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;
256 if (ctx->cert == NULL) {
257 X509err(X509_F_X509_VERIFY_CERT, X509_R_NO_CERT_SET_FOR_US_TO_VERIFY);
258 ctx->error = X509_V_ERR_INVALID_CALL;
262 if (ctx->chain != NULL) {
264 * This X509_STORE_CTX has already been used to verify a cert. We
265 * cannot do another one.
267 X509err(X509_F_X509_VERIFY_CERT, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
268 ctx->error = X509_V_ERR_INVALID_CALL;
273 * first we make sure the chain we are going to build is present and that
274 * the first entry is in place
276 if (((ctx->chain = sk_X509_new_null()) == NULL) ||
277 (!sk_X509_push(ctx->chain, ctx->cert))) {
278 X509err(X509_F_X509_VERIFY_CERT, ERR_R_MALLOC_FAILURE);
279 ctx->error = X509_V_ERR_OUT_OF_MEM;
282 X509_up_ref(ctx->cert);
283 ctx->num_untrusted = 1;
285 /* If the peer's public key is too weak, we can stop early. */
286 if (!check_key_level(ctx, ctx->cert) &&
287 !verify_cb_cert(ctx, ctx->cert, 0, X509_V_ERR_EE_KEY_TOO_SMALL))
290 if (DANETLS_ENABLED(dane))
291 ret = dane_verify(ctx);
293 ret = verify_chain(ctx);
296 * Safety-net. If we are returning an error, we must also set ctx->error,
297 * so that the chain is not considered verified should the error be ignored
298 * (e.g. TLS with SSL_VERIFY_NONE).
300 if (ret <= 0 && ctx->error == X509_V_OK)
301 ctx->error = X509_V_ERR_UNSPECIFIED;
306 * Given a STACK_OF(X509) find the issuer of cert (if any)
308 static X509 *find_issuer(X509_STORE_CTX *ctx, STACK_OF(X509) *sk, X509 *x)
312 for (i = 0; i < sk_X509_num(sk); i++) {
313 X509 *issuer = sk_X509_value(sk, i);
315 if (!ctx->check_issued(ctx, x, issuer))
317 if (x509_check_cert_time(ctx, issuer, -1))
323 /* Given a possible certificate and issuer check them */
325 static int check_issued(X509_STORE_CTX *ctx, X509 *x, X509 *issuer)
329 return cert_self_signed(x);
330 ret = X509_check_issued(issuer, x);
331 if (ret == X509_V_OK) {
334 /* Special case: single self signed certificate */
335 if (cert_self_signed(x) && sk_X509_num(ctx->chain) == 1)
337 for (i = 0; i < sk_X509_num(ctx->chain); i++) {
338 ch = sk_X509_value(ctx->chain, i);
339 if (ch == issuer || !X509_cmp(ch, issuer)) {
340 ret = X509_V_ERR_PATH_LOOP;
346 return (ret == X509_V_OK);
349 /* Alternative lookup method: look from a STACK stored in other_ctx */
351 static int get_issuer_sk(X509 **issuer, X509_STORE_CTX *ctx, X509 *x)
353 *issuer = find_issuer(ctx, ctx->other_ctx, x);
355 X509_up_ref(*issuer);
361 static STACK_OF(X509) *lookup_certs_sk(X509_STORE_CTX *ctx, X509_NAME *nm)
363 STACK_OF(X509) *sk = NULL;
366 for (i = 0; i < sk_X509_num(ctx->other_ctx); i++) {
367 x = sk_X509_value(ctx->other_ctx, i);
368 if (X509_NAME_cmp(nm, X509_get_subject_name(x)) == 0) {
370 sk = sk_X509_new_null();
371 if (sk == NULL || sk_X509_push(sk, x) == 0) {
372 sk_X509_pop_free(sk, X509_free);
382 * Check EE or CA certificate purpose. For trusted certificates explicit local
383 * auxiliary trust can be used to override EKU-restrictions.
385 static int check_purpose(X509_STORE_CTX *ctx, X509 *x, int purpose, int depth,
388 int tr_ok = X509_TRUST_UNTRUSTED;
391 * For trusted certificates we want to see whether any auxiliary trust
392 * settings trump the purpose constraints.
394 * This is complicated by the fact that the trust ordinals in
395 * ctx->param->trust are entirely independent of the purpose ordinals in
396 * ctx->param->purpose!
398 * What connects them is their mutual initialization via calls from
399 * X509_STORE_CTX_set_default() into X509_VERIFY_PARAM_lookup() which sets
400 * related values of both param->trust and param->purpose. It is however
401 * typically possible to infer associated trust values from a purpose value
402 * via the X509_PURPOSE API.
404 * Therefore, we can only check for trust overrides when the purpose we're
405 * checking is the same as ctx->param->purpose and ctx->param->trust is
408 if (depth >= ctx->num_untrusted && purpose == ctx->param->purpose)
409 tr_ok = X509_check_trust(x, ctx->param->trust, X509_TRUST_NO_SS_COMPAT);
412 case X509_TRUST_TRUSTED:
414 case X509_TRUST_REJECTED:
417 switch (X509_check_purpose(x, purpose, must_be_ca > 0)) {
423 if ((ctx->param->flags & X509_V_FLAG_X509_STRICT) == 0)
429 return verify_cb_cert(ctx, x, depth, X509_V_ERR_INVALID_PURPOSE);
433 * Check a certificate chains extensions for consistency with the supplied
437 static int check_chain_extensions(X509_STORE_CTX *ctx)
439 int i, must_be_ca, plen = 0;
441 int proxy_path_length = 0;
443 int allow_proxy_certs;
444 int num = sk_X509_num(ctx->chain);
447 * must_be_ca can have 1 of 3 values:
448 * -1: we accept both CA and non-CA certificates, to allow direct
449 * use of self-signed certificates (which are marked as CA).
450 * 0: we only accept non-CA certificates. This is currently not
451 * used, but the possibility is present for future extensions.
452 * 1: we only accept CA certificates. This is currently used for
453 * all certificates in the chain except the leaf certificate.
457 /* CRL path validation */
459 allow_proxy_certs = 0;
460 purpose = X509_PURPOSE_CRL_SIGN;
463 ! !(ctx->param->flags & X509_V_FLAG_ALLOW_PROXY_CERTS);
465 * A hack to keep people who don't want to modify their software
468 if (getenv("OPENSSL_ALLOW_PROXY_CERTS"))
469 allow_proxy_certs = 1;
470 purpose = ctx->param->purpose;
473 for (i = 0; i < num; i++) {
475 x = sk_X509_value(ctx->chain, i);
476 if (!(ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL)
477 && (x->ex_flags & EXFLAG_CRITICAL)) {
478 if (!verify_cb_cert(ctx, x, i,
479 X509_V_ERR_UNHANDLED_CRITICAL_EXTENSION))
482 if (!allow_proxy_certs && (x->ex_flags & EXFLAG_PROXY)) {
483 if (!verify_cb_cert(ctx, x, i,
484 X509_V_ERR_PROXY_CERTIFICATES_NOT_ALLOWED))
487 ret = X509_check_ca(x);
488 switch (must_be_ca) {
490 if ((ctx->param->flags & X509_V_FLAG_X509_STRICT)
491 && (ret != 1) && (ret != 0)) {
493 ctx->error = X509_V_ERR_INVALID_CA;
500 ctx->error = X509_V_ERR_INVALID_NON_CA;
505 /* X509_V_FLAG_X509_STRICT is implicit for intermediate CAs */
507 || ((i + 1 < num || ctx->param->flags & X509_V_FLAG_X509_STRICT)
510 ctx->error = X509_V_ERR_INVALID_CA;
515 if (ret == 0 && !verify_cb_cert(ctx, x, i, X509_V_OK))
517 /* check_purpose() makes the callback as needed */
518 if (purpose > 0 && !check_purpose(ctx, x, purpose, i, must_be_ca))
520 /* Check pathlen if not self issued */
521 if ((i > 1) && !(x->ex_flags & EXFLAG_SI)
522 && (x->ex_pathlen != -1)
523 && (plen > (x->ex_pathlen + proxy_path_length + 1))) {
524 if (!verify_cb_cert(ctx, x, i, X509_V_ERR_PATH_LENGTH_EXCEEDED))
527 /* Increment path length if not self issued */
528 if (!(x->ex_flags & EXFLAG_SI))
531 * If this certificate is a proxy certificate, the next certificate
532 * must be another proxy certificate or a EE certificate. If not,
533 * the next certificate must be a CA certificate.
535 if (x->ex_flags & EXFLAG_PROXY) {
536 if (x->ex_pcpathlen != -1 && i > x->ex_pcpathlen) {
537 if (!verify_cb_cert(ctx, x, i,
538 X509_V_ERR_PROXY_PATH_LENGTH_EXCEEDED))
549 static int check_name_constraints(X509_STORE_CTX *ctx)
553 /* Check name constraints for all certificates */
554 for (i = sk_X509_num(ctx->chain) - 1; i >= 0; i--) {
555 X509 *x = sk_X509_value(ctx->chain, i);
558 /* Ignore self issued certs unless last in chain */
559 if (i && (x->ex_flags & EXFLAG_SI))
562 * Check against constraints for all certificates higher in chain
563 * including trust anchor. Trust anchor not strictly speaking needed
564 * but if it includes constraints it is to be assumed it expects them
567 for (j = sk_X509_num(ctx->chain) - 1; j > i; j--) {
568 NAME_CONSTRAINTS *nc = sk_X509_value(ctx->chain, j)->nc;
571 int rv = NAME_CONSTRAINTS_check(x, nc);
576 case X509_V_ERR_OUT_OF_MEM:
579 if (!verify_cb_cert(ctx, x, i, rv))
589 static int check_id_error(X509_STORE_CTX *ctx, int errcode)
591 return verify_cb_cert(ctx, ctx->cert, 0, errcode);
594 static int check_hosts(X509 *x, X509_VERIFY_PARAM *vpm)
597 int n = sk_OPENSSL_STRING_num(vpm->hosts);
600 if (vpm->peername != NULL) {
601 OPENSSL_free(vpm->peername);
602 vpm->peername = NULL;
604 for (i = 0; i < n; ++i) {
605 name = sk_OPENSSL_STRING_value(vpm->hosts, i);
606 if (X509_check_host(x, name, 0, vpm->hostflags, &vpm->peername) > 0)
612 static int check_id(X509_STORE_CTX *ctx)
614 X509_VERIFY_PARAM *vpm = ctx->param;
616 if (vpm->hosts && check_hosts(x, vpm) <= 0) {
617 if (!check_id_error(ctx, X509_V_ERR_HOSTNAME_MISMATCH))
620 if (vpm->email && X509_check_email(x, vpm->email, vpm->emaillen, 0) <= 0) {
621 if (!check_id_error(ctx, X509_V_ERR_EMAIL_MISMATCH))
624 if (vpm->ip && X509_check_ip(x, vpm->ip, vpm->iplen, 0) <= 0) {
625 if (!check_id_error(ctx, X509_V_ERR_IP_ADDRESS_MISMATCH))
631 static int check_trust(X509_STORE_CTX *ctx, int num_untrusted)
636 SSL_DANE *dane = ctx->dane;
637 int num = sk_X509_num(ctx->chain);
641 * Check for a DANE issuer at depth 1 or greater, if it is a DANE-TA(2)
642 * match, we're done, otherwise we'll merely record the match depth.
