tailscale/util/winutil/winutil.go
Aaron Klotz 6e33d2da2b ipn/ipnauth, util/winutil: add temporary LookupPseudoUser workaround to address os/user.LookupId errors on Windows
I added util/winutil/LookupPseudoUser, which essentially consists of the bits
that I am in the process of adding to Go's standard library.

We check the provided SID for "S-1-5-x" where 17 <= x <= 20 (which are the
known pseudo-users) and then manually populate a os/user.User struct with
the correct information.

Fixes https://github.com/tailscale/tailscale/issues/869
Fixes https://github.com/tailscale/tailscale/issues/2894

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2022-11-28 15:53:34 -06:00

79 lines
3.1 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.
// Package winutil contains misc Windows/Win32 helper functions.
package winutil
import (
"os/user"
)
// RegBase is the registry path inside HKEY_LOCAL_MACHINE where registry settings
// are stored. This constant is a non-empty string only when GOOS=windows.
const RegBase = regBase
// GetPolicyString looks up a registry value in the local machine's path for
// system policies, or returns the given default if it can't.
// Use this function to read values that may be set by sysadmins via the MSI
// installer or via GPO. For registry settings that you do *not* want to be
// visible to sysadmin tools, use GetRegString instead.
//
// This function will only work on GOOS=windows. Trying to run it on any other
// OS will always return the default value.
func GetPolicyString(name, defval string) string {
return getPolicyString(name, defval)
}
// GetPolicyInteger looks up a registry value in the local machine's path for
// system policies, or returns the given default if it can't.
// Use this function to read values that may be set by sysadmins via the MSI
// installer or via GPO. For registry settings that you do *not* want to be
// visible to sysadmin tools, use GetRegInteger instead.
//
// This function will only work on GOOS=windows. Trying to run it on any other
// OS will always return the default value.
func GetPolicyInteger(name string, defval uint64) uint64 {
return getPolicyInteger(name, defval)
}
// GetRegString looks up a registry path in the 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 {
return getRegString(name, defval)
}
// GetRegInteger looks up a registry path in the 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 GetRegInteger(name string, defval uint64) uint64 {
return getRegInteger(name, defval)
}
// IsSIDValidPrincipal determines whether the SID contained in uid represents a
// type that is a valid security principal under Windows. This check helps us
// work around a bug in the standard library's Windows implementation of
// LookupId in os/user.
// See https://github.com/tailscale/tailscale/issues/869
//
// This function will only work on GOOS=windows. Trying to run it on any other
// OS will always return false.
func IsSIDValidPrincipal(uid string) bool {
return isSIDValidPrincipal(uid)
}
// LookupPseudoUser attempts to resolve the user specified by uid by checking
// against well-known pseudo-users on Windows. This is a temporary workaround
// until https://github.com/golang/go/issues/49509 is resolved and shipped.
//
// This function will only work on GOOS=windows. Trying to run it on any other
// OS will always return an error.
func LookupPseudoUser(uid string) (*user.User, error) {
return lookupPseudoUser(uid)
}