Merge pull request #20 from tim-beatham/19-hash-wg-interface

Hashing the WireGuard interface

cmd/wg-mesh/main.go

@@ -16,7 +16,6 @@ const SockAddr = "/tmp/wgmesh_ipc.sock"
 
 type CreateMeshParams struct {
 	Client   *ipcRpc.Client
-	IfName   string
 	WgPort   int
 	Endpoint string
 }
@@ -24,7 +23,6 @@ type CreateMeshParams struct {
 func createMesh(args *CreateMeshParams) string {
 	var reply string
 	newMeshParams := ipc.NewMeshArgs{
-		IfName:   args.IfName,
 		WgPort:   args.WgPort,
 		Endpoint: args.Endpoint,
 	}
@@ -68,7 +66,6 @@ func joinMesh(params *JoinMeshParams) string {
 	args := ipc.JoinMeshArgs{
 		MeshId:   params.MeshId,
 		IpAdress: params.IpAddress,
-		IfName:   params.IfName,
 		Port:     params.WgPort,
 	}
 
@@ -251,14 +248,12 @@ func main() {
 	deleteServiceCmd := parser.NewCommand("delete-service", "Remove a service from your advertisements")
 	getNodeCmd := parser.NewCommand("get-node", "Get a specific node from the mesh")
 
-	var newMeshIfName *string = newMeshCmd.String("f", "ifname", &argparse.Options{Required: true})
+	var newMeshPort *int = newMeshCmd.Int("p", "wgport", &argparse.Options{})
-	var newMeshPort *int = newMeshCmd.Int("p", "wgport", &argparse.Options{Required: true})
 	var newMeshEndpoint *string = newMeshCmd.String("e", "endpoint", &argparse.Options{})
 
 	var joinMeshId *string = joinMeshCmd.String("m", "mesh", &argparse.Options{Required: true})
 	var joinMeshIpAddress *string = joinMeshCmd.String("i", "ip", &argparse.Options{Required: true})
-	var joinMeshIfName *string = joinMeshCmd.String("f", "ifname", &argparse.Options{Required: true})
+	var joinMeshPort *int = joinMeshCmd.Int("p", "wgport", &argparse.Options{})
-	var joinMeshPort *int = joinMeshCmd.Int("p", "wgport", &argparse.Options{Required: true})
 	var joinMeshEndpoint *string = joinMeshCmd.String("e", "endpoint", &argparse.Options{})
 
 	var enableInterfaceMeshId *string = enableInterfaceCmd.String("m", "mesh", &argparse.Options{Required: true})
@@ -298,7 +293,6 @@ func main() {
 	if newMeshCmd.Happened() {
 		fmt.Println(createMesh(&CreateMeshParams{
 			Client:   client,
-			IfName:   *newMeshIfName,
 			WgPort:   *newMeshPort,
 			Endpoint: *newMeshEndpoint,
 		}))
@@ -311,7 +305,6 @@ func main() {
 	if joinMeshCmd.Happened() {
 		fmt.Println(joinMesh(&JoinMeshParams{
 			Client:    client,
-			IfName:    *joinMeshIfName,
 			WgPort:    *joinMeshPort,
 			IpAddress: *joinMeshIpAddress,
 			MeshId:    *joinMeshId,

pkg/api/apiserver.go

@@ -62,11 +62,11 @@ func (s *SmegServer) CreateMesh(c *gin.Context) {
 		c.JSON(http.StatusBadRequest, &gin.H{
 			"error": err.Error(),
 		})
+
 		return
 	}
 
 	ipcRequest := ipc.NewMeshArgs{
-		IfName: createMesh.IfName,
 		WgPort: createMesh.WgPort,
 	}
 
@@ -100,7 +100,6 @@ func (s *SmegServer) JoinMesh(c *gin.Context) {
 	ipcRequest := ipc.JoinMeshArgs{
 		MeshId:   joinMesh.MeshId,
 		IpAdress: joinMesh.Bootstrap,
-		IfName:   joinMesh.IfName,
 		Port:     joinMesh.WgPort,
 	}
 

pkg/api/types.go

@@ -18,13 +18,11 @@ type SmegMesh struct {
 }
 
 type CreateMeshRequest struct {
-	IfName string `json:"ifName" binding:"required"`
+	WgPort int `json:"port" binding:"gte=1024,lt=65535"`
-	WgPort int    `json:"port" binding:"required,gte=1024,lt=65535"`
 }
 
 type JoinMeshRequest struct {
-	IfName    string `json:"ifName" binding:"required"`
+	WgPort    int    `json:"port" binding:"gte=1024,lt=65535"`
-	WgPort    int    `json:"port" binding:"required,gte=1024,lt=65535"`
 	Bootstrap string `json:"bootstrap" binding:"required"`
 	MeshId    string `json:"meshid" binding:"required"`
 }

