[client] Refactor/iface pkg (#2646)

Refactor the flat code structure

client/iface/device/device_usp_unix.go

@@ -0,0 +1,145 @@
+//go:build (linux && !android) || freebsd
+
+package device
+
+import (
+	"fmt"
+	"os"
+	"runtime"
+
+	"github.com/pion/transport/v3"
+	log "github.com/sirupsen/logrus"
+	"golang.zx2c4.com/wireguard/device"
+	"golang.zx2c4.com/wireguard/tun"
+
+	"github.com/netbirdio/netbird/client/iface/bind"
+	"github.com/netbirdio/netbird/client/iface/configurer"
+)
+
+type USPDevice struct {
+	name    string
+	address WGAddress
+	port    int
+	key     string
+	mtu     int
+	iceBind *bind.ICEBind
+
+	device         *device.Device
+	filteredDevice *FilteredDevice
+	udpMux         *bind.UniversalUDPMuxDefault
+	configurer     WGConfigurer
+}
+
+func NewUSPDevice(name string, address WGAddress, port int, key string, mtu int, transportNet transport.Net, filterFn bind.FilterFn) *USPDevice {
+	log.Infof("using userspace bind mode")
+
+	checkUser()
+
+	return &USPDevice{
+		name:    name,
+		address: address,
+		port:    port,
+		key:     key,
+		mtu:     mtu,
+		iceBind: bind.NewICEBind(transportNet, filterFn)}
+}
+
+func (t *USPDevice) Create() (WGConfigurer, error) {
+	log.Info("create tun interface")
+	tunIface, err := tun.CreateTUN(t.name, t.mtu)
+	if err != nil {
+		log.Debugf("failed to create tun interface (%s, %d): %s", t.name, t.mtu, err)
+		return nil, fmt.Errorf("error creating tun device: %s", err)
+	}
+	t.filteredDevice = newDeviceFilter(tunIface)
+
+	// We need to create a wireguard-go device and listen to configuration requests
+	t.device = device.NewDevice(
+		t.filteredDevice,
+		t.iceBind,
+		device.NewLogger(wgLogLevel(), "[netbird] "),
+	)
+
+	err = t.assignAddr()
+	if err != nil {
+		t.device.Close()
+		return nil, fmt.Errorf("error assigning ip: %s", err)
+	}
+
+	t.configurer = configurer.NewUSPConfigurer(t.device, t.name)
+	err = t.configurer.ConfigureInterface(t.key, t.port)
+	if err != nil {
+		t.device.Close()
+		t.configurer.Close()
+		return nil, fmt.Errorf("error configuring interface: %s", err)
+	}
+	return t.configurer, nil
+}
+
+func (t *USPDevice) Up() (*bind.UniversalUDPMuxDefault, error) {
+	if t.device == nil {
+		return nil, fmt.Errorf("device is not ready yet")
+	}
+
+	err := t.device.Up()
+	if err != nil {
+		return nil, err
+	}
+
+	udpMux, err := t.iceBind.GetICEMux()
+	if err != nil {
+		return nil, err
+	}
+	t.udpMux = udpMux
+
+	log.Debugf("device is ready to use: %s", t.name)
+	return udpMux, nil
+}
+
+func (t *USPDevice) UpdateAddr(address WGAddress) error {
+	t.address = address
+	return t.assignAddr()
+}
+
+func (t *USPDevice) Close() error {
+	if t.configurer != nil {
+		t.configurer.Close()
+	}
+
+	if t.device != nil {
+		t.device.Close()
+	}
+
+	if t.udpMux != nil {
+		return t.udpMux.Close()
+	}
+	return nil
+}
+
+func (t *USPDevice) WgAddress() WGAddress {
+	return t.address
+}
+
+func (t *USPDevice) DeviceName() string {
+	return t.name
+}
+
+func (t *USPDevice) FilteredDevice() *FilteredDevice {
+	return t.filteredDevice
+}
+
+// assignAddr Adds IP address to the tunnel interface
+func (t *USPDevice) assignAddr() error {
+	link := newWGLink(t.name)
+
+	return link.assignAddr(t.address)
+}
+
+func checkUser() {
+	if runtime.GOOS == "freebsd" {
+		euid := os.Geteuid()
+		if euid != 0 {
+			log.Warn("newTunUSPDevice: on netbird must run as root to be able to assign address to the tun interface with ifconfig")
+		}
+	}
+}