metasploit-framework/lib/net/ssh/command_stream.rb

# -*- coding: binary -*-
require 'rex'

module Net
module SSH

class CommandStream

	attr_accessor :channel, :thread, :error, :ssh
	attr_accessor :lsock, :rsock, :monitor

	module PeerInfo
		include ::Rex::IO::Stream
		attr_accessor :peerinfo
		attr_accessor :localinfo
	end

	def initialize(ssh, cmd, cleanup = false)

		self.lsock, self.rsock = Rex::Socket.tcp_socket_pair()
		self.lsock.extend(Rex::IO::Stream)
		self.lsock.extend(PeerInfo)
		self.rsock.extend(Rex::IO::Stream)

		self.ssh = ssh
		self.thread = Thread.new(ssh,cmd,cleanup) do |rssh,rcmd,rcleanup|

			begin
				info = rssh.transport.socket.getpeername
				self.lsock.peerinfo  = "#{info[1]}:#{info[2]}"

				info = rssh.transport.socket.getsockname
				self.lsock.localinfo = "#{info[1]}:#{info[2]}"

				rssh.open_channel do |rch|
					rch.exec(rcmd) do |c, success|
						raise "could not execute command: #{rcmd.inspect}" unless success

						c[:data] = ''

						c.on_eof do
							self.rsock.close rescue nil
							self.ssh.close rescue nil
							self.thread.kill
						end

						c.on_close do
							self.rsock.close rescue nil
							self.ssh.close rescue nil
							self.thread.kill
						end

						c.on_data do |ch,data|
							self.rsock.write(data)
						end

						c.on_extended_data do |ch, ctype, data|
							self.rsock.write(data)
						end

						self.channel = c
					end
				end

				self.monitor = Thread.new do
					while(true)
						next if not self.rsock.has_read_data?(1.0)
						buff = self.rsock.read(16384)
						break if not buff
						verify_channel
						self.channel.send_data(buff) if buff
					end
				end

				while true
					rssh.process(0.5) { true }
				end

			rescue ::Exception => e
				self.error = e
				#::Kernel.warn "BOO: #{e.inspect}"
				#::Kernel.warn e.backtrace.join("\n")
			ensure
				self.monitor.kill if self.monitor
			end

			# Shut down the SSH session if requested
			if(rcleanup)
				rssh.close
			end
		end
	end

	#
	# Prevent a race condition
	#
	def verify_channel
		while ! self.channel
			raise EOFError if ! self.thread.alive?
			::IO.select(nil, nil, nil, 0.10)
		end
	end

end
end
end