github.com/zmap/zlint@v1.1.0/lints/lint_dnsname_contains_empty_label.go (about)

     1  package lints
     2  
     3  /*
     4   * ZLint Copyright 2018 Regents of the University of Michigan
     5   *
     6   * Licensed under the Apache License, Version 2.0 (the "License"); you may not
     7   * use this file except in compliance with the License. You may obtain a copy
     8   * of the License at http://www.apache.org/licenses/LICENSE-2.0
     9   *
    10   * Unless required by applicable law or agreed to in writing, software
    11   * distributed under the License is distributed on an "AS IS" BASIS,
    12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
    13   * implied. See the License for the specific language governing
    14   * permissions and limitations under the License.
    15   */
    16  
    17  import (
    18  	"strings"
    19  
    20  	"github.com/zmap/zcrypto/x509"
    21  	"github.com/zmap/zlint/util"
    22  )
    23  
    24  type DNSNameEmptyLabel struct{}
    25  
    26  func (l *DNSNameEmptyLabel) Initialize() error {
    27  	return nil
    28  }
    29  
    30  func (l *DNSNameEmptyLabel) CheckApplies(c *x509.Certificate) bool {
    31  	return util.IsSubscriberCert(c) && util.DNSNamesExist(c)
    32  }
    33  
    34  func domainHasEmptyLabel(domain string) bool {
    35  	labels := strings.Split(domain, ".")
    36  	for _, elem := range labels {
    37  		if elem == "" {
    38  			return true
    39  		}
    40  	}
    41  	return false
    42  }
    43  
    44  func (l *DNSNameEmptyLabel) Execute(c *x509.Certificate) *LintResult {
    45  	if c.Subject.CommonName != "" && !util.CommonNameIsIP(c) {
    46  		if domainHasEmptyLabel(c.Subject.CommonName) {
    47  			return &LintResult{Status: Error}
    48  		}
    49  	}
    50  	for _, dns := range c.DNSNames {
    51  		if domainHasEmptyLabel(dns) {
    52  			return &LintResult{Status: Error}
    53  		}
    54  	}
    55  	return &LintResult{Status: Pass}
    56  }
    57  
    58  func init() {
    59  	RegisterLint(&Lint{
    60  		Name:          "e_dnsname_empty_label",
    61  		Description:   "DNSNames should not have an empty label.",
    62  		Citation:      "BRs: 7.1.4.2",
    63  		Source:        CABFBaselineRequirements,
    64  		EffectiveDate: util.CABEffectiveDate,
    65  		Lint:          &DNSNameEmptyLabel{},
    66  	})
    67  }