Update dependencies

vendor/tailscale.com/safesocket/unixsocket.go

@@ -0,0 +1,91 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+//go:build !windows && !js && !plan9
+
+package safesocket
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"net"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"runtime"
+)
+
+func connect(ctx context.Context, path string) (net.Conn, error) {
+	var std net.Dialer
+	return std.DialContext(ctx, "unix", path)
+}
+
+func listen(path string) (net.Listener, error) {
+	// Unix sockets hang around in the filesystem even after nobody
+	// is listening on them. (Which is really unfortunate but long-
+	// entrenched semantics.) Try connecting first; if it works, then
+	// the socket is still live, so let's not replace it. If it doesn't
+	// work, then replace it.
+	//
+	// Note that there's a race condition between these two steps. A
+	// "proper" daemon usually uses a dance involving pidfiles to first
+	// ensure that no other instances of itself are running, but that's
+	// beyond the scope of our simple socket library.
+	c, err := net.Dial("unix", path)
+	if err == nil {
+		c.Close()
+		if tailscaledRunningUnderLaunchd() {
+			return nil, fmt.Errorf("%v: address already in use; tailscaled already running under launchd (to stop, run: $ sudo launchctl stop com.tailscale.tailscaled)", path)
+		}
+		return nil, fmt.Errorf("%v: address already in use", path)
+	}
+	_ = os.Remove(path)
+
+	perm := socketPermissionsForOS()
+
+	sockDir := filepath.Dir(path)
+	if _, err := os.Stat(sockDir); os.IsNotExist(err) {
+		os.MkdirAll(sockDir, 0755) // best effort
+
+		// If we're on a platform where we want the socket
+		// world-readable, open up the permissions on the
+		// just-created directory too, in case a umask ate
+		// it. This primarily affects running tailscaled by
+		// hand as root in a shell, as there is no umask when
+		// running under systemd.
+		if perm == 0666 {
+			if fi, err := os.Stat(sockDir); err == nil && fi.Mode()&0077 == 0 {
+				if err := os.Chmod(sockDir, 0755); err != nil {
+					log.Print(err)
+				}
+			}
+		}
+	}
+	pipe, err := net.Listen("unix", path)
+	if err != nil {
+		return nil, err
+	}
+	os.Chmod(path, perm)
+	return pipe, err
+}
+
+func tailscaledRunningUnderLaunchd() bool {
+	if runtime.GOOS != "darwin" {
+		return false
+	}
+	plist, err := exec.Command("launchctl", "list", "com.tailscale.tailscaled").Output()
+	_ = plist // parse it? https://github.com/DHowett/go-plist if we need something.
+	running := err == nil
+	return running
+}
+
+// socketPermissionsForOS returns the permissions to use for the
+// tailscaled.sock.
+func socketPermissionsForOS() os.FileMode {
+	if PlatformUsesPeerCreds() {
+		return 0666
+	}
+	// Otherwise, root only.
+	return 0600
+}