EtherGuard-VPN/tun/wintun/wintun_windows.go
Simon Rozman 6c1b66802f wintun: registry: revise value reading
- Make getStringValueRetry() reusable for reading any value type. This
  merges code from GetIntegerValueWait().
- expandString() >> toString() and extend to support REG_MULTI_SZ
  (to return first value of REG_MULTI_SZ). Furthermore, doing our own
  UTF-16 to UTF-8 conversion works around a bug in windows/registry's
  GetStringValue() non-zero terminated string handling.
- Provide toInteger() analogous to toString()
- GetStringValueWait() tolerates and reads REG_MULTI_SZ too now. It
  returns REG_MULTI_SZ[0], making GetFirstStringValueWait() redundant.

Signed-off-by: Simon Rozman <simon@rozman.si>
2019-05-11 17:14:37 +02:00

570 lines
19 KiB
Go

/* SPDX-License-Identifier: MIT
*
* Copyright (C) 2019 WireGuard LLC. All Rights Reserved.
*/
package wintun
import (
"errors"
"fmt"
"strings"
"syscall"
"time"
"unsafe"
"golang.org/x/sys/windows"
"golang.org/x/sys/windows/registry"
"golang.zx2c4.com/wireguard/tun/wintun/guid"
"golang.zx2c4.com/wireguard/tun/wintun/netshell"
registryEx "golang.zx2c4.com/wireguard/tun/wintun/registry"
"golang.zx2c4.com/wireguard/tun/wintun/setupapi"
)
//
// Wintun is a handle of a Wintun adapter
//
type Wintun struct {
CfgInstanceID windows.GUID
LUIDIndex uint32
IfType uint32
}
var deviceClassNetGUID = windows.GUID{Data1: 0x4d36e972, Data2: 0xe325, Data3: 0x11ce, Data4: [8]byte{0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}}
const hardwareID = "Wintun"
const enumerator = ""
const machineName = ""
const waitForRegistryTimeout = time.Second * 5
//
// MakeWintun creates interface handle and populates it from device registry key
//
func makeWintun(deviceInfoSet setupapi.DevInfo, deviceInfoData *setupapi.DevInfoData) (*Wintun, error) {
// Open HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\<class>\<id> registry key.
key, err := deviceInfoSet.OpenDevRegKey(deviceInfoData, setupapi.DICS_FLAG_GLOBAL, 0, setupapi.DIREG_DRV, registry.QUERY_VALUE)
if err != nil {
return nil, fmt.Errorf("Device-specific registry key open failed: %v", err)
}
defer key.Close()
// Read the NetCfgInstanceId value.
valueStr, err := registryEx.GetStringValue(key, "NetCfgInstanceId")
if err != nil {
return nil, fmt.Errorf("RegQueryStringValue(\"NetCfgInstanceId\") failed: %v", err)
}
// Convert to windows.GUID.
ifid, err := guid.FromString(valueStr)
if err != nil {
return nil, fmt.Errorf("NetCfgInstanceId registry value is not a GUID (expected: \"{...}\", provided: %q)", valueStr)
}
// Read the NetLuidIndex value.
luidIdx, _, err := key.GetIntegerValue("NetLuidIndex")
if err != nil {
return nil, fmt.Errorf("RegQueryValue(\"NetLuidIndex\") failed: %v", err)
}
// Read the NetLuidIndex value.
ifType, _, err := key.GetIntegerValue("*IfType")
if err != nil {
return nil, fmt.Errorf("RegQueryValue(\"*IfType\") failed: %v", err)
}
return &Wintun{
CfgInstanceID: *ifid,
LUIDIndex: uint32(luidIdx),
IfType: uint32(ifType),
}, nil
}
//
// GetInterface finds interface by name.
//
// hwndParent is a handle to the top-level window to use for any user
// interface that is related to non-device-specific actions (such as a select-
// device dialog box that uses the global class driver list). This handle is
// optional and can be 0. If a specific top-level window is not required, set
// hwndParent to 0.
//
// Function returns interface if found, or nil otherwise. If the interface is
// found but not Wintun-class, the function returns interface and an error.
