wintun: Revise interface creation wait

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.

Previously, wireguard-go waited for HKLM\SYSTEM\CurrentControlSet\
Control\Class\{4D36E972-E325-11CE-BFC1-08002BE10318}\<id> registry key
only.

Followed by a SetInterfaceName() method of Wintun struct which tried to
access HKLM\SYSTEM\CurrentControlSet\Control\Network\
{4D36E972-E325-11CE-BFC1-08002BE10318}\<id>\Connection registry key
might not be available yet.

This commit loops until both registry keys are available before
returning from CreateInterface() function.

Signed-off-by: Simon Rozman <simon@rozman.si>
This commit is contained in:
Simon Rozman 2019-03-07 15:19:27 +01:00 committed by Jason A. Donenfeld
parent 26af6c4651
commit 11f5780250
3 changed files with 106 additions and 59 deletions

View file

@ -7,12 +7,14 @@ package setupapi
import (
"encoding/binary"
"errors"
"fmt"
"syscall"
"unsafe"
"golang.org/x/sys/windows"
"golang.org/x/sys/windows/registry"
"golang.zx2c4.com/wireguard/tun/wintun/guid"
)
//sys setupDiCreateDeviceInfoListEx(classGUID *windows.GUID, hwndParent uintptr, machineName *uint16, reserved uintptr) (handle DevInfo, err error) [failretval==DevInfo(windows.InvalidHandle)] = setupapi.SetupDiCreateDeviceInfoListExW
@ -234,6 +236,33 @@ func (deviceInfoSet DevInfo) OpenDevRegKey(DeviceInfoData *DevInfoData, Scope DI
return SetupDiOpenDevRegKey(deviceInfoSet, DeviceInfoData, Scope, HwProfile, KeyType, samDesired)
}
// GetInterfaceID method returns network interface ID.
func (deviceInfoSet DevInfo) GetInterfaceID(deviceInfoData *DevInfoData) (*windows.GUID, error) {
// Open HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\<class>\<id> registry key.
key, err := deviceInfoSet.OpenDevRegKey(deviceInfoData, DICS_FLAG_GLOBAL, 0, DIREG_DRV, registry.READ)
if err != nil {
return nil, errors.New("Device-specific registry key open failed: " + err.Error())
}
defer key.Close()
// Read the NetCfgInstanceId value.
value, valueType, err := key.GetStringValue("NetCfgInstanceId")
if err != nil {
return nil, errors.New("RegQueryStringValue(\"NetCfgInstanceId\") failed: " + err.Error())
}
if valueType != registry.SZ {
return nil, fmt.Errorf("NetCfgInstanceId registry value is not REG_SZ (expected: %v, provided: %v)", registry.SZ, valueType)
}
// Convert to windows.GUID.
ifid, err := guid.FromString(value)
if err != nil {
return nil, fmt.Errorf("NetCfgInstanceId registry value is not a GUID (expected: \"{...}\", provided: \"%v\")", value)
}
return ifid, nil
}
//sys setupDiGetDeviceRegistryProperty(deviceInfoSet DevInfo, deviceInfoData *DevInfoData, property SPDRP, propertyRegDataType *uint32, propertyBuffer *byte, propertyBufferSize uint32, requiredSize *uint32) (err error) = setupapi.SetupDiGetDeviceRegistryPropertyW
// SetupDiGetDeviceRegistryProperty function retrieves a specified Plug and Play device property.

View file

@ -291,6 +291,11 @@ func TestSetupDiOpenDevRegKey(t *testing.T) {
t.Errorf("Error calling SetupDiOpenDevRegKey: %s", err.Error())
}
defer key.Close()
_, err = devInfoList.GetInterfaceID(data)
if err != nil {
t.Errorf("Error calling GetInterfaceID: %s", err.Error())
}
}
}

