wip routes

internal/adapters/wireguard.go

@@ -299,38 +299,106 @@ func (r *WgRepo) updateWireGuardInterface(pi *domain.PhysicalInterface) error {
 	return nil
 }
 
-func (r *WgRepo) SaveRoutes(_ context.Context, interfaceId domain.InterfaceIdentifier, table int, allowedIPs []domain.Cidr) error {
-	if table == -1 {
-		logrus.Trace("ignoring route update")
+func (r *WgRepo) SaveRoutes(_ context.Context, iface *domain.Interface, peers []domain.Peer) error {
+	table := iface.GetRoutingTable()
+	if table == -2 {
+		logrus.Trace("ignoring route update, feature disabled")
 		return nil
 	}
 
-	link, err := r.nl.LinkByName(string(interfaceId))
+	if !iface.IsDisabled() {
+		return r.setupRoutes(iface, peers)
+	} else {
+		return r.cleanupRoutes(iface, peers)
+	}
+}
+
+func (r *WgRepo) setupRoutes(iface *domain.Interface, peers []domain.Peer) error {
+	link, err := r.nl.LinkByName(string(iface.Identifier))
 	if err != nil {
-		return err
+		return fmt.Errorf("unable to find physical interface %s: %w", iface.Identifier, err)
 	}
 
 	if link.Attrs().OperState == netlink.OperDown {
 		return nil // cannot set route for interface that is down
 	}
 
+	table, fwmark, err := r.getRoutingTableAndFwMark(iface, peers, link)
+	if err != nil {
+		return fmt.Errorf("failed to get table and fwmark: %w", err)
+	}
+
 	// try to mimic wg-quick (https://git.zx2c4.com/wireguard-tools/tree/src/wg-quick/linux.bash)
+	allowedIPs := iface.GetAllowedIPs(peers)
 	for _, allowedIP := range allowedIPs {
-		// if allowedIP.Prefix().Bits() == 0 { // default route handling - TODO
-		err := r.nl.RouteReplace(&netlink.Route{
-			LinkIndex: link.Attrs().Index,
-			Dst:       allowedIP.IpNet(),
-			Table:     table,
-			Scope:     unix.RT_SCOPE_LINK,
-			Type:      unix.RTN_UNICAST,
-		})
-		if err != nil {
-			return fmt.Errorf("failed to add/update route %s: %w", allowedIP.String(), err)
+		if allowedIP.Prefix().Bits() == 0 { // default route handling
+			if err := r.nl.RouteReplace(&netlink.Route{
+				LinkIndex: link.Attrs().Index,
+				Dst:       allowedIP.IpNet(),
+				Table:     table,
+				Scope:     unix.RT_SCOPE_LINK,
+				Type:      unix.RTN_UNICAST,
+			}); err != nil {
+				return fmt.Errorf("failed to add/update route %s: %w", allowedIP.String(), err)
+			}
+
+			family := netlink.FAMILY_V4
+			if !allowedIP.IsV4() {
+				family = netlink.FAMILY_V6
+			}
+			if err := r.nl.RuleAdd(&netlink.Rule{
+				Family:            family,
+				Table:             table,
+				Mark:              fwmark,
+				Invert:            true,
+				SuppressIfgroup:   -1,
+				SuppressPrefixlen: -1,
+				Priority:          -1,
+				Mask:              -1,
+				Goto:              -1,
+				Flow:              -1,
+			}); err != nil {
+				return fmt.Errorf("failed to setup rule for fwmark %d: %w", fwmark, err)
+			}
+			if err := r.nl.RuleAdd(&netlink.Rule{
+				Family:            family,
+				Table:             unix.RT_TABLE_MAIN,
+				SuppressIfgroup:   -1,
+				SuppressPrefixlen: 0,
+				Priority:          -1,
+				Mark:              -1,
+				Mask:              -1,
+				Goto:              -1,
+				Flow:              -1,
+			}); err != nil {
+				return fmt.Errorf("failed to setup rule for main table: %w", err)
+			}
+		} else {
+			err := r.nl.RouteReplace(&netlink.Route{
+				LinkIndex: link.Attrs().Index,
+				Dst:       allowedIP.IpNet(),
+				Table:     table,
+				Scope:     unix.RT_SCOPE_LINK,
+				Type:      unix.RTN_UNICAST,
+			})
+			if err != nil {
+				return fmt.Errorf("failed to add/update route %s: %w", allowedIP.String(), err)
+			}
 		}
 	}
 
