/* * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL project * 2001. */ /* ==================================================================== * Copyright (c) 1999-2004 The OpenSSL Project. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * * 3. All advertising materials mentioning features or use of this * software must display the following acknowledgment: * "This product includes software developed by the OpenSSL Project * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)" * * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to * endorse or promote products derived from this software without * prior written permission. For written permission, please contact * licensing@OpenSSL.org. * * 5. Products derived from this software may not be called "OpenSSL" * nor may "OpenSSL" appear in their names without prior written * permission of the OpenSSL Project. * * 6. Redistributions of any form whatsoever must retain the following * acknowledgment: * "This product includes software developed by the OpenSSL Project * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)" * * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED * OF THE POSSIBILITY OF SUCH DAMAGE. * ==================================================================== * * This product includes cryptographic software written by Eric Young * (eay@cryptsoft.com). This product includes software written by Tim * Hudson (tjh@cryptsoft.com). */ #include #include #include #include #include #include #include #include #include "../internal.h" #include "../x509/internal.h" #include "internal.h" #define V1_ROOT (EXFLAG_V1 | EXFLAG_SS) #define ku_reject(x, usage) \ (((x)->ex_flags & EXFLAG_KUSAGE) && !((x)->ex_kusage & (usage))) #define xku_reject(x, usage) \ (((x)->ex_flags & EXFLAG_XKUSAGE) && !((x)->ex_xkusage & (usage))) #define ns_reject(x, usage) \ (((x)->ex_flags & EXFLAG_NSCERT) && !((x)->ex_nscert & (usage))) static int check_purpose_ssl_client(const X509_PURPOSE *xp, const X509 *x, int ca); static int check_purpose_ssl_server(const X509_PURPOSE *xp, const X509 *x, int ca); static int check_purpose_ns_ssl_server(const X509_PURPOSE *xp, const X509 *x, int ca); static int purpose_smime(const X509 *x, int ca); static int check_purpose_smime_sign(const X509_PURPOSE *xp, const X509 *x, int ca); static int check_purpose_smime_encrypt(const X509_PURPOSE *xp, const X509 *x, int ca); static int check_purpose_crl_sign(const X509_PURPOSE *xp, const X509 *x, int ca); static int check_purpose_timestamp_sign(const X509_PURPOSE *xp, const X509 *x, int ca); static int no_check(const X509_PURPOSE *xp, const X509 *x, int ca); static int ocsp_helper(const X509_PURPOSE *xp, const X509 *x, int ca); static int xp_cmp(const X509_PURPOSE *const *a, const X509_PURPOSE *const *b); static void xptable_free(X509_PURPOSE *p); static X509_PURPOSE xstandard[] = { {X509_PURPOSE_SSL_CLIENT, X509_TRUST_SSL_CLIENT, 0, check_purpose_ssl_client, (char *)"SSL client", (char *)"sslclient", NULL}, {X509_PURPOSE_SSL_SERVER, X509_TRUST_SSL_SERVER, 0, check_purpose_ssl_server, (char *)"SSL server", (char *)"sslserver", NULL}, {X509_PURPOSE_NS_SSL_SERVER, X509_TRUST_SSL_SERVER, 