//
func GetInterface(ifname string, hwndParent uintptr) (*Wintun, error) {
// Create a list of network devices.
devInfoList, err := setupapi.SetupDiGetClassDevsEx(&deviceClassNetGUID, enumerator, hwndParent, setupapi.DIGCF_PRESENT, setupapi.DevInfo(0), machineName)
if err != nil {
return nil, fmt.Errorf("SetupDiGetClassDevsEx(%s) failed: %v", guid.ToString(&deviceClassNetGUID), err)
}
defer devInfoList.Close()
// Windows requires each interface to have a different name. When
// enforcing this, Windows treats interface names case-insensitive. If an
// interface "FooBar" exists and this function reports there is no
// interface "foobar", an attempt to create a new interface and name it
// "foobar" would cause conflict with "FooBar".
ifname = strings.ToLower(ifname)
for index := 0; ; index++ {
// Get the device from the list. Should anything be wrong with this device, continue with next.
deviceData, err := devInfoList.EnumDeviceInfo(index)
if err != nil {
if errWin, ok := err.(syscall.Errno); ok && errWin == windows.ERROR_NO_MORE_ITEMS {
break
}
continue
}
// Get interface ID.
wintun, err := makeWintun(devInfoList, deviceData)
if err != nil {
continue
}
//TODO: is there a better way than comparing ifnames?
// Get interface name.
ifname2, err := wintun.GetInterfaceName()
if err != nil {
continue
}
if ifname == strings.ToLower(ifname2) {
// Interface name found. Check its driver.
const driverType = setupapi.SPDIT_COMPATDRIVER
err = devInfoList.BuildDriverInfoList(deviceData, driverType)
if err != nil {
return nil, fmt.Errorf("SetupDiBuildDriverInfoList failed: %v", err)
}
defer devInfoList.DestroyDriverInfoList(deviceData, driverType)
for index := 0; ; index++ {
// Get a driver from the list.
driverData, err := devInfoList.EnumDriverInfo(deviceData, driverType, index)
if err != nil {
if errWin, ok := err.(syscall.Errno); ok && errWin == windows.ERROR_NO_MORE_ITEMS {
break
}
// Something is wrong with this driver. Skip it.
continue
}
// Get driver info details.
driverDetailData, err := devInfoList.GetDriverInfoDetail(deviceData, driverData)
if err != nil {
// Something is wrong with this driver. Skip it.
continue
}
if driverDetailData.IsCompatible(hardwareID) {
// Matching hardware ID found.
return wintun, nil
}
}
// This interface is not using Wintun driver.
return nil, errors.New("Foreign network interface with the same name exists")
}
}
return nil, nil
}
//
// CreateInterface creates a TUN interface.
//
// description is a string that supplies the text description of the device.
// description is optional and can be "".
//
// hwndParent is a handle to the top-level window to use for any user
// interface that is related to non-device-specific actions (such as a select-
// device dialog box that uses the global class driver list). This handle is
// optional and can be 0. If a specific top-level window is not required, set
// hwndParent to 0.
//
// Function returns the network interface ID and a flag if reboot is required.
//
func CreateInterface(description string, hwndParent uintptr) (*Wintun, bool, error) {
// Create an empty device info set for network adapter device class.
devInfoList, err := setupapi.SetupDiCreateDeviceInfoListEx(&deviceClassNetGUID, hwndParent, machineName)
if err != nil {
return nil, false, fmt.Errorf("SetupDiCreateDeviceInfoListEx(%s) failed: %v", guid.ToString(&deviceClassNetGUID), err)
}
defer devInfoList.Close()
// Get the device class name from GUID.
className, err := setupapi.SetupDiClassNameFromGuidEx(&deviceClassNetGUID, machineName)
if err != nil {
return nil, false, fmt.Errorf("SetupDiClassNameFromGuidEx(%s) failed: %v", guid.ToString(&deviceClassNetGUID), err)
}
// Create a new device info element and add it to the device info set.
deviceData, err := devInfoList.CreateDeviceInfo(className, &deviceClassNetGUID, description, hwndParent, setupapi.DICD_GENERATE_ID)
if err != nil {
return nil, false, fmt.Errorf("SetupDiCreateDeviceInfo failed: %v", err)
}
// Set a device information element as the selected member of a device information set.
err = devInfoList.SetSelectedDevice(deviceData)
if err != nil {
return nil, false, fmt.Errorf("SetupDiSetSelectedDevice failed: %v", err)
}
// Set Plug&Play device hardware ID property.
err = devInfoList.SetDeviceRegistryPropertyString(deviceData, setupapi.SPDRP_HARDWAREID, hardwareID)
if err != nil {
return nil, false, fmt.Errorf("SetupDiSetDeviceRegistryProperty(SPDRP_HARDWAREID) failed: %v", err)
}
// Search for the driver.
