524 * must be another proxy certificate or a EE certificate. If not,
525 * the next certificate must be a CA certificate.
527 if (x->ex_flags & EXFLAG_PROXY) {
528 if (x->ex_pcpathlen != -1 && i > x->ex_pcpathlen) {
529 if (!verify_cb_cert(ctx, x, i,
530 X509_V_ERR_PROXY_PATH_LENGTH_EXCEEDED))
541 static int check_name_constraints(X509_STORE_CTX *ctx)
545 /* Check name constraints for all certificates */
546 for (i = sk_X509_num(ctx->chain) - 1; i >= 0; i--) {
547 X509 *x = sk_X509_value(ctx->chain, i);
550 /* Ignore self issued certs unless last in chain */
551 if (i && (x->ex_flags & EXFLAG_SI))
554 * Check against constraints for all certificates higher in chain
555 * including trust anchor. Trust anchor not strictly speaking needed
556 * but if it includes constraints it is to be assumed it expects them
559 for (j = sk_X509_num(ctx->chain) - 1; j > i; j--) {
560 NAME_CONSTRAINTS *nc = sk_X509_value(ctx->chain, j)->nc;
563 int rv = NAME_CONSTRAINTS_check(x, nc);
565 if (rv != X509_V_OK && !verify_cb_cert(ctx, x, i, rv))
573 static int check_id_error(X509_STORE_CTX *ctx, int errcode)
575 return verify_cb_cert(ctx, ctx->cert, 0, errcode);
578 static int check_hosts(X509 *x, X509_VERIFY_PARAM *vpm)
581 int n = sk_OPENSSL_STRING_num(vpm->hosts);
584 if (vpm->peername != NULL) {
585 OPENSSL_free(vpm->peername);
586 vpm->peername = NULL;
588 for (i = 0; i < n; ++i) {
589 name = sk_OPENSSL_STRING_value(vpm->hosts, i);
590 if (X509_check_host(x, name, 0, vpm->hostflags, &vpm->peername) > 0)
596 static int check_id(X509_STORE_CTX *ctx)
598 X509_VERIFY_PARAM *vpm = ctx->param;
600 if (vpm->hosts && check_hosts(x, vpm) <= 0) {
601 if (!check_id_error(ctx, X509_V_ERR_HOSTNAME_MISMATCH))
604 if (vpm->email && X509_check_email(x, vpm->email, vpm->emaillen, 0) <= 0) {
605 if (!check_id_error(ctx, X509_V_ERR_EMAIL_MISMATCH))
608 if (vpm->ip && X509_check_ip(x, vpm->ip, vpm->iplen, 0) <= 0) {
609 if (!check_id_error(ctx, X509_V_ERR_IP_ADDRESS_MISMATCH))
615 static int check_trust(X509_STORE_CTX *ctx, int num_untrusted)
620 SSL_DANE *dane = ctx->dane;
621 int num = sk_X509_num(ctx->chain);
625 * Check for a DANE issuer at depth 1 or greater, if it is a DANE-TA(2)
626 * match, we're done, otherwise we'll merely record the match depth.
628 if (DANETLS_HAS_TA(dane) && num_untrusted > 0 && num_untrusted < num) {
629 switch (trust = check_dane_issuer(ctx, num_untrusted)) {
630 case X509_TRUST_TRUSTED:
631 case X509_TRUST_REJECTED:
637 * Check trusted certificates in chain at depth num_untrusted and up.
638 * Note, that depths 0..num_untrusted-1 may also contain trusted
639 * certificates, but the caller is expected to have already checked those,
640 * and wants to incrementally check just any added since.
642 for (i = num_untrusted; i < num; i++) {
643 x = sk_X509_value(ctx->chain, i);
644 trust = X509_check_trust(x, ctx->param->trust, 0);
645 /* If explicitly trusted return trusted */
646 if (trust == X509_TRUST_TRUSTED)
648 if (trust == X509_TRUST_REJECTED)
653 * If we are looking at a trusted certificate, and accept partial chains,
654 * the chain is PKIX trusted.
656 if (num_untrusted < num) {
657 if (ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN)
659 return X509_TRUST_UNTRUSTED;
662 if (num_untrusted == num && ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) {
664 * Last-resort call with no new trusted certificates, check the leaf
665 * for a direct trust store match.
668 x = sk_X509_value(ctx->chain, i);
669 mx = lookup_cert_match(ctx, x);
671 return X509_TRUST_UNTRUSTED;
674 * Check explicit auxiliary trust/reject settings. If none are set,
675 * we'll accept X509_TRUST_UNTRUSTED when not self-signed.
677 trust = X509_check_trust(mx, ctx->param->trust, 0);
678 if (trust == X509_TRUST_REJECTED) {
683 /* Replace leaf with trusted match */
684 (void) sk_X509_set(ctx->chain, 0, mx);
686 ctx->num_untrusted = 0;
691 * If no trusted certs in chain at all return untrusted and allow
692 * standard (no issuer cert) etc errors to be indicated.
694 return X509_TRUST_UNTRUSTED;
697 if (!verify_cb_cert(ctx, x, i, X509_V_ERR_CERT_REJECTED))
698 return X509_TRUST_REJECTED;
699 return X509_TRUST_UNTRUSTED;
702 if (!DANETLS_ENABLED(dane))
703 return X509_TRUST_TRUSTED;
705 dane->pdpth = num_untrusted;
706 /* With DANE, PKIX alone is not trusted until we have both */
707 if (dane->mdpth >= 0)
708 return X509_TRUST_TRUSTED;
709 return X509_TRUST_UNTRUSTED;
712 static int check_revocation(X509_STORE_CTX *ctx)
714 int i = 0, last = 0, ok = 0;
715 if (!(ctx->param->flags & X509_V_FLAG_CRL_CHECK))
717 if (ctx->param->flags & X509_V_FLAG_CRL_CHECK_ALL)
718 last = sk_X509_num(ctx->chain) - 1;
720 /* If checking CRL paths this isn't the EE certificate */
725 for (i = 0; i <= last; i++) {
726 ctx->error_depth = i;
727 ok = check_cert(ctx);
734 static int check_cert(X509_STORE_CTX *ctx)
736 X509_CRL *crl = NULL, *dcrl = NULL;
738 int cnum = ctx->error_depth;
739 X509 *x = sk_X509_value(ctx->chain, cnum);
741 ctx->current_cert = x;
742 ctx->current_issuer = NULL;
743 ctx->current_crl_score = 0;
744 ctx->current_reasons = 0;
746 while (ctx->current_reasons != CRLDP_ALL_REASONS) {
747 unsigned int last_reasons = ctx->current_reasons;
749 /* Try to retrieve relevant CRL */
751 ok = ctx->get_crl(ctx, &crl, x);
753 ok = get_crl_delta(ctx, &crl, &dcrl, x);
755 * If error looking up CRL, nothing we can do except notify callback
758 ok = verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL);
761 ctx->current_crl = crl;
762 ok = ctx->check_crl(ctx, crl);
767 ok = ctx->check_crl(ctx, dcrl);
770 ok = ctx->cert_crl(ctx, dcrl, x);
776 /* Don't look in full CRL if delta reason is removefromCRL */
778 ok = ctx->cert_crl(ctx, crl, x);
788 * If reasons not updated we wont get anywhere by another iteration,
791 if (last_reasons == ctx->current_reasons) {
792 ok = verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL);
800 ctx->current_crl = NULL;
804 /* Check CRL times against values in X509_STORE_CTX */
806 static int check_crl_time(X509_STORE_CTX *ctx, X509_CRL *crl, int notify)
812 ctx->current_crl = crl;
813 if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME)
814 ptime = &ctx->param->check_time;
815 else if (ctx->param->flags & X509_V_FLAG_NO_CHECK_TIME)
820 i = X509_cmp_time(X509_CRL_get_lastUpdate(crl), ptime);
824 if (!verify_cb_crl(ctx, X509_V_ERR_ERROR_IN_CRL_LAST_UPDATE_FIELD))
831 if (!verify_cb_crl(ctx, X509_V_ERR_CRL_NOT_YET_VALID))
835 if (X509_CRL_get_nextUpdate(crl)) {
836 i = X509_cmp_time(X509_CRL_get_nextUpdate(crl), ptime);
841 if (!verify_cb_crl(ctx, X509_V_ERR_ERROR_IN_CRL_NEXT_UPDATE_FIELD))
844 /* Ignore expiry of base CRL is delta is valid */
845 if ((i < 0) && !(ctx->current_crl_score & CRL_SCORE_TIME_DELTA)) {
848 if (!verify_cb_crl(ctx, X509_V_ERR_CRL_HAS_EXPIRED))
854 ctx->current_crl = NULL;
859 static int get_crl_sk(X509_STORE_CTX *ctx, X509_CRL **pcrl, X509_CRL **pdcrl,
860 X509 **pissuer, int *pscore, unsigned int *preasons,
861 STACK_OF(X509_CRL) *crls)
863 int i, crl_score, best_score = *pscore;
864 unsigned int reasons, best_reasons = 0;
865 X509 *x = ctx->current_cert;
866 X509_CRL *crl, *best_crl = NULL;
867 X509 *crl_issuer = NULL, *best_crl_issuer = NULL;
869 for (i = 0; i < sk_X509_CRL_num(crls); i++) {
870 crl = sk_X509_CRL_value(crls, i);
872 crl_score = get_crl_score(ctx, &crl_issuer, &reasons, crl, x);
874 if (crl_score > best_score) {
876 best_crl_issuer = crl_issuer;
877 best_score = crl_score;
878 best_reasons = reasons;
883 X509_CRL_free(*pcrl);
885 *pissuer = best_crl_issuer;
886 *pscore = best_score;
887 *preasons = best_reasons;
888 X509_CRL_up_ref(best_crl);
889 X509_CRL_free(*pdcrl);
891 get_delta_sk(ctx, pdcrl, pscore, best_crl, crls);
894 if (best_score >= CRL_SCORE_VALID)
901 * Compare two CRL extensions for delta checking purposes. They should be
902 * both present or both absent. If both present all fields must be identical.