644 if (DANETLS_HAS_TA(dane) && num_untrusted > 0 && num_untrusted < num) {
645 switch (trust = check_dane_issuer(ctx, num_untrusted)) {
646 case X509_TRUST_TRUSTED:
647 case X509_TRUST_REJECTED:
653 * Check trusted certificates in chain at depth num_untrusted and up.
654 * Note, that depths 0..num_untrusted-1 may also contain trusted
655 * certificates, but the caller is expected to have already checked those,
656 * and wants to incrementally check just any added since.
658 for (i = num_untrusted; i < num; i++) {
659 x = sk_X509_value(ctx->chain, i);
660 trust = X509_check_trust(x, ctx->param->trust, 0);
661 /* If explicitly trusted return trusted */
662 if (trust == X509_TRUST_TRUSTED)
664 if (trust == X509_TRUST_REJECTED)
669 * If we are looking at a trusted certificate, and accept partial chains,
670 * the chain is PKIX trusted.
672 if (num_untrusted < num) {
673 if (ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN)
675 return X509_TRUST_UNTRUSTED;
678 if (num_untrusted == num && ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) {
680 * Last-resort call with no new trusted certificates, check the leaf
681 * for a direct trust store match.
684 x = sk_X509_value(ctx->chain, i);
685 mx = lookup_cert_match(ctx, x);
687 return X509_TRUST_UNTRUSTED;
690 * Check explicit auxiliary trust/reject settings. If none are set,
691 * we'll accept X509_TRUST_UNTRUSTED when not self-signed.
693 trust = X509_check_trust(mx, ctx->param->trust, 0);
694 if (trust == X509_TRUST_REJECTED) {
699 /* Replace leaf with trusted match */
700 (void) sk_X509_set(ctx->chain, 0, mx);
702 ctx->num_untrusted = 0;
707 * If no trusted certs in chain at all return untrusted and allow
708 * standard (no issuer cert) etc errors to be indicated.
710 return X509_TRUST_UNTRUSTED;
713 if (!verify_cb_cert(ctx, x, i, X509_V_ERR_CERT_REJECTED))
714 return X509_TRUST_REJECTED;
715 return X509_TRUST_UNTRUSTED;
718 if (!DANETLS_ENABLED(dane))
719 return X509_TRUST_TRUSTED;
721 dane->pdpth = num_untrusted;
722 /* With DANE, PKIX alone is not trusted until we have both */
723 if (dane->mdpth >= 0)
724 return X509_TRUST_TRUSTED;
725 return X509_TRUST_UNTRUSTED;
728 static int check_revocation(X509_STORE_CTX *ctx)
730 int i = 0, last = 0, ok = 0;
731 if (!(ctx->param->flags & X509_V_FLAG_CRL_CHECK))
733 if (ctx->param->flags & X509_V_FLAG_CRL_CHECK_ALL)
734 last = sk_X509_num(ctx->chain) - 1;
736 /* If checking CRL paths this isn't the EE certificate */
741 for (i = 0; i <= last; i++) {
742 ctx->error_depth = i;
743 ok = check_cert(ctx);
750 static int check_cert(X509_STORE_CTX *ctx)
752 X509_CRL *crl = NULL, *dcrl = NULL;
754 int cnum = ctx->error_depth;
755 X509 *x = sk_X509_value(ctx->chain, cnum);
757 ctx->current_cert = x;
758 ctx->current_issuer = NULL;
759 ctx->current_crl_score = 0;
760 ctx->current_reasons = 0;
762 while (ctx->current_reasons != CRLDP_ALL_REASONS) {
763 unsigned int last_reasons = ctx->current_reasons;
765 /* Try to retrieve relevant CRL */
767 ok = ctx->get_crl(ctx, &crl, x);
769 ok = get_crl_delta(ctx, &crl, &dcrl, x);
771 * If error looking up CRL, nothing we can do except notify callback
774 ok = verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL);
777 ctx->current_crl = crl;
778 ok = ctx->check_crl(ctx, crl);
783 ok = ctx->check_crl(ctx, dcrl);
786 ok = ctx->cert_crl(ctx, dcrl, x);
792 /* Don't look in full CRL if delta reason is removefromCRL */
794 ok = ctx->cert_crl(ctx, crl, x);
804 * If reasons not updated we wont get anywhere by another iteration,
807 if (last_reasons == ctx->current_reasons) {
808 ok = verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL);
816 ctx->current_crl = NULL;
820 /* Check CRL times against values in X509_STORE_CTX */
822 static int check_crl_time(X509_STORE_CTX *ctx, X509_CRL *crl, int notify)
828 ctx->current_crl = crl;
829 if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME)
830 ptime = &ctx->param->check_time;
831 else if (ctx->param->flags & X509_V_FLAG_NO_CHECK_TIME)
836 i = X509_cmp_time(X509_CRL_get_lastUpdate(crl), ptime);
840 if (!verify_cb_crl(ctx, X509_V_ERR_ERROR_IN_CRL_LAST_UPDATE_FIELD))
847 if (!verify_cb_crl(ctx, X509_V_ERR_CRL_NOT_YET_VALID))
851 if (X509_CRL_get_nextUpdate(crl)) {
852 i = X509_cmp_time(X509_CRL_get_nextUpdate(crl), ptime);
857 if (!verify_cb_crl(ctx, X509_V_ERR_ERROR_IN_CRL_NEXT_UPDATE_FIELD))
860 /* Ignore expiry of base CRL is delta is valid */
861 if ((i < 0) && !(ctx->current_crl_score & CRL_SCORE_TIME_DELTA)) {
864 if (!verify_cb_crl(ctx, X509_V_ERR_CRL_HAS_EXPIRED))
870 ctx->current_crl = NULL;
875 static int get_crl_sk(X509_STORE_CTX *ctx, X509_CRL **pcrl, X509_CRL **pdcrl,
876 X509 **pissuer, int *pscore, unsigned int *preasons,
877 STACK_OF(X509_CRL) *crls)
879 int i, crl_score, best_score = *pscore;
880 unsigned int reasons, best_reasons = 0;
881 X509 *x = ctx->current_cert;
882 X509_CRL *crl, *best_crl = NULL;
883 X509 *crl_issuer = NULL, *best_crl_issuer = NULL;
885 for (i = 0; i < sk_X509_CRL_num(crls); i++) {
886 crl = sk_X509_CRL_value(crls, i);
888 crl_score = get_crl_score(ctx, &crl_issuer, &reasons, crl, x);
890 if (crl_score > best_score) {
892 best_crl_issuer = crl_issuer;
893 best_score = crl_score;
894 best_reasons = reasons;
899 X509_CRL_free(*pcrl);
901 *pissuer = best_crl_issuer;
902 *pscore = best_score;
903 *preasons = best_reasons;
904 X509_CRL_up_ref(best_crl);
905 X509_CRL_free(*pdcrl);
907 get_delta_sk(ctx, pdcrl, pscore, best_crl, crls);
910 if (best_score >= CRL_SCORE_VALID)
917 * Compare two CRL extensions for delta checking purposes. They should be
918 * both present or both absent. If both present all fields must be identical.
921 static int crl_extension_match(X509_CRL *a, X509_CRL *b, int nid)
923 ASN1_OCTET_STRING *exta, *extb;
925 i = X509_CRL_get_ext_by_NID(a, nid, -1);
927 /* Can't have multiple occurrences */
928 if (X509_CRL_get_ext_by_NID(a, nid, i) != -1)
930 exta = X509_EXTENSION_get_data(X509_CRL_get_ext(a, i));
934 i = X509_CRL_get_ext_by_NID(b, nid, -1);
938 if (X509_CRL_get_ext_by_NID(b, nid, i) != -1)
940 extb = X509_EXTENSION_get_data(X509_CRL_get_ext(b, i));
950 if (ASN1_OCTET_STRING_cmp(exta, extb))
956 /* See if a base and delta are compatible */
958 static int check_delta_base(X509_CRL *delta, X509_CRL *base)
960 /* Delta CRL must be a delta */
961 if (!delta->base_crl_number)
963 /* Base must have a CRL number */
964 if (!base->crl_number)
966 /* Issuer names must match */
967 if (X509_NAME_cmp(X509_CRL_get_issuer(base), X509_CRL_get_issuer(delta)))
969 /* AKID and IDP must match */
970 if (!crl_extension_match(delta, base, NID_authority_key_identifier))
972 if (!crl_extension_match(delta, base, NID_issuing_distribution_point))
974 /* Delta CRL base number must not exceed Full CRL number. */
975 if (ASN1_INTEGER_cmp(delta->base_crl_number, base->crl_number) > 0)
977 /* Delta CRL number must exceed full CRL number */
978 if (ASN1_INTEGER_cmp(delta->crl_number, base->crl_number) > 0)
984 * For a given base CRL find a delta... maybe extend to delta scoring or
985 * retrieve a chain of deltas...
988 static void get_delta_sk(X509_STORE_CTX *ctx, X509_CRL **dcrl, int *pscore,
989 X509_CRL *base, STACK_OF(X509_CRL) *crls)
993 if (!(ctx->param->flags & X509_V_FLAG_USE_DELTAS))
995 if (!((ctx->current_cert->ex_flags | base->flags) & EXFLAG_FRESHEST))
997 for (i = 0; i < sk_X509_CRL_num(crls); i++) {
998 delta = sk_X509_CRL_value(crls, i);
999 if (check_delta_base(delta, base)) {
1000 if (check_crl_time(ctx, delta, 0))
1001 *pscore |= CRL_SCORE_TIME_DELTA;
1002 X509_CRL_up_ref(delta);
1011 * For a given CRL return how suitable it is for the supplied certificate
1012 * 'x'. The return value is a mask of several criteria. If the issuer is not
1013 * the certificate issuer this is returned in *pissuer. The reasons mask is
1014 * also used to determine if the CRL is suitable: if no new reasons the CRL
1015 * is rejected, otherwise reasons is updated.
