| Path : /usr/share/nmap/scripts/ |
|
|
| Current File : //usr/share/nmap/scripts/broadcast-igmp-discovery.nse |
local nmap = require "nmap"
local stdnse = require "stdnse"
local table = require "table"
local bin = require "bin"
local packet = require "packet"
local ipOps = require "ipOps"
local target = require "target"
local coroutine = require "coroutine"
local string = require "string"
local io = require "io"
description = [[
Discovers targets that have IGMP Multicast memberships and grabs interesting information.
The scripts works by sending IGMP Membership Query message to the 224.0.0.1 All
Hosts multicast address and listening for IGMP Membership Report messages. The
script then extracts all the interesting information from the report messages
such as the version, group, mode, source addresses (depending on the version).
The script defaults to sending an IGMPv2 Query but this could be changed to
another version (version 1 or 3) or to sending queries of all three version. If
no interface was specified as a script argument or with the -e option, the
script will proceed to sending queries through all the valid ethernet
interfaces.
]]
---
-- @args broadcast-igmp-discovery.timeout Time to wait for reports in seconds.
-- Defaults to <code>5</code> seconds.
--
-- @args broadcast-igmp-discovery.version IGMP version to use. Could be
-- <code>1</code>, <code>2</code>, <code>3</code> or <code>all</code>. Defaults to <code>2</code>
--
-- @args broadcast-igmp-discovery.interface Network interface to use.
--
-- @args broadcast-igmp-discovery.mgroupnamesdb Database with multicast group names
--
--@usage
-- nmap --script broadcast-igmp-discovery
-- nmap --script broadcast-igmp-discovery -e wlan0
-- nmap --script broadcast-igmp-discovery
-- --script-args 'broadcast-igmp-discovery.version=all, broadcast-igmp-discovery.timeout=3'
--
--@output
--Pre-scan script results:
-- | broadcast-igmp-discovery:
-- | 192.168.2.2
-- | Interface: tap0
-- | Version: 3
-- | Group: 239.1.1.1
-- | Mode: EXCLUDE
-- | Description: Organization-Local Scope (rfc2365)
-- | Group: 239.1.1.2
-- | Mode: EXCLUDE
-- | Description: Organization-Local Scope (rfc2365)
-- | Group: 239.1.1.44
-- | Mode: INCLUDE
-- | Description: Organization-Local Scope (rfc2365)
-- | Sources:
-- | 192.168.31.1
-- | 192.168.1.3
-- | Interface: wlan0
-- | Version: 2
-- | Group: 239.255.255.250
-- | Description: Organization-Local Scope (rfc2365)
-- | 192.168.1.3
-- | Interface: wlan0
-- | Version: 2
-- | Group: 239.255.255.253
-- | Description: Organization-Local Scope (rfc2365)
-- |_ Use the newtargets script-arg to add the results as targets
--
--
-- The Multicast Group names DB can be created by the following script:
--
-- #!/usr/bin/awk -f
-- BEGIN { FS="<|>"; }
-- /<record/ { r=1; addr1=""; addr2=""; rfc=""; }
-- /<addr>.*-.*<\/addr>/ { T=$3; FS="-"; $0=T; addr1=$1; addr2=$2; FS="<|>"; }
-- /<addr>[^-]*<\/addr>/ { addr1=$3; addr2=$3; }
-- /<description>/ { desc=$3; }
-- /<xref type=\"rfc\"/ { T=$2; FS="\""; $0=T; rfc=" (" $4 ")"; FS="<|>"; }
-- /<\/record/ { r=0; if (addr1) { print addr1 "\t" addr2 "\t" desc rfc; } }
--
-- wget -O- http://www.iana.org/assignments/multicast-addresses/multicast-addresses.xml | \
-- ./extract-mg-names >nselib/data/mgroupnames.db
prerule = function()
if nmap.address_family() ~= 'inet' then
stdnse.print_verbose("%s is IPv4 only.", SCRIPT_NAME)
return false
end
if ( not(nmap.is_privileged()) ) then
stdnse.print_verbose("%s not running due to lack of privileges.", SCRIPT_NAME)
return false
end
return true
end
author = "Hani Benhabiles"
license = "Same as Nmap--See http://nmap.org/book/man-legal.html"
categories = {"discovery", "safe", "broadcast"}
--- Parses a raw igmp packet and return a structred packet.
