[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/internal/routemanager/client.go

@@ -302,7 +302,7 @@ func (c *clientNetwork) recalculateRouteAndUpdatePeerAndSystem(rsn reason) error
 
 	// If the chosen route is the same as the current route, do nothing
 	if c.currentChosen != nil && c.currentChosen.ID == newChosenID &&
-		c.currentChosen.IsEqual(c.routes[newChosenID]) {
+		c.currentChosen.Equal(c.routes[newChosenID]) {
 		return nil
 	}
 

client/internal/routemanager/ipfwdstate/ipfwdstate.go

@@ -0,0 +1,51 @@
+package ipfwdstate
+
+import (
+	"fmt"
+
+	log "github.com/sirupsen/logrus"
+
+	"github.com/netbirdio/netbird/client/internal/routemanager/systemops"
+)
+
+// IPForwardingState is a struct that keeps track of the IP forwarding state.
+// todo: read initial state of the IP forwarding from the system and reset the state based on it
+type IPForwardingState struct {
+	enabledCounter int
+}
+
+func NewIPForwardingState() *IPForwardingState {
+	return &IPForwardingState{}
+}
+
+func (f *IPForwardingState) RequestForwarding() error {
+	if f.enabledCounter != 0 {
+		f.enabledCounter++
+		return nil
+	}
+
+	if err := systemops.EnableIPForwarding(); err != nil {
+		return fmt.Errorf("failed to enable IP forwarding with sysctl: %w", err)
+	}
+	f.enabledCounter = 1
+	log.Info("IP forwarding enabled")
+
+	return nil
+}
+
+func (f *IPForwardingState) ReleaseForwarding() error {
+	if f.enabledCounter == 0 {
+		return nil
+	}
+
+	if f.enabledCounter > 1 {
+		f.enabledCounter--
+		return nil
+	}
+
+	// if failed to disable IP forwarding we anyway decrement the counter
+	f.enabledCounter = 0
+
+	// todo call systemops.DisableIPForwarding()
+	return nil
+}

client/internal/routemanager/server_nonandroid.go

@@ -13,7 +13,6 @@ import (
 	firewall "github.com/netbirdio/netbird/client/firewall/manager"
 	"github.com/netbirdio/netbird/client/internal/peer"
 	"github.com/netbirdio/netbird/client/internal/routemanager/iface"
-	"github.com/netbirdio/netbird/client/internal/routemanager/systemops"
 	"github.com/netbirdio/netbird/route"
 )
 
@@ -41,7 +40,7 @@ func (m *serverRouter) updateRoutes(routesMap map[route.ID]*route.Route) error {
 
 	for routeID := range m.routes {
 		update, found := routesMap[routeID]
-		if !found || !update.IsEqual(m.routes[routeID]) {
+		if !found || !update.Equal(m.routes[routeID]) {
 			serverRoutesToRemove = append(serverRoutesToRemove, routeID)
 		}
 	}
@@ -71,9 +70,6 @@ func (m *serverRouter) updateRoutes(routesMap map[route.ID]*route.Route) error {
 	}
 
 	if len(m.routes) > 0 {
-		if err := systemops.EnableIPForwarding(); err != nil {
-			return fmt.Errorf("enable ip forwarding: %w", err)
-		}
 		if err := m.firewall.EnableRouting(); err != nil {
 			return fmt.Errorf("enable routing: %w", err)
 		}