module Ronin::Support::Encoding::Ruby

Contains methods for encoding/decoding escaping/unescaping Ruby strings.

## Core-Ext Methods

@api public

Constants

UNESCAPE_CHARS

Common escaped characters.

Public Class Methods

decode(data) click to toggle source

Decodes the Ruby encoded data.

@param [String] data

The given Ruby data to decode.

@return [String]

The decoded data.

@see unescape

# File lib/ronin/support/encoding/ruby.rb, line 130
def self.decode(data)
  unescape(data)
end
encode(data) click to toggle source

Encodes each byte of the given data as a Ruby escaped character.

@param [String] data

The given data to encode.

@return [String]

The encoded Ruby String.

@example

Encoding::Ruby.encode("hello")
# => "\\x68\\x65\\x6c\\x6c\\x6f"
# File lib/ronin/support/encoding/ruby.rb, line 103
def self.encode(data)
  encoded = String.new

  if data.valid_encoding?
    data.each_codepoint do |codepoint|
      encoded << encode_byte(codepoint)
    end
  else
    data.each_byte do |byte|
      encoded << encode_byte(byte)
    end
  end

  return encoded
end
encode_byte(byte) click to toggle source

Encodes a byte as a Ruby escaped character.

@param [Integer] byte

The byte value to encode.

@return [String]

The escaped Ruby character.

@example

Encoding::Ruby.encode_byte(0x41)
# => "\\x41"
Encoding::Ruby.encode_byte(0x100)
# => "\\u100"
Encoding::Ruby.encode_byte(0x10000)
# => "\\u{10000}"
# File lib/ronin/support/encoding/ruby.rb, line 56
def self.encode_byte(byte)
  if byte >= 0x00 && byte <= 0xff
    "\\x%.2X" % byte
  elsif byte >= 0x100 && byte <= 0xffff
    "\\u%.4X" % byte
  elsif byte >= 0x10000 && byte <= 0x10ffff
    "\\u{%.X}" % byte
  else
    raise(RangeError,"#{byte.inspect} out of char range")
  end
end
escape(data) click to toggle source

Escapes the Ruby string.

@param [String] data

The data to escape.

@return [String]

The Ruby escaped String.
# File lib/ronin/support/encoding/ruby.rb, line 143
def self.escape(data)
  data.dump[1..-2]
end
escape_byte(byte) click to toggle source

Escapes a byte as a Ruby character.

@param [Integer] byte

The byte value to escape.

@return [String]

The escaped Ruby character.

@raise [RangeError]

The byte value isn't a valid ASCII or UTF byte.
# File lib/ronin/support/encoding/ruby.rb, line 80
def self.escape_byte(byte)
  char = if byte >= 0x00 && byte <= 0xff
           byte.chr
         else
           byte.chr(Encoding::UTF_8)
         end

  return char.dump[1..-2]
end
quote(data) click to toggle source

Escapes and quotes the given data as a Ruby string.

@param [String] data

The given data to escape and quote.

@return [String]

The quoted Ruby string.

@example

Encoding::Ruby.quote("hello\nworld\n")
# => "\"hello\\nworld\\n\""
# File lib/ronin/support/encoding/ruby.rb, line 210
def self.quote(data)
  data.dump
end
unescape(data) click to toggle source

Unescapes the escaped String.

@param [String] data

The given Ruby escaped data.

@return [String]

The unescaped version of the hex escaped String.

@example

Encoding::Ruby.unescape("\\x68\\x65\\x6c\\x6c\\x6f")
# => "hello"
# File lib/ronin/support/encoding/ruby.rb, line 176
def self.unescape(data)
  unescaped = String.new(encoding: Encoding::UTF_8)
  scanner   = StringScanner.new(data)

  until scanner.eos?
    unescaped << if (unicode_escape = scanner.scan(/\\(?:[0-7]{1,3}|[0-7])/))
                   unicode_escape[1,3].to_i(8).chr
                 elsif (hex_escape = scanner.scan(/\\u[0-9a-fA-F]{4,8}/))
                   hex_escape[2..].to_i(16).chr(Encoding::UTF_8)
                 elsif (hex_escape = scanner.scan(/\\x[0-9a-fA-F]{1,2}/))
                   hex_escape[2..].to_i(16).chr
                 elsif (escape     = scanner.scan(/\\./))
                   UNESCAPE_CHARS[escape]
                 else
                   scanner.getch
                 end
  end

  return unescaped
end
unquote(data) click to toggle source

Removes the quotes an unescapes a quoted string.

@param [String] data

The given Ruby string.

@return [String]

The un-quoted String if the String begins and ends with quotes, or
the same String if it is not quoted.

@example

Encoding::Ruby.unquote("\"hello\\nworld\"")
# => "hello\nworld"
Encoding::Ruby.unquote("'hello\\'world'")
# => "hello'world"
# File lib/ronin/support/encoding/ruby.rb, line 230
def self.unquote(data)
  if (data[0] == '"' && data[-1] == '"')
    unescape(data[1..-2])
  elsif (data[0] == "'" && data[-1] == "'")
    data[1..-2].gsub(/\\(['\\])/,'\1')
  else
    data
  end
end