support for preferred nop

git-svn-id: file:///home/svn/incoming/trunk@3399 4d416f70-5f16-0410-b530-b9f4589650da

lib/msf/core/encoded_payload.rb

@@ -196,7 +196,17 @@ class EncodedPayload
 
 		# Now construct the actual sled
 		if (self.nop_sled_size > 0)
-			pinst.compatible_nops.each { |nopname, nopmod|
+			nops = pinst.compatible_nops
+
+			# If the caller had a preferred nop, try to find it and prefix it
+			if ((reqs['Nop']) and
+			    (preferred = framework.encoders[reqs['Nop']]))
+				encoders.unshift([reqs['Nop'], preferred ])
+			elsif (reqs['Nop'])
+				wlog("#{pinst.refname}: Failed to find preferred nop #{reqs['Nop']}")
+			end
+
+			nops.each { |nopname, nopmod|
 				# Create an instance of the nop module
 				self.nop = nopmod.new
 

lib/msf/core/exploit.rb

@@ -368,6 +368,7 @@ class Exploit < Msf::Module
 		reqs['MaxNops']        = payload_max_nops
 		reqs['MinNops']        = payload_min_nops
 		reqs['Encoder']        = datastore['Encoder']
+		reqs['Nop']            = datastore['Nop']
 		reqs['EncoderType']    = payload_encoder_type
 		reqs['EncoderOptions'] = payload_encoder_options