Class: Gitlab::UntrustedRegexp::RubySyntax

Inherits:
Object
  • Object
show all
Defined in:
lib/gitlab/untrusted_regexp/ruby_syntax.rb

Overview

This class implements support for Ruby syntax of regexps and converts that to RE2 representation: /<regexp>/<flags>

Constant Summary collapse

PATTERN =
%r{^/(?<regexp>.*)/(?<flags>[ismU]*)$}.freeze

Class Method Summary collapse

Class Method Details

.fabricate(pattern, fallback: false) ⇒ Object


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# File 'lib/gitlab/untrusted_regexp/ruby_syntax.rb', line 23

def self.fabricate(pattern, fallback: false)
  self.fabricate!(pattern, fallback: fallback)
rescue RegexpError
  nil
end

.fabricate!(pattern, fallback: false) ⇒ Object

Raises:

  • (RegexpError)

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# File 'lib/gitlab/untrusted_regexp/ruby_syntax.rb', line 29

def self.fabricate!(pattern, fallback: false)
  raise RegexpError, 'Pattern is not string!' unless pattern.is_a?(String)

  matches = pattern.match(PATTERN)
  raise RegexpError, 'Invalid regular expression!' if matches.nil?

  begin
    create_untrusted_regexp(matches[:regexp], matches[:flags])
  rescue RegexpError
    raise unless fallback &&
        Feature.enabled?(:allow_unsafe_ruby_regexp, default_enabled: false)

    create_ruby_regexp(matches[:regexp], matches[:flags])
  end
end

.matches_syntax?(pattern) ⇒ Boolean

Checks if pattern matches a regexp pattern but does not enforce it's validity

Returns:

  • (Boolean)

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# File 'lib/gitlab/untrusted_regexp/ruby_syntax.rb', line 13

def self.matches_syntax?(pattern)
  pattern.is_a?(String) && pattern.match(PATTERN).present?
end

.valid?(pattern, fallback: false) ⇒ Boolean

The regexp can match the pattern `/…/`, but may not be fabricatable: it can be invalid or incomplete: `/match ( string/`

Returns:

  • (Boolean)

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# File 'lib/gitlab/untrusted_regexp/ruby_syntax.rb', line 19

def self.valid?(pattern, fallback: false)
  !!self.fabricate(pattern, fallback: fallback)
end