0, check_purpose_ns_ssl_server, (char *)"Netscape SSL server", (char *)"nssslserver", NULL}, {X509_PURPOSE_SMIME_SIGN, X509_TRUST_EMAIL, 0, check_purpose_smime_sign, (char *)"S/MIME signing", (char *)"smimesign", NULL}, {X509_PURPOSE_SMIME_ENCRYPT, X509_TRUST_EMAIL, 0, check_purpose_smime_encrypt, (char *)"S/MIME encryption", (char *)"smimeencrypt", NULL}, {X509_PURPOSE_CRL_SIGN, X509_TRUST_COMPAT, 0, check_purpose_crl_sign, (char *)"CRL signing", (char *)"crlsign", NULL}, {X509_PURPOSE_ANY, X509_TRUST_DEFAULT, 0, no_check, (char *)"Any Purpose", (char *)"any", NULL}, {X509_PURPOSE_OCSP_HELPER, X509_TRUST_COMPAT, 0, ocsp_helper, (char *)"OCSP helper", (char *)"ocsphelper", NULL}, {X509_PURPOSE_TIMESTAMP_SIGN, X509_TRUST_TSA, 0, check_purpose_timestamp_sign, (char *)"Time Stamp signing", (char *)"timestampsign", NULL}, }; #define X509_PURPOSE_COUNT (sizeof(xstandard) / sizeof(X509_PURPOSE)) static STACK_OF(X509_PURPOSE) *xptable = NULL; static int xp_cmp(const X509_PURPOSE *const *a, const X509_PURPOSE *const *b) { return (*a)->purpose - (*b)->purpose; } // As much as I'd like to make X509_check_purpose use a "const" X509* I // really can't because it does recalculate hashes and do other non-const // things. int X509_check_purpose(X509 *x, int id, int ca) { int idx; const X509_PURPOSE *pt; if (!x509v3_cache_extensions(x)) { return -1; } if (id == -1) { return 1; } idx = X509_PURPOSE_get_by_id(id); if (idx == -1) { return -1; } pt = X509_PURPOSE_get0(idx); return pt->check_purpose(pt, x, ca); } int X509_PURPOSE_set(int *p, int purpose) { if (X509_PURPOSE_get_by_id(purpose) == -1) { OPENSSL_PUT_ERROR(X509V3, X509V3_R_INVALID_PURPOSE); return 0; } *p = purpose; return 1; } int X509_PURPOSE_get_count(void) { if (!xptable) { return X509_PURPOSE_COUNT; } return sk_X509_PURPOSE_num(xptable) + X509_PURPOSE_COUNT; } X509_PURPOSE *X509_PURPOSE_get0(int idx) { if (idx < 0) { return NULL; } if (idx < (int)X509_PURPOSE_COUNT) { return xstandard + idx; } return sk_X509_PURPOSE_value(xptable, idx - X509_PURPOSE_COUNT); } int X509_PURPOSE_get_by_sname(char *sname) { int i; X509_PURPOSE *xptmp; for (i = 0; i < X509_PURPOSE_get_count(); i++) { xptmp = X509_PURPOSE_get0(i); if (!strcmp(xptmp->sname, sname)) { return i; } } return -1; } int X509_PURPOSE_get_by_id(int purpose) { X509_PURPOSE tmp; size_t idx; if ((purpose >= X509_PURPOSE_MIN) && (purpose <= X509_PURPOSE_MAX)) { return purpose - X509_PURPOSE_MIN; } tmp.purpose = purpose; if (!xptable) { return -1; } if (!sk_X509_PURPOSE_find(xptable, &idx, &tmp)) { return -1; } return idx + X509_PURPOSE_COUNT; } int X509_PURPOSE_add(int id, int trust, int flags, int (*ck)(const X509_PURPOSE *, const X509 *, int), char *name, char *sname, void *arg) { int idx; X509_PURPOSE *ptmp; char *name_dup, *sname_dup; // This is set according to what we change: application can't set it flags &= ~X509_PURPOSE_DYNAMIC; // This will always be set for application modified trust entries flags |= X509_PURPOSE_DYNAMIC_NAME; // Get existing entry if any idx = X509_PURPOSE_get_by_id(id); // Need a new entry if (idx == -1) { if (!