require 'msf/core'

module Msf

###
#
# ExploitEvents
# -------------
#
# Event notifications that affect exploits.
#
###
module ExploitEvents

	#
	# Notified when an exploit is successful
	#
	def on_exploit_success(exploit)
	end

	#
	# Notified when an exploit is unsuccessful
	#
	def on_exploit_failure(exploit, reason)
	end

end

###
#
# Exploit
# -------
#
# The exploit class acts as the base class for all exploit modules.  It
# provides a common interface for interacting with exploits at the most basic
# level.
#
###
class Exploit < Msf::Module

	#
	# The various check codes that can be returned from the ``check'' routine.
	#
	module CheckCode
		Safe        = [ 0, "The target is not exploitable." ]
		Detected    = [ 1, "The target service is running, but could not be validated." ]
		Appears     = [ 2, "The target appears to be vulnerable." ]
		Vulnerable  = [ 3, "The target is vulnerable." ]
		Unsupported = [ 4, "This exploit does not support check." ]
	end

	#
	# The various basic types of exploits
	#
	module Type
		Remote  = "remote"
		Local   = "local"
		Omni    = "omnipresent"
	end

	#
	# The types of stances an exploit can take, such as passive or aggressive.
	# Stances indicate whether or not the exploit triggers the exploit without
	# waiting for one or more conditions to be met (aggressive) or whether it
	# must wait for certain conditions to be satisfied before the exploit can
	# be initiated (passive)
	#
	module Stance
		Aggressive = "aggresive"
		Passive    = "passive"
	end

	#
	# Constructo the clown!  Watch as he kills small children with balloons.
	#
	def initialize(info = {})
		super(info)

		self.targets = Rex::Transformer.transform(info['Targets'], Array,
				[ Target ], 'Targets')
		self.default_target = info['DefaultTarget']
		self.payload = info['Payload'] || {}
	end

	##
	#
	# Core exploit interface
	# ----------------------
	#
	# These are the methods that exploits will override to perform various
	# tasks, such as checking a target to see if it's vulnerable, automatically
	# selecting a target, or performing an exploit.
	#
	##

	#
	# Checks to see if the target is vulnerable, returning unsupported if it's
	# not supported.
	#
	def check
		CheckCode::Unsupported
	end

	#
	# Kicks off the actual exploit.  Prior to this call, the framework will
	# have validated the data store using the options associated with this
	# exploit module.  It will also pre-generate the desired payload, though
	# exploits can re-generate the payload if necessary.
	#
	def exploit
	end

	##
	#
	# Feature detection
	# -----------------
	#
	# These methods check to see if there is a derived implementation of
	# various methods as a way of inferring whether or not a given exploit
	# supports the feature.
	#
	##

	def supports_check?
		derived_implementor?(Msf::Exploit, 'check')
	end

	def supports_exploit?
		derived_implementor?(Msf::Exploit, 'exploit')
	end

	#
	# Returns a hash of the capabilities this exploit module has
	#
	def capabilities
		{
			'check'       => supports_check?,
			'exploit'     => supports_exploit?
		}
	end

	##
	#
	# Getters/Setters and information collectors
	#
	##

	#
	# The module's type
	#
	def type
		MODULE_EXPLOIT
	end

	#
	# If we don't know the exploit type, then I guess it's omnipresent!
	#
	def exploit_type
		Type::Omni
	end

	#
	# Generally, all exploits take an aggressive stance.
	#
	def stance
		module_info['Stance'] || Stance::Aggressive
	end

	##
	#
	# Payload requirement wrappers
	#
	##

	#
	# Return any text that should be prepended to the payload.  The payload
	# module is passed so that the exploit can take a guess at architecture
	# and platform if it's a multi exploit.
	#
	def payload_prepend(payload_module)
		payload['Prepend'] || ''
	end

	#
	# Return any text that should be appended to the payload.  The payload
	# module is passed so that the exploit can take a guess at architecture
	# and platform if it's a multi exploit.
	#
	def payload_append(payload_module)
		payload['Append'] || ''
	end

	#
	# Return any text that should be prepended to the encoder of the payload.
	# The payload module is passed so that the exploit can take a guess 
	# at architecture and platform if it's a multi exploit.
	#
	def payload_prepend_encoder(payload_module)
		payload['PrependEncoder'] || ''
	end

	#
	# Returns the maximum amount of room the exploit has for a payload.
	#
	# TODO: make target based?  size differences per platform...
	#
	def payload_space
		payload['Space'].to_i
	end

	#
	# Returns the bad characters that cannot be in any payload used by this
	# exploit.
	#
	def payload_badchars
		payload['BadChars']
	end

	##
	#
	# NOP requirement wrappers
	#
	##

	#
	# Returns the list of registers that the NOP generator should save, 
	# if any.  It will use the current target's save registers in precedence
	# over those defined globally for the exploit module.
	#
	# If there are no save registers, nil is returned.
	#
	def nop_save_registers
		if (target and targets[target].save_registers)
			return targets[target].save_registers 
		else
			return module_info['SaveRegisters'] || nil
		end
	end

	#
	# Attributes
	#
	attr_accessor :target, :targets
	attr_reader   :default_target
	attr_reader   :payload

	###
	#
	# Local
	# -----
	#
	# The local exploit class is a specialization of the exploit module class that
	# is geared toward exploits that are performed locally.  Locally, in this
	# case, is defined as an exploit that is realized by means other than network
	# communication.
	#
	###
	class Local < Exploit
		def exploit_type
			Exploit::Type::Local
		end
	end

	###
	#
	# Remote
	# ------
	#
	# The remote exploit class is a specialization of the exploit module class
	# that is geared toward exploits that are performed against targets other than
	# the local machine.  This typically implies exploiting other machines via a
	# network connection, though it is not limited to this scope.
	#
	###
	class Remote < Exploit

		def exploit_type
			Exploit::Type::Remote
		end
	end

protected

	attr_writer :default_target
	attr_writer :payload

end

end

require 'msf/core/exploit/tcp'
require 'msf/core/exploit/dcerpc'