905 static int crl_extension_match(X509_CRL *a, X509_CRL *b, int nid)
907 ASN1_OCTET_STRING *exta, *extb;
909 i = X509_CRL_get_ext_by_NID(a, nid, -1);
911 /* Can't have multiple occurrences */
912 if (X509_CRL_get_ext_by_NID(a, nid, i) != -1)
914 exta = X509_EXTENSION_get_data(X509_CRL_get_ext(a, i));
918 i = X509_CRL_get_ext_by_NID(b, nid, -1);
922 if (X509_CRL_get_ext_by_NID(b, nid, i) != -1)
924 extb = X509_EXTENSION_get_data(X509_CRL_get_ext(b, i));
934 if (ASN1_OCTET_STRING_cmp(exta, extb))
940 /* See if a base and delta are compatible */
942 static int check_delta_base(X509_CRL *delta, X509_CRL *base)
944 /* Delta CRL must be a delta */
945 if (!delta->base_crl_number)
947 /* Base must have a CRL number */
948 if (!base->crl_number)
950 /* Issuer names must match */
951 if (X509_NAME_cmp(X509_CRL_get_issuer(base), X509_CRL_get_issuer(delta)))
953 /* AKID and IDP must match */
954 if (!crl_extension_match(delta, base, NID_authority_key_identifier))
956 if (!crl_extension_match(delta, base, NID_issuing_distribution_point))
958 /* Delta CRL base number must not exceed Full CRL number. */
959 if (ASN1_INTEGER_cmp(delta->base_crl_number, base->crl_number) > 0)
961 /* Delta CRL number must exceed full CRL number */
962 if (ASN1_INTEGER_cmp(delta->crl_number, base->crl_number) > 0)
968 * For a given base CRL find a delta... maybe extend to delta scoring or
969 * retrieve a chain of deltas...
972 static void get_delta_sk(X509_STORE_CTX *ctx, X509_CRL **dcrl, int *pscore,
973 X509_CRL *base, STACK_OF(X509_CRL) *crls)
977 if (!(ctx->param->flags & X509_V_FLAG_USE_DELTAS))
979 if (!((ctx->current_cert->ex_flags | base->flags) & EXFLAG_FRESHEST))
981 for (i = 0; i < sk_X509_CRL_num(crls); i++) {
982 delta = sk_X509_CRL_value(crls, i);
983 if (check_delta_base(delta, base)) {
984 if (check_crl_time(ctx, delta, 0))
985 *pscore |= CRL_SCORE_TIME_DELTA;
986 X509_CRL_up_ref(delta);
995 * For a given CRL return how suitable it is for the supplied certificate
996 * 'x'. The return value is a mask of several criteria. If the issuer is not
997 * the certificate issuer this is returned in *pissuer. The reasons mask is
998 * also used to determine if the CRL is suitable: if no new reasons the CRL
999 * is rejected, otherwise reasons is updated.
1002 static int get_crl_score(X509_STORE_CTX *ctx, X509 **pissuer,
1003 unsigned int *preasons, X509_CRL *crl, X509 *x)
1007 unsigned int tmp_reasons = *preasons, crl_reasons;
1009 /* First see if we can reject CRL straight away */
1011 /* Invalid IDP cannot be processed */
1012 if (crl->idp_flags & IDP_INVALID)
1014 /* Reason codes or indirect CRLs need extended CRL support */
1015 if (!(ctx->param->flags & X509_V_FLAG_EXTENDED_CRL_SUPPORT)) {
1016 if (crl->idp_flags & (IDP_INDIRECT | IDP_REASONS))
1018 } else if (crl->idp_flags & IDP_REASONS) {
1019 /* If no new reasons reject */
1020 if (!(crl->idp_reasons & ~tmp_reasons))
1023 /* Don't process deltas at this stage */
1024 else if (crl->base_crl_number)
1026 /* If issuer name doesn't match certificate need indirect CRL */
1027 if (X509_NAME_cmp(X509_get_issuer_name(x), X509_CRL_get_issuer(crl))) {
1028 if (!(crl->idp_flags & IDP_INDIRECT))
1031 crl_score |= CRL_SCORE_ISSUER_NAME;
1033 if (!(crl->flags & EXFLAG_CRITICAL))
1034 crl_score |= CRL_SCORE_NOCRITICAL;
1037 if (check_crl_time(ctx, crl, 0))
1038 crl_score |= CRL_SCORE_TIME;
1040 /* Check authority key ID and locate certificate issuer */
1041 crl_akid_check(ctx, crl, pissuer, &crl_score);
1043 /* If we can't locate certificate issuer at this point forget it */
1045 if (!(crl_score & CRL_SCORE_AKID))
1048 /* Check cert for matching CRL distribution points */
1050 if (crl_crldp_check(x, crl, crl_score, &crl_reasons)) {
1051 /* If no new reasons reject */
1052 if (!(crl_reasons & ~tmp_reasons))
1054 tmp_reasons |= crl_reasons;
1055 crl_score |= CRL_SCORE_SCOPE;
1058 *preasons = tmp_reasons;
1064 static void crl_akid_check(X509_STORE_CTX *ctx, X509_CRL *crl,
1065 X509 **pissuer, int *pcrl_score)
1067 X509 *crl_issuer = NULL;
1068 X509_NAME *cnm = X509_CRL_get_issuer(crl);
1069 int cidx = ctx->error_depth;
1072 if (cidx != sk_X509_num(ctx->chain) - 1)
1075 crl_issuer = sk_X509_value(ctx->chain, cidx);
1077 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1078 if (*pcrl_score & CRL_SCORE_ISSUER_NAME) {
1079 *pcrl_score |= CRL_SCORE_AKID | CRL_SCORE_ISSUER_CERT;
1080 *pissuer = crl_issuer;
1085 for (cidx++; cidx < sk_X509_num(ctx->chain); cidx++) {
1086 crl_issuer = sk_X509_value(ctx->chain, cidx);
1087 if (X509_NAME_cmp(X509_get_subject_name(crl_issuer), cnm))
1089 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1090 *pcrl_score |= CRL_SCORE_AKID | CRL_SCORE_SAME_PATH;
1091 *pissuer = crl_issuer;
1096 /* Anything else needs extended CRL support */
1098 if (!(ctx->param->flags & X509_V_FLAG_EXTENDED_CRL_SUPPORT))
1102 * Otherwise the CRL issuer is not on the path. Look for it in the set of
1103 * untrusted certificates.
1105 for (i = 0; i < sk_X509_num(ctx->untrusted); i++) {
1106 crl_issuer = sk_X509_value(ctx->untrusted, i);
1107 if (X509_NAME_cmp(X509_get_subject_name(crl_issuer), cnm))
1109 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1110 *pissuer = crl_issuer;
1111 *pcrl_score |= CRL_SCORE_AKID;
1118 * Check the path of a CRL issuer certificate. This creates a new
1119 * X509_STORE_CTX and populates it with most of the parameters from the
1120 * parent. This could be optimised somewhat since a lot of path checking will
1121 * be duplicated by the parent, but this will rarely be used in practice.
1124 static int check_crl_path(X509_STORE_CTX *ctx, X509 *x)
1126 X509_STORE_CTX crl_ctx;
1129 /* Don't allow recursive CRL path validation */
1132 if (!X509_STORE_CTX_init(&crl_ctx, ctx->ctx, x, ctx->untrusted))
1135 crl_ctx.crls = ctx->crls;
1136 /* Copy verify params across */
1137 X509_STORE_CTX_set0_param(&crl_ctx, ctx->param);
1139 crl_ctx.parent = ctx;
1140 crl_ctx.verify_cb = ctx->verify_cb;
1142 /* Verify CRL issuer */
1143 ret = X509_verify_cert(&crl_ctx);
1147 /* Check chain is acceptable */
1148 ret = check_crl_chain(ctx, ctx->chain, crl_ctx.chain);
1150 X509_STORE_CTX_cleanup(&crl_ctx);
1155 * RFC3280 says nothing about the relationship between CRL path and
1156 * certificate path, which could lead to situations where a certificate could
1157 * be revoked or validated by a CA not authorised to do so. RFC5280 is more
1158 * strict and states that the two paths must end in the same trust anchor,
1159 * though some discussions remain... until this is resolved we use the
1163 static int check_crl_chain(X509_STORE_CTX *ctx,
1164 STACK_OF(X509) *cert_path,
1165 STACK_OF(X509) *crl_path)
1167 X509 *cert_ta, *crl_ta;
1168 cert_ta = sk_X509_value(cert_path, sk_X509_num(cert_path) - 1);
1169 crl_ta = sk_X509_value(crl_path, sk_X509_num(crl_path) - 1);
1170 if (!X509_cmp(cert_ta, crl_ta))
1176 * Check for match between two dist point names: three separate cases.
1177 * 1. Both are relative names and compare X509_NAME types.
1178 * 2. One full, one relative. Compare X509_NAME to GENERAL_NAMES.
1179 * 3. Both are full names and compare two GENERAL_NAMES.
1180 * 4. One is NULL: automatic match.
