metasploit-framework/lib/msf/core/payload/ruby.rb

# -*- coding: binary -*-
require 'msf/core'

module Msf::Payload::Ruby

  def initialize(info = {})
    super(info)

    register_advanced_options(
      [
        # Since space restrictions aren't really a problem, default this to
        # true.
        Msf::OptBool.new('PrependFork', [ false, "Start the payload in its own process via fork or popen", "true" ])
      ]
    )
  end

  def prepends(buf)
    if datastore['PrependFork']
      buf = %Q^
        code = %(#{ Rex::Text.encode_base64(buf) }).unpack(%(m0)).first
        if RUBY_PLATFORM =~ /mswin|mingw|win32/
          inp = IO.popen(%(ruby), %(wb)) rescue nil
          if inp
            inp.write(code)
            inp.close
          end
        else
          if ! Process.fork()
            eval(code) rescue nil
          end
        end
      ^.strip.split(/\n/).map{|line| line.strip}.join("\n")
    end

    buf
  end

end