From ea59177f1c6ab9031d5d30771410c9514fa551d9 Mon Sep 17 00:00:00 2001 From: "Jason A. Donenfeld" Date: Thu, 7 Feb 2019 04:18:27 +0100 Subject: wintun: Introduce new package for obscuring Windows bits --- tun/tun_windows.go | 493 ++--------------------------------------------------- 1 file changed, 13 insertions(+), 480 deletions(-) (limited to 'tun/tun_windows.go') diff --git a/tun/tun_windows.go b/tun/tun_windows.go index d7cd762..6449974 100644 --- a/tun/tun_windows.go +++ b/tun/tun_windows.go @@ -5,20 +5,14 @@ package tun -//go:generate go run $GOROOT/src/syscall/mksyscall_windows.go -output ztun_windows.go tun_windows.go - import ( "errors" "fmt" "os" - "strings" - "syscall" - "time" "unsafe" - "git.zx2c4.com/wireguard-go/setupapi" + "git.zx2c4.com/wireguard-go/tun/wintun" "golang.org/x/sys/windows" - "golang.org/x/sys/windows/registry" ) const ( @@ -34,10 +28,6 @@ const ( TUN_SIGNAL_MAX = 2 ) -var deviceClassNetGUID = windows.GUID{0x4d36e972, 0xe325, 0x11ce, [8]byte{0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}} - -const TUN_HWID = "Wintun" - type tunPacket struct { size uint32 data [TUN_MAX_PACKET_SIZE]byte @@ -50,7 +40,7 @@ type tunRWQueue struct { } type nativeTun struct { - ifid *windows.GUID + wt *wintun.Wintun tunName string signalName *uint16 tunFile *os.File @@ -64,30 +54,28 @@ type nativeTun struct { func CreateTUN(ifname string) (TUNDevice, error) { // Does an interface with this name already exist? - ifid, err := getInterface(ifname, 0) - if ifid == nil || err != nil { + wt, err := wintun.GetInterface(ifname, 0) + if wt == nil || err != nil { // Interface does not exist or an error occured. Create one. - ifid, _, err = createInterface("WireGuard Tunnel Adapter", 0) + wt, _, err = wintun.CreateInterface("WireGuard Tunnel Adapter", 0) if err != nil { return nil, err } // Set interface name. (Ignore errors.) - setInterfaceName(ifid, ifname) + wt.SetInterfaceName(ifname) } - ifidStr := guidToString(ifid) - - signalNameUTF16, err := windows.UTF16PtrFromString(fmt.Sprintf("Global\\WINTUN_EVENT_%s", ifidStr)) + signalNameUTF16, err := windows.UTF16PtrFromString(wt.SignalEventName()) if err != nil { - deleteInterface(ifid, 0) + wt.DeleteInterface(0) return nil, err } // Create instance. tun := &nativeTun{ - ifid: ifid, - tunName: fmt.Sprintf("\\\\.\\Global\\WINTUN_DEVICE_%s", ifidStr), + wt: wt, + tunName: wt.DataFileName(), signalName: signalNameUTF16, events: make(chan TUNEvent, 10), errors: make(chan error, 1), @@ -96,7 +84,7 @@ func CreateTUN(ifname string) (TUNDevice, error) { // Create close event. tun.signals[TUN_SIGNAL_CLOSE], err = windows.CreateEvent(nil, 1 /*TRUE*/, 0 /*FALSE*/, nil) if err != nil { - deleteInterface(ifid, 0) + wt.DeleteInterface(0) return nil, err } @@ -160,7 +148,7 @@ func (tun *nativeTun) closeTUN() (err error) { } func (tun *nativeTun) Name() (string, error) { - return getInterfaceName(tun.ifid) + return tun.wt.GetInterfaceName() } func (tun *nativeTun) File() *os.File { @@ -184,7 +172,7 @@ func (tun *nativeTun) Close() error { close(tun.events) } - _, _, e = deleteInterface(tun.ifid, 0) + _, _, e = tun.wt.DeleteInterface(0) if err == nil { err = e } @@ -317,458 +305,3 @@ func (tun *nativeTun) Write(buff []byte, offset int) (int, error) { // Flush write buffer. return len(buff) - offset, tun.flush() } - -// -// getInterface finds interface ID 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 ID when the interface was found, or nil -// otherwise. -// -func getInterface(ifname string, hwndParent uintptr) (*windows.GUID, error) { - // Create a list of network devices. - devInfoList, err := setupapi.SetupDiGetClassDevsEx(&deviceClassNetGUID, "", hwndParent, setupapi.DIGCF_PRESENT, setupapi.DevInfo(0), "") - if err != nil { - return nil, err - } - defer devInfoList.Close() - - // Retrieve information associated with a device information set. - // TODO: Is this really necessary? - _, err = devInfoList.GetDeviceInfoListDetail() - if err != nil { - return nil, err - } - - // TODO: If we're certain we want case-insensitive name comparison, please document the rationale. - ifname = strings.ToLower(ifname) - - // Iterate. - for index := 0; ; index++ { - // Get the device from the list. - 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) - if err != nil { - // Something is wrong with this device. Skip it. - continue - } - - // Get interface name. - ifname2, err := getInterfaceName(ifid) - if err != nil { - // Something is wrong with this device. Skip it. - continue - } - - if ifname == strings.ToLower(ifname2) { - // Interface name found. - return ifid, nil - } - } - - 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) (*windows.GUID, bool, error) { - // Create an empty device info set for network adapter device class. - devInfoList, err := setupapi.SetupDiCreateDeviceInfoListEx(&deviceClassNetGUID, hwndParent, "") - if err != nil { - return nil, false, err - } - - // Get the device class name from GUID. - className, err := setupapi.SetupDiClassNameFromGuidEx(&deviceClassNetGUID, "") - if err != nil { - return nil, false, 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, 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, err - } - - // Set Plug&Play device hardware ID property. - hwid, err := syscall.UTF16FromString(TUN_HWID) - if err != nil { - return nil, false, err - } - err = devInfoList.SetDeviceRegistryProperty(deviceData, setupapi.SPDRP_HARDWAREID, setupapi.UTF16ToBuf(append(hwid, 0))) - if err != nil { - return nil, false, err - } - - // Search for the driver. - const driverType = setupapi.SPDIT_CLASSDRIVER - err = devInfoList.BuildDriverInfoList(deviceData, driverType) - if err != nil { - return nil, false, err - } - defer devInfoList.DestroyDriverInfoList(deviceData, driverType) - - driverDate := windows.Filetime{} - driverVersion := uint64(0) - 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 == 259 /*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(TUN_HWID) { - // 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 \"%v\" installed", TUN_HWID) - } - - // Call appropriate class installer. - err = devInfoList.CallClassInstaller(setupapi.DIF_REGISTERDEVICE, deviceData) - if err != nil { - return nil, false, err - } - - // Register device co-installers if any. - devInfoList.CallClassInstaller(setupapi.DIF_REGISTER_COINSTALLERS, deviceData) - - // Install interfaces if any. - devInfoList.CallClassInstaller(setupapi.DIF_INSTALLINTERFACES, deviceData) - - var ifid *windows.GUID - var rebootRequired bool - - // Install the device. - err = devInfoList.CallClassInstaller(setupapi.DIF_INSTALLDEVICE, deviceData) - if err == nil { - // Check if a system reboot is required. (Ignore errors) - if ret, _ := checkReboot(devInfoList, deviceData); ret { - rebootRequired = true - } - - // Get network interface ID from registry. Retry for max 30sec. - ifid, err = getInterfaceId(devInfoList, deviceData, 30) - } - - if err == nil { - return ifid, rebootRequired, nil - } - - // The interface failed to install, or the interface ID was unobtainable. Clean-up. - removeDeviceParams := setupapi.SP_REMOVEDEVICE_PARAMS{ - ClassInstallHeader: setupapi.SP_CLASSINSTALL_HEADER{ - InstallFunction: setupapi.DIF_REMOVE, - }, - Scope: setupapi.DI_REMOVEDEVICE_GLOBAL, - } - removeDeviceParams.ClassInstallHeader.Size = uint32(unsafe.Sizeof(removeDeviceParams.ClassInstallHeader)) - - // 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, false, 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 deleteInterface(ifid *windows.GUID, hwndParent uintptr) (bool, bool, error) { - // Create a list of network devices. - devInfoList, err := setupapi.SetupDiGetClassDevsEx(&deviceClassNetGUID, "", hwndParent, setupapi.DIGCF_PRESENT, setupapi.DevInfo(0), "") - if err != nil { - return false, false, err - } - defer devInfoList.Close() - - // Retrieve information associated with a device information set. - // TODO: Is this really necessary? - _, err = devInfoList.GetDeviceInfoListDetail() - if err != nil { - return false, false, err - } - - // Iterate. - for index := 0; ; index++ { - // Get the device from the list. - 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) - if err != nil { - // Something is wrong with this device. Skip it. - continue - } - - if ifid == ifid2 { - // Remove the device. - removeDeviceParams := setupapi.SP_REMOVEDEVICE_PARAMS{ - ClassInstallHeader: setupapi.SP_CLASSINSTALL_HEADER{ - InstallFunction: setupapi.DIF_REMOVE, - }, - Scope: setupapi.DI_REMOVEDEVICE_GLOBAL, - } - removeDeviceParams.ClassInstallHeader.Size = uint32(unsafe.Sizeof(removeDeviceParams.ClassInstallHeader)) - - // Set class installer parameters for DIF_REMOVE. - err = devInfoList.SetClassInstallParams(deviceData, &removeDeviceParams.ClassInstallHeader, uint32(unsafe.Sizeof(removeDeviceParams))) - if err != nil { - return false, false, err - } - - // Call appropriate class installer. - err = devInfoList.CallClassInstaller(setupapi.DIF_REMOVE, deviceData) - if err != nil { - return false, false, 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 -} - -/// -/// checkReboot checks device install parameters if a system reboot is required. -/// -func checkReboot(deviceInfoSet setupapi.DevInfo, deviceInfoData *setupapi.SP_DEVINFO_DATA) (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 -} - -// 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.SP_DEVINFO_DATA, 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\\ 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 { - // Query the NetCfgInstanceId value. Using get_reg_string() right on might clutter the output with error messages while the registry is still being populated. - _, _, err = key.GetValue("NetCfgInstanceId", nil) - 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("RegQueryValueEx(\"NetCfgInstanceId\") failed: " + err.Error()) - } - - // Read the NetCfgInstanceId value now. - value, err := getRegStringValue(key, "NetCfgInstanceId") - if err != nil { - return nil, errors.New("RegQueryStringValue(\"NetCfgInstanceId\") failed: " + err.Error()) - } - - // Convert to windows.GUID. - ifid, err := stringToGUID(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. -// -func getInterfaceName(ifid *windows.GUID) (string, error) { - // Open network interface registry key. - key, err := registry.OpenKey(registry.LOCAL_MACHINE, fmt.Sprintf("SYSTEM\\CurrentControlSet\\Control\\Network\\%v\\%v\\Connection", guidToString(&deviceClassNetGUID), guidToString(ifid)), registry.QUERY_VALUE) - if err != nil { - return "", errors.New("Network-specific registry key open failed: " + err.Error()) - } - defer key.Close() - - // Get the interface name. - return getRegStringValue(key, "Name") -} - -// -// setInterfaceName sets network interface name. -// -func setInterfaceName(ifid *windows.GUID, ifname string) error { - // Open network interface registry key. - key, err := registry.OpenKey(registry.LOCAL_MACHINE, fmt.Sprintf("SYSTEM\\CurrentControlSet\\Control\\Network\\%v\\%v\\Connection", guidToString(&deviceClassNetGUID), guidToString(ifid)), registry.SET_VALUE) - if err != nil { - return errors.New("Network-specific registry key open failed: " + err.Error()) - } - defer key.Close() - - // Set the interface name. - return key.SetStringValue("Name", ifname) -} - -//sys clsidFromString(lpsz *uint16, pclsid *windows.GUID) (hr int32) = ole32.CLSIDFromString - -// -// stringToGUID parses "{XXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX}" string to GUID. -// -func stringToGUID(str string) (*windows.GUID, error) { - strUTF16, err := syscall.UTF16PtrFromString(str) - if err != nil { - return nil, err - } - - guid := &windows.GUID{} - - hr := clsidFromString(strUTF16, guid) - if hr < 0 { - return nil, syscall.Errno(hr) - } - - return guid, nil -} - -// -// guidToString function converts GUID to string -// "{XXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX}". -// -// The resulting string is uppercase. -// -func guidToString(guid *windows.GUID) string { - return fmt.Sprintf("{%06X-%04X-%04X-%04X-%012X}", guid.Data1, guid.Data2, guid.Data3, guid.Data4[:2], guid.Data4[2:]) -} - -// -// getRegStringValue function reads a string value from registry. -// -// If the value type is REG_EXPAND_SZ the environment variables are expanded. -// Should expanding fail, original string value and nil error are returned. -// -func getRegStringValue(key registry.Key, name string) (string, error) { - // Read string value. - value, valueType, err := key.GetStringValue(name) - if err != nil { - return "", err - } - - if valueType != registry.EXPAND_SZ { - // Value does not require expansion. - return value, nil - } - - valueExp, err := registry.ExpandString(value) - if err != nil { - // Expanding failed: return original sting value. - return value, nil - } - - // Return expanded value. - return valueExp, nil -} -- cgit v1.2.3