const driverType = setupapi.SPDIT_COMPATDRIVER
err = devInfoList.BuildDriverInfoList(deviceData, driverType) //TODO: This takes ~510ms
if err != nil {
return nil, false, fmt.Errorf("SetupDiBuildDriverInfoList failed: %v", err)
}
defer devInfoList.DestroyDriverInfoList(deviceData, driverType)
driverDate := windows.Filetime{}
driverVersion := uint64(0)
for index := 0; ; index++ { //TODO: This loop takes ~600ms
// Get a driver from the list.
driverData, err := devInfoList.EnumDriverInfo(deviceData, driverType, index)
if err != nil {
if errWin, ok := err.(syscall.Errno); ok && errWin == windows.ERROR_NO_MORE_ITEMS {
break
}
// Something is wrong with this driver. Skip it.
continue
}
// Check the driver version first, since the check is trivial and will save us iterating over hardware IDs for any driver versioned prior our best match.
if driverData.IsNewer(driverDate, driverVersion) {
// Get driver info details.
driverDetailData, err := devInfoList.GetDriverInfoDetail(deviceData, driverData)
if err != nil {
// Something is wrong with this driver. Skip it.
continue
}
if driverDetailData.IsCompatible(hardwareID) {
// Matching hardware ID found. Select the driver.
err := devInfoList.SetSelectedDriver(deviceData, driverData)
if err != nil {
// Something is wrong with this driver. Skip it.
continue
}
driverDate = driverData.DriverDate
driverVersion = driverData.DriverVersion
}
}
}
if driverVersion == 0 {
return nil, false, fmt.Errorf("No driver for device %q installed", hardwareID)
}
// Call appropriate class installer.
err = devInfoList.CallClassInstaller(setupapi.DIF_REGISTERDEVICE, deviceData)
if err != nil {
return nil, false, fmt.Errorf("SetupDiCallClassInstaller(DIF_REGISTERDEVICE) failed: %v", err)
}
// Register device co-installers if any. (Ignore errors)
devInfoList.CallClassInstaller(setupapi.DIF_REGISTER_COINSTALLERS, deviceData)
// Install interfaces if any. (Ignore errors)
devInfoList.CallClassInstaller(setupapi.DIF_INSTALLINTERFACES, deviceData)
// Install the device.
err = devInfoList.CallClassInstaller(setupapi.DIF_INSTALLDEVICE, deviceData)
if err != nil {
err = fmt.Errorf("SetupDiCallClassInstaller(DIF_INSTALLDEVICE) failed: %v", err)
}
var wintun *Wintun
var rebootRequired bool
var key registry.Key
if err == nil {
// Check if a system reboot is required. (Ignore errors)
if ret, _ := checkReboot(devInfoList, deviceData); ret {
rebootRequired = true
}
// DIF_INSTALLDEVICE returns almost immediately, while the device installation
// continues in the background. It might take a while, before all registry
// keys and values are populated.
const pollTimeout = time.Millisecond * 50
for i := 0; i < int(waitForRegistryTimeout/pollTimeout); i++ {
if i != 0 {
time.Sleep(pollTimeout)
}
key, err = devInfoList.OpenDevRegKey(deviceData, setupapi.DICS_FLAG_GLOBAL, 0, setupapi.DIREG_DRV, registry.QUERY_VALUE|registry.NOTIFY)
if err == nil {
break
}
}
if err == nil {
_, err = registryEx.GetStringValueWait(key, "NetCfgInstanceId", waitForRegistryTimeout)
if err == nil {
_, err = registryEx.GetIntegerValueWait(key, "NetLuidIndex", waitForRegistryTimeout)
}
if err == nil {
_, err = registryEx.GetIntegerValueWait(key, "*IfType", waitForRegistryTimeout)
}
key.Close()
}
}
if err == nil {
// Get network interface.
wintun, err = makeWintun(devInfoList, deviceData)
}
if err == nil {
// Wait for network registry key to emerge and populate.
key, err = registryEx.OpenKeyWait(
registry.LOCAL_MACHINE,
wintun.GetNetRegKeyName(),
registry.QUERY_VALUE|registry.NOTIFY,
waitForRegistryTimeout)
if err == nil {
_, err = registryEx.GetStringValueWait(key, "Name", waitForRegistryTimeout)
key.Close()
}
}
if err == nil {
// Wait for TCP/IP adapter registry key to emerge and populate.