1018 static int get_crl_score(X509_STORE_CTX *ctx, X509 **pissuer,
1019 unsigned int *preasons, X509_CRL *crl, X509 *x)
1023 unsigned int tmp_reasons = *preasons, crl_reasons;
1025 /* First see if we can reject CRL straight away */
1027 /* Invalid IDP cannot be processed */
1028 if (crl->idp_flags & IDP_INVALID)
1030 /* Reason codes or indirect CRLs need extended CRL support */
1031 if (!(ctx->param->flags & X509_V_FLAG_EXTENDED_CRL_SUPPORT)) {
1032 if (crl->idp_flags & (IDP_INDIRECT | IDP_REASONS))
1034 } else if (crl->idp_flags & IDP_REASONS) {
1035 /* If no new reasons reject */
1036 if (!(crl->idp_reasons & ~tmp_reasons))
1039 /* Don't process deltas at this stage */
1040 else if (crl->base_crl_number)
1042 /* If issuer name doesn't match certificate need indirect CRL */
1043 if (X509_NAME_cmp(X509_get_issuer_name(x), X509_CRL_get_issuer(crl))) {
1044 if (!(crl->idp_flags & IDP_INDIRECT))
1047 crl_score |= CRL_SCORE_ISSUER_NAME;
1049 if (!(crl->flags & EXFLAG_CRITICAL))
1050 crl_score |= CRL_SCORE_NOCRITICAL;
1053 if (check_crl_time(ctx, crl, 0))
1054 crl_score |= CRL_SCORE_TIME;
1056 /* Check authority key ID and locate certificate issuer */
1057 crl_akid_check(ctx, crl, pissuer, &crl_score);
1059 /* If we can't locate certificate issuer at this point forget it */
1061 if (!(crl_score & CRL_SCORE_AKID))
1064 /* Check cert for matching CRL distribution points */
1066 if (crl_crldp_check(x, crl, crl_score, &crl_reasons)) {
1067 /* If no new reasons reject */
1068 if (!(crl_reasons & ~tmp_reasons))
1070 tmp_reasons |= crl_reasons;
1071 crl_score |= CRL_SCORE_SCOPE;
1074 *preasons = tmp_reasons;
1080 static void crl_akid_check(X509_STORE_CTX *ctx, X509_CRL *crl,
1081 X509 **pissuer, int *pcrl_score)
1083 X509 *crl_issuer = NULL;
1084 X509_NAME *cnm = X509_CRL_get_issuer(crl);
1085 int cidx = ctx->error_depth;
1088 if (cidx != sk_X509_num(ctx->chain) - 1)
1091 crl_issuer = sk_X509_value(ctx->chain, cidx);
1093 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1094 if (*pcrl_score & CRL_SCORE_ISSUER_NAME) {
1095 *pcrl_score |= CRL_SCORE_AKID | CRL_SCORE_ISSUER_CERT;
1096 *pissuer = crl_issuer;
1101 for (cidx++; cidx < sk_X509_num(ctx->chain); cidx++) {
1102 crl_issuer = sk_X509_value(ctx->chain, cidx);
1103 if (X509_NAME_cmp(X509_get_subject_name(crl_issuer), cnm))
1105 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1106 *pcrl_score |= CRL_SCORE_AKID | CRL_SCORE_SAME_PATH;
1107 *pissuer = crl_issuer;
1112 /* Anything else needs extended CRL support */
1114 if (!(ctx->param->flags & X509_V_FLAG_EXTENDED_CRL_SUPPORT))
1118 * Otherwise the CRL issuer is not on the path. Look for it in the set of
1119 * untrusted certificates.
1121 for (i = 0; i < sk_X509_num(ctx->untrusted); i++) {
1122 crl_issuer = sk_X509_value(ctx->untrusted, i);
1123 if (X509_NAME_cmp(X509_get_subject_name(crl_issuer), cnm))
1125 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1126 *pissuer = crl_issuer;
1127 *pcrl_score |= CRL_SCORE_AKID;
1134 * Check the path of a CRL issuer certificate. This creates a new
1135 * X509_STORE_CTX and populates it with most of the parameters from the
1136 * parent. This could be optimised somewhat since a lot of path checking will
1137 * be duplicated by the parent, but this will rarely be used in practice.
1140 static int check_crl_path(X509_STORE_CTX *ctx, X509 *x)
1142 X509_STORE_CTX crl_ctx;
1145 /* Don't allow recursive CRL path validation */
1148 if (!X509_STORE_CTX_init(&crl_ctx, ctx->ctx, x, ctx->untrusted))
1151 crl_ctx.crls = ctx->crls;
1152 /* Copy verify params across */
1153 X509_STORE_CTX_set0_param(&crl_ctx, ctx->param);
1155 crl_ctx.parent = ctx;
1156 crl_ctx.verify_cb = ctx->verify_cb;
1158 /* Verify CRL issuer */
1159 ret = X509_verify_cert(&crl_ctx);
1163 /* Check chain is acceptable */
1164 ret = check_crl_chain(ctx, ctx->chain, crl_ctx.chain);
1166 X509_STORE_CTX_cleanup(&crl_ctx);
1171 * RFC3280 says nothing about the relationship between CRL path and
1172 * certificate path, which could lead to situations where a certificate could
1173 * be revoked or validated by a CA not authorised to do so. RFC5280 is more
1174 * strict and states that the two paths must end in the same trust anchor,
1175 * though some discussions remain... until this is resolved we use the
1179 static int check_crl_chain(X509_STORE_CTX *ctx,
1180 STACK_OF(X509) *cert_path,
1181 STACK_OF(X509) *crl_path)
1183 X509 *cert_ta, *crl_ta;
1184 cert_ta = sk_X509_value(cert_path, sk_X509_num(cert_path) - 1);
1185 crl_ta = sk_X509_value(crl_path, sk_X509_num(crl_path) - 1);
1186 if (!X509_cmp(cert_ta, crl_ta))
1192 * Check for match between two dist point names: three separate cases.
1193 * 1. Both are relative names and compare X509_NAME types.
1194 * 2. One full, one relative. Compare X509_NAME to GENERAL_NAMES.
1195 * 3. Both are full names and compare two GENERAL_NAMES.
1196 * 4. One is NULL: automatic match.
1199 static int idp_check_dp(DIST_POINT_NAME *a, DIST_POINT_NAME *b)
1201 X509_NAME *nm = NULL;
1202 GENERAL_NAMES *gens = NULL;
1203 GENERAL_NAME *gena, *genb;
1210 /* Case 1: two X509_NAME */
1214 if (!X509_NAME_cmp(a->dpname, b->dpname))
1219 /* Case 2: set name and GENERAL_NAMES appropriately */
1221 gens = b->name.fullname;
1222 } else if (b->type == 1) {
1225 /* Case 2: set name and GENERAL_NAMES appropriately */
1226 gens = a->name.fullname;
1230 /* Handle case 2 with one GENERAL_NAMES and one X509_NAME */
1232 for (i = 0; i < sk_GENERAL_NAME_num(gens); i++) {
1233 gena = sk_GENERAL_NAME_value(gens, i);
1234 if (gena->type != GEN_DIRNAME)
1236 if (!X509_NAME_cmp(nm, gena->d.directoryName))
1242 /* Else case 3: two GENERAL_NAMES */
1244 for (i = 0; i < sk_GENERAL_NAME_num(a->name.fullname); i++) {
1245 gena = sk_GENERAL_NAME_value(a->name.fullname, i);
1246 for (j = 0; j < sk_GENERAL_NAME_num(b->name.fullname); j++) {
1247 genb = sk_GENERAL_NAME_value(b->name.fullname, j);
1248 if (!GENERAL_NAME_cmp(gena, genb))
1257 static int crldp_check_crlissuer(DIST_POINT *dp, X509_CRL *crl, int crl_score)
1260 X509_NAME *nm = X509_CRL_get_issuer(crl);
1261 /* If no CRLissuer return is successful iff don't need a match */
1263 return ! !(crl_score & CRL_SCORE_ISSUER_NAME);
1264 for (i = 0; i < sk_GENERAL_NAME_num(dp->CRLissuer); i++) {
1265 GENERAL_NAME *gen = sk_GENERAL_NAME_value(dp->CRLissuer, i);
1266 if (gen->type != GEN_DIRNAME)
1268 if (!X509_NAME_cmp(gen->d.directoryName, nm))
1274 /* Check CRLDP and IDP */
1276 static int crl_crldp_check(X509 *x, X509_CRL *crl, int crl_score,
1277 unsigned int *preasons)
1280 if (crl->idp_flags & IDP_ONLYATTR)
1282 if (x->ex_flags & EXFLAG_CA) {
1283 if (crl->idp_flags & IDP_ONLYUSER)
1286 if (crl->idp_flags & IDP_ONLYCA)
1289 *preasons = crl->idp_reasons;
1290 for (i = 0; i < sk_DIST_POINT_num(x->crldp); i++) {
1291 DIST_POINT *dp = sk_DIST_POINT_value(x->crldp, i);
1292 if (crldp_check_crlissuer(dp, crl, crl_score)) {
1293 if (!crl->idp || idp_check_dp(dp->distpoint, crl->idp->distpoint)) {
1294 *preasons &= dp->dp_reasons;
1299 if ((!crl->idp || !crl->idp->distpoint)
1300 && (crl_score & CRL_SCORE_ISSUER_NAME))
1306 * Retrieve CRL corresponding to current certificate. If deltas enabled try
1307 * to find a delta CRL too
1310 static int get_crl_delta(X509_STORE_CTX *ctx,
1311 X509_CRL **pcrl, X509_CRL **pdcrl, X509 *x)
1314 X509 *issuer = NULL;
1316 unsigned int reasons;
1317 X509_CRL *crl = NULL, *dcrl = NULL;
1318 STACK_OF(X509_CRL) *skcrl;
1319 X509_NAME *nm = X509_get_issuer_name(x);
1321 reasons = ctx->current_reasons;
1322 ok = get_crl_sk(ctx, &crl, &dcrl,
1323 &issuer, &crl_score, &reasons, ctx->crls);
1327 /* Lookup CRLs from store */
1329 skcrl = ctx->lookup_crls(ctx, nm);
1331 /* If no CRLs found and a near match from get_crl_sk use that */
1335 get_crl_sk(ctx, &crl, &dcrl, &issuer, &crl_score, &reasons, skcrl);
1337 sk_X509_CRL_pop_free(skcrl, X509_CRL_free);
1340 /* If we got any kind of CRL use it and return success */
1342 ctx->current_issuer = issuer;
1343 ctx->current_crl_score = crl_score;
1344 ctx->current_reasons = reasons;
1352 /* Check CRL validity */
1353 static int check_crl(X509_STORE_CTX *ctx, X509_CRL *crl)
1355 X509 *issuer = NULL;
1356 EVP_PKEY *ikey = NULL;
1357 int cnum = ctx->error_depth;
1358 int chnum = sk_X509_num(ctx->chain) - 1;
1360 /* if we have an alternative CRL issuer cert use that */
1361 if (ctx->current_issuer)
1362 issuer = ctx->current_issuer;
1364 * Else find CRL issuer: if not last certificate then issuer is next
1365 * certificate in chain.
