Rollback new routing functionality

client/internal/routemanager/systemops_nonandroid.go

@@ -0,0 +1,120 @@
+//go:build !android && !ios
+
+package routemanager
+
+import (
+	"fmt"
+	"net"
+	"net/netip"
+
+	"github.com/libp2p/go-netroute"
+	log "github.com/sirupsen/logrus"
+)
+
+var errRouteNotFound = fmt.Errorf("route not found")
+
+func addToRouteTableIfNoExists(prefix netip.Prefix, addr string) error {
+	ok, err := existsInRouteTable(prefix)
+	if err != nil {
+		return err
+	}
+	if ok {
+		log.Warnf("skipping adding a new route for network %s because it already exists", prefix)
+		return nil
+	}
+
+	ok, err = isSubRange(prefix)
+	if err != nil {
+		return err
+	}
+
+	if ok {
+		err := addRouteForCurrentDefaultGateway(prefix)
+		if err != nil {
+			log.Warnf("unable to add route for current default gateway route. Will proceed without it. error: %s", err)
+		}
+	}
+
+	return addToRouteTable(prefix, addr)
+}
+
+func addRouteForCurrentDefaultGateway(prefix netip.Prefix) error {
+	defaultGateway, err := getExistingRIBRouteGateway(netip.MustParsePrefix("0.0.0.0/0"))
+	if err != nil && err != errRouteNotFound {
+		return err
+	}
+
+	addr := netip.MustParseAddr(defaultGateway.String())
+
+	if !prefix.Contains(addr) {
+		log.Debugf("skipping adding a new route for gateway %s because it is not in the network %s", addr, prefix)
+		return nil
+	}
+
+	gatewayPrefix := netip.PrefixFrom(addr, 32)
+
+	ok, err := existsInRouteTable(gatewayPrefix)
+	if err != nil {
+		return fmt.Errorf("unable to check if there is an existing route for gateway %s. error: %s", gatewayPrefix, err)
+	}
+
+	if ok {
+		log.Debugf("skipping adding a new route for gateway %s because it already exists", gatewayPrefix)
+		return nil
+	}
+
+	gatewayHop, err := getExistingRIBRouteGateway(gatewayPrefix)
+	if err != nil && err != errRouteNotFound {
+		return fmt.Errorf("unable to get the next hop for the default gateway address. error: %s", err)
+	}
+	log.Debugf("adding a new route for gateway %s with next hop %s", gatewayPrefix, gatewayHop)
+	return addToRouteTable(gatewayPrefix, gatewayHop.String())
+}
+
+func existsInRouteTable(prefix netip.Prefix) (bool, error) {
+	routes, err := getRoutesFromTable()
+	if err != nil {
+		return false, err
+	}
+	for _, tableRoute := range routes {
+		if tableRoute == prefix {
+			return true, nil
+		}
+	}
+	return false, nil
+}
+
+func isSubRange(prefix netip.Prefix) (bool, error) {
+	routes, err := getRoutesFromTable()
+	if err != nil {
+		return false, err
+	}
+	for _, tableRoute := range routes {
+		if tableRoute.Bits() > minRangeBits && tableRoute.Contains(prefix.Addr()) && tableRoute.Bits() < prefix.Bits() {
+			return true, nil
+		}
+	}
+	return false, nil
+}
+
+func removeFromRouteTableIfNonSystem(prefix netip.Prefix, addr string) error {
+	return removeFromRouteTable(prefix, addr)
+}
+
+func getExistingRIBRouteGateway(prefix netip.Prefix) (net.IP, error) {
+	r, err := netroute.New()
+	if err != nil {
+		return nil, err
+	}
+	_, gateway, preferredSrc, err := r.Route(prefix.Addr().AsSlice())
+	if err != nil {
+		log.Errorf("getting routes returned an error: %v", err)
+		return nil, errRouteNotFound
+	}
+
+	if gateway == nil {
+		return preferredSrc, nil
+	}
+
+	return gateway, nil
+}