# Author: Carlos Perez at carlos_perez[at]darkoperator.com
#-------------------------------------------------------------------------------
################## Variable Declarations ##################
@client = client
@@exec_opts = Rex::Parser::Arguments.new(
  "-h" => [ false, "Help menu." ],
  "-i" => [ false, "Enumerate Local Interfaces"],
  "-r" => [ true,  "The target address range or CIDR identifier"],
  "-s" => [ false,  "Save found IP Addresses to logs."]
)



def enum_int
  print_status("Enumerating Interfaces")
  client.net.config.interfaces.each do |i|
    if not i.mac_name =~ /Loopback/
      print_status("\t#{i.mac_name}")
      print_status("\t#{i.ip}")
      print_status("\t#{i.netmask}")
      print_status()
    end

  end
end

def arp_scan(cidr)
  print_status("ARP Scanning #{cidr}")
  ws = client.railgun.ws2_32
  iphlp = client.railgun.iphlpapi
  i, a = 0, []
  iplst,found = [],""
  ipadd = Rex::Socket::RangeWalker.new(cidr)
  numip = ipadd.num_ips
  while (iplst.length < numip)
    ipa = ipadd.next_ip
    if (not ipa)
      break
    end
    iplst << ipa
  end
  iplst.each do |ip_text|
    if i < 10
      a.push(::Thread.new {
          h = ws.inet_addr(ip_text)
          ip = h["return"]
          h = iphlp.SendARP(ip,0,6,6)
          if h["return"] == client.railgun.const("NO_ERROR")
            mac_text = h["pMacAddr"].unpack('C*').map { |e| "%02x" % e }.join(':')
            print_status("IP: #{ip_text} MAC #{mac_text}")
            found << "#{ip_text}\n"
          end
        })
      i += 1
    else
      sleep(0.05) and a.delete_if {|x| not x.alive?} while not a.empty?
      i = 0
    end
  end
  a.delete_if {|x| not x.alive?} while not a.empty?
  return found
end

def save_found(found_ip)
  info = @client.sys.config.sysinfo
  # Create Filename info to be appended to downloaded files
  filenameinfo = "_" + ::Time.now.strftime("%Y%m%d.%M%S")

  # Create a directory for the logs
  logs = ::File.join(Msf::Config.log_directory,'scripts', 'arp_scanner',Rex::FileUtils.clean_path(info['Computer'] + filenameinfo))
  # Create the log directory
  ::FileUtils.mkdir_p(logs)

  #log file name
  dest = Rex::FileUtils.clean_path(logs + "/" + info['Computer'] + filenameinfo + ".txt")

  print_status("Saving found IP's to #{dest}")
  file_local_write(dest,found_ip)

end
save2log = false
cidr2scan = ""
@@exec_opts.parse(args) { |opt, idx, val|
  case opt
  when "-h"
    print_line "Meterpreter Script for performing an ARPS Scan Discovery."
    print_line(@@exec_opts.usage)
    raise Rex::Script::Completed
  when "-i"
    enum_int
    raise Rex::Script::Completed
  when "-r"
    cidr2scan = val
  when "-s"
    save2log = true
  end
}
if client.platform =~ /win32|win64/
  if args.length > 0
    if save2log
      save_found(arp_scan(cidr2scan))
    else
      arp_scan(cidr2scan)
    end
  else
    print_line "Meterpreter Script for performing an ARPS Scan Discovery."
    print_line(@@exec_opts.usage)
    raise Rex::Script::Completed
  end
else
  print_error("This version of Meterpreter is not supported with this Script!")
  raise Rex::Script::Completed
end