Merge pull request #14 from tim-beatham/13-netlink-api

Removed interface manipulation via os.Exec into

go.mod

@@ -18,9 +18,11 @@ require (
 	github.com/golang/protobuf v1.5.3 // indirect
 	github.com/google/go-cmp v0.5.9 // indirect
 	github.com/josharian/native v1.1.0 // indirect
+	github.com/jsimonetti/rtnetlink v1.3.5 // indirect
 	github.com/mdlayher/genetlink v1.3.2 // indirect
 	github.com/mdlayher/netlink v1.7.2 // indirect
 	github.com/mdlayher/socket v0.5.0 // indirect
+	github.com/vishvananda/netns v0.0.0-20191106174202-0a2b9b5464df // indirect
 	golang.org/x/crypto v0.13.0 // indirect
 	golang.org/x/net v0.15.0 // indirect
 	golang.org/x/sync v0.3.0 // indirect

pkg/automerge/automerge.go

@@ -207,6 +207,31 @@ func (m *CrdtMeshManager) AddRoutes(nodeId string, routes ...string) error {
 	return nil
 }
 
+// DeleteRoutes deletes the specified routes
+func (m *CrdtMeshManager) RemoveRoutes(nodeId string, routes ...string) error {
+	nodeVal, err := m.doc.Path("nodes").Map().Get(nodeId)
+
+	if err != nil {
+		return err
+	}
+
+	if nodeVal.Kind() != automerge.KindMap {
+		return fmt.Errorf("node is not a map")
+	}
+
+	routeMap, err := nodeVal.Map().Get("routes")
+
+	if err != nil {
+		return err
+	}
+
+	for _, route := range routes {
+		err = routeMap.Map().Delete(route)
+	}
+
+	return err
+}
+
 func (m *CrdtMeshManager) GetSyncer() mesh.MeshSyncer {
 	return NewAutomergeSync(m)
 }

pkg/ctrlserver/ctrlserver.go

@@ -35,7 +35,6 @@ func NewCtrlServer(params *NewCtrlServerParams) (*MeshCtrlServer, error) {
 	ipAllocator := &ip.ULABuilder{}
 	interfaceManipulator := wg.NewWgInterfaceManipulator(params.Client)
 
-	var meshManager mesh.MeshManagerImpl
 	configApplyer := mesh.NewWgMeshConfigApplyer()
 
 	meshManagerParams := &mesh.NewMeshManagerParams{
@@ -49,8 +48,8 @@ func NewCtrlServer(params *NewCtrlServerParams) (*MeshCtrlServer, error) {
 		ConfigApplyer:        configApplyer,
 	}
 
-	configApplyer.SetMeshManager(&meshManager)
 	ctrlServer.MeshManager = mesh.NewMeshManager(meshManagerParams)
+	configApplyer.SetMeshManager(ctrlServer.MeshManager)
 
 	ctrlServer.Conf = params.Conf
 	connManagerParams := conn.NewConnectionManagerParams{
@@ -112,6 +111,10 @@ func (s *MeshCtrlServer) Close() error {
 		logging.Log.WriteErrorf(err.Error())
 	}
 
+	if err := s.MeshManager.Close(); err != nil {
+		logging.Log.WriteErrorf(err.Error())
+	}
+
 	if err := s.ConnectionServer.Close(); err != nil {
 		logging.Log.WriteErrorf(err.Error())
 	}

