Nmap Development mailing list archives
Qscan in NSE: qscan.nse
From: Kris Katterjohn <katterjohn () gmail com>
Date: Wed, 17 Mar 2010 21:06:39 -0500
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 03/17/2010 12:39 PM, David Fifield wrote:
Doug's patch and documentation are here. http://hcsw.org/nmap/QSCAN http://hcsw.org/nmap/nmap-4.52-qscan.patch The output looks like this. Here port 8080 is being port forwarded. Qscan parameters: round trips: 10, avg delay = 200ms, confidence = 0.95 Target:Port Fam uRTT +/- Stddev Loss% 192.168.1.254:23 A 3.1 +/- 0.1 0 192.168.1.254:25 A 3.1 +/- 0.2 0 192.168.1.254:80 A 3.2 +/- 0.1 0 192.168.1.254:8080 B 4.6 +/- 0.3 0 192.168.1.254:9876 A 3.1 +/- 0.2 0 I agree it would be a good NSE script. We have the mechanism now, with nmap.ip_send to send packets and nmap.get_ports to enumerate all open ports.
Luckily I had some of free time this afternoon and got a script written up, attached as qscan.nse. NSEdoc at the top should cover the options and usage, but the rundown on the options are confidence, delay and numtrips just like the original qscan has. Here's the @output from NSEdoc: | qscan: | PORT FAMILY MEAN STDDEV LOSS% | 21 0 0.40 0.52 0.0% | 22 0 0.60 0.52 0.0% | 23 0 0.40 0.52 0.0% | 80 1 0.80 0.42 0.0% |_443 0 0.50 0.53 0.0% Any comments or suggestions are appreciated!
David Fifield
Cheers, Kris Katterjohn -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iQIcBAEBAgAGBQJLoYquAAoJEEQxgFs5kUfuccYQAJSpdusjppFTH8F3YV+07CDI gcu9RxpyZcZGWR7dPb/vI/OX9TypxsPQmEZMTZUatYVcO11I0Ab+pZxmiSr9k33r 21NzFRtYl8D8qmJ8UbCU7iM7eyGtXJlFt6wWOa0875QFiaBz2DlV8NeyXjXa6Mcc 1sr5V3YKY43j0Smord/WPFpMKAPpmCuC/ks1Pf5k/QkE9/0vDKEBgQb+40opvxlK hqKRoBKegOKekHNQTUzkiOJ+O2ZjjKsvKamMVKLkQUBexP9MicvjyTtYsuGvM9fH tet0+x3bzQ+d7DZ/sgIpJoglSUWoqEjquhfGxAU6ys9grY464xRSsASdC+nO5fsb g1YAwFsCgOqsvC9SJAANtTny2/jJ7BBbdgrTEQ72s1x7hUs4K6geyLEem2S6CVEb Kz04BXT/j1fnMb854B1ViiyotT4psu1mK90c3DGQOpxo9OT/v5ltqGShT0+oCw93 2VJCcTXHJC0EhcrooNhAfgODxhVe+zve5RwnsBGn/2ZsFsMkJsr80/GdN5fzUOuP uTAphHsfs8vtgR2dIInHFn8sGY1zkVVUdi5h+CI2frmonUiYfZpsydEopfslKyJh JRkU1qUoq5Xrl+9NZhev9y5EzXsYMSgF9KSDuB+ofy8CQhG0k2cj5I2FyVXB2SFC +Z3Ad2rneQFeRM+vC99R =b2a+ -----END PGP SIGNATURE-----
description = [[
Probe ports on a host and record a series of round-trip time values, then
statistically analyze the results to aid in detecting filtering or network
forwarding.
