local ipOps = require "ipOps"
local nmap = require "nmap"
local packet = require "packet"
local stdnse = require "stdnse"
local string = require "string"
local table = require "table"
local target = require "target"
-- -*- mode: lua -*-:
-- vim: set filetype=lua :
description = [[
Sniffs the local network for a configurable amount of time (10 seconds
by default) and prints discovered addresses. If the
newtargets
script argument is set, discovered addresses
are added to the scan queue.
Requires root privileges. Either the targets-sniffer.iface
script
argument or -e
Nmap option to define which interface to use.
]]
---
-- @usage
-- nmap -sL --script=targets-sniffer --script-args=newtargets,targets-sniffer.timeout=5s,targets-sniffer.iface=eth0
-- @args targets-sniffer.timeout The amount of time to listen for packets. Default 10s
.
-- @args targets-sniffer.iface The interface to use for sniffing.
-- @args newtargets If true, add discovered targets to the scan queue.
-- @output
-- Pre-scan script results:
-- | targets-sniffer:
-- | 192.168.0.1
-- | 192.168.0.3
-- | 192.168.0.35
-- |_192.168.0.100
-- Thanks to everyone for the feedback and especially Henri Doreau for his detailed feedback and suggestions
author = "Nick Nikolaou"
categories = {"broadcast", "discovery", "safe"}
license = "Same as Nmap--See https://nmap.org/book/man-legal.html"
local interface_info
local all_addresses= {}
local unique_addresses = {}
--Make sure the IP is not a broadcast or the local address
local function check_if_valid(address)
local broadcast = interface_info.broadcast
local local_address = interface_info.address
if address == local_address
or address == broadcast or address == "255.255.255.255"
or address:match('^ff') --IPv6 Multicast addrs
then
return false
else
return true end
end
-- Returns an array of address strings.
local function get_ip_addresses(layer3)
local ip = packet.Packet:new(layer3, layer3:len())
return { ipOps.str_to_ip(ip.ip_bin_src), ipOps.str_to_ip(ip.ip_bin_dst) }
end
prerule = function()
return nmap.is_privileged() and
(stdnse.get_script_args("targets-sniffer.iface") or nmap.get_interface())
end
action = function()
local sock = nmap.new_socket()
local packet_counter = 0
local ip_counter = 0
local timeout = stdnse.parse_timespec(stdnse.get_script_args("targets-sniffer.timeout"))
timeout = (timeout or 10) * 1000
local interface = stdnse.get_script_args("targets-sniffer.iface") or nmap.get_interface()
interface_info = nmap.get_interface_info(interface)
if interface_info==nil then -- Check if we have the interface information
stdnse.debug1("Error: Unable to get interface info. Did you specify the correct interface using 'targets-sniffer.iface=' or '-e '?")
return
end
if sock==nil then
stdnse.debug1("Error - unable to open socket using interface %s",interface)
return
else
sock:pcap_open(interface, 104, true, "ip or ip6")
stdnse.debug1("Will sniff for %s seconds on interface %s.", (timeout/1000),interface)
repeat
local start_time = nmap.clock_ms() -- Used for script timeout
sock:set_timeout(timeout)
local status, _, _, layer3 = sock:pcap_receive()
if status then
local addresses
packet_counter=packet_counter+1
addresses = get_ip_addresses(layer3)
stdnse.debug1("Got IP addresses %s", table.concat(addresses, " "))
for _, addr in ipairs(addresses) do
if check_if_valid(addr) == true then
if not unique_addresses[addr] then
unique_addresses[addr] = true
table.insert(all_addresses, addr)
end
end
end
end
-- Update timeout
timeout = timeout - (nmap.clock_ms() - start_time)
until timeout <= 0
sock:pcap_close()
end
if target.ALLOW_NEW_TARGETS == true then
if nmap.address_family() == 'inet6' then
for _,v in pairs(all_addresses) do
if v:match(':') then
target.add(v)
end
end
else
for _,v in pairs(all_addresses) do
if not v:match(':') then
target.add(v)
end
end
end
else
stdnse.debug1("Not adding targets to newtargets. If you want to do that use the 'newtargets' script argument.")
end
if #all_addresses>0 then
stdnse.debug1("Added %s address(es) to newtargets", #all_addresses)
end
return string.format("Sniffed %s address(es). \n", #all_addresses) .. table.concat(all_addresses, "\n")
end