support iterating across RHOSTS for exploits

lib/msf/ui/console/command_dispatcher/exploit.rb

@@ -46,8 +46,9 @@ class Exploit
     "Exploit"
   end
 
-  def exploit_single(opts)
+  def exploit_single(opts, rhost)
     begin
+      mod.datastore['RHOST'] = rhost
       session = mod.exploit_simple(opts)
     rescue ::Interrupt
       raise $!
@@ -176,7 +177,9 @@ class Exploit
       opts['Payload'] = Exploit.choose_payload(mod, opts['Target'])
     end
 
-    exploit_single(opts)
+    Rex::Socket::RangeWalker.new(mod.datastore['RHOSTS']).each do |rhost|
+      exploit_single(opts, rhost)
+    end
   end
 
   alias cmd_run cmd_exploit