* Improve logic of lua plugins:

 - fix once received plugin to configure properly (pointy hat to: dmx)
 - add additional functionality to once_received plugin for strict checking of received
 - make all things local

src/plugins/lua/once_received.lua

@@ -2,14 +2,63 @@
 
 local metric = 'default'
 local symbol = 'ONCE_RECEIVED'
+-- Symbol for strict checks
+local symbol_strict = nil
+local bad_hosts = {}
+local good_hosts = {}
 
 function check_quantity_received (task)
 	local recvh = task:get_received_headers()
+	print (symbol)
 	if table.maxn(recvh) <= 1 then
 		task:insert_result(metric, symbol, 1)
 	end
+	-- Strict checks
+	if symbol_strict then
+		local r = recvh[1]
+		-- Unresolved host
+		if not r['real_hostname'] or r['real_hostname'] == 'unknown' or string.match(r['real_hostname'], '(%d+)\.(%d+)\.(%d+)\.(%d+)') then
+			task:insert_result(metric, symbol_strict, 1)
+		end
+		local i = true
+		for _,h in ipairs(bad_hosts) do
+			if string.find(r['real_hostname'], h) then
+				-- Check for good hostname
+				for _,gh in ipairs(good_hosts) do
+					if string.find(r['real_hostname'], gh) then
+						i = false
+						break
+					end
+				end
+				if i then
+					task:insert_result(metric, symbol_strict, 1, h)
+					return
+				end
+			end
+		end
+	end
 end
 
-local m = rspamd_config:get_metric(metric)
-m:register_symbol(symbol, 1.0, 'check_quantity_received')
+-- Configuration
+local opts =  rspamd_config:get_all_opt('once_received')
+if opts then
+    if opts['symbol'] then
+        symbol = opts['symbol']
+
+	    for n,v in pairs(opts) do
+			if n == 'symbol_strict' then
+				symbol_strict = v
+			elseif n == 'bad_host' then
+			    table.insert(bad_hosts, v)
+			elseif n == 'good_host' then
+			    table.insert(good_hosts, v)
+		    elseif n == 'metric' then
+			    metric = v
+		    end
+	    end
+
+		-- Register symbol's callback
+		local m = rspamd_config:get_metric(metric)
+		m:register_symbol(symbol, 1.0, 'check_quantity_received')
+	end
+end

src/plugins/lua/received_rbl.lua

@@ -7,7 +7,6 @@
 --      symbol = "RECEIVED_RBL";
 -- };
 
-
 local metric = 'default'
 local symbol = 'RECEIVED_RBL'
 local rbls = {}
@@ -37,17 +36,19 @@ end
 -- Configuration
 local opts =  rspamd_config:get_all_opt('received_rbl')
 if opts then
-	for n,v in pairs(opts) do
-		if n == 'rbl' then
-			table.insert(rbls, v)
-		elseif n == 'metric' then
-			metric = v
-		elseif n == 'symbol' then
-			symbol = v
-		end
-	end
-end
+    if opts['symbol'] then
+        symbol = opts['symbol']
 
-local m = rspamd_config:get_metric(metric)
-m:register_symbol(symbol, 1.0, 'received_cb')
+	    for n,v in pairs(opts) do
+		    if n == 'rbl' then
+			    table.insert(rbls, v)
+		    elseif n == 'metric' then
+			    metric = v
+		    end
+	    end
+        -- Register symbol's callback
+        local m = rspamd_config:get_metric(metric)
+        m:register_symbol(symbol, 1.0, 'received_cb')
+    end
+    -- If no symbol defined, do not register this module
+end