#!/usr/bin/env ruby
# -*- coding: binary -*-

require 'rex/post/meterpreter/extensions/stdapi/tlv'
require 'rex/post/meterpreter/extensions/stdapi/net/route'
require 'rex/post/meterpreter/extensions/stdapi/net/interface'

module Rex
module Post
module Meterpreter
module Extensions
module Stdapi
module Net

###
#
# This class provides an interface to the network configuration
# that exists on the remote machine, such as interfaces, and
# routes.
#
###
class Config

	##
	#
	# Constructor
	#
	##

	#
	# Initializes a Config instance that is used to get information about the
	# network configuration of the remote machine.
	#
	def initialize(client)
		self.client = client
	end

	##
	#
	# Interfaces
	#
	##

	#
	# Enumerates each interface.
	#
	def each_interface(&block)
		get_interfaces().each(&block)
	end

	#
	# Returns an array of network interfaces with each element.
	#
	# being an Interface
	def get_interfaces
		request = Packet.create_request('stdapi_net_config_get_interfaces')
		ifaces  = []

		response = client.send_request(request)

		response.each(TLV_TYPE_NETWORK_INTERFACE) { |iface|
			addrs = []
			netmasks = []
			scopes = []
			while (a = iface.get_tlv_value(TLV_TYPE_IP, addrs.length))
				# Netmasks aren't tightly associated with addresses, they're
				# just thrown all together in the interface TLV ordered to
				# match up. This could be done better by creating another
				# GroupTlv type for addresses containing an address, a netmask,
				# and possibly a scope.
				n = iface.get_tlv_value(TLV_TYPE_NETMASK, addrs.length)
				if (n.nil?)
					# Some systems can't report a netmask, only a network
					# prefix, so figure out the netmask from that.
					n = iface.get_tlv_value(TLV_TYPE_IP_PREFIX, addrs.length)
					if n
						n = Rex::Socket.bit2netmask(n, !!(a.length == 16))
					end
				else
					n = Rex::Socket.addr_ntoa(n)
				end
				s = iface.get_tlv_value(TLV_TYPE_IP6_SCOPE, addrs.length)
				scopes[addrs.length] = s if s
				netmasks[addrs.length] = n if n
				addrs << Rex::Socket.addr_ntoa(a)
			end
			ifaces << Interface.new(
					:index    => iface.get_tlv_value(TLV_TYPE_INTERFACE_INDEX),
					:mac_addr => iface.get_tlv_value(TLV_TYPE_MAC_ADDRESS),
					:mac_name => iface.get_tlv_value(TLV_TYPE_MAC_NAME),
					:mtu      => iface.get_tlv_value(TLV_TYPE_INTERFACE_MTU),
					:flags    => iface.get_tlv_value(TLV_TYPE_INTERFACE_FLAGS),
					:addrs    => addrs,
					:netmasks => netmasks,
					:scopes   => scopes
				)
		}

		return ifaces
	end

	alias interfaces get_interfaces

	##
	#
	# Routing
	#
	##

	#
	# Enumerates each route.
	#
	def each_route(&block)
		get_routes().each(&block)
	end

	#
	# Returns an array of routes with each element being a Route.
	#
	def get_routes
		request = Packet.create_request('stdapi_net_config_get_routes')
		routes  = []

		response = client.send_request(request)

		# Build out the array of routes
		# Note: This will include both IPv4 and IPv6 routes
		response.each(TLV_TYPE_NETWORK_ROUTE) { |route|
			routes << Route.new(
					route.get_tlv_value(TLV_TYPE_SUBNET),
					route.get_tlv_value(TLV_TYPE_NETMASK),
					route.get_tlv_value(TLV_TYPE_GATEWAY),
					route.get_tlv_value(TLV_TYPE_STRING),
					route.get_tlv_value(TLV_TYPE_ROUTE_METRIC))
		}

		return routes
	end

	alias routes get_routes

	#
	# Adds a route to the target machine.
	#
	def add_route(subnet, netmask, gateway)
		request = Packet.create_request('stdapi_net_config_add_route')

		request.add_tlv(TLV_TYPE_SUBNET_STRING, subnet)
		request.add_tlv(TLV_TYPE_NETMASK_STRING, netmask)
		request.add_tlv(TLV_TYPE_GATEWAY_STRING, gateway)

		response = client.send_request(request)

		return true
	end

	#
	# Removes a route from the target machine.
	#
	def remove_route(subnet, netmask, gateway)
		request = Packet.create_request('stdapi_net_config_remove_route')

		request.add_tlv(TLV_TYPE_SUBNET_STRING, subnet)
		request.add_tlv(TLV_TYPE_NETMASK_STRING, netmask)
		request.add_tlv(TLV_TYPE_GATEWAY_STRING, gateway)

		response = client.send_request(request)

		return true
	end

protected

	attr_accessor :client # :nodoc:

end

end; end; end; end; end; end