local eigrp = require "eigrp" local nmap = require "nmap" local stdnse = require "stdnse" local table = require "table" local packet = require "packet" local ipOps = require "ipOps" local target = require "target" local coroutine = require "coroutine" local string = require "string" description = [[ Performs network discovery and routing information gathering through Cisco's Enhanced Interior Gateway Routing Protocol (EIGRP). The script works by sending an EIGRP Hello packet with the specified Autonomous System value to the 224.0.0.10 multicast address and listening for EIGRP Update packets. The script then parses the update responses for routing information. If no A.S value was provided by the user, the script will listen for multicast Hello packets to grab an A.S value. If no interface was provided as a script argument or through the -e option, the script will send packets and listen through all valid ethernet interfaces simultaneously. ]] --- -- @usage -- nmap --script=broadcast-eigrp-discovery -- nmap --script=broadcast-eigrp-discovery -e wlan0 -- -- @args broadcast-eigrp-discovery.as Autonomous System value to announce on. -- If not set, the script will listen for announcements on 224.0.0.10 to grab -- an A.S value. -- -- @args broadcast-eigrp-discovery.timeout Max amount of time to listen for A.S -- announcements and updates. Defaults to 10 seconds. -- -- @args broadcast-eigrp-discovery.kparams the K metrics. -- Defaults to 101000. -- @args broadcast-eigrp-discovery.interface Interface to send on (overrides -e) -- --@output -- Pre-scan script results: -- | broadcast-eigrp-discovery: -- | 192.168.2.2 -- | Interface: eth0 -- | A.S: 1 -- | Virtual Router ID: 0 -- | Internal Route -- | Destination: 192.168.21.0/24 -- | Next hop: 0.0.0.0 -- | Internal Route -- | Destination: 192.168.31.0/24 -- | Next hop: 0.0.0.0 -- | External Route -- | Protocol: Static -- | Originating A.S: 0 -- | Originating Router ID: 192.168.31.1 -- | Destination: 192.168.60.0/24 -- | Next hop: 0.0.0.0 -- | External Route -- | Protocol: OSPF -- | Originating A.S: 1 -- | Originating Router ID: 192.168.31.1 -- | Destination: 192.168.24.0/24 -- | Next hop: 0.0.0.0 -- |_ Use the newtargets script-arg to add the results as targets -- author = "Hani Benhabiles" license = "Same as Nmap--See https://nmap.org/book/man-legal.html" categories = {"discovery", "broadcast", "safe"} prerule = function() if nmap.address_family() ~= 'inet' then stdnse.verbose1("is IPv4 only.") return false end if not nmap.is_privileged() then stdnse.verbose1("not running for lack of privileges.") return false end return true end -- Sends EIGRP raw packet to EIGRP multicast address. --@param interface Network interface to use. --@param eigrp_raw Raw eigrp packet. local eigrpSend = function(interface, eigrp_raw) local srcip = interface.address local dstip = "224.0.0.10" local ip_raw = stdnse.fromhex( "45c00040ed780000015818bc0a00c8750a00c86b") .. eigrp_raw local eigrp_packet = packet.Packet:new(ip_raw, ip_raw:len()) eigrp_packet:ip_set_bin_src(ipOps.ip_to_str(srcip)) eigrp_packet:ip_set_bin_dst(ipOps.ip_to_str(dstip)) eigrp_packet:ip_set_len(#eigrp_packet.buf) eigrp_packet:ip_count_checksum() local sock = nmap.new_dnet() sock:ethernet_open(interface.device) -- Ethernet IPv4 multicast, our ethernet address and packet type IP local eth_hdr = stdnse.fromhex("01 00 5e 00 00 0a") .. interface.mac .. stdnse.fromhex("08 00") sock:ethernet_send(eth_hdr .. eigrp_packet.buf) sock:ethernet_close() end -- Listens for EIGRP updates --@param interface Network interface to listen on. --@param timeout Ammount of time to listen for. --@param responses Table to put valid responses into. local eigrpListener = function(interface, timeout, responses) local condvar = nmap.condvar(responses) local routers = {} local status, l3data, response, p, eigrp_raw, _ local start = nmap.clock_ms() -- Filter for EIGRP packets that are sent either to us or to multicast local filter = "ip proto 88 and (ip dst host " .. interface.address .. " or 224.0.0.10)" local listener = nmap.new_socket() listener:set_timeout(500) listener:pcap_open(interface.device, 1024, true, filter) -- For each EIGRP packet captured until timeout while (nmap.clock_ms() - start) < timeout do response = {} response.tlvs = {} status, _, _, l3data = listener:pcap_receive() if status then p = packet.Packet:new(l3data, #l3data) eigrp_raw = string.sub(l3data, p.ip_hl*4 + 1) -- Check if it is an EIGRPv2 Update if eigrp_raw:byte(1) == 0x02 and eigrp_raw:byte(2) == 0x01 then -- Skip if did get the info from this router before if not routers[p.ip_src] then -- Parse header response = eigrp.EIGRP.parse(eigrp_raw) response.src = p.ip_src response.interface = interface.shortname end if response then -- See, if it has routing information for _,tlv in pairs(response.tlvs) do if eigrp.EIGRP.isRoutingTLV(tlv.type) then routers[p.ip_src] = true table.insert(responses, response) break end end end end end end condvar("signal") return end -- Listens for EIGRP announcements to grab a valid Autonomous System value. --@param interface Network interface to listen on. --@param timeout Max amount of time to listen for. --@param astab Table to put result into. local asListener = function(interface, timeout, astab) local condvar = nmap.condvar(astab) local