+static int do_x509_check(X509 *x, const char *chk, size_t chklen,
+ unsigned int flags, int check_type, char **peername)
+{
+ GENERAL_NAMES *gens = NULL;
+ X509_NAME *name = NULL;
+ int i;
+ int cnid = NID_undef;
+ int alt_type;
+ int san_present = 0;
+ int rv = 0;
+ equal_fn equal;
+
+ /* See below, this flag is internal-only */
+ flags &= ~_X509_CHECK_FLAG_DOT_SUBDOMAINS;
+ if (check_type == GEN_EMAIL) {
+ cnid = NID_pkcs9_emailAddress;
+ alt_type = V_ASN1_IA5STRING;
+ equal = equal_email;
+ } else if (check_type == GEN_DNS) {
+ cnid = NID_commonName;
+ /* Implicit client-side DNS sub-domain pattern */
+ if (chklen > 1 && chk[0] == '.')
+ flags |= _X509_CHECK_FLAG_DOT_SUBDOMAINS;
+ alt_type = V_ASN1_IA5STRING;
+ if (flags & X509_CHECK_FLAG_NO_WILDCARDS)
+ equal = equal_nocase;
+ else
+ equal = equal_wildcard;
+ } else {
+ alt_type = V_ASN1_OCTET_STRING;
+ equal = equal_case;
+ }
+
+ if (chklen == 0)
+ chklen = strlen(chk);
+
+ gens = X509_get_ext_d2i(x, NID_subject_alt_name, NULL, NULL);
+ if (gens) {
+ for (i = 0; i < sk_GENERAL_NAME_num(gens); i++) {
+ GENERAL_NAME *gen;
+ ASN1_STRING *cstr;
+ gen = sk_GENERAL_NAME_value(gens, i);
+ if (gen->type != check_type)
+ continue;
+ san_present = 1;
+ if (check_type == GEN_EMAIL)
+ cstr = gen->d.rfc822Name;
+ else if (check_type == GEN_DNS)
+ cstr = gen->d.dNSName;
+ else
+ cstr = gen->d.iPAddress;
+ /* Positive on success, negative on error! */
+ if ((rv = do_check_string(cstr, alt_type, equal, flags,
+ chk, chklen, peername)) != 0)
+ break;
+ }
+ GENERAL_NAMES_free(gens);
+ if (rv != 0)
+ return rv;
+ if (san_present && !(flags & X509_CHECK_FLAG_ALWAYS_CHECK_SUBJECT))
+ return 0;
+ }
+
+ /* We're done if CN-ID is not pertinent */
+ if (cnid == NID_undef || (flags & X509_CHECK_FLAG_NEVER_CHECK_SUBJECT))
+ return 0;
+
+ i = -1;
+ name = X509_get_subject_name(x);
+ while ((i = X509_NAME_get_index_by_NID(name, cnid, i)) >= 0) {
+ X509_NAME_ENTRY *ne;
+ ASN1_STRING *str;
+ ne = X509_NAME_get_entry(name, i);
+ str = X509_NAME_ENTRY_get_data(ne);
+ /* Positive on success, negative on error! */
+ if ((rv = do_check_string(str, -1, equal, flags,
+ chk, chklen, peername)) != 0)
+ return rv;
+ }
+ return 0;
+}