pkg/lib/rtnetlink.go

@@ -0,0 +1,300 @@
+package lib
+
+import (
+	"encoding/binary"
+	"fmt"
+	"net"
+
+	"github.com/jsimonetti/rtnetlink"
+	logging "github.com/tim-beatham/wgmesh/pkg/log"
+	"golang.org/x/sys/unix"
+)
+
+type RtNetlinkConfig struct {
+	conn *rtnetlink.Conn
+}
+
+func NewRtNetlinkConfig() (*RtNetlinkConfig, error) {
+	conn, err := rtnetlink.Dial(nil)
+
+	if err != nil {
+		return nil, err
+	}
+
+	return &RtNetlinkConfig{conn: conn}, nil
+}
+
+const WIREGUARD_MTU = 1420
+
+// Create a netlink interface if it does not exist. ifName is the name of the netlink interface
+func (c *RtNetlinkConfig) CreateLink(ifName string) error {
+	_, err := net.InterfaceByName(ifName)
+
+	if err == nil {
+		return fmt.Errorf("interface %s already exists", ifName)
+	}
+
+	err = c.conn.Link.New(&rtnetlink.LinkMessage{
+		Family: unix.AF_UNSPEC,
+		Flags:  unix.IFF_UP,
+		Attributes: &rtnetlink.LinkAttributes{
+			Name: ifName,
+			Info: &rtnetlink.LinkInfo{Kind: "wireguard"},
+			MTU:  uint32(WIREGUARD_MTU),
+		},
+	})
+
+	if err != nil {
+		return fmt.Errorf("failed to create wireguard interface: %w", err)
+	}
+
+	return nil
+}
+
+// Delete link delete the specified interface
+func (c *RtNetlinkConfig) DeleteLink(ifName string) error {
+	iface, err := net.InterfaceByName(ifName)
+
+	if err != nil {
+		return fmt.Errorf("failed to get interface %s %w", ifName, err)
+	}
+
+	err = c.conn.Link.Delete(uint32(iface.Index))
+
+	if err != nil {
+		return fmt.Errorf("failed to delete wg interface %w", err)
+	}
+
+	return nil
+}
+
+// AddAddress adds an address to the given interface.
+func (c *RtNetlinkConfig) AddAddress(ifName string, address string) error {
+	iface, err := net.InterfaceByName(ifName)
+
+	if err != nil {
+		return fmt.Errorf("failed to get interface %s error: %w", ifName, err)
+	}
+
+	addr, cidr, err := net.ParseCIDR(address)
+
+	if err != nil {
+		return fmt.Errorf("failed to parse CIDR %s error: %w", addr, err)
+	}
+
+	family := unix.AF_INET6
+
+	ipv4 := cidr.IP.To4()
+
+	if ipv4 != nil {
+		family = unix.AF_INET
+	}
+
+	// Calculate the prefix length
+	ones, _ := cidr.Mask.Size()
+
+	// Calculate the broadcast IP
+	// Only used when family is AF_INET
+	var brd net.IP
+	if ipv4 != nil {
+		brd = make(net.IP, len(ipv4))
+		binary.BigEndian.PutUint32(brd, binary.BigEndian.Uint32(ipv4)|^binary.BigEndian.Uint32(net.IP(cidr.Mask).To4()))
+	}
+
+	err = c.conn.Address.New(&rtnetlink.AddressMessage{
+		Family:       uint8(family),
+		PrefixLength: uint8(ones),
+		Scope:        unix.RT_SCOPE_UNIVERSE,
+		Index:        uint32(iface.Index),
+		Attributes: &rtnetlink.AddressAttributes{
+			Address:   addr,
+			Local:     addr,
+			Broadcast: brd,
+		},
+	})
+
+	if err != nil {
+		err = fmt.Errorf("failed to add address to link %w", err)
+	}
+
+	return err
+}
+
+// AddRoute: adds a route to the routing table.
+// ifName is the intrface to add the route to
+// gateway is the IP of the gateway device to hop to
+// dst is the network prefix of the advertised destination
+func (c *RtNetlinkConfig) AddRoute(ifName string, route Route) error {
+	iface, err := net.InterfaceByName(ifName)
+
+	if err != nil {
+		return fmt.Errorf("failed accessing interface %s error %w", ifName, err)
+	}
+
+	gw := route.Gateway
+	dst := route.Destination
+
+	var family uint8 = unix.AF_INET6
+
+	if dst.IP.To4() != nil {
+		family = unix.AF_INET
+	}
+
+	attr := rtnetlink.RouteAttributes{
+		Dst:      dst.IP,
+		OutIface: uint32(iface.Index),
+		Gateway:  gw,
+	}
+
