add restriction to excluded DIR name constraint

certs/test/cert-ext-ndir-exc.cfg

@@ -0,0 +1,24 @@
+[ req ]
+distinguished_name = req_distinguished_name
+prompt             = no
+x509_extensions    = constraints
+
+[ req_distinguished_name ]
+C             = US
+ST            = Montana
+L             = Bozeman
+O             = Sawtooth
+OU            = Consulting
+CN            = www.wolfssl.com
+emailAddress  = info@wolfsssl.com
+
+[constraints]
+subjectKeyIdentifier=hash
+authorityKeyIdentifier=keyid:always,issuer:always
+basicConstraints=CA:TRUE
+nameConstraints=critical,excluded;dirName:dir_name_exclude
+
+[dir_name_exclude]
+countryName = US
+stateOrProvinceName = California
+

certs/test/gen-ext-certs.sh

@@ -128,3 +128,35 @@ countryName = US
 EOF
 gen_cert
 
+OUT=certs/test/cert-ext-ndir-exc.der
+KEYFILE=certs/ca-key.der
+CONFIG=certs/test/cert-ext-ndir-exc.cfg
+tee >$CONFIG <<EOF
+[ req ]
+distinguished_name = req_distinguished_name
+prompt             = no
+x509_extensions    = constraints
+
+[ req_distinguished_name ]
+C             = US
+ST            = Montana
+L             = Bozeman
+O             = Sawtooth
+OU            = Consulting
+CN            = www.wolfssl.com
+emailAddress  = info@wolfsssl.com
+
+[constraints]
+subjectKeyIdentifier=hash
+authorityKeyIdentifier=keyid:always,issuer:always
+basicConstraints=CA:TRUE
+nameConstraints=critical,excluded;dirName:dir_name_exclude
+
+[dir_name_exclude]
+countryName = US
+stateOrProvinceName = California
+
+EOF
+gen_cert
+
+

certs/test/include.am

@@ -12,6 +12,8 @@ EXTRA_DIST += \
          certs/test/cert-ext-ndir.cfg \
          certs/test/cert-ext-ndir.der \
          certs/test/cert-ext-ns.der \
+         certs/test/cert-ext-ndir-exc.cfg \
+         certs/test/cert-ext-ndir-exc.der \
          certs/test/gen-ext-certs.sh \
          certs/test/server-duplicate-policy.pem \
          certs/test/cert-ext-joi.pem

tests/api.c

@@ -1274,7 +1274,8 @@ static void test_wolfSSL_CertManagerNameConstraint2(void)
     !defined(NO_WOLFSSL_CM_VERIFY) && !defined(NO_RSA) && \
     defined(OPENSSL_EXTRA) && defined(WOLFSSL_CERT_GEN) && \
     defined(WOLFSSL_CERT_EXT) && defined(WOLFSSL_ALT_NAMES)
-    const char* ca_cert = "./certs/test/cert-ext-ndir.der";
+    const char* ca_cert  = "./certs/test/cert-ext-ndir.der";
+    const char* ca_cert2 = "./certs/test/cert-ext-ndir-exc.der";
     const char* server_cert = "./certs/server-cert.pem";
     WOLFSSL_CERT_MANAGER* cm;
     WOLFSSL_X509 *x509, *ca;
@@ -1297,6 +1298,15 @@ static void test_wolfSSL_CertManagerNameConstraint2(void)
         0x06, 0x03, 0x55, 0x04, 0x06, 0x13, 0x02, 0x49, 0x44
     };
 