1367 else if (cnum < chnum)
1368 issuer = sk_X509_value(ctx->chain, cnum + 1);
1370 issuer = sk_X509_value(ctx->chain, chnum);
1371 /* If not self signed, can't check signature */
1372 if (!ctx->check_issued(ctx, issuer, issuer) &&
1373 !verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL_ISSUER))
1381 * Skip most tests for deltas because they have already been done
1383 if (!crl->base_crl_number) {
1384 /* Check for cRLSign bit if keyUsage present */
1385 if ((issuer->ex_flags & EXFLAG_KUSAGE) &&
1386 !(issuer->ex_kusage & KU_CRL_SIGN) &&
1387 !verify_cb_crl(ctx, X509_V_ERR_KEYUSAGE_NO_CRL_SIGN))
1390 if (!(ctx->current_crl_score & CRL_SCORE_SCOPE) &&
1391 !verify_cb_crl(ctx, X509_V_ERR_DIFFERENT_CRL_SCOPE))
1394 if (!(ctx->current_crl_score & CRL_SCORE_SAME_PATH) &&
1395 check_crl_path(ctx, ctx->current_issuer) <= 0 &&
1396 !verify_cb_crl(ctx, X509_V_ERR_CRL_PATH_VALIDATION_ERROR))
1399 if ((crl->idp_flags & IDP_INVALID) &&
1400 !verify_cb_crl(ctx, X509_V_ERR_INVALID_EXTENSION))
1404 if (!(ctx->current_crl_score & CRL_SCORE_TIME) &&
1405 !check_crl_time(ctx, crl, 1))
1408 /* Attempt to get issuer certificate public key */
1409 ikey = X509_get0_pubkey(issuer);
1412 !verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY))
1416 int rv = X509_CRL_check_suiteb(crl, ikey, ctx->param->flags);
1418 if (rv != X509_V_OK && !verify_cb_crl(ctx, rv))
1420 /* Verify CRL signature */
1421 if (X509_CRL_verify(crl, ikey) <= 0 &&
1422 !verify_cb_crl(ctx, X509_V_ERR_CRL_SIGNATURE_FAILURE))
1428 /* Check certificate against CRL */
1429 static int cert_crl(X509_STORE_CTX *ctx, X509_CRL *crl, X509 *x)
1434 * The rules changed for this... previously if a CRL contained unhandled
1435 * critical extensions it could still be used to indicate a certificate
1436 * was revoked. This has since been changed since critical extensions can
1437 * change the meaning of CRL entries.
1439 if (!(ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL)
1440 && (crl->flags & EXFLAG_CRITICAL) &&
1441 !verify_cb_crl(ctx, X509_V_ERR_UNHANDLED_CRITICAL_CRL_EXTENSION))
1444 * Look for serial number of certificate in CRL. If found, make sure
1445 * reason is not removeFromCRL.
1447 if (X509_CRL_get0_by_cert(crl, &rev, x)) {
1448 if (rev->reason == CRL_REASON_REMOVE_FROM_CRL)
1450 if (!verify_cb_crl(ctx, X509_V_ERR_CERT_REVOKED))
1457 static int check_policy(X509_STORE_CTX *ctx)
1464 * With DANE, the trust anchor might be a bare public key, not a
1465 * certificate! In that case our chain does not have the trust anchor
1466 * certificate as a top-most element. This comports well with RFC5280
1467 * chain verification, since there too, the trust anchor is not part of the
1468 * chain to be verified. In particular, X509_policy_check() does not look
1469 * at the TA cert, but assumes that it is present as the top-most chain
1470 * element. We therefore temporarily push a NULL cert onto the chain if it
1471 * was verified via a bare public key, and pop it off right after the
1472 * X509_policy_check() call.
1474 if (ctx->bare_ta_signed && !sk_X509_push(ctx->chain, NULL)) {
1475 X509err(X509_F_CHECK_POLICY, ERR_R_MALLOC_FAILURE);
1476 ctx->error = X509_V_ERR_OUT_OF_MEM;
1479 ret = X509_policy_check(&ctx->tree, &ctx->explicit_policy, ctx->chain,
1480 ctx->param->policies, ctx->param->flags);
1481 if (ctx->bare_ta_signed)
1482 sk_X509_pop(ctx->chain);
1484 if (ret == X509_PCY_TREE_INTERNAL) {
1485 X509err(X509_F_CHECK_POLICY, ERR_R_MALLOC_FAILURE);
1486 ctx->error = X509_V_ERR_OUT_OF_MEM;
1489 /* Invalid or inconsistent extensions */
1490 if (ret == X509_PCY_TREE_INVALID) {
1493 /* Locate certificates with bad extensions and notify callback. */
1494 for (i = 1; i < sk_X509_num(ctx->chain); i++) {
1495 X509 *x = sk_X509_value(ctx->chain, i);
1497 if (!(x->ex_flags & EXFLAG_INVALID_POLICY))
1499 if (!verify_cb_cert(ctx, x, i,
1500 X509_V_ERR_INVALID_POLICY_EXTENSION))
1505 if (ret == X509_PCY_TREE_FAILURE) {
1506 ctx->current_cert = NULL;
1507 ctx->error = X509_V_ERR_NO_EXPLICIT_POLICY;
1508 return ctx->verify_cb(0, ctx);
1510 if (ret != X509_PCY_TREE_VALID) {
1511 X509err(X509_F_CHECK_POLICY, ERR_R_INTERNAL_ERROR);
1515 if (ctx->param->flags & X509_V_FLAG_NOTIFY_POLICY) {
1516 ctx->current_cert = NULL;
1518 * Verification errors need to be "sticky", a callback may have allowed
1519 * an SSL handshake to continue despite an error, and we must then
1520 * remain in an error state. Therefore, we MUST NOT clear earlier
1521 * verification errors by setting the error to X509_V_OK.
1523 if (!ctx->verify_cb(2, ctx))
1531 * Check certificate validity times.
1532 * If depth >= 0, invoke verification callbacks on error, otherwise just return
1533 * the validation status.
1535 * Return 1 on success, 0 otherwise.
1537 int x509_check_cert_time(X509_STORE_CTX *ctx, X509 *x, int depth)
1542 if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME)
1543 ptime = &ctx->param->check_time;
1544 else if (ctx->param->flags & X509_V_FLAG_NO_CHECK_TIME)
1549 i = X509_cmp_time(X509_get_notBefore(x), ptime);
1550 if (i >= 0 && depth < 0)
1552 if (i == 0 && !verify_cb_cert(ctx, x, depth,
1553 X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD))
1555 if (i > 0 && !verify_cb_cert(ctx, x, depth, X509_V_ERR_CERT_NOT_YET_VALID))
1558 i = X509_cmp_time(X509_get_notAfter(x), ptime);
1559 if (i <= 0 && depth < 0)
1561 if (i == 0 && !verify_cb_cert(ctx, x, depth,
1562 X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD))
1564 if (i < 0 && !verify_cb_cert(ctx, x, depth, X509_V_ERR_CERT_HAS_EXPIRED))
1569 static int internal_verify(X509_STORE_CTX *ctx)
1571 int n = sk_X509_num(ctx->chain) - 1;
1572 X509 *xi = sk_X509_value(ctx->chain, n);
1576 * With DANE-verified bare public key TA signatures, it remains only to
1577 * check the timestamps of the top certificate. We report the issuer as
1578 * NULL, since all we have is a bare key.
1580 if (ctx->bare_ta_signed) {
1586 if (ctx->check_issued(ctx, xi, xi))
1589 if (ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) {
1594 return verify_cb_cert(ctx, xi, 0,
1595 X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE);
1597 ctx->error_depth = n;
1598 xs = sk_X509_value(ctx->chain, n);
1602 * Do not clear ctx->error=0, it must be "sticky", only the user's callback
1603 * is allowed to reset errors (at its own peril).
1609 * Skip signature check for self signed certificates unless explicitly
1610 * asked for. It doesn't add any security and just wastes time. If
1611 * the issuer's public key is unusable, report the issuer certificate
1612 * and its depth (rather than the depth of the subject).
1614 if (xs != xi || (ctx->param->flags & X509_V_FLAG_CHECK_SS_SIGNATURE)) {
1615 if ((pkey = X509_get0_pubkey(xi)) == NULL) {
1616 if (!verify_cb_cert(ctx, xi, xi != xs ? n+1 : n,
1617 X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY))
1619 } else if (X509_verify(xs, pkey) <= 0) {
1620 if (!verify_cb_cert(ctx, xs, n,
1621 X509_V_ERR_CERT_SIGNATURE_FAILURE))
1627 /* Calls verify callback as needed */
1628 if (!x509_check_cert_time(ctx, xs, n))
1632 * Signal success at this depth. However, the previous error (if any)
1635 ctx->current_issuer = xi;
1636 ctx->current_cert = xs;
1637 ctx->error_depth = n;
1638 if (!ctx->verify_cb(1, ctx))
1643 xs = sk_X509_value(ctx->chain, n);
1649 int X509_cmp_current_time(const ASN1_TIME *ctm)
1651 return X509_cmp_time(ctm, NULL);
1654 int X509_cmp_time(const ASN1_TIME *ctm, time_t *cmp_time)
1659 char buff1[24], buff2[24], *p;
1660 int i, j, remaining;
1663 remaining = ctm->length;
1664 str = (char *)ctm->data;
1666 * Note that the following (historical) code allows much more slack in the
1667 * time format than RFC5280. In RFC5280, the representation is fixed:
1668 * UTCTime: YYMMDDHHMMSSZ
1669 * GeneralizedTime: YYYYMMDDHHMMSSZ
1671 if (ctm->type == V_ASN1_UTCTIME) {
1672 /* YYMMDDHHMM[SS]Z or YYMMDDHHMM[SS](+-)hhmm */
1673 int min_length = sizeof("YYMMDDHHMMZ") - 1;
1674 int max_length = sizeof("YYMMDDHHMMSS+hhmm") - 1;
1675 if (remaining < min_length || remaining > max_length)
1682 /* YYYYMMDDHHMM[SS[.fff]]Z or YYYYMMDDHHMM[SS[.f[f[f]]]](+-)hhmm */
1683 int min_length = sizeof("YYYYMMDDHHMMZ") - 1;
1684 int max_length = sizeof("YYYYMMDDHHMMSS.fff+hhmm") - 1;
1685 if (remaining < min_length || remaining > max_length)
1693 if ((*str == 'Z') || (*str == '-') || (*str == '+')) {
1704 * Skip any (up to three) fractional seconds...
1705 * TODO(emilia): in RFC5280, fractional seconds are forbidden.
1706 * Can we just kill them altogether?