+	ones, _ := dst.Mask.Size()
+
+	err = c.conn.Route.Replace(&rtnetlink.RouteMessage{
+		Family:     family,
+		Table:      unix.RT_TABLE_MAIN,
+		Protocol:   unix.RTPROT_BOOT,
+		Scope:      unix.RT_SCOPE_LINK,
+		Type:       unix.RTN_UNICAST,
+		DstLength:  uint8(ones),
+		Attributes: attr,
+	})
+
+	if err != nil {
+		return fmt.Errorf("failed to add route %w", err)
+	}
+
+	return nil
+}
+
+// DeleteRoute deletes routes with the gateway and destination
+func (c *RtNetlinkConfig) DeleteRoute(ifName string, route Route) error {
+	iface, err := net.InterfaceByName(ifName)
+
+	if err != nil {
+		return fmt.Errorf("failed accessing interface %s error %w", ifName, err)
+	}
+
+	gw := route.Gateway
+	dst := route.Destination
+
+	var family uint8 = unix.AF_INET6
+
+	if dst.IP.To4() != nil {
+		family = unix.AF_INET
+	}
+
+	attr := rtnetlink.RouteAttributes{
+		Dst:      dst.IP,
+		OutIface: uint32(iface.Index),
+		Gateway:  gw,
+	}
+
+	ones, _ := dst.Mask.Size()
+
+	err = c.conn.Route.Delete(&rtnetlink.RouteMessage{
+		Family:     family,
+		Table:      unix.RT_TABLE_MAIN,
+		Protocol:   unix.RTPROT_BOOT,
+		Scope:      unix.RT_SCOPE_LINK,
+		Type:       unix.RTN_UNICAST,
+		DstLength:  uint8(ones),
+		Attributes: attr,
+	})
+
+	if err != nil {
+		return fmt.Errorf("failed to delete route %w", err)
+	}
+
+	return nil
+}
+
+type Route struct {
+	Gateway     net.IP
+	Destination net.IPNet
+}
+
+func (r1 Route) equal(r2 Route) bool {
+	return r1.Gateway.String() == r2.Gateway.String() &&
+		r1.Destination.String() == r2.Destination.String()
+}
+
+// DeleteRoutes deletes all routes not in exclude
+func (c *RtNetlinkConfig) DeleteRoutes(ifName string, family uint8, exclude ...Route) error {
+	routes := make([]rtnetlink.RouteMessage, 0)
+
+	if len(exclude) != 0 {
+		lRoutes, err := c.listRoutes(ifName, family, exclude[0].Gateway)
+
+		if err != nil {
+			return err
+		}
+
+		routes = lRoutes
+	}
+
+	ifRoutes := make([]Route, 0)
+
+	for _, rtRoute := range routes {
+		logging.Log.WriteInfof("Routes: %s", rtRoute.Attributes.Dst.String())
+		maskSize := 128
+
+		if family == unix.AF_INET {
+			maskSize = 32
+		}
+
+		cidr := net.CIDRMask(int(rtRoute.DstLength), maskSize)
+		route := Route{
+			Gateway:     rtRoute.Attributes.Gateway,
+			Destination: net.IPNet{IP: rtRoute.Attributes.Dst, Mask: cidr},
+		}
+
+		ifRoutes = append(ifRoutes, route)
+	}
+
+	shouldExclude := func(r Route) bool {
+		for _, route := range exclude {
+			if route.equal(r) {
+				return false
+			}
+		}
+		return true
+	}
+
+	toDelete := Filter(ifRoutes, shouldExclude)
+
+	for _, route := range toDelete {
+		logging.Log.WriteInfof("Deleting route %s", route.Destination.String())
+		err := c.DeleteRoute(ifName, route)
+
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+// listRoutes lists all routes on the interface
+func (c *RtNetlinkConfig) listRoutes(ifName string, family uint8, gateway net.IP) ([]rtnetlink.RouteMessage, error) {
+	iface, err := net.InterfaceByName(ifName)
+
+	if err != nil {
+		return nil, fmt.Errorf("failed accessing interface %s error %w", ifName, err)
+	}
+
+	routes, err := c.conn.Route.List()
+
+	if err != nil {
+		return nil, fmt.Errorf("failed to get route %w", err)
+	}
+
+	filterFunc := func(r rtnetlink.RouteMessage) bool {
+		return r.Attributes.Gateway.Equal(gateway) && r.Attributes.OutIface == uint32(iface.Index)
+	}
+
+	routes = Filter(routes, filterFunc)
+	return routes, nil
+}
+
+func (c *RtNetlinkConfig) Close() error {
+	return c.conn.Close()
+}