key, err = registryEx.OpenKeyWait(
registry.LOCAL_MACHINE,
wintun.GetTcpipAdapterRegKeyName(), registry.QUERY_VALUE|registry.NOTIFY,
waitForRegistryTimeout)
if err == nil {
_, err = registryEx.GetStringValueWait(key, "IpConfig", waitForRegistryTimeout)
key.Close()
}
}
var tcpipInterfaceRegKeyName string
if err == nil {
tcpipInterfaceRegKeyName, err = wintun.GetTcpipInterfaceRegKeyName()
if err == nil {
// Wait for TCP/IP interface registry key to emerge.
key, err = registryEx.OpenKeyWait(
registry.LOCAL_MACHINE,
tcpipInterfaceRegKeyName, registry.QUERY_VALUE,
waitForRegistryTimeout)
if err == nil {
key.Close()
}
}
}
//
// All the registry keys and values we're relying on are present now.
//
if err == nil {
// Disable dead gateway detection on our interface.
key, err = registry.OpenKey(registry.LOCAL_MACHINE, tcpipInterfaceRegKeyName, registry.SET_VALUE)
if err != nil {
err = fmt.Errorf("Error opening interface-specific TCP/IP network registry key: %v", err)
}
key.SetDWordValue("EnableDeadGWDetect", 0)
key.Close()
}
if err == nil {
return wintun, rebootRequired, nil
}
// The interface failed to install, or the interface ID was unobtainable. Clean-up.
removeDeviceParams := setupapi.RemoveDeviceParams{
ClassInstallHeader: *setupapi.MakeClassInstallHeader(setupapi.DIF_REMOVE),
Scope: setupapi.DI_REMOVEDEVICE_GLOBAL,
}
// Set class installer parameters for DIF_REMOVE.
if devInfoList.SetClassInstallParams(deviceData, &removeDeviceParams.ClassInstallHeader, uint32(unsafe.Sizeof(removeDeviceParams))) == nil {
// Call appropriate class installer.
if devInfoList.CallClassInstaller(setupapi.DIF_REMOVE, deviceData) == nil {
// Check if a system reboot is required. (Ignore errors)
if ret, _ := checkReboot(devInfoList, deviceData); ret {
rebootRequired = true
}
}
}
return nil, rebootRequired, err
}
//
// DeleteInterface deletes a TUN interface.
//
// hwndParent is a handle to the top-level window to use for any user
// interface that is related to non-device-specific actions (such as a select-
// device dialog box that uses the global class driver list). This handle is
// optional and can be 0. If a specific top-level window is not required, set
// hwndParent to 0.
//
// Function returns true if the interface was found and deleted and a flag if
// reboot is required.
//
func (wintun *Wintun) DeleteInterface(hwndParent uintptr) (bool, bool, error) {
// Create a list of network devices.
devInfoList, err := setupapi.SetupDiGetClassDevsEx(&deviceClassNetGUID, enumerator, hwndParent, setupapi.DIGCF_PRESENT, setupapi.DevInfo(0), machineName)
if err != nil {
return false, false, fmt.Errorf("SetupDiGetClassDevsEx(%s) failed: %v", guid.ToString(&deviceClassNetGUID), err.Error())
}
defer devInfoList.Close()
// Iterate.
for index := 0; ; index++ {
// Get the device from the list. Should anything be wrong with this device, continue with next.
deviceData, err := devInfoList.EnumDeviceInfo(index)
if err != nil {
if errWin, ok := err.(syscall.Errno); ok && errWin == windows.ERROR_NO_MORE_ITEMS {
break
}
continue
}
// Get interface ID.
//TODO: Store some ID in the Wintun object such that this call isn't required.
wintun2, err := makeWintun(devInfoList, deviceData)
if err != nil {
continue
}
if wintun.CfgInstanceID == wintun2.CfgInstanceID {
// Remove the device.
removeDeviceParams := setupapi.RemoveDeviceParams{
ClassInstallHeader: *setupapi.MakeClassInstallHeader(setupapi.DIF_REMOVE),
Scope: setupapi.DI_REMOVEDEVICE_GLOBAL,
}
// Set class installer parameters for DIF_REMOVE.
err = devInfoList.SetClassInstallParams(deviceData, &removeDeviceParams.ClassInstallHeader, uint32(unsafe.Sizeof(removeDeviceParams)))
if err != nil {
return false, false, fmt.Errorf("SetupDiSetClassInstallParams failed: %v", err)
}
// Call appropriate class installer.
err = devInfoList.CallClassInstaller(setupapi.DIF_REMOVE, deviceData)
if err != nil {
return false, false, fmt.Errorf("SetupDiCallClassInstaller failed: %v", err)
}
// Check if a system reboot is required. (Ignore errors)
if ret, _ := checkReboot(devInfoList, deviceData); ret {
return true, true, nil
}
return true, false, nil
}
}
return false, false, nil
}
//
// FlushInterface removes all properties from the interface and gives it only a very
// vanilla IPv4 and IPv6 configuration with no addresses of any sort assigned.