status, l3data, p, eigrp_raw, eigrp_hello, _ local start = nmap.clock_ms() local filter = "ip proto 88 and ip dst host 224.0.0.10" local listener = nmap.new_socket() listener:set_timeout(500) listener:pcap_open(interface.device, 1024, true, filter) while (nmap.clock_ms() - start) < timeout do -- Check if another listener already found an A.S value. if #astab > 0 then break end status, _, _, l3data = listener:pcap_receive() if status then p = packet.Packet:new(l3data, #l3data) eigrp_raw = string.sub(l3data, p.ip_hl*4 + 1) -- Listen for EIGRPv2 Hello packets if eigrp_raw:byte(1) == 0x02 and eigrp_raw:byte(2) == 0x05 then eigrp_hello = eigrp.EIGRP.parse(eigrp_raw) if eigrp_hello and eigrp_hello.as then table.insert(astab, eigrp_hello.as) break end end end end condvar("signal") end local function fail (err) return stdnse.format_output(false, err) end action = function() -- Get script arguments local as = stdnse.get_script_args(SCRIPT_NAME .. ".as") local kparams = stdnse.get_script_args(SCRIPT_NAME .. ".kparams") or "101000" local timeout = stdnse.parse_timespec(stdnse.get_script_args(SCRIPT_NAME .. ".timeout")) local interface = stdnse.get_script_args(SCRIPT_NAME .. ".interface") local output, responses, interfaces, lthreads = {}, {}, {}, {} local result, response, route, eigrp_hello, k local timeout = (timeout or 10) * 1000 -- K params should be of length 6 -- Cisco routers ignore eigrp packets that don't have matching K parameters if #kparams < 6 or #kparams > 6 then return fail("kparams should be of size 6.") else k = {} k[1] = string.sub(kparams, 1,1) k[2] = string.sub(kparams, 2,2) k[3] = string.sub(kparams, 3,3) k[4] = string.sub(kparams, 4,4) k[5] = string.sub(kparams, 5,5) k[6] = string.sub(kparams, 6) end interface = interface or nmap.get_interface() if interface then -- If an interface was provided, get its information interface = nmap.get_interface_info(interface) if not interface then return fail(("Failed to retrieve %s interface information."):format(interface)) end interfaces = {interface} stdnse.debug1("Will use %s interface.", 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.debug1("Will use %s interface.", iface.shortname) table.insert(interfaces, iface) end end end -- If user didn't provide an Autonomous System value, we listen fro multicast -- HELLO router announcements to get one. if not as then -- We use a table for condvar local astab = {} stdnse.debug1("No A.S value provided, will sniff for one.") -- We should iterate over interfaces for _, interface in pairs(interfaces) do local co = stdnse.new_thread(asListener, interface, timeout, astab) lthreads[co] = true end local condvar = nmap.condvar(astab) -- 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; if #astab > 0 then stdnse.debug1("Will use %s A.S value.", astab[1]) as = astab[1] else return fail("Couldn't get an A.S value.") end end -- Craft Hello packet eigrp_hello = eigrp.EIGRP:new(eigrp.OPCODE.HELLO, as) -- K params eigrp_hello:addTLV({ type = eigrp.TLV.PARAM, k = k, htime = 15}) -- Software version eigrp_hello:addTLV({ type = eigrp.TLV.SWVER, majv = 12, minv = 4, majtlv = 1, mintlv = 2}) -- On each interface, launch the listening thread and send the Hello packet. lthreads = {} for _, interface in pairs(interfaces) do local co = stdnse.new_thread(eigrpListener, interface, timeout, responses) -- We insert a small delay before sending the Hello so the listening -- thread doesn't miss updates. stdnse.sleep(0.5) lthreads[co] = true eigrpSend(interface, tostring(eigrp_hello)) end local condvar = nmap.condvar(responses) -- Wait for the listening threads to finish repeat condvar("wait") for thread in pairs(lthreads) do if coroutine.status(thread) == "dead" then lthreads[thread] = nil end end until next(lthreads) == nil; -- Output the useful info from the responses if #responses > 0 then for _, response in pairs(responses) do result = {} result.name = response.src if target.ALLOW_NEW_TARGETS then target.add(response.src) end table.insert(result, "Interface: " .. response.interface) table.insert(result, ("A.S: %d"):format(response.as)) table.insert(result, ("Virtual Router ID: %d"):format(response.routerid)) -- Output routes information TLVs for _, tlv in pairs(response.tlvs) do route = {} -- We are only interested in Internal or external routes if tlv.type == eigrp.TLV.EXT then route.name = "External route" for name, value in pairs(eigrp.EXT_PROTO) do if value == tlv.eproto then table.insert(route, ("Protocol: %s"):format(name)) break end end table.insert(route, ("Originating A.S: %s"):format(tlv.oas)) table.insert(route, ("Originating Router ID: %s"):format(tlv.orouterid)) if target.ALLOW_NEW_TARGETS then target.add(tlv.orouterid) end table.insert(route, ("Destination: %s/%d"):format(tlv.dst, tlv.mask)) table.insert(route, ("Next hop: %s"):format(tlv.nexth)) table.insert(result, route) elseif tlv.type == eigrp.TLV.INT then route.name = "Internal route" table.insert(route, ("Destination: %s/%d"):format(tlv.dst, tlv.mask)) table.insert(route, ("Next hop: %s"):format(tlv.nexth)) table.insert(result, route) end end table.insert(output, result) end if #output>0 and not target.ALLOW_NEW_TARGETS then table.insert(output,"Use the newtargets script-arg to add the results as targets") end return stdnse.format_output(true, output) end end