pkg/mesh/manager.go

@@ -29,6 +29,7 @@ type MeshManager interface {
 	GetClient() *wgctrl.Client
 	GetMeshes() map[string]MeshProvider
 	Prune() error
+	Close() error
 }
 
 type MeshManagerImpl struct {
@@ -77,7 +78,7 @@ func (m *MeshManagerImpl) CreateMesh(devName string, port int) (string, error) {
 	})
 
 	if err != nil {
-		return "", err
+		return "", fmt.Errorf("error creating mesh: %w", err)
 	}
 
 	err = m.interfaceManipulator.CreateInterface(&wg.CreateInterfaceParams{
@@ -86,15 +87,10 @@ func (m *MeshManagerImpl) CreateMesh(devName string, port int) (string, error) {
 	})
 
 	if err != nil {
-		return "", nil
+		return "", fmt.Errorf("error creating mesh: %w", err)
 	}
 
 	m.Meshes[meshId] = nodeManager
-
-	if err != nil {
-		logging.Log.WriteErrorf(err.Error())
-	}
-
 	return meshId, nil
 }
 
@@ -152,25 +148,13 @@ func (s *MeshManagerImpl) EnableInterface(meshId string) error {
 		return err
 	}
 
-	meshNode, err := s.GetSelf(meshId)
+	err = s.RouteManager.InstallRoutes()
 
 	if err != nil {
 		return err
 	}
 
-	mesh := s.GetMesh(meshId)
+	return nil
-
-	if err != nil {
-		return err
-	}
-
-	dev, err := mesh.GetDevice()
-
-	if err != nil {
-		return err
-	}
-
-	return s.interfaceManipulator.EnableInterface(dev.Name, meshNode.GetWgHost().String())
 }
 
 // GetPublicKey: Gets the public key of the WireGuard mesh
@@ -202,6 +186,12 @@ type AddSelfParams struct {
 
 // AddSelf adds this host to the mesh
 func (s *MeshManagerImpl) AddSelf(params *AddSelfParams) error {
+	mesh := s.GetMesh(params.MeshId)
+
+	if mesh == nil {
+		return fmt.Errorf("addself: mesh %s does not exist", params.MeshId)
+	}
+
 	pubKey, err := s.GetPublicKey(params.MeshId)
 
 	if err != nil {
@@ -221,21 +211,45 @@ func (s *MeshManagerImpl) AddSelf(params *AddSelfParams) error {
 		Endpoint:  params.Endpoint,
 	})
 
+	device, err := mesh.GetDevice()
+
+	if err != nil {
+		return fmt.Errorf("failed to get device %w", err)
+	}
+
+	err = s.interfaceManipulator.AddAddress(device.Name, fmt.Sprintf("%s/64", nodeIP))
+
+	if err != nil {
+		return fmt.Errorf("addSelf: failed to add address to dev %w", err)
+	}
+
 	s.Meshes[params.MeshId].AddNode(node)
 	return s.RouteManager.UpdateRoutes()
 }
 