1708 if (remaining && *str == '.') {
1711 for (i = 0; i < 3 && remaining; i++, str++, remaining--) {
1712 if (*str < '0' || *str > '9')
1721 /* We now need either a terminating 'Z' or an offset. */
1730 if ((*str != '+') && (*str != '-'))
1732 /* Historical behaviour: the (+-)hhmm offset is forbidden in RFC5280. */
1735 if (str[1] < '0' || str[1] > '9' || str[2] < '0' || str[2] > '9' ||
1736 str[3] < '0' || str[3] > '9' || str[4] < '0' || str[4] > '9')
1738 offset = ((str[1] - '0') * 10 + (str[2] - '0')) * 60;
1739 offset += (str[3] - '0') * 10 + (str[4] - '0');
1743 atm.type = ctm->type;
1745 atm.length = sizeof(buff2);
1746 atm.data = (unsigned char *)buff2;
1748 if (X509_time_adj(&atm, offset * 60, cmp_time) == NULL)
1751 if (ctm->type == V_ASN1_UTCTIME) {
1752 i = (buff1[0] - '0') * 10 + (buff1[1] - '0');
1754 i += 100; /* cf. RFC 2459 */
1755 j = (buff2[0] - '0') * 10 + (buff2[1] - '0');
1764 i = strcmp(buff1, buff2);
1765 if (i == 0) /* wait a second then return younger :-) */
1771 ASN1_TIME *X509_gmtime_adj(ASN1_TIME *s, long adj)
1773 return X509_time_adj(s, adj, NULL);
1776 ASN1_TIME *X509_time_adj(ASN1_TIME *s, long offset_sec, time_t *in_tm)
1778 return X509_time_adj_ex(s, 0, offset_sec, in_tm);
1781 ASN1_TIME *X509_time_adj_ex(ASN1_TIME *s,
1782 int offset_day, long offset_sec, time_t *in_tm)
1791 if (s && !(s->flags & ASN1_STRING_FLAG_MSTRING)) {
1792 if (s->type == V_ASN1_UTCTIME)
1793 return ASN1_UTCTIME_adj(s, t, offset_day, offset_sec);
1794 if (s->type == V_ASN1_GENERALIZEDTIME)
1795 return ASN1_GENERALIZEDTIME_adj(s, t, offset_day, offset_sec);
1797 return ASN1_TIME_adj(s, t, offset_day, offset_sec);
1800 int X509_get_pubkey_parameters(EVP_PKEY *pkey, STACK_OF(X509) *chain)
1802 EVP_PKEY *ktmp = NULL, *ktmp2;
1805 if ((pkey != NULL) && !EVP_PKEY_missing_parameters(pkey))
1808 for (i = 0; i < sk_X509_num(chain); i++) {
1809 ktmp = X509_get0_pubkey(sk_X509_value(chain, i));
1811 X509err(X509_F_X509_GET_PUBKEY_PARAMETERS,
1812 X509_R_UNABLE_TO_GET_CERTS_PUBLIC_KEY);
1815 if (!EVP_PKEY_missing_parameters(ktmp))
1819 X509err(X509_F_X509_GET_PUBKEY_PARAMETERS,
1820 X509_R_UNABLE_TO_FIND_PARAMETERS_IN_CHAIN);
1824 /* first, populate the other certs */
1825 for (j = i - 1; j >= 0; j--) {
1826 ktmp2 = X509_get0_pubkey(sk_X509_value(chain, j));
1827 EVP_PKEY_copy_parameters(ktmp2, ktmp);
1831 EVP_PKEY_copy_parameters(pkey, ktmp);
1835 /* Make a delta CRL as the diff between two full CRLs */
1837 X509_CRL *X509_CRL_diff(X509_CRL *base, X509_CRL *newer,
1838 EVP_PKEY *skey, const EVP_MD *md, unsigned int flags)
1840 X509_CRL *crl = NULL;
1842 STACK_OF(X509_REVOKED) *revs = NULL;
1843 /* CRLs can't be delta already */
1844 if (base->base_crl_number || newer->base_crl_number) {
1845 X509err(X509_F_X509_CRL_DIFF, X509_R_CRL_ALREADY_DELTA);
1848 /* Base and new CRL must have a CRL number */
1849 if (!base->crl_number || !newer->crl_number) {
1850 X509err(X509_F_X509_CRL_DIFF, X509_R_NO_CRL_NUMBER);
1853 /* Issuer names must match */
1854 if (X509_NAME_cmp(X509_CRL_get_issuer(base), X509_CRL_get_issuer(newer))) {
1855 X509err(X509_F_X509_CRL_DIFF, X509_R_ISSUER_MISMATCH);
1858 /* AKID and IDP must match */
1859 if (!crl_extension_match(base, newer, NID_authority_key_identifier)) {
1860 X509err(X509_F_X509_CRL_DIFF, X509_R_AKID_MISMATCH);
1863 if (!crl_extension_match(base, newer, NID_issuing_distribution_point)) {
1864 X509err(X509_F_X509_CRL_DIFF, X509_R_IDP_MISMATCH);
1867 /* Newer CRL number must exceed full CRL number */
1868 if (ASN1_INTEGER_cmp(newer->crl_number, base->crl_number) <= 0) {
1869 X509err(X509_F_X509_CRL_DIFF, X509_R_NEWER_CRL_NOT_NEWER);
1872 /* CRLs must verify */
1873 if (skey && (X509_CRL_verify(base, skey) <= 0 ||
1874 X509_CRL_verify(newer, skey) <= 0)) {
1875 X509err(X509_F_X509_CRL_DIFF, X509_R_CRL_VERIFY_FAILURE);
1878 /* Create new CRL */
1879 crl = X509_CRL_new();
1880 if (crl == NULL || !X509_CRL_set_version(crl, 1))
1882 /* Set issuer name */
1883 if (!X509_CRL_set_issuer_name(crl, X509_CRL_get_issuer(newer)))
1886 if (!X509_CRL_set_lastUpdate(crl, X509_CRL_get_lastUpdate(newer)))
1888 if (!X509_CRL_set_nextUpdate(crl, X509_CRL_get_nextUpdate(newer)))
1891 /* Set base CRL number: must be critical */
1893 if (!X509_CRL_add1_ext_i2d(crl, NID_delta_crl, base->crl_number, 1, 0))
1897 * Copy extensions across from newest CRL to delta: this will set CRL
1898 * number to correct value too.
1901 for (i = 0; i < X509_CRL_get_ext_count(newer); i++) {
1902 X509_EXTENSION *ext;
1903 ext = X509_CRL_get_ext(newer, i);
1904 if (!X509_CRL_add_ext(crl, ext, -1))
1908 /* Go through revoked entries, copying as needed */
1910 revs = X509_CRL_get_REVOKED(newer);
1912 for (i = 0; i < sk_X509_REVOKED_num(revs); i++) {
1913 X509_REVOKED *rvn, *rvtmp;
1914 rvn = sk_X509_REVOKED_value(revs, i);
1916 * Add only if not also in base. TODO: need something cleverer here
1917 * for some more complex CRLs covering multiple CAs.
1919 if (!X509_CRL_get0_by_serial(base, &rvtmp, &rvn->serialNumber)) {
1920 rvtmp = X509_REVOKED_dup(rvn);
1923 if (!X509_CRL_add0_revoked(crl, rvtmp)) {
1924 X509_REVOKED_free(rvtmp);
1929 /* TODO: optionally prune deleted entries */
1931 if (skey && md && !X509_CRL_sign(crl, skey, md))
1937 X509err(X509_F_X509_CRL_DIFF, ERR_R_MALLOC_FAILURE);
1942 int X509_STORE_CTX_set_ex_data(X509_STORE_CTX *ctx, int idx, void *data)
1944 return CRYPTO_set_ex_data(&ctx->ex_data, idx, data);
1947 void *X509_STORE_CTX_get_ex_data(X509_STORE_CTX *ctx, int idx)
1949 return CRYPTO_get_ex_data(&ctx->ex_data, idx);
1952 int X509_STORE_CTX_get_error(X509_STORE_CTX *ctx)
1957 void X509_STORE_CTX_set_error(X509_STORE_CTX *ctx, int err)
1962 int X509_STORE_CTX_get_error_depth(X509_STORE_CTX *ctx)
1964 return ctx->error_depth;
1967 void X509_STORE_CTX_set_error_depth(X509_STORE_CTX *ctx, int depth)
1969 ctx->error_depth = depth;
1972 X509 *X509_STORE_CTX_get_current_cert(X509_STORE_CTX *ctx)
1974 return ctx->current_cert;
1977 void X509_STORE_CTX_set_current_cert(X509_STORE_CTX *ctx, X509 *x)
1979 ctx->current_cert = x;
1982 STACK_OF(X509) *X509_STORE_CTX_get0_chain(X509_STORE_CTX *ctx)
1987 STACK_OF(X509) *X509_STORE_CTX_get1_chain(X509_STORE_CTX *ctx)
1991 return X509_chain_up_ref(ctx->chain);
1994 X509 *X509_STORE_CTX_get0_current_issuer(X509_STORE_CTX *ctx)
1996 return ctx->current_issuer;
1999 X509_CRL *X509_STORE_CTX_get0_current_crl(X509_STORE_CTX *ctx)
2001 return ctx->current_crl;
2004 X509_STORE_CTX *X509_STORE_CTX_get0_parent_ctx(X509_STORE_CTX *ctx)
2009 void X509_STORE_CTX_set_cert(X509_STORE_CTX *ctx, X509 *x)
2014 void X509_STORE_CTX_set0_crls(X509_STORE_CTX *ctx, STACK_OF(X509_CRL) *sk)
2019 int X509_STORE_CTX_set_purpose(X509_STORE_CTX *ctx, int purpose)
2022 * XXX: Why isn't this function always used to set the associated trust?
2023 * Should there even be a VPM->trust field at all? Or should the trust
2024 * always be inferred from the purpose by X509_STORE_CTX_init().
2026 return X509_STORE_CTX_purpose_inherit(ctx, 0, purpose, 0);
2029 int X509_STORE_CTX_set_trust(X509_STORE_CTX *ctx, int trust)
2032 * XXX: See above, this function would only be needed when the default
2033 * trust for the purpose needs an override in a corner case.
2035 return X509_STORE_CTX_purpose_inherit(ctx, 0, 0, trust);
2039 * This function is used to set the X509_STORE_CTX purpose and trust values.
2040 * This is intended to be used when another structure has its own trust and
2041 * purpose values which (if set) will be inherited by the ctx. If they aren't
2042 * set then we will usually have a default purpose in mind which should then
2043 * be used to set the trust value. An example of this is SSL use: an SSL
2044 * structure will have its own purpose and trust settings which the
2045 * application can set: if they aren't set then we use the default of SSL
2049 int X509_STORE_CTX_purpose_inherit(X509_STORE_CTX *ctx, int def_purpose,
2050 int purpose, int trust)
2053 /* If purpose not set use default */
2055 purpose = def_purpose;
2056 /* If we have a purpose then check it is valid */
2059 idx = X509_PURPOSE_get_by_id(purpose);
2061 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2062 X509_R_UNKNOWN_PURPOSE_ID);
2065 ptmp = X509_PURPOSE_get0(idx);
2066 if (ptmp->trust == X509_TRUST_DEFAULT) {
2067 idx = X509_PURPOSE_get_by_id(def_purpose);
2069 * XXX: In the two callers above def_purpose is always 0, which is
2070 * not a known value, so idx will always be -1. How is the
2071 * X509_TRUST_DEFAULT case actually supposed to be handled?