1183 static int idp_check_dp(DIST_POINT_NAME *a, DIST_POINT_NAME *b)
1185 X509_NAME *nm = NULL;
1186 GENERAL_NAMES *gens = NULL;
1187 GENERAL_NAME *gena, *genb;
1194 /* Case 1: two X509_NAME */
1198 if (!X509_NAME_cmp(a->dpname, b->dpname))
1203 /* Case 2: set name and GENERAL_NAMES appropriately */
1205 gens = b->name.fullname;
1206 } else if (b->type == 1) {
1209 /* Case 2: set name and GENERAL_NAMES appropriately */
1210 gens = a->name.fullname;
1214 /* Handle case 2 with one GENERAL_NAMES and one X509_NAME */
1216 for (i = 0; i < sk_GENERAL_NAME_num(gens); i++) {
1217 gena = sk_GENERAL_NAME_value(gens, i);
1218 if (gena->type != GEN_DIRNAME)
1220 if (!X509_NAME_cmp(nm, gena->d.directoryName))
1226 /* Else case 3: two GENERAL_NAMES */
1228 for (i = 0; i < sk_GENERAL_NAME_num(a->name.fullname); i++) {
1229 gena = sk_GENERAL_NAME_value(a->name.fullname, i);
1230 for (j = 0; j < sk_GENERAL_NAME_num(b->name.fullname); j++) {
1231 genb = sk_GENERAL_NAME_value(b->name.fullname, j);
1232 if (!GENERAL_NAME_cmp(gena, genb))
1241 static int crldp_check_crlissuer(DIST_POINT *dp, X509_CRL *crl, int crl_score)
1244 X509_NAME *nm = X509_CRL_get_issuer(crl);
1245 /* If no CRLissuer return is successful iff don't need a match */
1247 return ! !(crl_score & CRL_SCORE_ISSUER_NAME);
1248 for (i = 0; i < sk_GENERAL_NAME_num(dp->CRLissuer); i++) {
1249 GENERAL_NAME *gen = sk_GENERAL_NAME_value(dp->CRLissuer, i);
1250 if (gen->type != GEN_DIRNAME)
1252 if (!X509_NAME_cmp(gen->d.directoryName, nm))
1258 /* Check CRLDP and IDP */
1260 static int crl_crldp_check(X509 *x, X509_CRL *crl, int crl_score,
1261 unsigned int *preasons)
1264 if (crl->idp_flags & IDP_ONLYATTR)
1266 if (x->ex_flags & EXFLAG_CA) {
1267 if (crl->idp_flags & IDP_ONLYUSER)
1270 if (crl->idp_flags & IDP_ONLYCA)
1273 *preasons = crl->idp_reasons;
1274 for (i = 0; i < sk_DIST_POINT_num(x->crldp); i++) {
1275 DIST_POINT *dp = sk_DIST_POINT_value(x->crldp, i);
1276 if (crldp_check_crlissuer(dp, crl, crl_score)) {
1277 if (!crl->idp || idp_check_dp(dp->distpoint, crl->idp->distpoint)) {
1278 *preasons &= dp->dp_reasons;
1283 if ((!crl->idp || !crl->idp->distpoint)
1284 && (crl_score & CRL_SCORE_ISSUER_NAME))
1290 * Retrieve CRL corresponding to current certificate. If deltas enabled try
1291 * to find a delta CRL too
1294 static int get_crl_delta(X509_STORE_CTX *ctx,
1295 X509_CRL **pcrl, X509_CRL **pdcrl, X509 *x)
1298 X509 *issuer = NULL;
1300 unsigned int reasons;
1301 X509_CRL *crl = NULL, *dcrl = NULL;
1302 STACK_OF(X509_CRL) *skcrl;
1303 X509_NAME *nm = X509_get_issuer_name(x);
1305 reasons = ctx->current_reasons;
1306 ok = get_crl_sk(ctx, &crl, &dcrl,
1307 &issuer, &crl_score, &reasons, ctx->crls);
1311 /* Lookup CRLs from store */
1313 skcrl = ctx->lookup_crls(ctx, nm);
1315 /* If no CRLs found and a near match from get_crl_sk use that */
1319 get_crl_sk(ctx, &crl, &dcrl, &issuer, &crl_score, &reasons, skcrl);
1321 sk_X509_CRL_pop_free(skcrl, X509_CRL_free);
1324 /* If we got any kind of CRL use it and return success */
1326 ctx->current_issuer = issuer;
1327 ctx->current_crl_score = crl_score;
1328 ctx->current_reasons = reasons;
1336 /* Check CRL validity */
1337 static int check_crl(X509_STORE_CTX *ctx, X509_CRL *crl)
1339 X509 *issuer = NULL;
1340 EVP_PKEY *ikey = NULL;
1341 int cnum = ctx->error_depth;
1342 int chnum = sk_X509_num(ctx->chain) - 1;
1344 /* if we have an alternative CRL issuer cert use that */
1345 if (ctx->current_issuer)
1346 issuer = ctx->current_issuer;
1348 * Else find CRL issuer: if not last certificate then issuer is next
1349 * certificate in chain.
1351 else if (cnum < chnum)
1352 issuer = sk_X509_value(ctx->chain, cnum + 1);
1354 issuer = sk_X509_value(ctx->chain, chnum);
1355 /* If not self signed, can't check signature */
1356 if (!ctx->check_issued(ctx, issuer, issuer) &&
1357 !verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL_ISSUER))
1365 * Skip most tests for deltas because they have already been done
1367 if (!crl->base_crl_number) {
1368 /* Check for cRLSign bit if keyUsage present */
1369 if ((issuer->ex_flags & EXFLAG_KUSAGE) &&
1370 !(issuer->ex_kusage & KU_CRL_SIGN) &&
1371 !verify_cb_crl(ctx, X509_V_ERR_KEYUSAGE_NO_CRL_SIGN))
1374 if (!(ctx->current_crl_score & CRL_SCORE_SCOPE) &&
1375 !verify_cb_crl(ctx, X509_V_ERR_DIFFERENT_CRL_SCOPE))
1378 if (!(ctx->current_crl_score & CRL_SCORE_SAME_PATH) &&
1379 check_crl_path(ctx, ctx->current_issuer) <= 0 &&
1380 !verify_cb_crl(ctx, X509_V_ERR_CRL_PATH_VALIDATION_ERROR))
1383 if ((crl->idp_flags & IDP_INVALID) &&
1384 !verify_cb_crl(ctx, X509_V_ERR_INVALID_EXTENSION))
1388 if (!(ctx->current_crl_score & CRL_SCORE_TIME) &&
1389 !check_crl_time(ctx, crl, 1))
1392 /* Attempt to get issuer certificate public key */
1393 ikey = X509_get0_pubkey(issuer);
1396 !verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY))
1400 int rv = X509_CRL_check_suiteb(crl, ikey, ctx->param->flags);
1402 if (rv != X509_V_OK && !verify_cb_crl(ctx, rv))
1404 /* Verify CRL signature */
1405 if (X509_CRL_verify(crl, ikey) <= 0 &&
1406 !verify_cb_crl(ctx, X509_V_ERR_CRL_SIGNATURE_FAILURE))
1412 /* Check certificate against CRL */
1413 static int cert_crl(X509_STORE_CTX *ctx, X509_CRL *crl, X509 *x)
1418 * The rules changed for this... previously if a CRL contained unhandled
1419 * critical extensions it could still be used to indicate a certificate
1420 * was revoked. This has since been changed since critical extensions can
1421 * change the meaning of CRL entries.
1423 if (!(ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL)
1424 && (crl->flags & EXFLAG_CRITICAL) &&
1425 !verify_cb_crl(ctx, X509_V_ERR_UNHANDLED_CRITICAL_CRL_EXTENSION))
1428 * Look for serial number of certificate in CRL. If found, make sure
1429 * reason is not removeFromCRL.
1431 if (X509_CRL_get0_by_cert(crl, &rev, x)) {
1432 if (rev->reason == CRL_REASON_REMOVE_FROM_CRL)
1434 if (!verify_cb_crl(ctx, X509_V_ERR_CERT_REVOKED))
1441 static int check_policy(X509_STORE_CTX *ctx)
1448 * With DANE, the trust anchor might be a bare public key, not a
1449 * certificate! In that case our chain does not have the trust anchor
1450 * certificate as a top-most element. This comports well with RFC5280
1451 * chain verification, since there too, the trust anchor is not part of the
1452 * chain to be verified. In particular, X509_policy_check() does not look
1453 * at the TA cert, but assumes that it is present as the top-most chain
1454 * element. We therefore temporarily push a NULL cert onto the chain if it
1455 * was verified via a bare public key, and pop it off right after the
1456 * X509_policy_check() call.
1458 if (ctx->bare_ta_signed && !sk_X509_push(ctx->chain, NULL)) {
1459 X509err(X509_F_CHECK_POLICY, ERR_R_MALLOC_FAILURE);
1462 ret = X509_policy_check(&ctx->tree, &ctx->explicit_policy, ctx->chain,
1463 ctx->param->policies, ctx->param->flags);
1464 if (ctx->bare_ta_signed)
1465 sk_X509_pop(ctx->chain);
1467 if (ret == X509_PCY_TREE_INTERNAL) {
1468 X509err(X509_F_CHECK_POLICY, ERR_R_MALLOC_FAILURE);
1471 /* Invalid or inconsistent extensions */
1472 if (ret == X509_PCY_TREE_INVALID) {
1475 /* Locate certificates with bad extensions and notify callback. */
1476 for (i = 1; i < sk_X509_num(ctx->chain); i++) {
1477 X509 *x = sk_X509_value(ctx->chain, i);
1479 if (!(x->ex_flags & EXFLAG_INVALID_POLICY))
1481 if (!verify_cb_cert(ctx, x, i,
1482 X509_V_ERR_INVALID_POLICY_EXTENSION))
1487 if (ret == X509_PCY_TREE_FAILURE) {
1488 ctx->current_cert = NULL;
1489 ctx->error = X509_V_ERR_NO_EXPLICIT_POLICY;
1490 return ctx->verify_cb(0, ctx);
1492 if (ret != X509_PCY_TREE_VALID) {
1493 X509err(X509_F_CHECK_POLICY, ERR_R_INTERNAL_ERROR);
1497 if (ctx->param->flags & X509_V_FLAG_NOTIFY_POLICY) {
1498 ctx->current_cert = NULL;
1499 ctx->error = X509_V_OK;
1500 if (!ctx->verify_cb(2, ctx))
1508 * Check certificate validity times.
