local comm = require "comm" local nmap = require "nmap" local stdnse = require "stdnse" local string = require "string" local table = require "table" description = [[ Extracts information from Quake game servers and other game servers which use the same protocol. Quake uses UDP packets, which because of source spoofing can be used to amplify a denial-of-service attack. For each request, the script reports the payload amplification as a ratio. The format used is response_bytes/request_bytes=ratio http://www.gamers.org/dEngine/quake/QDP/qnp.html ]] --- -- @usage -- nmap -n -sU -Pn --script quake1-info -pU:26000-26004 -- -- -- @output -- PORT STATE SERVICE -- 26000/udp open quake -- | quake1-info: -- | server info exchange payload amplification: 59/12=4.916667 -- | listen address: 10.200.200.10:26000 -- | server name: An anonymous Debian server -- | level name: dm1 -- | players: 1/8 -- | player table -- | player 1: fragmeister -- | player info exchange payload amplification: 49/6=8.166667 -- | client address: 192.168.0.10:40430 -- | connect time: 55587 secs -- | frags: -1 -- | shirt: green3 -- | pants: orange6 -- |_ protocol version: released (0x3) -- -- @xmloutput -- 59/12=4.916667 -- 10.200.200.10:26000 -- An anonymous Debian server -- dm1 -- 1/8 -- --
-- 49/6=8.166667 -- fragmeister -- 192.168.0.10:40430 -- 55587 secs -- -1 -- green3 -- orange6 --
-- -- released (0x3) categories = {"default", "discovery", "safe", "version"} author = "Ulrik Haugen" copyright = "Linköpings universitet 2014, Ulrik Haugen 2014" license = "Same as Nmap--See https://nmap.org/book/man-legal.html" --- Proceed with action on open/open|filtered udp ports in interval -- [26000, 26004] and whatever Quake is listed under in nmap-services. function portrule(host, port) return (port.state == 'open' or port.state == 'open|filtered') and port.protocol == 'udp' and ((26000 <= port.number and port.number <= 26004) or port.service == 'quake') and nmap.version_intensity() >= 7 end --- Like assert but put /message/ in the ERROR key in /results_table/ to -- better suit collate_results and pass 0 as level to error to ensure -- the error message will not be prefixed with file and line number. -- /results_table/ may be left out. local function assert_w_table(condition, message, results_table) if condition then return condition else results_table = results_table or {} results_table.ERROR = message error(results_table, 0) end end -- Protocol constants and tables. local ctrl_pkt_type = 0x8000 local ccreq_server_info = 0x02 local ccrep_server_info = 0x83 local ccreq_player_info = 0x03 local ccrep_player_info = 0x84 local game_name = "QUAKE" local net_protocol_versions = { [ 0x01 ] = "qtest1", [ 0x02 ] = "unknown", [ 0x03 ] = "released" } local net_protocol_released = 0x03 local color_codes = { [ 0x0 ] = "gray0", [ 0x1 ] = "brown1", [ 0x2 ] = "lavender2", [ 0x3 ] = "green3", [ 0x4 ] = "red4", [ 0x5 ] = "light green5", [ 0x6 ] = "orange6", [ 0x7 ] = "light brown7", [ 0x8 ] = "violet8", [ 0x9 ] = "pink9", [ 0xa ] = "beige10", [ 0xb ] = "green11", [ 0xc ] = "yellow12", [ 0xd ] = "blue13" } --- Request player info from /host/:/port/ for player /id/, return -- player info as a table on success and raise an error on failure. local function get_player_info(host, port, id) local player_info = stdnse.output_table() local req_pl = string.pack('>I2 I2 BB', ctrl_pkt_type, -- packet type 2+2+1+1, -- packet length ccreq_player_info, -- operation code id - 1) -- player number (0 indexed) -- iptables -m u32 --u32 '0x1c=0x80000006&&0x1d&0xff=0x03' local status, rep_pl = comm.exchange(host, port, req_pl) assert_w_table(status, "No response to request for player info") assert_w_table(#rep_pl >= 4, "Response too small for packet header") player_info.player_ratio = string.format("%d/%d=%f", rep_pl:len(), req_pl:len(), rep_pl:len()/req_pl:len() ) local rep_pkt_type, rep_pl_len, pos = string.unpack('>I2 I2', rep_pl) assert_w_table(rep_pl_len == rep_pl:len(), string.format("Incorrect reply packet length: %d" .. " received, %d bytes in packet", rep_pl_len, rep_pl:len()), player_info) local term_pos = rep_pl_len + 1 assert_w_table(rep_pkt_type == ctrl_pkt_type, "Bad reply packet type", player_info) -- frags and connect_time are sent little endian: local rep_opc, player_id, name, colors, frags, connect_time, client_address, pos = string.unpack('>BBzBxxxz', rep_pl, pos) assert_w_table(pos == term_pos, "Error parsing reply (packet type/ length)", player_info) assert_w_table(rep_opc == ccrep_player_info, string.format("Incorrect operation code 0x%x in reply," .. " should be 0x%x", rep_opc, ccrep_player_info), player_info) player_info.name = name player_info.client_address = client_address player_info.connect_time = string.format("%d secs", connect_time) player_info.frags = frags player_info.shirt = color_codes[colors >> 4] or "INVALID" player_info.pants = color_codes[colors & 0x0f] or "INVALID" return player_info end --- Request player info from /host/:/port/ for players [1, -- /cur_players/], return player infos or errors in a table. local function get_player_table(host, port, cur_players) local player_table = stdnse.output_table() for id = 1, cur_players do -- At this point we have established that the target is a Quake -- game server so lost ccreq or ccrep player info packets are -- merely noted in the output, they don't abort the script. local status, player_info = pcall(get_player_info, host, port, id) player_table[string.format("player %d", id)] = player_info end return player_table end --- Request server info and possibly player infos from /host/:/port/, -- return server info and any player infos as a table on success and -- raise an error on failure. local function get_server_info(host, port) local server_info = stdnse.output_table() local req_pl = string.pack('>I2I2BzB', ctrl_pkt_type, -- packet type 2+2+1+game_name:len()+1+1, -- packet length ccreq_server_info, -- operation code game_name, net_protocol_released) -- net protocol version -- iptables -m u32 --u32 '0x1c=0x8000000c&&0x20=0x02515541&&0x24=0x4b450003' local status, rep_pl = comm.exchange(host, port, req_pl) assert_w_table(status, "No response to request for server info") assert_w_table(#rep_pl >= 4, "Response too small for packet header") nmap.set_port_state(host, port, 'open') server_info.server_ratio = string.format("%d/%d=%f", rep_pl:len(), req_pl:len(), rep_pl:len()/req_pl:len()) local rep_pkt_type, rep_pl_len, pos = string.unpack('>I2 I2', rep_pl) assert_w_table(rep_pkt_type == ctrl_pkt_type, string.format("Bad reply packet type 0x%x, expected 0x%x", rep_pkt_type, ctrl_pkt_type), server_info) assert_w_table(rep_pl_len == rep_pl:len(), string.format("Bad reply packet length: %d received," .. " %d bytes in packet", rep_pl_len, rep_pl:len()), server_info) local term_pos = rep_pl_len + 1 local rep_opc, pos = string.unpack('>B', rep_pl, pos) assert_w_table(rep_opc == ccrep_server_info, string.format("Bad operation code 0x%x in reply," .. " expected 0x%x", rep_opc, ccrep_server_info), server_info) local server_address, server_host_name, level_name, cur_players, max_players, net_protocol_version, pos = string.unpack('>zzzBBB', rep_pl, pos) assert_w_table(pos == term_pos, "Error parsing reply (packet type/length)", server_info) port.version.name = "quake" port.version.product = "Quake 1 server" port.version.version = net_protocol_versions[net_protocol_version] nmap.set_port_version(host, port) local player_table = get_player_table(host, port, cur_players) server_info.listen_address = server_address server_info.server_name = server_host_name server_info.level_name = level_name server_info.players = string.format("%d/%d", cur_players, max_players) server_info.player_table = player_table server_info.protocol_version = string.format( "%s (0x%x)", net_protocol_versions[net_protocol_version], net_protocol_version) return server_info end --- Return a function from structured to unstructured output indenting -- nested tables /offset/ or two spaces with special treatment of name -- keys and optionally using /xlate_key/ to format keys. local function make_formatter(offset, xlate_key) offset = offset or 2 xlate_key = xlate_key or function(key) return key:gsub("_", " ") end --- Format /results_table/ as a string starting /indent/ or zero -- steps from the margin for the name key and adding offset steps -- for other table contents and again for the contents of nested -- tables. local function formatter(results_table, indent) indent = indent or 0 local output = {} if results_table.name then table.insert(output, string.format("%s%s", ({ [ false ] = ": ", [ true ] = "\n" })[indent == 0], results_table.name)) end for key, value in pairs(results_table) do -- name is printed already if key ~= 'name' then if type(value) == 'table' then table.insert(output, string.format("\n%s%s", string.rep(" ", indent + offset), xlate_key(key))) table.insert(output, formatter(value, indent + offset)) else table.insert(output, string.format("\n%s%s: %s", string.rep(" ", indent + offset), xlate_key(key), value)) end end end return table.concat(output, '') end return formatter end --- Use /formatter/ to produce unstructured output from -- /results_table/ considering /status/. Return structured and -- unstructured output. local function collate_results(formatter, status, results_table) if not status and nmap.debugging() < 1 then return nil end return results_table, formatter(results_table) end --- Nmap entry point. function action(host, port) local xlate_table = { player_ratio = "player info exchange payload amplification", server_ratio = "server info exchange payload amplification", } local function xlate_key(key) return xlate_table[key] or key:gsub("_", " ") end return collate_results(make_formatter(nil, xlate_key), pcall(get_server_info, host, port)) end