2074 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2075 X509_R_UNKNOWN_PURPOSE_ID);
2078 ptmp = X509_PURPOSE_get0(idx);
2080 /* If trust not set then get from purpose default */
2082 trust = ptmp->trust;
2085 idx = X509_TRUST_get_by_id(trust);
2087 X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
2088 X509_R_UNKNOWN_TRUST_ID);
2093 if (purpose && !ctx->param->purpose)
2094 ctx->param->purpose = purpose;
2095 if (trust && !ctx->param->trust)
2096 ctx->param->trust = trust;
2100 X509_STORE_CTX *X509_STORE_CTX_new(void)
2102 X509_STORE_CTX *ctx = OPENSSL_zalloc(sizeof(*ctx));
2105 X509err(X509_F_X509_STORE_CTX_NEW, ERR_R_MALLOC_FAILURE);
2111 void X509_STORE_CTX_free(X509_STORE_CTX *ctx)
2116 X509_STORE_CTX_cleanup(ctx);
2120 int X509_STORE_CTX_init(X509_STORE_CTX *ctx, X509_STORE *store, X509 *x509,
2121 STACK_OF(X509) *chain)
2126 ctx->current_method = 0;
2128 ctx->untrusted = chain;
2130 ctx->num_untrusted = 0;
2131 ctx->other_ctx = NULL;
2135 ctx->explicit_policy = 0;
2136 ctx->error_depth = 0;
2137 ctx->current_cert = NULL;
2138 ctx->current_issuer = NULL;
2139 ctx->current_crl = NULL;
2140 ctx->current_crl_score = 0;
2141 ctx->current_reasons = 0;
2145 ctx->bare_ta_signed = 0;
2146 /* Zero ex_data to make sure we're cleanup-safe */
2147 memset(&ctx->ex_data, 0, sizeof(ctx->ex_data));
2149 /* store->cleanup is always 0 in OpenSSL, if set must be idempotent */
2151 ctx->cleanup = store->cleanup;
2155 if (store && store->check_issued)
2156 ctx->check_issued = store->check_issued;
2158 ctx->check_issued = check_issued;
2160 if (store && store->get_issuer)
2161 ctx->get_issuer = store->get_issuer;
2163 ctx->get_issuer = X509_STORE_CTX_get1_issuer;
2165 if (store && store->verify_cb)
2166 ctx->verify_cb = store->verify_cb;
2168 ctx->verify_cb = null_callback;
2170 if (store && store->verify)
2171 ctx->verify = store->verify;
2173 ctx->verify = internal_verify;
2175 if (store && store->check_revocation)
2176 ctx->check_revocation = store->check_revocation;
2178 ctx->check_revocation = check_revocation;
2180 if (store && store->get_crl)
2181 ctx->get_crl = store->get_crl;
2183 ctx->get_crl = NULL;
2185 if (store && store->check_crl)
2186 ctx->check_crl = store->check_crl;
2188 ctx->check_crl = check_crl;
2190 if (store && store->cert_crl)
2191 ctx->cert_crl = store->cert_crl;
2193 ctx->cert_crl = cert_crl;
2195 if (store && store->lookup_certs)
2196 ctx->lookup_certs = store->lookup_certs;
2198 ctx->lookup_certs = X509_STORE_CTX_get1_certs;
2200 if (store && store->lookup_crls)
2201 ctx->lookup_crls = store->lookup_crls;
2203 ctx->lookup_crls = X509_STORE_CTX_get1_crls;
2205 ctx->check_policy = check_policy;
2207 ctx->param = X509_VERIFY_PARAM_new();
2208 if (ctx->param == NULL) {
2209 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2214 * Inherit callbacks and flags from X509_STORE if not set use defaults.
2217 ret = X509_VERIFY_PARAM_inherit(ctx->param, store->param);
2219 ctx->param->inh_flags |= X509_VP_FLAG_DEFAULT | X509_VP_FLAG_ONCE;
2222 ret = X509_VERIFY_PARAM_inherit(ctx->param,
2223 X509_VERIFY_PARAM_lookup("default"));
2226 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2231 * XXX: For now, continue to inherit trust from VPM, but infer from the
2232 * purpose if this still yields the default value.
2234 if (ctx->param->trust == X509_TRUST_DEFAULT) {
2235 int idx = X509_PURPOSE_get_by_id(ctx->param->purpose);
2236 X509_PURPOSE *xp = X509_PURPOSE_get0(idx);
2239 ctx->param->trust = X509_PURPOSE_get_trust(xp);
2242 if (CRYPTO_new_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx,
2245 X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE);
2249 * On error clean up allocated storage, if the store context was not
2250 * allocated with X509_STORE_CTX_new() this is our last chance to do so.
2252 X509_STORE_CTX_cleanup(ctx);
2257 * Set alternative lookup method: just a STACK of trusted certificates. This
2258 * avoids X509_STORE nastiness where it isn't needed.
2260 void X509_STORE_CTX_set0_trusted_stack(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2262 ctx->other_ctx = sk;
2263 ctx->get_issuer = get_issuer_sk;
2264 ctx->lookup_certs = lookup_certs_sk;
2267 void X509_STORE_CTX_cleanup(X509_STORE_CTX *ctx)
2270 * We need to be idempotent because, unfortunately, free() also calls
2271 * cleanup(), so the natural call sequence new(), init(), cleanup(), free()
2272 * calls cleanup() for the same object twice! Thus we must zero the
2273 * pointers below after they're freed!
2275 /* Seems to always be 0 in OpenSSL, do this at most once. */
2276 if (ctx->cleanup != NULL) {
2278 ctx->cleanup = NULL;
2280 if (ctx->param != NULL) {
2281 if (ctx->parent == NULL)
2282 X509_VERIFY_PARAM_free(ctx->param);
2285 X509_policy_tree_free(ctx->tree);
2287 sk_X509_pop_free(ctx->chain, X509_free);
2289 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx, &(ctx->ex_data));
2290 memset(&ctx->ex_data, 0, sizeof(ctx->ex_data));
2293 void X509_STORE_CTX_set_depth(X509_STORE_CTX *ctx, int depth)
2295 X509_VERIFY_PARAM_set_depth(ctx->param, depth);
2298 void X509_STORE_CTX_set_flags(X509_STORE_CTX *ctx, unsigned long flags)
2300 X509_VERIFY_PARAM_set_flags(ctx->param, flags);
2303 void X509_STORE_CTX_set_time(X509_STORE_CTX *ctx, unsigned long flags,
2306 X509_VERIFY_PARAM_set_time(ctx->param, t);
2309 void X509_STORE_CTX_set_verify_cb(X509_STORE_CTX *ctx,
2310 X509_STORE_CTX_verify_cb verify_cb)
2312 ctx->verify_cb = verify_cb;
2315 X509_STORE_CTX_verify_cb X509_STORE_CTX_get_verify_cb(X509_STORE_CTX *ctx)
2317 return ctx->verify_cb;
2320 X509 *X509_STORE_CTX_get0_cert(X509_STORE_CTX *ctx)
2325 STACK_OF(X509) *X509_STORE_CTX_get0_untrusted(X509_STORE_CTX *ctx)
2327 return ctx->untrusted;
2330 void X509_STORE_CTX_set0_untrusted(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2332 ctx->untrusted = sk;
2335 void X509_STORE_CTX_set0_verified_chain(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2337 sk_X509_pop_free(ctx->chain, X509_free);
2341 void X509_STORE_CTX_set_verify(X509_STORE_CTX *ctx,
2342 X509_STORE_CTX_verify verify)
2344 ctx->verify = verify;
2347 X509_STORE_CTX_verify X509_STORE_CTX_get_verify(X509_STORE_CTX *ctx)
2352 X509_POLICY_TREE *X509_STORE_CTX_get0_policy_tree(X509_STORE_CTX *ctx)
2357 int X509_STORE_CTX_get_explicit_policy(X509_STORE_CTX *ctx)
2359 return ctx->explicit_policy;
2362 int X509_STORE_CTX_get_num_untrusted(X509_STORE_CTX *ctx)
2364 return ctx->num_untrusted;
2367 int X509_STORE_CTX_set_default(X509_STORE_CTX *ctx, const char *name)
2369 const X509_VERIFY_PARAM *param;
2370 param = X509_VERIFY_PARAM_lookup(name);
2373 return X509_VERIFY_PARAM_inherit(ctx->param, param);
2376 X509_VERIFY_PARAM *X509_STORE_CTX_get0_param(X509_STORE_CTX *ctx)
2381 void X509_STORE_CTX_set0_param(X509_STORE_CTX *ctx, X509_VERIFY_PARAM *param)
2383 X509_VERIFY_PARAM_free(ctx->param);
2387 void X509_STORE_CTX_set0_dane(X509_STORE_CTX *ctx, SSL_DANE *dane)
2392 static unsigned char *dane_i2d(
2395 unsigned int *i2dlen)
2397 unsigned char *buf = NULL;
2401 * Extract ASN.1 DER form of certificate or public key.
2404 case DANETLS_SELECTOR_CERT:
2405 len = i2d_X509(cert, &buf);
2407 case DANETLS_SELECTOR_SPKI:
2408 len = i2d_X509_PUBKEY(X509_get_X509_PUBKEY(cert), &buf);
2411 X509err(X509_F_DANE_I2D, X509_R_BAD_SELECTOR);
2415 if (len < 0 || buf == NULL) {
2416 X509err(X509_F_DANE_I2D, ERR_R_MALLOC_FAILURE);
2420 *i2dlen = (unsigned int)len;
2424 #define DANETLS_NONE 256 /* impossible uint8_t */
2426 static int dane_match(X509_STORE_CTX *ctx, X509 *cert, int depth)
2428 SSL_DANE *dane = ctx->dane;
2429 unsigned usage = DANETLS_NONE;
2430 unsigned selector = DANETLS_NONE;
2431 unsigned ordinal = DANETLS_NONE;
2432 unsigned mtype = DANETLS_NONE;
2433 unsigned char *i2dbuf = NULL;
2434 unsigned int i2dlen = 0;
2435 unsigned char mdbuf[EVP_MAX_MD_SIZE];
2436 unsigned char *cmpbuf = NULL;
2437 unsigned int cmplen = 0;
2441 danetls_record *t = NULL;
2444 mask = (depth == 0) ? DANETLS_EE_MASK : DANETLS_TA_MASK;
2447 * The trust store is not applicable with DANE-TA(2)
2449 if (depth >= ctx->num_untrusted)
2450 mask &= DANETLS_PKIX_MASK;
2453 * If we've previously matched a PKIX-?? record, no need to test any
2454 * further PKIX-?? records, it remains to just build the PKIX chain.
2455 * Had the match been a DANE-?? record, we'd be done already.
2457 if (dane->mdpth >= 0)
2458 mask &= ~DANETLS_PKIX_MASK;
2461 * https://tools.ietf.org/html/rfc7671#section-5.1
2462 * https://tools.ietf.org/html/rfc7671#section-5.2
2463 * https://tools.ietf.org/html/rfc7671#section-5.3
2464 * https://tools.ietf.org/html/rfc7671#section-5.4
2466 * We handle DANE-EE(3) records first as they require no chain building
2467 * and no expiration or hostname checks. We also process digests with
2468 * higher ordinals first and ignore lower priorities except Full(0) which
2469 * is always processed (last). If none match, we then process PKIX-EE(1).
