初版功能完成

internal/overlay/clientwg/device.go

@@ -0,0 +1,84 @@
+package clientwg
+
+import (
+	"errors"
+	"fmt"
+	"log/slog"
+	"sync"
+
+	"golang.zx2c4.com/wireguard/conn"
+	"golang.zx2c4.com/wireguard/device"
+	"golang.zx2c4.com/wireguard/tun"
+)
+
+// Device owns the MuxTun, wireguard-go engine, and transport bind.
+type Device struct {
+	tun       *MuxTun
+	wireguard *device.Device
+	closeOnce sync.Once
+}
+
+// NewDevice transfers ownership of base to a new embedded wireguard-go Device.
+func NewDevice(base tun.Device, logger *slog.Logger) (*Device, error) {
+	if base == nil {
+		return nil, errors.New("base TUN device must not be nil")
+	}
+	mux := NewMuxTun(base)
+	wireguard := device.NewDevice(mux, conn.NewDefaultBind(), wireGuardLogger(logger))
+	return &Device{tun: mux, wireguard: wireguard}, nil
+}
+
+// Configure atomically replaces the single Server peer through wireguard-go UAPI.
+func (d *Device) Configure(config Config) error {
+	uapi, err := config.uapi()
+	if err != nil {
+		return err
+	}
+	if err := d.wireguard.IpcSet(uapi); err != nil {
+		return fmt.Errorf("configure embedded wireguard-go: %w", err)
+	}
+	return nil
+}
+
+// Up starts the embedded WireGuard device after configuration.
+func (d *Device) Up() error {
+	if err := d.wireguard.Up(); err != nil {
+		return fmt.Errorf("bring embedded wireguard-go up: %w", err)
+	}
+	return nil
+}
+
+// UAPIState returns wireguard-go's current UAPI state for diagnostics.
+func (d *Device) UAPIState() (string, error) {
+	return d.wireguard.IpcGet()
+}
+
+// MuxTun returns the single packet boundary used by Session transport.
+func (d *Device) MuxTun() *MuxTun { return d.tun }
+
+// Close is idempotent and stops wireguard-go, MuxTun, and the base Wintun.
+func (d *Device) Close() {
+	if d == nil || d.wireguard == nil {
+		return
+	}
+	d.closeOnce.Do(func() {
+		d.wireguard.Close()
+	})
+}
+
+func wireGuardLogger(logger *slog.Logger) *device.Logger {
+	if logger == nil {
+		return &device.Logger{
+			Verbosef: device.DiscardLogf,
+			Errorf:   device.DiscardLogf,
+		}
+	}
+	return &device.Logger{
+		Verbosef: func(format string, args ...any) {
+			logger.Debug(fmt.Sprintf(format, args...))
+		},
+		Errorf: func(format string, args ...any) {
+			logger.Error(fmt.Sprintf(format, args...))
+		},
+	}
+}