MOBOTIX camera detection NSE script

local http = require "http"
local nmap = require "nmap"
local shortport = require "shortport"
local stdnse = require "stdnse"
local string = require "string"

description = [[
Detects HTTP cameras.

Based on HTTP title script.
]]

---
--@output
-- Nmap scan report for scanme.nmap.org (74.207.244.221)
-- PORT   STATE SERVICE
-- 80/tcp open  http
-- |_http-title: Go ahead and ScanMe!
--
-- @xmloutput
-- <elem key="title">Go ahead and ScanMe!</elem>
-- @xmloutput
-- <elem key="title">Wikipedia, the free encyclopedia</elem>
-- <elem key="redirect_url">http://en.wikipedia.org/wiki/Main_Page</elem>

author = "Anonymous hacker"

license = "Same as Nmap--See http://nmap.org/book/man-legal.html"

categories = {"default", "discovery", "safe"}


portrule = shortport.http

action = function(host, port)
  local resp, redirect_url, title

  resp = http.get( host, port, '/' )

  -- check for a redirect
  if resp.location then
    redirect_url = resp.location[#resp.location]
    if resp.status and tostring( resp.status ):match( "30%d" ) then
      resp = http.get( host, port, redirect_url )
    end
  end

  if ( not(resp.body) ) then
    return
  end

  -- try and match mobotix camera keywords
  local match = string.match(resp.body, "[Mm][Oo][Bb][Oo][Tt][Ii][Xx]")

  if match then
    return_val = "MOBOTIX camera detected"
  else
    return
  end


  local output_tab = stdnse.output_table()
  output_tab.title = return_val
  --output_tab.redirect_url = redirect_url

  local output_str = return_val

  return output_tab, output_str
end