View file

@ -58,27 +58,24 @@ func GetInterface(ifname string, hwndParent uintptr) (*Wintun, error) {
// Iterate.
for index := 0; ; index++ {
// Get the device from the list.
// 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 == 259 /*ERROR_NO_MORE_ITEMS*/ {
break
}
// Something is wrong with this device. Skip it.
continue
}
// Get interface ID.
ifid, err := getInterfaceID(devInfoList, deviceData, 1)
ifid, err := devInfoList.GetInterfaceID(deviceData)
if err != nil {
// Something is wrong with this device. Skip it.
continue
}
// Get interface name.
ifname2, err := ((*Wintun)(ifid)).GetInterfaceName()
if err != nil {
// Something is wrong with this device. Skip it.
continue
}
@ -243,8 +240,74 @@ func CreateInterface(description string, hwndParent uintptr) (*Wintun, bool, err
rebootRequired = true
}
// Get network interface ID from registry. Retry for max 30sec.
ifid, err = getInterfaceID(devInfoList, deviceData, 30)
// Get network interface ID from registry. 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.
getInterfaceID := func() (*windows.GUID, error) {
// Open HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\<class>\<id> registry key.
keyDev, err := devInfoList.OpenDevRegKey(deviceData, setupapi.DICS_FLAG_GLOBAL, 0, setupapi.DIREG_DRV, registry.READ)
if err != nil {
return nil, errors.New("Device-specific registry key open failed: " + err.Error())
}
defer keyDev.Close()
// Read the NetCfgInstanceId value.
value, err := getRegStringValue(keyDev, "NetCfgInstanceId")
if err != nil {
if errWin, ok := err.(syscall.Errno); ok && errWin == windows.ERROR_FILE_NOT_FOUND {
return nil, err
}
return nil, errors.New("RegQueryStringValue(\"NetCfgInstanceId\") failed: " + err.Error())
}
// Convert to windows.GUID.
ifid, err := guid.FromString(value)
if err != nil {
return nil, fmt.Errorf("NetCfgInstanceId registry value is not a GUID (expected: \"{...}\", provided: \"%v\")", value)
}
keyNetName := fmt.Sprintf("SYSTEM\\CurrentControlSet\\Control\\Network\\%v\\%v\\Connection", guid.ToString(&deviceClassNetGUID), value)
keyNet, err := registry.OpenKey(registry.LOCAL_MACHINE, keyNetName, registry.QUERY_VALUE)
if err != nil {
if errWin, ok := err.(syscall.Errno); ok && errWin == windows.ERROR_FILE_NOT_FOUND {
return nil, err
}
return nil, errors.New(fmt.Sprintf("RegOpenKeyEx(\"%v\") failed: ", keyNetName) + err.Error())
}
defer keyNet.Close()
// Query the interface name.
_, valueType, err := keyNet.GetValue("Name", nil)
if err != nil {
if errWin, ok := err.(syscall.Errno); ok && errWin == windows.ERROR_FILE_NOT_FOUND {
return nil, err
}
return nil, errors.New("RegQueryValueEx(\"Name\") failed: " + err.Error())
}
switch valueType {
case registry.SZ, registry.EXPAND_SZ:
default:
return nil, fmt.Errorf("Interface name registry value is not REG_SZ or REG_EXPAND_SZ (expected: %v or %v, provided: %v)", registry.SZ, registry.EXPAND_SZ, valueType)
}
// TUN interface is ready. (As far as we need it.)
return ifid, nil
}
for numAttempts := 0; numAttempts < 30; numAttempts++ {
ifid, err = getInterfaceID()
if err != nil {
if errWin, ok := err.(syscall.Errno); ok && errWin == windows.ERROR_FILE_NOT_FOUND {
// Wait and retry. TODO: Wait for a cancellable event instead.
time.Sleep(1000 * time.Millisecond)
continue
}
}
break
}
}
if err == nil {
@ -294,20 +357,18 @@ func (wintun *Wintun) DeleteInterface(hwndParent uintptr) (bool, bool, error) {
// Iterate.
for index := 0; ; index++ {
// Get the device from the list.
// 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 == 259 /*ERROR_NO_MORE_ITEMS*/ {
break
}
// Something is wrong with this device. Skip it.
continue
}
// Get interface ID.
ifid2, err := getInterfaceID(devInfoList, deviceData, 1)
ifid2, err := devInfoList.GetInterfaceID(deviceData)
if err != nil {
// Something is wrong with this device. Skip it.
continue
}
@ -367,54 +428,6 @@ func checkReboot(deviceInfoSet setupapi.DevInfo, deviceInfoData *setupapi.DevInf
return false, nil
}
// getInterfaceID returns network interface ID.
//
// After the device is created, it might take some time before the registry
// key is populated. numAttempts parameter specifies the number of attempts
// to read NetCfgInstanceId value from registry. A 1sec sleep is inserted
// between retry attempts.
//
// Function returns the network interface ID.
//
func getInterfaceID(deviceInfoSet setupapi.DevInfo, deviceInfoData *setupapi.DevInfoData, numAttempts int) (*windows.GUID, error) {
if numAttempts < 1 {
return nil, fmt.Errorf("Invalid numAttempts (expected: >=1, provided: %v)", numAttempts)
}
// 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.READ)
if err != nil {
return nil, errors.New("Device-specific registry key open failed: " + err.Error())
}
defer key.Close()
for {
// Read the NetCfgInstanceId value.
value, err := getRegStringValue(key, "NetCfgInstanceId")
if err != nil {
if errWin, ok := err.(syscall.Errno); ok && errWin == windows.ERROR_FILE_NOT_FOUND {
numAttempts--
if numAttempts > 0 {
// Wait and retry.
// TODO: Wait for a cancellable event instead.
time.Sleep(1000 * time.Millisecond)
continue
}
}
return nil, errors.New("RegQueryStringValue(\"NetCfgInstanceId\") failed: " + err.Error())
}
// Convert to windows.GUID.
ifid, err := guid.FromString(value)
if err != nil {
return nil, fmt.Errorf("NetCfgInstanceId registry value is not a GUID (expected: \"{...}\", provided: \"%v\")", value)
}
return ifid, err
}
}
//
// GetInterfaceName returns network interface name.
//