github.com/zmap/zlint@v1.1.0/lints/lint_ext_san_not_critical_without_subject.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: 4.2.1.6
    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 extSANNotCritNoSubject struct{}
    36  
    37  func (l *extSANNotCritNoSubject) Initialize() error {
    38  	return nil
    39  }
    40  
    41  func (l *extSANNotCritNoSubject) CheckApplies(c *x509.Certificate) bool {
    42  	return util.IsExtInCert(c, util.SubjectAlternateNameOID)
    43  }
    44  
    45  func (l *extSANNotCritNoSubject) Execute(c *x509.Certificate) *LintResult {
    46  	if e := util.GetExtFromCert(c, util.SubjectAlternateNameOID); !util.NotAllNameFieldsAreEmpty(&c.Subject) && !e.Critical {
    47  		return &LintResult{Status: Error}
    48  	} else {
    49  		return &LintResult{Status: Pass}
    50  	}
    51  }
    52  
    53  func init() {
    54  	RegisterLint(&Lint{
    55  		Name:          "e_ext_san_not_critical_without_subject",
    56  		Description:   "If there is an empty subject field, then the SAN extension MUST be critical",
    57  		Citation:      "RFC 5280: 4.2.1.6",
    58  		Source:        RFC5280,
    59  		EffectiveDate: util.RFC2459Date,
    60  		Lint:          &extSANNotCritNoSubject{},
    61  	})
    62  }