-- @param data string IGMP Raw packet.
-- @return response table Structured igmp packet.
local igmpParse = function(data)
local index
local response = {}
local group, source
-- Report type (0x12 == v1, 0x16 == v2, 0x22 == v3)
index, response.type = bin.unpack(">C", data, index)
if response.type == 0x12 or response.type == 0x16 then
-- Max response time
index, response.maxrt = bin.unpack(">C", data, index)
-- Checksum
index, response.checksum = bin.unpack(">S", data, index)
-- Multicast group
index, response.group = bin.unpack("<I", data, index)
response.group = ipOps.fromdword(response.group)
return response
elseif response.type == 0x22 and #data >= 12 then
-- Skip reserved byte
index = index + 1
-- Checksum
index, response.checksum = bin.unpack(">S", data, index)
-- Skip reserved byte
index = index + 2
-- Number of groups
index, response.ngroups = bin.unpack(">S", data, index)
response.groups = {}
for i=1,response.ngroups do
group = {}
-- Mode is either INCLUDE or EXCLUDE
index, group.mode = bin.unpack(">C", data, index)
-- Auxiliary data length in the group record (in 32bits units)
index, group.auxdlen = bin.unpack(">C", data, index)
-- Number of source addresses
index, group.nsrc = bin.unpack(">S", data, index)
index, group.address = bin.unpack("<I", data, index)
group.address = ipOps.fromdword(group.address)
group.src = {}
if group.nsrc > 0 then
for i=1,group.nsrc do
index, source = bin.unpack("<I", data, index)
table.insert(group.src, ipOps.fromdword(source))
end
end
-- Skip auxiliary data
index = index + group.auxdlen
-- Insert group
table.insert(response.groups, group)
end
return response
end
end
--- Listens for IGMP Membership reports packets.
-- @param interface Interface to listen on.
-- @param timeout Amount of time to listen for.
-- @param responses table to put valid responses into.
local igmpListener = function(interface, timeout, responses)
local condvar = nmap.condvar(responses)
local start = nmap.clock_ms()
local listener = nmap.new_socket()
local p, igmp_raw, status, l3data, response, _
local devices = {}
listener:set_timeout(100)
listener:pcap_open(interface.device, 1024, true, 'ip proto 2')
while (nmap.clock_ms() - start) < timeout do
status, _, _, l3data = listener:pcap_receive()
if status then
p = packet.Packet:new(l3data, #l3data)
igmp_raw = string.sub(l3data, p.ip_hl*4 + 1)
if p then
-- check the first byte before sending to the parser
-- response 0x12 == Membership Response version 1
-- response 0x16 == Membership Response version 2
-- response 0x22 == Membership Response version 3
local igmptype = igmp_raw:byte(1)
if igmptype == 0x12 or igmptype == 0x16 or igmptype == 0x22 then
response = igmpParse(igmp_raw)
if response then
response.src = p.ip_src
response.interface = interface.shortname
-- Many hosts return more than one same response message
-- this is to not output duplicates
if not devices[response.src..response.type..(response.group or response.ngroups)] then
devices[response.src..response.type..(response.group or response.ngroups)] = true
table.insert(responses, response)
end
end
end
end
end
end
condvar("signal")
end
--- Crafts a raw IGMP packet.
-- @param interface Source interface of the packet.
-- @param vesion IGMP version. Could be 1, 2 or 3.
