#!/usr/bin/env ruby

require 'rex/post/meterpreter/extensions/sniffer/tlv'
require 'rex/proto/smb/utils'

module Rex
module Post
module Meterpreter
module Extensions
module Sniffer

###
#
# This meterpreter extension can be used to capture remote traffic
#
###
class Sniffer < Extension


	def initialize(client)
		super(client, 'sniffer')

		client.register_extension_aliases(
			[
				{ 
					'name' => 'sniffer',
					'ext'  => self
				},
			])
	end


	# Enumerate the remote sniffable interfaces
	def interfaces()
		ifaces = []
		ifacei = 0
		request = Packet.create_request('sniffer_interfaces')
		response = client.send_request(request)
		response.each(TLV_TYPE_SNIFFER_INTERFACES) { |p|
			vals  = p.tlvs.map{|x| x.value }
			iface = { }
			ikeys = %W{idx name description type mtu wireless usable dhcp}
			ikeys.each_index { |i| iface[ikeys[i]] = vals[i] }
			ifaces << iface
		}		
		return ifaces
	end
	
	# Start a packet capture on an opened interface
	def capture_start(intf,maxp=200000,filter="")
		request = Packet.create_request('sniffer_capture_start')
		request.add_tlv(TLV_TYPE_SNIFFER_INTERFACE_ID, intf.to_i)
		request.add_tlv(TLV_TYPE_SNIFFER_PACKET_COUNT, maxp.to_i)
		request.add_tlv(TLV_TYPE_SNIFFER_ADDITIONAL_FILTER, filter) if filter.length
		response = client.send_request(request)	
	end
	
	# Stop an active packet capture
	def capture_stop(intf)
		request = Packet.create_request('sniffer_capture_stop')
		request.add_tlv(TLV_TYPE_SNIFFER_INTERFACE_ID, intf.to_i)
		response = client.send_request(request)	
	end
	
	# Retrieve stats about a current capture
	def capture_stats(intf)
		request = Packet.create_request('sniffer_capture_stats')
		request.add_tlv(TLV_TYPE_SNIFFER_INTERFACE_ID, intf.to_i)
		response = client.send_request(request)
		{
			:packets => response.get_tlv_value(TLV_TYPE_SNIFFER_PACKET_COUNT),
			:bytes   => response.get_tlv_value(TLV_TYPE_SNIFFER_BYTE_COUNT),
		}
	end
	
	# Buffer the current capture to a readable buffer
	def capture_dump(intf)
		request = Packet.create_request('sniffer_capture_dump')
		request.add_tlv(TLV_TYPE_SNIFFER_INTERFACE_ID, intf.to_i)
		response = client.send_request(request, 3600)
		{
			:packets => response.get_tlv_value(TLV_TYPE_SNIFFER_PACKET_COUNT),
			:bytes   => response.get_tlv_value(TLV_TYPE_SNIFFER_BYTE_COUNT),
		}
	end
	
	# Retrieve the packet data for the specified capture
	def capture_dump_read(intf, len=16384)
		request = Packet.create_request('sniffer_capture_dump_read')
		request.add_tlv(TLV_TYPE_SNIFFER_INTERFACE_ID, intf.to_i)
		request.add_tlv(TLV_TYPE_SNIFFER_BYTE_COUNT, len.to_i)		
		response = client.send_request(request, 3600)
		{
			:bytes   => response.get_tlv_value(TLV_TYPE_SNIFFER_BYTE_COUNT),
			:data    => response.get_tlv_value(TLV_TYPE_SNIFFER_PACKET)
		}
	end
		
end

end; end; end; end; end
