github.com/zmap/zlint@v1.1.0/lints/lint_subject_empty_without_san.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  /*************************************************************************
    18  RFC 5280: 4.2 & 4.2.1.6
    19  Further, if the only subject identity included in the certificate is
    20  an alternative name form (e.g., an electronic mail address), then the
    21  subject distinguished name MUST be empty (an empty sequence), and the
    22  subjectAltName extension MUST be present.  If the subject field
    23  contains an empty sequence, then the issuing CA MUST include a
    24  subjectAltName extension that is marked as critical.  When including
    25  the subjectAltName extension in a certificate that has a non-empty
    26  subject distinguished name, conforming CAs SHOULD mark the
    27  subjectAltName extension as non-critical.
    28  *************************************************************************/
    29  
    30  import (
    31  	"github.com/zmap/zcrypto/x509"
    32  	"github.com/zmap/zlint/util"
    33  )
    34  
    35  type emptyWithoutSAN struct{}
    36  
    37  func (l *emptyWithoutSAN) Initialize() error {
    38  	return nil
    39  }
    40  
    41  func (l *emptyWithoutSAN) CheckApplies(cert *x509.Certificate) bool {
    42  	return true
    43  }
    44  
    45  func (l *emptyWithoutSAN) Execute(cert *x509.Certificate) *LintResult {
    46  	if subjectIsEmpty(cert) && !util.IsExtInCert(cert, util.SubjectAlternateNameOID) {
    47  		return &LintResult{Status: Error}
    48  	} else {
    49  		return &LintResult{Status: Pass}
    50  	}
    51  }
    52  
    53  func subjectIsEmpty(cert *x509.Certificate) bool {
    54  	if cert.Subject.Names == nil {
    55  		return true
    56  	}
    57  	return false
    58  }
    59  
    60  func init() {
    61  	RegisterLint(&Lint{
    62  		Name:          "e_subject_empty_without_san",
    63  		Description:   "CAs MUST support subject alternative name if the subject field is an empty sequence",
    64  		Citation:      "RFC 5280: 4.2 & 4.2.1.6",
    65  		Source:        RFC5280,
    66  		EffectiveDate: util.RFC2459Date,
    67  		Lint:          &emptyWithoutSAN{},
    68  	})
    69  }