//
func (wintun *Wintun) FlushInterface() error {
//TODO: implement me!
return nil
}
//
// checkReboot checks device install parameters if a system reboot is required.
//
func checkReboot(deviceInfoSet setupapi.DevInfo, deviceInfoData *setupapi.DevInfoData) (bool, error) {
devInstallParams, err := deviceInfoSet.GetDeviceInstallParams(deviceInfoData)
if err != nil {
return false, err
}
if (devInstallParams.Flags & (setupapi.DI_NEEDREBOOT | setupapi.DI_NEEDRESTART)) != 0 {
return true, nil
}
return false, nil
}
//
// GetInterfaceName returns network interface name.
//
func (wintun *Wintun) GetInterfaceName() (string, error) {
key, err := registry.OpenKey(registry.LOCAL_MACHINE, wintun.GetNetRegKeyName(), registry.QUERY_VALUE)
if err != nil {
return "", fmt.Errorf("Network-specific registry key open failed: %v", err)
}
defer key.Close()
// Get the interface name.
return registryEx.GetStringValue(key, "Name")
}
//
// SetInterfaceName sets network interface name.
//
func (wintun *Wintun) SetInterfaceName(ifname string) error {
// We have to tell the various runtime COM services about the new name too. We ignore the
// error because netshell isn't available on servercore. It's also slow, so we run it in a
// separate thread.
// TODO: netsh.exe falls back to NciSetConnection in this case. If somebody complains, maybe
// we should do the same.
go netshell.HrRenameConnection(&wintun.CfgInstanceID, windows.StringToUTF16Ptr(ifname))
// Set the interface name. The above line should have done this too, but in case it failed, we force it.
key, err := registry.OpenKey(registry.LOCAL_MACHINE, wintun.GetNetRegKeyName(), registry.SET_VALUE)
if err != nil {
return fmt.Errorf("Network-specific registry key open failed: %v", err)
}
defer key.Close()
return key.SetStringValue("Name", ifname)
}
//
// GetNetRegKeyName returns interface-specific network registry key name.
//
func (wintun *Wintun) GetNetRegKeyName() string {
return fmt.Sprintf("SYSTEM\\CurrentControlSet\\Control\\Network\\%s\\%s\\Connection", guid.ToString(&deviceClassNetGUID), guid.ToString(&wintun.CfgInstanceID))
}
//
// GetTcpipAdapterRegKeyName returns adapter-specific TCP/IP network registry key name.
//
func (wintun *Wintun) GetTcpipAdapterRegKeyName() string {
return fmt.Sprintf("SYSTEM\\CurrentControlSet\\Services\\Tcpip\\Parameters\\Adapters\\%s", guid.ToString(&wintun.CfgInstanceID))
}
//
// GetTcpipInterfaceRegKeyName returns interface-specific TCP/IP network registry key name.
//
func (wintun *Wintun) GetTcpipInterfaceRegKeyName() (path string, err error) {
key, err := registry.OpenKey(registry.LOCAL_MACHINE, wintun.GetTcpipAdapterRegKeyName(), registry.QUERY_VALUE)
if err != nil {
return "", fmt.Errorf("Error opening adapter-specific TCP/IP network registry key: %v", err)
}
paths, _, err := key.GetStringsValue("IpConfig")
key.Close()
if err != nil {
return "", fmt.Errorf("Error reading IpConfig registry key: %v", err)
}
if len(paths) == 0 {
return "", errors.New("No TCP/IP interfaces found on adapter")
}
return fmt.Sprintf("SYSTEM\\CurrentControlSet\\Services\\%s", paths[0]), nil
}
//
// DataFileName returns Wintun device data pipe name.
//
func (wintun *Wintun) DataFileName() string {
return fmt.Sprintf("\\\\.\\Global\\WINTUN%d", wintun.LUIDIndex)
}