Class: Obfuscate::Crypt

Inherits:
Object
  • Object
show all
Defined in:
lib/obfuscate/crypt.rb

Constant Summary collapse

Base64Error = 
Class.new(StandardError)
UnsupportedModeError = 
Class.new(StandardError)

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(config) ⇒ Crypt

New instance of Obfuscate::Crypt



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# File 'lib/obfuscate/crypt.rb', line 30

def initialize(config)
  @crypt = Crypt::Blowfish.new( config.salt )
  @config = config
end

Instance Attribute Details

#config ⇒ Object (readonly)

Returns the value of attribute config.



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# File 'lib/obfuscate/crypt.rb', line 24

def config
  @config
end

#exec_config ⇒ Object (readonly)

Returns the value of attribute exec_config.



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# File 'lib/obfuscate/crypt.rb', line 25

def exec_config
  @exec_config
end

Instance Method Details

#clarify(text, override_mode = nil) ⇒ String

Clarify text



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# File 'lib/obfuscate/crypt.rb', line 64

def clarify(text, override_mode = nil)

  @exec_config = @config.apply(:mode => (override_mode || @config.mode))
  obfuscated = text.to_s

  if @exec_config.encode
    obfuscated << "=" if @exec_config.remove_trailing_equal?
    obfuscated = Base64.urlsafe_decode64(obfuscated)
  end

  begin
    if @exec_config.mode == :string
      @crypt.decrypt_string(obfuscated)
    elsif @exec_config.mode == :block
      @crypt.decrypt_block(obfuscated).strip
    else
      raise UnsupportedModeError.new("Unknown mode: #{@exec_config.mode}")
    end
  rescue ArgumentError => ex
    raise Base64Error.new("Cannot decode #{text}") if ex.message == 'invalid base64'

    raise ex
  rescue => ex
    raise Base64Error.new("Cannot decode #{text}") if ex.message == "undefined method `%'"

    raise ex
  end
end

#obfuscate(text, override_mode = nil) ⇒ String

Obfuscate text



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# File 'lib/obfuscate/crypt.rb', line 39

def obfuscate(text, override_mode = nil)

  @exec_config = @config.apply(:mode => (override_mode || @config.mode) )

  obfuscated = nil
  if @exec_config.mode == :string
    obfuscated = @crypt.encrypt_string(text)
  elsif @exec_config.mode == :block
    obfuscated = @crypt.encrypt_block(text.to_s.ljust(8))
  else
    raise "Unsupport Mode"
  end

  if @exec_config.encode
    obfuscated = Base64.urlsafe_encode64(obfuscated).strip
    obfuscated = obfuscated.chomp("=") if @exec_config.remove_trailing_equal?
  end

  obfuscated
end