pkg/ipc/ipc.go

@@ -11,8 +11,6 @@ import (
 )
 
 type NewMeshArgs struct {
-	// IfName is the interface that the mesh instance will run on
-	IfName string
 	// WgPort is the WireGuard port to expose
 	WgPort int
 	// Endpoint is the routable alias of the machine. Can be an IP
@@ -25,8 +23,6 @@ type JoinMeshArgs struct {
 	MeshId string
 	// IpAddress is a routable IP in another mesh
 	IpAdress string
-	// IfName is the interface name of the mesh
-	IfName string
 	// Port is the WireGuard port to expose
 	Port int
 	// Endpoint is the routable address of this machine. If not provided

pkg/mesh/manager.go

@@ -14,7 +14,7 @@ import (
 )
 
 type MeshManager interface {
-	CreateMesh(devName string, port int) (string, error)
+	CreateMesh(port int) (string, error)
 	AddMesh(params *AddMeshParams) error
 	HasChanges(meshid string) bool
 	GetMesh(meshId string) MeshProvider
@@ -115,15 +115,25 @@ func (m *MeshManagerImpl) Prune() error {
 }
 
 // CreateMesh: Creates a new mesh, stores it and returns the mesh id
-func (m *MeshManagerImpl) CreateMesh(devName string, port int) (string, error) {
+func (m *MeshManagerImpl) CreateMesh(port int) (string, error) {
 	meshId, err := m.idGenerator.GetId()
 
+	var ifName string = ""
+
 	if err != nil {
 		return "", err
 	}
 
+	if !m.conf.StubWg {
+		ifName, err = m.interfaceManipulator.CreateInterface(port)
+
+		if err != nil {
+			return "", fmt.Errorf("error creating mesh: %w", err)
+		}
+	}
+
 	nodeManager, err := m.meshProviderFactory.CreateMesh(&MeshProviderFactoryParams{
-		DevName: devName,
+		DevName: ifName,
 		Port:    port,
 		Conf:    m.conf,
 		Client:  m.Client,
@@ -134,32 +144,31 @@ func (m *MeshManagerImpl) CreateMesh(devName string, port int) (string, error) {
 		return "", fmt.Errorf("error creating mesh: %w", err)
 	}
 
-	if !m.conf.StubWg {
-		err = m.interfaceManipulator.CreateInterface(&wg.CreateInterfaceParams{
-			IfName: devName,
-			Port:   port,
-		})
-
-		if err != nil {
-			return "", fmt.Errorf("error creating mesh: %w", err)
-		}
-	}
-
 	m.Meshes[meshId] = nodeManager
 	return meshId, nil
 }
 
 type AddMeshParams struct {
 	MeshId    string
-	DevName   string
 	WgPort    int
 	MeshBytes []byte
 }
 
 // AddMesh: Add the mesh to the list of meshes
 func (m *MeshManagerImpl) AddMesh(params *AddMeshParams) error {
+	var ifName string
+	var err error
+
+	if !m.conf.StubWg {
+		ifName, err = m.interfaceManipulator.CreateInterface(params.WgPort)
+
+		if err != nil {
+			return err
+		}
+	}
+
 	meshProvider, err := m.meshProviderFactory.CreateMesh(&MeshProviderFactoryParams{
-		DevName: params.DevName,
+		DevName: ifName,
 		Port:    params.WgPort,
 		Conf:    m.conf,
 		Client:  m.Client,
@@ -177,14 +186,6 @@ func (m *MeshManagerImpl) AddMesh(params *AddMeshParams) error {
 	}
 
 	m.Meshes[params.MeshId] = meshProvider
-
-	if !m.conf.StubWg {
-		return m.interfaceManipulator.CreateInterface(&wg.CreateInterfaceParams{
-			IfName: params.DevName,
-			Port:   params.WgPort,
-		})
-	}
-
 	return nil
 }
 

pkg/mesh/stub_types.go

@@ -250,7 +250,7 @@ func NewMeshManagerStub() MeshManager {
 	return &MeshManagerStub{meshes: make(map[string]MeshProvider)}
 }
 