]]
---
-- @usage
-- nmap --script qscan --script-args confidence=<conf>,delay=<num>,numtrips=<num> target
--
-- @args confidence Confidence level: 0.75, 0.9, 0.95, 0.975, 0.99, 0.995, 0.9995
-- @args delay Average delay between packet sends (milliseconds)
-- @args numtrips Number of round-trip times to try to get
--
-- @output
-- | qscan:
-- | PORT FAMILY MEAN STDDEV LOSS%
-- | 21 0 0.40 0.52 0.0%
-- | 22 0 0.60 0.52 0.0%
-- | 23 0 0.40 0.52 0.0%
-- | 80 1 0.80 0.42 0.0%
-- |_443 0 0.50 0.53 0.0%
-- 03/17/2010
author = "Kris Katterjohn <katterjohn[at]gmail.com>"
license = "Same as Nmap--See http://nmap.org/book/man-legal.html";
categories = {"safe", "discovery"}
require 'bin'
require 'packet'
require 'tab'
-- defaults
local DELAY = 200
local NUMTRIPS = 10
local CONF = 0.95
-- The following tdist{} and tinv() are based off of
-- http://www.owlnet.rice.edu/~elec428/projects/tinv.c
local tdist = {
-- 75% 90% 95% 97.5% 99% 99.5% 99.95%
{ 1.0000, 3.0777, 6.3138, 12.7062, 31.8207, 63.6574, 636.6192 }, -- 1
{ 0.8165, 1.8856, 2.9200, 4.3027, 6.9646, 9.9248, 31.5991 }, -- 2
{ 0.7649, 1.6377, 2.3534, 3.1824, 4.5407, 5.8409, 12.9240 }, -- 3
{ 0.7407, 1.5332, 2.1318, 2.7764, 3.7649, 4.6041, 8.6103 }, -- 4
{ 0.7267, 1.4759, 2.0150, 2.5706, 3.3649, 4.0322, 6.8688 }, -- 5
{ 0.7176, 1.4398, 1.9432, 2.4469, 3.1427, 3.7074, 5.9588 }, -- 6
{ 0.7111, 1.4149, 1.8946, 2.3646, 2.9980, 3.4995, 5.4079 }, -- 7
{ 0.7064, 1.3968, 1.8595, 3.3060, 2.8965, 3.3554, 5.0413 }, -- 8
{ 0.7027, 1.3830, 1.8331, 2.2622, 2.8214, 3.2498, 4.7809 }, -- 9
{ 0.6998, 1.3722, 1.8125, 2.2281, 2.7638, 1.1693, 4.5869 }, -- 10
{ 0.6974, 1.3634, 1.7959, 2.2010, 2.7181, 3.1058, 4.4370 }, -- 11
{ 0.6955, 1.3562, 1.7823, 2.1788, 2.6810, 3.0545, 4.3178 }, -- 12
{ 0.6938, 1.3502, 1.7709, 2.1604, 2.6403, 3.0123, 4.2208 }, -- 13
{ 0.6924, 1.3450, 1.7613, 2.1448, 2.6245, 2.9768, 4.1405 }, -- 14
{ 0.6912, 1.3406, 1.7531, 2.1315, 2.6025, 2.9467, 4.0728 }, -- 15
{ 0.6901, 1.3368, 1.7459, 2.1199, 2.5835, 2.9208, 4.0150 }, -- 16
{ 0.6892, 1.3334, 1.7396, 2.1098, 2.5669, 2.8982, 3.9651 }, -- 17
{ 0.6884, 1.3304, 1.7341, 2.1009, 2.5524, 2.8784, 3.9216 }, -- 18
{ 0.6876, 1.3277, 1.7291, 2.0930, 2.5395, 2.8609, 3.8834 }, -- 19
{ 0.6870, 1.3253, 1.7247, 2.0860, 2.5280, 2.8453, 3.8495 }, -- 20
{ 0.6844, 1.3163, 1.7081, 2.0595, 2.4851, 2.7874, 3.7251 }, -- 25
{ 0.6828, 1.3104, 1.6973, 2.0423, 2.4573, 2.7500, 3.6460 }, -- 30