1509 * If depth >= 0, invoke verification callbacks on error, otherwise just return
1510 * the validation status.
1512 * Return 1 on success, 0 otherwise.
1514 int x509_check_cert_time(X509_STORE_CTX *ctx, X509 *x, int depth)
1519 if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME)
1520 ptime = &ctx->param->check_time;
1521 else if (ctx->param->flags & X509_V_FLAG_NO_CHECK_TIME)
1526 i = X509_cmp_time(X509_get_notBefore(x), ptime);
1527 if (i >= 0 && depth < 0)
1529 if (i == 0 && !verify_cb_cert(ctx, x, depth,
1530 X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD))
1532 if (i > 0 && !verify_cb_cert(ctx, x, depth, X509_V_ERR_CERT_NOT_YET_VALID))
1535 i = X509_cmp_time(X509_get_notAfter(x), ptime);
1536 if (i <= 0 && depth < 0)
1538 if (i == 0 && !verify_cb_cert(ctx, x, depth,
1539 X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD))
1541 if (i < 0 && !verify_cb_cert(ctx, x, depth, X509_V_ERR_CERT_HAS_EXPIRED))
1546 static int internal_verify(X509_STORE_CTX *ctx)
1548 int n = sk_X509_num(ctx->chain) - 1;
1549 X509 *xi = sk_X509_value(ctx->chain, n);
1553 * With DANE-verified bare public key TA signatures, it remains only to
1554 * check the timestamps of the top certificate. We report the issuer as
1555 * NULL, since all we have is a bare key.
1557 if (ctx->bare_ta_signed) {
1563 if (ctx->check_issued(ctx, xi, xi))
1566 if (ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) {
1571 return verify_cb_cert(ctx, xi, 0,
1572 X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE);
1574 ctx->error_depth = n;
1575 xs = sk_X509_value(ctx->chain, n);
1579 * Do not clear ctx->error=0, it must be "sticky", only the user's callback
1580 * is allowed to reset errors (at its own peril).
1586 * Skip signature check for self signed certificates unless explicitly
1587 * asked for. It doesn't add any security and just wastes time. If
1588 * the issuer's public key is unusable, report the issuer certificate
1589 * and its depth (rather than the depth of the subject).
1591 if (xs != xi || (ctx->param->flags & X509_V_FLAG_CHECK_SS_SIGNATURE)) {
1592 if ((pkey = X509_get0_pubkey(xi)) == NULL) {
1593 if (!verify_cb_cert(ctx, xi, xi != xs ? n+1 : n,
1594 X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY))
1596 } else if (X509_verify(xs, pkey) <= 0) {
1597 if (!verify_cb_cert(ctx, xs, n,
1598 X509_V_ERR_CERT_SIGNATURE_FAILURE))
1604 /* Calls verify callback as needed */
1605 if (!x509_check_cert_time(ctx, xs, n))
1609 * Signal success at this depth. However, the previous error (if any)
1612 ctx->current_issuer = xi;
1613 ctx->current_cert = xs;
1614 ctx->error_depth = n;
1615 if (!ctx->verify_cb(1, ctx))
1620 xs = sk_X509_value(ctx->chain, n);
1626 int X509_cmp_current_time(const ASN1_TIME *ctm)
1628 return X509_cmp_time(ctm, NULL);
1631 int X509_cmp_time(const ASN1_TIME *ctm, time_t *cmp_time)
1636 char buff1[24], buff2[24], *p;
1637 int i, j, remaining;
1640 remaining = ctm->length;
1641 str = (char *)ctm->data;
1643 * Note that the following (historical) code allows much more slack in the
1644 * time format than RFC5280. In RFC5280, the representation is fixed:
1645 * UTCTime: YYMMDDHHMMSSZ
1646 * GeneralizedTime: YYYYMMDDHHMMSSZ
1648 if (ctm->type == V_ASN1_UTCTIME) {
1649 /* YYMMDDHHMM[SS]Z or YYMMDDHHMM[SS](+-)hhmm */
1650 int min_length = sizeof("YYMMDDHHMMZ") - 1;
1651 int max_length = sizeof("YYMMDDHHMMSS+hhmm") - 1;
1652 if (remaining < min_length || remaining > max_length)
1659 /* YYYYMMDDHHMM[SS[.fff]]Z or YYYYMMDDHHMM[SS[.f[f[f]]]](+-)hhmm */
1660 int min_length = sizeof("YYYYMMDDHHMMZ") - 1;
1661 int max_length = sizeof("YYYYMMDDHHMMSS.fff+hhmm") - 1;
1662 if (remaining < min_length || remaining > max_length)
1670 if ((*str == 'Z') || (*str == '-') || (*str == '+')) {
1681 * Skip any (up to three) fractional seconds...
1682 * TODO(emilia): in RFC5280, fractional seconds are forbidden.
1683 * Can we just kill them altogether?
1685 if (remaining && *str == '.') {
1688 for (i = 0; i < 3 && remaining; i++, str++, remaining--) {
1689 if (*str < '0' || *str > '9')
1698 /* We now need either a terminating 'Z' or an offset. */
1707 if ((*str != '+') && (*str != '-'))
1709 /* Historical behaviour: the (+-)hhmm offset is forbidden in RFC5280. */
1712 if (str[1] < '0' || str[1] > '9' || str[2] < '0' || str[2] > '9' ||
1713 str[3] < '0' || str[3] > '9' || str[4] < '0' || str[4] > '9')
1715 offset = ((str[1] - '0') * 10 + (str[2] - '0')) * 60;
1716 offset += (str[3] - '0') * 10 + (str[4] - '0');
1720 atm.type = ctm->type;
1722 atm.length = sizeof(buff2);
1723 atm.data = (unsigned char *)buff2;
1725 if (X509_time_adj(&atm, offset * 60, cmp_time) == NULL)
1728 if (ctm->type == V_ASN1_UTCTIME) {
1729 i = (buff1[0] - '0') * 10 + (buff1[1] - '0');
1731 i += 100; /* cf. RFC 2459 */
1732 j = (buff2[0] - '0') * 10 + (buff2[1] - '0');
1741 i = strcmp(buff1, buff2);
1742 if (i == 0) /* wait a second then return younger :-) */
1748 ASN1_TIME *X509_gmtime_adj(ASN1_TIME *s, long adj)
1750 return X509_time_adj(s, adj, NULL);
1753 ASN1_TIME *X509_time_adj(ASN1_TIME *s, long offset_sec, time_t *in_tm)
1755 return X509_time_adj_ex(s, 0, offset_sec, in_tm);
1758 ASN1_TIME *X509_time_adj_ex(ASN1_TIME *s,
1759 int offset_day, long offset_sec, time_t *in_tm)
1768 if (s && !(s->flags & ASN1_STRING_FLAG_MSTRING)) {
1769 if (s->type == V_ASN1_UTCTIME)
1770 return ASN1_UTCTIME_adj(s, t, offset_day, offset_sec);
1771 if (s->type == V_ASN1_GENERALIZEDTIME)
1772 return ASN1_GENERALIZEDTIME_adj(s, t, offset_day, offset_sec);
1774 return ASN1_TIME_adj(s, t, offset_day, offset_sec);
1777 int X509_get_pubkey_parameters(EVP_PKEY *pkey, STACK_OF(X509) *chain)
1779 EVP_PKEY *ktmp = NULL, *ktmp2;
1782 if ((pkey != NULL) && !EVP_PKEY_missing_parameters(pkey))
1785 for (i = 0; i < sk_X509_num(chain); i++) {
1786 ktmp = X509_get0_pubkey(sk_X509_value(chain, i));
1788 X509err(X509_F_X509_GET_PUBKEY_PARAMETERS,
1789 X509_R_UNABLE_TO_GET_CERTS_PUBLIC_KEY);
1792 if (!EVP_PKEY_missing_parameters(ktmp))
1796 X509err(X509_F_X509_GET_PUBKEY_PARAMETERS,
1797 X509_R_UNABLE_TO_FIND_PARAMETERS_IN_CHAIN);
1801 /* first, populate the other certs */
1802 for (j = i - 1; j >= 0; j--) {
1803 ktmp2 = X509_get0_pubkey(sk_X509_value(chain, j));
1804 EVP_PKEY_copy_parameters(ktmp2, ktmp);
1808 EVP_PKEY_copy_parameters(pkey, ktmp);
1812 /* Make a delta CRL as the diff between two full CRLs */
1814 X509_CRL *X509_CRL_diff(X509_CRL *base, X509_CRL *newer,
1815 EVP_PKEY *skey, const EVP_MD *md, unsigned int flags)
1817 X509_CRL *crl = NULL;
1819 STACK_OF(X509_REVOKED) *revs = NULL;
1820 /* CRLs can't be delta already */
1821 if (base->base_crl_number || newer->base_crl_number) {
1822 X509err(X509_F_X509_CRL_DIFF, X509_R_CRL_ALREADY_DELTA);
1825 /* Base and new CRL must have a CRL number */
1826 if (!base->crl_number || !newer->crl_number) {
1827 X509err(X509_F_X509_CRL_DIFF, X509_R_NO_CRL_NUMBER);
1830 /* Issuer names must match */
1831 if (X509_NAME_cmp(X509_CRL_get_issuer(base), X509_CRL_get_issuer(newer))) {
1832 X509err(X509_F_X509_CRL_DIFF, X509_R_ISSUER_MISMATCH);
1835 /* AKID and IDP must match */
1836 if (!crl_extension_match(base, newer, NID_authority_key_identifier)) {
1837 X509err(X509_F_X509_CRL_DIFF, X509_R_AKID_MISMATCH);
1840 if (!crl_extension_match(base, newer, NID_issuing_distribution_point)) {
1841 X509err(X509_F_X509_CRL_DIFF, X509_R_IDP_MISMATCH);
1844 /* Newer CRL number must exceed full CRL number */
1845 if (ASN1_INTEGER_cmp(newer->crl_number, base->crl_number) <= 0) {
1846 X509err(X509_F_X509_CRL_DIFF, X509_R_NEWER_CRL_NOT_NEWER);
1849 /* CRLs must verify */
1850 if (skey && (X509_CRL_verify(base, skey) <= 0 ||
1851 X509_CRL_verify(newer, skey) <= 0)) {
1852 X509err(X509_F_X509_CRL_DIFF, X509_R_CRL_VERIFY_FAILURE);
1855 /* Create new CRL */
1856 crl = X509_CRL_new();
1857 if (crl == NULL || !X509_CRL_set_version(crl, 1))
1859 /* Set issuer name */
1860 if (!X509_CRL_set_issuer_name(crl, X509_CRL_get_issuer(newer)))
1863 if (!X509_CRL_set_lastUpdate(crl, X509_CRL_get_lastUpdate(newer)))
1865 if (!X509_CRL_set_nextUpdate(crl, X509_CRL_get_nextUpdate(newer)))
1868 /* Set base CRL number: must be critical */
1870 if (!X509_CRL_add1_ext_i2d(crl, NID_delta_crl, base->crl_number, 1, 0))
1874 * Copy extensions across from newest CRL to delta: this will set CRL
1875 * number to correct value too.
