O_BASIC_IP_SRC_MASK
(*cmd)->opcode = O_BASIC_IP_SRC_MASK;
keyword(MODULE_BASIC_ID, O_BASIC_IP_SRC_MASK, "from-[mask]", FROM);
function(MODULE_BASIC_ID, O_BASIC_IP_SRC_MASK,
O_BASIC_IP_SRC_MASK, (filter_func)check_from_mask);