github.com/zmap/zlint@v1.1.0/lints/lint_ext_cert_policy_explicit_text_not_nfc.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    When the UTF8String encoding is used, all character sequences SHOULD be
    19    normalized according to Unicode normalization form C (NFC) [NFC].
    20  ************************************************/
    21  
    22  import (
    23  	"github.com/zmap/zcrypto/x509"
    24  	"github.com/zmap/zlint/util"
    25  	"golang.org/x/text/unicode/norm"
    26  )
    27  
    28  type ExtCertPolicyExplicitTextNotNFC struct{}
    29  
    30  func (l *ExtCertPolicyExplicitTextNotNFC) Initialize() error {
    31  	return nil
    32  }
    33  
    34  func (l *ExtCertPolicyExplicitTextNotNFC) CheckApplies(c *x509.Certificate) bool {
    35  	for _, text := range c.ExplicitTexts {
    36  		if text != nil {
    37  			return true
    38  		}
    39  	}
    40  	return false
    41  }
    42  
    43  func (l *ExtCertPolicyExplicitTextNotNFC) Execute(c *x509.Certificate) *LintResult {
    44  	for _, firstLvl := range c.ExplicitTexts {
    45  		for _, text := range firstLvl {
    46  			if text.Tag == 12 || text.Tag == 30 {
    47  				if !norm.NFC.IsNormal(text.Bytes) {
    48  					return &LintResult{Status: Warn}
    49  				}
    50  			}
    51  		}
    52  	}
    53  	return &LintResult{Status: Pass}
    54  }
    55  
    56  func init() {
    57  	RegisterLint(&Lint{
    58  		Name:          "w_ext_cert_policy_explicit_text_not_nfc",
    59  		Description:   "When utf8string or bmpstring encoding is used for explicitText field in certificate policy, it SHOULD be normalized by NFC format",
    60  		Citation:      "RFC6181 3",
    61  		Source:        RFC5280,
    62  		EffectiveDate: util.RFC6818Date,
    63  		Lint:          &ExtCertPolicyExplicitTextNotNFC{},
    64  	})
    65  }