Fixes #4558. Since the arp spoofer is the only module that actually uses lookupaddrs, don't require every other pcaprub module to check for it.

git-svn-id: file:///home/svn/framework3/trunk@12672 4d416f70-5f16-0410-b530-b9f4589650da

lib/msf/core/exploit/capture.rb

@@ -376,15 +376,19 @@ module Exploit::Capture
 		if not @pcaprub_loaded
 			print_status("The Pcaprub module is not available: #{@pcaprub_error}")
 			raise RuntimeError, "Pcaprub not available"
-		#Those methods have been added later
-		elsif (not Pcap.respond_to? "lookupaddrs")
-			print_status("The Pcaprub module is not up-to-date")
-			raise RuntimeError, "The Pcaprub module is missing some functions"
 		else
 			true
 		end
 	end
 
+	# lookupaddr is not available in pcaprub 0.9.2 and prior,
+	# which is going to be installed in a lot of places. Modules
+	# which want it should check explicitly for it. TODO: Bug upstream
+	# to release it for real in 0.9.3
+	def lookupaddr_implemented?
+		@pcaprub_loaded and Pcap.respond_to?(:lookupaddrs)
+	end
+
 	def lookupnet
 		check_pcaprub_loaded
 		dev  = datastore['INTERFACE'] || ::Pcap.lookupdev

modules/auxiliary/spoof/arp/arp_poisoning.rb

@@ -109,7 +109,10 @@ class Metasploit3 < Msf::Auxiliary
 		lsmac = datastore['LOCALSMAC'] || @smac
 		raise RuntimeError ,'Local Source Mac is not in correct format' unless is_mac?(lsmac)
 
-		sip = datastore['LOCALSIP'] || Pcap.lookupaddrs(@interface)[0]
+		sip = datastore['LOCALSIP']
+		if lookupaddr_implemented? 
+			sip ||= Pcap.lookupaddrs(@interface)[0]
+		end
 		raise "LOCALIP is not an ipv4 address" unless is_ipv4? sip
 
 		dhosts_range = Rex::Socket::RangeWalker.new(datastore['DHOSTS'])