1878 for (i = 0; i < X509_CRL_get_ext_count(newer); i++) {
1879 X509_EXTENSION *ext;
1880 ext = X509_CRL_get_ext(newer, i);
1881 if (!X509_CRL_add_ext(crl, ext, -1))
1885 /* Go through revoked entries, copying as needed */
1887 revs = X509_CRL_get_REVOKED(newer);
1889 for (i = 0; i < sk_X509_REVOKED_num(revs); i++) {
1890 X509_REVOKED *rvn, *rvtmp;
1891 rvn = sk_X509_REVOKED_value(revs, i);
1893 * Add only if not also in base. TODO: need something cleverer here
1894 * for some more complex CRLs covering multiple CAs.
1896 if (!X509_CRL_get0_by_serial(base, &rvtmp, &rvn->serialNumber)) {
1897 rvtmp = X509_REVOKED_dup(rvn);
1900 if (!X509_CRL_add0_revoked(crl, rvtmp)) {
1901 X509_REVOKED_free(rvtmp);
1906 /* TODO: optionally prune deleted entries */
1908 if (skey && md && !X509_CRL_sign(crl, skey, md))
1914 X509err(X509_F_X509_CRL_DIFF, ERR_R_MALLOC_FAILURE);
1919 int X509_STORE_CTX_set_ex_data(X509_STORE_CTX *ctx, int idx, void *data)
1921 return CRYPTO_set_ex_data(&ctx->ex_data, idx, data);
1924 void *X509_STORE_CTX_get_ex_data(X509_STORE_CTX *ctx, int idx)
1926 return CRYPTO_get_ex_data(&ctx->ex_data, idx);
1929 int X509_STORE_CTX_get_error(X509_STORE_CTX *ctx)
1934 void X509_STORE_CTX_set_error(X509_STORE_CTX *ctx, int err)
1939 int X509_STORE_CTX_get_error_depth(X509_STORE_CTX *ctx)
1941 return ctx->error_depth;
1944 void X509_STORE_CTX_set_error_depth(X509_STORE_CTX *ctx, int depth)
1946 ctx->error_depth = depth;
1949 X509 *X509_STORE_CTX_get_current_cert(X509_STORE_CTX *ctx)
1951 return ctx->current_cert;
1954 void X509_STORE_CTX_set_current_cert(X509_STORE_CTX *ctx, X509 *x)
1956 ctx->current_cert = x;
1959 STACK_OF(X509) *X509_STORE_CTX_get0_chain(X509_STORE_CTX *ctx)
1964 STACK_OF(X509) *X509_STORE_CTX_get1_chain(X509_STORE_CTX *ctx)
1968 return X509_chain_up_ref(ctx->chain);
1971 X509 *X509_STORE_CTX_get0_current_issuer(X509_STORE_CTX *ctx)
1973 return ctx->current_issuer;
1976 X509_CRL *X509_STORE_CTX_get0_current_crl(X509_STORE_CTX *ctx)
1978 return ctx->current_crl;
1981 X509_STORE_CTX *X509_STORE_CTX_get0_parent_ctx(X509_STORE_CTX *ctx)
1986 void X509_STORE_CTX_set_cert(X509_STORE_CTX *ctx, X509 *x)
1991 void X509_STORE_CTX_set0_crls(X509_STORE_CTX *ctx, STACK_OF(X509_CRL) *sk)
1996 int X509_STORE_CTX_set_purpose(X509_STORE_CTX *ctx, int purpose)
1999 * XXX: Why isn't this function always used to set the associated trust?
2000 * Should there even be a VPM->trust field at all? Or should the trust
2001 * always be inferred from the purpose by X509_STORE_CTX_init().
2003 return X509_STORE_CTX_purpose_inherit(ctx, 0, purpose, 0);
2006 int X509_STORE_CTX_set_trust(X509_STORE_CTX *ctx, int trust)
2009 * XXX: See above, this function would only be needed when the default
2010 * trust for the purpose needs an override in a corner case.
2012 return X509_STORE_CTX_purpose_inherit(ctx, 0, 0, trust);
2016 * This function is used to set the X509_STORE_CTX purpose and trust values.
2017 * This is intended to be used when another structure has its own trust and
2018 * purpose values which (if set) will be inherited by the ctx. If they aren't
2019 * set then we will usually have a default purpose in mind which should then
2020 * be used to set the trust value. An example of this is SSL use: an SSL
2021 * structure will have its own purpose and trust settings which the
2022 * application can set: if they aren't set then we use the default of SSL
2026 int X509_STORE_CTX_purpose_inherit(X509_STORE_CTX *ctx, int def_purpose,
2027 int purpose, int trust)
2030 /* If purpose not set use default */
2032 purpose = def_purpose;
2033 /* If we have a purpose then check it is valid */
2036 idx = X509_PURPOSE_get_by_id(purpose);
2038 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2039 X509_R_UNKNOWN_PURPOSE_ID);
2042 ptmp = X509_PURPOSE_get0(idx);
2043 if (ptmp->trust == X509_TRUST_DEFAULT) {
2044 idx = X509_PURPOSE_get_by_id(def_purpose);
2046 * XXX: In the two callers above def_purpose is always 0, which is
2047 * not a known value, so idx will always be -1. How is the
2048 * X509_TRUST_DEFAULT case actually supposed to be handled?
2051 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2052 X509_R_UNKNOWN_PURPOSE_ID);
2055 ptmp = X509_PURPOSE_get0(idx);
2057 /* If trust not set then get from purpose default */
2059 trust = ptmp->trust;
2062 idx = X509_TRUST_get_by_id(trust);
2064 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2065 X509_R_UNKNOWN_TRUST_ID);
2070 if (purpose && !ctx->param->purpose)
2071 ctx->param->purpose = purpose;
2072 if (trust && !ctx->param->trust)
2073 ctx->param->trust = trust;
2077 X509_STORE_CTX *X509_STORE_CTX_new(void)
2079 X509_STORE_CTX *ctx = OPENSSL_zalloc(sizeof(*ctx));
2082 X509err(X509_F_X509_STORE_CTX_NEW, ERR_R_MALLOC_FAILURE);
2088 void X509_STORE_CTX_free(X509_STORE_CTX *ctx)
2093 X509_STORE_CTX_cleanup(ctx);
2097 int X509_STORE_CTX_init(X509_STORE_CTX *ctx, X509_STORE *store, X509 *x509,
2098 STACK_OF(X509) *chain)
2103 ctx->current_method = 0;
2105 ctx->untrusted = chain;
2107 ctx->num_untrusted = 0;
2108 ctx->other_ctx = NULL;
2112 ctx->explicit_policy = 0;
2113 ctx->error_depth = 0;
2114 ctx->current_cert = NULL;
2115 ctx->current_issuer = NULL;
2116 ctx->current_crl = NULL;
2117 ctx->current_crl_score = 0;
2118 ctx->current_reasons = 0;
2122 ctx->bare_ta_signed = 0;
2123 /* Zero ex_data to make sure we're cleanup-safe */
2124 memset(&ctx->ex_data, 0, sizeof(ctx->ex_data));
2126 /* store->cleanup is always 0 in OpenSSL, if set must be idempotent */
2128 ctx->cleanup = store->cleanup;
2132 if (store && store->check_issued)
2133 ctx->check_issued = store->check_issued;
2135 ctx->check_issued = check_issued;
2137 if (store && store->get_issuer)
2138 ctx->get_issuer = store->get_issuer;
2140 ctx->get_issuer = X509_STORE_CTX_get1_issuer;
2142 if (store && store->verify_cb)
2143 ctx->verify_cb = store->verify_cb;
2145 ctx->verify_cb = null_callback;
2147 if (store && store->verify)
2148 ctx->verify = store->verify;
2150 ctx->verify = internal_verify;
2152 if (store && store->check_revocation)
2153 ctx->check_revocation = store->check_revocation;
2155 ctx->check_revocation = check_revocation;
2157 if (store && store->get_crl)
2158 ctx->get_crl = store->get_crl;
2160 ctx->get_crl = NULL;
2162 if (store && store->check_crl)
2163 ctx->check_crl = store->check_crl;
2165 ctx->check_crl = check_crl;
2167 if (store && store->cert_crl)
2168 ctx->cert_crl = store->cert_crl;
2170 ctx->cert_crl = cert_crl;
2172 if (store && store->lookup_certs)
2173 ctx->lookup_certs = store->lookup_certs;
2175 ctx->lookup_certs = X509_STORE_get1_certs;
2177 if (store && store->lookup_crls)
2178 ctx->lookup_crls = store->lookup_crls;
2180 ctx->lookup_crls = X509_STORE_get1_crls;
2182 ctx->check_policy = check_policy;
2184 ctx->param = X509_VERIFY_PARAM_new();
2185 if (ctx->param == NULL) {
2186 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2191 * Inherit callbacks and flags from X509_STORE if not set use defaults.