-func (m *MeshManagerStub) CreateMesh(devName string, port int) (string, error) {
+func (m *MeshManagerStub) CreateMesh(port int) (string, error) {
 	return "tim123", nil
 }
 

pkg/robin/requester.go

@@ -20,7 +20,7 @@ type IpcHandler struct {
 }
 
 func (n *IpcHandler) CreateMesh(args *ipc.NewMeshArgs, reply *string) error {
-	meshId, err := n.Server.GetMeshManager().CreateMesh(args.IfName, args.WgPort)
+	meshId, err := n.Server.GetMeshManager().CreateMesh(args.WgPort)
 
 	if err != nil {
 		return err
@@ -83,7 +83,6 @@ func (n *IpcHandler) JoinMesh(args ipc.JoinMeshArgs, reply *string) error {
 
 	err = n.Server.GetMeshManager().AddMesh(&mesh.AddMeshParams{
 		MeshId:    args.MeshId,
-		DevName:   args.IfName,
 		WgPort:    args.Port,
 		MeshBytes: meshReply.Mesh,
 	})

pkg/sync/syncrequester.go

@@ -50,7 +50,6 @@ func (s *SyncRequesterImpl) GetMesh(meshId string, ifName string, port int, endP
 
 	err = s.server.MeshManager.AddMesh(&mesh.AddMeshParams{
 		MeshId:    meshId,
-		DevName:   ifName,
 		WgPort:    port,
 		MeshBytes: reply.Mesh,
 	})

pkg/wg/stubs.go

@@ -2,7 +2,7 @@ package wg
 
 type WgInterfaceManipulatorStub struct{}
 
-func (i *WgInterfaceManipulatorStub) CreateInterface(params *CreateInterfaceParams) error {
+func (i *WgInterfaceManipulatorStub) CreateInterface(port int) error {
 	return nil
 }
 

pkg/wg/types.go

@@ -8,14 +8,9 @@ func (m *WgError) Error() string {
 	return m.msg
 }
 
-type CreateInterfaceParams struct {
-	IfName string
-	Port   int
-}
-
 type WgInterfaceManipulator interface {
 	// CreateInterface creates a WireGuard interface
-	CreateInterface(params *CreateInterfaceParams) error
+	CreateInterface(port int) (string, error)
 	// AddAddress adds an address to the given interface name
 	AddAddress(ifName string, addr string) error
 	// RemoveInterface removes the specified interface

pkg/wg/wg.go

@@ -1,6 +1,9 @@
 package wg
 
 import (
+	"crypto"
+	"crypto/rand"
+	"encoding/base64"
 	"fmt"
 
 	"github.com/tim-beatham/wgmesh/pkg/lib"
@@ -13,40 +16,54 @@ type WgInterfaceManipulatorImpl struct {
 	client *wgctrl.Client
 }
 
+const hashLength = 6
+
 // CreateInterface creates a WireGuard interface
-func (m *WgInterfaceManipulatorImpl) CreateInterface(params *CreateInterfaceParams) error {
+func (m *WgInterfaceManipulatorImpl) CreateInterface(port int) (string, error) {
 	rtnl, err := lib.NewRtNetlinkConfig()
 
 	if err != nil {
-		return fmt.Errorf("failed to access link: %w", err)
+		return "", fmt.Errorf("failed to access link: %w", err)
 	}
 	defer rtnl.Close()
 
-	err = rtnl.CreateLink(params.IfName)
+	randomBuf := make([]byte, 32)
+	_, err = rand.Read(randomBuf)
 
 	if err != nil {
-		return fmt.Errorf("failed to create link: %w", err)
+		return "", err
+	}
+
+	md5 := crypto.MD5.New().Sum(randomBuf)
+
+	md5Str := fmt.Sprintf("wg%s", base64.StdEncoding.EncodeToString(md5)[:hashLength])
+
+	err = rtnl.CreateLink(md5Str)
+
+	if err != nil {
+		return "", fmt.Errorf("failed to create link: %w", err)
 	}
 
 	privateKey, err := wgtypes.GeneratePrivateKey()
 
 	if err != nil {
-		return fmt.Errorf("failed to create private key: %w", err)
+		return "", fmt.Errorf("failed to create private key: %w", err)
 	}
 
 	var cfg wgtypes.Config = wgtypes.Config{
 		PrivateKey: &privateKey,
-		ListenPort: &params.Port,
+		ListenPort: &port,
 	}
 
-	err = m.client.ConfigureDevice(params.IfName, cfg)
+	err = m.client.ConfigureDevice(md5Str, cfg)
 
 	if err != nil {
-		return fmt.Errorf("failed to configure dev: %w", err)
+		m.RemoveInterface(md5Str)
+		return "", fmt.Errorf("failed to configure dev: %w", err)
 	}
 
-	logging.Log.WriteInfof("ip link set up dev %s type wireguard", params.IfName)
+	logging.Log.WriteInfof("ip link set up dev %s type wireguard", md5Str)
-	return nil
+	return md5Str, nil
 }
 
 // Add an address to the given interface