-	// Remove unwanted routes
-	rawRoutes, err := r.nl.RouteListFiltered(netlink.FAMILY_ALL, &netlink.Route{
+	if err := r.removeDeprecatedRoutes(link, allowedIPs, netlink.FAMILY_V4); err != nil {
+		return fmt.Errorf("failed to remove deprecated v4 routes: %w", err)
+	}
+	if err := r.removeDeprecatedRoutes(link, allowedIPs, netlink.FAMILY_V6); err != nil {
+		return fmt.Errorf("failed to remove deprecated v6 routes: %w", err)
+	}
+
+	return nil
+}
+
+func (r *WgRepo) removeDeprecatedRoutes(link netlink.Link, allowedIPs []domain.Cidr, family int) error {
+	rawRoutes, err := r.nl.RouteListFiltered(family, &netlink.Route{
 		LinkIndex: link.Attrs().Index,
 		Table:     unix.RT_TABLE_UNSPEC, // all tables
 		Scope:     unix.RT_SCOPE_LINK,
@@ -340,7 +408,16 @@ func (r *WgRepo) SaveRoutes(_ context.Context, interfaceId domain.InterfaceIdent
 		return fmt.Errorf("failed to fetch raw routes: %w", err)
 	}
 	for _, rawRoute := range rawRoutes {
-		netlinkAddr := domain.CidrFromIpNet(*rawRoute.Dst)
+		var netlinkAddr domain.Cidr
+		if rawRoute.Dst == nil {
+			if family == netlink.FAMILY_V4 {
+				netlinkAddr, _ = domain.CidrFromString("0.0.0.0/0")
+			} else {
+				netlinkAddr, _ = domain.CidrFromString("::/0")
+			}
+		} else {
+			netlinkAddr = domain.CidrFromIpNet(*rawRoute.Dst)
+		}
 		remove := true
 		for _, allowedIP := range allowedIPs {
 			if netlinkAddr == allowedIP {
@@ -358,10 +435,66 @@ func (r *WgRepo) SaveRoutes(_ context.Context, interfaceId domain.InterfaceIdent
 			return fmt.Errorf("failed to remove deprecated route %s: %w", netlinkAddr.String(), err)
 		}
 	}
+	return nil
+}
+
+func (r *WgRepo) cleanupRoutes(iface *domain.Interface, peers []domain.Peer) error {
+	link, err := r.nl.LinkByName(string(iface.Identifier))
+	if err != nil {
+		return fmt.Errorf("unable to find physical interface %s: %w", iface.Identifier, err)
+	}
+
+	table, _, err := r.getRoutingTableAndFwMark(iface, peers, link)
+	if err != nil {
+		return fmt.Errorf("failed to get table and fwmark: %w", err)
+	}
+
+	if table == 0 {
+		return nil // noting to remove
+	}
+
+	delRule := netlink.NewRule()
+	delRule.Family = netlink.FAMILY_ALL
+	delRule.Table = table
+	if err := r.nl.RuleDel(delRule); err != nil && !errors.Is(err, unix.ENOENT) {
+		return fmt.Errorf("failed to delete rule for table %d: %w", table, err)
+	}
 
