tailscale/util/winutil/winutil.go
David Crawshaw 6b9f8208f4 net/dns: do not run wsl.exe as LocalSystem
It doesn't work. It needs to run as the user.

	https://github.com/microsoft/WSL/issues/4803

The mechanism for doing this was extracted from:

	https://web.archive.org/web/20101009012531/http://blogs.msdn.com/b/winsdk/archive/2009/07/14/launching-an-interactive-process-from-windows-service-in-windows-vista-and-later.aspx

While here, we also reclaculate WSL distro set on SetDNS.
This accounts for:

	1. potential inability to access wsl.exe on startup
	2. WSL being installed while Tailscale is running
	3. A new WSL distrobution being installed

Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
2021-06-30 10:11:33 -07:00

66 lines
1.8 KiB
Go

// Copyright (c) 2021 Tailscale Inc & AUTHORS All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build windows
// Package winuntil contains misc Windows/win32 helper functions.
package winutil
import (
"log"
"syscall"
"golang.org/x/sys/windows"
"golang.org/x/sys/windows/registry"
)
const RegBase = `SOFTWARE\Tailscale IPN`
// GetDesktopPID searches the PID of the process that's running the
// currently active desktop and whether it was found.
// Usually the PID will be for explorer.exe.
func GetDesktopPID() (pid uint32, ok bool) {
hwnd := windows.GetShellWindow()
if hwnd == 0 {
return 0, false
}
windows.GetWindowThreadProcessId(hwnd, &pid)
return pid, pid != 0
}
// GetRegString looks up a registry path in our local machine path, or returns
// the given default if it can't.
//
// This function will only work on GOOS=windows. Trying to run it on any other
// OS will always return the default value.
func GetRegString(name, defval string) string {
key, err := registry.OpenKey(registry.LOCAL_MACHINE, RegBase, registry.READ)
if err != nil {
log.Printf("registry.OpenKey(%v): %v", RegBase, err)
return defval
}
defer key.Close()
val, _, err := key.GetStringValue(name)
if err != nil {
if err != registry.ErrNotExist {
log.Printf("registry.GetStringValue(%v): %v", name, err)
}
return defval
}
return val
}
var (
kernel32 = syscall.NewLazyDLL("kernel32.dll")
procWTSGetActiveConsoleSessionId = kernel32.NewProc("WTSGetActiveConsoleSessionId")
)
// TODO(crawshaw): replace with x/sys/windows... one day.
// https://go-review.googlesource.com/c/sys/+/331909
func WTSGetActiveConsoleSessionId() uint32 {
r1, _, _ := procWTSGetActiveConsoleSessionId.Call()
return uint32(r1)
}