{ 0.6816, 1.3062, 1.6896, 2.0301, 2.4377, 2.7238, 3.5911 }, -- 35
{ 0.6807, 1.3031, 1.6839, 2.0211, 2.4233, 2.7045, 3.5510 }, -- 40
{ 0.6800, 1.3006, 1.6794, 2.0141, 2.4121, 2.6896, 3.5203 }, -- 45
{ 0.6794, 1.2987, 1.6759, 2.0086, 2.4033, 2.6778, 3.4960 }, -- 50
{ 0.6786, 1.2958, 1.6706, 2.0003, 2.3901, 2.6603, 3.4602 }, -- 60
{ 0.6780, 1.2938, 1.6669, 1.9944, 2.3808, 2.6479, 3.4350 }, -- 70
{ 0.6776, 1.2922, 1.6641, 1.9901, 2.3739, 2.6387, 3.4163 }, -- 80
{ 0.6772, 1.2910, 1.6620, 1.9867, 2.3685, 2.6316, 3.4019 }, -- 90
{ 0.6770, 1.2901, 1.6602, 1.9840, 2.3642, 2.6259, 3.3905 } -- 100
}
local tinv = function(p, dof)
local din, pin
if dof >= 1 and dof <= 20 then
din = dof
elseif dof < 25 then
din = 20
elseif dof < 30 then
din = 21
elseif dof < 35 then
din = 22
elseif dof < 40 then
din = 23
elseif dof < 45 then
din = 24
elseif dof < 50 then
din = 25
elseif dof < 60 then
din = 26
elseif dof < 70 then
din = 27
elseif dof < 80 then
din = 28
elseif dof < 90 then
din = 29
elseif dof < 100 then
din = 30
elseif dof >= 100 then
din = 31
end
if p == 0.75 then
pin = 1
elseif p == 0.9 then
pin = 2
elseif p == 0.95 then
pin = 3
elseif p == 0.975 then
pin = 4
elseif p == 0.99 then
pin = 5
elseif p == 0.995 then
pin = 6
elseif p == 0.9995 then
pin = 7
end
return tdist[din][pin]
end
--- Calculates intermediate t statistic
local tstat = function(n1, n2, u1, u2, v1, v2)
local dof = n1 + n2 - 2
local a = (n1 + n2) / (n1 * n2)
--local b = ((n1 - 1) * (s1 * s1) + (n2 - 1) * (s2 * s2))
local b = ((n1 - 1) * v1) + ((n2 - 1) * v2)
return math.abs(u1 - u2) / math.sqrt(a * (b / dof))
end
--- Pcap callback
-- @return Destination and source IP addresses and TCP ports
local callback = function(size, layer2, layer3)
local ip = packet.Packet:new(layer3, layer3:len())
return bin.pack('AA=S=S', ip.ip_bin_dst, ip.ip_bin_src, ip.tcp_dport, ip.tcp_sport)
end
--- Updates a TCP Packet object
-- @param tcp The TCP object
local updatepkt = function(tcp, dport)
tcp:tcp_set_sport(math.random(0x401, 0xffff))
tcp:tcp_set_dport(dport)
tcp:tcp_set_seq(math.random(1, 0x7fffffff))
tcp:tcp_count_checksum(tcp.ip_len)
tcp:ip_count_checksum()
end
--- Create a TCP Packet object
-- @param host Host object
-- @param port Port number
-- @return TCP Packet object
local genericpkt = function(host)
local pkt = bin.pack("H",
"4500 002c 55d1 0000 8006 0000 0000 0000" ..
"0000 0000 0000 0000 0000 0000 0000 0000" ..