2194 ret = X509_VERIFY_PARAM_inherit(ctx->param, store->param);
2196 ctx->param->inh_flags |= X509_VP_FLAG_DEFAULT | X509_VP_FLAG_ONCE;
2199 ret = X509_VERIFY_PARAM_inherit(ctx->param,
2200 X509_VERIFY_PARAM_lookup("default"));
2203 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2208 * XXX: For now, continue to inherit trust from VPM, but infer from the
2209 * purpose if this still yields the default value.
2211 if (ctx->param->trust == X509_TRUST_DEFAULT) {
2212 int idx = X509_PURPOSE_get_by_id(ctx->param->purpose);
2213 X509_PURPOSE *xp = X509_PURPOSE_get0(idx);
2216 ctx->param->trust = X509_PURPOSE_get_trust(xp);
2219 if (CRYPTO_new_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx,
2222 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2226 * On error clean up allocated storage, if the store context was not
2227 * allocated with X509_STORE_CTX_new() this is our last chance to do so.
2229 X509_STORE_CTX_cleanup(ctx);
2234 * Set alternative lookup method: just a STACK of trusted certificates. This
2235 * avoids X509_STORE nastiness where it isn't needed.
2237 void X509_STORE_CTX_set0_trusted_stack(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2239 ctx->other_ctx = sk;
2240 ctx->get_issuer = get_issuer_sk;
2241 ctx->lookup_certs = lookup_certs_sk;
2244 void X509_STORE_CTX_cleanup(X509_STORE_CTX *ctx)
2247 * We need to be idempotent because, unfortunately, free() also calls
2248 * cleanup(), so the natural call sequence new(), init(), cleanup(), free()
2249 * calls cleanup() for the same object twice! Thus we must zero the
2250 * pointers below after they're freed!
2252 /* Seems to always be 0 in OpenSSL, do this at most once. */
2253 if (ctx->cleanup != NULL) {
2255 ctx->cleanup = NULL;
2257 if (ctx->param != NULL) {
2258 if (ctx->parent == NULL)
2259 X509_VERIFY_PARAM_free(ctx->param);
2262 X509_policy_tree_free(ctx->tree);
2264 sk_X509_pop_free(ctx->chain, X509_free);
2266 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx, &(ctx->ex_data));
2267 memset(&ctx->ex_data, 0, sizeof(ctx->ex_data));
2270 void X509_STORE_CTX_set_depth(X509_STORE_CTX *ctx, int depth)
2272 X509_VERIFY_PARAM_set_depth(ctx->param, depth);
2275 void X509_STORE_CTX_set_flags(X509_STORE_CTX *ctx, unsigned long flags)
2277 X509_VERIFY_PARAM_set_flags(ctx->param, flags);
2280 void X509_STORE_CTX_set_time(X509_STORE_CTX *ctx, unsigned long flags,
2283 X509_VERIFY_PARAM_set_time(ctx->param, t);
2286 void X509_STORE_CTX_set_verify_cb(X509_STORE_CTX *ctx,
2287 X509_STORE_CTX_verify_cb verify_cb)
2289 ctx->verify_cb = verify_cb;
2292 X509_STORE_CTX_verify_cb X509_STORE_CTX_get_verify_cb(X509_STORE_CTX *ctx)
2294 return ctx->verify_cb;
2297 X509 *X509_STORE_CTX_get0_cert(X509_STORE_CTX *ctx)
2302 STACK_OF(X509) *X509_STORE_CTX_get0_untrusted(X509_STORE_CTX *ctx)
2304 return ctx->untrusted;
2307 void X509_STORE_CTX_set0_untrusted(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2309 ctx->untrusted = sk;
2312 void X509_STORE_CTX_set0_verified_chain(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2314 sk_X509_pop_free(ctx->chain, X509_free);
2318 void X509_STORE_CTX_set_verify(X509_STORE_CTX *ctx,
2319 X509_STORE_CTX_verify verify)
2321 ctx->verify = verify;
2324 X509_STORE_CTX_verify X509_STORE_CTX_get_verify(X509_STORE_CTX *ctx)
2329 X509_POLICY_TREE *X509_STORE_CTX_get0_policy_tree(X509_STORE_CTX *ctx)
2334 int X509_STORE_CTX_get_explicit_policy(X509_STORE_CTX *ctx)
2336 return ctx->explicit_policy;
2339 int X509_STORE_CTX_get_num_untrusted(X509_STORE_CTX *ctx)
2341 return ctx->num_untrusted;
2344 int X509_STORE_CTX_set_default(X509_STORE_CTX *ctx, const char *name)
2346 const X509_VERIFY_PARAM *param;
2347 param = X509_VERIFY_PARAM_lookup(name);
2350 return X509_VERIFY_PARAM_inherit(ctx->param, param);
2353 X509_VERIFY_PARAM *X509_STORE_CTX_get0_param(X509_STORE_CTX *ctx)
2358 void X509_STORE_CTX_set0_param(X509_STORE_CTX *ctx, X509_VERIFY_PARAM *param)
2360 X509_VERIFY_PARAM_free(ctx->param);
2364 void X509_STORE_CTX_set0_dane(X509_STORE_CTX *ctx, SSL_DANE *dane)
2369 static unsigned char *dane_i2d(
2372 unsigned int *i2dlen)
2374 unsigned char *buf = NULL;
2378 * Extract ASN.1 DER form of certificate or public key.
2381 case DANETLS_SELECTOR_CERT:
2382 len = i2d_X509(cert, &buf);
2384 case DANETLS_SELECTOR_SPKI:
2385 len = i2d_X509_PUBKEY(X509_get_X509_PUBKEY(cert), &buf);
2388 X509err(X509_F_DANE_I2D, X509_R_BAD_SELECTOR);
2392 if (len < 0 || buf == NULL) {
2393 X509err(X509_F_DANE_I2D, ERR_R_MALLOC_FAILURE);
2397 *i2dlen = (unsigned int)len;
2401 #define DANETLS_NONE 256 /* impossible uint8_t */
2403 static int dane_match(X509_STORE_CTX *ctx, X509 *cert, int depth)
2405 SSL_DANE *dane = ctx->dane;
2406 unsigned usage = DANETLS_NONE;
2407 unsigned selector = DANETLS_NONE;
2408 unsigned ordinal = DANETLS_NONE;
2409 unsigned mtype = DANETLS_NONE;
2410 unsigned char *i2dbuf = NULL;
2411 unsigned int i2dlen = 0;
2412 unsigned char mdbuf[EVP_MAX_MD_SIZE];
2413 unsigned char *cmpbuf = NULL;
2414 unsigned int cmplen = 0;
2418 danetls_record *t = NULL;
2421 mask = (depth == 0) ? DANETLS_EE_MASK : DANETLS_TA_MASK;
2424 * The trust store is not applicable with DANE-TA(2)
2426 if (depth >= ctx->num_untrusted)
2427 mask &= DANETLS_PKIX_MASK;
2430 * If we've previously matched a PKIX-?? record, no need to test any
2431 * further PKIX-?? records, it remains to just build the PKIX chain.
2432 * Had the match been a DANE-?? record, we'd be done already.
2434 if (dane->mdpth >= 0)
2435 mask &= ~DANETLS_PKIX_MASK;
2438 * https://tools.ietf.org/html/rfc7671#section-5.1
2439 * https://tools.ietf.org/html/rfc7671#section-5.2
2440 * https://tools.ietf.org/html/rfc7671#section-5.3
2441 * https://tools.ietf.org/html/rfc7671#section-5.4
2443 * We handle DANE-EE(3) records first as they require no chain building
2444 * and no expiration or hostname checks. We also process digests with
2445 * higher ordinals first and ignore lower priorities except Full(0) which
2446 * is always processed (last). If none match, we then process PKIX-EE(1).
2448 * NOTE: This relies on DANE usages sorting before the corresponding PKIX
2449 * usages in SSL_dane_tlsa_add(), and also on descending sorting of digest
2450 * priorities. See twin comment in ssl/ssl_lib.c.
2452 * We expect that most TLSA RRsets will have just a single usage, so we
2453 * don't go out of our way to cache multiple selector-specific i2d buffers
2454 * across usages, but if the selector happens to remain the same as switch
2455 * usages, that's OK. Thus, a set of "3 1 1", "3 0 1", "1 1 1", "1 0 1",
2456 * records would result in us generating each of the certificate and public
2457 * key DER forms twice, but more typically we'd just see multiple "3 1 1"
2458 * or multiple "3 0 1" records.
2460 * As soon as we find a match at any given depth, we stop, because either
2461 * we've matched a DANE-?? record and the peer is authenticated, or, after
2462 * exhausting all DANE-?? records, we've matched a PKIX-?? record, which is
2463 * sufficient for DANE, and what remains to do is ordinary PKIX validation.
2465 recnum = (dane->umask & mask) ? sk_danetls_record_num(dane->trecs) : 0;
2466 for (i = 0; matched == 0 && i < recnum; ++i) {
2467 t = sk_danetls_record_value(dane->trecs, i);
2468 if ((DANETLS_USAGE_BIT(t->usage) & mask) == 0)
2470 if (t->usage != usage) {
2473 /* Reset digest agility for each usage/selector pair */
2474 mtype = DANETLS_NONE;
2475 ordinal = dane->dctx->mdord[t->mtype];
2477 if (t->selector != selector) {
2478 selector = t->selector;
2480 /* Update per-selector state */
2481 OPENSSL_free(i2dbuf);
2482 i2dbuf = dane_i2d(cert, selector, &i2dlen);
2486 /* Reset digest agility for each usage/selector pair */
2487 mtype = DANETLS_NONE;
2488 ordinal = dane->dctx->mdord[t->mtype];
2489 } else if (t->mtype != DANETLS_MATCHING_FULL) {
2493 * <https://tools.ietf.org/html/rfc7671#section-9>
2495 * For a fixed selector, after processing all records with the
2496 * highest mtype ordinal, ignore all mtypes with lower ordinals
2497 * other than "Full".
