added the concept of payload convention

git-svn-id: file:///home/svn/incoming/trunk@2925 4d416f70-5f16-0410-b530-b9f4589650da

lib/msf/core/payload.rb

@@ -96,6 +96,39 @@ class Payload < Msf::Module
 		return module_info['Payload']['Offsets']
 	end
 
+	#
+	# Returns the staging convention that the payload uses, if any.  This is
+	# used to make sure that only compatible stagers and stages are built
+	# (where assumptions are made about register/environment initialization
+	# state and hand-off).
+	#
+	def convention
+		module_info['Convention']
+	end
+
+	#
+	# Checks to see if the supplied convention is compatible with this
+	# payload's convention.
+	#
+	def compatible_convention?(conv)
+		# If we ourself don't have a convention or our convention is equal to
+		# the one supplied, then we know we are compatible.
+		if ((self.convention == nil) or
+		    (self.convention == conv))
+			true
+		# On the flip side, if we are a stager and the supplied convention is
+		# nil, then we know it's compatible.
+		elsif ((payload_type == Type::Stager) and
+		       (conv == nil))
+			true
+		# Otherwise, the conventions don't match in some way or another, and as
+		# such we deem ourself as not being compatible with the supplied
+		# convention.
+		else
+			false
+		end
+	end
+
 	#
 	# Return the connection associated with this payload, or none if there
 	# isn't one.

lib/msf/core/payload_set.rb

@@ -91,11 +91,11 @@ class PayloadSet < ModuleSet
 
 		# Recalculate stagers and stages
 		_stagers.each_pair { |stager_name, p|
-			stager_mod, handler, stager_platform, stager_arch = p
+			stager_mod, handler, stager_platform, stager_arch, stager_conv = p
 
 			# Walk the array of stages
 			_stages.each_pair { |stage_name, p|
-				stage_mod, junk, stage_platform, stage_arch = p
+				stage_mod, junk, stage_platform, stage_arch, stage_conv = p
 
 				# No intersection between architectures on the payloads?
 				if ((stager_arch) and
@@ -119,6 +119,17 @@ class PayloadSet < ModuleSet
 					next
 				end
 
+				# If the stage has a convention, make sure it's compatible with
+				# the stager's
+				if ((stage_conv) and
+				    (stager_conv != stage_conv))
+					dlog("Stager #{stager_name} and stage #{stage_name} have incompatible conventions:",
+						'core', LEV_3)
+					dlog("  Stager: #{stager_conv}.", 'core', LEV_3)
+					dlog("  Stage: #{stage_conv}.", 'core', LEV_3)
+					next
+				end
+
 				# Build the payload dupe using the handler, stager,
 				# and stage
 				p = build_payload(handler, stager_mod, stage_mod)
@@ -173,7 +184,8 @@ class PayloadSet < ModuleSet
 				pmodule,
 				instance.handler,
 				instance.platform,
-				instance.arch
+				instance.arch,
+				instance.convention
 			]
 
 		# Use the module's preferred alias if it has one