2471 * NOTE: This relies on DANE usages sorting before the corresponding PKIX
2472 * usages in SSL_dane_tlsa_add(), and also on descending sorting of digest
2473 * priorities. See twin comment in ssl/ssl_lib.c.
2475 * We expect that most TLSA RRsets will have just a single usage, so we
2476 * don't go out of our way to cache multiple selector-specific i2d buffers
2477 * across usages, but if the selector happens to remain the same as switch
2478 * usages, that's OK. Thus, a set of "3 1 1", "3 0 1", "1 1 1", "1 0 1",
2479 * records would result in us generating each of the certificate and public
2480 * key DER forms twice, but more typically we'd just see multiple "3 1 1"
2481 * or multiple "3 0 1" records.
2483 * As soon as we find a match at any given depth, we stop, because either
2484 * we've matched a DANE-?? record and the peer is authenticated, or, after
2485 * exhausting all DANE-?? records, we've matched a PKIX-?? record, which is
2486 * sufficient for DANE, and what remains to do is ordinary PKIX validation.
2488 recnum = (dane->umask & mask) ? sk_danetls_record_num(dane->trecs) : 0;
2489 for (i = 0; matched == 0 && i < recnum; ++i) {
2490 t = sk_danetls_record_value(dane->trecs, i);
2491 if ((DANETLS_USAGE_BIT(t->usage) & mask) == 0)
2493 if (t->usage != usage) {
2496 /* Reset digest agility for each usage/selector pair */
2497 mtype = DANETLS_NONE;
2498 ordinal = dane->dctx->mdord[t->mtype];
2500 if (t->selector != selector) {
2501 selector = t->selector;
2503 /* Update per-selector state */
2504 OPENSSL_free(i2dbuf);
2505 i2dbuf = dane_i2d(cert, selector, &i2dlen);
2509 /* Reset digest agility for each usage/selector pair */
2510 mtype = DANETLS_NONE;
2511 ordinal = dane->dctx->mdord[t->mtype];
2512 } else if (t->mtype != DANETLS_MATCHING_FULL) {
2516 * <https://tools.ietf.org/html/rfc7671#section-9>
2518 * For a fixed selector, after processing all records with the
2519 * highest mtype ordinal, ignore all mtypes with lower ordinals
2520 * other than "Full".
2522 if (dane->dctx->mdord[t->mtype] < ordinal)
2527 * Each time we hit a (new selector or) mtype, re-compute the relevant
2528 * digest, more complex caching is not worth the code space.
2530 if (t->mtype != mtype) {
2531 const EVP_MD *md = dane->dctx->mdevp[mtype = t->mtype];
2537 if (!EVP_Digest(i2dbuf, i2dlen, cmpbuf, &cmplen, md, 0)) {
2545 * Squirrel away the certificate and depth if we have a match. Any
2546 * DANE match is dispositive, but with PKIX we still need to build a
2549 if (cmplen == t->dlen &&
2550 memcmp(cmpbuf, t->data, cmplen) == 0) {
2551 if (DANETLS_USAGE_BIT(usage) & DANETLS_DANE_MASK)
2553 if (matched || dane->mdpth < 0) {
2554 dane->mdpth = depth;
2556 OPENSSL_free(dane->mcert);
2564 /* Clear the one-element DER cache */
2565 OPENSSL_free(i2dbuf);
2569 static int check_dane_issuer(X509_STORE_CTX *ctx, int depth)
2571 SSL_DANE *dane = ctx->dane;
2575 if (!DANETLS_HAS_TA(dane) || depth == 0)
2576 return X509_TRUST_UNTRUSTED;
2579 * Record any DANE trust-anchor matches, for the first depth to test, if
2580 * there's one at that depth. (This'll be false for length 1 chains looking
2581 * for an exact match for the leaf certificate).
2583 cert = sk_X509_value(ctx->chain, depth);
2584 if (cert != NULL && (matched = dane_match(ctx, cert, depth)) < 0)
2585 return X509_TRUST_REJECTED;
2587 ctx->num_untrusted = depth - 1;
2588 return X509_TRUST_TRUSTED;
2591 return X509_TRUST_UNTRUSTED;
2594 static int check_dane_pkeys(X509_STORE_CTX *ctx)
2596 SSL_DANE *dane = ctx->dane;
2598 int num = ctx->num_untrusted;
2599 X509 *cert = sk_X509_value(ctx->chain, num - 1);
2600 int recnum = sk_danetls_record_num(dane->trecs);
2603 for (i = 0; i < recnum; ++i) {
2604 t = sk_danetls_record_value(dane->trecs, i);
2605 if (t->usage != DANETLS_USAGE_DANE_TA ||
2606 t->selector != DANETLS_SELECTOR_SPKI ||
2607 t->mtype != DANETLS_MATCHING_FULL ||
2608 X509_verify(cert, t->spki) <= 0)
2611 /* Clear any PKIX-?? matches that failed to extend to a full chain */
2612 X509_free(dane->mcert);
2615 /* Record match via a bare TA public key */
2616 ctx->bare_ta_signed = 1;
2617 dane->mdpth = num - 1;
2620 /* Prune any excess chain certificates */
2621 num = sk_X509_num(ctx->chain);
2622 for (; num > ctx->num_untrusted; --num)
2623 X509_free(sk_X509_pop(ctx->chain));
2625 return X509_TRUST_TRUSTED;
2628 return X509_TRUST_UNTRUSTED;
2631 static void dane_reset(SSL_DANE *dane)
2634 * Reset state to verify another chain, or clear after failure.
2636 X509_free(dane->mcert);
2643 static int check_leaf_suiteb(X509_STORE_CTX *ctx, X509 *cert)
2645 int err = X509_chain_check_suiteb(NULL, cert, NULL, ctx->param->flags);
2647 if (err == X509_V_OK)
2649 return verify_cb_cert(ctx, cert, 0, err);
2652 static int dane_verify(X509_STORE_CTX *ctx)
2654 X509 *cert = ctx->cert;
2655 SSL_DANE *dane = ctx->dane;
2662 * When testing the leaf certificate, if we match a DANE-EE(3) record,
2663 * dane_match() returns 1 and we're done. If however we match a PKIX-EE(1)
2664 * record, the match depth and matching TLSA record are recorded, but the
2665 * return value is 0, because we still need to find a PKIX trust-anchor.
2666 * Therefore, when DANE authentication is enabled (required), we're done
2668 * + matched < 0, internal error.
2669 * + matched == 1, we matched a DANE-EE(3) record
2670 * + matched == 0, mdepth < 0 (no PKIX-EE match) and there are no
2671 * DANE-TA(2) or PKIX-TA(0) to test.
2673 matched = dane_match(ctx, ctx->cert, 0);
2674 done = matched != 0 || (!DANETLS_HAS_TA(dane) && dane->mdpth < 0);
2677 X509_get_pubkey_parameters(NULL, ctx->chain);
2680 /* Callback invoked as needed */
2681 if (!check_leaf_suiteb(ctx, cert))
2683 /* Bypass internal_verify(), issue depth 0 success callback */
2684 ctx->error_depth = 0;
2685 ctx->current_cert = cert;
2686 return ctx->verify_cb(1, ctx);
2690 ctx->error_depth = 0;
2691 ctx->current_cert = cert;
2692 ctx->error = X509_V_ERR_OUT_OF_MEM;
2697 /* Fail early, TA-based success is not possible */
2698 if (!check_leaf_suiteb(ctx, cert))
2700 return verify_cb_cert(ctx, cert, 0, X509_V_ERR_DANE_NO_MATCH);
2704 * Chain verification for usages 0/1/2. TLSA record matching of depth > 0
2705 * certificates happens in-line with building the rest of the chain.
2707 return verify_chain(ctx);
2710 /* Get issuer, without duplicate suppression */
2711 static int get_issuer(X509 **issuer, X509_STORE_CTX *ctx, X509 *cert)
2713 STACK_OF(X509) *saved_chain = ctx->chain;
2717 ok = ctx->get_issuer(issuer, ctx, cert);
2718 ctx->chain = saved_chain;
2723 static int build_chain(X509_STORE_CTX *ctx)
2725 SSL_DANE *dane = ctx->dane;
2726 int num = sk_X509_num(ctx->chain);
2727 X509 *cert = sk_X509_value(ctx->chain, num - 1);
2728 int ss = cert_self_signed(cert);
2729 STACK_OF(X509) *sktmp = NULL;
2730 unsigned int search;
2731 int may_trusted = 0;
2732 int may_alternate = 0;
2733 int trust = X509_TRUST_UNTRUSTED;
2734 int alt_untrusted = 0;
2739 /* Our chain starts with a single untrusted element. */
2740 OPENSSL_assert(num == 1 && ctx->num_untrusted == num);
2742 #define S_DOUNTRUSTED (1 << 0) /* Search untrusted chain */
2743 #define S_DOTRUSTED (1 << 1) /* Search trusted store */
2744 #define S_DOALTERNATE (1 << 2) /* Retry with pruned alternate chain */
2746 * Set up search policy, untrusted if possible, trusted-first if enabled.
2747 * If we're doing DANE and not doing PKIX-TA/PKIX-EE, we never look in the
2748 * trust_store, otherwise we might look there first. If not trusted-first,
2749 * and alternate chains are not disabled, try building an alternate chain
2750 * if no luck with untrusted first.
2752 search = (ctx->untrusted != NULL) ? S_DOUNTRUSTED : 0;
2753 if (DANETLS_HAS_PKIX(dane) || !DANETLS_HAS_DANE(dane)) {
2754 if (search == 0 || ctx->param->flags & X509_V_FLAG_TRUSTED_FIRST)
2755 search |= S_DOTRUSTED;
2756 else if (!(ctx->param->flags & X509_V_FLAG_NO_ALT_CHAINS))
2762 * Shallow-copy the stack of untrusted certificates (with TLS, this is
2763 * typically the content of the peer's certificate message) so can make
2764 * multiple passes over it, while free to remove elements as we go.
2766 if (ctx->untrusted && (sktmp = sk_X509_dup(ctx->untrusted)) == NULL) {
2767 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2768 ctx->error = X509_V_ERR_OUT_OF_MEM;
2773 * If we got any "DANE-TA(2) Cert(0) Full(0)" trust-anchors from DNS, add
2774 * them to our working copy of the untrusted certificate stack. Since the
2775 * caller of X509_STORE_CTX_init() may have provided only a leaf cert with
2776 * no corresponding stack of untrusted certificates, we may need to create
2777 * an empty stack first. [ At present only the ssl library provides DANE
2778 * support, and ssl_verify_cert_chain() always provides a non-null stack
2779 * containing at least the leaf certificate, but we must be prepared for
2782 if (DANETLS_ENABLED(dane) && dane->certs != NULL) {
2783 if (sktmp == NULL && (sktmp = sk_X509_new_null()) == NULL) {
2784 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2785 ctx->error = X509_V_ERR_OUT_OF_MEM;
2788 for (i = 0; i < sk_X509_num(dane->certs); ++i) {
2789 if (!sk_X509_push(sktmp, sk_X509_value(dane->certs, i))) {
2790 sk_X509_free(sktmp);
2791 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2792 ctx->error = X509_V_ERR_OUT_OF_MEM;
2799 * Still absurdly large, but arithmetically safe, a lower hard upper bound
2800 * might be reasonable.