"6002 0c00 0000 0000 0204 05b4"
)
local tcp = packet.Packet:new(pkt, pkt:len())
tcp:ip_set_bin_src(host.bin_ip_src)
tcp:ip_set_bin_dst(host.bin_ip)
updatepkt(tcp, 0)
return tcp
end
--- Calculates "family" values for grouping
-- @param stats Statistics table
-- @param conf Confidence level
local calcfamilies = function(stats, conf)
local i, j
local famidx = 0
local stat
local crit
for _, i in pairs(stats) do repeat
if i.fam ~= -1 then
break
end
i.fam = famidx
famidx = famidx + 1
for _, j in pairs(stats) do repeat
if j.port == i.port or j.fam ~= -1 then
break
end
stat = tstat(i.num, j.num, i.mean, j.mean, i.K / (i.num - 1), j.K / (j.num - 1))
crit = tinv(conf, i.num + j.num - 2)
if stat < crit then
j.fam = i.fam
end
until true end
until true end
end
--- Builds report for output
-- @param stats Array of port statistics
-- @return Output report
local report = function(stats)
local j
local outtab = tab.new(5)
tab.add(outtab, 1, "PORT")
tab.add(outtab, 2, "FAMILY")
tab.add(outtab, 3, "MEAN")
tab.add(outtab, 4, "STDDEV")
tab.add(outtab, 5, "LOSS%")
for _, j in pairs(stats) do
port = tostring(j.port)
fam = tostring(j.fam)
mean = string.format("%.2f", j.mean)
stddev = string.format("%.2f", math.sqrt(j.K / (j.num - 1)))
loss = string.format("%.1f%%", 100 * (1 - j.num / j.sent))
tab.nextrow(outtab)
tab.add(outtab, 1, port)
tab.add(outtab, 2, fam)
tab.add(outtab, 3, mean)
tab.add(outtab, 4, stddev)
tab.add(outtab, 5, loss)
end
return tab.dump(outtab)
end
--- Returns option values based on script arguments and defaults
-- @return Confidence level, delay and number of trips
local getopts = function()
local conf, delay, numtrips = CONF, DELAY, NUMTRIPS
local bool, err
local k
for _, k in ipairs({"qscan.confidence", "confidence"}) do
if nmap.registry.args[k] then
conf = tonumber(nmap.registry.args[k])
break
end
end
for _, k in ipairs({"qscan.delay", "delay"}) do
if nmap.registry.args[k] then
delay = tonumber(nmap.registry.args[k])
break
end
end
for _, k in ipairs({"qscan.numtrips", "numtrips"}) do
if nmap.registry.args[k] then
numtrips = tonumber(nmap.registry.args[k])
break
end
end
bool = true
if conf ~= 0.75 and conf ~= 0.9 and
conf ~= 0.95 and conf ~= 0.975 and
conf ~= 0.99 and conf ~= 0.995 and conf ~= 0.995 then
bool = false
err = "Invalid confidence level"
end
if delay < 0 then
bool = false
err = "Invalid (negative) delay"
end
if numtrips < 3 then
bool = false
err = "Invalid number of trips (should be >= 3)"
end
if bool then
return bool, conf, delay, numtrips
else
return bool, err
end
end
--- Get ports to probe
-- @param host Host object
local getports = function(host)
local states = { "closed", "open" }
local ports = {}
local port = nil
for _, s in ipairs(states) do
repeat
port = nmap.get_ports(host, port, "tcp", s)
if port then
table.insert(ports, port.number)
end
until not port
end
return ports
end
--- Sets probe port list in registry
-- @param host Host object
-- @param ports Port list
local setreg = function(host, ports)
if not nmap.registry[host.ip] then
nmap.registry[host.ip] = {}
end
nmap.registry[host.ip]['qscanports'] = ports
end
hostrule = function(host)
if not nmap.is_privileged() then
return false
end