+    /* C=US ST=California*/
+    char altNameExc[] = {
+        0x30, 0x22,
+        0x31, 0x0B,
+        0x30, 0x09, 0x06, 0x03, 0x55, 0x04, 0x06, 0x13, 0x02, 0x55, 0x53,
+        0x31, 0x13,
+        0x30, 0x11, 0x06, 0x03, 0x55, 0x04, 0x08, 0x0C, 0x0A,
+        0x43, 0x61, 0x6c, 0x69, 0x66, 0x6f, 0x72, 0x6e, 0x69, 0x61
+    };
     /* load in CA private key for signing */
     pt = ca_key_der_2048;
     AssertNotNull(priv = wolfSSL_d2i_PrivateKey(EVP_PKEY_RSA, NULL, &pt,
@@ -1337,7 +1347,6 @@ static void test_wolfSSL_CertManagerNameConstraint2(void)
     wolfSSL_X509_add_altname_ex(x509, altNameFail, sizeof(altNameFail),
             ASN_DIR_TYPE);
 
-
     wolfSSL_X509_sign(x509, priv, EVP_sha256());
     AssertNotNull((der = wolfSSL_X509_get_der(x509, &derSz)));
     AssertIntEQ(wolfSSL_CertManagerVerifyBuffer(cm, der, derSz,
@@ -1346,7 +1355,30 @@ static void test_wolfSSL_CertManagerNameConstraint2(void)
 
     wolfSSL_X509_free(x509);
     wolfSSL_X509_free(ca);
-    wolfSSL_X509_MAME_free(name);
+
+    /* now test with excluded name constraint */
+    AssertNotNull(cm = wolfSSL_CertManagerNew());
+    AssertNotNull(ca = wolfSSL_X509_load_certificate_file(ca_cert2,
+                WOLFSSL_FILETYPE_ASN1));
+    AssertNotNull((der = wolfSSL_X509_get_der(ca, &derSz)));
+    AssertIntEQ(wolfSSL_CertManagerLoadCABuffer(cm, der, derSz,
+                WOLFSSL_FILETYPE_ASN1), WOLFSSL_SUCCESS);
+
+    AssertNotNull(x509 = wolfSSL_X509_load_certificate_file(server_cert,
+                WOLFSSL_FILETYPE_PEM));
+    wolfSSL_X509_add_altname_ex(x509, altNameExc, sizeof(altNameExc),
+            ASN_DIR_TYPE);
+    AssertNotNull(name = wolfSSL_X509_get_subject_name(ca));
+    AssertIntEQ(wolfSSL_X509_set_issuer_name(x509, name), WOLFSSL_SUCCESS);
+
+    wolfSSL_X509_sign(x509, priv, EVP_sha256());
+    AssertNotNull((der = wolfSSL_X509_get_der(x509, &derSz)));
+    AssertIntEQ(wolfSSL_CertManagerVerifyBuffer(cm, der, derSz,
+                WOLFSSL_FILETYPE_ASN1), ASN_NAME_INVALID_E);
+    wolfSSL_CertManagerFree(cm);
+    wolfSSL_X509_free(x509);
+    wolfSSL_X509_free(ca);
+
     wolfSSL_EVP_PKEY_free(priv);
 #endif
 }

wolfcrypt/src/asn.c

@@ -7628,6 +7628,25 @@ static int ConfirmNameConstraints(Signer* signer, DecodedCert* cert)
                                                         base->nameSz) == 0) {
                         return 0;
                     }
+                    #ifndef WOLFSSL_NO_ASN_STRICT
+                    /* RFC 5280 section 4.2.1.10
+                       "Restrictions of the form directoryName MUST be
+                        applied to the subject field .... and to any names
+                        of type directoryName in the subjectAltName
+                        extension"
+                    */
+                    if (cert->altDirNames != NULL) {
+                        DNS_entry* cur = cert->altDirNames;
+                        while (cur != NULL) {
+                            if (XMEMCMP(cur->name, base->name, base->nameSz)
+                                    == 0) {
+                                WOLFSSL_MSG("DIR alt name constraint err");
+                                return 0;
+                            }
+                            cur = cur->next;
+                        }
+                    }
+                    #endif /* !WOLFSSL_NO_ASN_STRICT */
                     break;
                 }
             }; /* switch */