 // LeaveMesh leaves the mesh network
 func (s *MeshManagerImpl) LeaveMesh(meshId string) error {
-	_, exists := s.Meshes[meshId]
+	mesh, exists := s.Meshes[meshId]
 
 	if !exists {
 		return fmt.Errorf("mesh %s does not exist", meshId)
 	}
 
-	// For now just delete the mesh with the ID.
+	err := s.RouteManager.RemoveRoutes(meshId)
+
+	if err != nil {
+		return err
+	}
+
+	device, err := mesh.GetDevice()
+
+	if err != nil {
+		return err
+	}
+
+	err = s.interfaceManipulator.RemoveInterface(device.Name)
 	delete(s.Meshes, meshId)
-	return nil
+	return err
 }
 
 func (s *MeshManagerImpl) GetSelf(meshId string) (MeshNode, error) {
@@ -261,7 +275,13 @@ func (s *MeshManagerImpl) GetSelf(meshId string) (MeshNode, error) {
 }
 
 func (s *MeshManagerImpl) ApplyConfig() error {
-	return s.configApplyer.ApplyConfig()
+	err := s.configApplyer.ApplyConfig()
+
+	if err != nil {
+		return err
+	}
+
+	return s.RouteManager.InstallRoutes()
 }
 
 func (s *MeshManagerImpl) SetDescription(description string) error {
@@ -307,6 +327,24 @@ func (s *MeshManagerImpl) GetMeshes() map[string]MeshProvider {
 	return s.Meshes
 }
 
+func (s *MeshManagerImpl) Close() error {
+	for _, mesh := range s.Meshes {
+		dev, err := mesh.GetDevice()
+
+		if err != nil {
+			return err
+		}
+
+		err = s.interfaceManipulator.RemoveInterface(dev.Name)
+
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
 // NewMeshManagerParams params required to create an instance of a mesh manager
 type NewMeshManagerParams struct {
 	Conf                 conf.WgMeshConfiguration
@@ -317,6 +355,7 @@ type NewMeshManagerParams struct {
 	IPAllocator          ip.IPAllocator
 	InterfaceManipulator wg.WgInterfaceManipulator
 	ConfigApplyer        MeshConfigApplyer
+	RouteManager         RouteManager
 }
 
 // Creates a new instance of a mesh manager with the given parameters
@@ -342,7 +381,12 @@ func NewMeshManager(params *NewMeshManagerParams) *MeshManagerImpl {
 	}
 
 	m.configApplyer = params.ConfigApplyer
-	m.RouteManager = NewRouteManager(m)
+	m.RouteManager = params.RouteManager
+
+	if m.RouteManager == nil {
+		m.RouteManager = NewRouteManager(m)
+	}
+
 	m.idGenerator = params.IdGenerator
 	m.ipAllocator = params.IPAllocator
 	m.interfaceManipulator = params.InterfaceManipulator

pkg/mesh/manager_test.go

@@ -32,6 +32,7 @@ func getMeshManager() *MeshManagerImpl {
 		IPAllocator:          &ip.ULABuilder{},
 		InterfaceManipulator: &wg.WgInterfaceManipulatorStub{},
 		ConfigApplyer:        &MeshConfigApplyerStub{},
+		RouteManager:         &RouteManagerStub{},
 	})
 
 	return manager
@@ -186,7 +187,7 @@ func TestLeaveMeshDeletesMesh(t *testing.T) {
 	err = manager.LeaveMesh(meshId)
 
 	if err != nil {
-		t.Error(err)
+		t.Fatalf("%s", err.Error())
 	}
 
 	_, exists := manager.Meshes[meshId]

pkg/mesh/route.go

@@ -1,13 +1,20 @@
 package mesh
 
 import (
+	"fmt"
+	"net"
+
 	"github.com/tim-beatham/wgmesh/pkg/ip"
+	"github.com/tim-beatham/wgmesh/pkg/lib"
 	logging "github.com/tim-beatham/wgmesh/pkg/log"
 	"github.com/tim-beatham/wgmesh/pkg/route"
+	"golang.org/x/sys/unix"
 )
 
 type RouteManager interface {
 	UpdateRoutes() error
+	InstallRoutes() error
+	RemoveRoutes(meshId string) error
 }
 
 type RouteManagerImpl struct {
@@ -49,6 +56,129 @@ func (r *RouteManagerImpl) UpdateRoutes() error {
 	return nil
 }
 