 	return nil
 }
 
+func (r *WgRepo) getRoutingTableAndFwMark(iface *domain.Interface, peers []domain.Peer, link netlink.Link) (table, fwmark int, err error) {
+	allowedIPs := iface.GetAllowedIPs(peers)
+	containsDefaultRoute := false
+	for _, allowedIP := range allowedIPs {
+		if allowedIP.Prefix().Bits() == 0 {
+			containsDefaultRoute = true
+			break
+		}
+	}
+
+	table = iface.GetRoutingTable()
+	fwmark = int(iface.FirewallMark)
+
+	if containsDefaultRoute && table <= 0 {
+		table = 20000 + link.Attrs().Index // generate a new routing table base on interface index
+		logrus.Debugf("using routing table %d to handle default routes", table)
+	}
+	if containsDefaultRoute && fwmark == 0 {
+		fwmark = 20000 + link.Attrs().Index // generate a new (temporary) firewall mark based on the interface index
+		logrus.Debugf("using fwmark %d to handle default routes", table)
+
+		// apply the fwmark
+		err = r.wg.ConfigureDevice(string(iface.Identifier), wgtypes.Config{
+			FirewallMark: &fwmark,
+		})
+		if err != nil {
+			return 0, 0, fmt.Errorf("failed to update temporary fwmark to: %d: %w", fwmark, err)
+		}
+	}
+	return
+}
+
 func (r *WgRepo) DeleteInterface(_ context.Context, id domain.InterfaceIdentifier) error {
 	if err := r.deleteLowLevelInterface(id); err != nil {
 		return err

internal/app/wireguard/repos.go

@@ -41,7 +41,7 @@ type InterfaceController interface {
 	DeleteInterface(_ context.Context, id domain.InterfaceIdentifier) error
 	SavePeer(_ context.Context, deviceId domain.InterfaceIdentifier, id domain.PeerIdentifier, updateFunc func(pp *domain.PhysicalPeer) (*domain.PhysicalPeer, error)) error
 	DeletePeer(_ context.Context, deviceId domain.InterfaceIdentifier, id domain.PeerIdentifier) error
-	SaveRoutes(_ context.Context, deviceId domain.InterfaceIdentifier, table int, allowedIPs []domain.Cidr) error
+	SaveRoutes(_ context.Context, iface *domain.Interface, peers []domain.Peer) error
 }
 
 type WgQuickController interface {

internal/app/wireguard/wireguard_interfaces.go

@@ -384,7 +384,7 @@ func (m Manager) saveInterface(ctx context.Context, iface *domain.Interface, pee
 		return nil, fmt.Errorf("failed to save interface: %w", err)
 	}
 
-	err = m.wg.SaveRoutes(ctx, iface.Identifier, iface.GetRoutingTable(), iface.GetAllowedIPs(peers))
+	err = m.wg.SaveRoutes(ctx, iface, peers)
 	if err != nil {
 		return nil, fmt.Errorf("failed to save routes: %w", err)
 	}

internal/app/wireguard/wireguard_peers.go

@@ -284,7 +284,7 @@ func (m Manager) savePeers(ctx context.Context, peers ...*domain.Peer) error {
 		if err != nil {
 			return fmt.Errorf("failed to load peer interface %s: %w", ifaceId, err)
 		}
-		err = m.wg.SaveRoutes(ctx, iface.Identifier, iface.GetRoutingTable(), iface.GetAllowedIPs(ifacePeers))
+		err = m.wg.SaveRoutes(ctx, iface, ifacePeers)
 		if err != nil {
 			return fmt.Errorf("failed to update peer routes on interface %s: %w", ifaceId, err)
 		}

internal/domain/interface.go

@@ -114,12 +114,17 @@ func (i *Interface) GetAllowedIPs(peers []Peer) []Cidr {
 	return allowedCidrs
 }
 
-// GetRoutingTable returns the routing table number or -1 if an error occurred or RoutingTable was set to "off"
+// GetRoutingTable returns the routing table number or
+//
+//	-1 if an error occurred
+//	-2 if RoutingTable was set to "off"
 func (i *Interface) GetRoutingTable() int {
 	routingTableStr := strings.ToLower(i.RoutingTable)
 	switch {
 	case routingTableStr == "":
 		return 0
+	case routingTableStr == "off":
+		return -2
 	case strings.HasPrefix(routingTableStr, "0x"):
 		numberStr := strings.ReplaceAll(routingTableStr, "0x", "")
 		routingTable, err := strconv.ParseUint(numberStr, 16, 64)