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

description = [[
Performs brute force password auditing against the Netbus backdoor ("remote administration") service.
]]

---
-- @usage
-- nmap -p 12345 --script netbus-brute <target>
--
-- @output
-- 12345/tcp open  netbus
-- |_netbus-brute: password123

author = "Toni Ruottu"
license = "Same as Nmap--See http://nmap.org/book/man-legal.html"
categories = {"brute", "intrusive"}


dependencies = {"netbus-version"}

portrule = shortport.port_or_service (12345, "netbus", {"tcp"})

action = function( host, port )
	local try = nmap.new_try()
	local passwords = try(unpwdb.passwords())
	local socket = nmap.new_socket()
	local status, err = socket:connect(host.ip, port.number)
	if not status then
		return
	end
	local buffer, err = stdnse.make_buffer(socket, "\r")
	local _ = buffer() --skip the banner
	for password in passwords do
		local foo = string.format("Password;0;%s\r", password)
		socket:send(foo)
		local login = buffer()
		if login == "Access;1" then
			-- Store the password for other netbus scripts
			local key = string.format("%s:%d", host.ip, port.number)
			if not nmap.registry.netbuspasswords then
				nmap.registry.netbuspasswords = {}
			end
			nmap.registry.netbuspasswords[key] = password
			if password == "" then
				return "<empty>"
			end
			return string.format("%s", password)
		end
	end
	socket:close()
end