/ip firewall filter

add chain=input action=drop protocol=tcp in-interface=lan dst-port=135-139,445

add chain=input action=drop protocol=udp in-interface=lan dst-port=135-139,445

add chain=forward action=drop protocol=tcp in-interface=lan dst-port=25,135,137-139,445,593,1025,4691,5933

add chain=forward action=drop protocol=udp in-interface=lan dst-port=25,135,137-139,445,593,1025,4691,5933

add chain=forward action=drop p2p=bit-torrent

add chain=forward action=accept connection-state=established

add chain=forward action=accept connection-state=related

add chain=forward action=drop connection-state=invalid