+// removeRoutes: removes all meshes we are no longer a part of
+func (r *RouteManagerImpl) RemoveRoutes(meshId string) error {
+	ulaBuilder := new(ip.ULABuilder)
+	meshes := r.meshManager.GetMeshes()
+
+	ipNet, err := ulaBuilder.GetIPNet(meshId)
+
+	if err != nil {
+		return err
+	}
+
+	for _, mesh1 := range meshes {
+		self, err := r.meshManager.GetSelf(meshId)
+
+		if err != nil {
+			return err
+		}
+
+		mesh1.RemoveRoutes(self.GetHostEndpoint(), ipNet.String())
+	}
+	return nil
+}
+
+// AddRoute adds a route to the given interface
+func (m *RouteManagerImpl) addRoute(ifName string, meshPrefix string, routes ...lib.Route) error {
+	rtnl, err := lib.NewRtNetlinkConfig()
+
+	if err != nil {
+		return fmt.Errorf("failed to create config: %w", err)
+	}
+	defer rtnl.Close()
+
+	// Delete any routes that may be vacant
+	err = rtnl.DeleteRoutes(ifName, unix.AF_INET6, routes...)
+
+	if err != nil {
+		return err
+	}
+
+	for _, route := range routes {
+		if route.Destination.String() == meshPrefix {
+			continue
+		}
+
+		err = rtnl.AddRoute(ifName, route)
+
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (m *RouteManagerImpl) installRoute(ifName string, meshid string, node MeshNode) error {
+	routeMapFunc := func(route string) lib.Route {
+		_, cidr, _ := net.ParseCIDR(route)
+
+		r := lib.Route{
+			Destination: *cidr,
+			Gateway:     node.GetWgHost().IP,
+		}
+		return r
+	}
+
+	ipBuilder := &ip.ULABuilder{}
+	ipNet, err := ipBuilder.GetIPNet(meshid)
+
+	if err != nil {
+		return err
+	}
+
+	routes := lib.Map(append(node.GetRoutes(), ipNet.String()), routeMapFunc)
+	return m.addRoute(ifName, ipNet.String(), routes...)
+}
+
+func (m *RouteManagerImpl) installRoutes(meshProvider MeshProvider) error {
+	mesh, err := meshProvider.GetMesh()
+
+	if err != nil {
+		return err
+	}
+
+	dev, err := meshProvider.GetDevice()
+
+	if err != nil {
+		return err
+	}
+
+	self, err := m.meshManager.GetSelf(meshProvider.GetMeshId())
+
+	if err != nil {
+		return err
+	}
+
+	for _, node := range mesh.GetNodes() {
+		if self.GetHostEndpoint() == node.GetHostEndpoint() {
+			continue
+		}
+
+		err = m.installRoute(dev.Name, meshProvider.GetMeshId(), node)
+
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+// InstallRoutes installs all routes to the RIB
+func (r *RouteManagerImpl) InstallRoutes() error {
+	for _, mesh := range r.meshManager.GetMeshes() {
+		err := r.installRoutes(mesh)
+
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
 func NewRouteManager(m MeshManager) RouteManager {
 	return &RouteManagerImpl{meshManager: m, routeInstaller: route.NewRouteInstaller()}
 }

pkg/mesh/route_stub.go

@@ -0,0 +1,16 @@
+package mesh
+
+type RouteManagerStub struct {
+}
+
+func (r *RouteManagerStub) UpdateRoutes() error {
+	return nil
+}
+
+func (r *RouteManagerStub) InstallRoutes() error {
+	return nil
+}
+
+func (r *RouteManagerStub) RemoveRoutes(meshId string) error {
+	return nil
+}

pkg/mesh/stub_types.go

@@ -66,6 +66,11 @@ type MeshProviderStub struct {
 	snapshot *MeshSnapshotStub
 }
 
+// RemoveRoutes implements MeshProvider.
+func (*MeshProviderStub) RemoveRoutes(nodeId string, route ...string) error {
+	panic("unimplemented")
+}
+
 // Prune implements MeshProvider.
 func (*MeshProviderStub) Prune(pruneAmount int) error {
 	return nil
@@ -166,6 +171,11 @@ type MeshManagerStub struct {
 	meshes map[string]MeshProvider
 }
 