(ptmp = OPENSSL_malloc(sizeof(X509_PURPOSE)))) { return 0; } ptmp->flags = X509_PURPOSE_DYNAMIC; } else { ptmp = X509_PURPOSE_get0(idx); } // Duplicate the supplied names. name_dup = OPENSSL_strdup(name); sname_dup = OPENSSL_strdup(sname); if (name_dup == NULL || sname_dup == NULL) { if (name_dup != NULL) { OPENSSL_free(name_dup); } if (sname_dup != NULL) { OPENSSL_free(sname_dup); } if (idx == -1) { OPENSSL_free(ptmp); } return 0; } // OPENSSL_free existing name if dynamic if (ptmp->flags & X509_PURPOSE_DYNAMIC_NAME) { OPENSSL_free(ptmp->name); OPENSSL_free(ptmp->sname); } // dup supplied name ptmp->name = name_dup; ptmp->sname = sname_dup; // Keep the dynamic flag of existing entry ptmp->flags &= X509_PURPOSE_DYNAMIC; // Set all other flags ptmp->flags |= flags; ptmp->purpose = id; ptmp->trust = trust; ptmp->check_purpose = ck; ptmp->usr_data = arg; // If its a new entry manage the dynamic table if (idx == -1) { // TODO(davidben): This should be locked. Alternatively, remove the dynamic // registration mechanism entirely. The trouble is there no way to pass in // the various parameters into an |X509_VERIFY_PARAM| directly. You can only // register it in the global table and get an ID. if (!xptable && !(xptable = sk_X509_PURPOSE_new(xp_cmp))) { xptable_free(ptmp); return 0; } if (!sk_X509_PURPOSE_push(xptable, ptmp)) { xptable_free(ptmp); return 0; } sk_X509_PURPOSE_sort(xptable); } return 1; } static void xptable_free(X509_PURPOSE *p) { if (!p) { return; } if (p->flags & X509_PURPOSE_DYNAMIC) { if (p->flags & X509_PURPOSE_DYNAMIC_NAME) { OPENSSL_free(p->name); OPENSSL_free(p->sname); } OPENSSL_free(p); } } void X509_PURPOSE_cleanup(void) { unsigned int i; sk_X509_PURPOSE_pop_free(xptable, xptable_free); for (i = 0; i < X509_PURPOSE_COUNT; i++) { xptable_free(xstandard + i); } xptable = NULL; } int X509_PURPOSE_get_id(const X509_PURPOSE *xp) { return xp->purpose; } char *X509_PURPOSE_get0_name(const X509_PURPOSE *xp) { return xp->name; } char *X509_PURPOSE_get0_sname(const X509_PURPOSE *xp) { return xp->sname; } int X509_PURPOSE_get_trust(const X509_PURPOSE *xp) { return xp->trust; } static int nid_cmp(const void *void_a, const void *void_b) { const int *a = void_a, *b = void_b; return *a - *b; } int X509_supported_extension(const X509_EXTENSION *ex) { // This table is a list of the NIDs of supported extensions: that is // those which are used by the verify process. If an extension is // critical and doesn't appear in this list then the verify process will // normally reject the certificate. The list must be kept in numerical // order because it will be searched using bsearch. static const int supported_nids[] = { NID_netscape_cert_type, // 71 NID_key_usage, // 83 NID_subject_alt_name, // 85 NID_basic_constraints, // 87 NID_certificate_policies, // 89 NID_ext_key_usage, // 126 NID_policy_constraints, // 401 NID_name_constraints, // 666 NID_policy_mappings, // 747 NID_inhibit_any_policy // 748 }; int ex_nid = OBJ_obj2nid(X509_EXTENSION_get_object(ex)); if (ex_nid == NID_undef) { return 0; } if (bsearch(&ex_nid, supported_nids, sizeof(supported_nids) / sizeof(int), sizeof(int), nid_cmp) != NULL) { return 1; } return 0; } static int setup_dp(X509 *x, DIST_POINT *dp) { X509_NAME *iname = NULL; size_t i; if (dp->reasons) { if (dp->reasons->length > 0) { dp->dp_reasons = dp->reasons->data[0]; } if (dp->reasons->length > 1) { dp->dp_reasons |= (dp->reasons->data[1] << 8); } dp->dp_reasons &= CRLDP_ALL_REASONS; } else { dp->dp_reasons = CRLDP_ALL_REASONS; } if (!dp->distpoint || (dp->distpoint->type != 1)) { return 1; } for (i = 0; i < sk_GENERAL_NAME_num(dp->CRLissuer); i++) { GENERAL_NAME *gen = sk_GENERAL_NAME_value(dp->CRLissuer, i); if (gen->type == GEN_DIRNAME) { iname = gen->d.directoryName; break; } } if (!iname) { iname = X509_get_issuer_name(x); } return DIST_POINT_set_dpname(dp->distpoint, iname); } static int setup_crldp(X509 *x) { int j; x->crldp = X509_get_ext_d2i(x, NID_crl_distribution_points, &j, NULL); if (x->crldp == NULL && j != -1) { return 0; } for (size_t i = 0; i < sk_DIST_POINT_num(x->crldp); i++) { if (!setup_dp(x, sk_DIST_POINT_value(x->crldp, i))) { return 0; } } return 1; } int x509v3_cache_extensions(X509 *x) { BASIC_CONSTRAINTS *bs; ASN1_BIT_STRING *usage; ASN1_BIT_STRING *ns; EXTENDED_KEY_USAGE *extusage; size_t i; int j; CRYPTO_MUTEX_lock_read(&x->lock); const int is_set = x->ex_flags & EXFLAG_SET; CRYPTO_MUTEX_unlock_read(&x->lock); if (is_set) { return (x->ex_flags & EXFLAG_INVALID) == 0; } CRYPTO_MUTEX_lock_write(&x->lock); if (x->ex_flags & EXFLAG_SET) { CRYPTO_MUTEX_unlock_write(&x->lock); return (x->ex_flags & EXFLAG_INVALID) == 0; } if (!X509_digest(x, EVP_sha256(), x->cert_hash, NULL)) { x->ex_flags |= EXFLAG_INVALID; } // V1 should mean no extensions ... if (X509_get_version(x) == X509_VERSION_1) { x->ex_flags |= EXFLAG_V1; } // Handle basic constraints if ((bs = X509_get_ext_d2i(x, NID_basic_constraints, &j, NULL))) { if (bs->ca) { x->ex_flags |= EXFLAG_CA; } if (bs->pathlen) { if ((bs->pathlen->type == V_ASN1_NEG_INTEGER) || !bs->ca) { x->ex_flags |= EXFLAG_INVALID; x->ex_pathlen = 0; } else { // TODO(davidben): |ASN1_INTEGER_get| returns -1 on overflow, // which currently acts as if the constraint isn't present. This // works (an overflowing path length constraint may as well be // infinity), but Chromium's verifier simply treats values above // 255 as an error. x->ex_pathlen = ASN1_INTEGER_get(bs->pathlen); } } else { x->ex_pathlen = -1; } BASIC_CONSTRAINTS_free(bs); x->ex_flags |= EXFLAG_BCONS; } else if (j != -1) { x->ex_flags |= EXFLAG_INVALID; } // Handle key usage if ((usage = X509_get_ext_d2i(x, NID_key_usage, &j, NULL))) { if (usage->length > 0) { x->ex_kusage = usage->data[0]; if (usage->length > 1) { x->ex_kusage |= usage->data[1] << 8; } } else { x->ex_kusage = 0; } x->ex_flags |= EXFLAG_KUSAGE; ASN1_BIT_STRING_free(usage); } else if (j != -1) { x->ex_flags |= EXFLAG_INVALID; } x->ex_xkusage = 0; if ((extusage = X509_get_ext_d2i(x, NID_ext_key_usage, &j, NULL))) { x->ex_flags |= EXFLAG_XKUSAGE; for (i = 0; i < sk_ASN1_OBJECT_num(extusage); i++) { switch (OBJ_obj2nid(sk_ASN1_OBJECT_value(extusage, i))) { case NID_server_auth: x->ex_xkusage |= XKU_SSL_SERVER; break; case NID_client_auth: x->ex_xkusage |= XKU_SSL_CLIENT; break; case NID_email_protect: x->ex_xkusage |= XKU_SMIME; break; case NID_code_sign: x->ex_xkusage |= XKU_CODE_SIGN; break; case NID_ms_sgc: case NID_ns_sgc: x->ex_xkusage |= XKU_SGC; break; case NID_OCSP_sign: x->ex_xkusage |= XKU_OCSP_SIGN; break; case NID_time_stamp: x->ex_xkusage |= XKU_TIMESTAMP; break; case NID_dvcs: x->ex_xkusage |= XKU_DVCS; break; case NID_anyExtendedKeyUsage: x->ex_xkusage |= XKU_ANYEKU; break; } } sk_ASN1_OBJECT_pop_free(extusage, ASN1_OBJECT_free); } else if (j != -1) { x->ex_flags |= EXFLAG_INVALID; } if ((ns = X509_get_ext_d2i(x, NID_netscape_cert_type, &j, NULL))) { if (ns->length > 0) { x->ex_nscert = ns->data[0]; } else { x->ex_nscert = 0; } x->ex_flags |= EXFLAG_NSCERT; ASN1_BIT_STRING_free(ns); } else if (j != -1) { x->ex_flags |= EXFLAG_INVALID; } x->skid = X509_get_ext_d2i(x, NID_subject_key_identifier, &j, NULL); if (x->skid == NULL && j != -1) { x->ex_flags |= EXFLAG_INVALID; } x->akid = X509_get_ext_d2i(x, NID_authority_key_identifier, &j, NULL); if (x->akid == NULL && j != -1) { x->ex_flags |= EXFLAG_INVALID; } // Does subject name match issuer ? if (!X509_NAME_cmp(X509_get_subject_name(x), X509_get_issuer_name(x))) { x->ex_flags |= EXFLAG_SI; // If SKID matches AKID also indicate self signed if (X509_check_akid(x, x->akid) == X509_V_OK && !ku_reject(x, KU_KEY_CERT_SIGN)) { x->ex_flags |= EXFLAG_SS; } } x->altname = X509_get_ext_d2i(x, NID_subject_alt_name, &j, NULL); if (x->altname == NULL && j != -1) { x->ex_flags |= EXFLAG_INVALID; } x->nc = X509_get_ext_d2i(x, NID_name_constraints, &j, NULL); if (x->nc == NULL && j != -1) { x->ex_flags |= EXFLAG_INVALID; } if (!setup_crldp(x)) { x->ex_flags |= EXFLAG_INVALID; } for (j = 0; j < X509_get_ext_count(x); j++) { const X509_EXTENSION *ex = X509_get_ext(x, j); if (OBJ_obj2nid(X509_EXTENSION_get_object(ex)) == NID_freshest_crl) { x->ex_flags |= EXFLAG_FRESHEST; } if (!X509_EXTENSION_get_critical(ex)) { continue; } if (!X509_supported_extension(ex)) { x->ex_flags |= EXFLAG_CRITICAL; break; } } x->ex_flags |= EXFLAG_SET; CRYPTO_MUTEX_unlock_write(&x->lock); return (x->ex_flags & EXFLAG_INVALID) == 0; } // check_ca returns one if |x| should be considered a CA certificate and zero // otherwise. static int check_ca(const X509 *x) { // keyUsage if present should allow cert signing if (ku_reject(x, KU_KEY_CERT_SIGN)) { return 0; } // Version 1 certificates are considered CAs and don't have extensions. if ((x->ex_flags & V1_ROOT) == V1_ROOT) { return 1; } // Otherwise, it's only a CA if basicConstraints says so. return ((x->ex_flags & EXFLAG_BCONS) && (x->ex_flags & EXFLAG_CA)); } int X509_check_ca(X509 *x) { if (!x509v3_cache_extensions(x)) { return 0; } return check_ca(x); } static int check_purpose_ssl_client(const X509_PURPOSE *xp, const X509 *x, int ca) { if (xku_reject(x, XKU_SSL_CLIENT)) { return 0; } if (ca) { return check_ca(x); } // We need to do digital signatures or key agreement if (ku_reject(x, KU_DIGITAL_SIGNATURE | KU_KEY_AGREEMENT)) { return 0; } // nsCertType if present should allow SSL client use if (ns_reject(x, NS_SSL_CLIENT)) { return 0; } return 1; } // Key usage needed for TLS/SSL server: digital signature, encipherment or // key agreement. The ssl code can check this more thoroughly for individual // key types. #define KU_TLS (KU_DIGITAL_SIGNATURE | KU_KEY_ENCIPHERMENT | KU_KEY_AGREEMENT) static int check_purpose_ssl_server(const X509_PURPOSE *xp, const X509 *x, int ca) { if (xku_reject(x, XKU_SSL_SERVER)) { return 0; } if (ca) { return check_ca(x); } if (ns_reject(x, NS_SSL_SERVER)) { return 0; } if (ku_reject(x, KU_TLS)) { return 0; } return 1; } static int check_purpose_ns_ssl_server(const X509_PURPOSE *xp, const X509 *x, int ca) { int ret; ret = check_purpose_ssl_server(xp, x, ca); if (!ret || ca) { return ret; } // We need to encipher or Netscape complains if (ku_reject(x, KU_KEY_ENCIPHERMENT)) { return 0; } return ret; } // purpose_smime returns one if |x| is a valid S/MIME leaf (|ca| is zero) or CA // (|ca| is one) certificate, and zero otherwise. static int purpose_smime(const X509 *x, int ca) { if (xku_reject(x, XKU_SMIME)) { return 0; } if (ca) { // check nsCertType if present if ((x->ex_flags & EXFLAG_NSCERT) && (x->ex_nscert & NS_SMIME_CA) == 0) { return 0; } return check_ca(x); } if (x->ex_flags & EXFLAG_NSCERT) { return (x->ex_nscert & NS_SMIME) == NS_SMIME; } return 1; } static int check_purpose_smime_sign(const X509_PURPOSE *xp, const X509 *x, int ca) { int ret; ret = purpose_smime(x, ca); if (!ret || ca) { return ret; } if (ku_reject(x, KU_DIGITAL_SIGNATURE | KU_NON_REPUDIATION)) { return 0; } return ret; } static int check_purpose_smime_encrypt(const X509_PURPOSE *xp, const X509 *x, int ca) { int ret; ret = purpose_smime(x, ca); if (!ret || ca) { return ret; } if (ku_reject(x, KU_KEY_ENCIPHERMENT)) { return 0; } return ret; } static int check_purpose_crl_sign(const X509_PURPOSE *xp, const X509 *x, int ca) { if (ca) { return check_ca(x); } if (ku_reject(x, KU_CRL_SIGN)) { return 0; } return 1; } // OCSP helper: this is *not* a full OCSP check. It just checks that each CA // is valid. Additional checks must be made on the chain. static int ocsp_helper(const X509_PURPOSE *xp, const X509 *x, int ca) { if (ca) { return check_ca(x); } // leaf certificate is checked in OCSP_verify() return 1; } static int check_purpose_timestamp_sign(const X509_PURPOSE *xp, const X509 *x, int ca) { int i_ext; // If ca is true we must return if this is a valid CA certificate. if (ca) { return check_ca(x); } // Check the optional key usage field: // if Key Usage is present, it must be one of digitalSignature // and/or nonRepudiation (other values are not consistent and shall // be rejected). if ((x->ex_flags & EXFLAG_KUSAGE) && ((x->ex_kusage & ~(KU_NON_REPUDIATION | KU_DIGITAL_SIGNATURE)) || !(x->ex_kusage & (KU_NON_REPUDIATION | KU_DIGITAL_SIGNATURE)))) { return 0; } // Only time stamp key usage is permitted and it's required. if (!(x->ex_flags & EXFLAG_XKUSAGE) || x->ex_xkusage != XKU_TIMESTAMP) { return 0; } // Extended Key Usage MUST be critical i_ext = X509_get_ext_by_NID((X509 *)x, NID_ext_key_usage, -1); if (i_ext >= 0) { const X509_EXTENSION *ext = X509_get_ext((X509 *)x, i_ext); if (!X509_EXTENSION_get_critical(ext)) { return 0; } } return 1; } static int no_check(const X509_PURPOSE *xp, const X509 *x, int ca) { return 1; } // Various checks to see if one certificate issued the second. This can be // used to prune a set of possible issuer certificates which have been looked // up