2802 if (ctx->param->depth > INT_MAX/2)
2803 ctx->param->depth = INT_MAX/2;
2806 * Try to Extend the chain until we reach an ultimately trusted issuer.
2807 * Build chains up to one longer the limit, later fail if we hit the limit,
2808 * with an X509_V_ERR_CERT_CHAIN_TOO_LONG error code.
2810 depth = ctx->param->depth + 1;
2812 while (search != 0) {
2817 * Look in the trust store if enabled for first lookup, or we've run
2818 * out of untrusted issuers and search here is not disabled. When we
2819 * reach the depth limit, we stop extending the chain, if by that point
2820 * we've not found a trust-anchor, any trusted chain would be too long.
2822 * The error reported to the application verify callback is at the
2823 * maximal valid depth with the current certificate equal to the last
2824 * not ultimately-trusted issuer. For example, with verify_depth = 0,
2825 * the callback will report errors at depth=1 when the immediate issuer
2826 * of the leaf certificate is not a trust anchor. No attempt will be
2827 * made to locate an issuer for that certificate, since such a chain
2828 * would be a-priori too long.
2830 if ((search & S_DOTRUSTED) != 0) {
2831 i = num = sk_X509_num(ctx->chain);
2832 if ((search & S_DOALTERNATE) != 0) {
2834 * As high up the chain as we can, look for an alternative
2835 * trusted issuer of an untrusted certificate that currently
2836 * has an untrusted issuer. We use the alt_untrusted variable
2837 * to track how far up the chain we find the first match. It
2838 * is only if and when we find a match, that we prune the chain
2839 * and reset ctx->num_untrusted to the reduced count of
2840 * untrusted certificates. While we're searching for such a
2841 * match (which may never be found), it is neither safe nor
2842 * wise to preemptively modify either the chain or
2843 * ctx->num_untrusted.
2845 * Note, like ctx->num_untrusted, alt_untrusted is a count of
2846 * untrusted certificates, not a "depth".
2850 x = sk_X509_value(ctx->chain, i-1);
2852 ok = (depth < num) ? 0 : get_issuer(&xtmp, ctx, x);
2855 trust = X509_TRUST_REJECTED;
2856 ctx->error = X509_V_ERR_STORE_LOOKUP;
2863 * Alternative trusted issuer for a mid-chain untrusted cert?
2864 * Pop the untrusted cert's successors and retry. We might now
2865 * be able to complete a valid chain via the trust store. Note
2866 * that despite the current trust-store match we might still
2867 * fail complete the chain to a suitable trust-anchor, in which
2868 * case we may prune some more untrusted certificates and try
2869 * again. Thus the S_DOALTERNATE bit may yet be turned on
2870 * again with an even shorter untrusted chain!
2872 * If in the process we threw away our matching PKIX-TA trust
2873 * anchor, reset DANE trust. We might find a suitable trusted
2874 * certificate among the ones from the trust store.
2876 if ((search & S_DOALTERNATE) != 0) {
2877 OPENSSL_assert(num > i && i > 0 && ss == 0);
2878 search &= ~S_DOALTERNATE;
2879 for (; num > i; --num)
2880 X509_free(sk_X509_pop(ctx->chain));
2881 ctx->num_untrusted = num;
2883 if (DANETLS_ENABLED(dane) &&
2884 dane->mdpth >= ctx->num_untrusted) {
2886 X509_free(dane->mcert);
2889 if (DANETLS_ENABLED(dane) &&
2890 dane->pdpth >= ctx->num_untrusted)
2895 * Self-signed untrusted certificates get replaced by their
2896 * trusted matching issuer. Otherwise, grow the chain.
2899 if (!sk_X509_push(ctx->chain, x = xtmp)) {
2901 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2902 trust = X509_TRUST_REJECTED;
2903 ctx->error = X509_V_ERR_OUT_OF_MEM;
2907 ss = cert_self_signed(x);
2908 } else if (num == ctx->num_untrusted) {
2910 * We have a self-signed certificate that has the same
2911 * subject name (and perhaps keyid and/or serial number) as
2912 * a trust-anchor. We must have an exact match to avoid
2913 * possible impersonation via key substitution etc.
2915 if (X509_cmp(x, xtmp) != 0) {
2916 /* Self-signed untrusted mimic. */
2921 ctx->num_untrusted = --num;
2922 (void) sk_X509_set(ctx->chain, num, x = xtmp);
2927 * We've added a new trusted certificate to the chain, recheck
2928 * trust. If not done, and not self-signed look deeper.
2929 * Whether or not we're doing "trusted first", we no longer
2930 * look for untrusted certificates from the peer's chain.
2932 * At this point ctx->num_trusted and num must reflect the
2933 * correct number of untrusted certificates, since the DANE
2934 * logic in check_trust() depends on distinguishing CAs from
2935 * "the wire" from CAs from the trust store. In particular, the
2936 * certificate at depth "num" should be the new trusted
2937 * certificate with ctx->num_untrusted <= num.
2940 OPENSSL_assert(ctx->num_untrusted <= num);
2941 search &= ~S_DOUNTRUSTED;
2942 switch (trust = check_trust(ctx, num)) {
2943 case X509_TRUST_TRUSTED:
2944 case X509_TRUST_REJECTED:
2954 * No dispositive decision, and either self-signed or no match, if
2955 * we were doing untrusted-first, and alt-chains are not disabled,
2956 * do that, by repeatedly losing one untrusted element at a time,
2957 * and trying to extend the shorted chain.
2959 if ((search & S_DOUNTRUSTED) == 0) {
2960 /* Continue search for a trusted issuer of a shorter chain? */
2961 if ((search & S_DOALTERNATE) != 0 && --alt_untrusted > 0)
2963 /* Still no luck and no fallbacks left? */
2964 if (!may_alternate || (search & S_DOALTERNATE) != 0 ||
2965 ctx->num_untrusted < 2)
2967 /* Search for a trusted issuer of a shorter chain */
2968 search |= S_DOALTERNATE;
2969 alt_untrusted = ctx->num_untrusted - 1;
2975 * Extend chain with peer-provided certificates
2977 if ((search & S_DOUNTRUSTED) != 0) {
2978 num = sk_X509_num(ctx->chain);
2979 OPENSSL_assert(num == ctx->num_untrusted);
2980 x = sk_X509_value(ctx->chain, num-1);
2983 * Once we run out of untrusted issuers, we stop looking for more
2984 * and start looking only in the trust store if enabled.
2986 xtmp = (ss || depth < num) ? NULL : find_issuer(ctx, sktmp, x);
2988 search &= ~S_DOUNTRUSTED;
2990 search |= S_DOTRUSTED;
2994 /* Drop this issuer from future consideration */
2995 (void) sk_X509_delete_ptr(sktmp, xtmp);
2997 if (!sk_X509_push(ctx->chain, xtmp)) {
2998 X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE);
2999 trust = X509_TRUST_REJECTED;
3000 ctx->error = X509_V_ERR_OUT_OF_MEM;
3005 X509_up_ref(x = xtmp);
3006 ++ctx->num_untrusted;
3007 ss = cert_self_signed(xtmp);
3010 * Check for DANE-TA trust of the topmost untrusted certificate.
3012 switch (trust = check_dane_issuer(ctx, ctx->num_untrusted - 1)) {
3013 case X509_TRUST_TRUSTED:
3014 case X509_TRUST_REJECTED:
3020 sk_X509_free(sktmp);
3023 * Last chance to make a trusted chain, either bare DANE-TA public-key
3024 * signers, or else direct leaf PKIX trust.
3026 num = sk_X509_num(ctx->chain);
3028 if (trust == X509_TRUST_UNTRUSTED && DANETLS_HAS_DANE_TA(dane))
3029 trust = check_dane_pkeys(ctx);
3030 if (trust == X509_TRUST_UNTRUSTED && num == ctx->num_untrusted)
3031 trust = check_trust(ctx, num);
3035 case X509_TRUST_TRUSTED:
3037 case X509_TRUST_REJECTED:
3038 /* Callback already issued */
3040 case X509_TRUST_UNTRUSTED:
3042 num = sk_X509_num(ctx->chain);
3044 return verify_cb_cert(ctx, NULL, num-1,
3045 X509_V_ERR_CERT_CHAIN_TOO_LONG);
3046 if (DANETLS_ENABLED(dane) &&
3047 (!DANETLS_HAS_PKIX(dane) || dane->pdpth >= 0))
3048 return verify_cb_cert(ctx, NULL, num-1, X509_V_ERR_DANE_NO_MATCH);
3049 if (ss && sk_X509_num(ctx->chain) == 1)
3050 return verify_cb_cert(ctx, NULL, num-1,
3051 X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT);
3053 return verify_cb_cert(ctx, NULL, num-1,
3054 X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN);
3055 if (ctx->num_untrusted < num)
3056 return verify_cb_cert(ctx, NULL, num-1,
3057 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT);
3058 return verify_cb_cert(ctx, NULL, num-1,
3059 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY);
3063 static const int minbits_table[] = { 80, 112, 128, 192, 256 };
3064 static const int NUM_AUTH_LEVELS = OSSL_NELEM(minbits_table);
3067 * Check whether the public key of ``cert`` meets the security level of
3070 * Returns 1 on success, 0 otherwise.
3072 static int check_key_level(X509_STORE_CTX *ctx, X509 *cert)
3074 EVP_PKEY *pkey = X509_get0_pubkey(cert);
3075 int level = ctx->param->auth_level;
3077 /* Unsupported or malformed keys are not secure */
3083 if (level > NUM_AUTH_LEVELS)
3084 level = NUM_AUTH_LEVELS;
3086 return EVP_PKEY_security_bits(pkey) >= minbits_table[level - 1];
3090 * Check whether the signature digest algorithm of ``cert`` meets the security
3091 * level of ``ctx``. Should not be checked for trust anchors (whether
3092 * self-signed or otherwise).
3094 * Returns 1 on success, 0 otherwise.
3096 static int check_sig_level(X509_STORE_CTX *ctx, X509 *cert)
3098 int nid = X509_get_signature_nid(cert);
3099 int mdnid = NID_undef;
3101 int level = ctx->param->auth_level;
3105 if (level > NUM_AUTH_LEVELS)
3106 level = NUM_AUTH_LEVELS;
3108 /* Lookup signature algorithm digest */
3109 if (nid && OBJ_find_sigid_algs(nid, &mdnid, NULL)) {
3112 /* Assume 4 bits of collision resistance for each hash octet */
3113 if (mdnid != NID_undef && (md = EVP_get_digestbynid(mdnid)) != NULL)
3114 secbits = EVP_MD_size(md) * 4;
3117 return secbits >= minbits_table[level - 1];