+// Close implements MeshManager.
+func (*MeshManagerStub) Close() error {
+	panic("unimplemented")
+}
+
 // Prune implements MeshManager.
 func (*MeshManagerStub) Prune() error {
 	return nil

pkg/mesh/types.go

@@ -64,6 +64,8 @@ type MeshProvider interface {
 	UpdateTimeStamp(nodeId string) error
 	// AddRoutes: adds routes to the given node
 	AddRoutes(nodeId string, route ...string) error
+	// DeleteRoutes: deletes the routes from the node
+	RemoveRoutes(nodeId string, route ...string) error
 	// GetSyncer: returns the automerge syncer for sync
 	GetSyncer() MeshSyncer
 	// SetDescription: sets the description of this automerge data type

pkg/robin/requester.go

@@ -30,6 +30,10 @@ func (n *IpcHandler) CreateMesh(args *ipc.NewMeshArgs, reply *string) error {
 		Endpoint: args.Endpoint,
 	})
 
+	if err != nil {
+		return err
+	}
+
 	*reply = meshId
 	return err
 }
@@ -122,6 +126,7 @@ func (n *IpcHandler) GetMesh(meshId string, reply *ipc.GetMeshReply) error {
 	if mesh == nil {
 		return errors.New("mesh does not exist")
 	}
+
 	nodes := make([]ctrlserver.MeshNode, len(meshSnapshot.GetNodes()))
 
 	i := 0

pkg/sync/syncer.go

@@ -31,7 +31,11 @@ type SyncerImpl struct {
 // Sync: Sync random nodes
 func (s *SyncerImpl) Sync(meshId string) error {
 	logging.Log.WriteInfof("UPDATING WG CONF")
-	s.manager.ApplyConfig()
+	err := s.manager.ApplyConfig()
+
+	if err != nil {
+		logging.Log.WriteInfof("Failed to update config %w", err)
+	}
 
 	if !s.manager.HasChanges(meshId) && s.infectionCount == 0 {
 		logging.Log.WriteInfof("No changes for %s", meshId)

pkg/wg/stubs.go

@@ -6,6 +6,10 @@ func (i *WgInterfaceManipulatorStub) CreateInterface(params *CreateInterfacePara
 	return nil
 }
 
-func (i *WgInterfaceManipulatorStub) EnableInterface(ifName string, ip string) error {
+func (i *WgInterfaceManipulatorStub) AddAddress(ifName string, addr string) error {
+	return nil
+}
+
+func (i *WgInterfaceManipulatorStub) RemoveInterface(ifName string) error {
 	return nil
 }

pkg/wg/types.go

@@ -16,7 +16,8 @@ type CreateInterfaceParams struct {
 type WgInterfaceManipulator interface {
 	// CreateInterface creates a WireGuard interface
 	CreateInterface(params *CreateInterfaceParams) error
-	// Enable interface enables the given interface with
+	// AddAddress adds an address to the given interface name
-	// the IP. It overrides the IP at the interface
+	AddAddress(ifName string, addr string) error
-	EnableInterface(ifName string, ip string) error
+	// RemoveInterface removes the specified interface
+	RemoveInterface(ifName string) error
 }

pkg/wg/wg.go

@@ -1,50 +1,37 @@
 package wg
 
 import (
-	"errors"
 	"fmt"
-	"net"
-	"os/exec"
 
+	"github.com/tim-beatham/wgmesh/pkg/lib"
 	logging "github.com/tim-beatham/wgmesh/pkg/log"
 	"golang.zx2c4.com/wireguard/wgctrl"
 	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
 )
 
-// createInterface uses ip link to create an interface. If the interface exists
-// it returns an error
-func createInterface(ifName string) error {
-	_, err := net.InterfaceByName(ifName)
-
-	if err == nil {
-		err = flushInterface(ifName)
-		return err
-	}
-
-	// Check if the interface exists
-	cmd := exec.Command("/usr/bin/ip", "link", "add", "dev", ifName, "type", "wireguard")
-
-	if err := cmd.Run(); err != nil {
-		return err
-	}
-	return nil
-}
-
 type WgInterfaceManipulatorImpl struct {
 	client *wgctrl.Client
 }
 