2499 if (dane->dctx->mdord[t->mtype] < ordinal)
2504 * Each time we hit a (new selector or) mtype, re-compute the relevant
2505 * digest, more complex caching is not worth the code space.
2507 if (t->mtype != mtype) {
2508 const EVP_MD *md = dane->dctx->mdevp[mtype = t->mtype];
2514 if (!EVP_Digest(i2dbuf, i2dlen, cmpbuf, &cmplen, md, 0)) {
2522 * Squirrel away the certificate and depth if we have a match. Any
2523 * DANE match is dispositive, but with PKIX we still need to build a
2526 if (cmplen == t->dlen &&
2527 memcmp(cmpbuf, t->data, cmplen) == 0) {
2528 if (DANETLS_USAGE_BIT(usage) & DANETLS_DANE_MASK)
2530 if (matched || dane->mdpth < 0) {
2531 dane->mdpth = depth;
2533 OPENSSL_free(dane->mcert);
2541 /* Clear the one-element DER cache */
2542 OPENSSL_free(i2dbuf);
2546 static int check_dane_issuer(X509_STORE_CTX *ctx, int depth)
2548 SSL_DANE *dane = ctx->dane;
2552 if (!DANETLS_HAS_TA(dane) || depth == 0)
2553 return X509_TRUST_UNTRUSTED;
2556 * Record any DANE trust-anchor matches, for the first depth to test, if
2557 * there's one at that depth. (This'll be false for length 1 chains looking
2558 * for an exact match for the leaf certificate).
2560 cert = sk_X509_value(ctx->chain, depth);
2561 if (cert != NULL && (matched = dane_match(ctx, cert, depth)) < 0)
2562 return X509_TRUST_REJECTED;
2564 ctx->num_untrusted = depth - 1;
2565 return X509_TRUST_TRUSTED;
2568 return X509_TRUST_UNTRUSTED;
2571 static int check_dane_pkeys(X509_STORE_CTX *ctx)
2573 SSL_DANE *dane = ctx->dane;
2575 int num = ctx->num_untrusted;
2576 X509 *cert = sk_X509_value(ctx->chain, num - 1);
2577 int recnum = sk_danetls_record_num(dane->trecs);
2580 for (i = 0; i < recnum; ++i) {
2581 t = sk_danetls_record_value(dane->trecs, i);
2582 if (t->usage != DANETLS_USAGE_DANE_TA ||
2583 t->selector != DANETLS_SELECTOR_SPKI ||
2584 t->mtype != DANETLS_MATCHING_FULL ||
2585 X509_verify(cert, t->spki) <= 0)
2588 /* Clear any PKIX-?? matches that failed to extend to a full chain */
2589 X509_free(dane->mcert);
2592 /* Record match via a bare TA public key */
2593 ctx->bare_ta_signed = 1;
2594 dane->mdpth = num - 1;
2597 /* Prune any excess chain certificates */
2598 num = sk_X509_num(ctx->chain);
2599 for (; num > ctx->num_untrusted; --num)
2600 X509_free(sk_X509_pop(ctx->chain));
2602 return X509_TRUST_TRUSTED;
2605 return X509_TRUST_UNTRUSTED;
2608 static void dane_reset(SSL_DANE *dane)
2611 * Reset state to verify another chain, or clear after failure.
2613 X509_free(dane->mcert);
2620 static int check_leaf_suiteb(X509_STORE_CTX *ctx, X509 *cert)
2622 int err = X509_chain_check_suiteb(NULL, cert, NULL, ctx->param->flags);
2624 if (err == X509_V_OK)
2626 return verify_cb_cert(ctx, cert, 0, err);
2629 static int dane_verify(X509_STORE_CTX *ctx)
2631 X509 *cert = ctx->cert;
2632 SSL_DANE *dane = ctx->dane;
2639 * When testing the leaf certificate, if we match a DANE-EE(3) record,
2640 * dane_match() returns 1 and we're done. If however we match a PKIX-EE(1)
2641 * record, the match depth and matching TLSA record are recorded, but the
2642 * return value is 0, because we still need to find a PKIX trust-anchor.
2643 * Therefore, when DANE authentication is enabled (required), we're done
2645 * + matched < 0, internal error.
2646 * + matched == 1, we matched a DANE-EE(3) record
2647 * + matched == 0, mdepth < 0 (no PKIX-EE match) and there are no
2648 * DANE-TA(2) or PKIX-TA(0) to test.
2650 matched = dane_match(ctx, ctx->cert, 0);
2651 done = matched != 0 || (!DANETLS_HAS_TA(dane) && dane->mdpth < 0);
2654 X509_get_pubkey_parameters(NULL, ctx->chain);
2657 /* Callback invoked as needed */
2658 if (!check_leaf_suiteb(ctx, cert))
2660 /* Bypass internal_verify(), issue depth 0 success callback */
2661 ctx->error_depth = 0;
2662 ctx->current_cert = cert;
2663 return ctx->verify_cb(1, ctx);
2667 ctx->error_depth = 0;
2668 ctx->current_cert = cert;
2669 ctx->error = X509_V_ERR_OUT_OF_MEM;
2674 /* Fail early, TA-based success is not possible */
2675 if (!check_leaf_suiteb(ctx, cert))
2677 return verify_cb_cert(ctx, cert, 0, X509_V_ERR_DANE_NO_MATCH);
2681 * Chain verification for usages 0/1/2. TLSA record matching of depth > 0
2682 * certificates happens in-line with building the rest of the chain.
2684 return verify_chain(ctx);
2687 /* Get issuer, without duplicate suppression */
2688 static int get_issuer(X509 **issuer, X509_STORE_CTX *ctx, X509 *cert)
2690 STACK_OF(X509) *saved_chain = ctx->chain;
2694 ok = ctx->get_issuer(issuer, ctx, cert);
2695 ctx->chain = saved_chain;
2700 static int build_chain(X509_STORE_CTX *ctx)
2702 SSL_DANE *dane = ctx->dane;
2703 int num = sk_X509_num(ctx->chain);
2704 X509 *cert = sk_X509_value(ctx->chain, num - 1);
2705 int ss = cert_self_signed(cert);
2706 STACK_OF(X509) *sktmp = NULL;
2707 unsigned int search;
2708 int may_trusted = 0;
2709 int may_alternate = 0;
2710 int trust = X509_TRUST_UNTRUSTED;
2711 int alt_untrusted = 0;
2716 /* Our chain starts with a single untrusted element. */
2717 OPENSSL_assert(num == 1 && ctx->num_untrusted == num);
2719 #define S_DOUNTRUSTED (1 << 0) /* Search untrusted chain */
2720 #define S_DOTRUSTED (1 << 1) /* Search trusted store */
2721 #define S_DOALTERNATE (1 << 2) /* Retry with pruned alternate chain */
2723 * Set up search policy, untrusted if possible, trusted-first if enabled.
2724 * If we're doing DANE and not doing PKIX-TA/PKIX-EE, we never look in the
2725 * trust_store, otherwise we might look there first. If not trusted-first,
2726 * and alternate chains are not disabled, try building an alternate chain
2727 * if no luck with untrusted first.
2729 search = (ctx->untrusted != NULL) ? S_DOUNTRUSTED : 0;
2730 if (DANETLS_HAS_PKIX(dane) || !DANETLS_HAS_DANE(dane)) {
2731 if (search == 0 || ctx->param->flags & X509_V_FLAG_TRUSTED_FIRST)
2732 search |= S_DOTRUSTED;
2733 else if (!(ctx->param->flags & X509_V_FLAG_NO_ALT_CHAINS))
2739 * Shallow-copy the stack of untrusted certificates (with TLS, this is
2740 * typically the content of the peer's certificate message) so can make
2741 * multiple passes over it, while free to remove elements as we go.
2743 if (ctx->untrusted && (sktmp = sk_X509_dup(ctx->untrusted)) == NULL) {
2744 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2749 * If we got any "DANE-TA(2) Cert(0) Full(0)" trust-anchors from DNS, add
2750 * them to our working copy of the untrusted certificate stack. Since the
2751 * caller of X509_STORE_CTX_init() may have provided only a leaf cert with
2752 * no corresponding stack of untrusted certificates, we may need to create
2753 * an empty stack first. [ At present only the ssl library provides DANE
2754 * support, and ssl_verify_cert_chain() always provides a non-null stack
2755 * containing at least the leaf certificate, but we must be prepared for
2758 if (DANETLS_ENABLED(dane) && dane->certs != NULL) {
2759 if (sktmp == NULL && (sktmp = sk_X509_new_null()) == NULL) {
2760 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2763 for (i = 0; i < sk_X509_num(dane->certs); ++i) {
2764 if (!sk_X509_push(sktmp, sk_X509_value(dane->certs, i))) {
2765 sk_X509_free(sktmp);
2766 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2773 * Still absurdly large, but arithmetically safe, a lower hard upper bound
2774 * might be reasonable.
2776 if (ctx->param->depth > INT_MAX/2)
2777 ctx->param->depth = INT_MAX/2;
2780 * Try to Extend the chain until we reach an ultimately trusted issuer.
2781 * Build chains up to one longer the limit, later fail if we hit the limit,
2782 * with an X509_V_ERR_CERT_CHAIN_TOO_LONG error code.
2784 depth = ctx->param->depth + 1;
2786 while (search != 0) {
2791 * Look in the trust store if enabled for first lookup, or we've run
2792 * out of untrusted issuers and search here is not disabled. When we
2793 * reach the depth limit, we stop extending the chain, if by that point
2794 * we've not found a trust-anchor, any trusted chain would be too long.
