Fix for bug that would make Nmap fail to run when compile without SSL support.

The wsdd library incorrectly assumed OpenSSL to always be available and the
ssh-hostkey used the undeclared SCRIPT_NAME in message when evaluating SSL
support. The bug was reported by Michael Pattrick on nmap-dev:
http://seclists.org/nmap-dev/2011/q1/312

[Patrik]

nselib/wsdd.lua

@@ -34,9 +34,14 @@
 
 module(... or "wsdd", package.seeall)
 
-require 'openssl'
 require 'target'
 
+local HAVE_SSL = false
+
+if pcall(require,'openssl') then
+  HAVE_SSL = true
+end
+
 -- The different probes
 local probes = {
 	
@@ -332,6 +337,8 @@ Helper = {
 	-- @return matches table containing responses, suitable for printing using
 	--         the <code>stdnse.format_output</code> function
 	discoverServices = function( self, probename )
+		if ( not(HAVE_SSL) ) then return false, "The wsdd library requires OpenSSL"	end
+	
 		local comm = Comm:new(self.host, self.port, self.mcast)
 		local probe = Util.getProbeByName(probename)
 		comm:setProbe( probe )

scripts/ssh-hostkey.nse

@@ -51,7 +51,7 @@ else
   portrule = function() return false end
   action = function() end
   stdnse.print_debug( 3, "Skipping %s script because OpenSSL is missing.",
-      SCRIPT_NAME)
+      filename)
   return;
 end