+// CreateInterface creates a WireGuard interface
 func (m *WgInterfaceManipulatorImpl) CreateInterface(params *CreateInterfaceParams) error {
-	err := createInterface(params.IfName)
+	rtnl, err := lib.NewRtNetlinkConfig()
 
 	if err != nil {
-		return err
+		return fmt.Errorf("failed to access link: %w", err)
+	}
+	defer rtnl.Close()
+
+	err = rtnl.CreateLink(params.IfName)
+
+	if err != nil {
+		return fmt.Errorf("failed to create link: %w", err)
 	}
 
 	privateKey, err := wgtypes.GeneratePrivateKey()
 
 	if err != nil {
-		return err
+		return fmt.Errorf("failed to create private key: %w", err)
 	}
 
 	var cfg wgtypes.Config = wgtypes.Config{
@@ -52,59 +39,44 @@ func (m *WgInterfaceManipulatorImpl) CreateInterface(params *CreateInterfacePara
 		ListenPort: &params.Port,
 	}
 
-	m.client.ConfigureDevice(params.IfName, cfg)
+	err = m.client.ConfigureDevice(params.IfName, cfg)
+
+	if err != nil {
+		return fmt.Errorf("failed to configure dev: %w", err)
+	}
+
+	logging.Log.WriteInfof("ip link set up dev %s type wireguard", params.IfName)
 	return nil
 }
 
-// flushInterface flushes the specified interface
+// Add an address to the given interface
-func flushInterface(ifName string) error {
+func (m *WgInterfaceManipulatorImpl) AddAddress(ifName string, addr string) error {
-	_, err := net.InterfaceByName(ifName)
+	rtnl, err := lib.NewRtNetlinkConfig()
 
 	if err != nil {
-		return &WgError{msg: fmt.Sprintf("Interface %s does not exist cannot flush", ifName)}
+		return fmt.Errorf("failed to create config: %w", err)
+	}
+	defer rtnl.Close()
+
+	err = rtnl.AddAddress(ifName, addr)
+
+	if err != nil {
+		err = fmt.Errorf("failed to add address: %w", err)
 	}
 
-	cmd := exec.Command("/usr/bin/ip", "addr", "flush", "dev", ifName)
+	return err
-
-	if err := cmd.Run(); err != nil {
-		logging.Log.WriteErrorf(fmt.Sprintf("%s error flushing interface %s", err.Error(), ifName))
-		return &WgError{msg: fmt.Sprintf("Failed to flush interface %s", ifName)}
-	}
-
-	return nil
 }
 
-// EnableInterface flushes the interface and sets the ip address of the
+// RemoveInterface implements WgInterfaceManipulator.
-// interface
+func (*WgInterfaceManipulatorImpl) RemoveInterface(ifName string) error {
-func (m *WgInterfaceManipulatorImpl) EnableInterface(ifName string, ip string) error {
+	rtnl, err := lib.NewRtNetlinkConfig()
-	if len(ifName) == 0 {
-		return errors.New("ifName not provided")
-	}
-
-	err := flushInterface(ifName)
 
 	if err != nil {
-		return err
+		return fmt.Errorf("failed to create config: %w", err)
 	}
+	defer rtnl.Close()
 
-	cmd := exec.Command("/usr/bin/ip", "link", "set", "up", "dev", ifName)
+	return rtnl.DeleteLink(ifName)
-
-	if err := cmd.Run(); err != nil {
-		return err
-	}
-
-	hostIp, _, err := net.ParseCIDR(ip)
-
-	if err != nil {
-		return err
-	}
-
-	cmd = exec.Command("/usr/bin/ip", "addr", "add", hostIp.String()+"/64", "dev", ifName)
-
-	if err := cmd.Run(); err != nil {
-		return err
-	}
-	return nil
 }
 
 func NewWgInterfaceManipulator(client *wgctrl.Client) WgInterfaceManipulator {