#!/bin/bash

$NFT -f - <<EOF
table inet t {
	set s {
		type ipv4_addr . inet_service
		size 65536
		flags dynamic,timeout
		elements = { 192.168.7.1 . 22 }
	}

	chain c {
		tcp dport 21 add @s { ip saddr . 22 timeout 60s }
	}
}
EOF