-- @return string Raw IGMP packet.
local igmpRaw = function(interface, version)
-- Only 1, 2 and 3 are valid IGMP versions
if version ~= 1 and version ~= 2 and version ~= 3 then
stdnse.print_debug("IGMP version %s doesn't exist.", version)
return
end
-- Let's craft an IGMP Membership Query
local igmp_raw = bin.pack(">C", 0x11) -- Membership Query, same for all versions
if version == 1 then
igmp_raw = igmp_raw .. bin.pack(">C", 0x00) -- Unused, 0x00 for version 1 only
else
igmp_raw = igmp_raw .. bin.pack(">C", 0x16) -- Max response time: 10 Seconds, for version 2 and 3
end
igmp_raw = igmp_raw .. bin.pack(">S", 0x00) -- Checksum, calculated later
igmp_raw = igmp_raw .. bin.pack(">I", 0x00) -- Multicast Address: 0.0.0.0
if version == 3 then
-- Reserved = 4 bits (Should be zeroed)
-- Supress Flag = 1 bit
-- QRV (Querier's Robustness Variable) = 3 bits
-- all are set to 0
igmp_raw = igmp_raw .. bin.pack(">C", 0x00)
-- QQIC (Querier's Query Interval Code) in seconds = Set to 0 to get insta replies.
igmp_raw = igmp_raw .. bin.pack(">C", 0x10)
-- Number of sources (in the next arrays) = 1 ( Our IP only)
igmp_raw = igmp_raw .. bin.pack(">S", 0x01)
-- Source = Our IP address
igmp_raw = igmp_raw .. bin.pack(">I", ipOps.todword(interface.address))
end
igmp_raw = igmp_raw:sub(1,2) .. bin.pack(">S", packet.in_cksum(igmp_raw)) .. igmp_raw:sub(5)
return igmp_raw
end
local igmpQuery;
--- Sends an IGMP Membership query.
-- @param interface Network interface to send on.
-- @param vesion IGMP version. Could be 1, 2, 3 or all.
igmpQuery = function(interface, version)
local srcip = interface.address
local dstip = "224.0.0.1"
if version == 'all' then
-- Small pause to let listener begin and not miss reports.
stdnse.sleep(0.5)
igmpQuery(interface, 3)
igmpQuery(interface, 2)
igmpQuery(interface, 1)
else
local igmp_raw = igmpRaw(interface, version)
local ip_raw = bin.pack("H", "45c00040ed780000010218bc0a00c8750a00c86b") .. igmp_raw
local igmp_packet = packet.Packet:new(ip_raw, ip_raw:len())
igmp_packet:ip_set_bin_src(ipOps.ip_to_str(srcip))
igmp_packet:ip_set_bin_dst(ipOps.ip_to_str(dstip))
igmp_packet:ip_set_len(#igmp_packet.buf)
igmp_packet:ip_count_checksum()
local sock = nmap.new_dnet()
sock:ethernet_open(interface.device)
-- Ethernet IPv4 multicast, our ethernet address and type IP
local eth_hdr = bin.pack("HAH", "01 00 5e 00 00 01", interface.mac, "08 00")
sock:ethernet_send(eth_hdr .. igmp_packet.buf)
sock:ethernet_close()
end
end
-- Function to compare wieght of an IGMP response message.
-- Used to sort elements in responses table.
