o [NSE] Added a rsync library and two new script:

+ rsync-list-modules - list available rsync modules
  + rsync-brute - attempts to brute force passwords against a rsync module
  [Patrik]

scripts/rsync-list-modules.nse

@@ -0,0 +1,44 @@
+description = [[
+List modules available for rsync synchronization
+]]
+
+---
+-- @usage
+-- nmap -p 873 --script rsync-list-modules <ip>
+--
+-- @output
+-- PORT    STATE SERVICE
+-- 873/tcp open  rsync
+-- | rsync-list-modules: 
+-- |   www            	www directory
+-- |   log            	log directory
+-- |_  etc            	etc directory
+--
+
+require 'rsync'
+require 'shortport'
+
+author = "Patrik Karlsson"
+license = "Same as Nmap--See http://nmap.org/book/man-legal.html"
+categories = {"discovery", "safe"}
+
+portrule = shortport.port_or_service(873, "rsync", "tcp")
+
+action = function(host, port)
+	local helper = rsync.Helper:new(host, port, { module = "" })
+	if ( not(helper) ) then
+		return "\n  ERROR: Failed to create rsync.Helper"
+	end
+	
+	local status, err = helper:connect()
+	if ( not(status) ) then
+		return "\n  ERROR: Failed to connect to rsync server"
+	end
+	
+	local modules = {}
+	status, modules = helper:listModules()
+	if ( not(status) ) then
+		return "\n  ERROR: Failed to retrieve a list of modules"
+	end
+	return stdnse.format_output(true, modules)
+end