id = "Stealth SSH version"

description = "Connects to an SSH server, queries the version string and echos it back. This tends to result\
in the scanning attempt not being logged by the ssh daemon on the target."

author = "Diman Todorov <diman.todorov@gmail.com>"

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

categories = {"demo"}

require "shortport"

portrule = shortport.service("ssh")

action = function(host, port)
	local result, socket

	local catch = function()
		socket:close()
	end

	local try = nmap.new_try(catch)

	result = ""
	socket = nmap.new_socket()

	try(socket:connect(host.ip, port.number))

	result = try(socket:receive_lines(1));
	try(socket:send(result))
	try(socket:close())

	return "" .. string.gsub(result, "\n", "") 
end