local respCompare = function(a,b)
return ipOps.todword(a.src) + a.type + (a.ngroups or ipOps.todword(a.group))
< ipOps.todword(b.src) + b.type + (b.ngroups or ipOps.todword(b.group))
end
local mgroup_names_fetch = function(filename)
local groupnames_db = {}
local file = io.open(filename, "r")
if not file then
return false
end
for l in file:lines() do
groupnames_db[#groupnames_db + 1] = stdnse.strsplit("\t", l)
end
file:close()
return groupnames_db
end
local mgroup_name_identify = function(db, ip)
--stdnse.print_debug("%s: '%s'", SCRIPT_NAME, ip)
for _, mg in ipairs(db) do
local ip1 = mg[1]
local ip2 = mg[2]
local desc = mg[3]
--stdnse.print_debug("%s: try: %s <= %s <= %s (%s)", SCRIPT_NAME, ip1, ip, ip2, desc)
if (not ipOps.compare_ip(ip, "lt", ip1) and not ipOps.compare_ip(ip2, "lt", ip)) then
--stdnse.print_debug("%s: found! %s <= %s <= %s (%s)", SCRIPT_NAME, ip1, ip, ip2, desc)
return desc
end
end
return false
end
action = function(host, port)
local timeout = stdnse.parse_timespec(stdnse.get_script_args(SCRIPT_NAME .. ".timeout"))
local version = stdnse.get_script_args(SCRIPT_NAME .. ".version") or 2
local interface = stdnse.get_script_args(SCRIPT_NAME .. ".interface")
timeout = (timeout or 7) * 1000
if version ~= 'all' then
version = tonumber(version)
end
local responses, results, interfaces, lthreads = {}, {}, {}, {}
local result, grouptable, sourcetable
local group_names_fname = stdnse.get_script_args(SCRIPT_NAME .. ".mgroupnamesdb") or
nmap.fetchfile("nselib/data/mgroupnames.db")
local mg_names_db = group_names_fname and mgroup_names_fetch(group_names_fname)
-- Check the interface
interface = interface or nmap.get_interface()
if interface then
-- Get the interface information
interface = nmap.get_interface_info(interface)
if not interface then
return ("ERROR: Failed to retreive %s interface information."):format(interface)
end
interfaces = {interface}
stdnse.print_debug("%s: Will use %s interface.", SCRIPT_NAME, interface.shortname)
else
local ifacelist = nmap.list_interfaces()
for _, iface in ipairs(ifacelist) do
-- Match all ethernet interfaces
if iface.address and iface.link=="ethernet" and
iface.address:match("%d+%.%d+%.%d+%.%d+") then
stdnse.print_debug("%s: Will use %s interface.", SCRIPT_NAME, iface.shortname)
table.insert(interfaces, iface)
end
end
end
-- We should iterate over interfaces
for _, interface in pairs(interfaces) do
local co = stdnse.new_thread(igmpListener, interface, timeout, responses)
igmpQuery(interface, version)
lthreads[co] = true
end
local condvar = nmap.condvar(responses)
-- Wait for the listening threads to finish
repeat
for thread in pairs(lthreads) do
if coroutine.status(thread) == "dead" then lthreads[thread] = nil end
end
if ( next(lthreads) ) then
condvar("wait")
end
until next(lthreads) == nil;
-- Output useful info from the responses
if #responses > 0 then
-- We should sort our list here.
-- This is useful to have consistent results for tools such as Ndiff.
table.sort(responses, respCompare)
for _, response in pairs(responses) do
result = {}
result.name = response.src
table.insert(result, "Interface: " .. response.interface)
-- Add to new targets if newtargets script arg provided
if target.ALLOW_NEW_TARGETS then target.add(response.src) end
if response.type == 0x12 then
table.insert(result, "Version: 1")
table.insert(result, "Multicast group: ".. response.group)
elseif response.type == 0x16 then
table.insert(result, "Version: 2")
table.insert(result, "Group: ".. response.group)
local mg_desc = mgroup_name_identify(mg_names_db, response.group)
if mg_desc then
table.insert(result, "Description: ".. mg_desc)
end
elseif response.type == 0x22 then
table.insert(result, "Version: 3")
for _, group in pairs(response.groups) do
grouptable = {}
grouptable.name = "Group: " .. group.address
if group.mode == 0x01 then
table.insert(grouptable, "Mode: INCLUDE")
elseif group.mode == 0x02 then
table.insert(grouptable, "Mode: EXCLUDE")
end
local mg_desc = mgroup_name_identify(mg_names_db, group.address)
if mg_desc then
table.insert(grouptable, "Description: ".. mg_desc)
end
if group.nsrc > 0 then
sourcetable = {}
sourcetable.name = "Sources:"
table.insert(sourcetable, group.src)
table.insert(grouptable, sourcetable)
end
table.insert(result, grouptable)
end
end
table.insert(results, result)
end
if #results>0 and not target.ALLOW_NEW_TARGETS then
table.insert(results,"Use the newtargets script-arg to add the results as targets")
end
return stdnse.format_output(true, results)
end
end
@KyuuKazami