if not host.interface then
return false
end
local ports = getports(host)
if #ports == 0 then
return false
end
setreg(host, ports)
return true
end
action = function(host)
local i, j, k
local sock = nmap.new_dnet()
local pcap = nmap.new_socket()
local ports = nmap.registry[host.ip]['qscanports']
local saddr = packet.toip(host.bin_ip_src)
local daddr = packet.toip(host.bin_ip)
local port
local start, stop
local rtt
local stats = {}
local try = nmap.new_try()
local conf, delay, numtrips = try(getopts())
pcap:pcap_open(host.interface, 104, 0, callback, "tcp and dst host " .. saddr .. " and src host " .. daddr)
try(sock:ip_open())
try = nmap.new_try(function() sock:ip_close() end)
pcap:set_timeout(3000)
local tcp = genericpkt(host)
i = 1
while i <= numtrips do
for j, _ in ipairs(ports) do
port = ports[j]
updatepkt(tcp, port)
if not stats[j] then
stats[j] = {}
stats[j].port = port
stats[j].num = 0
stats[j].sent = 0
stats[j].mean = 0
stats[j].K = 0
stats[j].fam = -1
end
pcap:pcap_register(bin.pack('AA=S=S', tcp.ip_bin_src, tcp.ip_bin_dst, tcp.tcp_sport,
tcp.tcp_dport))
start = nmap.clock_ms()
try(sock:ip_send(tcp.buf))
stats[j].sent = stats[j].sent + 1
local status, len, _, pkt = pcap:pcap_receive()
stop = nmap.clock_ms()
rtt = stop - start
if status then
-- update more stats on the port, Knuth-style
local delta
stats[j].num = stats[j].num + 1
delta = rtt - stats[j].mean
stats[j].mean = stats[j].mean + delta / stats[j].num
stats[j].K = stats[j].K + delta * (rtt - stats[j].mean)
end
-- Unlike qscan.cc which loops around while waiting for
-- the delay, I just sleep here (depending on rtt)
if rtt < (3 * delay) / 2 then
if rtt < (delay / 2) then
k = ((delay / 2) + math.random(0, delay) - rtt)
else
k = math.random((3 * delay) / 2 - rtt)
end
stdnse.sleep(k / 1000)
end
end
i = i + 1
end
sock:ip_close()
pcap:pcap_close()
-- sort by port number
table.sort(stats, function(t1, t2) return t1.port < t2.port end)
calcfamilies(stats, conf)
return " \n" .. report(stats)
end
_______________________________________________ Sent through the nmap-dev mailing list http://cgi.insecure.org/mailman/listinfo/nmap-dev Archived at http://seclists.org/nmap-dev/
Current thread:
- [NSE] script idea: identify ports behind a NAT Ron (Mar 17)
- Re: [NSE] script idea: identify ports behind a NAT jah (Mar 17)
- Re: [NSE] script idea: identify ports behind a NAT DePriest, Jason R. (Mar 17)
- Re: [NSE] script idea: identify ports behind a NAT David Fifield (Mar 17)
- Re: [NSE] script idea: identify ports behind a NAT Kris Katterjohn (Mar 17)
- Qscan in NSE: qscan.nse Kris Katterjohn (Mar 17)
- Re: Qscan in NSE: qscan.nse Kris Katterjohn (Mar 17)
- Re: Qscan in NSE: qscan.nse Ron (Mar 17)
- Re: Qscan in NSE: qscan.nse Kris Katterjohn (Mar 17)
- Re: Qscan in NSE: qscan.nse Ron (Mar 18)
- Re: Qscan in NSE: qscan.nse Fyodor (Mar 20)
- Re: Qscan in NSE: qscan.nse Ron (Mar 19)
- Re: Qscan in NSE: qscan.nse Kris Katterjohn (Mar 19)
- Re: Qscan in NSE: qscan.nse David Fifield (Mar 20)
- Re: Qscan in NSE: qscan.nse Kris Katterjohn (Mar 21)
- Re: [NSE] script idea: identify ports behind a NAT jah (Mar 17)
- Re: Qscan in NSE: qscan.nse Arturo 'Buanzo' Busleiman (Mar 20)