[client, management] Add port forwarding (#3275)

Add initial support to ingress ports on the client code.

- new types where added
- new protocol messages and controller

client/firewall/nftables/manager_linux.go

@@ -342,6 +342,22 @@ func (m *Manager) Flush() error {
 	return m.aclManager.Flush()
 }
 
+// AddDNATRule adds a DNAT rule
+func (m *Manager) AddDNATRule(rule firewall.ForwardRule) (firewall.Rule, error) {
+	m.mutex.Lock()
+	defer m.mutex.Unlock()
+
+	return m.router.AddDNATRule(rule)
+}
+
+// DeleteDNATRule deletes a DNAT rule
+func (m *Manager) DeleteDNATRule(rule firewall.Rule) error {
+	m.mutex.Lock()
+	defer m.mutex.Unlock()
+
+	return m.router.DeleteDNATRule(rule)
+}
+
 func (m *Manager) createWorkTable() (*nftables.Table, error) {
 	tables, err := m.rConn.ListTablesOfFamily(nftables.TableFamilyIPv4)
 	if err != nil {