2796 * The error reported to the application verify callback is at the
2797 * maximal valid depth with the current certificate equal to the last
2798 * not ultimately-trusted issuer. For example, with verify_depth = 0,
2799 * the callback will report errors at depth=1 when the immediate issuer
2800 * of the leaf certificate is not a trust anchor. No attempt will be
2801 * made to locate an issuer for that certificate, since such a chain
2802 * would be a-priori too long.
2804 if ((search & S_DOTRUSTED) != 0) {
2805 i = num = sk_X509_num(ctx->chain);
2806 if ((search & S_DOALTERNATE) != 0) {
2808 * As high up the chain as we can, look for an alternative
2809 * trusted issuer of an untrusted certificate that currently
2810 * has an untrusted issuer. We use the alt_untrusted variable
2811 * to track how far up the chain we find the first match. It
2812 * is only if and when we find a match, that we prune the chain
2813 * and reset ctx->num_untrusted to the reduced count of
2814 * untrusted certificates. While we're searching for such a
2815 * match (which may never be found), it is neither safe nor
2816 * wise to preemptively modify either the chain or
2817 * ctx->num_untrusted.
2819 * Note, like ctx->num_untrusted, alt_untrusted is a count of
2820 * untrusted certificates, not a "depth".
2824 x = sk_X509_value(ctx->chain, i-1);
2826 ok = (depth < num) ? 0 : get_issuer(&xtmp, ctx, x);
2829 trust = X509_TRUST_REJECTED;
2836 * Alternative trusted issuer for a mid-chain untrusted cert?
2837 * Pop the untrusted cert's successors and retry. We might now
2838 * be able to complete a valid chain via the trust store. Note
2839 * that despite the current trust-store match we might still
2840 * fail complete the chain to a suitable trust-anchor, in which
2841 * case we may prune some more untrusted certificates and try
2842 * again. Thus the S_DOALTERNATE bit may yet be turned on
2843 * again with an even shorter untrusted chain!
2845 * If in the process we threw away our matching PKIX-TA trust
2846 * anchor, reset DANE trust. We might find a suitable trusted
2847 * certificate among the ones from the trust store.
2849 if ((search & S_DOALTERNATE) != 0) {
2850 OPENSSL_assert(num > i && i > 0 && ss == 0);
2851 search &= ~S_DOALTERNATE;
2852 for (; num > i; --num)
2853 X509_free(sk_X509_pop(ctx->chain));
2854 ctx->num_untrusted = num;
2856 if (DANETLS_ENABLED(dane) &&
2857 dane->mdpth >= ctx->num_untrusted) {
2859 X509_free(dane->mcert);
2862 if (DANETLS_ENABLED(dane) &&
2863 dane->pdpth >= ctx->num_untrusted)
2868 * Self-signed untrusted certificates get replaced by their
2869 * trusted matching issuer. Otherwise, grow the chain.
2872 if (!sk_X509_push(ctx->chain, x = xtmp)) {
2874 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2875 trust = X509_TRUST_REJECTED;
2879 ss = cert_self_signed(x);
2880 } else if (num == ctx->num_untrusted) {
2882 * We have a self-signed certificate that has the same
2883 * subject name (and perhaps keyid and/or serial number) as
2884 * a trust-anchor. We must have an exact match to avoid
2885 * possible impersonation via key substitution etc.
2887 if (X509_cmp(x, xtmp) != 0) {
2888 /* Self-signed untrusted mimic. */
2893 ctx->num_untrusted = --num;
2894 (void) sk_X509_set(ctx->chain, num, x = xtmp);
2899 * We've added a new trusted certificate to the chain, recheck
2900 * trust. If not done, and not self-signed look deeper.
2901 * Whether or not we're doing "trusted first", we no longer
2902 * look for untrusted certificates from the peer's chain.
2904 * At this point ctx->num_trusted and num must reflect the
2905 * correct number of untrusted certificates, since the DANE
2906 * logic in check_trust() depends on distinguishing CAs from
2907 * "the wire" from CAs from the trust store. In particular, the
2908 * certificate at depth "num" should be the new trusted
2909 * certificate with ctx->num_untrusted <= num.
2912 OPENSSL_assert(ctx->num_untrusted <= num);
2913 search &= ~S_DOUNTRUSTED;
2914 switch (trust = check_trust(ctx, num)) {
2915 case X509_TRUST_TRUSTED:
2916 case X509_TRUST_REJECTED:
2926 * No dispositive decision, and either self-signed or no match, if
2927 * we were doing untrusted-first, and alt-chains are not disabled,
2928 * do that, by repeatedly losing one untrusted element at a time,
2929 * and trying to extend the shorted chain.
2931 if ((search & S_DOUNTRUSTED) == 0) {
2932 /* Continue search for a trusted issuer of a shorter chain? */
2933 if ((search & S_DOALTERNATE) != 0 && --alt_untrusted > 0)
2935 /* Still no luck and no fallbacks left? */
2936 if (!may_alternate || (search & S_DOALTERNATE) != 0 ||
2937 ctx->num_untrusted < 2)
2939 /* Search for a trusted issuer of a shorter chain */
2940 search |= S_DOALTERNATE;
2941 alt_untrusted = ctx->num_untrusted - 1;
2947 * Extend chain with peer-provided certificates
2949 if ((search & S_DOUNTRUSTED) != 0) {
2950 num = sk_X509_num(ctx->chain);
2951 OPENSSL_assert(num == ctx->num_untrusted);
2952 x = sk_X509_value(ctx->chain, num-1);
2955 * Once we run out of untrusted issuers, we stop looking for more
2956 * and start looking only in the trust store if enabled.
2958 xtmp = (ss || depth < num) ? NULL : find_issuer(ctx, sktmp, x);
2960 search &= ~S_DOUNTRUSTED;
2962 search |= S_DOTRUSTED;
2966 /* Drop this issuer from future consideration */
2967 (void) sk_X509_delete_ptr(sktmp, xtmp);
2969 if (!sk_X509_push(ctx->chain, xtmp)) {
2970 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2971 trust = X509_TRUST_REJECTED;
2976 X509_up_ref(x = xtmp);
2977 ++ctx->num_untrusted;
2978 ss = cert_self_signed(xtmp);
2981 * Check for DANE-TA trust of the topmost untrusted certificate.
2983 switch (trust = check_dane_issuer(ctx, ctx->num_untrusted - 1)) {
2984 case X509_TRUST_TRUSTED:
2985 case X509_TRUST_REJECTED:
2991 sk_X509_free(sktmp);
2994 * Last chance to make a trusted chain, either bare DANE-TA public-key
2995 * signers, or else direct leaf PKIX trust.
2997 num = sk_X509_num(ctx->chain);
2999 if (trust == X509_TRUST_UNTRUSTED && DANETLS_HAS_DANE_TA(dane))
3000 trust = check_dane_pkeys(ctx);
3001 if (trust == X509_TRUST_UNTRUSTED && num == ctx->num_untrusted)
3002 trust = check_trust(ctx, num);
3006 case X509_TRUST_TRUSTED:
3008 case X509_TRUST_REJECTED:
3009 /* Callback already issued */
3011 case X509_TRUST_UNTRUSTED:
3013 num = sk_X509_num(ctx->chain);
3015 return verify_cb_cert(ctx, NULL, num-1,
3016 X509_V_ERR_CERT_CHAIN_TOO_LONG);
3017 if (DANETLS_ENABLED(dane) &&
3018 (!DANETLS_HAS_PKIX(dane) || dane->pdpth >= 0))
3019 return verify_cb_cert(ctx, NULL, num-1, X509_V_ERR_DANE_NO_MATCH);
3020 if (ss && sk_X509_num(ctx->chain) == 1)
3021 return verify_cb_cert(ctx, NULL, num-1,
3022 X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT);
3024 return verify_cb_cert(ctx, NULL, num-1,
3025 X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN);
3026 if (ctx->num_untrusted < num)
3027 return verify_cb_cert(ctx, NULL, num-1,
3028 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT);
3029 return verify_cb_cert(ctx, NULL, num-1,
3030 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY);
3034 static const int minbits_table[] = { 80, 112, 128, 192, 256 };
3035 static const int NUM_AUTH_LEVELS = OSSL_NELEM(minbits_table);
3038 * Check whether the public key of ``cert`` meets the security level of
3041 * Returns 1 on success, 0 otherwise.
3043 static int check_key_level(X509_STORE_CTX *ctx, X509 *cert)
3045 EVP_PKEY *pkey = X509_get0_pubkey(cert);
3046 int level = ctx->param->auth_level;
3048 /* Unsupported or malformed keys are not secure */
3054 if (level > NUM_AUTH_LEVELS)
3055 level = NUM_AUTH_LEVELS;
3057 return EVP_PKEY_security_bits(pkey) >= minbits_table[level - 1];
3061 * Check whether the signature digest algorithm of ``cert`` meets the security
3062 * level of ``ctx``. Should not be checked for trust anchors (whether
3063 * self-signed or otherwise).
3065 * Returns 1 on success, 0 otherwise.
3067 static int check_sig_level(X509_STORE_CTX *ctx, X509 *cert)
3069 int nid = X509_get_signature_nid(cert);
3070 int mdnid = NID_undef;
3072 int level = ctx->param->auth_level;
3076 if (level > NUM_AUTH_LEVELS)
3077 level = NUM_AUTH_LEVELS;
3079 /* Lookup signature algorithm digest */
3080 if (nid && OBJ_find_sigid_algs(nid, &mdnid, NULL)) {
3083 /* Assume 4 bits of collision resistance for each hash octet */
3084 if (mdnid != NID_undef && (md = EVP_get_digestbynid(mdnid)) != NULL)
3085 secbits = EVP_MD_size(md) * 4;
3088 return secbits >= minbits_table[level - 1];