fixup non-darwin tun

ethanndickson · ethanndickson · commit e03f240438dc · 2024-11-21T05:08:45.000Z
diff --git a/vpn/tun.go b/vpn/tun.go
@@ -0,0 +1,10 @@
+//go:build !darwin
+
+package vpn
+
+import "github.com/tailscale/wireguard-go/tun"
+
+// This is a no-op on non-Darwin platforms.
+func makeTUN(int) (tun.Device, error) {
+	return nil, nil
+}
diff --git a/vpn/tun_darwin.go b/vpn/tun_darwin.go
@@ -0,0 +1,30 @@
+//go:build darwin
+
+package vpn
+
+import (
+	"os"
+
+	"github.com/tailscale/wireguard-go/tun"
+	"golang.org/x/sys/unix"
+	"golang.org/x/xerrors"
+)
+
+func makeTUN(tunFD int) (tun.Device, error) {
+	dupTunFd, err := unix.Dup(tunFD)
+	if err != nil {
+		return nil, xerrors.Errorf("dup tun fd: %w", err)
+	}
+
+	err = unix.SetNonblock(dupTunFd, true)
+	if err != nil {
+		unix.Close(dupTunFd)
+		return nil, xerrors.Errorf("set nonblock: %w", err)
+	}
+	fileTun, err := tun.CreateTUNFromFile(os.NewFile(uintptr(dupTunFd), "/dev/tun"), 0)
+	if err != nil {
+		unix.Close(dupTunFd)
+		return nil, xerrors.Errorf("create TUN from File: %w", err)
+	}
+	return fileTun, nil
+}
diff --git a/vpn/tunnel.go b/vpn/tunnel.go
@@ -8,17 +8,14 @@ import (
 	"io"
 	"net/http"
 	"net/url"
-	"os"
 	"reflect"
 	"strconv"
 	"sync"
 	"unicode"
 
-	"golang.org/x/sys/unix"
 	"golang.org/x/xerrors"
 
 	"github.com/hashicorp/go-multierror"
-	"github.com/tailscale/wireguard-go/tun"
 
 	"github.com/coder/coder/v2/codersdk"
 	"github.com/coder/coder/v2/tailnet/proto"
@@ -185,6 +182,7 @@ func (t *Tunnel) start(req *StartRequest) error {
 	}
 	sdk.HTTPClient.Transport = transport
 
+	// No-op on non-Darwin platforms.
 	dev, err := makeTUN(int(req.GetTunnelFileDescriptor()))
 	if err != nil {
 		return xerrors.Errorf("make TUN: %w", err)
@@ -317,25 +315,6 @@ func quote(key string) string {
 	return quoted
 }
 
-func makeTUN(tunFD int) (tun.Device, error) {
-	dupTunFd, err := unix.Dup(tunFD)
-	if err != nil {
-		return nil, xerrors.Errorf("dup tun fd: %w", err)
-	}
-
-	err = unix.SetNonblock(dupTunFd, true)
-	if err != nil {
-		unix.Close(dupTunFd)
-		return nil, xerrors.Errorf("set nonblock: %w", err)
-	}
-	fileTun, err := tun.CreateTUNFromFile(os.NewFile(uintptr(dupTunFd), "/dev/tun"), 0)
-	if err != nil {
-		unix.Close(dupTunFd)
-		return nil, xerrors.Errorf("create TUN from File: %w", err)
-	}
-	return fileTun, nil
-}
-
 func convertWorkspaceUpdate(update *proto.WorkspaceUpdate) *PeerUpdate {
 	out := &PeerUpdate{
 		UpsertedWorkspaces: make([]*Workspace, len(update.UpsertedWorkspaces)),