using some simple method such as by subject name. These are: 1. Check // issuer_name(subject) == subject_name(issuer) 2. If akid(subject) exists // check it matches issuer 3. If key_usage(issuer) exists check it supports // certificate signing returns 0 for OK, positive for reason for mismatch, // reasons match codes for X509_verify_cert() int X509_check_issued(X509 *issuer, X509 *subject) { if (X509_NAME_cmp(X509_get_subject_name(issuer), X509_get_issuer_name(subject))) { return X509_V_ERR_SUBJECT_ISSUER_MISMATCH; } if (!x509v3_cache_extensions(issuer) || !x509v3_cache_extensions(subject)) { return X509_V_ERR_UNSPECIFIED; } if (subject->akid) { int ret = X509_check_akid(issuer, subject->akid); if (ret != X509_V_OK) { return ret; } } if (ku_reject(issuer, KU_KEY_CERT_SIGN)) { return X509_V_ERR_KEYUSAGE_NO_CERTSIGN; } return X509_V_OK; } int X509_check_akid(X509 *issuer, AUTHORITY_KEYID *akid) { if (!akid) { return X509_V_OK; } // Check key ids (if present) if (akid->keyid && issuer->skid && ASN1_OCTET_STRING_cmp(akid->keyid, issuer->skid)) { return X509_V_ERR_AKID_SKID_MISMATCH; } // Check serial number if (akid->serial && ASN1_INTEGER_cmp(X509_get_serialNumber(issuer), akid->serial)) { return X509_V_ERR_AKID_ISSUER_SERIAL_MISMATCH; } // Check issuer name if (akid->issuer) { // Ugh, for some peculiar reason AKID includes SEQUENCE OF // GeneralName. So look for a DirName. There may be more than one but // we only take any notice of the first. GENERAL_NAMES *gens; GENERAL_NAME *gen; X509_NAME *nm = NULL; size_t i; gens = akid->issuer; for (i = 0; i < sk_GENERAL_NAME_num(gens); i++) { gen = sk_GENERAL_NAME_value(gens, i); if (gen->type == GEN_DIRNAME) { nm = gen->d.dirn; break; } } if (nm && X509_NAME_cmp(nm, X509_get_issuer_name(issuer))) { return X509_V_ERR_AKID_ISSUER_SERIAL_MISMATCH; } } return X509_V_OK; } uint32_t X509_get_extension_flags(X509 *x) { // Ignore the return value. On failure, |x->ex_flags| will include // |EXFLAG_INVALID|. x509v3_cache_extensions(x); return x->ex_flags; } uint32_t X509_get_key_usage(X509 *x) { if (!x509v3_cache_extensions(x)) { return 0; } if (x->ex_flags & EXFLAG_KUSAGE) { return x->ex_kusage; } return UINT32_MAX; } uint32_t X509_get_extended_key_usage(X509 *x) { if (!x509v3_cache_extensions(x)) { return 0; } if (x->ex_flags & EXFLAG_XKUSAGE) { return x->ex_xkusage; } return UINT32_MAX; } const ASN1_OCTET_STRING *X509_get0_subject_key_id(X509 *x509) { if (!x509v3_cache_extensions(x509)) { return NULL; } return x509->skid; } const ASN1_OCTET_STRING *X509_get0_authority_key_id(X509 *x509) { if (!x509v3_cache_extensions(x509)) { return NULL; } return x509->akid != NULL ? x509->akid->keyid : NULL; } const GENERAL_NAMES *X509_get0_authority_issuer(X509 *x509) { if (!x509v3_cache_extensions(x509)) { return NULL; } return x509->akid != NULL ? x509->akid->issuer : NULL; } const ASN1_INTEGER *X509_get0_authority_serial(X509 *x509) { if (!x509v3_cache_extensions(x509)) { return NULL; } return x509->akid != NULL ? x509->akid->serial : NULL; } long X509_get_pathlen(X509 *x509) { if (!x509v3_cache_extensions(x509) || (x509->ex_flags & EXFLAG_BCONS) == 0) { return -1; } return x509->ex_pathlen; }