# -*- coding: binary -*-
module Msf
module Ui
module Web

module Comm

	class Channel
		def initialize
			@id = Comm.next_channel_id
		end

		def read
			nil
		end

		attr_accessor :id
	end

	class SessionChannel < Channel
		def initialize(session_id, pipe)
			super()

			@sid  = session_id
			@pipe = pipe

			@pipe.create_subscriber(channel.id)
		end

		def close
			@pipe.remove_subscriber(channel.id)
		end

		def write_input(msg)
			@pipe.write_input(msg)
		end

		def read
			@pipe.read_subscriber(channel.id)
		end
	end

	class SessionEventSubscriber
		include Msf::SessionEvent

		def on_session_open(session)
			pipe = Comm.create_session_pipe(session)

			session.init_ui(pipe, pipe)
		end
	end

	@@framework     = nil
	@@channels      = {}
	@@channel_id    = 0
	@@read_event    = Rex::Sync::Event.new(false, false)
	@@session_pipes = {}

	def self.setup(framework)
		@framework = framework

		framework.events.add_session_subscriber(SessionEventSubscriber.new)
	end

	def self.wakeup
		@read_event.set
	end

	def self.next_channel_id
		@channel_id += 1
	end

	def self.create_channel(client, request)
		create_session_channel(client.qstring['sid'].to_i)
	end

	def self.create_session_channel(session_id)
		channel = SessionChannel.new(session_id, @session_pipes[session_id])

		@channels[channel.id] = channel

		channel
	end

	def self.create_session_pipe(session)
		pipe = Rex::IO::BidirectionalPipe.new

		@session_pipes[session.id] = pipe

		pipe
	end

	def self.write_channel(client, request)
		channel_id = request.qstring['channel_id']
		data       = request.qstring['data']
		channel    = @channels[channel_id]

		if channel.nil? == false
			channel.write_input(data)
		end
	end

	def self.read_channels(client, request)
		dlog("read_channels: waiting for event")

		# Wait to see if there's any data available on channels.  If there
		# isn't, then we send a response immediately.  Otherwise, we check
		# to see if any of the requested channels were ones that we're
		# interested in.
		begin
			@@read_event.wait(15)
		rescue Timeout::Error
			client.send_response(Rex::Proto::Http::Response::OK.new)
			return
		end

		@@read_event.reset

		channels = request.qstring['channels']

		if channels.kind_of?(Array) == false
			channels = [channels]
		end

		# Walk each channel, checking to see if there is any read data.  If
		# there is, then we'll include it in the response body.
		body = '<channeldatum>'

		channels.each { |cid|
			channel = @channels[cid]

			next if channel.nil?

			buf = channel.read

			next if buf.nil?

			body += "<channeldata id=\"#{channel.id}\">#{Base64.encode64(buf)}</channeldata>"
		}

		body = '</channeldatum>'

		# Create and send the response
		response = Rex::Proto::Http::Response::OK.new
		response.body = body

		client.send_response(response)
	end

end

end
end
end